This paper summarizes a nontoxic Anti-fouling coating utilizing capsaicin as an anti-fouling agent. The capsaicin constituent used in the coating has a rating from about 100 000 to about 1 500 000 Scoville Heat Units....This paper summarizes a nontoxic Anti-fouling coating utilizing capsaicin as an anti-fouling agent. The capsaicin constituent used in the coating has a rating from about 100 000 to about 1 500 000 Scoville Heat Units. The capsaicin is mixed with a silicon dioxide and then solubilized into a free-flowing homogeneous liquid oleoresin composition by adding a solvent to increase solubility and facilitate mixing. The oleoresin capsaicin liquid solution is mixed with a suitable corrosion resistant epoxy resin, which is then mixed with a hardening catalyst and applied to the surface to be treated.展开更多
In the present study, we optimized the procedures to pretreat the parental material, to collect, sterilize and inoculate the explants in the tissue culture of Ar- disia mamillata Hance, so that more effective sterile ...In the present study, we optimized the procedures to pretreat the parental material, to collect, sterilize and inoculate the explants in the tissue culture of Ar- disia mamillata Hance, so that more effective sterile explants can be obtained. The results revealed the optimal procedures. In detail, the parental materials were trans- ferred and pretreated in laboratory in February. The stem tips of new branches were collected in middle March, cleaned with eradicator and then rinsed with tap water for 1-2 h. After that, the explants were surface sterilized with 70% alcohol for 30 s, rinsed with sterile water 2-3 times, sterilized with 0.1% mercuric chloride for 4 min, rinsed with sterile water three times and sterilized with 0.1% mercuric chlo- ride for 4 min again. Finally, they were inoculated into medium after being rinsed with sterile water 5-8 times. By this method, the pollution rate of explants can be greatly reduced while their survival rate can be significantly improved.展开更多
Poly (EA-MAn-APTES)/silica hybrid materials were successfully prepared fromEthyl acrylate (EA), maleic anhydride (MAn) and tetraethoxysilane (TEOS) in the presence of acoupling agent 3-aminopropyltriethoxysilane (APTE...Poly (EA-MAn-APTES)/silica hybrid materials were successfully prepared fromEthyl acrylate (EA), maleic anhydride (MAn) and tetraethoxysilane (TEOS) in the presence of acoupling agent 3-aminopropyltriethoxysilane (APTES),by free-radical solution polymerization and insitu sol-gel process. The mass fraction of TEOS varied from 0 to 25%. The hybrid materials werecharacterized by the methods of FT-IR spectra, solvent extraction, scanning electron microscope (SEM), transmission electron microscope (TEM), differential scanning calorimetry (DSC) andthermogravimetric analysis (TGA) measuring apparatus to get their structures, gel contents,morphologies, particle sizes and thermal performances. The results show that the covalent bonds arebetween organic and inorganic phases, gel contents in the hybrid materials are much higher, theSiO_2 phase is well dispersed in the polymer matrix, silicon dioxide exist at nanoscale in thecomposites and have excellent thermal stability.展开更多
Friction stir keyholeless spot welding(FSKSW) using a retractable pin for 1.0 mm thick galvanized mild steel and 3 mm thick AZ31 B magnesium alloy in a lap configuration was investigated.The process variables were o...Friction stir keyholeless spot welding(FSKSW) using a retractable pin for 1.0 mm thick galvanized mild steel and 3 mm thick AZ31 B magnesium alloy in a lap configuration was investigated.The process variables were optimized in terms of the joint strength.The effects of the stacking sequence on joint formation and the joining mechanism of FSKSW AZ31B-to-mild steel joints were also analyzed.It shows that the process window and joint strength are strongly influenced by the stacking sequence of the workpieces.While the process window is narrow and unstable for FSKSW of a magnesium-to-steel stack-up,a desirable process was established for the steel-to-magnesium stacking sequence,a desirable process and higher strength joint can be got when the steel-to-magnesium stacking sequence.XRD phase and EPMA analyses of the FSKSW joint showed that the intermetallic compounds are formed at the steel-to-magnesium interface,and the element diffusion between the mild steel and AZ31 B magnesium alloy revealed that the joining methods for FSKSW joints is the main mechanical joining along with certain metallurgical bonding.展开更多
The microfibril angle of seven poplar clones was determined by using X-ray diffraction technique. Microfibril angle, wood basic density, fiber length, fiber width and cellulose content were assessed for every growth r...The microfibril angle of seven poplar clones was determined by using X-ray diffraction technique. Microfibril angle, wood basic density, fiber length, fiber width and cellulose content were assessed for every growth ring at breast height for all sample trees. Significant variation in microfibril angle was observed among growth rings. Mean microfibril angle (MFA) at breast height varied from 7.8?to 28?between growth rings with cambial age and showed a consistent pith-to-bark trend of decline an-gles. Analysis of variance also indicated that there were significant differences in wood basic density, fiber length, fiber width and cellulose content between the growth rings, which had an increasing tendency from pith to bark. Correlations between MFA and examined wood properties were predominantly large and significant negative (?0.01), and the coefficients were -0.660 for cellulose content, -0.586 for fiber length, -0.516 for fiber width and -0.450 for wood basic density, respectively. Regression analysis with linear and curve estimation indicated that a quadratic function showed the largest R2 and the least standard error for describing the relationships between microfibril angle and measured wood properties, and the correlation coefficients were over -0.45 (n=125). The results from this study suggested that microfibril angle would be a good characteristic for improvement in the future breeding program of poplars.展开更多
[Objective] The research aimed to study the rapid propagation technology and establish effective clone of Hemistepta lyrata Bunge. [Method] With tender stem of Hemistepta lyrata Bunge as material, the conditions neede...[Objective] The research aimed to study the rapid propagation technology and establish effective clone of Hemistepta lyrata Bunge. [Method] With tender stem of Hemistepta lyrata Bunge as material, the conditions needed in calluses induction and differentiation, adventitious bud differentiation and radication, test tube seedling cutting and transplantation were studied. [ Result] The results showed that the optimum medium for granulated calluses induction from tender stem was MS + BA 0.3 mg/L +2,4-D 1 -1.5 mg/L, for granulated calluses and adventitious bud differentiation was MS + AgNO31.5 mg/L + BA 0.4 mg/L + NAA 0.1 mg/L. 1/2 MS + IAA 0.6 mg/L was suitable for test tube seedling rooting and regeneration, and cinder was used as transplantation and cutting substrate. [ Conclusion]This study will provide the scientific reference for choosing the feasible medium in tissue culture of Hemistepta lyrata Bunge.展开更多
A numerical method for coupled deformation between sheet metal and flexible-die was proposed. Based on the updated Lagrangian (UL) formulation, the elastoplastic deformation of sheet metal was analyzed with finite e...A numerical method for coupled deformation between sheet metal and flexible-die was proposed. Based on the updated Lagrangian (UL) formulation, the elastoplastic deformation of sheet metal was analyzed with finite element method (FEM) and the bulk deformation of flexible-die was analyzed with element-free Galerkin method (EFGM). The frictional contact between sheet metal and flexible-die was treated by the penalty function method. The sheet elastic flexible-die bulging process was analyzed with the FEM-EFGM program for coupled deformation between sheet metal and bulk flexible-die, called CDSB-FEM-EFGM for short. Compared with finite element code DEFORM-2D and experiment results, the CDSB-FEM-EFGM program is feasible. This method provides a suitable numerical method to analyze sheet flexible-die forming.展开更多
The B4C/2024Al composites were successfully produced by pressureless infiltration method, and the effects of heat treatment on phase content and mechanical properties were investigated by X-ray diffraction (XRD), sc...The B4C/2024Al composites were successfully produced by pressureless infiltration method, and the effects of heat treatment on phase content and mechanical properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and mechanical properties testing. The results show that phases of BnC/2024Al composites include B4C, Al, Al3BC, AlB2 and Al2Cu. The phase species remain unchanged; however, the phase content of the composites changes significantly after heat treatment at the temperature of 660, 700, 800 or 900 ℃ for 12, 24 or 36 h. It is found that the heat treatment results in not only considerable enhancement in hardness, but also reduction in bending strength of the composites. Heat treatment at 800 ℃ for 36 h does best to hardness of the composites, while at 700 ℃ for 36 h it is the most beneficial to their comprehensive mechanical properties.展开更多
This paper presents a new electromagnetic functional material developed byelectron-less nickel deposition technique, with a single hollow micro-sphere as the core templateand a thin nickel layer as the shell. The micr...This paper presents a new electromagnetic functional material developed byelectron-less nickel deposition technique, with a single hollow micro-sphere as the core templateand a thin nickel layer as the shell. The micrograph taken by a scanning electron microscope showsthe microstructures of the materials in detail. Scattering parameters of the waveguide sample holderfilled with the materials have been obtained over X band. The electromagnetic parameters computedfrom the measured S parameters show that the material with metallic hollow spheres has as highrelative permeability μ'_r as 19.0 with about 0.6 magnetic loss tangent over the whole bandwidth.Compared to the material with non-metallic spheres, the permeability μ'_r and the magnetic losstangent μ'_r increase greatly, while the permittivity remains lower than 1.8.展开更多
In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a func...In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a functional surface possess obvious advantages and were thus rapidly developed for cancer treatment. Many stimuli-responsive materials, such as nanopartides, polymers, and inorganic materials, have been applied as caps and gatekeepers to control drug release from MSNs. This review presents an overview of the recent progress in the production of pH-responsive MSNs based on the pH gradient between normal tissues and the tumor microenvironment. Four main categories of gatekeepers can respond to acidic conditions. These categories will be described in detail.展开更多
The heartwood of teak in certain areas of Java Island displays irregular black streaks along the annual rings. We investigated the color and chemical characteristics in a radial direction of partially black-streaked h...The heartwood of teak in certain areas of Java Island displays irregular black streaks along the annual rings. We investigated the color and chemical characteristics in a radial direction of partially black-streaked heartwood samples. Color properties (pH value, inorganic element, extractive content and extractive characterization) were measured in the color co-ordinates CIELAB system. The results show that the black streak part was 12-15 brightness (L^*) value units less than the normal heartwood. Furthermore, the black streak part had more red (a^*) but less yellow (b^*), hue (h) and chroma (C^*) than the normal wood. The pH value, ash content and calcium contents of the black streak part were slightly higher than those obtained for the normal wood. The content of the low-polar extractive (n-hexane and ethyl acetate) of the black streak part was considerably higher than that for the normal wood. The blackening process was speculated to be a kind of defense mechanism indicated by remarkable amount ofbioactive compound called tectoquinone.展开更多
The preparation technique and properties of Ag-type inorganic antibiotic material carried by Al2O3 were studied. The results show that the material has good antibiotic and safety properties, the acute toxicity taken b...The preparation technique and properties of Ag-type inorganic antibiotic material carried by Al2O3 were studied. The results show that the material has good antibiotic and safety properties, the acute toxicity taken by stomata is LD 50 >8000mg/kg (little and big white rats), and the normal quantity in subacute toxicity test is 80mg/(kg·d). The better mass fraction of doping Ag2O in antibiotic material carried by Al2O3 is 4%CD*28%, and the optimal sintering temperature is from 1000℃ to 1100℃.展开更多
By using metal nitrates as starting materials and citric acid as a complexing agent, Y2Si207:Re3+ (Re=Eu, Tb) phosphors were prepared by a sol-gel method. X-ray diffraction was employed to characterize the resulti...By using metal nitrates as starting materials and citric acid as a complexing agent, Y2Si207:Re3+ (Re=Eu, Tb) phosphors were prepared by a sol-gel method. X-ray diffraction was employed to characterize the resulting samples. The results of XRD indicate that the α-Y2Si2O7 nanocrystal with size of 27 nm is obtained at 1000 ℃ and the doping ion content does not influence the structure. The excitation spectra in the UV and VUV ranges and the emission spectra of Re^3+ doped samples were measured. The excitation spectra in the VUV range is due to absorption of host, that in the UV range is ascribed to absorption transitions from 4f to 5d state of the Tb^3+ and the charge transfer in the En^3+-O^2- bond. The spectral energy distribution of the Tb^3+ emission depends strongly on the Tb3+ concentration. The dependence of photolumineseenee intensity on Re^3+ concentration is also discussed in detail. The fluorescent decay curves at room temperature were measured and analyzed.展开更多
Narrow spectral response,low charge separation efficiency and slow water oxidation kinetics of TiO_(2)limit its application in photoelectrochemical and photocatalytic water splitting.Herein,a promising organic/inorgan...Narrow spectral response,low charge separation efficiency and slow water oxidation kinetics of TiO_(2)limit its application in photoelectrochemical and photocatalytic water splitting.Herein,a promising organic/inorganic composite catalyst Ag/PANI/3DOMM‐TiO_(2–x)with a three‐dimensional ordered macro‐and meso‐porous(3DO MM)structure,oxygen vacancy and Ti^(3+)defects,heterojunction formation and noble metal Ag was designed based on the Z‐scheme mechanism and successfully prepared.The Ag/PANI/3DOMM‐TiO_(2–x)ternary catalyst exhibited enhanced hydrogen production activity in both photocatalytic and photoelectrochemical water splitting.The photocatalytic hydrogen production rate is 420.90μmol g^(–1)h^(–1),which are 19.80 times and 2.06 times higher than the commercial P25 and 3DOMM‐TiO_(2),respectively.In the photoelectrochemical tests,the Ag/PANI/3DOMM‐TiO_(2–x)photoelectrode shows enhanced separation and transfer of carriers with a high current density of 1.55 mA cm^(–2)at equilibrium potential of 1.23 V under simulated AM 1.5 G illumination,which is approximately 5 times greater than the 3DOMM‐TiO_(2).The present work has demonstrated the promising potential of organic/inorganic Z‐scheme photocatalyst in driving water splitting for hydrogen production.展开更多
The wood basic density, cellulose content and fiber form were investigated for all sample trees at breast height (1.3 m) in seven poplar clones, and at 0 (butt), 5.6, 9.6, 13.6, 17.6, 19.6 and 21.6 m for clone Nanlin-...The wood basic density, cellulose content and fiber form were investigated for all sample trees at breast height (1.3 m) in seven poplar clones, and at 0 (butt), 5.6, 9.6, 13.6, 17.6, 19.6 and 21.6 m for clone Nanlin-95 and Nanlin-895, respectively, for providing information on variation patterns of wood density, fiber characteristics and holocellulose content within trees and among clones. The results showed that significant variations about wood density, cellulose content, fiber diameter and the ratio of fiber length to diameter existed among poplar clones examined. Variance analysis indicated that there were significant differences in wood basic density, fiber length, fiber diameter and cellulose content among the growth rings, which had an increasing tendency along the direction from pith to bark. The significant differences also existed in wood basic density, fiber length and fiber diameter at different tree height. The mean wood basic density had a general increase trend with increasing height of trees and the lowest was found at the base, while fiber length and fiber diameter had a general decline pattern with increasing height of trees and the biggest value was observed at the height of 5.6 m. Regression analysis indicated that the relationship between examined wood properties and growth ring number (cambial age), and the relationship between examined wood properties and tree height can be described by polynomial functions.展开更多
A novel Sn-2.5Ag-2.0Ni alloy was used for soldering SiCp/Al composites substrate deposited with electroless Ni(5%P) (mass fraction)and Ni(10%P)(mass fraction)layers.It is observed that variation of P contents in the e...A novel Sn-2.5Ag-2.0Ni alloy was used for soldering SiCp/Al composites substrate deposited with electroless Ni(5%P) (mass fraction)and Ni(10%P)(mass fraction)layers.It is observed that variation of P contents in the electroless Ni(P)layer results in different types of microstructures of SnAgNi/Ni(P)solder joint.The morphology of Ni3Sn4 intermetallic compounds(IMCs)formed between the solder and Ni(10%P)layer is observed to be needle-like and this shape provides high speed diffusion channels for Ni to diffuse into solder that culminates in high growth rate of Ni3Sn4.The diffusion of Ni into solder furthermore results in the formation of Kirkendall voids at the interface of Ni(P)layer and SiCp/Al composites substrate.It is observed that solder reliability is degraded by the formation of Ni2SnP,P rich Ni layer and Kirkendall voids.The compact Ni3Sn4 IMC layer in Ni(5%P)solder joint prevents Ni element from diffusing into solder,resulting in a low growth rate of Ni3Sn4 layer.Meanwhile,the formation of Ni2SnP that significantly affects the reliability of solder joints is suppressed by the low P content Ni(5%P)layer.Thus,shear strength of Ni(5%P) solder joint is concluded to be higher than that of Ni(10%P)solder joint.Growth of Ni3Sn4 IMC layer and formation of crack are accounted to be the major sources of the failure of Ni(5%P)solder joint.展开更多
文摘This paper summarizes a nontoxic Anti-fouling coating utilizing capsaicin as an anti-fouling agent. The capsaicin constituent used in the coating has a rating from about 100 000 to about 1 500 000 Scoville Heat Units. The capsaicin is mixed with a silicon dioxide and then solubilized into a free-flowing homogeneous liquid oleoresin composition by adding a solvent to increase solubility and facilitate mixing. The oleoresin capsaicin liquid solution is mixed with a suitable corrosion resistant epoxy resin, which is then mixed with a hardening catalyst and applied to the surface to be treated.
基金Supported by the Research Funds of Jiangsu Open University/the City Vocational College of Jiangsu during the 12th Five-Year Plan Period(12SEW-Y-026)~~
文摘In the present study, we optimized the procedures to pretreat the parental material, to collect, sterilize and inoculate the explants in the tissue culture of Ar- disia mamillata Hance, so that more effective sterile explants can be obtained. The results revealed the optimal procedures. In detail, the parental materials were trans- ferred and pretreated in laboratory in February. The stem tips of new branches were collected in middle March, cleaned with eradicator and then rinsed with tap water for 1-2 h. After that, the explants were surface sterilized with 70% alcohol for 30 s, rinsed with sterile water 2-3 times, sterilized with 0.1% mercuric chloride for 4 min, rinsed with sterile water three times and sterilized with 0.1% mercuric chlo- ride for 4 min again. Finally, they were inoculated into medium after being rinsed with sterile water 5-8 times. By this method, the pollution rate of explants can be greatly reduced while their survival rate can be significantly improved.
文摘Poly (EA-MAn-APTES)/silica hybrid materials were successfully prepared fromEthyl acrylate (EA), maleic anhydride (MAn) and tetraethoxysilane (TEOS) in the presence of acoupling agent 3-aminopropyltriethoxysilane (APTES),by free-radical solution polymerization and insitu sol-gel process. The mass fraction of TEOS varied from 0 to 25%. The hybrid materials werecharacterized by the methods of FT-IR spectra, solvent extraction, scanning electron microscope (SEM), transmission electron microscope (TEM), differential scanning calorimetry (DSC) andthermogravimetric analysis (TGA) measuring apparatus to get their structures, gel contents,morphologies, particle sizes and thermal performances. The results show that the covalent bonds arebetween organic and inorganic phases, gel contents in the hybrid materials are much higher, theSiO_2 phase is well dispersed in the polymer matrix, silicon dioxide exist at nanoscale in thecomposites and have excellent thermal stability.
基金Project (10902047,51265030) supported by the National Natural Science Foundation of China
文摘Friction stir keyholeless spot welding(FSKSW) using a retractable pin for 1.0 mm thick galvanized mild steel and 3 mm thick AZ31 B magnesium alloy in a lap configuration was investigated.The process variables were optimized in terms of the joint strength.The effects of the stacking sequence on joint formation and the joining mechanism of FSKSW AZ31B-to-mild steel joints were also analyzed.It shows that the process window and joint strength are strongly influenced by the stacking sequence of the workpieces.While the process window is narrow and unstable for FSKSW of a magnesium-to-steel stack-up,a desirable process was established for the steel-to-magnesium stacking sequence,a desirable process and higher strength joint can be got when the steel-to-magnesium stacking sequence.XRD phase and EPMA analyses of the FSKSW joint showed that the intermetallic compounds are formed at the steel-to-magnesium interface,and the element diffusion between the mild steel and AZ31 B magnesium alloy revealed that the joining methods for FSKSW joints is the main mechanical joining along with certain metallurgical bonding.
基金This research was supported by National Natural Science Foundation of China (Grant No. 30070616).
文摘The microfibril angle of seven poplar clones was determined by using X-ray diffraction technique. Microfibril angle, wood basic density, fiber length, fiber width and cellulose content were assessed for every growth ring at breast height for all sample trees. Significant variation in microfibril angle was observed among growth rings. Mean microfibril angle (MFA) at breast height varied from 7.8?to 28?between growth rings with cambial age and showed a consistent pith-to-bark trend of decline an-gles. Analysis of variance also indicated that there were significant differences in wood basic density, fiber length, fiber width and cellulose content between the growth rings, which had an increasing tendency from pith to bark. Correlations between MFA and examined wood properties were predominantly large and significant negative (?0.01), and the coefficients were -0.660 for cellulose content, -0.586 for fiber length, -0.516 for fiber width and -0.450 for wood basic density, respectively. Regression analysis with linear and curve estimation indicated that a quadratic function showed the largest R2 and the least standard error for describing the relationships between microfibril angle and measured wood properties, and the correlation coefficients were over -0.45 (n=125). The results from this study suggested that microfibril angle would be a good characteristic for improvement in the future breeding program of poplars.
文摘[Objective] The research aimed to study the rapid propagation technology and establish effective clone of Hemistepta lyrata Bunge. [Method] With tender stem of Hemistepta lyrata Bunge as material, the conditions needed in calluses induction and differentiation, adventitious bud differentiation and radication, test tube seedling cutting and transplantation were studied. [ Result] The results showed that the optimum medium for granulated calluses induction from tender stem was MS + BA 0.3 mg/L +2,4-D 1 -1.5 mg/L, for granulated calluses and adventitious bud differentiation was MS + AgNO31.5 mg/L + BA 0.4 mg/L + NAA 0.1 mg/L. 1/2 MS + IAA 0.6 mg/L was suitable for test tube seedling rooting and regeneration, and cinder was used as transplantation and cutting substrate. [ Conclusion]This study will provide the scientific reference for choosing the feasible medium in tissue culture of Hemistepta lyrata Bunge.
基金Project(51275130)supported by the National Natural Science Foundation of China
文摘A numerical method for coupled deformation between sheet metal and flexible-die was proposed. Based on the updated Lagrangian (UL) formulation, the elastoplastic deformation of sheet metal was analyzed with finite element method (FEM) and the bulk deformation of flexible-die was analyzed with element-free Galerkin method (EFGM). The frictional contact between sheet metal and flexible-die was treated by the penalty function method. The sheet elastic flexible-die bulging process was analyzed with the FEM-EFGM program for coupled deformation between sheet metal and bulk flexible-die, called CDSB-FEM-EFGM for short. Compared with finite element code DEFORM-2D and experiment results, the CDSB-FEM-EFGM program is feasible. This method provides a suitable numerical method to analyze sheet flexible-die forming.
基金Project(2011CB605805)supported by the National Basic Research Program of China
文摘The B4C/2024Al composites were successfully produced by pressureless infiltration method, and the effects of heat treatment on phase content and mechanical properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and mechanical properties testing. The results show that phases of BnC/2024Al composites include B4C, Al, Al3BC, AlB2 and Al2Cu. The phase species remain unchanged; however, the phase content of the composites changes significantly after heat treatment at the temperature of 660, 700, 800 or 900 ℃ for 12, 24 or 36 h. It is found that the heat treatment results in not only considerable enhancement in hardness, but also reduction in bending strength of the composites. Heat treatment at 800 ℃ for 36 h does best to hardness of the composites, while at 700 ℃ for 36 h it is the most beneficial to their comprehensive mechanical properties.
文摘This paper presents a new electromagnetic functional material developed byelectron-less nickel deposition technique, with a single hollow micro-sphere as the core templateand a thin nickel layer as the shell. The micrograph taken by a scanning electron microscope showsthe microstructures of the materials in detail. Scattering parameters of the waveguide sample holderfilled with the materials have been obtained over X band. The electromagnetic parameters computedfrom the measured S parameters show that the material with metallic hollow spheres has as highrelative permeability μ'_r as 19.0 with about 0.6 magnetic loss tangent over the whole bandwidth.Compared to the material with non-metallic spheres, the permeability μ'_r and the magnetic losstangent μ'_r increase greatly, while the permittivity remains lower than 1.8.
基金supported by the Chinese Natural Science Foundation Project (Grant No. 30970784 and 81171455)a National Distinguished Young Scholars Grant (Grant No. 31225009) from the National Natural Science Foundation of China+5 种基金the National Key Basic Research Program of China (Grant No. 2009CB930200)the Chinese Academy of Sciences (CAS) ‘Hundred Talents Program’ (Grant No. 07165111ZX)the CAS Knowledge Innovation Program, and the State HighTech Development Plan (Grant No. 2012AA020804)the ‘Strategic Priority Research Program’ of the Chinese Academy of Sciences (Grant No. XDA09030301)NIH/NIMHD 8 G12 MD007597USAMRMC W81XWH-10-1-0767 grants
文摘In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a functional surface possess obvious advantages and were thus rapidly developed for cancer treatment. Many stimuli-responsive materials, such as nanopartides, polymers, and inorganic materials, have been applied as caps and gatekeepers to control drug release from MSNs. This review presents an overview of the recent progress in the production of pH-responsive MSNs based on the pH gradient between normal tissues and the tumor microenvironment. Four main categories of gatekeepers can respond to acidic conditions. These categories will be described in detail.
基金supported by the Ministry of Educa-tion, Culture, Sports, Science and Technology in Japan.
文摘The heartwood of teak in certain areas of Java Island displays irregular black streaks along the annual rings. We investigated the color and chemical characteristics in a radial direction of partially black-streaked heartwood samples. Color properties (pH value, inorganic element, extractive content and extractive characterization) were measured in the color co-ordinates CIELAB system. The results show that the black streak part was 12-15 brightness (L^*) value units less than the normal heartwood. Furthermore, the black streak part had more red (a^*) but less yellow (b^*), hue (h) and chroma (C^*) than the normal wood. The pH value, ash content and calcium contents of the black streak part were slightly higher than those obtained for the normal wood. The content of the low-polar extractive (n-hexane and ethyl acetate) of the black streak part was considerably higher than that for the normal wood. The blackening process was speculated to be a kind of defense mechanism indicated by remarkable amount ofbioactive compound called tectoquinone.
文摘The preparation technique and properties of Ag-type inorganic antibiotic material carried by Al2O3 were studied. The results show that the material has good antibiotic and safety properties, the acute toxicity taken by stomata is LD 50 >8000mg/kg (little and big white rats), and the normal quantity in subacute toxicity test is 80mg/(kg·d). The better mass fraction of doping Ag2O in antibiotic material carried by Al2O3 is 4%CD*28%, and the optimal sintering temperature is from 1000℃ to 1100℃.
文摘By using metal nitrates as starting materials and citric acid as a complexing agent, Y2Si207:Re3+ (Re=Eu, Tb) phosphors were prepared by a sol-gel method. X-ray diffraction was employed to characterize the resulting samples. The results of XRD indicate that the α-Y2Si2O7 nanocrystal with size of 27 nm is obtained at 1000 ℃ and the doping ion content does not influence the structure. The excitation spectra in the UV and VUV ranges and the emission spectra of Re^3+ doped samples were measured. The excitation spectra in the VUV range is due to absorption of host, that in the UV range is ascribed to absorption transitions from 4f to 5d state of the Tb^3+ and the charge transfer in the En^3+-O^2- bond. The spectral energy distribution of the Tb^3+ emission depends strongly on the Tb3+ concentration. The dependence of photolumineseenee intensity on Re^3+ concentration is also discussed in detail. The fluorescent decay curves at room temperature were measured and analyzed.
文摘Narrow spectral response,low charge separation efficiency and slow water oxidation kinetics of TiO_(2)limit its application in photoelectrochemical and photocatalytic water splitting.Herein,a promising organic/inorganic composite catalyst Ag/PANI/3DOMM‐TiO_(2–x)with a three‐dimensional ordered macro‐and meso‐porous(3DO MM)structure,oxygen vacancy and Ti^(3+)defects,heterojunction formation and noble metal Ag was designed based on the Z‐scheme mechanism and successfully prepared.The Ag/PANI/3DOMM‐TiO_(2–x)ternary catalyst exhibited enhanced hydrogen production activity in both photocatalytic and photoelectrochemical water splitting.The photocatalytic hydrogen production rate is 420.90μmol g^(–1)h^(–1),which are 19.80 times and 2.06 times higher than the commercial P25 and 3DOMM‐TiO_(2),respectively.In the photoelectrochemical tests,the Ag/PANI/3DOMM‐TiO_(2–x)photoelectrode shows enhanced separation and transfer of carriers with a high current density of 1.55 mA cm^(–2)at equilibrium potential of 1.23 V under simulated AM 1.5 G illumination,which is approximately 5 times greater than the 3DOMM‐TiO_(2).The present work has demonstrated the promising potential of organic/inorganic Z‐scheme photocatalyst in driving water splitting for hydrogen production.
基金This study was supported by National Natural Science Foundation of China, (No. 30070616).
文摘The wood basic density, cellulose content and fiber form were investigated for all sample trees at breast height (1.3 m) in seven poplar clones, and at 0 (butt), 5.6, 9.6, 13.6, 17.6, 19.6 and 21.6 m for clone Nanlin-95 and Nanlin-895, respectively, for providing information on variation patterns of wood density, fiber characteristics and holocellulose content within trees and among clones. The results showed that significant variations about wood density, cellulose content, fiber diameter and the ratio of fiber length to diameter existed among poplar clones examined. Variance analysis indicated that there were significant differences in wood basic density, fiber length, fiber diameter and cellulose content among the growth rings, which had an increasing tendency along the direction from pith to bark. The significant differences also existed in wood basic density, fiber length and fiber diameter at different tree height. The mean wood basic density had a general increase trend with increasing height of trees and the lowest was found at the base, while fiber length and fiber diameter had a general decline pattern with increasing height of trees and the biggest value was observed at the height of 5.6 m. Regression analysis indicated that the relationship between examined wood properties and growth ring number (cambial age), and the relationship between examined wood properties and tree height can be described by polynomial functions.
基金Projects(50274014, 50774005) supported by the National Natural Science Foundation of ChinaProject(2006CB605207) supported by the National Basic Research Program of China+1 种基金Project(2006AA03Z557) supported by the National High-tech Research and Development of ChinaProject(I2P407) supported by MOE Program for Changjiang Scholars
文摘A novel Sn-2.5Ag-2.0Ni alloy was used for soldering SiCp/Al composites substrate deposited with electroless Ni(5%P) (mass fraction)and Ni(10%P)(mass fraction)layers.It is observed that variation of P contents in the electroless Ni(P)layer results in different types of microstructures of SnAgNi/Ni(P)solder joint.The morphology of Ni3Sn4 intermetallic compounds(IMCs)formed between the solder and Ni(10%P)layer is observed to be needle-like and this shape provides high speed diffusion channels for Ni to diffuse into solder that culminates in high growth rate of Ni3Sn4.The diffusion of Ni into solder furthermore results in the formation of Kirkendall voids at the interface of Ni(P)layer and SiCp/Al composites substrate.It is observed that solder reliability is degraded by the formation of Ni2SnP,P rich Ni layer and Kirkendall voids.The compact Ni3Sn4 IMC layer in Ni(5%P)solder joint prevents Ni element from diffusing into solder,resulting in a low growth rate of Ni3Sn4 layer.Meanwhile,the formation of Ni2SnP that significantly affects the reliability of solder joints is suppressed by the low P content Ni(5%P)layer.Thus,shear strength of Ni(5%P) solder joint is concluded to be higher than that of Ni(10%P)solder joint.Growth of Ni3Sn4 IMC layer and formation of crack are accounted to be the major sources of the failure of Ni(5%P)solder joint.