用 X 射线测定球体在高含沙浑水中的沉降特性

本文叙述了应用 X 射线在萤光屏幕上直观地分析球体在高含沙浑水中的沉降特性的方法,研究单个球体在均质宾汉体浑水中不沉降极限粒径以及沉速等问题.这一试验技术较其它方法相比,由于采用屏幕显示,因此具有直观、准确等优点,还可应用电视录相的方法,把投影在 X 光屏幕上的图像拍摄下来,进行复演和定性及定量的分析.通过实验发现,某些宾汉体浑水的屈服应力是随着宾汉体浑水的静止历时增长而加大,它具有触变特性.     

计算多组分精馏理论板数的一个新方法

本文提供了计算多组份精馏理论塔板数的一个新方法,系将多组份精馏视作轻重二关键组元的提纯,经过简化及数学处理计算,得到精馏段及提馏段所需的理论塔板数,其准确度在我们验证的范畴内不低于常用的简捷法而与逐板计算法接近。     

Production and characterization of antibodies cross-reactive with major aflatoxins

Antibodies cross-reactive with 4 major aflatoxins were demonstrated three weeks after immunization of rabbits with an immunogen which was prepared by conjugating aflatoxin B3 to bovine serum albumin. Aflatoxin B3 was first converted to its hemisuccinate before conjugation to the protein. Tritiated aflatoxin B1 (AFB1) was used as the marker ligand both for antibody titer determination as well as for analysis of antibody specificity. Competitive RIA revealed that the antibodies have good cross-reactivity with aflatoxins B1, B2, G1, and G2 when tritiated AFB1 was used as the marker ligand. The concentrations causing 50% inhibition of binding of 3H-AFB1 to the antibodies by unlabeled aflatoxins B1, B2, G1, G2 and B3 were found to be 0.25, 3.34, 0.32, 4.0 and 0.53 ng/assay, respectively. The antibodies could be used for simultaneous analysis of aflatoxins B1 and G1, two of the most important toxic metabolites produced by Aspergillus flavus and A. parasiticus.     

畜禽的微量元素中毒

概述畜禽微量元素中毒的原因、症状、机理、临床诊断和防治后,分别阐述铜、汞、氟三种中毒症。     

产业用纤维材料的耐候性和耐热性研究

本文对我国常用的几种产业用纤维材料的耐候性和热老化性能进行了测试分析。随着室外老化和仪器老化时间的增加,纤维材料强度和断裂伸长率降低;同时,纤维因受气候条件的侵蚀而表面下陷,出现斑点、凹坑和裂纹.仪器老化能较好地模拟室外自然老化试验,且数据稳定,试验周期短。两者的强度保持率随着老化时间均按指数规律 Y=ae~(bx)降低,试验常数 a 和 b 决定于纤维品种,规格和气候老化条件等参数。在经130℃热老化处理后,常用几种产业用纤维的强伸性能均发生不同程度的恶化;但在80℃条件下,性能变化较小。     

氢对ODS铁素体钢辐照性能的影响

采用离子注入和高压电镜原位观察的方法，研究了氢对国产ＯＤＳ铁素体钢辐照性能的影响，结果表明：室温注氢前后ＯＤＳ铁素体钢的微观结构无明显变化；将其加热到５００℃并电子辐照，未观察到辐射空洞，注氢与未注氢ＯＤＳ铁素体钢室温电子辐照的结果表明：氢对点缺陷的迁移和聚集起着十分重要的作用。     

柴油机组模型及模型参数对调速系统性能的影响

本文详细分析了柴油机组模型及模型参数的物理意义．以Ｘ１９５型柴油机具体参数入手深入探讨了柴油机组模型中诸参数对调速系统性能的影响．     

Central electron-enriched NO-FeN4 sites as superior acidic oxygen reduction reaction electrocatalysts for proton exchange membrane fuel cells

Developing nobel-metal-free catalysts, especially for iron-nitrogen on carbon (FeNC) materials, has been an urgent demand for wide applications of proton exchange membrane fuel cells (PEMFCs). However, the inferior oxygen reduction reaction (ORR) activity of traditional iron-nitrogen sites in acidic conditions seriously impedes the further improvement of their performance. Herein, we synthesized FeN₄ with NO (nitric oxide) group axial modification (denoted as NO-FeN₄) on a large scale through a confined small molecule synthesis strategy. Benefitting from the strong electron-withdrawing effect of the NO group, the central electron-rich FeN₄ site exhibits ultrahigh ORR activity with a three times higher mass activity (1.1 A·g?1 at 0.85 V) compared to the traditional FeN₄ sample, as well as full four-electron reaction selectivity. Moreover, the PEMFC assembled with the as-prepared electrocatalyst also exhibits a greatly enhanced peak power density (>725 mW·cm?2). This work provides a new approach to rationally design advanced M-N_x nonnoble electrocatalysts for the ORR.     

灰色理论在均匀设计实验因素分析中的应用

本文探讨了灰色理论应用于均匀设计实验因素分析中的可行性，确定了灰色关联分析应用于均匀设计实验因素分析中的方法，并给出应用举例。     

用电化学法研究咪唑啉类缓蚀剂对碳钢的缓蚀性能

本文用线性极化，Tafel曲线，交流阻抗等电化学方法测定了三种咪唑类缓蚀剂在油田水中对碳钢的缓蚀性．找出缓蚀剂的最佳有效浓度，比较出这几种缓蚀剂之间的缓蚀效率大小，初步分析其缓蚀机理及其缓蚀效率差异的原因