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The widely use of petroleum-derived mineral oils for the production of offset printing inks has resulted in several environmental impacts. The suitable approach to develop alternative resources is palm oil fatty acid methyl ester (FAME) as a substitute for petroleum-based solvent. This study aimed to investigate the surface properties of palm oil-based offset ink on gloss-coated paper surfaces in terms of printability. The "green" varnishes were prepared with palm oil FAME as solvent, rosin-modified phenolic resin, and different vegetable oils linseed oil (FAME-LO) and soybean oil (FAME-SO) have been used as drying oils. The FAME-based Cyan offset printing inks have been prepared their properties compared with standard conventional inks. Printing tests were carried out using the IGT-A2 printability tester. Contact angles of water, methanol, and hexane on the surface of printed ink were measured using Contact Angle Analyzer. The surface free energy (SFE) and its components were calculated using Girifalco-Good-Fowkes-Young, Owens-Wendt, and van Oss-Chaudhury-Good methods. The results showed that as the liquid contact angle increased, the surface energy decreased. The surface energy of FAME-SO ink printed samples 36.36 mJ/m2 was higher than the unprinted paper 35.84 mJ/m2. Since high surface energy will affect the bond strength of the ink to the substrate, this will be an advantage for multicolor prints requiring good ink adhesion, which will enlarge the acceptance of other colors to be printed on the previous color. [ABSTRACT FROM AUTHOR]

The paper presents the results of a study on the creation of a silicon coating on a polyimide track (nuclear) membrane. The silicon coating was deposited by vacuum magnetron sputtering. The resulting coating was studied by scanning electron microscopy, as well as by X-ray phase analysis. The thickness of the applied ceramic coating on polyimide track membranes is 510 nm. It has been established that the deposition of a silicon coating significantly increases the hydrophilicity of the track membrane. There is a decrease in the contact angle of wetting with distilled water by 27.63%: from 60.91+6.63° to 50.59+7.42°. When measuring the wetting angle of the membrane surface with diiodomethane, the opposite situation is observed - the wetting angle of the membrane surface with diiodomethane decreases by 23.9%: from 40.83±3.96° to 50.59±7.42°. The deposition of a silicon coating on the membrane leads to an increase in the value of the surface energy by 14.36%, and the ratio between the dispersed and polar components changes significantly. Before spraying, the value of the dispersed component of the membrane was 15.85% of the total surface energy, after spraying it increases to 41.32%. [ABSTRACT FROM AUTHOR]

Polydimethylsiloxane (PDMS) is mostly used as a substrate for printing flexible electronic devices. Surface energy mismatch between the conductive material and PDMS and its hydrophobic nature limits the adhesion of the conductive material to its surface. Surface modification using oxygen plasma treatment is a quick and simple technique to convert a hydrophobic surface into a hydrophilic surface that matches the surface energy of the substrate and the ink, forming uniform printed conductive tracks. Plasma treatment parameters i.e., pressure, power, and time play an important role in determining the effectiveness of the treatment. The effectiveness of the treatment can be evaluated by measuring the contact angle and the diameter of the droplet. Thus, to optimize this parameter a two-level three-factor (23) factorial design of the experimental study was conducted and the variation in the response was analyzed using box plots. The objective was to minimize the contact angle and maximize the droplet diameter. PDMS was treated using these parameters and conductive silver tracks were inkjet-printed. The effectiveness of these treatment parameters was verified by multiple adhesion tests. Results revealed a small change (∼0.015µm) in thickness after the adhesion test. Thus, optimum plasma treatment parameters for printing flexible electronics on PDMS were determined. [ABSTRACT FROM AUTHOR]

Water consumption of concentrating solar power plants for mirror washing is an area of concern from a financial, environmental, and humanitarian perspective, and much effort is being undertaken to reduce this facet of water use. Presented here is a novel plasma generating device that enhances conventional water washing by modifying the surface energy of the mirror samples to produce a hydrophilic surface that more evenly distributes water over the mirror surface. Hybrid plasma washing achieved higher values of reflectance (95.5%) than water washing alone (93.2%), and exhibited an anti-soiling effect when subject to further soiling (78.5% and 75.3% respectively). [ABSTRACT FROM AUTHOR]

Catalyst is an agent that enhances the reaction rate without itself being altered. It plays a major role in chemistry to ease the reaction and to obtain the products in maximum yield. Green chemistry utilizing green catalysts can be applied to nano catalyst and organic catalyst. Nanocatalysts with high activity, selectivity, durability, and recoverability are essential for enabling a broad range of potential developments and contribute to the resolution of current environmental, social, and industrial challenges. Catalytic performance of nano catalysts is enhanced due to the presence of support for nano materials increased specific surface area and increased surface energy. Organocatalysts are chiral or achiral organic molecules of low molecular weight, constituted by carbon, hydrogen, nitrogen, sulphur and phosphorus which catalyzes a reaction in sub stochiometric amounts. This review focuses on the role of nano catalysts and organic catalysts as green catalysts, their mechanism and applications in the synthesis of benzimidazole analogues. [ABSTRACT FROM AUTHOR]

Nanotechnology is regarded as the most important technologyin the twenty-first era. Nanomaterials are artificial materials having size of 100 nm (1nm=10−9 m) with specific qualities and functionalities. The growing utilisation of synthetic nanomaterials has broadened the breadth of their applications in a variety of disciplines. Nanomaterials uses in fields like medical investigations, product manipulation, pollutant degradation, and bioengineering are rising as nanotechnology becomes more industrialised. Nano catalysts have a higher specific surface area as well as surface energy, resulting with high catalytic performance. By allowing processes to proceedat a low temp, minimizing the risk of negative effects, increasing recyclability, as well as recovering energy, we can reduce the amount of energy used, the employment of a nano-catalyst improves reaction sensitivity. Here this review is highlight on use of nanomaterial catalyst for the synthesising indoles and showing the applications over other chemical catalysts or also highlight their mechanism of nanocatalysts. [ABSTRACT FROM AUTHOR]

The surface urban heat island (SUHI) is a significant human change of the earth's surface that can affect the local thermal climate by affecting surface energy flow at the surface. This study aimed to evaluate diurnal and seasonal variations of surface urban heat islands (SUHI) for study areas (Erbil & Baghdad) using LST values obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) Satellite. SUHI intensity calculates the difference between LST between urban and rural areas. Two months (January as winter days and July as summer days) use for seasonal variations and daytime and nighttime for diurnal variations. The study results show that, generally, LST values were higher in summer than in winter, during the day and at night for both cities. As for SUHI intensity, the highest value was in the summer of Baghdad, when it was (7.2°C -7.1°C). [ABSTRACT FROM AUTHOR]

The energy state of the surface plays a decisive role in the fundamental physical processes of adsorption, the migration of adsorbed particles along the surface, and the chemical interaction of particles near the separation of two phases. The paper presents the results of studies of free surface energy and its components (polar and dispersed) for thermally modified wood. The sequences of polarity change and their ratio with the main component of plant material after surface treatment with a protective coating, which are consistent with the structural and functional features of thermally modified wood. Thus, plasticizing and stabilizing substances that reduce surface tension can be adsorbed on the surface of the material, and therefore the amount of adsorption is determined by the free surface size, concentration, temperature and nature of the adsorbent and adsorbent, and the higher the concentration of the substance, the greater the adsorption. [ABSTRACT FROM AUTHOR]

In film composites, different plastics are combined to achieve complex property profiles in the product. One challenge that arises is the generation of sufficient adhesion between the bonding partners. The surface energy of the respective plastics is considered as a decisive parameter. For a bond at the interface, the surface energy should be as high as possible and consist of equal polar and disperse fractions. However, the polarity or surface energy of plastics differs due to the macromolecular structure. If the difference is too great, a composite is not necessarily possible. To overcome these differences adhesives and adhesion agents are used in practice, which are often associated with disadvantages (i. e., an additional process step). Moreover, there are increasing requirements due to new legal restrictions for the application of raw materials used in the adhesion agents and adhesives. This paper suggests a new approach to overcome these deficits by treating the partner with the lower surface energy in molten form with atmospheric pressure plasma to create a film composite, which is free of adhesion agents and adhesives. In this context, investigations on the plasma treatment of plastic melts were carried out. The target value for the assessment was the surface energy, considering the polar and disperse fractions. Contact angle measurements showed a significant increase in surface energy of the plastic which was treated with plasma. Subsequently, it was investigated whether the treatment of plastic melts can be used for an adhesive-free film composite. [ABSTRACT FROM AUTHOR]

Land Surface Temperature (LST) is an essential climate parameter, related to surface energy balance. The main objective of the present study is to use remote sensing and Geographical Information System (GIS) to calculate the land surface temperature of the Al-Ubaydh Basin, South of Anbar governorate in Iraq. Split Window (SW) algorithms were applied on the Landsat-8 infrared thermal band to calculate surface temperature. The results showed that the LST in the study area ranges between 20.4 to 46.2 degrees Celsius in October 2020, compared to 25.7 to 63.7 degrees Celsius in June of the same year, both captured at 10:45 am. These results indicate that the land surface temperature (LST) decreases in the eastern and western regions of the study area as well as towards the center due to agricultural sectors and land/rock composition respectively. The generated LST map is generally compatible with previous studies that base on radiometers or a thermal terrestrial camera that provides direct measurements. Thus, this study has demonstrated the capabilities of remote sensing as an effective, low-cost, and affordable tool that can be used to obtain LST. [ABSTRACT FROM AUTHOR]

There have been review about modifications of metal oxides synthesis, characterization, and applications over the last 10 years approximately 35000 journals from Sciencedirect.com as data sources for metal oxide synthesis as photocatalysts. From a search engine of 35,000 journals discussing this matter, the filtering process in specific areas involved green and chemical environmental methods with the results of about 145 journals. Then a specific assessment was carried out that referred to natural molecular and non-toxic processes and improved the photocatalytic properties of the oxide to produce 19 comprehensively reviewed journals. The aim of this metal is to determine the potential of plant extracts or natural sources as support system agents in the synthesis of oxides from previously published journals by researchers. The properties of (solid) nanomaterials for photocatalyst applications from the last 10 years trend to produce catalysts with relatively good physical, electronic or chemical characteristics compared to previous strategies in semiconductor production. This study is not only a wider field of view in the development of the discovery of metal oxide nanoparticle catalysts but also useful for increasing the efficiency of photocatalysts for various applications in organic waste treatment. Modifications on the surface can be carried out using nature-based methods with the aim of improving various surface characteristics involving surface energy, and reactivity as well as charge kinetics, active sites, biocompatibility, and hydrophilicity to control physicochemical developments in photocatalysis. Keyword: metal oxide, synthesis, photocatalysts, green method [ABSTRACT FROM AUTHOR]

This article examines three generations of solar cells. On the basis of the proposed model, the anisotropy of the thickness of the surface layer and the surface energy of single-crystal silicon, amorphous silicon, crystalline films of cadmium telluride, copper-indium diselenide, gallium arsenide, indium phosphide, and lead-halide perovskite are calculated. Some of the elements represented a cubic structure, and some - a tetragonal structure. The thickness of the surface layer is a nanostructure, which is determined by one fundamental parameter - the atomic volume of the compound. It is shown that solar cells for cubic crystals should be selected with the (100) face, where the smallest thickness of the surface layer is observed, and for tetragonal crystals with the a but not c face. A small amount of surface energy corresponds to solar cells with a high conversion efficiency of sunlight. [ABSTRACT FROM AUTHOR]

The bimetallic samples were produced by wire-feed electron beam additive manufacturing. Layer-by-layer and drip methods were chosen for the production of bimetal. The features of the methods in the distribution of dissimilar materials on the surface of the longitudinal section are revealed on the vertical walls. So, in the longitudinal section of the sample produced according to the layer-by-layer method, there is a homogeneous distribution of dissimilar metals over the entire surface. In the longitudinal section of the sample, produced according to the drip method, there is a pronounced inhomogeneous distribution of dissimilar materials, with a predominant accumulation of steel. The presence of large (up to 6 mm) "drops" of steel and inhomogeneous distribution has a negative impact. The inhomogeneous distribution of the material in this case leads to an increase in surface energy. In turn, this leads to an increase in the deformation energy, and, consequently, the energy of the crack surface formation. [ABSTRACT FROM AUTHOR]

Using the concepts of the adsorption theory of interaction between solid and liquid phases, a thermodynamic analysis of the conditions of the nucleating model of the phaseifier particles is carried out. It is shown that modification with refractory particles consists not only in the introduction of particles into the liquid metal, but also in the formation of a transition layer on the surface of the particles, which ensures the stability of the process. It is analytically established that the process of heterogeneous nucleation and growth of a solid phase from a liquid phase is described by the thermal, surface and chemical state of the system and is characterized by three parameters: supercooling of the melt at the crystallization front, free surface energy at the interface, and an increase in the chemical potential of the components during the phase transition. It has been established that crystallization will occur on the impurity that has the largest chemical potential difference and the smallest surface energy in a given liquid. Therefore, it is advisable to use, along with refractory insoluble particles, soluble additives (protectors) that reduce the amount of surface energy. The performed analysis of the thermodynamic conditions for the stability of the process of heterogeneous nucleation and growth of phases made it possible to outline a real way of intensifying the process of heterogeneous nucleation - complex modification. [ABSTRACT FROM AUTHOR]

This paper presents the study of DBD generated at a pressure of 40 Torr in a parallel plate electrode system. The main objective of the study was to obtain a stable and homogeneous DBD for uniform treatment of materials. The discharge operating at line frequency (50 Hz), voltage 13kV (rms) and pressure 40 Torr was used to improve the wetting properties of polypropylene (PP). The changes in the surface hydrophilicity were investigated by contact angle and surface free energy measurements. The polymer surface morphology and roughness before and after the DBD treatment were analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The PP films modified by plasma treatments show a remarkable decrease in the water contact angle indicating the consequent increase in surface energy. This can be attributed to the introduction of oxygen-containing groups on the surface and the etching of the surface. [ABSTRACT FROM AUTHOR]

Multiferroic nanocomposite is recognized as one class of multiferroic with high magnetoelectric coefficient offered by their excellent magnetic-electric coupling via strain interaction. The strain interaction or structural coupling in this system is very important, which is, it can be tuned further by modifying the nanocomposite architectures. Here, we conduct a comparative study of the multiferroic nanocomposite BiFeO3 (BFO)-CoFe2O4 (CFO)/SrTiO3 (STO) with various vertically aligned nanocomposite architectures. It appears that both of BFO and CFO phases can be formed as a matrix and/or a pillars or vice versa depending on the crystalline orientation of STO substrate. The formation of matrix- pillars are strongly influenced by surface energy anisotropy between constituent BFO and CFO phases. [ABSTRACT FROM AUTHOR]

Investigations of the elemental composition and wettability of polylactic acid obtained by electrospinning and modified by argon and oxygen low-temperature atmospheric pressure barrier discharge plasma are described. X-ray photoelectron spectroscopy analysis indicates that the destruction and oxidation processes of polymer bonds occur simultaneously after plasma modification. It was established that enhancement of carbon bonds leads to the surface carbonization. Plasma modification contributes to the polylactic acid surface energy increasing. [ABSTRACT FROM AUTHOR]

The purpose of this research is the study the influence of the plasma modification on PCL films properties and the influence PCL films implantation on the morphology of the cornea in vivo experiment. The feedstock for films was obtained by dissolving PCL in the chloroform. Modification of the films was carried out using the low-temperature plasma. Studies were performed on 4 pubescent female Sylvilagus bachmani rabbits. The PCL films were implanted into the cornea of one animal eye. Sampling (animal's eyes) was performed on day 21 after the start of the in vivo experiment for morphology studying. Results showed that the plasma modification increases a roughness (1.5 times) of PCL films, the hydrophilicity of films, reducing the contact angle of the inner side by 9°–10° (12%–14%), and increases the surface energy values mainly due to the polar component to 20.6±0.3 mJ/m2. The implantation of the PLA films contributes to the development of the inflammatory response as a result of the surgery and implantation of the polymer material. The study showed the possibility of the plasma-modified PLA films using as a corneal implant in the future. [ABSTRACT FROM AUTHOR]

An innovative plasma technology is being developed, which is capable of cleaning Concentrating Solar Power (CSP) mirrors without the use of water. This novel technology also has additional benefits, which includes increasing the self-cleaning nature of the mirror surfaces and reducing surface soiling by modifying the surface energy of the collector mirrors. It is projected that this disruptive technology will save billions of litres of water per year, globally and will also increase the energy efficiency of the CSP power plants. [ABSTRACT FROM AUTHOR]

Self-cleaning application of metal oxide thin films has been the topic of research interest in the recent years. In this work surface wetting characterization of spray deposited Sr doped SnO2 thin films is presented. Strontium doped tin oxide films are polycrystalline with tetragonal structure having preferential growth along (1 0 1) and (2 1 1) planes. The films are uniform, crack-free and transparent in the visible region. The surface energy of SnO2:Sr thin films increases when the concentration of Sr increases up to 1wt% but decreases at 1.5wt% of doping. The spectroscopic ellipsometric data of SnO2:Sr was used to estimate variation of packing density in SnO2:Sr films. Packing density decreases with Sr concentration up to 1wt%, but increases at 1.5wt% of Sr. The contact angle measurements at different concentration of Sr indicate increase in the hydrophobicity of SnO2:Sr (1.5wt%) thin films. This property is ascribed to combined effect of variation in surface energy and packing density. The hydrophobicity of SnO2:Sr (1.5wt%) can be utilized in developing self-cleaning surfaces needed in the outdoor opto-electronic device installations as well as on windows of aircrafts and buildings. [ABSTRACT FROM AUTHOR]

Biocomposites made of biodegradable polymers have grown in interest due to their environmentally friendliness, considering that non-biodegradable polymers waste conduces to pollution, displaying high environmental impact in climatic changes. Therefore, in the presented study, biodegradable Poly (lactic acid) (PLA) and poly (butylene succinate) (PBS) were investigated as a series of PLA/PBS melt-blending compounds with the weight ratios of 50/50, 60/40, 70/30, 80/20 and 90/10. In a two-component injection molding process, they were used as the hard component to create hard-soft-combinations. Thermal properties, crystallinity and mechanical properties were examined with regard to the change in the adhesive bonding strength between the PLA/PBS compounds and thermoplastic polyurethane (TPU) under the influence of time and temperature (storage at room temperature and 100 °C in the course of 1, 3, 7 and 14 day(s)). The adhesion properties of the PLA/PBS blends were identified via Drop Shape Analysis (DSA) using a contact angle measurement device and corroborated with FTIR/ATR measurements. The attenuation in the interfacial tension between the blends and TPU with increasing amount of PBS content in the blend provided better bonding abilities. The maximal load required to disconnect these two components was measured by a universal tensile test machine. According to the results, the highest maximal load (552,69 N) was achieved with the PLA/PBS blend with a weight ratio of 60/40 wt% after being subjected to seven days of storage at 100 °C. [ABSTRACT FROM AUTHOR]

Plasma treatment of polymeric materials is a promising method of modifying surface properties. In particular, under the influence of gas plasma, the polymer structure is changed and a carbonized surface layer is formed, which affects the surface energy, relief texture and other surface properties. In this way, biomedical characteristics (sorption of proteins, decrease of bacterial adhesion) could be improved. However, external mechanical loads associated with the use of soft polymers can cause damage of the modified surface. These defects reduce the positive effect of plasma treatment. In this paper, the influence of low-energy plasma implantation of nitrogen ions (energies 0.1 and 0.5 keV) on the surface properties of elastic polyurethane is investigated. As a result of the treatment, the hydrophobicity and surface stiffness increase. However, in comparison with the higher plasma energy (at least 1 keV), the damage of the stretched material surface does not occur. [ABSTRACT FROM AUTHOR]

The influence of the electret on the properties of cartonboard modified with amylose or polylactide is shown. It was revealed that the application of the polylactide coating leads to a change in the surface properties of the paperboard to the side of hydrophobization, and to the starch coating to the side of hydrophilization. The effect of the unipolar corona discharge on modified cardboards leads to the decrease in their free surface energy by 20–25%. [ABSTRACT FROM AUTHOR]

A thermodynamic analysis of oxidation of copper nanoparticles was performed. The first step of oxidation, namely Cu2O formation on the surface of spherical copper particles (core-shell model) was considered. Our results show a spontaneous oxidation of particles at oxygen pressures well below the equilibrium oxygen pressure in bulk system and a stability of oxide shell up to higher temperatures. This surface related effect result from a negative surface contribution to the Gibbs energy of the reaction 4 Cu(s) + O2(g) = 2 Cu2O due to the higher surface energy of solid copper compared to the surface energy of Cu2O and interfacial energy on the Cu/Cu2O interface. [ABSTRACT FROM AUTHOR]

The paper presents the results study of the morphology, elemental composition and wettability of the Ti-Ni-Nb surface alloy formed by the additive melting of Ti-Nb coating with TiNi substrate by electron beam. It was found that the topography of samples with a Ti-Ni-Nb surface alloy is inherited from the samples after electron-beam treatment in the melting mode, which precedes the deposition of coatings. The distribution of titanium, nickel and niobium on the samples surface is uniform, with the exception of single areas containing microcraters, which are formed at the stage of preliminary LEHCEB treatment. The composition of the surface alloy is Ti50Ni27Nb20 (at %). The oxygen concentration of the samples is at the limit of detection and is 3 at %. It was established that the samples surface is hydrophobic. The value of the surface free energy is σ = 26.82 ± 0.9 mN/m, while the contribution of polar component 4%. [ABSTRACT FROM AUTHOR]

This paper reports the results of studies of the surface free energy of TiNi alloy after ion beam treatment and its influence on the proliferative activity of mesenchymal stem cells of rat bone marrow. It has been established that a decisive influence on the free energy and distribution of its components is realized by the phase composition of the oxide layer, which forms on the surface of TiNi samples after ion beam treatment and depends on the type of implanted ion. It was found that, despite the surface of modified samples having a relatively low free energy, the predominance of the polar component of surface energy increases the proliferative activity of cells cultivated on these samples. [ABSTRACT FROM AUTHOR]

The paper is devoted to the study of the properties of silicides used as high-temperature materials of various designs. The surface energy and the thickness of the surface layer of atomically smooth metal silicides were investigated. To determine the surface energy, the dependence of the luminescence of metal silicide on the grain size of the phosphor was used. It was established that for binary silicides of a number of transition and rare-earth elements, the magnitude of the surface energy is in the range from 1 to 2 J/m². It is shown that the calculated thickness of the surface layer d(I) does not exceed 3-6 nm (with the exception of four silicides). When the layer thickness exceeds d, a structural phase transition occurs. When the layer thickness d (II) ≈ 10d, size effects characteristic of nanostructures begin to appear. Classically as nanostructures are called objects which dimensions in one direction do not exceed 100 nm. Nanostructures classically are objects whiche dimensions in one direction do not exceed 100 nm. It has been established that for Cr5Si3 → V5Si3 → Ti5Si3 → Nb5Si3 silicides, the d(II) layer has dimensions from 106 to 131 nm, where size effects are detected. These silicides possess extraordinary physicomechanical properties and demonstrate a great potential of using them as heightemperature light materials for turbine blades, heat-shielding plates for combustion chambers and rocket nozzles. [ABSTRACT FROM AUTHOR]

Novel material solutions for bipolar plates in fuel cells require adapted ways of joining and sealing technologies. Safe and life time enduring leak-tight contacts must be achieved by automatic processes using reasonable joint forces. A proper sealing should manage such challenges as good ageing properties, excellent leak-tightness, high thermal conductivity and low gas permeability. Hence in this work, adhesive bonding and welding are considered as suitable methods, which can fulfill the requirements mentioned above. Adhesive systems seem to be more easy to apply than conventional sealing (hand layed-up rubber gaskets), e.g. with automatic dispensers. Additionally, the properties of an adhesive joint can be enhanced by a process-specific surface pre-treatment. This work focuses on the characterization of adhesive systems and their joints with highly filled graphite composites. Mechanical properties of the joints were characterized through lap-shear tests. The influence of ageing caused by humidity or acidic solvent at increased temperature on the bond line properties as well as neat adhesive was examined. The thermal conductivities of neat adhesives and through the entire joint were examined. In order to improve above conductivities, roughening, substrate pre-heating, post-curing and various contact pressure weights were applied. Plasma treatment was chosen as surface pre-treatment method for improving substrate’s surface energy. An alternative to bonding is plastic welding, which does not require the use of sealants and adhesives. Based on former study of influences of filler content on the welding process using ultrasonic, hot plate or infrared welding, a welding method for joining the graphite compounds was derived. [ABSTRACT FROM AUTHOR]

The superhydrophobic surface of the AMG-6 aluminum alloy was obtained by laser radiation and heating in a muffle furnace processing. The fluid volume and interval after dosing for recording the geometric characteristics of a drop by the sessile drop method were selected to determine the free surface energy (SFE) and adhesion with liquids. The effect of molecules reorientation of the treated metal surface layer after wetting with water has been established. Adhesion with lubricants and heat carriers has been determined. It has been established that laser processing of aluminum alloy can significantly reduce adhesion forces. [ABSTRACT FROM AUTHOR]

The free surface energy (SFE) of aluminum alloy treated by laser radiation was determined by the OWRK method taking into account the surface roughness. The divergence of the SFE calculated with and without roughness was established. Nomograms for evaluating wetting characteristics of surfaces treated by laser radiation were obtained. That can be used to predict wetting and adhesion with liquids of different composition. [ABSTRACT FROM AUTHOR]

The study of wetting properties and surface free energy (SFE) of granodiorite, dolomite and recycled ceramic aggregate was presented in the paper. Every tested aggregate had different wetting properties. Based on the SEM study, the microstructure was shown. Wetting properties of various aggregates were determined by measuring the contact angle of their surface using water as measuring liquid. Many factors influence the contact angle, including physical and chemical homogeneity, roughness and surface contamination, type of measuring liquid, drop size of measuring liquid, humidity, ambient temperature, etc. Measurements were carried out 0 minutes after the time of application of the drops. The total SFE was determined using the Neumann method. Analyzing examination results it can be noticed that the values of contact angles depends on the absorbability of aggregate and smoothness of its surface. The results of contact angle measurements proved that all contact angles for ceramic aggregate were lower than contact angles for dolomite and granodiorite. That causes the total SFE for ceramic aggregate was higher than SFE for dolomite and granodiorite aggregate. The highest contact angle was noticed for granodiorite. The smallest contact angle with water was obtained by ceramic aggregate. This is due to physical characteristics of this aggregate. Ceramic aggregate is characteristic of the high absorbability. This indicates an increased wettability and increased adhesion properties. [ABSTRACT FROM AUTHOR]

The high usage of energy in manufacturing sector can lead to significant impact to environment and sustainability. Various strategies have been done in order to minimize energy consumption in manufacturing. The reduction of energy during the machining process is one of the initiatives to achieve sustainable machining. Thus, this research was done to investigate the influence of CNC milling parameter for minimum energy consumption. The parameter involves are spindle speed (N), feed rate (Vf) and depth of cut (d) while the output is power and energy usage. The cutting tool of high-speed steel (HSS) was used to cut the aluminium (Al6061) alloy using 5-axis CNC milling machine. The design of experiment (DOE) approach was applied by using response surface methodology (RSM) to optimize the experimental work. Then, the analysis of RSM determines the influence of machining parameter toward energy consumption. The surface plot of energy interaction for each milling parameter was generated using RSM. From the study, it is found that the feed rate is the most influential factor for lower energy machining of milling operation. In addition, the RSM also proposes the regression model to show a relationship between energy and machining parameter which the accuracy of 98%. [ABSTRACT FROM AUTHOR]

With the use of numerical simulation, thermophysical processes are considered when modifying the surface layer of a metal in a moving substrate. The material is heated and melted under the influence of a continuous induction high-frequency electromagnetic field on the substrate surface through a rectangular region. The distribution of electromagnetic energy on the surface of the substrate is uniform, and within it is described by empirical formulas. It is assumed that nanoscale particles of the refractory compound penetrate, evenly distributed, into the melt during melting of the metal and act as active centers of crystallization. The boundary of the melting range is determined in the Stefan approximation, and the boundaries of the solid phase growth region are within the framework of Kolmogorov's theory of the crystallization of metals. Based on the results of calculations, the temperature field distribution, the size of the melting and crystallization zones, and the growth kinetics of the solid phase are estimated in the quasi-stationary approximation. The characteristics of induction heating have been determined, which make it possible to shorten the surface treatment time. The values of the specific power are obtained depending on the speed of the substrate in the range 1-3 cm/s, which make it possible to preserve the dimensions of the melting and modifying region unchanged. [ABSTRACT FROM AUTHOR]

Membrane distillation (MD) is an attractive separation process since it can be used to recover water with nearly 100 % non-volatile rejection. MD is also considered to be environmentally friendly since the waste heat at low temperature or the solar energy heat can be used for the separation. Despite of having these great features, MD has not been widely used for commercial purpose up to date. The hindrance factors include the lack of commercially available membrane that tailored for MD, the low permeation flux as well as operational issues especially membrane wetting and fouling. In this work, polyvinylidene fluoride (PVDF) membranes incorporated with TiO2 nanoparticles were modified using hydrophobic silane to enhance the permeate flux and to reduce membrane wetting. The polymer loading was varied in the range of 13 – 16 wt% to form thin membranes on woven support via dual bath coagulation. This coagulation technique produced membranes with spongy structure and rough surface. The dry membrane was modified by using low surface energy silane, tridecafluro-1,1,2,2-tetrahydrooctyl triethoxysilane. TiO2 nanoparticles embedded on membranes provided the active site for silane modification process. All the membranes possess superhydrophobic surface with water contact angle beyond 160 °. The increment of polymer loading reduced the average pore size from 0.41±0.01 µm (13 wt%) to 0.34 ± 0.04 µm (16 wt%). Aside from that, the membrane porosity was reduced while membrane thickness was increased with the increasing polymer loading in dope solution. After 8 h of MD operation, the modified PVDF/TiO2 membrane with 13 wt% polymer loading in dope solution showed the highest permeation flux. The membrane with large pore size, high porosity, low thickness and great hydrophobicity is preferable in MD. [ABSTRACT FROM AUTHOR]

Superhydrophobic surfaces are widely used in various industrial and self-cleaning applications. Here, we present a low cost, facile synthesis of UV-resistant copper based superhydrophobic (SH) surface. The copper is electrochemically deposited on an another copper foil at the room temperature. The electrochemical bath consists of an aqueous solution of CuSO4 and H2SO4 acid. The samples were rinsed in ethanol and dried in a vacuum oven at 100 °C. The substrates were dip coated using 1 % Teflon AF solution to lower the surface energy. Also, another batch of copper surfaces was treated in stearic acid solution for hydrophobic coating. Both, the stearate and the Teflon coated copper surfaces shows hierarchical micro-nano surface morphology. The wetting properties on both the surfaces were extensively tested by static contact angle analysis, contact angle hysteresis (CAH) and droplet bouncing and rolling. Both the surfaces show, the average contact angle is about 165° and CAH is about 4°. The stability of the SH coating is tested against exposure to the ultraviolet (UV) A, B and C radiations. The Teflon AF coated surface retains SH property even after 2 hrs of UV exposure, whereas the stearate coating shows degradation in merely 30 min of exposure. Thus, the Teflon coated copper rough surface has potential in outdoor SH applications. [ABSTRACT FROM AUTHOR]

Herein, growth and characterization of spray deposited strontium doped zinc oxide thin films is presented. The structural analysis demonstrates that, thin films are polycrystalline with hexagonal wurtzite structure. The surface energy of ZnO:Sr (3%) thin films is decreased along c-axis. The optical dispersion analysis revealed the enhancement of packing density in ZnO:Sr films. The observed improvement in hydrophobicity of ZnO:Sr thin films is owing to collective effect of decreased surface energy and increased packing density. These dopant dependent variation in hydrophobicity of ZnO:Sr thin films is illustrative for self-cleaning driven applications. [ABSTRACT FROM AUTHOR]

A model of the surface energy balance based on the Force Restore method was developed. Parameterization and computational solutions were proposed for the albedo, thermodynamic equilibrium conditions of the atmosphere and improvement of the nudging of Force Restore method. Experiments were conducted to estimate atmospheric variables and energy flows on the surface, in the region of the City of Rio de Janeiro, and compared to simulations using the model. The results show that the model, with the suggested parameterization, had superior performance to what is being used in models of usual atmospheric prognosis. The mean standard error of the surface temperature was reduced from about 1.5 ° C to values around 0.5 ° C, in the diurnal cycle, taking as basis of comparison the data of the experiments. [ABSTRACT FROM AUTHOR]

The objective of this work was to investigate the best style of Langmuir isotherm model of Non-Competitive Sorption Zn(II) and Cd(II) on Horse Dung Humic Acid (HD-HA). The sorbent (HD-HA) was extracted by Stevenson's method and it was characterized by FT-IR, UV-Vis, and total of acidity. The sorbent was applied to sorbed Zn(II) and Cd(II) in optimum pH and separated container. The data was then analyze by four style of Langmuir isotherm model i.e. Langmuir-a, Langmuir-b, Langmuir-c, and Langmuir-d. The result of characterization study by FT-IR, UV-Vis, and content of acidity was the HD-HA has the very similar character with PS-HA. It was proved in this work by separation factor (RL) that all of the style was favorable, but the most used Langmuir style in some publication, Langmuir-a, have the best linearity in both Cd(II) and Zn(II) sorption. Selection of usage of these style has no significant difference to determine the sorption capacity (b), but it has broad values to equilibrium constant (KL) which in this study ranged 5651-10000 L/mole and 7929-11111 L/mole for Cd(II) and Zn(II), respectively. The best linearity of application the sorption in kinetics equation was follow pseudo-second order Ho kinetics equation. The relationship of RBS kinetics equation with Langmuir data was the value of K from ka/kd of RBS equation which was 3452 (L/mole) for Cd(II) and 10898 (L/mole) for Zn(II). The value of KL and K of Zn(II) sorption was neaRLy close and value of K from RBS kinetics equation is in the range of KL from different Langmuir style. The value of K of Cd(II) sorption was not so close and out of range of different style Langmuir data. [ABSTRACT FROM AUTHOR]

The microstructure of pentaerythritol tetranitrate (PETN) films fabricated by physical vapor deposition can be altered substantially by changing the surface energy of the substrate on which they are deposited. High substrate surface energies lead to higher density, strongly textured films, while low substrate surface energies lead to lower density, more randomly oriented films. We take advantage of this behavior to create aluminum-confined PETN films with different microstructures depending on whether a vapor-deposited aluminum layer is exposed to atmosphere prior to PETN deposition. Detonation velocities are measured as a function of both PETN and aluminum thickness at near-failure conditions to elucidate the effects of microstructure on detonation behavior. The differences in microstructure produce distinct changes in detonation velocity but do not have a significant effect on failure geometry when confinement thicknesses are above the minimum effectively infinite condition. [ABSTRACT FROM AUTHOR]

The effects of deformable free surface and uniformly internal heating on the arrival of marginal Marangoni convection in a horizontal binary fluid layer are considered theoretically using linear stability analysis. Both the lower and upper boundaries are assumed to be perfectly insulated to temperature perturbation. We used the regular perturbation method to obtain the critical solution for the resulting eigenvalues problem. We found that the coupling of deformable surface and internal heat parameter can hasten the onset of convection. [ABSTRACT FROM AUTHOR]

In engineering area, investigation of shape effect in elastic materials was very important. It can lead changing elasticity and surface energy, and also increase of crack propagation in the material. A two-dimensional mathematical model was developed to investigation of elasticity and surface energy in elastic material by Adaptive Finite Element Method. Besides that, behavior of crack propagation has observed for every those materials. The government equations were based on a phase field approach in crack propagation model that developed by Takaishi-Kimura. This research has varied four shape domains where physical properties of materials were same (Young’s modulus E = 70 GPa and Poisson’s ratio ν = 0.334). Investigation assumptions were; (1) homogeneous and isotropic material, (2) there was not initial cracking at t = 0, (3) initial displacement was zero [u1, u2] = 0) at initial condition (t = 0), and (4) length of time simulation t = 5 with interval Δt = 0.005. Mode I/II or mixed mode crack propagation has been used for the numerical investigation. Results of this studies were very good and accurate to show changing energy and behavior of crack propagation. In the future time, this research can be developed to complex phenomena and domain. Furthermore, shape optimization can be investigation by the model. [ABSTRACT FROM AUTHOR]

The increase of optical absorption efficiency of Si (100) surface by 7 keV and 8 keV N+ ions bombardment has been reported here. A periodic ripple pattern on surface has been observed as well as silicon nitride is formed at the ion impact zones by these low energy N+ ion bombardment [P. Karmakar et al., J. Appl. Phys. 120, 025301 (2016)]. The light absorption efficiency increases due to the presence of silicon nitride compound as well as surface nanopatterns. The Atomic Force Microscopy (AFM) study shows the formation of periodic ripple pattern and increase of surface roughness with N+ ion energy. The enhancement of optical absorption by the ion bombarded Si, compared to the bare Si have been measured by UV – visible spectrophotometer. [ABSTRACT FROM AUTHOR]

Adsorption of small gas molecules (such as CO and O2) on pristine graphene (PG) and Li-adsorbed graphene (PG-Li) have been investigated using first principles methods within density functional theory (DFT). We also notice that PG-Li has a higher chemical reactivity towards the gas molecules as compared to PG and these molecules have higher adsorption energy on this surface. Moreover, the strong interactions between PG-Li and the adsorbed molecules (as compared to PG and gas molecules) induce dramatic changes to the electronic properties of PG adsorbed with Li and make PG-Li a promising candidate as sensing material for CO and O2 gases. [ABSTRACT FROM AUTHOR]

In this research, we develop a method to simulate nonsymmetric triple junction motion given by the gradient flow of surface energy with arbitrary surface tensions of the participating interfaces. The foundation of the method is the diffusion-based BMO algorithm in vector-valued formulation. We realize the nonsymmetric motion by generalizing the original BMO method and adding a corrective projection step. In the end, we show the numerical example for the simulation of the bubble motion using two different contact angles to simulate the contact angle dynamics. [ABSTRACT FROM AUTHOR]

This study aims to establish a numerical strategy allowing to take into account the capillary and wetting issues, considered on the macroscopic scale as a discontinuity of pressure at the fluid-gas interface, and surface tension force balance at the local scale. This modelling is based on the Brinkman/Darcy and Stokes equations solved by a finite element stabilized method. Specific numerical methods are implemented to deal with the discontinuity of pressure field across the flow front. One of the challenges lies in modelling across scales capillary force effects in infusion-based processes to scale-up rules for flows at the process scale, because the computation cost of numerical simulations at local scales is too not tractable industrially. [ABSTRACT FROM AUTHOR]

It is established that coating irradiation by electron beam leads to coating structure dispersion, to microhardness increase and to friction coefficient decrease. The surface energy is enlarged too. That leads to wear resistance growth. The obtained operational characteristics results for ion-plasma multi-element coatings show their usage expediency for the equipment hardening which is applied in the oil production and refining systems. [ABSTRACT FROM AUTHOR]

A significant three-month lag correlation between June top-of-atmosphere reflected solar radiation (RSR) and the subsequent September sea-ice extent (SIE) is found within the Arctic, and the predictability of September SIE is examined by both satellite observations and reanalysis datasets. The correlation coefficient between de-trended June RSR and September SIE reaches up to 0.88 for MISR, and the forecast skill of 0.36 using MERRA-2 reanalysis dataset is similar to or better than complex prediction models. Results confirm the particular importance of the early summer surface energy budget and help to explain the abrupt declines of September SIE in the past decade (2007, 2012, 2015). [ABSTRACT FROM AUTHOR]

Arctic low clouds strongly affect the Arctic surface energy budget. Through this impact Arctic low clouds influence important aspects of the Arctic climate system, namely surface and atmospheric temperature, sea ice extent and thickness, and atmospheric circulation. Arctic clouds are in turn influenced by these elements of the Arctic climate system, and these interactions create the potential for Arctic cloud-climate feedbacks. To further our understanding of potential Arctic cloudclimate feedbacks, the goal of this paper is to quantify the influence of atmospheric state on the surface cloud radiative effect (CRE) and its covariation with sea ice concentration (SIC). We build on previous research using instantaneous, active remote sensing satellite footprint data from the NASA A-Train. First, the results indicate significant differences in the surface CRE when stratified by atmospheric state. Second, there is a weak covariation between CRE and SIC for most atmospheric conditions. Third, the results show statistically significant differences in the average surface CRE under different SIC values in fall indicating a 3-5 W m-2 larger LW CRE in 0% versus 100% SIC footprints. Because systematic changes on the order of 1 W m-2 are sufficient to explain the observed long-term reductions in sea ice extent, our results indicate a potentially significant amplifying sea ice-cloud feedback, under certain meteorological conditions, that could delay the fall freeze-up and influence the variability in sea ice extent and volume. Lastly, a small change in the frequency of occurrence of atmosphere states may yield a larger Arctic cloud feedback than any cloud response to sea ice. [ABSTRACT FROM AUTHOR]

While enormous progress in the determination of the global energy fluxes in and out of the climate system was made in the past decades due to the installation of sophisticated space-born observation systems, substantial discrepancies remained in the estimated and simulated surface energy budgets, as they cannot be directly measured from space. The increasing availability of accurate surface observations, improvements in the satellite retrievals of surface fluxes and model advancement, however, lead to a recent convergence of independent estimates on some of the global mean surface energy balance components to within a few Wm-2. This suggests that we are approaching a stage where we are not only confident in the magnitudes of the global annual mean energy balance components at the TOA, but increasingly also at the surface. Consensus emerges on a global mean surface downward shortwave flux near 185 Wm-2, as well as global mean surface downward and upward longwave fluxes slightly above 340 Wm-2and below 400 Wm-2, respectively. Taking into account remaining uncertainties in the surface albedo, this implies a surface absorbed shortwave radiation near or somewhat above 160 Wm-2, which leaves an atmospheric shortwave absorption of nearly 80 Wm-2, considering a total shortwave absorption of 240 Wm-2 in the global climate system. Thus, 2/3 of the absorption of shortwave radiation in the climate system takes place at the surface, 1/3 in the atmosphere. Given the above estimates, the global mean surface net radiation (surface radiation balance) appears to be around 105 Wm-2. The partitioning of this radiative energy at the Earth's surface into sensible and latent heat is only weekly constrained by direct observations and is still afflicted with considerable uncertainties. The best estimate of global mean surface net radiation near 105 Wm-2 promoted here should, however, enable a consistent representation of the magnitudes of the global energy and water cycles within their margins of uncertainty and thus reconcile previously debated discrepancies between global estimates of surface radiation and precipitation. A challenge remains the adequate representation of the energy balance not only on a global annual mean scale, but also on regional, seasonal and diurnal scales. [ABSTRACT FROM AUTHOR]

The Global Energy Balance Archive (GEBA) is a database for the worldwide measured energy fluxes at the Earth's surface. GEBA is maintained at ETH Zurich (Switzerland) and has been founded in the 1980s by Prof. Atsumu Ohmura. It has continuously been updated and currently contains around 2500 stations with 500'000 monthly mean entries of various surface energy balance components. Many of the records extend over several decades. The most widely measured quantity available in GEBA is the solar radiation incident at the Earth's surface ("global radiation"). The data sources include, in addition to the World Radiation Data Centre (WRDC) in St. Petersburg, data reports from National Weather Services, data from different research networks (BSRN, ARM, SURFRAD), data published in peer-reviewed publications and data obtained through personal communications. Different quality checks are applied to check for gross errors in the dataset. GEBA is used in various research applications, such as for the quantification of the global energy balance and its spatiotemporal variation, or for the estimation of long-term trends in the surface fluxes, which enabled the detection of multi-decadal variations in surface solar radiation, known as "global dimming" and "brightening". GEBA is further extensively used for the evaluation of climate models and satellite-derived surface flux products. On a more applied level, GEBA provides the basis for engineering applications in the context of solar power generation, water management, agricultural production and tourism. GEBA is publicly accessible over the internet via www.geba.ethz.ch. [ABSTRACT FROM AUTHOR]