Phospahting coated WE43 magnesium alloy was prepared by an immersion method. The microstructure, corrosion resistance and biocompatibility of the coated alloy were investigated. Scanning electron microscopy (SEM) an...Phospahting coated WE43 magnesium alloy was prepared by an immersion method. The microstructure, corrosion resistance and biocompatibility of the coated alloy were investigated. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to examine the microstructure and the composition of the coated alloy. The corrosion resistance was studied by means of potentiodynamic polarization method and the biocompatibility of the surface modified WE43 alloy was evaluated by (3-(4,5)-Dimethylthiazol-2, yl)-2,5-diphenyltetrazolium bromide (MTT) and hemolysis test. The results show that the phosphating coating can enhance the corrosion resistance of WE43 alloy and can be a good candidate to increase the biocompatibility of WE43 alloy.展开更多
A set of stacked ribbons with the composition of Fe77Ga23 were prepared with different wheel velocities of 7 m/s, 12.5 m/s and 25 m/s(named as S7, S12.5 and S25, respectively). High resolution X-ray diffraction patt...A set of stacked ribbons with the composition of Fe77Ga23 were prepared with different wheel velocities of 7 m/s, 12.5 m/s and 25 m/s(named as S7, S12.5 and S25, respectively). High resolution X-ray diffraction patterns of these ribbons show that all the ribbons present the disordered A2 structure, whereas an additional modified-DO3 phase is detected in S12.5 and S25. S25 has stronger(100) texture than other two samples. Ga K-edge extended X-ray absorption fine structure results indicate that both bond distance and the number of Ga atoms in the second neighbor shell around Ga decrease with increasing wheel velocity. No Ga cluster is detected in the studied ribbons. A short-range ordering Ga-rich phase and large local strain have no obvious influence on magnetostriction of S7. It is believed that both the(100) texture and the additional modified-DO3 phase play a positive role in magnetostrictive properties of Fe77Ga23 ribbons.展开更多
A semantics-based model is proposed to enable weakened hedges, such as "more or less" and "roughly" in the context of linguistic multi-criteria decision making. First, the resemblance relations are defined based o...A semantics-based model is proposed to enable weakened hedges, such as "more or less" and "roughly" in the context of linguistic multi-criteria decision making. First, the resemblance relations are defined based on the semantics of terms on the domain. Then, the hedges can be represented after the upper and loose upper approximations of a linguistic term are derived. Accordingly, some compact formulae can be derived for the semantics of linguistic expressions with hedges. Parameters in these formulae are objectively determined according to the semantics of original terms. The proposed model presents a more natural way to express the decision information under uncertainties and its semantics is clear. The proposed model is clarified by solving the problem of evaluation and selection of sustainable innovative energy technologies. Computational results demonstrate that the model can deal with various uncertainties of the problem. Finally, the model is compared with existing techniques and extended to the case when the semantics of terms are represented by trapezoidal fuzzy numbers.展开更多
This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantiti...This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantities of this system in equilibrium are obtained.展开更多
To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and sl...To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and slenderspindle short shoot in Xingtang County of Hebai Province were investigated, then by SPSS anal- ysis, the correlations between the taperingness and each growth factor of inserted small branch were compared. The results showed that the taperingness of central trunk of free spindle dwarf-shoot Fuji apple treeshad negative correlations with each factor of inserted small branch, while the taperingness of central trunk of free spin- dle long-shoot Fuji apple treeshad positive correlations with each factor of inserted small branch, the taperingness of central trunk of slenderspindle short-shootFuji ap- ple treeshad negative correlation with total thickness of inserted small branch, but had positive correlations with other factors. This study can provide a scientifictheo- retical basis for the pruning technology of high-density planting trees grafting by dwarfing self-rooted rootstock.展开更多
The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral co...The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral correction technique (MSASC). The aggregation of AABB on CTAB followed the Langmuir isothermal adsorption law. The enrichment of AABB on CTAB sensitized the complexation between Cu(Ⅱ) or Ni(Ⅱ)and AABB. The binding ratio of AABB to CTAB was 1:2.5, and monomeric aggregate, AABB2CTAB5, was formed with an adsorption constant of 5.95×10^5 at 20 ℃ or 2.48×10^5 at 40 ℃. In the ternary complexation, the ratio of AABB:Cu and AABB:Ni were 1:1 and 1:2.5, respectively. Two types of aggregates, Cu2.AABB2·CTAB80 and Ni5.AABB2.CTAB80, were formed.展开更多
We present an approach to solve Bethe-Salpeter (BS) equations exactly withoutany approximation if the kernel of the BS equations exactly is instantaneous, and take positroniumas an example to illustrate the general fe...We present an approach to solve Bethe-Salpeter (BS) equations exactly withoutany approximation if the kernel of the BS equations exactly is instantaneous, and take positroniumas an example to illustrate the general features of the exact solutions. The key step for theapproach is from the BS equations to derive a set of coupled and well-determined integrationequations in linear eigenvalue for the components of the BS wave functions equivalently, which maybe solvable numerically under a controlled accuracy, even though there is no analytic solution. Forpositronium, the exact solutions precisely present corrections to those of the correspondingSchrodinger equation in order υ~1 (υ is the relative velocity) for eigenfunctions, in order υ~2for eigenvalues, and the mixing between S and D components in J~(PC) = 1~(--) states etc.,quantitatively. Moreover, we also point out that there is a questionable step in some existentderivations for the instantaneous BS equations if one is pursuing the exact solutions. Finally, weemphasize that one should take the O(υ) corrections emerging in the exact solutions into accountaccordingly if one is interested in the relativistic corrections for relevant problems to the boundstates.展开更多
In order to explore the influence of modification sites of functional groups on landfill gas (CO2/CH4) separation performance of metal-organic frameworks (MOFs), six types of or- ganic linkers and three types of f...In order to explore the influence of modification sites of functional groups on landfill gas (CO2/CH4) separation performance of metal-organic frameworks (MOFs), six types of or- ganic linkers and three types of functional groups (i.e. -F, -NH2, -CH3) were used to construct 36 MOFs of pcu topology based on copper paddlewheel. Grand canonical Monte Carlo sim- ulations were performed in this work to evaluate the separation performance of MOFs at low (vacuum swing adsorption) and high (pressure swing adsorption) pressures, respectively. Simulation results demonstrated that CO2 working capacity of the unfunctionalized MOFs generally exhibits pore-size dependence at 1 bar, which increases with the decrease in pore sizes. It was also found that -NH2 funetionalized MOFs exhibit the highest CO2 uptake due to the enhanced Coulombic interactions between the polar -NH2 groups and the quadrupole moment of CO2 molecules, which is followed by -CH3 and -F functionalized ones. Moreover, positioning the functional groups -NH2 and -CH3 at sites far from the metal node (site b) exhibits more significant enhancement on CO2/CH4 separation performance compared to that adjacent to the metal node (site a).展开更多
In this study,an acid-induced assembly strategy for a rutile TiO2 photocatalyst was proposed on the basis of the treatment of lamellar protonated titanate with a concentrated HNO3 solution.Nitrate groups were successf...In this study,an acid-induced assembly strategy for a rutile TiO2 photocatalyst was proposed on the basis of the treatment of lamellar protonated titanate with a concentrated HNO3 solution.Nitrate groups were successfully grafted onto a TiO2 surface and induced the assembly of rutile TiO2 nanorods into uniform spindle-like nanobundles.The resulting TiO2 product achieved a photocatalytic hydrogen evolution rate of 402.4μmol h^?1,which is 3.1 times higher than that of Degussa P25-TiO2.It was demonstrated that nitrate group grafting caused the rutile TiO2 surface to become negatively charged,which is favorable for trapping positive protons and improving charge carrier separation,thereby enhancing photocatalytic hydrogen production.Additionally,surface charges were crucial to structural stability based on electrostatic repulsion.This study not only developed a facile surface modification strategy for fabricating efficient H2 production photocatalysts but also identified an influence mechanism of inorganic acids different from that reported in the literature.展开更多
Permacol mesh has shown promise when used in abdominal wall repair,especially in the presence of a contaminated surgical field.This biomaterial,derived from porcine dermis collagen,has proposed advantages over synthet...Permacol mesh has shown promise when used in abdominal wall repair,especially in the presence of a contaminated surgical field.This biomaterial,derived from porcine dermis collagen,has proposed advantages over synthetic materials due to increased biocompatibility and reduced foreign body reaction within human tissues.However,we present a case report describing a patient who displayed rejection to a Permacol mesh when used in the repair of abdominal wound dehiscence following an emergency laparotomy.Review of the English language literature using PubMed and Medline, showed only two previously published cases of explantation of Permacoldue to sepsis or wound breakdown. The authors believe this is the first case of severe foreign body reaction leading to rejection of Permacol.Both animal and human studies show conflicting evidence of biocompatibility.There are several reports of successful use of Permacolto repair complex incisional herniae or abdominal walls in the presence of significant contamination.It appears from the literature that Permacolis a promising material,but as we have demonstrated,it has the potential to evoke a foreign body reaction and rejection in certain subjects.展开更多
Covalent organic framework (COF) is a porous material with low density and large BET (Brtmauer-Emmett-Teller) surface area. They have great potential in gas adsorption and separation. In this work, the adsorption ...Covalent organic framework (COF) is a porous material with low density and large BET (Brtmauer-Emmett-Teller) surface area. They have great potential in gas adsorption and separation. In this work, the adsorption of pure CO2 and CO2/CH4 mixture on modified COF-102 was simulated by using GCMC (grand canonical Monte Carlo). Metal Li was incorporated into COF-102 through three doping methods, including charge exchange, O^--Li6+ dipolar interaction and O^--Li^+ chemical bonding. The influence of Li doping on the adsorption of CO2 was studied. The results showed that among the three methods, the dipole doping is the best way to improve CO2 adsorption performance. Further, the ligands of COF-102 were replaced by extended aromatic moieties, such as diphenyl and pyrene. The adsorption capacity of CO2 and CH4, and the selectivity of CO2/CH4 on the ligand-replaced COF-102 were studied. The capacity of CO2 and CH4 on the ligand-replaced COF-102 had obvious changes; hence the selectivity of CO2/CH4 can be adjusted accordingly.展开更多
Phase diverse speckle is a novel kind of imaging technique and can be used to overcome image degradation from unknown phase aberrations, such as atmospheric turbulence. The wave-front phase expanded on the Zernike pol...Phase diverse speckle is a novel kind of imaging technique and can be used to overcome image degradation from unknown phase aberrations, such as atmospheric turbulence. The wave-front phase expanded on the Zernike polynomials is esti- mated from a pair of images (in the focal and out of focus planes). In this paper the principle of PDS is analyzed, and genetic algorithm is used as the iterative algorithm to simulate some characteristics, such as the influence of Zernike polynomials’ mode, amplitude of turbulence on the phase estimation. Thus, a new method for recovery of images is explored.展开更多
The effects of heat treatment and strontium (SO addition on the microstructure and mechanical properties of ADC12 alloys were investigated, and two-stage solution treatment was introduced. The results indicated that ...The effects of heat treatment and strontium (SO addition on the microstructure and mechanical properties of ADC12 alloys were investigated, and two-stage solution treatment was introduced. The results indicated that the addition of Sr obviously refined the microstructure of ADC12 alloys. When 0.05 wt% Sr was added into the alloy, the eutectic Si phase was fully modified into fine fibrous structure; a-A1 and fl-A15FeSi phases were best refined; and the eutectic AlzCu phase was modified into block-like AlzCu phase that continuously distributed at the grain boundary. The ultimate tensile strength (UTS) (270.63 MPa) and elongation (3.19%) were increased by 51.2% and 73.4% respectively compared with unmodified alloys. After the two-stage solution treatment (500 ~C, 6 h+520 ~C, 4 h), for 0.05 wt% Sr modified ADC12 alloys, the Si phases transformed into fine particle structure and AlzCu phases were fully dissolved. The peak hardness value of the alloys processed by the two-stage solution treatment was increased by 8.3% and 6.8% respectively compared to solution treatment at 500 ~C and 520 ~C. After the aging treatment (175 ~C, 7 h), the hardness and UTS were increased by 38.73% and 13.96% respectively when compared with the unmodified alloy.展开更多
Heterogeneous photocatalysis,an advanced oxidation process,has garnered extensive attention in the field of environmental remediation because it involves the direct utilization of solar energy for the removal of numer...Heterogeneous photocatalysis,an advanced oxidation process,has garnered extensive attention in the field of environmental remediation because it involves the direct utilization of solar energy for the removal of numerous pollutants.However,the application of heterogeneous photocatalysis in environmental remediation has not achieved the expected consequences due to enormous challenges such as low photocatalytic efficiencies and high costs of heterogeneous photocatalysts in large-scale practical applications.Furthermore,pollutants in the natural environment,including water,air,and solid phases,are diverse and complex.Therefore,extensive efforts should be made to better understand and apply heterogeneous photocatalysis for environmental remediation.Herein,the fundamentals of heterogeneous photocatalysis for environmental remediation are introduced.Then,potential semiconductors and their modification strategies for environmental photocatalysis are systematically presented.Finally,conclusions and prospects are briefly summarized,and the direction for the future development of environmental photocatalysis is explored.This review may provide reference directions toward understanding,researching,and designing photocatalytic remediation systems for various environmental pollutants.展开更多
The multi-configuration Dirac-Fock method is used in this work to calculate ground-state ionization potentials of Boron and Carbon isoelectronic sequences from Z = 6 to Z=42. And the contribution of relativistic corre...The multi-configuration Dirac-Fock method is used in this work to calculate ground-state ionization potentials of Boron and Carbon isoelectronic sequences from Z = 6 to Z=42. And the contribution of relativistic corrections, nuclear volume effect, Breit and QED effects to tile results is discussed in the calculation. The results are compared with the scanty existing theoretical and experimental data in the literature and good agreements are achieved. Then analytical expressions of lonization potential along Boron and Carbon isoelectronic sequences are obtained.展开更多
The application of mixed powders with different mass fraction on laser additive repairing(LAR)can be an effective way to guarantee the performance and functionality of repaired part in time.A convenient and feasible a...The application of mixed powders with different mass fraction on laser additive repairing(LAR)can be an effective way to guarantee the performance and functionality of repaired part in time.A convenient and feasible approach is presented to repair TA15 forgings by employing Ti6Al4V-xTA15 mixed powders in this paper.The performance compatibility of Ti6Al4V-xTA15 powders from the aspects of microhardness,tensile property,heat capacity,thermal expansion coefficient and corrosion resistance with the TA15 forgings was fully investigated.The primaryαlaths were refined and the volume fraction of the secondaryαphase was increased by increasing the mass fraction of TA15 in the mixed Ti6Al4V-xTA15 powders,leading to varied performances.In conclusion,the mixed Ti6Al4V-70%TA15(x=70%)powders is the most suitable candidate and is recommended as the raw material for LAR of TA15 forgings based on overall consideration of the compatibility calculations of the laser repaired zone with the wrought substrate zone.展开更多
In this letter we consider a limit symmetry of the modified KdV equation and its application. The similarity reduction leads to limit solutions of the modified KdV equation. Besides, a modified KdV equation with new s...In this letter we consider a limit symmetry of the modified KdV equation and its application. The similarity reduction leads to limit solutions of the modified KdV equation. Besides, a modified KdV equation with new self-consistent sources is obtained and its solutions are derived.展开更多
We estimate the correction of relativistic center-of-mass vector on electric polarizability of an equal-mass quark-antiquark system numerically. Effect on the system confined by different interactive potentials is ana...We estimate the correction of relativistic center-of-mass vector on electric polarizability of an equal-mass quark-antiquark system numerically. Effect on the system confined by different interactive potentials is analysed. A great improvement for the electric polarizability of pion meson is obtained.展开更多
Hirschsprung's disease is a congenital disorder that occurs in 1:5000 live births. It is characterised by an absence of enteric neurons along a variable region of the gastrointestinal tract. Hirschsprung's dis...Hirschsprung's disease is a congenital disorder that occurs in 1:5000 live births. It is characterised by an absence of enteric neurons along a variable region of the gastrointestinal tract. Hirschsprung's disease is classified as a multigenic disorder, because the same phenotype is associated with mutations in multiple distinct genes. Furthermore, the genetics of Hirschsprung's disease are highly complex and not strictly Mendelian. The phenotypic variability and incomplete penetrance observed in Hirschsprung' s disease also suggests the involvement of modifier genes. Here, we summarise the current knowledge of the genetics underlying Hirschsprung's disease based on human and animal studies, focusing on the principal causative genes, their interactions, and the role of modif ier genes.展开更多
基金Project(2011AA030103) supported by the National High-tech Research Program of ChinaProject(201001C0104669453) supported by the Guangdong Innovation R&D Team Project,China
文摘Phospahting coated WE43 magnesium alloy was prepared by an immersion method. The microstructure, corrosion resistance and biocompatibility of the coated alloy were investigated. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to examine the microstructure and the composition of the coated alloy. The corrosion resistance was studied by means of potentiodynamic polarization method and the biocompatibility of the surface modified WE43 alloy was evaluated by (3-(4,5)-Dimethylthiazol-2, yl)-2,5-diphenyltetrazolium bromide (MTT) and hemolysis test. The results show that the phosphating coating can enhance the corrosion resistance of WE43 alloy and can be a good candidate to increase the biocompatibility of WE43 alloy.
基金Projects(11079022,51271093,10904071,U1332106)supported by the National Natural Science Foundation of China
文摘A set of stacked ribbons with the composition of Fe77Ga23 were prepared with different wheel velocities of 7 m/s, 12.5 m/s and 25 m/s(named as S7, S12.5 and S25, respectively). High resolution X-ray diffraction patterns of these ribbons show that all the ribbons present the disordered A2 structure, whereas an additional modified-DO3 phase is detected in S12.5 and S25. S25 has stronger(100) texture than other two samples. Ga K-edge extended X-ray absorption fine structure results indicate that both bond distance and the number of Ga atoms in the second neighbor shell around Ga decrease with increasing wheel velocity. No Ga cluster is detected in the studied ribbons. A short-range ordering Ga-rich phase and large local strain have no obvious influence on magnetostriction of S7. It is believed that both the(100) texture and the additional modified-DO3 phase play a positive role in magnetostrictive properties of Fe77Ga23 ribbons.
基金The National Natural Science Foundation of China(No.61273209)the Scientific Research Foundation of Graduate School of Southeast University(No.YBJJ1528)the Scientific Innovation Research of College Graduates in Jiangsu Province(No.KYLX15-0191)
文摘A semantics-based model is proposed to enable weakened hedges, such as "more or less" and "roughly" in the context of linguistic multi-criteria decision making. First, the resemblance relations are defined based on the semantics of terms on the domain. Then, the hedges can be represented after the upper and loose upper approximations of a linguistic term are derived. Accordingly, some compact formulae can be derived for the semantics of linguistic expressions with hedges. Parameters in these formulae are objectively determined according to the semantics of original terms. The proposed model presents a more natural way to express the decision information under uncertainties and its semantics is clear. The proposed model is clarified by solving the problem of evaluation and selection of sustainable innovative energy technologies. Computational results demonstrate that the model can deal with various uncertainties of the problem. Finally, the model is compared with existing techniques and extended to the case when the semantics of terms are represented by trapezoidal fuzzy numbers.
文摘This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantities of this system in equilibrium are obtained.
文摘To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and slenderspindle short shoot in Xingtang County of Hebai Province were investigated, then by SPSS anal- ysis, the correlations between the taperingness and each growth factor of inserted small branch were compared. The results showed that the taperingness of central trunk of free spindle dwarf-shoot Fuji apple treeshad negative correlations with each factor of inserted small branch, while the taperingness of central trunk of free spin- dle long-shoot Fuji apple treeshad positive correlations with each factor of inserted small branch, the taperingness of central trunk of slenderspindle short-shootFuji ap- ple treeshad negative correlation with total thickness of inserted small branch, but had positive correlations with other factors. This study can provide a scientifictheo- retical basis for the pruning technology of high-density planting trees grafting by dwarfing self-rooted rootstock.
文摘The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral correction technique (MSASC). The aggregation of AABB on CTAB followed the Langmuir isothermal adsorption law. The enrichment of AABB on CTAB sensitized the complexation between Cu(Ⅱ) or Ni(Ⅱ)and AABB. The binding ratio of AABB to CTAB was 1:2.5, and monomeric aggregate, AABB2CTAB5, was formed with an adsorption constant of 5.95×10^5 at 20 ℃ or 2.48×10^5 at 40 ℃. In the ternary complexation, the ratio of AABB:Cu and AABB:Ni were 1:1 and 1:2.5, respectively. Two types of aggregates, Cu2.AABB2·CTAB80 and Ni5.AABB2.CTAB80, were formed.
文摘We present an approach to solve Bethe-Salpeter (BS) equations exactly withoutany approximation if the kernel of the BS equations exactly is instantaneous, and take positroniumas an example to illustrate the general features of the exact solutions. The key step for theapproach is from the BS equations to derive a set of coupled and well-determined integrationequations in linear eigenvalue for the components of the BS wave functions equivalently, which maybe solvable numerically under a controlled accuracy, even though there is no analytic solution. Forpositronium, the exact solutions precisely present corrections to those of the correspondingSchrodinger equation in order υ~1 (υ is the relative velocity) for eigenfunctions, in order υ~2for eigenvalues, and the mixing between S and D components in J~(PC) = 1~(--) states etc.,quantitatively. Moreover, we also point out that there is a questionable step in some existentderivations for the instantaneous BS equations if one is pursuing the exact solutions. Finally, weemphasize that one should take the O(υ) corrections emerging in the exact solutions into accountaccordingly if one is interested in the relativistic corrections for relevant problems to the boundstates.
基金supported by the National Natural Science Foundation of China(No.51606081)the Basic Research Foundation of Shenzhen(No.JCYJ20160506170043770)
文摘In order to explore the influence of modification sites of functional groups on landfill gas (CO2/CH4) separation performance of metal-organic frameworks (MOFs), six types of or- ganic linkers and three types of functional groups (i.e. -F, -NH2, -CH3) were used to construct 36 MOFs of pcu topology based on copper paddlewheel. Grand canonical Monte Carlo sim- ulations were performed in this work to evaluate the separation performance of MOFs at low (vacuum swing adsorption) and high (pressure swing adsorption) pressures, respectively. Simulation results demonstrated that CO2 working capacity of the unfunctionalized MOFs generally exhibits pore-size dependence at 1 bar, which increases with the decrease in pore sizes. It was also found that -NH2 funetionalized MOFs exhibit the highest CO2 uptake due to the enhanced Coulombic interactions between the polar -NH2 groups and the quadrupole moment of CO2 molecules, which is followed by -CH3 and -F functionalized ones. Moreover, positioning the functional groups -NH2 and -CH3 at sites far from the metal node (site b) exhibits more significant enhancement on CO2/CH4 separation performance compared to that adjacent to the metal node (site a).
基金supported by the National Natural Science Foundation of China (21771070, 21571071)the Fundamental Research Funds for the Central Universities (2018KFYYXJJ120, 2019KFYRCPY104)~~
文摘In this study,an acid-induced assembly strategy for a rutile TiO2 photocatalyst was proposed on the basis of the treatment of lamellar protonated titanate with a concentrated HNO3 solution.Nitrate groups were successfully grafted onto a TiO2 surface and induced the assembly of rutile TiO2 nanorods into uniform spindle-like nanobundles.The resulting TiO2 product achieved a photocatalytic hydrogen evolution rate of 402.4μmol h^?1,which is 3.1 times higher than that of Degussa P25-TiO2.It was demonstrated that nitrate group grafting caused the rutile TiO2 surface to become negatively charged,which is favorable for trapping positive protons and improving charge carrier separation,thereby enhancing photocatalytic hydrogen production.Additionally,surface charges were crucial to structural stability based on electrostatic repulsion.This study not only developed a facile surface modification strategy for fabricating efficient H2 production photocatalysts but also identified an influence mechanism of inorganic acids different from that reported in the literature.
文摘Permacol mesh has shown promise when used in abdominal wall repair,especially in the presence of a contaminated surgical field.This biomaterial,derived from porcine dermis collagen,has proposed advantages over synthetic materials due to increased biocompatibility and reduced foreign body reaction within human tissues.However,we present a case report describing a patient who displayed rejection to a Permacol mesh when used in the repair of abdominal wound dehiscence following an emergency laparotomy.Review of the English language literature using PubMed and Medline, showed only two previously published cases of explantation of Permacoldue to sepsis or wound breakdown. The authors believe this is the first case of severe foreign body reaction leading to rejection of Permacol.Both animal and human studies show conflicting evidence of biocompatibility.There are several reports of successful use of Permacolto repair complex incisional herniae or abdominal walls in the presence of significant contamination.It appears from the literature that Permacolis a promising material,but as we have demonstrated,it has the potential to evoke a foreign body reaction and rejection in certain subjects.
基金Supported by the National Natural Science Foundation of China (20736002), the National High Technology Research and Development Program of China (2008AA062302) and Program for Changjiang Scholars and Innovative Research Team in University of China (IRT0721).
文摘Covalent organic framework (COF) is a porous material with low density and large BET (Brtmauer-Emmett-Teller) surface area. They have great potential in gas adsorption and separation. In this work, the adsorption of pure CO2 and CO2/CH4 mixture on modified COF-102 was simulated by using GCMC (grand canonical Monte Carlo). Metal Li was incorporated into COF-102 through three doping methods, including charge exchange, O^--Li6+ dipolar interaction and O^--Li^+ chemical bonding. The influence of Li doping on the adsorption of CO2 was studied. The results showed that among the three methods, the dipole doping is the best way to improve CO2 adsorption performance. Further, the ligands of COF-102 were replaced by extended aromatic moieties, such as diphenyl and pyrene. The adsorption capacity of CO2 and CH4, and the selectivity of CO2/CH4 on the ligand-replaced COF-102 were studied. The capacity of CO2 and CH4 on the ligand-replaced COF-102 had obvious changes; hence the selectivity of CO2/CH4 can be adjusted accordingly.
文摘Phase diverse speckle is a novel kind of imaging technique and can be used to overcome image degradation from unknown phase aberrations, such as atmospheric turbulence. The wave-front phase expanded on the Zernike polynomials is esti- mated from a pair of images (in the focal and out of focus planes). In this paper the principle of PDS is analyzed, and genetic algorithm is used as the iterative algorithm to simulate some characteristics, such as the influence of Zernike polynomials’ mode, amplitude of turbulence on the phase estimation. Thus, a new method for recovery of images is explored.
基金Project(51364035) supported by the National Natural Science Foundation of China Project(20133601110001) supported by the Ministry of Education Tied up with the Special Research Fund for the Doctoral Program for Higher School, China+1 种基金 Project(KJLD14003) supported by the Loading Program of Science and Technology of College of Jiangxi Province, China Project(2012-CYH-DW-XCL-002) supported by the Production and Teaching and Research Cooperation Plan of Naaachaaag Non-party Experts and Doctor, China
文摘The effects of heat treatment and strontium (SO addition on the microstructure and mechanical properties of ADC12 alloys were investigated, and two-stage solution treatment was introduced. The results indicated that the addition of Sr obviously refined the microstructure of ADC12 alloys. When 0.05 wt% Sr was added into the alloy, the eutectic Si phase was fully modified into fine fibrous structure; a-A1 and fl-A15FeSi phases were best refined; and the eutectic AlzCu phase was modified into block-like AlzCu phase that continuously distributed at the grain boundary. The ultimate tensile strength (UTS) (270.63 MPa) and elongation (3.19%) were increased by 51.2% and 73.4% respectively compared with unmodified alloys. After the two-stage solution treatment (500 ~C, 6 h+520 ~C, 4 h), for 0.05 wt% Sr modified ADC12 alloys, the Si phases transformed into fine particle structure and AlzCu phases were fully dissolved. The peak hardness value of the alloys processed by the two-stage solution treatment was increased by 8.3% and 6.8% respectively compared to solution treatment at 500 ~C and 520 ~C. After the aging treatment (175 ~C, 7 h), the hardness and UTS were increased by 38.73% and 13.96% respectively when compared with the unmodified alloy.
文摘Heterogeneous photocatalysis,an advanced oxidation process,has garnered extensive attention in the field of environmental remediation because it involves the direct utilization of solar energy for the removal of numerous pollutants.However,the application of heterogeneous photocatalysis in environmental remediation has not achieved the expected consequences due to enormous challenges such as low photocatalytic efficiencies and high costs of heterogeneous photocatalysts in large-scale practical applications.Furthermore,pollutants in the natural environment,including water,air,and solid phases,are diverse and complex.Therefore,extensive efforts should be made to better understand and apply heterogeneous photocatalysis for environmental remediation.Herein,the fundamentals of heterogeneous photocatalysis for environmental remediation are introduced.Then,potential semiconductors and their modification strategies for environmental photocatalysis are systematically presented.Finally,conclusions and prospects are briefly summarized,and the direction for the future development of environmental photocatalysis is explored.This review may provide reference directions toward understanding,researching,and designing photocatalytic remediation systems for various environmental pollutants.
基金Supported by the Science Fund for Young Scholars of Southwest University under Grant No.SWU208035 Fundamental Research Funds of Central University under Grant No.XDJK2009C020
文摘The multi-configuration Dirac-Fock method is used in this work to calculate ground-state ionization potentials of Boron and Carbon isoelectronic sequences from Z = 6 to Z=42. And the contribution of relativistic corrections, nuclear volume effect, Breit and QED effects to tile results is discussed in the calculation. The results are compared with the scanty existing theoretical and experimental data in the literature and good agreements are achieved. Then analytical expressions of lonization potential along Boron and Carbon isoelectronic sequences are obtained.
基金Project(2019-00899-1-1)supported by the Ministry of Industry and Information Technology of ChinaProject(2021JM-060)supported by the Natural Science Foundation of Shaanxi Province,ChinaProject(3102019QD0409)supported by the Fundamental Research Funds for the Central Universities,China。
文摘The application of mixed powders with different mass fraction on laser additive repairing(LAR)can be an effective way to guarantee the performance and functionality of repaired part in time.A convenient and feasible approach is presented to repair TA15 forgings by employing Ti6Al4V-xTA15 mixed powders in this paper.The performance compatibility of Ti6Al4V-xTA15 powders from the aspects of microhardness,tensile property,heat capacity,thermal expansion coefficient and corrosion resistance with the TA15 forgings was fully investigated.The primaryαlaths were refined and the volume fraction of the secondaryαphase was increased by increasing the mass fraction of TA15 in the mixed Ti6Al4V-xTA15 powders,leading to varied performances.In conclusion,the mixed Ti6Al4V-70%TA15(x=70%)powders is the most suitable candidate and is recommended as the raw material for LAR of TA15 forgings based on overall consideration of the compatibility calculations of the laser repaired zone with the wrought substrate zone.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10871165 and 10926036the Education Department under Grant No.Y200906909the Natural Science Foundation of under Grant No.Y6100126 of Zhejiang Province
文摘In this letter we consider a limit symmetry of the modified KdV equation and its application. The similarity reduction leads to limit solutions of the modified KdV equation. Besides, a modified KdV equation with new self-consistent sources is obtained and its solutions are derived.
基金国家自然科学基金,the Institute of Theoretical Physics,中国科学院知识创新工程项目
文摘We estimate the correction of relativistic center-of-mass vector on electric polarizability of an equal-mass quark-antiquark system numerically. Effect on the system confined by different interactive potentials is analysed. A great improvement for the electric polarizability of pion meson is obtained.
基金Supported by The National Health and Medical Research Council of Australia to Anderson RB: Project grant, No. 509219a CDA Fellowship, No. 454773
文摘Hirschsprung's disease is a congenital disorder that occurs in 1:5000 live births. It is characterised by an absence of enteric neurons along a variable region of the gastrointestinal tract. Hirschsprung's disease is classified as a multigenic disorder, because the same phenotype is associated with mutations in multiple distinct genes. Furthermore, the genetics of Hirschsprung's disease are highly complex and not strictly Mendelian. The phenotypic variability and incomplete penetrance observed in Hirschsprung' s disease also suggests the involvement of modifier genes. Here, we summarise the current knowledge of the genetics underlying Hirschsprung's disease based on human and animal studies, focusing on the principal causative genes, their interactions, and the role of modif ier genes.