Hydrogen evolution reaction(HER)and urea oxidation reaction(UOR)are key reactions of the watercycling associated catalytic process/device.The design of catalysts with a super-hydrophilic/aerophobic structure and optim...Hydrogen evolution reaction(HER)and urea oxidation reaction(UOR)are key reactions of the watercycling associated catalytic process/device.The design of catalysts with a super-hydrophilic/aerophobic structure and optimized electron distribution holds great promise.Here,we have designed a threedimensional(3D)hollow Ni/NiMoN hierarchical structure with arrayed-sheet surface based on a onepot hydrothermal route for efficient urea-assisted HER based on a simple hydrothermal process.The Ni/NiMoN catalyst exhibits super-hydrophilic/aerophobic properties with a small droplet contact angle of 6.07°and an underwater bubble contact angle of 155.7°,thus facilitating an escape of bubbles from the electrodes.Density functional theory calculations and X-ray photoelectron spectroscopy results indicate the optimized electronic structure at the interface of Ni and NiMoN,which can promote the adsorption/desorption of reactants and intermediates.The virtues combining with a large specific surface area endow Ni/NiMoN with efficient catalytic activity of low potentials of 25 mV for HER and 1.33 V for UOR at10 mA cm^(-2).The coupled HER and UOR system demonstrates a low cell voltage of 1.42 V at 10 mA cm^(-2),which is approximately 209 mV lower than water electrolysis.展开更多
Thick electrodes can substantially enhance the overall energy density of batteries.However,insufficient wettability of aqueous electrolytes toward electrodes with conventional hydrophobic binders severely limits utili...Thick electrodes can substantially enhance the overall energy density of batteries.However,insufficient wettability of aqueous electrolytes toward electrodes with conventional hydrophobic binders severely limits utilization of active materials with increasing the thickness of electrodes for aqueous batteries,resulting in battery performance deterioration with a reduced capacity.Here,we demonstrate that controlling the hydrophilicity of the thicker electrodes is critical to enhancing the overall energy density of batteries.Hydrophilic binders are synthesized via a simple sulfonation process of conventional polyvinylidene fluoride binders,considering physicochemical properties such as mechanical properties and adhesion.The introduction of abundant sulfonate groups of binders(i)allows fast and sufficient electrolyte wetting,and(ii)improves ionic conduction in thick electrodes,enabling a significant increase in reversible capacities under various current densities.Further,the sulfonated binder effectively inhibits the dissolution of cathode materials in reactive aqueous electrolytes.Overall,our findings significantly enhance the energy density and contribute to the development of practical zinc-ion batteries.展开更多
The Nd-doped TiO2 thin films with higher hydrophilic and photocatalytic activities were prepared on glass slides by an acid-catalyzed sol?gel method. The effects of Nd doping on crystalline phase, surface composition...The Nd-doped TiO2 thin films with higher hydrophilic and photocatalytic activities were prepared on glass slides by an acid-catalyzed sol?gel method. The effects of Nd doping on crystalline phase, surface composition and optical property were investigated by means of techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), optical contact angle tester and UV-Vis spectroscopy. The results show that Nd doping obviously influences the hydrophilic and photocatalytic activities of TiO2thin films. Nd doping could cause the TiO2 lattice distortion, inhibit phase transition from anatase to rutile, cause red shift of the absorption spectrum edge, produce hydroxyl radicals (·OH), and accelerate surface hydroxylation, which result in a significant improvement in the hydrophilicity and photoreactivity of Nd-doped TiO2 thin films. When the content of Nd is 0.1% (mass fraction), TiO2 thin films achieve the smallest grain size (about 15 nm), and the hydrophilic and photocatalytic activities of TiO2 thin film reach the maximum, the contact angle is only 8.1°, and 92% of methylene blue is finally degraded. Moreover, the modification mechanism of Nd doping was also discussed.展开更多
Ta-containing TiO2 films with Ta contents of 5%, 20%, 33% (mole fraction) were sol-gel coated on the surface roughened Ti6AI4V alloy by dip coating method for biomedical applications. The Ta-TiO2 films on 1.5 mol/L ...Ta-containing TiO2 films with Ta contents of 5%, 20%, 33% (mole fraction) were sol-gel coated on the surface roughened Ti6AI4V alloy by dip coating method for biomedical applications. The Ta-TiO2 films on 1.5 mol/L NaOH-HCI pretreated substrate are adherent, but there are cracks for the sample with 33% Ta. X-ray photoelectron spectroscopy results show that Ti and Ta exist as TiP2 and Ta205 in the film, and A1 element is not detectable. X-ray diffraction and Raman scattering analyses reveal that the addition of Ta decreases crystallization of the films. Potentiodynamic polarization test in a Ca-free Hank's balanced solution demonstrates that the coating samples markedly improve the corrosion resistance compared with the polished sample. The addition of Ta impedes UV light-induced hydrophilic conversion of the coating samples. The sample with 20% Ta has enough film integrity and hydrophilic conversion rate, and is expected to possess good biological properties.展开更多
Porous polyvinylidene fluoride(PVDF)membranes blended with LiCl are prepared through the phase inversion method to obtain a good support layer for air dehumidification.The hydrophilicity of the resulting membrane is...Porous polyvinylidene fluoride(PVDF)membranes blended with LiCl are prepared through the phase inversion method to obtain a good support layer for air dehumidification.The hydrophilicity of the resulting membrane is evaluated by water contact angle measurements and vapor adsorption tests.The moisture permeation performance of the membrane is measured by permeation tests in terms of total mass transfer coefficients and moisture permeability rates.It is found that water contact angles and water vapor adsorption capacities increase with the increasing LiCl content in the casting solution.As the LiCl content increases,the total mass transfer coefficient increases slightly at a low LiCl content(below 2.5%)and then improves greatly at a high LiCl content(above 2.5%),whereas the moisture permeation rate increases.The results demonstrate that LiCl can remarkably improve the hydrophilicity of PVDF membranes,and then greatly enhance moisture permeation performance.展开更多
Invasion of drilling fluid into natural gas hydrate deposits during drilling might damage the reservoir,induce hydrate dissociation and then cause wellbore instability and distortion of the data from well logging. Add...Invasion of drilling fluid into natural gas hydrate deposits during drilling might damage the reservoir,induce hydrate dissociation and then cause wellbore instability and distortion of the data from well logging. Adding nanoparticles into drilling fluid is an effective method in reducing the invasion of drilling fluid and enhancing borehole stability. However, the addition of nanoparticles might also introduce hydrate formation risk in borehole because they can act as the "seeds" for hydrate nucleation. This paper presents an experimental study of the effect of hydrophilic silica nanoparticle on gas hydrate formation in a dynamic methane/liquid-water system. In the experiment, the ultrapure water with and without1.0 wt%–6.0 wt% concentrations of silica nanoparticles, grain sizes of 20 and 50 nm, were pressurized by methane gas under varied conditions of temperature and pressure. The induction time, the gas consumption, and the average rate of gas consumption in the system were measured and compared to those in ultrapure water. The results show that a concentration of 4.0 wt% hydrophilic SiO_2 particles with a grain size of 50 nm has a relatively strong inhibition effect on hydrate formation when the initial experimental condition is 5.0 °C and 5.0 MPa. Compared to ultrapure water, the hydrophilic nano-SiO_2 fluid increases the induction time for hydrate formation by 194% and decreases the amount and average rate of hydrate formation by 10% and 17%, respectively. This inhibition effect may be attributed to the hydrophilicity,amount and aggregation of silica nanoparticle according to the results of water activity and zeta potential measurements. Our work also elucidates hydrophilic, instead of hydrophobic, nanoparticles can be added to the drilling fluid to maintain wellbore stability and to protect the hydrate reservoir from drilling mud damage, because they exhibit certain degree of hydrate inhibition which can reduce the risk of hydrate reformation and aggregation during gas hydrate or deep water drilling if their concentration can be controlled properly.展开更多
AIM:To evaluate the rotational stability and visual outcomes of a single-piece hydrophilic acrylic toric intraocular lenses(IOL) over a 1.5-year follow-up period.Data from the 6-month follow-up study have been prev...AIM:To evaluate the rotational stability and visual outcomes of a single-piece hydrophilic acrylic toric intraocular lenses(IOL) over a 1.5-year follow-up period.Data from the 6-month follow-up study have been previously reported.METHODS:Forty eyes of 26 cataract patients(mean age:72.8±7.9y) with pre-existing corneal astigmatism of 1.0 to 2.6 D were enrolled in the study.Mean axial length was 23.17±0.88 mm.Main outcome measures after implantation of the Torica-a A IOL(Human Optics) were IOL rotational stability,subjective refraction,astigmatism correction,uncorrected and corrected distance visual acuity(UDVA,CDVA).RESULTS:There was no significant change in the parameters evaluated between the 6-month and 1.5-year follow-ups.At last visit,mean absolute IOL rotation(objective method) was 1.81°±1.87°(range 0.00° to 7.20°) with 78.6% of eyes having IOL rotation 〈3°,92.9% of eyes 〈5° and 100% of eyes 〈8°.No patient required secondary IOL repositioning during the course of the study.Mean residual refractive cylinder was-0.60±0.40 D.There was a significant reduction in the magnitude of the J0 vector postoperatively(P〈0.0001) with a mean absolute change of 0.76±0.40 D.The mean J45 vector was close to zero preoperatively and postoperatively and didn't change significantly(P=0.28).Mean monocular UDVA and CDVA was 0.09±0.12 log MAR and-0.01±0.12 log MAR,respectively.No treatment with Nd:YAG laser was required.CONCLUSION:The Torica-a A IOL shows good and stable visual performance and rotational stability over a 1.5-year follow-up period.展开更多
Six groups of segmented polyurethanes with amorphous soft segment domains based on mixed hydrophobic polyester and hydrophilic polyether soft monomers were prepared from 4, 4′ diphenylmethane diisocyanate (MDI), po...Six groups of segmented polyurethanes with amorphous soft segment domains based on mixed hydrophobic polyester and hydrophilic polyether soft monomers were prepared from 4, 4′ diphenylmethane diisocyanate (MDI), polybutylene adipate glycol 2000 (PBA2000), polytetramethylene glycol 1000 (PTMG1000) and polyethylene glycol 1000 (PEG1000) with 1,4-butanediol (BDO) as the chain extender. Furthermore, the representative properties of the hydrophilic polyurethanes, moisture permeability and water resistance, were investigated. The results show that the chemical structure, molecular weight and concentration of soft monomers have remarkable effects on the main application properties of hydrophilic polyurethane. The important factors in diffusion are the content of hydrophilic ether bond and the mobility of hydrophilic chain in the soft phase, which is represented with a good approximation by the average mean molecular weight of soft segment. On the contrary, the functional properties of the hydrophilic polyurethane are almost not affected by its hard segment.展开更多
Copolymerization of chitosan selectively grafted by polyethylene glycol was prepared. Chitosan was selectively grafted by monomethoxy polyethylene glycol(mPEG-OH), which contained a hydroxyl group combining with hex...Copolymerization of chitosan selectively grafted by polyethylene glycol was prepared. Chitosan was selectively grafted by monomethoxy polyethylene glycol(mPEG-OH), which contained a hydroxyl group combining with hexamethylene diisocyanate(HDI) to form a novel macromonomer namely monomethoxy polyethylene glycol isocyanate(mPEG-NCO) containing a isocyanate group with higher chemical activity in ethyl glyoxalate solution absolutely without water. The selective grafted copolymerization of Chitosan with mPEG-NCO was conducted under heterogeneous conditions as suspension in dimethylformamide. The hydrophilic copolymers of chitosan were prepared by condensation reaction of isocyanate group on mPEG- NCO with hydroxy groups on chitosan chains because amino groups on chitosan chains were protected by complexion formation with copper ions. The effect of reaction condition on the grafting extents was discussed. Swelling properties of mPEG-g-CS were researched. The graft copolymer mPEG-g-CS was characterized by the infrared spectra. The experimental result showed that the copper ions were very effective to protect amino groups from condensation reaction. The swelling degree in water increases with adding of grafting ratio. The maximum swelling degree was up to above 132% when the grafting ratio was about 270%. The graft copolymer can be soluble partially in pure water.展开更多
To solve the so called “white rust” and ’water bridge" problems of the aluminum fins for heat exchanger of automobile air conditioner, aimed at nationalizing the art of hydrophilic coating technology, the choi...To solve the so called “white rust” and ’water bridge" problems of the aluminum fins for heat exchanger of automobile air conditioner, aimed at nationalizing the art of hydrophilic coating technology, the choice of coating forming and curing materials was investigated. By measuring the water contact angle, SEM surface scanning and ingredients analysis of the coating, optimal parameters and composition are acquired. The coating forming mechanisms of the composition was also expatiated. The coating obtained has good hydrophilic and other properties.展开更多
·AIM: To compare posterior capsule opacification(PCO)degree and visual functions after phacoemulsification in eyes implanted with 360-degree square edge hydrophilic acrylic intraocular lens(IOL)(570C C-flex, Rayn...·AIM: To compare posterior capsule opacification(PCO)degree and visual functions after phacoemulsification in eyes implanted with 360-degree square edge hydrophilic acrylic intraocular lens(IOL)(570C C-flex, Rayner) and sharp edge hydrophobic acrylic IOL(Sensar AR40 e,AMO) in diabetic patients.· METHODS: Sixty diabetic patients underwent uneventful phacoemulsification and randomly implanted one of the two IOLs. The PCO value was measured by retroillumination photographs and Evaluation of Posterior Capsule Opacification(EPCO) 2000 image-analysis software at 1, 6, 12, and 24 mo after surgery. Visual acuity, and contrast sensitivity in photopic and mesopic conditions were also examined at each follow up time point. The incidence of eye that required Nd:YAG laser posterior capsulotomy were also compared.·RESULTS: There was not any statistically significant difference in PCO scores between Rayner C-flex 570 C group and Sensar AR40 e group at each follow up time point. Visual acuity, Nd:YAG capsulotomy incidence and contrast sensitivity also had no significant difference during the 24 mo follow-up.·CONCLUSION: For diabetic patients, Rayner 570 C Cflex and Sensar AR40 e IOLs are same effective for prevent PCO. The 360-degree square edge design maybe is a good alternative technique to improve PCO prevention.展开更多
Three different low-temperature plasma-based methods were used to improve the surface hydrophilicity of polyethy- lene (PE) films, and all the modification processes were carried out by employing an atmospheric pres...Three different low-temperature plasma-based methods were used to improve the surface hydrophilicity of polyethy- lene (PE) films, and all the modification processes were carried out by employing an atmospheric pressure plasma jet (APPJ) system. (a) PE films were directly modified by APPJ using a gas mixture of He and 02. (b) Acrylic acid (AA) was introduced into the system and a polymer acrylic acid (PAA) coating was deposited onto the PE films. (c) AA was grafted onto the PE surface activated by plasma pre-treatment. It was found that the hydrophilicity of the PE films was significantly improved for all the three methods. However, the samples modified by Process (a) showed hydrophobicity recovery after a storage time of 20 days while no significant change was found in samples modified by Process (b) and Process (c). The Fourier transform infrared spectroscopy (FTIR) results indicated that the most intensive C=O peak was detected on the PE surface modified by Process (c). According to the X-ray photoelectron spectroscopy (XPS) analysis, the ratios of oxygen-containing polar groups for samples modified by Process (b) and Process (c) were higher than that modified by Process (a).展开更多
Hydrophilic ceramic membranes would be potential candidates for membrane gas absorption if they could be applied to appropriate separation processes.This study highlights a novel concept for the practical implementati...Hydrophilic ceramic membranes would be potential candidates for membrane gas absorption if they could be applied to appropriate separation processes.This study highlights a novel concept for the practical implementation of SO_2 absorption in hydrophilic ceramic membrane that exhibits outstanding thermal and mechanical stabilities.With this aim,we investigated experimentally the performance of SO_2 absorption into aqueous sodium hydroxide (NaOH) solution in a hydrophilic alumina (Al_2O_3) membrane contactor in terms of SO_2 removal efficiency and SO_2 mass transfer flux,and compared the performance with that in a hydrophobic one.A series of experiments were performed at various conditions over a NaOH concentration range of 0–1.0 mol·L^(-1),a liquid flow rate range of 30–180 ml·min^(-1),a gas flow rate range of 120–1000 ml·min^(-1),an inlet SO_2 concentration range of 400–2000μl·L^(-1),and a temperature range of 10–35°C.It was found that the hydrophilic membrane was more competitive when using a NaOH concentration higher than 0.2 mol·L^(-1).Furthermore,it can be inferred that the hydrophilicα-Al_2O_3 membrane exhibited exceptional long-term stability under 480 h continuous operation.展开更多
A new Fenton-like system in a medium of hydrophilic triethylammonium type of ionic liquid(IL) was used for the hydroxylation of benzene to phenol. The triethylammonium acetate([Et3NH][CH3COO]) IL exhibited retarda...A new Fenton-like system in a medium of hydrophilic triethylammonium type of ionic liquid(IL) was used for the hydroxylation of benzene to phenol. The triethylammonium acetate([Et3NH][CH3COO]) IL exhibited retardation performance for the decomposition of H2O2 and protection performance for the further oxidation of phenol, thus the yield and selectivity to phenol were promoted greatly. The acidity of the system was proved to be an important factor for the selectivity to phenol. The utilization of H2O2 and the selectivity to phenol, as well as the Turnover number(TON) of the catalyst were effectively enhanced by a benzene-[Et3NH][CH3COO] bi-phase system. The catalyst with [Et3NH][CH3COO] IL was recycled with stable catalytic performance.展开更多
A novel technology of preparation of felt-metal supported modified polyvinyl alcohol(PVA) ultrafiltration(UF) membrane was invented, which could avoid the blockage of the holes of support layer and the leakage of ...A novel technology of preparation of felt-metal supported modified polyvinyl alcohol(PVA) ultrafiltration(UF) membrane was invented, which could avoid the blockage of the holes of support layer and the leakage of the casting solution through the holes of support layer. Felt-metal supported ferric sulfate modified PVA composite UF membranes were prepared by the innovative technology. The results show that the composite membranes are used to treat 1 000 mg/L oil/water emulsion at trans-membrane pressure from 0.25 to 0.45 MPa, the permeate flux is from 36 to 52 L/(m2·h), and the retention of chemical oxygen demand(COD) is over 92%. The composite membrane resistance increases with the increase of trans-naembrane pressure.展开更多
The processing of an energy carrier such as microalgae oil into valuable fuels and chemicals is quite promising.Aqueous-phase processing is suitable for this purpose because the separation of intrinsic water from the ...The processing of an energy carrier such as microalgae oil into valuable fuels and chemicals is quite promising.Aqueous-phase processing is suitable for this purpose because the separation of intrinsic water from the algae cell is difficult.In this study,we synthesized ruthenium(Ru)nanoparticles supported on highly hydrophilic mesoporous carbon to catalyze the quantitative hydrodeoxygenation(HDO)of microalgae oil to alkanes in a one-pot process at a low temperature(140℃)in the aqueous phase.The mesoporous carbon was obtained by single-step calcination of starch and zinc chloride in nitrogen.The as-obtained carbon showed high surface areas and pore volumes,allowing high dispersion of Ru nanoparticles.The surface of the carbon material was rich in hydroxyl groups,as evidenced by X-ray photoelectron spectroscopy(XPS),infrared(IR)spectroscopy,and thermogravimetric analysis(TGA)measurements.As a result,the carbon material contacted preferably with the water phase versus the organic phase,improving the accessibility of substrates.On the other hand,the contact angle test results speculated the superior hydrophilic nature of mesoporous Ru/C(ZnCl2,starch)than commercial Ru/C.Both kinetics modeling and in situ IR monitoring in water revealed the superior performance of the hydrophilic mesoporous and hydrophilic Ru/C compared to a commercial Ru/C for the tandem hydrogenation of stearic acid and decarbonylation of stearyl alcohol.The herein designed hydrothermal carbon material was highly active,environmentally benign,sustainable,and recyclable material,and could be potentially used for other hydrogenation reactions in the aqueous phase.展开更多
Novel double hydrophilic block copolymers with amine pendant chains were synthesized by polymerization of 4-vinyl benzylamine hydrochloric salt using 4,4′-azo-bis[4-cyanopentanoate poly(ethylene glycol) ester] as m...Novel double hydrophilic block copolymers with amine pendant chains were synthesized by polymerization of 4-vinyl benzylamine hydrochloric salt using 4,4′-azo-bis[4-cyanopentanoate poly(ethylene glycol) ester] as macroazoinitiator. The structures of the copolymers were characterized by ^1H NMR, FTIR spectra and acid-base titration, GPC-MALS techniques.展开更多
TiO2-SiO2 thin films have been prepared on slide glass substrates by sol-gel method, and the effect of SiO2 additive on photo-generated hydrophilicity of TiO2 thin film was investigated by measuring the contact angle ...TiO2-SiO2 thin films have been prepared on slide glass substrates by sol-gel method, and the effect of SiO2 additive on photo-generated hydrophilicity of TiO2 thin film was investigated by measuring the contact angle of water, the microstructure, the transmittance, the photocatalytic activity and the specific surface area . The results showed that 10mol% of SiO2 additive was the most effective for decreasing contact angle of water. The SiO2 additive of less than 30mol% has a suppressive effect on the crystal growth of anatase in calcinations, resulting in a large surface area. Consequently, the super-hydrophilicity was improved.展开更多
基金financially supported by the National Key R&D Program of China(2022YFA1503003)the National Natural Science Foundation of China(91961111,22271081)+3 种基金the Natural Science Foundation of Heilongjiang Province(ZD2021B003)the University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province(UNPYSCT-2020004)The Basic Research Fund of Heilongjiang University in Heilongjiang Province(2021-KYYWF-0039)the Heilongjiang University Excellent Youth Foundation。
文摘Hydrogen evolution reaction(HER)and urea oxidation reaction(UOR)are key reactions of the watercycling associated catalytic process/device.The design of catalysts with a super-hydrophilic/aerophobic structure and optimized electron distribution holds great promise.Here,we have designed a threedimensional(3D)hollow Ni/NiMoN hierarchical structure with arrayed-sheet surface based on a onepot hydrothermal route for efficient urea-assisted HER based on a simple hydrothermal process.The Ni/NiMoN catalyst exhibits super-hydrophilic/aerophobic properties with a small droplet contact angle of 6.07°and an underwater bubble contact angle of 155.7°,thus facilitating an escape of bubbles from the electrodes.Density functional theory calculations and X-ray photoelectron spectroscopy results indicate the optimized electronic structure at the interface of Ni and NiMoN,which can promote the adsorption/desorption of reactants and intermediates.The virtues combining with a large specific surface area endow Ni/NiMoN with efficient catalytic activity of low potentials of 25 mV for HER and 1.33 V for UOR at10 mA cm^(-2).The coupled HER and UOR system demonstrates a low cell voltage of 1.42 V at 10 mA cm^(-2),which is approximately 209 mV lower than water electrolysis.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2022R1F1A1070168,2020R1C1C1004322)the Korea Institute of Industrial Technology as Development of core technology for smart wellness care based on cleaner production process technology(KITECH-PEH23030)+1 种基金supported by the Renewable Surplus Sector Coupling Technology Program of the Korea Institute of Energy Technology Evaluation and Planning(KETEP)granted financial resource from the Ministry of Trade,Industry&Energy,Republic of Korea(No.20226210100050)the National Research Council of Science&Technology(NST)grant by the Korea government(MSIT)(No.CPS21141-100)。
文摘Thick electrodes can substantially enhance the overall energy density of batteries.However,insufficient wettability of aqueous electrolytes toward electrodes with conventional hydrophobic binders severely limits utilization of active materials with increasing the thickness of electrodes for aqueous batteries,resulting in battery performance deterioration with a reduced capacity.Here,we demonstrate that controlling the hydrophilicity of the thicker electrodes is critical to enhancing the overall energy density of batteries.Hydrophilic binders are synthesized via a simple sulfonation process of conventional polyvinylidene fluoride binders,considering physicochemical properties such as mechanical properties and adhesion.The introduction of abundant sulfonate groups of binders(i)allows fast and sufficient electrolyte wetting,and(ii)improves ionic conduction in thick electrodes,enabling a significant increase in reversible capacities under various current densities.Further,the sulfonated binder effectively inhibits the dissolution of cathode materials in reactive aqueous electrolytes.Overall,our findings significantly enhance the energy density and contribute to the development of practical zinc-ion batteries.
基金Projects(51162022,21201098)supported by the National Natural Science Foundation of ChinaProject(GJJ14126)supported by Jiangxi Provincial Education Department,ChinaProject(2012019)supported by the Test Foundation of Nanchang University,China
文摘The Nd-doped TiO2 thin films with higher hydrophilic and photocatalytic activities were prepared on glass slides by an acid-catalyzed sol?gel method. The effects of Nd doping on crystalline phase, surface composition and optical property were investigated by means of techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), optical contact angle tester and UV-Vis spectroscopy. The results show that Nd doping obviously influences the hydrophilic and photocatalytic activities of TiO2thin films. Nd doping could cause the TiO2 lattice distortion, inhibit phase transition from anatase to rutile, cause red shift of the absorption spectrum edge, produce hydroxyl radicals (·OH), and accelerate surface hydroxylation, which result in a significant improvement in the hydrophilicity and photoreactivity of Nd-doped TiO2 thin films. When the content of Nd is 0.1% (mass fraction), TiO2 thin films achieve the smallest grain size (about 15 nm), and the hydrophilic and photocatalytic activities of TiO2 thin film reach the maximum, the contact angle is only 8.1°, and 92% of methylene blue is finally degraded. Moreover, the modification mechanism of Nd doping was also discussed.
基金Project(xjj2011096)supported by the Fundamental Research Fund for the Central Universities,ChinaProjects(50901058,51374174)supported by the National Natural Science Foundation of China
文摘Ta-containing TiO2 films with Ta contents of 5%, 20%, 33% (mole fraction) were sol-gel coated on the surface roughened Ti6AI4V alloy by dip coating method for biomedical applications. The Ta-TiO2 films on 1.5 mol/L NaOH-HCI pretreated substrate are adherent, but there are cracks for the sample with 33% Ta. X-ray photoelectron spectroscopy results show that Ti and Ta exist as TiP2 and Ta205 in the film, and A1 element is not detectable. X-ray diffraction and Raman scattering analyses reveal that the addition of Ta decreases crystallization of the films. Potentiodynamic polarization test in a Ca-free Hank's balanced solution demonstrates that the coating samples markedly improve the corrosion resistance compared with the polished sample. The addition of Ta impedes UV light-induced hydrophilic conversion of the coating samples. The sample with 20% Ta has enough film integrity and hydrophilic conversion rate, and is expected to possess good biological properties.
基金The National Natural Science Foundation of China(No.50676034)the National High Technology Research and Development Program of China(863 Program)(No.2008AA05Z206)
文摘Porous polyvinylidene fluoride(PVDF)membranes blended with LiCl are prepared through the phase inversion method to obtain a good support layer for air dehumidification.The hydrophilicity of the resulting membrane is evaluated by water contact angle measurements and vapor adsorption tests.The moisture permeation performance of the membrane is measured by permeation tests in terms of total mass transfer coefficients and moisture permeability rates.It is found that water contact angles and water vapor adsorption capacities increase with the increasing LiCl content in the casting solution.As the LiCl content increases,the total mass transfer coefficient increases slightly at a low LiCl content(below 2.5%)and then improves greatly at a high LiCl content(above 2.5%),whereas the moisture permeation rate increases.The results demonstrate that LiCl can remarkably improve the hydrophilicity of PVDF membranes,and then greatly enhance moisture permeation performance.
基金supported by National Youth Top-notch Talent Support Programthe National Natural Science Foundationof China(41672367,51704266)+2 种基金China Geological Survey Project(DD20160216)Qingdao National Laboratory for Marine Science and Technology Open Fund(QNLM2016ORP0203)Experimental Apparatus Improvement Program of CUG(SJ-201613)
文摘Invasion of drilling fluid into natural gas hydrate deposits during drilling might damage the reservoir,induce hydrate dissociation and then cause wellbore instability and distortion of the data from well logging. Adding nanoparticles into drilling fluid is an effective method in reducing the invasion of drilling fluid and enhancing borehole stability. However, the addition of nanoparticles might also introduce hydrate formation risk in borehole because they can act as the "seeds" for hydrate nucleation. This paper presents an experimental study of the effect of hydrophilic silica nanoparticle on gas hydrate formation in a dynamic methane/liquid-water system. In the experiment, the ultrapure water with and without1.0 wt%–6.0 wt% concentrations of silica nanoparticles, grain sizes of 20 and 50 nm, were pressurized by methane gas under varied conditions of temperature and pressure. The induction time, the gas consumption, and the average rate of gas consumption in the system were measured and compared to those in ultrapure water. The results show that a concentration of 4.0 wt% hydrophilic SiO_2 particles with a grain size of 50 nm has a relatively strong inhibition effect on hydrate formation when the initial experimental condition is 5.0 °C and 5.0 MPa. Compared to ultrapure water, the hydrophilic nano-SiO_2 fluid increases the induction time for hydrate formation by 194% and decreases the amount and average rate of hydrate formation by 10% and 17%, respectively. This inhibition effect may be attributed to the hydrophilicity,amount and aggregation of silica nanoparticle according to the results of water activity and zeta potential measurements. Our work also elucidates hydrophilic, instead of hydrophobic, nanoparticles can be added to the drilling fluid to maintain wellbore stability and to protect the hydrate reservoir from drilling mud damage, because they exhibit certain degree of hydrate inhibition which can reduce the risk of hydrate reformation and aggregation during gas hydrate or deep water drilling if their concentration can be controlled properly.
文摘AIM:To evaluate the rotational stability and visual outcomes of a single-piece hydrophilic acrylic toric intraocular lenses(IOL) over a 1.5-year follow-up period.Data from the 6-month follow-up study have been previously reported.METHODS:Forty eyes of 26 cataract patients(mean age:72.8±7.9y) with pre-existing corneal astigmatism of 1.0 to 2.6 D were enrolled in the study.Mean axial length was 23.17±0.88 mm.Main outcome measures after implantation of the Torica-a A IOL(Human Optics) were IOL rotational stability,subjective refraction,astigmatism correction,uncorrected and corrected distance visual acuity(UDVA,CDVA).RESULTS:There was no significant change in the parameters evaluated between the 6-month and 1.5-year follow-ups.At last visit,mean absolute IOL rotation(objective method) was 1.81°±1.87°(range 0.00° to 7.20°) with 78.6% of eyes having IOL rotation 〈3°,92.9% of eyes 〈5° and 100% of eyes 〈8°.No patient required secondary IOL repositioning during the course of the study.Mean residual refractive cylinder was-0.60±0.40 D.There was a significant reduction in the magnitude of the J0 vector postoperatively(P〈0.0001) with a mean absolute change of 0.76±0.40 D.The mean J45 vector was close to zero preoperatively and postoperatively and didn't change significantly(P=0.28).Mean monocular UDVA and CDVA was 0.09±0.12 log MAR and-0.01±0.12 log MAR,respectively.No treatment with Nd:YAG laser was required.CONCLUSION:The Torica-a A IOL shows good and stable visual performance and rotational stability over a 1.5-year follow-up period.
基金Funded by the Key Natural Science Foundation of Shaanxi Province Education Department (No.04JK-181)the Direction Program of China Textile Industry Association (No.2007-049)
文摘Six groups of segmented polyurethanes with amorphous soft segment domains based on mixed hydrophobic polyester and hydrophilic polyether soft monomers were prepared from 4, 4′ diphenylmethane diisocyanate (MDI), polybutylene adipate glycol 2000 (PBA2000), polytetramethylene glycol 1000 (PTMG1000) and polyethylene glycol 1000 (PEG1000) with 1,4-butanediol (BDO) as the chain extender. Furthermore, the representative properties of the hydrophilic polyurethanes, moisture permeability and water resistance, were investigated. The results show that the chemical structure, molecular weight and concentration of soft monomers have remarkable effects on the main application properties of hydrophilic polyurethane. The important factors in diffusion are the content of hydrophilic ether bond and the mobility of hydrophilic chain in the soft phase, which is represented with a good approximation by the average mean molecular weight of soft segment. On the contrary, the functional properties of the hydrophilic polyurethane are almost not affected by its hard segment.
基金Funded by the Program of Beijing Municipal Commission of Education
文摘Copolymerization of chitosan selectively grafted by polyethylene glycol was prepared. Chitosan was selectively grafted by monomethoxy polyethylene glycol(mPEG-OH), which contained a hydroxyl group combining with hexamethylene diisocyanate(HDI) to form a novel macromonomer namely monomethoxy polyethylene glycol isocyanate(mPEG-NCO) containing a isocyanate group with higher chemical activity in ethyl glyoxalate solution absolutely without water. The selective grafted copolymerization of Chitosan with mPEG-NCO was conducted under heterogeneous conditions as suspension in dimethylformamide. The hydrophilic copolymers of chitosan were prepared by condensation reaction of isocyanate group on mPEG- NCO with hydroxy groups on chitosan chains because amino groups on chitosan chains were protected by complexion formation with copper ions. The effect of reaction condition on the grafting extents was discussed. Swelling properties of mPEG-g-CS were researched. The graft copolymer mPEG-g-CS was characterized by the infrared spectra. The experimental result showed that the copper ions were very effective to protect amino groups from condensation reaction. The swelling degree in water increases with adding of grafting ratio. The maximum swelling degree was up to above 132% when the grafting ratio was about 270%. The graft copolymer can be soluble partially in pure water.
文摘To solve the so called “white rust” and ’water bridge" problems of the aluminum fins for heat exchanger of automobile air conditioner, aimed at nationalizing the art of hydrophilic coating technology, the choice of coating forming and curing materials was investigated. By measuring the water contact angle, SEM surface scanning and ingredients analysis of the coating, optimal parameters and composition are acquired. The coating forming mechanisms of the composition was also expatiated. The coating obtained has good hydrophilic and other properties.
基金Supported by the National Natural Science Foundation of China(No.30901644)the Fundamental Research Funds for the Central Universities of China
文摘·AIM: To compare posterior capsule opacification(PCO)degree and visual functions after phacoemulsification in eyes implanted with 360-degree square edge hydrophilic acrylic intraocular lens(IOL)(570C C-flex, Rayner) and sharp edge hydrophobic acrylic IOL(Sensar AR40 e,AMO) in diabetic patients.· METHODS: Sixty diabetic patients underwent uneventful phacoemulsification and randomly implanted one of the two IOLs. The PCO value was measured by retroillumination photographs and Evaluation of Posterior Capsule Opacification(EPCO) 2000 image-analysis software at 1, 6, 12, and 24 mo after surgery. Visual acuity, and contrast sensitivity in photopic and mesopic conditions were also examined at each follow up time point. The incidence of eye that required Nd:YAG laser posterior capsulotomy were also compared.·RESULTS: There was not any statistically significant difference in PCO scores between Rayner C-flex 570 C group and Sensar AR40 e group at each follow up time point. Visual acuity, Nd:YAG capsulotomy incidence and contrast sensitivity also had no significant difference during the 24 mo follow-up.·CONCLUSION: For diabetic patients, Rayner 570 C Cflex and Sensar AR40 e IOLs are same effective for prevent PCO. The 360-degree square edge design maybe is a good alternative technique to improve PCO prevention.
基金Project supported by the National Natural Science Foundation of China(Grant No.11175157)the Zhejiang Provincial Key Innovation Team,China(Grant No.2012R10038)the 521 Talent Project of Zhejiang Sci-Tech University,China
文摘Three different low-temperature plasma-based methods were used to improve the surface hydrophilicity of polyethy- lene (PE) films, and all the modification processes were carried out by employing an atmospheric pressure plasma jet (APPJ) system. (a) PE films were directly modified by APPJ using a gas mixture of He and 02. (b) Acrylic acid (AA) was introduced into the system and a polymer acrylic acid (PAA) coating was deposited onto the PE films. (c) AA was grafted onto the PE surface activated by plasma pre-treatment. It was found that the hydrophilicity of the PE films was significantly improved for all the three methods. However, the samples modified by Process (a) showed hydrophobicity recovery after a storage time of 20 days while no significant change was found in samples modified by Process (b) and Process (c). The Fourier transform infrared spectroscopy (FTIR) results indicated that the most intensive C=O peak was detected on the PE surface modified by Process (c). According to the X-ray photoelectron spectroscopy (XPS) analysis, the ratios of oxygen-containing polar groups for samples modified by Process (b) and Process (c) were higher than that modified by Process (a).
基金Supported by the National Key R&D Plan(2016YFC0205700)the National Natural Science Foundation of China(91534108,21506093,21706114)+2 种基金the Natural Science Foundation of Jiangsu Province(BK20150947,BK20160979)the National High Technology Research and Development Program of China(2012AA03A606)the Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Hydrophilic ceramic membranes would be potential candidates for membrane gas absorption if they could be applied to appropriate separation processes.This study highlights a novel concept for the practical implementation of SO_2 absorption in hydrophilic ceramic membrane that exhibits outstanding thermal and mechanical stabilities.With this aim,we investigated experimentally the performance of SO_2 absorption into aqueous sodium hydroxide (NaOH) solution in a hydrophilic alumina (Al_2O_3) membrane contactor in terms of SO_2 removal efficiency and SO_2 mass transfer flux,and compared the performance with that in a hydrophobic one.A series of experiments were performed at various conditions over a NaOH concentration range of 0–1.0 mol·L^(-1),a liquid flow rate range of 30–180 ml·min^(-1),a gas flow rate range of 120–1000 ml·min^(-1),an inlet SO_2 concentration range of 400–2000μl·L^(-1),and a temperature range of 10–35°C.It was found that the hydrophilic membrane was more competitive when using a NaOH concentration higher than 0.2 mol·L^(-1).Furthermore,it can be inferred that the hydrophilicα-Al_2O_3 membrane exhibited exceptional long-term stability under 480 h continuous operation.
基金Supported by the National Natural Science Foundation of China(Nos.20502017, 20872102)
文摘A new Fenton-like system in a medium of hydrophilic triethylammonium type of ionic liquid(IL) was used for the hydroxylation of benzene to phenol. The triethylammonium acetate([Et3NH][CH3COO]) IL exhibited retardation performance for the decomposition of H2O2 and protection performance for the further oxidation of phenol, thus the yield and selectivity to phenol were promoted greatly. The acidity of the system was proved to be an important factor for the selectivity to phenol. The utilization of H2O2 and the selectivity to phenol, as well as the Turnover number(TON) of the catalyst were effectively enhanced by a benzene-[Et3NH][CH3COO] bi-phase system. The catalyst with [Et3NH][CH3COO] IL was recycled with stable catalytic performance.
文摘A novel technology of preparation of felt-metal supported modified polyvinyl alcohol(PVA) ultrafiltration(UF) membrane was invented, which could avoid the blockage of the holes of support layer and the leakage of the casting solution through the holes of support layer. Felt-metal supported ferric sulfate modified PVA composite UF membranes were prepared by the innovative technology. The results show that the composite membranes are used to treat 1 000 mg/L oil/water emulsion at trans-membrane pressure from 0.25 to 0.45 MPa, the permeate flux is from 36 to 52 L/(m2·h), and the retention of chemical oxygen demand(COD) is over 92%. The composite membrane resistance increases with the increase of trans-naembrane pressure.
文摘The processing of an energy carrier such as microalgae oil into valuable fuels and chemicals is quite promising.Aqueous-phase processing is suitable for this purpose because the separation of intrinsic water from the algae cell is difficult.In this study,we synthesized ruthenium(Ru)nanoparticles supported on highly hydrophilic mesoporous carbon to catalyze the quantitative hydrodeoxygenation(HDO)of microalgae oil to alkanes in a one-pot process at a low temperature(140℃)in the aqueous phase.The mesoporous carbon was obtained by single-step calcination of starch and zinc chloride in nitrogen.The as-obtained carbon showed high surface areas and pore volumes,allowing high dispersion of Ru nanoparticles.The surface of the carbon material was rich in hydroxyl groups,as evidenced by X-ray photoelectron spectroscopy(XPS),infrared(IR)spectroscopy,and thermogravimetric analysis(TGA)measurements.As a result,the carbon material contacted preferably with the water phase versus the organic phase,improving the accessibility of substrates.On the other hand,the contact angle test results speculated the superior hydrophilic nature of mesoporous Ru/C(ZnCl2,starch)than commercial Ru/C.Both kinetics modeling and in situ IR monitoring in water revealed the superior performance of the hydrophilic mesoporous and hydrophilic Ru/C compared to a commercial Ru/C for the tandem hydrogenation of stearic acid and decarbonylation of stearyl alcohol.The herein designed hydrothermal carbon material was highly active,environmentally benign,sustainable,and recyclable material,and could be potentially used for other hydrogenation reactions in the aqueous phase.
文摘Novel double hydrophilic block copolymers with amine pendant chains were synthesized by polymerization of 4-vinyl benzylamine hydrochloric salt using 4,4′-azo-bis[4-cyanopentanoate poly(ethylene glycol) ester] as macroazoinitiator. The structures of the copolymers were characterized by ^1H NMR, FTIR spectra and acid-base titration, GPC-MALS techniques.
基金Funded by Key Scientific and Technological Items of the Ministry of Education (No.99087) .
文摘TiO2-SiO2 thin films have been prepared on slide glass substrates by sol-gel method, and the effect of SiO2 additive on photo-generated hydrophilicity of TiO2 thin film was investigated by measuring the contact angle of water, the microstructure, the transmittance, the photocatalytic activity and the specific surface area . The results showed that 10mol% of SiO2 additive was the most effective for decreasing contact angle of water. The SiO2 additive of less than 30mol% has a suppressive effect on the crystal growth of anatase in calcinations, resulting in a large surface area. Consequently, the super-hydrophilicity was improved.