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991.
本文依据热阻网络法,经过迭代计算,对某一太阳能吸附式空气取水器热损所受环境条件影响进行了稳态条件下的数值分析。 相似文献
992.
993.
Linlin Zhou Laipan Zhu Tao Yang Xinmei Hou Zhengtao Du Sheng Cao Hailong Wang Kuo-Chih Chou Zhong Lin Wang 《纳微快报(英文)》2022,(2):151-160
Ultra-stable piezoelectric nanogenerator(PENG)driven by environmental actuation sources with all-weather service capability is highly desirable.Here,the PENG based on N doped 4H-SiC nanohole arrays(NHAs)is proposed to harvest ambient energy under low/high temperature and relative humidity(RH)conditions.Finite element method simulation of N doped 4H-SiC NHAs in compression mode is developed to evaluate the relationship between nanohole diameter and piezoelectric performance.The density of short circuit current of the assembled PENG reaches 313 nA cm-2,which is 1.57 times the output of PENG based on N doped 4H-SiC nanowire arrays.The enhancement can be attributed to the existence of nanohole sidewalls in NHAs.All-weather service capability of the PENG is verified after being treated at-80/80℃and 0%/100%RH for 50 days.The PENG is promising to be widely used in practice worldwide to harvest biomechanical energy and mechanical energy. 相似文献
994.
在煤质的工业分析中,由各种公式换算出的不同煤种的Q~f_(DW)值,实用时尚须按Q~y_(DW)=Q~f_(DW)×(100-W~y)/(100-W~f)-6W~y+6W~f×(100-W~y)/(100-W~f)式换算成应用煤的低位发热量。使用这个公式不仅繁琐费时,且易出错,现行的简算方法如下:Q~y_(DW)=Q~f_(DW)-54H~y-6W~y或Q~y_(DW)=Q~y_(DW)-K_3-K_4其中K_3=54H~y K_4=6W~y(K_3、K_4可由专用表格查算),此式虽较简便,但式中的含氢量H~y值必须通过测定煤样中的碳氢含量并加以换算才能得到,这对于因各种原因不能进行煤的实测发热量及其元素分析的动力用煤企业来讲,此式没有实际意义。作者经过大量统计运算,发现了组成煤本体各种参数在不同条件下对煤质发热量不同程 相似文献
995.
从热力学角度对涂料液体在塑料底材的附着润湿、浸透润湿、铺展润湿行为进行了分析,定性地研究了塑料表面Gibbs能与粗糙因子、涂料液体的表面Gibbs能对塑料-涂料液体界面润湿行为的影响,并用实验进行了验证。 相似文献
996.
基于对协同环境下特征操作的分析,通过动态调整特征操作造型指令并定义一种基于非置锁机制的设计流程,以解决多客户协同设计中的冲突问题,克服常规令牌传递策略缺乏灵活性的弊端,实现了一个基于文中算法的原型系统,设计实例验证了该系统的灵活性和高效性。 相似文献
997.
放电等离子烧结纳米复合Ti(C,N)基金属陶瓷 总被引:1,自引:0,他引:1
采用放电等离子技术(SPS)烧结制备出纳米复合Ti(C,N)基金属陶瓷材料。用光学显微镜、扫描电镜和能谱仪等对烧结体的孔隙率、微观组织和断口形貌等进行了观察,并对不同条件下材料的力学性能进行了对比分析。结果表明:直接升温到1250℃保温8min可获得较好的力学性能;在显微结构中,除了黑芯/白环的结构外,还存在着白芯/黑环结构;孔洞和大颗粒硬质相为主要的断裂源,断裂方式以沿晶断裂为主,同时存在着解理断裂和穿晶断裂。 相似文献
998.
Ming W. Chou Wen Chen Jasyl Nichols Marina Mikhailova Ronald W. Hart 《Polycyclic Aromatic Compounds》2013,33(1-4):211-218
Dietary restriction (DR) alters hepatic drug metabolizing enzyme activities that affect the metabolic activation of xenobiotics. Previously, we have studied the effect of DR on the formation of benzo[a]pyrene (BaP)-DNA adducts in male Fischer 344 rats. In this study, the effects of DR on the formation of specific BaP-DNA adducts in mouse livers were investigated. In addition, 2-acetylaminofluorene (2-AAF) modified DNA adducts in livers of mice and rats were also examined. DR reduced the body and liver weights of male B6C3F1 mice. Both the total [3H]BaP-DNA binding and the specific BaP-DNA adduct, N2-dG-BaP, detected by 32P-postlabeling technique, were found to be greater in DR mice than in animals fed al libitum (AL). The formation of the 2-AAF-DNA adduct, AF-C8-dG, was not affected by DR. Similar results were obtained from the in vitro DNA adduct formation of these two carcinogens mediated by rat and mouse liver microsomes. The effect of DR on the formation of BaP- and 2-AAF-modified DNA adducts is discussed. 相似文献
999.
1000.
On many hillsides of Taiwan there is a unique pattern of weed exclusion byPhyllostachys edulis (bamboo) andCryptomeria japonica (conifer) in which the density, diversity, and dominance of understory species are very different. Although the physical conditions of light, soil moisture, and soil nutrients strongly favor the growth of understory in a bamboo community, the biomass of its undergrowth is significantly low, indicating that physical competition among the understory species in the bamboo and conifer communities does not cause the observed differences. However, the biochemical inhibition revealed by these two plants appeared to be an important factor. The growth ofPellionia scabra seedlings, transplanted from the study site into greenhouse pots, was evidently suppressed by the aqueous leachate of bamboo leaves but was stimulated by that of conifer leaves. The radicle growth of lettuce, rye grass, and rice plants was also clearly inhibited by the leachate and aqueous extracts of bamboo leaves but not by those of conifer leaves. Six phytotoxins,o-hydroxyphenylacetic,p-hydroxybenzoic,p-coumaric, vanillic, ferulic, and syringic acids were found in the aqueous leachate and extracts of leaves and alcoholic soil extracts ofP. edulis, while the first three compounds were absent in the extracts ofC. japonica. The phytotoxicities of extracts were correlated with the phytotoxins present in both leaves and soils. The understory species might be variously tolerant to the allelopathic compounds produced by the two plants, resulting in a differential selection of species underneath. Therefore, comparative allelopathic effects ofPhyllostachys edulis andCryptomeria japonica may play significant roles in regulating the populations of the understories.Paper No. 253 of the Scientific Journal Series of the Institute of Botany, Academia Sinica, Taipei, Taiwan. This study was supported by the National Science Council of the Republic of China. 相似文献