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12.6μm-Thick Asymmetric Composite Electrolyte with Superior Interfacial Stability for Solid-State Lithium-Metal Batteries 被引量:2
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作者 Zheng Zhang Jingren Gou +4 位作者 Kaixuan Cui Xin Zhang Yujian Yao Suqing Wang Haihui Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期397-409,共13页
Solid-state lithium metal batteries(SSLMBs)show great promise in terms of high-energy-density and high-safety performance.However,there is an urgent need to address the compatibility of electrolytes with high-voltage ... Solid-state lithium metal batteries(SSLMBs)show great promise in terms of high-energy-density and high-safety performance.However,there is an urgent need to address the compatibility of electrolytes with high-voltage cathodes/Li anodes,and to minimize the electrolyte thickness to achieve highenergy-density of SSLMBs.Herein,we develop an ultrathin(12.6μm)asymmetric composite solid-state electrolyte with ultralight areal density(1.69 mg cm^(−2))for SSLMBs.The electrolyte combining a garnet(LLZO)layer and a metal organic framework(MOF)layer,which are fabricated on both sides of the polyethylene(PE)separator separately by tape casting.The PE separator endows the electrolyte with flexibility and excellent mechanical properties.The LLZO layer on the cathode side ensures high chemical stability at high voltage.The MOF layer on the anode side achieves a stable electric field and uniform Li flux,thus promoting uniform Li^(+)deposition.Thanks to the well-designed structure,the Li symmetric battery exhibits an ultralong cycle life(5000 h),and high-voltage SSLMBs achieve stable cycle performance.The assembled pouch cells provided a gravimetric/volume energy density of 344.0 Wh kg^(−1)/773.1 Wh L^(−1).This simple operation allows for large-scale preparation,and the design concept of ultrathin asymmetric structure also reveals the future development direction of SSLMBs. 展开更多
关键词 Solid-state lithium metal batteries Composite solid-state electrolyte Ultrathin asymmetric structure Pouch cells
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ASYMMETRICAL STRUCTURES OF THE TEMPERATURE AND HUMIDITY OF TROPICAL CYCLONES 被引量:2
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作者 杨涛 雷小途 汤杰 《Journal of Tropical Meteorology》 SCIE 2016年第3期296-304,共9页
Based on NCEP/CFSR 0.5° reanalysis data and the best track data from the Japan Tokyo Typhoon Center,composite and comparative analyses demonstrate the asymmetrical structures of the temperature and humidity in tr... Based on NCEP/CFSR 0.5° reanalysis data and the best track data from the Japan Tokyo Typhoon Center,composite and comparative analyses demonstrate the asymmetrical structures of the temperature and humidity in tropical cyclones over the Western North Pacific and the South China Sea from 1979 to 2010.The results are shown as follows.(1) With intensifying tropical cyclones,the flow field tends to become gradually more axisymmetric;however,the asymmetry of the specific humidity in the outer regions is more obvious.(2) In general,tropical cyclones have a non-uniform,vertical, "double warm-core" structure.The "warm-cores" in the lower level of weak tropical cyclones and in the higher level of strong tropical cyclones are the stronger of the two.(3) The distribution area of a "warm-core" is enhanced with cyclone intensification and tends to become more axisymmetric.At 200 hPa,the "warm-core" of a weak cyclone has a weak anticyclone in the center,whereas that of a strong cyclone has a weak cyclone in the center.(4)The "wet-core" of a tropical cyclone is primarily located in the lower level(700-850 hPa).With the cyclone's intensification,the intensity of the "wet-core" increases and the scope of the 0.8 g kg^(-1) specific humidity anomaly tends to expand to higher levels.(5) With the cyclone's deepening,the pseudo-equivalent potential temperature at different levels in different regions increases.In addition,the largest warming rates at each intensity level in the different regions occur in the core area,followed in turn by the envelope and outer areas. 展开更多
关键词 TROPICAL CYCLONES asymmetrical structure warm-core wet-core INTENSITY
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Stable single longitudinal mode erbium-doped silica fiber laser based on an asymmetric linear three-cavity structure 被引量:2
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作者 冯亭 延凤平 +4 位作者 李琦 彭万敬 冯素春 谭思宇 温晓东 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期268-272,共5页
We present a stable linear-cavity single longitudinal mode (SLM) erbium-doped silica fiber laser. It consists of four fiber Bragg gratings (FBGs) directly written in a section of photosensitive erbium-doped fiber ... We present a stable linear-cavity single longitudinal mode (SLM) erbium-doped silica fiber laser. It consists of four fiber Bragg gratings (FBGs) directly written in a section of photosensitive erbium-doped fiber (EDF) to form an asymmetric three-cavity structure. The stable SLM operation at a wavelength of 1545.112 nm with a 3-dB bandwidth of 0.012 nm and an optical signal-to-noise ratio (OSNR) of about 60 dB is verified experimentally. Under laboratory conditions, the performance of a power fluctuation of less than 0.05 dB observed from the power meter for 6 h and a wavelength variation of less than 0.01 nm obtained from the optical spectrum analyzer (OSA) for about 1.5 h are demonstrated. The gain fiber length is no longer limited to only several centimeters for SLM operation because of the excellent mode-selecting ability of the asymmetric three-cavity structure. The proposed scheme provides a simple and cost-effective approach to realizing a stable SLM fiber laser. 展开更多
关键词 asymmetric three-cavity structure single longitudinal mode erbium-doped fiber laser linear cavity
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AN ANALYSIS OF THE ASYMMETRICAL STRUCTURE OF TYPHOON AERE'S PRECIPITATION 被引量:2
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作者 濮江平 吕梅 邹力 《Journal of Tropical Meteorology》 SCIE 2010年第1期91-95,共5页
The structural characteristics of 2004 typhoon Aere's precipitation are analyzed using the high-resolution data from the Tropical Rainfall Measuring Mission(TRMM) of the National Aeronautics Space Administration(N... The structural characteristics of 2004 typhoon Aere's precipitation are analyzed using the high-resolution data from the Tropical Rainfall Measuring Mission(TRMM) of the National Aeronautics Space Administration(NASA).It is found that the typhoon's characteristics vary at different stages of its development.To analyze the asymmetric causation of precipitation distribution,data from the National Center for Environmental Prediction(NCEP) reanalysis are used to calculate the vertical integral of the water vapor flux vector.The results show that because of this process,along with the unique phenomenon of twin-typhoon circulation,the easterly air current of the typhoon's northern side and the southwesterly air current of its southern side play a joint role in transporting water vapor.Furthermore,its transport effects vary greatly at the different stages of development,showing the peculiarity of the water source for this typhoon process.The distributions of the typhoon convection area—characterized by heavy precipitation and a maximum-value area of the water vapor flux,as well as a strong ascending-motion area—differ at different stages of the typhoon's development.The non-uniform distribution of water vapor flux and the vertical motion bring about asymmetrical distribution of the typhoon precipitation. 展开更多
关键词 typhoon precipitation TRMM vapor flux vector asymmetrical structure
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Bcklund Transformation and Localized Coherent Structure for the (2+1)-Dimensional Asymmetric Nizhnik-Novikov-Veselov Equation 被引量:1
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作者 张解放 刘宇陆 《Journal of Shanghai University(English Edition)》 CAS 2002年第3期191-195,共5页
This article is concerned with the extended homogeneous balance method for studying the abundant localized solution structure of the (2+1) dimensional asymmetric Nizhnik Novikov Veselov equation. A B a¨... This article is concerned with the extended homogeneous balance method for studying the abundant localized solution structure of the (2+1) dimensional asymmetric Nizhnik Novikov Veselov equation. A B a¨ cklund transformation was first obtained, and then the richness of the localized coherent structures was found, which was caused by the entrance of two variable separated arbitrary functions, in the model. For some special choices of the arbitrary functions, it is shown that the localized structures of the model may be dromions, lumps, and ring solitons. 展开更多
关键词 homogeneous balance method coherent soliton structures asymmetric Nizhnik Novikov veselov equation (ANNV equation) B cklund transformation.
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Seismic Responses of Asymmetric Base-Isolated Structures under Near-Fault Ground Motion 被引量:1
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作者 叶昆 李黎 方秦汉 《Journal of Southwest Jiaotong University(English Edition)》 2008年第4期335-345,共11页
An inter-story shear model of asymmetric base-isolated structures incorporating deformation of each isolation bearing was built, and a method to simultaneously simulate bi-directional near-fault and far-field ground m... An inter-story shear model of asymmetric base-isolated structures incorporating deformation of each isolation bearing was built, and a method to simultaneously simulate bi-directional near-fault and far-field ground motions was proposed. A comparative study on the dynamic responses of asymmetric base-isolated structures under near-fault and far-field ground motions were conducted to investigate the effects of eccentricity in the isolation system and in the superstructures, the ratio of the uncoupled torsional to lateral frequency of the superstructure and the pulse period of near-fault ground motions on the nonlinear seismic response of asymmetric base-isolated structures. Numerical results show that eccentricity in the isolation system makes asymmetric base-isolated structure more sensitive to near-fault ground motions, and the pulse period of near-fault ground motions plays an import role in governing the seismic responses of asymmetric base-isolated structures. 展开更多
关键词 asymmetric base-isolated structure Near-fault ground motion Far-field ground motion Nonlinear seismic response
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Asymmetric structure of atomic above-threshold ionization spectrum in two-color elliptically polarized laser fields
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作者 Xu-Cong Zhou Shang Shi +4 位作者 Fei Li Yu-Jun Yang Jing Chen Qing-Tian Meng Bing-Bing Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期183-191,共9页
According to the frequency-domain theory, we investigate the asymmetric structure of above-threshold ionization(ATI) spectrum of an atom in two-color elliptically polarized(EP) laser fields. When both laser fields are... According to the frequency-domain theory, we investigate the asymmetric structure of above-threshold ionization(ATI) spectrum of an atom in two-color elliptically polarized(EP) laser fields. When both laser fields are linearly polarized(LP), the spectrum shows that the multi-plateau structure is symmetric about the emitted angle of electron at π/2, while the spectrum becomes asymmetric and shifts rightwards with the increase of the EP degree of the IR laser field. Since the total ATI process is regarded as including direct ATI and the rescattering ATI, we analyze the spectrum structure of direct ATI and rescattering ATI separately. Using the saddle-point approximation, we find that for direct ATI, the fringes on the spectrum are mainly attributed to the fact that the ionization probability becomes very small when the direction of emitted electrons is perpendicular to the direction of the XUV laser polarization;while for the rescattering ATI, the interference fringes on the spectrum mainly come from the superposition of the waist structures on the spectra of all sub-channels. 展开更多
关键词 ABOVE-THRESHOLD IONIZATION elliptically POLARIZED two color laser FIELDS asymmetric structure
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NUMERICAL EXPERIMENTS OF THE INFLUENCE OF DIABATIC HEATING ON TROPICAL CYCLONE ASYMMETRIC STRUCTURE
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作者 雷小途 《Journal of Tropical Meteorology》 SCIE 1998年第2期131-140,共10页
Using the barotropic volticity equation that contains forcing from diabatic heating with appropriate parameterization. a number of numerical experiments are conducted for the tropical cyclone that is initially symmetr... Using the barotropic volticity equation that contains forcing from diabatic heating with appropriate parameterization. a number of numerical experiments are conducted for the tropical cyclone that is initially symmetric The result shows that the diabatic heating has important effects on the asymmetric structure in addition to the roll of the β term and nonlinear advection term in its formation. It again confirms the conclusion that the diabatic heating is a possible mechanism responsible for such structures in the tropical cyclone. 展开更多
关键词 TROPICAL CYCLONE asymmetric structure diabatic HEATING
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A NUMERICAL ANALYSIS ON TYPHOON ASYMMETRIC STRUCTUREAND MOTION
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作者 袁金南 王国民 《Journal of Tropical Meteorology》 SCIE 1997年第2期159-167,共9页
Five prediction experiments are carried out with two typhoons in 1992 using a limited -arca primitiveequations and two-way interactive model in a movable ,nested mesh. The result indicates good agreementin terms of mo... Five prediction experiments are carried out with two typhoons in 1992 using a limited -arca primitiveequations and two-way interactive model in a movable ,nested mesh. The result indicates good agreementin terms of motion between the prediction and observation. Studying the asymmetric structure in the cas-es selected, a close link is uncovered between the temporal evolutions of the structure and the track of motion in a tropical cyclone. Understanding of real asymmetric structure will help to improve the skill offorecasting tropical cyclones. 展开更多
关键词 TYPHOON asymmetric structure TYPHOON TRACK of MOTION nested MESH model
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Effect of the asymmetric geometry on the wake structures of a pitching foil
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作者 LiMing Chao Guang Pan Dong Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第11期289-293,共5页
The two-dimensional wake produced by a time-periodic pitching foil with the asymmetric geometry is investigated in the present work. Through numerically solving nonlinear Navier–Stokes equations, we discuss the relat... The two-dimensional wake produced by a time-periodic pitching foil with the asymmetric geometry is investigated in the present work. Through numerically solving nonlinear Navier–Stokes equations, we discuss the relationship among the kinematics of the prescribed motion, the asymmetric parameter K ranged as-1 ≤ K ≤ 1, and the types of the wakes including the mP+nS wake, the B′enard–von K′arm′an wake, the reverse B′enard–von K′arm′an wake, and the deviated wake.Compared with previous studies, we reveal that the asymmetric geometry of a pitching foil directly affects the foil's wake structures. The numerical results show that the reverse B′enard–von K′arm′an wake is easily deviated at K 〈 0, while the symmetry-breaking of the reverse B′enard–von K′arm′an wake is delayed at K 〉 0. Through the vortex dynamic method,we understand that the initial velocity of the vortex affected by the foil's asymmetry plays a key role in the deviation of the reverse B′enard–von K′arm′an wake. Moreover, we provide a theoretical model to predict the wake deviation of the asymmetric foil. 展开更多
关键词 wake structures asymmetric geometry pitching foil
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Synthesis and Crystal Structure of (R)-4-Hydroxymethyl-2-thioxo Thiazolidine and Its Asymmetric Catalysis
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作者 LI Jing SHANG Yan-mei +3 位作者 XIAO Chuan SONG Zhi-guang LI Ye-zhi HUANG Hua-min 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第1期43-46,共4页
(R)-4-Hydroxymethyl-2-thioxo thiazolidine as a new chiral catalyst in the asymmetric addition of diethylzinc to benzaldehyde was synthesized from (R)-4-hydroxymethyl-2-thioxo thiazolidine carboxylic acid and its c... (R)-4-Hydroxymethyl-2-thioxo thiazolidine as a new chiral catalyst in the asymmetric addition of diethylzinc to benzaldehyde was synthesized from (R)-4-hydroxymethyl-2-thioxo thiazolidine carboxylic acid and its crystal structure was determined by X-ray diffraction method. The compound was crystallized in the orthorhombic system, space group P212121 with unit cell dimensions a=0.67253(12) nm; b=0.89164(17) nm; c=1.06146(19) nm, volume 0.6365(2) nm^3; Z=4, calculated denisity 1.557 Mg/m^3; absorption coefficient 0.733 mm^-1; F(000)=312. The X-ray crystal structure analysis reveals that the compound has a thione group. 展开更多
关键词 Crystal structure asymmetric (R)-4-Hydroxymethyl-2-thioxothiazolidine
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The role of viscoelastic damping on retrofitting seismic performance of asymmetric reinforced concrete structures
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作者 Zeshan Alam Chunwei Zhang Bijan Samali 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第1期223-237,共15页
The primary purpose of this research is to improve the seismic response of a complex asymmetric tall structure using viscoelastic(VE) dampers. Asymmetric structures have detrimental effects on the seismic performance ... The primary purpose of this research is to improve the seismic response of a complex asymmetric tall structure using viscoelastic(VE) dampers. Asymmetric structures have detrimental effects on the seismic performance because such structures create abrupt changes in the stiffness or strength that may lead to undesirable stress concentrations at weak locations. Structural control devices are one of the effective ways to reduce seismic impacts, particularly in asymmetric structures. For passive vibration control of structures, VE dampers are considered among the most preferred devices for energy dissipation. Therefore, in this research, VE dampers are implemented at strategic locations in a realistic case study structure to increase the level of distributed damping without occupying significant architectural space and reducing earthquake vibrations in terms of story displacements(drifts) and other design forces. It has been concluded that the seismic response of the considered structure retrofitted with supplemental VE dampers corresponded well in controlling the displacement demands. Moreover, it has been demonstrated that seismic response in terms of interstory drifts was effectively mitigated with supplemental damping when added up to a certain level. Exceeding the supplemental damping from this level did not contribute to additional mitigation of the seismic response of the considered structure. In addition, it was found that the supplemental damping increased the total acceleration of the considered structure at all floor levels, which indicates that for irregular tall structures of this type, VE dampers were only a good retrofitting measure for earthquake induced interstory deformations and their use may not be suitable for acceleration sensitive structures. Overall, the research findings demonstrate how seismic hazards to these types of structures can be reduced by introducing additional damping into the structure. 展开更多
关键词 viscoelastic dampers seismic analysis asymmetric structure nonlinear modal time history analysis
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SYNTHESIS AND STRUCTURE OF AN ASYMMETRIC TRICOBALT COMPOUND Co_3(o-HOC_6H_4S)_2(o-OC_6H_4S)_2(PEt_3)_3
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作者 Yong Jin XU Bei Sheng KANG Xue Tai CHEN Yong Han HU Fujian Institute of Research on the Structure of Matter and Fuzhou Laboratory of Structural Chemistry Chinese Academy of Science,Fuzhou,Fujian 350002 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第12期1017-1018,共2页
Compound Co_3(o-HOC_6H_4S)_2(o-OC_6H_4S)_2(PEt_3)_3 was obtained by reaction of CoCl_2, o-HOC_6H_4SH(H_2mD)and PEt_3 in ethanol in the presence of NaOCH_3.The three Co atoms are triangularly arranged and asymmetricall... Compound Co_3(o-HOC_6H_4S)_2(o-OC_6H_4S)_2(PEt_3)_3 was obtained by reaction of CoCl_2, o-HOC_6H_4SH(H_2mD)and PEt_3 in ethanol in the presence of NaOCH_3.The three Co atoms are triangularly arranged and asymmetrically bridged by four S and one O atoms from the four H_2mp ligands and terminally ligated by one O and three P atoms.Two free hydroxyl groups form two internal hydrogen bonds with adjacent oxo donor atoms. 展开更多
关键词 Co PEt3 SYNTHESIS AND structure OF AN asymmetric TRICOBALT COMPOUND Co3 o-HOC6H4S o-OC6H4S OC
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Asymmetric N,O-Coordinated Single Atomic Co Sites for Stable Lithium Metal Anodes
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作者 Yifan Li Daliang Fang +8 位作者 Xue Liang Li Dong Yan Shibo Xi Tian Chen Li Congjian Lin Shaozhuan Huang Jianbei Qiu Xuhui Xu Hui Ying Yang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第5期425-431,共7页
Lithium metal has been considered one of the most promising anodes for next-generation rechargeable batteries,but its practical application is largely hindered by the uncontrollable dendrite growth and infinite volume... Lithium metal has been considered one of the most promising anodes for next-generation rechargeable batteries,but its practical application is largely hindered by the uncontrollable dendrite growth and infinite volume change.Here,inspired by superior catalytic effects of single-atom catalysts,carbon-supported single atomic Co with asymmetric N,O-coordination(Co-N/O)is developed for Li metal battery.Experimental results and theoretical calculations indicate that single atomic Co atoms with asymmetric N,O-coordination present enhanced binding ability toward Li in comparison with N-coordinated atomic Co site and isolated O site,enabling uniform Li plating/stripping.Moreover,the asymmetric N,O-coordination around Co atoms induces co-activation effects,lowering the energy barriers toward Li^(+)to Li^(0)conversion and largely promoting the deposition kinetics.When used as a Li deposition host,the Co-N/O achieves a high average coulombic efficiency of 98.6%at a current density of 1 mA cm^(-2)and a capacity of 2 mAh cm^(-2),long cycling life of 2000 h in symmetrical cells,and excellent rate performance(voltage hysteresis of 23 mV at 8 mA cm^(-2)).This work provides a comprehensive understanding of single atomic metals with asymmetric heteroatom coordination in the design of Li metal anode. 展开更多
关键词 asymmetric atomic structure lithiophilicity lithium metal anode N O-coordination single atomic Co
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Unidirectional transport of both wettable and nonwettable liquids on an asymmetrically concave structured surface
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作者 Zhongxue Tang Kang Luan +1 位作者 Bojie Xu Huan Liu 《Fundamental Research》 CAS CSCD 2024年第3期557-562,共6页
Unidirectional liquid transport(UDLT)has been widely used in various fields as an important process for transferring both mass and energy.However,UDLT driven by a structural gradient has been witnessed for a long time... Unidirectional liquid transport(UDLT)has been widely used in various fields as an important process for transferring both mass and energy.However,UDLT driven by a structural gradient has been witnessed for a long time only in wettable liquids.For nonwettable liquids,UDLT can hardly proceed merely by a structural gradient.Herein,we propose an asymmetrically concave structured surface(AMC-surface),featuring tip-to-base periodically arranged pyramid-shaped concave structures with a certain degree of overlap,which enables the UDLT of both wettable and nonwettable liquids.For wettable liquids,the capillary force along each corner leads to the UDLT pointing toward the base side of the concave pyramid,while for nonwettable liquids,the UDLT is attributable to the static liquid pressure overwhelming the repulsive Laplace pressure induced by the asymmetric grooves and overlapping part.As a result,both wettable and nonwettable liquids transport spontaneously and unidirectionally on the AMC-surface with no energy input.Moreover,the concave structure endows good mechanical stability and can be easily prepared using a facile nail-punching approach over a large area.We also demonstrated its application in a continuous chemical reaction in a confined area.We envision that the unique UDLT behavior on the as-developed AMC-surface will shed new light on the programmable manipulation of various liquids. 展开更多
关键词 Unidirectional liquidtransport asymmetrically concave structure Capillary force Laplace pressure WETTABILITY
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Asymmetric Price Transmission and Structural Breaks in the Relationship between Costa Rican Markets of Livestock Cattle, Beef and Milk
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作者 K. Hernandez-Villafuerte 《Journal of Agricultural Science and Technology》 2010年第5期37-50,共14页
The vertical price transmission is generally considered as the relationship between two markets of the same production chain However, we can expand this concept to another relation which has not been deeply investiga... The vertical price transmission is generally considered as the relationship between two markets of the same production chain However, we can expand this concept to another relation which has not been deeply investigated: the joint products. They are the products which are produced in a single production process, but not correspond to the same chain. An especial case is the beef and milk markets in Costa Rica. Even if these products usually correspond to disconnect chains, in Costa Rica farms make use of cattle to produce both meat and milk. The cointegration framework is applied in order to indentify the price transmission among these markets. In addition, the asymmetric behavior and structural breaks are taken into account. Price transmission between each market pair was found. First, the cattle prices adjust in the milk-cattle relationship, second, beef meat prices adjust in the cattle-beef meat and in the milk - beef meat relationship. Finally, the equations allowing for structural breaks affect the estimates in the following three ways: after the break the elasticities became higher than 1, there is more evidence of cointegration, and the adjustment coefficients are significant only when a change in the long run is allowed. 展开更多
关键词 Vertical price transmission asymmetric prices transmission structural break LIVESTOCK BEEF MILK Costa Rica.
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Asymmetric reversible structural switching of a diene coordination polymer promoted by UV-visible light
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作者 Yong Wang Qiaoqiao Zhang +3 位作者 Yong-Yong Cao Qi Liu Brendan F.Abrahams Jian-Ping Lang 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第2期536-541,共6页
In natural and artificial systems,reversible reactions are commonly asymmetric with respect to the time scale and nature of the stimuli which drive the forward and backward processes.In applications for which switchin... In natural and artificial systems,reversible reactions are commonly asymmetric with respect to the time scale and nature of the stimuli which drive the forward and backward processes.In applications for which switching behavior is required,it is desirable that the reversible reaction goes as close to symmetric as possible;however,such systems are uncommon.Herein,we report an example of ultraviolet(UV)-visible light-regulated asymmetric reversible structural switching involving a diene-based coordination polymer,CP1 and its monocyclobutane product,CP1a.It is possible to cycle at least ten times through a forward [2+2] photocycloaddition reaction and the reverse,photocleavage reaction.A single cycle can be completed within a few minutes.The transformation is accompanied by fast and distinct fluorescence changes,arising from optimisation of the reaction conditions.Density functional theory calculations allow rationalisation of the asymmetric reversible transformation between CP1 and CP1a rather than between CP1 and its dicyclobutane product CP1b.This work provides a clear illustration of reversible structural switching which approaches symmetric behaviour with respect to reaction rate and stimuli.The insights gained from this work also assist in the design of fast,reversible switching materials. 展开更多
关键词 asymmetrical reversible structural switching coordination polymer PHOTOCYCLOADDITION UV-visible light-controlled fluorescence switching
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Recent Advances in Asymmetric Structural Composites for Excellent Electromagnetic Interference Shielding:A Review
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作者 Ying Zhou Bai Xue +2 位作者 Lan Xie Chang-Mei Wu Qiang Zheng 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第6期693-710,共18页
Since electromagnetic pollution is detrimental to human health and the environment,numerous efforts have been successively made to achieve excellent electromagnetic interference shielding effectiveness(EMI SE)via desi... Since electromagnetic pollution is detrimental to human health and the environment,numerous efforts have been successively made to achieve excellent electromagnetic interference shielding effectiveness(EMI SE)via designing the hierarchical structures for electromagnetic interference(EMI)shielding polymer composites.Among the plentiful structures,the asymmetric structures are currently a hot spot,principally categorizing into multi-layered,porous,fibrous,and segregated asymmetric structures,which endows the high EMI shielding performance for polymer composites incorporated with magnetic,conductive,and/or dielectric micro/nano-fillers,due to the“absorption-reflection-reabsorption”shielding mechanism.Therefore,this review provides the retrospection and summary of the efforts with respect to abundant asymmetric structures and multifunctional micro/nano-fillers for enhancing EMI shielding properties,which is conducive to the booming development of polymeric EMI shielding materials for the promising prospect in modern electronics and 5-generation(5G)technology. 展开更多
关键词 asymmetric structure Micro/nano functional fller Polymer composite Electromagnetic interference shielding
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Asymmetric Regulation System Fit for Chinese Telecom Market 被引量:2
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作者 Shi Wei Zhao Xuefeng Ma Conghui 《China Communications》 SCIE CSCD 2008年第3期99-103,共5页
After the new round of restructuring of Chinese telecom sector,it's pressing to formulate and implement asymmetric regulation policies so as to shape an effectively competitive market structure in a relatively sho... After the new round of restructuring of Chinese telecom sector,it's pressing to formulate and implement asymmetric regulation policies so as to shape an effectively competitive market structure in a relatively short term.This paper reviewed the asymmetric regulation policies and practices carried out in foreign telecom market,and then according to the specific situations of Chinese telecom market,proposed the principles and corresponding policies for establishing an asymmetric regulation system fit for Chinese telecom market. 展开更多
关键词 telecommunications MARKET structure asymmetry asymmetric REGULATION EFFECTIVE REGULATION
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