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11.
Reactive ion etching of Ta36Si14N50 diffusion barrier layers was performed in CHF3+O2 plasmas. Etch depths and rates were determined as a function of etch gas composition, cathode power, and etching time. Etching proceeds only after an initial delay which depends on gas composition and cathode power. This delay is attributed to the presence of a native surface oxide which must first be removed before etching can commence. Maximum etch rate was attained at 62.5% O2 concentration, which also corresponds to minimum delay  相似文献   
12.
Librarians, like most professionals, may arrive at a stage in their careers when they start questioning themselves about their job satisfaction and importance. The reasons are many, from not being challenged by their work to abrupt changes in the workplace dictated by management and the economy. At this stage, professionals may begin to feel unappreciated by management and not in control of their work environment. In this piece, I offer some suggestions that could help mid-career librarians to re-energize themselves and survive in a workplace that is in constant flux. How you react to the anxiety of "job disconnect" will affect the rest of your career life. Should you become more proactive at your job, increasing your responsibility and value to your institution? What does your personality have to do with how you adjust to management changes? Does tenure fit into this equation? Should you even think about changing your job at this stage of your career? What other factors could "spice" up your career? Specific strategies and options for each of these questions will be discussed.  相似文献   
13.
The effect of spherical projectile speed in ricochet off water and sand   总被引:1,自引:0,他引:1  
Experimental results are reported for the ricochet of steel and duralumin spheres ( and 1 in. dia.), from shallow depths of water and dry sand. The critical angle for ricochet off water is shown to increase with speed to approach the theoretical limit of . For ricochet off sand the critical angle decreases with speed but a cut-off angle exists, , for which no ricochet occurs at any speed.  相似文献   
14.
Grooved-dielectric, phase-correcting, Fresnel zone plate antennas are analyzed using the body-of-revolution finite-difference time-domain (BOR-FDTD) method. Parametric studies of the focusing ability of these antennas are performed to examine the effects of the focal length, diameter, number of zones, and the thickness of the lens, as well as the number of phase corrections per zone. The results of these studies are presented as design graphs and are used to lend insight into the focusing mechanism of phase-correcting zone plates. The BOR-FDTD analysis is validated by comparison with previous measurements.  相似文献   
15.
在过去两年中,PWB的无铅制程已有稳定变化,无铅影响力在PWB设计、制造及组装过程中日趋重要。有越来越多的高密度互连应力产品,多是用一般易取得的材料制造,HDI产品逐渐增加,组装时常用的材料现在已经经由热循环测试来评估其信赖性,接着使材料通过多次高温无铅制程及重工的测试。  相似文献   
16.
Postoperative infection and thromboembolism represent significant sources of morbidity and mortality but cannot be easily tracked after hospital discharge. Therefore, a molecular test that could be performed at home would significantly impact disease management. The laboratory has previously developed intravenously delivered “synthetic biomarkers” that respond to dysregulated proteases to produce a urinary signal. These assays, however, have been limited to chronic diseases or acute diseases initiated at the time of diagnostic administration. Here, a subcutaneously administered sustained‐release system, using small poly(ethylene glycol) scaffolds (<10 nm) to promote diffusion into the bloodstream over a day, is formulated. The utility of a thrombin sensor to identify thrombosis and an Matrix metalloproteinase (MMP) sensor to measure inflammation is demonstrated. Finally, a companion paper ELISA (Enzyme‐linked immunosorbent sssay), using printed wax barriers, with nanomolar sensitivity for urinary reporters for point‐of‐care detection is developed. The approach for subcutaneous delivery of nanosensors combined with urinary paper analysis may enable facile monitoring of at‐risk patients.  相似文献   
17.
Patterned bandpass dielectric interference filters with centre wavelengths around 1.3 mu m have been applied to top-entry photodiodes to produce high-speed, high-responsivity, photodetectors for wavelength division multiplexing. The measured responsivity exceeded 25 A/W with a full width half maximum of 19 nm and peak rejection of over 25 dB.<>  相似文献   
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19.
Twenty-four patients hospitalized for overdose of a tricyclic antidepressant were monitored clinically, and serial plasma-drug measurements were taken for up to 144 hours. Six of 24 patients had maximum antidepressant plasma levels greater than or equal to 1,000 ng/ml, and their plasma levels at 96 hours ranged from 170 to 1,280 ng/ml. Patients ingesting substantial tricyclic overdoses may remain medically unstable for days. When high tricyclic levels persist, accurate psychiatric assessment is often impossible.  相似文献   
20.
Coffee and its most important constituent, caffeine, may not only stimulate the function of many organs but also increase the metabolism in the body. These effects require a higher energy production which is mainly obtained from striated muscles by glycogenolysis and from fat tissue by lipolysis. Sutherland and Butcher were able to demonstrate that these degradation processes are primarily caused by an increase of cyclic 3,5-AMP. - In this connection caffeine and other methylxanthines are of special interest because these compounds also increase the intracellular amount of cyclic 3,5-AMP. This effect may be caused by an inhibition of phosphodiesterase, a release of catecholamines with resulting stimulation of adenylcyclase or by competitive inhibition of adenosine. At the present time it cannot be said which of these mechanisms primarily is involved in the in vivo effects of caffeine and other methylxanthines.  相似文献   
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