scholarly journals Research on the Energy Release Characteristics of Six Kinds of Reactive Materials

Materials ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 3940 ◽  
Author(s):  
Xianwen Ran ◽  
Liangliang Ding ◽  
Jingyuan Zhou ◽  
Wenhui Tang
Keyword(s):  
Energy Release ◽  
The Self ◽  
Weight System ◽  
Test Device ◽  
Reactive Material ◽  
Reactive Materials ◽  
Release Test ◽  
Penetration Ability ◽  
Speed Up ◽  
The Impact

Currently, PTFE/Al is widely used in the reactive fragmentation warhead. However, for the same explosive yield, the reactive fragments usually have a smaller damage-radius than the inert fragments because PTFE/Al has a poor penetration ability and needs an impact-speed up to 1000 m/s to stimulate its chemical reaction. To enhance the damage power of reactive fragments, six kinds of reactive materials (PTFE/Al, PTFE/B, PTFE/Si, PTFE/Al/B, PTFE/Al/Si, and PTFE/Al/CuO) based on PTFE were designed and studied. Through the drop weight system and the self-designed energy release test device, qualitative and quantitative analysis of the energy release ability of six kinds of reactive materials were carried out. The qualitative analysis results indicate that the reactions of PTFE/B and PTFE/Si are weak under the impact of drop hammer with only a very weak fire light produced, while the reactions of PTFE/Al, PTFE/Al/B, PTFE/Al/Si, and PTFE/Al/CuO are relatively intense, and the reaction of PTFE/Al/Si is the most intense. Through the self-designed energy release test device, the energy release ability of the reactive material was quantitatively compared and analyzed. The results show that the energy release ability of the four formulations were as follows: PTFE/Al/Si > PTFE/Al/CuO > PTFE/Al/B > PTFE/Al. Therefore, it can be concluded that the PTFE/Al/Si formulation is a new reactive material with strong energy release ability, which can be a new choice for reactive fragment.

scholarly journals Modelling on Shock-Induced Energy Release Behavior of Reactive Materials considering Mechanical-Thermal-Chemical Coupled Effect

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Baoyue Guo ◽  
Kerong Ren ◽  
Zhibin Li ◽  
Rong Chen
Keyword(s):  
Numerical Simulation ◽  
Energy Release ◽  
Simulation Approach ◽  
Release Behavior ◽  
Reactive Material ◽  
Reactive Materials ◽  
Coupled Effect ◽  
Macro Scale ◽  
The Military ◽  
The Impact

Reactive material (RM) is a new type of energetic material, which is widely used in the military technology fields such as fragmentation warheads and shaped charge warheads. Violent chemical reactions take place in the impact process of reactive materials, and how to realize the macro numerical simulation of shock-induced energy release behavior of reactive materials is one of the most urgent problems to be solved for its future military applications. In this study, a numerical simulation approach and procedure is proposed, which can simulate the shock-induced energy release behavior of reactive materials on a macro scale. Firstly, program implementation of the mechanical-thermal-chemical coupled effect model for RM is realized in the second-development interface of LS-DYNA software. Then, the adaptive simulated annealing algorithm is used to fit the chemical reaction kinetic parameters of RM using the direct ballistics test data. Finally, the simulation calculation of the fragment penetrating upon steel plate is carried out to expand the applicability of the numerical simulation approach proposed in this study. The results show that the numerical simulation approach proposed in this study can reproduce the results of the direct ballistics test more accurately, which assumes practical significance for the engineering application of reactive materials in the military field in the future.

scholarly journals Impact Energy Release Characteristics of PTFE/Al/CuO Reactive Materials Measured by a New Energy Release Testing Device

Polymers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 149 ◽  
Author(s):  
Liangliang Ding ◽  
Jingyuan Zhou ◽  
Wenhui Tang ◽  
Xianwen Ran ◽  
Yuxuan Hu
Keyword(s):  
Energy Release Rate ◽  
Energy Release ◽  
Release Rate ◽  
Time History ◽  
Testing Device ◽  
Reactive Material ◽  
Reactive Materials ◽  
Pressure Time ◽  
New Energy ◽  
Release Testing

Metal/polymer reactive materials have been studied and applied in a wide range of ways in recent years. This type of material is insensitive under normal conditions but reacts violently and releases a large amount of chemical energy under high-speed impact or high strain rate loading conditions. Compared with conventional explosives, it has better mechanical properties, and its unit mass energy is several times that of TNT. In this paper, PTFE/Al/CuO reactive materials are the main research objects, and we assess the impact energy release abilities of this type of reactive material through experimental research. To this end, eight sets of material formulations are designed, and the effects of particle size, the ratio of PTFE/Al and Al/CuO materials, and sintering on the energy release ability of the reactive materials are investigated. All experiments are carried out based on a self-designed new energy release testing device. The experimental device can measure the pressure time history curve generated by the reactive materials, and the rationality of the pressure time history curve can also be verified by the displacement time curve of the piston. The results show that with an increase in the Al/CuO thermite content, the energy release rate of the reactive material clearly increases, which is attributed to the reaction threshold of Al/CuO being low and because the heat generated can promote the reaction of PTFE/Al. The energy release rate of the nano-scale reactive materials is higher than that of the micron-scale reactive materials because the reduction in particle size results in a larger specific surface area. Thus, the energy required for ignition is lower. The energy release rate of sintered reactive materials is higher than that of unsintered reactive materials, which can be explained by the interfacial area between Al particles and PTFE particles in sintered reactive materials being larger, which makes the reaction more sufficient. The self-designed energy release testing device for the reactive materials and the conclusions obtained in this paper have clear significance for guiding engineering applications.

scholarly journals Modeling of Impact Energy Release of PTFE/Al Reactive Material

2021 ◽  
Vol 11 (19) ◽  
pp. 8910
Author(s):  
Xuan Zou ◽  
Jingyuan Zhou ◽  
Wenhui Tang ◽  
Yiting Wu ◽  
Pengwan Chen ◽  
...  
Keyword(s):  
Energy Release ◽  
Impact Energy ◽  
Chemical Kinetic ◽  
State Equation ◽  
Release Behavior ◽  
Hugoniot Curve ◽  
Reactive Material ◽  
Simulation Parameters ◽  
The Hill ◽  
The Impact

Many scholars have used experimental research methods to conduct extensive research on the impact energy release behavior of Polytetrafluoroethylene(PTFE)/Al reactive materials. However, in numerical simulation, PTFE/Al still lacks the calculation parameters of impact energy release behavior. In order to obtain the simulation parameters of PTFE/Al impact ignition, the Hill mixture law was used to calculate the material parameters of PTFE/Al (mass ratio 73.5/26.5), and according to the Hugoniot curve of PTFE/Al and the γ state equation, the JWL equation of state of a PTFE/Al unreacted substance and reaction product was fitted with a genetic algorithm. According to the PTFE/Al impact energy release experiment, the parameters of the PTFE/Al chemical kinetic equation were determined, and the parameters of the trinomial reaction rate equation were fitted. The obtained parameters were used in the simulation calculation in LS-dyna to predict the damage of the aluminum target plate under the impact of the PTFE/Al reactive fragments.

Self-Compassion and Quality of Life in Adults Who Stutter

2020 ◽  
Vol 29 (4) ◽  
pp. 2097-2108
Author(s):  
Robyn L. Croft ◽  
Courtney T. Byrd
Keyword(s):  
Quality Of Life ◽  
Social Connectedness ◽  
The Self ◽  
Future Research ◽  
Self Compassion ◽  
Adults Who Stutter ◽  
And Gender ◽  
Relationship Of ◽  
The Impact

Purpose The purpose of this study was to identify levels of self-compassion in adults who do and do not stutter and to determine whether self-compassion predicts the impact of stuttering on quality of life in adults who stutter. Method Participants included 140 adults who do and do not stutter matched for age and gender. All participants completed the Self-Compassion Scale. Adults who stutter also completed the Overall Assessment of the Speaker's Experience of Stuttering. Data were analyzed for self-compassion differences between and within adults who do and do not stutter and to predict self-compassion on quality of life in adults who stutter. Results Adults who do and do not stutter exhibited no significant differences in total self-compassion, regardless of participant gender. A simple linear regression of the total self-compassion score and total Overall Assessment of the Speaker's Experience of Stuttering score showed a significant, negative linear relationship of self-compassion predicting the impact of stuttering on quality of life. Conclusions Data suggest that higher levels of self-kindness, mindfulness, and social connectedness (i.e., self-compassion) are related to reduced negative reactions to stuttering, an increased participation in daily communication situations, and an improved overall quality of life. Future research should replicate current findings and identify moderators of the self-compassion–quality of life relationship.

Effect of Parental Modernity on Rejection Sensitivity and Self-Esteem of Adolescents

2016 ◽  
Vol 3 (2) ◽  
Author(s):  
Ritu ◽  
Madhu Anand
Keyword(s):  
Social Development ◽  
Rejection Sensitivity ◽  
Self Esteem ◽  
The Self ◽  
Negatively Associated ◽  
Individual Modernity ◽  
The Impact ◽  
The Relationship

Parental Modernity is an important aspect for the psycho-social development of the child. The present study aims to study the effect of parental modernity on rejection sensitivity and self-esteem of adolescents and the relationship between rejection sensitivity and self-esteem. The research is carried out on a sample of 240 parents (including 120 fathers and 120 mothers) and their 120 children. For observing the impact of modernity of parents on their children, Individual Modernity Scale was used and administered on father and mother. Rejection Sensitivity Questionnaire and Self-Esteem Inventory were used to measure the rejection sensitivity and self-esteem of children (age ranges from 14 to 19 years). The results suggest that parental modernity has an effect on the rejection sensitivity and personally perceived self of the self – esteem of adolescents. Furthermore, the rejection sensitivity has been found negatively associated with self-esteem.

Fluxus and the Absurd (1961–62)

2017 ◽  
Author(s):  
Benjamin R. Levy
Keyword(s):  
Second Life ◽  
The Self ◽  
Major Work ◽  
The Future ◽  
To Come ◽  
The Impact

After John Cage’s 1958 Darmstadt lectures, many European composers developed an interest in absurdity and artistic provocation. Although Ligeti’s fascination with Cage and his association with the Fluxus group was brief, the impact it had on his composition was palpable and lasting. A set of conceptual works, The Future of Music, Trois Bagatelles, and Poème symphonique for one hundred metronomes, fall clearly into the Fluxus model, even as the last has taken on a second life as a serious work. This spirit, however, can also be seen in the self-satire of Fragment and the drama and irony of Volumina, Aventures, and Nouvelles Aventures. The sketches for Aventures not only show the composer channeling this humor into a major work but also prove to be a fascinating repository of ideas that Ligeti would reuse in the years to come.

scholarly journals Research on the Ignition Height and Reaction Flame Temperature of PTFE/Al/Si/CuO with Different Mass Ratios of PTFE/Si

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3464
Author(s):  
Xuan Zou ◽  
Jingyuan Zhou ◽  
Xianwen Ran ◽  
Yiting Wu ◽  
Ping Liu ◽  
...  
Keyword(s):  
Energy Release ◽  
High Speed ◽  
Flame Temperature ◽  
Sintering Process ◽  
Release Process ◽  
Reactive Material ◽  
Temperature Changes ◽  
Release Capacity ◽  
Mass Ratios ◽  
The Relationship

Recent studies have shown that the energy release capacity of Polytetrafluoroethylene (PTFE)/Al with Si, and CuO, respectively, is higher than that of PTFE/Al. PTFE/Al/Si/CuO reactive materials with four proportions of PTFE/Si were designed by the molding–sintering process to study the influence of different PTFE/Si mass ratios on energy release. A drop hammer was selected for igniting the specimens, and the high-speed camera and spectrometer systems were used to record the energy release process and the flame spectrum, respectively. The ignition height of the reactive material was obtained by fitting the relationship between the flame duration and the drop height. It was found that the ignition height of PTFE/Al/Si/CuO containing 20% PTFE/Si is 48.27 cm, which is the lowest compared to the ignition height of other Si/PTFE ratios of PTFE/Al/Si/CuO; the flame temperature was calculated from the flame spectrum. It was found that flame temperature changes little for the same reactive material at different drop heights. Compared with the flame temperature of PTFE/Al/Si/CuO with four mass ratios, it was found that the flame temperature of PTFE/Al/Si/CuO with 20% PTFE/Si is the highest, which is 2589 K. The results show that PTFE/Al/Si/CuO containing 20% PTFE/Si is easier to be ignited and has a stronger temperature destruction effect.

scholarly journals The “Christology” of Bely the Anthroposophist: Andrei Bely, Rudolf Steiner, and the Apostle Paul

Religions ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 519
Author(s):  
Monika Spivak
Keyword(s):  
The Self ◽  
Apostle Paul ◽  
Rudolf Steiner ◽  
2 Corinthians ◽  
History Of ◽  
The Impact

The article focuses on R. Steiner’s perception of the Gospels and the impact of that view on Bely’s works. The latter had always valued Steiner’s lectures on Christ and the Fifth Gospel, the “Anthroposophic” (relating to the philosophy of human genesis, existence, and outcome) Gospel, the knowledge of which had been received in a visionary way. In addition, Bely was an esoteric follower of Steiner and often quoted from Apostle Paul’s 2 Corinthians, “Ye are our epistle written in our hearts, known and read of all men”. The citation occurs in Bely’s philosophical works (The History of the Formation of the Self-Conscious Soul, “Crisis of Consciousness”), autobiographic prose (Reminiscences of Steiner), the essay “Why I Became a Symbolist…”, and letters (to Ivanov-Razumnik and Fedor Gladkov). Bely’s own anthroposophic and esoteric ideas relating to the gospel sayings are also examined. The aim of the research is to show through the example of one quotation the specifics of Bely the Anthroposophist’s perception of Christian texts in general. This provides a methodological meaning for understanding other Biblical quotations and images in the works of Bely because anthroposophical Christology is also the key to their deciphering.

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