Water stability is one of the most important factors restricting the practical application of metal organic frameworks (MOFs). In this work, wefabricate a highly defective HKUST-1 framework with a mixed valence of CuI...Water stability is one of the most important factors restricting the practical application of metal organic frameworks (MOFs). In this work, wefabricate a highly defective HKUST-1 framework with a mixed valence of CuI/CuIIby mechanical ball milling method. This defective HKUST-1is embellished by functionalized ionic liquids as hydrophobic armor, making the hybrid HIL1@HKUST-1 exhibits outstanding water stability,remarkable SO_(2) adsorption (up to 5.71 mmol g^(-1)), and record-breaking selectivity (1070 for SO_(2)/CO_(2) and 31,515 for SO_(2)/N_(2)) at 25 ℃ and0.1 bar, even in wet conditions.展开更多
The self-intercalation of Cr into pristine two-dimensional(2D) van der Waals ferromagnetic CrTe_(2),which forms chromium tellurides(Cr_(x)Te_(2)),has garnered interest due to their remarkable magnetic characteristics ...The self-intercalation of Cr into pristine two-dimensional(2D) van der Waals ferromagnetic CrTe_(2),which forms chromium tellurides(Cr_(x)Te_(2)),has garnered interest due to their remarkable magnetic characteristics and the wide variety of chemical compositions available.Here,comprehensive basic characterization and magnetic studies are conducted on quasi-2D ferromagnetic Cr_(1.04)Te_(2) crystals.Measurements of the isothermal magnetization curves are conducted around the critical temperature to systematically investigate the critical behavior.Specifically,the critical exponents β=0.2399,γ=0.859,and δ=4.3498,as well as the Curie temperature T_(C)=249.56 K,are determined using various methods,including the modified Arrott plots,the Kouvel-Fisher method,the Widom scaling method,and the critical isotherm analysis.These results indicate that the tricritical mean-field model accurately represents the critical behavior of Cr_(1.04)Te_(2.A magnetic phase diagram with tricritical phenomenon is thus constructed.Further investigations confirm that the critical exponents obtained conform to the scalar equation near T_(C),indicating their self-consistency and reliability.Our work sheds light on the magnetic properties of quasi-2D Cr_(1.04)Te_(2),broadening the scope of the van der Waals crystals for developments of future spintronic devices operable at room temperature.展开更多
Zn/ZSM-5（NZ2） and Zn/Ni/ZSM-5（NZ3） as the catalysts for methanol to aromatics（MTA） were synthesized by a simple ultrasonic impregnation. The textural and acid properties of all catalysts were characterized using...Zn/ZSM-5（NZ2） and Zn/Ni/ZSM-5（NZ3） as the catalysts for methanol to aromatics（MTA） were synthesized by a simple ultrasonic impregnation. The textural and acid properties of all catalysts were characterized using XRD, HRTEM, NH;-TPD, Py-IR, XPS, XRF and TG techniques. The XRD and HRTEM results showed that the basic zeolite structures were not affected much with the incorporation of Zn and Ni species. However, great changes have taken place in acid properties. The Py-IR and XPS results indicated that the Zn-Lewis acid sites（ZnOH;species）, which have stronger interaction with the zeolite framework compared with ZnO species, were generated at the expense of B acid sites with the incorporation of zinc species. Moreover, the product analysis results showed that the incorporation of zinc species promoted the primary aromatization by enhancing the dehydroaromatization and suppressing the cracking and subsequent H-transfer reaction. Furthermore, the addition of Ni species well inhibited the loss of zinc species by converting partial ZnO species to ZnOH;species, and thus improved the aromatization activity and catalyst stability. The catalytic performance results showed that the NZ3 possess higher conversion of methanol in a longer time and lower average rate of coke formation compared with NZ2. In addition,the NZ3 also exhibited the highest yield of BTX as the reaction proceeds.展开更多
vegetation restoration is a main ecological remediation technology for greening saline and alkaline soils.The objectives of this study were to determine the effect of1-aminobenzotriazole(ABT-1) on the growth and physi...vegetation restoration is a main ecological remediation technology for greening saline and alkaline soils.The objectives of this study were to determine the effect of1-aminobenzotriazole(ABT-1) on the growth and physiology of Tamarix chinensis under salt stress and to determine a suitable ABT-1 concentration and soil salinity(Sc) for propagating T.chihehsis-cuttings.Cuttings were soaked in water and ABT-1 solutions at three concentrations(50,100,and 200 mg L^(-1)) and propagated in pots containing four soil salinity levels,mild(0.3%),moderate(0.6%),and severe(0.9% and 1.2%),and compared with a control.The cuttings were measured to determine growth indices and physiological and biochemical indices(e.g.,chlorophyll content,superoxide dismutase activity,peroxidase activity,and malondialdehyde content).ABT-1 was effective in improving survival,growth,and physiological processes of cuttings under salt stress.However,there was a threshold effect when using ABT-1 to facilitate propagation under salt stress.ABT-1 effects were insignificant when applied at low concentrations(<100 mg L^(-1)).At a high concentration(> 100 mg L^(-1)),ABT-1 limited growth and physiological activities.Under a salt stress level(Sc ≤0.9%),ABT applied at a 100 mg L^(-1)concentration increased chlorophyll content and superoxide dismutase and peroxidase activities in the leaves and reduced malondialdehyde accumulation and membrane lipid peroxidation effects.As a result,ABT-1 enhanced the resistance of T.chinensis to salt stress.However,under high salt stress(>0.9%) and ABT-1 concentration(> 100 mg L^(-1)),the physiological regulatory ability of T.chinensis seedlings weakened.T.chinensis grew well at a salt stress ≤0.9% and ABT ≤100 mg L^(-1) and exhibited relatively high physiological regulatory ability and high salt adaptability.展开更多
Post-mortem methods cannot fulfill the requirement of monitoring the lifetime of the plasma facing components （PFC） and measuring the tritium inventory for the safety evaluation. Laserinduced breakdown spectroscopy ...Post-mortem methods cannot fulfill the requirement of monitoring the lifetime of the plasma facing components （PFC） and measuring the tritium inventory for the safety evaluation. Laserinduced breakdown spectroscopy （LIBS） is proposed as a promising method for the in situ study of fuel retention and impurity deposition in a tokamak. In this study, an in situ LIBS system was successfully established on EAST to investigate fuel retention and impurity deposition on the first wall without the need of removal tiles between plasma discharges. Spectral lines of D, H and impurities （Mo, Li, Si ） in laser-induced plasma were observed and identified within the wavelength range of 500-700 nm. Qualitative measurements such as thickness of the deposition layers, element depth profile and fuel retention on the wall are obtained by means of in situ LIBS. The results demonstrated the potential applications of LIBS for in situ characterization of fuel retention and co-deposition on the first wall of EAST.展开更多
Objective To investigate the effects and mechanisms of rosuvastatin on angiotensin -converting enzyme 2 (ACE2) in the process of neointimal formation after vascular balloon injury in rats, and to explore the effects o...Objective To investigate the effects and mechanisms of rosuvastatin on angiotensin -converting enzyme 2 (ACE2) in the process of neointimal formation after vascular balloon injury in rats, and to explore the effects of ACE2 and rosuvastatin in restenosis. Methods Thirty-six Wistar rats were randomly allocated into three groups: control group (n = 12), surgery group (n = 12), and statin group (n = 12). Aortic endothelial denudation of rats was performed using 2F balloon catheters. At days 14 and 28 after injury, aortic arteries were harvested to examine the following. Intimal thickening was examined by hematoxylin and eosin staining. We measured angiotensin II (Ang II) and angiotensin 1-7 (Ang-[1–7]) levels by a radioimmunological method or enzyme-linked immunosorbent assay. Protein andmRNAexpression of ACE2 and Ang II type 1 receptor (AT1) were investigated by immunohistochemistry, Western blots, and Reverse transcriptase- polymerase chain reaction (RT-PCR). We measured changes in proliferating cell nuclear antigen (PCNA) by immunohistochemistry. The level of phosphorylated extracellular signal regulated kinase 1/2 (P-ERK1/2) was evaluated byWestern blotting. Results Proliferation of vascular smooth muscle cells (VSMC) and intimal thickening were higher at day 14 after vascular balloon injury in the surgery group compared with the control group. Proliferation of VSMC was decreased by day 28 after injury, while intimal thickening continued. With rosuvastatin treatment, the extent of VSMC proliferation and intimal thickening was reduced at day 14 and 28 after injury. Ang II and P-ERK levels were significantly increased, Ang-(1–7) levels were significantly decreased, mRNA and protein expressions of ACE2 were significantly decreased, and AT1 expression was significantly increased at days 14 and 28 after vascular balloon injury in the surgery group compared with the control group. PCNAexpression was higher in the surgery group than in the control group, and it was significantly decreased after being given rosuvastatin. Expression of ACE2 mRNA and protein, and Ang-(1–7) levels were significantly increased, while AT1 expression and levels of Ang II and P-ERK were significantly decreased in the statin group compared with the surgery group. Conclusions Expression of ACE2 mRNA and protein is decreased in the process of intimal thickening after balloon injury. The inhibitory effect of rosuvastatin on intimal thickening is related to upregulation of ACE2, an increase in Ang-(1–7), downregulation of AT1, and activation of the P-ERK pathway.展开更多
Unique nanofoams consisting of interweaved ultrathin graphene confining Zn–N–C dipoles (ZnNG) are constructed via calcination of Zn-coordinated precursor.Due to the introduction of local polar Zn–N–C configuration...Unique nanofoams consisting of interweaved ultrathin graphene confining Zn–N–C dipoles (ZnNG) are constructed via calcination of Zn-coordinated precursor.Due to the introduction of local polar Zn–N–C configurations,with hypersensitivity for mechanical stress,the piezoelectricity is created on the nonpiezoelectric graphene,and the hierarchical ZnNG exhibits obvious piezocatalytic activity of water splitting for H_(2) production even under mild agitation.The corresponding rate of H_(2) production is about 14.65 μmol g^(-1)h^(-1).It triggers a breakthrough in piezocatalytic H_(2) evolution under low-frequency vibration,and takes a significant step forward for piezocatalysis towards practical applications.Furthermore,the presented concept of confining atomic polar configuration for engineering piezoelectricity would open up new horizon for constructing new-type piezoelectrics based on both piezoelectric and nonpiezoelectric materials.展开更多
Purpose: This paper aims to provide a method to detect research communities based on research interest in researcher network, which combines the topological structure and vertex attributes in a unified manner.Design/m...Purpose: This paper aims to provide a method to detect research communities based on research interest in researcher network, which combines the topological structure and vertex attributes in a unified manner.Design/methodology/approach: A heterogeneous researcher network has been constructed by combining multiple relations of academic researchers. Vertex attributes and their similarities were considered and calculated. An approach has been proposed and tested to detect research community in research organizations based on this multi-relation researcher network.Findings: Detection of topologically well-connected, semantically coherent and meaningful research community was achieved.Research limitations: The sample size of evaluation experiments was relatively small. In the present study, a limited number of 72 researchers were analyzed for constructing researcher network and detecting research community. Therefore, a large sample size is required to give more information and reliable results.Practical implications: The proposed multi-relation researcher network and approaches for discovering research communities of similar research interests will contribute to collective innovation behavior such as brainstorming and to promote interdisciplinary cooperation.Originality/value: Recent researches on community detection devote most efforts to singlerelation researcher networks and put the main focus on the topological structure of networks.In reality, there exist multi-relation social networks. Vertex attribute also plays an important role in community detection. The present study combined multiple single-relational researcher networks into a multi-relational network and proposed a structure-attribute clustering method for detecting research community in research organizations.展开更多
The famous Kadomtsev-Petviashvili(KP)equation 1 s a classical equation In soliton tneory.A Backlund transformation between the KP equation and the Schwarzian KP equation is demonstrated by means of the truncated Painl...The famous Kadomtsev-Petviashvili(KP)equation 1 s a classical equation In soliton tneory.A Backlund transformation between the KP equation and the Schwarzian KP equation is demonstrated by means of the truncated Painlev6 expansion in this paper.One-parameter group transformations and one-parameter subgroup-invariant solutions for the extended KP equation are obtained.The consistent Riccati expansion(CRE) solvability of the KP equation is proved.Some interaction structures between soliton-cnoidal waves are obtained by CRE and several evolution graphs and density graphs are plotted.展开更多
We study a forced variable-coefficient extended Korteweg-de Vries(KdV)equation in fluid dynamics with respect to internal solitary wave.Bäcklund transformations of the forced variable-coefficient extended KdV equ...We study a forced variable-coefficient extended Korteweg-de Vries(KdV)equation in fluid dynamics with respect to internal solitary wave.Bäcklund transformations of the forced variable-coefficient extended KdV equation are demonstrated with the help of truncated Painlevéexpansion.When the variable coefficients are time-periodic,the wave function evolves periodically over time.Symmetry calculation shows that the forced variable-coefficient extended KdV equation is invariant under the Galilean transformations and the scaling transformations.One-parameter group transformations and one-parameter subgroup invariant solutions are presented.Cnoidal wave solutions and solitary wave solutions of the forced variable-coefficient extended KdV equation are obtained by means of function expansion method.The consistent Riccati expansion(CRE)solvability of the forced variable-coefficient extended KdV equation is proved by means of CRE.Interaction phenomenon between cnoidal waves and solitary waves can be observed.Besides,the interaction waveform changes with the parameters.When the variable parameters are functions of time,the interaction waveform will be not regular and smooth.展开更多
Ni self-assembly has been performed on Ga N(0001), Si(111) and sapphire(0001) substrates. Scanning electron microscopy(SEM) images verify that the Si(111) substrate leads to failure of the Ni assembly due to Si–N int...Ni self-assembly has been performed on Ga N(0001), Si(111) and sapphire(0001) substrates. Scanning electron microscopy(SEM) images verify that the Si(111) substrate leads to failure of the Ni assembly due to Si–N interlayer formation; the GaN(0001) and sapphire(0001) substrates promote assembly of the Ni particles. This indicates that the GaN/sapphire(0001) substrates are fit for Ni self-assembly. For the Ni assembly process on Ga N/sapphire(0001) substrates,three differences are observed from the x-ray diffraction(XRD) patterns:(i) Ni self-assembly on the sapphire(0001) needs a 900?C annealing temperature, lower than that on the GaN(0001) at 1000?C, and loses the Ni network structure stage;(ii) the Ni particle shape is spherical for the sapphire(0001) substrate, and truncated-cone for the GaN(0001) substrate; and(iii) a Ni–N interlayer forms between the Ni particles and the GaN(0001) substrate, but an interlayer does not appear for the sapphire(0001) substrate. All these differences are attributed to the interaction between the Ni and the Ga N/sapphire(0001) substrates. A model is introduced to explain this mechanism.展开更多
A novel,simple,and effective one-step method has been developed to cut the conventional long and entangled multi-walled carbon nanotubes(MWCNTs) with nanoscissors.The cutting process was carried out by the interactive...A novel,simple,and effective one-step method has been developed to cut the conventional long and entangled multi-walled carbon nanotubes(MWCNTs) with nanoscissors.The cutting process was carried out by the interactive collision of CNTs with the silicon carbide particles adhered on the abrasive papers.The final cut nanotubes have an average length of 200~300 nm.The statistical length distribution result indicates that cutting by this method achieves high cutting efficiency for short duration of 2 min.Shortened nanotubes are found to be easily dispersed into aqueous and ethanol solutions.The cut MWCNTs/copper composite thin film fabricated by combined electrophoresis and electroplating techniques reveals that MWCNTs after cutting are well distributed and adhered to the Cu matrix.This method is not only fast and efficient but also no chemical waste,which will expand many potential applications of CNTs.展开更多
In order to study the characteristics of dust acoustic waves in a uniform dense dusty magnetoplasma system, a nonlinear dynamical equation is deduced using the quantum hydrodynamic model to account for dust–neutral c...In order to study the characteristics of dust acoustic waves in a uniform dense dusty magnetoplasma system, a nonlinear dynamical equation is deduced using the quantum hydrodynamic model to account for dust–neutral collisions. The linear dispersion relation indicates that the scale lengths of the system are revised by the quantum parameter, and that the wave motion decays gradually leading the system to a stable state eventually. The variations of the dispersion frequency with the dust concentration, collision frequency, and magnetic field strength are discussed. For the coherent nonlinear dust acoustic waves, new analytic solutions are obtained, and it is found that big shock waves and wide explosive waves may be easily produced in the background of high dusty density, strong magnetic field, and weak collision. The relevance of the obtained results is referred to dense dusty astrophysical circumstances.展开更多
Generation of attosecond electromagnetic （EM） pulses and the associated electron dynamics are studied using particle-in-cell simulations of relativistic laser pulses interacting with over-dense plasma foil targets. ...Generation of attosecond electromagnetic （EM） pulses and the associated electron dynamics are studied using particle-in-cell simulations of relativistic laser pulses interacting with over-dense plasma foil targets. The inter- action process is found to be so complicated even in the situation of utilizing driving laser pulses of only one cycle. Two electron bunches closely involved in the laser-driven wavebreaking process contribute to attosecond EM pulses through the coherent synchrotron emission process whose spectra are found to follow an exponential decay rule. Detailed investigations of electron dynamics indicate that the early part of the reflected EM emission is the high-harmonics produced through the relativistic oscillating mirror mechanism. High harmonics are also found to be generated through the Bremsstrahlung radiation by one electron bunch that participates in the wavebreaking process and decelerates when it experiences the local wavebreaking-generated high electrostatic field in the moving direction.展开更多
基金supported by the National Natural Science Foundation of China(nos.22168012 and 22208070)the Key Laboratory of Carbon-based Energy Molecular Chemical Utilization Technology in Guizhou Province(no.2023008)the Guizhou Province Outstanding Young Scientific and Technological Talents Program(no.YQK2023007).
文摘Water stability is one of the most important factors restricting the practical application of metal organic frameworks (MOFs). In this work, wefabricate a highly defective HKUST-1 framework with a mixed valence of CuI/CuIIby mechanical ball milling method. This defective HKUST-1is embellished by functionalized ionic liquids as hydrophobic armor, making the hybrid HIL1@HKUST-1 exhibits outstanding water stability,remarkable SO_(2) adsorption (up to 5.71 mmol g^(-1)), and record-breaking selectivity (1070 for SO_(2)/CO_(2) and 31,515 for SO_(2)/N_(2)) at 25 ℃ and0.1 bar, even in wet conditions.
基金Project supported by the Natural Science Foundation of Nanjing University of Posts and Telecommunications(Grant No.NY222170)Jiangsu Specially-Appointed Professor Program,and Natural Science Foundation of Universities of Jiangsu Province(Grant No.TJ219008)the support of the open research fund of Key Laboratory of Quantum Materials and Devices(Southeast University),Ministry of Education。
文摘The self-intercalation of Cr into pristine two-dimensional(2D) van der Waals ferromagnetic CrTe_(2),which forms chromium tellurides(Cr_(x)Te_(2)),has garnered interest due to their remarkable magnetic characteristics and the wide variety of chemical compositions available.Here,comprehensive basic characterization and magnetic studies are conducted on quasi-2D ferromagnetic Cr_(1.04)Te_(2) crystals.Measurements of the isothermal magnetization curves are conducted around the critical temperature to systematically investigate the critical behavior.Specifically,the critical exponents β=0.2399,γ=0.859,and δ=4.3498,as well as the Curie temperature T_(C)=249.56 K,are determined using various methods,including the modified Arrott plots,the Kouvel-Fisher method,the Widom scaling method,and the critical isotherm analysis.These results indicate that the tricritical mean-field model accurately represents the critical behavior of Cr_(1.04)Te_(2.A magnetic phase diagram with tricritical phenomenon is thus constructed.Further investigations confirm that the critical exponents obtained conform to the scalar equation near T_(C),indicating their self-consistency and reliability.Our work sheds light on the magnetic properties of quasi-2D Cr_(1.04)Te_(2),broadening the scope of the van der Waals crystals for developments of future spintronic devices operable at room temperature.
基金Supported by the Tai'an City Science and Technology Planning Program(No.2017NS0156)the High-School Scientific Research Development Program of Shandong Province(No.2016J16LL57)the Natural Scientific Foundation of Shandong Province(No.ZR2014CL011)~~
基金entrusted by the Project of "utilization of low rank coal" strategic leading special fundstrategic leading special fund of CAS (XDA-07070800 and XDA-07070400)the Opening Foundation of State Key Laboratory of Coal Conversion (J16-17-602)
文摘Zn/ZSM-5（NZ2） and Zn/Ni/ZSM-5（NZ3） as the catalysts for methanol to aromatics（MTA） were synthesized by a simple ultrasonic impregnation. The textural and acid properties of all catalysts were characterized using XRD, HRTEM, NH;-TPD, Py-IR, XPS, XRF and TG techniques. The XRD and HRTEM results showed that the basic zeolite structures were not affected much with the incorporation of Zn and Ni species. However, great changes have taken place in acid properties. The Py-IR and XPS results indicated that the Zn-Lewis acid sites（ZnOH;species）, which have stronger interaction with the zeolite framework compared with ZnO species, were generated at the expense of B acid sites with the incorporation of zinc species. Moreover, the product analysis results showed that the incorporation of zinc species promoted the primary aromatization by enhancing the dehydroaromatization and suppressing the cracking and subsequent H-transfer reaction. Furthermore, the addition of Ni species well inhibited the loss of zinc species by converting partial ZnO species to ZnOH;species, and thus improved the aromatization activity and catalyst stability. The catalytic performance results showed that the NZ3 possess higher conversion of methanol in a longer time and lower average rate of coke formation compared with NZ2. In addition,the NZ3 also exhibited the highest yield of BTX as the reaction proceeds.
基金supported financially by the National Natural Science Foundation of China (No.31770761)the Forestry Science and Technology Innovation Project of Shandong province (2019LY006)+1 种基金the Natural Science Foundation of Shandong province (No.ZR2017LEE023)the Taishan Scholars Program of Shandong province,P.R.China(No.TSQN201909152)。
文摘vegetation restoration is a main ecological remediation technology for greening saline and alkaline soils.The objectives of this study were to determine the effect of1-aminobenzotriazole(ABT-1) on the growth and physiology of Tamarix chinensis under salt stress and to determine a suitable ABT-1 concentration and soil salinity(Sc) for propagating T.chihehsis-cuttings.Cuttings were soaked in water and ABT-1 solutions at three concentrations(50,100,and 200 mg L^(-1)) and propagated in pots containing four soil salinity levels,mild(0.3%),moderate(0.6%),and severe(0.9% and 1.2%),and compared with a control.The cuttings were measured to determine growth indices and physiological and biochemical indices(e.g.,chlorophyll content,superoxide dismutase activity,peroxidase activity,and malondialdehyde content).ABT-1 was effective in improving survival,growth,and physiological processes of cuttings under salt stress.However,there was a threshold effect when using ABT-1 to facilitate propagation under salt stress.ABT-1 effects were insignificant when applied at low concentrations(<100 mg L^(-1)).At a high concentration(> 100 mg L^(-1)),ABT-1 limited growth and physiological activities.Under a salt stress level(Sc ≤0.9%),ABT applied at a 100 mg L^(-1)concentration increased chlorophyll content and superoxide dismutase and peroxidase activities in the leaves and reduced malondialdehyde accumulation and membrane lipid peroxidation effects.As a result,ABT-1 enhanced the resistance of T.chinensis to salt stress.However,under high salt stress(>0.9%) and ABT-1 concentration(> 100 mg L^(-1)),the physiological regulatory ability of T.chinensis seedlings weakened.T.chinensis grew well at a salt stress ≤0.9% and ABT ≤100 mg L^(-1) and exhibited relatively high physiological regulatory ability and high salt adaptability.
基金Supported by the National Magnetic Confinement Fusion Science Program of China(Nos.2013GB105002,2015GB109001,and 2013GB109005)National Natural Science Foundation of China(Nos.11575243,11605238,11605023)+1 种基金Chinesisch-Deutsches Forschungs Project(GZ765)Korea Research Council of Fundamental Science and Technology(KRCF)under the international collaboration&research in Asian countries(PG1314)
文摘Post-mortem methods cannot fulfill the requirement of monitoring the lifetime of the plasma facing components （PFC） and measuring the tritium inventory for the safety evaluation. Laserinduced breakdown spectroscopy （LIBS） is proposed as a promising method for the in situ study of fuel retention and impurity deposition in a tokamak. In this study, an in situ LIBS system was successfully established on EAST to investigate fuel retention and impurity deposition on the first wall without the need of removal tiles between plasma discharges. Spectral lines of D, H and impurities （Mo, Li, Si ） in laser-induced plasma were observed and identified within the wavelength range of 500-700 nm. Qualitative measurements such as thickness of the deposition layers, element depth profile and fuel retention on the wall are obtained by means of in situ LIBS. The results demonstrated the potential applications of LIBS for in situ characterization of fuel retention and co-deposition on the first wall of EAST.
基金This study was supported by the National Nature Science Foundation of China
文摘Objective To investigate the effects and mechanisms of rosuvastatin on angiotensin -converting enzyme 2 (ACE2) in the process of neointimal formation after vascular balloon injury in rats, and to explore the effects of ACE2 and rosuvastatin in restenosis. Methods Thirty-six Wistar rats were randomly allocated into three groups: control group (n = 12), surgery group (n = 12), and statin group (n = 12). Aortic endothelial denudation of rats was performed using 2F balloon catheters. At days 14 and 28 after injury, aortic arteries were harvested to examine the following. Intimal thickening was examined by hematoxylin and eosin staining. We measured angiotensin II (Ang II) and angiotensin 1-7 (Ang-[1–7]) levels by a radioimmunological method or enzyme-linked immunosorbent assay. Protein andmRNAexpression of ACE2 and Ang II type 1 receptor (AT1) were investigated by immunohistochemistry, Western blots, and Reverse transcriptase- polymerase chain reaction (RT-PCR). We measured changes in proliferating cell nuclear antigen (PCNA) by immunohistochemistry. The level of phosphorylated extracellular signal regulated kinase 1/2 (P-ERK1/2) was evaluated byWestern blotting. Results Proliferation of vascular smooth muscle cells (VSMC) and intimal thickening were higher at day 14 after vascular balloon injury in the surgery group compared with the control group. Proliferation of VSMC was decreased by day 28 after injury, while intimal thickening continued. With rosuvastatin treatment, the extent of VSMC proliferation and intimal thickening was reduced at day 14 and 28 after injury. Ang II and P-ERK levels were significantly increased, Ang-(1–7) levels were significantly decreased, mRNA and protein expressions of ACE2 were significantly decreased, and AT1 expression was significantly increased at days 14 and 28 after vascular balloon injury in the surgery group compared with the control group. PCNAexpression was higher in the surgery group than in the control group, and it was significantly decreased after being given rosuvastatin. Expression of ACE2 mRNA and protein, and Ang-(1–7) levels were significantly increased, while AT1 expression and levels of Ang II and P-ERK were significantly decreased in the statin group compared with the surgery group. Conclusions Expression of ACE2 mRNA and protein is decreased in the process of intimal thickening after balloon injury. The inhibitory effect of rosuvastatin on intimal thickening is related to upregulation of ACE2, an increase in Ang-(1–7), downregulation of AT1, and activation of the P-ERK pathway.
基金supported by the National Natural Science Foundation of China (21802007)the Natural Science Foundation of Hunan Province (2020JJ5615)+1 种基金the Scientific Research Project of Hunan Provincial Department of Education (20B066)the Open Project Program of the State Key Laboratory of Photocatalysis on Energy and Environment (SKLPEE-202001), Fuzhou University。
文摘Unique nanofoams consisting of interweaved ultrathin graphene confining Zn–N–C dipoles (ZnNG) are constructed via calcination of Zn-coordinated precursor.Due to the introduction of local polar Zn–N–C configurations,with hypersensitivity for mechanical stress,the piezoelectricity is created on the nonpiezoelectric graphene,and the hierarchical ZnNG exhibits obvious piezocatalytic activity of water splitting for H_(2) production even under mild agitation.The corresponding rate of H_(2) production is about 14.65 μmol g^(-1)h^(-1).It triggers a breakthrough in piezocatalytic H_(2) evolution under low-frequency vibration,and takes a significant step forward for piezocatalysis towards practical applications.Furthermore,the presented concept of confining atomic polar configuration for engineering piezoelectricity would open up new horizon for constructing new-type piezoelectrics based on both piezoelectric and nonpiezoelectric materials.
基金supported by the National Natural Science Foundation of China(Grant No.:71203164)
文摘Purpose: This paper aims to provide a method to detect research communities based on research interest in researcher network, which combines the topological structure and vertex attributes in a unified manner.Design/methodology/approach: A heterogeneous researcher network has been constructed by combining multiple relations of academic researchers. Vertex attributes and their similarities were considered and calculated. An approach has been proposed and tested to detect research community in research organizations based on this multi-relation researcher network.Findings: Detection of topologically well-connected, semantically coherent and meaningful research community was achieved.Research limitations: The sample size of evaluation experiments was relatively small. In the present study, a limited number of 72 researchers were analyzed for constructing researcher network and detecting research community. Therefore, a large sample size is required to give more information and reliable results.Practical implications: The proposed multi-relation researcher network and approaches for discovering research communities of similar research interests will contribute to collective innovation behavior such as brainstorming and to promote interdisciplinary cooperation.Originality/value: Recent researches on community detection devote most efforts to singlerelation researcher networks and put the main focus on the topological structure of networks.In reality, there exist multi-relation social networks. Vertex attribute also plays an important role in community detection. The present study combined multiple single-relational researcher networks into a multi-relational network and proposed a structure-attribute clustering method for detecting research community in research organizations.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11775047,11775146,and 11865013)the Science and Technology Project Foundation of Zhongshan City,China(Grant No.2017B1016).
文摘The famous Kadomtsev-Petviashvili(KP)equation 1 s a classical equation In soliton tneory.A Backlund transformation between the KP equation and the Schwarzian KP equation is demonstrated by means of the truncated Painlev6 expansion in this paper.One-parameter group transformations and one-parameter subgroup-invariant solutions for the extended KP equation are obtained.The consistent Riccati expansion(CRE) solvability of the KP equation is proved.Some interaction structures between soliton-cnoidal waves are obtained by CRE and several evolution graphs and density graphs are plotted.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11775047,11775146,and 11865013).
文摘We study a forced variable-coefficient extended Korteweg-de Vries(KdV)equation in fluid dynamics with respect to internal solitary wave.Bäcklund transformations of the forced variable-coefficient extended KdV equation are demonstrated with the help of truncated Painlevéexpansion.When the variable coefficients are time-periodic,the wave function evolves periodically over time.Symmetry calculation shows that the forced variable-coefficient extended KdV equation is invariant under the Galilean transformations and the scaling transformations.One-parameter group transformations and one-parameter subgroup invariant solutions are presented.Cnoidal wave solutions and solitary wave solutions of the forced variable-coefficient extended KdV equation are obtained by means of function expansion method.The consistent Riccati expansion(CRE)solvability of the forced variable-coefficient extended KdV equation is proved by means of CRE.Interaction phenomenon between cnoidal waves and solitary waves can be observed.Besides,the interaction waveform changes with the parameters.When the variable parameters are functions of time,the interaction waveform will be not regular and smooth.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61473266 and 61673404)the Program for Science&Technology Innovation Talents in Universities of Henan Province,China(Grant No.16HASTIT033)+2 种基金the Science and Technique Foundation of Henan Province,China(Grant Nos.132102210521,152102210153,182102210516,and 172102210601)the Key Program in Universities of Henan Province,China(Grant No.17B520044)the Science and Technique Project of the China National Textile and Apparel Council(Grant No.2018104)
文摘Ni self-assembly has been performed on Ga N(0001), Si(111) and sapphire(0001) substrates. Scanning electron microscopy(SEM) images verify that the Si(111) substrate leads to failure of the Ni assembly due to Si–N interlayer formation; the GaN(0001) and sapphire(0001) substrates promote assembly of the Ni particles. This indicates that the GaN/sapphire(0001) substrates are fit for Ni self-assembly. For the Ni assembly process on Ga N/sapphire(0001) substrates,three differences are observed from the x-ray diffraction(XRD) patterns:(i) Ni self-assembly on the sapphire(0001) needs a 900?C annealing temperature, lower than that on the GaN(0001) at 1000?C, and loses the Ni network structure stage;(ii) the Ni particle shape is spherical for the sapphire(0001) substrate, and truncated-cone for the GaN(0001) substrate; and(iii) a Ni–N interlayer forms between the Ni particles and the GaN(0001) substrate, but an interlayer does not appear for the sapphire(0001) substrate. All these differences are attributed to the interaction between the Ni and the Ga N/sapphire(0001) substrates. A model is introduced to explain this mechanism.
基金supported by National Natural Science Foundation of China (Grant No.50730008 and 50902092)Shanghai Science & Technology foundation (Grant No.1052nm02000 and 1052nm06800)Scientific Innovation Program of Shanghai (Grant No.09JC1407400)
文摘A novel,simple,and effective one-step method has been developed to cut the conventional long and entangled multi-walled carbon nanotubes(MWCNTs) with nanoscissors.The cutting process was carried out by the interactive collision of CNTs with the silicon carbide particles adhered on the abrasive papers.The final cut nanotubes have an average length of 200~300 nm.The statistical length distribution result indicates that cutting by this method achieves high cutting efficiency for short duration of 2 min.Shortened nanotubes are found to be easily dispersed into aqueous and ethanol solutions.The cut MWCNTs/copper composite thin film fabricated by combined electrophoresis and electroplating techniques reveals that MWCNTs after cutting are well distributed and adhered to the Cu matrix.This method is not only fast and efficient but also no chemical waste,which will expand many potential applications of CNTs.
基金supported by the National Natural Science Foundation of China(Grant Nos.11365017,11465015,11305031,11405110,and 11275123)the Technology Landing Project of the Education Department of Jiangxi Province of China(Grant No.KJLD13086)
文摘In order to study the characteristics of dust acoustic waves in a uniform dense dusty magnetoplasma system, a nonlinear dynamical equation is deduced using the quantum hydrodynamic model to account for dust–neutral collisions. The linear dispersion relation indicates that the scale lengths of the system are revised by the quantum parameter, and that the wave motion decays gradually leading the system to a stable state eventually. The variations of the dispersion frequency with the dust concentration, collision frequency, and magnetic field strength are discussed. For the coherent nonlinear dust acoustic waves, new analytic solutions are obtained, and it is found that big shock waves and wide explosive waves may be easily produced in the background of high dusty density, strong magnetic field, and weak collision. The relevance of the obtained results is referred to dense dusty astrophysical circumstances.
基金Supported by the National Natural Science Foundation of China under Grant No 11674146the National Basic Research Program of China under Grant No 2013CBA01500
文摘Generation of attosecond electromagnetic （EM） pulses and the associated electron dynamics are studied using particle-in-cell simulations of relativistic laser pulses interacting with over-dense plasma foil targets. The inter- action process is found to be so complicated even in the situation of utilizing driving laser pulses of only one cycle. Two electron bunches closely involved in the laser-driven wavebreaking process contribute to attosecond EM pulses through the coherent synchrotron emission process whose spectra are found to follow an exponential decay rule. Detailed investigations of electron dynamics indicate that the early part of the reflected EM emission is the high-harmonics produced through the relativistic oscillating mirror mechanism. High harmonics are also found to be generated through the Bremsstrahlung radiation by one electron bunch that participates in the wavebreaking process and decelerates when it experiences the local wavebreaking-generated high electrostatic field in the moving direction.
