Wire Resistance Research Articles

Otpornost na koroziju ortodontske žice od legure nikl-titanijuma u veštačkoj pljuvački u prisustvu Kopiko bombona

Corrosion resistance of an orthodontic wire made of Ni-Ti alloy immersed in artificial saliva in the absence and presence of 500 ppm of Kopiko candy has been investigated by polarization study and AC impedance spectra. It is observed that corrosion resistance of Ni-Ti alloy immersed in artificial saliva in the presence of 500 ppm of Kopiko candy increases. Hence it is concluded that people clipped with orthodontic wire made of Ni-Ti alloy need not worry about taking Kopiko candy orally. When Ni-Ti alloy is immersed in artificial saliva in the presence of 500 ppm of Kopiko candy, Linear Polarization Resistance value increases from 347978 Ohmcm2 to 415003 Ohmcm2 ; corrosion current decreases from 1.346 x10-7A/cm2 to 1.105 x10-7A/cm2 ; charge transfer resistance value increases from 31945 Ohmcm2 to 44357 Ohmcm2 ; impedance value increases from 4.649to 4.819; double layer capacitance decreases from 1.596x10-10F/cm2 to 1.150 x10-10F/cm2 , and phase angle increases from 39.63° to 50°.

Effect of zirconium oxide nano-coating on frictional resistance of orthodontic wires.

Objectives:Minimizing the frictional force between orthodontic wire and brackets is imperative to safely obtain a more favorable result by applying lower loads. Several methods have been proposed for this purpose such as changing the wire shape/size, changing the bracket design, and coating wires with different materials. This study aimed to assess the effect of zirconium oxide (ZrO2) nano-coating on frictional resistance of three types of orthodontic wires.Materials and Methods:This in vitro, experimental study evaluated 42 pieces of nickel-titanium (NiTi), stainless steel (SS), and beta-titanium (TMA) orthodontic wires, and 42 maxillary canine brackets. The samples were divided into six groups with and without ZrO2 nano-coating. The nano-coating was applied on the wires using the sol-gel technique. The presence of ZrO2 nano-coating was evaluated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The surface roughness of the samples was evaluated using atomic force microscopy (AFM). The brackets and wire had a 5° angle relative to each other. The static and kinetic friction of the samples were evaluated in the presence of artificial saliva and occlusogingival movements in a universal testing machine. Data were analyzed by the Shapiro–Wilk's test, one-way ANOVA, Kruskal–Walli's test, Mann–Whitney U test, independent t-test, and Tukey's test.Results:ZrO2 nano-coating was only observed on TMA wires. The surface roughness of coated NiTi and SS wires had no significant difference from that of non-coated wires (P > 0.05). However, this difference was significant for TMA wires with and without the coating (P < 0.05). The static and kinetic friction were not significantly different between wires with and without coating (P > 0.05).Conclusions:ZrO2 nano-coating could only be applied on TMA wires, and had no significant efficacy for reduction of static or kinetic friction of TMA wires.

КОМПЕНСИРОВАНИЕ ПОТЕРЬ КОНТАКТНОЙ СЕТИ ЗА СЧЕТ ПРИМЕНЕНИЯ БОРТОВОГО НАКОПИТЕЛЯ ЭНЕРГИИ

The authors have analysed methods for energy loss reduction in catenary. Currently, there are at least two traditional methods: the first is aimed at decrease of distance between a power source and a consumer, the second - at reduction of resistance of a contact wire. The authors suggest a new method for compensation of catenary losses by installing on a board of electric motive power of an accumulating device that will compensate required power in case of energy shortage. The method allows reducing energy losses due to accumulated energy of the power source and, consequently, allows compensating it in the recuperation mode. As an accumulating device the authors have selected a Russian made supercondencer that can compensate more than a half of traction power system losses. It is equal to construction of an additional traction substation on a section with single-way feed. A simpler and a less expensive realization and high efficiency are the advantages of the proposed method.

Electrical conductivity of nanoring-based transparent conductive films: A mean-field approach

We have studied the electrical conductivity of nanoring-based, transparent conductive films, these being promising elements for flexible electronic devices. Both the wire resistance and the junction resistance were taken into account. We have calculated the dependency of the electrical conductivity on the number density of the rings. We have proposed a mean-field approach to estimate the dependency of the electrical conductivity on the main parameters. Comparison of direct computations of the electrical conductivity and the estimates provided by the mean-field approach evidenced the applicability of this approach for those cases where the wire resistance dominates over the junction resistance and where both resistances are of the same order. For these two cases, both the direct computations and the mean-field approach evidenced a linear dependence of the electrical conductivity of the films on the number density of the conductive rings. By contrast, the dependence of the electrical conductivity on the number density of the conductive rings is quadratic when the junction resistance dominates over the wire resistance. In this case, the mean-field approach significantly overestimates the electrical conductivity since the main assumptions underlying this approach are no longer fulfilled.

Salt Heat Treatment and Passivation to Improve the Corrosion Resistance of Nitinol (Ni-Ti)

Corrosion of nitinol (NiTi) is a major factor in the failure of implantable materials. Recently, as the importance of corrosion of metals has increased, testing according to international guidelines is essential. The purpose of this study was to evaluate the corrosion resistance of NiTi wire through heat treatment and passivation process. In this study, NiTi wire used two commercially available products and a self-manufactured stent. Experimental consideration was carried out according to ASTM standards. Heat treatment was carried out in an air or a salt furnace, and the corrosion was measured after additional process, such as passivation and scratch tests. As a result, the metal potential was rapidly decreased in the air furnace group. On the other hand, the potential of wires was dramatically increased in the salt furnace group compared to the air furnace group. The dislocation decreased below the acceptance criteria (>600 mV) within 60 s of heat treatment time in the air furnace. Moreover, the potential was dramatically improved, even after only 20 min of passivation treatment (1076 mV, 442% compared to the non-passivated group), and it continued to rise until 180 min. This phenomenon was similarly observed in the group of self-manufactured stents. The potential slightly decreased by the scratch process (93.1%) was significantly reduced by the air furnace process (315 mV, 24.4% of the nontreated group). In the passivated group of the air furnace sample with reduced potential, the potential was restored to the level before the air furnace (scratch stage) (1032 mV). In conclusion, the heat treatment is preferably carried out in a salt furnace rather than an air furnace, and the passivation process can be an advantageous tool to improve corrosion resistance by suppressing the oxidation process.

Use of superconducting liquid helium level sensor as a temperature sensor and its applications

A superconducting liquid helium level sensor has been used as a temperature sensor to monitor cooldown and warmup of the holding device. Temperature dependent resistance of NbTi wire is utilised for measuring surrounding gas space temperature (300 K-5 K) during the transition time. Theoretical calculation for the system revealed that during passage of current, temperature rise of the wire will be restricted to safe limits due to generation of high natural convection gas flow around the sensor, initiated by the its heating. Actionable decisions can be started based on this measurement for controlling cooldown and warm up process of the system. Depending on helium temperature, a dual use electronics meter has been proposed which can measure either gas temperature or liquid helium level using the same sensor. Utilising this principle any existing LHe level sensor can also be operated as a temperature sensor during thermal transition process.

In‐Depth Analysis of One Selector–One Resistor Crossbar Array for Its Writing and Reading Operations for Hardware Neural Network with Finite Wire Resistance

This work provides a comprehensive analytical analysis of one‐selector‐one‐resistor (1S1R) crossbar array (CBA) device for hardware neural network (HNN) applications. Simplified analytical device models are prepared from a particular 1S1R device to validate the analysis. The read margin (RM) analysis results show that the V/3 voltage scheme and reduced selector leakage are necessary to maximize the RM and maximum operable size N of the CBA, where N indicates the number of wires (word line or bit line). The write margin (WM) analysis results show that the unwanted switching of the unselected cell during the write operation is unlikely in the 1S1R CBA even with a large N value, despite a voltage drop along the interconnection wire. The analysis of simultaneous multiply‐and‐accumulate operations is conducted using the analytical method to examine the influence of voltage drop according to the wire and memory cells in HNN applications. Reducing the wire resistance and on‐state conductance increases the available N value when the selector operates near the threshold conditions. The proposed analytical model can estimate the maximum accuracy degradation of the HNN through the involvement of the unintentional voltage drop.

Robust and Reprocessable Artificial Muscles Based on Liquid Crystal Elastomers with Dynamic Thiourea Bonds

AbstractThis work reports a new class of liquid crystal elastomers (LCEs) cross‐linked with poly(ether‐thiourea) comprising a triethylene glycol spacer (LCE‐TUEG) wherein thiourea bonds impart a hydrogen bonding capability as well as permit dynamic covalent bond (DCB) exchange at elevated temperatures. While hydrogen bonding enhances the mechanical properties of LCE‐TUEG, the DCB allows the macromolecular network rearrangement of the LCEs, resulting in various useful properties that are not present in conventional LCEs, including the ability to undergo welding, melt and solution reprocessing, reprogrammable actuation, and self‐healing. By exploiting these dynamic features, electrically powered artificial muscles are fabricated that can be actuated by Joule heating using a resistive wire. In particular, an excellent specific work is demonstrated (≈65 J kg−1) for the artificial muscle, and full recyclability of both the LCE matrix and the metallic heating wire is achieved. Furthermore, a biomimetic artificial hand is created by welding and assembling multiple LCE‐TUEG films embedded with heating wires, followed by mechanical alignment. The integration of a microcontroller to the artificial hand enables the selective actuation of each finger, and various hand gestures are successfully demonstrated.

The Calculation Method of Ice Melting Schemes’ Relay Protection Settings and Clarification of the Ice Depositions Control Method on Steel Lightning Protection Wires

The method of current values calculation of overcurrent and undercurrent relay protections included in the complex of relay protection of ice melting schemes by alternating current on steel lightning protection wires of overhead transmission lines is analysed. A comparison with the generally accepted method, called the element-by-element method, is made. The element-by-element method is based on using the parameters of all the elements included in the ice melting scheme to calculate the maximum and minimum melting currents, from which the corresponding protections must be adjusted. These parameters have a significant variation, especially the active and internal reactive resistances of steel lightning protection wires at alternating current, what increases the calculation error. The proposed method, called the recalculation method, is based on the use of the trial melting mode parameters, carried out annually in the autumn season on lightning protection wires, with a duration up to 2 minutes. In difference to the usual practice, the trial melting has to be carried out 2 times with different currents. According to the parameters of the mode the settings of relay protection are recalculated using the given methods. The methodological and additional errors of the new method are estimated, that shows proposed method advantage. The parameters of the trial melting mode can be used to specify the methodology for remote control of ice formation (the length of the ice formation zone).

Measurement on the electrical conductivity of copper along the binodal curve in warm dense regime

This paper presents the electrical conductivity data of copper along the gas branch of the binodal curve in the warm dense matter (WDM) regime as a function of mass density and temperature. All data are obtained using the underwater wire explosion technique, in which vaporized copper cools along the gas branch of the binodal curve during the period of current dwell after the wire explodes. Mass density and temperature are measured by fast imaging and optical spectroscopy, respectively. Combining these data with electrical measurements of the wire resistance, we obtain the conductivities of copper along the binodal curve in the WDM regime. The electrical conductivity data measured here are expected to be helpful for developing a more accurate and reliable theory of transport properties in the WDM regime.

A Supply Chain Perspective on Beyond-Cu Replacement Metals for Nanoelectronic Interconnects

Due to significant resistivity scaling size effects in copper (Cu) and thickness scaling limitations for the associated high resistivity tantalum based Cu diffusion barriers, there has been significant interest in identifying alternative metallization schemes with lower overall effective resistivities. Using the combined semi-classical Fuchs-Sondheimer and Mayadas-Shatzkes equations for metal wire resistivity dimensional scaling, the product of electron mean free path (λ) and bulk metal resistivity (ρο) has been proposed as a potential figure of merit (FOM) for identifying metals with better resistivity scaling than Cu at nanometer dimensions. Using this FOM, over a dozen metals have been predicted so far with the potential to outperform Cu in future technologies. However, there have been relatively few experimental investigations for some of the most promising metals identified (i.e. Ir, Rh, and Os) due to their prohibitive expense.In this abstract, we seek to directly address the limited information on platinum group resistivity scaling as well as the costs impeding their investigation. For the former, we have performed a vast literature search of thin film resistivity for all the low λρο FOM (lower is better) candidate metals to robustly establish the resistivity scaling performance of rare platinum group metals (PGMs). For the latter, we have examined the supply chain for PGMs from earth to usable form in semiconductor manufacturing (i.e. sputter target, organometallic precursor, ...) to assess factors that influence pricing as well as search for opportunities to drive future cost reductions. Through the combined examination of a broader thin film resistivity data set and associated supply chain considerations, we identify and suggest additional metals that may merit greater consideration as potential Cu replacement metals.

A simulation model of a traction network taking into account the variable resistance of the contact line and a given power profile of the electric vehicle in MatLAB Simulink

The article describes an approach to the development of a simulation model of an electric transport traction network, taking into account the change in the resistance of the contact wire when the vehicle is moving. The advantage of the model is that it is executed using the building blocks of Simulink, visually reflects the topology of the traction network, and can be used for modeling both trolleybus and rail transport networks. As the initial data for the model, both standardized drive cycles and experimentally obtained modes of vehicle motion can be used.

Influence of ENO juice orally taken in on the corrosion resistance of orthodontic wire made of SS 18/8 in the presence of artificial saliva

Influence of ENO juice orally taken in on the corrosion resistance of orthodontic wire made of SS 18/8 in the presence of artificial saliva

Embedded Resistance Wire Technique for Epoxy Curing and Self-Healing of PET Thermoplastics

The aim of the present study is to apply an embedded resistance wire technique for curing of thermosetting resins as well as for the self-healing of thermoplastic polymers. The work consists of two parts. In the first part, Kanthal resistance wires embedded in a resin plate acted as heating elements when direct electrical current was flowing through them (Joule heating). During heating, the temperature was continuously monitored using a thermal camera, and accurate temperature times for fixed position diagrams as well as temperature positions for fixed time diagrams were calculated. The effects of curing with this method were evaluated by studying the three-point bending mechanical behavior of the cured resin, comparing it with the corresponding behavior of the same resin when cured using a conventional oven curing method at the same temperature. In the second part of the present work, the possibility of using the same technique for healing existing notches and flaws in a PET thermoplastic is explored. We examined whether providing energy through the resistance wires created the right amount of heat to heal the thermoplastic, or, more specifically, whether it closed the notches and eliminated the abrasions that were artificially created on the specimens. The technique using embedded resistance wires worked equally well, with interesting and promising preliminary results regarding the curing of thermoset resins and the healing of thermoplastics.

Disorder effects in topological insulator nanowires

Three-dimensional topological insulator (TI) nanowires with quantized surface subband spectra are studied as a main component of Majorana bound states (MBS) devices. However, such wires are known to have large concentration $N\ensuremath{\sim}{10}^{19}\phantom{\rule{4pt}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3}$ of Coulomb impurities. It is believed that a MBS device can function only if the amplitude of long-range fluctuations of the random Coulomb potential $\mathrm{\ensuremath{\Gamma}}$ is smaller than the subband gap $\mathrm{\ensuremath{\Delta}}$. Here we calculate $\mathrm{\ensuremath{\Gamma}}$ for recently experimentally studied large-dielectric-constant ${({\mathrm{Bi}}_{1\ensuremath{-}x}{\mathrm{Sb}}_{x})}_{2}{\mathrm{Te}}_{3}$ wires in a small-dielectric-constant environment (no superconductor). We show that provided by such a dielectric-constant contrast, the confinement of electric field of impurities within the wire allows more distant impurities to contribute into $\mathrm{\ensuremath{\Gamma}}$, leading to $\mathrm{\ensuremath{\Gamma}}\ensuremath{\sim}3\mathrm{\ensuremath{\Delta}}$. We also calculate a TI wire resistance as a function of the Fermi level and carrier concentration due to scattering on Coulomb and neutral impurities and do not find observable discrete subband-spectrum-related oscillations at $N\ensuremath{\gtrsim}{10}^{18}\phantom{\rule{4pt}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3}$.

10.3: A Fast Method for Equalizing Resistance in Touch Panel Design

In the field of special‐shaped panel design, TP (touch panel) design engineers need to manually complete the wiring routing work between the driven IC port and the TP pad port. Due to the routing channel is not regular, the equal line width method is usually adopted. Complete the routing in the channel in advance, and then adjust the routing line width to reduce the resistance discrepancy manually. As the resistance difference between the shortest and longest wire is relatively large, it is very extremely complicated for engineers to manually modify the line width to reach equal resistance for all the routing wires. At the same time, because the routing channel is often limited to a certain area, when adjusting one wire, the other wires will be affected. In order to achieve the purpose of automatic routing, we designed a routing method that distributes the line width in a limited area automatically, plus a method of superimposing serpentine wiring in the specified area to achieve the overall wiring resistance balance. In the paper, we referred to the idea of channel routing, first split the routing channel, and then routed in the split channel, and then connected the same net wiring in the channel, and adjusted the split channel according to the requirements of resistance. In the process of adjusting the resistance, the strategy of the simulated annealing algorithm is deployed to search the optimum routing result.

Contemporary State and Prospects of Female Protest Development: from Deprivation to Mobilization

Introduction. The article presents the analysis of the сontemporary state and prospects for the development of women’s protest in a global perspective. The research focuses on the study of the causes and nature of mass women’s protest in the context of the formation of a new system of relations between the authorities and society represented by certain social groups. The relevance of the problem is determined by the need for a political science analysis of modern practices, causes and forms of women’s protest, making a forecast of the prospects for the development of women’s social movements. Methods and methodology. The methodological basis of the research is the synthesis of the relative deprivation theory by T.R. Gurr and the resource mobilization theory by Ch. Tilly, which makes it possible to present women’s protest through the prism of both psychological (deprivation) and institutional determinants. The empirical basis of the work is the data (338 cases) of the quantitative study “The Women in Resistance (WiRe)”, that is available for secondary analysis in the Harvard Dataverse Repository. Analysis. Women’s protests represent an institutional and non-institutional form of changing the “political field”. A common peripheral role of women in the political space serves as a basis for the formation of a common identity among them. A high degree of consolidation, as well as an active role of women in protest, correlates with the success of collective action. Protests in which women play an active role are more peaceful in nature. This is due to the mediating role of women, which prevents the growth of tension in the conflict. Results. Based on the analysis of statistical information and case-study, it was revealed that the economic and legal structural similarity of states does not determine the nature of women’s protest participation in politics, which is more dependent on historical practices, previously achieved results of women’s protest, the presence of institutional structures that organize protests, as well as on the specific problems of women in the state. The prospects for the development of women’s protest and women’s social movements are determined by the level of success achieved. While in Western Europe and the USA, women’s social movements are fighting for the achievement of postmaterial values, due to the solution of the economic differentiation problems, in Latin America, women are fighting for their natural right to life and their own bodies. A vector of women’s protest is aimed at combating all types of discrimination, but the nature of specific problems is fundamentally different.

Design of Single Input Multiple Output Buck Converter with Light Load Efficiency

The major demand for portable electronics devices such as pagers, laptops, cellular phones etc. Single input multiple output (SIMO) converter will be proposed to give different supply voltages while keep up prolong battery life. A single-discharge (SDC) control scheme is introduce to simplify the Single inductor multiple output design, attain to low cross regulation, and to support board range of loads with decent efficiency of power. A Single discharge control single input multiple output buck converter with 4 outputs composed of comparators, phased-locked loop, finite state machine (FSM) controller, and an output stage. In addition to the basic switching functions, the FSM controller provides a state skipping feature to allow no-load regulation. Single input multiple output converter is available for less cost and used for maintaining long battery life and they are growing in vast range with rich feature portable electronic device. The design of converter is designed for limited range for prolonged battery life. The SIMO converters are used for the reduction of cost and switching losses, hence improve system efficiency. In our study, we proposed buck converter topology with single input of 24v and multiple output of 12v and 5v. The 12v voltage is used for electric vehicles. In electric vehicles it is used in horns and headlights. 5v voltage is used for small signal and stability analysis. The simulated conversion efficiency for peak power is 86% the power ranging for output is 50 to 300mW. The ICs exhibit has a low measured peak efficiency of 73% and cross regulation of 0.24 mV/mA because of parasitic bond wire resistance. The proposed system is simulated in MATLAB/Simulink software.

Application of On-Line Sorbentless Cryogenic Needle Trap Extraction Coupled with GC-FID for Analysis of Some Organic Volatile Impurities in Solid Pharmaceuticals.

An automated sorbentless cryogenic needle trap device (ASCNTD) was developed for the extraction of organic volatile impurities (OVIs) from solid pharmaceuticals prior to their determination by gas chromatography (GC). In this method, a new set up was designed and used to extraction of several OVIs from ceftazidime, ceftriaxone sodium and amoxicillin. For this purpose, a proper amount of the sample was transferred into the extraction vessel. The sample headspace components were started to circulate through a needle with a flow rate of 20mLmin-1. The OVIs were trapped on the inner surface of a needle placed on top of the sample by flowing liquid nitrogen. After a predetermined time, the coiled nichrome resistance wire placed into the hollow ceramic rod was heated and the trapped analytes were desorbed and swept into the GC capillary column using the carrier gas. The effective parameters such as volume of the sample vial, headspace flow rate, extraction temperature and time, and desorption conditions have been investigated. Qualification studies reveal that pyridine (as a degradation product of ceftazidime), methylene chloride, diethylamine, triethylamine, isopropyl alcohol and n-butyl acetate are the main impurities in the studied pharmaceuticals. Detected OVIs were quantitated using external standard method. The obtained relative standard deviation values were <8%, and the limits of detection (LOD) for the detected OVIs were in the range of 1-34ngg-1.

A multi-motion bionic soft hexapod robot driven by self-sensing controlled twisted artificial muscles

Artificial muscles have unique advantages for driving bionic robots because their driving mode is similar to biological muscles. However, there is still a big gap between the existing artificial muscle and biological muscle in performance. The twisted artificial muscles (TAMs) from nylon 6,6 provides a low-cost, high integration, low hysteresis driving method. But as a soft actuator, the control of the TAM is so complex that the advantage of excellent embeddedness has not been brought into play. This work presents a self-sensing control method for the TAM by monitoring the real-time resistance of the heating wire which realizes the accurate controlling of the TAM temperature. The simultaneous control of 18 TAMs is realized by using the self-sensing control method. By using a new step walking method based on the principle of insect bionics, a bionic soft hexapod robot with both multi-motion and load capacity is realized. Besides, due to the excellent environmental adaptability of the TAM, the bionic robot can realize amphibious motion both on land and underwater conditions, and the corresponding maximum load capacities are 300 g and 1 kg, respectively. This work not only provides a reliable self-sensing control method of the TAMs but also promotes the development of bionic soft robots.