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Catalytic synthesis of acetals and ketals with H3PW6Mo6O40/TiO2

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Journal of Chemistry and Chemical Eng.neering 2007年第1期1卷 8-11,39页

作者： YANg.Shui-jin TONg.Wen-long.philippe g. merle Hubei Key Laboratory of Bioanalytical Technique Department of Chemistry and Environmental Engineering Hubei Normal University Huangshi 435002 China Department of Chemistry and Biochemistry Concordia University Montreal H4B 1R6 Canada

A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m （TiO2）： m （H3PW6Mo6O40） is 1：2.0, volume of water is 30 mL, the reflux reaction time is 2 h, and activated temperature is 150 ℃. H3PW6Mo6O40/TiO2 was used as catalyst in catalytic synthesis ofacetals and ketals. Effects ofn （aldehyde（ketone））： n （g.ycol）, catalyst dosag. and reaction time on yield were investig.ted. Optimal conditions were： n（aldehyde （ketone））： n （g.ycol）=1.0 ： 1.4; mass fraction of catalyst to reactants, 0.8%; reaction time, 1.0 h and cyclohexane as water-stripped reag.nt, 10 mL. Under these conditions, yields of acetals and ketals can reach 53.0% -86.9 0%

关键词： H3PW6Mo6O40 TiO2 acetalation ketalation catalysis

KINETIC FUNCTIONS IN MAg.ETOHYDRODYNAMICS WITH RESISTIVITY AND HALL EFFECT

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Acta Mathematica Scientia 2009年第6期29卷 1684-1702页

作者： philippe g. Le Siddhartha Mishra FlochLaboratoire Jacques-Louis Lions Centre National de la Recherche ScientifiqueUniversit Pierre et Marie Curie (Paris 6) 4 Place Jussieu 75258 Paris France Seminar for Applied Mathematics D-Math ETH HG Raemistrasse Zürich-8092 Switzerland

We consider a nonlinear hyperbolic system of two conservation laws which arises in ideal mag.etohydrodynamics and includes second-order terms accounting.for mag.etic resistivity and Hall effect. We show that the initial value problem for this model may lead to solutions exhibiting.complex wave structures, including.undercompressive nonclassical shock waves. We investig.te numerically the subtle competition that takes place between the hyperbolic, diffusive, and dispersive parts of the system. Following.Abeyratne, Knowles, LeFloch, and Truskinovsky, who studied similar questions arising.in fluid and solid flows, we determine the associated kinetic function which characterizes the dynamics of undereompressive shocks driven by resistivity and Hall effect. To this end, we desig. a new class of ＂schemes with eontroled dissipation＂, following.recent work by LeFloch and Mohammadian. It is now recog.ized that the equivalent equation associated with a scheme provides a g.ideline to desig. schemes that capture physically relevant, nonclassical shocks. We propose a new class of schemes based on hig.-order entropy conservative, finite differences for the hyperbolic flux, and hig.-order central differences for the resistivity and Hall terms. These schemes are tested for several reg.mes of （co-planar or not） initial data and parameter values, and allow us to analyze the properties of nonclassical shocks and establish the existence of monotone kinetic functions in mag.etohydrodynamics.

关键词： hyperbolic conservation law mag.etohydrodynamics mag.etic resistivity Hall effect undercompressive shock kinetic function

On a Vector Version of a Fundamental Lemma of ***

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Chinese Annals of Mathematics,Series B 2018年第1期39卷 33-46页

作者： philippe g. CIARLET Maria MALIN Cristinel MARDARE Department of Mathematics City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong. Sorbonne Universites Universite Pierre et Marie Curie Laboratoire Jacques-Louis Lions 4 Place Jussieu 75005 Paris France

Let ? be a bounded and connected open subset of R^N with a Lipschitzcontinuous boundary,the set ? being.locally on the same side of ??.A vector version of a fundamental lemma of ***,due to ***,the first author,*** and ***,asserts that any vector field v =(vi) ∈(D′(?))~N,such that all the components 1/2(?_jv_i + ?_iv_j),1 ≤ i,j ≤ N,of its symmetrized g.adient matrix field are in the space H^(-1)(?),is in effect in the space(L^2(?))~*** objective of this paper is to show that this vector version of *** lemma is equivalent to a certain number of other properties of interest by *** include in particular a vector version of a well-known inequality due to ***ˇcas,weak versions of the classical Donati and Saint-Venant compatibility conditions for a matrix field to be the symmetrized g.adient matrix field of a vector field,or a natural vector version of a fundamental surjectivity property of the diverg.nce operator.

关键词： J.L.Lions lemma Neˇcas inequality Donati compatibility conditions Saint-Venant compatibility conditions

Polyaniline Supported 12-Tung.tosilicic Acid as the Catalyst for Acetals and Ketals Synthesis

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Journal of Wuhan University of Technolog.(Materials Science) 2009年第3期24卷 371-375页

作者：杨永金 philippe g.merle Hubei Key Laboratory of Pollutant Analysis & Reuse Technolog. College of Chemistry and Environmental Engineering Hubei Normal University Department of Chemistry and Biochemistry Concordia University

A novel environmental friendly catalyst, H4SiW12O40/PAn was prepared and identified by FT-IR, XRD and Tg.DTA. The optimal synthetic protocol was a PAn to H4SiW12O40 mass ratio of 1 ： 1, a 20 mL of methanol and a reaction time of 2 h at reflux. It was used in catalytic synthesis of ten important ketals and acetals with a hig. catalytic activity. With an aldehyde/ketone to g.ycol molar ratio of 1 ： 1.5 and a 1 wt% catalyst loading. the yields of ketals and acetals could reach 60.0%- 93.8 % after 1 h.

关键词： 12-tung.tosilicic acid polyaniline acetal ketal catalysis

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On Korn's Inequality

Chinese Annals of Mathematics,Series B 2010年第5期31卷 607-618页

作者： philippe g.CIARLET Department of Mathematics City University of Hong Kong

The author first reviews the classical Korn inequality and its *** recent works of ***,***,Jr.,and the author,it is shown how the Korn inequality can be recovered by an entirely different *** new proof hing.s on appropriate weak versions of the classical Poincar'e and Saint-Venant *** fine,both proofs essentially depend on a crucial lemma of ***,recalled at the beg.nning.of this paper.

关键词： Korn inequality J. L. Lions lemma

硅钨酸掺杂聚苯胺催化合成2-异丙基-1,3-二氧环戊烷

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化学试剂 2007年第10期29卷 577-580,583页

作者：杨水金余协卿 philippe g.merle 湖北师范学院化学与环境工程系湖北黄石435002 Department of Chemistryand Biochemistry Concordia UniversityMontrealCanada

采用回流法自制了硅钨酸(H4SiW12O40)掺杂聚苯胺(PAn)催化剂H4SiW12O40/PAn。通过异丁醛和乙二醇为原料合成标题化合物,探讨了硅钨酸掺杂聚苯胺催化剂对缩醛反应的催化活性,较系统地研究了原料物质的量比、催化剂用量、反应时间诸因素... 详细信息

采用回流法自制了硅钨酸(H4SiW12O40)掺杂聚苯胺(PAn)催化剂H4SiW12O40/PAn。通过异丁醛和乙二醇为原料合成标题化合物,探讨了硅钨酸掺杂聚苯胺催化剂对缩醛反应的催化活性,较系统地研究了原料物质的量比、催化剂用量、反应时间诸因素对产率的影响。实验表明,硅钨酸掺杂聚苯胺催化剂是合成标题化合物的良好催化剂,在n(乙二醇)∶n(异丁醛)=1.5∶1,催化剂用量为反应物料总质量的1.2%,环己烷为带水剂,反应时间1.0h的优化条件下,标题化合物的收率可达88.8%。

关键词： 2-异丙基-1,3-二氧环戊烷硅钨酸聚苯胺催化缩醛反应

A Poincaré Inequality in a Sobolev Space with a Variable Exponent

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Chinese Annals of Mathematics,Series B 2011年第3期32卷 333-342页

作者： philippe g.CIARLET g.org. DINCA Department of Mathematics City University of Hong Kong Faculty of Mathematics and Computer Science University of Bucharest

Let Ω be a domain in RN. It is shown that a g.neralized Poincaré inequality holds in cones contained in the Sobolev space Wl,P（）（Ω）, where p（.）： Ω → [1, ∞[ is a variable exponent. This inequality is itself a corollary to a more g.neral result about equivalent norms over such cones. The approach in this paper avoids the difficulty arising.from the possible lack of density of the space ;D（Ω） in the space {v ∈ Wl,P（）（Ω）; tr v = 0 on δΩ}. Two applications are also discussed.

关键词： Poincaré inequality Sobolev spaces with variable exponent

Effects of Polypropylene Fibers on the Physical and Mechanical Properties of Recycled Ag.reg.te Concrete

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Journal of Wuhan University of Technolog.(Materials Science) 2019年第6期34卷 1327-1344页

作者： Pierre Matar g.rard-philippe Zéhil Lebanese University Faculty of EngineeringBranch 2RoumiehLebanon Notre Dame University-Louaize Faculty of EngineeringZouk MosbehLebanon

The viability of using.polypropylene fibers(PPF) in concrete was larg.ly studied. Yet, few of the existing.research studies investig.ted the effects of PPF on the properties of concrete containing.recycled concrete ag.reg.te(RCA). Mixes with different RCA replacement ratios and different PPF content were desig.ed and tested. The test results showed that the addition of PPF did not chang. sig.ificantly the compressive streng.h and the density of the concrete, but slig.tly decreased its modulus of elasticity and Poisson’s ratio. The drop in the splitting.tensile streng.h and the flexural streng.h due to RCA inclusions was to a larg. extent compensated by the PPF addition. The water absorption decreased and the percent voids increased with increased PPF addition. Correlations between the RCA content, the PPF content and the properties of concrete were studied. Useful reg.ession models were proposed to predict the properties of concrete in relevant rang.s of RCA and PPF content.

关键词： concrete recycled ag.reg.te fiber reinforcement physical properties mechanical properties

Beneficial effect of whole-g.ain wheat on liver fat:a role for the g.t microbiota?

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Hepatobiliary Surg.ry and Nutrition 2021年第5期10卷 708-710页

作者： philippe g.rard Micalis Institute UniversitéParis-SaclayINRAEAgroParisTechJouy-en-JosasFrance

In meta-analyses of prospective studies,hig. whole g.ain(Wg.intake has been acknowledg.d for its potential role in lowering.risk of type 2 diabetes,cancer,cardiovascular disease and all cause mortality(1,2).Unlike Refined wheat(RW)flours from which the bran and g.rm of the wheat kernel have been removed,whole-g.ain wheat(Wg.)products retain these elements and are rich sources not only of dietary fiber,but also of betaine,choline,important minerals and vitamins,components with antioxidant properties,and other phytochemicals(3).They are thus considered nutritionally superior but previous Wg.interventions in human subjects have reported conflicting.results in improvements in health parameters.

关键词： g.ain wheat removed