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Measurement and correlation of the solid-liquid equilibrium of 2-（tert-butyl）-5-methylphenol and 2-（tert-butyl）-4- methylphenol binary system

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Frontiers of Chemical Science and Engineering 2013年第1期7卷 110-115页

作者： Yanhong SUN Zhiyong LI chuang xie Wei CHEN Cui ZHANG The National Engineering Research Center of Industry Crystallization Technology School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China The Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Institute of New Catalytic Materials Science College of Chemistry Nankai University Tianjin 300071 China

In this work, the enthalpy of fusion and melting points of 2-（tert-butyl）-5-methylphenol （2B5MP） and 2-（tert-butyl）-4-methylphenol （2B4MP） were measured by differential scanning calorimetry （DSC）. The binary solid-liquid equilibrium （SLE） of both compounds were predicted by integrated computer aided system （ICAS） and measured by DSC. The corresponding eutectic molar composition is 0.6998 and the eutectic temperature is 281.96 K. The quasi-static heat capacities of 2B5MP and 2B4MP were evaluated by stochastic temperature modulation DSC technique （TOPEM）. The SLE experimental data were correlated using the Margules, Wilson, and non-random two liquid （NRTL） equations and a good agreement between measurement and calculation could be obtained.

关键词： solid-liquid equilibrium (SLE) eutectic integrated computer aided system (1CAS) TOPEM correlation

The Role of Solvent in Tautomer Solvate Crystallization: A Case of 6-Amino-1,3-Dimethyl-5-Nitrosouracil

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Transactions of Tianjin University 2020年第6期26卷 458-469页

作者： Luguang Qi Yanhui Jin Huina Li Yanpeng Dong chuang xie School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Xinhua Pharmaceutical(Shouguang)Co. LtdWeifang 262700China National Collaborative Innovation Centre of Chemical Science and Engineering(Tianjin) Tianjin 300072China

Tautomers are structural isomers that readily interconvert and may exhibit diff erent *** eff ect of solvent on tautomeric equilibria in solution has been a subject of some *** solvate is less common,and the role of solvent in the crystallization of tautomer solvate remains an interesting *** this work,we used 6-amino-1,3-dimethyl-5-nitrosouracil(NAU)as the tautomeric model material,which can present in nitrone–enamine form(Tautomer A)or oxime–imine form(Tautomer B).A solvate with NAU/DMSO ratio of 1:1 was discovered and characterized using single/powder X-ray diff raction and *** crystal structure of NAU·DMSO was determined for the fi rst time,where only Tautomer A was formed in the tautomeric *** chemical calculation and molecular dynamics simulation were conducted to determine the tautomeric form in DMSO *** potential analysis,radial distribution function analysis,and binding energy suggested possible DMSO–NAU interaction modes and stable tautomer complexes in *** A-containing complexes were found to dominate in solution,as verifi ed by comparing predicted and experimental 1 H NMR *** reveal that the hydrogen bonding between DMSO and NAU is similar in solution and in NAU–DMSO solvate crystal,which helps preserve the form of Tautomer A during solvate crystallization.

关键词： Tautomerization Solvate Molecular dynamics simulation Quantum chemical calculation

Synthesis, Growth, and Characterization of a New Thiourea and Bismuth Chloride Complex with Excellent Nonlinear Optical Properties

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Transactions of Tianjin University 2018年第6期24卷 532-537页

作者： Liang Zhang Lina Zhou Baohong Hou Qiuxiang Yin chuang xie School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China National Engineering Research Center of Industrial Crystallization Technology Tianjin UniversityTianjin 300072 China National Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin 300072 China

Crystals of a new organometallic nonlinear optical （NLO） compound, di-ta-chloro-bis[chlorotri（thiourea）bismuth（Ⅲ）]- pentachloro（thiourea）bismuth-ate（Ⅲ）（DCBPB）, have been successfully grown from formic acid aqueous solutions of thio-urea and bismuth chloride by a slow evaporation technique. The crystal structure and atomic composition of DCBPB have been confirmed by single crystal X-ray diffraction （SCXRD）, Fourier transform infrared spectra, and elemental analysis. The SCXRD results proved that DCBPB crystallizes in triclinic space group P1 with unit cell dimensions of a = 7.0606（2） A, b = 8.8106（4） A, c = 16.3247（8） A, a = 99.242（4）°, fl = 95.309（3）°, ）/= 105.856（3）°, and Z= 2. DCBPB crystal exhibits excel-lent transmittance from 500 to 2500 nm and green fluorescence with maximum emission at 508 nm. The thermogravimetric-differential scanning calorimetry （TG-DSC） analysis indicates that a solid-phase reaction took place at 170.1 ℃, whereas the decomposition temperature of the crystal material was 189℃. The NLO property obtained by the Kurtz powder test showed that the second harmonic generation efficiency of DCBPB crystal is two-seventh of KDP crystal.

关键词： NLO Organometallic Thiourea Bismuth chloride TG-DTA

Control of the agglomeration of crystals in the reactive crystallization of 5-（difluoromethoxy）-2-mercapto-lH- benzimidazole

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Frontiers of Chemical Science and Engineering 2012年第4期6卷 423-431页

作者： Yongli WANG Shuyuan MA Xiaodong LU chuang xie School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

5-（Difluoromethoxy）-2-mercapto- 1H-benzimi- dazole （DMB） was precipitated by adding acetic acid to the DMB sodium salt solution. The spherical agglomeration of DMB during the reactive crystallization in a batch crystallizer was monitored by real-time Particle Video Microscope （PVM）. We found that the low feeding rate of acetic acid, high crystallization temperature, low agitation rate or adding seed crystal can facilitate the formation of spherical agglomerates. By using a simple model, the mean crystal agglomerate size of DMB thus predicted is generally in agreement with the experimental data. In addition, the crystallization process of DMB was optimized by a new control strategy of supersaturation to avoid disadvantages brought by agglomeration.

关键词： 5-(difluoromethoxy)-2-mercapto- 1H-benzi-midazole (DMB) reactive crystallization agglomeration,feeding rate crystallization temperature agitation rate

Ternary phase diagrams and solvate transformation thermodynamics of omeprazole sodium in different solvent mixtures

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Chinese Journal of Chemical Engineering 2019年第2期27卷 362-368页

作者： Meitang Jin Zhao Xu Ying Bao Long Li Liping Wang Haijiao Lu chuang xie Hongxun Hao School of Chemical Engineering and Technology Tianjin University Collaborative Innovation Centre of Chemical Science and Engineering

Omeprazole sodium(OMS), a typical non-hydrogen bond donors API, is only available in solvates so far, including monohydrate, ethanol solvate and methanol solvate. The methanol solvate was found for the first time. Solvate transformation thermodynamics of OMS was studied in this paper. First, the ternary phase diagrams forming two solvates for OMS in binary solvent mixtures including methanol + water, ethanol + water, and methanol+ ethanol were measured at temperature ranging of T =(278.15 to 313.15) K under atmospheric pressure. Further, the standard equilibrium constants of the solvate transformation reactions were evaluated according to the chemical reaction isothermal equation. The standard molar Gibbs free energy, the standard molar enthalpy, and the standard molar entropy of solvate transformation reactions were then calculated based on van't Hoff equation. Moreover, the thermodynamic stability of the OMS solvate was analyzed based on phase diagram. The results are of great importance to develop a crystallization process for manufacturing OMS solvate, and could be helpful to other solvate transformation research.

关键词： Omeprazole sodium Solvate Phase equilibria Ternary phase diagram Chemical reaction Thermodynamics

Observed response of maglev structure undercrossed by three shield tunnels in soft soil

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Underground Space 2022年第4期7卷 636-661页

作者： Dong-Mei Zhang Xiao-chuang xie Zhong-Kai Huang Mao-Zhu Peng Hong-Xin Zhu Key Laboratory of Geotechnical and Underground Engineering Ministry of EducationTongji UniversityShanghai 200092China Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Centre for Offshore Foundation Systems University of Western Australia35 Stirling HighwayCrawleyPerthWA 6009Australia Shanghai Municipal Engineering Design Institute(Group)Co. Ltd.China

This paper investigates the response of a maglev structure to three under-crossing tunnels of the Shanghai Metro Line *** minimal distance between the tunnels and pile groups of the maglev structure is only 1.5 m,thus the deformations of the maglev structure are strictly controlled for the serviceability of the operating maglev *** displacements of maglev piers and ground settlements during different tunnelling stages are monitored with an automatic measuring *** on the observed data,the ground settlement trough and displacements of maglev piers caused by the three shield tunnelling procedures are analyzed and *** maximal ground settlement after the completion of the three tunnelling procedures is -43 *** operate the existing maglev safely,practical construction control methods are applied,including synchronous grouting,adjustment of the shield status,shield-advancing speed control,and stabilisation of the soil chamber *** these countermeasures,the tunnel-induced deformations of maglev piers are well below the predefined *** piers heave under the strict deformation criterion of 2.0 *** crossing project is finally completed without interruptions of the maglev operations by monitoring the *** presented project is a valuable example for the evaluation of shield tunnelling effects on the adjacent maglev structures and establishes criteria for similar projects in the future.

关键词： Maglev Multi-crossing Shield tunnelling Ground settlement Pier displacement

A method to synthesize CdSe nanocrystals

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Frontiers of Chemical Science and Engineering 2007年第4期1卷 377-380页

作者： xie chuang CHEN Wei WANG Jingkang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

CdSe nanocrystals(NCs)have great application prospects in various fields due to their novel *** high-cost and toxic materials such as tri-n-octylphosphine oxide(TOPO)are used in the popular method to synthesize CdSe *** on this,a new low-cost,environment-friendly and safe solvent was introduced in the synthesis of CdSe NCs in this *** prepared CdSe NCs were char-acterized by ultraviolet-visible spectra(UV-Vis),photolu-minescence(PL),transmission electron micrograph(TEM),energy disperse X-ray spectra(EDX)and X-ray diffraction(XRD).The CdSe NCs obtained which show a good PL pro-perty are monodisperse,size-tunable and of high *** indicates that the new solvent A is a good substitute for the solvent used in the classic route and achieves a greener synthesis of CdSe NCs.

关键词： CdSe semiconductor NCs non-aqueous method green synthesis

Time Domain Full Waveform Inversion Based on Gradient Preconditioning with an Angle-Dependent Weighting Factor

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Journal of Ocean University of China 2022年第6期21卷 1479-1486页

作者： XIA Dongming SONG Peng LI Xishuang TAN Jun xie chuang WANG Shaowen LIU Kai ZHAO Bo MAO Shibo College of Marine Geoscience Ocean University of ChinaQingdao 266100China The Laboratory for Marine Mineral Resource Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266100China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationQingdao 266100China First Institute of Oceanography Ministry of Natural Resources(MNR)Qingdao 266061China

There are lots of low wavenumber noises in the gradients of time domain full waveform inversion(FWI),which can seriously reduce the accuracy and convergence speed of ***,we introduce an angle-dependent weighting factor to precondition the gradients so as to suppress the low wavenumber noises when the multi-scale FWI is implemented in the high *** experiments show that the FWI based on the gradient preconditioning with an angle-dependent weighting factor has faster convergence speed and higher inversion accuracy than the conventional *** tests on real marine seismic data show that this method can adapt to the FWI of field data,and provide high-precision velocity models for the actual data processing.

关键词： full waveform inversion low wavenumber noise angle-dependent weighting factor

Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： chuang xie Zhi-Liang Qin Jian-Hua Wang Peng Song Heng-Guang Shen Sheng-Qi Yu Ben-Jun Ma Xue-Qin Liu Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component