检索结果-南通市图书馆

Study on preparation and electromagnetic shielding properties of silver-coated ferrosilicochrome powder

Chinese j.urnal of Ship Research 2024年第2期19卷 173-180页

作者： Wu j. Wang W. Yang X. Deng L. Chen Q. School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China China Ship Development and Design Center Wuhan 430064 China

［Obj.ctive］This study focuses on the preparation and properties of high-performance electromagnetic shielding materials for electronic equipment in marine environments. ［Methods］The surface morphology, phase composition, electrical conductivity and ferromagnetic properties of the original ferrosilicochrome powder (FeSiCr) and silver-coated powder (FeSiCr@Ag) are analyzed with a scanning electron microscope, X-ray diffractometer, four probes and vibrating sample magnetometer, and a vector network analyzer is used to test the S parameters of the samples. A salt spray test chamber is used to simulate the corrosion behavi- or of the coating under marine environment conditions and observe its macro and micro morphology. Meanwhile, an electrochemical workstation is used to monitor the corrosion behavior of the coating in a mass fraction of 3.5% NaCl solution and study its corrosion mechanism. ［Results］The results show that the silver plating layer is compact and complete with the increase of the silver nitrate (AgNO3) addition. After electroless silver plating, the conductivity can reach 586.79 S/cm and the X-band shielding efficiency reaches 80 dB. After 96 h of accelerated corrosion in a humid heat and high salt spray environment, the surface of the resin coating prepared by FeSiCr@Ag shows no corrosion phenomenon. The self-corrosion potential of the coating before and after electroless silver plating is −0.4 V and −0.09 V respectively, indicating that the penetration rate of the corrosive medium into the coating slows down after silver plating, and a good corrosion inhibition effect is achieved.［Conclusions］The modified FeSiCr@Ag material has highly efficient electromagnetic shielding performance and good corrosion resistance properties. © 2024 Editorial Department of Chinese j.urnal of Ship Research. All rights reserved.

关键词： coating modification corrosion resistance electromagnetic shielding ferrosilicochrome

来源：博看期刊评论

在线全文

博看期刊

学校读者我要写书评

暂无评论

Effect of carbonation on the properties of granite-bearing oxysulfate oxide cement

引用

Chongqing Daxue Xuebao/j.urnal of Chongqing University 2024年第6期47卷 35-42页

作者： j.n K. Zhang X. Bi W. Wang D. Han j. School of Civil & Water Conservancy Engineering Ningxia University Yinchuan 750021 China College of Materials and Metallurgy University of Science and Technology Liaoning Anshan 114051 China Water Resources Engineering Research Center in Modern Agriculture in Arid Regions Ningxia University Yinchuan 750021 China Ningxia Center for Research on Earthquake Protection and Disaster Mitigation in Civil Engineering Ningxia University Yinchuan 750021 China Engineering Technology Research Center of Water-Saving and Water Resource Regulation Ningxia University Yinchuan 750021 China School of Civil Engineering North Minzu University Yinchuan 750030 China

The properties of magnesium oxysulfate (MOS) cement with different granite powder (GP) contents with CO2 curing were studied. The hydration products and microstructure of MOS cement were analyzed using X-ray diffraction (XRD), simultaneous comprehensive thermal analyzer (TG-DSC), scanning electron microscope (SEM) and mercury porosimeter (MIP). The results shows that the strength retention coefficient of MOS cement containing 40% GP reached 1.12 with standard curing for 28 days followed by 28 days of CO2 curing; when MOS cement was CO2-cured for 28 days and then immersed in water for 120 days, the strength retention coefficient reached 0.94, which was 123.8% higher than that of blank samples. MgCO3·zH2O crystals were generated after MOS cement underwent CO2 curing, which had a positive effect on the mechanical properties and water resistance by reducing matrix expansion caused by MgO hydrating to Mg(OH)2. GP increased the matrix density, reduced the CO2 capture rate, and decreased CO2 erosion of MOS cement by optimizing the pore structure. The presence of GP and magnesium carbonate phases improved the compressive strength of MOS cement after carbonation and immersion. © 2024 Chongqing University. All rights reserved.

关键词： carbonation magnesium carbonate magnesium oxysulfate cement water resistance

来源：博看期刊评论

在线全文

博看期刊

学校读者我要写书评

暂无评论

Degradation and resynthesis of chlorophyll during increased oxidative stress and prolonged darkness differ between annual and perennial flax(Linum L.)

引用

Oil Crop Science 2024年第2期9卷 121-130页

作者： Kenyon j. Nisbett Abida Alokozai Su Hyun Elizabeth Ko G. Adam Mott j.son C.L. Browna Department of Biological Sciences University of Toronto ScarboroughTorontoONCanada Department of Cell&Systems Biology University of TorontoTorontoONCanada Centre for the Analysis of Genome Evolution&Function University of TorontoTorontoONCanada

Among plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the longest-living perennial having survived 43,600 years.As proposed by the Disposable Soma Theory,this lifespan variation among plants likely reflects differential investment of limited energy and nutrient resources,with perennials investing more energy and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple seasons.Such differential investment may be particularly important during periods of exogenous stress,which are known to accelerate biomolecular damage.The present study evaluated this hypothesis using annual and perennial flax(Linum L.)subj.cted to two exogenous stressors—increased oxidative stress(i.e.,foliar H2O2spraying)and complete prolonged darkness.As chlorophyll has been shown to exhibit degradation in response to changes in environmental conditions,we utilized changes in chlorophyll levels during and after periods of exogenous stress to evaluate our hypotheses.We predicted that i)perennials would exhibit a slower rate of chlorophyll degradation during exposure to exogenous stressors compared to annuals,and ii)perennials would exhibit a faster rate of chlorophyll resynthesis following such exposure compared to annuals.Chlorophyll levels before,during,and after exposure to both exogenous stressors were measured in two separate trails,once using image colour analysis and once using spectrophotometry.While chlorophyll degradation rates in response to oxidative stress did not differ between annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates following such exposure were significantly higher in perennials,as predicted.When plants were subj.cted to complete prolonged darkness,chlorophyll degradation rates were significantly lower in perennials than annuals,as predicted;however,when plants were subsequently reintroduced to natural photoperiod,chlorophyll resynthesis rates did not consistently

关键词： Ageing Life history Maximum lifespan Oxidative stress Somatic maintenance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Oral Health Status of Person with Special Needs in Kumasi

引用

Open j.urnal of Stomatology 2024年第1期14卷 14-31页

作者： Ama Agyeibea Amuasi Alexander Oti-Acheampong Victoria N. A. Boadu Lord j. j. Gowans The Department Child Oral Health & Orthodontics School of Medicine and Dentistry College of Health Sciences Kwame Nkrumah University of Science and Technology Kumasi Ghana The Department of Oral & Maxillofacial Sciences School of Medicine and Dentistry College of Health Sciences Kwame Nkrumah University of Science and Technology Kumasi Ghana The Department of Community Dentistry School of Medicine and Dentistry College of Health Sciences Kwame Nkrumah University of Science and Technology Kumasi Ghana

background: The most prevalent non-communicable disease worldwide is oral health-related disease, with dental caries and periodontal conditions being common. Oral health status significantly impacts overall health and quality of life. Barriers to dental care affect children with special needs. This study evaluates the oral health status and treatment requirements of people with special needs. Methodology: This descriptive cross-sectional study in Kumasi, Ghana examined oral health status among people, 121 children with special needs over two months, in j.ne-j.ly 2022. Dental caries, periodontal changes, malocclusion, and trauma were assessed. The data was analyzed using SPSS 20.0. Results: The oral health status among people with special needs in this study was generally moderate, with a range from very good to very poor. The prevalence of dental caries was 37%, with a mean DMFT score of 2.82. Periodontal health showed unsatisfactory indicators such as mobile teeth, poor gingival health, high plaque scores, and the presence of halitosis. Conclusion: This descriptive study aimed to provide baseline data on the oral health status of special needs students in Kumasi, addressing the lack of knowledge in this area. It highlighted the importance of dental care in maintaining good oral health and overall well-being in individuals with special needs. Coordinated efforts by dental professionals are needed to provide dental health education and preventive interventions for these children.

关键词： Special Needs Oral Health Dental Caries Periodontal Diseases Malocclusion

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Necrotic enteritis and antibiotic-free production of broiler chickens:Challenges in testing and using alternative products

引用

Animal Nutrition 2024年第1期16卷 288-298页

作者： Robert j.Moore School of Science RMIT University

The global trend towards raising broiler chickens without the use of in-feed antibiotics(IFAs) means that there is an ongoing need to develop alternative treatments capable of delivering the benefits that IFAs previously provided. IFAs supported the productivity performance of chickens and played a key role in maintaining their health. Necrotic enteritis(NE) is an important disease of broilers that affects health,productivity, and welfare, and was previously well controlled by IFAs. However, with the reduction in IFA use, NE is resurgent in some countries. Vaccines and various feed additives, including pre-, pro-, and postbiotics, phytobiotics, fatty acids, and phage therapies have been introduced as alternative methods of NE control. While some of these feed additives have specific activity against the NE pathogen, Clostridium perfringens, most have the more general goal of reinforcing gut health. Extensive reviews of the effects of many of these feed additives on gut health have been published recently. Hence, rather than cover previously well reviewed areas of research this review focuses on the challenges and pitfalls in undertaking experimental assessment of alternative NE treatments and translating laboratory research to real world commercial production settings. The review is based on the author's particular experience,reading, thoughts, and analysis of the available information and inevitably presents a particular understanding that is likely to be at odds with others thinking on these issues. It is put forward to stimulate thinking and discussion on the issues covered.

关键词： Necrotic enteritis

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

德国历史哲学传统中的理念论及其批判

引用

世界哲学 2024年第4期 54-62页

作者：尉佩云 [德]j.吕森山西大学历史文化学院埃森高等人文研究所

在德国的学术传统中,历史哲学具有漫长的学术历程,它伴随着历史学职业化的过程而形成、发展。在初创及此后的语境中,它成为一种思考过去的全新的学术领域和学术形式。在德国历史哲学开端之处,理念论便主导了这个思想传统,这种影响一直... 详细信息

在德国的学术传统中,历史哲学具有漫长的学术历程,它伴随着历史学职业化的过程而形成、发展。在初创及此后的语境中,它成为一种思考过去的全新的学术领域和学术形式。在德国历史哲学开端之处,理念论便主导了这个思想传统,这种影响一直延续至今。我们可以从四个方面来审视理念论在德国历史哲学中的影响,以启蒙运动之后的德国历史哲学演变的四个先后相序的阶段或形式为题,这分别是理念论的历史哲学,理念论的历史方法论,理念论的历史认识论和理念论视角下诗性与修辞的历史书写。在今天,理念论失去了在方法论上的合理性,但如果历史学还是建立在人类生活形式的解释学基础之上的学科,那么理念论的学术思考就仍然有必要进行批判性反思。将人类受难等现实主义思考纳入其中,在我们将这种现实主义进行人文化的时候,理念论在当下语境中应该获得进一步批判性思考。

关键词：理念论历史哲学史学职业化历史认识论诗性史学

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Full Dynamic Model for Liquid Sloshing Simulation in Cylindrical Tank Shape

引用

World j.urnal of Mechanics 2024年第4期14卷 55-72页

作者： Omar Noui Mohamed Bouazara Marc j. Richard Department of Applied Science University of Quebec at Chicoutimi Chicoutimi Canada Department of Mechanical Engineering Laval University Quebec Canada

This study presents a comprehensive full dynamic model designed for simulating liquid sloshing behavior within cylindrical tank structures. The model employs a discretization approach, representing the liquid as a network of interconnected spring-damper-mass systems. Key aspects include the adaptation of liquid discretization techniques to cylindrical lateral cross-sections and the calculation of stiffness and damping coefficients. External forces, simulating various vehicle maneuvers, are also integrated into the model. The resulting system of equations is solved using Maple Software with the Runge-Kutta-Fehlberg method. This model enables accurate prediction of liquid displacement and pressure forces, offering valuable insights for tank design and fluid dynamics applications. Ongoing refinement aims to broaden its applicability across different liquid types and tank geometries.

关键词： Fluid-Structure Interaction Equivalent Mechanical Model Liquid Discretization Spring-Mass Model Spring-Mass Network Liquid Simulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

RETRACTED: Nuclear Structure Study of Odd-Odd Yttrium Nuclei within Interacting-Boson Fermi-Fermion Model (IBFFM)

引用

j.urnal of Applied Mathematics and Physics 2024年第6期12卷 2020-2031页

作者： Afrah j. Mohaisen Saad N. Abood Physics Department College of Science Al-Nahrain University Baghdad Iraq

Short Retraction NoticeThe paper does not meet the standards of "j.urnal of Applied Mathematics and Physics". This article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused.Editor guiding this retraction: Prof. Wen-Xiu Ma (EiC of j.MP)The full retraction notice in PDF is preceding the original paper, which is marked "RETRACTED".

关键词： Nuclear Structure Yttrium Nuclei Interacting Boson-Fermion Model Energy Spectra Electromagnetic Transition Rates

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Evaluating Methods of Visual Assistance for Workers to Improve Quality and Usability in Individualized Kitchen Cabinet Assembly

引用

j.urnal of Computer and Communications 2024年第2期12卷 156-172页

作者： Albert Eff Michael S. j. Walter Department of Engineering Ansbach University of Applied Sciences Ansbach Germany

In times of digitalisation, visual assistance systems in assembly are increasingly important. The design of these assembly systems needs to be highly complex to meet the requirements. Due to the increasing number of variants in production processes, as well as shorter innovation and product life cycles, assistance systems should improve quality and reduce complexity of assembly processes. However, many large kitchen manufacturers still assemble kitchen cabinets manually, due to the high variety of components, such as rails and fittings. This paper focuses on the analysis and evaluation of virtual assistance systems to improve quality and usability in individualised kitchen cabinet assembly processes at a large German manufacturer. A solution is identified and detailed.

关键词： Digitalisation Assembly Process Visual Assistance Usability Human-Centred Assembly Design

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Buechel Pappas Resurfacing Shoulder Replacement: Evolution and over 40 Years of Clinical Experience

引用

Open j.urnal of Orthopedics 2024年第5期14卷 218-228页

作者： Frederick F. Buechel Michael j. Pappas Rutgers Nj.Medical School Newark NJ USA South Mountain Orthopaedic Associates South Orange NJ USA New j.rsey Institute of Technology Newark NJ USA

background: Early exploration of the semi constrained “Floating-Socket” total shoulder replacement (TSR) in 1974 led to a proliferation of various unconstrained designs that allowed resection or retention of the humeral head, depending upon the pathological process involved. Degenerative glenohumeral arthritis with mild to moderate involvement of subchondral bone allowed for a resurfacing option, while severe humeral head involvement required a partial or full humeral head replacement attached to an intramedullary stem for fixation. All components evolved from cemented to cementless application by 1982. The purpose of this paper is to describe the progression of Buechel-Pappas (B-P) shoulder replacement development from the early 1970’s in both cemented and cement less applications. Methods: Clinical evaluations of “Floating-Socket” TSR, followed by B-P stem-type, resurfacing types, bipolar-type and revision components, all of which comprise the B-P Shoulder Replacement System, were performed over a 49-year period. Results: “Floating-Socket” implants improved the results of simple, constrained ball-in-socket designs, but generally failed by glenoid component loosening in both chimpanzee and human applications. Unconstrained resurfacing-type components, both anatomical humeral head and full proximal humeral components, were quite successful, with minimal failures observed in long-term studies. Bipolar salvage implants, used for severe proximal deficiencies, revisions and massive rotator cuff arthropathy, were also very successful;providing overhead range of motion in many patients. Conclusions: Resurfacing hemiarthroplasty, in patients with intact or repairable rotator cuff mechanisms, gave the most satisfactory results and were the least technically complicated to perform, requiring minimal instrumentation. Resurfacing of full proximal humeral deficiencies, using femoral resurfacing components, gave similar clinical results to more complex semi-constrained devices, also with less technical difficulties and simple

关键词： Total Shoulder Replacement Resurfacing Shoulder Replacement

来源：

维普期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：