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报道了一个在聚乙二醇中由卤代芳烃合成不同二芳基硫化物的高效方法.在Cu催化剂作用下,无味、易得、稳定的Na2S2O3· 5H2O盐是有效的硫源. 相似文献
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Khorshed Alam Muhammad Nazeer Abbasi Jinfang Hao Youming Zhang Aiying Li 《Molecules (Basel, Switzerland)》2021,26(10)
Microorganisms are highly regarded as a prominent source of natural products that have significant importance in many fields such as medicine, farming, environmental safety, and material production. Due to this, only tiny amounts of microorganisms can be cultivated under standard laboratory conditions, and the bulk of microorganisms in the ecosystems are still unidentified, which restricts our knowledge of uncultured microbial metabolism. However, they could hypothetically provide a large collection of innovative natural products. Culture-independent metagenomics study has the ability to address core questions in the potential of NP production by cloning and analysis of microbial DNA derived directly from environmental samples. Latest advancements in next generation sequencing and genetic engineering tools for genome assembly have broadened the scope of metagenomics to offer perspectives into the life of uncultured microorganisms. In this review, we cover the methods of metagenomic library construction, and heterologous expression for the exploration and development of the environmental metabolome and focus on the function-based metagenomics, sequencing-based metagenomics, and single-cell metagenomics of uncultured microorganisms. 相似文献
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Dindar Sara Nemati Kharat Ali Safarkoopayeh Barzin Abbasi Alireza 《Transition Metal Chemistry》2021,46(5):403-413
Transition Metal Chemistry - A new half-sandwich ruthenium (II) complex containing β-diketiminate ligand has been synthesized and used for hydroamination of acrylonitrile with aromatic and... 相似文献
116.
S. A. Abbasi 《International journal of environmental analytical chemistry》2013,93(3):173-184
Abstract Zinc (II) was selectively extracted from aqueous solutions of pH 7.8–8.5 into chloroform with N-p-methoxyphenyl-2-furylacrylohydroxamic acid (MFHA). 1-(2-pyridylazo)-2-naphthol (PAN) or 2-[(5-nitro-2-pyridyl)azo]-1-naphthol (NPAN) were added to the extract to form intensely coloured ternary complexes measurable spectrophotometrically at 550 nm (? = 6.03 × 104 1 mol?1 cm?1) and 625 nm (? = 8.15 × 104 mol?1 cm?1) respectively. For atomic absorption spectrometric analysis, methyl isobutyl ketone (MIBK) was used as extracting solvent instead of chloroform and the zinc-MFHA-MIBK extract was aspirated directly into an air-acetylene flame. The absorbance was measured at the 213.9 nm resonance line with a detection limit of 0.05 ppb, which was significantly better than the limit of 1.0 ppb achieved for zinc previously with flame AAS. The method tolerated a large number of anions and cations normally occurring with zinc in environmental samples, and was applied to the trace analysis of zinc in alloys, coal, plant tissues, animal tissues and natural waters. The combinations of MFHA and PAN/NPAN were chosen from eleven hydroxamic acids and nine pyridylazo reagents as detailed in the paper. 相似文献
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Ahmad Abbasi Hajar Roshan-Shekalgourabi Dawood Hassanzadeh-Lelekaami 《Czechoslovak Mathematical Journal》2014,64(2):327-333
Let R be a commutative Noetherian ring with identity and I an ideal of R. It is shown that, if M is a non-zero minimax R-module such that dim Supp H I i (M) ? 1 for all i, then the R-module H I i (M) is I-cominimax for all i. In fact, H I i (M) is I-cofinite for all i ? 1. Also, we prove that for a weakly Laskerian R-module M, if R is local and t is a non-negative integer such that dim Supp H I i (M) ? 2 for all i < t, then Ext R j (R/I,H I i (M)) and Hom R (R/I,H I t (M)) are weakly Laskerian for all i < t and all j ? 0. As a consequence, the set of associated primes of H I i (M) is finite for all i ? 0, whenever dim R/I ? 2 and M is weakly Laskerian. 相似文献
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Jafar Abbasi Shiran Manouchehr Mamaghani Bohari M. Yamin Jalal Albadi Farhad Shirini 《合成通讯》2013,43(13):1520-1532
A convenient, one-pot, three-component regioselective synthesis of novel 2,2′-(1,4-phenylene)-bis-(3-aryl-2-substituted imino-4-aryl-3H-thiazole) derivatives from 1,4-phenylene diisothiocyanate, aryl amines, and various phenacyl bromide, and also the regioselective synthesis of 3-alkyl-2-(aryl imino)-4-cyclopropyl-5-(2′-fluorophenyl)-thiazole derivatives from alkylisothiocyanate, aryl amines, and 2-bromo-2-(2-fluorophenyl)-1-cyclopropylethanone in the presence of poly-4-vinyl pyridine as heterogenous basic catalyst are described. This efficient method produced the products at room temperature with excellent yields (82–96%). The structures of all products were characterized by spectral and elemental analyses. The antimicrobial activity of the synthesized compounds was evaluated against Salmonella enterica, Micrococcus luteus, Bacillus subtilis, and Pseudomonas aeruginosa. 相似文献