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Surface engineering with ionic polymers on membranes for boron removal

第十三届国际复合材料会议

作者： j.S.Earl j.m.dulieu-bar.o. R.A.Shenoi School of Engineering Sciences University of Southampton Highfield Southampton SO 17 1BJ School of Engineering Sciences University of Southampton Highfield Southampton SO 17 1BJ School of Engineering Sciences University of Southampton Highfield Southampton SO 17 1BJ

＜正＞The aim of this paper is to use the thermoelastic stress analysis （TSA） technique to determine the load transfer mechanisms in sandwich construction tee joints, which have been environmentally aged, and to assess how their performance has changed with respect to the unaged case. An extensive literature review has shown that although a wealth of information exists on the long-term performance of FRP materials exposed to hygrothermal environments, the behaviour of aged composite sandwich structures has not been addressed. The purpose of this work is to begin to fill this void.

关键词： TSA deltatherm sandwich structures hygrothermal exposure ageing

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 61-69页

作者： Xiting Zhang Chenyi Fang j Paul Chen Sui Zhang Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117576Singapore Department of Civil and Environmental Engineering National University of SingaporeSingapore 119260Singapore College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Removal of boric acid from seawater and wastewater using reverse osmosis membrane technologies is imperative and yet remains inadequately addressed by current commercial *** research efforts performed post-modification of reverse osmosis membranes to enhance boron rejection,which is usually accompanied by substantial sacrifice in water *** study delves into the surface engineering of low-pressure reverse osmosis membranes,aiming to elevate boron removal efficiency while maintaining optimal salt rejection and water *** were modified by the self-polymerization and co-deposition of dopamine and polystyrene sulfonate at varying ratios and *** surfaces became smoother and more hydrophilic after *** optimum membrane exhibited a water permeability of 9.2±0.1 L·m^(-2)·h^(-1)·bar^(-1),NaCl rejection of 95.8%±0.3%,and boron rejection of 49.7%±0.1% and 99.6%±0.3% at neutral and alkaline pH,*** water permeability is reduced by less than 15%,while the boron rejection is 3.7 times higher compared to the blank *** research provides a promising avenue for enhancing boron removal in reverse osmosis membranes and addressing water quality concerns in the desalination process.

关键词： membrane low-pressure reverse osmosis boron surface engineering

Using Thermoelastic Stress Analysis to Detect Damaged and Hot Spot Areas in Structural Components

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journal of mechanics Engineering and Automation 2015年第11期5卷 623-634页

作者： Freire j. L. F. Waugh, R. C. Fruehmann, R. dulieu-bar.o., j. m. mechanical Engineering Department Pontifical Catholic University of Rio de Janeiro PUC-Rio Rio de Janeiro 22453-900 Brazil Faculty of Engineering and Environment University of Southampton Southampton SO17 1BJ UK

This paper discusses the suitability of using TSA （thermoelastic stress analysis） as an advanced tool to detect damaged areas and highly stressed （hot spot） areas in structural components. Such components can be, for example, parts of large structural panels built of welded metallic or composite materials. Besides detecting hot spot areas, it is expected that stresses in these areas can be suitably quantified and processed in order to predict crack initiation and propagation due to in-service loads. The paper starts with references to selected review and application articles on the subject. Two simple laboratory experiments are presented which illustrate the quality of the results that can be achieved using TSA. In the first experiment, a stainless steel T-joint designed to model a welded structural component is analysed. The T-joint had a machine-notched crack-like flaw close to the component＇s weld toe. The qualitative and quantitative experimental results determined along four specified areas of the T-joint model showed that TSA can indeed be used as a tool to detect loaded cracks and hot spots in large metallic structures, and that stresses can be accurately evaluated. In the second experiment, a prismatic bar made of CFRE （carbon fibre-reinforced-epoxy） was tested to locate three subsurface areas of damage introduced beforehand into the component. Two of these inside damaged areas were detected to be 3.1 mm and 7.1 mm from the observed surface. The positive results achieved with the two lab experiments, along with a review of the selected research publications, indicate that TSA application can be extended to the real-world field of structural components. Topics to be addressed in this research field should have to do with components that work under random or quasi-cyclic service loading, problems where adiabatic conditions do not prevail, and reduction of the cost of infra-red cameras.

关键词： TSA stress distribution NDT stress distribution stress concentration crack T-joint infra-red.

为保护育种者的权利而使用合成的DNA探针——关于在DNA上添加一个α-数字密码的建议

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生物技术通报 1987年第6期 1-3页

作者： j.S.Beckmann m.bar-joseph 赵明

品种保护对于育种者,和专利对于发明者一样,有着重要意义。可是,尽管这个问题很重要,如何保护品种却总是缺乏应有的分辨能力。重组DNA技术使人们能通过将标记分辨物或“签名”(标记)插入新品种的基因组中而获得提高分辨力所必需的能力... 详细信息

品种保护对于育种者,和专利对于发明者一样,有着重要意义。可是,尽管这个问题很重要,如何保护品种却总是缺乏应有的分辨能力。重组DNA技术使人们能通过将标记分辨物或“签名”(标记)插入新品种的基因组中而获得提高分辨力所必需的能力。这些标记使人们能用简易的鉴定法明白无误地辨认已登记的品种。作者将在本文中讨论这些标记的结构,并提出一种能将种种短语或名称翻译为DNA序列中的特殊密码。

关键词：育种者密码 DNA

Hydrogen absorption properties of amorphous(Ni0.6Nb0.4-yTay)100-xZrx membranes

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Progress in Natural Science:materials International 2017年第1期27卷 126-131页

作者： o.Palumbo F.Trequattrini N.Pal m.Hulyalkar S.Sarker D.Chandra T.Flanagan m.Dolan A.Paolone CNR-ISC U.O.S. La Sapienza Department of Physics Sapienza University of Rome Department of Chemical and materials Engineering University of Nevada Department of Chemistry University of Vermont CSIRo QCAT Energy 1 Technology CourtPullenvale

Ni based amorphous materials have great potential as hydrogen purification membranes. In the present work the melt spun(Ni0.6Nb0.4-yTay)100-xZrxwith y=0, 0.1 and x=20, 30 was studied. The result of X-ray diffraction spectra of the ribbons showed an amorphous nature of the alloys. Heating these ribbons below T ogen atmosphere（1-10 bar）, the amorphous structure was retained. The crystallization process was characterized by differential thermal analysis and the activation energy of such process was obtained. The hydrogen absorption properties of the samples in their amorphous state were studied by the volumetric method,and the results showed that the addition of Ta did not significantly influence the absorption properties, a clear change of the hydrogen solubility was observed with the variation of the Zr content. The values of the hydrogenation enthalpy changed from37 k j/mol for x=30 to9k j/mol for x=20. The analysis of the volumetric data provides the indications about the hydrogen occupation sites during hydrogenation, suggesting that at the beginning of the absorption process the deepest energy levels are occupied, while only shallower energy levels are available at higher hydrogen content, with the available interstitial sites forming a continuum of energy levels.

关键词： Amorphous Ni based alloy ribbons High temperature X-ray diffraction DTA Activation energy Crystallization temperature Hydrogen solubility

Closed-Form Solutions of Stress Intensity Factors for Semi-elliptical Surface Cracks in a Cylindrical bar Under Pure Tension

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Acta mechanica Solida Sinica 2022年第2期35卷 344-356页

作者： m.K.Ramezani S.Ramesh j.Purbolaksono R.Das Centre of Advanced manufacturing and materials Processing Department of Mechanical EngineeringFaculty of EngineeringUniversity of MalayaKuala Lumpur 50603Malaysia Department of mechanical Engineering University of PertaminaJakarta 12220Indonesia Sir Lawrence Wackett Aerospace Research Centre School of EngineeringRMIT UniversityMelbourneVI 3000Australia

In this work,the stress intensity factors(SIFs)for a wide range of semi-elliptical surface cracks with different inclination angles in a cylindrical bar subjected to pure tension were investigated *** main parameters considered to evaluate the SIFs were the crack size ratio(a/d),the crack aspect ratio(a/c),and the crack inclination angle(0).The dual-boundary element met hod implemented in software BEASY was used to compute the SIF values for *** her more,the general closed-form solutions were proposed to evaluate the corresponding SIFs for mode I,mode II and mode III types of fracture through curve fitting *** solutions can provide accurate and reliable values of stress intensity factors for a crack on a cylindrical bar under pure tension in a rapid way compared to those obtained using computational *** addition,these results can be used as inputs for failure studies and life evaluations of cracked cylinder under working conditions.

关键词： Stress intensity factor Surface crack Solid cylinder Closed-form solution Dual-boundary element method

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注入种子激光的频移反馈激光器

长春光学精密机械学院学报 1996年第1期19卷 41-43页

作者：梁桂云 m.W.philips j.R.m.bar 长春光机学院基础科学部英国南安谱顿大学光电子研究中心

在频移反馈Ｎｄ∶ＹＬＦ激光器中，注入单频种子激光，可以获得频率梳。实验表明，产生分立频谱所要求的最小种子功率随泵浦功率增加而增加。当频移反馈激光器的频率向高频移动时。

关键词：注入种子激光频移反馈激光

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An underlying geometrical manifold for Hamiltonian mechanics

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Frontiers of physics 2017年第1期12卷 123-131页

作者： L. P. Horwitz A. Yahalom j. Levitan m. Lewkowicz School of Physics Tel Aviv University Ramat Aviv 69978 Israel Department of Physics Bar llan University Ramat Gan 52900 Israel Department of Physics Ariel University Ariel 40700 Israel Department of Electrical and Electronic Engineering Ariel University Ariel 40700 Israel

We show that there exists an underlying manifold with a conformal metric and compatible connection form, and a metric type Hamiltonian （which we call the geometrical picture）, that can be put into correspondence with the usual Hamilton-Lagrange mechanics. The requirement of dynamical equiva- lence of the two types of Hamiltonians, that the momenta generated by the two pictures be equal for all times, is sufficient to determine an expansion of the conformal factor, defined on the geometrical coordinate representation, in its domain of analyticity with coefficients to all orders determined by functions of the potential of the Hamiltonian-Lagrange picture, defined on the Hamilton-Lagrange coordinate representation, and its derivatives. Conversely, if the conformal function is known, the potential of a Hamilton-Lagrange picture can be determined in a similar way. We show that arbi- trary local variations of the orbits in the Hamilton-Lagrange picture can be generated by variations along geodesics in the geometrical picture and establish a correspondence which provides a basis for understanding how the instability in the geometrical picture is manifested in the instability of the the original Hamiltonian motion.

关键词： geometrical Hamiltonian stability analysis coordinate mapping Riemann-Euclidean Hamiltonian equivalence

Alicyclobacillus sp. strain CC2, a thermo-acidophilic bacterium isolated from Deception Island(Antarctica) containing a thermostable superoxide dismutase enzyme

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Advances in Polar Science 2014年第2期25卷 92-96页

作者： Daniela N. Correa-Llantén maximiliano j. Amenábar Patricio A. mu?oz maría T. monsalves miguel E. Castro jenny m. Blamey Fundación Científicay Cultural Biociencia José Domingo Ca?as 2280 Santiago 8340457 Chile

A gram-positive, rod-shaped, aerobic, thermo-acidophilic bacterium CC2 （optimal temperature 55℃ and pH 4.0）, belonging to the genus Alicyclobacillus was isolated from geothermal soil collected from ＂Cerro Caliente＂, Deception Island, Antarctica. owing to the harsh environmental conditions found in this territory, microorganisms are exposed to conditions that trigger the generation of reactive oxygen species （RoS）. They must have an effective antioxidant defense system to deal with this oxidative stress. We focused on one of the most important enzymes： superoxide dismutase, which was partially purified and characterized. This study presents the first report of a thermo-acidophilic bacterium isolated from Deception lsland with a thermostable superoxide dismutase （SoD）.

关键词： Antarctica thermo-acidophile SoD geothermal Deception Island

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