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非标准宇宙模型新动向

天文学进展 1991年第4期9卷 253-262页

作者：卞毓麟中国科学院北京天文台

热大爆炸模型因成功解释了许多重要观测事实而为多数宇宙学家所接受,并获得了标准模型的称号。然而自80年代后期以来,它却受到了一系列新观测事实的严重挑战。大爆炸宇宙学家们正在原来的基础上继续发展,以求找到问题的答案。一些本来... 详细信息

热大爆炸模型因成功解释了许多重要观测事实而为多数宇宙学家所接受,并获得了标准模型的称号。然而自80年代后期以来,它却受到了一系列新观测事实的严重挑战。大爆炸宇宙学家们正在原来的基础上继续发展,以求找到问题的答案。一些本来就不赞成标准模型的宇宙学家则对它提出了全面的批评。本文旨在对这些不同见解作一简介,它主要涉及对微波背景的认识、非宇宙学红移问题、年轻星系、离散天体的演化以及非标准模型本身的一些情况。

关键词：宇宙模型宇宙学

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一种用于降维和盲源分离的主独立元神经网络

数据采集与处理 2004年第3期19卷 239-242页

作者：郭振华王宏华中科技大学机械科学与工程学院武汉430074 中国科学院自动化研究所北京100080

经典主元分析和主元神经网络常以主元所能提取总的系统方差来确定主元数目 ,这隐含假设系统数据是高斯分布 ,所提取的主元之间相互无关 ,但不一定相互独立 ,从而难以实现非高斯系统数据的降维和信源分量。针对非高斯随机系统数据的降维... 详细信息

经典主元分析和主元神经网络常以主元所能提取总的系统方差来确定主元数目 ,这隐含假设系统数据是高斯分布 ,所提取的主元之间相互无关 ,但不一定相互独立 ,从而难以实现非高斯系统数据的降维和信源分量。针对非高斯随机系统数据的降维和信源分离问题 ,提出一种基于二阶 Renyi近似熵指标的主独立元神经网络 ,并给出熵的近似计算方法及相应的梯度学习算法。仿真实验证明 ,该主独立元网络不仅能对数据降维压缩 ,还能有效地分离出普通主元分析法所不能提取的独立信源信息。

关键词：主元分析主元神经网络盲源分离降维 PCA Renyi熵信源分量

Crystallization of the complex of tissue plasminogen activator with an anti-neurotic hexapeptide

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Crystallization of the complex of tissue plasminogen activat...

中国化学会第五届全国结构化学学术会议

作者： Shi,Xiaoli~1 Zeng Tu~2 Huang,Mingdong State Key Laboratory of structural Chemistry,Fujian Institute of Research on the Structure of Matter,chinese academy of sciences,Fuzhou 350002,china The Graduate School of chinese academy of sciences,beijing 100049,china

＜正＞Tissue-type plasminogen activator（tPA）is a multidomain serine proteinase of trypsin-family, and comprises five structural domains:the finger domain,an epidermal growth factor-like domain, two kringle domains a...

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亚临界水脱除煤中硫的实验研究

燃料化学学报 2005年第5期33卷 630-632页

作者：王刚王宝凤李文陈皓侃李保庆中国科学院山西煤炭化学研究所煤转化国家重点实验室

Pre-combustion desulfurization of coal is an important method to control SO2 emission in a coal fired power plant. Desulfurization of Huayinshan coal with sub-critical water in a semi-continuous reactor was studied. The effects of temperature （320℃450℃）, pressure （5MPa15MPa） and extraction time （10min100min） on the removal of sulfur and weight loss of coal were examined. The results show that with the increase of temperature, pressure and reaction time the weight loss of coal and the removal of total sulfur in coal increase, and with the increase of temperature and reaction time the removal of organic sulfur increases. At higher temperature, sub-critical water has the characteristic of selective desulfurization. The inorganic sulfur removal is mainly a physical process. Below 370℃ the organic sulfur removal is higher than inorganic sulfur removal, but above 370℃ it is opposite. It is suggested that considering the practicability, the suitable high temperature and low pressure should be taken in the sub-critical water operation condition.

关键词：亚临界水煤硫脱除

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亚临界水条件下煤中汞的脱除

燃料化学学报 2004年第5期32卷 513-516页

作者：王宝凤王刚李文陈皓侃李保庆中国科学院山西煤炭化学研究所煤转化国家重点实验室

运用半连续反应装置对山西吴家坪煤中汞在亚临界水中的脱除规律进行了研究。考察了反应温度为290℃、320℃、350℃、380℃,反应压力为5MPa、10MPa、15MPa,萃取时间为10min、30min、60min、100min时对汞脱除率的影响。结果表明,在290℃～... 详细信息

运用半连续反应装置对山西吴家坪煤中汞在亚临界水中的脱除规律进行了研究。考察了反应温度为290℃、320℃、350℃、380℃,反应压力为5MPa、10MPa、15MPa,萃取时间为10min、30min、60min、100min时对汞脱除率的影响。结果表明,在290℃～380℃,随着温度升高,汞脱除率明显增加;在5MPa～15MPa,压力越大,汞的脱除率也越大;在10min～100min,随着萃取时间的延长,汞脱除率增加;在380℃,15MPa,1h,汞的脱除率最大可达96%以上。

关键词：亚临界水煤汞脱除

House dust mite major allergens Der p1 promote the production of IL-8 and MUC5AC in human airway-derived epithelial cells by NF-κB mechanism

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House dust mite major allergens Der p1 promote the productio...

中国药理学会生化与分子药理学专业委员会网络药理学研讨会

作者： Renping Liu~1,Qi Hou~2,and Aiming Meng~1 1 Institute of Radiation Medicine,chinese academy of Medical sciences & Peking Union Medical College,Tianjin 300192,china 2 Institute of Materia Medica,chinese academy of Medical sciences & Peking Union Medical College,beijing 100050,china

＜正＞Backgroud:House dust mite allergens（HDM） is the most commonly encountered pathogen of humans,predominantly causing bronchoconstriction in asthma patients and inducing an inflammatory response in the lungs dune...

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Nanostructuring Electrode Materials for High Power Lithium-Ion Batteries

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Nanostructuring Electrode Materials for High Power Lithium-I...

ICAM Workshop Physics of Novel Energy Materials

作者： Yong-Sheng Hu beijing National Laboratory for Condensed Matter Physics, Institute of Physics, chinese academy of sciences, beijing 100190, china

One of the greatest challenges for our society is providing powerful electrochemical energy storage and conversion devices with high energy/power densities and high safety as well as low cost. Among all these devices,

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The boundary layer characteristics in the heavy fog formation process over beijing and its adjacent areas

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Science china Earth sciences 2005年第Z2期48卷 88-101页

作者： ZHANG Guangzhi, BIAN Lingeng, WANG Jizhi, YANG Yuanqin, YAO Wenqing & XU Xiangde HWL of chinese academy of Meteorological sciences, beijing 10008, china National Meteorological Center, beijing 100081, china HWL of chinese academy of Meteorological sciences Beijing 10008 China National Meteorological Center Beijing 100081 China

By utilizing the Atmospheric Boundary Layer (ABL) observational data made available from the project "973" under the auspices of the Ministry of Science and Technology of the People's Republic of china - entitled the beijing City Air Pollution Observation Field Experiment (BECAPEX), including the measurements by a wind profiler, captive airships, tower-based boundary layer wind and temperature gradient observational instruments (ultrasonic anemometers and electronic thermometers), air composition samplers, conventional upper-air, surface and Automatic Weather Stations (AWS) observations, this paper herewith analyzes, in a comprehensive manner, the occurrence of a heavy fog event over beijing in February 2001, including its formation, development, persistence, dynamic and thermodynamic features as well as evolving stratification structures within the boundary layer at different stages. The results suggested: (i) as a typical case of urban heavy fog, before the fog onset over beijing, a temperature inversion existed in the lower atmosphere, the smokes and the pollutants like SO2 and NO2 had been accumulated at a lower level. Proceeding the fog event, with the increase of SO2 and NO2 concentrations, condensability increased sharply. On the contrary, during the fog process, with increasing condensability, SO2 and NO2 concentrations decreased. This indicated that, acting as condensation nucleus, these accumulated pollutants were playing a key role in catalyzing the fog condensation. (ii) By analyzing mean gradient-, pulsation- and turbulence-distribution patterns derived from the wind measurements taken by the aforementioned tower-based instruments, they all indicated that about 10 hours before the fog onset, a signal foretelling potential strong disturbances in the lower boundary layer was detected, and a significant rise of both mean and disturbance kinetic energies was observed, revealing that the low-level wind shear was strengthened before the fog onset, consequentl

关键词： beijing heavy fog, SO2 and NO2, catalyzing fog condensation, disturbance kinetic energy signal.

One-dimension position sensitive MCP detector using a parallel strips readout anode

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One-dimension position sensitive MCP detector using a parall...

第十六届全国原子与分子物理学术会议

作者： Wei Wang~* 1,Deyang Yu~* 2,Fangfang Ruan~*,MingWu Zhang~(*+) and Xiaohong Cai~* * Institute of Modern Physics.chinese academy of sciences.Lanzhou 730000,china + Graduate School of chinese academy of sciences.beijing 100039,china

Synopsis We have developed a one-dimension position sensitive MCP detector based on a new parallel micro-strips readout *** position resolution of the detector is 0.2mm.

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