Journal articles: 'Surface physic'

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Yakub, Ibrahim, Masita Mohammad, and Zahira Yaakob. "Effects of Zinc Chloride Impregnation on the Characteristics of Activated Carbon Produced from Physic Nut Seed Hull." Advanced Materials Research 626 (December 2012): 751–55. http://dx.doi.org/10.4028/www.scientific.net/amr.626.751.

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Activated carbon was developed from physic nut seed hull through chemical activation using zinc chloride. The characteristics of raw physic nut seed hull as well as char and activated carbon from physic nut seed hull were obtained to study the effects of ZnCl2 impregnation. The comparisons of the characteristics that included elemental composition, surface morphology, surface area, surface functional groups and zeta potential were made on the three samples. The study found that ZnCl2 had positive effects towards developing activated carbon including increasing the carbon content, surface area and pore volume besides improving the microporosity and surface charge distribution of the carbon.

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Wisha, Ulung Jantama, Semeidi Husrin, and Gegar Sapta Prasetyo. "Hydrodynamics of Bontang Seawaters: Its Effects on the Distribution of Water Quality Parameters." ILMU KELAUTAN: Indonesian Journal of Marine Sciences 21, no. 3 (August 29, 2016): 123. http://dx.doi.org/10.14710/ik.ijms.21.3.123-134.

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Bontang is a crowded with residential and industrial activities which produce heat waste into surrounding waters. This condition may cause environmental problems, and changes in water condition. Knowledge about dynamics of physic and chemical waters condition in Bontang city is very important as an effort to address environmental issues as part of coastal zone management and protection. The aim of this research is to understand hydrodynamic characteristics (tide and current) and the influence to distribution of physics and chemical in Bontang waters base on primary data (current and tide during one month, physics and chemicals waters data taken by in situ) and secondary data (bathymetry and tide forecasting). Hydrodynamic simulation is based on MIKE 21 and supported by CD-Oceanography and WR plot. The results show that the current is dominant move toward the Southwest and Northeast with current speed ranged from 0-0,22 m.s-1. The results of hydrodynamic simulation in the surface water show that the current move base on tide movement with current speed ranged from 0-0,24 m.s-1. The results of physic and chemical concentration is analysed by ArcGIS 10 to know spatial distribution of all parameters. Surface temperature ranged from 29-31,8oC, surface density ranged from 20-20,6 ppm, salinity ranged from 33,1-33,5 ppm, dissolve oxygen concentration ranged from 0,078-0,11 ppm. Distribution of all physic and chemical parameters is influenced by current and tide movement. Keywords: current, numerical model, water quality, Bontang waters

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Grigorieva, Iya Yu, Andrey V. Morozov, and Marina A. Gladchenko. "PHYSICO-CHEMICAL PROCESSES OCCURRING ON THE SURFACE OF QUARTZ SAND DURING CONTAMINATION AND THEIR IMPACT ON THE PHYTOTESTING RESULTS." Gruntovedenie 2, no. 19 (2022): 27–39. http://dx.doi.org/10.53278/2306-9139-2022-2-19-27-39.

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Contamination of sandy soils with liquid hydrocarbons (oil and products of its processing), along with salinization, is a characteristic process developed in vast territories associated with oil production. On the example of model experiments using natural quartz sand, the influence of physic-chemical processes on the growth and development of higher plants during fitotesting is considered. The observed physico-chemical processes occur when liquid hydrocarbon and salt pollution enter the soil. We have shown the multidirectional influence of several combinations of pollutants and their amount on the biological parameters of the test culture of white mustard (Sinapis alba L.). Based on the analysis of theoretical concepts, a possible mechanism for regulating the processes occurring at the phase interface when the used combinations of pollutants enter the studied soil system is described. It is suggested that the main contribution to the development of physic-chemical processes in the investigated sand system will be made by the presence of amorphous silica

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Danchenko, Yuliya, Artem Kariev, Vladimir Lebedev, Elena Barabash, and Tatyana Obizhenko. "Physic-Mechanical Properties of Composites Based on Secondary Polypropylene and Dispersed of Plant Waste." Materials Science Forum 1006 (August 2020): 227–32. http://dx.doi.org/10.4028/www.scientific.net/msf.1006.227.

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The physic-mechanical properties of filled composites based on secondary polypropylene are investigated. As fillers the dispersed wastes of processing of agricultural plants - buckwheat and oat husk, as well as needles flour and wood flour were used. Water absorption, abrasion, impact strength and bending strength of composites were investigated. It has been proven that oat and buckwheat husks can be effectively used in composites based on secondary polypropylene and replace traditional wood fillers. It has been shown that the physic-chemical properties of the filled composites depend on the structure and physicochemical interactions on the phase separation surface, as well as on the surface properties of the filler particles. It is established that for the production of filled composites with improved physic-mechanical characteristics it is necessary to use fillers with small specific surface and concentration of surface functional groups, and the acid-base characteristic of the surface should be closer to neutral. It is shown that these conditions provide for the formation of a uniform structure of the filled composite with less internal stresses.

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Pechyen, Chiravoot, Duangdao Aht-Ong, Duangduen Atong, and Viboon Sricharoenchaikul. "Physicochemical Properties of Carbons Prepared from Physic Nut Waste by Phosphoric Acid and Potassium Hydroxide Activations." Materials Science Forum 561-565 (October 2007): 1719–22. http://dx.doi.org/10.4028/www.scientific.net/msf.561-565.1719.

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Char derived from pyrolysis of physic nut waste at 400-800°C was used for the preparation of activated carbon by chemical impregnation of phosphoric acid and potassium hydroxide. The original char exhibited the BET surface area in the range of 120-250 m2·g-1. The surface area increased to 480 and 532 m2·g-1 when activated with H3PO4 and KOH, respectively. Equilibrium adsorption data was found to be best represented by the Langmuir isotherm with maximum monolayer adsorption capacity of 560.13 mg·g-1 at 30°C. The adsorption capacity of the physic nut residue activated carbon was comparable to commercial activated carbon.

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Escalante-Gutiérrez, Danae Carolina, Eduardo Ordóñez-Regil, José Ortíz-Landeros, and María Guadalupe Almazán-Torres. "Sorption of U(VI) onto ZrSiO4 gamma irradiated and functionalized with phytic acid." Radiochimica Acta 108, no. 11 (November 26, 2020): 847–57. http://dx.doi.org/10.1515/ract-2020-0018.

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AbstractIn the suitability assessment of candidate materials as engineering barriers for a Deep Geological Repository (DGR), new studies concerned with zirconium silicate have been carried out. The zirconium silicate extracted from beach sand, was submitted to gamma irradiation in order to evaluate its structural stability and then functionalized with phytic acid (IP6) and measured its sorption capacity vis-a-vis uranium. The purified, irradiated and functionalized material was then characterized by several analytical techniques. The surface parameters including the surface area and density of surface sites were also determined. The results obtained from physic-chemical characterization showed that there were no significant changes in the structure of zirconium silicate after its gamma-irradiation. These results are consistent with those of sorption experiments. Uranium (VI) sorption capacity of zirconium silicate is increased in the presence of phytic acid and remained constant after its exposition to high doses of gamma-radiation (10 and 30 MGy). These results show that the IP6-functionalized zirconium silicate can be used as engineering barriers for a DGR.

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Adam, A. M., P. Petkov, M. Ataalla, Haifa Alqannas, Bandar Alruqi, and Abeer Altowyan. "Structure, thermal and physic-chemical properties of some chalcogenide alloys." Thermal Science, no. 00 (2022): 195. http://dx.doi.org/10.2298/tsci221001195a.

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Bulk products of crystalline Bi2Se3-xTex alloys (x =0.0, 0.1, 0.3, 0.5) were prepared using simple melting synthesis. Crystalline features, microstructure and surface morphologies of the synthesized samples were examined via x-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive x-ray spectrometer. Elemental distribution was studied by energy dispersive analysis of X-ray (EDAX) spectroscopy. Polycrystalline of rhombohedral crystal structure was observed for the concerned samples. Perfect crystallinity and micro-scalability of the prepared were also reflected by the physic-chemical properties of each sample. Thermal behavior was studied throughout differential scanning calorimetry and thermogravimetric analysis showing that the samples are of high stability over high temperature range. Physic-chemical properties were determined in terms of experimental density. These properties were compactness value, molar volume and the percentage of free volume. Density of Bi2Se3 alloy was obtained at 7.37 gm/cm3. Te doping enhanced the density of the Bi2Se3-xTex system. The most Te doped alloy showed density of 9.018 gm/cm3. All other physic-chemical properties showed strong dependence on the Tea amounts in the system.

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Perperi, Liudmyla, Vladimir Gugnin, and Ganna Goloborodko. "SIMULATION MODELING OF THE PROCESS OF DETERMINATION OF SURFACE ROUGHNESS PARAMETERS USING COMPUTER MEASURING TECHNOLOGIES." Bulletin of the National Technical University «KhPI» Series: New solutions in modern technologies, no. 1(11) (May 18, 2022): 30–37. http://dx.doi.org/10.20998/2413-4295.2022.01.05.

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Modern trends in higher education are aimed at the fact that the educational process should become more dynamic and flexible, including the training of engineering specialists in higher educational institutions. During the pandemic caused by COVID-19, most institutions switched to distance learning, in connection with this, the use of virtual instruments created using the LabVIEW graphical programming environment is of particular relevance for practical and laboratory work. Such instruments allow you to conduct classes remotely. The article describes the designed virtual instrument for simulation modeling of the process of determining the surface roughness parameters. To implement this task, a model for calculating the surface roughness parameters is proposed, which takes into account the influence of the geometric parameters of the metal cutting tool and the physic of cutting process during workpiece processing. The modeling process of roughness measurement is carried out in two stages. At the first stage, the movement of the sensor of device the along the scanned surface and the sound of the device drive are simulated. At the second stage, the surface roughness parameters are calculated. The surface roughness profile is a superposition of the theoretical profile which is obtained by copying the profile of the cutting tool tip on the machined surface and random distortion of the profile due to the physic of cutting process. For the purpose of obtaining the coordinates of the theoretical profile points of the workpiece after processing it, an algorithm has been developed for calculating the current position of the profile point depending on the ratio of the feed values and the curvature radius tip of the cutting tool. Changing the position of the current point of the theoretical surface profile due to the impact of the physic of cutting process is taken into account by introducing random oscillations superimposed on the surface profile, which are generated by a random number generator according to the law of equal probability. A technique for processing an array of profile points coordinates to obtain surface roughness numerical parameters Rz, Ra and Rmax is described. The use of computer measuring technologies for solving tasks in the field of engineering using information and measuring equipment allows students to develop the skills to perform technical measurements, receive, analyze and critically evaluate the obtained measurement results

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Guo, Hai Fu, Xiang Li, Zhi Sheng Chen, Peng Yan, and Shu Min Li. "Preparation and Characterization of Rare Earth Solid Superacids SO₄^2-/TiO₂-SnO₂-Dy₂O₃." Advanced Materials Research 287-290 (July 2011): 1659–65. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.1659.

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A new rare earth solid superacids catalyst SO42-/TiO2-SnO2-Dy2O3 was prepared by coprecipitation-impregnating method, and the optimum preparation conditions were obtained. The physic- chemical properties of the catalyst was characterized by FTIR, TG-DTA, XRD and BET. The results showed the prepared catalyst is superacid with good thermal stability and high specific surface area. The sulfuric groups were proved to be chelated and bridgingly connected on the surface of the catalyst.

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Masyuk, A. S., D. S. Katruk, and V. Ye Levytskyi. "Modified polyvinyl chloride composites with metal-containing polymer-silicate fillers." Chemistry, Technology and Application of Substances 4, no. 1 (June 1, 2021): 186–90. http://dx.doi.org/10.23939/ctas2021.01.186.

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The influence of the nature of the metal-containing polymer-silicate fillers on morphology, surface hardness, Vicat softening point and elastic-plastic properties of PVC plasticates has been researched. The influence of polymer-silicate fillers on physic-mechanical and thermal properties and the conditions directional regulation of technological and operational properties of modified composites has been established.

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MIAO, ZHENHUA, ZHENG GONG, ZHIDAN FANG, and ZHICHUAN NIU. "CORRUGATED SURFACES FORMED ON GaAs (331)A SUBSTRATES: THE TEMPLATE FOR LATERALLY ORDERED InGaAs NANOWIRES." International Journal of Nanoscience 05, no. 06 (December 2006): 757–62. http://dx.doi.org/10.1142/s0219581x0600511x.

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Morphology evolution of high-index (331) A surfaces during molecular beam epitaxy (MBE) growth have been investigated in order to uncover their unique physic properties and fabricate spatially ordered low dimensional nanostructures. Atomic Force Microscope (AFM) measurements have shown that the step height and terrace width of GaAs layers increase monotonically with increasing substrate temperature in conventional MBE. However, this situation is reversed in atomic hydrogen-assisted MBE, indicating that step bunching is partly suppressed. We attribute this to the reduced surface migration length of Ga adatoms with atomic hydrogen. By using the step arrays formed on GaAs (331) A surfaces as the templates, we fabricated laterally ordered InGaAs self-aligned nanowires.

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Yao, Jian Guo, Li Jie Ma, Su Fang Fu, Zhan Kui Wang, and Jian Xiu Su. "A Chemism Analysis of Alkali in the Chemical Mechnical Polishing Process of SiC Substrate." Advanced Materials Research 1027 (October 2014): 208–12. http://dx.doi.org/10.4028/www.scientific.net/amr.1027.208.

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In this study, according to physic-chemical characteristic of the SiC crystals, we analyzed and researched the role of pH modifier in SiC crystal substrate chemical mechanical polishing and the surface after polishing. We used different polish agents which was made up with inorganic and organic bases to experiment, and then analyzed the results. The parameters of the polishing specimen, such as the removal rate of material, surface scanning and the roughness, were analyzed and used to determine the different pH modifiers played different roles in the stability of polish agents and surface quality of the specimen.

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Gomes Junior, Daniel Gonçalves, Rubismar Stolf, José Geanini Peres, Victor Meriguetti Pinto, and Klaus Reichardt. "Soil Physical Quality of Brazilian Crop Management Systems Evaluated with Aid of Penetrometer." Journal of Agricultural Science 8, no. 6 (May 10, 2016): 120. http://dx.doi.org/10.5539/jas.v8n6p120.

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Crop management affects soil attributes as well as its quality. We evaluated the following soil physical attributes: saturated hydraulic conductivity (K0), soil resistance (RP) and soil bulk density (BD), in Araras-SP, Brazil. Areas with sugarcane (Saccharum officinarum), soybean (Glycine max), physic nut (Jatropha curcas L.) and native forest presented an increase of soil compaction in the 0.10 m surface layer for the three attributes in a following order: native forest <physic nut < soybean < sugarcane. Significant regressions were obtained for RP × K0; BD × K0 and BD × RP. Penetrometer measurements were essential to indicate differences among areassugarcane, native forest, physic nut and soybean; but for the measurements of K0, only between sugarcane and native forest. RP measurements confirm anthropogenic changes in the soil profile up to the 0.3 m depth. In the “Canarache soil resistance classification” soils showed “low resistance” “without limitations to root development” for native forest and physic nut; “medium resistance” for soybean area with “some limitations to root development” and “high resistance” for sugarcane with “limitations to root development”. The use of penetrometers is discussed in relation to the readiness of field measurements.

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Yuliusman, Mufiid Fatkhurrahman, Fadel Al Farouq, Salma Amaliani Putri, Samson Patar Sipangkar, and Nasruddin. "Modified Activated Carbon Using NiO for Natural Gas Storage." Materials Science Forum 1000 (July 2020): 311–17. http://dx.doi.org/10.4028/www.scientific.net/msf.1000.311.

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The technology of natural gas adsorbed can be called Adsorbed Natural Gas (ANG) technology use porous adsorbents to adsorb natural gas. The material is activated carbon (AC), which has a large specific surface area. Activated carbon made from cassava peel waste because of abundance as agricultural waste in Indonesia. Cassava peel has a high cellulose and lignin content. Cassava peel through the carbonization process with furnace temperature 500 ° C in vacuum condition for 1.5 hours. Then, chemical activation with a different activator agent KOH and NaOH by mass ration (3:1). After that, physic activation with N2 and CO2 gas of 150 mL/minute using temperature muffle furnace 750 ° C. Product of physic activation modified using (Ni (NO3)2). Characterization of activated carbon performed with iodine test, SEM, EDX, adsorption, and desorption testers. The best of activated carbon is activated carbon impregnated KOH and with physic activation at 750 ° C, which has 612 mg / g of iodine number. Then, after activated carbon modified using (Ni (NO3)2) has the best performance with 1% NiO, has 662 mg / g of iodine number, and 657 m2 / g of SBET. Then, activated carbon through adsorption and desorption test by ANG technology has 0.02928 kg/kg of adsorption capacity and 39.17% of desorption percent.

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Lu, Fa Liang, and Jin Li. "Research on Performance of Road Application of Converter Bituminous Steel-Slag Mixture of Jigang Group Co. Ltd." Applied Mechanics and Materials 178-181 (May 2012): 1161–70. http://dx.doi.org/10.4028/www.scientific.net/amm.178-181.1161.

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To detect the chemical composition and physic-mechanical properties of converter steel slag of Jigang Group Co., Ltd and evaluate its feasibility as aggregate of the bituminous mixture. Prepare three kinds of AC20 bituminous mixtures by all using the steel slag as aggregate, by partially using the steel slag as aggregate and by all using macadam as aggregate respectively, and analyze the physic-mechanical properties of such three kinds of bituminous mixtures. The test analysis results prove that the high-temperature stability, low-temperature crack resistance and fatigue property of the bituminous mixture with all steel slag as aggregate or partial steel slag as aggregate are superior to those of macadam mixture. Although its water stability is a little bad, it still can meet the specification requirements, and it is suggested to be used widely in the middle and lower surface layers of pavement structure layer.

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Wu, Guo Zhong, En Yue Guo, Han Bing Qi, Ying Ming Zhou, and Dong Li. "The Impact Analysis on Crude Oil Phase Change to the Migration of Buried Oil Pipelines Leakage Pollution." Applied Mechanics and Materials 675-677 (October 2014): 341–44. http://dx.doi.org/10.4028/www.scientific.net/amm.675-677.341.

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This paper established mathematic and physic model of buried oil pipelines leaking in porous media of soil. Make use of FLUENT software to simulate crude oil phase change and non-phase change in the soil of cold regions. The result shows that: The temperature over the leakage hole of phase change diffusion process is higher than not considering phase change. The oil phase diffuse to the earth’s surface needs more time. And the speed diffusing to the underground is basically same. The earth surface temperature’s variation of leakage process without crude oil phase change lags behind the process considering phase change.

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Sachuk, Olena. "SYNTHESIS OF СеО2–МоО3 CATALYSTS OF SELECTIVE ETHANOL OXIDATION BY NON-TRADITIONAL METHODS." Ukrainian Chemistry Journal 85, no. 10 (October 16, 2019): 91–101. http://dx.doi.org/10.33609/0041-6045.85.10.2019.91-101.

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The influence of mechanochemical (MChT) and ultrasonic (UST) treatment on physic-chemical properties of СеО2-МоО3=1:1 composition was studied. The prepared samples were characterized by methods of XRD, ESR, N2 adsorption, SEM and TEM methods. The catalytic properties of obtained samples were studied in selective ethanol oxidation reaction. It was established the increase of specific surface area, decrease crystallites size and nanostructures formation of type “core-shell” due to MCh and US treatment. The change of physico-chemical properties of the compositions as a result of their mechano- and sonochemical treatment leads to increase their catalytic properties. The samples obtained after MCh and US treatments demonstrate very promising results in oxidative dehydrogenation of ethanol to acetaldehyde and the treated compositions permit to obtain the acetaldehyde selectivity equal 97 % at reaction temperature about 200ºC. It was shown that mechno- and sonochemical treatments of oxide mixture allow to obtain a high acetic aldehyde yield (97%) at 215°C and productivity on this product 1.8 mol/kg·h.

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Litvin, Yu A., A. V. Kuzyura, and E. B. Limanov. "The role of garnetization of olivine in olivine-diopside-jadeite system in the ultramafic-mafic evolution of the upper-mantle magmatism (experiment at 6 GPa)." Геохимия 64, no. 10 (November 19, 2019): 1026–46. http://dx.doi.org/10.31857/s0016-752564101026-1046.

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Peritectic mechanisms, controlling fractional ultrabasic-basic evolution of the upper mantle magmatism and genesis of the peridotitepyroxeniteeclogite rock series, are substantiated in theory and experiment. Melting phase relations of a differentiated mantle material are studied with polythhermal section method in the multicomponent olivineclinopyroxene/omphacitecorundumcoesite system with boundary compositions duplicated these of peridotitic and eclogitic minerals. The peritectic reaction of orthopyroxene and melt with formation of clinopyroxene (the opthopyroxene clinopyroxenization reaction) has been determined at a liquidus surface of the ultrabasic olivineorthopyroxeneclinopyroxenegarnet system. As a result of the reaction the temperature-regressive univariant curve olivine + clinopyroxene + garnet + melt is formed. A further evolution of magmatism has experimentally studied at 6 GPa in the ultrabasic-basic olivinediopsidejadeitegarnet system with changeable compositions of the diopsidejadeite solid solutions (controlling the clinopyroxene omphacite mineralogy). Peritectic reaction of olivine and melt with formation of garnet was established on the liquidus surface of the ternary olivinediopsidejadeite system as the mechanism of olivine garnetization and going to the univariant curve omphacitegarnetmelt with formation of bimineral eclogites. Structure of the liquidus surface for the olivinediopsidejadeitegarnet system is inferred, and its role as a physic-chemical bridge between ultrabasic olivinebearing peridotitepyroxenitic and basic silica-saturated eclogitic compositions of the garnetperidotite facies matter. The new experimental physic-chemical results reveal the genetic links between ultrabasic and basic rocks as well as mechanisms of the uninterrupted fractional magmatic evolution and petrogenesis from the olivinebearing peridotitepyroxenitic to silica-saturated eclogite-grospyditicrocks. This provides an explanation for the uninterrupted composition trends for rock-forming components in clinopyroxenes and garnets of the differentiated rocks of the garnetperidotite facieis.

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Olkowska, Ewa, Marek Ruman, and Żaneta Polkowska. "Occurrence of Surface Active Agents in the Environment." Journal of Analytical Methods in Chemistry 2014 (2014): 1–15. http://dx.doi.org/10.1155/2014/769708.

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Due to the specific structure of surfactants molecules they are applied in different areas of human activity (industry, household). After using and discharging from wastewater treatment plants as effluent stream, surface active agents (SAAs) are emitted to various elements of the environment (atmosphere, waters, and solid phases), where they can undergo numerous physic-chemical processes (e.g., sorption, degradation) and freely migrate. Additionally, SAAs present in the environment can be accumulated in living organisms (bioaccumulation), what can have a negative effect on biotic elements of ecosystems (e.g., toxicity, disturbance of endocrine equilibrium). They also cause increaseing solubility of organic pollutants in aqueous phase, their migration, and accumulation in different environmental compartments. Moreover, surfactants found in aerosols can affect formation and development of clouds, which is associated with cooling effect in the atmosphere and climate changes. The environmental fate of SAAs is still unknown and recognition of this problem will contribute to protection of living organisms as well as preservation of quality and balance of various ecosystems. This work contains basic information about surfactants and overview of pollution of different ecosystems caused by them (their classification and properties, areas of use, their presence, and behavior in the environment).

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BEQAJ, Blerina. "ASSESSING THE ENVIRONMENTAL IMPACT OF ROADWAY’S CONSTRUCTION ON ADJACENT WATER RESOURCES: A CASE STUDY OF THE SOUTHERN PART OF ALBANIA." Scientific Journal of Silesian University of Technology. Series Transport 114 (January 1, 2022): 5–13. http://dx.doi.org/10.20858/sjsutst.2022.114.1.

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Water is one of nature’s resources. As urbanisation grows, new roadways and highways are constructed for the transport sector and development. Due to roadway infrastructure, the development of the quality of surface water bodies in close proximity to roads is deteriorating and has become a major environmental challenge. Considered as one of the major nonpoint pollution sources, the construction of new roadways can have short and long-term effects on water quality conditions. This study revealed that road construction activities may be responsible for introducing pollutants in nearby water sources, leading to the deterioration of water quality. The roadway expansion activities affect both the surface and groundwater quality. Furthermore, this study was conducted to assess the effects of a road construction project situated in the southern part of Albania, on physic-chemical parameters of surface water by collecting water samples from Skotini stream. The analysed parameters included pH, dissolved oxygen (DO), biological oxygen demand (BOD5), chemical oxygen demand (COD), electrical conductivity (ECw), total dissolved solids (TDS), salinity, nitrites (NO2-), ammonium (NH4+) and total phosphorus (Ptot). The results revealed that all physic-chemical parameters analysed in the laboratory are between the normal standards classifying these waters as very clean. Further surveillance for quality assessment of water sources near roadway’s construction activities is needed. Various best management practices have been developed and implemented to prevent negative environmental impacts in the transport sector and roadway construction activities. Results of the water quality help strengthen the theory that roadway construction projects in the transport sector, using appropriate best management practices, could yield minimal impact on the overall water quality of surrounding water bodies.

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Coffetti, Denny, Elena Crotti, Gabriele Gazzaniga, Roberto Gottardo, Tommaso Pastore, and Luigi Coppola. "Protection of Concrete Structures: Performance Analysis of Different Commercial Products and Systems." Materials 14, no. 13 (July 2, 2021): 3719. http://dx.doi.org/10.3390/ma14133719.

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The increasing demand for reconstructions of concrete structures and the wide availability on the market of surface protective products and systems could lead to misunderstandings in the decision of the most effective solution. Surface protectors have become increasingly widespread in recent years in concrete restoration interventions thanks to their properties: they are able to protect the substrate from aggressive agents and consequently extend the useful life of the structures. The aim of this article is first of all to present the surface protective treatments available on the market, outlining their strengths and weaknesses. Subsequently, a characterization of seven different commercial coatings for reinforced-concrete structures is provided, taking into account chemical nature, fields of use and effectiveness, both in terms of physic and elastic performance and resistance to aggressive agents that undermine the durability of the treated concrete elements.

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KHEIRABADI, Fouad, Hooshmand ALIZADEH, and Hossein NOURMOHAMMADZAD. "Improving Climatic Comfort of Citizens by Adjusting the Orientation and Extension of Physics of City Squares: Case Study of Yazd." Chinese Journal of Urban and Environmental Studies 05, no. 02 (June 2017): 1750012. http://dx.doi.org/10.1142/s2345748117500129.

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The heat of the earth is provided by solar radiation. A change in the angle of solar radiation and the surface of the earth causes changes in the ambient temperature. Sometimes, these changes reduce climatic comfort of human beings. Climatic comfort is established when there is a balance between excreted and absorbed temperatures of the skin of the body. Orientation and extension rates of physics of squares relative to the geographical north influence the amount of received direct sunlight in different months. Relevant studies show that the squares of the city of Yazd reduce the climatic comfort of its citizens; moreover, the physics of Yazd's squares apply various extension rates, which led to high building costs to citizens and relevant organizations. This study, by using the correlation method and R software, measures different orientation and extension rates of physics of squares in Yazd. It analyzes two models with orientation and physical extension as variables and evaluates the shade and sunlight in the space. The results reveal significant differences between desirable and undesirable options. Considering the climatic comfort of space users and residents at the same time, a rectangle with an extension ratio of one to several and the north-south orientation, making the lowest facade face the south, is the most appropriate physic for city squares.

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Zhao, Jun Wen, Shu Sen Wu, Guang Ze Dai, Jing Han, and Xing Min Huang. "Physic Simulation of Slurry Preparation by Ultrasonic Vibration in Semisolid Metal Processing." Materials Science Forum 704-705 (December 2011): 1279–83. http://dx.doi.org/10.4028/www.scientific.net/msf.704-705.1279.

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In current research, a series of visualization experiments simulating the action of ultrasonic vibration (UV) in metal slurry preparation process on fluid flow, grain nucleation and growth as well as its interaction with viscosity of fluids were conducted. In these visualization experiments, the metal slurry maker was substituted by a transparent cup while the liquid and semisolid slurry of metal were replaced by other fluids or mixture system with similar characteristics. Scaled-up UV was applied to the liquid or mixture systems. The simulation shows that UV can roll up the particles at the bottom of the cup and make the liquid convection intense below the radiating surface of sonotrode while weak above it. UV can break dendrites rapidly and distribute them in melt. High viscosity reduces the actual power transmitted into liquid, and higher viscosity requires higher inception power of UV.

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Guo, Wei, Bin Gao, Gui Yun Tian, and Dan Si. "Physic perspective fusion of electromagnetic acoustic transducer and pulsed eddy current testing in non-destructive testing system." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2182 (September 14, 2020): 20190608. http://dx.doi.org/10.1098/rsta.2019.0608.

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Comprehensive non-destructive testing (NDT) for pipelines is a critical and challenging task. This paper proposes a novel physic perspective fusion NDT method of electromagnetic acoustic transducer (EMAT) and pulsed Eddy current testing (PECT) for detecting hybrid defects. This transceiver-integrated fusion sensor structure can simultaneously excite ultrasound and pulsed eddy current. Therefore, the generated ultrasound is applied to detect deep defects, while the eddy current detects surface defects. The theoretical derivation of EMAT and PECT fusion mechanism has been developed for analysis and interpretation of the results. In addition, numerical simulation on the detection of hybrid defects including surface defects with different width, depth and multiple bottom-thinning defects has been conducted. Experiments on both ferromagnetic and non-ferromagnetic material verify the feasibility of composite detection. Finally, tests have been validated on pipeline with weld defects, and the results show that the composite inspection method is capable of monitoring thickness variations and inspecting surface defects. This article is part of the theme issue ‘Advanced electromagnetic non-destructive evaluation and smart monitoring’.

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Grinchik, N. N., and Yu N. Grinchik. "Fundamental Problems of the Electrodynamics of Heterogeneous Media." Physics Research International 2012 (April 8, 2012): 1–28. http://dx.doi.org/10.1155/2012/185647.

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The consistent physic-mathematical model of propagation of an electromagnetic wave in a heterogeneous medium is constructed using the generalized wave equation and the Dirichlet theorem. Twelve conditions at the interfaces of adjacent media are obtained and justified without using a surface charge and surface current in explicit form. The conditions are fulfilled automatically in each section of counting schemes for calculations. A consistent physicomathematical model of interaction of nonstationaly electric and thermal fields in a layered medium with allowance or mass transfer is constructed. The model is based on the methods of thermodynamics and on the equations of an electromagnetic field and is formulated without explicit separation of the charge carriers and the charge of an electric double layer.

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Dou, Fangjia, Xiaolei Lv, and Huiming Chai. "Mitigating Atmospheric Effects in InSAR Stacking Based on Ensemble Forecasting with a Numerical Weather Prediction Model." Remote Sensing 13, no. 22 (November 19, 2021): 4670. http://dx.doi.org/10.3390/rs13224670.

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The interferometric synthetic aperture radar (InSAR) technique is widely utilized to measure ground-surface displacement. One of the main limitations of the measurements is the atmospheric phase delay effects. For satellites with shorter wavelengths, the atmospheric delay mainly consists of the tropospheric delay influenced by temperature, pressure, and water vapor. Tropospheric delay can be calculated using numerical weather prediction (NWP) model at the same moment as synthetic aperture radar (SAR) acquisition. Scientific researchers mainly use ensemble forecasting to produce better forecasts and analyze the uncertainties caused by physic parameterizations. In this study, we simulated the relevant meteorological parameters using the ensemble scheme of the stochastic physic perturbation tendency (SPPT) based on the weather research forecasting (WRF) model, which is one of the most broadly used NWP models. We selected an area in Foshan, Guangdong Province, in the southeast of China, and calculated the corresponding atmospheric delay. InSAR images were computed through data from the Sentinel-1A satellite and mitigated by the ensemble mean of the WRF-SPPT results. The WRF-SPPT method improves the mitigating effect more than WRF simulation without ensemble forecasting. The atmospherically corrected InSAR phases were used in the stacking process to estimate the linear deformation rate in the experimental area. The root mean square errors (RMSE) of the deformation rate without correction, with WRF-only correction, and with WRF-SPPT correction were calculated, indicating that ensemble forecasting can significantly reduce the atmospheric delay in stacking. In addition, the ensemble forecasting based on a combination of initial uncertainties and stochastic physic perturbation tendencies showed better correction performance compared with the ensemble forecasting generated by a set of perturbed initial conditions without considering the model’s uncertainties.

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Guo, Shiguang, Jianghua Zhang, Mingxue Shao, Xia Zhang, Yufeng Liu, Junli Xu, Hao Meng, and Yide Han. "Selective adsorption of bovine hemoglobin on functional TiO2 nano-adsorbents: surface physic-chemical properties determined adsorption activity." Materials Research Express 2, no. 4 (April 16, 2015): 045101. http://dx.doi.org/10.1088/2053-1591/2/4/045101.

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Guan, Wei, Jinghai Sun, Xiang Li, and Zhihao Ren. "Unmanned Surface Vessel Steering L2 Gain Robust Control Based on Closed-Loop Shaping Filter." Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University 37, no. 5 (October 2019): 1018–27. http://dx.doi.org/10.1051/jnwpu/20193751018.

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With the introduction of the closed-loop shaping filtering method into the L2 gain robust controller design strategy, a nonlinear robust steering controller for unmanned surface vessel is designed under the planning and control strategy in this paper. The rigorous mathematical analysis and synthesis characteristics of the L2 gain robust control theory and the Lyapunov design method are fully utilized in the controller design process. Furthermore, the concept of the closed-loop shaping filtering based on the classical closed-loop control theory is taken into the controller design strategy. Therefore, the time domain controller design methods integration with the frequency domain controller design strategy are merged togehter to complete the unmanned surface vessel steering controller design in the view of practical engineering and planning and control strategy. Finally, compared with several practical controller design methods in the multi-direction irregular waves, the simulation results show that the proposed steering controller design strategy has concise structure, distinctive physic meanings of the controller parameters and superior comprehensive control performance.

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Lisovskyj, Andrii, and Vladislav Harbar. "PHYSIC-CHEMICAL PROPERTIES OF TYPICAL CHERNOZEMS OF PRYDNISTERSK PODILLYA." SCIENTIFIC ISSUES OF TERNOPIL VOLODYMYR HNATIUK NATIONAL PEDAGOGICAL UNIVERSITY. SERIES: GEOGRAPHY 51, no. 2 (December 5, 2021): 57–64. http://dx.doi.org/10.25128/2519-4577.21.2.7.

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This article analyzes the physic-chemical properties of typical chernozems. According to the methods, a laboratory study was performed. Physic-chemical parameters that are typodiagnostic for subfacial classification division of typical chernozems of the Prydnistersk Podillya are determined. Typical chernozems of the Prydnistersk Podillya are low-humus (2.78–3.98%). With depth, the humus content decreases by an average of 0.2% for every 10 cm, which indicates a uniformly accumulative type of distribution of organic matter in the profile of chernozems. In the same direction, humus reserves are declining. There is a spatial correlation between the humus content and the amount of physical clay in the fine soil. Humic acids predominate in the humus to a depth of 90–100 cm (Sgk: Sfk is 1.12–1.78). The general tendency of relative “fulvatization” of the arable layer as a result of its agrotechnical depletion is noticed. In relation to SGC to total organic C, chernozems of the study area are characterized by a high and very high degree of humification of organic matter. It is highest (62–70%) in the soils of the key section “Humentsi”, decreasing to 52–62% and 43–63% in the western direction. The humic acids of typical chernozems are dominated by calcium humates (GK-2). The largest number of them (29–35%) is concentrated on the contact boundary of humus and carbonate profiles. The convex nature of the distribution curves of the fraction of 2 humic acids and a sharp decrease in its content deeper than 100 cm, indicates their high migration capacity and the possibility of significant deposition of only a significant excess of calcium carbonates. The intensity of migration processes of the GK-2 fraction decreases in the direction of increasing the stiffness of hydrothermal conditions, due to the pulling of carboxylic acid salts closer to the soil surface, supersaturation of the solution with calcium bicarbonate, and as a consequence, increasing the total alkalinity in the humus horizon. The capacity of cation exchange (ECO) of typical chernozems is quite high (29–32 mmol-eq / 100 g of soil) with the dominance of calcium and magnesium cations in the composition of the soil-absorbing complex (GVC). There is a general tendency to increase these indicators in chernozems with low values of SCC of the territory. The pH of the aqueous extract of typical chernozems of the Prydnistersk Podillya increases with depth from weakly acidic in the arable horizon to weakly and medium-alkaline within the carbonate profile. The reasons for such changes in the increase with the depth of the concentration of Ca2 + bicarbonates, which in their dissociation leads to an increase in the amount of hydroxyl ion and increase the alkalinity of the soil. The carbonate profile of typical chernozems is dominated by migratory forms of carbonate neoplasms - mold, carbonate plaque, veins. The vertical curve of carbonate content has an eluvial-illuvial type of profile structure. The content and reserves of carbonates in the 1.5-meter layer of typical chernozems increase from the west (434–714 t / ha) to the east (979–1847 t / ha). Key words: physic-chemical properties, typical chernozems, humic horizon, humic acids, carbonate profile.

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Mansilha, Catarina, Armindo Melo, Deolinda Flores, Joana Ribeiro, João Ramalheira Rocha, Vítor Martins, Patrícia Santos, and Jorge Espinha Marques. "Irrigation with Coal Mining Effluents: Sustainability and Water Quality Considerations (São Pedro da Cova, North Portugal)." Water 13, no. 16 (August 5, 2021): 2157. http://dx.doi.org/10.3390/w13162157.

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Two water effluents that drain from the abandoned coal mine of São Pedro da Cova (NW Portugal) were characterized in terms of their physic-chemical properties and suitability for irrigation purposes. Samples were also collected in a local surface stream, upstream and downstream from the mine drainage points, also used for irrigation by local farmers. Water samples were analyzed for major and minor ions and for trace element concentrations. Sampling campaigns started in 2017 and ended in 2019 and there were 46 water quality parameters tested. There were also proposed all-inclusive indices (the Water Quality Index and the Contamination Index, and also the Trace Element Toxicity Index) based on specific groups of 18 and 17 physic-chemical parameters, respectively, to achieve adequate monitoring requirements for mine effluents and surface water from coalfield. From the physical and chemical aspects of mine water it is inferred that the mine is not producing acid mine drainage. The coal mine water is of medium to high salinity, having almost neutral pH and a high thermal stability during the year, which is a distinguishing feature of the effluents. When compared to international irrigation water quality standards, as Food and Agriculture Organization of the United Nations admissible concentrations, the impacted waters are unsuitable for irrigation. The major outliers to the guidelines were iron, manganese, potassium, magnesium and bicarbonates, being also detected carcinogenic polycyclic aromatic hydrocarbons. Cost-effective ways of monitoring water quality parameters are needed to help control and manage the impact of coal mine effluents that should be treated before releasing into a ditch system that could be then used by local farmers to irrigate their crops.

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CONKA, Dāvis, Līga AVOTINA, Ruta SVINKA, Visvaldis SVINKA, Laris BAUMANE, Anna TRUBACA-BOGINSKA, Valentīna KINERTE, and Gunta KIZANE. "Investigations of Latvian Illite/Kaolinite Clays Irradiated Under Action of Accelerated Electrons." Materials Science 26, no. 1 (November 8, 2019): 99–102. http://dx.doi.org/10.5755/j01.ms.26.1.21446.

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Natural clay is a perspective material for application as sorbents for wastewater treatment as well as for sorption of radionuclides, where the properties of the clays can be changed under influence of ionizing radiation. For application of Latvian illite/kaolinite clays for isotope sorption it is important to characterize the physic-chemical properties of pre-prepared air dried clays. Two fractions of the illite clays were selected. A fraction with grain size 100 μm (SiO2 content 60.9 ± 1.5 wt.%, specific surface area 35 m2/g) and a sand free fraction – 2 μm (SiO2 47.7 ± 1.9 wt.%, specific surface area 38 m2/g). Selected fractions were irradiated with accelerated electrons (5 MeV, ELU-4, Salaspils, absorbed dose up to 500 kGy). Non-irradiated and irradiated clays were analysed with means of Fourier transform infrared (FT-IR) spectrometry.

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Fattah, G., F. Ghrissi, J. Mabrouki, and N. Al-Jadabi. "MODELING AND ASSESSMENT OF THE IMPACT OF LAND USE IN THE WESTERN RIF REGION, MOROCCO, ON WATER QUALITY." International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLVI-4/W5-2021 (December 23, 2021): 225–30. http://dx.doi.org/10.5194/isprs-archives-xlvi-4-w5-2021-225-2021.

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Abstract. The Western Rif is a rural area characterized by rock extraction and agriculture. As a result, the surface of the land in the region is exposed to different sources of contamination which alters the quality of the soil. Leaching of the soil and runoff to surface water may impact the quality of surface water used by local people. A mapping of the land use by GIS of an area located at the level of the western Rif was carried out then an analysis of the interactions between the uses of the land; the practices, the quality of the surface layer of the soil and the quality of the water were made. Thanks to the processing of satellite images and to samples on the ground and assays of the physic-chemical parameters of soils and water (T °, pH, MES, turbidity, Nitrate, nitrite, phosphorus, nitrogen, etc.). The results of these analyzes revealed that these activities lead to an alteration in the quality of the surface layer of the soil, its characterization of which changes depending on the land use. Surface water is endowed with the components identified in the soil. This reveals that land use has generally negative physical and chemical impacts on surface waters.

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Miramond, T., Pascal Borget, Serge Baroth, and Daculsi Guy. "Comparative Critical Study of Commercial Calcium Phosphate Bone Substitutes in Terms of Physic-Chemical Properties." Key Engineering Materials 587 (November 2013): 63–68. http://dx.doi.org/10.4028/www.scientific.net/kem.587.63.

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Physico-chemical characteristics impact directly or indirectly the bioactive properties of biomaterials, it is then essential to correlate it with their effect in vivo. A panel of biomaterials available on the market, based on Hydroxyapatite (HA) and Tricalcium phosphate (β-TCP) is studied in terms of surface area, hydrophilicity, porosity, zeta potential, crystalline phases and density. This study highlights the dispersity of commercial calcium phosphates (CaP) properties, and demonstrates how the quality criteria required for such bone substitute based on biomimicry concept, whose pores distribution is certainly the more relevant, are often incompletely or not respected according to literature.

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Jakubaszek, Anita. "Nitrogen and Phosphorus Content in Constructed Wetlands." Civil and Environmental Engineering Reports 30, no. 2 (June 1, 2020): 247–57. http://dx.doi.org/10.2478/ceer-2020-0030.

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AbstractHigh effectiveness of organic pollutants and nutrients removal is achieved in biological wastewater treatments plants – in case of proper exploitation of these objects. Nitrogen and phosphorus transformation or removal depends on many physic – chemical and biochemical conditions, deposit and environmental factors. A rule for treating wastewater consists in decomposition of organic compounds included in wastewater in water-soil environment. Removing contaminations is performed as a result of sorption of contaminations, bio-chemical oxidation-reduction reactions and biological activity of soil microorganisms and hydrophyte flora. The research has been carried out in the constructed wetland in Małyszyn (1300 EP). The treatment plant operates in horizontal system, with under-surface flow of wastewater.

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Goroshkina, Ulyana V., Olesya A. Laput, and Irina A. Kurzina. "Effect of ion-plasma treatment on the surface physic-chemical properties of materials based on polylactide and hydroxyapatite." Vestnik Тomskogo gosudarstvennogo universiteta. Khimiya, no. 19 (September 1, 2020): 45–50. http://dx.doi.org/10.17223/24135542/19/5.

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Bao, Yan, Jiajia Guo, Jianzhong Ma, Pan Liu, Qiaoling Kang, and Jing Zhang. "Cationic silicon-based gemini surfactants: Effect of hydrophobic chains on surface activity, physic-chemical properties and aggregation behaviors." Journal of Industrial and Engineering Chemistry 53 (September 2017): 51–61. http://dx.doi.org/10.1016/j.jiec.2017.03.045.

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Панайоти, Владимир, and Vladimir Panayoti. "ANALYSIS OF SOLID LUBRICATION EFFECT UPON SURFACE HARDENING OF HIGH-SPEED STEEL TOOLS DURING SHARPENING." Bulletin of Bryansk state technical university 2016, no. 2 (June 30, 2016): 41–45. http://dx.doi.org/10.12737/20242.

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The mechanism of highspeed steel surface har-dening during grinding is considered, the system for a complex investigation of physic-stress-strain properties of surface layers is developed and the investigation results at the oil use are presented. It is determined that the value and degree of coldhardening of a high-speed steel surface layer is a thermo-dependent process, the mechanism of structural and phase changes is analyzed and the efficiency of solid lubrication use in working process is shown. Oil coating on an abrasive tool during results in a natural decrease of cold-hardening at all values of a crossfeed motion. This is caused both by cutting force decrease, and by the decrease of grinding temperature because of the friction force reduction at the interaction of high-speed steel with an oiled disk. The regularities of austenite quantity changes after steel grinding under different conditions confirm phase changes influence upon a value and a degree of cold-hardening. The results obtained allow choosing reasonably cutting modes and characteristics of cBN disks at oil coating during sharpening.

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Alani, R., and P. R. Swann. "Chemically assisted ion-beam etching in a low-angle ion mill." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 718–19. http://dx.doi.org/10.1017/s0424820100149428.

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In conventional ion mills, chemically assisted ion beam etching (CAIBE) has become an establish method for TEM specimen preparation of certain materials. CAIBE employs a reactive gas which brought in contact with the specimen through a jet assembly, while an inert gas ion beam is directed on the same area. Therefore, thinning occurs by the combination of chemical reaction and physic sputtering, which leads to enhanced thinning rates. The reactive gas used in the CAIBE technique can generated from a solid source which sublimes e.g. iodine or it can be injected directly from a pressuriz gas bottle e.g. nitrous oxide. Nitrous oxide in combination with a xenon ion beam has been used from cross sectioning TEM specimens of diamond films on silicon.It is well known that indium-containing compound semiconductors develop indium islands on the surface when thinned with an argon ion beam. It is believed that preferential sputtering enriches the surface with indium and that heating by the ion beam melts the indium which then agglomerates to for small globules on the surface.

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Osho, Michael, Tope Popoola, Tolulope Adeleye, and Christianah Adetunji. "Response surface methodology for optimal immobilization of Aspergillus niger ATCC 1015 lipase by adsorption method." International Journal of Biological Research 4, no. 1 (April 19, 2016): 56. http://dx.doi.org/10.14419/ijbr.v4i1.6008.

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Optimization of Vegetable Sponge (Luffa aegyptiaca) (VS) - immobilization conditions of Aspergillus niger ATCC 1015 lipase on Solid State Fermentation (SSF) was carried out using Response Surface Methodology (RSM). Four independent variables (temperature, pH, enzyme loading and enzyme stability) were optimized using Central Composite Design of RSM for lipase production in a solid rice bran-physic nut cake medium. The optimal immobilization conditions obtained were 45 °C, pH 7.0, 2.5% (w/v) enzyme loading and 32.5% (v/v) enzyme stability (using glutaraldehyde as crosslinking agent) resulted into lipase activity of 98.6 Ug-1. The result demonstrates the potential application of vegetable sponge under SSF system in immobilizing lipase, thus contributed to efficiency of the use of this biomatrix as an immobilizing agent. The statistical tools employed predicted the optimal conditions for the production of the immobilized lipase thus revealing the full potential of the support.

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ARDID, M., J. RAMIS, V. ESPINOSA, J. A. MARTÍNEZ-MORA, F. CAMARENA, J. ALBA, and V. SANCHEZ-MORCILLO. "FIRST ACTIVITIES IN ACOUSTIC DETECTION OF PARTICLES IN UPV." International Journal of Modern Physics A 21, supp01 (July 2006): 137–41. http://dx.doi.org/10.1142/s0217751x06033519.

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The first activities related to acoustic detection of particles by DISAO research group in the Univesitat Politècnica de València are described. We are applying some techniques from physic, engineering and oceanographic acoustics to face the high energy neutrino underwater acoustic detection challenge. The work is focused mainly in two topics: design, characterization and calibration of hydrophones, and simulation of the propagation of the signal in the sea. We present also some examples for these two topics: piezoelectric modelling and transducer simulation, calibration of hydrophones using MLS signals, and evaluation of the contribution of the sea surface noise to the deep water noise in the Mediterranean Sea by means of simulations of propagation of sound.

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Edama, N. A., A. Sulaiman, K. H. Ku Hamid, M. N. Muhd Rodhi, Mohibah Musa, and S. N. Abd. Rahim. "Physico-Chemical and Morphological Changes of Sayong Kaolinite Clay Treated with Sulphuric Acid for Enzyme Immobilization." Advanced Materials Research 832 (November 2013): 589–95. http://dx.doi.org/10.4028/www.scientific.net/amr.832.589.

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This study analyzed the effects of sulphuric acid (H2SO4) treatment on pysico-chemical properties and morphological changes of clay obtained from Sg. Sayong, Perak. The clay was ground and sieved to <150μm and treated with different concentrations of H2SO4. The treatment was completed by refluxing the clay with different concentration of H2SO4 (1M, 5M and 10M ) at 100 °C for 4 hours and followed by calcination at 500 °C for 1 hour. The physic-chemical properties and morphological changes of the untreated and treated clay were compared using Surface Area Analyser, X-Ray Diffraction (XRD), Field Emission Scanning Electron Micrograph (FESEM), X-Ray Diffraction (XRD) and Fourier Transformed Infrared Spectroscopy (FTIR). The results showed that acid treatment of 5M increased the surface area from 25 m2/g to 75 m2/g and the pore volume increased from 0.1518 cc/g to 0.3546 cc/g. The nanopore size of the clay decreased from 24.8 nm to 19.4 nm after treated with acid. This can be explained due to the elimination of the exchangeable cations and generation of microporosity. The results of XRF showed SiO2 increased from 58.34% to 74.52% and Al2O3 reduced from 34.6% to 18.31%. The mineral oxides such as Fe2O3, MgO, CaO, K2O and TiO2 also reduced. This concluded that H2SO4 treatment has led to significant removal of octahedral Al3+, Fe3+ cations and other impurities. In conclusion, this study showed the physico-chemical properties and morphology of Sayong clay were improved once treated with H2SO4 and therefore suggests better supporting material for enzyme immobilization.

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Oliveira, Talitha Stella Sant’Ana, Cassiana Bigolin, Laura Cé da Silva, Júlia Machado Menezes, Tainara Amanda Ayres, Gabriela Zimmermann Prado Rodrigues, Vinícius Bley Rodrigues, et al. "Water quality assessment in the region of Vale dos Sinos trough the alternative model Caenorhabditis elegans." Journal of Environmental Analysis and Progress 7, no. 2 (April 19, 2022): 062–72. http://dx.doi.org/10.24221/jeap.7.2.2022.3898.062-072.

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The determination of the condition of river water quality is critical to establishing sustainable water resource management policies. The use of bioindicators tests for the evaluation of water quality is a valuable tool, and the nematode C. elegans is described as a good organism to assess toxicological risks in aquatic and soil environments. The samples of water were collected in three stretches of the Paranhana and Ilha rivers (P1, P2 and P3) in November (spring) of 2018, January (summer) of 2019, April (autumn) of 2019, and August (winter) of 2019. The physic-chemical parameters were analyzed according to the standard methods (Standard Methods for the examination of Water and Wastewater 23rd edition). The nematode strains used are savage lineage N2 and were obtained through the Caenorhabidits Genetics Center (CGC) for the bioindicator test. The development evaluation was verified by the body surface area measurement of 20 nematodes which were quantified thru the ImageJ software. Most of the physic-chemical parameters were within the limits recommended by CONAMA, but aluminum, that presented values ten times higher than the recommended limit. Significant differences were observed in the nematodes development from all the samples when compared to the control group (p<0,001). The analysis of nematode development demonstrated that the bioindicator was sensitive to the research, showing that ecotoxicological assays are important for a more realistic scenario of threats to water quality, and C. elegans allows this assessment to be performed adequately.

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Chu, Rui Zhi, Zhong Cai Zhang, Ya Fei Liu, Xian Liang Meng, Zhi Min Zong, and Xian Yong Wei. "Study on Preparation and Catalytic Properties of Pd/γ-Al₂O₃ Catalysts in One-Step Synthesis of Dimethyl Ether." Applied Mechanics and Materials 66-68 (July 2011): 1404–9. http://dx.doi.org/10.4028/www.scientific.net/amm.66-68.1404.

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A series of Pd/γ-Al2O3 catalysts with different additons of Pd were prepared by impregnation. The effect of calcination condition and Pd loading on catalytic performance of catalysts for one-step dimethyl ether synthesis has been investigated. The physic-chemical performance and structure of Pd/γ-Al2O3 catalysts were characterized by CO-TPD, TGA and nitrogen physisorption. The results show that the dispersion of Pd and the amount of adsorbration on the CO-bridge of Pd could be increased to by the moderate microwave heating on the catalysts, and the catalyst performance can be improved. But a large number of surface acidic sites of Pd/γ-Al2O3 are covered by highly fragmented Pd-grain, it causes DME selectivity reduced. And the excessive Pd can reduce the samples’ surface acid, decrease the dispersion of the metal Pd and block up the pore of γ-Al2O3. The CO conversion rate and DME space-time yield could reach 60.1% and 28.76 mmol·g-1·h-1 respectively at 2% Pd loading, at this time Pd/γ-Al2O3 has a high Pd activity surface and ideal acid sites.

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Yin, Shi Bin, Qiang Qiang Zhu, Li Xiang Yang, Ying Huai Qiang, Fei Huang, and Lin Luo. "Carbon Nanotubes Supported Pt Catalysts for Ethanol Oxidation in Alkaline Solutions." Advanced Materials Research 662 (February 2013): 132–35. http://dx.doi.org/10.4028/www.scientific.net/amr.662.132.

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An efficient method for functionalizing carbon nanotubes (CNTs) is reported, which combined HF corrosion with sulfuric acid and nitric acid for further oxidation. The X-ray diffraction and transmission electron microscopy are employed to investigate the physic-properties of the prepared catalysts. Cyclic voltammetry and chronoamperometry methods are used to study the performance of the prepared catalysts. CNTs further treated with H2SO4 and HNO3 mixed solutions with the volume ratio of 1 to 3, heating at 100 oC for 2 h, used as catalysts supports exhibit significantly improved performance towards ethanol oxidation in alkaline solutions in comparison with other decorated CNTs. The reason could be attributed to the oxygen-contain functional groups on CNTs surface can efficiently improve the interaction between CNTs and metallic particles in catalysts.

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Aileni, Raluca Maria, Laura Chiriac, Silvia Albici, Irina Mariana Sandulache, Valeria Neagu, and Liliana Raducu. "Multivariate analysis of the 3D composites based on nickel microparticles." Industria Textila 71, no. 05 (October 28, 2020): 446–51. http://dx.doi.org/10.35530/it.071.05.1772.

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This paper presents multivariate analyses of the experimental parameters obtained in the scientific experiments on eight sample fabrics of 100% cotton with electrically conductive properties and electromagnetic achieved through traditional treatments such as padding with antistatic agents, and direct printing or scraping with a polymeric paste based on nickel (Ni). Textile printing was obtained using polymers such as polyethylene glycol (PEG), polyvinyl alcohol (PVA), polyacrylate, ammonium salt, carboxylic acid Copolymer polyester, and Ni microparticles. For the eight samples that have been analyzed, the morphology of the surfaces using SEM (scanning electron microscope) with magnification 2000–8000x and electronic magnification microscopy with 4x, assessed the resistance to wet rubbing and dry the resistance of the surface after treatment in the solution of alkaline and acid sweat. Also, the samples above referred have been analyzed by spectrophotometry to evaluate the transmittance, and reflectance of the electromagnetic waves. It can specify that after treatments in acid or alkaline sweat solutions, the resistance of the surface has decreased by 103–105. It has been observed that for samples treated with acid or alkaline sweat, the reflectance was increased in comparison with the reflectance obtained for the original samples. The multivariate analysis provided refers to the study of some physic-chemical and optical parameters, of the samples collected, such as thickness, pH, reflectance, and transmittance

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ROSSI, Davide, and Renata URUCI. "A multidisciplinary approach for the physic-chemical characterization of peloids to new perspectives in the development for “hydrothermal Developing Countries” using partecipatory methodology." Balneo and PRM Research Journal 12, no. 3 (September 1, 2021): 227–32. http://dx.doi.org/10.12680/balneo.2021.442.

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The Osservatorio Termale Permanente (OTP) operated from 1996 to 2014 in the Italian and international therapeutic thermalism field. The main aim of OTP was the development of a multidisciplinary approach for the characterization of the quality of peloids for cutaneous application and their maturation process using different qualitative and quantitative analytic techniques opening at the Integrated Analytical Approach in the field of therapeutic thermalism. The main innovation introduced by OTP were rheology and surface tensiometry applications on peloids. The introduction of surface tensiometry included the skin as a fundamental element for the development of mud therapy protocols based on the bioadhesive properties of peloids. The interfacial investigations between peloids and skin led to the characterization of the exchange activity occurring during pelotherapy on the cutaneous surface in a non-invasive and fast way. On these bases, our work linked each other the multidisciplinarity approach to the study of hydrothermal resources performed by OTP with the concept of the participative methodology commonly applied to the development of projects in the field of development cooperation. This combined approach led us to develop a scientific proposal for the development of therapeutic thermalism in countries not yet improved in this field and characterized by the presence of hydrothermal resources. Keywords: peloid, surface tensiometry, Rossi factor, rheology, Rheological Termal Mud, skin, integrated analytical approach, participative methodology, therapeutical thermal proposal, hydrothermal development countries

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Jwanan Luther Emmanuel, Mustapha Omenesa Idris, Abdulmutalib Omeiza Usman, Quasim Musa, Abdulrahman Itopa Suleiman, and Ponfa Sambo. "Biomass-Derived Activated Carbon: A Viable Material for Remediation of pb2+ and 2, 4-Dichlorophenol (2, 4 DCP) through Adsorption." Journal of Advanced Research in Applied Sciences and Engineering Technology 25, no. 1 (December 19, 2021): 37–45. http://dx.doi.org/10.37934/araset.25.1.3745.

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Carbon has been one of the magnificent elements which have revolutionized material science. From carbon we obtain the best porous absorber (activated carbon) with excellent properties for large spectrum of industrial applications. Activated Carbon (AC) is the common term used for a group of absorbing substances of crystalline form, having a large internal pore structures that make the carbon more absorbent. This paper presents the surface properties of coconut shell derived-activated carbon and its sorptive applications. Some of the physic-chemical properties of the carbon were characterized in terms of porosity having value of 0.13, iodine number of 334.23 mg/g, surface area of 327.52 m2/g and surface acidity value of 0.31 mmol H+/g. The coconut shell activated carbon was subjected to various treatment conditions of (40oC, 60oC, 80oC) temperatures, (30 minutes, 1 hour, 2 hours) treatment time and (1 M, 2 M, 3 M) concentrations of HNO3. Surface acidity was determined on each of the treated activated carbon to establish the optimum condition of the acidic treatment. The highest surface acidity value of 3.06 mmol H+/g was obtained at treatment condition of 80oC, 2 hours and using 3 M concentration of the acid while the lowest value of 0.89 mmol H+/g occurs at 40oC, 2 hours and 1 M concentration. The adsorbent with the highest surface acidity was used to check the effect of the acidic treatment on the absorption of lead Pb and 2,4-Dichlorophenol (2,4-DCP).

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Sangve, Kiran. "Studies on planktonic diversity in fresh water reservoirs around Amravati district, Maharashtra." Environment Conservation Journal 21, no. 3 (December 17, 2020): 137–42. http://dx.doi.org/10.36953/ecj.2020.21316.

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The present study was carried out to assess the planktonic diversity and seasonal variations in the physic-chemical characteristics of Pohra, Wadali and Chhatri surface water reservoirs around Amravati during June 2014 to May 2015. During the course of study the zooplankton in the reservoir under investigation is represented by five major groups i.e. Ostracoda, Rotifera, Cladocera, Protozoa and Copepoda. Among phytoplankton a total of 28 algal species were recorded from all the reservoirs under study with 14 taxa from Chlorophyceae, 9 taxa from Bacillariophyceae and 8 from Cyanophyceae. The Chhatri reservoir was found to contain most of the pollution indicator species. Wadali reservoir also exhibited few pollution tolerant species. The water in all the reservoirs was found to be eutrophic in the order of Pohra > Wadali > Chhatri.

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Sena, Cristyana P., Renata S. Silva, Luciana A. Junqueira, Daniel D. F. Perreira, Patricia M. Albuquerque, Ariane Mendonça Kluczkovski, Tatiane P. Souza, Edgar A. Sanches, Amr M. Bakry, and Pedro H. Campelo. "Ultrasound-Assisted Preparation of Brazil Nut Oil-in-Water Emulsions Stabilized by Arabic Gum." Journal of Food Engineering and Technology 8, no. 1 (June 15, 2019): 1–9. http://dx.doi.org/10.32732/jfet.2019.8.1.1.

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The objective of this work is to evaluate the stability of Brazil nut oil emulsions with gum Arabic using ultrasound-assisted homogenization. The emulsions were prepared in a completely randomized design varying the time (2 and 4 min) and the ultrasound power (30 and 40%). The physicochemical properties of the emulsions (pH, conductivity, turbidity, zeta potential, surface tension, rheology and optical microscopy) were evaluated after the homogenization process and 4 hours later. The results showed that more energetic homogenization processes (longer duration and higher ultrasound power) favored the physicochemical properties, keeping the emulsions more stable. Thus, Brazil nut oil emulsions prepared with ultrasound-assisted showed good physic-chemical characteristics that can guarantee good emulsion stability during spray drying, guaranteeing efficiency and protection of the physical and chemical properties of the Brazil nut oil.

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Ahmad Saupi, Siti Rumaisha, Nur Ain Haris Abdul Haris, Mohamad Najmi Masri, Muhammad Azwadi Sulaiman, Bashree Abu Bakar, Mohd Hazim Mohamad Amini, Mazlan Mohamed, and Nik Alnur Auli Nik Yusuf. "Effects of Soil Physical Properties to the Corrosion of Underground Pipelines." Materials Science Forum 840 (January 2016): 309–14. http://dx.doi.org/10.4028/www.scientific.net/msf.840.309.

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Corrosion of metals in soil be able to change from comparatively fast material loss to insignificant effects, depending on soil environment. Corrosion is a process of deterioration of metal surfaces degraded into another compound. Soil is one of the medium known to have constituted to corrosion of metals. The soil creates an environment for the corrosion to react. The buried pipelines are exposed to the soil that may experience corrosion attack. The study of the soil as corrosion environment is important to mitigate the problem due to the environment and economy. There are factors that contribute to the corrosion process. This study concentrates on corrosion properties that expose to soil environment particularly underground pipelines. The mild steel coupons taken from actual pipelines, stimulating and analyzing the physic-chemical characteristics of the soil environment. The soil is sandy clay in natural. A total summed index of 2 numerical scale, thus, indicates that the soil tested was mildly to non-corrosive. The corrosion rate increase with increasing of moisture content and pH value. The observations on the coupon surface also did in order to study the morphology.

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Journal articles on the topic 'Surface physic'

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