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Discussion on Gas Safety Protection Management in Steel Plants
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作者 Han Lu Jingyu Huang 《Frontiers of Metallurgical Industry》 2024年第1期34-36,共3页
The necessity of establishing gas protection station in iron and steel works is demonstrated,issues of strengthening the management of gas safety protection,studying new technology of gas protection,adapting to the ne... The necessity of establishing gas protection station in iron and steel works is demonstrated,issues of strengthening the management of gas safety protection,studying new technology of gas protection,adapting to the needs of modernization and building large scale and intelligent iron and steel works are discussed.Relevant sug-gestions are also put forward. 展开更多
关键词 iron and steel works GASES safety protection
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Self-actuating protection mechanisms for safer lithium-ion batteries
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作者 Yang Luo Chunchun Sang +3 位作者 Kehan Le Hao Chen Hui Li Xinping Ai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期181-198,共18页
Safety issue is still a problem nowadays for the large-scale application of lithium-ion batteries(LIBs)in electric vehicles and energy storage stations.The unsafe behaviors of LIBs arise from the thermal run-away,whic... Safety issue is still a problem nowadays for the large-scale application of lithium-ion batteries(LIBs)in electric vehicles and energy storage stations.The unsafe behaviors of LIBs arise from the thermal run-away,which is intrinsically triggered by the overcharging and overheating.To improve the safety of LIBs,various protection strategies based on self-actuating reaction control mechanisms(SRCMs)have been proposed,including redox shuttle,polymerizable monomer additive,potential-sensitive separator,thermal shutdown separator,positive-temperature-coefficient electrode,thermally polymerizable addi-tive,and reversible thermal phase transition electrolyte.As build-in protection mechanisms,these meth-ods can sensitively detect either the temperature change inside battery or the potential change of the electrode,and spontaneously shut down the electrode reaction at risky conditions,thus preventing the battery from going into thermal runaway.Given their advantages in enhancing the intrinsic safety of LIBs,this paper overviews the research progresses of SRCMs after a brief introduction of thermal runaway mechanism and limitations of conventional thermal runaway mitigating measures.More importantly,the current states and issues,key challenges,and future developing trends of SRCTs are also discussed and outlined from the viewpoint of practical application,aiming at providing insights and guidance for developing more effective SRCMs for LIBs. 展开更多
关键词 Li-ion battery safety Thermal runaway Thermal protection Overcharge protection
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Research on Evaluating Index of Lightning Protection Safety Performance of High Voltage Overhead Transmission Line 被引量:4
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作者 Yi Luo Jingzhou Jiang +1 位作者 Yu Nong Shizuo Li 《Journal of Power and Energy Engineering》 2014年第4期680-686,共7页
In order to improve the lightning protection performance of transmission lines, lightning protection management has been divided into every tower that lightning protection performance has been evaluated respectively. ... In order to improve the lightning protection performance of transmission lines, lightning protection management has been divided into every tower that lightning protection performance has been evaluated respectively. According to factors such as landform, span, tower type, grounding resistance, isolator type, and so on, relative ratio of tripping operation of every tower in the line has been calculated to evaluate its lightning protection safety performance, it is beneficial to operation maintenance and lightning reconstruction of transmission lines. 展开更多
关键词 Transmission LINES LIGHTNING protection safety Performance EVALUATING INDEX RATIO of LIGHTNING TRIPPING Operation
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Study on the Priority and Interaction of Food Security,Food Safety and Environmental Protection 被引量:1
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作者 Tang Bulong 《学术界》 CSSCI 北大核心 2017年第11期294-303,共10页
Food security, food safety and environmental protection are major livelihood issues in front of the Chinese people. The priorities of the three are different, and there is mutually dependent and contradictory relation... Food security, food safety and environmental protection are major livelihood issues in front of the Chinese people. The priorities of the three are different, and there is mutually dependent and contradictory relationship among them. Facing the triple pressures of food security, food safety, and environmental protection, this paper analyzes the priority of the three from the historical development, then further analyzes the interaction between food security,food safety and environmental protection and finally puts forward the healthy development of food security, food safety and environmental protection, and the proper settlement of the three problems. 展开更多
关键词 FOOD security FOOD safety ENVIRONMENTAL protection PRIORITY INTERACTIVE RELATIONSHIP
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International law obligations for the disposal of Fukushima nuclear-contaminated water under the principles of nuclear safety
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作者 Wei Gong 《Chinese Journal of Population,Resources and Environment》 2024年第1期10-19,共10页
The disposal of contaminated water from Japan’s Fukushima nuclear power plant is a significant international nuclear safety issue with considerable cross-border implications.This matter requires compliance not only w... The disposal of contaminated water from Japan’s Fukushima nuclear power plant is a significant international nuclear safety issue with considerable cross-border implications.This matter requires compliance not only with the law of the sea but also with the principles of nuclear safety under international law.These principles serve as the overarching tenet of international and China’s domestic nuclear laws,applicable to nuclear facilities and activities.The principle of safety in nuclear activities is fully recognized in international and domestic laws,carrying broad legal binding force.Japan’s discharge of nuclear-contaminated water into the sea violates its obligations under the principle of safety in nuclear activities,including commitments to optimum protection,as low as reasonably practicable,and prevention.The Japanese government and the International Atomic Energy Agency(IAEA)have breached the obligation of optimum protection by restricting the scope of assessments,substituting core concepts,and shielding dissenting views.In the absence of clear radiation standards,they have acted unilaterally without fulfilling the obligation as low as reasonably practicable principle.The discharge of Fukushima nuclear-contaminated water poses an imminent and unpredictable risk to all countries worldwide,including Japanese residents.Japan and the IAEA should fulfill their obligations under international law regarding disposal,adhering to the principles of nuclear safety,including optimum protection,the obligation as low as reasonably practicable,and prevention through multilateral cooperation.Specifically,the obligation to provide optimum protection should be implemented by re-evaluating the most reliable disposal technologies and methods currently available and comprehensively assessing various options.The standard of the obligation as low as reasonably practicable requires that the minimization of negative impacts on human health,livelihoods,and the environment should not be subordinated to considerations of cutting costs and expenses.Multilateral cooperation should be promoted through the establishment of sound multilateral long-term monitoring mechanisms for the discharge of nuclear-contaminated water,notification and consultation obligations,and periodic assessments.These obligations under international law were fulfilled after the accidents at the Three Mile Island and Chernobyl nuclear power plants.The implications of the principles of nuclear safety align with the concept of building a community of shared future for nuclear safety advocated by China.In cases of violations of international law regarding the disposal of nuclear-contaminated water that jeopardize the concept of a community of a shared future for nuclear safety,China can also rely on its own strength to promote the implementation of due obligations through self-help. 展开更多
关键词 Principles of nuclear safety Disposal of nuclear-contaminated water Optimum protection Prevention As low as reasonably achievable
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Safety,immunogenicity,and cross-species protection of a plasmid DNA encoding Plasmodium falciparum SERA5 polypeptide,microbial epitopes and chemokine genes in mice and olive baboons
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作者 Nyamongo Onkoba Ruth M.Mumo +3 位作者 Horace Ochanda Charles Omwandho Hastings S.Ozwara Thomas G.Egwang 《The Journal of Biomedical Research》 CAS CSCD 2017年第4期321-332,共12页
Incorporation of biomolecular epitopes to malarial antigens should be explored in the development of straintranscending malarial vaccines.The present study sought to determine safety,immunogenicity and cross-species e... Incorporation of biomolecular epitopes to malarial antigens should be explored in the development of straintranscending malarial vaccines.The present study sought to determine safety,immunogenicity and cross-species efficacy of Plasmodium falciparum serine repeat antigen 5 polypeptide co-expressed with epitopes of BacilleCalmette Guerin(BCG),tetanus toxoid(TT) and a chemokine gene.Olive baboons and BALB/c mice were randomly assigned into vaccine and control groups.The vaccine group animals were primed and boosted twice with pIRES plasmids encoding the SERA5 + BCG + TT alone,or with either CCL5 or CCL20 and the control group with pIRES plasmid vector backbone.Mice and baboons were challenged with P.berghei ANKA and P.knowlesi H strain parasites,respectively.Safety was determined by observing for injection sites reactogenicities,hematology and clinical chemistry.Parasitaemia and survivorship profiles were used to determine cross-species efficacy,and T cell phenotypes,Th1-,Th2-type,T-regulatory immune responses and antibody responses were assessed to determine vaccine immunogenicity.The pSeBCGTT plasmid DNA vaccines were safe and induced Thl-,Th2-type,and Tregulatory responses vaccinated animals showed enhanced CD4~+(P〈0.01),CD 8~+ T cells(P〈 0.001) activation and IgG anti-SE36 antibodies responses(P〈 0.001) at week 4 and 8 post vaccination compared to the control group.Vaccinated mice had a 31.45-68.69%cumulative parasite load reduction and 60%suppression in baboons(P〈0.05)and enhanced survivorship(P〈 0.001) with no clinical signs of malaria compared to the control group.The results showed that the vaccines were safe,immunogenic and conferred partial cross-species protection. 展开更多
关键词 malaria DNA vaccines serine repeat antigen chemokines cross-species protection immunogenicity safety
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Technical Analysis and Improvement of the Pedestrian Safety Protection of a Car Hood
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作者 SONG Xin-ping HUANG Hu SHI Run-wei 《International Journal of Plant Engineering and Management》 2010年第1期54-59,共6页
The pedestrian protection technology must be used in automotive design if China-made automotives want to compete and grow strong in the world in the future. In this paper, a CAE simulation analysis is made for a domes... The pedestrian protection technology must be used in automotive design if China-made automotives want to compete and grow strong in the world in the future. In this paper, a CAE simulation analysis is made for a domestic sedan car hood to check whether it meet the pedestrian safety protection laws and regulations. Results show that the original car cannot meet the demands of the rules. In order to meet the standards of the pedustrian protection rules, the car hood should undergo structural improvements. Tested again by CAE simulation analysis, the car after a series of improved design can reached the 3-star class EuroNCAP( Euro New Car Assessment Program)standard of the car pedestrian safety protection laws and regulations. 展开更多
关键词 sedan car engine hood pedestrian safety protection improved design
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Importance of establishing radiation protection culture in Radiology Department 被引量:4
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作者 Agapi Ploussi Efstathios P Efstathopoulos 《World Journal of Radiology》 CAS 2016年第2期142-147,共6页
The increased use of ionization radiation for diagnostic and therapeutic purposes, the rapid advances in computed tomography as well as the high radiation doses delivered by interventional procedures have raised serio... The increased use of ionization radiation for diagnostic and therapeutic purposes, the rapid advances in computed tomography as well as the high radiation doses delivered by interventional procedures have raised serious safety and health concerns for both patients and medical staff and have necessitated the establishment of a radiation protection culture(RPC) in every Radiology Department. RPC is a newly introduced concept. The term culture describes the combination of attitudes, beliefs, practices and rules among the professionals, staff and patients regarding to radiation protection. Most of the time, the challenge is to improve rather than to build a RPC. The establishment of a RPC requires continuing education of the staff and professional, effective communication among stakeholders of all levels and implementation of quality assurance programs. The RPC creation is being driven from the highest level. Leadership, professionals and associate societies are recognized to play a vital role in the embedding and promotion of RPC in a Medical Unit. The establishment of a RPC enables the reduction of the radiation dose, enhances radiation risk awareness, minimizes unsafe practices, and improves the quality of a radiation protection program. The purpose of this review paper is to describe the role and highlight the importance of establishing a strong RPC in Radiology Departments with an emphasis on promoting RPC in the Interventional Radiology environment. 展开更多
关键词 RADIATION protection CULTURE RADIATION safety RADIOLOGY DEPARTMENT INTERVENTIONAL RADIOLOGY
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Real-Time Safety Helmet Detection Using Yolov5 at Construction Sites 被引量:2
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作者 Kisaezehra Muhammad Umer Farooq +1 位作者 Muhammad Aslam Bhutto Abdul Karim Kazi 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期911-927,共17页
The construction industry has always remained the economic and social backbone of any country in the world where occupational health and safety(OHS)is of prime importance.Like in other developing countries,this indust... The construction industry has always remained the economic and social backbone of any country in the world where occupational health and safety(OHS)is of prime importance.Like in other developing countries,this industry pays very little,rather negligible attention to OHS practices in Pakistan,resulting in the occurrence of a wide variety of accidents,mishaps,and near-misses every year.One of the major causes of such mishaps is the non-wearing of safety helmets(hard hats)at construction sites where falling objects from a height are unavoid-able.In most cases,this leads to serious brain injuries in people present at the site in general and the workers in particular.It is one of the leading causes of human fatalities at construction sites.In the United States,the Occupational Safety and Health Administration(OSHA)requires construction companies through safety laws to ensure the use of well-defined personal protective equipment(PPE).It has long been a problem to ensure the use of PPE because round-the-clock human monitoring is not possible.However,such monitoring through technological aids or automated tools is very much possible.The present study describes a systema-tic strategy based on deep learning(DL)models built on the You-Only-Look-Once(YOLOV5)architecture that could be used for monitoring workers’hard hats in real-time.It can indicate whether a worker is wearing a hat or not.The proposed system usesfive different models of the YOLOV5,namely YOLOV5n,YOLOv5s,YOLOv5 m,YOLOv5l,and YOLOv5x for object detection with the support of PyTorch,involving 7063 images.The results of the study show that among the DL models,the YOLOV5x has a high performance of 95.8%in terms of the mAP,while the YOLOV5n has the fastest detection speed of 70.4 frames per second(FPS).The proposed model can be successfully used in practice to recognize the hard hat worn by a worker. 展开更多
关键词 Object detection computer-vision personal protective equipment(PPE) deep learning industry revolution(IR)4.0 safety helmet detection
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Grain Protection Potential of Decaleside II, a New Plant-Derived Natural Insecticide
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作者 Yallappa Rajashekar Thimmappa Shivanandappa 《Advances in Entomology》 2014年第3期144-150,共7页
Decaleside II is the novel trisaccharide isolated from the edible roots of Decalepis hamiltonii that belong to a new class of natural insecticides. In the present study we have investigated grain protection potential ... Decaleside II is the novel trisaccharide isolated from the edible roots of Decalepis hamiltonii that belong to a new class of natural insecticides. In the present study we have investigated grain protection potential and persistence activity of Decaleside II against stored-product pests such as Rhyzopertha dominica, Sitophilus oryzae, Tribolium castaneum and Callosobruchus chinensis. Decaleside II usually increased parental mortality and reduced F1 progeny in residual toxicity bioassays. At 7 days of the storage period of treated grains and pulses, the mortality was 100% of all four stored product insects. Both wheat and green gram treated with Decaleside II were totally free from infestation for the longer period of storage up to 210 d. Decaleside II being a natural trisaccharide, does not pose any toxic hazard from the treated grain and the lack of toxicity is attributed to the 1, 4 α linkage of the sugars which are easily hydrolyzed by the digestive enzymes such as glucosidases. Therefore, the insect selectivity and mammalian safety of Decaleside II make them highly suitable for use as novel grain protectants of natural origin. 展开更多
关键词 Decaleside II INSECTICIDAL Activity GRAIN protectants Seed VIABILITY MAMMALIAN safety
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Design of Facial Impact Protection Gear for Cyclists
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作者 Sanga Monthatipkul Pio Iovenitti Igor Sbarski 《Journal of Transportation Technologies》 2012年第3期204-212,共9页
The concept of facial impact protection mask for cyclists is proposed in response to increased participation in cycling and the need for injury prevention. The research aims to develop an approach for design of facial... The concept of facial impact protection mask for cyclists is proposed in response to increased participation in cycling and the need for injury prevention. The research aims to develop an approach for design of facial impact protection gear to reduce the risk of severe injury. Impact test equipment and procedure, face surrogate and protection material performance criteria are developed. Three groups of protective materials – rigid crushable, semi rigid, and soft cushion foams are tested and assessed according to criteria. The criteria are linked to measures of the risk of facial and brain injuries: HIC (Head Injury Criterion), peak deceleration, Face-bone damage and energy absorption. The impact energy is simulated by a drop test using a 48 mm-radius-steel hemispherical impactor, with a weight of 4.63 kg similar to that of headform J specified in AS/NZS standard. The drop-height is 1500 mm, and the linear deceleration force of the impactor is recorded and used to establish the performance of the materials. The HIC is used to predict the risk of brain injury, whereas the developed face surrogate is used to assess facial bone injury. A 5.4 m/s facial impact to the unprotected-face of a cyclist can result in the risk of severe facial bone fracture and mild brain injury. The impact test results for rigid foam protection of 40 mm thickness shows no densification (bottom out) and absorbs the impact energy without damage to the Foam-bone of the face surrogate. At 20 mm thickness, rigid polyurethane foams performed best with Foam-bone damage ranging from 15.1% to 20.5%. Other materials with thicknesses of 20 to 28 mm showed Foam-bone damage between 21.8% and 35.1%. The HIC values ranged from 267 to 522, with memory foams and expanded polystyrene foam having the lowest values. Peak deceleration ranged from 71 g to 105 g for the materials tested. It is concluded that the impact energy can be dissipated by the protection material thereby reducing the risk of severe facial injury to the protected area. 展开更多
关键词 FACIAL IMPACT protection CYCLIST Energy Absorption IMPACT Testing Road safety Injury Prevention
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Occupational Eye Lens Radiation Dose While Performing Interventional Procedures over 18 Months Using a Face-Shield Equipped Suspended Radiation Protection System
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作者 Thomas J. Kwarcinski Andrew Lichliter +3 位作者 Joseph Oros Niraj KC Bryan Yoder Chet R. Rees 《Open Journal of Radiology》 2020年第2期101-114,共14页
<strong>Background: </strong>Numerous studies have demonstrated increasing evidence for cataractogenesis at lower levels of ionizing radiation than previously believed, with some suggesting possible absenc... <strong>Background: </strong>Numerous studies have demonstrated increasing evidence for cataractogenesis at lower levels of ionizing radiation than previously believed, with some suggesting possible absence of a threshold. Genetic differences between individuals also result in increased susceptibility in some operators, who might not be aware. European occupational exposure limits have been reduced and operators are seeking protective measures. <strong>Objective: </strong>To evaluate the protective effect of a face-shield equipped suspended protection system (Zero-Gravity<span style="white-space:nowrap;"><sup><span style="white-space:nowrap;">&reg;</span></sup></span>, TIDI Products, Neenah, WI) along with adherence to safety practices against radiation dose to the eye lens for an interventional radiologist performing a wide variety of procedures. <strong>Materials and Methods:</strong> In this institutional review board-approved single-institution study, one interventional radiologist wore a highly sensitive personnel monitoring dosimeter badge on the cap near the left eye while performing 299 procedures (3690 fluoroscopy minutes) over 18 consecutive months while utilizing the suspended protection system along with adherence to other generally recommended safety practices and movement away from the field during angiographic power injections. Dosimetry reports and procedural information were retrospectively reviewed. <strong>Results: </strong>Total lens dose equivalent to the left eye over 18 months was 0.11 mSv (annualized dose = 0.073 mSv, or 7.3 mRem). The patient-dose-area product standardized dose of 0.00576 <span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&mu;</span></span></span>Sv/Gy<span style="white-space:nowrap;"><span style="white-space:nowrap;">&sdot;</span></span>cm<sup>2</sup> is well below reports of conventional lead aprons, shields, and protective eyewear. <strong>Conclusion: </strong>Eye exposures were kept to near-background levels using the materials and methods of this study while performing a wide variety of complex procedures from all positions around the patient. 展开更多
关键词 Lens Dose Reduction Radiation safety Radiation-Induced Cataractogenesis Suspended protection System
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Establishing a System for Food Recalls to Protect Food Quality and Safety in China
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作者 Liu Wen Wang Jing 《China Standardization》 2007年第6期10-13,共4页
There are no explicit laws concerning food recalls in China; moreover, some related regulations have weaknesses. China should first create a system of laws and regulations governing food recalls, establish a system to... There are no explicit laws concerning food recalls in China; moreover, some related regulations have weaknesses. China should first create a system of laws and regulations governing food recalls, establish a system to recall defective food, and strengthen administrative and legal remedial mechanisms related to consumer rights. 展开更多
关键词 establishment FOOD RECALL system protect FOOD quality FOOD safety
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Investigation on Fire Protection System of Highrise Buildings in the Context of Bir Uttam Aminul Haque Avenue in Dhaka, Bangladesh
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作者 Nazmul Ahmed Roni Sharmin Sultana Mian Md Jawad Ibne Iqbal 《Engineering(科研)》 CAS 2022年第8期301-319,共19页
Rapid high-rise building construction of different occupancies is becoming popular in Dhaka due to its economic gain and functional flexibility. Fire prevention poses a significant difficulty to this type of construct... Rapid high-rise building construction of different occupancies is becoming popular in Dhaka due to its economic gain and functional flexibility. Fire prevention poses a significant difficulty to this type of construction due to its complexity and economic worth as well. Therefore, construction of high-rise building without following the proper fire safety measures, is a common practice at present in the city and it poses a greater threat to urban life considering its associated loss. Even though, most of the owners or authorities do not respect the construction code and the majority of them lack sufficient awareness and basic fire control knowledge and practice. More often, they are unable to comprehend the magnitude and severity of severe fire hazards, and recognize the causes and implementing effective mitigation measures are rare. As a result, the number of fire hazard in high-rise construction is increasing day by day. Hence, investigating the present condition of high-rise buildings (already built) in terms of Fire Protection System is imperative to prevent the upcoming fire hazard. An urban chunk of 33 plots along with Bir Uttam Aminul Haque Avenue, located in Banani, has been chosen for the study area considering its vulnerability to fire hazard. Among these buildings, STAR Tower and HBR Tower, these two high-rise buildings are assessed thoroughly using FRI (Fire Risk Index) Method. The method is semi-quantitative in nature with seventeen parameters associated with fire protection. This assessment represents a scenario in what extent fire codes are being followed in the selected area. It concludes that most of the buildings lack in providing protection against fire hazards for not following the code strictly. This research provides some recommendations which can be followed to improve the fire safety measures in this existing context. It is expected that this research could be a unique addition to firefighting knowledge by contributing to mitigating the consequences of fire related hazards in any densely populated city like Dhaka. 展开更多
关键词 Fire Hazard Fire safety High-Rise Buildings Fire protection Fire Risk Index
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Study on the Lightning-Protection of Ancient Buildings
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作者 樊希彬 熊群峰 夏志刚 《Journal of Landscape Research》 2011年第5期65-69,共5页
By reviewing ancient buildings that were destroyed by lightning strike or fire caused by lightning,lightning protection of ancient buildings was discussed,ancient architectural complex in Dagu Mountain,a provincial-le... By reviewing ancient buildings that were destroyed by lightning strike or fire caused by lightning,lightning protection of ancient buildings was discussed,ancient architectural complex in Dagu Mountain,a provincial-level scenic area of Liaoning,was taken for an example to detect potential safety hazards in lightning-protection of those ancient buildings,5 types of potential safety hazards were summarized.By studying the classification of ancient buildings' lightning-protection,protection level,lightning-protection measures,design basis of lightning-protection engineering,construction and new construction technology,relevant technical specifications were taken as references for proposing 4 countermeasures against those potential safety hazards from the perspectives of exterior and interior parts of ancient buildings,lightning-protection of ancient trees and so on.In view of actual conditions of the ancient architectural complex in Dagu Mountain,construction plan,personnel placement,labor planning,construction quality control system,acceptance of works,technical documentation and such matters were specifically discussed to give useful support to the future lightning-protection of ancient buildings. 展开更多
关键词 ANCIENT BUILDINGS Potential safety hazards in lightning-protection COUNTERMEASURES New construction technology
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Management of the Quality of Corrosion Protection of Structural Steel Based on Corrosion Risk Level
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作者 Volodymyr Korolov Yury Filatov +1 位作者 Natalya Magunova Petro Korolov 《材料科学与工程(中英文B版)》 2013年第11期740-747,共8页
关键词 防腐蚀保护 风险水平 质量管理 结构钢 基础 极限状态设计 防护涂料 管理技术
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复杂环境下秀江双桥控制爆破拆除 被引量:1
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作者 陈颢 谭雪刚 +1 位作者 黄龙华 贺五一 《爆破》 CSCD 北大核心 2024年第1期127-133,共7页
为在复杂环境下对两座200 m钢筋砼桥梁(连续梁老桥与拱形新桥)实施控制爆破,选择双桥桥墩、连续梁腹板及双曲拱桥拱脚为爆破部位,破坏桥梁的主要承重部位。采用深孔桥墩爆破和浅孔主梁爆破相结合的爆破方法,降低施工安全风险并提高施工... 为在复杂环境下对两座200 m钢筋砼桥梁(连续梁老桥与拱形新桥)实施控制爆破,选择双桥桥墩、连续梁腹板及双曲拱桥拱脚为爆破部位,破坏桥梁的主要承重部位。采用深孔桥墩爆破和浅孔主梁爆破相结合的爆破方法,降低施工安全风险并提高施工效率。其中,深孔桥墩爆破采用由桥面向桥墩的大直径垂直炮孔,克服了桥墩圆弧面对最小抵抗线计算的影响,减少了钻孔工作量。设计起爆方式为梁桥同方向逐跨分段延期起爆,即:两桥由南向北同向逐跨起爆,每跨之间等间隔延时,同时两桥之间设计50 ms的延时间隔(新桥的起爆时间比老桥延后50 ms)。为减少爆破振动及塌落振动,采用毫秒延时控制爆破,最小抵抗线方向背离较近岸边保护对象。此外,为控制爆破飞石,采用了桥台堆沙袋,爆破体进行钢丝网捆扎并用多层竹笆覆盖的防护措施。起爆后,大桥逐跨坍塌,被爆桥体塌落解体较充分,塌落振动及飞石控制效果良好。 展开更多
关键词 桥梁拆除 控制爆破 逐跨起爆 安全防护
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鸭短喙侏儒综合征亚单位疫苗安全性及免疫效果评价
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作者 甘辉群 吴双 +3 位作者 傅宏庆 陈光明 孙飞 刘明生 《畜牧与兽医》 CAS 北大核心 2024年第8期70-76,共7页
旨在评价鸭短喙侏儒综合征(SBDS)亚单位疫苗(rBac-JS01 VP2株)的免疫效果。将40只产蛋母鸭和4只成年公鸭随机分成2组,每组产蛋母鸭20只和成年公鸭2只,试验组母鸭经颈背侧皮下注射疫苗0.5 mL,阴性对照组母鸭经颈背侧皮下注射PBS 0.5 mL... 旨在评价鸭短喙侏儒综合征(SBDS)亚单位疫苗(rBac-JS01 VP2株)的免疫效果。将40只产蛋母鸭和4只成年公鸭随机分成2组,每组产蛋母鸭20只和成年公鸭2只,试验组母鸭经颈背侧皮下注射疫苗0.5 mL,阴性对照组母鸭经颈背侧皮下注射PBS 0.5 mL。免疫后2、4和6个月,分别收集各组种鸭鸭蛋并人工孵化,每个阶段任意选择1日龄健康的公、母雏鸭各20只进行SBDS-JS01毒株攻毒,记录攻毒后雏鸭体重和发病情况,并在攻毒后第3、5、7、14、21天采集雏鸭肛拭子检测排毒情况,每组随机剖检2只雏鸭,观察组织病理变化,PCR检测各组病毒分布情况;免疫后2、4、6个月,采集产蛋鸭血液并分离血清,收集鸭蛋并提取、纯化卵黄抗体,采用SBDS-JS01株测定病毒中和抗体效价。结果显示:种鸭免疫后2、4、6个月,所孵雏鸭对SBDS-JS01攻毒保护率分别为100%、95%、90%,观察期各时间段内免疫攻毒组与对照组相比,试验鸭的体重无显著性差异(P>0.05),而非免疫攻毒组试验鸭的体重极显著低于其他各组(P<0.01);雏鸭攻毒后,免疫攻毒组在免疫后2个月所孵雏鸭肛拭子检测均呈阴性,观察期内各时间段组织器官病毒分布均低于非免疫攻毒组;疫苗免疫组在免疫后2、4、6个月血清的SBDSJS01中和抗体效价分别为(10.51±1.59)log_(2)、(9.46±1.27)log_(2)、(8.83±1.15)log_(2),卵黄中和抗体效价分别为(10.12±1.46)log_(2)、(9.37±1.06)log_(2)、(8.49±1.21)log_(2);不同时期的血清中和抗体效价和卵黄中和抗体效价基本一致,升降趋势相同,且与被动免疫攻毒保护水平变化具有很好的相关性。提示:制备的SBDS亚单位疫苗安全性高,免疫效果较好,对SBDS病毒可提供持续有效的保护力。 展开更多
关键词 鸭短喙侏儒综合征 亚单位疫苗 攻毒保护 安全性 免疫效果
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流程生产风险防控的功能安全完整性
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作者 张建荣 张伟 +1 位作者 张充 赵挺生 《科学技术与工程》 北大核心 2024年第9期3923-3929,共7页
为提升流程生产安全管理水平,降低事故发生概率,提出了生产过程中风险防控的功能安全完整性分析方法,并结合钢铁连铸场景进行验证。首先评估流程生产中主要事故类型的危险程度和确定其可接受频率标准;运用保护层分析法计算作业现场高危... 为提升流程生产安全管理水平,降低事故发生概率,提出了生产过程中风险防控的功能安全完整性分析方法,并结合钢铁连铸场景进行验证。首先评估流程生产中主要事故类型的危险程度和确定其可接受频率标准;运用保护层分析法计算作业现场高危险性事故发生的真实概率,通过与可接受频率比较,判断是否需要新增防护措施;运用蒙特卡洛-马尔可夫模型验证新增防护措施的功能安全完整性等级。以大冶特钢炼钢转炉厂连铸作业区为例,结果表明:研究区内存在熔融物爆炸、火灾和中毒窒息3类高危险性事故隐患,且熔融物爆炸事故的人员伤亡后果为不可接受,需新增功能安全完整性等级为2级的防护措施;设计了防爆炸保护系统,其失效概率为4.37×10-3,满足功能安全完整性等级要求。 展开更多
关键词 功能安全 钢铁连铸 安全完整性等级 保护层分析 马尔可夫
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公共安全与保障视角下的应急救援装备工业设计及应用研究综述
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作者 姚君 邵将 +2 位作者 朱金佗 宗威 李轩轩 《包装工程》 CAS 北大核心 2024年第18期1-16,I0006,共17页
目的围绕公共安全与保障视角下的应急救援装备工业设计的理论、方法和案例。综述目前领域内的国内外研究现状和前沿成果,分析装备未来发展与应用前景。方法目前我国产业变革加速、公共安全与保障面临重大挑战,对应急救援装备设计与发展... 目的围绕公共安全与保障视角下的应急救援装备工业设计的理论、方法和案例。综述目前领域内的国内外研究现状和前沿成果,分析装备未来发展与应用前景。方法目前我国产业变革加速、公共安全与保障面临重大挑战,对应急救援装备设计与发展提出了更高要求。本文基于公共安全应急处置情景下“防护”与“救援”两个层面,梳理国内外典型个体防护和应急救援装备的工业设计需求、关键特征和支撑技术。结论针对我国公共安全与保障领域的个体防护与应急急救援装备需求,对比分析了国内外发展现状,梳理了政府政策支持和保障措施,总结了装备工业设计发展面临的机遇与挑战,提出了未来的应用前景,为我国防灾、减灾、救灾和公共安全应急处置的关键保障装备发展建设提供了新方向与新思路。 展开更多
关键词 公共安全 应急救援 工业设计 装备设计 防护装备
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