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Potential Applications of Nano-Scale Science and Technology in Geosciences and Experimental Studies of Nanometer-Sized Gold Adsorption on Minerals and Rocks 被引量:3
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作者 章振根 朱笑青 《Chinese Journal Of Geochemistry》 EI CAS 1997年第2期133-138,共6页
Potential applications of Nano-scale science and technology are discussed in mineralogy, ore deposits, cosmochemistry and environmental sciences. Adsorption of nanometersized gold was experimentally studied on a varie... Potential applications of Nano-scale science and technology are discussed in mineralogy, ore deposits, cosmochemistry and environmental sciences. Adsorption of nanometersized gold was experimentally studied on a variety of minerals and rocks. 展开更多
关键词 纳米技术 地球科学 地球化学 纳米金 吸收 矿物 岩石
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Numerical Analysis of the Adhesive Forces in Nano-Scale Structure 被引量:1
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作者 Young-Sam Cho Houkseop Han Wan-Doo Kim 《Journal of Bionic Engineering》 SCIE EI CSCD 2006年第4期209-216,共8页
Nanohairs, which can be found on the epidermis of Tokay gecko's toes, contribute to the adhesion by means of van der Waals force, capillary force, etc. This structure has inspired many researchers to fabricate the at... Nanohairs, which can be found on the epidermis of Tokay gecko's toes, contribute to the adhesion by means of van der Waals force, capillary force, etc. This structure has inspired many researchers to fabricate the attachable nano-scale structures. However, the efficiency of artificial nano-scale structures is not reliable sufficiently. Moreover, the mechanical parameters related to the nano-hair attachment are not yet revealed qualitatively. The mechanical parameters which have influence on the ability of adhesive nano-hairs were investigated through numerical simulation in which only van der Waals force was considered. For the numerical analysis, finite element method was utilized and van der Waals force, assumed as 12-6 Lennard-Jones potential, was implemented as the body force term in the finite element formulation. 展开更多
关键词 NUMERICAL analysis adhesive force nano-scale structure finite element model van der Waals force 12-6 L-J potential
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Aspects of Characterisation of Thin Coating Adhesion at the Nano-Scale
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作者 JishengE AiyangZhang 《材料导报》 EI CAS CSCD 2002年第7期5-10,共6页
In response to current development of materials in nano-science.characterisation of thin coating adhesion ona nano-scale becomes one of the most important research areas,as new coatings get ever thinner and more techn... In response to current development of materials in nano-science.characterisation of thin coating adhesion ona nano-scale becomes one of the most important research areas,as new coatings get ever thinner and more technologically advanced.With a review of technology and mechanisms of evaluating the adhesion failure of coatings.three techniques,nano-im-pact,nano-scratch and nano-indentation techniques,for charactering the adhesion of thin coatings on a nano scale are described.Results of charactering the adhesion faliure of thin coatings using three different techniques indicate that the nano scratch and nano-indentation techniques are very useful tools particularly in charactering the performance of thin coatings under nano-abra sive wear conditions.However,results from these types of tests cannot be easily applied to predict the performance of coatings whose are subject to nano-erosive wear,cyclic nano-fatigue or multiple nano-impacts during service.Instead,results of the new dynamic testing technique。 展开更多
关键词 薄膜 纳米尺度 结构 性质 特征
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Nano-scaled metal powder improving tribological properties of lubricant
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作者 万轶 熊党生 王恒志 《中国有色金属学会会刊:英文版》 CSCD 2005年第S3期167-170,共4页
Cu nanoparticles were fabricated by ball milling with the anhydrous alcohol as dispersant. The size and figure of Cu nanoparticles were characterized by X-ray diffractometry and transmission electron microscopy. The t... Cu nanoparticles were fabricated by ball milling with the anhydrous alcohol as dispersant. The size and figure of Cu nanoparticles were characterized by X-ray diffractometry and transmission electron microscopy. The tribological properties of adding Cu and MoS2 nanoparticles to the pure grease were measured on MM-200 tester, compared with the single additive and pure grease. The results show the size of Cu nanoparticles is about 50 nm. The surface with lubricant added nanopowder as additive possesses a remarkable decrease in wear volume. The friction coefficient and wear volume of lubricant mixed with 5% copper and 30% disulfide molybdenum nanoparticles are 0.09 and 1.80mm3, respectively. This mixed additive can not only increase the ability of supporting heavy load but repair the microscopic channels and cracks on the wear surface. Under higher load and long period of time, this lubricant has the characteristics of self-repairing, occluding resistance and ability of enduring higher temperature. 展开更多
关键词 nano-scaled metal POWDER BALL MILLING friction and WEAR properties
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Effect of Surface Roughness in Micro-nano Scale on Slotted Waveguide Arrays in Ku-band
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作者 Na LI Peng LI Liwei SONG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期595-603,共9页
Modeling of the roughness in micro-nano scale and its influence have not been fully investigated, however the roughness will cause amplitude and phase errors of the radiating slot, and decrease the precision and effic... Modeling of the roughness in micro-nano scale and its influence have not been fully investigated, however the roughness will cause amplitude and phase errors of the radiating slot, and decrease the precision and efficiency of the SWA in Ku-band. Firstly, the roughness is simulated using the electromechanical coupled(EC) model. The relationship between roughness and the antenna's radiation properties is obtained. For verification, an antenna proto- type is manufactured and tested, and the simulation method is introduced. According to the prototype, a contrasting experiment dealing with the flatness of the radiating plane is conducted to test the simulation method. The advantage of the EC model is validated by comparisons of the EC model and two classical roughness models (sine wave and fractal function), which shows that the EC model gives a more accurate description model for roughness, the maxi- mum error is 13%. The existence of roughness strongly broadens the beamwidth and raises the side-lobe level of SWA, which is 1.2 times greater than the ideal antenna. In addition, effect of the EC model's evaluation indices is investigated, the most affected scale of the roughness is found, which is 1/10 of the working wavelength. The proposed research provides the instruction for antenna designing and manufacturing. 展开更多
关键词 Slotted waveguide arrays - Roughness model Micro/nano-scale Amplitude and phase errors Radiationcharacteristics
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Nano-scale Interfacial Friction Behavior between Two Kinds of Materials in MEMS Based on Molecular Dynamics Simulations
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作者 杨平 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第4期173-176,共4页
The aim of this article was to provide a systematic method to perform molecular dynamics simulotion or evaluation for nano-scale interfacial friction behavior between two kinds of materials in MEMS design. Friction is... The aim of this article was to provide a systematic method to perform molecular dynamics simulotion or evaluation for nano-scale interfacial friction behavior between two kinds of materials in MEMS design. Friction is an important factor affecting the performance and reliability of MEMS. The model of the nano-scale interracial friction behavior between two kinds of materials was presented based on the Newton' s equations of motion. The Morse potential function was selected for the model. The improved Verlet algorithm was employed to resolve the model, the atom trajectories and the law of the interfacial friction behavior. Comparisons with experimental data in other paper confirm the validity of the model. Using the model it is possible to simulate or evaluate the importance of different factors for designing of the nano-scale interfacial friction behavior between two kinds of materials in MEMS. 展开更多
关键词 molecular dynamics simulation interfacial friction nano-scale friction MEMS
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Acheivement of Nano-Scale SiGe Layer with Discrete Ge Mole Fraction Profile Using Batch-Type HVCVD
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作者 Gon-sub Lee Tae-hun Shim Jea-gun Park 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第z2期178-182,共5页
The strained Si grown on the relaxed SiGe-on-insulator C-MOSFET's is a promising device for the future system LSI devices with the design rule of sub-micron. The achievement of the discrete Ge mole fraction in the... The strained Si grown on the relaxed SiGe-on-insulator C-MOSFET's is a promising device for the future system LSI devices with the design rule of sub-micron. The achievement of the discrete Ge mole fraction in the SiGe layer is a key engineering in low-temperature SiGe epitaxial growth using HVCVD. The pre-flow of GeH4 gas enhanced the Ge mole fraction and SiGe layer thickness. In addition, the Ge mole fraction and SiGe layer thickness increases with the gas ratio of GeH4/SiH4 + GeH4, process temperature, and gas flow time. However, the haze was produced if the Ge mole fraction is above 22wt%. The discrete-like Ge mole fraction with 22 wt% in 10 nm SiGe layer was obtained by the pre-flow of GeH4 for 10 s, the mixture gas ratio of GeH4/SiH4 + GeH4 of 67%, and the gas flow time for 150 s at the process temperature of 550 C. 展开更多
关键词 STRAINED Si nano scale SIGE LAYER Ge MOLE FRACTION HVCVD gas flow boat-out time
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Schrodinger-Langevin Equation and Ion Transport atNano Scale
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作者 Samyadeb Bhattacharya Suman Dutta Sisir Roy 《Journal of Modern Physics》 2011年第4期231-235,共5页
Schrodinger-Langevin equation has been constructed for the ion-transport for K-ion channel. The stability of the solutions of this equation has been discussed under various physical situations. This will shed new ligh... Schrodinger-Langevin equation has been constructed for the ion-transport for K-ion channel. The stability of the solutions of this equation has been discussed under various physical situations. This will shed new light on the ion transport at nano-scale as well as the possibility of ion trapping and quantum information processing. 展开更多
关键词 Schrodinger-Langevin EQUATION Stochastic MECHANICS LYAPUNOV Stability Ion Transport at nano scale
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Electronic Structure of Single-Crystal CaF<sub>2</sub>(111) with Nanoscale Phases of Ca and Si
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作者 Yokub Suvonovich Ergahov Boltakhodja Ermatovich Umirzakov Gulmira Khalmuratovna Allayarova 《Materials Sciences and Applications》 2018年第12期965-971,共7页
The impact of Ca and Si nano-scale structures on parameters and density of states of single-crystalline CaF2(111) was studied. It was shown that at low concentration of ions of Ar+ (D ≤ 5 × 1015 cm-2) one witnes... The impact of Ca and Si nano-scale structures on parameters and density of states of single-crystalline CaF2(111) was studied. It was shown that at low concentration of ions of Ar+ (D ≤ 5 × 1015 cm-2) one witnesses formation of nanoscale phases on CaF2 surface. It was revealed that these phases lead to narrowing of the forbidden band Еg between the phases by 4 - 4.5 eV. At higher concentrations (D ≈ 6 × 1016 cm-2) the surface completely is covered by Ca atoms. It was shown that deposition of θ = 10 thick Si single layer on CaF2 surface manifests island picture. The concentration of Ca and Si nano-scale phases on the surface of CaF2 and the band gap of the phases were investigated as a function of (hν) of passing light. Nano-scale phases and nano-scale films of Ca were obtained by using the technique of bombardment with ions of Ar+ of CaF2 surface. Formation of nano-scale phases were accompanied by change in the composition and structure of CaF2 zones located between the phases. These changes led to narrowing of the forbidden band of CaF2 down to 7.5 - 8 eV. The concentration of Ca and Si nano-scale phases on the surface of CaF2 and the band gap of the phases were investigated as a function of (hν) of passing light. 展开更多
关键词 nano-scale Band Gap Hetero-Structures Surface BOMBARDMENT
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Hubble Scale Dark Energy Meets Nano Scale Casimir Energy and the Rational of Their T-Duality and Mirror Symmetry Equivalence
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作者 M.S.El Naschie 《World Journal of Nano Science and Engineering》 2015年第3期57-67,共11页
We establish that ordinary energy, Casimir energy and dark energy are not only interlinked but are basically the same thing separated merely by scale and topology. Casimir energy is essentially a nano scale spacetime ... We establish that ordinary energy, Casimir energy and dark energy are not only interlinked but are basically the same thing separated merely by scale and topology. Casimir energy is essentially a nano scale spacetime phenomenon produced by the boundary condition of the two Casimir plates constituting the Casimir experimental set up for measuring the Casimir force. By contrast dark energy is the result of the cosmic boundary condition, i.e. the boundary of the universe. This one sided M?bius-like boundary located at vast cosmic distance and was comparable only to the Hubble radius scales of the universe. All the Casimir energy spreads out until the majority of it reaches the vicinity of the edge of the cosmos. According to a famous theorem due to the Ukrainian-Israeli scientist I. Dvoretzky, almost 96% of the total energy will be concentrated at the boundary of the universe, too far away to be measured directly. The rest of the accumulated Casimir energy density is consequently the nearly 4% to 4.5%, the existence of which is confirmed by various sophisticated cosmic measurements and observations. When all is said and done, the work is essentially yet another confirmation of Witten’s T-duality and mirror symmetry bringing nano scale and Hubble scale together in an unexpected magical yet mathematically rigorous way. 展开更多
关键词 Mirror Symmetry Casimir Energy Dark Energy Zero Point Vacuum Energy T-DUALITY nano scale-Hubble scale Mobius Holographic Boundary Dvoretzky’s Theorem Banach-Tarski Theorem
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Sin-QuEChERS Nano净化柱结合气相色谱-串联质谱法快速筛查石斛中84种农药残留 被引量:11
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作者 张权 毕珊 +7 位作者 吴玉田 李磊 周贻兵 刘利亚 刘文政 陈庆园 周雪 郭华 《色谱》 CAS CSCD 北大核心 2022年第6期565-575,共11页
利用Sin-QuEChERS Nano净化柱结合气相色谱-串联质谱(GC-MS/MS)分析,建立了石斛基质中84种不同极性农药残留的快速筛查方法。比较了采用不同的提取溶剂(1%乙酸乙腈、丙酮)和不同的提取方式(加水浸泡和不加水浸泡)下目标物的提取效率。... 利用Sin-QuEChERS Nano净化柱结合气相色谱-串联质谱(GC-MS/MS)分析,建立了石斛基质中84种不同极性农药残留的快速筛查方法。比较了采用不同的提取溶剂(1%乙酸乙腈、丙酮)和不同的提取方式(加水浸泡和不加水浸泡)下目标物的提取效率。利用金钗石斛样品系统比较了Sin-QuEChERS Nano法与经典的基质固相分散法(dSPE)、固相萃取法(SPE)、QuEChERS法的净化效果及提取回收率,以及净化效果较好的Sin-QuEChERS Nano法与dSPE法基质效应的差异。目标物经DB-1701MS石英毛细管色谱柱(30 m×0.25 mm×0.25μm)程序升温分离,GC-MS/MS多反应监测(MRM)模式检测,基质匹配溶液外标法定量。通过GC-MS/MS检测方法对金钗石斛和铁皮石斛中的84种代表性农药进行了方法学验证。结果表明:各目标物在不同范围内呈良好的线性相关,相关系数(r^(2))均>0.990,方法的检出限(LOD,S/N=3)为1.5~5.8μg/kg,方法的定量限(LOQ,S/N=10)为5.0~15.0μg/kg。在两个水平下,目标农药的加标回收率为68.7%~116.2%,相对标准偏差(RSD,n=6)均低于15%。与其他经典的前处理方法相比,Sin-QuEChERS Nano法在净化效果方面表现更好,该法不仅可以有效去除色素、有机酸、碱性干扰物等物质,还可以节省样品制备时间,避免溶剂转移造成的损失,无需进一步涡旋或离心,是一种简单而有效的提取物纯化程序。该方法灵敏、快速、简便、可靠,有效地提高了石斛中农药快速筛查时的检测效率,具有较强的实际应用价值。此外,所开发的方法可以进一步扩展目标农药的类型,并可以用于检测其他更多食品及中药材中的农药残留。 展开更多
关键词 气相色谱-串联质谱 Sin-QuEChERS nano净化柱 快速筛查 农药残留 石斛
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Simple-QuEChERS Nano结合GC-MS/MS同时检测全血中的97种农药 被引量:5
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作者 王丹 董林沛 +5 位作者 任昕昕 姜红 王爱华 常靖 张云峰 张曦 《分析测试学报》 CAS CSCD 北大核心 2021年第3期347-355,共9页
建立了Simple-QuEChERS Nano结合气相色谱-串联质谱(GC-MS/MS)同时检测血液中97种农药的方法,并对基质条件、提取溶剂以及净化材料进行了优化。0.5 mL血液样品经3倍水稀释混匀,使用2.0 mL乙酸乙酯提取后振荡、离心,过Simple-QuEChERS N... 建立了Simple-QuEChERS Nano结合气相色谱-串联质谱(GC-MS/MS)同时检测血液中97种农药的方法,并对基质条件、提取溶剂以及净化材料进行了优化。0.5 mL血液样品经3倍水稀释混匀,使用2.0 mL乙酸乙酯提取后振荡、离心,过Simple-QuEChERS Nano净化柱及0.22μm有机微孔滤膜后,采用多反应监测模式(MRM)进行分析。结果显示,97种农药在一定质量浓度范围内线性关系良好(r2≥0.9873),除丙烯菊酯(检出限和定量下限分别为11.03、36.76 ng/mL)外,其余农药的检出限为0.06~4.27 ng/mL,定量下限为0.18~14.24 ng/mL。采用空白全血进行加标回收实验,97种农药在100、200、400 ng/mL 3个加标水平下的回收率为32.2%~120%,日内精密度为1.9%~11%,日间精密度为3.6%~13%。该方法由传统QuEChERS方法改进,绿色环保、操作简单、快速高效,可用于血液中多种农药的同时检测,用于实际案件血液样品中农药的筛查与定性定量检验,获得了良好的结果。 展开更多
关键词 Simple-QuEChERS nano 气相色谱-三重四极杆串联质谱(GC-MS/MS) 血液 农药
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富钴黄铁矿中钴微-纳米尺度赋存状态:以大横路铜钴矿为例 被引量:1
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作者 谢士稳 刘福来 +2 位作者 王慧宁 王舫 龙涛 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第10期3028-3036,共9页
黄铁矿是重要的载钴矿物,自然界钴矿床中富钴黄铁矿的Co含量可达10%~20%,明显超出实验岩石学和理论计算获得的黄铁矿溶解Co的能力。目前,这些富钴黄铁矿溶解过饱和Co的机制以及Co过饱和黄铁矿是否出溶方硫钴矿尚不清楚。为探讨以上问题... 黄铁矿是重要的载钴矿物,自然界钴矿床中富钴黄铁矿的Co含量可达10%~20%,明显超出实验岩石学和理论计算获得的黄铁矿溶解Co的能力。目前,这些富钴黄铁矿溶解过饱和Co的机制以及Co过饱和黄铁矿是否出溶方硫钴矿尚不清楚。为探讨以上问题,本文选取吉林大横路Cu-Co矿中富钴黄铁矿为研究对象。能谱元素面扫描和电子探针分析结果显示,大横路富钴黄铁矿中Co呈不均匀分布且无规律,单颗粒Co含量变化范围较大(Py108为4.31%~9.74%、Py110为4.54%~8.83%),Co的不均匀很可能与黄铁矿的生长过程和结晶环境有关。透射电镜和原子探针分析结果显示,纳米尺度富钴黄铁矿中Co呈均匀分布,未见富Co的包裹体和方硫钴矿出溶体,Co以类质同象的形式替换Fe存在于富钴黄铁矿中。根据以上结果,我们认为大横路富钴黄铁矿中溶解过饱和的Co很可能与微晶尺寸效应有关,亚稳态Co过饱和FeS_(2)-CoS_(2)固溶体可以长期保持不变。 展开更多
关键词 富钴黄铁矿 大横路铜钴矿 黄铁矿-方硫钴矿固溶体 钴赋存状态 -纳米尺度
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Nano-TiO_2/HIPS母料流变性能的研究
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作者 王兆波 王新 张志焜 《塑料工业》 CAS CSCD 北大核心 2004年第1期41-43,56,共4页
采用RosandRheometer流变仪研究了nano -TiO2 /HIPS母料及EVA蜡改性母料的流变性能。结果表明 ,nano TiO2 对母料的表观粘度影响较小 ,在nano TiO2 质量分数低于 2 0 %时 ,表观粘度仅略高于纯HIPS。在低剪切速率下 ,nano TiO2 可加速熔... 采用RosandRheometer流变仪研究了nano -TiO2 /HIPS母料及EVA蜡改性母料的流变性能。结果表明 ,nano TiO2 对母料的表观粘度影响较小 ,在nano TiO2 质量分数低于 2 0 %时 ,表观粘度仅略高于纯HIPS。在低剪切速率下 ,nano TiO2 可加速熔体偏离牛顿流体的速度 ,体系的粘弹性增强 ;而在较高剪切速率下则相反。EVA蜡可在较大范围内调整母料体系的流变性能。在低剪切速率下 ,EVA蜡质量分数超过 5 %就可明显改善体系的流动性 ,且体系流动行为接近牛顿流体 ,粘弹性很弱 ;在高剪切速率下 ,EVA蜡对体系的流动性影响不大 ,流变行为及粘弹行为与纯HIPS相当。原子力显微镜测试表明 ,采用EVA蜡改性的nano TiO2 /HIPS母料 ,可得到表观及分散性良好的制品。 展开更多
关键词 纳米二氧化钛 nano-TiO2/HIPS母料 高抗冲聚苯乙烯 EVA蜡 流变性能 粘弹性 耐冲击性聚苯乙烯
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硅藻土/nano-MoS2复合改性氟橡胶的摩擦磨损性能研究 被引量:4
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作者 谢强 魏刚 +2 位作者 刘燕 许荣霞 魏莉岚 《塑料工业》 CAS CSCD 北大核心 2021年第1期49-54,84,共7页
采用红外光谱仪、无转子硫化仪、环-块摩擦试验机、电子和光学显微镜等测试分析手段,重点考察了改性硅藻土及其与纳米二硫化钼(nano-MoS2)复合对氟橡胶(FKM)复合材料摩擦磨损性能的影响。结果表明,随着改性硅藻土含量的增加,FKM硫化胶... 采用红外光谱仪、无转子硫化仪、环-块摩擦试验机、电子和光学显微镜等测试分析手段,重点考察了改性硅藻土及其与纳米二硫化钼(nano-MoS2)复合对氟橡胶(FKM)复合材料摩擦磨损性能的影响。结果表明,随着改性硅藻土含量的增加,FKM硫化胶的摩擦系数和磨损体积均呈现出逐渐降低的趋势;当改性硅藻土含量达到45 phr时,硫化胶表现出较好的摩擦磨损性能。在此基础上,再添加1 phr的nano-MoS2时,硫化胶具有最低的摩擦系数和体积磨损量,分别为0.4和1.42 mm^3,降低了16.7%和63.6%。SEM分析表明,改性硅藻土的加入有效抑制了氟橡胶的黏着磨损,适量硅藻土和nano-MoS2复合改性氟橡胶表现出轻微的磨粒磨损特征,磨损表面光滑平整,转移膜完整均匀。 展开更多
关键词 氟橡胶 改性硅藻土 纳米二硫化钼 摩擦磨损
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NANO碳净化-超高效液相色谱-串联质谱法测定东北黑土壤中多农残含量 被引量:2
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作者 孟冰冰 于洪春 《分析科学学报》 CAS CSCD 北大核心 2017年第1期91-96,共6页
本文使用NANO碳净化柱对土壤中的31种农药进行净化,并且通过超高效液相色谱-串联质谱法(UPLC-MS/MS)进行测定。土壤样品经过NANO碳净化柱,净化效果良好。31种农药的检出限为0.001~0.01mg/kg,定量限为0.003~0.033mg/kg,添加回收率在70%~1... 本文使用NANO碳净化柱对土壤中的31种农药进行净化,并且通过超高效液相色谱-串联质谱法(UPLC-MS/MS)进行测定。土壤样品经过NANO碳净化柱,净化效果良好。31种农药的检出限为0.001~0.01mg/kg,定量限为0.003~0.033mg/kg,添加回收率在70%~120%之间,相对标准偏差(RSD)在0%~10%之间。结果表明,该方法简单、快捷、灵敏度高,线性范围、回收率和精密度均适合土壤中的31种农药残留检测,在土壤农药残留筛查中具有较好的应用前景。 展开更多
关键词 nano碳纳米净化柱 土壤 农药残留 超高效液相色谱-串联质谱法
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Fabrication and measurement of traceable pitch standard with a big area at trans-scale 被引量:6
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作者 邓晓 李同保 +4 位作者 雷李华 马艳 马蕊 翁浚婧 李源 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期143-147,共5页
Atom lithography with chromium can be utilized to fabricate a pitch standard, which is chrectly traceable to me wavelength of the laser standing waves. The result of a calibrated commercial AFM measurement demonstrate... Atom lithography with chromium can be utilized to fabricate a pitch standard, which is chrectly traceable to me wavelength of the laser standing waves. The result of a calibrated commercial AFM measurement demonstrates that the pitch standard is (212.8±0.1) nm with a peak-to-valley-height (PTVH) better than 20 nm. The measurement results show the high period accuracy of traceability with the standing laser wavelength (λ/2 = 212.78 nm). The Cr nano-grating covers a 1000μm×500 μm area, with a PTVH better than 10 nm. The feature width broadening of the Cr nanostructure has been experimentally observed along the direction of the standing waves. The PTVH along the Gaussian laser direction is similar to a Gaussian distribution. Highly uniform periodic nanostructures with a big area at the millimeter scale, and the surface growth uniformity of the Cr nano-grating, show its great potential in the application of a traceable pitch standard at trans-scales. 展开更多
关键词 atom lithography nano-scale metrology standard TRACEABILITY
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Experimental Study on Molecular Arrangement of Nanoscale Lubricant Films——A Review 被引量:3
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作者 ZHANG Shaohua LIU Yuhong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期896-903,共8页
In order to understand lubrication mechanism at the nanoscale, researchers have used many physical experimental approaches, such as surface force apparatus, atomic force microscopy and ball-on-disk tribometer. The res... In order to understand lubrication mechanism at the nanoscale, researchers have used many physical experimental approaches, such as surface force apparatus, atomic force microscopy and ball-on-disk tribometer. The results show that the variation rules of the friction force, film thicknessand viscosity of the lubricant at the nanoscale are different from elastohydrodynamic lubrication (EHL). It is speculated that these differences are attributed to the special arrangement of the molecules at the nanoscale. However, it is difficult to obtain the molecular orientation and distribution directly from the lubricant molecules in these experiments. In recent years, more and more attention has been paid to use new techniques to overcome the shortcomings of traditional experiments, including various spectral methods. The most representative achievements in the experimental research of molecular arrangement are reviewed in this paper: The change of film structure of a liquid crystal under confinement has been obtained using X-ray method. The molecular orientation change of lubricant films has been observed using absorption spectroscopy. Infrared spectroscopy has been used to measure the anisotropy of molecular orientation in the contact region when the lubricant film thickness is reduced to a few tens of nanometers. In situ Raman spectroscopy has been performed to measure the molecular orientation of the lubricant film semi-quantitatively. These results prove that confinement and shear in the contact region can change the arrangement of lubricant molecules. As a result, the lubrication characteristics are affected. The shortages of these works are also discussed based on practicable results. Further work is needed to separate the information of the solid-liquid interface from the bulk liquid film. 展开更多
关键词 nano-scale lubricating film in situ measurement molecular arrangement
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Elastic modulus of claystone evaluated by nano-/micro-indentation tests and meso-compression tests 被引量:5
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作者 Christophe Auvray Noémie Lafrance Danièle Bartier 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第1期84-91,共8页
Toarcian claystone such as that of the Callovo-Oxfordian is a qualified multiphase material. The claystone samples tested in this study are composed of four main mineral phases: silicates(clay minerals, quartz,feldspa... Toarcian claystone such as that of the Callovo-Oxfordian is a qualified multiphase material. The claystone samples tested in this study are composed of four main mineral phases: silicates(clay minerals, quartz,feldspars, micas)(z86%), sulphides(pyrite)(z3%), carbonates(calcite, dolomite)(z10%) and organic kerogen(z1%). Three sets of measurements of the modulus of deformability were compared as determined in(i) nanoindentation tests with a constant indentation depth of 2 mm,(ii) micro-indentation tests with a constant indentation depth of 20 mm, and(iii) meso-compression tests with a constant displacement of 200 mm. These three experimental methods have already been validated in earlier studies. The main objective of this study is to demonstrate the influence of the scaling effect on the modulus of deformability of the material. Different frequency distributions of the modulus of deformability were obtained at the different sample scales:(i) in nano-indentation tests, the distribution was spread between 15 GPa and 90 GPa and contained one peak at34 GPa and another at 51 GPa;(ii) in the micro-indentation tests, the distribution was spread between 25 GPa and 60 GPa and displayed peaks at 26 GPa and 37 GPa; and(iii) in the meso-compression tests, a narrow frequency distribution was obtained, ranging from 25 GPa to 50 GPa and with a maximum at around 35 GPa. 展开更多
关键词 Claystone Elastic modulus Scaling effect nano-and micro-indentation Meso-compression tests Multi-scale mechanical tests
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Morphology Difference between the Alkali Activated Cement and Portland Cement Paste on Multi-scale 被引量:1
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作者 沈卫国 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第6期923-926,共4页
The features of alkali activated slag(AAS) and portland cement (PC) were observed on multi-scale,the crack and fracture sections were observed with naked eyes,and SEM and AFM were used to study the structure morph... The features of alkali activated slag(AAS) and portland cement (PC) were observed on multi-scale,the crack and fracture sections were observed with naked eyes,and SEM and AFM were used to study the structure morphology differences between PC and AAS on micrometer to nano meter scale.The experimental results indicated that the AAS paste had soil like fracture texture and it was composed of mainly C-S-H gel but lacks of crystals,and it had a very strong tendency to shrink and crack.AAS paste is much denser and more homogeneous than PC,and on the nano scale C-S-H nano particle in the AAS paste is much smaller and packs much denser than PC paste. 展开更多
关键词 MORPHOLOGY alkali activated cement portland cement MULTI-scale nano particle
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