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Tracing of natural gas migration by light hydrocarbons:A case study of the Dongsheng gas field in the Ordos Basin,NW China
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作者 WU Xiaoqi NI Chunhua +3 位作者 MA Liangbang WANG Fubin JIA Huichong WANG Ping 《Petroleum Exploration and Development》 SCIE 2024年第2期307-319,共13页
Based on the analysis of light hydrocarbon compositions of natural gas and regional comparison in combination with the chemical components and carbon isotopic compositions of methane,the indication of geochemical char... Based on the analysis of light hydrocarbon compositions of natural gas and regional comparison in combination with the chemical components and carbon isotopic compositions of methane,the indication of geochemical characteristics of light hydrocarbons on the migration features,dissolution and escape of natural gas from the Dongsheng gas field in the Ordos Basin is revealed,and the effect of migration on specific light hydrocarbon indexes is further discussed.The study indicates that,natural gas from the Lower Shihezi Formation(Pix)in the Dongsheng gas field displays higher iso-C5-7contents than n-C5-7contents,and the C6-7light hydrocarbons are composed of paraffins with extremely low aromatic contents(<0.4%),whereas the C7light hydrocarbons are dominated by methylcyclohexane,suggesting the characteristics of coal-derived gas with the influence by secondary alterations such as dissolution.The natural gas from the Dongsheng gas field has experienced free-phase migration from south to north and different degrees of dissolution after charging,and the gas in the Shiguhao area to the north of the Borjianghaizi fault has experienced apparent diffusion loss after accumulation.Long-distance migration in free phase results in the decrease of the relative contents of the methylcyclohexane in C7 light hydrocarbons and the toluene/n-heptane ratio,as well as the increase of the n-heptane/methylcyclohexane ratio and heptane values.The dissolution causes the increase of isoheptane values of the light hydrocarbons,whereas the diffusion loss of natural gas in the Shiguhao area results in the increase of n-C5-7contents compared to the iso-C5-7contents. 展开更多
关键词 Ordos Basin Dongsheng gas field Permian Lower Shihezi Formation light hydrocarbon compounds MATURITY natural gas origin migration phase state diffusion loss
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Survivors of COVID-19 exhibit altered amplitudes of low frequency fluctuation in the brain: a resting-state functional magnetic resonance imaging study at 1-year follow-up 被引量:2
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作者 Yan-Yao Du Wei Zhao +13 位作者 Xiang-Lin Zhou Mu Zeng Dan-Hui Yang Xing-Zhi Xie Si-Hong Huang Ying-Jia Jiang Wen-Han Yang Hu Guo Hui Sun Ji-Yang Liu Ping Liu Zhi-Guo Zhou Hong Luo Jun Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第7期1576-1581,共6页
Although some short-term follow-up studies have found that individuals recovering from coronavirus disease 2019(COVID-19)exhibit anxiety,depression,and altered brain microstructure,their long-term physical problems,ne... Although some short-term follow-up studies have found that individuals recovering from coronavirus disease 2019(COVID-19)exhibit anxiety,depression,and altered brain microstructure,their long-term physical problems,neuropsychiatric sequelae,and changes in brain function remain unknown.This observational cohort study collected 1-year follow-up data from 22 patients who had been hospitalized with COVID-19(8 males and 11 females,aged 54.2±8.7 years).Fatigue and myalgia were persistent symptoms at the 1-year follow-up.The resting state functional magnetic resonance imaging revealed that compared with 29 healthy controls(7 males and 18 females,aged 50.5±11.6 years),COVID-19 survivors had greatly increased amplitude of low-frequency fluctuation(ALFF)values in the left precentral gyrus,middle frontal gyrus,inferior frontal gyrus of operculum,inferior frontal gyrus of triangle,insula,hippocampus,parahippocampal gyrus,fusiform gyrus,postcentral gyrus,inferior parietal angular gyrus,supramarginal gyrus,angular gyrus,thalamus,middle temporal gyrus,inferior temporal gyrus,caudate,and putamen.ALFF values in the left caudate of the COVID-19 survivors were positively correlated with their Athens Insomnia Scale scores,and those in the left precentral gyrus were positively correlated with neutrophil count during hospitalization.The long-term follow-up results suggest that the ALFF in brain regions related to mood and sleep regulation were altered in COVID-19 survivors.This can help us understand the neurobiological mechanisms of COVID-19-related neuropsychiatric sequelae.This study was approved by the Ethics Committee of the Second Xiangya Hospital of Central South University(approval No.2020 S004)on March 19,2020. 展开更多
关键词 amplitude of low-frequency fluctuation clinical study coronavirus disease 2019 FOLLOW-UP functional magnetic resonance imaging long-term physical consequences neuropsychiatric sequelae resting‐state function
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A Comparative Study for the Development of Coal-to-Liquids Industries in China, South Africa and United States
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作者 Yiming Li Changqing Li 《Green and Sustainable Chemistry》 2019年第3期85-93,共9页
Many energy consuming countries have carried out research, development, demonstration, planning and deployment of coal-to-liquids (CTL) because of its ability to replace oil imports by converting coal resources into f... Many energy consuming countries have carried out research, development, demonstration, planning and deployment of coal-to-liquids (CTL) because of its ability to replace oil imports by converting coal resources into fuel. Among them, China and South Africa successfully had their CTL technology industrialized, while the United States did not. To understand the differences in the industrial development level, a comparative study is necessary. This paper compares the history, driver and policy of CTL industry in China, South Africa and United States, collates and discloses numbers of industry details for the first time. We figure out that the motivation, top level planning and policy consistency are the key indicators of the difference on the industrial development level. Among them, the key to the success of CTL industrialization in China and South Africa is the government’s strong and stable determination to improve energy security, which provides a stable top-level planning and robust policy support. The failure of CTL in United States is caused by the shift of policy attention after its energy security situation improved. 展开更多
关键词 Coal-to-Liquids Comparative study China UNITED stateS SOUTH AFRICA
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Functions of Rhetoric and Social Science Origins in Communication Study—Based on Boxing Plato’s Shadow:An Introduction to the Study of Human Communication
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作者 WANG Hai HUANG Dai-ming 《Journal of Literature and Art Studies》 2020年第3期255-270,共16页
With the development of the rhetoric study from the origins in ancient Athens and The Rhetoric of Aristotle to the formation of modern Communication Study at the beginning of the twentieth century,the Rhetoric Study c... With the development of the rhetoric study from the origins in ancient Athens and The Rhetoric of Aristotle to the formation of modern Communication Study at the beginning of the twentieth century,the Rhetoric Study changed in dynamic and its concepts and theories merged and formed the foundations of Communication Study which focused on personal communication and speech rhetoric skills at that time.At the beginning of the twentieth century,although the Neo-Aristotelian rhetorical scholars from classic rhetoric approach created methodologies and enriched the content of Communication Study under the influence of humanistic study and social science study,but the Communication discipline was still in the embarrassing position.During World War I and World War II,most scholars with backgrounds of social science,history and anthropology carried out the studies of propaganda wars and the message disseminating,and explored the military powers and governments’access to the media and developed serial communication modes from the social science perspective,which laid the foundation for Communication discipline in the academic field.The author analyzed the Rhetoric and Social Science origins of Communication study in Boxing Plato’s Shadow:an Introduction to the Study of Human Communication,which is beneficial and helpful to understand the academic origins of Communication study and its cross-disciplined and embarrassing positions. 展开更多
关键词 the origins of COMMUNICATION study RHETORIC origins social science origins BOXING Plato’s SHADOW an INTRODUCTION to the study of human COMMUNICATION
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Original State of Grotto Eaves of the Daxiang Mountain Grottoes of Gangu County
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作者 YE Minghui MENG Xiangwu 《Journal of Landscape Research》 2015年第6期8-10,共3页
Located in the east of Gansu Province, Gangu County in Tianshui City is the only way that people went to the Central Plains from the western regions in ancient times, and it's also an important node of the Grotto ... Located in the east of Gansu Province, Gangu County in Tianshui City is the only way that people went to the Central Plains from the western regions in ancient times, and it's also an important node of the Grotto Culture Corridor of the Silk Road. Daxiang Mountain Giant Buddha Grottoes is the landmark of Gangu County. The giant Buddha statue stands among cliffs 200 meters high above the ground, and it is the second largest stone-base clay-sculpture Buddha in China. After going through thousands of years, the Giant Buddha Grottoes needs effective and scientific protection. This article was originated from the actual project—The Research on the Construction Technology of Wooden-structure Grotto Eaves in the Daxiang Mountain. This article f inished the rebuilding plan for the Buddha Grotto Eaves on the basis of analyzing historical documents, hole traces, morphological evolution and image demonstration. 展开更多
关键词 Daxiang Mountain Grotto Grotto eaves original state of the building
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AB INITIO STUDY OF LOW-LYING ELECTRONIC STATES OF THE AsH_2 RADICAL
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作者 Zheng Li CAI Department of Chemistry,East China Instit of Technology,Nanjing 210014 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期239-242,共4页
The equilibrium geometries,excitation energies,force constants and vibrational frequencies for the low-ly- ing electronic states X ~2B_1,~2A_1,~2B_2 and ~2A_2 of the AsH_2 radical have been calculated at the MRSDCI le... The equilibrium geometries,excitation energies,force constants and vibrational frequencies for the low-ly- ing electronic states X ~2B_1,~2A_1,~2B_2 and ~2A_2 of the AsH_2 radical have been calculated at the MRSDCI level with a 3-21G~* basis set.Our calculated geometries,excitation enegies and vibional frequencies for the X ~2B_1 and ~2A_1 states are in good agreement with available experimental data.The electronic transition dipole mo- ments,oscillator strengths for the ~2A_1→X ~2B_1 and ~2A_2→X ~2B_1 transitions,radiative lifetimes for the ~2A_1 and ~2A_2 states are calculated based on the MRSDC^1 wavefunctions,predicting results in reasonable agreement with available experiment. 展开更多
关键词 As BI AI NATURE AB INITIO study of LOW-LYING ELECTRONIC stateS of the AsH2 RADICAL
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A POST-SCF STUDY ON THE EXCITED STATES OF MgH_2
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作者 Jie YANG Guo Sen YAN An Min TIAN 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第2期171-174,共4页
The calculations on the ground state and two excited states3B2,BIB2 of MgH2 system are carried out by using (Second Order Configuration Interaction)method.For each state,the electronic structure and related propertie... The calculations on the ground state and two excited states3B2,BIB2 of MgH2 system are carried out by using (Second Order Configuration Interaction)method.For each state,the electronic structure and related properties are investigated,The vibration and localization analyses are also performed.The reasonable explanations of bending geometries for the excited states are given. 展开更多
关键词 SCF A POST-SCF study ON the EXCITED stateS of MgH2 HG
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A SCF-SOCI STUDY ON THE LOW-LYING STATES OF H_3^+
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作者 Jie YANG Guo Sen YAN An Min TIAN 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第1期93-94,共2页
The ground state and three low-lying states of the H_3^+ are determined by SOCI(Second Order Configuration Interaction) calculations. The results indicate that the ~3Σ_u^+ state of H_3^+ 3 is a bound state, but ~1A_1... The ground state and three low-lying states of the H_3^+ are determined by SOCI(Second Order Configuration Interaction) calculations. The results indicate that the ~3Σ_u^+ state of H_3^+ 3 is a bound state, but ~1A_1 and ~3A_1 states are not stable, each of them will dissociate into H_2^+ and H atom. The SOCI energy -1.1144065au at an equidistant nuclear separation of 1.296A is in good agreement with the lowest value reported so far. 展开更多
关键词 SCF A SCF-SOCI study ON the LOW-LYING stateS of H3
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THEORETICAL STUDY ON THE EXCITED STATES AND STABILITIES OF B_3, B_3^- AND B_3^+
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作者 Ze Xing CAO, An Min TIAN, Guo Ming LIANG, and Guo Sen YAN Department of Chemistry, Sichuan University, Chengdu 610064 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第1期75-78,共4页
The geometries and vibrational frequencies of the ground and low-lying excited states for B_3, B_3^- and B_3^+ are determined with the energy gradient method using the polarized double-zeta(6-31G*) basis set. The stab... The geometries and vibrational frequencies of the ground and low-lying excited states for B_3, B_3^- and B_3^+ are determined with the energy gradient method using the polarized double-zeta(6-31G*) basis set. The stabilities for the states of B_3,B_3^- and B_3^+ have been investigated based on the vibrational analysis. The correlation energy obtained for each state is considered with the configuration interaction (CISD+Q) technique. B_3 and B_3^+ have stable equilateral triangle geometry, while B_3^- has stable equilateral triangle, isosceles triangle and linear geometries. The Jahn-Teller distortion for a ~3E' state of B_3^- in D_(3h) symmetry is also discussed. 展开更多
关键词 AND B3 B3 theORETICAL study ON the EXCITED stateS AND STABILITIES of B3 功山
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CAS-MCSCF Study on the Ground State of the Ditungsten Molecule(W_2)
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作者 GUO Liang LI Xue Yan TU Shu Shan DAI(Department of Chemistry, Yunnan University, Kunming. Yunnan 650091) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第4期347-350,共4页
Complete active space multiconfiguration self-consisten-field (CAS-MCSCF)calculations are carried out on the ground stae() of W_2. The spectroscopic properties(Re=2.078A. De=4.224eV and ωe=304.3cm-1) and the poential... Complete active space multiconfiguration self-consisten-field (CAS-MCSCF)calculations are carried out on the ground stae() of W_2. The spectroscopic properties(Re=2.078A. De=4.224eV and ωe=304.3cm-1) and the poential energy curve of the state are reported. The calculations predict the W-W bond order of 5.02. 展开更多
关键词 CAS-MCSCF study on the Ground state of the Ditungsten Molecule W2
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THE APPLICATION OF MICROELECTRODE TO THE STUDY OF MULTISTEP ELECTRODE PROCESSES UNDER STEADY STATE CONDITIONS PART I EE MECHANISM
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作者 Qian Kun ZHUANG Hong Yuan CHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第3期217-218,共2页
Under steady-state conditions, the general currents of EE reactions at disk,hemispherical and spherical microelectrodes are derived.From these equations, some electrode reaction parameters can be very simply obtained.
关键词 EE the APPLICATION of MICROELECTRODE TO the study of MULTISTEP ELECTRODE PROCESSES UNDER STEADY state CONDITIONS PART I EE MECHANISM
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China's study on coal mining beneath surface buildings——state-of-the-art and developing trend
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作者 TENG Yong-hai~(1, 2), WANG Jin-zhuang~1 (1. China Institute of Mining Technology Beijing Campus, Beijing 100083, China 2. China Coal Research Institute Tangshan Branch, Tangshan 063012, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期13-16,共4页
Extensive coal deposits are sterilized beneath surface buildings in China. The paper elaborates on the present status of the study on mining beneath surface buildings from several aspects involving the techniques for ... Extensive coal deposits are sterilized beneath surface buildings in China. The paper elaborates on the present status of the study on mining beneath surface buildings from several aspects involving the techniques for reducing ground subsidence and deformation and the measures for protecting buildings. Following that, it is pointed out that, in the future, more efforts should be directed forwards the following aspects: the laws governing the ground movement; the techniques for constructing anti-deformation buildings; coal-bed gasification and protection of buildings; grouting of the overlying strata with bed separation phenomena; and the method for evaluating the stability of the ground above a worked-out area. 展开更多
关键词 MINING BENEATH buildings state-of-the-ART of study developing TREND
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Study on the Rights to Subsistence and Development with Reference to the Origin of the Universal Declaration of Human Rights
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作者 李君如 Hu Liang(译) 《The Journal of Human Rights》 2018年第5期461-464,共4页
I.The History of the Drafting of the Universal Declaration of Human Rights:the Position and Role of the UN Economic and Social Council and the General Assembly of the United Nations should not be Ignored The reason fo... I.The History of the Drafting of the Universal Declaration of Human Rights:the Position and Role of the UN Economic and Social Council and the General Assembly of the United Nations should not be Ignored The reason for me to use the term "source"in the discussion on the right to subsistence 展开更多
关键词 UN study on the Rights to Subsistence and Development with Reference to the origin of the Universal Declaration of Human Rights
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Racial differences in the anatomical distribution of colorectal cancer:a study of differences between American and Chinese patients 被引量:30
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作者 San-HuaQing Kai-YunRao +1 位作者 Hui-YongJiang StevenD.Wexner 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第4期721-725,共5页
AIM: To compare the racial differences of anatomical distribution of colorectal cancer (CRC) and determine the association of age, gender and time with anatomical distribution between patients from America (white) and... AIM: To compare the racial differences of anatomical distribution of colorectal cancer (CRC) and determine the association of age, gender and time with anatomical distribution between patients from America (white) and China (oriental).METHODS: Data was collected from 690 consecutive patients in Cleveland Clinic Florida, U.S.A. and 870consecutive patients in Nan Fang Hospital affiliated to the First Military Medical University, China over the past 11years from 1990 to 2000. All patients had colorectal adenocarcinoma diagnosed by histology and underwent surgery.RESULTS: The anatomical subsite distribution of tumor,age and gender were significantly different between white and oriental patients. Lesions in the proximal colon (P<0.001) were found in 36.3 % of white vs 26.0 % of oriental patients and cancers located in the distal colon and rectum in 63.7 % of white and 74 % of oriental patients (P<0.001). There was a trend towards the redistribution from distal colon and rectum to proximal colon in white males over time, especially in older patients (>80 years).No significant change of anatomical distribution occurred in white women and Oriental patients. The mean age at diagnosis was 69.0 years in white patients and 48.3 years in Oriental patients (P<0.001).CONCLUSION: This is the first study comparing the anatomical distribution of colorectal cancers in whites and Chinese patients. White Americans have a higher risk of proximal CRC and this risk increased with time. The proportion of white males with CRC also increased with time.Chinese patients were more likely to have distal CRC and developed the disease at a significantly earlier age than white patients. These findings have enhanced our understanding of the disease process of colorectal cancer in these two races. 展开更多
关键词 Asian Continental Ancestry Group European Continental Ancestry Group ADENOCARCINOMA ADULT Age Distribution Aged Aged 80 and over China Colonic Neoplasms Colorectal Neoplasms Comparative study Female Humans Male Middle Aged Rectal Neoplasms Retrospective Studies United states
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DFT study on mechanism of the classical Biginelli reaction 被引量:2
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作者 Jin Guang Ma Ji Ming Zhang Hai Hui Jiang Wan Yong Ma Jian Hua Zhou 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第3期375-378,共4页
The condensation of benzaldehyde, urea, and ethyl acetoacetate according to the procedure described by Biginelli was investigated at the B3LYP/6-31G(d), B3LYP/6-31 +G(d,p), and B3LYP/6-311+G(3df,2p)//B3LYP/6-3... The condensation of benzaldehyde, urea, and ethyl acetoacetate according to the procedure described by Biginelli was investigated at the B3LYP/6-31G(d), B3LYP/6-31 +G(d,p), and B3LYP/6-311+G(3df,2p)//B3LYP/6-31+G(d,p) levels to explore the reaction mechanism. According to the mechanism proposed by Kappe, structures of five intermediates were optimized and four transition states were found. The calculation results proved that the mechanism proposed by Kappe is right. 展开更多
关键词 Biginelli reaction DIHYDROPYRIMIDINES Transition state DFT study
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To Knowledge of the Origin of the Brain Mental Activity 被引量:1
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作者 Evgene A. Yumatov 《World Journal of Neuroscience》 2014年第2期170-182,共13页
This paper is devoted towards the origin of a human subjective state, and we present a methodology for studying the origin of brain activity. We were first to reveal that the subjective states of a human being can be ... This paper is devoted towards the origin of a human subjective state, and we present a methodology for studying the origin of brain activity. We were first to reveal that the subjective states of a human being can be subjected to an objective remote registration. Recently we have established the existence of the so-called “psychogenic field”, which reflects the subjective state of human brain. The subjective state of a human being was shown to affect remotely the physicochemical properties of the blood. The interaction of neurophysiological and subjective processes is described in the context of systemic organization of a goal-directed behavior. An original schematic diagram is presented to describe the formation of a subjective brain state. This approach is based on the feedback influence of a psychogenic field on neuronal molecular processes (self-induction in the brain). We propose a paradigm for the origin of a subjective state and possible existence of physical phenomena and brain fields, which are unique for the active brain. 展开更多
关键词 MENTALITY Consciousness SUBJECTIVE state BRAIN PSYCHOGENIC Field Paradigm of a SUBJECTIVE state origin
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Challenges of agriculture and food systems issues in China and the United States 被引量:2
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作者 Gregory Veeck Ann Veeck Hongyan Yu 《Geography and Sustainability》 2020年第2期109-117,共9页
China and the United States are the two most significant nations in the contemporary global food and agricultural network.In addition,they are two of the most important innovators with respect to the development of ne... China and the United States are the two most significant nations in the contemporary global food and agricultural network.In addition,they are two of the most important innovators with respect to the development of new crop varieties,agro-technologies,farm products,markets and consumer issues,such as consumer resistance to genetically modified foods,among others.In the face of an ever-complex web of interactions,technologies and products among producers and consumers in both nations,there are far more structural similarities than differences in the food and agriculture sectors of these two nations.This essay,adopting some of the themes of the Sino-American Symposium on Future Issues Affecting Quality of Life,presents a limited but representative comparative assessment of three of the most important shared challenges impacting the agricultural sectors of China and the United States for the period from 2000 to the present including 1)environmental challenges related to agricultural water supply,2)declines in farm labor and rural population,and 3)growing food-related concerns and challenges.For both nations,excessive and unsustainable groundwater consumption has lowered water tables and limited crop production.Rural populations and farm workforces in both nations are also declining,leading to labor challenges in both nations.Finally,concerns regarding food safety are also very similar with major challenges to the farm sector associated with consumer resistance to genetically modified food crops and sanitation issues linked to lengthening supply chains.All of these issues threaten the development of sustainable agricultural production systems. 展开更多
关键词 AGRICULTURE Food safety China United states Sino-US comparative study
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Contextual Adaptation of Language Choices -With Reference to Obama's 2015 State of the Union Address 被引量:1
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《International English Education Research》 2015年第4期94-96,共3页
An empirical research is done on how political Obama's 2015 State of the Union Address as the corpora sample speeches adapt to context in the framework of adaptation theory, taking This paper shows that language choi... An empirical research is done on how political Obama's 2015 State of the Union Address as the corpora sample speeches adapt to context in the framework of adaptation theory, taking This paper shows that language choices in the State of the Union Address are adaptive to all the levels of the context, including communicative context (language users, mental world, social world, and physical world) and linguistic context. It is confirmed one of the theoretical stances of adaptation theory that there is no language use without being adaptive to context. 展开更多
关键词 contextual adaptation 2015 state of the Union Address of the USA case study
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An available formula of the sandy beach state induced by plunging waves
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作者 JIANG Changbo WU Zhiyuan +3 位作者 CHEN Jie DENG Bin LONG Yuannan LI Lianjie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第9期91-100,共10页
Laboratory experiments are performed to explore the response rule of a sandy beach profile under plunging wave on a non-uniform sediment-bed slope. The initial beach slope of combination of 1/10 and 1/20 is exposed to... Laboratory experiments are performed to explore the response rule of a sandy beach profile under plunging wave on a non-uniform sediment-bed slope. The initial beach slope of combination of 1/10 and 1/20 is exposed to regular waves and cnoidal waves respectively. The free surface elevation, process of wave propagation, wave breaking, uprush and backwash and the change of a cross-shore beach profile are measured and recorded. The beach profile under the regular waves action exhibits two parts: a sandbar profile and a beach berm profile, and only one typical profile transformation under the cnoidal waves action is obtained, which is the beach berm profile. In the laboratory experiments, it is found that the beach states under wave action related to the previous factors. In addition, they are related to the characteristic of breaking waves such as the breaking intensity of the plunging wave. A concept about the characteristic angle of the plunging wave has been put forward through the observation and analysis of the phenomenon of the laboratory experiment. A qualitative analysis about the sediment transport carrying by currents generated from the plunging wave and the state of beach profile under the wave action has been done. The quantitative analysis about the relationship between the characteristic angle and Irribarren number has been done. An available formula of equilibrium states for the sandy beach induced by the plunging wave has been established based on the relationship between Irribarren number and the beach profile. By fitting these experimental results and others' experimental results to three lines, the three fitting coefficients can be calculated in their formula respectively. The recommended empirical formulas can divide three states of a beach morphology profile obviously, which include a depositive beach, an erosive beach and an intermediate beach. 展开更多
关键词 formula of beach state plunging wave experimental study regular wave cnoidal wave
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STUDIES ON SOLID STATE REACTIONS OF COORDINATION COMPOUNDS(LXⅡ)Solid state synthesis and crystal structure of the complex ICu_(0.84)Au_(0.16)(PPh_3)_2(SC(Ph)NHPh)CIJ·0.5CS_2
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作者 Shi An BAO Jian Ping LANG Xin Quan XIN Coordination Chemistry Institute,Nanjing University,Nanjing 210008Kai Bei YU Chengdu Center of Analysis and Measurement,Academica Sinica,Chengdu 610015 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第12期1027-1028,共2页
[Cu_(0.84)Au_(0.16)(PPh_3)_2(SC(Ph)NHPh)Cl]·0.5CS_2=,Mr=895.79,monoclinic,space group P2_1/a,a=17.231(3),b=14.611(2),c=18.000(3) ,β=105.56(2)°,V=4365(1) ~3, Z=4,D_c=1.37g/cm^3.,λ(MoK_α)=0.71073 ,μ=12.15c... [Cu_(0.84)Au_(0.16)(PPh_3)_2(SC(Ph)NHPh)Cl]·0.5CS_2=,Mr=895.79,monoclinic,space group P2_1/a,a=17.231(3),b=14.611(2),c=18.000(3) ,β=105.56(2)°,V=4365(1) ~3, Z=4,D_c=1.37g/cm^3.,λ(MoK_α)=0.71073 ,μ=12.15cm^(-1),F(000)=1855,R=0.052, R_W=0.045 for 3930 observed reflections with Ⅰ>1.5σ(Ⅰ).The central metal atom has a dis. torted tetrahedral geometry with bond lengths Cu-S=2.384(2) (Au-S=2.389(4)), Cu-Cl=2.481(3)(Au-Cl=2.474(1))and Cu-P=2.269(2)-2.289(2)(Au-P=2.270(4)-2.279(4)) . 展开更多
关键词 STUDIES ON SOLID state REACTIONS of COORDINATION COMPOUNDS CS Ph)NHPh)CIJ AU LX PPh3 Solid state synthesis and crystal structure of the complex ICu SC
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