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Tytuł:
The Influence of a Nanometric Layer with a High Refracting Index οn the Sensitivity οf the Difference Interferometer
Autorzy:
Gut, K.
Powiązania:
https://bibliotekanauki.pl/articles/1811550.pdf
Data publikacji:
2008-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
42.82.Et
07.07.Df
42.79.Pw
Opis:
Planar waveguides in which some range of the waveguide was modified by depositing on it a layer of some other dielectric, are called composite optical waveguides. Such a structure is based on a planar waveguide obtained by means of ion exchange $K^+-Na^+$ on glass, and covered by an adequately profiled dielectric layer. This kind of structure is of much interest due to considerable possibilities of taking measurements, which may contribute to a further development of the optoelectronic sensor. Especially required are sensor systems in chemistry, biochemistry, biotechnology, and others. Investigations on the properties of composite layers constitute a continuation of investigations concerning the construction of interferometers, which are very sensitive, cheap and easy to be produced.
Źródło:
Acta Physica Polonica A; 2008, 114, 6A; A-121-A-126
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stress sensitivity coefficient of a material in the range of high-cycle fatigue
Współczynnik wrażliwości naprężenia materiału w zakresie zmęczenia wysokocyklicznego
Autorzy:
Szala, G.
Powiązania:
https://bibliotekanauki.pl/articles/257994.pdf
Data publikacji:
2010
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Eksploatacji - Państwowy Instytut Badawczy
Tematy:
odporność na zmęczenie
charakterystyki dwuparametryczne
stal typu S355J0
fatigue life
two-parametric characteristics
S355J0 steel
Opis:
In the calculation of fatigue life of structural components that have been subjected in service conditions to stochastic load, load spectra in the form of sinusoidal cycles of different asymmetry can be observed. Cycle asymmetry is distinguished by the stress ratio R = Smin /Smax. In case of the load mentioned above, the R coefficient changes in broad boundaries from - ∞ to + ∞. In this work, the analysis of the material's stress sensitivity to cycle asymmetry of random load has been presented. In the references, analytical formulas for the fatigue strength range can be found. In this work, the formulas for High Cycle Fatigue (HCF) have been derived and the empirical formula for calculating stress sensitivity coefficient of a material of a random load, which facilitates fatigue calculations, has been given.
W pomiarach odporności na zmęczenie elemtnów konstrukcyjnych, które w warunkach eksploatacyjnych poddane zostały stochastycznym obciążeniom, występują widma pod postacią cykli sinusoidalnych o różnej asymetrii. Asymetria cyklu różni się współczynnikiem naprężenia definiowanym jako R = Smin/Smax. W przypadku podanego obciążenia, współczynnik R jest zmienny w zakresie -∞ do +∞. W artykule przedstawiono analizę wrażliwości naprężenia materiału na asymetrię cyklu wybranych obciążeń. Wrażliwość ta jest opisana odpowiednim współczynnikiem. W odniesieniach podano analityczne formy obliczania siły zmęczenia. W artykule powołano się na formułę HCF oraz empiryczną formułę współczynnika wrażliwości naprężenia dla materiałów poddanych wybranym obciążeniom.
Źródło:
Problemy Eksploatacji; 2010, 4; 7-17
1232-9312
Pojawia się w:
Problemy Eksploatacji
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A New Thermally-stable Insensitive High Explosive:N,N′-Bis(1,2,3,4-tetrazol-5-yl)-4,4′-diamino-2,2′,3,3′,5,5′,6,6′-octanitroazobenzene (BTeDAONAB)
Autorzy:
Mousavi, S.
Esmaeilpour, K.
Keshavarz, M. H.
Powiązania:
https://bibliotekanauki.pl/articles/951499.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
synthesis
BTeDAONAB
sensitivity
thermal stability
high explosive
Opis:
A novel high performance explosive compound, N,N′-bis(1,2,3,4-tetrazol5-yl)-4,4′-diamino-2,2′,3,3′,5,5′,6,6′-octanitroazobenzene( BTeDAONAB), is introduced which is a thermally stable, insensitive high explosive. The presence of −NH2, −N=N− groups and the tetrazole ring simultaneously in the BTeDAONAB unit surprisingly increases its thermal stability. For the identification and characterization of BTeDAONAB, different analytical techniques have been used, including melting point, IR, 1H NMR, 13C NMR spectroscopy, elemental analysis, differential thermal analysis (DTA), thermogravimetry (TG), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The sensitivity and detonation properties of BTeDAONAB were compared with 2,4,6-triamino1,3,5-trinitrobenzene (TATB) and N,N′-bis(1,2,4-triazol-3-yl-)-4,4′-diamino2,2′,3,3′,5,5′,6,6′-octanitroazobenzene (BTDAONAB), two well-known, thermally stable, insensitive high explosives, as well as hexanitrostilbene (HNS). These studies show that BTeDAONAB has favorable thermal stability with high performance.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 4; 455-465
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Insensitive HMX (Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) Nanocrystals Fabricated by High-Yield, Low-Cost Mechanical Milling
Autorzy:
Wang, Y.
Jiang, W.
Song, X.
Deng, G.
Li, F.
Powiązania:
https://bibliotekanauki.pl/articles/358912.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
nanoexplosives
HMX
thermal decomposition
sensitivity
Opis:
A mechanical approach had been adopted for fabricating HMX nanoparticles. This fabrication method avoided the recrystallization process and was different from the traditional methods employed to prepare nanoexplosives. In particular, the high yield and low cost increased the possibility of its industrial application. Specifcally, HMX particles, that had a mean size of 0.27 μm, were prepared by mechanical milling; a signifcant proportion of nano-HMX (<100 nm) were present and these were observed by TEM and SEM images. The thermal decomposition of HMX samples before and after pulverization was investigated by TG/DSC analysis. The results indicated that there was no obvious difference between the thermographs of raw and pulverized HMX. The HMX samples were investigated by friction, impact, and shock sensitivity tests. High safety was confrmed since pulverized HMX was far more insensitive than raw HMX; indeed the shock sensitivity of pulverized HMX was about 60 percent lower than that of raw HMX.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 2; 277-287
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quantum Chemical Study of Aminonitrocyclopentanes as Possible High Energy Density Materials (HEDMs)
Autorzy:
Bai, J.
Chi, W. J.
Li, L. L.
Yan, T.
Wen, X. E.
Li, B. T.
Wu, H. S.
Ma, F. L.
Powiązania:
https://bibliotekanauki.pl/articles/358101.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
cyclopentane derivatives
high energy density materials
impact sensitivity
quantum chemistry
DFT
available free space
Opis:
Nitro and amine groups were introduced into the cyclopentane skeleton, and the heats of formation, detonation performance, bond dissociation energies, and impact sensitivity for these aminonitrocyclopentanes were calculated in detail at the B3LYP/6-311G** level. The results show that all of the derivatives have negative heats of formation, which are influenced by the position of the substituent groups. Their stabilities were estimated and analyzed according to their bond dissociation energies and calculated characteristic H50 values. Most of the compounds were found to have a lower impact sensitivity than HMX. Furthermore, the detonation velocities and detonation pressures were predicted via the Kamlet-Jacobs equation. Of all these aminonitrocyclopentanes, E has the best detonation properties (ρ = 2.05 g/cm3, D = 9.11 m/s, P = 39.62 GPa) and can be considered as a candidate high energy density material.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 4; 467-480
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studies on FOX-7 Based Melt Cast High Explosive Formulations
Autorzy:
Mishra, V. S.
Vadali, S. R.
Garg, R. K.
Joshi, V. S.
Wasnik, R. D.
Asthana, S.
Powiązania:
https://bibliotekanauki.pl/articles/358915.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
melt cast
FOX-7
LOVEX
shock sensitivity
VOD
impulse
IMs
Opis:
The key driving force in modern explosive research is the development of low vulnerable high explosive (LOVEX) compositions for future applications in insensitive munitions (IMs). The increasing demand for LOVEX has led to exhaustive studies on low vulnerable explosives as a replacement for conventional cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX) in 2,4,6-trinitrotoluene (TNT) melt cast high explosive formulations. In the present study, 1,1-diamino-2,2dinitroethene (FOX-7) has been evaluated as a possible RDX replacement in TNT based, non-aluminized as well as aluminized, melt cast formulation. FOX-7 based melt cast formulations were characterized for their sensitivity to mechanical/shock stimuli, velocity of detonation (VOD), blast parameters and thermal decomposition behavior. These characteristics are compared with the corresponding RDX based compositions as reference standard. The studies show that with little sacrifice on performance parameters, FOX-7 based, non-aluminized and aluminized, melt cast formulations are found to be less vulnerable, compared with the corresponding RDX based formulations.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 4; 569-580
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis, Crystal Structure, and Properties of a Novel, Highly Sensitive Energetic, Coordination Compound: Iron (II) Carbohydrazide Perchlorate
Autorzy:
Liu, R.
Zhou, Z.
Qi, S.
Yang, L.
Wu, B.
Huang, H.
Zhang, T.
Powiązania:
https://bibliotekanauki.pl/articles/358343.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
iron (II) carbohydrazide perchlorate
energetic material
high
sensitivity
DFT
energy gap
Opis:
A single crystal of iron (II) carbohydrazide perchlorate [FeII (CHZ)3](ClO4)2 (FeCP), a novel, lead-free, energetic coordination compound, was synthesized and its structure determined by X-ray single crystal diffraction for the frst time. The crystal belongs to the monoclinic system P2(1)/n space group, with a = 1.0066(2) nm, b = 0.8458(2) nm, c = 2.1194(4) nm, β = 100.693(3)° and Z = 4. The central Fe(II) ion is coordinated to three bidentate carbohydrazide units through the carbonyl oxygen atom and an amino nitrogen atom, forming a six-coordinated, non-centrosymmetric complex cation. The thermal analyses by differential scanning calorimetry and thermogravimetry show that the onset temperature of thermal decomposition (152.7 °C) and the critical temperature of thermal explosion of FeCP (161.2 °C) are both much lower than those of other transition metal carbohydrazide perchlorate compounds, and also those of some other primary explosives in service. FeCP has a high enthalpy of combustion, as measured by oxygen bomb calorimetry. The impact, friction and fame sensitivity tests indicate that FeCP is extremely sensitive and hazardous. Unexpected explosions occurred even during the operational processes. In order to explore the intrinsic cause of these explosions, theoretical calculations of the orbital energies were performed based on DTF. These results reveal that the impact sensitivity is positively correlated with the energy gap between HOMO and LUMO: the smaller energy gap results in the higher impact sensitivity.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 1; 17-36
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Znaczenie pozapasmowej czułości aparatury pomiarowej przy ocenie narażenia na radiofalowe pola elektromagnetyczne w sąsiedztwie linii energetycznych wysokiego napięcia
The role of out-of-band sensitivity of measurement devices in the Assessment of out-band sensitivity of measurement in the devices in the assessment of exposure to radiofrequency electromagnetic fields near high voltage power lines
Autorzy:
Gryz, K.
Karpowicz, J.
Powiązania:
https://bibliotekanauki.pl/articles/181156.pdf
Data publikacji:
2013
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
miernictwo
pole elektromagnetyczne
ocena ekspozycji
pracownicy
środowisko
metrology
electromagnetic fields
exposure assessment
workers
environment
Opis:
W artykule zaprezentowano wyniki laboratoryjnych badań pozapasmowej czułości mierników elektromagnetycznego promieniowania radiofalowego, o pasmach pomiarowych z zakresu częstotliwości 1 kHz ÷ 38 GHz, na oddziaływanie sinusoidalnie zmiennego pola elektrycznego o częstotliwości przemysłowej 50 Hz i natężeniu z zakresu 5 ÷ 30 kV/m. Wyniki badań przeanalizowano w kontekście wymagań ochrony pracowników i ludności przed oddziaływaniem pól elektromagnetycznych oraz charakterystyki złożonych środowiskowych pól, jakie mogą występować w otoczeniu elektroenergetycznych linii przesyłowych wysokiego napięcia. Stwierdzono, że oddziaływanie pól elektrycznych 50 Hz na mierniki radiofalowego pola elektromagnetycznego może w otoczeniu linii wysokiego napięcia spowodować nieuprawnione zidentyfikowanie radiofalowych pól elektrycznych i magnetycznych o natężeniach przekraczających dopuszczalne dla narażenia ludności. W pobliżu linii elektroenergetycznych wysokiego napięcia, lub w innych miejscach narażonych na silne pola elektryczne częstotliwości przemysłowej, konieczne jest używanie tylko mierników radio falowych o ustalonej czułości na pole elektryczne 50 Hz i rozważenie jej wpływu na wyniki pomiarów, biorąc pod uwagę poziom pola elektrycznego 50 Hz w poszczególnych miejscach.
The following article presents results of laboratory studies of out-of-band sensitivity of radiofrequency electromagnetic radiation measurement devices, of measurement ranges from the 1 kHz – 38 GHz range, to the influence of sinusoidal time varying electric field of power frequency 50 Hz and strength 5 – 30 kV/m. Results of studies were analyzed in the context of requirements on the workers and general public protection against the influence of the electromagnetic fields and the characteristic of environmental complex fields, which may exist in the vicinity of high voltage electric power lines. It was found, that in the vicinity of high voltage electric power lines, the influence of 50 Hz electric fields on the radiofrequency electromagnetic field measurement devices may caused unjustified identification of radiofrequency electric and magnetic fields of the strength exceeding general public exposure limits. Near high voltage power lines, and in other place highly exposed to power frequency electric field, it is required to use only radiofrequency measurement devices of known response to 50 Hz electric field and to consider its influence on the measurement results based on the level of 50 Hz electric field in particular location.
Źródło:
Bezpieczeństwo Pracy : nauka i praktyka; 2013, 9; 5-7
0137-7043
Pojawia się w:
Bezpieczeństwo Pracy : nauka i praktyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Elevated high sensitivity C-reactive protein and uric acid levels in coronary artery ectasia
Autorzy:
Demir, Şerafettin
Karakoyun, Gulhan
Kanadasi, Mehmet
Powiązania:
https://bibliotekanauki.pl/articles/1039196.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
coronary ectasia
coronary artery disease
uric acid
high sensitive C-reactive protein
Opis:
Aim: The aim of this study is to examine uric asid (UA) and high sensitive C-Reactive protein (Hs-CRP) levels in patients with coronary artery ectasia (CAE). Materials and Methods: Ninety-eight patients with isolated CAE (mean age 57.5±10.3), (group-I), 110 patients with CAD but without CAE (mean age 56.3±10.7), (group-II), and 105 patients with normal coronary angiographies (mean age 58.1±10.8), (group-III) were included in the study. Blood samples of all individual were taken after coronary angiography from an antecubital vein, the patients uric acid and Hs-CRP levels were assessed. The severity of ectasia was evaluated and categorized according to Markis. Results: A significant difference was not seen in serum uric acid and Hs-CRP levels between CAE and CAD groups. However, relative to the control group, uric acid and Hs-CRP levels in CAE and CAD groups were higher to a significant degree (p=0.001, p<0.001, respectively), (p<0.001, p<0.001, respectively). The statistical significant was detected between subgroups type I and type IV, Hs-CRP and UA were statistically high in subgroup type I. (p=0.012, p=0.033, respectively) In multiple regression analysis, CAE and CAD were independently associated with UA (β=0.76; p<0.001, β=0.68; p<0.001, respectively) and Hs-CRP (β=0.66; p<0.01, β=0.62; p<0.01, respectively) along with diabetes mellitus (β=0.61; p=0.039, β=0.94; p=0.028, respectively). Conclusion: In conclusion, the blood uric acid and Hs-CRP values in our study have been observed to be higher in the individuals with coronary arteri ectasia in comparison to normal individuals, and the increase in these values were found to be parallel to the extent of the ectasia.
Źródło:
Acta Biochimica Polonica; 2014, 61, 4; 687-691
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of electric field control methods for foil coils in high-voltage linear actuators
Autorzy:
Beek, T. A. van
Jansen, J. W.
Lomonova, E. A.
Powiązania:
https://bibliotekanauki.pl/articles/141173.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
electric field control methods
high voltage
linear actuators sensitivity analysis
stress grading
Opis:
This paper describes multiple electric field control methods for foil coils in high-voltage coreless linear actuators and their sensitivity to misalignment. The investigated field control methods consist of resistive, refractive, capacitive and geometrical solutions for mitigating electric stress at edges and corners of foil coils. These field control methods are evaluated using 2-D boundary element and finite element methods. A comparison is presented between the field control methods and their ability to mitigate electric stress in coreless linear actuators. Furthermore, the sensitivity to misalignment of the field control methods is investigated.
Źródło:
Archives of Electrical Engineering; 2015, 64, 4; 629-640
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Predicted Crystal Structures, Analysis, Impact Sensitivities and Morphology of Solid High-Energy Complexes: Alkaline-Earth Carbohydrazide Perchlorates
Autorzy:
Liu, Y.
Zhang, R.
Feng, C.-G.
Yang, L.
Zhang, T.-L.
Powiązania:
https://bibliotekanauki.pl/articles/358890.pdf
Data publikacji:
2015
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
crystal structure
density of state
thermodynamic property
impact sensitivity
crystal morphology
Opis:
The crystal structures, density of states, energy gap, thermodynamic properties, impact sensitivities and morphology of beryllium carbohydrazide perchlorate ([Be(CHZ)3](ClO4)2), magnesium carbohydrazide perchlorate ([Mg(CHZ)3](ClO4)2), calcium carbohydrazide perchlorate ([Ca(CHZ)3] (ClO4)2), strontium carbohydrazide perchlorate ([Sr(CHZ)3](ClO4)2) and barium carbohydrazide perchlorate ([Ba(CHZ)3](ClO4)2) were investigated using the density functional theory (DFT) and crystal morphology theory. The results show that all of the complexes have six-coordinated distorted octahedra, which is different from previous works. This was rationalised by consideration of the intermolecular interactions in the crystal structures. Hence the crystal structure is now more reliable. The chemical reactions of the whole molecule may be triggered by an electron transition of CHZ or ClO4 −. Furthermore the energy gaps were observed, and the values of the impact sensitivities were inferred to have the following sequence: [Be(CHZ)3](ClO4)2 > [Mg(CHZ)3](ClO4)2 > [Sr(CHZ)3](ClO4)2 > [Ca(CHZ)3](ClO4)2 > [Ba(CHZ)3](ClO4)2. In addition, the thermodynamic equations at 25-1000 K were obtained. The positive values of the standard molar free enthalpies shows that carbohydrazide perchlorates are stable at 298.15 K. The (1 0 -1) and (0 0 2) faces are the most important growth directions of the crystal morphologies, and have the minimum growth rates. From the cleaved main growth faces, it can be deduced that surface active agents with active hydrogen atoms in the functional groups could be used as crystal-control reagents to control the crystal morphology for alkaline-earth carbohydrazide perchlorates.
Źródło:
Central European Journal of Energetic Materials; 2015, 12, 2; 229-248
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
High order sensitivity analysis of a mistuned blisk including intentional mistuning
Autorzy:
Pohle, L.
Tatzko, S.
Panning-von Scheidt, L.
Wallaschek, J.
Powiązania:
https://bibliotekanauki.pl/articles/281842.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
turbine blades
mistuning
sensitivity analysis
Opis:
Small deviations between turbine blades exist due to manufacturing tolerances or material inhomogeneities. This effect is called mistuning and usually causes increased vibration amplitudes and also a lower service life expectancy of bladed disks or so called blisks (bladed integrated disk). The major resulting problem is to estimate the maximum amplitude with respect to these deviations. Due to the probability distribution of these deviations, statistical methods are used to predict the maximum amplitude. State of the art is the Monte-Carlo simulation which is based on a high number of randomly re-arranged input parameters. The aim of this paper is to introduce a useful method to calculate the probability distribution of the maximum amplitude of a mistuned blisk with respect to the random input parameters. First, the applied reduction method is presented to initiate the sensitivity analysis. This reduction method enables the calculation of the frequency response function (FRF) of a Finite Element Model (FEM) in a reasonable calculation time. Based on the Taylor series approximation, the sensitivity of the vibration amplitude depending on normally distributed input parameters is calculated and therewith, it is possible to estimate the maximum amplitude. Calculating only a single frequency response function shows a good agreement with the results of over 1000 Monte-Carlo simulations.
Źródło:
Journal of Theoretical and Applied Mechanics; 2017, 55, 1; 353-368
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improving sensitivity of residual current transformers to high frequency earth fault currents
Autorzy:
Czapp, S.
Dobrzyński, K.
Klucznik, J.
Lubosny, Z.
Kowalak, R.
Powiązania:
https://bibliotekanauki.pl/articles/141169.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
current transformers
earth fault currents
electric devices
electromagnetic couplings
high frequency
Opis:
For protection against electric shock in low voltage systems residual current devices are commonly used. However, their proper operation can be interfered when high frequency earth fault current occurs. Serious hazard of electrocution exists then. In order to detect such a current, it is necessary to modify parameters of residual current devices, especially the operating point of their current transformer. The authors proposed the modification in the structure of residual current devices. This modification improves sensitivity of residual current devices when high frequency earth fault current occurs. The test of the modified residual current device proved that the authors’ proposition is appropriate.
Źródło:
Archives of Electrical Engineering; 2017, 66, 3; 485-494
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microarray-core based circular photonic crystal fiber for high chemical sensing capacity with low confinement loss
Autorzy:
Asaduzzaman, S.
Ahmed, K.
Powiązania:
https://bibliotekanauki.pl/articles/174575.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
circular photonic crystal fiber
confinement loss
elliptical core
chemical sensor
relative sensitivity
Opis:
In this article, a circular photonic crystal fiber based chemical sensor has been presented where core region is designed with an array of elliptical holes. The proposed structure is numerically investigated by using a full vectorial finite element method. From the numerical results, it is observed that introducing an array of elliptical holes helps to obtain the high relative sensitivity and realizes a low confinement loss. In addition, the increase in the value of the diameter of holes in the innermost ring enhances the relative sensitivity. Moreover, the increase in the value of the diameter of holes in the outermost ring reduces the confinement loss. In this work, we have considered an industrially valuable chemical ethanol. Simulation results disclose that the highest relative sensitivity of proposed photonic crystal fiber is 29.25% for ethanol and the confinement loss is 7.68 × 10–7 dB/m at the wavelength 1.5 µm.
Źródło:
Optica Applicata; 2017, 47, 1; 41-49
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Different Ignition Responses of Powdery and Bulky 1,3,5-Triamino-2,4,6-trinitrobenzene (TATB) Based Polymer-bonded Explosives under Ultra-high Voltage Electrostatic Discharge
Autorzy:
Lyu, Z.
Long, X.
Li, Z.
Dai, X.
Deng, C.
He, S.
Li, M.
Yao, K.
Wen, Y.
Powiązania:
https://bibliotekanauki.pl/articles/358240.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
electrostatic spark sensitivity
ultra-high voltage electrostatic discharge
thermal effect
electric field effect
Opis:
The electric spark induced ignition mechanism for explosives needs further study. The ignition of powdery and bulky TATB by electrostatic discharge (ESD) was investigated. Up to 200 kV ultra-high voltage ESD was applied to powdery and bulky explosives of two TATB-based polymer-bonded explosives (named PBX-1 and PBX-2). The results showed that the spark sensitivities of powdery and bulky explosives are extremely different for the same formulation. The 50% ignition voltages of powdery PBX-1 and PBX-2 were 10.8 kV and 8.5 kV, respectively, while the values for the bulky samples (tablets) were not less than 200 kV. Both heat and the electric field can be transmitted into the powdery samples, on the other hand only the electric field can be transmitted into the bulk samples. The electric field has a smaller contribution while the heat has a larger contribution to the ignition during an ESD, i.e., the thermal effect plays a main role in the ignition process. Our experimental results are in good agreement with recent results calculated by density functional theory.
Źródło:
Central European Journal of Energetic Materials; 2018, 15, 2; 283-298
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 20

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