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Effects of different introduction methods of Ce^4+and Zr^4+on denitration performance and anti-K poisoning performance of V2O5-WO3/TiO2 catalyst

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Journal of Rare Earths 2020年第11期38卷 1207-1214,I0003页

作者： Jun Cao Xiaojiang Yao Li Chen Keke Kang Min Fu Yang Chen Research Center for Atmospheric Environment Key Laboratory of Reservoir Aquatic Environment of CASChongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China Chongqing Key Laboratory of Catalysis and New Environmental Materials College of Environment and ResourcesChongqing Technology and Business UniversityChongqing 400067China

The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reduction of NOx by *** different methods,namely pre-impregnation,post-impregnation,coimpregnation,and co-precipitation,were used to synthesize a series of V2 O5-WO3-TiO2-CeO2-ZrO2 *** catalysts were characterized by XRD,BET,NH3-TPD,XPS,and H2-TPR ***,the activity and anti-K poisoning performance were tested by an NH3-SCR model *** results show that the introduction of Ce^4+and Zr^4+can improve the catalytic performance of V2O5-WO3/TiO2 catalyst,but the impregnation method cannot enhance the anti-K poisoning ***^4+and Zr^4+introduced by co-precipitation method can effectively improve the tolerance of K,which is mainly due to the incorporation of Ce^4+and Zr^4+into TiO2 lattice to form a uniform TiO2-CeO2-ZrO2 solid solution,resulting in the optimal surface acidity and redox performance,and reducing the decreases caused by ***,based on the best introduction method,we further optimized the molar ratio of Ce^4+/Zr^4+,It is found that the catalyst exhibits the best anti-K poisoning performance when the molar ratio of Ce^4+/Zr^4+is 2:1.

关键词： V2O5-WO3/TiO2 denitration catalyst Ce^4+,Zr^4+modification Introduction methods molar ratio Anti-K poisoning performance Rare Earths

Synthesis and characterization of CaAl_xO_y:Eu^(2+) phosphors prepared using solution-combustion method

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Journal of Rare Earths 2010年第S1期28卷 272-276页

作者： F.B.Dejene D.B.Bem H.C.Swart Department of Physics University of the Free State(Qwaqwa Campus)Private Bag X13Phuthaditjhaba9866South Africa Department of Physics University of the Free StateP.O.Box 339Bloemfontein9300South Africa

Europium-doped calcium aluminate(CaAlxOy:Eu2+) phosphors were obtained at low temperatures(500 oC) by the solution-combustion of corresponding metal nitrate-urea solution *** particle size and morphology and the structural and luminescent properties of the as-synthesized phosphors were examined by means of scanning electron microscopy(SEM),X-ray diffraction(XRD),Auger spectroscopy,transmission electron spectroscopy(TEM) and photoluminescence(PL).It was found that the Ca:Al molar ratios showed greatly influence not only on the particle size and morphology,but also on their PL spectra and *** the Ca:Al molar ratios increasing from 6:100 to 26:100,the structure of as-synthesized phosphor changed from CaAl12O19 to monoclinic CaAl2O4 and the dominant emitting light from red to blue,implying that the oxidation state of doped europium ions changed from trivalent to divalent due to the structure variation of host lattice.A blue phosphor with almost pure phase can be easily prepared by solution combustion method with suitable Ca:Al molar ratio.

关键词： CaAlxOy:Eu2+ solution-combustion molar ratio structure luminescence rare earths

Characteristics of nutrients in the Jiulong River and its impact on Xiamen Water, China

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Chinese Journal of Oceanology and Limnology 2013年第5期31卷 1055-1063页

作者：陈宝红暨卫东陈金民林彩黄海宁霍云龙纪贤标 Third Institute of Oceanography State Oceanic Administration College of Information Science and Technology Xiamen University

Water samples were collected at 20 sites on 4 occasions in 2009 （twice in May, and once in both August and November） along the Jiulong River, South China to examine how nutrient inputs from the Jiulong River could affect the nutrient status of the Xiamen Water. Samples were analyzed for nitrite （NO2-N）, nitrate （NO3-N）, ammonium （NH4-N）, phosphate （PO4-P）, silicate （SiO3-Si）, salinity, and temperature, to determine the nutrient and trophic status of the river. The results indicate that nutrients are derived mainly from river runoff. NO3-N was the main form of DIN in most parts of the river. In addition, NO3-N, DIN, and SiO3-Si behave conservatively. There is a surplus of DIN and SiO3-Si in the river, and PO4-P is a limitation on phytoplankton growth. The concentration of DIN is typically above 0.60 mg/dm3, and higher than 1.00 mg/dm3 in most parts of the river. The concentration of PO4-P is typically above 0.02 mg/dm3, while the concentration of SiO3-Si is higher than 1.00 rag/din3. Between 2003 and 2008, samples were collected 3 times per year （May, August and November） at 27 sites in the Xiamen Water and analyzed for NO2-N, NO3-N, NH4-N, PO4-P, salinity, and temperature. We discovered that the Jiulong River was the key source of DIN into the Xiamen Water, but not PO4-P, indicating the reason of the N/P molar ratio imbalance in the Xiamen Water. In the future, the effects of high DIN concentrations on the phytoplankton communities and marine ecosystems of the Xiamen Water shall be studied.

关键词： nutrient molar ratio eutrophication N enrichment the Jiulong River

Hydrothermal Synthesis,Structure and Characterization of a New 2D Co(Ⅱ) Coordination Polymer Based on Flexible Double Imidazole Derivative and Oxalate

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Chemical Research in Chinese Universities 2012年第6期28卷 942-946页

作者： LIU Lian-li HUANG Jing-jing WANG Xiu-li LIU Guo-cheng YANG Song MU Bao Silicon Materials Engineering Technology Research Centre of Liaoning Province Department of Chemistry Bohai University Jinzhou 121000 P. R. China

A 1D supramolecular compound [dmbbbi]（1） and a 2D cobalt coordination polymer [Co（dmbbbi）（ox）] 2（2） [dmbbbi=1,1-（1,4-butanediyl）bis（5,6-dimethylbenzimidazole）,ox=oxalate],C48H52Co2N8O8,were obtained under hydrothermal conditions by tuning the molar ratio of the *** crystal structure analysis reveals that in compound 1,the adjacent dmbbbi molecules connect with each other via hydrogen bonds to form a 1D supramolecular *** compound 2,two crystallographically independent Co2＋ ions show the same six-coordination *** Co2＋ ion is coordinated by four oxygen atoms from two ox anions and two nitrogen atoms from two cis-dmbbbi *** adjacent Co2＋ ions are bridged by ox anions to generate an infinite 1D zigzag chain,which is extended by pairs of dmbbbi ligands to form a 2D honeycomb-like（6,3） ***,the thermal stability and the electrochemical property of compound 2 were studied.

关键词： Hydrothermal synthesis Crystal structure molar ratio Double imidazole derivative

Chemical equilibrium controlled synthesis of polyoxymethylene dimethyl ethers over sulfated titania

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Journal of Energy Chemistry 2015年第2期24卷 239-244页

作者： Huaju Li Huanling Song Feng Zhao Liwei Chen Chungu Xia Laboratory for Nano-Catalytic Material & Technology Division of Advanced Nano?materials Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of Sciences State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences i-Lab Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences

The chemical equilibrium and reaction kinetic behavior in the synthesis of polyoxymethylene dimethyl ethers （DMMn） were investigated over sulfated titania in order to reveal the decisive factor controlling the reaction. The results showed that the molar ratio of adjacent DMMn products in equilibrium solution had the same value, which depended absolutely on the reaction temperature. Meanwhile, the reactions had the same DMMn products distributions under varied reaction conditions. The equilibrium constants of the related step-wise reactions for DMMn formation were equal, which were calculated based on the bulk compositions of the reaction solution. And thus, the selectivity to DMMn was mainly controlled by the chemical equilibrium, i.e., thermodynamic control. In brief, the present results provide some guidance for future synthesis of DMMn.

关键词： polyoxymethylene dimethyl ethers sulfated titania chemical equilibrium reaction kinetic molar ratio

Formation and Characteristics of Acrylonitrile/Urea Inclusion Compound

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Chinese Journal of Chemical Physics 2013年第2期26卷 198-202,I0004页

作者：邹均庭王雨松庞文民石磊鲁非中国科学技术大学合肥微尺度物质科学国家实验室筹合肥230026

The formation process and composition of the acrylonitrile/urea inclusion compounds （AN/UIC） with different aging times and AN/urea molar feed ratios are studied by differential scanning calorimetry （DSC） and X-ray diffraction （XRD）. It is suggested that DSC can determine the guest/host ratio and the heat of decomposition. Meanwhile, the guest/host ratio and heat of decomposition are obtained, which are 1.17 and 5361.53 J/mol, respec- tively. It is suggested AN molecules included in urea canal lattice may be packed flat against each other. It is found that the formation of AN/UIC depends on the aging time. XRD results reveal that once AN molecules enter urea lattice, AN/UIC are formed, which possess the final structure. When AN molecules are sufficient, the length of AN molecular arrays in urea canals increases as aging time prolonging until urea tunnels are saturated by AN.

关键词： Acrylonitrile Urea inclusion compound molar ratio Heat of decomposition,Formation process

Study on the Synthesis Process of Dibenzylidene Sorbitol and Derivative

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Chemical Research in Chinese Universities 2001年第Z1期17卷 87-88页

作者： Li JiChun Petrochemical Research Institute of Lanzhou Petrochemical Company PetroChina

Dibenzylidene Sorbitol (DBS) and Di(P-methylbenzylidene) Sorbitol (P-MeDBS) derivatives, used as crystallinity Polyolefine kind resin transparency nucleating agent, can reduce to a large extent the product's haze, improve its transparency, validly resin's rigidity, heat resistant temperature and modulus of bending. Its good transparency and glossiness are as good as transparent material. It has become polyolefine processing auxiliary that develop most quickly and consume most massively in the world. It is used widely in the processing of transparent plastic package vessel, equipment's parts, file folder and transperene material. The nucleating agent of DBS analog is made from one mole Sorbitol and two mole benzaldehyde dehydration condensation reaction, which associates with by-reaction. Sorbitol containing six hydroxyl group ring condensates with benzaldehyde and yield three acetal compounds-monobenzylidene Sorbitol(hereafier briefly referred to as "MBS”), DBS and Tridibenzylidene Sorbitol(hereafter briefly referred to as "TBS”). MBS and TBS are by-products. The experiment is carried out under the condition of temperature 75'C, reaction time 4 hours and agitation velocity 370 r/min. We conducted intensive research on the effects of Sorbitol/benzaldehyde(S/B) and Sorbitol/P-Me-DBS feeding molar ratios. When B/S is 2, the target product's yield can even be improved to 98.5% and 97.17% respectively, whereas feeding molar ratio are increased or reduced, the product's yield reduces definitely. The reason is that DBS and Derivative are produced by the process that one mole Sorbitol and two mole benzaldehyde condense. Sorbitol can't react validly with the molar ratio being lower than 2 .While B/S is in excess of 2.1, the excess benzaldehyde condenses some yielded DBS and produces TBS. Research data show that feeding molar ratio ought to range from 1.9 to 2.1 in order to acquire high yield and selectivity's target product. The result of synthesizing P-Me-DBS homologue's mo

关键词： molar ratio nucleating agent condensation reaction modulus of high yield group ring the world in order

Higher alcohol synthesis over Cu-Fe composite oxides with high selectivity to C_(2+)OH

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Journal of Energy Chemistry 2013年第1期22卷 107-113页

作者： Zhenghong Bao Kang Xiao Xingzhen Qi Xinxing Wang Liangshu Zhong Kegong Fang Minggui Lin Yuhan Sun Low-Carbon Conversion Center Shanghai Advanced Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences

Cu-Fe composite oxides were prepared by co-precipitation method and tested for higher alcohol synthesis from syngas. The selectivity to C2＋OH and C6＋OH in alcohol distribution was very high while the methane product fraction in hydrocarbon distribution was rather low, demonstrating a promising potential in higher alcohols synthesis from syngas. The distribution of alcohols and hydrocarbons approximately obeyed Anderson-Schulz-Flory distribution with similar chain growth probability, indicating alcohols and hydrocarbons derived from the same intermediates. The effects of Cu/Fe molar ratio, reaction temperature and gas hourly space velocity （GHSV） on catalytic performance were studied in detail. The sample with a Cu/Fe molar ratio of 10/1 exhibited the best catalytic performance. Higher reaction temperature accelerated water-gas-shift reaction and led to lower total alcohols selectivity. GHSV showed great effect on catalytic performance and higher GHSV increased the total alcohol selectivity, indicating there existed visible dehydration reaction of alcohol into hydrocarbon.

关键词： higher alcohol synthesis syngas Cu-Fe composite oxides molar ratio GHSV

177Hf as a Competitor in the Synthesis of 177Lu-DOTAtate

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Journal of Chemistry and Chemical Engineering 2016年第5期10卷 238-240页

作者： Jose de Souza Caldeira Filho Centro de Tecnologia das Radiacoes. Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN/SP. Av.

This study reveals the interference of 177Hf, a decay product of 177Lu, in the synthesis of 177Lu-DOTAtate, In the experiments we followed three 177Lu t1/2. The molar ratio Lu： DOTAtate used was calculated for each decay, in two situations： 1） without considering the influence of 177Hf; 2） considering the influence of 177Hf. The results compare both the calculated molar ratio and the radionuclide incorporation yields （%） in these situations. The yields increase when 177Hf influence is considered. This suggests that 177Hf is an important competitor for DOTAtate binding site. These data are relevant in the synthesis of the radiopharmaceutical 177Lu-DOTAtate with high specific activity.

关键词： Hafnium 177Lu-DOTAtate molar ratio radiopharmaceutical.