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A fast and efficient method has been developed for generation of sulfonyl nitrene from N,N-dibromo-p-toluenesulfonamide (TsNBr(2)) in the presence of a base without any catalyst. This method was applied to produce aziridines from different kinds of olefins within a short time in high yields. 相似文献
94.
The split feasibility problem is to find a point x? with the property that x?∈ C and Ax?∈ Q, where C and Q are nonempty closed convex subsets of real Hilbert spaces X and Y, respectively, and A is a bounded linear operator from X to Y. The split feasibility problem models inverse problems arising from phase retrieval problems and the intensity-modulated radiation therapy. In this paper, we introduce a new inertial relaxed CQ algorithm for solving the split feasibility problem in real Hilbert spaces and establish weak convergence of the proposed CQ algorithm under certain mild conditions. Our result is a significant improvement of the recent results related to the split feasibility problem.
相似文献95.
Richa Upadhyay Sarvesh Pratap Kashyap Chandra Shekhar Singh Kavindra Nath Tiwari Karuna Singh Major Singh 《Applied biochemistry and biotechnology》2014,174(6):2195-2208
Germplasm storage of Phyllanthus fraternus by using synseed technology has been optimized. Synseeds were prepared from nodal segments taken from in vitro-grown plantlets. An encapsulation matrix of 3 % sodium alginate and 100 mM calcium chloride with polymerization duration up to 15 min was found most suitable for synseed formation. Maximum plantlet conversion (92.5?±?2.5 %) was obtained on a growth regulator-free ½-strength solid Murashige and Skoog (MS) medium. Multiple shoot proliferation was optimum on a ½ MS medium containing 0.5 mg/l 6-benzylaminopurine (BAP). Shoots were subjected to rooting on MS media containing 1 mg/l α-naphthaleneacetic acid (NAA) and acclimatized successfully. Encapsulated nodal segments can be stored for up to 90 days with a survival frequency of 47.33 %. The clonal fidelity of synseed-derived plantlets was also assessed and compared with that of the mother plant using rapid amplified polymorphic DNA and inter-simple sequence repeat analysis. No changes in molecular profiles were observed among the synseed-derived plantlets and mother plant, which confirms the genetic stability of regenerates. This synseed production protocol could be useful for in vitro multiplication, short-term storage, and exchange of germplasm of this important antiviral and hepatoprotective plant. 相似文献
96.
Palakodety Radha Krishna Sunchu Prabhakar Chittela Sravanthi 《Tetrahedron letters》2013,54(7):669-671
Herein we report the first stereoselective total synthesis of nicotlactone A via acid catalyzed acetonide deprotection followed by intramolecular lactonization in one pot as the key step. 相似文献
97.
98.
N. M. Kleinerman V. V. Serikov N. I. Vlasova A. G. Popov A. Kashyap 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(7):822-826
The Mössbauer effect is used to study changes in the structure of Fe50Pd50 alloy in the course of annealing for ordering at T = 450°C from different initial states: cast and quenched from 950°C, then subjected to severe plastic deformation by shear under pressure, and that obtained by fast quenching from the melt. Differences in the kinetics of phase transformations are observed depending on the initial state of the material. 相似文献
99.
Subhash C. Kashyap K. Gopinadhan D.K. Pandya Sujeet Chaudhary 《Journal of magnetism and magnetic materials》2009,321(8):957-962
Room-temperature ferromagnetism has been observed in Co- or Mn-doped SnO2 and Co- and F-co-doped SnO2 thin films. A maximum magnetic moment of 0.80μB/Co ion has been observed for Sn0.90Co0.10O1.925−δF0.075 thin films, whereas in the case of Sn1−xMnxO2−δ it was 0.18μB/Mn ion for x=0.10. The magnetization of both Sn1−xCoxO2−δ and Sn1−xCoxO2−y−δFy thin films depends on the free carrier concentration. An anomalous Hall effect has been observed in the case of Co-doped SnO2 films. However, the same was not observed in the case of Mn-doped SnO2 thin films. Carrier-mediated interaction is convincingly proved to be the cause of ferromagnetism in the case of Co:SnO2. It is, however, proposed that no carrier-mediated interaction exists in the case of Mn:SnO2. Present studies indicate that dopants and hence electronic cloud-lattice interaction plays an important role in inducing ferromagnetism. 相似文献
100.
A theoretical model of a novel planar integrated refractive index sensor based on surface plasmon-polariton (SPP) excitation with a corrugated metal long period grating (LPG) is presented and comprehensively investigated. The main principle of the operation this device is based on co-directional energy transfer by means of a corrugated metal LPG between a p-polarized guided mode propagating in a waveguide layer and the SPP propagating a metal layer separated from the waveguide layer by a buffer. The corrugated LPG is engraved in the metal layer in contact with the sensed medium. The power transmitted through the LPG in the guided mode serves as an input signal for an interrogation unit. This device is free from any moving parts and can be simply integrated into any planar waveguide system. Our sensor simulations are based on the local-normal-mode transfer matrix method and performed in telecom wavelength range. 相似文献