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Vaporization behavior of lead from the FeO-CaO-SiO_2-Al_2O_3 slag system 被引量:3
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作者 Yanling Zhang Rui Zhang +1 位作者 Eiki Kasai Shiqi Li 《Journal of University of Science and Technology Beijing》 CSCD 2008年第6期671-677,共7页
Vaporization behavior (1163-1463 K) of lead in the slag system of FeO-CaO-SiO2-Al2O3 with CaC% was examined. A thermodynamic estimation with the principle of Gibbs free energy minimization showed that the major vapo... Vaporization behavior (1163-1463 K) of lead in the slag system of FeO-CaO-SiO2-Al2O3 with CaC% was examined. A thermodynamic estimation with the principle of Gibbs free energy minimization showed that the major vapor species from the sample of the FeO-CaO-SiO2-Al2O3 system+PbO+CaCl2 were metallic Pb, PbCl, PbCl2, and FeCl2, at the experimental temperature range. The experimental results show that the mole ratio of vaporized Cl in lead chlorides to vaporized Pb, simply expressed as Cl/Pb decreases with increasing temperature. The larger Cl/Pb means a larger ratio of gaseous PbCl2, since metallic Pb and PbCl vapors are formed in a similar reduction atmosphere. The evaporation is initially rapid and becomes steady after holding for 10 min. Gaseous PbCl2 is mainly formed during the heating period, and at the holding stage, it reacts with FeO to produce gaseous FeCl2 With regard to slag composition, FeO content and basicity significantly affect the evaporation of lead. High FeO content and high basicity promotes the formation of metallic Pb and PbCI, whereas, it prohibits PbCl2 evaporation. 展开更多
关键词 slag system smelting process vaporization behavior LEAD
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Determination of Cd,Pb and Sr by Microwave Plasma Torch Atomic Emision Spectrometry Using an Electrothermal Vaporization Sample Introduction System
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作者 ZHAO Li-wei ZHANG Han-qí +4 位作者 CAO Yan-bo YANG Wen-jun JIN Qun JIN Qin-han FU Yao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第4期22-26,共5页
IntroductionEletrothermalvaporization(ETV)asameansofsampleintroductioninmicrowavein-ducedplasma(MIP)sourcesp... IntroductionEletrothermalvaporization(ETV)asameansofsampleintroductioninmicrowavein-ducedplasma(MIP)sourcespectrometryhasbeen... 展开更多
关键词 Atomic emission spectrometry Microwave plasma torch Electrothermal vaporization
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Experimental Investigation on Condensate Revaporization During Gas Injection Development in Fractured Gas Condensate Reservoirs
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作者 Lei Zhang Yingxu He +3 位作者 Jintao Wu Haojun Wu Lei Huang Linna Sun 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第3期575-582,共8页
The gas field in the Bohai Bay Basin is a fractured metamorphic buried-hill reservoir with dual-media characteristics. The retrograde vaporization mechanism observed in this type of gas condensate reservoir differs si... The gas field in the Bohai Bay Basin is a fractured metamorphic buried-hill reservoir with dual-media characteristics. The retrograde vaporization mechanism observed in this type of gas condensate reservoir differs significantly from that observed in sand gas condensate reservoirs. However, studies on improving the recovery of fractured gas condensate reservoirs are limited;thus, the impact of retrograde vaporization on condensate within fractured metamorphic buried-hill reservoirs remains unclear. To address this gap, a series of gas injection experiments are conducted in pressure-volume-temperature(PVT) cells and long-cores to investigate the retrograde vaporization effect of condensate using different gas injection media in fractured gas condensate reservoirs. We analyze the variation in condensate volume, gas-to-oil ratio, and condensate recovery during gas injection and examine the influence of various gas injection media(CO_(2), N_(2), and dry gas) under different reservoir properties and varying gas injection times. The results demonstrate that the exchange of components between injected gas and condensate significantly influences condensate retrograde vaporization in the formation. Compared with dry gas injection and N_(2) injection,CO_(2) injection exhibits a superior retrograde vaporization effect. At a CO_(2) injection volume of 1 PV, the percentage shrinkage volume of condensate is 13.82%. Additionally, at the maximum retrograde condensation pressure, CO_(2) injection can increase the recovery of condensate by 22.4%. However, the condensate recovery is notably lower in fractured gas condensate reservoirs than in homogeneous reservoirs, owing to the creation of dominant gas channeling by fractures, which leads to decreased condensate recovery. Regarding gas injection timing, the effect of gas injection at reservoir pressure on improving condensate recovery is superior to that of gas injection at the maximum retrograde condensation pressure. This research provides valuable guidance for designing gas injection development plans and dynamic tracking adjustments for fractured gas condensate reservoirs. 展开更多
关键词 Buried-hill fractured reservoir Gas condensate reservoir Retrograde condensation CO_(2)injection Retrograde vaporization
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Exergy Analysis of a Solar Vapor Compression Refrigeration System Using R1234ze(E)as an Environmentally Friendly Replacement of R134a
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作者 Zakaria Triki Ahmed Selloum +6 位作者 Younes Chiba Hichem Tahraoui Dorsaf Mansour Abdeltif Amrane Meriem Zamouche Mohammed Kebir Jie Zhang 《Frontiers in Heat and Mass Transfer》 EI 2024年第4期1107-1128,共22页
Refrigeration plays a significant role across various aspects of human life and consumes substantial amounts of electrical energy.The rapid advancement of green cooling technology presents numerous solar-powered refri... Refrigeration plays a significant role across various aspects of human life and consumes substantial amounts of electrical energy.The rapid advancement of green cooling technology presents numerous solar-powered refrigeration systems as viable alternatives to traditional refrigeration equipment.Exergy analysis is a key in identifying actual thermodynamic losses and improving the environmental and economic efficiency of refrigeration systems.In this study exergy analyze has been conducted for a solar-powered vapor compression refrigeration(SP-VCR)system in the region of Gharda颽(Southern Algeria)utilizing R1234ze(E)fluid as an eco-friendly substitute for R134a refrigerant.A MATLAB-based numerical model was developed to evaluate losses in different system components and the exergy efficiency of the SP-VCR system.Furthermore,a parametric study was carriedout to analyze the impact of various operating conditions on the system’s exergy destruction and efficiency.The obtained results revealed that,for both refrigerants,the compressor exhibited the highest exergy destruction,followed by the condenser,expansion valve,and evaporator.However,the system using R1234ze(E)demonstrated lower irreversibility compared to that using R134a refrigerant.The improvements made with R1234ze are 71.95%for the compressor,39.13%for the condenser,15.38%for the expansion valve,5%for the evaporator,and 54.76%for the overall system,which confirm the potential of R1234ze(E)as a promising alternative to R134a for cooling applications. 展开更多
关键词 Solar cooling vapor compression refrigeration eco-friendly refrigerant thermodynamic losses exergy analysis
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Determination of Latent Heats of Vaporization and Fusion
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作者 Lahbib Abbas Lahcen Bih +3 位作者 Khalid Yamni Abderrahim Elyahyaouy Abdelmalik El Attaoui Zahra Ramzi 《Advances in Chemical Engineering and Science》 CAS 2024年第3期113-124,共12页
Water is the most abundant liquid on the surface of the earth. It is a liquid whose properties are quite surprising, both as a pure liquid and as a solvent. Water is a very cohesive liquid: its melting and vaporizatio... Water is the most abundant liquid on the surface of the earth. It is a liquid whose properties are quite surprising, both as a pure liquid and as a solvent. Water is a very cohesive liquid: its melting and vaporization temperatures are very high for a liquid that is neither ionic nor metallic, and whose molar mass is low. Thus, water remains liquid at atmospheric pressure up to 100C while similar molecules such as H2S, H2Se, H2Te for example would give a vaporization temperature close to 80C. This cohesion is in fact ensured by hydrogen bonds between water molecules. This type of bonds between neighboring molecules, hydrogen bonds, is quite often found in chemistry [1] [2]. Any change in the state of aggregation of a substance occurs with the absorption or release of a certain amount of latent heat of transformation. Latent heat of fusion, vaporization or sublimation is the ratio of the energy supplied as heat to the mass of the substance that is melted, vaporized or sublimated. As a result of the reversibility of the processes, the fusion heat is equal to the heat released in the reverse process: crystallization and solidification heat. And likewise the heat of vaporization is equal to the heat of condensation. This equality of heat is often used to determine experimentally either of these quantities. There are two main measurement methods: 1) Direct measurement using the calorimeter, 2) Indirect measure based on the use of the VantHoff relationship. The objective of this work is to measure the latent heat of water vaporization and verify the compatibility of the experimental values with the values given by the tables using the indirect method. 展开更多
关键词 Latent Heat of vaporization Latent Heat of Fusion CALORIMETRY Relationship of Vant’Hoff
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Vapor pressure measurement of lead and lead chlorides in FeO_T-CaO-SiO_2-Al_2O_3 system 被引量:1
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作者 张延玲 Eiki KASAI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2772-2780,共9页
Vapor pressure of lead and lead chlorides from FeOT?CaO?SiO2?Al2O3 slag system was measured by using Knudsen effusion method. The results suggest that the vapor pressures of lead and lead chlorides increase with in... Vapor pressure of lead and lead chlorides from FeOT?CaO?SiO2?Al2O3 slag system was measured by using Knudsen effusion method. The results suggest that the vapor pressures of lead and lead chlorides increase with increasing temperature. For the slag systems without chlorine, the logarithm of vapor pressure (lnp) shows highly linear dependency on the reciprocal of temperature (1/T), and higher vapor pressure is observed in the condition where more metallic lead vapor is formed. In this case, the vapor pressure of lead increases with increasing slag basicity (w(CaO)/w(SiO2)), increasing FeO content andw(Fe2+)/w(Fe3+) ratio. For the case of slag system with chlorine addition, the total pressures of PbCl2 and PbCl increase with decreasing basicity and FeO content of slag. 展开更多
关键词 金属Pb vapor pressure Knudsen effusion method metallic Pb lead chlorides smelting process
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GENETIC OPTIMIZATION OF HOT FILAMENT PARAMETERS IN HFCVD SYSTEM
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作者 宋胜利 左敦稳 +3 位作者 王珉 相炳坤 卢文壮 黎向锋 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第1期42-46,共5页
In HFCVD system the substrate temperature is a key factor which deeply affects the quality of diamond films. Th e magnitude and the variation of the substrate temperature must be limited in a suitable range to depo... In HFCVD system the substrate temperature is a key factor which deeply affects the quality of diamond films. Th e magnitude and the variation of the substrate temperature must be limited in a suitable range to deposit diamond films of uniform thickness over large areas. In this paper, the hot filament parameters are investigated on the basi s of GAs to realize a good substrate temperature profile. Computer simulations d emonstrate that on parameters optimized by GAs a uniform substrate temperatur e field can be formed over a relatively large circle area with R s=10 cm. 展开更多
关键词 hot filament chemical vapor deposition temperature field genetic algorithms optimization diamond fi lm
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Thermodynamics for chemical vapor synthesis of Nb nanopowder in NbCl_5-H_2-Ar system
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作者 朱骏 黄凯 +1 位作者 侯军刚 朱鸿民 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期3987-3993,共7页
Thermodynamics for chemical vapor synthesis (CVS) of Nb nanopowder in NbCl5-H2-Ar system was investigated by using FactSage software. The validation experiments were conducted to confirm the thermodynamics points. T... Thermodynamics for chemical vapor synthesis (CVS) of Nb nanopowder in NbCl5-H2-Ar system was investigated by using FactSage software. The validation experiments were conducted to confirm the thermodynamics points. The results indicate that under the atmospheric pressure, the reduction approach from NbCl5(g) to Nb(s) is a stage-wise process with the formation of complex sub-chlorides, and is controllable at low hydrogen ratio (mole ratio of n(NbCl5):n(H2)&lt;1:180) and low temperature (&lt;1050 &#176;C). Furthermore, a reasonable amount of inert loading gas is favorable to increase the reduction ratio of NbCl5 and the powder yield. The as-synthesized Nb nanopowder with the homogeneous size of 30-50 nm and the powder yield of 85% (mass fraction) is obtained by the CVS process under n(NbCl5):n(H2):n(Ar)=1:120:1 and 950 &#176;C with the NbCl5 reduction rate of 96.1%. 展开更多
关键词 NbCl5-H2-Ar system chemical vapor synthesis (CVS) thermodynamic niobium nanopowder FactSage software
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Evaluation of greenlight photoselective vaporization of the prostate for the treatment of high-risk patients with benign prostatic hyperplasia 被引量:12
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作者 Wei-Jun Fu Bao-Fa Hong Xiao-Xiong Wang Yong Yang Wei Cai Jiang-Ping Gao Yao-Fu Chen Cui-E Zhang 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第3期367-371,共5页
Aim: To explore the feasibility and safety of greenlight photoselective vaporization of the prostate (PVP) on high-risk patients presenting with lower urinary tract symptoms suggestive of benign prostatic hyperplas... Aim: To explore the feasibility and safety of greenlight photoselective vaporization of the prostate (PVP) on high-risk patients presenting with lower urinary tract symptoms suggestive of benign prostatic hyperplasia (BPH) and to evaluate their clinical and voiding outcome. Methods: A total of 85 high-risk patients with obstructive BPH underwent PVP with an 80 W potassium-titanyl-phosphate laser, which was delivered through a side-deflecting fiber with a 23 Fr continuous flow cystoscope. Operative time, blood loss, indwelling catheterzation, international prostate symptom score (IPSS), quality of life score (QoL), uroflowmetry, postvoid residual urine volume and short-term complication rates were evaluated for all patients. Results: All patients got through the perioperative period safely. The chief advantages of PVP were: short operative time (25.6 ± 7.6 min), little bleeding loss (56.8 ± 14.3 mL) and short indwelling catheterization (1.6 ± 0.8 d). The IPSS and QoL decreased from (29.6 ± 5.4) and (5.4 ± 0.6) to (9.5 ± 2.6) and (1.3 ± 0.6), respectively. The vast majority of patients were satisfied with voiding outcome. The mean maximal urinary flow rate increased to 17.8 mL/s and postvoid residual urine volume decreased to 55.6 mL. These results are significantly different from preoperative data (P 〈 0.05). No patient required blood transfusion or fluid absorption. There were few complications and very high patient satisfaction after operation. Conclusion: PVP has a short operative time and high tolerance, and is safe, effective and minimally invasive for high-risk patients, therefore it might be considered as a good alternative treatment for high-risk patients with obstructive urinary symptoms as a result of BPH. 展开更多
关键词 benign prostatic hyperplasia photoselective vaporization of the prostate HIGH-RISK laser surgery PROSTATE
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Thermal behaviors and heavy metal vaporization of phosphatized tannery sludge in incineration process 被引量:11
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作者 TANG, Ping ZHAO, Youcai XIA, Fengyi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第9期1146-1152,共7页
The high concentration of heavy metal (Cu, Cr, Zn, Pb) in tannery sludge causes severe heavy metal emissions in the process of incineration. In the present investigation, the tannery sludge was treated with 85% phosph... The high concentration of heavy metal (Cu, Cr, Zn, Pb) in tannery sludge causes severe heavy metal emissions in the process of incineration. In the present investigation, the tannery sludge was treated with 85% phosphoric acid before the incineration process in the tube furnace to control the heavy metal emissions. The thermal behavior and heavy metal vaporization of pre-treated tannery sludge were investigated, and X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were also implemente... 展开更多
关键词 tannery sludge thermal behavior heavy metal vaporization phosphatation
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Preliminary Study on the Vaporization Ratio of the Slurry in the Residue Fluid Catalytic Cracking Disengager 被引量:5
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作者 闫平祥 蓝兴英 +1 位作者 徐春明 高金森 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第3期315-319,共5页
The vaporization ratios of the slurry at various temperature and partial pressure were calculated with the group-contribution method,and then the phase state of the slurry in the residue fluid catalytic cracking(RFCC)... The vaporization ratios of the slurry at various temperature and partial pressure were calculated with the group-contribution method,and then the phase state of the slurry in the residue fluid catalytic cracking(RFCC) disengager was determined.This research could provide some advices on how to select the technological conditions to decrease the coking in the RFCC disengager.The oil gas temperature and the slurry partial pressure had signifi- cant effects on the vaporization ratio of the slurry.Increasing the oil gas temperature and reducing the slurry partial pressure could effectively slow down the coking speed in the RFCC disengager.According to the calculation results, a correlation was established to predict the vaporization ratio of the slurry under different operating conditions. 展开更多
关键词 DISENGAGER SLURRY group-contribution method vaporization ratio correlation model
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Effects of imidazolium-based ionic liquids on the isobaric vapor–liquid equilibria of methanol+dimethyl carbonate azeotropic systems 被引量:4
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作者 Songsong Chen Li Dong +4 位作者 Junping Zhang Weiguo Cheng Feng Huo Qian Su Wei Hua 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第3期766-776,共11页
The separation of methanol(MeOH)and dimethyl carbonate(DMC)is important but difficult due to the formation of an azeotropic mixture.In this work,isobaric vapor–liquid equilibrium(VLE)data for the ternary systems cont... The separation of methanol(MeOH)and dimethyl carbonate(DMC)is important but difficult due to the formation of an azeotropic mixture.In this work,isobaric vapor–liquid equilibrium(VLE)data for the ternary systems containing different imidazolium–based ionic liquids(ILs),i.e.MeOH+DMC+1-butyl-3-methy-limidazolium bis[(trifluoromethyl)sulfonyl]imide([Bmim][Tf2N]),MeOH+DMC+1-ethyl-3-methyl-imidazolium bis[(trifluoromethyl)sulfonyl]imide([Emim][Tf2N]),and MeOH+DMC+1-ethyl-3-methylimidazolium hexafluorophosphate([Emim][PF6])were measured at 101.3 kPa.The mole fraction of IL was varied from0.05 to 0.20.The experimental data were correlated with the NRTL and Wilson equations,respectively.The results show that imidazolium-based ILs were beneficial to improve the relative volatility of MeOH to DMC,and[Bmim][Tf2 N]showed a much more excellent performance on the activity coefficient of MeOH.The interaction energies of system components were calculated using Gaussian program,and the effects of cation and anion on the separation coefficient of the azeotropic system were discussed. 展开更多
关键词 Vapor liquid equilibria Ionic liquid AZEOTROPE Separation Interaction energy
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Monitoring and simulation of water,heat,and CO_2 fluxes in terrestrial ecosystems based on the APEIS-FLUX system 被引量:4
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作者 WATANABEMasataka WANGQinxue +6 位作者 HAYASHISeiji MURAKAMIShogo LIUJiyuan OUYANGZhu LIYan LIYingnian WANGKelin 《Journal of Geographical Sciences》 SCIE CSCD 2005年第2期131-141,共11页
The Integrated Environmental Monitoring (IEM) project, part of the Asia-Pacific Environmental Innovation Strategy (APEIS) project, developed an integrated environmental monitoring system that can be used to detect, mo... The Integrated Environmental Monitoring (IEM) project, part of the Asia-Pacific Environmental Innovation Strategy (APEIS) project, developed an integrated environmental monitoring system that can be used to detect, monitor, and assess environmental disasters, degradation, and their impacts in the Asia-Pacific region. The system primarily employs data from the moderate resolution imaging spectrometer (MODIS) sensor on the Earth Observation System-(EOS-) Terra/Aqua satellite, as well as those from ground observations at five sites in different ecological systems in China. From the preliminary data analysis on both annual and daily variations of water, heat and CO2 fluxes, we can confirm that this system basically has been working well. The results show that both latent flux and CO2 flux are much greater in the crop field than those in the grassland and the saline desert, whereas the sensible heat flux shows the opposite trend. Different data products from MODIS have very different correspondence, e.g. MODIS-derived land surface temperature has a close correlation with measured ones, but LAI and NPP are quite different from ground measurements, which suggests that the algorithms used to process MODIS data need to be revised by using the local dataset. We are now using the APEIS-FLUX data to develop an integrated model, which can simulate the regional water, heat, and carbon fluxes. Finally, we are expected to use this model to develop more precise high-order MODIS products in Asia-Pacific region. 展开更多
关键词 APEIS-FLUX system Asia-Pacific Environmental Innovation Strategy (APEIS) CO2 flux Integrated Environmental Monitoring (IEM) MODIS water vapor flux
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Vapour-Liquid Equilibrium with a New Ebulliometer:Ester+Alcohol System at 0.5 MPa 被引量:2
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作者 P. Susial A. Sosa-Rosario R. Rios-Santana 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第6期1000-1007,共8页
A new dynamic ebulliometer is used to determine vapor-liquid equilibrium(VLE) data experimentally. In the equipment,both phases are recirculated. Its operation is a consequence of the Cotrell pump effect produced when... A new dynamic ebulliometer is used to determine vapor-liquid equilibrium(VLE) data experimentally. In the equipment,both phases are recirculated. Its operation is a consequence of the Cotrell pump effect produced when the mixture is heated in a double-walled inverted vessel. The reliability of the apparatus is tested with the mixtures studied previously by various authors. VLE data for the binary systems of methyl acetate + methanol and the methyl acetate + ethanol at 0.5 MPa are determined. The experimental data are confirmed with the point-to-point test of van Ness,applying the Fortran program of Frendslund et al. In addition,the experimental results are com-pared with the UNIFAC(including different versions) and ASOG prediction models. 展开更多
关键词 vapor-liquid equilibrium vapor-liquid equilibrium apparatus vapor pressure ALCOHOL
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Energy Efficient Predictive Control for Vapor Compression Refrigeration Cycle Systems 被引量:3
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作者 Xiaohong Yin Shaoyuan Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第5期953-960,共8页
Abstract--Vapor compression refrigeration cycle (VCC) system is a high dimensional coupling thermodynamic system for which the controller design is a great challenge. In this paper, a model predictive control based ... Abstract--Vapor compression refrigeration cycle (VCC) system is a high dimensional coupling thermodynamic system for which the controller design is a great challenge. In this paper, a model predictive control based energy efficient control strategy which aims at maximizing the system efficiency is proposed. Firstly, according to the mass and energy conservation law, an analysis on the nonlinear relationship between superheat and cooling load is carried out, which can produce the maximal effect on the system performance. Then a model predictive control (MPC) based controller is developed for tracking the calculated setting curve of superheat degree and pressure difference based on model identified from data which can be obtained from an experimental rig. The proposed control strategy maximizes the coefficient of performance (COP) which depends on operating conditions, in the meantime, it meets the changing demands of cooling capacity. The effectiveness of the control performance is validated on the experimental rig. Index Terms--Cooling load, model predictive control (MPC), superheat, vapor compression refrigeration cycle (VCC). 展开更多
关键词 Cooling load model predictive control(MPC) SUPERHEAT vapor compression refrigeration cycle(VCC)
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Prediction of Vapor-Liquid Equilibrium Data from C—H Band Shift of IR Spectra in Some Binary Systems 被引量:2
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作者 朱霄 姚加 +1 位作者 李浩然 韩世钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第1期97-101,共5页
Prediction of vapor-liquid equilibrium (VLE) is extremely necessary to separate liquid mixture in chemical production, especially when the required experimental data are difficult to measure, or the measurement is n... Prediction of vapor-liquid equilibrium (VLE) is extremely necessary to separate liquid mixture in chemical production, especially when the required experimental data are difficult to measure, or the measurement is not economical. The infinite dilution activities can be used to predict VLE. However, it needs both the ends of the activities that are difficult to obtain for many systems. In the present study, a new model is proposed for correlating the frequency shift of C-H stretching band of IR spectra over the whole concentration. Investigated mixtures in- clude water/2-propanol, water/N, N-dimethylformamide (DMF), water/methanol, water/ethanol, water/1, 4-dioxane, and water/dimethylsulfoxide (DMSO) systems. Simultaneous correlations of C--H frequency shift and VLE data are made. Furthermore, the VLE data were predicted with satisfactory results by the parameters obtained from IR spectra coupled with one ot the intinite chlution activity coefficients. 展开更多
关键词 IR vapor liquid equilibrium infinite dilution activity coefficient binary aqueous system
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Experimental results for the vapor-liquid equilibria of 0(formaldehyde+1,3,5-trioxane+methanol+salt+water)systems and comparison with predictions 被引量:2
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作者 Xianming Zhang Mengchen Li +2 位作者 Yufeng Hu Zhichang Liu Shuqin Mo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第4期291-300,共10页
The salt effect on the vaporliquid phase equilibrium(VLE)of solvent mixtures is of significant interest in the industrial production of 1,3,5trioxane.Experimental data for the VLE of quinary systems(formaldehyde+1,3,5... The salt effect on the vaporliquid phase equilibrium(VLE)of solvent mixtures is of significant interest in the industrial production of 1,3,5trioxane.Experimental data for the VLE of quinary systems(formaldehyde+1,3,5trioxane+methanol+salt+water)and their ternary subsystems(formaldehyde+salt+water),(1,3,5trioxane+salt+water),and(methanol+salt+water)were systematic measured under atmospheric pressure.The salts considered included KBr,NaNO_(3),and CaCl_(2).The extended UNIFAC model was used to describe the VLE of the saltcontaining reactive mixtures.The model parameters were determined from the experimental VLE data of ternary systems or obtained from the literature,and then were used to predict the VLE of systems(1,3,5trioxane+KBr+water),(methanol+KBr+water),(formaldehyde+KBr+water),and(formaldehyde+1,3,5trioxane+methanol+salt+water)with salt=KBr,NaNO_(3),and CaCl_(2).The predicted results showed good agreements with the measured results.Furthermore,the model was used to uncover the salt effect on the VLE of these multisolvent reactive systems. 展开更多
关键词 Vapor liquid equilibria Reactive distillation Activity coefficient 1 3 5-Trioxane production UNIFAC Salt effect
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Performance comparison and analysis of a combined power and cooling system based on organic Rankine cycle 被引量:2
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作者 王志奇 周奇遇 +2 位作者 夏小霞 刘斌 张欣 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期353-359,共7页
A novel power and cooling system combined system which coupled organic Rankine cycle(ORC) with vapor compression refrigeration cycle(VCRC) was proposed. R245 fa and butane were selected as the working fluid for the po... A novel power and cooling system combined system which coupled organic Rankine cycle(ORC) with vapor compression refrigeration cycle(VCRC) was proposed. R245 fa and butane were selected as the working fluid for the power and refrigeration cycle, respectively. A performance comparison and analysis for the combined system was presented. The results show that dual-pressure ORC-VCRC system can achieve an increase of 7.1% in thermal efficiency and 6.7% in exergy efficiency than that of basic ORC-VCRC. Intermediate pressure is a key parameter to both net power and exergy efficiency of dual-pressure ORC-VCRC system. Combined system can produce maximum net power and exergy efficiency at 0.85 MPa for intermediate pressure and 2.4 MPa for high pressure, respectively. However, superheated temperature at expander inlet has little impact on the two indicators. It can achieve higher overall COP, net power and exergy efficiency at smaller difference between condensation temperature and evaporation temperature of VCRC. 展开更多
关键词 dual-pressure organic Rankine cycle vapor compression refrigeration waste heat performance analysis
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Treatment satisfaction after I year high-power potassiumtitanyl-phosphate photoselective vaporization of the prostate 被引量:1
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作者 Ja Hyeon Ku Min Chul Cho Hyeong Seok Kim Jae-Seung Paick Soo Woong Kim 《Asian Journal of Andrology》 SCIE CAS CSCD 2010年第5期728-734,共7页
To investigate the factors that influence treatment satisfaction after high-power potassium-titanyl-phosphate (KTP) laser vaporization of the prostate, we compared the characteristics between patients who were satis... To investigate the factors that influence treatment satisfaction after high-power potassium-titanyl-phosphate (KTP) laser vaporization of the prostate, we compared the characteristics between patients who were satisfied and those who were not satisfied. In all, 97 patients aged between 53-82 years (median age 67 years) underwent high-power KTP laser vaporization of the prostate for lower urinary tract symptoms due to benign prostatic hyperplasia. At 12 months postoperatively, 60 patients were satisfied with the treatment, whereas 37 were dissatisfied. Although there were no differences in International Prostate Symptom Score (IPSS) values at baseline, the satisfied group scored better in total IPSS at 1, 3, 6, and 12 months postoperatively (P 〈 0.05). At baseline, the maximum flow rate (Qmax) was lower in the dissatisfied group and remained low throughout the follow-up period, with the exception of 1 month postoperatively (P 〈 0.05), compared with the satisfied group. There were no differences in other objective data between the two groups, including post-void residual and the number of voids based on the frequency-volume charts. In a multivariate model, a higher bladder contractility index was associated with a greater likelihood of treatment satisfaction 12 months after high-power KTP laser vaporization (odds ratio 1.024, 95% confidence interval 1.001-1.048, P 〈 0.05). Patients who were not satisfied following the surgery had a smaller improvement in subjective symptoms and Qmax. In addition, our findings suggest that the relative risk of treatment dissatisfaction following high-power KTP laser vaporization was increased in patients with weak detrusor contractility. 展开更多
关键词 benign prostatic hyperplasia potassium-titanyl-phosphate PROSTATE SATISFACTION vaporization
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Vapor Pressure, Vaporization Enthalpy, Standard Enthalpy of Formation and Standard Entropy of n-Butyl Carbamate 被引量:1
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作者 曾作祥 杨志红 +1 位作者 薛为岚 李晓楠 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第10期1145-1152,共8页
The vapor pressures of n-butyl carbamate were measured in the temperature range from 372.37 K to 479.27 K and fitted with Antoine equation. The compressibility factor of the vapor was calculated with the Virial equati... The vapor pressures of n-butyl carbamate were measured in the temperature range from 372.37 K to 479.27 K and fitted with Antoine equation. The compressibility factor of the vapor was calculated with the Virial equation and the second virial coefficient was determined by the Vetere model. Then the standard enthalpy of vaporization for n-butyl carbamate was estimated. The heat capacity was measured for the solid state(299.39–324.2 K) and liquid state(336.65–453.21 K) by means of adiabatic calorimeter. The standard enthalpy of formation ΔfH[crystal(cr),298.15 K] and standard entropy S(crystal,298.15 K) of the substance were calculated on the basis of the gas-phase standard enthalpy of formation ΔfH(g,298.15 K)and gas-phase standard entropy S(g,298.15 K), which were estimated by the Benson method. The results are acceptable, validated by a thermochemical cycle. 展开更多
关键词 N-BUTYL CARBAMATE Vapor pressure STANDARD ENTHALPY of FORMATION STANDARD ENTROPY
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