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81.
Andreas Bück Günter Klaunick Jitendra Kumar Mirko Peglow Evangelos Tsotsas 《American Institute of Chemical Engineers》2012,58(8):2309-2319
Results of application of pseudospectral methods, also known as spectral collocation methods, to practical particulate processes including growth, nucleation, aggregation, and breakage are presented. For growth‐dominated processes, a considerable reduction in model dimension can be achieved; for pure aggregation and breakage they form a viable option. To handle problems that include aggregation, breakage, and growth phenomena simultaneously, we introduce a hybrid algorithm combining the advantages of spectral methods and cell average or fixed pivot methods for aggregation and breakage. Results are shown for analytical examples as well as real processes taken from the fields of granulation and crystallization. © 2011 American Institute of Chemical Engineers AIChE J, 58: 2309–2319, 2012 相似文献
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83.
The investigation of a single pit/defect evolution due to localized corrosion that is commonly observed in a wide range of aluminum alloys is reported. Electrochemical experiments, microscopy and computations were used to predict stresses around a single pit/defect. It was observed that the pit/defect profile changing its shape from slightly conical to more hemispherical shape with increasing corrosion time. Also, stress distribution and levels vary non-linearly around a single pit/defect. The results also indicate that the evolution of these pits/defects may lead to nucleation of a crack over time, which can be predicted from these stresses. 相似文献
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85.
The Density of States and the Transport Effective Mass in a Highly Oriented Semiconducting Polymer: Electronic Delocalization in 1D 下载免费PDF全文
86.
Identification of lead compounds with higher molecular weight and lower aqueous solubility has become increasingly prevalent with the advent of high throughput screening. Poor aqueous solubility of these lipophilic compounds can drastically affect the dissolution rate and subsequently the drug absorbed in the systemic circulation, imposing a significant burden of time and money during drug development process. Various pre-formulation and formulation strategies have been applied in the past that can improve the aqueous solubility of lipophilic compounds by manipulating either the crystal lattice properties or the activity coefficient of a solute in solution or both, if possible. However, despite various strategies available in the armor of formulation scientist, solubility issue still remains an overriding problem in the drug development process. It is perhaps due to the insufficient conceptual understanding of solubility and dissolution phenomenon that hinders the judgment in selecting suitable strategy for improving aqueous solubility and/or dissolution rate. This article, therefore, focuses on (i) revisiting the theoretical and mathematical concepts associated with solubility and dissolution, (ii) their application in making rationale decision for selecting suitable pre-formulation and formulation strategies and (iii) the relevant research performed in this field in past decade. 相似文献
87.
Parinita Agarwal Mitali Dabi Mamali Das Khantika Patel Pradeep K. Agarwal 《The International journal of environmental studies》2013,70(4):624-630
Jatropha curcas is an important non feed crop, increasingly important as a biofuel crop. It is hardy and resistant to different stress conditions in the field. In the wastelands of Gujarat (India), it is being grown for land reclamation and for socio-economic benefits. The long coastline in this state also promotes the growth of a large number of halophytes. Exploiting the genetic resource of Jatropha and halophytes for drought and salt-induced gene is an important area of research. For the isolation of genes and to study the molecular mechanism a good qualitative and quantitative RNA is a prerequisite. Jatropha leaves have latex, and therefore isolating RNA using guanidine thiocyanate or cetyltrimethylammonium bromide did not yield desirable quality of RNA. This paper reports a very simple and economical protocol for the isolation of good quality RNA from Jatropha and a few halophytes. The sodium dodecyl sulphate was used as a detergent for lysis of plant cells in the extraction buffer along with bentonite, which inhibits the ribonuclease’s activity. The addition of water saturated phenol in mortar-pestle, during grinding, facilitated better homogenisation of the tissues. Absolute RNA precipitation was obtained with the help of 2-butoxyethanol. Further this RNA was used successfully in preparation of complementary DNA and subsequently used for gene isolation. 相似文献
88.
Popat Y. Orlandi M. Gupta S. Bazzanella N. Pillai S. Patel M. K. Miotello A. Patel N. 《Catalysis Letters》2022,152(2):438-451
Catalysis Letters - Mixed transition-metals oxide electrocatalysts have shown huge potential for electrochemical water oxidation due to their earth abundance, low cost and excellent... 相似文献
89.
Devi Neena Patel Sanjay K. S. Kumar Pradeep Singh Archana Thakur Nandita Lata Jeevan Pandey Deepak Thakur Vikram Chand Duni 《Catalysis Letters》2022,152(4):944-953
Catalysis Letters - In this study, Rhodococcus pyridinivorans cells containing hyperactive acyltransferase was immobilized on various macromolecules based-polymeric matrices and used to improve... 相似文献
90.
Silicon - Abundant applications of silica nanoparticles (SiNPs) have motivated many research groups for silica nanoparticles synthesis with tuned properties. Here we show the formation of SiNPs... 相似文献