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排序方式: 共有615条查询结果,搜索用时 156 毫秒
1.
The Ramanujan Journal - In this paper, we develop a finite field analogue for one of the Lauricella series, $$F^{(n)}_A$$ . Extending results of Greene, a finite field analogue for the multinomial... 相似文献
2.
A one‐pot, multistep synthesis of acridine‐1,8(2H,5H)‐diones ( 4a–m ) was achieved by three‐component reaction of dimedone ( 1 ) with an aromatic aldehyde ( 2a–m ) and an ammonium acetate ( 3 ) using water as a green solvent without any catalyst and a simple, easily handled, and ultrasonic technique as well as conventional method. 相似文献
3.
Constantine Tsounis Dr. Priyank V. Kumar Dr. Hassan Masood Rutvij Pankaj Kulkarni Prof. Gopalakrishnan Sai Gautam Prof. Christoph R. Müller Prof. Rose Amal Dr. Denis A. Kuznetsov 《Angewandte Chemie (International ed. in English)》2023,62(4):e202210828
MXenes, due to their tailorable chemistry and favourable physical properties, have great promise in electrocatalytic energy conversion reactions. To exploit fully their enormous potential, further advances specific to electrocatalysis revolving around their performance, stability, compositional discovery and synthesis are required. The most recent advances in these aspects are discussed in detail: surface functional and stoichiometric modifications which can improve performance, Pourbaix stability related to their electrocatalytic operating conditions, density functional theory and advances in machine learning for their discovery, and prospects in large scale synthesis and solution processing techniques to produce membrane electrode assemblies and integrated electrodes. This Review provides a perspective that is complemented by new density functional theory calculations which show how these recent advances in MXene material design are paving the way for effective electrocatalysts required for the transition to integrated renewable energy systems. 相似文献
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Chemical oscillation is an interesting nonlinear dynamical phenomenon which arises due to complex stability condition of the steady state of a reaction far away from equilibrium which is usually characterised by a periodic attractor or a limit cycle around an interior stationary point. In this context Lienard equation is specifically used in the study of nonlinear dynamical properties of an open system which can be utilized to obtain the condition of limit cycle. In conjunction with the property of limit cycle oscillation, here we have shown the condition for isochronicity for different chemical oscillators with the help of renormalisation group method with multiple time scale analysis from a Lienard system. When two variable open system of equations are transformed into a Lienard system of equation the condition for limit cycle and isochronicity can be stated in a unified way. For any such nonlinear oscillator we have shown the route of a dynamical transformation of a limit cycle oscillation to a periodic orbit of centre type depending on the parameters of the system. 相似文献
7.
Patil Priyanka T. Warekar Poojali P. Patil Kirti T. Jamale Dattatraya K. Kolekar Govind B. Anbhule Prashant V. 《Research on Chemical Intermediates》2017,43(7):4103-4114
Research on Chemical Intermediates - A convenient and new method has been developed for the synthesis of highly substituted dihydro-2H-dipyrimido[1,2-a,4,5-d]pyrimidine-2,4(3H)-dione derivatives by... 相似文献
8.
Saradhi Kalari Dattatraya A. Babar Uttam B. Karale Vitthal B. Makane Haridas B. Rode 《Tetrahedron letters》2017,58(29):2818-2821
A simple, mild, and ecofriendly protocol for a palladium-catalysed direct arylation of imidazo[1,2-a]pyridines with aryl halides on water is reported. This protocol does not require any ligand and tolerate variety of functional groups on both the coupling partners. The simple base KOH is highly efficient in this transformation. 相似文献
9.
Harshika Agarwal Shweta Yadav Gautam Jaiswar 《Journal of Thermal Analysis and Calorimetry》2017,129(3):1471-1479
The thermal, morphological and optical studies of BaSO4 and MMT (nanoclay) embedded in PVDF were investigated. Nanocomposites samples of PVDF–BaSO4–MMT were prepared by varying the loadings (1–4 mass%) in case of BaSO4 and MMT nanomaterials, respectively. Polyvinylidene fluoride–barium sulfate-montmorillonite (PVDF–BaSO4–MMT) nanocomposites were prepared by solvent-mixing technique. Nanoparticles were synthesized by in situ deposition technique with the help of nonionic polymeric surfactant, and the particle size of nanoparticles was recognized by scanning electron microscopy (SEM) analysis which confirms that the particle has diameter of 80–90 nm. As prepared, nanocomposites films (thickness, 25 μm) were characterized by Fourier transform infrared microscopy (FTIR), SEM and electron diffraction spectroscopy (EDS). FTIR shows that all the chemical constituents were present in the nanocomposites, whereas SEM analysis suggested that the nanofillers dispersed well in polymer matrix and EDS showed the elemental composition of nanocomposite samples. Thermal properties of nanocomposites were studied by using TG/DTA/DTG. TG/DTA studies showed decomposition temperature of pure PVDF is 473.5 °C. The decomposition temperature (T d) of nanocomposites was increased by 93 °C in case of nanocomposites with addition of both BaSO4 and MMT nanomaterials. The difference in the thermal degradation temperature was found to be 1.2% higher in case of addition of BaSO4 nanoparticle as compared to nanoclay. The obtained transparent nanocomposite films were characterized by using UV–Vis spectrophotometer which shows that transparencies of nanocomposites are maintained in visible region, the intensity of absorption band in UV region is increased with the addition of BaSO4 nanoparticles, while in case of addition of nanoclay the UV region does not show drastic changes. Addition of both nanoparticle and nanoclay shows higher absorption in comparison with the individual samples. But further, doubling the amount of nanoparticle and nanoclay shows decrease in UV absorption. Overall, the results of thermal studies show that the incorporation of BaSO4 and MMT could significantly improve the thermal properties of nanocomposites. 相似文献
10.
Pandey Shwetank Shashi Barwa Manjeet Singh Gautam Yogendra Prakash Markandeya Pani Balaram 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):35-43
Journal of Radioanalytical and Nuclear Chemistry - GIS based groundwater uranium and other physico-chemical parameters pH, electrical conductivity, oxidation reduction potential, temperature,... 相似文献