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91.
Filippo Manna 《Meccanica》1967,2(3):175-177
Summary The group of profiles is found out according to which, in theory, the meridian of a shell of revolution, submitted to the action of a uniform internal pressure, should be shaped so that the hoop force be equal to zero in any point of the shell.
The present note has been performed in the frame of activity of C.N.R. (Pressure Vessels Design Research Group). 相似文献
Sommario Viene individuata la schiera dei profili secondo cui occorrerebbe teoricamente sagomare il meridiano d'un involucro di rotazione che, assoggettato a pressione interna uniforme, risulti perfettamente scarico nei confronti della tensione normale al meridiano stesso.
The present note has been performed in the frame of activity of C.N.R. (Pressure Vessels Design Research Group). 相似文献
92.
Shyamaprosad Goswami Avijit Kumar Das Krishnendu Aich Abhishek Manna Hoong-Kun Fun Ching Kheng Quah 《Supramolecular chemistry》2013,25(2):94-104
A simple novel receptor, designed to have a combination of both oxygen and nitrogen-binding sites for metal ion and hydrogen bond donor sites for anion, was synthesised. The receptor has been explored for the selective detection of cation Al3+ over the other interfering metal ions and anion AcO? against a range of physiologically relevant anions in the fluorescence spectroscopy. The receptor shows a different response to aluminium and acetate in the emission spectra. The binding isotherm and detection limit demonstrate that the receptor is an excellent fluorometric probe for Al3+ and AcO? . 相似文献
93.
A synthetic approach toward xanthone and fluorenone derivatives through ruthenium catalyzed intra-molecular C–H bond functionalization using an external oxidant has been developed. In the presence of [RuCl2(p-cymene)2]2, a variety of substituted ortho-aryloxy/aryl benzaldehydes underwent cross dehydrogenative coupling to afford the corresponding analogs in moderate to good yields. 相似文献
94.
Suresh Kumar Mondal Susanta Kumar Manna Arabinda Mandal Shubhankar Samanta Jayanta K. Ray 《Tetrahedron letters》2014
A convenient and efficient procedure has been developed for the synthesis of a new ring system, pyrrolo[1,2-b]pyrazolone, via two-component coupling reaction followed by base mediated intramolecular cyclization. Single-pot synthesis replacing the two step process has also been successfully carried out. A series of polycyclic pyrrolo[1,2-b]pyrazolone derivatives have been obtained by employing the procedure along with some fused pyrrol-1-ylamine system. The products were formed very rapidly in catalyst free condition in a good yield (up to 75%) and also it had tolerance to a wide scope of substrates. 相似文献
95.
Unique Fluorogenic Ratiometric Fluorescent Chemodosimeter for Rapid Sensing of CN− in Water
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Dr. Ajit Kumar Mahapatra Kalipada Maiti Saikat Kumar Manna Rajkishor Maji Chitrangada Das Mukhopadhyay Bholanath Pakhira Prof. Sabyasachi Sarkar 《化学:亚洲杂志》2014,9(12):3623-3632
A new benzimidazole‐spiropyran conjugate chemosensor molecule ( BISP ) has been synthesized and characterized by 1H NMR spectroscopy, mass spectrometry (ESI‐MS), and elemental analysis. The two isomeric forms ( BISP ? BIMC ) were shown to be highly selective and sensitive to CN? among the ten anions studied in aqueous HEPES buffer, as shown by fluorescence and absorption spectroscopy and even by visual color changes, with a detection limit of 1.7 μM for BIMC . The reaction of CN? with BIMC was monitored by 1H NMR spectroscopy, high‐resolution mass spectrometry (HRMS), UV/Vis measurements, and fluorescence spectroscopy in HEPES buffer of pH 7.4. TDDFT calculations were performed in order to correlate the electronic properties of the chemosensor with its cyanide complex. Further, titration against thiophilic metal ions like Au3+, Cu2+, Ag+, and Hg2+ with [ BIMC‐CN ] in situ showed that it acts as a secondary recognition ensemble toward Au3+ and Cu2+ by switch‐on fluorescence. In addition, a reversible logic‐gate property of BIMC has been demonstrated through a feedback loop in the presence of CN? and Au3+ ions, respectively. Furthermore, the use of BIMC to detect CN? in live cells by fluorescence imaging has also been demonstrated. Notably, test strips based on BIMC were fabricated, which could serve as convenient and efficient CN? test kits. 相似文献
96.
Zdzisław Brzeźniak Utpal Manna Akash Ashirbad Panda 《Journal of Differential Equations》2019,266(10):6204-6283
In this work we consider a stochastic evolution equation which describes the system governing the nematic liquid crystals driven by a pure jump noise in the Marcus canonical form. The existence of a martingale solution is proved for both 2D and 3D cases. The construction of the solution relies on a modified Faedo–Galerkin method based on the Littlewood–Paley-decomposition, compactness method and the Jakubowski version of the Skorokhod representation theorem for non-metric spaces. We prove that in the 2-D case the martingale solution is pathwise unique and hence deduce the existence of a strong solution. 相似文献
97.
Nanocrystalline Mn1−xZnxFe2O4 (0.2?x?0.9) was prepared by mechanical alloying of the concerned oxide precursors and subsequent annealing in air and Ar atmosphere, respectively. Milling and annealing in air produces Zn-ferrites (ZnFe2O4) instead of Mn–Zn ferrites as MnO converts to higher oxides at higher oxygen partial pressure and fails to dissolve in the spinel phase. This is confirmed by careful quantitative X-ray diffraction analysis using Rietvelt profile matching and also by the non-saturating paramagnetic nature of the magnetization response with very low saturation level of these spinels milled and annealed in air. On the other hand, single-phase Mn–Zn ferrite results from the identical precursor oxide blend when milling and annealing are carried out under controlled (Ar) atmosphere. The average grain size of the as-milled and annealed powders, measured by Rietvelt refinement, varies between 6–8 and 14–18 nm, respectively. Further investigations performed with Mn0.6Zn0.4Fe2O4 reveal that a careful selection of annealing parameters may lead to an early superparamagnetic relaxation. Therefore, the blocking temperature can be significantly reduced through proper heat treatment schedule to ensure superparamagnetism and negligible hysteresis at low temperature. 相似文献
98.
The paper presents the covariation of seasonal intensity values of 5893 Å and 5577 Å lines of night airglow emissions and seasonal values of ozone concentration at Calcutta (Kolkata) with relative sunspot number, solar ultraviolet flux and solar 10.7 cm wavelength radio flux during the years 1984, 1985 and 1987. Various statistical parameters including coefficients of correlation between the atmospheric and solar quantities are computed. Possible explanation for the covariation of the quantities is provided invoking the excitation mechanisms and chemical reactions underlying them. 相似文献
99.
100.
Prof. Guowei Li Dr. Qun Yang Prof. Kaustuv Manna Dr. Yudi Zhang Dr. Patrick Merz Chandra Shekhar Yang Zhang Dr. Hua Lv Dr. Anastasios Markou Dr. Yan Sun Prof. Claudia Felser 《Angewandte Chemie (International ed. in English)》2023,62(27):e202303296
The study of heterogeneous reactions for enantiomeric processes based on inorganic crystals has been resurgent in recent years. However, the question remains how homochirality develops in nature and chemical reactions. Here, the successful growth of B20 group PdGa single crystals with different chiral lattices enabled us to achieve enantioselective recognition of 3,4-dihydroxyphenylalanine (DOPA) based on a new mechanism, namely orbital angular momentum (OAM) polarization. The orbital textures of PdGa crystals indicate large OAM polarization near the Fermi level and carrying opposite signs. A positive or negative magnetization in the [111] direction is expected depending on the chiral lattice of PdGa crystals. Due to this, the adsorption energies of PdGa crystals and DOPA molecules differ depending on how well the O-2p orbital of DOPA pairs with the Pd-4d orbital of PdGa. The results provide one possible explanation for how chirality arises in nature by providing an enantioselective route with pure inorganic crystals. 相似文献