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51.
In this paper we report some explicit evolutionary PDEs of the Drinfeld-Sokolov hierarchy of type E(1)6,and show how the unknown functions in these PDEs are rel... 相似文献
52.
Yue Liu Congmin Wang Rong Guo Juexiu Li Quan Zhao Weiqiang Wang Fei Qi Haifang Liu Yang Li Huifan Zheng 《Molecules (Basel, Switzerland)》2022,27(15)
Iron–manganese silicate (IMS) was synthesized by chemical coprecipitation and used as a catalyst for ozonating acrylic acid (AA) in semicontinuous flow mode. The Fe-O-Mn bond, Fe-Si, and Mn-Si binary oxide were formed in IMS on the basis of the results of XRD, FTIR, and XPS analysis. The removal efficiency of AA was highest in the IMS catalytic ozonation processes (98.9% in 15 min) compared with ozonation alone (62.7%), iron silicate (IS) catalytic ozonation (95.6%), and manganese silicate catalytic ozonation (94.8%). Meanwhile, the removal efficiencies of total organic carbon (TOC) were also improved in the IMS catalytic ozonation processes. The IMS showed high stability and ozone utilization. Additionally, H2O2 was formed in the process of IMS catalytic ozonation. Electron paramagnetic resonance (EPR) analysis and radical scavenger experiments confirmed that hydroxyl radicals (•OH) were the dominant oxidants. Cl−, HCO3−, PO43−, Ca2+, and Mg2+ in aqueous solution could adversely affect AA degradation. In the IMS catalytic ozonation of AA, the surface hydroxyl groups and Lewis acid sites played an important role. 相似文献
53.
Guo Shihang Feng Yi Ding Weiqiang Li Xiaodan Yang Lvye Yao Jianfeng 《Journal of Solid State Electrochemistry》2019,23(1):1-7
Journal of Solid State Electrochemistry - The morphology of Co-based zeolitic imidazolate framework is affected by the molar ratio of 2-methylimidazole and Co2+ used during the synthesis. In this... 相似文献
54.
本文报道在手性表面活性剂N,N-二甲基-N-十二烷基麻黄素溴化铵(Ia),N,N-二甲基-N-十六烷基麻黄素溴化铵(Ib)及N,N-二甲基-N-十六烷基溴化薄荷铵(Ⅱ)形成的手性胶束水溶液中,α-二酮被TiCl_2还原为光学活性的α-羟基酮,对映体过量最高可达30%. 相似文献
55.
Weiqiang Wang 《Communications in Mathematical Physics》2003,234(1):101-127
For a space X acted on by a finite group Γ, the product space X
n
affords a natural action of the wreath product Γ
n
=Γ
n
⋊S
n
. The direct sum of equivariant K-groups were shown earlier by the author to carry several interesting algebraic structures. In this paper we study the K-groups of Γ
n
-equivariant Clifford supermodules on X
n
. We show that is a Hopf algebra and it is isomorphic to the Fock space of a twisted Heisenberg algebra. Twisted vertex operators make a
natural appearance. The algebraic structures on ℱ−
Γ(X), when Γ is trivial and X is a point, specialize to those on a ring of symmetric functions with the Schur Q-functions as a linear basis. As a by-product, we present a novel construction of K-theory operations using the spin representations of the hyperoctahedral groups.
Received: 3 February 2001 / Accepted: 17 August 2002 Published online: 10 January 2003 相似文献
56.
Han Xiaoqian Liu Yueqi Zhang Yuhua Zhang Weiqiang Li Yongmin Chen Liren 《Chromatographia》2002,56(5-6):319-322
Summary Amylose tris(phenylcarbamate) (ATPC) coated on a small particle silica gel was prepared. This ATPC chiral stationary phase
(ATPC-CSP) was found to be useful for the enantiomeric separation of some novel chiral tetrahedrane-type clusters. Moreover,
the influence of mobile phase modifier and of the structure of chiral tetrahedrane-type clusters on the chiral separation
and retention were investigated. The results suggest that not only the structure and concentration of alcohol in mobile phase,
but also the subtle structural differences in racemates can have a pronounced effect on enantiomeric separation and retention. 相似文献
57.
为了探讨胸腺五肽对重型脑损害病人T淋巴细胞亚群的影响,从湛江市第二人民医院1999年1月至2005年1月住院的重型脑损害病人90例中,随机分为胸腺五肽治疗组和对照组,观察了两组T淋巴细胞亚群的变化,并评价其临床疗效。结果表明,对照组的n(CD4 )/n(CD8 )比值显著低于治疗组(P<0.01);治疗组的死亡率为5%,显著低于常规治疗组(P<0.01)。结果表明,胸腺五肽可显著改善重型脑损害病人的免疫力,降低死亡率,有推广应用价值。 相似文献
58.
郭伟强 《分析测试技术与仪器》1996,2(4):9-19
对毛细管电泳的光学检测器作了简要评述。根据所采用的检测原理。光源检测器可分为紫外检测器,激光诱导荧光检测器、化学肆光检测器、荷耦合器件检测器、折射指数检测器等许多种类,具有简单方便、使用广泛,信息量较大等特点,是一类有良好诉检测器。 相似文献
59.
Prochiral Ketones were reduced by NaBH4 in aqueous micelles formed from chiral surfactants (-)-N-alkyl-N,N-dimethylmenthylammonium bromides, giving optically active alcohols with enantioselectivity up to 17.7%. 相似文献
60.
Jingkun Xu Weiqiang Zhou Bing Chen Shouzhi Pu Jingwu Wang Yiqun Wan 《Journal of polymer science. Part A, Polymer chemistry》2006,44(3):1125-1135
Free‐standing poly(dibenzofuran) (PDBF) films were synthesized electrochemically by direct anodic oxidation of dibenzofuran in mixed electrolytes of boron trifluoride diethyl etherate (BFEE) containing certain amount of trifluoroacetic acid (TFA). The oxidation potential of dibenzofuran in pure BFEE was measured to be only 1.31 V versus saturated calomel electrode (SCE). This value was much lower than that determined in acetonitrile + 0.1 mol L?1 TBATFB (2.14 V vs. SCE). The addition of TFA to BFEE can further decrease the oxidation potential of the monomer to 1.07 V versus SCE in the mixed electrolyte of BFEE + 30% TFA. PDBF films obtained from this medium showed good electrochemical behavior, good electrochromic properties, and good thermal stability with conductivity of 100 S cm?1. FTIR and 1H NMR spectra showed that the polymer was grown mainly via the coupling of the monomer at C(3) C(10) or C(4) C(9) positions (Scheme 1). As‐formed PDBF films were partly soluble in tetrahydrofuran (THF) or chloroform. Fluorescent spectral studies indicated that either soluble or PDBF in solid state was a good blue light PDBF emitter. To the best of our knowledge, this is the first report that free‐standing PDBF films can be electrodeposited. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1125–1135, 2006 相似文献