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一种可渗透的陶瓷模具材料

工业技术与职业教育 1980年第3期 69-72页

作者： l.b.科芬周龙

本文作者发明了一种可渗透的经煅烧而成的陶瓷模具材料,可用来代替石膏和石膏水泥。它是用硅酸乙酯作为粘合剂的陶瓷聚合体,用传统的陶瓷技术成形,然后干燥和煅烧。

关键词：成形水泥石膏硫酸钙硫酸盐矿物硅灰石矽灰石链状硅酸盐矿物陶瓷模具无水硼砂模具寿命螺钉紧固件挠曲强度

Corrosion protection of AZ91D magnesium alloy by a cerium-mol.b.enum coating-The effect of citric acid as an additive

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Journal of Magnesium and Alloys 2018年第4期6卷 356-365页

作者： I.l.lehr S.b.Saidman Instituto de Ingeniería Electroquímica y Corrosión(INIEC) Departamento de Ingeniería QuímicaUniversidad Nacional del Sur(UNS)CONICETBahía BlancaArgentina

In order to improve the corrosion resistance of AZ91D magnesium alloy,a coating was formed by a potentiostatic technique from a solutions containing Ce(NO_(3))_(3),Na_(2)MoO_(4)and citric acid(H_(3)Cit).The degree of corrosion protection achieved was evaluated in simulated physiological solution by monitoring the open circuit potential,polarization techniques and electrochemical impedance spectroscopy(EIS).Surface analysis techniques(SEM,EDS,X-ray diffraction and X-ray photoelectron spectroscopy(XPS))were used for coating *** film is mainly composed by cerium and mol.b.enum oxides and magnesium oxides and *** obtained results show that the corrosion resistance of the coated electrodes has been increased *** improvement in the anticorrosive performance is in part due to the corrosion inhibition properties of H_(3)Cit.

关键词： Cerium and mol.b.enum-based coatings AZ91D alloy Citric acid Anticorrosive properties

lichen species dominance and the resulting photosynthetic behavior of Sonoran Desert soil crust types(baja California,Mexico)

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Ecological Processes 2013年第1期2卷 64-72页

作者： burkhard büdel Mercedes Vivas Otto l lange Plant Ecology and Systematics Biology DepartmentUniversity of KaiserslauternP.O.Box 3049D-67653KaiserslauternGermany Department of Plant Science Faculty of PharmacyUniversidad Complutense de Madrid Plaza Ramóny Cajal28040MadridSpain Julius-von-Sachs-Institut für biowissenschaften University of WürzburgJulius-von-Sachs-Platz 3D-97082WürzburgGermany.

Introduction:lichen dominated biological soil crusts(bSCs)occur over large areas in the Sonoran Desert of the southwestern USA and northwest *** baja California bSCs show a distinct patchiness and several types can be *** chlorolichen-and two cyanolichen-dominated bSCs were *** hypothesize that patchiness and the resulting domination of certain functional lichen groups will result in patchiness of photosynthetic CO_(2)-uptake related to environmental factors as ***:Four different soil crust samples were placed in cuvettes and their CO_(2) exchange was recorded in an open system with an infrared gas *** blown over the bSCs had a controlled CO_(2) content of 350 *** cuvettes were operated in *** CO2 exchange was continually recorded throughout the ***:besides the dominating chlorolichens Psora decipiens and Placidium squamulosum and the cyanolichens Peltula patellata and ***,several other lichen species and 12 cyanobacterial species were found in the biological soil crusts *** chlorolichen bSCs already gained positive net photosynthesis with high air humidity alone,while the cyanolichen types did not,but showed smaller CO_(2)-uptake depression after water *** specific net photosynthesis responses to mode of hydration and to crust water content seem to correlate with precipitation characteristics of their ***:Species specific photosynthetic performance related to activation of respiration and net photosynthesis as well as to crust water content help to explain niche occupation and species composition of *** functional types have to be considered when they have a patchy distribution.

关键词： biological soil crust lichens Cyanobacteria Photosy

GAbA UPTAKE bY GAT1 MODUlATES lONG-TERM OPTICAl CHANGES FOllOWING ElECTRICAl STIMUlATION OF THE PITUITARY GlAND NEUROINTERMEDIATE l.b.

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Journal of Innovative Optical Health Sciences 2013年第3期6卷 46-57页

作者： P.KOSTERIN A.l.ObAID b.M.SAl.b.RG Department of Neuroscience Perelman School of Medicine University of Pennsylvania Philadelphia PA 19104 Department of Physiology Perelman School of Medicine University of Pennsylvania Philadelphia PA 19104

Intrinsic optical changes that follow infundibular stalk stimulation of the neurointermediate l.b. of the mouse pituitary gland exhibit three different phases that reflect three distinct physiological *** first(E-wave)is the rapid light-scattering increase that is associated with a nerve terminal volume increase(mechanical spike),and that accompanies excitation of the neurohy-pophysial terminals by the invading action potential;the second(S-wave)is the slower light-scattering decrease that is tightly corelated with the secretion of the peptide hormones oxytocin and arginine vasopressin,and the third is the long duration response(R-wave)that reflects cell volume changes in the pars *** have studied the E-wave and the S-wave in earlier *** R-wave,considered here,is sensitive to chloride replacement as wel as to blockade of chloride *** blocking GAbAA reeptors(which are ligand gated chloride channels)with pharrmacological agents,and by applying GAbA directly into the bathing solution,or evoking its release from GAbAergic inputs,we have demonstrated that this long-duration optical response is sensitive to chloride movements and reflects GAbA-induced changes in the intrinsic optical propertis of the pars *** full time course of this optical response takes mimutes and,therefore,has to embody some other process(or processes)related to the restoration of resting physiological chloride concentrations,following the opening and closing of GAbA A-reeptor *** we demonstrate that the shape of the R wave,the longlasting light-scattering signal,is indeed affected by the activity of GAT1,one of the *** GA bA transporters.

关键词： light scattering posterior pituitary pars nervosa neurohypophysis volume changes pars intermedic GAbAA receptors

Degradation patterns of silicone-based dielectric elastomers in electrical fields

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International Journal of Smart and Nano Materials 2018年第4期9卷 217-232,I0001页

作者： liyun Yu Frederikke b.Madsen Anne l.Skov Danish Polymer Centre Department of Chemical and Biochemical EngineeringTechnical University of DenmarkKgs.LyngbyDenmark

Silicone elastomers have been heavily investigated as candidates for the flexible insulator material in dielectric elastomer transducers and are as such almost ideal candidates because of their inherent softness and ***,silicone elastomers suffer from low dielectric *** shortcoming has been attempted optimized through different approaches during recent *** optimization with the sole purpose of increasing the dielectric permittivity may lead to the introduction of problematic phenomena such as premature electrical.b.eakdown due to high leakage currents of the thin elastomer *** this work,electrical.b.eakdown phenomena of various types of permittivity-enhanced silicone elastomers are *** showed that different types of polymer backbone chemistries lead to differences in electrical.b.eakdown patterns,which were revealed through SEM *** may pave the way towards a better understanding of electrical.b.eakdown mechanisms of dielectric elastomers and potentially lead to materials with increased electrical.b.eakdown strengths.

关键词： Silicone elastomers dielectric electrical.b.eakdown voltage stabilization characterization

Existence of Nondecreasing and Continuous Solutions of an Integral Equation with linear Modification of the Argument

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Acta Mathematica Sinica,English Series 2007年第9期23卷 1719-1728页

作者： J.CAbAllERO b.lóPEZ K.SADARANGANI Departamento de Matemáticas Universidad de Las Palmas de Gran CanariaCampus de Tafira Baja35017 Las Palmas de Gran CanariaSpain

We use a technique associated with measures of noncompactness to prove the existence of nondecreasing solutions to an integral equation with linear modification of the argument in the space C[0, 1]. In the last thirty years there has been a great deal of work in the field of differential equations with a modified argument. A special class is represented by the differential equation with affine modification of the argument which can be delay differential equations or differential equations with linear modifications of the argument. In this case we study the following integral equation x（t） = a（t）＋（Tx）（t） ∫0^σ（t） u（t, s, x（s）, x（λs））ds 0 〈 λ 〈 1 which can be considered in connection with the following Cauchy problem x＇（t） = u（t, s, x（t）, x（λt））, t ∈ [0, 1], 0 〈 λ 〈 1 x（0） = u0.

关键词： measure of noncompactness fixed point theorem nondecreasing solutions

Achieving large-area bulk Ultrafine Grained Cu via Submerged Multiple-pass Friction Stir Processing

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Journal of Materials Science & Technology 2013年第12期29卷 1111-1115页

作者： P. Xue b.l. Xiao Z.Y. Ma Shenyang National l.b.ratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China

large-area bulk ultrafine grained （UFG） pure Cu was successfully prepared by multiple-pass overlapping friction stir processing （FSP） under additional rapid cooling. Overlapping FSP did not exert a significant effect on the microstructure and mechanical properties of the FSP UFG Cu. Similar average grain size was achieved in the transitional zone （TZ） of the multiple-pass FSP sample compared to that in the nugget zone of the single-pass FSP sample, and the TZ exhibited a strong {111}（112） type A fiber shear texture, Very weak softening occurred in the TZ of the multiple-pass FSP UFG Cu, resulting in a relatively uniform hardness distribution throughout the whole processed zone. A high yield strength of - 310 MPa and a uniform elongation of - 13% were achieved in the bulk FSP UFG Cu. This study provides an effective strategy to prepare large-area bulk IUFG materials.

关键词： Friction stir processing Multiple-pass Ultrafine grains Microstructure Mechanical properties

COMPARISON ON REFINEMENT OF IRON POWDER bY bAll MIllING ASSISTED bY DIFFERENT EXTERNAl FIElDS

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Acta Metallurgica Sinica(English letters) 2006年第6期19卷 411-417页

作者： l.Y.Dai b.Cao M.Zhu School of Mechanical Engineering South China University of TechnologyGuangzhou 510640China Marine Engineering Institute Jimei UniversityXiamen 361021China

The cryogenic milling and milling in conjunction with dielectric barrier discharge plasma (DbDP) have been separately set up. The combined effect of low temperature and plasma on ball milling has been investigated by examining the refinement of particle size and grain size of iron powder using scanning electron microscopy, X-ray diffraction, and small angle X-ray scattering. It was found that the mean size of iron particles could reach 104nm only after 10 hours of ball milling in conjunction with DbDP, whereas a minimum average grain size of 8.4nm was obtained by cryomilling at -20℃; however, it is difficult to refine the particle size and grain size under the same milling condition in the absence of DbDP and cryogenic temperature.

关键词： ball milling cryomilling dielectric barrier discharge (DbD) nanoparticle

Disagreement between symptom-reflux association analysis parameters in pediatric gastroesophageal reflux disease investigation

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World Journal of Gastroenterology 2010年第19期16卷 2401-2406页

作者： Samuel C lüthold Mascha K Rochat Peter bhler Division of Gastroenterology Departement of Pediatrics Hospital of Fribourg CH-1708 Fribourg Switzerland Asthma and Allergy Research Group University of Munich Lindwurmstrasse 4 D 80337 Munich Germany

AIM: To assess the agreement within 3 commonly used symptom-reflux association analysis (SAA) parameters investigating gastroesophageal reflux disease (GERD) in infants. METHODS: Twenty three infants with suspected GERD were included in this study. Symptom index (SI), Symptom sensitivity index (SSI) and symptom association probability (SAP) related to cough and irritability were calculated after 24 h combined pH/multiple intraluminal impedance (MII) monitoring. Through defined cutoff values, SI, SSI and SAP values are differentiated in normal and abnormal, whereas abnormal values point towards gastroesophageal reflux (GER) as the origin of symptoms. We analyzed the correlation and the concordance of the diagnostic classification of these 3 SAA ***: Evaluating the GER-irritability association, SI, SSI and SAP showed non-identical classification of normal and abnormal cases in 39.2% of the infants. When irritability was taken as a symptom, there was only a poor inter-parameter association between SI and SSI, and between SI and SAP (Kendall’s tau b = 0.37, P ll’s tau b = 0.36, P ly). Evaluating the GER-cough association, SI, SSI and SAP showed non-identical classification of normal and abnormal cases in 52.2% of the patients. When cough was taken as a symptom, only SI and SSI showed a poor inter-parameter association (Kendall’s tau b = 0.33, P lUSION: In infants investigated for suspected GERD with pH/MII-monitoring, SI, SSI and SAP showed a poor inter-parameter association and important dis-agreements in diagnostic classification. These limitations must be taken into consideration when interpreting the results of SAA in infants.

关键词： Gastroesophageal reflux disease Infant Symptom-reflux association analysis Intraluminal impedance monitoring pH