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Exploring the Long-Term Mechanism of the Construction of College Teachers’Ethics in the New Era Under the Concept of“Sanquan Education”
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作者 Jing Zuo Xiaoyue Liu 《Journal of Contemporary Educational Research》 2024年第1期140-146,共7页
This paper takes the long-term mechanism exploration of the construction of teachers’ethics in the new era under the concept of“Sanquan education,”aiming to explore how to establish a long-term mechanism of the con... This paper takes the long-term mechanism exploration of the construction of teachers’ethics in the new era under the concept of“Sanquan education,”aiming to explore how to establish a long-term mechanism of the construction to meet the needs of college education development under the background of the new era.A series of targeted measures and suggestions are put forward,including improving the system and mechanism,strengthening the education and training of teachers’ethics,and establishing the evaluation and assessment mechanism.The implementation of these measures can promote the formation of the long-term mechanism of the construction of teachers’ethics in colleges and universities,improve teachers’ethics and behavior quality,and provide strong support for the development of education in colleges and universities. 展开更多
关键词 Sanquan education ETHICS College education long-term mechanism Teacher quality
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Countermeasures for Establishing a Long-term Security Mechanism for Landless Farmers
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作者 Jiefang ZHU 《Asian Agricultural Research》 2020年第1期25-27,31,共4页
In the process of urbanization,farmers will inevitably lose their land,which is resulted from the large-scale requisition of rural collective land.The imperfect social security system in rural areas has resulted in a ... In the process of urbanization,farmers will inevitably lose their land,which is resulted from the large-scale requisition of rural collective land.The imperfect social security system in rural areas has resulted in a large number of landless farmers being transformed into urban poor people.Therefore,proper resettlement of landless farmers and the establishment of a long-term security mechanism for ensuring the basic livelihood of landless farmers are important issues that need to be resolved in the process of China’s social and economic development. 展开更多
关键词 Landless FARMERS long-term SECURITY mechanism COUNTERMEASURES
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Evolution of Microstructure and Mechanical Property during Long-Term Aging in Udimet 720Li 被引量:6
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作者 Lanzhang ZHOU and Valentino LUPINC CNR-TeMPE, Via R. Cozzi 53, 20125 Milano, Italy Jianting GUO Institute of Metal Research, CAS, 72 Wenhua Road, Shenyang 110016, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第6期633-637,共5页
Thermal stabilities of microstructure and mechanical property have been investigated on superalloy U720Li, which is of great interest of application for jet engine and land-based turbine disc. The results showed that,... Thermal stabilities of microstructure and mechanical property have been investigated on superalloy U720Li, which is of great interest of application for jet engine and land-based turbine disc. The results showed that, the primary and secondary gamma' particles maintain good thermal stability at 650 and 700 degreesC with aging time up to 3000 h, while the tertiary gamma' is apparently dependent on aging temperature and time. The tertiary gamma' particles undergo a procedure of coarsening, dissolution and eventually complete disappearance with the increasing of aging time and temperature. They exhibit unusual high sensibility upon aging temperature, which is attributed to the lattice misfit between the gamma' precipitates and the matrix in the alloy. The grain boundary phase M23C6 remains stable without forming of sigma phase even with aging time up to 3000 h at 700 degreesC. Microhardness decreases apparently with increasing aging time and aging temperature. Theoretical analysis based on dislocation mechanism indicates that the change of microhardness should be attributed to the evolution of the tertiary gamma' during aging. 展开更多
关键词 Evolution of Microstructure and mechanical Property during long-term Aging in Udimet 720Li LONG
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Comprehensive analyses of initiation and failure mechanisms of the 2017 Xinmo catastrophic rockslide 被引量:1
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作者 ZHOU Jia-wen FAN Gang +1 位作者 CHEN Qin YANG Xing-guo 《Journal of Mountain Science》 SCIE CSCD 2022年第6期1525-1540,共16页
The failure of the 2017 Xinmo catastrophic rockslide in Maoxian County, Sichuan, Southwest China was a combined effect of long-term and shortterm triggering factors. Field investigation, historical data collection, la... The failure of the 2017 Xinmo catastrophic rockslide in Maoxian County, Sichuan, Southwest China was a combined effect of long-term and shortterm triggering factors. Field investigation, historical data collection, laboratory tests, chemical and microstructure analysis and numerical simulations were adopted herein to reveal the initiation and failure mechanism of the Xinmo rockslide. The analytical results showed that this failure involved the coupling of several triggering factors. The initial cracks in the rock mass were induced by historical earthquakes due to the convex topography and the direction effect. Rock masses from the source area of the Xinmo rockslide contain water-sensitive minerals, i.e., albite and chamosite, and the easily oxidized chemical element Fe, resulting in obvious strength deterioration under the action of water. The scanning electron microscopy(SEM) experimental results indicated that the internal structure of the rock mass is conducive to weathering. The compressive and shear strengths of the rock mass were reduced due to freeze-thaw cycles and weathering. The antecedent rainfall further deteriorated the stability of the slope, and stress and deformation accumulated continually in the locked section. Finally, the locked section sheared out, and the slope failed. An entrainment effect was observed in the Xinmo rockslide due to the presence of old landslide deposits and the antecedent rainfall, resulting in an amplification of the catastrophic rockslide. A simplified three dimensional analysis model was established in this study to reveal the influence of the triggering factors on the failure mechanism of the Xinmo rockslide. 展开更多
关键词 Xinmo Rockslide LANDSLIDE Failure mechanism long-term evolution RAINFALL Entrainment effect
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A Hybrid Handover Forecasting Mechanism Based on Fuzzy Forecasting Model in Cellular Networks 被引量:1
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作者 Hua Qu Yanpeng Zhang +2 位作者 Jihong Zhao Gongye Ren Weipeng Wang 《China Communications》 SCIE CSCD 2018年第6期84-97,共14页
As the increasing demand for mobile communications and the shrinking of the coverage of cells, handover mechanism will play an important role in future wireless networks to provide users with seamless mobile communica... As the increasing demand for mobile communications and the shrinking of the coverage of cells, handover mechanism will play an important role in future wireless networks to provide users with seamless mobile communication services. In order to guarantee the user experience, the handover decision should be made timely and reasonably. To achieve this goal, this paper presents a hybrid handover forecasting mechanism, which contains long-term and short-term forecasting models. The proposed mechanism could cooperate with the standard mechanisms, and improve the performance of standard handover decision mechanisms. Since most of the parameters involved are imprecise, fuzzy forecasting model is applied for dealing with predictions of them. The numerical results indicate that the mechanism could significantly decrease the rate of ping-pong handover and the rate of handover failure. 展开更多
关键词 handover forecasting mechanism fuzzy forecasting model long-term forecasting model short-term forecasting model
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Research and Practice of Long- term Mechanism of Highlighting the Local Industry Characteristics of the Garden Engineering and Technical Expertise Internship
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作者 ZHOU Yiping 《International English Education Research》 2017年第6期97-100,共4页
The higher vocational education has the dual attributes of higher education and vocational education, with vocational education development pace continues to accelerate, the establishment of vocational schools and sch... The higher vocational education has the dual attributes of higher education and vocational education, with vocational education development pace continues to accelerate, the establishment of vocational schools and school-enterprise cooperation corporate long-term mechanism must be addressed now become a good core issues as soon as possible, to achieve effective implementation of internships, we must achieve five-win of social, school, business, students and parents, to a certain extent, for the regional industry economic development. 展开更多
关键词 Landscape Engineering Technics School-Enterprise Cooperation Internships long-term mechanism
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Could Long-Term Stability Last Forever?
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作者 Maria K. Koleva 《Journal of Modern Physics》 CAS 2023年第4期450-460,共11页
The subject of the present paper is to prove that the recently introduced conjecture of boundedness puts a ban over the view of stability as asymptotic property. This result comes in sharp contrast with the prescripti... The subject of the present paper is to prove that the recently introduced conjecture of boundedness puts a ban over the view of stability as asymptotic property. This result comes in sharp contrast with the prescription of the traditional thermodynamics and statistical physics which consider the existence of equilibrium as asymptotic property of all systems. The difference commences from the use of infinitesimal calculus as the basic implement for modelling by the latter while the primary premise of the conjecture of boundedness is sustaining the energy/matter/information permanently bounded and finite. The latter property overrules the infinitesimal calculus as the major implement of modelling because, among all, it is proven that the traditional one suffers unsoluble difficulties. 展开更多
关键词 long-term Stability Equilibrium Infinitesimal Calculus BOUNDEDNESS Decomposition Theorem Certain Information Universal mechanism for Collapse
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MICROSTRUCTURE AND MECHANICAL PROPERTIES OF Fe-Ni-Co-BASE SUPERALLOY AFTER LONGTERM AGING AT 650℃ 被引量:2
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作者 WANG Shuhe GUO Jianting LAI Wanhui GE Yunlong TAN Minghui LI Hui Institute of Metal Research,Academia Sinica,Shenyang,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1991年第3期194-198,共5页
The microstructure and mechanical properties of a Ni-Fe-Co base superalloy with low thermal expansion coefficient after aging at 650℃ for 200,500,1000 and 2000 h have been investigated.It was found that they are stab... The microstructure and mechanical properties of a Ni-Fe-Co base superalloy with low thermal expansion coefficient after aging at 650℃ for 200,500,1000 and 2000 h have been investigated.It was found that they are stable at 650℃.This alloy is believed to.fill the re- quirements for long time service to aircraft engine. 展开更多
关键词 SUPERALLOY MICROSTRUCTURE mechanical property long-term aging
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Design,construction and mechanical behavior of relics of complete large Longyou rock caverns carved in argillaceous siltstone ground 被引量:3
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作者 Zhifa Yang1, Zhongqi Yue2, Lihui Li1 1 Key Laboratory of Engineering Geomechanics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China 2 Department of Civil Engineering, the University of Hong Kong, Hong Kong, China 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2011年第2期131-152,共22页
This paper presents a comprehensive summary of data, analyses and findings from the investigations over the past twelve years about the relics of large Longyou rock caverns carved about 2 000 years ago at shallow dept... This paper presents a comprehensive summary of data, analyses and findings from the investigations over the past twelve years about the relics of large Longyou rock caverns carved about 2 000 years ago at shallow depths in argillaceous siltstone. The paper presents the typical features associated with the rock caverns. They include structures, large spans, portals, extreme shallow-buried depths, imprints, drainages, inclined ceiling, inclined sidewalls, slender rock pillars, rock staircases, site and strata selections, caving lighting, carving method, and underground construction surveying. They are used to reconstruct and highlight the design and construction methods adopted by the ancients. The paper further demonstrates that the relics of the complete large rock caverns are a consequence of coincidental combinations of ancient human effort and natural factors. The full occupation of water with weak acidity in the large rock caverns with the soft surrounding rocks of weak alkalinity is found to be the main factor ensuring and preserving the caverns to have been stable and integral over 2 000 years. However, the five unwatered complete rock cavern relics have been experiencing various deteriorations and small failures including cracks, seepage, small rock falls and delaminating ceiling rocks. Although these deteriorations have been repaired and stabilized effectively, the paper demonstrates that an entire roof collapse failure is highly possible in the near future to each of the five unwatered rock cavern relics. The findings presented in this paper are also invaluable both to the long-term protection and preservation of the large rock cavern relics of national and international interests and importance, and to extend and enrich our experience and knowledge on the long-term stability and integrity of man-made underground rock cavern engineering projects. 展开更多
关键词 rock cavern rock mechanics rock engineering long-term stability and integrity argillaceous siltstone environment
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Long-term stability analysis of large-scale underground plant of Xiangjiaba hydro-power station 被引量:2
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作者 徐卫亚 聂卫平 +3 位作者 周先齐 石崇 王伟 冯树荣 《Journal of Central South University》 SCIE EI CAS 2011年第2期511-520,共10页
Numerical analysis of the optimal supporting time and long-term stability index of the surrounding rocks in the underground plant of Xiangjiaba hydro-power station was carried out based on the rheological theory. Firs... Numerical analysis of the optimal supporting time and long-term stability index of the surrounding rocks in the underground plant of Xiangjiaba hydro-power station was carried out based on the rheological theory. Firstly,the mechanical parameters of each rock group were identified from the experimental data; secondly,the rheological calculation and analysis for the cavern in stepped excavation without supporting were made; finally,the optimal time for supporting at the characteristic point in a typical section was obtained while the creep rate and displacement after each excavation step has satisfied the criterion of the optimal supporting time. Excavation was repeated when the optimal time for supporting was identified,and the long-term stability creep time and the maximum creep deformation of the characteristic point were determined in accordance with the criterion of long-term stability index. It is shown that the optimal supporting time of the characteristic point in the underground plant of Xiangjiaba hydro-power station is 5-8 d,the long-term stability time of the typical section is 126 d,and the corresponding largest creep deformation is 24.30 mm. While the cavern is supported,the cavern deformation is significantly reduced and the stress states of the surrounding rock masses are remarkably improved. 展开更多
关键词 large-scale underground plant rheological mechanics optimal supporting time maximum creep deformation long-termstability long-term strength
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Long-term acupuncture treatment has a multitargeting regulation on multiple brain regions in rats with Alzheimer's disease:a positron emission tomography study 被引量:3
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作者 Yang-jia Lu Xiao-wen Cai +9 位作者 Gui-feng Zhang Yong Huang Chun-zhi Tang Bao-ci Shan Shao-yang Cui Jun-qi Chen Shan-shan Qu Zheng Zhong Xin-sheng Lai Genevieve Zara Steiner 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第7期1159-1165,共7页
The acute effect of acupuncture on Alzheimer's disease,i.e.,on brain activation during treatment,has been reported.However,the effect of long-term acupuncture on brain activation in Alzheimer's disease is unclear.Th... The acute effect of acupuncture on Alzheimer's disease,i.e.,on brain activation during treatment,has been reported.However,the effect of long-term acupuncture on brain activation in Alzheimer's disease is unclear.Therefore,in this study,we performed long-term needling at Zusanli(ST36)or a sham point(1.5 mm lateral to ST36)in a rat Alzheimer's disease model,for 30 minutes,once per day,for 30 days.The rats underwent 18F-fluorodeoxyglucose positron emission tomography scanning.Positron emission tomography images were processed with SPM2.The brain areas activated after needling at ST36 included the left hippocampus,the left orbital cortex,the left infralimbic cortex,the left olfactory cortex,the left cerebellum and the left pons.In the sham-point group,the activated regions were similar to those in the ST36 group.However,the ST36 group showed greater activation in the cerebellum and pons than the sham-point group.These findings suggest that long-term acupuncture treatment has targeted regulatory effects on multiple brain regions in rats with Alzheimer's disease. 展开更多
关键词 nerve regeneration NEURODEGENERATION ACUPUNCTURE Zusanli (ST36) Alzheimer's disease long-term treatment positron emissiontomography rat mechanism targeting effect compensation multi-target regulation neural regeneration
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Full-scale multi-functional test platform for investigating mechanical performance of track–subgrade systems of high-speed railways 被引量:2
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作者 Wanming Zhai Kaiyun Wang +3 位作者 Zhaowei Chen Shengyang Zhu Chengbiao Cai Gang Liu 《Railway Engineering Science》 2020年第3期213-231,共19页
Motivated by the huge practical engineering demand for the fundamental understanding of mechanical characteristics of high-speed railway infrastructure,a fullscale multi-functional test platform for high-speed railway... Motivated by the huge practical engineering demand for the fundamental understanding of mechanical characteristics of high-speed railway infrastructure,a fullscale multi-functional test platform for high-speed railway track–subgrade system is developed in this paper,and its main functions for investigating the mechanical performance of track–subgrade systems are elaborated with three typical experimental examples.Comprising the full-scale subgrade structure and all the five types of track structures adopted in Chinese high-speed railways,namely the CRTS I,the CRTS II and the CRTS III ballastless tracks,the double-block ballastless track and the ballasted track,the test platform is established strictly according to the construction standard of Chinese high-speed railways.Three kinds of effective loading methods are employed,including the real bogie loading,multi-point loading and the impact loading.Various types of sensors are adopted in different components of the five types of track–subgrade systems to measure the displacement,acceleration,pressure,structural strain and deformation,etc.Utilizing this test platform,both dynamic characteristics and long-term performance evolution of high-speed railway track–subgrade systems can be investigated,being able to satisfy the actual demand for large-scale operation of Chinese high-speed railways.As examples,three typical experimental studies are presented to elucidate the comprehensive functionalities of the full-scale multi-functional test platform for exploring the dynamic performance and its long-term evolution of ballastless track systems and for studying the long-term accumulative settlement of the ballasted track–subgrade system in high-speed railways.Some interesting phenomena and meaningful results are captured by the developed test platform,which provide a useful guidance for the scientific operation and maintenance of high-speed railway infrastructure. 展开更多
关键词 Full-scale test High-speed railway Track–subgrade system Ballastless track Ballasted track mechanical performance long-term performance evolution Damage and degradation
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Supporting structure failure caused by the squeezing tunnel creep and its reinforcement measure 被引量:2
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作者 ZHAO Jin-peng TAN Zhong-sheng +1 位作者 LI Lei WANG Xiu-ying 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1774-1789,共16页
Tunnels deeply buried have high crustal stress and are prone to large deformation disasters when encountering soft rock.The large deformation phenomenon during the construction process of the Maoxian Tunnel on the Che... Tunnels deeply buried have high crustal stress and are prone to large deformation disasters when encountering soft rock.The large deformation phenomenon during the construction process of the Maoxian Tunnel on the Chengdu-Lanzhou Railway is particularly evident.This article focuses on the large deformation problem of the No.1 inclined shaft of the Maoxian Tunnel,and uses on-site monitoring methods to explore the reasons for tunnel structure failure,and analyzes the mechanical behavior of the tunnel structure.By using numerical simulation methods,the effectiveness of the second-layer support in resisting creep loads in tunnels was studied,and the influence of the construction time of the secondlayer support on the mechanical properties of the tunnel was discussed.The results indicate that the first-layer support in the tunnel is a structural failure caused by asymmetric deformation caused by creep,while the second-layer support has a good effect on resisting creep loads.The research results can provide a technical reference for deformation control of squeezing tunnels. 展开更多
关键词 Squeezing tunnel mechanical responses long-term creep Second-layer support On-site monitoring
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A robust autoregressive long-term spatiotemporal forecasting framework for surrogate-based turbulent combustion modeling via deep learning 被引量:1
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作者 Sipei Wua Haiou Wang Kai Hong Luo 《Energy and AI》 EI 2024年第1期300-311,共12页
This paper systematically develops a high-fidelity turbulent combustion surrogate model using deep learning.We construct a surrogate model to simulate the turbulent combustion process in real time,based on a state-oft... This paper systematically develops a high-fidelity turbulent combustion surrogate model using deep learning.We construct a surrogate model to simulate the turbulent combustion process in real time,based on a state-ofthe-art spatiotemporal forecasting neural network.To address the issue of shifted distribution in autoregressive long-term prediction,two training techniques are proposed:unrolled training and injecting noise training.These techniques significantly improve the stability and robustness of the model.Two datasets of turbulent combustion in a combustor with cavity and a vitiated co-flow burner(Cabra burner)have been generated for model validation.The effects of model architecture,unrolled time,noise amplitude,and training dataset size on the long-term predictive performance are explored.The well-trained model can be applicable to new cases by extrapolation and give spatially and temporally consistent results in long-term predictions for turbulent reacting flows that are highly unsteady. 展开更多
关键词 Turbulent combustion Detailed reaction mechanism Transient simulation Deep neural network Spatiotemporal series prediction long-term forecast stability
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探索建立解决相对贫困的长效机制——深入学习贯彻党的十九届四中全会精神 被引量:3
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作者 吴宁 宁甜甜 孙鲁 《南昌航空大学学报(社会科学版)》 2020年第1期31-40,共10页
党的十九届四中全会释放了"建立解决相对贫困的长效机制"信号,为消除绝对贫困后的扶贫工作指明了方向。2020年后,我国扶贫工作将从重点消除绝对贫困向全面应对相对贫困过渡,我国与相对贫困的斗争经验也将成为其他国家的有益借... 党的十九届四中全会释放了"建立解决相对贫困的长效机制"信号,为消除绝对贫困后的扶贫工作指明了方向。2020年后,我国扶贫工作将从重点消除绝对贫困向全面应对相对贫困过渡,我国与相对贫困的斗争经验也将成为其他国家的有益借鉴,继续为世界减贫事业提供中国智慧、中国方案。2020年后,我国相对贫困伴随经济社会的变化而具有长期性、广泛性和多维性的特征。要建立解决相对贫困的长效机制,需要强化党的领导机制、协同多元主体治理机制、创新多维动态化的工作机制、建立解决相对贫困与乡村振兴有效衔接机制、改善持续增收机制、优化人力资本投资机制、构建多重保障机制、健全订单式的要素整合机制,在解决相对贫困中把中国特色社会主义制度坚持好、完善好、发展好,使其更加成熟更加定型,引领世界减贫事业。 展开更多
关键词 十九届四中全会 相对贫困 长效机制
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Chronic Response of Waste Activated Sludge Fermentation to Titanium Dioxide Nanoparticles 被引量:2
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作者 陈银广 牧辉 郑雄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第10期1162-1167,共6页
Due to the large-scale production and wide applications, many nanoparticles(NPs) enter wastewater treatment plants and accumulate in activated sludge. It is reported that titanium dioxide(Ti O2) NPs show severe damage... Due to the large-scale production and wide applications, many nanoparticles(NPs) enter wastewater treatment plants and accumulate in activated sludge. It is reported that titanium dioxide(Ti O2) NPs show severe damage to many model microbes. However, it is still unknown whether the long-term(e.g., 100 d) presence of Ti O2 NPs would affect the performance of sludge fermentation. In this study, long-term exposure experiments(105 d)were conducted to investigate the potential risk of Ti O2 NPs to sludge fermentation system. It is found that the presence of environmentally relevant [6 mg·(g TSS)-1] and higher [150 mg·(g TSS)-1] concentrations of Ti O2 NPs does not affect methane production from sludge fermentation. The analysis of fluorescence in situ hybridization indicates that these concentrations of Ti O2 NPs present marginal influences on abundances of bacteria and methanogenic archaea in sludge fermentation system. The viability of sludge microorganisms and activities of key enzymes related to methane production such as protease, acetate kinase, and coenzyme F420 are unchanged by the long-term presence of 6 and 150 mg·(g TSS)-1of Ti O2 NPs. Further investigations reveal that the insolubility of NPs and the protection role of sludge extracellular polymeric substances are the main reasons for the marginal influence of Ti O2 NPs on sludge fermentation. 展开更多
关键词 TITANIUM dioxide nanoparticles Waste ACTIVATED SLUDGE FERMENTATION long-term effect mechanism
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Effects of coarse and fine aggregates on long-term mechanical properties of sea sand recycled aggregate concrete 被引量:3
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作者 Jingwei YlNG Yijie HUANG +2 位作者 Xu GAO Xibo QI Yuedong SUN 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2021年第3期754-772,共19页
Typical effects of coarse and fine aggregates on the long-term properties of sea sand recycled aggregate concrete(SSRAC)are analyzed by a series of axial compression tests.Two different types of fine(coarse)aggregates... Typical effects of coarse and fine aggregates on the long-term properties of sea sand recycled aggregate concrete(SSRAC)are analyzed by a series of axial compression tests.Two different types of fine(coarse)aggregates are considered:sea sand and river sand(natural and recycled coarse aggregates).Variations in SSRAC properties at different ages are investigated.A novel test system is developed via axial compression experiments and the digital image correlation method to obtain the deformation field and crack development of concrete.Supportive results show that the compressive strength of SSRAC increase with decreasing recycled coarse aggregate replacement percentage and increasing sea sand chloride ion content.The elastic modulus of SSRAC increases with age.However,the Poisson’s ratio reduces after 2 years.Typical axial stress-strain curves of SSRAC vary with age.Generally,the effect of coarse aggregates on the axial deformation of SSRAC is clear;however,the deformation differences between coarse aggregate and cement mortar reduce by adopting sea sand.The aggregate type changes the crack characteristics and propagation of SSRAC.Finally,an analytical expression is suggested to construct the long-term stress-strain curve of SSRAC. 展开更多
关键词 sea sand recycled aggregate concrete recycled coarse aggregate replacement percentage sea sand chloride ion content long-term mechanical properties stress-strain curve
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Effect of Phase Transformation During Long-Term Solution Treatment on Microstructure,Mechanical Properties,and Bio-corrosion Behavior of Mg–5Zn–1.5Y Cast Alloy 被引量:3
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作者 H.Jafari E.Heidari +1 位作者 A.Barabi M.Dashti Kheirabadi 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2018年第6期561-574,共14页
The influence of long-term solution treatment for various intervals on the microstructure,mechanical properties,and corrosion resistance of the as-cast Mg–5Zn–1.5Y alloy was investigated.Variation of secondary phase... The influence of long-term solution treatment for various intervals on the microstructure,mechanical properties,and corrosion resistance of the as-cast Mg–5Zn–1.5Y alloy was investigated.Variation of secondary phases was studied during solution treatment through thermal analysis test and thermodynamic calculations.Tensile and hardness tests,as well as polarization and immersion tests,were performed to evaluate the mechanical properties and corrosion behavior of the ascast and heat-treated alloy,respectively.Results show that solution treatment transforms I-phaseinto W-phaseas well as dissolves it into the a-Mg matrix to some extent;therefore,the amount of W-phase increases.Moreover,prolonged solution treatment decreases the volume fraction of the phases.In the first stage of solution treatment for 14 h,the tensile properties significantly increase due to the incomplete phase transformation.Although long-term solution treatment sharply decreases the tensile and hardness properties of the alloy,it improves the corrosion resistance due to the transformation of I-phase into W-phase.In fact,it decreases corrosion potential and simultaneously dissolves intermetallic compounds into the a-Mg matrix,resulting in the reduction in galvanic microcells between the matrix and compounds.It is found that the optimum time for long-term solution treatment is 14 h,which improves both corrosion behavior and mechanical properties. 展开更多
关键词 Magnesium alloy long-term solution treatment Microstructure mechanical properties Bio-corrosion
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Laboratory creep tests for time-dependent properties of a marble in Jinping Ⅱ hydropower station 被引量:5
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作者 Xiaojun Zhao Bingrui Chen +2 位作者 Hongbo Zhao Binghui Jie Zhengfang Ning 《Journal of Rock Mechanics and Geotechnical Engineering》 2012年第2期168-176,共9页
In order to investigate the time-dependent behaviors of deep hard rocks in the diversion tunnel of Jinping II hydropower station, uniaxial creep tests were carried out by using the triaxial testing machine RC-2000. Th... In order to investigate the time-dependent behaviors of deep hard rocks in the diversion tunnel of Jinping II hydropower station, uniaxial creep tests were carried out by using the triaxial testing machine RC-2000. The axial compressive load was applied step by step and each creep stage was kept for over several days. Test results show that: (1) The lateral deformation of rock specimens is 2-3 times the axial compressive deformation and accelerates drastically before damage, which may be employed as an indicator to predict the excavation-induced instability of rocks. (2) The resultant deformation changes from compression to expansion when the Poisson's ratio is larger than 0.5, indicating the starting point of damage. (3) In the step-loading stages, the Poisson's ratio approximately remains constant; under constantly imposed load, the Poisson's ratio changes with elapsed time, growing continuously before the specimen is damaged. (4) When the applied load reaches a certain threshold value, the rock deteriorates with time, and the strength of rocks approximately has a negative exponent relation with time. (5) The failure modes of the deep marble are different in long- and short-term loading conditions. Under the condition of short-term loading, the specimen presents a mode of tensile failure; while under the condition of long-term loading, the specimen presents a mode of shear failure, followed by tensile failure. 展开更多
关键词 time-dependent mechanical behaviors MARBLE long-term strength the Poisson's ratio of rocks rock creep
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The Study on the Mechanical Properties of Optical Fiber With Long-Term Time Aging
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作者 Sung Koog Oh Young Seok Kim Jae Ho Lee 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期100-101,共2页
The fiber properties depending on the coating thickness and long-term time aging were investigated. The coating strip forces of optical fiber were strongly increased with secondary coating thickness. But it did not ch... The fiber properties depending on the coating thickness and long-term time aging were investigated. The coating strip forces of optical fiber were strongly increased with secondary coating thickness. But it did not change with time aging up to 90 days. The tensile strength and stress corrosion parameters of coated fiber were increased with time aging also but the increasing rate was quite different depending on the coating 展开更多
关键词 of with in were The Study on the mechanical Properties of Optical Fiber With long-term Time Aging on
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