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391.
Alizadeh Pahlavani M. R. Mohammadpour H. A. Shoulaie A. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2010,38(2):113-120
392.
We present a summary of methods based on semidefinite programming for estimating arrival rate of nonhomogeneous Poisson processes from a finite set of observed data. Both one-dimensional time dependent, and multi-dimensional time and location dependent rates are considered. The arrival rate is a nonnegative function of time (or time and location). We also assume that it is a smooth function with continuous derivatives of up to certain order k. We estimate the rate function by one or multi-dimensional splines, with the additional condition that the underlying rate function is nonnegative. This approach results in an optimization problem over nonnegative polynomials, which can be modeled and solved using semidefinite programming. We also describe a method which requires only linear constraints. Numerical results based on e-mail arrival and highway accidents are presented. 相似文献
393.
Jocelyn J. Tindale Kurtis D. Hartlen Abdolhamid Alizadeh Prof. Mark S. Workentin Prof. Paul J. Ragogna Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(30):9068-9075
The synthesis and characterization of several compounds representing a new class of multitask‐specific phosphonium ionic liquids that contain a maleimide functionality is reported. The maleimide moiety of the ionic liquid (IL) is shown to undergo Michael‐type additions with substrates containing either a thiol or amine moiety, thus, serving as a template to introduce wide structural diversity into the IL. Multitask‐specific ILs are accessible by reaction of the maleimide with Michael donors that are capable of serving some function. As a model example to illustrate this concept, a redox active ferrocenyl thiol was incorporated and examined by cyclic voltammetry. Because the maleimide moiety is highly reactive to additions, the task‐specific ionic liquids (TSILs) are prepared as the furan‐protected Diels–Alder maleimide. The maleimide moiety can then be liberated when required by simple heating. 相似文献
394.
Glasses in the system 5In2O3·94Na2B4O7 were fabricated via melt quenching technique. The amorphous nature of the quenched glasses was confirmed by X‐ray powder diffraction studies, and the infrared spectra of the glasses show no boroxol ring formation in the structure of these glasses. Differential thermal analysis is shown glass transition temperature 696°C and crystallization temperature 1151°C. A cerium‐zirconium mixed oxide Ce0.75Zr0.25O2 and Ho‐doped cerium‐zirconium mixed oxide were obtained by solid‐state method. Then glass powder and Ho‐doped cerium‐zirconium mixed oxide were mixed. The mixture was heated in a crucible. The glass‐ceramic sample was obtained by pouring the melts on stainless steel. Obtained samples were annealed at 450°C for 1 h to remove thermal strain. Differential thermal analysis for glass‐ceramic sample is shown glass transition temperature 668°C and crystallization temperature 1159°C. The scanning electron microscopy study for glass‐ceramic indicates that the crystallized glass consists of rod‐like crystals with average diameter of about 38 nm dispersed in the glassy regions. 相似文献
395.
R. Alizadeh 《Linear algebra and its applications》2009,430(1):574-119
Let A be a unital associative ring and M be a 2-torsion free A-bimodule. Using an elementary and constructive method we show that every Jordan derivation from Mn(A) into Mn(M) is a derivation. 相似文献
396.
A novel unsymmetrical diamine monomer containing triaryl imidazole pendant group, 4-[4-(4,5-diphenyl-1H-imidazol-2-yl)phenoxy] benzene-1,3-diamine (DAI), was successfully synthesized via aromatic substitution reaction of 1-chloro-2,4-dinitrobenzene with 4-(4,5-diphenyl-1H-imidazol-2-yl)phenol, followed by palladium-catalyzed hydrazine reduction. The diamine monomer DAI polymerized with commercial available dianhydrides such as benzophenone tetracarboxylic dianhydride (BTDA), pyromellitic dianhydride (PMDA) and bicyclo[2.2.2]-oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BCDA) by using two step synthetic methods to obtain corresponding polyimides (PIs). PIs had inherent viscosity of 0.42-0.51 dL/g and exhibited excellent solubility in aprotic polar solvents such as N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), pyridine and methyl sulfoxide (DMSO). PIs showed high glass transition temperatures between 230 and 320 °C, and they were fairly stable up to a temperature above 300 and 450 °C depending on the dianhydride monomer used for the PIs preparation. 相似文献
397.
Abdolali Alizadeh Sadegh Rostamnia Nasrin Zohreh Reza Hosseinpour 《Tetrahedron letters》2009,50(14):1533-322
A facile and direct synthetic entry to rhodanine derivatives via the three-component coupling of carbon disulfide, primary amines, and acetylenic esters under neutral conditions in water is reported. 相似文献
398.
New unsymmetrical diamine monomer containing triaryl imidazole pendent group,4-[4-(4,5-diphenyl-1H-imidazol-2-yl)phenoxy] -1,3-benzenediamine,was synthesized via aromatic substitution reaction of 1-chloro-2,4-dinitrobenzene with 4-(4,5- diphenyl-1H-imidazol-2-yl)phenol,followed by palladium-catalyzed hydrazine reduction.This new monomer was further confirmed by FT-IR,~1H NMR and ~(13)C NMR.Novel polyamides having pendant triaryl imidazole group were prepared by the phosphorylation polycondensation of fou... 相似文献
399.
This article reviews a new developing method in the field of metal oxide reduction in chemical and metallurgical processes, which uses methane as a reducing agent. Commonly, coal is used as the reducing agent in the reduction of metal oxide and other inorganic materials; Metal producing factories are among the most intensive and concentrated source of greenhouse gases and other pollutants such as heavy metals, sulfur dioxide and fly ash. Thermodynamically, methane has a great reducing capability and can be activated to produce synthesis gas over a metal oxide as an oxygen donor. Metal oxide reduction and methane activation, two concurrent thermochemical processes, can be combined as an efficient and energy-saving process; nowadays this kind of technologies is of great importance. This new reduction process could improve energy efficiencies and significantly decrease greenhouse gas emission compared to the conventional process; furthermore, the produced gases are synthesis gas that is more valuable than methane. In this paper, thermodynamic studies and advantages of this promising method were discussed. The major aim of this article is to introduce methane as a best and environmentally friendly reducing agent at low temperature. 相似文献
400.
Adibi H Rashidi A Khodaei MM Alizadeh A Majnooni MB Pakravan N Abiri R Nematollahi D 《Chemical & pharmaceutical bulletin》2011,59(9):1149-1152
In this research, synthesis, antimicrobial and antioxidant activities of a series of catecholthioethers having benzoxazole and tetrazole moieties are described. Antimicrobial activity was evaluated by minimum inhibitory concentration (MIC) assay. The synthesized compounds were tested in vitro against three Gram-positive bacteria including Staphylococcus aureus (clinical isolated), Staphylococcus aureus ATCC 25922, Enterococcus faecium (clinical isolated), and two Gram-negative bacteria including Klebsiella pneumoniae (clinical isolated) and Pseudomonas aeruginosa 27853 and the yeast Candida albicans in comparison with control drugs. Microbiological results indicated that the synthesized compounds possessed a broad spectrum of activity against the tested microorganisms at MIC values between 4-256 μg/ml. This shows compounds having tetrazole moiety were the most active against Gram-negative strains, whereas compounds having benzoxazole moiety were more active against Gram-positive ones. Also both of them showed significant antifungal activity against Candida albicans and had lower activity than the compared control drugs (Sulfamethoxazole and Fluconazole). The antioxidant activity was assessed using two methods, including, 1,1-biphenyl-2-picrylhydrazyl (DPPH) radical scavenging, and reducing power assays. Some of the catecholthioether derivatives showed antioxidant activity more than Trolox and butylated hydroxyanisole (BHA) as reference antioxidants. 相似文献