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CIIS President Meets with UN General Assembly Co-Chairs of Intergovernmental Negotiations on Security Council Reform
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《China International Studies》 2024年第1期F0004-F0004,共1页
On February 28,CIIS President Chen Bo,along with scholars in relevant fields,met with Co-chairs of the Intergovernmental Negotiations on the United Nations Security Council Reform of the 78th session of the UN General... On February 28,CIIS President Chen Bo,along with scholars in relevant fields,met with Co-chairs of the Intergovernmental Negotiations on the United Nations Security Council Reform of the 78th session of the UN General Assembly,Permanent Representative of Kuwait to the UN Tareq M.A.M.Albanai and Permanent Representative of Austria to the UN Alexander Marschik. 展开更多
关键词 governmental NEGOTIATION PRESIDENT
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Locally Enhanced Flow and Electric Fields Through a Tip Effect for Efficient Flow‑Electrode Capacitive Deionization
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作者 Ziquan Wang Xiangfeng Chen +5 位作者 Yuan Zhang Jie Ma Zhiqun Lin Amor Abdelkader Maria‑Magdalena Titirici Libo Deng 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期1-17,共17页
Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer... Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current collectors.Herein,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport significantly.The effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal resistance.With the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current collectors.Meanwhile,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current collectors.Additionally,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability. 展开更多
关键词 Flow-electrode Capacitive deionization Current collector Tip effect DESALINATION
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Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel
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作者 Mei Zhang Wenhao Li +3 位作者 Yangfei Chen Yang Jiang Xiaofei Guo Han Dong 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期369-379,共11页
The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile testing.In-situ observations under scanning electron microscopy,transmiss... The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile testing.In-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation mechanisms.These findings were discussed with the local strain measurements via digital image correlation.The results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of yielding.The small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier effect.The volume fraction of RA gradually decreased from 26.8%to 8.2%prior to fracture.In the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase. 展开更多
关键词 medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation
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Wafer‑Scale Vertical 1D GaN Nanorods/2D MoS_(2)/PEDOT:PSS for Piezophototronic Effect‑Enhanced Self‑Powered Flexible Photodetectors
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作者 Xin Tang Hongsheng Jiang +3 位作者 Zhengliang Lin Xuan Wang Wenliang Wang Guoqiang Li 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期102-116,共15页
van der Waals(vdW)heterostructures constructed by lowdimensional(0D,1D,and 2D)materials are emerging as one of the most appealing systems in next-generation flexible photodetection.Currently,hand-stacked vdW-type phot... van der Waals(vdW)heterostructures constructed by lowdimensional(0D,1D,and 2D)materials are emerging as one of the most appealing systems in next-generation flexible photodetection.Currently,hand-stacked vdW-type photodetectors are not compatible with large-areaarray fabrication and show unimpressive performance in self-powered mode.Herein,vertical 1D GaN nanorods arrays(NRAs)/2D MoS_(2)/PEDOT:PSS in wafer scale have been proposed for self-powered flexible photodetectors arrays firstly.The as-integrated device without external bias under weak UV illumination exhibits a competitive responsivity of 1.47 A W^(−1)and a high detectivity of 1.2×10^(11)Jones,as well as a fast response speed of 54/71μs,thanks to the strong light absorption of GaN NRAs and the efficient photogenerated carrier separation in type-II heterojunction.Notably,the strain-tunable photodetection performances of device have been demonstrated.Impressively,the device at−0.78%strain and zero bias reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W^(−1),a detectivity of 2.6×10^(11)Jones,and response times of 40/45μs,which are superior to the state-of-the-art self-powered flexible photodetectors.This work presents a valuable avenue to prepare tunable vdWs heterostructures for self-powered flexible photodetection,which performs well in flexible sensors. 展开更多
关键词 Vertical nanorod arrays van der Waals heterostructure Piezophototronic effect Self-powered photodetection Flexible sensors
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Enhanced selectivity of catalytic hydrogenation of halogenated nitroaromatics by interfacial effects
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作者 HUANG Rui LIU Shengjie +1 位作者 WU Qingyuan ZHENG Nanfeng 《无机化学学报》 北大核心 2025年第1期201-212,共12页
The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts c... The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts contained Pd species in mixed valence states,with high valence Pd at the metal‑support interface and zero valence Pd at the metal surface.While the strong coordination of triphenylphosphine(PPh3)to Pd0 on the Pd surface prevents the adsorption of halogenated nitroaromatics and thus dehalogenation,the coordination of sodium metavanadate(NaVO3)to high‑valence Pd sites at the interface helps to activate H2 in a heterolytic pathway for the selective hydrogenation of nitro‑groups.The excellent catalytic performance of the interfacial active sites enables the selective hydrogenation of a wide range of halogenated nitroaromatics. 展开更多
关键词 halogenated nitroaromatic heterogeneous catalysis HYDROGENATION selectivity control interfacial effect
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Novel Methodologies for Preventing Crack Propagation in Steel Gas Pipelines Considering the Temperature Effect
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作者 Nurlan Zhangabay Ulzhan Ibraimova +4 位作者 Marco Bonopera Ulanbator Suleimenov Konstantin Avramov Maryna Chernobryvko Aigerim Yessengali 《Structural Durability & Health Monitoring》 EI 2025年第1期1-23,共23页
Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crac... Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crack,strengthened by steel wire wrapping.The effects of the thread tensile force of the steel winding in the form of single rings at the crack edges and the wires with different winding diameters and pitches were also studied.The results showed that the strengthening was preferably executed at a minimum value of the thread tensile force,which was 6.4%more effective than that at its maximum value.The analysis of the influence of the winding dia-meters showed that the equivalent stresses increased by 32%from the beginning of the crack growth until the wire broke.The increment in winding diameter decelerated the disclosure of the edge crack and reduced its length by 8.2%.The analysis of the influence of the winding pitch showed that decreasing the distance between the winding turns also led to a 33.6%reduction in the length of the straight crack and a 7.9%reduction in the maximum stres-ses on the strengthened pipeline cross-section.The analysis of the temperature effect on the pipeline material,within a range from-40℃ to+50℃,resulted in a crack length change of up to 5.8%.As the temperature dropped,the crack length decreased.Within such a temperature range,the maximum stresses were observed along the cen-tral area of the crack,which were equal to 413 MPa at+50℃ and 440 MPa at-40℃.The results also showed that the presence of the steel winding in the pipeline significantly reduced the length of crack propagation up to 8.4 times,depending on the temperature effect and design parameters of prestressing.This work integrated the existing methods for crack localization along steel gas pipelines. 展开更多
关键词 Crack propagation finite-element internal pressure PRESTRESSING steel gas pipeline temperature effect
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Cumulative effects of stress-sensitivity factors on depressive symptoms and suicide risk:A prospective study
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作者 Xue-Mei Qin Meng-Qi Xu +20 位作者 Ya-Qi Qin Fang-Zhou Shao Mo-Han Ma Wen-Wen Ou Guan-Yi Lv Qian-QianZhang Wen-Tao Chen Xiao-Tian Zhao Ao-Qian Deng Jin-Tao Xiong Ling-Si Zeng Yi-Lin Peng Mei Huang Shu-Yin Xu Mei Liao Li Zhang Ling-Jiang Li Yu-Meng Ju Jin Liu Bang-Shan Liu Yan Zhang 《World Journal of Psychiatry》 2025年第2期173-185,共13页
BACKGROUND Sensitivity to stress is essential in the onset,clinical symptoms,course,and prognosis of major depressive disorder(MDD).Meanwhile,it was unclear how variously classified but connected stress-sensitivity va... BACKGROUND Sensitivity to stress is essential in the onset,clinical symptoms,course,and prognosis of major depressive disorder(MDD).Meanwhile,it was unclear how variously classified but connected stress-sensitivity variables affect MDD.We hypothesize that high-level trait-and state-related stress-sensitivity factors may have different cumulative effects on the clinical symptoms and follow-up outcomes of MDD.AIM To investigate how stress-sensitivity factors added up and affected MDD clinical symptoms and follow-up results.METHODS In this prospective study,281 MDD patients were enrolled from a tertiary care setting.High-level stress-sensitivity factors were classified as trait anxiety,state anxiety,perceived stress,and neuroticism,with a total score in the top quartile of the research cohort.The cumulative effects of stress-sensitivity factors on cognitive dysfunction,disability and functional impairment,suicide risk,and depressive and anxiety symptoms were examined using an analysis of variance with linear trend analysis.Correlations were investigated further using multiple regression analysis.RESULTS Regarding high-level stress-sensitivity factors,53.40%of patients had at least one at baseline,and 29.61%had two or more.Four high-level stress-sensitivity components had significant cumulative impacts on MDD symptoms at baseline(all P<0.001).Perceived stress predicted the greatest effect sizes of state-related factors on depressive symptoms(partialη^(2)=0.153;standardizedβ=0.195;P<0.05).The follow-up outcomes were significantly impacted only by the high-level trait-related components,mainly when it came to depressive symptoms and suicide risk,which were predicted by trait anxiety and neuroticism,respectively(partialη^(2)=0.204 and 0.156;standardizedβ=0.247 and 0.392;P<0.05).CONCLUSION To enhance outcomes of MDD and lower the suicide risk,screening for stress-sensitivity factors and considering multifaceted measures,mainly focusing on trait-related ones,should be addressed clinically. 展开更多
关键词 Major depressive disorder Stress sensitivity Depressive symptoms Suicide risk Cumulative effect
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Experimental and numerical simulation of the attenuation effect of blast shock waves in tunnels at different altitudes
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作者 Changjiang Liu Hujun Li +3 位作者 Zhen Wang Yong He Guokai Zhang Mingyang Wang 《Defence Technology(防务技术)》 2025年第1期120-141,共22页
Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion,which can damage personnel and equipment.Accurate prediction of the distribution pattern of explosive loads ... Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion,which can damage personnel and equipment.Accurate prediction of the distribution pattern of explosive loads and shock wave propagation process in semi-enclosed structures at various altitude environment is key research focus in the fields of explosion shock and fluid dynamics.The effect of altitude on the propagation of shock waves in tunnels was investigated by conducting explosion test and numerical simulation.Based on the experimental and numerical simulation results,a prediction model for the attenuation of the peak overpressure of tunnel shock waves at different altitudes was established.The results showed that the peak overpressure decreased at the same measurement points in the tunnel entrance under the high altitude condition.In contrast,an increase in altitude accelerated the propagation speed of the shock wave in the tunnel.The average error between the peak shock wave overpressure obtained using the overpressure prediction formula and the measured test data was less than15%,the average error between the propagation velocity of shock waves predicted values and the test data is less than 10%.The method can effectively predict the overpressure attenuation of blast wave in tunnel at various altitudes. 展开更多
关键词 Shock wave propagation TUNNEL Altitude effect Peak overpressure Shock waves velocity Engineering safety
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Effect of ligamentum teres uteri preservation in laparoscopic high hernia sac ligation in children with indirect inguinal hernia
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作者 Xiao-Qiang Lin Hua-Fang Li +1 位作者 Yan-Zhu Lin Wen-You Chen 《World Journal of Gastrointestinal Surgery》 2025年第1期132-138,共7页
BACKGROUND Routinely separating the ligamentum teres uteri(LTU)intraoperatively remains an unresolved issue for female children undergoing surgery for indirect inguinal hernia(IIH).AIM To identify the effect of LTU pr... BACKGROUND Routinely separating the ligamentum teres uteri(LTU)intraoperatively remains an unresolved issue for female children undergoing surgery for indirect inguinal hernia(IIH).AIM To identify the effect of LTU preservation in laparoscopic high hernia sac ligation(LHSL)in children with IIH.METHODS The participants were 100 female children with unilateral IIH admitted from April 2022 to January 2024 to the Pediatric Surgery Department of Zhangzhou Municipal Hospital of Fujian Province.They were categorized based on LTU retention into the control group(n=45 cases),which underwent LTU ligation intraoperatively,and the experimental group(55 cases),which had the LTU preserved intraoperatively.All children underwent LHSL.RESULTS This study comparatively analyzed the operation time,hospitalization time,blood loss,postoperative recurrence rate,and complications(repeated pain in the inguinal region,foreign body sensation in the inguinal region,bloody exudation at the inguinal incision,and incision infection),which were all comparable between the two groups.CONCLUSION The above results indicate that LTU preservation during LHSL exerts certain therapeutic benefits for children with IIH.LTU preservation does not increase hospitalization time,blood loss,postoperative recurrence rate,and complications,which is safe and feasible,compared with conventional LTU ligation.LHSL with LTU preservation should be performed if conditions permit,which is worth popularizing. 展开更多
关键词 Indirect inguinal hernia Laparoscopic high hernia sac ligation Ligamentum teres uteri Therapeutic effect Pediatric surgery
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The Major Problems and the Governmental Role in Chinese Rural Land Transfer 被引量:8
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作者 ZHANG Cen-cheng 《Asian Agricultural Research》 2011年第7期62-65,共4页
On the basis of clarifying and defining rural land transfer, the necessity of rural land transfer is analyzed. Land transfer is the necessity in terms of promoting agricultural scale operation and improving production... On the basis of clarifying and defining rural land transfer, the necessity of rural land transfer is analyzed. Land transfer is the necessity in terms of promoting agricultural scale operation and improving production efficiency; proving opportunities for narrowing urban and rural gap; realizing rural surplus labor transfer and facilitating urbanization. Major problems in the existing rural land transfer are analyzed:unclear laws and regulations and rural land transfer lacks relevant legal protection;rural social security system is imperfect and can not solve farmers' worries after land transfer; farmers and local governments are restricted by traditional ideas and it is hard to carry out the land transfer policies; rural system construction is relatively backward and the rural land transfer market is immature. Countermeasures on the governmental behaviors in rural land transfer are put forward: stipulating relevant administrative laws and regulations and perfecting the political system of rural land transfer; perfecting rural social security system and solving farmers' worries after land transfer; changing the ideas and working style of local officials and leading farmers to form the scientific land transfer outlook;and vigorously promoting the construction of system and positively cultivating rural land transfer market. 展开更多
关键词 Rural land transfer Major problems governmental behaviors China
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Governmental policies on HIV infection in China 被引量:4
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作者 Jie SHEN Dong Bao YU 《Cell Research》 SCIE CAS CSCD 2005年第11期903-907,共5页
This article is a general review of the evolvement of HIV/AIDS-related public policies in China since 1980’s. It tracks the important laws, regulations and other governmental documents in regard to HIV/AIDS preventio... This article is a general review of the evolvement of HIV/AIDS-related public policies in China since 1980’s. It tracks the important laws, regulations and other governmental documents in regard to HIV/AIDS prevention mainly at central level. 展开更多
关键词 HIV/AIDS government policies
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Government Intervention Measures Effectively Control COVID-19 Epidemic in Wuhan,China 被引量:2
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作者 Xing XIN Shu-fang LI +6 位作者 Ling CHENG Chang-yu LIU Yin-juan XIN Hai-long HUANG Raijluxmee Beejadhursing Shao-shuai WANG Ling FENG 《Current Medical Science》 SCIE CAS 2021年第1期77-83,共7页
The coronavirus disease 2019(COVID-19)outbreak has been brought under control through a nationwide effort,and now it has become a global pandemic and the situation seems grim.We summarized the measures taken in Wuhan ... The coronavirus disease 2019(COVID-19)outbreak has been brought under control through a nationwide effort,and now it has become a global pandemic and the situation seems grim.We summarized the measures taken in Wuhan and analyzed the effects to comprehensively describe the factors involved in controlling the COVID-19 in China.In China,several measures such as the lockdown of Wuhan,restriction of traffic and communities,increasing hospital beds,nationwide support from medical staff,epidemic prevention equipment and supplies,and establishment of makeshift shelter hospitals have been taken.The lockdown of Wuhan reduced the propagation of cases to other cities in Hubei province and throughout China,traffic and community restrictions reduced the flow of population and the spread of disease,increasing wards and beds and medical personnel reduced the incidence of severe cases and mortality,the establishment of the Fangcang shelter hospitals provided a good isolation and monitoring environment,and further reduced the spread and fatality of the disease.The fact that China was able to control the spread of COVID-19 within three months without a specific drug or vaccine suggests that these measures are more adequate and effective. 展开更多
关键词 COVID-19 China's Mainland government intervention measures healthcare
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Net Pension Liability Impact on School Districts after Incorporation of Governmental Accounting Standards Boards (GASB) Statement Number 68 被引量:1
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作者 Michael J.Gallagher Emily F.Gallagher 《Journal of Business Administration Research》 2019年第1期45-53,共9页
This paper analyzes twenty school districts in the state of Pennsylvania and applies ratio analysis to understand the potential effect of GASB number 68 on the financial statements of these entities.The financial stat... This paper analyzes twenty school districts in the state of Pennsylvania and applies ratio analysis to understand the potential effect of GASB number 68 on the financial statements of these entities.The financial statements were picked on a random basis from the Electronic Municipal Market Access[1]database.EMMA is a research and data retrieval system of the Municipal Securities Rulemaking Board(MSRB).The MSRB provides resources to trade municipal bonds and access to the financial statements of entities selling these securities.The paper was developed as a result of the requirement by GASB to“recognize their long-term obligation for pension benefits as a liability for the first time,and to more comprehensively and comparably measure the annual costs of pension benefits”[2].The public schools in Pennsylvania incorporated GASB number 68 for the fiscal year ended June 30,2015 and restated the financial statements for the fiscal year ended June 30,2014.The effects of these restatements created a situation where most of these districts now show a negative fund balance caused by an increase of liabilities of over one hundred percent.Many of the decision makers are uncertain of the long-term changes that this recognition will have on the operations of the school district.Bond ratings have suffered because of the volatility and uncertainty causing negative effects on the balance sheet,increased current recognition of pension expenses,and a possible interest rate increase.All of these effects are illustrated in this paper.This is at a time where many people are questioning the performance of many of the school districts. 展开更多
关键词 Pensions governmental ACCOUNTING government ACCOUNTING Standards Board Concept Statement#68
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Decision-Making in a Governmental Healthcare Organization by Analytic Hierarchy Process 被引量:1
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作者 Fumihiko Isada 《Journal of Modern Accounting and Auditing》 2012年第3期322-329,共8页
This paper contains research on strategic decision-making in a local government. In a profit-oriented organization, the option that maximizes profits tends involve reaching an agreement between stakeholders. However, ... This paper contains research on strategic decision-making in a local government. In a profit-oriented organization, the option that maximizes profits tends involve reaching an agreement between stakeholders. However, there is tendency for stakeholders to differ in their beliefs as to what is desirable particularly in a non-profit organization. In a local government, it is especially difficult for the interests of a stakeholder group to be completely in agreement. This research considers the use of the analytical hierarchy process (Saaty, 1971) as a solution for one of the difficulties of decision-making in a local government. This research is a case study to explore the strategy of a local Japanese healthcare management organization. The conclusion was drawn to decide which strategic option should be taken by using the analytical hierarchy process. Also, it was found what to work on a countermeasure that prevents the negative effects that are generated by selecting the strategic option. 展开更多
关键词 DECISION-MAKING local governmental organization non-profit organization analytic hierarchy process
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Construction of Governmental Function Network Based on the Perspective of Problem of Farmers Who Lose Their Land
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作者 LI Cui-ping,WANG Yu-hua College of Water Conservancy & Civil Engineering,China Agricultural University,Beijing 100083,China 《Asian Agricultural Research》 2011年第3期52-56,共5页
This paper illustrates three developmental stages of the functional transformation of western governments characterized by different extent of state involvement in economic activities.It investigates the functional ro... This paper illustrates three developmental stages of the functional transformation of western governments characterized by different extent of state involvement in economic activities.It investigates the functional role of nation-state in urbanization process in the context of western advanced economies with a particular focus on the laws and regulations,delineating the subjects,objectives,operational procedure,approval system,compensation standard and so on in relation to land expropriation.It also discusses the direction of the adjustment of state functions in China along three lines,including the transformation from political government to economic government,from direct management to indirect management and from comprehensive government to service-oriented and limited government.The paper probes into the roles that Chinese government should play in the urbanization process of land-lost peasants in terms of institutional innovation,optimal utilization of land compensation and related rules and regulations.Finally,it provides policy recommendations for the establishment of three-level state functional networks in order to address the challenge posed by amounting number of land-lost peasants. 展开更多
关键词 Landless FARMERS URBANIZATION governmental functio
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Research of Mechanism on the Impact of Local Governmental Competition on Farmland Conversion
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作者 CHEN Shi-cong LI Jian-qiang 《Asian Agricultural Research》 2011年第1期104-107,111,共5页
In the perspective of local governmental competition, the impact of local governmental competition on farmland conversion is analyzed in terms of political competition, factors competition and products competition, an... In the perspective of local governmental competition, the impact of local governmental competition on farmland conversion is analyzed in terms of political competition, factors competition and products competition, and the empirical analysis is conducted according to the provincial data from 2002 to 2007. The results show that the endowment of land resources correlates negatively with the scale of farmland conversion, and the population, the tendency of exceeding capital investment and the competition of research and development input correlate positively with the scale of farmland conversion. According to these research results, corresponding policies and countermeasures are put forward: we should overhaul the system of performance evaluation of local governmental officials; we should normalize the local governmental competitive behavior. 展开更多
关键词 LOCAL governmental COMPETITION FARMLAND FARMLAND c
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240 nm AlGaN-based deep ultraviolet micro-LEDs:size effect versus edge effect 被引量:2
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作者 Shunpeng Lu Jiangxiao Bai +6 位作者 Hongbo Li Ke Jiang Jianwei Ben Shanli Zhang Zi-Hui Zhang Xiaojuan Sun Dabing Li 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期55-62,共8页
240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge ef... 240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge effects.Here,it is revealed that the peak optical output power increases by 81.83%with the size shrinking from 50.0 to 25.0μm.Thereinto,the LEE increases by 26.21%and the LEE enhancement mainly comes from the sidewall light extraction.Most notably,transversemagnetic(TM)mode light intensifies faster as the size shrinks due to the tilted mesa side-wall and Al reflector design.However,when it turns to 12.5μm sized micro-LEDs,the output power is lower than 25.0μm sized ones.The underlying mechanism is that even though protected by SiO2 passivation,the edge effect which leads to current leakage and Shockley-Read-Hall(SRH)recombination deteriorates rapidly with the size further shrinking.Moreover,the ratio of the p-contact area to mesa area is much lower,which deteriorates the p-type current spreading at the mesa edge.These findings show a role of thumb for the design of high efficiency micro-LEDs with wavelength below 250 nm,which will pave the way for wide applications of deep ultraviolet(DUV)micro-LEDs. 展开更多
关键词 ALGAN deep ultraviolet micro-LEDs light extraction efficiency size effect edge effect
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Study on Issues Concerning Regional Intergovernmental Cooperative Governance in Guangxi Beibu Gulf Economic Zone
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作者 WANG De-rong,YAN Zhi-qiang Guangxi Normal University,Nanning 530007, China 《Asian Agricultural Research》 2011年第12期7-11,共5页
Guangxi Beibu Gulf Economic Zone has taken the initiative to explore how to promote public administration of interregional local governments and achieved some success in recent years. However, there are still many pro... Guangxi Beibu Gulf Economic Zone has taken the initiative to explore how to promote public administration of interregional local governments and achieved some success in recent years. However, there are still many problems as follows: the cooperation never goes deep;the cooperative governance is devoid of necessary system guarantee and information exchange and share platform. We analyse the status quo of cooperation in regional intergovernmental public administration as follows: it integrates the hierarchy power of government; it sponsors the forum for strengthening public administration and deepening cooperation in Beibu Gulf Economic Zone; it accelerates regional transportation system building; it sets up public administration institution; it quickens the pace of innovation of management and system in Beibu Gulf Economic Zone. Finally we put forward the path to construction of regional government cooperative governance so as to promote sustainable regional development as follows: construct the composite regional administrative cooperative governance model; construct the regional administrative network organization governance model; construct regional administrative special-project-based intergovernmental cooperative governance model; construct long-term flexible regional administrative cooperative mechanism. 展开更多
关键词 REGIONAL government government GOVERNANCE GUANGXI
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Engineering Strategies for Suppressing the Shuttle Effect in Lithium–Sulfur Batteries 被引量:3
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作者 Jiayi Li Li Gao +7 位作者 Fengying Pan Cheng Gong Limeng Sun Hong Gao Jinqiang Zhang Yufei Zhao Guoxiu Wang Hao Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期187-221,共35页
Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-elect... Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-electron reaction between sulfur and lithium in liquid electrolyte makes the capacity much smaller than the theoretical value.Many methods were proposed for inhibiting the shuttle effect of polysulfide,improving corresponding redox kinetics and enhancing the integral performance of Li–S batteries.Here,we will comprehensively and systematically summarize the strategies for inhibiting the shuttle effect from all components of Li–S batteries.First,the electrochemical principles/mechanism and origin of the shuttle effect are described in detail.Moreover,the efficient strategies,including boosting the sulfur conversion rate of sulfur,confining sulfur or lithium polysulfides(LPS)within cathode host,confining LPS in the shield layer,and preventing LPS from contacting the anode,will be discussed to suppress the shuttle effect.Then,recent advances in inhibition of shuttle effect in cathode,electrolyte,separator,and anode with the aforementioned strategies have been summarized to direct the further design of efficient materials for Li–S batteries.Finally,we present prospects for inhibition of the LPS shuttle and potential development directions in Li–S batteries. 展开更多
关键词 Shuttle effect Designed strategies Li-S battery Lithium polysulfides
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Chinese Anti-Cancer Association as a non-governmental organization undertakes systematic cancer prevention work in China 被引量:3
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作者 Tingting Xu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第4期423-427,共5页
Cancer has become the first leading cause of death in the world, particularly in low- and middle-income countries. Facing the increasing trend of cancer incidence and mortality, China issued and implemented "three-ea... Cancer has become the first leading cause of death in the world, particularly in low- and middle-income countries. Facing the increasing trend of cancer incidence and mortality, China issued and implemented "three-early(early prevention, early diagnosis and early treatment)" national cancer prevention plan. As the main body and dependence of social governance, non-governmental organizations(NGOs) take over the role of government in the field of cancer prevention and treatment. American Cancer Society(ACS) made a research on cancer NGOs and civil society in cancer control and found that cancer NGOs in developing countries mobilize civil society to work together and advocate governments in their countries to develop policies to address the growing cancer burden. Union for International Cancer Control(UICC), Cancer Council Australia(CCA), and Malaysian cancer NGOs are the representatives of cancer NGOs in promoting cancer control. Selecting Chinese Anti-Cancer Association(CACA) as an example in China, this article is to investigate how NGOs undertake systematic cancer prevention work in China. By conducting real case study, we found that, as a NGO, CACA plays a significant role in intensifying the leading role of government in cancer control, optimizing cancer outcomes, decreasing cancer incidence and mortality rates and improving public health. 展开更多
关键词 Non-governmental organization(NGO) cancer prevention Chinese Anti-Cancer Association(CACA)
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