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1.
Subhi A. Al-Jibori Rawaa A. Q. Al-Nassiry Ghassan H. H. Al-Jibori Kurt Merzweiler Christoph Wagner Harry Schmidt Sucharita Basak-Modi Graeme Hogarth 《Transition Metal Chemistry》2014,39(7):735-740
Reaction of Na2[PdCl4] with two equivalents of amino- or acetylamino-pyridines (LH) affords trans-[PdCl2-(LH)2] {LH = 2-amino-3-methylpyridine (2-ampyH), 3-aminopyridine (3-apyH), 2-acetylamino-3-methylpyridine (2-acmpyH), 3-acetylamino-pyridine (3-acpyH)}. An X-ray crystal structure of trans-[PdCl2(2-ampyH)2] shows that the 2-ampy-H ligands are coordinated in a monodentate fashion via the nitrogen atoms of the pyridine rings. Treatment of trans-[PdCl2(2-acmpyH)2] with NEt3 affords the cyclometalated complex, trans-[Pd(κ2-2-acmpy)2], the X-ray structure of which shows that the 2-acmpy ligand is coordinated to palladium in a bidentate fashion via the nitrogen atom of the pyridine ring and oxygen. Reaction of trans-[PdCl2(LH)2] with two equivalents of sodium saccharinate affords the bis(saccharinate) complexes, trans-[Pd(sac)2(LH)2], in which the saccharinate anions are coordinated via the amide nitrogen atom. 相似文献
2.
Dattatray J. Late Mahendra A. More Sucharita Sinha K. Dasgupta Pankaj Misra B. N. Singh Lalit M. Kukreja Sudha V. Bhoraskar Dilip S. Joag 《Applied Physics A: Materials Science & Processing》2011,104(2):677-685
The paper deals with the comparative study of nanocrystalline Lanthanum hexaboride (LaB6) thin films grown on various substrates by Pulsed laser deposition and Arc plasma method. Field emission studies were carried
out on LaB6 films deposited on various substrates show metallic behavior of the emitters. The high value of field enhancement factors,
indicating that the electron emission from LaB6 nanoscale protrusions deposited on emitter surface. The post field emission surface morphology of the emitters showed no
significant erosion of the films during continuous operation. The observed behavior indicates that it is linked with the growth
of LaB6 films on substrate crystal structure. The LaB6 nanocrystallites/nanowires films were synthesized using arc plasma method shows good emission current stability. The LaB6 micro/nanocrystallites were also obtained by picosecond laser irradiation which gives high enhancement β factor, and good emission current stability along with high current density. The results reveal that nanocrystalline LaB6 films, exhibit high resistance to ion bombardment and excellent structural stability and are more promising emitters for
practical applications in field emission based new generation devices. 相似文献
3.
Sucharita Banerjee Gregory M. Ferrence Shawn R. Hitchcock 《Tetrahedron: Asymmetry》2010,21(7):837-845
(1S,2S)-Pseudoephedrine and (1S,2S)-pseudonorephedrine have been converted to their corresponding hydrazines and condensed with either o-salicylaldehyde or 2-hydroxy-1-naphthaldehyde to afford a series of β-hydroxysalicylhydrazones that have been employed in the asymmetric addition of diethylzinc to 2-naphthaldehyde in up to 56% ee. In addition to this, the Ephedra hydrazines were also condensed with the o-hydroxyacetophenone derivative to form related hydrazones. The use of these corresponding hydrazones in the asymmetric addition reaction with the diethylzinc did not yield improved enantioselectivities. Finally, Enders’ hydrazine was used as a chiral scaffold for the synthesis of β-methoxysalicylhydrazones. These compounds were employed in the asymmetric addition of diethylzinc to a variety of aromatic aldehydes with enantiomeric excesses as high as 68% ee. 相似文献
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Complexes of the general formula [ReIII(L)Cl(PPh3)2] have been synthesised by reacting H2L and [ReOCl3(PPh3)2] in ethanol. Here H2L represents imines of α-amino acids (glycine, l-alanine, l-valine, l-phenylalanine) derived from salicylaldehyde and naphthaldehyde. The crystal structure of one complex has been determined. The complexes are mononuclear, paramagnetic and display paramagnetic 1H NMR in CDCl3 solution. Their spectral and redox properties are scrutinised. 相似文献
6.
We compare two estimates of the cumulant generating function of a stationary linear process. The first estimate is based on
the empirical moment generating function. The second estimate uses the linear representation of the process and the empirical
moment generating function of the innovations. Asymptotic expressions for the mean square errors are derived under short-
and long-range dependence. For long-memory processes, the estimate based on the linear representation turns out to have a
better rate of convergence. Thus, exploiting the linear structure of the process leads to an infinite gain in asymptotic efficiency. 相似文献
7.
Abstract Consider two independent random variables x and y with means and standard deviations μ x ,μ y ,σ x , and σ y , respectively. Let F x (t) = P[(x - μ, x )/σ x ≤ t] and F y (t) = P[(y - μ y )/σ y ≤ t]. In this article we address the problem of testing the null hypothesis H 0 : F x ≡ F y , against the alternative H 1 : F x ≡ F y . A graphical tool called T 3 plot for checking normality of independently and identically distributed univariate data was proposed in an earlier article by Ghosh. In the present article we develop a two-sample T 3 plot where the basic statistic is the normalized difference between the T 3 functions for the two samples. Significant departure of this difference function from the horizontal zero line is indicative of evidence against the null hypothesis. In contrast to the one-sample problem, the common distribution function under the null hypothesis is not specified in the two-sample case. Bootstrap is used to construct the acceptance region under H 0, for the two-sample T 3 plot. 相似文献
8.
Vanadium(V) oxidation of D ‐glucose shows first‐order dependence on D ‐glucose, vanadium(V), H+, and HSO. These observations remain unaltered in the presence of externally added surfactants. The effect of the cationic surfactant (i.e., N‐cetylpyridinium chloride [CPC]), anionic surfactant (i.e., sodium dodecyl sulfate [SDS]), and neutral surfactant (i.e., Trion X‐100 [TX‐100]) has been studied. CPC inhibits the reactions, whereas SDS and TX‐100 accelerate the reaction to different extents. Observed effects have been explained by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 282–286, 2008 相似文献
9.
Prof. Dr. Jean Christophe Tremblay Ambre Blanc Dr. Pascal Krause Sucharita Giri Prof. Gopal Dixit 《Chemphyschem》2023,24(2):e202200463
The present work focuses on probing ultrafast charge migration after symmetry-breaking excitation using ultrashort laser pulses. LiCN is chosen as prototypical system because it can be oriented in the laboratory frame and it possesses optically-accessible charge transfer states at low energies. The charge migration is simulated within the hybrid time-dependent density functional theory/configuration interaction framework. Time-resolved electronic current densities and simulated time-resolved x-ray diffraction signals are used to unravel the mechanism of charge migration. Our simulations demonstrate that specific choices of laser polarization lead to a control over the symmetry of the induced charge migration. Moreover, time-resolved x-ray diffraction signals are shown to encode transient symmetry reduction at intermediate times. 相似文献
10.
Sucharita Sen Lalitagauri Ray Parimal Chattopadhyay 《Applied biochemistry and biotechnology》2012,167(7):1938-1953
A fungal strain isolated from rotten banana and identified as Aspergillus alliaceus was found capable of producing thermostable extracellular ??-galactosidase enzyme. Optimum cultural conditions for ??-galactosidase production by A. alliaceus were as follows: pH?4.5; temperature, 30?°C; inoculum age, 25?h; and fermentation time, 144?h. Optimum temperature, time, and pH for enzyme substrate reaction were found to be 45?°C, 20?min, and 7.2, respectively, for crude and partially purified enzyme. For immobilized enzyme?Csubstrate reaction, these three variable, temperature, time, and pH were optimized at 50?°C, 40?min, and 7.2, respectively. Glucose was found to inhibit the enzyme activity. The K m values of partially purified and immobilized enzymes were 170 and 210?mM, respectively. Immobilized enzyme retained 43?% of the ??-galactosidase activity of partially purified enzyme. There was no significant loss of activity on storage of immobilized beads at 4?°C for 28?days. Immobilized enzyme retained 90?% of the initial activity after being used four times. 相似文献