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991.
992.
J. A. Murphy E. Gleeson G. Cahill W. Lanigan C. O’Sullivan E. Cartwright S. E. Church J. Hinderks E. Kirby K. Thompson B. Rusholme W. K. Gear B. Maffei P. A. R. Ade C. Tucker B. Jones 《Journal of Infrared, Millimeter and Terahertz Waves》2005,26(4):505-523
In this paper we report on the design and validation process for the profiled corrugated horn antennas, which feed the bolometer array of a cosmology experiment known as QUaD located at the South Pole. This is a cosmic background radiation polarization project, which demands precise knowledge and control of the optical coupling to the signal in order to map the feeble E- and B-polarization mode structure. The system will operate in two millimeter wavelength bands at 100 and 150 GHz. The imaging horn array collects the incoming signal via on-axis front-end optics and a Cassegrain telescope, with a cold stop in front of the array to terminate side-lobe structure at an edge taper of ?20dB. The corrugated horn design process was undertaken using in-house analytical software tools, based on modal scattering, specially developed for millimeter -wave profiled horn antennas. An important part of the instrument development was the validation of the horn design, in particular to verify low edge taper levels and the required well-defined band edges. Suitable feed horn designs were measured and were found to be in excellent agreement with theoretical predictions. 相似文献
993.
994.
Research on the Relationship Between Verbal and Nonverbal Communication: Emerging Integrations 总被引:1,自引:0,他引:1
The authors argue for an integrated approach in which verbal and nonverbal messages are studied as inseparable phenomena when they occur together. Addressed are assumptions of various forms of this type of research, potential relationships of quantitative and qualitative studies, current trends found in the investigations included in this special issue, and recommendations for further work. 相似文献
995.
Jacob L. Jones James M. LeBeau Jason Nikkel Adedapo A. Oni J. Houston Dycus Clayton Cozzan Fang‐Yin Lin Aleksandr Chernatynskiy Juan C. Nino Susan B. Sinnott Sungwook Mhin Geoff L. Brennecka Jon Ihlefeld 《Advanced Materials Interfaces》2015,2(10)
Understanding interfaces between dissimilar materials is crucial to the development of modern technologies, for example, semiconductor–dielectric and thermoelectric–semiconductor interfaces in emerging electronic devices. However, the structural characterization of buried interfaces is challenging because many measurement techniques are surface sensitive by design. When interested in interface evolution during synthesis, the experimental challenges multiply and often necessitate in situ techniques. For solution‐derived lead zirconate titanate (PZT) ferroelectric thin films, the evolution of buried interfaces during synthesis (including dielectric–metal and metal–metal) is thought to dramatically influence the resultant dielectric and ferroelectric properties. In the present work, multiple experimental and computational methods are combined to characterize interface evolution during synthesis of ferroelectric PZT films on platinized Si wafers—including in situ X‐ray diffraction during thermal treatment, aberration‐corrected scanning transmission electron microscopy of samples quenched from various synthesis states, and calculations using density functional theory. Substantial interactions at buried interfaces in the PZT/Pt/Ti/SiO x /Si heterostructure are observed and discussed relative to their role(s) in the synthesis process. The results prove that perovskite PZT nucleates directly from the platinum (111)‐oriented bottom electrode and reveal the roles of Pb and O diffusion and intermetallic Pt3Pb and Pt3Ti phases. 相似文献
996.
Feng Lin Dennis Nordlund Tsu‐Chien Weng Rob G. Moore Dane T. Gillaspie Kim M. Jones Anne C. Dillon Ryan M. Richards Chaiwat Engtrakul 《Advanced Materials Interfaces》2015,2(6)
Interface engineering has attracted great interest and is essential for the fabrication of thin‐film devices, such as smart windows. In this study, a solid‐state conversion reaction for the development of an interlayer enriched with lithium peroxide (Li2O2) is presented for an electrochromic device. We demonstrate that efficient lithium insertion and electron transport can be achieved by the inclusion of a Li2O2‐rich interlayer between an active electrochromic material and Li ion solid‐state electrolyte layer. The presence of a Li2O2‐rich interlayer enhances electrochromic efficiency, kinetics, optical contrast, and bleached‐state transparency in a nickel oxide‐based electrochromic thin film. This work opens up new opportunities to enhance the functionalities of thin‐film devices by solid‐state conversion reactions. 相似文献
997.
Sin Hang Lee Jessica S. Vigliotti Veronica S. Vigliotti William Jones David M. Shearer 《International journal of molecular sciences》2014,15(3):4284-4298
The diagnoses of Lyme disease based on clinical manifestations, serological findings and detection of infectious agents often contradict each other. We tested 52 blind-coded serum samples, including 20 pre-treatment and 12 post-treatment sera from clinically suspect Lyme disease patients, for the presence of residual Lyme disease infectious agents, using nested PCR amplification of a signature segment of the borrelial 16S ribosomal RNA gene for detection and direct DNA sequencing of the PCR amplicon for molecular validation. These archived sera were split from the samples drawn for the 2-tier serology tests performed by a CDC-approved laboratory, and are used as reference materials for evaluating new diagnostic reagents. Of the 12 post-treatment serum samples, we found DNA evidence of a novel borrelia of uncertain significance in one, which was also positive for the 2-tier serology test. The rest of the post-treatment sera and all 20 control sera were PCR-negative. Of the 20 pre-treatment sera from clinically suspect early Lyme disease patients, we found Borrelia miyamotoi in one which was 2-tier serology-negative, and a Borrelia burgdorferi in two—one negative and one positive for 2-tier serology. We conclude that a sensitive and reliable DNA-based test is needed to support the diagnosis of Lyme disease and Lyme disease-like borreliosis. 相似文献
998.
Kristiina Laine Kristoffer Segerholm Magnus Wålinder Lauri Rautkari Graham Ormondroyd Mark Hughes Dennis Jones 《Journal of Materials Science》2014,49(5):2027-2034
Scots pine (Pinus sylvestris L.) wood was surface densified in its radial direction in an open press with one heated plate to obtain a higher density on the wood surface whilst retaining the overall thickness of the sample. This study investigated the effect of temperature (100, 150 and 200 °C) and press closing speed (5, 10 and 30 mm/min, giving closing times of 60, 30 and 10 s, respectively) on the micromorphology of the cell-wall, as well as changes occurring during set-recovery of the densified wood. The micromorphology was analysed using scanning electron microscopy (SEM) combined with a sample preparation technique based on ultraviolet-excimer laser ablation. Furthermore, the density profiles of the samples were measured. Low press temperature (100 °C) and short closing time (10 s) resulted in more deformation through the whole thickness, whilst increasing the temperature (150 and 200 °C) and prolonging the closing time (30 and 60 s) enabled more targeted deformation closer to the heated plate. The deformation occurred in the earlywood regions as curling and twisting of the radial cell-walls, however, no apparent cell-wall disruption or internal fracture was observed, even at low temperatures and fast press closing speed, nor after soaking and drying of the samples. In the SEM-analysis after soaking and drying, it was noticed that the cells did not completely recover their original form. Thus, part of the deformation was considered permanent perhaps due to viscoelastic flow and plastic deformation of the cell-wall components. 相似文献
999.
C. M. Groh M. E. Hubbard P. F. Jones P. M. Loadman N. Periasamy B. D. Sleeman S. W. Smye C. J. Twelves R. M. Phillips 《Journal of the Royal Society Interface》2014,11(94)
The ability to predict how far a drug will penetrate into the tumour microenvironment within its pharmacokinetic (PK) lifespan would provide valuable information about therapeutic response. As the PK profile is directly related to the route and schedule of drug administration, an in silico tool that can predict the drug administration schedule that results in optimal drug delivery to tumours would streamline clinical trial design. This paper investigates the application of mathematical and computational modelling techniques to help improve our understanding of the fundamental mechanisms underlying drug delivery, and compares the performance of a simple model with more complex approaches. Three models of drug transport are developed, all based on the same drug binding model and parametrized by bespoke in vitro experiments. Their predictions, compared for a ‘tumour cord’ geometry, are qualitatively and quantitatively similar. We assess the effect of varying the PK profile of the supplied drug, and the binding affinity of the drug to tumour cells, on the concentration of drug reaching cells and the accumulated exposure of cells to drug at arbitrary distances from a supplying blood vessel. This is a contribution towards developing a useful drug transport modelling tool for informing strategies for the treatment of tumour cells which are ‘pharmacokinetically resistant’ to chemotherapeutic strategies. 相似文献
1000.
The combustion reactivity of rice husk from New South Wales,ustralia was measured by heating cubical baskets in controlled environment and monitoring the centre temperature.Frank-Kamenetskii‘s ignition theory was used to calculate the activation energy,Results agreed well with tests on other cellulosic materials,Numerical simulations of temperature changes were carried out,using a special technique to deal with non-linearities in the heat conduction equation.The numerical Results indicate that the time factor should be taken into account when evaluating self-combustion risks. 相似文献