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Rare Metals 2006年第4期25卷 309-315页

作者： WEN Xianming ma peihua ZHU Geqin WU Zhiming Qinghai Institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Chemical interferences （ionization and oxide/hydroxide formation） on the atomic absorbance signal of lithium in FAAS analysis of brine samples are elaborated in this article. It is suggested that inadequate or overaddition of deionization buffers can lead to loss of sensitivities under particular operating conditions. In the analysis of brine samples, signal enhancing and oxide/hydroxide formation inducing signal reduction resulting from overaddition of deionization buffers can be seen with varying amounts of chemical buffers. Based on experimental results, the authors have arrived at the optimized operating conditions for the detection of lithium, under which both ionization and stable compound formation can be suppressed. This is a simplified and quick method with adequate accuracy and precision for the determination of lithium in routine brine samples from chemical plants or R＆D laboratories, which contain comparable amounts of lithium with some other components.

关键词： analytical chemistry simplified method FAAS lithium brine deionization oxide/hydroxide formation

Study on the Host-Guest Interactions Between Tetramethyl Cucurbit[6]uril and Benzimidazole Derivatives

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Chemical Research in Chinese Universities 2023年第6期39卷 1017-1022页

作者： YANG Naqin DAI Xue ma Yue YANG Xinan ma peihua Key Laboratory of macrocyclic and Supramolecular Chemistry of Guizhou Province College of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025P.R.China

In this paper,^(1)H NMR spectroscopy,isothermal titration calorimetry,X-ray crystallography and other characterization methods were used to investigate the interaction modes of tetramethyl cucurbit[6]uril(TMeQ[6])and three benzimidazole derivatives in an aqueous solution-solid *** results showed that the aromatic ring moieties in the three derivatives all entered the cavity of TMeQ[6]and their substituents were located at the port of TMeQ[6],forming 1:1 host-guest inclusion *** crystal structures showed that the aromatic part of the benzimidazole derivatives interacted with the cavity of TMeQ[6]via hydrogen bond interactions and the N atoms on the benzimidazole ring formed hydrogen bonds with the carbonyl oxygen of TMeQ[6].The ion-dipole interactions between[ZnCl_(4)]^(2-)and TMeQ[6]formed supramolecular self-assembly entities.

关键词： Tetramethyl cucurbituril(TMeQ) Benzimidazole derivative Host-guest interaction Crystal structure

Alkali Induced Morphology and Property Improvements of TiO_2 by Hydrothermal Treatment

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Journal of Wuhan University of Technology(materials Science) 2008年第4期23卷 503-506页

作者： HE Qiong WEN Xianming ma peihua DENG Xiaochuan Qinghai Institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Alkali induced morphology and property improvements of TiO2 by hydrothermal reaction were investigated. The products were characterized by SEM, TEM, XRD, TG, EDX, FT-IR and DRS. The results indicate that, with the phase transformation from anatase to rutile, the morphologies changed from high aggregated particles to nanofibers with the diameter of about 100 nm and the length up to several tens of micrometers, meanwhile the process is controllable by manipulating the nature of the alkali, alkalinity and hydrothermal temperature. DRS analysis shows the property improvement of the nanofibers in the UV-Vis light absorption compared with the raw materials, implying the products have potential application in photocatalysis.

关键词： rutile nanofiber hydrothermal photocatalysis

Mesoporous Ti-Mo Mixed Oxides Catalyzed Transformation of Carbohydrates into 5-Hydroxymethylfurfural

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China Petroleum Processing & Petrochemical Technology 2017年第1期19卷 26-32页

作者： Zhang Qiuyun Wei Fangfang Luo Dan ma peihua Zhang Yutao School of Chemistry and Chemical Engineering Anshun University Anshun 561000 Special and Key Laboratory of Functional materials and Resource Chemistry of Guizhou Provincial Education Department Anshun University Anshun 561000 School of Chemistry and Chemical Engineering Guizhou University Guiyang 550025

Mesoporous Ti-Mo mixed oxides were prepared via a facile approach using stearic acid as the template, and were characterized using XRD FT-IR, nitrogen adsorption-desorption isotherm and TEM techniques. The catalytic activity of the prepared mesoporous Ti-Mo mixed oxides was first evaluated for the dehydration of fructose to 5-hydroxymethylfurfural(HMF), and a 50.3% yield of HMF was obtained within 60min at 120℃. Moreover, moderate yields of HMF could also be achieved from glucose and sucrose. The mesoporous catalyst could be simply separated from the reaction mixture after termination of the reaction and reused five times with no significant loss of catalytic activity.

关键词： mesoporous catalyst solid acid heterogeneous catalysis carbohydrate 5-hydroxymentylfurfural(HMF)

ZrOCl_2·8H_2O: An Efficient and Cheap Catalyst for Esterification of Free Fatty Acids to Methyl Esters

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China Petroleum Processing & Petrochemical Technology 2014年第1期16卷 40-44页

作者： Cai Jie Zhang Qiuyun Huang Congmin Zhou Kaizhi ma peihua School of Science Guizhou University School of Chemistry and Chemical Engineering Guizhou University

The esterification of lauric acid with methanol could be efficiently catalyzed by ZrOCl2·8H2O, and this reaction was studied to develop a green method for biodiesel production. The influencing factors, such as amount of catalyst, reaction time and molar ratio of acid to methanol, were investigated. The results indicated that the ZrOCl2·8H2O catalyst showed high catalytic activity, and gave a 97.0% methyl laurate conversion rate under the following optimized conditions, viz.: a lauric acid/methanol molar ratio of 1:10, a catalyst dosage of 4%, and a reaction duration of 2 h at methanol refluxing temperature. The catalyst could be easily recovered while its activity could be well retained after three cycles. The ZrOCl2·8H2O catalyst also exhibited excellent catalytic activity for the esterification of different free long-chain fatty acids(including nonedible oils with high acid value) with different short carbon chain alcohols. Therefore, the ZrOCl2·8H2O catalyst has good potential for the synthesis of biodiesel from low-cost feedstocks such as waste vegetable oils and non-edible oils.

关键词： lauric acid inorganic salt esterification biodiesel

Host-Guest Interactions of Cyclopentanocucurbit[6]uril with Alkyl Imidazolium Hydrochlorides

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Chemical Research in Chinese Universities 2021年第3期37卷 674-678页

作者： GAO Jie MENG Ye ZHAO Weiwei JIANG Daofa ZHENG Jun YANG Xinan ma peihua Key Laboratory of macrocyclic and Supramolecular Chemistry of Guizhou Province College of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang550025China

The host-guest interactions between cyclopentanocucurbit-[6]uril(CyP_(6)Q[6])as host and six alkyl imidazolium hydrochloride as guests(g1,g2,g3,g4,g5,and g6)have been studied by various techniques,such as^(1)H NMR spectroscopy,isothermal titration calorimetry,mass spectrometry,and single-crystal X-ray diffraction *** experimental results showed that CyP6Q[6]formed 1:1 inclusion complexes with each of guests *** part of the guest entered the cavity of CyP_(6)Q[6]changes as the alkyl chain increases in *** can be seen that the length of the alkyl chain plays a key role in determining the mode of host-guest interactions.

关键词： Host-guest chemistry Cucurbituril Alkyl imidazolium salt Inclusion complex

Acid Value Determination and Pre-Esterification of Crude Euphorbia lathyris L. Oil

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World Journal of Engineering and Technology 2015年第2期3卷 70-75页

作者： Qiuyun Zhang Jinfeng Wu peihua ma Jie Cai Yutao Zhang School of Chemistry and Chemical Engineering Anshun University Anshun China Special and Key Laboratory of Functional materials and Resource Chemistry of Guizhou Provincial Education Department Anshun University Anshun China School of Chemistry and Chemical Engineering Guizhou University Guiyang China School of Science Guizhou University Guiyang China

There were various problems in the determination of oil acid value of the national standard method, and this paper developed a low cost, simple and effective way to determine the acid value of oil and grease. Furthermore, the esterification of high acid Euphorbia lathyris L. oil (ELO) with methanol could be efficiently catalyzed by hydrochloric acid to produce biodiesel, and the influencing factors such as the amount of catalyst, reaction time, reaction temperature and molar ratio of oil to methanol were also studied. Under the optimized conditions with the oil to methanol molar ratio of 1:30 and a reaction temperature of 70℃, 95.8% oil conversion was obtained within 40 min in the presence of only 2.0 wt% of catalyst. Therefore, the low-cost non-edible Euphorbia lathyris L. oil as a raw material had good potential for the synthesis of biodiesel in industry.

关键词： Acid Value Pre-Esterification Euphorbia lathyris L. Oil Biodiesel

LITHIUM RESOURCES IN CHINA'S SALT LAKES & ITS SUSTAINABLE DEVELOPMENT

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Bulletin of the Chinese Academy of Sciences 1999年第4期13卷 225-229页

作者： ma peihua & Zhang Pengxi(Qinghai Institute of Salt Lakes, CAS)

This article gives an introductory exposition of the growing demands of lithium on the market against the background of current rapid S&Tprogress and booming economic development, the worldwide trend in the production of lithium salts and the rich lithium reserves in China’s salt lakes as well as the brilliant prospects for its exploitation in the future. The article proposes that a sustainable exploitation of the lithium trove from these salt lakes should be rooted in comprehensive utilization of the trove and take a long-term approach, emphasizing high value proliferation in developing quality lithium-based products. Also, it expresses some tentative ideas on building demonstration bases for all-round exploitation and utilization of the salt lake resources and the development of lithium cells.

关键词： ITS SUSTAINABLE DEVELOPMENT In LITHIUM RESOURCES IN CHINA’S SALT LAKES

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晶须概念的泛化与学术影响

化学通报 2007年第9期70卷 691-694页

作者：乌志明马培华中国科学院青海盐湖研究所

最初只称单晶短纤维为晶须,稍后结晶较好的多晶纤维也被称为"晶须",现在无定形纤维也归进了晶须专著,通过对晶须概念泛化过程的反思,希能澄清学术著作中10多年来相沿的一个模糊认知。

关键词：晶须纤维

Minimizing chemical interference errors for the determination of lithium in brines by flame atomic absorption spectroscopy analysis

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北京科技大学学报 2006年第8期28卷 732-732页

Chemical interferences (ionization and oxide/hydroxide formation) on the atomic absorbance signal of lithium in FAAS analysis of brine samples are elaborated in this article. It is suggested that inadequate or overaddition of deionization buffers can lead to loss of sensitivities under particular operating conditions. In the analysis of brine samples,signal enhancing and oxide/hydroxide formation inducing signal reduction resulting from overaddition of deionization buffers can be seen with varying amounts of chemical buffers. Based on experimental results,the authors have arrived at the optimized operating conditions for the detection of lithium,under which both ionization and stable compound formation can be suppressed. This is a simplified and quick method with adequate accuracy and precision for the determination of lithium in routine brine samples from chemical plants or R&D laboratories,which contain comparable amounts of lithium with some other components.

关键词：分析化学简便方法锂火焰原子吸收光谱法