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1.
The hierarchical porous N/O co-functionalized carbon(HPNOC)was scalably prepared by using the lowcost and renewable blighted grains as the raw material coupled with mild KHCO_3 activation for electrochemical capacitors(ECs).The elemental N was in situ doped in the obtained HPNOC without any N-containing additives.Remarkably,the obtained HPNOC was endowed with a large specific surface area(about 2 624m~2·g~(-1)),high pore volume(about 1.35cm~3·g~(-1)),as well as high-content N/O functionalization(about 1.9%(in atom)N and about 10.2%(in atom)O.Furthermore,the as-resulted HPNOC electrode with a high mass loading of 5mg·cm~(-2 )exhibited competitive gravimetric capacitances of about 373.6F·g~(-1 )at 0.5A·g~(-1),and even about 260.4F·g~(-1 )at a high rate of 10A·g~(-1);superior capacitance retention of about 98.8%at 1A·g~(-1 )over 10 000consecutive cycles;and high specific energy of about 9.6W·h·kg~(-1 )at a power of 500W·kg~(-1),when evaluated as a promising electrode in 6mol KOH for advanced electrochemical supercapacitors.More encouragingly,the green synthetic strategy we developed holds a huge promise in generalizing for other biomass-derived carbon materials for versatile energy-related applications. 相似文献
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3.
E. R. Muslimov E. Hugot M. Ferrari T. Behaghel N. K. Pavlycheva 《Russian Aeronautics (Iz VUZ)》2018,61(1):1-7
The possibility of constructing an optical scheme of a telescope for a small satellite based on mirrors with freeform surfaces and a curved photodetector is considered. It is shown that the use of a new element base allows the effective area of the main mirror to be maximized and the field of view up to 9.4 times to be increased in comparison with the classical scheme of the Ritchey–Chretien scheme in ensuring the high image quality. 相似文献
5.
L O Bjorn S Widell T Wang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2002,30(6):1557-1562
Plants have evolved under the influence of UV-B radiation and have acquired systems for monitoring it and investing appropriate resources for protection against it, i.e., filters, quenchers of radicals and reactive oxygen species, and repair systems. An hypothesis for how plants monitor radiation has been presented. 相似文献
6.
晶体管h参数微变等效电路是电子技术中求解低频、小信号放大电路常用的分析方法.本文通过具体分析,将模拟放大电路进行了新的分类,并且明确而系统地给出运用微变等效电路求解各类模拟放大电路动态指标Av、ri和γ0公式、解题难点及规律. 相似文献
7.
Snyder S. Schipper B. Vallot L. Parker N. Spitzer C. 《Aerospace and Electronic Systems Magazine, IEEE》1992,7(5):3-11
In November 1990, a differential GPS/inertial flight test was conducted to acquire a system performance database and demonstrate automatic landing using an integrated differential GPS/INS with barometric and radar altimeters. Flight test results obtained from postflight data analysis are presented. These results include characteristics of DGPS/inertial error, using a laser tracker as a reference. In addition, data are provided on the magnitude of the differential correlations and vertical channel performance with and without radar altimeter augmentation. Flight test results show one sigma DGPS/inertial horizontal errors of 9 ft and one sigma DGPS inertial vertical errors of 15 ft. Without selective availability effects, the differential corrections are less than 10 ft and are dominated by receiver unique errors over the time period of an approach. Therefore, the one sigma performance of the autonomous GPS (8-ft horizontal and 20-ft vertical) is very similar to the DGPS/inertial performance. Postprocessed results also demonstrate significant improvements in vertical channel performance when GPS/inertial is aided with radar altimeter along with a low-resolution terrain map 相似文献
8.
T Berger M Hajek L Summerer N Vana Y Akatov V Shurshakov V Arkhangelsky 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2004,34(6):1414-1419
The Atominstitute of the Austrian Universities has conducted various space research missions in the last 12 years in cooperation with the Institute for Biomedical Problems in Moscow. They dealt with the exact determination of the radiation hazards for cosmonauts and the development of precise measurement devices. Special emphasis will be laid on the last experiment on space station MIR the goal of which was the determination of the depth distribution of absorbed dose and dose equivalent in a water filled Phantom. The first results from dose measurements onboard the International Space Station (ISS) will also be discussed. The spherical Phantom with a diameter of 35 cm was developed at the Institute for Biomedical Problems and had 4 channels where dosimeters can be exposed in different depths. The exposure period covered the timeframe from May 1997 to February 1999. Thermoluminescent dosimeters (TLDs) were exposed inside the Phantom, either parallel or perpendicular to the hull of the spacecraft. For the evaluation of the linear energy transfer (LET), the high temperature ratio (HTR) method was applied. Based on this method a mean quality factor and, subsequently, the dose equivalent is calculated according to the Q(LET infinity) relationship proposed in ICRP 26. An increased contribution of neutrons could be detected inside the Phantom. However the total dose equivalent did not increase over the depth of the Phantom. As the first Austrian measurements on the ISS dosimeter packages were exposed for 248 days, starting in February 2001 at six different locations onboard the ISS. The Austrian dosimeter sets for this first exposure on the ISS contained five different kinds of passive thermoluminescent dosimeters. First results showed a position dependent absorbed dose rate at the ISS. 相似文献
9.
论述了我国加入世界贸易组织后,如何搞好航空产品的包装和包装标准化工作,以提高航空工业军品和民品在国际市场的竞争能力。 相似文献
10.
王宜龙 《航空精密制造技术》2002,38(1):38-40
对污水处理装置的技术参数、技术要求及设计方案的选择、工作原理做了进一步的阐述。对工业循环冷却水的处理有实际指导意义。 相似文献