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Impact of geopolitical risk,GDP,inflation,interest rate,and trade openness on foreign direct investment:Evidence from five Southeast Asian countries
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作者 Md.Shaddam HOSSAIN Liton Chandra VOUMIK +2 位作者 Tahsin Tabassum AHMED Mehnaz Binta ALAM Zabin TASMIM 《Regional Sustainability》 2024年第4期44-56,共13页
Historically,geopolitical risk(GPR)has posed significant challenges to international economic,social,and political frameworks.This study investigated how internal GPR in the selected five Southeast Asian countries(Ind... Historically,geopolitical risk(GPR)has posed significant challenges to international economic,social,and political frameworks.This study investigated how internal GPR in the selected five Southeast Asian countries(Indonesia,South Korea,Malaysia,the Philippines,and Thailand)influences foreign direct investment(FDI)during 1996-2019.The stationarity of the data was assessed using the Augmented Dickey-Fuller(ADF)unit root test,which shows that the data became stationary after the first difference.The Kao,Pedroni,and Westerlund cointegration tests were employed to examine long-term cointegration among the selected variables(FDI,GPR index(GPRI),gross domestic product(GDP),inflation,interest rate,and trade openness(TOP)).The results indicated that these variables have a long-term cointegration.Consequently,regression analysis using the Pooled Ordinary Least Squares(OLS)regression,fixed effect,random effect,Arellano-Bond dynamic panel-data estimation,and system generalized moment method(GMM)revealed that GPRI and TOP negatively impacted FDI in the selected five Southeast Asian countries.At the same time,GDP,inflation,and interest rate positively influenced FDI in these countries.Because FDI is crucial to shaping a country’s macroeconomic structure,this study recommends that governments and central banks of the selected five Southeast Asian countries should implement policies and strategies to encourage foreign investments. 展开更多
关键词 Foreign direct investment Geopolitical risk Gross domestic product(GDP) INFLATION Interest rate Trade openness Southeast Asian countries
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The Customer Requirements Analysis Method of Engineering Products Based on Multiple Preference Information
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作者 Guo Mao 《Proceedings of Business and Economic Studies》 2024年第1期204-209,共6页
To effectively evaluate the fuzziness of the market environment in product planning,a customer requirements analysis method based on multiple preference information is proposed.Firstly,decision-makers use a preferred ... To effectively evaluate the fuzziness of the market environment in product planning,a customer requirements analysis method based on multiple preference information is proposed.Firstly,decision-makers use a preferred information form to evaluate the importance of each customer requirement.Secondly,a transfer function is employed to unify various forms of preference information into a fuzzy complementary judgment matrix.The ranking vector is then calculated using row and normalization methods,and the initial importance of customer requirements is obtained by aggregating the weights of decision members.Finally,the correction coefficients of initial importance and each demand are synthesized,and the importance of customer requirements is determined through normalization.The development example of the PE jaw crusher demonstrates the effectiveness and feasibility of the proposed method. 展开更多
关键词 product planning Customer requirements Importance ratings Multi-format information
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The Influence of the Corrosion Product Layer Generated on the High Strength Low-Alloy Steels Welded by Underwater Wet Welding with Stainless Steel Electrodes in Seawater 被引量:3
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作者 BAI Qiang ZOU Yan +3 位作者 KONG Xiangfeng GAO Yang DONG Sheng ZHANG Wei 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第1期49-56,共8页
The high strength low-alloy steels are welded by underwater wet welding with stainless steel electrodes. The microstructural and electrochemical corrosion study of base metal(BM), weld zone(WZ) and heat affected zone(... The high strength low-alloy steels are welded by underwater wet welding with stainless steel electrodes. The microstructural and electrochemical corrosion study of base metal(BM), weld zone(WZ) and heat affected zone(HAZ) are carried out to understand the influence of the corrosion product layer generated on the high strength low-alloy steels welded by underwater wet welding with stainless steel electrodes, methods used including, potentiodynamic polarization, electrochemical impedance spectroscopy(EIS) and scanning electron microscope(SEM). The results indicate that the WZ acts as a cathode and there is no corrosion product on it throughout the immersion period in seawater. The HAZ and BM acts as anodes. The corrosion rates of the HAZ and BM change with the immersion time increasing. In the initial immersion period, the HAZ has the highest corrosion rate because it has a coarse tempered martensite structure and the BM exhibites a microstructure with very fine grains of ferrite and pearlite. After a period of immersion, the BM has the highest corrosion rate. The reason is that the corrosion product layer on the HAZ is dense and has a better protective property while that on the BM is loose and can not inhibit the diffusion of oxygen. 展开更多
关键词 UNDERWATER WET welding CORROSION rate CORROSION product protective property
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Theoretical prediction of energy dependence for D+BrO→DBr+O reaction:The rate constant and product rotational polarization 被引量:1
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作者 张莹莹 解廷献 +2 位作者 李泽瑞 石英 金明星 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期412-417,共6页
A quasi-classical trajectory(QCT) calculation is used to investigate the vector and scalar properties of the D + Br O → DBr + O reaction based on an ab initio potential energy surface(X1A state) with collision ... A quasi-classical trajectory(QCT) calculation is used to investigate the vector and scalar properties of the D + Br O → DBr + O reaction based on an ab initio potential energy surface(X1A state) with collision energy ranging from 0.1 kcal/mol to 6 kcal/mol. The reaction probability, the cross section, and the rate constant are studied. The probability and the cross section show decreasing behaviors as the collision energy increases. The distribution of the rate constant indicates that the reaction favorably occurs in a relatively low-temperature region(T 〈 100 K). Meanwhile, three product angular distributions P(θr), P(φr), and P(θr, φr) are presented, which reflect the positive effect on the rotational angular momentum j' polarization of the DBr product molecule. In addition, two of the polarization-dependent generalized differential cross sections(PDDCSs), PDDCS00 and PDDCS20, are computed as well. Our results demonstrate that both vector and scalar properties have strong energy dependence. 展开更多
关键词 quasi-classical trajectory cross section rate constant product angular distributions
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ENTROPY PRODUCTION RATE OF THE MINIMAL DIFFUSION PROCESS 被引量:1
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作者 章复熹 钱敏 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期145-152,共8页
The entropy production rate of stationary minimal diffusion processes with smooth coefficients is calculated. As a byproduct, the continuity of paths of the minimal diffusion processes is discussed, and that the point... The entropy production rate of stationary minimal diffusion processes with smooth coefficients is calculated. As a byproduct, the continuity of paths of the minimal diffusion processes is discussed, and that the point at infinity is absorbing is proved. 展开更多
关键词 Minimal diffusion process entropy production rate continuous path
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Heat Production Rate Calculation of Thermal Manikin with a Compensation Method
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作者 朱利军 张渭源 +1 位作者 陈文飞 陈景山 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期79-81,共3页
Thermal manikin plays important roles in simulating thethermal state of human bodies to facilitate the evaluationof thermal comfort properties of various clothing assem-blies.Based on the heat balance principle and an... Thermal manikin plays important roles in simulating thethermal state of human bodies to facilitate the evaluationof thermal comfort properties of various clothing assem-blies.Based on the heat balance principle and analysis ofrelated factors,the heat production rate of manikin isrecommended as an efficient evaluation index.Whereas,its inside heat production which occurs as a result of theexistence of temperature difference between its insidepart and outside surface,should not be ignored.Through a series of theoretical analysis and calculations,a compensative equation is deduced in this paper. 展开更多
关键词 thermal MANIKIN HEAT balance non - evapora-tive HEAT loss HEAT productION rate INNER HEAT productION rate CALCULATION compensation.
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Spatial-temporal Evolvement Characteristics of Climate Productivity for the Plants on Inner Mongolia Desert Steppe 被引量:5
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作者 韩芳 苗百岭 +3 位作者 郭瑞清 李兴华 那日苏 王海 《Meteorological and Environmental Research》 CAS 2010年第5期76-79,共4页
Thornthwaite Memorial model and other statistic methods were used to calculate the climate-productivity of plants with the meteorological data from 1961 to 2007 at 9 stations distributed on Inner Mongolia desert stepp... Thornthwaite Memorial model and other statistic methods were used to calculate the climate-productivity of plants with the meteorological data from 1961 to 2007 at 9 stations distributed on Inner Mongolia desert steppe.The spatial and temporal variation characteristics of climate-productivity were analyzed by using the methods of the tendency rate of the climate trend,accumulative anomaly,and spatial difference and so on.The results showed that the climate-productivity kept linear increased trend over Inner Mongolia desert steppe in recent 47 years,but not significant.In spatial distribution,the climate-productivity reduced with the increased latitude.The climate-productivity in southwest part of Inner Mongolia desert steppe was growing while that in the southeast was reducing.The variation rate of the climate-productivity increased from the northwest part to the southeast part of Inner Mongolia desert steppe.In recent 47 years,the climate-productivity in southeast Jurh underwent the greatest decreasing extent,and the region was the sensitive area of the climate-productivity variation. 展开更多
关键词 Desert steppe Climate productivity Spatial-temporal distribution Variation rate China
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Influence of depressurization rate on gas production capacity of high-rank coal in the south of Qinshui Basin, China
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作者 SU Xuefeng LIU Yan +3 位作者 CUI Zhouqi ZHANG Jianguo YU Li WANG Kai 《Petroleum Exploration and Development》 2019年第3期642-650,共9页
A desorption simulation experiment with the condition of simulated strata was designed. The experiment, under different depressurizing rates and the same fluid saturation, was conducted on the sample from 3# coal of D... A desorption simulation experiment with the condition of simulated strata was designed. The experiment, under different depressurizing rates and the same fluid saturation, was conducted on the sample from 3# coal of Daning coal mine in Jincheng, Shanxi Province. The gas production rate and pressure change at both ends of the sample were studied systematically, and the mechanisms of some phenomena in the experiment were discussed. The experimental results show that, whether at fast or slow depressurizing rate, the methane adsorbed to high-rank coal can effectively desorb and the desorption efficiency can reach above 90%. There is an obvious inflection point on the gas yield curve during the desorption process and it appears after the pressure on the lump of coal reduces below the desorption pressure. The desorption of methane from high-rank coal is mainly driven by differential pressure, and high pressure difference is conducive to fast desorption. In the scenario of fast depressurization, the desorption inflection appears earlier and the gas production rate in the stage of rapid desorption is higher. It is experimentally concluded that the originally recognized strategy of long-term slow CBM production is doubtful and the economic benefit of CBM exploitation from high-rank coal can be effectively improved by rapid drainage and pressure reduction. The field experiment results in pilot blocks of Fanzhuang and Zhengzhuang show that by increasing the drainage depressurization rate, the peak production of gas well would increase greatly, the time of gas well to reach the economic production shortened, the average time for a gas well to reach expected production reduced by half, and the peak gas production is higher. 展开更多
关键词 Qinshui Basin Fanzhuang BLOCK Zhengzhuang BLOCK high-rank COAL DEPRESSURIZATION rate gas production rate simulation experiment gas production capacity
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Soil Carbon Balance in a Native Temperate Grassland in the Xilin River Basin of Inner Mongolia 被引量:3
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作者 李凌浩 韩兴国 +8 位作者 王其兵 白文明 白永飞 闫志丹 陈全胜 张焱 杨晶 李鑫 宋世环 《Acta Botanica Sinica》 CSCD 2002年第6期740-742,共3页
Based on historical data and field investigation, some major fluxes and reserves of carbon were estimated, and a tentative analysis of the soil carbon balance was made in a native grassland community in the Xilin Rive... Based on historical data and field investigation, some major fluxes and reserves of carbon were estimated, and a tentative analysis of the soil carbon balance was made in a native grassland community in the Xilin River basin of Inner Mongolia. Major results were reported as follows: 1) Annual average carbon input from above-ground biomass production was 79.8 g C(.)m(-2.)a(-1), and from root biomass to 30 cm. depth averaged 311.9 g C(.)m(-2.)a(-1). The summed mean annual carbon input of shoot and root materials in the study site was approximately 391.7 g C(.)m(-2.)a(-1). 2) The annual amount of above-ground biomass consumed by insects averaged 14.7 g C(.)m(-2.)a(-1), and the carbon output by leaching or light-chemical oxidation was 3.2 g C(.)m(-2.)a(-1) The annual evolution rate of CO2 from net soil respiration averaged 346.9 g C(.)m(-2.)a(-1), and the summed mean annual output was approximately 364.8 g C(.)m(-2.)a(-1). 3) A mature, steady-state system could be assumed for the community for which growth and decay were approximately in balance, with a net carbon accumulation of about 26.9 g C(.)m(-2.)a(-1). Based on the soil organic carbon density of the field, the turnover Irate of soil carbon in 0 - 30 cm depth was calculated to be 6.2%, with a turnover time of 16 years. 展开更多
关键词 Leymus chinensis steppe carbon balance soil respiration turnover rate net primary productivity (NPP)
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Carbon biomass,production rates and export flux of copepods fecal pellets in the Changjiang(Yangtze) River estuary
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作者 GUO Shujin SUN Xiaoxia 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第4期1244-1254,共11页
Copepod fecal pellets are ubiquitous throughout the oceans. Their production and export can represent a highly efficient pathway of carbon export. However, the role these fecal pellets play in carbon export in the Cha... Copepod fecal pellets are ubiquitous throughout the oceans. Their production and export can represent a highly efficient pathway of carbon export. However, the role these fecal pellets play in carbon export in the Changjiang(Yangtze) River estuary is not well known. Two cruises were carried out in the Changjiang estuary in the spring and summer of 2013, during which time carbon biomass, production, and export of copepod fecal pellets were studied. Spring and summer fecal pellet carbon biomass ranged 0.30–1.01 mg C/m^3(mean=0.56±0.20 mg C/m^3) and 0.31–1.18 mg C/m^3(mean=0.64±0.24 mg C/m^3), respectively, significantly lower than phytoplankton. At most stations, fecal pellet carbon biomass was higher in surface or subsurface layers than deeper layers. Production rates ranged 0.65–1.49 pellets/(ind.?h)(mean=1.02±0.27 pellets/(ind.?h)) in spring and 0.62–1.34 pellets/(ind.?h)(mean=0.98±0.22 pellets/(ind.?h)) in summer, within the range reported in previous studies. Higher production rates of fecal pellets occurred at stations with higher chlorophyll a concentrations, and production rates of copepods of size 500–1 000 μm greater than copepods >1 000 μm during both cruises. The potential export flux of fecal pellets was slightly higher in summer(mean=68.95±14.37 mg C/(m^2 ?d)) than spring(mean=52.08±11.33 mg C/(m^2 ?d)) owing to higher summer copepod abundances. To our knowledge, this study is the first of its kind in the Changjiang estuary, and it confirms the significant role of copepod fecal pellets in local carbon export. 展开更多
关键词 fecal pellets copepods production rates carbon export Changjiang (Yangtze) River estuary
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THE BROAD-BAND CCD PHOTOMETRY AND DUST PRODUCTION RATES OF COMET HALE-BOPP
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作者 Huang Keliang 1 Hu Jingyao 2 Zhou Hongnan 1 (1. Department of Physics, Nanjing Normal University, Nanjing 210097) (2. Beijing Observatory, Chinese Academy of Sciences, Beijing 100080) 《中国科学院上海天文台年刊》 2000年第S1期44-50,共7页
Based upon broad-band CCD observation data of comet Hale-Bopp obtained by a 60cm telescope at Xinglong Station of Beijing Astronomical Observatory during March-August, 1996, the photometric results of comet Hale-Bopp ... Based upon broad-band CCD observation data of comet Hale-Bopp obtained by a 60cm telescope at Xinglong Station of Beijing Astronomical Observatory during March-August, 1996, the photometric results of comet Hale-Bopp are reported. Using the photometric results, the dust production rate, radius and mass of nucleus of comet Hale-Bopp are estimated as follows: dM/dt~1.5×10 5 kgs -1, R n~35.5km, and M n~5.65×10 16kg. 展开更多
关键词 COMET HALE-BOPP - CCD PHOTOMETRY - DUST production rate
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Application of Six Sigma DMAIC Method in Improving the Good Rate of Blank Value of Cytological Method for Dairy Products
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作者 Yunxia WANG Shuhuan ZHAO +3 位作者 Lijun LIU Xue HU Cuizhi LI Zhiyong LU 《Asian Agricultural Research》 2021年第10期48-53,共6页
In this paper,the six Aigma DMAIC method was used to systematically analyze and study the process affecting the good rate of blank value of cytological method for dairy products.Through data collection,analysis and ve... In this paper,the six Aigma DMAIC method was used to systematically analyze and study the process affecting the good rate of blank value of cytological method for dairy products.Through data collection,analysis and verification in each link,the room for improvement in the experimental process was identified.C&E matrix and FMEA were used to analyze the factors affecting the good rate of blank value.Through the DOE experiment design method and risk analysis,the main influencing factors were optimized and improved.The optimized experimental conditions were:silica gel activation temperature(500±50)℃,activation time(23±1)h,cells adherent rate(95±1)%,and single-use of 1.5 mL conical flask.Under the above conditions,the good rate of blank value of cytological method was improved from 52.8%to 100%.The improvement of these conditions is of great significance to ensure the accuracy of results,save the testing cost and improve the testing efficiency. 展开更多
关键词 Six Sigma DMAIC Dairy product Good rate
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A Time Dependent Inventory Model for Exponential Demand Rate with Constant Production Where Shelf-Life of the Product Is Finite
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作者 Mohammad Ekramol Islam Shirajul Islam Ukil Md. Sharif Uddin 《Open Journal of Applied Sciences》 2016年第1期38-48,共11页
In this paper a time dependent inventory model is developed on the basis of constant production rate and market demands which are exponentially decreasing. It advances in quest of total average optimum cost considerin... In this paper a time dependent inventory model is developed on the basis of constant production rate and market demands which are exponentially decreasing. It advances in quest of total average optimum cost considering those products which have finite shelf-life. The model also considers the small amount of decay. Without having any sort of backlogs, production starts. Reaching at the desired level of inventories, it stops production. After that due to demands along with the deterioration of the items it initiates its depletion and after certain periods the inventory gets zero. The decay of the products is level dependent. The objective of this paper is to find out the optimum inventory cost and optimum time cycle. The model has also been justified with proving the convex property and by giving a numerical example. 展开更多
关键词 production Inventory Shelf-Life Time Dependent Demand Class production rate
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Impact of Operating Conditions on the Productivity of Star-Rated Hotels in China's Mainland: Verification from Spatial Metrology
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作者 XIE Ailiang LI Xiubiao +2 位作者 LIU Zhongxiu LIU Chuanyu YU Feng 《Journal of Landscape Research》 2019年第1期87-89,94,共4页
Room occupancy rate is a key indicator of star-rated hotel management quality. This paper takes Cobb-Douglas production function as the theoretical framework. Spatial Moran index of autocorrelation, Spatial Lag Model(... Room occupancy rate is a key indicator of star-rated hotel management quality. This paper takes Cobb-Douglas production function as the theoretical framework. Spatial Moran index of autocorrelation, Spatial Lag Model(SLM) and Spatial Error Model(SEM) are used to analyze the star-rated hotels labor productivity of 31 provincial regions in China's Mainland based on the star-rated hotels statistical data of year 2016. The spatial correlation and spatial difference of the star-rated hotels labor productivity is discussed. This paper studies the impact of three factors on spatial characteristics of star-rated hotels labor productivity in China's Mainland. The econometric estimation results show that:(1) Star-rated hotels labor productivity present significant spatial dependence and spatial difference in China's Mainland.(2) The estimation results of Ordinary least Squares(OLS) are reliable.(3) The reliability of the results obtained by the Spatial Error Model(SEM) analysis is the highest, and has a stronger explanatory power to the spatial relationship of star-rated hotels labor productivity in China's Mainland. The average room occupancy rate has more influence on the labor productivity of the provincial star-rated hotels than the impact of capital and labor. 展开更多
关键词 Labor productivity Star-rated hotels Room occupancy rate Spatial econometric analysis China's Mainland
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Towards a new avenue for rapid synthesis of electrocatalytic electrodes via laser-induced hydrothermal reaction for water splitting
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作者 Yang Sha Menghui Zhu +6 位作者 Kun Huang Yang Zhang Francis Moissinac Zhizhou Zhang Dongxu Cheng Paul Mativenga Zhu Liu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期340-351,共12页
Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water splitting.To address these challenges,researchers are increasingly exploring ... Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water splitting.To address these challenges,researchers are increasingly exploring binder-free electrocatalytic integratedelectrodes (IEs) as an alternative to conventional powder-based electrode preparation methods,for the former is highly desirable to improve the catalytic activity and long-term stability for large-scale applications of electrocatalysts.Herein,we demonstrate a laser-inducedhydrothermal reaction (LIHR) technique to grow NiMoO4nanosheets on nickel foam,which is then calcined under H2/Ar mixed gases to prepare the IE IE-NiMo-LR.This electrode exhibits superior hydrogen evolution reaction performance,requiring overpotentials of 59,116 and143 mV to achieve current densities of 100,500 and 1000 mA·cm-2.During the 350 h chronopotentiometry test at current densities of 100 and 500 m A·cm-2,the overpotentialremains essentially unchanged.In addition,NiFe-layered double hydroxide grown on Ni foam is also fabricated with the same LIHR method and coupled with IE-NiMo-IR to achieve water splitting.This combination exhibits excellent durability under industrial current density.The energy consumption and production efficiency of the LIHR method are systematicallycompared with the conventional hydrothermal method.The LIHR method significantly improves the production rate by over 19 times,while consuming only 27.78%of the total energy required by conventional hydrothermal methods to achieve the same production. 展开更多
关键词 electrocatalytic electrode laser-induced hydrothermal reaction NiFe layered double hydroxides hydrogen evolution reaction water splitting energy consumption production rate
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The net primary productivity of Mid-Jurassic peatland and its control factors: Evidenced by the Ordos Basin 被引量:8
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作者 Wang Dongdong Yan Zhiming +2 位作者 Liu Haiyan Lv Dawei Hou Yijun 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第2期177-185,共9页
Using the large-scale thick 4# coal seam from the Mid-Jurassic in the southern Ordos Basin as an example, this paper studied the net primary productivity(NPP) level of the Mid-Jurassic peatland, and discussed its cont... Using the large-scale thick 4# coal seam from the Mid-Jurassic in the southern Ordos Basin as an example, this paper studied the net primary productivity(NPP) level of the Mid-Jurassic peatland, and discussed its control factors. Geophysical logging signals were used for a spectrum analysis to obtain the Milankovitch cycle parameters in coal seam. These were then used to calculate the accumulation rate of the residual carbon in 4# coal seam. The carbon loss can be calculated according to the density and residual carbon content of 4# coal seam. Then, the total carbon accumulation rate of the peatland was further derived, and the NPP of peatland was determined. The results show that the NPP of MidJurassic peatland is higher than that of Holocene at the same latitude. Comprehensive analysis indicates that the temperature, carbon dioxide and oxygen levels in atmosphere are the main control factors of the NPP of Mid-Jurassic peatland. 展开更多
关键词 Net primary productivity(NPP) PEATLAND MILANKOVITCH cycle Carbon accumulation rate Mid-Jurassic
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Physiological basis for the differences of productive capacity among tillers in winter wheat 被引量:7
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作者 XU Hai-cheng CAI Tie +1 位作者 WANG Zhen-lin HE Ming-rong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第10期1958-1970,共13页
The quality or structure of a wheat population is significantly affected by the compositions of tillers. Little has been known about the physiological basis for the differences of productive capacity among tillers. Tw... The quality or structure of a wheat population is significantly affected by the compositions of tillers. Little has been known about the physiological basis for the differences of productive capacity among tillers. Two winter wheat cultivars, Shannong 15(SN15) and Shannong 8355(SN8355), were used to investigate the differences of productive capacity among tillers and analyze the physiological mechanisms that determine the superior tiller group. Low-position tillers(early initiated tillers) had a higher yield per spike than high-position tillers(late initiated tillers) in both cultivars, which was due to their more grain number per spike, more fertile spikelet per spike, less sterile spikelet per spike and higher grain weight. According to cluster analysis, tillers of SN15 were classified into 2 groups: superior tiller group including main stem(0), the first primary tiller(I) and the second primary tiller(II); and inferior tiller group including the third primary tiller(III) and the first secondary tiller(I-p). Tillers of SN8355 were classified into 3 groups: superior tiller group(0 and I), intermediate tiller group(II and III) and inferior tiller group(I-p). In comparison with other tiller groups, the superior tiller group had higher photosynthetic rate of flag leaves, higher antioxidant enzyme(SOD, POD and CAT) activities and lower levels of lipid peroxidation in leaves, higher grain filling rate in both superior and inferior grains during grain filling, higher single-stem biological yield and larger single-stem economic coefficient. Correlation analysis showed that yield per spike was positively and significantly correlated with the flag leaf photosynthetic rate, grain filling rate, the antioxidant enzyme activities and soluble protein content(except for SN15 at 5 days post-anthesis(DPA)) of flag leaf, the single-stem biological yield, and the single-stem economic coefficient. Remarkable negative correlation was also found between yield per spike and MDA content of flag leaf. These results suggested that superior tiller group had stronger leaf photosynthetic capacity, more predominance in terms of grain filling, slower senescence rate, higher biological yield and larger economic coefficient, and therefore, showed greater productive capacity than other tiller groups. 展开更多
关键词 enzyme activities grain filling photosynthetic rate productive capacity TILLERS wheat(Triticum aestivum L.)
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The Effect of Toxic Sulfide Exposure on Oxygen Consumption and Oxidation Products in Urechis unicinctus(Echiura:Urechidae) 被引量:12
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作者 WANG Sifeng ZHANG Zhifeng +2 位作者 CUI He KANG Kyoung Ho MA Zhuojun 《Journal of Ocean University of China》 SCIE CAS 2010年第2期157-161,共5页
To investigate sulfide detoxification in Urech& unicinctus, oxygen consumption rate and sulfide detoxification products were analyzed during sulfide exposure under controlled laboratory conditions. The results showed... To investigate sulfide detoxification in Urech& unicinctus, oxygen consumption rate and sulfide detoxification products were analyzed during sulfide exposure under controlled laboratory conditions. The results showed that oxygen consumption rates were elevated significantly during 3 h sulfide exposure compared to the control (P〈0.05). The concentration of sulfite in body wall and hindgut of experimental worms increased significantly (P〈0.05) when exposed to 50 μmolL^-1 sulfide, reached a maximum at 24 h and then decreased. Similar result was observed in worms exposed to 150 μmolL^-1 sulfide except that sulfite concentration reached a maximum at 12 h. Contents of thiosulfate in body wall and hindgut of U. unicinctus exposed to sulfide were also significantly higher than that of the control without sulfide exposure. In conclusion, during short-time sulfide exposure U. unicinctus may raise oxygen consumption to detoxify toxic sulfide into sulfite and thiosulfate. Sulfide detoxification was restrained when the exposure time was prolonged or sulfide concentration was increased, which was indicated by decrease of sulfite, the intermediate product of sulfide detoxification. 展开更多
关键词 Urechis unicinctus SULFIDE DETOXIFICATION oxygen consumption rate productS
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Application of first order rate kinetics to explain changes in bloom toxicity——the importance of understanding cell toxin quotas 被引量:2
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作者 Philip T.ORR Anusuya WILLIS Michele A.BURFORD 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第4期1063-1074,共12页
Cyanobacteria are oxygenic photosynthetic Gram-negative bacteria that can form potentially toxic blooms in eutrophic and slow flowing aquatic ecosystems. Bloom toxicity varies spatially and temporally, but understandi... Cyanobacteria are oxygenic photosynthetic Gram-negative bacteria that can form potentially toxic blooms in eutrophic and slow flowing aquatic ecosystems. Bloom toxicity varies spatially and temporally, but understanding the mechanisms that drive these changes remains largely a mystery. Changes in bloom toxicity may result from changes in intracellular toxin pool sizes of cyanotoxins with differing molecular toxicities, and/or from changes in the cell concentrations of toxic and non-toxic cyanobacterial species or strains within bloom populations. We show here how first-order rate kinetics at the cellular level can be used to explain how environmental conditions drive changes in bloom toxicity at the ecological level. First order rate constants can be calculated for changes in cell concentration( μ_c : specific cell division rate) or the volumetric biomass concentration( μ_g : specific growth rate) between short time intervals throughout the cell cycle. Similar first order rate constants can be calculated for changes in nett volumetric cyanotoxin concentration( μ_(tox) : specific cyanotoxin production rate) over similar time intervals. How μ_c(or μ_g) covaries with μ tox over the cell cycle shows conclusively when cyanotoxins are being produced and metabolised, and how the toxicity of cells change in response to environment stressors. When μ_(tox)/μ_c >1, cyanotoxin cell quotas increase and individual cells become more toxic because the nett cyanotoxin production rate is higher than the cell division rate. When μ_(tox)/μ_c =1, cell cyanotoxin quotas remains fixed because the nett cyanotoxin production rate matches the cell division rate. When μ_(tox)/μ_c <1, the cyanotoxin cell quota decreases because either the nett cyanotoxin production rate is lower than the cell division rate, or metabolic breakdown and/or secretion of cyanotoxins is occurring. These fundamental equations describe cyanotoxin metabolism dynamics at the cellular level and provide the necessary physiological background to understand how environmental stressors drive changes in bloom toxicity. 展开更多
关键词 cyanotoxin production dynamics first order rate kinetics CYANOBACTERIA
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Positive Research on China’s Economic Growth Quality——Analyze the Fluctuating Situation of the Factor Input and Aggregative Productivity 被引量:2
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作者 LiBtanhua 《Ecological Economy》 2005年第1期98-105,共8页
To analyze China’s fluctuating situation of the factor input and aggregative productivity is not only the main method to seek the source of the economic growth but also the main way to weigh the level of economic gro... To analyze China’s fluctuating situation of the factor input and aggregative productivity is not only the main method to seek the source of the economic growth but also the main way to weigh the level of economic growth quality.As to economic growth ofa country,the improvementofthe productivity is extremely important.The growth of the output can be realized through two kinds of ways: increasing the quantity of factor input of or improving the efficiency of the input and output.There fore, the level of economic growth quality does not mainly depend on the amount of invested factor,but the importance of improving the productivity since resources are rare. The relative improvement of efficiency in use of the invested factor marks the economic growing quality.So,in order to understand the economic growth quality of China to some extent, it must analyze Chinese factor input and aggregative productivity. This is the main topic that this text will be probed into. 展开更多
关键词 factor input contribution rate of factors aggregative productivity quality of increasing
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