当前期刊: "其他"类期刊
显示样式:        排序: 导出
我的关注
我的收藏
您暂时未登录!
登录
  • Bubble-in-drop microextraction of carbamate pesticides followed by gas chromatography-mass spectrometric analysis
    Microchem. J. (IF 3.206) Pub Date : 2020-01-21
    Kochaporn Chullasat; Zhenzhen Huang; Opas Bunkoed; Proespichaya Kanatharana; Hian Kee Lee

    Bubble-in-drop microextraction (BID) is a variation of single-drop microextraction in which an air bubble is deliberately introduced to the solvent to enhance extraction efficiency. Here, BID coupled with GC-MS was developed for the extraction, enrichment and determination of carbamate pesticides in environmental water samples. Conditions affecting BID performance including the type of extraction solvent and its volume, volume of air bubble, extraction time, stirring rate, salt concentration and sample pH were evaluated. Under the most favorable BID conditions, the method provided good linearities from 0.05 to 20.0 μg L−1 with the coefficients of determination higher than 0.99. Enrichment factors were determined to be between 536 and 1097. The limits of detection and limits of quantification were in the ranges of 0.02 to 0.04 μg L−1, and 0.05 to 0.13 μg L−1, respectively. BID-GC-MS was successfully applied to the determination of carbamate pesticides in water samples with satisfactory recoveries from 81.7% to 99.0%, and intra-day and inter-day precision (relative standard deviations of <7% and <8%, respectively).

    更新日期:2020-01-21
  • Application of statistical analyses for Lapis Lazuli stone provenance determination by XRL and XRF
    Microchem. J. (IF 3.206) Pub Date : 2020-01-18
    Miriam Saleh; Letizia Bonizzoni; Jacopo Orsilli; Sabrina Samela; Marco Gargano; Salvatore Gallo; Anna Galli

    Lapis Lazuli use stretches back more than 6,500 years; ancient civilizations of Mesopotamia, Egypt, China, Greece, and Rome treasured and prized it. Afghanistan has been the oldest source for this stone, while Chile, Canada, Russia and a few other countries have been reported as sources for raw material in more recent times; the rarity of historical mines surely represents a positive aspect for the provenance clue of artefacts. Lapis lazuli is a rock consisting mainly of lazurite, to which it owes the blue colour, calcite and pyrite. Other constituents may be present, related to the different mines. In the present work, we apply the principles of Radio-luminescence (RL) exploiting as radiation source the X-ray tube of a portable commercial X-Ray Fluorescence spectrometer; in this way, X-Ray Fluorescence spectra (XRF) can be simultaneously acquired to have a larger set of data. To highlight the instrumental experimental differences, we refer to the portable set up as X-Ray Luminescence (XRL), as suggested by recent literature. We thus looked for the possibility of applying a wieldy, low cost and non-destructive method that could fit also to precious objects, based on the join use of XRF and XRL. We performed analyses on raw Lapis Lazuli stones from five different provenances, both historical and modern, and on four sets of unknown origin carved polished stones, to test our methods on real artefacts. We focalised on a limited number of samples to concentrate on the statistical treatment of spectra obtained, so to get a synergic response of the two applied techniques. We were able to obtain a clear distinction for the different classified provenances and could speculate those of unknown samples.

    更新日期:2020-01-21
  • Evaluation of antibiotic resistance and prevalence of common Salmonella enterica serovars isolated from foodborne outbreaks
    Microchem. J. (IF 3.206) Pub Date : 2020-01-17
    Zahra Rahimi Nadi; Taghi Zahraei Salehi; Iradj Ashrafi Tamai; Abbas Rahimi foroushani; Mika Sillanpaa; Mohammad Mehdi Soltan Dallal

    Salmonella is one of the major causes of foodborne outbreaks and numerous studies have reported the presence of its serovars in foodborne outbreaks. Identification of the most prevalent serovars, common polluted food types and attention to the antibiotic resistance of its serovars, are therefore key factors in the prevention and control of salmonellosis. The aim of this study is thus isolation of the common Salmonella serovars, identification of corresponding food categories and determination of their antibiotic resistance status in the stool samples of people poisoned in foodborne outbreaks in Iran during the period 2013 to 2019. Salmonella strain was isolated with serotyping and antibiogram test on 1,425 collected stools. Among them, 83 samples (5.8%) contain salmonella strain .The most frequent serovars were S. enteritidis and S. senftenberg, respectively (26.3%, 21.3%). The highest salmonellosis incidence rates were observed in the consumption of cooked meat (64.2%) then fruits and vegetables (21.4%). According to our findings, an increase in the prevalence of Salmonella senftenberg in foodborne outbreaks with 5.3% resistance to extended spectrum cephalosporins such as ceftazidime and cefotaxime, and a decrease in cefepime sensitivity and nalidixic acid resistance could be warnings of the emergence of this serovar with increasing antibiotic resistance.

    更新日期:2020-01-21
  • Simultaneous detection of ammonia and nitrate using a modified electrode with two regions
    Microchem. J. (IF 3.206) Pub Date : 2020-01-17
    Jingyi Wang; Peng Diao

    Simultaneous detection of ammonia and nitrate has significance in the application areas of environment and industry. Conventional methods include additional steps to separate ammonia and nitrate before detection. A more convenient method is required to detect ammonia and nitrate directly in their mixture. In this work, a modified electrode with electrodeposited Pt region and Ag region was prepared to simultaneously detect ammonia and nitrate for the first time. The Pt region and Ag region were designed to selectively determine ammonia and nitrate, respectively, free of interference with each other. A nonlinear correlation between ammonia oxidation current and ammonia bulk concentration and a linear correlation between nitrate reduction current and nitrate bulk concentration were found. The simultaneous detection limits of ammonia and nitrate were 3.946 μM and 0.134 mM, respectively. The modified electrode showed good long-term stability for the simultaneous detection of ammonia and nitrate with relative standard deviations of 7.10% and 3.93%, respectively. The modified electrode exhibited good anti-interference ability toward Na+, K+, Cl− and SO42−. This work demonstrated a simple and fast approach for detecting two components in solution.

    更新日期:2020-01-21
  • Experimental and numerical investigations of similarity for dam-break flows on wet bed
    J. Hydrol. (IF 4.405) Pub Date : 2020-01-21
    Bo Wang; Wenjun Liu; Wei Wang; Jianmin Zhang; Yunliang Chen; Yong Peng; Xin Liu; Sha Yang

    The similarity brings great convenience to the description of the dam-break flows. The previous works mainly focus on the similarity of dam-break flows under the condition of dry bed downstream. In view of the fact that there is often a certain tail water depth in a river, this paper deals with both the gravity similarity and self-similarity of dam-break flows in a horizontal and smooth channel with a wet-bed downstream condition by using both physical and numerical models. In the laboratory tests, the digital image processing technique is adopted for flow measurement, providing water surface profiles, stage hydrographs and cross-sectional mean velocity. Three different upstream depths and ten water depth ratios α (i.e., the ratio of initial downstream water depth against the upstream water depth, ranging from 0.05 to 0.9) are considered. The numerical simulations on the vertical two-dimensional experiments are carried out using a computational fluid dynamics solver, providing velocity profiles in addition to the hydraulic parameters obtained in experiments. The following observations are made: (1) the water surface profiles, stage hydrographs, mean velocity distribution and horizontal velocity profiles are shown to satisfy the gravity similarity well; (2) the gravity similarity characteristic of the vertical velocity profiles in the reservoir performs better than that in the flooded area; (3) the water surface profiles, mean velocity distribution and horizontal velocity profiles approximately satisfy the self-similarity after a period of time for α < 0.3; (4) the undulations both in the rarefaction wave and the shock front destroy the self-similarity of dam-break flow for α ≥ 0.3, except that the self-similarity is valid in two non-undulation areas (located upstream the extra negative wave and in the neighborhood of dam site) after a period of time; (5) the gravity similarity could be applied in the small-scaled physical model of dam-break flow and the water depth ratio must be considered when applying the self-similarity; (6) the measurements and numerical simulations with the large eddy simulation (LES) model show satisfactory agreement, implying that the LES modeling is a viable approach for accurately predicting the dam-break flows with a wet bed downstream condition.

    更新日期:2020-01-21
  • Spatial-temporal rain field generation for the Guangdong-Hong Kong-Macau Greater Bay Area considering climate change
    J. Hydrol. (IF 4.405) Pub Date : 2020-01-20
    Yejia Qiang; Limin Zhang; Te Xiao

    A stochastic rainfall generator is required to provide rainfall inputs for the analysis and mitigation of such hydrological or geologic hazards as floods and rain-induced landslides. This paper presents a new spatial-temporal rainstorm generator for generating simultaneous rainfall processes at numerous locations considering the spatial correlation among these locations and interpolating the point processes into an areal rain field. The generator is able to include the effect of climate change by adjusting the parameters of the marginal distributions of variables constituting rain events. A case study on the Guangdong-Hong Kong-Macau Greater Bay Area (GBA), one of the regions that are most prone to storm-related disasters in the world, is presented. The performance of the proposed generator is excellent in reproducing the historical statistical characteristics of regional rainfall. The model is adapted to climate change through extrapolation of the variation trend of the model parameters in the observation period to explore possible future scenarios of regional rainfall in GBA. The simulation results indicate a significant increase in rainfall extremes, especially for short-duration rainfall, at the end of 21st century in GBA.

    更新日期:2020-01-21
  • Hydrologic response in the karstic and basaltic hydro-geological units of Lake Kinneret Watershed
    J. Hydrol. (IF 4.405) Pub Date : 2020-01-20
    Matan Ben Yona; Alon Rimmer; Eylon Shamir; Iggy Litaor

    The hydrologic responses of two similar in size watersheds in the Lake Kinneret basin are examined: Karstic Hermon watershed and basaltic Meshushim watershed. The streamflow properties at these watersheds are different in their surface flow to baseflow ratio, runoff coefficients and response to extreme rainfall events. The HYdrological Model for Karst Environment (HYMKE) model, developed to simulate daily flow in karst formation, was modified to address the basaltic formation at the Meshushim watershed. Water fluxes simulations were used to compare the hydrologic processes between the watersheds. The twice-higher annual precipitation in the Hermon watershed, generates annual streamflow that is five times more than in the Meshushim. This amplification of the rainfall-streamflow ratio between the watersheds is because larger fraction of the rainfall is lost to evapotranspiration at the basaltic Meshushim watershed and larger portion of the rainfall percolates to the karstic aquifer through preferential flow and appear as baseflow at the Hermon watershed. During large rainfall events when soil water content is near saturation, lower rainfall amount over the Meshushim watershed generates larger peak flow than the Hermon watershed. In both watersheds, surface flow was generated only when the soil water content is at or near saturation conditions. The streamflow dependency on soil water content, suggests high sensitivity of streamflow generation to the intra-annual variability of precipitation. Understanding the hydrologic response of the different sources of Lake Kinneret improves the ability to forecast its inflow.

    更新日期:2020-01-21
  • Interbasin Groundwater Flow: Characterization, Role of karst areas, Impact on annual water balance and flood processes
    J. Hydrol. (IF 4.405) Pub Date : 2020-01-20
    Martin Le Mesnil; Jean-Baptiste Charlier; Roger Moussa; Yvan Caballero; Nathalie Dörfliger
    更新日期:2020-01-21
  • Using Cluster Analysis for Understanding Spatial and Temporal Patterns and Controlling Factors of Groundwater Geochemistry in a Regional Aquifer
    J. Hydrol. (IF 4.405) Pub Date : 2020-01-20
    Jing Yang; Ming Ye; Zhonghua Tang; Tian Jiao; Xiaoyu Song; Yongzhen Pei; Honghua Liu
    更新日期:2020-01-21
  • Temperature Dependence of Extreme Precipitation over Mainland China
    J. Hydrol. (IF 4.405) Pub Date : 2020-01-20
    Xichao Gao; Ming Guo; Zhiyong Yang; Qian Zhu; Zhi Xu; Kai Gao

    The relationship between extreme precipitation and the corresponding temperature is of great importance for predicting precipitation extremes in the future, given the rapid increase of global warming. This study investigates the relationship between extreme precipitation and the corresponding daily mean temperature over mainland China based on the China Meteorological Assimilation Driving Datasets for the Soil and Water Assessment Tool (CMADS). The relationship between extreme precipitation and daily maximum temperature before rainfall as well as that between relative humidity and daily mean temperature is investigated. The results show that (1) Among the patterns of the relationship between extreme precipitation and corresponding daily mean temperature, the peak pattern is dominant over mainland China, accounting for 95.80% of all the patterns; (2) a scaling of extreme precipitation with daily mean temperature greater than that represented by the C–C scaling is observed in most parts of China; (3) the peak-point extreme precipitation decreases from the southeast to the northwest of China, whereas the peak-point temperature ranges from 15 ℃ to 25 ℃; (4) for most regions of China, the decreases in the relative humidity and the cooling effect of heavy extreme precipitation and its synoptic system contribute to the peak or negative pattern of the relationship between extreme precipitation and the corresponding daily mean temperature; and (5) compared with the cooling effect, the decrease of relative humidity is the first-order reason for the peak or negative pattern of the relationship between extreme precipitation and the corresponding daily mean temperature.

    更新日期:2020-01-21
  • Development of a partial copula-based algorithm for disclosing variability of dependence structures between hydro-meteorological factors under consideration of covariate-effect
    J. Hydrol. (IF 4.405) Pub Date : 2020-01-20
    Aijun Guo; Jianxia Chang; Yimin Wang; Qiang Huang; Zhihui Guo; Yunyun Li

    Investigating variability of dependence structures between hydro-meteorological factors (DSHF) is of critical importance for throwing light on mechanisms of hydrological cycle under changing environment. Previous studies mostly focused on examining variability of single hydro-meteorological variable in forms of change point while neglecting complicated interactions among hydro-meteorological variables and thus failing to fully reveal variability of hydrological cycle. In this study, a partial copula-based likelihood-ratio (PaCoLR) test algorithm is developed for disclosing change point of DSHF whilst controlling for the effect of covariate. Eight major catchments across the Loess Plateau (LP), China, are selected as study regions. Results indicate that change points of dependence structures between streamflow and precipitation / potential evapotranspiration varies across the LP due to the spatial heterogeneity of climate and anthropogenic activities. Moreover, change points of dependence structure between precipitation and potential evapotranspiration on the LP match well with the time of global warming hypothesis, i.e. the early 1980s. Additionally, we find that controlling for the effect of precipitation is extremely essential when examining change point of dependence structure between streamflow and potential evapotranspiration on rain-dominated region, such as the LP. Further, the proposed PaCoLR algorithm is also applicable for detecting change points of DSHF in transient snow and snowmelt dominant regions.

    更新日期:2020-01-21
  • River discharge estimation from radar altimetry: assessment of satellite performance, river scales and methods
    J. Hydrol. (IF 4.405) Pub Date : 2020-01-20
    E. Zakharova; K. Nielsen; G. Kamenev; A. Kouraev

    The ENVISAT, Jason -2 and -3, Sentinel-3A, CryoSat-2, and AltiKa satellite altimeters were used to estimate the discharge of two Arctic rivers: the Ob and Pur in western Siberia. The accuracy of the water height estimates from ENVISAT varied with river size from 0.63 m for the Ob (∼2 km in width) to 1.1 m for the Pur (∼0.5 km in width). A new method for water level estimation combining the CryoSat-2, AltiKa, and Sentinel-3A altimeters provided better height accuracy (0.49 m for the Ob). The rating curve method of discharge estimation outperforms the Manning formulation, on the Ob, with a root mean square error (RMSE) of 13% vs 20% for daily discharge and 1% vs 5% for annual discharge. Sensitivity analysis performed on the Manning formulation showed high sensitivity to the river depth parameterisation. A functional relationship was identified between the depth of rivers, in the north of western Siberia, and their widths and deposits types. The combination, for the Ob, of the rating curve method with the multi-satellite water level retrieval algorithm provided higher discharge accuracy than previous studies relying on satellite measurements, on numerical modelling or on their combination. A synthesis of worldwide river altimetry studies supported our finding that the accuracy of altimetric discharge estimations decreases for narrower rivers. The rating curve method applied to Jason 2/3 height measurements allows estimation of daily discharges with RMSE of 18% for the wide Ob River but 38% for the narrow Pur River.

    更新日期:2020-01-21
  • Analyses of leakage effect of waterproof curtain during excavation dewatering
    J. Hydrol. (IF 4.405) Pub Date : 2020-01-18
    Yong-Xia Wu; Shui-Long Shen; Hai-Min Lyu; Annan Zhou

    The waterproof curtain that is used to block groundwater, leaks occasionally during deep excavation and can have a harmful impact on the surroundings. This study adopts a three-dimensional (3D) fluid-solid coupled finite element model (FEM) to analyze the impact due to a leakage in the waterproof curtain during excavation dewatering. In the model, both a user-defined one-dimensional leakage element and a solid leakage element are incorporated to simulate the leakage. The leakage of the curtain in the soil is analysed by monitoring the variation in hydraulic conductivity. The simulated results demonstrate that the leaking rate, leaking volume, groundwater drawdown, and ground settlement are closely related to the hydraulic conductivity of the leakage point. The results also show that the groundwater head outside the pit declines quickly when the leakage occurs, but soil consolidation proceeds slowly. In addition, the characteristics of the soil that is adjacent to the leakage point also have a tangible effect on the groundwater head and ground settlement. The hydraulic conductivity and deformation modulus of the soil has a significant effect on the ground settlement, while the influence of the anisotropy of the soil is relatively low.

    更新日期:2020-01-21
  • The probability of breaching water quality standards – a probabilistic model of river water nitrate concentrations
    J. Hydrol. (IF 4.405) Pub Date : 2020-01-18
    Fred Worrall; Brandon Kerns; Nicholas J.K. Howden; Tim P. Burt; Helen P. Jarvie

    In this study we propose an approach to predicting the probability that river waters will exceed a water quality standard. The study used a two-part generalised linear modelling approach within a Bayesian framework. Binomial regression was used to model the probability that a water quality standard would be exceeded and included two factors - the difference between sampling sites and difference between years of sampling. Using a Bayesian approach meant that information could be drawn from all observations from all sites, across all years, and that all results would come with a measure of uncertainty. Furthermore, although some known factors could not be included in the binomial regression, they could be included using Bayes’ rule to enhance and inform the results. This approach was applied to assessing the probability of nitrate concentrations in English river waters exceeding the current nitrate water quality standard of 11.3 mg N /l. The study showed that the Bayesian approach decreased the measures of uncertainty in the predicted outcomes was reduced by an average of 60% and increased the effective sample size by 64%.The best-fit model had a root mean square error (RMSE) of 7.9% which equated to an error of ± 1 sample above the water quality standard for the median site. When interaction of factors could be included, then RMSE decreased to 3.8%. It was not possible to include a diurnal cycle, owing to a paucity of sub-daily sampling, but there was a significant seasonal cycle and so outputs could be adjusted by means of Bayes’ rule to predict water quality standard exceedance each month. Comparison with the current method of classification shows no significant difference between five out of the six lowest classifications with only the highest classification being correlated with the estimated exceedence rate. With respect to nitrate in English river waters, the average exceedance rate was 8.3% but was declining at a statistically-significant rate of 0.09 %/yr2.

    更新日期:2020-01-21
  • Soil Hydraulic Parameters Estimation using Ground Penetrating Radar Data via Ensemble Smoother with Multiple Data Assimilation
    J. Hydrol. (IF 4.405) Pub Date : 2020-01-17
    Fan Cui; Jichao Bao; Zhendan Cao; Liangping Li; Qiang Zheng

    Ground Penetrating Radar (GPR) has been widely used for shallow subsurface exploration in recent decades. The Ensemble Smoother with Multiple Data Assimilation (ES-MDA) was proposed and has been proved as one of the most efficient algorithms for data assimilation in variational fields. In this paper, ES-MDA is first applied as the assimilation scheme to inversely model the soil hydraulic parameters by using GPR data as the observation. In a synthetic example presented, Hydrus-1D is applied to generate the water content data and later converted into GPR data as observations based on the petrophysical relationship. Several synthetic experiments are performed to evaluate the related factors and test the performance of GPR data assimilation via ES-MDA. The results show that the novel approach can accurately estimate soil hydraulic parameters and effectively characterize the water content distribution.

    更新日期:2020-01-21
  • Immunological axis of berberine in managing inflammation underlying chronic respiratory inflammatory diseases
    Chem. Biol. Interact. (IF 3.407) Pub Date : 2020-01-20
    Xin Nee Tew; Natalie Jia Xin Lau; Dinesh Kumar Chellappan; Thiagarajan Madheswaran; Farrukh Zeeshan; Murtaza M. Tambuwala; Alaa AA. Aljabali; Sri Renukadevi Balusamy; Haribalan Perumalsamy; Gaurav Gupta; Brian G. Oliver; Alan Hsu; Peter Wark; Karosham Reddy; Ridhima Wadhwa; Philip Michael Hansbro; Kamal Dua

    Inflammatory responses play a remarkable role in the mechanisms of acute and chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD), asthma, pulmonary fibrosis and lung cancer. Currently, there is a resurgence in the use of drugs from natural sources for various ailments as potent therapeutics. Berberine, an alkaloid prominent in the Chinese traditional system of medicine has been reported to exert therapeutic properties in various diseases. Nevertheless, the number of studies focusing on the curative potential of berberine in inflammatory diseases involving the respiratory system is limited. In this review, we have attempted to discuss the reported anti-inflammatory properties of berberine that function through several pathways such as, the NF-κB, ERK1/2 and p38 MAPK pathways which affect several pro-inflammatory cytokines in the pathophysiological processes involved in chronic respiratory diseases. This review would serve to provide valuable information to researchers who work in this field and a new direction in the field of drug discovery with respect to respiratory diseases.

    更新日期:2020-01-21
  • Understanding the Psychological Distress of Food Insecurity: A Qualitative Study of Children’s Experiences and Related Coping Strategies
    J. Acad. Nutr. Diet. (IF 4.141) Pub Date : 2020-01-17
    Cindy W. Leung; Anita L. Stewart; Eduardo T. Portela-Parra; Nancy E. Adler; Barbara A. Laraia; Elissa S. Epel

    Background Food insecurity, a condition of inadequate household food availability, affects 15.7% of US households with children. Food insecurity is generally believed to affect the quantity and quality of food consumed. However, an understudied but important aspect of the experience of food insecurity is psychological distress. Objective To critically explore the psychological distress associated with children’s food insecurity using children’s own reports of their experiences. Design In-depth qualitative interviews conducted with children to better understand the psychological distress associated with food insecurity. Participants/setting Sixty children (aged 7 to 14 years) were recruited from the San Francisco Bay Area. Children were eligible in the case that they spoke English fluently and their parent reported any experience of household food insecurity during the past year. Results Children discussed six themes related to the psychological distress associated with food insecurity: worrying about not having enough food, worrying about their parents’ well-being, anger and frustration about not having enough food, embarrassment about their family’s food situation, strain on the family’s dynamics due to food insecurity, and sadness over not having enough food. After describing their experiences, children described strategies they employed to tolerate or cope with food insecurity, including distracting from or using their imagination to cope with food insecurity, increasing tolerance of their family’s food situation, and appreciating their parents for providing food and resources. Conclusions Food insecurity contributes to children’s psychological distress. Given the known effects of chronic stress in childhood, the psychological distress of food insecurity may represent an important mechanism by which food insecurity adversely influences children’s growth and development and deserves investigation in future studies.

    更新日期:2020-01-21
  • The effects of manganese overexposure on brain health
    Neurochem. Int. (IF 3.994) Pub Date : 2020-01-20
    Mahfuzur R. Miah; Omamuyovwi M. Ijomone; Comfort O.A. Okoh; Olayemi K. Ijomone; Grace T. Akingbade; Tao Ke; Bárbara Krum; Airton da Cunha Martins; Ayodele Akinyemi; Nicole Aranoff; Felix Alexandre Antunes Soares; Aaron B. Bowman; Michael Aschner

    Manganese (Mn) is the twelfth most abundant element on the earth and an essential metal to human health. Mn is present at low concentrations in a variety of dietary sources, which provides adequate Mn content to sustain support various physiological processes in the human body. However, with the rise of Mn utility in a variety of industries, there is an increased risk of overexposure to this transition metal, which can have neurotoxic consequences. This risk includes occupational exposure of Mn to workers as well as overall increased Mn pollution affecting the general public. Here, we review exposure due to air pollution and inhalation in industrial settings; we also delve into the toxic effects of manganese on the brain such as oxidative stress, inflammatory response and transporter dysregulation. Additionally, we summarize current understandings underlying the mechanisms of Mn toxicity.

    更新日期:2020-01-21
  • Fluoxetine improves behavioural deficits induced by chronic alcohol treatment by alleviating RNA editing of 5-HT2C receptors
    Neurochem. Int. (IF 3.994) Pub Date : 2020-01-20
    Zexiong Li; Yan Lu; Shanshan Liang; Shuai Li; Beina Chen; Manman Zhang; Maosheng Xia; Dawei Guan; Alexei Verkhratsky; Baoman Li
    更新日期:2020-01-21
  • Fullerene derivatives with amino acids, peptides and proteins: from synthesis to biomedical application
    Prog. Solid State Chem. (IF 6.077) Pub Date : 2020-01-20
    Evgeniia I. Pochkaeva; Nikita E. Podolskiy; Dmitry N. Zakusilo; Andrey V. Petrov; Nikolay A. Charykov; Timur D. Vlasov; Anastasia V. Penkova; Lubov V. Vasina; Igor V. Murin; Vladimir V. Sharoyko; Konstantin N. Semenov

    Fullerene derivatives with amino acids, peptides and proteins have wide perspectives in biomedical applications. Thus, development and up-scaling of synthesis procedures, as well as investigation of the physico-chemical and biological properties of these derivatives, are extremely important. The present paper systematizes the current literature data on synthesis, physico-chemical properties and application of fullerene derivatives with amino acids, peptides and proteins in biomedicine. Experimental and theoretical data presented in the review give a comprehensive overview of these substances and can be valuable for specialists in the fields of nanotechnology, nanomaterials and bionanomedicine.

    更新日期:2020-01-21
  • 更新日期:2020-01-21
  • 更新日期:2020-01-21
  • 更新日期:2020-01-21
  • Synthesis, structure, and properties of complexes based on 3, 5-di-(Triazole-1-yl)-Benzoic acid ligands
    J. Solid State Chem. (IF 2.291) Pub Date : 2020-01-18
    Yang Yunxia; Xia Shiying; Zhang Haixia; Niu Huihui; Dong Wenjing; Wu Xiangxiang
    更新日期:2020-01-21
  • 更新日期:2020-01-21
  • Biological nutrient removal and recovery from solid and liquid livestock manure: Recent advance and perspective
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-21
    Muhammad Zubair; Siqi Wang; Panyue Zhang; Junpei Ye; Jinsong Liang; Mohammad Nabi; Zeyan Zhou; Xue Tao; Na Chen; Kai Sun; Junhong Xiao; Yajing Cai
    更新日期:2020-01-21
  • Biorefinery of spent coffee grounds waste: Viable pathway towards circular bioeconomy
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-21
    J. Rajesh banu; S. Kavitha; R. Yukesh Kannah; M. Dinesh Kumar; J. Preethi; A.E. Atabani; Gopalakrishnan kumar

    The circular bioeconomy plan is an innovative research based scheme intended for augmenting the complete utilization and management of bio-based resources in a sustainable biorefinery route. Spent coffee grounds based biorefinery is the emerging aspect promoting circular bioeconomy. The sustainable circular bioeconomy by utilizing SCG is achieved by cascade approaches and the inclusion of many biorefinery approaches to obtain many bio-products. The maximum energy recovery can be obtained by process integration. The economic analysis of the biofuel production from SCG is dependent on the cost of raw material, transportation, the need of labor and energy, oil extraction operations and biofuel production. The inclusion of new products from already established product can minimize the investment cost when related to the production cost. A positive net present value can be achieved via SCG biorefinery which indicates the profitability of the process.

    更新日期:2020-01-21
  • 更新日期:2020-01-21
  • 更新日期:2020-01-21
  • Enhancement of dark fermentative H2 production by gas separation membranes: A review
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-21
    Nándor Nemestóthy; Katalin Bélafi-Bakó; Péter Bakonyi

    Biohydrogen production via dark fermentation is currently the most developed method considering its practical readiness for scale-up. However, technological issues to be resolved are still identifiable and should be of concern, particularly in terms of internal mass transfer. If sufficient liquid-to-gas H2 mass transfer rates are not ensured, serious problems associated with the recovery of biohydrogen and consequent inhibition of the process can occur. Therefore, the continuous and effective removal of H2 gas is required, which can be performed using gas separation membranes. In this review, we aim to analyze the literature experiences and knowledge regarding mass transfer enhancement approaches and show how membranes may contribute to this task by simultaneously processing the internal (headspace) gas, consisting mainly of H2 and CO2. Promising strategies related to biogas recirculation and integrated schemes using membranes will be presented and discussed to detect potential future research directions for improving biohydrogen technology.

    更新日期:2020-01-21
  • Microalgae based biorefinery promoting circular bioeconomy- Techno economic and life-cycle analysis
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-21
    J. Rajesh banu; Preethi Writing original draft; S. Kavitha; M. Gunasekaran; Gopalakrishnan kumar
    更新日期:2020-01-21
  • Biodegradation of Congo red dye in a moving bed biofilm reactor: Performance evaluation and kinetic modeling
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-21
    Ravi Kumar Sonwani; Ganesh Swain; Balendu Shekhar Giri; Ram Sharan Singh; Birendra Nath Rai
    更新日期:2020-01-21
  • Minimizing membrane bioreactor environmental footprint by multiple objective optimization
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-20
    Giorgio Mannina; Bing-Jie Ni; Taise Ferreira Rebouças; Alida Cosenza; Gustaf Olsson
    更新日期:2020-01-21
  • Anthraquinone-2,6-disulfonate enhanced biodegradation of dibutyl phthalate: reducing membrane damage and oxidative stress in bacterial degradation
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-20
    Ying Zhang; Hongtao Shi; Jidong Gu; Yaqi Jiao; Siyue Han; Modupe Sarah Akindolie; Yifan Wang; Lin Zhang; Yue Tao
    更新日期:2020-01-21
  • Effects of exposure to polyether sulfone microplastic on the nitrifying process and microbial community structure in aerobic granular sludge
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-20
    Ronghua Qin; Chengyuan Su; Weihong Liu; Linqin Tang; Xinjuan Li; Xue Deng; Anliu Wang; Zhengpeng Chen
    更新日期:2020-01-21
  • Increasing the methane production rate of hydrogenotrophic methanogens using biochar as a biocarrier
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-20
    Hao-Jie Yang; Zhi-Man Yang; Xiao-Hui Xu; Rong-Bo Guo
    更新日期:2020-01-21
  • Resource recovery from wastewaters using microalgae-based approaches: A circular bioeconomy perspective
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-20
    Dillirani Nagarajan; Duu-Jong Lee; Chun-Yen Chen; Jo-Shu Chang
    更新日期:2020-01-21
  • Fate of antibiotics, antibiotic-resistant bacteria, and cell-free antibiotic-resistant genes in full-scale membrane bioreactor wastewater treatment plants
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-20
    Shuo Wang; Xinxin Ma; Yalan Liu; Xuesong Yi; Guocheng Du; Ji Li

    The removal of antibiotics, antibiotic-resistant bacteria (ARB), and cell-free antibiotic-resistant genes (ARGs) and the microbial community of ARB were investigated in detail to understand their fate and provide valuable information on the feasibility of full-scale membrane bioreactor (MBR). The potential risks of cell-free ARGs to the receiving environment were discovered. High influent antibiotic concentration could inhibit the microbial activity of MBR sludge, whereas good antibiotic removal could be maintained because of relatively long solid retention time and high biomass retention. Approximately 61.8%–77.5% of the total antibiotics were degraded, and 22.5%–38.2% of the total antibiotics were adsorbed by MBR sludge on average. The individual antibiotic removal presented intense discrepancy because of the chemical construction and distribution coefficient of antibiotics. Aeromonas exhibited specific antibiotic resistance to ampicillin and erythromycin, Escherichia became the predominant genera in kanamycin-ARB and tetracycline-ARB, and Klebsiella and Bacteroides were the particular genera that exhibited distinct antibiotic resistance to ciprofloxacin. A significant correlation was found between cell-free ARG abundance and ARB content, and relatively high effluent cell-free ARG abundance facilitated the proliferation and transmission of ARB. The impacts of the receiving environment to eliminate the ecological risks and severe threats to human health should be investigated because of the low decay ratio and long-term persistence of cell-free ARGs.

    更新日期:2020-01-21
  • Cultivating Chlorella sorokiniana AK-1 with swine wastewater for simultaneous wastewater treatment and algal biomass production
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-20
    Chun-Yen Chen; En-Wei Kuo; Dillirani Nagarajan; Shih-Hsin Ho; Cheng-Di Dong; Duu-Jong Lee; Jo-Shu Chang
    更新日期:2020-01-21
  • Integrating bran starch hydrolysates with alkaline pretreated soft wheat bran to boost sugar concentration
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-20
    Jikai Zhao; Youjie Xu; Meng Zhang; Donghai Wang

    Soft wheat bran (SWB), one of the most abundant byproducts from the wheat milling industry, is a potential candidate for biofuel production. In this study, bran starch hydrolysates were separately integrated with dilute acid pretreated SWB and alkaline pretreated SWB to boost fermentable sugar concentration. Alkaline pretreatment showed higher sugar recoveries than acid pretreatment. Significant sugar degradation for acid pretreatment was observed when pretreatment temperature higher than 170 ℃. The optimal pretreatment condition was 15% solid loading with 0.08 mol/L NaOH at 150 ℃ for 20 min. The neutralization reaction between dilute alkaline and released acids reduced sugar decomposition and inhibitors formation. Integrating bran starch hydrolysates with alkaline pretreated SWB yielded the highest glucose concentration of 50.91 g/L and a total sugar concentration of 101.29 g/L.

    更新日期:2020-01-21
  • Effect of excess activated sludge on vermicomposting of fruit and vegetable waste by using novel vermireactor
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-18
    Wenjiao Li; Sartaj Ahmad Bhat; Jiefeng Li; Guangyu Cui; Yongfen Wei; Toshiro Yamada; Fusheng Li
    更新日期:2020-01-21
  • DNA-based stable isotope probing identifies triclosan degraders in nitrification systems under different surfactants
    Bioresource Technol. (IF 6.669) Pub Date : 2020-01-17
    Jing-Xin Jia; Jing-Feng Gao; Hui-Hui Dai; Wen-Zhi Zhang; Da Zhang; Zhi-Qi Wang
    更新日期:2020-01-21
  • Facile Synthesis of CoS2 Nanoparticles/Nitrogen‐Doped Graphitic Carbon /Carbon Nanotubes Composites as Advanced Anode for Sodium‐ion Batteries
    ChemElectroChem (IF 3.975) Pub Date : 2020-01-20
    Yong Li; Rui Guo; Yanting Sun; Yong Wang; Wen Liu; Haijuan Pei; Hongbing Zhao; Jiujun Zhang; Daixin Ye; Jingying Xie; Jilie Kong

    Cobalt sulfide (CoS 2 ) is a promising anode material for high‐performance sodium ion batteries (SIBs) because of its low cost, excellent electrical conductivity and high theoretical capacity. The practical implementation of CoS 2 anode, however, is still hindered by fast capacity decay and low power density caused by its huge volume expansion during the charging/discharging process. Herein, we developed a low‐cost, facile and large‐scale method to fabricate nitrogen‐doped carbon layers‐constraint structured CoS 2 /carbon nanotubes (NC@CoS 2 @CNTs) hybrid with a novel morphology for high‐performance SIBs. The hybrid electrode has reversible specific capacities of 669 and 334 mAh g ‐1 at the current densities of 200 mA g ‐1 and 5000 mA g ‐1 , respectively, and a unprecedented cycling stability of ~0.014% capacity decay per cycle over 1000 cycles at 3000 mA g ‐1 . The balanced high electrochemical performance for the hybrid electrode can be attributed to the synergetic effect among the CoS 2 nanoparticles, N‐doped carbon coating and in‐situ growing CNTs. The results demonstrate that the CoS 2 can be well utilized with N‐doped carbon/carbon nanotubes hybrid material structure, which provide a facile approach to realize excellent performance for practical applications.

    更新日期:2020-01-21
  • The Influence of Quantum Dot Surface on Electrochemical DNA Sensing Mechanism
    ChemElectroChem (IF 3.975) Pub Date : 2020-01-20
    Xolile Fuku; Priscilla Baker; Emmanuel Iwuoha

    Due to their high surface‐to‐volume ratio, electro‐catalytic activity, biocompatibility and novel electron transport properties, quantum dot (QD) are highly attractive materials for ultra‐sensitive detection of biological macromolecules via bio‐electronic devices. In this study a QD‐based genosensor was developed in which Ga 2 Te 3 ‐based QD was synthesised using a novel aqueous solution approach by mixing 3‐mercaptosuccinic acid (3MSA)‐capped gallium metal precursor with reduced tellurium metal. The results gave original understandings relating to the active material involved in the probe DNA sensing mechanism. The morphological and structural characterisation of the QD was investigated prior to their utilization in DNA sensor construction. High resolution TEM (HR‐TEM) and atomic force microscopy (AFM) images confirmed the spherical and crystalline nature of the QD while X‐ray Photoelectron Spectroscopy (XPS) and X‐ray diffraction (XRD) analysis were able to confirm the oxidation states and formation of the prepared QD. UV‐VIS was capable to find the optical band gap energy and the photostability of the QD. The resultant Ga 2 Te 3 QD together with metal ions confirmed their use for DNA signal detection through their DNA binding mechanism in the genosensor construction. Genosensing in Cs + and Li + ions exhibited higher sensitivity (2.74 ‐ 3.69 μA ng ‐1 mL) and very low detection limits (0.4 pg mL ‐1 ) with the linear dynamic range of 0.1 ‐ 1 ng mL ‐1 .

    更新日期:2020-01-21
  • A microfluidic system with an extended‐gate type organic transistor for real‐time glucose monitoring
    ChemElectroChem (IF 3.975) Pub Date : 2020-01-19
    Pierre Didier; Nicolas Lobato-Dauzier; Nicolas Clément; Anthony J. Genot; Yui Sasaki; Éric Leclerc; Tsukuru Minamiki; Yasuyuki Sakai; Teruo Fujii; Tsuyoshi Minami

    Organic field‐effect transistors (OFETs) can be potentially employed to monitor cell activities for healthcare and medical treatment, because of their attractive properties such as ease of use, flexibility, and low‐cost manufacturing processes. Although current OFET‐based sensors are suitable for point‐of‐care testing, the establishment of real‐time monitoring methods is highly demanded to continuously monitor health conditions and/or biological cell activities. In this regard, we herein propose a microfluidic platform integrated with an extended‐gate type OFET for real‐time glucose monitoring. The detection mechanism of glucose depends on an artificial receptor phenylboronic acid and its boronate esterification. After the optimization of microfluidics for the OFET‐based sensor, we applied it to monitor glucose consumption and release in a model of pseudo liver cells. Random increase or decrease in changes of the glucose concentrations has been reproducibly monitored.

    更新日期:2020-01-21
  • Tailor‐designed porous catalysts: Ni‐doped Cu/Cu2O foams for efficient glycerol electro‐oxidation
    ChemElectroChem (IF 3.975) Pub Date : 2020-01-19
    Gumaa A M ElNagar; Mohamed R Rizk; Muhammad G Abd El-Moghny; Amina Mazhar; Mohamed S El-Deab

    Herein, Cu/Cu 2 O foams with dendritic‐like structures were electrodeposited atop smooth Cu electrode by dynamic hydrogen bubbles technique, and then were used as efficient electrocatalysts for glycerol electrooxidation. The morphology, structure, and composition of the as‐prepared Cu/Cu 2 O foams were tuned by additives (e.g, KCl and NiCl 2 ) in the copper deposition bath to maximize their electrocatalytic performance towards glycerol electrooxidation. The as‐synthesized Cu/Cu 2 O foams showed superior electrocatalytic activity towards glycerol oxidation reaction, as demonstrated by the significant negative shift in the onset potential (~400 mV) together with up to 6 times higher oxidation current, compared to the Cu/Cu 2 O non‐porous film with the same loading. The performance of these foams was further improved via introducing minute amounts of either Ni 2+ and/or Cl ‐ ions. These additives resulted in a significant change in the structure and shape of the electrodeposited Cu/Cu 2 O textures with a concurrent increase in their roughness. Material and electrochemical characterization (e.g., SEM, XRD, XPS, LSC and CV) techniques were used to link the observed enhancements into the morphology, composition, and structure of the as‐synthesized Cu/Cu 2 O foam materials.

    更新日期:2020-01-21
  • Electrochemical reduction of CO2 into C1 and C2 hydrocarbons using dendritic Cu and Cu2O electrodes
    ChemElectroChem (IF 3.975) Pub Date : 2020-01-19
    Muhammad Tajmeel Feroze; Syed Kamran Sami; Dulyawat Doonyapisut; Byeongkyu Kim; Chan-Hwa Chung

    Electroreduction of carbon dioxide to C1 and C2 hydrocarbons has been emerged as an efficient way to utilize carbon dioxide and maintain the broken carbon‐cycle in the environment. The copper is a promising catalyst for such a purpose. The selectivity and stability of hydrocarbon production is still a challenge. Here we propose a simple one‐step electro‐deposition of copper followed by annealing in air, in which the dendritic structures of Cu and Cu 2 O electrodes have been prepared, to enhance the copper‐electrode properties in terms of morphology, selectivity, stability, and electrochemical performance. The selectivity of ethylene using modified dendritic Cu 2 O electrodes remains stable (from 19.21 % to 18.01 %) after the course of over 10 hours by applying a constant potential of ‐1.4V. Our finding suggests a promising lead for the design of practical electrode catalytic electrodes for the fuel synthesis with electrochemical CO 2 reduction.

    更新日期:2020-01-21
  • Spinel Li4Mn5O12 as Novel 2.0 V Insertion Materials for Mg‐based Hybrid Ion Batteries
    ChemElectroChem (IF 3.975) Pub Date : 2020-01-18
    Yuan Cen; Yuping Liu; Yan Zhou; Pengfei Jiang; Jiahong Hu; Qin Xiang; Bingbing Hu; Chuanlan Xu; Danmei Yu; Changguo Chen

    With the increasing demand for electrical energy storage, a new Mg‐Li hybrid battery with Mg anode is regarded as promising candidate because of low cost, high volumetric capacity and dendrite‐free nature for Mg anode. Nevertheless, the characteristics of low operation voltage and low energy density for Mg‐Li hybrid batteries hinders up their widespread applications owing to limited reversible cathodes. To overcome these issues, highly reversible fast Li + insertion cathode with high‐voltage is an effective strategy for high‐energy density Mg‐Li hybrid batteries. Herein, we develop a 2 V high‐voltage spinel Li 4 Mn 5 O 12 cathode material with unique nano/microsphere via a novel low temperature method, offering short Li diffusion path and sufficient transport channels for electrolyte penetration into the electrode. For the first time, we demonstrates the feasibility of the spinel Li 4 Mn 5 O 12 nano/microsphere with hierarchical architecture as cathode for 2 V hybrid Mg‐Li batteries It exhibits a reversible specific capacity of 155 mAh g ‐1 and a long discharge voltage platform exceeding 2.0 V (vs. Mg / Mg 2+ ) coupled with high energy density of 326 Wh kg ‐1 at a current density of 0.1 C (1 C= 163 mA g ‐1 ). Our results pave the way of constructing new hybrid Mg‐Li batteries with high‐voltage and high‐energy density.

    更新日期:2020-01-21
  • A Flexible Quasi‐Solid‐State Composite Electrolyte Membrane Derived from Metal‐Organic Framework for Lithium Metal Batteries
    ChemElectroChem (IF 3.975) Pub Date : 2020-01-17
    Chunwen Sun; Li Liu

    In this work, we developed a new kind of flexible Li ion conductor membrane consisting of PVDF‐HFP matrix and ionic liquid absorbed in metal‐organic framework (MOF) particles. This composite membrane facilitates a homogeneous Li‐ion flux and exhibits excellent ionic conductivity of about 4.3×10‐4 S cm‐1 at room temperature, wide electrochemical window of 4.8 V (vs. Li+/Li), good thermal stability and flexibility. The quasi‐solid‐state lithium metal battery assembled with the composite electrolyte membrane, Li metal anode and composite cathode shows low interface impedance and reversible discharge capacity of 149 mAh g‐1 within 300 cycles at 0.1 C. This new kind quasi‐solid‐state electrolyte membrane demonstrates a promising candidate for solid‐state lithium‐metal batteries with high energy density.

    更新日期:2020-01-21
  • Reduction of nitrate and nitrite in Iberian dry cured loins and its effects during drying process
    Meat Sci. (IF 3.483) Pub Date : 2020-01-18
    N. Higuero; I. Moreno; G. Lavado; M.C. Vidal-Aragón; R. Cava

    Four batches of Iberian dry-cured loins were manufactured with reduced ingoing amounts of both nitrate and nitrate: 150 mg/kg, 75 mg/kg, 37.5 mg/kg and 0 mg/kg. The effect of reducing or removing nitrate and nitrite and time of drying on physicochemical parameters (moisture, pH, water activity, chloride and residual nitrate and nitrite contents), instrumental colour and nitrosylmyoglobin content, lipid and protein oxidation and on microbiological counts (L. monocytogenes, aerobic mesophilic bacteria and moulds and yeast counts) were investigated. Lipid oxidation increased during the drying process being higher for non-added NO3−/NO2−, meanwhile protein oxidation affected also those with 37.5 and 75 mg/kg of NO3−/NO2− added. The removal of these additives affected instrumental colour coordinates and total colour changes showed that the variation of coloration would be perceptible by the consumer. Nitrosylmyoglobin content was significantly higher for NO3−/NO2− added loins. Reduced levels of these additives up to 37.5 mg/kg did not show significant effects on their physico-chemical, microbiological and colour.

    更新日期:2020-01-21
  • Recent progress in ligand photorelease reaction mechanisms: Theoretical insights focusing on Ru(II) 3MC states
    Coordin. Chem. Rev. (IF 13.476) Pub Date : 2020-01-20
    Adrien Soupart; Fabienne Alary; Jean-Louis Heully; Paul I.P. Elliott; Isabelle M. Dixon

    The elucidation of reaction mechanisms taking place in the excited state is a current challenge for experimental and theoretical chemists. Ru(II) complexes have a long history for photophysics, and there is currently an increasing interest in their photochemistry. Ru(II) complexes provide a vast field of exploration, whether for synthetic purposes, to trigger molecular motions or to release biologically active components. The excited states involved, especially those of MLCT and MC character, are key to the rationalization of their photophysical and photochemical properties. This review focuses on the recent progress in the latter field through several case studies: i) the archetypes [Ru(bpy)3]2+ and [Ru(tpy)2]2+ first serve for the validation of the theoretical methods we are using; ii) then the study of photorelease of a monodentate ligand provides us with novel mechanistic hypotheses; iii) one step further, studying the photorelease mechanism of a bidentate ligand provides us with novel 3MC states of peculiar flattened geometry; iv) finally, returning to [Ru(bpy)3]2+ itself, we will show that the existence of these states can be generalized and probably represent a major player in the description of photoreactivity mechanisms, for ruthenium and possibly several other transition metals.

    更新日期:2020-01-21
  • Luminescent phosphine gold(I) alkynyl complexes. Highlights from 2010 to 2018
    Coordin. Chem. Rev. (IF 13.476) Pub Date : 2020-01-17
    Marc Pujadas; Laura Rodríguez
    更新日期:2020-01-21
  • Aerobic oxidation of alcohol by model complexes relevant to metal site galactose oxidase: role of copper(I) intermediate, evidence for the generation of end-on copper(II)–OOH species and catalytic promiscuity for oxidation of benzyl alcohol, catechol and o -aminophenol
    Transit. Met. Chem. (IF 1.016) Pub Date : 2020-01-20
    Ashish Kumar Dhara, Kapil Kumar, Sheela Kumari, U. P. Singh, Kaushik Ghosh

    Abstract Tridentate ligands having meridional NNO donor centres were designed and synthesized mimicking the copper coordination in the metal site of galactose oxidase enzyme. Mononuclear copper complexes [Cu(L1)Cl] (1) (L1H = (E)-2-((2-phenyl-2-(pyridin-2-yl)hydrazono)methyl)phenol), [Cu(L2)Cl] (2) (L2H = (E)-4-methyl-2-((2-phenyl-2-(pyridin-2-yl)hydrazono)methyl)phenol), [Cu(L3)Cl] (3) (L3H = (E)-1-((2-phenyl-2-(pyridin-2-yl)hydrazono)methyl)naphthalen-2-ol), [Cu(L4)Cl] (4) (L4H = (E)-2-((2-phenyl-2-(pyridin-2-yl)hydrazono)methyl)phenol), [Cu(L5)Cl] (5) (L5H = (E)-2-((2-phenyl-2-(pyridin-2-yl)hydrazono)methyl)phenol), and [Cu(L6)Cl] (6) (L6H = (E)-2,4-di-tert-butyl-6-(((pyridin-2-ylmethyl)imino)methyl)phenol) were synthesized and characterized. Molecular structure of complex 3 was determined by single crystal X-ray crystallography. Phenoxyl radical complexes were generated in solution via chemical oxidation using ceric ammonium nitrate (CAN), and the radical complexes were characterized by UV–Vis–NIR spectrophotometer. DFT calculations were performed at B3LYP level to optimize the ground-state molecular geometry of the complexes. To understand the electronic properties and absorption spectra of the complexes, TD-DFT calculations were executed for phenoxyl radical complexes considering triplet as well as singlet spin states. Alcohol oxidation was examined utilizing complexes 1–6 as catalyst, and importance of stabilization of Cu(I) intermediate was scrutinized and generation of Cu(II)–OOH was examined. Catalytic promiscuity for catechol oxidase and phenoxazinone synthase activity by complexes (1–5) was investigated. Theoretical calculations and ESI–MS spectral studies were performed during oxidation chemistry of benzyl alcohol, catechol and o-amino phenol to support the proposed mechanism.

    更新日期:2020-01-21
  • Exploring removal of formaldehyde at room temperature over Cr- and Zn-modified Co 3 O 4 catalyst prepared by hydrothermal method
    Res. Chem. Intermed. (IF 2.064) Pub Date : 2020-01-20
    Junliang Xie, Mianwu Meng, Zhihao Lin, Hua Ding, Jianhua Chen, Siyu Huang, Zhenming Zhou

    Abstract The metal-modified Co3O4 sample (metal: Zn or Cr, Zn and Cr) was prepared through hydrothermal approach, and applied in low concentration of HCHO removal under room temperature. The Cr/Zn/Co3O4 exhibited the best formaldehyde removal activity and stability. The effect of dopants on the physicochemical properties of the Co3O4 samples was characterized by X-ray diffraction, Raman, N2 adsorption–desorption, scanning electron microscopy, transmission electron microscopy, thermogravimetric (TG-DTG) and X-ray photoelectron spectroscopy, resulting that the Cr/Zn/Co3O4 sample possessed the optimal specific surface area (177.53 m2/g, 3.4 times that of pure Co3O4). Meanwhile, Cr and Zn incorporated into Co3O4 lattice simultaneously and promoted the formation of defects, which is the prerequisite for increasing the reactive oxygen species of Cr/Zn/Co3O4. In addition, Cr6+/Cr3+ ion pairs in the sample could be an important role in the removal of formaldehyde. It is concluded that the ideal HCHO removal performance and stability of Cr/Zn/Co3O4 were associated with its high vacancy oxygen content, excellent specific surface area and the promotion of Cr6+/Cr3+ ion pairs. Graphic abstract

    更新日期:2020-01-21
  • Enzyme-induced Fenton reaction coupling oxidation of o-phenylenediamine for sensitive and specific immunoassay
    J. Solid State Electr. (IF 2.531) Pub Date : 2020-01-20
    Bingqian Liu, Weiping Shi, Yani Yang, Jie Cai

    Abstract In this paper, a simple and feasible immunoassay protocol with signal amplification for sensitive determination of alpha fetoprotein (AFP, used as a model) by using new enzyme-induced Fenton reaction (EIFR) accompanying the oxidation of o-phenylenediamine (OPD) system. We discovered that glucose oxidase (GOx) has the ability to stimulate in situ Fenton reaction coupling the oxidation of OPD. GOx-catalyze of glucose results in the formation of hydrogen peroxide (H2O2). It can catalytically oxidize Fe2+to Fe3+, meanwhile producing hydroxyl radicals (•OH). The latter effectively initiated the catalytic oxidation of o-phenylenediamine (OPD) to 2,2-aminoazobenzene (DAP), resulting in the production of an electrochemical signal. On the basis of EIFR-OPD system, a new immunoassay protocol with GOx/anti-pAb2-conjugated gold nanoparticle (Ab2-AuNP-GOx) detection antibody can be designed for the detection of target AFP on capture antibody–functionalized transparent 96-well polystyrene microplate, monitored by recording the current peak of the generated DAP. The electrochemical current shows to be positively correlated with the concentration of target AFP. Under optimal conditions, the proposed assay exhibited good electrochemical responses for detecting target AFP in the range of 1.0 pg mL−1 to 100 ng mL−1 with a detection limit (LOD) of 0.5 pg mL−1 (0.5 ppt) estimated at the 3Sblank level. Additionally, the precision, reproducibility, specificity, and method accuracy were also investigated with acceptable results. Importantly, the EIFR-OPD system can be further extended for the determination of other protein or biomarkers by controlling the specific recognition system (antibody or aptamer).

    更新日期:2020-01-21
  • Performance comparison with different methods for ethanol/O 2 biofuel cell based on NAD + cofactor immobilized and activated by two types of carbon nanoparticles
    J. Solid State Electr. (IF 2.531) Pub Date : 2020-01-18
    Djamel Selloum, Vincent Techer, Abdellah Henni, Sophie Tingry, Marc Cretin, Christophe Innocent

    Abstract Biofuel cells are an attractive alternative to conventional fuel cells, because they use biological catalysts. We report in this article the construction of an ethanol/O2 enzymatic biofuel cell. In the first time, the performance comparison with different methods for ethanol/O2 biofuel cell has been study. Alcohol dehydrogenase, a nicotinamide adenine dinucleotide (NAD)-dependent enzyme, is immobilized with NAD+, diaphorase, and vitamin K3 (VK3) on the electrode. The oxygen is reduced at the cathode with laccase and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonate) (ABTS). The performances of the electrodes are improved thanks to addition of carbon powder (KS6 and Super P® carbon). The benefit of the carbon particles with higher surface porosity was explained by the high-porous structure that offered a closer proximity to the reactive species and improved diffusion of ethanol and oxygen within the enzyme films. Efficiency of immobilization of NAD+ cofactor has been also demonstrated. We have shown the effect of multi-enzymatic reaction at the anode on the storage and operational stability. A high open-circuit potential has been recorded 1.02 V, demonstrating the benefit of NAD+ immobilization with maximal power density of 300 μW cm−2. Chronoamperometric measurements show a current density of 90 μA cm−2 during 20 h demonstrating the operational stability of the ethanol biofuel cell based on NAD+ cofactor immobilization.

    更新日期:2020-01-21
  • Hybrids of LiMn 2 O 4 nanoparticles anchored on carbon nanotubes/graphene sheets as long-cycle-life cathode material for rechargeable hybrid aqueous batteries
    J. Solid State Electr. (IF 2.531) Pub Date : 2020-01-18
    Guanghui Yuan, Min Geng, Ping Zhang, Baobao Li

    Abstract A hybrid LiMn2O4-graphene-carbon nanotubes (LMO-GN-CNT) material is synthesized successfully by a facile hydrothermal method. The 15-nm-nanosized LiMn2O4 (LMO) particles anchor uniformly in the cross-linked conductive graphene (GN) and carbon nanotubes (CNT) matrix in the LMO-GN-CNT composite. Rechargeable hybrid aqueous batteries (ReHABs) are assembled by using LMO-based materials as cathodes and zinc metal as anodes. Galvanostatic charging/discharging cycles of the LMO-GN-CNT composite are performed in rechargeable hybrid aqueous batteries (ReHABs) in comparison of LMO-GN composite and pristine LMO material. Electrochemical measurements indicate that the LMO-GN-CNT composite exhibits superior rate capability and cycle ability. The initial discharge capacity of 129 and 100 mAh g−1 can be delivered at 0.2 and 5.0 C. The discharge capacity is still above 93 mAh g−1, and capacity retention of over 82.1% is obtained after 600 cycles at 2.0 C. The satisfactory electrochemical properties can be ascribed to the little aggregation and good dispersion of the nanosized LMO particles and the introduction of GN and CNT, which can enhance the conductivity, shorten the diffusion length of electrolyte, and provide a large specific surface area for lithium storage.

    更新日期:2020-01-21
  • Facilitating oxygen reduction by silver nanoparticles on lanthanum strontium ferrite cathode
    J. Solid State Electr. (IF 2.531) Pub Date : 2020-01-18
    Rokas Sažinas, Kjeld Bøhm Andersen, Kent Kammer Hansen

    Abstract Single-phase silver (Ag)-doped La0.85-xSr0.15AgxFeO3-δ (x = 0–0.05) materials (LSAF) were synthesized by wet synthesis route and calcined at 800 °C in air. The materials exhibited no thermal degradation in Ar and synthetic air below sintering temperature at 1200 °C of the cathode for solid oxide fuel cells. Exsolution of Ag nanoparticles from the perovskite lattice at 420 °C in reducing 5% H2/N2 was investigated, and electrocatalytic activity of the cathodes towards oxygen reduction reaction for solid oxide fuel cells was demonstrated. Scanning electron microscopy confirmed exsolution of Ag nanoparticles with increased effective surface area, and the particles were distributed with a good contact on the surface of the perovskite. Electrochemical performance of novel materials was tested and compared. Enhanced cathode with Ag nanoparticles revealed the area specific resistance of 0.23 and 0.15 Ω cm2 at 800 °C in 20% O2/N2 before and after Ag exsolution, respectively. The area specific resistance of the cathode decreased with Ag exsolution, operation temperature, and increasing oxygen partial pressure.

    更新日期:2020-01-21
  • Spectrophotometric Analysis of Ternary Uranyl Systems to Replace Tri- N -butyl Phosphate (TBP) in Used Fuel Reprocessing
    J. Solut. Chem. (IF 1.039) Pub Date : 2020-01-20
    Adam J. Canner, Laurence M. Harwood, Joseph Cowell, Jasraj S. Babra, Solomon F. Brown, Mark D. Ogden

    Abstract In this report, the interaction of monoamide/diamide and monoamide/diglycolamide mixtures with \({\text{UO}}_{2}^{2 + }\) are investigated in pH = 1 methanolic nitric acid media. These monoamides include N,N-dimethylacetamide (DMAA), N,N-diethylacetamide (DEAA), N,N-dibutylacetamide (DBAA) and N,N-dibutylbutanamide (DBBA). N,N,N′N′-tetraethylmalonamide (TEMA) and N,N,N′,N′-tetraethyldiglycolamide (TEDGA), which were chosen as model diamides and diglycolamides, respectively. Complex stability constants for each ligand were modelled using the Stability Quotients Using Absorbance Data program using UV–visible data. Complex stoichiometry of ligand mixtures was determined using Job plots and UV–Vis spectrometry. Monoamides were confirmed to produce only disolvate complexes with \({\text{UO}}_{2}^{2 + }\) in solution. The log10(K) values for monoamides were found to be independent of amine-side chain length, but were slightly dependent on the carbonyl-side chain length. TEDGA was found to produce multiple uranyl complexes in solution. Job plot data indicated that the uranyl cation strongly prefers to bond either only with the monoamide or diamide in ternary monoamide–diamide–UO2 systems. Monoamide–diglycolamide–UO2 systems were more complicated, with Job plot data indicating the potential for multiple ternary species being present is dependent on the monoamide structure.

    更新日期:2020-01-21
  • Theoretical assessment of antioxidant property of polyproponoid and its derivatives
    Struct. Chem. (IF 1.624) Pub Date : 2020-01-20
    K. Anbazhakan, K. Sadasivam, R. Praveena, Guillermo Salgado, Wilson Cardona, Daniel Glossman- Mitnik, Lorena Gerli

    Abstract Derivatives of parent molecules possess similar structural activity which makes them to be the topic of equal interest. In the present work, a naturally occurring acid eugenol and its co derivatives allyl-2-methoxy-4-nitrophenol and 5-Allyl-3-nitrobenzene-1,2-diol are theoretically investigated for their antioxidant role using density functional theory (DFT). Becke’s exchange correlation functional B3LYP and Minnesota functional M062X along with the basis set 6-311++G(d,p) are used to investigate the structural property through geometry optimization, frontier molecular orbital analysis, electrostatic potential analysis, and molecular descriptive parameters. Electron donating capability of the molecules is analyzed using frontier molecular orbital analysis and molecular descriptors. Molecular surface potential analysis facilitated to locate highest and lowest potential regions in these molecules. Hydrogen atom abstraction property (radical scavenging property) of the molecules is studied with the help of hydrogen atom transfer mechanism.

    更新日期:2020-01-21
Contents have been reproduced by permission of the publishers.
导出
全部期刊列表>>
2020新春特辑
限时免费阅读临床医学内容
ACS材料视界
科学报告最新纳米科学与技术研究
清华大学化学系段昊泓
自然科研论文编辑服务
中国科学院大学楚甲祥
上海纽约大学William Glover
中国科学院化学研究所
课题组网站
X-MOL
北京大学分子工程苏南研究院
华东师范大学分子机器及功能材料
中山大学化学工程与技术学院
试剂库存
天合科研
down
wechat
bug