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41.
A. B. Shishmakov Yu. V. Mikushina O. V. Koryakova M. S. Valova S. Yu. Men’shikov L. A. Petrov 《Russian Journal of Applied Chemistry》2011,84(9):1555-1559
Fundamental aspects of the synthesis of 2,3,5-trimethylbenzoquinone by oxidation of 2,3,6-trimethylphenol adsorbed on the
surface of a titanium dioxide xerogel and on TiO2 modified with powdered cellulose with hydrogen peroxide without any organic solvent involved in the process were studied. 相似文献
42.
S. N. Ivanov N. I. Giricheva M. S. Fedorov I. A. Men’shikova T. V. Nurkevich E. G. Tarasova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(4):608-614
An NBO analysis of electronic density distribution is performed for gaseous benzenesulfonic acid and its mono- and trinitro-substituted molecules (B3LYP, MP2, HF /cc-pVTZ). The energy of orbital inter-actions of nitro and sulfonic groups with benzene ring orbitals is calculated for the most stable acid conformers, and the contributions of inductive and resonance effects of substituents are determined. The dependences of these contributions on the positions and number of nitro groups in an aromatic ring and the possibility of intramolecular hydrogen bond formation are revealed. The nitro group in nitrobenzene exhibits a stronger electron-acceptor effect than the sulfonic group in benzenesulfonic acid. Under the influence of the strong electron-acceptor properties of the nitrogroups, the sulfonic group has a donating effect in ortho-nitrosubstituted benzenesulfonic acids. 相似文献
43.
Xue-Hu Men Jin Yang Kun Wang Wei Jiang 《Journal of Dispersion Science and Technology》2013,34(6):780-783
A stable superhydrophobic surface have been fabricated with poly(furfuryl alcohol) (PFA)/polytetrafluoroethylene (PTFE) composite coatings on steel substrates by using a facile method. The observation of field emission scanning electron microscopy revealed that the hierarchical microstructures formed on the surfaces are controlled by varying the curing temperature. This method can be easily operated on substrates of steel, therefore is readily developed to other engineering metal substrates such as aluminum, copper, etc. 相似文献
44.
Wu Men Fenfen Wang Yusheng Zhang Jianhua He Wen Yu Yiliang Li 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(1):89-94
224Ra concentrations in the coastal sea water of western Taiwan Strait in winter were measured using Mn-fiber adsorption—successive emanation scintillation method. 224Ra activities in the seawater of the western Taiwan Strait varied from 0.90 to 16.25 Bq/m3 with an average of 4.60 Bq/m3. The horizontal and vertical distributions of 224Ra were studied. The distributions of 224Ra in the surface water decreased gradually with increasing distance offshore. The apparent horizontal and vertical eddy diffusion coefficients estimated from the one dimensional steady state model of 224Ra were (5.0–55.4) × 106cm2/s and (4.0–51.7) cm2/s, respectively. 相似文献
45.
Demixing and colloidal crystallization in the mixture of charge stabilized colloidal poly(methyl methacrylate) particles and soluble poly(ethylene oxide) were investigated by means of synchrotron small-angle X-ray scattering (SAXS) technique. Phase diagram of the mixture was obtained based on visual inspection and SAXS results. The phase behavior is determined as a function of the concentration of the polymer as well as the volume fraction of the colloidal particles. The system shows a one phase region when the concentration of the polymer is low, whereas a two-phase region is present when the concentration of the polymer is larger than a critical concentration at certain volume fraction of the colloids. Interestingly, a face centered cubic colloidal crystalline structure was formed under certain conditions, which has been rarely observed in experiments of colloid-polymer mixtures with competing interactions. 相似文献
46.
Zhiwei Men Wenhui Fang Shenghan Wang Zhanlong Li Chenglin Sun Xiaojun Wang 《Journal of Raman spectroscopy : JRS》2015,46(4):388-391
The polarized Raman spectra of the upper part of a thin ice Ih film were obtained in the range of 150 cm−1 to 3800 cm−1. The spectra showed clear polarization dependence; several new peaks were also observed. The longitudinaloptic–tranverseoptic (LO–TO) splitting of the mode near 220 cm−1 in the translational vibration region was experimentally confirmed at 133 K. The Fermi resonance between the bending overtone (around 3270 cm−1) and symmetry stretching fundamental (around 3350 cm−1) in the stretching vibration region appeared at nearly the same temperature. Results showed that ice XI (i.e. proton‐ordered phase of ice Ih) slowly formed in the upper part of a thin ice Ih film without KOH as the temperature gradually decreased below 133 K. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
47.
Zhou Yipeng Wang Xiaowei Men Jinfeng Jia Mingchun Liang Chengqiang 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(3):1367-1379
Journal of Radioanalytical and Nuclear Chemistry - In this work, zeolitic imidazolate framework-8 (ZIF-8) with a microporous structure for 60Co and 54Mn adsorption was prepared at room temperature,... 相似文献
48.
Raju Suresh Kumar Abdulrahman I. Almansour Natarajan Arumugam D. Kotresha J. Carlos Menéndez Raju Ranjith Kumar 《Journal of heterocyclic chemistry》2021,58(2):580-588
A three-component, [3 + 2]-cycloaddition/annulation domino protocol is described for the synthesis in excellent yield of a polycyclic cage-like heterocyclic hybrid (PCHH) that comprises various advantaged structural units viz., α,β-unsaturated ketone moiety, 4-pyridinone and pyrroloisoquinoline in a cage-like framework. The antitumor activity of PCHH on human breast (MCF7), colon (HCT116), cervical (JURKAT) and lung (NCI-H460) malignant cell lines inhibited the propagation of all cell lines. This hybrid molecule displayed increased broad-spectrum anticancer activity with higher doses of PCHH. Furthermore, the compound induced 45.21% of early apoptosis and 46.32% of late apoptosis in the Jurkat cancer cell line. Cell cycle analysis showed that this cage-like compound caused cell cycle arrest of Jurkat cells at the S phase and sub G0/G1 phase. Additionally, it led to increased DNA fragmentation and mitochondrial membrane permeabilization through activation of caspase-3 enzyme. Present investigation demonstrates the specific cytotoxic activity of the cage-like compound and the induction of apoptosis through the intrinsic pathway of Jurkat cells. 相似文献
49.
Fully Diastereoselective Synthesis of Polysubstituted,Functionalized Piperidines and Decahydroquinolines Based on Multicomponent Reactions Catalyzed by Cerium(IV) Ammonium Nitrate
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Dr. Padmakar A. Suryavanshi Dr. Vellaisamy Sridharan Dr. Swarupananda Maiti Prof. J. Carlos Menéndez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(28):8791-8799
The cerium(IV) ammonium nitrate (CAN)‐catalyzed, three‐component reaction between primary amines, β‐dicarbonyl compounds, and α,β‐unsaturated aldehydes in ethanol heated to reflux, constitutes a general, one‐pot synthesis of 1,4‐dihydropyridines. Their reduction with sodium triacetoxyborohydride furnished piperidine derivatives bearing up to five substituents with full diastereoselectivity in a hitherto inaccessible stereochemical arrangement. The reaction proceeded with no significant loss of enantiomeric purity under mild reduction conditions that are compatible with several functional groups that are normally sensitive to reduction. Octahydroquinolin‐5‐one derivatives, which were prepared by a modified version of the initial multicomponent reaction, were not suitable substrates for the sodium triacetoxyborohydride mediated reduction, but they were transformed into the corresponding decahydroquinolines, including a precursor of the amphibian alkaloid pumiliotoxin C, by catalytic hydrogenation under a variety of conditions. 相似文献
50.
Wencan Jiang Gongwei Sun Wenbin Cui Shasha Men Miao Jing Danna Pu Sichun Zhang Xiaozhou Yuan Xinrong Zhang Chengbin Wang 《Molecules (Basel, Switzerland)》2020,25(22)
Background: Element-tagged immunoassay coupled with inductively coupled plasma mass spectrometry (ICP-MS) detection has the potential to revolutionize immunoassay analysis for multiplex detection. However, a further study referring to the standard evaluation and clinical sample verification is needed to ensure its reliability for simultaneous analysis in clinical laboratories. Methods: Carcinoembryonic antigen (CEA) and α-fetoprotein (AFP) were chosen for the duplex immunoassay. The performance of the assay was evaluated according to guidelines from the Clinical and Laboratory Standards Institute (CLSI). Moreover, reference intervals (RIs) of CEA and AFP were established. At last, 329 clinical samples were analyzed by the proposed method and results were compared with those obtained with electrochemiluminescent immunoassay (ECLIA) method. Results: The measurement range of the assay was 2–940 ng/mL for CEA and 1.5–1000 ng/mL for AFP, with a detection limit of 0.94 ng/mL and 0.34 ng/mL, respectively. The inter-assay and intra-assay imprecision were all less than 6.58% and 10.62%, respectively. The RI of CEA and AFP was 0–3.84 ng/mL and 0–9.94 ng/mL, respectively. Regarding to clinical sample detection, no significant difference was observed between the proposed duplex assay and the ECLIA method. Conclusions: The ICP-MS-based duplex immunoassay was successfully developed and the analytical performance fully proved clinical applicability. Well, this could be different with other analytes. 相似文献