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陶瓷材料的显微结构设计与自补强韧化组元的生成机理 被引量:10
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作者 李建保 翟华嶂 +1 位作者 黎义 黄勇 《材料导报》 EI CAS CSCD 2001年第4期16-19,25,共5页
结合近期在陶瓷领域的一些主要成果,从物理化学角度,论述了在材料内部原位生成棒晶、板晶等补强韧化组元的几种形成机理及其应用。
关键词 原位全成 相图 棒晶 板晶 晶须 陶瓷材料 显微结构设计 自补强韧化组元 生成机理 调幅分解
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合成孔径雷达干涉成像技术及其应用 被引量:10
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作者 毛建旭 王耀南 夏耶 《系统工程与电子技术》 EI CSCD 北大核心 2003年第1期7-10,24,共5页
卫星合成孔径雷达干涉技术 (INSAR)通过对地面同一地区两次或多次平行观测成像得到的复图象对 ,可以获得精度达米级的数字高程模型和监测地表的厘米级形变。首先简单介绍了INSAR技术的发展历史 ,然后阐述了INSAR技术和D -INSAR技术的原... 卫星合成孔径雷达干涉技术 (INSAR)通过对地面同一地区两次或多次平行观测成像得到的复图象对 ,可以获得精度达米级的数字高程模型和监测地表的厘米级形变。首先简单介绍了INSAR技术的发展历史 ,然后阐述了INSAR技术和D -INSAR技术的原理及数据处理流程 ,同时给出了基于ERS - 1原始数据的实验结果。最后介绍了该技术在地形测量、地质灾害研究、极地监测、海洋表面监测等领域的应用。 展开更多
关键词 全成孔径雷达 差分干涉 雷达成像
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日粮中多不饱和脂肪酸(PUFA)对动物基因表达和脂肪细胞分化的调节 被引量:8
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作者 颜新春 汪以真 许梓荣 《饲料研究》 CAS 2001年第2期4-5,共2页
关键词 日粮 多不饱和脂肪酸 基因表达 脂肪细胞分化 调节因子 脂肪全成
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新酶抑制剂他唑巴坦的合成 被引量:2
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作者 陆导仁 崔峰波 +4 位作者 庞丹梅 徐月爱 褚敏 王枫 单达先 《浙江医科大学学报》 CSCD 1997年第2期52-56,共5页
以6-氨基青霉烷酸为原料,经10步反应合成了他唑巴坦钠。6-APA经重氮化、溴化转变为6α-溴代青霉烷酸(1),在二苯腙存在下用过氧醋酸氧化一步生成6-α溴代青霉亚砜酸二苯甲酯(2),再以锌粉还原得6,6-二氢青霉亚砜酸二苯甲酯(3... 以6-氨基青霉烷酸为原料,经10步反应合成了他唑巴坦钠。6-APA经重氮化、溴化转变为6α-溴代青霉烷酸(1),在二苯腙存在下用过氧醋酸氧化一步生成6-α溴代青霉亚砜酸二苯甲酯(2),再以锌粉还原得6,6-二氢青霉亚砜酸二苯甲酯(3),(3)与2-巯基苯骈噻唑共热得氮杂环丁酮二硫化物(4),(4)用无水氯化铜反应得2β-氯甲基青霉烷酸二苯甲酯(5),(5)在DMF中与叠氮化钠作用得混合物(6),(6)以高锰酸钾氧化后生成物用分级结晶分离出2β-叠氮甲基青霉砜酸二苯甲酯(7a),后者与乙炔环加成生成他唑巴坦二苯甲酯(8),接着用间-甲酚脱羧基保护基而得到他唑巴坦(9),最后以异辛酸钠成盐处理而得目的物(10)他唑巴坦钠。 展开更多
关键词 酶抑制剂 他唑巴坦钠 化学全成 抗生素 合成
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聚氨酯-环氧树脂复合乳液的合成与性能研究 被引量:2
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作者 郝新兵 张旭东 《中国涂料》 CAS 2008年第12期39-42,共4页
以六亚甲基二异氰酸酯(HDI)、聚醚二元醇(Diol-1000)、二羟甲基丙酸(DMPA)、乙二胺(EDA)和环氧树脂(E-20)等为主要原料制备了聚氨酯-环氧树脂复合乳液。研究了聚醚二元醇含量、羧基含量对复合乳液的稳定性及涂膜柔韧性和耐水性等的影响... 以六亚甲基二异氰酸酯(HDI)、聚醚二元醇(Diol-1000)、二羟甲基丙酸(DMPA)、乙二胺(EDA)和环氧树脂(E-20)等为主要原料制备了聚氨酯-环氧树脂复合乳液。研究了聚醚二元醇含量、羧基含量对复合乳液的稳定性及涂膜柔韧性和耐水性等的影响,用电化学阻抗技术研究了涂层的耐腐蚀性能。 展开更多
关键词 乳液 聚氨酯 环氧树脂 全成
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TCM在国有企业的实施
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作者 李焕荣 《当代财经》 CSSCI 北大核心 1997年第9期50-53,共4页
本文阐述了TCM全面成本管理的基本原理、基本特征和基本模型,并结合中国国有企业的实际,探讨实施的方法。
关键词 全成成本管理 国有企业 财务管理
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V_a~t图在脱铝Y型沸石孔结构分析中的应用 被引量:1
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作者 裴站芬 李宣文 罗冰 《石油炼制》 CSCD 1991年第12期52-55,共4页
测定了不同条件下脱铝的Y型沸石和一些催化剂的N_2吸附等温线,并将这些等温线转换成V_(a~t)(吸附量~层厚)图.由图计算了各样品的表面积和孔体积,其中用V_(a~t)图高相对压力的直线斜率计算样品的外表面积(定义为大于10.0nm孔的BET表面... 测定了不同条件下脱铝的Y型沸石和一些催化剂的N_2吸附等温线,并将这些等温线转换成V_(a~t)(吸附量~层厚)图.由图计算了各样品的表面积和孔体积,其中用V_(a~t)图高相对压力的直线斜率计算样品的外表面积(定义为大于10.0nm孔的BET表面积)还不曾见报道.对脱铝Y型沸石,从这条直线还可计算出改性过程中产生的二次孔的表面积和孔体积.文中选出有代表性的6种V_(a~t)图,并由此对6个样品的孔结构进行了分析.同时,用经典的毛细管冷凝法计算了一些样品的孔分布曲线,发现各样品的最可几孔半径都出现在2.0nm左右. 展开更多
关键词 全成沸石 脱铝 结构
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Electromagnetic holographic sensitivity field of two-phase flow in horizontal wells 被引量:2
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作者 张阔 吴锡令 +1 位作者 闫景富 蔡家铁 《Applied Geophysics》 SCIE CSCD 2017年第1期40-48,189,共10页
Electromagnetic holographic data are characterized by two modes, suggesting that image reconstruction requires a dual-mode sensitivity field as well. We analyze an electromagnetic holographic field based on tomography... Electromagnetic holographic data are characterized by two modes, suggesting that image reconstruction requires a dual-mode sensitivity field as well. We analyze an electromagnetic holographic field based on tomography theory and Radon inverse transform to derive the expression of the electromagnetic holographic sensitivity field (EMHSF). Then, we apply the EMHSF calculated by using finite-element methods to flow simulations and holographic imaging. The results suggest that the EMHSF based on the partial derivative of radius of the complex electric potential φ is closely linked to the Radon inverse transform and encompasses the sensitivities of the amplitude and phase data. The flow images obtained with inversion using EMHSF better agree with the actual flow patterns. The EMHSF overcomes the limitations of traditional single-mode sensitivity fields. 展开更多
关键词 electromagnetic holographic sensitivity field (EMHSF) holographic physical detection field finite-element method holographic imaging
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SYNTHESIS OF FINASTERIDE 被引量:1
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作者 李效军 方芳 +1 位作者 王晓季 陈立功 《Transactions of Tianjin University》 EI CAS 2001年第4期286-289,共4页
As a kind of substrate competition type 5α reductase inhibitor,finasteride is a promising medicine used in the clinical treatment of benign prostatic hyperplasia (BPH).In this paper,a new route for the synthesis of... As a kind of substrate competition type 5α reductase inhibitor,finasteride is a promising medicine used in the clinical treatment of benign prostatic hyperplasia (BPH).In this paper,a new route for the synthesis of finasteride from pregnenolone was proposed.Thus,pregnenolone was converted to finasteride in 10 steps,i.e.,ammoniumation,methoxylation,Oppenauer oxidation,hydrolyzation,cleavage of Δ 4 double bond by oxidation,ring closure by ammonia,hydrogenation of Δ 5 double bond,esterification with methanol,dehydrogenation of 1,2 position in A ring and Bodroux reaction.In this route,expensive reagent 2,2 dipyridyl disulfide commonly used in previous literature was avoided.All of the desired compounds were characterized by MS or/and NMR.The overall yield of finasteride was 13.67% based on pregnenolone. 展开更多
关键词 FINASTERIDE SYNTHESIS PREGNENOLONE
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Total Synthesis of Anisodine 被引量:1
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作者 吴艳芬 卢强 +1 位作者 吕雯 仉文升 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第1期13-17,共5页
Aim To design a practical synthetic route of anisodine. Methods Starting from3α-hydroxy-6β-acetyltropine, anisodine was synthesized in 11 steps. Result Anisodine wasobtainded with an overall yield of 2.6 % . Conclus... Aim To design a practical synthetic route of anisodine. Methods Starting from3α-hydroxy-6β-acetyltropine, anisodine was synthesized in 11 steps. Result Anisodine wasobtainded with an overall yield of 2.6 % . Conclusion Total synthetic route of anisodine wasachieved which may afford a possible route for commercial preparation of anisodine. 展开更多
关键词 ANISODINE tropine alkaloid total synthesis
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涂料用纯丙乳液合成的研究 被引量:4
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作者 张华腾 庾美月 《上海涂料》 CAS 2001年第4期8-10,共3页
通过对丙烯酸丁酯、甲基丙烯酸甲酯、丙烯酸三元共聚,观察不同的聚合工艺、单体配比、乳化剂用量、交联剂用量等对乳液性能的影响。
关键词 纯丙乳液 全成方法 丙烯酸酯类 性能 涂料 聚合工艺
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对正烷基氰基苯的合成 被引量:1
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作者 董兆恒 王户生 +1 位作者 刘骞峰 安忠维 《浙江化工》 CAS 2001年第3期27-27,共1页
以对正烷基苯甲酸为原料,经过氯化、氨解、脱水的方法,合成了对烷基氰基苯,得率88%。
关键词 液晶 有机合成 烷基氰基苯 烷基苯甲酸 全成 氯化 氨解 脱水
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2.5 Gbit/s monolithic ICs for optical fiber transmitter and receiver in 0.35 μm CMOS process
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作者 冯军 王志功 +5 位作者 王欢 李连鸣 黄璐 盛志伟 章丽 熊明珍 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期268-271,共4页
2.5 Gbit/s monolithic integrated circuits (ICs) for optical fiber transmitter and receiver in 0.35 μm CMOS (complementary metal-oxide-semiconductor transistor) process are presented. The transmitter, which includ... 2.5 Gbit/s monolithic integrated circuits (ICs) for optical fiber transmitter and receiver in 0.35 μm CMOS (complementary metal-oxide-semiconductor transistor) process are presented. The transmitter, which includes a 4: 1 multiplexer and a laser diode driver (LDD), has four 622 Mbit/s random signals as its inputs and gets a 2.5 Gbit/s driving signal as its output; the receiver detects a 2.5 Gbit/s random signal and gets four 622 Mbit/s signals at the output. The main circuits include a trans-impedance amplifier (TIA), a limiting amplifier, a clock and data recovery (CDR) unit, and a 1: 4 demultiplexer (DEMUX). Test results prove the logic functions of the transmitter to be right, and the 10% to 90% rise and fall times of transmitter's output data eye diagram are 211.1 ps and 200 ps, respectively. The sensitivity of the receiver is measured to be better than 20 mV. The root mean square jitter of the DEMUX's output data is 15.6 ps and that of the clock after 1: 4 frequency dividing is 1.9 ps. Two chips are both applicable to 2.5 Gbit/s optical fiber communication systems. 展开更多
关键词 optical fiber communication monolithic: transmitter RECEIVER
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Durability zonation standard of concrete structure design 被引量:5
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作者 金伟良 吕清芳 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期98-104,共7页
Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions an... Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions and importance of structures based on the theory of life cycle cost(LCC). First, the basic concept of DZS for concrete structure design is defined. Then the basic principles for DZS are established. The factors for zonation according to natural environmental conditions and structural importance are identified. The usefulness of DZS by citing a real application for concrete highway bridges in Zhejiang Province is demonstrated. Finally, durability regulations are provided accordingly to zonation. 展开更多
关键词 durability zonation standard concrete structure design zonation map life cycle cost
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Security integrated framework for semantic web based on social intelligence
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作者 孟庆华 丁永生 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期409-412,共4页
An integrated security framework for a semantic web is proposed based on the social intelligence of an individual's avoiding harm and preserving transaction logic-integrity. The framework extends the semantic web mod... An integrated security framework for a semantic web is proposed based on the social intelligence of an individual's avoiding harm and preserving transaction logic-integrity. The framework extends the semantic web model and controls the dynamic security of semantic web services, such as trust, logic and reasoning. It includes four layers, that is, a trust entrance layer, a social intelligence layer, a transaction layer, and a TCP/IP security protocols layer. The trust entrance layer deals with trustable features from users. Social intelligence layer is responsible for logical questions for a semantic web. The transaction layer carries out transaction reasoning. And the TCP/IP security protocols layer ensures security communication. These layers can cooperate to build closed-security-ring with different security grades. The integrated security framework provides an integrated security method for semantic web flow so that it is universal for various semantic web technologies. 展开更多
关键词 integrated security framework social intelligence closed-security-ring security-channel semantic web
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中型氨厂各种工艺类型装置的能耗分析 被引量:1
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作者 晋良雨 《中氮肥》 1990年第5期1-14,共14页
本文对氨厂各种类型装置的能耗情况进行了分析。井通过有用能的引入与分析、探讨了能节途径。
关键词 全成 装置 能耗 设备
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全程护理在减少尿动力检查中患者疼痛、焦虑的影响研究 被引量:1
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作者 甄桂新 王然然 《实用妇科内分泌电子杂志》 2017年第21期196-196,198,共2页
目的探究全程护理方法在减少尿动力检查中患者疼痛、焦虑的情况。方法将2016年1月~2017年1月在我院接受尿动力检查的120例患者作为研究对象,按照患者的入院顺序将患者分为实验组和对照组。给予对照组患者常规的护理干预;给予实验组患者... 目的探究全程护理方法在减少尿动力检查中患者疼痛、焦虑的情况。方法将2016年1月~2017年1月在我院接受尿动力检查的120例患者作为研究对象,按照患者的入院顺序将患者分为实验组和对照组。给予对照组患者常规的护理干预;给予实验组患者全面的护理干预。比较两组患者的疼痛感和焦虑值。结果两组患者在经过护理后心理焦虑值评分相比于治疗前均下降,其中实验组患者下降明显优于对照组。并且实验组患者的疼痛程度显著低于对照组,差异有统计学意义(P<0.05)。结论护理人员对患者进行尿动力学检查时,对患者采取全程护理方法可以有效降低患者的疼痛感,缓解患者的焦虑情绪,减轻患者的焦虑程度,值得在临床上推广使用。 展开更多
关键词 全成护理 尿动力检查 疼痛感 焦虑感
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Evaluation on Land Ecological Security in Hohhot Based on Principal Component Analysis
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作者 侯林春 王瑛璇 《Agricultural Science & Technology》 CAS 2017年第7期1255-1259,共5页
Based on the status of land ecological resources in Hohhot, 20 indexes covering nature, resource environment, economy and society were selected and the evaluation index system was established. With the principal compo... Based on the status of land ecological resources in Hohhot, 20 indexes covering nature, resource environment, economy and society were selected and the evaluation index system was established. With the principal component analysis, the land ecological security of Hohhot from 2009 to 2015 was analyzed. The results showed that the land ecological security of Hohhot was declining year by year in 2009-2015. Besides, per capital GDP and public green area, the proportion of in- dustry and the price index of agricultural and animal husbandry production materials were the key factors influencing the land ecological security of Hohhot. The key for protection of the land ecological security may lie in the protection of land quality and prevention of land degradation in farming and stock-breeding areas. 展开更多
关键词 Land ecological security Principal component FACTOR COUNTERMEASURES Hohhot
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Security investment and information sharing for complementary firms with heterogeneous monetary loss
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作者 蔡传晰 梅姝娥 仲伟俊 《Journal of Southeast University(English Edition)》 EI CAS 2017年第2期241-248,共8页
Two complementary firms' information sharing and security investment are investigated. When two complementary firms with heterogeneous assets are both breached, it is assumed that they suffer different losses which a... Two complementary firms' information sharing and security investment are investigated. When two complementary firms with heterogeneous assets are both breached, it is assumed that they suffer different losses which are associated with their information assets. Some insights about optimal strategies for the firms and the attacker are obtained by the game theory, which forms a comparison with those derived from substitutable firms, and those derived from complementary firms with homogenous loss. In addition, both the unit transform cost of investment and the extent of firms'loss affect the optimal strategies.Assuming that firms can control information sharing, security investments and both of them, respectively, the effect of the social planner is further analyzed on the information sharing, firms' aggregate defence, the aggregate attack and social total cost. Finally, some policy advice is provided through numerical simulation. Results show that firms are willing to choose security investment centrally rather than individually, but an intervention in information sharing by the social planner may not necessarily be preferable. 展开更多
关键词 complementary firm contest success function security investment information sharing leakage cost
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Integrated ABS/ASR/ACC System for the Car
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作者 刘昭度 卢江 +1 位作者 时开斌 安巍 《Journal of Beijing Institute of Technology》 EI CAS 2001年第3期326-330,共5页
The individual functions of ACC and ABS/ASR are described in the improvements of active safety while the road vehicles travel at a high speed. Being a logic extension of and many inherent connections with ABS/BSR, ACC... The individual functions of ACC and ABS/ASR are described in the improvements of active safety while the road vehicles travel at a high speed. Being a logic extension of and many inherent connections with ABS/BSR, ACC is easily integrated with ABS/ASR to form an integrated system by adding the headway distance? detecting device to the existing ABS/ASR system and expanding the ABS/ASR software. The algorithm flowcharts and control methods of the ABS/ASR/ACC are given. The advantages of the ABS/ASR/ACC system compared with those using the stand alone systems ABS, ASR and ACC are mentioned in details. 展开更多
关键词 ABS/ASR/ACC INTEGRATED road vehicle safety device
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