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Recent Advances in Superplastic Intermetallics

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Acta Metallurgica Sinica(English Letters) 1995年第Z1期8卷 405-417页

作者： NIEH Tai-Gang WADSWORTH Jeffrey (Lawrence Livermore National Laboratory, Livermore, ca 94550, USA) Lawrence Livermore National Lab Livermore United States

Superplasticity in intermetallic alloys is reviewed. Intermetallics which have been demonstrated to be superplastic include nickel-based (Ni_3Al, Ni_3Si), titanium-base (Ti_3Al, TiAl), and iron-base (Fe_3Al, FeAl) alloys. These alloys are primarily finegrained, two phase materials. But, superplasticity was also observed in some iron-base alloys which were in coarsegrained conditions. These alloys behave like Class I solid solution. The superplastic deformation mechanisms as well as microstructural characteristics are discussed. The superplastic forming of intermetallics is also briefly addressed.

关键词： Superplasticity microstructure grain size boundary sliding

Changes in expression of inhibitory substances in the intramural neurons of the stomach following streptozotocininduced diabetes in the pig

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World Journal of Gastroenterology 2017年第33期23卷 6088-6099页

作者： Michal Bulc Katarzyna Palus Lukasz Zielonka Magdalena Gajecka Jaroslaw całka Department of Clinical Physiology Faculty of Veterinary Medicine University of Warmia and Mazury Department of Veterinary Prevention and Feed Hygiene Faculty of Veterinary MedicineUniversity of Warmia and Mazury in Olsztyn

AIM Influence of chronic hyperglycemia on chemical coding of enteric neurons in stomach using pig as a model for human diabetic *** Ten pigs were divided into two groups: diabetic(D group,n = 5) and control(C group,n = 5). Pigs constituting the experimental group were given streptozotocin(150 mg/kg). Animals were euthanized six weeks after the induction of diabetes. The samples of stomach were collected from animals of both groups. The cryostat sections were processed for double immunofluorescence staining using primary antisera directed towards pan-neuronal marker(Hu C/D) proteins and/or neuronal isoform of nitric oxide synthase(n NOS),vasoactive intestinal peptide(VIP) and galanin(GAL). RESULTS In the control group in the myenteric ganglia(MG) of the corpus we have noted 22.28% ± 1.19% of n NOS positive neurons,while in diabetic group we have found 40.74% ± 2.22% of n NOS immunoreactive perikarya(increase by 82.85 %). In turn in the pylorus we have observed 15.91% ± 0.58% n NOS containing neurons in control animals and 35.38% ± 1.54% in the diabetes group(increase by 122.37%). In the MG of the antrum and submucosal ganglion(SG) in the corpus hyperglycemia did not cause statistically significant changes. With regard to VIP-positive cell bodies in the antrum MG in the control animals we have noted 18.38 ± 1.39% and 40.74% ± 1.77% in the experimental group(increase by 121.65%). While in the corpus we have observed 23.20% ± 0.23% in the control and 30.93% ± 0.86% in the diabetes group(increase by 33.31%). In turn in the pylorus VIP positive cells bodies constituted 23.64% ± 1.56% in the control group and 31.20% ± 1.10% in the experimental group(increase by 31.97%). In the submucosal ganglion in the corpus we have noted 43.61% ± 1.06% in the control animals and 37.00% ± 1.77% in the experimental group(decrease by 15.15%). Expression of GAL-positive perikarya showed statistically significant changes only in the MG of the antrum and pylorus. In the antr

关键词： Immunohistochemistry Inhibitory neurons Streptozotocin Hyperglycemia Pig

北祁连山高压变质带的变形和变质特征及其对俯冲带折返的意义

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岩石学报 2009年第9期25卷 2235-2246页

作者：曹毅宋述光 ca0 Peking Univ MOE Key Lab Orogen Belts & Crustal Evolut Dept Geol Beijing 100871 Peoples R China

北祁连造山带是早古生代大洋板块"冷"俯冲的典型地区,形成了一系列高压低温变质的岩石组合。基性榴辉岩是俯冲洋壳变质的产物,根据其结构构造特征可以划分为(1)粒状榴辉岩,峰期变质矿物组合为Grt+Omp+Phn+Rut±Lws,硬柱石呈包裹体和假... 详细信息

北祁连造山带是早古生代大洋板块"冷"俯冲的典型地区,形成了一系列高压低温变质的岩石组合。基性榴辉岩是俯冲洋壳变质的产物,根据其结构构造特征可以划分为(1)粒状榴辉岩,峰期变质矿物组合为Grt+Omp+Phn+Rut±Lws,硬柱石呈包裹体和假象分布于石榴石内,变质温压条件T=465～508℃,p=2.30～2.60GPa。(2)片状榴辉岩,岩石具片状构造,其共生矿物组合Omp+Czo/Ep+Phn+Gln构成透入性面理S_1和线理L_1,以及宏观和显微同斜褶皱F_1。其峰期变质温压条件为T=466～510℃,P=1.9～2.2GPa。(3)蓝片岩相退化变质榴辉岩,蓝片岩相变质矿物Gln+Ep+Phn±Ab强烈交代榴辉岩相矿物,并发生强烈D_2期变形作用,岩石形成明显的透入性面理S_2和线理L_2,以及同斜剪切褶皱F_2。蓝闪石和多硅白云母线理的统计揭示D_2期变形以斜向走滑剪切为主,与D_1期变形的榴辉岩的运动学特征大体相似。D_2同变质的温压条件为T=422～487℃,P=1.15～1.37GPa。高压变质带晚期的绿片岩相叠加和D_3期变形,形成透入性面理S_3和线理L_3,其运动特征为近于垂直构造线的逆冲剪切。结合榴辉岩变形特征,变质温压条件和同位素年代学资料,我们认为退变质的强弱与变形程度有密切关系。峰期变质后的榴辉岩经过早期绿帘石榴辉岩相到蓝片岩相斜向走滑剪切,和晚期绿片岩相逆冲,在泥盆纪早期快速折返的出露地表。

关键词：北祁连山高压变质带变形变质特征俯冲带折返 implications 榴辉岩相峰期变质温压条件 mineral assemblage 蓝片岩相 North Qilian Mountains isotopic geochronology 走滑剪切线理绿片岩相矿物组合变质矿物 movement Early Paleozoic

Three-dimensional mixed convection stagnation-point fow past a vertical surface with second-order slip velocity

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Applied Mathematics and Mechanics(English Edition) 2023年第4期44卷 641-652页

作者： A.V.ROSca N.C.ROSca I.POP Department of Statistics-Forecasts-Mathematics Faculty of Economics and Business AdministrationBabes-Bolyai UniversityCluj-Napoca 400084Romania Department of Mathematics Faculty of Mathematics and Computer ScienceBabes-Bolyai UniversityCluj-Napoca 400084Romania Academy of Romanian Scientists 3 Ilfov StreetBucharest 050044Romania

This study is concerned with the three-dimensional(3D)stagnation-point for the mixed convection flow past a vertical surface considering the first-order and secondorder velocity *** the authors’knowledge,this is the first study presenting this very interesting *** partial differential equations for the flow problem are transformed into nonlinear ordinary differential equations(ODEs)by using appropriate similarity *** ODEs with the corresponding boundary conditions are numerically solved by utilizing the bvp4c solver in MATLAB programming *** effects of the governing parameters on the non-dimensional velocity profiles,temperature profiles,skin friction coefficients,and the local Nusselt number are presented in detail through a series of graphs and ***,it is reported that the reduced skin friction coefficient decreases for the assisting flow situation and increases for the opposing flow *** numerical computations of the present work are compared with those from other research available in specific situations,and an excellent consensus is *** exciting feature for this work is the existence of dual *** important remark is that the dual solutions exist for both assisting and opposing flows.A linear stability analysis is performed showing that one solution is stable and the other solution is not *** notice that the mixed convection and velocity slip parameters have strong effects on the flow *** effects are depicted in graphs and discussed in this *** obtained results show that the first-order and second-order slip parameters have a considerable effect on the flow,as well as on the heat transfer characteristics.

关键词： three-dimensional(3D)mixed convection flow stagnation point flow first-order slip velocity second-order slip velocity numerical solution stability analysis

Total synthesis of(+)-lentiginosine via a key Au catalysis

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Science China Chemistry 2010年第1期53卷 113-118页

作者： CUI Li & ZHANG LiMing Department of Chemistry & Biochemistry,University of california,Santa Barbara,ca 93106,USA Department of Chemistry & Biochemistry University of California Santa Barbara USA

Total syntheses of(+)-lentiginosine and its 8a-epimer using a gold-catalyzed oxidative cyclization as the key step were *** gold chemistry,reported previously in a 4+2 synthesis of piperidin-4-ones,tolerates functiona... 详细信息

关键词： gold total synthesis cyclization oxidation alkaloid

Photosynthetic Behaviour and Mineral Nutrition of Tamarix gallica Cultivated Under Aluminum and NaCl Combined Stress

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Phyton-International Journal of Experimental Botany 2019年第3期88卷 239-252页

作者： Dhouha Belhaj Sghaier Insaf Bankaji Sylvia Pedro Isabel caçador Noomene Sleimi LR.RME-Ressources Matériaux et EcosystèmesFaculty of Sciences of BizerteUniversity of Carthage7021 JarzounaBizerteTunisie MARE-Marine and Environmental Sciences Centre Faculty of Sciences of the University of LisbonPortugal

The lack of knowledge of plant tolerance and differential response to aluminum(Al)encouraged many researchers,in the last decade,to elucidate Al toxicity and tolerance *** current study reported the impact of Al,a toxic element with negative effects on plant growth and development,in halophytic plant Tamarix *** were subjected to different Al concentrations(0,200,500 and 800μM)with or without NaCl(200 mM)***,photosynthesis and mineral content were *** stress had a significant decrease on shoots’biomass production between 19 to 41%,and a little variation on chlorophyll content and photosynthetic efficiency(Fo,Fm,Fv fluorescence’s and Fv/Fm).Furthermore,the Al-treatments did not affect significantly the content of potassium,calcium,and magnesium in different plant parts,whereas NaCl addition to the medium induced a decrease in these elements’*** results have shown that *** is able to accumulate the high levels of Al in shoots and roots,6288μg.g^(-1) DW and 7834μg.g^(-1) DW *** is considered as a hyperaccumulator plant of *** addition,Na+contents in shoots and roots exceed 23000μg.g^(-1) ***,*** presents a high tolerance at the same time to Al and NaCl phytotoxicity,so it is interesting to use in phytoremediation programs.

关键词： Halophyte tolerance combined stress photosynthetic pigments chlorophyll fluorescence Al-accumulation nutrients uptake

Rate of convergence for the Legendre pseudospectral optimal control of feedback linearizable systems

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控制理论与应用（英文版） 2010年第4期8卷 391-405页

作者： Wei KANG (Department of Applied Mathematics,Naval Postgraduate School,Monterey ca 93943,USA) Department of Applied Mathematics Naval Postgraduate School Monterey USA

Pseudospectral （PS） computational methods for nonlinear constrained optimal control have been applied to many industrial-strength problems,notably,the recent zero-propellant-maneuvering of the international space station performed by *** this paper,we prove a theorem on the rate of convergence for the optimal cost computed using a Legendre PS *** addition to the high-order convergence rate,two theorems are proved for the existence and convergence of the approximate *** to existing work on PS optimal control as well as some other direct computational methods,the proofs do not use necessary conditions of optimal ***,we do not make coercivity type of *** a result,the theory does not require the local uniqueness of optimal *** addition,a restrictive assumption on the cluster points of discrete solutions made in existing convergence theorems is removed.

关键词： Computational optimal control Pseudospectral method Convergence

A Formula for the Non-integer Powers of the Laplacian

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Acta Mathematica Sinica,English Series 1999年第1期15卷 21-24页

作者： Zhengxu HeDepartment of Mathematics,University of california,San Diego,La Jolla,ca 92093-0112,USA Department of Mathematics University of California San Diego La Jolla USA

We provide an elementary formula for the non-integer powers of the Laplace operator in the Euclidean *** formulas are helpful in establishing the elliptic nature of some pseudo- differential operators arising from the... 详细信息

关键词： Laplacian Power of Laplacian

Pisco grape pomace:Iron/copper speciation and antioxidant properties,towards their comprehensive utilization

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Food Bioscience 2022年第3期47卷 1213-1221页

作者： Fátima Rodríguez-Ramos Raúl cañas-Sarazúa Vilbett Briones-Labarca Departamento de Ingeniería en Alimentos Universidad de La SerenaAv.Raúl Bitrán Nachary 1305Box 5991720010La SerenaChile

The pisco and wine industry produces hundreds of tons of grape pomace each year in Chile,generating environmental problems,and demanding urgent strategies for its *** aim of this work was to study the pisco grape pomace based on a physicochemical characterization,an iron/copper speciation analysis,and the optimization for polyphenols recovery,establishing the polyphenolic profile,antioxidant properties,and the Fe^(2+)/Cu^(2+) chelating activity,to promote their revalorization as an ingredient with potential application in the food *** chemical characterization showed mainly high values for crude protein(15.36%dw)and potassium(9240.66 mg/kg).The Fe/Cu speciation depicted that iron and copper soluble forms in pisco pomace flour represented 70.57%and 52.18%,respectively,regarding total *** optimized extract showed mainly pyrogallol,catechin and epicatechin,with concentrations of 1078.43±60.14μg/g,883.20±7.57μg/g and,751.76±23.04μg/g,respectively,with a relevant antioxidant capacity by Oxygen Radical Absorbance capacity(ORAC)of 1402.15μmol TE/g dw GPE and,a better chelating ability to complex Fe^(2+) than Cu^(2+).The pisco pomace was for the first time chemically characterize,showing it as a potential source of minerals and antioxidant biocompounds,making it a good candidate for nutritional applications,as a rich source of organic matter or even could be potentially utilized to produce value-added commodities,toward a circular economy.

关键词： Pisco grape pomace Polyphenols Chemical speciation analysis Antioxidant capacity Metal chelating ability