Resistance Values Research Articles

Shilajit Mitigates Diabetes‐Induced Testicular Dysfunction in Mice: A Modulation in Insulin Sensitivity, Germ Cell‐Junctional Dynamics, and Oxido‐Apoptotic Status

Diabetes is a chronic metabolic condition that causes testicular damage by high oxidative stress, rendering 35% of afflicted people infertile. Shilajit is a traditional Indian medicine known for its antioxidant, antidiabetic, and aphrodisiac properties. However, its effectiveness on diabetes‐induced testicular dysfunction remains unclear. Therefore, the current investigation aimed to determine whether Shilajit could restore testicular functions in diabetic mice. Two days postpartum male Parkes mice received a single intraperitoneal injection of streptozotocin (STZ) (90 mg/kg BW) to induce diabetes. Three months postinjection, the effects of daily Shilajit (100 and 200 mg/kg BW) treatment were evaluated for one spermatogenic cycle in adult diabetic mice, using Empagliflozin (10 mg/kg BW) as a positive control. In STZ‐induced diabetic mice, testicular functions were compromised due to disruptions in testosterone biosynthesis, changes in germ‐cell ratios, and increased oxidative stress and apoptosis. Shilajit restored glycemic status in diabetic mice by significantly decreasing serum glucose, insulin level, and homeostasis model assessment of insulin resistance (HOMA‐IR) value while increasing insulin sensitivity. These effects were comparable to those observed with conventional antidiabetic medication Empagliflozin. Further, Shilajit stimulates steroidogenesis and germ cell dynamics of diabetic mice by increasing the activity of StAR, 3β‐HSD, and 17β‐HSD enzymes and 1C:2C, 4C:S‐Ph, and 1C:4C germ cell ratios, respectively. Shilajit also improves blood–testis barrier (BTB) functioning by increasing expression of ZO‐1, Connexin‐43, N‐Cadherin, and β‐catenin as well as oxidative status and apoptosis by modulating NF‐E2–related factor 2 (Nrf‐2)/heme oxygenase 1 (HO‐1) signaling and Bax/Bcl‐2 ratio. Subsequently, Shilajit improved the histoarchitecture of testis and epididymis in diabetic mice and recovered both qualitative and quantitative sperm parameters, as seen by higher percentages of sperm motility, viability, and normal sperm morphology as well as increased sperm numbers in cauda epididymis. In summary, Shilajit restores glycemic status, increases insulin sensitivity, stimulates steroidogenesis, and improves testicular functions through Sertoli cell and Nrf‐2/HO‐1 signaling in STZ‐induced diabetic mice.

Comparative biology of chlorantraniliprole selected and unselected Chrysoperla carnea (Stephens) populations: Stability of resistance, inheritance mode, and realized heritability.

Insecticide resistance in natural enemies can be used as a positive trait in integrated pest management programs by increasing the compatibility of two important tools; biological and chemical control. In this experiment, a field population of Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae) was selected with chlorantraniliprole for 35 generations (Chlor-Sel) developed a 100.32-fold resistance level compared to an unselected population (Unsel). The dominance values of resistance for reciprocal crosses confirmed incomplete dominance inheritance of chlorantraniliprole resistance. The results on projected rate of chlorantraniliprole resistance showed that at 10% to 90% survival in each selection and a realized heritability value of 0.19, the Chlor-Sel will require only 3 to 26 generations (Slope=1.15) to increase a 10-fold level of resistance. The results of the age-stage life table experiment showed that fecundity, oviposition days, male and female longevity, net reproductive rate (Ro), and gross reproductive rate (GRR) of both crosses were significantly increased compared to their parents. The fecundity of reproductive females, male and female longevity, Ro, generation time (T), and GRR of Chlor-Sel were not significantly different than that of the Unsel strain of C. carnea. In conclusion, chlorantraniliprole resistance in C. carnea has an autosomal, polygenic, and incompletely dominant inheritance mode and C. carnea has potential to develop resistance that leads to fitness benefits. This information will help in management of insect pests by deploying resistant strains with selected insecticides and conservation of these natural enemies in fields with sustaining resistance genes.

ELECTROCHEMICAL CORROSION EVALUATION OF SnSb ELECTRODEPOSITED COATINGS

SnxSb(1−x) coatings were electrodeposited from 1ChCl:2EG on copper. The corrosion resistance of the electrodeposits was evaluated in 0.1 mol dm-3 of NaCl. The characterization was performed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). Voltammetric profiles showed that the electrodeposition potential shifted towards less positive values with increasing Sb3+ concentration. SEM images revealed that the coatings exhibited grains and clusters. EDS analyses showed that the Sb content increased with the Sb3+ concentration. XRD results indicated the formation of the SbSn phases such as Cu2Sb, Cu6Sn5, and Cu6(Sn,Sb)5. The potentiodynamic polarization (PP) curves showed that Sn and Sn77Sb23 presented a passive potential region, while Sn37Sb63 had an active dissolution in the electrolyte. Immersion tests were performed for 24 h and XRD results revealed Cu, Sn, SnO, SbSn and Sb2O4 phases. Considering 48 h, Cu, CuSn, SnO2 and SnSb phases were identified. The polarization resistance values of 4.60, 14.69 and 1.81 kΩ cm2 were achieved for Sn, Sn77Sb23, and Sn37Sb63, respectively. The EIS results suggested that adding Sb3+ improves corrosion resistance for SnSb samples with higher Sn content. For Sn77Sb23, the charge transfer resistance was 10.5 kΩ cm2, for Sn and Sn37Sb63 1.15 and 1.46 kΩ cm2, respectively.

Assessment of UV-Aging of Crosslinked Polyethylene Cable Insulation by Electrical Measurements, FTIR and DSC Analyses

Abstract In this study, the effect of UV-radiation on the structural properties of crosslinked polyethylene (XLPE) power cable insulating material was investigated as a function of aging time. XLPE specimens were exposed to UV-radiation for 200 hours using low-pressure vapor fluorescent lamps. Electrical resistivity values, influence and leakage currents, and charging and discharging currents of specimens were measured and quantified. In addition, structural changes in polyethylene chains were also evaluated with Fourier transform infrared (FTIR) analyses and high-temperature oxidation stability was correlated with the level of structural deterioration as a result of UV-aging through determination of oxidation induction time and oxidation onset temperature in differential scanning calorimetry (DSC). Experimental results showed that the electrical properties of XLPE materials were significantly affected by UV radiation and resulting structural changes can be successfully assessed with electrical measurements as a rapid, easy, and reliable tool. It was also confirmed that FTIR and DSC analyses can be used to evaluate oxidative aging level of XLPE and olefinic polymers such as polyethylene and polypropylene, polyolefin-based elastomers. This study also suggests an analytical methodology to constitute the relationship between the thermal and physical properties of polyolefins and their service life.

Fracture Resistance of Chairside CAD/CAM Lithium Disilicate Partial and Full Coverage Crowns and Veneers for Maxillary Canines.

This study aimed to assess the fracture resistance of chairside computer assisted design and computer assisted manufacturing (CAD-CAM) lithium disilicate partial and full-coverage crowns and veneers for maxillary canines. Forty-eight restorations for maxillary right canines (12 per group) were designed as follows: (1) partial crown with finish line in the upper middle third; (2) partial crown with finish line in the lower middle third; (3) traditional labial veneer; and (4) traditional full-coverage crown. Restorations were fabricated out of lithium disilicate (Amber Mill, Hassbio) using a chairside CAD-CAM system (Cerec Dentsply Sirona). Partial and full crowns and veneers were treated with a primer system (Monobond Plus, Ivoclar Vivadent) and cemented using dual-cure resin cement (Variolink Esthetic, Ivoclar Vivadent) and cemented to printed resin dies. Subsequently, the restorations were subjected to 10,000 thermocycles between 5°C and 55°C with a dwell time of 30 seconds. The restorations were then loaded axially on the incisal edge in compression to fracture with a flat indenter. Full-coverage crowns displayed the highest fracture resistance (809±28.57 N) followed by partial crowns with finish line in lower third (649±21.74 N) and crowns with finish line in upper third (421±17.46 N). Veneers displayed the lowest fracture resistance values (259±15.69 N). The fracture resistance of partial and full-coverage crowns and veneers was significantly influenced by the design. Full coverage crowns displayed the highest fracture resistance and partial crowns showed higher fracture resistance than traditional veneers.

Texture and skid resistance of asphalt mixtures with crumb rubber: laboratory assessment

ABSTRACT The skid resistance of asphalt pavements is related to pavement texture. Also, the addition of crumb rubber (CR) from end-of-life tires could improve friction, although this aspect of CR pavements has not been sufficiently studied. In this study, three types of mixtures were produced, a semi-dense mixture AC, a stone matrix asphalt SMA mixture, and an open-graded mixture BBTM. Each one was tested with three percentages of CR: 0.0, 0.75, and 1.50%. The surface of these mixtures was worn and polished in successive stages. At each stage, the macrotexture and microtexture data were obtained using a laser texturometer, and the skid resistance was measured using the British Pendulum Test (BPT). From these data, prediction models for the British Pendulum Number (BPN) value were adjusted based on macrotexture, microtexture, and CR content. According to these models, the microtexture of the pavement influences the BPN value more than the macrotexture for all types of mixtures studied. In addition, CR explains part of the BPN value of skid resistance in the SMA mixture and in the open-graded BBTM mixture. As for the semi-dense mixture, the presence of CR does not seem to significantly influence the skid resistance.

Characterization of passive layer formation kinetics of Zn5Al hot-dip galvanized coatings using gel electrolytes

Purpose The formation of a natural passive layer on hot-dip galvanized coatings increases their corrosion resistance. Although the basic mechanisms of passive layer formation are known, the quantitative determination of the evolution of its passive character, in particular its surface resistivity, and its development under atmospheric weathering remains largely unexplored for zinc-5% aluminum (Zn5Al) coatings. Design/methodology/approach Zn5Al-galvanized test sheets were exposed to atmospheric weathering for four weeks during summer and winter, and the development of polarization resistance measured using a gel-type electrolyte over these periods. Further investigation included stripping away the formed passive layer midway through the exposure period and electrochemical characterization of the passive layer that re-formed after under continue weathering. Findings The results showed a steadily increasing resistivity of the corrosion product (passive) layer over the course of the weathering period; this was confirmed by supplementary macroscopic and microscopic analyses. Exposure conditions affected the speed of development. Polarization resistance values were higher by approximately 50 kΩcm2 during the winter compared to summer. Upon interruption of exposure and removal of the passive layer, it rebuilt up much more rapidly after exposure resumed in comparison with the initial layer. Originality/value The use of gel electrolyte for determining the polarization resistance of a metal surface is a novel and useful method. To the best of the authors’ knowledge, this study has, for the first time, established the suitability of this electrochemical test method for quantifying the coating resistance of Zn5Al galvanized steel after calibrating the measurement parameters.

LITHOLOGICAL DEDUCTIONS AND THE EVALUATION OF GROUNDWATER POTENTIALS FROM GEO-ELECTRICAL SOUNDINGS IN THE BENDE-AMEKI FORMATION OF EHIME-MBANO AREA, SOUTHERN NIGERIA

Lithological deductions and evaluation of groundwater potentials from Geo-electrical soundings in the Bende-Ameki Formation of Ehime-Mbano Area, Southern Nigeria, was carried out by imploring the vertical electrical sounding (VES) technique. A total of nine VES points were obtained using the ABEM SAS 1000 Terrameter. The study reveals that the depth of the shallow wells in the area (upper aquifer) ranges from 12-22m and falls within the 3rd and 4th geo-electric layers with resistivity values ranging from 240m - 2500m; while the 2nd aquifer ranges from 34-45m and with range of resistivity values of 190m - 300m. The depth to the 3rd aquifer ranges from 70 120m, while that of the 4th aquifer is 130-300m. The data obtained after partial curve matching and computer iteration indicates a total of 8 - 10 geoelectric layers with inferred lithologies namely: silt, clay, fine-grained sand, medium-grained sand, coarse-grained sand and sandstone. Results show that most of the aquifers are hosted within the silts and fine-grained sands with the exception of a few locations with medium-grained and coarse-grained sands. By using the Dar-Zarrouk parameters, the overburden protective capacities of the aquifers in the study area were evaluated as poor, weak and moderate in some locations. It was concluded that in the area, sand mining (excavation) is a potential economic source except in the vicinity of VES 9.

Pressure Drop Analysis of Turbine Housing Model with Circular Sliced Pipe for Micro Hydropower Generation

Energy independence is a government program aiming to meet society's energy needs evenly. Steps to increase energy independence in the new and renewable energy sector include hydro-energy generation. One of the important components of a hydro generator is the penstock pipe and turbine housing, which channels water and then pushes and drives (spins) the turbine with the flow of water to produce electrical energy. The turbine housing flow design innovation must provide a function as an optimal fluid conductor by minimizing the resistance that occurs when fluid flows towards the turbine housing and rotates the turbine optimally. The scope of this research includes analysis of the phenomenon of energy loss flowing in circular pipe slices in hydroelectric power plant turbine housings with influencing factors such as friction, turbulence, and flow resistance, as well as measuring the pressure drop in circular pipe slices. The model developed is a circular slice bend with angles of 180 degrees, 270 degrees, 360 degrees, and 450 degrees, taking into account the optimal curvature ratio (R/D) of 3.5. Based on previous research, 90-degree wedge bends with many slices (n_(90-degree)) 4 to 6 or  4 and pressure drop coefficient (C_(pd-th)) obtained 180-degree (0.333 – 0.200), 270-degree (0.445 – 0.277), 360-degree (0.527¬ – 0.339), 450-degree (0.587 – 0.390) with a bend length L, an elevation reduction angle  and a 1.5D upstream-downstream elevation difference to avoid contact between the upstream and downstream bends. The results obtained from this research are the slice modules that can be used and the resistance coefficient values that arise from the slice modules. The more slices selected according to the angle of inclination chosen, the smoother the resulting circular bend shape and the lower the resistance value, but the work will be more difficult. The most optimal slice module is the number of slices that allow its implementation, and the resistance coefficient is small. By knowing the optimal resistance coefficient value, the resulting pressure drop can be predicted to maximize the thrust to rotate the turbine.

Miniaturization Potential of Additive-Manufactured 3D Mechatronic Integrated Device Components Produced by Stereolithography.

Three-dimensional Mechatronic Integrated Devices (3D-MIDs) combine mechanical and electrical functions, enabling significant component miniaturization and enhanced functionality. However, their application in high-temperature environments remains limited due to material challenges. Existing research highlights the thermal stability of ceramic substrates; yet, their reliability under high-stress and complex mechanical loading conditions remains a challenge. In this study, 3D-MID components were fabricated using stereolithography (SLA) 3D-printing technology, and the feasibility of circuit miniaturization on high-temperature-resistant resin substrates was explored. Additionally, the influence of laser parameters on resistance values was analyzed using the Response Surface Methodology (RSM). The results demonstrate that SLA 3D-printing achieves substrates with low surface roughness, enabling the precise formation of fine features. Electric circuits are successfully formed on substrates printed with resin mixed with Laser Direct Structuring (LDS) additives, following laser structuring and metallization processes, with a minimum conductor spacing of 150 µm. Furthermore, through the integration of through-holes (vias) and the use of smaller package chips, such as Ball Grid Array (BGA) and Quad Flat No-lead (QFN), the circuits achieve further miniaturization and establish reliable electrical connections via soldering. Taken together, our results demonstrate that thermoset plastics serve as substrates for 3D-MID components, broadening the application scope of 3D-MID technology and providing a framework for circuit miniaturization on SLA-printed substrates.

Courage and Charm: Annedore Leber, German Resistance, and Memory Activism, 1946–9

Interest in memory activism is the methodological starting point for this account of Annedore Leber, Social Democratic politician in post-1945 Berlin and surviving member of the resistance group that plotted the assassination attempt of 20 July 1944 on Adolf Hitler. Beginning in 1946, her memory work entailed a narrative to influence Germans, prone to view that plot as treasonous, to reconsider the resistance. Initially, her often-articulated contempt for the nation that had backed Hitler made this effort problematic: which Germans comprised her intended audience? The Cold War gave her an opening. She compared Nazi Germany to the Soviet Union. She called on Germans who opposed communism to appreciate the courage and love of freedom that informed anti-Nazi resistance. She re-enacted those resistance values by confronting the communists publicly. The other methodological angle regarding this research comes from awareness that the German patriarchy, despite defeat, was largely intact. Comments on Annedore Leber as a woman appeared in press coverage of her confrontation of communist leaders; men challenged her version of the resistance. How she met those challenges, assumed her stance as a politically active woman and expressed the necessity for women to engage in politics are key to understanding her activism.

EXPERIMENTAL STUDY OF OPTIMAL POWER CONSUMPTION CONTROL DEVICE FOR THE ELECTROMAGNETIC DRIVE OF A CONTACTOR

One of the priority scientific and technological directions of development of the Russian Federation in the field of energy, is energy and resource saving. In this regard, to ensure the competitiveness of the electrical products market, the issue of research and development of low-voltage electromagnetic switching equipment with low values ​​of power consumption and weight and size indicators is relevant. The purpose of the study is to reduce the power consumption of the electromagnetic drive of the contactor in the holding mode and to increase the electrical wear resistance of the main contacts of the contactor. Materials and methods. The basis of the study was the analyzed existing solutions for the schemes and algorithms for controlling the electromagnetic drive in various sources of information. The electromagnetic drive of the vacuum contactor of the КВ1-160 series was adopted as the initial object of the study. Main parameters of the electromagnetic drive of the contactor КВ1-160: nominal control voltage of 220 V DC, winding resistance values ​​preliminarily measured by the universal voltmeter АВМ-4306 and the testing device РЕТОМ-21 are 62 Ohm, the power consumption of the contactor electromagnet with a standard unit in the holding mode is 15.2 W. The research used the methods of analysis and synthesis, measurement, planning and conducting an experiment. Research results. The paper presents the results of the development and study of a control device for electromagnetic drives, which ensures a decrease in the power consumption of the electromagnetic drive in the holding mode, as well as an increase in their electrical wear resistance. A control circuit for a single-winding electromagnetic drive is proposed. A brief description of the operation of the control device prototype based on a microcontroller is given. Experimental studies of the control device prototype are carried out using a three-stage electromagnetic drive control algorithm. Conclusions. The results of the experimental studies showed the operability of the prototype sample of the contactor electromagnetic drive control device according to the proposed circuit. A reduction in the power consumption of the EMF in the holding mode was achieved, which amounted to 25 W. A slight (approximately 10%) reduction in the vibration time of the main contacts was ensured, which will lead to an increase in their electrical wear resistance.

Development of a mathematical model of dependence of specific volumetric electrical resistance of SIW-4 insulation on factors affecting its reliability

Insulation of self-supporting insulated wire (SIW-4) is the object of the study, and the subject of the study is a mathematical model of the dependence of the specific volume electrical resistance of the SIW-4 insulation on the factors affecting its reliability. The resulting mathematical model will allow us to proceed to the development of a method for predictive assessment of the residual life of the insulation material of the conductor under study. At the first stage of the work, the influence of external factors on the electrical parameters of the SIW-4 insulation material has been studied. When forming the goal of the study, namely, obtaining a mathematical model of the dependence of the specific volume resistance of the wire insulation on the influence of external factors, difficult operating conditions have been taken into account. SIW-4 is intended for use outside buildings, i. e. it is exposed to solar radiation, wind load, precipitation, temperature changes, etc. Within the framework of this study, the following most significant factors have been considered: alternating electric current, ambient temperature and period of operation. These factors have been selected taking into account the possibility of conducting a multifactorial experiment and fully characterize such properties of product reliability as durability and failure-free operation. During the multifactorial analysis, the task was to select the minimum and maximum values of each factor under study, followed by the compilation of a planning matrix for a full factorial experiment. The resulting mathematical model allows us to determine the effective value of the specific volume electrical resistance of the SIW-4 insulation material depending on its operation under the given specific conditions. It also opens up the possibility of developing the second stage of the study, associated with the construction of an algorithm for the method of predictive assessment of the residual life of the insulation material of the conductor under study.

Joint interpretation of magnetic, transient electromagnetic, and electric resistivity tomography data for landfill characterization and contamination detection

AbstractGeophysical techniques have become increasingly crucial for characterizing landfills, offering noninvasive methods for subsurface exploration and contamination assessment. In this study, an integrated geophysical approach—utilizing magnetic, electrical resistivity tomography (ERT), and transient electromagnetic (TEM) surveys—was employed to characterize the Weidenpesch landfill in Cologne, Germany and assess potential groundwater contamination. The results from these methods were consistent, effectively delineating the landfill boundaries and identifying possible contamination. The waste body was distinguished by its relatively low resistivity values with an average value of 1–10 Ω·m in the western and central parts of the landfill and 20–50 Ω·m at its eastern part in contrast with the surrounding high-resistivity gravelly sand layer (several hundreds of Ω·m), and a depth of up to 15 m. The variability in conductivity and magnetic susceptibility across different landfill sections indicated the heterogeneity of buried materials. Additionally, the ERT and TEM data indicate low resistivity values (below 5 Ω·m) at depths of 20–25 m. A correlation with the borehole data suggests that this may represent a contaminated coal/clay layer. Furthermore, repeated TEM measurements revealed significant variation in subsurface conductivity over time, highlighting the need for continuous monitoring. This study demonstrates the effectiveness of an integrated geophysical approach for providing a comprehensive understanding of subsurface landfill conditions, which is essential for informed environmental management and remediation.

STUDI NILAI RESITENSI ELEKTRODA PENTANAHAN MENGGUNAKAN METODE TIGA KUTUB PADA KONDISI TANAH BERBEDA

The grounding system serves as a safe path for electrical current to flow to the ground, which is important in preventing the risk of equipment damage and safety hazards. One of the critical parameters in this system is the resistance of the ground electrode, which can be measured using the three-point method. Based on PUIL 2000, the recommended grounding resistance value for electrical installations must be less than 5 ohms so that the system can work optimally and safely. The three-pole method is known to be accurate because it minimizes the influence of the environment around the electrode. However, factors such as soil type, humidity, and mineral content greatly influence the resistance of the ground electrode. Therefore, this study aims to evaluate the resistance of grounding electrodes in various types of soil, such as clay, swamp soil, damp sandy soil, dry soil, and rocky soil. Research results: The best grounding electrode resistance values ​​were obtained in clay and moist sandy soil (coastal). Meanwhile, the resistance value of the ground electrode for dry soil, rocky soil, and swamp soil does not meet the standard of ≤ 5 ohms. The factors that cause the resistance value of the ground electrode not to meet the standard are because in swampy soil the soil is dominated by insulating organic material and low content of conductive minerals. Also, moisture imbalance, electrode corrosion, and less-than-optimal electrode installation contribute. At the same time, dry soil and rocky soil are characterized by having a high level of resistivity due to low water and mineral content and a texture that does not support optimal electrical conductivity where field measurement results are not yet available. Meets the standard ≤ 5 Ω

Vascular hemodynamic effects of penile revascularization surgery and the role of resistive index in follow-up

BackgroundTo evaluate the effects of penile revascularization surgery on penile vascular hemodynamics and to assess the utility of the resistive index (RI) as an objective parameter for postoperative patient follow-up.MethodsThis study included a total of 35 patients who underwent penile revascularization. Penile color Doppler ultrasonography was performed preoperatively and at the third postoperative month to evaluate cavernosal arteries, dorsal arteries, deep dorsal vein, and inferior epigastric artery. During these evaluations, peak systolic velocity, end diastolic velocity, and resistive index were measured. The International Index of Erectile Function questionnaire was administered before surgery and at the third postoperative month. In addition, corpus cavernosum electromyography and cavernosometry tests were performed in all cases preoperatively. Anastomotic patency was assessed using computed tomography angiography at the end of the follow-up period.ResultsThe mean preoperative resistive index values were determined to be 0.74 ± 0.07 and 0.73 ± 0.09 cm/s for the right and left cavernosal arteries, respectively, and these values increased to 0.95 ± 0.09 and 0.96 ± 0.06 cm/s, respectively, at the last postoperative control. The mean International Index of Erectile Function-5, 15 scores for the right and left cavernosal arteries were 8.52 ± 4.83 and 19.4 ± 8.54, respectively, preoperatively, and these scores improved to 15.26 ± 4.50 and 35.76 ± 13.65, respectively, at the last postoperative follow-up.ConclusionThe results of this study suggest that the resistive index can be used as an objective parameter in the diagnosis of erectile dysfunction of vascular origin and in the follow-up and management of the disease following penile revascularization.Trial registrationNCT06350019/04/03/2024 (retrospectively registered).

Development of Single-Walled Carbon Nanotube-Based Electrodes with Enhanced Dispersion and Electrochemical Properties for Blood Glucose Monitoring.

The evolution of high-performance electrode materials has significantly impacted the development of real-time monitoring biosensors, emphasizing the need for compatibility with biomaterials and robust electrochemical properties. This work focuses on creating electrode materials utilizing single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs), specifically examining their dispersion behavior and electrochemical characteristics. By using ultrasonic waves, we analyzed the dispersion of CNTs in various solvents, including N, N-dimethylformamide (DMF), deionized water (DW), ethanol, and acetone. The findings revealed that SWCNTs achieved optimal dispersion without precipitation in DMF. Additionally, we observed that the electrical resistance decreased as the concentration of SWCNTs increased from 0.025 to 0.4 g/L, with significant conductivity enhancements noted between 0.2 g/L and 0.4 g/L in DMF. In constructing the biosensor platform, we employed 1-pyrenebutanoic acid succinimidyl ester (PBSE) as a linker molecule, while glucose oxidase (Gox) served as the binding substrate. The interaction between Gox and glucose led to a notable decrease in the biosensor's resistance values as glucose concentrations ranged from 0.001 to 0.1 M. These results provide foundational insights into the development of SWCNT-based electrode materials and suggest a promising pathway toward the next generation of efficient and reliable biosensors.

DLTS characterisation of 107 MeV krypton ion-irradiated nitrogen-doped 4H-silicon carbide

Swift heavy ions, such as krypton ions, play a significant role in developing and enhancing the performance of various devices. In this study, the influence of Kr2+ on nitrogen-doped 4H-silicon carbide has been investigated using deep level transient spectroscopy (DLTS). Krypton ions, with an energy of 107 MeV, were used to irradiate the Au/Ni/4H-SiC Schottky barrier diodes (SBDs) at a fluence of 1 × 1010 cm–2 at room temperature (300 K). Before the irradiation of the samples, the electrical measurements revealed good rectifying behaviour. However, rectification properties of the Au/Ni/4H-SiC SBDs were completely lost after irradiation at a fluence of 1 × 1010 cm–2. Annealing was performed at 300 °C in flowing argon, and the current–voltage (I–V) and capacitance–voltage (C–V) revealed partial rectification. DLTS of the as-grown devices analyses revealed the presence of four deep level defects. After annealing the irradiated device, the DLTS spectra showed a reduction in the intensity of the E0.10 and the disappearance of the E0.12 as well as the E0.16 defects compared to that as-grown. Two defects with energies of 280 and 410 meV showed inverted peaks, as would have been expected from minority carriers trap instead of majority carriers, which led to confusion as the peaks were inverted. It was concluded that the peculiar characteristics of DLTS measurements on SBDs may be due to the extremely high value of the series resistance as well as the low capacitance. The results of this study provide insight into the behaviour of SBDs under extreme irradiation and can be used to improve the radiation tolerance of electronic devices made from SiC.

马铃薯挖掘机仿真与试验

In this study, the potato excavator with loosening shovel was designed in order to solve the problems of serious soil obstruction and high excavation resistance during the potato harvest. Using EDEM discrete element simulation software, potato excavation simulation experiments were carried out on soil broken effects and excavation resistance. Through the comparative analysis with loosening shovel and without, the results showed that the increase of soil broken effects was close to 52%, and the excavation resistance decreased by 16.57%. Through the two-factor and three-level field orthogonal experiment with excavation depth and loosening depth as influencing factors, the optimal operating parameters was determined for potato excavators: the excavation depth was 23 cm and the loosening depth was 20 cm. At this time, the excavation potato rate was 98.21%, and the rate of damaged potato was 1.31%. The traction resistance was 1826 N, which met the requirements of relevant industry standards. Through comparative analysis of simulation experiments and field experiment, it was found that when the excavation depth was 23 cm and the loosening depth was 20 cm, the error value of traction resistance was 11.3% between simulation experiments and field experiments. The discrete element simulation analysis can provide a preliminary reference for potato excavation design.

Performance and durability of additively and subtractively manufactured resin-based onlay restorations after thermomechanical aging.

To evaluate the effect of material type on dimensional stability, occlusal surface wear, fracture resistance, and failure behavior of resin-based onlay restorations. A mandibular right first molar typodont was prepared and digitized using an intraoral scanner to virtually design an onlay restoration with the minimum occlusal thickness of 1.5mm. Resin-based onlay restorations (n = 15 per group) were fabricated either additively from 2 different resins indicated either for definitive or interim use or subtractively with a composite resin. After cementing onlays to corresponding dies, each of them was digitized before and after thermomechanical aging (B-STL and A-STL), and then subjected to load-to-failure test to evaluate fracture resistance. The B-STL and A-STL of each onlay were also compared to assess the dimensional stability and occlusal surface wear. One-way analysis of variance and Tukey honestly significant difference tests were used to evaluate dimensional stability, occlusal surface wear, and fracture resistance. The chi-square test was used to evaluate the Weibull modulus and characteristic strength among the groups (α = 0.05). Material type affected investigated outcomes (p<0.001). The additively manufactured resin indicated for definitive use led to the highest external surface deviations and the additively manufactured resin indicated for interim use led to the highest mesiodistal width deviations (p≤0.033). The onlays fabricated from the additively manufactured resin indicated for definitive use had the highest occlusal surface wear, while those in composite resin had the lowest (p≤0.006). The composite resin onlays had the highest fracture resistance values and reliability (p≤0.035). Tested subtractively manufactured composite resin had the lowest occlusal surface wear with the highest fracture resistance and reliability. Additively manufactured resins had lower dimensional stability, while tested resin for additively manufactured definitive restorations had the highest occlusal surface wear.