Broken coal structure and low permeability are the main reasons for the difficult production of coalbed methane(CBM)in broken-soft coal seams.In this paper,No.8 coal seam in the Luling Mine of the Huaibei Coal Field w...Broken coal structure and low permeability are the main reasons for the difficult production of coalbed methane(CBM)in broken-soft coal seams.In this paper,No.8 coal seam in the Luling Mine of the Huaibei Coal Field was taken as an example to study the way to improve CBM production of broken-soft coal reservoirs.First,drilling,fracturing and production of horizontal wells were considered comprehensively.Then,based on the idea of exploiting CBM through horizontal wells in roof strata close to the broken-soft coal seams,the propagation laws of fractures created by layer-penetrating fracturing of horizontal wells in roof strata were studied,and accordingly the location of horizontal well was optimized.Finally,the CBM horizontal well exploitation technology for the roof strata close to coal seams was developed and tested on site.And the following research results were obtained.First,the vertical fractures created during layer-penetrating fracturing of horizontal wells in roof strata can propagate from the roof strata with high stress values downward to the coal seam with low stress values.In addition,the location of horizontal well has an important influence on the effect of layer-penetrating fracturing.The closer the horizontal well is to the coal seam,the better the fracture propagation effect of layer-penetrating fracturing.Second,the horizontal well should be arranged in the roof strata 1.5 m away from the top of coal seam,so that fracturing stimulation requirements of horizontal wells in roof strata can be satisfied to the uttermost.Third,three key technologies are formed,including the“high-quality,fast and safe”drilling technology,the deep-penetration oriented perforating technology and the“large displacement,large scale,high pad ratio and moderate proppant concentration”active water fracturing technology.Fourth,the gas production with this technology in engineering practice is remarkable.In conclusion,the CBM development technology of horizontal wells in roof strata close to broken-soft coal seams is feasible.The research results provide a new technical method for the development of CBM in broken-soft coal seams.展开更多
With the rapid development of e-commerce and big data, online work demand is higher and higher, need to website design is more and more talents. You need to improve students comprehensive practice ability in teaching,...With the rapid development of e-commerce and big data, online work demand is higher and higher, need to website design is more and more talents. You need to improve students comprehensive practice ability in teaching, let the students not only master knowledge, but also practice, can independently complete a complete project design. This paper takes a certain project as an example, and proposes a project-based task-driven teaching reform method, which can better improve the students comprehensive practical ability, and achieve the purpose of improving the teaching effect.展开更多
This study takes the patent information of China's electric agricultural machinery technology as the research object,and uses patent measurement analysis method and visual analysis tools to carry out statistical a...This study takes the patent information of China's electric agricultural machinery technology as the research object,and uses patent measurement analysis method and visual analysis tools to carry out statistical analysis and comparative research on the relevant patent information from the perspectives of annual patent applications,patent structure,technological key,main applicants,patent layout,technology lifecycle and so on.The research results show that China's electric agricultural machinery technology innovation is developing rapidly,and the patent categories are mainly utility model and invention patents,and the proportion of invention patents is lower than utility model patents.Universities are the most important innovation subjects in this field,and technology research and development focuses on IPC(international patent classification)subcategories such as A01C(seeding,fertilization),B60K(power,transmission),and A01D(harvesting.mowing).Jiangsu Province and Shandong Province rank the top 2 in the number of domestic patent applications,and the United States and Japan are the two countries with the most layout in China.At present,the growth of electric agricultural machinery technology is weak,but the new technology has strong features,there is no sign of maturity,and it does not have signs of technological aging and still has greater development potential.The results of the study can provide information reference for clarifying the status quo,characteristics and development trend of China's electric agricultural machinery technology innovation.展开更多
Super-heavy oil is a significant unconventional energy source,and more than 30 years of research have shown that steam-assisted gravity drainage(SAGD)technology is suitable for thick super-heavy oil reservoirs.Recentl...Super-heavy oil is a significant unconventional energy source,and more than 30 years of research have shown that steam-assisted gravity drainage(SAGD)technology is suitable for thick super-heavy oil reservoirs.Recently,more and more thin-layer super-heavy oil reservoirs have been discovered in China,while their deep buried depth and serous heterogeneity make the existing SAGD technology difficult to apply,so it is urgent to improve the existing SAGD technology for the thin-layer super-heavy oil.To this end,this paper focuses on the enlightenment of field application in SAGD technology.Firstly,based on typical SAGD field projects,the development history of SAGD technology in the world was reviewed,and the influence of reservoir physical properties on the application of SAGD technology in thin-layer superheavy oil reservoirs was analyzed.Secondly,the well pattern,wellbore structure,pre-heating,artificial lift,and monitor technique of SAGD were detailed described,and their adjustment direction was expounded for the development of thin-layer super-heavy oil reservoirs.Lastly,the gas-and solventassistant SAGD were comprehensively evaluated,and their application potential in thin-layer superheavy oil reservoirs was studied.The research results can provide theoretical guidance for the application of SAGD technology in thin-layer super-heavy oil reservoirs.展开更多
As decarbonization pressure on traditional fossil fuel-related industries gradually intensifies,CCUS has been increasingly incorporated into energy transition strategies by various oil companies.From a development opp...As decarbonization pressure on traditional fossil fuel-related industries gradually intensifies,CCUS has been increasingly incorporated into energy transition strategies by various oil companies.From a development opportunity perspective,oil companies possess four key advantages in developing the CCUS industry:exploration and development technology advantages;geological resource advantages;capital advantages;source-sink matching advantages.In terms of challenges,oil companies face numerous issues in developing the CCUS industry,including technological development,economic viability,and policy and legal aspects.At the national level,China’s oil companies should advocate for improving and optimizing relevant laws and regulations,enhancing the policy support system,incorporating CCUS into the carbon trading market,and strengthening top-level design and medium-to long-term planning;at the enterprise level,they should continuously advance full industrial chain technologies and reduce CCUS project operating costs,selectively participate in industrial segments that suit their capabilities,strengthen CCUS full industrial chain operational capabilities,and enhance talent development and strengthen international exchange and cooperation.展开更多
[Objective] This study aimed to provide references for the application of participatory monitoring and evaluation in the development of animal husbandry tech- nology. [Method] With the livelihood improvement program f...[Objective] This study aimed to provide references for the application of participatory monitoring and evaluation in the development of animal husbandry tech- nology. [Method] With the livelihood improvement program for agricultural and pas- toral area in northern Yunnan as the example, the development process of partici- patory animal husbandry was overviewed. And the monitoring and evaluation pro- cesses of participatory animal husbandry were introduced and analyzed. [Result] The monitoring and evaluation indicator system of participatory animal husbandry technol- ogy included 4 layers, namely technology, institutional system, personnel ability con- struction and effectiveness, and 11 third-level indicators, namely, technical characteristics, superiority-inferiority comparison, community and farmers, technical personnel, project personnel, economic indicators and social indicators. [Conclusion] This study provided the references for the application of participatory monitoring and evaluation in the development of animal husbandry technology.展开更多
Developing deep fragmented soft coalbed methane(CBM)can significantly enhance domestic natural gas supplies,reduce reliance on imported energy,and bolster national energy security.This manuscript provides a comprehens...Developing deep fragmented soft coalbed methane(CBM)can significantly enhance domestic natural gas supplies,reduce reliance on imported energy,and bolster national energy security.This manuscript provides a comprehensive review of commonly employed coalbed methane extraction technologies.It then delves into several critical issues in the current stage of CBM exploration and development in China,including the compatibility of existing technologies with CBM reservoirs,the characteristics and occurrence states of CBM reservoirs,critical desorption pressure,and gas generation mechanisms.Our research indicates that current CBM exploration and development technologies in China have reached an internationally advanced level,yet the industry is facing unprecedented challenges.Despite progress in low-permeability,high-value coal seams,significant breakthroughs have not been achieved in exploring other types of coal seams.For different coal reservoirs,integrated extraction technologies have been developed,such as surface pre-depressurisation and segmented hydraulic fracturing of coal seam roof strata.Additionally,techniques like large-scale volume fracturing in horizontal wells have been established,significantly enhancing reservoir stimulation effects and coalbed methane recovery rates.However,all of these technologies are fundamentally based on permeation.These technologies lack direct methods aimed at enhancing the diffusion rate of CBM,thereby failing to fully reflect the unique characteristics of CBM.Current CBM exploration and development theories and technologies are not universally applicable to all coal seams.They do not adequately account for the predominantly adsorbed state of CBM,and the complex and variable gas generation mechanisms further constrain CBM development in China.Finally,continuous exploration of new deep CBM exploration technologies is necessary.Integrating more effective reservoir stimulation technologies is essential to enhance technical adaptability concerning CBM reservoir characteristics,gas occurrence states,and gas generation mechanisms,ultimately achieving efficient CBM development.We conclude that while China possesses a substantial foundation of deep fractured CBM resources,industry development is constrained and requires continuous exploration of new CBM exploration and development technologies to utilize these resources effectively.展开更多
Recent progress in the physics and engineering design study for themodification programme of JT-60 is presented. In order to achieve a steady state high-βplasmaoperation, which is the dominant issue of this programme...Recent progress in the physics and engineering design study for themodification programme of JT-60 is presented. In order to achieve a steady state high-βplasmaoperation, which is the dominant issue of this programme, physics design for the MHD control and thestability analysis is investigated. Engineering design and the R & D for the superconducting coils,irradiation shield are performed well towards the mission of programme.展开更多
Utilizing energy storage in depleted oil and gas reservoirs can improve productivity while reducing power costs and is one of the best ways to achieve synergistic development of"Carbon Peak–Carbon Neutral"a...Utilizing energy storage in depleted oil and gas reservoirs can improve productivity while reducing power costs and is one of the best ways to achieve synergistic development of"Carbon Peak–Carbon Neutral"and"Underground Resource Utiliza-tion".Starting from the development of Compressed Air Energy Storage(CAES)technology,the site selection of CAES in depleted gas and oil reservoirs,the evolution mechanism of reservoir dynamic sealing,and the high-flow CAES and injection technology are summarized.It focuses on analyzing the characteristics,key equipment,reservoir construction,application scenarios and cost analysis of CAES projects,and sorting out the technical key points and existing difficulties.The devel-opment trend of CAES technology is proposed,and the future development path is scrutinized to provide reference for the research of CAES projects in depleted oil and gas reservoirs.展开更多
The topic was concentrated on environmental technology development in China within the context of China's economic acceleration and reform. Firstly, cleaner technology should be adopted where possible in indu...The topic was concentrated on environmental technology development in China within the context of China's economic acceleration and reform. Firstly, cleaner technology should be adopted where possible in industrial production; secondly, eco agricultural technological system, especially biological technology, should be developed in agricultural production; thirdly, end of pipe solution should focus on waste utilization or recycling technology where appropriate clean technology does not exist; lastly but not the least, existing technologies to minimize eco environmental deterioration such as soil erosion, salinization, desertification and deforestation should also be extended and developed. The mentioned ways of environmental technology development can only be realized on the condition that a resource conservation based production system and life style could be established and appropriate policy secured.展开更多
Using mathematical plasticity theories, universal formability (UF) technology has been developed and applied in the automotive stamping engineering and production. As a formability analysis tool, this technology is th...Using mathematical plasticity theories, universal formability (UF) technology has been developed and applied in the automotive stamping engineering and production. As a formability analysis tool, this technology is the major methodology for the development of stamping expert system (solution provider) for (a) product design and feasibility analysis, (b) material automatic selection using nomograms, (c) draw die design using pre-models, and (d) UF and robustness analysis of die performance in finite element analysis (FEA) environment.展开更多
It is the most available way to obtain self-rooted seedlings by tissue culture,which could breed de-virus seedlings with uniform traits and contribute to improve seedling quality.To construct a complete and efficient ...It is the most available way to obtain self-rooted seedlings by tissue culture,which could breed de-virus seedlings with uniform traits and contribute to improve seedling quality.To construct a complete and efficient technology system,this test used stem with buds of 16 cultivars and super lines including Yali,Jingbaili,03-04-034,03-08-080 and so on as materials to study the best way for explant sampling time and position,sterilization time using HgCl 2 and hormone concentrations.The result indicated that the optimum technology system was that the middle parts of longest shoots before 20 d after full-blossom were sterilized for 8 min by 0.1%HgCl 2 and inoculated on the development medium MS+6-BA 0.5 mg/L+IBA 0.2 mg/L+saccharose 3%+agar 0.6%(pH=5.8),and then trans-inoculated into propagation medium MS+6-BA 1.0 mg/L+IBA 0.3 mg/L+saccharose 3%+agar 0.6%(pH=5.8).展开更多
Environmental technology (ET) refers to the processes and techniques for environmental prevention, reduction, recycling, reuse and rehabilitation. Since 1978, China has launched a series of R&D programs in promoti...Environmental technology (ET) refers to the processes and techniques for environmental prevention, reduction, recycling, reuse and rehabilitation. Since 1978, China has launched a series of R&D programs in promoting environmental science and technology development. Uneven spatial distribution and sectoral structure give us a profile of the present status of ET in China. Both opportunities and constraints are analyzed for the development of ET, and strategies for its future development are presented in this paper.展开更多
Currently, the progress of science and technology has become a key factor in promoting economic development. And the backwardness of science and technology at the grassroots level has undoubtedly restricted the proces...Currently, the progress of science and technology has become a key factor in promoting economic development. And the backwardness of science and technology at the grassroots level has undoubtedly restricted the process of China’s construction of socialist new countryside. Taking socio-economy and the devel- opment of science and technology in Jiaxing as a breakthrough point, and based on the related data of Jiaxing during 1998?2004, this paper analyzes thoroughly the interactive relationship be- tween socio-economy and the development of science and tech- nology. This paper strives to summarize the development track and model of the grassroots work of science and technology so as to provide local governments with references and grounds for drawing up policies for the local work of science and technology.展开更多
China is a large developing country with rapid growth rate. To the year 2050, its electric power will be increased by six to eight times, reaching 1.5—1.8 TW total installed capacity. The development can not only rel...China is a large developing country with rapid growth rate. To the year 2050, its electric power will be increased by six to eight times, reaching 1.5—1.8 TW total installed capacity. The development can not only rely on the existing technology, it is crucial to accelerate the new technology development. This article discusses the perspective of various new technologies from the available energy resources and the required increase of electric power.展开更多
基金supported by National Natural Science Foundation of China“Propagation mechanism and morphology control of fractures created by layer-penetrating fracturing of horizontal wells in roof strata in broken-soft coal seams”(No.:51874349)National Major Science and Technology Project“Development of large-scale oil/gas fields and coalbed methane”(No.:2016ZX05045002-004).
文摘Broken coal structure and low permeability are the main reasons for the difficult production of coalbed methane(CBM)in broken-soft coal seams.In this paper,No.8 coal seam in the Luling Mine of the Huaibei Coal Field was taken as an example to study the way to improve CBM production of broken-soft coal reservoirs.First,drilling,fracturing and production of horizontal wells were considered comprehensively.Then,based on the idea of exploiting CBM through horizontal wells in roof strata close to the broken-soft coal seams,the propagation laws of fractures created by layer-penetrating fracturing of horizontal wells in roof strata were studied,and accordingly the location of horizontal well was optimized.Finally,the CBM horizontal well exploitation technology for the roof strata close to coal seams was developed and tested on site.And the following research results were obtained.First,the vertical fractures created during layer-penetrating fracturing of horizontal wells in roof strata can propagate from the roof strata with high stress values downward to the coal seam with low stress values.In addition,the location of horizontal well has an important influence on the effect of layer-penetrating fracturing.The closer the horizontal well is to the coal seam,the better the fracture propagation effect of layer-penetrating fracturing.Second,the horizontal well should be arranged in the roof strata 1.5 m away from the top of coal seam,so that fracturing stimulation requirements of horizontal wells in roof strata can be satisfied to the uttermost.Third,three key technologies are formed,including the“high-quality,fast and safe”drilling technology,the deep-penetration oriented perforating technology and the“large displacement,large scale,high pad ratio and moderate proppant concentration”active water fracturing technology.Fourth,the gas production with this technology in engineering practice is remarkable.In conclusion,the CBM development technology of horizontal wells in roof strata close to broken-soft coal seams is feasible.The research results provide a new technical method for the development of CBM in broken-soft coal seams.
文摘With the rapid development of e-commerce and big data, online work demand is higher and higher, need to website design is more and more talents. You need to improve students comprehensive practice ability in teaching, let the students not only master knowledge, but also practice, can independently complete a complete project design. This paper takes a certain project as an example, and proposes a project-based task-driven teaching reform method, which can better improve the students comprehensive practical ability, and achieve the purpose of improving the teaching effect.
基金Special Fund for Basic Scientific Research Business Expenses of Central Public Welfare Scientific Research Institutions(S201947)。
文摘This study takes the patent information of China's electric agricultural machinery technology as the research object,and uses patent measurement analysis method and visual analysis tools to carry out statistical analysis and comparative research on the relevant patent information from the perspectives of annual patent applications,patent structure,technological key,main applicants,patent layout,technology lifecycle and so on.The research results show that China's electric agricultural machinery technology innovation is developing rapidly,and the patent categories are mainly utility model and invention patents,and the proportion of invention patents is lower than utility model patents.Universities are the most important innovation subjects in this field,and technology research and development focuses on IPC(international patent classification)subcategories such as A01C(seeding,fertilization),B60K(power,transmission),and A01D(harvesting.mowing).Jiangsu Province and Shandong Province rank the top 2 in the number of domestic patent applications,and the United States and Japan are the two countries with the most layout in China.At present,the growth of electric agricultural machinery technology is weak,but the new technology has strong features,there is no sign of maturity,and it does not have signs of technological aging and still has greater development potential.The results of the study can provide information reference for clarifying the status quo,characteristics and development trend of China's electric agricultural machinery technology innovation.
基金financially supported by the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)(Grant Nos.CUGGC09 and CUG200637)Opening Fund of Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)),Ministry of Education(Grant No.19CX05005A-201)the Sinopec Science and Technology Department(Grant Nos.P2006 and 33550000-21-ZC0611-0006)。
文摘Super-heavy oil is a significant unconventional energy source,and more than 30 years of research have shown that steam-assisted gravity drainage(SAGD)technology is suitable for thick super-heavy oil reservoirs.Recently,more and more thin-layer super-heavy oil reservoirs have been discovered in China,while their deep buried depth and serous heterogeneity make the existing SAGD technology difficult to apply,so it is urgent to improve the existing SAGD technology for the thin-layer super-heavy oil.To this end,this paper focuses on the enlightenment of field application in SAGD technology.Firstly,based on typical SAGD field projects,the development history of SAGD technology in the world was reviewed,and the influence of reservoir physical properties on the application of SAGD technology in thin-layer superheavy oil reservoirs was analyzed.Secondly,the well pattern,wellbore structure,pre-heating,artificial lift,and monitor technique of SAGD were detailed described,and their adjustment direction was expounded for the development of thin-layer super-heavy oil reservoirs.Lastly,the gas-and solventassistant SAGD were comprehensively evaluated,and their application potential in thin-layer superheavy oil reservoirs was studied.The research results can provide theoretical guidance for the application of SAGD technology in thin-layer super-heavy oil reservoirs.
文摘As decarbonization pressure on traditional fossil fuel-related industries gradually intensifies,CCUS has been increasingly incorporated into energy transition strategies by various oil companies.From a development opportunity perspective,oil companies possess four key advantages in developing the CCUS industry:exploration and development technology advantages;geological resource advantages;capital advantages;source-sink matching advantages.In terms of challenges,oil companies face numerous issues in developing the CCUS industry,including technological development,economic viability,and policy and legal aspects.At the national level,China’s oil companies should advocate for improving and optimizing relevant laws and regulations,enhancing the policy support system,incorporating CCUS into the carbon trading market,and strengthening top-level design and medium-to long-term planning;at the enterprise level,they should continuously advance full industrial chain technologies and reduce CCUS project operating costs,selectively participate in industrial segments that suit their capabilities,strengthen CCUS full industrial chain operational capabilities,and enhance talent development and strengthen international exchange and cooperation.
基金Supported by the Canadian International Development Research Center(IDRC)~~
文摘[Objective] This study aimed to provide references for the application of participatory monitoring and evaluation in the development of animal husbandry tech- nology. [Method] With the livelihood improvement program for agricultural and pas- toral area in northern Yunnan as the example, the development process of partici- patory animal husbandry was overviewed. And the monitoring and evaluation pro- cesses of participatory animal husbandry were introduced and analyzed. [Result] The monitoring and evaluation indicator system of participatory animal husbandry technol- ogy included 4 layers, namely technology, institutional system, personnel ability con- struction and effectiveness, and 11 third-level indicators, namely, technical characteristics, superiority-inferiority comparison, community and farmers, technical personnel, project personnel, economic indicators and social indicators. [Conclusion] This study provided the references for the application of participatory monitoring and evaluation in the development of animal husbandry technology.
基金supported by the National Natural Science Foundation of China(52074045,52274074)the Science Fund for Distinguished Young Scholars of Chongqing(CSTB2022NSCQ-JQX0028).
文摘Developing deep fragmented soft coalbed methane(CBM)can significantly enhance domestic natural gas supplies,reduce reliance on imported energy,and bolster national energy security.This manuscript provides a comprehensive review of commonly employed coalbed methane extraction technologies.It then delves into several critical issues in the current stage of CBM exploration and development in China,including the compatibility of existing technologies with CBM reservoirs,the characteristics and occurrence states of CBM reservoirs,critical desorption pressure,and gas generation mechanisms.Our research indicates that current CBM exploration and development technologies in China have reached an internationally advanced level,yet the industry is facing unprecedented challenges.Despite progress in low-permeability,high-value coal seams,significant breakthroughs have not been achieved in exploring other types of coal seams.For different coal reservoirs,integrated extraction technologies have been developed,such as surface pre-depressurisation and segmented hydraulic fracturing of coal seam roof strata.Additionally,techniques like large-scale volume fracturing in horizontal wells have been established,significantly enhancing reservoir stimulation effects and coalbed methane recovery rates.However,all of these technologies are fundamentally based on permeation.These technologies lack direct methods aimed at enhancing the diffusion rate of CBM,thereby failing to fully reflect the unique characteristics of CBM.Current CBM exploration and development theories and technologies are not universally applicable to all coal seams.They do not adequately account for the predominantly adsorbed state of CBM,and the complex and variable gas generation mechanisms further constrain CBM development in China.Finally,continuous exploration of new deep CBM exploration technologies is necessary.Integrating more effective reservoir stimulation technologies is essential to enhance technical adaptability concerning CBM reservoir characteristics,gas occurrence states,and gas generation mechanisms,ultimately achieving efficient CBM development.We conclude that while China possesses a substantial foundation of deep fractured CBM resources,industry development is constrained and requires continuous exploration of new CBM exploration and development technologies to utilize these resources effectively.
文摘Recent progress in the physics and engineering design study for themodification programme of JT-60 is presented. In order to achieve a steady state high-βplasmaoperation, which is the dominant issue of this programme, physics design for the MHD control and thestability analysis is investigated. Engineering design and the R & D for the superconducting coils,irradiation shield are performed well towards the mission of programme.
基金the financial support from the Scientific Research and Technology Development Project of China Energy Engineering Corporation Limited(CEEC-KJZX-04).
文摘Utilizing energy storage in depleted oil and gas reservoirs can improve productivity while reducing power costs and is one of the best ways to achieve synergistic development of"Carbon Peak–Carbon Neutral"and"Underground Resource Utiliza-tion".Starting from the development of Compressed Air Energy Storage(CAES)technology,the site selection of CAES in depleted gas and oil reservoirs,the evolution mechanism of reservoir dynamic sealing,and the high-flow CAES and injection technology are summarized.It focuses on analyzing the characteristics,key equipment,reservoir construction,application scenarios and cost analysis of CAES projects,and sorting out the technical key points and existing difficulties.The devel-opment trend of CAES technology is proposed,and the future development path is scrutinized to provide reference for the research of CAES projects in depleted oil and gas reservoirs.
文摘The topic was concentrated on environmental technology development in China within the context of China's economic acceleration and reform. Firstly, cleaner technology should be adopted where possible in industrial production; secondly, eco agricultural technological system, especially biological technology, should be developed in agricultural production; thirdly, end of pipe solution should focus on waste utilization or recycling technology where appropriate clean technology does not exist; lastly but not the least, existing technologies to minimize eco environmental deterioration such as soil erosion, salinization, desertification and deforestation should also be extended and developed. The mentioned ways of environmental technology development can only be realized on the condition that a resource conservation based production system and life style could be established and appropriate policy secured.
文摘Using mathematical plasticity theories, universal formability (UF) technology has been developed and applied in the automotive stamping engineering and production. As a formability analysis tool, this technology is the major methodology for the development of stamping expert system (solution provider) for (a) product design and feasibility analysis, (b) material automatic selection using nomograms, (c) draw die design using pre-models, and (d) UF and robustness analysis of die performance in finite element analysis (FEA) environment.
基金Supported by Projects from Hebei Natural Science Fund Committee(C2018301032)Hebei Support Project(16226312D-3)Innovation Team Project of Hebei Academy of Agriculture and Forest(C19R0601-2).
文摘It is the most available way to obtain self-rooted seedlings by tissue culture,which could breed de-virus seedlings with uniform traits and contribute to improve seedling quality.To construct a complete and efficient technology system,this test used stem with buds of 16 cultivars and super lines including Yali,Jingbaili,03-04-034,03-08-080 and so on as materials to study the best way for explant sampling time and position,sterilization time using HgCl 2 and hormone concentrations.The result indicated that the optimum technology system was that the middle parts of longest shoots before 20 d after full-blossom were sterilized for 8 min by 0.1%HgCl 2 and inoculated on the development medium MS+6-BA 0.5 mg/L+IBA 0.2 mg/L+saccharose 3%+agar 0.6%(pH=5.8),and then trans-inoculated into propagation medium MS+6-BA 1.0 mg/L+IBA 0.3 mg/L+saccharose 3%+agar 0.6%(pH=5.8).
文摘Environmental technology (ET) refers to the processes and techniques for environmental prevention, reduction, recycling, reuse and rehabilitation. Since 1978, China has launched a series of R&D programs in promoting environmental science and technology development. Uneven spatial distribution and sectoral structure give us a profile of the present status of ET in China. Both opportunities and constraints are analyzed for the development of ET, and strategies for its future development are presented in this paper.
文摘Currently, the progress of science and technology has become a key factor in promoting economic development. And the backwardness of science and technology at the grassroots level has undoubtedly restricted the process of China’s construction of socialist new countryside. Taking socio-economy and the devel- opment of science and technology in Jiaxing as a breakthrough point, and based on the related data of Jiaxing during 1998?2004, this paper analyzes thoroughly the interactive relationship be- tween socio-economy and the development of science and tech- nology. This paper strives to summarize the development track and model of the grassroots work of science and technology so as to provide local governments with references and grounds for drawing up policies for the local work of science and technology.
文摘China is a large developing country with rapid growth rate. To the year 2050, its electric power will be increased by six to eight times, reaching 1.5—1.8 TW total installed capacity. The development can not only rely on the existing technology, it is crucial to accelerate the new technology development. This article discusses the perspective of various new technologies from the available energy resources and the required increase of electric power.
