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1.
Juan Carlos Benítez Carlos A. Giúdice Vicente J. D. Rascio 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(8):387-394
This paper discusses the bioactivity of antifouling paints based on organotin toxicants, such as tributyltin fluoride (TBTF) and triphenyltin fluoride (TPTF). These compounds were used alone or mixed as the main toxicant in formulations. The use of TPTF or mixtures of TPTF and TBTF, with vinyl binders, led to paints with satisfactory bioactivity during a 24 months immersion period. With the same binders, TBTF alone provided only 12 months of antifouling protection. The correlation coefficients calculated from the fouling attachment values and the rosin content in the binder showed that the bioactivity of the tested formulations depended on the solubility of the toxicant in sea water and on the composition and solubility of the binders. 相似文献
2.
Fadila Ayati Majda Aziza Rachida Maachi Abdeltif Amrane 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(1):27-33
BACKGROUND: Three groups of amino acids were previously characterized based on their ability to be assimilated as carbon source by Penicillium camembertii. To describe the diauxic growth recorded on glucose and amino acids from the second group, such as arginine, an unstructured model was previously developed, based on the sequential consumption of both carbon substrates, glucose, followed after its exhaustion, by arginine. The model was modified to describe also the behaviour recorded during growth on other amino acids. RESULTS: The growth model involved the carbon substrate consumption (Verlhust model) and the biomass on carbon substrate yield. Glucose was therefore considered during P. camembertii growth on nitrogen source amino acids (lysine—first group); and amino acid consumption was considered during growth on carbon source amino acids (glutamate—third group), with glucose being dissimilated only for energy supply. The excess nitrogen from amino acids was released as ammonium; the linking of this production to growth was found to increase with the ability of the amino acid to be assimilated as carbon source by P. camembertii. CONCLUSION: The various metabolic behaviours recorded during P. camembertii growth on amino acids, in the presence of a primary carbon source such as glucose, were proved to be satisfactorily described by the model, showing the robustness of the model. Copyright © 2007 Society of Chemical Industry 相似文献
3.
汉江流域水草漂浮物多发,影响水生态环境、发电、航运、供水等,故对碾盘山水电站拦导漂排设计方案进行了比选研究。当前水电站工程漂浮物治理多依靠人力与船只机械清理,存在安全、失控、低效等诸多问题,不利于工程发挥长期稳定效果。根据汉江漂浮物特征及碾盘山枢纽运行特点,经对设计方案结构荷载和安全稳定分析,运用已开发的水力一体拦导漂浮排技术装备和实用成果,在电站引水渠布置水力一体拦导漂排,将漂浮物引导至泄水闸适时开闸排向下游。该方案有利于充分发挥电站发电效益,保障工程安全运行。水力一体治漂适应漂浮物规律,系列技术适应各类工程综合治漂,解决工程治漂短板。 相似文献
4.
Barbora Peltanova Marketa Liskova Jaromir Gumulec Martina Raudenska Hana Holcova Polanska Tomas Vaculovic David Kalfert Marek Grega Jan Plzak Jan Betka Michal Masarik 《International journal of molecular sciences》2021,22(4)
Cancer-associated fibroblasts (CAFs) are one of the most abundant and critical components of the tumor stroma. CAFs can impact many important steps of cancerogenesis and may also influence treatment resistance. Some of these effects need the direct contact of CAFs and cancer cells, while some involve paracrine signals. In this study, we investigated the ability of head and neck squamous cell carcinomas (HNSCC) patient-derived CAFs to promote or inhibit the colony-forming ability of HNSCC cells. The effect of cisplatin on this promoting or inhibiting influence was also studied. The subsequent analysis focused on changes in the expression of genes associated with cancer progression. We found that cisplatin response in model HNSCC cancer cells was modified by coculture with CAFs, was CAF-specific, and different patient-derived CAFs had a different “sensitizing ratio”. Increased expression of VEGFA, PGE2S, COX2, EGFR, and NANOG in cancer cells was characteristic for the increase of resistance. On the other hand, CCL2 expression was associated with sensitizing effect. Significantly higher amounts of cisplatin were found in CAFs derived from patients who subsequently experienced a recurrence. In conclusion, our results showed that CAFs could promote and/or inhibit colony-forming capability and cisplatin resistance in HNSCC cells via paracrine effects and subsequent changes in gene expression of cancer-associated genes in cancer cells. 相似文献
5.
利用ADINA有限元软件对单跨梁板式筏形基础进行了冲切模拟和非线性分析,得出了筏板基础的裂缝、变形及地基反力分布。结果表明:在小荷载情况下,筏板的地基反力分布比较均匀,随着荷载的增加,筏板的地基反力呈非线性分布并且主要集中在肋梁及其周围2.5倍板厚的范围内;板格及肋梁都出现了反向弯曲的现象;冲切验算时考虑了板格冲切破坏模式和节点破坏模式2种情况,并取两者的最不利值作为筏板的冲切承载力。数值模拟结果为筏板结构设计和试验研究提供了理论依据。 相似文献
6.
赵蕴林 《四川轻化工学院学报》2010,(3):369-372
文章结合工程设计经验对自贡地区的高层建筑在选用天然筏板基础的设计过程中,对高层建筑基础设计中涉及到的重要的地基沉降计算、结构设计和地下水等有关问题的处理进行了具体分析,对在一般高层建筑中采用天然筏板基础的实用性和可行性从设计和施工两个方面进行了相关的工程探讨。 相似文献
7.
徐卓根 《吉林建筑工程学院学报》2015,32(2)
深基础是广泛应用于桥梁和高层建筑工程的基础形式.本文选取了两例高层建筑基础案例进行了对比分析,其一为位于纽约市的布鲁克林大厦,采用了配有微型桩基础的筏式基础;另一案例为香港的国际商贸大厦,采用了大型围堰.分析表明微型桩与筏式基础联合使用可有效控制基础沉降,且具一定灵活性与经济性,可以推广使用. 相似文献
8.
邓殷 《重庆电力高等专科学校学报》2014,19(5):30-32
分析民族音乐面临的困境与发展现状,揭示我国民族音乐的独特内涵及深远的意义,从民族音乐的收集与整理、教材的编写与推广、课程与师资队伍建设、教学模式的创新,音乐教育资源的整合、民族音乐文化活动的开展与弘扬等方面,提出推进民族音乐在高校音乐教育中的融入与发展的对策。 相似文献
9.
Humorously describes fictional studies "proving" that motor and language development occur concurrently ("hand in hand") and that this development is independent of culture. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
将群桩筏板基础离散成桩和弹性板,桩筏基础与地基的共同作用转化为桩、弹性板与地基之间的力与位移协调分析。对不同的地基模型求解相应的地基柔度系数,同时将桩作为弹性杆件求解其柔度系数,并将筏板视为地基上的四边自由矩形板,求出其在地基反力、桩顶反力和外荷载以及简支边广义位移共同作用下的位移,最后通过力和位移协调建立桩、筏、地基之间的共同作用方程并求解。算例对比表明半解析半数值方法具有较好的精度,能满足实际工程计算需要。 相似文献