HailongS. acus Linnaeus was chosen as the experimental material in the experiments and changes of cell morphology, forming rate of clone and changes of division index were conducted to identify the inhibiting effects ...HailongS. acus Linnaeus was chosen as the experimental material in the experiments and changes of cell morphology, forming rate of clone and changes of division index were conducted to identify the inhibiting effects of Hailong extract on human tumor cell lines (GLT-82). Four days after medication, most of the cells changed their normal morphology of tumor cells and became round, broken and even broke into pieces. The inhibiting rates could reach 75.1% on the fourth day. The division index reduced strongly and the clone could not form or the forming rate was very low. With the extract concentration increasing and the time prolonging, the inhibiting effect increased. These results indicate that Hailong has striking anti-tumor effects and will have a perfect future in the fields of treatment and prevention of cancer.展开更多
The inhibition effect of rare earths on the production of ·O - 2 produced by radiolysis of aqueous sodium formate saturated with O 2 with high energy pulse electron beam was studied. The result indicates ...The inhibition effect of rare earths on the production of ·O - 2 produced by radiolysis of aqueous sodium formate saturated with O 2 with high energy pulse electron beam was studied. The result indicates that rare earth nitrate obviously inhibits the production of ·O - 2 . The inhibition rate is between 28 6% and 92%. The inhibition effect increases with the increase of rare earth nitrates concentration. The distinguish dose effect relationship was observed.展开更多
Bensulfuron-Methyl(BSM)is a highly active sul-fonylurea herbicide that effectively controls most an-nual and perennial broadleaf or sedge weeds in paddyfield.However,the activity of BSM is affected byseveral evironmen...Bensulfuron-Methyl(BSM)is a highly active sul-fonylurea herbicide that effectively controls most an-nual and perennial broadleaf or sedge weeds in paddyfield.However,the activity of BSM is affected byseveral evironmental factors.Using corn seedlings asmaterial,we found that under different temperatures展开更多
[Objectives] To explore the inhibitory effect of octadecadienoic acid (ODA) on proliferation and apoptosis of glioma cells and its mechanism. [Methods] Cultured human glioma cells (cell density 2×10^(6) cells/L) ...[Objectives] To explore the inhibitory effect of octadecadienoic acid (ODA) on proliferation and apoptosis of glioma cells and its mechanism. [Methods] Cultured human glioma cells (cell density 2×10^(6) cells/L) were divided into three groups: solvent control group (DMSO, 30 μL/L), 5-FU group (10 mg/L) and octadecadienoic acid group (0.3, 0.6, 1.2 mg/L). The toxic effects of ODA on glioma cells were detected by trypan blue and thiazolium blue (MTT). The expression of P53, PI3K, P21, PKB/Akt and caspase-9 protein in glioma cells were detected by enzyme-linked immunosorbent assay (ELISA). [Results] The cell count under optical microscope showed that the inhibition rate of cell proliferation in low, medium and high dose ODA groups and 5-FU group was significantly higher than that in solvent control group ( P <0.01), but there was no significant difference compared with 5-FU group ( P >0.05). The results of MTT showed that compared with the solvent control group, the inhibition rate of cell proliferation in low, medium and high dose ODA groups and 5-FU group significantly increased ( P <0.01);compared with 5-FU group, the inhibition rate of cell proliferation in high dose ODA group significantly increased ( P <0.01). The results of flow cytometry showed that compared with the solvent control group, the number of cells in G_(0)/G_(1) phase increased significantly ( P <0.05, P <0.01), the number of cells in G_(2)/M phase decreased significantly ( P <0.01) and the apoptosis rate increased significantly ( P <0.01) in the low, medium and high dose ODA groups and 5-FU group;compared with 5-FU group, the number of cells in G_(2)/M phase decreased significantly ( P <0.01) and the apoptosis rate increased significantly ( P <0.01) in ODA group. ELISA testing results showed that the expression levels of P53, P13K and PKB/Akt in low, medium and high dose ODA groups and 5-FU group were significantly lower than those in solvent control group ( P <0.01), and only the expression level of protein in high dose ODA group was significantly lower than that in 5-FU group ( P <0.01);the expression levels of P21 and caspase-9 in low, medium and high dose ODA groups and 5-FU group were significantly higher than those in solvent control group ( P <0.05, P <0.01), but the expression level of protein in high dose ODA group was significantly higher than that in 5-FU group ( P <0.01). [Conclusions] ODA can obviously inhibit the proliferation of glioma cells and induce apoptosis. The mechanism is related to up-regulation of P21, caspase-9, down-regulation of P53, PI3K, PKB/Akt, inhibition of cell division cycle and decrease of PI3K-Akt signal transduction pathway.展开更多
[Objective] The study aimed to study the antifungal activity of biocontrol strains against Alternaria mali,colonization ability in apple leaves and the impact of some chemical fungicides on biocontrol strains were als...[Objective] The study aimed to study the antifungal activity of biocontrol strains against Alternaria mali,colonization ability in apple leaves and the impact of some chemical fungicides on biocontrol strains were also studied.[Method] Healthy leaves of Matsumotokin were collected to conduct vitro leaf test,colonization test and influence test of different fungicides on biocontrol strains.[Result] Vitro leaf test showed that B.subtilis BS-315 had strong inhibition effect on A.mali,when biocontrol strain was daubed on leaves,and pathogen was inoculated after 1 d,the inhibition effect of BS-315 against A.mali was over 90% after 3 d.BS-315 could colonize in leaves of Matsumotokin,colonization volume reached the maximum after inoculation for 3 d.Azoxystrobin and polyoxin had certain promoting effect on the growth of BS-315,while carbendazim and propiconazole completely inhibited the growth of BS-315.[Conclusion] This study would provide theoretical basis for development and rational utilization of biocontrol preparations.展开更多
The thermochemical kinetics of the rare earth ternary complex Sm(Gly) 4Im(ClO 4) 3·2H 2O (Gly glycine, Im imidazole) reacting with microbes (escherichia coli, bacillus subilis, staphylococcus aureus) was st...The thermochemical kinetics of the rare earth ternary complex Sm(Gly) 4Im(ClO 4) 3·2H 2O (Gly glycine, Im imidazole) reacting with microbes (escherichia coli, bacillus subilis, staphylococcus aureus) was studied by means of Calvet microcalorimeter. The rate constant k of microbe growth was calculated, and the inhibition effect of these complexes to microbes was compared.展开更多
MALDI-TOF-MS technology was used for identification of lipopeptide antibiotics producedby GEB3 strain, a derivative of Bacillus subtilis 168 which was transformed by lpaB3gene. The result showed GEB3 only produced lip...MALDI-TOF-MS technology was used for identification of lipopeptide antibiotics producedby GEB3 strain, a derivative of Bacillus subtilis 168 which was transformed by lpaB3gene. The result showed GEB3 only produced lipopeptide antibiotic surfactin. The analysisby LC-MS demonstrated that GEB3 produced standard surfactin isoforms with side chainlengths of 13,14 and 15 carbon atoms. The bioactivity detection of surfactin indicatedthat the surfactin produced by GEB3 had inhibition effect on plant pathogens Rhizoctoniasolani and Pyricularia oryzae.展开更多
The phenyl and methyl phenyl free radicals,formed in the oxidation-hydrolysis process of N’-acyl-N-phenylhydrazine, have been studied by ESR spectrometry.It was found that the free radical is the chief cause which pr...The phenyl and methyl phenyl free radicals,formed in the oxidation-hydrolysis process of N’-acyl-N-phenylhydrazine, have been studied by ESR spectrometry.It was found that the free radical is the chief cause which produces the feed-back inhibition effect in the hydrazine-promoted infectious development of silver halide.展开更多
The irregular defects and residual tumor tissue after surgery are challenges for effective breast cancer treatment.Herein,a smart hydrogel with self-adaptable size and dual responsive cargos release was fabricated to ...The irregular defects and residual tumor tissue after surgery are challenges for effective breast cancer treatment.Herein,a smart hydrogel with self-adaptable size and dual responsive cargos release was fabricated to treat breast cancer via accurate tumor elimination,on-demand adipose tissue regeneration and effective infection inhibition.The hydrogel consisted of thiol groups ended polyethylene glycol(SH-PEG-SH)and doxorubicin encapsulated mesoporous silica nanocarriers(DOX@MSNs)double crosslinked hyaluronic acid(HA)after loading of antibacterial peptides(AP)and adipose-derived stem cells(ADSCs).A pH-cleavable unsaturated amide bond was pre-introduced between MSNs and HA frame to perform the tumor-specific acidic environment dependent DOX@MSNs release,meanwhile an esterase degradable glyceryl dimethacrylate cap was grafted on MSNs,which contributed to the selective chemotherapy in tumor cells with over-expressed esterase.The bond cleavage between MSNs and HA would also cause the swelling of the hydrogel,which not only provide sufficient space for the growth of ADSCs,but allows the hydrogel to fully fill the irregular defects generated by surgery and residual tumor atrophy,resulting in the on-demand regeneration of adipose tissue.Moreover,the sustained release of AP could be simultaneously triggered along with the size change of hydrogel,which further avoided bacterial infection to promote tissue regeneration.展开更多
All-solid-state lithium-sulfur(Li-S)battery is regarded as next-generation high energy density and safety battery system.The key challenge is to develop a compatible high-performance solid-state electrolyte.Herein,a t...All-solid-state lithium-sulfur(Li-S)battery is regarded as next-generation high energy density and safety battery system.The key challenge is to develop a compatible high-performance solid-state electrolyte.Herein,a two birds with one stone strategy is proposed to simultaneously enhance Li+conductivity and polysulfide adsorptivity of poly(ethylene oxide)(PEO)-based polymer electrolyte via the integration of Nb_(2)CT_(x)MXene.Moreover,the sheet size of Nb_(2)CT_(x)MXene is crucial for the enhancement of Li^(+)conductivity and polysulfide adsorptivity,attributing to the difference in a specific surface area related to the percolation effect.By tuning the sheet size of Nb_(2)CT_(x)MXene from 500-300 nm to below 100 nm,the ionic conductivity of the PEO electrolyte is increased to2.62×10^(-4)S·cm^(-1)with improved Li+transference number of 0.37 at 600C.Furthermore,theoretical calculation and X-ray photoelectron spectroscopy(XPS)conjointly prove that poly sulfides could be effectively adsorbed by Nb2CTxnanosheets via forming Nb-S bonding to inhibit their shuttle in the PEO framework.As a result,the all-solid-state Li-S cell exhibits an initial capacity of 1149 mAh·g^(-1)at 0.5C and good cycling stability with 491 mAh·g^(-1)after 200 cycles.The results demonstrate the necessity of polysulfide inhibition and the application of Nb_(2)CT_(x)MXene in PEO-based electrolytes for all-solid-state Li-S batteries.展开更多
The protection of rusted carbon steel in acid corrosion environments is of great significance for equipment to keep safe operation.In this work,we presented a method to protect the rusted steel by ru st conversion tre...The protection of rusted carbon steel in acid corrosion environments is of great significance for equipment to keep safe operation.In this work,we presented a method to protect the rusted steel by ru st conversion treatment and epoxy coating.Tannic acid was selected as rust conversion agent.Tannic acid,D-limonene and nano-ZrO_(2)were used to improve the corrosion resistance of epoxy coatings.The Raman spectra,Xray diffraction and 3 D confocal images were used to characterize the rust conversion reaction.Ad hesion test showed that the loss of wet adhesion of the optimal coating was relatively low due to the addition of tannic acid,limonene and nano-ZrO(2).The corrosion resistance of five different coatings was investigated by scanning electron microscopy(SEM)and electrochemical analysis.Results show that after 264 h acid immersion,the low frequency resistance of the optimal coating consisting of rust conversion treatment and additives is 10^(7)Ωcm^(2),three orders magnitude higher than that of the pristine coating.Moreover,SEM indicates that the optimal coating possesses a smooth surface and an unbroken interface between substrate and coating.Accordingly,the corrosion-resistant mechanism of the hybrid coating is proposed.展开更多
In this work,a series of molybdovanadophosphoric heteropoly acid quaternary ammonium salts H_(3+x)PMo_(12 -x)V_xO40-T were synthesized and employed as a reaction inhibitor in the selfpolymerization of methyl meth...In this work,a series of molybdovanadophosphoric heteropoly acid quaternary ammonium salts H_(3+x)PMo_(12 -x)V_xO40-T were synthesized and employed as a reaction inhibitor in the selfpolymerization of methyl methacrylate(MMA).The polymerization inhibition effect of H_(3+x)PMoPMo_(12 -x)V_xO40-T)with different number of vanadium atoms and reaction dosages was investigated using differential scanning calorimetry(DSC).It shows that the inhibitory effect was improved with the increasing dosages of H_(3+x)PMoPMo_(12 -x)V_xO40-T),and the polymerization inhibition was also affected by the number of vanadium atoms in the H_(3+x)PMo_(12 -x)V_xO40-T .Furthermore,cyclic voltammograms(CV)was used to probe the mechanism of the inhibition reaction with H3+xPMo12xVxO40-T.The result of CV indicates that the inhibition reaction is an oxidation–reduction reaction.H_(3+x)PMo_(12 -x)V_xO40-T can react directly with the MMA monomer radicals,which eliminated the MMA monomers,and therefore the self-polymerization of the MMA can be effectively inhibited by H_(3+x)PMo_(12 -x)V_xO40-T.展开更多
The corrosion inhibition performances of sodium silicate(Na2SiO3) and acrylamide(AM) for Q235 carbon steel in a high-concentration KCl solution(25%, mass fraction) were investigated via static mass loss method, ...The corrosion inhibition performances of sodium silicate(Na2SiO3) and acrylamide(AM) for Q235 carbon steel in a high-concentration KCl solution(25%, mass fraction) were investigated via static mass loss method, elec- trochemical measurements, scanning electron microscopy(SEM), X-ray photoelectron spectroscopy(XPS) and Auger electron spectroscopy(AES). AM shows poor inhibition performance, while Na2SiO3 exhibits a better inhibition per- formance. Moreover, the steel gains mass instead of losing mass in the presence of 0.5% Na2SiO3 and 0.5% AM, in- dicating that the corrosion is completely inhibited~ SEM analysis indicates that a compact protective film is formed on the steel surface by the combined use of inhibitors. Our results demonstrate that Na2SiO3 and AM could have a synergistic effect on steel corrosion in high concentrations of KCl. The synergistic inhibition mechanism is further conjectured by the XPS and AES analysis.展开更多
The inhibition effect of an excellent environmental-friendly corrosion inhibitor--berberine on hot-dip coated steels in the diluted HCI has been investigated by using quantum chemistry analysis, mass-loss tests, elec-...The inhibition effect of an excellent environmental-friendly corrosion inhibitor--berberine on hot-dip coated steels in the diluted HCI has been investigated by using quantum chemistry analysis, mass-loss tests, elec- trochemical measurements and scanning electron microscopy (SEM) observation. Calculation results show that berberine has a nearly planar structure with a number of active centers. The value of Mulliken charge, and the distribution of the highest occupied molecular orbital (HOMO) and the lower unoccupied molecular orbital (LUMO) imply that berberine has a good ability of electron exchange with metal surface. The test results indicate that inhibition efficiency (IE%) increases with the inhibitor concentration and the highest IE can reach 99%. Adsorption of berberine on the coating surface follows Langmuir adsorption isotherm with a single molecular layer by chemisorption.展开更多
Potassium-selenium(K-Se) batteries are a promising electrical energy storage candidate because of the cost-effectiveness and material sustainability, yet they suffer from shuttle effect, volume expansion and low powde...Potassium-selenium(K-Se) batteries are a promising electrical energy storage candidate because of the cost-effectiveness and material sustainability, yet they suffer from shuttle effect, volume expansion and low powder density. The development of Se-based cathode is an effective way to overcome the above issues. Here we designed a hollow nano-spherical Co-Fe bi-metallic selenide coated with N-doped carbon(denoted as CFS@N-C)as cathode for K-Se batteries. Bimetallic selenide is benefit to improve the conductivity of composite materials;N-doped carbon layer encapsulation effectively inhibits the dissolution of poly-selenides and relieves the volume expansion. The as-prepared K-Se battery exhibits excellent rate performance(300 mAh·g^(-1) at 1000 mA·g^(-1)) and slowcharge/ultrafast-dischargecapability(dischargeat5000 mA·g^(-1) and charge at 100 mA·g^(-1) with ultrahigh capacity of 227 mAh·g^(-1)) with Coulombic efficiency nearly 100%. In addition, the ex-situ high-resolution transmission electron microscopy(HRTEM) images reveal that the charge–discharge mechanism of CFS@N-C is K^(+) replaces the bimetal and forms K_(2)Se. The unique design in this work may provide certain directions on researching for high power density K-storage materials.展开更多
Objective To determine the effect of the phosphodiesterase-5 inhibitor sildenafil compared with placebo on exercise capacity and clinical status in HFPEF. Design Multicenter, double-blind, placebo-controlled, paralle...Objective To determine the effect of the phosphodiesterase-5 inhibitor sildenafil compared with placebo on exercise capacity and clinical status in HFPEF. Design Multicenter, double-blind, placebo-controlled, parallel-group, randomized clinical trial of 216 sta- ble outpatients with HF, ejection fraction ≥ 50%, elevated N-terminal brain-type natriuretic peptide or elevat- ed invasively measured filling pressures, and reduced exercise capacity. Participants were randomized from October 2008 through February 2012 at 26 centers in North America. Follow-up was through August 30, 2012.展开更多
ABSTRACT The intensity of antiplatelet therapy during percutaneous coronary intervention (PCI) is an important deter- minant of PCI-related ischemic complications. Cangrelor is a potent intravenous adenosine diphos...ABSTRACT The intensity of antiplatelet therapy during percutaneous coronary intervention (PCI) is an important deter- minant of PCI-related ischemic complications. Cangrelor is a potent intravenous adenosine diphosphate (ADP)- receptor antagonist that acts rapidly and has quickly reversible effects.展开更多
文摘HailongS. acus Linnaeus was chosen as the experimental material in the experiments and changes of cell morphology, forming rate of clone and changes of division index were conducted to identify the inhibiting effects of Hailong extract on human tumor cell lines (GLT-82). Four days after medication, most of the cells changed their normal morphology of tumor cells and became round, broken and even broke into pieces. The inhibiting rates could reach 75.1% on the fourth day. The division index reduced strongly and the clone could not form or the forming rate was very low. With the extract concentration increasing and the time prolonging, the inhibiting effect increased. These results indicate that Hailong has striking anti-tumor effects and will have a perfect future in the fields of treatment and prevention of cancer.
文摘The inhibition effect of rare earths on the production of ·O - 2 produced by radiolysis of aqueous sodium formate saturated with O 2 with high energy pulse electron beam was studied. The result indicates that rare earth nitrate obviously inhibits the production of ·O - 2 . The inhibition rate is between 28 6% and 92%. The inhibition effect increases with the increase of rare earth nitrates concentration. The distinguish dose effect relationship was observed.
文摘Bensulfuron-Methyl(BSM)is a highly active sul-fonylurea herbicide that effectively controls most an-nual and perennial broadleaf or sedge weeds in paddyfield.However,the activity of BSM is affected byseveral evironmental factors.Using corn seedlings asmaterial,we found that under different temperatures
基金Supported by Gansu Natural Science Foundation(21JR7RA571)Lanzhou Science and Technology Plan Project(2019-1-48)Major Project of Gansu University of Political Science and Law(GZF2021XZD06).
文摘[Objectives] To explore the inhibitory effect of octadecadienoic acid (ODA) on proliferation and apoptosis of glioma cells and its mechanism. [Methods] Cultured human glioma cells (cell density 2×10^(6) cells/L) were divided into three groups: solvent control group (DMSO, 30 μL/L), 5-FU group (10 mg/L) and octadecadienoic acid group (0.3, 0.6, 1.2 mg/L). The toxic effects of ODA on glioma cells were detected by trypan blue and thiazolium blue (MTT). The expression of P53, PI3K, P21, PKB/Akt and caspase-9 protein in glioma cells were detected by enzyme-linked immunosorbent assay (ELISA). [Results] The cell count under optical microscope showed that the inhibition rate of cell proliferation in low, medium and high dose ODA groups and 5-FU group was significantly higher than that in solvent control group ( P <0.01), but there was no significant difference compared with 5-FU group ( P >0.05). The results of MTT showed that compared with the solvent control group, the inhibition rate of cell proliferation in low, medium and high dose ODA groups and 5-FU group significantly increased ( P <0.01);compared with 5-FU group, the inhibition rate of cell proliferation in high dose ODA group significantly increased ( P <0.01). The results of flow cytometry showed that compared with the solvent control group, the number of cells in G_(0)/G_(1) phase increased significantly ( P <0.05, P <0.01), the number of cells in G_(2)/M phase decreased significantly ( P <0.01) and the apoptosis rate increased significantly ( P <0.01) in the low, medium and high dose ODA groups and 5-FU group;compared with 5-FU group, the number of cells in G_(2)/M phase decreased significantly ( P <0.01) and the apoptosis rate increased significantly ( P <0.01) in ODA group. ELISA testing results showed that the expression levels of P53, P13K and PKB/Akt in low, medium and high dose ODA groups and 5-FU group were significantly lower than those in solvent control group ( P <0.01), and only the expression level of protein in high dose ODA group was significantly lower than that in 5-FU group ( P <0.01);the expression levels of P21 and caspase-9 in low, medium and high dose ODA groups and 5-FU group were significantly higher than those in solvent control group ( P <0.05, P <0.01), but the expression level of protein in high dose ODA group was significantly higher than that in 5-FU group ( P <0.01). [Conclusions] ODA can obviously inhibit the proliferation of glioma cells and induce apoptosis. The mechanism is related to up-regulation of P21, caspase-9, down-regulation of P53, PI3K, PKB/Akt, inhibition of cell division cycle and decrease of PI3K-Akt signal transduction pathway.
基金Supported by State Apple Industry Technology System ProjectDepartment of Education Research Projects in Hebei Province(2006432)~~
文摘[Objective] The study aimed to study the antifungal activity of biocontrol strains against Alternaria mali,colonization ability in apple leaves and the impact of some chemical fungicides on biocontrol strains were also studied.[Method] Healthy leaves of Matsumotokin were collected to conduct vitro leaf test,colonization test and influence test of different fungicides on biocontrol strains.[Result] Vitro leaf test showed that B.subtilis BS-315 had strong inhibition effect on A.mali,when biocontrol strain was daubed on leaves,and pathogen was inoculated after 1 d,the inhibition effect of BS-315 against A.mali was over 90% after 3 d.BS-315 could colonize in leaves of Matsumotokin,colonization volume reached the maximum after inoculation for 3 d.Azoxystrobin and polyoxin had certain promoting effect on the growth of BS-315,while carbendazim and propiconazole completely inhibited the growth of BS-315.[Conclusion] This study would provide theoretical basis for development and rational utilization of biocontrol preparations.
文摘The thermochemical kinetics of the rare earth ternary complex Sm(Gly) 4Im(ClO 4) 3·2H 2O (Gly glycine, Im imidazole) reacting with microbes (escherichia coli, bacillus subilis, staphylococcus aureus) was studied by means of Calvet microcalorimeter. The rate constant k of microbe growth was calculated, and the inhibition effect of these complexes to microbes was compared.
基金supported by the National Nature1 Science Foundation of China(30170623)the National 863 Program of China(2001AA246013).
文摘MALDI-TOF-MS technology was used for identification of lipopeptide antibiotics producedby GEB3 strain, a derivative of Bacillus subtilis 168 which was transformed by lpaB3gene. The result showed GEB3 only produced lipopeptide antibiotic surfactin. The analysisby LC-MS demonstrated that GEB3 produced standard surfactin isoforms with side chainlengths of 13,14 and 15 carbon atoms. The bioactivity detection of surfactin indicatedthat the surfactin produced by GEB3 had inhibition effect on plant pathogens Rhizoctoniasolani and Pyricularia oryzae.
文摘The phenyl and methyl phenyl free radicals,formed in the oxidation-hydrolysis process of N’-acyl-N-phenylhydrazine, have been studied by ESR spectrometry.It was found that the free radical is the chief cause which produces the feed-back inhibition effect in the hydrazine-promoted infectious development of silver halide.
基金the National High Level Talents Special Support Plan(X.C.)the“Young Talent Support Plan”of Xi'an Jiaotong University(X.C.)+2 种基金the Natural Science Foundation of Shaanxi Province(No.2022JZ-48 to X.C.)the National Natural Science Foundation of China(No.82272141 to X.C.)the Shaanxi Provincial Key Research and Development Plan Project(No.2023-JC-QN-0260 to X.Q.).
文摘The irregular defects and residual tumor tissue after surgery are challenges for effective breast cancer treatment.Herein,a smart hydrogel with self-adaptable size and dual responsive cargos release was fabricated to treat breast cancer via accurate tumor elimination,on-demand adipose tissue regeneration and effective infection inhibition.The hydrogel consisted of thiol groups ended polyethylene glycol(SH-PEG-SH)and doxorubicin encapsulated mesoporous silica nanocarriers(DOX@MSNs)double crosslinked hyaluronic acid(HA)after loading of antibacterial peptides(AP)and adipose-derived stem cells(ADSCs).A pH-cleavable unsaturated amide bond was pre-introduced between MSNs and HA frame to perform the tumor-specific acidic environment dependent DOX@MSNs release,meanwhile an esterase degradable glyceryl dimethacrylate cap was grafted on MSNs,which contributed to the selective chemotherapy in tumor cells with over-expressed esterase.The bond cleavage between MSNs and HA would also cause the swelling of the hydrogel,which not only provide sufficient space for the growth of ADSCs,but allows the hydrogel to fully fill the irregular defects generated by surgery and residual tumor atrophy,resulting in the on-demand regeneration of adipose tissue.Moreover,the sustained release of AP could be simultaneously triggered along with the size change of hydrogel,which further avoided bacterial infection to promote tissue regeneration.
基金financially supported by the State Key Laboratory of Powder Metallurgy,Hunan Provincial Natural Science Foundation of China(No.2020JJ4107)the InnovationDriven Project of Central South University(No.2020CX037)+2 种基金the Postgraduate Scientific Research Innovation Project of Hunan Province(No.QL20220021)the National Natural Science Foundation of China(No.51802352)the Science and Technology Innovation Leading Project of High-Tech Industry of Hunan Province,China(No.2020GK2067)。
文摘All-solid-state lithium-sulfur(Li-S)battery is regarded as next-generation high energy density and safety battery system.The key challenge is to develop a compatible high-performance solid-state electrolyte.Herein,a two birds with one stone strategy is proposed to simultaneously enhance Li+conductivity and polysulfide adsorptivity of poly(ethylene oxide)(PEO)-based polymer electrolyte via the integration of Nb_(2)CT_(x)MXene.Moreover,the sheet size of Nb_(2)CT_(x)MXene is crucial for the enhancement of Li^(+)conductivity and polysulfide adsorptivity,attributing to the difference in a specific surface area related to the percolation effect.By tuning the sheet size of Nb_(2)CT_(x)MXene from 500-300 nm to below 100 nm,the ionic conductivity of the PEO electrolyte is increased to2.62×10^(-4)S·cm^(-1)with improved Li+transference number of 0.37 at 600C.Furthermore,theoretical calculation and X-ray photoelectron spectroscopy(XPS)conjointly prove that poly sulfides could be effectively adsorbed by Nb2CTxnanosheets via forming Nb-S bonding to inhibit their shuttle in the PEO framework.As a result,the all-solid-state Li-S cell exhibits an initial capacity of 1149 mAh·g^(-1)at 0.5C and good cycling stability with 491 mAh·g^(-1)after 200 cycles.The results demonstrate the necessity of polysulfide inhibition and the application of Nb_(2)CT_(x)MXene in PEO-based electrolytes for all-solid-state Li-S batteries.
基金supported financially by the Key Technology of Corrosion Control on Wind Power Equipment Academician Workstation Project(No.2013B090400023)。
文摘The protection of rusted carbon steel in acid corrosion environments is of great significance for equipment to keep safe operation.In this work,we presented a method to protect the rusted steel by ru st conversion treatment and epoxy coating.Tannic acid was selected as rust conversion agent.Tannic acid,D-limonene and nano-ZrO_(2)were used to improve the corrosion resistance of epoxy coatings.The Raman spectra,Xray diffraction and 3 D confocal images were used to characterize the rust conversion reaction.Ad hesion test showed that the loss of wet adhesion of the optimal coating was relatively low due to the addition of tannic acid,limonene and nano-ZrO(2).The corrosion resistance of five different coatings was investigated by scanning electron microscopy(SEM)and electrochemical analysis.Results show that after 264 h acid immersion,the low frequency resistance of the optimal coating consisting of rust conversion treatment and additives is 10^(7)Ωcm^(2),three orders magnitude higher than that of the pristine coating.Moreover,SEM indicates that the optimal coating possesses a smooth surface and an unbroken interface between substrate and coating.Accordingly,the corrosion-resistant mechanism of the hybrid coating is proposed.
基金supported by the Research and Development Fund for the postdoctoral researchers of Heilongjiang Province (2012)
文摘In this work,a series of molybdovanadophosphoric heteropoly acid quaternary ammonium salts H_(3+x)PMo_(12 -x)V_xO40-T were synthesized and employed as a reaction inhibitor in the selfpolymerization of methyl methacrylate(MMA).The polymerization inhibition effect of H_(3+x)PMoPMo_(12 -x)V_xO40-T)with different number of vanadium atoms and reaction dosages was investigated using differential scanning calorimetry(DSC).It shows that the inhibitory effect was improved with the increasing dosages of H_(3+x)PMoPMo_(12 -x)V_xO40-T),and the polymerization inhibition was also affected by the number of vanadium atoms in the H_(3+x)PMo_(12 -x)V_xO40-T .Furthermore,cyclic voltammograms(CV)was used to probe the mechanism of the inhibition reaction with H3+xPMo12xVxO40-T.The result of CV indicates that the inhibition reaction is an oxidation–reduction reaction.H_(3+x)PMo_(12 -x)V_xO40-T can react directly with the MMA monomer radicals,which eliminated the MMA monomers,and therefore the self-polymerization of the MMA can be effectively inhibited by H_(3+x)PMo_(12 -x)V_xO40-T.
基金Supported by the National Natural Science Foundation of China(No. 51471021).
文摘The corrosion inhibition performances of sodium silicate(Na2SiO3) and acrylamide(AM) for Q235 carbon steel in a high-concentration KCl solution(25%, mass fraction) were investigated via static mass loss method, elec- trochemical measurements, scanning electron microscopy(SEM), X-ray photoelectron spectroscopy(XPS) and Auger electron spectroscopy(AES). AM shows poor inhibition performance, while Na2SiO3 exhibits a better inhibition per- formance. Moreover, the steel gains mass instead of losing mass in the presence of 0.5% Na2SiO3 and 0.5% AM, in- dicating that the corrosion is completely inhibited~ SEM analysis indicates that a compact protective film is formed on the steel surface by the combined use of inhibitors. Our results demonstrate that Na2SiO3 and AM could have a synergistic effect on steel corrosion in high concentrations of KCl. The synergistic inhibition mechanism is further conjectured by the XPS and AES analysis.
基金supported by the Shandong Provincial Natural Science Foundation, China (No. ZR2009BQ016)the Fundamental Research Funds for the Central Universities, China (No. 12CX04055A)
文摘The inhibition effect of an excellent environmental-friendly corrosion inhibitor--berberine on hot-dip coated steels in the diluted HCI has been investigated by using quantum chemistry analysis, mass-loss tests, elec- trochemical measurements and scanning electron microscopy (SEM) observation. Calculation results show that berberine has a nearly planar structure with a number of active centers. The value of Mulliken charge, and the distribution of the highest occupied molecular orbital (HOMO) and the lower unoccupied molecular orbital (LUMO) imply that berberine has a good ability of electron exchange with metal surface. The test results indicate that inhibition efficiency (IE%) increases with the inhibitor concentration and the highest IE can reach 99%. Adsorption of berberine on the coating surface follows Langmuir adsorption isotherm with a single molecular layer by chemisorption.
基金financially supported by Hunan Provincial Natural Science Foundation of China(No.2019JJ40031)the National Natural Science Foundation of China(Nos.51922038 and 51672078)Hunan Outstanding Youth Talents(No.2019JJ20005)。
文摘Potassium-selenium(K-Se) batteries are a promising electrical energy storage candidate because of the cost-effectiveness and material sustainability, yet they suffer from shuttle effect, volume expansion and low powder density. The development of Se-based cathode is an effective way to overcome the above issues. Here we designed a hollow nano-spherical Co-Fe bi-metallic selenide coated with N-doped carbon(denoted as CFS@N-C)as cathode for K-Se batteries. Bimetallic selenide is benefit to improve the conductivity of composite materials;N-doped carbon layer encapsulation effectively inhibits the dissolution of poly-selenides and relieves the volume expansion. The as-prepared K-Se battery exhibits excellent rate performance(300 mAh·g^(-1) at 1000 mA·g^(-1)) and slowcharge/ultrafast-dischargecapability(dischargeat5000 mA·g^(-1) and charge at 100 mA·g^(-1) with ultrahigh capacity of 227 mAh·g^(-1)) with Coulombic efficiency nearly 100%. In addition, the ex-situ high-resolution transmission electron microscopy(HRTEM) images reveal that the charge–discharge mechanism of CFS@N-C is K^(+) replaces the bimetal and forms K_(2)Se. The unique design in this work may provide certain directions on researching for high power density K-storage materials.
文摘Objective To determine the effect of the phosphodiesterase-5 inhibitor sildenafil compared with placebo on exercise capacity and clinical status in HFPEF. Design Multicenter, double-blind, placebo-controlled, parallel-group, randomized clinical trial of 216 sta- ble outpatients with HF, ejection fraction ≥ 50%, elevated N-terminal brain-type natriuretic peptide or elevat- ed invasively measured filling pressures, and reduced exercise capacity. Participants were randomized from October 2008 through February 2012 at 26 centers in North America. Follow-up was through August 30, 2012.
文摘ABSTRACT The intensity of antiplatelet therapy during percutaneous coronary intervention (PCI) is an important deter- minant of PCI-related ischemic complications. Cangrelor is a potent intravenous adenosine diphosphate (ADP)- receptor antagonist that acts rapidly and has quickly reversible effects.