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有机果蔬自料饮品店的实施研究
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作者 文德萍 尹璐 《现代商业》 2016年第20期16-17,共2页
我国经济高速发展的同时,出现了一些严重的食品危机事件。饮品作为餐饮重要的一部分,消费者对其质量的要求也越来越高。有机果蔬自料饮品店正是基于对健康的考虑,为我们的生活提供了一种新型的饮品消费方式。文章主要从有机果蔬自料饮... 我国经济高速发展的同时,出现了一些严重的食品危机事件。饮品作为餐饮重要的一部分,消费者对其质量的要求也越来越高。有机果蔬自料饮品店正是基于对健康的考虑,为我们的生活提供了一种新型的饮品消费方式。文章主要从有机果蔬自料饮品店的特点、形式、市场潜力、发展中可能出现的风险以及应对策略等方面分析了有机果蔬自料饮品店存在与发展的可行性。 展开更多
关键词 绿色健康 有机果蔬 自料饮品 体验性消费 营养愉悦
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The effect of the carbon components on the performance of carbonbased transition metal electrocatalysts for the hydrogen evolution reaction
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作者 LI Guo-hua WANG Jing +6 位作者 REN Jin-tian LIU Hong-chen QIAN Jin-xiu CHENG Jia-ting ZHAO Mei-tong YANG Fan LI Yong-feng 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期946-972,共27页
The hydrogen evolution reaction(HER)is a promising way to produce hydrogen,and the use of non-precious metals with an excellent electrochemical performance is vital for this.Carbon-based transition metal catalysts hav... The hydrogen evolution reaction(HER)is a promising way to produce hydrogen,and the use of non-precious metals with an excellent electrochemical performance is vital for this.Carbon-based transition metal catalysts have high activity and stability,which are important in reducing the cost of hydrogen production and promoting the development of the hydrogen production industry.However,there is a lack of discussion regarding the effect of carbon components on the performance of these electrocatalysts.This review of the literature discusses the choice of the carbon components in these catalysts and their impact on catalytic performance,including electronic structure control by heteroatom doping,morphology adjustment,and the influence of self-supporting materials.It not only analyzes the progress in HER,but also provides guidance for synthesizing high-performance carbon-based transition metal catalysts. 展开更多
关键词 Carbon-based transition metal catalysts Heteroatom doping Morphology adjustment Self-supporting materials Hydrogen evolution reaction
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高蛋白料精等量替代豆粕对早期断奶仔猪增重的影响
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作者 雷风 《黑龙江畜牧兽医》 CAS 北大核心 2004年第5期34-34,共1页
关键词 高蛋自料 豆粕 早期断奶 仔猪 增重 日粮
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Microstructure and evolution of(TiB_2+Al_2O_3)/NiAl composites prepared by self-propagation high-temperature synthesis 被引量:3
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作者 宋晓杰 崔洪芝 +1 位作者 曹丽丽 P.Y.GULYAEV 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1878-1884,共7页
(TiB2+Al2O3)/NiAl composites were synthesized by self-propagation high-temperature synthesis, and their phase compositions, microstructures and evolution modes were studied. The microstructures and shapes vary with... (TiB2+Al2O3)/NiAl composites were synthesized by self-propagation high-temperature synthesis, and their phase compositions, microstructures and evolution modes were studied. The microstructures and shapes vary with the TiB2+Al2O3 content in the NiAl matrix. TiB2 particles take a great variety of elementary shapes such as white bars, plates, herringbones, regular cubes and cuboids. These results outline a strategy of self-assembly processes in real time to build diversified microstructures. Some TiB2 grains in sizes of 2-5μm are embeded in Al2O3 clusters, while a small number of TiB2 particles disperse in the NiAl matrix. It is believed that the higher the TiB2+Al2O3 content is, the more the regular shapes and homogeneous distributions of TiB2 and Al2O3 will be present in the NiAl matrix. 展开更多
关键词 (TiB2+Al2O3)/NiAl composites self-propagation high-temperature synthesis MICROSTRUCTURE evolution mechanism
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Effects of temperature on fracture behavior of Al-based in-situ composites reinforced with Mg_2Si and Si particles fabricated by centrifugal casting 被引量:5
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作者 李波 王开 +3 位作者 刘明翔 薛寒松 朱子宗 刘昌明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期923-930,共8页
An aluminum-based in-situ composites reinforced with Mg2Si and Si particles were produced by centrifugal casting A1-20Si-5Mg alloy. The microstructure of the composites was examined, and the effects of temperature on ... An aluminum-based in-situ composites reinforced with Mg2Si and Si particles were produced by centrifugal casting A1-20Si-5Mg alloy. The microstructure of the composites was examined, and the effects of temperature on fracture behavior of the composite were investigated. The results show that the average fraction of primary Si and Mg2Si particles in the composites is as high as 38%, and ultimate tensile strengths (UTS) of the composites first increase then decrease with the increase of test temperature. Microstructures of broken specimens show that both the particle fracture and the interface debonding affect the fracture behavior of the composites, and the interface debonding becomes the dominant fracture mechanism with increasing test temperature. Comparative results indicate that rich particles in the composites and excellent interface strength play great roles in enhancing tensile property by preventing the movement of dislocations. 展开更多
关键词 aluminum based in-situ composites fracture behavior centrifugal casting high temperature
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Identification of the Parentage of Corn Variety Using SSR Markers 被引量:11
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作者 沈童伟 陆徐忠 +2 位作者 刘勋辉 李莉 杨剑波 《Agricultural Science & Technology》 CAS 2009年第4期55-60,共6页
[Objective] The study was to explore the molecular interpretation standards on parentage in the seeds of corn variety. [Method] With 16 hybrids and their parents and 202 inbred elites as materials for screening primer... [Objective] The study was to explore the molecular interpretation standards on parentage in the seeds of corn variety. [Method] With 16 hybrids and their parents and 202 inbred elites as materials for screening primers, the artificial groups of two standard diad and two standard triad were respectively established as the verification materials. Genomic DNA of seedlings was extracted by using CTAB method. 137 pairs of SSR primers were selected for SSR amplification and product detection, which was used for the parentage identification of maize varieties. [ Result] Twenty pairs of corn primers with high polymorphism information content ( PIC value), clearly amplified bands and good reproducibility were screened from 137 pairs of corn SSR primers tested. The identification results of using SSR molecular were consistent with the actual situation. [ Conclusion] It is feasible to identify the parentage of maize variety using SSR markers. 展开更多
关键词 MAIZE SSR marker Corn primer Parentage identification
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民国时期福建纸的生产与运销
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作者 林仁川 《中国社会经济史研究》 CSSCI 北大核心 1989年第1期78-86,共9页
本省山地竹林密布,造纸原料丰富,出产纸品十分繁杂,据不完全统计,全省纸类达二百余种以上,其中比较著名的有七、八十种,若按用途归类,大概可分为四大种: (一) 白料纸类: 此类纸选料较精,加工较细,质量较好,“白料制时曾用碱水蒸煮数遍... 本省山地竹林密布,造纸原料丰富,出产纸品十分繁杂,据不完全统计,全省纸类达二百余种以上,其中比较著名的有七、八十种,若按用途归类,大概可分为四大种: (一) 白料纸类: 此类纸选料较精,加工较细,质量较好,“白料制时曾用碱水蒸煮数遍、藉天然水力漂洗清净,永不变色变质耳”。主要用于书写,在海关输出上称为上等纸。本省白料上等纸的主要种类有:顺太、毛太、毛边、白宫、毛六、晾纸、白纸、毛纸、全料、大扣、代白、毛八、连史、连三、大广、贡纸、双料、料米、老筐、放匡、小切、官堆、京庄、香皮。 展开更多
关键词 纸类 纸行 纸的生产 庄客 中心市场 民国时期 汀江流域 中级市场 自料 海关
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Wear behavior of SiC/PyC composite materials prepared by electromagnetic-field-assisted CVI 被引量:1
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作者 涂川俊 黄启忠 +3 位作者 熊贤至 谢志勇 蔡利辉 陈珊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期856-862,共7页
Silicon carbide/pyrolytic carbon (SiC/PyC) composite materials with excellent performance of self-lubrication and wear resistance were prepared on SiC substrates by electromagnetic-field-assisted chemical vapor infilt... Silicon carbide/pyrolytic carbon (SiC/PyC) composite materials with excellent performance of self-lubrication and wear resistance were prepared on SiC substrates by electromagnetic-field-assisted chemical vapor infiltration (CVI). The composition and microstructure of the SiC/PyC materials were investigated in detail by XRD, SEM and EDS, etc. The effects of the deposition temperature on the section features and wear resistance of the SiC/PyC were studied. The results show that the PyC layers were deposited onto SiC substrates spontaneously at a lower deposition temperature. The SiC substrates deposited with PyC can significantly reduce the wear rate of the self-dual composite materials under dry sliding condition. The wear tests suggest that the SiC/PyC composite materials own a better wear resistance property when the deposition temperature is 800 °C, and the wear rate is about 64.6% of that without the deposition of PyC. 展开更多
关键词 SiC/PyC composite materials wear performance SELF-LUBRICATING chemical vapor infiltration interfacial adsorption
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高标逸韵冰雪中——《梅花绝句(其二)》赏读
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作者 张英华 《作文(初中年级)》 2019年第1期55-55,共1页
原文梅花绝句(其二)陆游幽谷那堪更北枝(1),年年自分著花迟(2)。高标逸韵君知否?正是层冰积雪时。注释(1)那:古通'哪'。(2)自分:自料。阐发幽深的山谷,峭壁陡立,如高墙一般,总想将阳光拦在谷外。太阳只有走到山谷上方的时候,才... 原文梅花绝句(其二)陆游幽谷那堪更北枝(1),年年自分著花迟(2)。高标逸韵君知否?正是层冰积雪时。注释(1)那:古通'哪'。(2)自分:自料。阐发幽深的山谷,峭壁陡立,如高墙一般,总想将阳光拦在谷外。太阳只有走到山谷上方的时候,才能将一缕缕温暖的光芒送进山谷。 展开更多
关键词 峭壁 高墙 自料 高标 山谷 幽谷 北枝 陆游
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证件遗失 声明作废
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《交通与运输》 1998年第4期47-47,共1页
关键词 证件 南货 营运证 运输 水货 侧刃 自料 伪书 止口 书目
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赋得暮雨送李曹
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作者 韦应物 雅婷 《语文世界(上旬刊)》 2000年第2期13-13,共1页
关键词 韦应物 建业 各具特色 长江 叠字 散丝 王勃 诗眼 自料 初唐
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心存爱意
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作者 孙景 《河南教育(基教版)(上)》 1998年第4期37-37,共1页
心存爱意●孙景遭遇不幸时,我们渴望温馨的抚慰;为恶语中伤时,我们呼唤善良的回归;被误解时,我们希望理解;遭歧视时,我们企求平等……我们希望这世界美好,我们愿和谐的风将烦恼的云吹散,人人都成为童话里的好人,人人都有一个... 心存爱意●孙景遭遇不幸时,我们渴望温馨的抚慰;为恶语中伤时,我们呼唤善良的回归;被误解时,我们希望理解;遭歧视时,我们企求平等……我们希望这世界美好,我们愿和谐的风将烦恼的云吹散,人人都成为童话里的好人,人人都有一个瑰丽的梦想。而梦想成真的办法只有一... 展开更多
关键词 遭遇不幸 人人都 爱意 涌现出 叶子 童话 自料 叶相 心照 伤时
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Climatic Conditions of Regional Distribution of Characteristic Agriculture——With West Celery Industrial Belt in Huluhe Basin as an Example
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作者 孙俊 《Agricultural Science & Technology》 CAS 2012年第12期2598-2602,2654,共6页
[Objective] The paper was to study the climate conditions of celery indus- trial belt in Huluhe Basin. [Method] Using the climate data of Xiji national basic sta- tion during 1981 and 2010, the meteorological data dur... [Objective] The paper was to study the climate conditions of celery indus- trial belt in Huluhe Basin. [Method] Using the climate data of Xiji national basic sta- tion during 1981 and 2010, the meteorological data during crop growth period in 3 automatic weather stations along Huluhe Basin were carried out regression analysis, and the climate condition of west celery industrial belt was conducted hierarchical clustering analysis by SPSS. [Result] West celery industrial belt along Huluhe Basin could be divided into 2 growing regions: partially southern warm, rainy and early mature region, partially northern cold, rainless and late mature region. Years of practice proved that the small climate differences within 2 planting regions were more obvious, so these 2 planting regions could be further divided into 4 subre- glens: Xinglong warm, rainy and early mature subregion, Xiaohe thermal, rainy and partially early mature region, Jiqiang cool, rainless and middle mature subregion and Xinying cold, rainless and late mature subregion. [Conclusion] The study has refer- ence value for determination of different sowing time, different fertilizer and irrigation scheme, pests and diseased control and marketing time of west celery under mulch- sanded bunch plantation in market economic condition. 展开更多
关键词 Automatic Station Data West celery industrial belt Climatic conditions Cluster analysis
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An Air-Breathing Micro Direct Methanol Fuel Cell with 3D KOH-Etched Cathode Structure
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作者 姜英琪 王晓红 +1 位作者 钟凌燕 刘理天 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第3期478-481,共4页
A micro direct methanol fuel cell (μDMFC) using MEMS technology is reported. The prototype features a unique 3D air-breathing cathode structure fabricated using KOH etching and double-side lithography. The optimiza... A micro direct methanol fuel cell (μDMFC) using MEMS technology is reported. The prototype features a unique 3D air-breathing cathode structure fabricated using KOH etching and double-side lithography. The optimization of the MEMS fabrication process is analyzed. The experimental results show the prototype generates a maximum power density of 2.52mW/cm^2 at room temperature. This performance is better than the published resuits of other silicon-based passive μDMFCs. Moreover,it is comparable with that of our previous active μDMFCs which require an external pump, certificating the feasibility of this new configuration. 展开更多
关键词 μDMFC air breathing bulk etching MEMS micro power source
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Effect of Ti-Al content on microstructure and mechanical properties of C_f/Al and TiAl joint by laser ignited self-propagating high-temperature synthesis 被引量:5
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作者 冯广杰 李卓然 +1 位作者 冯士诚 申忠科 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1468-1477,共10页
Cf/Al composites and TiAl alloys were joined by laser ignited self-propagating high-temperature synthesis(SHS) with Ni-Al-Ti interlayer. The effect of Ti-Al content on interfacial microstructure and mechanical prope... Cf/Al composites and TiAl alloys were joined by laser ignited self-propagating high-temperature synthesis(SHS) with Ni-Al-Ti interlayer. The effect of Ti-Al content on interfacial microstructure and mechanical properties of the joints was investigated. Localized melt of the substrates occurred in the joints. γ-Ni0.35Al0.30Ti0.35, NiA l3 and Ni2Al3 reaction layers formed adjacent to the substrates. Joint flaws, such as pores and cracks, made the joint density decrease and worked as the fracture source, which led to the sharp decline of joint strength. Additive Ti-Al increased joint density and strengthened the interlayer adhesion to Cf/Al. The joint flaws could be controlled by changing the Ti-Al content. When the Ti-Al content was 0.1, the joint was free of cracks with high density and reached the maximum shear strength of 24.12 MPa. 展开更多
关键词 Cf/Al composite TiAl alloys JOINT self-propagating high-temperature synthesis INTERLAYER Ti-Al content
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SYSTEM IDENTIFICATION OF ADAPTIVE TRUSS STRUCTURES USING PIEZOELECTRIC ACTIVE MEMBERS
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作者 李俊宝 刘华 张令弥 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第2期122-128,共7页
Adaptive truss structures are a new kind of structures with integrated active members,whose dynamic characteristies can be beneficially modified to meet mission requirements.Active members containing actuating and sen... Adaptive truss structures are a new kind of structures with integrated active members,whose dynamic characteristies can be beneficially modified to meet mission requirements.Active members containing actuating and sensing units are the major components of adaptive truss structures.Modeling of adaptive truss structures is a key step to analyze the structural dynamic characteristics.A new experimental modal analysis approach,in which active members are used as excitatiDn sources for modal test,has been proposed in this paper.The excitation forces generated by the active members, which are different from the excitation forces exerted on structures in the conventional modal test,are internal forces for the truss structures.The relation between internal excitation forces and external forces is revealed such that the traditional identification method can be adopted to obtain modal parameters of adaptive structures.Placement problem of the active member in adaptive truss structures is also discussed in this work. Modal test and analysis are conducted with a planar adaptive truss structure by using piezoelectric active members in order to verify the feasibility and effectiveness of the proposed method. 展开更多
关键词 systems identification vibrations piezoelectric materials active member adaptive truss structure modal test
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VIBRATION MODE ANALYSIS OF MULTILAYERED COMPOSITE PLATES AND SHELLS USING NATURAL APPROACH
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作者 朱金福 王永亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第2期114-121,共8页
Argyris'natural approach is employed to analyze vibranon mode of multilayered composite plates and shells.The shells can be either symmetric or unsymmetric.The spectral transformation Lanczos method with selective... Argyris'natural approach is employed to analyze vibranon mode of multilayered composite plates and shells.The shells can be either symmetric or unsymmetric.The spectral transformation Lanczos method with selective or fully orthogonalization is used to solve the eigenvalue problem of pencil(K,M).Some problems on shift,which is essential for the success of this method, are discussed.A few numerical examples, including composite square plates and conical shells,are presented. The results show that the method in this paper is efficient and reliable for vibration mode analysis. 展开更多
关键词 vibration analysis method composite materials PLATES Lanczos method natural approach
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Effects of superabsorbent polymer particles on flexural properties and self-healing behavior of ECC 被引量:5
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作者 Deng Hanwen 《Journal of Southeast University(English Edition)》 EI CAS 2018年第1期95-103,共9页
In order to improve the self-healing behavior and the recovery of mechanical properties of engineered cementitious composites(ECC),the approach of incorporating superabsorbent polymer(SAP)in mixtures is investigated.T... In order to improve the self-healing behavior and the recovery of mechanical properties of engineered cementitious composites(ECC),the approach of incorporating superabsorbent polymer(SAP)in mixtures is investigated.The rapid water penetration test and four-point bending test were conducted to evaluate the effects of self-healing on the water permeability and mechanical properties of pre-damaged ECC.The self-healing process and self-healing products were observed by the environment scanning electron microscope(ESEM)and energy dispersive X-ray spectroscopy(EDS).The experimental results show that all ECC mixtures exhibit excellent flexural capacity,meanwhile maintaining a crack width below 50μm.The incorporation of SAP particles in ECC can apparently improve the mechanical recovery of ECC mixtures after 10 healing curing cycles,such as flexural deformation and flexural stiffness.The flexural stiffness of ECC containing 4%SAP particles after self-healing can be recovered to 80%.The self-healing test results show that when the water permeability of ECC mixtures incorporating SAP particles is close to zero,only three healing cycles are needed.When ECC incorpora ting more SAP particles,the accelerated self-healing process can be finished in the first three cycles,and self-healing product is mixed Ca(OH)2/CaCO 3 with CaCO 3 being a major component in the later stage.It is,therefore,feasible to produce ECC materials incorporating SAP particles,while simultaneously maintaining higher material ductility and self-healing behavior. 展开更多
关键词 engineered cementitious composites(ECC) SELF-HEALING superabsorbent polymer(SAP) mechanical property
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Corrosion and discharge performance of Mg-9%Al-2.5%Pb alloy as anode for seawater activated battery 被引量:2
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作者 Min DENG Ri-chu WANG +2 位作者 Yan FENG Nai-guang WANG Lin-qian WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第8期2144-2151,共8页
To obtain a new kind of Mg?Al?Pb alloy anode material with low content of Pb, the corrosion and discharge behavior of Mg?9%Al?2.5%Pb (hereafter in mass fraction) alloy were investigated by immersion tests and electroc... To obtain a new kind of Mg?Al?Pb alloy anode material with low content of Pb, the corrosion and discharge behavior of Mg?9%Al?2.5%Pb (hereafter in mass fraction) alloy were investigated by immersion tests and electrochemical techniques, and compared with those of Mg?6%Al?5%Pb alloy. The results indicate that Mg?9%Al?2.5%Pb alloy exhibits a lower self-corrosion rate and higher utilization efficiency in contrast with Mg?6%Al?5%Pb alloy because of the higher content of Al. As the result of the decrease of Pb content, the discharge activity of Mg?9%Al?2.5%Pb alloy is relatively weaker but still meets the requirement of anode. These results reveal that Mg?9%Al?2.5%Pb alloy with a low content of Pb can serve as a good candidate for the anode material used in seawater activated battery. 展开更多
关键词 Mg.Al.Pb alloy anode material self-corrosion rate utilization efficiency discharge activity
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Multistable Mechanical Metamaterials:A Brief Review 被引量:3
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作者 ZHANG Hang WU Jun +1 位作者 ZHANG Yihui FANG Daining 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第1期1-17,共17页
Over the past decade,multistable mechanical metamaterials have been widely investigated because of their novel shape reconfigurability and programmable energy landscape.The ability to reversibly reshape among diverse ... Over the past decade,multistable mechanical metamaterials have been widely investigated because of their novel shape reconfigurability and programmable energy landscape.The ability to reversibly reshape among diverse stable states with different energy levels represents the most important feature of the multistable mechanical metamaterials.We summarize main design strategies of multistable mechanical metamaterials,including those based on self-assembly scheme,snap-through instability,structured mechanism and geometrical frustration,with a focus on the number and controllability of accessible stable states.Then we concentrate on unusual mechanical properties of these multistable mechanical metamaterials,and present their applications in a wide range of areas,including tunable electromagnetic devices,actuators,robotics,and mechanical logic gates.Finally,we discuss remaining challenges and open opportunities of designs and applications of multistable mechanical metamaterials. 展开更多
关键词 multistable mechanical metamaterials SELF-ASSEMBLY SNAP-THROUGH structured mechanism geometrical frustration
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