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自适应天线在军用和民用系统中的应用

系统工程与电子技术 1982年第11期 25-31页

作者： P.m.Grant ,C.f.N.Cowan ,宛琰

一、前言人们正在详细研究自适应天线在雷达、通讯和导航设备中的应用。通过把波束方向图的零位指向任何干扰源,这种天线就能实时地自动响应未知的敌情。由于天线阵权系数对频率敏感,所以自适应天线

关键词：自适应天线天线阵相控阵自适应阵列声纳基阵旁瓣对消器干扰发射机电子干扰设备干扰机

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一种改善中速柴油机性能的电控高压喷油系统

车用发动机 1981年第6期 51-62页

作者： C.m.D.LITTLE,P.f.SCOTT,陈永锴英国格洛斯特.露卡斯布鲁士有限公司英国格洛斯特.露卡斯布鲁士有限公司总工程师工学士总工程师研究总工程师

用户将越来越偏重于根据整个使用期的费用来挑选发动机,而上述费用中的大部分是运行费。今后,要求发动机必须能够燃用多种规格的燃料。据燃烧理论指出,高喷油压力与容易改变喷油定时的结合,可以改善效率。而在很高的油管压力下工作时,... 详细信息

用户将越来越偏重于根据整个使用期的费用来挑选发动机,而上述费用中的大部分是运行费。今后,要求发动机必须能够燃用多种规格的燃料。据燃烧理论指出,高喷油压力与容易改变喷油定时的结合,可以改善效率。而在很高的油管压力下工作时,传统的喷油装置有一些局限性。下面介绍一种新的系统。它保留了用凸轮和滚轮使喷油泵工作的技术,又采用一个电磁控制阀来代替油孔及螺旋槽结构。控制阀的工作程序由电子控制,可以迅速调节转速和控制喷油定时,现已进行的发动机试验证明,大大地提高喷油压力可明显地改善燃油经济性。在发动机其它工况下进行的计算机模拟予测性能表明有类似的改进潜力。在喷油图形状对发动机部分负荷运转的影响方面,理论上也表明有获得改善的可能性。该系统提供的高喷油压力和喷油定时控制的特点给发动机制造厂开辟了设计的新领域。

关键词：发动机试验螺旋槽发动机制造厂引擎试验喷油泵喷油定时气缸压力燃油量喷油装置进气温度电磁线圈喷油系统电子控制

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合成拟除虫菊酯——一类新杀虫剂

农药工业译丛 1980年第6期 24-29页

作者： m.Elliott N.f.Janes 陈光沛程国侯英国Rothamsted实验站杀虫剂和杀菌剂部

拟除虫菊酯的发展情况对于合成拟除虫菊酯化学结构与活性关系的了解的逐步进展以及相应的商业开发,可在(表1)的化合物顺序中反映出来。尽管有些化合物对某种昆虫在生命史某一环节上特别有效,然而经验表明,针对表中所选的两种昆虫的活性... 详细信息

拟除虫菊酯的发展情况对于合成拟除虫菊酯化学结构与活性关系的了解的逐步进展以及相应的商业开发,可在(表1)的化合物顺序中反映出来。尽管有些化合物对某种昆虫在生命史某一环节上特别有效,然而经验表明,针对表中所选的两种昆虫的活性水平能够恰当地为这些化合物提供在实际价值上有用的一般说明。 Staudinger和Ruzicka合成了一些拟除虫菊酯化合物并试验其杀虫活性,研究了结构-活性关系,从而奠定了产生活性必须具备的现代概念。然而,最初商品化的重要进展是由

关键词：菊酸顺式氰基基节甲基苯氧基环丙烷氰根链烷基芳氧基环烷烃除虫菊宿根花卉氯氰菊醋

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地幔交代作用

地球与环境 1987年第5期 27-37+6页

作者： m.f.Roden V.R.murthy 覃振蔚

“地幔交代作用”的思想是由Bailey(1970,1972)明确提出的,用以解释与大陆内上拱及断裂区域有关的高碱性岩浆作用。从那以后,大量研究表明地幔岩石的交代变化是一种常见的现象,它可能对决定来自地幔的岩浆的化学及同位素特征起关键作用... 详细信息

“地幔交代作用”的思想是由Bailey(1970,1972)明确提出的,用以解释与大陆内上拱及断裂区域有关的高碱性岩浆作用。从那以后,大量研究表明地幔岩石的交代变化是一种常见的现象,它可能对决定来自地幔的岩浆的化学及同位素特征起关键作用。本文拟综述这一概念的现状并总结地幔中交代作用的性质

关键词：橄榄岩包体富集 REE 金云母相容元素交代作用变质作用碱性玄武岩角闪石链状硅酸盐矿物矿物相

Electron Raman scattering in semiconductor quantum well wire of cylindrical ring geometry

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Chinese Physics B 2015年第11期24卷 442-447页

作者： Re.Betancourt-Riera Ri.Betancourt-Riera J.m.Nieto Jalil R.Riera Instituto Tecnol ógico de Hermosillo.Avenida Tecnol ógico S/N Col.Sahuaro Departamento de Investigaci ón en física Universidad de Sonora Tecnol ógico de monterrey-Campus Sonora Norte.Bulevar Enrique mazón López No.965

We study the electron states and the differential cross section for an electron Raman scattering process in a semi- conductor quantum well wire of cylindrical ring geometry. The electron Raman scattering developed here can be used to provide direct information about the electron band structures of these confinement systems. We assume that the system grows in a GaAs/Al0.35Ga0.65As matrix. The system is modeled by considering T = 0 K and also a single parabolic con- duction band, which is split into a sub-band system due to the confinement. The emission spectra are discussed for different scattering configurations, and the selection rules for the processes are also studied. Singularities in the spectra are found and interpreted.

关键词： electron states Raman scattering selection rules quantum well wires

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Breast Cancer: Epidemiological, Clinical, and Therapeutic Aspects in Pointe Noire (Congo Brazzaville)

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Open Journal of Pathology 2019年第4期9卷 76-85页

作者： C. f. S. Ngatali A. f. Bolenga Liboko E. Ndounga Y. mabila D. moukassa J. B. Nkoua-mbon P. E. G. Sounga Bandzouzi L. m. A. Boumba Department of Oncology and Internal medicine Loandjili General Hospital Pointe Noire Congo medical Oncology Department CHU-Brazzaville Brazzaville Congo Hospital General Edith Lucie Bongo Oyo Congo Departement of Neurology Loandjili General Hospital Pointe Noire Congo Laboratoire d’Anatomie Pathologie Loandjili General Hospital Pointe Noire Congo

Introduction: Breast cancer is the leading cancer and the leading cause of cancer death in women worldwide. The objective of our study was to describe the epidemiological, clinical and therapeutic aspects of breast cancer at the General Hospital of Loandjili in Pointe Noire. Patients and methods: This was a descriptive and cross-sectional study that took place in the Cancer Department of the General Hospital of Loandjili in Pointe Noire during the period from January 1st, 2012 to December 31st, 2016 for duration of 5 years. 54 records of patients over 18 years of age with histological evidence were collected. The variables studied were: age, level of education, time to presentation, telltale sign, stage of extension, histological type, and histological grade. Chi-square test was used to compare variables and groups. Results: At the end of this study, we collected 54 files of breast cancer patients from 150 patients hospitalized in the Cancer Department. The frequency of breast cancer was 36%. The average age was 50 ± 13.6 years;the extremes were 27 years and 79 years. The most represented age group was from 37 to 40 years old with a percentage of 28%. The patient’s level of study was primary in the majority of cases (57%). The most represented histological type was invasive ductal carcinoma, (100%). The majority of patients arrived at advanced stages 44.4% and metastatic stages 26%. Patients were treated in most of cases by chemotherapy (82%), surgery (42%) and radiotherapy (10%). There was a correlation between time of presentation and stage of extension. Conclusion: Breast cancer is the first cancer of the woman in Pointe Noire. Patients arrive at advanced stages;the most common histological type is invasive ductal carcinoma. The presentation time is correlated with the extension stage. These results suggest the establishment of a cancer control program in developing countries.

关键词： Epidemiological Clinical Therapeutic Breast Cancer Pointe Noire

Improving the hard magnetic properties by intragrain pinning for Ta doped nanocrystalline Ce-fe-B alloys

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Journal of materials Science & Technology 2019年第9期35卷 1877-1885页

作者： J.S.Zhang W. Li X.f. Liao H.Y. Yu L.Z. Zhao H.X. Zeng D.R. Peng Z.W. Liu School of materials Science and Engineering South China University of TechnologyGuangzhou510640China Innovative Center for Advanced materials (ICAm) Hangzhou Dianzi UniversityHangzhou310012China

To develop Ce based permanent magnets with high performance/cost ratio, Ta doping is was employed to enhance the magnetic performance of Ce-fe-B alloys. for melt spun Cei7fe78-xTaxB6 (x = 0-1) alloys, the coercivity Hc increases from 439 to 553 kA/m with increasing x value from 0 to 0.75. microstructure characterizations indicate that Ta doping is helpful for grain refinement. A second phase of TaB2 is observed in Ce17fe77.25Tao.75B6 alloy, which acts as the pinning center of the magnetic domains, resulting in the change of coercivity mechanism.f.om nucleation type to nucleation +pinning type. The micromagnetic simulation confirms that non-magnetic particles within hard magnetic phase can increase the demagnetization field around them and it is crucial for preventing the further magnetization reverse by pinning effect. Take the advantage of Ta doping for enhancing the coercivity, Ce content of Ce-fe-B alloy can be further cut down to increase the remanence Jr due to the reduced volume fraction of Cefe2 phase and increased fe/Ce ratio. As a result, a good combination of magnetic properties with Hc = 514 kA/m, Jr = 0.49 T, and the maximum energy product (BH)max = 36 kJ/m^3 have been obtained in Ce15fe79.25Tao.75B6 alloy. It is expected that the present work can serve as a useful reference for designing new permanent magnetic materials with low-cost.

关键词： melt-spinning Permanent magnets Second phase Coercivity mechanism Thermal stability

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河流沉积物和河水中的铀钍系核素

世界核地质科学 1987年第3期 40-45页

作者： m.R.Scott P.f.Salter 陈国梁

河流取样工作课题,在1979年只限于从Rio Grande,密西西比和Suwannee三条河中取大体积悬浮沉积样品。这三条河分别流向干旱地带、温带和亚热带区域。大的河流沉积样品是按ORO-3852-29报告中所述方法收集的。

关键词：沉积物样品 Ra Th 河流沉积陆相沉积河水悬浮沉积物海洋沉积物铀含量核素

Limits on rough-particle sizing with low-defocus interferometric imaging

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Particuology 2015年第5期13卷 52-58页

作者： m.Brunel L.Ouldarbi H.Shen G.Grehan S.Cetmellec Dpartement Optique et Lasers CORIA-UMR CNRS 6614Universite de RouenAvenue de I'UniversiteBP 12F-76801 Saint-Etienne du Rouvray Cedex.France

We present a rigorous theoretical model for the influence of the aperture in interferometric out-of-focus imaging. We investigate the role of this effect on the properties of speckle-like patterns generated by irregular, rough particles. finally, we determine the conditions under which these patterns are no longer representative of particle size but of the aperture itself and the defocus parameter.

关键词： lnterferometric out-of-focus imaging Irregular rough particles Generalized Huygens-fresnel integrals

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