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日本第五次能源基本计划对我国的启示 预览
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作者 张所续 《中国能源》 2020年第1期25-30,47,共7页
日本高度重视能源安全,2018年制定第五次能源基本计划,采取立足国内挖潜,打造“核心企业”,开展全方位的“资源外交”,提升国际话语权构建国家、民间、第三方储备体系,促进全面节能,全面建设“氢社会”,推进能源体制改革,促进化石燃料... 日本高度重视能源安全,2018年制定第五次能源基本计划,采取立足国内挖潜,打造“核心企业”,开展全方位的“资源外交”,提升国际话语权构建国家、民间、第三方储备体系,促进全面节能,全面建设“氢社会”,推进能源体制改革,促进化石燃料的高效、稳定利用等措施,构建多层次、多样化、灵活的能源供需结构。中国经济发展进入新常态,需要坚持绿色发展,构建新型能源体系;加强能源节约,助推能源消费革命;大力发展电力,提高电气化水平;立足国内挖潜,构建多元化的战略储备体系;落实“一带一路”倡议,实施资源外交战略;加强能源技术革命,提高国际话语权。 展开更多
关键词 能源 可再生能源 能源安全
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Technology of Eliminating White Smoke from Flue Gas 预览
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作者 Ping ZHAO Jinghai TAN +1 位作者 Minghao WANG Hongliang BAO 《气象与环境研究:英文版》 CAS 2020年第1期66-69,共4页
Based on the corresponding relationship chart of saturation humidity and temperature of wet flue gas,the formation mechanism of"white smoke plume"and the technology of eliminating white smoke from flue gas w... Based on the corresponding relationship chart of saturation humidity and temperature of wet flue gas,the formation mechanism of"white smoke plume"and the technology of eliminating white smoke from flue gas were analyzed.Besides,the energy balance of each elimination technology was calculated according to the theoretical formulas,and"energy saving"was compared.The technology of eliminating white smoke from flue gas needs to solve the problems of"emission reduction"and"energy conservation"in industrial enterprises.It brings new ideas and directions to enterprises for"energy conservation and emission reduction",eases the pressure on enterprises to protect the environment,improves enterprises'use efficiency of primary energy,and provides a reliable choice for enterprises to survive and enhance their competitiveness.In addition,it can effectively solve the dehumidification and elimination of wet flue gas,not only eliminate the pollution from white smoke plume,but also achieve environmental protection up-to-standard and ultra-low near zero emission at low cost,enhance the efficiency of coal combustion,in particular recover the moisture and residual heat in flue gas,and solve the contradiction between the environment and development. 展开更多
关键词 Elimination of white smoke Emission reduction Energy conservation White wet smoke plume Energy Environment
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Contributions of optimized tensor interactions on the binding energies of nuclei 预览
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作者 Di Wu Chun-Lin Bai +2 位作者 H.Sagawa Zeng-Qiang Song Huan-Qiao Zhang 《核技术:英文版》 SCIE CAS CSCD 2020年第2期11-19,共9页
The tensor parts of Skyrme interactions are constrained from the collective charge-exchange spin-dipole and Gamow-Teller excitation energies in 90Zr and 208Pb,together with the isotopic dependence of energy splitting ... The tensor parts of Skyrme interactions are constrained from the collective charge-exchange spin-dipole and Gamow-Teller excitation energies in 90Zr and 208Pb,together with the isotopic dependence of energy splitting between proton h11=2 and g7=2 single-particle orbits along the Z=50 isotopes.With the optimized tensor interactions,the binding energies of spherical or weakly deformed nuclei with A=54-228 are studied systematically.The present results show that the global effect of tensor interaction is attractive and systematically increases the binding energies of all these nuclei and makes the nuclei more bound.The root mean squared deviation of the calculated binding energies from the experimental values is significantly improved by the optimized tensor interactions,and the contribution of the tensor interaction to the binding energy is estimated. 展开更多
关键词 Tensor force Binding energy Gamow-Teller transition Spin-dipole transition Single-particle energy differences
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Vibration reduction evaluation of a linear system with a nonlinear energy sink under a harmonic and random excitation 预览
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作者 Jiren XUE Yewei ZHANG +1 位作者 Hu DING Liqun CHEN 《应用数学和力学:英文版》 SCIE EI CSCD 2020年第1期1-14,共14页
The nonlinear behaviors and vibration reduction of a linear system with a nonlinear energy sink(NES)are investigated.The linear system is excited by a harmonic and random base excitation,consisting of a mass block,a l... The nonlinear behaviors and vibration reduction of a linear system with a nonlinear energy sink(NES)are investigated.The linear system is excited by a harmonic and random base excitation,consisting of a mass block,a linear spring,and a linear viscous damper.The NES is composed of a mass block,a linear viscous damper,and a spring with ideal cubic nonlinear stiffness.Based on the generalized harmonic function method,the steady-state Fokker-Planck-Kolmogorov equation is presented to reveal the response of the system.The path integral method based on the Gauss-Legendre polynomial is used to achieve the numerical solutions.The performance of vibration reduction is evaluated by the displacement and velocity transition probability densities,the transmissibility transition probability density,and the percentage of the energy absorption transition probability density of the linear oscillator.The sensitivity of the parameters is analyzed for varying the nonlinear stiffness coefficient and the damper ratio.The investigation illustrates that a linear system with NES can also realize great vibration reduction under harmonic and random base excitations and random bifurcation may appear under different parameters,which will affect the stability of the system. 展开更多
关键词 nonlinear energy sink(NES) Gauss-Legendre polynomial TRANSMISSIBILITY percentage of energy absorption
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Relative energy zero ratio-based approach for identifying pulse-like ground motions 预览
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作者 Liu Ping Li Ning +2 位作者 Ma Hua Xie Lili Zhou Baofeng 《地震工程与工程振动:英文版》 SCIE EI CSCD 2020年第1期1-16,共16页
Pulse-like ground motions are capable of inflicting significant damage to structures. Efficient classification of pulse-like ground motion is of great importance when performing the seismic assessment in near-fault re... Pulse-like ground motions are capable of inflicting significant damage to structures. Efficient classification of pulse-like ground motion is of great importance when performing the seismic assessment in near-fault regions. In this study, a new method for identifying the velocity pulses is proposed, based on different trends of two parameters: the short-time energy and the short-time zero crossing rate of a ground motion record. A new pulse indicator, the relative energy zero ratio(REZR), is defined to qualitatively identify pulse-like features. The threshold for pulse-like ground motions is derived and compared with two other identification methods through statistical analysis. The proposed procedure not only shows good accuracy and efficiency when identifying pulse-like ground motions but also exhibits good performance for classifying records with high-frequency noise and discontinuous pulses. The REZR method does not require a waveform formula to express and fit the potential velocity pulses;it is a purely signal-based classification method. Finally, the proposed procedure is used to evaluate the contribution of pulse-like motions to the total input energy of a seismic record, which dramatically increases the seismic damage potential. 展开更多
关键词 pulse-like ground motion velocity pulse relative energy zero-crossing ratio short-time input energy shorttime zero crossing rate
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5Ws of Green and Sustainable Software
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作者 Coral Calero Javier Mancebo +4 位作者 Felix Garcia Maria Angeles Moraga Jose Alberto Garcia Berna Jose Luis Fernandez-Aleman Ambrosio Toval 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2020年第3期401-414,共14页
Green and Sustainable Software has emerged as a new and highly active area in the software community.After several years of research and work,we believe that it is now necessary to obtain a general snapshot of how the... Green and Sustainable Software has emerged as a new and highly active area in the software community.After several years of research and work,we believe that it is now necessary to obtain a general snapshot of how the research in this area is evolving.To do so,we have applied the 5 Ws(why,when,who,where,and what),a formula for getting the complete story on a subject.We have therefore carried out a study,using 542 publications related to Green and Sustainable Software research;these were recovered using SCOPUS.The results obtained allow us to conclude that it is important to identify key elements of the research to allow researchers be fully aware of the state of the research on Green and Sustainable Software(why);the study uses papers published between 2000 and the beginning of November 2018(when);the most prolific authors are mainly from Europe,although the USA is the most active country,Green and Sustainable Software being a very interactive area with a good number of multinational publications(who);the top five keywords related to sustainable aspects are Green Software,Green IT,Software Sustainability,Energy Consumption,and Energy Efficiency(what);finally,as regards the places authors prefer to publish in,there is almost a complete balance between conferences and journals,with a trend towards an increase in the number of publications(where). 展开更多
关键词 Green Software Sustainable Software Software Engineering Software Sustainability Energy Efficiency Energy Utilization
Ultrastable and High‑Performance Silk Energy Harvesting Textiles 预览
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作者 Chao Ye Shaojun Dong +1 位作者 Jing Ren Shengjie Ling 《纳微快报:英文版》 CAS CSCD 2020年第1期143-157,共15页
Energy harvesting textiles(EHTs)have attracted much attention in wearable electronics and the internet-of-things for real-time mechanical energy harvesting associated with human activities.However,to satisfy practical... Energy harvesting textiles(EHTs)have attracted much attention in wearable electronics and the internet-of-things for real-time mechanical energy harvesting associated with human activities.However,to satisfy practical application requirements,especially the demand for long-term use,it is challenging to construct an energy harvesting textile with elegant trade-off between mechanical and triboelectric performance.In this study,an energy harvesting textile was constructed using natural silk inspired hierarchical structural designs combined with rational material screening;this design strategy provides multiscale opportunities to optimize the mechanical and triboelectric performance of the final textile system.The resulting EHTs with traditional advantages of textiles showed good mechanical properties(tensile strength of 237±13 MPa and toughness of 4.5±0.4 MJ m−3 for single yarns),high power output(3.5 mW m−2),and excellent structural stability(99%conductivity maintained after 2.3 million multi-type cyclic deformations without severe change in appearance),exhibiting broad application prospects in integrated intelligent clothing,energy harvesting,and human-interactive interfaces. 展开更多
关键词 SILK Energy harvesting textile Co-wrapped yarn Triboelectric nanogenerator
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Synthesis and characterization of salt-impregnated anodic aluminum oxide composites for low-grade heat storage 预览
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作者 Bengisu Yilmaz Behiye Yüksel +2 位作者 Gökhan Orhan Devrim Aydin Zafer Utlu 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2020年第1期112-118,共7页
Thermochemical heat storage(THS)systems have recently attracted a lot of attention in research and development.In this study,an anodic aluminum oxide(AAO)template,fabricated by a two-step anodization method,was used f... Thermochemical heat storage(THS)systems have recently attracted a lot of attention in research and development.In this study,an anodic aluminum oxide(AAO)template,fabricated by a two-step anodization method,was used for the first time as the matrix material for a THS system.Different salts were studied as thermochemical materials for their suitability in low-grade heat storage application driven by solar energy for an open system.Compositions were prepared by absorbing CaCl2,MgCl2,LiCl,LiNO3 and mixtures of these salts under a vacuum in an AAO matrix.Field Emission Scanning Electron Microscopy was used to examine the morphology of the produced AAO composites.Thermal energy storage capacities of the composites were characterized using a differential scanning calorimeter.Characterization analysis showed that anodized Al plates were suitable matrix materials for THS systems,and composite sorbent prepared with a 1:1 ratio LiCl/LiNO3 salt mixture had the highest energy value among all composites,with an energy density of 468.1 k J·kg-1. 展开更多
关键词 thermal energy storage salt impregnation thermochemical heat storage ANODIZING salt in matrix
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Cooperative Privacy Provisioning for Energy Harvesting Based Cognitive Multi-Relay Networks 预览
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作者 Dawei Wang Wei Liang +2 位作者 Xiaoyu Hu Daosen Zhai Di Zhang 《中国通信:英文版》 SCIE CSCD 2020年第2期125-137,共13页
In order to provide privacy provisioning for the secondary information,we propose an energy harvesting based secure transmission scheme for the cognitive multi-relay networks.In the proposed scheme,two secondary relay... In order to provide privacy provisioning for the secondary information,we propose an energy harvesting based secure transmission scheme for the cognitive multi-relay networks.In the proposed scheme,two secondary relays harvest energy to power the secondary transmitter and assist the secondary secure transmission without interfere the secondary transmission.Specifically,the proposed secure transmission policy is implemented into two phases.In the first phase,the secondary transmitter transmits the secrecy information and jamming signal through the power split method.After harvesting energy from a fraction of received radio-frequency signals,one secondary relay adopts the amplify-and-forward relay protocol to assist the secondary secure transmission and the other secondary relay just forwards the new designed jamming signal to protect the secondary privacy information and degrade the jamming interference at the secondary receiver.For the proposed scheme,we first analyze the average secrecy rate,the secondary secrecy outage probability,and the ergodic secrecy rate,and derive their closed-form expressions.Following the above results,we optimally allocate the transmission power such that the secrecy rate is maximized under the secrecy outage probability constraint.For the optimization problem,an AI based simulated annealing algorithm is proposed to allocate the transmit power.Numerical results are presented to validate the performance analytical results and show the performance superiority of the proposed scheme in terms of the average secrecy rate. 展开更多
关键词 cognitive radio networks energy harvesting RELAY security
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Classical solutions to relativistic Burgers equations in FLRW space-times
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作者 Saisai Huo Changhua Wei 《中国科学:数学英文版》 SCIE CSCD 2020年第2期357-370,共14页
We are interested in the classical solutions to the Cauchy problem of relativistic Burgers equations evolving in Friedmann-Lemat?tre-Robertson-Walker(FLRW)space-times,which are spatially homogeneous,isotropic expandin... We are interested in the classical solutions to the Cauchy problem of relativistic Burgers equations evolving in Friedmann-Lemat?tre-Robertson-Walker(FLRW)space-times,which are spatially homogeneous,isotropic expanding or contracting universes.In such kind of space-times,we first derive the relativistic Burgers equations from the relativistic Euler equations by letting the pressure be zero.Then we can show the global existence of the classical solution to the derived equation in the accelerated expanding space-times with small initial data by the method of characteristics when the spacial dimension n=1 and the energy estimate when n 2,respectively.Furthermore,we can also show the lifespan of the classical solution by similar methods when the expansion rate of the space-times is not so fast. 展开更多
关键词 FLRW space-times relativistic Burgers equations CHARACTERISTICS energy estimate
回归模型法测定生长期云南半细毛羊的能量需要量 预览
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作者 李湘 路明丽 +6 位作者 洪琼花 薛白 武渝瀚 胡安海 王之盛 王立志 彭全辉 《动物营养学报》 CAS CSCD 北大核心 2020年第1期447-454,共8页
本试验旨在确定生长期云南半细毛羊的能量需要量,为该品种羊饲粮的配制提供理论数据。试验采用饲养试验和消化代谢试验相结合的方法进行。选择45只体况良好、体重(33.30±1.77)kg、10月龄的云南半细毛羊羯羊,随机分为5组,每组9个重... 本试验旨在确定生长期云南半细毛羊的能量需要量,为该品种羊饲粮的配制提供理论数据。试验采用饲养试验和消化代谢试验相结合的方法进行。选择45只体况良好、体重(33.30±1.77)kg、10月龄的云南半细毛羊羯羊,随机分为5组,每组9个重复,每个重复1只羊。5组试验羊所喂饲粮代谢能水平分别为8.00、8.60、9.20、9.80、10.40 MJ/kg,其他营养水平基本一致,预试期15 d,正试期30 d。在饲养试验正试期的第7天于每组中随机选择5只羊于代谢笼内,采用全收粪尿法进行为期7 d的消化代谢试验。结果显示:1)饲粮能量水平对生长期云南半细毛羊的终末体重、干物质采食量和料重比有显著影响(P<0.05),随着饲粮能量水平的提高,料重比显著下降(P<0.05);2)饲粮能量水平对生长期云南半细毛羊的总能表观消化率、总能代谢率和消化能代谢率有显著影响(P<0.05),总能表观消化率、总能代谢率和消化能代谢率随饲粮能量水平的提高而升高;3)生长期云南半细毛羊消化能(DE)和代谢能(ME)需要量与代谢体重(W 0.75)和平均日增重(ADG)的回归方程分别为DE(MJ/d)=0.6780W 0.75+0.028ADG(P<0.001,R^2=0.999)、ME(MJ/d)=0.5707W 0.75+0.025ADG(P<0.001,R^2=0.999)。根据以上结果得出,生长期云南半细毛羊的维持ME需要量为0.5707 MJ/(kg W 0.75·d),每增重100 g的ME需要量为2.5 MJ。 展开更多
关键词 云南半细毛羊 生长期 能量 需要量
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Lazy Scheduling Based Disk Energy Optimization Method
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作者 Yong Dong Juan Chen +3 位作者 Yuhua Tang Junjie Wu Huiquan Wang Enqiang Zhou 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2020年第2期203-216,共14页
Reducing the energy consumption of the storage systems disk read/write requests plays an important role in improving the overall energy efficiency of high-performance computing systems.We propose a method to reduce di... Reducing the energy consumption of the storage systems disk read/write requests plays an important role in improving the overall energy efficiency of high-performance computing systems.We propose a method to reduce disk energy consumption by delaying the dispatch of disk requests to the end of a time window,which we call time window-based lazy scheduling.We prove that sorting requests within a single time window can reduce the disk energy consumption,and we discuss the relationship between the size of the time window and the disk energy consumption,proving that the energy consumption is highly likely to decrease with increasing window size.To exploit this opportunity,we propose the Lazy Scheduling based Disk Energy Optimization(LSDEO)algorithm,which adopts a feedback method to periodically adjust the size of the time window,and minimizes the local disk energy consumption by sorting disk requests within each time window.We implement the LSDEO algorithm in an OS kernel and conduct both simulations and actual measurements on the algorithm,confirming that increasing the time window increases disk energy savings.When the average request arrival rate is 300 and the threshold of average request response time is 50 ms,LSDEO can yield disk energy savings of 21.5%. 展开更多
关键词 high-performance computing system storage systems disk energy savings lazy scheduling disk seek time window
非对易相空间中的狄拉克振子的能级和Wigner函数 预览
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作者 吕腾博 刘丽 +2 位作者 刘卫华 李昕 王小力 《大学物理》 2020年第1期1-4,17,共5页
非对易几何、弦论和圈量子引力理论的发展,使非对易空间受到越来越多的关注.非对易量子理论不同于平常的量子理论,它是弦尺度下的特殊的物理效应,处理非对易量子力学问题需要特殊方法.本文首先介绍了Moyal方程与Wigner函数,利用Moyal-W... 非对易几何、弦论和圈量子引力理论的发展,使非对易空间受到越来越多的关注.非对易量子理论不同于平常的量子理论,它是弦尺度下的特殊的物理效应,处理非对易量子力学问题需要特殊方法.本文首先介绍了Moyal方程与Wigner函数,利用Moyal-Weyl乘法与Bopp变换将H(x,p)变换成^H(^x,^p),考虑坐标—坐标、动量—动量的非对易性,实现对非对易相空间中星乘本征方程的求解.并利用非对易相空间量子力学的代数关系,讨论了非对易相空间中狄拉克振子的Wigner函数和能级,研究结果发现非对易相空间中狄拉克振子的能级明显依赖于非对易参数. 展开更多
关键词 狄拉克振子 非对易相空间 WIGNER函数 能级
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Bethe–Weizs?cker semiempirical mass formula coefficients 2019update based on AME2016 预览
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作者 Djelloul Benzaid Salaheddine Bentridi +1 位作者 Abdelkader Kerraci Naima Amrani 《核技术:英文版》 SCIE CAS CSCD 2020年第1期88-93,共6页
In the present work, the classical Bethe–Weizs?cker(BW) mass formula with five energy terms is revisited and updated. We use the least-squares adjustments on the binding energy of 2497 different nuclides from the las... In the present work, the classical Bethe–Weizs?cker(BW) mass formula with five energy terms is revisited and updated. We use the least-squares adjustments on the binding energy of 2497 different nuclides from the last update of the atomic mass evaluation,AME2016 published in March 2017, to provide a new set of energy coefficients of the mass formula. The obtained set of formula coefficients allowed us to reproduce most of the experimental values of the binding energies for each nucleus with A ≥50. The comparison between the binding energies provided with updated mass formula and those of AME2016 on the one hand, and those of previous works,on the other hand, yields relative errors that oscillate between less than 0.05% and 1.5%. The revisited BW formula is in very good agreement with the experimental data. 展开更多
关键词 Binding energy of atomic nuclei Mass formula coefficients AME2016 Least-squares adjustments
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区块链技术在电力领域应用场景的探索分析 预览
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作者 梅文明 王栋 《电力信息与通信技术》 2020年第2期21-29,共9页
区块链作为一种新兴技术,被认为是继蒸汽机、电力、互联网之后的下一代颠覆性的核心技术,正在逐步改变金融、身份认证、防伪等传统技术领域。电力行业是支撑国民经济和社会发展的基础能源产业,文章基于区块链关键技术,探讨区块链技术在... 区块链作为一种新兴技术,被认为是继蒸汽机、电力、互联网之后的下一代颠覆性的核心技术,正在逐步改变金融、身份认证、防伪等传统技术领域。电力行业是支撑国民经济和社会发展的基础能源产业,文章基于区块链关键技术,探讨区块链技术在电力领域的应用前景。首先分析了区块链原理以及在相关行业的应用场景,然后对区块链在电力行业应用情况和应用场景进行研究分析,最后对区块链未来的应用前景与发展趋势进行探索展望,以期引领区块链技术在能源互联网领域的典型应用。 展开更多
关键词 区块链 能源 电网
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单原子光催化剂的合成、表征及在环境与能源领域的应用 预览
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作者 李惠惠 张圆正 +2 位作者 代云容 于艳新 殷立峰 《材料导报》 EI CAS CSCD 北大核心 2020年第3期56-68,共13页
绿色清洁的光催化技术可降解污染物、生产能源,是解决环境与能源问题的重要手段,但限于光催化材料成本及效率方面,难以实现大规模应用。近年来单原子光催化剂的诞生和发展为这一领域注入了新的活力,其合成、表征及应用的相关研究成为材... 绿色清洁的光催化技术可降解污染物、生产能源,是解决环境与能源问题的重要手段,但限于光催化材料成本及效率方面,难以实现大规模应用。近年来单原子光催化剂的诞生和发展为这一领域注入了新的活力,其合成、表征及应用的相关研究成为材料、化学、环境、能源等诸多领域的热点。与传统负载型光催化剂相比,单原子光催化剂表面的金属粒子的分散度达到原子尺寸,可呈现更高的催化活性和选择性,但对合成策略、表征技术和应用途径提出了更高的挑战:合成方面的主要障碍在于金属单原子的高表面能导致合成过程中的失稳团聚而丧失其单原子形态;传统的表征技术也缺乏对单原子形貌、结构及化学环境的解析能力;目前对单原子光催化剂的应用研究多为传统研究领域的延伸,未能充分利用单原子的功能特性。这些问题成为制约其发展的关键,也是该领域的研究热点。国内外学者在单原子光催化材料合成、表征和应用领域做出了巨大努力,并取得了丰硕成果:(1)合成方面,针对单原子表面能高、易团聚的问题,改进了液相合成法、原子层沉积法等传统合成策略,引进了新的高温裂解、火焰喷雾、静电自组装等技术;(2)表征方面,先进的原子尺度分析技术如球差校正高分辨透射电镜(HAADF-STEM)、X射线吸收精细结构谱(XAFs)等以及密度泛函理论(DFT)的发展则有助于深入理解孤立金属单原子形态及化学结构;(3)单原子光催化剂目前已被成功应用于光解水制氢、光催化CO2还原、环境污染物降解以及合成氨等领域,获得了长足的发展。上述成果推进了光催化材料及催化理论的研究向原子级别深入,使其进一步贴近实用化。本文综述了近年来单原子光催化剂的合成方法、表征技术以及在环境和能源领域的应用情况。同时,总结了目前单原子光催化材料研究中存在的 展开更多
关键词 单原子 光催化剂 环境 污染物降解 能源
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基于CEEMDAN能量权重法的轴承故障诊断 预览
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作者 周亦人 邱小林 张兰 《轴承》 北大核心 2020年第1期43-47,共5页
针对强噪声干扰下轴承微弱故障特征难以通过单一的降噪或特征增强方法进行提取的问题,提出了一种基于时频谱分析的冲击能量增强的能量权重法,将噪声消除与特征增强2类方法进行融合,从而实现强噪声背景下微弱冲击的特征提取,并通过352226... 针对强噪声干扰下轴承微弱故障特征难以通过单一的降噪或特征增强方法进行提取的问题,提出了一种基于时频谱分析的冲击能量增强的能量权重法,将噪声消除与特征增强2类方法进行融合,从而实现强噪声背景下微弱冲击的特征提取,并通过352226X2-2Z型圆锥滚子轴承内圈故障的试验验证了该方法在实际应用中的有效性。 展开更多
关键词 滚动轴承 故障诊断 特征提取 CEEMDAN 能量 统计权重
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Spectral characteristic of laser-induced plasma in soil
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作者 余洋 赵南京 +2 位作者 兰智高 孟德硕 马明俊 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2020年第1期74-79,共6页
The spectral characteristic of laser-induced plasma in soil was studied in this work,laser-induced breakdown spectroscopy was used to analyze the spectral characteristic of plasma under the condition of different time... The spectral characteristic of laser-induced plasma in soil was studied in this work,laser-induced breakdown spectroscopy was used to analyze the spectral characteristic of plasma under the condition of different time delays and irradianccs.Moreover,the time evolution characteristics of plasma temperature and electron density were discussed.Within the time delay range of 0-5μs,the spectral intensity of the characteristic lines of Si I:288.158 nm,Ti I:336.126 nm.Al I:394.400 nm and Fe I:438.354 nm of the four main elements in two kinds of national standard soil decayed exponentially with time.The average lifetime of the spectral lines was nearly 1.56μs.Under the condition of different time delays,the spectral intensity of Pb I:405.78 nm in soil increased linearly with laser energy.However,the slope between the spectral intensity and laser energy decreased exponentially with the increase in time delay,from 4.91 to 0.99 during 0-5μs.The plasma temperature was calculated by the Boltzmann plot method and the electron density was obtained by inversion of the full width at half maximum of the spectrum.The plasma temperature decreased from 8900 K to 7800 K and the electron density decreased from 1.5 x 1Ol7cm-3 to 7.8 x lO16cm-3 in the range of 0-5μs. 展开更多
关键词 LIBS.soil delay time laser energy plasma temperature electron density
语言的力量与非暴力言语交流 预览
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作者 马书红 《科教文汇》 2020年第1期176-177,共2页
语言具有镜像功能,通过言说者的话语,我们可以窥见其内在世界和精神现实。此外,语言还有传递能量的功能,借助于语言的媒介作用,人的能量可以对个体和社会施加某种影响,从而参与人的内在现实与外部世界的创造与改造。人的语言的效能的大... 语言具有镜像功能,通过言说者的话语,我们可以窥见其内在世界和精神现实。此外,语言还有传递能量的功能,借助于语言的媒介作用,人的能量可以对个体和社会施加某种影响,从而参与人的内在现实与外部世界的创造与改造。人的语言的效能的大小取决于言说者的精神属性(爱、谦卑、尊重、温和等)的强弱。在日常的人际交往中,采用非暴力的、非评价性的言语与他人对话,可以营造和谐的交流氛围,解决实际的问题,达到有效的交际目的。 展开更多
关键词 语言 能量 镜像作用 非暴力交流
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调制周期对Al/MoO3反应薄膜热性能和发火性能的影响 预览
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作者 倪德彬 党鹏阳 +5 位作者 徐栋 于国强 陈利魁 朱雅红 解战锋 褚恩义 《含能材料》 EI CAS CSCD 北大核心 2020年第2期105-111,共7页
为了考察调制周期对反应薄膜性能的影响,采用磁控溅射技术制备了厚度为3μm,调制周期为50,150 nm和300 nm的Al/MoO3反应薄膜,采用差示扫描量热仪(DSC)探索了调制周期对Al/MoO3反应薄膜放热过程和反应活化能的影响;使用高速摄影和激光点... 为了考察调制周期对反应薄膜性能的影响,采用磁控溅射技术制备了厚度为3μm,调制周期为50,150 nm和300 nm的Al/MoO3反应薄膜,采用差示扫描量热仪(DSC)探索了调制周期对Al/MoO3反应薄膜放热过程和反应活化能的影响;使用高速摄影和激光点火技术研究了三种调制周期反应薄膜的燃烧速率,通过与半导体桥和桥丝融合形成含能点火器件,考察了调制周期对电流和电压发火感度的影响。结果显示调制周期由50 nm增加到300 nm时,Al/MoO3反应薄膜燃烧速率由5.35 m·s^-1降低到1.75 m·s^-1。三种调制周期(50,150,300 nm)Al/MoO3反应薄膜半导体桥点火器件的50%电流发火电流分别为1.44,1.74 A和1.87 A;Al/MoO3反应薄膜桥丝点火器件的50%发火电流分别为0.08,0.65 A和1.02 A;将Al/MoO3反应薄膜与半导体桥和桥丝换能元结合形成点火器件,在点火间隙为1 mm的情况下,能够点燃钝感点火药硼-硝酸钾(B-KNO3)药片,提升点火系统的点火能力和可靠性。 展开更多
关键词 调制周期 Al/MoO3反应薄膜 活化能 发火感度
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