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31.
o‐Phenylenediamine derivatives readily react with benzoyl chloride derivatives in the presence of MCM‐41 as catalyst to yield 2‐substituted benzimidazoles in very good yields. 相似文献
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Yuanfen Chen Reihaneh Jamshidi Kathryn White Simge Çınar Emma Gallegos Nastaran Hashemi Reza Montazami 《Journal of Polymer Science.Polymer Physics》2016,54(20):2021-2027
Transient Li‐ion batteries based on polymeric constituents are presented, exhibiting a twofold increase in the potential and approximately three orders of magnitude faster transiency rate compared to other transient systems reported in the literature. The battery takes advantage of a close variation of the active materials used in conventional Li‐ion batteries and can achieve and maintain a potential of >2.5 V. All materials are deposited form polymer‐based emulsions and the transiency is achieved through a hybrid approach of redispersion of insoluble, and dissolution of soluble components in approximately 30 min. The presented proof of concept has paramount potentials in military and hardware security applications. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2021–2027 相似文献
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The chemical composition of the essential oils, antioxidant activity (DPPH and beta-carotene/linoleic acid assays) and total phenolic content (Foline-Ciocalteu) of the flowers and leaves of Salvia reuterana were determined. Essential oils extracted from the flowers and leaves by hydrodistillation were analyzed by GC and GC/MS. Forty-four constituents, representing 99.7-99.9% of the oils, were identified. The major components were germacrene D, benzoic acid hexyl ester, bicyclogermacrene, beta-gurjunene and ishwarene, constituting 33.7-31.9% of the oils. The highest radical-scavenging activity (DPPH test) was shown by the methanol extract of the flowers (IC50 = 77.6 microg/mL). In the beta-carotene/linoleic acid assay, the methanol extract of the leaves showed the highest inhibition (40.3%) which was only slightly lower than that shown by BHT (82.9%). The total phenolic contents of the methanol extracts of the flowers and leaves as gallic acid equivalents were 81.4 and 88.3 microg/mg, respectively. The plant also showed good antimicrobial activity against three strains of tested microorganisms. 相似文献
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Saeed Shahrokhian Akbar Mahdavi‐Shakib Masoumeh Ghalkhani Reihaneh‐sadat Saberi 《Electroanalysis》2012,24(2):425-432
The voltammetric behavior of dopamine (DA) and uric acid (UA) on a gold electrode modified with self‐assembled monolayer (SAM) of cysteamine (CA) conjugated with functionalized multiwalled carbon nanotubes (MWCNTs) was investigated. The film modifier of functionalized SAM was characterized by means of scanning electron microscopy (SEM) and also, electrochemical impedance spectroscopy (EIS) using para‐hydroquinone (PHQ) as a redox probe. For the binary mixture of DA and UA, the voltammetric signals of these two compounds can be well separated from each other, allowing simultaneous determination of DA and UA. The effect of various experimental parameters on the voltammetric responses of DA and UA was investigated. The detection limit in differential pulse voltammetric determinations was obtained as 0.02 µM and 0.1 µM for DA and UA, respectively. The prepared modified electrode indicated a stable behavior and the presence of surface COOH groups of the functionalized MWCNT avoided the passivation of the electrode surface during the electrode processes. The proposed method was successfully applied for the determination of DA and UA in urine samples with satisfactory results. The response of the gold electrode modified with MWCNT‐functionalized SAM method toward DA, UA, and ascorbic acid (AA) oxidation was compared with the response of the modified electrode prepared by the direct casting of MWCNT. 相似文献
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Nader Noroozi Pesyan Hamid Rashidnejad Mohammad Ali Esmaeili Elnaz Safari Tuncay Tunç Mostafa Alilou Reihaneh Safavi-Sohi Ertan Şahin 《中国化学会会志》2020,67(9):1679-1695
The reaction of symmetrical (thio)barbituric acids with aldehydes in the presence of 4-methyl morpholine yielded a new form of 4-methyl morpholinium bis-(thio)barbiturate containing charge-separated intermolecular and eight-membered intramolecular H-bonds. X-ray Crystallography, FT-IR, and 1H and 13C-NMR spectroscopy techniques were used for structure characterizations. Some of these compounds showed potent anticancer activities. Cytotoxicity of the synthetic compounds against HeLa and MCF-7 cell lines were performed by MTT assay. In addition, a comparative molecular field analysis was carried out, and the effects of substituents on the biological activities of these compounds were explained. 相似文献
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Let R be a ring and let R 0[x] be the polynomial near-ring over R. We study relations between the set of annihilators in R and the set of annihilators in R 0[x]. 相似文献
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Multi-objective OLSR for proactive routing in MANET with delay,energy, and link lifetime predictions
Zhihao Guo Shahdi Malakooti Shaya Sheikh Camelia Al-Najjar Behnam Malakooti 《Applied Mathematical Modelling》2011,35(3):1413-1426
In this paper, we develop a multi-objective approach for proactive routing in a Mobile Ad Hoc Network (MANET). We consider three routing objectives: minimizing average end-to-end delay, maximizing network energy lifetime, and maximizing packet delivery ratio. Accordingly, we develop three routing metrics: mean queuing delay on each node, energy cost on each node, and link stability on each link. For the proposed multi-objective approach, we develop efficient prediction methods: (a) predicting queuing delay and energy consumption using double exponential smoothing, and (b) predicting residual link lifetime using a heuristic of the distributions of the link lifetimes in MANET. Extensive simulation (by using ns2) is performed for the comparison of this multi-objective OLSR with existing OLSRs. The results show that the multi-objective OLSR is effective in finding optimal routing by tradeoffs among proposed objectives. 相似文献
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Mohammad B. Teimouri Reihaneh Bazhrang 《Monatshefte für Chemie / Chemical Monthly》2009,140(5):513-517
Abstract Protonation of the highly reactive 1:1 intermediate produced in the reaction between alkyl or aryl isocyanides and electron-deficient
acetylenic esters with 3-hydroxy-1H-phenalene-1-one leads to a vinylisonitrilium cation, which undergoes an addition reaction with the conjugate base of the
3-hydroxy-1H-phenalene-1-one to produce biologically interesting dialkyl 10-(alkyl or arylamino)-7-oxo-7H,8H-naphtho[1,8-gh]chromene-8,9-dicarboxylates in moderate to fairly good yields at room temperature.
Graphical abstract
相似文献