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Tameness and Artinianness of Graded Generalized Local Cohomology Modules

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Algebra Colloquium 2015年第1期22卷 131-146页

作者： M. Jahangiri n. shirmohammadi sh. Tahamtan Faculty of Mathematical sciences and Computer Kharazmi University rlbhran Iran School of Mathematics Institute for Research in Fundamental Sciences (IPM) P.O. Box 19395-5749 Tehran Iran School of Mathematics Institute for Research in Fundamental Sciences (IPM) P.O. Box 19395-5749 rlbhran Iran Department of Mathematics University of Tabriz Tabriz Iran Islamic Azad University Borujerd Branch Boroujerd Iran

Let R = ⊙n〉0 Rn be a standard graded ring, a ∩ ⊙n〉0 Rn an ideal of R, and M, n two finitely generated graded R-modules. This paper studies the homogeneous components of graded generalized local cohomology modules. We show that for any i 〉 0, the n-th graded component Hiα（M, n）n of the i-th generalized local cohomology module of M and n with respect to a vanishes for all n 〉〉 0. Some sufficient conditions are pro- posed to satisfy the equality sup{end（Hiα （M, n）） [ i _〉 0} = sup{end（HiR＋（M, n））｜ i 〉 0}. Also, some sufficient conditions are proposed for the tameness of Hiα（M, n） such that i = fRα＋（M,n） or i = cdα（M,g）, where fRα＋（M,n） and cdα（M,g） denote the R＋- finiteness dimension and the cohomological dimension of M and n with respect to a, respectively. Finally, we consider the Artinian property of some submodules and quotient modules of Hjα（M, n）, where j is the first or last non-minimax level of Hiα（M, n）.

关键词： graded rings and modules generalized local cohomology Artinian modules,tameness

Sorption of certain lanthanides by kieselguhr loaded with Cyanex 572 from sulfate medium

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Journal of Rare Earths 2020年第3期38卷 299-305页

作者： sh.sh.Emam M.S.Gasser n.E.El-Hefny W.H.Mahmoud H.F.Aly Hot Laboratories Centre Atomic Energy AuthorityCairo 13759Egypt Department of chemistry Faculty of ScienceAin Shams UniversityCairoEgypt

Kieselguhr for chromatography was loaded with Cyanex 572 extractant and characterized using X-ray diffraction(XRF),scanning electron microscopy(SEM),Fourier transform infra-red(FT-IR),and thermal *** of some heavy lanthanides together with yttrium by the prepared kieselguhr/Cy-572 sorbent was investigated by batch experiment in terms of initial metal ions concentrations,volume to solid mass ratio(V/m),sulfuric acid concentration as well as *** sorption equilibrium of Cy-572 loaded kieselguhr was satisfactorily explained by the pseudo second-order kinetic model and Langmuir isotherm ***,the values of thermodynamic parameters △G°,△H°,and △S°at25℃of the studied metal ions show that the process is spontaneous and endothermic in nature.2.0 mol/L HnO3 is promising to desorb these metal ions.

关键词： Sorption Cyanex 572 Lanthanides Kieselguhr Sulfate medium Rare earths

Experimental and numerical study on plasma nitriding of AISI P20 mold steel

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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 1065-1075页

作者： n.nayebpashaee H.Vafaeenezhad sh.Kheirandish M.Soltanieh Materials Processing Simulation Laboratory(MPS-LAB) School of Materials and Metallurgical EngineeringIran University of Science and Technology(IUST) School of Materials and Metallurgical Engineering Iran University of Science and Technology(IUST)

In this study, plasma nitriding was used to fabricate a hard protective layer on AISI P20 steel, at three process temperatures（450℃, 500℃, and 550℃） and over a range of time periods（2.5, 5, 7.5, and 10 h）, and at a fixed gas n2：H2 ratio of 75vol%：25vol%. The morphology of samples was studied using optical microscopy and scanning electron microscopy, and the formed phase of each sample was determined by X-ray diffraction. The elemental depth profile was measured by energy dispersive X-ray spectroscopy, wavelength dispersive spectroscopy, and glow dispersive spectroscopy. The hardness profile of the samples was identified, and the microhardness profile from the surface to the sample center was recorded. The results show that ε-nitride is the dominant species after carrying out plasma nitriding in all strategies and that the plasma nitriding process improves the hardness up to more than three times. It is found that as the time and temperature of the process increase, the hardness and hardness depth of the diffusion zone considerably increase. Furthermore, artificial neural networks were used to predict the effects of operational parameters on the mechanical properties of plastic mold steel. The plasma temperature, running time of imposition, and target distance to the sample surface were all used as network inputs; Vickers hardness measurements were given as the output of the model. The model accurately reproduced the experimental outcomes under different operational conditions; therefore, it can be used in the effective simulation of the plasma nitriding process in AISI P20 steel.

关键词： tool steel plasma nitriding sputtering neural networks

Comparative studies on Y(Ⅲ)and Dy(Ⅲ)extraction from hydrochloric and nitric acids by Cyanex 572 as a novel extractant

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Journal of Rare Earths 2018年第12期36卷 1342-1350页

作者： n.E.El-Hefny M.S.Gasser sh.sh.Emam W.H.Mahmoud H.F.Aly Hot Laboratories Centre Atomic Energy Authority Faculty of Science Ain Shams University

Extraction of Y(III) and Dy(III) from hydrochloric and nitric acids by Cy-572 in kerosene was studied. The factors affecting the extraction were separately investigated. The stoichiometry of the extracted species was deduced on the basis of slope analysis method. Evaluation of extraction equilibrium and stripping investigation was studied as well as saponification effect of Cy-572. The composition of the extracted metal species in the organic phase was found to be [MA·(HA)] for Y(III) or Dy(III) in both media.1.0 mol/L HCI is the best stripping agent for each metal ion from the studied acidic media in one *** Cy-572 does not exhibit any selectivity towards the extraction of Y(III) or Dy(III) from both HCI and HnOsolutions. Based on the obtained results, the data were compared and the separation feasibility between lanthanides and Y(III) in the two media was discussed.

关键词： Extraction Cyanex-572 Yttrium Lanthanides Separation factor Saponification

Invertebrate Iridovirus Modulation of Apoptosis

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Virologica Sinica 2009年第4期24卷 295-304页

作者： Trevor Williams nilesh S. chitnis sh.n L. Bilimoria Instituto de Ecología AC Abramson Cancer Center and Department of Cancer Biology University of Pennsylvania Department of Biological Sciences The Center for Biotechnology and Genomics Texas Tech University

Programmed cell death （apoptosis） is a key host response to virus infection. Viruses that can modulate host apoptotic responses are likely to gain important opportunities for transmission. Here we review recent studies that demonstrate that particles of Invertebrate iridescent virus 6 （IIV-6）（Iridoviridae, genus Iridovirus）, or an IIV-6 virion protein extract, are capable of inducing apoptosis in lepidopteran and coleopteran cells, at concentrations 1000-fold lower than that required to shut-off host macromolecular synthesis. Induction of apoptosis depends on endocytosis of one or more heat-sensitive virion component（s）. Studies with a JnK inhibitor （SP600125） indicated that the JnK signaling pathway is significantly involved in apoptosis in IIV-6 infections of choristoneurafumiferana cells. The genome of IIV-6 codes for an inhibitor of apoptosis iap gene （193R） that encodes a protein of 208 aa with 15% identity and 28% similarity in its amino acid sequence to IAP-3 from Cydia pomonella ganulovirus （CpGV）. Transcription of IIV-6 iap did not require prior DnA or protein synthesis, indicating that it is an immediate-early class gene. Transient expression and gene knockdown studies have confirmed the functional nature of the IIV-6 lap gene. We present a tentative model for IIV-6 induction and inhibition of apoptosis in insect cells and discuss the potential applications of these findings in insect pest control.

关键词： Apoptosis Invertebrate iridescent virus 6 Induction by endocytosis Inhibition of apoptosis (iap) gene Iridoviridae JnK pathway involvement.

Effect of tritium reduction in determining energy gain by using R-matrix method direct laser fusion in D-T reaction

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nuclear Science and Techniques 2007年第3期18卷 129-136页

作者： S.n.HOSSEInI MOTLAGH sh.S.MOHAMADY M.Kh.MORADKHAnI R.shAMSI Department of Physics Iran University of Science and Technology IranDepartment of PhysicsIran University of Science and Technology IranDepartment of PhysicsIran University of Science and Technology IranDepartment of Industrial EngineeringMazandaran University of Science and Technology Iran

The laser fusion criterion is known as the ρR-Criterion, also called high-gain condition. This parameter is temperature dependent and can be calculated by R-matrix method. This method is applied for determining improved fusion cross-section for the reactions T(d,n)4He, 3He(d,p)4He, D(d,p)T, D(d,n)3He. In this paper the time dependent reaction rate equations for fusion reaction T(d,n)4He are solved and by using the obtained results we computed the fu- sion power density, energy gain versus temperature and ρR-parameter. The obtained results show that a suitable com- bination may be a deuterium fraction fD=0.65 and fT=0.35 which would lead 30% reduction in the tritium content of the fuel mixture, and this choice would not change the energy gain value very much. Finally, the obtained energy gain for D-T reaction by using R-matrix is in good agreement with other theories.

关键词：氘氚反应激光聚合等离子体交叉断面

Dry Sliding Oxidative Wear in Plain Carbon Dual Phase Steel

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Journal of Iron and Steel Research International 2007年第4期14卷 43-48页

作者： V Abouei H Saghafian sh Kheirandish Department of Metallurgy and Materials Engineering Iran University of Science and TechnologyNarmak 16844TehranIran

To investigate the tribological potential of the dual phase （DP） steel as a wear resistant material, the wear and the friction characteristics of this steel, which consists of hard martensite islands embedded in a ductile ferrite matrix, have been investigated and compared with those observed in plain carbon hardened （H） steel that has the same carbon content of 0.2%. Dry sliding wear tests have been carried out using a pin-on-disk wear testing machine at different normal loads of 21.3 n, 28. 5 n, 35.7 n, and 42.6 n and at a constant sliding velocity of 1.20 m/s. The analysis of surface and wear debris of samples showed that the wear mechanism was mainly mild oxidative. The friction and the wear rate of the H steel and the DP Steel have been explained with respect to the microstructure and the wear mechanism.

关键词： dual phase steel wear microstructure heat treatment

Essential commutant of analytic Toeplitz operators

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chinese Science Bulletin 1997年第7期42卷 548-552页

作者： Ding, XH Sun, sh Department of Mathematics Sichuan Union University Chengdu China

LET Bn be the unit ball of Cn. The n-dimensional vector space over the complex field C, Sn=（?）Bn is the boundary of Bn. We use σ to denote the unique rotation-invariant probability measure on Sn. The Lebesgue space... 详细信息

关键词： Toeplitz operators inner function essential commutant.

Fluorescence Quenching and Depolarization Studies on Segmental Motion of Poly (n, n-dimethylacrylamide)

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chinese chemical Letters 1997年第8期8卷 719-720页

作者： Zhu, CY Wu, sh Li, LR nAnKAI UnIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

A new polymer, poly(n, n-dimethylacrylamide), labeled with acenaphthylene has been synthesized. The rotational relaxation time of this polymer has been studied using steady state fluorescence depolarization measuremen... 详细信息

关键词： Fluorescence Quenching and Depolarization Studies on Segmental Motion of Poly n-dimethylacrylamide