An improved method of measuring tropospheric NO2 and RO2 by matrix isolation and electron spin resonance

A cryogenic system for the airborne and ground based sampling of ambient radicals by matrix isolation is described. The trapped radicals, e.g., NO₂ and RO₂, are analyzed by ESR. The technique has been improved, mainly by addition of water vapor to the sampled air, to yield a collection efficiency of (90±10)% and a lower detection limit of about 20 ppt, but it still does not distinguish between the different RO₂. Careful calibration reduced the measurement error (1 ) to ±10% for NO₂ and ±15% for HO₂. Two diurnal variations of RO₂ and NO₂ at ground level and vertical profiles in the lower troposphere are presented.     

Electron paramagnetic resonance characteristics of the humic acids from a podzol

A study has been made of solid and solution electron paramagnetic resonance (EPR) spectra of humic acids from different horizons in a podzolic soil. Hyperfine splitting was observed in the solution spectra of humic acids from all horizons and depended on the strength of alkali and the period of dissolution. The upper organic horizons L, F and O₁ contained humic acids with some spectral characteristics in common with lignin. Humic acid from the lower horizons showed different spectra. At least 5 different radical signals were present.     

高频多普勒台阵中的若干技术问题

为了研究电离层动力学特性,1985年9月在武汉建成了一个由三个台站组成的高频多普勒台阵和卫星信标法拉第台阵。文中介绍了这个台阵的布局和多普勒接收系统中的一些技术细节。这些技术措施保证了在多普勒图中清晰地显示多径现象和有效地消除小不均匀体的影响。最后还简单地介绍了这个台阵一年来的实测情况。     

Further studies on torbanites and coorongite using transmission electron microscopy and C-isotope analysis

Transmission electron microscopy of torbanites from various localities in eastern Australia has revealed micro-organisms of possible methanogenic affinity. Botryococcus remains in the torbanites displayed close resemblance to the rubbery B. braunii accumulations deposited in recent bodies of freshwater origin. Compaction and collapse of structure seem to be the major visible alteration to the algal colonies. C-isotope compositions of the torbanites favour methanogenic activity. Comparison with recent botroyococcal accumulations support diagenetic alteration at a very early stage of deposition.     

Simultaneous measurements of peroxy and nitrate radicals at Schauinsland

We present simultaneous field measurements of NO₃ and peroxy radicals made at night in a forested area (Schauinsland, Black Forest, 48° N, 8° N, 1150 ASL), together with measurements of CO, O₃, NO _x , NO _y , and hydrocarbons, as well as meteorological parameters. NO₂, NO₃, HO₂, and (RO₂) radicals are detected with matrix isolation/electron spin resonance (MIESR). NO₃ and HO₂ were found to be present in the range of 0–10 ppt, whilst organic peroxy radicals reached concentrations of 40 ppt. NO₃, RO₂, and HO₂ exhibited strong variations, in contrast to the almost constant values of the longer lived trace gases. The data suggest anticorrelation between NO₃ and RO₂ radical concentrations at night.The measured trace gas set allows the calculation of NO₃ and peroxy radical concentrations, using a chemical box model. From these simulations, it is concluded that the observed anthropogenic hydrocarbons are not sufficient to explain the observed RO₂ concentrations. The chemical budget of both NO₃ and RO₂ radicals can be understood if emissions of monoterpenes are included. The measured HO₂ can only be explained by the model, when NO concentrations at night of around 5 ppt are assumed to be present. The presence of HO₂ radicals implies the presence of hydroxyl radicals at night in concentrations of up to 10⁵ cm^–3.     

A simple accelerated rock weathering method to predict acid generation kinetics

The development of effective, and economical pre-development waste rock management plans requires an accurate estimate of the quality of drainage generated during mining. This study was conducted to determine if a simple accelerated rock weathering method with lower capital and personnel costs can be used in lieu of the elaborate and costly ASTM method to predict the quality of drainage generated. It involves subjecting rock samples to a constant relative humidity and temperature for 7 days and leach flooding the weathered samples on the 7th day. The acid production rate from the new weathering method correlates quite well with the net neutralization potential generated from the standard acid-base accounting procedure (R²=0.940) which has been demonstrated to be correct 90% of the time in assessing overburden quality, and a mineralogical method (R²=0.924). For investigators interested in generating weathering kinetic parameters, the simple and less costly accelerated weathering method is proposed.     

Effect of depositional method on the undrained behavior and microstructure of sand with silt

It has been known for many years that depositional method plays an important part in the results of laboratory testing of clean sands. In this paper, undrained triaxial compression tests were performed on specimens composed of Nevada sand with 20% non-plastic silt content using a variety of depositional methods that include slurry deposition, water sedimentation, air pluviation, mixed dry deposition, and dry funnel deposition. It was found that there was a marked difference in the undrained behavior even though the density and stress conditions were identical. The conclusion was that the soil fabric was responsible for this result. Using the scanning electron microscope, a method was developed to examine and quantify the microstructure of silty sand. These results appear to indicate that there are internal particle structures in sand with silt and their relative quantities correlate with the observed macroscopic undrained behavior.     

全球定位系统(GPS)技术的最新进展第五讲利用双频GPS观测值建立电离层延迟模型

介绍了电离层的概况，GPS信号在电离层中的传播，电离层改正模型以及利用GPS双频观测值来建立电离层延迟或VTEC模型的原理、方法和结果。     

GPS在港口引航中的应用

分析了利用差分GPS技术为港口船舶进出港进行精确导航的引航系统的关键技术，介绍了新近开发的一套港口船舶领航软件“安全领航员SafeGuide1．0”的有关功能，利用该软件在秦皇岛港成功进行了试验。     

Genetic Mechanism of Mineral Inclusions in Zircons from the Khondalite Series, Southeastern Inner Mongolia

The early Precambrian khondalite series is widely distributed in the Jining-Zhuozi-Fengzhen-Liangcheng area, southeastern Inner Mongolia. The khondalite series mainly consists of sillimanite garnet potash feldspar (or two-feldspar) gneiss and garnet biotite plagioclase gneiss. These gneissic rocks have commonly experienced granulite-facies metamorphism. In zircons separated from sillimanite garnet potash feldspar gneisses, many mineral inclusions, including Sil, Grt, Ky, Kfs, Qtz and Ap, have been identified by the Laser Raman spectroscopy. Generally, prograde metamorphic mineral inclusion assemblages such as Ky + Kfs + Qtz + Ap and Ky + Grt + Kfs + Qtz are preserved in the core of zircon, while peak granulite-facies metamorphic minerals including Sil + Grt + Kfs + Qtz and Sil + Grt + Kfs + Qtz + Ap are identified in the mantle and rim of the same zircon. However, in some zircons are only preserved the peak metamorphic minerals such as Sil + Grt + Kfs + Qtz and Sil + Grt + Kfs + Qtz + Ap from core to ri