Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linka...Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linkages,the importance of marine economic net-work research is beginning to emerge.The construction of the marine economic network in China’s coastal areas is necessary to change the flow of land and sea resources and optimize regional marine economic development.Employing data from headquarters and branches of sea-related A-share listed enterprises to construct the marine economic network in China,we use social network analysis(SNA)to discuss the characteristics of its evolution as of 2010,2015,and 2020 and its governance.The following results were obtained.1)In terms of topological characteristics,the scale of the marine economic network in China’s coastal areas has accelerated and expan-ded,and the connections have become increasingly close;thus,this development has complex network characteristics.2)In terms of spatial structure,the intensity of the connection fluctuates and does not form stable development support;the group structure gradually becomes clear,but the overall pattern is fragmented;there are spatial differences in marine economic agglomeration radiation;the radi-ation effect of the eastern marine economic circle is obvious;and the polarization effect of northern and southern marine economic circles is significant.On this basis,we construct a framework for the governance of a marine economic network with the market,the government,and industry as the three governing bodies.By clarifying the driving factors and building objectives of marine economic network construction,this study aims to foster the high-quality development of China’s marine economy.展开更多
Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this limitation.Unlike most studies that concentrated on...Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this limitation.Unlike most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina ores.The results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO concentration.Fourier transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO substitution.Deconvolution of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents increased.Structural analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO substitution.However,bond strength is another important factor affecting the slag viscosity.The occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.展开更多
Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and...Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and hierarchical.Due to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding materials.Despite concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding materials.In particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be valuable.The preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and analyzed.The composite methods and fillers of various biomass materials were reviewed.this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field.展开更多
γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the ...γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface receptors.Mutations inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as well.However,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-secretase.In this review,we focus on recent studies of structural dynamic mechanisms ofγ-secretase.Different mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics simulations.While an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental findings.The approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-secretase.In addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is discussed.Finally,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations of theγ-secretase-substrate complexes.Comprehensive understanding of the functional mechanisms ofγ-secretase will greatly facilitate the rational design of effective drug molecules for treating familial Alzheimer’s disease and perhaps Alzheimer’s disease in general.展开更多
Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)materials.However,the relationship betw...Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)materials.However,the relationship between configuration and electromagnetic(EM)loss mechanism has remained elusive.Herein,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co-doped helical carbon nanotubes with ultrabroad EMWA capability.Theoretical calculation and EM simulation confirm that the orbital coupling and spin polarization of the Mn–N4–C configuration,along with cross polarization generated by the helical structure,endow the helical converters with enhanced EM loss.As a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 mm.Through precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm thickness.Furthermore,constructing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB m2.This innovative approach not only advances the understanding of metal–nonmetal co-doping but also realizes broadband EMWA,thus contributing to the development of EMWA mechanisms and applications.展开更多
Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research an...Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research and development(R D) alliances.Therefore,the first objective of this study is to investigate why there exist different organizational governance structures in managing R D alliances;the second objective of this study is to give strategic advice in choosing appropriate forms with respect to various characteristics of R D alliances.Through the theoretical lens that integrate both transaction cost economics(TCE) and the resource-based view(RBV),a model that focuses on six major factors is developed for determining governance structure choices,namely,technological uncertainty,cultural difference,asset specificity,technology complementarity,appropriability of the individual firm's know-how,and trust.An R D alliance with higher technological uncertainty,larger cultural differences,and greater concerns for protecting an individual's know-how is more likely to adopt non-integrated alliances as the governing structure.An R D alliance with a higher degree of asset-specificity,greater technology complementarity and greater trust among partnering organizations is more likely to adopt integrated alliances as the governing structure;an R D alliance in the face of lower technological uncertainty will tend to adopt integrated alliances.The more aligned the choice of the governance structure with its determinants,the better the R D alliance will perform,and vice versa.展开更多
Food safety issues constitute an international topic discussed by many scholars. Although there is an extensive body of literature on comparisons of food safety control practices across different governance structures...Food safety issues constitute an international topic discussed by many scholars. Although there is an extensive body of literature on comparisons of food safety control practices across different governance structures, these studies have been conducted mainly in terms of qualitative and descriptive analysis. In addition, little attention has been given to family farms. This study addresses the food safety control practices adopted by firms with different governance structures in China. Food safety control is expressed by the following aspects, i.e., pollution-free, green, organic, and/or geographical indication prod- ucts certification, establishment of production records, and pesticide residue testing. Three types of governance structures that engage in agricultural production are distinguished: farmer cooperatives, agricultural companies, and family farms. The food safety control practices of various governance structures are investigated based on a database that comprises 600 vegetable and fruit enterprises in Zhejiang, China. The results show that (1) pesticide residue testing is adopted by the most firms, followed by products certification, and production records are adopted by the fewest firms, and (2) agricul- tural companies adopt more food safety control practices than family farms, while farmer cooperatives adopt the fewest food safety control practices. Governance structure features of a cooperative in terms of ownership, decision-making, and income distribution are the main reasons for the low level of food safety control in the cooperative.展开更多
The purpose of this research is to examine the impact of financial distress status and corporate governance structures on the level of voluntary disclosure. We apply six independent variables, including the firm's fi...The purpose of this research is to examine the impact of financial distress status and corporate governance structures on the level of voluntary disclosure. We apply six independent variables, including the firm's financial distress status and five components of corporate governance structures, such as board independence, audit committee independence, institutional ownership, board meeting frequency, and audit committee meeting frequency. This research is carried out by examining the annual reports of 114 non-financial firms listed at the Indonesian Stock Exchange over the period of 2009-2011. To test hypotheses, we undergo two different analyses, including independent samples t-test and Multiple Linear Regression. We find that: (1) The audit committee independence and the audit committee meeting frequency have significant positive impacts on the level of voluntary disclosure; (2) The financial distress status is negatively related to the level of disclosure at various levels of significance; and (3) All the independent variables are simultaneously related to voluntary disclosure.展开更多
Corporate governance structure system, or corporate organization system, which is a management model and system on the basis that the investment and control are separate, is the rules of setting up and operating the c...Corporate governance structure system, or corporate organization system, which is a management model and system on the basis that the investment and control are separate, is the rules of setting up and operating the corporate organizations which is specified in Company laws among counties around the world. This article introduces the five parts of corporate governance structure system and discuses the function.展开更多
Facing with the enormous data scale of the civil aviation industry, the vital issue that enterprises must consider is how to manage and make use of data to play its value. In this study, the content of the governance ...Facing with the enormous data scale of the civil aviation industry, the vital issue that enterprises must consider is how to manage and make use of data to play its value. In this study, the content of the governance of big data of civil aviation is analyzed and this paper put forward the specific governance of big data resources of civil aviation to provide relevant support of the governance of big data resources of civil aviation.展开更多
Using the method of principal component analysis, the paper conducts a systematic study on the issue of how corporate governance influences capital structure. The study manifests the results that the proportion of cir...Using the method of principal component analysis, the paper conducts a systematic study on the issue of how corporate governance influences capital structure. The study manifests the results that the proportion of circulation shares, the ability that other big shareholders contend with the first biggest shareholder, the proportion of corporation-owned shares, and the frequency of directorate meetings all have a positive relationship with the liability level. Meanwhile, the concentration degree of owners' equity, the proportion of state-owned shares, the phenomenon that one person serves as both chairman of directorate and general manager, and the intensity of competition in product market are all negatively related to the level of debt. Finally, the scale of directorate, the proportion of independent directors as well as the percentage of management-owned shares have no significant relationship with the capital structure. The statistic analysis also shows that the proportion of independent directors of some Chinese listed companies does not meet the regulation of the CSRC. In addition, the paper tests the impacts of corporate operating characteristics on capital structure.展开更多
In this paper, 87 farmers' specialized cooperatives in Sichuan Province were investigated firstly, and then their governance structure was analyzed from the aspects of authority, decision-making mechanism, supervi...In this paper, 87 farmers' specialized cooperatives in Sichuan Province were investigated firstly, and then their governance structure was analyzed from the aspects of authority, decision-making mechanism, supervision mechanism and executive body based on the corporative governance structure in narrowest sense, finally corresponding policy suggestions for improving the governance structure of farmers' specialized cooperatives in Sichuan Province were put forward. It is concluded that human control is serious within farmers' specialized cooperatives; inner supervision is effective; council has great effects on governance structure; the cooperatives give limited incentive to managers.展开更多
It is generally believed in academia that there are two theoretical explanations of tunneling and financing advantage for the creation of pyramidal structure. However, there is no definitive conclusion on which explan...It is generally believed in academia that there are two theoretical explanations of tunneling and financing advantage for the creation of pyramidal structure. However, there is no definitive conclusion on which explanation holds sway. Based on non-equilibrium panel data of seven years between 2004 and 2010, this empirical study uses the product market competition variables of "inter-sector competition" and "intra-sector competition" and the hierarchy and complexity of pyramidal structure, examines the correlation between pyramidal structure of Chinese private manufacturing listed firms and product market competition and patterns of change, and reveals the major causes of pyramidal structure. Empirical result indicates that, for Chinese private manufacturing listed companies, there is a significant negative correlation between product market competition and the hierarchy and complexity of pyramidal structure, which indicates that the creation of pyramidal structure has a preference on tunneling by controlling shareholders. On the basis of further considerations on corporate tunneling and financing restraint categorization, high-tunneling firms and firms with low financing restraint demonstrate significant tunneling motivations; low-tunneling firms and firms with high financing restraint demonstrate significant effect of financing advantage, which further testifies both theoretical explanations for the creation of pyramidal structure. Conclusions of these studies have not only enriched and supplemented relevant studies on the root causes for the creation of pyramidal structure by Chinese private business groups, but provide practical support for firms to make correct and effective use of pyramidal structure as well.展开更多
In this paper,from the authority,decision-making body,supervisory body and implementing body,we analyze the governance structure evaluation indicators of farmers' specialized cooperatives,using objective and subje...In this paper,from the authority,decision-making body,supervisory body and implementing body,we analyze the governance structure evaluation indicators of farmers' specialized cooperatives,using objective and subjective combination weighting approach.And we draw the following conclusions:the rate of return of profits for membership,frequency of council convened and the number of members of board of supervisors have a great impact on the governance structure of cooperatives; the insider control phenomenon in cooperatives is more serious and the level of incentives is limited.Finally we put forward corresponding policy recommendations.展开更多
On the basis of questionnaire survey results of 100 agricultural cooperative economic organizations in Three Gorges Reservoir Area,this article uses the structural equation modeling as analysis tool to conduct empiric...On the basis of questionnaire survey results of 100 agricultural cooperative economic organizations in Three Gorges Reservoir Area,this article uses the structural equation modeling as analysis tool to conduct empirical analysis of the governance structure and performance of agricultural cooperative economic organizations. The results show that the ownership structure has the most critical impact on the performance of cooperative organizations,and the impact coefficient is as high as 0.92; the importance of oversight mechanism is basically equivalent to that of the council structure for cooperative organizations,and the impact coefficient is 0.87 and 0.86,respectively,second only to the ownership structure; the size of members' quit capacity also has a very important impact on the performance of organizations,with impact coefficient of 0.74. Thus,the problems influencing the performance of organizations,in the current governance structure of agricultural cooperative economic organizations in Three Gorges Reservoir Area,are pointed out. Finally,corresponding countermeasures are put forward.展开更多
Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research ob...Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary structure.The results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption pattern.The dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality one.During the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing trend.The per capita food carbon emissions of residents in urban and rural showed an overall upward trend.The total food carbon emissions in urban increased significantly,while that in rural increased first and then decreased.The influence of beef and mutton on carbon emissions is the highest in dietary structure.Compared with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern.展开更多
At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is es...At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is established along with a model that does not consider SSI.Eight long-period earthquake waves and two ordinary earthquake waves are selected as inputs for the dynamic time history analysis of the structure.The results show that the seismic response of a mid-story isolated structure considering SSI in mountainous areas can be amplified when compared with a structure that does not consider SSI.The structure response under long-period earthquakes is larger than that of ordinary earthquakes.The structure response under far-field harmonic-like earthquakes is larger than that of near-fault pulse-type earthquakes.The structure response under near-fault pulse-type earthquakes is larger than that of far-field non-harmonic earthquakes.When subjected to long-period earthquakes,the displacement of the isolated bearings exceeded the limit value,which led to instability and overturning of the structure.The structure with dampers in the isolated story could adequately control the nonlinear response of the structure,effectively reduce the displacement of the isolated bearings,and provide a convenient,efficient and economic method not only for new construction but also to retrofit existing structures.展开更多
Optical multilayer thin film structures have been widely used in numerous photonic applications.However,existing inverse design methods have many drawbacks because they either fail to quickly adapt to different design...Optical multilayer thin film structures have been widely used in numerous photonic applications.However,existing inverse design methods have many drawbacks because they either fail to quickly adapt to different design targets,or are difficult to suit for different types of structures,e.g.,designing for different materials at each layer.These methods also cannot accommodate versatile design situations under different angles and polarizations.In addition,how to benefit practical fabrications and manufacturing has not been extensively considered yet.In this work,we introduce OptoGPT(Opto Generative Pretrained Transformer),a decoder-only transformer,to solve all these drawbacks and issues simultaneously.展开更多
There is a substantial significance to construct city green spaces for improvement of the city environment and ecological function. The conservation of city green space includes a sound plan of green space and the non...There is a substantial significance to construct city green spaces for improvement of the city environment and ecological function. The conservation of city green space includes a sound plan of green space and the non-statutory parks and green open space, which are open spaces of both public and private land to be greened, they both become the basis for constructing an ecological green network of great city environment. To manipulate cross-sectoral integration, the city greening practice performs effective implementation. The main objective of an approach is to perform the governance indices of green spaces by expert questionnaire and then draft the greening strategies for Taipei city to improve the green landscape and the quality of city environment. The research draws on the green infrastructure and green ecological network system, analyzes the green ecological resources and the characteristic and structure of city spaces in Taipei city, in the meanwhile, learns the domestic and international experiences of greening development. By means of city green space of activation transformation and program of action under greening performance, Taipei city promotes the green image and the quality of city environment and green city landscape.展开更多
The 19th National Congress of the Communist Party of China(CPC)put forward the proposal of establishing a social governance model based on collaboration,participation,and common interests,with the aim of developing ne...The 19th National Congress of the Communist Party of China(CPC)put forward the proposal of establishing a social governance model based on collaboration,participation,and common interests,with the aim of developing new approaches to social governance and further modernizing China’s social system and capacity for governance.As a structuralized social relation addressing diversified governance bodies,the model has consolidated the social governance innovations achieved since the 18th CPC National Congress.Focusing on three dimensions—"value,""structure"and"roadmap,"this paper tries to interpret the value connotations and defining features behind the model and explores its development roadmap.Such a social governance model is a response to political,social and public value appeals,and an adjustment to the order of governance bodies,resource allocations and the benefit distribution structure.Its construction is a systematic and long-term project,which should aim continuously at satisfying people’s ever-higher needs,perfecting laws and regulations,cultivating a pool of specialized organizations and talents,exerting the technology advantages of the Internet in governance,and promoting socialization,legalization,specialization and intellectualization in social development.展开更多
基金Under the auspices of the Key Research Base of Humanities and Social Sciences of the Ministry of Education of China(No.22JJD790029)。
文摘Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linkages,the importance of marine economic net-work research is beginning to emerge.The construction of the marine economic network in China’s coastal areas is necessary to change the flow of land and sea resources and optimize regional marine economic development.Employing data from headquarters and branches of sea-related A-share listed enterprises to construct the marine economic network in China,we use social network analysis(SNA)to discuss the characteristics of its evolution as of 2010,2015,and 2020 and its governance.The following results were obtained.1)In terms of topological characteristics,the scale of the marine economic network in China’s coastal areas has accelerated and expan-ded,and the connections have become increasingly close;thus,this development has complex network characteristics.2)In terms of spatial structure,the intensity of the connection fluctuates and does not form stable development support;the group structure gradually becomes clear,but the overall pattern is fragmented;there are spatial differences in marine economic agglomeration radiation;the radi-ation effect of the eastern marine economic circle is obvious;and the polarization effect of northern and southern marine economic circles is significant.On this basis,we construct a framework for the governance of a marine economic network with the market,the government,and industry as the three governing bodies.By clarifying the driving factors and building objectives of marine economic network construction,this study aims to foster the high-quality development of China’s marine economy.
基金financially supported by the National Natural Science Foundation of China(Nos.52425408 and 52304345)the Fundamental Research Funds for the Central Universities,China(No.2023CDJXY-016)the Postdoctoral Science Foundation of Chongqing(No.CSTB2023NSCQ-BHX0174)。
文摘Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this limitation.Unlike most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina ores.The results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO concentration.Fourier transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO substitution.Deconvolution of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents increased.Structural analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO substitution.However,bond strength is another important factor affecting the slag viscosity.The occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.
基金National Natural Science Foundation of China(32201491)Young Elite Scientists Sponsorship Program by CAST(2023QNRC001)The authors extend their appreciation to the Deanship of Scientific Research at Northern Border University,Arar,KSA for funding this research work through the project number“NBU-FPEJ-2024-1101-02”.
文摘Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and hierarchical.Due to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding materials.Despite concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding materials.In particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be valuable.The preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and analyzed.The composite methods and fillers of various biomass materials were reviewed.this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field.
基金supported in part by Award 2121063 from National Science Foundation(to YM)AG66986 from the National Institutes of Health(to MSW).
文摘γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface receptors.Mutations inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as well.However,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-secretase.In this review,we focus on recent studies of structural dynamic mechanisms ofγ-secretase.Different mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics simulations.While an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental findings.The approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-secretase.In addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is discussed.Finally,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations of theγ-secretase-substrate complexes.Comprehensive understanding of the functional mechanisms ofγ-secretase will greatly facilitate the rational design of effective drug molecules for treating familial Alzheimer’s disease and perhaps Alzheimer’s disease in general.
基金supported by the National Natural Science Foundation of China(22265021)the Aeronautical Science Foundation of China(2020Z056056003)Jiangxi Provincial Natural Science Foundation(20232BAB212004).
文摘Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)materials.However,the relationship between configuration and electromagnetic(EM)loss mechanism has remained elusive.Herein,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co-doped helical carbon nanotubes with ultrabroad EMWA capability.Theoretical calculation and EM simulation confirm that the orbital coupling and spin polarization of the Mn–N4–C configuration,along with cross polarization generated by the helical structure,endow the helical converters with enhanced EM loss.As a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 mm.Through precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm thickness.Furthermore,constructing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB m2.This innovative approach not only advances the understanding of metal–nonmetal co-doping but also realizes broadband EMWA,thus contributing to the development of EMWA mechanisms and applications.
基金The Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research and development(R D) alliances.Therefore,the first objective of this study is to investigate why there exist different organizational governance structures in managing R D alliances;the second objective of this study is to give strategic advice in choosing appropriate forms with respect to various characteristics of R D alliances.Through the theoretical lens that integrate both transaction cost economics(TCE) and the resource-based view(RBV),a model that focuses on six major factors is developed for determining governance structure choices,namely,technological uncertainty,cultural difference,asset specificity,technology complementarity,appropriability of the individual firm's know-how,and trust.An R D alliance with higher technological uncertainty,larger cultural differences,and greater concerns for protecting an individual's know-how is more likely to adopt non-integrated alliances as the governing structure.An R D alliance with a higher degree of asset-specificity,greater technology complementarity and greater trust among partnering organizations is more likely to adopt integrated alliances as the governing structure;an R D alliance in the face of lower technological uncertainty will tend to adopt integrated alliances.The more aligned the choice of the governance structure with its determinants,the better the R D alliance will perform,and vice versa.
基金supported by the National Social Science Fund of China (13AZD079)the Zhejiang Provincial Natural Science Foundation of China (LQ14G030041 and LZ12G03003)the National Natural Science Foundation of China (71333011 and 71273234)
文摘Food safety issues constitute an international topic discussed by many scholars. Although there is an extensive body of literature on comparisons of food safety control practices across different governance structures, these studies have been conducted mainly in terms of qualitative and descriptive analysis. In addition, little attention has been given to family farms. This study addresses the food safety control practices adopted by firms with different governance structures in China. Food safety control is expressed by the following aspects, i.e., pollution-free, green, organic, and/or geographical indication prod- ucts certification, establishment of production records, and pesticide residue testing. Three types of governance structures that engage in agricultural production are distinguished: farmer cooperatives, agricultural companies, and family farms. The food safety control practices of various governance structures are investigated based on a database that comprises 600 vegetable and fruit enterprises in Zhejiang, China. The results show that (1) pesticide residue testing is adopted by the most firms, followed by products certification, and production records are adopted by the fewest firms, and (2) agricul- tural companies adopt more food safety control practices than family farms, while farmer cooperatives adopt the fewest food safety control practices. Governance structure features of a cooperative in terms of ownership, decision-making, and income distribution are the main reasons for the low level of food safety control in the cooperative.
文摘The purpose of this research is to examine the impact of financial distress status and corporate governance structures on the level of voluntary disclosure. We apply six independent variables, including the firm's financial distress status and five components of corporate governance structures, such as board independence, audit committee independence, institutional ownership, board meeting frequency, and audit committee meeting frequency. This research is carried out by examining the annual reports of 114 non-financial firms listed at the Indonesian Stock Exchange over the period of 2009-2011. To test hypotheses, we undergo two different analyses, including independent samples t-test and Multiple Linear Regression. We find that: (1) The audit committee independence and the audit committee meeting frequency have significant positive impacts on the level of voluntary disclosure; (2) The financial distress status is negatively related to the level of disclosure at various levels of significance; and (3) All the independent variables are simultaneously related to voluntary disclosure.
文摘Corporate governance structure system, or corporate organization system, which is a management model and system on the basis that the investment and control are separate, is the rules of setting up and operating the corporate organizations which is specified in Company laws among counties around the world. This article introduces the five parts of corporate governance structure system and discuses the function.
文摘Facing with the enormous data scale of the civil aviation industry, the vital issue that enterprises must consider is how to manage and make use of data to play its value. In this study, the content of the governance of big data of civil aviation is analyzed and this paper put forward the specific governance of big data resources of civil aviation to provide relevant support of the governance of big data resources of civil aviation.
文摘Using the method of principal component analysis, the paper conducts a systematic study on the issue of how corporate governance influences capital structure. The study manifests the results that the proportion of circulation shares, the ability that other big shareholders contend with the first biggest shareholder, the proportion of corporation-owned shares, and the frequency of directorate meetings all have a positive relationship with the liability level. Meanwhile, the concentration degree of owners' equity, the proportion of state-owned shares, the phenomenon that one person serves as both chairman of directorate and general manager, and the intensity of competition in product market are all negatively related to the level of debt. Finally, the scale of directorate, the proportion of independent directors as well as the percentage of management-owned shares have no significant relationship with the capital structure. The statistic analysis also shows that the proportion of independent directors of some Chinese listed companies does not meet the regulation of the CSRC. In addition, the paper tests the impacts of corporate operating characteristics on capital structure.
文摘In this paper, 87 farmers' specialized cooperatives in Sichuan Province were investigated firstly, and then their governance structure was analyzed from the aspects of authority, decision-making mechanism, supervision mechanism and executive body based on the corporative governance structure in narrowest sense, finally corresponding policy suggestions for improving the governance structure of farmers' specialized cooperatives in Sichuan Province were put forward. It is concluded that human control is serious within farmers' specialized cooperatives; inner supervision is effective; council has great effects on governance structure; the cooperatives give limited incentive to managers.
文摘It is generally believed in academia that there are two theoretical explanations of tunneling and financing advantage for the creation of pyramidal structure. However, there is no definitive conclusion on which explanation holds sway. Based on non-equilibrium panel data of seven years between 2004 and 2010, this empirical study uses the product market competition variables of "inter-sector competition" and "intra-sector competition" and the hierarchy and complexity of pyramidal structure, examines the correlation between pyramidal structure of Chinese private manufacturing listed firms and product market competition and patterns of change, and reveals the major causes of pyramidal structure. Empirical result indicates that, for Chinese private manufacturing listed companies, there is a significant negative correlation between product market competition and the hierarchy and complexity of pyramidal structure, which indicates that the creation of pyramidal structure has a preference on tunneling by controlling shareholders. On the basis of further considerations on corporate tunneling and financing restraint categorization, high-tunneling firms and firms with low financing restraint demonstrate significant tunneling motivations; low-tunneling firms and firms with high financing restraint demonstrate significant effect of financing advantage, which further testifies both theoretical explanations for the creation of pyramidal structure. Conclusions of these studies have not only enriched and supplemented relevant studies on the root causes for the creation of pyramidal structure by Chinese private business groups, but provide practical support for firms to make correct and effective use of pyramidal structure as well.
文摘In this paper,from the authority,decision-making body,supervisory body and implementing body,we analyze the governance structure evaluation indicators of farmers' specialized cooperatives,using objective and subjective combination weighting approach.And we draw the following conclusions:the rate of return of profits for membership,frequency of council convened and the number of members of board of supervisors have a great impact on the governance structure of cooperatives; the insider control phenomenon in cooperatives is more serious and the level of incentives is limited.Finally we put forward corresponding policy recommendations.
文摘On the basis of questionnaire survey results of 100 agricultural cooperative economic organizations in Three Gorges Reservoir Area,this article uses the structural equation modeling as analysis tool to conduct empirical analysis of the governance structure and performance of agricultural cooperative economic organizations. The results show that the ownership structure has the most critical impact on the performance of cooperative organizations,and the impact coefficient is as high as 0.92; the importance of oversight mechanism is basically equivalent to that of the council structure for cooperative organizations,and the impact coefficient is 0.87 and 0.86,respectively,second only to the ownership structure; the size of members' quit capacity also has a very important impact on the performance of organizations,with impact coefficient of 0.74. Thus,the problems influencing the performance of organizations,in the current governance structure of agricultural cooperative economic organizations in Three Gorges Reservoir Area,are pointed out. Finally,corresponding countermeasures are put forward.
基金Under the auspices of National Natural Science Foundation of China(No.42171230)。
文摘Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary structure.The results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption pattern.The dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality one.During the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing trend.The per capita food carbon emissions of residents in urban and rural showed an overall upward trend.The total food carbon emissions in urban increased significantly,while that in rural increased first and then decreased.The influence of beef and mutton on carbon emissions is the highest in dietary structure.Compared with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern.
基金National Natural Science Fund of China under Nos.52168072 and 51808467High-level Talents Support Plan of Yunnan Province of China(2020)。
文摘At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is established along with a model that does not consider SSI.Eight long-period earthquake waves and two ordinary earthquake waves are selected as inputs for the dynamic time history analysis of the structure.The results show that the seismic response of a mid-story isolated structure considering SSI in mountainous areas can be amplified when compared with a structure that does not consider SSI.The structure response under long-period earthquakes is larger than that of ordinary earthquakes.The structure response under far-field harmonic-like earthquakes is larger than that of near-fault pulse-type earthquakes.The structure response under near-fault pulse-type earthquakes is larger than that of far-field non-harmonic earthquakes.When subjected to long-period earthquakes,the displacement of the isolated bearings exceeded the limit value,which led to instability and overturning of the structure.The structure with dampers in the isolated story could adequately control the nonlinear response of the structure,effectively reduce the displacement of the isolated bearings,and provide a convenient,efficient and economic method not only for new construction but also to retrofit existing structures.
基金the National Science Foundation(PFI-008513 and FET-2309403)for the support of this work.
文摘Optical multilayer thin film structures have been widely used in numerous photonic applications.However,existing inverse design methods have many drawbacks because they either fail to quickly adapt to different design targets,or are difficult to suit for different types of structures,e.g.,designing for different materials at each layer.These methods also cannot accommodate versatile design situations under different angles and polarizations.In addition,how to benefit practical fabrications and manufacturing has not been extensively considered yet.In this work,we introduce OptoGPT(Opto Generative Pretrained Transformer),a decoder-only transformer,to solve all these drawbacks and issues simultaneously.
文摘There is a substantial significance to construct city green spaces for improvement of the city environment and ecological function. The conservation of city green space includes a sound plan of green space and the non-statutory parks and green open space, which are open spaces of both public and private land to be greened, they both become the basis for constructing an ecological green network of great city environment. To manipulate cross-sectoral integration, the city greening practice performs effective implementation. The main objective of an approach is to perform the governance indices of green spaces by expert questionnaire and then draft the greening strategies for Taipei city to improve the green landscape and the quality of city environment. The research draws on the green infrastructure and green ecological network system, analyzes the green ecological resources and the characteristic and structure of city spaces in Taipei city, in the meanwhile, learns the domestic and international experiences of greening development. By means of city green space of activation transformation and program of action under greening performance, Taipei city promotes the green image and the quality of city environment and green city landscape.
基金a staged research result of "Studies on the Path of Local Governments to Orderly Promote the Classification and Development of Social Organizations,"a research program sponsored by the National Social Sciences Fund(17BSH107)
文摘The 19th National Congress of the Communist Party of China(CPC)put forward the proposal of establishing a social governance model based on collaboration,participation,and common interests,with the aim of developing new approaches to social governance and further modernizing China’s social system and capacity for governance.As a structuralized social relation addressing diversified governance bodies,the model has consolidated the social governance innovations achieved since the 18th CPC National Congress.Focusing on three dimensions—"value,""structure"and"roadmap,"this paper tries to interpret the value connotations and defining features behind the model and explores its development roadmap.Such a social governance model is a response to political,social and public value appeals,and an adjustment to the order of governance bodies,resource allocations and the benefit distribution structure.Its construction is a systematic and long-term project,which should aim continuously at satisfying people’s ever-higher needs,perfecting laws and regulations,cultivating a pool of specialized organizations and talents,exerting the technology advantages of the Internet in governance,and promoting socialization,legalization,specialization and intellectualization in social development.