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1.
Christophe Bongars Peter Bougeard Adrian Bury Christopher J. Cooksey Michael D. Johnson Stewart Mitchell Paul A. Owens Famida Rajah 《Journal of organometallic chemistry》1985,289(1):163-171
5-Methylhex-5-enylcobaloxime reacts with carbon tetrachloride and with fluorotrichloromethane at 80–100°C to give substantially pure 1-methyl-1-(β,β,β-trichloroethyl)- and 1-methyl-1-β-fluoro-β,β-dichloroethyl)-cyclopentane. Hex-5-enylco-baloxime also gives trichloroethylcyclopentane from carbon tetrachloride, but the yield is dependent on the concentration of carbon tetrachloride. Similar cyclisation to give trichloroethyl- or fluorodichloroethyltetrahydrofuran is observed in the reactions of hex-3-oxo-5-enylcobaloxime with carbon tetrachloride and fluorotrichloromethane. However, no cyclisation was observed in the reactions of the ester, hex-2-one-3-oxo-5-enylcobaloxime, with carbon tetrachloride. These reactions are believed to take place by attack of a polyhalogenomethyl radical at the terminal unsaturated carbon of the organic ligand, followed either by an intramolecular homolytic displacement in which the carbon radical at position-5 attacks carbon-1 with displacement of cobaloxime(II), or by a halogen atom abstraction. 相似文献
2.
Fathia Rajah Mohsen Graia Tahar Mhiri 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1244-1253
Abstract Sodium copper (II) arsenate Na7Cu4(AsO4)5 has been grown by conventional high-temperature, solid-state methods in molten-salt media. It was characterized by single crystal X-ray diffraction (XRD), thermal analysis (DTA–TGA), scanning electron microscopy (SEM), semiquantitative energy dispersive spectroscopy analysis (EDS), and vibrational spectroscopy. Na7Cu4(AsO4)5 exhibits a three-dimensional framework built up of CuO5, CuO4, and AsO4 polyhedra, with intersecting channels in which the Na+ cations are located. The three-dimensional cohesion of the framework results from Cu–O–As bridges. CuO5 and CuO4 polyhedra are elongated due to the Jahn–Teller effect, whereas AsO4 tetrahedra are almost regular. This new structural model is validated by the charge distribution (CD) analysis. The infrared and Raman spectra confirmed the presence of AsO4 tetrahedra. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional tables and figures.] 相似文献
3.
Usama Fathy Mariam A. Azzam Fathia Mahdy Somia El-Maghraby Rasha M. Allam 《Journal of heterocyclic chemistry》2020,57(5):2108-2120
A new series of tetrahydroquinoline derivatives having pyrazol and hydrazide moieties were synthesized for the purpose of anticancer cell line evaluation. Syntheses of these compounds were firstly achieved by one pot four reactions. The reaction of 3-amino-tetrahydro-1H-pyrazolo [3,4-b]quinolin with aldehydes, indoline-2,3-dione derivatives to give 9a-c , 11a-c , and 13a,b , respectively. In similar manner for biological comparison, the reactions of compound 5 with the same aldehydes and indoline-2,3-dione derivatives to give 19a-c and 20a-c . The newly synthesized compounds were examined in vitro for their cytotoxic activity against HepG-2 and A549 cancer cells. The compounds 11a-c and 20a-c showed promising activity as anticancer agents against HepG-2 and A549 cancer cells. 相似文献
4.
Orin Chein Michael K. Kinyon Andrew Rajah Petr VojtĚChovský 《Results in Mathematics》2003,43(1-2):74-78
Let $\cal F$ be a family of finite loops closed under subloops and factor loops. Then every loop in $\cal F$ has the strong Lagrange property if and only if every simple loop in $\cal F$ has the weak Lagrange property. We exhibit several such families, and indicate how the Lagrange property enters into the problem of existence of finite simple loops. 相似文献
5.
LetLbe a Moufang loop of odd orderpαqα11···qnαnwherepandqiare primes with 3 ≤ p < q1 < ··· < qnand αi ≤ 2. In this paper, we prove thatLis a group ifpandqiare primes with 3 ≤ p < q1 < ··· < qn: (i) α ≤ 3, or (ii) α ≤ 4,p ≥ 5. 相似文献
6.
Jagdish S. Thakur Houbei Dai Gulay K. Serhatkulu Ratna Naik Vaman M. Naik Alex Cao Abhilash Pandya Gregory W. Auner Rajah Rabah Michael D. Klein Carl Freeman 《Journal of Raman spectroscopy : JRS》2007,38(2):127-134
Raman spectroscopy involves the interaction of light with the molecular vibrations and therefore can provide information about molecular structure, tissue composition and changes in its environment. We explored whether Raman spectroscopy can reliably distinguish mammary tumors from normal mammary tissues and other pathological states in mice. We analyzed a large number of Raman spectra from the tumor and normal mammary glands of mice injected with 4T1 tumor cells, which were collected using a high‐resolution (less than 4 cm−1) Raman spectrometer at a fixed (785 nm) laser excitation wavelength and with 60 mW of laser power. The spectra of normal and tumor mammary glands showed consistent differences in the intensity of certain Raman bands and loss of some bands in the tumor spectra. Multivariate statistical methods—principal component analysis (PCA) and discriminant functional analysis (DFA)—were used to separate the data into different groups of mammary tumors, mastitis, lymph nodes contralateral and tumor‐cell‐injected sides, and normal contralateral and tumor‐cell‐injected sides. We demonstrate that this spectroscopic technique has the feasibility of discriminating tumor and mastitis from normal tissues and other pathological states in a short period of time and may detect tumor transformation earlier than the standard histological examination stage. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
7.
S. Mahalakshmi K. Srinivasa Manja S. Nithiyanantham Mohan Rajah 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(11):1938-1939
The magnetic properties nickel ferrites having general chemical formula Ni x Fe(3 ? x)O4 have been studied. The X-ray diffraction measurements confirmed the formation of a cubic spinel structure. The magnetic properties were studied by vibrating sample magnetometer (VSM). It exhibited lower coercivity and higher saturation magnetization due to high crystallinity. The saturation magnetization (M s) and coercivity (H c) for Nd and Gd are different ions since the magnetic moment of Gd3+ is greater than Nd3+. 相似文献
8.
An approach for describing the dynamics of nuclear fission in the framework of generalized quantum mechanics is discussed.
The collective kinetic energy is assumed to be two dimensional, and the reduced mass is allowed to vary with the coordinates.
The generalized calculus of variation is employed for minimizing the action after being properly quantized as required by
Hamilton's principle, employing a curvilinear coordinate system. The corresponding Euler Lagrange equation is identified as
the required generalized equation of motion. The proposed generalized two-dimensional equation of motion is separated into
a vibrational eigenvalue equation and a set of coupled-channel one-dimensional equations which describe the translational
motion, by exploiting the completeness of the vibrational eigenfunctions. Such a system of coupled equations can be decoupled
by replacing the coupling matrix elements by a nonlocal interaction, which can be rendered local after employing the effective
mass approximation. As a consequence this differential equation is provided with an effective mass, an effective potential
barrier, and a differential boundary term which is responsible for restoring the self-adjointness of the kinetic energy differential
operator. 相似文献
9.
A new pulse sequence is proposed to measure cross correlation rates between 1H Curie spin relaxation and 1H-15N or 1H-13C dipole-dipole coupling (%@mt;sys@%Gamma%@sx@%H,HX%@be@%CS,DD%@sxx@%%@mx@% ) in paramagnetic systems. The new sequence has been conceived to obtain quantitative measurements of cross correlation rates in the close proximity to the paramagnetic center, preventing the loss of information due to fast transverse relaxation. The approach was tested on the dicalcium protein calbindin D9k in which Ca2+ has been substituted at site II with Ce3+. At variance with previously reported experiments, all peaks observed in HSQC experiments tailored to paramagnetic signals give quantitative estimates of %@mt;sys@%Gamma%@sx@%H%@ital@%,%@rsf@%HX%@be@%CS%@ital@%,%@rsf@%DD%@sxx@%%@mx@% . This is crucial to refine the immediate proximity of the metal ion. 相似文献
10.