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Synthesis and Crystal Structure of Co(DMSO)_2(H_2O)_2(SCN)_2 with One-dimensional Hydrogen-bonded Structure (DMSO = Dimethylsulfoxide)

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Chinese Journal of Structural Chemistry 2006年第6期25卷 643-646页

作者： WEI Rong-Min CHE yun-xia ZHENG Ji-Min Departmentof Biology Chemistry Tianjin Normal University Tianjin 300071 China

The title complex Co（DMSO）2（H2O）2（SCN）2 has been prepared and structurally characterized. It crystallizes in monoclinic, space group P21/n with a= 5.1981（9）, b = 11.944（2）, c = 12.646（2） A,β = 98.686（2）°, V = 776.2（2） A^3, C6H16CoN2O4S4, Mr = 367.38, Z = 2, De = 1.572 g/cm^3, F（000） = 378 and μ（MoKa） = 1.646 mm^-1. The structure was refined to R= 0.0232 and wR = 0.0645 for 1241 observed reflections with I 〉 2σ（I）. In the title complex, each Co（II） atom is octahedrally coordinated by four O atoms from two DMSO ligands and two water molecules as well as two N atoms from SCN^- ions. The title molecules are connected to each other through intermolecular hydrogen bonds to form a 1-D structure extended by eight-membered Co2O4H2 rings.

关键词： dimethylsulfoxide thiocyanate group supramolecule,complex intermolecular hydrogen bond

Unsteady Flow and Structural Behaviors of Centrifugal Pump under Cavitation Conditions

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Chinese Journal of Mechanical Engineering 2019年第1期32卷 127-141页

作者： Denghao Wu yun ren Jiegang Mou yunqing Gu Lanfang Jiang College of Mechanical Engineering Zhejiang University of Technology Zhijiang College Zhejiang University of Technology

Cavitation has a significant e ect on the flow fields and structural behaviors of a centrifugal pump. In this study, the unsteady flow and structural behaviors of a centrifugal pump are investigated numerically under di erent cavitation conditions. A strong two-way coupling fluid-structure interaction simulation is applied to obtain interior views of the e ects of cavitating bubbles on the flow and structural dynamics of a pump. The renormalization-group k-ε turbulence model and the Zwart–Gerbe–Belamri cavitation model are solved for the fluid side, while a transient structural dynamic analysis is employed for the structure side. The di erent cavitation states are mapped in the head-net positive suction head(H-NPSH) curves and flow field features inside the impeller are fully revealed. Results indicate that cavitating bubbles grow and expand rapidly with decreasing NPSH. In addition, the pressure fluctuations, both in the impeller and volute, are quantitatively analyzed and associated with the cavitation states. It is shown that influence of the cavitation on the flow field is critical, specifically in the super-cavitation state. The e ect of cavitation on the unsteady radial force and blade loads is also discussed. The results indicate that the averaged radial force increased from 8.5 N to 54.4 N in the transition progress from an onset cavitation state to a super-cavitation state. Furthermore, the structural behaviors, including blade deformation, stress, and natural frequencies, corresponding to the cavitation states are discussed. A large volume of cavitating bubbles weakens the fluid forces on the blade and decreases the natural frequencies of the rotor system. This study could enhance the understanding of the e ects of cavitation on pump flow and structural behaviors.

关键词： Centrifugal pump Cavitation Unsteady flow Structural behaviors Fluid-structure interaction

Synthesis and Crystal Structure of a Three-dimensional (3D) Complex Mn(H_2O)_2(HNic)_2 (HNic=2-Hydroxynicotinic Acid)

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Chinese Journal of Structural Chemistry 2006年第5期25卷 572-576页

作者： LI Yu-Mei CHE yun-xia ZHENG Ji-Min Department of Chemistry Nankai University Tianjin 300071 China

The title complex Mn（H2O）2（HNic）2 （C22H12MnN2O8, Mr = 367.18） crystallizes in monoclinic, space group P21/c with a = 7.5735（8）, b = 12.5295（13）, c = 7.6466（8）A.β = 101.2790（10）°, Z = 2, V= 711.59（13） A^3, D, = 1.714 g/cm^3,μ（MoKa） = 0.974 mm^-1, F（000） = 374, R1 （1255 observed reflections （Ⅰ 〉 2σ（Ⅰ）） = 0.0250） and wR2 = 0.0662 （all data）. In this paper, we report the complexation of Mn（Ⅱ） by the bidentate ligand 2-hydroxynicotinic acid （HNic）. In the crystal the Mn（Ⅱ） ion exhibits a deformed octahedron structure. The title complex Mn（H2O）2（HNic）2 has a three-dimensional （3D） network structure extended by hydrogen bonds, which are formed by two typical eight-membered hydrogen-bonded rings.

关键词： complex crystal structure three-dimensional network

TiB2 coating formed on nickel substrates by electroplating in molten salt of fluoride

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中国有色金属学会会刊：英文版 2004年第z1期14卷 132-135页

作者： LONG Jin-ming GUO Zhong-cheng HAN xia-yun Faculty of Materials and Metallurgical Engineering Kunrning University of Science and Technology Kunming 650093 China Faculty of Materials and Metallurgical Engineering Kunrning University of Science and Technology Kunming 650093 China Faculty of Materials and Metallurgical Engineering Kunrning University of Science and Technology Kunming 650093 China

The TiB2 coatings deposited over nickel substrate by electroplating was investigated, which is in molten salt of a fluoride mixture involving KF, NaF, K2 TiF6 and KBF4. Effects of temperature, cathodic current density (Jc) and duration on the coating's formation were examined. The composition, morphology and structure of the coatings were characterized by scanning electron microscopy (SEM), energy dispersive X-ray detector (EDS) and X-ray diffraction (XRD). The results show that the coatings, with black, smooth and uniform appearance, are composed of predominating TiB2 and small amounts of nickel titanium oxide (Ni0.75 Ti0.125 O). The coatings show a nodular morphology and the grain size is dependent on the Jc and ranges about 1 - 10 μm. There is a linear relationship between the coating's thickness and the time of electrolysis within certain duration range. The reduction of the potassium can take place simultaneously with the electrochemical synthesis of TiB2 as the Jc is in excess of certain level. The hardness of the TiB2 coatings is likely to be deteriorated due to the presence of potassium and Ni0.75Ti0.125 O in the coatings.

关键词： TiB2 coating electroplating molten salt nickel microstructure

Synthesis and Crystal Structure of a Novel Three-dimensional Complex Ni(Iz)_2(Bdc)(H_2O)_2 (Iz = Imidazole,Bdc = 1,4-Benzenedicarboxylate)

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Chinese Journal of Structural Chemistry 2006年第7期25卷 818-822页

作者： TAN xiao-Na CHE yun-xia ZHENG Ji-Min Department of Chemistry Nankai University Tianjin 300071 China

A novel nickel（Ⅱ） complex Ni（Iz）2（Bdc）（H2O）2 （Iz = imidazole, Bdc = 1,4-benzenedicarboxylate） has been synthesized and structurally characterized by X-ray analysis. The crystal is of monoclinic, space group P2 1/n with a = 5.5079（5）, b = 15.0973, c = 9.9825（9） A, β = 90.2380（10）°, C14H16N4NiO6, Mr = 395.02, Z = 2, V = 830.08（13） A^3 Dc = 1.580 g/cm^3, μ（MoKa） = 1.208 mm^-1, F（000） = 408, R = 0.0234 and wR = 0.0603 for 1379 observed reflections （I 〉 2σ（I））. In the title complex, adjacent nickel（Ⅱ） ions are bridged through the oxygen atoms of carboxylic groups in syn-anti conformation, yielding an infinite one-dimensional chain. These chains are linked to each other to form a 3-D network structure by three kinds of hydrogen-bonding interactions.

关键词： synthesis crystal structure nickel(Ⅱ) complex 1,4-benzenedicarboxylate

Pt-H2SO4/Zr-montmorillonite： An efficient catalyst for the polymerization of octamethylcy-clotetrasiloxane, polymethylhydrosiloxane and hexamethyldisiloxane to low-hydro silicone oil

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1771-1776页

作者： Yuedong Zhou Fengfu Li Junwei Liu Zhi yun xia Gui College of Chemistry and Chemical Engineering Nanjing Tech University Nanjing 210009. China

The liquid phase ring-opening of octamethylcy-clotetrasiloxane （D4） was investigated over Pt-H2SO4/Zr- montmorillonite catalyst. Montmorillonite （Mt）, Zr-Mt, H2SO4/Mt, H2SO4/Zr-Mt and Pt-H2SO4/Zr-Mt were also detected for evaluation. The catalysts were characterized by X-ray fluorescence, X-ray diffraction, nitrogen adsorption-desorption, NH3-TPD and pyridine-FTIR measurements. In comparison to activate clay which is used in the industry of catalyst, Zr-Mt catalyst displayed stronger acidity and more excellent catalytic activity in the polymerization of D4, polymethylhydrosiloxane （DH） and hexamethyldisiloxane （MM） to low-hydro sili- cone oil. Relative to Zr-Mt, the acidity of H2SO4/Zr-Mt was noticeably improved and the catalyst exhibited a higher capability of ring-opening of D4 conversion and yield of low-hydro silicone oil. To enhance the stability of H2SO4/Zr-Mt catalyst, a small amount of metals （Pt） was doped. The nitrogen adsorption-desorption results indicated that pore textural parameters of the Pt-H2SO4/Zr-Mt had not changed with larger specific surface area. Compared with H2SO4/Zr-Mt, the total acidity of Pt-H2SO4-Zr/Mt catalyst retained, but the content of the Bransted acid increased and the content of the Lewis acid decreased. The Pt-H2SO4-Zr/Mt catalyst displayed higher catalyst reproducibility. After 40 h reaction of polymerization, the yield of low-hydro silicone oil decreased from 93% to 42% over H2SO4/Zr-Mt catalyst, while the yield of low-hydro silicone oil reduced from 93% to 78% over Pt-H2SO4/Zr-Mt catalyst. A sharp decrease in catalytic activity after 35 h of Pt-H2SO4/Zr-Mt catalyst was detected. Furthermore, Pt-H2SO4/Zr-Mt was completely regenerated under appropriate condition and appeared good repeatability in the D4, DH and MM to low-hydro silicone oil.

关键词： Pt-H2SO4/Zr-montmorillonite Low-hydro silicone oil Catalyst Stability Regeneration

Dynamical role of the Rocky Mountain controlled by East Asian topographies in modulating the tropospheric westerly jet in northern winter

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Atmospheric and Oceanic Science Letters 2019年第1期12卷 66-72页

作者： xia Xin ren Rongcai YU Yueyue State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences College of Earth Sciences University of Chinese Academy of Sciences Key Laboratory of Meteorological Disaster Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD) Nanjing University of Information Science & Technology

Large-scale mountains like Asian topographies and the Rocky Mountains have important influences on subtropical jet streams(STJs)over downstream regions in *** dynamical role of the Rocky Mountains in modulating STJs with and without the existence of East Asian(EA)topographies in northern winter is investigated via numerical *** agreement with previous studies,the Rocky Mountains(topographic forcing),with the existence of EA topographies,can only strengthen the STJ from the east coast of North America to the western Atlantic *** independent role of the Rocky Mountains,however,strengthens the STJ over not only the east coast of North America but also over Pacific *** is found that the existence of EA topographies can dramatically strengthen the EA trough,as well as a downstream ridge which,in the upstream of the Rocky Mountains,acts to partly cancel out the strengthening of the anticyclone to the north of the Rocky Mountains and the northward warm air transport in the high latitudes of Pacific regions due to the Rocky Mountains’forcing *** circulation changes effectively weaken the Rocky Mountains–forced strengthening of the meridional temperature gradient in the midlatitude North Pacific,and thus the STJ ***,EA topographies are of great importance in modulating the role of the Rocky Mountains as a dynamical forcing of STJ variability.

关键词： Rocky Mountains East Asian topographies topographic forcing subtropical jet stream

Effect of SO_2 on the performance of Ag-Pd/Al_2O_3 for the selective catalytic reduction of NOx with C_2H_5OH

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Journal of Environmental Sciences 2006年第5期18卷 973-978页

作者： XIE Shu-xia YU yun-bo WANG Jin HE Hong State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The influence of SO2 on the performance of Ag-Pd/Al2O3 for the selective catalytic reduction （SCR） of NOx with C2H5OH was investigated experimentally. The activity test results suggest that Ag-Pd/Al2O3 shows a small activity loss in the presence of SO2 when using C2H5OH as a reductant. In situ DRIFTS spectra show that the activity loss originates from the formation of surface sulphate species on the Ag-Pd/Al2O3. The surface sulphate species formation inhibits the formation of nitrate, whereas hardly changes the partial oxidation of C2H5OH. Compared with the NOx reduction by C3H6, an obvious suppression of the surface sulphate species formation was observed by DRIFTS experiment when using C2H5OH as a reductant. This phenomenon reveals the better catalytic performance and strong SO2 tolerance of Ag-Pd/Al2O3-C2H50H system.

关键词： sulphate SCR nitrate enolic species isocyanate reaction mechanism

Development of Integrated and Intelligent Geodetic and Photogrammetry Satellites with Corresponding Key Technologies

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Journal of Geodesy and Geoinformation Science 2023年第4期6卷 3-12页

作者： Yuanxi YANG xia ren Jianrong WANG State Key Laboratory of Geo-Information Engineering Xi’an 710054China Xi’an Research Institute of Surveying and Mapping Xi’an 710054China

Aerospace surveying and mapping has become the main method of global earth *** can be divided into the geodetic observation satellites and the topographic surveying satellites according to the *** this paper,the geodetic satellites and photographic satellites are introduced ***,the existing problems in Chinese earth observation satellites are analyzed,and the comprehensive satellite with integrated payloads,the intensive microsatellite constellation and the intelligent observation satellite are proposed as three different development ideas for the future earth observation *** possibility of the three ideas is discussed in detail,as well as the related key technologies.

关键词： aerospace surveying and mapping gravity satellite magnetic satellite optical mapping satellite microwave mapping satellite microsatellite networking intelligent satellite observation