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Slope-gully erosion relationship in small catchments of the middle reaches of the Yellow River

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Journal of Geographical sciences 1999年第2期9卷 105-115页

作者： CHEN Hao(institute of Geography, chinese academy of sciences, beijing 100101, china)

The slope-gully erosion relationship in small catchments of the middle reaches of the Yellow River has long been a topic concerned by relevant departments in china Slope-gully relationship in typical small catchment is determined determined on the concept of net increase of sediment yield by using analytical method of sediment formation at different positions in the catchment The result shows that sediments in a small catchment in the middle reaches of the Yellow River mainly come from slopes. ms paper indicated that the sediment sources from slopes are roughly 55, 60, 78 and 85 % of the total sediment yield of a small catchment in Yangdaogou. Wangjiagou. Jiuyuangou and Nanxiaohegou, respectively, due to impacts of varying degress from slope runoff.

关键词： small catchment slope-gully erosion relationship sediment sources the middle reaches of the Yellow River

Cloning,expression and characterization of a nucleoside diphosphate kinase (NDPK) gene from tobacco

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Progress in Natural Science:Materials International 2007年第08期17卷 906-912页

作者： Zhou Qiyun~(1,2**) Xie Zongming~(1**) Zhang Zhigang~1 Cao Yangrong~1 Zhang jinsong~(1***) Chen Shouyi~(1***) (1.National Key Laboratory of Plant Genomics,institute of Genetics and Developmental Biology,chinese academy of sciences,beijing100101,china 2.Graduate University of chinese academy of sciences,beijing 100039,china) [a]National Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China [b]Graduate University of chinese academy of sciences Beijing China

Nucleoside diphosphate kinase (NDPK) is a housekeeping enzyme that maintains the intracellular levels of all (d)NTPs used in biosynthesis except *** we report that a full-length cDNA encoding nucleoside diphosphate kinase (NDPK) was cloned us- ing yeast two-hybrid approach.A tobacco NDPK gene was obtained and designated as ***1 is 704 bp in length and en- codes a putative 16.2 kD protein of 148 amino *** analysis showed that NtNDPK1 is highly homologous to other plant NDPK genes and identified as type I (NDPK1).RNA-gel blot analysis showed that there was no significant difference of NtNDPK1 ex- pression in roots,stems,leaves and *** expression of NtNDPK1 was induced by ABA and PEG and repressed by NaCl,but not significantly affected by Paraquat,wounding and low temperature (4℃) treatments,indicating that NtNDPK1 may play a certain role in response to abiotic *** vitro phosphorylation assay demonstrated that NtNDPK1 had autophosphoryLation activity.

关键词： abiotic stress autophosphorylation activity NtNDPK1 tobacco yeast two-hybrid

Simulations for terrestrial planets formation

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 794-803页

作者： ZHANG Niu 1,2 &JI JiangHui 2,3 1Graduate University of chinese academy of sciences,beijing 100049,china 2Purple Mountain Observatory,chinese academy of sciences,Nanjing 210008,china 3 National Astronomical Observatories,chinese academy of sciences,beijing 100012,china Graduate University of chinese academy of sciences Beijing 100049 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

In this paper,the formation of terrestrial planets in the late stage of planetary formation is investigated using the two-planet *** that time,the protostar formed for about 3 Ma and the gas disk *** the model,the perturbations from Jupiter and Saturn are *** of the mass of outer planet,and the initial eccentricities and inclinations of embryos and planetesimals are also *** results show that,terrestrial planets are formed in 50 Ma,and the accretion rate is about 60%-80%.In each simulation,3-4 terrestrial planets are formed inside"Jupiter"with masses of 0.15 -3.6M⊕.In the 0.5-4 AU,when the eccentricities of planetesimals are excited,planetesimals are able to accrete material from wide radial *** plenty of water material of the terrestrial planet in the Habitable Zone may be transferred from the farther places by this *** could also happen a few times between two major planets only if the outer planet has a moderate mass and the small terrestrial planet could survive at some resonances over time scale of 10 8 *** one of our simulations,commensurability of the orbital periods of planets is very ***,a librating-circulating 3:2 configuration of mean motion resonance is found.

关键词： astrophysics exoplanet planetary formation n-body simulation

2023 Guideline for the management of hypertension in the elderly population in china

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Journal of Geriatric Cardiology 2024年第6期21卷 589-630页

作者： Hypertension Branch of chinese Geriatrics Society,beijing Hypertension Association,National Clinical Research Center of the Geriatric Diseases Qi HUA Li FAN Zeng-Wu WANG Jing LI 不详 Xuanwu Hospital Capital Medical UniversityBeijingChina chinese PLA General Hospital BeijingChina Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Preamble Hypertension is one of the most common chronic diseases and the primary risk factor for stroke,myocardial infarction and even cardiovascular *** than half of the elderly population has high blood *** people are a unique group,and strategies for the prevention,diagnosis,evaluation,and treatment of hypertension in elderly individuals differ significantly from those in the general population.

关键词： hypertension prevention diagnosis

Approaches to the systematic tourism planning-a case study of the Ningxia Hui Autonomous Region

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Journal of Geographical sciences 1999年第4期9卷 362-370页

作者： LIU Feng(institute of Geography, chinese academy of sciences, beijing 100101, china)

The rapid development of tourism makes a further demand for tourism planning in china. It is necessary to find out some new effective approaches and patterns to guarantee the continuity andpracticality of the planning. The approach of systematic tourism planning is a way along this *** paper advances the theory that the tourism planning is in fact the Systematic tourism planningand that the planning must take into account the operation of the whole tourism system and befocused on the general optimization of all the subjects concerned. Besides, the planning should bemulti-dimensional. must optimize and balance the economic, environmental and social-culturalfactors in achieving sustainable development and must be monitored to ensure the accomplishment ofthe objectives and the implementation of the recommended policy. The systematic planning shouldalso embody a continuity or a guideline of progressiveness, with an adaptability to the possiblechanges in the future . The paper, with the Ningxia Hui Autonomous Region as a case, gives a briefpresentation of the overall theoretical pattern of the systematic tourism planning, the essentialelements in the systematic planning and the practicable approaches.

关键词： tourism planning systematic tourism planning Ningxia

Land-use development in Liaocheng prefecture of china after 1949

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Journal of Geographical sciences 1998年第4期8卷 30-47页

作者： LENG Shuying institute of Geography, chinese academy of sciences, beijing 100101, china

s—This paper generalizes land use development in Liaocheng Prefecture, Shandong Province, china; describes land use changes during different period of time; and analyzes the driving forces of land use change.

关键词： land use development Liaocheng Prefecture

KoreainvestedenterprisesandthedevelopmentofWeihai

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Journal of Geographical sciences 1998年第2期8卷 28-38页

作者： LI Wenyaninstitute of Geography, chinese academy of sciences, beijing 100101 china

with the implementation of opendoor policy of the ***, Shandong's coastal area, relying on its advantageous location and abundant resources, has become one of the most rapidly developing areas in northern china for ten years or so. In the process of the development of Weihai, Koreainvested enterprises have been playing a more and more important role. Taking Weihai as an example, this paper attempts to make a preliminary study mainly on the relationship between the Korean direct investment and the economic development in china's port cities concerned.

关键词： Koreainvested enterprises sustainable development Weihai china.

Oxygen and hydrogen isotopic compositions of coexistent minerals of the Tasigake alkali granite pluton,northern Xinjiang:constraints upon the cause of ^(18)O-D depletion and the ^(18)O/^(16)O exchange kinetics

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chinese Science Bulletin 1999年第12期44卷 1086-1093页

作者： LIU Wei, ZHAO Zhenhua ZHANG Fuqin Research Center of Mineral Resources Exploration, institute of Geophysics , chinese academy of sciences , beijing 100101, china Guangzhou institute of Geochemistry, chinese academy of sciences , Guangzhou 510640, china Research Center of Mineral Resource Exploration Institute of Geophysics Chinese Academy of Science Beijing China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Oxygen and hydrogen isotopic compositions have been determined of three coexistent mineral triplets of alkali feldspar, quartz, arfvedsonite of 11 samples collected from the Tasigake alkali granite pluton, Ulungur River region, northern Xinjiang. Isotopic exchange with meteoric water during subsolidus cooling caused strong 18O-D depletion and the remarkable nonequilibrium 18O/16O relation between coexistent minerals. 18O/16O exchange kinetic effects of the three minerals are simultaneously and consistently modelled. Exsolution and microtextural reorganization of alkali feldspar, and infiltration of water have been mutually facilitated by each other. Shallow intrusion, and circulation of meteoric water throughout the pluton cool it effectively. As a result, the "heat engine" is rapidly extinguished, and the nonequilibrium 18O/16O relation is frosen.

关键词： 18O-D depletion isotopic exchange kinetics alkali granite Ulungur.

On Post-Shear-Instability in Saturated Soils

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地学前缘 2009年第S1期16卷 262-263页

作者： Xiaobin Lu~1,Xuhui Zhang~2 1.institute of Mechanics,chinese academy of sciences,beijing 100080,china. 2.institute of Mountain Hazard and Environment,chinese academy of sciences,Chengdu china,

The study on the development of shear band is very import since it is the main reason of landslide. According to experimental results,there is only one shear band forming at last when the soil specimen beard shear loa... 详细信息

关键词： shear band landslide finite amplitude disturbances