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101.
102.
锂离子选择性微电极在生物体液中的响应 总被引:2,自引:0,他引:2
最近几年已报道了几种锂离子选择性电极.本文作者曾研制了以苯基膦酸二辛酯(DOPP)为溶剂,四苯硼酸盐为活性物质的PVC膜锂离子选择电极.本文在此基础上研制了锂离子选择性微电极,比较了以四苯硼酸钾(KTPB)及四苯硼酸钠(NaTPB)为活性物质的锂微电极的性能.同时考察了微电极在细胞内液、血清及生理盐液中对锂离子的响应特性. 相似文献
103.
PreparationandCrystalStructureofPrNb_5O_(14)¥MaoJiang-Gao;ZhuangHong-Hui;HuangJin-Shun(StateKeyLaboratoryofStructuralChemistry... 相似文献
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A very sensitive electroanalytical method was employed to determine bergenin in phosphate buffer with a pH of 6.0, bergenin was accumulated at a 4-(2-pyridylazo)-resorcinol (PAR) polymer film modified glassy carbon electrode (GCE) surface under the condition of open-circuit. In the following anodic sweep from −0.4 to 0.8 V, bergenin adsorbed at the PAR polymer film modified electrode surface, was oxidized and yielded a sensitive oxidation peak at 0.595 V. Due to its unique structure and extraordinary properties, the PAR polymer film shows higher accumulation efficiency toward bergenin compared with a bare GCE. Hence, the amount of bergenin at the PAR polymer film modified GCE surface increases significantly, and finally the oxidation peak current improves greatly. The experimental conditions, such as supporting electrolyte, pH value, accumulation time and scan rate, were optimized for the measurement of bergenin, and a sensitive electroanalytical method was proposed for bergenin determination. The oxidation peak current varies linearly with the concentration of bergenin over the range of 2.0 × 10−7 to 1.2 × 10−5 mol/L, and the detection limit is 2.0 × 10−8 mol/L after 3 min open-circuit accumulation. The relative standard deviation of the same electrode in 10 successive scans is 1.8% for 1.0 × 10−6 mol/L bergenin and 2.1% for interelectrodes, indicating excellent reproducibility. This new method was successfully demonstrated with bergenin tablets and diluted urine. 相似文献
106.
Studyofthegrowthprocessofcolloidalparticlesofnonequilibriumandirreversibilityisanactiveareaofresearch.Therecognitionofcolloidalaggregatesasfractalobjectshasinspiredalargenumberofexperimentalandtheoreticalstudiesonthestructuralandkineticaspectsofaggregationprocesses"'.Morerecently,kineticsofhematiteaggregationbypolyacrylicacidhavebeenstudiedbyzhangandBume3.Theprimaryhematiteparticleswerequiteuniformandfairlyspherical.Inthispaper,wewillreportthesizeevolutionoffractalaggregatesofinitiallypolydis… 相似文献
107.
A simple method is developed to synthesize gram quantities of uniform Ge nanowires (GeNWs) by chemical vapor deposition on preformed, monodispersed seed particles loaded onto a high surface area silica support. Various chemical functionalization schemes are investigated to passivate the GeNW surfaces using alkanethiols and alkyl Grignard reactions. The stability of functionalization against oxidation of germanium for various alkyl chain lengths is elucidated by X-ray photoelectron spectroscopy. Among all schemes tested, long chain alkanethiols (> or = C12) are found to impart the most stable GeNW passivation against oxidation upon extended exposure to ambient air. Further, the chemically functionalized oxidation-resistant nanowires are soluble in organic solvents and can be readily assembled into close-packed Langmuir-Blodgett films potentially useful for future high performance electronic devices. 相似文献
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Ching-Yang Chen Yung-Ching Chao De-Shin Liu Zhen-Wei Zhuang 《Microelectronics Reliability》2006,46(8):1326-1334
This paper presents a chip-on-glass (COG) package solution for CMOS image sensors based on highly precise and reliable bumping and flip-chip bonding techniques. The package is fabricated using three core techniques, namely the damage-free image sensor bumping technique, the wafer form glass substrate patterned technique, and the damage-free flip-chip bonding technique. Since the proposed package concept is new, the effects of the package geometry and material properties on the package reliability are uncertain in the initial design stage. A three-dimensional nonlinear finite element model of the proposed CMOS image sensor package is created. In the simulations, the applied thermal load is cooled from 200 °C to ambient temperature (25 °C) to model the thermal deformation and warpage of the package during the practical ACF assembly cooling process. The design parameters influencing the reliability of the package, i.e. the material properties of the ACF, the thickness of the image chip and the thickness of the optical glass are investigated. Two control levels are specified for the chip, glass, and ACF factors and a 23 factorial design is created to determine the appropriate combination of material properties and geometric size. It is found that the glass thickness and the ACF properties significantly affect the thermal deformation of the package, while the chip and glass factors, and the interaction between them, significantly affect the warpage. Regression models are developed to perform a series of surface response simulations. Using the developed statistical tests and regression models, suitable material selection criteria and geometric sizes can be specified to satisfy various reliability considerations in the initial design stage. 相似文献
110.
Quality-of-service provisioning and efficient resource utilization in CDMA cellular communications 总被引:1,自引:0,他引:1
Hai Jiang Weihua Zhuang Xuemin Shen Qi Bi 《Selected Areas in Communications, IEEE Journal on》2006,24(1):4-15
One of the major challenges in supporting multimedia services over Internet protocol (IP)-based code-division multiple-access (CDMA) wireless networks is the quality-of-service (QoS) provisioning with efficient resource utilization. Compared with the circuit-switched voice service in the second-generation CDMA systems (i.e., IS-95), heterogeneous multimedia applications in future IP-based CDMA networks require more complex QoS provisioning and more sophisticated management of the scarce radio resources. This paper provides an overview of the CDMA-related QoS provisioning techniques in the avenues of packet scheduling, power allocation, and network coordination, summarizes state-of-the-art research results, and identifies further research issues. 相似文献