检索结果-南通市图书馆

Influence of ageing on oil degradation and gassing tendency under high-energy electrical discharge faults for mineral oil and synthetic ester

在线全文

学校读者我要写书评

暂无评论

High Voltage 2020年第6期5卷 731-738页

作者： l.loiselle u.Mohan Rao I.Fofana Research Chair on the Aging of Power Network Infrastructure(ViAHT) Universitédu QuébecàChicoutimiChicoutimiQCG7H 2B1Canada

In this work, mineral oil and synthetic esters were selected at different ageing factors (based on acidity values). Fresh and aged oils have been subjected to high-energy discharges (repeated 100 breakdowns) to simulate electric faults of highly vulnerable intensity. The intent of this work is to understand the influence of high-energy electric faults on oil degradation and gassing tendency at different ageing conditions. In this study, the influence of the high-energy discharges on degradation and gassing tendency at different ageing factors is reported for mineral oil and synthetic esters. Oil degradation is reported by adopting ultraviolet spectroscopy, turbidity and particle counter as per american society for testing and materials (ASTM) standard test methods. Gassing tendencies and fault gas analysis are understood by dissolved the gas analysis using Duval's triangle and Duval's pentagon methods for mineral and non-mineral oils. It is found that the influence of high-energy discharges on oil degradation is higher in mineral oils to that of the synthetic esters. The intensity of the gassing tendency is higher for ester fluids;however, as per the Duval methods, the faulty conditions are at lower levels as compared to mineral oils.

关键词： synthetic energy high

In search of a pan-coronavirus vaccine:next-generation vaccine design and immune mechanisms

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cel.ular & Molecular Immunology 2024年第2期21卷 103-118页

作者： S.Cankat M.u.Demael l.Swadling Division of Infection and Immunity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

Members of the coronaviridae family are endemic to human populations and have caused several epidemics and pandemics in recent *** this review,we will discuss the feasibility of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all members of the coronavirus *** will detail the unmet clinical need associated with the continued transmission of SARS-CoV-2,MERS-CoV and the four seasonal coronaviruses(HCoV-OC43,Nl63,HKu1 and 229E)in humans and the potential for future zoonotic *** will highlight how first-generation SARS-CoV-2 vaccines and natural history studies have greatly increased our understanding of effective antiviral immunity to coronaviruses and have informed next-generation vaccine *** will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of immunity that may offer ***,we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly or universally protective vaccines for coronaviruses.

关键词： Vaccine Coronavirus Cross-reactive immunity Cross-protection universal

Inquiries and Confession before the Cross： An Interpretation of Wang Guilin＇s My Jerusalem

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of literary Studies in China-Selected Publications from Chinese universities 2015年第2期9卷 318-336页

作者： l.u Yan Institute for Trans-cul.ural Studies Beijing Intemational Studies University Beijing 100024China

This essay employs the approach of New Criticism close reading to interpret My Jerusalem by a contemporary Chinese poet, Wang Guilin, from the dialogic perspective of＂I and Thou.＂ From a dimension of faith beyond daily life, the poet narrates his astonishment, historical reflection and spiritual transformation during a visit to Jerusalem. For him, the journey to Jerusalem was also a pilgrimage to a spiritual homeland, self-achievement, and peace and love.

关键词： Jerusalem Bible I and Thou the Cross

Plastic deformation of a Zr-based bulk metallic glass fabricated by selective laser melting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第1期60卷 139-146页

作者： l.Deng K.Kosiba R.limbach l.Wondraczek u.Kühn S.Pauly IFW Dresden Institute for Complex MaterialsHelmholtzstraße 20D-01069DresdenGermany Otto Schott Institute of Materials Research University of JenaFraunhoferstraße 6D-07743JenaGermany university of Applied Sciences Aschaffenburg Würzburger Straße 45D-63743AschaffenburgGermany

Fully amorphous Zr_(52.5)Cu_(17.9)Ni_(14.6)Al_(10)Ti_(5) bulk metallic glass(BMG) samples with a relative density exceeding 98% were fabricated via selective laser melting(SlM).High fracture stresses of around1700 MPa and a reproducible plastic strain of about 0.5% were obtained for cylindrical SlM *** analysis of the observed serrations during compressive loading implies that the shear-band dynamics in the additively manufactured samples distinctly differ from those of the as-cast *** phenomenon appears to originate from the presence of uniformly dispersed spherical pores as well as from the more pronounced heterogeneity of the glass itself as revealed by instrumented *** these heterogeneities,the shear bands are straight and form in the plane of maximum shear *** manufacturing,hence,might not only allow for producing large BMG samples with complex geometries but also for manipulating their deformation behaviour through tailoring porosity and structural heterogeneity.

关键词： Powder bed fusion Selective laser melting Bulk metallic glass Serrated flow Heterogeneity

Teaching and learning Chinese through Immersion:A Case Study from the North American Context

在线全文

学校读者我要写书评

暂无评论

Frontiers of Education in China 2020年第1期15卷 99-141页

作者： Chan lÜ Department of Asian languages&literature University of WashingtonSeattleWA 98195-3521USA

With the promise of achieving bilingualism,biliteracy,and cul.ural pluralism,Chinese immersion programs for students from kindergarten to 12th grade(K-12)in North America,especially the uS,have been proliferating in the past two *** on this rapidly growing population of non-native Chinese learners is also *** research synthesis focuses on 35 selected studies published in recent years on Chinese immersion in both Chinese and English language journals and *** review found that researchers are exploring a wide range of issues with respect to language and literacy development in Chinese immersion programs,including academic achievement in English,language and literacy acquisition in Chinese,instructional strategies and classroom interaction,as well as learners’language use and its sociolinguistic *** studies reflect a growing interest in and demand for learning more about the lesser-researched Chinese foreign language(CFl)learner population,and this review concludes with suggestions for future research on Chinese immersion based on its curricular features as well as specific considerations for conducting research with young,emergent bilingual and biliterate learners.

关键词： K-12 education Chinese immersion programs Chinese as a foreign language(CFl) academic achievement bilingual and biliteracy acquisition instructional strategies classroom interaction learner language

Identification of Hammerstein systems with asymmetric dead-zone nonlinearities using canonical parameterized model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

控制理论与应用（英文版） 2012年第4期10卷 511-516页

作者： Xiaohua lü Xuemei REN School of Automation Beijing Institute of Technology

A non-iterative identification method with parameterization of the unknown dead-zone is proposed for Hammerstein systems in presence of asymmetric dead-zone nonlinearities. The canonical parameterized model which is a single expression without segmentation is utilized to describe the dead-zone, based on which a universal-type parametric model can be established to approximate the entire system. This model can be established without separating the nonlinear part from the linear part. The dead-zone parameters and the coefficients in the linear transfer function can be estimated simultaneously according to the proposed algorithm. Numerical experiments are presented to il.ustrate the effectiveness of the proposed scheme.

关键词： Hammerstein systems Asymmetric dead-zone nonlinearity Canonical parameterized model System identification

Temperature dependence of pressure sensitive flow in bulk metallic glass composites

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第14期181卷 165-175页

作者： Priyanka Saini Yakai Zhao Biao li long Zhang u.Ramamurty R.l.Narayan Department of Materials Science and Engineering Indian Institute of TechnologyDelhi 110016India School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Republic of Singapore Institute of Materials Research and Engineering Agency for ScienceTechnology and Research138634Republic of Singapore Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The constraint factor,C,defined as hardness,H,to the yield strength,σ_(y),ratio,is an indirect measure of the pressure sensitivity in *** investigations determined that while C is less than 3 for crystalline materials,and remains invariant with change in temperature,it is greater than 3 for bulk metallic glasses(BMGs)and increases with increasing temperature,below their glass transition temper-ature,T_(g).In this study,the variations in C for two BMG composites(BMGCs),which have an amorphous matrix and in situ precipitated crystallineβ-Ti dendrites,which in one case transforms under stress toα”-Ti and deforms by slip in the other,as a function of temperature are examined and compared with that of a *** this purpose,instrumented indentation tests,with a Berkovich tip,and uniaxial com-pression tests were performed to measure the H andσ_(y),respectively,on all alloys and their constituents at temperatures in the range of 0.48 T_(g) and 0.75 T_(g).σ_(y) and H of the BMGC with transforming dendrites(BMGC-T)increase and remain invariant with increasing temperature,***,in BMG and the BMGC with non-transforming dendrites(BMGC–NT),the same properties decrease with increas-ing ***-T has the highest C of∼4.93 whereas that of BMGC–NT and BMG are∼3.72 and∼3.28,respectively,at 0.48 T_(g).With increasing temperature,C of the BMG and BMGC–NT increases with temperature,but that of the BMGC-T *** values of C and their variations as a function of temperature were explained by studying the variation of pressure sensitivity of the amorphous phase and concluding that the plastic flow in BMGCs under constrained conditions,such as indentation,is con-trolled by the flow resistance of the amorphous matrix whereas that in uniaxial compression,which is only partially constrained,is controlled by plasticity in both the dendrites and matrix.

关键词： Bulk metallic glass composites Hardness Pressure sensitivity Martensitic transformation

Sustainable graywater reuse for residential landscape irrigation-a critical review

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Population,Resources and Environment 2015年第3期13卷 250-264页

作者： u.Pinto B.l.Maheshwari School of Science & Health University of Western Sydney

The demand for potable water is rising rapidly due to an ever-increasing population,economic activities,and dwindling water *** provide adequate water supplies in the future,understanding the issues and challenges in the reuse of water and developing appropriate strategies for reuse will be *** way to augment water supplies for residential.use is to reuse graywater- the wastewater from kitchens,bathrooms,and *** this article,we critically review the evolution of water reuse,the definition of graywater,graywater reuse practices,volumes and flow in different situations,and graywater *** then examine the issues associated with different graywater treatment methods and how using graywater for irrigation around homes affects soil quality and plant *** study concludes that graywater treatment costs,human health risks,and its effect on soil quality are some of the challenges that need to be addressed in the future for widespread and sustainable reuse of graywater for irrigation around homes.

关键词： water reuse graywater irrigation sustainability urban water water treatment

luminescence investigation of Dy2O2S and Dy2O2SO4 obtained by thermal decomposition of sulfate hydrate

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2016年第8期34卷 814-819页

作者： R.V.Rodngues l.Marciniak l.u.Khan J.R.Matos H.F.Brito W.Strek Institute of Chemistry University of Sao Paulo Butanta 748 26077 Sao Paulo Brasil Institute of low Temperature and Structure Research University of Wroctaw Oko1na 250-422 Wroclaw Poland

The yellow emitting dysprosium oxysulfide （Dy2O2S） and dysprosium oxysulfate （Dy202SO4） compounds were prepared from the thermal decomposition of hydrated dysprosium sulphate. The materials were characterized by using thermogravimetry （TG/DTG）, X-ray powder diffraction （XRD）, Fourier transform infrared （FTIR） and Raman spectroscopies. The thermal stability temperatures at around 1151 and 1313 K were determined for the Dy202S and Dy202SO4 materials, respectively. The photolumines- cence properties of the dysprosium oxysulfide were investigated, showing narrow emission bands assigned to the 4F9/2----＊6HJ intracon- figurational transitions of the Dy3＋ ion. The yellow emission color of this phosphor suggests that the Dy202S is a promising material for applications in lEDs.

关键词： Dy202S/Dy202SO4 sulfate thermal decomposition luminescence rare earths