In this paper, we present the analytical expressions for computing the minimum distance between a point and a torus, which is called the orthogonal projection point problem. If the test point is on the outside of the ...In this paper, we present the analytical expressions for computing the minimum distance between a point and a torus, which is called the orthogonal projection point problem. If the test point is on the outside of the torus and the test point is at the center axis of the torus, we present that the orthogonal projection point set is a circle perpendicular to the center axis of the torus;if not, the analytical expression for the orthogonal projection point problem is also given. Furthermore, if the test point is in the inside of the torus, we also give the corresponding analytical expression for orthogonal projection point for two cases.展开更多
An improved analytical method to determine the content of 52 major, minor and trace elements in marine geological samples, using a HF-HCl-HNO_3 acid system with a high-pressure closed digestion method(HPCD), is stud...An improved analytical method to determine the content of 52 major, minor and trace elements in marine geological samples, using a HF-HCl-HNO_3 acid system with a high-pressure closed digestion method(HPCD), is studied by an inductively coupled plasma optical emission spectrometry(ICP-OES) and an inductively coupled plasma mass spectrometry(ICP-MS). The operating parameters of the instruments are optimized, and the optimal analytical parameters are determined. The influences of optical spectrum and mass spectrum interferences, digestion methods and acid systems on the analytical results are investigated. The optimal spectral lines and isotopes are chosen, and internal standard element of rhodium is selected to compensate for matrix effects and analytical signals drifting. Compared with the methods of an electric heating plate digestion and a microwave digestion, a high-pressure closed digestion method is optimized with less acid, complete digestion,less damage for digestion process. The marine geological samples are dissolved completely by a HF-HCl-HNO_3 system, the relative error(RE) for the analytical results are all less than 6.0%. The method detection limits are 2–40μg/g by the ICP-OES, and 6–80 ng/g by ICP-MS. The methods are used to determine the marine sediment reference materials(GBW07309, GBW07311, GBW07313), rock reference materials(GBW07103, GBW07104,GBW07105), and cobalt-rich crust reference materials(GBW07337, GBW07338, GBW07339), the obtained analytical results are in agreement with the certified values, and both of the relative standard deviation(RSD) and the relative error(RE) are less than 6.0%. The analytical method meets the requirements for determining 52 elements contents of bulk marine geological samples.展开更多
Inheritance of line Jinghe891-l resistant to pathotype of Puccinia striiformis in two patterns of temperature (Normal: day 18℃ /night 10℃ , High: day 24℃ /night 15℃ )was studied in this paper. The results showed t...Inheritance of line Jinghe891-l resistant to pathotype of Puccinia striiformis in two patterns of temperature (Normal: day 18℃ /night 10℃ , High: day 24℃ /night 15℃ )was studied in this paper. The results showed that there were at least two pairs of dominant major genes and one pair of recessive minor genes in Jinghe 891-1. The two pairs of major genes that conferred resistance to CY31 were allelic or linked closely with resistance gene in Jubilejna Ⅱ , Kangyin655 and T. spelta Album. They were novel resistance genes and were inherited in a repeated or independent mode. The minor genes, which could modify the major genes, were sensitive to temperature and conferred resistance to all pathotypes of Puccinia striiformis in China. It is recommended that this line can be used as an important resource stock.展开更多
The electric gating on the transport properties of two-dimensional electron gas(2DEG) at the interface of LaAlO_(3)/SrTiO_(3)(LAO/STO) heterostructure has attracted great research interest due to its potential applica...The electric gating on the transport properties of two-dimensional electron gas(2DEG) at the interface of LaAlO_(3)/SrTiO_(3)(LAO/STO) heterostructure has attracted great research interest due to its potential application in fieldeffect devices. Most of previous works of gate effect were focused on the LAO/STO heterostructure containing only one conductive interface. Here, we systematically investigated the gate effect on high-quality LAO/STO superlattices(SLs)fabricated on the TiO_(2)-terminated(001) STO substrates. In addition to the good metallicity of all SLs, we found that there are two types of charge carriers, the majority carriers and the minority carriers, coexisting in the SLs. The sheet resistance of the SLs with a fixed thickness of the LAO layer increases monotonically as the thickness of the STO layer increases. This is derived from the dependence of the minority carrier density on the thickness of STO. Unlike the LAO/STO heterostructure in which minority and majority carriers are simultaneously modulated by the gate effect, the minority carriers in the SLs can be tuned more significantly by the electric gating while the density of majority carriers is almost invariable. Thus, we consider that the minority carriers may mainly exist in the first interface near the STO substrate that is more sensitive to the back-gate voltage, and the majority carriers exist in the post-deposited STO layers. The SL structure provides the space separation for the multichannel conduction in the 2 DEG, which opens an avenue for the design of field-effect devices based on LAO/STO heterostructure.展开更多
In recent years,due to the impact of university increase enrollment policy,the slowdown of global economic growth and other factors,the Students face employment pressure has become a general social problem.And minorit...In recent years,due to the impact of university increase enrollment policy,the slowdown of global economic growth and other factors,the Students face employment pressure has become a general social problem.And minority university students have a huge disadvantage in employment direction compared with the other ordinary university students.Exploring the ways of minority university students'employability and major selection capability are helpful to find targeted solutions and it has impor tant practical value.展开更多
The paper proposes the conception of Beads type fold system. The mechanical analyses of the typical tectonic system are made by means of elastic stability theory, mathematical and mechanical method and rheology. The...The paper proposes the conception of Beads type fold system. The mechanical analyses of the typical tectonic system are made by means of elastic stability theory, mathematical and mechanical method and rheology. The relation among the deflections of folds and time, external forces, and distribution of stresses, strain energy density are analyzed to explain the causing mechanism of folding earthquake.展开更多
This paper analyzes the English learning motivation of minority students of non-English major.Minority students are a unique community in the higher vocational school because of their special background and psychology...This paper analyzes the English learning motivation of minority students of non-English major.Minority students are a unique community in the higher vocational school because of their special background and psychology.It is essential for teachers to understand their motivation of learning English so as to save time and teach more efficiently.展开更多
In this paper we introduce a new general subclass n,G∑ a,λ(A, B, α) of univalent functions related the known integral operator and differential operator. Some majorization results for n,G∑ a,λ(A, B, 1) as well as...In this paper we introduce a new general subclass n,G∑ a,λ(A, B, α) of univalent functions related the known integral operator and differential operator. Some majorization results for n,G∑ a,λ(A, B, 1) as well as the other functions are given. Furthermore, we find the coefficients bounds on |a_2| and |a_3| for functions in*n,G∑ a,λ(A_1, B_1, A_2, B_2, α_1, α_2), which is the bi-univalent functions defined by n,G ∑a,λ(A, B, α) and subordination. By giving specific values of the parameters of our main results, several(known or new) consequences of main results are also discussed.展开更多
The continuum approach in fluid flow modeling is generally applied to porous geological media, but has limited applicability to fractured rocks. With the presence of a discrete fracture network relatively sparsely dis...The continuum approach in fluid flow modeling is generally applied to porous geological media, but has limited applicability to fractured rocks. With the presence of a discrete fracture network relatively sparsely distributed in the matrix, it may be difficult or erroneous to use a porous medium fluid flow model with continuum assumptions to describe the fluid flow in fractured rocks at small or even large field scales. A discrete fracture fluid flow approach incorporating a stochastic fracture network with numerical fluid flow simulations could have the capability of capturing fluid flow behaviors such as inhomogeneity and anisotropy while reflecting the changes of hydraulic features at different scales. Moreover, this approach can be implemented to estimate the size of the representative elementary volume (REV) in order to find out the scales at which a porous medium flow model could be applied, and then to determine the hydraulic conductivity tensor for fractured rocks. The following topics are focused on in this study: (a) conceptual discrete fracture fluid flow modeling incorporating a stochastic fracture network with numerical flow simulations; (b) estimation of REV and hydraulic conductivity tensor for fractured rocks utilizing a stochastic fracture network with numerical fluid flow simulations; (c) investigation of the effect of fracture orientation and density on the hydraulic conductivity and REV by implementing a stochastic fracture network with numerical fluid flow simulations, and (d) fluid flow conceptual models accounting for major and minor fractures in the 2 D or 3 D flow fields incorporating a stochastic fracture network with numerical fluid flow simulations.展开更多
Context Theory have been extensively used in the teaching of minority English majors. Meanwhile, teachers of English in China have been inevitably involved in language testing of various types, either to choose an app...Context Theory have been extensively used in the teaching of minority English majors. Meanwhile, teachers of English in China have been inevitably involved in language testing of various types, either to choose an appropriate existing language test or design by themselves. Therefore it is of practical significance to testify whether the course taken under the Context Theory has enabled teachers to become competent in the design, development, and use of language tests. The main purpose of the present study is to analyze the quality of English grammar paper to check whether minority English majors' management of English grammar have been improved.展开更多
文摘In this paper, we present the analytical expressions for computing the minimum distance between a point and a torus, which is called the orthogonal projection point problem. If the test point is on the outside of the torus and the test point is at the center axis of the torus, we present that the orthogonal projection point set is a circle perpendicular to the center axis of the torus;if not, the analytical expression for the orthogonal projection point problem is also given. Furthermore, if the test point is in the inside of the torus, we also give the corresponding analytical expression for orthogonal projection point for two cases.
基金The China Ocean Mineral Resources Research and Development Association Research Program of the State Oceanic Administration of China under contract No.DY125-13-R-07the National Natural Science Foundation of China under contract Nos 41322036 and 41230960+1 种基金the Shandong Provincial Natural Science Foundation of China under contract No.ZR2014DP009the Special Basic Research Funds for Central Public Research Institutes for The First Institute of Oceanography,State Oceanic Administration of China under contract Nos GY0213G06 and GY02-2012G35
文摘An improved analytical method to determine the content of 52 major, minor and trace elements in marine geological samples, using a HF-HCl-HNO_3 acid system with a high-pressure closed digestion method(HPCD), is studied by an inductively coupled plasma optical emission spectrometry(ICP-OES) and an inductively coupled plasma mass spectrometry(ICP-MS). The operating parameters of the instruments are optimized, and the optimal analytical parameters are determined. The influences of optical spectrum and mass spectrum interferences, digestion methods and acid systems on the analytical results are investigated. The optimal spectral lines and isotopes are chosen, and internal standard element of rhodium is selected to compensate for matrix effects and analytical signals drifting. Compared with the methods of an electric heating plate digestion and a microwave digestion, a high-pressure closed digestion method is optimized with less acid, complete digestion,less damage for digestion process. The marine geological samples are dissolved completely by a HF-HCl-HNO_3 system, the relative error(RE) for the analytical results are all less than 6.0%. The method detection limits are 2–40μg/g by the ICP-OES, and 6–80 ng/g by ICP-MS. The methods are used to determine the marine sediment reference materials(GBW07309, GBW07311, GBW07313), rock reference materials(GBW07103, GBW07104,GBW07105), and cobalt-rich crust reference materials(GBW07337, GBW07338, GBW07339), the obtained analytical results are in agreement with the certified values, and both of the relative standard deviation(RSD) and the relative error(RE) are less than 6.0%. The analytical method meets the requirements for determining 52 elements contents of bulk marine geological samples.
基金supported by the Beijing Natural Science Foundation(6962006).
文摘Inheritance of line Jinghe891-l resistant to pathotype of Puccinia striiformis in two patterns of temperature (Normal: day 18℃ /night 10℃ , High: day 24℃ /night 15℃ )was studied in this paper. The results showed that there were at least two pairs of dominant major genes and one pair of recessive minor genes in Jinghe 891-1. The two pairs of major genes that conferred resistance to CY31 were allelic or linked closely with resistance gene in Jubilejna Ⅱ , Kangyin655 and T. spelta Album. They were novel resistance genes and were inherited in a repeated or independent mode. The minor genes, which could modify the major genes, were sensitive to temperature and conferred resistance to all pathotypes of Puccinia striiformis in China. It is recommended that this line can be used as an important resource stock.
基金Project supported by the National Basic Research Program of China(Grant Nos.2016YFA0300701,2017YFA0206300,2017YFA0303601,and2018YFA0305704)the National Natural Science Foundation of China(Grant Nos.11520101002,51590880,11674378,11934016,and 51972335)the Key Program of the Chinese Academy of Sciences。
文摘The electric gating on the transport properties of two-dimensional electron gas(2DEG) at the interface of LaAlO_(3)/SrTiO_(3)(LAO/STO) heterostructure has attracted great research interest due to its potential application in fieldeffect devices. Most of previous works of gate effect were focused on the LAO/STO heterostructure containing only one conductive interface. Here, we systematically investigated the gate effect on high-quality LAO/STO superlattices(SLs)fabricated on the TiO_(2)-terminated(001) STO substrates. In addition to the good metallicity of all SLs, we found that there are two types of charge carriers, the majority carriers and the minority carriers, coexisting in the SLs. The sheet resistance of the SLs with a fixed thickness of the LAO layer increases monotonically as the thickness of the STO layer increases. This is derived from the dependence of the minority carrier density on the thickness of STO. Unlike the LAO/STO heterostructure in which minority and majority carriers are simultaneously modulated by the gate effect, the minority carriers in the SLs can be tuned more significantly by the electric gating while the density of majority carriers is almost invariable. Thus, we consider that the minority carriers may mainly exist in the first interface near the STO substrate that is more sensitive to the back-gate voltage, and the majority carriers exist in the post-deposited STO layers. The SL structure provides the space separation for the multichannel conduction in the 2 DEG, which opens an avenue for the design of field-effect devices based on LAO/STO heterostructure.
文摘In recent years,due to the impact of university increase enrollment policy,the slowdown of global economic growth and other factors,the Students face employment pressure has become a general social problem.And minority university students have a huge disadvantage in employment direction compared with the other ordinary university students.Exploring the ways of minority university students'employability and major selection capability are helpful to find targeted solutions and it has impor tant practical value.
文摘The paper proposes the conception of Beads type fold system. The mechanical analyses of the typical tectonic system are made by means of elastic stability theory, mathematical and mechanical method and rheology. The relation among the deflections of folds and time, external forces, and distribution of stresses, strain energy density are analyzed to explain the causing mechanism of folding earthquake.
文摘This paper analyzes the English learning motivation of minority students of non-English major.Minority students are a unique community in the higher vocational school because of their special background and psychology.It is essential for teachers to understand their motivation of learning English so as to save time and teach more efficiently.
基金Supported by the Scientific Research Found of Education Department of Sichuan Province(14ZB0364)
文摘In this paper we introduce a new general subclass n,G∑ a,λ(A, B, α) of univalent functions related the known integral operator and differential operator. Some majorization results for n,G∑ a,λ(A, B, 1) as well as the other functions are given. Furthermore, we find the coefficients bounds on |a_2| and |a_3| for functions in*n,G∑ a,λ(A_1, B_1, A_2, B_2, α_1, α_2), which is the bi-univalent functions defined by n,G ∑a,λ(A, B, α) and subordination. By giving specific values of the parameters of our main results, several(known or new) consequences of main results are also discussed.
基金ChinaCommitteeofEducation theUniver sityofArizonaandtheMetropolitanWaterDistrictofSouthernCaliforni a.
文摘The continuum approach in fluid flow modeling is generally applied to porous geological media, but has limited applicability to fractured rocks. With the presence of a discrete fracture network relatively sparsely distributed in the matrix, it may be difficult or erroneous to use a porous medium fluid flow model with continuum assumptions to describe the fluid flow in fractured rocks at small or even large field scales. A discrete fracture fluid flow approach incorporating a stochastic fracture network with numerical fluid flow simulations could have the capability of capturing fluid flow behaviors such as inhomogeneity and anisotropy while reflecting the changes of hydraulic features at different scales. Moreover, this approach can be implemented to estimate the size of the representative elementary volume (REV) in order to find out the scales at which a porous medium flow model could be applied, and then to determine the hydraulic conductivity tensor for fractured rocks. The following topics are focused on in this study: (a) conceptual discrete fracture fluid flow modeling incorporating a stochastic fracture network with numerical flow simulations; (b) estimation of REV and hydraulic conductivity tensor for fractured rocks utilizing a stochastic fracture network with numerical fluid flow simulations; (c) investigation of the effect of fracture orientation and density on the hydraulic conductivity and REV by implementing a stochastic fracture network with numerical fluid flow simulations, and (d) fluid flow conceptual models accounting for major and minor fractures in the 2 D or 3 D flow fields incorporating a stochastic fracture network with numerical fluid flow simulations.
文摘Context Theory have been extensively used in the teaching of minority English majors. Meanwhile, teachers of English in China have been inevitably involved in language testing of various types, either to choose an appropriate existing language test or design by themselves. Therefore it is of practical significance to testify whether the course taken under the Context Theory has enabled teachers to become competent in the design, development, and use of language tests. The main purpose of the present study is to analyze the quality of English grammar paper to check whether minority English majors' management of English grammar have been improved.