Olefin metathesis as a catalytic process constantly gains interest among organic chemists. Over the last decade, it became an efficient tool to accomplish the synthesis of many complex molecules. The development of new well-defined catalysts and continuous examination of novel ligands led to the establishment of metathesis methodology in a group of widespread chemical transformations. Not only ...

an environmentally benign and clean synthesis of aryl-hydrazones by reacting variety of carbonyl compounds with thiosemicarbazide, semicarbazide, aminoguanidine, and phenyl hydrazine has been achieved using aqueous extract of acacia concinna pods as a natural surfactant type catalyst. we found that the aqueous extract of acacia concinna pods could be effectively used for the synthesis of aryl-h...

in this investigation we synthesized nax-nanozeolite by hydrothermal crystallization conditions.these nanoparticles were prepared at different conditions in a temperature controlled shaker. thesynthesized zeolites were characterized by instrumental analysis methods, such as x-raydiffraction (xrd), x-ray fluorescence (xrf), scanning electron microscopy (sem) andtransmission electron microscopy (...

as a new precursor, [tris(2-hydroxyacetophenato) triaqua(iii)], [y(hap)3(h2o)3]; complex was used in thermal decomposition process for the synthesis of rod-like high-temperature ceramic ybco with length of about 320-350 nm and diameters 60–90 nm. the as-synthesized products were characterized by xrd, ft-ir, tem, sem and edx analyses. the results showed that by using fine raw materials, the calc...

fept nanoparticles with thermally stable room-temperature ferromagnetism are investigated. the monodisperse nanoparticles are prepared by chemical synthesis and a salt-matrix annealing technique. structural and magnetic characterizations confirm the phase transition from the disordered face-centered cubic structure. in this paper, 3 nm fept nanoparticles are first synthesized by superhydride re...

The temperature-sensitive mutation in our Escherichia coli strain C1714 appears to be in a ribosomal protein. The mutation maps at the streptomycin locus. Protein synthesis in intact cells stops immediately when the temperature is shifted from 30 to 42 degrees C. Analysis of polyribosome distributions after shift-up suggests that initiation of protein synthesis is defective at the high temperat...

In this research, a single-stage low-temperature hydrothermal synthesis route was successfully developed for preparation of Iron Disulfide. The prepared powder was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). These analyses showed that nanoparticles were well crystallized, pyrite was the main product and the shape of crystals was nanorod. Also, the influences...

In the present work, we have synthesizedgadolinium(III) bromide, GdBr3 from the gadolinium oxide, Gd2O3 by sintering brominating with ammonium bromide, NH4Br. The influence of three main synthesis parameters (contact time, stoichiometry, and temperature) on the reaction yield was studied and optimized. This study showed that the optimum conditions...

Recombination in some intervals of the map of phage lambda is associated with more DNA synthesis than in other intervals. Blockage of DNA synthesis by high temperature in a host temperature-sensitive for DNA synthesis results in the relative reduction of recombinant frequencies in those regions having the larger amounts of recombination-associated synthesis. Reduction of DNA synthesis at normal...

The catalytic highly regio-, diastereo-, and enantioselective synthesis of a small library of spiropyrrolizidineoxindolesvia a four-component 1,3-dipolar cycloaddition reaction of azomethine ylides, derived from isatin, with electron-deficient dipolarophilewas described. The process occurs at room temperature in aqueous ethanol as a green solvent and in the presence of a bidendatebis(imine)–Cu(...