This work explores the methodology for micron-scale water droplet contact angle derivation for the warty surface of octocoral sclerites. The calcite-made sclerites of the Red Sea octocoral Dendronephthya hemprichi hav...This work explores the methodology for micron-scale water droplet contact angle derivation for the warty surface of octocoral sclerites. The calcite-made sclerites of the Red Sea octocoral Dendronephthya hemprichi have been chosen as a model for this study. Water droplet condensation on the sclerites has been in-situ investigated using Quanta 200 FEG （field emission gun） ESEM （environmental scanning electron microscope） under wet environmental conditions. Two different analysis methods of droplet top and side views have been applied to determine the contact angle based on the secondary electron images. The ESEM image analysis for the sclerites indicates that their surface is hydrophilic. The microscopic contact angle is measured to be 45.3°±6.3°. The macroscopic contact angle has been calculated by using the Wenzel model for the surface texturing of the sclerites.展开更多
To research techniques for removing the water blocking effect caused by hydraulic applications in coal seams,the use of surfactants is proposed,based on the mechanics of the water blocking effect.Centrifugal experimen...To research techniques for removing the water blocking effect caused by hydraulic applications in coal seams,the use of surfactants is proposed,based on the mechanics of the water blocking effect.Centrifugal experiments were used to validate the effects of using surfactants;the results show that after dealing with vacuum saturation with water,the volume of micropores decreases,which results in a larger average pore size,and the volume of transitional pores,mesopores,macropores and total pores increases.Based on the distribution of pore size,the operation mode of ‘‘water infusion after gas extraction,then continuing gas extraction" is recommended to improve the volume of coal mine gas drainage.When the reflectance of vitrinite in coal samples is less than 1,using the surfactants Fast T,1631,APG,BS can mitigate the damage caused by the water blocking effect.But when the reflectance of vitrinite is larger than 1.4,the damage caused by the water blocking effect can be increased.When the surfactant CMC is used in hydraulic applications,the capillary forces of coal samples are almost negative,which means the capillary force is in the same direction as the gas extraction.The direction of capillary forces benefits the gas flow.So,using CMC can play an active role in removing the water blocking effect.Centrifugal experiments confirm that using CMC can effectively remove the water blocking effect,which has a beneficial effect on improving the gas drainage volume.展开更多
NRL （natural rubber latex） films with 0 （control） and 10 phr sago starch loading were buried in compost soil for 4 weeks. The biodegradation assessments were carried out through films WVT （water vapor transmissio...NRL （natural rubber latex） films with 0 （control） and 10 phr sago starch loading were buried in compost soil for 4 weeks. The biodegradation assessments were carried out through films WVT （water vapor transmission） and mass loss. Scanning electron microscopy was carried out to identify and monitor the properties of rubber degrading organism colonies. Results showed that incorporation of sago starch increased the formation and rates of propagation for microorganism colonies on NRL films with duration of biodegradation. The results also indicate the mechanism of sago starch granules utilization as sole source of energy for microbial growth. The behavior and characteristics of microorganisms involved in NRL films degradation also successfully discussed.展开更多
Objective: To study and compare the hemocompatibility of MWCNTs and hydroxyl modificated MWCNTs (MWCNTs-OH). Methods: MWCNTs and MWCNTs-OH were characterized by scanning electron microscope, Fourier transform infrared...Objective: To study and compare the hemocompatibility of MWCNTs and hydroxyl modificated MWCNTs (MWCNTs-OH). Methods: MWCNTs and MWCNTs-OH were characterized by scanning electron microscope, Fourier transform infrared spectroscopy, water contact angle assays, platelet-adhesion and hemolytic rate assays. Results: The results showed that the two MWCNTs had a similar surface topography and MWCNTs-OH were functionalized with hydroxyl groups on their surfaces. Water contact angle assays indicated that MWCNTs were hydrophobic materials, whereas MWCNTs-OH was hydrophilic. The platelet-adhesion assays displayed that the platelet-adhesion rate of MWCNTs-OH was much lower than MWCNTs. The hemolytic rate assays showed that the hemolytic rates of both MWCNTs were lower than the standard value of 5%. Conclusion: MWCNTs-OH shows superior anticoagulant capacity over MWCNTs. Both MWCNTs and MWCNTs-OH are nonhemolytic materials.展开更多
文摘This work explores the methodology for micron-scale water droplet contact angle derivation for the warty surface of octocoral sclerites. The calcite-made sclerites of the Red Sea octocoral Dendronephthya hemprichi have been chosen as a model for this study. Water droplet condensation on the sclerites has been in-situ investigated using Quanta 200 FEG （field emission gun） ESEM （environmental scanning electron microscope） under wet environmental conditions. Two different analysis methods of droplet top and side views have been applied to determine the contact angle based on the secondary electron images. The ESEM image analysis for the sclerites indicates that their surface is hydrophilic. The microscopic contact angle is measured to be 45.3°±6.3°. The macroscopic contact angle has been calculated by using the Wenzel model for the surface texturing of the sclerites.
基金financially supported by the National Natural Science Foundation of China (No.51504084)the Education Department of Fujian Province (No.JA15493)
文摘To research techniques for removing the water blocking effect caused by hydraulic applications in coal seams,the use of surfactants is proposed,based on the mechanics of the water blocking effect.Centrifugal experiments were used to validate the effects of using surfactants;the results show that after dealing with vacuum saturation with water,the volume of micropores decreases,which results in a larger average pore size,and the volume of transitional pores,mesopores,macropores and total pores increases.Based on the distribution of pore size,the operation mode of ‘‘water infusion after gas extraction,then continuing gas extraction" is recommended to improve the volume of coal mine gas drainage.When the reflectance of vitrinite in coal samples is less than 1,using the surfactants Fast T,1631,APG,BS can mitigate the damage caused by the water blocking effect.But when the reflectance of vitrinite is larger than 1.4,the damage caused by the water blocking effect can be increased.When the surfactant CMC is used in hydraulic applications,the capillary forces of coal samples are almost negative,which means the capillary force is in the same direction as the gas extraction.The direction of capillary forces benefits the gas flow.So,using CMC can play an active role in removing the water blocking effect.Centrifugal experiments confirm that using CMC can effectively remove the water blocking effect,which has a beneficial effect on improving the gas drainage volume.
文摘NRL （natural rubber latex） films with 0 （control） and 10 phr sago starch loading were buried in compost soil for 4 weeks. The biodegradation assessments were carried out through films WVT （water vapor transmission） and mass loss. Scanning electron microscopy was carried out to identify and monitor the properties of rubber degrading organism colonies. Results showed that incorporation of sago starch increased the formation and rates of propagation for microorganism colonies on NRL films with duration of biodegradation. The results also indicate the mechanism of sago starch granules utilization as sole source of energy for microbial growth. The behavior and characteristics of microorganisms involved in NRL films degradation also successfully discussed.
基金National Natural Science Foundation of Chinagrant number:11075116 and 51272176+3 种基金National Basic Research Program of China(973 Program)grant number:2012CB933604Open Research Fund of the State Key Laboratory of Bioelectronics,Southeast Universitythe Key Laboratory of Beam Technology and Material Modification of the Ministry of Education,Beijing Normal University
文摘Objective: To study and compare the hemocompatibility of MWCNTs and hydroxyl modificated MWCNTs (MWCNTs-OH). Methods: MWCNTs and MWCNTs-OH were characterized by scanning electron microscope, Fourier transform infrared spectroscopy, water contact angle assays, platelet-adhesion and hemolytic rate assays. Results: The results showed that the two MWCNTs had a similar surface topography and MWCNTs-OH were functionalized with hydroxyl groups on their surfaces. Water contact angle assays indicated that MWCNTs were hydrophobic materials, whereas MWCNTs-OH was hydrophilic. The platelet-adhesion assays displayed that the platelet-adhesion rate of MWCNTs-OH was much lower than MWCNTs. The hemolytic rate assays showed that the hemolytic rates of both MWCNTs were lower than the standard value of 5%. Conclusion: MWCNTs-OH shows superior anticoagulant capacity over MWCNTs. Both MWCNTs and MWCNTs-OH are nonhemolytic materials.
