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Applying Machine Learning Approach to Explore Childhood Circumstances and Self-Rated Health in Old Age-China and the US,2.2.-2.2.

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China CDC weekly 2024年第11期6卷 213-218,I0008-I0013页

作者： Shutong Huo Derek Feng Thomas M.Gill xi Chen Department of Health Society&BehaviorPublic HealthUniversity of CaliforniaIrvineCAUSA Department of Statistics and Data Science Yale UniversityNew HavenCTUS Department of Internal Medicine Yale School of MedicineNew HavenCTUS Department of Health Policy and Management Yale School of Public HealthNew HavenCTUS Department of Economics Yale UniversityNew HavenCTUS.

Introduction:Childhood circumstances impact senior health,prompting the introduction of machine learning methods to assess their individual and collective contributions to senior ***:Using health and retirement study(HRS)and China Health and Retirement Longitudinal Study(CHARLS),we analyzed 2.434 American and 5.612.chinese participants aged 60 and *** inference trees and forests were employed to estimate the influence of childhood circumstances on self-rated health(SRH).Results:The conventional method estimated higher inequality of opportunity(IOP)values in both China(0.039,accounting for 2..67%of the total Gini coefficient 0.172.and the US(0.067,accounting for 35.08%of the total Gini coefficient 0.191).In contrast,the conditional inference tree yielded lower estimates(China:0.02.,accounting for 12.79%of 0.172.US:0.044,accounting for 2..04%of 0.191),as did the forest(China:0.035.accounting for 2..35.of 0.172.US:0.05.,accounting for 2..2.%of 0.191).Childhood health,financial status,and regional differences were key determinants of senior *** conditional inference forest consistently outperformed others in predictive accuracy,as demonstrated by lower out-of-sample mean squared error(MSE).Discussion:The findings emphasize the need for early-life interventions to promote health equity in aging *** learning showcases the potential in identifying contributing factors.

关键词： collective inequality estimates

Synthesis and reactivity of cobalt dinitrogen complex supported by nonsymmetrical pincer ligand

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chinese Chemical Letters 2024年第7期35卷 259-263页

作者： Yuanjin Chen xianghui Shi Dajiang Huang Junnian Wei Zhenfeng xi Beijing National Laboratory for Molecular sciences(BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of ChemistryPeking UniversityBeijing 100871China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai 200032China

A nonsymmetrical PNN pincer ligand[6-(^(t)Bu_(2.PNH)C_(5.H_(4)N-2.(3-Mes)C_(3)H_(2.N_(2.]and its corresponding cobalt-N_(2.complex were synthesized and *** the stoichiometric reaction of the PNN ligand lithium salt with CoCl_(2.,the complex 3,(PNN)CoCl,was ***,reduction of 3 with NaBHEt3under a dinitrogen atmosphere yielded complex 5.(PNN)Co(Ⅰ)(η^(1)-N_(2.).Single-crystal X-ray analysis,IR spectrum,and DFT calculations revealed that the dinitrogen in 5.was only weakly reduced by the cobalt *** reactions of 5.with carbon monoxide and 2.6-dimethylphenyl isocyanide gave carbonyl and isocyanide complexes 6 and 7 with the release of N_(2.,***,these cobalt complexes,especially complex 5.demonstrated the capacity to convert dinitrogen to N(TMS)_(3)with moderate efficiency.

关键词： Dinitrogen fixation Dinitrogen transformation Nonsymmetrical pincer ligand Cobalt complex Catalytic silylamine formation

Gas formation mechanism of marine carbonate source rocks in China

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Science China earth sciences 2005年第4期48卷 441-453页

作者： ZHAO Wenzhi1, WANG Zhaoyun1, HE Haiqing2. ZHANG Mingjie3, WANG Hongjun1, WANG Yunpeng4 & QIN Yong5.1. Research institute of Petroleum Exploration & Development, PetroChina, Beijing 100083, China 2. PetroChina Exploration & Production, Beijing 100011, China 3. Department of Geology, Lanzhou University, Lanzhou 730000, China 4. Guangzhou Geochemical institute,{2., Guangzhou 5.0640, China 5. China University of Mining and Technology, Xuzhou 2.1000, China 1. Research institute of Petroleum Exploration & Development 100083 PetroChinaBeijin China 2. PetroChina Exploration & Production 100011 Beijing China 3. Department of Geology Lanzhou University 730000 Lanzhou China 4. Guangzhou Geochemical institute Chinese Academy of Sciences 510640 Guangzhou China 5. China University of Mining and Technology 221000 Xuzhou China

By breaking through the conventional ideology on the study of gas-formation mechanism of source rocks which focused on merely the characteristics of source rocks them- selves, and based on the development and distribution characteristics of marine carbonate source rocks in the medium-to-bottom parts of the chinese superimposed sedimentary basins as well as various processes in the course of gas generation and reservoir forming, the complex hydrocarbon-generating model of carbonates is established. Such a model concerns not only the “three-stage” gas formation characteristics of carbonates, but also the gas generation process due to a thermal cracking of oil and the re-generation process of gas from heated secondary organic matters during the gas-generation and reservoir-forming course. The high-quality hy- drocarbon generating matter of marine carbonate source rocks determined a high gas-oil ratio and tended to form paleo-oil-reservoirs, representing an enrichment process of organic matters. The thermal cracking of oil in palaeo-oil-reservoirs is an important means for the effective forma- tion of gas reservoirs. The secondary organic matters in carbonate reservoirs may regenerate gas after a secondary deep burial, thus becoming an effective gas source.

关键词： carbonate, three-stage hydrocarbon generation, inhibitive effect of maturity, oil-cracking gas, second-ary asphalt gas.

Stereoselective Synthesis of (6R)-6-(5.Methyl-2.furyl)-2.oxocyclohexanecarboxyl-10', 2.-Sultam

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chinese Chemical Letters 1999年第9期10卷 733-734页

作者： xi Lu WANG You Hong HU Li Gong OU Dong Lu BAI(Shanghai institute of Materia Medica. chinese academy of sciences, Shanghai 2.0031) chinese Acad Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China

Stereoselective synthesis of sultam 8 was reported. The overall yield in a scLluence of 4steps is 2..5..

关键词： Stcreoselective. synthesis. sultam. conjugated addition.

Chronological record of the Early Mesozoic underplating in the northern margin of North China—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in Natural Science:Materials International 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2.*) Zhang Hongfu~2.Liu xiaoming~3 Li Zhitong~4 (1.School of earth and Space sciences,Peking University,Beijing 100871,China 2.{2. of Geology and Geophysics and Key Laboratory of Mineral Resources,chinese academy of sciences,Beijing 10002.,China 3.Key Laboratory of Continental Dynamics,Northwestern University,xi'an 710069,China 4.{2. of Geology and Mineral Resources of Shenyang,Shenyang 110032.China) [a]School of earth and Space sciences Peking University Beijing China [b]Laboratory of Mineral Resources Chinese Academy of Sciences Institute of Geology and Continental Dynamics Beijing China [c]Key Laboratory of Continental Dynamics Northwestern university Xi'an China [d]institute of Geology and Mineral Resources of Shenyang Shenyang China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 2.4 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North China Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite

The great Ordovician radiation of marine life: Examples from South China

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Progress in Natural Science:Materials International 2008年第1期18卷 1-12页

作者： Renbin Zhan a,*, Jisuo Jin b, Yuandong Zhang a, Wenwei Yuan a a State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing institute of Geology and Palaeontology, chinese academy of sciences, Nanjing 2.0008, China b Department of {2. sciences, University of Western Ontario, London Ont., Canada N6A 5.7 State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China Department of earth sciences University of Western Ontario London Ont. Canada N6A 5B7

The Ordovician radiation is the earliest and most important biodiversification event in the evolution of the Paleozoic Evolutionary Fauna (PEF), when the basic framework of PEF was established. The radiation underwent a gradual, protracted process spanning more than 40 million years and was marked by several diversity maxima of the PEF. Case studies conducted on the Upper Yangtze Platform (South China Palaeoplate) showed that the Ordovician radiation was characterized by drastic increases in a- and b-diversity in various groups of organisms. During the radiation, brachiopods, trilobites, and graptolites of the PEF became more diverse to dominate over the Cambrian Evolutionary Fauna (CEF) in all marine environments. At either global or regional scales, however, the Ordovician radiation was highly heterogeneous in time and space, and the rate and pattern of radiation exhibited by difierent major fossil groups were also variable.

关键词： Ordovician radiation Paleozoic Evolutionary Fauna a-diversity b-diversity Upper Yangtze Platform

Experimental studies on silicate structures of basaltic glasses quenched at 1 65.℃ and 1—3.5.GPa

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chinese Science Bulletin 1999年第5期44卷 461-466页

作者： ZHUWeiguo, xiEHongsen, XU Jian, HOUWei, ZHANG Yueming, QUO Jie and XU Zhuming earth ’s Interior Material Laboratory, institute of Geochemistry,{2., Guiyang 5.0002. China institute of earth Science, Academia Sinica , Taibei, Taiwan, China earth’s Interior Material Laboratory Institute of Geochemistry Chinese Academy of Sciences Guiyang China institute of earth Science Academia Snica Taibei Taiwan China

A series of melting experiments was carried out at 1 65.℃ and 1.00-3.00 GPa using alkaline basalt as starting material. The compositions of quenched basaltic glasses in the products were detected by electron micro probe. Their CIPW norms were calculated and their refractive indices were determined by the oil-infused method. The Raman spectrum of the quenched basaltic glasses indicates that their main structural species are monomer [SiO4]4-, chain [Si2.6]4- and sheet [Si2.5.2. . The relationship at the same temperature between the proportions of integrated areas of structural species, and compositions and pressures was discussed.

关键词： quenched basaltic glass structure of melt Raman spectrum.

Assessing the performance of magnetopause models based on THEMIS data

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earth and Planetary Physics 2024年第5期8卷 776-786页

作者： Yang Lin JianYong Lu BaoHang Qu xi Wang institute of Space Weather School of Atmospheric PhysicsNanjing University of Information Science & Technology

The magnetopause is the boundary between the earth's magnetic field and the interplanetary magnetic field（IMF）,located where the supersonic solar wind and magnetospheric pressure are in *** empirical models and global magnetohydrodynamic simulations have been used to define the magnetopause,each of these has *** this work,we use15.years of magnetopause crossing data from the THEMIS（Time History of Events and Macroscale Interactions during Substorms）spacecraft and their corresponding solar wind parameters to investigate under which solar wind conditions these models predict more *** analyze the pattern of large errors in the extensively used magnetopause model and show the specific solar wind parameters,such as components of the IMF,density,velocity,temperature,and others that produce these *** is shown that（1） the model error increases notably with increasing solar wind velocity,decreasing proton density,and increasing temperature;（2. when the cone angle becomes smaller or|Bx|is larger,the Shue98 model errors increase,which might be caused by the magnetic reconnection on the dayside magnetopause;（3） when|By|is large,the error of the model is large,which may be caused by the east–west asymmetry of the magnetopause due to magnetic reconnection;（4） when Bzis southward,the error of the model is larger;and（5. the error is larger for positive dipole tilt than for negative dipole tilt and increases with an increasing dipole tilt ***,the global simulation model b Liu ZQ et al.（2.15. shows a substantial improvement in prediction accuracy when IMF Bx,By,or the dipole tilt cannot be *** result can help us choose a more accurate model for forecasting the magnetopause under different solar wind conditions.

关键词： magnetopause empirical model global magnetohydrodynamic simulation THEMIS solar wind parameters

Source mechanism of strong aftershocks (M_s≥5.6) of the 2.08/05.12.Wenchuan earthquake and the implication for seismotectonics

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Science China earth sciences 2009年第6期52卷 739-753页

Dozens of >M5. hundreds of >M4, and much more >M3 aftershocks occurred after the 2.08/05.12.Wenchuan earthquake, which were well recorded by permanent and portable seismic stations. After relocated with P arrival, the >M3 aftershocks show two trends of distribution, with most of the aftershocks located along the north-east strike consistent with Longmenshan fault system, yet there is a north-west trend around the epicenter. It seems that substantially more aftershocks occur in regions with crystalline bedrocks. Then we collected waveform data from National Digital Seismograph Network and regional seismograph network of China, and employed 'Cut and Paste' method to obtain focal mechanisms and depths of the big aftershocks (M≥5.6). While most of those aftershocks show thrust mechanism, there are some strike slip earthquakes in the northern-most end of the rupture. Focal mechanisms show that the events located on the southern part of central Beichuan-Yingxiu Fault (BY) are mainly thrust earthquakes, which is consistent with initial mechanism of the main shock rupture. In the north part the aftershocks along the BY are also dominated by thrust slip, which is quite different from the right slip rupture of the main shock. Around Qingchuan-Pingwu Fault, the focal mechanisms are dominated by right-slip rupture with large depths (~18 km). So we suspected that in the north part the main shock might rupture on two faults: Beichuan Fault and Qingchuan-Pingwu Fault. The complex pattern of aftershock mechanisms argues for presence of a complicated fault system in the Longmenshan area.

关键词： focal mechanism seismotectonics Wenchuan earthquake cut and paste.