期刊文献+
共找到1,881篇文章
< 1 2 95 >
每页显示 20 50 100
ISOLATION DESIGN AND SIMULATIONAL EXPERIMENT OF NANOMETER MICRO MOVEMENT TEST-BED
1
作者 吴晓琳 刘平成 +1 位作者 杨圣 杨晓红 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期200-205,共6页
The relation of mass, stiffness and rate of damping is obtained by using the mechanical analysis of the obstructive vibration system of two dimensions for the design of the obstructive vibration system of more freedom... The relation of mass, stiffness and rate of damping is obtained by using the mechanical analysis of the obstructive vibration system of two dimensions for the design of the obstructive vibration system of more freedom and the micro vibration test bed. The result of stimulational experiment indicates that the isolation of vibration of this system is satisfactory. The design method of vibration can be used as the reference to ultra precision machine tool, super micro orientation machanism and so on. 展开更多
关键词 nanometer (NM) micro vibration test bed isolation of vibration simulation transmission quotiety
下载PDF
Mechanical Characterization of Electroplated Ni Films by Micro-tensile Testing 被引量:3
2
作者 ZHANG Duanqin CHU Jinkui 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第4期557-561,共5页
Mechanical properties of structural materials are particularly important for design, performance realization and reliability analysis of microelectromechanical systems (MEMS). Furthermore, accurate database of mecha... Mechanical properties of structural materials are particularly important for design, performance realization and reliability analysis of microelectromechanical systems (MEMS). Furthermore, accurate database of mechanical properties at the micro scale can provide indispensable reference for establishing MEMS standard. Electroplated nickel film is one of the most favored structural materials used in MEMS, thus its mechanical properties has been studied for many years. However, the measured values show large scatter in Yotmg's modulus of nickel film. Young's modulus and yield stress of electroplated nickel film are measured by using a micro-tensile testing instrument. The tensile load applied on the specimen is measured by a load cell with accuracy 0.25 mN directly, without additional friction. Through measuring the axial stiffness coefficient of the tensile instnunent in situ, the tensile strain of the specimen is obtained by using two-serial spring model. The electroplated nickel films were fabricated from sulfarnate baths, and the gauge section is 500μm long and 10μm wide nominally, and thickness range between 25 μm and 50μm. The obtained Young's modulus from tensile testing is 83+6 GPa for nickel specimens electroplated at current density of 20 mA/cm2 and it increases to 124+5 GPa as current density is decreased to 10 mA/cm2. The phenomena are interpreted in terms of porosity of microstructure. The higher current density produced rnicrostucture with low density and high volume fraction of pores, and the microstructure of high porosity corresponds to a lower modulus. The measured values of Young's modulus are consistent with those of calculated from the exponential empirical formula between Young's modulus and porosity. The micro-tensile testing instrument can also be used for mechanical measurement of other MEMS films. 展开更多
关键词 electroplated nickel micro-tensile testing Young's modulus POROSITY
下载PDF
Measurement of Ca^(2+) Flow in Cochlear Cells Using Non-Invasive Micro-Test Technique 被引量:1
3
作者 CHEN Shi-qin YU Ning +2 位作者 YE Sheng-nan YANG Shi-ming ZHAI Suo-qiang 《Journal of Otology》 2010年第2期90-96,共7页
Objective To test Calcium ion(Ca2+) flow at the head and end of outer hair cells(OHCs) in resting state and in response to Nimodipine treatment.Methods Non-invasive micro-test techniques were used to study Ca2+ in iso... Objective To test Calcium ion(Ca2+) flow at the head and end of outer hair cells(OHCs) in resting state and in response to Nimodipine treatment.Methods Non-invasive micro-test techniques were used to study Ca2+ in isolated OHCs in adult guinea pigs.Results Four types of Ca2+ transport were identified in OHCs on basilar membrane tissue fragments:influx at the head of with efflux at the bottom(type 1):efflux at the head of OHCs with influx at the bottom(type 2);influx at the both head and bottom(type 3);and efflux at the both head and bottom(type 4).However,only type 1 and type 3 of Ca2+ ion transport were detected in the cochlea.We propose that Ca2+ ion transport exists in adult guinea pig cochlear OHCs in resting state and is variable.Ca2 + flow in OHC can be inhibited by Nimodipine in resting state. 展开更多
关键词 Guinea pig outer hair cells Ca2+ ion non-invasive micro-test technique nimodipine.
下载PDF
Comparison of mechanical properties in welded joint for CO_2 arc welding by using the micro-shear test and impact test
4
作者 Zhou Lixia Wang Shiyuan and Shi Yaowu (Xi’an Jiaotong University)L. Dorn(Technical University of Berlin) 《China Welding》 EI CAS 1995年第1期57-64,共8页
A micro shear testing method which can suit to measure the mechanical properties of heterogeneous materials is introduced, and the properties in each zone of welded joint for CO2 arc welding can be evaluated by using ... A micro shear testing method which can suit to measure the mechanical properties of heterogeneous materials is introduced, and the properties in each zone of welded joint for CO2 arc welding can be evaluated by using this method in this paper. Moreover, these results are compared with those results of Charpy V-notch impact test and their correlation is discussed. 展开更多
关键词 mechanical properties micro shear test CO_2 arc welding WELDED
下载PDF
Elastic modulus of claystone evaluated by nano-/micro-indentation tests and meso-compression tests 被引量:5
5
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
下载PDF
Vibration test of micro machined gyroscope based on high speed photography and SURF 被引量:1
6
作者 姚峰林 高世桥 +1 位作者 赵婕 高崇仁 《Journal of Beijing Institute of Technology》 EI CAS 2012年第2期179-184,共6页
Based on three kinds of dynamic test of MEMS, a dynamic system for the vibration test of micro machined gyroscope based on high speed photography is introduced. Firstly, the architecture of the system hardware is intr... Based on three kinds of dynamic test of MEMS, a dynamic system for the vibration test of micro machined gyroscope based on high speed photography is introduced. Firstly, the architecture of the system hardware is introduced. Secondly, the image tracking performance is compared by the test using the template matching algorithm, the mean shift algorithm and the SURF algorithm. The vibration curve shows that high speed photograph combined with SURF algorithm is faster, more ac- curate, and more suitable for the vibration test of micro machined gyroscope. After the frequency a- nalysis and related interpolation, more characteristics of micro gyroscope can be obtained. 展开更多
关键词 high speed photograph SURF micro machined gyroscope dynamic test VIBRATION IMAGE
下载PDF
Micro-Doppler effect testing technique for attitude of projectile in space flight
7
作者 张万君 吴晓颖 +2 位作者 张晓炜 牛敏杰 冷雪冰 《Journal of Beijing Institute of Technology》 EI CAS 2013年第3期350-353,共4页
To measure projectile attitude in space flight, based on continuous wave (CW) radar, a new micro-Doppler effect testing technique is developed in this paper. It also establishes radar testing model for attitude of f... To measure projectile attitude in space flight, based on continuous wave (CW) radar, a new micro-Doppler effect testing technique is developed in this paper. It also establishes radar testing model for attitude of flying projectile and resolve micro-Doppler effect of projectile motion attitude. By distinguishing and geting attitude parameters such as micro-motion period, this technique can in- tuitively estimate the flight stability of projectile, and the validity of this technique is proved accord- ing to flight tests. 展开更多
关键词 attitude of projectile micro-DOPPLER radar testing target micro-motion
下载PDF
China,America Have Coo[erated in Micro Biological Production Test
8
作者 Hou Fu 《China Oil & Gas》 CAS 1996年第3期189-189,共1页
China,AmericaHaveCooperatedinMicrobiologicalProductionTestHouFuThemicrobiologicalproductiontechnologyhasbeen... China,AmericaHaveCooperatedinMicrobiologicalProductionTestHouFuThemicrobiologicalproductiontechnologyhasbeenintroducedfromthe... 展开更多
关键词 China America Have Coo[erated in micro Biological Production test
下载PDF
Salt spray corrosion test of micro-plasma oxidation ceramic coatings on Ti alloy 被引量:3
9
作者 HAO Guodong YAO Zhongping JIANG Zhaohua 《Rare Metals》 SCIE EI CAS CSCD 2007年第6期560-564,共5页
Ceramic coatings were prepared on Ti-6Al-4V alloy in NaAlO2 solution by micro-plasma oxidation (MPO). The salt spray tests of the coated samples and the substrates were carded out in a salt spray test machine. The p... Ceramic coatings were prepared on Ti-6Al-4V alloy in NaAlO2 solution by micro-plasma oxidation (MPO). The salt spray tests of the coated samples and the substrates were carded out in a salt spray test machine. The phase composition and surface morphology of the coatings were investigated by XRD and SEAM. Severe corrosion occurred on the substrate surface, while there were no obvious corrosion phenomena on the coated samples. The coatings were composed of Al2TiO5 and a little α-Al2O3 and mille TiO2, and the salt spray test did not change the composition of the coatings. The weight loss rate of the coatings decreased with increasing MPO time because of the increase in density and thickness of the coatings. The surface morphology of the coatings was influenced by salt spray corrosion test. Among the coated samples, the coating prepared for 2 h has the best corrosion resistance under salt spray test. 展开更多
关键词 micro-plasma oxidation ceramic coating salt spray corrosion test Ti alloy
下载PDF
Experimental Tests on a Pre-Heated Combustion Chamber for Ultra Micro Gas Turbine Device: Air/Fuel Ratio Evaluation
10
作者 Roberto Capata Kliton Kylykbashi +1 位作者 Alfonso Calabria Mario Di Veroli 《Engineering(科研)》 2016年第11期789-805,共17页
Current portable power generators are mainly based on internal combustion engine since they present higher values of efficiency comparing to other engines;the main reason why internal combustion engine is not convenie... Current portable power generators are mainly based on internal combustion engine since they present higher values of efficiency comparing to other engines;the main reason why internal combustion engine is not convenient for micro power generation (5 - 30 kW) is because of their heaviness. Micro and ultra micro gas turbine devices, based on a micro compressor and a micro turbine installed on the same shaft, are more suitable for this scope for several reasons. Micro turbine systems have many advantages over reciprocating engine generators, such as higher power density (with respect to size and weight), extremely low emissions and few, or just one, moving part. Those designed with foil bearings and air-cooling operate without oil, coolants or other hazardous materials. Micro turbines also have the advantage of having the majority of their waste heat contained in their relatively high temperature exhaust. Micro turbines offer several potential advantages compared to other technologies for small-scale power generation, including: a small number of moving parts, compact size, lightweight, greater efficiency, lower emissions, lower electricity costs, and opportunities to utilize waste fuels. The object of this study is the experimental tests on a stand-alone gas turbine device with a pre-heated combustion chamber (CC), to validate the fuel consumption reduction, compared to an actual and commercial device, used on air models. 展开更多
关键词 Experimental tests Combustion Chamber Ultra micro Gas Turbine Fuel Consumption
下载PDF
水软化作用下页岩微观结构和力学性质演化特性
11
作者 罗攀登 赵兵 +1 位作者 冯禹菲 张妹珠 《金属矿山》 CAS 北大核心 2024年第8期29-34,共6页
在雨水或者地下水的浸泡下,页岩力学性质会大幅度降低,容易导致泥石流、隧洞塌陷、滑坡等灾害。以页岩为研究对象,通过微观岩石力学试验研究了水软化作用下页岩的微观结构和力学特性演变规律。研究结果表明:在浸水10 d后,页岩表面粗糙... 在雨水或者地下水的浸泡下,页岩力学性质会大幅度降低,容易导致泥石流、隧洞塌陷、滑坡等灾害。以页岩为研究对象,通过微观岩石力学试验研究了水软化作用下页岩的微观结构和力学特性演变规律。研究结果表明:在浸水10 d后,页岩表面粗糙度平均值和最大值分别增至259.1 nm和561.9 nm。页岩主要由石英、绿泥石、伊利石和钠长石组成,其中绿泥石为层状硅酸盐。在水软化作用下绿泥石发生崩解并且释放晶层间膨胀力,导致页岩样品粗糙度增加。随着浸水时间的增加,高、中、低3类强度矿物的弹性模量逐渐减小;低强度矿物的黏聚力呈现下降趋势,从16.7 MPa降低到6.0 MPa,而内摩擦角随浸泡时间轻微波动,其平均值为42.5°。 展开更多
关键词 页岩 水软化 微观岩石力学试验 纳米压痕试验
下载PDF
G.654.E微型光缆在骨干光缆网中的应用研究
12
作者 张曜晖 赵璋卓 +1 位作者 王浩 黄劲松 《邮电设计技术》 2024年第6期63-66,共4页
G.654.E微型光缆作为一种全新的光缆类型,尚未在国内各大运营商干线光缆网中规模应用。为了验证G.654.E微型光缆的可用性,中国联通组织了相关厂商制作样品并进行测试。深入分析了测试数据,从结构尺寸、PMD参数、机械性能、温度循环特性... G.654.E微型光缆作为一种全新的光缆类型,尚未在国内各大运营商干线光缆网中规模应用。为了验证G.654.E微型光缆的可用性,中国联通组织了相关厂商制作样品并进行测试。深入分析了测试数据,从结构尺寸、PMD参数、机械性能、温度循环特性等7个方面论证了G.654.E微型光缆的性能指标,为该型光缆在中国联通骨干光缆网中的应用提供试验基础,同时也为其他运营商的使用提供参考。 展开更多
关键词 G.654.E光纤 微型光缆 测试
下载PDF
非常规储层微纳米孔隙介质中流体相态研究进展
13
作者 汪周华 范琨鹏 +4 位作者 赵建飞 余曹 匡红先 郭平 涂汉敏 《世界石油工业》 2024年第3期68-77,共10页
非常规油气储层具有岩石骨架颗粒小、比表面积大、微纳米孔隙发育的特点,流体与孔隙介质间存在着诸多复杂的界面效应问题,影响微纳米孔隙介质中流体的相态变化规律。对于受限域流体,经典油气相态理论方法忽略分子间相互作用及界面效应... 非常规油气储层具有岩石骨架颗粒小、比表面积大、微纳米孔隙发育的特点,流体与孔隙介质间存在着诸多复杂的界面效应问题,影响微纳米孔隙介质中流体的相态变化规律。对于受限域流体,经典油气相态理论方法忽略分子间相互作用及界面效应的影响,预测微纳米孔隙介质中流体相变特征存在偏差。为了更全面地揭示油气在受限空间中的相态特征及其微观作用机理,总结当前微纳米孔隙介质中流体相态研究技术现状,详细阐述微观实验测试、相态理论模型和分子模拟3种主流技术方法,指出3种技术各自的优缺点,并对未来流体相态研究技术提出展望。分析认为:微观实验测试方法可通过研究流体热力学参数的变化来确定流体相变点,由于实验误差、人为误差等原因,需与理论计算相结合;相态理论模型方法可通过改进临界参数场、考虑流体与孔壁界面作用、考虑相间毛管压力修正相平衡判据方程等方法建立纳米孔隙空间相态理论模型,但是由于没有综合考虑界面效应带来的影响且缺乏有力的实验数据支撑,难以推广应用;分子模拟方法能在分子尺度上揭示流体分子的相行为,但现有研究主要围绕小分子展开,并且与流体发生相变时的临界参数结合得较少。后续研究应以多界面效应耦合影响的微纳米孔隙介质中油气流体相变特征为研究对象,以微观实验、理论模型和分子模拟为技术手段,为描述微纳米孔隙介质中流体相态提供合理的实验测试手段和可靠的理论计算模型。 展开更多
关键词 流体相态 微观实验测试 相态理论模型 分子模拟 油气藏开发
下载PDF
FZG齿轮试验机方法在齿轮油上的应用研究
14
作者 石啸 雷凌 +2 位作者 杨晓晨 曹静思 赵海鹏 《润滑油》 CAS 2024年第2期29-36,共8页
齿轮箱设备所用齿轮油最为关键的性能是承载性能。常规理化测试不足以全面评价齿轮油的承载性能,因此国内外研究机构结合机械设备开发了许多评价齿轮油承载性能的试验方法。研究表明:简单的台架测试方法一般与设备实际工况相关性差,在... 齿轮箱设备所用齿轮油最为关键的性能是承载性能。常规理化测试不足以全面评价齿轮油的承载性能,因此国内外研究机构结合机械设备开发了许多评价齿轮油承载性能的试验方法。研究表明:简单的台架测试方法一般与设备实际工况相关性差,在齿轮试验台上使用指定几何结构的齿轮可以更好地表征齿轮润滑剂的承载性能。文章主要阐述了润滑剂对齿轮不同失效模式的影响,以及如何用适当的测试方法量化,并准确表征润滑剂的承载性能。 展开更多
关键词 FZG 齿轮试验机 擦伤 磨损 微点蚀
下载PDF
安全帽送风强度对人体呼吸微环境影响研究
15
作者 孟晓静 薛鑫鑫 +2 位作者 付林志 刘启薇 黄玉杰 《安全与环境学报》 CAS CSCD 北大核心 2024年第9期3335-3342,共8页
为改善作业人员呼吸微环境,对送风式安全帽佩戴者呼吸微环境温度场、速度场和浓度场进行研究。通过假人试验方法测试安全帽在不同送风强度下的人体呼吸微环境温度、速度和粉尘质量浓度,研究人体呼吸微环境温度分布及速度分布规律,阐明... 为改善作业人员呼吸微环境,对送风式安全帽佩戴者呼吸微环境温度场、速度场和浓度场进行研究。通过假人试验方法测试安全帽在不同送风强度下的人体呼吸微环境温度、速度和粉尘质量浓度,研究人体呼吸微环境温度分布及速度分布规律,阐明安全帽送风强度对人体呼吸微环境中总尘及呼尘降尘效果的影响,进而分析佩戴者对安全帽送风强度的满意程度。结果显示,人体面中部位降温效果优于人体脸颊两侧,其中人体鼻子处降温效果较为明显;安全帽在不同送风强度下对人体呼吸微环境速度场的分布规律一致;当送风强度为Ⅳ级时,人体呼吸微环境内粉尘降尘效率最高,佩戴者满意率最高;人体微环境总尘和呼尘降尘效率分别可达到81.39%和82.89%。研究结果可为改善人体呼吸微环境提供参考。 展开更多
关键词 安全卫生工程技术 安全帽 送风强度 假人试验 呼吸微环境
下载PDF
竞争ELISA和间接ELISA方法应用于牛布鲁氏菌病净化的研究 被引量:1
16
作者 赵灿奇 冯宇 +5 位作者 吕浪 李彦军 魏玉磊 丁家波 陈祥 蒋卉 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第5期2146-2153,共8页
旨在评价竞争ELISA方法和间接ELISA方法联合使用在布鲁氏菌病(以下简称“布病”)净化中的效果,为布病防控提供技术支撑。采用本实验室开发的动物布鲁氏菌病竞争ELSIA(cELISA)抗体检测试剂盒、牛布鲁氏菌病间接ELISA(iELISA)抗体检测试... 旨在评价竞争ELISA方法和间接ELISA方法联合使用在布鲁氏菌病(以下简称“布病”)净化中的效果,为布病防控提供技术支撑。采用本实验室开发的动物布鲁氏菌病竞争ELSIA(cELISA)抗体检测试剂盒、牛布鲁氏菌病间接ELISA(iELISA)抗体检测试剂盒及微量法补体结合试验(mCFT),对西北某牛场3 271份牛血清进行检测。本研究采用cELISA初筛、iELISA确诊的净化策略,对检测阳性牛进行淘汰,可疑牛和阴性牛在完全消毒后隔离饲养,并在前一次检测后每隔1个月重新对群体采样,进行多次连续的“检—淘”策略,在群体的个体阳性率低于2%或全部转阴后使用微量补体结合试验(mCFT)进行验证。并在群体全部转阴后继续检测2个月后确定净化结果。结果显示,首次检测阳性率35.36%的感染群体实施本净化策略后,在第1个月阳性率下降至25.41%,第2个月下降至7.16%,第3个月下降为1.86%,到第4个月则实现了布病阳性群体的全面转阴,mCFT验证个体阴性率100%。此后持续检测2个月,个体阳性率均为0,至此实现了感染群体的布病净化,使得群体内近一半的牛免于扑杀,大大减少了经济损失。综上发现,将cELISA用于布病初筛,iELISA用于布病确诊的联合使用,经多次连续检测并结合常规的隔离消毒措施,可以在短时间内实现对于布病感染群体的全面净化。 展开更多
关键词 布鲁氏菌病 竞争酶联免疫吸附试验 间接酶联吸附试验 微量补体结合试验 初筛 确诊
下载PDF
微型木桩的群桩效应研究
17
作者 刘润 彭佳俊 +1 位作者 梁超 李成凤 《地基处理》 2024年第1期23-30,共8页
木材广泛存在于我国村镇中,其取材加工方便,价格低廉,用作村镇住宅的基础结构,可有效减少村镇住宅的能源消耗,符合绿色建筑理念。本文以微型木桩为研究对象,通过离心机模型试验和有限元数值分析,研究了微型木桩在砂土和粉质黏土土层条... 木材广泛存在于我国村镇中,其取材加工方便,价格低廉,用作村镇住宅的基础结构,可有效减少村镇住宅的能源消耗,符合绿色建筑理念。本文以微型木桩为研究对象,通过离心机模型试验和有限元数值分析,研究了微型木桩在砂土和粉质黏土土层条件下的群桩承载力和群桩效应系数。结果表明,微型木桩的群桩效应系数η在砂土中大于1,在黏土中小于1,受桩土刚度比的影响较小;桩径减小改变了群桩最优桩间距,砂土中微型木桩η随着桩的距径比Sa/D的增大逐渐增大,在Sa/D=6时出现峰值,常规桩在Sa/D=3时达到最大,微型木桩最优桩间距大于常规桩;黏土中,微型木桩η峰值对应的Sa/D=4小于常规桩η峰值对应的Sa/D=6,微型木桩最优桩间距小于常规桩;微型木桩群桩效应系数随内摩擦角和不排水抗剪强度的增大而减小,随距径比的增大先增加后减小,随桩数的增加而增大。 展开更多
关键词 微型桩 木桩 离心机模型试验 群桩效应 数值模拟
下载PDF
高碳铬铁渣微表处混合料路用性能研究
18
作者 王国忠 付靖超 +1 位作者 贾永杰 王履泽 《黑龙江交通科技》 2024年第5期33-37,41,共6页
针对道路养护工程优质石料资源匮乏,高碳铬铁渣大多采用堆存处理且利用率低等问题,将高碳铬铁渣分别以0%、20%、30%、40%、50%、60%的掺量替换常规微表处混合料,通过湿轮磨耗试验、车辙试验、黏聚力试验和构造深度试验研究不同高碳铬铁... 针对道路养护工程优质石料资源匮乏,高碳铬铁渣大多采用堆存处理且利用率低等问题,将高碳铬铁渣分别以0%、20%、30%、40%、50%、60%的掺量替换常规微表处混合料,通过湿轮磨耗试验、车辙试验、黏聚力试验和构造深度试验研究不同高碳铬铁渣掺量下的微表处混合料的路用性能。试验结果表明:高碳铬铁渣掺量为20%时,混合料的耐磨耗性能和水稳定性与常规微表处混合料相近,抗车辙性能略有下降,早期强度和抗滑性能均优于常规微表处混合料。 展开更多
关键词 高碳铬铁渣 微表处 湿轮磨耗试验 车辙试验 黏聚力试验
下载PDF
深基坑双排微型桩-锚-撑组合支护结构受力与变形特性
19
作者 闫楠 郝增明 +3 位作者 白晓宇 张立 孙林娜 张启军 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第6期2295-2309,共15页
为深入研究深厚杂填土地层深基坑微型桩-锚-撑组合支护结构随基坑开挖的受力与变形演化规律,首先,依托青岛市某深基坑工程开展双排微型桩-锚-撑原位试验,分析开挖工况下前、后排桩的桩身弯矩分布规律;然后,结合ABAQUS有限元模拟方法,明... 为深入研究深厚杂填土地层深基坑微型桩-锚-撑组合支护结构随基坑开挖的受力与变形演化规律,首先,依托青岛市某深基坑工程开展双排微型桩-锚-撑原位试验,分析开挖工况下前、后排桩的桩身弯矩分布规律;然后,结合ABAQUS有限元模拟方法,明确微型桩、预应力锚索与钢支撑之间的协同作用及基坑变形规律;最后,揭示微型桩桩径变化、支护结构作用对桩身受力及基坑变形的影响机制。研究结果表明:增加开挖深度引起桩身正弯矩和负弯矩不断增大,极值点位置不断下移,桩身弯矩整体呈正“S”形分布;开挖至基底,前排桩的桩身反弯点分别位于钢支撑下方0.5 m和开挖面位置,后排桩的桩身反弯点分别位于钢支撑下方0.5 m和开挖面下方1.0 m范围内;基坑开挖竖向影响范围约为1.35H(H为基坑开挖深度),桩径增加近1倍,土体水平位移仅减少约51%,且随桩径继续增加,其对于限制基坑变形效果不显著;相较于桩锚支护结构,桩-锚-撑支护结构作用下,前、后排桩的最大水平位移分别减小34.9%和27.3%,基坑土体的最大水平位移减小46.0%。 展开更多
关键词 深基坑 微型桩 锚索 钢支撑 原位试验 有限元模拟
下载PDF
大理州牛羊布鲁氏菌病血清学流行病学调查分析
20
作者 赵灿奇 冯宇 +5 位作者 吕浪 苏晓玲 康德玛 陈祥 丁家波 蒋卉 《中国人兽共患病学报》 CAS CSCD 北大核心 2024年第3期270-275,共6页
目的检测大理州牛羊布鲁氏菌抗体,了解和掌握云南大理地区的家畜布鲁氏菌病流行现状。方法采用动物布鲁氏菌竞争ELISA(cELISA)抗体检测方法、牛布鲁氏菌间接ELISA(iELISA)抗体检测方法、羊布鲁氏菌间接ELISA(iELISA)抗体检测方法、布鲁... 目的检测大理州牛羊布鲁氏菌抗体,了解和掌握云南大理地区的家畜布鲁氏菌病流行现状。方法采用动物布鲁氏菌竞争ELISA(cELISA)抗体检测方法、牛布鲁氏菌间接ELISA(iELISA)抗体检测方法、羊布鲁氏菌间接ELISA(iELISA)抗体检测方法、布鲁氏菌荧光偏振(FPA)方法等4种不同方法,分别对大理州12县(市)2022年的18640份家畜血清进行检测,其中牛血清样品7813份、羊血清样品10827份。最后采用微量法补体结合试验(mCFT)对cELISA、iELISA和FPA检测阳性的样品进行确诊。结果大理州羊血清mCFT确诊阳性189份,阳性率为1.75%(189/10827),其中大理市1.90%(2/105)、宾川县4.23%(34/803)、祥云县2.53%(19/752)、巍山县1.58%(12/760)、洱源县2.52%(22/873)、剑川县2.00%(91/4554)、云龙县1.54%(9/585),牛血清布病抗体阳性率均为0。cELISA、iELISA和FPA 3种方法检测出的阳性样品采用mCFT进行确诊时,mCFT确诊的阳性样品与这3种方法检测阳性样品之间的符合率分别为75.00%,100.00%和98.81%,其中iELISA与mCFT符合率最高。结论大理州牛群未检测到布病抗体阳性,感染风险低;羊群布鲁氏菌感染率高,12个县(市)中有7个县(市)检出羊布病阳性样品,绘制的大理州羊布病流行情况分布图为今后有效防控和净化畜间布病提供基础数据和技术支撑。 展开更多
关键词 布鲁氏菌病 荧光偏振试验 微量法补体结合试验 流行病学 大理
下载PDF
上一页 1 2 95 下一页 到第
使用帮助 返回顶部