The VTLLS microscopy studies were made on high purity gold and commercial grade zinc grains in a temperature range of 30-230?C. Differential area ω and surface activity Sa were estimated from photomicrographs. The ω...The VTLLS microscopy studies were made on high purity gold and commercial grade zinc grains in a temperature range of 30-230?C. Differential area ω and surface activity Sa were estimated from photomicrographs. The ω vs dT/dt (rate of heating) curve was seen to differ from those of silver and titanium. The nature of curve between normalized ω and dT/dt was seen to be non-exponential. The characteristic relation between sectorized differential area ωsec and mean temperature was examined. The present study further establishes the simplicity and versatility of the VTLLS technique, in studying the defect-sub-structure of metal particles such as Au and Zn in presence of an imposed temperature gradient in a reasonable way. As such an attempt was made to connect the ω and defect-sub-structure related parameters.展开更多
我们由使用散布的激光光在答案调查了纤维素 diacetate 的性质。纤维素 diacetate 分子能除单个链以外在丙酮形成微粒和 micellar 簇。作为集中增加,平均水动力学半径 R h 线性地增加,而到水动力学半径 R g/R h 的旋转半径的比率线性...我们由使用散布的激光光在答案调查了纤维素 diacetate 的性质。纤维素 diacetate 分子能除单个链以外在丙酮形成微粒和 micellar 簇。作为集中增加,平均水动力学半径 R h 线性地增加,而到水动力学半径 R g/R h 的旋转半径的比率线性地减少。它显示微粒由于分子间的相互作用联系并且形成 micellar 簇。展开更多
Silver halide (AgX) microcrystal was used as template to synthesize hollow polyelectrolyte capsules. These hollow capsules were characterized by laser light scattering (LLS) used to measure the size of the capsules in...Silver halide (AgX) microcrystal was used as template to synthesize hollow polyelectrolyte capsules. These hollow capsules were characterized by laser light scattering (LLS) used to measure the size of the capsules in solution. The ratio of hydrodynamic radius (R h ) from dynamic LLS to the radius of gyration (Rg) from static LLS is almost unity, revealing that the entities are hollow in solution. The results suggest that the LLS method can be regarded as a good complement to the confocal laser scanning microscopy (CLSM) method for the characterization of small hollow capsules, and it possesses the advantage of not needing fluorescence labeling.展开更多
Durable press finishing of cotton fabrics with polycarboxylic acid increases fabric wrinkle-resistance at the expense of its mechanical strength. Severe tensile strength loss is the major disadvantage for wrinkle resi...Durable press finishing of cotton fabrics with polycarboxylic acid increases fabric wrinkle-resistance at the expense of its mechanical strength. Severe tensile strength loss is the major disadvantage for wrinkle resistant cotton fabrics.Tensile strength loss of cotton fabric crosslinked by a polycarboxylic acid can be attributed to depolymerization and crosslink of cellulose molecules. Measurement of the molecular weight of cotton fabric before and after crosslinked by polycarboxylic acids can offer a possibility of direct understanding of the depolymerization. In this research, amultiple angle laser light scattering photometer was used todetermine the absolute molecular weight of cotton fabric treated with BTCA at different pH and then hydrolyzed with 0. 5 M NaOH solution at 50℃ for 144 h. The results indicate that average molecular weights of cotton fabric treated with polycarboxylic acids at different pH are almost the same.展开更多
The principle of the technique of microscope laser light scattering spectroscopy, its development and applications to the studies on single intact cells, including our work on non-invasive in situ real time measuremen...The principle of the technique of microscope laser light scattering spectroscopy, its development and applications to the studies on single intact cells, including our work on non-invasive in situ real time measurements on single intact erythrocyte simultaneously at the levels of cellular, sub-cellular and intracellular molecules, are introduced.展开更多
A circulating flow system consisting of a transparent U-bend flow loop, a mixing tank and a laser granulometer was set up for studying the kinetics hydrate formation and the pressure is up to 4 MPa. Refrigerant CCl2F2...A circulating flow system consisting of a transparent U-bend flow loop, a mixing tank and a laser granulometer was set up for studying the kinetics hydrate formation and the pressure is up to 4 MPa. Refrigerant CCl2F2 (R12) hydrate formation experiments were performed using laser light scattering method at 277.1 K and pressures of 0.24 and 0.32 MPa. The liquid flow rates were in the range of 300—1400 L/h. The size distribution and density of R12 hydrate particles in pure water were measured using a laser granulometer. Experimental results show that the size of hydrate particles increases sharply at the initial stage and approaches gradually to a stable size. The hydrate particle concentration in the aqueous phase increases with pressure and circulating liquid flow rate. Based on the material balance, the mathematical model among gas consumption, average hydrate particle size and shading ratio has been established. The calculated results using the mathematical model accord well with the experimental gas consumption data.展开更多
文摘The VTLLS microscopy studies were made on high purity gold and commercial grade zinc grains in a temperature range of 30-230?C. Differential area ω and surface activity Sa were estimated from photomicrographs. The ω vs dT/dt (rate of heating) curve was seen to differ from those of silver and titanium. The nature of curve between normalized ω and dT/dt was seen to be non-exponential. The characteristic relation between sectorized differential area ωsec and mean temperature was examined. The present study further establishes the simplicity and versatility of the VTLLS technique, in studying the defect-sub-structure of metal particles such as Au and Zn in presence of an imposed temperature gradient in a reasonable way. As such an attempt was made to connect the ω and defect-sub-structure related parameters.
基金ACKNOWLEDGMENTS This work was supported by China Tobacco Guangdong Industrial Co., Ltd., National Natural Science Foundation of China (No21234003 and No.51303059), and the Fundamental Research Funds for Central Universities.
文摘我们由使用散布的激光光在答案调查了纤维素 diacetate 的性质。纤维素 diacetate 分子能除单个链以外在丙酮形成微粒和 micellar 簇。作为集中增加,平均水动力学半径 R h 线性地增加,而到水动力学半径 R g/R h 的旋转半径的比率线性地减少。它显示微粒由于分子间的相互作用联系并且形成 micellar 簇。
基金This work was supported by the National Natural Science Foundation of China (Grant No. 20204017 and 50373049) and theChinese Academy of Sciences (CMS-CX200308).
文摘Silver halide (AgX) microcrystal was used as template to synthesize hollow polyelectrolyte capsules. These hollow capsules were characterized by laser light scattering (LLS) used to measure the size of the capsules in solution. The ratio of hydrodynamic radius (R h ) from dynamic LLS to the radius of gyration (Rg) from static LLS is almost unity, revealing that the entities are hollow in solution. The results suggest that the LLS method can be regarded as a good complement to the confocal laser scanning microscopy (CLSM) method for the characterization of small hollow capsules, and it possesses the advantage of not needing fluorescence labeling.
基金The Project-sponsored by SRF for ROCS, SEM and EYTP of MOE
文摘Durable press finishing of cotton fabrics with polycarboxylic acid increases fabric wrinkle-resistance at the expense of its mechanical strength. Severe tensile strength loss is the major disadvantage for wrinkle resistant cotton fabrics.Tensile strength loss of cotton fabric crosslinked by a polycarboxylic acid can be attributed to depolymerization and crosslink of cellulose molecules. Measurement of the molecular weight of cotton fabric before and after crosslinked by polycarboxylic acids can offer a possibility of direct understanding of the depolymerization. In this research, amultiple angle laser light scattering photometer was used todetermine the absolute molecular weight of cotton fabric treated with BTCA at different pH and then hydrolyzed with 0. 5 M NaOH solution at 50℃ for 144 h. The results indicate that average molecular weights of cotton fabric treated with polycarboxylic acids at different pH are almost the same.
文摘The principle of the technique of microscope laser light scattering spectroscopy, its development and applications to the studies on single intact cells, including our work on non-invasive in situ real time measurements on single intact erythrocyte simultaneously at the levels of cellular, sub-cellular and intracellular molecules, are introduced.
基金This work was supported by the National 973 of China(Grant No.2001CB209107) National 863 of China(Grant No.2002AA615120).
文摘A circulating flow system consisting of a transparent U-bend flow loop, a mixing tank and a laser granulometer was set up for studying the kinetics hydrate formation and the pressure is up to 4 MPa. Refrigerant CCl2F2 (R12) hydrate formation experiments were performed using laser light scattering method at 277.1 K and pressures of 0.24 and 0.32 MPa. The liquid flow rates were in the range of 300—1400 L/h. The size distribution and density of R12 hydrate particles in pure water were measured using a laser granulometer. Experimental results show that the size of hydrate particles increases sharply at the initial stage and approaches gradually to a stable size. The hydrate particle concentration in the aqueous phase increases with pressure and circulating liquid flow rate. Based on the material balance, the mathematical model among gas consumption, average hydrate particle size and shading ratio has been established. The calculated results using the mathematical model accord well with the experimental gas consumption data.