Climate change threatens cocoa quality, raising concerns regarding sustainable premium cocoa production. Evaluating the effectiveness of certification standards is imperative to address this concern effectively. A mul...Climate change threatens cocoa quality, raising concerns regarding sustainable premium cocoa production. Evaluating the effectiveness of certification standards is imperative to address this concern effectively. A multi-stage method was employed for a systematic review of 39 peer-reviewed articles to highlight the impacts of climate change on the biophysical environment of cocoa and its implications for adapting Geographical Indications (GIs). Additionally, a comprehensive review was conducted on climate-relevant standards of certificates in Ecuador, Indonesia, and Ghana. The findings of this study provide practical insights into possible difficulties that cocoa-producing countries may encounter in maintaining the distinctive flavours and quality trademarks of cocoa in the face of changing climate. Moreover, the findings emphasize the need for producer countries to prioritize viable adaptation and product differentiation strategies that meet sustainable marketing standards to protect GIs or place-based intellectual property. Furthermore, the findings indicate certificates require effective multi-level climate change management and environmental-social-governance principles that promote scientifically proven mitigation strategies, such as increasing soil organic carbon, zero deforestation, and reducing emissions while striving to leverage local adaptation policies to reduce location-specific vulnerability. Finally, certificates can accelerate the expansion, intensification, and redistribution of sustainable production for gains that outweigh the inconveniences caused by climate change.展开更多
This article explores the development of the Internet of Things(IoT)application technology course in higher vocational colleges under the background of“post,course,competition,certificate.”It first emphasizes the im...This article explores the development of the Internet of Things(IoT)application technology course in higher vocational colleges under the background of“post,course,competition,certificate.”It first emphasizes the importance of IoT talent training and course construction in higher vocational colleges and deeply analyzes the core concept of“post,course,competition,certificate”integration.In view of the problems faced in the course construction of IoT application technology in higher vocational colleges and the practical experience of Tianjin Vocational College of Mechanics and Electricity,the implementation strategy of the course construction of IoT application technology in higher vocational colleges is elaborated in detail based on the integrated concept of“post,course,competition,certificate.”展开更多
The core education function of higher vocational colleges is to train technical talents with high quality,so as to meet the needs of talents in the development stage of our society.Under the guidance of talent trainin...The core education function of higher vocational colleges is to train technical talents with high quality,so as to meet the needs of talents in the development stage of our society.Under the guidance of talent training,higher vocational colleges need to pay attention to establishing an all-round and three-dimensional education model,and promote innovation of higher vocational education on the basis of this.It is also a way to promote the innovation of higher vocational education to vigorously promote the construction of“post,course,competition,certificate”mode in the construction of education mode.Through the construction of“post,course,competition,certificate”mode,the education mode of higher vocational colleges is gradually improved,so as to strengthen the effectiveness of talent training in higher vocational colleges.Therefore,in this paper,the author puts forward some suggestions to promote the construction of the integrated education mode of the electronic information engineering technology major in higher vocational colleges,so as to help improve the talent training level of higher vocational colleges.展开更多
With the increasing proportion of renewable energy in the power market,the demands on government financial subsidies are gradually increasing.Thus,a joint green certificate-carbon emission right-electricity multi-mark...With the increasing proportion of renewable energy in the power market,the demands on government financial subsidies are gradually increasing.Thus,a joint green certificate-carbon emission right-electricity multi-market trading process is proposed to study the market-based strategy for renewable energy.Considering the commodity characteristics of green certificates and carbon emission rights,the dynamic cost models of green certificates and carbon rights are constructed based on the Rubinstein game and ladder pricing models.Furthermore,considering the irrational bidding behavior of energy suppliers in the actual electricity market,an evolutionary game based multi-market bidding optimization model is presented.Subsequently,it is solved using a composite differential evolutionary algorithm.Finally,the case study results reveal that the proposed model can increase profits and the consumption rate of renewable energy and reduce carbon emission.展开更多
This paper emphatically sums up the problems existing in the implementation of"1+X"certificate system by taking horticulture major in higher vocational colleges as an example.From the point of view of the im...This paper emphatically sums up the problems existing in the implementation of"1+X"certificate system by taking horticulture major in higher vocational colleges as an example.From the point of view of the improvement of"1+X"certificate system,the reform of talent training program,the improvement of teachers ability and summing up experience,this paper puts forward the updated working mode and ideas to provide strategies for accelerating the development of vocational education in southern Xinjiang.展开更多
Blockchain has proven to be an emerging technology in the digital world, changing the way everyone thinks about data security and bringing efficiency to several industries. It has already been applied to a wide range ...Blockchain has proven to be an emerging technology in the digital world, changing the way everyone thinks about data security and bringing efficiency to several industries. It has already been applied to a wide range of applications, from financial services and supply chain management to voting systems and identity verification. An organization must verify its candidates before selecting them. Choosing an unqualified candidate can ruin an organization’s reputation. In this paper, a blockchain-based academic certificate authentication system will be used to ensure authenticity and make the assertion of the decentralized system secure. However, the system will generate, authenticate and make corrections on academic certificates. Ultimately, some blockchain-based authentication systems already exist, they can’t correct any errors that occur during generation. A blockchain-based certificate authentication system was built using blockchain technology. Where admin could generate, authenticate and correct the certificate if necessary. The admin can also check how many times a certificate has been modified. Other users can only check the authenticity of the certificates. We’re using two blockchains to enable corrections. Blockchain technology can successfully implement a certificate authentication system. This system will eliminate doubts about the authenticity of certificates, provide fast responses, and ensure reliable and secure storage. The proposed system will help in many ways, such as providing a user-friendly university admission, and smooth job hiring process, etc. In conclusion, our proposed system can permanently eradicate certificate forgeries and create and promote trust in society.展开更多
The scarcity,high cost and susceptibility to CO of Platinum severely restrict its application in alkaline hydrogen oxidation reaction(HOR).Hybridizing Pt with other transition metals provides an effective strategy to ...The scarcity,high cost and susceptibility to CO of Platinum severely restrict its application in alkaline hydrogen oxidation reaction(HOR).Hybridizing Pt with other transition metals provides an effective strategy to modulate its catalytic HOR performance,but at the cost of mass activity due to the coverage of modifiers on Pt surface.Herein,we constructed dual junctions'Pt/nitrogen-doped carbon(Pt/NC)andδ-MoC/NC to modify electronic structure of Pt via interfacial electron transfer to acquire Pt-MoC@NC catalyst with electron-deficient Pt nanoparticles,simultaneously endowing it with high mass activity and durability of alkaline HOR.Moreover,the unique structure of Pt-MoC@NC endows Pt with a high COtolerance at 1,000 ppm CO/H_(2),a quality that commercial Pt-C catalyst lacks.The theoretical calculations not only confirm the diffusion of electrons from Pt/NC to Mo C/NC could occur,but also demonstrate the negative shift of Pt d-band center for the optimized binding energies of*H,*OH and CO.展开更多
Cooperation in energy systems is no longer limited to the distribution of electricity,and more attention is paid to the trading of green certificates(GCs).This paper proposed a cooperative method for photovoltaic(PV)a...Cooperation in energy systems is no longer limited to the distribution of electricity,and more attention is paid to the trading of green certificates(GCs).This paper proposed a cooperative method for photovoltaic(PV)and electric-to-hydrogen(EH)trading,including GC trading under risk management.First,a novel PV and EH model is established and the cooperation mechanism is analyzed.Meanwhile,PV and EH models were risk-controlled using the conditional value at risk to reduce the impact of the uncertainty of PV electricity and EH loads.Then,the PV-EH cooperative model was established based on cooperative game theory;this was then divided into two subproblems of“cooperative benefit maximization”and“transaction payment negotiation,”and the above two subproblems were solved distributively by alternating direction multiplier method(ADMM).Only energy transactions and price negotiations were conducted between the PV and EH,which can protect the privacy and confidentiality of each entity.Finally,the effectiveness of the cooperation model was verified using a practical engineering case.The simulation results show that the cooperation of the PV-EH can significantly improve the operational efficiency of each entity and the overall efficiency of the cooperation and realize the efficient redistribution of electricity and GC.展开更多
The low-intensity attack flows used by Crossfire attacks are hard to distinguish from legitimate flows.Traditional methods to identify the malicious flows in Crossfire attacks are rerouting,which is based on statistic...The low-intensity attack flows used by Crossfire attacks are hard to distinguish from legitimate flows.Traditional methods to identify the malicious flows in Crossfire attacks are rerouting,which is based on statistics.In these existing mechanisms,the identification of malicious flows depends on the IP address.However,the IP address is easy to be changed by attacks.Comparedwith the IP address,the certificate ismore challenging to be tampered with or forged.Moreover,the traffic trend in the network is towards encryption.The certificates are popularly utilized by IoT devices for authentication in encryption protocols.DTLShps proposed a new way to verify certificates for resource-constrained IoT devices by using the SDN controller.Based on DTLShps,the SDN controller can collect statistics on certificates.In this paper,we proposeCertrust,a framework based on the trust of certificates,tomitigate the Crossfire attack by using SDN for IoT.Our goal is threefold.First,the trust model is built based on the Bayesian trust system with the statistics on the participation of certificates in each Crossfire attack.Moreover,the forgetting curve is utilized instead of the traditional decay method in the Bayesian trust system for achieving a moderate decay rate.Second,for detecting the Crossfire attack accurately,a method based on graph connectivity is proposed.Third,several trust-based routing principles are proposed tomitigate the Crossfire attack.These principles can also encourage users to use certificates in communication.The performance evaluation shows that Certrust is more effective in mitigating the Crossfire attack than the traditional rerouting schemes.Moreover,our trust model has a more appropriate decay rate than the traditional methods.展开更多
The trusted sharing of Electronic Health Records(EHRs)can realize the efficient use of medical data resources.Generally speaking,EHRs are widely used in blockchain-based medical data platforms.EHRs are valuable privat...The trusted sharing of Electronic Health Records(EHRs)can realize the efficient use of medical data resources.Generally speaking,EHRs are widely used in blockchain-based medical data platforms.EHRs are valuable private assets of patients,and the ownership belongs to patients.While recent research has shown that patients can freely and effectively delete the EHRs stored in hospitals,it does not address the challenge of record sharing when patients revisit doctors.In order to solve this problem,this paper proposes a deletion and recovery scheme of EHRs based on Medical Certificate Blockchain.This paper uses cross-chain technology to connect the Medical Certificate Blockchain and the Hospital Blockchain to real-ize the recovery of deleted EHRs.At the same time,this paper uses the Medical Certificate Blockchain and the InterPlanetary File System(IPFS)to store Personal Health Records,which are generated by patients visiting different medical institutions.In addition,this paper also combines digital watermarking technology to ensure the authenticity of the restored electronic medical records.Under the combined effect of blockchain technology and digital watermarking,our proposal will not be affected by any other rights throughout the process.System analysis and security analysis illustrate the completeness and feasibility of the scheme.展开更多
Efficiently modulating the velocity distribution and flow pattern of non-Newtonian fluids is a critical challenge in the context of dual shaft eccentric mixers for process intensification,posing a significant barrier ...Efficiently modulating the velocity distribution and flow pattern of non-Newtonian fluids is a critical challenge in the context of dual shaft eccentric mixers for process intensification,posing a significant barrier for the existing technologies.Accordingly,this work reports a convenient strategy that changes the kinetic energy to controllably regulate the flow patterns from radial flow to axial flow.Results showed that the desired velocity distribution and flow patterns could be effectively obtained by varying the number and structure of baffles to change kinetic energy,and a more uniform velocity distribution,which could not be reached normally in standard baffle dual shaft mixers,was easily obtained.Furthermore,a comparative analysis of velocity and shear rate distributions is employed to elucidate the mechanism behind the generation of flow patterns in various dual-shaft eccentric mixers.Importantly,there is little difference in the power number of the laminar flow at the same Reynolds number,meaning that the baffle type has no effect on the power consumption,while the power number of both unbaffle and U-shaped baffle mixing systems decreases compared with the standard baffle mixing system in the transition flow.Finally,at the same rotational condition,the dimensionless mixing time of the U-shaped baffle mixing system is 15.3%and 7.9%shorter than that of the standard baffle and the unbaffle mixing system,respectively,which shows the advantage of the U-shaped baffle in stirring rate.展开更多
Anode-free Li-metal batteries are of significant interest to energy storage industries due to their intrinsically high energy.However,the accumulative Li dendrites and dead Li continuously consume active Li during cyc...Anode-free Li-metal batteries are of significant interest to energy storage industries due to their intrinsically high energy.However,the accumulative Li dendrites and dead Li continuously consume active Li during cycling.That results in a short lifetime and low Coulombic efficiency of anode-free Li-metal batteries.Introducing effective electrolyte additives can improve the Li deposition homogeneity and solid electrolyte interphase(SEI)stability for anode-free Li-metal batteries.Herein,we reveal that introducing dual additives,composed of LiAsF6 and fluoroethylene carbonate,into a low-cost commercial carbonate electrolyte will boost the cycle life and average Coulombic efficiency of NMC‖Cu anode-free Li-metal batteries.The NMC‖Cu anode-free Li-metal batteries with the dual additives exhibit a capacity retention of about 75%after 50 cycles,much higher than those with bare electrolytes(35%).The average Coulombic efficiency of the NMC‖Cu anode-free Li-metal batteries with additives can maintain 98.3%over 100 cycles.In contrast,the average Coulombic efficiency without additives rapidly decline to 97%after only 50 cycles.In situ Raman measurements reveal that the prepared dual additives facilitate denser and smoother Li morphology during Li deposition.The dual additives significantly suppress the Li dendrite growth,enabling stable SEI formation on anode and cathode surfaces.Our results provide a broad view of developing low-cost and high-effective functional electrolytes for high-energy and long-life anode-free Li-metal batteries.展开更多
Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSP...Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSPS and Cry1Ab/Ac was proposed and combined with a lateral flow immunochromatographic assay,named“Dual-RPA-LFD”,to visualize the dual detection of genetically modified(GM)crops.In which,the herbicide tolerance gene CP4-EPSPS and the insect resistance gene Cry1Ab/Ac were selected as targets taking into account the current status of the most widespread application of insect resistance and herbicide tolerance traits and their stacked traits.Gradient diluted plasmids,transgenic standards,and actual samples were used as templates to conduct sensitivity,specificity,and practicality assays,respectively.The constructed method achieved the visual detection of plasmid at levels as low as 100 copies,demonstrating its high sensitivity.In addition,good applicability to transgenic samples was observed,with no cross-interference between two test lines and no influence from other genes.In conclusion,this strategy achieved the expected purpose of simultaneous detection of the two popular targets in GM crops within 20 min at 37°C in a rapid,equipmentfree field manner,providing a new alternative for rapid screening for transgenic assays in the field.展开更多
The construction of a food certification system plays a vital role in upgrading export quality, which previous studies have largely overlooked. We match China's industry-level data of Green Food Certification with...The construction of a food certification system plays a vital role in upgrading export quality, which previous studies have largely overlooked. We match China's industry-level data of Green Food Certification with its HS6-digit export data of agri-food products to quantify the impact of Green Food Certification on export quality. We identify the significant and positive effect of Green Food Certification on export quality. The 2SLS estimation based on instrumental variables and a range of robustness checks confirm the validity and robustness of the benchmark conclusions. Further analysis discloses that Green Food Certification improves export quality by raising agricultural production efficiency and brand premiums. Heterogeneity analysis shows that the effect of Green Food Certification varies across regions, notably improving the quality of agri-food products exported to developed regions and regions with high levels of import supervision. Furthermore, among various product types, Green Food Certification significantly improves the export quality of primary products and products vulnerable to non-tariff measures. The above findings could guide the future development of agri-food quality certification systems, potentially leading to a transformation and promotion of the agri-food trade.展开更多
Multiple myeloma(MM)is the second most prevalent hematological malignancy.Current MM treatment strategies are hampered by systemic toxicity and suboptimal therapeutic efficacy.This study addressed these limitations th...Multiple myeloma(MM)is the second most prevalent hematological malignancy.Current MM treatment strategies are hampered by systemic toxicity and suboptimal therapeutic efficacy.This study addressed these limitations through the development of a potent MM-targeting chemotherapy strategy,which capitalized on the high binding affinity of alendronate for hydroxyapatite in the bone matrix and the homologous targeting of myeloma cell membranes,termed T-PB@M.The results from our investigations highlight the considerable bone affinity of T-PB@M,both in vitro and in vivo.Additionally,this material demonstrated a capability for drug release triggered by low pH conditions.Moreover,T-PB@M induced the generation of reactive oxygen species and triggered cell apoptosis through the poly(ADP-ribose)polymerase 1(PARP1)-Caspase-3-B-cell lymphoma-2(Bcl-2)pathway in MM cells.Notably,T-PB@M preferentially targeted bone-involved sites,thereby circumventing systemic toxic side effects and leading to prolonged survival of MM orthotopic mice.Therefore,this designed target-MM nanocarrier presents a promising and potentially effective platform for the precise treatment of MM.展开更多
We consider dual Toeplitz operators on the orthogonal complements of the FockSobolev spaces of all nonnegative real orders.First,for symbols in a certain class containing all bounded functions,we study the problem of ...We consider dual Toeplitz operators on the orthogonal complements of the FockSobolev spaces of all nonnegative real orders.First,for symbols in a certain class containing all bounded functions,we study the problem of when an operator which is finite sums of the dual Toeplitz products is compact or zero.Next,for bounded symbols,we construct a symbol map and exhibit a short exact sequence associated with the C^(*)-algebra generated by all dual Toeplitz operators with bounded symbols.展开更多
The model of“post-course competition certificate”can be the basic model of Building Information Modeling(BIM)course teaching in vocational colleges in the new era,and many vocational colleges have also made attempts...The model of“post-course competition certificate”can be the basic model of Building Information Modeling(BIM)course teaching in vocational colleges in the new era,and many vocational colleges have also made attempts to construct and apply this model in BIM courses and other professional courses.Based on the application of methods such as literature review and observation,it can be found that it is highly feasible in theory and practice to promote the innovation and reform of BIM curriculum based on this model.However,there are more influencing factors at the practical level,which can easily lead to some problems.In this paper,we will analyze the corresponding problems and put forward a more effective reform strategy of BIM course education innovation in combination with reality.展开更多
Aqueous rechargeable Zn-metal batteries(ARZBs)are considered one of the most promising candidates for grid-scale energy storage.However,their widespread commercial application is largely plagued by three major challen...Aqueous rechargeable Zn-metal batteries(ARZBs)are considered one of the most promising candidates for grid-scale energy storage.However,their widespread commercial application is largely plagued by three major challenges:The uncontrollable Zn dendrites,notorious parasitic side reactions,and sluggish Zn^(2+) ion transfer.To address these issues,we design a sustainable dual crosslinked cellulose hydrogel electrolyte,which has excellent mechanical strength to inhibit dendrite formation,high Zn^(2+) ions binding capacity to suppress side reaction,and abundant porous structure to facilitate Zn^(2+) ions migration.Consequently,the Zn||Zn cell with the hydrogel electrolyte can cycle stably for more than 400 h under a high current density of 10 mA cm^(−2).Moreover,the hydrogel electrolyte also enables the Zn||polyaniline cell to achieve high-rate and long-term cycling performance(>2000 cycles at 2000 mA g^(−1)).Remarkably,the hydrogel electrolyte is easily accessible and biodegradable,making the ARZBs attractive in terms of scalability and sustainability.展开更多
Ag-In-Ga-S(AIGS)quantum dots(QDs)have recently attracted great interests due to the outstanding optical properties and eco-friendly components,which are considered as an alternative replacement for toxic Pb-and Cd-bas...Ag-In-Ga-S(AIGS)quantum dots(QDs)have recently attracted great interests due to the outstanding optical properties and eco-friendly components,which are considered as an alternative replacement for toxic Pb-and Cd-based QDs.However,enormous attention has been paid to how to narrow their broadband spectra,ignoring the application advantages of the broadband emission.In this work,the AIGS QDs with controllable broad green-red dual-emission are first reported,which is achieved through adjusting the size distribution of QDs by controlling the nucleation and growth of AIGS crystals.Resultantly,the AIGS QDs exhibit broad dual-emission at green-and red-band evidenced by photoluminescence(PL)spectra,and the PL relative intensity and peak position can be finely adjusted.Furthermore,the dual-emission is the intrinsic characteristics from the difference in confinement effect of large particles and tiny particles confirmed by temperature-dependent PL spectra.Accordingly,the AIGS QDs(the size consists of 17 nm and 3.7 nm)with 530 nm and 630 nm emission could successfully be synthesized at 220°C.By combining the blue light-emitting diode(LED)chips and dual-emission AIGS QDs,the constructed white light-emitting devices(WLEDs)exhibit a continuous and broad spectrum like natural sunlight with the Commission Internationale de l’Eclairage(CIE)chromaticity coordinates of(0.33,0.31),a correlated color temperature(CCT)of 5425 K,color rendering index(CRI)of 90,and luminous efficacy of radiation(LER)of 129 lm/W,which indicates that the AIGS QDs have huge potential for lighting applications.展开更多
文摘Climate change threatens cocoa quality, raising concerns regarding sustainable premium cocoa production. Evaluating the effectiveness of certification standards is imperative to address this concern effectively. A multi-stage method was employed for a systematic review of 39 peer-reviewed articles to highlight the impacts of climate change on the biophysical environment of cocoa and its implications for adapting Geographical Indications (GIs). Additionally, a comprehensive review was conducted on climate-relevant standards of certificates in Ecuador, Indonesia, and Ghana. The findings of this study provide practical insights into possible difficulties that cocoa-producing countries may encounter in maintaining the distinctive flavours and quality trademarks of cocoa in the face of changing climate. Moreover, the findings emphasize the need for producer countries to prioritize viable adaptation and product differentiation strategies that meet sustainable marketing standards to protect GIs or place-based intellectual property. Furthermore, the findings indicate certificates require effective multi-level climate change management and environmental-social-governance principles that promote scientifically proven mitigation strategies, such as increasing soil organic carbon, zero deforestation, and reducing emissions while striving to leverage local adaptation policies to reduce location-specific vulnerability. Finally, certificates can accelerate the expansion, intensification, and redistribution of sustainable production for gains that outweigh the inconveniences caused by climate change.
基金2021 Tianjin Educational Science Planning Project“Research and Practice of Talent Cultivation Mode for IoT Majors in Higher Vocational Colleges under the Guidance of the‘1+X’Certificate System”(CJE210237)。
文摘This article explores the development of the Internet of Things(IoT)application technology course in higher vocational colleges under the background of“post,course,competition,certificate.”It first emphasizes the importance of IoT talent training and course construction in higher vocational colleges and deeply analyzes the core concept of“post,course,competition,certificate”integration.In view of the problems faced in the course construction of IoT application technology in higher vocational colleges and the practical experience of Tianjin Vocational College of Mechanics and Electricity,the implementation strategy of the course construction of IoT application technology in higher vocational colleges is elaborated in detail based on the integrated concept of“post,course,competition,certificate.”
文摘The core education function of higher vocational colleges is to train technical talents with high quality,so as to meet the needs of talents in the development stage of our society.Under the guidance of talent training,higher vocational colleges need to pay attention to establishing an all-round and three-dimensional education model,and promote innovation of higher vocational education on the basis of this.It is also a way to promote the innovation of higher vocational education to vigorously promote the construction of“post,course,competition,certificate”mode in the construction of education mode.Through the construction of“post,course,competition,certificate”mode,the education mode of higher vocational colleges is gradually improved,so as to strengthen the effectiveness of talent training in higher vocational colleges.Therefore,in this paper,the author puts forward some suggestions to promote the construction of the integrated education mode of the electronic information engineering technology major in higher vocational colleges,so as to help improve the talent training level of higher vocational colleges.
基金supported by the National Key R&D Program of China(2017YFB0902200).
文摘With the increasing proportion of renewable energy in the power market,the demands on government financial subsidies are gradually increasing.Thus,a joint green certificate-carbon emission right-electricity multi-market trading process is proposed to study the market-based strategy for renewable energy.Considering the commodity characteristics of green certificates and carbon emission rights,the dynamic cost models of green certificates and carbon rights are constructed based on the Rubinstein game and ladder pricing models.Furthermore,considering the irrational bidding behavior of energy suppliers in the actual electricity market,an evolutionary game based multi-market bidding optimization model is presented.Subsequently,it is solved using a composite differential evolutionary algorithm.Finally,the case study results reveal that the proposed model can increase profits and the consumption rate of renewable energy and reduce carbon emission.
基金Supported by School-level Cultivation Project of Hetian Vocational and Technical College(HZ-2022-14)Science and Technology Research and Development Plan Project in Hetian Area(20220219).
文摘This paper emphatically sums up the problems existing in the implementation of"1+X"certificate system by taking horticulture major in higher vocational colleges as an example.From the point of view of the improvement of"1+X"certificate system,the reform of talent training program,the improvement of teachers ability and summing up experience,this paper puts forward the updated working mode and ideas to provide strategies for accelerating the development of vocational education in southern Xinjiang.
文摘Blockchain has proven to be an emerging technology in the digital world, changing the way everyone thinks about data security and bringing efficiency to several industries. It has already been applied to a wide range of applications, from financial services and supply chain management to voting systems and identity verification. An organization must verify its candidates before selecting them. Choosing an unqualified candidate can ruin an organization’s reputation. In this paper, a blockchain-based academic certificate authentication system will be used to ensure authenticity and make the assertion of the decentralized system secure. However, the system will generate, authenticate and make corrections on academic certificates. Ultimately, some blockchain-based authentication systems already exist, they can’t correct any errors that occur during generation. A blockchain-based certificate authentication system was built using blockchain technology. Where admin could generate, authenticate and correct the certificate if necessary. The admin can also check how many times a certificate has been modified. Other users can only check the authenticity of the certificates. We’re using two blockchains to enable corrections. Blockchain technology can successfully implement a certificate authentication system. This system will eliminate doubts about the authenticity of certificates, provide fast responses, and ensure reliable and secure storage. The proposed system will help in many ways, such as providing a user-friendly university admission, and smooth job hiring process, etc. In conclusion, our proposed system can permanently eradicate certificate forgeries and create and promote trust in society.
基金supported by the National Natural Science Foundation of China (Grant Nos.52072272,52171145 and 22109120)the Zhejiang Provincial Natural Science Foundation of China (LQ21B030002)+1 种基金the Zhejiang Provincial Special Support Program for High-level Talents (2019R52042)the Key programs for Science and Technology Innovation of Wenzhou (ZG2022037)。
文摘The scarcity,high cost and susceptibility to CO of Platinum severely restrict its application in alkaline hydrogen oxidation reaction(HOR).Hybridizing Pt with other transition metals provides an effective strategy to modulate its catalytic HOR performance,but at the cost of mass activity due to the coverage of modifiers on Pt surface.Herein,we constructed dual junctions'Pt/nitrogen-doped carbon(Pt/NC)andδ-MoC/NC to modify electronic structure of Pt via interfacial electron transfer to acquire Pt-MoC@NC catalyst with electron-deficient Pt nanoparticles,simultaneously endowing it with high mass activity and durability of alkaline HOR.Moreover,the unique structure of Pt-MoC@NC endows Pt with a high COtolerance at 1,000 ppm CO/H_(2),a quality that commercial Pt-C catalyst lacks.The theoretical calculations not only confirm the diffusion of electrons from Pt/NC to Mo C/NC could occur,but also demonstrate the negative shift of Pt d-band center for the optimized binding energies of*H,*OH and CO.
基金supported in part by the National Natural Science Foundation of China(No.5197707).
文摘Cooperation in energy systems is no longer limited to the distribution of electricity,and more attention is paid to the trading of green certificates(GCs).This paper proposed a cooperative method for photovoltaic(PV)and electric-to-hydrogen(EH)trading,including GC trading under risk management.First,a novel PV and EH model is established and the cooperation mechanism is analyzed.Meanwhile,PV and EH models were risk-controlled using the conditional value at risk to reduce the impact of the uncertainty of PV electricity and EH loads.Then,the PV-EH cooperative model was established based on cooperative game theory;this was then divided into two subproblems of“cooperative benefit maximization”and“transaction payment negotiation,”and the above two subproblems were solved distributively by alternating direction multiplier method(ADMM).Only energy transactions and price negotiations were conducted between the PV and EH,which can protect the privacy and confidentiality of each entity.Finally,the effectiveness of the cooperation model was verified using a practical engineering case.The simulation results show that the cooperation of the PV-EH can significantly improve the operational efficiency of each entity and the overall efficiency of the cooperation and realize the efficient redistribution of electricity and GC.
基金supported by Joint Funds of the National Natural Science Foundation of China and Xinjiang under Project U1603261.
文摘The low-intensity attack flows used by Crossfire attacks are hard to distinguish from legitimate flows.Traditional methods to identify the malicious flows in Crossfire attacks are rerouting,which is based on statistics.In these existing mechanisms,the identification of malicious flows depends on the IP address.However,the IP address is easy to be changed by attacks.Comparedwith the IP address,the certificate ismore challenging to be tampered with or forged.Moreover,the traffic trend in the network is towards encryption.The certificates are popularly utilized by IoT devices for authentication in encryption protocols.DTLShps proposed a new way to verify certificates for resource-constrained IoT devices by using the SDN controller.Based on DTLShps,the SDN controller can collect statistics on certificates.In this paper,we proposeCertrust,a framework based on the trust of certificates,tomitigate the Crossfire attack by using SDN for IoT.Our goal is threefold.First,the trust model is built based on the Bayesian trust system with the statistics on the participation of certificates in each Crossfire attack.Moreover,the forgetting curve is utilized instead of the traditional decay method in the Bayesian trust system for achieving a moderate decay rate.Second,for detecting the Crossfire attack accurately,a method based on graph connectivity is proposed.Third,several trust-based routing principles are proposed tomitigate the Crossfire attack.These principles can also encourage users to use certificates in communication.The performance evaluation shows that Certrust is more effective in mitigating the Crossfire attack than the traditional rerouting schemes.Moreover,our trust model has a more appropriate decay rate than the traditional methods.
基金supported by the National Natural Science Foundation of China under grant 61972207,U1836208,U1836110,61672290the Major Program of the National Social Science Fund of China under Grant No.17ZDA092+2 种基金by the National Key R&D Program of China under grant 2018YFB1003205by the Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET)fundby the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)fund.
文摘The trusted sharing of Electronic Health Records(EHRs)can realize the efficient use of medical data resources.Generally speaking,EHRs are widely used in blockchain-based medical data platforms.EHRs are valuable private assets of patients,and the ownership belongs to patients.While recent research has shown that patients can freely and effectively delete the EHRs stored in hospitals,it does not address the challenge of record sharing when patients revisit doctors.In order to solve this problem,this paper proposes a deletion and recovery scheme of EHRs based on Medical Certificate Blockchain.This paper uses cross-chain technology to connect the Medical Certificate Blockchain and the Hospital Blockchain to real-ize the recovery of deleted EHRs.At the same time,this paper uses the Medical Certificate Blockchain and the InterPlanetary File System(IPFS)to store Personal Health Records,which are generated by patients visiting different medical institutions.In addition,this paper also combines digital watermarking technology to ensure the authenticity of the restored electronic medical records.Under the combined effect of blockchain technology and digital watermarking,our proposal will not be affected by any other rights throughout the process.System analysis and security analysis illustrate the completeness and feasibility of the scheme.
基金supported by the National Natural Science Foundation of China(22078030,52021004)Natural Science Foundation of Chongqing(2022NSCO-LZX0014)+1 种基金Fundamental Research Funds for the Central Universities(2022CDJQY-005,2023CDJXY-047)National Key Research and Development Project(2022YFC3901204)。
文摘Efficiently modulating the velocity distribution and flow pattern of non-Newtonian fluids is a critical challenge in the context of dual shaft eccentric mixers for process intensification,posing a significant barrier for the existing technologies.Accordingly,this work reports a convenient strategy that changes the kinetic energy to controllably regulate the flow patterns from radial flow to axial flow.Results showed that the desired velocity distribution and flow patterns could be effectively obtained by varying the number and structure of baffles to change kinetic energy,and a more uniform velocity distribution,which could not be reached normally in standard baffle dual shaft mixers,was easily obtained.Furthermore,a comparative analysis of velocity and shear rate distributions is employed to elucidate the mechanism behind the generation of flow patterns in various dual-shaft eccentric mixers.Importantly,there is little difference in the power number of the laminar flow at the same Reynolds number,meaning that the baffle type has no effect on the power consumption,while the power number of both unbaffle and U-shaped baffle mixing systems decreases compared with the standard baffle mixing system in the transition flow.Finally,at the same rotational condition,the dimensionless mixing time of the U-shaped baffle mixing system is 15.3%and 7.9%shorter than that of the standard baffle and the unbaffle mixing system,respectively,which shows the advantage of the U-shaped baffle in stirring rate.
基金fellowship support from the China Scholarship Council
文摘Anode-free Li-metal batteries are of significant interest to energy storage industries due to their intrinsically high energy.However,the accumulative Li dendrites and dead Li continuously consume active Li during cycling.That results in a short lifetime and low Coulombic efficiency of anode-free Li-metal batteries.Introducing effective electrolyte additives can improve the Li deposition homogeneity and solid electrolyte interphase(SEI)stability for anode-free Li-metal batteries.Herein,we reveal that introducing dual additives,composed of LiAsF6 and fluoroethylene carbonate,into a low-cost commercial carbonate electrolyte will boost the cycle life and average Coulombic efficiency of NMC‖Cu anode-free Li-metal batteries.The NMC‖Cu anode-free Li-metal batteries with the dual additives exhibit a capacity retention of about 75%after 50 cycles,much higher than those with bare electrolytes(35%).The average Coulombic efficiency of the NMC‖Cu anode-free Li-metal batteries with additives can maintain 98.3%over 100 cycles.In contrast,the average Coulombic efficiency without additives rapidly decline to 97%after only 50 cycles.In situ Raman measurements reveal that the prepared dual additives facilitate denser and smoother Li morphology during Li deposition.The dual additives significantly suppress the Li dendrite growth,enabling stable SEI formation on anode and cathode surfaces.Our results provide a broad view of developing low-cost and high-effective functional electrolytes for high-energy and long-life anode-free Li-metal batteries.
基金supported by the Scientific and Innovative Action Plan of Shanghai(21N31900800)Shanghai Rising-Star Program(23QB1403500)+4 种基金the Shanghai Sailing Program(20YF1443000)Shanghai Science and Technology Commission,the Belt and Road Project(20310750500)Talent Project of SAAS(2023-2025)Runup Plan of SAAS(ZP22211)the SAAS Program for Excellent Research Team(2022(B-16))。
文摘Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSPS and Cry1Ab/Ac was proposed and combined with a lateral flow immunochromatographic assay,named“Dual-RPA-LFD”,to visualize the dual detection of genetically modified(GM)crops.In which,the herbicide tolerance gene CP4-EPSPS and the insect resistance gene Cry1Ab/Ac were selected as targets taking into account the current status of the most widespread application of insect resistance and herbicide tolerance traits and their stacked traits.Gradient diluted plasmids,transgenic standards,and actual samples were used as templates to conduct sensitivity,specificity,and practicality assays,respectively.The constructed method achieved the visual detection of plasmid at levels as low as 100 copies,demonstrating its high sensitivity.In addition,good applicability to transgenic samples was observed,with no cross-interference between two test lines and no influence from other genes.In conclusion,this strategy achieved the expected purpose of simultaneous detection of the two popular targets in GM crops within 20 min at 37°C in a rapid,equipmentfree field manner,providing a new alternative for rapid screening for transgenic assays in the field.
基金supported by the National Natural Science Foundation of China(72061147002)the National Social Science Foundation of China(18ZDA074)。
文摘The construction of a food certification system plays a vital role in upgrading export quality, which previous studies have largely overlooked. We match China's industry-level data of Green Food Certification with its HS6-digit export data of agri-food products to quantify the impact of Green Food Certification on export quality. We identify the significant and positive effect of Green Food Certification on export quality. The 2SLS estimation based on instrumental variables and a range of robustness checks confirm the validity and robustness of the benchmark conclusions. Further analysis discloses that Green Food Certification improves export quality by raising agricultural production efficiency and brand premiums. Heterogeneity analysis shows that the effect of Green Food Certification varies across regions, notably improving the quality of agri-food products exported to developed regions and regions with high levels of import supervision. Furthermore, among various product types, Green Food Certification significantly improves the export quality of primary products and products vulnerable to non-tariff measures. The above findings could guide the future development of agri-food quality certification systems, potentially leading to a transformation and promotion of the agri-food trade.
基金supported by the National Natural Science Foundation of China(52073145 and 82004081)the Jiangsu Talent Professor Program,Jiangsu Innovation Project of Graduate Student(KYCX23-2192)+1 种基金the National Natural Science Foundation of Nanjing University of Chinese Medicine(NZY82004081)the Special Grants of China Postdoctoral Science Foundation(2021T140792).
文摘Multiple myeloma(MM)is the second most prevalent hematological malignancy.Current MM treatment strategies are hampered by systemic toxicity and suboptimal therapeutic efficacy.This study addressed these limitations through the development of a potent MM-targeting chemotherapy strategy,which capitalized on the high binding affinity of alendronate for hydroxyapatite in the bone matrix and the homologous targeting of myeloma cell membranes,termed T-PB@M.The results from our investigations highlight the considerable bone affinity of T-PB@M,both in vitro and in vivo.Additionally,this material demonstrated a capability for drug release triggered by low pH conditions.Moreover,T-PB@M induced the generation of reactive oxygen species and triggered cell apoptosis through the poly(ADP-ribose)polymerase 1(PARP1)-Caspase-3-B-cell lymphoma-2(Bcl-2)pathway in MM cells.Notably,T-PB@M preferentially targeted bone-involved sites,thereby circumventing systemic toxic side effects and leading to prolonged survival of MM orthotopic mice.Therefore,this designed target-MM nanocarrier presents a promising and potentially effective platform for the precise treatment of MM.
基金supported by the NSFC(12271134,11771401)supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2019R1I1A3A01041943)。
文摘We consider dual Toeplitz operators on the orthogonal complements of the FockSobolev spaces of all nonnegative real orders.First,for symbols in a certain class containing all bounded functions,we study the problem of when an operator which is finite sums of the dual Toeplitz products is compact or zero.Next,for bounded symbols,we construct a symbol map and exhibit a short exact sequence associated with the C^(*)-algebra generated by all dual Toeplitz operators with bounded symbols.
基金Chongqing Municipal Education Science Planning Project+Educational Reform Special Project+Practice Research on Integrated Teaching Reform of“Post-Course Competition Certificate”for BIM Intelligent Construction Major in Vocational Schools(Project number:K23ZG3250169)。
文摘The model of“post-course competition certificate”can be the basic model of Building Information Modeling(BIM)course teaching in vocational colleges in the new era,and many vocational colleges have also made attempts to construct and apply this model in BIM courses and other professional courses.Based on the application of methods such as literature review and observation,it can be found that it is highly feasible in theory and practice to promote the innovation and reform of BIM curriculum based on this model.However,there are more influencing factors at the practical level,which can easily lead to some problems.In this paper,we will analyze the corresponding problems and put forward a more effective reform strategy of BIM course education innovation in combination with reality.
基金This work was financially supported by the National Natural Science Foundation of China(52173106 and 22375154).
文摘Aqueous rechargeable Zn-metal batteries(ARZBs)are considered one of the most promising candidates for grid-scale energy storage.However,their widespread commercial application is largely plagued by three major challenges:The uncontrollable Zn dendrites,notorious parasitic side reactions,and sluggish Zn^(2+) ion transfer.To address these issues,we design a sustainable dual crosslinked cellulose hydrogel electrolyte,which has excellent mechanical strength to inhibit dendrite formation,high Zn^(2+) ions binding capacity to suppress side reaction,and abundant porous structure to facilitate Zn^(2+) ions migration.Consequently,the Zn||Zn cell with the hydrogel electrolyte can cycle stably for more than 400 h under a high current density of 10 mA cm^(−2).Moreover,the hydrogel electrolyte also enables the Zn||polyaniline cell to achieve high-rate and long-term cycling performance(>2000 cycles at 2000 mA g^(−1)).Remarkably,the hydrogel electrolyte is easily accessible and biodegradable,making the ARZBs attractive in terms of scalability and sustainability.
基金supported by National Natural Science Foundation of China(Grant Nos.52272166,22205214,and 12204427).
文摘Ag-In-Ga-S(AIGS)quantum dots(QDs)have recently attracted great interests due to the outstanding optical properties and eco-friendly components,which are considered as an alternative replacement for toxic Pb-and Cd-based QDs.However,enormous attention has been paid to how to narrow their broadband spectra,ignoring the application advantages of the broadband emission.In this work,the AIGS QDs with controllable broad green-red dual-emission are first reported,which is achieved through adjusting the size distribution of QDs by controlling the nucleation and growth of AIGS crystals.Resultantly,the AIGS QDs exhibit broad dual-emission at green-and red-band evidenced by photoluminescence(PL)spectra,and the PL relative intensity and peak position can be finely adjusted.Furthermore,the dual-emission is the intrinsic characteristics from the difference in confinement effect of large particles and tiny particles confirmed by temperature-dependent PL spectra.Accordingly,the AIGS QDs(the size consists of 17 nm and 3.7 nm)with 530 nm and 630 nm emission could successfully be synthesized at 220°C.By combining the blue light-emitting diode(LED)chips and dual-emission AIGS QDs,the constructed white light-emitting devices(WLEDs)exhibit a continuous and broad spectrum like natural sunlight with the Commission Internationale de l’Eclairage(CIE)chromaticity coordinates of(0.33,0.31),a correlated color temperature(CCT)of 5425 K,color rendering index(CRI)of 90,and luminous efficacy of radiation(LER)of 129 lm/W,which indicates that the AIGS QDs have huge potential for lighting applications.