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An Empirical Study on Rural Economic Growth in Hubei Province Based on New C-D Production Function 被引量:2
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作者 Yi WEN Minghong CAO 《Asian Agricultural Research》 2016年第10期6-8,12,共4页
Human capital is becoming a major driving force of promoting economic growth and social development. Hubei Province as a large agricultural province is significantly affected by the human capital. The paper selects th... Human capital is becoming a major driving force of promoting economic growth and social development. Hubei Province as a large agricultural province is significantly affected by the human capital. The paper selects the correlation data about rural economic growth in Hubei Province as samples to analyze the contribution of physical capital and human capital to rural economic growth by the new C-D function and SPSS22. 0. The results show that the effect of the elasticity of human capital is greater than that of physical capital in rural economic development; the high quality rural human capital storage and the average years of schooling of rural labor force will increase the net income of rural household. Therefore,we should not only increase input of physical capital but also increase the input of human capital to raise the level of human capital in rural areas and promote sustainable development of rural economy. 展开更多
关键词 New c-d function Human capital Physical capital
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Consistency of Water Production Function Models of Two Crops 被引量:1
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作者 樊鹏 王莹 +1 位作者 杨青伟 杨喜会 《Agricultural Science & Technology》 CAS 2016年第1期12-14,共3页
On basis of test information, the research performed analysis on water production function models of two crops, which indicated that water model of crops in whole growth stage and water model of crops indifferent grow... On basis of test information, the research performed analysis on water production function models of two crops, which indicated that water model of crops in whole growth stage and water model of crops indifferent growth stages have consistency as well as differences, providing references for optimization of irrigation water. Meanwhile, the research analyzed the deficiency of optimization on irrigation water for crops just by Jensen model. 展开更多
关键词 Water production function Parabolic model Jensen model CONSISTENCY
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Analysis on Input-Output in Rice Cultivation Based on Cobb-Douglas Production Function 被引量:2
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作者 高雷 《Agricultural Science & Technology》 CAS 2012年第4期716-718,共3页
[Objective] To analyze the input and output in rice cultivation based on CD function. [Method] Based on the input factors, Cobb-Douglas production (CD) function was used to do the quantitative analysis on the input-... [Objective] To analyze the input and output in rice cultivation based on CD function. [Method] Based on the input factors, Cobb-Douglas production (CD) function was used to do the quantitative analysis on the input-output in rice production with rice growers as the objective. [Result] Considering the substitution effect of labor in- put and capital input, under the same technical conditions, the effect of increasing labor input on the rice production in per 667 m2 was negative, based on which 2 pieces of policy suggestions were put forward to promote the transfer of surplus la- bor force of rice growers and ensure the capital supply for rice production. [Conclusion] This study laid the foundation for the realization of reasonable allocation of rice production resources. 展开更多
关键词 Cobb-Douglas production function Rice cultivation INPUT OUTPUT
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Association of polymorphisms of Nramp1 gene with immune function and production performance of large white pig 被引量:12
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作者 Hongmei Wu Duxue Cheng Lixian Wang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第2期91-95,共5页
The present research was designed to study the association of polymorphism of natural resistance-associated macrophage proteinl (Nrampl) with some immune function and the production performance in Large White pig. T... The present research was designed to study the association of polymorphism of natural resistance-associated macrophage proteinl (Nrampl) with some immune function and the production performance in Large White pig. The PCR-RFLP technique was applied to analyze the correlation between the polymorphisms of Nrampl gene and immune function [value of Polymorphonuclear Leukocytes (PMN) obtained by Nitroblue Tetrazolium (NBT) Reduction and effect of Cytotoxin in Monocyte] and production performance in 165 Large White pigs. The results showed that there was one Nde I restriction locus in Large White pig, and both values of PMN by NBT Reduction and effect of Cytotoxin in Monocyte in genotype BB were higher than those in genotype AB (P〈0.05). Simultaneously, the weight of 180-day-old pigs with genotype BB was higher than that with genotype AB (P〈0.05). The results indicated that there was a significant correlation between different genotypes of Nrampl gene and Immune function and production performance, and it can be regarded as a candidate gene of disease resistance. All these results provide valuable reference to further studies of pig disease resistance. 展开更多
关键词 Large White pig Nrampl gene immune function production performance
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Biological function of resveratrol and its application in animal production:a review 被引量:16
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作者 Qingwei Meng Jiawei Li +1 位作者 Chunsheng Wang Anshan Shan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期864-886,共23页
With the prohibition of antibiotics in feed,plant functional substances have been widely studied as feed additives.Resveratrol,a natural stilbene,and a non-flavonoid polyphenol found in plants,possesses antioxidant,an... With the prohibition of antibiotics in feed,plant functional substances have been widely studied as feed additives.Resveratrol,a natural stilbene,and a non-flavonoid polyphenol found in plants,possesses antioxidant,anti-inflammatory,and metabolic regulatory features.Resveratrol generated intense scientific and public interest,primarily due to its widely reported ability to prevent cancer,delay aging and alleviate related metabolic diseases.Recently,resveratrol has been studied and applied as a feed additive in animal production.This review focuses on the outline of the absorption and metabolism and biological functions of resveratrol and summarizes the application of dietary resveratrol in animal production up to the present,including pigs,poultry,and ruminants.In pigs,dietary resveratrol improved intestinal health,mitochondrial function,meat quality,and more.In poultry,studies have shown that dietary resveratrol improves growth performance and meat and egg quality and alleviates heat stress induced adverse effects.There are few studies on dietary resveratrol in ruminants;however previous studies have indicated that dietary resveratrol increases nutrient digestibility and reduces methane emissions in sheep.It is hoped that this review could provide a specific theoretical basis and research ideas for the research and application of resveratrol. 展开更多
关键词 Animal production Biological function HEALTH PIGS POULTRY RESVERATROL RUMINANTS
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Saline Water Irrigation Scheduling Through a Crop-Water-Salinity Production Function and a Soil-Water-Salinity Dynamic Model 被引量:16
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作者 WANG Yang-Ren KANG Shao-Zhong +2 位作者 LI Fu-Sheng ZHANG Lu ZHANG Jian-Hua 《Pedosphere》 SCIE CAS CSCD 2007年第3期303-317,共15页
Using a crop-water-salinity production function and a soil-water-salinity dynamic model, optimal irrigation scheduling was developed to maximize net return per irrigated area. Plot and field experiments were used to o... Using a crop-water-salinity production function and a soil-water-salinity dynamic model, optimal irrigation scheduling was developed to maximize net return per irrigated area. Plot and field experiments were used to obtain the crop water sensitivity index, the salinity sensitivity index, and other parameters. Using data collected during 35 years to calculate the 10-day mean precipitation and evaporation, the variation in soil salinity concentrations and in the yields of winter wheat and cotton were simulated for 49 irrigation scheduling that were combined from 7 irrigation schemes over 3 irrigation dates and 7 salinity concentrations of saline irrigation water (fresh water and 6 levels of saline water). Comparison of predicted results with irrigation data obtained from a large area of the field showed that the model was valid and reliable. Based on the analysis of the investment cost of the irrigation that employed deep tube wells or shallow tube wells, a saline water irrigation schedule and a corresponding strategy for groundwater development and utilization were proposed. For wheat or cotton, if the salinity concentration was higher than 7.0 g L-1 in groundwater, irrigation was needed with only fresh water; if about 5.0 g L-1, irrigation was required twice with fresh water and once with saline water; and if not higher than 3.0 g L-1, irrigation could be solely with saline water. 展开更多
关键词 crop-water-salinity production function irrigation scheduling saline water irrigation water-salinity dy- namic model
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An Application of Non–Linear Cobb-Douglas Production Function to Selected Manufacturing Industries in Bangladesh 被引量:3
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作者 Md. Moyazzem Hossain Ajit Kumar Majumder Tapati Basak 《Open Journal of Statistics》 2012年第4期460-468,共9页
Recently, businessmen as well as industrialists are very much concerned about the theory of firm in order to make correct decisions regarding what items, how much and how to produce them. All these decisions are direc... Recently, businessmen as well as industrialists are very much concerned about the theory of firm in order to make correct decisions regarding what items, how much and how to produce them. All these decisions are directly related with the cost considerations and market situations where the firm is to be operated. In this regard, this paper should be helpful in suggesting the most suitable functional form of production process for the major manufacturing industries in Bangladesh. This paper considers Cobb-Douglas (C-D) production function with additive error and multiplicative error term. The main purpose of this paper is to select the appropriate Cobb-Douglas production model for measuring the production process of some selected manufacturing industries in Bangladesh. We use different model selection criteria to compare the Cobb-Douglas production function with additive error term to Cobb-Douglas production function with multiplicative error term. Finally, we estimate the parameters of the production function by using optimization subroutine. 展开更多
关键词 COBB-DOUGLAS production function NEWTON-RAPHSON Method MANUFACTURING INDUSTRY BANGLADESH
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Well production optimization using streamline features-based objective function and Bayesian adaptive direct search algorithm 被引量:4
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作者 Qi-Hong Feng Shan-Shan Li +2 位作者 Xian-Min Zhang Xiao-Fei Gao Ji-Hui Ni 《Petroleum Science》 SCIE CAS CSCD 2022年第6期2879-2894,共16页
Well production optimization is a complex and time-consuming task in the oilfield development.The combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well production.T... Well production optimization is a complex and time-consuming task in the oilfield development.The combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well production.This method spends most of computing time in objective function evaluation by reservoir numerical simulator which limits its optimization efficiency.To improve optimization efficiency,a well production optimization method using streamline features-based objective function and Bayesian adaptive direct search optimization(BADS)algorithm is established.This new objective function,which represents the water flooding potential,is extracted from streamline features.It only needs to call the streamline simulator to run one time step,instead of calling the simulator to calculate the target value at the end of development,which greatly reduces the running time of the simulator.Then the well production optimization model is established and solved by the BADS algorithm.The feasibility of the new objective function and the efficiency of this optimization method are verified by three examples.Results demonstrate that the new objective function is positively correlated with the cumulative oil production.And the BADS algorithm is superior to other common algorithms in convergence speed,solution stability and optimization accuracy.Besides,this method can significantly accelerate the speed of well production optimization process compared with the objective function calculated by other conventional methods.It can provide a more effective basis for determining the optimal well production for actual oilfield development. 展开更多
关键词 Well production Optimization efficiency Streamline simulation Streamline feature Objective function Bayesian adaptive direct search algorithm
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Grain production space reconstruction and land system function tradeoffs in China 被引量:4
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作者 Fei Li Zhangxuan Qin +4 位作者 Xiaolin Liu Zehui Chen Xiaoli Wei Qiumeng Zhang Min Lei 《Geography and Sustainability》 2021年第1期22-30,共9页
Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural deve... Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural development space,and ecological service space.Exploring tradeoffs between land system functions caused by grain produc-tion space reconstruction was particularly important for ensuring food security,promoting the construction of ecological civilization,and achieving sustainable development.Therefore,this study identified four relationships of land system functions during the process of grain production space reconstruction(1980-2018)in China by using Set Pair Analysis.Research results showed that the reconstruction of grain production space was achieved mainly through three pathways:Grain for Green,deforestation and reclamation,and urban expansion.Generally,ecological service had spatial negative correlation with grain production,economic development and population carrying capacity(P<0.01),but grain production,economic development and population carrying capacity were positively correlated with each other(P<0.01).In the process of grain production space reconstruction,eco-logical services and economic development,ecological services and population carrying capacity had all shown inverse synergies;there was a tradeoffbetween grain production and ecological services,a codirectional tradeoffbetween grain production and economic development,but a strong synergy between economic development and population carrying capacity.However,the functions of land systems only appeared as synergies or tradeoffs,and there were no inverse synergies and codirectional tradeoffs in the separate processes of Grain for Green,deforestation and reclamation,and urban expansion.It can be concluded that the relationships between land system functions were relatively simple in a single process,but it became complex and diverse when multiple processes were integrated for system analysis. 展开更多
关键词 Land system function TRADEOFFS SYNERGY Grain production space reconstruction Set Pair Analysis
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Study of Chinese Economic "Growth Drag" Caused by Land Resource in the Perspective of the Modified Two-Level CES Production Function 被引量:2
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作者 Yang Yang Wu Cifang 《Chinese Journal of Population,Resources and Environment》 2012年第4期39-43,共5页
The purpose of the study is to measure the "growth drag" according to the characteristic of Chinese land resource.Romer model (2001) holds that every country is inevitably affected by the "growth drag&q... The purpose of the study is to measure the "growth drag" according to the characteristic of Chinese land resource.Romer model (2001) holds that every country is inevitably affected by the "growth drag" due to the limitation of land resource.So it's of profound strategic significance to measure the "growth drag" according to the character of Chinese land resource.Modified two-level CES production function was employed,and this paper modified the hypothesis of the model.The result indicates that the limitation of Chinese land resource casts shadow over the economic development of China,and the growth rate is 0.4618% lower than that without the limitation of land resource.Through implementing the land resource protection policy along with the technology improvement and the substitute effect of other factors to the land resource,China will keep a steady and balanced economic growth. 展开更多
关键词 growth drag modified two-level CES production function land resource economic growth China
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Application of Non-Linear Cobb-Douglas Production Function with Autocorrelation Problem to Selected Manufacturing Industries in Bangladesh 被引量:1
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作者 Md. Moyazzem Hossain Tapati Basak Ajit Kumar Majumder 《Open Journal of Statistics》 2013年第3期173-178,共6页
In developing counties, efficiency of economic development has been determined by the analysis of industrial production. An examination of the characteristic of industrial sector is an essential aspect of growth studi... In developing counties, efficiency of economic development has been determined by the analysis of industrial production. An examination of the characteristic of industrial sector is an essential aspect of growth studies. The growth of a country can be measured by Gross Domestic Product (GDP). GDP is substantially affected by the industrial output. Industrial gross output is mainly a function of capital and labor input. If the effect of labor and capital input to output is at a satisfactory level in an industry or in a group of industries, then industrial investment will increase. As a result, the number of industries will increase, which will directly affect GDP and also will decrease the unemployment rate. This is why, industrial input-output relationship is so important for any industry as well as for the overall industrial sector of a country. To forecast the production of a firm is necessary to identify the appropriate model. MD. M. Hossain et al. [1] have shown that Cobb-Douglas production function with additive errors was more suitable for some selected manufacturing industries in Bangladesh. The main purpose of this paper is to detect the autocorrelation problem of Cobb-Douglas production model with additive errors. The result shows that autocorrelation is presented in some manufacturing industries. Finally, this paper removes the autocorrelation problem and re-estimates the parameters of the Cobb- Douglas production function with additive errors. 展开更多
关键词 COBB-DOUGLAS production function AUTOCORRELATION Manufacturing INDUSTRY BANGLADESH
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Precisely decorating CdS on Zr-MOFs through pore functionalization strategy: A highly efficient photocatalyst for H2 production 被引量:1
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作者 Haijun Hu Kailai Zhang +6 位作者 Ge Yan Litong Shi Baohua Jia Hongwei Huang Yu Zhang Xiaodong Sun Tianyi Ma 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第9期2332-2341,共10页
Different materials,such as metal sulphides,are often combined with metal‐organic frameworks(MOFs)to develop multi‐functional composites and improve their photocatalytic properties.However,the high interfacial energ... Different materials,such as metal sulphides,are often combined with metal‐organic frameworks(MOFs)to develop multi‐functional composites and improve their photocatalytic properties.However,the high interfacial energy barrier limits the formation and nano‐assembly of the heterogeneous junctions between MOFs and metal sulphides.Herein,the heterostructured Zr‐MOF‐S@CdS are successfully constructed through a sequential synthesis method,in which the mesoporous Zr‐MOF are firstly decorated with thioglycolic acid through pore functionalization,and followed by the S^(2-)anion exchange process resulting in the surface close attached growth of CdS onto Zr‐MOF‐S materials.Due to the presence of molecules linkers,the CdS can be precisely decorated onto Zr‐MOF‐S without aggregation,which can provide more active sites.Moreover,the intimate connections and the suitable band structures between two materials can also facilitate the photogenerated electron‐hole pairs separation.Therefore,the resulting Zr‐MOF‐S@CdS with appropriate ratio exhibits high photocatalytic activity for water reduction,in which the H_(2) evolution rate can reach up to 1861.7μmol·g^(‒1)·h^(‒1),4.5 times higher than pure CdS and 2.3 times higher than of Zr‐MOF/CdS,respectively.Considering the promising future of MOF‐based photocatalysts,this work may provide an avenue for the further design and synthesis MOF‐based composite photocatalysts for efficient H_(2) evolution. 展开更多
关键词 Zr-MOF Pore functionalization Photocatalytic H2 production Molecular linker Junction
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Public-Key Function-Private Inner-Product Predicate Encryption from Pairings
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作者 WAN Ming WANG Geng GU Da-Wu 《密码学报(中英文)》 北大核心 2025年第1期227-246,共20页
This study constructs a function-private inner-product predicate encryption(FP-IPPE)and achieves standard enhanced function privacy.The enhanced function privacy guarantees that a predicate secret key skf reveals noth... This study constructs a function-private inner-product predicate encryption(FP-IPPE)and achieves standard enhanced function privacy.The enhanced function privacy guarantees that a predicate secret key skf reveals nothing about the predicate f,as long as f is drawn from an evasive distribution with sufficient entropy.The proposed scheme extends the group-based public-key function-private predicate encryption(FP-PE)for“small superset predicates”proposed by Bartusek et al.(Asiacrypt 19),to the setting of inner-product predicates.This is the first construction of public-key FP-PE with enhanced function privacy security beyond the equality predicates,which is previously proposed by Boneh et al.(CRYPTO 13).The proposed construction relies on bilinear groups,and the security is proved in the generic bilinear group model. 展开更多
关键词 predicate encryption function privacy inner product generic group model
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A study on the bioenergy crop production function of land use in China 被引量:2
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作者 ZHANG Kun YU Yao +1 位作者 BAO Chun-hong WANG Tao 《Ecological Economy》 2010年第4期407-414,共8页
Based on the analysis of the bioenergy crop production function of land use,combined with the status quo of Chinese land use,the cultivation of energy plants and the bioenergy crop production function of land use had ... Based on the analysis of the bioenergy crop production function of land use,combined with the status quo of Chinese land use,the cultivation of energy plants and the bioenergy crop production function of land use had been analyzes and discusses in this paper.Results show that there were a lot of unused lands and marginal lands which can be planted bioenergy crops to perform the bioenergy crop production function of land use with great potentials;and currently there were no food production problems.Therefore,it was very important for China to emphasize bioenergy crops planting in order to fully use land resources in our country,moderate the energy crisis and increase peasants' income. 展开更多
关键词 Land use Bioenergy crop production function of land use BIOENERGY Bioenergy crops Increase of peasants' income
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Natural plant polyphenols contribute to the ecological and healthy swine production
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作者 Huadi Mei Yuanfei Li +1 位作者 Shusong Wu Jianhua He 《Journal of Animal Science and Biotechnology》 2025年第2期471-496,共26页
The absence of trace amounts of natural bioactive compounds with important biological activities in traditional dietary models for global farm animals,coupled with an incomplete theoretical system for animal nutrition... The absence of trace amounts of natural bioactive compounds with important biological activities in traditional dietary models for global farm animals,coupled with an incomplete theoretical system for animal nutrition,has led to unbalanced and inadequate animal nutrition.This deficiency has adversely impacted animal health and the ecological environment,presenting formidable challenges to the advancement of the swine breeding industry in various countries around the world toward high-quality development.Recently,due to the ban of antibiotics for growth promotion in swine diets,botanical active compounds have been extensively investigated as feed additives.Polyphenols represent a broad group of plant secondary metabolites.They are natural,non-toxic,pollution-free,and highly reproducible compounds that have a wide range of physiological functions,such as antioxidant,anti-inflammatory,immunomodulatory,antiviral,antibacterial,and metabolic activities.Accordingly,polyphenols have been widely studied and used as feed additives in swine production.This review summarizes the structural characteristics,classification,current application situation,general properties of polyphenols,and the latest research advances on their use in swine production.Additionally,the research and application bottlenecks and future development of plant polyphenols in the animal feed industry are reviewed and prospected.This review aims to stimulate the in-depth study of natural plant polyphenols and the research and development of related products in order to promote the green,healthy,and high-quality development of swine production,while also providing ideas for the innovation and development in the theoretical system of animal nutrition. 展开更多
关键词 HEALTH Physiological function POLYPHENOLS production performance SWINE
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Quantifying production rates of tropical granitic regolith in Hainan Island,south China:A multi-stage U-series disequilibrium study
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作者 Guodong Jia Xu Yvon Zhang +4 位作者 François Chabaux Eric Pelt Zhiqi Zhao Sheng Xu Congqiang Liu 《Geoscience Frontiers》 2025年第3期301-317,共17页
Regolith,widely distributed on the Earth’s surface,constitutes a significant compartment of the Critical Zone,resulting from intricate interactions among the atmosphere,lithosphere,hydrosphere,and biosphere.Regolith ... Regolith,widely distributed on the Earth’s surface,constitutes a significant compartment of the Critical Zone,resulting from intricate interactions among the atmosphere,lithosphere,hydrosphere,and biosphere.Regolith formation critically influences nutrient release,soil production,and long-term climate regulation.Regolith development is governed by two primary processes:production and denudation.An urgent need exists to comprehensively understand these processes to refine our understanding of Critical Zone functions.This study investigates an in-situ regolith profile developed on granitic bedrock from a tropical region(Sanya,China).We conducted geochemical analyses,encompassing major,trace elements and mineralogical compositions as well as U-series isotopes,and applied the U-series disequilibrium method to investigate the formation history of this profile.Alternatively,dividing the regolith profile into sub-weathering zones provides a better explanation for the geochemical results,and a multi-stage model based on this subdivision effectively interprets the evolution of deep regolith.Utilizing this multi-stage model,regolith production rates is derived from the“gain and loss”model,ranging from 1.27±0.03 to 42.42±24.24 m/Ma.The production rates first increase from surface until a maximum rate is reached at the depth of∼160 cm and then decrease at further deeper horizons along the depth profile,and the variation of production rates follows a so-called“humped function”.This pioneering investigation into regolith production rates in the Chinese tropical region indicates that(1)the studied profile deviates from a steady state compared to the denudation rate derived from cosmogenic nuclides(^(10)Be_in-situ);(2)subdividing the deep profile based on geochemical data and U-series isotopic activity ratios is imperative for accurately determining regolith production rates;and(3)the combination of U-series disequilibrium and cosmogenic nuclides robustly evaluates the quantitative evolution state of regolith over long time scales. 展开更多
关键词 U-series isotopes Granitic regolith profile production rate Humped function Critical Zone WEATHERING
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The Estimation Methods for Agricultural Surplus Labor Based on Stochastic Frontier Production Function 被引量:9
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作者 Chaozhou LU Yanfen LUO 《Asian Agricultural Research》 2014年第6期61-65,共5页
The existing calculation methods for the number of agricultural surplus labor have a common flaw,that is,they can not reflect the impact of technical efficiency changes in agricultural production on the surplus labor.... The existing calculation methods for the number of agricultural surplus labor have a common flaw,that is,they can not reflect the impact of technical efficiency changes in agricultural production on the surplus labor. Based on the basic principle of stochastic frontier production function,this paper calculates the agricultural production technical efficiency of various provinces,and selects the province with the highest technical efficiency to assume that its agricultural labor is fully utilized,and there is no agricultural surplus labor. With the ratio of agricultural labor number to agricultural output value in this province as a reference,this paper calculates the number of agricultural surplus labor in other provinces. This calculation method makes up for the shortcomings of the existing calculation methods; it reflects the relationship between the number of agricultural surplus labor and production technical efficiency. 展开更多
关键词 AGRICULTURAL SURPLUS LABOR STOCHASTIC FRONTIER PRO
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Few-shot learning for screening 2D Ga_(2)CoS_(4-x) supported single-atom catalysts for hydrogen production
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作者 Nabil Khossossi Poulumi Dey 《Journal of Energy Chemistry》 2025年第1期665-673,共9页
Hydrogen generation and related energy applications heavily rely on the hydrogen evolution reaction(HER),which faces challenges of slow kinetics and high overpotential.Efficient electrocatalysts,particularly single-at... Hydrogen generation and related energy applications heavily rely on the hydrogen evolution reaction(HER),which faces challenges of slow kinetics and high overpotential.Efficient electrocatalysts,particularly single-atom catalysts (SACs) on two-dimensional (2D) materials,are essential.This study presents a few-shot machine learning (ML) assisted high-throughput screening of 2D septuple-atomic-layer Ga_(2)CoS_(4-x)supported SACs to predict HER catalytic activity.Initially,density functional theory (DFT)calculations showed that 2D Ga_(2)CoS4is inactive for HER.However,defective Ga_(2)CoS_(4-x)(x=0–0.25)monolayers exhibit excellent HER activity due to surface sulfur vacancies (SVs),with predicted overpotentials (0–60 mV) comparable to or lower than commercial Pt/C,which typically exhibits an overpotential of around 50 m V in the acidic electrolyte,when the concentration of surface SV is lower than 8.3%.SVs generate spin-polarized states near the Fermi level,making them effective HER sites.We demonstrate ML-accelerated HER overpotential predictions for all transition metal SACs on 2D Ga_(2)CoS_(4-x).Using DFT data from 18 SACs,an ML model with high prediction accuracy and reduced computation time was developed.An intrinsic descriptor linking SAC atomic properties to HER overpotential was identified.This study thus provides a framework for screening SACs on 2D materials,enhancing catalyst design. 展开更多
关键词 Hydrogen production ELECTROCATALYST 2D material Density functional theory Machine learning Surface sulfur vacancy
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Effects of Lactobacillus Microecologics on Production Performance, Immune Function and Intestinal Microflora of Egg Chicks
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作者 Xiao Jianshe Pan Huiqing Zhang Yanda 《Animal Husbandry and Feed Science》 CAS 2019年第3期103-106,共4页
[Objective]The paper was to study the effects of lactobacillus microecologics on production performance,immune function and intestinal microflora of egg chicks.[Method]Totally 18001-day-old chicks of Hyline brown were... [Objective]The paper was to study the effects of lactobacillus microecologics on production performance,immune function and intestinal microflora of egg chicks.[Method]Totally 18001-day-old chicks of Hyline brown were randomly divided into three groups,four repeats each group and 150 chicks each repeat.The chicks in control group were supplied with basic diet,and those in experimental groups I and II were supplied with the basic diet added with 100 and 150 g/t microecologics,respectively.[Result]Compared with the control group,the daily gain of egg chicks in experimental group II after 7 weeks was increased by 3.67%(P<0.05),and the feed conversion ratio was significantly reduced by 0.05(P<0.05);the thymus indexes in experimental groups I and II were significantly improved by 4.95%and 5.94%(P<0.05),and the spleen indexes were significantly improved by 3.32% and 4.36% compared with the control group(P<0.05).The index of bursa of fabricius in experimental group II was extremely improved by 9.66%compared with the control group(P<0.01).Meantime,experimental group II extremely improved the number of living lactobacillus in caecum of egg chicks(P<0.01),and extremely reduced the number of Escherichia coli in caecum(P<0.01).[Conclusion]Lactobacillus microecologics are beneficial to the improvement of production performance,immune function and intestinal flora of egg chicks.The optimal addition amount in the feed of chicks is 150 g/t. 展开更多
关键词 LACTOBACILLUS microecologics EGG CHICK production performance Immune function Intestinal MICROFLORA
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Efficient Frontier via Production Functions and Mechanization
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作者 Hideki Nakamura 《American Journal of Operations Research》 2017年第1期56-63,共8页
This study attempts to reconcile data envelopment analysis (DEA) with the production function approach in economics. We examine not only the inputs of capital and labor, but also the ranges of these inputs in producti... This study attempts to reconcile data envelopment analysis (DEA) with the production function approach in economics. We examine not only the inputs of capital and labor, but also the ranges of these inputs in production process steps, and endogenously derive a Leontief production function. The Leontief production functions shift northeasterly owing to mechanization, which is the replacement of labor inputs by capital inputs in some steps. Consequently, we describe the efficient frontier as the convex hull of the Leontief production functions. Furthermore, we consider the possibility of efficient production below the efficient frontier. 展开更多
关键词 production Process STEPS Leontief production function MECHANIZATION EFFICIENT FRONTIER production below the EFFICIENT FRONTIER
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