Suspensions of a latosol with a clay concentration of 30 g kg^(-1) wereprepared from electrodialyzed clay fractions, less than 2 μm in diameter, five nitrate solutionswith a concentration of 1 X 10^(04)/z mol L^(-1),...Suspensions of a latosol with a clay concentration of 30 g kg^(-1) wereprepared from electrodialyzed clay fractions, less than 2 μm in diameter, five nitrate solutionswith a concentration of 1 X 10^(04)/z mol L^(-1), where z is the valence, and five sodium saltsolutions with a concentration of 3.3 X 10^(-5)/2 mol L^(-1). The direct current (DC) electricalconductivities (ECs) of the colloidal suspensions were measured at a constant temperature of 25 ℃,using a newly established method of measuring the Wien effect in soil suspensions at field strengthsranging from 13.5 to 150 kV cm^(-1), to determine their electrical conductivity-field strengthrelationships and to infer the order of the bonding strength (retaining force) between soilparticles and various ions. The measurements with the latosol suspensions in NaNO_3, KNO_3,Ca(NO_3)_2, Mg(NO_3)_2 and Zn(NO_3)_2 solutions resulted in increments of the suspension ECs, ΔECs,of 7.9, 5.0, 7.1, 7.0 and 5.8 μS cm^(-1), respectively, when the applied field strength increasedfrom 14.5 to 142 kV cm^(-1). As for the suspensions in NaNO_3, NaCl, Na_2SO_4, Na_3PO_4 andNa_3AsO_4 solutions, the ΔECs were 6.2, 5.3, 4.1, 4.0 and 3.7μS cm^(-1), respectively, when theapplied field strength increased from 13.5 to 90 kV cm^(-1). Thus, it can be deduced that theretaining forces of the clay fraction of the latosol for the cations were in the descending orderK^+ > Zn^(2+) > Mg^(2+) ≥ Ca^(2+) > Na^+, and for the anions in the descending order H_2AsO_4^- >H_2PO_4^-≥ SO_4^(2-) > Cl^- > NO_3~ -.展开更多
In the effective-mass approximation, using a simple two-parameter wave function and a one-dimensional (ID) equivalent potential model, we calculate variationally the binding energy of an exciton bound to a neutral d...In the effective-mass approximation, using a simple two-parameter wave function and a one-dimensional (ID) equivalent potential model, we calculate variationally the binding energy of an exciton bound to a neutral donor (D^0, X) in finite GaAs-AIxGa1-xAs quantum well wires (QWWs). At the wire width of 25 A, the binding energy has a peak value, which is also at the position of the peak of the exciton binding energy, and the center-of-mass wave functions of excitons reaches the most centralized distribution. In addition, the changing tendency of the average interparticle distance as the wire width is reverse to that of the binding energy.展开更多
Simultaneous effects of conduction band non-parabolicity and hydrostatic pressure on the binding energies of 1S, 2S, and 2P states along with diamagnetic susceptibility of an on-center hydrogenic impurity confined in ...Simultaneous effects of conduction band non-parabolicity and hydrostatic pressure on the binding energies of 1S, 2S, and 2P states along with diamagnetic susceptibility of an on-center hydrogenic impurity confined in typical GaAs/Alx- Ga1-x As spherical quantum dots are theoretically investigated using the matrix diagonalization method. In this regard, the effect of band non-parabolieity has been performed using the Luttinger-Kohn effective mass equation. The binding energies and the diamagnetic susceptibility of the hydrogenic impurity are computed as a function of the dot radius and different values of the pressure in the presence of conduction band non-parabolicity effect. The results we arrived at are as follows: the incorporation of the band edge non-parabolicity increases the binding energies and decreases the absolute value of the diamagnetic susceptibility for a given pressure and radius; the binding energies increase and the magnitude of the diamagnetic susceptibility reduces with increasing pressure.展开更多
Kondo transport properties through a Kondo-type quantum dot (QD) with a side-coupled triple-QD structure are systematically investigated by using the non-equilibrium Green's function method. We firstly derive the f...Kondo transport properties through a Kondo-type quantum dot (QD) with a side-coupled triple-QD structure are systematically investigated by using the non-equilibrium Green's function method. We firstly derive the formulae of the current, the linear conductance, the transmission coefficient, and the local density of states. Then we carry out the analytical and numerical studies and some universal conductance properties are obtained. It is shown that the number of the conductance valleys is intrinsically determined by the side-coupled QDs and at most equal to the number of the QDs included in the side-coupled structure in the asymmetric limit. In the process of forming the conductance valleys, the side-coupled QD system plays the dominant role while the couplings between the Kondo-type QD and the side-coupled structure play the subsidiary and indispensable roles. To testify the validity of the universal conductance properties, another different kinds of side-coupled triple-QD structures are considered. It should be emphasized that these universal properties axe applicable in understanding this kind of systems with arbitrary many-QD side structures.展开更多
In [1], Shen Guangyu constructed several classes of new simple Lie algebras of characteristic 2, which are called the variations of G2. In this paper, the authors investigate their derivation algebras. It is shown tha...In [1], Shen Guangyu constructed several classes of new simple Lie algebras of characteristic 2, which are called the variations of G2. In this paper, the authors investigate their derivation algebras. It is shown that G2 and its variations all possess unique nondegenerate associative forms. The authors also find some nonsingular derivations of ViG for i = 3,4, 5, 6, and thereby construct some left-symmetric structures on Vi G for i = 3,4,5,6. Some errors about the variations of sl(3, F) in [1] are corrected.展开更多
In this paper,a brief review of the history of topological insulators is given.After that,electronic transport experiments in topological insulator-superconductor hybrid structures,including experimental methods,physi...In this paper,a brief review of the history of topological insulators is given.After that,electronic transport experiments in topological insulator-superconductor hybrid structures,including experimental methods,physical properties and seemingly contradictory observations are discussed.Additionally,some new topological insulator hybrid structures are proposed.展开更多
The purpose of this study was to screen key survival-related genes from patients with colorectal cancer and explore signal transduction network of the involved genes.In a previous study,survival-related genes of patie...The purpose of this study was to screen key survival-related genes from patients with colorectal cancer and explore signal transduction network of the involved genes.In a previous study,survival-related genes of patients with colorectal cancer were selected by colorectal cancer-related expression data GSE17538 using the Significance Analysis of Microarrays(SAM3.01)software,and 235 genes related to the survival of patients with colorectal cancer were obtained.Therefore,the following screening and analysis were conducted on these 235 genes in this study.First,the enrichment analysis of transcription factor binding sites was conducted on the 235 genes.Genes with more than seven transcription factor binding sites were screened.Then,these genes and upregulated genes in colorectal cancer were intersected.Finally,survival analysis and regulatory network analysis were conducted on the screened genes.This allowed clarification of the relationship between these genes and the survival of patients with colorectal cancer and the signaling network involving these genes in the cell signal transduction network of colorectal cancer.Through the above analysis,six upregulated genes in colorectal cancer related to the survival of colorectal cancer patients and highly regulated by transcription factors were selected,namely STX2,PODXL,KLK6,GRB10,EHBP1 and CREB5.These genes are involved in signal regulatory networks related to colorectal cancer metastasis-related signaling pathways.Therefore,the survival of patients with colorectal cancer is closely correlated with colorectal cancer metastasis.The six survival-related genes affect the survival of patients by regulating colorectal cancer metastasis-associated signaling pathways.展开更多
FesoMn15-xCoxNi35 (x=0, 1, 3, 5, 7) alloys were prepared by arc melting under purified argon atmosphere. The ingots were homogenized at 930℃ for 90 h followed by water quenching. The crystal structure, magnetic pro...FesoMn15-xCoxNi35 (x=0, 1, 3, 5, 7) alloys were prepared by arc melting under purified argon atmosphere. The ingots were homogenized at 930℃ for 90 h followed by water quenching. The crystal structure, magnetic properties and magnetocaloric effects of the alloys were studied by X-ray diffraction (XRD) and MPMS-7-type SQUID. The results show that all samples still maintained a single γ-(Fe, Ni)-type phase structure. With the increase of the content of Co, the Curie temperatures of these alloys increased and exhibited a second-order magnetic transition from ferromagnetic (FM) to paramagnetic (PM) state near Curie temperature. The maximum magnetic entropy change and the relative cooling power of Fe50Mn10CosNi35 alloy was 2.55 J/kg.K and 181 J/kg, respectively, for an external field change of 5 T. Compared with rare earth metal Gd, FesoMnls-xCoxNi35 series of alloys have obvious advantage in resource price; their Curie temperatures can be tuned to near room temperature, maintain a relatively large magnetic entropy change at the same time and they are a type of potential magnetic refrigeration materials near room temperature.展开更多
To explore solvent gating of single-molecule electrical conductance due to solvent-molecule interactions, charge transport through single-molecule junctions with different anchoring groups in various solvent environme...To explore solvent gating of single-molecule electrical conductance due to solvent-molecule interactions, charge transport through single-molecule junctions with different anchoring groups in various solvent environments was measured by using the mechanically controllable break junction technique. We found that the conductance of single-molecule junctions can be tuned by nearly an order of magnitude by varying the polarity of solvent. Furthermore, gating efficiency due to solvent–molecule interactions was found to be dependent on the choice of the anchor group. Theoretical calculations revealed that the polar solvent shifted the molecular-orbital energies, based on the coupling strength of the anchor groups. For weakly coupled molecular junctions, the polar solvent–molecule interaction was observed to reduce the energy gap between the molecular orbital and the Fermi level of the electrode and shifted the molecular orbitals. This resulted in a more significant gating effect than that of the strongly coupled molecules. This study suggested that solvent–molecule interaction can significantly affect the charge transport through single-molecule junctions.展开更多
基金Project supported by the National Natural Science Foundation of China (Nos. 49771046 and 49831005) the Center for International Cooperation, Ministry of Foreign Affairs, State of Israel.
文摘Suspensions of a latosol with a clay concentration of 30 g kg^(-1) wereprepared from electrodialyzed clay fractions, less than 2 μm in diameter, five nitrate solutionswith a concentration of 1 X 10^(04)/z mol L^(-1), where z is the valence, and five sodium saltsolutions with a concentration of 3.3 X 10^(-5)/2 mol L^(-1). The direct current (DC) electricalconductivities (ECs) of the colloidal suspensions were measured at a constant temperature of 25 ℃,using a newly established method of measuring the Wien effect in soil suspensions at field strengthsranging from 13.5 to 150 kV cm^(-1), to determine their electrical conductivity-field strengthrelationships and to infer the order of the bonding strength (retaining force) between soilparticles and various ions. The measurements with the latosol suspensions in NaNO_3, KNO_3,Ca(NO_3)_2, Mg(NO_3)_2 and Zn(NO_3)_2 solutions resulted in increments of the suspension ECs, ΔECs,of 7.9, 5.0, 7.1, 7.0 and 5.8 μS cm^(-1), respectively, when the applied field strength increasedfrom 14.5 to 142 kV cm^(-1). As for the suspensions in NaNO_3, NaCl, Na_2SO_4, Na_3PO_4 andNa_3AsO_4 solutions, the ΔECs were 6.2, 5.3, 4.1, 4.0 and 3.7μS cm^(-1), respectively, when theapplied field strength increased from 13.5 to 90 kV cm^(-1). Thus, it can be deduced that theretaining forces of the clay fraction of the latosol for the cations were in the descending orderK^+ > Zn^(2+) > Mg^(2+) ≥ Ca^(2+) > Na^+, and for the anions in the descending order H_2AsO_4^- >H_2PO_4^-≥ SO_4^(2-) > Cl^- > NO_3~ -.
基金The project supported by National Natural Science Foundation of China under Grant No. 10574036, and the Natural Science Foundation of Hebei Province of China under Grant No. A2004000140
文摘In the effective-mass approximation, using a simple two-parameter wave function and a one-dimensional (ID) equivalent potential model, we calculate variationally the binding energy of an exciton bound to a neutral donor (D^0, X) in finite GaAs-AIxGa1-xAs quantum well wires (QWWs). At the wire width of 25 A, the binding energy has a peak value, which is also at the position of the peak of the exciton binding energy, and the center-of-mass wave functions of excitons reaches the most centralized distribution. In addition, the changing tendency of the average interparticle distance as the wire width is reverse to that of the binding energy.
文摘Simultaneous effects of conduction band non-parabolicity and hydrostatic pressure on the binding energies of 1S, 2S, and 2P states along with diamagnetic susceptibility of an on-center hydrogenic impurity confined in typical GaAs/Alx- Ga1-x As spherical quantum dots are theoretically investigated using the matrix diagonalization method. In this regard, the effect of band non-parabolieity has been performed using the Luttinger-Kohn effective mass equation. The binding energies and the diamagnetic susceptibility of the hydrogenic impurity are computed as a function of the dot radius and different values of the pressure in the presence of conduction band non-parabolicity effect. The results we arrived at are as follows: the incorporation of the band edge non-parabolicity increases the binding energies and decreases the absolute value of the diamagnetic susceptibility for a given pressure and radius; the binding energies increase and the magnitude of the diamagnetic susceptibility reduces with increasing pressure.
基金Supported by the National Nature Science Foundation of China under Grant Nos.10604005 and 10974015 the Program for New Century Excellent Talents in University under Grant No.NCET-08-0044
文摘Kondo transport properties through a Kondo-type quantum dot (QD) with a side-coupled triple-QD structure are systematically investigated by using the non-equilibrium Green's function method. We firstly derive the formulae of the current, the linear conductance, the transmission coefficient, and the local density of states. Then we carry out the analytical and numerical studies and some universal conductance properties are obtained. It is shown that the number of the conductance valleys is intrinsically determined by the side-coupled QDs and at most equal to the number of the QDs included in the side-coupled structure in the asymmetric limit. In the process of forming the conductance valleys, the side-coupled QD system plays the dominant role while the couplings between the Kondo-type QD and the side-coupled structure play the subsidiary and indispensable roles. To testify the validity of the universal conductance properties, another different kinds of side-coupled triple-QD structures are considered. It should be emphasized that these universal properties axe applicable in understanding this kind of systems with arbitrary many-QD side structures.
基金Project supported by the National Natural Science Foundation of China(No.10271047),the Doctoral Programme Foundation of the Ministry of Education of China and the Shanghai Priority Academic Discipline.
文摘In [1], Shen Guangyu constructed several classes of new simple Lie algebras of characteristic 2, which are called the variations of G2. In this paper, the authors investigate their derivation algebras. It is shown that G2 and its variations all possess unique nondegenerate associative forms. The authors also find some nonsingular derivations of ViG for i = 3,4, 5, 6, and thereby construct some left-symmetric structures on Vi G for i = 3,4,5,6. Some errors about the variations of sl(3, F) in [1] are corrected.
基金supported by the National Basic Research Program of China(Grant No.2012CB921300)the National Natural Science Foundation of China(Grant No.11174007)the Penn State MRSEC(Grant No. DMR-0820404)
文摘In this paper,a brief review of the history of topological insulators is given.After that,electronic transport experiments in topological insulator-superconductor hybrid structures,including experimental methods,physical properties and seemingly contradictory observations are discussed.Additionally,some new topological insulator hybrid structures are proposed.
基金supported by the Joint Funds of the National Natural Science Foundation of China(U1201226)the National Natural Science Foundation of China(30670967)
文摘The purpose of this study was to screen key survival-related genes from patients with colorectal cancer and explore signal transduction network of the involved genes.In a previous study,survival-related genes of patients with colorectal cancer were selected by colorectal cancer-related expression data GSE17538 using the Significance Analysis of Microarrays(SAM3.01)software,and 235 genes related to the survival of patients with colorectal cancer were obtained.Therefore,the following screening and analysis were conducted on these 235 genes in this study.First,the enrichment analysis of transcription factor binding sites was conducted on the 235 genes.Genes with more than seven transcription factor binding sites were screened.Then,these genes and upregulated genes in colorectal cancer were intersected.Finally,survival analysis and regulatory network analysis were conducted on the screened genes.This allowed clarification of the relationship between these genes and the survival of patients with colorectal cancer and the signaling network involving these genes in the cell signal transduction network of colorectal cancer.Through the above analysis,six upregulated genes in colorectal cancer related to the survival of colorectal cancer patients and highly regulated by transcription factors were selected,namely STX2,PODXL,KLK6,GRB10,EHBP1 and CREB5.These genes are involved in signal regulatory networks related to colorectal cancer metastasis-related signaling pathways.Therefore,the survival of patients with colorectal cancer is closely correlated with colorectal cancer metastasis.The six survival-related genes affect the survival of patients by regulating colorectal cancer metastasis-associated signaling pathways.
基金supported by the National Natural Science Foundation of China(Grant Nos.11032011 and 10872202)the Guangdong Provincial Science and Technology Program(Grant No.2010B050300008)+2 种基金the Guangzhou Municipal Science and Technology Program(Grant No.12F582080022)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry(Grant No.x2clB7120290)the Fundamental Research Funds for the Central Universities(Grant Nos.2012ZZ0013 and 2014ZZ0005)
文摘FesoMn15-xCoxNi35 (x=0, 1, 3, 5, 7) alloys were prepared by arc melting under purified argon atmosphere. The ingots were homogenized at 930℃ for 90 h followed by water quenching. The crystal structure, magnetic properties and magnetocaloric effects of the alloys were studied by X-ray diffraction (XRD) and MPMS-7-type SQUID. The results show that all samples still maintained a single γ-(Fe, Ni)-type phase structure. With the increase of the content of Co, the Curie temperatures of these alloys increased and exhibited a second-order magnetic transition from ferromagnetic (FM) to paramagnetic (PM) state near Curie temperature. The maximum magnetic entropy change and the relative cooling power of Fe50Mn10CosNi35 alloy was 2.55 J/kg.K and 181 J/kg, respectively, for an external field change of 5 T. Compared with rare earth metal Gd, FesoMnls-xCoxNi35 series of alloys have obvious advantage in resource price; their Curie temperatures can be tuned to near room temperature, maintain a relatively large magnetic entropy change at the same time and they are a type of potential magnetic refrigeration materials near room temperature.
基金This work was supported by National Key R&D Project of China(2017YFA0204902)National Natural Science Foundation of China(21722305,21673195,21973079)+2 种基金FET Open project 767187–Qu IETthe EU project BAC-TO-FUELthe UK EPSRC grants EP/N017188/1,EP/P027156/1 and EP/N03337X/1
文摘To explore solvent gating of single-molecule electrical conductance due to solvent-molecule interactions, charge transport through single-molecule junctions with different anchoring groups in various solvent environments was measured by using the mechanically controllable break junction technique. We found that the conductance of single-molecule junctions can be tuned by nearly an order of magnitude by varying the polarity of solvent. Furthermore, gating efficiency due to solvent–molecule interactions was found to be dependent on the choice of the anchor group. Theoretical calculations revealed that the polar solvent shifted the molecular-orbital energies, based on the coupling strength of the anchor groups. For weakly coupled molecular junctions, the polar solvent–molecule interaction was observed to reduce the energy gap between the molecular orbital and the Fermi level of the electrode and shifted the molecular orbitals. This resulted in a more significant gating effect than that of the strongly coupled molecules. This study suggested that solvent–molecule interaction can significantly affect the charge transport through single-molecule junctions.