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991.
Hu Yue Zhi Meiting Zeng Ziqing Lu Wenguan Lai Yinlong Wang Xiaobing 《Research on Chemical Intermediates》2022,48(3):935-948
Research on Chemical Intermediates - In this study, the removal of Cr(VI) using commercial FeS with the partially oxidized surface was investigated under visible light. The results demonstrated... 相似文献
992.
A simple, robust, and accurate HLLC-type Riemann solver for the compressible Euler equations at various Mach numbers is built. To cure shock instability of the HLLC solver at strong shocks, a pressure-control technique, which plays a role in limiting the propagation of erroneous pressure perturbation, is proposed. With an all Mach correction method for the compressible Euler system, the proposed method is further extended to compute flow problems at low Mach numbers. The proposed all Mach HLLC-type scheme has been implemented and used to compute a variety of flow problems ranging from hypersonic compressible to low Mach incompressible flow regimes. Various numerical results demonstrate that the obtained all Mach HLLC-type scheme is both accurate and stable for all speed ranges. 相似文献
993.
994.
Electrochemical Synthesis of Benzazoles from Alcohols and o‐Substituted Anilines with a Catalytic Amount of CoII Salt 下载免费PDF全文
Yin‐Long Lai Prof. Dr. Jian‐Shan Ye Prof. Dr. Jing‐Mei Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(15):5425-5429
An electrochemical synthesis of benzazoles directly from alcohols and o‐substituted anilines has been developed. The reaction conditions have been optimized by varying the composition of the electrolyte and the metal salt used as catalyst. The cyclization proceeds smoothly with a catalytic amount of a cobalt salt under air at room temperature to afford 2‐substituted benzimidazoles, benzothiazoles, and benzoxazoles in good to excellent yields with a wide substrate scope. 相似文献
995.
996.
高碘酸钠-过氧化氢-盐酸黄连素化学发光体系的研究 总被引:5,自引:0,他引:5
1引言 盐酸黄连素是一种用于治疗肠道感染,毒性低、副作用小的天然药物。对盐酸黄连素的测定,化学发光法未见报道。本文发现,过氧化氢存在下,磷酸介质中盐酸黄连素与高碘酸钠反应产生强的化学发光。据此结合流动注射技术建立了在NaIO4-H3PO4-H2O2-盐酸黄连素体系中测定盐酸黄连素的化学发光新方法。方法的检出限为 3.8×10-9g/mL。线性范围是 1.0× 10-8- 7.0 ×10-6g/mL。相对标准偏差为 2.3%( C8= 1. 0 ×10-6g/mL; n=11)。该法与药典方法对照,结果满意。… 相似文献
997.
Glen B. Deacon Prof. Dr. Lai Yoong Goh Prof. Dr. W. Roy Jackson Brian W. Skelton Wei Chen Allan H. White 《无机化学与普通化学杂志》2010,636(8):1478-1483
Monomeric manganese(II) complexes of bulky alkyl/ aryl‐substituted phenoxides, [Mn{C6HnRmO}2(DME)] [ 1 : R = C6H5, n = 3, m = 2 (2,6); 2 : R = Me3C, n = 3, m = 2 (2,6); 3 : R = Me3C, n = 2, m = 3 (2,4,6)] were prepared in yields of 37, 44 and 72 %, respectively, from the reaction of manganese powder, Hg(C6F5)2 and the corresponding phenol in the presence of a little mercury in dimethoxyethane (DME). The compounds were characterized spectroscopically and by magnetic measurements. The single crystal structures of 1 and 3 and also of the mixed phenoxide complex [Mn{(C6H3(C6H5)2‐2,6‐O}{C6H3(Me3C)2‐2,6‐O}(DME)] 4 are reported. 相似文献
998.
Prof. Dr. Long‐Li Lai Shun‐Ju Hsu Hui‐Chu Hsu Sheng‐Wei Wang Dr. Kung‐Lung Cheng Chun‐Jung Chen Tsai‐Hui Wang Prof. Dr. Hsiu‐Fu Hsu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(21):6542-6547
Two series of unconventional triazine‐based dendrimers with C2 symmetry and C3 symmetry were prepared. The newly prepared C3‐symmetrical dendrimers were characterized by 1H and 13C NMR spectroscopy, mass spectrometry, and elemental analysis. Differential scanning calorimetry, polarizing microscopy, and powder XRD showed that the C3‐symmetrical dendrimers display columnar liquid‐crystalline phases during thermal treatment, but the C2‐symmetrical dendrimers were not observed to behave correspondingly. The molecular conformations of C3‐ and C2‐symmetrical dendrimers were obtained by computer simulation with the MM2 model of the CaChe program in the gas phase. The simulation results reasonably explain the different mesogenicities of C3‐ and C2‐symmetric dendrimers. This new strategy should be applicable to other types of unconventional dendrimers with rigid frameworks for displaying columnar liquid‐crystalline behavior. 相似文献
999.
Computer vision systems are employed to determine the major and minor lengths of deformed elliptic grids while determining a sheet metal's workability. The existing method identifies the ellipse using the least squares analysis. It suffers two drawbacks: assumptions in direct conflict with the observed real-world processes and an undesirable property of orientation dependence. For the remedy, this paper presents a new method that, in addition to achieving the desired property of orientation invariance, discards assumptions that conflict with real-world processes. The proposed method is implemented and tested using simulated and real-world data. Results are reported and compared with those obtained by the existing method. 相似文献
1000.
A Princeton Instruments PI-LCX 1300 charge-coupled device (CCD) camera used for X-ray spectrum measurements in laser-plasma experiments is calibrated using three radioactive sources and investigated with the Monte Carlo code Geant4. The exposure level is controlled to make the CCD work in single photon counting mode. A summation algorithm for obtaining accurate X-ray spectra is developed to reconstruct the X-ray spectra, and the results show that the developed algorithm effectively reduces the low-energy tail caused by split pixel events. The obtained CCD energy response shows good linearity. The detection efficiency curves from both Monte Carlo simulations and the manufacturer agree well with the experimental results. This consistency demonstrates that event losses in charge collection processes are negligible when the developed summation algorithm of sDlit Dixel events is emDloved. 相似文献