石棒绣线菊(Spiraea media Schmidt)为蒿薇科绣钱菊亚科绣线菊属植物,主要分布于我国东北、华北、西北、苏联、中亚和东南欧等地的多石山区。国内外文献中仅记载其叶片中含大量维生素C(约311.1~164.3mg%),可治疗胃肠道、妇科疾病,对其...石棒绣线菊(Spiraea media Schmidt)为蒿薇科绣钱菊亚科绣线菊属植物,主要分布于我国东北、华北、西北、苏联、中亚和东南欧等地的多石山区。国内外文献中仅记载其叶片中含大量维生素C(约311.1~164.3mg%),可治疗胃肠道、妇科疾病,对其药理作用及化学成分无详细研究报道,我省东部山区居民常采摘其叶代茶饮用。据了解,该区不仅人均寿龄高,且极少流行疾病及发生地方病。为此,我们将石棒绣线菊对家鸽动脉粥样硬化形成及动物血清胆固醇含量的影响进行了研究。动物:家鸽、鹌鹑、大鼠、乳幼大鼠、小鼠。药物及仪器:石棒绣线菊(100%水煎剂)、泽泻(500%醇提物);722光栅分光光度仪。展开更多
The Eu3+-doped La2Zr207 phosphor with rod-like morphology was successfully synthesized by conventional solid state reaction and hydrothermal method. X-ray diffraction patterns, transmission electron microscopy, and p...The Eu3+-doped La2Zr207 phosphor with rod-like morphology was successfully synthesized by conventional solid state reaction and hydrothermal method. X-ray diffraction patterns, transmission electron microscopy, and photoluminescence spectra were employed to charac- terize its structure and morphology as well as luminescent properties. The results indicated that the red-emitting phosphor La2Zr207:Eu3+ had well crystallized and belonged to the cubic structure with space group of Fd3m. The as-obtained product mainly appeared as straight nanorods with an average diameter of 47 nm and length of 50-700 nm. The pos- sible growth mechanism was also discussed. It was found that under blue excitation with a wavelength of 466 nm, the La2Zr2OT:Eu3+ phosphor exhibited a characteristic red emission at 616 nm that was attributed to the hypersensitive 5D0--*TF2 electric dipole transition of Eu3+ ions. Meanwhile, it was more interesting to note that the emission of 5D1--*TFj (J=0, 1, 2) transitions and the splitting patterns of 5D0---+TFJ (J--l, 2, 4) transitions of Eu3+ ions can be observed in the luminescent spectra of La2Zr207:Eu3+. It was demonstrated that Eu3+ preferred to occupy a low symmetry site.展开更多
We demonstrate the synthesis of C-Cl-codoped titania/attapulgite(TiO2/ATT) composites containing a mixture of TiO2 phases by a facile sol-gel method at 70 ℃ using titanium tetraisopropoxide as the TiO2 precursor an...We demonstrate the synthesis of C-Cl-codoped titania/attapulgite(TiO2/ATT) composites containing a mixture of TiO2 phases by a facile sol-gel method at 70 ℃ using titanium tetraisopropoxide as the TiO2 precursor and ATT as a support for the TiO2 nanoparticles.The photocatalytic activity of the C-Cl-codoped TiO2/ATT composites with mixed anatase/brookite/rutile phases obtained at pH= 3.0 was much higher than that of commercially available Degussa P25 for the photocatalytic degradation of acid red G under visible-light irradiation.The excellent photocatalytic activity of the developed composite originates from the nonmetal codoping,which extends the absorption edge of TiO2 into visible region,and the presence of multiple phases,which slow the recombination of photoexcited electron/hole pairs.The formation of hydroxyl radicals during the photocatalytic degradation process was detected by photoluminescence probing using terephthalic acid.A mechanism for photocatalysis over the C-Cl-codoped TiO2/ATT composites was proposed.展开更多
The natural attapulgite(NAPT)was disaggregated by high-pressure homogenization technology combined with extrusion process to prepare the attapulgite with disaggregated rod crystal bundles(DAPT)and large specific surfa...The natural attapulgite(NAPT)was disaggregated by high-pressure homogenization technology combined with extrusion process to prepare the attapulgite with disaggregated rod crystal bundles(DAPT)and large specific surface area of 133.7 m^(2)/g.NAPT and DAPT were incorporated into the silicone rubber to obtain the composite NAPTSR and DAPT-SR by mechanical blending method,respectively.After thermal oxidative ageing at 300℃ for 0.5 h,temperature for the 5%weight loss increased greatly from 385℃ of the neat silicone rubber to 396-399℃ with addition of NAPT and DAPT.NAPT and DAPT enhanced the interaction between the filler nanoparticles and rubber matrix thus inhibited the nanoparticle agglomeration.The conservation rate of the side methyl group in NAPT-SR and DAPT-SR was greatly improved after ageing.Therefore,the thermal oxidative degradation and ageing performance of the silicone rubber composites was significantly reinforced.Moreover,DAPT could greatly restrain the growth of nanoparticles after ageing.Therefore,DAPT-SR showed the better retention of tensile strength(40.6%),elongation at break(34.9%)and tear strength(30.1%)compared with the corresponding mechanical properties of the neat silicone rubber(10.6%,7.4%,and 5.0%)after ageing.展开更多
Attapulgite clay is a kind of special silicate mineral with high adsorption capacity thanks to its loose structure and porous surface. In this paper, the attapulgite clay was treated effectively with acid under microw...Attapulgite clay is a kind of special silicate mineral with high adsorption capacity thanks to its loose structure and porous surface. In this paper, the attapulgite clay was treated effectively with acid under microwave thermal activation and ultrasonic vibration, respectively, and characterized by XRD, N2 adsorption, FT-IR and SEM. The desulfurization performance of the modified attapulgite clay was then evaluated by using simulated gasoline as the feed. The test results showed that the thiophene removal rate increased with an increasing dosage of hydrochloric acid during microwave modification of attapulgite clay. When the concentration of hydrochloric acid reached 15%, the increase of desulfurization rate became slower, and the desulfurization rate was about 69%.展开更多
[Objective] The paper was to study the dynamic adsorption of microwave modified attapulgite on micro-polluted phenol wastewater. [Method] Cetyl trimethyl ammonium bromide (CATB) modified attapulgite was used to modi...[Objective] The paper was to study the dynamic adsorption of microwave modified attapulgite on micro-polluted phenol wastewater. [Method] Cetyl trimethyl ammonium bromide (CATB) modified attapulgite was used to modify attapulgite, and conducted dynamic test on micro-polluted phenol wastewater. The dynamic charac- teristics of phenol removal were also studied. [Result] Attapulgite modified by CATB has strong adsorption ability on phenol in micro-polluted water, the phenol removal rate increased with the decrease of flow rate of wastewater. When pH value was 6- 8, phenol concentration in wastewater was 17.74 mg/L, flow rate was 2 m/s and ad- sorption time was 25 rain, the removal rate reached 93.07%. The modified atta- pulgite could be regenerated with alkali, and its adsorption ability after regeneration had no obvious decline. The dynamic adsorption process of phenol accorded with the first-order kinetic equation. [Conclusion] The study provided basis for further study on "organic matter removal in wastewater.展开更多
Low optical absorption and photocorrosion are two crucial issues limiting the practical applications of zinc oxide(ZnO)-based photocatalysts.In this paper,we report the fabrication of graphitic-carbon-mediated ZnO nan...Low optical absorption and photocorrosion are two crucial issues limiting the practical applications of zinc oxide(ZnO)-based photocatalysts.In this paper,we report the fabrication of graphitic-carbon-mediated ZnO nanorod arrays(NRAs)with enhanced photocatalytic activity and photostability for CO2 reduction under visible light irradiation.ZnO NRA/C-x(x=005,01,02,and 03)nanohybrids are prepared by calcining pre-synthesized ZnO NRAs with different amounts of glucose(0.05,0.1,0.2,and 0.3 g)as a carbon source via a hydrothermal method.X-ray photoelectron spectroscopy reveals that the obtained ZnO NRA/C-x nanohybrids are imparted with the effects of both carbon doping and carbon coating,as evidenced by the detected C-O-Zn bond and the C-C,C-O and C=O bonds,respectively.While the basic structure of ZnO remains unchanged,the UV-Vis absorption spectra show increased absorbance owing to the carbon doping effect in the ZnO NRA/C-x nanohybrids.The photoluminescence(PL)intensities of ZnO NRA/C-x nanohybrids are lower than that of bare ZnO NRA,indicating that the graphitic carbon layer coated on the surface of the ZnO NRA significantly enhances the charge carrier separation and transport,which in turn enhances the photoelectrochemical property and photocatalytic activity of the ZnO NRA/C-x nanohybrids for CO2 reduction.More importantly,a long-term reaction of photocatalytic CO2 reduction demonstrates that the photostability of ZnO NRA/C-x nanohybrids is significantly increased in comparison with the bare ZnO NRA.展开更多
A convenient and scalable technique for the synthesis of rutile titanium dioxide(TiO2) nano-rods was presented by using bulk TiO2 powder, sodium hydroxide(NaOH) and distilled water as raw materials. X-ray diffraction(...A convenient and scalable technique for the synthesis of rutile titanium dioxide(TiO2) nano-rods was presented by using bulk TiO2 powder, sodium hydroxide(NaOH) and distilled water as raw materials. X-ray diffraction(XRD) and field emission scanning electron microscopy(FESEM) studies indicate that the prepared sample is crystalline and free from any impurities, however, it has no distinct shape and possesses a huge degree of agglomeration, and the average crystal size is around 40 nm. After annealing the sample at 600 °C for 2 h, it is observed through FESEM that nano-rods are formed. And XRD analysis shows that the nano-rods are single crystalline with distinct and smooth surfaces in different sizes with average length of about 1 μm and diameter of about 80 nm. Further UV-visible spectroscopy and Raman studies were conducted for the prepared sample and the band gap of the final product is found to be 3.40 eV.展开更多
The aim of this research was to develop effective alternative therapies to reduce antibiotic use in animal agriculture. In this study, the efficacy of copper-modified palygorskite(CM-Pal) in preventing diarrhea caus...The aim of this research was to develop effective alternative therapies to reduce antibiotic use in animal agriculture. In this study, the efficacy of copper-modified palygorskite(CM-Pal) in preventing diarrhea caused by Salmonella was specifically examined both in vitro and in vivo. The CM-Pal was prepared with palygorskite(Pal) and copper nitrate. The antibacterial activity of the CM-Pal was detected by comparing the differences in cell numbers on plate count agar before and after adding the CM-Pal to Salmonella typhimurium cultures. Seventy ICR mice were then allocated into seven groups. Five groups(the treatment groups) were infected with S. typhimurium by intraperitoneal(i.p.) injection and were given Pal, CM-Pal, montmorillonite powder, gentamicin, and physiological saline, respectively. One group(the prevention group) was given CM-Pal before infection with S. typhimurium. Another group(the uninfected group) was not infected with S. typhimurium. The effects of Pal, CM-Pal, montmorillonite powder, and gentamicin on the treatment or prevention of diarrhea in the mice were examined by stool studies, fecal scoring, and assessment of growth performance and villus height. The CM-Pal had satisfactory anti-bacterial properties in vitro: the antibacterial rate was 100% after 2 h incubation with S. typhimurium NJS1 cultures(1×10-6 colony-forming units(CFU)/ml). In the in vivo experiment, the CM-Pal exerted superior effects in the treatment and prevention of diarrhea in mice compared with Pal, montmorillonite powder, and gentamicin. In the CM-Pal group, no mice showed signs of diarrhea at 24 h post infection(p.i.), and all mice fully recovered from infection. However, the Pal group, montmorillonite group, and gentamicin group only recovered after 48, 48, and 96 h, respectively. The villus height level in the CM-Pal treatment group recovered at 3 d p.i. However, the recovery time of the other groups was longer(at least 5 d). The CM-Pal prevention group had a better effect on weight gain than the other groups. This study suggested that CM-Pal may be an effective alternative to conventional antibiotics for the treatment and prevention of animal diarrhea caused by Salmonella.展开更多
The surface properties of intrinsic and activated attapulgite were studied using potentiometric titration. The sorption mechanisms of Th(IV) on intrinsic and activated attapulgite were investigated by employing surf...The surface properties of intrinsic and activated attapulgite were studied using potentiometric titration. The sorption mechanisms of Th(IV) on intrinsic and activated attapulgite were investigated by employing surface complexation model and FITEQL 3.2 code. The results indicated that the sorption sites of intrinsic attapulgite involved in the sorption process were main ion exchange site ( ≡ XNa/K), strong site (≡ SsOH) and weak site ( ≡ SwOH), while only strong site ( ≡SSOH) and weak site (≡SwOH) were predominant for activated attapulgite. At pH 〈 2.5, the species of Th(IV) was main Th4+ in aqueous solution; then the hydrolysis species of Th(IV) (i.e., Th(OH)22+, Th(OH)3+ and Yh(OH)40) gradually formed as pH increasing. For the sorption of Th(IV) on intrinsic attapulgite, both ion exchange species ( ≡ X2Th) and inner-sphere surface complexes ( ≡ SsOTh) were dominant, while only inner-sphere surface complexes (i.e., ≡SSOThOH and ≡ SWOTh) were observed for Th(IV) sorption to activated attapulgite. In the presence of humic acid (HA), the sorption of Th(IV) on activated attapulgite was obviously enhanced; and both ≡ SsOH-HA-Th and≡ SSOTh were the predominant speciation. It was also interesting to find that the addition of HA obviously provoked the desorption behavior of Th(IV).展开更多
A promising strategy for the selective growth of ZnO nanorods on SiO2/Si substrates using a graphene buffer layer in a low temperature solution process is described. High densities of ZnO nanorods were grown over a la...A promising strategy for the selective growth of ZnO nanorods on SiO2/Si substrates using a graphene buffer layer in a low temperature solution process is described. High densities of ZnO nanorods were grown over a large area and most ZnO nanorods were vertically well-aligned on graphene. Furthermore, selective growth of ZnO nanorods on graphene was realized by applying a simple mechanical treatment, since ZnO nanorods formed on graphene are mechanically stable on an atomic level. These results were confirmed by first principles calculations which showed that the ZnO-graphene binding has a low destabilization energy. In addition, it was found that ZnO nanorods grown on SiO2/Si with a graphene buffer layer have better optical properties than ZnO nanorods grown on bare SiO2/Si. The nanostructured ZnO-graphene materials have promising applications in future flexible electronic and optical devices.展开更多
文摘石棒绣线菊(Spiraea media Schmidt)为蒿薇科绣钱菊亚科绣线菊属植物,主要分布于我国东北、华北、西北、苏联、中亚和东南欧等地的多石山区。国内外文献中仅记载其叶片中含大量维生素C(约311.1~164.3mg%),可治疗胃肠道、妇科疾病,对其药理作用及化学成分无详细研究报道,我省东部山区居民常采摘其叶代茶饮用。据了解,该区不仅人均寿龄高,且极少流行疾病及发生地方病。为此,我们将石棒绣线菊对家鸽动脉粥样硬化形成及动物血清胆固醇含量的影响进行了研究。动物:家鸽、鹌鹑、大鼠、乳幼大鼠、小鼠。药物及仪器:石棒绣线菊(100%水煎剂)、泽泻(500%醇提物);722光栅分光光度仪。
文摘The Eu3+-doped La2Zr207 phosphor with rod-like morphology was successfully synthesized by conventional solid state reaction and hydrothermal method. X-ray diffraction patterns, transmission electron microscopy, and photoluminescence spectra were employed to charac- terize its structure and morphology as well as luminescent properties. The results indicated that the red-emitting phosphor La2Zr207:Eu3+ had well crystallized and belonged to the cubic structure with space group of Fd3m. The as-obtained product mainly appeared as straight nanorods with an average diameter of 47 nm and length of 50-700 nm. The pos- sible growth mechanism was also discussed. It was found that under blue excitation with a wavelength of 466 nm, the La2Zr2OT:Eu3+ phosphor exhibited a characteristic red emission at 616 nm that was attributed to the hypersensitive 5D0--*TF2 electric dipole transition of Eu3+ ions. Meanwhile, it was more interesting to note that the emission of 5D1--*TFj (J=0, 1, 2) transitions and the splitting patterns of 5D0---+TFJ (J--l, 2, 4) transitions of Eu3+ ions can be observed in the luminescent spectra of La2Zr207:Eu3+. It was demonstrated that Eu3+ preferred to occupy a low symmetry site.
基金supported by the National Basic Research Program of China (973 Program, 2007CB613302)the Natural Science Foundation of Hubei Province (2016CFA078)~~
文摘We demonstrate the synthesis of C-Cl-codoped titania/attapulgite(TiO2/ATT) composites containing a mixture of TiO2 phases by a facile sol-gel method at 70 ℃ using titanium tetraisopropoxide as the TiO2 precursor and ATT as a support for the TiO2 nanoparticles.The photocatalytic activity of the C-Cl-codoped TiO2/ATT composites with mixed anatase/brookite/rutile phases obtained at pH= 3.0 was much higher than that of commercially available Degussa P25 for the photocatalytic degradation of acid red G under visible-light irradiation.The excellent photocatalytic activity of the developed composite originates from the nonmetal codoping,which extends the absorption edge of TiO2 into visible region,and the presence of multiple phases,which slow the recombination of photoexcited electron/hole pairs.The formation of hydroxyl radicals during the photocatalytic degradation process was detected by photoluminescence probing using terephthalic acid.A mechanism for photocatalysis over the C-Cl-codoped TiO2/ATT composites was proposed.
基金supported by the Key Special Program on the S&T for the Pollution Control and Treatment of Water Bodies (No.2017ZX07603-003)。
文摘The natural attapulgite(NAPT)was disaggregated by high-pressure homogenization technology combined with extrusion process to prepare the attapulgite with disaggregated rod crystal bundles(DAPT)and large specific surface area of 133.7 m^(2)/g.NAPT and DAPT were incorporated into the silicone rubber to obtain the composite NAPTSR and DAPT-SR by mechanical blending method,respectively.After thermal oxidative ageing at 300℃ for 0.5 h,temperature for the 5%weight loss increased greatly from 385℃ of the neat silicone rubber to 396-399℃ with addition of NAPT and DAPT.NAPT and DAPT enhanced the interaction between the filler nanoparticles and rubber matrix thus inhibited the nanoparticle agglomeration.The conservation rate of the side methyl group in NAPT-SR and DAPT-SR was greatly improved after ageing.Therefore,the thermal oxidative degradation and ageing performance of the silicone rubber composites was significantly reinforced.Moreover,DAPT could greatly restrain the growth of nanoparticles after ageing.Therefore,DAPT-SR showed the better retention of tensile strength(40.6%),elongation at break(34.9%)and tear strength(30.1%)compared with the corresponding mechanical properties of the neat silicone rubber(10.6%,7.4%,and 5.0%)after ageing.
基金supported financially by the National Natural Science Foundation of China (21306162)the National 973 Project of China (2010CB226903)+1 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (14KJB430023)the Union Innovation Funds-Prospective Joint Research Project of Jiangsu Province (BY2012152)
文摘Attapulgite clay is a kind of special silicate mineral with high adsorption capacity thanks to its loose structure and porous surface. In this paper, the attapulgite clay was treated effectively with acid under microwave thermal activation and ultrasonic vibration, respectively, and characterized by XRD, N2 adsorption, FT-IR and SEM. The desulfurization performance of the modified attapulgite clay was then evaluated by using simulated gasoline as the feed. The test results showed that the thiophene removal rate increased with an increasing dosage of hydrochloric acid during microwave modification of attapulgite clay. When the concentration of hydrochloric acid reached 15%, the increase of desulfurization rate became slower, and the desulfurization rate was about 69%.
基金Supported by Innovation Fund Project of Ministry of Science and Technology(10C26213201183)~~
文摘[Objective] The paper was to study the dynamic adsorption of microwave modified attapulgite on micro-polluted phenol wastewater. [Method] Cetyl trimethyl ammonium bromide (CATB) modified attapulgite was used to modify attapulgite, and conducted dynamic test on micro-polluted phenol wastewater. The dynamic charac- teristics of phenol removal were also studied. [Result] Attapulgite modified by CATB has strong adsorption ability on phenol in micro-polluted water, the phenol removal rate increased with the decrease of flow rate of wastewater. When pH value was 6- 8, phenol concentration in wastewater was 17.74 mg/L, flow rate was 2 m/s and ad- sorption time was 25 rain, the removal rate reached 93.07%. The modified atta- pulgite could be regenerated with alkali, and its adsorption ability after regeneration had no obvious decline. The dynamic adsorption process of phenol accorded with the first-order kinetic equation. [Conclusion] The study provided basis for further study on "organic matter removal in wastewater.
文摘Low optical absorption and photocorrosion are two crucial issues limiting the practical applications of zinc oxide(ZnO)-based photocatalysts.In this paper,we report the fabrication of graphitic-carbon-mediated ZnO nanorod arrays(NRAs)with enhanced photocatalytic activity and photostability for CO2 reduction under visible light irradiation.ZnO NRA/C-x(x=005,01,02,and 03)nanohybrids are prepared by calcining pre-synthesized ZnO NRAs with different amounts of glucose(0.05,0.1,0.2,and 0.3 g)as a carbon source via a hydrothermal method.X-ray photoelectron spectroscopy reveals that the obtained ZnO NRA/C-x nanohybrids are imparted with the effects of both carbon doping and carbon coating,as evidenced by the detected C-O-Zn bond and the C-C,C-O and C=O bonds,respectively.While the basic structure of ZnO remains unchanged,the UV-Vis absorption spectra show increased absorbance owing to the carbon doping effect in the ZnO NRA/C-x nanohybrids.The photoluminescence(PL)intensities of ZnO NRA/C-x nanohybrids are lower than that of bare ZnO NRA,indicating that the graphitic carbon layer coated on the surface of the ZnO NRA significantly enhances the charge carrier separation and transport,which in turn enhances the photoelectrochemical property and photocatalytic activity of the ZnO NRA/C-x nanohybrids for CO2 reduction.More importantly,a long-term reaction of photocatalytic CO2 reduction demonstrates that the photostability of ZnO NRA/C-x nanohybrids is significantly increased in comparison with the bare ZnO NRA.
基金supported by the MKE (The Ministry of Knowledge Economy)Korea Under the ITRC (Information Technology Research Centre) support program supervised by the NIPA (National IT industry Promotion Agency) (NIPA-2012-H0301-12-2009)+1 种基金supported by the Ministry of Education, Science and Technology (MEST)National Research Foundation of Korea (NRF) through the Human Resource Training Project for Regional Innovation (2012H1B8A2026212)
文摘A convenient and scalable technique for the synthesis of rutile titanium dioxide(TiO2) nano-rods was presented by using bulk TiO2 powder, sodium hydroxide(NaOH) and distilled water as raw materials. X-ray diffraction(XRD) and field emission scanning electron microscopy(FESEM) studies indicate that the prepared sample is crystalline and free from any impurities, however, it has no distinct shape and possesses a huge degree of agglomeration, and the average crystal size is around 40 nm. After annealing the sample at 600 °C for 2 h, it is observed through FESEM that nano-rods are formed. And XRD analysis shows that the nano-rods are single crystalline with distinct and smooth surfaces in different sizes with average length of about 1 μm and diameter of about 80 nm. Further UV-visible spectroscopy and Raman studies were conducted for the prepared sample and the band gap of the final product is found to be 3.40 eV.
基金supported by the Foundation of Key Laboratory for Palygorskite Science and Applied Technology of Jiangsu Province(No.HPK201506)the Natural Science Foundation of Jiangsu Province(No.BK20130686)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),China
文摘The aim of this research was to develop effective alternative therapies to reduce antibiotic use in animal agriculture. In this study, the efficacy of copper-modified palygorskite(CM-Pal) in preventing diarrhea caused by Salmonella was specifically examined both in vitro and in vivo. The CM-Pal was prepared with palygorskite(Pal) and copper nitrate. The antibacterial activity of the CM-Pal was detected by comparing the differences in cell numbers on plate count agar before and after adding the CM-Pal to Salmonella typhimurium cultures. Seventy ICR mice were then allocated into seven groups. Five groups(the treatment groups) were infected with S. typhimurium by intraperitoneal(i.p.) injection and were given Pal, CM-Pal, montmorillonite powder, gentamicin, and physiological saline, respectively. One group(the prevention group) was given CM-Pal before infection with S. typhimurium. Another group(the uninfected group) was not infected with S. typhimurium. The effects of Pal, CM-Pal, montmorillonite powder, and gentamicin on the treatment or prevention of diarrhea in the mice were examined by stool studies, fecal scoring, and assessment of growth performance and villus height. The CM-Pal had satisfactory anti-bacterial properties in vitro: the antibacterial rate was 100% after 2 h incubation with S. typhimurium NJS1 cultures(1×10-6 colony-forming units(CFU)/ml). In the in vivo experiment, the CM-Pal exerted superior effects in the treatment and prevention of diarrhea in mice compared with Pal, montmorillonite powder, and gentamicin. In the CM-Pal group, no mice showed signs of diarrhea at 24 h post infection(p.i.), and all mice fully recovered from infection. However, the Pal group, montmorillonite group, and gentamicin group only recovered after 48, 48, and 96 h, respectively. The villus height level in the CM-Pal treatment group recovered at 3 d p.i. However, the recovery time of the other groups was longer(at least 5 d). The CM-Pal prevention group had a better effect on weight gain than the other groups. This study suggested that CM-Pal may be an effective alternative to conventional antibiotics for the treatment and prevention of animal diarrhea caused by Salmonella.
基金supported by the National Natural Science Foundation of China (20871062, J1030932)the Fundamental Research Funds for the Central Universities (lzujbky-2010-215)the National Synchrotron Radiation Innovation Foundation of Ministry of Education (20090137S)
文摘The surface properties of intrinsic and activated attapulgite were studied using potentiometric titration. The sorption mechanisms of Th(IV) on intrinsic and activated attapulgite were investigated by employing surface complexation model and FITEQL 3.2 code. The results indicated that the sorption sites of intrinsic attapulgite involved in the sorption process were main ion exchange site ( ≡ XNa/K), strong site (≡ SsOH) and weak site ( ≡ SwOH), while only strong site ( ≡SSOH) and weak site (≡SwOH) were predominant for activated attapulgite. At pH 〈 2.5, the species of Th(IV) was main Th4+ in aqueous solution; then the hydrolysis species of Th(IV) (i.e., Th(OH)22+, Th(OH)3+ and Yh(OH)40) gradually formed as pH increasing. For the sorption of Th(IV) on intrinsic attapulgite, both ion exchange species ( ≡ X2Th) and inner-sphere surface complexes ( ≡ SsOTh) were dominant, while only inner-sphere surface complexes (i.e., ≡SSOThOH and ≡ SWOTh) were observed for Th(IV) sorption to activated attapulgite. In the presence of humic acid (HA), the sorption of Th(IV) on activated attapulgite was obviously enhanced; and both ≡ SsOH-HA-Th and≡ SSOTh were the predominant speciation. It was also interesting to find that the addition of HA obviously provoked the desorption behavior of Th(IV).
文摘A promising strategy for the selective growth of ZnO nanorods on SiO2/Si substrates using a graphene buffer layer in a low temperature solution process is described. High densities of ZnO nanorods were grown over a large area and most ZnO nanorods were vertically well-aligned on graphene. Furthermore, selective growth of ZnO nanorods on graphene was realized by applying a simple mechanical treatment, since ZnO nanorods formed on graphene are mechanically stable on an atomic level. These results were confirmed by first principles calculations which showed that the ZnO-graphene binding has a low destabilization energy. In addition, it was found that ZnO nanorods grown on SiO2/Si with a graphene buffer layer have better optical properties than ZnO nanorods grown on bare SiO2/Si. The nanostructured ZnO-graphene materials have promising applications in future flexible electronic and optical devices.