scholarly journals Geophysical search for fragments of the Sterlitamak meteorite

Author(s):  
OVCHARENKO Arkadiy Vasil’evich ◽  

Relevance is determined by the fact that meteorites are of great importance for the direct study of the substance of the Universe, therefore, when new meteorites fall, maximum efforts are made to detect them and study the conditions of the fall. The purpose of the work is to further study the meteorite crater and search for large fragments of the Sterlitamak meteorite not found at the first stage of study using geophysical methods. The story of the fall and searches for the main fragment of the Sterlitamak meteorite, which fell on August 17, 1990 at 23 h 25 min, on the field of the Sterlitamak state farm is described. When it fell, a crater with a diameter of 10 m and a depth of 4 m was formed. The fall was accompanied by a bright glow and thunderous rumbles. A glow was observed over the crater in the dark. A high-speed searching for the meteorite was organized by collecting meteorite debris around the crater. At the same time, a mine detector was used. The crater was excavated with an excavator to a depth of 18–20 m. Fragments weighing 6.6; 3.06; 0.875; 0.363 kg were found. A year later, the main body weighing 315 kg was accidentally found in the dumps. Chemical analysis of the substance showed that it is an iron-nickel meteorite, 98% of the thickness are the minerals kamacite, tenite and schreibersite. Results. In 2014–2015, the authors carried out magnetic surveying around the crater and on the ice of the lake, which was formed at the excavation site, in order to search for fragments of the meteorite, which were probably missed at the initial stage. Maps of the magnetic field and terrain of the crater are given. Magnetic anomalies are identified, which are presumably associated with new fragments of the meteorite. The probable depths of the meteorite fragments are 2–4 m. In-depth sections of the magnetization for these anomalies obtained by the method of magnetic tomography, are given, as well as the results of a surface survey of the dump area using a metal detector. Weakly magnetic samples were found containing sprayed metal and metal balls with a diameter of 0.5–1.0 mm. These samples originally formed a zone of impact metamorphism, which was destroyed by excavation operations. It is shown that the territory is promising for searching for new large fragments of the meteorite and studying the processes of impact metamorphism. It is planned to further study the crater by means of electrical exploration and GPR sounding.

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Jayanti Mishra ◽  
Bhumika Kumar ◽  
Monika Targhotra ◽  
P. K. Sahoo

Abstract Background Breast cancer is the most frequent cancer and one of the most common causes of death in women, impacting almost 2 million women each year. Tenacity or perseverance of breast cancer in women is very high these days with an extensive increasing rate of 3 to 5% every year. Along with hurdles faced during treatment of breast tumor, one of the crucial causes of delay in treatment is invasive and poor diagnostic techniques for breast cancer hence the early diagnosis of breast tumors will help us to improve its management and treatment in the initial stage. Main body Present review aims to explore diagnostic techniques for breast cancer that are currently being used, recent advancements that aids in prior detection and evaluation and are extensively focused on techniques that are going to be future of breast cancer detection with better efficiency and lesser pain to patients so that it helps to a physician to prevent delay in treatment of cancer. Here, we have discussed mammography and its advanced forms that are the need of current era, techniques involving radiation such as radionuclide methods, the potential of nanotechnology by using nanoparticle in breast cancer, and how the new inventions such as breath biopsy, and X-ray diffraction of hair can simply use as a prominent method in breast cancer early and easy detection tool. Conclusion It is observed significantly that advancement in detection techniques is helping in early diagnosis of breast cancer; however, we have to also focus on techniques that will improve the future of cancer diagnosis in like optical imaging and HER2 testing.


Materials ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 3497 ◽  
Author(s):  
Daiki Nakajima ◽  
Tatsuya Kikuchi ◽  
Taiki Yoshioka ◽  
Hisayoshi Matsushima ◽  
Mikito Ueda ◽  
...  

A superhydrophilic aluminum surface with fast water evaporation based on nanostructured aluminum oxide was fabricated via anodizing in pyrophosphoric acid. Anodizing aluminum in pyrophosphoric acid caused the successive formation of a barrier oxide film, a porous oxide film, pyramidal bundle structures with alumina nanofibers, and completely bent nanofibers. During the water contact angle measurements at 1 s after the water droplet was placed on the anodized surface, the contact angle rapidly decreased to less than 10°, and superhydrophilic behavior with the lowest contact angle measuring 2.0° was exhibited on the surface covered with the pyramidal bundle structures. As the measurement time of the contact angle decreased to 200–33 ms after the water placement, although the contact angle slightly increased in the initial stage due to the formation of porous alumina, at 33 ms after the water placement, the contact angle was 9.8°, indicating that superhydrophilicity with fast water evaporation was successfully obtained on the surface covered with the pyramidal bundle structures. We found that the shape of the pyramidal bundle structures was maintained in water without separation by in situ high-speed atomic force microscopy measurements.


Lubricants ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 75
Author(s):  
Takefumi Otsu ◽  
Romeo Glovnea ◽  
Joichi Sugimura

This article describes experimental and theoretical studies on the cavitation phenomena in the grease lubrication film under pure sliding elastohydrodynamic contact. In situ observation tests using the optical interferometry technique were conducted, and the growth of cavitation was captured using a high-speed camera. The results showed that the cavity grew in two stages, which was similar to the behavior in the base oil, and that the cavity growth rate in the initial stage was higher than that in the second stage. In the initial stage, the cavity growth time in the grease was longer than that in the base oil, and the cavity length after the growth depended on the base oil viscosity. It was also found in the test using diurea grease that small cavities were formed by the lumps of thickener. The cavity growth in the initial stage was discussed by numerical simulation of pressure distribution based on a simple rheological model.


2008 ◽  
Vol 22 (31n32) ◽  
pp. 5603-5608 ◽  
Author(s):  
JIN SUNG KIM ◽  
HOON HUH ◽  
TAE SOO KWON

This paper introduces the jig set for the crash test and the crash test results of shear bolts which are designed to fail at train crash conditions. The tension and shear bolts are attached to Light Collision Safety Devices(LCSD) as a mechanical fuse when tension and shear bolts reach their failure load designed. The kinetic energy due to the crash is absorbed by the secondary energy absorbing device after LCSD are detached from the main body by the fracture of shear bolts. A single shear bolt was designed to fail at the load of 250 kN. The jig set designed to convert a compressive loading to a shear loading was installed to the high speed crash tester for dynamic shear tests. Two strain gauges were attached at the parallel section of the jig set to measure the load responses acting on the shear bolts. Crash tests were performed with a carrier whose mass was 250 kg and the initial speed of the carrier was 9 m/sec. From the quasi-static and dynamic experiments as well as the numerical analysis, the capacity of the shear bolts were accurately predicted for the crashworthiness design.


2014 ◽  
Vol 17 (3) ◽  
pp. 27-33
Author(s):  
Bac Hoang Bui ◽  
Hung The Khuong ◽  
Thanh Xuan Ngo ◽  
Dung Tien Nguyen

Earthquake is currently one of the biggest concerns in Vietnam, especially, when a number of earthquakes recorded by seismometers in recent years imply the danger of earthquake in the country. In Vietnam, the recorded earthquakes were pinpointed as the consequence of stratigraphic movements along active fault zones. Identifying of the activities of fault is mainly based on tectonics, geomorphology and observation techniques utilizing geophysical methods with data on seismic waves of earthquakes. However, determining the active fault intervals is generally a difficult task which is of the interest of many domestic and worldwide scientists. One of the methods of identifying the active intervals of faults that has been applied in many countries is studying authigenetic clay mineral forming in fault planes and cataclasites due to fault activities. The movement of fault surface will create fault gouges formed at low temperature, the typical of which is illite mineral. In order to date active phases of faults, K-Ar dating of illite mineral is now proved to be an effective method. Based on the successful studies on modern fault activities using the method of K-Ar dating of authigeneticillite, and with the goal of having a general view on the activities of Red Rive Fault, Vietnam and more information on earthquakes caused by this fault, the authors have conducted a study on characteristics of the authigenetic clay minerals formed by fault activities, accordingly identifying their formation periods using K-Ar dating method. Based on the recorded ages, we hope to be able to explain the active fault intervals and its relationship with earthquake activity in the surround areas. In this paper, we are presenting the initial results about characteristics of clay minerals in gouges of the Red River fault zone, Vietnam. Several gouges amples were collected from the Red River fault zone. Then, they were separated into four grain-size fractions (<0.1, 0.1 - 0.4, 0.4 - 1.0, and 1-2µm) using standard gravitational settling and high-speed centrifuging techniques based on a preliminary analysis. The samples after separating were characterized by using FTIR spectroscopy, X-ray diffraction (XRD), Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). The results indicated that authigenetic clay minerals forming in fault planes due to fault activities such as illite, illite/smectite is in samples with significant amounts. These are important results in defining modern active time of Red River fault zone using method of K-Ar dating for authigenetic clay minerals.


Author(s):  
Jian Ding

The experiments of Project 8 have been excellent, but the expected goals still difficult to achieve. So much so that some of the results at your fingertips were also missing. In view of this, the focus of this article is to clarify several easy confused concepts. Only in this way, we can reasonably explain the experimental data. The main points are as follows: 1. The value c of the light speed in vacuum and a particle with zero static mass, both of which do not exist in the reality. That is to say, the so-called a photon's static mass is equal to zero but has energy, which is a paradox that confuses two different definitional domains. 2. In the reality, photons are high-speed particles generated by electromagnetic radiation. They must have the characteristics of (static) mass, energy and wave, in order to describe the main body to aim at photons from different angles. 3. After any main body comes into being electromagnetic radiation, its static mass will inevitably decrease accordingly. 4. The charge-mass ratio of an electron is a physical constant, which is the ratio of its charge to the amount of matter, and is not affected by relativistic effects and electromagnetic radiation. 5. The uncertainty of moving electrons is caused by random electromagnetic radiations. Finally, it is pointed out that if the cyclotron frequency of a single electron is measured, and at the same time, its de Broglie wavelength or frequency can also be measured, then its static mass can be obtained. Even so, the expected goals are still difficult to achieve, because random electromagnetic radiations are always taking away continually the matter composition of the single electron being measured. However, this was precisely a result of the research obtained by Project 8, and had universality, which should be reflect on.


Naše more ◽  
2021 ◽  
Vol 68 (3) ◽  
pp. 175-188
Author(s):  
Ahmad Fauzan Zakki ◽  
◽  
Deddy Chrismianto ◽  
Aulia Windyandari ◽  
Rizaldy Ilham

Several advantages of multihull, such as catamaran, have been extensively discussed in the previous research. Therefore, this research focuses on developing a catamaran hull form for the fish processing vessel hull. The initial stage is determining the principal dimension and exploring the configurations of catamaran hull forms. The existing high-speed craft catamarans have been adopted to determine the parent model main dimensions using a linear regression equation model. Otherwise, the catamarans single demi-hull geometry was developed by converting and modifying the parent model hull form with enlarging the hull displacement to achieve the deadweight capacity and service speed requirements. The demi-hull spacing configuration with s/L 0.17, s/L 0.20, s/L 0.30, and s/L 0.40 on the resistance characteristics, intact stability, and sea-keeping behaviour were also explored. Furthermore, the comparisons with the previously proposed monohull were presented. Regarding the hull resistance performance, the analysis indicated that the catamaran hull form had better total resistance characteristics than the monohull on the service speed over 23 knots. In the case of intact stability, the analysis results presented that the catamaran hull form has better intact stability characteristics than the monohull. The dynamic stability of the catamarans also gave better dynamic stability at the heeling angle below 41.57°. Otherwise, the catamarans with s/L 0.17 and s/L 0.20 have lower dynamic stability than the monohull at the heeling angle larger than 41.57° and 58.03°, respectively. In the sea-keeping performance, the catamaran hull has shown an excellent rolling motion required for the offshore environment loading/unloading process. The large demi hull spacing of the catamarans hull can reduce the effect of the wave creating load on the roll motion response at the Beam Sea.


Author(s):  
A.S. Nikiforov ◽  
◽  
A.E. Karmanov ◽  
E.V. Prikhod’ko ◽  
A.K. Kinzhibekova ◽  
...  

The article contains an analysis of the initial stage of the heating process of high-temperature units. The heating modes used at the enterprises lead to various difficulties: a delay in the heating process or heating at a high speed at which mechanical stresses arise and exceed the permissible values. The proposed graphical dependencies for heating allow us to heat up at the highest possible speeds, taking into account the time spent on drying. In this case, the ultimate strength of refractory materials is not exceeded, which leads to a significant reduction in the time for the heating process.


1998 ◽  
Vol 64 (10) ◽  
pp. 4015-4020 ◽  
Author(s):  
Kiyohiko Nakasaki ◽  
Sachiko Hiraoka ◽  
Hiroyuki Nagata

ABSTRACT This study evaluated the use of grass clippings discharged from golf courses as the raw material for production of a suppressive compost to control Rhizoctonia large-patch disease in mascarene grass. Bacillus subtilis N4, a mesophilic bacterium with suppressive effects on the pathogenic fungusRhizoctonia solani AG2-2, was used as an inoculum in a procedure developed with the aim of controlling composting temperatures and inoculation timing. The population density of mesophilic bacteria in the raw material was reduced to around 5 log10 CFU/g (dry weight) of composting material in the self-heating reaction at the initial stage of composting by maintaining a temperature of 80°C for 1 day. The inoculum was applied immediately, and the composting material was maintained at 40°C for 3 days. This served both to highly concentrate the suppressive bacterium and to achieve sporulation. The temperature was then raised to 60°C and maintained, enabling hygienic, high-speed composting while maintaining the population density of the suppressive bacterium as high as 8 log10 CFU/g (dry weight) in the compost. The suppressiveness of compost made in this way was confirmed in a turf grass disease prevention assay.


2019 ◽  
Vol 24 (1) ◽  
pp. 87-110 ◽  
Author(s):  
David Huntley ◽  
Peter Bobrowsky ◽  
Michael Hendry ◽  
Renato Macciotta ◽  
Melvyn Best

Landslides in the Thompson River valley, British Columbia have the potential to adversely impact vital national railway infrastructure and operations, the natural environment, cultural heritage features, communities, public safety and the economy. To better manage geohazard risks in the primary national transportation corridor, government agencies, universities and railway industry partners are focusing research efforts on the Ripley Landslide, 7 km south of Ashcroft. The internal composition and structure of this very slow-moving landslide as revealed by geophysical surveys and terrain mapping provides contextual baseline data for interpreting slope stability monitoring results and guiding geohazard mitigation efforts. Terrestrial and waterborne geophysical surveys were undertaken using subsets of the following methods: electrical resistivity tomography, frequency electromagnetic conductivity, ground penetrating radar, primary-wave refraction and multispectral analysis of shear-waves, natural gamma radiation, induction conductivity and magnetic susceptibility. Small and irregular anomalies, areas of complex subsurface geometry and groundwater-rich zones are resolved along all terrestrial geophysical survey lines. Terrain mapping and geophysical surveys indicate a high relief bedrock sub-surface overlain by a 10 m to >30 m thick package of complex fine-grained sediments containing groundwater. Planar sub-surface features revealed in surface exposures, borehole logs and geophysical profiles include tabular bedding and terrain unit contacts. Profiles also show discrete curvilinear features interpreted as rotational-translational failure planes in clay-rich beds in the main body of the slide beneath the rail ballast and retaining wall. Integrating data from surficial geology mapping and an array of geophysical methods provided significantly more information than any one technique on its own.


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