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Frontal genesis of moisture atmosphere during the early 2008 persistent freezing-rain event in southern china

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Science china Earth sciences 2010年第3期53卷 454-464页

作者： QIAN WeiHong1 & FU JiaoLan1,2 1 Department of Atmospheric sciences, school of Physics, peking university, beijing 100871, china 2 National Meteorological Center of CMA, beijing, 100081, china 1. Department of Atmospheric sciences School of Physics Peking University Beijing 100871 China2. National Meteorological Center of CMA Beijing 100081 China

From January 10 to February 2, 2008, a severe and persistent freezing-rain event occurred in southern and southwestern china. Here we use an observational analysis to compare the persistent freezing-rain event in the early 2008 with the winter precipita- tion in the late 2007 over south of the Yangtze River (Jiangnan). The persistent freezing-rain event was directly linked to the activity of quasi-stationary front. The gradient of equivalent temperature (ET) can well indicate the frontal genesis of moist atmosphere (moisture front) and its activity as well as its relationship with precipitation belt. The precipitation types (snow and freezing rains) are related to the vertical structure of moisture front. The inversion profile of ET vertical distribution is a typical synoptic condition that caused the freezing-rain event. The horizontal gradient of ET with a criterion of 10℃ / 100 km, which reflects the accumulation and release of atmospheric energy, can be applied to predict the precipitation 5-10 days in advance.

关键词： freezing-rain event frontal genesis extended-range weather forecast winter Jiangnan

Study on urban water environmental support capacity

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Journal of Environmental sciences 1995年第4期7卷 430-434页

作者： Guo Huaicheng Ye Wenhu(Center of Environmental sciences , peking university , beijing 100871 , china) Ctr of Envmtl sciences Peking Univ Beijing China China

ＳｔｕｄｙｏｎｕｒｂａｎｗａｔｅｒｅｎｖｉｒｏｎｍｅｎｔａｌｓｕｐｐｏｒｔｃａｐａｃｉｔｙＧｕｏＨｕａｉｃｈｅｎｇ；ＹｅＷｅｎｈｕ（ＣｅｎｔｅｒｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓ，ＰｅｋｉｎｇＵｎｉｖｅｒ... 详细信息

ＳｔｕｄｙｏｎｕｒｂａｎｗａｔｅｒｅｎｖｉｒｏｎｍｅｎｔａｌｓｕｐｐｏｒｔｃａｐａｃｉｔｙＧｕｏＨｕａｉｃｈｅｎｇ；ＹｅＷｅｎｈｕ（ＣｅｎｔｅｒｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１００８７...

关键词： water environmental support capacity urban water environment development variablesi supportvariables.

|m| Partial wave treatment for two-dimensional Coulomb-scattering and Regge pole

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Science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 676-684页

作者： WANG Jing & ZENG Jinyan Department of Physics,Tsinghua university,beijing 100084,china school of Physics,peking university,beijing 100871,china Department of Physics Tsinghua University Beijing 100084 China school of Physics Peking University Beijing 100871 China

The symmetry and |m| partial-wave analysis for two-dimensional (2D) Coulomb-scattering is investigated. As a function of energyE, the |m| partial-wave scattering amplitudef |m|(θ) is analytically continuated to the, negativeE (complexk) plane, and it is found that the bound state energy eigenvalues (E<0) are just located at the poles off |m|(θ) on the positive imaginaryk axis as is expected. In addition, as a function of |m|,f |m|(θ) is analytically continuated to the complex |m| plane, the bound state energy eigenvalues are just located at the poles off |m|(θ) on the positive real |m| axis.

关键词： two-dimensional Coulomb scattering, |m| partial-wave, Regge pole.

Marginal cost pricing for coal fired electricity in coastal cities of china:The case of Mawan Electricity Plant in Shenzhen City, china

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Journal of Environmental sciences 2003年第3期15卷 401-412页

作者： ZHANG Shi-qiu, DUAN Yan-xin (Center for Environmental sciences, peking university, beijing 100871, china.) Center for Environmental sciences Peking University Beijing 100871 Chin

By developing a GDMOD model to estimate the environmental externalities associated with electricity generation, this project provides a detailed analysis of the damages and costs caused by different pollutants at varying distances from the Mawan Electricity Plant in Shenzhen, china. The major findings of this study can be summarized that (1) environmental damages caused by electricity production are large and are mainly imposed on regions far away from the electricity plant; (2) air pollution is the most significant contributor to the total damages, and SO_2, NOx, and particulate matter are the three major pollutants with highest damages; (3) the damages caused per unit of particulate, NOx, and SO_2 emissions are much higher than pollution treatment and prevention costs. The research results of this project showed that china needs to have a more effective levy system on SO_2, and a more manageable electricity tariff mechanism to internalize the environmental externalities. The results have also implications for pollution control strategies, compensation schemes as well as emission trading arrangements.

关键词： marginal cost pricing environmental damages environmental policy

Two Parameter Smooth Martingales on the Wiener Space

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Acta Mathematica Sinica,English Series 1997年第2期13卷 239-246页

作者： Liang Zongxia (school of mathematical Science,peking university,beijing 100871,china) school of mathematical Science Peking University

We prove that two parameter smooth continuous martingales have ∞-modification and establish a Doob’s inequality in terms of(p,r)-capacity for two parameter smooth martingales.

关键词： Two parameter smooth martingales ∞-modifications Doob’s inequality (p,r)-capacity

THE FUNCTION d_k(n) AT CONSECUTIVE INTEGERS

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Chinese Annals of Mathematics,Series B 1999年第4期20卷 473-478页

作者： MENG ZAIZHAO(Department of Mathematics, peking university, beijing 100871, china) peking Univ Dept Math Beijing 100871 Peoples R China

Let dk(n) denote the k-fold iterated divisor function (k ≥ 2). It is proved that for sufficiently large x) dk(n) = dk(n + 1) holds for >> x(log log x)-3 integers n ≤x.

关键词： Divisor function Multiplicative function Congruence

Skara hunanensis a new species of Skaracarida (Crustacea) from Upper Cambrian (Furongian) of Hunan,south china

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Progress in Natural Science:Materials International 2007年第8期17卷 934-942页

作者： Liu Jie Dong Xiping~(**) (school of Earth and Space Science,peking university,beijing 100871,china) [a]school of Earth and Space Science Peking University Beijing China

The fossils of Orsten-type preservation are as famous as Chengjiang Fauna in the world,but it was not until 2005 that the Orsten-type fossils represented by Skaraearida and Phosphatocopida were first reported to be found in western Hunan,South china. Here,we report the systematic paleontology of all the exquisitely preserved specimens belonging to *** were found at a same horizon of Upper Cambrian (Furongian) in Wangcun section,western Hunan,south china,assigned to a new species Skara huna- nensis *** hunanensis is characterized by small,soft-integumented,marine forms with slender,annulate body;labrum large and ventrocaudally directed;uniramous antennulae;biramous antennae and mandibulae;maxillas and maxillipeds of the same shape;all postantennular limbs join a short cephalic filter *** body has two tagmata:a cephalon with five pairs of well developed ap- pendages and a trunk composed of 11 ring-shaped conical segments.

关键词： Skara hunanensis Skaracarida Crustacea Upper Cambrian Furongian Hunan

Excessive Cu and Zn affecting on distribution of the metals and activities of glycolytic and nitrogen incorporating key enzymes in mycelia of ectomycorrhizal fungi Suillus bovinus

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Journal of Environmental sciences 2001年第3期13卷 337-341页

作者： HUANG Yi, TAO Shu(Department of Urban and Environmental sciences, peking university, beijing 100871, china. Department of Urban and Environmental sciences Peking University Beijing 100871 China. yhuang@***

Concentration of copper and zinc in isolated Suillus bovinus mycelia, used nutrient solution and 0.5 mol/L EDTA mycelia washing solution were measured to investigate the distribution of heavy metals in mycelia growth in excess copper or zinc nutrient solution. Treated with zinc, most of added zinc maintained in used solution, and 9.8%/14.6% was in/on mycelia in treatment, and in treatment 2 was 3.9%/8.0% in/on mycelia. In the copper applications, copper stimulated in more than on mycelia, i.e., 25.9%/4.5% in/on mycelia in treatment, and 7%/18.8% in/on mycelia while most of copper retained in used nutrient solution. Certain amount of copper or zinc uptake by mycelia led to pronounced influence on glycolysis and nitrogen incorporating process of Suillus bovinus, while the tested enzymes kept constant in treatment. In crude extracts of copper treatment 2 mycelia, activities of HK, PFK and GS were inhibited and decrease to 63%, 48% and 38% and GIDH increased by 68% of the control, respectively. The behaviors of these tested enzymes toward zinc corresponded in general with that towards copper. The potential protection of Suillus bovinus for its host plant under excess copper or zinc threaten was discussed.

关键词： Suillus bovinus ectomycorrhizal fungous copper zinc glycolysis nitrogen incorporate enzymes

Developmental sequence of Cambrian embryo Markuelia

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Chinese Science Bulletin 2007年第7期52卷 929-935页

作者： DONG XiPing1,2 1 school of Earth and Space sciences, peking university, beijing 100871, china 2 Laboratory of Palaeobiology & Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, Nan-jing 210008, china (email: dongxp@***) school of Earth and Space sciences Peking University Beijing 100871 China

Based on more exquisitely preserved specimens of Markuelia hunanensis recently recovered from Middle and Upper Cambrian in western Hunan and in the light of Synchrotron radiation X-ray tomo-graphic microscopy, the developmental sequence from cleavage through organogenesis to the pre-hatching of Cambrian embryo Markuelia, especially the developmental sequence during the pre-hatching stage, i.e. from the earliest period when the scalids and tail spines only took shape to the latest period (just about hatching), is established. This developmental sequence provides a pattern of embryonic development during the pre-hatching stage, which has not been established in the living scalidophorans (priapulids, loriciferans and kinorhynchs). Thus, it not only enriches our knowledge on the embryonic development of the extant descendants of Markuelia, but also opens a new window to the evolution and development of the animal.

关键词：寒武纪蠕虫化石胚胎发育序列两侧对称动物胚胎