Collisions between hot H atoms and CO2 molecules were studied experimentally by time resolved Fourier transform infrared emission spectroscopy. H atoms with three translational energies, 174.7, 241.0 and 306.2 k J/mol...Collisions between hot H atoms and CO2 molecules were studied experimentally by time resolved Fourier transform infrared emission spectroscopy. H atoms with three translational energies, 174.7, 241.0 and 306.2 k J/mol respectively, were generated by UV laser photolysis to initiate a chemical reaction of H＋CO2→OH＋CO. Vibrationally excited CO （v≤2） was observed in the spectrum, where CO was the product of the reaction. The highly efficient T-V energy transfer fro,n the hot H atoms to the CO2 was verified too. The highest vibrational level of v=4 in CO2 （va） was found. Rate ratio of the chemical reaction to the energy transfer was estimated as 10.展开更多
Aluminum-matrix boron carbide (B4Cp/Al) is a kind of neutron absorbing material widely used in nuclear spent fuel storage. In order to improve the tensile property of B4Cp/Al composites, a new type of nano-Al2O3 parti...Aluminum-matrix boron carbide (B4Cp/Al) is a kind of neutron absorbing material widely used in nuclear spent fuel storage. In order to improve the tensile property of B4Cp/Al composites, a new type of nano-Al2O3 particle (Al2O3np) reinforced B4Cp/Al + Al2O3np composites were prepared by powder metallurgy method. The Monte Carlo particle transport program (MCNP) was used to determine the influence of Al2O3np on the thermal neutron absorptivity of composites. The universal material testing machine and scanning electron microscope (SEM) were used to study the mechanical properties, microstructure and fracture morphology of B4Cp/Al composites. The results indicated that the neutron absorption properties of B4Cp/Al composites were not affected by the addition of nano-Al2O3 particles in the range of 1 wt%-15 wt%. The addition of Al2O3np can obviously reduce the grain size of B4Cp/Al matrix metals thus improve the tensile strength of the composites. The addition threshold of Al2O3np is about 2.5 wt%. Both B4Cp and Al2O3np change the fracture characteristics of the composites from toughness to brittleness, and the latter is more important.展开更多
α-diketones and β-diketones react with Grignard reagents in the presence of a catalytic amount of Cp2TiCl2 to yield a-ketols and corresponding ketones respectively. Sulfoxides can be deoxygenated by Cp2TiCl2/Al syst...α-diketones and β-diketones react with Grignard reagents in the presence of a catalytic amount of Cp2TiCl2 to yield a-ketols and corresponding ketones respectively. Sulfoxides can be deoxygenated by Cp2TiCl2/Al system. The possible mechanisms are also discussed.展开更多
Soliton molecules(SMs)of the(2+1)-dimensional generalized KonopelchenkoDubrovsky-Kaup-Kupershmidt(gKDKK)equation are found by utilizing a velocity resonance ansatz to N-soliton solutions,which can transform to asymmet...Soliton molecules(SMs)of the(2+1)-dimensional generalized KonopelchenkoDubrovsky-Kaup-Kupershmidt(gKDKK)equation are found by utilizing a velocity resonance ansatz to N-soliton solutions,which can transform to asymmetric solitons upon assigning appropriate values to some parameters.Furthermore,a double-peaked lump solution can be constructed with breather degeneration approach.By applying a mixed technique of a resonance ansatz and conjugate complexes of partial parameters to multisoliton solutions,various kinds of interactional structures are constructed;There include the soliton molecule(SM),the breather molecule(BM)and the soliton-breather molecule(SBM).Graphical investigation and theoretical analysis show that the interactions composed of SM,BM and SBM are inelastic.展开更多
Objective： To explore the roles of the expression of the co-stimulatory molecule, B7-2, and the co-inhibitory molecule, PD-L1, on peripheral blood mononuclear cells in the mechanism of immunotolerance in chronic hepa...Objective： To explore the roles of the expression of the co-stimulatory molecule, B7-2, and the co-inhibitory molecule, PD-L1, on peripheral blood mononuclear cells in the mechanism of immunotolerance in chronic hepatitis B virus infection. Methods： Thirty HBV infected patients in the immunoreactive phase and 20 patients in the immunotolerant phase were enrolled in the study, while 20 healthy volunteers were used as controls. RT- PCR and real-time PCR methods were used to detect the expression levels of B7-2 and PD-L1 mRNA in peripheral blood mononuclear cells in chronic HBV infected patients. Results： The B7-2 expression in irnrnunoreactive and immunotolerant patients was significantly lower than that in the controls （P all 〈 0.01 ）; B7-2 expression in immunoreactive patients was significantly lower than in immunotolerant patients （P 〈 0.01）. PD-L1 expression in irnmunoreactive patients and immunotolerant patients was significantly higher than that in normal controls （P all 〈 0.01）. The PD-L1/BT-2 ratios in immunoreactive and immunotolerant patients were significantly higher than that of the healthy controls （P all 〈 0.01）; the PD-L1/ B7-2 ratio was significantly higher in the immunoreactive patients than in the immunotolerant patients （P 〈 0.01）. Conclusion： In chronic HBV infection, changes in the expression of co-stimulatory and co-inhibitory molecules imply a protective adjustment against the patient＇ s immune response that may result in increased immunotolerance and persistent HBV infection.展开更多
Cp;ZrCl（S;CNBz;） is a five-coordinate bent zirconocene in which the dibenzyldithiocarbamate is a bidentate ligand (Zr-Cl 2.549（1）A; Zr-C 2.489-2.533; Zr-S 2.667（1）, 2.734（1）; Zr-Cl-S1 137.6（1）;; Zr-Cl-S2 73....Cp;ZrCl（S;CNBz;） is a five-coordinate bent zirconocene in which the dibenzyldithiocarbamate is a bidentate ligand (Zr-Cl 2.549（1）A; Zr-C 2.489-2.533; Zr-S 2.667（1）, 2.734（1）; Zr-Cl-S1 137.6（1）;; Zr-Cl-S2 73.3（1）;).展开更多
Three new isomers of FCH2CP system, F(H)CCPH (1), F-cCPC-H(H) (2) and F-cCC(H)P-H (3), are predicted by means of B3LYP and CCSD(T) (single-point) methods with 6-311++G(d,p) and 6-311++G(2df,2p) basis sets, respectivel...Three new isomers of FCH2CP system, F(H)CCPH (1), F-cCPC-H(H) (2) and F-cCC(H)P-H (3), are predicted by means of B3LYP and CCSD(T) (single-point) methods with 6-311++G(d,p) and 6-311++G(2df,2p) basis sets, respectively. The three calculated isomers can isomerize into thermodynamically the most stable species F-cPC(H)C-H, which has been suggested in previous theoretical studies, with relatively higher reaction barriers. In view of their higher thermodynamic and kinetic stability, we believe that the three species can be detected in future experiments.展开更多
We report the anatase titanium dioxide （101） surface adsorption of sp3-hybridized gas molecules, including NH3, 1-12 0 and CH4, using first-principles plane-wave ultrasoft pseudopotential based on the density functi...We report the anatase titanium dioxide （101） surface adsorption of sp3-hybridized gas molecules, including NH3, 1-12 0 and CH4, using first-principles plane-wave ultrasoft pseudopotential based on the density functional theory. The results show that it is much easier for a surface with oxygen vacancies to adsorb gas molecules than it is for a surface without oxygen vacancies. The main factor affecting adsorption stability and energy is the polarizability of molecules, and adsorption is induced by surface oxygen vacancies of the negatively charged center. The analyses of state densities and charge population show that charge transfer occurs at the molecule surface upon adsorption and that the number of transferred charge reduces in the order of N, 0 and C. Moreover, the adsorption method is chemical adsorption, and adsorption stability decreases in the order of NH3, tt2 0 and CH4. Analyses of absorption and reflectance spectra reveal that after absorbed CH4 and H2 O, compared with the surface with oxygen vacancy, the optical properties of materials surface, including its absorption coefficients and reflectivity index, have slight changes, however, absorption coefficient and reflectivity would greatly increase after NH3 adsorption. These findings illustrate that anatase titanium dioxide （101） surface is extremely sensitive to NH3.展开更多
The(2+1)-dimensional elliptic Toda equation is a high-dimensional generalization of the Toda lattice and a semidiscrete Kadomtsev–Petviashvili I equation.This paper focuses on investigating the resonant interactions ...The(2+1)-dimensional elliptic Toda equation is a high-dimensional generalization of the Toda lattice and a semidiscrete Kadomtsev–Petviashvili I equation.This paper focuses on investigating the resonant interactions between two breathers,a breather/lump and line solitons as well as lump molecules for the(2+1)-dimensional elliptic Toda equation.Based on the N-soliton solution,we obtain the hybrid solutions consisting of line solitons,breathers and lumps.Through the asymptotic analysis of these hybrid solutions,we derive the phase shifts of the breather,lump and line solitons before and after the interaction between a breather/lump and line solitons.By making the phase shifts infinite,we obtain the resonant solution of two breathers and the resonant solutions of a breather/lump and line solitons.Through the asymptotic analysis of these resonant solutions,we demonstrate that the resonant interactions exhibit the fusion,fission,time-localized breather and rogue lump phenomena.Utilizing the velocity resonance method,we obtain lump–soliton,lump–breather,lump–soliton–breather and lump–breather–breather molecules.The above works have not been reported in the(2+1)-dimensional discrete nonlinear wave equations.展开更多
We perform a kinetically complete measurement on the fragmentation of Coulomb explosion of 1-120 molecules in intense few-cycle linearly and circularly polarized laser fields. Both the fragmentations of 1t203＋ and H...We perform a kinetically complete measurement on the fragmentation of Coulomb explosion of 1-120 molecules in intense few-cycle linearly and circularly polarized laser fields. Both the fragmentations of 1t203＋ and H204＋ reveal the concerted pathway of dissociation. The length of the OH bond prior to the Coulomb explosion of both molecular ions is sensitive to the laser pulse duration and laser intensity. However, the bending angle of H-O-H is less sensitive to the pulse duration and laser intensity. We introduce the mechanism of charge resonance enhanced double ionization to elucidate the triple （or quadruple） dissociative ionization dynamics of H20, in which two electrons are non-adiabatically localized at the protons of the precursor ion H2O^＋ （or H2O^2＋） and are released simultaneously due to the over barrier ionization in the combined laser field and molecular ionic potential. Such charge resonance enhanced multiple ionization is not suppressed in few-cycle laser fields and elliptically polarized laser fields.展开更多
Objective: To investigate the correlation of Runt-related transcription factor 2 (RunX2) with proliferation genes, tumor suppressor genes and angiogenesis molecules in colon cancer lesions. Methods: A total of 90 pati...Objective: To investigate the correlation of Runt-related transcription factor 2 (RunX2) with proliferation genes, tumor suppressor genes and angiogenesis molecules in colon cancer lesions. Methods: A total of 90 patients with primary colon cancer were enrolled in colon cancer group, 68 patients with benign colon polyps were enrolled in colon polyps group, the differences in the expression levels of RunX2, proliferation genes, tumor suppressor genes and angiogenesis molecules in the two groups of lesions were compared, and Pearson test was further used to evaluate the correlation of RunX2 expression level with proliferation gene, tumor suppressor gene and angiogenesis molecule expression levels in colon cancer tissues. Results: RunX2 mRNA expression level in the lesions of colon cancer group was higher than that of colon polyps group. Proliferation genes GTPBP4, HOXB7, ZNF331, ADAM17 and HSP60 mRNA expression levels in the lesions of colon cancer group were higher than those of colon polyps group;tumor suppressor genes ATF3, FOXN3, OTUD1 and NDRG2 mRNA expression levels were lower than those of colon polyps group;angiogenesis molecules Musashi 1, NF-κB, RegⅣ and STAT3 mRNA expression levels were higher than those of colon polyps group. RunX2 mRNA expression level in the colon cancer lesions was directly correlated with the expression levels of the above proliferation genes, tumor suppressor genes and angiogenesis molecules. Conclusion: RunX2 expression is abnormally high in colon cancer lesions, the specific expression level is positively correlated with cancer cell proliferation activity and angiogenesis activity, and it is an important molecular target that can lead to the occurrence and development of colon cancer.展开更多
基金supported by the National Natural Science Foundation of China and the National Basic Research Program of China(973 Program).
文摘Collisions between hot H atoms and CO2 molecules were studied experimentally by time resolved Fourier transform infrared emission spectroscopy. H atoms with three translational energies, 174.7, 241.0 and 306.2 k J/mol respectively, were generated by UV laser photolysis to initiate a chemical reaction of H＋CO2→OH＋CO. Vibrationally excited CO （v≤2） was observed in the spectrum, where CO was the product of the reaction. The highly efficient T-V energy transfer fro,n the hot H atoms to the CO2 was verified too. The highest vibrational level of v=4 in CO2 （va） was found. Rate ratio of the chemical reaction to the energy transfer was estimated as 10.
基金Funded by Natural National Science Foundation of China(NSFC)(No.11305149)National High-Tech R&D Program(863 Program)(No.2013AA030704)。
文摘Aluminum-matrix boron carbide (B4Cp/Al) is a kind of neutron absorbing material widely used in nuclear spent fuel storage. In order to improve the tensile property of B4Cp/Al composites, a new type of nano-Al2O3 particle (Al2O3np) reinforced B4Cp/Al + Al2O3np composites were prepared by powder metallurgy method. The Monte Carlo particle transport program (MCNP) was used to determine the influence of Al2O3np on the thermal neutron absorptivity of composites. The universal material testing machine and scanning electron microscope (SEM) were used to study the mechanical properties, microstructure and fracture morphology of B4Cp/Al composites. The results indicated that the neutron absorption properties of B4Cp/Al composites were not affected by the addition of nano-Al2O3 particles in the range of 1 wt%-15 wt%. The addition of Al2O3np can obviously reduce the grain size of B4Cp/Al matrix metals thus improve the tensile strength of the composites. The addition threshold of Al2O3np is about 2.5 wt%. Both B4Cp and Al2O3np change the fracture characteristics of the composites from toughness to brittleness, and the latter is more important.
基金Project (No. 20072033) supported by the National Natural Science Foundation of China and the Specialized Research Fund for the Doctoral Program of Higher Education Ministry, China
文摘α-diketones and β-diketones react with Grignard reagents in the presence of a catalytic amount of Cp2TiCl2 to yield a-ketols and corresponding ketones respectively. Sulfoxides can be deoxygenated by Cp2TiCl2/Al system. The possible mechanisms are also discussed.
基金Supported by the National Natural Science Foundation of China(12001424)the Natural Science Basic Research Program of Shaanxi Province(2021JZ-21)the Fundamental Research Funds for the Central Universities(2020CBLY013)。
文摘Soliton molecules(SMs)of the(2+1)-dimensional generalized KonopelchenkoDubrovsky-Kaup-Kupershmidt(gKDKK)equation are found by utilizing a velocity resonance ansatz to N-soliton solutions,which can transform to asymmetric solitons upon assigning appropriate values to some parameters.Furthermore,a double-peaked lump solution can be constructed with breather degeneration approach.By applying a mixed technique of a resonance ansatz and conjugate complexes of partial parameters to multisoliton solutions,various kinds of interactional structures are constructed;There include the soliton molecule(SM),the breather molecule(BM)and the soliton-breather molecule(SBM).Graphical investigation and theoretical analysis show that the interactions composed of SM,BM and SBM are inelastic.
文摘Objective： To explore the roles of the expression of the co-stimulatory molecule, B7-2, and the co-inhibitory molecule, PD-L1, on peripheral blood mononuclear cells in the mechanism of immunotolerance in chronic hepatitis B virus infection. Methods： Thirty HBV infected patients in the immunoreactive phase and 20 patients in the immunotolerant phase were enrolled in the study, while 20 healthy volunteers were used as controls. RT- PCR and real-time PCR methods were used to detect the expression levels of B7-2 and PD-L1 mRNA in peripheral blood mononuclear cells in chronic HBV infected patients. Results： The B7-2 expression in irnrnunoreactive and immunotolerant patients was significantly lower than that in the controls （P all 〈 0.01 ）; B7-2 expression in immunoreactive patients was significantly lower than in immunotolerant patients （P 〈 0.01）. PD-L1 expression in irnmunoreactive patients and immunotolerant patients was significantly higher than that in normal controls （P all 〈 0.01）. The PD-L1/BT-2 ratios in immunoreactive and immunotolerant patients were significantly higher than that of the healthy controls （P all 〈 0.01）; the PD-L1/ B7-2 ratio was significantly higher in the immunoreactive patients than in the immunotolerant patients （P 〈 0.01）. Conclusion： In chronic HBV infection, changes in the expression of co-stimulatory and co-inhibitory molecules imply a protective adjustment against the patient＇ s immune response that may result in increased immunotolerance and persistent HBV infection.
文摘Cp;ZrCl（S;CNBz;） is a five-coordinate bent zirconocene in which the dibenzyldithiocarbamate is a bidentate ligand (Zr-Cl 2.549（1）A; Zr-C 2.489-2.533; Zr-S 2.667（1）, 2.734（1）; Zr-Cl-S1 137.6（1）;; Zr-Cl-S2 73.3（1）;).
文摘Three new isomers of FCH2CP system, F(H)CCPH (1), F-cCPC-H(H) (2) and F-cCC(H)P-H (3), are predicted by means of B3LYP and CCSD(T) (single-point) methods with 6-311++G(d,p) and 6-311++G(2df,2p) basis sets, respectively. The three calculated isomers can isomerize into thermodynamically the most stable species F-cPC(H)C-H, which has been suggested in previous theoretical studies, with relatively higher reaction barriers. In view of their higher thermodynamic and kinetic stability, we believe that the three species can be detected in future experiments.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61274128 and 61106129the Natural Science Foundation of Chongqing under Grant No CSTC2013JCYJA0731the Scientific Talent Training Foundation of Chongqing under Grant No CSTC2013KJRC-QNRC0080
文摘We report the anatase titanium dioxide （101） surface adsorption of sp3-hybridized gas molecules, including NH3, 1-12 0 and CH4, using first-principles plane-wave ultrasoft pseudopotential based on the density functional theory. The results show that it is much easier for a surface with oxygen vacancies to adsorb gas molecules than it is for a surface without oxygen vacancies. The main factor affecting adsorption stability and energy is the polarizability of molecules, and adsorption is induced by surface oxygen vacancies of the negatively charged center. The analyses of state densities and charge population show that charge transfer occurs at the molecule surface upon adsorption and that the number of transferred charge reduces in the order of N, 0 and C. Moreover, the adsorption method is chemical adsorption, and adsorption stability decreases in the order of NH3, tt2 0 and CH4. Analyses of absorption and reflectance spectra reveal that after absorbed CH4 and H2 O, compared with the surface with oxygen vacancy, the optical properties of materials surface, including its absorption coefficients and reflectivity index, have slight changes, however, absorption coefficient and reflectivity would greatly increase after NH3 adsorption. These findings illustrate that anatase titanium dioxide （101） surface is extremely sensitive to NH3.
基金the National Natural Science Foundation of China(Grant Nos.12061051 and 11965014)。
文摘The(2+1)-dimensional elliptic Toda equation is a high-dimensional generalization of the Toda lattice and a semidiscrete Kadomtsev–Petviashvili I equation.This paper focuses on investigating the resonant interactions between two breathers,a breather/lump and line solitons as well as lump molecules for the(2+1)-dimensional elliptic Toda equation.Based on the N-soliton solution,we obtain the hybrid solutions consisting of line solitons,breathers and lumps.Through the asymptotic analysis of these hybrid solutions,we derive the phase shifts of the breather,lump and line solitons before and after the interaction between a breather/lump and line solitons.By making the phase shifts infinite,we obtain the resonant solution of two breathers and the resonant solutions of a breather/lump and line solitons.Through the asymptotic analysis of these resonant solutions,we demonstrate that the resonant interactions exhibit the fusion,fission,time-localized breather and rogue lump phenomena.Utilizing the velocity resonance method,we obtain lump–soliton,lump–breather,lump–soliton–breather and lump–breather–breather molecules.The above works have not been reported in the(2+1)-dimensional discrete nonlinear wave equations.
基金Supported by the National Basic Research Program of China under Grant No 2013CB922403the National Natural Science Foundation of China under Grant Nos 11125416,11434002,11121091 and 11134001
文摘We perform a kinetically complete measurement on the fragmentation of Coulomb explosion of 1-120 molecules in intense few-cycle linearly and circularly polarized laser fields. Both the fragmentations of 1t203＋ and H204＋ reveal the concerted pathway of dissociation. The length of the OH bond prior to the Coulomb explosion of both molecular ions is sensitive to the laser pulse duration and laser intensity. However, the bending angle of H-O-H is less sensitive to the pulse duration and laser intensity. We introduce the mechanism of charge resonance enhanced double ionization to elucidate the triple （or quadruple） dissociative ionization dynamics of H20, in which two electrons are non-adiabatically localized at the protons of the precursor ion H2O^＋ （or H2O^2＋） and are released simultaneously due to the over barrier ionization in the combined laser field and molecular ionic potential. Such charge resonance enhanced multiple ionization is not suppressed in few-cycle laser fields and elliptically polarized laser fields.
文摘Objective: To investigate the correlation of Runt-related transcription factor 2 (RunX2) with proliferation genes, tumor suppressor genes and angiogenesis molecules in colon cancer lesions. Methods: A total of 90 patients with primary colon cancer were enrolled in colon cancer group, 68 patients with benign colon polyps were enrolled in colon polyps group, the differences in the expression levels of RunX2, proliferation genes, tumor suppressor genes and angiogenesis molecules in the two groups of lesions were compared, and Pearson test was further used to evaluate the correlation of RunX2 expression level with proliferation gene, tumor suppressor gene and angiogenesis molecule expression levels in colon cancer tissues. Results: RunX2 mRNA expression level in the lesions of colon cancer group was higher than that of colon polyps group. Proliferation genes GTPBP4, HOXB7, ZNF331, ADAM17 and HSP60 mRNA expression levels in the lesions of colon cancer group were higher than those of colon polyps group;tumor suppressor genes ATF3, FOXN3, OTUD1 and NDRG2 mRNA expression levels were lower than those of colon polyps group;angiogenesis molecules Musashi 1, NF-κB, RegⅣ and STAT3 mRNA expression levels were higher than those of colon polyps group. RunX2 mRNA expression level in the colon cancer lesions was directly correlated with the expression levels of the above proliferation genes, tumor suppressor genes and angiogenesis molecules. Conclusion: RunX2 expression is abnormally high in colon cancer lesions, the specific expression level is positively correlated with cancer cell proliferation activity and angiogenesis activity, and it is an important molecular target that can lead to the occurrence and development of colon cancer.
