An Analytical Study of the Economic Condition of Jews in Fatimid Egypt

This study examines the economic conditions of Jews in Fatimid Egypt from the 10th to 12th centuries CE. Through an analysis of primary sources, the study provides a nuanced understanding of the economic and social factors that affected the Jewish community during this period. The study argues that while Jews in Fatimid Egypt enjoyed certain economic privileges such as their involvement in international trade networks and their exemption from some taxes, they also faced some social and political restrictions, including forced conversion and discriminatory laws in the era of some Fatimid rulers. Despite these challenges, the Jewish community in Fatimid Egypt demonstrated resilience and adaptability, developing a range of economic strategies to maintain their livelihoods and build social networks. These strategies included investment in trade and finance, engagement with the wider Muslim society, and the development of communal institutions. The study highlights the complexity of Jewish economic life in medieval Egypt, challenging simplistic assumptions about the economic conditions of minority groups in pre-modern societies.

Multidimensional Process Models for Seeded Batch Crystallization

This contribution focuses on the modeling and numerical approxima- tion of population balance models describing batch and polymorphic crystallization processes. Such processes have wide range applica- tions inne chemicals, pharmaceutical, minerals, and food indus- tries. Di erent numerical techniques are employed for solving these models in one and two property coordinates. The space-time CE/SE method and the semi-discrete upwindnite volume schemes are de- rived and implemented to solve the batch crystallization models with nes dissolution. Thene dissolution reduces undesirable small crys- tals and improves the quality of a product. A delay in the recycle pipe is also included in the model. Apart from the above mentioned methods, a new numerical technique is introduced to solve a model describing polymorphic crystallization of L-glutamic acid. The sug- gested technique employs together the method of characteristics and Duhamel''s principle to approximate the considered model e ciently and accurately. This technique has capability to produce accurate results on coarse meshes and no mesh re nement technique is needed for further improvement in the results. Furthermore, an alternative bivariate quadrature method of moments (QMOM) is developed for solving two-dimensional batch crystallization model involving crys- tals growth, nucleation, aggregation, and small nuclei dissolution in an external loop. The quadrature points and weights are obtained by using the orthogonal polynomials of lower order moments. Several case studies are carried out. The numerical computations demonstrate the eficiency, accuracy, and robustness of the proposed schemes. The results agree with the experimental predictions and could be used for process design and optimization.