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Synthesis, Crystal Structure and Magnetic Properties of Two Ribbon-shaped Chalcogenidometalate Complexes(Butyl-Sn)4S8M2(TEPA)2(M = Mn, Ni)

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Chinese Journal of Structural Chemistry 2020年第8期39卷 1503-1508,1361页

作者： LAI Heng-Dong LIN qi-pu State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China

Under solvothermal conditions,two ribbon-shaped chalcogenidometalate coordination compounds(butyl-Sn)4S8M2(TEPA)2(M=Mn(1),Ni(2),TEPA=tetraethylenepentamine),have been synthesized and characterized by elemental analysis,energy dispersive X-ray,infrared/ultraviolet-visible spectroscopy,thermogravimetric analysis,single-crystal and powder X-ray *** 1 and 2 crystallize in the triclinic space group P1 with a=13.999(3),b=14.658(4),c=16.150(4)A,a=68.78(3)°,β=69.12(3)°,γ=72.07(3)°,V=2825.0(14)A3,Z=2,Mr=1448.28,μ=2.503 mm-1,F(000)=1444,GOOF=1.001,R=0.0629 and wR=0.1286 for 12855 observed reflections with I>2σ(I)for 1;and a=11.029(3),b=11.858(2),c=11.888(3)A,a=87.27(2)°,β=69.10(2)°,γ=83.63(2)°,V=1443.6(6)A^3,Z=1,Mr=1455.78,μ=2.660 mm^-1,F(000)=728,GOOF=1.017,R=0.0464 and wR=0.1185 for 9267 observed reflections with I>2σ(I)for 2,*** 1 and 2 are composed of linear hexamer{Sn4M2}(M=Mn for 1,and Ni for 2)with 8μ2-S2-bridges and 2 TEPA terminal *** the quite large inter-paramagnetic-cation spacing(dMn-S-Sn-S-Sn-S-Sn-S-Sn-S-Mn=13.485 A,dNi-S-Sn-S-Sn-S-Sn-S-Sn-S-Ni=14.078 A),two samples exhibit distinct ferromagnetic-like behaviors with the intradimer coupling constant(J)and Weiss(θ)values up to 6.8 cm^-1 and 8.5 K for 1 and 17.2 cm-1 and 21.1 K for 2 calculated from the temperature dependence of the magnetic susceptibility.

关键词： chalcogenidometalates organotin-sulfides linear complexes magnetic properties

CHARACTERISTICS OF PRESSURE DROP AND CORRELATION OF FRICTION FACTORS FOR SINGLE-PHASE FLOW IN ROLLING HORIZONTAL PIPE

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Journal of Hydrodynamics 2009年第5期21卷 614-621页

作者： ZHANG Jin-hong YAN Chang-qi GAO pu-zhen College of Nuclear Science and Technology Harbin Engineering University Harbin 150001 China

Gas-liquid two-phase flow occurs increasingly in some dynamic devices operating in the oceanic condition. The relative data are limited with respect to flow characteristics, so the present study is to investigate systematically single-phase pressure drop, and to develop the theory for frictional factor under the roiling condition. Using deionized water as the test fluid, a series of experiments of single-phase flow were conducted in pipe with the inner diameter of 34.5 ram. The test section was horizontally settled on the rolling apparatus, and its regularity was similar to simple harmonic motion. It is found that the pressure drop during rolling motion fluctuate with the change of the rolling period and rolling angle, which is significantly different from fluid motion in a steady state. By the contrast between experiment results and stable-state theory values, existing correlations can not predict present frictional factor very well. Therefore, in the present article, the single-phase frictional factor is correlated with the Reynolds number for rolling motion, and its computated results agree well with experimental data.

关键词： single-phase flow pressure drop friction factor horizontal pipe rolling motion

RECONSTRUCTION OF PRECIPITATION SERIES AND ANALYSIS OF CLIMATE CHANGE OVER PAST 500 YEARS IN NORTHERN CHINA

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Journal of Hydrodynamics 2005年第6期17卷 737-745页

作者： RONG Yan-shu TU qi-pu College of water Resources and Environment Hohai University Nanjing 210098 China Tianjin Institute of Meteorological Science Tianjin 300074 China Nanjing University of Information Science and Technology Nanjing 210044 China

It is important and necessary to get a much longer precipitation series in order to research features of drought/flood and climate change. Based on dryness and wetness grades series of 18 stations in Northern China of 533 years from 1470 to 2002, the Moving Cumulative Frequency Method （MCFM） was developed, moving average precipitation series from 1499 to 2002 were reconstructed by testing three kinds of average precipitation, and the features of ell mate change and dry and wet periods were researched by using reconstructed precipitation series in the present paper. The results showed that there were good relationship between the reconstructed precipitation series and the observation precipiration series sincc 1954 and their relative root mean-square error were below 1.89%, that the relation between reconstructed series and the dryness and wetness grades series were nonlinear and this nonlinear relation implied that reconstructed series were reliable and could became foundation data for researching evolution of the drought and flood. Analysis of climate change upon reconstructed precipitation series revealed that although drought intensity of recent dry period from mid- dle 1970s of 20th century until early 21st century was not the strongest in historical climate of Northern China, intensity and duration of wet period was a great deal decreasing and shortening respectively, climate evolve to aridification situa- tion in Northern China.

关键词： reconstruction series dryness and wetness grades series precipitation series climate change Northern China

Synthesis, Crystal Structure and Gas Adsorption of a Trimeric Nickel-based Coordination Polymer

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Chinese Journal of Structural Chemistry 2019年第3期38卷 345-350页

作者： WANG Min ZHUO Chao HE Liang LIN qi-pu State Key Laboratory of Structural chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences College of Chemistry and Materials Science Fujian Normal University

A trimeric porous coordination framework [Ni_3(TPTC)(IN)_2(μ_2-H_2O)_2(CH_3OH)_2)]n· x(solvents)(1, TPTC = terphenyl-3,3?,5,5??-tetracarboxylic acid, IN = isonicotinic acid) was synthesized and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, single-crystal and powder X-ray diffraction. It crystallizes in monoclinic space group C2/c with a = 33739(12), b = 14.820(5), c = 13.568(5) ?, β = 97.388(6)o, V = 6728(4) ?3, Z = 4, Mr = 965.35, Dc = 0.953 g·cm^(-3), F(000) = 1955.5, μ = 0.881 mm^(–1), GOOF = 1.072, the final R = 0.0859 and w R = 0.2424 for 5284 observed reflections with I > 2σ(I). The structure of 1 is constructed from the linkage of trinuclear {Ni_3} second building units through TPTC and IN spacers, forming a 4,8-connected network of Schl?fli symbol {32.42.52}{34.***.58.68.72}. The CO2 uptake values for 1 are 97.9 m^2·g^(-1) at 273 K and 66.2 m^2·g^(-1) at 298 K, while its N_2 adsorption values are 8.5 m^2·g^(-1) at 273 K and 4.9 m^2·g^(-1) at 298 K, respectively. These results show that 1 has high CO_2/N_2 adsorption selectivity at ambient conditions.

关键词： trimeric nickel complex crystal structure gas adsorption

CHARACTERISTICS OF THE INTERANNUAL AND INTERDECADAL TIMESCALES OF EVAPORATION IN NORTHERN CHINA IN THE RECENT 115 YEARS

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Journal of Hydrodynamics 2006年第5期18卷 593-596页

作者： RONG Yan-shu TU qi-pu DUAN Li-yao College of Water Resources and Environment Hohai University Nanjing 210098 China Tianjin Institute of Meteorological Science Tianjin 300074 China Tianjin Institute of Meteorological Science Tianjin 300074 China Nanjing University of Information Science and Technology Nanjing 210044 China Tianjin Climate Centre Tianjin 300074 China

Evaporation plays an important role in water balance on the land surface. In Northern China, the evaporation series of the recent 115 years was reconstructed on the basis of Yhornthwaite evaporation formula. The characteristics of the reconstructed series were analyzed using 10-year running mean filter, power spectrum method, and running t-text of abrupt changes on the paper. The results showed that there were remarkable interannual fluctuations with timescales of about quasi-8-year, 3-4-year, and quasi-2-year, and interdecadal oscillations with timescales of 57.5-year, quasi-23-year, and l l.5-year. Meanwhile, the abrupt changes of the evaporation series were also of interdecadal timescale. Either interannual fluctuations or interdecadal oscillations of evaporation were closely related to variations in air temperatures and precipitation.

关键词： reconstructed evaporation series interannual timescale interdecadal timescale Northern China

Syntheses and Structures of Two Zn-Pyrazole/carboxyl Coordination Frameworks

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Chinese Journal of Structural Chemistry 2021年第10期40卷 1265-1270页

作者： OU YANG Chen-Hao WEI Zi-Juan HE Liang GUO Yu-Jun LUO Ming-Bu LIN qi-pu College of Chemistry Fuzhou UniversityFuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Two pyrazole-based zinc(Ⅱ) metal-organic frameworks,[Zn_(4)(PDC)_(2)(BDC)(H_(2)O)_(2)]_(n) (compound 1,PDC=1H-pyrazole-3,5-dicarboxylic acid,BDC=benzene-1,4,-dicarboxylic acid) and[Zn_(3)(PDC)_(2)(BPY)_(3)(H_(2)O)_(2)]_(n)(compound 2,BPY=4,4-bipyridine),were synthesized and characterized by X-ray diffraction,elemental analysis,thermogravimetric analysis,infrared and fluorescence *** 1 crystallizes in space group Pna2_(1) with a=14.325(3),b=10.004(2),c=16.454(3)Å,V=2357.8(8)Å^(3),Z=4,M_(r)=821.83,D_(c)=2.298 g·cm^(-3),F(000)=1608,GOOF=1.163,the final R=0.0218 and w R=0.0686 for 5150 observed reflections with I>2σ(I).Compound 2crystallizes in monoclinic space group C2/c with a=17.034(2),b=11.6313(9),c=11.7608(13)Å,V=2034.9(4)Å^(3),Z=2,Mr=1006.91,D_(c)=1.643 g·cm^(-3),F(000)=1020,GOOF=1.084,the final R=0.0320 and wR=0.0768 for 2435 observed reflections with I>2σ(I).

关键词： pyrazole-carboxyl X-ray crystallography metal-organic frameworks luminescence

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A Stable Luminescent MOF Constructed by Bis-(4-pyridyl)thiazolo[5,4-d]thiazole Containing Multi-electron Donor-acceptor Core

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Chinese Journal of Structural Chemistry 2021年第5期40卷 610-614,529页

作者： LI Zeng-Hui HE Liang GUO Yu-Jun LUO Ming-Bu LIN qi-pu State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China

Constructed from 2,5-bis(4-pyridyl) thiazolo[5,4-d]thiazole(Py_(2) TTz),sulfate anions and metal ions Cd(Ⅱ),a new 3D luminescent metal-organic framework(LMOF) with good water stability is synthesized under solvothermal condition.[Cd(Py_(2) TTz)(SO_(4))]_a(Py_(2) TTz=2,5-bis(4-pyridyl) thiazolo[5,4-d]thiazole).It crystallizes in tetragonal space group P42_1 m_with a=6.830(3),b=6.830(3),c=17.676(12) A,V=824.5(8) A^(3),Z=4,M_(r)=504.83,D_(c)=2.033 g·cm^(-3),F(000)=496,GOOF=1.088,the final R=0.0434 and wR=0.0948 for 6301 reflections with I>2σ(Ⅰ).Upon excitation at 370 nm,the emission peak of the compound appears at 455 nm,which has a slight redshift compared to the free ligand Py_(2) *** compound has potential to be a luminescence sensing material.

关键词： thiazolo-thiazole X-ray crystallography water-stability luminescence

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拥挤交通网络中交通分配和信号控制的组合

同济大学学报（自然科学版） 2006年第7期34卷 904-908页

作者：周溪召蒲琪上海海事大学经济管理学院上海200135 同济大学城市轨道交通研究院上海200331

提出交通网络中交通分配和信号配时的组合模型.模型被表示为两层规划.低层表示具有排队约束的Wardrop均衡模型,预测驾驶员对信号控制模式如何响应.上层确定最优信号控制以达到网络出行时间最小.

关键词：交通网络均衡分配信号控制绿信比

Electrochemical Behavior of Steel Bar in Electrolytes:Influence of pH Value and Cations

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Journal of Wuhan University of Technology(Materials Science) 2011年第6期26卷 1133-1136页

作者：濮琦 College of Mechanics and Materials Hohai University

Steel bar corrosion on electrolytes and the influence of cation were investigated. Three electrolytes of Ca（OH）2, NaOH and KOH with pH levels of 12.5, 11.5, 10.5, 9.5, 8.5 were prepared, meanwhile, the methods of free corrosion potential and electrochemical impedance spectra （EIS） were used to evaluate the influence of cations on the depassivation of the steel bar in electrolytes. The experimental results indicate that the initial corrosion pH value of the steel bar is influenced by the cation in electrolyte and the influence of K＋ in electrolyte is the most remarkable, followed by Na＋ and Ca2＋. The initial corrosion pH values are 10.5 in KOH electrolyte, 9.5 in NaOH electrolyte and lower than 8.5 in Ca（OH）2 electrolyte.

关键词： steel bar corrosion cation pH value