Introduction Mandibular segmental defects result in significant cosmetic and functional deficiencies.Meanwhile,the reconstruction of both the contour and function of the mandible is a challenging task.At present,autol...Introduction Mandibular segmental defects result in significant cosmetic and functional deficiencies.Meanwhile,the reconstruction of both the contour and function of the mandible is a challenging task.At present,autologous vascularized fibula transplantation is the most common method to reconstruct a mandible with long-span defects[1].展开更多
The transfer of graphene from metallic substrates onto application-specific substrates is usually inevitable for the applications of high-quality graphene films derived from chemical vapour deposition(CVD)approaches.C...The transfer of graphene from metallic substrates onto application-specific substrates is usually inevitable for the applications of high-quality graphene films derived from chemical vapour deposition(CVD)approaches.Commonly used to support the graphene films during the transfer,the coating of the polymer would produce the surface contaminations and hinder the industrially compatible transfer.In this work,through the thermal imidization of polyamide acid(PAA)to polyimide(PI)and tuning of the concentration of dangling chains,we achieved the ultraclean and crack-free transfer of graphene wafers with high electronic quality.The resulting contamination-free and hydrophilic surface also enabled the observed improved cell viability in a biomedical applications.By avoiding aqueous etching or the usage of strong bases,our proposed transfer method is industrially compatible for batch transfer of graphene films towards the real applications.展开更多
A novel Fe/amine modified chitosan composite(Fe/N-CS) was facilely synthesized and showed higher affinity to both Zn(Ⅱ) and cefazolin(CEF) than its precursors.Synergistic co-adsorption of them by Fe/NCS was observed ...A novel Fe/amine modified chitosan composite(Fe/N-CS) was facilely synthesized and showed higher affinity to both Zn(Ⅱ) and cefazolin(CEF) than its precursors.Synergistic co-adsorption of them by Fe/NCS was observed in varied conditions.The adsorption amount maximally increased by 100.1% for Zn and68.2% for CEF in bi-solute systems.The initial adsorption rate of Zn(Ⅱ) also improved with CEF.The increasing temperature facilitated coadsorption.The results of the preloading tests,FTIR/XPS characterizations and DFT calculations suggested that(1) both polyamines and Fe sites participated in the adsorption of Zn(Ⅱ) and CEF,(2) Zn(Ⅱ) could serve as a new efficient site for CEF,forming [amineZn-CEF]/[FeOH-Zn-CEF] ternary complexes,and(3) the co-presence of CEF shielded the electrostatic repulsion between protonated amines and Zn(Ⅱ),contributing to the enhancement of Zn(Ⅱ) adsorption.Further,the ion strength exerted positive and negative influences on the adsorption of Zn(Ⅱ) and CEF,respectively.Additionally,CEF and Zn(Ⅱ) were successively recovered by 0.1 mol/L NaOH followed by2 mmol/L HCl.Fe/N-CS could be stably reused five times.The findings imply that Fe/N-CS is promising for the highly efficient co-removal of concurrent heavy metals and antibiotics.展开更多
Scientific and technological innovation policies play a critical role in the innovative development of high-technology industrial parks.However,it remains unclear how scientific and technological innovation policies i...Scientific and technological innovation policies play a critical role in the innovative development of high-technology industrial parks.However,it remains unclear how scientific and technological innovation policies impact the innovation efficiency of hightechnology industrial parks and what the impact pathways are.An in-depth investigation of this topic can give an insight into the inherent relation between the scientific and technological innovation policies and technological innovation.By conducting a theoretical analysis,this study empirically analyzed the impact of scientific and technological innovation policies on the innovation efficiency of high-technology industrial parks.The main research methods applied in this study were linear regression and qualitative comparative analysis(QCA).The results showed that the policy targets drove innovation efficiency in a relatively minor way.Among all policy tools,the demand-based policy tools had the most significant influence on innovation efficiency.The supply-based and environment-based policy tools had notable positive impacts during the lag periods of policies.The policy mix pathways for scientific and technological innovation policies that impact innovation efficiency come in four forms,namely,the targets-directed,demand-driven,supplydominated environment optimization,and environment-dominated comprehensive pathways.Therefore,this study put forward proposals on classifying and refining the scientific and technological innovation policies and optimizing the policy mix-driven models.展开更多
Chemical vapor deposition(CVD)-grown graphene films on Cu foils,exhibiting fine scalability and high quality,are still suffering from the adverse impact of surface contamination,i.e.,amorphous carbon.Despite the recen...Chemical vapor deposition(CVD)-grown graphene films on Cu foils,exhibiting fine scalability and high quality,are still suffering from the adverse impact of surface contamination,i.e.,amorphous carbon.Despite the recent successful preparation of superclean graphene through Cu-vapor-assisted reactions,the formation mechanism of amorphous carbon remains unclear,especially with regard to the functions of substrates.Herein,we have found that the crystallographic orientations of underlying metal substrates would determine the cleanness of graphene in such a way that slower diffusion of active carbon species on asformed graphene-Cu(100)surface is the key factor that suppresses the formation of contamination.The facile synthesis of clean graphene is achieved on the meter-sized Cu(100)that is transformed from the polycrystalline Cu foils.Furthermore,a clean surface of graphene on Cu(100)ensures the reduction of transfer-related polymer residues,and enhanced optical and electrical performance,which allows for versatile applications of graphene in biosensors,functioning as flexible transparent electrodes.This work would offer a promising material platform for the fundamental investigation and create new opportunities for the advanced applications of high-quality graphene films.展开更多
Chemical vapor deposition(CVD)has emerged as a promising approach for the controlled growth of graphene films with appealing scalability,controllability,and uniformity.However,the synthesis of high-quality graphene fi...Chemical vapor deposition(CVD)has emerged as a promising approach for the controlled growth of graphene films with appealing scalability,controllability,and uniformity.However,the synthesis of high-quality graphene films still suffers from low production capacity and high energy consumption in the conventional hot-wall CVD system.In contrast,owing to the different heating mode,cold-wall CVD(CW-CVD)system exhibits promising potential for the industrial-scale production,but the quality of as-received graphene remains inferior with limited domain size and high defect density.Herein,we demonstrated an efficient method for the batch synthesis of high-quality graphene films with millimeter-sized domains based on CW-CVD system.With reduced defect density and improved properties,the as-received graphene was proven to be promising candidate material for electronics and anti-corrosion application.This study provides a new insight into the quality improvement of graphene derived from CW-CVD system,and paves a new avenue for the industrial production of high-quality graphene films for potential commercial applications.展开更多
基金supported in part by grants from the Clinical Research for Crossing Item of Shandong University(No.2020SDUCRCB001)the Shandong Provincial Natural Science Foundation(No.ZR2020MH180)+1 种基金the Rongxiang Regeneration Medicine Fund of Shandong University(No.2019SDRX-11)the Science and Technology Development Plan of Jinan City(No.201805041)。
文摘Introduction Mandibular segmental defects result in significant cosmetic and functional deficiencies.Meanwhile,the reconstruction of both the contour and function of the mandible is a challenging task.At present,autologous vascularized fibula transplantation is the most common method to reconstruct a mandible with long-span defects[1].
基金supported by the National Natural Science Foundation of China(Nos.T2188101 and 52372038)the National Key Research and Development Program of China(No.2022YFA1204900)the China Postdoctoral Science Foundation(No.2023M740030).
文摘The transfer of graphene from metallic substrates onto application-specific substrates is usually inevitable for the applications of high-quality graphene films derived from chemical vapour deposition(CVD)approaches.Commonly used to support the graphene films during the transfer,the coating of the polymer would produce the surface contaminations and hinder the industrially compatible transfer.In this work,through the thermal imidization of polyamide acid(PAA)to polyimide(PI)and tuning of the concentration of dangling chains,we achieved the ultraclean and crack-free transfer of graphene wafers with high electronic quality.The resulting contamination-free and hydrophilic surface also enabled the observed improved cell viability in a biomedical applications.By avoiding aqueous etching or the usage of strong bases,our proposed transfer method is industrially compatible for batch transfer of graphene films towards the real applications.
基金supported by the National Natural Science Foundation of China(No.51708281)Natural Science Foundation of Jiangsu Province,China(No.BK20170647)State Key Laboratory of Pollution Control and Resource Reuse Open Funding Project(No. PCRRF18022)
文摘A novel Fe/amine modified chitosan composite(Fe/N-CS) was facilely synthesized and showed higher affinity to both Zn(Ⅱ) and cefazolin(CEF) than its precursors.Synergistic co-adsorption of them by Fe/NCS was observed in varied conditions.The adsorption amount maximally increased by 100.1% for Zn and68.2% for CEF in bi-solute systems.The initial adsorption rate of Zn(Ⅱ) also improved with CEF.The increasing temperature facilitated coadsorption.The results of the preloading tests,FTIR/XPS characterizations and DFT calculations suggested that(1) both polyamines and Fe sites participated in the adsorption of Zn(Ⅱ) and CEF,(2) Zn(Ⅱ) could serve as a new efficient site for CEF,forming [amineZn-CEF]/[FeOH-Zn-CEF] ternary complexes,and(3) the co-presence of CEF shielded the electrostatic repulsion between protonated amines and Zn(Ⅱ),contributing to the enhancement of Zn(Ⅱ) adsorption.Further,the ion strength exerted positive and negative influences on the adsorption of Zn(Ⅱ) and CEF,respectively.Additionally,CEF and Zn(Ⅱ) were successively recovered by 0.1 mol/L NaOH followed by2 mmol/L HCl.Fe/N-CS could be stably reused five times.The findings imply that Fe/N-CS is promising for the highly efficient co-removal of concurrent heavy metals and antibiotics.
基金This research was funded by the Fundamental Research Funds for the Central Universities(grant number SWU2109517,SWU2009510)Chongqing Social Science Planning Youth Project(grant number 2021NDQN47).
文摘Scientific and technological innovation policies play a critical role in the innovative development of high-technology industrial parks.However,it remains unclear how scientific and technological innovation policies impact the innovation efficiency of hightechnology industrial parks and what the impact pathways are.An in-depth investigation of this topic can give an insight into the inherent relation between the scientific and technological innovation policies and technological innovation.By conducting a theoretical analysis,this study empirically analyzed the impact of scientific and technological innovation policies on the innovation efficiency of high-technology industrial parks.The main research methods applied in this study were linear regression and qualitative comparative analysis(QCA).The results showed that the policy targets drove innovation efficiency in a relatively minor way.Among all policy tools,the demand-based policy tools had the most significant influence on innovation efficiency.The supply-based and environment-based policy tools had notable positive impacts during the lag periods of policies.The policy mix pathways for scientific and technological innovation policies that impact innovation efficiency come in four forms,namely,the targets-directed,demand-driven,supplydominated environment optimization,and environment-dominated comprehensive pathways.Therefore,this study put forward proposals on classifying and refining the scientific and technological innovation policies and optimizing the policy mix-driven models.
基金The authors thank Beijing National Laboratory for Molecular ScienceThis work was supported by Beijing National Laboratory for Molecular Sciences(No.BNLMS-CXTD-202001)+2 种基金This work was financially supported by the Beijing Municipal Science&Technology Commission(Nos.Z181100004818001 and Z201100008720005)the National Basic Research Program of China(No.2016YFA0200101)the National Natural Science Foundation of China(No.52072042).
文摘Chemical vapor deposition(CVD)-grown graphene films on Cu foils,exhibiting fine scalability and high quality,are still suffering from the adverse impact of surface contamination,i.e.,amorphous carbon.Despite the recent successful preparation of superclean graphene through Cu-vapor-assisted reactions,the formation mechanism of amorphous carbon remains unclear,especially with regard to the functions of substrates.Herein,we have found that the crystallographic orientations of underlying metal substrates would determine the cleanness of graphene in such a way that slower diffusion of active carbon species on asformed graphene-Cu(100)surface is the key factor that suppresses the formation of contamination.The facile synthesis of clean graphene is achieved on the meter-sized Cu(100)that is transformed from the polycrystalline Cu foils.Furthermore,a clean surface of graphene on Cu(100)ensures the reduction of transfer-related polymer residues,and enhanced optical and electrical performance,which allows for versatile applications of graphene in biosensors,functioning as flexible transparent electrodes.This work would offer a promising material platform for the fundamental investigation and create new opportunities for the advanced applications of high-quality graphene films.
基金financially supported by the National Natural Science Foundation of China(Nos.T2188101,21525310,and 52072042)the National Key R&D Program of China(No.2018YFA0703502)+1 种基金Beijing National Laboratory for Molecular Sciences(No.BNLMS-CXTD-202001)Beijing Municipal Science&Technology Commission(Nos.Z181100004818001,Z18110300480001,Z18110300480002,Z191100000819005,Z191100000819007,and Z201100008720005)。
文摘Chemical vapor deposition(CVD)has emerged as a promising approach for the controlled growth of graphene films with appealing scalability,controllability,and uniformity.However,the synthesis of high-quality graphene films still suffers from low production capacity and high energy consumption in the conventional hot-wall CVD system.In contrast,owing to the different heating mode,cold-wall CVD(CW-CVD)system exhibits promising potential for the industrial-scale production,but the quality of as-received graphene remains inferior with limited domain size and high defect density.Herein,we demonstrated an efficient method for the batch synthesis of high-quality graphene films with millimeter-sized domains based on CW-CVD system.With reduced defect density and improved properties,the as-received graphene was proven to be promising candidate material for electronics and anti-corrosion application.This study provides a new insight into the quality improvement of graphene derived from CW-CVD system,and paves a new avenue for the industrial production of high-quality graphene films for potential commercial applications.
