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61.
62.
H Kumari SR Kline CL Dennis AV Mossine RL Paul CA Deakyne JL Atwood 《Angewandte Chemie (International ed. in English)》2012,51(37):9263-9266
Metal-containing tubes: The structures of several iron-containing C-methylpyrogallol[4]arene (PgC(1) ) nanoassemblies were studied in both the solid and solution phases. The nanoassemblies have a tubular architecture with the iron as part of the framework (see picture; gray C, red O, turquoise/blue Fe), and magnetic analysis suggests a canted or spiral arrangement of the iron centers. 相似文献
63.
An axiomatic characterization of an information-theoretic quantity associated with a pair of probability distributions having the same number of elements has been given. This quantity, under additional suitable conditions, leads to Kullback's information and Kerridge's inaccuracy concepts. By modifying one of the axioms, the two-parameter generalization of these is obtained. 相似文献
64.
Sunehri L. Chadha Vijay Sharma Sat P. Taneja Deo Raj 《Transition Metal Chemistry》1986,11(10):369-371
Summary The preparation, magnetic moments, i.r., reflectance and57Fe Mössbauer spectra of adducts of tris(2,2,2-trichloroethoxy)iron (III) complexes are reported. An alkoxybridged structure is supported by i.r. spectra.57Fe Mössbauer spectra are explained in terms of two inequivalent sites in highspin iron(III) octahedral symmetry.Abbreviations Pic-O
-picolineN-oxide
- Ur
urea
- DMU
N,N-dimethylurea
- Suc
succinimide
- Diox
dioxan
- Bipy
2,2-bipyridine
- Phen
1,10-phenanthroline 相似文献
65.
Lewis acid mediated one-pot transformation of D-glucal in the presence of nucleophiles leads to the formation of racemic alpha-substituted alpha-hydroxymethyl furfuryl derivatives, versatile synthons for biologically active molecules. Transformations using O-, S-, C-, and N-nucleophiles could be achieved readily under mild and scalable conditions. Indium triflate proved to be the catalyst of choice in terms of conversion and regioselectivity. 相似文献
66.
SbCl3 adsorbed on Al2O3 is found to be an efficient and recyclable catalyst in promoting three-component coupling reactions of aldehydes (aromatic and aliphatic), amines (aryl amines, aliphatic amines and esters of S-α-amino acids) and dialkylphosphites to afford the corresponding α-aminophosphonates in high yields. The ethyl ester of S-phenylalanine was observed to yield the corresponding α-aminophosphonate with S,S-diastereoisomer formed in dominance over the S,R-diastereoisomer. 相似文献
67.
Naresh Padha Vinod Singh E. Subramaniun K. K. Gupta S. C. Taneja K. N. Goswami 《Crystal Research and Technology》1995,30(1):81-86
The crystal structure of methyl-16, nor-5-hydroxy-6,7,15-trioxo dehydroabietate has been determined from three-dimensional X-ray diffraction data. The compound crystallizes in the orthorhombic space group P21212 with unit cell parameters a = 19.226(3) Å, b = 11.075(3) Å, c = 8.375(2) Å, Z = 4, V = 1783.3(7) Å3, d0 = 1.36 gcm−3. The gross structure was determined by direct methods which on refinement yielded a final value of R index as 0.038. Ring A is a chair, ring B an envelope whereas the ring C adopts a strictly planar conformation. The rings A and B are trans fused. The ester group at C4 is cis fused to methyl carbon C15 whereas another methyl carbon C18 and oxo O(15) of the isopropyl group at C13 are rotated to positions 0.107(3) Å and 0.179(2) Å out of the plane of ring C. 相似文献
68.
The structural and chemical properties with non-isothermal crystallization kinetics of PET–ZnO nanocomposites have been reported in this article. ZnO nanoparticles have been synthesized via chemical route with average diameter 19 nm which made confirm by transmission electron microscopy and X-ray diffractometer (XRD) techniques. PET–ZnO nanocomposites have been prepared by solution casting method. The structural and chemical changes occurred in poly (ethylene terephthalate) after inclusion of ZnO nanoparticles have been studied with the help of XRD and Fourier transform infrared spectroscopy, respectively. It was observed from differential scanning calorimeter that ZnO nanoparticles work as nucleating agent for heterogeneous nucleation in PET matrix under non-isothermal crystallization process. The combined Avrami and Ozawa models have been proved adequate to explain non-isothermal crystallization kinetics of PET–ZnO nanocomposites, and also, ZnO nanoparticles have been caused to reduce crystallization activation energy in pristine PET as per the applied Kissinger model. 相似文献
69.
Nitrile oxides undergo addition to allylzinc bromide to generate 5-butenylisoxazolines in good yields. 相似文献
70.