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91.
92.
Jesse V. Jokerst Jie Chou James P. Camp Jorge Wong Alexis Lennart Amanda A. Pollard Pierre N. Floriano Nicolaos Christodoulides Glennon W. Simmons Yanjie Zhou Mehnaaz F. Ali John T. McDevitt 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(5):612-612
The slow development of cost‐effective medical microdevices with strong analytical performance characteristics is due to a lack of selective and efficient analyte capture and signaling. The recently developed programmable nano‐bio‐chip (PNBC) is a flexible detection device with analytical behavior rivaling established macroscopic methods. The PNBC system employs ≈300 μm‐diameter bead sensors composed of agarose “nanonets” that populate a microelectromechanical support structure with integrated microfluidic elements. The beads are an efficient and selective protein‐capture medium suitable for the analysis of complex fluid samples. Microscopy and computational studies probe the 3D interior of the beads. The relative contributions that the capture and detection of moieties, analyte size, and bead porosity make to signal distribution and intensity are reported. Agarose pore sizes ranging from 45 to 620 nm are examined and those near 140 nm provide optimal transport characteristics for rapid (<15 min) tests. The system exhibits efficient (99.5%) detection of bead‐bound analyte along with low (≈2%) nonspecific immobilization of the detection probe for carcinoembryonic antigen assay. Furthermore, the role analyte dimensions play in signal distribution is explored, and enhanced methods for assay building that consider the unique features of biomarker size are offered. 相似文献
93.
Statistical studies on the reflection coefficient of concrete–glass building facades are conducted using a fast and an accurate method based on the Green’s functions. The variation of different architectural parameters, such as concrete permitting and distribution, size and type of windows, are studied. The influence of selected parameters on the total reflection coefficient of the building is quantified for different incidence and observation angles as well as in different diffraction zones. 相似文献
94.
Y. C. Lin Sheng-Li Shie Tin-En Shie Yuen-Yee Wong K. S. Chen E. Y. Chang 《Journal of Electronic Materials》2011,40(3):289-294
This study investigates electrical characteristics and the formation mechanism of the Cu/Ge/Pd Ohmic contact to n-type InGaAs. After annealing the contact at 250°C for 20 min, Cu3Ge and Pd12Ga5As2 compounds formed and Ge diffused into the InGaAs layer, achieving a heavily doped InGaAs layer with a low contact resistivity
of 1 × 10−6 Ω cm2. Thermal stability tests were performed on the Cu/Ge/Pd Ohmic contact to InGaAs after Ohmic contact formation, showing no
obvious degradation after a 72 h reliability test at 250°C. The results indicate excellent electrical characteristics and
thermal stability using Cu/Ge/Pd as an Ohmic contact metal to an n-InGaAs layer. 相似文献
95.
Strain-controlled fatigue lives of conduit polymers, viz., nylon 6, polypropylene (PP) and calcium carbonate filled black
colored polypropylene (PP-blk) were studied. Thermal and mechanical analyses were conducted before fatigue tests. Thermal
characteristics, such as the degree of molecular degradation, glass transition temperatures, and melting points were determined.
Tensile strength, elastic modulus, and Poisson’s ratio were obtained from tests under quasi-static loading. Fatigue lives
were measured under different displacement ranges and temperature conditions. Four different temperatures were selected to
represent low (−40 °C), room (25 °C), and high (65 and 125 °C) temperature conditions. Hysteretic heating was found to be
significantly operative in PP specimens. By optimizing the previously developed unified strain model [1], strain fatigue lives were predicted based on the studied materials. 相似文献
96.
The effects of crystallinity, phase and oxygen vacancies on optical and photocatalytic properties of titania (TiO2) thin films were systematically studied. The as-deposited amorphous titania films were prepared by reactive sputtering titanium metal targets in argon–oxygen plasma at 100 °C and subsequently annealed at various temperatures of 400–800 °C in air, vacuum and H2 atmosphere. The results indicate that in general the crystallinity of the annealed films is enhanced with the increasing annealing temperature. At the same temperature, the H2 annealed films achieve better crystallinity but containing more oxygen vacancies than the films annealed in air and in vacuum. In H2 or in vacuum, the concentration of oxygen vacancies in the annealed films increases with increasing temperature, while in air it remains constant. Oxygen vacancies in titania film not only facilitate phase transformation but also lower the band gap of titania, and make the film visible-light responsive. Photocatalytic properties of the TiO2 films were characterized in UV and visible light irradiation by following the Ag reduction and degradation of methylene blue. The films annealed at 600–700 °C in H2 possess the best film crystallinity and the proper concentration of oxygen vacancies and exhibit the best photocatalytic performance under both UV and visible light. 相似文献
97.
建筑工程项目施工阶段的质量控制是一项极其复杂的工作,如何做好建筑工程项目质量控制,是建筑企业发展的永远课题。文章主要就如何在建筑工程项目施工阶段进行质量控制展开讨论。 相似文献
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100.
This article presents a study on the movement of an oil entrapment (or impact dimple) in a pure rolling elastohydrodynamic
lubricated (EHL) contact. The oil entrapment was formed by impacting a steel ball against a lubricated glass disc. The contact
was then activated under pure rolling conditions, and the movement of the entrapped oil was visualized by optical interferometry.
It was found that during the movement of the dimple within the EHL contact, there exists a critical value for the displacement
of dimple core. For the displacement of the dimple core less than the critical value, the dimple moves at the entrainment
velocity and the film thickness of dimple core remains almost constant. For displacement beyond the critical value, the dimple
slows down and its depth decreases rapidly. The effects of influential factors such as speed, initial dimple depth, load,
and initial gap size were theoretically and experimentally investigated. 相似文献