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941.
Chang Jun Zou Quan Wu Tang Gui Hong Lan Qiang Tian Tai Yu Wang 《Journal of inclusion phenomena and macrocyclic chemistry》2013,76(1-2):61-68
For the first time, hydroxypropyl-β-cyclodextrin (HP-β-CD) has been brought in to include 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) in order to enhance inhibition efficiency of PBTCA, which leads a new approach to study oil–gas field corrosion inhibition in the process of acid treatment. Based on the host–guest inclusion reaction, the inclusion complex of PBTCA with HP-β-CD has been prepared in the laboratory. UV–Vis absorption spectrum was applied to study the inclusion behavior of PBTCA with HP-β-CD. The results revealed that PBTCA with HP-β-CD can form a 1:1 stoichiometry inclusion complex. The 1:1 inclusion complex synthesized by using lyophilization was further characterized by Fourier transform infrared spectroscopy. Besides, inhibition effect of the inclusion complex on the corrosion inhibition of Q235 carbon steel has been investigated in 0.1 M sulfuric acid (H2SO4) solution using potentiodynamic polarization, electrochemical impedance spectroscopy techniques and scanning electron microscopy (SEM). It was found that the presence of the inclusion complex better achieved the anti-corrosion property in aggressive medium than was the case with alone PBTCA and the highest inhibition efficiency of the inclusion complex over 90 % was obtained, which are suggestive of the active effect of the inclusion complex for improving inhibition efficiency of PBTCA. Meanwhile, the results obtained from SEM further showed that the inclusion complex acts as a more efficient corrosion inhibitor for Q235 carbon steel in H2SO4 medium. 相似文献
942.
Jun Iwabuchi Takashi Kurokawa Zejian Gou Akira Hasegawa 《Journal of carbohydrate chemistry》2013,32(3):605-616
Abstract Benzyl 2,3-anhydro-4-azido-4-deoxy-α-L-ribopyranoside (7), an intermediate for the synthesis of Prumycin was synthesized in 72% yield in seven steps from D-arabinose. Ammonolysis of 7 followed by N-protection with the benzyloxycarbonyl group gave benzyl 4-azido-2-(benzyloxycarbonyl)amino-2,4-dideoxy-α-L-arabinopyranoside (8), which was easily converted to Prumycin. 相似文献
943.
Jian‐Nan Xiang Li‐Hui Jiang Chao‐Yue Chen Zhi‐ying Fu Jun‐Fei Duan Xiao‐Xiao He 《Journal of carbohydrate chemistry》2013,32(7):595-614
New retinoyl sugar derivatives of 13‐cis‐retinoic acid were synthesized in three ways in this paper in order to enhance pharmacal effects, especially antiproliferative activities of 13‐cis‐retinoic acid. Their structures were confirmed by IR, 1H‐NMR, 13C‐NMR, and MS spectra and their antiproliferative activities were determined in vitro using human cancer lines. Results showed that some compounds possessed potential antitumor activities. 相似文献
944.
Jun‐ichi Tamura Akihiro Yamaguchi Junko Tanaka Yuko Nishimura 《Journal of carbohydrate chemistry》2013,32(2):61-82
We have synthesized, for the first time, the partial sequence of the betaglycan composed of the tetraosyl hexapeptide, which was directly usable as a probe for enzymatic glycosyl transfer. Stepwise elongation afforded the corresponding tetraosyl trichloroacetimidate. The common glycosyl dipeptide:[β‐d‐GlcA‐(1→3)‐β‐d‐Gal‐(1→3)‐β‐d‐Gal‐(1→4)‐β‐d‐Xyl‐(1→O)‐Ser‐Gly] was synthesized by glycosylation of the corresponding tetraosyl trichloroacetimidate and Ser‐Gly moiety. The glycosyl dipeptide was coupled with other core peptide parts in solution phase and on a solid support. These glycosyl hexapeptides were then transformed into the desired target compounds. 相似文献
945.
Li Zhang Li Tong Zhang Jing He Zhi Jun Lin Yan Jiang Li Fu Chen 《Journal of Sol-Gel Science and Technology》2013,68(1):150-154
Aluminum nitride (AlN) fibers were prepared from alumina gel fibers and by heat-treatment in ammonia. The influence of silica on the formation of AlN was investigated. It was shown that phase transformation of alumina (γ-Al2O3 to α-Al2O3) and nitridation reaction took place above 1,100 °C for pure alumina fiber. The addition of a small amount of silica (3 wt%) suppressed the formation of α-Al2O3 and preserved the highly reactive metastable alumina, and nitridation rate was enhanced. Fine grain (~20 nm) AlN fibers were obtained for pyrolysis at 1,150–1,250 °C for 3 h in ammonia, and AlN was identified as the sole crystalline phase. 相似文献
946.
Jian Fei Yang Xiu Fang Bian Mei Ling Yuan Yan Wen Bai Yang Liu Jun Peng Fan Xiao Qian Lu Kai Kai Song 《Journal of Sol-Gel Science and Technology》2013,67(2):362-367
The metallic glass/titanium dioxide powders (MG/TiO2) with enhanced photocatalytic oxidation activity were synthesized, which exhibit a higher efficiency in decolorizing methylene blue solutions (MB). Compared with the pure TiO2 and crystalline alloy/TiO2 (CA/TiO2) under the same circumstances, its degradation rate was 60 % and 30 % higher, respectively. Furthermore, compared with the CA/TiO2, the MG/TiO2 photocatalytic rate was three times faster when decolorizing MB. Considering the excellent intrinsic high-performance photocatalytic degradation under visible light irradiation, these novel powders were proven to have potential applications in water purification industry. 相似文献
947.
948.
Dr. Freddi Philippart Marcus Arlt Steve Gotzen Dr. Stefanie‐Joana Tenne Dr. Marco Bocola Dr. Hsui‐Hui Chen Dr. Leilei Zhu Prof. Ulrich Schwaneberg Prof. Jun Okuda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(41):13865-13871
A β‐barrel protein hybrid catalyst was prepared by covalently anchoring a Grubbs–Hoveyda type olefin metathesis catalyst at a single accessible cysteine amino acid in the barrel interior of a variant of β‐barrel transmembrane protein ferric hydroxamate uptake protein component A (FhuA). Activity of this hybrid catalyst type was demonstrated by ring‐opening metathesis polymerization of a 7‐oxanorbornene derivative in aqueous solution. 相似文献
949.
Shuwen Li Zhengping Dong Honglei Yang Shujing Guo Galian Gou Ren Ren Zhejun Zhu Prof. Jun Jin Jiantai Ma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(7):2384-2391
A new catalyst consisting of ionic liquid (IL)‐functionalized carbon nanotubes (CNTs) obtained through 1,3‐dipolar cycloaddition support‐enhanced electrocatalytic Pd nanoparticles (Pd@IL(Cl?)‐CNTs) was successfully fabricated and applied in direct ethanol alkaline fuel cells. The morphology, structure, component and stability of Pd@IL(Cl?)‐CNTs were systematic characterized by transmission electron microscopy (TEM), high‐resolution transmission electron microscopy (HRTEM), Raman spectra, thermogravimetric analysis (TGA) and X‐ray diffraction (XRD). The new catalyst exhibited higher electrocatalytic activity, better tolerance and electrochemical stability than the Pd nanoparticles (NPs) immobilized on CNTs (Pd@CNTs), which was ascribed to the effects of the IL, larger electrochemically active surface area (ECSA), and greater processing performance. Cyclic voltammograms (CVs) at various scan rates illustrated that the oxidation behaviors of ethanol at all electrodes were controlled by diffusion processes. The investigation of the different counteranions demonstrated that the performance of the IL‐CNTs hybrid material was profoundly influenced by the subtly varied structures of the IL moiety. All the results indicated that the Pd@IL(Cl?)‐CNTs catalyst is an efficient anode catalyst, which has potential applications in direct ethanol fuel cells and the strategy of IL functionalization of CNTs could be available to prepare other carbonaceous carrier supports to enhance the dispersivity, stability, and catalytic performance of metal NPs as well. 相似文献
950.
Gadolinium(III)‐Hydroxy Ladders Trapped in Succinate Frameworks with Optimized Magnetocaloric Effect
Yan‐Cong Chen Fu‐Sheng Guo Prof. Dr. Yan‐Zhen Zheng Jun‐Liang Liu Ji‐Dong Leng Róbert Tarasenko Prof. Dr. Martin Orendáč Dr. Jan Prokleška Prof. Dr. Vladimír Sechovský Prof. Dr. Ming‐Liang Tong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(40):13504-13510
Two kinds of inorganic gadolinium(III)‐hydroxy “ladders”, [2×n] and [3×n], were successfully trapped in succinate (suc) coordination polymers, [Gd2(OH)2(suc)2(H2O)]n ? 2n H2O ( 1 ) and [Gd6(OH)8(suc)5(H2O)2]n ? 4n H2O ( 2 ), respectively. Such coordination polymers could be regarded as alternating inorganic–organic hybrid materials with relatively high density. Magnetic and heat capacity studies reveal a large cryogenic magnetocaloric effect (MCE) in both compounds, namely (ΔH=70 kG) 42.8 J kg?1 K?1 for complex 1 and 48.0 J kg?1 K?1 for complex 2 . The effect of the high density is evident, which gives very large volumetric MCEs up to 120 and 144 mJ cm?3 K?1 for complexes 1 and 2 , respectively. 相似文献