As a natural aromatic polymer,lignin has great potential but limited industrial application due to its complex chemical structure.Among strategies for lignin conversion,biodegradation has attracted promising interest ...As a natural aromatic polymer,lignin has great potential but limited industrial application due to its complex chemical structure.Among strategies for lignin conversion,biodegradation has attracted promising interest recently in term of efficiency,selectivity and mild condition.In order to overcome the issues of poor stability and non-reusability of enzyme in the biodegradation of lignin,this work explored a protocol of immobilized laccase on magnetic nanoparticles(MNPs)with rough surfaces for enhanced lignin model compounds degradation.Scanning electron microscope with energy dispersive spectrometer(SEM-EDS),flourier transformation infrared spectroscopy(FTIR)and thermal gravimetric analysis(TGA)were utilized to characterize the immobilization of laccase.The results showed a maximum activity recovery of 64.7%towards laccase when it was incubated with MNPs and glutaraldehyde(GA)with concentrations of 6 mg·ml^-1and 7.5 mg·ml^-1for 5 h,respectively.The immobilized laccase showed improved thermal stability and pH tolerance compared with free laccase,and remained more than 80%of its initial activity after 20 days of storage at 4℃.In addition,about 40%residual activity of the laccase remained after 8 times cycles.Gas chromatography–mass spectrometry(GC–MS)was utilized to characterize the products of lignin model compound degradation and activation,and the efficiency of immobilized laccase was calculated to be 1–5 times that of free laccase.It was proposed that the synergistic effect between MNPs and laccase displays an important role in the enhancement of stability and activity in lignin model compound biodegradation.展开更多
Genetic algorithm and partial least square（GA-PLS）,kernel PLS（KPLS） and Levenberg-Marquardt artificial neural network（L-M ANN） techniques were used to investigate the correlation between retention time（RT） and...Genetic algorithm and partial least square（GA-PLS）,kernel PLS（KPLS） and Levenberg-Marquardt artificial neural network（L-M ANN） techniques were used to investigate the correlation between retention time（RT） and descriptors for 15 nanoparticle compounds obtained by the comprehensive two-dimensional gas chromatography system（GC × GC）.Application of the dodecanethiol monolayer-protected gold nanoparticle（MPN） column was for a high-speed separation as the second column of GC × GC.The L-M ANN model with the final optimum network architecture of [13-5-1] gave a significantly better performance than the other models.This is the first research on the quantitative structure-retention relationship（QSRR） of nanoparticle compounds using the GA-PLS,GA-KPLS and L-M ANN.展开更多
The lap joint of T2 copper plate and 1060 pure aluminum plate was made by using the plasma arc welding method with adding Fe_(2)O_(3)nanoparticles in different proportions.The research analysis found that the thicknes...The lap joint of T2 copper plate and 1060 pure aluminum plate was made by using the plasma arc welding method with adding Fe_(2)O_(3)nanoparticles in different proportions.The research analysis found that the thickness of the IMC(intermetallic compound)and eutect-ic region decreased after the addition of nanoparticles due to its inhibitory effect.When the proportion of Fe_(2)O_(3)nanoparticles is 3%,the in-terface intermetallic compound layer is the thinnest.However,after this ratio is continuously increased,the inhibition effect is weakened by the agglomeration of nanoparticles,and the thickness begins to increase significantly.The mechanical and electrical properties of the joint are mainly affected by the thickness of the IMC layer.Excessive nanoparticles are agglomerated into large particles with high resistivity.Therefore,the tensile strength and relative electrical conductivity of the joint are first increasing and then decreasing with the increase of nanoparticle ratio.When the proportion of nanoparticles is 3%,the tensile strength and electrical conductivity are maximum.展开更多
The study describes chemo-enzymatic synthesis of organic disulphide compounds. The reaction was initiated by hydrolysis of thiol acetates using hydrolytic enzyme lipase (PPL) immobilized on to magnetic nanoparticles a...The study describes chemo-enzymatic synthesis of organic disulphide compounds. The reaction was initiated by hydrolysis of thiol acetates using hydrolytic enzyme lipase (PPL) immobilized on to magnetic nanoparticles and subsequent formation of organic disulphide compounds. Lipase was immobilized on to the magnetic nanoparticles by co-precipitation method via epichlorohydrin chitosan cross-linking, under mild and eco-friendly conditions. The immobilized lipase enzyme exhibited broad range of substrate specificity in synthesizing disulphide compounds, which involves both intra and inter-molecular disulphide bond formation under anaerobic conditions. The disulphide compounds synthesized also show a promising antimicrobial activity.展开更多
In this work, we report the preparation of silver nanoparticles (AgNPs) and the nanodecoration of α-cyclodextrin inclusion compounds (α-CD IC) microcrystals that contain palmitic (PAc) and stearic acids (SAc) like g...In this work, we report the preparation of silver nanoparticles (AgNPs) and the nanodecoration of α-cyclodextrin inclusion compounds (α-CD IC) microcrystals that contain palmitic (PAc) and stearic acids (SAc) like guest molecules. These IC provide a suitable environment for nucleation, epitaxial growth and immobilization of AgNPs that were obtained by the magnetron sputtering technique. The use of α-CD IC substrates with a specific surface morphology in which the functional group of the guest molecule faces outward preferentially from a crystal plane, is an efficient method for the preparation of AgNPs with a low size dispersion, which is probably due to the high affinity between the functional group of the surfactant carboxylic acid guest with the metal nanoparticles.展开更多
Pt nanoparticles entrapped in ordered mesoporous CMK-3 carbons with p6mm symmetry were prepared using a facile impregnation method, and the resulting materials were characterized using X-ray diffraction spectroscopy, ...Pt nanoparticles entrapped in ordered mesoporous CMK-3 carbons with p6mm symmetry were prepared using a facile impregnation method, and the resulting materials were characterized using X-ray diffraction spectroscopy, N2 adsorption-desorption, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The Pt nanoparticles were highly dispersed in the CMK-3 with 43.7% dispersion. The Pt/CMK-3 catalyst was an effective catalyst for the liquid-phase hydrogenation of nitrobenzene and its derivatives under the experimental conditions studied here. The Pt/CMK-3 catalyst was more active than commercial Pt/C catalyst in most cases. A highest turnover frequency of 43.8 s-1 was measured when the Pt/CMK-3 catalyst was applied for the hydrogenation of 2-methyl-nitrobenzene in ethanol under optimal conditions. It is worthy of note that the Pt/CMK-3 catalyst could be recycled easily, and could be reused at least fourteen times without any loss in activity or selectivity for the hydrogenation of nitrobenzene in ethanol.展开更多
The detection and removal of volatile organic compounds(VOCs) are of great importance to reduce the risk of indoor air quality concerns. This study reports the rational synthesis of a dual-functional Janus nanostructu...The detection and removal of volatile organic compounds(VOCs) are of great importance to reduce the risk of indoor air quality concerns. This study reports the rational synthesis of a dual-functional Janus nanostructure and its feasibility for simultaneous detection and removal of VOCs.The Janus nanostructure was synthesized via an anisotropic growth method, composed of plasmonic nanoparticles,semiconductors, and metal organic frameworks(e.g.,Au@ZnO@ZIF-8). It exhibits excellent selective detection to formaldehyde(HCHO, as a representative VOC) at room temperature over a wide range of concentrations(from 0.25 to100 ppm), even in the presence of water and toluene molecules as interferences. In addition, HCHO was also found to be partially oxidized into non-toxic formic acid simultaneously with detection. The mechanism underlying this technology was unraveled by both experimental measurements and theoretical calculations: ZnO maintains the conductivity, while ZIF-8 improves the selective gas adsorption; the plasmonic effect of Au nanorods enhances the visible-light-driven photocatalysis of ZnO at room temperature.展开更多
Nanoparticles have properties that can be fine-tuned by their size as well as shape.Hence,there is significant current interest in preparing nano-materials of small size dispersity and to arrange them in close-packed ...Nanoparticles have properties that can be fine-tuned by their size as well as shape.Hence,there is significant current interest in preparing nano-materials of small size dispersity and to arrange them in close-packed aggregates.This letter describes a way of synthesising silver nanoparticles and their protection to aggregate by silica gel.The combination of catalytic quantities of immobilized silver nanoparticles with reductive ability of NaBH_4 efficiently reduces aromatic nitroarenes to the corresponding amines in aqueous medium.Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogen and carboxylic acid groups.The silver particles immobilized on silica gel are stable in the presence of oxygen for several months.展开更多
The synthesis of high purity intermetallic FeAI nanoparticles using the flow-levitation （FL） method was reported. Iron and aluminium droplets were levitated stably at about 2 230℃. The morphology, clystal structure...The synthesis of high purity intermetallic FeAI nanoparticles using the flow-levitation （FL） method was reported. Iron and aluminium droplets were levitated stably at about 2 230℃. The morphology, clystal structure and chemical composition of FeAI nanoparticles were investigated by transmission electron microscopy （TEM）, high-resolution TEM, X-ray diffraction and energy dispersive spectrometry. The results show that the average particle size of these nanoparticles is about 34.5 nm. Measurements of the d-spacing from X-ray diffraction and electron diffraction studies confirm that the intermetallic nanoparticles have the same crystal structure （B2） as the bulk FeA1. A thin oxidation coating is formed around the particles when being exposed to air. Based on the XPS measurements, the surface coating of the FeAI nanoparticles is composed of Fe2O3 and FeAl2O4. Besides, hysteresis curve reveals that saturation magnetization （Ms） of FeA1 is 1.66 A/m2, and the coercivity is about 1.214×10^3 A/re.展开更多
The synthesis of nano-sized ZnO-doped CeO2 of 20 nm in crystal size by a coprecipitation technique was investigated by different scanning calorimetries/thermalgravimetrics(DSC/TG), X-ray diffraction (XRD), transmissio...The synthesis of nano-sized ZnO-doped CeO2 of 20 nm in crystal size by a coprecipitation technique was investigated by different scanning calorimetries/thermalgravimetrics(DSC/TG), X-ray diffraction (XRD), transmission electron microscopy (TEM) and ultraviolet (UV) absorbance. Azeotropic distillation processing was performed to effectively eliminate the residual water inside the as-prepared precipitate. Doping of ZnO results in the formation of solid solution. The crystal size of the nanoparticles increases with the increase of the doped ZnO amount, the calcination temperature and time. Doped CeO2 nanoparticles show excellent visible-light property and ultraviolet-absorption activity. Doping of ZnO doesn’t not weaken the UV-shielding property of ceria.展开更多
Nanotechnology has shown significant promise in development of drugs and drug delivery systems that can overcome all limitations and address urgent needs to improve efficacy of diagnosis and therapy of various disease...Nanotechnology has shown significant promise in development of drugs and drug delivery systems that can overcome all limitations and address urgent needs to improve efficacy of diagnosis and therapy of various diseases including cancer. The functionalization with neem compounds as synthesis and capping agent had shown very high anticancer activities against Gastric cancer cells in vitro. The biochemical factors like albumin, glucose, and DNA concentrations were modulated along with Protease inhibitor and Catalase activates, the various cancer specific proteins like p53, GRD 70 - 78 kDa and other proteins of sizes 35 - 40 kDa corresponding to H+K+ATPase protein etc. The apoptic activity and antiproliferative activity were demonstrated with Gastric cancer cells in vitro.展开更多
The graphite encapsulated a-Fe particles were prepared by reduction of stage-2 and stage-3 FeCI3 graphite intercalation compounds （GICs） with metallic potassium, X-ray diffraction analysis （XRD）, energy dispersive...The graphite encapsulated a-Fe particles were prepared by reduction of stage-2 and stage-3 FeCI3 graphite intercalation compounds （GICs） with metallic potassium, X-ray diffraction analysis （XRD）, energy dispersive X-ray spectroscopy （EDS） investigation and transmission electron microscopy （TEM） observation show that the reduction products of stage-2 FeCl3-GICs contains more abundant a-Fe nanoparticles than those of stage-3. High-resolution TEM （HRTEM） observation reveals that the nanoparticle of a-Fe was polycrystals or twins, which was real or quasi two-dimension in shape, and whose space orientation was strictly controlled by the graphene. Based on the experiment results, a possible growth model of the graphite encapsulated ct-Fe was proposed.展开更多
Ultrafine full-vulcanized polybutadiene rubber（UFBR） with particle sizes of ca.50―100 nm were used for modifying mechanical and processing performances of polypropylene（PP） with PP-g-maleic anhydride（PP-g-MA） a...Ultrafine full-vulcanized polybutadiene rubber（UFBR） with particle sizes of ca.50―100 nm were used for modifying mechanical and processing performances of polypropylene（PP） with PP-g-maleic anhydride（PP-g-MA） as a compatibilizer for enhancing the interfacial adhesion between the two components.The morphology,dynamical rheology response and mechanical properties of the blends were characterized by means of SEM,rheometer and tensile test,respectively.The results show that the ternary PP/UFBR blends compatibilized with PP-g-MA possess rheological behaviors like highly branched PP,while no obvious strain hardening is observed in its control binary PP/UFBR blends,a low level of PP-g-MA in PP/UFBR blends can even endow the material with rheological characteristics of high melt strength materials like highly branched PP.The enhancement interfacial interaction between the UFBR particles and PP matrix accounting for the rheological behavior of compatibilized blends and effectiveness of PP-g-MA were proposed and proved.展开更多
The metabolic activity of the fruits continues even after harvest,which results in the loss of bioactive compounds,a decrease in the quality of the fruits,softening and browning,among other negative effects.The use of...The metabolic activity of the fruits continues even after harvest,which results in the loss of bioactive compounds,a decrease in the quality of the fruits,softening and browning,among other negative effects.The use of certain elements such as silicon can improve postharvest quality,since it is involved in the metabolic,physiological and structural activity of plants,moreover can increase the quality of the fruits.In addition,nanotechnology has had a positive impact on crop yield,nutritional value,fruit quality and can improve antioxidant activity.For these reasons,the use of beneficial elements such as silicon in the form of nanoparticles can be a viable option to improve the characteristics of the fruits.In the present study was evaluated the application of potassium silicate(125,250 and 500 mg L^(−1))and SiO_(2) nanoparticles(125,250 and 500 mg L^(−1))during the development of the crop.The results showed that the application of silicon(potassium silicate and silicon nanoparticles)increased the content of total soluble solids(up to 15.6%higher than control),titratable acidity(up to 38.8%higher than control),vitamin C(up to 78.2%higher than control),phenols(up to 22%higher than control),flavonoids(up to 64.6%higher than control),and antioxidant activity in lipophilic compounds(up to 56.2%higher than control).This study suggests that the use of silicon can be a good option to increase the content of bioactive compounds in cucumber fruits when they are applied during the development of the crop.展开更多
基金supported by the Startup Foundation of Beijing Institute of Technology,China(3160011181808)。
文摘As a natural aromatic polymer,lignin has great potential but limited industrial application due to its complex chemical structure.Among strategies for lignin conversion,biodegradation has attracted promising interest recently in term of efficiency,selectivity and mild condition.In order to overcome the issues of poor stability and non-reusability of enzyme in the biodegradation of lignin,this work explored a protocol of immobilized laccase on magnetic nanoparticles(MNPs)with rough surfaces for enhanced lignin model compounds degradation.Scanning electron microscope with energy dispersive spectrometer(SEM-EDS),flourier transformation infrared spectroscopy(FTIR)and thermal gravimetric analysis(TGA)were utilized to characterize the immobilization of laccase.The results showed a maximum activity recovery of 64.7%towards laccase when it was incubated with MNPs and glutaraldehyde(GA)with concentrations of 6 mg·ml^-1and 7.5 mg·ml^-1for 5 h,respectively.The immobilized laccase showed improved thermal stability and pH tolerance compared with free laccase,and remained more than 80%of its initial activity after 20 days of storage at 4℃.In addition,about 40%residual activity of the laccase remained after 8 times cycles.Gas chromatography–mass spectrometry(GC–MS)was utilized to characterize the products of lignin model compound degradation and activation,and the efficiency of immobilized laccase was calculated to be 1–5 times that of free laccase.It was proposed that the synergistic effect between MNPs and laccase displays an important role in the enhancement of stability and activity in lignin model compound biodegradation.
文摘Genetic algorithm and partial least square（GA-PLS）,kernel PLS（KPLS） and Levenberg-Marquardt artificial neural network（L-M ANN） techniques were used to investigate the correlation between retention time（RT） and descriptors for 15 nanoparticle compounds obtained by the comprehensive two-dimensional gas chromatography system（GC × GC）.Application of the dodecanethiol monolayer-protected gold nanoparticle（MPN） column was for a high-speed separation as the second column of GC × GC.The L-M ANN model with the final optimum network architecture of [13-5-1] gave a significantly better performance than the other models.This is the first research on the quantitative structure-retention relationship（QSRR） of nanoparticle compounds using the GA-PLS,GA-KPLS and L-M ANN.
基金This work was supported by the National Natural Science Foundation of China(No.52165045).
文摘The lap joint of T2 copper plate and 1060 pure aluminum plate was made by using the plasma arc welding method with adding Fe_(2)O_(3)nanoparticles in different proportions.The research analysis found that the thickness of the IMC(intermetallic compound)and eutect-ic region decreased after the addition of nanoparticles due to its inhibitory effect.When the proportion of Fe_(2)O_(3)nanoparticles is 3%,the in-terface intermetallic compound layer is the thinnest.However,after this ratio is continuously increased,the inhibition effect is weakened by the agglomeration of nanoparticles,and the thickness begins to increase significantly.The mechanical and electrical properties of the joint are mainly affected by the thickness of the IMC layer.Excessive nanoparticles are agglomerated into large particles with high resistivity.Therefore,the tensile strength and relative electrical conductivity of the joint are first increasing and then decreasing with the increase of nanoparticle ratio.When the proportion of nanoparticles is 3%,the tensile strength and electrical conductivity are maximum.
文摘The study describes chemo-enzymatic synthesis of organic disulphide compounds. The reaction was initiated by hydrolysis of thiol acetates using hydrolytic enzyme lipase (PPL) immobilized on to magnetic nanoparticles and subsequent formation of organic disulphide compounds. Lipase was immobilized on to the magnetic nanoparticles by co-precipitation method via epichlorohydrin chitosan cross-linking, under mild and eco-friendly conditions. The immobilized lipase enzyme exhibited broad range of substrate specificity in synthesizing disulphide compounds, which involves both intra and inter-molecular disulphide bond formation under anaerobic conditions. The disulphide compounds synthesized also show a promising antimicrobial activity.
文摘In this work, we report the preparation of silver nanoparticles (AgNPs) and the nanodecoration of α-cyclodextrin inclusion compounds (α-CD IC) microcrystals that contain palmitic (PAc) and stearic acids (SAc) like guest molecules. These IC provide a suitable environment for nucleation, epitaxial growth and immobilization of AgNPs that were obtained by the magnetron sputtering technique. The use of α-CD IC substrates with a specific surface morphology in which the functional group of the guest molecule faces outward preferentially from a crystal plane, is an efficient method for the preparation of AgNPs with a low size dispersion, which is probably due to the high affinity between the functional group of the surfactant carboxylic acid guest with the metal nanoparticles.
基金supported by the National Natural Science Foundation of China(21273076 and 21373089)the Open Research Fund of Top Key Discipline of Chemistry in Zhejiang Provincial Colleges and Key Laboratory of the Ministry of Education for Catalysis Materials(Zhejiang Normal University,ZJHX2013)Shanghai Leading Academic Discipline Project (B409)~~
文摘Pt nanoparticles entrapped in ordered mesoporous CMK-3 carbons with p6mm symmetry were prepared using a facile impregnation method, and the resulting materials were characterized using X-ray diffraction spectroscopy, N2 adsorption-desorption, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The Pt nanoparticles were highly dispersed in the CMK-3 with 43.7% dispersion. The Pt/CMK-3 catalyst was an effective catalyst for the liquid-phase hydrogenation of nitrobenzene and its derivatives under the experimental conditions studied here. The Pt/CMK-3 catalyst was more active than commercial Pt/C catalyst in most cases. A highest turnover frequency of 43.8 s-1 was measured when the Pt/CMK-3 catalyst was applied for the hydrogenation of 2-methyl-nitrobenzene in ethanol under optimal conditions. It is worthy of note that the Pt/CMK-3 catalyst could be recycled easily, and could be reused at least fourteen times without any loss in activity or selectivity for the hydrogenation of nitrobenzene in ethanol.
基金the supports from the American Chemical Society Petroleum Research Fund(57072-DNI10)the National Science Foundation(CMMI-1727553)+2 种基金Partial support from the Virginia Commonwealth University Presidential Research Quest Fundsupports by the US Department of Energy under Awards No.DE-FG02-96ER45579and No.DE-AC02-05CH11231BET measurements(NSF I/UCR Center Grant,IIP 1464595)
文摘The detection and removal of volatile organic compounds(VOCs) are of great importance to reduce the risk of indoor air quality concerns. This study reports the rational synthesis of a dual-functional Janus nanostructure and its feasibility for simultaneous detection and removal of VOCs.The Janus nanostructure was synthesized via an anisotropic growth method, composed of plasmonic nanoparticles,semiconductors, and metal organic frameworks(e.g.,Au@ZnO@ZIF-8). It exhibits excellent selective detection to formaldehyde(HCHO, as a representative VOC) at room temperature over a wide range of concentrations(from 0.25 to100 ppm), even in the presence of water and toluene molecules as interferences. In addition, HCHO was also found to be partially oxidized into non-toxic formic acid simultaneously with detection. The mechanism underlying this technology was unraveled by both experimental measurements and theoretical calculations: ZnO maintains the conductivity, while ZIF-8 improves the selective gas adsorption; the plasmonic effect of Au nanorods enhances the visible-light-driven photocatalysis of ZnO at room temperature.
基金supports for this work by Shahid Chamran University Research Council
文摘Nanoparticles have properties that can be fine-tuned by their size as well as shape.Hence,there is significant current interest in preparing nano-materials of small size dispersity and to arrange them in close-packed aggregates.This letter describes a way of synthesising silver nanoparticles and their protection to aggregate by silica gel.The combination of catalytic quantities of immobilized silver nanoparticles with reductive ability of NaBH_4 efficiently reduces aromatic nitroarenes to the corresponding amines in aqueous medium.Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogen and carboxylic acid groups.The silver particles immobilized on silica gel are stable in the presence of oxygen for several months.
基金Project(10804101) supported by the National Natural Science Foundation of China
文摘The synthesis of high purity intermetallic FeAI nanoparticles using the flow-levitation （FL） method was reported. Iron and aluminium droplets were levitated stably at about 2 230℃. The morphology, clystal structure and chemical composition of FeAI nanoparticles were investigated by transmission electron microscopy （TEM）, high-resolution TEM, X-ray diffraction and energy dispersive spectrometry. The results show that the average particle size of these nanoparticles is about 34.5 nm. Measurements of the d-spacing from X-ray diffraction and electron diffraction studies confirm that the intermetallic nanoparticles have the same crystal structure （B2） as the bulk FeA1. A thin oxidation coating is formed around the particles when being exposed to air. Based on the XPS measurements, the surface coating of the FeAI nanoparticles is composed of Fe2O3 and FeAl2O4. Besides, hysteresis curve reveals that saturation magnetization （Ms） of FeA1 is 1.66 A/m2, and the coercivity is about 1.214×10^3 A/re.
基金Project (2005DFBA028) supported by the International Cooperation of Science and Technology Ministry of PRC Project (59925412) supported by the National Natural Science Foundation of China
文摘The synthesis of nano-sized ZnO-doped CeO2 of 20 nm in crystal size by a coprecipitation technique was investigated by different scanning calorimetries/thermalgravimetrics(DSC/TG), X-ray diffraction (XRD), transmission electron microscopy (TEM) and ultraviolet (UV) absorbance. Azeotropic distillation processing was performed to effectively eliminate the residual water inside the as-prepared precipitate. Doping of ZnO results in the formation of solid solution. The crystal size of the nanoparticles increases with the increase of the doped ZnO amount, the calcination temperature and time. Doped CeO2 nanoparticles show excellent visible-light property and ultraviolet-absorption activity. Doping of ZnO doesn’t not weaken the UV-shielding property of ceria.
文摘Nanotechnology has shown significant promise in development of drugs and drug delivery systems that can overcome all limitations and address urgent needs to improve efficacy of diagnosis and therapy of various diseases including cancer. The functionalization with neem compounds as synthesis and capping agent had shown very high anticancer activities against Gastric cancer cells in vitro. The biochemical factors like albumin, glucose, and DNA concentrations were modulated along with Protease inhibitor and Catalase activates, the various cancer specific proteins like p53, GRD 70 - 78 kDa and other proteins of sizes 35 - 40 kDa corresponding to H+K+ATPase protein etc. The apoptic activity and antiproliferative activity were demonstrated with Gastric cancer cells in vitro.
基金the Natural Science Foundation of Hubei Province (No.2004ABA090)the Fund from the Chengguang Plan of Wuhan(No.20065004116-35)
文摘The graphite encapsulated a-Fe particles were prepared by reduction of stage-2 and stage-3 FeCI3 graphite intercalation compounds （GICs） with metallic potassium, X-ray diffraction analysis （XRD）, energy dispersive X-ray spectroscopy （EDS） investigation and transmission electron microscopy （TEM） observation show that the reduction products of stage-2 FeCl3-GICs contains more abundant a-Fe nanoparticles than those of stage-3. High-resolution TEM （HRTEM） observation reveals that the nanoparticle of a-Fe was polycrystals or twins, which was real or quasi two-dimension in shape, and whose space orientation was strictly controlled by the graphene. Based on the experiment results, a possible growth model of the graphite encapsulated ct-Fe was proposed.
基金Supported by the National High Technology Research and Development Program of China(No.2002AA333040)the Special Funds of Science and Technology Bureau of Harbin for Hi-Tech Research,China(No.2007AA4BG140)
文摘Ultrafine full-vulcanized polybutadiene rubber（UFBR） with particle sizes of ca.50―100 nm were used for modifying mechanical and processing performances of polypropylene（PP） with PP-g-maleic anhydride（PP-g-MA） as a compatibilizer for enhancing the interfacial adhesion between the two components.The morphology,dynamical rheology response and mechanical properties of the blends were characterized by means of SEM,rheometer and tensile test,respectively.The results show that the ternary PP/UFBR blends compatibilized with PP-g-MA possess rheological behaviors like highly branched PP,while no obvious strain hardening is observed in its control binary PP/UFBR blends,a low level of PP-g-MA in PP/UFBR blends can even endow the material with rheological characteristics of high melt strength materials like highly branched PP.The enhancement interfacial interaction between the UFBR particles and PP matrix accounting for the rheological behavior of compatibilized blends and effectiveness of PP-g-MA were proposed and proved.
文摘The metabolic activity of the fruits continues even after harvest,which results in the loss of bioactive compounds,a decrease in the quality of the fruits,softening and browning,among other negative effects.The use of certain elements such as silicon can improve postharvest quality,since it is involved in the metabolic,physiological and structural activity of plants,moreover can increase the quality of the fruits.In addition,nanotechnology has had a positive impact on crop yield,nutritional value,fruit quality and can improve antioxidant activity.For these reasons,the use of beneficial elements such as silicon in the form of nanoparticles can be a viable option to improve the characteristics of the fruits.In the present study was evaluated the application of potassium silicate(125,250 and 500 mg L^(−1))and SiO_(2) nanoparticles(125,250 and 500 mg L^(−1))during the development of the crop.The results showed that the application of silicon(potassium silicate and silicon nanoparticles)increased the content of total soluble solids(up to 15.6%higher than control),titratable acidity(up to 38.8%higher than control),vitamin C(up to 78.2%higher than control),phenols(up to 22%higher than control),flavonoids(up to 64.6%higher than control),and antioxidant activity in lipophilic compounds(up to 56.2%higher than control).This study suggests that the use of silicon can be a good option to increase the content of bioactive compounds in cucumber fruits when they are applied during the development of the crop.
