Bottom Material Research Articles

Speciation of Radium-226 in the Components of Terrestrial and Aqueous Northern Taiga Ecosystems in a Former Radium Production Site

Abstract—The paper considers the content and geochemical mobility of 226Ra in surface waters, bottom sediments, and radioactively contaminated soils (podzolic and alluvial–soddy) of the northern taiga subzone in the area of former radium production site. It is established that the level or radioactive contamination and specific activity of geochemically mobile radium in the podzolic soil is higher, while its migration with surface waters is lower (0.03 Bq/L) than in the alluvial–soddy soil. The drainage waters of the latter are characterized by the maximum radium content (0.55 Bq/L), which is mainly concentrated in the suspended matter (98%) and humic acids (97%) fractions. In the river waters, radium is mainly accumulated in the suspended fraction and fulvic acid compounds. It is shown that under low-temperature and high-water current conditions and a weak sorption capacity of bottom material, the specific activity of the radioactive element in the riverine sediments in the zone of anthropogenic impact is higher than the average background value (0.3–1.8 against 0.2 mBq/g). Sedimentation of radionuclide in the geochemically mobile and weakly mobile species is most intense within contaminated sites. The radium content in the “carbonates”, “sesqui-oxides and -hydroxides” and, especially, “exchangeable” fractions extracted from soils was higher than in other fractions. A cumulative fraction of “water soluble”, “organic matter”, and “amorphous silicates” groups accounts for 0.4–3.7 and 1.6–7.4% of radionuclide content in the podzolic and alluvial–soddy soils, respectively, and was characterized by the predominance of “organic matter” fraction. The fraction of geochemically mobile radium is negatively correlated with its bulk specific activity (r = –0.81), which is noted as trend for bottom sediments. The contribution of insoluble residue in the radionuclide specific activity was 23.5–95.5 and 7.8–69.4% in the podzolic and alluvial–soddy oils, respectively.

Distributions of Potential and Contact-Induced Charges in Conventional Organic Photovoltaics.

The interfaces of dissimilar materials play central roles in photophysical events in organic photovoltaics (OPVs). Depth profiles of electrostatic potential and contact-induced charges determine the energy-level lineup of the frontier orbitals at electrode/organic and organic heterointerfaces. They are critical for the elementary processes in an OPV cell, such as generation and diffusion of free carriers. A simple electrostatic model describes the energetics in organic heterojunctions supported by an electrode, and experiments via photoelectron spectroscopy and the Kelvin probe method validate the potential distribution in the stacking direction of the device. A comparative study has clarified the significance of Fermi-level pinning and resulting electrostatic fields in determining the energy-level alignment. In this review, we discuss how parameters of device constituents affect the distributions of potential and the dark charges in conventional OPVs comprising metallophthalocyanine and C60 as donor and acceptor, respectively. The results of previous studies, together with additional numerical simulations, suggest that a number of the factors influence the depth profiles of the dark charge and potential, such as the work function of bottom materials, layer thickness, structural inhomogeneity at interfaces, top electrode, and stacking sequence.

Utilization of marine clay as a bottom liner material in engineered landfills

Abstract A typical Malaysian marine clay was evaluated for its suitability as a bottom liner material to minimize leachate migration in engineered landfills. Grading, plasticity characteristics, unconfined compressive strength, volumetric shrinkage strain, permeability, geochemistry, mineralogical, and microstructural tests were conducted to characterize the clay as well as to evaluate it’s potential as an effective bottom liner material. The work findings reveal that the clay possesses minimal shrinkage potential and adequate strength to support the overburden pressure imposes by the waste. The permeability of the clay increased upon permeation with leachate but still met the Malaysian regulatory requirement of ≤ 10−8 m/s specified by the regulatory authority. X-ray diffraction analysis shows that the soil mineralogical composition was unaltered after permeation with leachate. Nonetheless, the appearances of two new low-intensity hercynite peaks were observed for the leachate permeated sample. These new peaks, however, did not adversely affect the hydro-mechanical properties of the clay. The results demonstrate that the studied marine clay can be employed as a bottom liner material in engineered landfills, hence providing a value-added application of the construction waste material.

Self-Powered Membrane Sensor for Active Nitrogen Dioxide Detection and Respiratory Analysis

Introduction Nitrogen dioxide (NO2) is a ubiquitous hazardous gas species that can cause light pollution, acid rain [1-3], and water pollution [4]. With increasing vehicles ownership and emission, exhaust from automobiles, i.e. nitrogen dioxide (NO2) and its derivatives, imposes huge threaten on the air quality and public health. However, a majority of the gas sensors demand additional energy supply and undoubtedly increase the energy consumption of the whole device, inhibiting the portability and mobility of the device.A bionic alveolus-shaped triboelectric gas sensor (ATGS) has been designed and fabricated for spontaneously NO2 detection at room temperature. Furthermore, a sensing modeling was proposed by combining the thermodynamic analysis and finite element calculation together with phase-field simulation. This work not only provides a facile, low-cost and portable approach for active gas sensing and real-time physiological assessment, but also proposes a theoretical modeling for self-powered gas detection. Device fabrication The configuration of ATGS is based on contact-separate mode Triboelectric Nanogenerator (TENG). A layer of acrylic with the dimension of 40mm×40mm×1mm was tailored by laser etching machine, together with a layer of latex with the dimension of 40mm×40mm×0.2mm was cleaned by ethanol and deionized water. Then copper electrode with a thickness of 200nm was coated on the one side of the tailored acrylic sheet by thermal evaporation, followed by deposition of prepared suspensions as the gas sensitive material via gas spraying. Subsequently, the WO3/copper coated acrylic sheet was etched through laser etching machine to create a central hole with diameter of 4.0 mm. Then, the latex layer was attached to WO3/copper coated acrylic sheet to form the gas test chamber. Epoxy resin was used to seal the edges between latex film and acrylic sheet to ensure the gas tightness. A plastic tube was integrated as the inlet and outlet of the target gas into the sensor. Method The internal combustion engines burning fossil fuels generate and release huge amount of nitrogen dioxide, which is large threat to environment and public health, as shown in Figure 1a. To address the concern, we designed an alveolus-shaped triboelectric gas sensor (ATGS) for both nitrogen dioxide detection and personal breath behavior monitoring, as the configuration shown in Figure 1b. It was vertically laminated with latex, sensitive material, copper electrode and a plastic air conduit serving as the gas conducting channel. Here, latex film is selected as the contacting layer for its good stretchability and strong electron affinity. Figure 1c shows the photograph of the as-fabricated AIMS, where the gas inflation will hold up the latex membrane to form a tent while the deflation will shrink the tent. During this processing, the latex forms a cycle of contact and separation with the bottom substrate material, pumping the electrons to flow back and forth between the copper electrode and the ground. The working principle and finite element calculation of the as-prepared AIMS is elucidated in Fig. 1d and 1f. Results and Conclusions To explore the gas sensing capability of the as-fabricated ATGS, the output voltage versus NO2 gas concentrations from 0 ppm to 100 ppm were investigated. Compared with 0.01 g and 0.1 g alkali treatments, the device with 0.02 g NaOH treatment revealed a much better sensitivity and linearity, as shown in Fig. 2a, where a response of 452.44% was achieved when being exposed to 100 ppm NO2. In addition, as presented in Fig. 2b, a linearity of 0.976 is observed for the AIMS with 0.02 g NaOH treatment, demonstrating its capability of actively detecting nitrogen dioxide in a wide concentration range. The ATGS also demonstrated capability in distinguishing diverse breathing patterns without any power supply (Fig. 2c). In addition, the NO2 response is at least 20 times higher than other gases, implying a good selectivity (Fig. 2d)A phase-field simulation and finite element calculation were implemented to numerically verify the permittivity effect on the electric field and polarization of sensitive film. As shown in Fig. 3k, the polarization increases with increasing relative dielectric constant, while the electric field follows an opposite trend. Given the depolarization field is proportional to the polarization once the device is fixed, the increase of permittivity facilitates the depolarization of the sensitive layer, which is in agreement with the aforementioned theoretical derivation and experimental data.

Scientific cruise research 2019

The article provides information on the first results of the study of bottom material taken during geological works in the framework of complex research expeditions "Danube-2019" and "Black Sea-2019" in accordance with the Agreement on Scientific and Technical Cooperation between Scientific Hydrophysical Centre of the National Academy of Sciences of Ukraine and State Hydrography Service. The purpose of expeditionary geological research was to obtain relevant empirical data on general trends in changes in bottom topography and main features of floor surface and sedimentation.Comprehensive expeditions collected factual data on the hydrographic, hydroacoustic and hydrological status of the studied waters and in a test mode made geological sampling of the bottom of the North-Western shelf coastal part of the Black Sea and the Danube mouth (within Ukraine) using developed and prepared equipment. Information about the works was added to the oceanographic data bank of the National Academy of Sciences of Ukraine. The practical significance of the obtained results is to field test the technology of geological sampling and further cameral work.

RETRACTED ARTICLE: Study on metal mine detection from underwater sonar images using data mining and machine learning techniques

Ocean mines are the major threat to the safety of great vessels and other living beings in the marine life. It is a self-contained explosive device placed in water to destroy ships or submarines. Due to various factors like variations in operating and target shapes, environmental conditions, presence of spatially varying clutter, compositions and orientation, detection and classification of sonar imagery with respect to underwater objects is a complicated problem. It is well known that many post processing techniques in image processing have done to receive high resolution images to distinguish the objects. However the mentioned technique needs a special method to detect the metal from the usual sub bottom materials mainly rocks. Hence the data collection made in simulated environment locating metals in rock bed and collected with the sonar and the distinguished features of metals from rock have been identified with the totally different approach called intruder detection technique using data mining/machine learning. This paper proposes a novel approach for discriminating and detection of objects in underwater environment with accuracy of 90% (full feature set) and 86% (selected feature set). Hence, it is quite revealing that the new technique is better in classification of mine like objects in underwater, justified with samples of sonar data sets.

Computational study of stack/terminal topologies for perovskite based bifacial tandem solar cells

With the rapid progress on perovskite (PVK) and bifacial solar cells, there is a huge interest in integrating PVK with established technologies such as crystalline silicon (c-Si) and CIGS for bifacial tandem structures. Here we use self-consistent optical/electrical simulations to compare various stack/terminal configurations for bifacial tandem solar cells having PVK as the top cell. In particular, we compare a non-conventional three-terminal four-junction (3T-4J) twin bifacial tandem configuration with standard two-junction bifacial tandem structures having a monolithic two-terminal (2T-2J) or mechanically stacked four-terminal (4T-2J) integration. We show that the optimal design of 2T-2J cell is strongly albedo dependent – the cell designed for a given albedo will perform sub-optimally for other albedo due to the current-matching constraint. A mechanically stacked 4T-2J cell, on the other hand, can perform optimally for a broad range of albedo, albeit at the cost of additional processing complications. The 3T-4J twin tandem cell could offer a relatively simpler process through back-to-back bonding of two identical monolithic 2J tandem cells with superior utilization of albedo in a broad range. The potential benefit of 3T-4J cell could however be limited due to a high front reflection, hence necessitating anti-reflection approaches. We further quantify the effect of bottom subcell material on the efficiency for PVK tandem cells. Using state-of-the-art bottom subcells, efficiency of 33% and 30% respectively could be achieved at the average Earth albedo of ∼30%. By integrating advanced anti-reflectance techniques, the absolute cell efficiency could further be improved by ∼4%.

Tidal Dynamics Control on Cold-Water Coral Growth: A High-Resolution Multivariable Study on Eastern Atlantic Cold-Water Coral Sites

Cold-water coral communities form complex benthic ecosystems in a distinct part of the water column. The exact processes supporting reef growth and changes with time are still partly unsolved. Recent studies have suggested a tidally driven hydraulic control of flow over topographic features as a driver for local downwelling at cold-water coral sites. This mechanism forms a link between surface and coral growth depths and is a driver of resuspension of the bottom material. Only few studies have concentrated on how these processes vary with the health status and structure of the cold-water coral occurrences. In this study, we explore the processes over tidal cycles by analysing in situ stratification, hydrography and velocity data which we then combine with local topography from seven Lophelia pertusa dominated eastern Atlantic cold-water coral sites. The “quality” of coral sites varies from thriving reefs to declining and dead coral sites. We show that living and healthy corals are concentrated at sites, where local hydrodynamics create overturning and mixing which support food supply for filter-feeding corals.

Effect of biaxial stress state on seismic fragility of concrete gravity dams

Dams are important structures for management of water supply for irrigation or drinking, flood control, and electricity generation. In seismic regions, the structural safety of concrete gravity dams is important due to the high potential of life and economic loss if they fail. Therefore, the seismic analysis of existing dams in seismically active regions is crucial for predicting responses of dams to ground motions. In this paper, earthquake response of concrete gravity dams is investigated using the finite element (FE) method. The FE model accounts for dam-water-foundation rock interaction by considering compressible water, flexible foundation effects, and absorptive reservoir bottom materials. Several uncertainties regarding structural attributes of the dam and external actions are considered to obtain the fragility curves of the dam-water-foundation rock system. The structural uncertainties are sampled using the Latin Hypercube Sampling method. The Pine Flat Dam in the Central Valley of Fresno County, California, is selected to demonstrate the methodology for several limit states. The fragility curves for base sliding, and excessive deformation limit states are obtained by performing non-linear time history analyses. Tensile cracking including the complex state of stress that occurs in dams was also considered. Normal, Log-Normal and Weibull distribution types are considered as possible fits for fragility curves. It was found that the effect of the minimum principal stress on tensile strength is insignificant. It is also found that the probability of failure of tensile cracking is higher than that for base sliding of the dam. Furthermore, the loss of reservoir control is unlikely for a moderate earthquake.

All Antimony Chalcogenide Tandem Solar Cell

A proof‐of‐concept tandem solar cell using Sb2S3 and Sb2Se3 as top and bottom cell absorber materials is demonstrated. The bandgaps of Sb2S3 and Sb2Se3 are 1.74 and 1.22 eV, perfectly satisfying the requirement of tandem solar cells. The application of few‐layer graphene enables high transmittance and excellent interfacial contact in the top subcell. By controlling the thickness of the top cell for maximizing the spectral application, the tandem device delivers a power conversion efficiency of 7.93%, which outperforms the individually optimized top cell (5.58%) and bottom cell (6.50%). Mechanistical investigation shows that the tandem device is able to make up voltage loss in the subcells, which is a critical concern in the current antimony chalcogenide solar cells. This study provides an alternative approach to enhancing the energy conversion efficiency of antimony selenosulfide.

Significantly enhanced energy storage density of epitaxial Ba0.53Sr0.47TiO3 thin films by optimizing bottom electrode material

Electrode materials of dielectric thin-film capacitors have significant effect on their energy storage properties. In this work, Ba0.53Sr0.47TiO3 thin films were successfully deposited on LaNiO3 or La0.7Sr0.3MnO3 buffered (001) SrTiO3 substrates by pulsed laser deposition method (abbreviated as BST/LNO/STO and BST/LSMO/STO, respectively). The effect of LNO or LSMO bottom electrode on energy storage properties of BST films was systematically studied. It was found that the recoverable energy density of BST/LSMO/STO films is 36.1 J/cm3 at 3400 kV/cm, which is 59.1% higher than that of BST/LNO/STO thin films, i.e., 22.7 J/cm3 at 2765 kV/cm. Besides, the breakdown strength of the BST/LSMO/STO thin films is 22.9% higher than that of the BST/LNO/STO films. Both films show the good thermal stability from 20 °C to 160 °C as well as excellent fatigue resistance after up to 109 electrical cycles. The results show that the lattice mismatch strain of the film, surface roughness of the electrode and Schottky barrier height at the electrode-dielectric interface greatly affect the energy storage properties of BST thin-film capacitors. Our work offers a practical methodology to enhance the energy storage performances of thin-film capacitors by optimizing bottom electrode materials.

Growth mechanism of highly oriented layered Sb2Te3 thin films on various materials

Sb2Te3 is a layered material with outstanding properties leading to applications in interfacial phase-change memories, spintronic and thermoelectric devices. For successful integration in devices, controlling the orientation of the atomic planes of Sb2Te3 deposited by sputtering on various materials used for electrodes and on dielectric layers is required. We have succeeded in depositing Sb2Te3 thin films (thickness in the range 10–100 nm) by sputtering in industrial deposition equipments on WSi, TiN, amorphous Si as well as on native and thermal silicon oxide layers. The structure and orientation of the films were studied by x-ray diffraction. The Sb and Te planes are found parallel to the substrate, whatever the nature of the bottom material, provided that the sputtering conditions avoid a Te deficiency in the deposited film. These results show that deposition of Sb2Te3 with out-of-plane orientation on silicon oxide is actually possible, in contrast with previous literature results. Scanning transmission electron microscopy images of the interface between the Sb2Te3 film and the bottom material allow to elucidate the growth mechanism. The formation of a surface layer containing a few Te planes on top of the bottom material is mandatory for the subsequent growth of an out-of-plane oriented Sb2Te3 film by van der Waals epitaxy.

Surface dynamic deformation of LY2 aluminum alloy subjected to a laser shock wave planishing technique with different kinds of contacting foils

In this paper, a laser shock wave planishing technique (LSWP) was used to treat the LY2 aluminum alloy surface with corrugated structures, and the influence of contacting film material on the planishing effect was studied. The dynamic response characteristics of surface micro-features under different physical parameters of contacting foils were simulated by finite element simulation (FEM), and experimental verification was carried out. A close match between the experimental results with these simulation results in FEM was found. The planishing of surface micro-protrusions can reduce the surface roughness of treated sample, and the lifting of bottom materials can ensure the surface profile accuracy. The results demonstrate that the planishing effect on micro-protrusions improves with the density of the contacting foil decreasing; The lifting effect on the bottom material enhances with the strength of the contacting foil increasing. A high modulus of elasticity contacting foil also facilitates the bottom material bulging.

Special aspects of explosive loosening with minimal rock displacement

The dynamics of the development of an industrial mass explosion at deceleration intervals of 150x200 ms on a frame-by-frame video recording on a consumer video camera with a shooting frequency of 25 frames per second is studied. Possibilities of visual assessment of the explosion site of individual borehole charges are evaluated. The main difficulties in recording processing are caused by the difference in the intervals between frames (40 ms) and decelerations between charges (50 ms). A significant deviation of the actual deceleration intervals from the nominal value was revealed, which significantly changes the actual picture of the development of a mass explosion, including an increase in the actual development time of a mass explosion against the calculated one. The passage through the zones of the location of individual borehole charges up to 40 stress waves was established. Such multiple impacts of stress waves are expressed in a decrease in the magnitude of the interval velocities of dust and gas emissions as the number of impacts of stress waves increases. Due to the multiple effects of stress waves in the extension stage, the fracturing of the rock mass increases. This is expressed in a decrease in the dynamics, and then in the termination of the outburst of bottom hole material as the disturbance of rocks in the prefracture zone increases. There is no breakdown of rocks; the “ore-rock” contacts have retained their original position, which makes it possible to reduce the dilution of ore to a minimum.

Analysis of Vibration of Slab Track in TBM Tunnel According to Bottom Filling Materials

Due to the high speed of railway and the railway network passing through an urban area, the construction of tunnel using tunnel boring machine (TBM) has been increasing. During TBM tunneling, a deep filling section, about 3 m in depth, under the slab track is formed by the circular machine head. The research and the design standards for filling this section are currently insufficient. In addition, when the section is filled with lean concrete, it may negatively affect the propagation of train vibration. Therefore, it is necessary to analyze the dynamic behavior of filling materials and follow a suitable filling method. In this study, laboratory tests were conducted to determine the dynamic properties of bottom filling materials. Granular crushed stone with a cement content of 7-13% was selected as the filling material. Numerical analyses that reflect the results of the laboratory tests were also performed to analyze the dynamic behavior of the filling section under slab track. The results of these analyses showed that resonance occurred in the filling section depending on the critical and subcritical speeds of the vehicle. Keywords: TBM Tunnel, Bottom Filling Materials, Vibration of Slab Track, Resonance

Modeling and validation of photovoltaic thermoelectric flat plate collector (PV-TE-FPC)

In this paper, a thermal model based on energy balance equations has been developed for photovoltaic thermoelectric flat plate collectors (PV-TE-FPC). The discussed PV-TE-FPC consists of a semitransparent PV module integrated with TE modules to increase the electrical efficiency and a tube-in-sheet arrangement placed below the TE modules for the flow of water and removal of thermal energy from the bottom surface of TE modules. The semitransparent PV module considered in the present study includes polyethylene terephthalate (PET) as the top and bottom cover material of the PV module, which offers the advantages of flexibility, transparent, thermal conductive. The developed thermal model has been experimentally validated by performing statistical analysis for fluid outlet temperature for the measured climatic parameters of Buraidah, Saudi Arabia in the months of February, March, and April 2019. The results illustrate a reasonable agreement between the theoretically calculated and experimental values.

Impact of environmental variables on Sipuncula species along the Aegean and Levantine coasts of Turkey

The faunistic analysis of soft bottom benthic materials collected from the Aegean and Levantine coasts of Turkey in August 2016 and 2017 revealed a total of 7 sipuncula species and 975 individuals belonging to 6 genera. The maximum population density of sipunculans was found to be 1790 ind.m−2 in the Aegean Sea and 730 ind.m−2 in the Levantine Sea. Onchnesoma steenstrupii steenstrupii was the most dominant species, comprising 83.1–92.8% of the total number of specimens in the Aegean Sea and 87.2–96.2% of the total number of specimens in the Levantine Sea. Four major sipunculan assemblages were found in the regions, and the main environmental factors controlling these assemblages were depth, temperature, salinity, the sediment grain size, nutrients and total organic carbon. Different abiotic factors affected the distribution of different sipunculan species in the regions. The present study included two cryptogenic sipunculan species; Apionsoma (Apionsoma) misakianum and Aspidosiphon (Aspidosiphon) mexicanus.

An extremely fast, energy-efficient RESET process in Ge2Sb2Te5 phase change memory device revealed by the choice of electrode materials and interface effects

Phase change memory (PCM) offers promising features such as high speed, non-volatility for ‘universal memory’, however, achieving low-power RESET process in sub-ns timescale is a key challenge. In this study, we display a trade-off between speed and power to enable an ultrafast (sub-ns) and yet, low-power (sub-mW) RESET operation in a nanoscale pore-type Ge2Sb2Te5 (GST) PCM device by means of the choice of electrode materials and their interface effects on a well-designed device architecture using TCAD simulation. The miniaturized device with 20 nm contact diameter (CD) is investigated by employing three different bottom electrode materials, namely TiAlN, TiW and TiN, where the latter is found to be efficient for low-power RESET (159 μW) using a pulse-length of 40 ns showing 63% and 44% power reduction as compared to TiW and TiAlN respectively. A strong interface effect that exists between GST/TiN and GST/SiO2 helps to achieve low-power RESET operation. Furthermore, low-energy RESET is realized using ultrafast (400 ps) pulse with IRESET of 529 μA leads to ∼100× reduction in energy consumption (578 fJ). Moreover, an extremely fast RESET operation in 200 ps is displayed by the simulated device with TiN and TiAlN electrode materials. Hence, our simulation results of ultrafast (200 ps), ultralow-energy (578 fJ) and low-power (159 μW) RESET process with the significant role of interface effects would be highly useful towards designing ultralow-energy PCM device for future electronics.

Interaction of landfill leachate with olivine-treated marine clay: Suitability for bottom liner application

Abstract The interaction between landfill leachate and olivine-treated marine clay was studied to assess its chemical compatibility for suitable application as a bottom liner material in engineered landfills. Soil specimens were prepared using three compactive energies (reduced, standard, and modified Proctors) at -2, 0, +2, and +4% moisture contents of the optimum moisture content and treated with up to 35% olivine content. Index properties, volumetric shrinkage strain (VSS), unconfined compressive strength (UCS), and hydraulic conductivity (HC) tests were conducted. Overall acceptable moisture content range for which the specimens are apt as a bottom liner material was obtained. Test results demonstrate improvement in the UCS, HC, and VSS with increasing olivine content up to 30% olivine content when all three compactive efforts were employed. Formation of magnesium aluminate hydrate (M-A-H) and magnesium silicate hydrate (M-S-H) were the key components responsible for this hydro-mechanical properties improvement and were confirmed using morphological and mineralogical analyses. Based on the obtained overall acceptable moisture content range, all olivine-treated samples met the required specifications over a range of moisture content varying between 9.5 and 20.9% depending on the compactive efforts. These findings indicate that compacted marine clay treated with up to 35% olivine content can be utilized as a potential barrier material in engineered landfills with optimum results at 30% olivine content.

Structural and electrical study of highly (100)-oriented KNN films fabricated by a sol-gel non-alkoxide process

Fabricating of highly-oriented pure-phase potassium sodium niobate (KNN) films on traditional Si substrates by low-cost manageable sol-gel technique (especially with non-alcohol niobium salt Nb2O5 as niobium source) is still a work of great challenge. Here, KNN films were prepared on Pt/Ti/SiO2/Si and LNO/Si substrates via a sol-gel non-alkoxide process. And a comprehensive set of experimental investigations to the role of the bottom electrode, annealing atmosphere and the number of coating layers on the microstructures and electrical properties involution of spin-coated KNN films were made. The crystal structures, preferential orientation and morphology of KNN films are strongly affected by the annealing atmosphere, as well as the bottom electrode material. KNN films annealed in air show an obviously better crystal structure and denser surface than that annealed in oxygen, and KNN film spin-coated on LNO bottom electrode and annealed in air exhibits a dominant (h00) orientation with a high preferred degree of 93.6%. In addition, it also can be found that the increasing number of coating layers of KNN films also results in better crystalline structures (higher oriented degree, larger grains, narrower FWHM) and electrical performance. KNN film with 18 layers shows the largest dielectric constant of 868 and the lowest loss tangent of 2.8%.