The research explored effects of cultivation methods on growth, yield and quality of cassava. The results showed that the mulching treatment by direct seed- ing, the mulching treatment by transplanting, and the expose...The research explored effects of cultivation methods on growth, yield and quality of cassava. The results showed that the mulching treatment by direct seed- ing, the mulching treatment by transplanting, and the exposed treatment by trans- planting performed excellently in bringing seedling stage forward, improving germina- tion rate, yield and quality. For example, seedling emergence stages were 36, 31 and 31 d earlier; germination rates improved by 19.24%, 14.29% and 14.29%; yields grew by 41.98%, 26.72% and 11.45%; starch contents increased by 3.50%, 2.10% and 1.40%, respectively. Therefore, cassava in the mulching treatment by direct seeding is characterized by earlier seedling emergence stage, high germination rate, high yield and quality.展开更多
A compact drain current including the variation of barrier heights and carrier quantization in ultrathin-body and double-gate Schottky barrier MOSFETs (UTBDG SBFETs) is developed. In this model, Schrodinger's equat...A compact drain current including the variation of barrier heights and carrier quantization in ultrathin-body and double-gate Schottky barrier MOSFETs (UTBDG SBFETs) is developed. In this model, Schrodinger's equation is solved using the triangular potential well approximation. The carrier density thus obtained is included in the space charge density to obtain quantum carrier confinement effects in the modeling of thin-body devices. Due to the quantum effects, the first subband is higher than the conduction band edge, which is equivalent to the band gap widening. Thus, the barrier heights at the source and drain increase and the carrier concentration decreases as the drain current decreases. The drawback of the existing models,which cannot present an accurate prediction of the drain current because they mainly consider the effects of Schottky barrier lowering (SBL) due to image forces,is eliminated. Our research results suggest that for small nonnegative Schottky barrier (SB) heights,even for zero barrier height, the tunneling current also plays a role in the total on-state currents. Verification of the present model was carried out by the device numerical simulator-Silvaco and showed good agreement.展开更多
Five cytoplasmic male sterile (CMS) lines were used as parents in an incomplete diallet cross and six restorer lines of rice design (Nc II design). Thirty hybrid combinations with the same growth period were selec...Five cytoplasmic male sterile (CMS) lines were used as parents in an incomplete diallet cross and six restorer lines of rice design (Nc II design). Thirty hybrid combinations with the same growth period were selected as experimental ma- terials to investigate the heterosis, combined ability and heredity of Cd content in brown rice of indica hybrid rice. According to the results, Cd content in brown rice showed a significantly negative heterosis; the general combining ability and specific combination ability of Cd content in CMS and restorer lines both reached extremely significant level (P〈0.01), indicating that both genetic improvement of parents and e- valuation of combinations are important to the breeding of hybrid combinations with low accumulation of Cd; the broad-sense heritabitity and narrow-sense heritability of Cd content were both relatively high with slight differences, which respectively reached 97.73% and 80.10%, indicating that Cd content in brown rice mainly de- pends on the additive action of genes; in addition, parent improvement showed bet- ter effect on the selection of early generation.展开更多
AIM To retrospectively review patients with chronic pancreatitis(CP) treated with Frey's procedures between January 2009 and January 2014.METHODS A retrospective review was performed of patients with CP treated wi...AIM To retrospectively review patients with chronic pancreatitis(CP) treated with Frey's procedures between January 2009 and January 2014.METHODS A retrospective review was performed of patients with CP treated with Frey's procedures between January 2009 and January 2014 in the Department of Pancreatic Surgery. A cross-sectional study of postoperative pain relief, quality of life(Qo L), and alcohol and nicotine abuse was performed by clinical interview, letters and telephone interview in January 2016. Qo L of patients was evaluated with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire(EORTC QLQ-C30) version 3.0. The patients were requested to fill in the questionnaires by themselves via correspondence or clinical interview.RESULTS A total of 80 patients were enrolled for analysis, including 44 who underwent the original Frey's procedure and 36 who underwent a modified Frey's procedure. The mean age was 46 years in the original group and 48 years in the modified group. Thirtyfive male patients(80%) were in the original group and 33(92%) in the modified group. There were no differences in the operating time, blood loss, and postoperative morbidity and mortality between the two groups. The mean follow-up was 50.3 mo in the original group and 48.7 mo in the modified group. There were no differences in endocrine and exocrine function preservation between the two groups. The original Frey's procedure resulted in significantly betterpain relief, as shown by 5-year follow-up(P = 0.032), better emotional status(P = 0.047) and fewer fatigue symptoms(P = 0.028). When stratifying these patients by the M-ANNHEIM severity index, no impact was found on pain relief after the two types of surgery.CONCLUSION The original Frey's procedure is as safe as the modified procedure, but the former yields better pain relief. The severity of CP does not affect postoperative pain relief.展开更多
The research and development history of silicon Neutron Transmutation Doping (NTD) technology and its applications at home and abroad are introduced in this paper.The advantages of NTD,compared with conventional techn...The research and development history of silicon Neutron Transmutation Doping (NTD) technology and its applications at home and abroad are introduced in this paper.The advantages of NTD,compared with conventional technology of doping,are narrated.The principle of NTD as well as the implementation of the main procedures related to Si NTD is explained.The market demand tendency is prospected,and the advanced measures on NTD quality control are described.展开更多
In the current economic situation, strengthening the contract management of the construction cost has a beautifully role. At the same time, according to construction project cost management, the scientific management ...In the current economic situation, strengthening the contract management of the construction cost has a beautifully role. At the same time, according to construction project cost management, the scientific management of the contract, can promote the reasonable and balanced investment cost allocation in the quality and safety and other aspects of the project, so that the construction project can obtain higher added value, and to further promote China' s economic construction and accelerate the pace of the city. This paper first briefly elaborates our construction project cost of the contract management on the present situation, and some problems are analyzed and discussed, and then puts forward some suggestions on the measures and countermeasures for cost management of construction engineering contract.展开更多
Even though radio broadcasting is one of the most widespread electronic mass media, its management for survival is getting drastic. The competition among incumbent radio stations becomes challenging due to the market ...Even though radio broadcasting is one of the most widespread electronic mass media, its management for survival is getting drastic. The competition among incumbent radio stations becomes challenging due to the market change and environmental evolution. Managing program quality is a critical issue to a radio station to sharpen its competitive advantages. Quality management of radio programs is intertwined with complicated factors. In order to identify the primary factors affecting radio program quality as well as explore the impact level these factors bring, this study adopts modified Delphi method and analytic hierarchy process (AHP) to explore the issues. According to the outcomes modified Delphi method, the factors were categorized into four dimensions: operation, coordination, structure, and improvement. Ten sub-dimensions were followed. Each sub-dimension includes six to nineteen indicators for measuring radio program quality. In total, 72 indicators were identified. The AHP result revealed that the most important weight was given to the operation dimension. On the contrary, the least important weight was placed on the improvement dimension. Among the sub-dimensions, the standard procedure and organizational design were rated more important than the rest. The results could provide some facts to radio managers for future management.展开更多
The bound-state solution of the position dependent mass Klein-Gordon equation including inversely linear potential is obtained within the framework of the asymptotic iteration method. The relation between the scalar a...The bound-state solution of the position dependent mass Klein-Gordon equation including inversely linear potential is obtained within the framework of the asymptotic iteration method. The relation between the scalar and vector potentials is considered to S(x) = V(x)(β - 1). In particular, it is shown that the corresponding method exactly reproduces the spectrum of linearly inversely potentials with spatially dependent mass.展开更多
Using the coupled Dyson-Schwinger equation for the fermion propagator at finite chemical potential μ, we investigate the fermion chiral condensate when the gauge boson mass is nonzero in QED3. We show that the chiral...Using the coupled Dyson-Schwinger equation for the fermion propagator at finite chemical potential μ, we investigate the fermion chiral condensate when the gauge boson mass is nonzero in QED3. We show that the chiral symmetry restores when the boson mass is large enough, and the critical boson mass depends little on μ.展开更多
The soil drought stress experiment in different durations (no watering within 3d, 6d, 9d, 11d individually) was conducted to study the drought-resistant capacity of one-year-old seedlings for the native tree species (...The soil drought stress experiment in different durations (no watering within 3d, 6d, 9d, 11d individually) was conducted to study the drought-resistant capacity of one-year-old seedlings for the native tree species (Machilus yunnanensis) in Yunnan Province and the introduced tree species (Cinnamomum camphora). The leaf water potential, chlorophyll content, proline content and plasma membrane permeability for two species seedlings were measured in different soil drought conditions. The results showed that, on the 9th day of drought stress, the leaf water potential of two species decreased obviously, whereas the free proline content and plasma membrane permeability increased sharply. On the 11th day, the leaf water potential of C. camphora seedlings was lower than that of M. yunnanensis seedlings; the plasma membrane permeability in C. camphora seedling leaves increased much more than that in M. yunnanensis seedling leaves, which showed that the injury to the former by soil drought stress was more severe than that to the latter. The free proline content in M. yunnanensis seedling leaves continued to increase on the 11th day, but that in the C. camphora seedling leaves started to drop obviously, indicating that the reduction of osmotic regulation substance in C. camphora seedling leaves after the 11th day was unable to maintain the osmotic balance between the plasma system and its surroundings and the water loss occurred inevitably. Comprehensively, M. yunnanensis seedlings enhanced the drought-resistance in the course of soil drought stress by maintaining higher leaf water potential and by increasing osmotic regulation substance to promote cell plasma concentration and maintain membrane structure integrity so as to reduce water loss. The subordination function index evaluated with fuzzy mathematic theory also showed that the drought-resistant capacity of M. yunnanensis seedlings was stronger than that of C. camphora seedlings.展开更多
The N/Z ratio of free nucleons from collisions of neutron-rich nuclei as a function of their momentum is studied by means of isospin-dependent Quantum Molecular Dynamics. We find that this ratio is not only sensitive ...The N/Z ratio of free nucleons from collisions of neutron-rich nuclei as a function of their momentum is studied by means of isospin-dependent Quantum Molecular Dynamics. We find that this ratio is not only sensitive to the form of the density dependence of the symmetry potential energy but also its strength determined by the symmetry energy coefficient. The uncertainties about the symmetry energy coefficient influence the accuracy of probing the density dependence of the symmetry energy by means of the N/Z ratio of free nucleons of neutron-rich nuclei.展开更多
With the rapid development of economy in our country, the level of science and technology innovation, all of these prolong the life span of our life. Thus an aging population are increasingly highlight, which are deep...With the rapid development of economy in our country, the level of science and technology innovation, all of these prolong the life span of our life. Thus an aging population are increasingly highlight, which are deeply and widely influenced our society, economy, life and other aspects. As the basic insurance which maintain the elderly's life quality after they retired, Pension insurance will promove social stability and development. How to reform Pension insurance under the background of the aging of the population will get more and more attention from people. This article starts with the concept of the aging of the population and its development trend. Next, the article analyses the problems of Pension Insurance under the background of the aging of the population. Last, the article summarizes countermeasures according to solve these matters.展开更多
A (3+1 )-dimensional Kadomtse-Petviashvili (KP) equation for nonlinearly interacting intense laser pulses with an electron-positron (e-p) plasma is derived. Taking into account the combined action of the relati...A (3+1 )-dimensional Kadomtse-Petviashvili (KP) equation for nonlinearly interacting intense laser pulses with an electron-positron (e-p) plasma is derived. Taking into account the combined action of the relativistic particle mass increase and the relativistic light ponderomotive force, using the perturbation method, and allowing different types solution, we discuss the analytical solution of (3+1)-dimensional KP-I equation, and give the approximate solutions of vector potential of the intense laser pulse in e-p plasma. Our results may be significantly useful in understanding the nonlinear wave propagation and interaction of intense laser beams in an e-p plasma.展开更多
For the purpose of enhancing automobile safety and the effectiveness of recalls,increasing manufacturers' quality control capabilities,and reducing defects,we investigated thestatus of recalls over the last five y...For the purpose of enhancing automobile safety and the effectiveness of recalls,increasing manufacturers' quality control capabilities,and reducing defects,we investigated thestatus of recalls over the last five years.We have examined patterns and trends in motor vehiclesafety recalls using databases from China,Europe and the United States.A recall rate parameterwas developed to evaluate the level of recall enforcement based on analyzing the reasonsfor recalls and manufactures' characteristics.Moreover,there were substantial differencesin the recall rates of China compared with those in other countries,indicating that Chinese manufacturersneed to take more active action in recall.展开更多
Here we used Empirical Mode Decomposition (EMD) method to study seasonal variability and nonlinear trend of corrected AERONET Aerosol Optical Depth (AOD/Hi) and corrected PM10 mass concentrations (PMmxf(RH)) i...Here we used Empirical Mode Decomposition (EMD) method to study seasonal variability and nonlinear trend of corrected AERONET Aerosol Optical Depth (AOD/Hi) and corrected PM10 mass concentrations (PMmxf(RH)) in Hong Kong during 2005-2011. AODPrli is highly correlated with PMI0xf(RH) in semi-annual and annual time scales (with correlation coefficient 0.67 for semi-annual and 0.79 for annual components, 95% confidence interval). On the semi-annual scale, both AOD/Hi and PM10xf(RH) can capture the two maxima in March and October, respectively, with much stronger amplitude in March proba- bly due to the long-range transport of dust storm. On the annual cycle, the AOD/Hi and PMI0xf(RH), which are negatively correlated with the precipitation and solar radiation, vary coherently with the maxima in February. This annual peak occurs about one month earlier than the first peak of the semi-annual variability in March, but with only half amplitude. During 2005-2011, both AOD/Hi and PM10xf(RH) exhibit the pronounced decreasing trend with the mean rate of 14 gg m-3 per year for PM10xf(RH), which reflects the significant effects of the air pollution control policy in Hong Kong during the past decade. The nonlinear trend analysis indicates that the decreasing of PM10xf(RH) is slower than that of AOD/Hi when the AOD/Hi is less than 0.44 but becomes faster when the AOD/Hi exceeds 0.44. These results illustrate that the AERONET AOD can be used quantitatively to estimate local air-quality variability on the semi-annual, annual, and long-term trend time scales.展开更多
Large roughness and structure disorder in ferroelectric ultrathin Langmuir-Blodgett(LB)film results in severe space scatter in electrical,ferroelectric and piezoelectric characteristics,thus limiting the nanoscale res...Large roughness and structure disorder in ferroelectric ultrathin Langmuir-Blodgett(LB)film results in severe space scatter in electrical,ferroelectric and piezoelectric characteristics,thus limiting the nanoscale research and reliability of nano-devices.However,no effective method aiming at large-area uniform organic ferroelectric LB film has ever been reported to date.Herein,we present a facile hot-pressing strategy to prepare relatively large-area poly(vinylidene fluoride)(PVDF)LB film with ultra-smooth surface root mean square(RMS)roughness is 0.3 nm in a 30μm×30μm area comparable to that of metal substrate,which maximized the potential of LB technique to control thickness distribution.More importantly,compared with traditionally annealed LB film,the hot-pressed LB film manifests significantly improved structure uniformity,less fluctuation in ferroelectric characteristics and higher dielectric and piezoelectric responses,owing to the uniform dipole orientation and higher crystalline quality.Besides,different surface charge relaxation behaviors are investigated and the underlying mechanisms are explained in the light of the interplay of surface charge and polarization charge in the case of nanoscale non-uniform switching.We believe that our work not only presents a novel strategy to endow PVDF LB film with unprecedented reliability and improved performance as a competitive candidate for future ferroelectric tunnel junctions(FTJs)and nano electro mechanical systems(NEMS),but also reveals an attracting coupling effect between the surface potential distribution and nanoscale non-uniform switching behavior,which is crucial for the understanding of local transport characterization modulated by band structure,bit signal stability for data-storage application and the related surface charge research,such as charge gradient microscopy(CGM)based on the collection of surface charge on the biased ferroelectric domains.展开更多
Vector meson mass values are studied at finite chemical potential and temperature in lattice QCD with lattice size of 24 × 122× 6 using two flavors of staggered quarks. The investigation focuses on the chang...Vector meson mass values are studied at finite chemical potential and temperature in lattice QCD with lattice size of 24 × 122× 6 using two flavors of staggered quarks. The investigation focuses on the change of the vector meson mass in the critical region close to T c with two different types of chemical potentials switched on: the isoscalar chemical potential μS and its isovector counterpart μV. It is found that the vector meson mass increases in the QGP phase with both chemical potentials and decreases with μS in the confinement phase.展开更多
基金Supported by the Earmarked Fund for China Agriculture Research System(CARS-12)~~
文摘The research explored effects of cultivation methods on growth, yield and quality of cassava. The results showed that the mulching treatment by direct seed- ing, the mulching treatment by transplanting, and the exposed treatment by trans- planting performed excellently in bringing seedling stage forward, improving germina- tion rate, yield and quality. For example, seedling emergence stages were 36, 31 and 31 d earlier; germination rates improved by 19.24%, 14.29% and 14.29%; yields grew by 41.98%, 26.72% and 11.45%; starch contents increased by 3.50%, 2.10% and 1.40%, respectively. Therefore, cassava in the mulching treatment by direct seeding is characterized by earlier seedling emergence stage, high germination rate, high yield and quality.
文摘A compact drain current including the variation of barrier heights and carrier quantization in ultrathin-body and double-gate Schottky barrier MOSFETs (UTBDG SBFETs) is developed. In this model, Schrodinger's equation is solved using the triangular potential well approximation. The carrier density thus obtained is included in the space charge density to obtain quantum carrier confinement effects in the modeling of thin-body devices. Due to the quantum effects, the first subband is higher than the conduction band edge, which is equivalent to the band gap widening. Thus, the barrier heights at the source and drain increase and the carrier concentration decreases as the drain current decreases. The drawback of the existing models,which cannot present an accurate prediction of the drain current because they mainly consider the effects of Schottky barrier lowering (SBL) due to image forces,is eliminated. Our research results suggest that for small nonnegative Schottky barrier (SB) heights,even for zero barrier height, the tunneling current also plays a role in the total on-state currents. Verification of the present model was carried out by the device numerical simulator-Silvaco and showed good agreement.
基金Supported by Youth Fund Project of Sichuan Academy of Agricultural Sciences(2009QNJJ015)~~
文摘Five cytoplasmic male sterile (CMS) lines were used as parents in an incomplete diallet cross and six restorer lines of rice design (Nc II design). Thirty hybrid combinations with the same growth period were selected as experimental ma- terials to investigate the heterosis, combined ability and heredity of Cd content in brown rice of indica hybrid rice. According to the results, Cd content in brown rice showed a significantly negative heterosis; the general combining ability and specific combination ability of Cd content in CMS and restorer lines both reached extremely significant level (P〈0.01), indicating that both genetic improvement of parents and e- valuation of combinations are important to the breeding of hybrid combinations with low accumulation of Cd; the broad-sense heritabitity and narrow-sense heritability of Cd content were both relatively high with slight differences, which respectively reached 97.73% and 80.10%, indicating that Cd content in brown rice mainly de- pends on the additive action of genes; in addition, parent improvement showed bet- ter effect on the selection of early generation.
文摘AIM To retrospectively review patients with chronic pancreatitis(CP) treated with Frey's procedures between January 2009 and January 2014.METHODS A retrospective review was performed of patients with CP treated with Frey's procedures between January 2009 and January 2014 in the Department of Pancreatic Surgery. A cross-sectional study of postoperative pain relief, quality of life(Qo L), and alcohol and nicotine abuse was performed by clinical interview, letters and telephone interview in January 2016. Qo L of patients was evaluated with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire(EORTC QLQ-C30) version 3.0. The patients were requested to fill in the questionnaires by themselves via correspondence or clinical interview.RESULTS A total of 80 patients were enrolled for analysis, including 44 who underwent the original Frey's procedure and 36 who underwent a modified Frey's procedure. The mean age was 46 years in the original group and 48 years in the modified group. Thirtyfive male patients(80%) were in the original group and 33(92%) in the modified group. There were no differences in the operating time, blood loss, and postoperative morbidity and mortality between the two groups. The mean follow-up was 50.3 mo in the original group and 48.7 mo in the modified group. There were no differences in endocrine and exocrine function preservation between the two groups. The original Frey's procedure resulted in significantly betterpain relief, as shown by 5-year follow-up(P = 0.032), better emotional status(P = 0.047) and fewer fatigue symptoms(P = 0.028). When stratifying these patients by the M-ANNHEIM severity index, no impact was found on pain relief after the two types of surgery.CONCLUSION The original Frey's procedure is as safe as the modified procedure, but the former yields better pain relief. The severity of CP does not affect postoperative pain relief.
文摘The research and development history of silicon Neutron Transmutation Doping (NTD) technology and its applications at home and abroad are introduced in this paper.The advantages of NTD,compared with conventional technology of doping,are narrated.The principle of NTD as well as the implementation of the main procedures related to Si NTD is explained.The market demand tendency is prospected,and the advanced measures on NTD quality control are described.
文摘In the current economic situation, strengthening the contract management of the construction cost has a beautifully role. At the same time, according to construction project cost management, the scientific management of the contract, can promote the reasonable and balanced investment cost allocation in the quality and safety and other aspects of the project, so that the construction project can obtain higher added value, and to further promote China' s economic construction and accelerate the pace of the city. This paper first briefly elaborates our construction project cost of the contract management on the present situation, and some problems are analyzed and discussed, and then puts forward some suggestions on the measures and countermeasures for cost management of construction engineering contract.
文摘Even though radio broadcasting is one of the most widespread electronic mass media, its management for survival is getting drastic. The competition among incumbent radio stations becomes challenging due to the market change and environmental evolution. Managing program quality is a critical issue to a radio station to sharpen its competitive advantages. Quality management of radio programs is intertwined with complicated factors. In order to identify the primary factors affecting radio program quality as well as explore the impact level these factors bring, this study adopts modified Delphi method and analytic hierarchy process (AHP) to explore the issues. According to the outcomes modified Delphi method, the factors were categorized into four dimensions: operation, coordination, structure, and improvement. Ten sub-dimensions were followed. Each sub-dimension includes six to nineteen indicators for measuring radio program quality. In total, 72 indicators were identified. The AHP result revealed that the most important weight was given to the operation dimension. On the contrary, the least important weight was placed on the improvement dimension. Among the sub-dimensions, the standard procedure and organizational design were rated more important than the rest. The results could provide some facts to radio managers for future management.
基金supported by the Research Fund of Gaziantep University and the Scientific and Technological Research Council of Turkey (TUBITAK).
文摘The bound-state solution of the position dependent mass Klein-Gordon equation including inversely linear potential is obtained within the framework of the asymptotic iteration method. The relation between the scalar and vector potentials is considered to S(x) = V(x)(β - 1). In particular, it is shown that the corresponding method exactly reproduces the spectrum of linearly inversely potentials with spatially dependent mass.
基金We would like to thank Prof. Jia-Lun PING for helpful discussions.
文摘Using the coupled Dyson-Schwinger equation for the fermion propagator at finite chemical potential μ, we investigate the fermion chiral condensate when the gauge boson mass is nonzero in QED3. We show that the chiral symmetry restores when the boson mass is large enough, and the critical boson mass depends little on μ.
基金This research was supported by Research Fund of Southwest Forestry College (200510)
文摘The soil drought stress experiment in different durations (no watering within 3d, 6d, 9d, 11d individually) was conducted to study the drought-resistant capacity of one-year-old seedlings for the native tree species (Machilus yunnanensis) in Yunnan Province and the introduced tree species (Cinnamomum camphora). The leaf water potential, chlorophyll content, proline content and plasma membrane permeability for two species seedlings were measured in different soil drought conditions. The results showed that, on the 9th day of drought stress, the leaf water potential of two species decreased obviously, whereas the free proline content and plasma membrane permeability increased sharply. On the 11th day, the leaf water potential of C. camphora seedlings was lower than that of M. yunnanensis seedlings; the plasma membrane permeability in C. camphora seedling leaves increased much more than that in M. yunnanensis seedling leaves, which showed that the injury to the former by soil drought stress was more severe than that to the latter. The free proline content in M. yunnanensis seedling leaves continued to increase on the 11th day, but that in the C. camphora seedling leaves started to drop obviously, indicating that the reduction of osmotic regulation substance in C. camphora seedling leaves after the 11th day was unable to maintain the osmotic balance between the plasma system and its surroundings and the water loss occurred inevitably. Comprehensively, M. yunnanensis seedlings enhanced the drought-resistance in the course of soil drought stress by maintaining higher leaf water potential and by increasing osmotic regulation substance to promote cell plasma concentration and maintain membrane structure integrity so as to reduce water loss. The subordination function index evaluated with fuzzy mathematic theory also showed that the drought-resistant capacity of M. yunnanensis seedlings was stronger than that of C. camphora seedlings.
基金The project supported by National Natural Science Foundation of China under Grant Nos.10175093 and 10235030+4 种基金the Science Foundation of Chinese Nuclear Industry and the State Key Basic Research Development Program under Contract No.G20000774the Knowledge Innovation Project of the Chinese Academy of Sciences under Grant No.KJCX2-SW-N02the CASK.C.Wong Post-doctors Research Award Fund
文摘The N/Z ratio of free nucleons from collisions of neutron-rich nuclei as a function of their momentum is studied by means of isospin-dependent Quantum Molecular Dynamics. We find that this ratio is not only sensitive to the form of the density dependence of the symmetry potential energy but also its strength determined by the symmetry energy coefficient. The uncertainties about the symmetry energy coefficient influence the accuracy of probing the density dependence of the symmetry energy by means of the N/Z ratio of free nucleons of neutron-rich nuclei.
文摘With the rapid development of economy in our country, the level of science and technology innovation, all of these prolong the life span of our life. Thus an aging population are increasingly highlight, which are deeply and widely influenced our society, economy, life and other aspects. As the basic insurance which maintain the elderly's life quality after they retired, Pension insurance will promove social stability and development. How to reform Pension insurance under the background of the aging of the population will get more and more attention from people. This article starts with the concept of the aging of the population and its development trend. Next, the article analyses the problems of Pension Insurance under the background of the aging of the population. Last, the article summarizes countermeasures according to solve these matters.
基金supported by the National Natural Science Foundation of China (Grant No.10575082)the Natural Science Foundation of Gansu Province under Grant No.3ZS061-A25-014the Natural Science Foundation of Northwest Normal University under Grant No.NWNU-KJCXGC-03-17
文摘A (3+1 )-dimensional Kadomtse-Petviashvili (KP) equation for nonlinearly interacting intense laser pulses with an electron-positron (e-p) plasma is derived. Taking into account the combined action of the relativistic particle mass increase and the relativistic light ponderomotive force, using the perturbation method, and allowing different types solution, we discuss the analytical solution of (3+1)-dimensional KP-I equation, and give the approximate solutions of vector potential of the intense laser pulse in e-p plasma. Our results may be significantly useful in understanding the nonlinear wave propagation and interaction of intense laser beams in an e-p plasma.
文摘For the purpose of enhancing automobile safety and the effectiveness of recalls,increasing manufacturers' quality control capabilities,and reducing defects,we investigated thestatus of recalls over the last five years.We have examined patterns and trends in motor vehiclesafety recalls using databases from China,Europe and the United States.A recall rate parameterwas developed to evaluate the level of recall enforcement based on analyzing the reasonsfor recalls and manufactures' characteristics.Moreover,there were substantial differencesin the recall rates of China compared with those in other countries,indicating that Chinese manufacturersneed to take more active action in recall.
基金sponsored by the National Natural Science Foundation of China(Grant No.41206027)the China Postdoctoral Science Foundation(Grant No.2012M511460)+1 种基金the Key Laboratory of Global Change and Marine-Atmospheric Chemistry(Grant No.GCMAC1205)the Public Science and Technology Research Funds Projects of Ocean(Grant No.201105019)
文摘Here we used Empirical Mode Decomposition (EMD) method to study seasonal variability and nonlinear trend of corrected AERONET Aerosol Optical Depth (AOD/Hi) and corrected PM10 mass concentrations (PMmxf(RH)) in Hong Kong during 2005-2011. AODPrli is highly correlated with PMI0xf(RH) in semi-annual and annual time scales (with correlation coefficient 0.67 for semi-annual and 0.79 for annual components, 95% confidence interval). On the semi-annual scale, both AOD/Hi and PM10xf(RH) can capture the two maxima in March and October, respectively, with much stronger amplitude in March proba- bly due to the long-range transport of dust storm. On the annual cycle, the AOD/Hi and PMI0xf(RH), which are negatively correlated with the precipitation and solar radiation, vary coherently with the maxima in February. This annual peak occurs about one month earlier than the first peak of the semi-annual variability in March, but with only half amplitude. During 2005-2011, both AOD/Hi and PM10xf(RH) exhibit the pronounced decreasing trend with the mean rate of 14 gg m-3 per year for PM10xf(RH), which reflects the significant effects of the air pollution control policy in Hong Kong during the past decade. The nonlinear trend analysis indicates that the decreasing of PM10xf(RH) is slower than that of AOD/Hi when the AOD/Hi is less than 0.44 but becomes faster when the AOD/Hi exceeds 0.44. These results illustrate that the AERONET AOD can be used quantitatively to estimate local air-quality variability on the semi-annual, annual, and long-term trend time scales.
基金supported by the National Natural Science Foundation of China(51625202)the National Key Research&Development Program of China(2017YFB0701603)。
文摘Large roughness and structure disorder in ferroelectric ultrathin Langmuir-Blodgett(LB)film results in severe space scatter in electrical,ferroelectric and piezoelectric characteristics,thus limiting the nanoscale research and reliability of nano-devices.However,no effective method aiming at large-area uniform organic ferroelectric LB film has ever been reported to date.Herein,we present a facile hot-pressing strategy to prepare relatively large-area poly(vinylidene fluoride)(PVDF)LB film with ultra-smooth surface root mean square(RMS)roughness is 0.3 nm in a 30μm×30μm area comparable to that of metal substrate,which maximized the potential of LB technique to control thickness distribution.More importantly,compared with traditionally annealed LB film,the hot-pressed LB film manifests significantly improved structure uniformity,less fluctuation in ferroelectric characteristics and higher dielectric and piezoelectric responses,owing to the uniform dipole orientation and higher crystalline quality.Besides,different surface charge relaxation behaviors are investigated and the underlying mechanisms are explained in the light of the interplay of surface charge and polarization charge in the case of nanoscale non-uniform switching.We believe that our work not only presents a novel strategy to endow PVDF LB film with unprecedented reliability and improved performance as a competitive candidate for future ferroelectric tunnel junctions(FTJs)and nano electro mechanical systems(NEMS),but also reveals an attracting coupling effect between the surface potential distribution and nanoscale non-uniform switching behavior,which is crucial for the understanding of local transport characterization modulated by band structure,bit signal stability for data-storage application and the related surface charge research,such as charge gradient microscopy(CGM)based on the collection of surface charge on the biased ferroelectric domains.
基金Supported by the National Science Foundation of China(NSFC)under Grant Nos.11335001,11105153,11405178supported in part by the DFG and the NSFC(No.11261130311)through funds provided to the Sino-Germen CRC 110"Symmetries and the Emergence of Structure in QCD"performed on Tian He-1A supercomputer of the National Supercomputer Center in Tianjin
文摘Vector meson mass values are studied at finite chemical potential and temperature in lattice QCD with lattice size of 24 × 122× 6 using two flavors of staggered quarks. The investigation focuses on the change of the vector meson mass in the critical region close to T c with two different types of chemical potentials switched on: the isoscalar chemical potential μS and its isovector counterpart μV. It is found that the vector meson mass increases in the QGP phase with both chemical potentials and decreases with μS in the confinement phase.