排序方式: 共有60条查询结果,搜索用时 281 毫秒
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摘 要 本文通过在不同的环境介质下进行强化实验发现,在氮气和二氧化碳气氛中采用高脉冲能量强化可获得较厚的强化层,且强化层硬度明显高于空气中获得的强化层。另外二氧化碳和氮气相比,前者的强化层硬度更高些。 相似文献
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A.G. Pavelyev Y.A. Liou J. Wickert A.A. Pavelyev T. Schmidt K. Igarashi S.S. Matyugov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
A method is introduced to locate the layered structures in the atmosphere and ionosphere based on simultaneous observations of radio wave intensity and phase variations in trans-ionospheric satellite-to-satellite links. The method determines location of a tangent point on the trans-ionospheric ray trajectory where gradient of refractivity is perpendicular to the ray trajectory and influence of a layered structure on radio wave parameters is maximal. An estimate of the location of a layer can be obtained from a combination of the phase and intensity variations. This new technique was applied to measurements provided during FORMOSAT-3 and CHAMP radio occultation (RO) missions. For the considered RO events the location of the inclined plasma layer in the lower ionosphere is found and the electron density distribution is retrieved. The method is checked by measuring the location of the tangent point on the ray trajectory in the neutral gas in the atmosphere. The results showed a fairly good agreement. 相似文献
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Navdeep Sharma Aman Mahajan 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
In this paper, the design of an orbital space settlement named Lakshita located at L5 for 10,000 residents having area of 1 × 106 m2 has been proposed, with the aim of fulfilling mining activities and space research in micro – g. All calculations are made in the perspective of a dynamic demography which could lead to the doubling of the population in next 25 years with initial population of 4500. The settlement consists of one residential torus, one agricultural torus, industrial cylinder and two docking cylinders rotating coaxially at 1 rpm. 2.3% of the total volume of settlement is provided for two docking cylinders with 6 docking ports enabling the elastic flow of space traffic, thereby providing continuous loading and unloading of cargo and passengers. Four pressurized sliding cylinders with 5.7 × 105 m3 volume above the down surface area moving along the spokes fulfill the need of adaptation of visitors at half the gravity level of primary settlement volumes, as well provide wobble control. 1.1 × 105 torr of pressure is provided above the down surface area of the residential torus. The power generation of 400 Mw, required for the functional need of Lakshita, will be obtained through SPS located at L4. The 14 h day and 10 h night cycle will be maintained by four mirrors attached on either side from the central cylinder. The walls of the settlement will be made up of three consecutive layers of super adobe, Nextel and Kevler-49 respectively to provide radiation and debris protection. An assortment of various facilities like appropriate distribution and management of water through an intended network of pipelines, accurate management of waste within the settlement has been provided. 相似文献
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Graham E. Dorrington 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
Vertical trajectory data from the VEGA 1 and 2 balloon flights in the atmosphere of Venus is re-analyzed. A previously employed helium leak rate profile invoked to entirely account for the decrease in equilibrium float altitude of VEGA 2 is questioned and deemed ad hoc. As an alternative, it is proposed that both VEGA 1 and 2 experienced in-flight mass increases due to the deposition of cloud particles onto their envelopes, as well as losing helium at a reduced rate consistent with the pre-flight prediction. Particle deposition rates are estimated and found to be compatible with this alternative scenario. Possible evidence for drizzle is also presented. Preliminary experiments to derive aerosol deposition rate on a flat plate and the maximum feasible liquid mass that may be accumulated on a near-spherical envelope are briefly described. Further experimental work is recommended to constrain the deposition efficiency values involved and the maximum feasible drizzle fluxes that could have been encountered by both VEGA 1 and 2. 相似文献
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A.A. Berezhnoy E.A. Kozlova M.P. Sinitsyn A.A. Shangaraev V.V. Shevchenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2012
Temperature regime at the LCROSS impact site is studied. All detected species in the Cabeus crater as well as CH4 and CO clathrate hydrates except H2, CO, and CH4 are stable against evaporation at the LCROSS impact site. CO and CH4 can be chemisorbed at the surface of the regolith particles and exist in the form of clathrate hydrates in the lunar cold traps. Flux rates of delivery of volatile species by asteroids, micrometeoroids, O-rich, C-rich, and low-speed comets into the permanently shadowed regions are estimated. Significant amounts of H2O, CO, H2, H2S, SO2, and CO2 can be impact-produced during collisions between asteroids and O-rich comets with the Moon while CH3OH, NH3 and complex organic species survive during low-speed comet impacts as products of disequilibrium processes. C-rich comets are main sources of CH4, and C2H4. 相似文献
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刘飞舟 《西安航空技术高等专科学校学报》2007,25(5):50-51,61
对涂装污染物的种类、成分和性质进行了分析,重点介绍了针对涂装废气的水幕净化法、高温燃烧法、吸收荆吸收和高效吸附剂吸附等处理技术;针对废水的脱脂废液酸化破乳处理、废酸液的中和处理、电泳废液的混凝剂处理和喷漆废水的试剂预处理及混凝沉淀等,这些方法科学、先进,具有较强的实用性和可操作性。 相似文献
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空气中一甲肼监测的固体吸附/分光光度法 总被引:1,自引:0,他引:1
研究了用固体吸附和分光光度监测空气中一甲肼浓度的方法,试验了标准气、采样管、比色酸度范围、温度、光强和干扰气对测试结果的影响。结果表明:以研制成的固体采样管富集采样,用对二甲氨基苯甲醛作显色剂,在470nm波长,2cm光径的比色皿,采集100L气样时,方法最低检出浓度为0.0031mg/m3,平均变异系数0.036,平均相对误差5.5%,测量范围为0.010mg/m3~2.50mg/m3。 相似文献
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《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2023,71(1):1198-1215
The Venus Express Radio Science Experiment (VeRa) was part of the scientific payload of the Venus Express (VEX) spacecraft and was targeted at the investigation of Venus’ atmosphere, surface, and gravity field as well as the interplanetary medium. This paper describes the methods and the required calibrations applied to VEX-VeRa raw radio occultation data used to retrieve vertical profiles of Venus’ ionosphere and neutral atmosphere. In this work we perform an independent analysis of a set of 25 VEX, single-frequency (X-band), occultations carried out in 2014, recorded in open-loop at the NASA Deep Space Network. Our temperature, pressure and electron density vertical profiles are in agreement with previous studies available in the literature. Furthermore, our analysis shows that Venus’ ionosphere is more influenced by the day/night condition than the latitude variations, while the neutral atmosphere experiences the opposite. Our scientific interpretation of these results is based on two major responsible effects: Venus’ high thermal inertia and the zonal winds. Their presence within Venus’ neutral atmosphere determine why in these regions a latitude dependence is predominant on the day/night condition. On the contrary, at higher altitudes the two aforementioned effects are less important or null, and Venus’ ionosphere shows higher electron density peaks in the probed day-time occultations, regardless of the latitude. 相似文献