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81.
In this work, we used a statistical associating fluid theory to analyze two important thermodynamic regularities for some associating fluids, including water, methanol and ethanol. The studied regularities included: (i) the common bulk modulus point on the isotherms of the reduced bulk modulus versus reduced density, (ii) near linearity of the reduced isothermal bulk modulus as a function of reduced pressure. In this work, we also reported the influence of the molecular size and interaction strength on the bulk modulus point.  相似文献   
82.
This paper presents a fuzzy-neural approach for constraint satisfaction of a generalized job shop scheduling problem (GJSSP) fuzzy processing times. Our study is an extension of recently developed research in a GJSSP where the processing time of operations was constant. Our paper assumes that the processing time of jobs is uncertain. The proposed fuzzy-neural approach can be adaptively adjusted with weights of connections based on sequence resource and uncertain processing time constraints of the GJSSP during its processing. The computational results show that the proposed neural approach is able to find good solutions in reasonable time.  相似文献   
83.
In this research, potassium permanganate in the presence of a catalytic amount of [bmim]Br under solvent free conditions is used as an efficient and chemoselective method for oxidative cleavage of some oximes to corresponding carbonyl compounds. This experiment was carried out in mild conditions without any further oxidation of aldehydes to corresponding acids.  相似文献   
84.
NiAl2O4 spinel nanocrystals were synthesized as mesoporous catalysts and were fully characterized using Fourier‐transform infrared spectroscopy (FT‐IR), X‐ray diffraction patterns (XRD), scanning electron microscopy (SEM), and Energy‐dispersive X‐ray spectroscopy (EDS). These nanocrystals catalyzed the synthesis of 2,3‐dihydroquinazolin‐4(1H)‐one derivatives via a one‐pot, three‐component condensation reaction of aromatic aldehydes, isatoic anhydride, and ammonium acetate or primary aromatic amine under microwave irradiation. By far, the most obvious advantages of the offered process are efficiency and recyclability of the catalyst as well as a significantly shorter reaction time.  相似文献   
85.
A new and efficient methodology for the synthesis of 2‐substituted benzimidazoles is described. In this procedure, CS2 unexpectedly facilitated the cyclization reaction between benzene‐1,2‐diamine and benzenecarbaldehydes in CH2Cl2 at room temperature. The reactions occur under mild conditions require simpler equipment and easier workup procedures.  相似文献   
86.
A new, convenient and high yielding procedure for the preparation of diethyl α-aminophosphonates in water by one-pot reaction of aldehydes, amines, tri/dialkyl phosphites in the presence of a low catalytic amount of [Cu(3,4-tmtppa)](MeSO4)4 (0.16 mol%) as a highly stable and re-usable catalyst is described.  相似文献   
87.
A new family of highly unusual sesquarterpenoids (persicamidines A–E) exhibiting significant antiviral activity was isolated from a newly discovered actinobacterial strain, Kibdelosporangium persicum sp. nov., collected from a hot desert in Iran. Extensive NMR analysis unraveled a hexacyclic terpenoid molecule with a modified sugar moiety on one side and a highly unusual isourea moiety fused to the terpenoid structure. The structures of the five analogues differed only in the aminoalkyl side chain attached to the isourea moiety. Persicamidines A–E showed potent activity against hCoV-229E and SARS-CoV-2 viruses in the nanomolar range together with very good selectivity indices, making persicamidines promising as starting points for drug development.  相似文献   
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