scholarly journals Comparison of Shaped Charge Jet Performance Generated by Machined and Additively Manufactured CuSn10 Liners

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7149
Author(s):  
Shengjie Sun ◽  
Jianwei Jiang ◽  
Shuyou Wang ◽  
Jianbing Men ◽  
Mei Li ◽  
...  
Keyword(s):  
High Efficiency ◽  
Rapid Heating ◽  
Research Work ◽  
Side Wall ◽  
Shaped Charge ◽  
Lateral Interaction ◽  
Research Areas ◽  
Heating And Cooling ◽  
Wide Range ◽  
Shaped Charge Jet

The Selective Laser Melting (SLM) technique has attracted attention in a wide range of manufacturing research areas, including the defense industry because of its high efficiency and good consistency of manufactured material properties. Shaped charge liner is the crucial unit in the shaped charge warhead. However, jet performance formed by SLM-produced liner remains to be studied systematically. In the present research work, the SLM technique was applied to manufacture CuSn10 shaped charge liners. Casted CuSn10 liners were also fabricated using the classical turning method for comparison. The grain size of the SLM-produced liner was found to be much smaller than the machined liner due to the rapid heating and cooling rate during the SLM manufacturing process. This contributed to improved jet performance. A flash X-ray photography system was applied to capture jet stretching appearances. Necking appears at the jet tip formed by the machined liner, while the jet formed by the SLM-produced liner remains continuous. Penetration test results show that the penetration depth of the jet formed by the SLM-produced liner is around 27% larger than that formed by the machined liner. Segments along the sidewall of the penetration tunnels were selected for in-depth micro analysis. Energy dispersed spectrum (EDS) surface scanning results indicate the composition at the side wall of the penetrated tunnel. Metallurgical microscope was applied to distinguish four different phase zones of the target. The width of these different zones indicates the severity of the lateral interaction between the jet and target, which can be adopted to evaluate jet penetration capability. The present study analyzes the factors that influence jet performances and proves that SLM technology is well-adapted in the manufacturing of shaped charge liners.

scholarly journals The International Self-Report Delinquency Study (ISRD3) in the Research Areas of the Białystok School of Criminology

2020 ◽  
Vol 20 (2) ◽  
pp. 349-369
Author(s):  
Ewa Guzik-Makaruk ◽  
Marta Dąbrowska
Keyword(s):  
Research Work ◽  
Self Report ◽  
Added Value ◽  
Age Group ◽  
Research Areas ◽  
Wide Range ◽  
Second Year ◽  
The University ◽  
Local Levels ◽  
Collaboration Agreement

On March 24, 2017, the Faculty of Law of the University of Białystok entered into a collaboration agreement with the Central Coordinating Team of the International Self-Report Delinquency Study (ISRD). Te Białystok School of Criminology is currently the only Polish representative participating in ISRD3. Te ISRD study addresses a wide range of issues examined by the Białystok School of Criminology, which launched its research work in 1994. The Białystok School of Criminology conducted its contribution to the ISRD3 research project in June 2017, in Białystok and Rzeszów, two Polish cities, regional capitals of their respective voivodeships. Each of these cities has a population of approximately half a million. The survey was conducted among pupils in their sixth year at a Polish primary (elementary) school (i.e. aged 12+) and in their first or second year at a Polish middle school (the 14+-16+ age group). In addition to the standard content prepared by the ISRD3 CCT, respondents filled in a questionnaire with questions intended to identify local levels of risks such as grooming or sexting. The results of the Polish ISRD3 study will help to diagnose various risks and will be compared to the results obtained in other countries participating in the project. The project’s added value will be the opportunity to develop appropriate preventive and educational programs for the schools in Białystok and Rzeszów which took part in the survey

scholarly journals Study on the Interference Process of Liquid Radial Reflux on the Stability of a Shaped Charge Jet

2021 ◽  
Vol 11 (17) ◽  
pp. 8044
Author(s):  
Youer Cai ◽  
Xudong Zu ◽  
Yaping Tan ◽  
Zhengxiang Huang
Keyword(s):  
Theoretical Analysis ◽  
Composite Structure ◽  
High Speed ◽  
Side Wall ◽  
Shaped Charge ◽  
Bottom Plate ◽  
Depth Of Penetration ◽  
X Ray ◽  
Shaped Charge Jet ◽  
Filled Composite

The process of liquid radial reflux interference during jet penetration in a liquid-filled composite structure is divided in this study into three stages: bottom plate reflection interference, side-wall reflection interference, and side-wall secondary reflection interference. The calculation model of the velocity interval of the disturbed jet and the residual penetration depth of the jet has been established through theoretical analysis. Results show that the liquid-filled composite structure can interfere with the high-speed section of the shaped charge jet. The accuracy of the theoretical analysis in this paper has been verified through numerical simulation, X-ray, and depth-of-penetration experiments. Among the results, those of the X-ray experiment show that the liquid-filled composite structure has interference on the tip of the shaped charge jet, which provides a possibility for the application of the liquid-filled composite structure to ammunition safety and other extreme cases.

scholarly journals Numerical Analysis and Experimental Test for the Development of a Small Shaped Charge

2021 ◽  
Vol 11 (6) ◽  
pp. 2578
Author(s):  
Piotr Malesa ◽  
Grzegorz Sławiński ◽  
Karolina Pęcherzewska
Keyword(s):  
Structural Damage ◽  
High Efficiency ◽  
High Strength ◽  
Shaped Charge ◽  
Military Industry ◽  
Wide Range ◽  
The Subject ◽  
Universal Constructions ◽  
A Charge ◽  
The Military

Currently, shaped charges are widely used in many fields of science and industry. Due to the high efficiency of piercing materials with high strength and hardness, shaped charges are commonly used in mining, military and for structural damage. The main application area of shaped charges is the military industry, where they are used in missiles with warheads (torpedoes, rocket launchers) and for piercing vehicle armor or bunker walls. When analyzing the existing solutions of shaped charges, one can find many typical solutions designed for specific applications. However, there are no universal constructions which, after appropriate regulation, will fulfil their role in a wide range of applications. The subject of this article is a new solution for a shaped charge that is characterized by compact dimensions and a short preparation time. This article presents the results of experimental research and the numerical analyses of such a charge.

Piezoelectric β-polymorph formation of new textiles by surface modification with coating process based on interfacial interaction on the conformational variation of poly (vinylidene fluoride) (PVDF) chains

2020 ◽  
Vol 91 (3) ◽  
pp. 31301
Author(s):  
Nabil Chakhchaoui ◽  
Rida Farhan ◽  
Meriem Boutaldat ◽  
Marwane Rouway ◽  
Adil Eddiai ◽  
...  
Keyword(s):  
High Efficiency ◽  
Vinylidene Fluoride ◽  
Research Work ◽  
Research Area ◽  
Interfacial Interaction ◽  
Tetraethyl Orthosilicate ◽  
Poly Vinylidene Fluoride ◽  
Carbon Nanofillers ◽  
The Impact ◽  
Advanced Applications

Novel textiles have received a lot of attention from researchers in the last decade due to some of their unique features. The introduction of intelligent materials into textile structures offers an opportunity to develop multifunctional textiles, such as sensing, reacting, conducting electricity and performing energy conversion operations. In this research work nanocomposite-based highly piezoelectric and electroactive β-phase new textile has been developed using the pad-dry-cure method. The deposition of poly (vinylidene fluoride) (PVDF) − carbon nanofillers (CNF) − tetraethyl orthosilicate (TEOS), Si(OCH2CH3)4 was acquired on a treated textile substrate using coating technique followed by evaporation to transform the passive (non-functional) textile into a dynamic textile with an enhanced piezoelectric β-phase. The aim of the study is the investigation of the impact the coating of textile via piezoelectric nanocomposites based PVDF-CNF (by optimizing piezoelectric crystalline phase). The chemical composition of CT/PVDF-CNC-TEOS textile was detected by qualitative elemental analysis (SEM/EDX). The added of 0.5% of CNF during the process provides material textiles with a piezoelectric β-phase of up to 50% has been measured by FTIR experiments. These results indicated that CNF has high efficiency in transforming the phase α introduced in the unloaded PVDF, to the β-phase in the case of nanocomposites. Consequently, this fabricated new textile exhibits glorious piezoelectric β-phase even with relatively low coating content of PVDF-CNF-TEOS. The study demonstrates that the pad-dry-cure method can potentially be used for the development of piezoelectric nanocomposite-coated wearable new textiles for sensors and energy harvesting applications. We believe that our study may inspire the research area for future advanced applications.

Justification of the need to improve the legal, regulatory and methodological framework for the spread of parasitic infections in the provision of medical care

2020 ◽  
Vol 99 (5) ◽  
pp. 493-497
Author(s):  
M. M. Aslanova ◽  
T. V. Gololobova ◽  
K. Yu. Kuznetsova ◽  
Tamari R. Maniya ◽  
D. V. Rakitina ◽  
...  
Keyword(s):  
Medical Care ◽  
Research Work ◽  
Hospital Environment ◽  
Parasitic Infections ◽  
Infusion Therapy ◽  
Methodological Framework ◽  
Production Environment ◽  
Medical Institutions ◽  
Medical Network ◽  
Wide Range

Introduction. The purpose of our work was to justify the need to improve the legislative, regulatory and methodological framework and preventative measures in relation to the spread of parasitic infections in the provision of medical care. There is a wide range of pathogens of parasitic infestations that are transmitted to humans through various medical manipulations and interventions carried out in various medical institutions. Contaminated care items and furnishings, medical instruments and equipment, solutions for infusion therapy, medical personnel’s clothing and hands, reusable medical products, drinking water, bedding, suture and dressing materials can serve as a major factor in the spread of parasitic infections in the provision of medical care. Purpose of research is the study of the structure and SMP of parasitic origin, circulating on the objects of the production environment in multi-profile medical and preventive institutions of stationary type in order to prevent the occurrence of their spread within medical institutions. Material and methods. The material for the study was flushes taken from the production environment in 3 multi-profile treatment and prevention institutions of inpatient type: a multi-specialty hospital, a maternity hospital and a hospital specializing in the treatment of patients with intestinal diseases for the eggs of worms and cysts of pathogenic protozoa. Results. During the 2-year monitoring of medical preventive institutions, a landscape of parasitic contamination was found to be obtained from the flushes taken from the production environment objects in the premises surveyed as part of the research work. Discussions. In the course of research, the risk of developing ISMP of parasitic origin was found to be determined by the degree of epidemiological safety of the hospital environment, the number and invasiveness of treatment and diagnostic manipulations and various medical technologies. Conclusion. It is necessary to conduct an expert assessment of regulatory and methodological documents in the field of epidemiological surveillance and sanitary and hygienic measures for the prevention of medical aid related infections of parasitic origin, to optimize the regulatory and methodological base, to develop a number of preventive measures aimed at stopping the spread of parasitic infections in the medical network.

Synthesis of Elaborate Benzofuran-2-Carboxamide Derivatives Through a Combination of 8-Aminoquinoline Directed C–H Arylations and Transamidations

2019 ◽  
Author(s):  
Michael Oschmann ◽  
Linus Johansson Holm ◽  
Oscar Verho
Keyword(s):  
Small Molecule ◽  
High Efficiency ◽  
Synthetic Strategy ◽  
Small Molecule Screening ◽  
Physiological Properties ◽  
Wide Range ◽  
Directing Group ◽  
Synthetic Sequence

Benzofurans are everywhere in nature and they have been extensively studied by medicinal chemists over the years because of their chemotherapeutic and physiological properties. Herein, we describe a strategy that can be used to access elaborate benzo-2-carboxamide derivatives, which involves a synthetic sequence of 8-aminoquinoline directed C–H arylations followed by transamidations. For the directed C–H arylations, Pd catalysis was used to install a wide range of aryl and heteroaryl substituents at the C3 position of the benzofuran scaffold in high efficiency. Directing group cleavage and further diversification of the C3-arylated benzofuran products were then achieved in a single synthetic operation through the utilization of a two-step transamidation protocol. By bocylating the 8-aminoquinoline amide moiety of these products, it proved possible to activate them towards aminolysis with different amine nucleophiles. Interestingly, this aminolysis reaction was found to proceed efficiently without the need of any additional catalyst or additive. Given the high efficiency and modularity of this synthetic strategy, it constitute a very attractive approach for generating structurally-diverse collections of benzofuran derivatives for small molecule screening.

To the 70th anniversary of World Meteorological Organization. Scientific and technical cooperation of Hydrometeorological Center of the USSR/Russia in the Programs of World Meteorological Organization

2020 ◽  
pp. 117-138
Author(s):  
S.V. Borshch ◽  
◽  
R.M. Vil’fand ◽  
D.B. Kiktev ◽  
V.M. Khan ◽  
...  
Keyword(s):  
Environmental Monitoring ◽  
High Efficiency ◽  
World Meteorological Organization ◽  
70Th Anniversary ◽  
Technical Level ◽  
Technical Cooperation ◽  
Wide Range

The paper presents the summary and results of long-term and multi-faceted experience of international scientific and technical cooperation of Hydrometeorological Center of Russia in the field of hydrometeorology and environmental monitoring within the framework of WMO programs, which indicates its high efficiency in performing a wide range of works at a high scientific and technical level. Keywords: World Meteorological Organization, major WMO programs, representatives of Hydrometeorological Center of Russia in WMO

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