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11.
G. Manasa Arvind K. Bhakta Zineb Mekhalif Ronald J. Mascarenhas 《Electroanalysis》2019,31(7):1363-1372
Increased concern over the risk resorcinol (RS) pose to ecology and humans, led to its position in European Union Category 1 list of endocrine disruptors. Legal measures restricted RS utilization and hence crucial to monitor its levels in the environment. Herein we report development of highly efficient and economically viable electrochemical sensor for quantitative determination of RS based on 77Maghemite/MultiWall Carbon Nanotube (M/MWCNT) modified carbon paste electrode. M/MWCNT was synthesized via strategic IR irradiation for the first time, a promising approach to overcome other complicated chemical routes. Powder X‐ray diffraction (PXRD), Transmission electron microscopy (TEM), Field emission scanning electron microscopy (FESEM) and Energy dispersive X‐ray (EDX) were used for characterization. Using Differential Pulse Voltammetry (DPV), we report the lowest detection limit at 0.02 μM. The potential application of the sensor was accomplished as a result of excellent recoveries made from real samples fortified with RS. Results indicated the proficiency of the sensor reliable for rapid, onsite monitoring of RS water contamination and in biological matrices. 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - The lipophilic character of phytol derivatives has been studied using reverse-phase planar chromatographic procedures.... 相似文献
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Kalkote Uttam Ramrao Choudhary Anil Ramkumar Natu Arvind Anant Ayyangar Nagaraja Ramanuja 《合成通讯》2013,43(10-11):1129-1135
1-Alkylaminoanthraquinones ( 2 a-f) and 1,4-bisalkylaminoanthraquinones ( 4 a-c) were prepared from aminoanthraquinones ( 1,3 ) by alkylation with alkyl sulphate/alkyl halide in presence of powdered sodium hydroxide, potassium carbonate and phase transfer catalyst. 相似文献
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A novel and practical access to symmetrical and unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles directly from aldehydes and acylhydrazides using visible light irradiation under an air atmosphere in the presence of eosin Y as an organophotoredox catalyst at rt is reported. This is the first example of oxidative cyclization of acylhydrazones employing air and visible light as inexpensive, readily available, non-toxic, and sustainable reagents. 相似文献
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In this study, optimum conditions for adsorption of heavy metals such as Cu2+, Cd2+ and Pb2+ onto a low-cost, magnetically modified-alkali conditioned anaerobically digested sludge (MADS) adsorbent were obtained. Response Surface Methodology (RSM) incorporating Central Composite Design (CCD) of experiments was applied to optimize four independent process variables. Statistical analysis was executed by ANOVA and the quadratic model developed had regression coefficients of 0.959, 0.957 and 0.95 for Cu2+, Cd2+ and Pb2+, respectively. The independent variables such as pH, time and initial concentration positively influenced adsorption capacity, qe, whereas the value of qe decreased with an increase in MADS dosage. Model validation experiments for optimization of adsorption process showed comparable results with predicted values. The adsorption capacity of MADS adsorbent at optimum conditions found through RSM analysis was 29.721 mg L?1, 28.551 mg L?1 and 28.601 mg L?1 for Cu2+, Cd2+ and Pb2+ respectively. 相似文献
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Pawar Arvind Gajare Shivanand Patil Audumbar Kurane Rajanikant Rashinkar Gajanan Patil Suresh 《Research on Chemical Intermediates》2021,47(7):2801-2820
Research on Chemical Intermediates - Magnetic separable nanoparticles-decorated N-heterocyclic carbene complex with copper (MNP[1-Methyl benzimidazole]NHC@Cu) has been prepared by covalent grafting... 相似文献
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Bergenia (Saxifragaceae) genus is native to central Asia and encompasses 32 known species. Among these, nine are of pharmacological relevance. In the Indian system of traditional medicine (Ayurveda), “Pashanabheda” (stone breaker) is an elite drug formulation obtained from the rhizomes of B. ligulata. Bergenia species also possess several other biological activities like diuretic, antidiabetic, antitussive, insecticidal, anti-inflammatory, antipyretic, anti-bradykinin, antiviral, antibacterial, antimalarial, hepatoprotective, antiulcer, anticancer, antioxidant, antiobesity, and adaptogenic. This review provides explicit information on the traditional uses, phytochemistry, and pharmacological significance of the genus Bergenia. The extant literature concerned was systematically collected from various databases, weblinks, blogs, books, and theses to select 174 references for detailed analysis. To date, 152 chemical constituents have been identified and characterized from the genus Bergenia that belong to the chemical classes of polyphenols, phenolic-glycosides, lactones, quinones, sterols, tannins, terpenes, and others. B. crassifolia alone possesses 104 bioactive compounds. Meticulous pharmacological and phytochemical studies on Bergenia species and its conservation could yield more reliable compounds and products of pharmacological significance for better healthcare. 相似文献