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51.
Stephen Mason 《Computer Fraud & Security》2004,2004(3):6-13
Technology has long been used in the process of voting, and the use of electronic machines was introduced in the United States of America in the 1970s. More recently, vendors have encouraged the use of remote electronic voting methods, and politicians have begun to consider such options, including the use of the Internet, telephone, text messaging and interactive digital television. This paper considers some of the practical and security issues that affect remote electronic voting. 相似文献
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Results from wear studies in repetitive impact sliding are described in this paper. The material pair studied consisted of steel CPM-10V (specimen) (where CPM denotes crucible particle metallurgy) and 17-4 precipitationhardened (PH) steel (counterface) with transverse sliding velocities of 4 and 8 m s?1. By means of scanning electron microscopy, energy-dispersive analysis of X-rays and X-ray diffraction methods it is shown that the wear is due to a material transport of the counterface 17-4 PH steel to the CPM-10V surface. In the wear process, a change in microhardness of the counterface substrate is apparent, and X-ray diffraction of debris confirms the presence of transformed metal. These products include γ-Fe together with trace amounts of α-Fe2O3; however, virtually no carbide from the CPM-10V steel was detected. 相似文献
54.
Scanning electron microscope (SEM) tribometric data on polycrystalline silicon (poly-Si) vs. poly-Si, Si(100) vs. Si(100)
and Si(111) vs. Si(111) interfaces, obtained in
Torr and in 0.2 Torr partial pressure of hydrogen gas (
) from room temperature to 850°C, were performed under standard and much slower thermal ramping rates. The friction data were analyzed per the methodology
described in part I of this paper series. The results indicate a highly beneficial friction- and wear-reducing regime within
a relatively narrow thermal region. This desirable region coincides with some chemisorption of excited species of molecular
hydrogen just before the mass thermal desorption of surface hydrides. These data represent the tribochemical equivalent of
a method routinely used in electronics, whereby deep electron traps (dangling Si bonds) are passivated by baking in molecular
hydrogen. The
also exerts a moderating influence on the size of the friction noise at all test temperatures. However, the general level
of friction beyond the beneficial thermal region is high. In parallel, the general wear rate of Si representative of the entire
range of standard thermal ramping in both atmospheric environments is in the extremely high 10-12m3/(N m) range. Operating strictly in the beneficial, low-friction thermal regime resulted in a several orders-of-magnitude
reduction in the wear rate over those measured under standard thermal ramping conditions. Although the results confirm previous
findings that Si is not a good material of construction for miniaturized moving mechanical assemblies (e.g., microbearings
and gears), there seems to be some limited possibility of gas-phase lubrication of Si micromechanisms with rarefied hydrogen
at surface temperatures between 100 and 300°C.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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57.
Laura A. Arvalo Stephen A. OBrien Eneko Lopez Gajendra Pratap Singh Andreas Seifert 《International journal of molecular sciences》2022,23(12)
Vibrational spectroscopy techniques are widely used in analytical chemistry, physics and biology. The most prominent techniques are Raman and Fourier-transform infrared spectroscopy (FTIR). Combining both techniques delivers complementary information of the test sample. We present the design, construction, and calibration of a novel bimodal spectroscopy system featuring both Raman and infrared measurements simultaneously on the same sample without mutual interference. The optomechanical design provides a modular flexible system for solid and liquid samples and different configurations for Raman. As a novel feature, the Raman module can be operated off-axis for optical sectioning. The calibrated system demonstrates high sensitivity, precision, and resolution for simultaneous operation of both techniques and shows excellent calibration curves with coefficients of determination greater than 0.96. We demonstrate the ability to simultaneously measure Raman and infrared spectra of complex biological material using bovine serum albumin. The performance competes with commercial systems; moreover, it presents the additional advantage of simultaneously operating Raman and infrared techniques. To the best of our knowledge, it is the first demonstration of a combined Raman-infrared system that can analyze the same sample volume and obtain optically sectioned Raman signals. Additionally, quantitative comparison of confocality of backscattering micro-Raman and off-axis Raman was performed for the first time. 相似文献
58.
Jason K. Iles Raminta Zmuidinaite Christoph Sadee Anna Gardiner Jonathan Lacey Stephen Harding Gregg Wallis Roshani Patel Debra Roblett Jonathan Heeney Helen Baxendale Ray Kruse Iles 《International journal of molecular sciences》2022,23(11)
The involvement of immunoglobulin (Ig) G3 in the humoral immune response to SARS-CoV-2 infection has been implicated in the pathogenesis of acute respiratory distress syndrome (ARDS) in COVID-19. The exact molecular mechanism is unknown, but it is thought to involve this IgG subtype’s differential ability to fix, complement and stimulate cytokine release. We examined the binding of convalescent patient antibodies to immobilized nucleocapsids and spike proteins by matrix-assisted laser desorption/ionization–time of flight (MALDI-ToF) mass spectrometry. IgG3 was a major immunoglobulin found in all samples. Differential analysis of the spectral signatures found for the nucleocapsid versus the spike protein demonstrated that the predominant humoral immune response to the nucleocapsid was IgG3, whilst for the spike protein it was IgG1. However, the spike protein displayed a strong affinity for IgG3 itself, as it would bind from control plasma samples, as well as from those previously infected with SARS-CoV-2, similar to the way protein G binds IgG1. Furthermore, detailed spectral analysis indicated that a mass shift consistent with hyper-glycosylation or glycation was a characteristic of the IgG3 captured by the spike protein. 相似文献
59.
60.
Jung-Jae Park Min-Wook Lee Sam S. Yoon Ho-Young Kim Scott C. James Stephen D. Heister Sanjeev Chandra Woon-Ha Yoon Dong-Soo Park Jungho Ryu 《Journal of Thermal Spray Technology》2011,20(3):514-522
Characteristics of supersonic flow are examined with specific regard to nano-particle thin-film coating. Effects of shockwaves, nozzle geometry, chamber pressure, and substrate location were studied computationally. Shockwaves are minimized to reduce fluctuations in flow properties at the discontinuities across diamond shock structures. Nozzle geometry was adjusted to ensure optimal expansion (i.e., P exit = P ambient), where shock formation was significantly reduced and flow kinetic energy maximized. When the ambient pressure was reduced from 1 to 0.01316 bar, the nozzle’s diverging angle must be increased to yield the optimum condition of minimized adversed effects. Beyond some critical distance, substrate location did not seem to be a sensitive parameter on flow characteristics when P amb = 0.01316 bar; however, overly close proximity to the nozzle exit caused flow disturbances inside the nozzle, thereby adversely affecting coating gas flow. 相似文献