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排序方式： 共有1147条查询结果，搜索用时 15 毫秒
1.
InGaAs近红外相机电路设计与实现 总被引：1，自引：0，他引：1
随着国外0.9～1.7μm InGaAs近红外相机的迅速发展,目前已被大量应用于工业和军事领域。探讨了InGaAs近红外相机在不同领域的应用,分析了InGaAs材料的优势及探测器选型。结合相应的探测器阵列,从相机偏置电压产生、时序驱动设计与制冷控制等方面给出了InGaAs近红外相机的硬件电路设计方案,解决了研制过程中的部分重难点,并针对后期图像处理进行了仿真验证,达到应用要求。 相似文献
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文章依据OLED器件的结构和发光机理介绍了OLED的驱动电路,并讨论了各种驱动电路在使用中的一些问题,提出了它们的适用场合. 相似文献
5.
基于视觉信息融合的驾驶员疲劳监测方法综述 总被引：2，自引：0，他引：2
驾驶疲劳已成为引发交通事故的主要原因,现介绍了疲劳产生的原因以及国内外对于疲劳状态监测技术的研究现状.详细分析了基于视觉信息的五种监测技术,认为没有一种单独的方法能够准确可靠地测量驾驶疲劳,提出了一种基于视觉信息融合的监测方法. 相似文献
6.
Dr. Tao Yang Prof. Yan Song Dr. Xiaodong Tian Prof. Huaihe Song Prof. Zhanjun Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(69):16514-16520
Pitch has been used to prepare electrodes by high-temperature heat treatments for supercapacitors, lithium-ion batteries, on account of its rich aromatic ring structure. Here, the toluene-soluble component of pitch is used to prepare a kind of laminated carbon. This was realized by a template-free synthesis at low temperature with the addition of pressure. The toluene-soluble component has a small molecular weight, which makes the thermal deformation ability stronger and then enhances the orientation of the carbon layer with the help of pressure. The prepared anode exhibits a splendid electrochemical performance compared with the traditional graphite anode. A high stable capacity of approximately 550 mAh g−1 at 50 mA g−1, which is much higher than graphite (372 mAh g−1), is obtained. Also, when the current density is up to 2 A g−1, the capacity is about 150 mAh g−1. Surprisingly, it also delivers a superior cycling performance. And when used as the anode/cathode electrode for lithium-ion capacitors, a high energy density can be obtained. The present work offers an opportunity to utilize the pitch source in lithium energy storage with promising cycle life, high energy/power density, and low cost. 相似文献
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Anbrah E. Alzubidi Prof. Alan M. Bond Assoc. Prof. Lisandra L. Martin 《Chemphyschem》2023,24(20):e202300289
Mechanistic variation in catalysis through substituent-based redox tuning is well established. Fluorination of TCNQ (TCNQ=tetracyanoquinodimethane) provides ~850 mV variation in the redox potentials of the and (n=0, 2, 4) processes. With , catalysis of the kinetically very slow ferrocyanide-thiosulfate redox reaction in aqueous solution occurs via a mechanism in which the catalyst is reduced to when reacting with which is oxidised to . Subsequently, reacts with to form and reform the catalyst, in another thermodynamically favoured process. An analogous mechanism applies with as a catalyst. In contrast, since the reaction of with is thermodynamically unfavourable, an alternative mechanism is required to explain the catalytic activity observed in this non-fluorinated system. Here, upon addition of , reduction of to occurs with concomitant oxidation of to , which then acts as the catalyst for oxidation. Thermodynamic data explain the observed differences in the catalytic mechanisms. (n=0, 4) also act as catalysts for the ferricyanide-thiosulfate reaction in aqueous solution. The present study shows that homogeneous pathways are available following addition of these dissolved materials. Previously, these (n=0, 4) coordination polymers have been regarded as insoluble in water and proposed as heterogeneous catalysts for the ferricyanide-thiosulfate reaction. Details and mechanistic differences were established using UV-visible spectrophotometry and cyclic voltammetry. 相似文献
9.
Maurer HH 《Analytical and bioanalytical chemistry》2009,393(1):97-107
Driving under the influence of prescribed or illegal drugs increases the risk of having road accidents, just like driving
under the influence of alcohol. In forensic toxicology, an increasing number of blood samples must be analyzed for drugs.
Immunoassays tailored for a limited number of drugs (of abuse) are usually applied as prescreening tests at the roadside and/or
in the laboratory. However, many other common drugs, such as anesthetics, antidepressants, antiepileptics, antihistamines,
newer designer drugs, herbal drugs, neuroleptics (antipsychotics), opioids, or sedative-hypnotics, can also impair drivers.
Therefore, this paper reviews multianalyte single-stage and tandem gas or liquid chromatography–mass spectrometry (GC-MS or
LC-MS) procedures for the screening, identification, and validated quantification of such drugs in blood that have been reported
since 2003. Basic information about the biosample assayed, workup, chromatography, the mass spectral detection mode, and validation
data is summarized in tables. The pros and cons of the reviewed procedures are critically discussed, particularly with respect
to their probable usefulness in impaired driving toxicology.
Parts of this review were presented as a plenary lecture at T2007, the joint meeting of the International Council on Alcohol,
Drugs, and Traffic Safety (ICADTS) and The International Association of Forensic Toxicologists (TIAFT), Seattle (WA), August
26–30, 2007. 相似文献
10.
J.R. Cho H.W. Lee J.S. Sohn G.J. Kim J.S. Woo 《European Journal of Mechanics - A/Solids》2006,25(6):914-926
Hydroplaning characteristics of patterned tire on wet road are investigated by making use of finite volume and finite element methods. A detailed 3-D patterned tire model is constructed by our in-house modeling program and the rainwater flow is considered as incompressible and inviscid. Meanwhile, the fluid–structure interaction between the highly complicated tire tread and the rainwater flow is effectively treated by the general coupling method. Through the numerical experiments, the rainwater flow drained through tire grooves, hydrodynamic pressure and contact force are investigated and compared with those of the three-grooved tire model. 相似文献