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线型缩聚中当量系数的新定义及其应用 被引量:7
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作者 郭霖 《高分子通报》 CAS CSCD 1996年第4期252-255,共4页
本文介绍了线型缩聚计算中广泛成立的当量系数γ的新定义及其应用。
关键词 线型缩聚 数均聚合度 当量系 缩聚
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上海市公路车辆超载情况调查 被引量:3
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作者 彭波 毛如麟 钱钟达 《上海公路》 1999年第1期26-30,共5页
针对近年来货运车辆荷载级位和数量的增长加速了对公路设施的损坏现象,本课题在全市范围内选择了十五条具有代表性的干线公路,进行中型以上货车的轴荷载称重及装载率调查,得出货运车辆的超载超限规律,并分析了超限轴载造成的额外损耗,... 针对近年来货运车辆荷载级位和数量的增长加速了对公路设施的损坏现象,本课题在全市范围内选择了十五条具有代表性的干线公路,进行中型以上货车的轴荷载称重及装载率调查,得出货运车辆的超载超限规律,并分析了超限轴载造成的额外损耗,为下一步制定超重车管理政策提供了事实依据。 展开更多
关键词 超载 超限 当量标准轴 疲劳损耗 调查分析 公路运输 货物运输车辆
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Advantages of Maize-Legume Intercropping Systems 被引量:3
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作者 Shyamal Kheroar Bikas Chandra Patra 《Journal of Agricultural Science and Technology(B)》 2013年第10期733-744,共12页
An experiment was conducted during Kharif seasons of 2009 and 2010 on sandy loam soil of West Bengal, India to evaluate the productivity and economic viability of maize + legume intercropping systems in additive as w... An experiment was conducted during Kharif seasons of 2009 and 2010 on sandy loam soil of West Bengal, India to evaluate the productivity and economic viability of maize + legume intercropping systems in additive as well as in replacement series with different row proportions. Maize (Zea rnays L.) cv. "Vijay" (composite), green gram (Vigna radiata L.) cv. "Samrat", black gram (Vigna mungo L.) cv. "Sarada", soybean (Glycine max L. Merril) cv. "PK 327" and peanut (Arachis hypogaea L.) cv. "JL 24", were tested in monoculture as well as in intercropping situations with 1:1 (additive series) and 1:2 ratios (replacement series). The result indicated that intercropped legumes improved the yield components of maize and offered some bonus yield. The highest maize grain yield (2,916.28 kg/ha) and maize equivalent yield (4,831.45 kg/ha) were recorded with maize + green gram (1:1) and maize + peanut (1:I), respectively. The values of all the competition functions were always greater than unity and maize + black gram (1:2) recorded the highest values of land equivalent ratio (1.433), area time equivalent ratio (1.374) and land equivalent coefficient (0.421). Maximum monetary advantage (Rs. 10,579.13) was found with maize + green gam (l:1). Maize + peanut (1:2) combination recorded the highest relative net return (2.01), net return (Rs. 28,523.08), benefit-cost ratio (2.76) ad per day return (Rs. 259.30). 展开更多
关键词 Maize (Zea mays L.) INTERCROPPING LEGUME monetary advantage land equivalent ratio area time equivalent ratio relative net return benefit-cost ratio.
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Designing of Quasi-universal Compensator for Testing Aspherical Surface 被引量:1
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作者 WANGWensheng XUBin 《Semiconductor Photonics and Technology》 CAS 1998年第1期40-44,61,共6页
According to the theory of testing aspherical surface by normal aberration compensation method,the designing method of quasi-universal compensator is studied.On the basis of third-order aberration theory,after calcula... According to the theory of testing aspherical surface by normal aberration compensation method,the designing method of quasi-universal compensator is studied.On the basis of third-order aberration theory,after calculating and optimizing with an optical design program,the structure parameters of a compensator are obtained.This new compensator could be used in Twyman-Green interferometer,and in measurement of a certain range of paraboloid ellipsoid and hyperboloid.The compensation accuracy is more than 0.02 λ . 展开更多
关键词 Aspherical Surface Normal Aberration Compensation Method Quasi-universal Compensator
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Simulation and Optimization Design Based on Adams Engine Mounting System 被引量:1
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作者 Xie Jianxin Wang Xiaole Liu Chao 《International Journal of Technology Management》 2014年第7期152-154,共3页
The content of this subject research is to conduct optimization for engine mounting system, and through optimization, it can make the vibration between engine and vehicle body achieve a minimum, using Adams software f... The content of this subject research is to conduct optimization for engine mounting system, and through optimization, it can make the vibration between engine and vehicle body achieve a minimum, using Adams software for simulation. It studies the isolation vibration of the engine mounting system and conducts goal optimization for fixed frequency. This paper uses two methods for optimization. One is to use the rational allocation of fixed frequency to optimize the fixed frequency, and the other is to use energy decoupling method to optimize the fixed frequency. It uses Adams software for simulation of the optimized fixed frequency and conducts comparison of simulated results. The simulated results show that the optimized energy distribution situation almost achieves 90%. Compared with original data, decoupling degree also has a very great improvement, illustrating that the optimized data has greater effect for the isolated vibration of engine, in order to further verify the feasibility of optimization design method. 展开更多
关键词 engine mounting system optimization design SIMULATION ADAMS
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Discussion of Influences on Snow Water Equivalent at Utah Snow Courses
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作者 Randall P. Julander Jordan A. Clayton 《Journal of Earth Science and Engineering》 2015年第3期147-172,共26页
Snow data collection systems in the western United States were originally designed to forecast water supply and may be subject to several sources of bias. In addition to climate change and weather modification effects... Snow data collection systems in the western United States were originally designed to forecast water supply and may be subject to several sources of bias. In addition to climate change and weather modification effects, site-specific effects may be introduced from vegetation changes, site physical changes, measurement technique, and sensor changes. This paper examines changes in Utah's snowpack conditions over the past decade compared with all previous measurement years, focusing on the 15 snow courses with the longest observational record within the state of Utah. Although patterns in snowpack data consistent with those that would be expected due to temperature h as greater declines at lower elevations and latitudes--were not identified, snow water equivalent decreased at sites with significant increases in vegetation coverage. Additionally, we provide a list of 22 snow courses in Utah that are best-suited for long-term climate analysis. 展开更多
关键词 Snow water equivalent UTAH snow course VEGETATION changes over time.
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Analysis of the Power System from an Electron Beam Accelerator and the Correlation with the Theoretical Dosimetry for Radiation Processing
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作者 Samir Luiz Somessari Elizabeth S. Ribeiro Somessari Carlos Gaia da Silveira Wilson Aparecido Parejo Calvo 《Journal of Physical Science and Application》 2015年第5期356-366,共11页
Dynamitron DC1500/25/04 type EBA (Electron beam accelerator), model JOB 188, was manufactured by IBA Industrial (Radiation Dynamics, Inc.) and installed at IPEN-CNEN/SP, in 1978. The technical specifications of th... Dynamitron DC1500/25/04 type EBA (Electron beam accelerator), model JOB 188, was manufactured by IBA Industrial (Radiation Dynamics, Inc.) and installed at IPEN-CNEN/SP, in 1978. The technical specifications of the EBA are: energy 0.5 to 1.5 MeV; beam current: 0.3 to 25.0 mA; beam scanning: 60 to 120 cm; beam width: 25.4 mm and frequency: 100 Hz. Nowadays, this accelerator has been used for innumerable applications, such as: For sterilization of medical, pharmaceutical and biological products, treatment of industrial and domestic effluents and sludge, preservation and disinfestations of foods and agricultural products. Other important application are lignocellulosic material irradiation as a pre-treatment to produce ethanol bio-fuel, decontamination of pesticide packing, solid residues remediation, organic compounds removal from wastewater, treatment of effluent from petroleum production units, crosslinking of foams, wires and electric cables. Electron accelerator JOB 188 is, also, very important composite and nanocomposite materials and carbon fibers irradiation, irradiated grafting ion-exchange membranes for fuel cells application, natural polymers and multilayer packages irradiation and biodegradable blends production. The energy of the electron beam is calculated as a function of the current in the accelerator high-voltage divisor, taking into account the thickness and density of the material to be irradiated. This energy is calculated considering the electron through the entire material and the distance from the titanium foil window, so that the absorbed doses at the points of entrance and exit are equivalent on the material. The dose is directly proportional to the beam current and the exposure time of the material under the electron beam and inversely proportional to the scan width. The aim of this paper is to analyze the power system parameters of the EBA Dynamitron DC 1500/25/04, such as, voltage and RMS (Root-mean-square) current in the oscillator system, high voltage generator and waveform. For this purpose software developed in the Radiation Technology Center at IPEN/CNEN-SP to simulate the energy efficiency of this industrial accelerator. Finally, it is also targeted to compare theoretical dosimetry using parameters of energy and beam current with data from the accelerator power system. This knowledge and technology will be very useful and essential for the control system upgrade of EBA, mainly Dynamitron DC 1500/25/04 taking into consideration that radiation processing technology for industrial and environmental applications has been developed and used worldwide. 展开更多
关键词 Electron beam accelerator industrial dosimetry radiation processing accelerator power system Dynamitron DC 1500/25/04 accelerator.
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Applying Value Transfer Method for Eco-Service Valuation in China 被引量:31
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作者 谢高地 甄霖 +2 位作者 鲁春霞 肖玉 李文华 《Journal of Resources and Ecology》 CSCD 2010年第1期51-59,共9页
国内和国外生态系统服务物理量和价值量的评估都难以得出让公众和学术界普遍接受的结果,这反映了该领域研究方法还不成熟,需要继续完善。如何建立符合中国基本国情的单位价值量是核算生态系统服务功能价值的核心。由于中国缺乏完善的市... 国内和国外生态系统服务物理量和价值量的评估都难以得出让公众和学术界普遍接受的结果,这反映了该领域研究方法还不成熟,需要继续完善。如何建立符合中国基本国情的单位价值量是核算生态系统服务功能价值的核心。由于中国缺乏完善的市场环境,如何选择一个合理的价格体系作为衡量生态系统服务的单位价值量仍然还是一个难题。目前普遍采用的市场价格很难真实反映消费者剩余,从而导致单位价值或者说最终价值评估结果的不准确。本研究将生态服务划分为食物生产、原材料生产、景观愉悦、气体调节、气候调节、水源涵养、土壤形成与保持、废物处理、生物多样性维持共9项,就森林、草地、农田、湿地、水体和荒漠6类生态系统的9项生态系统服务价值相对生态重要性进行了问卷调查,进而形成中国生态系统单位面积生态服务价值评估单价体系,通过结果对比发现,该生态系统服务单价体系与基于物质量估算的生态系统服务价值之间具有较好的可比性,可较准确地反映中国各项生态系统服务的相对重要性,在没有其他更为可靠的方法的情况下,可以采用该方法对中国生态系统服务价值进行评估,可以作为适合中国生态系统状况和经济发展水平的一个生态系统服务价值评估工具。对上述方法的合理性我们也做了一个问卷调查,约70%的被调查者认为这是一个"比较合理"的评估方法,约20%的被调查者认为并不合理,可以肯定在生态系统服务价值评估技术取得更新的一些研究成果之前,这种对生态系统服务价值进行评估的方法将长期存在争论。本方法仍有许多需要改进和完善之处,如生态系统服务价值的空间异质性和时间动态性有待考虑,具体应用时可采用生态服务价值生物量调整因子来做进一步修订。 展开更多
关键词 ecosystem service unit value MODIFICATION SURVEY China
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Topography of spinal column and kidney receptors as illustrated by microsystem of the foot
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作者 Tadeusz Kasperczyk Robert Walaszek 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2015年第3期329-334,共6页
OBJECTIVE:To test the accuracy of the distribution of reflective zones on the feet as proposed by William Fitzgerald using the spine and kidney receptors as reference points.METHODS:Spine and feet lengths were measure... OBJECTIVE:To test the accuracy of the distribution of reflective zones on the feet as proposed by William Fitzgerald using the spine and kidney receptors as reference points.METHODS:Spine and feet lengths were measured first along straight lines and then again,taking into consideration the anatomical curves.The spinal column was further measured with regard to its individual regions(cervical,thoracic,lumbar,sacrum-coccyx).Straight-line measurements were taken with the help of an anthropometer.Measurements that took into account all of the curves were performed with the opisometer(also known as a "map measurer").All the measurements were accurate to within 1 mm.The study subjects were a healthy,physically fit 16-year-old female student and a 53-year-old male office employee exposed to an average dose of physical exercise.RESULTS:The kidney receptor in the foot did not reflect onto the predetermined lumbar section of the spinal column as measured along the straight line or with regard to curves.Instead,in both subjects the kidney receptor reflected onto the thoracic spine.CONCLUSION:Te particular level of the spinal cord that innervates the given organ controls the distribution of receptors of individual organs in the foot. 展开更多
关键词 REFLEXOTHERAPY Microsystem of the foot Reflective zones
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Virial Coefficients from Unified Statistical Thermodynamics of Quantum Gases Trapped under Generic Power Law Potential in d Dimension and Equivalence of Quantum Gases
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作者 Shah Mohammad Bahauddin Mir Mehedi Faruk 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第9期291-296,共6页
From the unified statistical thermodynamics of quantum gases, the virial coefficients of ideal Bose and Fermi gases, trapped under generic power law potential are derived systematically. From the general result of vir... From the unified statistical thermodynamics of quantum gases, the virial coefficients of ideal Bose and Fermi gases, trapped under generic power law potential are derived systematically. From the general result of virial coefficients, one can produce the known results in d = 3 and d = 2. But more importantly we found that, the virial coefficients of Bose and Fermi gases become identical(except the second virial coefficient, where the sign is different)when the gases are trapped under harmonic potential in d = 1. This result suggests the equivalence between Bose and Fermi gases established in d = 1(J. Stat. Phys. DOI 10.1007/s10955-015-1344-4). Also, it is found that the virial coefficients of two-dimensional free Bose(Fermi) gas are equal to the virial coefficients of one-dimensional harmonically trapped Bose(Fermi) gas. 展开更多
关键词 virial coefficients quantum gas EQUIVALENCE
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