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Laser Powder Bed Fusion of Multifunctional Bio-inspired Vertical Honeycomb Sandwich Structures:For the Application of Lightweight Bipolar Plates of Proton Exchange Membrane Fuel Cells
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作者 Kaijie Lin Yong Xu +3 位作者 Dongdong Gu Junhao Shan Keyu Shi Wanli Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第5期60-75,共16页
The bipolar plate(BPP)is a crucial component of proton exchange membrane fuel cells(PEMFC).However,the weight of BPPs can account for around 80%of a PEMFC stack,posing a hindrance to the commercialization of PEMFCs.Th... The bipolar plate(BPP)is a crucial component of proton exchange membrane fuel cells(PEMFC).However,the weight of BPPs can account for around 80%of a PEMFC stack,posing a hindrance to the commercialization of PEMFCs.Therefore,the lightweight design of BPPs should be considered as a priority.Honeycomb sandwich structures meet some requirements for bipolar plates,such as high mechanical strength and lightweight.Animals and plants in nature provide many excellent structures with characteristics such as low density and high energy absorption capacity.In this work,inspired by the microstructures of the Cybister elytra,a novel bio-inspired vertical honeycomb sandwich(BVHS)structure was designed and manufactured by laser powder bed fusion(LPBF)for the application of lightweight BPPs.Compared with the conventional vertical honeycomb sandwich(CVHS)structure formed by LPBF under the same process parameters setting,the introduction of fractal thin walls enabled self-supporting and thus improved LPBF formability.In addition,the BVHS structure exhibited superior energy absorption(EA)capability and bending properties.It is worth noting that,compared with the CVHS structure,the specific energy absorption(SEA)and specific bending strength of the BVHS structure increased by 56.99%and 46.91%,respectively.Finite element analysis(FEA)was employed to study stress distributions in structures during bending and analyze the influence mechanism of the fractal feature on the mechanical properties of BVHS structures.The electrical conductivity of structures were also studied in this work,the BVHS structures were slightly lower than the CVHS structure.FEA was also conducted to analyze the current flow direction and current density distribution of BVHS structures under a constant voltage,illustrating the influence mechanism of fractal angles on electrical conductivity properties.Finally,in order to solve the problem of trapped powder inside the enclosed unit cells,a droplet-shaped powder outlet was designed for LPBF-processed components.The number of powder outlets was optimized based on bending properties.Results of this work could provide guidelines for the design of lightweight BPPs with high mechanical strength and high electrical conductivity. 展开更多
关键词 Lightweight bipolar plates Bio-inspired honeycomb sandwich structures Laser powder bed fusion Forming quality Bending properties Electrical conductivity
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Influence of Anthesis Date and Boll Branch Position on Qualities and Super-molecular Structure of Cotton Fiber
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作者 SHAN Shi-hua, SHI Pei, SUN Xue-zhen, ZHOU Zhi-guo and BIAN Dong-cai(Agronomy Department of Shandong Agricultural University, Taian 271018 , P. R . China Tianjin Institute of Textile , Tianjin 300160 , P.R. China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第6期636-641,共6页
The influences of the anthesis date and the fruiting branch positions on parameters of cotton fiber quality and super-molecular structure were studied. Fiber quality parameters, such as cotton fiber length, micronair,... The influences of the anthesis date and the fruiting branch positions on parameters of cotton fiber quality and super-molecular structure were studied. Fiber quality parameters, such as cotton fiber length, micronair, maturity and fiber strength deteriorated with postponing the anthesis date and decreasing temperature. When anthesis happened on the same date, the fruiting branch positions affected the fiber quality parameters, and the fiber quality parameters of the lower portion turned out to be higher than that of the upper portion, although the difference was insignificant. The super-molecular structure of the lower portion turned out to be superior to that of the upper portion at the early anthesis date and high temperature, which is in accordance with what was mentioned above, but the fruiting branch positions did not affect the impact of the anthesis date on the super-molecular structure. 展开更多
关键词 COTTON Anthesis date Fruiting branch positions Fiber qualities Super-molecular structure
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The Effect of High Temperature after Anthesis on Rice Quality and Starch Granule Structure of Endosperm 被引量:6
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作者 Zhang Guilian Liao Bin +1 位作者 Li Bo Cai Zhihuan 《Meteorological and Environmental Research》 CAS 2016年第3期72-75,共4页
To ascertain the effect mechanism of high temperature after anthesis on rice quality, the experiment was conducted with two rice lines, the heat-tolerant line 996 and heat-sensitive line 4628, with high temperature an... To ascertain the effect mechanism of high temperature after anthesis on rice quality, the experiment was conducted with two rice lines, the heat-tolerant line 996 and heat-sensitive line 4628, with high temperature and optimal temperature in the growth chamber to investigate the effect of high temperature stress after anthesis on rice appearance quality, milling quality, cooking and eating quality and starch granule structure of endo- sperm. The result showed that milled rice rate, head rice rate, amylose content and gel consistency of both lines decreased under high temperature stress after anthesis, while the ratio of grain length to width, chalky rate, chalkiness, protein content increased. Under high temperature treatments, gelatinization temperature, final viscosity, set back and peak time increased, breakdown decreased, Mg content and K content increased, Mg/K ra- tio decreased. Under same treatment, the extent of rice quality of heat tolerant line 996 affected by high temperature was lower than that of heat sensitive line 4628. Under high temperature stress after anthesis, starch granule arranged untightly, most of starch granules existed in the form of a single starch endosperm, refractive index decreased, transparency reduced, and led to the formation of chalk. Under high temperature stress af- ter anthesis, the increase of protein content, the decrease of Mg/K, the changes of rice RVA profile characteristics and starch granule structure of endosperm could be the main reason for the decrease of rice cooking and eating quality and appearance quality. 展开更多
关键词 High temperature stress after anthesis Rice quality ENDOSPERM Starch granule structure China
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Factor input structure,environmental policies,and the export quality upgrade:a perspective of heterogeneity 被引量:3
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作者 Jiayue Liu Jing Xie 《Chinese Journal of Population,Resources and Environment》 2018年第1期67-76,共10页
In the analysis of how environmental regulation affects the comparative advantage of trade,existing literature ignores industry's inherent heterogeneity, which draws remarkably different conclusions. In view of th... In the analysis of how environmental regulation affects the comparative advantage of trade,existing literature ignores industry's inherent heterogeneity, which draws remarkably different conclusions. In view of this, the paper analyzed the mechanism of environmental regulation on the export quality of different industries from the perspective of factor input structure heterogeneity. Based on the panel data of China's manufacturing industry, the paper used the system generalized method of moments method to examine the heterogeneity influence of environmental regulation on manufacturing export quality. The study found that, first, environmental regulation affected the export quality upgrade of the manufacturing sector through offset effect and compensation effect, and the direction of the impact would mainly depend on the industry's factor input structure. Second, for industries with larger fixed-asset investment(FAI) ratio in the factor input structure, the current environmental regulation policy was not conducive to the export quality upgrading of the industries. However, there was a significant U-shaped dynamic relationship between them. As environmental regulations became stricter, when regulatory stringency went beyond the inflection point, the policy would promote the upgrading of export quality. But for industries with smaller proportion of FAI, environmental regulation exerted a favorable impact on the export quality upgrade, following a J-shaped marginal growth curve.Third, for industries with different factor input structure, their export quality had been effectively upgraded as expected by factors like human capital investment, independent R&D, technology introduction, and foreign direct investment; but raising per capita capital stock and expanding enterprise size did not produce significant direct impact on export quality upgrade. These conclusions remained robust after using different measurement methods and replacing with other variables. Therefore, this paper suggests that governments should take industry heterogeneity into consideration and formulate differentiated hierarchical environmental policies.Besides, they should strengthen the enforcement of the current environmental regulation policies. By doing so, enterprises are forced to improve their technology and product quality so that they can better cope with rising compliance costs, eliminate backward industries, and resolve excess capacity. In this way, the economic structure would be transformed and upgraded from the supply side. 展开更多
关键词 Environmental regulation export quality factor input structure industry heterogeneity
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Combined Insights from Leachate Structure and Microstructure Characteristics for Eating Quality of Convenience Rice Processed by Super-Heated and Pressurized Steam Technologies
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作者 Mingyo HA Hyo-Young JEONG +1 位作者 Ju Hun LEE Hyun-Jung CHUNG 《Rice science》 SCIE CSCD 2024年第4期475-488,I0035,I0036,共16页
Convenience rice has become widely popular due to its easy availability for cooking. This study investigated the starch structure and composition of leachate and the microstructure of reheated convenience rice using n... Convenience rice has become widely popular due to its easy availability for cooking. This study investigated the starch structure and composition of leachate and the microstructure of reheated convenience rice using novel processing technologies: super-heated steaming(SHS), auto-electric cooking(AEC), and pressurized-steam cooking(PSC). Additionally, the effect of two different target water contents(58% and 63%) was also evaluated. The PSC_63% sample had the highest total solids and amylopectin amount in the leachate. The amylopectin amount in the leachate differed significantly based on the targeted water content. Morphological characterization revealed that the swelling of starch and the coated layer on the surface of rice grains were most pronounced in the PSC_63% sample due to the pressure processing. The textural hardness of the AEC_58% sample was much higher than that of the other samples. The PSC_63% sample had the highest textural adhesiveness value, which can be attributed to the highest amylopectin amount in the leachate. Sensory characterization showed that the PSC_63% sample had the highest glossiness, whiteness, moistness, and overall acceptability. The principal component analysis score plots presented substantial differences in the leachate and textural and sensory characteristics of reheated convenience rice among the different processing technologies. 展开更多
关键词 reheated convenience rice starch structure LEACHATE multi-scale structure eating quality processing technology
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Effects of water deficit and high N fertilization on wheat storage protein synthesis,gluten secondary structure,and breadmaking quality 被引量:4
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作者 Junxian Liu Junwei Zhang +2 位作者 Gengrui Zhu Dong Zhu Yueming Yan 《The Crop Journal》 SCIE CSCD 2022年第1期216-223,共8页
The content and composition of wheat storage proteins are the major determinants of dough rheological properties and breadmaking quality and are influenced by cultivation conditions.This study aimed to investigate the... The content and composition of wheat storage proteins are the major determinants of dough rheological properties and breadmaking quality and are influenced by cultivation conditions.This study aimed to investigate the effects of water deficit and high N-fertilizer application on wheat storage protein synthesis,gluten secondary structure,and breadmaking quality.Reverse-phase ultrahigh-performance liquid chromatography analysis showed that storage protein and gluten macropolymer accumulation was promoted under both independent applications and a combination of water-deficit and high N-fertilizer treatments.Fourier-transform infrared spectroscopy showed that water deficit and high N-fertilizer treatments generally improved protein secondary structure formation and lipid accumulation,and reduced flour moisture.In particular,high N-fertilizer application increasedβ-sheet content by 10.4%and the combination of water-deficit and high N-fertilizer treatments increased random coil content by 7.6%.These changes in gluten content and secondary structure led to improved dough rheological properties and breadmaking quality,including superior loaf internal structure,volume,and score.Our results demonstrate that moderately high N-fertilizer application under drought conditions can improve gluten accumulation,gluten secondary structure formation,and baking quality. 展开更多
关键词 Water deficit High N-fertilizer Storage proteins Gluten structure Breadmaking quality
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Prediction of multiscale laminae structure and reservoir quality in fine-grained sedimentary rocks:The Permian Lucaogou Formation in Jimusar Sag,Junggar Basin 被引量:4
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作者 Xiao-Jiao Pang Gui-Wen Wang +8 位作者 Li-Chun Kuang Jin Lai Yang Gao Yi-Di Zhao Hong-Bin Li Song Wang Meng Bao Shi-Chen Liu Bing-Chang Liu 《Petroleum Science》 SCIE CAS CSCD 2022年第6期2549-2571,共23页
Fine-grained sedimentary rocks have become a research focus as important reservoirs and source rocks for tight and shale oil and gas.Laminae development determines the accumulation and production of tight and shale oi... Fine-grained sedimentary rocks have become a research focus as important reservoirs and source rocks for tight and shale oil and gas.Laminae development determines the accumulation and production of tight and shale oil and gas in fine-grained rocks.However,due to the resolution limit of conventional logs,it is challenging to recognize the features of centimeter-scale laminae.To close this gap,complementary studies,including core observation,thin section,X-ray diffraction(XRD),conventional log analysis,and slabs of image logs,were conducted to unravel the centimeter-scale laminae.The laminae recognition models were built using well logs.The fine-grained rocks can be divided into laminated rocks(lamina thickness of<0.01 m),layered rocks(0.01-0.1 m),and massive rocks(no layer or layer spacing of>0.1 m)according to the laminae scale from core observations.According to the mineral superposition assemblages from thin-section observations,the laminated rocks can be further divided into binary,ternary,and multiple structures.The typical mineral components,slabs,and T2spectrum distributions of various lamina types are unraveled.The core can identify the centimeter-millimeter-scale laminae,and the thin section can identify the millimeter-micrometer-scale laminae.Furthermore,they can detect mineral types and their superposition sequence.Conventional logs can identify the meter-scale layers,whereas image logs and related slabs can identify the laminae variations at millimeter-centimeter scales.Therefore,the slab of image logs combined with thin sections can identify laminae assemblage characteristics,including the thickness and vertical assemblage.The identification and classification of lamina structure of various scales on a single well can be predicted using conventional logs,image logs,and slabs combined with thin sections.The layered rocks have better reservoir quality and oil-bearing potential than the massive and laminated rocks.The laminated rocks’binary lamina is better than the ternary and multiple layers due to the high content of felsic minerals.The abovementioned results build the prediction model for multiscale laminae structure using well logs,helping sweet spots prediction in the Permian Lucaogou Formation in the Jimusar Sag and fine-grained sedimentary rocks worldwide. 展开更多
关键词 Fine-grained sedimentary rocks Mineral composition Multiscale laminae structure Reservoir quality Image logs Lucaogou formation
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Wastewater treatment performance and microbial community structure in the constructed wetland under double-pressure of low temperature and Ag NPs exposure 被引量:2
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作者 Huang Juan Cao Meifang +2 位作者 Ma Yixuan Liu Jialiang Guan Wenzhu 《Journal of Southeast University(English Edition)》 EI CAS 2022年第3期291-299,共9页
To investigate the effects of silver nanoparticles(Ag NPs)and low temperature double-pressure on the wastewater treatment efficacy and the microbial community structure of constructed wetlands,a pilot-scale vertical f... To investigate the effects of silver nanoparticles(Ag NPs)and low temperature double-pressure on the wastewater treatment efficacy and the microbial community structure of constructed wetlands,a pilot-scale vertical flow constructed wetland was set up to treat synthetic wastewater under laboratory conditions.By measuring the effluent concentration of ammonia nitrogen(NH_(4)^(+)-N),total nitrogen(TN),total phosphorus(TP),chemical oxygen demand(COD),and the diversity,richness,and community structure of microorganisms of the upper and lower soil layers in the wetland,the nutrient removal effect of the constructed wetland and the changes in the microflora of the soil layer were studied.The results reveal that the correlation coefficients between the removal rates of TN and NH_(4)^(+)-N and the temperature are 0.463 and 0.692,respectively,indicating a significant positive correlation.From the warm to the cold season,both the diversity and richness of microorganisms in the lower soil layer of wetlands are inhibited under the double-pressure of Ag NPs and low temperature,and the abundances of the denitrogenation functional bacteria such as Candidatus nitrososphaera,Sulfuritalea,Anaeromyxobacter,Candidatus solibacter,Nitrospira,and Zoogloea are altered.Low temperature and Ag NPs exposure can thus affect the wastewater treatment performance of constructed wetlands,possibly because of the seasonal changes of the microflora. 展开更多
关键词 silver nanoparticles constructed wetland wastewater treatment low temperature microbial community structure water quality
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Research on the Construction of Drug Inspection Evaluation Indicator System
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作者 Hu Di Liao Ping +3 位作者 Zhu Xin Dai Yuemin Ge Yuanyuan Chen Yuwen 《Asian Journal of Social Pharmacy》 2024年第4期327-343,共17页
Objective To study a way to establish a drug inspection evaluation system in China.Methods Through literature research,behavioral event interviews,Delphi expert interviews,and other methods,the theory of“threedimensi... Objective To study a way to establish a drug inspection evaluation system in China.Methods Through literature research,behavioral event interviews,Delphi expert interviews,and other methods,the theory of“threedimensional quality structure model”was used to extract,screen,and construct a set of evaluation indicator system for drug inspection,including 3 first-level indicators,11 second-level indicators,and 47 third-level indicators.Results and Conclusion An effective management tool to evaluate the quality of drug inspection has not yet been formed in China.According to the requirements of laws,regulations,and departmental rules,combined with the mature drug inspection mechanism of international drug regulatory agencies or organizations and the international quality management theory,some management tools are put forward to improve the quality system of drug supervision. 展开更多
关键词 drug inspection QUALITY evaluation indicator system three-dimensional quality structure model DELPHI
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Quality Analyses of Fine Structures Transfer in the Photorealistic Images
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作者 S. V. Sai I. S. Sai N. Yu. Sorokin 《Open Journal of Applied Sciences》 2013年第1期6-9,共4页
This work presents method of the quality analyses of the photorealistic images. Developed method utilizes proposed criteria of image definition quality for fine details. Presented method has the following significant ... This work presents method of the quality analyses of the photorealistic images. Developed method utilizes proposed criteria of image definition quality for fine details. Presented method has the following significant property: the quality estimation is provided without test images or patterns. Algorithm for search and recognition of fine structures in the photorealistic images using the predefined criterion is considered. 展开更多
关键词 Image QUALITY ANALYSES SEARCH Algorithm FINE structures Recognition
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The Moderating Role of Ownership Structure on the Relation between Board Independence and Voluntary Financial Disclosure: An Analysis of Italian Listed Company
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作者 Luigi Lepore Sabrina Pisano +1 位作者 Gabriella D’Amore Carmela Di Guida 《Journal of Modern Accounting and Auditing》 2019年第7期323-342,共20页
Voluntary disclosure and corporate governance variables, such as board independence and ownership structure are considered mechanisms useful to reduce information asymmetries between competing parties of the firms. Th... Voluntary disclosure and corporate governance variables, such as board independence and ownership structure are considered mechanisms useful to reduce information asymmetries between competing parties of the firms. This paper aims at investigating both the relationship between board independence and the quality of voluntary financial disclosure and how previous relationship is moderated by the level of ownership concentration. The analysis has been conducted on a sample of Italian non-financial listed companies. The results show that there is a positive and significant relationship between board independence and the quality of voluntary financial disclosure provided by companies. In addition, the findings reveal that ownership concentration plays a relevant moderating role in previous relationship. The results highlight the necessity to consider the interaction effects of different governance mechanisms, when studying corporate governance effectiveness. 展开更多
关键词 board INDEPENDENCE financial DISCLOSURE quality OWNERSHIP structure
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Characteristics of the Ownership Structure of Chinese Listed Companies and Its Effect on Financial Reports Quality
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作者 Weidong Meng Fengming Tao 《Chinese Business Review》 2003年第1期77-81,共5页
Ownership structure is brand-new to the reform of Chinese state-owned enterprises, and also a problem that urgently need to study. Because the reform wasn't entire, the ownership structure of Chinese listed companies... Ownership structure is brand-new to the reform of Chinese state-owned enterprises, and also a problem that urgently need to study. Because the reform wasn't entire, the ownership structure of Chinese listed companies looks freakish. That is to say, the ownership is highly concentrated in the state, who has just no tangible rights to control the business, which results in "insider control", "owner absence", "duality of manager and chairman", and so on. At the same time, such an ownership structure is unavoidable to supply inducement to the people who has relative benefits in it, and it eventually affects the quality of their financial reports. This paper empirically studies the ownership structure of Chinese listed companies and their characteristics in the actual situation, and finally puts forward some suggestions on how to improve the quality of the financial reports from the ownership structure approach. 展开更多
关键词 ownership structures the quality of financial report
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Probabilistic method and its application for evaluating carbonation life of newly-built concrete structures 被引量:2
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作者 巴明芳 钱春香 黄雷 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期578-581,共4页
In order to evaluate the carbonation life of newly-built concrete structures,two kinds of nondestructive methods are adopted to test the thickness of the concrete cover and the ultrasonic velocity of two newly-built t... In order to evaluate the carbonation life of newly-built concrete structures,two kinds of nondestructive methods are adopted to test the thickness of the concrete cover and the ultrasonic velocity of two newly-built tunnel structures.Simultaneously a probabilistic method is proposed based on the relationship between the accelerated carbonation rate and the ultrasonic velocity.This proposed method is applied to evaluate the carbonation related lives of two newly-built tunnels and the results indicate that even under nearly the same environment and CO2 combining conditions,there exits a big difference in the probabilistic carbonation lives between the two tunnels;i.e.,the probabilistic lives of Tunnel A and Tunnel B are 94.0% and 82.3% and the corresponding maximum discrepancies are 11.6% and 27.0%,respectively.Thus,it can be concluded that the scattered quality of the concrete cover is attributed to the differences in construction technique,which eventually leads to the diversity in the evaluated probabilistic carbonation lives of the two tunnels. 展开更多
关键词 probabilistic carbonation life newly-built structure concrete-cover quality
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The Influence of the Urban-Rural Income Disparity on the Industrial Structure—Taking the Yangtze River Delta Region as an Example
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作者 Yan Chen Yuanyuan Sun Wanbin Li 《Open Journal of Statistics》 2022年第3期303-323,共21页
In this paper, the effect of the mediation effect is mainly used to test and analyze the regression model, and most scholars have studied the impact of the modernization of the industrial structure on the income gap. ... In this paper, the effect of the mediation effect is mainly used to test and analyze the regression model, and most scholars have studied the impact of the modernization of the industrial structure on the income gap. However, this paper is from another perspective, based on the social background of high-quality development, the main study is the impact mechanism of urban and rural income gap on the industrial structure, taking the Yangtze River Delta as the main research object, and specifically selecting 22 central cities in the Yangtze River Delta region, which is also one of the highlights of this study. The regression model is constructed by using the intermediary effect, and the four intermediary variables of fiscal expenditure (M<sub>1</sub>), fixed asset investment (M<sub>2</sub>), number of patent applications (M<sub>3</sub>), and total import and export (M<sub>4</sub>) are selected, which represent the role of the government, fixed asset investment, scientific and technological level and opening-up level, and study and analyze the inherent influence mechanism between each variable. Before doing specific research, I consulted the papers and literature of many other outstanding scholars, among which Cheng Yuhong and Cheng Chi’s “The Influence Mechanism of industrial structure of urban and rural income gap” [1] has great reference value for this paper. According to the research results, under the background of high-quality development in the Yangtze River Delta region, the expansion of the income gap between urban and rural areas will inhibit the upgrading of the industrial structure, so it is necessary to focus on building a new type of urbanization, accelerating the construction of an urban innovation system, optimizing the rural employment structure to narrow the income gap between urban and rural areas, and providing impetus for the continuous upgrading of the industrial structure. 展开更多
关键词 Income Gap Between Urban and Rural Areas Industrial structure Upgrading High-Quality Development Normalization of the Epidemic Yangtze River Delta Region Mediation Effect Model SPSS
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The impact of male overweight on semen quality and outcome of assisted reproduction 被引量:9
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作者 Lise Thomsen Peter Humaidan +1 位作者 Leif Bungum Mona Bungum 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第5期749-754,I0010,共7页
It is well-documented that male overweight and obesity causes endocrine disorders that might diminish the male reproductive capacity; however, reports have been conflicting regarding the influence of male body mass in... It is well-documented that male overweight and obesity causes endocrine disorders that might diminish the male reproductive capacity; however, reports have been conflicting regarding the influence of male body mass index (BMI) on semen quality and the outcome of assisted reproductive technology (ART). The aim of this study was to investigate whether increased male BMI affects sperm quality and the outcome of assisted reproduction in couples with an overweight or obese man and a non-obese partner. Data was prospectively collected from 612 infertile couples undergoing ART at a Danish fertility center. Self-reported information on paternal height and weight were recorded and BMI was calculated. The men were divided into four BMI categories: underweight BMI 〈 20 kgm^-2, normal BMI 20-24.9 kg m^-2, overweight BMI 25-29.9 kgm^-2 and obese BMI 〉 30 kgm^-2. Conventional semen analysis was performed according to the World Health Organization guideline and sperm DNA integrity was analyzed by the Sperm Chromatin Structure Assay (SCSA). No statistically significant effect of male BMI was seen on conventional semen parameters (sperm concentration, total sperm count, seminal volume and motility) or on SCSA-results. Furthermore, the outcome of ART regarding fertilization rate, number of good quality embryos (GQE), implantation and pregnancy outcome was not influenced by the increasing male BMIo 展开更多
关键词 assisted reproductive technology body mass index male obesity sperm chromatin structure assay sperm quality
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Control of diffuse P-pollutants by multiple buffer/detention structures by Yuqiao Reservoir, North China 被引量:5
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作者 WANGXia-hui YINCheng-qing SHANBao-qing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第4期616-620,共5页
A case study on the transport process of agricultural diffuse P-pollutants was conducted in an experimental watershed locating in the north bank of Yuqiao Reservoir during 2001 and 2002. It was found that diversified ... A case study on the transport process of agricultural diffuse P-pollutants was conducted in an experimental watershed locating in the north bank of Yuqiao Reservoir during 2001 and 2002. It was found that diversified artificial and natural buffer/detention landscape structures distributing along the ephemeral stream channel in this watershed played an important role of pollutants removal on downstream water quality, especially they have control effect on the diffuse P-pollutants transport process. Surface flow velocity was reduced sharply after passing through these structures. During continuous runoff events, the removal rate of TSS, TP, TDP, DRP by the whole system were 66.7%, 60.7%, 48.4%, and 43.3%, respectively. During discontinuous runoff events, removal rate of pollutants by the whole system was higher due to there was no or little surface water and pollutants exported from the watershed, of which removal rate of pollutants all exceeded 99%. The statistical analysis results of runoff events(n=8) indicated that dry pond was the steadiest structure for controlling diffuse P-pollutants export. 展开更多
关键词 diffuse P-pollutants buffer/detention structures removal transport process water quality
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Framework system and research flow of uncertainty in 3D geological structure models 被引量:7
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作者 ZHU, Liangfeng ZHUANG, Zhiyi 《Mining Science and Technology》 EI CAS 2010年第2期306-311,共6页
Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error... Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error detection and dynamic correction in 3D geological structure models,we have reviewed the current situation and development trends in 3D geological modeling.The main context of uncertainty in 3D geological structure models is discussed.Major research issues and a general framework system of uncertainty in 3D geological structure models are proposed.We have described in detail the integration of development practices of 3D geological modeling systems,as well as the implementation process for uncertainty evaluation in 3D geological structure models.This study has laid the basis to build theoretical and methodological systems for accuracy assessment and error correction in 3D geological models and can assist in improving 3D modeling techniques under complex geological conditions. 展开更多
关键词 3D geological structure model model quality UNCERTAINTY 3D geological modeling
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Spatial and seasonal pattern of macrozoobenthic assemblages and the congruence in water quality bioassessment using different taxa in artificial Mingzhu Lake in Shanghai 被引量:3
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作者 胡忠军 贾茜茜 +2 位作者 陈细华 张颖 刘其根 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第5期928-936,共9页
The spatial and seasonal pattern of macrozoobenthic structure and its relationship with environmental factors were studied from July 2006 to April 2008 in Mingzhu Lake,Chongming Island,Shanghai at the Changjiang River... The spatial and seasonal pattern of macrozoobenthic structure and its relationship with environmental factors were studied from July 2006 to April 2008 in Mingzhu Lake,Chongming Island,Shanghai at the Changjiang River mouth.The congruences in water quality bioassessment based on diversity and biotic indices and using different taxonomic categories were also explored to find the best assessment method of water quality for the lake.All major structural characteristics of macrozoobenthic community,including species composition,abundance,biomass and four biomass-based diversity indices(Shannon's diversity,Simpson's diversity,Pielou's evenness and Simpson's evenness index) fluctuated significantly in season but in space.The above four abundance-based diversity indices plus abundance-based Margalef's richness index did not display significant spatial variations;and significant seasonal differences were found in three indices only.Water temperature was the key environmental factor responsible for macrozoobenthic spatio-temporal distribution patterns.Water quality assessed by Shannon's index(H_a') and biological pollution index(BPI) rather than the other four biotic indices were consistent with those by trophic state index(TSI).Results from chironomids and oligochaetes did not always agree to those from the whole community when H_a' or Hilsenhoff biotic index was applied to bioassessment.Therefore,combining multiple indices and avoiding a single taxonomic category to assess water quality are strongly recommended and in Mingzhu Lake using a mixture of H_a' and BPI will ensure the most effective investigation of water quality.Our results also show that the main structural characteristics of macrozoobenthic communities in the small lake may display consistent spatial patterns. 展开更多
关键词 Chongming Island benthic macroinvertebrate community structure BIODIVERSITY spatial and seasonal variation water quality bioassessment
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Dietary bamboo leaf flavonoids improve quality and microstructure of broiler meat by changing untargeted metabolome 被引量:6
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作者 Guangtian Cao Huixian Wang +6 位作者 Yang Yu Fei Tao Huijuan Yang Shenglan Yang Ye Qian Hui Li Caimei Yang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第4期1514-1527,共14页
Background Dietary bamboo leaf flavonoids(BLFs)are rarely used in poultry production,and it is unknown whether they influence meat texture profile,perceived color,or microstructure.Results A total of 720 one-day-old A... Background Dietary bamboo leaf flavonoids(BLFs)are rarely used in poultry production,and it is unknown whether they influence meat texture profile,perceived color,or microstructure.Results A total of 720 one-day-old Arbor Acres broilers were supplemented with a basal diet with 20 mg bacitracin/kg,50 mg BLFs/kg,or 250 mg BLFs/kg or without additions.Data showed that the dietary BLFs significantly(P<0.05)changed growth performance and the texture profile.In particular,BLFs increased birds’average daily gain and average daily feed intake,decreased the feed:gain ratio and mortality rate,improved elasticity of breast meat,enhanced the gumminess of breast and leg meat,and decreased the hardness of breast meat.Moreover,a significant(P<0.05)increase in redness(a*)and chroma(c*)of breast meat and c*and water-holding capacity of leg meat was found in BLF-supplemented broilers compared with control broilers.In addition,BLFs supplementation significantly decreased(P<0.05)theβ-sheet ratio and serum malondialdehyde and increased theβ-turn ratio of protein secondary structure,superoxide dismutase,and glutathione peroxidase of breast meat and total antioxidant capacity and catalase of serum.Based on the analysis of untargeted metabolome,BLFs treatment considerably altered 14 metabolites of the breast meat,including flavonoids,amino acids,and organic acids,as well as phenolic and aromatic compounds.Conclusions Dietary BLFs supplementation could play a beneficial role in improving meat quality and sensory color in the poultry industry by changing protein secondary structures and modulating metabolites. 展开更多
关键词 Bamboo leaf flavonoid BROILER Meat quality METABOLOME Protein secondary structure
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Structures and Functions of Cuticular Wax in Postharvest Fruit and Its Regulation:A Comprehensive Review with Future Perspectives 被引量:4
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作者 Weijie Wu Bo Jiang +9 位作者 Ruiling Liu Yanchao Han Xiangjun Fang Honglei Mu Mohamed A.Farag Jesus Simal-Gandara Miguel A.Prieto Hangjun Chen Jianbo Xiao Haiyan Gao 《Engineering》 SCIE EI CAS CSCD 2023年第4期118-129,M0006,共13页
Cuticular wax plays a major role in the growth and storage of plant fruits.The cuticular wax coating,which covers the outermost layer of a fruit’s epidermal cells,is insoluble in water.Cuticular wax is mainly compose... Cuticular wax plays a major role in the growth and storage of plant fruits.The cuticular wax coating,which covers the outermost layer of a fruit’s epidermal cells,is insoluble in water.Cuticular wax is mainly composed of very long-chain fatty acids(VLCFAs);their derivatives,including esters,primary alcohols,secondary alcohols,aldehydes,and ketones;and triterpenoids.This complex mixture of lipids is probably biosynthesized in the epidermal cells of most plants and exuded onto the surface.Cuticular wax not only makes the fruit less susceptible to microbial infection but also reduces mechanical damage to the fruit,thereby maintaining the fruit’s commodity value.To date,research has mostly focused on the changes,function,and regulation of fruit wax before harvest,while ignoring the changes and functions of wax in fruit storage.This paper reviews on the composition,structure,and metabolic regulation of cuticular wax in fruits.It also focuses on postharvest factors affecting wax composition,such as storage temperature,relative humidity(RH),gas atmosphere,and as exogenous hormones;and the effects of wax on fruit postharvest quality,including water dispersion,fruit softening,physiological disorders,and disease resistance.These summaries may be of assistance in better understanding the changes in cuticular wax in postharvest fruit and the resulting effects on fruit quality. 展开更多
关键词 Cuticular wax structure and function POSTHARVEST Fruit quality
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