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journal of materials Science & Technology 2016年第6期32卷 573-582页

作者： m.Hassan Ahmed S.Afify j.m.Tulliani Department of Applied Science and Technology Politecnico di Torino

This work investigated the sensitivity toward humidity, NO2 and H2 of ZnO modified sepiolite （Si12mg8O30（OH）4.（H2O）4.8H2O）. To this aim, sepiolite powder was first modified by leaching magnesium ions in HCI then by precipitating nano-sized Zn-based compounds under basic conditions. A subse- quent thermal treatment at 550 ℃ for 1 h was performed. The powders were characterized by X-ray diffraction （XRD）, specific surface area measurements, thermogravimetric and differential thermal anal- ysis and field emission scanning electron microscopy, as well as high resolution transmission electron microscopy. The XRD patterns showed that all leached heat treated samples were made of anhydrous sepiolite and of ZnO. Sensors were then obtained by screen printing these materials onto commercial alumina substrates with Pt electrodes. All the investigated compositions were capable of detecting NO2 down to ppm level and 20 ppm H2, at an optimal working temperature of 300°C. These detection limits are in line with the current best results reported in literature.

关键词： Clay minerals Gas sensor Sensitivity Hydrogen sensor Nitrogen Oxide

Strong emissions of blue-yellow-red regions of La and Ti modified KNaNbO_(3) ferroelectric ceramics

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journal of Advanced Ceramics 2015年第3期4卷 183-189页

作者： m.D.DURRUTHY-RODRIGUEZ m.HERNANDEZ-GARCIA j.PORTELLES j.FUENTES m.A.HERNANDEZ-LANDAVERDE m.RAmIREZ CARDONA j.m.YANEZ-LImON Departamento de Fisica Aplicada Instituto de CiberneticaMatematica y FisicaCITMA15#551VedadoLa HabanaCP 10400Cuba Facultad de Fisica Universidad de La HabanaSan Lazaro y LVedadoLa HabanaCP 10400Cuba CINVESTAV-Unidad Queretaro IPNLibramiento Norponiente 2000Fracc.Real de JuriquillaCP 76230QueretaroMexico Centro de Investigaciones en Ciencias de la Tierra y materiales Universidad Autonoma del Estado de HidalgoMexico

In this work,the results of the study on the optical properties of the perovskite structure ABO3 with La^(3+) substitution for ions K^(+) and Na^(+) in the A site and Ti^(4+) substitution for ion Nb^(5+) in the B site are *** ceramics were sintered at 1100℃ and 1190℃ and formed at 10 mPa and 80 *** ceramics were obtained with 94% of the theoretical *** piezoresponse force microscopy(PFm)showed needle-shaped grains with a size of 30 nm for the samples formed at 10 mPa at both sintering ***,the high temperature and high pressure used in formation reduced the energy of the band gap(Eg)from 3.36 to 3.09 *** emissions to 2.19,1.86,2.5,and 2.31 eV were obtained by exciting the samples at 325,373,457,and 500 nm,respectively;these emissions corresponded to blue-yellow-red regions of the visible spectrum.

关键词： emission spectra condense matter ferroelectric materials band structure X-ray diffraction(XRD)

Assessment of mercury(II) bioavailability using a bioluminescent bacterial biosensor: Practical and theoretical challenges

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journal of Environmental Sciences 2010年第8期22卷 1137-1143页

作者： Paulo R G Barrocas William m Landing Robert j m Hudson Department of Sanitation and Environmental Health National School of Public Health Oswaldo Cruz Foundation Department of Oceanography Florida State University. Tallahassee Department of Natural Resources and Environmental Sciences University of Illinois

Critical methodological challenges in the microbial biosensor approach to assessing Hg（II） bioavailability were evaluated from the perspective of analytical chemists. The main challenge stems from the fact that the chemical speciation of Hg（II） in natural waters exerts a major control on its bioavailability, yet its natural complexation equilibria are extensively altered during conventional bioassays. New data, obtained using a bioluminescent Hg（II）-biosensor, that illustrate these challenges are presented and potential solutions proposed.

关键词： mercury bioavailability biosensor chemical speciation bioluminescent

Asymptotic dynamics of the alternate degrees of freedom for a two-mode system:An analytically solvable model

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Chinese Physics B 2013年第2期22卷 71-75页

作者： m.Arsenijevi j.jekni-Dugi m.Dugi Department of Physics Faculty of ScienceKragujevacSerbia Department of Physics Faculty of Science and MathematicsNiSerbia

The composite systems can be non-uniquely decomposed into parts（subsystems）.Not all decompositions（structures） of a composite system are equally physically *** this paper we answer on theoretical ground why it may be *** consider a pair of mutually un-coupled modes in the phase space representation that are subjected to the independent quantum amplitude damping *** investigating asymptotic dynamics of the degrees of freedom,we find that the environment is responsible for the structures *** one structure is distinguished by both locality of the environmental influence on its subsystems and a classical-like description.

关键词： amplitude dissipative channel two-mode state Kraus representation alternate degrees of freedom

State of the Art on micromilling of materials,a Review

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journal of materials Science & Technology 2012年第8期28卷 673-685页

作者： m.A.Cmara j.C. Campos Rubio A.m. Abro j.P. Davim Department of mechanical Engineering Universidade Federal de Minas GeraisAv.Ant onio Carlos6627-Pampulha Belo Horizonte MGCEP:31.270-901Brazil Department of mechanical Engineering University of AveiroCampus Universitrio de Santiago3810-193AveiroPortugal

The trend towards miniaturization has increased dramatically over the last decade, especially within the fields concerned with bioengineering, microelectronics, and aerospace. micromillin8 is among the principal manu- facturing processes which have allowed the development of components possessing micrometric dimensions, being used to the manufacture of both forming tools and the final product. The aim of this work is to present the principal aspects related to this technology, with emphasis on the work material requirements, tool ma- terials and geometry, cutting forces and temperature, quality of the finished product, process modelling and monitoring and machine tool requirements. It can be noticed that size effect possesses a relevant role with regard to the selection of both work material （grain size） and tooling （edge radius）. Low forces and temper- ature are recorded during micromillin8, however, the specific cutting force may reach high values because of the ploughing effect observed as the uncut chip thickness is reduced. Finally, burr formation is the principal concern with regard to the quality of the finished part.

关键词： micro-milling micromachining Size effect miniaturization

DISSOLUTION KINETICS OF PHOSPHATE ORE IN ACIDIC SOLUTIONS

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Chinese journal of Chemical Engineering 1994年第2期2卷 13-22页

作者：马三剑 E.T.m.j.martynowicz G.j.Witkamp G.m.vanRosmalen Faculty of Chemical Technology and material Science Delft University of TechnologyLeeghwaterstraat 442628RZ DelftThe Netherlands

The dissolution kinetics of Florida and jordan phosphate ore was studied in diluted nitric acid (0.2, 0.5, 1.0 mol ·L-1), and in phosphoric acid (55 wt% H3PO4) aqueous solutions. It was found that the hydrogen ions concentration is a controlling factor, but the calcium ions concentration can not affect the dissolution rate in the range of 0.0 and 2.0 wt% Ca2+. The effects of temperature, stirring intensity and the size of ore particles were also investigated. The transfer of hydrogen ion depends on the diffusion, while the calcium ions transfer is assumed to be depended on mechanically stripping. The shrinking core model with hydrogen ions diffusion control match the experimental results.

关键词： dissolution kinetics phosphate ore diffusion mechanically stripping hydrogen calcium ions concentration shrinking core model

Consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTECH 2024年第2期5卷 239-246页

作者： j.m.Lukasiewicz C.C.m.van de Wiel L.A.P.Lotz m.j.m.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically modified Organisms Directive(2001/18/EC)in the European *** the proposal of the European Commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques Consumer transparency Plant products

Nonlinear elastic constitutive relations of residually stressed composites with stiff curved fibres

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Applied mathematics and mechanics(English Edition) 2022年第10期43卷 1515-1530页

作者： m.H.B.m.Shariff j.merodio R.Bustamante Department of mathematics Khalifa University of Science and TechnologyAbu Dhabi127788United Arab Emirates Departamento de matemática Aplicada a las TIC ETS de Ingeniería de Sistemas InformaticosUniversidad Politecnica de MadridMadrid28031Spain Departamento de Ingeniería mecánica Universidad de ChileBeauchef 851Santiago CentroSantiago8370448Chile

mechanical models of residually stressed fibre-reinforced solids,which do not resist bending,have been developed in the ***,in some residually stressed fibre-reinforced elastic solids,resistance to fibre bending is significant,and the mechanical behavior of such solids should be ***,in this paper,we model the mechanical aspect of residually stressed elastic solids with bending stiffness due to fibre curvature,which up to the authors’knowledge has not been mechanically modeled in the *** proposed constitutive equation involves a nonsymmetric stress and a couple-stress *** invariants are used in the constitutive equation,where each spectral invariant has an intelligible physical meaning,and hence they are useful in experiment and analysis.A prototype strain energy function is ***,we use this prototype to give results for some cylindrical boundary value problems.

关键词： fibre-reinforced solid residual stress bending stiffness spectral invariant second gradient finite elasticity

Cognitive changes associated with ADT： a review of the literature

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Asian journal of Andrology 2012年第2期14卷 232-238页

作者： Rhoda j jamadar mary j Winters Pauline m maki Center for Cognitive medicine Department of Psychiatry university of Illinois at Chicago Chicago IL 60612 USA Department of Psychology University of Illinois at Chicago Chicago IL 60612 USA

The use of androgen deprivation therapy （ADT） has increased since the early 1990s after early detection efforts and greater use of the prostate-specific antigen （PSA） test. Although ADT is associated with favorable clinical outcomes, ADT has been associated with an increased risk for cardiovascular disease, increased serum cholesterol, triglycerides, insulin resistance, body mass index and fat body mass. Here we review findings from 11 clinical studies examining the effects of ADT on cognition as measured by standardized tests in cognitive domains such as verbal and spatial memory. most of these studies have important limitations, including small sample sizes, suboptimal control groups and baseline group differences in confounding factors. Despite these limitations, the best designed studies, those comparing patients on ADT to healthy controls, generally suggest that spatial memory might be especially sensitive to the effects of ADT. Critically, to date there is only one study involving random assignment of ADT versus close clinical observation. That study revealed a decrease in verbal memory with ADT, but was limited in sample size and did not include a measure of spatial memory. A recent observational study revealed no substantial evidence of cognitive impairment with ADT, even in the domain of verbal memory. Like the randomizedstudy, however, this large observational study lacked a measure of spatial memory. Overall, the studies with the best controls suggest a potential negative impact of ADT on spatial memory, and perhaps verbal memory, and a need for continued investigation of the impact of ADT on cognition, particularly in these two cognitive domains.

关键词： androgen deprivation therapy cognition prostate cancer

An Awareness-Adoption matrix for Strategic Decision making in Agricultural Development Projects: A Case Study in Yunnan Province, China

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journal of Integrative Agriculture 2009年第9期8卷 1112-1119页

作者： m Subedi T j Hocking m A Fullen A R mcCrea E milne D j mitchell School of Applied Sciences The University of Wolverhampton Wolverhampton WV1 1LY UK Department of Geography University of Leicester Leicester LE1 7RH UK

Significant achievements have been made in generating sustainable agricultural technologies in developing countries. Usually, these new technologies have been more effective in increasing production and productivity than existing technologies. However, many new technologies considered ‘effective’ have not been successful in alleviating the associated sustainability problems, due to poor adoption by targeted users. Success of any novel technical intervention should be judged on the basis of how widespread adoption is in the target area by targeted users. In this context, a case study identified the factors affecting farmers’ adoption of improved technologies extended by an agricultural development project in a rural Village in Yunnan Province, China. Initial adoption/adaptation of project technologies was influenced by farmers’ awareness of the technology. Farmers were more aware of polythene mulch, contour cultivation, intercropping and tree planting technologies than others. This led to a comparatively high initial uptake of polythene mulch, contour cultivation, sweet chestnut, and intercropping technologies. Farmers had inadequate knowledge about some Project technologies, the adoption of which was particularly low. This reveals the need for increasing farmers’ awareness about the rationale for Project technologies to achieve greater adoption/adaptation of project technologies by farmers over wider areas. Farmers’ testing of the technology leads to better adoption/adaptation compared to mere awareness. However, considerable time and resources are required for testing/trying technologies. This justifies the usefulness of comparatively quick and less resource demanding options for awareness creation. Development of effective cropping technologies is important for sustainable agricultural development. The success of any agricultural development project, especially in terms of improving sustainability, depends on how widely those improved technologies are adopted/adap

关键词： awareness-adoption matrix sustainable agriculture China