Spatial and Temporal Properties of the Solar Cycle from RATAN-600 Microwave Observations

Geomagnetism and Aeronomy - The study involves the obtainment of regular tracers of the solar cycle in the radio range by activity manifestations in the chromosphere and corona. Our research method...     

圣彼得堡土地利用格局现状特征及形成机制

以圣彼得堡市为例,依据1948、1987和2016年土地利用数据计算居住、工业和商业用地的区位熵值并分析其变化,基于统计小区、圈层式及扇形分布3个视角,运用GIS分析计划与市场经济影响下的城市用地空间分布特征。研究结果表明,居住、工业和商业用地的空间分布规律不同：① 3类用地在城市整体空间分布中均表现出一定的分散特征,其中,居住用地空间分布表现最为分散,工业用地呈现出分区域性布局特征,相比而言商业用地空间聚集程度最高;② 商业用地在核心圈层处于主导地位,工业用地在老城区圈层为主导地位,居住用地在近郊区圈层为主导地位,远郊区圈层仍处于初步发展阶段,城市景观发展尚未成熟;③ 对比圈层式和象限式结构各类用地区位熵值分布结果,提出圣彼得堡市3类用地空间分布扇形结构特征明显,说明沿主要交通线路是现代城市用地空间扩展主要方式,其中工业用地在城市空间分布中占据更为有利的交通区位优势,居住用地次之,商业用地在城市中心区域中分布不足。圣彼得堡城市用地空间分布形成主要机制总结为以下5个方面：前苏联时期城市用地空间结构主要框架的保持;行政区划调整为城市用地结构改善提供了路径;市场经济下住房体制改革推进了城市居住郊区化;土地市场对土地功能置换进程作用较弱;产业转型缓慢导致老城区仍主要为生产中心。     

Computation of the horizontal size of the RATAN-600 beam pattern for the “Southern Sector with a Flat Reflector” mode with allowance for the parameters of primary feeds

We report the spectra of the horizontal size of the beam pattern of the RATAN-600 radio telescope operating in the “Southern Sector with a Flat Reflector” observing mode computed in the geometrical optics approximation with allowance for the beam patterns of various primary feeds used in observations with the solar receiver facility in the 3–18 GHz frequency interval. In particular, we show that in the case broadband, spiral, or sinuous feeds are used, the width of the horizontal beam pattern of the antenna decreases with wavelength in the low-frequency part of the spectrum.We compute the spectra of the sizes of two compact local sources on the Sun, which show that the results obtained have to be taken into account when determining the parameters of local sources.     

Lazurite: Validation as a Mineral Species with the Formula Na7Ca(Al6Si6O24)(SO4) $${\text{S}}_{3}^{{\bullet - }}$$ ⋅H2O and New Data

Geology of Ore Deposits - The status of lazurite as a valid mineral species has been confirmed. The neotype specimen from the Malaya Bystraya gem lazurite deposit, Baikal Lake area has been studied...     

A Method of Forecasting Solar Activity Based on Radio Astronomical Observations

We present the results of forecasting flare activity based on the data from microwave spectropolarimetric observations of active regions (ARs) obtained with the RATAN-600 radio telescope and the X-ray data from the GOES satellite as well as monitoring data. The method is designed for short-term (1–3-days) flare forecasts. Proton events are considered as part of the general flare problem. Obtaining a reliable forecast is a difficult process in view of the multi-parameter and multi-dimensional system of plasma parameter variations and multiple non-linear interconnections.We used a modified Tanaka–Enome criterion, as well a database of observational material collected over many years. The forecasting efficiency was analyzed depending on the threshold values of the criterion. We show that the quality of the radio astronomical forecast is determined by the level of sensitivity of the detector at short centimeterwavelengths and by the solar activity level.     

Sulfur-Bearing Sodalite,Hackmanite, in Alkaline Pegmatites of the Inagli Massif (Aldan Shield): Crystal Chemistry,Photochromism, and Luminescence

Geology of Ore Deposits - Abstract—Sulfur-containing sodalite, hackmanite, has been found for the first time in alkaline pegmatites of the Inagli alkaline–ultramafic massif, South...