检索结果-南通市图书馆

Chinese.j.urnal Of Geochemistry 2013年第1期32卷 19-26页

作者： Sajil Kumar P.j. Davis Delson P. Vernon j.G. james e.j. Brandenburg Technical University Cottbus-03046 Germany ITALCONSULT Riyadh-11421 Saudi Arabia Budapest University of Technology and economics (BMe) Budapest-Pf. 91 H-152 Hungary Water Institute Karunya UniversityCoimbatore-641114 India

A linear regression model in conjunction with cluster analysis was applied to the groundwater quality parameters for the Vaniyambadi industrial area, Tamil Nadu, India. These physico-chemical parameters were collected from 25 wells by intensive groundwater sampling conducted during january 2010. All the major ions, pH and electrical conductivity were analyzed. The abundances of cations were in the order of Na e of anions were in the order of Cl espectively. This was in agreement with the water types, Na-Cl and Na-Ca-HCO3, determined by the Piper plot. High concentrations of the ions Na, Cl and SO4 were recorded near the tanneries that operate within the study area. While the elevated concentrations of HCO3 and F were observed away from the tanneries. This peculiar hydrochemical behaviour suggests that the chemistry of water is predominantly influenced by tannery effluents and weathering of silicate minerals. Results of the linear regression model yielded 11 regression equations for the 5 most correlated parameters. A dendrogram from the cluster analysis showed 2 major clusters representing the influence of tanneries and geological formations in the study area, which confirmed the results of major ion chemistry.

关键词：线性回归模型地下水化学工业区印度 LRM 聚类分析物理化学参数研究区域

Thermoluminescence characterization of natural and synthetic irradiated Ce-monazites

在线全文

学校读者我要写书评

暂无评论

journal of Rare earths 2024年第4期42卷 643-650页

作者： V.Correcher C.Boronat j.Garcia-Guinea j.F.Benavente T.Rivera-Montalvo CIeMAT Av.Complutense 4028040MadridSpain MNCN-CSIC J.Gutierrez Abascal 228006MadridSpain Instituto Politécnico Nacional CICATA-IPNAv.Legaria 694Mexico City11500Mexico

The thermoluminescence(TL)emission of synthetic and natural Ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitative point of view trying to link each TL peak to a chemical-physical *** kinetic parameters that lead the luminescence processes were calculated by means of variable heating rate and computing glow curve deconvolution methods and allow identifying three groups of components at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic CePO_(4):Nd_(0.20),La_(0.25)).The main differences appreciated in these complex TL curves are mainly due to(i)the content of impurities(natural sample contains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of crystallinity of the samples which is directly related to the type of impurities(synthetic monazite relies only on Nd and La).The behavior of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity increases linearly as the dose increases without changes in the position of the maxima,denoting first-order kinetic luminescence *** peak could be mostly associated with structural defects(i.e.,phase transitions),chemical reactions(i.e.,Ce3+?Ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic defects(i.e.,Frenkel defects,ODCs or NBOHCs).

关键词： Thermoluminescence Kineticparameters Phosphate Ce-monazite Defects Rare earths

Removal of As(V)in the presence of Cr(VI)in contaminated water from the Bajio region of Mexico using ferrihydrite-functionalized graphene oxide(GOFH):A case study

在线全文

学校读者我要写书评

暂无评论

emerging Contaminants 2024年第3期10卷 134-144页

作者： D.R.joya-Cardenas j.P.Rodríguez-Caicedo M.A.Corona-Rivera N.Saldana-Robles C.e.Damian-Ascencio A.Saldana-Robles Graduate Program in Biosciences University of GuanajuatoIrapuato36500Mexico Facultad de Ingenierías y Tecnologías Instituto XeriraUniversidad de SantanderBucaramanga680003Colombia Chemical engineering Unit Academic Multidisciplinary Region Altiplano UAMRA.Autonomous University of San Luis PotosíMatehualaSan Luis Potosí78000Mexico Department of Agricultural engineering University of GuanajuatoIrapuato36500Mexico Department of Mechanical engineering University of GuanajuatoSalamanca36800Mexico Mechanical engineering Department Virginia TechBlacksburgVA24061USA

The presence of heavy metals such as arsenic(As)and chromium(Cr)can be considered one of the most toxic heavy *** study aims to develop and evaluate a graphene oxide(GO)based material functionalized with ferrihydrite for the removal of As(V)in the presence of Cr(VI).The adsorbent ferrihydrite-functionalized graphene oxide(GOFH)was characterized by SeM,FTIR,XRD,XPS,surface charge,BeT and *** adsorption capacities for As(V)and Cr(VI)were 160 and 66 mg g^(-1)respectively at pH 4 and 298 K,fitting the Langmuir *** binary systems,GOFH adsorbed As(V)with an adsorption capacity of 137 mg g^(-1)in the presence of 20 mg L^(-1)Cr(VI)at room *** analysis revealed an exothermic and spontaneous ***,GOFH effectively removed several coexisting anions from groundwater,including SO_(4)^(2-),CO_(3)^(2-)and Cl^(-).This work evidences the potential of GOFH for competitive adsorption of priority pollutants from complex *** GOFH material represents a technically and economically viable technology for application in groundwater decontamination,as it requires inexpensive precursors and ambient conditions during synthesis and operation.

关键词： Competition Ions Contamination Groundwater Adsorption capacity

Study of the Physical and Mechanical Properties of Titanium in Volume by the MeAM Method

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Modeling and Numerical Simulation of Material Science 2024年第1期14卷 58-68页

作者： Yahnn j. Mighensle Mimboui Alain S. Dzabana Honguelet Timothée Nsongo Faculty of Science and Technology Marien Ngouabi University Brazzaville Congo Research Group on Physical and Chemical Properties of Materials Brazzaville Congo Association Alpha Sciences Beta Technologies Brazzaville Congo Geological and Mining Research Centre Brazzaville Congo

In this work we present the results of our study on the physical and mechanical properties of titanium in volume. The work consisted in determining its physical and mechanical properties under different crystallographic structures (HCP, FCC, BCC and SC) using the Modified embedded Atom Method (MeAM) and the MeAM potential of titanium. We used the LAMMPS calculation code, based on classical molecular dynamics, to determine the most stable structure of titanium, which is the hexagonal compact structure (HCP) with crystal parameters a = 2.952 Å and c = 4.821 Å and a cohesion energy of -4.87 eV. This structure is seconded by the cubic centred structure (BCC) with a lattice parameter a = 3.274 Å and a cohesive energy of -4.84 eV. It was shown that titanium can crystallise into a third structure which is the face-centred cubic (FCC) structure with a lattice parameter a = 4.143 Å and a cohesive energy of -4.82 eV. The results obtained in this study were compared with the theoretical results and showed considerable agreement.

关键词： MeAM Potential LAMMPS Code Molecular Dynamics elastic Constants Modules Ovito

《耳鸣患者皮层和皮层下听觉区超高场MRI的研究》摘译

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

听力学及言语疾病杂志 2024年第4期32卷 384-385页

作者：申丽君文之(摘译) 曹永茂(审校) Berlot e Arts R Smit j 武汉大学人民医院耳鼻咽喉头颈外科武汉430060 武汉大学人民医院放射科

耳鸣研究的难点之一在于难以将耳鸣感知与其他合并症进行区分,例如听力损失和声音耐受性降低(DST)经常同时出现。在研究耳鸣动物模型时,区分起来尤其困难。对耳鸣患者研究时往往未能充分控制混杂因素。最近的研究表明,在仔细控制听力损... 详细信息

耳鸣研究的难点之一在于难以将耳鸣感知与其他合并症进行区分,例如听力损失和声音耐受性降低(DST)经常同时出现。在研究耳鸣动物模型时,区分起来尤其困难。对耳鸣患者研究时往往未能充分控制混杂因素。最近的研究表明,在仔细控制听力损失和DST后,耳鸣组和对照组之间先前存在的差异消失了。另一个难点是非侵入性测量技术的空间分辨率有限。为了检测诸如内侧膝状体(MGB)和下丘(IC)等皮层下听觉结构的频率响应特异性,需要高空间分辨率。由于这些结构仅为几立方毫米(例如内侧膝状体为4 mm×5 mm×4.5 mm),常规磁场(3T及以下)下的功能磁共振成像(fMRI)的空间分辨率为2 mm×2 mm×2 mm,无法检查这些微小结构中频率响应的特异性。7T的超高场(UHF)磁共振成像(MRI)提供的灵敏度有足够的分辨率显示微小的听觉皮层下结构的响应,便于详细描述其频率拓扑。本实验研究旨在UHF-MRI应用于耳鸣患者探索耳鸣的机制。

关键词：内侧膝状体立方毫米耳鸣患者混杂因素听力损失皮层下高空间分辨率动物模型

Themechanism of resistance to CDK4/6 inhibition and novel combination therapy with RNR inhibition for chemo-resistant bladder cancer

在线全文

学校读者我要写书评

暂无评论

Cancer Communications 2024年第6期44卷 700-704页

作者： Zhichao Tong Yubo Zhao Shiyu Bai Benedikt ebner Lou Lienhard Yuling Zhao Ziqi Wang Qi Pan Pengyu Guo Thilo Bracht Barbara Sitek jürgen e.Gschwend Wanhai Xu Roman Nawroth Department of Urology Harbin Medical University Cancer HospitalHarbinHeilongjiangP.R.China NHC and CAMS Key Laboratory of Molecular Probe and Targeted Theranostics Harbin Medical UniversityHarbinHeilongjiangP.R.China Department of Urology Klinikum rechts der IsarTechnical university of MunichMunichGermany Department of Urology The Fourth Hospital of Harbin Medical UniversityHarbinHeilongjiangP.R.China Department of Urology Ludwig-Maximilians-University of MunichMunichGermany Department of Urology Shanghai General HospitalShanghai Jiao Tong UniversityShanghaiP.R.China Medizinisches Proteom-Center Ruhr-Universität BochumBochumGermany Clinic for Anesthesiology Intensive Care and Pain TherapyUniversity Medical Center Knappschaftskrankenhaus BochumBochumGermany

Bladder cancer(BCa)is the most prevalent urological cancer worldwide[1].A significant proportion of BCa(89%)exhibits molecular alterations in the cell cycle pathway,and targeting cyclin-dependent kinases 4 and 6(CDK4/6)is deemed as a promising therapeutic strategy[2].Selective inhibitors of CDK4/6(CDK4/6is)have been approved by the US Food and Drug Administration(FDA)[3].

关键词： bladder CDK4 alterations

Statistical evaluation of 571 GaAs quantum point contact transistors showing the 0.7 anomaly in quantized conductance using cryogenic on-chip multiplexing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chip 2024年第3期3卷 21-28页

作者： Pengcheng Ma Kaveh Delfanazari Reuben K.Puddy jiahui Li Moda Cao Teng Yi jonathan P.Griffiths Harvey e.Beere David A.Ritchie Michael j.Kelly Charles G.Smith Cavendish Laboratory Department of PhysicsUniversity of CambridgeCambridge CB30HEUK james Watt School of engineering University of GlasgowGlasgow G128QQUK electrical engineering Division University of CambridgeCambridge CB30FAUK

Themass production and the practical number of cryogenic quantum devices producible in a single chip are limited to the number of electrical contact pads and wiring of the cryostat or dilution *** is,therefore,beneficial to contrast themeasurements of hundreds of devices fabricated in a single chip in one cooldown process to promote the scalability,integrability,reliability,and reproducibility of quantum devices and to save evaluation time,cost and ***,we used a cryogenic on-chip multiplexer architecture and investigated the statistics of the 0.7 anomaly observed on the first three plateaus of the quantized conductance of semiconductor quantum point contact(QPC)*** single chips contain 256 split gate field-effect QPC transistors(QFeT)each,with two 16-branch multiplexed source-drain and gate pads,allowing individual transistors to be selected,addressed and controlled through an electrostatic gate voltage process.A total of 1280 quantum transistors with nano-scale dimensions are patterned in 5 different chips of GaAs *** the measurements of 571 functioning QFeTs taken at temperatures T[1.4 K and T[40 mK,it is found that the spontaneous polarisation model and Kondo effect do not fit our ***,some of the features in our data largely agreed with van Hove model with short-range *** approach provides further insight into the quantum mechanical properties and microscopic origin of the 0.7 anomaly in QFeTs,paving the way for the development of semiconducting quantum circuits and integrated cryogenic electronics,for scalable quantum logic control,readout,synthesis,and processing applications.

关键词： Cryogenic chip Cryogenic quantum multiplexer Semi-conductor quantum integrated circuit Quantumﬁeld effect transistors Quantum point contacts Chip-scale cryogenic electronics

Quantitative Mapping of Transient Thermodynamic States in Ultrafast Laser Nanostructuring of Quartz

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Ultrafast Science 2024年第2期4卷 9-18页

作者： H.D.Nguyen A.Tsaturyan S.Sao joao R.Dwivedi A.Melkonyan C.D’Amico e.Kachan j.P.Colombier G.Kermouche R.Stoian Laboratoire Hubert Curien UMR 5516 CNRSUniversite Jean Monnet42000 Saint EtienneFrance Laboratoire George Friedel UMR 5307 CNRSEcole des Mines de Saint Etienne42000 Saint EtienneFrance

Understanding material structural reaction to light is of utmost importance to advance processing resolution in ultrafast laser volume structuring into the *** thermodynamic pathways are required to quench energy transport in the most rapid manner and to confine the process to nanometer lengths,bypassing optical *** material dynamics under confinement,with in situ access to transient local temperature and density parameters,thus becomes key in understanding the *** report in situ reconstruction of thermodynamic states over the entire matter relaxation path in bulkα-quartz irradiated by ultrafast nondiffractive laser beams using time-resolved qualitative and quantitative optical phase *** dynamics indicate rapid spatially confined crystalline-to-amorphous transition to a hot dense fused silica *** exceeds 20%and the matrix temperature rises to more than 2,000 K in the first *** structural state relaxes in hundreds of *** dispersion and time design of the optical beam to picosecond durations increases the spatial confinement and triggers an extreme nanostructuring process based on nanocavitation that occurs within the amorphizing material,where the low-viscosity phase lowers the mechanical requirements for the *** feature scales of less than a tenth of the optical wavelength are obtained in the *** allows for structural and morphological nanoscale material features under 3D confinement that can engineer optical materials.

关键词： Quartz hundreds qualitative

europium recovery process by means of polymeric nanoparticles functionalized with acrylic acid,curcumin and fumaramide

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 Rare earths 2024年第10期42卷 1950-1959页

作者： P.A.Martínez-Montoya j.M del Río A.de.j.Morales-Ramirez M.Corea escuela Superior de Ingeniería Química e Industrias extractivas ESIQIE-IPNDepartamento de Ingeniería Metalúrgica UPALM S/N Col.LindavistaGustao A.MaderoCDMXC.P.07738Mexico escuela Superior de Ingenieria Química e Industrias extractivas ESIQIE-IPNLaboratorio de Investigación en Polímeros y NanomaterialesUPALM S/N Col.LindavistaGustavoA.MaderoCDMXC.P.07738Mexico Centra de Investigación e Innovación Tecnológica CIITEC-IPNCda.de CECATIs/nSanta CatarinaAzcapotzalcoC.P.02250CDMXMexico

Polymeric nanoparticles of poly(methyl methacrylate)were obtained by emulsion polymerization techniques in a proce ss of two *** particles were functionalized with acrylic acid,curcumin,and fumaramide and three series of polymeric particles were *** incorporation of functional groups was confirmed by Fourier transform-infrared spectrosocopy(FT-IR)and ultraviolet-visible(UV-Vis)*** spherical morphology of particles with an average diameter of 100 nm was observed by scartning electron microscopy(SeM).The polymeric materials were used for recovery of[eu]from synthetic *** nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover more than 85%of[eu]at pH of *** images of SeM after extraction process show arrays between particles with larger average particle sizes to 1.5 *** addition,the particles have a good stripping capacity,exceeding 50%of it,maintaining their homogeneity in morphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second model order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of 6.

关键词： [eu]recovery Chelating effect extraction process Stripping process emulsion polymerization Rare earths

Doping effect of Poly(vinylidene fluoride) on Carbon Nanofibers Deduced by Thermoelectric Analysis of Their Melt Mixed Films

在线全文

学校读者我要写书评

暂无评论

Chinese.j.urnal of Polymer Science 2024年第11期 1802-1810页

作者： A.j.Paleo V.M.Serrato j.M.Mánuel O.Toledano e.Mu?oz M.Melle-Franco B.Krause P.P?tschke K.Lozano 2C2T-Centre for Textile Science and Technology University of Minho Campus de Azurém Florida Institute of Technology The Aerospace Corporation Department of Condensed Matter Physics and Institute of Research on electron Microscopy and Materials(IMeYMAT) Faculty of Sciences University of Cádiz CICeCO – Aveiro Institute of Materials Department of Chemistry University of Aveiro UNeD-Universidad Nacional de educación a Distancia Facultad de Física Pontificia Universidad Católica de Chile Leibniz-Institut für Polymerforschung Dresden e.V.IPF Department of Mechanical engineering University of Texas Rio Grande Valley

The effect of temperature on the electrical conductivity （σ） and Seebeck coefficient （S） of n-type vapor grown carbon nanofibers （CNFs）and poly（vinylidene fluoride）(PVDF) melt-mixed with 15 wt%of those CNFs is *** 40°C,the CNFs show stable n-type character (S=-4.8μV·K-1) with anσof ca.165 S·m-1,while the PVDF/CNF composite film shows anσof ca.9 S·m-1and near-zero S (S=-0.5μV·K-1).This experimental reduction in S is studied by the density functional tight binding （DFTB） method revealing a contact electron transfer from the CNFs to the PVDF in the ***,in the temperature range from 40°C to 100°C,theσ（T） of the CNFs and PVDF/CNF film,successfully described by the 3D variable range hopping （VRH） model,is explained as consequence of a thermally activated backscattering *** the contrary,the S（T）from 40°C to 100°C of the PVDF/CNF film,which satisfactorily matches the model proposed for some multi-walled carbon nanotube （MWCNT）doped mats;however,it does not follow the increase in S（T） found for *** these findings are presented with the aim of discerning the role of these n-type vapor grown carbon nanofibers on theσand S of their melt-mixed polymer composites.

关键词：