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Molecular diffusion in ternary poly(vinyl alcohol)solutions

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Frontiers of Chemical Science and Engineering 2022年第6期16卷 1003-1016页

作者： Katarzyna Majerczak Ophelie Squillace Zhiwei shi Zhanping Zhang Zhenyu J.Zhang School of Chemical Engineering University of BirminghamBirmingham B152TTUK The Procter and Gamble Company CincinnatiOH 45040USA

The diffusion kinetics of a molecular probe-rhodamine B-in ternary aqueous solutions containing poly(vinyl alcohol),glycerol,and surfactants was investigated using fluorescence correlation spectroscopy and dynamic light *** show that the diffusion characteristics of rhodamine B in such complex systems is determined by a synergistic effect of molecular crowding and intermolecular interactions between chemical *** presence of glycerol has no noticeable impact on rhodamine B diffusion at low concentration,but significantly slows down the diffiision of rhodamine B above 3.9%(w/v)due to a dominating steric inhibition ***,introducing surfactants(cationic/nonionic/anionic)to the system results in a decreased diffusion coefficient of the molecular *** solutions containing nonionic surfactant,this can be explained by an increased crowding *** ternary poly(vinyl alcohol)solutions containing cationic or anionic surfactant,surfactant-polymer and surfactant-rhodamine B interactions alongside the crowding effect of the molecules slow down the overall diffiisivity of rhodamine *** results advance our insight of molecular migration in a broad range of industrial complex formulations that incorporate multiple compounds,and highlight the importance of selecting the appropriate additives and surfactants in formulated products.

关键词： fluorescence correlation spectroscopy poly(vinyl alcohol) anomalous diffusion crowding effects dynamic light scattering binding effects rhodamine B

Brightening thiocyanate-anion layered perovskite through internal stress modulated nano phase segregation

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Nano Research 2023年第4期16卷 5533-5540页

作者： Yiming Li Jiangjian shi Huijue Wu Yanhong Luo Dongmei Li Qingbo Meng Key Laboratory for Renewable Energy Chinese Academy of SciencesBeijing Key Laboratory for New Energy Materials and DevicesInstitute of PhysicsChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Huairou Division Institute of PhysicsChinese Academy of SciencesBeijing 101400China Songshan Lake Materials Laboratory Dongguan 523808China

Thiocyanate-anion(SCN−)two-dimensional(2D)layered perovskite with internal stress-controlled nano phase segregation has been firstly demonstrated as a promising material system for luminescence *** interesting energy band structure is found as well as charge transfer process caused by nano phase segregation,which provide an alternative route to overcome the indirect-bandgap luminescence limit of SCN layered *** is revealed that,within the SCN layered framework,the segregated nano phases exist in a quantum well form,possessing much higher carrier localization and second-order radiative recombination *** the help of internal stress modulation,these advantages can be significantly enhanced and finally contribute to high luminescence performances in visible-red *** work provides more potential opportunities for 2D layered perovskite materials in the future optoelectronic applications.

关键词： two-dimensional perovskite internal stress thiocyanate anion phase segregation luminescence

Simulation of the Power Take-off System for a Heaving Buoy Wave Energy Converter

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Journal of Ocean University of China 2020年第3期19卷 497-504页

作者： CAO Feifei shi Hongda LI Ming DONG Xiaochen LI Demin College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Qingdao 266100China Qingdao Municipal Key Laboratory of Ocean Renewable Energy Qingdao 266100China

The heaving buoy wave energy device is popular for wave conditions with small wave heights and short periods. This paper presents the design of a wave energy converter composed of a gyro buoy, a hydraulic power take-off, and an electricity generation system. The energy accumulators are used to improve the output power with different control strategies. The quantity relations between each component are established using theoretical methods. The simulation model describes the energy conversion and calculates the operation time, energy capacity, and output power of the device under different initial pressures, release pressures, and electric resistances. As a result, the capacity is determined by the electronic load, and the maximum output power can be obtained when the accumulators are turned on and off at the same time. This study investigates the factors influencing the electric energy production and can be used to guide the optimization of this type of device.

关键词： wave energy heaving buoy power-take-off accumulator output power

Efficient scale of prefectural government in China

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China Finance and Economic Review 2016年第1期5卷 88-109页

作者： Mototsugu Fukushige shi Yingxin Graduate School of Economics Osaka University Department of Economics and Management Dalian Nationalities UniversityChina

China has five layers of government including the central ***,some prefectural governments meet fiscal *** investigate the effects of urban and rural populations and area sizes on the expenditures of the prefecture-level local government by estimating quintile *** around 220,000 people,per capita local government expenditure for urban populations is minimized in our *** expenditure for rural populations is proportional to the population *** expenditure in accordance with the areas is also proportional to the area *** cost structure is the reason why China’s recent rapid urbanization increases prefectural government’s fiscal distress.

关键词： efficient scale local government quantile regression China

Cross-national Perspectives on Using Sustainable Development Goals(SDGs) Indicators for Monitoring Sustainable Development: A Database and Analysis

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Chinese Geographical Science 2021年第4期31卷 600-610页

作者： WANG Xiangyu SONG Changqing CHENG Changxiu YE Sijing SHEN shi Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China Center for Geodata and Analysis Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China National Tibetan Plateau Data Center Beijing 100101China

Sustainable development is the theme of the 21st century. To monitor the progress of sustainable development, the United Nations launched Sustainable Development Goals(SDGs) in 2015. Subsequently, nations of the world have drawn up a list of localized indicators regarding the United Nations SDGs as a paradigm. We established a database including SDGs indicator systems of 11 economies by collecting and determining a large number of materials. Based on this database, we analyzed SDGs indicators by designing a conceptual framework of comparative analysis that included three views. We found that the SDGs indicator systems of 11 economies are different between the number of indicators, the proportion of different categories, and the connotation of indicators. Although the SDGs indicator systems among economies regarded the United Nations SDGs as a framework and included the major social problems related to sustainability, the inconsistency between SDGs indicator systems is large. It is a major reason why scholars lack the systematic method for developing indicators. There are challenges faced in data accessibility. The framework for comparative analysis could be applied to different economies.

关键词： Sustainable Development Goals(SDGs) framework indicator cross-national database

Petrogenesis of the~1.94 Ga Meta-gabbronorites in Liangcheng:Implications for Tectonic Evolution of the Khondalite Belt,North China Craton

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Acta Geologica Sinica(English Edition) 2023年第2期97卷 418-435页

作者： LIAN Guanghui REN Yunwei shi Jianrong XU Zhongyuan FENG Fan College of Earth Sciences Jilin UniversityChangchun 130061China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural ResourcesChangchun 130061China Tianjin Center China Geological SurveyTianjin 300170China Precambrian Geological Research Centre China Geological SurveyTianjin 300170China

We investigated the meta-gabbronorites in Liangcheng and used detailed petrography,geochemistry,zircon geochronological and in-situ Hf isotopic studies to clarify their formation and metamorphic ages,petrogenesis,tectonic setting and provide constraints on the tectonic evolution of Khondalite Belt(KB).The zircon U-Pb dating results show that the meta-gabbronorites crystallized at~1.94 Ga and were metamorphosed at~1.91–1.89 *** can be subdivided into the low-Mg and high-Mg *** low-Mg meta-gabbronorites contain relatively lower MgO and higher SiO2 contents than high-Mg *** are enriched in light rare earth elements and large ion lithophile elements,depleted in high field strength elements,and exhibit positive(high-Mg meta-gabbronorites)and negative(low-Mg metagabbronorites)Sr and Eu *** zircon in-situεHf(t)of meta-gabbronorites is 0.07–4.12,with Hf model ages(TDM)of 2169–2400 *** meta-gabbronorites in Liangcheng originated from the asthenospheric mantle and experienced fractional crystallization of olivine,orthopyroxene,clinopyroxene,and *** were contaminated by the crustal rocks(mainly khondalite series)during ascent,especially for low-Mg *** ridge subduction is the most plausible tectonic setting for meta-gabbronorites,indicating the eastern segment of KB was in a ridge subduction setting at~1.94 Ga following an orogenic thickening event during a prolonged orogenic process.

关键词： meta-gabbronorites Paleoproterozoic Liangcheng Khondalite Belt North China Craton

Origin of the Dashuigou independent tellurium deposit at Qinghai–Xizang Plateau: constraints from the light stable isotopes C, O, and H

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Acta Geochimica 2024年第2期43卷 385-398页

作者： Jianzhao Yin Yuhong Chao Haoyu Yin Hongyun shi Shoupu Xiang Wuhan Institute of Technology Wuhan 430074China College of Earth Sciences Jilin UniversityChangchun 130061China Ganzhongnan Institute of Geology and Mineral Exploration Nanchang 330002China Guinea Westfi eld Mining Company-Sarlu Jinzhong 031300China Orient Resources Ltd. RichmondB.C.V7E 1M8Canada Silvercorp Metals Inc. Beijing 100027China

By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic *** δ^(18)O and δ^(13)C isotope signatures of dolomite samples vary between 10.2 and 13.0‰,and between−7.2 and−5.2‰,respectively,implying that the carbon derives from the upper mantle.δD and δ^(18) O of quartz,biotite,and muscovite from diff erent ore veins of the deposit vary between−82 and−59‰,and between 11.6 and 12.4‰,respectively,implying that the metallogenic solutions are mainly *** to the relevant research results of many isotope geologists,the fractionation degree of hydrogen isotopes increases as the depth to the Earth’s core increases,and the more diff erentiated the hydrogen isotopes are,the lower their values will *** other words,mantle-derived solutions can have extremely low hydrogen isotope *** means that the δD‰ value−134 of the pyrrhotite sample numbered SD-34 in this article may indicate mantle-derived oreforming fl uid of the *** formation of the Dashuigou tellurium deposit occurred between 91.71 and 80.19 Ma.

关键词： Carbon oxygen and hydrogen isotopes Origin Independent tellurium deposit The Qinghai–Xizang Plateau

Cellular metabolism and homeostasis in pluripotency regulation

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Protein & Cell 2020年第9期11卷 630-640页

作者： Kun Liu Jiani Cao Xingxing shi Liang Wang Tongbiao Zhao State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Pluripotent stem cells(PSCs)can immortally self-renew in culture with a high proliferation rate,and they possess unique metabolic characteristics that facilitate pluripotency ***,we review recent progress in understanding the mechanisms that link cellular metabolism and homeostasis to pluripotency regulation,with particular emphasis on pathways involving amino acid metabolism,lipid metabolism,the ubiquitin-proteasome system and *** of amino acids and lipids is tightly coupled to epigenetic modification,organelle remodeling and cell signaling pathways for pluripotency *** harness enhanced proteasome and autophagy activity to meet the material and energy requirements for cellular *** regulatory events reflect a fine balance between the intrinsic cellular requirements and the extrinsic environment.A more complete understanding of this balance will pave new ways to manipulate PSC fate.

关键词： autophagy amino acid metabolism lipid metabolism pluripotent stem cell(PSC) ubiquitinproteasome system(UPS)

Recent developments in chiral and spin polarization effects in heavy-ion collisions

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Nuclear Science and Techniques 2020年第9期31卷 53-74页

作者： Jian-Hua Gao Guo-Liang Ma shi Pu Qun Wang Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai 264209China Key Laboratory of Nuclear Physics and Ion-Beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China

We give a brief overview of recent theoretical and experimental results on the chiral magnetic effect and spin polarization effect in heavy-ion *** present updated experimental results for the chiral magnetic effect and related *** time evolution of the magnetic fields in different models is *** newly developed quantum kinetic theory for massive fermions is *** present theoretical and experimental results for the polarization of K hyperons and the q00 value of vector mesons.

关键词： Relativistic heavy-ion collisions Chiral magnetic effect Chiral kinetic theory Spin polarization