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We investigated spin-Hall effect (SHE) and degree of MgO (100) orientation in artificially synthesized (W/Hf)-multilayer/CoFeB/MgO systems with various W thicknesses. We found that the artificially synthesized multilayer systems can enhance the spin-Hall effect and control the value of spin diffusion length. We observed a maximum magnitude in both spin-Hall angle and spin-Hall conductivity as a function of W thickness in W/Hf-multilayer systems, and found that the values of spin-Hall conductivity are larger than that for β-phase W. In addition, a more highly oriented MgO (100) texture on CoFeB is obtained for (W/Hf)-multilayer systems prepared under low-Ar-pressure condition, which would be suitable for preparation of magnetic tunnel junctions with high tunnel magnetoresistance properties on (W/Hf)-multilayer heavy metal electrode. These results suggest that the artificially synthesized multilayer system is one of the avenues for realizing spin devices using spin-orbit torque.

Although a high-quality homoepitaxial layer of 4H‑silicon carbide (4H-SiC) can be obtained on a 4° off-axis substrate using chemical vapor deposition, the reduction of defects is still a focus of research. In this study, several kinds of surface defects in the 4H-SiC homoepitaxial layer are systemically investigated, including triangles, carrots, surface pits, basal plane dislocations, and step bunching. The morphologies and structures of surface defects are further discussed via optical microscopy and potassium hydroxide-based defect selective etching analysis. Through research and analysis, we found that the origin of surface defects in the 4H-SiC homoepitaxial layer can be attributed to two aspects: the propagation of substrate defects, such as scratches, dislocation, and inclusion, and improper process parameters during epitaxial growth, such as in-situ etch, C/Si ratio, and growth temperature. It is believed that the surface defects in the 4H-SiC homoepitaxial layer can be significantly decreased by precisely controlling the chemistry on the deposition surface during the growth process.

The binding energy and generalized stacking-fault energy (GSFE) are two critical interface properties of two dimensional layered materials, and it is still unclear how neighboring layers affect the interface energy of adjacent layers. Here, we investigate the effect of neighboring layers by comparing the differences of binding energy and GSFE between trilayer heterostructures (graphene/graphene/graphene, graphene/graphene/boron nitride, boron nitride/graphene/boron nitride) and bilayer heterostructures (graphene/graphene, graphene/boron nitride) using density functional theory. The binding energy of the adjacent layers changes from -2.3% to 22.55% due to the effect of neighboring layer, with a very small change of the interlayer distance. Neighboring layers also make a change from -2% to 10% change the GSFE, depending on the property of the interface between adjacent layers. In addition, a new simple expression is proven to describe the GSFE landscape of graphene-like structure with high accuracy.

We present an enhancement of the fluorescence of shallow ( $ 10 nm) nitrogen-vacancy (NV $^-$ ) centers by using atomic layer deposition to deposit titanium oxide layers on the diamond surface. In this way, the shallow NV $^-$ center charge states were stabilized, leading to the increasing fluorescence intensity of about 2 times. This surface coating technique could produce a protective layer of controllable thickness without any damages to the solid-state quantum system surface, which might be an approach to the further passivation or packaging techniques for the solid-state quantum devices.

We present a conceptually-new approach “dual manipulation effect” using the surfactant passivation and the electron carrier doping for mediating intrinsic ferromagnetism in Co-doped ZnO dilute magnetic semiconductor (DMS) thin films. The first-principles calculations show that the surface passivation by hydrogen serves as a magnetism switch for the Co-O-Co magnetic coupling at the surface of the thin film, and thus can control the spin polarization of the doped Co atoms. Meanwhile, the electron carrier doping can further function as an effective layerlike ferromagnetism mediator for the underneath layer. The dual manipulation effect sheds light on the essential magnetism origin of n-type Co:ZnO DMS thin films, and may be used as an alternative strategy for enhancing the ferromagnetism in other n-type DMS oxides thin films.

A kinetic approach to analytically considering the lateral heat transfer through a metal layer located between two massive dielectrics. The effective transverse thermal conductivity of such a layered system with an arbitrary thickness of the metal layer is calculated, and the thicknesses at which the size effect is manifested in thermal conductivity, are found. The transverse heat transfer is also analyzed using the phenomenological two-temperature (2TM) model, i.e. in terms of electron and phonon temperatures. Comparing the results of 2TM and the microscopic approach allows us to find out the conditions under which the frequently used two-temperature approach is not applicable.

For the current PV production about 2000 tons of silver are consumed per year, 10% of the entire world annual silver supply. The PV production is expected to grow significantly in the next decades in order to enable the energy transition to 100% renewables. Annual production volumes in the terawatt range are predicted already for 2030 and this may lead to higher silver price and put more pressure on the industry to replace silver by copper.Within the Ameliz project several patterning approaches for copper electrodeposition on heterojunction cells are developed: firstly, patterning by printing a metal seed grid with a dielectric layer as plating mask and secondly masking by a monolayer of self-assembling molecules. These molecules consist of a phosphonic acid group and a hydrocarbon chain. They are bonded to the ITO surface and form a monolayer of well-ordered, densely packed hydrophobic chains, which protects the ITO surface against plating solutions. Furthermore, methods for selective formation of a copper seed layer by electrografting and for improved adhesion by ITO reduction are being investigated.

Metal-oxide nanostructures with precisely controlled geometries can play an important role in the technological improvement of sensors for gas detection. In this article we deal with the preparation of sensoric structures of sputtered TiO2 film the aim of which is for detection of environmental gases such as COx, NOx or NH3 and the like. Thin polycrystalline TiO2 deposited on a resistive layer of SiO2 was patterned by Electron-Beam Lithography (EBL) and subsequently Reactive Ion Etching (RIE) etched to obtain controlled geometrical extension of its active area. The increase and enhancement of the TiO2 active area was also controlled by its annealing and Ion Coupled Plasma (ICP RIE) etching through a Hydrogen Silsesquioxane (HSQ) resist mask or eventually an aluminum mask.

We have metallised n+ polysilicon passivated layer structures deposited by Low Pressure Chemical Vapor Deposition (LPCVD) with silver pastes. We analysed recombination at the metal contacts by photoluminescence imaging of metallised lifetime samples and found for the best paste, metal semiconductor recombination current density values (J0met) below 70 fA/cm2, with contact resistivity below 2 mΩcm2. To our knowledge, these are among the lowest values reported so far for full size M2 wafers with 150 nm thin polysilicon layer and wet chemical thin oxide. We also studied the effect of the peak firing temperature on the J0met and contact resistivity in this work. Further, we performed Scanning Electron Microscopy to further understand the silver polysilicon interface.

In this research, the microstructure evolution of Sn-Cu based solder paste on the electroless nickel immersion gold substrate was investigated. The aims are to study the microstructure formation of as-reflowed Sn-10 wt.% Cu paste on the substrate. Besides, the evolution of the interfacial intermetallic compound layer and bulk solder microstructure of the solder joint that subjected to multiple reflowed were also investigated in this paper. The Sn-0.7 wt. % Cu solder paste was mixed with copper powder to produce the Sn-10 wt. % Cu solder paste. The mixed solder paste then reflowed on the electroless nickel immersion gold surface finish substrate to form a solder joint in a reflow oven. Then, the as-reflowed solder joint was undergo multiple reflowed processes until the sixth time. It was noted that multiple reflowed process influenced the microstructure evolution of Sn-0.7 wt. % Cu and Sn-10 wt. % Cu solder samples on electroless nickel immersion gold substrate. The Cu6Sn5 IMC in the bulk solder microstructure for both solder samples become coarsen after 6th times reflowed cycles. Meanwhile, the primary Cu3Sn phase in Sn-10 wt. % Cu solder paste was found to dissolve. The morphology of the needle-shaped interfacial intermetallic compound layer was changed to layer-shape and the intermetallic compound thickness of both solder joints on electroless nickel immersion gold substrate was increased with the number of the reflow process cycles. The grain size and thickness of IMC formation for both solder joints are directly proportional to the multiple reflow cycles.

The prospects of ion-selective treatment for the liquid radioactive waste volume reducing are shown. The main problems of the hydrodynamics scale-up and ion-exchange equipment design are outlined. The short review of the methods of packed bed hydrodynamic processes modeling is presented. The experimental research technique of the required physical properties of the EKOSORB ion-selective sorbents for the hydrodynamic design and scale-up of the liquid radioactive waste treatment ion-exchange equipment is shown. The results of the liquid radioactive waste treatment ion-selective sorbents true and bulk density and porosity measurements are shown. The micro photos and data on the ion-selective sorbents particle’s form, size, and structure are presented. The ion-selective sorbents layer pressure drops were calculated by the Ergun’s equation.

The electronic properties and growth morphology of Si(111)/ZnS heterostructure modified by a GaSe van der Waals termination layer, which provides a chemical and an electronic passivation of the Si(111)���surface is investigated by surface sensitive methods (STM, LEED and SXPS). The van der Waals termination layer suppresses the Si���S interface reaction, which is observed for non terminated substrates. The interface electronic properties are nearly unchanged, but the morphology of the growing ZnS���film is dramatically changed. With the passivation layer ZnS grows as orientated pyramides with a (111) base area surface orientaion and (100)���facets. The sticking coefficient is reduced by a factor of ���10 compared to bare Si(111), where ZnS grows as an untextured polycrystalline layer.

The characteristics of nanocomposite titania/reduced graphene oxide (TiO2/rGO) deposited on a glass substrate with potential application in the energy harvesting device of perovskite solar cell has been examined. The active material TiO2 was deposited on top of a fluorine-doped tin oxide glass substrate via a spin coating method. Reduced graphene oxide (rGO) was then coated onto TiO2 layer to form a nanocomposite TiO2/rGO. Formation and crystal structure of the layer were characterized using X-ray diffraction (XRD), whereas the surface morphology was examined using a field emission scanning electron microscope (FE-SEM). A structural study from X-ray showed that the two phases of TiO2 and rGO are detected, whereas the morphological examination showed that the layer had been homogeneously deposited on the glass substrate. The performance of TiO2/rGO as an electron transport layer in the perovskite solar cell device fabricated with chloride modified perovskite (CH3NH3(Pb/Zn)Cl2I) showed different characteristics with different concentrations of TiO2 and rGO. The highest efficiency of 3.8% was obtained from the composition of 0.0325 M TiO2 and 0.5 vol.% rGO.

Despite being efficient electron injection for the organic light-emitting diode, sub-nanometer ultrathin layer of lithium fluoride requires deposition at high temperature and precise layer thickness. Nontoxic organometallic compounds such as lithium stearate and sodium stearate are tested for electron-injection alternatives, which can be deposited at lower temperatures. In this work, OLEDs with lithium or sodium stearates are found to perform better than the lithium fluoride as electron injection. These devices also manage to achieve 90% maximum luminance and power efficiencies over a broader range of 1.5 - 4.5 nm thick of lithium stearate and 2.5 – 4.0 nm thick of sodium stearate.

Silver nanowires (AgNW) is one of the great candidates to replace the role of expensive and relatively rare indium tin oxide (ITO) as the primary material for transparent conducting electrodes (TCEs). TCEs are essential components in numbers of optoelectronic devices, such as organic light-emitting diode (OLED), touchscreen, and solar cells. The specific attribute of TCEs in both optical transmittance and electrical conductivity offers a possible extraction of electrical carriers while transmitting light through the layer. In this study, AgNW was synthesized using a wet chemistry method and deposited on glass substrates with the method of spin coating. In favor to enhance the performance of TCEs, the optimization of number of deposition and post-treatment annealing at 200 °C on glass substrate was then applied. The Hall Effect and UV-Vis Spectroscopy characterization results show that the Figure of Merit (FOM) of AgNW in this study reaches 6.27 × 10−3 Ω−1 that is comparable with FOM of commercial ITO of 7.16 × 10−3 Ω−1. The present results provide a plausible way to design and fabricate a new alternative material for TCEs with relatively low cost.

Thin films and layers of copper sulfide with CuxS composition were obtained by chemical deposition from aqueous medium on substrates of matted and unmatted quartz. Using scanning electron microscopy and EDX analysis, the features of the morphology and composition of layers on different substrates were revealed. An excess of copper was found in the semiconductor layer. For the films grown on unmatted quartz, the transmission spectra were determined, as well as the optical band gap by processing the Tauc equation. The layers deposited on matted quartz were investigated for photocatalytic activity by oxidation in their presence of hydroquinone under the action of UV radiation.

Recently, hydride ion has attracted much scientific interest, from the viewpoint of fast ion-conduction. It was reported that La2LiHO3 perovskite, which has K2NiF4−type structure, exhibits hydride ion-conductivity. In this study, hydride ion-conducting mechanism on two-dimensional LiOH layer has been investigated, using hybrid density functional theory (OFT) calculations. When hydrogen is allocated at two-dimensional, structural deformation appears, due to O-H-O covalent bonding formation. On the other hand, hydrogen is destabilised at lattice position because of the lability of negatively charged hydrogen.

In this present works, the effect of triphenylphosphine (TPP) on the distribution of carbon layer and size of phosphorus-doped multi-wall carbon nanotubes (P-MWCNTs) were investigated by combination of transmission electron microscopy and image analysis. The P-WMCNTs were synthesized by direct liquid injection catalytic chemical vapor deposition with floating catalyst through decomposition of cyclohexane and triphenyl phosphine, in the presence of ferrocene catalyst on silicon wafer substrate. The change of increase and decrease by the layer thickness of P-MWCNTs was observed upon the increase of TPP concentration from 0.5, 1, to 2%. The findings exhibit that the doping source concentration on P-CMWCNTs synthesis affects catalytic activity the growth of graphitic layer, tube diameter distribution, homogeneity graphitic layer, and homogeneity in diameter distribution in the synthesized P-MWCNTs.

Fabrics with water-proof properties are in high demand now-a-days because of its many engineering applications. In the present research work melt blown polyester non-woven fabric is used as base material and acrylic polymer coating material is used as a coating emulsion to develop waterproof coated fabrics. However, the coating process is completed using roller coating technique by applying the coating emulsion on varying layers of non-woven fabrics. Several technical tests has been conducted on the developed water proof material to assess the durability value of the water-proof coated fabrics. Physical tests like water repellent test, thickness test, Layer peeling test, Air permeability test, coating hardness tests coupled with SEM analysis and thermal property tests are performed on the water-proof coated fabrics. The results of the tests show excellent water repellent characteristics, chemical resistance, breaking strength and excellent durability for wear and tear.

Diffusion of silver(Ag) from the electrode in perovskite solar cell layers in presence of moisture is a serious issue in fabrication of stable halide perovskite-based solar cells (PSC). We witnessed a fast degradation of the fabricated planar p-i-n PSC having device structure as glass/ITO/PEDOT:PSS/MAPbI3/PCBM/Ag. This degradation is due to the presence of ambient moisture and reaction of Ag with perovskite to form silver iodide(AgI). The diffusion of Ag into the layers of PSC was easily noticeable after a few hours of device fabrication. Therefore, to suppress the fast diffusion of silver electrode into the perovskite absorber layer, a thin layer of ITO indium tin oxide(ITO) was incorporated in PSC, between the electron transport layer(ETL) and Ag electrode which modified the device configuration as glass/ITO/PEDOT:PSS/ MAPbI3/PCBM/ITO/Ag. It was observed that the performance and stability of the device with this ITO layer improved significantly compared to the device without ITO. Using intermediate ITO layer, improved the device power conversion efficiency (PCE, η) from 1% to 8%, with open-circuit voltage(Voc) = 0.86V, short-circuit current density(Jsc) = 19.11mAcm-2, and fill factor(FF)=0.49.

RF sputtering was achieved to get Ca3Ce(PO4)3 phase from target of 60wt%CeO2/TCP on stainless steel 316L surface for bioapplication. The selection of ceria and tricalcium phosphate is according to fact the importance of these materials in biomedical media. The produced phase was confirmed by XRD analysis according to (JCPDS card No. 09-0169) with important 2θ values at (≈ 28.4, 33.7, 46.6 and 44.7). The FESEM/EDS exam showed smoother surface with indication to appear this phase through compact layer of deposited particles. The EDS mapping showed the presence of the main elements of substrate in addition to Ce, Ca, P, and O. AFM images shows uniform distribution of particles and this analysis indicates lower average roughness and average diameter for coated specimen compared with the substrate.

Using optical microscopy, evaluation of the ohmic resistance of oil layers in tribocontact, and tribological studies, the results of the influence of the particle size of soft rocks of the serpentine group: antihorites, lizardites, and chrysotiles on the anti - wear properties of liquid lubricants-LUKOIL Standard 10W40 mineral oil and synthetic Castrol SLX 5W40. The optimal size of serpentine particles is 3…5 microns. The inefficiency of serpentine modification of Castrol SLX 5w40 synthetic oil is proved based on the results of wear intensity testing and measurement of the ohmic resistance of the oil layer in tribocontact.

A significant impact of the mining activity is pollution to water, namely acid mine drainage (AMD). One of the efforts that can to reduce the contact of sulfide minerals with oxygen in the air is by identifying minerals in rocks that have the potential to form acidity or Potential Acid Forming (PAF) with those that do not have the potential to form acidity or Non-Acid Forming (NAF). PAf and NAF’s planning for the potential formation of mine acid water is indispensable in open-pit mining activities. Open-pit mining is a method of mining whose activities come into direct contact with the outside air so that the potential for mine acidic water formation will increase due to exposure to oxygen and water directly. The environment will feel a considerable impact from mining activities, so that appropriate environmental control systems are needed to improve the impact of mining on the environment by looking at cover rock layer.

The "Jupiter" field is located in South Sumatera with Talang Akar Formation as the main reservoir and consists of Layers A, B, and C. Layer A is divided into three sub-layers (A-1, A-2, and A-3). In the previous research in Layer A, some development wells and water injection wells had been planned (Farah, S. N., 2016) and used as a Base case. Then the Base case was added with four CO2 injection wells (immiscible and miscible) in the oil zone of the A-1 Layer (Ma'roefi, Rambu Muhammad., 2019). This study will simulate with gas cap CO2 injection to compare with CO2 injection in the oil zone and only focuses on the A-1 sub-layer. The method used in this study was reservoir simulation using CMG GEM Version 2012 simulator. The best scenario was determined by sensitivity of the best injection pattern, the best rate, and the best injection pressure. Based on the simulation results, it is shown that the injection pattern is not so affecting in determining the success of gas cap CO2 injection, the optimum variety of injection rate is 2570 MSCFD, and the optimum pressure is 679 psi. Scenario III-B is more optimum than the best immiscible scenario and would be more optimum if usage of the miscible CO2 scenario, which could give the recovery factor 9.23%.

A numerical study of the melting of a layer of ice scattering radiation located vertically on an opaque substrate under radiation heating has been carried out. To solve the radiation part of the problem, a modified method of average fluxes was used taking into account isotropic scattering and absorption of radiation by the medium, as well as the selective nature of the radiation source. The influence of the spectral volumetric properties of ice on the melting and temperature rise of the non-irradiated side is shown. Comparison of the calculation results with experimental data shows satisfactory agreement.

Biofilm is a thin layer of microorganisms that attaches to a surface of building materials with a slime layer. This layer is not desirable as it is perceived as a factor that degrade an aesthetical functions of buildings. On the other hand, the hygrothermal performance of constructions or their segments might be affected as well which is a phenomenon that is often underestimated. Higher sorptivity, slower diffusion of water vapor or changes of surface properties belong among the most influencing factors. This paper aims at quantification of light reflectance of plasters before and after inhabitation by biofilms. The data obtained experimentally by means of spectrophotometry are then used as input parameters of computational modelling that predicts the heat and moisture distribution in a given wall assembly when exposed to reference weather data for Brno, Czech Republic. The computations showed, that due to the surface inhabitation, the light absorption might reach up to 268.9% when compared to the reference surface which is subsequently reflected also in the thermal performance of the assembly, the plaster in particular. Because of the darker color of the biofilms, the surface heating rate is much higher when insolated. As a consequence, depending on a period of the reference year, the surface temperature might differ by up to 6.06 °C. Such a difference represents a considerable value that might subsequently affect other properties and parameters of plasters including thermal straining, microcracks formation or durability.

Aluminum 5083 is widely used for shipbuilding because of its lightweight and strong resistance to corrosion. However, because of its low hardness and wear resistance, it causes limitations in its application. Because of this, there is a need to improve the mechanical properties of the material surface. To improve the surface mechanical properties of Al-5083, the thin film of titanium nitride (TiN) was deposited with the DC sputtering technique on the surface of Al-5083. The method of deposition has been carried out for varying periods of time such as 60, 90, 120, 150, and 180 minutes with 70Ar:30 N2 of gas ratio. From this time variation, it is expected that the optimal conditions of time can be obtained that produce an optimum hardness. Based on optimum conditions, the deposition process was continued for various of Ar:N2 gas ratio such as 60Ar:40N2, 70Ar:30N2, 80Ar:20N2, and 90Ar:10N2. The effect of thin layer deposition on the material on its hardness was characterized using a Vickers microhardness tester, wear using the Ogoshi method, surface morphology and chemical composition using Scanning Electron Microscopy (SEM) - Electron-Dispersive Spectroscopy (EDS). Based on research done, it was found that the optimum condition of time is reached at 120 minutes and 70Ar: 30N2 of the gas mixture with the highest hardness in order of 94.7 VHN from the initial hardness of 52.14 VHN. At optimum conditions, the wear resistance decreased to 8.25 × 10-8 mm2/kg from the initial 54.8 x 10-8 mm2/kg or increase wear resistance by factor 6.6. At this condition, the maximum thickness layer is about 26.79 µm, and the detected of Ti and N with Ti = 83.2 % wt and N = 0.6 % wt.

As part of the paper, the stress-strain state of the layer with spherical holes for lubricant was analyzed. A part of the sliding layer with one hole for lubricant was considered. The paper deals with an unfavorable case: the lack of lubrication in the recession. A comparison of deformation behavior of a sliding layer part made of three polymeric materials is presented: modified fluoroplastic, anti-friction fluoroplastic-based composite material with spherical bronze inclusions and molybdenum disulfide and high-modulus polyethylene produced in Germany. Physical and mechanical properties of the sliding layer materials were obtained experimentally. The frictional contact interaction of a sliding layer part with a rigid steel plate was considered with the friction coefficients obtained experimentally with and without lubrication on the mating surfaces. For the qualitative description of the numerical experiment, the experimental dependences of friction coefficients as a function of the pressure level were obtained, and approximating functions were constructed to obtain friction coefficients exceeding those technically possible in the field experiment. A series of numerical experiments on the deformation of a sliding layer part with a hole for lubricant with the use of a rigid steel plate and application of pressure from 5 to 90 MPa, which corresponds to the rated loads of the spherical support structures of the bridge spans. The deformed condition of the structure and contact zone parameters were analyzed. Influence of the sliding layer thickness on deformation characteristics of the contact node was studied.

A technology is proposed to increase the efficiency of a perforator for developing oil and gas fields using a cumulative charge with a layer of reaction material (RM) applied to the lining. Calculation, theoretical and experimental work was carried out to study the process of functioning of a cumulative perforator. It was revealed that in the process of compression of cumulative lining (CO), the reaction material is localized on the outer surface of the tail of the formed cumulative jet (CJ). The speed parameters of the formed CJ are presented. For an experimental study, a cumulative charge was made in which RM was deposited on a CO using electrochemical deposition. An x-ray was obtained of the tail of the CJ with a deposited layer of RM as a result of the actuation of the laboratory charge.

In this paper, we aimed to prepare transparent nanofilms (SnO2) using spin coating technique used for solar cell application. It costs is very less for fabrication and by using very less quantity of raw materials. SnO2 is a transparent metal oxide that has verygood electrical, thermal conducting and optical properties. The efficiency of the solar cell nanofilm depends mainly on the thickness of nanofilm layer. The optimizing parameters such as the solute concentration, spin rate, time of the turn table, Nanofilm thickness and heat treatment techniques are to be accounted for good SnO2 production. SnO2 film is prepared from tin chloride as precursor and ethanol as the solvent. Thus nanofilm coated using spin coating techniques is subjected to various characterization techniques to study the nanofilm layer and its applications. The presence of SnO2 is identified by FTIR and the thickness of the layer is measured by Stylus Profilometer. The composition of the materials in the nanofilm are identified by XRD characterization.

The work focuses on the effect of transversal runoff on the high-pressure layer in a supersonic (M = 6) separated compression corner flow. The high-pressure layer is formed behind the reattachment line of the separated flow and is characterized by high values of total pressure (90-95% of the freestream total pressure). The presented experimental results show that the high-pressure layer exists in a flow without transversal runoff.

Over the past decades, the rapid growth of perovskite solar cells (PSCs) has proven to be unprecedented, with power conversion efficiency (PCE) rising to 23.7%, which is on par with traditional silicon solar cells. However, this breakthrough in technology has a natural drawback of the toxic nature in the current perovskite structures. Alternatively, tin-based, and germanium-based perovskite device have been proposed as the most viable substitution. Numerical modelling of both tin-based and germanium-based perovskite devices is simulated by using the General-Purpose Photovoltaic Device Model (GPVDM) and compared against a lead-based device. In this study, the influence of layer thickness is investigated by adopting an inverted device architecture with a variable active perovskite layer. Tin-based and germanium-based perovskite showed their highest performance at 50 nm at 1.76% (JSC of -29.19 A m-2, VOC of 0.89 V, and FF of 0.68) and 2.99% (JSC of 93.32 A m-2, VOC of 0 V, and FF of 1.00), respectively. Both findings are highly positive as compared with its lead counterpart 3.29% (JSC of -55.93 A m-2, VOC of 0.72 V, and FF of 0.81). A further study is still needed as a keen insight to make this technology market viable.

In this work, experimental studies on the dissociation of methane hydrate at different temperatures are carried out. During each individual experiment, the temperature was kept constant. In the area of self-preservation, the rate of dissociation of the gas hydrate decreases many times. The diffusion model of decay (based only on the diffusion coefficient) shows a significant excess of the calculation over the experiment in the region of self-preservation.

In the present paper, we report on the structural investigation of ferromagnetic metal/organic semiconductor bilayer thin films. Ferromagnetic Co thin films with thickness ∼ 150 A were deposited on organic semiconductor Tris-(8-hydroxyquinoline)aluminum, Alq3 thin films with different thickness ranging from 250 A to 900 A. Alq3 thin films were deposited on Si(100) substrates by thermal evaporation prior to the deposition of Co thin films using electron beam evaporation technique. X-ray reflectivity measurements have been performed to determine the internal structure of the bilayer samples. Experimental reflectivity data were fitted using Parratt formalism to gain information about thickness, electron density, and roughness of the individual layer. X-ray reflectivity analysis confirms about 13 nm diffusion of Co into underneath Alq3 layer at the Co/Alq3 interface. It is not possible to clarify whether diffused Co is in the form of atoms or as clusters from the x-ray reflectivity analysis.

Very good mechanical properties and long-term durability make UHPFRC an ideal material for strengthening of existing structures. With a smaller amount of strengthening material, compared to ordinary concrete mixtures, it is achieved a higher load-bearing capacity. Experimental tests on reinforced concrete elements strengthened with a UHPFRC layer in the tensile zone were performed in three phases with regard to the type of stress – bending, shear and punching shear tests. In this paper will be presented results of first part of experiments – bending tests. The aim of the tests was to determine the load-bearing capacity with regard to the thickness of the strengthening UHPFRC layer and to confirm the assumption of interaction with the existing concrete surface layer at different types of loads, using only the suitable surface treatment of the strengthened concrtete element. In all stages of the experiments, the tests were performed on three types of the cross-section, reference and strengthened with thickness of 30 and 50 mm UHPFRC strengthening layer.

This paper discusses issues related to the determination of the stiffness and strength characteristics of samples made of composite materials: reference samples, samples with embedded fiber optic sensors (FOS), samples with an embedded SMART layer. In this work, the SMART layer is understood as a coating that protects FOS at the stage of their introduction into the structure. Comparison and analysis of the influence of the embedded optical fiber and the SMART layer in the structure of the composite on rigidity and strength is carried out. The results of field experiments were compared with the results obtained in the framework of mathematical modeling.

The article discusses the dynamic non-stationary filtration of gas (liquid) in the system of two interacting layers, provided that edge water moves through the developed layer. The changes in time of the position of the gas-water contact, the pressure indicators in the interacting layers are determined. The results of the computational experiment are presented in the form of tables.

The preeminent significant perspective for supporting life on the earth is water. Notwithstanding its bountiful accessibility, a little rate is regularly utilized for drinking reason. By expanding vanishing rate with the joined impact of radiation, the sun based water preheating framework builds the effectiveness of the sun oriented water refining gadget by covers slip temp, water pollution thickness, base plate engrossing thickness and extra warmth. This gadget likewise can be utilized for not too bad water. For this experimentation, we've utilized copper curl with chamber supplanting emptied cylinders to offer significance for sustainable power source assets for reasonable turn of events. The desalination framework works in three distinctive circumstances which fuses ordinary still strategy (without a wick), utilizing single layer cotton wick and twofold layer cotton wick in regular still technique and one without cotton wick. In this manner normal outcomes upheld 7 days when ordinary despite everything utilized delivered 150-160ml of desalinated water with approx. Avg. Bay temp and outlet temp. 37°C and 68°C. Though with the usage of Single layer Wick Cotton it created approx. 252ml of desalinated waterwith approx. Avg. Gulf temp and outlet temp. 37°C and 69°C and with Double layer Wick Cotton it delivered 600ml of desalinated water with approx. Avg. Gulf temp and outlet temp. 41°C and 71°C. The water profitability is spread out by 162%over regular still for single layer cotton wick and thusly the water efficiency is expatiated by 385% over ordinary still for the twofold layer cotton wick and even the water efficiency is more by 237% twofold layer cotton wick over single layer cotton wick.

In the present work, the commercially available Cr3C2-35%NiCr coating powder is deposited by using HVOF thermally sprayed coating on SS 304 Boiler tube steel. The hot corrosion study is conducted on commercially available Cr3C2- 35%NiCr coated SS 304 boiler tube steel and uncoated SS 304 boiler tube steel at 800°C in Na2SO4-60%V2O5 boiler environment with cyclic conditions. The thermo gravimetric method is used to establish the kinetics of hot corrosion by means of weight change method. The commercially available Cr3C2-35%NiCr coated specimen shows very less weight gain as compared to the uncoated specimen. The superior hot corrosion resistance obtained due to the formation of oxide layers consisting of Cr3O3, Cr2O4 &NiO. The uncoated specimen degrades at a faster rate in the form of layer of spalls. The microstructural analysis is examined by using X-ray diffraction (XRD) & scanning electron microscopy (SEM) is used to determine the coating morphology and corrosion products.

With the combination of both electrical approach and optical approach, this paper investigates the n-i-p perovskite solar cell with the most optimized design structure. The proposed approach is mainly based SCAPS-1D Simulator. Here the experimental results of CH3NH3PbI3 perovskite solar cell device are compared to SCAPS-1D simulation results and obtained high power conversion efficiency by optimizing the device parameters. In this paper the change in the parameters of the device like defect density,interface defects,carriers cross sections and doping concentration of Absorber Layer, Electron Transport Layer(ETL) and Hole transport Layer(HTL) are observed with their effect on the performance of the device. The efficiency of preliminary structure of the solar cell device is 19.08% in case of experimental work and 15.8% in case of SCAPS simulation. Then after optimizing the device parameters, the final performance parameters are enhanced to 1.79 V of open circuit voltage(Voc), 40.35% Fill Factor, 22.33% Optimized Power Conversion efficiency and short circuit current(Jsc) of 30.83mA/cm2.

In this we have simulate a p-i-n solar with SCAPS-1D solar photovoltaic device simulator to observe the effect anti reflecting coating over p-i-n solar Device. The device was constructed using GaP. GaAs were used as P+, P, i, n+,n layer with changing doping in it. table it is quite clear that there is there is significant impact of this layer in p-i-n PV Device. In the device of p+-p-i-n-n+ we have observed 36.948% efficiency with anti reflective coating. But without anti reflective coating it went down only at 24.3850%. Almost 12% varies with layer here. In the device of p+-p-i-n we have observed 33.5399% efficiency with anti reflective coating. In the device of p-i-n we have observed 33.4215% efficiency with anti reflective coating. But without anti reflective coating it went down only at 22.0723%. Almost 11% varies with layer here. So, it can be said that, anti reflecting coating reduces the loss and increases the efficiency of a p-i-n PV Device.

Contact deformation behavior of elements of spherical support structures of different geometrical configuration was considered: with anti-friction layer located in the lower steel slab and with anti-friction layer applied to the spherical segment. Within the framework of the paper, numerical analysis of the effect of the anti-friction polymeric layer face angle of spherical support structures on the deformation behavior of the work as a whole and changes in the parameters of friction contact zones, in particular, was performed. On average, the maximum contact pressure level of the spherical support structure model with a layer located in the lower slab is 8.5 % lower, and the maximum level of normal-to-surface movements is more than 28% lower than that of the second model considered. The opening of the contact near the edge of the anti-friction layer approximately by 1% of the surface is observed in all considered variants of spherical support structures. Areas of contact detachment of the interface surfaces in the model with an anti-friction layer in the lower slab are observed at a face angle of 20 degrees or more. For the model with an anti-friction layer applied to the spherical segment, an opposite situation is observed, namely, the contact opening occurs at the face angles from 0 to 10 degrees. In general, with an increase in the face angle from 0 to 30 degrees, there is an increase in deformation parameters of the contact node and parameters of contact zones.

Organic solar cells are potential for the conversion of sunlight into electricity due to their easy to fabricate and inexpensive nature. The main limitation of these solar cells is their relatively low efficiency. In this study, Ag-SiO2 core-shell nanoparticles with different arrangements were placed 1 nm beneath the Indium Tin Oxide (ITO) layer to increase light absorption in the active layer of organic solar cells. A two-dimensional arrangement of core-shell nanoparticles was realized into two models, namely the shift array model and the dual periodicity array model. In the shift model, the position of nanoparticles in the neighboring row was shifted 10-100 nm, while in the dual periodicity model, the distance between nanoparticle in one row was varied 60-100 nm. The calculation of absorption enhancement was performed using the finite element method. Both models were found to enhance light absorption in the active layer of organic solar cells. The optimum absorption enhancement of 98% occurs in the dual periodicity model when the distance between neighboring particles is 60 nm. Increased absorption in the active layer occurring due to the localized surface plasmon resonance phenomenon increases the efficiency of organic solar cells.

The vertically aligned ZnO nanosheet is used as the photoanode in photoelectrochemical water splitting in this study. A nanosheet is a 2D structure which offer improvement over a 1D counterpart such as nanorod or nanowire in terms of increasing the active surface area while still maintain the beneficial electron transport properties to some degree. Furthermore, by growing the nanosheet in vertically aligned manner, the surface area can be larger than the horizontally grown counterpart. In this study, the electrodeposition method is used to grow the vertically aligned ZnO nanosheet. Galvanostatic mode is used with current density of -1, -3 and -5 mA/cm2 applied for 1500, 500 and 300 s, respectively (same amount of charge density). The obtained structure is the nanosheet layer as a majority part grows on top of an under- layer. The height of the nanosheet and the morphology of the under-layer are affected by the current density applied during the electrodeposition. The effect of the unique structure as the photoanode in photoelectrochemical water splitting is discussed.