A comparative study on the role of urea in controlling the morphology of calcium‐bismuth (Ca₅Bi₃) bimetallic nanoparticles is carried out. Calcium‐bismuth bimetallic nanoparticles are synthesized in the presence and absence of urea using the solvothermal method. The morphology of the synthesized products is analyzed by scanning electron microscopy. The composition of the product is analyzed by energy‐dispersive X‐ray spectroscopic and X‐ray diffraction (XRD) analyses. Reitveld refinements are performed on the XRD data, and lattice parameters are optimized. Reitveld‐refined parameters are used to construct the structural model of the calcium‐bismuth product. The formation mechanism of needle like particles from an orthorhombic unit cell is also proposed. The degradation of Congo red dye is catalyzed by synthesized Ca₅Bi₃ bimetallic nanoneedles in an aqueous medium. The effect of catalyst dose on the apparent rate constant (k_app) of degradation is studied and compared with literature. Ca₅Bi₃ bimetallic nanoneedles are also used as an additive in commercial diesel obtained from Pakistan State Oil, Limited. The effect of an additive dose on the calorific value of diesel is studied. How the Ca₅Bi₃ additive influenced other fuel quality parameters such as flash point, fire point, pour point, cloud point, kinematic viscosity, and specific gravity is also studied.

中文翻译：

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尿素在鸡蛋壳中形态控制合成钙铋双金属纳米颗粒中的作用及其催化和燃料添加剂的应用研究

尿素在控制钙铋（Ca ₅ Bi _3）形态中作用的比较研究）进行双金属纳米粒子。钙铋双金属纳米粒子是通过溶剂热法在存在和不存在尿素的情况下合成的。通过扫描电子显微镜分析合成产物的形态。通过能量色散X射线光谱和X射线衍射（XRD）分析来分析产品的成分。对XRD数据执行Reitveld改进，并优化晶格参数。Reitveld改进的参数用于构建钙铋产品的结构模型。还提出了正交晶胞中针状颗粒的形成机理。合成的Ca ₅ Bi ₃催化刚果红染料的降解水性介质中的双金属纳米针。研究了催化剂用量对降解的表观速率常数（k _app）的影响，并与文献进行了比较。Ca ₅ Bi ₃双金属纳米针还用作从巴基斯坦国家石油有限公司（Pakistan State Oil，Limited）获得的商用柴油中的添加剂。研究了添加剂剂量对柴油热值的影响。还研究了Ca ₅ Bi ₃添加剂如何影响其他燃料质量参数，例如闪点，着火点，倾点，浊点，运动粘度和比重。