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Prediction of Rock Burst with Deep Mining Excavation in Linglong Gold Mine

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Journal of university of Science and Technology beijing 2001年第4期8卷 241-243页

作者： Meifeng Cai, Jinan Wang, Shuanghong Wang Civil and environmental Engineering school, university of Science and Technology {3., beijing 100083. china Univ Sci & Technol beijing Sch Civil & Environm Engn Beijing 100083 Peoples R China

To predict rock burst in deep mining excavation in Linglong gold mine, systematical laboratory tests of mechanical properties of rock, in situ stress measurement and 3.D FEM analysis on energy distribution in rock mass surrounding deep mining rooms were carried out. According to various prediction criteria of rock burst, it is concluded that rock burst is liable to occur during deep mining excavation in the mine.

关键词： rock burst prediction deep mining excavation Linglong gold mine

Palaeorunoff estimations achieved from palaeoclimatic information for the southwest part of the North china Plain: an attempt to apply a climatological approach to palaeohydrology

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Journal of environmental sciences 2000年第3期12卷 330-336页

作者： WANG Hong\|ya, XIE Qiang (department of Urban and environmental sciences,{3.,beijing 100871, china) 北京大学北京 1 0 0 871

Palaeoclimatic scenario projecting annual temperature and annual precipitation is firstly formalized with data available and speculations for the southwest part of the North china Plain (3.— 3.°N, 115—119°E) during the last 25000 years. Then, with three regression equations relating annual runoff to annual precipitation and derived with data of modern hydrological and meteorological records, values of annual runoff are calculated in terms of the corresponding values of annual precipitation from this palaeoclimatic scenario for this region during this temporal interval. These results indicate that runoff is the most during 8000—3.00 a B.P. and the least during 25000—12000 a B.P.; runoff occurring during 12000—8000 a B.P. and during 3.00—0 a B.P. is less than the one occurring during 8000—3.00 a B.P. and more than the one occurring during 25000—12000 a B.P.; and the runoff occurring during 25000—12000 a B.P., 12000—8000 a B.P., and 3.00—0 a B.P. is respectively 43. 46 and 66 percent of the one occurring during 8000—3.00 a B.P. Values of bankfull discharge for palaeochannels of the Yellow River flowing in this region during the same interval are calculated from available estimates of slope of stream bed of these palaeochannels with a regression equation relating bankfull discharge to slope of stream bed and ratios of bankfull discharge are further calculated from these values for different groups of palaeochannel formed during different time spans embraced in this interval. To conduct a cross check, these values and ratios of bankfull discharge are compared to the corresponding values and ratios of runoff occurring during roughly the same time spans. The same direction and similar relative magnitude of changes of the surface water occurring in this region during the last 25000 years are indicated by these comparisons.

关键词： palaeorunoff the southwest part of the North china Plain palaeoclimate

Discovery of a pterodactylid pterosaur from the Yixian Formation of western Liaoning,china

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Chinese Science Bulletin 2001年第13期46卷 1112-1117页

作者： WANG Xiaolin & LU Junchang1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of sciences, beijing 100044, china 2. College of Earth sciences and Resources, china university of Geo-sciences, beijing 100083. china 3. department of Geological sciences, Southern Methodist university, Dallas, TX 75275, USA Institute of Vertebrate Paleontology Chinese Academy of Sciences Beijing 100044 China

A well-preserved pterosaur with nearly complete skull is described from the Lower Cretaceous Yixian Formation at Sihetun in western Liaoning. It is characterized by a low and long crestless skull, slender and pointed teeth, long metacarpal, nearly equal length of metatarsals I -III and short pedal digit V. It is referred to a new genus and species of the family Pterodactylidae: Haopterus gracilis gen. et sp. nov. This is the first pterosaur with a nearly complete skull from the Jehol Biota; it also represents the first non-controversial fossil record of Pterodactylidae in Asia. Haopterus is more derived than Pterodactylus from the Late Jurassic Solnhofen in Germany. This discovery extends the distribution of the family Pterodactylidae from Europe and Africa to Asia and its latest occurrence from the Late Jurassic to the Early Cretaceous. The discovery of Haopterus gracilis provides further evidence for the study of the originand radiation of the Jehol Biota; it also sheds new light on the evolution and

关键词： western Liaoning Early Cretaceous Yixian Formation Pterodactylidae.

Effects of Exposure to Trinitrotoluene on Male Reproduction

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Biomedical and environmental sciences 1993年第2期6卷 154-160页

作者： LI YI, JIANG QUAN-GUAN, YAO SHOU-QI, LIU WEI, TIAN GAO-JUN,AND GUI JING-WEIdepartment of occupational health, {3. of Public health, beijing Medical university, beijing ^Hebi Institute of occupational health, Henan Province Anyang Institute of occupational health, Henan Province Xinxiang Institute of occupational health, Henan Province, china Prof. Jiang Quan-guan, department of occupational health, {3. of Public health, beijing Medical university, beijing {23.china. department of occupational health School of Public Health Beijing Medical University China.

A cross-sectional study was performed in 2 plants located in Henan Province in 1990 for observing the reproductive and sexual functions of male workers exposed to trinitrotoluene (TNT). The TNT concentrations in the workplace air, except the packing site, were found to have exceeded MAC (1 mg/m3.. TNT exposed male workers complained of more sexual disorders such as impotence, the loss of libido and sexual hypoesthesia than the control group. Compared with the control group, the volume of semen and percentage of motile spermatozoawere found to have significantly decreased, and the sperm malformation incidence increased significantly in TNT exposed workers. The serum testosterone content in TNT exposed male workers was significantly decreased too.

关键词： TNT

Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

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Science china Chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1, YANG Limin1, XU Zhi3. ZHAO Ying2, LING Xiaofeng3. LI Qingbo1, WANG Jiansheng4, ZHANG Nengwei3. ZHANG Yuanfu1 & WU Jinguang1 1. The State Key Laboratory of Rare Earth Materials and Applications, College of Chemistry and Molecular Engineering, peking university, beijing 100871, china 2. Institute of Chemistry, Chinese Academy of {3., beijing 100080, china 3. department of Surgery, Third Hospital, peking university, beijing 100083. china 4. department of Oncology Surgery, the First Hospital of Xi’an Jiaotong university, Xi’an 710061, china Correspondence should be addressed to Wu Jinguang (email: wujg@***) 1. The State Key Laboratory of Rare Earth Materials and Applications College of Chemistry and Molecular Engineering Peking University 100871 Beijing China 2. department of Surgery Third Hospital Peking University 100083 Beijing China 3. Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 4. department of Oncology Surgery the First Hospital of Xi’an Jiaotong University 710061 Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 48 patients, including 3. normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 1545 cm-1, a shift of the amide I band to lower wave number, a decrease in the ～1450 cm-1 peak to less than the～1400 cm-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2, which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

Molecular mechanism of dehydrin in response to environmental stress in plant

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Progress in Natural Science:Materials International 2007年第3期17卷 237-246页

作者： ZHANG Yuxiu , WANG Zi and XU Jin (department of Bioengineering, school of Chemical and environmental Engineering, {3. university of Mining and Technology (beijing), beijing 100083. china department of Biology, Graduate university of Chinese Academy of sciences, beijing 100049, {3.) [a]department of Bioengineering School of Chemical and Environmental Engineering China University of Mining and Technology (Beiing) Beijing China [b]department of Biology Graduate University of Chinese Academy of Sciences Beijing China

Dehydrins, known as the D-11 subgroup of late embryogenesis abundant (LEA) protein, are an immunologically distinct family of proteins, which typically accumulate in desiccation-tolerant seed embryo or in vegetative tissues in response to various environmental stresses such as drought, salinity and freezing. The existence of conservative sequences designated as K, S, and Y segments is a structural feature of dehydrins, and the K segment found in all dehydrins represents a highly conserved 15 amino acid motif (EKKGIMDKIKEKLPG) and forms an amphiphilicα-helix. According to the arrangement of these domains and clustering analysis, dehydrins are subdivided into 5 subtypes: YnSK, Kn, KnS, SKn and YnK. Different types of dehydrins are induced by different environmental stress in plants. Study results showed that dehydrins might play important protective roles under abiotic stress via a number of different mechanisms, including improving or protecting enzyme activities by the cryoprotective activity in responding to freeze/thaw or dehydration; stabilizing vesicles or other endomembrane structures by function as the membrane stabilizer during freeze induced dehydration, and preventing the membrane system from the oxidative damage induced by reactive oxygen radicals as the radical scavenger. Here, the gene expression and molecular mechanisms of dehydrin in response to stress in plants are discussed.

关键词： dehydrin stress mechanism.

On conformal measures for infinitely renormalizable quadratic polynomials

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Science china Mathematics 2005年第10期48卷 1411-1420页

作者： HUANG Zhiyong~1 JIANG Yunping~(2,3. & WANG Yuefei~3.1. school of Information,Renmin university of china,{3. 100872,china 2. department of Mathematics,Queens College,City university of New York,NY 113.7,USA department of Mathematics,Graduate school,City university of New York,New York,NY 10016,USA 3. Academy of Mathematics and Systems Science,Chinese Academy of sciences,{3. 100080,china 1. school of Information Renmin University of China 100872 Beijing China 2. department of Mathematics Queens College City University of New York 11367 NY USA 3. department of Mathematics Graduate School City University of New York 10016 New York NY USA 4. Academy of Mathematics and Systems Science Chinese Academy of Sciences 100080 Beijing China

We study a conformal measure for an infinitely renormalizable quadratic polynomial. We prove that the conformal measure is ergodic if the polynomial is unbranched and has complex bounds. The main technique we use in t... 详细信息

关键词： Julia set, conformal measure, three-dimensional puzzle, infinitely renormalizable quadratic polynomial.

Hydrogen sulfide ameliorates vascular calcification induced by vitamin D3.plus nicotine in rats

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Acta Pharmacologica Sinica 2006年第3期27卷 299-306页

作者： Sheng-ying WU~(2,6) Chun-shui PAN~3.Bin GENG~3.Jing ZHAO~3.Fang YU~3.Yong-zheng PANG~3.Chao-shu TANG~4 Yong-fen QI~(3.4,5) ~2Institute of Cardiovascular Disease,peking university First Hospital.beijing 10003. ~3.3. of Physiology and Pathophysiology,peking university health Science Center,beijing 100083.china,~4Key Laboratory of Molecular Cardiovascular Science,Ministry of Education,beijing 100083.china 2Institute of Cardiovascular Disease Peking University First Hospital Beijing 100034 China 3.0} of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.0} of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.0} of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.0} of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.0} of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 4Key Laboratory of Molecular Cardiovascular Science Ministry of Education Beijing 100083 China 4Key Laboratory of Molecular Cardiovascular Science Ministry of Education Beijing 100083 China

Aim:To investigate the role of the endogenous cystathionine γ-synthase(CSE)/hydrogen sulfide(H2S)pathway in vascular calcification in ***:A ratvascular calcification model was established by administration of vitamin D3.plusnicotine(VDN).The amount of CSE and osteopontin(OPN)mRNA was deter-mined by using semi-quantitative reverse-transcription polymerase chain *** calcium content,45Ca2+accumulation and alkaline phosphatase(ALP)activitywere measured.H,S production and CSE activity were ***:yonKossa staining produced strong positive black/brown staining in areas amongthe elastic fibers of the medial layer in the calcified *** calcium content,45Ca2+accumulation and ALP activity in calcified arteries increased by 6.77-,1.42-,and 1.87-fold,respectively,compared with *** expression of the OPNgene was upregulated(P3..8%,40.75% and 63.5% lowerin the low-dosage NariS group than in the VDN group,respectively(P3.9%,3..8 % and 46.2% lower in the aorta in the high-dosage NariS group than in theVDN group,respectively(P<0.01).The expression of the OPN gene ***:The production of H,S,and CSE activity were de-creased and CSE gene expression was downregulated in rats with vascularcalcification.H2S can ameliorate vascular calcification,suggesting that the H2S/CSE pathway plays a regulatory role in the pathogenesis of vascular calcification.

关键词： hydrogen sulfide cystathionine-lyase vascular calcification mRNA

The evolution and morphological stability of a spherical crystal

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Science china(Technological sciences) 2008年第3期51卷 225-243页

作者： CHEN MingWen1,2, WANG ZiDong2 & XU JianJun3.4 1 school of Applied sciences, university of Science and Technology {3., beijing 100083. china 2 school of Materials Science and Engineering, university of Science and Technology {3., beijing 100083. china 3.school of Mathematical sciences, Nankai university, Tianjin 3.0071, china 4 {13. of Mathematics and Statistics, McGill university, Montreal H3. 2K6, Canada 1. school of Applied sciences University of Science and Technology Beijing Beijing 100083 China 2. school of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China 3. school of Mathematical sciences Nankai University Tianjin 300071 China 4. department of Mathematics and Statistics McGill University Montreal H3A 2K6 Canada

The growth model of a spherical crystal in the undercooled melt including the surface energy, interfacial kinetics and convective flow is established. The effect of the convective flow induced by a small far field flow on the evolution and morphological stability of the interface of the spherical crystal is studied. The interface shape of the spherical crystal, which is affected by the far field flow, and the dispersion relation of the growth rate of amplitude of the perturbed interface are derived. It is shown that the convection induced by the far field flow makes the interface of the growing spherical crystal further grow in the upstream direction of the far field flow and inhibit growth in the downstream direction; the interface of the decaying spherical crystal further decays in the upstream direction and inhibits decay in the downstream direction. The theoretical result suggests that both the growth of the sphere in the upstream direction and the decay of the sphere in the downstream direction make the spherical crystal tend to evolve into an oval; the morphological stability of the interface depends on a certain radius R c such that the spherical crystal is unstable when its radius is greater than R c and stable when its radius is less than R c . The surface energy and interfacial kinetics have strong stabilizing effects on the growth of the spherical crystal. In the meantime interfacial kinetics is a table factor of the interface when the interface of the sphere is growing; it is an unstable factor of the interface when the interface is decaying.

关键词： solid-liquid interface spherical crystal convective flow crystal growth morphological stability