Plasma membrane vesicles of chrysanthemum ( Dendranthema morifolium (Ramat.) Tzvel.) callus was purified by sucrose gradient centrifugation to investigate the influence of sound stimulation on the lipid physical st...Plasma membrane vesicles of chrysanthemum ( Dendranthema morifolium (Ramat.) Tzvel.) callus was purified by sucrose gradient centrifugation to investigate the influence of sound stimulation on the lipid physical states and metabolism of plasma membrane. The results showed that sound stimulation decreased the content of phosphodiesters and the fluorescent intensity of DPH, but increased the light scattering value of the membrane, the fluorescent intensity of MC540 and the content of phosphomonoesters, indicating that the vesicles got looser, the charge density and hydrophobicity of membrane surface decreased under sound stimulation of some strength and frequency. However, the membrane fluidity increased under the condition. Meanwhile, the anabolism of membrane lipid increased and the catabolism decreased. It can be seen that the physical state and metabolism of membrane lipid is sensitive to sound stimulation.展开更多
Field experiments were carried out to study the effects of plastic film mulching on soil physical characters, including soil temperature, soil moisture content and soil bulk density, and yield and yield components of ...Field experiments were carried out to study the effects of plastic film mulching on soil physical characters, including soil temperature, soil moisture content and soil bulk density, and yield and yield components of sweet potato. The results showed that plastic filming mulching increased soil temperature. Considering the soil temperature-increasing effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. However, with the deepening of soil layer, the warming effect of plastic film mulching was weakened. Black or white plastic film mulching was conducive to low T/R value, especially in the early growth stage of sweet potato. Plastic film mulching significantly improved the storage root yield of sweet potato. In terms of yield-improving effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. The storage root num- ber per plant showed a downward trend, but the weight of single storage root was increased.展开更多
Copolymer of maleic acid and acrylic acid (PMA-100), combining with polyvinyl butyral (PVB) ultrafiltration membrane was used for the removal of Mn(II) from waste water by complexation-ultrafiltration. The carbo...Copolymer of maleic acid and acrylic acid (PMA-100), combining with polyvinyl butyral (PVB) ultrafiltration membrane was used for the removal of Mn(II) from waste water by complexation-ultrafiltration. The carboxylic group content of PMA-100 and the rate of complexation reaction were measured. Effects of the mass ratio of PMA-100 to Mn(II) (n), pH, background electrolyte, etc on the rejection rate (R) and permeate flux (J) were investigated. The results show that carboxylic group content of PMA-100 is 9.5 mmol/g. The complexation of Mn(II) with PMA-100 is rapid and completed within 5 min at pH 6.0. Both R and J increase with pH increasing in the range of 2.5-7.0, and R increases with the increase of n at pH 6.0 while J is little affected. The background electrolyte leads to the decrease of R, and CaCl2 has much greater effect on R than NaCl at the same ionic strength.展开更多
Experiments on treatment of domestic wastewater by membrane bioreactors were carried out.The results showed that this process could produce good quality effluent with low COD,turbidity and total count of bacteria.With...Experiments on treatment of domestic wastewater by membrane bioreactors were carried out.The results showed that this process could produce good quality effluent with low COD,turbidity and total count of bacteria.With intermittent operation and continuous aeration,the membrane flux was kept steady.The mechanisms of removing COD through membrane,the structure of membrane and filtration resistance were also discussed.展开更多
Cell membranes play a crucial role in many biological functions of cells. A small change in the composition of cell membranes can strongly influence the functions of membrane-associated proteins, such as ion and water...Cell membranes play a crucial role in many biological functions of cells. A small change in the composition of cell membranes can strongly influence the functions of membrane-associated proteins, such as ion and water channels, and thus mediate the chemical and physical balance in cells. Such composition change could originate from the introduction of short-chain alcohols, or other anesthetics into membranes. In this work, we have applied sum frequency generation vibrational spectroscopy (SFG-VS), supplemented by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), to investigate interaction between methanol and 1,2-dimyristoyl-d54-sn-glycero-3-phosphocholine (d54-DMPC) lipid bilayers. Lipid's hydrocarbon interior is deuterated while its head group is hydrogenated. At the same time, CH3 symmetric stretch from methanol and lipid head amine group has different frequency, thus we can distinguish the behaviors of methanol, lipid head amine group, and lipid hydrocarbon interior. Based on the spectral feature of the bending mode of the water molecules replaced by methanol, we determined that the methanol molecules are intercalated into the region between amine and phosphate groups at the lipid hydrophilic head. The dipole of CH3 groups of methanol and lipid head, and the water O-H M1 adopt the same orientation directions. The introduction of methanol into the lipid hydrophilic head group can strongly perturb the entire length of the alkyl chains, resulting that the signals of CD2 and CD3 groups from both leaflets can not cancel each other.展开更多
Nitrogen-doped diamond films have been synthesized by EA-CVD (electron assisted chemical vapor deposition) technique. The quality and nitrogen impurity states of the diamond films are characterized by SEM, raman spe...Nitrogen-doped diamond films have been synthesized by EA-CVD (electron assisted chemical vapor deposition) technique. The quality and nitrogen impurity states of the diamond films are characterized by SEM, raman spectroscopy, XPS and EPR speclroscopy, respectively. The results show that the morphology changes from well-defined facets to cauliflower-like structures, the content of amorphous carbon increases and the quality drops with increasing the nitrogen flow rate. Furthermore, in the films, it can be observed that nitrogen impurity exists in the forms ofNs^0, [N-V]^0 and [N-V]^1. The contents of [N-V]^0 and [N-V]^-1 are lower when the nitrogen flow rate is relatively high, and the concentration of Ns^0 varies from 15 ppm to 483 ppm.展开更多
A new type of membrane bioreactor named 'airliftmembrane-bioreactor' is discussed. For municipal wastewaterreclamation, the preliminary study on airlift membrane-bioreactorshows its good performance such as hi...A new type of membrane bioreactor named 'airliftmembrane-bioreactor' is discussed. For municipal wastewaterreclamation, the preliminary study on airlift membrane-bioreactorshows its good performance such as higher flux and lower energyconsumption. The airlift membrane-bioreactor is potentiallyapplicable in bioengineer- ing and environmental protection fields.展开更多
A novel full scale modified A2O (anoxic/anaerobic/aerobic/pre-anoxic)-membrane bioreactor (MBR) plant combined with the step feed strategy was operated to improve the biological nutrient removal (BNR) from low C...A novel full scale modified A2O (anoxic/anaerobic/aerobic/pre-anoxic)-membrane bioreactor (MBR) plant combined with the step feed strategy was operated to improve the biological nutrient removal (BNR) from low C/N ratio municipal wastewater in Southern China. Transformation of organic carbon, nitrogen and phosphorus, and membrane fouling were investigated. Experimental results for over four months demonstrated good efficiencies for chemical oxygen demand (COD) and NH4^+-N removal, with average values higher than 84.5%and 98.1%, re-spectively. A relatively higher total nitrogen (TN) removal efficiency (52.1%) was also obtained at low C/N ratio of 3.82, contributed by the configuration modification (anoxic zone before anaerobic zone) and the step feed with a distribution ratio of 1:1. Addition of sodium acetate into the anoxic zone as the external carbon source, with a theoretical amount of 31.3 mg COD per liter in influent, enhanced denitrification and the TN removal efficiency in-creased to 74.9%. Moreover, the total phosphate (TP) removal efficiency increased by 18.0%. It is suggested that the external carbon source is needed to improve the BNR performance in treating low C/N ratio municipal waste-water in the modified A^2O-MBR process.展开更多
The electro-physical properties of thin layers of rhenium chalcogenides' alloys, their dynamical and static ampere-voltaic characteristics were investigated. During the investigation of static and dynamical ampere-vo...The electro-physical properties of thin layers of rhenium chalcogenides' alloys, their dynamical and static ampere-voltaic characteristics were investigated. During the investigation of static and dynamical ampere-voltaic characteristics of rectifying contact of aluminium and rhenium chalcogenides' alloys the switching effects were found.展开更多
文摘Plasma membrane vesicles of chrysanthemum ( Dendranthema morifolium (Ramat.) Tzvel.) callus was purified by sucrose gradient centrifugation to investigate the influence of sound stimulation on the lipid physical states and metabolism of plasma membrane. The results showed that sound stimulation decreased the content of phosphodiesters and the fluorescent intensity of DPH, but increased the light scattering value of the membrane, the fluorescent intensity of MC540 and the content of phosphomonoesters, indicating that the vesicles got looser, the charge density and hydrophobicity of membrane surface decreased under sound stimulation of some strength and frequency. However, the membrane fluidity increased under the condition. Meanwhile, the anabolism of membrane lipid increased and the catabolism decreased. It can be seen that the physical state and metabolism of membrane lipid is sensitive to sound stimulation.
基金Supported by National Sweet Potato Industrial Technology System(CARS-11-C-16)~~
文摘Field experiments were carried out to study the effects of plastic film mulching on soil physical characters, including soil temperature, soil moisture content and soil bulk density, and yield and yield components of sweet potato. The results showed that plastic filming mulching increased soil temperature. Considering the soil temperature-increasing effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. However, with the deepening of soil layer, the warming effect of plastic film mulching was weakened. Black or white plastic film mulching was conducive to low T/R value, especially in the early growth stage of sweet potato. Plastic film mulching significantly improved the storage root yield of sweet potato. In terms of yield-improving effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. The storage root num- ber per plant showed a downward trend, but the weight of single storage root was increased.
基金Project (21176264) supported by the National Natural Science Foundation of ChinaProject (11JJ2010) supported by Hunan Provincial Natural Science Foundation of ChinaProject (LC13076) supported by Undergraduate Innovation Foundation of Central South University,China
文摘Copolymer of maleic acid and acrylic acid (PMA-100), combining with polyvinyl butyral (PVB) ultrafiltration membrane was used for the removal of Mn(II) from waste water by complexation-ultrafiltration. The carboxylic group content of PMA-100 and the rate of complexation reaction were measured. Effects of the mass ratio of PMA-100 to Mn(II) (n), pH, background electrolyte, etc on the rejection rate (R) and permeate flux (J) were investigated. The results show that carboxylic group content of PMA-100 is 9.5 mmol/g. The complexation of Mn(II) with PMA-100 is rapid and completed within 5 min at pH 6.0. Both R and J increase with pH increasing in the range of 2.5-7.0, and R increases with the increase of n at pH 6.0 while J is little affected. The background electrolyte leads to the decrease of R, and CaCl2 has much greater effect on R than NaCl at the same ionic strength.
基金Supported by the Ministry of Science and Technology of China!(No.96- 92 0 - 0 9- 0 4 )
文摘Experiments on treatment of domestic wastewater by membrane bioreactors were carried out.The results showed that this process could produce good quality effluent with low COD,turbidity and total count of bacteria.With intermittent operation and continuous aeration,the membrane flux was kept steady.The mechanisms of removing COD through membrane,the structure of membrane and filtration resistance were also discussed.
文摘Cell membranes play a crucial role in many biological functions of cells. A small change in the composition of cell membranes can strongly influence the functions of membrane-associated proteins, such as ion and water channels, and thus mediate the chemical and physical balance in cells. Such composition change could originate from the introduction of short-chain alcohols, or other anesthetics into membranes. In this work, we have applied sum frequency generation vibrational spectroscopy (SFG-VS), supplemented by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), to investigate interaction between methanol and 1,2-dimyristoyl-d54-sn-glycero-3-phosphocholine (d54-DMPC) lipid bilayers. Lipid's hydrocarbon interior is deuterated while its head group is hydrogenated. At the same time, CH3 symmetric stretch from methanol and lipid head amine group has different frequency, thus we can distinguish the behaviors of methanol, lipid head amine group, and lipid hydrocarbon interior. Based on the spectral feature of the bending mode of the water molecules replaced by methanol, we determined that the methanol molecules are intercalated into the region between amine and phosphate groups at the lipid hydrophilic head. The dipole of CH3 groups of methanol and lipid head, and the water O-H M1 adopt the same orientation directions. The introduction of methanol into the lipid hydrophilic head group can strongly perturb the entire length of the alkyl chains, resulting that the signals of CD2 and CD3 groups from both leaflets can not cancel each other.
基金the National Natural Science Foundation of China (No.60576011)the Natural Science Foundation of Tianjin (No.06TXTJJC14701,and No.08JCZDJC22700)
文摘Nitrogen-doped diamond films have been synthesized by EA-CVD (electron assisted chemical vapor deposition) technique. The quality and nitrogen impurity states of the diamond films are characterized by SEM, raman spectroscopy, XPS and EPR speclroscopy, respectively. The results show that the morphology changes from well-defined facets to cauliflower-like structures, the content of amorphous carbon increases and the quality drops with increasing the nitrogen flow rate. Furthermore, in the films, it can be observed that nitrogen impurity exists in the forms ofNs^0, [N-V]^0 and [N-V]^1. The contents of [N-V]^0 and [N-V]^-1 are lower when the nitrogen flow rate is relatively high, and the concentration of Ns^0 varies from 15 ppm to 483 ppm.
文摘A new type of membrane bioreactor named 'airliftmembrane-bioreactor' is discussed. For municipal wastewaterreclamation, the preliminary study on airlift membrane-bioreactorshows its good performance such as higher flux and lower energyconsumption. The airlift membrane-bioreactor is potentiallyapplicable in bioengineer- ing and environmental protection fields.
基金Supported by the National Water Pollution Control and Management(2008ZX07316-002)the University of Macao Research Committee(RG067/09-10S/SHJ/FST)
文摘A novel full scale modified A2O (anoxic/anaerobic/aerobic/pre-anoxic)-membrane bioreactor (MBR) plant combined with the step feed strategy was operated to improve the biological nutrient removal (BNR) from low C/N ratio municipal wastewater in Southern China. Transformation of organic carbon, nitrogen and phosphorus, and membrane fouling were investigated. Experimental results for over four months demonstrated good efficiencies for chemical oxygen demand (COD) and NH4^+-N removal, with average values higher than 84.5%and 98.1%, re-spectively. A relatively higher total nitrogen (TN) removal efficiency (52.1%) was also obtained at low C/N ratio of 3.82, contributed by the configuration modification (anoxic zone before anaerobic zone) and the step feed with a distribution ratio of 1:1. Addition of sodium acetate into the anoxic zone as the external carbon source, with a theoretical amount of 31.3 mg COD per liter in influent, enhanced denitrification and the TN removal efficiency in-creased to 74.9%. Moreover, the total phosphate (TP) removal efficiency increased by 18.0%. It is suggested that the external carbon source is needed to improve the BNR performance in treating low C/N ratio municipal waste-water in the modified A^2O-MBR process.
文摘The electro-physical properties of thin layers of rhenium chalcogenides' alloys, their dynamical and static ampere-voltaic characteristics were investigated. During the investigation of static and dynamical ampere-voltaic characteristics of rectifying contact of aluminium and rhenium chalcogenides' alloys the switching effects were found.