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THE ADSORPTION OF OXYGEN OVER ThO2-BaF2 CATALYST

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Journal of Energy Chemistry 1996年第1期 22-30页

作者： ZHOU Xiao-Ping CHAO Zi-Sheng wan hui-lin tsai khi-Rui(Department of Chemistry, Xiamen University Xiamen, Fujian 361005 To whom correspondence should be addressed)

The adsorption of O2 over ThO2-BaF2 catalyst was studied at room temperature. Raman experiments reveal that there is much stronger adsorption of O2 on ThO2-BaF2 than on ThO2 XRD results suggest that ionic exchange exists between BaF2 and ThO2 phases forming the O-species and quasi-free electrons in ThO2-BaF2. The XPS, Raman and EPR results indicate that O22-, O2- and intermediate oxygen species O2n- and O2δ- (1更多还原AbstractFilter('ChDivSummary', 'ChDivSummaryMore', 'ChDivSummaryReset');

关键词： oxygen species metal fluoride ThO2-BaF2

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黄土塬边漫灌区土体水入渗过程研究

岩土力学 2024年第9期45卷 2754-2764页

作者：赵宽耀许强陈婉琳彭大雷高登辉黄淮学院河南省结构力学与数值仿真国际联合实验室河南驻马店463000 成都理工大学地质灾害防治与地质环境保护国家重点实验室四川成都610059

黄土漫灌区水入渗形成的饱和黄土层内极易产生液化型破坏,诸如积石山6.2级地震诱发的中川乡液化型黄土滑坡和甘肃黑方台黄土滑坡为典型案例;然而,黄土中水的渗流是以活塞式基质渗流为主还是以优势渗流为主,目前尚未定论。以甘肃黑方台... 详细信息

黄土漫灌区水入渗形成的饱和黄土层内极易产生液化型破坏,诸如积石山6.2级地震诱发的中川乡液化型黄土滑坡和甘肃黑方台黄土滑坡为典型案例;然而,黄土中水的渗流是以活塞式基质渗流为主还是以优势渗流为主,目前尚未定论。以甘肃黑方台典型滑坡后缘漫灌区土体为研究对象,开展现场漫灌入渗试验,借助三维高密度电法实时监测水的入渗过程;利用电阻率变化率表征水分的整体入渗过程,并用相邻测量时段电阻率变化率差值表征该时段内水分的关键渗流空间,分析漫灌作用下黄土中水的渗流模式,探讨不同补给强度对渗流模式的影响。主要得出以下结论:(1)固定电极的时序三维高密度电法能有效探测黄土中水的渗流过程;(2)试验区黄土中呈现基质流与优势流共存的渗流模式,其中基质流的均匀入渗为测量空间内的主要渗流模式且集中于近地表2m内,优势流表现为延伸至4m深度的优势通道内水分向周围以基质流形式逐渐渗流,渗流轨迹受优势通道分布的影响;(3)含裂隙黄土中水的渗流模式受水补给强度的影响,其中漫灌或降雨积水时,出露地表的裂隙内水分可直接下渗至裂隙延伸的区域形成优势流,而在无积水的降雨条件下,裂隙内无法形成明显优势流,水分以活塞式基质流的形式下渗。研究成果可为黄土中水渗流的现场观测及模式探讨提供借鉴。

关键词：黑方台黄土滑坡原位入渗试验优势流高密度电法

Synthesis of Compact NaA Zeolite Membrane by Microwave Heating Method

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Chinese Chemical Letters 2003年第8期14卷 874-876页

作者： Zhi lin CHENG Zi Sheng CHAO hui lin wan State Key Laboratory for Physical Chemistry of Solid Surface Department of ChemistryXiamen UniversityXiamen 361005

A continuous and dense NaA zeolite membrane was synthesized by microwave heating method while employing a multi-step seeding LTA zeolite with the average size of 120 nm. The gas H2/N2 mixture separating results indicated that the mixture selectivity increased with increasing of synthesis times. In addition, selectivity of the three-step synthesis was higher than the value(3.74) expected from Kundsen diffusion.

关键词： Microwave heating NaA zeolite membrane gas separation.

CuO-ZnO INTERACTION IN AHTD Cu-BASED CATALYST FOR METHANOL SYNTHESIS FROM CO/H2

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Journal of Energy Chemistry 1994年第3期 280-285页

作者： HU Yun-Hang wan hui-lin tsai khi-RuiDepartment of Cheimsbry and State Key Laboratory for Physical Cheimsbry of the Solid Sur face Xiamen University Xiamen, Fujian 361005

A CU/ZnO catalyst for methanol synthesis from CO/H, was pre-pared directly using metal nitrates by Aerosol High Temperature Decomposition（AHTD） *** the TPR of the AHTD Cu/ZnO catalyst,there were tworeduction *** results showed CuO reduction took place at least partiallyinvolving two stepe:Ch→Cuand Cu→*** the basis of the resultsof TPR,XRD,XPS and activity test,we supposed that there be an interactionbetween CuO and ZnO in AHTD Cu/ZnO catalyst.

关键词： CuO-ZnO INTERACTION IN AHTD Cu-BASED CATALYST FOR METHANOL SYNTHESIS FROM CO/H2 ZnO XRD CO

OXIDATIVE COUPlinG OF METHANE OVER Ba-La-O CATALYSTS PROMOTED WITH FLUOriNE ANION

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Journal of Energy Chemistry 1995年第1期 45-51页

作者： DAI Dong-Mei ZHOU Xiao-Ping CHAO Zi-ShengwanG Shui-Ju wan hui-lin tsai khi-RuiDepartment Chemistry, Xiamen University Xiamen, Fujian 361005

Oxidative coupling reaction of methane (OCM) was studied over Ba-La-O-F catalysts. F-anions exhibited apparent promoting effects on Ba-La-O-F catalysts for OCM reaction. Over BaF2/La2O3, C2 yield was 1 to 4 percent hi... 详细信息

关键词： oxidative coupling fluorine anion anion exchange

艾草对米酒品质的影响研究和艾草米酒发酵工艺优化

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云南民族大学学报（自然科学版） 2024年第1期33卷 50-55,62页

作者：黄瑶雁叶婉琳林继辉唐恩闽南科技学院生命科学与化学学院福建南安362332

以糯米为原料,通过优选的艾草、甜酒曲搭配,进行复合发酵,制备艾草米酒.通过测定艾草米酒的pH值、总糖、氨基酸和抗氧性能等,探讨添加艾草后所酿米酒的品质变化.试验结果表明,相对于普通米酒,艾草米酒的pH值不变,含糖量、抗氧化性等都... 详细信息

以糯米为原料,通过优选的艾草、甜酒曲搭配,进行复合发酵,制备艾草米酒.通过测定艾草米酒的pH值、总糖、氨基酸和抗氧性能等,探讨添加艾草后所酿米酒的品质变化.试验结果表明,相对于普通米酒,艾草米酒的pH值不变,含糖量、抗氧化性等都大大提高,氨基酸总体含量基本没有变化,但是其必需氨基酸的含量却有所提高,说明米酒添加艾草发酵有利于提高米酒的品质.通过单因素和响应面试验研究了艾草米酒最佳发酵工艺为艾草提取液0.17 g/mL、酒曲接种量1.41 g、发酵时间34 h,得到米酒的抗氧化性为53.58%.

关键词：艾草米酒抗氧化响应面氨基酸

Effect of electropulsing treatment on solidification behavior of spring steels in a continuous casting mold simulator

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Journal of Iron and Steel Research International 2020年第6期27卷 656-664页

作者： wan-lin wang Guo-min Ying Jie Zeng Hai-hui Zhang School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina National Center for International Research of Clean Metallurgy Central South UniversityChangsha 410083HunanChina

An electropulsing-assisted mold simulator technique was developed to investigate the effects of a pulsed electric voltage on the quality of spring steels during continuous casting by analyzing the mold flux film,shell surface profile,shell micro-structure and inclusion *** results revealed significantly increased crystallization fraction of the mold flux film from 61.2%to 75.3%and finer crystalline phase morphology in the case of electropulsing *** surface of the initially solidified shell could be effectively healed,resulting in smoother shell surface profiles with higher pulsed voltage from 0 to ***,an increase in the pulsed voltage from 0 to 30V resulted in finer dendritic structures during solidification with decreasing secondary dendrite arm spacing from the values of 17.6-32.2 to 9.7-15.0μm in the direction of shell side toward melt *** addition,an area scan analysis of inclusions in the as-cast spring steel samples showed that the number of MnS inclusions in the size range of 2.0-4.0μm gradually decreased from 836 to 114 and the number of Al2O3 inclusions in the same size range decreased from 144 to 39,as the voltage increased from 0 to 30V.

关键词： Electropulsing treatment Mold flux film Shell surface proifle Inclusion distribution Shell microstructure

Synthesis,Spectroscopic Properties and Structural Characterization of Sodium Potassium Citrato Oxotungstate(VI)Dimer

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Chinese Journal of Structural Chemistry 2000年第3期19卷 181-186页

作者： wanG Geng ZHOU Zhao-hui ZHANG hui YE Jian-Liang wan hui-lin Department of Chemistry and State Key Laboratory for Physical Chemistry of Solid Surface Xiamen UniversityXiamen361005

The sodium potassium citrato oxotungstate(VI) dimer, Na 4K 2〔W 2O 5\|(cit) 2〕·11H 2O (H 4cit = citric acid) was obtained by the reaction of sodium tungstate(VI) and excess potassium citrate monobasic (KH 3cit) in neutral solution. The crystal data for the title compound: monoclinic, C 12 H 30 K 2Na 4W 2O 30 , M r =1192.21, space group P2 1/n, a=17.427(4), b=10.022(2), c=18.637(3) , β=92.62(1)°, V=3252(2)  3, Z=4, D c =2.435 g/cm 3, μ( Mo Kα )=76.38 cm -1 , F( 000)=2288. The structure was refined to R =0.0434 for 6327 independent observed reflections with I>3σ(I) . The complex anion contains a quasi centrosymmetric (O 2W)O b(WO 2) core with a bent bridging oxo group 〔W-O b-W 175.0(4)°〕. Each citrate as tridentate ligand coordinates to a tungsten atom through the alkoxy, α carboxyl, and one β carboxyl group, while the other β carboxyl group remains uncoordinated. Principal dimensions are: W-O b 1.883(6) , (W=O t)av 1.715(6) , W-O (alkoxy) 1.959(6) , W-O ( α carboxy) 2.176(6)  and W-O ( β carboxy) 2.231(6) . The tungsten atom is located in a distorted octahedron environment.

关键词： oxotungstate(VI) citrate citric acid citrate method crystal structure

Acceptorless dehydrogenative amination of alkenes for the synthesis of N-heterocycles

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Science China Chemistry 2022年第7期65卷 1330-1337页

作者： Jia-lin Tu wan Tang Shi-hui He Ma Su Feng Liu Jiangsu Key Laboratory of Neuropsychiatric Diseases and Department of Medicinal Chemistry College of Pharmaceutical SciencesSoochow UniversitySuzhou 215123China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Catalytic amination of alkenes is one of the most attractive reactions for the construction of complex heterocycles with nitrogen centers. Herein, we present that synergistic photoredox and cobaloxime catalysis allows for highly efficient and mild dehydrogenative reactions between various NH nucleophiles and di-, tri-, and tetrasubstituted alkenes in the absence of external oxidants, thus enabling access to an array of N-heterocycles. Notably, both Z-and E-alkene-containing N-heterocycles are accessible. Mechanistic studies indicated that the Z-cinnamyl derivatives could be generated by photocatalytic E to Z alkene isomerization through an energy transfer process. Moreover, we find that sluggish energy transfer could inhibit the E to Z alkene isomerization process, thus offering the cinnamyl derivatives with E-selectivity. Our results highlight the benefits of the reactions using dual photoredox and cobaloxime catalysis to lead to diverse N-heterocycles.

关键词： nitrogen-centered radical alkene amination photoredox cyclization N-heterocycle