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The efficient buffer space management in intermittently connected Internet of Things (IC-IoT) is of great importance for data delivery performance guarantee in such networks. This paper considers two typical buffer space management policies for IC-IoT, i.e., buffer-space sharing (BS) and buffer space allocation (BA). The BS policy allows the buffer space of each device to be fully shared by the exogenous packets and the packets from other devices, while the BA policy divides the buffer space into the source buffer and relay buffer for storing the two kinds of packets separately. With the help of queueing theory and Markov chain theory, we develop a theoretical framework to capture the sophisticated queueing processes for the buffer space under either BS or BA policy, which enables the limiting distribution of the buffer occupation state to be determined. We then provide theoretical modeling for throughput and expected end-to-end delay to evaluate the fundamental performance of the IC-IoT under the BS and BA policies. Finally, extensive simulation and numerical results are presented to validate theoretical models and to demonstrate the effects of BS and BA policies on the IC-IoT performance.

This paper investigates the dynamic recovery policies for liner shipping services with the consideration of buffer time allocation and uncertainties. The aim of this study was to allocate the buffer time at the tactical level and then determine optimal options of actions, including speed optimisation strategy, port skipping and acceleration rate choice, for recovering from disruptions due to various uncertainties or random adverse events, which cause vessel delays. To achieve this, an attempt was made to obtain the optimal balance among economic, environmental and service reliability objectives. A novel mathematical formulation is introduced to solve the robust vessel scheduling problem with short- and long-term decisions. Furthermore, two heuristics were tested to solve the proposed model. Experiments on a container liner shipping service showed the validity of the model and a set of managerial insights were gained from them.

For the landing legs with single air chamber in the buffer structure of the reusable landing vehicle, the geometric topological models and the dynamic model associated with the hard points of the landing legs are established. The geometric constraint relationship in the design of the landing legs is also obtained. The whole vehicle dropping test is conducted, and the test results agree well with that of the simulation model, which validates the dynamic model. Based on the verified model, the effect of hard point positions on the performance of the landing system is analyzed. The multidisciplinary collaborative optimization algorithm and archive-based micro genetic algorithm (CO-AMGA) are used to optimize the design parameters that contain the hard points and the damper. Compared with artificial iteration, the maximum landing impact acceleration response of the vehicle and the buffer struct maximum force are reduced by 30.70% and 14.51% respectively, and the maximum length of retractable pillar decreases by 8.54% while the design margin increases by 69.11%. The proposed optimization method is efficient and can greatly facilitate the design of landing legs.

The development of solid-state lithium-metal batteries (SSLMBs) is severely constrained by the poor physical and (electro)chemical stability of the interface between solid-state electrolytes (SSEs) and lithium (Li) metal anode. Here, a flexible rGO film with uniformly distributed ZnO is in situ constructed at the interface between NASICON-type Li1.5Al0.5Ge0.5(PO4)3 (LAGP) and Li metal anode. Such a buffer layer realizes a good interfacial contact, and prevents the side reaction between the Li metal anode and LAGP. As a result, the symmetric cells with the designed structure present a high critical current density of 3.0 mA cm˗2 and stable cycling for over 800 h at 0.15 mA cm˗2. In addition, LiFePO4 (LFP)/Li full batteries deliver excellent capacity retention and long cycling performance.

1. Organic matter, buffer capacity, and the relation of changes in reaction to the solubilities of the mineral nutrient elements in six samples of Toa silt loam were studied. 2. The buffer characteristics may vary rather widely within a given soil type. The buffer curves for different samples of Toa silt loam show that the presence of larger amounts of organic matter markedly increases the buffer capacity near neutrality . This is reflected in the flatter buffer curves. The samples which contained lower quantities of organic matter are most highly buffered at the extreme ranges of high acidity and basicity. This is indicated by typical sigmoid buffer curves. 3. The state of the decomposition of the organic matter in these samples indicates as has been shown by previous work that the buffering effect of the organic matter is associated with the lignin-humus fraction. 4. Additions of acid to the soil increased the solubility of the nutrient mineral elements. The increases in the solubilities were greatest in the samples that were low in organic matter. 5. Although liming increased the amount of soluble calcium in the soil, it did not decrease the solubility of phosphorus. The additions of lime decreased the solubility of potassium. The solubilities of iron and manganese were too low to be easily measured above pH 7.2 and in only one case above pH 5.0. 6. Additions of acid to the soil increased the solubility of potassium when the reaction was forced lower than pH 5.0. There was a greater increase in the solubility of potassium from the acid treatments in the samples that were lower in organic matter. 7. The solubilities of iron and manganese were increased from additions of acid. Manganese became much more soluble than iron from increased acidity and its solubility was more affected in the samples that were low in organic matter.

S-nitrosothiols (RSNOs) are an important group of nitric oxide (NO)-donating compounds with low toxicity and wide biomedical applications. In this paper, we, for the first time, demonstrate that the concentration of buffer remarkably affects the stability of RSNOs including naturally occurring S-nitrosoglutathione (GSNO) and synthetic S-nitroso-N-acetylpenicillamine (SNAP). For a solution with a high concentration of GSNO (e.g., 50 mM) and an initial near-neutral pH, the optimal buffer concentration is close to the GSNO concentration under our experimental conditions. A lower buffer concentration does not have adequate buffer capacity to resist the pH drop caused by GSNO decomposition. The decreased solution pH further accelerates GSNO decomposition because GSNO is most stable at near-neutral pH according to our density functional theory (DFT) calculations. A higher-than-optimal buffer concentration also reduces the GSNO stability because buffer ingredients including phosphate, Tris base, and HEPES consume NO/N2O3. In contrast to GSNO, the highest SNAP stability is obtained when the starting solution at a neutral pH does not contain buffer species, and the stability decreases as the buffer concentration increases. This is because SNAP is more stable at mildly acidic pH and the SNAP decomposition-induced pH drop stabilizes the donor. When the RSNO concentration is low (e.g., 1 mM), the buffer concentration also matters because any excess buffer accelerates the donor decomposition. Since the effect of buffer concentration was previously overlooked and suboptimal buffer concentrations were often used, this paper will aid in the formulation of RSNO solutions to obtain the maximum stability for prolonged storage and sustained NO release.

Scaling design effects on surface buffer (SB) insulated gate bipolar transistor (IGBT) is analyzed not only for power loss reduction but also for switching controllability and robustness using TCAD simulation. Although the scaling design improves turn-off loss and on-state voltage drop $\text{V}_{ce(sat)}$ trade-off due to injection enhancement (IE) effect, turn-on surge current is increased by the enhancement of negative gate capacitance due to thin gate oxide. Dual gate control improves turn-on switching controllability by hole current path control. Short circuit robustness is improved by the scaling design, because the saturation current is decreased with the scaling design due to pinch-off of the n-MOS channel. From these results, the scaling design is effective in improving the SB-IGBT characteristics including high robustness.

This paper presents the use of AZTS, a non-toxic and earth abundant material as buffer layer in CZTS solar cells due to its good lattice match. We have performed simulation on the experimentally fabricated AZTS/CZTS hetero-junction device by adding CZTS as back surface field (BSF) layer. In this work, first we have reconstructed the AZTS/CZTS experimentally designed solar cell then BSF layer is added to boost the solar cell performance in SCAPS simulator. Several parametersof AZTS buffer layer such as generation/recombination rate and doping concentration are varied during simulationto enhance the performance of investigated solar cells structures. It has been noticed that addition ofBSF layer increasesthe efficiency of AZTS/CZTS solar cell from 4.51% to 5.05% along with improvement of both Voc and FF.

We have studied the effects of proton irradiation on the AlGaN/GaN HEMTs with AlN buffer layer as well as conventional GaN buffer layer. It was found that a short time proton irradiation (~ 50 sec) can promote beneficial effects on device performances, which results in great reduction in the off-state leakage current and the gate leakage current without degrading the output current and transconductance. The pulsed I-V measurement demonstrated that both devices exhibit greatly improved current dispersion characteristics and, particularly, the device with AlN buffer layer shows stronger radiation hardness than that of the device with GaN buffer layer. These interesting results are believed to be due to the hydrogen passivation with thermal annealing effect during the proton irradiation. It is expected that the proper irradiation condition such as fluence, energy, and time is crucial to improve the device performances, rather than to deteriorate the performances.

This article reports a systematic study on the effects of the epitaxial layer structure on the electrical characteristics of AlGaN/GaN high electron mobility transistors (HEMTs) fabricated on freestanding GaN substrates. First, GaN-on-GaN HEMTs were fabricated comprising channel and buffer layers unintentionally doped with Fe atoms those were diffused from the substrate. Their electrical characteristics were compared with GaN-on-SiC HEMTs. The tradeoff relation between maximum drain current and the breakdown characteristics was improved in GaN-on-GaN devices than in GaN-on-SiC devices. A small current collapse was observed in GaN-on-GaN devices despite a high Fe density in the channel. This suggested an influence of Fe diffusion on the frequency dispersion to be comparatively limited. Second, GaN-on-GaN HEMTs were fabricated using a thin undoped channel layer grown on Fe-doped GaN substrate directly or through an Fe diffusion stopper layer. Without the stopper layer, the buffer leakage was significantly increased by reducing the channel thickness, and a 100-nm-thick channel device showed nonpinch-off characteristics. On the other hand, samples with the stopper layer exhibited no buffer leakage and a complete pinchoff up to 200 V. In addition, a sample with an intentional C doping to the buffer layer showed a relatively large current collapse, suggesting a major contribution of C-doping to the frequency dispersion of GaN-on-GaN HEMTs.

The hydrophobicity of natural rubber (NR) film provides it with a potential material for preparation of controlled drug delivery systems. The purpose of this study was to develop the NR/gelatin composite capsule shells for controlled drug release. The NR film and the NR/gelatin composite films, at the NR: gelatin ratio of 3:7, 4:6, 5:5, 6:4 and 7:3, were prepared. It was found that the composite films possessed higher strength and modulus, but lower elongation than the NR film. The smooth NR film absorbed water/aqueous media only to a small extent and hence scarcely eroded. Incorporation of gelatin resulted in the rough films, which were capable of absorbing more water/aqueous media and, therefore, eroding more than the NR film. The capsule shells were subsequently prepared from the NR: gelatin ratio of 6:4 composite film, contributing to its good mechanical properties and minimal erosion. Propranolol HCl was filled into the developed capsule shells. The drug was gradually released and reached the maxima within 8 and 4 h, in pH 1.2 and 6.8 buffer solutions, respectively. Thus, the NR/gelatin composite capsule shells were successfully prepared and able to control the drug release efficiently.

The residual stresses (RS) contribute to the integrity of the welded joint. In some cases, such as repaired dissimilar joints, this factor is crucial. The longitudinal (hoop) and transverse residual stresses of three chromium-molybdenum steel (A387 Grade 11)/austenitic steel (AISI 304) dissimilar welded repair mockups were measured in this study. The first and second repair mockups used ENiCrMo-3 and ENiCrFe-3 (conventional procedures), while the third repair mockup used ENi-1 as a buffer layer plus ENiCrFe-3. The contour method was used to measure longitudinal RS, and the slitting method was used to measure transverse RS. The buffer layer procedure resulted in lower longitudinal stresses at the interior regions of the repair than the other two procedures. The first, second, and third mockups showed transverse RS lower than the yield strength of the corresponding metals, with peak tensile stresses of 279, 113, and 230 MPa, respectively.

We report high-performance IGZO TFTs with MoAl/Cu/MoAl and MoMn/Cu/MoMn three-layer electrodes, where MoAl or MoMn alloy is used as the buffer layer. The multilayer electrode has good electrical properties and can effectively prevent the oxidation and diffusion of the middle Cu layer. In addition, the multilayer electrode can be etched in a PAN etchant solution and match the etching rate with Cu. Based on these MoAl/Cu/MoAl and MoMn/Cu/MoMn electrodes, vacuum-processed IGZO TFTs exhibit a turn-on voltage of 0 V, an on-off ratio of 10⁹, and a mobility of 10.7 cm² V⁻¹ s⁻¹ after annealing at 115 °C in N₂. Under the gate bias stress test, devices with MoMn electrodes, which exhibit a small threshold voltage shift, show better performance than those with MoAl electrodes. The presented studies may provide another option for the Cu buffer layer.

This paper reports investigation of failure mechanisms of GaN-on-Si power device under electrostatic discharge (ESD) stress using on-wafer transmission-line pulse (TLP) testing. Hot-hole injections under the gate and filament formation in the buffer layer are examined by monitoring the threshold voltage (Vth) and on-resistance (Ron) subjected to a floating gate or an off-state gate voltage. Distinct and continued degradation has been observed after the ESD stress is removed indicating a slow de-trapping process due to deep-level buffer traps. Finally, 2D device simulation is used to probe the physical insight into failure mechanisms.

Online fountain codes (OFC) have attracted much attention for their good intermediate performance, which is important for receivers with low-complexity requirement. However, low-complexity receivers generally have limited buffer size to store coded symbols that have not been fully decoded yet, as well as limited power budget for feedback transmissions. In this paper, we propose improved transmission schemes for online fountain codes to reduce the buffer occupancy and feedback transmissions. Firstly, we analyze the relationship between buffer occupancy and overhead as well as the relationship between recovery rate and overhead for online fountain codes. Motivated by the analysis, we propose the weighted online fountain codes (WOFC) which can adapt to various buffer sizes by adjusting the weight to control the probability that a coded symbol can be fully processed immediately, and analyze its performance. Then we further propose weighted online fountain codes with low feedback (WOFC-LF), which utilize the proposed analysis to estimate the recovery rate, and reduce feedback transmissions. Simulation results verify the effectiveness of the analysis for both OFC and WOFC, and demonstrate the superior performance of WOFC-LF with limited buffer size and feedback transmissions.

pH buffers of weak organic acids and bases are essential in capillary electrophoresis (CE) analyses, primarily when contactless conductivity detectors (C4D) are used. However, the preparation of a buffer with a known concentration of one component for use as a background electrolyte (BGE) in CE-C4D usually requires a pH adjustment to the desired value and an approximate calculation to estimate the concentration of the second component. This study developed software that allowed determining the concentration of one component when knowing the concentration of another component and the pH of the solution, taking into account the influence of ionic strength. The software was built in C# language with Windows Form interface on Microsoft Visual Studio. With the concentrations calculated from the developed software, the differences (|ΔpH|) between pH values of the obtained BGEs in practice and the desired values were smaller than 0.07, corresponding to the errors of less than 2%.

Current infrared thermal image sensors are mainly based on planar firm substrates, but the rigid form factor appears to restrain the versatility of their applications. For wearable health monitorin...

This paper describes the usage of shaders to make parallel operations by improving the CPU–GPU communication, using both rendering and compute shaders. When the number of spheres is large, the execution becomes slow and requires a lot of space to store particles. We parallelized the frozen method using an efficient inter-process GPU communication to reduce the operations required. We propose to handle two buffers, one for operations and the other for rendering. While the rendering buffer increases as the number of spheres is required, the operational buffer maintains its size and the number of operations is hold. Experimental results demonstrate that the proposed method shows up 100x throughput improvement over the sequential version. We define a configuration by a 4-tuple as input to the algorithm, and we found a pattern to choose better configurations.

Although super-resolution imaging offers an opportunity to visualize cellular structures and organelles at the nanoscale level, cellular heterogeneity and unpredictability still pose a significant challenge in the dynamic imaging of live cells. It is thus vital to develop better-performing and more photostable probes for long-term super-resolution imaging. Herein, we report a probe, LD-FG, for imaging lipid droplet (LD) dynamics using structured illumination microscopy (SIM). LD-FG allows wash-free imaging of LDs, owing to a hydrogen-bond sensitive fluorogenic response. The replacement of photobleached LD-FG by intact probe molecules outside the LDs ensures the long-time stability of the fluorescence imaging. With this buffering fluorogenic probe, fast and unpredictable dynamic processes of LDs can be visualized. Using this probe, two LD coalescence modes were discovered. The dynamic imaging also allowed us to propose a new model of LD maturation during adipocyte differentiation, i.e., a fast LD coalescence followed by a slow ripening step. The excellent performance of LD-FG makes the buffer strategy an effective method for designing fluorescent probes for cell dynamic imaging.

The aim of research was to investigate the theoretical and practical aspects of the buffer capacity of the recreational environment of the Carpathian region of Ukraine through the improvement of self-purification assessment on the example of natural-technogenic hydroecosystems. Studies of the self-purification process were carried out on the example of the right tributaries of the river Svicha in the Carpathian region, which are water intakes of wastewater from the oil and gas industry enterprise of Ivano-Frankivsk region. The main factors influencing the natural process of self-purification of natural watercourses are determined. As a result, the indicator of wastewater dilution intensity was improved with the substantiation of the proposed coefficients, which depend on the value of the river flow velocity and water temperature. A scale for assessing surface waters has been developed, that allows to determine the degree of natural self-purification of water from pollutants. Based on the results of the analysis of selected water samples, the pattern of self-purification of natural watercourses from oil products is obtained, which will allow to make forecast maps of the buffer capacity of the recreational environment of the Carpathian region. A regression analysis was performed, which proves the relationship between the content of petroleum products and the distance of their distribution from the source of pollution in the Lushchava River. Fisher's F-test was used to check the significance of the dependence. The reliability of the relationship between the indicators is confirmed by the coefficient of determination (D = r2), which is 0.96. Summarizing the results of the study the scale of estimation of natural self-purification of surface waters from pollutants depending on the calculated indicator of wastewater dilution intensity which’s criteria are the accounting for speed of a river flow and a temperature mode is offered. When establishing the range of n values, the average value of the calculated indicator of the intensity of wastewater dilution for the studied rivers, which is 4, was taken into account. As a result, the proposed scale of assessment of natural self-purification of surface waters allows to determine the degree of self-purification of the right tributaries of the river Svicha, which is necessary for further forecasting of water pollution in the Carpathian region.

The article proposes a method for modeling the processing of heterogeneous data in the buffer storage of routers. In contrast to the existing approaches, in the developed method, in the analytical description of the processes of functioning of buffer storage devices of routers under the influence of heterogeneous traffic of subscribers of a special-purpose communication network, the apparatus of the theory of cellular automata was used, which made it possible to take into account the probability of timely processing of data of all used priority levels of communication directions.As a result of the experiment carried out on the basis of a real special communication network, it was found that the developed method of modeling the processes of processing inhomogeneous data of buffer storage devices of routers makes it possible to increase the accuracy of determining the probability of timely delivery of priority information to subscribers of a special purpose communication network, in comparison with the existing standardized methods.

In the past few years, the all-solid lithium battery has attracted worldwide attentions, the ionic conductivity of some all-solid lithium-ion batteries has reached 10−3–10−2 S/cm, indicating that the transport of lithium ions in solid electrolytes is no longer a major problem. However, some interface issues become research hotspots. Examples of these interfacial issues include the electrochemical decomposition reaction at the electrode-electrolyte interface; the low effective contact area between the solid electrolyte and the electrode etc. In order to solve the issues, researchers have pursued many different approaches. The addition of a buffer layer between the electrode and the solid electrolyte has been at the center of this endeavor. In this review paper, we provide a systematic summarization of the problems on the electrode-solid electrolyte interface and detailed reflection on the latest works of buffer-based therapies, and the review will end with a personal perspective on the improvement of buffer-based therapies.

Hydrazones derived from pyridoxal 5'-phosphate and 4-hydroxybenzohydrazide, 3-hydroxynaphthohydrazide, and L-tyrosine hydrazide have been synthesized. The complexation of La3+, Ce3+, Eu3+, and Gd3+ ions with these hydrazones in a neutral aqueous solution (0.05 M Tris–HCl buffer, pH 7.2) has been studied. The most probable stoichiometric composition and apparent stability constants of the complexes at a fixed pH value have been determined. The possibility of using pyridoxal-5-phosphate hydrazones to create fluorescent probes for bioimaging or contrasting agents for MRI has been considered.

In this paper, SnO2 nanoparticles were designed and synthesized by the hydrothermal method. It was confined to a jute fiber cellulose carbon (JFCC) framework, which was equivalent to a biomass carbon buffer layer wrapped around SnO2 nanoparticles. The combination of SnO2 nanoparticles and the amorphous carbon buffer layer alleviated the volume expansion effect of SnO2 to a certain extent, shortened the lithium-ion diffusion path, and improved the conductivity. At 0.2C, the discharge specific capacity of the composite (SnO2@JFCC) was finally stabilized at 1298.5 mAh g−1 after 100 cycles. The discharge specific capacity was stabilized at 1090.3 mAh g−1 for 1000 cycles at 2C, which further showed the good synergy between SnO2 nanoparticles and JFCC and exhibited excellent lithium storage performance.

The purpose of this study is the efficiency improvement of the Sb2Se3 solar cells. In this study, an experimental Sb2Se3 solar cell (glass/Mo/MoSe2/Sb2Se3/CdS/ZnO/ZnO:Al/Ag) with an efficiency record of 9.2% has been simulated. Absorber/buffer interface engineering plays a significant role in enhancing the efficiency of Sb2Se3 solar cells. To achieve this purpose, two approaches have been considered: first, adding sulfur to Sb2Se3 absorber, and second, using an alternative buffer with a wider bandgap instead of conventional CdS buffer. The effects of various x = Se/(S + Se) ratios of Sb2(S1−xSex)3 absorber layer on the photovoltaic performance were investigated. For Sb2(S,Se)3/CdS solar cell, optimum Se/(S + Se) mole fraction of 0.6 < x < 0.8 leads to improved efficiency. Also, ZnO1−ySy buffer layer was applied to replace the conventional CdS buffer layer of Sb2Se3 solar cells to reduce parasitic absorption and improve the short-circuit current density (Jsc). Bandgap for ZnO1−ySy semiconductor is higher than CdS. So, this leads to improved external quantum efficiency at short wavelengths. Optimization of band alignment through ZnO1−ySy buffer layer reduces interface carrier recombination and improves open-circuit voltage (Voc). The band alignment at the Sb2(S1−xSex)3/ZnO1−ySy interface is optimized by adjusting the selenium-to-sulfur ratio in the absorber layer and sulfur-to-oxygen ratio in the buffer layer. This work reveals that the most suitable interface for Sb2(S1−xSex)3/ZnO1−ySy heterojunction is formed when sulfur mole fractions ranging 0.5–0.6 in the Zn(O,S) buffer layer and 0.1–0.2 in the Sb2(S,Se)3 absorber layer. The results show that the efficiency improves from 9.2% to 15.65%, which represents a 70% improvement compared with the conventional Sb2Se3/CdS solar cell.

Buffer/backfill materials for radioactive waste disposal sites consist of pure bentonite or bentonite-rock mixtures. In this study, the batch test method was used to obtain the sorption characteristics of important radionuclides such as Cs, Sr and Co on buffer/backfill materials; i. e., mixing Wyoming MX-80 bentonite or local Taiwanese Zhi-Shin bentonite with possible host rock (argillite and granite) in different proportions (0∼100%). The distribution coefficients (Kd) for Cs, Sr and Co were obtained from the experiments. The distribution coefficient for the bentonite-rock mixtures were found, with more than 50% of mixing proportion of bentonite to argillite or granite, to have very similar values to that of pure bentonite. Furthermore, it was clearly found that the sorption of Cs, Sr and Co to bentonite-rock mixtures is decreased as ionic strength of the liquid phase is increased from 0.001M to 1M for NaCl solutions. According to the experimental results, in synthetic groundwater, it is quite convenient and helpful to assess the distribution coefficients (Kd) of Cs, Sr and Co for buffer/backfill materials using batch sorption experiments with bentonite-rock mixtures of fixed mixing proportions.

The effect of thymine as a buffer layer has been examined on the performance of organic photodetectors. As the decreasing dark current with incorporation of buffer layer, a significant increase in ...

Incorporation of a magnesium oxide (MgO) cathode buffer layer fabricated by a reaction of thermally-deposited magnesium with molybdenum oxide in semi-transparent vacuum-processed Schottky and solut...

Within the multi-barrier system for high-level waste disposal, the technological gap formed by combined buffer material block becomes the weak part of buffer layer. In this paper, Gaomiaozi bentonite buffer material with technological gap was studied, the heat transfer induced by liquid water flow and water vapor was embedded into the energy conservation equation. Based on the Barcelona basic model, the coupled thermo-hydro-mechanical model of unsaturated bentonite was established by analyzing the swelling process of bentonite block and the compression process of joint material. The China-Mock-up test was adopted to compare the numerical calculation results with the test results so as to verify the rationality of the proposed model. On this basis, the effect of joint self-healing on dry density, thermal conductivity and permeability coefficient of buffer material was further analyzed. The results show that, with bentonite hydrating and swelling, the joint material gradually increases in dry density, and exhibits comparatively uniform hydraulic and thermal conductivity properties as compacted bentonite block. As a result, the buffer material gradually shifts to homogenization due to the coordinated deformation.

In ferroelectric-based integrated devices, there are usually buffer layers between ferroelectric films and semiconductor substrates. Here, Bix%FeO3-δ (x = 95, 100, and 105) (BFOx) films are prepared directly on n-Si substrates by the sol-gel method, and the variation of the hysteresis loops with Bi content and heat treatment is investigated. With the help of the dielectric measurement and the composition analysis, a PN heterojunction is believed to exist at the BFOx/Si interface. The Bi/Fe ratio determines not only the type and concentration of charged defects in the films but also the height of the interface barrier and its binding effect on mobile charges. Furthermore, the distribution and the migration of charges can be regulated reversibly by heat treatment. This work reveals the interaction between ferroelectric films and semiconductor substrates, providing an important reference for the design and application of ferroelectric/semiconductor heterostructures.

We fabricated a photodetector device consisting of ITO/NiOx/Perovskite/PC60BM/BCP/Ag. The NiOx layer was deposited using the sol–gel and combustion processes. Combustion-processed NiOx films have advantages such as low annealing temperature, improved perovskite film quality, and better photodetector performance compared to the sol–gel processed NiOx film. The improved film quality, improved charge transfer, and reduced dark current of the device using combustion-processed NiOx film were investigated by measuring the current–voltage characteristics, transient photocurrent, and impedance analysis. The photodetector using the combustion-processed NiOx achieved a high detectivity of 1.20×1013 Jones and bandwidth of over 2 MHz at -0.1 V and 550 nm.

This paper proposes a new model of the cylindrical pin coupler and buffer system and then a more accurate train dynamic model to investigate the heavy-haul locomotive dynamic performance and runnin...