摘要：针对弹齿链耙式残膜回收机存在脱膜不彻底、可靠性低等问题,设计一种固定刮板式脱膜装置,并对其关键部件进行设计与分析。为验证脱膜装置作业性能,以机具行驶速度(A)、弹齿长度(B)、弹齿与脱膜板夹角(C)为试验因素,以脱膜率为试验指标开展L_9(3~4)正交试验。结果表明,弹齿链耙式残膜回收机的脱膜率为92.5%~95.7%;极差分析表明,各因素影响大小为A>C>B,脱膜率最优试验条件组合为A_(2)B_(1)C_(2),即机具行驶速度为8 km/h、弹齿长度为160 cm、弹齿与脱膜板夹角为50°。对最优组合(A_(2)B_(1)C_(2))做验证试验(5次),平均脱膜率为95.16%,满足弹齿链耙式残膜回收机作业要求。

摘要：受天然酶启发,协同作用被广泛应用于小分子的识别及其催化转化,但在聚合物合成领域的研究仍然有限.本文报道了一种柔性桥联双核卟啉铝催化剂(FTBC),成功实现了CO_(2)与环氧丙烷(PO)的高效交替共聚.该策略的关键在于通过调控柔性链的长度使得活性位点相互靠近,从而促进分子内协同作用.受益于活性位点的协同效应,以―CH_(2)―为柔性链的C_(1)-Al_(2)表现出优异的催化活性(380 h^(−1))及较高的聚合物选择性(96%),优于相同条件下的单分子卟啉铝(活性为300 h^(−1),聚合物选择性为78%).即使在低催化剂浓度下,C_(1)-Al_(2)也能保持较好催化活性(250 h^(−1)).动力学实验表明C_(1)-Al_(2)反应级数为一级,证实催化剂的分子内协同催化主导共聚过程.本文报道了一种柔性桥联双核催化剂的构筑策略,为模块化设计高性能催化剂提供了新方向.

摘要：High transparency and toughness are prerequisites for sustainable polymers if they are to find wide application as alternatives to petroleum-based ***,the utility of sustainable polymers such as commercially available polylactide(PLA)is limited by their inherent brittleness and high ***,toughening PLA-based materials via cost-effective blending strategies without sacrificing transparency remains a ***,we report a novel strategy involving active refractive index matching for creation of highly transparent and tough PLA ***,we engineered the refractive index of a promising renewable poly(epichlorohydrin-co-ethylene oxide)elastomer by introducing polar ionic moieties via a simple chemical method,and we blended the resulting ionomers with *** best blend showed an impact strength of>80 kJ/m2,an elongation at break of 400%,and high transparency(90%).These characteristics are of great importance for potential applications such as *** strategy offers a versatile new way to prepare high-performance sustainable polymer materials with excellent transparency.

摘要：目的:设计了一款抗酸染色玻片架装置,以在操作人员进行涂片染色过程中节省时间、减轻劳动强度。方法:此玻片架的染色框架、框架凸起点、座架、抬起架、支撑架均为不锈钢抗酸材料,防止短时间出现腐蚀。玻片架的手柄材料为耐热团状模塑料,保证在200℃以下不会过热变质。结果:试用期间该抗酸染色玻片架没有出现酸腐蚀现象,操作人员极易上手,不容易出现涂片掉落现象。结论:新型抗酸染色玻片架结构合理、实用经济,操作简单,涂片染色质量稳定有保证,冲洗染液的时间减少,有效提高工作效率,且可降低水流冲刷溅起的染液气溶胶,对工作环境和工作人员都起到了保护作用。

摘要：A Laval-type supersonic gas atomizer was designed for low-pressure gas atomization of molten metals. The principal design ob-jectives were to produce small-particle uniform powders at lower operating pressures by improving the gas inlet and outlet structures and op-timizing structural parameters. A computational fluid flow model was developed to study the flow field characteristics of the designed atom-izer. simulation results show that the maximum gas velocity in the atomization zone can reach 440 m＆#183;s-1;this value is independent of the atomization gas pressure P0 when P0〉0.7 MPa. When P0=1.1 MPa, the aspiration pressure at the tip of the delivery tube reaches a mini-mum, indicating that the atomizer can attain the best atomization efficiency at a relatively low atomization pressure. In addition, atomization experiments with pure tin at P0=1.0 MPa and with 7055Al alloy at P0=0.8 and 0.4 MPa were conducted to evaluate the atomization capa-bility of the designed atomizer. Nearly spherical powders were obtained with the mass median diameters of 28.6, 43.4, and 63.5μm, respec-tively. Compared with commonly used atomizers, the designed Laval-type atomizer has a better low-pressure gas atomization capability.

摘要：Hydrogen,regarded as a promising energy carrier to alleviate the current energy crisis,can be generated from hydrogen evolution reaction(HER),whereas its efficiency is impeded by the activity of ***,effective strategies,such as strain and interfacial engineering,are imposed to tune the catalysis performance of novel two-dimensional(2D)phosphorus carbide(PC)layers using first-principle *** findings show that P site in pristine monolayer PC(ML-PC)exhibits higher HER performance than C ***,constructing bilayer PC sheet(BL-PC)can change the coordinate configuration of P atom to form 3-coordination-P atom(3-co-P)and 4-coordination-P atom(4-co-P),and the original activity of 3-co-P site is higher than the 4-co-P *** an external compressive strain is applied,the activity of the 4-co-P site is enhanced whereas the external strain can barely affect that of 3-co-P ***,the graphene substrate enhances the overall activity of the BL-PC because the graphene substrate optimizes the?GH*value of 4-co-P site,although it can barely affect the HER activity of 3-co-P site and *** desirable properties render 2 D PC-based material promising candidates for HER catalysts and shed light on the wide utilization in electrocatalysis.

摘要：In consideration of the anti-HIV activities of delavirdine, resveratrol and Pidotimod, a novel kind of anti-AIDs drug（compounds 5 and 7） was synthesized. Compound 5 was synthesized by linking the delavirdine derivative to pidotimod, compound 7 was synthesized via linking the delavirdine derivative to resveratrol with terephthalic acid as the conjugated compound by two different routes. The structures were confirmed by means of IH NMR, 13C NMR, IR, MS and elemental analysis. The results for HIV-1 reverse transcriptase assay, quantitative titration of HIV-1 by using MAGI assay and pharmacokinetics assay show that a novel kind of anti-AIDs drug has been synthesized.

摘要：运用录像分析、数理统计、分析归纳等研究方法,针对2015年全国艺术体操个人冠军赛和2015年艺术体操欧锦赛个人单项前3名优秀运动员四项器械共计24套成套动作进行深层梳理,依据2013-2016版国际艺术体操评分规则个人项目评分结构的特征,对中外艺术体操个人运动员难度体系身体与器械的结合进行剖析,从世界优秀运动员的技术特点出发,找出我国个人项目在世界大赛上无法取得优异成绩的根源所在。结果表明:新周期评分结构的特征重推身体与器械并重的主体地位;身体难度的完成质量不容乐观,舞步组合器械技术运用的欠缺,每项器械独有的惊险性动作缺少高超、精准的技术做支撑,器械熟练性动作缺少创意是我国运动员与世界优秀选手身体与器械结合存在显著差距的根源所在;完美、巧妙、惊险、创意的"经典"结合共同提高成套动作的技术、艺术、观赏、创新之美,是我国艺术体操个人运动员身体与器械结合的发展途径。

摘要：Moment in Peking written by Chinese American writer Lin yutang,follows the life of an extended upper-class Beijing family from the time of the Boxer uprising in 1900 to the beginning of the Second sino-Japanese War in *** is both a depiction of the daily life of a Chinese family,and a chronicle of the political and social changes sweeping China during that *** novel takes Taoism as the philosophical backdrop,and the concept of“Life passes like a dream”as the theme,revealing the struggles and vicissitudes of Yao Mulan and her father Yao *** is a unique way for Lin yutang to interpret the Taoism and the Taoist way to follow the nature.

摘要：In this paper, a multi-band metasurface（MS） antenna array with low radar cross section（RCS） performance is proposed and measured. Firstly, a 44 antenna array is composed of four 22 Jerusalem cross structure antenna arrays working at different frequency bands, which is aimed at enhancing the bandwidth effectively. Then, each antenna can be seen as a unit of MS in spite of adding the feeding structure. Based on phase cancellation principle, the MS is arranged into a chessboard configuration in order to realize wideband RCS reduction. Thus, excellent radiation and scattering characteristics are obtained simultaneously. simulated and measured results indicate that this work provides a novel method to achieve bandwidth expansion as well as wideband RCS reduction of the antenna array.