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1.
采用石英晶体微天平(QCM)技术动态监测三氯甲烷在[Cu(C24H22N4O3)]·CH2Cl2金属有机框架膜(Cu—MOFs)上的吸附动力学.吸附与解吸过程中膜质量的变化由QCM的频率变化实时传感测量,结果表明,吸附过程符合假二级动力学模型,其中在三氯甲烷蒸气压条件下的吸附速率常数为在1.01×10^5PaNz存在下速率常数的1.4-2.1倍,半数以上的吸附量相对于气相浓度稀释呈现可逆吸附特征。吸附等温线符合Langmuir等温式,在蒸气压与1.01×10^5PaN2存在条件下(25℃),三氯甲烷在厚度为0.337μm Cu—MOFs上吸附的平衡常数分别为6.47与3.93L/g,最大吸附量分别为27.2与24.7μg/cm^2。  相似文献   

2.
内蒙古某低品位铅锌矿成份复杂,矿石中的金属矿物占矿物相对含量的7.23%,矿物之间的嵌布关系较为复杂,难以解离。对该矿进行生物浸出,研究结果表明:当矿浆浓度10%,粒度〈40μm占80%,20×10~7 cell·m L^(-1)菌液接种方式,初始p H值1.8,初始电位650 m V,浸出温度45℃,充气量为0.8 m^3·h^(-1)时,锌浸出率接近100%。生物浸出的浸出率是直接酸浸的7倍,矿石粒度3.9~10 mm和间歇喷淋有利于生物柱浸。  相似文献   

3.
采用0.5μm标准CMOS工艺和微机械加工工艺,设计并制作了低成本4×4钨微测辐射热计阵列集成芯片。阵列中每个钨微测辐射热计均由微悬桥结构和钨热敏电阻组成,CMOS读出电路集成在阵列下方。微悬桥结构由表面牺牲层技术实现,不需要任何的光刻工艺。钨微测辐射热计像元尺寸为100μm×100μm,填充因子为20%。测试结果表明,在真空环境下,钨微测辐射热计等效热导为1.31×10-4W/K,等效热容为1.74×10-7J/K,热时间常数为1.33 ms。当红外光源的斩波频率为10 Hz时,钨微测辐射热计的电压响应率为1.91×103V/W,探测率为1.88×107cm·Hz1/2/W。  相似文献   

4.
单晶硅广泛应用于MEMS器件中。根据等效刚度原理,单晶硅可以简化为各向同性材料。介绍了一种采用湿法腐蚀工艺加工的倾斜硅梁,并利用频率响应特性测试了其等效杨氏模量和等效泊松比。采用(100)硅片制作了八组不同尺寸参数的倾斜硅梁。梁的宽度尺寸间隔为30μm,尺寸范围为30μm~240μm,对应宽高比为1/8~1。实验结果证明了等效杨氏模量与倾斜梁尺寸无关,而等效泊松比不仅和单晶硅的特性相关,而且受倾斜梁尺寸的影响。实验得到的等效杨氏模量为170.51 GPa±2.08 GPa。对等效泊松比的测量结果在Matlab中进行了多项式拟合,7次拟合多项式已经与测试结果具有很好的一致性。  相似文献   

5.
制备了聚硫堇(PTh)-磁性核,壳纳米粒子CoFe2O4/SiO2修饰电极。研究了神经递质多巴胺(DA)在该修饰电极上的电化学行为。实验表明,PTh—CoFe2O4/SiO2复合膜修饰电极对DA的电催化作用优于PTh修饰电极。在pH7.5的PBS中,DA在该修饰电极上的CV曲线于-0.16V和-0.22V处出现一对灵敏的氧化还原峰,峰电流显著增加。差分脉冲伏安法(DPV)氧化峰电流ips与DA浓度在1.2×10^-7-3.6×10^-5mol/L范围内呈良好的线性关系,线性回归方程ips(μA)=5.307c(μmol/L)+0.7891,r=0.9923,检出限为6.0×10^-8mol/L(S/N=3)。常见物质对DA的检测无干扰,DA注射液样品检测结果与中国药典2010版(二部)规定方法一致。  相似文献   

6.
用循环伏安法制备了铜掺杂聚L-天冬氨酸修饰玻碳电极,研究了多巴胺(DA)和尿酸(UA)在该修饰电极上的电化学行为,建立了同时测定DA和UA的新方法。在pH3.5的磷酸盐缓冲溶液中,扫描速率为120mV]s时,DA和UA在该电极上产生氧化还原峰,峰电位分别为Eps=0.429V、Epc=0.336V(DA)和Eps=0.617V(UA),DA和UA的氧化峰分开达0.188V。采用循环伏安法(CV法)和示差脉冲伏安法(DPVs法)同时测定DA和UA的线性范围分别为:DA:3.00×10^-6-4.00×100mol/L、4.00×10^-5~1.00×10^-4mlo/L(CV)、3.00×10^-7~3.00×10^-6mol/L、3.00×10^-6—1.00×10^-5mol/L(DPVs),UA:8.00×10^-6~5.00×10^-5mol/L、5.00×10^-5-2.00×10^-4mol/L(CV)、3.00×10^-7~5.00×10^-5mol/L、5.00×10^-5.2.00×10^-4mol/L(DPVs);检出限分另U为8.0×10^-7mol/L、1.0×10^-6mol/L(CV)和3.0×10^-7mol/L、3.0×10^-7mol/L(DPVs)。用于人体尿液中DA和UA的同时测定,结果满意。  相似文献   

7.
为研究SiC/Al梯度功能材料(Functionally Gradient Material,FGM)的性能,采用ANSYS分别对具有4个梯度层的该种材料的3点弯曲试样和紧凑拉伸试样,在热载荷和机械载荷热载荷共同作用下的蠕变性能进行数值模拟分析,得到不带微裂纹、带垂直梯度方向微裂纹和平行梯度方向微裂纹的SiC/A1FGM试样在这两种工况下的蠕变应变随坐标位置及时间变化曲线.结果发现:(1)蠕变应变主要发生在铝合金富集层,横向裂纹对试件蠕变影响不大;(2)在有机械载荷作用时,裂纹位置对最大蠕变应变值有较大影响;(3)考察紧凑拉伸试件,发现随着远离裂纹尖端,其蠕变应变值也随之迅速减小,在有机械载荷作用下,蠕变减小趋势比只受热载荷作用明显,变化趋势反映出蠕变应变与材料的应力分布有很大关系.  相似文献   

8.
凌力尔特公司(Linear Technology Corporation)推出1.5W输出的DC/DC微型模块(μModule)转换器LTM8047和LTM8048,这两款器件具有725VDC电流隔离,采用9mm×11.25mm×4.92mmBGA(球栅阵列)封装。  相似文献   

9.
核酸适体(Aptamer)是单链寡核苷酸片段,对靶分子具有高亲和力和高特异性,具有常规识别分子(如抗体和酶)所不具备的一些优点,该文基于核酸适体制备了一种用于检测腺苷的免标记电化学传感器。将腺苷的核酸适体与带巯基的捕获探针通过硫-巯键组装到金电极表面,用6-巯基己醇(MCH)作为缺陷探针封闭电极表面,得到的MCH/Aptamer-Capture/Au界面,构筑的电化学传感器对腺苷具有特异性识别功能,检测腺苷的线性范围为1×10-6mol/L~2.5×10-4mol/L,检测限为0.1μmol/L,相对标准偏差(R.S.D)为2.0%。该传感器对腺苷的检测具有灵敏度高、检测范围宽、制作简便、成本低,并且具有良好的选择性和重现性。  相似文献   

10.
纳米压痕法对304不锈钢残余应力的研究   总被引:2,自引:0,他引:2  
利用纳米压痕法研究了304不锈钢的残余应力,采用Suresh理论模型恒定载荷时的公式计算残余应力,最大加载载荷依次为500μN、1 000μN、1 500μN、2 000μN、2500μN。结果表明,不锈钢硬度和弹性模量为定值,退火前后的硬度分别为5.3GPa和4.0 GPa,弹性模量分别为110 GPa和100 GPa。利用Ansys分析软件模拟了压痕过程,发现不锈钢在受压过程中有Sink-in现象发生。纳米压痕法测得了未退火不锈钢存在残余压应力,大小为381 MPa;用XRD测得了未退火不锈钢中有350 MPa±23 MPa的残余压应力,两种测量结果吻合良好,说明了纳米压痕法在残余应力测试时的准确性与可靠性。  相似文献   

11.
为提高光刻仿真效率,通过对光刻原理进行研究,提出了2种多边形处理算法,将掩模上的多边形图案进行切分优化,将其划分成若干矩形或三角形。在Linux环境下应用C语言设计出一个完整的光刻仿真系统,设计的具体光学参数为:光源波长为193nm,数值孔径为0.3~0.8,部分相干系数可调范围为0.2~0.8,可一次性仿真1μm×1μm到10μm×10μm范围内的45 nm~0.18μm工艺的复杂版图,并通过多次实验进行验证。实验结果表明:原版图图像的边缘细节得到保留,且该算法有效地减少了光刻模拟的计算复杂度与计算时间,整体效率提升20%以上,为当前智能传感器系统芯片的制造节省了宝贵时间。  相似文献   

12.
利用旋转甩涂法(Spin-Coating)将间甲酚紫-聚乙烯吡咯烷酮复合薄膜固定在K+交换玻璃光波导表面研制了光波导敏感元件.研究了不同复合比例的间甲酚紫-聚乙烯吡咯烷酮复合薄膜与酸性和挥发性有机气体作用前后的紫外可见吸收光谱变化,并在此基础上研究了该敏感元件在光波导测试系统中对酸性和挥发性有机气体的响应.敏感薄膜与酸性气体作用后,薄膜由黄色变为紫红色.该敏感元件能检测到体积比浓度低于1×10-10(1.41×10-4 mg/m3)的H2S,响应和恢复时间分别为1.1 s和8.5 s,信噪比S/N为15.43;能检测到体积比浓度低于1×10-10(2.66×10-4 mg/m3)SO2气体,响应和恢复时间分别为0.4 s和2.7 s,信噪比S/N为5.88.间甲酚紫-聚乙烯吡咯烷酮复合薄膜厚度为199 nm±5 nm.  相似文献   

13.
制作了接枝氨基的多壁碳纳米管薄膜传感器。研究了其对低体积分数甲醛气体的温度响应特性和膜厚与响应的关系。结果表明:当温度为22℃,薄膜的厚度为8.1μm时,这种薄膜传感器对低体积分数为20×lO-9的甲醛气体的响应可以达到2.9%,此体积分数低于国际卫生组织规定的标准。  相似文献   

14.
In this paper, we have demonstrated a successful electroplating process of nickel (Ni) in a sulfamate electrolyte bath at ultra low electrolytic temperatures of 273–278 K. The potentiostatic mode is essential for the electroplating process rather than galvanostatic mode. The reason is that diffusion-limited current can be easily obtained by applying a specific potential which is higher than reduction potential. On the contrary, galvanostatic mode can not identify the diffusion-limited current and the reduction will suspend while the setting current is higher than diffusion-limited current ranged in hundreds of μA. The microstructure, morphology and hardness of the Ni electrodeposits were characterized using grazing incidence x-ray diffractometer, atomic force microscopy and nano-indentation test were performed. The hardness of Ni film was much enhanced to around 6.37 GPa at 273 K to 6.18 GPa at 278 K compared with that around 4.11 GPa at 288 K to 4.01 GPa at 293 K. The normal hardness of pure nickel is about 4 GPa. The enhanced hardness of Ni at ultra low temperature is attributed to both mechanisms of reduced grain size strengthening and residual compressive stress hardening.  相似文献   

15.
A novel silicon light emitting diode(LED) display array has been fabricated using 0.35 μm standard CMOS technology.In this array,an LED and static random access memory(SRAM) are integrated together in a special layout.The SRAM in each pixel can store the state of the pixel and ensure that the pixel remains lit without persistent flashing.As a result,the control logic is perfectly integrated on the same wafer.Two power sources are used to drive the display array because the LEDs operate at high voltage(supply voltage of 9 V),and the current of the whole display array is about 30-60 mA to display common characters.The display circuit includes digital control logic circuits and SRAM,and requires a supply voltage of 3.3 V.The area of a single pixel is 40×40 μm 2,the area of the whole 16×16 LED array is 1 mm 2,and the display density is 630 dpi.  相似文献   

16.
采用自行研制的鼓膜实验装置,结合迈克尔逊激光干涉位移测量技术,获取薄膜的变形值与压力值之间的关系曲线,以实现薄膜试样力学性能的测试.对鼓膜法测试薄膜力学性能的现状做了评述;对实验原理以及装置设计进行论述;进行实验测量,并对实验结果进行有限元分析与仿真.对纯铝薄膜(纯度99.9%,厚为210 μm)进行鼓膜实验,测得其弹性模量E为68.3 GPa,与资料结果基本一致,说明研制的鼓膜实验装置测量薄膜力学性能方法切实可行.实验装置对于在微/纳机电系统(MEMS/NEMS)中广泛应用的薄膜材料的力学性能表征具有十分重要的意义.  相似文献   

17.
采用MEMS技术设计了一种微型半填充气相色谱柱,运用深反应离子刻蚀(DRIE)技术,对器件刻蚀深250μm,其微型色谱柱总长度为1m,宽度为160μm,槽道内部填充20μm×20μm微型柱。采用静态涂覆法对色谱柱涂覆SE—54固定相。通过理论模拟分析柱结构,得出微型半填充色谱柱具有高分离效率能力。在对酯类化合物分离测试中,选取了含酯类的化学战剂模拟剂和几种酯类食品添加剂,分别对其进行分离,所有组分在75s内被完全分离。实现了微型半填充色谱柱快速并具有高分离率。  相似文献   

18.
Metal multi-user MEMS processes (MetalMUMPs) offered by MEMSCAP provide a 20 μm thick electroplated nickel film suitable for constructing micro RF tunable capacitors, RF inductors, relays, switches, etc. Currently the Young's modulus and the residual stress gradient of the MetalMUMPs nickel film have not been characterized. In this paper the resonance method is used to characterize the Young's modulus of the MetalMUMPs nickel film. The characterization results show that the nickel film has a Young's modulus of 155–164 GPa with an average of 159 GPa. A stress gradient induced free beam mechanism is proposed in this paper to characterize the residual stress gradient in the MetalMUMPs nickel film. Characterization results show that the residual stress in the electroplated nickel film has a gradient across the film thickness of −5.49 MPa/μm to −4.30 MPa/μm with the average of −4.72 MPa/μm. The residual stress change from the bottom surface to the top surface of the nickel film is −97.7 MPa. The Young's modulus and residual stress gradient of the MetalMUMPs nickel film obtained in this paper provide MetalMUMPs users an important reference for designing, optimizing and analyzing suspended nickel structures. The stress gradient induced free beam mechanism proposed in this paper provides a method of characterizing negative residual stress gradient in thin films without using trenches or through-wafer holes.  相似文献   

19.
Microbridge testing on symmetrical trilayer films   总被引:1,自引:0,他引:1  
In this paper, we extended the microbridge testing method to characterize the mechanical properties of symmetrical trilayer thin films. Theoretically, we analyzed the deformation of a trilayer microbridge sample with a deformable boundary condition and derived load-deflection formulas in closed-form. The slope of a load-deflection curve under small deformation gives the relationship between the bending stiffness and the residual force of a trilayer microbridge. Taking this relationship, we were able to assess simultaneously the Young's modulus of two kinds of materials composing the symmetrical trilayer film and the thickness-averaged residual stress of the film. Experimentally, we fabricated symmetrical trilayer microbridge samples of SiO/sub 2//Si/sub 3/N/sub 4//SiO/sub 2/ on 4-inch p-type (100) silicon wafers and conducted the microbridge tests with a load and displacement sensing nanoindenter system equipped with a microwedge indenter. The experimental results verified the proposed microbridge testing method. The thickness-averaged residual stress of the 1.1-/spl mu/m trilayer thin films was determined to be 8.8 MPa, while the Young's modulus of the 0.3-/spl mu/m silicon oxide layers and the Young's modulus of the 0.5-/spl mu/m silicon nitride layer were evaluated to be 31 GPa and 294 GPa, respectively.  相似文献   

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