Low Loss Research Articles

Influence of silane and polyethylene glycol functionalization of boron nitride nanosheets on mechanical and thermal properties of epoxy nanocomposites: Machine and deep learning forecasting

AbstractThe influence of hexagonal boron nitride (hBN) nanosheet surface modification on epoxy nanocomposites' mechanical and thermal properties were investigated. An innovative approach was developed for synthesizing hBN nanosheets (hBNNs) via optimized ultrasonic‐assisted liquid‐phase exfoliation (UALPE), followed by functionalization with 3‐aminopropyltriethoxysilane (APTS) and polyethylene glycol (PEG600) for nanocomposite preparation. Compared to unmodified epoxy, nanocomposites containing 0.3 wt% of pristine hBNNs exhibited significant enhancements in flexural strength (125.28 MPa) and tensile strength (53.35 MPa), with respective increases of 40.57% and 43.23%. PEG‐hBNNs improved flexural and tensile strengths to 136.83 and 58.57 MPa, respectively. The most substantial enhancements were observed with APTS‐hBNNs, yielding flexural and tensile strengths of 174.13 and 63.53 MPa, reflecting increases of 95.37% and 70.50%, attributed to better interfacial interactions and a more effective crack deflection mechanism. Thermal stability analyses revealed superior performance of modified hBNNs epoxy nanocomposites, increasing 8.2°C and 6.3°C at 50 wt% degradation as compared to the unmodified system, owing to enhanced physical barrier properties. Structural and morphological analyses validated the successful exfoliation and modification of hBNNs. Predictive models utilizing machine and deep learning (DL) techniques, particularly DL with the adaptive moment estimation (ADAM) optimizer, effectively forecasted mechanical properties, achieving high R2 values.HIGHLIGHTS 0.3 wt% modified hBNNs epoxy nanocomposite showed the highest mechanical strength Improved thermal stability of epoxy nanocomposite by modification of hBNNs Improved crack deflection mechanism in the presence of surface‐modified hBNNs Deep learning with ADAM optimizer showed high R2 and low prediction loss

Comparative analysis of operative time, blood loss, and X-ray parameters: Two-dimensional navigation guided percutaneous endoscopic transforaminal discectomy vs. conventional microscopic surgery for lumbar disc herniation

PurposeThis retrospective comparative study aims to evaluate the clinical efficacy of two-dimensional (2D) navigation-guided percutaneous endoscopic transforaminal discectomy in comparison to conventional microscopic surgery for the treatment of lumbar disc herniation (LDH), based on operative time, blood loss, and X-ray examination parameters. MethodsClinical data of patients who underwent either 2D navigation-assisted endoscopic (2D-NAE) discectomy or conventional microscopic surgery for LDH were retrospectively reviewed. Baseline characteristics, perioperative data, clinical outcomes (including visual analog scale [VAS] scores, Oswestry Disability Index [ODI] scores, and Modified MacNab criteria), and complications were compared between the two groups. ResultsA total of 95 patients were included, with 80 having complete follow-up data. The 2D navigation group comprised 47 patients, while the conventional microscopic surgery group had 33 patients. Both groups showed significant improvement in VAS and ODI scores at each follow-up time point (P < 0.05). The perioperative analysis favored the 2D navigation-assisted group, with a significantly shorter operative time (42.77 ± 7.56 vs. 59.33 ± 3.30 min; p < 0.01) and lower blood loss (10.34 ± 2.24 vs. 11.55 ± 2.20 ml; p = 0.02). The number of X-ray examinations required was similar between the two groups (2.34 ± 0.48 vs. 2.39 ± 0.56; p = 0.65), and post-operative hospitalization durations were comparable (p = 0.5). Clinical efficacy, as reflected by VAS scores for legs and ODI scores, showed no significant differences between the groups. Additionally, the Modified MacNab criteria indicated similar rates of excellent and good outcomes. ConclusionBoth 2D-NAE discectomy and conventional microscopic surgery demonstrated comparable therapeutic outcomes for LDH, with favorable clinical efficacy and safety profiles. However, 2D-NAE surgery may offer additional benefits, including shorter operative times, reduced blood loss, and fewer X-ray examinations.

Innovation and possibility of various coating materials with microwave hybrid heating

Cavitation wear is causing considerable financial losses for a range of industries, such as chemical, food processing and hydropower plants. Microwave cladding process involves the application of a coating of another material over the surface of a specific material, which offers properties beneficial for high electrical conductivity, low loss tangent and excellent thermal stability. This review article is intended to provide a basic understanding of the properties of various types of microwave cladding materials. This chapter also emphasises on the characterisation of the samples produced through the microwave cladding on various substrate materials. Furthermore, this chapter describes the potential applications of the microwave cladding process in numerous engineering and industrial sectors. Additionally, this chapter also reports the potential future technological advancements in the field of microwave cladding process.

Design of a high-gain, low-ECC 2x2 MIMO antenna for 28 GHz 5G wireless communication system

In this paper, a 2 × 2 MIMO antenna with inset feed is designed for the frequency Range 2 (FR2) millimeter wave frequencies such as n257 (26-29.5 GHz), n258 (24.25-27.5 GHz), and n261 (27.5-28.35 GHz). The MIMO antenna is designed and fabricated using low loss Rogers RT/duroid 5880 substrate having dimension of 1.4λ 0×2.8λ 0×0.073λ 0, where λ 0 is the free-space wavelength operating at 28 GHz.The defected ground structure (DGS) minimized the surface waves current. Thus DGS are used to increased the gain and the isolation of the proposed MIMO antenna design. The gain of the MIMO antenna reported is 10.3 dBi with 97.01% radiation efficiency at 28 GHz resonant frequency. The -10 dB impedance bandwidth lies between 26.95-29.50 GHz, which covers the 5G frequency bands. The isolation is ≥28 dB and envelope correlation coefficient (ECC) is 10 −5, respectively, in the complete operating band.

Dual‐Phase Enabled Sinusoidal Current Anodizing for Efficient Preparation of High Specific Capacitance Anode Aluminum Foils

The anodized aluminum oxide prepared by anodizing is the core of aluminum electrolytic capacitors, and its quality determines the performance of aluminum electrolytic capacitors. The traditional direct current (t‐DC) anodizing method commonly used in industrial production today with low current density has the problems of low anodizing efficiency, poor crystallinity, and high formation constants of the oxide film. However, high current density direct current anodizing has the problems of severe defects of the oxide film and much thermal dissolution of aluminum foil. Herein, the dual‐phase enabled sinusoidal current (DESC) anodizing method is proposed for the preparation of 200 V anodized aluminum foil with much higher efficiency and performance. After testing, it is found that the alumina prepared by the DESC method has higher crystallinity and fewer defects. Consequently, the specific capacitance of the DESC sample is 23% greater than that of the t‐DC anodized sample, while the former displays a lower loss angle tangent and leakage current. Meanwhile, DESC anodizing takes 60% time less than t‐DC anodizing due to its high current density. The DESC anodizing method has been identified as a promising avenue for further investigation, exhibiting high efficiency and performance.

ISOS-SAB DC/DC Converter for Large-Capacity Offshore Wind Turbine

This study offers a modular isolated grid-connected DC/DC medium-voltage DC aggregation converter to support offshore full DC wind farms’ need for lightweight and highly efficient power aggregation and transmission. The converter can simultaneously have a smaller transformer size and lower switching frequency during operation through the dual-voltage stabilization three-loop control strategy and phase-shift modulation strategy, which greatly reduces the space occupied by the converter and lowers the switching loss, Additionally, the use of a two-level structure at a lower switching frequency has lower loss, which effectively reduces the cost of the power device compared with the commonly used three-level converter. The input series output series connection between the converter sub-modules effectively lowers the voltage stress on each power switching device and facilitates expansion into a multi-module structure, expanding its application in high-voltage and large-capacity environments. This study analyzes the two working modes of the DC/DC converter and its control approach, in addition to providing a detailed introduction to the application scenarios of this converter. Ultimately, the efficacy and practicability of the suggested topology and control scheme are confirmed by simulations and experiments.

A reconfigurable transmitarray unit cell employing liquid metal

AbstractIn this paper, a reconfigurable transmitarray unit cell using liquid metal is presented. It consists of three conducting layers where the geometries of the resonators, on the different layers, differ and consist of an arrow shape together with rotated split rings. The arrow‐shaped conducting layer has the capability to convert the polarization of the incoming waves by 90°. The split ring resonators, on the upper and lower conducting layers, have the same dimensions but different orientations (horizontal and vertical polarization). Several fluidic channels are placed beneath/above the conducting layers. The transmission behaviour of the unit cell can be changed by altering the geometrical parameters which is achieved by injecting the liquid metal into the channels. More than 300° phase shift range with a maximum S21 of ∼ −1.5 dB at 3.3 GHz is obtained. It exhibits 3 dB of insertion loss over a bandwidth ranging from 3.2 to 3.43 GHz. It is the first time that a transmitarray unit cell, reconfigured employing liquid metal, provides a combination of low insertion loss and large phase shift range. The proposed prototype was fabricated and measured within an open‐ended waveguide and the measured results agree well with the simulations and verify the effectiveness of the design. The reconfigurable transmitarray unit cell can be used to design beam‐scanning arrays, as well as for applications in wireless communications.

Novel High Efficiency V‐Band Pure TEM D‐PRGW Antenna for 5G mmWave Applications

ABSTRACTThis paper starts with the proposal of an enhanced version of a planar rectangular slot antenna fed by the quasi‐TEM printed ridge gap waveguide (PRGW), attended with a numerical study of a miniaturization procedure showing the limitations of the conventional PRGW‐based antennas. Then innovative solution is introducing a new miniaturized pure TEM wide‐band slot antenna utilizing double PRGW (D‐PRGW) technology; the proposed approach is self‐packaged and shows high potential for enhancing antenna performance, particularly in terms of bandwidth, gain, and compactness. This technology is featured with low loss, high performance, and compact size; it consists of surrounding the ridge area with a double layer of electromagnetic band gap (EBG) lattice instead of one to eliminate the surface waves effectively and keep the signal completely confined inside the ridge area with strict minimum rows of EBG. Therefore, a broad impedance matching bandwidth (|S11| ≤ −10 dB) of 33.33% is obtained from 50 to 70 GHz, which covers the unlicensed NR parts (n262; amp; n263) of the V band. Furthermore, the antenna achieves a peak gain of approximately 16 at 65 GHz while the overall efficiency remains above 90% across the entire operating frequency band. The high performance along with the compact size of this novel design makes it a good candidate for 5G wireless communications applications centered around 60 GHz.

Plasmonic coupling effect of annealed gold nanoarrays

Periodic metal nanodisc arrays have the potential to exhibit regularly spaced large local field enhancements, especially when high-Q collective plasmonic grating resonances can be obtained. Here we demonstrate how Laser interference lithography (LIL) as a maskless and high throughput technique can be used to fabricate these on square centimeter areas. The drawback of LIL is the rather fixed ratio of the size of the individual nanostructure (d) to the period of the array (p) of about d/p ∼ 0.5 for the setup used in the current article, thereby, limiting its ability to create resonances with ultra-high quality factors (Q-factors). To improve the Q-factor of the resonances of the arrays, we study the effect of thermal annealing nanodisk arrays fabricated by LIL and a lift off process. The nanodisk arrays with periods of 400 nm and 500 nm exhibited a plasmonic resonance, which was caused by the interaction of the single disk resonance and a (1 0) grating resonance. Annealing for a short duration lowered the d/p ratio from 0.5 to 0.4, and led to smoothening of the disk surfaces and growth of gold grains, resulting in lower ohmic and radiative losses and doubling of the Q-factor of the resonances. Finite element method (FEM) simulations were used to monitor this improvement in material parameters. Annealing for a longer duration disintegrated the nanodisk into several smaller particles while maintaining the overall periodicity of the array. While the plasmonic resonances of the experimentally investigated fragmented disks were basically destroyed, simulation predict that for larger periods fragmented nanodisk arrays (keeping the d/p ∼ 0.4) can exhibit extremely strong and sharp resonances whose Q-factor increases more than 58.4 times compared to the unfragmented discs. In addition, simulations show a massive enhancement of the local electric field promising immense potential for surface enhanced Raman sensing.

The effect of house price constraint conditions in land granting on the second-hand housing market: evidence from Beijing, China

ABSTRACT To curb the surge in housing prices, Chinese governments have introduced various measures in the real estate market. House price constraint conditions (HPCCs) are conditions for sale in land granting which restrict the selling price of newly built houses. Such unique practice has been used as price regulation and signal in many cities with little understanding of its impact. This study aims to investigate the effectiveness, mechanism, and cost of HPCCs on the second-hand housing market for policy improvement, completing existing literature primarily focusing on housing policies. We collected data on land granting and second-hand house transactions in Beijing, which was the first to implement HPCCs. Employing difference-in-difference and other empirical techniques, we find that land granting with HPCCs alters buyers’ and sellers’ behaviours and expectations, leading to a significant decrease in the price level and growth rate. However, HPCCs are associated with lower supply, increased speculation, inequality issues, and potential loss of fiscal revenue. Policymakers need to improve HPCCs while considering market-oriented regulation tools.

Synthesis and optical properties of fluorinated polyurethaneimide electro-optic waveguide polymer

Fluorinated polyurethaneimide (PUI) electro-optic waveguide polymer with polyurethane and polyimide chain segment structures was synthesized by stepwise polymerization using the synthesized amino ester oligomer pu and imide oligomer pi as monomers. Since the main chain structure of the synthesized PUI had the functionality of both polyurethane and polyimide chain segment structures, it combines the excellent thermal and film-forming properties of polyurethanes and polyimides, as well as lower optical transmission loss in the near-infrared wavelength band. The glass transition temperature (Tg) of PUI was 182 °C, and the 5% heat loss decomposition temperature was 325 °C. The PUI had good optical properties with an optical propagation loss of 1.10 dB/cm and an electro-optic (EO) coefficient (γ33) of 86 pm/V at a wavelength of 1550 nm. A Mach-Zehnder interferometric polymer waveguide EO modulator had been designed and fabricated by using the PUI as a waveguide electro-optic core layer. The prepared polymer waveguide EO modulator showed a good electro-optic modulation response at a wavelength of 1550 nm under an applied 1 kHz sinusoidal modulation signal. The results showed that the synthesized PUI met the performance requirements for the preparation of polymer optical waveguide devices and was a polymer electro-optic waveguide material with good overall performance.

A Novel Upside-Down Thermal Annealing Method Toward High-Quality Active Layers Enables Organic Solar Cells with Efficiency Approaching 20.

The emerging non-fullerene acceptors with low voltage losses have pushed the power conversion efficiency of organic solar cells (OSCs) to ≈20% with auxiliary morphology optimization. Thermal annealing (TA), as the most widely adopted post-treatment method, has been playing an essential role in realizing the potential of various material systems. However, the procedure of TA, i.e., the way that TA is performed, is almost identical among thousands of OSC papers since ≈30 years ago other than changes in temperature and annealing time. Herein, a reverse thermal annealing (RTA) technique is developed, which can enhance the dielectric constant of active layer film, thereby producing a smaller Coulomb capture radius (14.93 nm), meanwhile, forming a moderate nano-scale phase aggregation and a more favorable face-on molecular stacking orientation. Thus, this method can reduce the decline in open circuit voltage of the conventional TA method by achieving decreased radiative (0.334 eV) and non-radiative (0.215 eV) recombination loss. The power conversion efficiency of the RTA PM6:L8-BO-X device increases to 19.91% (certified 19.42%) compared to the TA device (18.98%). It is shown that this method exhibits a superb universality in 4 other material systems, revealing its dramatic potential to be employed in a wide range of OSCs.

Optical properties of crystals and two-phase ceramics of the AgCl0.25Br0.75 – AgI system

Research of materials’ optical properties is critical for further development and manufacturing of optical products. While recently, single crystals and two-phase ceramics of the AgCl0.25Br0.75 – AgI system have been developed by the authors. This work is focused on studying the transmission ranges, refractive index dispersion, optical losses, and photoresistance of materials in the AgCl0.25Br0.75 – AgI system, as well as comparing the properties of single-crystals and ceramics. The materials are transparent in the visible and IR regions from 0.49 to 54 um, as well as in the terahertz (far IR and millimeter regions) of 300–1500 um (0.3–1.0 THz). For all compositions, the refractive index in the IR varied from 2.107 to 2.436. The materials’ absorption coefficients were (0.06–6.67) ∙ 10-4 in the middle IR, which is lower compared to other halide materials known and indicates low optical loss. Finally, both single-crystals and two-phase ceramics showed a trend towards an increase in photoresistance with a rise of the AgI content in the AgCl0.25Br0.75 solid solution. After UV irradiation, the materials showed a decrease in transmission in the visible and middle IR (to 10 µm) with negligible loss at a wavelength of 10 µm or more. For a single crystal and two samples of ceramics with a composition of 20 mol. % AgI in AgCl0.25Br0.75, a comparison of properties was conducted in this study. Based on the comparison results, close but not identical values of the refractive indices, an increase in the absorption coefficient for ceramic materials, and a low photoresistance of the sample obtained from the mechanical mixture were revealed. The last two characteristics are associated with the high heterogeneity of two-phase ceramics based on a mechanical mixture, which leads to a deterioration in functional properties. These results prove high prospects for the use of these materials in fiber optics and photonics for medical technologies, thermography, and optoelectronics.

Enhanced mechanical and dielectric properties of lignocellulosic composite papers with biomimetic multilayered structure and multiple hydrogen-bonding interactions

Lignocellulosic papers (LCP) are favored for electrical insulating applications due to their environmental friendliness, ease of processing, and cost-effectiveness. However, the loose structure and numerous pores inside LCP result in the poor mechanical and electrical insulating properties, posing challenges in meeting the requirements for the rapid upgrading of high-voltage electrical equipment. Herein, a 3D interconnective structure composed of 3D aramid nanofibers (ANF) and 2D carbonylated basalt nanosheets (CBSNs) is introduced to enhance the structure and the chemical bonding interactions of LCP. This is achieved by impregnating LCP into an ANF-CBSNs suspension, where the 3D interconnective ANF framework hosts numerous CBSNs. The resultant LCP/ANF-CBSNs (LCP/A-C) composite papers exhibit multilayered structure and multiple hydrogen-bonding interactions, demonstrating excellent mechanical and electrical insulating properties. Notably, the optimized LCP/A-C5 composite papers exhibit remarkable tensile strength (23.15 MPa) and dielectric breakdown strength (20.14 kV·mm−1), respectively, representing 229 % and 145 % increase compared to those of the control LCP. These impressive properties are integrated with excellent bending ability, outstanding high temperature resistance, exceptional volume resistivity, and low dielectric constant and loss, demonstrating their potential as highly promising electrical insulating papers for advanced high-power electrical equipment.

Surface hydrophobicity mechanism of poultry red mite, Dermanyssus gallinae (Acari: Dermanyssidae), gives novel meaning to chemical control

Surface hydrophobicity of organisms provides biological self-protection. The hydrophobicity of pest surface, acting as a main obstacle for the pest control, can lead to low utilization and high loss of pesticides. Dermanyssus gallinae is a notorious pest in egg-laying hens, whose control primarily depends on acaricide spraying, while its surface hydrophobicity and potential influence on pesticide effectiveness are not clear. In the present study, the contact angle measurements revealed that the surface of D. gallinae was hydrophobic. Analysis using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that the surface microstructures of D. gallinae consist of cuticular folds, with a lipid-rich outermost layer of the cuticle. Based on gas chromatography-mass spectrometry (GC-MS) and gas chromatography (GC), it was found that the major compositions of cuticular lipids were fatty acids and n-alkanes. Modifying the chemical compositions and microstructures of the D. gallinae surface resulted in a reduction in surface hydrophobicity and an increase in the permeation of Rhodamine B through the cuticle. This observation suggested that the chemical compositions and microstructures were pivotal in determining surface hydrophobicity, hindering compound penetration into the cuticle. Finally, it was found improving the wettability of pesticide solution by adding surfactants could overcome the surface hydrophobicity and enhance the efficacy of pesticide against the mites. This study sheds light on the surface hydrophobicity mechanism of D. gallinae and provides a novel strategy to improve the efficacy of acaricides against the mites.

Hydrophilic-Hydrophobic Network Hydrogels Achieving Optimal Strength and Hysteresis Balance.

The biocompatibility and adaptability of hydrogels make them ideal candidates for use as artificial tendons and muscles in clinical applications, where both muscle-like strength and low hysteresis are essential. However, achieving a balance between a high strength and low hysteresis in hydrogels remains a significant challenge. Herein, we demonstrated a self-assembly process of heterogeneous hydrogels to meet the dilemma. And the hydrogels are composed of both hydrophilic and hydrophobic polymers. The hydrophilic network absorbs water, causing phase separation into a water-rich phase and a water-poor phase, while hydrophobic polymers and entanglement of the network arrest phase separation. Our results demonstrated that these hydrogels achieve remarkable mechanical properties, with a strength of 848.8 kPa, a low energy loss of 19.6 kJ/m3, and minimal hysteresis (0.046) during loading-unloading cycles. The reinforcing mechanisms underlying these properties are attributed to crystallization, molecular entanglement, and chain rearrangement induced by stretching. Furthermore, the combination of hydrophilic and hydrophobic networks is exceedingly rare in reported hydrogels.

Ultra-compact silicon nitride dual-polarization mode converter for visible light demonstrated on a thinned 320 nm silicon wafer

A dual-polarization higher-order mode converter is proposed for visible light, which operates within the (400–700) nm range, to enhance data capacity in on-chip visible light communication systems. The proposed structure is optimized at wavelengths of 410 nm, 560 nm, and 660 nm to cover the entire visible spectrum. These three optimized designs, in particular, have an intrinsic property wherein they can be optimized to simultaneously convert both polarized fundamental (TE0) and fundamental (TM0) modes to the second higher-order (TE2) and (TM2) modes, providing significant advantages for hybrid multiplexing systems like PDM-MDM and PDM-WDM schemes. The mode converters are constructed on a silicon nitride waveguide. This waveguide is etched and filled with silicon dioxide material to create two dielectric substrips, followed by an additional rectangle shape etched using the same process into the propagating waveguide. This alteration enhances insertion loss and diminishes crosstalk to the fundamental mode. The devices achieve a broad operating bandwidth of approximately 100 nm while maintaining a compact footprint of only 1µm×1.754µm for the entire device at the center wavelength of 560 nm. Upon optimizing the suggested structure, a TE0-to-TE2 mode converter with a modal conversion efficiency of 94% is designed at the wavelength of 410 nm. The insertion loss is 0.6025 dB, and the crosstalk with the transverse electric fundamental mode TE0 is 35 dB. The reported devices feature a straightforward structure with low insertion loss and minimal crosstalk.

The Negative Pressure Wound Therapy for Flap Salvage

Negative Pressure Wound Therapy (NPWT) effectively manages complex wounds by promoting fluid drainage, stabilizing the wound environment, and reducing bacterial load. It aids in granulation tissue formation and modulation of inflammatory reactions. NPWT is increasingly used in reconstructive surgery, particularly in flap procedures, enhancing wound healing and cosmetic outcomes while reducing flap complications. Despite concerns about flap compromise, clinical trials demonstrate low flap loss rates with NPWT. Strategies like observation windows and implantable Doppler devices help overcome monitoring challenges. However, conclusive evidence regarding NPWT's safety and impact on flap vascularity is limited due to scarce studies. The study involved 40 healthy adult patients, mostly male, with soft tissue defects primarily caused by road traffic accidents. They were split into two groups: NPWT (25 patients) and conventional dressing (15 patients). The NPWT group was further categorized into high pressure (8 patients) and low pressure (17 patients) subgroups. Results showed lower flap edema in NPWT groups compared to controls, but high pressure NPWT led to higher flap ischemia and infection rates. Overall, low pressure NPWT yielded the best clinical and aesthetic outcomes with fewer complications. The study suggests a delayed NPWT approach and low-pressure settings for optimal vascular perfusion in Fasciocutaneous flaps, emphasizing the need for further trials to establish its efficacy and determine ideal pressure settings for different flap types.

Constructing house-of-cards-like networks with BNNS confined in interlocking Al2O3 platelet skeletons for thermally conductive epoxy composites

The construction of 3D filler networks is an effective strategy to improve the thermal conductivity of epoxy resins, yet it is still severely limited by the disconnection of conduction channels. In this contribution, an original interlocking hybrid skeleton with continuous conduction channels was developed by assembling BNNS into an in situ-formed interlocking Al2O3 platelet skeleton using commercial polyurethane as a template, where large intergranular contact areas of Al2O3 platelets were established by sintering to greatly decrease the contact thermal resistance. Besides, the interlocking Al2O3 skeleton coupled with BNNS under hydrogen bonding endowed further improvement of its thermal conductivity. The optimized Al2O3/BNNS/EP composite displayed an excellent thermal conductivity of 5.01 W/mK at 15.3 vol% of Al2O3 and 11.4 vol% of BNNS loading, far higher than that of neat epoxy resin by 1904.0 %. Meanwhile, the interlocking hybrid skeleton provided the epoxy resin with low dielectric loss, satisfactory thermal stability and flame retardancy.

Association of SO2-Generating Pads before Packaging and during Cold Storage to Extend the Conservation of 'Italia' Table Grapes.

The SO2-generating pads contain different concentrations of sodium metabisulfite, which absorbs water from the grapes' transpiration, releasing SO2 gas, and there are slow-(SlowSO2) and dual (DualSO2)-releasing pads (fast release in the first 48 h and slow for up to 60 days). The ultra-fast SO2-generating pad (FieldSO2) releases the SO2 quickly for up to 6 h, and it was designed to be used soon after the harvest and until the grapes' packaging. The goal was to study the effect of FieldSO2 associated with SlowSO2 and DualSO2 pads on gray mold incidence and physicochemical and appearance characteristics of 'Italia' table grapes. Grapes were harvested from a commercial vineyard in Parana, Brazil, in 2020 and 2021, and packaged in cardboard boxes, and the treatments were as follows: control (without SO2-generating pads); FieldSO2 + SlowSO2; and FieldSO2 + DualSO2. After 30, 45, 60, 75, and 90 days of cold storage (1 ± 1 °C), the grapes were assessed for gray mold incidence, mass loss, shattered berries, stem browning, and filamentous fungi on the surface. The use of FieldSO2 associated with SO2-generating pads is effective in controlling gray mold on 'Italia' table grapes, especially the treatment FieldSO2 + DualSO2, which provides the lowest incidence of the disease up to 90 days of cold storage, while the combination with SlowSO2 results in intermediate efficacy. Treatments combining these SO2-generating pads extend the postharvest shelf life of 'Italia' grapes, with few shattered berries, low mass loss and freshness of the rachis without impairing the bunch's appearance.