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China's Imp.& Exp.of New and High-tech Products
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《中国经贸》 2002年第10期22-23,共2页
Import of New and High-tech Products Increases Rapidly The proportion of new and high-tech products in the total import continues to increase.Ever since 1991,the proportion of new and high-tech products in the total i... Import of New and High-tech Products Increases Rapidly The proportion of new and high-tech products in the total import continues to increase.Ever since 1991,the proportion of new and high-tech products in the total import has experienced a continuous growth.It took up only 14.8% of the total import in 1991.The figure reached 20.8% in 1998,and further rose to that of 26.3% in 2001.From January to June this year,the import of new and hightech products totaled 34.540 billion USD,up 18.1% over the same per... 展开更多
关键词 PR HIGH Exp.of New and high-tech products China’s Imp
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Quality of High-Tech Product Marketing A Comparative Study Between Chinese and European Telecommunication Companies in Saudi Arabian Market
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作者 Abdullah Saleh Alshetwi 《Economics World》 2014年第3期147-151,共5页
This paper specifies substantial characteristics in high-tech industry which is playing an increasingly dominant role in men's lives with the rapid development of high-tech industry, among which the telecommunication... This paper specifies substantial characteristics in high-tech industry which is playing an increasingly dominant role in men's lives with the rapid development of high-tech industry, among which the telecommunication industry is the best example. From a macro perspective, competition has been fierce in high-tech and telecom over the past years, especially in increasingly saturated markets such as North America and Europe. In order to sustain and thrive in this market, companies have to apply various applicable strategies. The dominance of enterprises from developed nations is not a rare phenomenon. How China as a late-comer can succeed in the high-tech field is a serious issue that requires consideration. China's Huawei, a relatively new enterprise that has become a leader in telecom industry, boasts a perfect example in this case. This paper attempts to investigate how Huawei made its way into the telecom sector by comparing with Ericsson, a giant telecom enterprise in European market. More specifically, the paper aims to explore the most significant factors in developing a suitable marketing strategy for telecom companies in Saudi Arabia. The results of the study show that given the nature of telecom industry, innovation and customization play a crucial role in venturing in foreign nations. It can also be concluded that an overall analysis of various factors is quite essential when entering middle-eastern markets such as Saudi Arabia. This also gives China a revelation that being a late-comer is never an excuse to expand its telecom sector, instead, as long as due attention is given to enterprises' marketing strategies and competitiveness. Conclusions have been made about the nature, characteristics, the Saudi Arabia markets, and goals and objectives telecommunication in Saudi Arabia. Methodology has been used for stating and structuring the empirical data. 展开更多
关键词 marketing strategies innovation high-tech industry COMPETITIVENESS TELECOMMUNICATION HUAWEI ERICSSON
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Crosstalk between degradation and bioenergetics: how autophagy and endolysosomal processes regulate energy production
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作者 Angelid Pabon Jagannatham Naidu Bhupana Ching-On Wong 《Neural Regeneration Research》 SCIE CAS 2025年第3期671-681,共11页
Cells undergo metabolic reprogramming to adapt to changes in nutrient availability, cellular activity, and transitions in cell states. The balance between glycolysis and mitochondrial respiration is crucial for energy... Cells undergo metabolic reprogramming to adapt to changes in nutrient availability, cellular activity, and transitions in cell states. The balance between glycolysis and mitochondrial respiration is crucial for energy production, and metabolic reprogramming stipulates a shift in such balance to optimize both bioenergetic efficiency and anabolic requirements. Failure in switching bioenergetic dependence can lead to maladaptation and pathogenesis. While cellular degradation is known to recycle precursor molecules for anabolism, its potential role in regulating energy production remains less explored. The bioenergetic switch between glycolysis and mitochondrial respiration involves transcription factors and organelle homeostasis, which are both regulated by the cellular degradation pathways. A growing body of studies has demonstrated that both stem cells and differentiated cells exhibit bioenergetic switch upon perturbations of autophagic activity or endolysosomal processes. Here, we highlighted the current understanding of the interplay between degradation processes, specifically autophagy and endolysosomes, transcription factors, endolysosomal signaling, and mitochondrial homeostasis in shaping cellular bioenergetics. This review aims to summarize the relationship between degradation processes and bioenergetics, providing a foundation for future research to unveil deeper mechanistic insights into bioenergetic regulation. 展开更多
关键词 AUTOPHAGY BIOENERGETICS endolysosome energy production GLYCOLYSIS metabolic reprogramming MITOCHONDRIA
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Coagulation indices and fibrinogen degradation products as predictive biomarkers for tumor-node-metastasis staging and metastasis in gastric cancer
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作者 Yi-Qing Shen Qiu-Wan Wei +2 位作者 Yi-Ren Tian Yun-Zhi Ling Min Zhang 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期110-120,共11页
BACKGROUND Gastric cancer(GC)is a prevalent malignancy with a substantial health burden and high mortality rate,despite advances in prevention,early detection,and treatment.Compared with the global average,Asia,notabl... BACKGROUND Gastric cancer(GC)is a prevalent malignancy with a substantial health burden and high mortality rate,despite advances in prevention,early detection,and treatment.Compared with the global average,Asia,notably China,reports disproportionately high GC incidences.The disease often progresses asymptoma-tically in the early stages,leading to delayed diagnosis and compromised out-comes.Thus,it is crucial to identify early diagnostic biomarkers and enhance treatment strategies to improve patient outcomes and reduce mortality.METHODS Retrospectively analyzed the clinical data of 148 patients with GC treated at the Civil Aviation Shanghai Hospital between December 2022 and December 2023.The associations of coagulation indices-partial thromboplastin time(APTT),prothrombin time(PT),thrombin time(TT),fibrinogen,fibrinogen degradation products(FDP),fasting blood glucose,and D-dimer(D-D)with TNM stage and distant metastasis were examined.RESULTS Prolongation of APTT,PT,and TT was significantly correlated with the GC TNM stage.Hence,abnormal coagulation system activation was closely related to disease progression.Elevated FDP and D-D were significantly associated with distant metastasis in GC(P<0.05),suggesting that increased fibrinolytic activity contributes to increased metastatic risk.CONCLUSION Our Results reveal coagulation indices,FDPs as GC biomarkers,reflecting abnormal coagulation/fibrinolysis,aiding disease progression,metastasis prediction,and helping clinicians assess thrombotic risk for early intervention and personalized treatment plans. 展开更多
关键词 Coagulation indexes Fibrinogen degradation products Gastric cancer Tumor-node-metastasis staging Distant metastasis
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Scalable Ir‑Doped NiFe_(2)O_(4)/TiO_(2)Heterojunction Anode for Decentralized Saline Wastewater Treatment and H_(2)Production
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作者 Sukhwa Hong Jiseon Kim +3 位作者 Jaebeom Park Sunmi Im Michael R.Hoffmann Kangwoo Cho 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期1-18,共18页
Wastewater electrolysis cells(WECs)for decentralized wastewater treatment/reuse coupled with H_(2)production can reduce the carbon footprint associated with transportation of water,waste,and energy carrier.This study ... Wastewater electrolysis cells(WECs)for decentralized wastewater treatment/reuse coupled with H_(2)production can reduce the carbon footprint associated with transportation of water,waste,and energy carrier.This study reports Ir-doped NiFe_(2)O_(4)(NFI,~5 at%Ir)spinel layer with TiO_(2)overlayer(NFI/TiO_(2)),as a scalable heterojunction anode for direct electrolysis of wastewater with circumneutral pH in a single-compartment cell.In dilute(0.1 M)NaCl solutions,the NFI/TiO_(2)marks superior activity and selectivity for chlorine evolution reaction,outperforming the benchmark IrO_(2).Robust operation in near-neutral pH was confirmed.Electroanalyses including operando X-ray absorption spectroscopy unveiled crucial roles of TiO_(2) which serves both as the primary site for Cl−chemisorption and a protective layer for NFI as an ohmic contact.Galvanostatic electrolysis of NH4+-laden synthetic wastewater demonstrated that NFI/TiO_(2)not only achieves quasi-stoichiometric NH_(4)^(+)-to-N_(2)conversion,but also enhances H_(2)generation efficiency with minimal competing reactions such as reduction of dissolved oxygen and reactive chlorine.The scaled-up WEC with NFI/TiO_(2)was demonstrated for electrolysis of toilet wastewater. 展开更多
关键词 Wastewater electrolysis cell Ir-doped NiFe_(2)O_(4) Reactive chlorine species Decentralized H_(2)production On-site wastewater treatment
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A Decision Support System for Identification and Evaluation of High-tech Products 被引量:1
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作者 GAO Chang-yuan, LIANG Jing-guo, CAO Xiu-ying School of Economics & Management, Harbin Engineering University, Harbin 150080, China 《Systems Science and Systems Engineering》 CSCD 2002年第1期37-42,共6页
According to high-tech product features and decision support system theory, a decision support system (DSS) for identification and evaluation of high-tech products has been designed which consists of the user interfac... According to high-tech product features and decision support system theory, a decision support system (DSS) for identification and evaluation of high-tech products has been designed which consists of the user interface subsystem, the data management subsystem, the model management subsystem and the knowledge management subsystem. This paper describes the function and the framework of the system. 展开更多
关键词 high-tech product EVALUATION DSS
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National Concentration of High-tech Products:The Second Great Diverqence?
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作者 Bing Lu Jiandong Ju Xinding Yu 《China & World Economy》 2023年第1期88-118,共31页
Based on the product-country level trade data from 2004 to 2017,as well as the High-Tech Products Catalog from the US Census Bureau,this paper examines empirically the current phenomenon of"national concentration... Based on the product-country level trade data from 2004 to 2017,as well as the High-Tech Products Catalog from the US Census Bureau,this paper examines empirically the current phenomenon of"national concentration"in high-tech exports.The results show that the phenomenon of"national concentration"not only exists but also tends to be self-reinforcing.Compared with other products,the exports of high-tech products tend to be concentrated in certain countries,and this concentration trends were further strengthened after the global financial crisis of2008-2009.The national concentration of R&D activities may be one of the important causes of the national concentration of high-tech products.This pattern remains robust when we further use the value-added export data and different definitions of high-tech products.We argue that the phenomenon of"national concentration"of high-tech exports may herald the arrival of the"Second Great Divergence"-the divergence between innovative and manufacturing activities-in the global economy. 展开更多
关键词 high-tech products national concentration R&D second great divergence
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The Impact of the Establishment of National High-tech Zones on Total Factor Productivity of Chinese Enterprises
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作者 Wang Mingyi Liu Xiaoyu 《China Economist》 2023年第3期68-93,共26页
The National High-tech Zone(NHTZs)is an important strategic platform for cultivating high-tech industries and realizing high-quality economic development in China.Based on the combined data from 2006 to 2014 of the in... The National High-tech Zone(NHTZs)is an important strategic platform for cultivating high-tech industries and realizing high-quality economic development in China.Based on the combined data from 2006 to 2014 of the industrial enterprise database,the customs database,and the China Development Zones Audit and Announcement Catalogue(abbreviated asthe Catalogue),this paper systematically investigates the influence of the construction of NHTZs on enterprise’s total factor productivity(TFP).Results show that NHTZs have a positive impact on the TFP of enterprises in the zone,and this conclusion is still valid after considering endogeneity problems.Furthermore,the above productivity effects of NHTZs are heterogeneous in terms of enterprise ownership,external environment and establishment time,and NHTZs have greater stimulation effects on enterprise productivity after comparing with other types of functional zones.An investigation of the specific mechanisms at play shows that NHTZs promote the TFP of enterprises in the zone through the release of preferential policies,strengthening the“technology spillover effects”of imported intermediate goods,enhancing enterprise’s innovation ability and attracting talent.In addition,based on the decomposition of industry productivity,this paper also investigates the impact of NHTZs on changes in industry productivity and finds that NHTZs promote the overall productivity of specific industries mainly by stimulating the productivity improvement of incumbent enterprises and expanding the market share of high-productivity enterprises.Moreover,the preferential policies of NHTZs do not significantly stimulate high-productivity enterprises to enter the zones,nor do they cause low-productivity enterprises to exit.This research is helpful in objectively evaluating the economic effects of the NHTZs in China and in providing a theoretical basis for its further adjustment. 展开更多
关键词 National high-tech Zones(NHTZs) total factor productivity(TFP) DIFFERENCE-IN-DIFFERENCES changes in industry productivity
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Mechanical Modeling and Analysis of Stability Deterioration of Production Well During Marine Hydrate Depressurization Production 被引量:1
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作者 SUN Huan-zhao CHANG Yuan-jiang +4 位作者 SUN Bao-jiang WANG Kang CHEN Guo-ming LI Hao DAI Yong-guo 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期338-351,共14页
Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate decomposition.Therefore,the formations will undergo significant subsidence d... Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate decomposition.Therefore,the formations will undergo significant subsidence during depressurization,which will destroy the original force state of the production well.However,existing research on the stability of oil and gas production wells assumes the formation to be stable,and lacks consideration of the force exerted on the hydrate production well by formation subsidence caused by hydrate decomposition during production.To fill this gap,this paper proposes an analytical method for the dynamic evolution of the stability of hydrate production well considering the effects of hydrate decomposition.Based on the mechanical model of the production well,the basis for stability analysis has been proposed.A multi-field coupling model of the force state of the production well considering the effect of hydrate decomposition and formation subsidence is established,and a solver is developed.The analytical approach is verified by its good agreement with the results from the numerical method.A case study found that the decomposition of hydrate will increase the pulling-down force and reduce the supporting force,which is the main reason for the stability deterioration.The higher the initial hydrate saturation,the larger the reservoir thickness,and the lower the production pressure,the worse the stability or even instability.This work can provide a theoretical reference for the stability maintaining of the production well. 展开更多
关键词 natural gas hydrate production well depressurization production formation deformation stability deterioration
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Classification and technical target of water electrolysis for hydrogen production 被引量:2
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作者 Kahyun Ham Sooan Bae Jaeyoung Lee 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期554-576,I0012,共24页
Continuous efforts are underway to reduce carbon emissions worldwide in response to global climate change.Water electrolysis technology,in conjunction with renewable energy,is considered the most feasible hydrogen pro... Continuous efforts are underway to reduce carbon emissions worldwide in response to global climate change.Water electrolysis technology,in conjunction with renewable energy,is considered the most feasible hydrogen production technology based on the viable possibility of large-scale hydrogen production and the zero-carbon-emission nature of the process.However,for hydrogen produced via water electrolysis systems to be utilized in various fields in practice,the unit cost of hydrogen production must be reduced to$1/kg H_(2).To achieve this unit cost,technical targets for water electrolysis have been suggested regarding components in the system.In this paper,the types of water electrolysis systems and the limitations of water electrolysis system components are explained.We suggest guideline with recent trend for achieving this technical target and insights for the potential utilization of water electrolysis technology. 展开更多
关键词 Water electrolysis Hydrogen production Technical target ELECTROCHEMISTRY
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Upcycling plastic wastes into value-added products via electrocatalysis and photoelectrocatalysis 被引量:2
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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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Single-base editing in IGF2 improves meat production and intramuscular fat deposition in Liang Guang Small Spotted pigs 被引量:4
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作者 Tianqi Duo Xiaohong Liu +11 位作者 Delin Mo Yu Bian Shufang Cai Min Wang Ruiqiang Li Qi Zhu Xian Tong Ziyun Liang Weilun Jiang Shiyi Chen Yaosheng Chen Zuyong He 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期108-126,共19页
Background Chinese indigenous pigs are popular with consumers for their juiciness,flavour and meat quality,but they have lower meat production.Insulin-like growth factor 2(IGF2) is a maternally imprinted growth factor... Background Chinese indigenous pigs are popular with consumers for their juiciness,flavour and meat quality,but they have lower meat production.Insulin-like growth factor 2(IGF2) is a maternally imprinted growth factor that promotes skeletal muscle growth by regulating cell proliferation and differentiation.A single nucleotide polymorphism(SNP) within intron 3 of porcine IGF2 disrupts a binding site for the repressor,zinc finger BED-type containing 6(ZBED6),leading to up-regulation of IGF2 and causing major effects on muscle growth,heart size,and backfat thickness.This favorable mutation is common in Western commercial pig populations,but absent in most Chinese indigenous pig breeds.To improve meat production of Chinese indigenous pigs,we used cytosine base editor 3(CBE3)to introduce IGF2 intron3-C3071T mutation into porcine embryonic fibroblasts(PEFs) isolated from a male Liang Guang Small Spotted pig(LGSS),and single-cell clones harboring the desired mutation were selected for somatic cell nuclear transfer(SCNT) to generate the founder line of IGF2^(T/T) pigs.Results We found the heterozygous progeny IGF2^(C/T) pigs exhibited enhanced expression of IGF2,increased lean meat by 18%-36%,enlarged loin muscle area by 3%-17%,improved intramuscular fat(IMF) content by 18%-39%,marbling score by 0.75-1,meat color score by 0.53-1.25,and reduced backfat thickness by 5%-16%.The enhanced accumulation of intramuscular fat in IGF2^(C/T) pigs was identified to be regulated by the PI3K-AKT/AMPK pathway,which activated SREBP1 to promote adipogenesis.Conclusions We demonstrated the introduction of IGF2-intron3-C3071T in Chinese LGSS can improve both meat production and quality,and first identified the regulation of IMF deposition by IGF2 through SREBP1 via the PI3KAKT/AMPK signaling pathways.Our study provides a further understanding of the biological functions of IGF2and an example for improving porcine economic traits through precise base editing. 展开更多
关键词 CBE3 IGF2 Intramuscular fat Meat production PI3K-AKT/AMPK ZBED6
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Product quality prediction based on RBF optimized by firefly algorithm 被引量:2
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作者 HAN Huihui WANG Jian +1 位作者 CHEN Sen YAN Manting 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期105-117,共13页
With the development of information technology,a large number of product quality data in the entire manufacturing process is accumulated,but it is not explored and used effectively.The traditional product quality pred... With the development of information technology,a large number of product quality data in the entire manufacturing process is accumulated,but it is not explored and used effectively.The traditional product quality prediction models have many disadvantages,such as high complexity and low accuracy.To overcome the above problems,we propose an optimized data equalization method to pre-process dataset and design a simple but effective product quality prediction model:radial basis function model optimized by the firefly algorithm with Levy flight mechanism(RBFFALM).First,the new data equalization method is introduced to pre-process the dataset,which reduces the dimension of the data,removes redundant features,and improves the data distribution.Then the RBFFALFM is used to predict product quality.Comprehensive expe riments conducted on real-world product quality datasets validate that the new model RBFFALFM combining with the new data pre-processing method outperforms other previous me thods on predicting product quality. 展开更多
关键词 product quality prediction data pre-processing radial basis function swarm intelligence optimization algorithm
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Product Innovation in High-tech SMEs:A Case Study of Weili Electronics Co.,Ltd
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作者 何铮 李仕明 《Journal of Electronic Science and Technology of China》 2006年第4期328-332,共5页
Product innovation is an important strategy for high-tech firms, especially for small and medium enterprises. This paper proposes that the technological strategies for SMEs are dynamic and during different phase, ther... Product innovation is an important strategy for high-tech firms, especially for small and medium enterprises. This paper proposes that the technological strategies for SMEs are dynamic and during different phase, there is different innovation strategy which leads to various market performances. In particular, through the case study of Weili Electronics Co., Ltd, we fred that organizational learning abilities play a fundamental role in strategic decision. In addition, the frameworks for the determinants of technological strategies in three stages are established to illustrate the evolutionary processes of product innovation in Weili Electronics Co., Ltd. 展开更多
关键词 product innovation technological strategy high-tech SMEs
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Quantifying the agreement and accuracy characteristics of four satellite-based LULC products for cropland classification in China 被引量:1
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作者 Jie Xue Xianglin Zhang +3 位作者 Songchao Chen Bifeng Hu Nan Wang Zhou Shi 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期283-297,共15页
Various land use and land cover(LULC)products have been produced over the past decade with the development of remote sensing technology.Despite the differences in LULC classification schemes,there is a lack of researc... Various land use and land cover(LULC)products have been produced over the past decade with the development of remote sensing technology.Despite the differences in LULC classification schemes,there is a lack of research on assessing the accuracy of their application to croplands in a unified framework.Thus,this study evaluated the spatial and area accuracies of cropland classification for four commonly used global LULC products(i.e.,MCD12Q1V6,GlobCover2009,FROM-GLC and GlobeLand30)based on the harmonised FAO criterion,and quantified the relationships between four factors(i.e.,slope,elevation,field size and crop system)and cropland classification agreement.The validation results indicated that MCD12Q1 and GlobeLand30 performed well in cropland classification regarding spatial consistency,with overall accuracies of 94.90 and 93.52%,respectively.The FROMGLC showed the worst performance,with an overall accuracy of 83.17%.Overlaying the cropland generated by the four global LULC products,we found the proportions of complete agreement and disagreement were 15.51 and 44.72% for the cropland classification,respectively.High consistency was mainly observed in the Northeast China Plain,the Huang-Huai-Hai Plain and the northern part of the Middle-lower Yangtze Plain,China.In contrast,low consistency was detected primarily on the eastern edge of the northern and semiarid region,the Yunnan-Guizhou Plateau and southern China.Field size was the most important factor for mapping cropland.For area accuracy,compared with China Statistical Yearbook data at the provincial scale,the accuracies of different products in descending order were:GlobeLand30,FROM-GLC,MCD12Q1,and GlobCover2009.The cropland classification schemes mainly caused large area deviations among the four products,and they also resulted in the different ranks of spatial accuracy and area accuracy among the four products.Our results can provide valuable suggestions for selecting cropland products at the national or provincial scale and help cropland mapping and reconstruction,which is essential for food security and crop management,so they can also contribute to achieving the Sustainable Development Goals issued by the United Nations. 展开更多
关键词 global LULC products cropland mapping accuracy evaluation food security China
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Promoting grain production through high-standard farmland construction:Evidence in China 被引量:1
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作者 Shuai Hao Guogang Wang +4 位作者 Yantao Yang Sicheng Zhao Shengnan Huang Liping Liu Huanhuan Zhang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期324-335,共12页
Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capa... Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capacity.Based on panel data from 31 sample provinces,autonomous regions,and municipalities in China from 2005–2017,this study explored the impact of HSFC on grain yield using the difference-in-differences(DID)method.The results showed that HSFC significantly increased total grain production,which is robust to various checks.HSFC increased grain yield through three potential mechanisms.First,it could increase the grain replanting index.Second,it could effectively reduce yield loss due to droughts and floods.Last,HSFC could strengthen the cultivated land by renovating the low-and medium-yielding fields.Heterogeneity analysis found that the HSFC farmland showed a significant increase in grain yield only in the main grain-producing areas and balanced areas.In addition,HSFC significantly increased the yields of rice,wheat,and maize while leading to a reduction in soybean yields.The findings suggest the government should continue to promote HSFC,improve construction standards,and strictly control the“non-agriculturalization”and“non-coordination”of farmland to increase grain production further.At the same time,market mechanisms should be used to incentivize soybean farming,improve returns and stabilize soybean yields. 展开更多
关键词 high-standard farmland farmland construction food security food production area DIFFERENCE-IN-DIFFERENCES
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Plastic mulch increases dryland wheat yield and water-use productivity,while straw mulch increases soil water storage 被引量:1
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作者 Hubing Zhao Guanfei Liu +5 位作者 Yingxia Dou Huimin Yang Tao Wang Zhaohui Wang Sukhdev Malhi Adnan Anwar Khan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期3174-3185,共12页
Amplifying drought stress and high precipitation variability impair dryland wheat production.These problems can potentially be minimized by using plastic mulch(PM)or straw mulch(SM).Therefore,wheat grain yield,soil wa... Amplifying drought stress and high precipitation variability impair dryland wheat production.These problems can potentially be minimized by using plastic mulch(PM)or straw mulch(SM).Therefore,wheat grain yield,soil water storage,soil temperature and water-use productivity of PM and SM treatments were compared with no mulch(CK)treatment on dryland wheat over a period of eight seasons.Compared to the CK treatment,PM and SM treatments on average significantly increased grain yield by 12.6 and 10.5%,respectively.Compared to the CK treatment,SM treatment significantly decreased soil daily temperature by 0.57,0.60 and 0.48℃ for the whole seasons,growing periods and summer fallow periods,respectively.In contrast,compared to the CK treatment,PM treatment increased soil daily temperature by 0.44,0.51 and 0.27℃ for the whole seasons,growing periods and summer fallow periods,respectively.Lower soil temperature under SM allowed greater soil water storage than under PM.Soil water storage pre-seeding was 17%greater under the SM than under the PM treatment.Soil water storage post-harvest was similar for the PM and SM treatments,but evapotranspiration was 4.5%higher in the SM than in the PM treatment.Consequently,water-use productivity was 6.6%greater under PM than under the SM treatment.Therefore,PM treatment increased dryland wheat yield and water-use productivity,while straw mulch increased soil water storage. 展开更多
关键词 plastic mulch soil water storage straw mulch water-use productivity winter wheat
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Simulation of the Ecosystem Productivity Responses to Aerosol Diffuse Radiation Fertilization Effects over the Pan-Arctic during 2001–19 被引量:1
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作者 Zhiding ZHANG Xu YUE +3 位作者 Hao ZHOU Jun ZHU Yadong LEI Chenguang TIAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期84-96,共13页
The pan-Arctic is confronted with air pollution transported from lower latitudes.Observations have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).Whil... The pan-Arctic is confronted with air pollution transported from lower latitudes.Observations have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).While such DRFEs have been explored at low to middle latitudes,the aerosol impacts on pan-Arctic ecosystems and the contributions by anthropogenic and natural emission sources remain less quantified.Here,we perform regional simulations at 0.2o×0.2ousing a well-validated vegetation model(Yale Interactive terrestrial Biosphere,YIBs)in combination with multi-source of observations to quantify the impacts of aerosol DRFEs on the net primary productivity(NPP)in the pan-Arctic during 2001-19.Results show that aerosol DRFEs increase pan-Arctic NPP by 2.19 Pg C(12.8%)yr^(-1)under clear-sky conditions,in which natural and anthropogenic sources contribute to 8.9% and 3.9%,respectively.Under all-sky conditions,such DRFEs are largely dampened by cloud to only 0.26 Pg C(1.24%)yr^(-1),with contributions of 0.65% by natural and 0.59% by anthropogenic species.Natural aerosols cause a positive NPP trend of 0.022% yr^(-1)following the increased fire activities in the pan-Arctic.In contrast,anthropogenic aerosols induce a negative trend of-0.01% yr^(-1)due to reduced emissions from the middle latitudes.Such trends in aerosol DRFEs show a turning point in the year of 2007 with more positive NPP trends by natural aerosols but negative NPP trends by anthropogenic aerosols thereafter.Though affected by modeling uncertainties,this study suggests a likely increasing impact of aerosols on terrestrial ecosystems in the pan-Arctic under global warming. 展开更多
关键词 diffuse radiation fertilization effects anthropogenic aerosols natural aerosols pan-Arctic net primary productivity
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Effects of Maillard reaction and its product AGEs on aging and age-related diseases 被引量:1
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作者 Huan Peng Yuqi Gao +4 位作者 Chenye Zeng Rui Hua Yannan Guo Yida Wang Zhao Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1118-1134,共17页
Maillard reaction(MR)is a non-enzymatic browning reaction commonly seen in food processing,which occurs between reducing sugars and compounds with amino groups.Despite certain advantages based on Maillard reaction pro... Maillard reaction(MR)is a non-enzymatic browning reaction commonly seen in food processing,which occurs between reducing sugars and compounds with amino groups.Despite certain advantages based on Maillard reaction products(MRPs)found in some food for health and storage application have appeared,however,the MR occurring in human physiological environment can produce advanced glycation end products(AGEs)by non-enzymatic modification of macromolecules such as proteins,lipids and nucleic acid,which could change the structure and functional activity of the molecules themselves.In this review,we take AGEs as our main object,on the one hand,discuss physiologic aging,that is,age-dependent covalent cross-linking and modification of proteins such as collagen that occur in eyes and skin containing connective tissue.On the other hand,pathological aging associated with autoimmune and inflammatory diseases,neurodegenerative diseases,diabetes and diabetic nephropathy,cardiovascular diseases and bone degenerative diseases have been mainly proposed.Based on the series of adverse effects of accelerated aging and disease pathologies caused by MRPs,the possible harm caused by some MR can be slowed down or inhibited by artificial drug intervention,dietary pattern and lifestyle control.It also stimulates people's curiosity to continue to explore the potential link between the MR and human aging and health,which should be paid more attention to for the development of life sciences. 展开更多
关键词 Maillard reaction Advanced glycation end products Physiologic aging Pathological aging Drug intervention
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High-rate electrochemical H_(2)O_(2) production over multimetallic atom catalysts under acidic–neutral conditions 被引量:1
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作者 Yueyu Tong Jiaxin Liu +5 位作者 Bing-Jian Su Jenh-Yih Juang Feng Hou Lichang Yin Shi Xue Dou Ji Liang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期44-62,共19页
Hydrogen peroxide(H_(2)O_(2))production by the electrochemical 2-electron oxygen reduction reaction(2e−ORR)is a promising alternative to the energy-intensive anthraquinone process,and single-atom electrocatalysts show... Hydrogen peroxide(H_(2)O_(2))production by the electrochemical 2-electron oxygen reduction reaction(2e−ORR)is a promising alternative to the energy-intensive anthraquinone process,and single-atom electrocatalysts show the unique capability of high selectivity toward 2e−ORR against the 4e−one.The extremely low surface density of the single-atom sites and the inflexibility in manipulating their geometric/electronic configurations,however,compromise the H_(2)O_(2) yield and impede further performance enhancement.Herein,we construct a family of multiatom catalysts(MACs),on which two or three single atoms are closely coordinated to form high-density active sites that are versatile in their atomic configurations for optimal adsorption of essential*OOH species.Among them,the Cox–Ni MAC presents excellent electrocatalytic performance for 2e−ORR,in terms of its exceptionally high H_(2)O_(2) yield in acidic electrolytes(28.96 mol L^(−1) gcat.^(−1) h^(−1))and high selectivity under acidic to neutral conditions in a wide potential region(>80%,0–0.7 V).Operando X-ray absorption and density functional theory analyses jointly unveil its unique trimetallic Co2NiN8 configuration,which efficiently induces an appropriate Ni–d orbital filling and modulates the*OOH adsorption,together boosting the electrocatalytic 2e−ORR capability.This work thus provides a new MAC strategy for tuning the geometric/electronic structure of active sites for 2e−ORR and other potential electrochemical processes. 展开更多
关键词 hydrogen peroxide production multiatom catalysts operando X-ray adsorption spectrum reaction mechanism tendency structure-property relation
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