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Synthesis of methanol and ethanol over CuZnAl slurry catalyst prepared by complete liquid-phase technology

Wei HUANG, Linmei YU, Wenhui LI, Zhili MA

《化学科学与工程前沿（英文）》 2010年 第4卷 第4期   页码 472-475 doi: 10.1007/s11705-010-0525-6

摘要： A new method, named the complete liquid-phase technology, has been applied to prepare catalysts for methanol synthesis. Its main innovative thought lies in preparing slurry catalysts directly from raw solution. Activity tests indicate that the CuZnAl slurry catalyst prepared by the new method can efficiently catalyze conversion of syngas to ethanol in a slurry reactor, while CO conversion reaches 35.9% and ethanol selectivity is more than 20%, with a total alcohol selectivity of more than 87%. No deactivation was found during the 192 h reaction .

关键词： methanol     slurry     ethanol     complete liquid-phase technology     CuZnAl catalyst    

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Advances and perspectives in catalysts for liquid-phase oxidation of cyclohexane

Hui LI, Yuanbin SHE, Tao WANG

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 356-368 doi: 10.1007/s11705-012-0903-3

摘要： The latest progress and developments in catalysts for the oxidation of cyclohexane are reviewed. Catalytic systems for the oxidation of cyclohexane including metal supported, metal oxides, molecular sieves, metal substituted polyoxometalates, photocatalysts, organocatalysts, Gif systems, metal-organic catalysts and metalloporphyrins are discussed with a particular emphasis on metalloporphyrin catalytic systems. The advantages and disadvantages of these methods are summarized and analyzed. Finally, the development trends in the oxidation technology of cyclohexane are examined.

关键词： cyclohexane     liquid-phase oxidation     catalysis    

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Reconstruction of Cu–ZnO catalyst by organic acid and deactivation mechanism in liquid-phase hydrogenation

《化学科学与工程前沿（英文）》 2023年 第17卷 第9期   页码 1311-1319 doi: 10.1007/s11705-022-2281-9

摘要： A reconstructed Cu–ZnO catalyst with improved stability was fabricated by organic acid treatment method for the liquid-phase hydrogenation of dimethyl succinate to 1,4-butanediol. According to the characterization results of the fresh Cu–ZnO and reconstructed Cu–ZnO, three different forms of ZnO were suggested to be presented on the catalysts: ZnO having strong interaction with Cu species, ZnO that weakly interacted with Cu species and isolated ZnO. The first form of ZnO was believed to be beneficial to the formation of efficient active site Cu+, while the latter two forms of ZnO took the main responsibility for the deactivation of Cu–ZnO catalysts in the liquid-phase hydrogenation of diesters. The reconstruction of the Cu–ZnO catalyst by the organic acid treatment method resulted in a new Cu–ZnO catalyst with more Cu+ and less ZnO species that leads to deactivation. Furthermore, the deactivation mechanism of Cu–ZnO catalysts in liquid-phase diester hydrogenation in continuous flow system was proposed: the deposition of the polyesters on the catalysts via transesterification catalyzed by weakly interacted ZnO and isolated ZnO leads to the deactivation. These results provided meaningful instructions for designing highly efficient Cu–Zn catalysts for similar ester hydrogenation systems.

关键词： liquid phase     hydrogenation     Cu–ZnO     deactivation mechanism     1     4-butanediol     diester    

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Metal salts with highly electronegative cations as efficient catalysts for the liquid-phase nitration

Shenghui Zhou, Kuiyi You, Zhengming Yi, Pingle Liu, Hean Luo

《化学科学与工程前沿（英文）》 2017年 第11卷 第2期   页码 205-210 doi: 10.1007/s11705-017-1625-3

摘要： Metal salts with highly electronegative cations have been used to effectively catalyze the liquid-phase nitration of benzene by NO to nitrobenzene under solvent-free conditions. Several salts including FeCl , ZrCl , AlCl , CuCl , NiCl , ZnCl , MnCl , Fe(NO ) ·9H O, Bi(NO ) ·5H O, Zr(NO ) ·5H O, Cu(NO ) ·6H O, Ni(NO ) ·6H O, Zn(NO ) ·6H O, Fe (SO ) , and CuSO were examined and anhydrous FeCl exhibited the best catalytic performance under the optimal reaction conditions. The benzene conversion and selectivity to nitrobenzene were both over 99%. In addition, it was determined that the metal counterion and the presence of water hydrates in the salt affects the catalytic activity. This method is simple and efficient and may have potential industrial application prospects.

关键词： metal salts     electronegativity     nitrobenzene     NO2     catalytic nitration    

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利用液相透射电子显微镜技术研究纳米气泡在表面活性剂水溶液中的动力机制 Letter

Yuna Bae, Sungsu Kang, Byung Hyo Kim, Kitaek Lim, Sungho Jeon, Sangdeok Shim, Won Chul Lee, Jungwon Park

《工程（英文）》 2021年 第7卷 第5期   页码 630-635 doi: 10.1016/j.eng.2021.02.006

摘要：

纳米气泡因其超长的寿命和作为纳米级载体的潜力而在各种工业应用中受到广泛关注。纳米气泡的稳定性和理化性质对表面活性剂的存在高度敏感，表面活性剂可降低其表面张力或提高其静电稳定性。在本文中，我们报道了在存在可溶性表面活性剂的条件下纳米气泡动态行为的实时观察结果。利用多室石墨烯液体池液相透射电子显微镜（TEM），在相同的成像条件下观察了体相纳米气泡和表面纳米气泡。对纳米气泡的直接观察结果表明，稳定的气体传输在没有界面融合的情况下经常发生，而在相互作用的含表面活性剂的纳米气泡界面之间存在狭窄的距离。结果也阐明了纳米气泡的界面曲率是决定其界面稳定性的重要因素。

关键词： 纳米气泡     原位透射电镜     液相透射电镜     表面活性剂    

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Microfluidic production of liposomes through liquid–liquid phase separation in ternary droplets

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 1017-1022 doi: 10.1007/s11705-021-2118-y

摘要： Liposomes, the self-assembled phospholipid vesicles, have been extensively used in various fields such as artificial cells, drug delivery systems, biosensors and cosmetics. However, current microfluidic routes to liposomes mostly rely on water-in-oil-in-water double emulsion droplets as templates, and require complex fabrication of microfluidic devices, and tedious manipulation of multiphase fluids. Here we present a simple microfluidic approach to preparing monodisperse liposomes from oil-in-water droplets. For demonstration, we used butyl acetate-water-ethanol ternary mixtures as inner phase and an aqueous solution of surfactants as outer phase to make oil-in-water droplets, which can evolve into water-in-oil-in-water double emulsion droplets by liquid–liquid phase separation of ternary mixtures. Subsequently, the resultant water-in-oil-in-water droplets underwent a dewetting transition to form separated monodisperse liposomes and residual oil droplets, with the assistance of surfactants. The method is simple, does not require complex microfluidic devices and tedious manipulation, and provides a new platform for controllable preparation of liposomes.

关键词： microfluidics     liposomes     ternary droplets     phase separation    

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Analysis of the radiation heat transfer process of phase change for a liquid droplet radiator in space

Jinying YIN, Linhua LIU

《能源前沿（英文）》 2011年 第5卷 第2期   页码 166-173 doi: 10.1007/s11708-010-0105-y

摘要： The optimization of a space power system is greatly affected by the radiation heat transfer in a liquid droplet radiator (LDR). Radiation heat transfer in a two-dimensional bed of phase-change particle is modeled by solving the radiative transfer equation using the discrete ordinates method and the energy equation using the implicit finite difference method. The Mie theory is used to calculate the radiative properties of the droplet bed, whereas the effective medium theory is used to obtain the optical constants of partial solidification droplets. Multiple factors affect heat flux in the LDR, such as size distribution, flow velocity, phase change of droplets, layer thickness, droplet concentration in the layer, and material type of the work fluid; each of these must be analyzed. Calculations show that once size distribution is neglected, the relative error increases significantly. Size distribution has a remarkably strong effect on heat flux when the flow velocity of the working fluid is above 100 m/s. An increase in flow velocity leads to an increase in the total heat flux for the layer with a fixed volume fraction of droplets. The solidification zone occupies nearly half of the layer, and droplets of different sizes exhibit temperature differences to some extent due to local thermal non-equilibrium among them. Droplet concentration in the layer and the material type of the working fluid have strong effects on heat flux, whereas the thickness of the layer has a mild influence on heat flux.

关键词： radiation heat transfer     particle polydispersion     liquid droplet radiator     phase change    

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Shock wave of vapor-liquid two-phase flow

ZHAO Liangju, GAO Hong, TANG Jingwen, YUAN Yuexiang, WANG Fei

《能源前沿（英文）》 2008年 第2卷 第3期   页码 344-347 doi: 10.1007/s11708-008-0065-7

摘要： The shock wave of vapor-liquid two-phase flow in a pressure-gain steam injector is studied by building a mathematic model and making calculations. The results show that after the shock, the vapor is nearly completely condensed. The upstream Mach number and the volume ratio of vapor have a great effect on the shock. The pressure and Mach number of two-phase shock conform to the shock of ideal gas. The analysis of available energy shows that the shock is an irreversible process with entropy increase.

关键词： available     mathematic     conform     vapor-liquid two-phase     analysis    

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Residence time distribution and modeling of the liquid phase in an impinging stream reactor

Xingjun WANG, Xianhui HU, Lishun HU, Guangsuo YU, Fuchen WANG,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 353-359 doi: 10.1007/s11705-009-0262-x

摘要： Based on some experimental investigations of liquid phase residence time distribution (RTD) in an impinging stream reactor, a two-dimensional plug-flow dispersion model for predicting the liquid phase RTD in the reactor was proposed. The calculation results of the model can be in good agreement with the experimental RTD under different operating conditions. The axial liquid dispersion coefficient increases monotonously with the increasing liquid flux, but is almost independent of gas flux. As the liquid flux and the gas flux increase, the liquid dispersion coefficient of center-to-wall decreases. The axial liquid dispersion coefficient is much larger than that of center-to-wall, which indicates that the liquid RTD is dominated mainly by axial liquid dispersion in the impinging stream reactor.

关键词： RTD     liquid dispersion     reactor     liquid     independent    

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SiO2 passivation layer grown by liquid phase deposition for silicon solar cell application

Yanlin CHEN,Sihua ZHONG,Miao TAN,Wenzhong SHEN

《能源前沿（英文）》 2017年 第11卷 第1期   页码 52-59 doi: 10.1007/s11708-016-0429-3

摘要： Surface passivation is one of the primary requirements for high efficient silicon solar cells. Though the current existed passivation techniques are effective, expensive equipments are required. In this paper, a comprehensive understanding of the SiO passivation layer grown by liquid phase deposition (LPD) was presented, which was cost-effective and very simple. It was found that the post-annealing process could significantly enhance the passivation effect of the LPD SiO film. Besides, it was revealed that both chemical passivation and field-effect passivation mechanisms played important roles in outstanding passivation effect of the LPD SiO film through analyzing the minority carrier lifetime and the surface recombination velocity of n-type and p-type silicon wafers. Although the deposition parameters had little influence on the passivation effect, they affected the deposition rate. Therefore, appropriate deposition parameters should be carefully chosen based on the compromise of the deposition rate and fabrication cost. By utilizing the LPD SiO film as surface passivation layer, a 19.5%-efficient silicon solar cell on a large-scale wafer (156 mm × 156 mm) was fabricated.

关键词： Si solar cell     passivation     SiO2     liquid phase deposition     carrier lifetime    

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Numerical simulation of three-dimensional gas/liquid two-phase flow in a proton exchange membrane fuel

ZHUGE Weilin, ZHANG Yangjun, LAO Xingsheng, CHEN Xiao, MING Pingwen

《能源前沿（英文）》 2007年 第1卷 第3期   页码 305-310 doi: 10.1007/s11708-007-0044-4

摘要： Investigation into the formation and transport of liquid water in proton exchange membrane fuel cells (PEMFCs) is the key to fuel cell water management. A three-dimensional gas/liquid two-phase flow and heat transfer model is developed based on the multiphase mixture theory. The reactant gas flow, diffusion, and chemical reaction as well as the liquid water transport and phase change process are modeled. Numerical simulations on liquid water distribution and its effects on the performance of a PEMFC are conducted. Results show that liquid water distributes mostly in the cathode, and predicted cell performance decreases quickly at high current density due to the obstruction of liquid water to oxygen diffusion. The simulation results agree well with experimental data.

关键词： diffusion     gas/liquid two-phase     management     exchange     transfer    

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Effect of counter current gas phase on liquid film

Shujuan LUO, Huaizhi LI, Weiyang FEI, Yundong WANG

《化学科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 135-137 doi: 10.1007/s11705-009-0129-1

摘要： Liquid film flow is very important in many industrial applications. However, there are few reports about its characteristics on structured packings. Therefore, in this paper, liquid film phenomena were investigated experimentally to exploit new approaches for intensifying the performance of the structured packings. All experiments were performed at room temperature. Water and air were the working fluids. The effect of counter current gas phase on the liquid film was taken into consideration. A high speed camera, a non-intrusive measurement technique, was used. It is shown that both liquid and gas phases have strong effects on film characteristics. In the present work, liquid film width increased by 57% because of increasing liquid flow rate, while it decreased by 25% resulting from the counter current gas phase.

关键词： counter current     liquid film     two phases     structured packings    

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Development of new transient liquid phase system Au-Sn-Au for microsystem technology

Kirsten BOBZIN, Nazlim BAGCIVAN, Lidong ZHAO, Stefania FERRARA, Jan PERNE

《机械工程前沿（英文）》 2010年 第5卷 第4期   页码 370-375 doi: 10.1007/s11465-010-0107-9

摘要： In the last decade, microsystems evolved to decisive technology in many technical applications. With increasing requirements on the performance of microsystems, more and more dissimilar materials are used in the same assembly. Correspondingly, suitable joining methods are required to fulfil the requirements on good properties of joints. In this study, a new transient liquid phase (TLP) system Au-Sn-Au was developed for potential medical applications in hybrid microsystems. The high and low melting phases Au and Sn were deposited onto diverse substrates by magnetron-sputter-ion plating. The coated substrates were soldered in a microsoldering station under different conditions. The influence of soldering conditions on the microstructure and properties of the joints was investigated. Results show that the developed solder led to high-quality joints that can be used in microsystems for medical applications.

关键词： transient liquid phase     microtechnology     soldering     diffusion     physical vapor deposition (PVD)    

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Energy distribution between liquid hydrogen and liquid oxygen temperatures in a Stirling/pulse tube refrigerator

《能源前沿（英文）》 2023年 第17卷 第4期   页码 516-526 doi: 10.1007/s11708-022-0844-6

摘要： A two-stage gas-coupled Stirling/pulse tube refrigerator (SPR), whose first and second stages respectively involve Stirling and pulse tube refrigeration cycles, is a very promising spaceborne refrigerator. The SPR has many advantages, such as a compact structure, high reliability, and high performance, and is expected to become an essential refrigerator for space applications. In research regarding gas-coupled regenerative refrigerator, the energy flow distribution between the two stages, and optimal phase difference between the pressure wave and volume flow, are two critical parameters that could widely influence refrigerator performance. The effects of displacer displacement on the pressure wave, phase difference, acoustic power distribution, and inter-stage cooling capacity shift of the SPR have been investigated experimentally. Notably, to obtain the maximum first-stage cooling capacity, an inflection point in displacement exists. When the displacer displacement is larger than the inflection point, the cooling capacity could be distributed between the first and second stages. In the present study, an SPR was designed and manufactured to work between the liquid hydrogen and liquid oxygen temperatures, which can be used to cool small-scale zero boil-off systems and space detectors. Under appropriate displacer displacement, the SPR can reach a no-load cooling temperature of 15.4 K and obtain 2.6 W cooling capacity at 70 K plus 0.1 W cooling capacity at 20 K with 160 W compressor input electric power.

关键词： Stirling/pulse tube refrigerator     displacer displacement     space application     phase shift     energy distribution    

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Thermodynamic analysis of liquid phase in situ hydrogenation of glycerol for 1,3-propanediol synthesis

Kun OUYANG, Yu HUANG, Haoyi CHEN, Tao LI, Fahai CAO, Dingye FANG

《化学科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 67-73 doi: 10.1007/s11705-010-0541-6

摘要： Based on the combination of the glycerol aqueous-phase reforming (APR) and catalytic hydrogenation of glycerol, a novel reaction system of liquid phase in situ hydrogenation of glycerol for the synthesis of 1,3-propanediol is proposed, in which hydrogen is produced from glycerol aqueous-phase reforming in the same reactor. In this new system, the glycerol is the raw material of the aqueous-phase reforming reaction; the hydrogen generated from the APR of glycerol can be quickly transformed to the in situ hydrogenation of glycerol to produce 1,3-propanediol, which can improve the selectivity of hydrogen for the APR process of glycerol. Moreover, thermodynamic calculation of the coupling processes was carried out, and standard molar enthalpies and equilibrium constants of foregoing reactions were obtained. The above calculation results indicate that the combination process is feasible for 1,3-propanediol synthesis.

关键词： glycerol     aqueous-phase reforming     1     3-propanediol     in-situ reduction    

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标题 作者 时间 类型 操作

Synthesis of methanol and ethanol over CuZnAl slurry catalyst prepared by complete liquid-phase technology

Wei HUANG, Linmei YU, Wenhui LI, Zhili MA

期刊论文

Advances and perspectives in catalysts for liquid-phase oxidation of cyclohexane

Hui LI, Yuanbin SHE, Tao WANG

期刊论文

Reconstruction of Cu–ZnO catalyst by organic acid and deactivation mechanism in liquid-phase hydrogenation

期刊论文

Metal salts with highly electronegative cations as efficient catalysts for the liquid-phase nitration

Shenghui Zhou, Kuiyi You, Zhengming Yi, Pingle Liu, Hean Luo

期刊论文

利用液相透射电子显微镜技术研究纳米气泡在表面活性剂水溶液中的动力机制

Yuna Bae, Sungsu Kang, Byung Hyo Kim, Kitaek Lim, Sungho Jeon, Sangdeok Shim, Won Chul Lee, Jungwon Park

期刊论文

Microfluidic production of liposomes through liquid–liquid phase separation in ternary droplets

期刊论文

Analysis of the radiation heat transfer process of phase change for a liquid droplet radiator in space

Jinying YIN, Linhua LIU

期刊论文

Shock wave of vapor-liquid two-phase flow

ZHAO Liangju, GAO Hong, TANG Jingwen, YUAN Yuexiang, WANG Fei

期刊论文

Residence time distribution and modeling of the liquid phase in an impinging stream reactor

Xingjun WANG, Xianhui HU, Lishun HU, Guangsuo YU, Fuchen WANG,

期刊论文

SiO2 passivation layer grown by liquid phase deposition for silicon solar cell application

Yanlin CHEN,Sihua ZHONG,Miao TAN,Wenzhong SHEN

期刊论文

Numerical simulation of three-dimensional gas/liquid two-phase flow in a proton exchange membrane fuel

ZHUGE Weilin, ZHANG Yangjun, LAO Xingsheng, CHEN Xiao, MING Pingwen

期刊论文

Effect of counter current gas phase on liquid film

Shujuan LUO, Huaizhi LI, Weiyang FEI, Yundong WANG

期刊论文

Development of new transient liquid phase system Au-Sn-Au for microsystem technology

Kirsten BOBZIN, Nazlim BAGCIVAN, Lidong ZHAO, Stefania FERRARA, Jan PERNE

期刊论文

Energy distribution between liquid hydrogen and liquid oxygen temperatures in a Stirling/pulse tube refrigerator

期刊论文

Thermodynamic analysis of liquid phase in situ hydrogenation of glycerol for 1,3-propanediol synthesis

Kun OUYANG, Yu HUANG, Haoyi CHEN, Tao LI, Fahai CAO, Dingye FANG

期刊论文