To date,there is no research that deals with biological waste as fillers in polyphenylene sulfide(PPS).In this study,oyster shells were recycled and treated to prepare thermally-treated oyster shells(TOS),which were u...To date,there is no research that deals with biological waste as fillers in polyphenylene sulfide(PPS).In this study,oyster shells were recycled and treated to prepare thermally-treated oyster shells(TOS),which were used as PPS fillers to make new bio-based antibacterial composite materials.The effect of varying the content of TOS was studied by means of structure and performance characterization.PPS/TOS composites were demonstrated to have an antibacterial effect on the growth of E coli and S.aureus.Qualitative analysis showed that when the TOS content was≥30%and 40%,the composite materials had an apparent inhibition zone.Quantitative analysis showed that the antibacterial activity increased with the TOS content.Fourier transform infrared spectroscopy indicated the formation of hydrogen bonds between the molecular chains of TOS and PPS and the occurrence of a coordination reaction.At 10%TOS,the composite tensile strength reached a maximum value of 72.5 MPa,which is 9.65%higher than that of pure PPS.The trend of bending properties is the same as that of tensile properties,showing that the maximum property was reached for the composite with 10%TOS.At the same time,the crystallinity and contact angle were the highest,and the permeability coefficient was the lowest.The fatigue test results indicated that for the composite with 10%TOS,the tensile strength was 23%lower than static tensile strength,and the yield strength was 10%lower than the static yield strength.The results of the study showed that TOS not only could reduce the cost of PPS,but also could impart antibacterial properties and enhance the mechanical and,barrier properties,the thermostability,as well as the crystallinity.展开更多
Using 9200 laser particle size analyzer and KYKY-2800 scanning electron microscope, particle sizes and cellular morphology of Radix Astragalus and Radix Isatidis ultrafine powders were observed. According to the resu...Using 9200 laser particle size analyzer and KYKY-2800 scanning electron microscope, particle sizes and cellular morphology of Radix Astragalus and Radix Isatidis ultrafine powders were observed. According to the results, the particle size of 89. 1 % of Radix Astragalus ultrafine powders ranged from 1.729 [xm to 44.938 |xm, Z )50 =4.368 |xm; the particle size of 93.411% of Radix Isatidis ultrafine powders ranged from 1.510 [xm to 44.938 |xm, Z )50 = 8 .7 2 6 [xm. Radix As-tragalus and Radix Isatidis ultrafine powders were pulverized completely without intact cellular morphology. The antibacterial activity of Radix Astragalus and Radix Isatidis ultrafine powders against chicken-derived E. coli (078) was investigated. The results indicated that Radix Astragalus and Radix Isatidis ultrafine powders exhibited higher antibacterial activity against chicken-derived E. coli (078 ) compared with the corresponding coarse powders. This study laid a solid foundation for the development and application of Chinese medicine ultrafine powder preparations.展开更多
Antibacterial powders of titanium dioxide/silver sulfate were produced by heat-treatment of the metatitanic acid, as precursor, into which the silver nitrate was added. The influences of heating temperature on the str...Antibacterial powders of titanium dioxide/silver sulfate were produced by heat-treatment of the metatitanic acid, as precursor, into which the silver nitrate was added. The influences of heating temperature on the structure and composition of the product were investigated through XRD and SEM. The results show that the powder is spherical in the phase of TiO2-Ag2SO4. The granularity of the particles increases from 10.7nm to 28.7nm with the temperature of heat-treatment increasing from 300℃ to 800℃. The antibacterial activity of the powder was judged in the way of the minimum inhibitory contents (MiCs). When the content of silver sulfate is less than 2%, the photocatalysis of titanium dioxide and silver ions cooperate to kill bacteria. And the MiCs decrease and keep around 1.0×10 -41.5×10 -4 constantly with the increase of silver content. Furthermore, the MiCs decrease with the increase of temperature of heat-treatment when the temperature is lower than 500℃. But when the temperature is beyond 600℃ the MiCs increase quickly, which shows the inferior antibacterial performance.展开更多
Doping titania powders were synthesized by ultrasonic spray pyrolysis method from an aqueous solution containing H2TiF6 and AgNO3.The effects of the processing parameters on particle size distribution,structure,and mo...Doping titania powders were synthesized by ultrasonic spray pyrolysis method from an aqueous solution containing H2TiF6 and AgNO3.The effects of the processing parameters on particle size distribution,structure,and morphology of doping particles were investigated.The results show that aggregation-free spherical particles with average diameter of 200-600 nm are obtained and the particle size of the powder can be controlled by adjusting the concentration of solution.The experimental approach indicates that the size and the value of standard deviation of particle size increase from 210 nm to 450 nm and from 0.46 to 0.73 respectively with the increase of the titanic ion concentration from 0.05 to 0.4 mol/L.Composite TiOF2 is obtained when the pyrolysis temperature is set to be 400 ℃.With increasing pyrolysis temperature from 400 ℃ to 800 ℃,the crystal size of titania powders increases from 14.1 to 26.5 nm and TiOF2 content of powder decreases dramatically.The property of ion released from powder is affected significantly by the pyrolysis temperature,and the amount of fluorine ion and silver ion released from powder decrease with increasing pyrolysis temperature.The optical property of doping titania powders is not affected by pyrolysis temperature.Antibacterial test results show that composite powders containing more fluorine ions exhibit stronger antibacterial activity against E.coli.展开更多
Objective: To explore the effects of the extract of Sanchen powder(ESCP) combined with vancomycin on methicillin-resistant Staphylococcus aureus(MRSA) planktonic cells, biofilms, and virulence factors.Methods: The her...Objective: To explore the effects of the extract of Sanchen powder(ESCP) combined with vancomycin on methicillin-resistant Staphylococcus aureus(MRSA) planktonic cells, biofilms, and virulence factors.Methods: The herbs in Sanchen powder(SCP) were extracted separately with 50% ethanol. Then, the content of hydroxysafflower yellow A(HSYA) and cholic acid in the extract of artificial cattle bezoar(artificial Calculus bovis) and safflower(Carthamus tinctorius L.) was measured by ultraviolet visible-vis spectrophotometry and high-performance liquid chromatography. The effects of ESCP combined with vancomycin on MRSA by observing its biofilm viability were assessed using a 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium5-carboxanilide reduction assay and scanning electron microscopy.Additionally, enzyme activity was measured by plasma coagulase test and DNase test.Results: The cholic acid content of the artificial C. bovis extract was 7.34(0.81) mg/g, and the HSYA content of the C. tinctorius extract was 9.18(0.09) mg/g. The minimal inhibitory concentrations of ESCP and vancomycin were 25.6 mg/m L and 2 μg/m L. The minimum bactericidal concentration of ESCP was51.2 mg/m L. ESCP combined with vancomycin could inhibit the expression of coagulase and bacteria in mature biofilms. Neither ESCP nor vancomycin had a significant effect on DNase.Conclusion: This study is the first to show that ESCP combined with vancomycin inhibits coagulase and MRSA embedded in mature biofilms and that it represents a promising treatment for MRSA infection.展开更多
基金Sichuan Province Science and Technology Support Program (2022JDTD0016,2020YFG0176)Chengdu Science and Technology (2021-RC02-00005-CG)+5 种基金Sichuan Golden-Elephant Sincerity Chemical Co.,Ltd (HX2020019)Zigong City Science and Technology (2019CXRC01,2020YGJC13)Opening Project of Material Corrosion and Protection Key Laboratory of Sichuan Province (2019CL05,2020CL19,2018CL07)Opening Project of Sichuan Province,the Foundation of Introduced Talent of Sichuan University of Science and Engineering (2017RCL16,2019RC05,2019RC07,2020RC16)the Opening Project of Key Laboratories of Fine Chemicals and Surfactants in Sichuan Provincial Universities (2020JXY04)Xi’an Weijingyi Art and Culture Communication Co.,Ltd (HX2021385)。
文摘To date,there is no research that deals with biological waste as fillers in polyphenylene sulfide(PPS).In this study,oyster shells were recycled and treated to prepare thermally-treated oyster shells(TOS),which were used as PPS fillers to make new bio-based antibacterial composite materials.The effect of varying the content of TOS was studied by means of structure and performance characterization.PPS/TOS composites were demonstrated to have an antibacterial effect on the growth of E coli and S.aureus.Qualitative analysis showed that when the TOS content was≥30%and 40%,the composite materials had an apparent inhibition zone.Quantitative analysis showed that the antibacterial activity increased with the TOS content.Fourier transform infrared spectroscopy indicated the formation of hydrogen bonds between the molecular chains of TOS and PPS and the occurrence of a coordination reaction.At 10%TOS,the composite tensile strength reached a maximum value of 72.5 MPa,which is 9.65%higher than that of pure PPS.The trend of bending properties is the same as that of tensile properties,showing that the maximum property was reached for the composite with 10%TOS.At the same time,the crystallinity and contact angle were the highest,and the permeability coefficient was the lowest.The fatigue test results indicated that for the composite with 10%TOS,the tensile strength was 23%lower than static tensile strength,and the yield strength was 10%lower than the static yield strength.The results of the study showed that TOS not only could reduce the cost of PPS,but also could impart antibacterial properties and enhance the mechanical and,barrier properties,the thermostability,as well as the crystallinity.
基金Oupported by Spark Program of the Ministry of Science and Technology of China(2015GA620002)Science and Technology Support Program of Science and Technology Department of Hebei Province(12220408D,14966610D)+2 种基金Post-award Grant Program from the Department of Science and Technology of Hebei Province(15926620H)Project of Shijiazhuang Municipal Science and Technology Bureau(141200603A)Project of Chengde Municipal Science and Technology Bureau(2015N0001)
文摘Using 9200 laser particle size analyzer and KYKY-2800 scanning electron microscope, particle sizes and cellular morphology of Radix Astragalus and Radix Isatidis ultrafine powders were observed. According to the results, the particle size of 89. 1 % of Radix Astragalus ultrafine powders ranged from 1.729 [xm to 44.938 |xm, Z )50 =4.368 |xm; the particle size of 93.411% of Radix Isatidis ultrafine powders ranged from 1.510 [xm to 44.938 |xm, Z )50 = 8 .7 2 6 [xm. Radix As-tragalus and Radix Isatidis ultrafine powders were pulverized completely without intact cellular morphology. The antibacterial activity of Radix Astragalus and Radix Isatidis ultrafine powders against chicken-derived E. coli (078) was investigated. The results indicated that Radix Astragalus and Radix Isatidis ultrafine powders exhibited higher antibacterial activity against chicken-derived E. coli (078 ) compared with the corresponding coarse powders. This study laid a solid foundation for the development and application of Chinese medicine ultrafine powder preparations.
文摘Antibacterial powders of titanium dioxide/silver sulfate were produced by heat-treatment of the metatitanic acid, as precursor, into which the silver nitrate was added. The influences of heating temperature on the structure and composition of the product were investigated through XRD and SEM. The results show that the powder is spherical in the phase of TiO2-Ag2SO4. The granularity of the particles increases from 10.7nm to 28.7nm with the temperature of heat-treatment increasing from 300℃ to 800℃. The antibacterial activity of the powder was judged in the way of the minimum inhibitory contents (MiCs). When the content of silver sulfate is less than 2%, the photocatalysis of titanium dioxide and silver ions cooperate to kill bacteria. And the MiCs decrease and keep around 1.0×10 -41.5×10 -4 constantly with the increase of silver content. Furthermore, the MiCs decrease with the increase of temperature of heat-treatment when the temperature is lower than 500℃. But when the temperature is beyond 600℃ the MiCs increase quickly, which shows the inferior antibacterial performance.
基金Project(04GK2007) supported by the Key Project of Scientific and Technological Department of Hunan Province, China
文摘Doping titania powders were synthesized by ultrasonic spray pyrolysis method from an aqueous solution containing H2TiF6 and AgNO3.The effects of the processing parameters on particle size distribution,structure,and morphology of doping particles were investigated.The results show that aggregation-free spherical particles with average diameter of 200-600 nm are obtained and the particle size of the powder can be controlled by adjusting the concentration of solution.The experimental approach indicates that the size and the value of standard deviation of particle size increase from 210 nm to 450 nm and from 0.46 to 0.73 respectively with the increase of the titanic ion concentration from 0.05 to 0.4 mol/L.Composite TiOF2 is obtained when the pyrolysis temperature is set to be 400 ℃.With increasing pyrolysis temperature from 400 ℃ to 800 ℃,the crystal size of titania powders increases from 14.1 to 26.5 nm and TiOF2 content of powder decreases dramatically.The property of ion released from powder is affected significantly by the pyrolysis temperature,and the amount of fluorine ion and silver ion released from powder decrease with increasing pyrolysis temperature.The optical property of doping titania powders is not affected by pyrolysis temperature.Antibacterial test results show that composite powders containing more fluorine ions exhibit stronger antibacterial activity against E.coli.
基金supported by the Scientific Research and Development Fund of the Beijing University of Chinese Medicine(2180072120047)by the Tibetan medicine Collaborative Innovation Fund (5040071620003)
文摘Objective: To explore the effects of the extract of Sanchen powder(ESCP) combined with vancomycin on methicillin-resistant Staphylococcus aureus(MRSA) planktonic cells, biofilms, and virulence factors.Methods: The herbs in Sanchen powder(SCP) were extracted separately with 50% ethanol. Then, the content of hydroxysafflower yellow A(HSYA) and cholic acid in the extract of artificial cattle bezoar(artificial Calculus bovis) and safflower(Carthamus tinctorius L.) was measured by ultraviolet visible-vis spectrophotometry and high-performance liquid chromatography. The effects of ESCP combined with vancomycin on MRSA by observing its biofilm viability were assessed using a 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium5-carboxanilide reduction assay and scanning electron microscopy.Additionally, enzyme activity was measured by plasma coagulase test and DNase test.Results: The cholic acid content of the artificial C. bovis extract was 7.34(0.81) mg/g, and the HSYA content of the C. tinctorius extract was 9.18(0.09) mg/g. The minimal inhibitory concentrations of ESCP and vancomycin were 25.6 mg/m L and 2 μg/m L. The minimum bactericidal concentration of ESCP was51.2 mg/m L. ESCP combined with vancomycin could inhibit the expression of coagulase and bacteria in mature biofilms. Neither ESCP nor vancomycin had a significant effect on DNase.Conclusion: This study is the first to show that ESCP combined with vancomycin inhibits coagulase and MRSA embedded in mature biofilms and that it represents a promising treatment for MRSA infection.