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Determination of Paclitaxel Solubility in carbon dioxide Using Quartz Crystal Microbalance

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Chinese Journal of Chemical Engineering 2011年第2期19卷 227-231页

作者：焦真陈志明吴有庭马少玲 School of Chemistry and Chemical Engineering Southeast University Nanjing 211189 China School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

A quartz crystal microbalance （QCM） is used to determine the phase equilibrium of paclitaxel-carbon dioxide system in the pressure range of 0-11 MPa and at temperatures of 35 °C,40 °C and 45 °*** experimental results indicated that gaseous CO2 could be absorbed poorly into *** swelling of paclitaxel film in CO2 was observed before paclitaxel dissolved into supercritical carbon dioxide （ScCO2） with the increase of *** was found that ScCO2 was not a good solvent for *** mole fraction of paclitaxel in ScCO2 was in the range of （4.5×10-9）-（7.8×10-9） under all our experimental ***,a much higher pressure than the CO2 supercritical point and/or a cosolvent must be used in any processes wherever paclitaxel dissolution in ScCO2 is required.

关键词： paclitaxel carbon dioxide phase behavior quartz crystal microbalance

INFLUENCE OF DIALKYLZINC IN RARE-EARTH TERNARY CATALYST ONTHE COPOLYMERIZATION OF carbon dioxide AND PROPYLENE OXIDE

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Chinese Journal of Polymer Science 2005年第6期23卷 671-674页

作者： Dong Xie Xian-hong Wang Xiao-jiang Zhao and Fo-song Wang Polymer Material Engineering Lab,Changchun Institute of Applied Chemistry,Graduate School of Chinese Academy of Sciences,Changchun 130022,China Polymer Material Engineering Lab Changchun Institute of Applied Chemistry Graduate School of Chinese Academy of Sciences Changchun 130022 China

Rare-earth ternary catalysts Y（CCl3COO）3-ZnR2-glycerin were prepared for the copolymerization of carbon dioxide and propylene oxide （PO）, where dialkylzincs （ZnR2） were diethylzinc, di（n-propyl）zinc, di（n-butyl）zinc, di（i-propyl）zinc, di（i-butyl）zinc, di（s-butyl）zinc,respectively. The Y（CCl3COO）3-ZnR2-glycerin catalysts displayed the highest catalytic activity at the molar ratio of Y（CCl3COO）3：ZnR2：glycerin = 1：20：10. In the same copolymerization condition, catalysts containing dialkylzincs with branched alkyl group showed lower catalytic activity than that with primary alkyl group. For those catalysts including dialkylzincs with primary alkyl group, their catalytic activity decreases with increasing number of carbon atom in the alkyl group with the following sequence： Y（CCl3COO）3-ZnEt2-glycerin 〉 Y（CCl3COO）3-Zn（n- Pr）2-glycerin〉Y（CCl3COO）3-Zn（n-Bu）2-glycerin. However, the alkyl group in the dialkylzinc does not influence the insertion of PO into the propagation chain end.

关键词： carbon dioxide Propylene oxide Copolymerization Dialkylzinc

Polyethylene glycol radical-initiated aerobic propargylic oxidation in dense carbon dioxide

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Journal of Energy Chemistry 2013年第3期22卷 363-367页

作者： Zhenfeng Diao Bin Li Bing Yu Anhua Liu Liangnian He State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

The selective aerobic oxidation of alkynes to corresponding α,β-acetylenic ketones was achieved in polyethylene glycol/dense CO2/O2 biphasic system without any catalyst or additive. The effects of reaction parameters, e.g. temperature, CO2 pressure, PEG molecular weight and loading on the reaction were carefully examined. Moreover, various substrates worked well in the presence of PEG 1000 under 5 MPa of CO2 and 2 MPa of O2 at 100 ℃ for 12 to 24 h and acceptable yield and selectivity could be obtained in most cases. Preliminary mechanistic investigations were also discussed.

关键词： carbon dioxide polyethylene glycol selective oxidation alkynes β-acetylenic ketones

Ellipticity-dependent ionization/dissociation of carbon dioxide in strong laser fields

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Chinese Physics B 2015年第3期24卷 122-126页

作者：张军峰马日左万龙吕航黄红卫徐海峰金明星丁大军 Institute of Atomic and Molecular Physics Jilin University Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy Jilin University

Ionization and dissociation of linear triatomic molecules, carbon dioxide, are studied in 50-fs 800-nm strong laser fields using time-of-flight mass spectrometer. The yields of double charged ions CO2^2＋ and various fragment ions（CO^＋,O^n＋, and C^n＋（n = 1, 2）） are measured as a function of ellipticity of laser polarization in the intensity range from 5.0 ×10^13W/cm2 to 6.0 × 10^14W/cm^2. The results demonstrate that non-sequential double ionization, which is induced by laser-driven electron recollision, dominates double ionization of CO2 in the strong IR laser field with intensity lower than2.0 × 10^14W/cm^2. The electron recollision could also have contribution in strong-field multiple ionization and formation of fragments of CO2 molecules. The present study indicates that the intensity and ellipticity dependence of ions yields can be used to probe the complex dynamics of strong-field ionization/dissociation of polyatomic molecules.

关键词： laser ellipticity strong field ionization and dissociation carbon dioxide

A Fully Flexible Potential Model for carbon dioxide

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Chinese Journal of Chemical Engineering 2009年第2期17卷 268-272页

作者：朱爱梅张新波刘庆林张秋根 National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters Department of Chemical and Biochemical Engineering College of Chemistry & Chemical Engineering Xiaman University Xiamen 361005 China

A fully flexible potential model for carbon dioxide has been developed to predict the vapor-liquid coexistence properties using the NVT-Gibbs ensemble Monte Carlo technique(GEMC).The average absolute deviation between our simulation and the literature experimental data for saturated liquid and vapor densities is 0.3% and 2.0%,*** with the experimental data,our calculated results of critical properties(7.39 MPa,304.04 K,and 0.4679 g?cm-3) are acceptable and are better than those from the rescaling the potential parameters of elementary physical model(EPM2).The agreement of our simulated densities of supercritical carbon dioxide with the experimental data is acceptable in a wide range of pressure and *** radial distribution function estimated at the supercritical conditions suggests that the carbon dioxide is a nonlinear molecule with the C O bond length of 0.117 nm and the O C O bond angle of 176.4°,which are consistent with Car-Parrinello molecular-dynamics(CPMD),whereas the EPM2 model shows large deviation at supercritical *** predicted self-diffusion coefficients are in agreement with the experiments.

关键词： molecular simulations radial distributions fully flexible potential model carbon dioxide

Fast-and ultra-fast laser pulse induced reactions between carbon dioxide and methane

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Journal of Natural Gas Chemistry 2010年第2期19卷 198-202页

作者： F.Jaco Kotze Christien A.Strydom Anton du Plessis Thulani L.Dlamini School of Physical and Chemical Science Faculty of ScienceNorth West UniversityPrivate Bag X6001Potchefstroom 2520South Africa CSIR National Laser Centre P O Box 395Pretoria 0001South Africa

The direct excitation of CO2 using fast （nanosecond） and ultrafast （femtosecond） pulsed lasers was investigated.A gas reaction cell was used to excite CO2 in a 50：50 mixture of CO2 and CH4 using nano-and femtosecond laser systems,to induce a reaction between these two ***-IR spectra showed that CO was formed using the nanosecond and femtosecond laser *** was also found that hydrocarbons,containing C-C bonds were *** both the nanosecond and femtosecond laser,it was found that more C-C higher hydrocarbons were formed after 5 h compared to 3 h of *** at pressures of 250,350 and 500 kPa with the femtosecond laser system showed the expected increase in the amount of CO formed with an increase in *** from this study showed that carbon dioxide and methane can be activated successfully using nanosecond laser pulses at 2000 nm and femtosecond laser pulses at 795 or 2000 nm and that these activated species react to form CO and C-C containing products.

关键词： nanosecond femtosecond tuneable laser systems carbon dioxide methane

Molecular Simulation of carbon dioxide Adsorbed in a Slit carbon Pore

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Chinese Journal of Chemical Engineering 2001年第1期9卷 34-38页

作者：周健汪文川北京化工大学北京

Both the grand canonical Monte Carlo and molecular dynamics simulation methods are used to investigate the adsorption and diffusion of carbon dioxide confined in a 1.86 nm slit carbon pore at 4 temperatures from subcritical (120 K) to supercritical (313 K) conditions. Layering transition, capillary condensation and adsorption hysteresis are found at 120 K. The microstructure of carbon dioxide fluid in the slit carbon pore is analyzed. The diffusion coefficients of carbon dioxide parallel to the slit wall are significantly larger than those normal to the slit wall.

关键词： carbon dioxide molecular simulation grand canonical Monte Carlo molecular dynamics adsorption diffusion slit pore

carbon dioxide-angiography for patients with peripheral arterial disease at risk of contrast-induced nephropathy

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World Journal of Cardiology 2020年第2期12卷 76-90页

作者： Amol Gupta Akinsansoye K Dosekun Vinod Kumar Department of Cardiology HeartVascular and Leg CenterBakersfieldCA 93309United States Department of Nephrology University of TexasHoustonTX 77030United States

Patients with peripheral arterial disease(PAD)and critical limb ischemia are at risk for limb amputation and require urgent management to restore blood *** with PAD often have several comorbidities,including chronic kidney disease,diabetes mellitus,and *** and interventional angiography using iodinated contrast agents provides excellent image resolution but can be associated with contrast-induced nephropathy(CIN).The use of carbon dioxide(CO2)as a contrast agent reduces the volume of iodine contrast required for angiography and reduces the incidence of ***,CO2 angiography has been underutilized due to concerns regarding safety and image *** CO2 delivery systems with advanced digital subtraction angiography techniques and hybrid angiography have improved imaging accuracy and reduced the incidence of *** of the need for optimal imaging conditions,contraindications,and potential complications have improved the safety of CO2 *** review aims to highlight current technological advances in the delivery of CO2 in vascular angiography for patients with PAD and critical limb ischemia,which result in limb preservation while preventing kidney damage.

关键词： Endovascular procedures Angiography Digital subtraction Chronic kidney disease Peripheral artery disease carbon dioxide

MEASUREMENTS OF MONOMER REACTIVITY RATIOS FOR COPOLYMERIZATION OF STYRENE AND METHYL METHACRYLATE IN carbon dioxide AT VAPOR-LIQUID EQUILIBRIUM STATE

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Chinese Journal of Polymer Science 2009年第3期27卷 367-374页

作者：胡春圃 Key Laboratory of Ultrafine Materials Ministry of Education School of Materials Science and Engineering East China University of Science and Technology

The monomer reactivity ratios of free radical copolymerization of styrene and methyl methacrylate in carbon dioxide at vapor-liquid equilibrium state (vlCO(2)) at 65 degrees C and under 7.5-8.5 MPa were measured. The experimental results showed that, in comparison with the data in bulk copolymerization, the monomer reactivity ratio of St in vlCO(2) increased acompanied by a somewhat decrease in that of MMA. Further analysis of the sequence distributions of these copolymers by H-1-NMR spectra indicated that there was a significant bootstrap effect in this system. The local monomer concentrations in the proximity of growing free radicals, rather than the true reactivity of monomers or free radicals, were altered by the presence of vlCO(2), leading to the change in monomer reactivity ratios.

关键词： Monomer reactivity ratios Free radical copolymerization carbon dioxide Styrene Methyl methacrylate