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Multi-valent mRNA vaccines against monkeypox enveloped or mature viron surface antigens demonstrate robust immune response and neutralizing activity 被引量:7
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作者 Niubing Zhang Xiang Cheng +15 位作者 Yilong Zhu Ouyang Mo Huiqing Yu Liqi Zhu Juan Zhang Linlin Kuang Ying Gao Ruiyuan Cao Xiaozhen Liang Haikun Wang Honglin Li Song Li Wu Zhong Xuan Li Xiao Li Pei Hao 《Science China(Life Sciences)》 SCIE CAS CSCD 2023年第10期2329-2341,共13页
Monkeypox was declared a global health emergency by the World Health Organization,and as of March 2023,86,000 confirmed cases and 111 deaths across 110 countries have been reported.Its causal agent,monkeypox virus(MPV... Monkeypox was declared a global health emergency by the World Health Organization,and as of March 2023,86,000 confirmed cases and 111 deaths across 110 countries have been reported.Its causal agent,monkeypox virus(MPV)belongs to a large family of double-stranded DNA viruses,Orthopoxviridae,that also includes vaccinia virus(VACV)and others.MPV produces two distinct forms of viral particles during its replication cycles:the enveloped viron(EV)that is released via exocytosis,and the mature viron(MV)that is discharged through lysis of host cells.This study was designed to develop multi-valent m RNA vaccines against monkeypox EV and MV surface proteins,and examine their efficacy and mechanism of action.Four m RNA vaccines were produced with different combinations of surface proteins from EV(A35R and B6R),MV(A29L,E8L,H3L and M1R),or EV and MV,and were administered in Balb/c mice to assess their immunogenicity potentials.A dynamic immune response was observed as soon as seven days after initial immunization,while a strong Ig G response to all immunogens was detected with ELISA after two vaccinations.The higher number of immunogens contributed to a more robust total Ig G response and correlating neutralizing activity against VACV,indicating the additive potential of each immunogen in generating immune response and nullifying VACV infection.Further,the m RNA vaccines elicited an antigen-specific CD4^(+)T cell response that is biased towards Th1.The m RNA vaccines with different combinations of EVand MV surface antigens protected a mouse model from a lethal dose VACV challenge,with the EV and MV antigens-combined vaccine offering the strongest protection.These findings provide insight into the protective mechanism of multi-valent m RNAvaccines against MPV,and also the foundation for further development of effective and safe m RNA vaccines for enhanced protection against monkeypox virus outbreak. 展开更多
关键词 monkeypox virus enveloped and mature viron multi-valent mRNA vaccines immune response neutralizing antibody
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Environmental Stability and Transmissibility of Enveloped Viruses at Varied Animate and Inanimate Interfaces
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作者 Li Zeng Junya Li +9 位作者 Meilin Lv Zikang Li Linlin Yao Jie Gao Qi Wu Ziniu Wang Xinyue Yang Gang Tang Guangbo Qu Guibin Jiang 《Environment & Health》 2023年第1期15-31,共17页
Enveloped viruses have been the leading causative agents of viral epidemics in the past decade,including the ongoing coronavirus disease 2019 outbreak.In epidemics caused by enveloped viruses,direct contact is a commo... Enveloped viruses have been the leading causative agents of viral epidemics in the past decade,including the ongoing coronavirus disease 2019 outbreak.In epidemics caused by enveloped viruses,direct contact is a common route of infection,while indirect transmissions through the environment also contribute to the spread of the disease,although their significance remains controversial.Bridging the knowledge gap regarding the influence of interfacial interactions on the persistence of enveloped viruses in the environment reveals the transmission mechanisms when the virus undergoes mutations and prevents excessive disinfection during viral epidemics.Herein,from the perspective of the driving force,partition efficiency,and viral survivability at interfaces,we summarize the viral and environmental characteristics that affect the environmental transmission of viruses.We expect to provide insights for virus detection,environmental surveillance,and disinfection to limit the spread of severe acute respiratory syndrome coronavirus 2. 展开更多
关键词 enveloped virus environmental transmission interface SURVIVABILITY SARS-CoV-2
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Gold nanoparticles combat enveloped RNA virus by affecting organelle dynamics 被引量:2
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作者 Fangzhou Li Qianqian Huang +5 位作者 Ziran Zhou Qiongge Guan Fei Ye Baoying Huang Weisheng Guo Xing-Jie Liang 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2023年第9期4244-4251,共8页
Enveloped RNA viruses are a group of viruses with an outer membrane derived from a host cell and a genome consisting of ribonucleic acid(RNA).These viruses rely on host cell machinery and organelles to replicate and a... Enveloped RNA viruses are a group of viruses with an outer membrane derived from a host cell and a genome consisting of ribonucleic acid(RNA).These viruses rely on host cell machinery and organelles to replicate and assemble new virus particles.However,the interaction between viruses and host organelles may be disrupted by nanomaterials,such as gold nanoparticles(AuNPs)with unique physical and chemical properties.In this study,we investigated the effects of AuNPs with different surface charge properties on the subcellular structure and function of mammalian cells,and their effects on two representative enveloped RNA viruses:lentivirus and human coronavirus OC43(HCoV-OC43)antiviral potential.By comparing the subcellular effects of AuNPs with different surface charge properties,we found that treatment with AuNPs with positive surface charges induced more significant disruption of subcellular structures than neutrally charged AuNPs and negatively charged AuNPs,mainly manifested in lysosomes and Cytoskeletal disorders.The antiviral effect of the surface positively charged AuNPs was further evaluated using lentivirus and HCoV-OC43.The results showed that AuNPs had a significant inhibitory effect on both lentivirus and HCoV-OC43 without obvious side effects.In conclusion,our study provides insights into the mechanism of action and biocompatibility of AuNP in biological systems,while supporting the potential of targeting organelle dynamics against enveloped RNA viruses. 展开更多
关键词 PROPERTIES PARTICLES ENVELOPE
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A novel Bocaparvovirus in goats:Genetic features,phylogenetic analysis,and epidemiological implications
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作者 Kegu Ji’e Falong Yang +6 位作者 Ai Ran Yang Su Taichun Gao Lanmuyi Gou Shenglin Li Zihan Xia Keha-mo Abi 《Journal of Integrative Agriculture》 2025年第8期3291-3296,共6页
Bocapavovirus,a member of the genus Bocaparvovirus within the subfamily Parvovirinae and the family Parvoviridae,is a small,non-enveloped,single-stranded DNA virus.This pathogen poses health risks to both humans and a... Bocapavovirus,a member of the genus Bocaparvovirus within the subfamily Parvovirinae and the family Parvoviridae,is a small,non-enveloped,single-stranded DNA virus.This pathogen poses health risks to both humans and animals.The Bocaparvovirus genome. 展开更多
关键词 SMALL PARVOVIRIDAE phylogenetic analysis epidemiological implications non enveloped novel bocaparvovirus parvovirinae genetic features
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A new multi-DOF envelope forming process for fabricating spiral bevel gears with back taper tooth 被引量:1
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作者 Xinghui HAN Yanhui WANG +3 位作者 Lin HUA Wuhao ZHUANG Fangyan ZHENG Wei FENG 《Chinese Journal of Aeronautics》 2025年第1期568-585,共18页
Spiral bevel gears are critical transmission components,and are widely used in the aerospace field.This paper proposes a new multi-DOF envelope forming process for fabricating spiral bevel gears.Firstly,the multi-DOF ... Spiral bevel gears are critical transmission components,and are widely used in the aerospace field.This paper proposes a new multi-DOF envelope forming process for fabricating spiral bevel gears.Firstly,the multi-DOF envelope forming principle of spiral bevel gears is proposed.Secondly,the design methods for the envelope tool geometry and movement are proposed based on the envelope geometry and movement relationships.Thirdly,the metal flow and tooth filling laws are revealed through 3D FE simulation of the multi-DOF envelope forming process of a typical spiral bevel gear.Fourthly,a new method for separating the envelope tool and the formed spiral bevel gear with back taper tooth is proposed to avoid their interference.Finally,experiments on multi-DOF envelope forming of this typical spiral bevel gear are conducted using new heavy load multi-DOF envelope forming equipment.The simulation and experimental results show the feasibility of the proposed multi-DOF envelope forming process for fabricating spiral bevel gears with back taper tooth and the corresponding process design methods. 展开更多
关键词 Multi-DOF envelope forming Spiral bevel gear Back taper tooth Metal flow Process design
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Global Ports Efficiency and Productivity Using DEA-MPI Approach
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作者 Calvin Elorm Atsunyo Bernard Kwei Tetteh 《Open Journal of Applied Sciences》 2025年第2期433-449,共17页
Ports are crucial to the economy of many nations;thus, numerous studies have been conducted on port efficiency and productivity. This study analyses the efficiency and productivity of some major global ports namely, P... Ports are crucial to the economy of many nations;thus, numerous studies have been conducted on port efficiency and productivity. This study analyses the efficiency and productivity of some major global ports namely, Port of Singapore, Rotterdam, Antwerp and Durban. The main objectives of this study are to determine the level of operational efficiency of the mentioned ports, measure and evaluate the ports’ productivity changes and lastly to investigate the factors influencing the productivity changes of the ports studied. To achieve these objectives, Data Envelopment Analysis (DEA-BCC) model was used to determine the technical and operational efficiencies of the ports and Malmquist productivity index was employed to calculate the various productivity levels. The results of the study can guide stakeholders to formulate their operational strategies for port efficiency and productivity. The study also has policy suggestions that are uniquely targeted to Africa’s issues and potential. 展开更多
关键词 EFFICIENCY PRODUCTIVITY Data Envelopment Analysis Malmquist Productivity Index
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Mechanical Properties of CAC Under Biaxial Compression:A 3D Mesoscopic Study
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作者 CHEN Xusheng MA Haiyan YU Hongfa 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第S1期156-166,共11页
Studies on coral aggregate concrete(CAC)mainly focus on uniaxial stress conditions.However,concrete structures often experience complex stress conditions in practical engineering.It is essential to investigate the mec... Studies on coral aggregate concrete(CAC)mainly focus on uniaxial stress conditions.However,concrete structures often experience complex stress conditions in practical engineering.It is essential to investigate the mechanical behavior and failure mechanisms of CAC under multiaxial stress conditions.This paper employs a 3D mesoscale model that considers the actual size,shape,and spatial distribution of aggregates.The reliability of the model and material parameters is verified through comparison with existing experimental data.Subsequently,the model is used to systematically study the mechanical properties,failure modes,and failure processes of C40 CAC under the biaxial compression.The numerical results are compared with the experimental results of CAC and ordinary portland concrete(OPC).The results indicate that the failure modes of CAC under the biaxial compression are diagonal shear failure.The biaxial compressive strength and elastic modulus of CAC are greater than those under uniaxial stress and exhibit a significant intermediate principal stress effect.The biaxial compressive strength reaches its maximum value when the stress ratio is 0.5,which is consistent with the conclusions for OPC.Finally,failure criteria and strength envelopes for CAC under the biaxial compression are established in order to provide a reference for analyzing the strength characteristics and structural design of CAC. 展开更多
关键词 coral aggregate concrete(CAC) biaxial compression stress ratio failure mode strength envelope
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New unloading criterion for enhancing multi-stage triaxial tests based on radial strain gradient
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作者 Guodong Jin Shujath Ali Syed +3 位作者 Héctor JoséGonzález-Pérez Hyung Tae Kwak Ali Abdullah Yousef Ali Abdullah Al Dhamen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期4735-4744,共10页
This paper presents a new criterion for determining the unloading points quantitatively and consistently in a multi-stage triaxial test.The radial strain gradient(RSG)is first introduced as an arc tangent function of ... This paper presents a new criterion for determining the unloading points quantitatively and consistently in a multi-stage triaxial test.The radial strain gradient(RSG)is first introduced as an arc tangent function of the rate of change of radial strain to time.RSG is observed to correlate closely with the stress state of a compressed sample,and reaches a horizontal asymptote as approaching failure.For a given rock type,RSG value at peak stress is almost the same,irrespective of the porosity and permeability.These findings lead to the development of RSG criterion:Unloading points can be precisely determined at the time when RSG reaches a pre-determined value that is a little smaller than or equal to the RSG at peak stress.The RSG criterion is validated against other criteria and the single-stage triaxial test on various types of rocks.Failure envelopes from the RSG criterion match well with those from single-stage tests.A practical procedure is recommended to use the RSG criterion:an unconfined compression or single-stage test is first conducted to determine the RSG at peak stress for one sample,the unloading point is then selected to be a value close to the RSG at peak stress,and the multi-stage test is finally performed on another sample using the pre-selected RSG unloading criterion.Generally,the RSG criterion is applicable for any type of rocks,especially brittle rocks,where other criteria are not suitable.Further,it can be practically implemented on the most available rock mechanical testing instruments. 展开更多
关键词 Radial strain gradient Unloading criterion Multi-stage triaxial test Mohr-coulomb failure envelope
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Flight envelope constrained UAV shipboard landing control within an identified quiescent period
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作者 Cheng ZHANG Tao SONG +1 位作者 Hong TAO Tao JIANG 《Chinese Journal of Aeronautics》 2025年第8期498-511,共14页
UAV shipboard landing poses significant challenges in terms of safety and efficiency,due to the oscillatory ship motion caused by wave interactions and wind gusts,especially in rough sea states.To solve this issue,a f... UAV shipboard landing poses significant challenges in terms of safety and efficiency,due to the oscillatory ship motion caused by wave interactions and wind gusts,especially in rough sea states.To solve this issue,a flight envelope constrained fixed-time control strategy is proposed to achieve a reliable UAV landing on a maneuvering ship.Firstly,a sliding data window autoregressive model is designed to predict the ship's roll and pitch motions,which are accordingly utilized to identify an appropriate quiescent period for safe landing.Subsequently,a barrier-function-based nonsingular terminal sliding mode controller is developed to eliminate the tracking errors within the identified quiescent period,while ensuring the errors remain bounded to satisfy flight envelope constraints.In particular,lumped disturbance components are estimated by integrating a fixed-time disturbance observer and compensated in the controller.The key advantage of the proposed approach is that it well balances the control requirements between precise landing position and safe landing attitude,guaranteeing both steady-state performance and transient behavior of the tracking error.Finally,comparative Gazebo simulations in different sea state scenarios are conducted to verify the satisfactory control performance. 展开更多
关键词 Unmanned aerial vehicle Shipboard landing Ship motion prediction Flight envelope Sliding mode control
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Adjusting Accuracy of Digital Image Correlation Through Variable Subsets and Application in Airship Envelope
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作者 ZHU Fangtao VWANG Quanbao +1 位作者 XIE Weicheng DUAN Dengping 《Journal of Shanghai Jiaotong university(Science)》 2025年第2期239-251,共13页
The stratospheric airship is affected by harsh conditions in the stratosphere environment.To ensure the safety of the airship,it is necessary to detect the material state of the airship envelope.Since digital image co... The stratospheric airship is affected by harsh conditions in the stratosphere environment.To ensure the safety of the airship,it is necessary to detect the material state of the airship envelope.Since digital image correlation possesses non-contact strain measurement ability,this paper explores the infuence of different shapes of the subset on measurement accuracy.Through the results,it is found that increasing the aspect ratio of subsets can improve the strain accuracy measured in the c-direction,and reducing the aspect ratio can improve the strain accuracy measured in the y-direction.This trend becomes more obvious as the strain increases.Based on this discovery,a subset adaptive algorithm is proposed.The feasibility of the algorithm is verified by experiments,and the precision of strain measurement can be effectively improved by adjusting the threshold value.Therefore,the algorithm can be utilized to increase the measurement accuracy in the larger strain direction without changing the size of the subset. 展开更多
关键词 shape of subset digital image correlation strain of airship envelope self-adaptive selection
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JCMT observations of CO, SO_(2), and a U-line in circumstellar envelopes of four O-rich AGB stars
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作者 Yanan Feng Xiaohu Li +4 位作者 Sheng-Li Qin Tom J.Millar Ryszard Szczerba Zhenzhen Miao Juan Tuo 《Chinese Physics B》 2025年第6期693-699,共7页
The circumstellar envelopes(CSE) of asymptotic giant branch(AGB) stars are abundant in molecular emissions, offering valuable insights into the physical and chemical conditions of these evolving stars. In this paper, ... The circumstellar envelopes(CSE) of asymptotic giant branch(AGB) stars are abundant in molecular emissions, offering valuable insights into the physical and chemical conditions of these evolving stars. In this paper, we report observations of two molecules(CO and SO_(2)) toward four O-rich AGB stars using the James Clerk Maxwell Telescope(JCMT). We detected an unusual SO_(2) spectral feature comprising both broad and narrow components in IK Tau and AP Lyn. The broad line profiles may originate from thermal molecular emission, while the narrow profiles could come from other species(or masers) or astrophysical phenomena occurring within the CSEs of the AGB stars, such as episodic mass loss, bipolar outflows, or emissions associated with the complex physical processes near the central star. The narrow lines of SO_(2) may also arise from vibrationally excited emissions. Additionally, we observed the same U-line in both TX Cam and IK Tau, which may originate from the molecule N^(17)O. We analyzed the identified molecular lines using rotational diagrams to determine their excitation temperatures, column densities, and fractional abundances. This information aids in the constructing of reliable astrochemical models for a more detailed examination of the target stars. The narrow component of the SO_(2) line suggests unusual astrophysical phenomena, making IK Tau and AP Lyn particularly intriguing for further investigation to fully understand the physical processes at play in these sources. 展开更多
关键词 asymptotic giant branch circumstellar envelopes SO_(2)
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TR Equipment Manufacturing Enterprise Technology Innovation Performance Evaluation
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作者 Huinan Gao 《Proceedings of Business and Economic Studies》 2025年第2期9-16,共8页
The correct evaluation of enterprise technological innovation performance is the premise and foundation to improve the efficiency of enterprise innovation.This paper first puts forward the index system of enterprise t... The correct evaluation of enterprise technological innovation performance is the premise and foundation to improve the efficiency of enterprise innovation.This paper first puts forward the index system of enterprise technological innovation performance evaluation,then establishes the model of technological innovation performance evaluation,explores the quantitative evaluation of enterprise innovation performance by using the DEA method,and finally makes an empirical study on the technological innovation performance of the TR enterprise. 展开更多
关键词 Equipment manufacturing industry Innovation performance Data envelopment analysis
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Forming Laws and Processing Designing Methods for Multi-DOF Envelope Forming Process of Brake Pad Baseboard
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作者 Xinghui Han Wei Xiong +3 位作者 Wuhao Zhuang Lin Hua Fangyan Zheng Jingyu Liu 《Chinese Journal of Mechanical Engineering》 2025年第6期501-516,共16页
To improve braking performance and achieve lightweight in transport equipment,it is necessary to implement overall plastic forming manufacturing of the brake pad baseboard(BPB),which is the core safety component of th... To improve braking performance and achieve lightweight in transport equipment,it is necessary to implement overall plastic forming manufacturing of the brake pad baseboard(BPB),which is the core safety component of the brake system.This study presents an innovative multi-DOF envelope forming(MDFEF)process to realize the plastic forming of BPB with thin skin and high reinforcing ribs.The MDFEF principle for BPB,and the design methods for the envelope mold are first presented.Through FE simulations,the behavior of metal flow,uneven growth pattern of reinforcing ribs,evolution of equivalent strain and evolution of forming force in MDFEF of BPB are investigated.To realize MDFEF,an innovative MDFEF equipment driven by parallel linkages is exploited.The force states of linkages in MDFEF are calculated,and the reasonable mold position is determined to reduce the maximum force on the linkages and improve the service performance of MDFEF equipment.The MDFEF experiments of BPB are conducted and qualified BPB is obtained,which demonstrates that the presented MDFEF process and equipment are applicable to manufacture BPB with thin skin and high reinforcing ribs. 展开更多
关键词 Multi-DOF envelope forming Component with thin skin and reinforcing ribs Brake pad baseboard Forming laws Processing designing
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A novel sliding mode control method with enhanced permanent magnet synchronous motor parameter identification for heavy load multi-DOF envelope forming press
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作者 Xinghui HAN Xin CHEN +2 位作者 Fangyan ZHENG Lin HUA Wuhao ZHUANG 《Chinese Journal of Aeronautics》 2025年第11期396-412,共17页
To achieve the manufacturing of Thin-Wall and High-Rib Components(TWHRC)with high precision,a novel heavy load Multi-DOF Envelope Forming Press(MEFP)with Parallel Kinematic Mechanism(PKM),driven by six Permanent Magne... To achieve the manufacturing of Thin-Wall and High-Rib Components(TWHRC)with high precision,a novel heavy load Multi-DOF Envelope Forming Press(MEFP)with Parallel Kinematic Mechanism(PKM),driven by six Permanent Magnet Synchronous Motors(PMSMs),is developed.However,on account of the heavy forming load,the PMSM parameters are in great variation.Meanwhile,the PMSM is always in a transient state caused by fast time-varying forming load,resulting in low identification precision of varied PMSM parameters and control precision of PMSM under traditional parameter identification methods.To solve this problem,a novel Sliding Mode Control Method with Enhanced PMSM Parameter Identification(SMCMEPPI)for heavy load MEFP is proposed.Firstly,the kinematic model of MEFP is established.Secondly,the variation law of PMSM parameters under heavy load is revealed.Thirdly,an enhanced PMSM parameter identification method is proposed,in which the q axis current of PMSM is used to represent the changing rate of forming load and the adjustment factor is first proposed to remove improper input of PMSM parameter identification online.Fourthly,the Electromechanical Coupling Dynamic Model(ECDM)of MEFP,which includes identified PMSM parameters,is developed.Finally,based on the developed ECDM,a novel SMCMEPPI is proposed to realize the high-precision control of heavy load MEFP.The experimental results indicate that the proposed SMCMEPPI can significantly improve the control precision of heavy load MEFP. 展开更多
关键词 Electromechanical coupling dynamic model Enhanced parameter identification Multi-DOF envelope forming press Parallel kinematic mechanism Sliding mode control
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Energy and Buildings
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《建筑节能(中英文)》 2025年第12期20-20,共1页
https://www.sciencedirect.com/journal/energy-and-buildings/vol/348/suppl/C Volume 348,1 December 2025[OA](1)Active prefabricated façade with building-integrated photovoltaic(APF-BIPV)technologies for high energy ... https://www.sciencedirect.com/journal/energy-and-buildings/vol/348/suppl/C Volume 348,1 December 2025[OA](1)Active prefabricated façade with building-integrated photovoltaic(APF-BIPV)technologies for high energy efficient building renovation:a systematic review of recent research advancements by Graziano Salvalai,Feiyu Zhao,Article 116440 Abstract:Active Prefabricated Fa ade with building-integrated photovoltaic(APF-BIPV)technologies used in the prefabricated building envelope component offer a promising approach to energy-efficient building renovation,combining renewable energy generation with modular construction advantages.This study systematically reviews APF-BIPV technologies,assessing their technological development,performance optimization,economic feasibility,and policy implications.Based on PRISMA methodology,the review includes not only peer-reviewed publications from Scopus and Web of Science but also analyzes research outputs from European-funded projects,highlighting the significant technological advancements that have transformed prefabricated fa ade components from basic cladding systems into highly integrated,multifunctional building elements,integrating PV technology for renewable energy production. 展开更多
关键词 prefabricated fa ade active prefabricated facade technological development economic feasibility prefabricated building envelope component building integrated photovoltaic APF BIPV energy efficient building renovation
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Measuring technical efficiency of Chinese nonferrous metals enterprises on a background of industry consolidation 被引量:5
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作者 危平 唐慧泉 +1 位作者 陈瑶 陈晓红 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第9期2797-2806,共10页
Since 2009, Chinese nonferrous metals industry has been carried out industry consolidation with strong support by the central government. This work examined technical efficiency of Chinese nonferrous metals firms and ... Since 2009, Chinese nonferrous metals industry has been carried out industry consolidation with strong support by the central government. This work examined technical efficiency of Chinese nonferrous metals firms and its change during the period of 2007 and 2011. Based on financial data from nonferrous metals listed companies, technical efficiency of nonferrous metal minerals mining firms and nonferrous metal smelting, pressing and processing firms was estimated respectively using the data envelopment analysis (DEA) method. It was found that, in both sectors, number of pure technical and scale inefficient firms dominated over efficient ones. Overall, their technical and scale efficiency tended to be very low after 2009. In particular, efficiency scores of nonferrous metal smelting, pressing and processing firms fluctuated greatly during the research period. And a limited number of large leading firms were able to maintain 100% efficiency score in the industry, while efficiency of most of other leading firms has declined since 2009. 展开更多
关键词 industry consolidation nonferrous metals finns data envelopment analysis (DEA) technical efficiency scale efficiency CONGLOMERATE
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紧框架分析模型下的模糊图像盲复原 被引量:2
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作者 李骜 雷天鸣 +1 位作者 陈德运 孙广路 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2017年第6期931-938,共8页
在基于稀疏表示模型的图像盲复原问题中,模糊核估计与稀疏模型的选取是影响盲复原性能的两个关键因素。针对传统基于稀疏表示盲复原方法的不足,本文提出一种基于紧框架分析模型的图像盲复原方法。该方法将盲复原问题分裂为两个迭代的子... 在基于稀疏表示模型的图像盲复原问题中,模糊核估计与稀疏模型的选取是影响盲复原性能的两个关键因素。针对传统基于稀疏表示盲复原方法的不足,本文提出一种基于紧框架分析模型的图像盲复原方法。该方法将盲复原问题分裂为两个迭代的子问题,分别是基于梯度图像的模糊核估计与基于紧框架分析模型的非盲图像复原。在核估计问题中,提出同时约束核稀疏性及一阶微分平滑特性,进一步提高了核估计精度。在紧框架非盲图像复原问题中,提出一种基于Moreau envelope函数的数值计算方法,有效地解决紧框架复原模型的不可微和不可分离性。实验结果表明,本文复原方法在图像细节恢复与客观评价指标方面均优于传统复原算法。 展开更多
关键词 图像盲复原 紧框架 核估计 迭代优化 正则化 Moreau envelope函数
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Embryogenesis,Germination,Structure and Cotyledon Dimorphism of Zea mays Embryo 被引量:2
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作者 冯九焕 徐雪宾 +3 位作者 刘向东 章崇玲 梁秀兰 吴万春 《Acta Botanica Sinica》 CSCD 2003年第6期712-723,共12页
A series of new cognitions on the morphogenesis of maize ( Zea mays L.) embryo have been obtained with scanning electron microscopy and semi-thin section techniques. 1. The proembryo. The proembryo from zygotic cell d... A series of new cognitions on the morphogenesis of maize ( Zea mays L.) embryo have been obtained with scanning electron microscopy and semi-thin section techniques. 1. The proembryo. The proembryo from zygotic cell divisions may be divided into three parts: proper, hypoblast and suspensor. The suspensor is short and small, and only exists transiently. As to the hypoblast there is a growth belt, which promotes elongation of the hypoblast. Eventually the upper portion of the hypoblast contributes to the formation of the coleorhiza and the remainder dries up, sticking to the end of the coleorhiza. 2. The maize embryo possesses dorsiventrality and cotyledon dimorphism. During early proembryo stage, the dorsiventrality appears in the proper of the embryo. On the ventral side, the cells are small with dense cytoplasm and few vacuoles. On the dorsal side, the cells are larger with lower cytoplasmic density and have more vacuoles. During later proembryo stage, the proper develops into two parts: the ventrum and the dorsurn. The ventrum rises up from the center of the ventral side. The dorsurn is composed of the marginal area of the ventral side and the whole dorsal side of the proper. During young embryo development, the ventrum differentiates into the coleoptile, apical meristem, hypocotyl, radicle and the main part of the coleorhiza. What is more important, the emergence of coleoptile primordium and radicular initials occur at the axis of the proper, then the coleoptile primordium expands from its two ends toward left and right to form a ring, and the endogenous radicular initials expand in all directions to form a conical radicular tip. All these morphogenetic activities of the ventrum follow a bilateral symmetrical pattern. The dorsurn forms the scutellum. primordium. Then the scutellum primordium, expands rapidly toward the left, right, front and back, while thickening itself, so as to make all components originating from the ventrum become hidden in the longitudinal groove of the scutellum. Lastly, the left and right lateral scales emerge from the edges of the longitudinal groove and expand toward the central line of the axis. As a consequence, morphologically, the bilateral symmetry of the ventral side of the embryo is revealed entirely. Morphogenetically, the coleoptile primordium and apical meristem in maize are similar to the coleoptile (apical cotyledon) and apex formation of the nice embryo, so the coleoptile of the maize embryo can also be considered as an apical cotyledon. The scutellum is a lateral cotyledon. These dimorphic cotyledons of the maize embryo originate from the dorsiventrality of the proper. 3. The true morphological structure of the maize embryo is recognized and its developmental stages are established. A maize embryo is a hypocotyl, in which the apical part is the shoot apex (or plumule) with the coleoptile, the central part consists mainly of the hypocotyl with a lateral cotyledon (scutellum), and the basal part is the radicle with coleorhiza. The left and right lateral scales derived from the scutellum overlap at the ventral side, leaving only two little pores at both ends of the seam from which the coleoptile and coleorhiza can be seen. The four sequential stages of maize embryonic development are as follows: (1) proembryo, stage. This stage covers a period from zygotic cell division to the appearance of the dorsum and ventrum. (2) ventrum rapid differentiation stage. (3) scutellum rapid expansion stage. (4) lateral scale development stage (or embryonic envelope formation stage). 4. To obtain a median longitudinal section perpendicular to the ventral surface is crucial for recognizing the genuine morphological structure of the maize embryo. 展开更多
关键词 Zea mays EMBRYOGENESIS hypoblast dorsiventrality cotyledon dimorphism embryonic envelope (lateral cotyledon) coleoptile (apical cotyledon)
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The Structure of Oryza Embryos and Their Dimorphic Cotyledons 被引量:2
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作者 徐雪宾 刘向东 +2 位作者 章崇玲 吴万春 韩惠珍 《Acta Botanica Sinica》 CSCD 2002年第1期15-21,共7页
It has been generally held in botany that Oryza sativa L. is a monocotyledon. Based on studies of rice embryo development we confirmed that rice embryo has two dimorphic cotyledons rather than just one cotyledo... It has been generally held in botany that Oryza sativa L. is a monocotyledon. Based on studies of rice embryo development we confirmed that rice embryo has two dimorphic cotyledons rather than just one cotyledon. In the present study we attempt to know if the morphology of embryos in other species of Oryza differs from O. sativa and if these embryos have dimorphic cotyledon. Two types of embryo structures were observed in 22 species and/or subspecies of genus Oryza under the scanning electron microscope. Type 1, the O.sativa type, which is characterized by ventral scale and lateral scales, was found in 16 species. Type 2, the O. meyeriana (Zoll. et Mor. ex Steud.) Baill. ssp. tuberculata W. C. Wu et Y. G. Lu, G. C. Wang type, with no ventral scale and lateral scales, was found in 6 species and subspecies. The embryogenic process of O.sativa and O.meyeriana sub. tuberculata showed that the scutellum primordium, coleorhiza primordium, coleoptile primordium and shoot apical meristem directly differentiate from proembryo. The former two later develop into the embryo envelope, which is the outside cotyledon; the coleoptile primordium develops into the coleoptile with the shape of inverted empty cone surrounding and covering the growth cone, which is the apical cotyledon. Both types of rice embryos have dimorphic cotyledons. The structural difference between them is that the scutellum primordium of the young embryo in type 2 does not differentiate ventral scale and lateral scales while the embryo of type 1 does. The dimorphic cotyledons of embryo of Oryza plants originate from the dorsiventrality of proembryo. 展开更多
关键词 genus Oryza EMBRYOGENESIS dimorphic cotyledon dorsiventrality embryonic envelope (outside cotyledon) scutellum and coleoptile (apical cotyledon)
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海南省环境质量与经济发展DEA有效性评价 被引量:4
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作者 俞花美 肖明 +1 位作者 吴季秋 葛成军 《工业安全与环保》 北大核心 2012年第6期68-70,共3页
以海南省环境质量作为研究对象,结合海南经济发展的现状构建评价指标体系,运用DEA模型对海南省环境质量与经济发展有效性进行评价。结果表明,DEA的有效性与地区经济的发展水平紧密相关,DEA有效性与经济发展好坏基本一致;部分区域的环境... 以海南省环境质量作为研究对象,结合海南经济发展的现状构建评价指标体系,运用DEA模型对海南省环境质量与经济发展有效性进行评价。结果表明,DEA的有效性与地区经济的发展水平紧密相关,DEA有效性与经济发展好坏基本一致;部分区域的环境污染物排放集中与转移,实现了经济与环境发展协调的DEA有效。在此基础上,对DEA无效的背后因素做了进一步分析,提出提升资源利用效率和优化经济结构才是实现环境质量与经济协调发展的根本途径。 展开更多
关键词 海南省 环境与经济 DEA(Data Envelopment Analysis)
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