By using the ultraviolet absorption spectrum,the fluorescence spectrum and three dimensional fluorescence spectra,the composition of dissolved organic matter(DOM) and the humification degree,etc.in the sediment of hyd...By using the ultraviolet absorption spectrum,the fluorescence spectrum and three dimensional fluorescence spectra,the composition of dissolved organic matter(DOM) and the humification degree,etc.in the sediment of hydro-fluctuation belt(Yunyang part) were analyzed.The relationship between the test parameters and the pollution degree in the region was discussed.The research results of UV spectrum data E3/E4 showed that in 4 sampling sites which included Huangshi Town,Gaoyang Town,Shuangjiang Town and Quma Town,the humification degree in the sediment of hydro-fluctuation belt in Shuangjiang Town sampling site was lower,and the aromaticity was smaller.Moreover,the effect of human factor was comparatively smaller.The fluorescence index value which represented the source of humus in DOM was 1.62-1.88.It showed that the biological and terrestrial source both existed.Three dimensional spectra results showed that the pollution degrees in 4 sampling sites were all smaller,and some prevention measures should be taken early.展开更多
Xinjiang is known as the oasis irrigation agricultural area, characterized by plenty of sunshine favorable for cotton growth. However, the oases, dotted in the gobi deserts, are distributed at the foot of the enclosed...Xinjiang is known as the oasis irrigation agricultural area, characterized by plenty of sunshine favorable for cotton growth. However, the oases, dotted in the gobi deserts, are distributed at the foot of the enclosed mountains and a steppe in the centre of the Turpan Basin, and thus has a rathe vulnerable eco-environment. Since the 1980s, the cotton-growing industry has developed very quickly. The area of cotton-growing belt has increased from 181,000 hectares in 1980 to 866,600 hectares in 1997, which accounted for 34.7% of the total cultivated area in Xinjiang. The cotton output has correspondingly increased from 79,200 tons to 1.05 million tons and per hectare output has also increased from 438 kg to 1211 kg[1]. In recent decades, changes have taken place in agricultural products, such as the ratio of cotton and grain, total output and per hectare output with the expansion of cotton-growing belt. Before 1982, per hectare cotton output remained below 450 kg. Since 1982, thanks to the adoption of plastic film technique and such a planation mode as 'short, dense and early', namely, to select short-stalked, close planting and early maturing varieties, the per hectare cotton output has undergone a steady increase. After 1984, per hectare output reached more than 900 kg, and since 1995 it has reached 1435 kg per hectare, 9 folds more than that in the 1950s[1,2]. However the harmful organisms have accompanied the repaid expansion of the cotton-growing belt and the degree of deterioration has also kept increasing. Harmful organisms present a bottleneck for the further development of cotton production. To effectively control and protect against harmful organisms is the key to guaranteeing the steady development of Xinjiang cotton industry.展开更多
Distribution characteristics of soil organic matter(SOM) and total nitrogen(TN) were studied in different plant communities of the Yajiageng vertical belt in Gongga Mountain around the Dadu River banks. The result...Distribution characteristics of soil organic matter(SOM) and total nitrogen(TN) were studied in different plant communities of the Yajiageng vertical belt in Gongga Mountain around the Dadu River banks. The results show: (1) the contents of SOM and TN of the plant communities gradually decreased with the following order: subalpine coniferous forest (3 027 m), subalpine meadow (3 873 m), coniferous broadleaved mixed forest(2 737 m), subalpine shrub(3 565 m) and treeline(3 564 m). (2) With soil profile depth increasing, the contents of SOM and TN gradually decreased. For different vegetation types, the contents of SOM and TN in sub-alpine coniferous forest were higher than that of other vegetational types. (3)The ratio of the content of carbon to the content of total nitrogen (Cc/CTN)WaS 13.5-27.6, which was relatively lower than the appropriate Cc/CTN of 25-30, and indicated that the soil in favor of the organic matter decomposed and nutrients released. Cc/CTN in the soil had no correlation with sea level altitude. However, its distribution in the soil x, aried with different vegetation types. (4) Nitrogen in SOM existed mainly in the form of organic nitrogen, and Cc/CTN in the soil was not obvious correlated with SOM and TN.展开更多
Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied. The effects of shake speed, hydrophobicity of organic solvent,...Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied. The effects of shake speed, hydrophobicity of organic solvent, volume ratio of water phase to organic phase, pH value of aqueous phase and reaction temperature on the initial reaction rate, maximum yield and enantiomeric excess (ee) of the product were systematically explored. All the above-mentioned factors had significant influence on the reaction. n-Hexane was found to be the best organic solvent for the reaction. The optimum shake speed, volume ratio of water phase to organic phase, pH value and reaction temperature were 150 r.min-1, 1/2, 8 and 30 ℃ respectively, under which the maximum yield and enantiomeric excess of the product were as high as 96.8% and 95.7%, which are 15% and 16% higher than those of the corresponding reaction performed in aqueous phase. To our best knowledge, this is the most satisfactory result obtained.展开更多
The fabrication of S-scheme heterojunctions with fast charge transfer and good interface contacts,such as intermolecularπ–πinteractions,is a promising approach to improve photocatalytic performance.A unique two-dim...The fabrication of S-scheme heterojunctions with fast charge transfer and good interface contacts,such as intermolecularπ–πinteractions,is a promising approach to improve photocatalytic performance.A unique two-dimensional/two-dimensional(2D/2D)S-scheme heterojunction containing TpPa-1-COF/g-C_(3)N_(4) nanosheets(denoted as TPCNNS)was developed.The established maximum interfacial interaction between TpPa-1-COF NS and g-C_(3)N_(4) NS may result in aπ–πconjugated heterointerface.Furthermore,the difference in the work functions of TpPa-1-COF and g-C_(3)N_(4) results in a large Fermi level gap,leading to upward/downward band edge bending.The spontaneous interfacial charge transfer from g-C_(3)N_(4) to TpPa-1-COF at theπ–πconjugated interface area results in the presence of a built-in electric field,according to the charge density difference analysis based on density functional theory calculations.Such an enhanced built-in electric field can efficiently drive directional charge migration via the S-scheme mechanism,which enhances charge separation and utilization.Thus,an approximately 2.8 and 5.6 times increase in the photocatalytic hydrogen evolution rate was recorded in TPCNNS-2(1153μmol g^(-1) h^(-1))compared to pristine TpPa-1-COF and g-C_(3)N_(4) NS,respectively,under visible light irradiation.Overall,this work opens new avenues in the fabrication of 2D/2Dπ–πconjugated S-scheme heterojunction photocatalysts with highly efficient hydrogen evolution performance.展开更多
Deformation characteristics of the dextral Dashankou ductile shear zone , parallel to the Tongbo-Dabie Orogenic Belt and regional stretching lineation patterns within the blueschist belt in Northern Hubei , China , ar...Deformation characteristics of the dextral Dashankou ductile shear zone , parallel to the Tongbo-Dabie Orogenic Belt and regional stretching lineation patterns within the blueschist belt in Northern Hubei , China , are examined at various scales , respectively . The new data , combined with those obtained in the Wudangshan area , indicate a transpressive deformation involving a WNW directed nearly horizontal shearing accompanied by shortening across the orogenic belt . A kinematic model is proposed for development of the deformation within the Tongboshan segment . Based on these findings it can be seen that the convergence and collision between the North China Craton and the Yangtze Craton may locally be oblique during the Proterozoic Jinningian Orogeny . This oblique collision is probably related to a certain extent to the shapes of the older craton margins .展开更多
The Belt and Road Initiative is a new concept of opening-up put forward by Chinese leader Xi Jinping after he took office.It is the most influential international initiative since China’s reform and opening up.Its im...The Belt and Road Initiative is a new concept of opening-up put forward by Chinese leader Xi Jinping after he took office.It is the most influential international initiative since China’s reform and opening up.Its implementation has achieved remarkable results in the past few years,with more than expected results.More and more countries in the world have supported and responded to the Belt and Road Initiative.China and the UK are countries with important influence in the world.The Belt and Road Initiative has great potential and far-reaching impact between two countries.This paper analyzes the theory of influence of the Belt and Road and discusses the practical problems existing in the China-UK Belt and Road Cooperation.By applying the research method of matching theory with reality,the author puts forward some measures to enhance the influence of the Belt and Road Cooperation between the two countries.It is of great academic and practical significance to study the Belt and Road Theory and the international relations between China and Britain.展开更多
An organic material, namely, ethyl p-dimethylamino benzoate was crystallized for the first time by solution growth technique using pure and mixed solvents. Growth kinetics and morphology changes with solvents were inv...An organic material, namely, ethyl p-dimethylamino benzoate was crystallized for the first time by solution growth technique using pure and mixed solvents. Growth kinetics and morphology changes with solvents were investigated based on solute –solvent interactions of pure and mixed solvents. An appropriate mixed solvent for high quality crystals with well-defined morphology is reported. The absence of solvent molecules and the presence of various functional groups of the grown sample were qualitatively confirmed by FTIR spectroscopic studies. Thermal properties of the grown sample were analyzed by TG and DTA analysis. Mechanical properties of the EDMAB crystal were investigated by micro hardness studies. Moreover, the grown crystal shows high transparency in the visible and near IR regions. The material shows relatively high SHG efficiency than that of KDP.展开更多
The polymerization of methyl methacrylate (MMA) initiated by organic peroxide and polymerizable aromatic tertiary amine such as N, N-di (2-α-methylacryloyloxy propyl)-p-toluidine (MP)_2PT binary system has been studi...The polymerization of methyl methacrylate (MMA) initiated by organic peroxide and polymerizable aromatic tertiary amine such as N, N-di (2-α-methylacryloyloxy propyl)-p-toluidine (MP)_2PT binary system has been studied. It was found that the (MP)_2PT promotes MMA polymerization, and the kinetics of MMA polymerization fits the radical polymerization rate equation. Based on the ESR studies and the end-group analysis the initiation mechanism is proposed.展开更多
White organic light-emitting diodes (WOLEDs) with a structure of indium-tin-oxide (ITO)/N,N'-bis- (1-naphthyl)-N,N'-diphenyl- (1, 1'-biphenyl)-4,4'-diamine (NPB)/1,2,3,4,5,6-hexakis(9,9-diethyl-9H-fluor...White organic light-emitting diodes (WOLEDs) with a structure of indium-tin-oxide (ITO)/N,N'-bis- (1-naphthyl)-N,N'-diphenyl- (1, 1'-biphenyl)-4,4'-diamine (NPB)/1,2,3,4,5,6-hexakis(9,9-diethyl-9H-fluoren-2- yl)benzene (HKEthFLYPh)/5,6,11,12-tetraphenylnaphtacene (rubrene)/tris(8-hydroxyquinoline) aluminum (Alq3)/Mg:Ag were fabricated by vacuum deposition method, in which a novel star-shaped hexafluorenyl- benzene HKEthFLYPh was used as an energy transfer layer, and an ultrathin layer of rubrene was inserted between HKEthFLYPh and Alq3 layers as a yellow light-emitting layer instead of using a time-consuming doping process. A fairly pure WOLED with Commissions Internationale De L'Eclairage (CIE) coordinates of (0.32, 0.33) was obtained when the thickness of rubrene was 0.3 nm, and the spectrum was insensitive to the applied voltage. The device yielded a maximum luminance of 4816 cd/m2 at 18 V.展开更多
This paper presents the results of the search of biologically active uranium compounds such as amino acids. We first received and examined X-ray and IR (infrared radiation) spectroscopy of uranium complexes with α-...This paper presents the results of the search of biologically active uranium compounds such as amino acids. We first received and examined X-ray and IR (infrared radiation) spectroscopy of uranium complexes with α- and β-amino acids in aqueous and organic solution. We proposed a method for direct synthesis of complex organic compounds of uranium chloride UO2Cl2 with α- andβ-amino acids for the synthesis of drugs for the treatment of cancer.展开更多
As a flagship project of Sino-Indonesia cooperation within the framework of“the Belt and Road”Initiative(BRI),Jakarta-Bandung High Speed Railway(Jakarta-Bandung HSR)is the first overseas high speed railway entirely ...As a flagship project of Sino-Indonesia cooperation within the framework of“the Belt and Road”Initiative(BRI),Jakarta-Bandung High Speed Railway(Jakarta-Bandung HSR)is the first overseas high speed railway entirely implementing China's high speed railway technology with all systems,elements and industrial chain.It marks the success of extensive consultation,joint contribution and shared benefits between China and region states to achieve modernization.By studying the Jakarta-Bandung HSR project,this paper concludes the innovations and successful practices in“going global”of China's railway industry in terms of project organization,engineering construction,railway equipment,operation management,risk prevention and control,etc.Meanwhile,focusing on one of the eight major steps to support high-quality Belt and Road cooperation proposed by President Xi Jinping—building a multidimensional“the Belt and Road”connectivity network,this paper puts forward the specific outlook for China's high speed railway to“go global”and jointly build“the Belt and Road”Initiative from two perspectives of international railway engineering and international scientific and technological cooperation.展开更多
基金Supported by Talent Introduction Talent Plan of Chongqing ThreeGorge University(2007-SXXYRC-006)Accented Term of ChongqingThree Gorge University(10ZD-14)+1 种基金Special Term of National Water Body Pollution Control and Treatment Major Project(2009ZX07104-003-02)Special Term of National Science and Technology Supportm Plan Major Project(2008BAD98B04)
文摘By using the ultraviolet absorption spectrum,the fluorescence spectrum and three dimensional fluorescence spectra,the composition of dissolved organic matter(DOM) and the humification degree,etc.in the sediment of hydro-fluctuation belt(Yunyang part) were analyzed.The relationship between the test parameters and the pollution degree in the region was discussed.The research results of UV spectrum data E3/E4 showed that in 4 sampling sites which included Huangshi Town,Gaoyang Town,Shuangjiang Town and Quma Town,the humification degree in the sediment of hydro-fluctuation belt in Shuangjiang Town sampling site was lower,and the aromaticity was smaller.Moreover,the effect of human factor was comparatively smaller.The fluorescence index value which represented the source of humus in DOM was 1.62-1.88.It showed that the biological and terrestrial source both existed.Three dimensional spectra results showed that the pollution degrees in 4 sampling sites were all smaller,and some prevention measures should be taken early.
基金Supported by Light of Western Regions Project and Key Project of CAS Integrated Demonstration Project for Sustainable Developmen
文摘Xinjiang is known as the oasis irrigation agricultural area, characterized by plenty of sunshine favorable for cotton growth. However, the oases, dotted in the gobi deserts, are distributed at the foot of the enclosed mountains and a steppe in the centre of the Turpan Basin, and thus has a rathe vulnerable eco-environment. Since the 1980s, the cotton-growing industry has developed very quickly. The area of cotton-growing belt has increased from 181,000 hectares in 1980 to 866,600 hectares in 1997, which accounted for 34.7% of the total cultivated area in Xinjiang. The cotton output has correspondingly increased from 79,200 tons to 1.05 million tons and per hectare output has also increased from 438 kg to 1211 kg[1]. In recent decades, changes have taken place in agricultural products, such as the ratio of cotton and grain, total output and per hectare output with the expansion of cotton-growing belt. Before 1982, per hectare cotton output remained below 450 kg. Since 1982, thanks to the adoption of plastic film technique and such a planation mode as 'short, dense and early', namely, to select short-stalked, close planting and early maturing varieties, the per hectare cotton output has undergone a steady increase. After 1984, per hectare output reached more than 900 kg, and since 1995 it has reached 1435 kg per hectare, 9 folds more than that in the 1950s[1,2]. However the harmful organisms have accompanied the repaid expansion of the cotton-growing belt and the degree of deterioration has also kept increasing. Harmful organisms present a bottleneck for the further development of cotton production. To effectively control and protect against harmful organisms is the key to guaranteeing the steady development of Xinjiang cotton industry.
基金the National Basic Research Program of China (973 Program) (2005CB422005)
文摘Distribution characteristics of soil organic matter(SOM) and total nitrogen(TN) were studied in different plant communities of the Yajiageng vertical belt in Gongga Mountain around the Dadu River banks. The results show: (1) the contents of SOM and TN of the plant communities gradually decreased with the following order: subalpine coniferous forest (3 027 m), subalpine meadow (3 873 m), coniferous broadleaved mixed forest(2 737 m), subalpine shrub(3 565 m) and treeline(3 564 m). (2) With soil profile depth increasing, the contents of SOM and TN gradually decreased. For different vegetation types, the contents of SOM and TN in sub-alpine coniferous forest were higher than that of other vegetational types. (3)The ratio of the content of carbon to the content of total nitrogen (Cc/CTN)WaS 13.5-27.6, which was relatively lower than the appropriate Cc/CTN of 25-30, and indicated that the soil in favor of the organic matter decomposed and nutrients released. Cc/CTN in the soil had no correlation with sea level altitude. However, its distribution in the soil x, aried with different vegetation types. (4) Nitrogen in SOM existed mainly in the form of organic nitrogen, and Cc/CTN in the soil was not obvious correlated with SOM and TN.
基金Supported by the National Natural Science Foundation of China(No.20076019)the Natural Science Foundation of Guang-dong Province(No.000444).
文摘Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied. The effects of shake speed, hydrophobicity of organic solvent, volume ratio of water phase to organic phase, pH value of aqueous phase and reaction temperature on the initial reaction rate, maximum yield and enantiomeric excess (ee) of the product were systematically explored. All the above-mentioned factors had significant influence on the reaction. n-Hexane was found to be the best organic solvent for the reaction. The optimum shake speed, volume ratio of water phase to organic phase, pH value and reaction temperature were 150 r.min-1, 1/2, 8 and 30 ℃ respectively, under which the maximum yield and enantiomeric excess of the product were as high as 96.8% and 95.7%, which are 15% and 16% higher than those of the corresponding reaction performed in aqueous phase. To our best knowledge, this is the most satisfactory result obtained.
文摘The fabrication of S-scheme heterojunctions with fast charge transfer and good interface contacts,such as intermolecularπ–πinteractions,is a promising approach to improve photocatalytic performance.A unique two-dimensional/two-dimensional(2D/2D)S-scheme heterojunction containing TpPa-1-COF/g-C_(3)N_(4) nanosheets(denoted as TPCNNS)was developed.The established maximum interfacial interaction between TpPa-1-COF NS and g-C_(3)N_(4) NS may result in aπ–πconjugated heterointerface.Furthermore,the difference in the work functions of TpPa-1-COF and g-C_(3)N_(4) results in a large Fermi level gap,leading to upward/downward band edge bending.The spontaneous interfacial charge transfer from g-C_(3)N_(4) to TpPa-1-COF at theπ–πconjugated interface area results in the presence of a built-in electric field,according to the charge density difference analysis based on density functional theory calculations.Such an enhanced built-in electric field can efficiently drive directional charge migration via the S-scheme mechanism,which enhances charge separation and utilization.Thus,an approximately 2.8 and 5.6 times increase in the photocatalytic hydrogen evolution rate was recorded in TPCNNS-2(1153μmol g^(-1) h^(-1))compared to pristine TpPa-1-COF and g-C_(3)N_(4) NS,respectively,under visible light irradiation.Overall,this work opens new avenues in the fabrication of 2D/2Dπ–πconjugated S-scheme heterojunction photocatalysts with highly efficient hydrogen evolution performance.
文摘Deformation characteristics of the dextral Dashankou ductile shear zone , parallel to the Tongbo-Dabie Orogenic Belt and regional stretching lineation patterns within the blueschist belt in Northern Hubei , China , are examined at various scales , respectively . The new data , combined with those obtained in the Wudangshan area , indicate a transpressive deformation involving a WNW directed nearly horizontal shearing accompanied by shortening across the orogenic belt . A kinematic model is proposed for development of the deformation within the Tongboshan segment . Based on these findings it can be seen that the convergence and collision between the North China Craton and the Yangtze Craton may locally be oblique during the Proterozoic Jinningian Orogeny . This oblique collision is probably related to a certain extent to the shapes of the older craton margins .
文摘The Belt and Road Initiative is a new concept of opening-up put forward by Chinese leader Xi Jinping after he took office.It is the most influential international initiative since China’s reform and opening up.Its implementation has achieved remarkable results in the past few years,with more than expected results.More and more countries in the world have supported and responded to the Belt and Road Initiative.China and the UK are countries with important influence in the world.The Belt and Road Initiative has great potential and far-reaching impact between two countries.This paper analyzes the theory of influence of the Belt and Road and discusses the practical problems existing in the China-UK Belt and Road Cooperation.By applying the research method of matching theory with reality,the author puts forward some measures to enhance the influence of the Belt and Road Cooperation between the two countries.It is of great academic and practical significance to study the Belt and Road Theory and the international relations between China and Britain.
文摘An organic material, namely, ethyl p-dimethylamino benzoate was crystallized for the first time by solution growth technique using pure and mixed solvents. Growth kinetics and morphology changes with solvents were investigated based on solute –solvent interactions of pure and mixed solvents. An appropriate mixed solvent for high quality crystals with well-defined morphology is reported. The absence of solvent molecules and the presence of various functional groups of the grown sample were qualitatively confirmed by FTIR spectroscopic studies. Thermal properties of the grown sample were analyzed by TG and DTA analysis. Mechanical properties of the EDMAB crystal were investigated by micro hardness studies. Moreover, the grown crystal shows high transparency in the visible and near IR regions. The material shows relatively high SHG efficiency than that of KDP.
文摘The polymerization of methyl methacrylate (MMA) initiated by organic peroxide and polymerizable aromatic tertiary amine such as N, N-di (2-α-methylacryloyloxy propyl)-p-toluidine (MP)_2PT binary system has been studied. It was found that the (MP)_2PT promotes MMA polymerization, and the kinetics of MMA polymerization fits the radical polymerization rate equation. Based on the ESR studies and the end-group analysis the initiation mechanism is proposed.
基金This work was supported by the National Natural Science Foundation of China (No.60425101 and No.20674049), the Program for New Century Excellent Talents in University (No.NCET-06-0812), and the Young Talent Project at University of Electronic Science and Technology of China (No.060206).
文摘White organic light-emitting diodes (WOLEDs) with a structure of indium-tin-oxide (ITO)/N,N'-bis- (1-naphthyl)-N,N'-diphenyl- (1, 1'-biphenyl)-4,4'-diamine (NPB)/1,2,3,4,5,6-hexakis(9,9-diethyl-9H-fluoren-2- yl)benzene (HKEthFLYPh)/5,6,11,12-tetraphenylnaphtacene (rubrene)/tris(8-hydroxyquinoline) aluminum (Alq3)/Mg:Ag were fabricated by vacuum deposition method, in which a novel star-shaped hexafluorenyl- benzene HKEthFLYPh was used as an energy transfer layer, and an ultrathin layer of rubrene was inserted between HKEthFLYPh and Alq3 layers as a yellow light-emitting layer instead of using a time-consuming doping process. A fairly pure WOLED with Commissions Internationale De L'Eclairage (CIE) coordinates of (0.32, 0.33) was obtained when the thickness of rubrene was 0.3 nm, and the spectrum was insensitive to the applied voltage. The device yielded a maximum luminance of 4816 cd/m2 at 18 V.
文摘This paper presents the results of the search of biologically active uranium compounds such as amino acids. We first received and examined X-ray and IR (infrared radiation) spectroscopy of uranium complexes with α- and β-amino acids in aqueous and organic solution. We proposed a method for direct synthesis of complex organic compounds of uranium chloride UO2Cl2 with α- andβ-amino acids for the synthesis of drugs for the treatment of cancer.
文摘As a flagship project of Sino-Indonesia cooperation within the framework of“the Belt and Road”Initiative(BRI),Jakarta-Bandung High Speed Railway(Jakarta-Bandung HSR)is the first overseas high speed railway entirely implementing China's high speed railway technology with all systems,elements and industrial chain.It marks the success of extensive consultation,joint contribution and shared benefits between China and region states to achieve modernization.By studying the Jakarta-Bandung HSR project,this paper concludes the innovations and successful practices in“going global”of China's railway industry in terms of project organization,engineering construction,railway equipment,operation management,risk prevention and control,etc.Meanwhile,focusing on one of the eight major steps to support high-quality Belt and Road cooperation proposed by President Xi Jinping—building a multidimensional“the Belt and Road”connectivity network,this paper puts forward the specific outlook for China's high speed railway to“go global”and jointly build“the Belt and Road”Initiative from two perspectives of international railway engineering and international scientific and technological cooperation.