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11.
The influence of transplantable tumour on migration, proliferation and differentiation of haemopoietic stem cells was studied. It is shown that in the initial period of tumour development the migration and proliferation of stem cells intensify. In the final stage of the tumour growth the quantity of haemopoietic stem cells decreases considerably in the bone marrow, spleen, and peripheral blood. It is established that during the tumour growth the differentiation of stem cells from the spleen changed towards erythropoiesis. 相似文献
12.
Refractories and Industrial Ceramics - Slag-resistant highly refractory alumina-periclase-carbon ceramic materials are synthesized on the basis of electrocorundum (Kazogneupor), Zinel’bulaksk... 相似文献
13.
Abdul‐Rashid Abdul‐Aziz Mastura Jaafar Abdul Aziz Hussin 《Construction Management & Economics》2013,31(10):1009-1019
Despite privatization, many government‐linked companies (GLCs) still continue to operate in Malaysia. Many have objectives that include the redressing of ethnic economic imbalance. Government‐linked construction companies (GLCCs) were created within these larger public groups. A study was conducted to explore whether the GLCCs are still valid in Malaysia's present construction industry scenario, and if not, what actions should be taken in respect of them. Four aspects (i.e. social obligation, competitiveness, efficiency and income generation) were looked into. To answer the research questions, the viewpoints of ‘A’ Class bumiputera contractors were solicited which were then investigated on four GLCCs, three belonging to state economic development corporations (SEDCs) and one to a land development agency (LDA). The exploratory study found that three case study GLCCs have limited public value. This paper concludes by recommending changes that should be made to them. There is much that policy makers in developing countries with GLCCs can learn from the Malaysian experience. At the very least, it underscores the need to assess their raison d'être periodically. This study also hopes to encourage other scholars to look into a much under‐researched area—that of a particular set of actors commonly created to promote local construction industry development. 相似文献
14.
目的 药品包装材料与药物相容性实验是评价药品包装材料安全性能与药品质量的重要研究项目,中性硼硅玻璃具有膨胀系数小、耐极冷极热性强、不易炸裂、化学稳定性好等特点,已成为注射剂包装的首选材质.探索中性硼硅玻璃与药物相容性的研究进展与发展趋势,为中性硼硅玻璃用于药品包装材料提供参考.方法 分别从玻璃成分中金属离子向药液中的迁移量、有害物质的浸出量、不同温度与酸碱条件下玻璃的脱片、玻璃对药物的吸附以及药物对玻璃表面的侵蚀程度等方面综述中性硼硅玻璃与药物相容性的研究进展,考察中性硼硅玻璃对于药品质量的影响.结论 中性硼硅玻璃与药物的相容性评价方法逐渐完善,为中性硼硅玻璃作为药用包装材料的研究提供参考. 相似文献
15.
Trang An Duong Farrukh Erkinov Mastura Aripova Chang Won Ahn Byeong Woo Kim Hyoung‒Su Han Jae‒Shin Lee 《Ceramics International》2021,47(4):4925-4932
This study investigated the phase transition behavior and electrical properties of (K0.5Na0.5)(Nb1-xZrx)O3 (KNN?100xZ) and (K0.5Na0.5)NbO3–yBaZrO3 (KNN–100yBZ) lead–free piezoelectric ceramics. The phase transitions in crystal structures were compared in KNN ceramics between single Zr4+ doping and Ba2+Zr4+ co?doping. Piezoelectric properties such as the piezoelectric constant (d33) and electromechanical coupling factor (kp) are optimized for KNN?6BZ ceramics and were clarified via the polymorphic phase transition from the orthorhombic to pseudocubic phase. The fitted degree of diffuseness (γ) for a phase transition from the modified Curie–Weiss law indicated that KNN ceramics as ferroelectrics are gradually transformed through BaZrO3 modification. Accordingly, the enhanced strain properties at y = 0.08 consist of coexisting ferroelectric domains and polar nanoregions that are supported by ferroelectric–to–relaxor crossover in KNN?100BZ ceramics. 相似文献
16.
A GIS-ANN-Based Approach for Enhancing the Effect of Slope in the Modified Green-Ampt Model 总被引:1,自引:0,他引:1
Mohammad Dorofki Ahmed H. Elshafie Othman Jaafar Othman A. Karim Sharifah Mastura Syed Abdullah 《Water Resources Management》2014,28(2):391-406
Most infiltration models survey infiltration in large scale regions using an assumption that the slope of the ground is equal to zero. The Modified Green and Ampt model is one of a few infiltration models that considers slope as an input parameter in its formulation. Here, using artificial neural networks in a raster-based design, basic research is presented regarding the effect of surface slope on infiltration. For the investigation, three catchments with different areas and slopes were selected as case studies, based on existing runoff stations in the upstream region of the Johor River Basin in southern Malaysia. In this research, the efficiency of six different functions was studied in order to determine the best performer for slope in the Modified Green and Ampt model. We also sought to find the most suitable ANN transfer function for infiltration calculations. By calculating runoff for each pixel, accumulation maps were used for corroborating the suitability of the obtained results. The results indicated that the Log-sigmoid was the most appropriate transfer function. We also determined that using the exponential form for the slope in the Modified Green and Ampt model formulation was more accurate, as compared to the original linear shape. 相似文献
17.
Ultrafiltration (UF) is an alternative option that can be used to clarify glycerin-rich solutions in the oleochemical industry. However, the UF membranes used in the process were observed to have been seriously fouled in our preliminary study. Thus, the ultrafiltration of a glycerol-water-fatty acid mixture was carried out to investigate the membrane binding properties of the components and their contributions to membrane fouling. Palmitic, stearic, and oleic acid were used as fouling substances in the glycerol-water mixture. The flux decline experiments were carried out using polyvinylidenefluoride (PVDF) as well as polyethersulphone (PES) membranes with a MWCO of 30 and 25 kDa, respectively at specific conditions (T = 40 °C; ΔP = 2 bar). It was found that the PES membrane exhibited severe fouling for all types of fatty acids in solution with glycerol-water. As the pH decreased to acidic conditions, the PES membrane tended to exhibit more severe fouling than the PVDF membrane. 相似文献