Electrical Resistivity Values Research Articles

On the origins of lubricity and surface cleanliness in ethanol-diesel fuel blends

Ethanol is the most used bio-derived fuel additive. However, adding ethanol in diesel fuel may negatively impact lubricity or surface cleanliness, which is critical for high-pressure fuel injection systems employed in compression ignition engines. This work investigates surfaces lubricated by ethanol–diesel blends. Adding 5 wt% ethanol in diesel showed negligible changes in fuel lubricity, while blending 10, 20, and 40 wt% ethanol increased wear rates by 46, 81, and 239% respectively. These increases in wear rates (with increases in ethanol by wt%) correlate with the evolution of electrical contact resistance (ECR) values over time. As more ethanol was added, the ECR values signaled thinner fuel films, more metal-to-metal contacts, and a delayed onset of frictional product growth. Raman spectra showed that forming frictional species produced by tribochemical reactions enhanced fuel lubricity. The absence of some frictional species in ethanol lubricated surfaces points to simultaneously improved surface cleanliness and reduced lubricity.

Permeability evaluation for artificial single rock fracture according to geometric aperture variation using electrical resistivity

A convenient approach was proposed by which to evaluate and monitor the permeability of a rock fracture by verifying the quantitative correlation between the electrical resistivity and permeability at laboratory scale. For this purpose, an electrical resistivity measurement system was applied to the laboratory experiments using artificial cells with the shape of a single rock fracture. Sixty experiments were conducted using rock fractures according to the geometry, aperture sizes, wavelengths, and roughness amplitudes. The overall negative relationship between the normalized electrical resistivity values and the aperture sizes directly linked with the permeability, was well fitted by the power-law function with a large determination coefficient (≈0.86). The effects of wavelength and roughness amplitude of the rock fracture on the electrical resistivity were also analyzed. Results showed that the electrical resistivity was slightly increased with decreasing wavelength and increasing roughness amplitude. An empirical model for evaluating the permeability of a rock fracture was proposed based on the experimental data. In the field, if the electrical resistivity of pore groundwater could be measured in advance, this empirical model could be applied effectively for simple, quick monitoring of the fracture permeability. Although uncertainty may be associated with the permeability estimation due to the limited control parameters considered in this research, this electrical resistivity approach could be helpful to monitor the rock permeability in deep underground facilities such as those used for radioactive waste repositories or forms of energy storage. • The electrical resistivity values were slightly increased with decreasing wavelength and increasing amplitude. • The electrical resistivity was most sensitive to the change of aperture size. • The relationship between the electrical resistivity and the aperture size directly is linked with the permeability. • The electrical resistivity method could be used as a long-term monitoring system for evaluating the hydraulic stability.

Development of Accommodation System for Faults in Thrusters of Underwater Robots

The article discusses a solution to the problem of increasing the reliability of operation of underwater robots through the use of accommodation systems that compensate for the consequences of faults that appear in the thrusters. The following types of faults were considered: 1) a fault in the rotation speed sensor of thruster, causing error in its readings; 2) overheating of the motor or short-circuiting of several turns of the winding of its armature circuit, causing a change in the value of electrical resistance; 3) the appearance of an unknown external torque effect on the engine shaft, including when winding plants on the propeller. A new method for constructing accommodation systems is proposed, which contains three stages. At the first, the detection of emerging faults is carried out using the bank of diagnostic observers. Each observer is synthesized according to a special procedure in such a way that the residual formed by it is sensitive to the appearance of various combinations of possible faults. This allows to detect each specific fault. At the second stage, the values of sensor errors and deviations of the parameters of the thruster from their nominal values are estimated by additional variable structure observers. At the third stage, additional control signals for robot’s thrusters are formed. They ensure the stabilization of dynamic properties and quality indicators of thrusters in the event of faults. The results of mathematical modeling are presented, which have confirmed the operability and high efficiency of the synthesized accommodation system.

Compound mixtures based on hydrolyzed Polyacrylonitrilereducing soil electrical resisctivity

THE PURPOSE. The purpose of the article is to define the reasons to improve the system of grounding devices design. Author studies technical decisions that reduce grounding resistance values. Results are given researches how a mineral conductive mixture, that normalizes grounding, influences a seasonal coefficient. Analysed the results of the experimental surveys. Аlso evaluates a test grounding devise’s resistance decrease compared to the resistance decrease of a control grounding device. METHODS. While solving the above problem, a number of field experiments were carried out to measure the resistance values of experimental circuit grounding devices after their near-electrode soil space had been treated with the mixture that improves the resistance of a grounding wire. RESULTS. The composition of the mixture that normalizes (reduces) soil electrical resistivity has been developed, it has contained hydro-stabilizing and lowdispersed conducting additives. There has been proposed the analytical expressions to evaluate equivalent soil electrical resistivity values after aporton of soil had been submitted by the mineral conducting mixture. CONCLUSION. The use of the mixtures based on hydrolyzed polyacrylonitrile is most effective together with the grounding wires buried in soil no deeper than the soil freezing depth that is located in the soil layers with maximum seasonal fluctuations, and will increase with the increase of the contact area of such grounding wires with the soil treated with hydrolyzed polyacrylonitrile. Additional decrease of a seasonal coefficient for the vertical compound grounding wires apparently is due to the mixture influencing their parts mounded near the ground surface. The use of complex mixtures containing both hydro-stabilizing additives and low-dispersed conducting substances allows up to three times decrease of the resistance values of a grounding device compared to a control grounding device, it allows to even seasonal fluctuation of resistance of a grounding device, and to decrease mounting capital investment for a grounding device by means of the decrease of the number of the electrodes and the territory on which they are located.

Characterization of Gd doped CeO2 thin films grown by ultrasonic spray pyrolysis

Abstract Gd concentration effect on the optical, structural, surface and electrical properties of Gd doped CeO2 thin films are coated on glass substrates by spray pyrolysis technique with precursors containing cerium nitrate hexahydrate [Ce(NO3)3·6H2O] and gadalinium nitrate hexahydrate [Gd(NO3)3·6H2O] as a source material. The structural, morphologicaly and elemental characterizations of the films have been carried out using x-ray diffraction, field emission scanning electron microscopy and energy dispersive x-ray analysis, respectively. An optical energy band gap is calculated in the range 3.3–3.8 eV from UV–Vis transmittance spectra. Surface morphologies and roughness values of the films have been investigated by atomic force microscopy. Thicknesses have been determined using spectroscopic ellipsometry technique and Cauchy–Urbach model. A four-probe setup has been used to determine the electrical resistivity values. All samples showed x-ray diffraction peaks corresponding to a cubic fluorite structure. The results indicate that the deposited films have a preferential growth in the (0 0 2) direction. The observed transmittance in the visible region has been situated between 60% and 70%. Photoluminescence spectra showed an ultraviolet emission band around 365–400 nm and the visible emission peaks between 469 and 590 nm. Raman active peaks for undoped and Gd doped CeO2 films were determined at ~465 cm−1. Finally, it has been concluded that Gd doped CeO2 films have value to work on and may be promising materials for optoelectronic applications.

Exploring the High-Temperature Electrical Performance of Ca3−xLaxCo4O9 Thermoelectric Ceramics for Moderate and Low Substitution Levels

Aliovalent substitutions in Ca3Co4O9 often result in complex effects on the electrical properties and the solubility, and impact of the substituting cation also depends largely on the preparation and processing method. It is also well-known that the monoclinic symmetry of this material’s composite crystal structure allows for a significant hole transfer from the rock salt-type Ca2CoO3 buffer layers to the hexagonal CoO2 ones, increasing the concentration of holes and breaking the electron–hole symmetry from the latter layers. This work explored the relevant effects of relatively low La-for-Ca substitutions, for samples prepared and processed through a conventional ceramic route, chosen for its simplicity. The obtained results show that the actual substitution level does not exceed 0.03 (x < 0.03) in Ca3−xLaxCo4O9 samples with x = 0.01, 0.03, 0.05 and 0.07 and that further introduction of lanthanum results in simultaneous Ca3Co4O9 phase decomposition and secondary Ca3Co2O6 and (La,Ca)CoO3 phase formation. The microstructural effects promoted by this phase evolution have a moderate influence on the electronic transport. The electrical measurements and determined average oxidation state of cobalt at room temperature suggest that the present La substitutions might only have a minor effect on the concentration of charge carriers and/or their mobility. The electrical resistivity values of the Ca3−xLaxCo4O9 samples with x = 0.01, 0.03 and 0.05 were found to be ~1.3 times (or 24%) lower (considering mean values) than those measured for the pristine Ca3Co4O9 samples, while the changes in Seebeck coefficient values were only moderate. The highest power factor value calculated for Ca2.99La0.01Co4O9 (~0.28 mW/K2m at 800 °C) is among the best found in the literature for similar materials. The obtained results suggest that low rare-earth substitutions in the rock salt-type layers can be a promising pathway in designing and improving these p-type thermoelectric oxides, provided by the strong interplay between the mobility of charge carriers and their concentration, capable of breaking the electron–hole symmetry from the conductive layers.

Resistivity Technique for the Evaluation of the Integrity of Buccal and Esophageal Epithelium Mucosa for In Vitro Permeation Studies: Swine Buccal and Esophageal Mucosa Barrier Models.

Permeation assays are important for the development of topical formulations applied on buccal mucosa. Swine buccal and esophageal epithelia are usually used as barriers for these assays, while frozen epithelia have been used to optimize the experimental setup. However, there is no consensus on these methods. In transdermal studies, barrier integrity has been evaluated by measuring electrical resistance (ER) across the skin, which has been demonstrated to be a simple, fast, safe, and cost-effective method. Therefore, the aims here were to investigate whether ER might also be an effective method to evaluate buccal and esophageal epithelium mucosa integrity for in vitro permeation studies, and to establish a cut-off ER value for each epithelium mucosa model. We further investigated whether buccal epithelium could be substituted by esophageal epithelium in transbuccal permeation studies, and whether their permeability and integrity were affected by freezing at −20 °C for 3 weeks. Fresh and frozen swine buccal and esophageal epithelia were mounted in Franz diffusion cells and were then submitted to ER measurement. Permeation assays were performed using lidocaine hydrochloride as a hydrophilic drug model. ER was shown to be a reliable method for evaluating esophageal and buccal epithelia. The esophageal epithelium presented higher permeability compared to the buccal epithelium. For both epithelia, freezing and storage led to decreased electrical resistivity and increased permeability. We conclude that ER may be safely used to confirm tissue integrity when it is equal to or above 3 kΩ for fresh esophageal mucosa, but not for buccal epithelium mucosa. However, the use of esophageal epithelium in in vitro transmucosal studies could overestimate the absorption of hydrophilic drugs. In addition, fresh samples are recommended for these experiments, especially when hydrophilic drugs are involved.

Low-temperature thermoelectric transport properties of selected metals and dielectrics

Reliable and accurate estimate of experimentally measured thermal conductivity values are presented in this work for specific materials, which carries significant importance from low temeprature application perspecive. In this regard, the thermal conductivities for copper RRR≈14 and 2014 aluminum alloy are reported within the temperature ranges of 10 K to 390 K, whereas alumina and hexagonal boron nitride materials are tested within the 10 K to 300 K. Besides this, the electrical resistivity, the Seebeck coefficient, as well as the thermoelectric figure of merit of copper and 2014 aluminum are also presented over the entire temperature range of 10–390 K. All of these properties are measured simultaneously by using Quantum Design (QD) Dynacool thermal transport option, that posseses accurate temperature control with greater degree of flexibilty in handling various material specimens. The thermal conductivity of copper has shown a diverse maximum with its purity level. The electronic conductivity calculated using Wiedemann- Franz is analyzed to highlight the electronic and lattice wave contributions to the thermal conductivity. The temperature-dependent Lorenz ratios are presented for the direct estimation of thermal conductivity using available electrical resistivity values. Finally, the material-specific, temperature-dependent correlations are proposed to estimate these properties, which can be readily used to estimate temperature-dependent transport properties.

Effect of feeding corn distillers dried grains with solubles naturally contaminated with deoxynivalenol on growth performance, meat quality, intestinal permeability, and utilization of energy and nutrients in broiler chickens

The objective of this experiment was to investigate the effect of feeding corn distillers dried grains with solubles (DDGS) naturally contaminated with deoxynivalenol (DON) on growth performance, meat quality, intestinal permeability, and utilization of energy and nutrients in broiler chickens. Two trials (growth and metabolism trials) were conducted. In the growth trial, a total of four hundred 7-day-old Ross 308 broiler chicks were allotted to 1 of 5 dietary treatments with 8 replicates in a completely randomized design. The diets were formulated to contain 5 inclusion levels of 0, 5, 10, 15, or 20% DON-contaminated DDGS in diets and were fed to birds for 21 d. Results indicated that increasing inclusion levels of DON-contaminated DDGS decreased (linear, P < 0.01) BW gain and feed efficiency of broiler chickens. The relative organ weights of the liver and breast were decreased (linear and quadratic, P < 0.05) by increasing inclusion levels of DON-contaminated DDGS in diets. The transepithelial electrical resistance values as a measure of intestinal permeability were decreased (linear, P < 0.05) by increasing inclusion levels of DON-contaminated DDGS in diets. In the metabolism trial, a total of twenty four 22-day-old Ross 308 broiler chickens were allotted to 1 of 3 dietary treatments consisting of 0, 10, or 20% inclusion of DON-contaminated DDGS in diets. Each treatment had 8 replicates. Increasing inclusion levels of DON-contaminated DDGS in diets decreased (linear and quadratic, P < 0.05) MEn (AMEn and TMEn) and apparent total tract retention of nitrogen and acid-hydrolyzed ether extract in diets. In conclusion, feeding diets containing more than 10% DON-contaminated DDGS to broiler chickens has negative effects on growth performance, intestinal permeability, and utilization of energy and nutrients in diets. Therefore, it is suggested that if DDGS is contaminated with DON, inclusion level of DDGS should be limited, possibly at less than 5.0% in broiler diets.

Effect of nickel electroplating followed by a further copper electroplating on the micro-structure and mechanical properties of high modulus carbon fibers

The nickel electroplating followed by a further copper electroplating process was conducted on high modulus carbon fibers (HMCFs), and the HMCFs were oxidized in nitric acid prior to the Ni-plating process. Effect of the electroplating process on the microstructure and mechanical properties of HMCFs was investigated. Uniform nickel particles were observed on the surfaces of Ni-plated HMCFs and fiber diameter increased from 5.0 μm to 6.1 μm. With a further Cu-electroplating process, the fiber diameter continued increasing to 7.5 μm. The Ni-plating process resulted in increased surface roughness, whereas the surface RMS and Ra values dropped significantly after the Cu-plating process. Owing to the Ni-plating treatment, the relative content of carbon element on fiber surfaces decreased from 96.54 % to 36.74 %. After a further Cu-plating process, the relative content of Cu element on HMCF surfaces was as high as 54.01 %. The electroplating process resulted in decreased tensile modulus from 415.71 GPa to 407.71 GPa. By contrast, the tensile strength of electroplated HMCFs increased by 1.1 % due to the reduction of fiber defects and stress concentration. Results also showed that both the Ni-plating and Cu-plating process could lead to significant decreases in the values of electrical resistance and resistivity.

Electrical resistivity and magnetic susceptibility of substoichiometric CdO and In doped CdO films

Undoped and In doped substoichiometric CdO nanostructured films were prepared via vapor transport method. Mixed phases of hexagonal Cd and cubic CdO were obtained. No peaks related to In or indium oxides were observed in the In doped CdO pattern. Net-like assembles of nanowires were observed for undoped CdO sample whereas a regular morphology of equally shaped grains was observed for In doped CdO sample. The evaluated room temperature electrical resistivity values for undoped and In doped CdO films were 1.56 × 102 and 2.31 × 10–2 Ωcm, respectively. The temperature dependent resistivity measurements elucidated the semiconducting behavior for undoped CdO films, whereas a semiconductor–metal with a transition around 367 K was obtained for In doped CdO film. The magnetic susceptibility showed paramagnetic-antiferromagnetic transition with Neel temperatures of 266 and 308 for undoped and In doped CdO samples, respectively.

Investigations of some physical properties of ALD growth ZnO films: effect of crystal orientation on photocatalytic activity

ZnO films have great application potentials from optoelectronic devices to photocatalysis. Detailed film properties and relations between photocatalytic activities of annealed ZnO films grown on glass and corning glass substrates by Atomic Layer Deposition Technique (ALD) were reported in the current study. The structural evolutions were investigated by X-ray diffraction. Results showed that crystal orientations are strongly dependent on substrate materials. The optical band gap values of all films change between 3.26 and 3.24 eV with annealing. Lower electrical resistivity values were obtained for as-grown films. The morphological properties of the films were investigated by atomic force microscopy. In addition, the highest value of photoactivity was determined for ZnO films grown on corning glass substrate and annealed at 600 °C with a value of 53%. Relations between crystal orientations and photocatalytic activities showed that the crystal orientations, crystallite sizes, peak intensities, and dislocation density values are highly effective on photoactivities of ZnO films.

Fabrication of Eco-Friendly Graphene Nanoplatelet Electrode for Electropolishing and Its Properties

Electropolishing is one of the most widely applied metal polishing techniques for passivating and deburring metal parts. Copper is often used as cathode electrode for electropolishing due to its low electrical resistance and low flow values. However, during the electropolishing process, elution of the cathode electrode caused by the electrolyte and remaining oxygen gas also causes critical water pollution and inhibits electropolishing efficiency. Therefore, to achieve an efficient and eco-friendly electropolishing process, development of a highly corrosion resistive and conductive electrode is necessary. We developed a highly oriented graphene nanoplatelet (GNP) electrode that minimizes water pollution in the electropolishing process. We functionalized GNP by a one-step mass-productive ball-milling process and non-covalent melamine functionalization. Melamine is an effective amphiphilic molecule that enhances dispersibility and nematic liquid crystal phase transformation of GNP. The functionalization mechanism and the material interaction were confirmed by Raman spectroscopy after high-speed shear printing. After the electropolishing process by melamine-functionalized GNP electrodes, 304 stainless steel samples were noticeably polished as copper electrodes and elution of carbon was over 50 times less than was the case when using copper electrodes. This electropolishing performance of a highly oriented GNP electrode indicates that melamine-functionalized GNP has great potential for eco-friendly electropolishing applications.

A sensitive thick film as a candidate for ethanol gas sensor from Jarosite-based minerals

We report this study that aims to know thick film sensitivity to ethanol gas. The thick film was fabricated from local mineral, is Jarosite as a source of iron oxide, and mixed with zinc oxide and Mangan oxide. The semiconductor mixture powder was synthesized by the sol-gel method, whereas the film was fabricated by a screen printing method. The film sensitivity was known with a gas sensing performance analyzer. An ethanol gas was adsorbed well by a thick film with different electrical resistance values. Due to the difference in the electrical resistance value, the thick film exhibited good sensitivity performance. The highest sensitivity was achieved approximately 91.7% of 4 gas concentration level of ethanol. Besides, the morphology of the thick film was examined by SEM that showed a pyramid-like form with a little impurity around them. The pyramid-like form looks like a spinel structure with a complex spinel-type where this structure is very well utilized for gas sensor device applications. Furthermore, these characteristics of the thick film indicated an opportunity that it can be a candidate for an ethanol gas sensor device.

Case study: Estimating the occurrence of sea water intrusion using geoelectrical method in Pangandaran district

Research to find out intrusion in Pangandaran is very interesting, because this area is close to coastal objects that has been expanding and leading tourist attraction in West Java, Indonesia. This intrusion information is useful to determine aquifer locations which indicate below that the location is saturated water. If this aquifer locations are detected in large areas and wide volume, then this location will have potential liquefaction during a big earthquake. This research could be used as the first step before the next research to measure and calculate on either location by detail grid and radius with these 2 lines, so it is gotten direct and large distribution of sea-water intrusion. The purpose of this study is to identify the subsurface structures to get an overview of sea-water intrusion. The method used is geoelectrical based on the electrical resistance value of the rock type. The results of the measurement of 2 lines and data processing showed that the line in Pesona Park Pangandaran and the line in SMPN 1 Soccer Field Pangandaran showed the presence of sea-water intrusion that very salty with a resistance value of 0.5-2.0 ohm-meter, at a depth of 19-20 meters.

Использование геофизических методов для изучения криогенного состояния пород разрабатываемых золоторудных месторождений Магаданской области

The authors consider the problem of applicability and sensitivity of methods of ground geophysics for studying the state of rock massifs in the permafrost zone. Using the example of gold deposits in Magadan Oblast, they study and analize peculiarities of changes in the values of electrical resistivity and induced polarization of soils, depending on their cryogenic state. Sufficiently high efficiency of geophysical methods in distinguishing thawed, seasonally thawed, locally frozen, and permafrost rocks is substantiated. The research results are recommended for optimizing field development processes in various engineering and geological settings.

Morphological, structural, and electrical properties of PbS thin films deposited on HfO2, SiO2, and Al2O3 for TFTs applications

PbS thin films were deposited by the chemical bath deposition (CBD) technique at 43 °C on HfO2, SiO2, and Al2O3 dielectric films, which were previously deposited by atomic layer deposition (ALD) on <100> silicon wafers. The effect of the dielectric surface on the final morphology and structure of the PbS films was studied to find the most suitable dielectric/PbS system for thin film transistors (TFTs) applications. The PbS films showed a polycrystalline structure related to the galena cubic phase. The surface morphology of the PbS films was analyzed by scanning electron microscopy (SEM), which evidenced a gradual coverage of the surface of the dielectric with the deposition time. The shape of the PbS grains evidenced a strong dependence with the dielectric substrate employed. The PbS films deposited on HfO2 achieved a well-defined and compact microstructure in comparison with the other dielectric substrates. The electrical properties of the PbS films were studied by Hall effect measurements. A p-type conductivity with Hall mobility up to 0.44 cm2V−1cm−1 and electrical resistivity values between 102-105 Ωcm were obtained. Finally, two TFTs were fabricated by using standard photolithography processes, where the PbS film was used as semiconductor active layer and HfO2 (30 nm) as dielectric gate layer, respectively. The electrical response of the PbS-based TFTs evidenced a p-type behavior with a mobility in the saturation regime (μsat) in the range of 0.006–0.011 cm2/Vcm and ION/IOFF current ratio in the order of 102. The TFTs operated in depletion mode with a low positive threshold voltage (VTH) between 0.5 and 2 V.

Influências pluviométricas no mapeamento das características da paisagem de um sítio arqueológico com a aplicação de métodos geofísicos e geoestatísticos

Archaeological studies are important for understanding the historical environments and analysis of the consequences of their changes in the current period, and geophysical methods are an important tool for enabling a low-impact analysis on these. This study evaluated the influence of rainfall in mapping of landscape features of the archaeological site AP-MA-05 using geophysical and geostatistical methods. To obtain the data, the geophysical method of electroresistivity was used in an area of UNIFAP of 10 x 20 meters. The rainfall data were collected in INMET station in Macapá. Data analysis was performed with use of statistical and geostatistical methods. In rainy season, soil resistivity presented a minimum of 198.7 ohm.m and maximum values of up to 3946 ohm.m, with an average of 1188.87 ohm.m. In the less rainy season the observed values were 394 ohm.m (minimum) and 5863 ohm.m (maximum), with an averaging of 2078.31 ohm.m. This demonstrates the influence of rainfall on apparent resistivity, since the more intense the rains that occurred at the time of data were obtained, the lower the values of electrical resistivity. The best association between the research method, the survey period based on climate aspects and the application of geostatistical methods facilitated the characterization of the site as a future support for its prospection.

Aflatoxin B1 and Aflatoxin M1 Induce Compromised Intestinal Integrity through Clathrin-Mediated Endocytosis.

With the growing diversity and complexity of diet, humans are at risk of simultaneous exposure to aflatoxin B1 (AFB1) and aflatoxin M1 (AFM1), which are well-known contaminants in dairy and other agricultural products worldwide. The intestine represents the first barrier against external contaminants; however, evidence about the combined effect of AFB1 and AFM1 on intestinal integrity is lacking. In vivo, the serum biochemical parameters related to intestinal barrier function, ratio of villus height/crypt depth, and distribution pattern of claudin-1 and zonula occluden-1 were significantly affected in mice exposed to 0.3 mg/kg b.w. AFB1 and 3.0 mg/kg b.w. AFM1. In vitro results on differentiated Caco-2 cells showed that individual and combined AFB1 (0.5 and 4 μg/mL) and AFM1 (0.5 and 4 μg/mL) decreased cell viability and trans-epithelial electrical resistance values as well as increased paracellular permeability of fluorescein isothiocyanate-dextran in a dose-dependent manner. Furthermore, AFM1 aggravated AFB1-induced compromised intestinal barrier, as demonstrated by the down-regulation of tight junction proteins and their redistribution, particularly internalization. Adding the inhibitor chlorpromazine illustrated that clathrin-mediated endocytosis partially contributed to the compromised intestinal integrity. Synergistic and additive effects were the predominant interactions, suggesting that these toxins are likely to have negative effects on human health.

Comparison of Electrical Resistivity of Soots Formed by Combustion of Kerosene, Diesel, Aviation Fuel and their Mixtures

This research paper presents analysis of electrical resistivity values of soots formed by combustion of kerosene, diesel fuel, aviation fuel (Jet A.1), that of kerosene -diesel mixtures at different proportions and that of aviation fuel (Jet A.1)-diesel mixtures at various percentages. The results of the analysis reveal that soots formed by combusting kerosene, diesel, aviation fuel (Jet A.1) and their respective mixtures have electrical resistivity values ranging from 3.516 x 10-1Ωm to 1.836 x 10-1 Ωm . Soot from diesel fuel has the lowest value whereas soot from kerosene has the highest value of electrical resistivity. The obtained values are within the range of electrical resistivity values for materials classified as semiconductors. Electrical resistivity varies non-linearly with percentage composition of mixture constituents for soot formed by combusting kerosene-diesel mixture or aviation fuel (Jet A.1)-diesel mixture. Soot produced by combustion of pure diesel fuel has less resistivity value, indicating higher conductivity than soot obtained from the burning of aviation fuel whereas soot got from the combustion of kerosene exhibits higher electrical resistivity value than the former. This work has provided a database on the electrical resistivity values of soot (kerosene, diesel fuel, aviation fuel (Jet A.1)) formed as a result of combustion of some fuels and their mixtures for probable utilization by electrical, electronics and petroleum industries. Such database is being reported for the first time, hence making this research work a novel.