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A 330-500 GHz Zero-Biased Broadband Tripler Based on Terahertz Monolithic Integrated Circuits 被引量:3
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作者 任田昊 张勇 +4 位作者 延波 徐锐敏 杨成樾 周静涛 金智 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期31-34,共4页
A 330-500 GHz zero-biased broadband monolithic integrated tripler is reported. The measured results show that the maximum efficiency and the maximum output power are 2% and 194μW at 348 GHz. The saturation characteri... A 330-500 GHz zero-biased broadband monolithic integrated tripler is reported. The measured results show that the maximum efficiency and the maximum output power are 2% and 194μW at 348 GHz. The saturation characteristic test shows that the output i dB compression point is about -8.5 dBm at 334 GHz and the maximum efficiency is obtained at the point, which is slightly below the 1 dB compression point. Compared with the conventional hybrid integrated circuit, a major advantage of the monolithic integrated circuit is the significant improvement of reliability and consistency. In this work, a terahertz monolithic frequency multiplier at this band is designed and fabricated. 展开更多
关键词 InP InGaAs A 330-500 GHz Zero-Biased Broadband Tripler based on Terahertz Monolithic Integrated Circuits dBm SBD
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SELECTING CLUSTER MODEL IN Sn - BASED SOLDER ALLOY DESIGN WITH DV - X_α CALCULATION METHOD
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作者 C. Q. Wang and W. F. Feng National ho. of Advanced welding Technolgy, HIT, Harbin 150001,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期84-88,共5页
Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have ... Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have been investigated by employing DV - Xa method, in which different cluster models were adopted to calculate electron structure.It is proved that some regulations must be taken into ac- count in order to carry out alloy design calculation successfully,which are described in this paper in detail. 展开更多
关键词 Cluster model Sn - based alloy design DV - X_a calculation method DOS
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Preparation and the Pore Structure of Viscose-based Activated Carbon Fibers Treated with Pretreatment Reagents
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作者 罗艳 黄永辉 《Journal of China Textile University(English Edition)》 EI CAS 2000年第2期16-18,共3页
The viscose rayon was pretreated with four different pre-treatment reagents respectively, and the preparation ofactivated carbon fibers (ACF) was performed undersame carbonizing and activating conditions. The poresize... The viscose rayon was pretreated with four different pre-treatment reagents respectively, and the preparation ofactivated carbon fibers (ACF) was performed undersame carbonizing and activating conditions. The poresize distribution, the specific surface area, and the porestructure parameter of these viscose - based ACF werestudied by using quartz spring balance BET- weightmethod. The experiment result indicates that the poresize distribution and the pore structure parameter ofACF is varied by using different pretreatment reagents. 展开更多
关键词 PRETREATMENT REAGENT VISCOSE - based ACF PORE size PORE structure specific surface area
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GRAPHICAL COMPUTING METHOD ON FOUR-BAR LINKAGE(1)——Inflexion Circle,Focal Axis,Ball's Point,Centering-point Curve and Circling-point Curve For Four ISPs,Coupler Curves Based on Ball's Points——
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作者 周晋康 《苏州大学学报(工科版)》 CAS 1992年第S2期27-34,共8页
By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we... By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we make aspecial study about centering- point curve and circling- point curve and couplercurves based on Ball’s points. 展开更多
关键词 Ball’s POINT centering - POINT CURVE and CIRCLING CURVE four ISPS Coupler curves based on BALLS Points
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NEW SOLID BASE DERIVED FROM AIPO4-5 SUPPORTED KF
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作者 Jian Hua ZHU Qin Hug XU Hideshi HATTORI(Chemistry Department, Nanjing University.Nanjing 210093,China.)(Centre for Advanced Research of Energy Technology, Hokkaido University,Sapporo 060.Japan) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第7期671-674,共4页
Dispersion of KF on AlPO4-5 molecular sieve created basic sites and caused 1654 cm- band of bidentate carbonate in CO2 adsorption.After pre-treated above 823K. 5%KF/AlPO4-5exhibited basic catalytic activity in the iso... Dispersion of KF on AlPO4-5 molecular sieve created basic sites and caused 1654 cm- band of bidentate carbonate in CO2 adsorption.After pre-treated above 823K. 5%KF/AlPO4-5exhibited basic catalytic activity in the isomerization of butenes at 273K. and the activity increasedwith the pre-treatment temperature up to 923K. 展开更多
关键词 NEW SOLID base DERIVED FROM AIPO4-5 SUPPORTED KF
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Biological Evaluation of New Schiff Bases: Synthesized from 4-Amino-3,5-dimethyl-1,2,4-triazole, Phenathroline and Bipyridine Dicarboxaldehydes
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作者 Md. Shafiqul Islam Mohammad R. Karim +2 位作者 William Boadi Seyi Falekun Aminul H. Mirza 《Advances in Biological Chemistry》 2016年第6期180-192,共13页
Four new Schiff bases with promising anticancer activity have been synthesized from 4-amino-3,5-dimethyl-1,2,4-triazole and di-pyridyl-aldehydes. Structures have been established by various spectroscopic methods. The ... Four new Schiff bases with promising anticancer activity have been synthesized from 4-amino-3,5-dimethyl-1,2,4-triazole and di-pyridyl-aldehydes. Structures have been established by various spectroscopic methods. The compounds were tested in vitro to study their cytotoxicity and anti-oxidative activity in human lung carcinoma (A549), breast carcinoma (BT549), prostate adenocarcinoma (PC3) and mouse preadipocytes (3T3-L1) cells. Compound 1 was found to increase Glutathione (GSH) level slightly in all four cell lines. Compound 4 showed better selectivity and cytotoxicity against both BT549 and A549 cells compared to the anticancer drug tamoxifen. With the exception of compound 4 which reduced GSH levels in A549 and BT549, all other compounds maintained GSH levels in comparison to their respective controls. 展开更多
关键词 [2 2’-Bipyridine]-5 5’-dicarboxaldehyde Schiff bases Anticancer GLUTATHIONE ANTI-BACTERIAL
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RE Production Base Will Be Built in Baotou During 2006-2010
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《China Rare Earth Information》 2005年第11期3-3,共1页
关键词 2010 RE Production base Will Be Built in Baotou During 2006-2010 BE
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含香豆素骨架水杨醛Schiff base荧光材料的制备及光谱性能研究 被引量:4
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作者 冯雷 禹兴海 +2 位作者 金淑萍 徐建斌 刘娜 《化学试剂》 CAS CSCD 北大核心 2012年第3期257-260,共4页
以间苯二酚和乙酰乙酸乙酯为原料,草酸做催化剂,在无溶剂的条件下,经Pechmann反应催化合成了7-羟基-4-甲基香豆素,再经硝化、还原得到3-氨基7-羟基-4-甲基香豆素。利用3-氨基7-羟基-4-甲基香豆素与水杨醛缩合反应,制备了新型的含香豆素... 以间苯二酚和乙酰乙酸乙酯为原料,草酸做催化剂,在无溶剂的条件下,经Pechmann反应催化合成了7-羟基-4-甲基香豆素,再经硝化、还原得到3-氨基7-羟基-4-甲基香豆素。利用3-氨基7-羟基-4-甲基香豆素与水杨醛缩合反应,制备了新型的含香豆素骨架水杨醛Schiff base衍生物,其结构由IR、1HNMR和元素分析确证。通过研究化合物紫外吸收光谱及荧光光谱发现该化合物具有优异光学活性。 展开更多
关键词 7-羟基-4-甲基香豆素 水杨醛 SCHIFF base 光学性能
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苯胺α-呋喃甲醛双齿单希夫碱过渡金属配合物的合成和表征
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作者 南光明 吴进 《西昌学院学报(自然科学版)》 2005年第2期71-73,共3页
本文合成了单希夫碱配体-苯胺缩α-呋喃甲醛,使用过渡金属化合物FeCl3.6H2O、MnCl2.4H2O、CoCl2·6H2O、NiCl·26H2O与之配合生成了四种配合物,并用1HNMR、IR及元素分析等测试技术予以表征。
关键词 SCHIFF base 配合物 苯胺 α-呋喃甲醛 过渡金属
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π-旋转LDPC码译码算法及其量化研究 被引量:1
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作者 刘文焘 李强 李少谦 《信息技术》 2005年第11期38-40,43,共4页
通过仿真分析论述了Normalized BP-Based算法对于π-旋转LDPC码具有很好的译码性能,并对此算法它进行了定点分析,从仿真结果可知,使用BPSK调制时,在白高斯噪声信道下,Normalized BP-Based译码算法使用正确的量化方案时可以获得和浮点几... 通过仿真分析论述了Normalized BP-Based算法对于π-旋转LDPC码具有很好的译码性能,并对此算法它进行了定点分析,从仿真结果可知,使用BPSK调制时,在白高斯噪声信道下,Normalized BP-Based译码算法使用正确的量化方案时可以获得和浮点几乎一致的性能。 展开更多
关键词 π-旋转LDPC码 量化 Normalized BP—based算法 误码率
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Synthesis and Crystal Structure of a Co(II) Complex with Schiff Base and Imidazole Ligand 被引量:1
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作者 WU Lian-Bin HU Zi-Qiang LAI Guo-Qiao 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第5期567-571,共5页
The title compound, [Co(C3H4N2)2(C22H18N2O4)]·5H2O (Mr = 659.56), has been prepared and its crystal structure was determined by X-ray diffraction method. The crystal belongs to monoclinic, space group P21/n... The title compound, [Co(C3H4N2)2(C22H18N2O4)]·5H2O (Mr = 659.56), has been prepared and its crystal structure was determined by X-ray diffraction method. The crystal belongs to monoclinic, space group P21/n, a = 9.6808(2), b = 26.7204(5), c = 12.7993(3) A, β = 100.9340(10)°, V= 3250.75(12) A^3, Z = 4, Dc = 1.348 g/cm^3,μ = 0.586 mm^-1, F(000) = 1380, S = 1.131, R = 0.0689 and wR = 0.1883 for 4782 observed reflections (Ⅰ 〉 2σ(Ⅰ)). The title crystal consists of Co(Ⅱ) complex and lattice water molecules. The Co(Ⅱ) complex assumes a distorted octahedral coordination geometry, formed by one Schiff base dianion phenylenediamine-3-methoxysali-cylaldehyde and two imidazole ligands. The π-π stacking interaction occurs between nearly parallel benzene rings of the neighboring complexes. 展开更多
关键词 cobalt(Ⅱ) complex Schiff base crystal structure π-π stacking
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Synthesis and Crystal Structure of a New Nickel(II) Complex with Unsymmetric Quadridentate Schiff Base Containing Oxime 被引量:1
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作者 ZHANGGuo-Juan FENGYun-Long GAOShan 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第4期454-456,共3页
The title complex, C18H15N3NiO3, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group Cc with a = 10.939(2), b = 22.909(5), c = 6.907(1) ?, β = 11... The title complex, C18H15N3NiO3, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group Cc with a = 10.939(2), b = 22.909(5), c = 6.907(1) ?, β = 116.75(3)°, V = 1545.7(5) ?, Z = 4, Mr = 380.04, F(000) = 784, Dc = 1.633 g/cm3 and μ(MoKα) = 1.279 mm–1. The structure was refined to R = 0.0472 and wR = 0.0893 for 2571 observed reflections with I > 2σ(I). The absolute structure Flack parameter X is 0.01(2). In this crystal structure, strong face-to-face π-π stacking interactions between adjacent molecules lead to a one-dimensional chain structure. 展开更多
关键词 nickel(II) complex Schiff base OXIME crystal structure π-π stacking interaction
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Kinetic, electronic properties and conductivity studies of ((12Z)N-(5Z)-1-bromo-5-(phenylimino)-1H-pyrrol-2(5H)-ylidene benzenmine {ArN(CNBrCCHCH)NAr} (Ar = C6H5) 被引量:1
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作者 Salem Et. Ashoor Noori Y. Salman 《Journal of Chemistry and Chemical Engineering》 2009年第10期51-56,共6页
Kinetic and conductivity of new Schiff bases compounds such ((12Z)N-(5Z)-1-bromo-5-(phenylimino)-1H- pyrrol-2(5 H)-ylidene)benzenamine {ArN(CNBrCCHCH)NAr} (Ar = C6H5) incorporating the chelating diamino ... Kinetic and conductivity of new Schiff bases compounds such ((12Z)N-(5Z)-1-bromo-5-(phenylimino)-1H- pyrrol-2(5 H)-ylidene)benzenamine {ArN(CNBrCCHCH)NAr} (Ar = C6H5) incorporating the chelating diamino has been studied in this paper and was found a second order of this reaction. Electronic Properties using hyperchem program study has been improved for this compound such angel and bond distance, and then this compound was defining as electric conductivity and did prove to be useful for conduclively compound. 展开更多
关键词 Schiff bases compounds ((12Z)N-(5Z)-1-bromo-5-(phenylimino)- 1H-pyrrol-2(5H)-ylide ne)benzenamine chelating diamino: electronic properties
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Synthesis and Crystal Structure of 4-Nitro-2-[(2-diethylaminoethylimino)methyl]phenol
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作者 WANG Feng-Wu WEI Yi-Jun ZHU Qi-Yong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第10期1179-1182,共4页
The title Schiff base compound C13H19N3O3 synthesized by the condensation of equimolar 5-nitrosalicylaldehyde and N,N-diethylethane-1,2-diamine consists of two independent molecules. The compound was characterized by ... The title Schiff base compound C13H19N3O3 synthesized by the condensation of equimolar 5-nitrosalicylaldehyde and N,N-diethylethane-1,2-diamine consists of two independent molecules. The compound was characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system, space group Pbca with a = 13.151 (3), b = 20.609(4), c = 20.991 (4) °A, Z = 16, V = 5689(2) °A^3, Dc = 1.239 g/cm^3, Mr = 265.31, λ(MoKa) = 0.71073 °A, μ= 0.089 mm^-1, F(000) = 2272, R = 0.0732 and wR = 0.1454. A total of 5264 unique reflections were collected, of which 2023 with I 〉 2σ(I) were observed. As expected, the molecule adopts trans configuration about the C=N double bond. The molecules in the crystal are linked through intermolecular hydrogen bonds and π-π interactions, forming a 3-D network. 展开更多
关键词 Schiff base crystal structure hydrogen bonds π-π interactions
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Green fuel from coal via Fischer-Tropsch process: scenario of optimal condition of process and modelling
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作者 Hossein Atashil Somayyeh Veiskarami 《International Journal of Coal Science & Technology》 EI 2018年第2期230-243,共14页
Extracting, transportation and the using from fossil fuels can damage to the hydrosphere, the biosphere and the Earth's atmosphere. But humans always need to this valuable substance. The production of oil derivatives... Extracting, transportation and the using from fossil fuels can damage to the hydrosphere, the biosphere and the Earth's atmosphere. But humans always need to this valuable substance. The production of oil derivatives by means of forest waste and coal through the Fischer-Tropsch process is an appropriate solution for the cleanliness of all parts of the environment. For the production of favorite products by the synthesis of Fischer-Tropsch, the performance of the catalyst under different operating conditions should be predictable. For this reason, in this paper, eight mathematical models were determined for the selectivity of five products of methane, light hydrocarbons, gasoline, diesel and wax based on three factors of reduction temperature, time on stream, and He/CO ratio inlet gas on iron-based catalyst. The results showed that the reduction temperature factor had the most effective on the selectivity of hydrocarbon products, exception diesel, so that the increase of the reduction temperature led to increase of the selectivity of methane, light hydrocarbons, gasoline and reduce of the degree of selectivity of the wax and vice versa. For the diesel selectivity, factor of the He/CO ratio inlet gas was the most effective than other factors. 展开更多
关键词 Fischer-Tropsch process - Selectivity model Iron based catalyst BIOMASS Oil derivatives
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The Business of Managing Risk and Network Security:An Exploration of Knowledge Transfer Issues within the Context of Data Security and Countermeasure Trade Offs
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作者 Jim MorrisVice President(Trident Data Systems 12701 Fairlakes Circle.Suite 350 Fairfax,VA22033 USA)Jim SnaithPrincipal Lecturer In Business Information Systems(Area of Finance Accounting and Business Information SystemsSouth Bank University Business Schoo 《计算机工程》 CAS CSCD 北大核心 1996年第S1期68-81,共14页
The contemporary environment within which command,control,communications,computers and intelligence (C4I platforms exist, have a number of characteristics. These characteristics may be most obviously identified as int... The contemporary environment within which command,control,communications,computers and intelligence (C4I platforms exist, have a number of characteristics. These characteristics may be most obviously identified as interconnectivity, international networking, speed of data transfer, the compact nature of electronic information and rapidly changing technology. Information security professionals employ a variety of approaches in order to counter risks within this complex and fluid environment. The gamut of potential security activities ranges form access control through a variety of auditing techniques to secure data communications. This field is broad and well documented. Indeed, the discipline of network risk management and data security is both well developed and sophisticated.This paper addresses twin themes:i.The fundamental issue of the method by which specific approaches are employed. This is a precursor to the adoption of an eventual strategy.ii.The crucial issues revolving around the 展开更多
关键词 VALUE - The perceived or intrinsic WORTH of AN ASSET based on PURCHASE or development COSTS operations COSTS WORTH of information processed recovery expenes or any combination thereof. VALUE is relative to point- of- view.Threat- AN cvent
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Synthesis of Folate-Appended <i>β</i>-Cyclodextrin Using Phenanthroline as Linker for Cancer Targeting Drug Delivery
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作者 Nadim S. Russel Punam K. Paul +1 位作者 Mohammad Karim Byeongwoon Song 《International Journal of Organic Chemistry》 2019年第1期47-66,共20页
Here we have synthesized cancer targeting drug delivery system that contains β-cyclodextrin as a drug carrier and folic acid as a targeting ligand. Folic acid was selected as a cancer targeting ligand because folic a... Here we have synthesized cancer targeting drug delivery system that contains β-cyclodextrin as a drug carrier and folic acid as a targeting ligand. Folic acid was selected as a cancer targeting ligand because folic acid receptors are highly expressed in a variety of tumor types. β-cyclodextrin and folic acid were connected through a linker [1,10-phenanthroline or 5-(hydroxymethyl) furfural]. β-cyclodextrin and folic acid were attached to the linker by formation of Schiffbase and ester, respectively. Our targeted synthetic products were confirmed by NMR, Mass and IR spectroscopy. We anticipate that our synthetic products can confer cancer cell-specific drug delivery as well as desired properties such as nanoparticle formation. 展开更多
关键词 Schiff base β-Cyclodextrin p-Toluenesulfonylchloride Ethylenediamine Folic Acid 2 9-Dimethyl-1 10-PHENANTHROLINE Hemi-Hydrate 5-(Hydroxymethyl-2-Furaldehyde)
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一种分布式CBR工具研究与设计 被引量:5
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作者 周凯波 金斌 冯珊 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2005年第9期33-35,共3页
以复杂产品概念设计为应用研究背景,论述了如何在Java环境下进行CBR(Case-Based Reasoning)工具的研究、设计与开发.CBR工具的设计面向通用复杂产品设计的原则,研究了工具系统整体架构设计、基于XML的案例库设计和基于XML的案例结构设计... 以复杂产品概念设计为应用研究背景,论述了如何在Java环境下进行CBR(Case-Based Reasoning)工具的研究、设计与开发.CBR工具的设计面向通用复杂产品设计的原则,研究了工具系统整体架构设计、基于XML的案例库设计和基于XML的案例结构设计.整个系统充分利用Java语言适合分布式计算、面向对象的特性,建立网络计算环境和多级CBR推理机制进行更加细化推理.研究结果表明:所设计的工具软件,可使处于不同层次、不同阶段、分布在不同地点的概念设计活动实现及时协调和实时信息交互,最终达到缩短产品开发时间、提高产品设计质量的目的,同时该工具软件还可推广应用到其他复杂问题求解领域. 展开更多
关键词 基于案例推理 JAVA XML 案例检索 案例知识表示
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PBL联合CBL教学法提高护理本科实习生临床能力的效果评价 被引量:28
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作者 张凤勤 陈红宇 +1 位作者 丁娟 陈淳 《护理管理杂志》 2016年第8期589-591,共3页
目的探讨PBL联合CBL教学法在护理本科实习生临床能力培养中的应用效果。方法选取2013年7月至2014年3月102名护理本科实习生为对照组,2014年7月至2015年3月108名护理本科实习生为观察组,对照组采用常规教学法进行临床能力培养,观察组采用... 目的探讨PBL联合CBL教学法在护理本科实习生临床能力培养中的应用效果。方法选取2013年7月至2014年3月102名护理本科实习生为对照组,2014年7月至2015年3月108名护理本科实习生为观察组,对照组采用常规教学法进行临床能力培养,观察组采用PBL联合CBL教学法进行临床能力培养。实习结束前1个月采用临床能力自我评价表对两组护理本科实习生进行测评,并对其考核成绩进行比较。结果观察组考核成绩高于对照组,两组比较差异具有统计学意义(P<0.01)。观察组护理本科实习生临床能力总分为(439.55±23.18)分,高于对照组(414.28±19.52)分,差异具有统计学意义(P<0.01)。结论 PBL联合CBL教学法不仅使理论与实践有效结合,同时也提高了护理本科实习生的临床能力,使其更好地适应护理学科及临床护理的要求。 展开更多
关键词 PBL CBI. 护理本科生 临床能力
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基于知识的产品制造过程能耗的计算与预测 被引量:9
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作者 宫运启 吕民 +1 位作者 王刚 付宜利 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第2期14-19,共6页
为了估算新产品制造过程中的能耗,提出了基于知识的能耗预测方法.首先,应用本体技术使能消的计算和管理更清晰和明确,建立了能耗知识的语义模型并指出其语义表示方法.其次,提出了针对能耗预测特点的工艺实例检索过程及相似实例结果的重... 为了估算新产品制造过程中的能耗,提出了基于知识的能耗预测方法.首先,应用本体技术使能消的计算和管理更清晰和明确,建立了能耗知识的语义模型并指出其语义表示方法.其次,提出了针对能耗预测特点的工艺实例检索过程及相似实例结果的重用方法.最后,应用神经网络技术建立了针对加工参数的能耗预测模型,并以叶片加工为例进行了应用验证.从而形成了从全局视角到工艺过程再到工序的能耗预测层次框架,并对原型系统的开发及应用进行了说明. 展开更多
关键词 能耗预测 离散制造业 本体 实例推理 神经网络
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