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EN
In this study, the effect of sugar palm nanocrystalline cellulose (SPNCC) loading (0.00–0.10 wt %) on the electrical resistance, resistivity, and conductivity of SPS/SPNCC (SPS – sugar palm starch) nanocomposite films were evaluated. The experiments were conducted using the four-probe method and Ohm’s law, resistivity and conductivity equations were utilized to obtain the electrical properties. The results revealed that the resistivity values of SPS/SPNCC films were found to be in the range of 3.1 · 102 to 1.5 · 104 (Ω · cm).
PL
Oceniono wpływ dodatku nanokrystalicznej celulozy otrzymanej z palmy cukrowej (SPNCC) (0,00–0,10% mas.) na rezystancję elektryczną, rezystywność i przewodnictwo folii wytworzonych z nanokompozytów (SPS/SPNCC) na bazie skrobi z palmy cukrowej (SPS). Badania przeprowadzono metodą czterosondową z zastosowaniem prawa Ohma; właściwości elektryczne określono na podstawie równań rezystywności i przewodności. Stwierdzono, że wartość rezystywności folii SPS/SPNCC mieści się w zakresie konduktywności od 3,1 · 102 do 1,5 · 104 (Ω · cm).
EN
True formation resistivity Rt measurement is one of the fundamental logs in the calculation of hydrocarbon resources. That is why it is very important to have the most reliable resistivity data possible. In this paper, the various outcomes obtained by Polish well log analysts and engineers for the proper determination of hydrocarbon saturation in the Main Dolomite deposits in the Polish Lowland are presented. The long history of efforts directed to make proper exploitation decisions in wells where the Groningen effect has been observed is illustrated, starting with the standard measurement and interpretational approach, through the modified construction of a reference electrode in a Laterolog device and ending with an examination of HRLA (High Resolution Laterolog Array) or Array Compensated Resistivity Tool) ACRt results. The processing of resistivity logs with the special Poprawki software is included.
EN
This research aimed to discover the possible efects of 1D assumption violations on VES data interpretations. In order to do so, 1D inversion results of logarithmically spaced and linearly spaced VES measurements are compared with their relevant 2D inverted models. Some real case studies are also examined by 1D and 2D inversions to test the results. It is found that linearly spaced VES measurements are not really suitable for 1D inversion in the case of 1D assumption violations and logarithmically spaced VES can better handle these problematic features. In the case of semi-infnite horizontal layers and also small surface resistivity inhomogeneities, logarithmically spaced VES datasets mostly provide a reliable 1.5D model while linearly spaced VES datasets sufer from remarkable artifacts. In the case of vertical structures, both linearly spaced and logarithmically spaced VES techniques fail. In this case (i.e., a vertical dike), artifacts in the form of “extra layer” appear in those VES stations that are adjacent to the dike. However, for VES stations on the dike structure, no extra layer appears in the 1D inversion result. It must be emphasized that 1D violating features are not improbable in many geological situations so they must be considered in mind when processing and interpreting the geophysical VES data.
EN
A revision of the standard approach to characterization of thin-semiconductor-layer Hall samples has been proposed. Our results show that simple checking of I(V) curve linearity at room temperature might be insufficient for correct determination of bias conditions of a sample before measurements of Hall effect. It is caused by the nonlinear behaviour of electrical contact layers, which should be treated together with the tested layer a priori as a metal-semiconductor-metal (MSM) structure. Our approach was examined with a Be-doped p-type InAs epitaxial layer, with four gold contacts. Despite using full high-quality photolithography a significant asymmetry in maximum differential resistance (Rd) values and positions relative to zero voltage (or current) value was observed for different contacts. This suggests that such characterization should be performed before each high-precision magneto-transport measurement in order to optimize the bias conditions.
5
EN
This paper tried to prove the capability of a geophysical method, called VLF (very low frequency) for peat thickness variability exploration. The method involved using the VLF receiver to measure the VLF properties emitted by the ground from the study area. The study was carried out in Jambi Province of Indonesia in three different depths of peat area, i.e.; very deep (8–15 m), deep (3–8 m) and shallow (0–3 m) peat. The depth was confirmed by direct measurement. The VLF measurement was done along transects on each areas. The data was processed using NAMEMD (Noise Assisted Multivariate Empirical Mode Decomposition) method and converted into value and depth of resistivity using Inv2DVLF software. The study indicated that the resistivity, shows significant difference (F(2,6317) = 4.525, p = 0.011) between the area of very deep peat and the shallow peat. The resistivity varies according to peat thickness. In the very deep area, it tends to be statistically similar until 7.32 meter depth and starts to differ significantly at the depth of 11.46 meters. In turn, in the area of deep peat, it is statistically similar until 4.72 meter and starts to show differences at 7.32 m depth. However, in shallow area, it does not exhibit the differences as in the area of deep peat. This proved that the VLF method works properly in deep and very deep peat and is capable of indicating the peat thickness.
6
Content available Rezystywność staliwa aluminiowego
PL
W pracy przedstawiono wyniki badań dwóch gatun-ków staliwa (oznaczonych dalej jako Stop 1 oraz Stop 2). Stop 1 zawiera między innymi: 0,25% C, 11,5% Al, 5,85% Cr, 1,97% Mo. W przypadku Stopu 2 zawartość węgla wynosiła 0,035%, natomiast aluminium 13,5%, pierwiastki takie, jak: Cr, Ni, Sb, B, nie przekroczyły 1% udziału w składzie chemicznym tego stopu. Badania rezystywności Stopu 1 przeprowadzono podczas badania odporności na zmęczenie cieplne, natomiast Stop 2 badano na przygotowanym stanowisku, realizując pomiar rezystancji metodą czteropunktową.Dla Stopu 1 przeprowadzono pomiary rezystancji w funkcji czasu, wydłużenia oraz temperatury. Dla porównania przedstawiono wyniki badań innych stopów badanych na tym stanowisku w ramach realizacji innych prac B+R.Korzystając z materiału uzyskanego podczas badania lejności Stopu 2, określono wpływ warunków krzepnięcia na rezystywność. Przedstawiono wyniki badań kalorymetrycznych tego stopu, określając temperaturę przemian fazowych dla różnych warunków krzepnięcia Stopu 2.
EN
The paper presents the results of investigations of two cast steel grades (further referred to as Alloy 1 and Al-loy 2). Alloy 1 contains, among others, 0.25% C, 11.5% Al, 5.85% Cr, 1.97% Mo, in Alloy 2 was obtained 0.035% C, 13.5% Al, elements such as Cr, Ni , Sb, B, did not exceed 1% share in the chemical composition of this alloy. Resistivity tests of Alloy 1 were carried out during the test of resistance to thermal fatigue, while Alloy 2 was tested on a prepared test stand and the resistance was measured using a four-point method.For Alloy 1, the resistance was measured as a function of time, elongation and temperature. For comparison, the results of tests of other alloys conducted on this stand within the framework of other R&D works are presented.Using the material obtained during the test for castability of Alloy 2, the influence of solidification conditions on resistivity was determined. The results of calorimetric tests of this alloy are presented, determining the phase transition temperature for various solidification conditions of Alloy 2.
PL
W niniejszej pracy przedstawiono wyniki badań wpływu rodzaju podłoża na właściwości cienkich warstw ITO, takich jak chropowatość powierzchni, zwilżalność, rezystywność oraz współczynnik odbicia światła. Analizie poddano warstwy ITO o grubości 70 nm, naniesione metodą rozpylania magnetronowego na podłoża z krzemionki amorficznej (SiO₂), krzemu (Si), poliwęglanu (PC) oraz poli(tereftalanu etylenu) (PET). Badania wykazały istotny wpływ ukształtowania powierzchni podłoża na właściwości naniesionej cienkiej warstwy ITO. Uzyskana rezystywność warstw ITO wykazała różnice nawet o kilka rzędów wielkości dla zastosowanych różnych podłoży. Cienkie warstwy ITO wykazały właściwości hydrofilowe na każdym badanym podłożu, natomiast największą wartością kąta zwilżania charakteryzowała się warstwa ITO/SiO₂. Najmniejszą wartość współczynnika odbicia światła dla długości fali 550 nm wykazała warstwa tlenku indowo-cynowego na podłożu krzemowym i wynosiła ok. 3,2%.
EN
This paper presents the results of research on the influence of substrate type on the properties of ITO thin films, such as surface roughness, wettability, resistivity and light reflectance. ITO 70 nm thick coatings were deposited using magnetron sputtering to amorphous silica (SiO₂), silicon (Si), polycarbonate (PC) and polyethylene terephthalate (PET) substrates. The research showed a significant influence of the surface roughness of the substrate on the properties of the deposited ITO thin film. The obtained resistivity of ITO thin films varied even by several orders of magnitude for the various substrates used. Investigated materials showed a hydrophilic properties on each substrate, but the ITO/SiO₂ layer was characterized by the highest value of the contact angle. The lowest value of the reflectance at the wavelength of 550 nm showed the indium-tin oxide thin film deposited on the silicon substrate and was about 3.2%.
EN
Marconite is often used as alternative material to improve the performance of earth grounding system. This study aims to investigate of the physical and mechanical behaviour of conductive aggregate derived from Marconite namely, the electrical resistivity, water absorption, and crushing strength. In addition, similar tests were also conducted on mortar aggregate for comparison. The resistivity of aggregates were measured using soil box method. Test results showed that the electrical resistivity, water absorption, and crushing strength of both aggregates varied with time. These values were found to be stabilised after approximately after 14 days. The electrical resistivity for aggregates containing Marconite were found to be 39.2 Ω.m, far lower than 12700 Ω.m obtained for mortar-based aggregates. Similarly, the water absorption for Marconite aggregates were greater compared to mortar aggregates. On the other hand, the crushing strength for Marconite aggregates was to be lower. Incorporating Marconite significantly improved the electrical resistivity behaviour while maintaining acceptable mechanical properties crucial for electrical grounding purposes.
EN
Effectiveness of transient electromagnetic method (TEM) used for the localization of Pb–Zn ore bodies at the Cho Don deposit, province Bac Can, North Vietnam is appraised based on the modelling processes results. Conductive Pb–Zn ore bodies hosted in high-resistive limestone are in good conditions for the application of the TEM. The modelling process relays on the calculation of the voltage decay in time domain formed from the induced magnetic field diffusing into the study medium, when a pulse current with a given frequency is flowing in a transmitting loop coil. The model results show that the power current of 1 A transmitted from the coils with 100 or 400 m of size is effective for localization of the Zn–Pb ore bodies. However, the resolution and penetration depth of the TEM with a coil of L = 100 m is better and shorter in comparison with those in the case using the coil L = 400 m.
EN
For the induction heating process, the knowledge of the material parameters of the charge is great importance both at the stage of the design and its operation. Study is presenting the sensitivity analysis of electrical parameters of induction heating setup and dedicated magnetic flux probe on electrical parameters of induction heated charge. These dependencies can potentially be used to estimate the value of material parameters, as long as the sensitivity tested is sufficiently large and unambiguous. Results of conducted examinations allows to implement proposed method on real laboratory stand.
PL
Przy nagrzewaniu indukcyjnym znajomość parametrów materiałowych wsadu ma istotne znaczenie zarówno na etapie projektowania stanowiska, jak i jego eksploatacji. W pracy przedstawiono analizę wrażliwości łatwo mierzalnych parametrów elektrycznych nagrzewnicy indukcyjnej oraz dedykowanego czujnika strumienia magnetycznego, na zmianę elektrycznych parametrów materiałowych nagrzewanego wsadu. Tego typu zależności mogą być potencjalnie wykorzystywane do szacowania wartości parametrów materiałowych, o ile badana wrażliwość jest dostatecznie duża i jednoznaczna. Osiągnięte rezultaty pozwalają podjąć próbę wykorzystania zaproponowanej metody na rzeczywistym stanowisku badawczym.
EN
Heavily In doped zinc oxide (IZO) thin films were deposited on glass substrates by dip-coating method with different concentrations of indium. The effect of heavy In doping on the structural, morphological, optical and electrical properties of ZnO was discussed on the basis of XRD, AFM, UV-Vis spectra and Hall effect measurements. The diffraction patterns of all deposited films were indexed to the ZnO wurtzite structure. However, high In doping damaged the films crystallinity. The highest optical transmittance observed in the visible region (>93 %) exceeded that of ITO: the absolute rival of the most commercial TCOs. The grain size significantly decreased from 140 nm for undoped ZnO to 17.1 nm for IZO with the greatest In ratio. The roughness decreased with increasing In atomic ratio, indicating an improvement in the surface quality. Among all synthesized films, the sample obtained with 11 at.% indium showed the best TCO properties: the highest transmittance (93.5 %) and the lowest resistivity (0.41 Wcm) with a carrier concentration of 2.4 × 1017 cm-3. These results could be a promising solution for possible photonic and optoelectronic applications.
PL
Parametry materiałowe, w tym parametry elektryczne mają fundamentalne znaczenie dla przebiegu procesu nagrzewania indukcyjnego. W opracowaniu sprawdzono wrażliwość łatwo mierzalnych parametrów elektrycznych nagrzewnicy indukcyjnej oraz sygnału napięciowego czujnika strumienia magnetycznego wzbudnika na elektryczne parametry materiałowe wsadu. Osiągnięte wyniki symulacyjne pozwalają stwierdzić, że zaproponowana metoda pomiaru strumienia magnetycznego rokuje na możliwość zastosowania do technicznego określania elektrycznych parametrów materiałowych wsadu.
EN
The study was devoted to sensitivity analysis of methods for estimating electrical parameters of induction heated charge. Analysis were made using dedicated software for electromagnetic and thermal calculations. Influence of electrical parameters of charge on electrical parameters of induction setup were made. Achieved results for change of basic electrical parameters of induction setup were not satisfying, but measuring change of magnetic flux with dedicated coil allows to achieve promising results for further application in real, dedicated laboratory stand.
13
EN
This paper focuses on the techniques and results of electrical research into complex terrigenous and carbonate reservoirs. Presented here, are the electric data and their relation to the capacity properties of Cambrian sandstones, limestones and dolomites originating from the Volodymyrska area in Volyno-Podillia (Ukraine). Their petroelectrical models are generated.
PL
Artykuł skupia się na technikach i wynikach badań elektrycznych w złożonych zbiornikach terygenicznych i węglanowych. Prezentowane są tu dane elektryczne i ich związek z właściwościami pojemności kambryjskich piaskowców, wapieni i dolomitów pochodzących z obszaru Volodymyrska na Vołyno-Podolu (Ukraina). Ich petroelektryczne modele są generowane.
14
Content available remote Synthesis and characterization of indium tin oxide nanoparticles via reflux method
EN
Synthesis of indium tin oxide (ITO) nanoparticles by reflux method without chlorine contamination at different pHs, temperatures, solvents and concentrations has been studied. Indium chloride, tin chloride, water, ethanol and Triton X-100 were used as starting materials. Structure, size, surface morphology and transparency of indium tin oxide nanoparticles were studied by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and UV-Vis spectrophotometry. XRD patterns showed that 400 °C is the lowest temperature for synthesis of ITO nanoparticles because metal hydroxide does not transform to metal oxide in lower temperature. FT-IR results showed the transformation of hydroxyl groups to oxide. SEM images showed that pH is the most important factor affecting the nanoparticles size. The smallest nanoparticles (40 nm) were obtained at pH = 8.8. The size of crystallites was decreased by lowering of concentration (0.025 M).
EN
Lead sulphide (PbS) and zinc- doped lead sulphide (Zn–PbS) thin films were prepared by chemical spray pyrolysis on soda lime glass substrates at a temperature of 250 °C. Precursors were prepared from chemical reagents including zinc acetate, lead acetate and thiourea. The deposited films thicknesses and elemental composition were studied by Rutherford backscattering spectroscopy (RBS); the percentages of Pb and S were estimated as 40.58 % and 59.42 %, respectively, while for the Zn-doped sample, the percentages of Zn, Pb and S were respectively 4.84 %, 44.57 % and 50.59 %. Morphological studies revealed that the films were continuous and the particles were uniformly distributed across the substrate surface. AFM probe revealed nanostructured films with particles densely distributed across the substrates surfaces with incorporation of Zn2+. Statistical distribution of the grains over a specific projected area indicated average growth height of about 47 nm. Optical studies indicated that the transmission in visible light region of Zn-PbS thin film was superior to that of the undoped sample. Interband transition of both PbS and Zn-PbS films is directly allowed and their energy band gaps were found to be 0.43 eV and 1.45 eV, respectively. Electrical characterization showed that both films are of p-type conductivity with surface resistivity values of the order of 104Ω·cm.
16
PL
Przedstawiono ocenę efektywności elektrotermicznej regeneracji dwóch typów węgli aktywnych Sorbonorit 4 (S4) i Sorbonorit B4 (SB4) stosowanych do usuwania par propan 2-olu z powietrza. Stwierdzono, że węgiel SB4 miał wyższą rezystywność od S4, co wpłynęło na sprawność procesu elektrotermicznego. Zwiększenie temperatury i napięcia elektrycznego spowodowało wzrost efektywności odzyskiwania par alkoholu. Zapotrzebowanie energii do procesu desorpcji było 5÷6 razy większe niż wartość izosterycznego ciepła adsorpcji.
EN
The electrothermal regeneration efficiency of two types of activated carbons Sorbonorit 4 (S4) and Sorbonorit B4 (SB4) was evaluated. They were used in the removal of propan-2-ol (IPA) vapour from air. It was found that the SB4 carbon had the higher resistivity than S4 which affected the electrothermal process efficiency. The increase in temperature and electrical voltage affected the increase in the recovery efficiency of alcohol vapour. The energy consumption in the desorption process was 5-6 times greater than the adsorption isosteric heat.
EN
This paper presents calculation of the electron-impurity scattering coefficient of Bloch waves for one dimensional Dirac comb potential. The impurity is also modeled as delta function pseudopotential that allows explicit solution of the Schrodinger equation and scattering problem for Bloch waves.
18
Content available remote Laminat z włókna węglowego jako sensor tekstylny – badania zmian oporności
PL
Umiejętność autodetekcji zagrożeń i ostrzegania użytkownika jest jedną z najbardziej pożądanych cech współczesnego budynku. Kompozyty zbrojone włóknami wysokiej wytrzymałości znajdują coraz powszechniejsze zastosowanie w budownictwie, zwłaszcza we wzmacnianiu konstrukcji, gdzie wymagane są możliwie najlepsze cechy mechaniczne. Autorzy artykułu opracowali inteligentną tkaninę, której włókna węglowe stanowią nie tylko zbrojenie, ale również sensor odkształceń. Jej idea opiera się na budowie tensometru, w którym włókna węglowe pełnią rolę przewodnika, natomiast włókna szklane lub akrylowe rolę osnowy i izolatora. Przeprowadzono wstępne testy laboratoryjne, których celem było opracowanie efektywnych technik pomiaru oraz ocena skuteczności wzmocnienia wybranych konstrukcji budowlanych, głównie zginanych belek żelbetowych i drewnianych. Przedstawione w artykule wyniki badań są bardzo obiecujące, chociaż dalszego dopracowania wymaga technologia produkcji tkaniny.
EN
The ability to auto-detection of threats and user warnings is one of the most desirable features of a modern building. At the same time composites reinforced with highstrength fibers are increasingly widespread use in construction, especially in strengthening the structures, where the best possible mechanical properties are required. The authors of the paper have developed an intelligent fabric, wherein the carbon fibers are not only reinforcement but also the deformation sensor. The idea is based on the construction of the strain gauge, wherein the carbon fibers serve as a electrical conductor, and glass fibers or acrylic matrix has the role of insulator. Preliminary laboratory tests aimed at creating effective measure techniques and assess the effectiveness of the strengthening of selected building structures, as reinforced concrete and timber beams. Presented in the paper results of these studies are very promising, although require further advancement of the production technology.
19
Content available remote Study of high-strength and high-conductivity Cu-Sn-Fe alloys
EN
Cu-Sn-Fe alloys with different compositions were developed by casting, normalizing treatment, cold roll and subsequent annealing treatment. The results showed that the tensile strength and resistivity of the Cu-xSn-xFe alloys (where x represents wt.%) improved with increasing the content of Sn and Fe. Compared with the as-cast alloys, the resistivity and tensile strength of the Cu-xSn-xFe alloys after normalizing and cold rolling treatment increased. In addition, the resistivity and mechanical properties of the alloys after the annealing treatment were improved significantly. Finally, a conclusion could be drawn that the annealed Cu-2Sn-5Fe alloy had good mechanical properties and resistivity, and the values of the tensile strength, mechanical elongation and resistivity reached 552 MPa, 32 % and 1.92 μΩ cm, respectively.
EN
TlBr single crystals grown using the vertical Bridgman-Stockbarger method were characterized for semiconductor based radiation detector applications. It has been shown that the vertical Bridgman-Stockbarger method is effective to grow high-quality single crystalline ingots of TlBr. The TlBr single crystalline sample, which was located 6 cm from the tip of the ingot, exhibited lower impurity concentration, higher crystalline quality, high enough bandgap (>2.7 eV), and higher resistivity (2.5 × 1011 Ω·cm) which enables using the fabricated samples from the middle part of the TlBr ingot for fabricating high performance semiconductor radiation detectors.
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