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Xinfeng Zhu Yanli Mao Hongpan Liu Haiyan Kang Biao Liu Zhongxian Song Xueping Liu Yifei Guo Huixian Du Qiulin Zhang 《应用有机金属化学》2020,34(2):e5285
FeOx, TiO2, and Fe–Ti–Ox catalysts were synthesized and used in the catalytic hydrolysis of hydrogen cyanide (HCN). Nearly 100% HCN conversion was achieved at 250 °C over the Fe–Ti–Ox catalyst. TiO2 rutile was detected over TiO2, but not over Fe–Ti–Ox, which suggested that the interaction between Fe and Ti species could inhibit the TiO2 phase transition. Furthermore, the interaction between Fe and Ti species over Fe–Ti–Ox could promote the selectivity of NH3 and CO. The mechanism of hydrolysis of HCN over FeOx, TiO2, and Fe–Ti–Ox can be given as follows: HCN + H2O → methanamide → ammonium formate → formic acid → H2O + CO. 相似文献
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《中国化学快报》2023,34(8):108126
Spatial configuration has a significant effect on chemical self-assembly. However, the importance of spatial configuration in supramolecular adhesive materials has been frequently ignored. In this study, the effects of the spatial configuration on cohesion and adhesion were investigated. Owing to the diversities of the chemical structures and assembly patterns, 1,2-disubstituted cyclohexane derivatives were used in this combined experimental and theoretical investigation. The self-sorting assembly of enantiopure isomers improved cohesion but had a negative effect on adhesion. In contrast, racemic mixtures displayed stronger adhesion effects. Moreover, it was proven that the cis-configuration was more favorable for supramolecular adhesion than the trans-counterpart. In addition, the influence of the spatial configuration of 1,2-disubstituted cyclohexane derivatives could be effectively mitigated by hydrogen bond donors or acceptors. The addition of natural acids yielded three-dimensional polymeric networks, in which the spatial configuration was not the decisive factor for supramolecular adhesion. 相似文献
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Inside Back Cover: Fragment‐Based Discovery of a Dual pan‐RET/VEGFR2 Kinase Inhibitor Optimized for Single‐Agent Polypharmacology (Angew. Chem. Int. Ed. 30/2015) 下载免费PDF全文
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Xue-Min Tan Qiao-Mei Lai Zhi-Wei Yang Xiao Long Hai-Lin Zhou Xiao-Lin You Xiao-Jie Jiang Hai-Lei Cui 《Tetrahedron letters》2017,58(2):163-167
A La(OTf)3 catalyzed synthesis of tetrasubstituted pyrroles under microwave irradiation has been developed affording various α-aryl tetrasubstituted pyrroles in acceptable to good yields (36–82% yield) through condensation/alkyne azacyclization/isomerization sequence. Functionalized α-aryl pentasubstituted pyrroles could be prepared from tetrasubstituted pyrroles through easy transformations. 相似文献
7.
On the basis of the mineral banalsit (BaNa2Al4Si4O16) and the addition of small B2O3 concentrations, transparent glasses were prepared. Furthermore, in order to achieve nucleation, LiF and CaF2 were added. Hexacelsian was formed in bulk crystallized glass samples whereas, monocelsian, as well as small quantities of nepheline and banalsite were crystallized from sintered glass powder. The scanning electron micrographs of the sintered samples show high crystallinity and crystals with sizes from nano to micrometers. The SEM micrographs and the EDX microanalyses show that nano size rods of monocelsian surrounded by micrometer-sized hexagonal nepheline, banalsite or residual glassy phase occur. The coefficient of thermal expansion of the samples sintered at 1000 °C was higher (12.93–9.52 × 10−6 K−1) in hexacelsian containing samples than in monocelsian (2.24–7.35 × 10−6 K−1) containing ones. The samples also showed notably different densities of 2.6424 and 2.4718 g/cm3, respectively. 相似文献
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Due to the restriction of computed tomography (CT) scanning environment, the acquired projection data may be incomplete for exact CT reconstruction. Though some convex optimization methods, such as total variation minimization based method, can be used for incomplete data reconstruction, the edge of reconstruction image may be partly distorted for limited-angle CT reconstruction. To promote the quality of reconstruction image for limited-angle CT imaging, in this paper, a nonconvex and nonsmooth optimization model was investigated. To solve the model, a variational proximal alternating linearized minimization (VPALM) method based on proximal mapping in a given metric was proposed. The proposed method can avoid computing the inverse of a huge system matrix thus can be used to deal with the larger-scale inverse problems. What’s more, we show that each bounded sequence generated by VPALM globally converges to a critical point based on the Kurdyka–Lojasiewicz property. Real data experiments are used to demonstrate the viability and effectiveness of VPALM method, and the results show that the proposed method outperforms two classical CT reconstruction methods. 相似文献
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Song Zhongxian Fu Yongmei Ning Ping Liu Hongpan Ren Dong Kang Haiyan Liu Biao Mao Yanli Guo Yifei Zhang Qiulin 《Research on Chemical Intermediates》2019,45(4):2313-2326
Research on Chemical Intermediates - The effect of different pH values (8, 9, 10 and 11) on the catalytic activity over CeSiW catalysts was investigated for the selective catalytic reduction of NO... 相似文献
10.
Ming-Cheng Yang Xue Tang Si-Wei Liu Hui-Qing Deng Jin-Ju Lei Ying-Juan Gao Bo Han Hai-Lei Cui 《Tetrahedron letters》2018,59(2):138-142
A K3PO4 promoted dipolar [3+3] cyclization of dihydroisoquinoline imines and arylacyl bromides has been developed. This process realized the direct synthesis of pyrazino[2,1-a]isoquinoline derivatives in 44–69% yields. A head to tail dimerization was proposed as key step for this procedure. 相似文献