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41.
A microporous clay mineral with organic-inorganic hybrid pillars was synthesized using a hydrochloric acid (HCl)/ethanol extraction method after intercalation of tetraethoxysilane (TEOS) or TEOS/methyltriethoxysilane (MTS) into the cetyltrimetylammonium ion (CTA)-exchanged vermiculite. The products retained their layered structure, due to the formation of stable pillars by the polymerization of hydrolyzed TEOS and MTS during the HCl/ethanol treatment. The BET surface areas, which increased to above 500 m2g(-1) with an increase in the HCl concentration up to 0.4 moldm(-3), are nearly equal to that of the calcined product obtained by the conventional method. However, the pore sizes of HCl/ethanol-treated materials were narrower than those of the calcined product, owing to the formation of the polysiloxane networks in the gallery. A water adsorption study showed that the product treated with a TEOS/MTS mixture had a hydrophobic surface as a result of the successful incorporation of methyl groups at the surface of the pillars. This novel method is advantageous for the synthesis of organophilic pillared clays with different kinds of organic materials in the interlayers. 相似文献
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Bao-Lei Wang Qing-Nan Li Yi-Zhou Zhan Li-Xia Xiong Shu-Jing Yu Zheng-Ming Li 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):483-491
Abstract A novel series of pyrazole derivatives containing substituted phenylsulfinyl/sulfonyl group have been synthesized via the oxidation of intermediate pyrazole sulfoether with H2O2 in acetic acid. The novel compounds were characterized by melting point, 1H NMR, FT-IR, MS, and elemental analysis or HRMS. The biological activity results showed that most of the title compounds exhibit significant fungicidal activities against Alternaria solani Sorauer, Phytophthora capsici, and Corynespora cassiicola. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text and figures.] 相似文献
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Qiao-Xia Liu Ming-Zhen Mao Li-Xia Xiong Zheng-Ming Li 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):593-599
AbstractA series of novel anthranilic diamide derivatives containing pyridylpyrazole and iminodithiocarbamate or thiosemicarbazone motifs were synthesized via multi-step reactions. The structures of seven title compounds (methyl 2-(2-(3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamido)-5-chloro-3- methylbenzylidene)hydrazinecarbodithioate 7 and 3-bromo-N-(2-((2-substitutedcarbamothioylhydrazono)methyl)-4-chloro-6-methylphenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide 8a-8f) were confirmed by melting points, IR, 1H NMR, 13C NMR, and HRMS. The bioassays showed that some of the compounds exhibited modest insecticidal activities against oriental armyworm (Mythimna separata Walker), particularly, compound 8b (3-bromo-N-(4-chloro-2-methyl-6-((2-(methylcarbamothioyl)hydrazono)methyl)phenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide) held 100% and 30% larvicidal activity at the concentration of 25?mg/L and 10?mg/L, respectively. In addition, several compounds displayed favorable fungicidal activities against Alternaria solani Sorauer and Physalospora piricola at 50?μg/mL, and were comparable with the controls Chlorothalonil and Triadimefon. The results in this paper will provide important information for further research and development of sulfur-containing heterocyclic agrochemicals. 相似文献
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采用EDTA-柠檬酸盐法制备了(Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+δ(PLNCG),并与Ce0.9Gd0.1O2-δ(CGO)形成复合阴极PLNCG-CGO。XRD和SEM分析结果表明PLNCG与CGO在1 000℃具有较好的化学相容性。电化学阻抗测试结果表明PLNCG-30% CGO复合阴极在700℃的极化电阻为0.092 Ω·cm2;过电位为39.3 mV时,电流密度达到113.3 mA·cm-2。氧分压分析表明电极反应的速率控制步骤为电荷转移过程。阳极支撑单电池(Ni-CGO/CGO/PLNCG-30% CGO)在700℃的最大输出功率密度达到569 mW·cm-2,开路电压(OCV)为0.76 V。综上结果预示PLNCG-30% CGO复合阴极是一种有发展前景的电极材料。 相似文献
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The mixed-metal cluster Yb4O4(OiPr)16Na12 has been synthesized and structurally determined by IR, elemental analysis, and single-crystal X-ray diffraction. The crystal belongs to the cubic system, space group P23 with a = b = c = 13.9788(3), V = 2731.55(10)3 , Z = 1, Dc = 1.202 g/cm 3 , Mr = 1977.42, = 3.480 mm-1 , F(000) = 972, the final R = 0.0288 and wR = 0.1511 for 1677 observed reflections with Ⅰ > 2σ(Ⅰ). X-ray analysis reveals that Yb4O4 (OiPr)16Na12 is centrosym-metric and the structure contains four ytterbium metals and twelve sodium metals, and each ytterbium atom is coordinated by six oxygen atoms. In addition, an ancillary computational analysis of the optimized molecular unit was provided. The large energy gap (3.31 eV) between HOMO and LUMO indicates that the structure framework is particularly stable. 相似文献
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LUO Zha LIU Hao SHEN Wei SHI Kun CHEN Ankang SHENG Libo SUI Yongming ZOU Bo 《高等学校化学研究》2022,38(3):843-846
We used a diamond anvil cell(DAC) to control the deformation of synthesized copper nanorods and silver nanoparticles. And we measured the surface plasmon resonance of copper nanorods and silver nanoparticles, which exhibit redshifts or blueshifts. The surface plasmon resonance shows an abnormal blue shift for both copper nanorods and silver nanoparticles. The solvents of copper nanorods and silver nanoparticles are n-hexane and water, where the pressure loads include quasi-hydrostatic and non-hydrostatic. 相似文献
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