漏电保护开关在民用建筑中的应用

防止触电事故和电气火灾的发生，都要考虑设漏电保护装置，这是电击防护的第三道防线。在民用建筑中安装漏电保护开关是安全用电的有效措施。文中详细介绍了装漏电保护开关后可进一步提高安全性的实例。对民用建筑低压配电设计具有一定的参考作用。     

齐格勒型催化剂失产低分子聚烯烃技术进展

介绍了国外低分子聚烯烃的生产技术，论述了用齐格勒型催化剂时，工艺条件、技术手段的实施。     

钢铁厂总图运输设计与节约用地

我国是一个幅员辽阔人口众多的国家，国土面积960万km^2，山地面积大，山地、丘陵、崎岖的高原占67％，土地的承载性、肥沃度低。土地资源是国民经济与社会发展最重要的物质基础，是人们赖以生存和发展的生产资料。近些年由丁土地资源的粗放型管理以及荒漠面积的扩大（2005年荒漠面积达264万km^2），致使人多地少的矛盾日益突出。据预测到2040年，我国耕地将突破承载极限，土地己成为制约经济和社会发展的重要因素之一，节约用地迫在眉睫。     

Neuromagnetic localization using magnetic resonance images

Ionic flow associated with neural activation of the brain produces a magnetic field, called the neuromagnetic field, that can be measured outside the head using a highly sensitive superconducting quantum interference device (SQUID)-based neuromagnetometer. Under certain conditions, the sources producing the neuromagnetic field can be localized from a sampling of the neuromagnetic field. Neuromagnetic measurements alone, however, do not contain sufficient information to visualize brain structure. Thus, it is necessary to combine neuromagnetic localization with an anatomical imaging technique such as magnetic resonance imaging (MRI) to visualize both function and anatomy in vivo. Using experimentally measured human neuromagnetic fields and magnetic resonance images, the authors have developed a technique to register accurately these two modalities and have applied the registration procedure to portray the spatiotemporal distribution of neural activity evoked by auditory stimulation.     

Characteristic mode theory of coupled waveguide arrays with periodically varying properties

A method is presented for determining the eigenvalues and eigenvectors (characteristic mode shapes) for coupled waveguide arrays in which the interguide coupling is uniform but where the dephasing varies periodically from guide to guide. It is demonstrated that if the dephasing alternates from guide to guide, a quadratic equation must be solved for the eigenvalues, whatever the number of guides. For dephasing functions of larger period, the eigenvalue equation is of correspondingly higher order. The effect of such functions is to insert additional band gaps into the eigenvalue distribution and to couple together spatial harmonics. Numerical examples illustrating the method are presented where relevant.     

聚丙烯改性技术进展

介绍了近年来聚丙烯改性技术研究方面的进展．研究内容包括用结晶成核剂对聚丙烯的晶型进行设计，用橡胶、矿物填料等对聚丙烯进行改性．     

Incorporation and distribution of saturated and unsaturated fatty acids into nuclear lipids of hepatic cells

Liver nuclear incorporation of stearic (18∶0), linoleic (18∶2n−6), and arachidonic (20∶4n−6) acids was studied by incubation in vitro of the [1-¹⁴C] fatty acids with nuclei, with or without the cytosol fraction at different times. The [1-¹⁴C] fatty acids were incorporated into the nuclei as free fatty acids in the following order: 18∶0>20∶4n−6≫18∶2n−6, and esterified into nuclear lipids by an acyl-CoA pathway. All [1-¹⁴C] fatty acids were esterified mainly to phospholipids and triacylglycerols and in a minor proportion to diacylglycerols. Only [1-¹⁴C] 18∶2n−6-CoA was incorporated into cholesterol esters. The incorporation was not modified by cytosol addition. The incorporation of 20∶4n−6 into nuclear phosphatidylcholine (PC) pools was also studied by incubation of liver nuclei in vitro with [1-¹⁴C]20∶4n−6-CoA, and nuclear labeled PC molecular species were determined. From the 15 PC nuclear molecular species determined, five were labeled with [1-¹⁴C]20∶4n−6-CoA: 18∶0–20∶4, 16∶0–20∶4, 18∶1–20∶4, 18∶2–20∶4, and 20∶4–20∶4. The highest specific radioactivity was found in 20∶4–20∶4 PC, which is a minor species. In conclusion, liver cell nuclei possess the necessary enzymes to incorporate exogenous saturated and unsaturated fatty acids into lipids by an acyl-CoA pathway, showing specificity for each fatty acid. Liver cell nuclei also utilize exogenous 20∶4n−6-CoA to synthesize the major molecular species of PC with 20∶4n−6 at the sn-2 position. However, the most actively synthesized is 20∶4–20∶4 PC, which is a quantitatively minor component. The labeling pattern of 20∶4–20∶4 PC would indicate that this molecular species is synthesized mainly by the de novo pathway.     

板坯连铸结晶器Co基合金涂层抗冷热疲劳性能研究

采用HVOF对板坯连铸结晶器窄边CrZrCu板喷涂C0基合金涂层，与电镀Co—Ni镀层进行对比分析。结果表明：450℃下进行冷热疲劳试验，Co基合金涂层经过113次后，涂层还保持完好无损，未出现任何缺陷，而电镀镀层只能承受37．8次；800℃时，Co基合金涂层经过29．4次冷热疲劳后，有3l％的涂层剥落，而电镀层只能承受21．4次。这说明HVOF涂层具有非常高的抗冷热疲劳性能。     

Effect of a physical phase plate on contrast transfer in an aberration-corrected transmission electron microscope

In this theoretical study we analyze contrast transfer of weak-phase objects in a transmission electron microscope, which is equipped with an aberration corrector (C(s)-corrector) in the imaging lens system and a physical phase plate in the back focal plane of the objective lens. For a phase shift of pi/2 between scattered and unscattered electrons induced by a physical phase plate, the sine-type phase contrast transfer function is converted into a cosine-type function. Optimal imaging conditions could theoretically be achieved if the phase shifts caused by the objective lens defocus and lens aberrations would be equal to zero. In reality this situation is difficult to realize because of residual aberrations and varying, non-zero local defocus values, which in general result from an uneven sample surface topography. We explore the conditions--i.e. range of C(s)-values and defocus--for most favourable contrast transfer as a function of the information limit, which is only limited by the effect of partial coherence of the electron wave in C(s)-corrected transmission electron microscopes. Under high-resolution operation conditions we find that a physical phase plate improves strongly low- and medium-resolution object contrast, while improving tolerance to defocus and C(s)-variations, compared to a microscope without a phase plate.