Soil environment in Sanjiang Plain has changed greatly because of the reclamation on a large scale.The physical and chemical properties of soil have changed, and soil erosion, soil saline-alkalization and soil polluti...Soil environment in Sanjiang Plain has changed greatly because of the reclamation on a large scale.The physical and chemical properties of soil have changed, and soil erosion, soil saline-alkalization and soil pollution occurred in some areas. These problems have obstructed the sustainable development of agriculture. For the sustainable use of soils in Sanjiang Plain, in this paper we raise some suggestions and countermeasures which might be references for experts and departments concerned.展开更多
Aim: To investigate the transforming growth factor β_1 (TGF-β_1) and basic fibroblast growth factor (bFGF) expressions in benign prostatic hyperplasia (BPH) and the effect of β-radiation. Methods: TGF-β_1 and bFGF...Aim: To investigate the transforming growth factor β_1 (TGF-β_1) and basic fibroblast growth factor (bFGF) expressions in benign prostatic hyperplasia (BPH) and the effect of β-radiation. Methods: TGF-β_1 and bFGF expression was studied by means of an immunohistochemical method in nine normal prostatic (NP) tissues, 15 hyperplastic prostatic tissues and 35 hyperplastic prostatic tissues treated with ^(90)Sr/^(90)Y. Results: The TGF-β_1 expression in the epithelium and stroma of normal prostatic tissues was 68.2 % ± 10.5 % and 29.7 % ± 4.6 %, respectively, while it was 64.8 % ± 9.3 % and 28.6 % ± 4.1%, respectively, in hyperplastic prostatic tissues. Compared with the controls, TGF-β_1 expression in the epithelia and stroma of BPH treated with ^(90)Sr/^(90)Y increased significantly (P < 0.01). The bFGF expression in epithelia and stroma of normal prostatic tissues was 17.4 % ± 3.7 % and 42.5 % ± 6.8 %, respectively, and was 46.3 % ± 8.2 % and 73.2 % ± 12.1%, respectivley, in hyperplastic prostatic tissues. Compared with the controls, expressions of bFGFin the epithelia and stroma of BPH treated with a ^(90)Sr/^(90)Y prostatic hyperplasia applicator decreased significantly (P < 0.01). Conclusion: Exposure of β-rays had noticeable effects on BPH tissues, enhancing TGF-β_1 expression and inhibiting bFGF expression.展开更多
This paper reviewed the development of Strategic Environmental Assessment (SEA) in China, expounded its functions and regional characteristics, and discussed the targets of SEA in the process of urbanization,and the m...This paper reviewed the development of Strategic Environmental Assessment (SEA) in China, expounded its functions and regional characteristics, and discussed the targets of SEA in the process of urbanization,and the main assessment indicators, procedures, techniques and methodologies of SEA. It concluded that SEA could be improved by the following recommendations: incorporating SEA in decision-making process, selecting experimental units for SEA trial run, and developing strategic evaluation tools and techniques. SEA can provide appropriate and up-to-date information on the impact of human activity on environment in the process of urbanization, and develop a plan of action targeting implementation of intervention for the rehabilitation and preservation of the ecological stability of a city. Therefore, SEA can be a supporting tool for decision-making toward achieving sustainable development.展开更多
This paper deals with reflection spectra and polarized reflection spectra of 20 sorts of rock in 2π space, and then creates a model of reflection spectra of rock surface in 2π space. We measured the change of reflec...This paper deals with reflection spectra and polarized reflection spectra of 20 sorts of rock in 2π space, and then creates a model of reflection spectra of rock surface in 2π space. We measured the change of reflection and polarized reflection spectra as altering the incidence angle, vertex angle, azimuth angle, band and polarization. The results show that influence of the incidence angle on spectral curves is very strong. And when the vertex angle is constant, the horizontal azimuth polarizes rock spectra, and distorts the circular spectrum to become elliptic. The polarization influences the reflection intensity of rock spectra, but has no evident influence on the characteristics of wave forms of rock in 2π space. Therefore, we can describe the whole reflection spectral characteristics, including polarization, of rock surface in 2π space by measuring and calculating the e and p values in several key directions.展开更多
Thin PVA/nickel acetate composite fibres were prepared by using sol-gel processing and electrospinning technique. After calcination of the above precursor fibres, NiO nanofibres with a diameter of 50-150 nm could be ...Thin PVA/nickel acetate composite fibres were prepared by using sol-gel processing and electrospinning technique. After calcination of the above precursor fibres, NiO nanofibres with a diameter of 50-150 nm could be successfully obtained. The fibres were characterized by SEM, FT-IR, WAXD, respectively.展开更多
Data collection, factor composition, nappe analysis and integrative simulation of natural geographical factors in Erlong Lake watershed have been carried out based on GIS. The risk areas where non-point source polluti...Data collection, factor composition, nappe analysis and integrative simulation of natural geographical factors in Erlong Lake watershed have been carried out based on GIS. The risk areas where non-point source pollution may occur were compartmentalized and assessed, and the total soil erosion and the runoffs of N and P with rainfall in this valley were worked out by experiment and GIS mapping. The study indicated that the main type of soil erosion was moderate (erosion modulus is 1000-2500t/(km(2).a)) at present, and the intense erosion areas are located in dry land with variable slope east of the lake and the middle-south parts of steep slope mountainous region (erosion modulus is more than 5000t/(km(2).a)). Though the area is small, it should be paid attention to. The trend of non-point source pollution (NSP) of nitrogen and phosphorus loss was corresponded with the soil erosion. Spatial distribution and the reasons of the distribution difference have been presented and it was emphasized that the human activities among the influence factors was the most important. It surely offers a scientific basis to control and prevent non-point source pollution in the watershed.展开更多
The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-m...The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-ment assessment (SEA)on land-use planning.The whole article includes three main parts:firstly,some attribute database,graphic-base and the spatial transform matrix,which reflect the change of regional land-use pattern,can be ob-tained by GIS technique;secondly,a dopting fitting method of trend-sur face analysis will convert environm ent monitoring data from scattered spots to regular control spots,based on which we can p erform regional environment impact assess-ment;finally,Changchun Economic a nd Technological Developmen Zone is chosen as a case study on land-use pla nning.Through those efforts the results ma y be obtained as follows:1)according to transform matrix,the p ossibility of transforma-tion from one land-use to another can be obtained after the planning is carried out;2)environment quality would change as a result of the change of land-use p attern;3)the SEA on land-use plan is an effecti ve tool to make land-use pattern more reasonable.展开更多
This paper described new development of the neutron induced prompt gamma-ray analysis(NIPGA) technology in 1988-2003.The pulse fast-thermal neutron activation analysis method,which utilized the inelastic reaction and ...This paper described new development of the neutron induced prompt gamma-ray analysis(NIPGA) technology in 1988-2003.The pulse fast-thermal neutron activation analysis method,which utilized the inelastic reaction and capture reaction jointly,was employed to measure the elemental contents more efficiently.Lifetime of the neutron generator was more than 10000h and the performance of detector and MCA reached a high level.At the same time,Monte Carlo library least-square method was used to solve the nonlinearity problem in the NIPGA.展开更多
A water-soluble pectin SB_~1-1 was isolated and purified from the root of Panax ginseng C. A. Mey. The HPLC analysis indicates that SB_~1-1 is homogenous. Its molecular weight was estimated via gel filtration to be 10...A water-soluble pectin SB_~1-1 was isolated and purified from the root of Panax ginseng C. A. Mey. The HPLC analysis indicates that SB_~1-1 is homogenous. Its molecular weight was estimated via gel filtration to be 10000. The GC analysis indicated that it contains the monosaccharides of GalA, Gal, Ara and Rha. Their molar ratio is 2.10∶1.00∶0.12∶0.13. Partial hydrolysis with acid, pectinase treatment, periodate oxidation, Smith degradation, methylation analyses, GC/MS analyses and NMR analyses were used for the structure analyses of SB_~1-1 . The results reveal that SB_~1-1 has a lower branched structure. The main chain is composed of GalA and Gal; the inner part is α-1,4-linked-GalA; the border is 1,4-linked-Gal. Some of the 1,4-linked-GalA and 1,4-linked-Gal residues are substituted at O6. On an average, there is one branch for every ten hexose residues. The side chain is composed of 1,6-linked-Gal and 1,3,6-linked-Gal. The nonreduced end is composed of Rha, Ara and Gal. The main glycosidic link of SB_~1-1 has an α configuration.展开更多
A novel compound, (HGly) 4[HPMo 12 O 40 ] 2·22H 2O, was synthesized and characterized by means of elemental analysis, IR and X ray diffraction. The compound crystallized in a monoclinic space group ...A novel compound, (HGly) 4[HPMo 12 O 40 ] 2·22H 2O, was synthesized and characterized by means of elemental analysis, IR and X ray diffraction. The compound crystallized in a monoclinic space group Cc with a =4 0060(0 8) nm, b =1 2527(0 3) nm, c =1 9930(0 4) nm, β =96 36(3)°, V =9 940(3) nm 3, Z =2, R 1=0 0576, wR 2 =0 1746. The anti tumor activity of this compound was tested in two human tumor cell lines in vitro .展开更多
This paper introduces a new concept of community-based ecotourism (CBET) that originated in foreign countries. Then it analyzes the significance of CBET development in nature reserve (NR). The authors think that commu...This paper introduces a new concept of community-based ecotourism (CBET) that originated in foreign countries. Then it analyzes the significance of CBET development in nature reserve (NR). The authors think that community participation is the evitable choice of nature reserve′s conservation and development. CBET, as the self-improved model of ecotourism, can promote tourism community sustainable development. Based on the stakeholder analysis of CBET in NRs, this paper addresses the reality, especially the problem of CBET development in NRs of China. In order to develop CBET in NRs of China, this paper takes some suggestions to promote the community participation: 1)gradual political empowerment, 2) deep level economic incentive, 3) widespread educational support, 4) impartial distribution of community benefits, and 5) stakeholders cooperation.展开更多
The ecological series of soil animals under the broad-leaved and pine mix ed forest in Darlidai Mountain was studied.Seven sample plots were selected according to different altitude gradients,which belong to dif feren...The ecological series of soil animals under the broad-leaved and pine mix ed forest in Darlidai Mountain was studied.Seven sample plots were selected according to different altitude gradients,which belong to dif ferent vegeta-tion types.By investigating and analyzing soil animals in every sample p lot it is found that there are 45group s and 1956individuals,which are involved in 3phylums,7classes,16orders,respectively.The altitude is a key factor which af-fects ecological series of soil anim als.Both the groups and individuals of soil animals increase with altitu de increasing under certain conditions,which con trastes with ordinary cases,resulting from special micro-climate in studied area.The groups and individuls of soil animals are the most under the broad-leaved and pine forest on the top of the mount ain,and the least under Picea-Abies forest in the foot of the mountain.展开更多
A new compound, (C 6H 6N 3) 7(PMo Ⅵ 12 O 40 )(PMo ⅤMo Ⅵ 11 O 40 )·2CH 3CH 2OH·5H 2O, was synthesized and characterized by means of elemental analyses, IR spectroscopy, 1H N...A new compound, (C 6H 6N 3) 7(PMo Ⅵ 12 O 40 )(PMo ⅤMo Ⅵ 11 O 40 )·2CH 3CH 2OH·5H 2O, was synthesized and characterized by means of elemental analyses, IR spectroscopy, 1H NMR spectroscopy and single crystal \{X ray\} diffraction. This is the first example of benzotriazole polyoxometalates species. The compound crystallized in a triclinic space group P 1 with a =1 8378(4) nm, b =1 9078(4) nm, c =2 1037 (4) nm, α =\{63 41(3)°\}, β =64 31(3)°, γ =68 38(3)°, V =5 803(2) nm 3, Z =2, R 1=0 0486, wR 2=0 1357. The X ray crystallographic study showed that the crystal structure was constructed by electrostatic interactions and hydrogen bonds between dodecamolybdophosphorate anions and protonated benzotriazole cations. The electrochemical behavior and the reduction of nitrite and hydrogen peroxide electrocatalyzed by the title compound were studied.展开更多
The main purpose of this study is to give evaluation of ecological services of Jilin Province, Northeast China. To take this value into decision-making and GDP accounting system is considered to be one of the economic...The main purpose of this study is to give evaluation of ecological services of Jilin Province, Northeast China. To take this value into decision-making and GDP accounting system is considered to be one of the economic solutions for ecological problems. The evaluation is based on the methods proposed by COSTANZA et al., and some modifications about unit value of forest and cropland system were made according to the real characters of ecosystem, climate, natural conditions etc., in Jilin Province. Total value of ecosystem services is about 554.404x10(9) yuan(RMB)/a, which is about 4.9 times of GDP of the corresponding period. The results of this study could be used as a fundamental work for the construction of ecological province, which was carried out from 2001, and could provide ecological information for decision-making. Furthermore, the necessities for the further studies on the evaluation of ecological services and natural capital were discussed.展开更多
The sandy land of the western part of Jilin Province is located in the ecotone of semi-humid and semi-arid area in the temperate zone of China. The sandy desertification has widely spread in the...The sandy land of the western part of Jilin Province is located in the ecotone of semi-humid and semi-arid area in the temperate zone of China. The sandy desertification has widely spread in the region because of the vulnerable natural conditions and the unreasonable human activity; as a result of this, the precious land resources and the economic development in the area have been seriously impacted. In this paper, the sandy land ecologic environment geographic information system is established based on the multi-spectral, multi-temporal Landsat TM images and field investigation. The comprehensive indexes of sandy desertification extent assessment which include vegetation degradation, wind erosion extent and soil depth are presented to classify the sandy land in western Jilin into three levels--slight, moderate and severe sandy desertification with the support of GIS platform. The results demonstrate that the sandy desertification has been partly controlled in the past twenty years, except some small sites. However, this doesn't necessarily mean that there is nothing for more concern. The two main causes of sandy desertification have not been eliminated yet, one is its natural factor, especially the physical and chemical characters of sandy soil and dry climate; another is the immoderate economic activity of human being that has highly accelerated the sandy desertification process.展开更多
The essential oil of Schisandra Chinensis(Turc z.) Baill was extracted and analyzed. The essential oil was obtained in a 1.8%(mL/100 g material) yield. Forty eight compounds were isolated and characterized from the oi...The essential oil of Schisandra Chinensis(Turc z.) Baill was extracted and analyzed. The essential oil was obtained in a 1.8%(mL/100 g material) yield. Forty eight compounds were isolated and characterized from the oil. The results show that the content(20.42%) of β -pinene of naturally essential oil is the highest among the components of the oil,which has laid a foundation for the futher development and application of the stems of Schisandra Chinensis(Turc z.) Baill .展开更多
dinitrotoluene(2,4 DNT), 2,6 dinitrotoluene(2,6 DNT) and 4 nitrotoluene(4 NT) are typical pollutants in the Songhua River of Northeast China. Sertoli/germ cell cocultures and single cell gel electrophoresis(SCGE) are ...dinitrotoluene(2,4 DNT), 2,6 dinitrotoluene(2,6 DNT) and 4 nitrotoluene(4 NT) are typical pollutants in the Songhua River of Northeast China. Sertoli/germ cell cocultures and single cell gel electrophoresis(SCGE) are applied to investigate whether they have genotoxicity on DNA damage of germ cell of Kunming male rat. The results showed that all three nitrotoluene compounds tested could induce DNA single strand breaks of the germ cell. A significant relationship is found between logarithm dose and the degree of DNA damage, which implies that 2,4 DNT, 2,6 DNT and 4 NT have genotoxicity and can induce the germ cell DNA strand to break in vitro.展开更多
文摘Soil environment in Sanjiang Plain has changed greatly because of the reclamation on a large scale.The physical and chemical properties of soil have changed, and soil erosion, soil saline-alkalization and soil pollution occurred in some areas. These problems have obstructed the sustainable development of agriculture. For the sustainable use of soils in Sanjiang Plain, in this paper we raise some suggestions and countermeasures which might be references for experts and departments concerned.
文摘Aim: To investigate the transforming growth factor β_1 (TGF-β_1) and basic fibroblast growth factor (bFGF) expressions in benign prostatic hyperplasia (BPH) and the effect of β-radiation. Methods: TGF-β_1 and bFGF expression was studied by means of an immunohistochemical method in nine normal prostatic (NP) tissues, 15 hyperplastic prostatic tissues and 35 hyperplastic prostatic tissues treated with ^(90)Sr/^(90)Y. Results: The TGF-β_1 expression in the epithelium and stroma of normal prostatic tissues was 68.2 % ± 10.5 % and 29.7 % ± 4.6 %, respectively, while it was 64.8 % ± 9.3 % and 28.6 % ± 4.1%, respectively, in hyperplastic prostatic tissues. Compared with the controls, TGF-β_1 expression in the epithelia and stroma of BPH treated with ^(90)Sr/^(90)Y increased significantly (P < 0.01). The bFGF expression in epithelia and stroma of normal prostatic tissues was 17.4 % ± 3.7 % and 42.5 % ± 6.8 %, respectively, and was 46.3 % ± 8.2 % and 73.2 % ± 12.1%, respectivley, in hyperplastic prostatic tissues. Compared with the controls, expressions of bFGFin the epithelia and stroma of BPH treated with a ^(90)Sr/^(90)Y prostatic hyperplasia applicator decreased significantly (P < 0.01). Conclusion: Exposure of β-rays had noticeable effects on BPH tissues, enhancing TGF-β_1 expression and inhibiting bFGF expression.
文摘This paper reviewed the development of Strategic Environmental Assessment (SEA) in China, expounded its functions and regional characteristics, and discussed the targets of SEA in the process of urbanization,and the main assessment indicators, procedures, techniques and methodologies of SEA. It concluded that SEA could be improved by the following recommendations: incorporating SEA in decision-making process, selecting experimental units for SEA trial run, and developing strategic evaluation tools and techniques. SEA can provide appropriate and up-to-date information on the impact of human activity on environment in the process of urbanization, and develop a plan of action targeting implementation of intervention for the rehabilitation and preservation of the ecological stability of a city. Therefore, SEA can be a supporting tool for decision-making toward achieving sustainable development.
文摘This paper deals with reflection spectra and polarized reflection spectra of 20 sorts of rock in 2π space, and then creates a model of reflection spectra of rock surface in 2π space. We measured the change of reflection and polarized reflection spectra as altering the incidence angle, vertex angle, azimuth angle, band and polarization. The results show that influence of the incidence angle on spectral curves is very strong. And when the vertex angle is constant, the horizontal azimuth polarizes rock spectra, and distorts the circular spectrum to become elliptic. The polarization influences the reflection intensity of rock spectra, but has no evident influence on the characteristics of wave forms of rock in 2π space. Therefore, we can describe the whole reflection spectral characteristics, including polarization, of rock surface in 2π space by measuring and calculating the e and p values in several key directions.
文摘Thin PVA/nickel acetate composite fibres were prepared by using sol-gel processing and electrospinning technique. After calcination of the above precursor fibres, NiO nanofibres with a diameter of 50-150 nm could be successfully obtained. The fibres were characterized by SEM, FT-IR, WAXD, respectively.
文摘Data collection, factor composition, nappe analysis and integrative simulation of natural geographical factors in Erlong Lake watershed have been carried out based on GIS. The risk areas where non-point source pollution may occur were compartmentalized and assessed, and the total soil erosion and the runoffs of N and P with rainfall in this valley were worked out by experiment and GIS mapping. The study indicated that the main type of soil erosion was moderate (erosion modulus is 1000-2500t/(km(2).a)) at present, and the intense erosion areas are located in dry land with variable slope east of the lake and the middle-south parts of steep slope mountainous region (erosion modulus is more than 5000t/(km(2).a)). Though the area is small, it should be paid attention to. The trend of non-point source pollution (NSP) of nitrogen and phosphorus loss was corresponded with the soil erosion. Spatial distribution and the reasons of the distribution difference have been presented and it was emphasized that the human activities among the influence factors was the most important. It surely offers a scientific basis to control and prevent non-point source pollution in the watershed.
文摘The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-ment assessment (SEA)on land-use planning.The whole article includes three main parts:firstly,some attribute database,graphic-base and the spatial transform matrix,which reflect the change of regional land-use pattern,can be ob-tained by GIS technique;secondly,a dopting fitting method of trend-sur face analysis will convert environm ent monitoring data from scattered spots to regular control spots,based on which we can p erform regional environment impact assess-ment;finally,Changchun Economic a nd Technological Developmen Zone is chosen as a case study on land-use pla nning.Through those efforts the results ma y be obtained as follows:1)according to transform matrix,the p ossibility of transforma-tion from one land-use to another can be obtained after the planning is carried out;2)environment quality would change as a result of the change of land-use p attern;3)the SEA on land-use plan is an effecti ve tool to make land-use pattern more reasonable.
基金Supported by Science Foundation for Young Teachers Normal University
文摘This paper described new development of the neutron induced prompt gamma-ray analysis(NIPGA) technology in 1988-2003.The pulse fast-thermal neutron activation analysis method,which utilized the inelastic reaction and capture reaction jointly,was employed to measure the elemental contents more efficiently.Lifetime of the neutron generator was more than 10000h and the performance of detector and MCA reached a high level.At the same time,Monte Carlo library least-square method was used to solve the nonlinearity problem in the NIPGA.
文摘A water-soluble pectin SB_~1-1 was isolated and purified from the root of Panax ginseng C. A. Mey. The HPLC analysis indicates that SB_~1-1 is homogenous. Its molecular weight was estimated via gel filtration to be 10000. The GC analysis indicated that it contains the monosaccharides of GalA, Gal, Ara and Rha. Their molar ratio is 2.10∶1.00∶0.12∶0.13. Partial hydrolysis with acid, pectinase treatment, periodate oxidation, Smith degradation, methylation analyses, GC/MS analyses and NMR analyses were used for the structure analyses of SB_~1-1 . The results reveal that SB_~1-1 has a lower branched structure. The main chain is composed of GalA and Gal; the inner part is α-1,4-linked-GalA; the border is 1,4-linked-Gal. Some of the 1,4-linked-GalA and 1,4-linked-Gal residues are substituted at O6. On an average, there is one branch for every ten hexose residues. The side chain is composed of 1,6-linked-Gal and 1,3,6-linked-Gal. The nonreduced end is composed of Rha, Ara and Gal. The main glycosidic link of SB_~1-1 has an α configuration.
基金Supported by National Natural Science Foundation of China(No.2 0 1710 10 ) .
文摘A novel compound, (HGly) 4[HPMo 12 O 40 ] 2·22H 2O, was synthesized and characterized by means of elemental analysis, IR and X ray diffraction. The compound crystallized in a monoclinic space group Cc with a =4 0060(0 8) nm, b =1 2527(0 3) nm, c =1 9930(0 4) nm, β =96 36(3)°, V =9 940(3) nm 3, Z =2, R 1=0 0576, wR 2 =0 1746. The anti tumor activity of this compound was tested in two human tumor cell lines in vitro .
基金Under the auspices of the National Natural Science Foundation of China (No. 40371039)
文摘This paper introduces a new concept of community-based ecotourism (CBET) that originated in foreign countries. Then it analyzes the significance of CBET development in nature reserve (NR). The authors think that community participation is the evitable choice of nature reserve′s conservation and development. CBET, as the self-improved model of ecotourism, can promote tourism community sustainable development. Based on the stakeholder analysis of CBET in NRs, this paper addresses the reality, especially the problem of CBET development in NRs of China. In order to develop CBET in NRs of China, this paper takes some suggestions to promote the community participation: 1)gradual political empowerment, 2) deep level economic incentive, 3) widespread educational support, 4) impartial distribution of community benefits, and 5) stakeholders cooperation.
文摘The ecological series of soil animals under the broad-leaved and pine mix ed forest in Darlidai Mountain was studied.Seven sample plots were selected according to different altitude gradients,which belong to dif ferent vegeta-tion types.By investigating and analyzing soil animals in every sample p lot it is found that there are 45group s and 1956individuals,which are involved in 3phylums,7classes,16orders,respectively.The altitude is a key factor which af-fects ecological series of soil anim als.Both the groups and individuals of soil animals increase with altitu de increasing under certain conditions,which con trastes with ordinary cases,resulting from special micro-climate in studied area.The groups and individuls of soil animals are the most under the broad-leaved and pine forest on the top of the mount ain,and the least under Picea-Abies forest in the foot of the mountain.
基金Supported by the National Natural Science Foundation of China(No.2 0 1710 10 )
文摘A new compound, (C 6H 6N 3) 7(PMo Ⅵ 12 O 40 )(PMo ⅤMo Ⅵ 11 O 40 )·2CH 3CH 2OH·5H 2O, was synthesized and characterized by means of elemental analyses, IR spectroscopy, 1H NMR spectroscopy and single crystal \{X ray\} diffraction. This is the first example of benzotriazole polyoxometalates species. The compound crystallized in a triclinic space group P 1 with a =1 8378(4) nm, b =1 9078(4) nm, c =2 1037 (4) nm, α =\{63 41(3)°\}, β =64 31(3)°, γ =68 38(3)°, V =5 803(2) nm 3, Z =2, R 1=0 0486, wR 2=0 1357. The X ray crystallographic study showed that the crystal structure was constructed by electrostatic interactions and hydrogen bonds between dodecamolybdophosphorate anions and protonated benzotriazole cations. The electrochemical behavior and the reduction of nitrite and hydrogen peroxide electrocatalyzed by the title compound were studied.
文摘The main purpose of this study is to give evaluation of ecological services of Jilin Province, Northeast China. To take this value into decision-making and GDP accounting system is considered to be one of the economic solutions for ecological problems. The evaluation is based on the methods proposed by COSTANZA et al., and some modifications about unit value of forest and cropland system were made according to the real characters of ecosystem, climate, natural conditions etc., in Jilin Province. Total value of ecosystem services is about 554.404x10(9) yuan(RMB)/a, which is about 4.9 times of GDP of the corresponding period. The results of this study could be used as a fundamental work for the construction of ecological province, which was carried out from 2001, and could provide ecological information for decision-making. Furthermore, the necessities for the further studies on the evaluation of ecological services and natural capital were discussed.
基金Department of Science & Technology of Jilin Province No.1999010
文摘The sandy land of the western part of Jilin Province is located in the ecotone of semi-humid and semi-arid area in the temperate zone of China. The sandy desertification has widely spread in the region because of the vulnerable natural conditions and the unreasonable human activity; as a result of this, the precious land resources and the economic development in the area have been seriously impacted. In this paper, the sandy land ecologic environment geographic information system is established based on the multi-spectral, multi-temporal Landsat TM images and field investigation. The comprehensive indexes of sandy desertification extent assessment which include vegetation degradation, wind erosion extent and soil depth are presented to classify the sandy land in western Jilin into three levels--slight, moderate and severe sandy desertification with the support of GIS platform. The results demonstrate that the sandy desertification has been partly controlled in the past twenty years, except some small sites. However, this doesn't necessarily mean that there is nothing for more concern. The two main causes of sandy desertification have not been eliminated yet, one is its natural factor, especially the physical and chemical characters of sandy soil and dry climate; another is the immoderate economic activity of human being that has highly accelerated the sandy desertification process.
文摘The essential oil of Schisandra Chinensis(Turc z.) Baill was extracted and analyzed. The essential oil was obtained in a 1.8%(mL/100 g material) yield. Forty eight compounds were isolated and characterized from the oil. The results show that the content(20.42%) of β -pinene of naturally essential oil is the highest among the components of the oil,which has laid a foundation for the futher development and application of the stems of Schisandra Chinensis(Turc z.) Baill .
文摘dinitrotoluene(2,4 DNT), 2,6 dinitrotoluene(2,6 DNT) and 4 nitrotoluene(4 NT) are typical pollutants in the Songhua River of Northeast China. Sertoli/germ cell cocultures and single cell gel electrophoresis(SCGE) are applied to investigate whether they have genotoxicity on DNA damage of germ cell of Kunming male rat. The results showed that all three nitrotoluene compounds tested could induce DNA single strand breaks of the germ cell. A significant relationship is found between logarithm dose and the degree of DNA damage, which implies that 2,4 DNT, 2,6 DNT and 4 NT have genotoxicity and can induce the germ cell DNA strand to break in vitro.
