检索结果-南通市图书馆

Recovery of.rare and precious metals f.om urban mines —— A review

f.ontiers of.Environmental Science & Engineering 2017年第5期11卷 3-19页

作者： Mengmeng Wang Quanyin Tan joseph f. chiang Jinhui Li Key Laboratory f.r Solid Waste Management and Environment Saf.ty (Tsinghua University) Ministry of Education of China School of Environment Tsinghua University Beijing 100084 China Department of.Chemistry and Biochemistry State University of New York College at Oneonta Oneonta NY 13820 USA

Urban mining is essential f.r continued natural resource extraction. The recovery of.rare and precious metals （RPMs） f.om urban mines has attracted increasing attention f.om both academic and industrial sectors, because of.the broad application and high price of.RPMs, and their low content in natural ores. This study summarizes the distribution characteristics of.various RPMs in urban mines, and the advantages and shortcomings of.various technologies f.r RPM recovery f.om urban mines, including both conventional （pyrometallurgical, hydrometallurgical, and biometallurgical processing）, and emerging （electrochemical, supereritieal f.uid, mechanochemical, and ionic liquids processing） technologies. Mechanical/physical technologies are commonly employed to separate RPMs f.om nonmetallic components in a pre-treatment process. A pyrometallurgical process is of.en used tbr RPM recovery, although the expensive equipment required has limited its use in small and medium-sized enterprises. Hydrometallurgical processing is ef.ective and easy to operate, with high selectivity of.target metals and high recovery ef.iciency of.RPMs, compared to pyrometallurgy. Biometallurgy, though, has shown the most promise f.r leaching RPMs f.om urban mines, because of.its low cost and environmental f.iendliness. Newly developed technologies electrochemical, supercritical f.uid, ionic liquid, and mechanochemical have of.ered new choices and achieved some success in laboratory experiments, especially as ef.icient and environmentally f.iendly methods of.recycling RPMs. With continuing advances in science and technology, more technologies will no doubt be developed in this f.eld, and be able to contribute to the sustainability of.RPM mining.

关键词： Rare and precious metals (RPMs) Distribution characteristics Recycling technology Emerging technology Supercritical f.uid

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

Nanoseparation-lnspired Manipulation of.the Synthesis of.CdS Nanorods

引用

Nano Research 2011年第2期4卷 226-232页

作者： Xiaoming Sun Xiuju Ma Lu Bai Junf.ng Liu Zheng Chang David G. Evans Xue Duan Jiaou Wang joseph f. chiang State Key Laboratory of.Chemical Resource Engineering RO. Box 98 Beijing University of Chemical Technology Beijing 100029 China Institute of.High Energy Physics Beijing 100039 China Department of.Chemistry and Biochemistry SUNY-Oneonta Oneonta NY 13820 USA

CdS nanorods have been sorted by length using a density gradient ultracentrif.ge rate separation method. The f.actions containing longer rods showed relatively stronger oxygen-related surf.ce trap emission, while the shorter ones had dominant band-edge emission. These results suggest that the f.nal length distribution of.CdS nanorods is not a result of.random nucleation and growth, but is related to the local synthesis conditions. Inspired by these f.ndings, dif.erent synthesis environments （N2, air, and 02） have been employed in order to tailor the length distribution. In addition to the rod length, the photoluminescence properties of.CdS nanorods can also be manipulated. Increasing the oxygen partial pressure signif.cantly changed the growth behavior of.CdS nanorods by improving the anisotropic growth.

关键词： Nanoseparation quantum rods CdS photoluminescence controlled synthesis

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

Compost Input Ef.ect on Dryland Wheat and f.rage Yields and Soil Quality

引用

Pedosphere 2018年第3期28卷 451-462页

作者： f.ancisco J. CALDERON Merle f. VIGIL joseph BENJAMIN United States Department of.Agriculture-Agricultural Research Service (USDA-ARS) Central Great Plains Research Station Akron80720 CO( USA)

Organic agricultural systems rely on organic amendments to achieve crop f.rtility requirements, and weed control must be achieved without synthetic herbicides. Our objective was to determine the crop yield and soil quality as af.ected by a transition f.om grass to dryland organic agriculture in the Central Great Plains of.North America. This study evaluated three beef.f.edlot compost(Bf.)treatments in 2010–2015 f.llowing biennial application rates: 0(control), 22.9, and 108.7 t ha^(-1) on two dryland organic cropping systems: a wheat(Triticum aestivum)-f.llow(Wf. rotation harvested f.r grain and a triticale(Triticosecale)/pea(Pisum sativum)-f.llow(T/P-f. rotation harvested f.r f.rage. The triticale + pea biomass responded positively to the 108.7-t ha^(-1) Bf. treatment,but not the 22.9-t ha^(-1) Bf. treatment. The wheat biomass was not af.ected by Bf. addition, but biomass N content *** f.edlot compost input did not increase wheat grain yields, but had a positive ef.ect on wheat grain Zn content. Soil total C and N contents increased with the rate of.108.7 t ha^(-1) Bf. af.er three applications, but not with 22.9 t ha^(-1) Bf.. Soil enzyme activities associated with N and C cycling responded positively to the 108.7-t ha^(-1) Bf. treatment. Saturated salts were high in the soil receiving 108.7 t ha^(-1) of.Bf., but did not af.ect crop yields. These results showed that Bf. was ef.ective in enhancing f.rage yields, wheat grain quality, and soil C and N, as well as specif.c microbial enzymes important f.r nutrient cycling. However, the large rates of.Bf. necessary to elicit these positive responses did not increase grain yields, and resulted in an excessive buildup of.soil P.

关键词： organic agriculture soil C soil enzyme activity soil N pea triticale

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

Phenolic constituents and anticancer properties of.Morus alba(white mulberry) leaves

引用

Journal of.Integrative Medicine 2020年第3期18卷 189-195页

作者： Eric Wei chiang Chan Siu Kuin Wong joseph Tangah Tomomi Inoue Hung Tuck Chan f.culty of.Applied Sciences UCSI University56000 CherasKuala LumpurMalaysia School of.f.undation Studies Xiamen University Malaysia43900 SepangSelangorMalaysia f.rest Research Centre Sabah Forestry Department90009 SandakanSabahMalaysia Centre f.r Environmental Biology and Ecosystem Studies National Institute for Environmental Studies(NIES)OnogawaTsukuba 305-0053Japan Secretariat of.International Society f.r Mangrove Ecosystems(ISME) Faculty of AgricultureUniversity of the RyukyusOkinawa 903-0129Japan

f.avonoids are by f.r the most dominant class of.phenolic compounds isolated f.om Morus alba leaves(MAL). Other classes of.compounds are benzof.rans, phenolic acids, alkaloids, coumarins, chalcones and stilbenes. Major f.avonoids are kuwanons, moracinf.avans, moragrols and morkotins. Other major compounds include moracins(benzof.rans), caf.eoylquinic acids(phenolic acids) and morachalcones(chalcones). Research on the anticancer properties of.MAL entailed in vitro and in vivo cytotoxicity of.extracts or isolated compounds. f.avonoids, benzof.rans, chalcones and alkaloids are classes of.compounds f.om MAL that have been f.und to be cytotoxic towards human cancer cell lines. f.rther studies on the phytochemistry and anticancer of.MAL are suggested. Sources of.inf.rmation were Pub Med,Pub Med Central, Science Direct, Google, Google Scholar, J-Stage, Pub Chem and China National Knowledge Inf.astructure.

关键词： f.avonoids Benzof.rans Cytotoxic Moracins Morachalcones Chalcomoracin

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

f.rmation and Microstructural Characterization of.Silicon-modif.ed Aluminide Coating on Nickel-based Superalloy IN738LC

引用

材料热处理学报 2004年第05B期25卷 657-660页

作者： f. Shahriari f. Ashraf.zadeh A. Monshi Materials engineering department Isfahan University of Technology Isfahan IranMaterials engineering department Isfahan University of Technology Isfahan IranMaterials engineering department Isfahan University of Technology Isfahan Iran

In this investigation, aluminide coatings used to protect industrial components at high temperature and corrosive environments were modif.ed with silicon addition and the microstructural f.atures and f.rmation mechanism were evaluated. The coating on the nickel-based superalloy IN738LC was carried out by a two stage process including siliconizing at f.rst and aluminizing thereaf.er. Pack cementation siliconizing perf.rmed at 950C f.r 2, 4 and 6 hours in several powder mixtures of.Si, A12O3 and NHiCl, then aluminum was dif.used into the surf.ce of.the specimens by an industrial aluminizing process. The modif.ed coatings were characterized by means of.standard metallography, scanning electron microscopy, energy dispersive spectroscopy and X-ray dif.raction methods. The results show that Si in the coatings mainly presents in the f.rm of.secondary phases including Cr3Si, Mo5Si3 and Nii6Ti6Si7, well distributed within the NiAl matrix. The advantages of.this two stage modif.ed coating is discussed.

关键词：显微结构 IN738LC 镍超级合金扩散渗碳处理生长机制

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

Closed-f.rm solutions f.r f.ee vibration of.rectangular f.M thin plates resting on elastic f.undation

引用

Acta Mechanica Sinica 2016年第6期32卷 1088-1103页

作者： T. f. Xu Y. f. Xing Institute of.Solid Mechanics Beihang UniversityBeijing 100191 China China Academy of.Launch Vehicle Technology R&D Center Beijing 100076 China

This article presents closed-f.rm solutions f.r the f.equency analysis of.rectangular f.nctionally graded material (f.M) thin plates subjected to initially in-plane loads and with an elastic f.undation. Based on classical thin plate theory, the governing dif.erential equations are derived using Hamilton's principle. A neutral surf.ce is used to eliminate stretching-bending coupling in f.M plates on the basis of.the assumption of.constant Poisson's ratio. The resulting governing equation of.f.M thin plates has the same f.rm as homogeneous thin plates. The separation-of.variables method is adopted to obtain solutions f.r the f.ee vibration problems of.rectangular f.M thin plates with separable boundary conditions, including, f.r example, clamped plates. The obtained normal modes and f.equencies are in elegant closed f.rms, and present f.rmulations and solutions are validated by comparing present results with those in the literature and f.nite element method results obtained by the authors. A parameter study reveals the ef.ects of.the power law index n and aspect ratio a/b on f.equencies.

关键词： f.nctionally graded material f.ee vibration Rectangular plate Close f.rm solutions Neutral surf.ce

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

Phylogenetic reconstruction of.Chirita and allies (Gesneriaceae) with taxonomic treatments

引用

Journal of.Systematics and Evolution 2011年第1期49卷 50-64页

作者： James f. SMITH Department of.Biological Sciences Boise State University

Chirita D. Don, a large genus in the subf.mily Cyrtandroideae of.Gesneriaceae, has been the subject of.much debate whether it is a natural group or not. In addition, the highly heterogeneous Chirita has also been very problematic with regard to delimitation and subdivision. Here we used the nrDNA internal transcribed spacer and cpDNA trnL-f.f.r molecular phylogenetic analaysis, combined with morphological data. Our results suggest that Chirita is an artif.cial, polyphyletic genus. The most important character that def.nes Chirita, the dorso-ventrally oblique and bilamellar stigma, has evolved convergently in dif.erent clades of.diandrous Cyrtandroideae. Chirita sensu stricto only includes the species of.Chirita sect. Chirita, whereas Chirita sect. Microchirita is an independent clade located at the basal node of.the phylogenetic tree. Chirita sect. Liebigia is closely related to Didymocarpus with an entire stigma unlike other species of.Chirita. The species of.Chirita sect. Gibbosaccus, Chiritopsis, Primulina, and Wentsaiboea f.rm a monophyletic group that is sister to a strongly supported clade comprising f.ur monotypic genera Paralagarosolen, Calcareoboea, Petrocodon, and Tengia. We f.rther analyzed the morphological evolution of.Chirita and identif.ed a series of.morphological synapomorphies f.r the monophyletic groups revealed herein, and thereby provide a taxonomic treatment in this study.

关键词： Chirita D. Don morphological evolution phylogenetic reconstruction polyphyly taxonomic treatment.

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

Electro-acupuncture to prevent prolonged postoperative ileus:A randomized clinical trial

引用

World Journal of.Gastroenterology 2010年第1期16卷 104-111页

作者： M Kay Garcia joseph S chiang Bob Thornton J Lynn Palmer Jennif.r McQuade Lorenzo Cohen Department of.Anesthesiology and Pain Medicine/Integrative Medicine M.D.Anderson Cancer CenterThe University of Texas Department of.Anesthesiology and Pain Medicine M.D.Anderson Cancer CenterThe University of Texas Department of.Palliative Care and Rehabilitation Medicine M.D.Anderson Cancer CenterThe University of Texas Department of.Behavioral Science M.D.Anderson Cancer CenterThe University of Texas Department of.GI Medical Oncology M.D. Anderson Cancer CenterThe University of Texas

AIM:To examine whether acupuncture can prevent prolonged postoperative ileus(PPOI)af.er intraperitoneal surgery f.r colon cancer. METHODS:Ninety patients were recruited f.om the f.dan University Cancer Hospital,Shanghai,China. Af.er surgery,patients were randomized to receive acupuncture(once daily,starting on postoperative day 1, f.r up to six consecutive days)or usual *** was def.ned as an inability to pass f.atus or have a bowel movement by 96 h af.er *** main outcomes were time to f.rst f.atus,time to f.rst bowel movement, and *** outcomes were quality of.lif.(QOL)measures,including pain, nausea,insomnia,abdominal distension/f.llness,and sense of.well-being. RESULTS:No signif.cant dif.erences in PPOI on day 4 (P=0.71)or QOL measures were f.und between the *** were also no group dif.erences when the data were analyzed by examining those whose PPOI had resolved by day 5(P=0.69)or day 6(P= 0.88).No adverse events related to acupuncture were reported. CONCLUSION:Acupuncture did not prevent PPOI andwas not usef.l f.r treating PPOI once it had developed in this population.

关键词： Acupuncture Gastrointestinal motility Gastrointestinal disorders Gastrointestinal neoplasms

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

Nanoscale displacement of.the image of.an atomic source of.radiation

引用

Chinese Optics Letters 2009年第2期7卷 149-151页

作者： Henk f. Arnoldus Department of.Physics and Astronomy Mississippi State University

Light emitted by an atomic source of.radiation appears to travel along a straight line （ray） f.om the location of.the source to the observer in the f.r f.eld. However, when the energy f.ow pattern of.the radiation is resolved with an accuracy better than an optical wavelength, it turns out that the f.eld lines are usually curved. We consider electric dipole radiation, a prime example of.which is the radiation emitted by an atom during an electronic transition, and we show that the f.eld lines of.energy f.ow are in general curves. Near the location of.the dipole, the f.eld lines exhibit a vortex structure, and in the f.r f.eld they approach a straight line. The spatial extension of.the vortex in the optical near f.eld is of.nanoscale dimension. Due to the rotation of.the f.eld lines near the source, the asymptotic limit of.a f.eld line is not exactly in the radially outward direction and as a consequence, the image in the f.r f.eld is slightly shif.ed. This sub-wavelength displacement of.the image of.the source should be amenable to experimental observation with contemporary nanoscale-precision techniques.

关键词： Atoms Electric dipole moments f.ow patterns Nanotechnology Vortex f.ow

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

Inf.uence of.Processing Parameters on the Strength of.Air Brazed Alumina Joints Using Aluminium Interlayer

引用

Journal of.Materials Science & Technology 2011年第7期27卷 641-646页

作者： A. Ibrahim f. Hasan Department of.Metallurgical and Materials Engineering University of Engineering and TechnologyLahore Pakistan

Alumina specimens were joined together with thin aluminium interlayer at 750 and 900°C under dif.erent applied pressures and holding time in air. f.exural strength of.the joints was then measured using a standard f.ur-point bend test method. Characterization of.the interf.ce was carried out to correlate the increase in f.exural strength with the applied pressure, holding temperature and time. The study showed that the strength of.joint is af.ected by all three parameters, i.e., processing temperature, holding time as well as applied pressure.

关键词： Pressure-assisted air brazing Alumina Aluminum Brazing Joining and Ceramic

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

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：