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基于Master Curve方法的A508-Ⅲ钢断裂韧性研究 被引量:5
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作者 方颖 李辉 +2 位作者 惠虎 贺寅彪 李培宁 《核动力工程》 EI CAS CSCD 北大核心 2011年第S1期31-34,共4页
进行了国产A508-Ⅲ钢在韧脆转变区的拉伸实验和夏比冲击实验,获得了A508-III钢在此区域的力学性能和夏比冲击功随温度的变化曲线。以夏比冲击功为28 J或41 J所对应的特征温度关联预估MasterCurve方法的试验温度,分别采用多温度试验法和... 进行了国产A508-Ⅲ钢在韧脆转变区的拉伸实验和夏比冲击实验,获得了A508-III钢在此区域的力学性能和夏比冲击功随温度的变化曲线。以夏比冲击功为28 J或41 J所对应的特征温度关联预估MasterCurve方法的试验温度,分别采用多温度试验法和单温度试验法获得12.7 mm厚三点弯曲试样[SE(B)试样]的Master Curve曲线,并对其参考温度T0进行有效性判定。结果表明,采用单温度及多温度法获得的T0基本一致,国产A508-Ⅲ钢断裂韧性参考温度约为-63℃。 展开更多
关键词 A508-Ⅲ钢 MASTER curve方法 断裂韧性 韧脆转变 ASMEKIC曲线
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Comparative study of CEA and CA19-9 in esophageal,gastric and colon cancers individually and in combination(ROC curve analysis) 被引量:56
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作者 Bhawna Bagaria Sadhna Sood +1 位作者 Rameshwaram Sharma Soniya Lalwani 《Cancer Biology & Medicine》 SCIE CAS CSCD 2013年第3期148-157,共10页
Objective: To determine the clinical serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9), individually and in combination, for the diagnosis of 50 healthy subjects and 150 cases ... Objective: To determine the clinical serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9), individually and in combination, for the diagnosis of 50 healthy subjects and 150 cases of esophageal, gastric, and colon cancers. Methods: The sensitivities of the two markers were compared individually and in combination, with specificity set at 100%. Receiver operating characteristic (ROC) curves were plotted. Results: Serum CEA levels were significantly higher in cancer patients than in the control group. The sensitivity of CEA was determined: in esophageal cancer, sensitivity=28%, negative predictive value (NPV)=61.72%, and AUC=0.742 (SE=0.05), with a significance level of P〈0.0001; in gastric cancer, sensitivity=30%, NPV=58.82%, and AUC=0.734 (SE=0.0S), with a significance level of P〈0.0001; in colon cancer, sensitivity=74%, NPV=79.36%, and AUC=0.856 (SE=0.04), with a significance level of P〈0.0001. The sensitivity of CA19-9 was also evaluated: in esophageal cancer, sensitivity=18%, NPV=54.94%, and AUC=0.573 (SE=0.05), with a significance level of P=0.2054. In gastric cancer, sensitivity=42%, NPV=63.29%, and AUC=0.679 (SE=0.05), with a significance level of P〈0.0011. In colon cancer, sensitivity=26%, NPV=57.47%, and AUC=0.S80 (SE=0.05), with a significance level ofP=0.1670. The following were the sensitivities of CEA/CA19-9 combined: in esophageal cancer, sensitivity=42%, NPV=63.29%, SE=0.078 (95% CI: 0.0159-0.322); gastric cancer, sensitivity=S8%, NPV=70.42%, SE=0.072 (9$% CI: -0.0866-0.198); and colon cancer, sensitivity=72%, NPV=78.12%, SE=0.070 (9S% CI: 0.137-0.415). Conclusion: CEA exhibited the highest sensitivity for colon cancer, and CA19-9 exhibited the highest sensitivity for gastric cancer. Combined analysis indicated an increase in diagnostic sensitivity in esophageal and gastric cancer compared with that in colon cancer. 展开更多
关键词 Carcinoembryonic antigen carbohydrate antigen 19-9 human Receiver operating characteristic curve sensitivity andspecificity
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Powell dynamic identification of displacement parameters of indeterminate thin-walled curve box based on FCSE theory 被引量:5
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作者 Jian Zhang Chu-Wei Zhou Jia-Shou Zhuo 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第3期452-460,共9页
The FCSE controlling equation of pinned thinwalled curve box was derived and the indeterminate problem of continuous thin-walled curve box with diaphragm was solved based on flexibility theory. With Bayesian statistic... The FCSE controlling equation of pinned thinwalled curve box was derived and the indeterminate problem of continuous thin-walled curve box with diaphragm was solved based on flexibility theory. With Bayesian statistical theory,dynamic Bayesian error function of displacement parameters of indeterminate curve box was founded. The corresponding formulas of dynamic Bayesian expectation and variance were deduced. Combined with one-dimensional Fibonacci automatic search scheme of optimal step size,the Powell optimization theory was utilized to research the stochastic identification of displacement parameters of indeterminate thin-walled curve box. Then the identification steps were presented in detail and the corresponding calculation procedure was compiled. Through some classic examples,it is obtained that stochastic performances of systematic parameters and systematic responses are simultaneously deliberated in dynamic Bayesian error function. The one-dimensional optimization problem of the optimal step size is solved by adopting Fibonacci search method. And the Powell identification of displacement parameters of indeterminate thin-walled curve box has satisfied numerical stability and convergence,which demonstrates that the presented method and the compiled procedure are correct and reliable.During parameters鈥?iterative processes,the Powell theory is irrelevant with the calculation of finite curve strip element(FCSE) partial differentiation,which proves high computation effciency of the studied method. 展开更多
关键词 Powell theory - Indeterminate curve box . Displacement parameters - Fibonacci search method.Flexibility theory
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MODELING THE STRESS-STRAIN CURVES UNDER DYNAMIC RECRYSTALLIZATION 被引量:1
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作者 W. Gao T. Sakai and H. Miura( Department of Mechanical Engineering and Intelligent Systems, The University of Electro - Communica- tions, Chofu, Tokyo 182 - 8585, Japan) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期349-358,共10页
An analytical model for dynamic recrystallization (DRX) is studied based on the relative grain size model proposed by Sakai and Jonas, and the characteristic flow behaviors under DRX are analyzed and simulated. Int... An analytical model for dynamic recrystallization (DRX) is studied based on the relative grain size model proposed by Sakai and Jonas, and the characteristic flow behaviors under DRX are analyzed and simulated. Introducing the variation of dynamic grain size and the heterogeneous distribution of disolo- cation densities densities under DRX,a simple method for modeling and simulating DRX processes is developed by using Laplace transformation theory. The results derived from the present model agree well with the experimental results in literatures. This simulation can reproduce a number of features in DRX flow behaviors, for example,single and multiple peak flow behaviors followed by a steady state flow, the transition between them, and so on. 展开更多
关键词 dynamic recrystallization computer simulation stress - strain curve single and multiple peaks
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Study on Antibacterial Activity of 2-Methyl-3-(methylthio)Pyrazine Against Three Strains of Spoilage Bacteria
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作者 Kun LI Guanghe ZHU +1 位作者 Danning FU Lele LI 《Agricultural Biotechnology》 2024年第1期74-77,共4页
Previous studies have shown that glycine and proline are pharmacophores that display antibacterial activity.In the present study,glycine and proline were derivated to diketopiperazine compounds by chemical synthesis m... Previous studies have shown that glycine and proline are pharmacophores that display antibacterial activity.In the present study,glycine and proline were derivated to diketopiperazine compounds by chemical synthesis method,and their antibacterial activities were evaluated by three strains of spoilage bacteria,Escherichia coli,Pseudomonas aeruginosa and Shewanella putrefaciens,and the relationship of their antibacterial activities and structures was also investigated.Uv-vis spectrophotometry was used to determine the growth curves of three kinds of active indicator bacteria.Minimum inhibitory concentration(MIC)was determined by micro broth dilution method.The results showed that 2-methyl-3-(methylthio)pyrazine had significant antibacterial activity against three strains of the bacteria,and its MIC was 1.25%.It indicates 2-methyl-3-(methylthio)pyrazine has the potential to be developed as a kind of preservative in future. 展开更多
关键词 2-Methyl-3-(methylthio)pyrazine Growth curve Minimum inhibitory concentration
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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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基于3,5-二溴水杨醛席夫碱镍配合物-氧化石墨烯电化学免疫传感器检测Anti-IgG含量的研究 被引量:2
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作者 赖丽燕 刘峥 +2 位作者 李巍 周昱 黄红霞 《分析科学学报》 CAS CSCD 北大核心 2014年第4期481-484,共4页
应用物理吸附法将羊抗人IgG抗原直接固定于3,5-二溴水杨醛席夫碱镍配合物-氧化石墨烯修饰的金电极表面,制备电化学免疫传感器。采用循环伏安法和交流阻抗法对传感器进行表征,结果表明该传感器适合检测Anti-IgG浓度。同时探讨了缓冲液pH... 应用物理吸附法将羊抗人IgG抗原直接固定于3,5-二溴水杨醛席夫碱镍配合物-氧化石墨烯修饰的金电极表面,制备电化学免疫传感器。采用循环伏安法和交流阻抗法对传感器进行表征,结果表明该传感器适合检测Anti-IgG浓度。同时探讨了缓冲液pH值、扫描速度、免疫反应温度、抗原与抗体配比对循环伏安峰电流的影响,结果表明在5-100mV/s扫速范围内,峰电流与扫速呈线性。孵育最优条件为25℃,h-IgG与Anti-IgG配比为1∶1。循环伏安法研究还表明Anti-IgG浓度在0.01-260μg/L范围内,线性关系良好,相关系数r^2=0.993,检出限(S/N=3)为0.006μg/L,据此建立了检测Anti-IgG浓度的新方法。 展开更多
关键词 氧化石墨烯 3 5-二溴水杨醛席夫碱镍配合物 anti—IgG 电化学免疫传感器
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信号分子IRAK1/4在antiβ-2GPI/β2GPI复合物诱导THP-1细胞表达TF中的作用探讨 被引量:1
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作者 文海平 周红 +4 位作者 许国莹 郭东琳 周芳 陈东东 解鸿翔 《中国免疫学杂志》 CAS CSCD 北大核心 2011年第4期295-299,共5页
目的:探讨IRAK1和IRAK4在antiβ-2GPI/β2GPI复合物诱导单核细胞株THP-1表达组织因子(TF)中的作用。方法:利用荧光定量PCR(Real-time PCR)、TF活性试剂盒分别检测THP-1细胞表达TF mRNA及TF活性;Western blot检测anti-β2GPI/β2GPI复合... 目的:探讨IRAK1和IRAK4在antiβ-2GPI/β2GPI复合物诱导单核细胞株THP-1表达组织因子(TF)中的作用。方法:利用荧光定量PCR(Real-time PCR)、TF活性试剂盒分别检测THP-1细胞表达TF mRNA及TF活性;Western blot检测anti-β2GPI/β2GPI复合物诱导THP-1细胞表达IRAK1、磷酸化-IRAK1(p-IRAK1)、IRAK4情况;观察IRAK1/4抑制物是否干预anti-β2GPI/β2GPI复合物诱导THP-1表达TF。结果:Antiβ-2GPI/β2GPI复合物(100μg/ml)诱导THP-1细胞表达TF显著增加(P<0.05 vs control);Antiβ-2GPI/β2GPI复合物(100μg/ml)刺激THP-1细胞表达IRAK1、p-IRAK1、IRAK4(蛋白)显著升高(P<0.05 vscontrol);IRAK1/4抑制物(50μmol/L)能够阻断antiβ-2GPI/β2GPI复合物(100μg/ml)诱导THP-1表达TF及IRAK1磷酸化的效应。结论:antiβ-2GPI/β2GPI复合物诱导THP-1细胞表达TF过程中,信号分子IRAK1/4被激活进而发挥重要作用。 展开更多
关键词 抗磷脂综合征 antiβ-2GPI/β2GPI IRAK1 IRAK4 组织因子
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Antilg i_1-E曲线上的示波伏安滴定法 被引量:3
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作者 郑建斌 朱俊杰 +1 位作者 毕树平 高鸿 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 1993年第5期627-629,共3页
i_1-E曲线示波伏安滴定法是一种新的灵敏、准确的滴定分析方法。为进一步提高滴定终点指示的灵敏度,本文在产生i_1-E曲线的线路中,增加了正反馈电路和反对数电路,并提出了Antilg i_1-E曲线上的示波伏安滴定法。用EDTA或EGTA滴定了Ga^(3+... i_1-E曲线示波伏安滴定法是一种新的灵敏、准确的滴定分析方法。为进一步提高滴定终点指示的灵敏度,本文在产生i_1-E曲线的线路中,增加了正反馈电路和反对数电路,并提出了Antilg i_1-E曲线上的示波伏安滴定法。用EDTA或EGTA滴定了Ga^(3+)、Cd^(2+)、Zn^(2+)、Ni^(2+)、Co^(2+)等离子,并测定了铜锰合金中的锰,效果较好。 展开更多
关键词 示波伏安滴定 双电解池 if-E曲线
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基于决策曲线分析抗RA33、IL-6及hs-CRP水平对类风湿关节炎治疗反应性的预测价值
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作者 耿学丽 赵春楠 +2 位作者 张泽智 刘艳伶 丁佩剑 《国际检验医学杂志》 CAS 2024年第12期1431-1434,1441,共5页
目的基于决策曲线分析抗类风湿关节炎-33(抗RA33)、白细胞介素-6(IL-6)及超敏C反应蛋白(hs-CRP)水平对类风湿关节炎(RA)患者治疗反应性的预测价值。方法选取2021年1月至2023年8月该院收治的102例RA患者,收集患者临床资料并检测其血清抗R... 目的基于决策曲线分析抗类风湿关节炎-33(抗RA33)、白细胞介素-6(IL-6)及超敏C反应蛋白(hs-CRP)水平对类风湿关节炎(RA)患者治疗反应性的预测价值。方法选取2021年1月至2023年8月该院收治的102例RA患者,收集患者临床资料并检测其血清抗RA33、IL-6及hs-CRP水平。使用甲氨蝶呤与依那西普治疗半年后,根据治疗反应性分为反应良好组与无反应组。采用Pearson相关分析RA患者抗RA33、IL-6、hs-CRP水平与RA疾病活动评分(DAS28)的相关性,多因素Logistic回归分析RA患者治疗无反应的影响因素。绘制受试者工作特征(ROC)曲线,分析抗RA33、IL-6、hs-CRP在RA无反应中的效能。采用决策曲线分析抗RA33、IL-6、hs-CRP单独与联合预测RA患者治疗无反应的净收益情况。结果治疗半年后,反应良好和中度的患者共80例(反应良好组),无效22例(无反应组)。反应良好组病程短于无反应组,DAS28评分低于无反应组(P<0.05)。反应良好组血清抗RA33、IL-6、hs-CRP水平低于无反应组(P<0.05)。Pearson相关分析显示,血清抗RA33、IL-6、hs-CRP水平与DAS28评分均呈负相关(P<0.05)。多因素Logistic回归分析结果显示,DAS28评分及抗RA33、IL-6、hs-CRP水平为RA患者治疗无反应的影响因素(P<0.05)。ROC曲线显示,血清抗RA33、IL-6、hs-CRP单独及联合预测患者治疗无反应的曲线下面积分别为0.729、0.814、0.831、0.948,三者联合的预测价值更高。决策曲线分析显示,在大多合理阈值范围内,血清抗RA33、IL-6、hs-CRP联合预测对RA患者治疗反应性的总体净收益高于单独预测的净收益。结论抗RA33、IL-6、hs-CRP水平与RA患者治疗反应性密切相关,三者联合预测治疗无反应的临床价值及净收益较高。 展开更多
关键词 类风湿关节炎 抗类风湿关节炎-33 白细胞介素-6 超敏C反应蛋白 决策曲线 治疗反应性
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三维Anti de Sitter空间中Lorentzian曲面的S_t^1×S_s^1-值光锥Gauss映射的奇点分类
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作者 于海鸥 高瑞梅 +1 位作者 孔令令 裴东河 《东北师大学报(自然科学版)》 CAS CSCD 北大核心 2010年第4期35-45,共11页
利用Arnol'd的Legendrian理论,对三维Anti de Sitter空间中Lorentzian曲面进行了研究.引入光维高度函数概念研究了三维Anti de Sitter空间Lorentzian曲面的S1t×S1s-值、光锥Gauss映射的奇点,进行了奇点分类,揭示了类光Causs-kr... 利用Arnol'd的Legendrian理论,对三维Anti de Sitter空间中Lorentzian曲面进行了研究.引入光维高度函数概念研究了三维Anti de Sitter空间Lorentzian曲面的S1t×S1s-值、光锥Gauss映射的奇点,进行了奇点分类,揭示了类光Causs-kronecker曲率之间的关系;并研究了Lorentzian曲面的一些基本几何性质. 展开更多
关键词 Lorentzian曲面 三维anti DE SITTER空间 St1×Ss1-值光锥Gauss映射 Lorentzian光维高度函数
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Study of photometric phase curve:assuming a cellinoid ellipsoid shape for asteroid(106)Dione 被引量:1
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作者 Yi-Bo Wang Xiao-Bin Wang +1 位作者 Donald E Pray Ao Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第9期61-70,共10页
We carried out new photometric observations of asteroid (106) Dione at three apparitions (2004, 2012 and 2015) to understand its basic physical properties. Based on a new brightness model, new photometric observat... We carried out new photometric observations of asteroid (106) Dione at three apparitions (2004, 2012 and 2015) to understand its basic physical properties. Based on a new brightness model, new photometric observational data and published data of (106) Dione were analyzed to characterize the morphology of Dione's photometric phase curve. In this brightness model, a cellinoid ellipsoid shape and three-parameter (H, G1, G2) magnitude phase function system were involved. Such a model can not only solve the phase function system parameters of (106) Dione by considering an asymmetric shape of an asteroid, but also can be applied to more asteroids, especially those without enough photometric data to solve the convex shape. Using a Markov Chain Monte Carlo (MCMC) method, Dione's absolute magnitude of H = 7.66+0.03-0.03 mag, and phase function parameters G1 = 0.682+0.077-0.077 and G2 = 0.081+0.042-0.042 were obtained. Simultaneously, Dione's simplistic shape, orientation of pole and rotation period were also determined preliminarily. 展开更多
关键词 ASTEROIDS general photometric phase curve -- asteroids individual (106) Dione - techniques: photometric - Markov Chain Monte Carlo method
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Influence of graphene on the anti-corrosion performance of epoxy-based coatings 被引量:1
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作者 DONG Ying LU Qiting YAO Qisheng 《Baosteel Technical Research》 CAS 2016年第3期15-20,共6页
In this work, graphene-modified epoxy-based anti-corrosion coatings were prepared and the influence of graphene on the anti-corrosion performance of the epoxy-based coatings was investigated with water contact angle t... In this work, graphene-modified epoxy-based anti-corrosion coatings were prepared and the influence of graphene on the anti-corrosion performance of the epoxy-based coatings was investigated with water contact angle test ,chemical solution immersion test, and electrochemical test. The water contact angle and chemical solution resistance of the epoxy-based coatings were improved with an increase in graphene content from 0 to 0.4%. These results prove that addition of graphene can significantly improve the hydrophobicity and impermeability of epoxy- based coatings. However, when the graphene content was increased to 0.5%, the performance of the epoxy-based coatings decreased because of graphene aggregation. Tafel polarization results show that graphene addition can significantly reduce the corrosion current density and corrosion potential of epoxy-based coatings, which enhance their anti-corrosion performance. 展开更多
关键词 GRAPHENE epoxy-based coating anti-corrosion performance Tafel polarization curve
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On the Construction of Deepening Anti - corruption Mechanism
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作者 Ding Huanxiang Xuliang 《学术界》 CSSCI 北大核心 2018年第3期260-272,共13页
It needs the foundation of system and the guarantee of organizational system for anti-corruption,but it is more necessary to build and form an effective anti-corruption mechanism,so that the anti-corruption can be rea... It needs the foundation of system and the guarantee of organizational system for anti-corruption,but it is more necessary to build and form an effective anti-corruption mechanism,so that the anti-corruption can be really put into practice. Anti-corruption mechanism refers to a organic operation system of the interaction,interconnection and constraint between the constituent elements( parts) and elements of national anti-corruption,and as a system,anti-corruption mechanism should have the characteristics of system aticness,comprehensiveness,transparency,legalization,public participation,scientific dynam ic,and internationalism. The construction of deepening anti-corruption mechanism is the need for reconstructing the ruling legitimacy of the party and the governm ent. Adhering to the principle of treating both root causes and symptoms is necessary in the construction of anti-corruption m echanism,com bating and punishing corruption is an important part of anti-corruption,and the prevention and control of corruption is the basic project of anti-corruption. Therefore,the construction of prevention and control mechanism in the anti-corruption mechanism has a more far-reaching significance. 展开更多
关键词 anti - CORRUPTION MECHANISM CONSTRUCTION CONNOTATION and definition val-ue analysis prevention and control MECHANISM
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Comparison of the Radar Receiver Anti-Jamming Circuits Performance
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作者 Shuhua Li Baopeng Li 《World Journal of Engineering and Technology》 2017年第4期152-158,共7页
This paper researches on some key technologies of anti-jamming of an air-borne radar receiver, the automatic testing of AGC, IAGC and multi-filtering under one million noisy pulses by the computer simulation system. T... This paper researches on some key technologies of anti-jamming of an air-borne radar receiver, the automatic testing of AGC, IAGC and multi-filtering under one million noisy pulses by the computer simulation system. The system tests the width of the jamming pulse whose width is 100% bigger, 60% bigger and 100% smaller than the Radar signal’s respectively and show the SNR curve. 展开更多
关键词 Multi-Filtering anti-JAMMING CIRCUITS SNR curve
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Anti-Bacterial and Flame Retardant for Cotton Fabric by One-Bath Finishing
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作者 朱平 隋淑英 +1 位作者 王炳 孙铠 《Journal of China Textile University(English Edition)》 EI CAS 1998年第2期82-84,共3页
A research on the process of cotton fabric flame-re-tarding,anti-bacterial finishing and one-bath finish-ing of anti-bacterial and flame-retarding is discussed.The flame retardant agent was phosphorous-contained,and t... A research on the process of cotton fabric flame-re-tarding,anti-bacterial finishing and one-bath finish-ing of anti-bacterial and flame-retarding is discussed.The flame retardant agent was phosphorous-contained,and the bacteriostatic finishing agent named SFR-1 wassynthesized.The flame retardancy of the fabric finishedcan meet the DOC FF3-71 Children Sleepwear Stan-dard.Its bacterial inhibiting capacity can meet and ex-ceed the requirements of similar products 展开更多
关键词 cotton fabric flame - RETARDING FINISHING anti - BACTERIAL FINISHING one - BATH
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Testing of Anti-stripping Property of Friction Spun Core Yarn
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作者 丁辛 宋允 《Journal of China Textile University(English Edition)》 EI CAS 1998年第3期66-69,共4页
Friction spun core yarn has two components: filament core and staple fiber sheath. Under axial rubbing action, the failure mode of the core yarn is the stripping of the sheath from the core. This paper introduces a me... Friction spun core yarn has two components: filament core and staple fiber sheath. Under axial rubbing action, the failure mode of the core yarn is the stripping of the sheath from the core. This paper introduces a method to test the anti - stripping property of the core yarn. With a modified Universal Testing Machine, the stripping resistance of friction spun core yarn can be continuously measured. Some factors Influencing the measurements are discussed in detail. The testing results are compared with those from a Y731 Yarn Abrasion Tester and fur - ther confirmed by weaving practice. 展开更多
关键词 FRICTION SPUN CORE YARN anti - STRIPPING PROPERTY STRIPPING resistance testing.
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防渗墙塑性混凝土力学性能-波速拟合曲线研究
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作者 陈建国 黄凯 +3 位作者 梁巍耀 叶兆青 黄卓杰 黄小兵 《新型建筑材料》 2024年第7期108-112,共5页
针对塑性混凝土防渗墙超声波无损检测的应用进行研究。首先设计了3个强度等级的掺膨润土塑性混凝土,通过正交试验探究膨润土掺量、水胶比、砂率、外加剂掺量对塑性混凝土工作性能的影响,确定了最终配合比。基于最终配合比制备混凝土试... 针对塑性混凝土防渗墙超声波无损检测的应用进行研究。首先设计了3个强度等级的掺膨润土塑性混凝土,通过正交试验探究膨润土掺量、水胶比、砂率、外加剂掺量对塑性混凝土工作性能的影响,确定了最终配合比。基于最终配合比制备混凝土试件并进行力学性能试验、超声波测试和超声波测试比对试验,将得到的强度-波速关系和弹性模量-波速关系进行函数拟合,建立力学性能-波速曲线。结果表明,拟合曲线主要符合二次函数和幂函数形式,得到的5~7 MPa强度-波速曲线(二次函数)和1~7 MPa弹性模量-波速曲线(二次函数)的拟合程度较好,相关系数R2均大于0.94。 展开更多
关键词 塑性混凝土 防渗墙 超声波检测 膨润土 力学性能-波速曲线
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少筋钢筋混凝土桥墩M-φ曲线的计算 被引量:8
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作者 鞠彦忠 阎贵平 +1 位作者 张杰 王显利 《中国安全科学学报》 CAS CSCD 2003年第10期63-65,共3页
应用有限条法 ,对圆端形桥墩正截面弯矩 -曲率 (M φ)关系曲线进行计算。计算中针对桥墩截面低配筋率情况考虑了混凝土抗压强度计算、抗拉强度计算及钢筋的弹性段、屈服平台段和强化段计算。应用MATLAB编写了计算程序 ,并分析了受拉区... 应用有限条法 ,对圆端形桥墩正截面弯矩 -曲率 (M φ)关系曲线进行计算。计算中针对桥墩截面低配筋率情况考虑了混凝土抗压强度计算、抗拉强度计算及钢筋的弹性段、屈服平台段和强化段计算。应用MATLAB编写了计算程序 ,并分析了受拉区混凝土抗拉强度对低配筋率钢筋混凝土桥墩M φ曲线的影响。最后用理论M φ骨架曲线验推得位移 -内力曲线与试验实测数据对比 ,证实了理论M φ曲线计算的正确性。 展开更多
关键词 圆端形桥墩 钢筋混凝土 M-Φ曲线 抗震
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7家血站实验室抗-HCV ELISA试验临界值评价 被引量:7
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作者 刘正敏 王瑞 +12 位作者 黄力勤 胡京辉 常乐 甄伟 王鹏 王芳 魏超 朱绍汶 曾劲峰 释艳华 郑伟 王露楠 葛红卫 《中国实验血液学杂志》 CAS CSCD 北大核心 2019年第1期253-259,共7页
目的:评价7家血站实验室抗-HCV ELISA实验灰区的必要性及适宜性。方法:7家血站实验室编码为1,2,3,4,5,6和7,而8种ELISA试剂分别编码为A,B,C,D,E,F,G和H。7家血站实验室使用8种不同厂商ELISA试剂中的1种或2种对同一组(n=1259)标本进行抗-... 目的:评价7家血站实验室抗-HCV ELISA实验灰区的必要性及适宜性。方法:7家血站实验室编码为1,2,3,4,5,6和7,而8种ELISA试剂分别编码为A,B,C,D,E,F,G和H。7家血站实验室使用8种不同厂商ELISA试剂中的1种或2种对同一组(n=1259)标本进行抗-HCV检测。对检测结果有差异的标本进行Western blot补充试验以明确标本血清学状态。统计各实验室真阳性检出率、灰区标本确证阳性率以分析7家血站实验室抗-HCV试验"灰区"设置的必要性。通过绘制ROC曲线确定7家血站实验室抗-HCV ELISA试验的最佳临界值,比较3种不同临界值(实验室工作临界值、厂商推荐临界值、最佳临界值)下灵敏度及特异性的变化以分析7家血站实验室抗-HCV ELISA试验"灰区"的合理性。结果:7家血站实验室(其中编码1号实验室采用了A、B两种试剂)真阳性检出率分别是95.40%(1A)、99.23%(1B)、94.25%(2C)、96.17%(3D)、98.08%(4E)、96.93%(5F)、97.32%(6G因为有1家血站使用了两种ELISA试剂)、93.10%(7H)。除2C(94.25%)、7H(93.10%)外其余均大于95%。设立灰区的6家血站实验室(1A、1B、3D、4E、5F、6G和7H)灰区确证阳性率分别为0.00%、0.00%、21.43%、0.00%、0.00%、0.00%、38.89%。绘制ROC曲线比较3种不同临界值关系显示,5家实验室(1B、2C、4E、5F、6G)抗-HCV最佳临界值>厂商推荐临界值>实验室工作临界值,使用厂商推荐的临界值已可以达到筛查实验室高灵敏的要求; 1A、3D、7H抗-HCV最佳临界值<厂商推荐临界值,考虑使用适宜的灰区。设立灰区的6家实验室,使用实验室,工作临界值与使用厂商推荐临界值相比,仅3D、7H灵敏度略有提高(分别为1.60%、2.70%),其余实验室灵敏度无变化且特异性下降(0.20%-0.50%)。结论:除1A、3D、7H可适当设置灰区外,研究结果支持其他实验室抗-HCV ELISA试验取消灰区;即使是同一实验室也要对灰区设置进行科学评估,不宜盲目使用同一尺度,应建立适宜的判定策略。 展开更多
关键词 ROC曲线 -HCV 血站实验室 灰区 酶联免疫吸附试验
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