In semiconductor photocatalysts,the easy recombination of photogenerated carriers seriously affects the application of photocatalytic materials in water treatment.To solve the serious problem of electron−hole pair rec...In semiconductor photocatalysts,the easy recombination of photogenerated carriers seriously affects the application of photocatalytic materials in water treatment.To solve the serious problem of electron−hole pair recombination in perylene diimide(PDI)organic semiconductors,we loaded ferric hydroxyl oxide(FeOOH)on PDI materials,successfully prepared novel FeOOH@PDI photocatalytic materials,and constructed a photo-Fenton system.The system was able to achieve highly efficient degradation of BPA under visible light,with a degradation rate of 0.112 min^(−1)that was 20 times higher than the PDI system,and it also showed universal degradation performances for a variety of emerging organic pollutants and anti-interference ability.The mechanism research revealed that the FeOOH has the electron trapping property,which can capture the photogenerated electrons on the surface of PDI,effectively reducing the compounding rate of photogenerated carriers of PDI and accelerating the iron cycling and H2O2 activation on the surface of FeOOH at the same time.This work provides new insights and methods for solving the problem of easy recombination of carriers in semiconductor photocatalysts and degrading emerging organic pollutants.展开更多
In the presence of dynamic organizational environment and a growing supply of‘knowledgeable employees’which require more professional managers to address their fast changing and increasing needs,senior and middle le...In the presence of dynamic organizational environment and a growing supply of‘knowledgeable employees’which require more professional managers to address their fast changing and increasing needs,senior and middle level managers are now required to keep up with the dynamic and learning environment more than ever.In order to train senior and middle level managers,the article has recommended four perspectives to encourage the development of learning manager.The first aspect for senior and middle level mangers is to integrate learning talents into their practices.The second point is to encourage managers to provide strong support for individuals and teams to develop a learning organization.The third point encourages learning managers and organizations to be composed into the culture of the organization.The last point advocates for more open and free dissemination of information and knowledge to be allowed within an organization.展开更多
Energy sustainable development has stimulated the pursuit of an eco-friendly energy storage system.Carbon peak and neutrality targets oriented energy storage development will guide the way of further studies on batter...Energy sustainable development has stimulated the pursuit of an eco-friendly energy storage system.Carbon peak and neutrality targets oriented energy storage development will guide the way of further studies on batteries system.However,conventional batteries system(lead-acid batteries,lithium-ion batteries)based on ungreen transition metal oxide,flammable electrolytes or hazardous metals cannot keep pace with the development of society sooner or later.Thus,vast explorations on the advanced rechargeable battery systems were conducted.Compared with other battery systems,zinc ion battery systems with inherent safety,low cost were widely investigated.Especially,the zinc organic batteries based on the eco-efficiency organic cathodes were promising alternative advanced batteries for future energy storage systems.Therefore,various organics and different electrochemistry mechanisms were explored in the zinc batteries system.Herein,a timely review on elaborate analysis about functional groups,fundamentals,progress accompanied by the discussion on the four core issues:voltage,capacity,rate performance,cycle life was presented.Specifically,aiming at these issues,three levels of solution strategies:materials design concepts,morphology structure optimization and electrolyte environment were summarized and proposed for the development and innovation of zinc organic batteries.展开更多
Deep-level defects and random oriented configuration in perovskite crystallization process would cause the nonradiative recombination and further affect the performance of perovskite solar cells(PSCs).Herein,two metal...Deep-level defects and random oriented configuration in perovskite crystallization process would cause the nonradiative recombination and further affect the performance of perovskite solar cells(PSCs).Herein,two metal-organic frameworks(MOFs)with tunable Lewis-base passivation sites have been constructed(Cd-Httb and Cd-Httb-BDC,Httb=5-(4-(1H-1,2,4-triazole-1-yl)benzyl)-1h-tetrazole,BDC=1,4-dicarboxybenzene)to eliminate deep-level defects and simultaneously as nanostructured heterogeneous nucleation seed to assist the growth of large-grained perovskite films.Compared with the control and Cd-Httb,Cd-Httb-BDC designed with mix-ligands strategy exhibited the enhanced inducted effect on the crystallization and nucleation of high-quality perovskite films during annealing process.Consequently,the resultant Cd-Httb-BDC-modified device achieved higher power conversion efficiency(PCE)(22.18%)than the control(20.89%)and Cd-Httb(21.56%).Meanwhile,the unencapsulated Cd-Httb-BDC-modified device still maintained 90%of initial PCE after 1500 h in ambient conditions and exhibited enhanced thermal stability(85℃ in N_(2) atmosphere).This work presented a successful example of mixligands strategy on construction of high-quality MOF-assisted perovskite films for high-efficient and stable PSCs.展开更多
Covalent organic frameworks(COFs), as an emerging class of porous crystalline materials constructed by covalent links between the building monomers, have gained tremendous attention. Over the past 15 years, COFs have ...Covalent organic frameworks(COFs), as an emerging class of porous crystalline materials constructed by covalent links between the building monomers, have gained tremendous attention. Over the past 15 years, COFs have made rapid progress and substantial development in the chemistry and materials fields. However, the synthesis of COFs has been dominated by solvothermal methods for a long time and it usually involves high temperature, high pressure and toxic organic solvents, which created many challenges for environmental considerations. Recently,the exploration of new approaches for facile fabrication of COFs has aroused extensive interest. Hence, in this review, we comprehensively describe the synthetic strategies of COFs from the aspects of nonconventional heating methods and reaction media. In addition, the advantages,limitations and properties of the preparation methods are compared. Finally, we outline the main challenges and development prospects of the synthesis of COFs in the future and propose some possible solutions.展开更多
Organic fi eld-eff ect transistors(OFETs)are fabricated using organic semiconductors(OSCs)as the active layer in the form of thin fi lms.Due to its advantages of high sensitivity,low cost,compact integration,fl exibil...Organic fi eld-eff ect transistors(OFETs)are fabricated using organic semiconductors(OSCs)as the active layer in the form of thin fi lms.Due to its advantages of high sensitivity,low cost,compact integration,fl exibility,and printability,OFETs have been used extensively in the sensing area.For analysis platforms,the construction of sensing layers is a key element for their effi cient detection capability.The strategy used to immobilize biomolecules in these devices is especially important for ensuring that the sensing functions of the OFET are eff ective.Generally,analysis platforms are developed by modifying the gate/electrolyte or OSC/electrolyte interface using biomolecules,such as enzymes,antibodies,or deoxyribonucleic acid(DNA)to ensure high selectivity.To provide better or more convenient biological immobilization methods for researchers in this fi eld and thereby improve detection sensitivity,this review summarizes recent developments in the immobilization strategies used for biological macromolecules in OFETs,including cross-linking,physical adsorption,embedding,and chemical covalent binding.The infl uences of biomolecules on device performance are also discussed.展开更多
This paper sets to explore management perceptions regarding the impact of operational process factors on strategy implementation in microfinance organisations in Kenya.Small and medium enterprises(SMEs)play a critical...This paper sets to explore management perceptions regarding the impact of operational process factors on strategy implementation in microfinance organisations in Kenya.Small and medium enterprises(SMEs)play a critical role in developing countries as a source of employment creation and a basis for industrialization.However,the sector receives inadequate financial support from commercial banks as it is considered to bear high risks and operational costs associate with lending small loan amounts.Microfinance organisations(MFOs)that serve this sector will need to expand their operations to increase their outreach to SMEs.Formulation and implementation of competitive strategies will enable MFOs to achieve growth and sustainability.Content,context and operational process factors appear to have a significance positive relationship to the level of strategy implementation.This paper is focusing on operational process factors impacting on strategy implementation and is part of a full study on the topic of strategy implementation in MFOs.Comprehensive literature review provided the theoretical framework for the study.Primary data were collected by means of a survey obtaining 300 self-administered questionnaires from managers in 135 MFOs in Kenya.The study revealed that the level of strategy implementation in MFOs in Kenya is moderate to high.This study has revealed that the operational process category of factors is more significant to the level of strategy implementation than content and context factors.Five operational process factors critical to strategy implementation include:operational planning and monitoring,management control systems,people-strategy fit,teamwork,and effective communication.Further,the level of strategy implementation has significance positive influence to MFOs’financial sustainability and outreach.Practical guidelines are provided to assist MFOs in developing countries to improve the level of strategy implementation by focusing on operational process factors.展开更多
"Advance organizer"is a practical teaching strategy proposed by American modern educational psychologist Ausubel in 1960.This research considers learners'use of metacognitive strategy in the teaching act..."Advance organizer"is a practical teaching strategy proposed by American modern educational psychologist Ausubel in 1960.This research considers learners'use of metacognitive strategy in the teaching activities of"advance organizer",trying to explore the effects of metacognitive strategy in the"advance organizer"teaching practices and testing whether"advance organizer"can effectively help students understand and retain reading materials.Further researches should be focused on how to conduct learners'"metacognitive strategy"training and employ learners'metacognitive strategies into"advance organizer"teaching activities.展开更多
Solid organ transplant recipients face unique challenges in managing their im-munosuppressed status,making vaccination a critical consideration.This review aimed to comprehensively analyze current recommendations,eval...Solid organ transplant recipients face unique challenges in managing their im-munosuppressed status,making vaccination a critical consideration.This review aimed to comprehensively analyze current recommendations,evaluate the effi-cacy of vaccinations in this population,and assess safety concerns.We explored the latest evidence on vaccine types,timing,and potential benefits for transplant patients,highlighting the importance of individualized approaches for routinely used vaccines as well as coronavirus disease 2019 vaccines.By synthesizing avai-lable data,this review underscored the pressing need to optimize vaccination strategies,ensuring that transplant recipients can obtain the full protection against many pathogens while minimizing risks associated with their post-transplant immunosuppression.展开更多
Nanoscale hierarchically porous metal–organic frameworks(NHP-MOFs)have received unprecedented attention in many fields owing to their integration of the strengths of nanoscale size(<1μm)and hierarchical porous st...Nanoscale hierarchically porous metal–organic frameworks(NHP-MOFs)have received unprecedented attention in many fields owing to their integration of the strengths of nanoscale size(<1μm)and hierarchical porous structure(micro-,meso-and/or macro-pores)of MOFs.This review focuses on recent advances in the main synthetic strategies for NHP-MOFs based on different metal ions(e.g.,Cu,Fe,Co,Zn,Al,Zr,and Cr),including the template method,composite technology,post-synthetic modification,in situ growth and the grind method.In addition,the mechanisms of synthesis,regulation techniques and the advantages and disadvantages of various methods are discussed.Finally,the challenges and prospects of the commercialisation of promising NHP-MOFs are also presented.The purpose of this review is to provide a road map for future design and development of NHP-MOFs for practical application.展开更多
Small molecule organic photovoltaics(SMPVs) were prepared by utilizing liquid crystalline donor material BTR-Cl and two similar optical bandgap non-fullerene acceptor materials BTP-BO-4 F and Y6.The BTPBO-4 F and Y6 h...Small molecule organic photovoltaics(SMPVs) were prepared by utilizing liquid crystalline donor material BTR-Cl and two similar optical bandgap non-fullerene acceptor materials BTP-BO-4 F and Y6.The BTPBO-4 F and Y6 have the similar optical bandgap and different absorption coefficients.The corresponding binary SMPVs exhibit different short circuit current density(/sc)(20.38 vs.23.24 mA cm^(-2)),and fill factor(FF)(70.77% vs.67.21%).A 14.46% power conversion efficiency(PCE) is acquired in ternary SMPVs with 30 wt% Y6,companied with a JSC of 24.17 mA cm^(-2) a FF of 68.78% and an open circuit voltage(Voc) of 0.87 V.The improvement on PCE of ternary SMPVs should originate from the well trade-off between phase separation and photon harvesting of ternary active layers by incorporating 30 wt% Y6 in acceptors.This work may deliver insight onto the improved performance of SMPVs by superposing the superiorities of binary SMPVs with similar optical bandgap acceptors into one ternary cell.展开更多
Organic solar cells(OSCs)have received great attention for the prominent advantage of low-cost,light-weight and potential for fabricating flexible and semi-transparent device via roll-to-roll printing toward making be...Organic solar cells(OSCs)have received great attention for the prominent advantage of low-cost,light-weight and potential for fabricating flexible and semi-transparent device via roll-to-roll printing toward making better use of inexhaustible renewable clean energy during the past years[1-4].展开更多
The development of efficient and cost‐effective metal‐free electrocatalysts for oxygen reduction reaction(ORR)has become crucial for electrochemical energy systems.However,reasonably validating and precisely regulat...The development of efficient and cost‐effective metal‐free electrocatalysts for oxygen reduction reaction(ORR)has become crucial for electrochemical energy systems.However,reasonably validating and precisely regulating the active sites for designing optimized materials are still challenging.Herein,we report a precise and controllable tandem strategy to boost the ORR activity based on metal‐free covalent organic frameworks(MFCOFs)comprising imine‐N,thiophene‐S,or triazine‐N.Among these MFCOFs,post‐tandem BTT‐TAT‐COF structure displayed a more positive catalytic capability and excellent electrochemical stability,indicating that the synergistic catalysis of multiple active sites induced the ORR catalytic activity through the conjugated skeleton of the structure.Density‐functional theory calculations suggest that the series‐connected backbone contained highly effective electrocatalytic active centers and provided synergistic catalysis.More importantly,this strategy highlights new opportunities for the advancement of efficient COF‐based metal‐free ORR catalysts.展开更多
Sunken yaodongs, or sunken yaodong houses, in Guanzhong are typical representatives of traditional Chinese dwellings. This paper analyzed the characteristics and existing problems of yaodongs, and put forward the idea...Sunken yaodongs, or sunken yaodong houses, in Guanzhong are typical representatives of traditional Chinese dwellings. This paper analyzed the characteristics and existing problems of yaodongs, and put forward the idea of the organic renewal of sunken yaodongs with Dengjiapo Village in Yongshou County, Xianyang, Shaanxi as the research object.展开更多
The present study investigated the impact from GOs (Graphic Organizers) upon reading comprehension ability. To this end, an OPT (Oxford Placement Test) was administered to a research population (N = 354) in orde...The present study investigated the impact from GOs (Graphic Organizers) upon reading comprehension ability. To this end, an OPT (Oxford Placement Test) was administered to a research population (N = 354) in order to homogenize it. On the basis of the test results, the population was sorted into three groups of reading-low, reading-mid, and reading-high students. Sixty participants with the lowest level of reading comprehension proficiency were randomly selected and assigned to an EG (Experimental Group) (N = 30) and a CG (Control Group) (N = 30). Afterwards, a TOEFL (Test of English as a Foreign Language) reading comprehension pretest was administered to both groups in order to determine their current level of reading proficiency. Then, the EG received 10 successive 90-minute sessions on GOs as post-reading strategies for expository text comprehension, while the CG received the same amount of treatment on other post-reading strategies. In the end, another TOEFL reading comprehension posttest was administered to the research groups to measure their reading comprehension performance level after the treatment. The results revealed that GOs were statistically more significant and effective for the low-skilled readers than other post-reading strategies.展开更多
This paper argues for the adoption of concept attainment strategy when teaching math and shows the structure of this curriculum design that can substantially improve math instruction and comprehension in K-12 educatio...This paper argues for the adoption of concept attainment strategy when teaching math and shows the structure of this curriculum design that can substantially improve math instruction and comprehension in K-12 education.Initial findings based on informal surveys of teacher candidates indicate many of them do not have a clear understanding of the concepts they are expected to teach.The concept attainment strategy is a proven effective method used in social studies for teaching powerful concepts like democracy and liberty.One reason for many students feeling inadequate about their math skills stem from their lack of understanding of the key math concepts like area,perimeter,percent,and others.Poor understanding of the math fundamentals in early grades if not rectified,develops into a dislike for an incomprehensible subject.The concept attainment strategy is an inductive approach that allows the students to participate in knowledge construction and master the fundamental math skills.This paper shows how the structure of this social studies curriculum design can be adapted for teaching mathematics and invites practitioners and scholars to consider this approach to improve math instruction.展开更多
基金supported by the National Natural Science Foundation of China(No.22306178 and 22176155)Outstanding Youth Talents of Sichuan Science and Technology Program(No.22JCQN0061)+1 种基金National Natural Science Foundation of China(No.22306012)Guangdong Basic and Applied Basic Research Foundation(No.2022A1515110578).
文摘In semiconductor photocatalysts,the easy recombination of photogenerated carriers seriously affects the application of photocatalytic materials in water treatment.To solve the serious problem of electron−hole pair recombination in perylene diimide(PDI)organic semiconductors,we loaded ferric hydroxyl oxide(FeOOH)on PDI materials,successfully prepared novel FeOOH@PDI photocatalytic materials,and constructed a photo-Fenton system.The system was able to achieve highly efficient degradation of BPA under visible light,with a degradation rate of 0.112 min^(−1)that was 20 times higher than the PDI system,and it also showed universal degradation performances for a variety of emerging organic pollutants and anti-interference ability.The mechanism research revealed that the FeOOH has the electron trapping property,which can capture the photogenerated electrons on the surface of PDI,effectively reducing the compounding rate of photogenerated carriers of PDI and accelerating the iron cycling and H2O2 activation on the surface of FeOOH at the same time.This work provides new insights and methods for solving the problem of easy recombination of carriers in semiconductor photocatalysts and degrading emerging organic pollutants.
文摘In the presence of dynamic organizational environment and a growing supply of‘knowledgeable employees’which require more professional managers to address their fast changing and increasing needs,senior and middle level managers are now required to keep up with the dynamic and learning environment more than ever.In order to train senior and middle level managers,the article has recommended four perspectives to encourage the development of learning manager.The first aspect for senior and middle level mangers is to integrate learning talents into their practices.The second point is to encourage managers to provide strong support for individuals and teams to develop a learning organization.The third point encourages learning managers and organizations to be composed into the culture of the organization.The last point advocates for more open and free dissemination of information and knowledge to be allowed within an organization.
基金supported by the National Natural Science Foundation of China(Nos.51771094 and 21835004)the National Key R&D Program of China(No.2016YFB0901500)+1 种基金Ministry of Education of China(Nos.B12015 and IRT13R30)the Tianjin Natural Science Foundation(No.18JCZDJC31500)。
文摘Energy sustainable development has stimulated the pursuit of an eco-friendly energy storage system.Carbon peak and neutrality targets oriented energy storage development will guide the way of further studies on batteries system.However,conventional batteries system(lead-acid batteries,lithium-ion batteries)based on ungreen transition metal oxide,flammable electrolytes or hazardous metals cannot keep pace with the development of society sooner or later.Thus,vast explorations on the advanced rechargeable battery systems were conducted.Compared with other battery systems,zinc ion battery systems with inherent safety,low cost were widely investigated.Especially,the zinc organic batteries based on the eco-efficiency organic cathodes were promising alternative advanced batteries for future energy storage systems.Therefore,various organics and different electrochemistry mechanisms were explored in the zinc batteries system.Herein,a timely review on elaborate analysis about functional groups,fundamentals,progress accompanied by the discussion on the four core issues:voltage,capacity,rate performance,cycle life was presented.Specifically,aiming at these issues,three levels of solution strategies:materials design concepts,morphology structure optimization and electrolyte environment were summarized and proposed for the development and innovation of zinc organic batteries.
基金supported by the National Natural Science Foundation of China(22072034,22001050,and 21873025)the China Postdoctoral Science Foundation(2020T130147,2020M681084,and 2022M710949)+1 种基金the Postdoctoral Foundation of Heilongjiang Province(LBH-Z19059)the Natural Science Foundation of Heilongjiang Youth Fund(YQ2021B002).
文摘Deep-level defects and random oriented configuration in perovskite crystallization process would cause the nonradiative recombination and further affect the performance of perovskite solar cells(PSCs).Herein,two metal-organic frameworks(MOFs)with tunable Lewis-base passivation sites have been constructed(Cd-Httb and Cd-Httb-BDC,Httb=5-(4-(1H-1,2,4-triazole-1-yl)benzyl)-1h-tetrazole,BDC=1,4-dicarboxybenzene)to eliminate deep-level defects and simultaneously as nanostructured heterogeneous nucleation seed to assist the growth of large-grained perovskite films.Compared with the control and Cd-Httb,Cd-Httb-BDC designed with mix-ligands strategy exhibited the enhanced inducted effect on the crystallization and nucleation of high-quality perovskite films during annealing process.Consequently,the resultant Cd-Httb-BDC-modified device achieved higher power conversion efficiency(PCE)(22.18%)than the control(20.89%)and Cd-Httb(21.56%).Meanwhile,the unencapsulated Cd-Httb-BDC-modified device still maintained 90%of initial PCE after 1500 h in ambient conditions and exhibited enhanced thermal stability(85℃ in N_(2) atmosphere).This work presented a successful example of mixligands strategy on construction of high-quality MOF-assisted perovskite films for high-efficient and stable PSCs.
基金supported by the National Natural Science Foundation of China (Nos. 21822407 and 22074154)Youth Innovation Promotion Association CAS (2021420)the Foundation for Sci & Tech Research Project of Gansu Province (20JR10RA045 and 20JR5RA573)。
文摘Covalent organic frameworks(COFs), as an emerging class of porous crystalline materials constructed by covalent links between the building monomers, have gained tremendous attention. Over the past 15 years, COFs have made rapid progress and substantial development in the chemistry and materials fields. However, the synthesis of COFs has been dominated by solvothermal methods for a long time and it usually involves high temperature, high pressure and toxic organic solvents, which created many challenges for environmental considerations. Recently,the exploration of new approaches for facile fabrication of COFs has aroused extensive interest. Hence, in this review, we comprehensively describe the synthetic strategies of COFs from the aspects of nonconventional heating methods and reaction media. In addition, the advantages,limitations and properties of the preparation methods are compared. Finally, we outline the main challenges and development prospects of the synthesis of COFs in the future and propose some possible solutions.
基金supported by the National Natural Science Foundation of China(Nos.21922409,21976131,21575100)Tianjin Research Program of Application Foundation and Advanced Technology(Nos.18JCZDJC37500,17JCYBJC20500).
文摘Organic fi eld-eff ect transistors(OFETs)are fabricated using organic semiconductors(OSCs)as the active layer in the form of thin fi lms.Due to its advantages of high sensitivity,low cost,compact integration,fl exibility,and printability,OFETs have been used extensively in the sensing area.For analysis platforms,the construction of sensing layers is a key element for their effi cient detection capability.The strategy used to immobilize biomolecules in these devices is especially important for ensuring that the sensing functions of the OFET are eff ective.Generally,analysis platforms are developed by modifying the gate/electrolyte or OSC/electrolyte interface using biomolecules,such as enzymes,antibodies,or deoxyribonucleic acid(DNA)to ensure high selectivity.To provide better or more convenient biological immobilization methods for researchers in this fi eld and thereby improve detection sensitivity,this review summarizes recent developments in the immobilization strategies used for biological macromolecules in OFETs,including cross-linking,physical adsorption,embedding,and chemical covalent binding.The infl uences of biomolecules on device performance are also discussed.
文摘This paper sets to explore management perceptions regarding the impact of operational process factors on strategy implementation in microfinance organisations in Kenya.Small and medium enterprises(SMEs)play a critical role in developing countries as a source of employment creation and a basis for industrialization.However,the sector receives inadequate financial support from commercial banks as it is considered to bear high risks and operational costs associate with lending small loan amounts.Microfinance organisations(MFOs)that serve this sector will need to expand their operations to increase their outreach to SMEs.Formulation and implementation of competitive strategies will enable MFOs to achieve growth and sustainability.Content,context and operational process factors appear to have a significance positive relationship to the level of strategy implementation.This paper is focusing on operational process factors impacting on strategy implementation and is part of a full study on the topic of strategy implementation in MFOs.Comprehensive literature review provided the theoretical framework for the study.Primary data were collected by means of a survey obtaining 300 self-administered questionnaires from managers in 135 MFOs in Kenya.The study revealed that the level of strategy implementation in MFOs in Kenya is moderate to high.This study has revealed that the operational process category of factors is more significant to the level of strategy implementation than content and context factors.Five operational process factors critical to strategy implementation include:operational planning and monitoring,management control systems,people-strategy fit,teamwork,and effective communication.Further,the level of strategy implementation has significance positive influence to MFOs’financial sustainability and outreach.Practical guidelines are provided to assist MFOs in developing countries to improve the level of strategy implementation by focusing on operational process factors.
文摘"Advance organizer"is a practical teaching strategy proposed by American modern educational psychologist Ausubel in 1960.This research considers learners'use of metacognitive strategy in the teaching activities of"advance organizer",trying to explore the effects of metacognitive strategy in the"advance organizer"teaching practices and testing whether"advance organizer"can effectively help students understand and retain reading materials.Further researches should be focused on how to conduct learners'"metacognitive strategy"training and employ learners'metacognitive strategies into"advance organizer"teaching activities.
基金the European Union-Next Generation EU,through the National Recovery and Resilience Plan of the Republic of Bulgaria,No.BG-RRP-2.004-0008.
文摘Solid organ transplant recipients face unique challenges in managing their im-munosuppressed status,making vaccination a critical consideration.This review aimed to comprehensively analyze current recommendations,evaluate the effi-cacy of vaccinations in this population,and assess safety concerns.We explored the latest evidence on vaccine types,timing,and potential benefits for transplant patients,highlighting the importance of individualized approaches for routinely used vaccines as well as coronavirus disease 2019 vaccines.By synthesizing avai-lable data,this review underscored the pressing need to optimize vaccination strategies,ensuring that transplant recipients can obtain the full protection against many pathogens while minimizing risks associated with their post-transplant immunosuppression.
基金the financial support from the National Natural Science Foundation of China(22008032,22108034,and 22102026)the Guangdong Basic and Applied Basic Research Foundation(2019A1515110706)+2 种基金the Guangdong Provincial Key Lab of Green Chemical Product Technology(GC202111)the Medical Science and Technology Research Foundation of Guangdong Province(A2021189)the Shandong Provincial Natural Science Foundation(ZR2018ZC1458)。
文摘Nanoscale hierarchically porous metal–organic frameworks(NHP-MOFs)have received unprecedented attention in many fields owing to their integration of the strengths of nanoscale size(<1μm)and hierarchical porous structure(micro-,meso-and/or macro-pores)of MOFs.This review focuses on recent advances in the main synthetic strategies for NHP-MOFs based on different metal ions(e.g.,Cu,Fe,Co,Zn,Al,Zr,and Cr),including the template method,composite technology,post-synthetic modification,in situ growth and the grind method.In addition,the mechanisms of synthesis,regulation techniques and the advantages and disadvantages of various methods are discussed.Finally,the challenges and prospects of the commercialisation of promising NHP-MOFs are also presented.The purpose of this review is to provide a road map for future design and development of NHP-MOFs for practical application.
基金the financial supporting from the NSFC(61975006,61675017)NSFRPSI(Y72Z090Q10)+3 种基金the NSFCQ(cstc2019jcyj-msxm X0400)the NYTPP(R52A199Z11)the YIPACAS(E0296104)the BNSF(4192049)。
文摘Small molecule organic photovoltaics(SMPVs) were prepared by utilizing liquid crystalline donor material BTR-Cl and two similar optical bandgap non-fullerene acceptor materials BTP-BO-4 F and Y6.The BTPBO-4 F and Y6 have the similar optical bandgap and different absorption coefficients.The corresponding binary SMPVs exhibit different short circuit current density(/sc)(20.38 vs.23.24 mA cm^(-2)),and fill factor(FF)(70.77% vs.67.21%).A 14.46% power conversion efficiency(PCE) is acquired in ternary SMPVs with 30 wt% Y6,companied with a JSC of 24.17 mA cm^(-2) a FF of 68.78% and an open circuit voltage(Voc) of 0.87 V.The improvement on PCE of ternary SMPVs should originate from the well trade-off between phase separation and photon harvesting of ternary active layers by incorporating 30 wt% Y6 in acceptors.This work may deliver insight onto the improved performance of SMPVs by superposing the superiorities of binary SMPVs with similar optical bandgap acceptors into one ternary cell.
基金The authors thank the support from the National Key Research and Development Program of China(2017YFA0206600)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(Grant No.QYZDB-SSW-SLH033)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB36000000)the National Natural Science Foundation of China(NSFC,Nos.21875052,51873044,52073067).
文摘Organic solar cells(OSCs)have received great attention for the prominent advantage of low-cost,light-weight and potential for fabricating flexible and semi-transparent device via roll-to-roll printing toward making better use of inexhaustible renewable clean energy during the past years[1-4].
文摘The development of efficient and cost‐effective metal‐free electrocatalysts for oxygen reduction reaction(ORR)has become crucial for electrochemical energy systems.However,reasonably validating and precisely regulating the active sites for designing optimized materials are still challenging.Herein,we report a precise and controllable tandem strategy to boost the ORR activity based on metal‐free covalent organic frameworks(MFCOFs)comprising imine‐N,thiophene‐S,or triazine‐N.Among these MFCOFs,post‐tandem BTT‐TAT‐COF structure displayed a more positive catalytic capability and excellent electrochemical stability,indicating that the synergistic catalysis of multiple active sites induced the ORR catalytic activity through the conjugated skeleton of the structure.Density‐functional theory calculations suggest that the series‐connected backbone contained highly effective electrocatalytic active centers and provided synergistic catalysis.More importantly,this strategy highlights new opportunities for the advancement of efficient COF‐based metal‐free ORR catalysts.
基金Sponsored by Fundamental Research Funds for the Central Universities(2452017103,2452018140)Humanities and Social Sciences Project of Northwest A&F University(2015RWYB37,2015RWYB39)
文摘Sunken yaodongs, or sunken yaodong houses, in Guanzhong are typical representatives of traditional Chinese dwellings. This paper analyzed the characteristics and existing problems of yaodongs, and put forward the idea of the organic renewal of sunken yaodongs with Dengjiapo Village in Yongshou County, Xianyang, Shaanxi as the research object.
文摘The present study investigated the impact from GOs (Graphic Organizers) upon reading comprehension ability. To this end, an OPT (Oxford Placement Test) was administered to a research population (N = 354) in order to homogenize it. On the basis of the test results, the population was sorted into three groups of reading-low, reading-mid, and reading-high students. Sixty participants with the lowest level of reading comprehension proficiency were randomly selected and assigned to an EG (Experimental Group) (N = 30) and a CG (Control Group) (N = 30). Afterwards, a TOEFL (Test of English as a Foreign Language) reading comprehension pretest was administered to both groups in order to determine their current level of reading proficiency. Then, the EG received 10 successive 90-minute sessions on GOs as post-reading strategies for expository text comprehension, while the CG received the same amount of treatment on other post-reading strategies. In the end, another TOEFL reading comprehension posttest was administered to the research groups to measure their reading comprehension performance level after the treatment. The results revealed that GOs were statistically more significant and effective for the low-skilled readers than other post-reading strategies.
文摘This paper argues for the adoption of concept attainment strategy when teaching math and shows the structure of this curriculum design that can substantially improve math instruction and comprehension in K-12 education.Initial findings based on informal surveys of teacher candidates indicate many of them do not have a clear understanding of the concepts they are expected to teach.The concept attainment strategy is a proven effective method used in social studies for teaching powerful concepts like democracy and liberty.One reason for many students feeling inadequate about their math skills stem from their lack of understanding of the key math concepts like area,perimeter,percent,and others.Poor understanding of the math fundamentals in early grades if not rectified,develops into a dislike for an incomprehensible subject.The concept attainment strategy is an inductive approach that allows the students to participate in knowledge construction and master the fundamental math skills.This paper shows how the structure of this social studies curriculum design can be adapted for teaching mathematics and invites practitioners and scholars to consider this approach to improve math instruction.