检索结果-南通市图书馆

Information Processing in Agriculture 2014年第1期1卷 34-41页

作者： M.f.Hossain Yu Zhang w.Chen American International University-Bangladesh Kamal Ataturk AvenueBananiDhaka 1213Bangladesh Canada Center for Mapping and Earth Observation Natural Resources Canada560 Rochester StreetOttawaON K1S 4M2Canada

Canada’s Arctic and sub-arctic consist 46%of Canada’s landmass and contain 45%of the total soil organic carbon(SOC).Pronounced climate warming and increasing human disturbances could induce the release of this SOC to the atmosphere as greenhouse *** is committed to estimating and reporting the greenhouse gases emissions and removals induced by land use change in the Arctic and *** assess the uncertainty of the estimate,we compiled a site-measured SOC database for Canada’s north,and used it to compare with a polygon database,that will be used for estimating SOC for the UNfCCC *** 10 polygons where 3 or more measured sites were well located in each polygon,the site-averaged SOC content agreed with the polygon data within±33%for the top 30 cm and within±50%for the top 1 m *** we directly compared the SOC of the 382 measured sites with the polygon mean SOC,there was poor agreement:The relative error was less than 50%at 40%of the sites,and less than 100%at 68%of the *** relative errors were more than 400%at 10%of the *** comparisons indicate that the polygon database is too coarse to represent the SOC conditions for individual *** difference is close to the uncertainty range for *** spatial database could be improved by relating site and polygon SOC data with more easily observable surface features that can be identified and derived from remote sensing imagery.

关键词： Arctic and sub-arctic SOC Uncertainty analysis

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foreword

Journal of Materials Science & Technology 2014年第6期30卷 I0001-I0002页

作者： w.H.wang Z.f.Zhang Institute of Physics Chinese Academy of Sciences at Beijing

As a new class of advanced materials, metallic glasses （also often referred as amorphous alloys） possess a combination of unique amorphous structure and remarkably impressive mechanical and physical properties, and are now at the cutting edge of research. The emergence of bulk metallic glasses （BMGs） provides more alloy compositions, large geometric size and diverse mechanical behaviors for some fundamental issues such as deformation and fracture mechanisms of glassy materials and potentiates possibly great applications. In particular, the BMG-s exhibit many unique mechanical properties, such as superior strength and hardness, excellent scratch and wear resistance, extremely high elastic limit, and diverse fracture toughness （varying significantly from approaching ideal brittleness like the oxide glasses for Mg-based BMGs to the highest known damage tolerance for Pd-based BMGs） and patterns （such as dimple structures, nanoscale periodic corrugations, and fiver patterns）. It has become possible to experimentally characterize the mechanical behaviors of metallic glasses and to explore their correlations with the processing conditions, structures and other properties, and accordingly in a more general sense, to understand the deformation, energy dissipation, and fracture mechanisms in the disordered glassy materials. The important and interesting mechanical properties and deformation mechanisms are currently the focus of intense research in the material science community, and the corresponding studies on them are progressing at a fast pace.

关键词： BMGs foreword

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图书馆馆员职务,职业特性,和社会变革

新世纪图书馆 1983年第1期 78-83页

作者： w.f.倍得沙尔王通南京工学院图书馆

本文系从美国图书馆杂志《Library Tournal No.2 1982》译出。按该刊创办于1876年,与美国图书馆学会(ALA)同年成立的美国专业性刊物。文中主要论点,通过对美国社会的发展,尤其对美国科学技术的发展,做为一个图书馆管理人员所肩负的重大... 详细信息

本文系从美国图书馆杂志《Library Tournal No.2 1982》译出。按该刊创办于1876年,与美国图书馆学会(ALA)同年成立的美国专业性刊物。文中主要论点,通过对美国社会的发展,尤其对美国科学技术的发展,做为一个图书馆管理人员所肩负的重大职责。我们知道,美国图书馆工作三大重点—藏书、管理、服务都已实行电脑化。它们图书馆从业人员,也都已全部专业化,美国图书馆制度的现代化=过去成就+现代技术+对未来构思。本文中就着重指出美国社会上一些专家学者,对未来美国图书馆事业的一些远景瞻望。时代形势要求,作为一个图书馆工作人员,应力求做到一专多能。才能胜任本职工作,适应社会变革中不断呈现出来的新要求,新任务!

关键词：社会变革图书馆管理人员图书馆工作人员图书馆员情报信息职业特性专家读者预言家美国美利坚合众国北美洲知识垄断职务情报部门图书馆学会情报服务情报工作

Bulk density of mineral and organic soils in the Canada’s arctic and sub-arctic

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Information Processing in Agriculture 2015年第3期2卷 183-190页

作者： M.f.Hossain w.Chen Yu Zhang American International University-Bangladesh Kemal Ataturk AvenueH 58/BR 21BananiDhaka 1213Bangladesh Canada Center for Mapping and Earth Observation Natural Resources Canada560 Rochester StreetOttawaON K1S 4M2Canada

Bulk density is an indicator of soil compaction subject to anthropogenic impact,essential to the interpretation of any nutrient budgets,especially to perform carbon *** is so expensive to measure bulk density in arctic/sub-arctic and there are relatively very few.f.eld measurements are ***,to establish a bulk density and SOC empirical relationship in Canada’s arctic and sub-arctic ecosystems,compiled all the bulk density and SOC measurements that are available in Northern *** addition an attempt has been made for bulk density and SOC field measurement in Yellowknife and Lupin,to develop an empirical relationship for Canada’s arctic and *** between bulk density(BD)and soil organic carbon(SOC)for mineral soil and organic soils(0–100 cm depth)were described by exponential *** best fit model,predictive bulk density(BDp),for mineral soil,(BDp=0.701+0.952 exp(0.29 SOC),n=702,R2=0.99);for organic soil(BDp=0.074+2.632 exp(0.076 SOC),n=674,R2=0.93).Different soil horizons have different bulk densities and may require different predictive equations,therefore,developed predictive best fit exponential equation for both mineral and organic soils together(BDp=0.071+1.322 exp(0.071 SOC),n=1376,R2=0.984),where X is a dummy variable with a value of 0 for surface peat(0–25 cm depth)and 1 for subsurface peat(25–175 cm).we recommend using the soil organic carbon density approach to estimate BD from SOC because it allows BD to be predicted without significant bias.

关键词： Bulk density Mineral and organic soils Canada’s arctic and sub-arctic

Reviewing the Chinese-Specific Reference Amounts Study Conducted by Sun et al.,2022

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China CDC weekly 2023年第34期5卷 763-765页

作者： w.Marty Blom Joost westerhout Geert f.Houben Department RAPID The Netherlands Organisation for Applied Scientific Research(TNO)Utrechtthe Netherlands.

The need for region-specific food intake values to accurately estimate food allergen risk is underscored by the recent Ad Hoc Joint food and Agriculture Organization/world Health Organization(fAO/wHO)Expert Consultation on Risk Assessment of food Allergens(1).A recent study published by Sun et *** China CDC weekly 2022,titled A Chinese-Specific Reference Amounts Study with TNO food Allergen Risk Assessment Models—China,2022,critically examines and applies a previously established sensitivity analysis aimed at deriving food intake values for food allergen risk assessment(RA)(2–3).In their examination of Chinese food consumption data,the authors find that“the 95th–99th percentiles of the food consumption distribution per eating occasion for condiments and chocolates are the optimal point estimates for use in deterministic allergen RA,aiming to protect 99%of allergic individuals from allergic reactions due to unintended peanut presence.”

关键词： al. intake allergic

Gas Quenching during Age Hardening of the Aluminium Casting Alloy Al-7Si-0.3Mg

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材料热处理学报 2004年第5期25卷 498-501页

作者： A. Rose O. Kessler f. Hoffmann H.w. Zoch Stiftung Institutfttr werkstofftechnik Bremen GermanyStiftung Institutfttr Werkstofftechnik Bremen GermanyStiftung Institutfttr Werkstofftechnik Bremen GermanyStiftung Institutfttr Werkstofftechnik Bremen Germany

for quenching of age hardenable aluminium alloys today predominantly aqueous quenching media are used, which can lead due to the Leidenfrost phenomenon to a non-uniform cooling of the parts and thus to thermal stresses. Particularly at thin-walled or complex shaped parts local plastic deformations can occur by the uneven thermal stresses. In relation to the conventional quenching procedures in aqueous media, gas quenching exhibits a number of technological, ecological and economical advantages. In comparison to liquid quenching media, gas does not change its phase during quenching. Moreover, the cleaning problem of the parts can be avoided. The quenching intensity can be adjusted by the variable parameters gas pressure and gas speed as well as the kind of gas and thus can be adapted to the requirements of the alloy. By the higher uniformity and the better reproducibility, gas quenching offers a high potential to reduce distortion. The goal of these investigations is to clarify, if the cooling rate during gas quenching is sufficient to obtain the specific required strength after age hardening of the alloy Al-7Si-0.3Mg. for this purpose different tests in high-pressure gas quenching facilities, gas nozzle fields and water quenching baths were performed.

关键词：气体流淬火铝合金 Al-7Si-0.3Mg 沉淀硬化机械性质

Role and regulation of the forkhead transcription factors fOXO3a and fOXM1 in carcinogenesis and drug resistance

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Chinese Journal of Cancer 2013年第7期32卷 365-370页

作者： Ana R.Gomes fung Zhao Eric w.f.Lam Department of Surgery and Cancer Imperial College LondonHammersmith Hospital Campus

The fOXO3a and fOXM1 forkhead transcription factors are key players in cancer initiation,progression,and drug *** research shows that fOXM1 is a direct transcriptional target of fOXO3a,a vital downstream effector of the PI3K-AKT-fOXO signaling *** addition,fOXM1 and fOXO3a also antagonize each other's activity by competitively binding to the same target genes,which are involved in chemotherapeutic drug sensitivity and *** the role and regulation of the fOXO-fOXM1 axis will provide insight into chemotherapeutic drug action and resistance in patients,and help to identify novel therapeutic approaches as well as diagnostic and predictive biomarkers.

关键词：转录因子耐药性叉头致癌性化疗药物生物标志物竞争力敏感性

THEORETICAL STUDY Of HEAT TRANSfER ENHANCEMENT IN PIPE wITH POROUS BODY

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Journal of Hydrodynamics 2001年第1期13卷 111-116页

作者： Gong, w.P. Han, J.T. Cheng, f. Dep. of Power Eng. Shandong Univ. Jinan 250061 China

A theoretical investigation on the fluid flow and heat transfer in a pipe with porous body of high porosity twisted by metal wire was carried out. A theoretical model of a circular pipe with porous matrix attached at the channel wall and extended inward the centerline was set up. Through analyzing the flow in the porous matrix by the Brinkman-extended-Darcy equation and through including the effect of dispersion by adding the dispersion coefficient into the energy equation, the theoretical solutions of velocity distribution and temperature fields were obtained. finally the effect of the properties of the porous matrix on the flow and heat transfer in the porous body was studied, which indicates that dispersion can really enhance the heat transfer in pipe.

关键词： Computer simulation Dispersions Mathematical models Pipe flow Porosity Porous materials

Design and commissioning of a semi-confined blast chamber

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Defence Technology（防务技术） 2016年第2期12卷 147-158页

作者： I.M.SNYMAN f.J.MOSTERT w.GRUNDLING defence peacesafety and securitycouncil for scientific and industrial researchMeiring Naude RoadPretoriaSouth Ajkica

This paper presents the design, test and analysis of a scaled cylindrical blast chamber. The blast chamber is a one-fifth dimensional size replica of the full-scale blast chamber(Emily). The blast chamber is semi-confined as one end is open. The scaled blast chamber is used to test concepts for closing the open end and allows the gas to vent at the same time. ANSYS AUTODYN calculated the pressure time histories for different closure scenarios. Comparing the results suggested a viable scenario, namely a structure consisting of a circular disc and a frame positioned at the open end of the blast chamber. The structure and cylindrical blast chamber were subjected to scaled blast tests and the pressure results are presented and discussed.

关键词：设计鼓风室压力时间曲线爆炸试验调试密闭结构组成 ANSYS

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污水处理能耗与能效