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Valorization of Camellia oleifera oil processing byproducts to value-added chemicals and biobased materials: A critical review 被引量:3
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作者 Xudong Liu Yiying Wu +11 位作者 Yang Gao Zhicheng Jiang Zicheng Zhao Wenquan Zeng Mingyu Xie Sisi Liu Rukuan Liu Yan Chao Suli Nie Aihua Zhang Changzhu Li Zhihong Xiao 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期28-53,共26页
The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,bi... The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,birch,etc.),Camellia wastes contain diverse bioactive substances in addition to the abundant lignocellulosic components,and thus,the biorefinery utilization of C.oleifera processing byproducts involves complicated processing technologies.This reviewfirst summarizes various technologies for extracting and converting the main components in C.oleifera oil processing byproducts into value-added chemicals and biobased materials,as well as their potential applications.Microwave,ultrasound,and Soxhlet extractions are compared for the extraction of functional bioactive components(tannin,flavonoid,saponin,etc.),while solvothermal conversion and pyrolysis are discussed for the conversion of lignocellulosic components into value-added chemicals.The application areas of these chemicals according to their properties are introduced in detail,including utilizing antioxidant and anti-in-flammatory properties of the bioactive substances for the specific application,as well as drop-in chemicals for the substitution of unrenewable fossil fuel-derived products.In addition to chemical production,biochar fabricated from COS and its applications in thefields of adsorption,supercapacitor,soil remediation and wood composites are comprehensively reviewed and discussed.Finally,based on the compositions and structural characteristics of C.oleifera byproducts,the development of full-component valorization strategies and the expansion of the appli-cationfields are proposed. 展开更多
关键词 Camellia oleifera shell Camellia oleifera cake value-added chemicals Bioactive components Biobased materials
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Upcycling plastic wastes into value-added products via electrocatalysis and photoelectrocatalysis 被引量:1
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作者 Sungsoon Kim Dongjae Kong +1 位作者 Xiaolin Zheng Jong Hyeok Park 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期522-541,共20页
Plastic,renowned for its versatility,durability,and cost-effectiveness,is indispensable in modern society.Nevertheless,the annual production of nearly 400 million tons of plastic,coupled with a recycling rate of only ... Plastic,renowned for its versatility,durability,and cost-effectiveness,is indispensable in modern society.Nevertheless,the annual production of nearly 400 million tons of plastic,coupled with a recycling rate of only 9%,has led to a monumental environmental crisis.Plastic recycling has emerged as a vital response to this crisis,offering sustainable solutions to mitigate its environmental impact.Among these recycling efforts,plastic upcycling has garnered attention,which elevates discarded plastics into higher-value products.Here,electrocatalytic and photoelectrocatalytic treatments stand at the forefront of advanced plastic upcycling.Electrocatalytic or photoelectrocatalytic treatments involve chemical reactions that facilitate electron transfer through the electrode/electrolyte interface,driven by electrical or solar energy,respectively.These methods enable precise control of chemical reactions,harnessing potential,current density,or light to yield valuable chemical products.This review explores recent progress in plastic upcycling through electrocatalytic and photoelectrocatalytic pathways,offering promising solutions to the plastic waste crisis and advancing sustainability in the plastics industry. 展开更多
关键词 Plastic upcycling Electrocatalytic reaction Photoelectrocatalytic reaction value-added product
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Influence of Pt/Ru anodic ratio on the valorization of ethanol by PEM electrocatalytic reforming towards value-added products 被引量:2
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作者 Alberto Rodriguez-Gomez Fernando Dorado +1 位作者 Antonio de Lucas-Consuegra Ana Raquel de la Osa 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期264-275,共12页
The ethanol electro-reforming process was studied over PtRu/C catalysts synthesized by the modified polyol method with different compositions.In particular,this work reports the influence of anodic Pt:Ru ratio(5:1,2:1... The ethanol electro-reforming process was studied over PtRu/C catalysts synthesized by the modified polyol method with different compositions.In particular,this work reports the influence of anodic Pt:Ru ratio(5:1,2:1 and 1:2)on the organic product distribution(acetaldehyde,acetic acid and ethyl acetate)and pure hydrogen generation at different current densities operation levels.Physicochemical characterization of the catalysts was made by X-ray diffraction(XRD),temperature-programmed reduction(TPR)and N_(2) adsorption-desorption measurements.XRD patterns showed that Ru is introduced into the Pt structure,forming an alloy between both metals.Also,the degree of alloy was higher by increasing the Ru amounts.From TPR profiles Pt was found to be properly reduced while Ru was both in metallic state and forming RuO2.The electrochemical behaviour of each catalyst towards ethanol electroreforming process was investigated through electrochemical techniques in a half cell and a single proton exchange membrane(PEM)cell systems.An intermediate Pt:Ru ratio was found to result in high current density and electrochemical surface area(ECSA)values along with lower amounts of adsorbed species.Also,Ru addition seems to diminish the degree of degradation of the catalyst.Based on characterization and in agreement with essays carried out in a PEM cell at mild conditions(80℃ and 1 atm),PtRu/C 2:1 anode provided the best electrocatalytic results in terms of current density(740 mA cm^(-2)),hydrogen production and selectivity toward acetic acid(up to 15%apart from acetaldehyde and ethyl acetate)while requiring the lowest energy consumption. 展开更多
关键词 Ethanol electro-reforming PEM cell Pt:Ru anodic ratio Hydrogen production value-added liquid product distribution
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Operational mechanism of comprehensive benefit evaluation of existing building energy efficient renovation project based on value-added life
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作者 GUO Han-ding WEI Yong-cheng +1 位作者 CUI Si-wen ZHANG Yin-xian 《Ecological Economy》 2019年第4期280-288,共9页
The comprehensive benefit evaluation of the existing building energy efficient renovation project cannot be separated from the scientific and effective evaluation mechanism.Based on the value-added life perspective,th... The comprehensive benefit evaluation of the existing building energy efficient renovation project cannot be separated from the scientific and effective evaluation mechanism.Based on the value-added life perspective,this paper analyzes the implementation subject,standard,system and principle of the comprehensive benefit evaluation of the existing building energy efficient renovation project.It plans the process of comprehensive benefit evaluation,and builds a scientific and reasonable operation platform of evaluation system,with a view to promoting the effective implementation of the comprehensive benefit evaluation of existing building energy-saving retrofits. 展开更多
关键词 energy efficient RENOVATION existing building value-added LIFE COMPREHENSIVE BENEFIT evaluation OPEratioNAL mechanism
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基于改进Ratio统计量的重尾AR(p)时间序列均值变点检验
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作者 张思 刘叶 金浩 《统计与决策》 CSSCI 北大核心 2024年第2期52-57,共6页
文章提出两个改进的Ratio统计量来研究重尾AR(p)时间序列均值变点检验问题,在原假设下推导了统计量的渐近分布,且在备择假设下证明了其一致性。由于重尾指数未知且难以估计,因此结合Wild Bootstrap重抽样方法来确定渐近分布的临界值;在... 文章提出两个改进的Ratio统计量来研究重尾AR(p)时间序列均值变点检验问题,在原假设下推导了统计量的渐近分布,且在备择假设下证明了其一致性。由于重尾指数未知且难以估计,因此结合Wild Bootstrap重抽样方法来确定渐近分布的临界值;在均值变点存在的情形下,给出了变点位置的一致估计量。数值模拟结果表明:统计量的临界值均不受重尾指数和自回归系数的影响,其经验水平和经验势均取得满意的效果;尤其在原假设下,积分型Ratio统计量的经验水平表现出更好的稳健性,而在备择假设下,最值型Ratio统计量则具备更好的显著性。最后,基于一组股票数据,从实际应用角度进一步阐明所提方法的有效性和可行性。 展开更多
关键词 重尾序列 ratio统计量 均值变点 Wild Bootstrap
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Artificial photosynthesis for high-value-added chemicals:Old material,new opportunity 被引量:7
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作者 Sungsoon Kim Kwang Hee Kim +2 位作者 Cheoulwoo Oh Kan Zhang Jong Hyeok Park 《Carbon Energy》 SCIE CAS 2022年第1期21-44,共24页
Solar energy utilization has drawn attention due to ever-increasing environmental and energy issues.Photoelectrochemical(PEC)and photocatalytic(PC)water splitting for hydrogen production,which is the most popular and ... Solar energy utilization has drawn attention due to ever-increasing environmental and energy issues.Photoelectrochemical(PEC)and photocatalytic(PC)water splitting for hydrogen production,which is the most popular and well-established solar-to-chemical conversion process,has been studied thoroughly to date but is now facing limitations related to low conversion efficiency.To resolve this issue,research in PEC cells or photocatalysts has recently aimed to produce alternative value-added chemicals by modifying their redox reactions,which potentially enables high economic reward to compensate for the low efficiency.Here,various kinds of redox reactions that decouple classic water splitting reactions to produce value-added chemicals via PEC and PC processes are introduced.Successful coupling of CO_(2) reduction,O_(2) reduction and organic synthesis with either water oxidation or water reduction is comprehensively discussed from the perspective of basic fundamental and product selectivity in terms of the band structure of materials,cocatalyst design,and thermodynamics and kinetics of the reactions.Throughout the review,future challenges and opportunities are suggested with respect to the redesigned artificial synthesis,which might be an alternative development for the commercialization of PEC or PC value-added chemical production technologies in the near future. 展开更多
关键词 artificial photosynthesis PHOTOCATALYSTS photoelectrochemical cells redox reactions value-added chemical production
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Food processing wastewater purification by microalgae cultivation associated with high value-added compounds production——A review 被引量:3
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作者 Shuhong Li Shuang Zhao +4 位作者 Siliang Yan Yiting Qiu Chunfeng Song Yang Li Yutaka Kitamura 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第12期2845-2856,共12页
Microalgae have been considered as an efficient microorganism for wastewater treatment with simultaneously bioenergy and high value-added compounds production.However,the high energy cost associated with complicated b... Microalgae have been considered as an efficient microorganism for wastewater treatment with simultaneously bioenergy and high value-added compounds production.However,the high energy cost associated with complicated biorefinery(e.g.microalgae cultivation,harvesting,drying,extraction,conversion,and purification)is a critical challenge that inhibits its large-scale application.Among different nutrition(e.g.carbon,nitrogen and phosphorous)sources,food processing wastewater is a relative safe and suitable one for microalgae cultivation due to its high organic content and low toxicity.In this review,the characteristic of different food wastewater is summarized and compared.The potential routes of value-added products(i.e.biofuel,pigment,polysaccharide,and amino acid)production along with wastewater purification are introduced.The existing challenges(e.g.biorefinery cost,efficiency and mechanism)of microalgal-based wastewater treatment are also discussed.The prospective of microalgae-based food processing wastewater treatment strategies(such as microalgae-bacteria consortium,poly-generation of bioenergy and value-added products)is forecasted.It can be observed that food wastewater treatment by microalgae could be a promising strategy to commercially realize waste source reduce,conversion and reutilization. 展开更多
关键词 Food wastewater MICROALGAE value-added PRODUCE BIOFUEL POLYSACCHARIDE Protein
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Brief analysis on value-added tax transformation and its influence on enterprises
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作者 HUANG Wei-mo 《Chinese Business Review》 2009年第2期55-58,共4页
From Jan. 1st, 2009, the value-added tax transformation will be performed in all industries around the country. Based on value-added tax types and retrospection of reform practices, this article analyzes the backgroun... From Jan. 1st, 2009, the value-added tax transformation will be performed in all industries around the country. Based on value-added tax types and retrospection of reform practices, this article analyzes the background of the national value-added tax transformation and points out the influence of full implementation of the value-added tax transformation on various enterprises. 展开更多
关键词 value-added tax value-added tax transformation production value-added tax consumption value-added tax
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Evolution trends and structural decomposition of China's green value-added over 40 years of reform and opening-up
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作者 Jin Fan Wei Wan +1 位作者 Xiaohui Yuan Fatemeh Ranaei 《Chinese Journal of Population,Resources and Environment》 2020年第2期69-78,共10页
China's 40-year history of reform and opening-up includes rapid economic development as well as pollution and environmental governance.Using a four-stage division,this study explores the evolution trend and struct... China's 40-year history of reform and opening-up includes rapid economic development as well as pollution and environmental governance.Using a four-stage division,this study explores the evolution trend and structural decomposition of China's green value-added by constructing a non-competitive input-output table for environmental pollution from 1978 to 2017.The results indicate that pollution production coefficients increased continuously,and the green value-added index decreased.Additionally,the structural decomposition showed that investment and export were critical for economic growth during the period,though they were accompanied by serious pollution problems.The pollution generated by the raw material(represented by coal mining)and processing industries(represented by the textiles)were not controlled effectively.Pollution treatment for these industries should be strengthened in the future.The study has implications for government officials,policy makers,and academics.First,China should make green development a core concept for economic development,increase environmental pollution governance,develop a“green GDP,”incorporate the external costs of environmental pollution into the national economic accounting system.Second,it must change the investment and export structure as well as the traditional economic development pattern that exacerbates pollution.Specifically,the country should develop industries with low pollution and promote the export of industries producing high value-added products and increase green GDP per capita.Third,it should closely monitor the development of highly polluting industries.Upgrading technology to reduce pollution and strengthening pollution treatment will reduce the number of polluting industries and improve environmental governance efficiency. 展开更多
关键词 Green value-added Non-competitive input-output table Factor decomposition Environmental governance
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Reactive ball-milling synthesis of Co-Fe bimetallic catalyst for efficient hydrogenation of carbon dioxide to value-added hydrocarbons
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作者 Haipeng Chen Chenwei Wang +5 位作者 Mengyang Zheng Chenlei Liu Wenqiang Li Qingfeng Yang Shixue Zhou Xun Feng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期210-218,共9页
Catalytic hydrogenation of CO_(2) using renewable hydrogen not only reduces greenhouse gas emissions,but also provides industrial chemicals.Herein,a Co-Fe bimetallic catalyst was developed by a facile reactive ball-mi... Catalytic hydrogenation of CO_(2) using renewable hydrogen not only reduces greenhouse gas emissions,but also provides industrial chemicals.Herein,a Co-Fe bimetallic catalyst was developed by a facile reactive ball-milling method for highly active and selective hydrogenation of CO_(2) to value-added hydrocarbons.When reacted at 320℃,1.0 MPa and 9600 mL h^(-1) g_(cat)^(-1),the selectivity to light olefin(C_(2)^(=)-C_(4)^(=)) and C_(5)+ species achieves 57.3% and 22.3%,respectively,at a CO_(2) co nversion of 31.4%,which is superior to previous Fe-based catalysts.The CO_(2) activation can be promoted by the CoFe phase formed by reactive ball milling of the Fe-Co_(3)O_(4) mixture,and the in-situ Co_(2)C and Fe_(5)C_(2) formed during hydrogenation are beneficial for the C-C coupling reaction.The initial C-C coupling is related to the combination of CO species with the surface carbon of Fe/Co carbides,and the sustained C-C coupling is maintained by self-recovery of defective carbides.This new strategy contributes to the development of efficient catalysts for the hydrogenation of CO_(2) to value-added hydrocarbons. 展开更多
关键词 Reactive ball milling Co-Fe bimetallic catalyst Carbon dioxide value-added hydrocarbon C–C coupling reaction
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PoC: An IMS-based Wireless Value-added Service
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作者 Liu Xiaowen,Zhang Lijun (Department of Communication Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210003, China) 《ZTE Communications》 2005年第4期21-24,共4页
This article introduces the Push-to-talk over Cellular( PoC) service, a new mobile value-added service based on the IP Multimedia Subsystem (IMS). Its implementation scheme is discussed and its Session Initiation Prot... This article introduces the Push-to-talk over Cellular( PoC) service, a new mobile value-added service based on the IP Multimedia Subsystem (IMS). Its implementation scheme is discussed and its Session Initiation Protocol (SIP) signaling exchange flow is described. Target user groups are predicted based on the analysis of the strengths and weaknesses of the PoC service. The article purports that the PoC system could undoubtedly be used as a platform for new services such as multimedia messaging, instant messaging, presence, and picture receiving and sending. Just like the short message service, the PoC service will help the terminal vendors, equipment vendors, content providers and operators setup a win-for-all industrial value chain. 展开更多
关键词 IMS FIGURE POC An IMS-based Wireless value-added Service GPP Server UMTS
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Export Value-Added of China’s Manufacturing Sector:Estimation and Mechanism Analysis
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作者 樊秀峰 程文先 《China Economist》 2015年第6期66-77,共12页
Estimation of domestic and overseas value-added of manufacturing sector is an important and difficult subject for the science-based evaluation of a country's trade interests under global value chain. Traditional HIY ... Estimation of domestic and overseas value-added of manufacturing sector is an important and difficult subject for the science-based evaluation of a country's trade interests under global value chain. Traditional HIY approach overestimates the domestic value- added of export. Although Koopman's method made certain improvements, it cannot utilize traditional I/O matrix and direct input coefficient matrix under the condition of incomplete information. By creating GAMS model, this paper addresses the above-mentioned problems and employs an improved model for the estimation of variations in domestic and overseas value-added of Chinese exports between 2002 and 2012. Our results indicate that by neglecting the export of processing trade, HIY approach overestimates the domestic value- added ratio of Chinese exports. As more imported intermediate inputs have been used in the export of processing trade, the estimation result of this paper have corrected deviations in the forecast of overseas value-added ratio and its tendencies based on HIY method Further analysis of specific factors of domestic value-added of export led to the discovery that the domestic value-added of export of processing trade and mixed trade is highly vulnerable to the impact of international capital inflow. It can be seen that the improved method for the estimation of value-added has indeed corrected the deviations in the estimation of China's value-added. In conclusion, China should accelerate the development of export of non- processing trade and trade in high-end services, and balance the relationship of export between local firms and foreign-funded firms, with a view to improving trade dependence and increasing the trade status of Chinese manufaeturing firms in global value chain. 展开更多
关键词 global value chain domestic value-added processing trade estimationapproach
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International Competitiveness of China’s Manufacturing Sectors:Estimation Based on Trade in Value-added
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作者 戴翔 《China Economist》 2015年第6期110-122,共13页
Based on trade in value-added, this paper has estimated the revealed comparative advantage (RCA) of China's various manufacturing sectors between 1995 and 2011 and compared with the RCA indexes measured using conve... Based on trade in value-added, this paper has estimated the revealed comparative advantage (RCA) of China's various manufacturing sectors between 1995 and 2011 and compared with the RCA indexes measured using conventional aggregate accounting approach. Results indicate that: (1) the RCA index measured using conventional aggregate accounting approach has underestimated China's comparative advantage of labor-intensive sectors but overestimated China's comparative advantage in capital, knowledge and technology-intensive manufacturing sectors, giving rise to a serious misjudgment. (2) The RCA measured using value-added approach shows that in the industry chain layout of global manufacturing sectors, China's comparative advantage is still concentrated in labor-intensive manufacturing sectors but has signs of weakening; in capital, knowledge and technology-intensive sectors, China is yet to develop any significant comparative advantage; there are signs that China is developing comparative advantage in capital-intensive sectors yet China's comparative disadvantage in knowledge and technology-intensive sectors has no significant tendency to improve. This result not only helps correct the misjudgment of China's competitiveness in manufacturing sectors based on conventional aggregate accounting approach but offers important policy implications for setting strategic directions and policies for China's manufacturing transition and upgrade. 展开更多
关键词 trade in value-added international competitiveness revealed comparativeadvantage (RCA)
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Distribution of Value-added Income of Collective Construction Land Entering the Market Based on the Subject Input Contribution and TOPSIS
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作者 Chenguang YUAN Lingchao WANG 《Asian Agricultural Research》 2021年第12期19-22,共4页
In order to promote the revitalization and development of rural areas and protect the property rights of farmers,it is necessary to explore the reasonable distribution ratio of land value-added income in collective op... In order to promote the revitalization and development of rural areas and protect the property rights of farmers,it is necessary to explore the reasonable distribution ratio of land value-added income in collective operating construction land.Under the existing land value-added income distribution model,the land value-added income obtained by the government is much greater than that of village collectives,and it is difficult for village collectives and farmers to enjoy greater benefits.This distribution model is not conducive to protecting the property rights of farmers.The results show that there was a positive correlation between land value-added income and land level,that is,the higher the land level was,the higher the value-added income and its ratio to the market transaction price were.According to calculation,the reasonable distribution ratio of the value-added income of collective operating construction land entering the market among the government,village collectives and farmers was 28.6%,51.1%,and 20.3%respectively.The actual land value-added income obtained by farmers was greatly improved compared with the current situation.In actual operation,this distribution mode has universal applicability.The reform of entering the market in the future also needs to raise the standards for entering the market,explore diversified interest protection channels,and strengthen the construction of rural collective management system. 展开更多
关键词 Collective operating construction land Land value-added income Subject input contribution TOPSIS
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Yields,growth and water use under chemical topping in relations to row configuration and plant density in drip-irrigated cotton 被引量:1
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作者 Wang Xuejiao Hu Yanping +10 位作者 Ji Chunrong Chen Yongfan Sun Shuai Zhang Zeshan Zhang Yutong Wang Sen Yang Mingfeng Ji Fen Guo Yanyun Li Jie Zhang Lizhen 《Journal of Cotton Research》 CAS 2024年第2期123-136,共14页
Background Water deficit is an important problem in agricultural production in arid regions.With the advent of wholly mechanized technology for cotton planting in Xinjiang,it is important to determine which planting m... Background Water deficit is an important problem in agricultural production in arid regions.With the advent of wholly mechanized technology for cotton planting in Xinjiang,it is important to determine which planting mode could achieve high yield,fiber quality and water use efficiency(WUE).This study aimed to explore if chemical topping affected cotton yield,quality and water use in relation to row configuration and plant densities.Results Experiments were carried out in Xinjiang China,in 2020 and 2021 with two topping method,manual topping and chemical topping,two plant densities,low and high,and two row configurations,i.e.,76 cm equal rows and 10+66 cm narrow-wide rows,which were commonly applied in matching harvest machine.Chemical topping increased seed cotton yield,but did not affect cotton fiber quality comparing to traditional manual topping.Under equal row spacing,the WUE in higher density was 62.4%higher than in the lower one.However,under narrow-wide row spacing,the WUE in lower density was 53.3%higher than in higher one(farmers’practice).For machine-harvest cotton in Xinjiang,the optimal row configuration and plant density for chemical topping was narrow-wide rows with 15 plants m-2 or equal rows with 18 plants m-2.Conclusion The plant density recommended in narrow-wide rows was less than farmers’practice and the density in equal rows was moderate with local practice.Our results provide new knowledge on optimizing agronomic managements of machine-harvested cotton for both high yield and water efficient. 展开更多
关键词 Yield components Fiber quality TRANSPIratioN Water use efficiency Heat ratio method(HRM)
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Combining lymph node ratio to develop prognostic models for postoperative gastric neuroendocrine neoplasm patients 被引量:1
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作者 Wen Liu Hong-Yu Wu +4 位作者 Jia-Xi Lin Shu-Ting Qu Yi-Jie Gu Jin-Zhou Zhu Chun-Fang Xu 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第8期3507-3520,共14页
BACKGROUND Lymph node ratio(LNR)was demonstrated to play a crucial role in the prognosis of many tumors.However,research concerning the prognostic value of LNR in postoperative gastric neuroendocrine neoplasm(NEN)pati... BACKGROUND Lymph node ratio(LNR)was demonstrated to play a crucial role in the prognosis of many tumors.However,research concerning the prognostic value of LNR in postoperative gastric neuroendocrine neoplasm(NEN)patients was limited.AIM To explore the prognostic value of LNR in postoperative gastric NEN patients and to combine LNR to develop prognostic models.METHODS A total of 286 patients from the Surveillance,Epidemiology,and End Results database were divided into the training set and validation set at a ratio of 8:2.92 patients from the First Affiliated Hospital of Soochow University in China were designated as a test set.Cox regression analysis was used to explore the relationship between LNR and disease-specific survival(DSS)of gastric NEN patients.Random survival forest(RSF)algorithm and Cox proportional hazards(CoxPH)analysis were applied to develop models to predict DSS respectively,and compared with the 8th edition American Joint Committee on Cancer(AJCC)tumornode-metastasis(TNM)staging.RESULTS Multivariate analyses indicated that LNR was an independent prognostic factor for postoperative gastric NEN patients and a higher LNR was accompanied by a higher risk of death.The RSF model exhibited the best performance in predicting DSS,with the C-index in the test set being 0.769[95%confidence interval(CI):0.691-0.846]outperforming the CoxPH model(0.744,95%CI:0.665-0.822)and the 8th edition AJCC TNM staging(0.723,95%CI:0.613-0.833).The calibration curves and decision curve analysis(DCA)demonstrated the RSF model had good calibration and clinical benefits.Furthermore,the RSF model could perform risk stratification and individual prognosis prediction effectively.CONCLUSION A higher LNR indicated a lower DSS in postoperative gastric NEN patients.The RSF model outperformed the CoxPH model and the 8th edition AJCC TNM staging in the test set,showing potential in clinical practice. 展开更多
关键词 Gastric neuroendocrine neoplasm Lymph node ratio Disease-specific survival Random survival forest Predictive model
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Value-Added Tax (VAT) on Selected Financial Transactions
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作者 Yvona Legierska 《Journal of Modern Accounting and Auditing》 2014年第8期846-852,共7页
This paper deals with the approach to imposing value-added tax (VAT) on financial transactions. The VAT is a highly harmonized consumption tax within the European Union (EU). VAT operational rules have been set do... This paper deals with the approach to imposing value-added tax (VAT) on financial transactions. The VAT is a highly harmonized consumption tax within the European Union (EU). VAT operational rules have been set down by the relevant directive of the Council of the EU. Under the directive, it is possible to select either exemption or taxation of financial transactions. Only the first option is permitted in the Czech Republic. Pros and cons of both models are described, in particular, the problems with determining the difference between financial transactions and other similar performance that must always be subject to tax. Potential lower VAT revenue or tax base assessment, as appropriate, seems to be crucial in the case of the taxation of financial transactions. 展开更多
关键词 value-added tax (VAT) financial services financial transactions reverse charge option to tax cost-sharing agreement
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"Add-ons" to the Value-Added of ELTs
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作者 Srinivasa Rao Idapalapati 《Sino-US English Teaching》 2014年第1期1-12,共12页
Teacher evaluations intend to cultivate quality among teachers. However, since they are traditionally dependent on observers and their reports that are likely biased, the procedures probably effectuate discords among ... Teacher evaluations intend to cultivate quality among teachers. However, since they are traditionally dependent on observers and their reports that are likely biased, the procedures probably effectuate discords among the calling-teaching professionals. An evaluation procedure that can ascertain fairness in the decisions about teacher retentions, terminations, promotions, and sanctions can capture the accordance of all teachers and teacher facilitators. This paper identifies the possibility of such an evaluation system that is built upon the existing value-added methods. Drawing upon the observations and recommendations by Chetty, Friedman, and Rockoff (2012) on value-added methods of evaluation, and considering the uniqueness of ELTs (English Language Teachers) as it was observed by Borg (2006) and Lee (2010), this paper describes the application of the value-added evaluation method, in gauging the quality of ELTs. The paper further explicates the vantages and conformities embodied in the procedure that could boost up the morale of ELTs as independent professionals of a creative art, and help them perform to their fullest potential 展开更多
关键词 teachers' accountability learning outcomes VA value-added self-assertion of performances measuring PD (Professional Development)
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A gated recurrent unit model to predict Poisson’s ratio using deep learning 被引量:1
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作者 Fahd Saeed Alakbari Mysara Eissa Mohyaldinn +4 位作者 Mohammed Abdalla Ayoub Ibnelwaleed A.Hussein Ali Samer Muhsan Syahrir Ridha Abdullah Abduljabbar Salih 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期123-135,共13页
Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to spe... Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to specific data ranges with an average absolute percentage relative error(AAPRE)of more than 10%.The published gated recurrent unit(GRU)models do not consider trend analysis to show physical behaviors.In this study,we aim to develop a GRU model using trend analysis and three inputs for predicting n s based on a broad range of data,n s(value of 0.1627-0.4492),bulk formation density(RHOB)(0.315-2.994 g/mL),compressional time(DTc)(44.43-186.9 μs/ft),and shear time(DTs)(72.9-341.2μ s/ft).The GRU model was evaluated using different approaches,including statistical error an-alyses.The GRU model showed the proper trends,and the model data ranges were wider than previous ones.The GRU model has the largest correlation coefficient(R)of 0.967 and the lowest AAPRE,average percent relative error(APRE),root mean square error(RMSE),and standard deviation(SD)of 3.228%,1.054%,4.389,and 0.013,respectively,compared to other models.The GRU model has a high accuracy for the different datasets:training,validation,testing,and the whole datasets with R and AAPRE values were 0.981 and 2.601%,0.966 and 3.274%,0.967 and 3.228%,and 0.977 and 2.861%,respectively.The group error analyses of all inputs show that the GRU model has less than 5% AAPRE for all input ranges,which is superior to other models that have different AAPRE values of more than 10% at various ranges of inputs. 展开更多
关键词 Static Poisson’s ratio Deep learning Gated recurrent unit(GRU) Sand control Trend analysis Geomechanical properties
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Serum cystatin C,monocyte/high-density lipoprotein-C ratio,and uric acid for the diagnosis of coronary heart disease and heart failure 被引量:1
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作者 Ming Li Da-Hao Yuan +2 位作者 Zhi Yang Teng-Xiang Luw Xiao-Biao Zou 《World Journal of Clinical Cases》 SCIE 2024年第18期3461-3467,共7页
BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.Howeve... BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.However,conventional diagnostic methods such as electrocardiography,echocardiography,and cardiac biomarkers have certain limitations,such as low sensitivity,specificity,availability,and cost-effectiveness.Therefore,there is a need for simple,noninvasive,and reliable biomarkers to diagnose CHD and HF.AIM To investigate serum cystatin C(Cys-C),monocyte/high-density lipoprotein cholesterol ratio(MHR),and uric acid(UA)diagnostic values for CHD and HF.METHODS We enrolled 80 patients with suspected CHD or HF who were admitted to our hospital between July 2022 and July 2023.The patients were divided into CHD(n=20),HF(n=20),CHD+HF(n=20),and control groups(n=20).The serum levels of Cys-C,MHR,and UA were measured using immunonephelometry and an enzymatic method,respectively,and the diagnostic values for CHD and HF were evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Serum levels of Cys-C,MHR,and UA were significantly higher in the CHD,HF,and CHD+HF groups than those in the control group.The serum levels of Cys-C,MHR,and UA were significantly higher in the CHD+HF group than those in the CHD or HF group.The ROC curve analysis showed that serum Cys-C,MHR,and UA had good diagnostic performance for CHD and HF,with areas under the curve ranging from 0.78 to 0.93.The optimal cutoff values of serum Cys-C,MHR,and UA for diagnosing CHD,HF,and CHD+HF were 1.2 mg/L,0.9×10^(9),and 389μmol/L;1.4 mg/L,1.0×10^(9),and 449μmol/L;and 1.6 mg/L,1.1×10^(9),and 508μmol/L,respectively.CONCLUSION Serum Cys-C,MHR,and UA are useful biomarkers for diagnosing CHD and HF,and CHD+HF.These can provide information for decision-making and risk stratification in patients with CHD and HF. 展开更多
关键词 Serum cystatin C Monocyte/high-density lipoprotein-C ratio Uric acid Coronary heart disease Heart failure Risk stratification
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