Traditional approaches for corn stover utilization create an inhomogeneous, whole plant mixture that does not achieve performance and cost targets for biofuel production. The improvement of conversion performance will require one to gain a fundamental understanding of the inherent cellular structure and ash content in the process. This study investigated cellular structure and inorganic species contents with scanning electron microscopy (SEM), advanced energy dispersive X-ray spectroscopy (EDS), and wet analytical chemistry methods. These techniques provided a complementary means to understand variability within the dynamic cell walls and the distributions of inorganic species at the anatomical and tissue scales for various corn stover fractions. Material properties were investigated for bales from in-field storage scenarios ranging from mild to severe biological degradation. Results show that stem, cob, and leaf tissues all maintained cell wall and surface structure integrity after mild biological degradation. However, severe degradation (with spontaneous heating) caused remarkable structural distortion and cell wall shrinkage for all tissue types. Inorganic species quantitation data shows that three fractions of severe degradation have slightly reduced total ash, 4.91% vs 3.92% for cobs, 7.28% vs 5.98% for stems, and 14.21% vs 13.07% for leaves. Silica contents also decreased (2.67% vs 1.83% for cobs, 3.60% vs 2.89% for stems, and 9.72% vs 8.48% for leaves), likely due to the loss of extrinsic inorganic species. SEM-EDS inorganic species mapping of stems demonstrated that severe biological degradation caused the translocation of the dominant silicon elements from pith to rind tissue as well as a reduction of potassium in the stem. These findings offer detailed knowledge of feedstock variability at the anatomical tissue level that can be used to inform the development of advanced processing strategies. Innovative storage and selective fractionation processes have the potential to manage low-quality fractions/tissues and remove unfavorable inorganic species for efficient conversion of corn stover as well as other lignocellulosic biomass.

中文翻译：

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收获和储存的玉米秸秆级分中动态细胞壁结构和无机物种变异的表征和定位与生物降解的关系

玉米秸秆利用的传统方法会产生不均匀的整个植物混合物，无法实现生物燃料生产的性能和成本目标。转化性能的提高将需要人们对过程中固有的细胞结构和灰分含量有基本的了解。这项研究通过扫描电子显微镜（SEM），先进的能量色散X射线光谱（EDS）和湿法分析化学方法研究了细胞结构和无机物含量。这些技术提供了一种补充手段，以了解动态细胞壁内的变异性以及各种玉米秸秆级分在解剖学和组织尺度上的无机物种类分布。对从轻度到严重的生物降解范围内的现场存储情况下的棉包的材料特性进行了研究。结果表明，轻度生物降解后，茎，穗轴和叶组织都保持了细胞壁和表面结构的完整性。但是，严重的降解（自发加热）会引起所有组织类型的明显结构变形和细胞壁收缩。无机物种的定量数据显示，严重降解的三部分降低了总灰分，玉米芯的灰分分别为4.91％和3.92％，茎的灰分分别为7.28％和5.98％和14.21％和13.07％。二氧化硅含量也下降了（玉米芯的含量为2.67％vs. 1.83％，茎的含量为3.60％vs. 2.89％，叶片的含量为9.72％vs 8.48％），这可能是由于非本征无机物种的流失所致。茎的SEM-EDS无机物种图谱表明，严重的生物降解导致主要的硅元素从髓转移到果皮组织，并使茎中的钾减少。这些发现提供了在解剖组织水平上原料变异性的详细知识，可用于指导先进加工策略的发展。创新的存储和选择性分级分离工艺具有管理低质量的分级分离/组织和去除不利的无机物质的潜力，从而可以有效地转化玉米秸秆和其他木质纤维素生物质。这些发现提供了在解剖组织水平上原料变异性的详细知识，可用于指导先进加工策略的发展。创新的存储和选择性分级分离工艺具有管理低质量的分级分离/组织和去除不利的无机物质的潜力，从而可以有效地转化玉米秸秆和其他木质纤维素生物质。这些发现提供了在解剖组织水平上原料变异性的详细知识，可用于指导先进加工策略的发展。创新的存储和选择性分级分离工艺具有管理低质量的分级分离/组织和去除不利的无机物质的潜力，从而可以有效地转化玉米秸秆和其他木质纤维素生物质。