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Preparation, Characterization of Hydrotalcites and the Catalytic Properties in Synthesis of o-Phenylphenol over Pt/CHT

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Chemical Research in Chinese Universities 2005年第1期21卷 83-87页

作者： yANGPiao-ping WANGZhen-lü yUJian-feng lIUQing-sheng XUEBin ZHANGZuo-wang WUTong-hao CollegeofChemistry JilinUniversityChangchun130023P.R.China

Mg/Al mixed oxides with molar ratios of 2_6 of Mg to Al used as supports for platinum catalysts were obtained by the thermal decomposition method. The effect of the composition of the mixed oxides on the physicochemical properties was studied by TPD, nitrogen sorption, XRD and TG-DTA characterization methods. The synthesis of o-phenylphenol(OPP) from a dimer(obtained from cyclohexanone condensation) was investigated over Pt/CHT catalysts and compared with those over Pt/MgO and Pt/Al 2O 3 catalysts. These catalysts show a high activity and selectivity for OPP, with a conversion reaching 93.8% and a selectivity reaching 87.9% in some experiments. For Pt/CHTx catalysts, the calcined hydrotalcites exhibited strong base sites, which were necessary to catalyze the synthesis of OPP.

关键词： Hydrotalcite CHT OPP Dimer dehydrogenation n(Mg)/n(Al) ratio

Three-Dimensional In Situ Stress-Field Simulations of Shale Gas Formations:A Case Study of the 5th Member of the Xujiahe Formation in the Xinchang Gas Field,West Sichuan Depression

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 617-629页

作者： lüJing ZHOU Wen XIE Runcheng SHAN yuming ZHANG Chong XU hao State Key lab of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059SichuanChina

This work established a geological model for the 5th member of the Xujiahe Formation（X5 member） in the Xinchang gas field of the West Sichuan Depression based on the lithological, structural and depositional properties, as well as logging and well completion data and drill-core observations. Rock mechanical parameters were calculated according to rock mechanic experiments and rock mechanic interpretations from logging data. We also calculated the magnitudes and orientations of the in situ stresses based on acoustic emission tests, differential strain tests, fracturing behaviour and logging interpretations as well as anisotropy logging tests, borehole-breakout measurements and well-log data. Additionally, the present stress field of the X5 member was simulated using finite element numerical（FEM） simulation methods. The numerical simulation results indicate that the distributions of lithology and fractures are key factors that influence the present stress field. The stress field in the study area is discontinuous as a result of fractures and faults in the central and eastern areas. Stress is concentrated at the end sections and bends of faults, but dissipates with distance away from both sides of the faults. A longitudinal profile clearly demonstrates the zonality and continuity of the stress field and an increase with depth. The differential stress distribution is relatively uniform; however, large deviations occur in fracture zones.

关键词： in situ stress field lithology and fracture geological model West Sichuan Depression eastern margin of Tibetan Plateau Proto-Tethys

Numerical investigation of the failure mechanism of cubic concrete specimens in SHPB tests

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Defence Technology（防务技术） 2022年第1期18卷 1-11页

作者： Mei li Hong hao Jian Cui yi-fei hao labomtory of Coast Civil Structure Safety of Ministry of Education Tianjin UniversityTiarjin300072China chool of Civil Engineering.Tianin University Tianjin300072China entre for Infrastructural Monitoring and Protection School of Civil and Mechanical Engineering Curtin UniversityPerth Western Australia6845Australia

Cylindrical specimens are commonly used in Split Hopkinson pressure bar(SHPB)tests to study the uniaxial dynamic properties of concrete-like *** recent years,true tri-axial SHPB equipment has also been developed or is under development to investigate the material dynamic properties under tri-axial impact *** such tests,cubic specimens are *** is well understood that static material strength obtained from cylinder and cube specimens are *** factors are obtained and adopted in some guidelines to convert the material streng th obtained from the two types of *** uniaxial impact tests have also demonstrated that the failure mode and the strain rate effect of cubic specimens are very different from that of cylindrical ***,the mechanical background of these findings is *** an extension of the previous laboratory study,this study performs numerical SHPB tests of cubic and cylindrical concrete specimens subjected to uniaxial impact load with the validated numerical *** stress states of cubic specimens in relation to its failure mode under different strain rates is analyzed and compared with cylindrical *** detailed analyses of the numerical simulation results show that the lateral inertial confinement of the cylindrical specimen is higher than that of the cubic specimen under the same strain *** cubic specimen,the corners aremore severely damaged because of the lower lateral confinement and the occurrence of the tensile radial stress which is not observed in cylindrical *** results explain why the dynamic material strengths obtained from the two types of specimens are different and are strain rate *** on the simulation results,an empirical formula of conversion factor as a function of strain rate is proposed,which supplements the traditional conversion factor for quasi-static material *** can be used for transforming the dynamic compressive strength from

关键词： Concrete lateral inertial confinement Shape effet Dynamic failure mechanism Strain rate

Application of transparent casting moulds prepared by additive manufacturing technology in hydraulic simulation

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China Foundry 2022年第4期19卷 299-306页

作者： Qian Feng Xing Ran Ke-hui Hu hao-yuan Wang Zhi-gang lü State Key laboratory of Tribology Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China AVIC Heavy Machinery Co. Ltd.Guiyang 550005China Key laboratory of Advanced Materials Processing Technology Ministry of EducationTsinghua UniversityBeijing 100084China

Hydraulic simulation is one of the critical methods to research the filling mechanism of molten metal in the casting ***,it only performs on test pieces with relatively simple structures due to the limitation of the preparation *** this study,the method of photocuring additive manufacturing was used to prepare the complex casting mould from transparent photosensitive *** pouring test was carried out under different centrifugal conditions,and the filling process of the gating system,support bars and other positions in the vertical direction was recorded and *** experimental results show that the internal liquid level and the filling process of the test piece prepared by this method can be observed *** angle between the liquid surface and the horizontal plane in the test piece gradually increases as the centrifugal rotational speed increases,which means the filling process is carried out from outside to inside at high rotational *** velocity of the fluid entering the runner increases with the increase of rotational speed,but the filling speeds is less affected by the centrifugal speed at other *** liquid flow is continuous and stable during the forward filling process,without splashing or interruption of liquid droplets.

关键词： additive manufacturing centrifugal casting investment casting hydraulic simulation transparent mould

Effect of CO_(2) Opposing Multiple Jets on Thermoacoustic Instability and NO_(x) Emissions in a lean-Premixed Model Combustor

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Journal of Thermal Science 2024年第1期33卷 207-221页

作者： ZHOU hao HU liubin Institute for Thermal Power Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou 310027China

This paper experimentally studied the effect of CO_(2) opposing multiple jets on the thermoacoustic instability and NO_(x) emissions in a lean-premixed model *** feasibility was verified from three variables:the CO_(2) jet flow rate,hole numbers,and hole diameters of the *** indicate that the control effect of thermoacoustic instability and NO_x emissions show a reverse trend with the increase of open area ratio on the whole,and the optimal jet flow rate range is 1-4 l/min with CO_(2) opposing multiple *** this flow rate range,the amplitude and frequency of the dynamic pressure and heat release signals CH~* basically decrease as the CO_(2) flow rate increases,which avoids high-frequency and high-amplitude thermoacoustic *** amplitude-damped ratio of dynamic pressure and CH*can reach as high as 98.75% and 93.64% with an optimal open area ratio of 3.72%.NO_(x) emissions also decrease as the jet flow rate increases,and the maximum suppression ratio can reach 68.14%.Besides,the flame shape changes from a steep inverted "V" to a more flat "M",and the flame length will become shorter with CO_(2) opposing multiple *** research achieved the synchronous control of thermoacoustic instability and NO_(x) emissions,which could be a design reference for constructing a safer and cleaner combustor.

关键词： thermoacoustic instability lean-premixed model combustor CO_(2)opposing multiple jets open area ratio NO_(x)emissions

Polysulfone Membranes via Thermally Induced Phase Separation

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Chinese Journal of Polymer Science 2017年第7期35卷 846-856页

作者： Hong-qing liang hao-nan li hao-hao yu yong-ting Zhou 徐志康 Key laboratory of Macromolecular Synthesis and Functionalization of the Ministry of Education Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China Key laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Polysulfone （PSF） membranes have gained great attention in the fields of ultrafiltration, microfiltration, and thin film composite membranes for nanofiltration or reverse osmosis. For the first time, it is proposed to fabricate PSF membranes via thermally induced phase separation （TIPS） process using diphenyl sulfone （DPSO2） and polyethylene glycol （PEG） as mixed diluent. DPSO2 is chosen as a crystallizable diluent, while PEG is considered in terms of molecular weight （Mw） and dosage. We systematically investigate the interactions between PSF, DPSO2 and PEG based on the simulation calculations and solubility parameter theory. It is inferred that DPSO2 has an excellent compatibility with PSF, and the addition of PEG results in the ternary system thermodynamically less stable and then facilitates its liquid-liquid （l-l） phase separation. SEM images indicate that cellular-like pores are obvious throughout the membrane when the PEG content in the mixed diluent is 25 wt%-35 wt%. We can facilely manipulate the pore size, water flux and mechanical properties of PSF membranes with the dosage of PEG-200, the Mw of PEG or the cooling rate. The successful application of TIPS can provide a new approach for structure manipulation and performance enhancement of PSF membranes.

关键词： Polysulfone membrane Pore structure Diphenyl sulfone Polyethylene glycol Thermally inducedphase separation

Characterization of nitrogen-containing aromatics in Baiyinhua lignite and its soluble portions from thermal dissolution

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Chinese Journal of Chemical Engineering 2019年第11期27卷 2783-2787页

作者： yangyang Zhang Xianyong Wei Jinghui lü hao Jiang Fangjing liu Guanghui liu Zhimin Zong Key laboratory of Coal Processing and Efficient Utilization Ministry of EducationChina University of Mining&TechnologyXuzhou 221116China State Key laboratory of High-efficiency Utilization and Green Chemical Engineering Ningxia UniversityYinchuan 750021China Department of Chemical Engineering College of Chemical EngineeringHenan Polytechnic UniversityJiaozuo 454003China

Soluble portions(SPs) 1-4(SP1-SP4) were afforded from sequentially dissolution and alkanolyses of Baiyinhua lignite(Bl) in cyclohexane,CH3OH,CH3CH2OH,and(CH3)2CHOH at 300℃.They were analyzed with a gas chromatograph/mass spectrometer and quadrupole exactive orbitrap mass spectrometer(QEOTMS) with an atmosphere pressure chemical ionization source in positive-ion mode,while Bl was characterized with an X-ray photoelectron spectrometer(XRPES).The results show that the yields of SP2 and SP3 are much higher than those of SP1 and SP4,and the total SP yield is ca.39.0%.According to the analysis with XRPES,pyrrolic nitrogen atoms are the most abundant nitrogen existing forms in *** of nitrogen-containing aromatics(NCAs) were resolved with QEOTMS and their molecular masses are mainly in the range of 200-450 *** main NCAs are N1O1 and N1O2 class species with double bond equivalent values of 4-18 and carbon numbers of *** nitrogen atoms appear in pyridine s,quinolines,benzoquinolines or acridine,and dibenzoquinolines or naphthoquinolines,while the oxygen atoms exist in methoxy and furan rings.

关键词： lignite Sequential thermal dissolution and alkanolyses Nitrogen-containing aromatics

Electrode particulate materials for advanced rechargeable batteries:A review

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Particuology 2024年第3期86卷 160-181页

作者： Mingyang Ma Miao Du yan liu Hongyan lü Jialin yang Zelin hao Jinzhi Guo Xinglong Wu MOE Key laboratory for UV light-Emitting Materials and Technology Northeast Normal UniversityChangchunJilin130024China Department of Chemistry Northeast Normal UniversityChangchunJilin130024China

The demand for large-scale energy storage is increasing due to the decreasing non-renewable resources and deteriorating environmental *** rechargeable batteries with high energy density and long cycle performance is an ideal choice to meet the demand of energy storage *** development of excellent electrode particles is of great significance in the commercialization of nextgeneration *** ideal electrode particles should balance raw material reserves,electrochemical performance,price and environmental *** them,the development of electrode particulate materials with excellent electrochemical properties is the top priority at *** this review,the typical researches of electrode materials are summarized in terms of crystal structure,morphology,pore structure,surface and interface ***,the structural characteristics and improvement methods of transition metal oxides,polyanionic compounds,Prussian blue and their analogues are ***,the different effects of particulate morphology,pore,surface and interface structure on the performance of electrode materials are *** designing high-performance electrode materials,preparation route should be set according to the particle properties of the materials and the synergistic effect of various optimization methods should be *** the same time,in addition to the electrode materials,other components of the rechargeable batteries,such as current collector,separator and electrolytes,should be optimized to improve the overall performance of the *** review would provide important guiding principle for designing high-performance electrode particulate materials.

关键词： Particulate properties Electrode materials Rechargeable batteries

Cracking the Codes of Cortical Glial Progenitors:Evidence for the Common lineage of Astrocytes and Oligodendrocytes

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Neuroscience Bulletin 2021年第4期37卷 437-439页

作者： hao Huang John lRubenstein Mengsheng Qiu Nina Ireland laboratory of Developmental Neurobiology Department of Psychiatry and Behavioral SciencesUniversity of CaliforniaSan FranciscoCA94158USA Institute of life Sciences College of Life and Environmental SciencesCollege of Basic Medical ScienceHangzhou Normal UniversityHangzhou311121China

During the development of the central nervous system(CNS),neuroepithelial cells in the ventricular zone are multipotent stem cells that can generate neurons and macroglia(astrocytes or oligodendrocytes).It is generall... 详细信息

关键词： cytes ventricular progenitor