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Research on Human-Computer Collaboration Paradigm in AIGC-Empowered High-Level Language Programming Courses
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作者 Hongyuan Wang Baokai Zu +2 位作者 Yafang Li Wanting Zhu Hongli Chen 《Journal of Contemporary Educational Research》 2025年第5期285-289,共5页
With the rapid development of artificial intelligence technology,AIGC(Artificial Intelligence-Generated Content)has triggered profound changes in the field of high-level language programming courses.This paper deeply ... With the rapid development of artificial intelligence technology,AIGC(Artificial Intelligence-Generated Content)has triggered profound changes in the field of high-level language programming courses.This paper deeply explored the application principles,advantages,and limitations of AIGC in intelligent code generation,analyzed the new mode of human-computer collaboration in high-level language programming courses driven by AIGC,discussed the impact of human-computer collaboration on programming efficiency and code quality through practical case studies,and looks forward to future development trends.This research aims to provide theoretical and practical guidance for high-level language programming courses and promote innovative development of high-level language programming courses under the human-computer collaboration paradigm. 展开更多
关键词 Human-computer collaboration AIGC high-level language programming Intelligence programming Efficiency improvement
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Pyridine-based ionic sp^(2)carbon-conjugated covalent organic frameworks for selective extraction of Pu(Ⅳ)from high-level liquid waste
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作者 Li-Ying Wang Jun-jie Yu +6 位作者 Shuai Wang Yang Liu Ke-Xian Song Ji-Pan Yu Li-Yong Yuan Zhi-Rong Liu Wei-Qun Shi 《Chinese Chemical Letters》 2025年第8期337-343,共7页
In the current era marked by energy shortages,the advancement of nuclear energy stands as an inevitable progression.The reprocessing of spent nuclear fuel plays a crucial role in determining the sustainability of nucl... In the current era marked by energy shortages,the advancement of nuclear energy stands as an inevitable progression.The reprocessing of spent nuclear fuel plays a crucial role in determining the sustainability of nuclear energy as a viable energy source.Among these processes,the separation and recovery of Pu(Ⅳ)from high-level liquid waste(HLLW)hold paramount significance in terms of safety and strategic implications.Herein,this work focused on the synthesis of two acid-and radiation-resistant pyridine-based sp^(2)c-COFs(COF-IHEP3 and COF-IHEP4),followed by the creation of two pyridine-based ionized sp^(2)c-COFs named COF-IHEP3-CH_(3)NO_(3)and COF-IHEP4-CH3NO3through post-modification.These materials have potential anion exchange capacity for the selective separation of Pu(Ⅳ)in highly acidic conditions.Notably,in 8 mol/L nitric acid solution,COF-IHEP3-CH3NO3demonstrated the capability to eliminate plutonium within 20 min in 98%removal efficiency with a Kdvalue of 2450 m L/g.Experimental and theoretical analysis suggest that the ionized sp^(2)c-COFs exhibit exceptional stability,selectivity,and prevention of secondary contamination towards Pu(Ⅳ)in the presence of multiple ions environments.In short,this work provides an appropriate anion exchange strategy to design ionic sp^(2)c-COFs as a promising platform for Pu(Ⅳ)recovery from HLLW. 展开更多
关键词 Covalentorganic framework Highlyacidic conditions high-level liquidwaste Anion exchange PU(IV)
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Innovative Research on the Development of Higher Education in Heilongjiang Province Serving the“Opening-Up to the North”Strategy
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作者 Zhiyong Fan 《Journal of Contemporary Educational Research》 2025年第10期294-299,共6页
As a pivotal frontier in China’s“Opening-Up to the North”strategy,the supportive and leading role of higher education in Heilongjiang Province is crucial.From a geo-strategic perspective,systematically analyzing th... As a pivotal frontier in China’s“Opening-Up to the North”strategy,the supportive and leading role of higher education in Heilongjiang Province is crucial.From a geo-strategic perspective,systematically analyzing the realistic foundation,core opportunities,and challenges faced by Heilongjiang’s higher education in serving this strategy is a call of the times.Addressing current prominent issues-such as the misalignment between the structure of academic disciplines and strategic needs,insufficient depth in the integration of industry,academia,research,and application,and an underdeveloped ecosystem for international education-requires innovative approaches.These include optimizing the disciplinary cluster system,innovating talent cultivation models,building high-level new think tanks,and creating a resilient international ecosystem.Such measures aim to enhance the support capacity and contribution of higher education to the“Opening-Up to the North”strategy. 展开更多
关键词 opening-up to the North Higher education Disciplinary clusters Geo-strategy Heilongjiang Province
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Adapting High-Level Language Programming(C Language)Education in the Era of Large Language Models
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作者 Baokai Zu Hongyuan Wang +1 位作者 Hongli Chen Yafang Li 《Journal of Contemporary Educational Research》 2025年第5期264-269,共6页
With the widespread application of large language models(LLMs)in natural language processing and code generation,traditional High-Level Language Programming courses are facing unprecedented challenges and opportunitie... With the widespread application of large language models(LLMs)in natural language processing and code generation,traditional High-Level Language Programming courses are facing unprecedented challenges and opportunities.As a core programming language for computer science majors,C language remains irreplaceable due to its foundational nature and engineering adaptability.This paper,based on the rapid development of large model technologies,proposes a systematic reform design for C language teaching,focusing on teaching objectives,content structure,teaching methods,and evaluation systems.The article suggests a teaching framework centered on“human-computer collaborative programming,”integrating prompt training,AI-assisted debugging,and code generation analysis,aiming to enhance students’problem modeling ability,programming expression skills,and AI collaboration literacy. 展开更多
关键词 Large language models(LLMs) high-level language programming C language Human-computer collaborative programming
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Implement the Guiding Principles of the Third Plenary Session of the 20th CPC Central Committee and Ensure High-Quality Development through High-Level Security
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作者 Yang Mingjie Chen Xiangyang +1 位作者 Chen Qinghong Han Yafeng 《Contemporary International Relations》 2025年第1期4-27,共24页
As a major principle underlying the Communist Party of China's(CPC)governance in the new era and a core piece of its holistic approach to national security,ensuring both development and security emphasizes compreh... As a major principle underlying the Communist Party of China's(CPC)governance in the new era and a core piece of its holistic approach to national security,ensuring both development and security emphasizes comprehensive governance from a long-term perspective and influences the world with its global vision.It keeps pace with the times by prioritizing innovative areas and is of great theoretical and practical significance.On the new journey ahead,we must firmly ensure both development and security.More importantly,we must ensure both high-quality development and high-level security,safeguarding the former through the latter.This is an urgent requirement we face in today's world,which has entered a period of turbulence and transformation characterized by increasing complexity.Confronted with the formidable tasks of promoting reform and development while maintaining stability at home and the grave challenges brought about by international turbulence and changes,we must earnestly implement the guiding principles of the 20th CPC National Congress and the third plenary session of the 20th Party Central Committee.We should ensure secure and sustainable development,accelerate efforts to modernize China's national security system and capacity,foster high-level security,and improve the mechanisms for preserving national security in foreign-related affairs.In short,we should strive to achieve a positive interplay between high-quality development and high-level security,so as to effectively safeguard Chinese modernization. 展开更多
关键词 ensure both development and security high-level security new quality combat capabilities third plenary session of the 20th CPC Central Committee
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Effect of Scattered Solar Radiation on the Informativeness of Polarization Lidar Studies of High-Level Clouds
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作者 Ignatii Samokhvalov Ilia Bryukhanov +5 位作者 Ivan Akimov Olesia Kuchinskaia Maxim Penzin Denis Romanov Evgeny Ni Ivan Zhivotenyuk 《Journal of Environmental & Earth Sciences》 2025年第6期148-156,共9页
During daylight laser polarization sensing of high-level clouds(HLCs),the lidar receiving system generates a signal caused by not only backscattered laser radiation,but also scattered solar radiation,the intensity and... During daylight laser polarization sensing of high-level clouds(HLCs),the lidar receiving system generates a signal caused by not only backscattered laser radiation,but also scattered solar radiation,the intensity and polarization of which depends on the Sun’s location.If a cloud contains spatially oriented ice particles,then it becomes anisotropic,that is,the coefficients of directional light scattering of such a cloud depend on the Sun’s zenith and azimuth angles.In this work,the possibility of using the effect of anisotropic scattering of solar radiation on the predictive ability of machine learning algorithms in solving the problem of predicting the HLC backscattering phase matrix(BSPM)was evaluated.The hypothesis that solar radiation scattered on HLCs has no effect on the BSPM elements of such clouds determined with a polarization lidar was tested.The operation of two algorithms for predicting the BSPM elements is evaluated.To train the first one,meteorological data were used as input parameters;for the second algorithm,the azi-muthal and zenith angles of the Sun’s position were added to the meteorological parameters.It is shown that there is no significant improvement in the predictive ability of the algorithm. 展开更多
关键词 high-level Clouds(HLCs) Polarization Lidar Backscattering Phase Matrix(BSPM) Sun’s Azimuthal and Zenith Angles Scattered Solar Radiation Cloud Microphysics Machine Learning(ML) Random Forest
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Estimating shear strength of high-level pillars supported with cemented backfilling using the HoekeBrown strength criterion 被引量:10
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作者 Kaizong Xia Congxin Chen +3 位作者 Xiumin Liu Yue Wang Xuanting Liu Jiahao Yuan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期454-469,共16页
Deep metal mines are often mined using the high-level pillars with subsequent cementation backfilling(HLSCB)mining method.At the design stage,it is therefore important to have a reasonable method for determining the s... Deep metal mines are often mined using the high-level pillars with subsequent cementation backfilling(HLSCB)mining method.At the design stage,it is therefore important to have a reasonable method for determining the shear strength of the high-level pillars(i.e.cohesion and internal friction angle)when they are supported by cemented backfilling.In this study,a formula was derived for the upper limit of the confining pressure σ3max on a high-level pillar supported by cemented backfilling in a deep metal mine.A new method of estimating the shear strength of such pillars was then proposed based on the Hoek eBrown failure criterion.Our analysis indicates that the horizontal stress σhh acting on the cemented backfill pillar can be simplified by expressing it as a constant value.A reasonable and effective value for σ3max can then be determined.The value of s3max predicted using the proposed method is generally less than 3 MPa.Within this range,the shear strength of the high-level pillar is accurately calculated using the equivalent MohreCoulomb theory.The proposed method can effectively avoid the calculation of inaccurate shear strength values for the high-level pillars when the original HoekeBrown criterion is used in the presence of large confining pressures,i.e.the situation in which the cohesion value is too large and the friction angle is too small can effectively be avoided.The proposed method is applied to a deep metal mine in China that is being excavated using the HLSCB method.The shear strength parameters of the high-level pillars obtained using the proposed method were input in the numerical simulations.The numerical results show that the recommended level heights and sizes of the high-level pillars and rooms in the mine are rational. 展开更多
关键词 Deep metal mines high-level pillars HoekeBrown strength criterion Cemented backfilling Confining pressure Shear strength
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Research on the Path of Cultivating High-Level Technical and Skilled Talents in Vocational Undergraduate Colleges and Universities
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作者 Kan Su Seong Pek Lim Linli Yao 《Journal of Contemporary Educational Research》 2024年第7期150-157,共8页
This paper explores strategies to cultivate high-level technical talents in vocational undergraduate colleges by analyzing their development,the essence of such talents,and proposing several key measures.Strategies in... This paper explores strategies to cultivate high-level technical talents in vocational undergraduate colleges by analyzing their development,the essence of such talents,and proposing several key measures.Strategies include optimizing professional settings and curricula,enhancing school-enterprise cooperation and the integration of industry-university-research,improving teaching staff quality and educational standards,and expanding international cooperation.The importance of policy support and funding and establishing robust quality assurance systems is emphasized for effectively cultivating skilled talents in vocational undergraduate colleges. 展开更多
关键词 Vocational undergraduate colleges high-level technical talents Professional setting Innovation and entrepreneurship education
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Iron deficiency, supplementation, and sports performance in female athletes: A systematic review
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作者 Michael Pengelly Kate Pumpa +1 位作者 David Bruce Pyne Naroa Etxebarria 《Journal of Sport and Health Science》 2025年第3期83-95,共13页
Background:Iron facilitates key biological functions underpinning sports performance,and up to 60%of female athletes experience iron deficiency.However,the effects of iron deficiency on sports performance in female at... Background:Iron facilitates key biological functions underpinning sports performance,and up to 60%of female athletes experience iron deficiency.However,the effects of iron deficiency on sports performance in female athletes is unclear,as are the degree of benefits of iron supplementation(FeSup).This study characterizes the effects of iron deficiency and FeSup on sports performance in high-level female athletes.Methods:Searches of the electronic databases MEDLINE,SPORTDiscus,Web of Science,Scopus,and CINAHL were performed in July 2023.Studies were included that evaluated the effects of iron deficiency or FeSup on sports performance in high-level(maximal oxygen uptake(VO2max)>45 mL/kg/min,or trained>5 h/week)iron deficient(ID)(serum ferritin(sFer)<40 mg/L)female athletes.Studies were assessed using a modified Downs and Black Quality Assessment Checklist.Results:A total of 23 studies comprising 669 athletes(age range:13-47 years)across 16 sports were included in the review.Iron deficiency negatively affects endurance performance by 3%-4%.However,endurance performance improved by 2%-20%when ID athletes were treated with 100 mg/day of elemental iron for up to 56 days via oral supplementation,or bi-daily via parenteral administration over 8-10 days.ID nonanemic athletes with low sFer stores may be predisposed to reduced maximal aerobic capacity.However,maximal aerobic capacity improved by 6%-15%following 16 mg/day-100 mg/day of elemental iron for 36-126 days.Isokinetic strength and anaerobic power performance may be impeded(-23%to+4%)among ID athletes,but the effect of FeSup on anaerobic power varied markedly(-5%to+9%)following 100 mg/day of elemental iron over 42-56 days,or 100 mg of elemental iron bi-daily over 8-10 days.The quality of studies was moderate(77%),ranging from low(57%)to high(100%).Moststudies(n=18)contained group sizes-20 athletes,thus limiting the likelihood of detecting significant effects(statistical power>0.80).Conclusion:High-level ID female athletes experience a negative impact on endurance performance,which can be improved by supplementing with»100 mg of elemental iron per day or bi-daily.The decrements in other performance parameters characterizing a range of sports coincide with the severity of iron deficiency. 展开更多
关键词 ANEMIA Non-anemia Mineral deficiency WOMAN high-level athletes
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Gas breakthrough in compacted Gaomiaozi bentonite under rigid boundary conditions
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作者 Weimin Ye Sai Li +2 位作者 Puhuai Lu Qiong Wang Yonggui Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第6期3883-3893,共11页
Predicting the gas breakthrough pressure of saturated compacted bentonite is crucial for ensuring the long-term safe operation of deep geological repositories for the disposal of high-level radioactive nuclear wastes.... Predicting the gas breakthrough pressure of saturated compacted bentonite is crucial for ensuring the long-term safe operation of deep geological repositories for the disposal of high-level radioactive nuclear wastes.In this work,the swelling pressure,water injection,gas injection and mercury intrusion porosimetry(MIP)tests on saturated compacted Gaomiaozi(GMZ)bentonite specimens with a dry density of 1.3 Mg/m^(3),1.4 Mg/m^(3),1.5 Mg/m^(3),1.6 Mg/m^(3) and 1.7 Mg/m^(3) were conducted.Subsequently,the relationships between the swelling pressure and average inter-particle distance,as well as between the gas entry pressure and the maximum effective pore size were analyzed and established.Considering that gas migration and breakthrough are all closely related to the pore structures of the tested geomaterials,a novel gas breakthrough pressure prediction model based on the pore size distribution(PSD)curve was constructed using an existing prediction model based on gas entry pressure and swelling pressure.Finally,based on the test results of the specimens 1.5 Mg/m^(3),1.6 Mg/m^(3) and 1.7 Mg/m^(3),gas breakthrough pressures of the specimens with dry densities of 1.3 Mg/m^(3) and 1.4 Mg/m^(3) were predicted.The results show that the calculated gas breakthrough pressures of 0.76 MPa and 1.28 MPa are very close to the measured values of 0.80 MPa and 1.30 MPa,validating the accuracy of the proposed model. 展开更多
关键词 high-level nuclear waste disposal Compacted bentonite Gas breakthrough pressure Pore size distribution Model
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The Unique “Visible Hand” and China’s Economic Development——From the Perspective of Systematic Thinking in Economic Development
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作者 CUI Shaozhong 《Chinese Business Review》 2025年第1期1-8,共8页
The history and practice of the great rejuvenation of the Chinese nation show that the founding of the Communist Party of China(CPC)has opened up a new era in the Chinese history and the CPC constitutes the fundamenta... The history and practice of the great rejuvenation of the Chinese nation show that the founding of the Communist Party of China(CPC)has opened up a new era in the Chinese history and the CPC constitutes the fundamental leadership and organizational guarantee for the realization of the great rejuvenation of the Chinese nation.The CPC has united and led the Chinese people in having founded the People’s Republic of China(PRC),in having established the basic socialist system,in having eliminated all exploitation systems,and in having laid the fundamental political premise and institutional foundation for the great rejuvenation of the Chinese nation.The CPC has also led the Chinese people in having carried out Reform and Opening-up,in having launched the road of socialism with Chinese characteristics,and in having realized the great leap of the Chinese nation from standing up to becoming rich.Since its 18th National Congress,standing at the historical starting point of the new era,the CPC has led the people in unremitting struggle,has opened up a new realm of socialism with Chinese characteristics in the new era,and has achieved a historical breakthrough for the Chinese nation from becoming rich to becoming strong.The course of the CPC leading the Chinese people to realize the great rejuvenation of the Chinese nation reflects the systematic thinking of economic development and the integrated utilization of Marxist theory of economic development and traditional theories of economic development.The history of the CPC uniting and leading the people to strive for the great rejuvenation of the Chinese nation enlightens us that the CPC,as the“visible hand”of the cause of socialism with Chinese characteristics,is the fundamental guarantee for the great rejuvenation of the Chinese nation,and China must adhere to the CPC’s leadership. 展开更多
关键词 CPC the great rejuvenation the basic system of socialism Reform and opening-up socialism with Chinese characteristics
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High-level radioactive waste disposal in China: update 2010 被引量:44
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作者 Ju Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2010年第1期1-11,共11页
For geological disposal of high-level radioactive waste (HLW), the Chinese policy is that the spent nuclear fuel (SNF) should be reprocessed first, followed by vitrification and final disposal. The preliminary rep... For geological disposal of high-level radioactive waste (HLW), the Chinese policy is that the spent nuclear fuel (SNF) should be reprocessed first, followed by vitrification and final disposal. The preliminary repository concept is a shaft-tunnel model, located in saturated zones in granite, while the final waste form for disposal is vitrified high-level radioactive waste. In 2006, the government published a long-term research and development (R&D) plan for geological disposal of high-level radioactive waste. The program consists of three steps: (1) laboratory studies and site selection for a HLW repository (2006-2020); (2) underground in-situ tests (2021-2040); and (3) repository construction (2041-2050) followed by operation. With the support of China Atomic Energy Authority, comprehensive studies are underway and some progresses are made. The site characterization, including deep borehole drilling, has been performed at the most potential Beishan site in Gansu Province, Northwestern China. The data from geological and hydrogeological investigations, in-situ stress and permeability measurements of rock mass are presented in this paper. Engineered barrier studies are concentrated on the Gaomiaozi bentonite. A mock-up facility, which is used to study the thermo-hydro-mechano-chemical (THMC) properties of the bentonite, is under construction. Several projects on mechanical properties of Beishan granite are also underway. The key scientific challenges faced with HLW disposal are also discussed. 展开更多
关键词 geological disposal high-level radioactive waste R&D program site selection BENTONITE
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The Beishan underground research laboratory for geological disposal of high-level radioactive waste in China:Planning, site selection,site characterization and in situ tests 被引量:93
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作者 Ju Wang Liang Chen +1 位作者 Rui Su Xingguang Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 CSCD 2018年第3期411-435,共25页
With the rapid development of nuclear power in China, the disposal of high-level radioactive waste(HLW) has become an important issue for nuclear safety and environmental protection. Deep geological disposal is inte... With the rapid development of nuclear power in China, the disposal of high-level radioactive waste(HLW) has become an important issue for nuclear safety and environmental protection. Deep geological disposal is internationally accepted as a feasible and safe way to dispose of HLW, and underground research laboratories(URLs) play an important and multi-faceted role in the development of HLW repositories. This paper introduces the overall planning and the latest progress for China's URL. On the basis of the proposed strategy to build an area-specific URL in combination with a comprehensive evaluation of the site selection results obtained during the last 33 years, the Xinchang site in the Beishan area,located in Gansu Province of northwestern China, has been selected as the final site for China's first URL built in granite. In the process of characterizing the Xinchang URL site, a series of investigations,including borehole drilling,geological mapping, geophysical surveying,hydraulic testing and in situ stress measurements, has been conducted. The investigation results indicate that the geological,hydrogeological, engineering geological and geochemical conditions of the Xinchang site are very suitable for URL construction. Meanwhile, to validate and develop construction technologies for the Beishan URL, the Beishan exploration tunnel(BET), which is a 50-m-deep facility in the Jiujing sub-area, has been constructed and several in situ tests, such as drill-and-blast tests, characterization of the excavation damaged zone(EDZ), and long-term deformation monitoring of surrounding rocks, have been performed in the BET. The methodologies and technologies established in the BET will serve for URL construction.According to the achievements of the characterization of the URL site, a preliminary design of the URL with a maximum depth of 560 m is proposed and necessary in situ tests in the URL are planned. 展开更多
关键词 Beishan Xinchang site GRANITE Underground research laboratory(URL) high-level radioactive waste(HLW) Geological disposal
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Migration of Some Elements and Radionuclides across aGranite-Granite Contact Zone: A Natural Analoguefor Safe Disposal of High-Level Radwastes 被引量:4
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作者 LUO Xingzhang MIN Maozhong +4 位作者 ZHANG Guanghui LI Xianguo YANG Zhe ZHAI Liying Zhu Deling 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第4期418-428,共11页
Abstract Elements and natural radionuclides in the contact zone of two granites with different ages would migrate from one to the other because of the difference in their chemical contents and later water-rock interac... Abstract Elements and natural radionuclides in the contact zone of two granites with different ages would migrate from one to the other because of the difference in their chemical contents and later water-rock interactions. This migration could serve as an analogue for the near-field process of radwastes in a high-level radwaste deep geological disposal repository. 展开更多
关键词 high-level radwaste safe disposal granitic contact zone natural analogue
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Three-dimensional numerical simulation of methane drainage by high-level drill holes in a lower protective coal seam with a “U” type face 被引量:8
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作者 Xingkui Liu Shuzhao Yang 《International Journal of Coal Science & Technology》 EI CAS 2014年第4期434-440,共7页
Different drill-hole positions may produce different drainage results in low protective coal seams.To investigate this possibility,a 3D stope model is established,which covers three kinds of drill holes.The FLUENT com... Different drill-hole positions may produce different drainage results in low protective coal seams.To investigate this possibility,a 3D stope model is established,which covers three kinds of drill holes.The FLUENT computational fluid mechanics software is used to solve the mass,momentum and species conservation equations of the model.The spatial distributions of oxygen and methane was obtained by calculations and the drainage results of different drill-hole positions were compared.The results show that,from top to bottom,methane dilution by oxygen weakens gradually from the intake to the return side,and methane tends to float;methane and oxygen distribute horizontally.The high-level crossing holes contribute to better methane drainage and a greater level of control.Around these holes,the methane density decreases dramatically and a "half circle"distribution is formed.The methane density decreases on the whole,but a proportion of the methane moves back to deep into the goaf.The research findings provide theoretical grounds for methane drainage. 展开更多
关键词 Low protective coal seam 3D stope model high-level drill Drainage effects
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High-level soluble expression of the hemA gene from Rhodobacter capsulatus and comparative study of its enzymatic properties 被引量:4
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作者 Jia-wei LOU Li ZHU +3 位作者 Mian-bin WU Li-rong YANG Jian-ping LIN Pei-lin CEN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2014年第5期491-499,共9页
The Rhodobacter capsulatus hemA gene, which encodes 5-aminolevulinic acid synthase (ALAS), was expressed in Escherichia coil Rosetta (DE3) and the enzymatic properties of the purified recombinant ALAS (RC-ALAS) ... The Rhodobacter capsulatus hemA gene, which encodes 5-aminolevulinic acid synthase (ALAS), was expressed in Escherichia coil Rosetta (DE3) and the enzymatic properties of the purified recombinant ALAS (RC-ALAS) were studied. Compared with ALASs encoded by hemA genes from Agrobacterium radiobacter(AR-ALAS) and Rhodobacter sphaeroides (RS-ALAS), the specific activity of RC-ALAS reached 198.2 U/mg, which was about 31.2% and 69.5% higher than those of AR-ALAS (151.1 U/mg) and RS-ALAS (116.9 U/mg), respectively. The optimum pH values and temperatures of the three above mentioned enzymes were all pH 7.5 and 37 ℃, respectively. Moreover, RC-ALAS was more sensitive to pH, while the other two were sensitive to temperature. The effects of metals, ethylene diamine tetraacetic acid (EDTA), and sodium dodecyl sulfate (SDS) on the three ALASs were also investigated. The results indicate that they had the same effects on the activities of the three ALASs. SDS and metal ions such as Co^2+, Zn^2+, and Cu^2+ strongly inhibited the activities of the ALASs, while Mn^2+ exerted slight inhibition, and K^+, Ca^2+, Ba^2+, Mg^2+, or EDTA had no significant effect. The specificity constant of succinyl coenzyme A [(kcatlKm)^S-CoA] of RC-ALAS was 1.4989, which was higher than those of AR-ALAS (0.7456) and RS-ALAS (1.1699), showing its high catalytic efficiency. The fed-batch fermentation was conducted using the recombinant strain containing the R. capsulatus hemA gene, and the yield of 5-aminolevulinic acid (ALA) achieved was 8.8 g/L (67 mmol/L) under the appropriate conditions. 展开更多
关键词 5-Aminolevulinic acid Rhodobacter capsulatus high-level expression Enzymatic properties
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Patterns and Experience of China's Four Decades of Opening-Up 被引量:3
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作者 Yang Danhui 《China Economist》 2018年第4期68-95,共28页
China's four decades of opening-up coincided with the trend of the world economy, and contributed to its own economic development. With a gradualist approach, China achieved opening-up without causing economic and so... China's four decades of opening-up coincided with the trend of the world economy, and contributed to its own economic development. With a gradualist approach, China achieved opening-up without causing economic and social repercussions, and unleashed institutional dividends that facilitated its reform and development. This approach has breathed lasting momentum and vitality into China's economic growth and structural transition, and improved China's industrial competitiveness and status in the international division of labor. As a basic national strategy and one of the country's five development concepts, opening-up is essential for China to pursue peaceful development and stand proudly in the family of nations. Facing new changes in domestic and international environments in the new era, particularly increasing competition among major countries such as China and the United States, China should proactively explore a new model of opening-up, refocus opening-up from policy supply to capacity building, and form a new pattern of opening-up on all fronts for high-quality economic development. 展开更多
关键词 opening-up institutional innovation major-country competition new patternof comprehensive opening-up
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Controlling mine pressure by subjecting high-level hard rock strata to ground fracturing 被引量:4
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作者 Rui Gao Tiejun Kuang +2 位作者 Yanqun Zhang Wenyang Zhang Chunyang Quan 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第6期1336-1350,共15页
When mining extra-thick coal seams,the main cause of strong ground pressure are the high-level thick and hard strata,but as yet there is no active and effective control technology.This paper proposes the method of sub... When mining extra-thick coal seams,the main cause of strong ground pressure are the high-level thick and hard strata,but as yet there is no active and effective control technology.This paper proposes the method of subjecting hard roofs to ground fracturing,and physical simulation is used to study the control effect of ground fracturing on the strata structure and energy release.The results show that ground fracturing changes the structural characteristics of the strata and reduces the energy release intensity and the spatial extent of overburden movement,thereby exerting significant control on the ground pressure.The Datong mining area in China is selected as the engineering background.An engineering test was conducted on site by ground horizontal well fracturing,and a 20-m-thick hard rock layer located 110 m vertically above the coal seam was targeted as the fracturing layer.On-site microseismic monitoring shows that the crack propagation length is up to 216 m and the height is up to 50 m.On-site mine pressure monitoring shows that(1)the roadway deformation is reduced to 100 mm,(2)the periodic weighting characteristics of the hydraulic supports are not obvious,and(3)the ground pressure in the working face is controlled significantly,thereby showing that the ground fracturing is successful.Ground fracturing changed the breaking characteristics of the high-level hard strata,thereby helping to ameliorate the stress concentration in the stope and providing an effective control approach for hard rock. 展开更多
关键词 Ground fracturing high-level hard roof Breakage characteristics Pressure control Safety mining
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High-level expression and purification of Plutella xylostella acetylcholinesterase in Pichia pastoris and its potential application 被引量:2
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作者 LIU Niu CHE Jun +2 位作者 LAI Duo WEN Jin-jun XU Han-hong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第6期1358-1366,共9页
The acetylcholinesterase 2(AChE2)cloned from Plutella xylostella was first successfully expressed in methylotrophic yeast Pichia pastoris GS115.One transformant with high-level expression of the recombinant AChE(rA... The acetylcholinesterase 2(AChE2)cloned from Plutella xylostella was first successfully expressed in methylotrophic yeast Pichia pastoris GS115.One transformant with high-level expression of the recombinant AChE(rAChE,23.2 U mL-1in supernatant)was selected by plating on increasing concentrations of antibiotic G418 and by using a simple and specific chromogenic reaction with indoxyl acetate as a substrate.The maximum production of r ACh E reached about 11.8 mg of the enzyme protein per liter of culture.The r ACh E was first precipitated with ammonium sulfate(50%saturation)and then purified with procainamide affinity column chromatography.The enzyme was purified 12.1-fold with a yield of 22.8%and a high specific activity of 448.3 U mg-1.It was sensitive to inhibition by methamidophos and pirimicarb,the calculated 50% inhibitory concentration(IC50)values of the two pesticides were 0.357 and 0.888 mg L-1,respectively,and the calculated 70% inhibitory concentration(IC70)values were 0.521 and 0.839 mg L-1,respectively.The results suggested that it has a potential application in the detection of pesticide residues. 展开更多
关键词 Plutella xylostella ACETYLCHOLINESTERASE Pichia pastoris high-level expression
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High-level disinfection of gastrointestinal endoscope reprocessing 被引量:15
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作者 King-Wah Chiu Lung-Sheng Lu Shue-Shian Chiou 《World Journal of Experimental Medicine》 2015年第1期33-35,共3页
High level disinfection(HLD) of the gastrointestinal(GI)endoscope is not simply a slogan, but rather is a form of experimental monitoring-based medicine. By definition,GI endoscopy is a semicritical medical device. He... High level disinfection(HLD) of the gastrointestinal(GI)endoscope is not simply a slogan, but rather is a form of experimental monitoring-based medicine. By definition,GI endoscopy is a semicritical medical device. Hence,such medical devices require major quality assurance for disinfection. And because many of these items are temperature sensitive, low-temperature chemical methods, such as liquid chemical germicide, must be used rather than steam sterilization. In summarizing guidelines for infection prevention and control for GI endoscopy, there are three important steps that must be highlighted: manual washing, HLD with automated endoscope reprocessor, and drying. Strict adherence to current guidelines is required because compared to any other medical device, the GI endoscope is associated with more outbreaks linked to inadequate cleaning or disinfecting during HLD. Both experimental evaluation on the surveillance bacterial cultures and in-use clinical results have shown that, the monitoring of the stringent processes to prevent and control infection is an essential component of the broader strategy to ensure the delivery of safe endoscopy services, because endoscope reprocessing is a multistep procedure involving numerous factors that can interfere with its efficacy. Based on our years of experience in the surveillance of culture monitoring of endoscopic reprocessing, we aim in this study to carefully describe what details require attention in the GI endoscopy disinfection and to share our experience so that patients can be provided with high quality and safe medical practices. Quality management encompasses all aspects of pre- and postprocedural care including the efficiency of the endoscopy unit and reprocessing area, as well as the endoscopic procedure itself. 展开更多
关键词 Automated endoscope reprocessor Bacterial culture Gastrointestinal endoscopy high-level disinfection Liquid chemical germicide
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