[Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by ga...[Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by gas chromatography-mass spectrometry(GC-MS)in selective ion scanning mode(SIM).[Results]The organophosphorus pesticide standard solutions showed good linearity in the mass concentration range of 0.1-10.0μg/ml with correlation coefficients(r)not lower than 0.999,and the detection limits(S=3 N)ranged from 0.01 to 0.05 mg/kg.The average recovery values were in the range of 80.2%-99.7%,with relative standard deviations(RSDs,n=3)in the range of 1.8%-6.3%,at the addition levels of 0.5,1.0 and 2.0 mg/kg.[Conclusions]The method is simple,sensitive and accurate,and can be used for the determination of organophosphorus pesticide residues in mutton.展开更多
Borneol, as a traditional natural permeation enhancer, has been widely used to promote the transdermal absorption of active ingredients. In this review, the mechanism of borneol in promoting permeation by destroying t...Borneol, as a traditional natural permeation enhancer, has been widely used to promote the transdermal absorption of active ingredients. In this review, the mechanism of borneol in promoting permeation by destroying the highly ordered lipid structure of the lipid layer and by destroying the hydrogen-bond network was described. The application of borneol in promoting the transdermal absorption of the active ingredients of traditional Chinese medicine and chemical drugs was introduced. The application of borneol as a natural ingredient added to functional cosmetics was summarized, and its effects on skin-spot treatment, acne skin care, eczema skin care, skin repair and anti-oxidation were introduced. Finally, the possible problems in the application of borneol in cosmetics were put forward, and the application prospect of borneol in the development of cosmetics was given.展开更多
Background:More and more consumers are paying attention to skin rejuvenation.However,there is a lack of a non-invasive and efficient solution.Objective:To evaluate the efficacy of a trinity permeation synergism(TPS),w...Background:More and more consumers are paying attention to skin rejuvenation.However,there is a lack of a non-invasive and efficient solution.Objective:To evaluate the efficacy of a trinity permeation synergism(TPS),which consists of a firming essence,an atomizer and a photoelectric penetrator,for facial anti-aging efficacy.Material and methods:In this work,in vitro cell experiments and human efficacy study were used to evaluate the firming and anti-wrinkle effects.Cell experiments were used to verify the effect of the firming essence on the cell proliferation,migration,and anti-inflammation in keratinocytes(HaCaT),and on the gene expression levels of type I and type III collagen(Col-1 and Col-3)and type I matrix metalloproteinase(MMP-1)in human skin fibroblasts(HSF).After in vitro test,60 women aged 35–60 years were enrolled in the randomized test,of which 30 subjects were randomly selected to be the experimental group and treated with the TPS system,while the left 30 subjects were treated with the firming essence only considered as control.After 28 days,skin elasticity,skin redness value,and skin wrinkles were measured to evaluate the efficacy of the TPS system.Results:Cell experiments showed that the firming essence can significantly improve the proliferation and the migration of HaCaT cells.It also promoted the expression level of Col-1 and Col-3 gene,and inhibited the expression level of MMP-1 gene in HSF cells.After confirming the efficacy of firming essence,the efficacy benefit of the TPS was further studied.The 28-day tests show that combined use firming essence with atomizer and penetrator can significantly increase skin elasticity,reduce skin hemoglobin value and skin wrinkles on Day 28.Moreover,all the mentioned improvements are significantly better than that in the control group.Conclusion:Through efficient delivery in the whole process,TPS boosts the efficacy of active components in the firming essence.TPS offers an efficient,non-invasive,and convenient way for enhanced facial rejuvenation efficacy.展开更多
Gas-driven permeation(GDP)and plasma-driven permeation(PDP)of hydrogen gas through Ga In Sn/Fe are systematically investigated in this work.The permeation parameters of hydrogen through Ga In Sn/Fe,including diffusivi...Gas-driven permeation(GDP)and plasma-driven permeation(PDP)of hydrogen gas through Ga In Sn/Fe are systematically investigated in this work.The permeation parameters of hydrogen through Ga In Sn/Fe,including diffusivity,Sieverts'constant,permeability,and surface recombination coefficient are obtained.The permeation flux of hydrogen through Ga In Sn/Fe shows great dependence on external conditions such as temperature,hydrogen pressure,and thickness of liquid Ga In Sn.Furthermore,the hydrogen permeation behavior through Ga In Sn/Fe is well consistent with the multilayer permeation theory.In PDP and GDP experiments,hydrogen through Ga In Sn/Fe satisfies the diffusion-limited regime.In addition,the permeation flux of PDP is greater than that of GDP.The increase of hydrogen plasma density hardly causes the hydrogen PDP flux to change within the test scope of this work,which is due to the dissolution saturation.These findings provide guidance for a comprehensive and systematic understanding of hydrogen isotope recycling,permeation,and retention in plasma-facing components under actual conditions.展开更多
Fe–S compounds with hexagonal crystal structure are potential hydrogen permeation barrier during H2S corrosion. Hexagonal system Fe–S films were prepared on carbon steel through corrosion and CVD deposition, and the...Fe–S compounds with hexagonal crystal structure are potential hydrogen permeation barrier during H2S corrosion. Hexagonal system Fe–S films were prepared on carbon steel through corrosion and CVD deposition, and the barrier effect of different Fe–S films on hydrogen permeation was tested using electrochemical hydrogen permeation method. After that, the electrical properties of Fe–S compound during phase transformation were measured using thermoelectric measurement system. Results show that the mackinawite has no obvious barrier effect on hydrogen penetration, as a p-type semiconductor, and pyrrhotite (including troilite) has obvious barrier effect on hydrogen penetration,as an n-type semiconductor. Hydrogen permeation tests showed peak permeation performance when the surface was deposited with a continuous film of pyrrhotite (Fe_(1–x)S) and troilite. The FeS compounds suppressed hydrogen permeation by the promotion of the hydrogen evolution reaction, semiconducting inversion from p-to n-type, and the migration of ions at the interface.展开更多
Borneol,as a traditional natural permeation enhancer,has been widely used to promote the transdermal absorption of active ingredients.The mechanism of borneol in promoting permeation by destroying the highly ordered l...Borneol,as a traditional natural permeation enhancer,has been widely used to promote the transdermal absorption of active ingredients.The mechanism of borneol in promoting permeation by destroying the highly ordered lipid structure of the lipid layer and by destroying the hydrogen-bond network was described.The application of borneol in promoting the transdermal absorption of the active ingredients of traditional Chinese medicine and chemical drugs was introduced.The application of borneol as a natural ingredient added to functional cosmetics was summarized,and its effects on skin-spot treatment,acne skin care,eczema skin care,skin repair and anti-oxidation were introduced.Finally,the possible problems in the application of borneol in cosmetics were put forward,and the application prospect of borneol in the development of cosmetics was given。展开更多
The effect of pH on the permeation of Lidocaine hydrochloride (LH) across excised rat skin was studied, the steady state flux (JSS) at different pH being determined using improved Valia-Chien diffusion cells. JSS incr...The effect of pH on the permeation of Lidocaine hydrochloride (LH) across excised rat skin was studied, the steady state flux (JSS) at different pH being determined using improved Valia-Chien diffusion cells. JSS increased substantially when pH was close to the pKa of LH. The profile of JSS versus pH showed an 慡?shaped curve. JSS of Lidocaine free base (LFB) was fourteen times that of LH. The pH of vehicle influences the permeation of LH significantly and should be considered as an important factor when a formulation is developed.展开更多
The phase composition, microstructure, thermal expansion coefficients, oxygen permeation properties and chemical stability of SrCo0.8Fe0.2O3-δ （SCFM） were investigated and compared with those of SrCo0.8Fe0.2O3-δ（...The phase composition, microstructure, thermal expansion coefficients, oxygen permeation properties and chemical stability of SrCo0.8Fe0.2O3-δ （SCFM） were investigated and compared with those of SrCo0.8Fe0.2O3-δ（SCF）. Single phase SCFM was successfully prepared by a combined EDTA-citric method. SCFM shows a lower thermal expansion coefficient （24× 10^-6-29× 10^-6/K） than SCF between 500 and 1050 ℃, indicating a more stable structure. SCFM shows a high oxygen permeation flux, although the oxygen flux of SCFM decreases slightly because of Mo dopant. Furthermore, it was demonstrated that the doping of Mo in SCF can prevent the order-disorder transition and improves the chemical stability to CO2.展开更多
A hydrogen permeation barrier was manufactured by the in situ reaction of zirconium hydride with oxygen. A reduction in the hydrogen permeation of the oxide films was detected by measuring the mass difference of the z...A hydrogen permeation barrier was manufactured by the in situ reaction of zirconium hydride with oxygen. A reduction in the hydrogen permeation of the oxide films was detected by measuring the mass difference of the zirconium hydride samples after the dehydrogenation experiment. The reaction of zirconium hydride with oxygen occurs only under the condition that the temperature is higher than 673 K in the oxygen partial pressure of 0.1 MPa. The oxide film is composed of two layers, a permeable oxide layer and a dense oxide layer, and the main phase of the oxide film is ZrO2 with baddeleyite structure. The XPS analysis shows that O-H bonds exist in the oxide film, which are helpful for resisting hydrogen diffusion through the oxide film.展开更多
The hydrogen permeation behavior and stress corrosion cracking （SCC） susceptibility of precharged 7075-T6 A1 alloy were inves- tigated in this paper. Devanthan-Stachurski （D-S） cell tests were used to measure the ...The hydrogen permeation behavior and stress corrosion cracking （SCC） susceptibility of precharged 7075-T6 A1 alloy were inves- tigated in this paper. Devanthan-Stachurski （D-S） cell tests were used to measure the apparent hydrogen diffusivity and hydrogen permeation current density of specimens immersed in 3.5wt% NaCl solution. Electrochemical experiment results show that the SCC susceptibility is low during anodic polarization. Both corrosion pits and hydrogen-induced cracking are evident in scanning electron microscope images after the specimens have been charging for 24 h.展开更多
Atomic layer deposition （ALD） technique is used in the preparation of organic/inorganic layers, which requires uniform surfaces with their thickness down to several nanometers. For film with such thickness, the grow...Atomic layer deposition （ALD） technique is used in the preparation of organic/inorganic layers, which requires uniform surfaces with their thickness down to several nanometers. For film with such thickness, the growth mode defined as the arrangement of clusters on the surface during the growth is of significance. In this work, Al2O3 thin film was deposited on various interfacial species of pre-treated polyethylene terephthalate （PET, 12 μm） by plasma assisted atomic layer deposition （PA-ALD）, where trimethyl aluminium was used as the Al precursor and O2 as the oxygen source. The interracial species, -NH3, -OH, and -COOH as well as SiCHO （derived from monomer of HMDSO plasma）, were grafted previously by plasma and chemical treatments. The growth mode of PA-ALD Al2O3 was then investigated in detail by combining results from in-situ diagnosis of spectroscopic ellipsometry （SE） and ex-situ characterization of as-deposited layers from the morphologies scanned by atomic force microscopy （AFM）. In addition, the oxygen transmission rates （OTR） of the original and treated plastic films were measured. The possible reasons for the dependence of the OTR values on the surface species were explored.展开更多
A cationic gene delivery vector, guanidinylated disulfide-containing poly(amido amine)(CARCBA), was synthesized by Michael addition reaction between N,N′-cystaminebisacrylamide(CBA) and guanidine hydrochloride(CAR). ...A cationic gene delivery vector, guanidinylated disulfide-containing poly(amido amine)(CARCBA), was synthesized by Michael addition reaction between N,N′-cystaminebisacrylamide(CBA) and guanidine hydrochloride(CAR). Gel permeation chromatography(GPC) was used to evaluate the molecular weight of synthesized CAR-CBA. Polyethyleneimine(PEI) with molecular weight of 25 kDa was adopted as a reference, and polyethylene glycols(PEG) with different molecular weights were used to establish a standard curve for determining the molecular weight of CAR-CBA. The effects of two critical factors, namely columns and eluents,on the molecular weight measurement of CAR-CBA were investigated to optimize the GPC quantitative method. The results showed that Ultrahydrogel columns(120, 250) and HAc–NaAc(0.5 M, pH 4.5) buffer solution were the optimal column and GPC eluent, respectively.The molecular weight of the synthesized CAR-CBA was analyzed by the optimized GPC method and determined to be 24.66 kDa.展开更多
In order to improve the surface hardness and wear resistance of Ti and Ti alloy components, an oxygen permeation treatment (OPT) was developed. The oxygen permeation behaviors of three Ti alloys, TA2, TB5 and TC11, tr...In order to improve the surface hardness and wear resistance of Ti and Ti alloy components, an oxygen permeation treatment (OPT) was developed. The oxygen permeation behaviors of three Ti alloys, TA2, TB5 and TC11, treated in air with O-P medium at high temperature have been studied. The results show that the 0-P treatment can significantly improve the surface hardness of Ti alloys. The oxidation mass-gain of β-Ti alloy (TB5) is much higher than α-Ti alloy (TA2) under the same condition, while α+β Ti alloy (TC11) is the lowest. All the Ti alloys treated at this condition produce two surface layers: the outer layer consists mainly of TiO2, as well as trace of other oxides, and the inner layer consists of a Ti-O interstitial solid solution formed by the diffusion of oxygen in α crystal lattice. Thick scales of β Ti alloy (TB5) are easily formed depending mainly on the poor solid solution content of oxygen, while deep solution layer can be formed since partial β phase has been transformed into α phase. The scales of α-β Ti alloy (TC11) are very thin and compact. Aluminum-rich zone, as well as deficient zone, is found in oxide layers. A crystallographic characterization of oxygen solution layer has been performed and evaluated by crystallographic lattice constant.展开更多
A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 s...A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 steroid hormones were extracted from the tissues with diethyl ether.Differing from other common purification methods,the extract solutions were cleaned by gel permeation chromatography(GPC) using ethyl acetate-cyclohexane solution(1:1,v/v) as the mobile phase.The separation of target compounds was carried out by a BEH C18 column and a gradient elution consisting of acetonitrile and 0.2% aqueous formic acid(v/v).The compounds were detected under the multiple reaction monitoring(MRM) mode and quantified with external standard method.This method was validated with respect to linearity,specificity,accuracy and precision.A linearity with correlation coefficient larger than 0.995 was achieved in the range of 0.5 to 50 ng m L^(-1).The average recoveries at the spiked levels of 1.0,5.0,and 10.0 μg kg^(–1) varied between 81.7% and 90.8%,with the relative standard deviations(n=5) ranged from 3.50% to 10.0%.The limit of quantification(LOQ) for 8 steroid hormones ranged from 0.2 to 1.5 μg kg^(-1).It was concluded that this method can be successfully applied for the determination of 8 steroid hormones in complicated matrices including high-fat fish tissues.展开更多
The effect of pulse frequency and current density on the effectiveness ofbiphasic pulse electrocleaning is discussed. Moderate frequency (5Hz) is found to be more effectivethan lower or higher frequency on steel surfa...The effect of pulse frequency and current density on the effectiveness ofbiphasic pulse electrocleaning is discussed. Moderate frequency (5Hz) is found to be more effectivethan lower or higher frequency on steel surface cleanliness. A novel interpretation of cyclicvoltammagrams is used to estimate the surface cleanliness. This correlates very well with XPSdetermination of surface carbon levels. This result is discussed in terms of mechanisms ofelectrocleaning. Moderate frequency (5-10Hz) is more effective than lower frequency for inhibitinghydrogen permeation. This method can prevent hydrogen brittleness on the electrocleaninghigh-strength steel.展开更多
New polyoxometalate α-K 12H 3[Y(BW 11O 39) 2]·25H 2O was synthesized and treated by high temperature gaseous rare earth permeation to prepare tungsten bronze K 0.475WO 3. XRD, TG-DTA, XPS, ...New polyoxometalate α-K 12H 3[Y(BW 11O 39) 2]·25H 2O was synthesized and treated by high temperature gaseous rare earth permeation to prepare tungsten bronze K 0.475WO 3. XRD, TG-DTA, XPS, 183W-NMR,CV and AC impedance spectra were used to characterize the resulting material. The results of XPS indicate that La has permeated and diffused into the body of the sample and exists in the forms of binding with other components. The crystal structure parameters of K 0.475WO 3 were obtained by the analysis of XRD, which shows tetragonal crystal system with lattice parameters: a=12 28 nm, c=3.833 nm, V=578.48 nm -3. The conductivities calculated from the results of AC impedance spectra of the material increase with the increasing of temperature, which shows a semiconductor character.展开更多
Transdermal drug delivery has been accepted as a potential non-invasive route of drug administration,with advantages of prolonged therapeutic action,decreased side effect,easy use and better patient compliance.However...Transdermal drug delivery has been accepted as a potential non-invasive route of drug administration,with advantages of prolonged therapeutic action,decreased side effect,easy use and better patient compliance.However,development of transdermal products is primarily hindered by the low permeability of the skin.To overcome this barrier effect,numerous new chemicals have been synthesized as potential permeation enhancers for transdermal drug delivery.In this review,we presented an overview of the investigations in this field,and further implications on selection or design of suitable permeation enhancers for transdermal drug delivery were also discussed.展开更多
Ba0.9R0.1Co0.TFe0.225Ta0.07503-δ （BRCFT, R = Ca, La or Sr） membranes were synthesized by a solid-state reaction. Metal cation Ca2＋, La3＋ or Sr2＋ doping on A-site partially substituted Ba2＋ in BaCoo.TFe0.225Ta0....Ba0.9R0.1Co0.TFe0.225Ta0.07503-δ （BRCFT, R = Ca, La or Sr） membranes were synthesized by a solid-state reaction. Metal cation Ca2＋, La3＋ or Sr2＋ doping on A-site partially substituted Ba2＋ in BaCoo.TFe0.225Ta0.07503-δ oxides, and its subsequent effects on phase structure stability, oxygen permeability and oxygen desorption were systematically investigated by XRD, TG-DSC, Hz-TPR, O2-TPD techniques and oxygen permeation experiments. The partial substitution with Ca2＋, La3＋ or Sr2＋, whose ionic radii are smaller than that of Ba2＋, succeeded in stabilizing the cubic perovskite structure without formation of impurity phases, as revealed by XRD analysis. Oxygen-involving experi- ments showed that BRCFT with A-site fully occupied by Ba2＋ exhibited good oxygen permeation flux under He flow, reaching about 2.3 mL.min-l .cm-2 at 900 with I mm thickness. Of all the membranes, BLCFT membrane showed better chemical stability in CO2, owing to the reduction in alkalinity of the mixed conductor oxide by La doping. In addition, we also found the stability of the perovskite structure under reducing atmospheres was strengthened by increasing the size of A-site cation （Ba2＋〉La3＋〉SrZ＋〉Ca2＋）.展开更多
Zr-substituted,Tm-doped SrCeO3（SrCe0.95-xZrxTm0.05O3-δ,0≤x≤0.40）were synthesized via citrate complexing method,and the membranes of SrCe0.95-xZrxTm0.05O3-δwere prepared by pressing followed by sintering. X-ray d...Zr-substituted,Tm-doped SrCeO3（SrCe0.95-xZrxTm0.05O3-δ,0≤x≤0.40）were synthesized via citrate complexing method,and the membranes of SrCe0.95-xZrxTm0.05O3-δwere prepared by pressing followed by sintering. X-ray diffraction（XRD）was used to characterize the phase structure of sintered membrane.The microstructure of the sintered membranes was studied by scanning electron microscopy（SEM）.Protonic and electronic conductivities were measured under different circumstance.Hydrogen permeation through the SrCe0.75Zr0.20Tm0.05O3-δmembranes was carried out using gas permeation setup.Hydrogen permeation fluxes（ 2H J）of the SrCe0.75Zr0.20Tm0.05O3-δ membrane reach up to 0.042 ml·min^ -1 ·cm^-2 at H 2 partial pressure of 0.4×10 ^5 Pa at 900°C.The hydrogen permea- tion fluxes（ 2H J）obtained in this paper are slightly lower than that of SrCe0.95Tm0.05O3-δon the same orders,and Zr doping can increase chemical stability of the SrCe0.75Zr0.20Tm0.05O3-δmembranes.展开更多
The electrical conduction properties of dense BaCe0.9Mn0.1O3-d (BCM10) membrane were investigated in the temperature range of 600-900oC. High ionic and electronic conductivities at elevated temperatures make BCM10 a ...The electrical conduction properties of dense BaCe0.9Mn0.1O3-d (BCM10) membrane were investigated in the temperature range of 600-900oC. High ionic and electronic conductivities at elevated temperatures make BCM10 a potential ceramic material for hydrogen separation. Hydrogen permeation through BCM10 membranes was studied using a high- temperature permeation cell. Little hydrogen could be detected at the sweep side. However, appreciable hydrogen can permeate through BCM10 membrane coated with porous platinum black, which shows that the process of hydrogen permeation through BCM10 membranes was controlled by the catalytic decomposition and recomposition of hydrogen on the surfaces of BCM10 membranes.展开更多
基金Supported by The Fourth Batch of High-end Talent Project in Hebei Province.
文摘[Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by gas chromatography-mass spectrometry(GC-MS)in selective ion scanning mode(SIM).[Results]The organophosphorus pesticide standard solutions showed good linearity in the mass concentration range of 0.1-10.0μg/ml with correlation coefficients(r)not lower than 0.999,and the detection limits(S=3 N)ranged from 0.01 to 0.05 mg/kg.The average recovery values were in the range of 80.2%-99.7%,with relative standard deviations(RSDs,n=3)in the range of 1.8%-6.3%,at the addition levels of 0.5,1.0 and 2.0 mg/kg.[Conclusions]The method is simple,sensitive and accurate,and can be used for the determination of organophosphorus pesticide residues in mutton.
文摘Borneol, as a traditional natural permeation enhancer, has been widely used to promote the transdermal absorption of active ingredients. In this review, the mechanism of borneol in promoting permeation by destroying the highly ordered lipid structure of the lipid layer and by destroying the hydrogen-bond network was described. The application of borneol in promoting the transdermal absorption of the active ingredients of traditional Chinese medicine and chemical drugs was introduced. The application of borneol as a natural ingredient added to functional cosmetics was summarized, and its effects on skin-spot treatment, acne skin care, eczema skin care, skin repair and anti-oxidation were introduced. Finally, the possible problems in the application of borneol in cosmetics were put forward, and the application prospect of borneol in the development of cosmetics was given.
文摘Background:More and more consumers are paying attention to skin rejuvenation.However,there is a lack of a non-invasive and efficient solution.Objective:To evaluate the efficacy of a trinity permeation synergism(TPS),which consists of a firming essence,an atomizer and a photoelectric penetrator,for facial anti-aging efficacy.Material and methods:In this work,in vitro cell experiments and human efficacy study were used to evaluate the firming and anti-wrinkle effects.Cell experiments were used to verify the effect of the firming essence on the cell proliferation,migration,and anti-inflammation in keratinocytes(HaCaT),and on the gene expression levels of type I and type III collagen(Col-1 and Col-3)and type I matrix metalloproteinase(MMP-1)in human skin fibroblasts(HSF).After in vitro test,60 women aged 35–60 years were enrolled in the randomized test,of which 30 subjects were randomly selected to be the experimental group and treated with the TPS system,while the left 30 subjects were treated with the firming essence only considered as control.After 28 days,skin elasticity,skin redness value,and skin wrinkles were measured to evaluate the efficacy of the TPS system.Results:Cell experiments showed that the firming essence can significantly improve the proliferation and the migration of HaCaT cells.It also promoted the expression level of Col-1 and Col-3 gene,and inhibited the expression level of MMP-1 gene in HSF cells.After confirming the efficacy of firming essence,the efficacy benefit of the TPS was further studied.The 28-day tests show that combined use firming essence with atomizer and penetrator can significantly increase skin elasticity,reduce skin hemoglobin value and skin wrinkles on Day 28.Moreover,all the mentioned improvements are significantly better than that in the control group.Conclusion:Through efficient delivery in the whole process,TPS boosts the efficacy of active components in the firming essence.TPS offers an efficient,non-invasive,and convenient way for enhanced facial rejuvenation efficacy.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11905151 and 11875198)the National Key Research and Development Program of China(Grant No.2022YFE03130000)。
文摘Gas-driven permeation(GDP)and plasma-driven permeation(PDP)of hydrogen gas through Ga In Sn/Fe are systematically investigated in this work.The permeation parameters of hydrogen through Ga In Sn/Fe,including diffusivity,Sieverts'constant,permeability,and surface recombination coefficient are obtained.The permeation flux of hydrogen through Ga In Sn/Fe shows great dependence on external conditions such as temperature,hydrogen pressure,and thickness of liquid Ga In Sn.Furthermore,the hydrogen permeation behavior through Ga In Sn/Fe is well consistent with the multilayer permeation theory.In PDP and GDP experiments,hydrogen through Ga In Sn/Fe satisfies the diffusion-limited regime.In addition,the permeation flux of PDP is greater than that of GDP.The increase of hydrogen plasma density hardly causes the hydrogen PDP flux to change within the test scope of this work,which is due to the dissolution saturation.These findings provide guidance for a comprehensive and systematic understanding of hydrogen isotope recycling,permeation,and retention in plasma-facing components under actual conditions.
基金financailly supported by the National Natural Science Foundation of China (Nos.52275198 and 51805292)the Beijing Natural Science Foundation,China(No.2202020)the Tribology Science Fund of State Key Laboratory of Tribology,China (No.SKLT2022B11)。
文摘Fe–S compounds with hexagonal crystal structure are potential hydrogen permeation barrier during H2S corrosion. Hexagonal system Fe–S films were prepared on carbon steel through corrosion and CVD deposition, and the barrier effect of different Fe–S films on hydrogen permeation was tested using electrochemical hydrogen permeation method. After that, the electrical properties of Fe–S compound during phase transformation were measured using thermoelectric measurement system. Results show that the mackinawite has no obvious barrier effect on hydrogen penetration, as a p-type semiconductor, and pyrrhotite (including troilite) has obvious barrier effect on hydrogen penetration,as an n-type semiconductor. Hydrogen permeation tests showed peak permeation performance when the surface was deposited with a continuous film of pyrrhotite (Fe_(1–x)S) and troilite. The FeS compounds suppressed hydrogen permeation by the promotion of the hydrogen evolution reaction, semiconducting inversion from p-to n-type, and the migration of ions at the interface.
文摘Borneol,as a traditional natural permeation enhancer,has been widely used to promote the transdermal absorption of active ingredients.The mechanism of borneol in promoting permeation by destroying the highly ordered lipid structure of the lipid layer and by destroying the hydrogen-bond network was described.The application of borneol in promoting the transdermal absorption of the active ingredients of traditional Chinese medicine and chemical drugs was introduced.The application of borneol as a natural ingredient added to functional cosmetics was summarized,and its effects on skin-spot treatment,acne skin care,eczema skin care,skin repair and anti-oxidation were introduced.Finally,the possible problems in the application of borneol in cosmetics were put forward,and the application prospect of borneol in the development of cosmetics was given。
文摘The effect of pH on the permeation of Lidocaine hydrochloride (LH) across excised rat skin was studied, the steady state flux (JSS) at different pH being determined using improved Valia-Chien diffusion cells. JSS increased substantially when pH was close to the pKa of LH. The profile of JSS versus pH showed an 慡?shaped curve. JSS of Lidocaine free base (LFB) was fourteen times that of LH. The pH of vehicle influences the permeation of LH significantly and should be considered as an important factor when a formulation is developed.
文摘The phase composition, microstructure, thermal expansion coefficients, oxygen permeation properties and chemical stability of SrCo0.8Fe0.2O3-δ （SCFM） were investigated and compared with those of SrCo0.8Fe0.2O3-δ（SCF）. Single phase SCFM was successfully prepared by a combined EDTA-citric method. SCFM shows a lower thermal expansion coefficient （24× 10^-6-29× 10^-6/K） than SCF between 500 and 1050 ℃, indicating a more stable structure. SCFM shows a high oxygen permeation flux, although the oxygen flux of SCFM decreases slightly because of Mo dopant. Furthermore, it was demonstrated that the doping of Mo in SCF can prevent the order-disorder transition and improves the chemical stability to CO2.
基金the National Natural Science Foundation of China (No. 50674015)
文摘A hydrogen permeation barrier was manufactured by the in situ reaction of zirconium hydride with oxygen. A reduction in the hydrogen permeation of the oxide films was detected by measuring the mass difference of the zirconium hydride samples after the dehydrogenation experiment. The reaction of zirconium hydride with oxygen occurs only under the condition that the temperature is higher than 673 K in the oxygen partial pressure of 0.1 MPa. The oxide film is composed of two layers, a permeable oxide layer and a dense oxide layer, and the main phase of the oxide film is ZrO2 with baddeleyite structure. The XPS analysis shows that O-H bonds exist in the oxide film, which are helpful for resisting hydrogen diffusion through the oxide film.
基金financially supported by the Natural Science Foundation of Jiangsu Province, China (No. BK20141292)the Foundation of Key Laboratory of Marine Environmental Corrosion and Bio-fouling, Institute of Oceanology, Chinese Academy of Sciences (No. MCKF201412)
文摘The hydrogen permeation behavior and stress corrosion cracking （SCC） susceptibility of precharged 7075-T6 A1 alloy were inves- tigated in this paper. Devanthan-Stachurski （D-S） cell tests were used to measure the apparent hydrogen diffusivity and hydrogen permeation current density of specimens immersed in 3.5wt% NaCl solution. Electrochemical experiment results show that the SCC susceptibility is low during anodic polarization. Both corrosion pits and hydrogen-induced cracking are evident in scanning electron microscope images after the specimens have been charging for 24 h.
基金supported by National Natural Science Foundation of China (No.11175024)Beijing Natural Science Foundation (No.1112012),2011BAD24B01+1 种基金Scientific Research Common Program of Beijing Municipal Commission of Education(KM201110015008,KM201010015005)Funding Project for Academic Human Resources Development in Institutions of Higher Learning Under theJurisdiction of Beijing Municipality (PHR20110516)
文摘Atomic layer deposition （ALD） technique is used in the preparation of organic/inorganic layers, which requires uniform surfaces with their thickness down to several nanometers. For film with such thickness, the growth mode defined as the arrangement of clusters on the surface during the growth is of significance. In this work, Al2O3 thin film was deposited on various interfacial species of pre-treated polyethylene terephthalate （PET, 12 μm） by plasma assisted atomic layer deposition （PA-ALD）, where trimethyl aluminium was used as the Al precursor and O2 as the oxygen source. The interracial species, -NH3, -OH, and -COOH as well as SiCHO （derived from monomer of HMDSO plasma）, were grafted previously by plasma and chemical treatments. The growth mode of PA-ALD Al2O3 was then investigated in detail by combining results from in-situ diagnosis of spectroscopic ellipsometry （SE） and ex-situ characterization of as-deposited layers from the morphologies scanned by atomic force microscopy （AFM）. In addition, the oxygen transmission rates （OTR） of the original and treated plastic films were measured. The possible reasons for the dependence of the OTR values on the surface species were explored.
基金the National Natural Science Foundation of China for financial support(No.81373335)
文摘A cationic gene delivery vector, guanidinylated disulfide-containing poly(amido amine)(CARCBA), was synthesized by Michael addition reaction between N,N′-cystaminebisacrylamide(CBA) and guanidine hydrochloride(CAR). Gel permeation chromatography(GPC) was used to evaluate the molecular weight of synthesized CAR-CBA. Polyethyleneimine(PEI) with molecular weight of 25 kDa was adopted as a reference, and polyethylene glycols(PEG) with different molecular weights were used to establish a standard curve for determining the molecular weight of CAR-CBA. The effects of two critical factors, namely columns and eluents,on the molecular weight measurement of CAR-CBA were investigated to optimize the GPC quantitative method. The results showed that Ultrahydrogel columns(120, 250) and HAc–NaAc(0.5 M, pH 4.5) buffer solution were the optimal column and GPC eluent, respectively.The molecular weight of the synthesized CAR-CBA was analyzed by the optimized GPC method and determined to be 24.66 kDa.
基金The project was supported by the National Natural Science Foundation of China(Grant 50171073).
文摘In order to improve the surface hardness and wear resistance of Ti and Ti alloy components, an oxygen permeation treatment (OPT) was developed. The oxygen permeation behaviors of three Ti alloys, TA2, TB5 and TC11, treated in air with O-P medium at high temperature have been studied. The results show that the 0-P treatment can significantly improve the surface hardness of Ti alloys. The oxidation mass-gain of β-Ti alloy (TB5) is much higher than α-Ti alloy (TA2) under the same condition, while α+β Ti alloy (TC11) is the lowest. All the Ti alloys treated at this condition produce two surface layers: the outer layer consists mainly of TiO2, as well as trace of other oxides, and the inner layer consists of a Ti-O interstitial solid solution formed by the diffusion of oxygen in α crystal lattice. Thick scales of β Ti alloy (TB5) are easily formed depending mainly on the poor solid solution content of oxygen, while deep solution layer can be formed since partial β phase has been transformed into α phase. The scales of α-β Ti alloy (TC11) are very thin and compact. Aluminum-rich zone, as well as deficient zone, is found in oxide layers. A crystallographic characterization of oxygen solution layer has been performed and evaluated by crystallographic lattice constant.
基金supported by the Natural Science Foundation of Zhejiang Province,China(No.LY17C200009)the Foundation of Zhejiang Educational Committee(No.Y201328477)
文摘A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 steroid hormones were extracted from the tissues with diethyl ether.Differing from other common purification methods,the extract solutions were cleaned by gel permeation chromatography(GPC) using ethyl acetate-cyclohexane solution(1:1,v/v) as the mobile phase.The separation of target compounds was carried out by a BEH C18 column and a gradient elution consisting of acetonitrile and 0.2% aqueous formic acid(v/v).The compounds were detected under the multiple reaction monitoring(MRM) mode and quantified with external standard method.This method was validated with respect to linearity,specificity,accuracy and precision.A linearity with correlation coefficient larger than 0.995 was achieved in the range of 0.5 to 50 ng m L^(-1).The average recoveries at the spiked levels of 1.0,5.0,and 10.0 μg kg^(–1) varied between 81.7% and 90.8%,with the relative standard deviations(n=5) ranged from 3.50% to 10.0%.The limit of quantification(LOQ) for 8 steroid hormones ranged from 0.2 to 1.5 μg kg^(-1).It was concluded that this method can be successfully applied for the determination of 8 steroid hormones in complicated matrices including high-fat fish tissues.
文摘The effect of pulse frequency and current density on the effectiveness ofbiphasic pulse electrocleaning is discussed. Moderate frequency (5Hz) is found to be more effectivethan lower or higher frequency on steel surface cleanliness. A novel interpretation of cyclicvoltammagrams is used to estimate the surface cleanliness. This correlates very well with XPSdetermination of surface carbon levels. This result is discussed in terms of mechanisms ofelectrocleaning. Moderate frequency (5-10Hz) is more effective than lower frequency for inhibitinghydrogen permeation. This method can prevent hydrogen brittleness on the electrocleaninghigh-strength steel.
文摘New polyoxometalate α-K 12H 3[Y(BW 11O 39) 2]·25H 2O was synthesized and treated by high temperature gaseous rare earth permeation to prepare tungsten bronze K 0.475WO 3. XRD, TG-DTA, XPS, 183W-NMR,CV and AC impedance spectra were used to characterize the resulting material. The results of XPS indicate that La has permeated and diffused into the body of the sample and exists in the forms of binding with other components. The crystal structure parameters of K 0.475WO 3 were obtained by the analysis of XRD, which shows tetragonal crystal system with lattice parameters: a=12 28 nm, c=3.833 nm, V=578.48 nm -3. The conductivities calculated from the results of AC impedance spectra of the material increase with the increasing of temperature, which shows a semiconductor character.
基金National Natural Science Foun-dation of China(No:30973654 and No:81173007).
文摘Transdermal drug delivery has been accepted as a potential non-invasive route of drug administration,with advantages of prolonged therapeutic action,decreased side effect,easy use and better patient compliance.However,development of transdermal products is primarily hindered by the low permeability of the skin.To overcome this barrier effect,numerous new chemicals have been synthesized as potential permeation enhancers for transdermal drug delivery.In this review,we presented an overview of the investigations in this field,and further implications on selection or design of suitable permeation enhancers for transdermal drug delivery were also discussed.
基金supported by the National Natural Science Foundation of China(51004069)the National Science Fund for Distinguished Young Scholars(51225401)+1 种基金China Postdoctoral Science Foundation(201104254)the Innovation Program of Shanghai Municipal Education Commission and Shanghai University(14YZ013 and SDCX2012002)
文摘Ba0.9R0.1Co0.TFe0.225Ta0.07503-δ （BRCFT, R = Ca, La or Sr） membranes were synthesized by a solid-state reaction. Metal cation Ca2＋, La3＋ or Sr2＋ doping on A-site partially substituted Ba2＋ in BaCoo.TFe0.225Ta0.07503-δ oxides, and its subsequent effects on phase structure stability, oxygen permeability and oxygen desorption were systematically investigated by XRD, TG-DSC, Hz-TPR, O2-TPD techniques and oxygen permeation experiments. The partial substitution with Ca2＋, La3＋ or Sr2＋, whose ionic radii are smaller than that of Ba2＋, succeeded in stabilizing the cubic perovskite structure without formation of impurity phases, as revealed by XRD analysis. Oxygen-involving experi- ments showed that BRCFT with A-site fully occupied by Ba2＋ exhibited good oxygen permeation flux under He flow, reaching about 2.3 mL.min-l .cm-2 at 900 with I mm thickness. Of all the membranes, BLCFT membrane showed better chemical stability in CO2, owing to the reduction in alkalinity of the mixed conductor oxide by La doping. In addition, we also found the stability of the perovskite structure under reducing atmospheres was strengthened by increasing the size of A-site cation （Ba2＋〉La3＋〉SrZ＋〉Ca2＋）.
基金Supported by the Joint Funds of NSFC-Guangdong （U0834004）, the National Natural Science Foundation of China （20976057） and the Natural Science Foundation of Guangdong Province （06025657）.
文摘Zr-substituted,Tm-doped SrCeO3（SrCe0.95-xZrxTm0.05O3-δ,0≤x≤0.40）were synthesized via citrate complexing method,and the membranes of SrCe0.95-xZrxTm0.05O3-δwere prepared by pressing followed by sintering. X-ray diffraction（XRD）was used to characterize the phase structure of sintered membrane.The microstructure of the sintered membranes was studied by scanning electron microscopy（SEM）.Protonic and electronic conductivities were measured under different circumstance.Hydrogen permeation through the SrCe0.75Zr0.20Tm0.05O3-δmembranes was carried out using gas permeation setup.Hydrogen permeation fluxes（ 2H J）of the SrCe0.75Zr0.20Tm0.05O3-δ membrane reach up to 0.042 ml·min^ -1 ·cm^-2 at H 2 partial pressure of 0.4×10 ^5 Pa at 900°C.The hydrogen permea- tion fluxes（ 2H J）obtained in this paper are slightly lower than that of SrCe0.95Tm0.05O3-δon the same orders,and Zr doping can increase chemical stability of the SrCe0.75Zr0.20Tm0.05O3-δmembranes.
基金The authors are grateful to Dr. Shane Roark (Eltron Research Inc.) and Mr. Jinwang Yan for beneficial discussion and suggestions. We would also like to acknowledge financial support from the Ministry of Science and Technology China (Grant No. G19990
文摘The electrical conduction properties of dense BaCe0.9Mn0.1O3-d (BCM10) membrane were investigated in the temperature range of 600-900oC. High ionic and electronic conductivities at elevated temperatures make BCM10 a potential ceramic material for hydrogen separation. Hydrogen permeation through BCM10 membranes was studied using a high- temperature permeation cell. Little hydrogen could be detected at the sweep side. However, appreciable hydrogen can permeate through BCM10 membrane coated with porous platinum black, which shows that the process of hydrogen permeation through BCM10 membranes was controlled by the catalytic decomposition and recomposition of hydrogen on the surfaces of BCM10 membranes.
