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In the present paper, the possibility of magnetization of HTSC tape by means of pumping by a local magnetic field is considered. Within the framework of the critical state model, the calculation of the density of the induced currents and the magnetization of a square (12 × 12 mm) fragment of a second-generation HTS tape (YBCO) was made. The model considers real dependence of the critical current density on the magnetic field and has been successfully tested previously. In the sample, the currents were induced by the impact of a local magnetic field. The size of the localized area of the external magnetic field to be considered was much smaller than the size of the HTS sample. It is showed that the repeated cyclical impact of the local outer field leads to the accumulation of the total magnetic moment in the sample up to a magnitude of 94% of the theoretical magnetization limit for this sample. The results obtained make it possible to optimize the mode of magnetization of a square fragment of a tape (or a stack of tapes) when implementing a magnetic flux pump. The experimental studies showed results comprisable well with theoretical ones. [ABSTRACT FROM AUTHOR]

This paper studies the influence of the thermal disturbance process on the electro-thermo-mechanical properties of quasi-isotropic strand (Q-IS) in self-field. We first measured the heat transfer time as well as the longitudinal temperature distribution through experiments and compared them with simulated results. Subsequently, through the finite element analysis, the transversal distribution of the temperature in the center of the strand and the attenuation of the critical current during the thermal disturbance are obtained. Finally, with considering the uniformity of the temperature distribution, the internal stress of the strand under different operating currents was studied. The results show that compared to the strand formed by directly stacked tapes, the Q-IS has advantages of uniform temperature distribution, less attenuation of critical current, and lower amplitude of internal stress in the case of higher current. [ABSTRACT FROM AUTHOR]

In recent years, significant changes have occurred in the field of three-dimensional printing (3D-printing) and it has been applied both in the production of prototypes and in regular production in the following sectors: architecture, construction, automotive, aircraft, biotechnology, fashion, etc. Different technologies for 3D-printing are proposed. Between them, the technology FDM (Fused Deposition Modelling) has the greatest application in the industry due to the low cost and simplified operations. This technology is suitable for 3D-printing of various polymers (PET, ABS, PLA, PETG, etc.), which after preliminary treatment can be metallised by electroless deposition in order to obtain an even metal coating. The present paper describes investigations of some properties of nickel or copper coatings, electroless deposited from two kinds of solutions on 3D-printed and on cast under pressure ABS samples. For deposition of electroless nickel or copper coatings with good adhesion, the influence of the pre-treatment operations was also evaluated in both cases upon deposition on 3D-printed ABS samples with different resolutions (0.8 or 0.25 mm,) and on cast under pressure ABS samples. The thickness of the deposited layers was determined gravimetrically; the morphology and the elemental composition of the layers were examined by SEM or EDS, respectively; the surface roughness of the ABS samples was measured by AFM, and the adhesion of the metal layers was evaluated by a standard test with an adhesive tape (type Test-Method ASTM D 3359-83). [ABSTRACT FROM AUTHOR]

The paper aims to determine the mechanical properties of the adhesive joints made with acrylic pressure-sensitive adhesives. Two types of double-sided acrylic pressure-sensitive adhesive tapes are used. Three construction materials are used to prepare the adhesive joints: structural steel sheet (C45), aluminium alloy sheet (EN-AW 5754), and titanium sheet (Grade 2). Strength tests of adhesive joints made with the pressure-sensitive adhesive tapes are carried out both after conditioning time at room temperature (23 °C) and subjected to thermal shocks (500 cycles: +60 °C / -40 °C). Strength tests are carried out based on the DIN EN 1465 standard on a Zwick/Roell Z150 testing machine. The main conclusion from the tests carried out was the positive effect of thermal shocks on the mechanical strength of joints bonded with pressure-sensitive adhesive tape. [ABSTRACT FROM AUTHOR]

Increasing heat transfer in heat exchangers remains an important research topic for industrial and residential applications. The usage of passive techniques remains a reference due to the lower costs, however, increasing the heat transfer in laminar flow with low-pressure loss remains a challenge. The objective of this paper is to perform a constrained optimisation of a twisted-tape inside a circular tube at low Reynolds number. Twisted tape pitch (P), length (L), translate (T), and twisted tape radius (R1 and R2) were submitted to optimisation. The flow is steady-state, laminar and incompressible. The NSGA-II is the method used for the optimisation procedure. The optimisation process found an optimal twisted-tape geometry with an asymmetric shape for both Reynolds numbers, corresponding to a global heat transfer increase of approximately 90% for Reynolds number 300 and 170% for Reynolds number 600, while for symmetric twisted-tape with ratio 4 (R4) is 57% and 52%, respectively. [ABSTRACT FROM AUTHOR]

When calculating the AC loss of REBa2Cu3O7−x (REBCO, RE = rare earth) coated conductor cable with stacked geometry, it is often considered that the tapes in the cable is perfectly stacked (there is no transverse misalignment of the tapes). However, the actual stacked cable will have transverse misalignment. The influence of transverse misalignment of tapes on the AC loss of the whole cable needs to be studied in order to understand the actual situation. In this paper, the 2-D H formulation calculated the AC loss of the cable with 10 tapes stacked in three cases. In the first case, the cables are perfectly stacked without lateral misalignment between the tapes. In the second case, the tapes of the cable are oblique to one side. In the third case, the tapes are disordered with each other. The result shows that under the transport current at 50 Hz, when the transport current is less than 0.75Ic0, the transport loss of the cable with obliquely stacked cable is more than the perfectly stacked cable, and when the transport current is greater than 0.75Ic0, the transport loss of the perfectly stacked cable is slightly larger than the obliquely stacked cable. Moreover, the transport loss of disorderly stacked cable is more than perfectly stacked cable at 50 Hz. When the transport current amplitude and the misalignment distance between the tapes in the cable are constant, the transport loss of obliquely stacked cable and disorderly stacked cable relative to perfectly stacked cable both increases first and then decreases as the frequency increases. Under the 50 Hz magnetization field, the magnetization loss of the perfectly stacked cable is less than the cables with oblique misalignment and disorder misalignment. When the amplitude of the external magnetic field and the misalignment distance between the tapes in the cable are constant, the magnetization loss of obliquely stacked cable and disorderly stacked cable relative to perfectly stacked cable also increased first and then decreased as the frequency increased. [ABSTRACT FROM AUTHOR]

Hypothesis: To test the efficacy of adhesive paper tape in the closure of clean-contaminated wounds following elective colorectal resection. Design: A prospective, nonrandomized controlled study. Setting: A medical center that offers a mixture of primary, secondary, and tertiary care services. Patients: The group undergoing skin closure with paper tape (PT group) consisted of 150 patients. The group undergoing skin closure with interrupted suture (IS group) also comprised 150 patients. All 300 patients underwent elective colorectal resection in 1997. Main Outcome Measures: The duration of skin closure, wound complication rate, and cosmetic appearance of the scar at 6 months after operation were compared using the χ[sup 2]test or t test. Results: The mean ± SD average duration of skin closure was 116 ± 23 seconds for the PT group and 457 ± 64 seconds for the IS group (P<.01). The wound complication rate was 3.3% (3 cases with wound infection; 2 with wound separation) for the PT group and 3.3% (5 cases with wound infection) for the IS group (P = 1.0). No significant differences were found between the narrowest width (mean ± SD, 2.2 ± 0.9 mm vs 2.3 ± 1.0 mm) and widest width (mean ± SD, 4.7 ± 2.0 mm vs 4.3 ± 1.8 mm) of scar formation between the 2 groups at 6 months after the operation. Ninety-eight percent of patients in the PT group reported satisfaction with their scar, compared with 92% in the IS group (P = .03). Conclusion: Compared with the traditional suture method, paper tape closure in the treatment of clean-contaminated wounds was less time consuming and produced greater patient satisfaction with no increased rate of wound complications. [ABSTRACT FROM AUTHOR]

Copyright of Silicone Material is the property of Silicone Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Government environment is the main determinant in attracting private investment into public–private partnership (PPP) projects, especially in developing countries. Red tape, an indicator of a government's efficiency, plays a critical role in private investment in PPP projects. Reasonable levels of red tape can enhance government transparency and promote private investment, while excessive red tape usually represents low governance efficiency and imposes further risk on private investors. This article explores how developing countries’ red tape affects private investment in PPP projects by examining the moderating effect of corruption. Analyzing a database of 308 PPP projects in 111 developing countries, the study reveals an inverted U-shaped relationship between red tape and private investment. Corruption weakens the positive relationship between red tape and private investment at low levels of red tape and mitigates their negative relationship at high levels. The study integrates the inconsistent results of previous research that postulated either a positive or negative relationship between red tape and private investment by proposing a nonlinear model. It also theorizes the moderating effect of corruption based on real management practice and illustrates its mechanism in absorbing private investment in PPP projects. [ABSTRACT FROM AUTHOR]

Based on the background of the Line F2-3 interval tunnel section of Jiujiawan in Urumqi Subway Line 1, this paper carries out the model test research on the antibreaking technology of the reducing dislocation layer in the tunnel section of the stick-slip fracture. The antibreaking effect of different locations and number of reducing dislocation layers in tunnel engineering is analyzed in this paper. The results show that when the double reducing dislocation layer, respectively, set between the surrounding rock and the primary support, and the primary support and the secondary lining, the antibreaking effect is the best. It is recommended to use this scheme for antibreaking design. The research results can provide reference for antibreaking design of traffic tunnels in active fault zones. [ABSTRACT FROM AUTHOR]

Purpose: Lead frame tape is a crucial support for lead frames in the IC assembly process. The tape residue on the quad flat non-leaded (QFN) could result in low reliability and failure in electrical conductivity tests. The tape residue would affect overall performance of the chips and contribute to low pass yield. The purpose of this paper is to present an in-depth study of tape residue and factors that may affect it. Design/methodology/approach: An experiment using lead frame and tapes from three manufacturers with two types of die bond adhesives, namely, die attach film (DAF) and wafer back coating (WBC), was conducted. Copper (Cu) wire bonding and die bonding performances were measured in terms of process capability, stitch bond strength and die attach strength. Findings: Results showed that no tape residue was observed on the thermoplastic adhesive-based lead frames manufactured by Hitachi after the de-taping process because of the tape's thermoplastic adhesive properties. Originality/value: This paper studies the occurrence of tape residue and a viable solution for it through the correct process optimization and combination of semiconductor manufacturing materials. Factors that may affect tape residue have also been studied and further research can be done to explore other options in the future as an alternate solution. [ABSTRACT FROM AUTHOR]

Seafloor mapping and vertical deformation monitoring are important for a gas hydrate exploitation. Due to the complexity of the marine environment and the difficulty of the seafloor operation, an in situ seafloor mapping and high-resolution vertical deformation monitoring simultaneously are big challenges. This paper describes an experimental research on an in situ system for a seafloor mapping and vertical deformation monitoring based on an elastic steel tape, along which an array of nine-axis microelectromechanical system (MEMS) sensors is arranged. The tape can measure both the motion of the bend and the twist. The MEMS sensor consists of an accelerometer, a gyroscope, and a magnetometer. The Euler angles obtained from the nine-axis MEMS sensor can be converted to a relative rotation matrix, showing the amount of the bend and the twist, and the curved shape of the tape can be calculated. Based on this concept, multitapes are used for the seafloor mapping and vertical deformation monitoring. To assess the monitoring system, a lab scale experiment in a water tank is carried out. The results demonstrate the feasibility of the proposed system for the seafloor mapping and deformation monitoring. [ABSTRACT FROM AUTHOR]

Accurate peeling off and transferring of microchips play a critical role in LED die sorting technology. Generally, sorting efficiency of more than 36 KUPH, and an alignment deviation less than 1 mil ($25.4~\mu \text{m}$) is required. High precision position control and cooperation of multifactors should be implemented precisely. Among all the factors, the film deformation is an important one. As the sorting proceeds, dies are peeled off from substrates one by one, and the adhesive substrate is penetrated through a hole each time. As the number of stripped chips increases, viscoelastic deformation of tape surface takes place and tiny position shift of die adhered on tape arises. This shift may cause a negative impact on the peeling process. In this paper, linear viscoelastic deformation impact is tested with well-designed experiments. To evaluate the effect of tape deformation accurately for sorting the performance, stochastic Petri net model of the transferring system with dual-independent arms is formulated to analyze the influence of factors. On this basis, strategy on coordinating motion control and scheduling is proposed, rational velocity section is planned, and the active position compensation of supply platform is set, so that the die can be peeled off correctly and efficiently. Finally, to improve sorting performance, methods on active compensation of aligning platform are proposed and proven effective by an experimental validation. [ABSTRACT FROM AUTHOR]

Second-generation high-temperature superconducting (HTS) tapes strongly rely on the substrate material, in many cases Hastelloy C276 (“H-C276”). In order to ameliorate performance (and reduce the price) of superconducting tapes, replacement of H-C276 has been investigated. In this paper, the potential of the readily available austenitic stainless steels X2CrNiMo17-12-2 (“CrNiMo”) and X11CrNiMnN19-8-6 (“CrNiMnN”) as substrates is assessed. It was found that CrNiMnN is not suitable as a replacement for H-C276. Tensile stresses occurring at elevated temperatures during the HTS tape production result in plastic deformation of the CrNiMnN substrate. In the case of CrNiMo, however, plastic deformation was not observed after processing of the HTS tape. Electrical losses as a result of alternating currents beyond those of H-C276 did not occur due to the paramagnetic nature of CrNiMo. It is demonstrated that, for the very same processing parameters, HTS films deposited on electrochemically polished and buffered CrNiMo substrates exhibit similarly high critical current densities as on polished and buffered H-C276 substrates. The application of CrNiMo stainless steel reduces substrate costs considerably. More importantly, tapes processed on CrNiMo substrates withstand higher tension strains with respect to the reduction of the critical current compared to H-C276 substrates. This effect is interpreted to be a result of the matching coefficients of thermal expansion of the HTS layer and CrNiMo, resulting in lower residual tensile stress in the HTS layer after processing. [ABSTRACT FROM AUTHOR]

With current developments underway at the University of Houston, 4× high‐temperature superconducting (HTS) yttrium barium copper oxide (YBCO) tapes are expected to reach a fourfold critical current density improvement at 30 K and 3 T as part of an Advanced Research Projects Agency‐Energy (ARPA‐E)‐sponsored project. The impetus for this project is to develop and deploy cost‐effective direct drive HTS generators for large offshore wind turbine generators. The improved conductor performance of 4× tapes over 1× tapes is projected to allow for a significant reduction in the amount of HTS tapes required to generate the excitation field and, thus, lead to a reduction of the overall generator cost. It was, however, deduced from simulation results that conventional methods of rotor field enhancement using rotor iron makes 1× conductor competitive enough compared with 4× conductors; hence, commercially available YBCO tapes can provide all the energy density requirements to make wind turbines a competitive energy resource based on energy forecasts. This paper is a presentation of design and optimization work to find the best generator topology from the point of view of both machine design and electricity supply. The generators are numerically modeled and simulated using 1× and 4× YBCO HTS conductors on either or of both the rotor and stator side of the generators. [ABSTRACT FROM AUTHOR]

In DC systems, DC resistive type superconducting fault current limiters (R-SFCLs) can respond within a few hundred milliseconds and limit the fault current to a very low level to protect the power equipment in DC systems. The main part of R-SFCLs are superconducting tapes. When short-circuit faults occur in the system, the superconducting tapes will quench and become a large quenched resistor to limit the fault current. The surrounding magnetic fields and the magnetic fields caused by the superconducting tapes itself influence the quench characteristics of the superconducting tapes of R-SFCLs. Thus, the current limiting characteristics of R-SFCLs will also be affected. Until present, very few studies have investigated the effects of magnetic fields on quench characteristics of superconducting tapes for DC R-SFCL. The objective of this paper is to obtain the effects of magnetic fields on quench characteristics of superconducting tapes for DC R-SFCL. Two different kinds of YBa2Cu3O7-δ (YBCO) tapes are studied under a permanent magnetic field of 0, 42.4, 75.9, 122.9 mT, respectively. One is from Shanghai Superconductor Technology Co., Ltd., Shanghai, China, type ST-12-L (named SC_SH) and the other is from American Superconductor Inc. Boston, MA, USA, type 8602 (named SC_8602). The research results show that the magnetic fields influence both the amplitude and the rising rate of the quenched resistance of an SC_SH tape. Under the same magnetic field, both the speed of quenching and the quenching resistance of SC_SH tape are larger than them of SC_8602 when the prospective current exceeds 800 A. Thus SC_SH tape can limit the fault current faster and to a lower level. [ABSTRACT FROM AUTHOR]

Quench and recovery characteristics are the most important characteristics of dc resistive type superconducting fault current limiters (SFCLs). In the normal state, the superconducting tapes of SFCLs stay in superconducting state without power loss. However, if there is a thermal disturbance energy impact to the superconducting tapes, the tapes may be quenched, and sometimes even break once their temperature is too high. After the thermal disturbance, the tapes may recover to superconducting state again. A numerical analysis method was proposed to analyze quench propagation and recovery characteristics of the YBa2Cu3O7-δ tapes based on thermal conduction theory. The objective of this paper is to obtain the influencing factors such as magnitude of thermal disturbance, transport current, material of the stabilized layer and cooling on quench, and recovery properties of dc resistive type SFCL. Numerical analysis results show that the temperature and voltage of the tape increased while the transport current through the tape and the magnitude of thermal disturbance increased. The quench propagation velocity was higher and the recovery time was shorter for copper stabilized layers than stainless steel stabilized layers. [ABSTRACT FROM AUTHOR]

Magnetization loss is an important parameter in the design of high-temperature superconducting (HTS) power devices. It is produced under the external alternating magnetic fields. In previous work, for the purpose of reducing the loss, our group proposed and fabricated a novel soldered-stacked-square (3S) HTS wire with a cross-section of 1 mm × 1 mm. In this paper, the magnetization losses of the 3S wire are investigated numerically. First, numerical and theoretical losses in single HTS tapes are compared and their consistence proves the reliability of the numerical model. Also, the losses in tapes of different widths are evaluated, which shows the 1-mm tapes have less magnetization losses under perpendicular field. Moreover, the numerical model for estimating losses in 3S wires has also been built. According to a series of calculation and comparison, the 1-mm stacked wires have less losses than those wider stacked wires under perpendicular field. Besides, considering the practical application of HTS power devices, angular dependence of the loss in 3S wires containing one HTS tape is studied as well. The results indicate the loss increases with the increase of the angle with respect to the wire surface. [ABSTRACT FROM AUTHOR]

This paper studies the current limiting behavior based on an air-core high-temperature superconducting transformer (HTST) and a group of inductor–capacitor series resonant limiters. The air-core HTST is composed of four same double-pancake type high-temperature superconducting coils made up of Bi-2333/Ag tape, and both of primary and secondary windings include two series superconducting coils. It plays the roles of inductive fault current limiting and transformation impedance; in addition, the magnetic flux saturation can also be avoided. Meanwhile, the inductor and capacitor series with the secondary winding of the air-core HTST in series resonance state are the conventional devices. The influence of them on the circuit can almost be ignored, because they are in series resonant state in normal operation. While the fault current appeared in the primary circuit, it will be limited by the impedance of the air-core HTST and the inductor without quench (the inductor and capacitor would quit the series resonant state). According to the preliminary experiment carried out in our laboratory, this superconducting current limiting module can operate as expected, and its behavior is satisfactory. [ABSTRACT FROM AUTHOR]

• Forensic-voice-comparison systems that output numeric likelihood ratios. • Guidance on how to validate in the context of a case. • Developed via a consensus process. Since the 1960s, there have been calls for forensic voice comparison to be empirically validated under casework conditions. Since around 2000, there have been an increasing number of researchers and practitioners who conduct forensic-voice-comparison research and casework within the likelihood-ratio framework. In recent years, this community of researchers and practitioners has made substantial progress toward validation under casework conditions becoming a standard part of practice: Procedures for conducting validation have been developed, along with graphics and metrics for representing the results, and an increasing number of papers are being published that include empirical validation of forensic-voice-comparison systems under conditions reflecting casework conditions. An outstanding question, however, is: In the context of a case, given the results of an empirical validation of a forensic-voice-comparison system, how can one decide whether the system is good enough for its output to be used in court? This paper provides a statement of consensus developed in response to this question. Contributors included individuals who had knowledge and experience of validating forensic-voice-comparison systems in research and/or casework contexts, and individuals who had actually presented validation results to courts. They also included individuals who could bring a legal perspective on these matters, and individuals with knowledge and experience of validation in forensic science more broadly. We provide recommendations on what practitioners should do when conducting evaluations and validations, and what they should present to the court. Although our focus is explicitly on forensic voice comparison, we hope that this contribution will be of interest to an audience concerned with validation in forensic science more broadly. Although not written specifically for a legal audience, we hope that this contribution will still be of interest to lawyers. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Unlike conventional forensics, digital forensics does not at present generally quantify the results of its investigations. It is suggested that digital forensics should aim to catch up with other forensic disciplines by using Bayesian and other numerical methodologies to quantify its investigations' results. Assessing the plausibility of alternative hypotheses (or propositions, or claims) which explain how recovered digital evidence came to exist on a device could assist both the prosecution and the defence sides in criminal proceedings: helping the prosecution to decide whether to proceed to trial and helping defence lawyers to advise a defendant how to plead. This paper reviews some numerical approaches to the goal of quantifying the relative weights of individual items of digital evidence and the plausibility of hypotheses based on that evidence. The potential advantages enabling the construction of cost-effective digital forensic triage schemas are also outlined. The absence of quantified results from digital forensic investigations, unlike those of conventional forensics, is highlighted. A number of approaches towards quantitative evaluation of the results of digital forensic investigations are reviewed. The significant potential benefits accruing from such approaches are discussed. [ABSTRACT FROM AUTHOR]

Cable-in-conduit conductors comprised of twisted stacks of high-temperature superconducting (HTS) tapes constitute a very promising technology by virtue of their easy manufacturing process, flexibility capabilities, and high current densities. In a cable, the current distribution among tapes is one of the key parameters affecting the cable performances. The distribution of current is affected mainly by the self-field configuration (ultimately related to the cable layout) and the termination resistances. In this paper we present a 2D finite element (FE) model, based on the T-A formulation, which computes the magnetic field and current distribution in stacked tapes. This model has been used to describe the experimental V–I results obtained in cables in which different current distributions among tapes are expected. The first case refers to V–I curves of stacks of HTS tapes inserted into ducts formed in the extruded aluminium cylindrical core for a straight cable. The excellent agreement between the experimental findings and the simulation results can be explained in terms of uniform current distribution within the tapes stack, up to the superconducting to normal transition. The second sample, an Al-slotted core Cable-In-Conduit-Conductor, has been bent down to a radius of 0.15 m, and from the measured V–I characteristic of each individual tape, a different tape degradation depending on the tape position within the stack was recorded. The model is able to reconstruct the V–I of the stacks from the characteristic curves of the individual tapes with a satisfactory agreement. The finite element analysis reveals non-uniform current distribution among the tapes, which could expose the cable to a potentially irreversible damage during operation. The proposed FE model constitutes a useful tool for the analysis and predictions of HTS CIC conductor performances and represents a suitable basis for the implementation of more complex models aimed at the design of specific and large applications of this conductor in the next future. [ABSTRACT FROM AUTHOR]

Previous studies of test coils have demonstrated the high thermal and electrical stability of no-insulation (NI) high temperature superconducting (HTS) coils thanks to the presence of turn-to-turn current paths. These turn-to-turn current paths in a NI coil are significantly influenced by the contact resistivity. In practice, it is very challenging to measure the contact resistivity of a NI coil by direct experiments of short samples, since the contact resistivity of superconducting tapes is influenced by surface roughness and tolerance, stress, temperature etc. A proper simulation model is needed to investigate the contact resistivity of the NI coils with dedicated experiments. Hence, in this paper a distributed circuit model is employed. This model, implemented in Matlab 2018a, considers the local contact resistivity, self and mutual inductance, and HTS resistance, which depends on the supplied current, magnetic field and temperature. To validate the model, experimental results from literature, including sudden discharge, and charge–discharge processes, are employed and the results from simulations are consistent with experimental results. Then the model is used to investigate the equivalent contact resistivity of a 157-turn NI coil. Through the comparison of simulated and experimental results, it is found that the contact resistivity of the NI coil has an inhomogeneous distribution. When the current changes with different speeds, ramping rates or frequency, a different number of turn-to-turn contacts carries radial current. Since the turn-to-turn contacts have different contact resistivity, the equivalent contact resistivity calculated from sudden discharge cannot be used in simulations to reproduce all the experimental data. [ABSTRACT FROM AUTHOR]

Microfluidic chips have shown their potential for applications in fields such as chemistry and biology, and 3D printing is increasingly utilized as the fabrication method for microfluidic chips. To address key issues such as the long printing time for conventional 3D printing of a single chip and the demand for rapid response in individualized microfluidic chip customization, we have optimized the use of DLP (digital light processing) technology, which offers faster printing speeds due to its surface exposure method. In this study, we specifically focused on developing a fast-manufacturing process for directly printing microfluidic chips, addressing the high cost of traditional microfabrication processes and the lengthy production times associated with other 3D printing methods for microfluidic chips. Based on the designed three-dimensional chip model, we utilized a DLP-based printer to directly print two-dimensional and three-dimensional microfluidic chips with photosensitive resin. To overcome the challenge of clogging in printing microchannels, we proposed a printing method that combined an open-channel design with transparent adhesive tape sealing. This method enables the rapid printing of microfluidic chips with complex and intricate microstructures. This research provides a crucial foundation for the development of microfluidic chips in biomedical research. [ABSTRACT FROM AUTHOR]

Wood-derived materials have been utilized to develop filtration membranes for sustainable oil/water separation. However, it remains a significant challenge to manufacture durable wood-based membranes with high efficiency and ultra-high flux by simple methods. Herein, we report a facile strategy to fabricate a novel superhydrophobic hybrid wood membrane (PDMS@MOF-199/WS) with ultrahigh-flux and excellent oil/water separation performance. Firstly, copper-based metal organic frameworks (MOF-199) were in situ grown on the TEMPO-oxidized wood sponge (TO-WS) substrate to construct a hierarchical micro-nano structure with internal inherent microchannels. Secondly, a super-wetting surface was formed through soaking in polydimethylsiloxane (PDMS) and heat treatment. Remarkably, the water contact angle (WCA) of PDMS@MOF-199/WS could reach 163° and the oil contact angle (OCA) was around 0°, which remained stable over a long period of ultrasonic treatment and tape peeling. More importantly, the as-prepared modified wood membrane can efficiently separate a wide range of immiscible oil/water mixtures, solely by tiny gravity, with ultra-high flux of 10,385 L m−2 h−1 (carbon tetrachloride/water) and separation efficiency of 99.6% (n-hexane). Furthermore, this novel membrane can also effectively separate surfactant-stabilized water-in-oil emulsions with an efficiency of as high as 97.8%. Meanwhile, the hybrid membrane displayed exceptional reusability, maintaining a high-flux of 8599.6 L m−2 h−1 and retaining WCA at 154.8° after 12 cycles. Our results demonstrate that the synergetic impact of MOF-199 and PDMS as a means of encoding on-surface wettability substantially improved the separation efficiency. This work opens a new avenue for the design of functional wood-derived filtration membranes for the ultrahigh flux oil–water separation. [ABSTRACT FROM AUTHOR]

Objective: To identify adhesive renal venous tumor thrombus (RVTT) of renal cell carcinoma (RCC) by contrast-enhancement CT (CECT). Materials and methods: Our retrospective study included 53 patients who underwent preoperative CECT and pathologically confirmed RCC combined with RVTT. They were divided into two groups based on the intra-operative findings of RVTT adhesion to the venous wall, with 26 cases in the adhesive RVTT group (ARVTT) and 27 cases in the non-adhesive group (NRVTT). The location, maximum diameter (MD) and CT values of tumors, the maximum length (ML) and width (MW) of RVTT, and length of inferior vena cava tumor thrombus were compared between the two groups. The presence of renal venous wall involvement, renal venous wall inflammation, and enlarged retroperitoneal lymph node was compared between the two groups. A receiver operating characteristic curve was used to analyze the diagnostic performance. Results: The MD of RCC and the ML and MW of the RVTT were all larger in the ARVTT group than in the NRVTT group (p = 0.042, p < 0.001, and p = 0.002). The proportion of renal vein wall involvement and renal vein wall inflammation were higher in the ARVTT group than in NRVTT groups (both p < 0.001). The multivariable model including ML and vascular wall inflammation to predict ARVTT could achieve the best diagnostic performance with the area under the curve, sensitivity, specificity, and accuracy of 0.91, 88.5%, 96.3%, and 92.5%, respectively. Conclusion: The multivariable model acquired by CECT images could be used to predict RVTT adhesion. Clinical relevance statement: For RCC patients with tumor thrombus, contrast-enhanced CT could noninvasively predict the adhesion of tumor thrombus, thus predicting the difficulty of surgery and contributing to the selection of an appropriate treatment plan. Key Points: • The length and width of the tumor thrombus could be used to predict its adhesion to the vessel wall. • Adhesion of the tumor thrombus can be reflected by inflammation of the renal vein wall. • The multivariable model from CECT can well predict whether the tumor thrombus adhered to the vein wall. [ABSTRACT FROM AUTHOR]

The self‐curable epoxidized polymeric fraction of the natural gum "Chios mastic" (Pistacia lentiscus L.) gum is used as a matrix to produce sustainable particulate composite adhesives and further to manufacture lap joints. Olive pit powder and cotton flocks are used as reinforcements, each for a range of contents. Mixed‐modulus‐joint and Nanotube‐coated‐adherend special manufacturing techniques are also applied to further improve shear properties, reduce shear stress concentrations, or increase the adhesive and the adherend cohesion. 2% (w/w) Aluminum and 2% (w/w) olive pit reinforcements achieve an increase in shear strength of 14.19% and 12.26%, respectively, while cotton flocks‐ initially of lower performance as well as pieces of cotton fabric, are used to make joints according to the Nanotube‐coated‐adherend technique achieving an increase in shear strength of 102.1% and 84.91%, respectively. The obtained experimental results demonstrate the potential of the epoxidized polymer fraction of Chios natural mastic to produce useful sustainable particulate epoxy composite adhesives and double‐sided adhesive tapes. [ABSTRACT FROM AUTHOR]

In a simple and interesting theory of ultratough peeling of an elastic tape from a viscoelastic substrate, Afferrante and Carbone find that there are conditions for which the load for steady state peeling could be arbitrarily large in steady state peeling, at low angles of peeling - what they call "ultratough" peeling (Afferrante, L., Carbone, G., 2016, The ultratough peeling of elastic tapes from viscoelastic substrates, Journal of the Mechanics and Physics of Solids, 96, pp.223-234). Surprisingly, this seems to lead to toughness enhancement higher than the limit value observed in a very large crack in an infinite viscoelastic body, possibly even considering a limit on the stress transmitted. The Afferrante-Carbone theory seems to be a quite approximate, qualitative theory and many aspects and features of this "ultratough" peeling (e.g. conformity with the Rivlin result at low peel angles) are obtained also through other mechanisms (Begley, M.R., Collino, R.R., Israelachvili, J.N., McMeeking, R.M., 2013, Peeling of a tape with large deformations and frictional sliding, Journal of the Mechanics and Physics of Solids, 61(5), pp. 1265-1279) although not at “critical velocities”. Experimental and/or numerical verification would be most useful. [ABSTRACT FROM AUTHOR]

The development of flexible sensors based on laser-induced graphene (LIG) has recently attracted much attention. It was commonly generated by laser-ablating commercial polyimide (PI). However, the weak mechanical extensibility of PI limits the development and diversified applications of LIG-based sensors. In this work, we adopted medical polyurethane (PU) tapes to peel off the LIG generated on PI and developed flexible and wearable sensors based on the proposed LIG/PU composite structure. Compared with other methods for LIG transfer, PU tape has many advantages, including a simplified process and being less time-consuming. We characterized the LIG samples generated under different laser powers and analyzed the property differences introduced by the transfer operation. We then studied the impact of fabrication mode on the strain sensitivity of the LIG/PU and optimized the design of a LIG/PU-based strain sensor, which possessed a gauge factor (GF) of up to 263.6 in the strain range of 75–90%. In addition, we designed a capacitive pressure sensor for tactile sensing, which is composed of two LIG/PU composite structures and a PI space layer. These LIG flexible devices can be used for human motion monitoring and tactile perception in sports events. This work provides a simple, fast, and low-cost way for the preparation of multifunctional sensor systems with good performance, which has a broad application prospect in human motion monitoring. [ABSTRACT FROM AUTHOR]

Thermoplastic tapes are commonly processed by the rapid and efficient stamp forming process. During this forming process, the individual unidirectional tapes of the composite stack move relative to each other and relative to the surface of the tool while being in contact with the corresponding counterpart. As a result, the material exhibits a certain resistance against this movement, which is generally dependent on velocity, normal pressure, and temperature. Therefore, this work investigates the ply/tool and ply/ply slippage of unidirectional, carbon fiber reinforced polycarbonate tapes and provides an alternative implementation of the experimentally observed slippage using cohesive zone modeling. The backbone of the modeling approach is an experimental data set obtained from pull-through experiments. In comparison to common slippage or friction theories, the force plateau of thermoplastic UD tapes at elevated temperatures is observed after an initial force peak has been overcome. For both configurations, ply/tool and ply/ply, a reduction of the initial force peak was observed for increasing temperature. Furthermore, the resulting plateau force value is at least 36% higher in the ply/ply configuration compared to the ply/tool configuration at 200 °C. The derived cohesive zone model allows for accurate modeling of the initial force peak and the plateau. [ABSTRACT FROM AUTHOR]

Poly(silsesquioxane)‐based polymer‐derived ceramics (PDCs), may be manufactured by a great variety of processes and process combinations leading to ceramic parts seven with high functionality. Advantage of the use of poly(silsesquioxane)s as starting materials with a defined amount of oxygen is that low‐temperature‐processing steps such as shaping and cross‐linking may be carried out in air, and a disadvantage often discussed is a maximum service temperature below 1200 °C. In this article, the focus is set to PDC tapes, coatings, tailored surfaces, and tailored porosity. And, a rough distinction is made between materials pyrolyzed below 1200 °C and far above 1200 °C. The later provides porosity formed by high‐temperature reactions between particulate fillers and the ceramic residue from pyrolysis. [ABSTRACT FROM AUTHOR]

This paper presents the production and the characterization of the multi-walled carbon nanotube (MWCNT) printed flexible temperature sensors for high-precision reading in temperature sensing applications. The temperature sensor was fabricated using the inkjet printing method by depositing carbon nanotube (CNT) ink on soft taffeta fabric. An aqueous CNT-based conductive ink was formulated for the inkjet printing process. A translucent polyurethane (PU) welding tape was used as an encapsulation layer on the surface of the sensors to protect sensors from various environmental effects during usage and testing. The fabricated sensors function as thermistors, as the conductivity increases with temperature linearly. The performances of differently patterned three temperature sensors were compared. The highest obtained temperature coefficient of resistance (TCR) and the thermal index are −1.04%/°C and 1135 K, respectively. The fabricated sensors possess a high-temperature sensitivity between room temperature and 50 °C and perform better than the typical commercial platinum temperature sensors and most of the recently reported CNT-based temperature sensors in the literature. [ABSTRACT FROM AUTHOR]

Microbial resistance to currently available antibiotics poses a great threat in the global fight against infections. An important step in determining bacterial antibiotic resistance can be selective DNA sequence capture and fluorescence labeling. In this paper, we demonstrate the fabrication of simple, robust, inexpensive microfluidic devices for DNA capture and fluorescence detection of a model antibiotic resistance gene sequence. We laser micromachined polymethyl methacrylate microchannels and enclosed them using pressure-sensitive adhesive tapes. We then formed porous polymer monoliths with DNA capture probes in these microchannels and used them for sequence-specific capture, fluorescent labeling, and laser-induced fluorescence detection of picomolar (pM) concentrations of synthetic and plasmid antibiotic resistance gene targets. The relative fluorescence for the elution peaks increased with loaded target DNA concentration. We observed higher fluorescence signal and percent recovery for synthetic target DNA compared to plasmid DNA at the same loaded target concentration. A non-target gene was used for control experiments and produced < 3% capture relative to the same concentration of target. The full analysis process including device fabrication was completed in less than 90 min with a limit of detection of 30 pM. The simplicity of device fabrication and good DNA capture selectivity demonstrated herein have potential for application with processes for bacterial plasmid DNA extraction and single-particle counting to facilitate determination of antibiotic susceptibility. [ABSTRACT FROM AUTHOR]

In this paper, we prove that a k-tape Minsky machine operating with time can be modeled by a three-tape Minsky machine in a time not exceeding . It is shown that multitape Turing machines can be modeled by three-tape Minsky machines with optimal word encoding. [ABSTRACT FROM AUTHOR]

Data on the physical characteristics of North African hashish are scarce. This article exploits hashish seizure data collected over an 8‐year period (2011–2018) in Algeria in order to establish a physical profile of North African hashish. The collected data were subjected to statistical analysis in order to characterize the three main forms in which North African hashish is packaged, namely hashish bags, hashish packets, and hashish units (slab bars). The study revealed that 82% of hashish bags weigh 25 kg that hashish bags are made either as a handbag or as a back bag that they are most often wrapped with woven plastic. Two hashish bag configurations were identified—Bag‐Packet‐Unit (79%) and Bag‐Unit (21%)—and 81% of the total studied bags featured logos. Hashish packets contain the units, which are wrapped with three to five different types of packaging to constitute packets of 0.5 kg (65%) or 1 kg (32%), with two different configurations including 100‐ or 250‐g units. Hashish packets are mainly covered with adhesive tape, and only 18% of them feature inscriptions. Hashish units are found in three different shapes: slab bar (most common), soap bar, and egg‐shaped bar. Sixty‐five percent of the North African hashish slab bars have a weight of 100 g; other weights are 250 g (20%), 90 g (10%), and 200 g (2%). Most of the 90–100 g units have a light brown color, and 200–250 g units are dark brown in color. Sixty‐four percent of hashish units contain logos. Five logo classes were identified: letters (37%), numbers (27%), symbols (23%), animals (11%), and, more recently, "paper logos" at just 2%, exclusively reserved for high‐quality hashish and entirely intended for the European market. The findings of this work allow for the establishment of a profiling platform of hashish seizures in this region and can be generalized to all countries that report this region as the primary source of seized hashish within their territory. [ABSTRACT FROM AUTHOR]