Carbonaceous catalysts are potential alternatives to metal catalysts. Graphene has been paid much attention for its high surface area and light weight. Here, hydrogenated graphene has been prepared by a simple gamma r...Carbonaceous catalysts are potential alternatives to metal catalysts. Graphene has been paid much attention for its high surface area and light weight. Here, hydrogenated graphene has been prepared by a simple gamma ray irradiation of graphene oxide aqueous suspension at room temperature. Transmission electron microscopic, element analysis, X-ray photoelectron spectroscopy, and UV-Vis spectrophotometer studies verified the hydrogenation of graphene. The as-prepared hydrogenated graphene can be used as a metal-free carbonaceous catalyst for the Fenton-like degradation of organic dye in water.展开更多
Alkali metal(Li, Na, K) doped ZnO powders were synthesized by solid-state reaction at different calcination temperatures and holding time. Effects of holding time and K sources on the infrared emissivity of ZnO were i...Alkali metal(Li, Na, K) doped ZnO powders were synthesized by solid-state reaction at different calcination temperatures and holding time. Effects of holding time and K sources on the infrared emissivity of ZnO were investigated. The structure and surface morphologies of samples were characterized by X-ray diffraction(XRD) and scanning electron microscopy(SEM). The UV-Vis absorption and infrared emissivities were investigated by a UV-Vis spectrophotometer and an infrared emissometer, respectively. XRD patterns confirm the wurtzite structure of the as prepared samples with single phase. Smooth grain surfaces are detected in all doped ZnO samples, while ZnO:Li and ZnO:Na present the aggregation of grains. The redshifts in the optical band-gap are observed in K-, Na-, and Li-doped ZnO with the values 3.150, 3.144, and 3.142 eV. Due to better crystalline quality, ZnO:K shows a lower emissivity than others. The emissivity of K-doped ZnO decreases to the minimum value(0.804), at 1200 °C and holding 2 h. Compared with KNO3 as K source, K2CO3 doped ZnO has lower emissivities.展开更多
With rutin standard sample as the comparison, flavonoid extraction rate as an indicator, UV-2450 ultraviolet visible light spectrophotometer to measure flavonoid content in planted Trollius chinensis through orthogona...With rutin standard sample as the comparison, flavonoid extraction rate as an indicator, UV-2450 ultraviolet visible light spectrophotometer to measure flavonoid content in planted Trollius chinensis through orthogonal experiment, this experiment optimizes process condition of flavonoid in Trollius chinensis through water extraction and ethanol extraction. The result shows that flavonoid extraction rate of Trollius chinensis through ethanol extraction method is obviously higher than water extraction, and the optimal extraction process condition is： ethanol concentration is 75%, extraction time is 90min, extraction times are 3, and fluid material ratio is 20：1.展开更多
TiO2/bauxite-tailings （TiO2/BTs） composites were prepared via a chemical liquid deposition method and characterized by X-ray diffractometry （XRD）, scanning electronic microscopy （SEM） and N2 adsorption analysis....TiO2/bauxite-tailings （TiO2/BTs） composites were prepared via a chemical liquid deposition method and characterized by X-ray diffractometry （XRD）, scanning electronic microscopy （SEM） and N2 adsorption analysis. The photocatalytic performance of TiO2/BTs composites was evaluated with UV-Vis spectrophotometer following the changes of phenol concentration under different illumination time. Effects of the calcination temperature, the pH and the cycles on the photocatalytic activity of TiO2/BTs composites were investigated. The composites calcined at 500 and 600 ℃ exhibit the best photocatalytic performance, and the phenol degradation ratios reacting for 40 and 160 rain reach 35% and 78% respectively under the same conditions, higher than those of 29% and 76% of the Degussa P25（TiO2）. The ability of TiO2/BTs500 （BTs500 represents bauxite-tailings calcined at 500 ℃） composites to degrade phenol increases with decreasing pH.展开更多
The mixed P3HT （poly（3-hexylthiophene）） and [6,6]-PCBM （phenyl C61-butyric acid methyl ester） organic thin films were investigated for electronic structure using UV-Vis spectrophotometer and PESA （photo-electro...The mixed P3HT （poly（3-hexylthiophene）） and [6,6]-PCBM （phenyl C61-butyric acid methyl ester） organic thin films were investigated for electronic structure using UV-Vis spectrophotometer and PESA （photo-electron spectroscopy in air）. Furthermore, ESR （electron spin resonance） and AFM （atomic force microscopy） were used to investigate the surface morphology and molecular orientation, respectively. ESR analysis indicated the molecular orientation of the P3HT crystalline in the blend thin films, which the crystalline oriented normal to the substrate with distribution of 35°. AFM images indicated that the surface morphology of P3HT film was affected by the presence of PCBM nanoparticles. Solution-processed OTFTs （organic thin-film transistors） based on P3HT/PCBM blend thin film in a top source-drain contact structure was fabricated, and the electrical characteristics of the devices were also investigated. A unipolar property with p-channel characteristics were obtained in glove box measurement.展开更多
The enzyme activities of phenylalanine ammonia-lyase from six years old Ginkgo biloba leaves in the potted orchard were induced by four groups of metal ions respectively. The PAL activities and flavonoids content were...The enzyme activities of phenylalanine ammonia-lyase from six years old Ginkgo biloba leaves in the potted orchard were induced by four groups of metal ions respectively. The PAL activities and flavonoids content were measured by the UV-Vis spectrophotometer. Changes of the whole year were also studied. The results showed that four groups of metal ion treatments had significant effects on the PAL activities and flavonoids contents in Ginkgo leaves. The treatments with 0.1% and 0.3% FeSO4, 0.1%, 0.2% and 0.3% ZnSO4, 0.1%, 0.3% and 0.5% MnSO4, 0.1% and 0.4% CuSO4 not only enhanced flavonoids contents, but also extended the optimum harvest dates of ginkgo leaves. The optimum combination was 0.1% FeSO4, 0.2% ZnSO4, 0.3% MnSO4, and 0.4% CuSO4. It could improve flavonoids content up to 1.619 4%.展开更多
The hydrophobic films of TixOy-CmHn. deposited from mixture gases of titanium isopropoxide （TTIP） and oxygen by plasma enhanced chemical vapor deposition （PECVD） were investigated. The films were investigated by s...The hydrophobic films of TixOy-CmHn. deposited from mixture gases of titanium isopropoxide （TTIP） and oxygen by plasma enhanced chemical vapor deposition （PECVD） were investigated. The films were investigated by scanning electron microscope （ SEM ）, transmission electron microscope （ TEM ）, Fourier transform infrared spectrometer （ FTIR）, X-Ray diffraction （ XRD ）, element analysis （ EA ）, ultraviolet visible spectrometer （ UV-Vis）, and water contact angle （WCA）. The results reveal that the surface of the films is formed by mierosized papillaes aggregated by inorganic and organic phases of complex nanoparticles with size from 50 nm to 200 nm when the discharge power is increased from 40 W to 150 W. All fdms demonstrate the strong broad of Ti-O-Ti stretching vibration at 400 -800cm-1, -CH bending vibration at 1 388 cm -1, and broadening -OH stretching vibration at 3 000-3500 cm-1 With the increase of the discharge power, the asdeposited film changes from amorphous to crystallization. The WCA of the film can be as high as 160°, indicating the hydrophobicity. The films show a similar ultraviolet absorption property as the bulk TiO2 film. The composition of the composition of film deposited at 150 W can be formulated as Tio.302-C1.5H3. Therefore, the composition formula of this hydrophobic film could be expressed as TiO2-C5H10O4.7. It is believed that the complex micro/nano structures of TiO2 and C5H10O4.7 residues are responsible for the observed hydrophobicity and the ultraviolet absorption property of the film.展开更多
Gallium oxide （Ga203） films were deposited on singlecrystalline sapphire （0001） substrate by radio frequency （RF） magnetron sputtering technique in the temperature range of 300--500 ℃. The microstructure of the...Gallium oxide （Ga203） films were deposited on singlecrystalline sapphire （0001） substrate by radio frequency （RF） magnetron sputtering technique in the temperature range of 300--500 ℃. The microstructure of the fl-Ga203 films were investigated in detail using X-ray diffractometer （XRD） and scanning electron microscope （SEM）. The results show that the film prepared at 500℃ exhibits the best crystallinity with a monoclinic structure （fl-Ga203）. Structure analysis reveals a clear out-of-plane orientation offl-Ga203 （201） II A1203 （0001）. The average transmittance of these films in the visible wavelength range exceeds 90%, and the optical band gap of the films varies from 4.68 eV to 4.94 eV which were measured by an ultraviolet-visible-near infrared （UV-vis-NIR） spectrophotometer. Therefore, it is hopeful that the fl-Ga203 film can be used in the UV optoelectronic devices.展开更多
Nano transparent conducting titanium-zinc oxide(Ti-Zn O) thin films were prepared on glass substrates by radio frequency(RF) magnetron sputtering technique. The deposited films are characterized by X-ray diffraction(X...Nano transparent conducting titanium-zinc oxide(Ti-Zn O) thin films were prepared on glass substrates by radio frequency(RF) magnetron sputtering technique. The deposited films are characterized by X-ray diffraction(XRD), four-probe meter and UV-visible spectrophotometer. The effects of Ti-doping content on the structural, optical and electrical properties of the films are investigated. The XRD results show that the obtained films are polycrystalline with a hexagonal wurtzite structure and preferentially oriented in the(002) crystallographic direction. The structural and optoelectronic characteristics of the deposited films are subjected to the Ti-doping content. The Ti-Zn O sample fabricated with the Ti-doping content of 3%(weight percentage) possesses the best crystallinity and optoelectronic performance, with the highest degree of preferred(002) orientation of 99.87%, the largest crystallite size of 83.2 nm, the minimum lattice strain of 6.263×10^(-4), the highest average visible transmittance of 88.8%, the lowest resistivity of 1.18×10^(-3) Ω·cm and the maximum figure of merit(FOM) of 7.08×10~3 Ω^(-1)·cm^(-1). Furthermore, the optical bandgaps of the films are evaluated by extrapolation method and observed to be an increasing tendency with the increase of the Ti-doping content.展开更多
The Cu2 Zn Sn S4(CZTS) powders are successfully synthesized by using Zn S and Cu2 Sn S3 as raw materials directly without any intermediate phase at 450 °C for 3 h in Ar atmosphere.The crystalline structure,morpho...The Cu2 Zn Sn S4(CZTS) powders are successfully synthesized by using Zn S and Cu2 Sn S3 as raw materials directly without any intermediate phase at 450 °C for 3 h in Ar atmosphere.The crystalline structure,morphology and optical properties of the CZTS powders are characterized by X-ray diffraction(XRD),Raman spectrum,field emission scanning electron microscopy(FESEM) and ultraviolet-visible(UV-vis) spectrophotometer,respectively.The results show that the band gap of the obtained CZTS is 1.53 e V.The CZTS film is fabricated by spin coating a mixture of CZTS powders and novolac resin with a weight percentage of 30%.The photoelectrical properties of such CZTS films are measured,and the results show an incident light density of 100 m W·cm-2 with the bias voltage of 0.40 V,and the photocurrent density can approach 9.80×10-5 A·cm2 within 50 s,giving an on/off switching ratio of 1.64.展开更多
文摘Carbonaceous catalysts are potential alternatives to metal catalysts. Graphene has been paid much attention for its high surface area and light weight. Here, hydrogenated graphene has been prepared by a simple gamma ray irradiation of graphene oxide aqueous suspension at room temperature. Transmission electron microscopic, element analysis, X-ray photoelectron spectroscopy, and UV-Vis spectrophotometer studies verified the hydrogenation of graphene. The as-prepared hydrogenated graphene can be used as a metal-free carbonaceous catalyst for the Fenton-like degradation of organic dye in water.
基金Project(JB141405)supported by the Fundamental Research Funds for the Central Universities of China
文摘Alkali metal(Li, Na, K) doped ZnO powders were synthesized by solid-state reaction at different calcination temperatures and holding time. Effects of holding time and K sources on the infrared emissivity of ZnO were investigated. The structure and surface morphologies of samples were characterized by X-ray diffraction(XRD) and scanning electron microscopy(SEM). The UV-Vis absorption and infrared emissivities were investigated by a UV-Vis spectrophotometer and an infrared emissometer, respectively. XRD patterns confirm the wurtzite structure of the as prepared samples with single phase. Smooth grain surfaces are detected in all doped ZnO samples, while ZnO:Li and ZnO:Na present the aggregation of grains. The redshifts in the optical band-gap are observed in K-, Na-, and Li-doped ZnO with the values 3.150, 3.144, and 3.142 eV. Due to better crystalline quality, ZnO:K shows a lower emissivity than others. The emissivity of K-doped ZnO decreases to the minimum value(0.804), at 1200 °C and holding 2 h. Compared with KNO3 as K source, K2CO3 doped ZnO has lower emissivities.
文摘With rutin standard sample as the comparison, flavonoid extraction rate as an indicator, UV-2450 ultraviolet visible light spectrophotometer to measure flavonoid content in planted Trollius chinensis through orthogonal experiment, this experiment optimizes process condition of flavonoid in Trollius chinensis through water extraction and ethanol extraction. The result shows that flavonoid extraction rate of Trollius chinensis through ethanol extraction method is obviously higher than water extraction, and the optimal extraction process condition is： ethanol concentration is 75%, extraction time is 90min, extraction times are 3, and fluid material ratio is 20：1.
基金Project(2005CB623701) supported by the National Key Basic Research Program of China
文摘TiO2/bauxite-tailings （TiO2/BTs） composites were prepared via a chemical liquid deposition method and characterized by X-ray diffractometry （XRD）, scanning electronic microscopy （SEM） and N2 adsorption analysis. The photocatalytic performance of TiO2/BTs composites was evaluated with UV-Vis spectrophotometer following the changes of phenol concentration under different illumination time. Effects of the calcination temperature, the pH and the cycles on the photocatalytic activity of TiO2/BTs composites were investigated. The composites calcined at 500 and 600 ℃ exhibit the best photocatalytic performance, and the phenol degradation ratios reacting for 40 and 160 rain reach 35% and 78% respectively under the same conditions, higher than those of 29% and 76% of the Degussa P25（TiO2）. The ability of TiO2/BTs500 （BTs500 represents bauxite-tailings calcined at 500 ℃） composites to degrade phenol increases with decreasing pH.
文摘The mixed P3HT （poly（3-hexylthiophene）） and [6,6]-PCBM （phenyl C61-butyric acid methyl ester） organic thin films were investigated for electronic structure using UV-Vis spectrophotometer and PESA （photo-electron spectroscopy in air）. Furthermore, ESR （electron spin resonance） and AFM （atomic force microscopy） were used to investigate the surface morphology and molecular orientation, respectively. ESR analysis indicated the molecular orientation of the P3HT crystalline in the blend thin films, which the crystalline oriented normal to the substrate with distribution of 35°. AFM images indicated that the surface morphology of P3HT film was affected by the presence of PCBM nanoparticles. Solution-processed OTFTs （organic thin-film transistors） based on P3HT/PCBM blend thin film in a top source-drain contact structure was fabricated, and the electrical characteristics of the devices were also investigated. A unipolar property with p-channel characteristics were obtained in glove box measurement.
基金Acknowledgments： This work was funded by the New Century Talent Support Program （No. NCET-04-0746） and the Region Technology Development Program of Chinese Ministry of Education （No. 02095）, and the Natural Science Foundation of Hubei province （No. 2002AB094）, the Youth Talent Foundation of Hubei province （No. 2003AB014） and the Educational Office Key Research Program of Hubei Province of China （No. Z200627002）.
文摘The enzyme activities of phenylalanine ammonia-lyase from six years old Ginkgo biloba leaves in the potted orchard were induced by four groups of metal ions respectively. The PAL activities and flavonoids content were measured by the UV-Vis spectrophotometer. Changes of the whole year were also studied. The results showed that four groups of metal ion treatments had significant effects on the PAL activities and flavonoids contents in Ginkgo leaves. The treatments with 0.1% and 0.3% FeSO4, 0.1%, 0.2% and 0.3% ZnSO4, 0.1%, 0.3% and 0.5% MnSO4, 0.1% and 0.4% CuSO4 not only enhanced flavonoids contents, but also extended the optimum harvest dates of ginkgo leaves. The optimum combination was 0.1% FeSO4, 0.2% ZnSO4, 0.3% MnSO4, and 0.4% CuSO4. It could improve flavonoids content up to 1.619 4%.
基金Foundation items: National Natural Science Foundations of China (No.10835004,No.10775031)Science and Technology Commission of Shanghai Municipality,China (No. 10XD1400100)
文摘The hydrophobic films of TixOy-CmHn. deposited from mixture gases of titanium isopropoxide （TTIP） and oxygen by plasma enhanced chemical vapor deposition （PECVD） were investigated. The films were investigated by scanning electron microscope （ SEM ）, transmission electron microscope （ TEM ）, Fourier transform infrared spectrometer （ FTIR）, X-Ray diffraction （ XRD ）, element analysis （ EA ）, ultraviolet visible spectrometer （ UV-Vis）, and water contact angle （WCA）. The results reveal that the surface of the films is formed by mierosized papillaes aggregated by inorganic and organic phases of complex nanoparticles with size from 50 nm to 200 nm when the discharge power is increased from 40 W to 150 W. All fdms demonstrate the strong broad of Ti-O-Ti stretching vibration at 400 -800cm-1, -CH bending vibration at 1 388 cm -1, and broadening -OH stretching vibration at 3 000-3500 cm-1 With the increase of the discharge power, the asdeposited film changes from amorphous to crystallization. The WCA of the film can be as high as 160°, indicating the hydrophobicity. The films show a similar ultraviolet absorption property as the bulk TiO2 film. The composition of the composition of film deposited at 150 W can be formulated as Tio.302-C1.5H3. Therefore, the composition formula of this hydrophobic film could be expressed as TiO2-C5H10O4.7. It is believed that the complex micro/nano structures of TiO2 and C5H10O4.7 residues are responsible for the observed hydrophobicity and the ultraviolet absorption property of the film.
基金supported by the National Natural Science Foundation of China(Nos.61274113,61404091,61505144,51502203 and 51502204)the Opening Fund of Key Laboratory of Silicon Device Technology in Chinese Academy of Sciencesthe Tianjin Natural Science Foundation(Nos.14JCZDJC31500 and 14JCQNJC00800)
文摘Gallium oxide （Ga203） films were deposited on singlecrystalline sapphire （0001） substrate by radio frequency （RF） magnetron sputtering technique in the temperature range of 300--500 ℃. The microstructure of the fl-Ga203 films were investigated in detail using X-ray diffractometer （XRD） and scanning electron microscope （SEM）. The results show that the film prepared at 500℃ exhibits the best crystallinity with a monoclinic structure （fl-Ga203）. Structure analysis reveals a clear out-of-plane orientation offl-Ga203 （201） II A1203 （0001）. The average transmittance of these films in the visible wavelength range exceeds 90%, and the optical band gap of the films varies from 4.68 eV to 4.94 eV which were measured by an ultraviolet-visible-near infrared （UV-vis-NIR） spectrophotometer. Therefore, it is hopeful that the fl-Ga203 film can be used in the UV optoelectronic devices.
基金supported by the National Natural Science Foundation of China(Nos.11504435 and 11504436)the Natural Science Foundation of Hubei(Nos.2013CFA0522014CFA051 and 2015CFB364)
文摘Nano transparent conducting titanium-zinc oxide(Ti-Zn O) thin films were prepared on glass substrates by radio frequency(RF) magnetron sputtering technique. The deposited films are characterized by X-ray diffraction(XRD), four-probe meter and UV-visible spectrophotometer. The effects of Ti-doping content on the structural, optical and electrical properties of the films are investigated. The XRD results show that the obtained films are polycrystalline with a hexagonal wurtzite structure and preferentially oriented in the(002) crystallographic direction. The structural and optoelectronic characteristics of the deposited films are subjected to the Ti-doping content. The Ti-Zn O sample fabricated with the Ti-doping content of 3%(weight percentage) possesses the best crystallinity and optoelectronic performance, with the highest degree of preferred(002) orientation of 99.87%, the largest crystallite size of 83.2 nm, the minimum lattice strain of 6.263×10^(-4), the highest average visible transmittance of 88.8%, the lowest resistivity of 1.18×10^(-3) Ω·cm and the maximum figure of merit(FOM) of 7.08×10~3 Ω^(-1)·cm^(-1). Furthermore, the optical bandgaps of the films are evaluated by extrapolation method and observed to be an increasing tendency with the increase of the Ti-doping content.
基金supported by the Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials
文摘The Cu2 Zn Sn S4(CZTS) powders are successfully synthesized by using Zn S and Cu2 Sn S3 as raw materials directly without any intermediate phase at 450 °C for 3 h in Ar atmosphere.The crystalline structure,morphology and optical properties of the CZTS powders are characterized by X-ray diffraction(XRD),Raman spectrum,field emission scanning electron microscopy(FESEM) and ultraviolet-visible(UV-vis) spectrophotometer,respectively.The results show that the band gap of the obtained CZTS is 1.53 e V.The CZTS film is fabricated by spin coating a mixture of CZTS powders and novolac resin with a weight percentage of 30%.The photoelectrical properties of such CZTS films are measured,and the results show an incident light density of 100 m W·cm-2 with the bias voltage of 0.40 V,and the photocurrent density can approach 9.80×10-5 A·cm2 within 50 s,giving an on/off switching ratio of 1.64.
