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Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology 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 Railway Construction Technology is the property of Railway Construction Technology 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.)

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology 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.)

In cold regions, the flow of outside air into a tunnel often causes freeze–thaw damage to the surrounding rock, and insulation methods are usually adopted to avoid this damage. In this study, the heat transfer in a multilayer tunnel structure that includes a rock layer, an initial lining, an insulation layer, and a secondary lining was investigated, and convection between the tunnel air and the inner surface of the tunnel lining was considered. A mathematical model describing the heat transfer process was established, and an analytical solution for the temperature field was developed using Duhamel's principle and the separation-of-variables method. The model and the solution were verified by comparing the computational results of the analytical solution with the computational results and in situ measurements available in the literature. By treating the minimum temperature of the inner surface of the surrounding rock as a function of the insulation thickness, a procedure to determine the minimum insulation thickness that ensures no freeze–thaw damage to the surrounding rock was developed based on the analytical solution using the bisection method. Computational examples were presented, and the effects of different factors on the minimum temperature of the inner surface of the surrounding rock and minimum insulation thickness were investigated. [ABSTRACT FROM AUTHOR]

Under the effect of long-term low temperature environment, the railway tunnel lining in the cold regions is prone to cracking, peeling and other diseases, which effects the safety and durability of the structure. This paper analyzes the current situation and existing problems of relevant construction standards for frost-resistance and protection of tunnel lining in the cold regions, and puts forward the main contents that need to be studied and improved from the aspects of design and construction. Combined with engineering examples, this paper further discusses the main design criterion of the reinforcement parameters, expansion joint setting and waterproof construction technology of insulation layer of the tunnel lining in the cold regions, and puts forward the computing method for the length of formwork of the tunnel lining in cold regions. The results show that: (1) the longitudinal reinforcement of the lining in the frost-resistant section should be "fine and intensive" to improve the anti-crack ability of the structure; (2)"Zero joint width" expansion joint will reduce the temperature stress of tunnel in cold region under certain conditions; (3)The waterproof construction technology of " spray type" polyurethane insulation board can effectively improve the insulation capacity; (4) The annual average temperature of the tunnel zone should be taken as an important consideration factor for the temperature difference of the tunnel lining environment in the cold regions. The calculation results show that when the average temperature of the coldest month is -3~ - 8 ?, and the annual average temperature is 12~ 8 ?, the length of the lining formwork with a length of 12m can also meet the seasonal temperature difference requirements. [ABSTRACT FROM AUTHOR]

To protect pavement in cold regions, insulation layers have been used in pavement construction. The insulation layer blocks the heat exchange, resulting in different pavement temperature distributions at different layers. Pavements in cold regions are subject to frost heave, thaw weakening, and freeze–thaw cycling, and the moisture content of unbound materials is affected by the temperature of the pavement. Therefore, the base and subgrade temperature can affect the pavement performance, and the insulation layer influences the performance of the pavement. This work aims to demonstrate the capability of the machine learning method to predict the pavement temperature of the base and subgrade layers in the presence of insulation layers. Pavement temperature measured from sensors embedded in the pavement at the IRRF test road and environmental factors collected from a weather station were used to train machine learning models. The results obtained from machine learning models indicated that the air temperature and day of the year were the most robust input prediction parameters at each depth. Machine learning models outperformed the existing model and proved that it could be a method to improve pavement temperature prediction with insulation layers, especially when the base layer temperature is below 0°C. [ABSTRACT FROM AUTHOR]

Iron dust cores produced from insulated iron particles via the powder metallurgy pressure-forming process are suitable for small motor cores, reactor cores, and inductors because of their high shape flexibility. However, the dust core’s magnetic properties are inferior to those of conventional laminated cores because the insulation materials and silicon resins between iron particles to reduce eddy current losses degrade the magnetic properties of the core. Unfortunately, there is no researches of the iron dust cores without binders such as resin to improve the magnetic properties. Therefore, this paper investigates the magnetic properties of iron dust cores without binders. Assessments revealed that the dust core of gas-atomized iron powder with an average particle size of 49μmhad the best magnetic properties. On further assessments, while the insulation layer’s thickness was around 60 nm, the density of gas atomized iron powder core was over 7.6 g/cm3. At 50 Hz and 1 kHz, DC hysteresis iron losses and eddy current loss of 49μmgas atomized iron dust cores without a binder showed lower values than those of the conventional powder core with a binder.

To mitigate freeze-thaw damage in tunnels located in high-altitude cold regions, insulation layers are implemented to prevent the freezing of surrounding rocks. Currently, the selection of laying methods lacks a solid scientific basis, with the merits and demerits of various techniques remaining insufficiently evaluated. This study seeks to establish a scientifically grounded equilibrium between the anti-freezing efficacy and the construction impact of tunnel insulation in cold regions through the optimization of insulation design via numerical calculations. First, the advantages and disadvantages of the four insulation layer laying methods were summarized. Then, a multilayer media heat transfer model that accounts for the latent heat of phase change was developed, grounded in solid heat transfer and porous media heat transfer theories, and corroborated by typical case studies. Finally, taking Duolong tunnel as a case study, the insulation effect of various laying methods at different positions of the tunnel was analyzed based on the finite element method. The results show that the unfavorable position of the four laying methods is at the inverted arch of the tunnel, and the unfavorable time point occurs when the temperature rises from below 0℃ to above 0℃. Among the four laying methods, off-wall laying exhibits the superior insulation performance at tunnel vault, while sandwich laying has best insulation effect at the arch foot and inverted arch. The research results can provide reference and basis for the thermal insulation and anti-freezing design of tunnels in high-altitude cold regions.

Efficient thermal insulation materials considerably lower power consumption for heating and cooling of buildings, which in turn minimises CO2 emissions and improves indoor comfort conditions. However, the selection of suitable insulation materials is governed by several factors, such as the environmental impact, health impact, cost and durability. Additionally, the disposal of used insulation materials is a major factor that affects the selection of materials because some materials could be very toxic for humans and the environment, such as asbestos-containing materials. Therefore, there is a continuous research effort, in both industry and academia, to develop sustainable and affordable insulation materials. In this context, this work aims at utilising the packing industry wastes (cardboard) to develop an eco-friendly insulation layer, which is a biodegradable material that can be disposed of safely after use. Experimentally, wasted cardboard was collected, cleaned, and soaked in water for 24 h. Then, the wet cardboard was minced and converted into past papers, then cast in square moulds and left in a ventilated oven at 75 °C to dry before de-moulding them. The produced layers were subjected to a wide range of tests, including thermal conductivity, acoustic insulation, infrared imaging and bending resistance. The obtained results showed the developed material has a good thermal and acoustic insulation performance. Thermally, the developed material had the lowest thermal conductivity (λ) (0.039 W/m.K) compared to the studied traditional materials. Additionally, it successfully decreased the noise level from 80 to about 58 dB, which was better than the efficiency of the commercial polyisocyanurate layer. However, the bending strength of the developed material was a major drawback because the material did not resist more than 0.6 MPa compared to 2.0 MPa for the commercial polyisocyanurate and 70.0 MPa for the wood boards. Therefore, it is recommended to investigate the possibility of strengthening the new material by adding fibres or cementitious materials.

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials 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.)

The unreasonable setting of thermal insulation layer in high cold tunnels not only increases the maintenance cost of tunnels, but also weakens the anti-freezing and cold resistance of the tunnels. In order to optimize the setting of thermal insulation layer in an Alpine tunnel, relying on Dabanshan tunnel in Qinghai Province, three schemes of radial and longitudinal thermal insulation region of thermal insulation layer were adopted, and the temperature field of the surrounding rock was numerically analyzed. The results show that the uneven region scheme of 9 cm-8 cm-7 cm and 10 cm-9 cm-8 cm insulation layer can effectively reduce the freezing area of the lining and the surrounding rock, the freezing region at the tunnel entrance is significantly reduced, and there is no lining freezing region within the depth of 30–750 M. The research results can provide guidance for the partition wall setting of radial and longitudinal insulation layers of Alpine tunnels. In addition, it has considerable economic advantages for the reduction in engineering construction costs. [ABSTRACT FROM AUTHOR]

The major method used to reduce the magnetic loss of soft magnetic composites (SMCs) is to coat the magnetic powder with an insulating layer, but the permeability is usually sacrificed in the process. In order to achieve a better balance between low losses and high permeability, a novel photodecomposition method was used in this study to create a ZnO insulating layer. The effect of the concentration of diethyl zinc on the formation of a ZnO insulating film by photodecomposition was studied. The ZnO film was best formed with a diethyl zinc n-hexane solution at a concentration of around 0.40 mol/L. Combined with conventional coupling treatment processes, a thin and dense insulating layer was coated on the surface of iron powder in situ. Treating the iron powder before coating by photodecomposition led to a synergistic effect, significantly reduced core loss, and the effective permeability only decreased slightly. An iron-based soft magnetic composite with a loss value of 124 kW/m3 and an effective permeability of 107 was obtained at the frequency of 100 kHz and a magnetic field intensity of 20 mT. [ABSTRACT FROM AUTHOR]

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction 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.)

In this work, numerical simulation and experimental research were carried out on ablation mechanism of the first pulse (I pulse) insulation layer in a double-pulse solid rocket motor (SRM). Firstly, based on the internal thermal environment of the typical double pulse SRM, the internal flow field in combustion chamber of the double-pulse SRM with soft type pulse separation device (PSD) under the second pulse (Ⅱ pulse) working condition was numerically simulated. The results showed that the main reason for the difference of ablation in I pulse insulation layer was the difference of gas phase velocity. Secondly, based on the simulation analysis results, the experimental system for ablation of insulation layer was developed, and the ablation performance experiments under two gas phase velocities were carried out. It was found that a brittle carbonized layer had been formed on the surface of the insulation layer after the completion of I pulse work. In addition, at the beginning of Ⅱ pulse work, the suddenly generated gas flow made a denudation effect on the carbonized layer, which consumed a part of the carbonized layer. After the carbonized layer was peeled off, the gas flow continued to ablate the matrix of the insulation layer. Finally, the simulation analysis of the ablation process of the insulation layer under two gas phase velocities was carried out. The results showed that the velocity of the fuel gas is the main factor affecting the ablation rate of the insulation layer, which was consistent with the experimental results. It is proven that the model can be used to estimate the ablation amount of insulation of solid rocket motor. The conclusion can provide a significant reference for the internal heat protection design of the double-pulse SRM. [ABSTRACT FROM AUTHOR]

We developed photosensitive material for Mini/Micro LED display. The material is negative tone type and alkaline developable. Minimum resolution of the material is 10 μm with 10 μm thickness, and taper angle is approximately 80°. The material has high transparency and good heat resistance. Transparency of 10 μm thickness cured film is more than 90% at 400 nm, Tg of cured film is over 250°C. And the material has durability against blue light (405 nm). After radiation of blue light at 50°C for 400 hrs, the material has no transparency loss and no film thickness loss. [ABSTRACT FROM AUTHOR]

ND-GAr is one of three detector systems in the design of the DUNE Near Detector complex, which will be located on the Fermilab campus, sixty meters underground and 570 m from the source of an intense neutrino beam. ND-GAr will consist of a cylindrical 10-bar gaseous Argon Time Projection Chamber (TPC) and a surrounding sampling electromagnetic calorimeter embedded within a superconducting solenoid, the cryostat and yoke for which together serve as the pressure vessel. While various options for the specific configuration of ND-GAr are being explored, essential design work for the detector has moved forward in recent months. This document describes basic mechanical, electrostatic, and gas flow design features of the ND-GAr TPC and presents results of electrostatic simulations of the interior of the pressure vessel for both single and dual-anode arrangements. Simulations are implemented with the Elmer finite-element software suite and related programs. [ABSTRACT FROM AUTHOR]

Copyright of Hydrometallurgy of China is the property of Hydrometallurgy of China 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.)

The direct buried steam pipeline with effective insulation has great potential application in the district heating systems. In this study, a life cycle cost model for the direct buried steam pipeline was established, and an optimization method was proposed to improve the insulation performance. The influences of insulation material and pipe diameter on the total life cycle cost, economic thickness, energy efficiency, and payback period were analyzed. Under the low-temperature working conditions, the composite insulation scheme composed of high-temperature resistant glass wool (HTRGW) and SiO2 aerogel blanket (SAB) exhibited excellent economic efficiency. Moreover, the life cycle cost and economic thickness show a significant decrease with the increase of pipe diameter, and the economic benefit increased appropriately. When the pipe diameter increased from DN100 to DN700, the life cycle cost was decreased by 351 RMB/m, the economic thickness was decreased by 71 mm, and the economic benefit was increased by 30 RMB/m. Under the high-temperature working conditions, aluminium silicate wool (ASW) was involved in the insulation scheme. When the HTRGW/SAB was adopted instead of HTRGW/ASW, the total life cycle cost was reduced by 133–224 RMB/m, the economic thickness was reduced by 52–55 mm, and the economic efficiency was increased by 17–22 RMB/(m·a).

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University 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.)

As a new Non-destructive Evaluation (NDE) technique, capacitive imaging (CI) has been used to detect defects in oil pipelines, composite sucker rods and storage tanks in recent years. When a CI sensor is used to detect corrosion defect on a conducting surface with or without an insulation layer, the depth information of corrosion defect is difficult to acquire due to the non-linearity of the probing field. This paper proposed a corrosion depth inversion method based on the lift-off effect of the CI technique. The proposed depth inversion method, which includes three steps, namely establishing the lift-off curve, obtaining the scan curve and fitting inversion, are introduced and evaluated. In the FE simulations, the error rates of the inversion depths are less than 1.20%. CI experiments were carried out to acquire the depth information of a step shape specimen using the CI experimental system and the proposed corrosion depth inversion method. The results show that the depth inversion method can meet the need of obtaining the actual depth information with the error rates of the inversion depths being less than 10.00%. A CI experiment on a machined and corroded specimen was carried out to further demonstrate the feasibility of the proposed inversion method for corrosion defects with different depths. Both results from FE models and experiments indicate that the proposed method is promising to achieve the quantitative NDE of the Corrosion Under Insulation (CUI).

Celiac patients are required to strictly adhere to a gluten-free diet because even trace amounts of gluten can damage their small intestine and leading to serious complications. Despite increased awareness, gluten can still be present in products due to cross-contamination or hidden ingredients, making regular monitoring essential. With the goal of guaranteeing food safety for consuming labeled gluten-free products, a capacitive aptasensor was constructed to target gliadin, the main allergic gluten protein for celiac disease. The success of capacitive aptasensing was primarily realized by coating a Parylene double-layer (1000 nm Parylene C at the bottom with 400 nm Parylene AM on top) on the electrode surface to ensure both high insulation quality and abundant reactive amino functionalities. Under the optimal concentration of aptamer (5 μM) used for immobilization, a strong linear relationship exists between the amount of gliadin (0.01-1.0 mg/mL) and the corresponding Δ C response (total capacitance decrease during a 20 min monitoring period after sample introduction), with an R 2 of 0.9843. The detection limit is 0.007 mg/mL (S/ N > 5), equivalent to 0.014 mg/mL (14 ppm) of gluten content. Spike recovery tests identified this system is free from interferences in corn and cassava flour matrices. The analytical results of 24 commercial wheat flour samples correlated well with a gliadin ELISA assay ( R 2 = 0.9754). The proposed label-free and reagentless capacitive aptasensor offers advantages of simplicity, cost-effectiveness, ease of production, and speediness, making it a promising tool for verifying products labeled as gluten-free (gluten content <20 ppm).

In this work, numerical simulation and experimental research were carried out on ablation mechanism of the first pulse (I pulse) insulation layer in a double-pulse solid rocket motor (SRM). Firstly, based on the internal thermal environment of the typical double pulse SRM, the internal flow field in combustion chamber of the double-pulse SRM with soft type pulse separation device (PSD) under the second pulse (Ⅱ pulse) working condition was numerically simulated. The results showed that the main reason for the difference of ablation in I pulse insulation layer was the difference of gas phase velocity. Secondly, based on the simulation analysis results, the experimental system for ablation of insulation layer was developed, and the ablation performance experiments under two gas phase velocities were carried out. It was found that a brittle carbonized layer had been formed on the surface of the insulation layer after the completion of I pulse work. In addition, at the beginning of Ⅱ pulse work, the suddenly generated gas flow made a denudation effect on the carbonized layer, which consumed a part of the carbonized layer. After the carbonized layer was peeled off, the gas flow continued to ablate the matrix of the insulation layer. Finally, the simulation analysis of the ablation process of the insulation layer under two gas phase velocities was carried out. The results showed that the velocity of the fuel gas is the main factor affecting the ablation rate of the insulation layer, which was consistent with the experimental results. It is proven that the model can be used to estimate the ablation amount of insulation of solid rocket motor. The conclusion can provide a significant reference for the internal heat protection design of the double-pulse SRM.

Lateral resistance of shear walls constructed with wood-based sheathing panels and lumber framing is largely governed by the strength of the sheathing-to-framing nailed joints. In new wall designs, a layer of soft thermal insulation is added between the sheathing and framing to increase the wall thermal resistance. Studying the influence of the intermediate insulation on the lateral load resistance of the nailed joint is essential for understanding the structural behavior of this kind of shear walls. An experimental study was conducted to measure the lateral resistance of the nailed joints. The results show that the insulation has a significant impact on the lateral resistance. An analytical model for predicting the lateral resistance, with embedment strengths of sheathing and framing members and nail bending strength as input parameters, was developed. The model predictions were compared with those from existing analytical models and with the experimental data. The ultimate lateral resistance of the nailed joints can be predicted with sufficient accuracy using the developed analytical model for the joints with up to 51-mm-thick intermediate insulation layers. [ABSTRACT FROM AUTHOR]

Water is an inorganic, non-flammable and easily available phase change material (PCM), which can be utilized for cold thermal energy storage (TES) application (melting point at 0°C). Although water has a specific heat of about 4.18 J g–1 K–1 and has melting enthalpy of about 333 J g–1, its application as an insulation layer was constrained. Phase separation (bulk convective movement during phase change, between ice and water), leakage from the container, supercooling during freezing, volumetric expansion and corrosion to the container were the main concerns for water as an insulation layer in TES systems. In this study, a thick non-flowing hydrogel (shape-stabilized PCM) was prepared by adding a small amount of inorganic additive material called LAPONITE® in water. The idea is to propose this thick non-flowing hydrogel as an insulating layer for cold TES application. The effect of this additive on viscosity and thermal properties of the water was studied. The phase change phenomenon of this hydrogel (between –10 and 20°C) was compared with water and the results are discussed. [ABSTRACT FROM AUTHOR]

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection 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.)

Electrophoretic deposition (EPD) is a material processing technology which uses direct current (DC) voltage to deposit thin layers on a metallic substrate. EPD is a promising coating technology for medical devices due to its advantages such as thin homogenous layers and a broad range of usable substrates. The objective of this paper is to demonstrate how EPD can be deployed successfully to apply an insulation layer on a stimulation electrode. The Mapping suction probe by inomed Medizintechnik GmbH, Germany, was coated in this investigation. The unique feature of this product is that it combines both a surgical vacuum and a stimulation probe and is used for brain tumour resection. As for the insulation layer, ethylene chlorotrifluoroethylene (ECTFE) was chosen because of its good dielectric and biocompatible properties. ECTFE particles (Halar®6514, Solvay Specialty Polymer, Italy) were mixed with a solvent (Novec™ 7100DL Engineered Fluid, 3M™) to form a suspension. The coating process was partly automatized to ensure good repeatability and reproducibility. For coating, the stimulation probe was immersed in the suspension so that the counter electrode, a stainless-steel net, surrounded it equidistantly. A heat treatment of the coated device in an oven (FED56, Binder, Germany) was required afterwards to melt the deposited polymer particles. After the heat treatment, a glossy black layer (layer thickness 42 μm) was observed on the substrate. A smooth and homogenous surface confirmed that the coating is suitable for surgical application. However, due to a high evaporation rate of the solvent, the ratio of particles and solvent changes and the coating process will have to be controlled in the future to achieve a stable process. Further advantages of EPD such as short processing time, straightforward process flow and scalability enables high production quantities which is attractive for industrial application. EPD might be a promising coating technology for medical devices in the future.

Inter‐turn short‐circuit fault of the stator winding is one of the most common faults of asynchronous generators and often found in doubly‐fed wind turbines. The improper treatment methods will lead to unnecessary power loss or further damage to the insulation layer. To solve this problem, an optimal power dispatch strategy (OPDS) is proposed which combines the control at the turbine level and the optimisation at the farm level. At the turbine level, the faulty turbine is down‐regulated based on the principle that the fault current does not exceed the rated current. At the farm level, particle swarm optimisation is used to optimise the power references considering wake effects to compensate for the power loss caused by the downregulated turbine. The effectiveness of OPDS is illustrated by comparing with two usually used strategies, one takes proportional dispatch strategy (PDS) and directly shuts down the faulty turbine, the other takes PDS but ignores the fault. The results show that OPDS can minimise power loss under the premise of protecting the faulty turbine. The study contributes to reduce the maintenance costs of wind farms and improve the operational capability of the wind turbine under fault conditions. [ABSTRACT FROM AUTHOR]

The encapsulation and insulation layers, which are typically located between a data electrode and a pixel electrode, should have low parasitic capacitance and enough electrical insulation to minimize signal distortion and crosstalk. Low dielectric constant (Dk) material reduces the parasitic capacitance and improve the insulation performance. New OLED flexible displays need organic‐based passivation and insulation materials for flexibility, light weight and productivity. Epoxy and acryl‐based materials were widely used in display industry for this purpose, but both have relatively higher Dk greater than 3.0, which limits to design new flexible displays and touch screen panels. DOW has invented a low Dk optical material based on silicone technology. A Dk value of 2.5 was achieved with a low viscosity of 12–18 mPa.s at 25°C for jetting without solvent. The newly developed product can be cured at 1,000 mJ/cm2 energy density at 395 nm with a light emitting diode (LED) ultraviolet (UV) lamp. One of the target applications is a dielectric layer for touch screen panels on organic light emitting diode (OLED) displays, but it is not limited to this. This material enables display manufacturers to develop and design ultrathin and innovative touch screen panels; and the novel and patented technology can be applied to various applications that require low dielectric constant. [ABSTRACT FROM AUTHOR]

The temperature difference between the exposed surface of an underground silo and the surrounding soil surface is significant, which means a silo can be easily found by infrared detection. We designed an infrared camouflage cloak consisting of an imitative layer and an insulation layer for the silos. The imitative layer is used to imitate the thermal response of the soil to the surrounding environment. The insulation layer is used to weaken the impact of the internal temperature field of the silo on the lower boundary of the imitative layer. A silo model including surrounding soil and a soil model without silo were established, and the influences of the material and thickness of each layer on the infrared camouflage effect were analyzed. The results show that when using a silicone rubber containing alumina powder with a volume fraction of 3.18% as the imitative material, its thermal inertia is in consistent with that of the soil. Meanwhile, it was found that the thickness of the imitative layer doesn't need to be greater than its thermal penetration depth to achieve the infrared camouflage, and the absence of the insulation layer will cause hot spots on the silo surface in winter to weaken the camouflage effect. The optimized thicknesses of the imitative layer and the insulation layer are 22 cm and 4 cm respectively. The simulations indicate that with the application of the cloak, the maximum value of the absolute values of the temperature differences between the average temperatures of the silo surface and the surrounding soil surface temperatures drops from 1.59 °C to 0.31 °C in summer and from 1.92 °C to 0.21 °C in winter. This designed cloak can achieve an all-weather and full-time passive infrared camouflage. [ABSTRACT FROM AUTHOR]

The target strata of sandstone-type uranium deposits are usually located in the fragile and loose strata, which makes it difficult to obtain core samples; consequently, a novel ice coring device for loose sandstone-type uranium deposits is proposed to solve this problem. Experiments proved that the artificial sample can replace the natural sample, and the coring method has high reliability. Ensuring the allegro formation of an ice valve with a given cold source is critical for this coring system, and reducing the loss of cold energy with help of insulation layer is one of the methods to speed up the formation of ice valve. Since the diameter of the drill tool is limited by its working scenario, the thickness of insulation layer is limited to ensure the size of core. Therefore, this paper conducted laboratory experiments of the insulation layer with different thicknesses to study the effect of the insulation layer on the formation of the sand–ice valve. Results show that the insulation layer can reduce the loss of cold energy during the freezing process and significantly affect the formation time of the sand–ice valve. When the thickness of the aerogel insulation layer is 2 mm, the freezing time is 44% shorter than that without insulation layer. According to the tests, the novel ice coring device is expected to solve the coring problem in loose sandstone-type uranium deposits.

As an indispensable part of high-voltage direct current (HVDC) cable, the semiconductive shielding layer plays the role of uniforming electric field in the cable. However, cable shielding materials >35 kV mainly rely on foreign imports in China, which belongs to the technical weak issues in the field of electrical materials. At present, there are few systematic reports on semiconductive shielding material of HVDC cable. In the work, the mechanisms of charge conduction and thermal conduction of semiconductive material have been introduced. Effect of raw material, carbon black content and the second conductive filler on the resistance characteristics of the semiconductive layer, the charge accumulation characteristics of the insulating layer and the interface characteristics have been studied. A kind of semiconductive layer as a high voltage terminal charge emission method has been proposed to study charge emission from the semiconducting layer to the insulation layer. This work can provide theoretical guidance for the research of semiconductive shielding materials.

Polymer-based composites with ceramic fillers could combine the advantages of both, which can be potentially used in electrical and electronic technology. In this work, the barium titanate (BaTiO(3)) nanofibres and the core–shell structured BaTiO(3)@Al(2)O(3) nanofibres with Al(2)O(3) insulation layer coated on the BaTiO(3) surface were both prepared via the electrospinning method. The appropriate incorporation of the ceramic nanofibres effectively improves the dielectric properties and energy density of the polymer. Moreover, the poly(vinylidene fluoride-co-hexafluoropropylene)-based composite films with the three-layer sandwich structure were fabricated to further promote the dielectric properties. The results show that the outer two layers with a higher content of BaTiO(3) nanofibres can make more contribution to the improved permittivity of the composites. In addition, the introduction of the interlayer with low loading of BaTiO(3)@Al(2)O(3) nanofibres promotes the breakdown strength. This work gives rise to the potential in high energy storage applications.

A compact system for detecting charge accumulation in the insulation layer of power electronic devices such as insulated gate bipolar transistor (IGBT) modules was developed. The amount of electric charge accumulated in IGBT modules at high dc voltages (100 to 5000 V) and in a wide temperature range (20 to 180 ℃) was measured using the system consisting of two units. The battery-operated sensing and transmission unit (500 × 700 × 300 mm³) was connected in series to an IGBT module to which various dc voltages were applied at various temperatures. The collected data were transmitted to a data receiving unit for analysis, which is electrically isolated from the sensing and transmission unit. The data received as a function of time Q(t) were analyzed to obtain various parameter values that provide information on the insulation status of the IGBT module, such as the amount of initial charge, absorption current, and conduction current under various conditions. On the basis of the ratio Q(t)/Q0, where Q0 is the amount of initial charge, the amount of charge accumulated in the IGBT modules under high-stress conditions was obtained. The compact system for accumulated charge detection will be convenient for evaluating the insulation characteristics of IGBT modules, which operate under harsh conditions in real power electronic devices such as those used in electric vehicles. [ABSTRACT FROM AUTHOR]

• Experimental investigation of inclined screws in mass timber panel concrete composite with insulation. • 30° angled screw shows higher stiffness and strength than 45° angled screw in cross-pair. • Screws with larger embedment length shows higher stiffness and strength. • Insulation layers significantly reduce the stiffness and strength of the connection. • Stiffness of the connection is more sensitive to insulation layer than strength. The Mass Timber Panel-Concrete (MTPC) composite floor systems are often encountered in mass timber buildings. Such a floor system consists of a Mass Timber Panel (MTP) connected to a reinforced concrete slab with Self-Tapping Screw (STS) connector and a sound insulation layer in between. In this study three types of MTPs with normal weight concrete, three insulation thicknesses, two screw embedment lengths and two screw angles were tested to characterize connection stiffness and strength. The main goal of this connection test program was to provide preliminary test data to assist in the development of an analytical model to predict connection lateral stiffness and strength considering the insulation layer in the MTPC system. Test results showed that connections with screws at an insertion angle of 30° had a larger stiffness and strength than connections with screws inserted at a 45° angle. Stiffness appears to be more sensitive to the presence of an insulation layer compared to strength. Overall, 35–50% and 55–65% reduction of serviceability stiffness, and 5–15% and 22–34% reduction of strength were noticed for an insulation thickness of 5 mm and 15 mm, respectively. Screws in Cross Laminated Timber (CLT) showed higher strength while screws in Glue Laminated Timber (GLT) showed higher stiffness, but the difference is insignificant in all three MTP products with different failure modes. [ABSTRACT FROM AUTHOR]

A well-known strategy for minimizing the negative effects of prolonged low temperatures on frost-susceptible subgrade is using insulation layers. Insulation layers help to mitigate the formation of ice lenses and frost heave in the subgrade. This paper evaluates the effect of using bottom ash (B.Ash), as well as polystyrene boards, on the seasonal response of the pavement at the University of Alberta's Integrated Road Research Facility (IRRF) in Edmonton, Canada. Over the course of one year of data monitoring, from July 2014 until July 2015, different seasons (non-freeze-thaw, frozen, and recovering) were distinguished using the temperature and moisture data received from time domain reflectometers (TDRs) and thermistors installed across the pavement depth. Then, the time history data collected from falling-weight deflectometer (FWD) tests was used to identify the characteristic response of different sections. Results revealed that the B.Ash section performed similarly to the control section (CS) in terms of viscoelastic behavior, and the B.Ash perfor med considerably better than the CS in terms of the risk of fatigue cracking. However, the polystyrene sections were more prone to damages during the summer when the hot mix asphalt (HMA) temperature was more than 25°C. [ABSTRACT FROM AUTHOR]

Temperature is an important factor in designing and maintaining tunnels, especially in cold regions. We present three-dimensional numerical simulations of tunnel temperature fields at different temperature conditions. We study the tunnel temperature field in two different conditions with relatively low and high ambient temperatures representing winter and summer of northeast China. We specifically study how these temperature conditions affect tunnel temperature and its migration to surrounding rocks. We show how placing an insulation layer could affect the temperature distribution within and around tunnels. Our results show that the temperature field without using an insulation layer is closer to the air temperature in the tunnel, and that the insulation layer has shielding effects and could plays an important role in preventing temperature migration to surrounding rocks. We further analyzed how thermal conductivity and thickness of insulation layer control the temperature distribution. The thermal conductivity and thickness of insulation layer only affect the temperature of the surrounding rocks which are located at distances below ~20 m from the lining. [ABSTRACT FROM AUTHOR]

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For spherical layer of insulation surface, we give a solution of the linear time-dependent heat transfer problem with axially symmetric distribution of the heat flux density over the layer exterior surface. The insulation material has anisotropic heat conduction properties characterized by the ratio of the thermal conductivities along and across the layer. The solution obtained is used for qualitative estimate of the effect of this ratio on the leveling of temperature distributions for non-uniform heating specific for conditions of an axially symmetric hypersonic flow past a hemispherical blunting. [ABSTRACT FROM AUTHOR]

• Building a defect detection system of aircraft cable insulation layer. • Using ultrasonic guided waves to detect multiple defects simultaneously. • Using deep forest method to identify defect categories. Due to the special internal environment of aircraft, cable damage is inevitable, which usually starts from insulation layer defects and may cause major economic losses, and even seriously threaten the life of people on board. According to the above issue, a defect detection system for aircraft cable insulation layer based on ultrasonic guided waves (UGWs) is built in this paper. In order to ensure the complete coupling between the sensor and the insulation layer of the aircraft cable, the macro fiber composite (MFC) flexible sensor is employed in the system. Both simulation and experimental results show that this method can simultaneously monitor four different types (abrasion, cut, semi-stripping and full-stripping) of cable insulation layer defects at different locations on the same cable. The reflection signals of different types of defects are extremely similar and difficult to distinguish directly. In this paper, a classification method for four types of defects based on the deep forest method is proposed. This method requires a small sample size, and the classification performance is not affected by network structure and parameters. The recognition accuracy can reach 100%, avoiding the problem of traditional deep learning classification relying on a large number of samples and requiring parameter adjustment. The proposed method in this paper is proven to be able to effectively carry out online monitoring and accurately classify defect types, which has guiding significance for aircraft maintenance personnel to take corresponding measures in time. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel superhydrophobic polymer concrete coating is firstly developed. • Adhesive strength between coating and insulation layer is largely improved by 96%. • The coating exhibits excellent robustness and anti-icing resistance. • The coating is expected to have better performance in insulation layer protection. Porous and hydrophilic concrete coating on the insulation layers of dam suffered from adhesion of cold water and subsequent icing in a freezing environment, which might result in severe ice pullout phenomenon. Although a lot of superhydrophobic concrete (SC) coatings have been developed, the coatings generally had poor adhesive strength with the insulation layers, which restricted their application in protecting the insulation layers. Herein, we first developed a novel superhydrophobic polymer concrete (SPC) coating by polyacrylate emulsion (PAE) and stone protector addition, and nylon mesh cover. The SPC coating exhibited good superhydrophobicity with a contact angle of ∼156° and a sliding angle of ∼10°. And the adhesive strength between SPC coating and insulation layer was 96 % larger than that of SC coating, indicating much better performance in the insulation layer protection. In addition, the SPC coating possessed excellent surface robustness, anti-icing capacity, and self-cleaning property, and was expected to be a promising candidate for protecting the insulation layers. [ABSTRACT FROM AUTHOR]

Efficient thermal insulation materials considerably lower power consumption for heating and cooling of buildings, which in turn minimises CO 2 emissions and improves indoor comfort conditions. However, the selection of suitable insulation materials is governed by several factors, such as the environmental impact, health impact, cost and durability. Additionally, the disposal of used insulation materials is a major factor that affects the selection of materials because some materials could be very toxic for humans and the environment, such as asbestos-containing materials. Therefore, there is a continuous research effort, in both industry and academia, to develop sustainable and affordable insulation materials. In this context, this work aims at utilising the packing industry wastes (cardboard) to develop an eco-friendly insulation layer, which is a biodegradable material that can be disposed of safely after use. Experimentally, wasted cardboard was collected, cleaned, and soaked in water for 24 h. Then, the wet cardboard was minced and converted into past papers, then cast in square moulds and left in a ventilated oven at 75 °C to dry before de-moulding them. The produced layers were subjected to a wide range of tests, including thermal conductivity, acoustic insulation, infrared imaging and bending resistance. The obtained results showed the developed material has a good thermal and acoustic insulation performance. Thermally, the developed material had the lowest thermal conductivity (λ) (0.039 W/m.K) compared to the studied traditional materials. Additionally, it successfully decreased the noise level from 80 to about 58 dB, which was better than the efficiency of the commercial polyisocyanurate layer. However, the bending strength of the developed material was a major drawback because the material did not resist more than 0.6 MPa compared to 2.0 MPa for the commercial polyisocyanurate and 70.0 MPa for the wood boards. Therefore, it is recommended to investigate the possibility of strengthening the new material by adding fibres or cementitious materials., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 Published by Elsevier Ltd.)