Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province...Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province.The results show that soils near sewer outlet,sewer channel and in control area are averaged 2 239.5,995.33 and 104.9 mg/kg,respectively.The total Cr has a relative accumulation in soil depth of 200-400 mm near the sewer outlet,mainly enriches in the surface layer(0-200 mm) near the sewer channel and decreases gradually in unpolluted soils.The differential concentration level of enrichment between layers is little.The results also indicate that the three vegetables of celery,lettuce and Chinese cabbage are able to convert the potentially toxic Cr(Ⅵ) species into the non-toxic Cr(Ⅲ) species,and the chromium contents in the edible parts of the vegetables are averaged 11.95 mg/kg.The transfer factors of the three vegetables follow the order:Chinese cabbage lettuce celery.The estimated total daily intake of chromium substantially exceeds the dietary allowable value,which may pose health risks to local population.展开更多
In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When...In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When we compare these numerical tests, the results show that the main factors, affecting the heat transfer range are the thermal properties of the surrounding earth, the initial ground temperature and the temperature in the tunnel. The heat transfer coefficient between air and linings has little effect on the temperature distribution around the tunnel. The current results can provide a reference for improving the thermal environment in subways and optimizing the design of subwav ventilation and air conditioning.展开更多
Experiments and simulations on flow and heat transfer behavior of Therminol-55 liquid phase heat transfer fluid have been conducted in a ribbed tube with the outer diameter and inner diameter 25.0 and 20.0 mm,pitch an...Experiments and simulations on flow and heat transfer behavior of Therminol-55 liquid phase heat transfer fluid have been conducted in a ribbed tube with the outer diameter and inner diameter 25.0 and 20.0 mm,pitch and rib height of 4.5 and 1.0 mm.respectively.Experimental results show that the heat transfer and thermal performance of Therminol-55 liquid phase heat transfer fluid in the ribbed tube are considerably improved compared to those of the smooth tube.The Nusselt number increase with the increase of Reynolds number.The increase in heat transfer rate of the ribbed tube has a mean value of 2.24 times.Also,the pressure drop results reveal that the average friction factor of the ribbed tube is in a range of 2.4 and 2.8 times over the smooth tube.Numerical simulations of three-dimensional flow behavior of Therminol-55 liquid phase heat transfer fluid are carried out using three different turbulence models in the ribbed tube.The numerical results show that the heat transfer of ribbed tube is improved because vortices are generated behind ribs,which produce some disruptions to fluid flow and enhance heat transfer compared with smooth tube.The numerical results prove that the ribbed tube can improve heat transfer and fluid flow performances of Therminol liquid phase heat transfer fluid.展开更多
In this paper, it is offered to use the method of modulated reflection for the measurementof complex transfer factor of a radome wall on various sites of its surface. The circuit of equipmentallowed to carry out of su...In this paper, it is offered to use the method of modulated reflection for the measurementof complex transfer factor of a radome wall on various sites of its surface. The circuit of equipmentallowed to carry out of such measurement is given. The advantage of the given method in comparisonwith measurements on a gleam is shown. The results of the experimental research are given and theestimation of the accuracy of proposed method is considered.展开更多
[ Objective] To extract non-specific transfer factors (TFs) from goose spleens and to detect the activity of the extracts. [Methodl The non-specific TFs were extracted crudely from goose spleens using the dialysis m...[ Objective] To extract non-specific transfer factors (TFs) from goose spleens and to detect the activity of the extracts. [Methodl The non-specific TFs were extracted crudely from goose spleens using the dialysis method, and the effects of the extracts on immunity were studied. [ Result] The extracts of goose TFs were transparent, light yellow and non-toxic. The extracts were at pH 6.72 and did not contain higher molecular weight proteins. The concentration of minor polypeptides was 23.78 ug/ml. The results of immunization test showed that the level of antibodies was higher in the geese inoculated with the inactivated vaccine against infections serositis and the extracts of TFs than in the control geese injected with normal saline. In addition, the level of antibodies was significantly higher in the geese only inoculated with inactivated vaccine than in the control geese. The results showed that the extracts of TFs from goose spleens could enhance immunity to a certain extent. [ Conclusion] The study pro- vides a theoretical basis and technical reference for further researches on the biological activity of non-specific TFs from goose spleens as well as for application of the extracts.展开更多
A new method is presented for getting the general thermal response factors and z-transfer functioncoefficients of a room by synthesizing them from the thermal response factors of different parts of the thermalinsulati...A new method is presented for getting the general thermal response factors and z-transfer functioncoefficients of a room by synthesizing them from the thermal response factors of different parts of the thermalinsulation structure. How to use the general thermal response factors and z-transfer function coefficients toca1culate the indoor air temperature variation directly is also studied. It is shown through practical use that it iseasy to program with the methods presented in this paper and the calculated results are reliable.展开更多
The activity concentrations of radionuclides, absorbed dose rate, excess lifetime cancer risk, and soil-to-plant transfer factor have been evaluated in soil and crop samples from Jalingo and Wukari Local Government Ar...The activity concentrations of radionuclides, absorbed dose rate, excess lifetime cancer risk, and soil-to-plant transfer factor have been evaluated in soil and crop samples from Jalingo and Wukari Local Government Area of Taraba State, Nigeria. The activity concentrations were determined with the aid of High Purity Germanium detector. The absorbed dose and excess lifetime cancer risk were evaluated and forecasted for 60 years using the ResRad off-site model. The average activity concentration of <sup>40</sup>K, <sup>232</sup>Th, and <sup>238</sup>U in the soil samples were 633.13, 141.15, and 71.20 Bq·kg<sup>-1</sup> respectively, for the Jalingo study area, and while that of the Wukari study area was;199.21, 87.23, and 25.37 Bq·kg<sup>-1</sup> respectively. The average soil-to-plant transfer factors for <sup>40</sup>K, <sup>232</sup>Th, and <sup>238</sup>U were 0.51, 0.10, and 0.27 respectively for the Jalingo study area while that of Wukari are 0.40, 0.57, and 0.74 respectively. The mean annual effective dose equivalent for the study area is higher than the world average of 0.07 mS·vy<sup>-1</sup>. The excess lifetime cancer risk for the study areas has values that are higher than the safety limit. The ResRed model showed that direct radiation from the crops is the major contributor to excess cancer risk among other pathways. The radiological hazard indices reveal health risks to farmers, especially in the Jalingo area.展开更多
Purpose: The process of scientific literature use can be regarded as that of knowledge transfer. With the help of the knowledge transfer theory and data from scientific literature databases, we explored the behavior o...Purpose: The process of scientific literature use can be regarded as that of knowledge transfer. With the help of the knowledge transfer theory and data from scientific literature databases, we explored the behavior of scientific researchers during their scholarly communication, and studied the factors that influenced the behavior of researchers under network environment. Design/methodology/approach: Based on the literature databases of CNKI, Elsevier Science Direct and Springer Link, we used the knowledge transfer theory to construct a model for describing the scholarly communication process, which attempts to find out factors that may influence the communication behavior of researchers. With a focus laid on the absorption behavior of researchers during the knowledge acceptance process, we defined the independent variables of the model and proposed hypotheses on the basis of a comprehensive literature study. Afterwards, college students were invited to participate in a questionnaire survey, which was designed to prove our research model and hypotheses.Findings: Our results showed that during the scholarly communication, it is not the professional knowledge, but the ability and willingness for knowledge acceptance, organizations’ importance and internal atmosphere as well as knowledge authority and relevance that have played a positive significant role in the knowledge transfer performance. In addition, our distance indicators showed that knowledge distance and knowledge transfer performance have significant negative correlations. Research limitations: This study is mainly based on a questionnaire survey of college students, which may limit the generalization of our research results. In addition, more resource types need be considered for further studies.Practical implications: Under network environment, scholarly communication performance based on knowledge transfer theory could greatly contribute to the enrichment of the contentof the knowledge transfer theory, and stretch out the range of the field. In addition, our result could help commercial scientific database providers to learn more about the users’ needs, which would not only benefit both scientific communities and content providers, but also promote scholarly communication effectively. Originality/value: Compared with existing researches which mainly emphasized the model construction of scholarly communication, our study focused the knowledge relevance during the scholarly communication and influence factors that impacted on the performance of knowledge acceptance under the network environment, which could provide helpful guides for further studies.展开更多
The aim of this study is to determine the transfer factor soil-to-plant and to assess the concentration level of natural and artificial radionuclide (238U, 226Ra, 228Ra, 232Th, 40K and 137Cs) in samples from Saluga an...The aim of this study is to determine the transfer factor soil-to-plant and to assess the concentration level of natural and artificial radionuclide (238U, 226Ra, 228Ra, 232Th, 40K and 137Cs) in samples from Saluga and Ghazal Protectorate area in Aswan, Egypt, by using High Pure Germanium detector (HPGe) Environmental Radioactivity Measurements Labrotary in faculty of science Qena. Reported values for natural radionuclides ranged from 8.81 ± 0.64 to 28.88 ± 2.10, from 6.98 ± 0.51 to 26.01 ± 1.89, from 12.29 ± 0.89 to 33.32 ± 2.43, from 12.53 ± 0.91 to 32.81 ± 2.39 and from 383.90 ± 27.95 to 711.98 ± 51.83 Bq.kg-1 for 238U, 226Ra, 228Ra, 232Th and 40K, respectively. 137Cs activity concentration was found to be in the range from 0.36 ± 0.03 to 9.73 ± 0.71 Bq.kg-1 and was calculated through transfer factor TF reported in this article.展开更多
The numerous factors influencing the air-sea carbon dioxide(CO_2) transfer velocity have been discussed for many years, yet the contributions of various factors have undergone little quantitative estimation. To bett...The numerous factors influencing the air-sea carbon dioxide(CO_2) transfer velocity have been discussed for many years, yet the contributions of various factors have undergone little quantitative estimation. To better understand the mechanism of air-sea transfer, the effects of different factors are discussed on the air-sea transfer velocity and the various parametric models describing the phenomenon are classified and compared.Then, based on GAS EX-98 and ASGAMAGE data, wind models are evaluated and the effects of some factors are discussed quantitatively, including bubbles, waves, wind and so on by considering their interaction through a piecewise average approach. It is found that the air-sea CO_2 transfer velocity is not only the function of the wind speed, but is also affected by bubbles, wave parameters and other factors. Stepwise and linear regressions are used. When considering the wind speed, bubbles mediated and the significant wave height, the root mean square error is reduced from 34.53 cm/h to 16.96 cm/h. Discussing the various factors quantitatively can be useful in future assessments of a large spatial scale and long-term air-sea CO_2 flux and global change.展开更多
The radiative capture reaction plays an important role in nuclear astrophysics. We have indirectly measured the astrophysical S(E) factors for some proton capture reactions and reaction rates for several neutron cap...The radiative capture reaction plays an important role in nuclear astrophysics. We have indirectly measured the astrophysical S(E) factors for some proton capture reactions and reaction rates for several neutron capture reactions with one nucleon transfer reactions at HI-13 tandem accelerator in recent years. Some of them are compiled into IAEA EXFOR database and JINA REACLIB project, and used in the network calculations of Big Bang nucleosynthesis and type-I X-ray bursts.展开更多
Accumulation of heavy metals in agricultural soils is instigated by industrial and other human activities such as mining,smelting,cement-pollution,energy and fuel production,power transmission,traffic activities,inten...Accumulation of heavy metals in agricultural soils is instigated by industrial and other human activities such as mining,smelting,cement-pollution,energy and fuel production,power transmission,traffic activities,intensive agriculture,sludge dumping and melting operations.Plants received heavy metals from soils through ionic exchange,redox reactions,precipitation-dissolution,and so on,which implies that the solubility of trace elements based on factors like minerals in the soil(carbonates,oxide,hydroxide etc.),soil organic matter(humic acids,fulvic acids,polysaccharides and organic acids),soil pH,redox potential,content,nutrient balance,other trace elements concentration in soil,physical and mechanical characteristics of soil,soil temperature and humidity,and so on.In this study,the soil-edible plant and soil-water Transfer Factor(TF)for various metals showed that the TF values differed slightly between the locations.On soil-edible plant transfer,the mean TF for different heavy metals in soil-edible plants decreased in the following order:As(0.6)mg/kg>Cd(0.1)mg/kg>Cr(0.06)mg/kg>Pb(0.003)mg/kg>Ni(0.001)mg/kg.The total TF for different locations decreases in the following order:Barkin Ladi(1.0)mg/kg>Jos South and Jos East(0.7)mg/kg>Bassa and Mangu(0.6)mg/kg.On soil-water transfer,the mean TF for different heavy metals in soil-edible plants decreased in the following order:Cd(0.001)mg/L>As(0.0007)mg/L>Cr(0.0005)mg/L>Pb(0.0001)mg/L and Ni(0.0001)mg/L.The total TF for different locations decreases in the following order:Jos South(0.003)mg/kg>Barkin Ladi,Bassa,Jos East and Mangu(0.002)mg/kg.Based on the findings of this study,it can be concluded that the water and edible plants in the study area are good for public consumption,even though,regular checking of heavy metals in the study area is recommended.展开更多
Based on the questionnaire survey of land transfer in Suixian County and Zengdu District of Hubei Province,this paper analyzes the factors that affect farmers' willingness to transfer land from regional characteri...Based on the questionnaire survey of land transfer in Suixian County and Zengdu District of Hubei Province,this paper analyzes the factors that affect farmers' willingness to transfer land from regional characteristics,individual characteristics of farmers,and household characteristics of farmers. The survey results show that farmers' willingness to transfer land is affected by many factors. And the level of regional economic development,farmer's age,educational level,family population and income are the important factors influencing farmers' land transfer.The key factor influencing the willingness to transfer out land is farmers' high reliance on land security function,and the main reasons for farmers' land transfer-in lie in low agricultural comparative benefits and immature land transfer market.展开更多
The experiments of large consumers direct power trading is conducting in china nationwide, and it’s important to the reform of electricity market. To compensated efficiencies in security correction of large consumers...The experiments of large consumers direct power trading is conducting in china nationwide, and it’s important to the reform of electricity market. To compensated efficiencies in security correction of large consumers direct power trading, a novel security correction method based on DC power transfer distribution factor was proposed. Using the presented method to comply security correction, all the transactions that satisfy the specific requirements of maximizing social welfare are able to enter security correction process, and when the power of transmission line is out of limit, this method avoid the transaction which causes this problem is abandoned directly by introducing supplement transactions. The simulation has shown that the proposed security correction method of large consumers direct power trading based on DC power transfer distribution factor is effective.展开更多
Knowledge transfer model of software process improvement (SPI) and the conceptual framework of influencing factors are established. The model includes five elements which are knowledge of transfer, sources of knowledg...Knowledge transfer model of software process improvement (SPI) and the conceptual framework of influencing factors are established. The model includes five elements which are knowledge of transfer, sources of knowledge, recipients of knowledge, relationship of transfer parties, and the environment of transfer. The conceptual framework includes ten key factors which are ambiguity, systematism, transfer willingness, capacity of impartation, capacity of absorption, incen-tive mechanism, culture, technical support, trust and knowledge distance. The research hypothesis is put forward. Em-pirical study concludes that the trust relationship among SPI staffs has the greatest influence on knowledge transfer, and organizational incentive mechanism can produce positive effect to knowledge transfer of SPI. Finally, some sug-gestions are put forward to improve the knowledge transfer of SPI: establishing a rational incentive mechanism, exe-cuting some necessary training to transfer parties and using software benchmarking.展开更多
The effect of transforming growth factor β 1 (TGF β 1 ) gene transfection on the proliferation of bone marrow derived mesenchymal stem cells (MSC S ) and the mechanism was investigated to provide basi...The effect of transforming growth factor β 1 (TGF β 1 ) gene transfection on the proliferation of bone marrow derived mesenchymal stem cells (MSC S ) and the mechanism was investigated to provide basis for accelerating articular cartilage repairing using molecular tissue engineering technology. TGF β 1 gene at different doses was transduced into the rat bone marrow derived MSCs to examine the effects of TGF β 1 gene transfection on MSCs DNA synthesis, cell cycle kinetics and the expression of proliferating cell nuclear antigen (PCNA). The results showed that 3 μl lipofectamine mediated 1 μg TGF β 1 gene transfection could effectively promote the proliferation of MSCs best; Under this condition (DNA/Lipofectamine=1μg/3μl), flow cytometry and immunohistochemical analyses revealed a significant increase in the 3 H incorporation, DNA content in S phase and the expression of PCNA. Transfection of gene encoding TGF β 1 could induce the cells at G0/G1 phase to S1 phase, modulate the replication of DNA through the enhancement of the PCNA expression, increase the content of DNA at S1 phase and promote the proliferation of MSCs. This new molecular tissue engineering approach could be of potential benefit to enhance the repair of damaged articular cartilage, especially those caused by degenerative joint diseases.展开更多
To examine the ability of intrastriatal gene transfer of vascular endothelial growth factor 165 mediated by adenoviral vector to rescue dopaminergic neurons in a rat model of Parkinson's disease (PD), we constructe...To examine the ability of intrastriatal gene transfer of vascular endothelial growth factor 165 mediated by adenoviral vector to rescue dopaminergic neurons in a rat model of Parkinson's disease (PD), we constructed recombinant replication-deficent adenoviral vectors carrying the gene of VEGF165 (Ad-VEGF), and injected Ad-VEGF (or Ad-LacZ and PBS as controls) into the striatum of rats 7 days after the lesion by 6-hydroxydopamine. The rat rotational behavior analysis and tyrosine hydroxylase (TH) immunohistochemistry were performed to assess the change of dopaminergic neurons. Our results showed that the rats receiving Ad-VEGF injection displayed a significant improvement in apomorphine-induced rotational behavior and a significant preservation of TH-positive neurons and fibers compared with control animals, It is concluded that intrastriatal gene transfer by Ad-VEGF may rescue the dopaminergic neurons from degeneration in a rat model of PD.展开更多
基金Project (2009ZX07212-001-01) supported by the Key Project of National Natural Science Foundation for Water Pollution Control and RemediationProject (50925417) supported by the National Funds for Distinguished Young Scientists+1 种基金Project (50830301) supported by the National Natural Science Foundation of ChinaProject (51074191) supported by the National Natural Science Foundation of China
文摘Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province.The results show that soils near sewer outlet,sewer channel and in control area are averaged 2 239.5,995.33 and 104.9 mg/kg,respectively.The total Cr has a relative accumulation in soil depth of 200-400 mm near the sewer outlet,mainly enriches in the surface layer(0-200 mm) near the sewer channel and decreases gradually in unpolluted soils.The differential concentration level of enrichment between layers is little.The results also indicate that the three vegetables of celery,lettuce and Chinese cabbage are able to convert the potentially toxic Cr(Ⅵ) species into the non-toxic Cr(Ⅲ) species,and the chromium contents in the edible parts of the vegetables are averaged 11.95 mg/kg.The transfer factors of the three vegetables follow the order:Chinese cabbage lettuce celery.The estimated total daily intake of chromium substantially exceeds the dietary allowable value,which may pose health risks to local population.
基金Projects BK2007145 supported by the Jiangsu Natural Science Foundation of China NCET-04-0454 by the Program for New Century Excellent Talentsin Universities
文摘In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When we compare these numerical tests, the results show that the main factors, affecting the heat transfer range are the thermal properties of the surrounding earth, the initial ground temperature and the temperature in the tunnel. The heat transfer coefficient between air and linings has little effect on the temperature distribution around the tunnel. The current results can provide a reference for improving the thermal environment in subways and optimizing the design of subwav ventilation and air conditioning.
基金Supported by the National Natural Science Foundation of China(11472093 and21276056)
文摘Experiments and simulations on flow and heat transfer behavior of Therminol-55 liquid phase heat transfer fluid have been conducted in a ribbed tube with the outer diameter and inner diameter 25.0 and 20.0 mm,pitch and rib height of 4.5 and 1.0 mm.respectively.Experimental results show that the heat transfer and thermal performance of Therminol-55 liquid phase heat transfer fluid in the ribbed tube are considerably improved compared to those of the smooth tube.The Nusselt number increase with the increase of Reynolds number.The increase in heat transfer rate of the ribbed tube has a mean value of 2.24 times.Also,the pressure drop results reveal that the average friction factor of the ribbed tube is in a range of 2.4 and 2.8 times over the smooth tube.Numerical simulations of three-dimensional flow behavior of Therminol-55 liquid phase heat transfer fluid are carried out using three different turbulence models in the ribbed tube.The numerical results show that the heat transfer of ribbed tube is improved because vortices are generated behind ribs,which produce some disruptions to fluid flow and enhance heat transfer compared with smooth tube.The numerical results prove that the ribbed tube can improve heat transfer and fluid flow performances of Therminol liquid phase heat transfer fluid.
文摘In this paper, it is offered to use the method of modulated reflection for the measurementof complex transfer factor of a radome wall on various sites of its surface. The circuit of equipmentallowed to carry out of such measurement is given. The advantage of the given method in comparisonwith measurements on a gleam is shown. The results of the experimental research are given and theestimation of the accuracy of proposed method is considered.
基金funded by the Innovation Fund Project for College Students of Rongchang Campus of Southwest University,Chongqing Basic Research program ( 2008BB5243)the Fundamental Research Funds for the Central Universities( XDJK2010C093)
文摘[ Objective] To extract non-specific transfer factors (TFs) from goose spleens and to detect the activity of the extracts. [Methodl The non-specific TFs were extracted crudely from goose spleens using the dialysis method, and the effects of the extracts on immunity were studied. [ Result] The extracts of goose TFs were transparent, light yellow and non-toxic. The extracts were at pH 6.72 and did not contain higher molecular weight proteins. The concentration of minor polypeptides was 23.78 ug/ml. The results of immunization test showed that the level of antibodies was higher in the geese inoculated with the inactivated vaccine against infections serositis and the extracts of TFs than in the control geese injected with normal saline. In addition, the level of antibodies was significantly higher in the geese only inoculated with inactivated vaccine than in the control geese. The results showed that the extracts of TFs from goose spleens could enhance immunity to a certain extent. [ Conclusion] The study pro- vides a theoretical basis and technical reference for further researches on the biological activity of non-specific TFs from goose spleens as well as for application of the extracts.
文摘A new method is presented for getting the general thermal response factors and z-transfer functioncoefficients of a room by synthesizing them from the thermal response factors of different parts of the thermalinsulation structure. How to use the general thermal response factors and z-transfer function coefficients toca1culate the indoor air temperature variation directly is also studied. It is shown through practical use that it iseasy to program with the methods presented in this paper and the calculated results are reliable.
文摘The activity concentrations of radionuclides, absorbed dose rate, excess lifetime cancer risk, and soil-to-plant transfer factor have been evaluated in soil and crop samples from Jalingo and Wukari Local Government Area of Taraba State, Nigeria. The activity concentrations were determined with the aid of High Purity Germanium detector. The absorbed dose and excess lifetime cancer risk were evaluated and forecasted for 60 years using the ResRad off-site model. The average activity concentration of <sup>40</sup>K, <sup>232</sup>Th, and <sup>238</sup>U in the soil samples were 633.13, 141.15, and 71.20 Bq·kg<sup>-1</sup> respectively, for the Jalingo study area, and while that of the Wukari study area was;199.21, 87.23, and 25.37 Bq·kg<sup>-1</sup> respectively. The average soil-to-plant transfer factors for <sup>40</sup>K, <sup>232</sup>Th, and <sup>238</sup>U were 0.51, 0.10, and 0.27 respectively for the Jalingo study area while that of Wukari are 0.40, 0.57, and 0.74 respectively. The mean annual effective dose equivalent for the study area is higher than the world average of 0.07 mS·vy<sup>-1</sup>. The excess lifetime cancer risk for the study areas has values that are higher than the safety limit. The ResRed model showed that direct radiation from the crops is the major contributor to excess cancer risk among other pathways. The radiological hazard indices reveal health risks to farmers, especially in the Jalingo area.
基金jointly supported by the National Natural Science Foundation of China(Grant No:71373124)Assemble Technology Infrastructure Projects(Grant No.QTQNJ20121QB04)
文摘Purpose: The process of scientific literature use can be regarded as that of knowledge transfer. With the help of the knowledge transfer theory and data from scientific literature databases, we explored the behavior of scientific researchers during their scholarly communication, and studied the factors that influenced the behavior of researchers under network environment. Design/methodology/approach: Based on the literature databases of CNKI, Elsevier Science Direct and Springer Link, we used the knowledge transfer theory to construct a model for describing the scholarly communication process, which attempts to find out factors that may influence the communication behavior of researchers. With a focus laid on the absorption behavior of researchers during the knowledge acceptance process, we defined the independent variables of the model and proposed hypotheses on the basis of a comprehensive literature study. Afterwards, college students were invited to participate in a questionnaire survey, which was designed to prove our research model and hypotheses.Findings: Our results showed that during the scholarly communication, it is not the professional knowledge, but the ability and willingness for knowledge acceptance, organizations’ importance and internal atmosphere as well as knowledge authority and relevance that have played a positive significant role in the knowledge transfer performance. In addition, our distance indicators showed that knowledge distance and knowledge transfer performance have significant negative correlations. Research limitations: This study is mainly based on a questionnaire survey of college students, which may limit the generalization of our research results. In addition, more resource types need be considered for further studies.Practical implications: Under network environment, scholarly communication performance based on knowledge transfer theory could greatly contribute to the enrichment of the contentof the knowledge transfer theory, and stretch out the range of the field. In addition, our result could help commercial scientific database providers to learn more about the users’ needs, which would not only benefit both scientific communities and content providers, but also promote scholarly communication effectively. Originality/value: Compared with existing researches which mainly emphasized the model construction of scholarly communication, our study focused the knowledge relevance during the scholarly communication and influence factors that impacted on the performance of knowledge acceptance under the network environment, which could provide helpful guides for further studies.
文摘The aim of this study is to determine the transfer factor soil-to-plant and to assess the concentration level of natural and artificial radionuclide (238U, 226Ra, 228Ra, 232Th, 40K and 137Cs) in samples from Saluga and Ghazal Protectorate area in Aswan, Egypt, by using High Pure Germanium detector (HPGe) Environmental Radioactivity Measurements Labrotary in faculty of science Qena. Reported values for natural radionuclides ranged from 8.81 ± 0.64 to 28.88 ± 2.10, from 6.98 ± 0.51 to 26.01 ± 1.89, from 12.29 ± 0.89 to 33.32 ± 2.43, from 12.53 ± 0.91 to 32.81 ± 2.39 and from 383.90 ± 27.95 to 711.98 ± 51.83 Bq.kg-1 for 238U, 226Ra, 228Ra, 232Th and 40K, respectively. 137Cs activity concentration was found to be in the range from 0.36 ± 0.03 to 9.73 ± 0.71 Bq.kg-1 and was calculated through transfer factor TF reported in this article.
基金The Shanghai Sailing Program of Science and Technology Commission of Shanghai Municipality of China under contract No.14YF1410300the Special Fund for Basic Scientific Research Business of Central Public Research Institutes of 2015 of China under contract No.JG1503+3 种基金the Postdoctoral Research Projects in Zhejiang Province of China under contract No.BSH1502044the Shanghai Young University Teachers Training Support Plan of Shanghai Municipal Education Commission of China under contract Nos A1-2035-15-0021-11and ZZegd14015the 2014 Research Projects of Shanghai Second Polytechnic University of China under contract No.A01GY14GX33the Project Funded by the Local College Capacity Building Program of Science and Technology Commission of Shanghai Municipality of China under contract No.13230502000
文摘The numerous factors influencing the air-sea carbon dioxide(CO_2) transfer velocity have been discussed for many years, yet the contributions of various factors have undergone little quantitative estimation. To better understand the mechanism of air-sea transfer, the effects of different factors are discussed on the air-sea transfer velocity and the various parametric models describing the phenomenon are classified and compared.Then, based on GAS EX-98 and ASGAMAGE data, wind models are evaluated and the effects of some factors are discussed quantitatively, including bubbles, waves, wind and so on by considering their interaction through a piecewise average approach. It is found that the air-sea CO_2 transfer velocity is not only the function of the wind speed, but is also affected by bubbles, wave parameters and other factors. Stepwise and linear regressions are used. When considering the wind speed, bubbles mediated and the significant wave height, the root mean square error is reduced from 34.53 cm/h to 16.96 cm/h. Discussing the various factors quantitatively can be useful in future assessments of a large spatial scale and long-term air-sea CO_2 flux and global change.
基金supported by the National Basic Research Programme of China (No. 2007CB815003)National Natural Science Foundation of China(Nos. 10675173, 10705053, 10735100 and 11021504)
文摘The radiative capture reaction plays an important role in nuclear astrophysics. We have indirectly measured the astrophysical S(E) factors for some proton capture reactions and reaction rates for several neutron capture reactions with one nucleon transfer reactions at HI-13 tandem accelerator in recent years. Some of them are compiled into IAEA EXFOR database and JINA REACLIB project, and used in the network calculations of Big Bang nucleosynthesis and type-I X-ray bursts.
文摘Accumulation of heavy metals in agricultural soils is instigated by industrial and other human activities such as mining,smelting,cement-pollution,energy and fuel production,power transmission,traffic activities,intensive agriculture,sludge dumping and melting operations.Plants received heavy metals from soils through ionic exchange,redox reactions,precipitation-dissolution,and so on,which implies that the solubility of trace elements based on factors like minerals in the soil(carbonates,oxide,hydroxide etc.),soil organic matter(humic acids,fulvic acids,polysaccharides and organic acids),soil pH,redox potential,content,nutrient balance,other trace elements concentration in soil,physical and mechanical characteristics of soil,soil temperature and humidity,and so on.In this study,the soil-edible plant and soil-water Transfer Factor(TF)for various metals showed that the TF values differed slightly between the locations.On soil-edible plant transfer,the mean TF for different heavy metals in soil-edible plants decreased in the following order:As(0.6)mg/kg>Cd(0.1)mg/kg>Cr(0.06)mg/kg>Pb(0.003)mg/kg>Ni(0.001)mg/kg.The total TF for different locations decreases in the following order:Barkin Ladi(1.0)mg/kg>Jos South and Jos East(0.7)mg/kg>Bassa and Mangu(0.6)mg/kg.On soil-water transfer,the mean TF for different heavy metals in soil-edible plants decreased in the following order:Cd(0.001)mg/L>As(0.0007)mg/L>Cr(0.0005)mg/L>Pb(0.0001)mg/L and Ni(0.0001)mg/L.The total TF for different locations decreases in the following order:Jos South(0.003)mg/kg>Barkin Ladi,Bassa,Jos East and Mangu(0.002)mg/kg.Based on the findings of this study,it can be concluded that the water and edible plants in the study area are good for public consumption,even though,regular checking of heavy metals in the study area is recommended.
基金Supported by Social Science Fund Project of Yangtze University in 2015(2015csy007)
文摘Based on the questionnaire survey of land transfer in Suixian County and Zengdu District of Hubei Province,this paper analyzes the factors that affect farmers' willingness to transfer land from regional characteristics,individual characteristics of farmers,and household characteristics of farmers. The survey results show that farmers' willingness to transfer land is affected by many factors. And the level of regional economic development,farmer's age,educational level,family population and income are the important factors influencing farmers' land transfer.The key factor influencing the willingness to transfer out land is farmers' high reliance on land security function,and the main reasons for farmers' land transfer-in lie in low agricultural comparative benefits and immature land transfer market.
文摘The experiments of large consumers direct power trading is conducting in china nationwide, and it’s important to the reform of electricity market. To compensated efficiencies in security correction of large consumers direct power trading, a novel security correction method based on DC power transfer distribution factor was proposed. Using the presented method to comply security correction, all the transactions that satisfy the specific requirements of maximizing social welfare are able to enter security correction process, and when the power of transmission line is out of limit, this method avoid the transaction which causes this problem is abandoned directly by introducing supplement transactions. The simulation has shown that the proposed security correction method of large consumers direct power trading based on DC power transfer distribution factor is effective.
文摘Knowledge transfer model of software process improvement (SPI) and the conceptual framework of influencing factors are established. The model includes five elements which are knowledge of transfer, sources of knowledge, recipients of knowledge, relationship of transfer parties, and the environment of transfer. The conceptual framework includes ten key factors which are ambiguity, systematism, transfer willingness, capacity of impartation, capacity of absorption, incen-tive mechanism, culture, technical support, trust and knowledge distance. The research hypothesis is put forward. Em-pirical study concludes that the trust relationship among SPI staffs has the greatest influence on knowledge transfer, and organizational incentive mechanism can produce positive effect to knowledge transfer of SPI. Finally, some sug-gestions are put forward to improve the knowledge transfer of SPI: establishing a rational incentive mechanism, exe-cuting some necessary training to transfer parties and using software benchmarking.
基金This project was supported by a grant from NationalNatural Science Foundation of China (No. 30 170 2 70 )
文摘The effect of transforming growth factor β 1 (TGF β 1 ) gene transfection on the proliferation of bone marrow derived mesenchymal stem cells (MSC S ) and the mechanism was investigated to provide basis for accelerating articular cartilage repairing using molecular tissue engineering technology. TGF β 1 gene at different doses was transduced into the rat bone marrow derived MSCs to examine the effects of TGF β 1 gene transfection on MSCs DNA synthesis, cell cycle kinetics and the expression of proliferating cell nuclear antigen (PCNA). The results showed that 3 μl lipofectamine mediated 1 μg TGF β 1 gene transfection could effectively promote the proliferation of MSCs best; Under this condition (DNA/Lipofectamine=1μg/3μl), flow cytometry and immunohistochemical analyses revealed a significant increase in the 3 H incorporation, DNA content in S phase and the expression of PCNA. Transfection of gene encoding TGF β 1 could induce the cells at G0/G1 phase to S1 phase, modulate the replication of DNA through the enhancement of the PCNA expression, increase the content of DNA at S1 phase and promote the proliferation of MSCs. This new molecular tissue engineering approach could be of potential benefit to enhance the repair of damaged articular cartilage, especially those caused by degenerative joint diseases.
文摘To examine the ability of intrastriatal gene transfer of vascular endothelial growth factor 165 mediated by adenoviral vector to rescue dopaminergic neurons in a rat model of Parkinson's disease (PD), we constructed recombinant replication-deficent adenoviral vectors carrying the gene of VEGF165 (Ad-VEGF), and injected Ad-VEGF (or Ad-LacZ and PBS as controls) into the striatum of rats 7 days after the lesion by 6-hydroxydopamine. The rat rotational behavior analysis and tyrosine hydroxylase (TH) immunohistochemistry were performed to assess the change of dopaminergic neurons. Our results showed that the rats receiving Ad-VEGF injection displayed a significant improvement in apomorphine-induced rotational behavior and a significant preservation of TH-positive neurons and fibers compared with control animals, It is concluded that intrastriatal gene transfer by Ad-VEGF may rescue the dopaminergic neurons from degeneration in a rat model of PD.