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1.
Barua  A. Gohain  Boruah  B. R.  Bhattacharyya  S.  Baruah  G. D. 《Pramana》2003,60(1):47-52
Analysis of a part of the meteorite which fell at Dergaon (India) on March 2, 16.40 local time (2001) is presented with the help of FTIR, absorption and atomic spectra. The FTIR spectrum exhibits prominent absorption bands in the region 800–1100 cm−1, originating from the valence vibration of SiO4, a basic component of the silicate lattice.  相似文献   
2.
The first total synthesis of triumfettamide (1) is described. The asymmetric syntheses of two highly functionalized units—α-hydroxylated C17 monounsaturated fatty acid unit (2) and C26 phytosphingosine (3) have been accomplished involving Sharpless asymmetric dihydroxylation, Sharpless kinetic resolution, regioselective epoxide opening, regioselective DIBAL-H reduction of acetal, Wittig olefination as the key steps. Finally N-acylation of phytosphingosine 3 with (2R,6Z)-2-hydroxy-6-heptadecenoic acid 2 followed by DDQ deprotection of PMB, provided target compound 1.  相似文献   
3.
Abstract

The methanolic extract of Cycas revoluta cone (MECR) was analyzed by GC-MS and UHPLC for metabolite profiling and was evaluated for anti-colon cancer property by using in vitro assays like Cell Viability Assay, Colony Formation Assay, ROS Determination, Flowcytometry, DAPI staining assay, Tunel assay. GC-MS and HPLC analysis confirmed the presence of different phytochemicals in the extract of Cycas revoluta cone. In-vitro studies showed MECR extract showed significant anti-colon cancer activity by reducing proliferation and inducing apoptosis in colon cancer cell (HCT-8) line, but no such activity was seen in normal colon cell (CCD-18Co) line. The investigation confirms that MECR may be a promising candidate in colon cancer protection.  相似文献   
4.
Nonlinear Dynamics - We investigated an incompressible viscous liquid film flow over a rotating vertical cylinder of radius R and of infinite length rotating with a uniform angular velocity...  相似文献   
5.
An LC method has been developed for the simultaneous quantitative determination of eugenol, cinnamaldehyde and isoeugenol from dried leaf powder of Cinnamomum tamala Nees & Eberm and stem bark powder of Cinnamomum zeylanicum Breyn. Linear responses for eugenol, cinnamaldehyde and isoeugenol were obtained over the concentration ranges of 0.20–2.50, 5.00–100.00 and 0.10–1.00 μg mL?1, respectively.  相似文献   
6.
A [Ni(CN)4]2−-based two-dimensional Mn(II) coordination polymer {Mn(H2O)2[NiCN]4·4H2O}, in which the coordination layers are stacked on top of each other sandwiching 2D water layer of boat-shaped hexagonal water clusters has been synthesized. The complex exhibits high thermal decomposition temperature and reversible water absorption, which were clearly demonstrated by thermal and PXRD studies on the parent and rehydrated complex after dehydration.  相似文献   
7.
Summary An attempt has been made to represent the interaction energy between two polar molecules by using an effective relative orientation of the pair of the colliding molecules. Calculations made for gaseous ammonia show fairly satisfactory results.  相似文献   
8.
JPC – Journal of Planar Chromatography – Modern TLC - A sensitive and accurate high-performance thin-layer chromatographic method has been developed, validated, and used for...  相似文献   
9.
Proceedings - Mathematical Sciences - We show here that the restriction of photons issuing from the surface of an uncharged sphere with Schwarzschild radius to the radial direction is removed for a...  相似文献   
10.
Radio pulses from extensive air showers (EAS) at 30, 44, and 60 MHz frequencies have been studied, using wide band broad-side arrays of half-wave dipole antenna systems. The experimental results support the theoretical prediction that the field strength of radio emission depends on the shower size. An asymmetry has been noticed in the pulse height distributions of radio pulses detected by North-South and East-West directed arrays. These observations are in agreement with the theory that the charge separation mechanism is predominant in generating radio pulses from EAS and radio emission is polarised in the East-West direction. Experimental data are compared with those of earlier workers.  相似文献   
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