Resistance Values Research Articles

Measurement of stress characteristics in flexible multi-thin-film substrates using tomography common optical path interferometry

Flexible displays are lightweight, thin, flexible, and impact-resistant, making them a major trend in the display industry. However, their short lifespan is a significant challenge. Thus, improving process parameters and extending product life through advanced measurement technology is crucial. Therefore, this study proposes using tomography common optical path interferometry (TCOPI) to measure and analyze the tomography stress characteristics of multi-thin-film flexible substrates in the folding direction. For polyethylene terephthalate (PET) and polyimide (PI), three thicknesses of indium tin oxide (ITO) were coated on the PET, graphene/PET, and graphene/PI flexible film substrates, and an automatic sliding-folding test platform was used to fold each flexible film substrate. Moreover, this study used TCOPI to measure and analyze the change in residual stress and the sheet resistance of the samples before and after folding. Additionally, this study conducted inward and outward folding tests on graphene/PET/graphene and graphene/PI/graphene substrates to analyze tomographic stress and sheet resistance in the folding direction. After 11,000 folding tests, the graphene/PET/graphene sample exhibited smaller stress and sheet resistance change rates compared to the graphene/PI/graphene sample, as measured by TCOPI. Consequently, the graphene/PET/graphene sample demonstrated better resistance to folding stress in this batch manufacturing process. Specifically, for the graphene layer of the graphene/PET/graphene sample, the minimum absolute value of the stress change rate before and after folding reached 5%. At the same time, the minimum sheet resistance value change rate was 8%. Based on the tomography stress measurements, suggestions for fine-tuning process parameters are provided to improve the flexible film substrate’s folding endurance.

Evaluation of the backflashover performance of 150 kV and 400 kV double-circuit overhead transmission lines as affected by lightning attachment models and peak current distributions

The evaluation of the backflashover performance of overhead transmission lines requires the adoption of a lightning attachment model and a peak current distribution. These affect the estimated backflashover rate, BFR, of the lines. The present study aims to quantify the influence of lightning attachment model and peak current distribution on the BFR of double-circuit overhead lines. This is achieved by evaluating typical 150 kV and 400 kV lines. ATP-EMTP simulations are conducted to obtain the critical currents causing backflashover of line insulation. Then, the critical currents are used in lightning incidence computations to obtain BFR. The influencing parameters taken into account in this work are the low current and low frequency tower ground resistance, the location of lightning strike to the shield wire along the span, and the AC voltage phase angle, all affecting the critical backflashover current. Several lightning attachment models and peak current distributions are evaluated. Their influence on BFR is found to be considerable, especially for lower tower ground resistance values. The lightning peak current distributions yield more pronounced effects on BFR. The results of this study stress the need for computing BFR using a more accurate expression than the simplified one based on CIGRE TB 63.

An In Silico Modelling Approach to Predict Hemodynamic Outcomes in Diabetic and Hypertensive Kidney Disease.

Early diagnosis of kidney disease remains an unmet clinical challenge, preventing timely and effective intervention. Diabetes and hypertension are two main causes of kidney disease, can often appear together, and can only be distinguished by invasive biopsy. In this study, we developed a modelling approach to simulate blood velocity, volumetric flow rate, and pressure wave propagation in arterial networks of ageing, diabetic, and hypertensive virtual populations. The model was validated by comparing our predictions for pressure, volumetric flow rate and waveform-derived indexes with in vivo data on ageing populations from the literature. The model simulated the effects of kidney disease, and was calibrated to align quantitatively with in vivo data on diabetic and hypertensive nephropathy from the literature. Our study identified some potential biomarkers extracted from renal blood flow rate and flow pulsatility. For typical patient age groups, resistive index values were 0.69 (SD 0.05) and 0.74 (SD 0.02) in the early and severe stages of diabetic nephropathy, respectively. Similar trends were observed in the same stages of hypertensive nephropathy, with a range from 0.65 (SD 0.07) to 0.73 (SD 0.05), respectively. Mean renal blood flow rate through a single diseased kidney ranged from 329 (SD 40, early) to 317 (SD 38, severe) ml/min in diabetic nephropathy and 443 (SD 54, early) to 388 (SD 47, severe) ml/min in hypertensive nephropathy, showing potential as a biomarker for early diagnosis of kidney disease. This modelling approach demonstrated its potential application in informing biomarker identification and facilitating the setup of clinical trials.

Fracture Resistance and Push-Out Bond Strength of Three Post Types in the Restoration of Anterior Primary Teeth - A In Vitro study.

Restoration fractures and displacement are the two main causes of failure after the rehabilitation of severely worn primary anterior teeth. Compare the effect of three post types on the fracture and push-out bond strength. Sixty undamaged maxillary anterior primary teeth were allocated into three groups according to post type: (I) Tetric N Ceram composite post, (II) prefabricated glass fiber post, and (III) high viscous glass ionomer post. Each group was further subdivided into two sub-groups depending on the test used: fracture resistance test and push-out bond strength test. The all specimens were mounted in acrylic resin blocks and tested using a universal testing machine. The fracture and failure mode were determined by a stereomicroscope inspection of all the specimens. Data were analyzed by one-way analysis of variance (ANOVA) and the Bonferroni post hoc test (P < 0.05). There was a statistically significant difference between fracture resistance and push-out bond strength values for the experimental groups (P < 0.05). The most significant fracture resistance value was in Group II and core/post fracture (restorable fracture) was the most obvious fracture in the three groups with the highest percentage in Group I. The most significant push-out bond strength value was in Group I and adhesive failure between dentin and luting cement/post was the most common type in the groups. The fracture resistance and push-out bond strength were affected by the type of post (P = 0.000). Prefabricated glass fiber posts showed the highest fracture resistance in this study. However, Tetric N Ceram composite posts had the most restorable fracture. Tetric N Ceram composite posts had the highest bond strength with adhesive failure mode.

Precision Temperature Measurement and Error Analysis for Three-Wire PT100 Resistance Temperature Detector (RTD) using LTSpice

This work focuses on temperature measurement and error extraction for Resistance Temperature Dependence (RTD). RTD is notable for its high accuracy, linearity, and stability. However, obtaining a system error of less than unity in RTD is critical. A platinum RTD is an ideal option if the system requires an accuracy level over a wide temperature range (-200°C to +800°C). Therefore, this work investigated the temperature measurement and extraction of error in RTD by simulating a three-wired PT100 RTD using LTSpice. The analytical calculations were also developed to demonstrate the RTD’s error and were compared with the simulation results for verification purposes. It was discovered that the optimized temperature measurement and percentage errors are 0.01°C and 0.004% respectively. The values of Vc, Sense Resistor (RSENSE), and Reference Resistor (RREF) for the excitation current were found to be significant to maximize the output voltage and mean absolute error (MAE) on the test set, offering insights into the model's overall fit, average deviation, and sensitivity to outliers. Results reveal strong correlations between PV module temperature, irradiance, and AC power generated.

Precision Temperature Measurement and Error Analysis for Three-Wire PT100 Resistance Temperature Detector (RTD) using LTSpice

This work focuses on temperature measurement and error extraction for Resistance Temperature Dependence (RTD). RTD is notable for its high accuracy, linearity, and stability. However, obtaining a system error of less than unity in RTD is critical. A platinum RTD is an ideal option if the system requires an accuracy level over a wide temperature range (-200°C to +800°C). Therefore, this work investigated the temperature measurement and extraction of error in RTD by simulating a three-wired PT100 RTD using LTSpice. The analytical calculations were also developed to demonstrate the RTD’s error and were compared with the simulation results for verification purposes. It was discovered that the optimized temperature measurement and percentage errors are 0.01°C and 0.004% respectively. The values of Vc, Sense Resistor (RSENSE), and Reference Resistor (RREF) for the excitation current were found to be significant to maximize the output voltage and mean absolute error (MAE) on the test set, offering insights into the model's overall fit, average deviation, and sensitivity to outliers. Results reveal strong correlations between PV module temperature, irradiance, and AC power generated.

Influence of Apparatus Scale on Geogrid Monotonic and Cyclic/Post-Cyclic Pullout Behavior in Cohesive Soils

Geosynthetics have increasingly been applied to geotechnical engineering works due to their numerous advantages, including cost-effectiveness and their significant role in sustainable development. When geosynthetics are used as reinforcement in earth structures, such as embankments, retaining walls and bridge abutments, soil–geosynthetic interface shear behavior is a critical parameter involved in the design. This paper presents a series of monotonic and cyclic/post-cyclic pullout tests carried out to examine the apparatus scale effect on the pullout response of a geogrid embedded in two different soils. To assess the small-scale equipment feasibility, comparisons were made between pullout test parameters derived from small- and large-scale equipment. The test results indicate that, under a low confining stress of 25 kPa, using a smaller-sized apparatus results in lower values of geogrid pullout resistance and maximum mobilized shear stress, but higher values of confined tensile stiffness at low strains. On the other hand, as the confining stress increases (i.e., 50 kPa and 100 kPa), the difference between the results becomes less significant and similar trends are observed regardless of the equipment type. Adopting small-scale equipment enables obtaining soil–reinforcement interaction parameters using test procedures that are less time-consuming than those associated with large-scale pullout tests. However, proper scale effect correction factors may be considered for more consistent estimates of the interface strength parameters under low normal stress values.

Influence of multi-doping (Zn and Sn) on the optical, and electrical properties of spray-deposited CdO thin films

This investigation has been focused on the spray-deposited pure cadmium oxide (CdO) thin films and also doped with zinc (Zn) and tin (Sn), as a transparent conducting oxide for optoelectronic applications. By varying the concentration of Sn (0–2%) into CdO, the microstructural, morphological, and optoelectronic properties were investigated. XRD spectra confirmed the polycrystalline cubic structure of the pure, doped, and co-doped CdO films. SEM investigation reveals the crack-free homogeneous cauliflowers-like morphology of the fabricated thin films. The existence of elemental compositions such as Cd, Zn, Sn, and O in the prepared films was confirmed by EDS analysis. All of the doped and co-doped CdO films showed good transparency in the visible range. Moreover, a slight increment has been found in the optical band gap from 2.43 eV to 2.50 eV with increasing Sn concentration, which can be explained by the Burstein-Moss phenomena. A decrement of Urbach energy was noted for an increased concentration of Sn. Besides, Zn and Sn (1 %) co-doped films exhibited the lowest electrical resistivity value 4.09×10−4 Ω-cm among other doped compositions. However, the addition of Zn and Sn into CdO thin films enhanced the optoelectronic properties.

Influence of Different Ions on Pulse Electrodeposition of CaCO3 Scales in the Simulated Seawater.

In the circulating water system of coastal power plants, various kinds of ions have a great influence on the formation and growth of CaCO3 scales. This paper focuses on investigating the influence of existing ions on the pulse electrodeposition behaviors of CaCO3 scales. Different concentrations of ions, such as Fe3+, Mg2+, PO43- and SiO32-, are introduced to simulate the actual seawater environment, and their influence on the CaCO3 scale deposition behaviors is assessed by linear sweep voltammetry, chronoamperometry, and electrochemical impedance spectroscopy tests. The surface coverage of the CaCO3 scale layer is evaluated through the residual current density and polarization resistance values, while the crystal structure and surface compactness of the layer are confirmed by the scanning electron microscope and X-ray diffractometer tests. Results indicate that high concentrations of Mg2+, Fe3+, and PO43- ions have the most significant inhibitory effect on the pulse electrodeposition of CaCO3 scales, among which the inhibition effect of Mg2+ ions is mainly reflected in the change of crystal morphology of CaCO3, that is, the crystallization growth process is inhibited. The inhibition effect of PO43- ions is mainly reflected in the gradually reduced coverage and density of CaCO3 crystals on the electrode surface, suggesting that the crystallization nucleation process is inhibited, while Fe3+ ions have a certain inhibition effect on both the crystallization nucleation and growth processes. Furthermore, lower concentrations of SiO32- ions also display a significant inhibition effect on the crystallization nucleation and growth process, and the inhibition effect weakens with increased concentration. This study provides a theoretical basis for exploring the removal of ions in the industrial water softening field.

Non-linear MHD investigations of high-confinement regimes without type-I ELMs in ASDEX Upgrade and JT-60SA

Abstract Large edge localised modes (ELMs) would cause an unacceptable reduction of material lifetime in future large tokamaks due to the significant amount of energy expelled from the magnetically confined region towards the plasma facing components. Thoroughly validated modelling of regimes devoid of large ELMs is crucial as it may then provide predictive insights prior to tokamak operation and design. This paper describes recent efforts pursued with the non-linear extended MHD code JOREK in the modelling of three scenarios without large ELMs: quiescent H-mode (QH-mode), quasi-continuous exhaust regime (QCE regime), and the enhanced D-alpha H-mode (EDA H-mode). For each of these regimes, the non-linear dynamics observed in the simulations are detailed and compared to experimental observations of the underlying instabilities of each regime (edge harmonic oscillation for QH-mode, small ELMs for QCE regime, and quasi-coherent mode for EDA H-mode). For QH-mode, the kink-peeling mode is found to govern the dynamics and a transition to a large ELM is obtained above the same density threshold as in the modelled experiment. For the QCE regime and EDA H-mode, resistive peeling-ballooning modes dominate and pedestal fluctuation amplitudes correspond well to experimental observations. The dominant mechanisms for the excitation and suppression of these instabilities is presented and their influence on simulation dynamics is shown. Finally, predictive simulations of edge instabilities at different values of plasma resistivity in a 4.60 MA scenario with low edge safety factor in JT-60SA are presented.

Facile route for processing natural polymers for the formulation of new low-cost hydrophobic protective hybrid coatings for carbon steel in petroleum industry

AbstractThis research helps with the creation, assessment, and characterization of a new hybrid protective coating for carbon steel alloy in acid conditions. The findings of this study will be useful for both chemical and petrochemical companies as well as scientists. This study aims to protect C-steel in acid pickling solution 1.0M HCl and formulate new hydrophobic protective hybrid organic–inorganic coatings from biopolymers chitosan and plant resin guar gum. Eight coating samples of chitosan in the absence and the presence of guar gum, silica and two heterocyclic compounds are prepared at feasible operational conditions using hot melt method. The aiding additives improved compatibility between coating constituents as confirmed by using different methods of analysis. This new processing approach has addressed the problems of using chitosan in corrosion control such as solubility in acid media and low mechanical strength. Coating samples of chitosan and its composites with the heterocyclic compounds (2-Hydrazinyl-6-methyl-4, 5-dihydro pyrimidine-4-on) or (2-Hydrazinyl-6-phenyl-4, 5-dihydro pyrimidine-4-on) are potent biocides. Coating shifts corrosion potential of carbon steel by 30 mV to more noble direction relative to the active potential 520 mV of bare carbon steel surface. Impedance and polarization measurements indicate that coating samples protect metal surface as mixed-type inhibitor by adsorption mechanism. There is a good agreement between percentages protection %P of coating calculated using the values of charge transfer resistance, Rct, and corrosion current density, icorr. All %P values are above 99% for all coating samples. Guar gum plant resin increases gloss of the coating film. Silica fills the pores in the polymeric film and increases the stuffiness of the polymeric coating film by modifying the particle size. All coated samples have high contact angle ranging from 150° to 165° indicating low wettability and high hydrophobicity of coating film on the metal surface.

Pengaruh Angin Terhadap Tata Letak dan Jumlah Sekrup Konstruksi Baja Ringan Berdasarkan SNI-7971- 2013

Light weight steel material has experienced rapid development in the construction. However, there are still many costruction failures on light weight steel, resulting in cost loss. The failure of light steel structures often occurs at the connections. The connection tool on milld steel is usually using a self-drilling screw. The research location is at Aceh One Stop Integrated Service and Investment Service Building (DPMPTSP) Aceh. The problem in this study is the placement and number of screws on the lightweight steel roof structure in the field which is carried out for each member according to the code, and the effect of wind load on the placement and number of screws on the lightweight steel roof structure. This study aims to determine the effect of the placement and number of screws on the lightweight steel roof structure. The scope of this research of problems including the placement and number of screws on the lightweight steel roof structure. The standars used in the design of light steel structures in this study is SNI 7971 2013 and the loading planning standars using SNI 03 1727 1989. Calculation steps using the LRFD method for steel structure design regulated in SNI 03 1729 2002. Based on the results, it is obtained that the number and placement of the screws in the field are different from those obtained in the calculation. From the calculations, it is obtained from the recapitulation, dead loads with a maximum value of 123.07 kg, live loads with a maximum load of 30.1 6 kg, and for compressed air and suction loads with a maximum load of 180 kg. the maximum design force value is 1241.33 kg and the screws bearing resistance value is 256.752 kg. the number of screws is obtained where the the value of the design force is divided by the value of the bearing resistance, on each member obtained 1screw, 2 screws, 3 screws, 4 screws, and 5 screws. Whilst it is found for each member in the field using 3 screws.

Influence of 700 KeV O3+ ion implantation on current transport properties of Cr/p-GaN SBD’s

In the present study we show a detailed investigation into the influence of 700 KeV O3+ ion implantation in Cr/p-GaN SBDs on electrical characteristics / current transport properties. Also the damage events along the trajectory of the ion beam were quantitatively estimated through SRIM and TRIM simulations. The Current-voltage (I-V) characteristics were analyzed using different methods such as Cheung and Cheung's method and Norde’s method to obtain different electrical parameters. The values of n and ϕB decrease up to a fluence of 1 × 1014 ions cm−2, and show a fractional increase at a fluence of 1 × 1015 ions cm−2. Further, a drastic increase in values of series resistance (RS ) of SBDs with an increase in fluence was observed. In the forward-bias voltage regions, the Cr/p-GaN SBDs conduction mechanism shows an increasingly ohmic behavior with an increase in fluence, which may be attributed to thermally generated carriers. At low voltage, the reverse current conduction mechanism is due to Poole-Frenkel emission. For the high voltage region, Schottky emission mechanism becomes more prominent. The changes in electrical parameters are closely related to the defect and damage profiles estimated through SRIM/TRIM simulations, which are strongly dependent on the dose of the 700 KeV O3+ ion implantation. Additionally, we found that at high doses, the charge transport mechanism changes, with additional defects affecting not only the thermionic emission mechanism but also various current transport mechanisms.

Aza-BODIPY-based logic gate chemosensors and their applications

Dimethylaniline-substituted aza-BODIPY dyes (DA, DM, DP) were designed and synthesized aiming for ion detection. The Zn2+ recognition ability was found in all compounds and the binding mechanism was possibly via dimethylaniline sites linked to the aza-BODIPY core. Upon Zn2+ addition, the new absorption band and the color change occurred due to the altered charge transfer of the adducts. The custom-made colorimeter was successfully integrated into the dye’s application, demonstrating a good linear relationship between resistance values and Zn2+ concentration. The chromophore test strips were fabricated and exhibited distinct color changes upon aqueous Zn2+ exposure. The compound DA also exhibits logical behavior with DA-Zn2+-Cu2+ system. In terms of environmental hazards, the compounds exhibited no adverse effect on Pseudomonas putida at the concentration level of 0.2 mg/mL. These findings indicated that all synthesized aza-BODIPYs might be suitable for chemosensor probes for Zn2+ detection with possibly low environmental risk.

Mismatch repair deficiency and abnormal p53 expression has significant predictive value for progesterone resistance and endometrial tumorigenesis in patients with endometrial atypical hyperplasia receiving fertility-preserving treatment

ObjectiveThis study aimed to evaluate the prognostic ability of mismatch repair deficiency (MMR-d) and abnormal p53 expression (p53abn) in patients with endometrial atypical hyperplasia (EAH) who underwent fertility-preserving treatment. MethodsThis retrospective study evaluated 51 patients with EAH who underwent fertility-sparing treatment. Endometrial biopsy specimens obtained before hormone therapy were collected and used for immunohistochemical staining for MMR and p53 proteins. Response, relapse, and progression rates were assessed based on age, body mass index, diabetes, polycystic ovary syndrome, reproductive history, MMR status, and p53 status. ResultsOverall, 11/51 (21.6%) patients had loss of MMR proteins and 6/51 (11.8%) had p53abn. Patients with MMR-d had lower complete response (CR) rates than those with normal staining patients at 12 months after initial treatment (p = 0.049). Patients with MMR-d had significantly higher relapse rates than those with MMR-p at the 1-year follow-ups after achieving CR (p = 0.035). Moreover, patients with MMR-d had a higher incidence of disease progression at 2, 3, and 4 years after fertility-sparing treatment (p = 0.001, p = 0.01 and p = 0.035, respectively). Patients with p53abn had higher relapse rates than those with p53wt at the 1- and 2-year follow-ups after achieving CR (p = 0.047 and p = 0.036, respectively). Moreover, patients with p53abn had a higher incidence of disease progression at 3 and 4 years after fertility-sparing treatment (p = 0.02 and p = 0.049, respectively). ConclusionsEAH patients with MMR-d and p53abn have a significantly higher risk of disease relapse and progression. Thus, MMR-d and p53abn may be used as predictive biomarkers of progestin resistance and endometrial tumorigenesis in EAH.

Volatile memory characteristics of CMOS-compatible HZO ferroelectric layer for reservoir computing

Recently, ferroelectric memory utilizing hafnium oxide has emerged as an attractive option compared to existing memory technologies, primarily due to its scalability and energy-efficient advantages. Among them, hafnium zirconium oxide (HZO) is examined for its short-term memory characteristics to achieve a reservoir computing system known to exhibit remarkable polarization properties, being able to switch between distinct polarization states under the influence of an electric field. These unique properties are of utmost importance in ferroelectric memory applications, where they play a pivotal role in the storage and retrieval of binary data. In this study, we identify and experiment with the electrical characteristics of a ferroelectric tunnel junction (FTJ) device with a metal-ferroelectric-semiconductor (MFS) structure using TiN as the top electrode and HZO as the ferroelectric layer. Moreover, we assess the performance of the device by evaluating its maximum 2Pr (remnant polarization) and tunneling electro resistance (TER) values in different conditions of cell area. Furthermore, we analyze and show short-term memory (STM) characteristics and synaptic properties with 5 cycles of potentiation and depression under conditions of stable dynamic range by coordinating identical and incremental pulses. In the case of incremental pulses (> 95%), the MNIST pattern recognition accuracy is higher than in the case of identical pulses (> 94%). Through a sequence of procedures, the synaptic characteristics of FTJs are confirmed to assess their suitability for use as an artificial synaptic device.

Study on the phosphate/electrophoretic composite coatings on Mg alloy: The effect of phosphate conversion films on adhesion strength and corrosion resistance

Electrophoretic (EP) coating is one of the most useful methods for corrosion protection of Mg alloys. The phosphate conversion film (P film) is required before electrophoresis to improve the adhesion strength and corrosion resistance. In this work, the P films with different thickness prepared on the AZ31 Mg alloy by controlling the phosphating time. The adhesion strength and corrosion resistance of the P films and the corresponding electrophoretic composite (P-EP) coatings were investigated by pull-off tests and electrochemical impedance spectroscopy (EIS). The results show that the thickness of the P film is an important factor affecting the comprehensive performance of P-EP coatings, that is, with the increase of P film thickness, the corrosion resistance of P films increases, but the adhesion of P-EP decreases. The P-EP coating exhibits good adhesion but poor corrosion resistance when the P film is thin, and the P-EP coating with the P film thickness of about 3.5 μm shows the best comprehensive performance at phosphating time of 10 min. Compared with the EP coating without phosphating pretreatment, the adhesion strength of the optimum P-EP coating increases by 50 % and the resistance value increases by two orders of magnitude.

The figure of merit improvement of (Sn, Co)–ZnO sprayed thin films for optoelectronic applications

Nanocrystalline zinc oxide (ZnO) has garnered significant attention from researchers and industries due to its superior properties as an optoelectronic material, particularly in solar cells as a transparent electrode. Doping, especially with tin (Sn) and co-doping with tin and cobalt (Co), can refine its optoelectronic properties. In this manuscript, we report on the optoelectronic properties of undoped ZnO thin films, as well as those doped with Sn and/or Co, elaborated using a simple chemical pneumatic spray pyrolysis method on glass substrates. A 1 % Sn doping concentration was used, with Co doping concentrations of 0 %, 0.5 %, and 1 %. The effects of Sn and/or Co doping concentration on the structure, morphology, optical, and electrical properties of nanocrystalline ZnO were studied using X-ray diffractometer (XRD), Raman spectroscopy, Field emission scanning electron microscopy (FESEM), UV–Vis–NIR spectroscopy and Hall effect measurements. All the films studied exhibit wurtzite ZnO structures with a predominant (002) orientation and no secondary phase, as confirmed by X-ray diffraction (XRD) analysis. The Raman spectroscopy also reveals the presence of a wurtzite structure in all the films. The FESEM images reveal the kind and concentration of the dopants significantly influenced the surface morphology of the films. The elemental analysis with energy dispersive X-ray analysis (EDS) analysis successfully detected the doping of Sn and Co. The analysis of UV–Vis spectroscopy provide that the optical band gap for the undoped ZnO film is 3.25 eV. This band gap increases upon doping and co-doping, reaching a peak value of 3.30 eV for the Sn:Co (1 %:0.5 %) co-doped ZnO film. The ZnO film shows an improvement in the electrical resistivity upon doping and co-doping with low resistivity value of 1.95 × 10−2 Ω cm for the film (1%Sn, 0.5 % Co)–ZnO. The highest figure of merit (FOM) achieved is 1.41 × 10−4 Ω−1 for a ZnO thin film co-doped with (1 % Sn, 0.5 % Co). The existence of (1 % Sn, 0.5 % Co) film with improved optical gap, low electrical resistivity and high FOM supports its use in transparent conductive oxide applications.

Effect of preparation design on the fracture resistance and fracture patterns of 3D printed one-piece endodontic crowns

Statement of problemThe impact of various preparation designs on the fracture resistance and fracture type of mandibular premolars restored with 3 dimensionally (3D) printed, 1-piece endodontic crowns remains unclear. PurposeThe purpose of this study was to investigate the effect of different preparation designs on the fracture resistance and fracture patterns of mandibular premolars restored with 3D printed 1-piece endodontic crowns after thermal aging. Material and methodsForty-five freshly extracted mandibular premolars received 3 different preparation designs: with at least 2 intact cuspal walls (2CW), with only 1 intact cuspal wall (1CW), and no cuspal wall present (NoCW). One-piece endodontic crowns were designed by using a computer-aided design (CAD) software program, 3D printed, cemented to the prepared teeth with self-adhesive resin cement, and thermocycled between 5 °C and 55 °C in artificial saliva. Subsequently, all specimens were subjected to a fracture test. The results were statistically analyzed using 1-way ANOVA (α=.05), and fracture types of all specimens were examined using a light microscope. ResultsThe analysis of fracture resistance values across separate designs revealed no statistically significant differences (P>.05). Mean fracture resistance values were 724.5 N in 2CW, 713 N in 1CW, and 861 N in NoCW. In 2CW and 1CW, the 1-piece endodontic crowns mostly displayed Type III fractures, whereas those in NoCW exhibited a combination of Type II and Type III fractures. ConclusionsThe mandibular premolar 1-piece endodontic crowns tested in this study exhibited similar fracture resistance and type of fracture with different preparation designs.

EVALUATING ACETONE AND METHANOL FOR ELECTROPHORETIC DEPOSITION OF SS 316L COATED WITH HYDROXYAPATITE/MULTIWALLED CARBON NANOTUBES DENTAL IMPLANTS: A FOCUS ON CORROSION RESISTANCE

Dental implants offer a reliable solution for replacing damaged tooth roots. This research investigates the comparative performance of acetone and methanol as suspension media in the fabrication of stainless steel type 316L-based dental implants using the Electrophoretic Deposition (EPD) method, a technique known for its simplicity and cost-effectiveness. Voltage variations of 20V, 30V, and 40V were applied to both acetone and methanol suspensions for a duration of 20 minutes. The morphology of the Hydroxyapatite/Multiwalled Carbon Nanotube (HA/MWCNT) coatings was meticulously characterized using Scanning Electron Microscopy (SEM). Corrosion resistance was evaluated through Potentiodynamic Polarization (PDP) and Electrochemical Impedance Spectroscopy (EIS) techniques. Remarkably, at 30V, a homogeneous and crack-free coating was achieved, demonstrating superior corrosion resistance. This was further corroborated by the resistance values of 23.891 Ω and 114.990 Ω for the acetone and methanol samples, respectively. Additionally, the corrosion rates of 0.075 (mmpy) and 0.0004 (mmpy) for the acetone and methanol samples further emphasized the superiority of methanol as a suspension medium. These findings unequivocally establish methanol as the optimal choice for achieving superior deposition quality and corrosion resistance in the context of the EPD method for stainless steel type 316L-based dental implants.