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EXISTENCE AND ASYMPTOTIC BEHAVIOR OF THE SOLUTIONS FOR A NONLINEAR ELLIPTIC EQUATION ARISING IN ASTROPHYSICS

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Acta Mathematica Scientia 2006年第2期26卷 229-245页

作者：唐仲伟 school of mathematical sciences{3. Beijing 100875China

The author first analyzes the existence of ground state solutions and cylindrically symmetric solutions and then the asymptotic behavior of the ground state solution of the equation -△u =φ（r）u^p-1, u 〉 0 in R^N, u ∈ D^1,2（R^N）, where N ≥ 3. x = （x^1,z） ∈ R^K×R^N-K,2 ≤ K ≤ N,r = ｜x′｜. It is proved that for 2（N-s）/（N-2）〈 p 〈 2^＊ = 2N/（N - 2）, 0 〈 s 〈 2, the above equation has a ground state solution and a cylindrically symmetric solution. For p = 2^＊, the above equation does not have a ground state solution but a cylindrically ***, and when p close to 2^＊, the ground state solutions are not cylindrically symmetric. On the other hand, it is proved that as p close to 2＊, the ground state solution Up has a unique maximum point xp = （x′p, Zp） and as p → 2^＊, ｜x′p｜ → r0 which attains the maximum of φ on R^N. The asymptotic behavior of ground state solution Up is also given, which also deduces that the ground state solution is not cylindrically symmetric as p goes to 2^＊.

关键词： Cylindrical symmetry asymptotic behavior ground state solution

Biodegradation of polycyclic aromatic hydrocarbons in sediments from the Daliao River watershed, China

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Journal of Environmental sciences 2009年第7期21卷 865-871页

作者： QUAN Xiangchun, tang Qian, HE Mengchang, YANG Zhifeng, LIN Chunye, GUO Wei State Key Joint Laboratory of Environmental Simulation and Pollution Control, school of Environment, beijing normal university,{3., China. State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

The Daliao River, as an important water system in Northeast China, was reported to be heavily polluted by polycyclic aromatic hydrocarbons （PAHs）. Aerobic biodegradations of four selected PAHs （naphthalene, phenanthrene, fluorene and anthracene） alone or in their mixture in river sediments from the Daliao River water systems were studied in microcosm systems. Effects of additional carbon source, inorganic nitrogen and phosphorus, temperature variation on PAHs degradation were also investigated. Results showed that the degradation of phenanthrene in water alone system was faster than that in water-sediment combined system. Degradation of phenanthrene in sediment was enhanced by adding yeast extract and ammonium, but retarded by adding sodium acetate and not significantly influenced by adding phosphate. Although PAHs could also be biodegraded in sediment under low temperature （5~C）, much lower degradation rate was observed. Sediments from the three main streams of the Daliao River water system （the Hun River, the Taizi River and the Daliao River） demonstrated different degradation capacities and patterns to four PAHs. Average removal rates （15 or 19 d） of naphthalene, phenanthrene, fluorene and anthracene by sediment were in the range of 0.062-0.087, 0.005-0.066, 0.008- 0.016 and 0-0.059 mg/（L.d）, respectively. As a result, naphthalene was most easily degraded compound, anthracene was the hardest one. In multiple PAHs systems, the interactions between PAHs influenced each PAH biodegradation.

关键词： biodegradation the Daliao River microcosm polycyclic aromatic hydrocarbon sediment

The effects of proteasome inhibitor lactacystin on mouse oocyte meiosis and first cleavage

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Science China(Life sciences) 2005年第3期48卷 287-294页

作者： TAN Xin 1,3., PENG An 2 , WANG Yongchao 2 & tang Zuoqing 3.1. school of Life sciences and Technology, {3. Institute of Technology, {3. 100081, China 2. College of Life sciences, beijing normal university, beijing 100875, China 3. College of Basic Medicine, Capital university of Medical sciences, {3. 100054, China school of Life sciences and Technology Beijing Institute of Technology Beijing100081 China College of Basic Medicine Capital University of Medical Sciences Beijing100054China College of Life sciences Beijing Normal University Beijing100875 China College of Basic Medicine Capital University of Medical Sciences Beijing100054China

In order to study the effects of ubiquitin-proteasome pathway (UPP) on mouse oo- cyte meiosis and cleavage, oocytes undergoing maturation and parthenogenetic activation and 1-cell embryos were treated with lactacystin, a specific inhibitor of proteasome. The results indi- cated that the rate of GVBD was not influenced by the treatment, but polar body extrusion, par- thenogenesis and first cleavage were inhibited. Immunofluorescent staining using anti β-tubulin antibody indicated that the continuous treatment of lactacystin from GV stage disorganized microtubules and spindle assembly. When metaphase stage oocytes were treated with the drug, the already formed spindle structure was not affected , but the oocytes were arrested at meta- phases. The 1-cell embryos were arrested at interphase or metaphase of first mitosis when they were incubated in the drug. Proteasome regulatory subunit PA700 was located in the spindle region, as indicated by immunofluorescence. These results suggest that UPP has effects on the process of oocyte meiosis and early cleavage in many aspects, including normal organization of spindle at prophase and segregation of chromosomes at anaphase for normal meiosis.

关键词： proteasome, oocyte, meiosis, cleavage.

Key points on temperature change of the past 2000 years in China

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Progress in Natural Science:Materials International 2004年第8期 82-89页

作者： GE Quansheng 1, ZHENG Jingyun 1*, MAN Zhimin 2, FANG Xiuqi 3.1 and ZHANG Piyuan 1(1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, beijing 100101, China 2. Institute of Chinese History Geography, Fudan {3., Shanghai 20043., China 3. school of Geography, beijing normal university, beijing 100875, China) Institute of Geographic sciences and Natural Resources Research，Chinese Academy of sciences，beijing 100101，China Institute of Chinese History Geography，Fudan university，Shanghai 20043.，China school of Geography，beijing normal {3.，beijing 100875，China Institute of Geographic sciences and Natural Resources Research，Chinese Academy of sciences，beijing 100101，China

Temperature change of the past 2000 years in China is discussed based on the winter half-year temperature series of the past 2000 years in eastern China reconstructed recently, and other related studies. The main conclusions are as follows: (1) The Little Ice Age (LIA) in China began in the early of the 14th century (13.0s) and ended in the beginning of the 20th century (1910s), which was composed of four evident cold stages and three short warming stages. The cold period in the Wei, Jin and South-North dynasties (210s～560s) was the only one comparable with LIA for the past 2000 years. (2) The Medieval Warm Period (MWP) in China began in the 93.s and ended in the 13.0s, which was composed of two warm stages over 100 years and a cold stage less than 100 years. (3. The climate in the Sui and tang dynasties should be divided into two stages: the climate in the 570s～770s was as warm as that in the 20th century; while the temperature in the 780s～920s was lower than that in the 1950s～1970s. (4) In eastern China as a whole, winter half-year temperature variation with over 1 ℃ occurred between the cold and warm stages on centennial scale, while the changing rate exceeded 1.0 ℃ per century. (5) There exists an about 13.0-year periodicity in the historical temperature change. Inferred from the periodicity, the most likely historical analogue for the warming in the 20th century is the warm stage of the Sui and tang dynasties (570s～770s), instead of the Medieval Warm Period. (6) Although it was critically warm, the temperature of the 20th century in eastern China is still within the threshold of the variability of the last 2000 years.

关键词： eastern China past 2000 years temperature change.

我国图书情报学研究生教育发展状况及策略探讨

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图书情报工作 2004年第4期48卷 85-89页

作者：唐雪琳北京师范大学管理学院北京100875

从培养目标、研究方向与课程设置、人才培养评估体系、教学资源及师资队伍建设等方面分析我国图书情报学研究生目前教育发展的状况,并针对上述方面存在的问题,提出解决策略。

关键词：中国图书馆学情报学研究生教育课程设置评估体系教学资源教师培养

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北宋政情、政风下的转对制

史学月刊 2010年第11期 40-50页

作者：陈晔北京师范大学历史学院北京100875

转对是关乎君臣沟通的重要的奏对制度,其兴起虽可远溯至中唐,但迭经晚唐、五代的变迁,实际上已日渐衰微。宋初因现实政治的需要,转对得以在五代的模式下重整,形制、功用去唐已远,本是一种临时性议政求言举措。降至仁宗时期,言路已广,皇... 详细信息

转对是关乎君臣沟通的重要的奏对制度,其兴起虽可远溯至中唐,但迭经晚唐、五代的变迁,实际上已日渐衰微。宋初因现实政治的需要,转对得以在五代的模式下重整,形制、功用去唐已远,本是一种临时性议政求言举措。降至仁宗时期,言路已广,皇权亦固,加之朝野纷纷,转对是否必要竟成疑问,幸有士大夫为求扩大政治参与而对其意义再度强调与发掘,该制存在价值方在新的意义体系中得到承认。此后历经神宗朝的实践,转对在北宋晚期虽因政情所限,运行尚乏活力,但已由当时的政治文化陶铸成一种稳定的集体行为与制度惯例,影响着此后的政治运作。

关键词：北宋转对听政政治参与士大夫

孔子何以颂“葛”——试析上博简《诗论》第16简的一个问题

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史学集刊 2006年第4期 7-12页

作者：晁福林北京师范大学历史学院北京 100875

上博简《诗论》第24简应当系联于第16简之后,简文的这段话,从语意上看,孔子是在解释“葛”何以被歌颂的原因。第24简开首的略有残缺的三个字应当读为“以蒙棘”。“蒙棘”之语见于《唐风·葛生》篇。此篇意蕴,曾长期被误解,独王夫之发... 详细信息

上博简《诗论》第24简应当系联于第16简之后,简文的这段话,从语意上看,孔子是在解释“葛”何以被歌颂的原因。第24简开首的略有残缺的三个字应当读为“以蒙棘”。“蒙棘”之语见于《唐风·葛生》篇。此篇意蕴,曾长期被误解,独王夫之发千古之矇,指出它是歌颂晋君关爱民众以成就霸业的诗篇。今得《诗论》相关简文印证,不仅使《葛生》诗意大白,而且对于认识孔子的仁学理论,也有重要启发。

关键词：孔子诗论《唐风》仁学

Fully polarized Compton scattering in plane waves and its polarization transfer

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Matter and Radiation at Extremes 2024年第3期9卷 45-56页

作者： Suo tang Yu Xin Meng Wen Mamat Ali Bake Baisong Xie College of Physics and Optoelectronic Engineering Ocean University of ChinaQingdaoShandong 266100China Department of Physics Hubei UniversityWuhan 430062China Xinjiang Key Laboratory of Solid State Physics and Devices School of Physics Science and TechnologyXinjiang UniversityUrumqi 830017China Key Laboratory of Beam Technology of the Ministry of Education and College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China

Fully polarized Compton scattering from a beam of spin-polarized electrons is investigated in plane-wave backgrounds in a broad intensity region from the perturbative to the nonperturbative *** the perturbative regime,polarized linear Compton scattering is considered for investigating polarization transfer from a single laser photon to a scattered photon,and in the high-intensity region,the polarized locally monochromatic approximation and locally constant field approximation are established and are employed to study polarization transfer from an incoming electron to a scattered *** numerical results suggest an appreciable improvement of about 10%in the scattering probability in the intermediate-intensity region if the electron’s longitudinal spin is parallel to the laser *** longitudinal spin of the incoming electron can be transferred to the scattered photon with an efficiency that increases with laser intensity and collisional *** collision between an optical laser with frequency1 eV and a 10 GeV electron,this polarization transfer efficiency can increase from about 20%in the perturbative regime to about 50%in the nonperturbative regime for scattered photons with relatively high energy.

关键词： polarized scattered transfer

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汉语儿童早期语音意识的发展

心理科学 2009年第2期32卷 312-315页

作者：唐珊伍新春北京师范大学心理学院儿童阅读与学习研究中心北京100875

本研究采用四类语音意识任务(音节、首音、韵脚、声调)考察了幼儿园小中大班和小学一年级儿童的汉语语音意识发展的年龄特征和发展规律。研究结果表明,学前儿童的汉语语音意识已经开始发展,其中音节意识发展最早,其次是韵脚意识,声调意... 详细信息

本研究采用四类语音意识任务(音节、首音、韵脚、声调)考察了幼儿园小中大班和小学一年级儿童的汉语语音意识发展的年龄特征和发展规律。研究结果表明,学前儿童的汉语语音意识已经开始发展,其中音节意识发展最早,其次是韵脚意识,声调意识和首音意识的发展相对较晚。

关键词：汉语语音意识幼儿园儿童一年级儿童