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11.
Zohreh Habibi Peyman Salehi Maryam Yousefi Yahya Hejazi Ahmad Laleh Valiollah Mozaffarian Shiva Masoudi Abdolhossein Rustaiyan 《Chemistry of Natural Compounds》2006,42(6):689-692
The hydrodistilled oils from the aerial parts of Ferula latisecta and Mozaffariania insignis, which is endemic to Iran, were analyzed by GC and GC/MS. (Z)-Ocimenone (32.4%), (E)-ocimenone (20.3%), and cis-pinocarvone (11.4%) were the main components among the 22 constituents characterized in the oil of F. latisecta, representing 87.7% of the total components detected. Twenty-five compounds were identified in the oil of M. insignis, representing 99.0% of the total oil, with octyl acetate (41.1%), β-pinene (30.3%), and α-pinene (23.9%) as the main constituents. The essential oils were examined for their potential antimicrobial activities.
Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 561–563, November–December, 2006. 相似文献
12.
Minoo Jalili Moghaddam Shigeo Hozumi Yoshiaki Inaki Kiichi Takemoto 《Journal of polymer science. Part A, Polymer chemistry》1988,26(12):3297-3308
Polyamides containing thymine photodimer units in the main chain were synthesized, and their photolysis by ultraviolet irradiation below 260 nm were studied in film state. Photodimers of thymine derivatives were obtained by photochemical reaction of the carboxylic acid derivatives of thymine in aqueous solution irradiated above 270 nm. An attempt was made to resolve the isomers of the photodimers, and the two kinds of cis isomers [cis–syn(head to head), and cis–anti(head to tail)] were isolated successfully. The polyamides were prepared by condensation of the photodimers with diamine using an activated ester method. The photodissociation of the thymine photodimer in the polymer main chain caused the breakage of the polymer chains, leading to the production of oligomers and dimer compounds containing thymine bases at the ends of the molecule. The dissociation rate of the polymer did not depend on the kind of the thymine photodimer which was in the main chain of the polymer. 相似文献
13.
Dr. Mahnaz Najafi Dr. Sara Abednatanzi Abbas Yousefi Prof. Mehrorang Ghaedi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(72):17999-18014
Photocatalysis has been known as one of the promising technologies due to its eco-friendly nature. However, the potential application of many photocatalysts is limited owing to their large bandgaps and inefficient use of the solar spectrum. One strategy to overcome this problem is to combine the advantages of heteroatom-containing supports with active metal centers to accurately adjust the structural parameters. Metal nanoparticles (MNPs) and single atom catalysts (SACs) are excellent candidates due to their distinctive coordination environment which enhances photocatalytic activity. Metal-organic frameworks (MOFs), covalent organic frameworks (COFs) and carbon nitride (g-C3N4) have shown great potential as catalyst support for SACs and MNPs. The numerous combinations of organic linkers with various heteroatoms and metal ions provide unique structural characteristics to achieve advanced materials. This review describes the recent advancement of the modified MOFs, COFs and g-C3N4 with SACs and NPs for enhanced photocatalytic applications with emphasis on environmental remediation. 相似文献
14.
Peyman Salehi Mohammad Mehdi Khodaei Amin Rostami 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2235-2243
Alanine/chlorochromic acid/silica gel is a new and selective reagent for the efficient oxidation of sulfides, thiols, oximes, and alcohols. Oxidation of sulfides is solvent dependent. In chloroform at room temperature sulfoxides are formed as the major products, while in carbon tetrachloride or under solvent-free conditions solfones are produced in good-to-excellent yields. 相似文献
15.
This paper presents a method for the construction of a graphene paste electrode (GPE) from reduced graphene oxide (RGO). The GPE was successfully used for the determination of medetomidine. The influence of some experimental variables such as pH, supporting electrolyte, scan rate, and possible interferences were studied. Differential pulse voltammetric (DPV) peak currents of medetomidine increased linearly with its concentration in the range from 0.009 to 2.5 µM. The limit of detection (LOD) and limit of quantitation (LOQ) values for the determination of medetomidine were 2.8 and 9.2 nM, respectively. Also, for the first time, the electroreduction behavior of medetomidine was investigated. 相似文献
16.
Firouz Matloubi Moghaddam Zohreh Mirjafary Marjan Jebeli Javan Sara Motamen Hamid Saeidian 《Tetrahedron letters》2014
A mild and efficient tandem process for the synthesis of new highly substituted 2-pyrones starting from commercially available 2-arylacetic acids has been developed. The synthesis is based on the Knoevenagel condensation of 1,3-cyclohexadiones with various β-formyl-esters, followed by lactonization in the presence of nano ZnO (20 mol %). Moderate to high yields and readily available cheap starting materials are the key features of the present method. 相似文献
17.
18.
In this paper, we classify all capable nilpotent Lie algebras with the derived subalgebra of dimension 2 over an arbitrary field. Moreover, the explicit structure of such Lie algebras of class 3 is given. 相似文献
19.
Niloofar Seydi Behnam Mahdavi Sogand Paydarfard Akram Zangeneh Mohammad Mahdi Zangeneh Fariba Najafi Ali R. Jalalvand Elham Pirabbasi 《应用有机金属化学》2019,33(9)
In recent decades, nanotechnology is growing rapidly owing to its widespread application in science and industry. The aim of the experiment was chemical characterization and evaluation of cytotoxicity, antioxidant, antibacterial, antifungal, and cutaneous wound healing activities of titanium nanoparticles using aqueous extract of Ziziphora clinopodioides Lam leaves (TiNPs@Ziziphora). These nanoparticles were characterized by fourier transformed infrared spectroscopy (FT‐IR), field emission scanning electron microscopy (FE‐SEM), energy dispersive X‐ray spectroscopy (EDS), and UV–visible spectroscopy. The synthesized TiNPs@Ziziphora had great cell viability dose‐dependently (Investigating the effect of the plant on human umbilical vein endothelial cells (HUVECs) cell line) and revealed this method was nontoxic. Then, 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free radical scavenging test was done to assess the antioxidant properties, which indicated similar antioxidant potentials for TiNPs@Ziziphora and butylated hydroxytoluene. Agar diffusion tests were applied to determine the antibacterial and antifungal characteristics. Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC), and Minimum Fungicidal Concentration (MFC) were specified by macro‐broth dilution assay. The data were analyzed by SPSS 21 software (Duncan post‐hoc test). TiNPs@Ziziphora indicated higher antibacterial and antifungal effects than all standard antibiotics (p ≤ 0.01). Also, TiNPs@Ziziphora inhibited the growth of all bacteria at 2‐16 mg/ml concentrations and removed them at 2‐32 mg/ml concentrations (p ≤ 0.01). In case of antifungal properties of TiNPs@Ziziphora, they prevented the growth of all fungi at 2‐8 mg/ml concentrations and destroyed them at 2‐16 mg/ml concentrations (p ≤ 0.01). In vivo experiment, after creating the cutaneous wound, the rats were randomly divided into six groups: untreated control, treatment with Eucerin basal ointment, treatment with 3% tetracycline ointment, treatment with 0.2% TiO2 ointment, treatment with 0.2% Z. clinopodioides ointment, and treatment with 0.2% TiNPs@Ziziphora ointment. These groups were treated for 10 days. For histopathological and biochemical analysis of the healing trend, a 3 × 3 cm section was prepared from all dermal thicknesses at day 10. Use of TiNPs@Ziziphora ointment in the treatment groups substantially reduced (p ≤ 0.01) the wound area, total cells, neutrophil, and lymphocyte and remarkably raised (p ≤ 0.01) the wound contracture, hydroxyl proline, hexosamine, hexuronic acid, fibrocyte, and fibrocytes/fibroblast rate compared to other groups. In conclusion, the results revealed the useful non‐cytotoxic, antioxidant, antibacterial, antifungal, and cutaneous wound healing effects of TiNPs@Ziziphora. 相似文献
20.
B. Najafi 《印度理论与应用数学杂志》2012,43(5):559-567
Using the notion of C-projectively flatness, we give a new characterization of Finsler metrics of constant flag curvature. 相似文献