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991.
Pratibha Nikhil Kumar Atul Kapoor Jaspreet Kaur Rajput Dinesh Singh Varnika 《Electroanalysis》2023,35(4):e202200283
Herein, an effective template assisted calcination procedure has been adopted to synthesize the Sulphur-doped graphitic carbon nitride (SXGCN). Furthermore, the SXGCN/GCE was then utilized for the electrochemical determination of 2,4-Dinitrophenol (2,4-DNP). It has been inferred that among the variously prepared SXGCN (x=0 %, 20 %, 40 %, 60 %, 80 %, and 100 %), S80GCN afforded the excellent electrochemical response for detection of 2,4-DNP. The synthesized SXGCN/GCE (x=80 %) demonstrates with a low detection limit of 0.9083 μM with linear range of 1–90 μM. Furthermore, the practical application of this sensor was successfully proved by detecting spiked 2,4-dinitrophenol in a real gym supplements sample. 相似文献
992.
Damenraj Rajkumar Rainer Künnemeyer Harpreet Kaur Jevon Longdell Andrew McGlone 《Molecules (Basel, Switzerland)》2022,27(2)
Near infrared (NIR) spectroscopy is an important tool for predicting the internal qualities of fruits. Using aquaphotomics, spectral changes between linearly polarized and unpolarized light were assessed on 200 commercially grown yellow-fleshed kiwifruit (Actinidia chinensis var. chinensis ‘Zesy002’). Measurements were performed on different configurations of unpeeled (intact) and peeled (cut) kiwifruit using a commercial handheld NIR instrument. Absorbance after applying standard normal variate (SNV) and second derivative Savitzky–Golay filters produced different spectral features for all configurations. An aquagram depicting all configurations suggests that linearly polarized light activated more free water states and unpolarized light activated more bound water states. At depth (≥1 mm), after several scattering events, all radiation is expected to be fully depolarized and interactions for incident polarized or unpolarized light will be similar, so any observed differences are attributable to the surface layers of the fruit. Aquagrams generated in terms of the fruit soluble solids content (SSC) were similar for all configurations, suggesting the SSC in fruit is not a contributing factor here. 相似文献
993.
Jasmeet Kaur Md. Khalid Anwer Ali Sartaj Bibhu Prasad Panda Abuzer Ali Ameeduzzafar Zafar Vinay Kumar Sadaf Jamal Gilani Chandra Kala Mohamad Taleuzzaman 《Molecules (Basel, Switzerland)》2022,27(4)
The objective of the current research is to develop ZnO-Manjistha extract (ZnO-MJE) nanoparticles (NPs) and to investigate their transdermal delivery as well as antimicrobial and antioxidant activity. The optimized formulation was further evaluated based on different parameters. The ZnO-MJE-NPs were prepared by mixing 10 mM ZnSO4·7H2O and 0.8% w/v NaOH in distilled water. To the above, a solution of 10 mL MJE (10 mg) in 50 mL of zinc sulfate was added. Box–Behnken design (Design-Expert software 12.0.1.0) was used for the optimization of ZnO-MJE-NP formulations. The ZnO-MJE-NPs were evaluated for their physicochemical characterization, in vitro release activity, ex vivo permeation across rat skin, antimicrobial activity using sterilized agar media, and antioxidant activity by the DPPH free radical method. The optimized ZnO-MJE-NP formulation (F13) showed a particle size of 257.1 ± 0.76 nm, PDI value of 0.289 ± 0.003, and entrapment efficiency of 79 ± 0.33%. Drug release kinetic models showed that the formulation followed the Korsmeyer–Peppas model with a drug release of 34.50 ± 2.56 at pH 7.4 in 24 h. In ex vivo studies ZnO-MJE-NPs-opt permeation was 63.26%. The antibacterial activity was found to be enhanced in ZnO-MJE-NPs-opt and antioxidant activity was found to be highest (93.14 ± 4.05%) at 100 µg/mL concentrations. The ZnO-MJE-NPs-opt formulation showed prolonged release of the MJE and intensified permeation. Moreover, the formulation was found to show significantly (p < 0.05) better antimicrobial and antioxidant activity as compared to conventional suspension formulations. 相似文献
994.
Goyal Vikas Singh Arashdeep Singh Jagpreet Singh Tarandip Al-Kheraif Abdulaziz A. Kaur Harpreet Kumar Sanjeev Rawat Mohit 《Journal of Cluster Science》2022,33(6):2831-2831
Journal of Cluster Science - The authors claimed that acknowledgement in published article is not same as provided in revised/accepted paper. 相似文献
995.
This paper extends the fractional programming problem with set-inclusive constraints studied earlier by replacing every coefficient vector in the objective function with a convex set. A dual is formulated, and well-known duality results are established. A numerical example illustrates the dual strategy to obtain the value of the initial problem.The research of the first author was conducted while he was on sabbatical at the Department of Operations Research, Stanford University, Stanford, California. The financial assistance of the International Council for Exchange of Scholars is gratefully acknowledged. The author is grateful to the Department of Operations Research at Stanford for the use of its research facilities. 相似文献
996.
1,4-Dioxane is a flammable liquid and tends to form explosive peroxides. Its formation in glycols (low parts-per-million levels), which are used as dehumidifying agents in refineries, may take place by condensation. 1,4-Dioxane thus formed gets distilled over with benzene in the refinery process. Therefore, it is necessary to identify and determine the levels of 1,4-dioxane in glycols as well as benzene. Gas chromatography (GC) is probably the best technique for this purpose. GC analysis may be carried out using a flame ionization detector. Results show that 1,4-dioxane can be comfortably determined down to 2 ppm in glycols and benzene. 相似文献
997.
Navneet Kaur 《Tetrahedron letters》2004,45(37):6883-6885
N-α-Boc-l-Histidine upon direct τ(N-1) ring alkylation with various alkyl halides in the presence of sodium hydride in DMF or CH3CN easily afforded N-α-Boc-1-alkyl-l-histidines 2a-f. The reaction works equally well in either DMF or CH3CN as solvent, however, CH3CN is preferred due to ease of reaction work-up. 相似文献
998.
B. S. Randhawa P. S. Bassi Sukhraj K. Randhawa Sandeep Kaur 《Journal of Radioanalytical and Nuclear Chemistry》1990,145(4):249-257
Solid state photolysis of alkaline earth tris/malonato/ferrates/III/, i.e., M3[Fe(CH2C2O4)3]2.xH2O /M=Mg, Ca, Sr, Ba/ has been investigated employing Mössbauer, infrared and reflectance spectroscopic techniques. The complexes were irradiated for 400 h using a medium pressure mercury vapour lamp of 250 Watts. Photoreduction led to the formation of M[FeII(CH2C2O4)2(H2O)2]. The extent of photoreduction showed the following order: Ca>Sr>Mg>Ba. The results have been compared with those of analogous alkaline earth tris/oxalato/ferrates/III/. 相似文献
999.
The present investigation deals with the synthesis of seven azomethine derivatives 1–7 of aza heterocyclic amines by carrying out condensation reaction of them with veratraldehyde followed by cyclizing the CHN moiety in synthesized azomethines of 4-amino-1,2,4-triazole and 4-amino antipyrine to yield β lactam derivatives 8–9. The chemical constituents in the synthesized compounds were confirmed by UV, IR, 1H NMR, 13C NMR, and elemental analysis. In vitro antifungal activity of all the synthesized products was done against four pathogenic maize fungal strains i.e. Fusarium verticillioides, Macrophomina phaseolina, Rhizoctonia solani, and Dreschlera maydis. It was found that azomethine derivative having 4-amino-1,2,4-triazole ring was as effective as standard carbendazim 50 WP against R. solani and may be considered as promising antifungal agent; therefore further modifications may be done in its structure to get better drug candidate in future. 相似文献
1000.
Baljeet Kaur Satsangi Seema Kothari Kalyan K. Banerji 《Transition Metal Chemistry》1995,20(3):288-290
Summary The oxidation ofDL-methionine (MT) bybis(2,2-bipyridyl)copper(II) permanganate (BBCP) to the corresponding sulphoxide is first order in BBCP. Michaelis-Menten-type kinetics were observed with respect to MT. The formation constant of the intermediate complex and the rate constant for its decomposition were evaluated. The thermodynamic and activation parameters were also evaluated. The reaction is catalysed by H+ but 2,2-bipyridine does not affect the reaction rate. A mechanism is proposed. 相似文献