scholarly journals FABRIC FOR SINGLE SKIN TEXTILE WING

2019 ◽  
Vol 2019 ◽  
pp. 220-223
Author(s):  
Adrian SALISTEAN ◽  
Carmen MIHAI ◽  
Irina CRISTIAN ◽  
Daniela FARIMA ◽  
Cristina PIROI
Keyword(s):  
Mechanical Characteristics ◽  
Statistical Data ◽  
Breaking Strength ◽  
Air Permeability ◽  
Experimental Results ◽  
The Other ◽  
Wing Design ◽  
Shape Stability ◽  
International Testing

The fabrics used to make parachutes and paragliders must have the several specific characteristics: the mass of fabric per unit of surface must be low while the other physical- mechanical characteristics (the axial breaking strength load, the relative and absolute elongation, the tear resistance of the fabric and the assemblies, air permeability) must be at a maximum. The paper deals with the analysis of qualitative aspects of several parachute fabrics that are used as a baseline in the development of a novel fabric. The results of experiments have materialized in statistical data, diagrams and graphs and their interpretation leads to the determination of the fabric variant that best meets the requirements of the destination. The destination is a patent pending inflatable wing design that utilizes a single skin construction and solid reinforcements in the sewing for shape stability. It is worth noting that the experimental results were compared with values indicated in specific international testing norms.

scholarly journals Textile wing fabric for emergency response UAS

2020 ◽  
Vol 71 (04) ◽  
pp. 321-326
Author(s):  
ADRIAN SĂLIȘTEAN ◽  
CARMEN MIHAI
Keyword(s):  
Emergency Response ◽  
Mechanical Characteristics ◽  
Statistical Data ◽  
Breaking Strength ◽  
Air Permeability ◽  
Experimental Results ◽  
The Other ◽  
Shape Stability ◽  
International Testing

The fabrics used to manufacture parachutes and paragliders must have several specific characteristics: the mass of fabric per unit of surface must be low while the other physical-mechanical characteristics (the axial breaking strength load, the relative and absolute elongation, the tear resistance of the fabric and the assemblies, air permeability) must have high values. The paper deals with the analysis of qualitative aspects of several parachute fabrics that are used as a baseline in the development of a novel fabric. The results of experiments have materialized in statistical data, diagrams and graphs and their interpretation leads to the determination of the fabric variant that best meets the requirements of the destination. The destination is a patent pending inflatable wing design that utilizes a single skin construction and solid reinforcements in the sewing for shape stability. It is worth noting that the experimental results were compared with values indicated in specific international testing norms.

Quantitative Determimatioh of Sulfur, Chlorine, Potassium, Calcium, Scandium and Titanium in Aqueous Solutions by Radioisotopic Excited Fluorescent Spectrometer and by Conventional X-Ray Spectrometer

1970 ◽  
Vol 14 ◽  
pp. 102-126 ◽  
Author(s):  
Frank L. Chan ◽  
W. Barclay Jones
Keyword(s):  
Particle Size ◽  
Aqueous Solutions ◽  
Experimental Results ◽  
The Other ◽  
X Rays ◽  
Helium Atmosphere ◽  
X Ray ◽  
Effect Of Particle Size ◽  
The One

AbstractAn x-ray spectrometer with experimental results is herewith described using a radiosotope source Fe55 having a halflife of 2.6 years. As a result of the disintegration, the managanese x-rays are capable of exciting fluorescent x-rays of such elements as sulfur, chlorine, potassium, calcium, scandium and titanium in aqueous solutions. These elements with the Ka wavelengths ranging from 5.3729 Å to 2.7496 Å may be designated as between the very soft x-rays on the one hand and the hard x-rays on the other. The x-ray spectrometer presently described has achieved a resolution of 136 ev, FWHM.Simultaneously, these elements have also been quantitatively determined by conventional x-ray fluorescent spectrometers. Since one of the spectrometers is designed to operate in vacuum as well as in helium or air, determination of sulfur, potassium and calcium were carried out in vacuum. Determination of chlorine was carried out in a helium atmosphere, Calcium, scandium and titanium were determined in air with an air-path spectrometer.In the present study aqueous solutions containing these elements were used. The use of aqueous solutions has the inherent advantages of being homogeneous and free from effect of particle size.

Etude des mouvements de molécules linéaires en phase liquide par analyse du profil des bandes d'absorption infrarouge.: II. Bande v3 du sulfure de carbonyle

1972 ◽  
Vol 50 (2) ◽  
pp. 217-225 ◽  
Author(s):  
A. M. Bize ◽  
J. Soussen-Jacob ◽  
J. Vincent-Geisse ◽  
D. Legay ◽  
J. P. Perchard
Keyword(s):  
Potential Barrier ◽  
Correlation Functions ◽  
Carbonyl Sulfide ◽  
Experimental Results ◽  
The Other ◽  
Band Width ◽  
Saturated Hydrocarbons ◽  
Rotational Effect ◽  
The Mean

The band width and profile of v3 mode of carbonyl sulfide (OCS) dissolved in about 30 solvents have been examined. The study of temperature broadening permits the separation of the vibrational and rotational effects and the determination of the potential barrier to rotation. Correlation functions have been plotted from the experimental results; the mean squared torques acting on carbonyl sulfide in various solvents have been calculated from the second and the fourth moments. The obtained results bear evidence of a dominant rotational effect for solutions in saturated hydrocarbons while, for the other solvents, vibrational broadening proves important.

Pole-Vaulting: Identification of the Pole Local Bending Rigidities by an Updating Technique

2008 ◽  
Vol 24 (2) ◽  
pp. 140-148 ◽  
Author(s):  
Julien Morlier ◽  
Michel Mesnard ◽  
Mariano Cid
Keyword(s):  
Finite Element ◽  
Composite Material ◽  
Performance Improvement ◽  
Mechanical Characteristics ◽  
Dynamic Structure ◽  
Experimental Results ◽  
The Other ◽  
Finite Element Models ◽  
Model Sensitivity ◽  
Deflection Test

The development of composite material poles since 1960 has played a prominent part in performance improvement in pole-vaulting. Previous studies devoted to pole-vaulting models were based on constant mechanical characteristics. It is thus necessary to identify the local bending rigidities of the pole to build realistic pole-vaulting models. Updating methods developed for dynamic structure studies allow us to describe local mechanical characteristics. These methods are based on the comparison between experimental results and those determined numerically by finite element models. This study presents an adaptation of these methods to determine the local bending rigidities of the pole. The updating technique is validated by a deflection test of a homogeneous beam. Then, a study of the model sensitivity is carried out to investigate the procedure robustness. Finally, the updating method is applied to an old design pole and to a recent one. The results obtained vary greatly from one pole to the other; they highlight the evolutions in pole design.

De Haas – van Alphen effect and Fermi surface of the intermetallic compound PtSn

1970 ◽  
Vol 48 (10) ◽  
pp. 1151-1160 ◽  
Author(s):  
W. N. Cathey ◽  
P. T. Coleridge ◽  
J.-P. Jan
Keyword(s):  
Intermetallic Compound ◽  
Fermi Surface ◽  
Cross Sections ◽  
Experimental Results ◽  
The Other ◽  
Platinum Atom ◽  
Spin Splitting ◽  
Approximate Determination ◽  
Formula Unit

Extremal cross sections of the Fermi surface of the intermetallic compound PtSn (NiAs structure) have been determined by means of the de Haas – van Alphen effect. The Fermi surface proposed here is similar to that found in isostructural AuSn by Edwards et al. Several of the frequencies have been inverted to yield the profile of the corresponding sheets of the Fermi surface. An approximate determination of the dimensions of the other sheets shows that the observed Fermi surface encloses 4.60 ± 0.27 electrons per formula unit; this suggests that one or several sheets of the Fermi surface containing 0.6 d-band holes per platinum atom have remained undetected. Some cyclotron masses have been measured and to explain all the features of the experimental results, it is necessary to invoke spin splitting with a g factor different from 2, and to postulate magnetic breakdown.

scholarly journals Study of prestrain influence for the prediction of the necking occurrence

1999 ◽  
Vol 21 (1) ◽  
pp. 57-64
Author(s):  
Nguyen Nhat Thang
Keyword(s):  
Mild Steel ◽  
Steel Sheet ◽  
Mechanical Characteristics ◽  
Experimental Results ◽  
Forming Limit ◽  
Stress Diagram ◽  
Stress Curve ◽  
Limit Stress

This paper contains experimental results for mechanical characteristics of a mild steel sheet. The determination of the forming limit stress curve for solicitation along two direction is drawn. Study of pestraint influence from the limit stress diagram is presented.

Determination of the Recombination Processes in Copper Ternary Chalcopyrites by Phototransport Measurements

1996 ◽  
Vol 426 ◽  
Author(s):  
Y. Lubianmker ◽  
G. Bitton ◽  
I. Balberg ◽  
O. Resto ◽  
S. Z. Weisz
Keyword(s):  
Level Structure ◽  
Experimental Results ◽  
The Other ◽  
Recombination Level ◽  
Recombination Processes ◽  
General Recombination ◽  
Level Model ◽  
Ternary Chalcopyrites ◽  
Two Level Model

AbstractWe have measured the phototransport properties of CuGaSe2 films as a function of temperature. The simplest model which is consistent with all the experimental results consists of two recombination levels, one of which is donor-like and the other is acceptor-like. This model is similar to the symmetrical two-level model, which we have recently suggested for CuInS2 films. We thus conclude that this model, with slight variations, represents the general recombination level structure in all copper ternary chalcopyrites.

scholarly journals The determination of air-permeability of soils.

1960 ◽  
Vol 8 (2) ◽  
pp. 124-131 ◽  
Author(s):  
A.R.P. Janse ◽  
G.H. Bolt
Keyword(s):  
Pressure Gradient ◽  
Sandy Soil ◽  
Constant Pressure ◽  
Air Permeability ◽  
Experimental Results

An improved apparatus for determining air-permeability of soils at constant pressure gradient is described; its merits are discussed in the light of existing literature. Some experimental results obtained with a sandy soil under different tillage conditions are given and discussed. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Validation of a UV Spectrometric Method for the Assay of Tolfenamic Acid in Organic Solvents

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Sofia Ahmed ◽  
Nafeesa Mustaan ◽  
Muhammad Ali Sheraz ◽  
Syeda Ayesha Ahmed un Nabi ◽  
Iqbal Ahmad
Keyword(s):  
Organic Solvents ◽  
Statistical Data ◽  
Tolfenamic Acid ◽  
The Other ◽  
Spectrometric Method ◽  
Solution Stability ◽  
Solvent Interactions ◽  
Stock Solutions ◽  
Better Than

The present study has been carried out to validate a UV spectrometric method for the assay of tolfenamic acid (TA) in organic solvents. TA is insoluble in water; therefore, a total of thirteen commonly used organic solvents have been selected in which the drug is soluble. Fresh stock solutions of TA in each solvent in a concentration of 1 × 10−4 M (2.62 mg%) were prepared for the assay. The method has been validated according to the guideline of International Conference on Harmonization and parameters like linearity, range, accuracy, precision, sensitivity, and robustness have been studied. Although the method was found to be efficient for the determination of TA in all solvents on the basis of statistical data 1-octanol, followed by ethanol and methanol, was found to be comparatively better than the other studied solvents. No change in the stock solution stability of TA has been observed in each solvent for 24 hours stored either at room (25±1°C) or at refrigerated temperature (2–8°C). A shift in the absorption maxima has been observed for TA in various solvents indicating drug-solvent interactions. The studied method is simple, rapid, economical, accurate, and precise for the assay of TA in different organic solvents.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

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