美木属(Callixylon Zalessky,1911)是具有裸子植物解剖特征的茎干器官属,它主要产自晚泥盆世地层,仅个别可上延至下石炭统底部。迄今只在北半球发现,除两处产自高纬度外,其余均产自北纬35°-50°的狭长区域,其中以美国产地最多...美木属(Callixylon Zalessky,1911)是具有裸子植物解剖特征的茎干器官属,它主要产自晚泥盆世地层,仅个别可上延至下石炭统底部。迄今只在北半球发现,除两处产自高纬度外,其余均产自北纬35°-50°的狭长区域,其中以美国产地最多,次为苏联,北极加拿大、联邦德国、比利时和蒙古(Chaloner and Sheerin,1979;Lemoigne et al.,1983)、我国首次发现的美木属(蔡重阳,1986),产自新疆准噶尔盆地西北缘、和布克赛尔县城东南约30km的布龙果河西岸山坡上,地理位置大致为北纬45°,东经85°。展开更多
The ecological costs of open pit metal mining are quantified, which include lost value of direct eco-services, lost value of indirect eco-services, prevention and restoration costs, and cost of carbon emission from en...The ecological costs of open pit metal mining are quantified, which include lost value of direct eco-services, lost value of indirect eco-services, prevention and restoration costs, and cost of carbon emission from energy consumption. These ecological costs are incorporated in an iterative ultimate pit optimization algorithm. A case study is presented to demonstrate the influence of ecological costs on pit design outcome. The results show that it is possible to internalize ecological costs in mine designs. The pit optimization outcome shifts considerably to the conservative side and the profitability decreases substantially when ecological costs are accounted for.展开更多
Metal-core piezoelectric fibers (MPFs) are one of the new type piezoelectric devices. To investigate the piezoelectricity and the mechanical properties of the piezoelectric fibers, the constitutive equations are est...Metal-core piezoelectric fibers (MPFs) are one of the new type piezoelectric devices. To investigate the piezoelectricity and the mechanical properties of the piezoelectric fibers, the constitutive equations are established. It can describe the response of piezoelectric fibers subject to an axial force and an external voltage. A cantilever bar subject to a tip axial force and an external voltage on the electrodes is considered. The internal energy density in thermodynamic equilibrium is obtained. The total internal energy is calculated by integrating over the entire volume of the bar. The generalized displacement of the tip axial force is the tip elongation δ, and the generalized displacement of the voltage is the electrical charge Q on the electrodes. In the established constitutive equations, the excitation (input) parameters are the axial force and the external voltage, the response (output) parameters are the tip elongation and the electric charge. And the response parameters are related to the excitation parameters by a 2× 2 piezoelectric matrix. Finally, two experiments using MPF as a sensor or an actuator are performed to verify the constitutive equations. And experimental results are compared with analytical ones.展开更多
The hot deformation behaviors of 35%SiCp/2024 aluminum alloy composites were studied by hot compression tests using Gleeble-1500D thermo-mechanical simulator at temperatures ranging from 350 to 500 °C under strai...The hot deformation behaviors of 35%SiCp/2024 aluminum alloy composites were studied by hot compression tests using Gleeble-1500D thermo-mechanical simulator at temperatures ranging from 350 to 500 °C under strain rates of 0.01-10 s-1. The true stress-true strain curves were obtained in the tests. Constitutive equation and processing map were established. The results show that the flow stress decreases with the increase of deformation temperature at a constant strain rate, and increases with the increase of strain rate at constant temperature, indicating that composite is a positive strain rate sensitive material. The flow stress behavior of composite during hot compression deformation can be represented by a Zener-Hollomon parameter in the hyperbolic sine form. Its activation energy for hot deformation Q is 225.4 kJ/mol. To demonstrate the potential workability, the stable zones and the instability zones in the processing map were identified and verified through micrographs. Considering processing map and microstructure, the hot deformation should be carried out at the temperature of 500 °C and the strain rate of 0.1-1 s-1.展开更多
This paper is a part of revision of the subfamily Hylicinae. Two species of the genus Karasekia Melichar are redescribed and illustrated based on the types and additional specimens.The genus is described with the supp...This paper is a part of revision of the subfamily Hylicinae. Two species of the genus Karasekia Melichar are redescribed and illustrated based on the types and additional specimens.The genus is described with the supplement of male genital characteri-stics.展开更多
Low-temperature soluble carbohydrate accumulations are commonly associated with anthocyanin coloration, attenuated growth and cold adaptation of cool-season grasses. The vrn-1 gene has potent effects on vernalization ...Low-temperature soluble carbohydrate accumulations are commonly associated with anthocyanin coloration, attenuated growth and cold adaptation of cool-season grasses. The vrn-1 gene has potent effects on vernalization requirement, growth, and soluble carbohydrate accumulations of the winter-annual Triticeae species. Two hundred and four unmapped AFLP markers and genome-specific DNA markers genetically linked to the vrn-1 gene were used to detect QTL controlling soluble carbohydrate accumulations, anthocyanin coloration and growth characteristics in a segregating population derived from open pollinated Leymus cinereus x L. triticoides hybrids. These perennial Triticeae grasses are distinguished by adaptation and growth habit. As expected, positive trait correlations and pleiotropic gene effects were detected for soluble carbohydrate accumulations and anthocyanin coloration. Likewise, positive trait correlations and pleiotropic gene effects were detected for tillering, leaf development, leaf growth, regrowth and rhizome spread. However, soluble carbohydrate accumulations were not associated with attenuated growth. In fact, several DNA marker alleles, including one near vrn-Ns1, had positive effects on soluble leaf carbohydrate concentrations and low temperature growth. The corresponding DNA marker near vrn-Ns1 had more specific effects on tillering. We speculate that vrn-1 exerts quantitative effects on low-temperature soluble leaf carbohydrate accumulations and growth habit of the perennial Leymus. However, a number of other DNA markers displayed highly significant effects on soluble carbohydrate accumulations and various growth characteristics. Findings indicate that anthocyanin coloration may be a useful phenotypic marker for soluble carbohydrate accumulation. Although variation for soluble carbohydrates was not associated with attenuated growth in this population, this trait was under genetic control.展开更多
In order to improve the development step of bamboo industry, the pest investigation was done in Yunnan Province from 2000, and 1 500 specimens were collected. Basing on the investigation and the date of recordation, t...In order to improve the development step of bamboo industry, the pest investigation was done in Yunnan Province from 2000, and 1 500 specimens were collected. Basing on the investigation and the date of recordation, there had 224 species pests, belonging to 7 orders and 49 families. Among the pest, most done harm to the bamboo slightly, except Omphisa sp., Pantana phyllostachysae and Cyrtotrachelus buqueti. The disease and pest of bamboo should be investigated in whole province systematically.展开更多
The purpose of this work relates to study on the characteristics of ultra thin gate oxide (2 5nm thickness) and the effect of metal Al,Zr,and Ta contamination on GOI.The controlled metallic contamination experiments...The purpose of this work relates to study on the characteristics of ultra thin gate oxide (2 5nm thickness) and the effect of metal Al,Zr,and Ta contamination on GOI.The controlled metallic contamination experiments are carried out by depositing a few ppm contaminated metal and low pH solutions on the wafers.The maximum metal surface concentration is controlled at about 10 12 cm -2 level in order to simulate metal contamination during ultra clean processing.A ramped current stress for intrinsic charge to breakdown measurements with gate injection mode is used to examine the characteristics of these ultra thin gate oxides and the effect of metal contamination on GOI.It is the first time to investigate the influence of metal Zr and Ta contamination on 2 5nm ultra thin gate oxide.It is demonstrated that there is little effect of Al contamination on GOI,while Zr contamination is the most detrimental to GOI,and early breakdown has happened to wafers contaminated by Ta.展开更多
JOGMEC (Japan Oil, Gas and Metals National Corporation) has conducted exploration and research in Japan's EEZ (exclusive economic zone) from fiscal year 2008, under contract by the METI (Ministry of Economy, Tra...JOGMEC (Japan Oil, Gas and Metals National Corporation) has conducted exploration and research in Japan's EEZ (exclusive economic zone) from fiscal year 2008, under contract by the METI (Ministry of Economy, Trade and Industry), for the commercialization of SMS (Seafloor Massive Sulfide). As there is currently no commercial mining precedent of SMS, it is necessary to consider the potential impacts of mining on the surrounding environment, and to promote long term sustainable projects. In particular, due to the existence of specific chemosynthetic ecosystems and unique biological communities around the SMS area, both quantitative evaluations of potential environmental impacts and consequent environmental conservation strategies, are necessary in order to avoid and or minimize the potential detrimental effects to the ecosystem, as much as possible. The environmental research programs consist of baseline surveys, environmental impact modeling, and methodological concepts which will be applied to conserve biodiversity. In this paper, we will primarily provide an overview of the project conducted by JOGMEC during 2008-2012.展开更多
Inefficient charge separation and limited light absorption are two critical issues associated with high‐efficiency photocatalytic H2production using TiO2.Surface defects within a certain concentration range in photoc...Inefficient charge separation and limited light absorption are two critical issues associated with high‐efficiency photocatalytic H2production using TiO2.Surface defects within a certain concentration range in photocatalyst materials are beneficial for photocatalytic activity.In this study,surface defects(oxygen vacancies and metal cation replacement defects)were induced with a facile and effective approach by surface doping with low‐cost transition metals(Co,Ni,Cu,and Mn)on ultrafine TiO2.The obtained surface‐defective TiO2exhibited a3–4‐fold improved activity compared to that of the original ultrafine TiO2.In addition,a H2production rate of3.4μmol/h was obtained using visible light(λ>420nm)irradiation.The apparent quantum yield(AQY)at365nm reached36.9%over TiO2‐Cu,significantly more than the commercial P25TiO2.The enhancement of photocatalytic H2production activity can be attributed to improved rapid charge separation efficiency andexpanded light absorption window.This hydrothermal treatment with transition metal was proven to be a very facile and effective method for obtaining surface defects.展开更多
The role played by the functional groups of Laminaria japonica treated by methanol and formaldehyde in biosorption of the heavy metals was investigated. Infrared spectroscopy analysis and biosorption experiments show ...The role played by the functional groups of Laminaria japonica treated by methanol and formaldehyde in biosorption of the heavy metals was investigated. Infrared spectroscopy analysis and biosorption experiments show that both carboxyl and amino groups join in the sorption; chemical treatment decreased the biosorption efficiency of the heavy metals.展开更多
Lead is an important toxic heavy metal among environment pollution. Some industrial parks were founded in 2005 including non-ferrous metal processing and smelting plants. In order to identify the consequence of lead p...Lead is an important toxic heavy metal among environment pollution. Some industrial parks were founded in 2005 including non-ferrous metal processing and smelting plants. In order to identify the consequence of lead pollution on children around the industry park, blood samples of neighboring children were collected and analyzed in laboratory. The results showed that the involved children have suffered serious harms from Pb pollution. Almost 75% of the children's blood lead levels (BLLs) exceeded the limit of normal blood lead. Worse still, 26.17% of them were at the level of Moderate lead poisoning. The group aged 0-7 showed more susceptibility to Pb than that aged 8-14. Only 19.05% of the children aged 0-7 were at the level of normal blood lead, compared with 45.45% in the group aged 8-14. There was no significant difference between the values of blood lead concentration for male and female or among different age groups. Some approaches, which include controlling the Pb pollution from the industry park and safeguarding the residents, esp. the children were suggested.展开更多
The purpose of this article is to analyze the impact of corporate governance and disclosure policy on corporate financial performance by examining the combined effect of board characteristics and disclosure level on f...The purpose of this article is to analyze the impact of corporate governance and disclosure policy on corporate financial performance by examining the combined effect of board characteristics and disclosure level on financing costs. The empirical analysis, conducted on a sample of 192 Canadian companies, generally shows the importance of board characteristics in determining the level of disclosure and firms' costs of financing. In particular, the results found indicate that boards whose characteristics meet the governance requirements that are associated with greater transparency in disclosure on governance attributes reduce the costs of financing of their companies by debt as well as by equity capital.展开更多
In most existing CP-ABE schemes, there is only one authority in the system and all the public keys and private keys are issued by this authority, which incurs ciphertext size and computation costs in the encryption an...In most existing CP-ABE schemes, there is only one authority in the system and all the public keys and private keys are issued by this authority, which incurs ciphertext size and computation costs in the encryption and decryption operations that depend at least linearly on the number of attributes involved in the access policy. We propose an efficient multi-authority CP-ABE scheme in which the authorities need not interact to generate public information during the system initialization phase. Our scheme has constant ciphertext length and a constant number of pairing computations. Our scheme can be proven CPA-secure in random oracle model under the decision q-BDHE assumption. When user's attributes revocation occurs, the scheme transfers most re-encryption work to the cloud service provider, reducing the data owner's computational cost on the premise of security. Finally the analysis and simulation result show that the schemes proposed in this thesis ensure the privacy and secure access of sensitive data stored in the cloud server, and be able to cope with the dynamic changes of users' access privileges in large-scale systems. Besides, the multi-authority ABE eliminates the key escrow problem, achieves the length of ciphertext optimization and enhances the effi ciency of the encryption and decryption operations.展开更多
The monotypic genus Phycocaris Kemp, 1916, which was established based on material from the Indian Ocean and previously only known from the type localities, Australia and Japan, is now newly recorded from the South Ch...The monotypic genus Phycocaris Kemp, 1916, which was established based on material from the Indian Ocean and previously only known from the type localities, Australia and Japan, is now newly recorded from the South China Sea. A detailed description of Phycocaris simulans Kemp, 1916 based on the specimen collected from Hainan Island is presented. Specific features and the differences between the Indian Ocean and the present material are described.展开更多
Soil type maps at the scale of I Z 1 000 000 are used extensively to provide soil spatial distribution information for soil erosion assessment and watershed management models in China. However, the soil property maps ...Soil type maps at the scale of I Z 1 000 000 are used extensively to provide soil spatial distribution information for soil erosion assessment and watershed management models in China. However, the soil property maps produced through conventional direct linking method usually suffer low accuracy as well as the lack of spatial details within a soil type polygon. This paper presents an effective method to produce detailed soil property map based on representative samples which were extracted from each polygon on the 1 : 1 000 000 soil type map. The representative sample of each polygon is defined as the location that can represent the largest area within the polygon. The representativeness of a candidate sample is determined by calculating the soil-forming environment condition similarities between the sample and other locations. Once the representative sample of each polygon has been chosen, the property values of the existing typical samples are assigned to the corresponding representative samples with the same soil type. Finally, based on these representative samples, the detailed soil property map could be produced by using existing digital soil mapping methods. The case study in XuanCheng City, Anhui Province of China, demonstrated the proposed method could produce soil property map at a higher level of spatial details and accuracy: 1) The soil organic matter (SOM) map produced based on the representative samples can not only depict the detailed spatial distribution of SOM within a soil type polygon but also largely reduce the abrupt change of soil property at the boundaries of two adjacent polygons. 2) The Root Mean Squared Error (RMSE) of the SOM map based on the representative samples is 1.61, and it is 1.37 for the SOM map produced by using conventional direct linking method. Therefore, the proposed method is an effective approach to produce spatial detailed soil property map with higher accuracy for environment simulation models.展开更多
The marine area of Japan, including territorial waters and the exclusive economic zone, is the sixth largest in the world at about 4,470,000 km2. Therefore, it is becoming necessary to establish appropriate means of t...The marine area of Japan, including territorial waters and the exclusive economic zone, is the sixth largest in the world at about 4,470,000 km2. Therefore, it is becoming necessary to establish appropriate means of transportation other than ships in order to utilize the area efficiently. In this respect, ultra-light seaplanes are attracting attention from the viewpoint of protecting the natural environment. Accordingly, JRPS (Japan Reinforced Plastics Society) is currently developing FRP (fiber-reinforced plastic) floats for such planes. In this study, we conducted simulations of seaplane behavior during alighting by using the smoothed particle hydrodynamics method, which is one of the functions in the PAM-CRASH solver, and we present the observed trend in the vertical acceleration of the floats as a first step toward deriving the impact force from analytical data.展开更多
文摘美木属(Callixylon Zalessky,1911)是具有裸子植物解剖特征的茎干器官属,它主要产自晚泥盆世地层,仅个别可上延至下石炭统底部。迄今只在北半球发现,除两处产自高纬度外,其余均产自北纬35°-50°的狭长区域,其中以美国产地最多,次为苏联,北极加拿大、联邦德国、比利时和蒙古(Chaloner and Sheerin,1979;Lemoigne et al.,1983)、我国首次发现的美木属(蔡重阳,1986),产自新疆准噶尔盆地西北缘、和布克赛尔县城东南约30km的布龙果河西岸山坡上,地理位置大致为北纬45°,东经85°。
基金Project(50974041)supported by the National Natural Science Foundation of ChinaProject(NCET-11-0073)supported by Program for New Century Excellent Talents in University of Ministry of Education of China+1 种基金Project(201102065)supported by the Natural Science Foundation of Liaoning Province,ChinaProject(2012921075)supported by the Ten Million Talent Project of Liaoning Province,China
文摘The ecological costs of open pit metal mining are quantified, which include lost value of direct eco-services, lost value of indirect eco-services, prevention and restoration costs, and cost of carbon emission from energy consumption. These ecological costs are incorporated in an iterative ultimate pit optimization algorithm. A case study is presented to demonstrate the influence of ecological costs on pit design outcome. The results show that it is possible to internalize ecological costs in mine designs. The pit optimization outcome shifts considerably to the conservative side and the profitability decreases substantially when ecological costs are accounted for.
基金the National High Technology Research and Development Program of China(863Pro-gram)(2007AA03Z104)~~
文摘Metal-core piezoelectric fibers (MPFs) are one of the new type piezoelectric devices. To investigate the piezoelectricity and the mechanical properties of the piezoelectric fibers, the constitutive equations are established. It can describe the response of piezoelectric fibers subject to an axial force and an external voltage. A cantilever bar subject to a tip axial force and an external voltage on the electrodes is considered. The internal energy density in thermodynamic equilibrium is obtained. The total internal energy is calculated by integrating over the entire volume of the bar. The generalized displacement of the tip axial force is the tip elongation δ, and the generalized displacement of the voltage is the electrical charge Q on the electrodes. In the established constitutive equations, the excitation (input) parameters are the axial force and the external voltage, the response (output) parameters are the tip elongation and the electric charge. And the response parameters are related to the excitation parameters by a 2× 2 piezoelectric matrix. Finally, two experiments using MPF as a sensor or an actuator are performed to verify the constitutive equations. And experimental results are compared with analytical ones.
基金Project(51371077)supported by the National Natural Science Foundation of China
文摘The hot deformation behaviors of 35%SiCp/2024 aluminum alloy composites were studied by hot compression tests using Gleeble-1500D thermo-mechanical simulator at temperatures ranging from 350 to 500 °C under strain rates of 0.01-10 s-1. The true stress-true strain curves were obtained in the tests. Constitutive equation and processing map were established. The results show that the flow stress decreases with the increase of deformation temperature at a constant strain rate, and increases with the increase of strain rate at constant temperature, indicating that composite is a positive strain rate sensitive material. The flow stress behavior of composite during hot compression deformation can be represented by a Zener-Hollomon parameter in the hyperbolic sine form. Its activation energy for hot deformation Q is 225.4 kJ/mol. To demonstrate the potential workability, the stable zones and the instability zones in the processing map were identified and verified through micrographs. Considering processing map and microstructure, the hot deformation should be carried out at the temperature of 500 °C and the strain rate of 0.1-1 s-1.
基金the National Science Foundation of China(grant no.3 92 70 1 1 6 )
文摘This paper is a part of revision of the subfamily Hylicinae. Two species of the genus Karasekia Melichar are redescribed and illustrated based on the types and additional specimens.The genus is described with the supplement of male genital characteri-stics.
文摘Low-temperature soluble carbohydrate accumulations are commonly associated with anthocyanin coloration, attenuated growth and cold adaptation of cool-season grasses. The vrn-1 gene has potent effects on vernalization requirement, growth, and soluble carbohydrate accumulations of the winter-annual Triticeae species. Two hundred and four unmapped AFLP markers and genome-specific DNA markers genetically linked to the vrn-1 gene were used to detect QTL controlling soluble carbohydrate accumulations, anthocyanin coloration and growth characteristics in a segregating population derived from open pollinated Leymus cinereus x L. triticoides hybrids. These perennial Triticeae grasses are distinguished by adaptation and growth habit. As expected, positive trait correlations and pleiotropic gene effects were detected for soluble carbohydrate accumulations and anthocyanin coloration. Likewise, positive trait correlations and pleiotropic gene effects were detected for tillering, leaf development, leaf growth, regrowth and rhizome spread. However, soluble carbohydrate accumulations were not associated with attenuated growth. In fact, several DNA marker alleles, including one near vrn-Ns1, had positive effects on soluble leaf carbohydrate concentrations and low temperature growth. The corresponding DNA marker near vrn-Ns1 had more specific effects on tillering. We speculate that vrn-1 exerts quantitative effects on low-temperature soluble leaf carbohydrate accumulations and growth habit of the perennial Leymus. However, a number of other DNA markers displayed highly significant effects on soluble carbohydrate accumulations and various growth characteristics. Findings indicate that anthocyanin coloration may be a useful phenotypic marker for soluble carbohydrate accumulation. Although variation for soluble carbohydrates was not associated with attenuated growth in this population, this trait was under genetic control.
基金Supported by Key Technologies R&D Programme of the Ministry of Science and Technology of the People’s Republic of China during the Eleventh Five-year Plan(2006BAD19B09)~~
文摘In order to improve the development step of bamboo industry, the pest investigation was done in Yunnan Province from 2000, and 1 500 specimens were collected. Basing on the investigation and the date of recordation, there had 224 species pests, belonging to 7 orders and 49 families. Among the pest, most done harm to the bamboo slightly, except Omphisa sp., Pantana phyllostachysae and Cyrtotrachelus buqueti. The disease and pest of bamboo should be investigated in whole province systematically.
文摘The purpose of this work relates to study on the characteristics of ultra thin gate oxide (2 5nm thickness) and the effect of metal Al,Zr,and Ta contamination on GOI.The controlled metallic contamination experiments are carried out by depositing a few ppm contaminated metal and low pH solutions on the wafers.The maximum metal surface concentration is controlled at about 10 12 cm -2 level in order to simulate metal contamination during ultra clean processing.A ramped current stress for intrinsic charge to breakdown measurements with gate injection mode is used to examine the characteristics of these ultra thin gate oxides and the effect of metal contamination on GOI.It is the first time to investigate the influence of metal Zr and Ta contamination on 2 5nm ultra thin gate oxide.It is demonstrated that there is little effect of Al contamination on GOI,while Zr contamination is the most detrimental to GOI,and early breakdown has happened to wafers contaminated by Ta.
文摘JOGMEC (Japan Oil, Gas and Metals National Corporation) has conducted exploration and research in Japan's EEZ (exclusive economic zone) from fiscal year 2008, under contract by the METI (Ministry of Economy, Trade and Industry), for the commercialization of SMS (Seafloor Massive Sulfide). As there is currently no commercial mining precedent of SMS, it is necessary to consider the potential impacts of mining on the surrounding environment, and to promote long term sustainable projects. In particular, due to the existence of specific chemosynthetic ecosystems and unique biological communities around the SMS area, both quantitative evaluations of potential environmental impacts and consequent environmental conservation strategies, are necessary in order to avoid and or minimize the potential detrimental effects to the ecosystem, as much as possible. The environmental research programs consist of baseline surveys, environmental impact modeling, and methodological concepts which will be applied to conserve biodiversity. In this paper, we will primarily provide an overview of the project conducted by JOGMEC during 2008-2012.
基金supported by the Double First‐rate Subject‐Food Science and Engineering Program of Hebei Province (2018SPGCA18)Young Tip‐top Talents Plan of Universities and Colleges in Hebei Province of China (BJ2017026)the Specific Foundation for Doctor in Hebei Agriculture University of China (ZD201709)~~
文摘Inefficient charge separation and limited light absorption are two critical issues associated with high‐efficiency photocatalytic H2production using TiO2.Surface defects within a certain concentration range in photocatalyst materials are beneficial for photocatalytic activity.In this study,surface defects(oxygen vacancies and metal cation replacement defects)were induced with a facile and effective approach by surface doping with low‐cost transition metals(Co,Ni,Cu,and Mn)on ultrafine TiO2.The obtained surface‐defective TiO2exhibited a3–4‐fold improved activity compared to that of the original ultrafine TiO2.In addition,a H2production rate of3.4μmol/h was obtained using visible light(λ>420nm)irradiation.The apparent quantum yield(AQY)at365nm reached36.9%over TiO2‐Cu,significantly more than the commercial P25TiO2.The enhancement of photocatalytic H2production activity can be attributed to improved rapid charge separation efficiency andexpanded light absorption window.This hydrothermal treatment with transition metal was proven to be a very facile and effective method for obtaining surface defects.
文摘The role played by the functional groups of Laminaria japonica treated by methanol and formaldehyde in biosorption of the heavy metals was investigated. Infrared spectroscopy analysis and biosorption experiments show that both carboxyl and amino groups join in the sorption; chemical treatment decreased the biosorption efficiency of the heavy metals.
文摘Lead is an important toxic heavy metal among environment pollution. Some industrial parks were founded in 2005 including non-ferrous metal processing and smelting plants. In order to identify the consequence of lead pollution on children around the industry park, blood samples of neighboring children were collected and analyzed in laboratory. The results showed that the involved children have suffered serious harms from Pb pollution. Almost 75% of the children's blood lead levels (BLLs) exceeded the limit of normal blood lead. Worse still, 26.17% of them were at the level of Moderate lead poisoning. The group aged 0-7 showed more susceptibility to Pb than that aged 8-14. Only 19.05% of the children aged 0-7 were at the level of normal blood lead, compared with 45.45% in the group aged 8-14. There was no significant difference between the values of blood lead concentration for male and female or among different age groups. Some approaches, which include controlling the Pb pollution from the industry park and safeguarding the residents, esp. the children were suggested.
文摘The purpose of this article is to analyze the impact of corporate governance and disclosure policy on corporate financial performance by examining the combined effect of board characteristics and disclosure level on financing costs. The empirical analysis, conducted on a sample of 192 Canadian companies, generally shows the importance of board characteristics in determining the level of disclosure and firms' costs of financing. In particular, the results found indicate that boards whose characteristics meet the governance requirements that are associated with greater transparency in disclosure on governance attributes reduce the costs of financing of their companies by debt as well as by equity capital.
基金supported by National Natural Science Foundation of China under Grant No.60873231Natural Science Foundation of Jiangsu Province under Grant No.BK2009426+1 种基金Major State Basic Research Development Program of China under Grant No.2011CB302903Key University Science Research Project of Jiangsu Province under Grant No.11KJA520002
文摘In most existing CP-ABE schemes, there is only one authority in the system and all the public keys and private keys are issued by this authority, which incurs ciphertext size and computation costs in the encryption and decryption operations that depend at least linearly on the number of attributes involved in the access policy. We propose an efficient multi-authority CP-ABE scheme in which the authorities need not interact to generate public information during the system initialization phase. Our scheme has constant ciphertext length and a constant number of pairing computations. Our scheme can be proven CPA-secure in random oracle model under the decision q-BDHE assumption. When user's attributes revocation occurs, the scheme transfers most re-encryption work to the cloud service provider, reducing the data owner's computational cost on the premise of security. Finally the analysis and simulation result show that the schemes proposed in this thesis ensure the privacy and secure access of sensitive data stored in the cloud server, and be able to cope with the dynamic changes of users' access privileges in large-scale systems. Besides, the multi-authority ABE eliminates the key escrow problem, achieves the length of ciphertext optimization and enhances the effi ciency of the encryption and decryption operations.
基金Supported by the Marine Public Welfare Project of China Program(No.201505004)the National Natural Science Foundation of China(Nos.41506171,41376163)
文摘The monotypic genus Phycocaris Kemp, 1916, which was established based on material from the Indian Ocean and previously only known from the type localities, Australia and Japan, is now newly recorded from the South China Sea. A detailed description of Phycocaris simulans Kemp, 1916 based on the specimen collected from Hainan Island is presented. Specific features and the differences between the Indian Ocean and the present material are described.
基金Under the auspices of Program of International Science & Technology Cooperation,Ministry of Science and Technology of China(No.2010DFB24140)National Natural Science Foundation of China(No.41023010,41001298)National High Technology Research and Development Program of China(No.2011AA120305)
文摘Soil type maps at the scale of I Z 1 000 000 are used extensively to provide soil spatial distribution information for soil erosion assessment and watershed management models in China. However, the soil property maps produced through conventional direct linking method usually suffer low accuracy as well as the lack of spatial details within a soil type polygon. This paper presents an effective method to produce detailed soil property map based on representative samples which were extracted from each polygon on the 1 : 1 000 000 soil type map. The representative sample of each polygon is defined as the location that can represent the largest area within the polygon. The representativeness of a candidate sample is determined by calculating the soil-forming environment condition similarities between the sample and other locations. Once the representative sample of each polygon has been chosen, the property values of the existing typical samples are assigned to the corresponding representative samples with the same soil type. Finally, based on these representative samples, the detailed soil property map could be produced by using existing digital soil mapping methods. The case study in XuanCheng City, Anhui Province of China, demonstrated the proposed method could produce soil property map at a higher level of spatial details and accuracy: 1) The soil organic matter (SOM) map produced based on the representative samples can not only depict the detailed spatial distribution of SOM within a soil type polygon but also largely reduce the abrupt change of soil property at the boundaries of two adjacent polygons. 2) The Root Mean Squared Error (RMSE) of the SOM map based on the representative samples is 1.61, and it is 1.37 for the SOM map produced by using conventional direct linking method. Therefore, the proposed method is an effective approach to produce spatial detailed soil property map with higher accuracy for environment simulation models.
文摘The marine area of Japan, including territorial waters and the exclusive economic zone, is the sixth largest in the world at about 4,470,000 km2. Therefore, it is becoming necessary to establish appropriate means of transportation other than ships in order to utilize the area efficiently. In this respect, ultra-light seaplanes are attracting attention from the viewpoint of protecting the natural environment. Accordingly, JRPS (Japan Reinforced Plastics Society) is currently developing FRP (fiber-reinforced plastic) floats for such planes. In this study, we conducted simulations of seaplane behavior during alighting by using the smoothed particle hydrodynamics method, which is one of the functions in the PAM-CRASH solver, and we present the observed trend in the vertical acceleration of the floats as a first step toward deriving the impact force from analytical data.