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101.
Aligned multi-walled carbon nanotube forests were grown by chemical vapour deposition on carbon fibers by the use of an amorphous Si interface. The Si layer creates a barrier, hindering the Fe catalyst diffusion into the carbon fibers. This method provides a way to tailor the thermal, electrical and mechanical properties of the fiber-resin interface of a polymer composite.  相似文献   
102.
利用硅烷偶联剂KH-570对表面无机包覆SiO2前、后的六钛酸钾晶须(PTW)进行有机表面改性,比较了硅烷偶联剂改性无机包覆SiO2处理前、后的PTW对卷材涂料隔热性能的影响.采用红外光谱(IR)、热重分析(TG)方法对改性前后的PTW进行了表征.结果表明,SiO2以化学键键合在PTW表面,KH-570在PTW表面形成了有机包覆层.涂膜隔热性能测试结果表明,以9%SiO2包覆处理后再用偶联剂KH-570改性的PTW能明显改善隔热卷材涂料的隔热性能,其热反射率达到75.4%,比不含PTW的漆膜提高了34.4个百分点,比含直接用偶联剂KH-570改性的PTW的漆膜提高了12.8个百分点.  相似文献   
103.
从产品市场需求、价格水平、原料供应、产品生产成本竞争力等方面分析了在湖北荆州地区建设煤制尿素项目的可行性.  相似文献   
104.
Infections by the zoonotic foodborne bacterium Campylobacter jejuni (C. jejuni) are among the most frequent causes of bacterial gastroenteritis worldwide. The aim was to evaluate the relationship between epithelial barrier disruption, mucosal immune activation, and vitamin D (VD) treatment during C. jejuni infection, using intestinal epithelial cells and mouse models focused on the interaction of C. jejuni with the VD signaling pathway and VD treatment to improve C. jejuni-induced barrier dysfunction. Our RNA-Seq data from campylobacteriosis patients demonstrate inhibition of VD receptor (VDR) downstream targets, consistent with suppression of immune function. Barrier-preserving effects of VD addition were identified in C. jejuni-infected epithelial cells and IL-10−/− mice. Furthermore, interference of C. jejuni with the VDR pathway was shown via VDR/retinoid X receptor (RXR) interaction. Paracellular leakiness of infected epithelia correlated with tight junction (TJ) protein redistribution off the TJ domain and apoptosis induction. Supplementation with VD reversed barrier impairment and prevented inhibition of the VDR pathway, as shown by restoration of transepithelial electrical resistance and fluorescein (332 Da) permeability. We conclude that VD treatment restores gut epithelial barrier functionality and decreases bacterial transmigration and might, therefore, be a promising compound for C. jejuni treatment in humans and animals.  相似文献   
105.
利用铜模吸铸法合成Cu—ZrTi—In非晶棒。块体非晶合金Cu50Zr37Ti8In5的△瓦值最大,为66K。从原子尺寸大小和热力学角度分析在铜基非晶合金中添加适量In元素后能够提高其非晶形成能力的原因。在所测的块体非晶合金Cu55.Zr37Ti8Inx(x≤〈5),Cu52Zr37Ti8In3表现出最高的抗压强度(1981MPa)和最佳的塑性,其在压缩断裂前的总塑性变形量约为1.2%。  相似文献   
106.
以2013年在陕北定靖中部地区采集的62组地下水水样的全分析测试结果为数据基础,分别用单指标评价法、内梅罗指数评价法、层级阶梯评价法和模糊综合评价法对地下水进行质量评价,并对评价结果进行综合加权平均,以期得到更加可靠的质量评价结果,旨在为该地区地下水资源的合理开发利用与保护提供依据。评价结果显示,Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ类水所占比例分别为3.23%、11.29%、9.68%、24.19%、51.61%,约75%的地下水不适合直接饮用;该区地下水质量较差。水质整体分布规律为:东北部沙漠—平原地区水质较好,西南部黄土丘陵地区水质差;在局部,油气井开采较密集和芦河周围地区水质较差,说明原生环境和人类活动是造成该区地下水质量差的两个主要原因。  相似文献   
107.
酸化膨润土的分散性研究   总被引:1,自引:0,他引:1  
研究了酸化膨润土在水相中的分散性能。研究表明:在分散机转数3000r/min、时间45min、分散浓度10%、pH5、分散剂用量0.4%的条件下,酸化膨润土分散液表观粘度达到最低,具有良好的分散性。  相似文献   
108.
The emissions from in-use commercial aircraft engines have been analyzed for selected gas-phase species and particulate characteristics using continuous extractive sampling 1-2 min downwind from operational taxi- and runways at Hartsfield-Jackson Atlanta International Airport. Using the aircraft tail numbers, 376 plumes were associated with specific engine models. In general, for takeoff plumes, the measured NOx emission index is lower (approximately 18%) than that predicted by engine certification data corrected for ambient conditions. These results are an in-service observation of the practice of "reduced thrust takeoff". The CO emission index observed in ground idle plumes was greater (up to 100%) than predicted by engine certification data for the 7% thrust condition. Significant differences are observed in the emissions of black carbon and particle number among different engine models/technologies. The presence of a mode at approximately 65 nm (mobility diameter) associated with takeoff plumes and a smaller mode at approximately 25 nm associated with idle plumes has been observed. An anticorrelation between particle mass loading and particle number concentration is observed.  相似文献   
109.
在水雨情信息及其采集技术现状的基础上,结合GSM网络短消息业务的信息传输原理,应用80C196单片机开发了利用GSM网络短消息业务传输技术的水雨情远程信息采集系统。文中介绍了该系统的总体方案设计、遥测站和中心站的硬件/软件设计。  相似文献   
110.
Two adjacent buildings near the epicenter of the January 17th Northridge earthquake, one with weld fractures and one without weld fractures, are considered in this research. Both buildings are six stories in height, and their primary lateral force resisting system comprises special moment resisting frames above grade. The buildings considered are referred to herein as the East Building and the West Building. Two basic types of computer studies were performed. One was an elastic 3-D analysis using SAP90, and the other an inelastic 2-D analysis using DRAIN-2DX. Three different models were, created for the elastic analysis. Two for the East Building, designated the ‘benchmark model’, and the ‘probable model’, and one for the West Building, designated the ‘West Building model’. Two different models were created for the inelastic analysis only for the East Building, also called the benchmark model and the probable model. The East Building was unoccupied at the time of the earthquake, hence two models were created for this building. The benchmark model is representative of the design state of the building, while the probable model is representative of the state of the building at the time of the earthquake. The West Building, which was fully occupied at the time of the earthquake, was modeled similarly to the benchmark. Elastic and inelastic studies were performed on these models to determine if a correlation exists between analysis and observed behavior. The findings from the analysis showed no damage to the West Building with possible damage to the East Building. This result is corroborated by the damage survey.  相似文献   
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