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511.
Anindita Banerjee Kamal Patel Anirban Pathak 《International Journal of Theoretical Physics》2011,50(2):507-510
Recently Yang et al. (Int. J. Theor. Phys. 48:516, 2009) have shown that an unknown qubit can be teleported by using a particular GHZ-like state as quantum channel. However, there are several errors in the calculation which lead to incorrect conclusions. The errors
have been indicated and corrected. It is also noted that their scheme and the independently proposed teleportation scheme
of Zhang et al. (Int. J. Theor. Phys. 48:3331, 2009) uses quantum channel from the same family and any state of that family may be used for teleportation. 相似文献
512.
513.
Bijivemula N. Reddy Peddiahgari Vasu Govardhana Reddy Pogula Sreekanth Reddy S. M. Reddy Sirigi Reddy Sudharsan Reddy Madhavesh Pathak 《合成通讯》2013,43(7):831-837
A new series of 1,2,4-triazolo[4,3-a]-quinoline derivatives were designed and synthesized to meet the structural requirements essential for anticancer activity. N-1-(5-Methylisoxazol-4-yl/4-fluoro-2,3-dihydro-1H-inden-1-yl/aryl)-N’-3-(4,5-dihydro-1-methyl-[1,2,4]triazolo[4,3-a]quinolin-7-yl) urea derivatives were accomplished in good yields by the reaction of 4,5-dihydro-1-methyl-[1,2,4]triazolo[4,3-a]quinolin-7-amine with 3-(3-chloro-5-fluoro-2-methoxyphenyl)-5-methyl-isoxazole-4-carboxylic acid, 4-fluoro-2,3-dihydro-1H-indene-1-carboxylic acid, and various simple aromatic carboxylic acids in the presence of diphenyl phosphoryl azide (DPPA). All the newly synthesized title compounds were characterized by elemental and spectral data. Furthermore, anticancer activity was screened for the title compounds (12a–j) in vitro against human neuroblastoma cell lines (SK N SH) and human colon carcinoma cell lines (COLO 205) by using the MTT cell viability method. A few of them (12a and 12b) possess significant cytotoxicity, and some other compounds 12d-f and 12j displayed moderate cytotoxicity against both cell lines. 相似文献
514.
The field of hypervalent iodine chemistry has been prevalent since 1886. Its journey from obscurity to coming into the limelight has witnessed many effective transformations which have benefited the synthetic community at large. The reactivity of primary amines with hypervalent iodine reagents causes difficulty in synthetic outcome or not feasible due to high exothermicity of amine iodine which is an acid base reaction. This minireview highlights the worthwhile reactivity of hypervalent iodine reagents with aromatic and aliphatic primary amines. Some recent literature has been discussed to make a clear understanding on how such high reactivity of primary amine is controlled by introducing modulation in either substrate or reaction conditions, most of which are carried out under ambient reaction conditions. 相似文献
515.
AbstractIntra-specific chemical variability in the natural population of Gloriosa superba from Eastern Ghats (India) was recorded through validated HPTLC method and in vitro antiarthritic activity of elite chemotypes was evaluated. In total, 36 population(s) of G. superba were mapped and, collected from the phytogeography and densitometric quantification through validated HPTLC-UV method revealed a significant (p?>?0.05) difference in the metabolite content of germplasm(s). Colchicine and gloriosine content varied from 0.005 to 0.275% and 0.003 to 0.119%, maximum was recorded in NBG-34 (Tirupati, Andhra Pradesh) and NBG-70 (Panchgani hill, Maharashtra) respectively. On cluster analysis, six chemotypes were selected for in vitro antiarthritic activity, although activity was not significantly different. The elite chemotype with highest metabolite(s) content did not exhibit the highest biological activity and thus suggests the synergistic action of extract toward the pharmacological activity. The study promotes the use of G. superba in herbal formulation development as an adjuvant therapy in gouty arthritis and will aid in site-specific exploration of elite chemotype(s) with validated pharmacological action to meet out the medicinal and commercial demands. 相似文献
516.
Vijai K. Rai Fooleswar Verma Mansingh Satnami Manorama Singh Ankita Rai 《Tetrahedron letters》2018,59(18):1783-1786
A novel and efficient three-component coupling strategy for stereoselective synthesis of highly substituted tetrahydropyridines (THP) is reported in high yield (83–94%) with excellent diastereoselectivity (95–99%) in favor of anti-isomer. The reaction proceeds via sequential iminium-iminium-enamine mediated formation of three consecutive CC, CC and CN bonds in one-pot through reaction of [E]-α-cyano/nitro unsaturated aldehyde, activated methylene and aldimine/phenyl-N-tosyl-methanimine and opens up a new aspect for the utility of Morita-Baylis-Hillman (MBH) adducts in THP synthesis. 相似文献
517.
J. E. Cunningham M. D. Williams R. N. Pathak W. Jan 《Journal of Crystal Growth》1995,150(1-4):492-496
We find anion incorporation into both GaAs1−yPy on GaAs and InAs1−yPy on InP during gas source molecular beam epitaxy (GSMBE) is not linearly related to the hydride gas fluxes within our reactor. The deviation from an ideal model, i.e., y = ƒP/(ƒP+ƒAs), where As(P) is the flux of AsH3 (PH3), can be as large as a factor of two. GaAsP exhibits the largest degree of nonlinearity and incorporation is found to depend quadratically on the fluxes over a wide range of flux ratio. Significant deviations are also found for InAsP; however, anion incorporation can be modeled with y = ƒP/(ƒP+βƒAs). 相似文献
518.
Ashok Kumar Pathak Rohit Kumar Vivek Kumar Singh Rahul Agrawal Shikha Rai Awadhesh Kumar Rai 《应用光谱学评论》2013,48(1):14-40
Abstract This review assesses the applications of laser-induced breakdown spectroscopy (LIBS) for the analysis of a variety of samples, including biomaterials (teeth, nail, hair, gallstones, and kidney stones, etc.), food materials (fruits and vegetables, milk, salt, nutritional supplements, etc.), medicinal plants, industrial waste, liquid samples, etc. In addition, for the first time the identification of cholesterol and pigment stones was performed on the basis of atomic lines of different elements and molecular bands of C2 molecules present in the LIBS spectra of gallstones. Chemometric techniques such as principal component analysis (PCA) was also applied to LIBS data for rapid identification/classification of different gallstone samples. LIBS analysis of toxic/heavy elements present in vegetables (spinach, tomato) and rice is also presented in this review. It was observed that vegetables grown near industrial areas are rich in several toxic metals like Pb and Cr. The wastewater samples from different industries were also analyzed by recording their spectra using a liquid jet. These results clearly demonstrate the ability of LIBS technique as an instant monitoring device to detect heavy metals present in liquid samples. Finally, this review shows that LIBS is a versatile analytical technique with unlimited applications. 相似文献
519.
In the present work, we report spectroscopic studies of laser-induced plasmas produced by focusing the second harmonic (532 nm) of a Nd:YAG laser onto the laminar flow of a liquid containing chromium. The plasma temperature is determined from the coupled Saha–Boltzmann plot and the electron density is evaluated from the Stark broadening of an ionic line of chromium [Cr(II)] at 267.7 nm. Our results reveal a decrease in plasma temperature with an increase in Cr concentration up to a certain concentration level; after that, it becomes approximately constant, while the electron density increases with an increase in analyte (Cr) concentration in liquid matrix. 相似文献
520.