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能量守恒科学 被引量:1
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作者 付昱华 《德州学院学报》 2004年第6期20-24,共5页
在能量守恒科学中,占统治与主导地位的是能量守恒定律.其他的定律,或者可由能量守恒定律导出,或者必须经受能量守恒定律的检验,或者是错误的.主要讨论四个问题:根据能量守恒定律重新考虑力与质量、速度的关系;重新导出其他定律,如万有... 在能量守恒科学中,占统治与主导地位的是能量守恒定律.其他的定律,或者可由能量守恒定律导出,或者必须经受能量守恒定律的检验,或者是错误的.主要讨论四个问题:根据能量守恒定律重新考虑力与质量、速度的关系;重新导出其他定律,如万有引力定律、库仑定律等;检验其他定律是否可以应用,给出动量守恒定律和动量矩守恒定律不成立(其结果与能量守恒定律相矛盾)的实例;将旧的学科改造成为新的学科,例如将牛顿力学改造为新牛顿力学,新牛顿力学可以部分取代相对论并解决相对论无法解决的问题. 展开更多
关键词 能量守恒 能量守恒定律 能量守恒科学 新牛顿力学
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基于科学史和系统论的“生态系统的能量流动”教学设计
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作者 朱靖 《中学生物学》 2020年第7期7-9,共3页
在“生态系统的能量流动”一节的教学中,以真实情境展开讨论,探讨生态系统研究的意义和方法,提升学生社会责任意识;充分运用科学史素材渗透系统论的思想和方法,使学生亲历林德曼的思维过程和探究历程,从定性和定量两个角度建构生态系统... 在“生态系统的能量流动”一节的教学中,以真实情境展开讨论,探讨生态系统研究的意义和方法,提升学生社会责任意识;充分运用科学史素材渗透系统论的思想和方法,使学生亲历林德曼的思维过程和探究历程,从定性和定量两个角度建构生态系统能量流动模型,促进学生理解科学本质,感悟科学精神,培养科学思维和科学探究能力。 展开更多
关键词 能量流动科学史系统论 教学设计
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调养型美体内衣上市
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《中国科学美容》 2004年第2期90-90,共1页
关键词 调养型美体内衣 功效 深圳紫迪欣实业有限公司 日本宇宙能量开发研究所 能量科学
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Search by shortcuts in P2P scientific collaboration system
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作者 Deng Qianni(邓倩妮) Chen Li +1 位作者 Lu Xinda Li Minglu 《High Technology Letters》 EI CAS 2005年第3期298-300,共3页
A P2P scientific collaboration is a P2P network whose members can share documents, co-compile papers and codes, and communicate with each other instantly. From the simulation experiment we found that P2P collaboration... A P2P scientific collaboration is a P2P network whose members can share documents, co-compile papers and codes, and communicate with each other instantly. From the simulation experiment we found that P2P collaboration system is a power-law network with a tail between -2 and -3.We utilized the algorithm that searches by high-degree shortcuts to improve the scalability of p2p collaboration system. The experimental result shows that the algorithm works better than random walk algorithm. 展开更多
关键词 power-law distribution P2P scientific collaboration high-degree shortcut random walk
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A meta-analysis of the effects of energy intake on risk of digestive cancers 被引量:1
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作者 Xiao-Feng Yu Yi-Qian Wang +1 位作者 Jian Zou Jie Dong 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第48期7362-7370,共9页
AIM:To quantitatively assess the relationship between energy intake and the incidence of digestive cancers in a meta-analysis of cohort studies.METHODS:We searched MEDLINE,EMBASE,Science Citation Index Expanded,and th... AIM:To quantitatively assess the relationship between energy intake and the incidence of digestive cancers in a meta-analysis of cohort studies.METHODS:We searched MEDLINE,EMBASE,Science Citation Index Expanded,and the bibliographies of retrieved articles.Studies were included if they reported relative risks(RRs) and corresponding 95% CIs of digestive cancers with respect to total energy intake.When RRs were not available in the published article,they were computed from the exposure distributions.Data were extracted independently by two investigators and discrepancies were resolved by discussion with a third investigator.We performed fixed-effects meta-analyses and meta-regressions to compute the summary RR for highest versus lowest category of energy intake and for per unit energy intake and digestive cancer incidence by giving each study-specific RR a weight that was proportional to its precision.RESULTS:Nineteen studies consisting of 13 independent cohorts met the inclusion criteria.The studiesincluded 995 577 participants and 5620 incident cases of digestive cancer with an average follow-up of 11.1 years.A significant inverse association was observed between energy intake and the incidence of digestive cancers.The RR of digestive cancers for the highest compared to the lowest caloric intake category was 0.90(95% CI 0.81-0.98,P < 0.05).The RR for an increment of 239 kcal/d energy intake was 0.97(95% CI 0.95-0.99,P < 0.05) in the fixed model.In subgroup analyses,we noted that energy intake was associated with a reduced risk of colorectal cancer(RR 0.90,95% CI 0.81-0.99,P < 0.05) and an increased risk of gastric cancer(RR 1.19,95% CI 1.08-1.31,P < 0.01).There appeared to be no association with esophageal(RR 0.96,95% CI 0.86-1.07,P > 0.05) or pancreatic(RR 0.79,95% CI 0.49-1.09,P > 0.05) cancer.Associations were also similar in studies from North America and Europe.The RR was 1.02(95% CI 0.79-1.25,P > 0.05) when considering the six studies conducted in North America and 0.87(95% CI 0.77-0.98,P < 0.05) for the five studies from Europe.CONCLUSION:Our findings suggest that high energy intake may reduce the total digestive cancer incidence and has a preventive effect on colorectal cancer. 展开更多
关键词 Diet Cancer prevention Energy intake Digestive cancer
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Effect of technological parameters on optical performance of fiber coupler
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作者 帅词俊 段吉安 钟掘 《Journal of Central South University of Technology》 EI 2007年第3期370-373,共4页
To find out the influence of technological parameters on optical performance of fused optical fiber device, the fiber coupler was served as subject investigated by using the fused biconical taper machining as experime... To find out the influence of technological parameters on optical performance of fused optical fiber device, the fiber coupler was served as subject investigated by using the fused biconical taper machining as experimental setup. Fused fiber coupler's optical performances such as insertion loss, excess loss, directivity and uniformity were tested with the optical test system that was constituted of tunable laser and optical spectrum analyzer. Especially the relationship between optical performance and drawing speed was investigated. The experimental results show that the optical performance is closely related to process conditions. At fused temperature of 1 200 ℃, there exists a drawing speed of 150 μms, which makes the device's performance optimum. Out of this speed region, the optical performance drops quickly. At drawing speed of 200 μms, the excess loss is relatively small when the fused temperature is above 1 200 ℃. So the technological parameters have close relationship with optical performance of the coupler, and the good performance coupler can't get until the drawing speed and fused temperature match accurately. 展开更多
关键词 optical fiber coupler fused biconical taper technological parameter optical performance
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Dark Matter Particle Explorer, the First Satellite of China Space Science Pilot Project
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作者 ZHU Zhencai 《Aerospace China》 2016年第1期4-11,共8页
The Dark Matter Particle Explorer(DAMPE) is the first high energy detector satellite in China,whose physics goal is to find evidence of the existence of dark matter particles by investigating the composition and energ... The Dark Matter Particle Explorer(DAMPE) is the first high energy detector satellite in China,whose physics goal is to find evidence of the existence of dark matter particles by investigating the composition and energy spectra of primary cosmic rays,especially those for electrons,positrons and gamma rays,over the dynamic range from 5 Ge V to 10 Te V.DAMPE is a satellite launched by China with the largest payload ratio,where the payload is composed of a BGO(Bismuth Germanate Oxide) Calorimeter,a Plastic Scintillator Detector,a Silicon Tungsten Tracker and a Neutron Detector.This paper introduces the technical scheme of DAMPE,including requirement analysis,composition,technical innovation,on-orbit status and prospect of development for the future. 展开更多
关键词 DAMPE PAYLOAD ORBIT Structure Thermal control
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浅谈农技推广技术能量在我州的释放途径
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作者 谢思清 《阿坝科技》 1992年第1期24-27,共4页
关键词 阿坝州 农业生产 农业先进实用技术 技术推广 农业科学能量 行政催化机制 组织机构
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Biomass-derived carbon materials with structural diversities and their applications in energy storage 被引量:20
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作者 江丽丽 盛利志 范壮军 《Science China Materials》 SCIE EI CSCD 2018年第2期133-158,共26页
Currently, carbon materials, such as graphene,carbon nanotubes, activated carbon, porous carbon, have been successfully applied in energy storage area by taking advantage of their structural and functional diversity. ... Currently, carbon materials, such as graphene,carbon nanotubes, activated carbon, porous carbon, have been successfully applied in energy storage area by taking advantage of their structural and functional diversity. However, the development of advanced science and technology has spurred demands for green and sustainable energy storage materials.Biomass-derived carbon, as a type of electrode materials, has attracted much attention because of its structural diversities,adjustable physical/chemical properties, environmental friendliness and considerable economic value. Because the nature contributes the biomass with bizarre micro structures,the biomass-derived carbon materials also show naturally structural diversities, such as OD spherical, 1D fibrous, 2D lamellar and 3D spatial structures. In this review, the structure design of biomass-derived carbon materials for energy storage is presented. The effects of structural diversity, porosity and surface heteroatom doping of biomass-derived carbon materials in supercapacitors, lithium-ion batteries and sodium-ion batteries are discussed in detail. In addition, the new trends and challenges in biomass-derived carbon materials have also been proposed for further rational design of biomass-derived carbon materials for energy storage. 展开更多
关键词 biomass-derived carbon materials supercapacitors lithium-ion batteries sodium-ion batteries
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Rapid development of proteomics in China: from the perspective of the Human Liver Proteome Project and technology development 被引量:3
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作者 LI Ning XU Zhong Wei +5 位作者 ZHAI Lin Hui LI Yan Chang FAN Feng Xu ZHENG Jun Jie XU Ping HE Fu Chu 《Science China(Life Sciences)》 SCIE CAS 2014年第12期1162-1171,共10页
Proteomics focuses on the systematic identification and quantification of entire proteomes and interpretation of proteins’biological functions.During the last decade,proteomics in China has grown much faster than oth... Proteomics focuses on the systematic identification and quantification of entire proteomes and interpretation of proteins’biological functions.During the last decade,proteomics in China has grown much faster than other research fields in life sciences.At the beginning of the second decade of the 21st century,the rapid development of high-resolution and high-speed mass spectrometry makes proteomics a powerful tool to study the mechanisms underlying physiological/pathological processes in organisms.This article provides a brief overview of proteomics technology development and representative scientific progress of the Human Liver Proteome Project in China over the past three years. 展开更多
关键词 PROTEOMICS LC-MS/MS HLPP protein-protein interaction protein posttranslational modification BIOINFORMATICS
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Scientific Evaluation and Regeneration of Eco-building Experience in Traditional Dwellings
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作者 LiuJiaping ZhangJiliang 《Science Foundation in China》 CAS 2003年第2期30-32,共3页
In 1996, Department of Engineering and MaterialSciences,National Natural Science Foundation (NSFC), accepted the suggestion made by some experienced members of CAS and published the key support project Green Architect... In 1996, Department of Engineering and MaterialSciences,National Natural Science Foundation (NSFC), accepted the suggestion made by some experienced members of CAS and published the key support project Green Architecture System and Dwelling Pattern in application guide for NSFC project. The project research group, led by Prof. 展开更多
关键词 traditional dwelling eco-building experience REGENERATION
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