Experimental Study on the Shock Consolidation of Ti+Si Powders

2018 ◽  
Vol 910 ◽  
pp. 3-8
Author(s):  
Nai Fu Cui ◽  
Peng Wan Chen ◽  
Chun Xiao Xu
Keyword(s):  
Experimental Study ◽  
Detonation Velocity ◽  
Shock Loading ◽  
Hydraulic Press ◽  
Shock Pressure ◽  
Reaction Threshold ◽  
Compaction Process ◽  
Experimental Conditions ◽  
Explosive Compaction ◽  
Shock Consolidation

The research on the explosive compaction of reactive powders is a hot issue. In this work, unreacted Ti-Si block with high compactness has been successfully fabricated under explosive-driven compaction process. The precursors of Ti-Si powder with different stoichiometric ratios undergo pre-compaction shaping by hydraulic press and then shock loading treatment by using low-detonation-velocity explosives of varying loading conditions. The results show that the chemical reaction between Ti and Si powders are partly initiated even under low detonation pressures, indicating extremely low reaction threshold in the Ti-Si system. Meanwhile, optimal experimental conditions are displayed as the initial pressing compactness degree of 61%, and shock pressure of 11GPa. A compactness of 97% is achieved in the synthesized Ti-Si block with the lowest reactivity.

Comparison of Recovery and Recrystallization in Stainless Steel Following Plane-Wave Shock Loading and Explosive Forming

1970 ◽  
Vol 28 ◽  
pp. 428-429 ◽  
Author(s):  
J. A. Korbonski ◽  
L. E. Murr
Keyword(s):  
Stainless Steel ◽  
Shock Loading ◽  
Pressure Pulse ◽  
Shock Pressure ◽  
304 Stainless Steel ◽  
Strain Rates ◽  
Two Dimensional ◽  
Aisi 304 Stainless Steel ◽  
Aisi 304 ◽  
Explosive Forming

Comparison of recovery rates in materials deformed by a unidimensional and two dimensional strains at strain rates in excess of 104 sec.−1 was performed on AISI 304 Stainless Steel. A number of unidirectionally strained foil samples were deformed by shock waves at graduated pressure levels as described by Murr and Grace. The two dimensionally strained foil samples were obtained from radially expanded cylinders by a constant shock pressure pulse and graduated strain as described by Foitz, et al.

Effects of Provocation on Emotions and Aggression: An Experimental Study with Aggressive Children

2006 ◽  
Vol 65 (2) ◽  
pp. 117-124 ◽  
Author(s):  
Christina Stadler ◽  
Sonja Rohrmann ◽  
Sibylle Steuber ◽  
Fritz Poustka
Keyword(s):  
Experimental Study ◽  
Positive Emotions ◽  
Skin Conductance Level ◽  
Physiological Measures ◽  
Competitive Reaction ◽  
Experimental Conditions ◽  
Conduct Disordered ◽  
Physiological Variables ◽  
Aggressive Children ◽  
Conductance Level

In this study, the effects of an experimental-induced provocation on emotions and aggression were examined in 34 aggressive conduct-disordered children using a competitive reaction time paradigm. Two experimental conditions were created, an increasing provocation and a low constant provocation condition. Self-rated anger was assessed directly after provocation on a 5-point-visual scale. In addition, negative and positive emotions as well as physiological measures (heart rate and skin conductance level) were measured at baseline and after provocation. Results revealed that participants’ aggressive behaviour and subjective emotions differed as a function of the opponent’s level of provocation. Concerning physiological parameters, no significant differences were found between the experimental conditions. These results suggest that affective, but not physiological variables characterize reactive aggression in conduct-disordered children.

The Experimental Study on the Fire Suppression Effectiveness of Water Mist with the FeCl2 Additives

2013 ◽  
Vol 790 ◽  
pp. 53-56
Author(s):  
Chen Jian ◽  
Xu Yan Ying ◽  
Wang Na
Keyword(s):  
Experimental Study ◽  
Fire Suppression ◽  
Water Mist ◽  
Experimental Results ◽  
Additive Concentration ◽  
Experimental Conditions ◽  
Fire Source ◽  
Fire Extinguishing ◽  
Nozzle Position

This paper presents an experimental study of fire suppression effectiveness with water mist containing FeCl2 additives.The investigation focuses on suppression effectiveness under various FeCl2 additives concentrations,working pressures and nozzle different height above the fire source . The experimental results show that: there is a significant impact on fire suppression effectiveness when adding FeCl2 to water mist. There is an optimum additive concentration of extinguishing fire, corresponding to the shortest extinguishing time, the least amount of water, the highest efficiency of extinguishing fire. The nozzle working pressures and nozzle position have effect on the performance of the water mist extinguishing: the greater the pressure is, the shorter water mist fire extinguishing time is. Under the same experimental conditions, the closer the water mist nozzles are to the oil pan, the shorter extinguishing time is.

Numerical and experimental study of the second ejection from a grooved tin surface under laser-driven shock loading

2021 ◽  
pp. 104135
Author(s):  
Wenbin Liu ◽  
Tao Xi ◽  
Anmin He ◽  
Tingting Zhou ◽  
Jianting Xin ◽  
...  
Keyword(s):  
Experimental Study ◽  
Shock Loading

Convergent and Discriminant Relationships between Factor Matrices of Motor Performance and Arousal Data

1976 ◽  
Vol 42 (2) ◽  
pp. 459-465 ◽  
Author(s):  
Hardo Sorgatz
Keyword(s):  
Experimental Study ◽  
Motor Learning ◽  
Principal Components ◽  
Motor Performance ◽  
Performance Data ◽  
Similarity Coefficients ◽  
Experimental Conditions ◽  
Meaningful Information ◽  
Data Similarity ◽  
Maximum Similarity

An experimental study was conducted to demonstrate the value of a procedure for analyzing motor performance data. A sample of 156 subjects practiced on two instruments for motor learning while arousal data were recorded. Each set of data was submitted to an analysis of principal components and four components resulted for each set of data. Similarity coefficients were calculated for pairs of component matrices after rotation to maximum similarity. The similarity coefficients exhibit a consistent pattern which provides meaningful information concerning influence of experimental conditions on performance data.

scholarly journals Experimental study of gene flow between wild and cultivated Pennisetum glaucum

1997 ◽  
Vol 75 (6) ◽  
pp. 925-931 ◽  
Author(s):  
J. -F. Renno ◽  
T. Winkel ◽  
F. Bonnefous ◽  
G. Bezançon
Keyword(s):  
Experimental Study ◽  
Gene Flow ◽  
Pearl Millet ◽  
Pennisetum Glaucum ◽  
Morphological Differentiation ◽  
Time Dependent ◽  
Natural Conditions ◽  
Experimental Conditions ◽  
Viable Seeds ◽  
Wild Sample

Under natural conditions, wild and cultivated pearl millet, Pennisetum glaucum (L.) R.Br., exchanged genes for millenia and, nevertheless, maintain high morphological differentiation. Under experimental conditions in the Sahel, hybridization between wild and cultivated pearl millet was measured using isozymic markers and interpreted in relation to the phenology of the plants. Gene flows were asymmetric, engendering 8% of hybrids in the progeny of the wild phenotype, 45% in that of the cultivated phenotype, and 39% in that of the intermediate "shibra" phenotype; these last two phenotypes constitute the sample of cultivated pearl millet. The proportion of hybrids in the progeny of the wild sample was time dependent during the flowering phase of cultivated pearl millet. The proportion of hybrids produced by the cultivated pearl millet was not time dependent. In the seeds produced by the cultivated phenotype along its reproductive phase, the proportion of viable seeds was negatively correlated with the frequency of hybrids. Likewise, the speed of germination of seeds produced by the cultivated or the shibra phenotypes was negatively correlated with the frequency of the hybrids that they contained. The effects of balancing among genetic intermixing, isolation and reproduction barriers, and differential anthropic and natural selection pressures are discussed to better understand the evolution and the maintenance of the polymorphism of Pennisetum glaucum. Key words: pearl millet, wild pearl millet, Pennisetum glaucum, gene flow, domestication, hybrid.

scholarly journals Pressure Hull Analysis under Shock Loading

2008 ◽  
Vol 15 (1) ◽  
pp. 19-32 ◽  
Author(s):  
Ya-Jung Lee ◽  
Chia-Hao Hsu ◽  
Chien-Hua Huang
Keyword(s):  
Shock Wave ◽  
Pressure Distribution ◽  
High Performance ◽  
Shock Loading ◽  
Shock Pressure ◽  
Structural Arrangement ◽  
Simulation Efficiency ◽  
Long Run ◽  
Underwater Shock ◽  
Initial Shock

The hull of high performance submarines must resist underwater shock loading due to exploding torpedoes or depth bombs. An underwater shock involving an initial shock wave and successive bubble pulsating waves is so complex that a theoretical technique for deriving shock pressure distribution is required for improving simulation efficiency. Complete shock loading is obtained theoretically in this work, and responses of a submarine pressure hull are calculated using ABAQUS USA (Underwater Shock Analysis) codes. In the long run, this deflection and stress data will assist in examining the structural arrangement of the submarine pressure hull.

scholarly journals Experimental study of the European river lamprey Lampetra fluviatilis (L.) downstream migrating smolts rheoreaction under various illuminations

2019 ◽  
Vol 487 (4) ◽  
pp. 469-472
Author(s):  
A. O. Zvezdin ◽  
D. S. Pavlov ◽  
I. A. Tsimbalov ◽  
A. V. Kucheryavyy
Keyword(s):  
Experimental Study ◽  
Active Form ◽  
Downstream Migration ◽  
Natural Conditions ◽  
Experimental Conditions ◽  
Lampetra Fluviatilis ◽  
River Lamprey

Rheoreaction of the downstream migrating smolts of the European river lamprey was studied in the experimental conditions at illuminations of day and night intensity. It was found that at the daytime the smolts are mostly dormant and if move downstream then in active-passive form (with the head against the stream, and their speed going beyond the velocity). This data is well within the findings on the night downstream migration of the smolts during the 24 h period in natural conditions. Thus, the downstream migration of the smolts has an active form.

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