A one-step ultrasonic mechanical method was used to synthesize a kind of atmospheric water harvesting material with high water harvesting performance in a wide relative humidity(RH)range,especially at low RH(RH<40%...A one-step ultrasonic mechanical method was used to synthesize a kind of atmospheric water harvesting material with high water harvesting performance in a wide relative humidity(RH)range,especially at low RH(RH<40%),namely,mesoporous silica capsule(MSC)with core-shell structure.Transmission electron microscopy(TEM),nitrogen adsorption and other characterization techniques were used to study the formation process of nano-microspheres.A new mechanism of self-adaptive concentration gradient regulation of silicon migration and recombination core-shell structure was proposed to explain the formation of a cavity in the MSC system.The core-shell design can enhance the specific surface area and pore volume while maintaining the monodispersity and mesoporous size.To study the water harvesting performance of MSC,solid silica nanoparticles(SSN)and mesoporous silica nanoparticles(MSN)were prepared.In a small atmospheric water collection test(25℃,40%RH),the water vapour adsorption and desorption kinetics of MSC,SSN,MSN and a commercial silica gel(CSG)were compared and analyzed.The results show that the MSC with mesoporous channels and core-shell structure can provide about 0.324 gwater/gadsorbent,79%higher than the CSG(0.181 gwater/gadsorbent).It is 25.1%higher than that of 0.259 gwater/gadsorbentof un-hollowed MSN and 980%higher than that of0.03 gwater/gadsorbentof un-hollowed SSN.The material has a large specific surface area and pore volume,simple preparation method and low cost,which provides a feasible idea for realising atmospheric water collection in arid and semi-arid regions.展开更多
Aiming at the problem of available water conservation in desertification ecological restoration, we prepared the water retention materials with montmorillonite（MMT） modified by Castor Oil Polyoxyethylene Ether（10）...Aiming at the problem of available water conservation in desertification ecological restoration, we prepared the water retention materials with montmorillonite（MMT） modified by Castor Oil Polyoxyethylene Ether（10）（EL-10） emulsifying vegetable waxes. The water retention property was studied in simulated desertification climate, and the materials were analyzed and characterized by UV-Vis, SEM, FTIR and XRD measurements. Moreover, a UV carbon arc lamp was used to test the resistance to aging. The experimental results show that the emulsion has good dispersity. Both the water retention property and the aging resistance performance of the modified clay were excellent. The lamellar structure and chemical composition of MMT had no obvious changes before and after modification. The surfaces of clay particles were coated uniformly with modified MMT, so the loose clay particles were cemented together by vegetable waxes. Meanwhile, the original big hydrophilic pores between the clay particles turned into capillary hydrophobic pores. So the clay particles formed a bonding layer which could inhibit water evaporation. Grass-planting experiment showed that reasonable mass ratio of vegetable waxes and EL-10 was 1：18. The materials not only had great water retention property but also maintained sound air permeability so that the germination rate of grass seed significantly increased from 8% to 52%.展开更多
Carbon pillared clay material was prepared from montmorillonite modified by C19H42BrN and C10H16ClN. SEM, FT-IR, XRD, N2 adsorption-desorption, thermal-gravimetric analysis and differential scanning calorimetry were e...Carbon pillared clay material was prepared from montmorillonite modified by C19H42BrN and C10H16ClN. SEM, FT-IR, XRD, N2 adsorption-desorption, thermal-gravimetric analysis and differential scanning calorimetry were employed to characterize the pore structure and test the effect of surfactant. The results show that organic modifier combines with montmorillonite particles by covalent bond and ion embedded. The microstructure of carbon pillared material looks like needle slice. The most probable pore size distribution is about 1.7 nm. The clay material slice mainly consists of two-dimensional aperture supported by a carbonization pillar. The high-temperature stability of carbon pillared clay is im- proved.展开更多
The water-based materials for mine gas absorption and explosion suppression were prepared, in which the mixed organic aggregate of Span80 and alkaline salt can be used as methane absorbent. Methane was used as a model...The water-based materials for mine gas absorption and explosion suppression were prepared, in which the mixed organic aggregate of Span80 and alkaline salt can be used as methane absorbent. Methane was used as a model of mine gas, and the absorptions of methane with different complex materials were studied using head space gas chromatography. Then the state of aqueous material was characterized with laser light scattering instrument and the effects of different complex materials on explosion suppression were preliminarily studied in explosion chamber which can simulate mine gas explosion. The research results showed that complex material could absorb methane and there was some corre- lation between the mean diameter of organic aggregate in aqueous material and the absorption effect. Additionally, the aqueous material could suppress the methane explosion to some degree. The material can absorb mine gas in atomization condition, therefore, degrease mine gas concentration and influence the distribution of mine gas in the space, and then suppress the mine gas explosion to some extent.展开更多
基金the National Natural Science Foundation of China(No.50772131)the National High-tech R&D Program of China(863 Program)(No.2011AA322100)+1 种基金the Key Project of Chinese Ministry of Education(No.106086)the Fundamental Research Funds for the Central Universities(No.2010YJ05)。
文摘A one-step ultrasonic mechanical method was used to synthesize a kind of atmospheric water harvesting material with high water harvesting performance in a wide relative humidity(RH)range,especially at low RH(RH<40%),namely,mesoporous silica capsule(MSC)with core-shell structure.Transmission electron microscopy(TEM),nitrogen adsorption and other characterization techniques were used to study the formation process of nano-microspheres.A new mechanism of self-adaptive concentration gradient regulation of silicon migration and recombination core-shell structure was proposed to explain the formation of a cavity in the MSC system.The core-shell design can enhance the specific surface area and pore volume while maintaining the monodispersity and mesoporous size.To study the water harvesting performance of MSC,solid silica nanoparticles(SSN)and mesoporous silica nanoparticles(MSN)were prepared.In a small atmospheric water collection test(25℃,40%RH),the water vapour adsorption and desorption kinetics of MSC,SSN,MSN and a commercial silica gel(CSG)were compared and analyzed.The results show that the MSC with mesoporous channels and core-shell structure can provide about 0.324 gwater/gadsorbent,79%higher than the CSG(0.181 gwater/gadsorbent).It is 25.1%higher than that of 0.259 gwater/gadsorbentof un-hollowed MSN and 980%higher than that of0.03 gwater/gadsorbentof un-hollowed SSN.The material has a large specific surface area and pore volume,simple preparation method and low cost,which provides a feasible idea for realising atmospheric water collection in arid and semi-arid regions.
基金Funded by the National High-tech Research and Development Program of China(863 Program)(No.2001AA322100)the National Natural Science Foundation of China(No.50772131)+1 种基金the Main Project of Ministry of Education of China(No.106086)the Fundamental Research Funds for the Central Universities of China University of Mining and Technology(Beijing)(No.2012YJ05)
文摘Aiming at the problem of available water conservation in desertification ecological restoration, we prepared the water retention materials with montmorillonite（MMT） modified by Castor Oil Polyoxyethylene Ether（10）（EL-10） emulsifying vegetable waxes. The water retention property was studied in simulated desertification climate, and the materials were analyzed and characterized by UV-Vis, SEM, FTIR and XRD measurements. Moreover, a UV carbon arc lamp was used to test the resistance to aging. The experimental results show that the emulsion has good dispersity. Both the water retention property and the aging resistance performance of the modified clay were excellent. The lamellar structure and chemical composition of MMT had no obvious changes before and after modification. The surfaces of clay particles were coated uniformly with modified MMT, so the loose clay particles were cemented together by vegetable waxes. Meanwhile, the original big hydrophilic pores between the clay particles turned into capillary hydrophobic pores. So the clay particles formed a bonding layer which could inhibit water evaporation. Grass-planting experiment showed that reasonable mass ratio of vegetable waxes and EL-10 was 1：18. The materials not only had great water retention property but also maintained sound air permeability so that the germination rate of grass seed significantly increased from 8% to 52%.
基金Supported by the National High Technology Research and Development Program of China ("863" Project) (Grant No. 2001AA322100)the Main Project of Ministry of Education of China (Grant No. 106086)the Beijing Ceeusro Co-construction Foundation (Grant No. ZH114140537)
文摘Carbon pillared clay material was prepared from montmorillonite modified by C19H42BrN and C10H16ClN. SEM, FT-IR, XRD, N2 adsorption-desorption, thermal-gravimetric analysis and differential scanning calorimetry were employed to characterize the pore structure and test the effect of surfactant. The results show that organic modifier combines with montmorillonite particles by covalent bond and ion embedded. The microstructure of carbon pillared material looks like needle slice. The most probable pore size distribution is about 1.7 nm. The clay material slice mainly consists of two-dimensional aperture supported by a carbonization pillar. The high-temperature stability of carbon pillared clay is im- proved.
文摘The water-based materials for mine gas absorption and explosion suppression were prepared, in which the mixed organic aggregate of Span80 and alkaline salt can be used as methane absorbent. Methane was used as a model of mine gas, and the absorptions of methane with different complex materials were studied using head space gas chromatography. Then the state of aqueous material was characterized with laser light scattering instrument and the effects of different complex materials on explosion suppression were preliminarily studied in explosion chamber which can simulate mine gas explosion. The research results showed that complex material could absorb methane and there was some corre- lation between the mean diameter of organic aggregate in aqueous material and the absorption effect. Additionally, the aqueous material could suppress the methane explosion to some degree. The material can absorb mine gas in atomization condition, therefore, degrease mine gas concentration and influence the distribution of mine gas in the space, and then suppress the mine gas explosion to some extent.
