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新型电磁式孔底冲击器工作机理研究 总被引：4，自引：0，他引：4
冲击回转钻进是一种提高硬岩钻探效率的有效方法,实现冲击回转钻进的关键设备是冲击器。针对现有液动、风动冲击器在应用中存在的不足,提出了利用可充电电池组为动力的新型电磁式孔底冲击器的设计思路。详细介绍了新型电磁式孔底冲击器的结构和工作原理,对冲击器的控制系统、电磁驱动部分及电池组供电方案等关键设计技术进行了阐述。研究表明,新型电磁式孔底冲击器能够克服液动、风动冲击器的众多不足、优点显著,具有广泛的推广应用前景。 相似文献
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The Seasonal Variabilities in the Concentration of Atmospheric Aerosols over Qingdao, China 总被引：2，自引：0，他引：2
SHENG Lifang FU Ying QIU Mingyan GAO Huiwang 《中国海洋大学学报(英文版)》2005,4(4):383-390
Mass concentrations of Total Suspended Particles （TSP） and size-segregated particles were obtained from July 2001 to June 2002 in Qingdao to characterize the seasonal variations of atmospheric aerosols and to show the impact of dust events on the air quality in Qingdao. Data on size-segregated aerosols show that 73.74% of the TSP mass concentration is contributed by particles with diameters less than 11 μm. Particles with diameters less than 1.1μm have a higher concentration during the winter. In spring, larger particles tend to have higher mass concentrations. Bimodal particle size distributions have been observed, with maxima around 4.7-7 μand 0.43-0.65 μm in the winter season, and 7-11 μm and 0.65-1.1 μm in the autumn season. Measurements made during the dust events in March 2002 show high concentrations of particles in the size range 2.1-7μm. 相似文献
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充分认识外太阳系撞击体的来源类型和分布特征,对认识外太阳系固态天体上撞击过程,明确外太阳系天体上的撞击坑生成率和撞击坑定年等诸多方面具有重要的意义.得益于海量高质量探测数据的获取,如今我们对内太阳系主要天体表面的撞击分布和来源已经有了较为深入的了解,但对外太阳系天体的撞击分布和来源还知之甚少.不同大小频率的撞击体会在外太阳系冰卫星表面形成不同大小频率分布的撞击坑,不同飞行速度的撞击体也会在同步自转的冰卫星上留下程度不同的前导-后随半球不对称分布的撞击坑,因此,对外太阳系冰卫星上撞击坑的大小频率分布和前导-后随半球不对称性分布的观测,可以用于反推外太阳系的主要撞击来源.木星系统中大坑(D＞10～30 km)的主要撞击来源是日心小天体(环绕太阳),但目前在木卫三和木卫四上观测到的前导-后随半球不对称性程度与黄道彗星引起的不对称性程度并不相符,更接近于近各向同性彗星(NICs)引起的不对称性,这与目前的天文观测和理论计算结果不一致;木卫二上的大坑稀少,小坑(D＜1 km)则主要受一次坑的溅射物影响.对土星系统,土卫五和土卫八的大坑(D＞20～30 km)分布更符合日心小天体来源;而土卫一、土卫四、土卫三上的分布则与行心碎屑物(以行星为中心)一致,尤其是小坑更可能来自以土星为中心的撞击体影响,例如大型盆地的溅射物或卫星碎片残骸. 相似文献
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简要说明液动冲击回转钻进是一项投资少,见效快的先进适用的钻探技术,可大幅度提高钻探效率和经济效益,增加回次长度和岩矿芯采取率,并能减少孔内事故。 相似文献
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T. A. Mather A. G. Allen C. Oppenheimer D. M. Pyle A. J. S. McGonigle 《Journal of Atmospheric Chemistry》2003,46(3):207-237
We present the first application of a multi-stage impactor to study volcanic particle emissions to the troposphere from Masaya volcano, Nicaragua. Concentrations of soluble SO4
2–,Cl–, F–, NO3
–, K+, Na+,NH4
+, Ca2+ and Mg2+ were determined in 11 size bins from 0.07 m to >25.5 m. The near-source size distributions showed major modes at 0.5m (SO4
2–, H+,NH4
+); 0.2 m and 5.0 m (Cl–) and 2.0–5.0 m(F–). K+ and Na+ mirrored the SO4
2– size-resolvedconcentrations closely, suggesting that these were transported primarily asK2SO4 and Na2SO4 in acidic solution, while Mg2+ andCa2+ presented modes in both <1 m and >1 m particles. Changes in relative humidity were studied by comparing daytime (transparent plume) and night-time (condensed plume) results. Enhanced particle growth rates were observed in the night-time plume as well as preferential scavenging of soluble gases, such as HCl, by condensed water. Neutralisation of the acidic aerosol by background ammonia was observed at the crater rim and to a greater extent approximately 15 km downwind of the active crater. We report measurements of re-suspended near-source volcanic dust, which may form a component of the plume downwind. Elevated levels ofSO4
2–, Cl–, F–,H+, Na+, K+ and Mg2+ were observed around the 10 m particle diameter in this dust. The volcanic SO4
2– flux leaving the craterwas 0.07 kg s–1. 相似文献
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Patrick J. Sheridan 《Journal of Atmospheric Chemistry》1989,9(1-3):267-282
Cascade impactor samples were collected over the Alaskan Arctic during the first three research flights of AGASP-II. These samples were analyzed using analytical electron microscopy to determine the morphology, mineralogy and elemental composition of individual particles. For analytical considerations, a typical impactor sample was run for approximately 20 min, thus giving excellent time resolution of discrete events.Samples collected during flights 201 and 202 consisted of stratospheric aerosol and lower-altitude haze samples. Stratospheric samples were characterized by moderate loadings of H2SO4 droplets with relatively few particles of other types. Samples collected in tropospheric haze layers generally exhibited light-to-moderate particle loadings. H2SO4 was again the most prevalent species, with crustal and anthropogenic particles also observed. One sample taken over south-central Alaska near the end of flight 203 showed high concentrations of solid crustal particles, with relatively little associated H2SO4. Giant particles larger than 5 m were occasionally observed in this aerosol. The composition of this material closely matches that of bulk ash from the Mt. Augustine volcano, which erupted 9–13 days before collection of this sample. This brings forth the possibility that pockets of ash-rich aerosol existed over parts of south and central Alska during the AGASP-II field mission. There is no evidence that these volcanic aerosols were present in the AGASP study area north of the Brooks Range. 相似文献
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相山地区如意亭深钻CUSD4孔钻探技术研究 总被引：3，自引：0，他引：3
相山地区如意亭深钻CUSD4孔是中核集团龙灿工程下属子课题《相山基础地质研究》项目的第三个钻孔,设计孔深1600m。该钻孔于2016年8月12日开钻,至2016年12月6日,达到地质目的层位,终孔深度1435. 58m,平均台月效率406. 27m/台月。采用液动冲击器+P口径绳索取心钻具+锯齿型金刚石钻头组合钻进方法,在施工中取得良好使用效果,与同地区普通绳索取心钻进相比,钻进时效提高30%以上,钻头使用寿命提高20%以上。全孔岩心采取率98. 10%,破碎带岩心采取率达到99%。本文主要介绍了如意亭深钻CUSD4孔的施工工艺,可为类似地层钻孔提供借鉴。 相似文献
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The differences of the size distribution of polycyclic aromatic hydrocarbons (PAHs) between urban and rural sites of Guangzhou, China 总被引：11，自引：1，他引：11
Size distribution aerosol samples collected at two urban locations (Liwan and Wushan) and a suburban location (Xinken) in Guangzhou (South China) in autumn using a MOUDI (Micro-orifice Uniform Deposit Impactor) have been analyzed for 13 polycyclic aromatic hydrocarbons (PAHs) by gas chromatography with mass selective detection (GC-MS). Different PAH size distribution models were found for urban locations and a suburban location. The particle size distributions of PAHs tend to shift toward a larger size in a suburban location than in an urban location caused by aerosol aging processes. The ratios of total-PAH/TSP changed greatly during different sampling periods, even though the samplings were conducted consecutively. This can be the result of reactions between PAHs and atmospheric photooxidants, and the formation of SOAs (secondary organic aerosols) during the aging process. Adsorption behavior on available aerosol surface area, absorption behavior in available aerosol organic mass and multilayer adsorptive accumulation in coarse mode aerosols were the three mechanisms which control the size distribution of PAHs. 相似文献