scholarly journals Discovery of Discrete Structured Bubbles within Lunar Regolith Impact Glasses

2012 ◽  
Vol 2012 ◽  
pp. 1-3 ◽  
Author(s):  
Marek S. Zbik ◽  
Yen-Fang Song ◽  
Chun-Chieh Wang ◽  
Ray L. Frost
Keyword(s):  
Fine Particles ◽  
Lunar Regolith ◽  
3D Structure ◽  
Lunar Soil ◽  
The Novel ◽  
3D Tomography ◽  
Lunar Material ◽  
Soil Constituent ◽  
Dust Fraction ◽  
Tomography Reconstruction

The unusual morphology and internal structure of bubbles within lunar regolith impact glasses have been studied using traditional scanning electron microscopy and the novel technique transmission X-ray microscopy (TXM), with 3D tomography reconstruction. Here, we show the previously unknown phenomenon of building a highly porous cellular structure within bubbles in glassy particles of the dust fraction of lunar regolith. Vesicles within studied lunar glasses are filled in with submicron-sized particles as shown in the presented micrograph. These particles consist of glass nano in size elements. What is shown in the TXM tomography reconstruction anaglyph demonstrates cellular-like, 3D structure where oblique probably glassy fine particles down to 100 nm in diameter build chains of sophisticated network. It also may be suggested that submicron and nano-sized grains present in lunar regolith are the result of particle liberation from broken glassy vesicles. This liberation takes place when regolith is exposed to constant impact pulverisation. Liberated particles are permanently enriching lunar soil in the finest soil constituent. This constituent presence in lunar regolith may be responsible for the unusual behaviour of lunar material. This unusual constituent of lunar regolith and its properties have to be better understood before our permanent lunar exploration begins.

Control of Drilling and Coring Device Based on Online Identification

2013 ◽  
Author(s):  
Qiquan Quan ◽  
S. Li ◽  
S. Jiang ◽  
X. Hou ◽  
Z. Deng
Keyword(s):  
Object Recognition ◽  
Lunar Regolith ◽  
Lunar Soil ◽  
Recognition System ◽  
Current Level ◽  
Support Vector ◽  
Drilling Process ◽  
Operating Modes ◽  
Online Identification ◽  
Lunar Environment

This paper presents a drilling and coring device for the lunar exploration, which is possibly utilized to acquire the lunar regolith with a certain depth. The drilling device is composed of three components: rotary unit, percussive unit and penetrating unit. The rotary-percussion drill can work in two different operating modes: rotary mode and rotary-percussive mode, depending on the properties of cut object. In the relatively loose regolith, rotation and penetration can make the drill work in a well state. However, once rock is encountered in the drilling process, besides rotation and penetration, percussion must be launched to reduce the drilling power and the required penetrating force. Due to the indetermination of the lunar environment, it is not easy to control the coring drill to adapt to the encountered conditions. To obtain a high coring ratio with relatively low power, an intelligent drilling strategy is inevitably proposed to accomplish the drilling process control. Considering the lunar soil simulant should cover the possible composition of real lunar soil, simulant are classified into several levels based on the generalized drillability. For each level of drillability of lunar soil simulant, experiments are conducted to get the characteristics in frequency-domain of rotary torque output. The sampled characteristics of rotary torque output are utilized to train the object-recognition system based on Support Vector Machine (SVM). Information in all the levels of drillability of lunar soil simulant is stored in the object-recognition system as an expert system. To understand the properties of the drilling object, rotary torque is selected to identify the level of drillability of simulant in drilling process. Subsequently, once the level is obtained, drilling strategy is adjusted to adapt to the current level correspondingly in real time. Experiments are conducted to verify the intelligent drilling strategy successfully.

scholarly journals Evaluation of Cellular Effects Caused by Lunar Regolith Simulant Including Fine Particles

2015 ◽  
Vol 37 (2) ◽  
pp. 139-148
Author(s):  
Masanori HORIE ◽  
Takeo MIKI ◽  
Yoshiyuki HONMA ◽  
Shigeru AOKI ◽  
Yasuo MORIMOTO
Keyword(s):  
Fine Particles ◽  
Lunar Regolith ◽  
Cellular Effects ◽  
Lunar Regolith Simulant

Research of Formed Lunar Regholit Analog AGK-2010 / Badania wytworzonego analogu gruntu księżycowego AGK-2010

2013 ◽  
Vol 58 (2) ◽  
pp. 551-556
Author(s):  
Stanisław Bednarz ◽  
Mirosław Rzyczniak ◽  
Andrzej Gonet ◽  
Karol Seweryn
Keyword(s):  
Grain Size ◽  
Shear Strength ◽  
Oil And Gas ◽  
Lunar Regolith ◽  
Lunar Soil ◽  
Research Centre ◽  
Mechanical Parameters ◽  
The Moon ◽  
The Cost ◽  
Academy Of Sciences

The results investigations of a soil having similar properties as lunar regolith performed at the Department of Drilling and Geoengineering, Faculty of Drilling, Oil and Gas, AGH University of Science and Technology in Kraków are presented in this paper. The research was carried out jointly with the Space Research Centre, Polish Academy of Sciences in Warsaw. The objective of the cooperation was to minimize the cost of tests of penetrator KRET, which will be used on the surface of the Moon. The American lunar regolith (e.g. CHENOBI) was used as reference soil. The most important properties were presented graphically in the form of figures and tables: grain size distribution, selected physical properties (bulk density, colour), selected mechanical parameters (shear strength, inner friction strength, cohesion). As a result the first Polish lunar soil analog AGK-2010 was produced.

Thermal conduction in a composite circular cylinder: a new technique for thermal conductivity measurements of lunar core samples

1980 ◽  
Vol 293 (1406) ◽  
pp. 571-598 ◽  
Keyword(s):  
Thermal Conductivity ◽  
Thermal Conduction ◽  
Lunar Regolith ◽  
Lunar Soil ◽  
New Technique ◽  
Conductivity Measurements ◽  
Core Samples ◽  
Present Technique ◽  
A New Technique ◽  
Lunar Core

A new technique has been developed for the measurement of the thermal conductivity of lunar core samples. According to this technique, the core sample is heated radiatively from the outside at a known rate, the temperature is measured at the surface of the coretube, and the thermal conductivity of the sample is determined by comparing the measured temperature with the theory. The technique conforms with the aims of lunar sample preservation in that the sample remains intact after the measurements. The solution, as obtained in this paper, of a thermal conduction equation for a composite circular cylinder, with zero initial temperature and a constant heat-flux at its outer boundary, provides a theoretical basis for the present technique. Because of their mathematical similarity, the corresponding problems for a composite slab or sphere were also solved and the solutions are presented for possible future application to the thermal conductivity measurements. Testing demonstrated the feasibility of the new technique. The thermal conductivity of a simulant lunar soil sample, as determined by the present technique under vacuum conditions at about 300 K for sample densities of 1.47-1.67 g cm -3 , is 2.05-2.65 x 10 -3 W m -1 K -1 , which compares favourably with that of the same sample, 1.61-2.89 x 10 -3 W m -1 K -1 at sample densities of 1.50-1.75 g cm -3 , as measured under similar conditions by the standard line heat source technique. We describe in detail the experimental apparatus construction and procedure; in particular, the number of precautions taken to preserve the samples from disturbances and to improve the measurement results. This technique was successfully applied to the thermal conductivity measurement of two Apollo 17 drill-core samples. The results, 1.9-4.9 x 10 -3 W m -1 K -1 , which is intermediate between the values of thermal conductivity of the lunar regolith determined in situ (0.9-1.3 x 10 -2 W m -1 K -1 and those of lunar soil samples measured in the laboratory under simulated lunar surface conditions (0.8-2.5 x 10 -3 W m -1 K -1 ) presents an important clue to the understanding of heat transportation mechanisms in the lunar regolith.

scholarly journals Volcanic history of the Imbrium basin: A close-up view from the lunar rover Yutu

2015 ◽  
Vol 112 (17) ◽  
pp. 5342-5347 ◽  
Author(s):  
Jinhai Zhang ◽  
Wei Yang ◽  
Sen Hu ◽  
Yangting Lin ◽  
Guangyou Fang ◽  
...  
Keyword(s):  
Lunar Regolith ◽  
Landing Site ◽  
Lunar Soil ◽  
Lunar Rover ◽  
Surface Exploration ◽  
Mantle Reservoir ◽  
History Of ◽  
Radar Measurements ◽  
Residual Melt

We report the surface exploration by the lunar rover Yutu that landed on the young lava flow in the northeastern part of the Mare Imbrium, which is the largest basin on the nearside of the Moon and is filled with several basalt units estimated to date from 3.5 to 2.0 Ga. The onboard lunar penetrating radar conducted a 114-m-long profile, which measured a thickness of ∼5 m of the lunar regolith layer and detected three underlying basalt units at depths of 195, 215, and 345 m. The radar measurements suggest underestimation of the global lunar regolith thickness by other methods and reveal a vast volume of the last volcano eruption. The in situ spectral reflectance and elemental analysis of the lunar soil at the landing site suggest that the young basalt could be derived from an ilmenite-rich mantle reservoir and then assimilated by 10–20% of the last residual melt of the lunar magma ocean.

A Novel System for Fine Particle Concentration Measurement

2014 ◽  
Vol 901 ◽  
pp. 29-33
Author(s):  
Ming Ru Guo ◽  
Wen Zhong Lou ◽  
Li Na Ren ◽  
Yu Fei Lu
Keyword(s):  
Fine Particle ◽  
Particle Concentration ◽  
Fine Particles ◽  
Ultrasonic Attenuation ◽  
Ultrasonic Transducer ◽  
Dust Cloud ◽  
Measuring System ◽  
The Novel ◽  
The Public ◽  
Measuring Devices

It is important to monitoring the fine particles (PM2.5) in atmosphere as it threatens the public health all over the world. But the existing concentration measuring devices have shortcomings in speed and range. A novel fine particle concentration measuring system based on the ultrasonic attenuation was designed in this paper, which could help to solve the problem. Firstly the mechanism of ultrasonic attenuation in dust cloud was studied to verify the relationship between the concentration and the ultrasonic attenuation. Then the novel concentration measuring system was designed. The micro ultrasonic transducer array was introduced into the system, so the system can be sensitive as well as small. Finally, experiment was conducted to check the performance of this measuring system, and the results show that it could realize measurement quickly.

scholarly journals 3D tomography reconstruction improved by integrating view registration

2019 ◽  
Vol 58 (10) ◽  
pp. 2596 ◽  
Author(s):  
Ning Liu ◽  
Qingchun Lei ◽  
Yue Wu ◽  
Lin Ma
Keyword(s):  
3D Tomography ◽  
Tomography Reconstruction

scholarly journals In silico characterization of the NiRAN domain of RNA-dependent RNA polymerase provides insights into a potential therapeutic target against SARS-CoV2

2020 ◽  
Author(s):  
Abhisek Dwivedy ◽  
Richard Mariadasse ◽  
Mohammed Ahmed ◽  
Deepsikha Kar ◽  
Jeyaraman Jeyakanthan ◽  
...  
Keyword(s):  
Active Site ◽  
In Silico ◽  
3D Structure ◽  
Drug Repurposing ◽  
The Novel ◽  
Lead Compounds ◽  
Nucleotidyl Transferase ◽  
Domain Organisation ◽  
Novel Coronavirus ◽  
In Silico Characterization

Apart from the canonical fingers, palm and thumb domains, the RNA dependent RNA polymerases (RdRp) from the viral order Nidovirales possess two additional domains. Of these, the function of the Nidovirus RdRp associated nucleotidyl transferase domain (NiRAN) remains unanswered. The elucidation of the 3D structure of the RdRp from the novel coronavirus – SARS-CoV2, provided the first ever insights into the domain organisation and possible functional characteristics of the NiRAN domain. Using in silico tools, this study predicts that the NiRAN domain assumes a kinase or phosphotransferase like fold and binds GTP and UTP at its proposed active site. Additionally, using molecular docking this study predicts the binding of five well characterized anti-microbial compounds at the NiRAN domain active site and their drug-likeliness and DFT properties. In line with the current global COVID-19 pandemic urgency, this study provides a new target and potential lead compounds for drug repurposing against SARS-CoV2.

scholarly journals NEW INSIGHTS INTO SOLAR WIND IMPLANTED VOLATILES FOR LUNAR REGOLITH CHARACTERIZATION: A SIMULATION BASED APPROACH

2018 ◽  
Vol IV-4 ◽  
pp. 199-206
Author(s):  
S. Shukla ◽  
S. Majumdar ◽  
A. Maiti ◽  
S. Kumar
Keyword(s):  
Activation Energy ◽  
Solar Wind ◽  
Frequency Domain ◽  
Particle Density ◽  
Lunar Regolith ◽  
Lunar Soil ◽  
Crystal Defects ◽  
Mining Sites ◽  
Interplanetary Coronal Mass Ejection ◽  
Mass Ejection

<p><strong>Abstract.</strong> The effect of solar wind implanted volatiles into the top 100 nm of the lunar regolith plays a significant role in quantitatively assessing the lunar surface isotopic composition. In essence, these volatiles can either quickly sputter out of the surface or be retained. The implantation processes exhibit a functional dependency on the surface temperature, ilmenite abundance and the activation energy associated with the optical maturity of the lunar soil. The prime focus of this study is to simulate the implication of these incident volatiles in characterizing the regolith for a better insight into the modeling of lunar exosphere during both Interplanetary Coronal Mass Ejection (ICME) and usual cases. Additionally, the proposed model quantifies the total lunar oxygen repository along with determining the associated textural and frequency domain measures for probable future lunar <sup>3</sup>He mining sites. In this 30-day simulation, the particles bombard the reconstructed lunar grid wherein each cell displays varying particle density at a given local time. Moreover, both the activation energy and TiO<sub>2</sub> content are assumed to be in a Gaussian distribution having (&amp;mu;, &amp;sigma;) of (0.96, 0.025) and (12.52, 3.44) respectively. It has been found that the surfaces characterized by high activation energy tend to retain solar wind implants due to the large numbers of crystal defects. However, for H and heavy trace ions, intermediate activation energy range demonstrates diurnal behavior with the diffusive loss at local noon time. The study also finds an intriguing relationship between the lunar O<sub>2</sub> and retained H sites (frequency domain). Furthermore, this could be utilized as a generic exospheric modeling paradigm for airless bodies and contribute to the understanding of the physical processes associated with solar astronomy.</p>

scholarly journals Topology-based classification of tetrads and quadruplex structures

2019 ◽  
Vol 36 (4) ◽  
pp. 1129-1134 ◽  
Author(s):  
Mariusz Popenda ◽  
Joanna Miskiewicz ◽  
Joanna Sarzynska ◽  
Tomasz Zok ◽  
Marta Szachniuk
Keyword(s):  
Nucleic Acid ◽  
3D Structure ◽  
Data Bank ◽  
Supplementary Information ◽  
The Novel ◽  
Disease Treatment ◽  
Structure Topology ◽  
Secondary Structure Topology ◽  
Nucleic Acid Structures

Abstract Motivation Quadruplexes attract the attention of researchers from many fields of bio-science. Due to a specific structure, these tertiary motifs are involved in various biological processes. They are also promising therapeutic targets in many strategies of drug development, including anticancer and neurological disease treatment. The uniqueness and diversity of their forms cause that quadruplexes show great potential in novel biological applications. The existing approaches for quadruplex analysis are based on sequence or 3D structure features and address canonical motifs only. Results In our study, we analyzed tetrads and quadruplexes contained in nucleic acid molecules deposited in Protein Data Bank. Focusing on their secondary structure topology, we adjusted its graphical diagram and proposed new dot-bracket and arc representations. We defined the novel classification of these motifs. It can handle both canonical and non-canonical cases. Based on this new taxonomy, we implemented a method that automatically recognizes the types of tetrads and quadruplexes occurring as unimolecular structures. Finally, we conducted a statistical analysis of these motifs found in experimentally determined nucleic acid structures in relation to the new classification. Availability and implementation https://github.com/tzok/eltetrado/ Supplementary information Supplementary data are available at Bioinformatics online.

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