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81.
Kazi A. Azam Mohitosh Bhowmick Golam Mohammad Golzar Hossain Shariff E. Kabir Kalipada Kundu Khalifa Mohammad Abdul Malik Salina Perven 《Journal of chemical crystallography》2001,31(1):63-68
Treatment of [Ru3(CO)10(-dppm)] (1) with the ditelluride Te2(C6H4OEt-4)2 in refluxing toluene afforded the new aryltellurol bridged complex [Ru2(CO)4(-TeC6H4OEt-4)2 (-dppm)] (2) together with three known complexes [Ru4(CO)8(-CO)(4-Te)2(-dppm)] (3), [Ru2(CO)6{-CH2PPh(C6H4)PPh}] (4), and [Ru2(CO)6{-C6H4PPh(CH2)PPh}] (5). All the four complexes were characterized by spectroscopic methods, including an X-ray structure determination for 5. Complex 5 crystallizes in the monoclinic space group P21/c with a = 13.650(2), b = 9.995(2), c = 18.929(3) Å, = 97.49(2)°, V = 2560.4(8) Å3, and Z = 4. In this complex the two ruthenium atoms are bridged by the phosphino-phosphide ligand C6H4PPh(CH2)PPh which is attached to one Ru by the C6H4 group and a P atom while to the other Ru by both the two P atoms. Both the ruthenium atoms show distorted octahedral geometry. The Ru—Ru bond length is 2.8719(7) Å. 相似文献
82.
Recent developments in the transformation of biobased 5-hydroxymethylfurfural (HMF) into a potential liquid fuel, 2,5-dimethylfuran (DMF), are summarised. This review focuses briefly on the history of HMF conversion to DMF in terms of the feedstock used and emphasises the ideal requirements in terms of the catalytic properties needed in HMF transformation into DMF. The recent state of the art and works on HMF transformation into DMF are discussed in comparison to noble metals and non-noble metals as well as bimetallic catalysts. The effect of the support used and the reaction conditions are also discussed. The recommendations for future work and challenges faced are specified. 相似文献
83.
Akbar Azam Muhammad Arshad Ismat Beg 《Rendiconti del Circolo Matematico di Palermo》2008,57(3):433-441
We prove the existence of points of coincidence and common fixed points of a pair of self-mappings satisfying a generalized
contractive condition in cone metric spaces. Our results generalize several well-known recent and classical results.
相似文献
84.
Zafar Ali Khan Khattak Zia‐ur ‐Rehman Azam Khan Afzal Shah Waqar Zaid Amin Badshah Mohammed Fettouhi Atif Fazal 《Heteroatom Chemistry》2014,25(4):238-244
This article presents a new heteroleptic Zn(II) dithiocarbamate ( 1 ) having molecules linked together via H···H and π···π interactions to form a giant hexanuclear macrocycle. These macrocycles are connected together through S···H interactions to offer a unique two‐dimensional cloth‐like interwoven architecture in the solid state. The redox behavior of the complex deposited on the surface of a glassy carbon electrode was investigated in different pH media. The analyte was found to oxidize and reduce in a pH‐dependent irreversible manner. On the basis of the electrochemical findings, redox mechanistic pathways were proposed. 相似文献
85.
CuO–CeO2 is reported as a highly efficient and green recyclable catalyst,for the multicomponent synthesis of 4H-benzo[b]pyran derivatives.The catalyst was synthesized by a co-precipitation method and characterized by XRD,BET specific surface area,ESEM and EDS analysis.This synthetic method provides several advantages such as simple work-up procedures,minimal amount of waste generated,short reaction time,and high yields of products. 相似文献
86.
Muhammad Sagir Isa M. Tan Muhammad Mushtaq Lukman Ismail Muhammad Nadeem Muhammad Rizwan Azam 《Journal of Dispersion Science and Technology》2014,35(3):463-470
The synthesis of novel CO2 philic surfactant using maleic anhydride and dipropylene tertiary butyl alcohol is reported. The synthesis involved the esterification of maleic anhydride to produce bis(2-(2-(tert-butoxy)propoxy)propyl) maleate and subsequent sulfonation of the esterified product. Para toluene sulfonic acid was employed as catalyst for the esterification reaction. The esterification reaction was optimized for the maximum yield of 98% of bis(2-(2-(tert-butoxy)propoxy)propyl) maleate. The esterification reaction kinetics employing heterogeneous catalyst were also studied. Although this is a bimolecular reaction, a first order reaction kinetics with respect to acid has been observed. The activation energy was found to be 58.71 kJ/mol. The diester was followed by the sulfonation process and a yield of 85% of surfactant was achieved. The synthesized surfactant successfully lowered down the IFT between CO2/brine to 1.93 mN/m. This surfactant has a great potential to be used for CO2-EOR applications. 相似文献
87.
Askari Azam Entezari Amir Arsalan Pordel Mehdi Beigoli Sima Nezafat Yazdi Zeinab Jahani Moghaddam Arya Chamani Jamshidkhan 《Journal of the Iranian Chemical Society》2020,17(1):135-149
Journal of the Iranian Chemical Society - Evaluating the binding interaction between biomacromolecules and various chemical compounds is one of the most biologically researched topics. The present... 相似文献
88.
Masoud Salavati-Niasari Azam Sobhani Sanaz khoshrooz Noshin Mirzanasiri 《Journal of Cluster Science》2014,25(4):937-947
PbS nanoparticles have been successfully synthesized through a simple, rapid microwave route using lead (II) oxalate as precursor, [Pb(O4C2)]. In this study, four different sulfur sources were applied that including sodium thiosulfate (Na2S2O3), thioacetamide (NH2CSCH3), thioglycolic acid (HSCH2CO2H), and l-cysteine (HO2CCH(NH2)CH2SH). The effects of sulfur sources on morphology and size of products in two different solvents, ethylene glycol (EG) and poly EG (PEG 400), were investigated. The products were analyzed by X-ray diffraction analysis, scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray energy dispersive spectroscopy. Photoluminescence was used to study the optical properties of PbS nanoparticles. 相似文献
89.
Behrooz Maleki Saba Hemmati Reza Tayebee Sirous Salemi Yasaman Farokhzad Mehdi Baghayeri Farrokhzad Mohammadi Zonoz Elahe Akbarzadeh Rohollah Moradi Azam Entezari Mohammad Reza Abdi Samaneh Sedigh Ashrafi Fereshteh Taimazi Majid Hashemi 《Helvetica chimica acta》2013,96(11):2147-2151
A convenient synthesis of sulfonamides and sulfonyl azides from thiols is described. In situ preparation of sulfonyl chlorides from thiols was accomplished by oxidation with chloramine‐T (=N‐chlorotosylamide=N‐chloro‐4‐methylbenzenesulfonamide), tetrabutylammonium chloride (Bu4NCl), and H2O. The sulfonyl chlorides were then further allowed to react with excess amine or NaN3 in the same pot. 相似文献
90.
Structural Chemistry - Enterococcus faecium MurF (EfMurF) enzyme catalyzes the addition of d-alanyl-d-alanine to form murein UDP-N-acetylmuramoyl-pentapeptide. This is the last cytoplasmic step of... 相似文献