Growth kinetics of the most stable polymorph of calcium carbonate,calcite,has been studied in seeded stirred batch experiments in MEG-water solutions at 40 ℃ and 70 ℃,conditions relevant for the processing of natura...Growth kinetics of the most stable polymorph of calcium carbonate,calcite,has been studied in seeded stirred batch experiments in MEG-water solutions at 40 ℃ and 70 ℃,conditions relevant for the processing of natural gas.It was found that MEG changes the growth order from two in pure water to one in solvent mixtures of MEG and water.Assuming parabolic growth (growth order is equal to two),it could be shown that MEG decreases the growth rate constant for calcite from 0.52 nm/s to 0.11 nm/s (70 ℃) when the MEG-content is increased from 0 wt% MEG to 65 wt% MEG.Decreasing the temperature from 70 ℃ to 40 ℃ has a similar effect on the growth rate constant as raising the level of MEG to 65 wt%.展开更多
A synthesis route of using calcium hydroxide Ca(OH)2 with ethylene glycol solvent and orthophosphoric acid (H3PO4) as reagents is described. Three ratios of ethylene glycol to distilled water 1:0, 1:1 and 0:1 are used...A synthesis route of using calcium hydroxide Ca(OH)2 with ethylene glycol solvent and orthophosphoric acid (H3PO4) as reagents is described. Three ratios of ethylene glycol to distilled water 1:0, 1:1 and 0:1 are used as diluting media for Ca(OH)2. Crystals of different morphology and composition are formed under weak alkaline circumstance at pH 7.0-8.0. Acicular calcium phosphate nanocrystals are prepared in pure ethylene glycol while rod-like calcium phosphate nanocrystals form in pure distilled water. The nanograde size of the former is smaller than that of the latter. Calcium-deficient apatite (CDAP) is obtained with a Ca/P molar ratio of 1.66. Therefore, it was deduced that the usage of ethylene glycol solvent could influence the formation of calcium phosphate crystal lattice.展开更多
The aim of the present study was to develop a novel long-acting Poly(lactic-co-glycolic acid)(PLGA)-based microspheres formulation of Bisdemethoxycurcum(BDMC) by emulsionsolvent evaporation method. Meanwhile, the effe...The aim of the present study was to develop a novel long-acting Poly(lactic-co-glycolic acid)(PLGA)-based microspheres formulation of Bisdemethoxycurcum(BDMC) by emulsionsolvent evaporation method. Meanwhile, the effects of the volume ratio of the dispersed phase and continuous phase, the concentration of PLGA and PVA, the theoretical drug loading and stirring speed were investigated. The mean diameter of the microspheres was 8.5 μm and the size distribution was narrow. The encapsulation efficiency(EE) and drug loading efficiency(DLE) of BDME loaded PLGA microspheres(BDMC-PLGA-MS) was 94.18% and 8.14%,respectively. In an in vitro study of drug release, it can be concluded that the BDMC-PLGAMS exhibited sustained and long-term release properties for 96 h. Stability studies suggested that the microspheres we prepared had a very good stability. Furthermore, the results of an in vivo study indicated that the BDMC-PLGA-MS had sustained release effect and was mainly distributed in the lung tissue, and less distribution in other tissues, which indicated that microspheres could be an effective parenteral carrier for the delivery of BDMC in lung cancer treatment.展开更多
A theoretical analysis of the influence of the flow of a coolant containing silver nanoparticle (Ag) in an automotive radiator is presented. The coolant fluid is composed of water or an aqueous solution of Ethylene-Gl...A theoretical analysis of the influence of the flow of a coolant containing silver nanoparticle (Ag) in an automotive radiator is presented. The coolant fluid is composed of water or an aqueous solution of Ethylene-Glycol (EG50%) and silver nanoparticles. Ethylene glycol (EG) has been used in automobile radiators for many years due to its compatibility with metals and its anti-cooling properties. Silver nanoparticles are being incorporated into the development of high-precision surgical equipment. It is shown that the rate of heat transfer increases significantly using silver nanoparticles and ethylene glycol and water. There is a maximum for heat exchange between fluids in all analyzed coolant flows—the maximum moves to higher airflow rates when the coolant flow rate is increased. However, the energy dissipation in the stream also increases, but the relationship between the energy dissipated in the flow and the energy transferred in the form of heat is low, which justifies the use of silver nanoparticles and ethylene glycol, or silver nanoparticles and water as a coolant in the automotive vehicle radiator.展开更多
Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free co...Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free conditions. The reactants were ground in a mortar with a pestle for about 30 minutes. The aromatic acids underwent nitro decarboxylation and afforded β-nitro styrene derivatives in very good yield while α, β-unsaturated aliphatic carboxylic acids gave corresponding nitro derivatives. Addition of PEG accelerated rate of the reaction enormously. Reaction times substantially decreased from several hours to few minutes followed by highly significant increase in the product yield. Among the several PEGs PEG-300 has been found to be much more effective than other PEGs.展开更多
基金Supported by the Kjeller MEG Loop II project including support from Aker Solutions,BG Group,Cameron,Chevron,Petrobras,Petronas,Shell,Statoil,Total,Woodsidea grant from the Research Council of Norway under contract 207537/E30
文摘Growth kinetics of the most stable polymorph of calcium carbonate,calcite,has been studied in seeded stirred batch experiments in MEG-water solutions at 40 ℃ and 70 ℃,conditions relevant for the processing of natural gas.It was found that MEG changes the growth order from two in pure water to one in solvent mixtures of MEG and water.Assuming parabolic growth (growth order is equal to two),it could be shown that MEG decreases the growth rate constant for calcite from 0.52 nm/s to 0.11 nm/s (70 ℃) when the MEG-content is increased from 0 wt% MEG to 65 wt% MEG.Decreasing the temperature from 70 ℃ to 40 ℃ has a similar effect on the growth rate constant as raising the level of MEG to 65 wt%.
基金We would like to acknowledge the support from the Ministry of Science and Technology of China(2001BA310A).
文摘A synthesis route of using calcium hydroxide Ca(OH)2 with ethylene glycol solvent and orthophosphoric acid (H3PO4) as reagents is described. Three ratios of ethylene glycol to distilled water 1:0, 1:1 and 0:1 are used as diluting media for Ca(OH)2. Crystals of different morphology and composition are formed under weak alkaline circumstance at pH 7.0-8.0. Acicular calcium phosphate nanocrystals are prepared in pure ethylene glycol while rod-like calcium phosphate nanocrystals form in pure distilled water. The nanograde size of the former is smaller than that of the latter. Calcium-deficient apatite (CDAP) is obtained with a Ca/P molar ratio of 1.66. Therefore, it was deduced that the usage of ethylene glycol solvent could influence the formation of calcium phosphate crystal lattice.
文摘The aim of the present study was to develop a novel long-acting Poly(lactic-co-glycolic acid)(PLGA)-based microspheres formulation of Bisdemethoxycurcum(BDMC) by emulsionsolvent evaporation method. Meanwhile, the effects of the volume ratio of the dispersed phase and continuous phase, the concentration of PLGA and PVA, the theoretical drug loading and stirring speed were investigated. The mean diameter of the microspheres was 8.5 μm and the size distribution was narrow. The encapsulation efficiency(EE) and drug loading efficiency(DLE) of BDME loaded PLGA microspheres(BDMC-PLGA-MS) was 94.18% and 8.14%,respectively. In an in vitro study of drug release, it can be concluded that the BDMC-PLGAMS exhibited sustained and long-term release properties for 96 h. Stability studies suggested that the microspheres we prepared had a very good stability. Furthermore, the results of an in vivo study indicated that the BDMC-PLGA-MS had sustained release effect and was mainly distributed in the lung tissue, and less distribution in other tissues, which indicated that microspheres could be an effective parenteral carrier for the delivery of BDMC in lung cancer treatment.
文摘A theoretical analysis of the influence of the flow of a coolant containing silver nanoparticle (Ag) in an automotive radiator is presented. The coolant fluid is composed of water or an aqueous solution of Ethylene-Glycol (EG50%) and silver nanoparticles. Ethylene glycol (EG) has been used in automobile radiators for many years due to its compatibility with metals and its anti-cooling properties. Silver nanoparticles are being incorporated into the development of high-precision surgical equipment. It is shown that the rate of heat transfer increases significantly using silver nanoparticles and ethylene glycol and water. There is a maximum for heat exchange between fluids in all analyzed coolant flows—the maximum moves to higher airflow rates when the coolant flow rate is increased. However, the energy dissipation in the stream also increases, but the relationship between the energy dissipated in the flow and the energy transferred in the form of heat is low, which justifies the use of silver nanoparticles and ethylene glycol, or silver nanoparticles and water as a coolant in the automotive vehicle radiator.
文摘Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free conditions. The reactants were ground in a mortar with a pestle for about 30 minutes. The aromatic acids underwent nitro decarboxylation and afforded β-nitro styrene derivatives in very good yield while α, β-unsaturated aliphatic carboxylic acids gave corresponding nitro derivatives. Addition of PEG accelerated rate of the reaction enormously. Reaction times substantially decreased from several hours to few minutes followed by highly significant increase in the product yield. Among the several PEGs PEG-300 has been found to be much more effective than other PEGs.
