Efficient,stable,and noble‐metal‐free electrocatalysts for both the oxygen evolution reaction and the hydrogen evolution reaction are highly imperative for the realization of low‐cost commercial water‐splitting el...Efficient,stable,and noble‐metal‐free electrocatalysts for both the oxygen evolution reaction and the hydrogen evolution reaction are highly imperative for the realization of low‐cost commercial water‐splitting electrolyzers.Herein,a cost‐effective and ecofriendly strategy is reported to fabricate coral‐like FeNi(OH)x/Ni as a bifunctional electrocatalyst for overall water splitting in alkaline media.With the assistance of mild corrosion of Ni by Fe(NO3)3,in situ generated FeNi(OH)x nanosheets are intimately attached on metallic coral‐like Ni.Integration of these nanosheets with the electrodeposited coral‐like Ni skeleton and the supermacroporous Ni foam substrate forms a binder‐free hierarchical electrode,which is beneficial for exposing catalytic active sites,accelerating mass transport,and facilitating the release of gaseous species.In 1.0 mol L^-1 KOH solution,a symmetric electrolyzer constructed with FeNi(OH)x/Ni as both the anode and the cathode exhibits an excellent activity with an applied potential difference of 1.52 V at 10 mA cm^-2,which is superior to that of an asymmetric electrolyzer constructed with the state‐of‐the‐art RuO2‐PtC couple(applied potential difference of 1.55 V at 10 mA cm^-2).This work contributes a facile and reliable strategy for manufacturing affordable,practical,and promising water‐splitting devices.展开更多
Center for Culture Studies under the Chinese Academy of Social Science released the Cultural Blue Book recently, setting the theme of China＇s cultural industry development in 2014 as ＂setting new coordinates to seek...Center for Culture Studies under the Chinese Academy of Social Science released the Cultural Blue Book recently, setting the theme of China＇s cultural industry development in 2014 as ＂setting new coordinates to seek new development＂. As is pointed out in the blue paper, China＇s cultural industry development has entered the shifting gears phase since the third plenary session of the CPC Central Committee, with the development foundation and drive as shifted from government to market. The key to further development is how to release the dividend through transformation, upgrading and marketoriented reform.展开更多
Nonalcoholic fatty liver disease(NAFLD)is a serious threat to public health,but its underlying mechanism remains poorly understood.In screening important genes using Gene Importance Calculator(GIC)we developed previou...Nonalcoholic fatty liver disease(NAFLD)is a serious threat to public health,but its underlying mechanism remains poorly understood.In screening important genes using Gene Importance Calculator(GIC)we developed previously,ribosomal modification protein rimK-like family member A(RIMKLA)was predicted as one essential gene but its functions remained largely unknown.The current study determined the roles of RIMKLA in regulating glucose and lipid metabolism.RIMKLA expression was reduced in livers of human and mouse with NAFLD.Hepatic RIMKLA overexpression ameliorated steatosis and hyperglycemia in obese mice.Hepatocyte-specific RIMKLA knockout aggravated high-fat diet(HFD)-induced dysregulated glucose/lipid metabolism in mice.Mechanistically,RIMKLA is a new protein kinase that phosphorylates betaine-homocysteine S-methyltransferase 1(BHMT1)at threonine 45(Thr45)site.Upon phosphorylation at Thr45 and activation,BHMT1 eliminated homocysteine(Hcy)to inhibit the activity of transcription factor activator protein 1(AP1)and its induction on fatty acid synthase(FASn)and cluster of differentiation 36(CD36)gene transcriptions,concurrently repressing lipid synthesis and uptake in hepatocytes.Thr45 to alanine(T45A)mutation inactivated BHMT1 to abolish RIMKLA’s repression on Hcy level,AP1 activity,FASn/CD36 expressions,and lipid deposition.BHMT1 overexpression rescued the dysregulated lipid metabolism in RIMKLA-deficient hepatocytes.In summary,RIMKLA is a novel protein kinase that phosphorylates BHMT1 at Thr45 to repress lipid synthesis and uptake.Under obese condition,inhibition of RIMKLA impairs BHMT1 activity to promote hepatic lipid deposition.展开更多
Metal-nitrogen doped carbon catalysts(M-N/C) with abundantly accessible M-Nxsites, particularly single metal atom M-N/C(SAM-N/C), have been developed as a substitute for expensive Pt-based catalysts.These catalysts ar...Metal-nitrogen doped carbon catalysts(M-N/C) with abundantly accessible M-Nxsites, particularly single metal atom M-N/C(SAM-N/C), have been developed as a substitute for expensive Pt-based catalysts.These catalysts are used to increase the efficiency of otherwise sluggish oxygen reduction reactions(ORR) and hydrogen evolution reactions(HER). However, although the agglomerated metal nanoparticles are usually easy to form, they are very difficult to remove due to the protective surface-coating carbon layers, a factor that significantly hampers SAM-N/C fabrication. Herein, we report a one-step pyrolysis approach to successfully fabricate single cobalt atom Co-N/C(SACo-N/C) by using a Co2+-SCN-coordination compound as the metal precursor. Thanks to the decomposition of Co2+-SCN-compound at lower temperature than that of carbon layer deposition, Co-rich particles grow up to larger ones before carbon layers formation. Even though encapsulated by the carbon layers, it is difficult for the large Co-rich particle to be completely sealed. And thus, it makes the Co atoms possible to escape from incomplete carbon layer, to coordinate with nitrogen atoms, and to form SACo-N/C catalysts. This SACo-N/C exhibits excellent performances for both ORR(half-wave potential of 0.878 V) and HER(overpotential at 10 mA/cm2 of178 m V), and is thus a potential replacement for Pt-based catalysts. When SACo-N/C is integrated into a Zn-O2 battery, battery with high open-circuit voltage(1.536 V) has high peak power density(266 mW/cm2)and large gravimetric energy density(755 mA h/gZn) at current densities of 100 mA/cm2. Thus, we believe that this strategy may offer a new direction for the effective generation of SAM-N/C catalysts.展开更多
A mathematic model has been presented to predict the decarburization kinetics of grain-oriented silicon steel sheet in the gas mixture of N2–H2–H2O during annealing.This model is based on the carbon flux balance bet...A mathematic model has been presented to predict the decarburization kinetics of grain-oriented silicon steel sheet in the gas mixture of N2–H2–H2O during annealing.This model is based on the carbon flux balance between the oxidation reaction at the surface and the carbon diffusion inside the steel sheet.It can be numerically solved to quantify the influences of annealing temperature and atmosphere on decarburization kinetics when the boundary conditions are properly determined.In case that a humid gas mixture is employed during annealing,the most influential process parameter is temperature rather than compositions of the gas mixture,because the diffusion of carbon in ferrite is the rate-limiting step.Therefore,a higher temperature is required for the efficient decarburization of the thicker silicon steel sheet using the industrial continuous annealing production line.展开更多
This paper examines the effects of CFO narcissism on audit fees in China.Using the size of CFO signatures in annual audit reports to measure individual narcissism,we find that CFO narcissism is associated with higher ...This paper examines the effects of CFO narcissism on audit fees in China.Using the size of CFO signatures in annual audit reports to measure individual narcissism,we find that CFO narcissism is associated with higher audit fees.We find empirical evidence that CFO narcissism significantly increases the audit fees of listed companies,and this effect is stronger in state-owned enterprises.This paper also explores the mediating effects of financial information and the engagement of prestigious Big-4 and Big-10 firms.The results show that companies with narcissistic CFOs have lower quality financial information and prefer more prestigious firms,which leads to higher audit fees.This research highlights the importance of CFO narcissism in corporate performance and provides new evidence that will be useful for listed companies that plan to hire senior executives.展开更多
Health risks assessment due to exposure to organic contaminated soil at an oil refinery out of service is conducted in this study by integrating health risk methods of U.S. EPA （United States Environmental Protection...Health risks assessment due to exposure to organic contaminated soil at an oil refinery out of service is conducted in this study by integrating health risk methods of U.S. EPA （United States Environmental Protection Agency）, ASTM （American Society for Testing and Materials） and VROM （Ministry of Housing, Spatial Planning and the Environment in Netherlands）, with the localized parameters using Chinese demographic characteristics and site features. The monitoring results show that the concentration of benzene, benzo（a）pyrene and benzo（a）anthracene in the soil of the site all exceed their risk screening values, respectively, with pollutants concentrated in soil 0.1-5.5 m beneath the surface. To estimate health risks of the site with the 95% upper confidence limit of the pollution, we focus on three major exposure pathways, namely, oral ingestion, dermal contact and breath inhalation, which indicates carcinogenic risk （CR） and non-carcinogenic hazard quotient （HQ） of the contaminated soil reach 9.59×10^-5 and 15.46, respectively, exceeding the acceptable level of 10^5 and 1, posing severe health hazards to the residents at the site. KEY WORDS： contaminated site, health risk, soil, organic contamination.展开更多
Pelleting is the most extensively used thermal processing method in feed industry.In this article,a single pellet press device was developed to investigate the pelleting processing of animal feed.Effects of moisture c...Pelleting is the most extensively used thermal processing method in feed industry.In this article,a single pellet press device was developed to investigate the pelleting processing of animal feed.Effects of moisture content(10%-18%w.b.),preheating temperature(60°C-100°C)and maximum compression force(0.2-0.6 kN)on feed pellet were determined and analyzed,as well as energy consumption.The results showed that unit density,pellet hardness and energy consumption were 0.87-2.92 g/cm3,1.08-4.55 kg,and 3.27-12.66 J/g,respectively.Unit density was found to increase with the increase of preheating temperature and maximum compression force,but decrease with the increase of moisture content.Pellet hardness showed a first ascending then descending trend with the increase of moisture content,but exhibited a positive relationship with both preheating temperature and maximum compression force.Energy consumption increased with the increase of maximum compression force,but exhibited descending trends with the increase of moisture content and preheating temperature.Due to its features of low cost,high efficiency and easy control,the single pellet press device has a wide application prospect in feed processing.展开更多
文摘Efficient,stable,and noble‐metal‐free electrocatalysts for both the oxygen evolution reaction and the hydrogen evolution reaction are highly imperative for the realization of low‐cost commercial water‐splitting electrolyzers.Herein,a cost‐effective and ecofriendly strategy is reported to fabricate coral‐like FeNi(OH)x/Ni as a bifunctional electrocatalyst for overall water splitting in alkaline media.With the assistance of mild corrosion of Ni by Fe(NO3)3,in situ generated FeNi(OH)x nanosheets are intimately attached on metallic coral‐like Ni.Integration of these nanosheets with the electrodeposited coral‐like Ni skeleton and the supermacroporous Ni foam substrate forms a binder‐free hierarchical electrode,which is beneficial for exposing catalytic active sites,accelerating mass transport,and facilitating the release of gaseous species.In 1.0 mol L^-1 KOH solution,a symmetric electrolyzer constructed with FeNi(OH)x/Ni as both the anode and the cathode exhibits an excellent activity with an applied potential difference of 1.52 V at 10 mA cm^-2,which is superior to that of an asymmetric electrolyzer constructed with the state‐of‐the‐art RuO2‐PtC couple(applied potential difference of 1.55 V at 10 mA cm^-2).This work contributes a facile and reliable strategy for manufacturing affordable,practical,and promising water‐splitting devices.
文摘Center for Culture Studies under the Chinese Academy of Social Science released the Cultural Blue Book recently, setting the theme of China＇s cultural industry development in 2014 as ＂setting new coordinates to seek new development＂. As is pointed out in the blue paper, China＇s cultural industry development has entered the shifting gears phase since the third plenary session of the CPC Central Committee, with the development foundation and drive as shifted from government to market. The key to further development is how to release the dividend through transformation, upgrading and marketoriented reform.
基金supported by National Natural Science Foundation of China(82300957/82230024/82025008/82070844)Beijing Natural Science Foundation(7212123).
文摘Nonalcoholic fatty liver disease(NAFLD)is a serious threat to public health,but its underlying mechanism remains poorly understood.In screening important genes using Gene Importance Calculator(GIC)we developed previously,ribosomal modification protein rimK-like family member A(RIMKLA)was predicted as one essential gene but its functions remained largely unknown.The current study determined the roles of RIMKLA in regulating glucose and lipid metabolism.RIMKLA expression was reduced in livers of human and mouse with NAFLD.Hepatic RIMKLA overexpression ameliorated steatosis and hyperglycemia in obese mice.Hepatocyte-specific RIMKLA knockout aggravated high-fat diet(HFD)-induced dysregulated glucose/lipid metabolism in mice.Mechanistically,RIMKLA is a new protein kinase that phosphorylates betaine-homocysteine S-methyltransferase 1(BHMT1)at threonine 45(Thr45)site.Upon phosphorylation at Thr45 and activation,BHMT1 eliminated homocysteine(Hcy)to inhibit the activity of transcription factor activator protein 1(AP1)and its induction on fatty acid synthase(FASn)and cluster of differentiation 36(CD36)gene transcriptions,concurrently repressing lipid synthesis and uptake in hepatocytes.Thr45 to alanine(T45A)mutation inactivated BHMT1 to abolish RIMKLA’s repression on Hcy level,AP1 activity,FASn/CD36 expressions,and lipid deposition.BHMT1 overexpression rescued the dysregulated lipid metabolism in RIMKLA-deficient hepatocytes.In summary,RIMKLA is a novel protein kinase that phosphorylates BHMT1 at Thr45 to repress lipid synthesis and uptake.Under obese condition,inhibition of RIMKLA impairs BHMT1 activity to promote hepatic lipid deposition.
基金supported by the National Key Research and Development Program of China(2016YFB0101202)the National Natural Science Foundation of China(21761162015,91534205,21436003)the Fundamental Research Funds for the Central Universities
文摘Metal-nitrogen doped carbon catalysts(M-N/C) with abundantly accessible M-Nxsites, particularly single metal atom M-N/C(SAM-N/C), have been developed as a substitute for expensive Pt-based catalysts.These catalysts are used to increase the efficiency of otherwise sluggish oxygen reduction reactions(ORR) and hydrogen evolution reactions(HER). However, although the agglomerated metal nanoparticles are usually easy to form, they are very difficult to remove due to the protective surface-coating carbon layers, a factor that significantly hampers SAM-N/C fabrication. Herein, we report a one-step pyrolysis approach to successfully fabricate single cobalt atom Co-N/C(SACo-N/C) by using a Co2+-SCN-coordination compound as the metal precursor. Thanks to the decomposition of Co2+-SCN-compound at lower temperature than that of carbon layer deposition, Co-rich particles grow up to larger ones before carbon layers formation. Even though encapsulated by the carbon layers, it is difficult for the large Co-rich particle to be completely sealed. And thus, it makes the Co atoms possible to escape from incomplete carbon layer, to coordinate with nitrogen atoms, and to form SACo-N/C catalysts. This SACo-N/C exhibits excellent performances for both ORR(half-wave potential of 0.878 V) and HER(overpotential at 10 mA/cm2 of178 m V), and is thus a potential replacement for Pt-based catalysts. When SACo-N/C is integrated into a Zn-O2 battery, battery with high open-circuit voltage(1.536 V) has high peak power density(266 mW/cm2)and large gravimetric energy density(755 mA h/gZn) at current densities of 100 mA/cm2. Thus, we believe that this strategy may offer a new direction for the effective generation of SAM-N/C catalysts.
文摘A mathematic model has been presented to predict the decarburization kinetics of grain-oriented silicon steel sheet in the gas mixture of N2–H2–H2O during annealing.This model is based on the carbon flux balance between the oxidation reaction at the surface and the carbon diffusion inside the steel sheet.It can be numerically solved to quantify the influences of annealing temperature and atmosphere on decarburization kinetics when the boundary conditions are properly determined.In case that a humid gas mixture is employed during annealing,the most influential process parameter is temperature rather than compositions of the gas mixture,because the diffusion of carbon in ferrite is the rate-limiting step.Therefore,a higher temperature is required for the efficient decarburization of the thicker silicon steel sheet using the industrial continuous annealing production line.
文摘This paper examines the effects of CFO narcissism on audit fees in China.Using the size of CFO signatures in annual audit reports to measure individual narcissism,we find that CFO narcissism is associated with higher audit fees.We find empirical evidence that CFO narcissism significantly increases the audit fees of listed companies,and this effect is stronger in state-owned enterprises.This paper also explores the mediating effects of financial information and the engagement of prestigious Big-4 and Big-10 firms.The results show that companies with narcissistic CFOs have lower quality financial information and prefer more prestigious firms,which leads to higher audit fees.This research highlights the importance of CFO narcissism in corporate performance and provides new evidence that will be useful for listed companies that plan to hire senior executives.
基金supported by Three Gold City Real Estate Development Co. LTD.,Wuhan (No. 2009046268)
文摘Health risks assessment due to exposure to organic contaminated soil at an oil refinery out of service is conducted in this study by integrating health risk methods of U.S. EPA （United States Environmental Protection Agency）, ASTM （American Society for Testing and Materials） and VROM （Ministry of Housing, Spatial Planning and the Environment in Netherlands）, with the localized parameters using Chinese demographic characteristics and site features. The monitoring results show that the concentration of benzene, benzo（a）pyrene and benzo（a）anthracene in the soil of the site all exceed their risk screening values, respectively, with pollutants concentrated in soil 0.1-5.5 m beneath the surface. To estimate health risks of the site with the 95% upper confidence limit of the pollution, we focus on three major exposure pathways, namely, oral ingestion, dermal contact and breath inhalation, which indicates carcinogenic risk （CR） and non-carcinogenic hazard quotient （HQ） of the contaminated soil reach 9.59×10^-5 and 15.46, respectively, exceeding the acceptable level of 10^5 and 1, posing severe health hazards to the residents at the site. KEY WORDS： contaminated site, health risk, soil, organic contamination.
基金The authors acknowledge that this work was financially supported by the National Natural Science Foundation of China(Grant No.52005012)the Key Laboratory of Environment Controlled Aquaculture(Dalian Ocean University)Ministry of Education(Grant No.202222).
文摘Pelleting is the most extensively used thermal processing method in feed industry.In this article,a single pellet press device was developed to investigate the pelleting processing of animal feed.Effects of moisture content(10%-18%w.b.),preheating temperature(60°C-100°C)and maximum compression force(0.2-0.6 kN)on feed pellet were determined and analyzed,as well as energy consumption.The results showed that unit density,pellet hardness and energy consumption were 0.87-2.92 g/cm3,1.08-4.55 kg,and 3.27-12.66 J/g,respectively.Unit density was found to increase with the increase of preheating temperature and maximum compression force,but decrease with the increase of moisture content.Pellet hardness showed a first ascending then descending trend with the increase of moisture content,but exhibited a positive relationship with both preheating temperature and maximum compression force.Energy consumption increased with the increase of maximum compression force,but exhibited descending trends with the increase of moisture content and preheating temperature.Due to its features of low cost,high efficiency and easy control,the single pellet press device has a wide application prospect in feed processing.
