期刊文献+
共找到13篇文章
< 1 >
每页显示 20 50 100
世茂国际广场主楼与裙房减振弱连接设计 被引量:7
1
作者 汪大绥 张坚 《建筑结构》 CSCD 北大核心 2007年第5期17-19,37,共4页
利用耗能减振技术连接不同高度、不同质量、不同刚度的主楼与裙房,在国内尚无工程实践。世茂国际广场裙房结构刚度中心与质量中心存在严重的偏心,设计采用40个粘滞流体阻尼器将其与主楼连成整体。通过结构整体弹塑性分析,表明连接解决... 利用耗能减振技术连接不同高度、不同质量、不同刚度的主楼与裙房,在国内尚无工程实践。世茂国际广场裙房结构刚度中心与质量中心存在严重的偏心,设计采用40个粘滞流体阻尼器将其与主楼连成整体。通过结构整体弹塑性分析,表明连接解决了裙房的偏心问题,而且粘滞流体阻尼器能够实现结构各阶段的抗震目标,在风荷载作用下它也能起到连杆及部分耗能的作用。 展开更多
关键词 高层建筑 裙房 抗震设计 粘滞流体阻尼器 连接
下载PDF
弱碱复合驱用石油羧酸盐研制及其性能评价 被引量:2
2
作者 徐艳姝 《大庆石油地质与开发》 CAS CSCD 北大核心 2013年第6期108-111,共4页
以大庆减压馏分油为原料,采用新型复合催化剂和氧化磺化联合新工艺,合成了弱碱石油羧酸盐小试产品,并对其进行界面活性、稳定性、吸附及驱油效果等项性能的评价。研究结果表明:石油羧酸盐小试产品可在较宽的表面活性剂质量浓度和Na... 以大庆减压馏分油为原料,采用新型复合催化剂和氧化磺化联合新工艺,合成了弱碱石油羧酸盐小试产品,并对其进行界面活性、稳定性、吸附及驱油效果等项性能的评价。研究结果表明:石油羧酸盐小试产品可在较宽的表面活性剂质量浓度和Na2CO,质量浓度区间内与大庆原油形成10-3mN/m数量级的超低界面张力,其复合体系具有较好的界面张力、黏度稳定性和抗吸附性能;室内天然岩心平均驱油效率比水驱提高17.13%。 展开更多
关键词 弱减 石油羧酸盐 研制 性能
下载PDF
弱约束性碳减排政策的碳回弹效应研究——基于低碳城市建设的准自然实验
3
作者 宋依纯 朱于珂 高红贵 《软科学》 CSSCI 北大核心 2024年第8期121-128,144,共9页
通过构建弱约束性碳减排政策对城市碳回弹效应的理论与实证研究框架,考察低碳城市建设扩大城市碳回弹效应的形成机制,挖掘低碳城市建设抑制城市碳回弹效应的作用路径。研究发现:(1)总体而言,低碳城市建设将提升能源使用效率,通过“替代... 通过构建弱约束性碳减排政策对城市碳回弹效应的理论与实证研究框架,考察低碳城市建设扩大城市碳回弹效应的形成机制,挖掘低碳城市建设抑制城市碳回弹效应的作用路径。研究发现:(1)总体而言,低碳城市建设将提升能源使用效率,通过“替代效应”与“收入效应”扩大城市碳回弹效应,同时也将带动地区经济增长,通过“产出效应”扩大城市碳回弹效应;(2)低碳城市建设可以通过促进低碳技术创新,降低煤炭消费比重,进而抑制城市碳回弹效应,其中通过低碳技术创新产生的抑制效果更为突出;(3)低碳城市建设将通过公众参与型工具与市场激励型工具有效抑制城市碳回弹效应,其中公众参与型工具的抑制效果要优于市场激励型工具。 展开更多
关键词 约束性碳排政策 低碳城市建设 碳回弹效应 多期DID模型 抑制路径
原文传递
语言的淡化方式研究 被引量:1
4
作者 杨华堂 张兰 《兰州文理学院学报(社会科学版)》 2017年第3期106-109,共4页
语言的淡化是为了把某些严重的事说得很轻松,将不好听的话说得不那么难听。与弱化、缓和语、低调陈述有相同之处,也有不同之处。它是通过掩盖、弱减语意达到礼貌、安抚、宽慰等目的。它常用的方法有使用数量词、吞吞吐吐的语言、意义不... 语言的淡化是为了把某些严重的事说得很轻松,将不好听的话说得不那么难听。与弱化、缓和语、低调陈述有相同之处,也有不同之处。它是通过掩盖、弱减语意达到礼貌、安抚、宽慰等目的。它常用的方法有使用数量词、吞吞吐吐的语言、意义不太高雅的词、解释等。 展开更多
关键词 淡化 掩盖 弱减
下载PDF
Causes and Countermeasures for Fragrance Diminishing of Rice Cultivar Daohuaxiang 2 in Heilongjiang Province 被引量:1
5
作者 于清涛 李赞 刘乃新 《Agricultural Science & Technology》 CAS 2016年第10期2293-2296,共4页
High-quality fragrant rice Daohuaxiang 2 is a well-known variety in grain industry of Heilongjiang Province. However, its fragrance has weakened in recent years. In this paper, the causes for fragrance diminishing of ... High-quality fragrant rice Daohuaxiang 2 is a well-known variety in grain industry of Heilongjiang Province. However, its fragrance has weakened in recent years. In this paper, the causes for fragrance diminishing of Daohuaxiang 2 were discussed in depth. It was pointed out that variety degeneration, growth period influence, environmental factor influence, soil fertility influence and long drying time were the main causes for fragrance diminishing of Daohuaxiang 2. In addition, countermeasures for avoiding the fragrance diminishing were put forward. 展开更多
关键词 Daohuaxiang 2 FRAGRANCE Diminishing COUNTERMEASURES
下载PDF
“E、I”三段论推理体系
6
作者 朱玉堦 周光明 《渝州大学学报(哲学社会科学版)》 1993年第1期79-86,共8页
本文提出了一种新的推理体系,即“E、I”三段论推理体系。它根据二分思想、双向思维,甩“E”、“I”命题形式表达直言命题,用类似算术中的加减法公式进行推演,所推得的有效式较传统三段论多。
关键词 “E I”三段论 同现 补联 同联 弱减
下载PDF
Robustness analysis for a class of nonlinear descriptor systems 被引量:1
7
作者 吴敏 张凌波 何勇 《Journal of Central South University of Technology》 2004年第4期457-460,共4页
The robustness analysis problem of a class of nonlinear descriptor systems is studied. Nonlinear matrix inequality which has the good computation property of convex feasibility is employed to derive some sufficient co... The robustness analysis problem of a class of nonlinear descriptor systems is studied. Nonlinear matrix inequality which has the good computation property of convex feasibility is employed to derive some sufficient conditions to guarantee that the nonlinear descriptor systems have robust disturbance attenuation performance, which (avoids) the computational difficulties in conversing nonlinear matrix and Hamilton-Jacobi inequality. The computation property of convex feasibility of nonlinear matrix inequality makes it possible to apply the results of nonlinear robust control to practice. 展开更多
关键词 nonlinear descriptor system robustness analysis robust disturbance attenuation nonlinear matrix (inequality)
下载PDF
Non-Newtionian Effects on Chaotic Mixing Between Eccentric Cylinders 被引量:1
8
作者 范毓润 卢著敏 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第3期306-309,共4页
Effect of fluid elasticity and shear-thinning viscosity on the chaotic mixing between two alternately rotating cylinders has been studied. The h-p finite element method is used to obtain high accurate solutions of the... Effect of fluid elasticity and shear-thinning viscosity on the chaotic mixing between two alternately rotating cylinders has been studied. The h-p finite element method is used to obtain high accurate solutions of the steady flow. The unsteady, periodic flow is simulated using the piecewise-steady approximation. Characteristics of the chaotic mixing are analyzed by examining the asymptotic coverage of a passive tracer and the lineal stretching of the fluid elements in the annulus. For the viscoelastic fluids modeled by the upper-convected Maxwell constitutive equation (UCM), our computation predicts little effect of the fluid elasticity on the mixing patterns. On the other hand, the shear-thinning viscosity, modeled by the Carreau equation, has a large impact on the advection of a passive tracer and the distribution of lineal stretching. We find that the zones of the lowest stretching match remarkably well with the regular zones in the tracer-coverage plotting. Our study reveals the vital importance of reducing the discretization errors of the velocity field in the numerical simulation of chaotic flews. 展开更多
关键词 chaotic mixing VISCOELASTICITY shear-thinning viscosity
下载PDF
Exact Solutions of a Coupled Burgers System
9
作者 HUANG Ling 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5期781-784,共4页
The exact solutions of a new coupled Burgers system are studied in three different ways. The first type of solutions are found thanks to the coupled Burgers system possessing a simple single Burgers reduction. The sec... The exact solutions of a new coupled Burgers system are studied in three different ways. The first type of solutions are found thanks to the coupled Burgers system possessing a simple single Burgers reduction. The second type of multiple soliton solutions are revealed via the decouple procedure. The third type of exact solutions are found by means of a prior ansatz and solutions of the heat conduction equation. Two different kinds of soliton fission phenomena of the model are discovered and a special type of completely elastic soliton collision without phase shift of the model is also displayed. 展开更多
关键词 exact solutions SOLITONS coupled Burgers equations
下载PDF
Influence of DSP controller on performance of a permanent magnet brushless AC drive in flux-weakening mode
10
作者 HOWE D. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第2期83-89,共7页
The flux-weakening performance of a permanent magnet brushless AC drive was investigated using both floating-point and fixed-point DSP controllers. A significant current oscillation was observed when the drive was ope... The flux-weakening performance of a permanent magnet brushless AC drive was investigated using both floating-point and fixed-point DSP controllers. A significant current oscillation was observed when the drive was operated at high-speed in the flux-weakening mode with the fixed-point DSP. The investigation showed that this was due to the on-line compensation of the winding resistance voltage drop and quantisation errors associated with the fixed-point architecture of the DSP. A simple look-up table scheme is proposed to eliminate the oscillation and to achieve extended flux-weakening capability. 展开更多
关键词 Brushless drive DSP Electrical machine FLUX-WEAKENING OSCILLATION QUANTISATION
下载PDF
气候变化经济学能解决气候变化问题吗——对西方气候变化模型及方法的批判性反思
11
作者 贾点点 《当代经济研究》 CSSCI 北大核心 2024年第6期70-78,共9页
气候变化经济学是新古典经济学在气候变化领域的分支。它运用外部性内部化方法,将气候变化影响纳入长期经济增长动态模型,由此得到“最优”的经济增长与气候变化路径。然而,最优解中的全球升温路径显著高于《巴黎协定》目标,为主要发达... 气候变化经济学是新古典经济学在气候变化领域的分支。它运用外部性内部化方法,将气候变化影响纳入长期经济增长动态模型,由此得到“最优”的经济增长与气候变化路径。然而,最优解中的全球升温路径显著高于《巴黎协定》目标,为主要发达国家的弱减排政策提供了所谓的理论支持。这一模型结果的生成并非基于数学模型的“科学性”,而是基于模型与参数的设定偏好,这些设定与偏好反映出气候变化经济学的新古典缺陷,即成本—效益分析下的机械论思维和外部性内部化方法的局限。解决气候变化问题,应从人与自然的物质变换关系出发,设置全面的气候变化控制目标和实施方案,建设人类命运共同体,形成全球气候治理最广泛的共同力量。 展开更多
关键词 气候变化 诺德豪斯 外部性内部化 弱减排政策 人类命运共同体
原文传递
THE ROLES OF DETOXIFYING ENZYMES AND AChE INSENSITIVITY IN METHAMIDOPHOS RESISTANCE DEVELOPMENT AND DECLINE IN NILAPARVATA LUGENS 被引量:5
12
作者 Ze-wenLiu Zhao-junHan Ling-chunZhang 《Entomologia Sinica》 CSCD 2003年第3期179-184,共6页
Methamidophos resistance of brown planthopper ( Nilaparvata lugens Stl, BPH) was selected in laboratory. After successive selection for 9 generations, the selection was ceased by rearing BPH without contact with an... Methamidophos resistance of brown planthopper ( Nilaparvata lugens Stl, BPH) was selected in laboratory. After successive selection for 9 generations, the selection was ceased by rearing BPH without contact with any insecticide for 9 generations. In the full course, the successive changes of esterase activity, MFO activity, GSTs activity and AChE insensitivity were analyzed. The results showed that the change of esterase activity was high correlated with that of methamidophos in the full course, which indicated that esterase played very important role both in the resistance development and in the resistance decline. However, the change of AChE insensitivity only significantly correlated with that of resistance in the development stage, and the change of MFO activity or GSTs activity only significantly correlated with that of the resistance in the decline stage, which indicated the changes of AChE insensitivity, MFO activity or GSTs activity only played some roles in different stages of the resistance change. 展开更多
关键词 detoxifying enzyme AChE insensitivity resistance development resistance decline
原文传递
Interventions to improve physical function and prevent adverse events in cirrhosis 被引量:2
13
作者 Hirsh D.Trivedi Elliot B.Tapper 《Gastroenterology Report》 SCIE EI 2018年第1期13-20,I0001,共9页
Cirrhosis is associated with debilitating complications that significantly impact on a patient’s physical function and reduce quality of life.Owing to highly prevalent sarcopenia,malnutrition and hepatic encephalopat... Cirrhosis is associated with debilitating complications that significantly impact on a patient’s physical function and reduce quality of life.Owing to highly prevalent sarcopenia,malnutrition and hepatic encephalopathy,functional impairment or frailty is a common complication of cirrhosis.Frailty in turn increases the patient’s risk of hospitalization,accidental falls and fractures,and death.The management of frailty and its associated adverse effects is imperative in improving the overall prognosis of patients with advanced liver disease.The cornerstone of therapy revolves around optimizing physical function with appropriate nutrition and exercise.Nutritional therapy with protein supplementation has shown significant benefit,while studies on exercise have been controversial.However,newly emerging studies trend towards a beneficial effect of physical exercise with improvement in quality of life.The implementation of technology in liver disease management shows future promise.Fitbits and other wearable devices can be used to help monitor a patient’s personal progress in physical exercise and nutritional optimization.Additionally,the progressive development of new smartphone applications to help aid in the diagnosis and monitoring of complications of cirrhosis provides a sophisticated avenue for improving care of patients with cirrhosis. 展开更多
关键词 Hepatic encephalopathy FRAILTY SARCOPENIA MALNUTRITION liver disease
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部