Streams of the particle ejected from the Sun and the extreme space weather conditions like storms, high-speed streamers (HSSs), interplanetary coronal mass ejections (ICMEs), corotating interaction regions (CIRs), and interplanetary shocks (IS) termed as geomagnetic storms have massive influence in the climate and components of the Earth's upper atmosphere such as total electron content (TEC). The study of TEC helps to understand variations in ionospheric electron density during geomagnetic storms. Global ionospheric maps of TEC are a real-time mapping of GPS observations produced by ground-based stations. In this paper, we have analyzed three intense geomagnetic storms of the year 2015:

We present an extensive catalog of 5405 early-type dwarf (dE) galaxies located in the various environments, i.e., clusters, groups, and fields, of the local universe (z < 0.01). The dEs are selected through visual inspection of the Legacy survey’s g–r–z combined tricolor images. The inspected area, covering a total sky area of 7643 deg2, encompasses two local clusters (Virgo and Fornax), 265 groups, and the regions around 586 field galaxies of M K < −21 mag. The catalog aims to be one of the most extensive and publicly accessible collections of data on dEs, despite its complex completeness limits, which may not accurately represent its statistical completeness. The strength of the catalog lies in the morphological characteristics, including nucleated, tidal, and ultradiffuse dEs. The two clusters contribute nearly half (2437 out of 5405) of the dEs, and the 265 groups contribute 2103 dEs. There are 864 dEs in 586 fields, i.e., ∼1.47 dEs per field. Using a standard definition commonly used in literature, we identify 100 ultradiffuse galaxies (UDGs), which compose ∼2% of the dE population. We find that 40% of our sample dEs harbor a central nucleus, and among the UDG population, a majority (79%) are nonnucleated. About 1.3% of dEs suffer from ongoing tidal disturbance by nearby massive galaxies, and only 0.03% show a sign of recent dwarf–dwarf mergers. The association between dEs and their nearest bright neighbor galaxies suggests that dEs are more likely created where their neighbors are non-star-forming ones.

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In this experiment, an atmospheric pressure dielectric barrier discharge (DBD) generated with a water electrode is investigated by means of optical measurements and imaging. The discharge was generated using a high voltage (0-20kV) power supply operating at 10-30 kHz with water as one of the electrode and borosilicate glass as a dielectric barrier of 2.5mm thickness. This paper reports the generation and characterization of atmospheric pressure plasma in nitrogen environment and its application in the surface modification of polyethylene terephthalate (PET). The generated plasma has been characterized by image analysis and optical emission spectroscopy. Our results showed that the distribution of micro-discharges depends significantly on the inter electrode gap and applied voltage. In order to characterize the discharge, electron temperature has been determined by using line intensity ratio method. The results showed that Te depends on applied voltage and pressure inside the chamber. The values of Te were found to be 1.40 eV and 0.95 eV applied at 1kV and 10kV voltage using 1% concentration. The discharge was produced at various conditions for the study of effectiveness of treatment on the surface property of Polyethylene terephthalate (PET). After the treatment of the sample in different treatment time: 10s, 20s, 40s, and 60s, the hydrophobic properties of sample changed to the hydrophilic. To investigate the effect of plasma treatment on Polyethylene terephthalate (PET) polymer contact angle was measured by using goniometer with water as a testing liquid. The surface properties of the untreated and plasma treated PET samples were characterized by contact angle measurement, and surface energy analysis. Before treatment the contact angle for untreated sample was 77.1° and after treatment its contact angle becomes 38.7° , 35.04° , 33.6° and 31.6° respectively.