检索结果-南通市图书馆

Chinese Journal of Chemistry 2011年第6期29卷 1290-1293页

作者： Gholivand, Khodayar zare, karim Jafari, Hadi Adibi, Hadi Department of Chemistry Science and Research Branch Islamic Azad University Tehran Iran Department of Medicinal Chemistry Faculty of Pharmacy Kermanshah University of Medical Sciences Kermanshah 67145-1673 Iran

Borax/phosphorous oxychloride （BPO） efficiently catalyzes the preparation of 1,5-benzodiazepine derivatives of o-phenylenediamines and ketones in solvent-free and solution conditions. The reaction proceeds efficiently under ambient conditions giving excellent yields of the products. This new protocol allows the recycling of catalyst with no loss in its potency.

关键词： 1,5-benzodiazepine o-phenylenediamine borax phosphorus oxychloride

Interfacial synthesis and properties of L-lysine-derived optically active poly(ester-imide)s

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第5期22卷 607-610页

作者： Saeed Zahmatkesh Ali Reza Alborzi Javad Sadeghi karim zare Department of Science Payame Noor University(PNU)TehranIran Department of Chemistry Islamic Azad University FirouzabadFarsIran

L-Lysine hydrochloride was transformed to ethyl L-lysine *** salt was reacted with trimellitic anhydride to yield the corresponding diacid（1）.Intertacial polycondensation results novel poly（ester-imide）s（PEI_（a-i））.These polymers have inherent viscosities in the range of 0.23-0.47 dl g^（-1）,display optical activity,and are readily soluble in polar aprotic *** start to decompose（T_（10%）） above 350℃and display glass-transition temperatures at 100.42-172.81℃.All of the above polymers were fully characterized by UV,FT-IR and ~1H NMR spectroscopy,elemental analysis,TGA,DSC,inherent viscosity measurement and specific rotation.

关键词： Chiral Optically active L-Lysine Poly(ester-imide) Interfacial polymerization

Complexation of Sm^(3+) and pamidronate: A DFT study

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2015年第3期33卷 310-319页

作者： Masoud Arabieh Mohammad Hassan Khodabandeh Mohammad Hossein karimi-Jafari Carlos Platas-Iglesias karim zare Computational Chemistry Laboratory NSTRI 11365-8486 Tehran Iran Department of Chemistry Faculty of Science Shahid Beheshti University G.C. Evin 19839-63113 Tehran Iran Department of Bioinformatics Institute of Biochemistry and Biophysics University of Tehran 13145-1384 Tehran Iran Departamento de Química Fundamental Universidade da Coru?a Campus da Zapateira-Rúa da Fraga 10 15008 A Coru?a Spain

We reported a quantum mechanical study of the complexes formed between Sm3＋ and the bisphosphonate ligand pamidronate in aqueous solution. According to available experimental p K a values pamidronate was expected to exist in aqueous solution, at physiologically relevant p H, in its di- and tri-protonated forms（denoted by H3 L and H2L）. The most stable structures of the ligands and Sm3＋ complexes were found by using a detailed analysis of the conformational space with semiempirical and DFT methods. The results showed that both H2 L and H3 L bisphosphonates acted as a tridentate ligands in their complexes with Sm3＋. The addition of explicit water molecules to the coordination sphere of the metal not only gave different coordination numbers for H2 L and H3 L complexes（CN=9 and 10）, but also provided different trends in stabilization energies. The results highlighted the importance of considering not only an explicit first coordination shell, but also a second hydration shell, for an adequate description of this type of complexes in aqueous solution.

关键词： samarium radiopharmaceutical bisphosphonates solvent effects rare earths

DFT Study on Thermodynamic Parameters of CO2 Absorption into Aqueous Solution of Aliphatic Amines

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Physics 2014年第6期27卷 672-678,I0003页

作者： Monireh Hajmalek Hossein Aghaie karim zare Mehran Aghaie 伊朗伊斯兰阿扎德大学科学研究部化学系德黑兰伊朗萨伊德比赫什蒂大学理学院化学系德黑兰伊朗伊斯兰阿扎德大学德黑兰分校化学部德黑兰

Using density functional theory （DFT）, the thermodynamic parameters of the CO2 absorp-tion into the aqueous solution of the aliphatic amines including some alkylamines, alka-nolamines, diamines and a type of aminoamide were calculated. The geometry optimiza-tion and the calculation of vibrational frequencies in the gas phase were performed at the B3LYP/6-311＋ G（d,p） level of theory. Moreover, the standard solvation free energies of the studied species were computed upon the solution phase optimized geometries through the latest continuum solvation model （SMD/IEF-PCM） at the HF/6-31G（d） level of theory. With this approach, two important properties of the CO2 absorption into the aqueous so-lutions of the studied amines were evaluated： the acid dissociation constant （pKa） of the parent amines and the standard enthalpy change （ΔH^φabs） related to the CO2 absorption process. A roughly linear relationship was observed between pKa and ΔH^φabs. This finding suggests that a raise in the basicity of an amine leads to an increase in the heat released in CO2 absorption and consequently in the required energy for the regeneration of amine.

关键词： Density functional theory Amine CO2 absorption Heat of absorption SMD solvation model

Prediction of overbreak depth in Ghalaje road tunnel using strength factor

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2018年第4期28卷 671-676页

作者： Ako Daraei Shokrollah zare Civil Engineering Department Soran University School of Mining Petroleum & Geophysics Engineering Shahrood University of Technology

It is well known that the overbreak caused by the blasting damage during tunnel excavation increases costs associated with filling the collapsed area with shotcrete and results in filing of a claim by the contractor. This paper outlines a new approach for prediction the overbreak depth during tunnel construction. Hence, firstly excavation damage zone(EDZ) are determined by average specific charge in each zone. Numerical modelling is used to simulate the EDZ around tunnel boundary and the overbreak depth are calculated by the rock strength factor. The predicted overbreak depth compared with observed field data from a case study. The results show that there exists an approximately up to 40% difference between the prediction and the observed volume of overbreak depth. Therefore, the method can be well used to predict the overbreak depth to estimate more precision of shotcrete and concrete volumes in tunnelling cost during design phase.

关键词： Overbreak Blasting Excavation damaged zone Strength factor Tunneling

Influence of soaking time in deep cryogenic treatment on the microstructure and mechanical properties of low-alloy medium-carbon HY-TUF steel

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2016年第6期23卷 658-666页

作者： Ahmad zare S.R.Hosseini Department of Materials Engineering Maleke-ashtar University of Technology

The influence of soaking time in deep cryogenic treatment on the tensile and impact properties of low-alloy medium-carbon HY-TUF steel was investigated in this study. Microstructural studies based on phase distribution mapping by electron backscatter diffraction show that the deep cryogenic process causes a decrease in the content of retained austenite and an increase in the volume fraction of η-carbide with increasing soaking time up to 48 h. The decrease in the content of retained austenite from ~1.23vol% to 0.48vol% suggests an isothermal martensitic transformation at 77 K. The η-type precipitates formed in deep cryogenic-treated martensite over 48 h have the Hirotsu and Nagakura orientation relation with the martensitic matrix. Furthermore, a high coherency between η-carbide and the martensitic matrix is observed by high-resolution transmission electron microscopy. The variations in macrohardness, yield strength, ultimate tensile strength, and ductility with soaking time in the deep cryogenic process show a peak/plateau trend.

关键词： low alloy steel medium carbon steel cryogenic treatment microstructure mechanical properties fractography

Multicomponent synthesis of dihydropyridines catalyzed by L-proline

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第5期22卷 531-534页

作者： Leila zare Mohammad Nikpassand Department of Organic Chemistry Islamic Azad University-Rasht BranchRashtIran

Multicomponent synthesis of mono and bis 4-substituted-1,4-dihydropyridines from aldehydes,dimedone and ammonium acetate in the presence of an efficient recyclable catalyst,L-proline,in high yield and short reaction t... 详细信息

关键词： Multicomponent Dihydropyridines Dimedone L-Proline

The roles of polymer-graphene interface and contact resistance among nanosheets in the effective conductivity of nanocomposites

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 1941-1956页

作者： Y.zare K.Y.RHEE Department of Mechanical Engineering(BK21 Four) College of EngineeringKyung Hee UniversityYongin 17104Republic of Korea

The effective conductivity of graphene-based nanocomposites is suggested by the characteristics of polymer-filler interfacial areas as well as the contact resistance between the neighboring *** interfacial properties are expressed by the effective levels of the inverse aspect ratio and the filler volume ***,the resistances of components in the contact regions are used to define the contact resistance,which inversely affects the effective *** obtained model is utilized to predict the effective conductivity for some *** discrepancy of the effective conductivity at various ranks of all factors is *** interfacial conductivity directly controls the effective conductivity,while the filler conductivity plays a dissimilar role in the effective conductivity,due to the incomplete interfacial adhesion.A high operative conductivity is also achieved by small contact distances and high interfacial ***,big contact diameters and little tunnel resistivity decrease the contact resistance,thus enhancing the effective conductivity.

关键词： polymer nanocomposite operative conductivity graphene interfacial property contact region

Circuit-theory-based method for transmission fixed cost allocation based on game-theory rationalized sharing of mutual-terms

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2019年第6期7卷 1507-1522页

作者： Saeid POUYAFAR Mehrdad TARAFDAR HAGH Kazem zare Department of Electrical and Computer Engineering University of TabrizTabrizIran Engineering Faculty Near East UniversityMersin 1099138 NicosiaNorth CyprusTurkey

This paper proposes a new method to allocate the transmission fixed costs among the network participants in a pool-based electricity *** allocation process relies on the circuit laws,utilizes the modified impedance matrix and is performed in two individual steps for the generators and *** determine the partial branch power flows due to the participants,the equal sharing principle is used and validated by the Shapley and Aumann-Shapley values as two preferred game-theoretic *** proposed approach is also applied to determine the generators’contributions into the loads,and a new concept,named circuit-theory-based equivalent bilateral exchange(EBE),is *** the proposed method,fairly stable tariffs are provided for the ***-subsidies are reduced and a fair competition is made by the proposed method due to the counter-flows being alleviated compared with the well-known Z-bus *** results are reported and discussed to validate the proposed cost allocation *** analysis reveals that the method satisfies all conditions desired in a fair and efficient cost allocation ***,the developed technique has been implemented successfully on the 2383-bus Polish power system to emphasize that the method is applicable to very large systems.

关键词： Transmission fixed cost allocation Circuit theory Equal sharing principle Game theory

Numerical Analysis of Complicated Heat and Mass Transfer inside a Wustite Pellet during Reducing to Sponge Iron by H_2 and CO Gaseous Mixture

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2016年第11期23卷 1142-1150页

作者： zare Ghadi ARIYAN Valipour MOHAMMAD SADEGH Biglari MOJTABA Faculty of Mechanical Engineering Semnan University

Heat and mass transfer through a wustite pellet during converting to sponge iron was investigated. Pellet was reduced by a gaseous mixture containing CO and Hz. The grain model was considered to simulate gas solid reac- tion rate. A finite volume method （FVM） was implemented for solving the governing equations. The heat transfer mechanism around the pellet includes radiation and convection and within the pellet, effective heat transfer is consid- ered as a blend of particles conduction and intraparticle radiation. Heat and mass distribution along the radius of pel- let for two cases of reducing gases composed of pure H2 and pure CO was investigated. Local fractional reduction through the pellet was plotted to examine the heat and mass transfer behavior within the pellet and find their rele- vance with reduction degree. Afterwards, the impacts of pertinent parameters including gas ratio, pellet size and po rosity were studied.

关键词： heat transfer mass transfer wustite pellet reduction grain model