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Chinese Science Bulletin 2003年第4期48卷 395-400页

作者： MA Zhibang1, LI Hongchun2, XIA Ming1, KU Tehlung2, PENG Zicheng3, CHEN Yushu4 & ZHANG Zhaofeng3 1. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china 2. Department of Earth Sciences, University of Southern California, Los Angeles, CA90089-0740, USA 3. Department of Earth and Space Science, University of Science and Technology of china, Hefei 230026, china 4. beijing Foshan Tourist Service Centre, beijing 101201, china Institute of Geology and Geophysics. Chinese Academy of Sciences Beijing 100029 China

The Mg/Sr ratio in a stalagmite, which is di-rectly proportional to DMg/Ca, the solid-liquid distribution coefficient of Mg, is proposed as a geochemical thermometer to estimate paleotemperature changes. The paleotempera-ture change in eastern beijing over the past 3000 years has been reconstructed by using this thermometer in the stalag-mite ZFFS-1 from Jingdong Cave. The records can be di-vided into two periods: 3000—2000 aBP, cool and wet, the air temperature averaging 9.8℃; and 2000 aBP—present, hot and dry, the air temperature being 1℃ higher than the mean value (11.7℃) of the past 3000 years. During 500—200 aBP, the air temperature was about 1.2℃ lower than that of the present, corresponding to the Little Ice Age in Europe. Like d 18O and d 13C, Mg/Sr (or DMg/Ca) reflects an obviously warming trend of the past 200 years. These results are sup-ported by historic records.

关键词：北京京东溶洞石笋 Mg/Sr记录古气温测年 3000年

Recommendation Method for Contrastive Enhancement of Neighborhood Information

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Computers, Materials & Continua 2024年第1期78卷 453-472页

作者： Hairong Wang beijing Zhou Lisi Zhang He Ma School of Computer Science and Engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-20M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method

Seasonal variations and bioavailability of inorganic phosphorus in soils of Yeyahu Wetland in beijing,china

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International Journal of Sediment Research 2011年第2期26卷 181-192页

作者： ZHANG Jing,LI Min,LIU Shuang,LIU Yujin,ZHANG Liqiang,CAO Qi,and SUN Dezhi 1 Ph.D.student,~ 2 Assoc,Prof,~(3,6) Master,~7 Prof,College of Environmental Science and Engineering,beijing Forestry University,beijing,P.R.china,100083 ~(4,5) Senior Engineer,beijing Yanqing Yeyahu Wetland Nature Reserve,beijing,P.R.china,102101 [a]Ph.D. student College of Environmental Science and Engineering Beijing Forestry University Beijing P.R. China 100083 [b]Assoc. Prof. College of Environmental Science and Engineering Beijing Forestry University Beijing P.R. China 100083 [c]Master College of Environmental Science and Engineering Beijing Forestry University Beijing P.R. China 100083 [f]Master College of Environmental Science and Engineering Beijing Forestry University Beijing P.R. China 100083 [g]Prof. College of Environmental Science and Engineering Beijing Forestry University Beijing P.R. China 100083 [d]Senior Engineer Beijing Yanqing Yeyahu Wetland Nature Reserve Beijing P.R. China 102101 [e]Senior Engineer Beijing Yanqing Yeyahu Wetland Nature Reserve Beijing P.R. China 102101

Phosphorus(P) in soils has an important influence on the development and productivity of wetland. The objective of this study was to investigate the distribution,bioavailability and seasonal variations of inorganic phosphorus(IP) in soils of Yeyahu *** results showed that the concentration of Ca-bound P(Ca-P) remained the main occurrence in all IP fractions despite the season,at the same time the Al-bound P(Al-P) was always the lowest IP fraction despite the ***-P and Fe-bound P (Fe-P) concentration were all reached the highest value in May and the lowest in November,which was opposite to the occluded P(Oc-P) *** notable higher Oc-P concentration in November observed in this study was probably due to the decomposition of plants and the subsequently releasing of oxides to ***-P didn’t change much with season *** P(Ex-P) and Oc-P were all positively correlated with soil moisture content and organic matter content,but Al-P was negatively correlated with these two soil *** a stable form,Ca-P was not associated with soil ***-P,Fe-P and Ca-P might contribute to the storage of P in studied wetland with the principle component analysis *** concentration rank order of the bio-available P in soils was generally as follows:Olsen-P > Algal available P(AAP) > Water soluble P(WSP) > Readily desorbed P(RDP).Olsen-P was positively correlated with Ex-P and Oc-P,and it was thought to be a more suitable indicator for bio-available P in soils.

关键词： Inorganic phosphorus fractions Distribution Bioavailability Seasonal variations

Being the Pioneer of Life Sciences in china——Introduction to beijing Genomics Institute

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Genomics, Proteomics & Bioinformatics 2004年第1期2卷 59-63页

作者： Xin Zhang beijing Genomics Institute, beijing 101300, china. beijing Genomics Institute Beijing 101300 China

The beijing Genomics Institute (BGI) of Chinese Academy of Sciences (CAS) wasofficially founded in December 2003. Its predecessor, beijing Huada Genomics Research Center, haspresented significant contributions to the development of life sciences in china by its excellentscientific innovations and achievements in the last five years. From the participation ofInternational Human Genome Project (HGP) to the independent completion of the whole-genome draft andfine maps of Chinese super hybrid rice genome, from the porcine genome research cooperated withDenmark to the international chicken genome research, and from the silkworm genome projectaccomplished together with The Southwest Agriculture University of china to the great contributionsto the national campaign against SARS, all these facts illustrate that BGI not only has afirst-class scientific research power in the world but also is full of devotion to the flourish ofscience and nation. During these years, we have upheld the strategy of ''Advance through projects,strive for innovation, grow through cooperation'', in the aim of making BGI as one of the pioneers ofCAS climbing the peak of life sciences in the world.

关键词： Chinese Academy of Sciences beijing Genomics Institute innovation life sciences

Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, china

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Science china Earth Sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2 1. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, china 2. Laboratory for Earth Surface Processes, Peking University, beijing 100871, china 1. Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952―2003 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952―1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 150 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92% of total transfer fluxes of HCHs isomers. There were approximately 253t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983, and this percentage may descend to 0.5% after 20 years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials Physics,University of Science and Technology beijing,beijing 100083.china

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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology beijing,beijing,china

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

Community-based prevention and treatment of cardiovascular diseases

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Journal of Geriatric Cardiology 2024年第3期21卷 315-322页

作者： Sheng-Shou HU The Writing Committee of the Report on Cardiovascular Health and Diseases in china Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

The Annual Report on Cardiovascular Health and Diseases in china(2022)intricate landscape of cardiovascular health in *** is the third section of the report with a specific focus on community-based prevention and treatment of cardiovascular diseases(CVD).This section of the report underscores the importance of initiatives outlined in the"Healthy china 2030 Plan,"emphasizing the comprehensive prevention and control strategy for chronic diseases.A key aspect of this plan involves the establishment of national demonstration areas aimed at comprehensive prevention and control of chronic *** 2020,488 such areas had been set up across china,surpassing the initial target and covering a significant proportion of counties and *** report highlights the successful implementation of these strategies in Lishan district,Anshan city,where demonstration areas for comprehensive prevention and control of chronic diseases were launched in *** the course of seven years,the number of healthy units increased substantially,leading to improvements in managing risk factors for CVD among *** reductions in prevalence rates of overweight,obesity,smoking,passive smoking,and drinking were observed,along with the development of healthier behaviors among ***,Qiaokou district in Wuhan City,designated as a national demonstration area in 2014,implemented comprehensive public health promotion ***,special clinics for hypertension intervention were established,contributing to an increase in self-reported rates of hypertension,a slight decrease in prevalence,and a remarkable improvement in the control rate among treated ***,these efforts underscore the effectiveness of community-based approaches in driving positive health outcomes and advancing the comprehensive prevention and control of chronic diseases,particularly cardiovascular diseases,in china.

关键词： prevention district treatment

Cardiovascular Risk Factors in china

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Journal of Geriatric Cardiology 2024年第2期21卷 153-199页

作者： Sheng-Shou HU the Writing Committee of the Report on Cardiovascular Health and Diseases in china Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina 不详

The Annual Report on Cardiovascular Health and Diseases in china(2022) intricate landscape of cardiovascular health in china. This section dissects cardiovascular risk factors in china which including hypertension, dyslipidemia, diabetes mellitus, chronic kidney disease, metabolic syndrome and air pollution. Hypertension prevalence has steadily increased in china,with efforts to control it facing challenges in achieving optimal rates, especially in rural areas. Interventions like salt substitutes and intensive blood pressure control show promise but need improvement. Abnormal lipid levels, indicative of dyslipidemia,have risen significantly, posing a risk for cardiovascular diseases. Despite efforts, many patients struggle to achieve target lipid levels, necessitating improved treatment strategies. Both type 1 and type 2 diabetes mellitus affect millions of adults in china,with long-term complications adding to the disease burden. Early intervention and effective management are crucial to mitigate its impact. Prevalent among older adults, chronic kidney disease is associated with diabetes mellitus, hypertension, and cardiovascular diseases, necessitating comprehensive management approaches. The prevalence of metabolic syndrome, characterized by a cluster of risk factors, has increased in both adults and adolescents, calling for lifestyle modifications and public health interventions. Ambient and household air pollution remain significant environmental risk factors, despite some improvements in air quality. Continued efforts to reduce emissions are essential for mitigating associated health risks. Addressing these risk factors requires a multifaceted approach, including public health initiatives, policy interventions, and individual-level strategies to promote healthy lifestyles and reduce environmental exposures. Surveillance and research efforts are crucial for monitoring trends and developing effective strategies to lessen the burden of cardiovascular diseases in

关键词： landscape adding spite

Heart failure in china:epidemiology and current management

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Journal of Geriatric Cardiology 2024年第6期21卷 631-641页

The Annual Report on Cardiovascular Health and Diseases in china(2022)intricate landscape of cardiovascularhealth in *** connection with the previous section,this sixth section of the report offers a comprehensive analysis of heart failure(HF)in *** is one of the most important cardiovascular disease in the 21st *** mortality is equivalent to that of *** is an important public health problem that seriously affects the health of Chinese *** recent years,with the deepeningof understanding,the change of treatment principles,the innovation of treatment methods and the update of treatment guidelines,the in-hospital mortality of HF patients has declined,and the long-term prognosis is also ***,there are stilldifferences in the management level of HF among different hospitals in *** to improve the standardized diagnosis andtreatment level of HF in china remains an important challenge.

关键词： epidemiology diagnosis treatment

SHRIMP ages of detrital zircons from the Changcheng System in the Ming Tombs area,beijing:Constraints on the protolith nature and maximum depositional age of the Mesoproterozoic cover of the North china Craton

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Chinese Science Bulletin 2003年第22期48卷 2500-2506页

作者： WAN Yusheng1,2, ZHANG Qiaoda1 & SONG Tianrui1 1. Institute of Geology, Chinese Academy of Geological Sciences, beijing 100037, china 2. beijing SHRIMP Laboratory, beijing 100037, china Correspondence should be addressed to Wan Yusheng (e-mail: wanyusheng@***) Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

The Mesoproterozoic Changcheng System is widely distributed in the North china Craton. Determining its time of deposition and sources is important to understand the Precambrian crustal evolution of the North china Craton. This paper suggests age distribution patterns for detrital zircons from clastic sediments of the Changcheng System in the Ming Tombs area, beijing. Samples of feldspar-bearing sandstone (CHc-2) and pure sandstone (CHc-9) were collected from the Changzhougou Formation, which constitutes the basal part of the Changcheng System. Detrital zircons show an age range from 2.35 to 2.60 Ga. However, sample CHc-9 in the upper Changzhougou Formation also contains some zircons with ages of 1.9-1.8 Ga and 2.3-2.1 Ga. The age patterns lead to the following conclusions: (1) Most of the detrital material came from a source area composed predominantly of ~2.5 Ga continental crust of the North china Craton; (2) 1.9-1.8 Ga reflects the age record of Palaeoproterozoic continent-continent collisional event in the North china Craton; and (3) the oldest age for deposition of the Changcheng System is 1.8 Ga.

关键词：锆石原岩中国北部地区地壳演变