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41.
The heat conduction characteristic of glass curtain wall was investigated. Based on one dimensional steady heat conduction theory, the numerical calculation model of glass system thermal transmittance was set up by using insulating glass as an example. Based on two dimensional steady heat conduction theory and finite element method, both the thermal transfer matrix and temperature load array of 3 DOFs triangular element were derived. Then the revised formulas about the heat transfer matrix and temperature load array under the boundary conditions of constant heat flux, heat convective, radiation and coupled of them were also derived. Then the numerical calculation models of glass curtain wall frame and linear thermal transmittance were set up. The program TJCW based on the Visual C++ and ObjectARX was developed for calculating the thermal transmittance of glass curtain wall and was validated by contrast with the results calculated by thermal software LBNL. Finally, TJCW program was used to calculate and check the thermal transmittance of glass curtain wall in a practical project. The results indicate that the thermal transmittance of glass curtain wall can be calculated correctly by adopting the presented model, and the program based on this model can be used in energy conservation calculation and analysis in the actual projects. 相似文献
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Mohammed F. Aldawsari Mohammed Muqtader Ahmed Farhat Fatima Md. Khalid Anwer Prakash Katakam Abdullah Khan 《Marine drugs》2021,19(8)
The objective of this work was to develop sustained-release Ca-alginate beads of apigenin using sodium alginate, a natural polysaccharide. Six batches were prepared by applying the ionotropic gelation technique, wherein calcium chloride was used as a crosslinking agent. The beads were evaluated for particle size, drug loading, percentage yield, and in vitro drug release. Particle size was found to decrease, and drug entrapment efficiency was enhanced with an increase in the polymer concentration. The dissolution study showed sustained drug release from the apigenin-loaded alginate beads with an increase in the polymer proportion. Based on the dissolution profiles, BD6 formulation was optimized and characterized for FTIR, DSC, XRD, and SEM, results of which indicated successful development of apigenin-loaded Ca alginate beads. MTT assay demonstrated a potential anticancer effect against the breast cancer MCF-7 cell lines. The antimicrobial activity exhibited effective inhibition in the bacterial and fungal growth rate. The DPPH measurement revealed that the formulation had substantial antioxidant activity, with EC50 value slightly lowered compared to pure apigenin. A stability study demonstrated that the BD6 was stable with similar (f2) drug release profiles in harsh condition. In conclusion, alginate-based beads could be used for sustaining the drug release of poorly water-soluble apigenin while also improving in vitro antitumor, antimicrobial, and antioxidant activity. 相似文献
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Clinical features of canine pulmonary veno‐occlusive disease and pulmonary capillary hemangiomatosis
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探求层压板的玻璃化转变温度(tg)对层压板性能的影响,对研制开发层压板新产品和选择适用层压板制作印刷电路板有重要的理论意义和实际意义。对不同tg的层压板的耐热性、抗弯强度和热膨胀性等8项性能进行了比较。结果表明层压板的tg升高,层压板的机械和电气性能明显提高。 相似文献
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免疫磁珠分离技术在生物检测中的应用日益广泛,能提供高强度大梯度磁场环境的纳米磁珠分离器是免疫磁珠分离技术中的关键技术之一。设计了一种新颖的环形六孔纳米磁珠分离器,通过瓦状钕铁硼磁块的优化布局和斜壁坡莫合金导磁片设计,实现了在同一台纳米磁珠分离器上形成6个强磁场高梯度分离区域(分离孔),分离器最高磁场强度达1.44 T,最高磁场梯度达96.3 T/m(体积865.5 cm3,质量4.8 kg),同一分离器内6个分离孔内磁场分布相同,孔间平均相对偏差在2.0%~3.3%之间。对磁分离孔磁场分布的测试和仿真结果表明:磁珠分离器体积、导磁片材料和导磁片形状等因素对磁珠分离器磁场强度和梯度有不同程度的影响,采用大体积磁块的磁珠分离器比采用小体积磁块的磁珠分离器、采用坡莫合金作为导磁片比采用软铁材料作为导磁片、采用斜壁形状的导磁片比采用直壁形状的导磁片均能实现较大的磁场强度和梯度。该纳米磁珠分离器已成功应用于大肠杆菌和禽流感病毒的免疫磁分离试验研究,并可以根据不同应用需求,组合相关要素以获得理想的免疫磁珠分离器。 相似文献
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采用磁珠富集法筛选三疣梭子蟹(Portunus trituberculatus)的微卫星序列。经Sau3AI酶切后的200~1000bp DNA纯化片段,与两端已知序列的人工接头连接,用含有生物素标记的(CA)12和(GA)12探针杂交,根据磁珠的链酶亲和素与生物素特异结合的特性,捕获含微卫星序列的单链DNA,以此为模板用人工接头序列为引物进行PCR扩增,随后将获得的片段连接到PMD18-T载体上,转化至DH5α感受态细胞中,成功构建了微卫星富集文库。测序其中的60个阳性克隆,得到42条微卫星序列(基因登录号为:HQ283153-HQ283194),除探针使用的CA/GT、GA/CT重复外,还得到GAGT重复序列。42条微卫星序列中,完美型31个(占73.8%),非完美型9个(占21.4%),混合型2个(占4.8%)。完美型的比例显著高于非完美型,这与其他真核生物微卫星序列的特征相一致。39条微卫星序列的重复次数大于10(占92.9%),其中,重复次数在10~19次之间的有27个,20次以上的有12个。筛选出的微卫星位点可为今后三疣梭子蟹遗传多样性评价、种群遗传结构鉴定及资源保护研究提供一套有用的分子标记。 相似文献
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