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Objectives: The ratio of failures in avionics caused by vibration is considerably high. Reducing the impact of vibrations on the performance of equipment performance is critical. Methods: A PID control based on hybrid optimization algorithm of mutation differential evolution—radial basis function (MDE-RBF) is proposed. During the mutation stage of the MDE algorithm, two sampling and mutation operators are introduced to obtain the dominant individuals for participating in the next-generation. This enables the algorithm to avoid falling in the local optima and improve the global search ability. In the RBF neural network, the data smoothing factor combined with conjugate degree method is used to reduce the fluctuations in the weights during the training process. The MDE-RBF hybrid optimization algorithm combined with PID control is used to shorten the adjustment time of PID and realize the rapid reduction of vibration. The active vibration absorption test of printed circuit board assembly (PCBA) under laboratory conditions, and compared with the standard PID and RBF-PID tests. Results: In the vibration active control test, the MDE-RBF-PID control at different frequencies and voltages showed better damping effect than the standard PID and RBF-PID control. Conclusion: The test results show that the combination of the improved hybrid algorithm and the traditional PID control can quickly suppress the vibration of electronic equipment in the vibration test, and also prolong the service life of the experimental object. [ABSTRACT FROM AUTHOR]

The exploration of low permittivity and dielectric loss microwave dielectric ceramics is particularly important in order to meet the requirements of high-speed massive communication. In this work, new CaSn (BO3)2 ceramics were fabricated by using solid-phase sintering method, and their phase structure, microstructure and dielectric properties were investigated. The sintering temperature has an important effect on microwave dielectric performances of the ceramics. The CaSn (BO3)2 ceramic sintered at 1040 °C exhibited the optimal dielectric properties of εr = 5.20, Q × ƒ = 47,725 GHz, τƒ = − 11 ppm/ °C. [ABSTRACT FROM AUTHOR]

Currently, the development of new packaging substrate materials with low dielectric permittivity, low loss, excellent thermal stability, and chemical stability for meeting 6G massive high-speed wireless communication has always been significant pursuits of many researchers. In this work, the 10 CaO–(25-x)Bi2O3–xAl2O3–60P2O5–5Sb2O3(x = 0−15) glasses were fabricated using melting annealing process. The results indicate that with the increment of Al2O3 content, the numbers of [AlO4] tetrahedron units and metaphosphate Q2 units in the glass structure firstly increase and then decrease, implying an improvement to the glass network structure. Meanwhile, when the content of Al2O3 is 12.5 mol%, the molar volume (Vm) and oxygen molar volume (Vo) of the glass exhibit a minimum value, proving that the most compact glass structure is achieved. The 12.5 mol% Al2O3-added glass sample shows excellent chemical stability and possesses the low dielectric permittivity of 5.0 and the lowest loss of 2.5 × 10–3 as well as the low thermal expansion coefficient of 8.21 × 10–6/°C. These findings reveal that the prepared glass with 12.5 mol% Al2O3 is a potential candidate for electronic packaging field. [ABSTRACT FROM AUTHOR]

The exfoliation of bulk 2H-molybdenum disulfide (2H-MoS2) into few-layer nanosheets with 1T-phase and controlled layers represents a daunting challenge towards the device applications of MoS2. Conventional ion intercalation assisted exfoliation needs the use of hazardous n-butyllithium and/or elaborate control of the intercalation potential to avoid the decomposition of the MoS2. This work reports a facile strategy by intercalating Li ions electrochemically with ether-based electrolyte into the van der Waals (vdW) channels of MoS2, which successfully avoids the decomposition of MoS2 at low potentials. The co-intercalation of Li+ and the ether solvent into MoS2 makes a first-order phase transformation, forming a superlattice phase, which preserves the layered structure and hence enables the exfoliation of bulk 2H-MoS2 into bilayer nanosheets with 1T-phase. Compared with the pristine 2H-MoS2, the bilayer 1T-MoS2 nanosheets exhibit better electrocatalytic performance for the hydrogen evolution reaction (HER). This facile method should be easily extended to the exfoliation of various transition metal dichalcogenides (TMDs). [ABSTRACT FROM AUTHOR]

Purpose: Whether chronotype affects the health outcomes of night shift work populations is unknown. This study aimed to assess the influence of different chronotypes in the rotating night shift population on sleep status, mood, blood pressure (BP), and heart rate variability (HRV), as well as the circadian rhythm of BP and HRV. Methods: A total of 208 rotating night shift workers were included. All participants completed structured questionnaires to assess chronotype, mood and sleep status. During their daily lives outside of the night shift, they underwent 24-hour Holter electrocardiogram monitoring and 24-hour ambulatory blood pressure monitoring. Day-time and night-time BP and BP dipping were obtained. Day-time and night-time HRV values (SDNN, RMSSD, LF, HF, LF nu, SD1, SD2 and SD2/SD1) were calculated and fitted to the cosine period curve. Three circandian parameters (mesor, amplitude and acrophase) were extracted to quantify the circadian rhythm of the HRV indices. Results: Among all three groups, E-type showed more fatigue and sleepiness. In addition, E-type showed blunted diastolic BP dipping. Notably, E-type showed association with higher RMSSD, LF, HF and SD1 in the night time, and higher mesors of RMSSD and LF and amplitude of SD2/SD1 in circadian analysis. Conclusion: Chronotype is a factor affecting fatigue, sleepiness and cardiovascular circadian rhythms of rotating night shift workers. Chronotype should be taken into consideration for managing night-shift rotation to promote occupational health. [ABSTRACT FROM AUTHOR]

A set of Ca2ZnSi2O7:Eu3+ and Ca2ZnSi2O7:Eu3+, Al3+ red phosphors were prepared by the solid-phase reaction method. With 394 nm as the excitation wavelength, all samples were characterized by two major emission bands around 618 nm (5D0→7F2) and 702 nm (5D0→7F4). Ca2ZnSi2O7:0.03Eu3+ phosphor exhibits the best luminescence intensity and its luminescent property is consumed enhanced by doping with Al3+. The quantum yield (QY) of Ca2ZnSi2O7:0.03Eu3+ and Ca2ZnSi2O7:0.03Eu3+,0.03Al3+ reaches 77.79% and 81.73%, respectively. In addition, Ca2ZnSi2O7:0.03Eu3+ and Ca2ZnSi2O7:0.03Eu3+,0.03Al3+ samples exhibit good photothermal stability. The color coordinates of Ca2ZnSi2O7:0.03Eu3+ are (0.641,0.358) with a color purity of 91.97%. Doping by Al3+ has little influence on the color coordinate and color purity of Ca2ZnSi2O7:0.03Eu3+. The above finding reveals that the prepared phosphors have great potential for application in indoor plant growth light illumination and other fields. [ABSTRACT FROM AUTHOR]

Microsphere 3D structure of Cu/Mn3O4@SC composite was fabricated by pyrolyzing the bimetallic CuMn-MOF, which was composed of Cu2+, Mn2+ and sulfur-containing ligand 2,5-thiophene dicarboxylic acid (H2TDC). The composite of Cu/Mn3O4@SC is used as a high-performance anode material for the lithium-ion batteries cycle exhibiting stable capacities of 715 mAh g−1 after 100 cycles at 200 mA g−1 and outstanding long cycle performance with a reversible capacity of 508 mAh g−1 at 0.5 A g−1 after 500 cycles. The superior performance for the Cu/Mn3O4@SC anode is mainly attributed to the mutual supporting characteristics of heterojunction synergistic effect, thus avoiding damage in the process of energy storage process. In addition, the kinetic analysis based on CV reveals that the transport kinetics mechanism of the Cu/Mn3O4@SC is synergistically controlled by the surface capacitive and pseudocapacitive behaviors. The EIS proves that the introduction of Cu enhances the conductivity of the material and the rate of lithium-ion diffusion. Cu- and S-doped multielement microspheres was fabricated by pyrolyzing CuMn-MOF supported by 2, 5-thiophene dicarboxylic acid. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the leading cause of dementia worldwide, with recent studies highlighting the potential role of immunogenic cell death (ICD) in the pathogenesis of this neurodegenerative disorder. A total of 52 healthy controls and 64 patients with AD were included. Compared to the controls, the patients with AD exhibited 2392 differentially expressed genes (DEGs), of which 1015 and 1377 were upregulated and downregulated genes, respectively. Among them, nine common genes were identified by intersecting the AD-related module genes with the DEGs and ICD-associated genes. Gene ontology (GO)analysis further revealed "positive regulation of cytokine production" as the most significant term. Moreover, the enriched molecular functions were primarily related to the inflammatory body complex, while the overlapping genes were significantly enriched in lipopolysaccharide binding. Kyoto encyclopedia of genes and genomes (KEGG) analysis also indicated that these overlapping genes were mainly enriched in immunity, inflammation, and lipid metabolism pathways. Furthermore, the following four hub genes were detected using machine learning algorithms: P2RX7, HSP90AA1, NT5E, and NLRP3. These genes demonstrated significant differences in expression between the AD and healthy control groups (P < 0.05). Additionally, the area under the curve values of these four genes were all > 0.7, indicating their potential diagnostic value for AD. We further validated the protein levels of these four genes in the hippocampus of 3xTg-AD and C57BL/6J mice, showing P2RX7 and HSP90AA1 expression levels consistent with the previously analyzed trends. Finally, the single-sample gene set enrichment analysis (ssGSEA) algorithm provided additional evidence by demonstrating the crucial role of immune cell infiltration and its link with the hub genes in AD progression. Our study results suggest that ICD-mediated elevation of HSP90AA1 and P2RX7 levels and the resulting induction of tau hyperphosphorylation and neuroinflammation are vital in the AD pathogenic mechanism. [ABSTRACT FROM AUTHOR]

Due to the intricate mechanism of Abbe error's impact on spatial accuracy, the accumulated Abbe error in the traditional spatial accuracy model is difficult to identify and eliminate, resulting in reduced modeling accuracy and limiting accuracy improvement. This paper proposes a data-driven spatial accuracy modeling approach for machine tools under the influence of Abbe error, using a three-axis coupling measurement optical path to directly measure the comprehensive spatial accuracy data of the machine tool containing Abbe error. Firstly, to effectively identify Abbe error in the comprehensive spatial accuracy, an Abbe error quantization function is established, which analyzes its formation mechanism in the measurement process to eliminate Abbe error in the machine tool's spatial accuracy data. Furthermore, to address the issue of limited data samples after eliminating Abbe error, data samples are extended based on the degradation mechanism of machine tool spatial accuracy at different coordinate positions, resulting in a high-precision spatial error model for machine tools. Finally, the experiment is conducted on a three-axis CNC machine tool, with a model accuracy of over 95%. The example application verification demonstrates that the developed model scheme is feasible and effective. [ABSTRACT FROM AUTHOR]

Dense niobate glass ceramics with a principal crystalline phase of KSr2Nb5O15 were obtained via melt-quenching and controlled crystallization technique. The research results reveal that with the crystallization temperature increasing from 800 to 950 °C, the dielectric constant and crystal phase content raise simultaneously. The achieved recoverable energy density (Wrec) displays a continuous increase from 0.61 to 1.23 J/cm3 (@500 kV/cm) with the increment of crystallization temperature from 800 to 950 °C. The glass ceramic obtained at 850 °C exhibits the supreme discharge energy density of 1.82 J/cm3 (@ 700 kV/cm), power density of 192.8 MW/cm3 and energy efficiency of 82%. These findings show that the acquired glass ceramics have potential applications in energy storage fields. [ABSTRACT FROM AUTHOR]

Let f be a cuspidal holomorphic or Maass Hecke eigenform for the modular group SL 2 (Z) . Let L (s , f ⊗ χ) denote the twisted L-function associated to f twisted by a primitive Dirichlet character χ modulo q. In this paper, we obtain a lower bound for the 2kth moment of central values of the twisted L-functions. [ABSTRACT FROM AUTHOR]

A pre-formed martensitic quenching plus inverted multi-step austempering process is performed on a medium-carbon alloy steel: after austenitization, the specimen is cooled to 175 °C below the martensite start temperature (Ms), then raised to the first austempering step at 220 °C for 5 h, followed by the second step at 300 ℃ and held for 3 h. The conventional inverted multi-step austempering process and the one-step austempering process are carried out to form a contrast test. Through pre-formed martensitic quenching plus an inverted multi-step austempering process, the martensite/austenite (M/A) and bainitic ferrite in the microstructure are refined. The total time used for heat treatment is reduced markedly due to accelerating bainitic ferrite formation. This study provides theoretical support for the process design of ultra-fine bainitic steel. [ABSTRACT FROM AUTHOR]

This document is a retraction note from the Journal of Supercomputing regarding an article titled "Applying deep learning in football ankle injury for value of high-power magnetic resonance bioimaging evaluation." The article has been retracted due to concerns identified during an investigation by the publisher. These concerns include compromised editorial handling and peer review process, inappropriate or irrelevant references, and the article not being in scope of the journal or guest-edited issue. The authors have not responded to correspondence regarding this retraction. Springer Nature, the publisher, remains neutral in regards to jurisdictional claims and institutional affiliations. [Extracted from the article]

Bismuth sodium–barium titanate (BNT-BT)-based ceramics with multi-phase coexistence exhibit promising piezoelectricity, while the enhancement mechanism of phase transition on the piezoelectricity is worthy of further study. Here, we developed a new composition of (Bi0.5Na0.5)0.94Ba0.06Ti1-x(Nb0.5Lu0.5)xO3 (named as BNTBT-xNL) by introducing (Nb0.5Lu0.5)4+ complex ions to reduce the driving field from P4bm to R3c. A large electro-strain of 0.48% (piezoelectric stain coefficient d33* = 686 pm/V) is obtained in x = 0.15 ceramics. With further studying the properties between poled and unpoled x = 0.15 ceramics, both the intrinsic and extrinsic contribution increased together with the coexistence of R3c and P4bm phase, which are responsible for exploring the origin of the excellent piezoelectric properties of BNT-NL ceramics. In this work, (Nb0.5Lu0.5)4+ complex ions are used to lower phase transition energy barriers and enhance the piezoelectric characteristics of BNT-based ceramics. Rayleigh analysis provides an effective way to quantify the impact of intrinsic and extrinsic contributions on the piezoelectric properties of ceramics. The mechanism and Rayleigh analysis of piezoelectric response in BNTBT-xNL ceramics. [ABSTRACT FROM AUTHOR]

Highlights: A symbiotic host of porous graphite layer is designed as hybrid Li anode for Li ion intercalation and subsequent uniform plating. An ultrahigh plating reversibility of 99.5% is achieved in the carbonate electrolyte. An air-stable cathode prelithiation agent is introduced to provide extra Li source, resulting high energy density of the as-developed practical hybrid Li-ion/metal full cell.The energy density of commercial lithium (Li) ion batteries with graphite anode is reaching the limit. It is believed that directly utilizing Li metal as anode without a host could enhance the battery’s energy density to the maximum extent. However, the poor reversibility and infinite volume change of Li metal hinder the realistic implementation of Li metal in battery community. Herein, a commercially viable hybrid Li-ion/metal battery is realized by a coordinated strategy of symbiotic anode and prelithiated cathode. To be specific, a scalable template-removal method is developed to fabricate the porous graphite layer (PGL), which acts as a symbiotic host for Li ion intercalation and subsequent Li metal deposition due to the enhanced lithiophilicity and sufficient ion-conducting pathways. A continuous dissolution-deintercalation mechanism during delithiation process further ensures the elimination of dead Li. As a result, when the excess plating Li reaches 30%, the PGL could deliver an ultrahigh average Coulombic efficiency of 99.5% for 180 cycles with a capacity of 2.48 mAh cm−2 in traditional carbonate electrolyte. Meanwhile, an air-stable recrystallized lithium oxalate with high specific capacity (514.3 mAh g−1) and moderate operating potential (4.7–5.0 V) is introduced as a sacrificial cathode to compensate the initial loss and provide Li source for subsequent cycles. Based on the prelithiated cathode and initial Li-free symbiotic anode, under a practical-level 3 mAh capacity, the assembled hybrid Li-ion/metal full cell with a P/N ratio (capacity ratio of LiNi0.8Co0.1Mn0.1O2 to graphite) of 1.3 exhibits significantly improved capacity retention after 300 cycles, indicating its great potential for high-energy-density Li batteries. [ABSTRACT FROM AUTHOR]

The Selberg's limit theorem asserts that under an appropriate normalization, the logarithm of the Riemann zeta-function log ζ (1 2 + i t) on the critical line is normally distributed. A spectral analog on the imaginary part of log L (1 2 + i t , ϕ) over a family of GL(2) (resp. GL(3)) Hecke–Maass cusp forms ϕ is developed by Hejhal and Luo [4] (resp. Liu and Liu [9]) using the Kuznetsov trace formula. In this paper, we study the case of GL(n), n ≥ 3 , with the automorphic Plancherel density theorem of Matz and Templier. [ABSTRACT FROM AUTHOR]

Let f(z) be a holomorphic Hecke eigenform of even weight k for SL(2, ℤ), and denote by L(s, symmf) the corresponding symmetric power L-function associated with f. Denote by ⋋symmf (n) the nth normalized coefficient of L(s, symmf). In this paper, we investigate the sum Σn≤x⋋symmf (n) for m ≥ 2 and get the uniform upper bound extending the previous results. [ABSTRACT FROM AUTHOR]

The purplish-red rod-like crystal structure of novel bimetallic metal–organic-frameworks (MOF) {CoZn[(4,4′-BDA)(Phen)]2}n has been obtained by the reaction of Co2+, Zn2+ (the molar ratio Co: Zn = 1:1), 1,10-phenanthroline (Phen) and 4, 4′-biphenyldicarboxylic acid (4,4′-H2BDA), in which Zn ions of the previously reported monometallic MOF {[Zn(4,4′-BDA)(Phen)]2·(HCON(CH3)2}n are partly substituted by Co ions. The crystal structure of {CoZn[(4,4′-BDA)(Phen)]2}n has been characterized by IR, X-ray photoelectron spectroscopy (XPS), and single-crystal X-ray diffraction analysis. Then, the precursors CoZn-MOF-B@C were obtained by adding a surfactant, activated carbon, and NaOH. Its derivative ZnO/CoO@C was used as anode material for lithium-ion batteries, which showed good lithium storage performance. The initial discharge specific capacity of ZnO/CoO@C is 1437.9 mAh g−1 at a current density of 0.2 A g−1, and after 100 cycles, the specific capacity drops to 741.8 mAh g−1. [ABSTRACT FROM AUTHOR]

The SrWO4 + x wt.%Li2WO4(0 ≤ x ≤ 1.5) ceramics with low dielectric constant and high quality factor (Q×f) were fabricated. The impacts of Li2WO4 on sintering, structure, and microwave performance were also investigated. The results exhibit that the appropriate amount of Li2WO4 addition can lower sintering temperature and improve the densification of ceramics. All ceramic specimens adopt a tetragonal scheelite structure and can be sintered below 950 °C. The relative density and polyhedral deformation of SrO8 determine the dielectric properties of the sintered ceramics. The 1.0-wt% Li2WO4-added SrWO4 ceramic sample sintered at 875 °C for 2 h reveals satisfactory characteristics with Q×f = 88,893 GHz, εr = 8.4, and τf = −48.7 ppm/°C. Moreover, the ceramic material is well compatible with Ag electrodes. These findings demonstrate that the as-prepared SrWO4-based materials have great potential for low-temperature co-fired ceramics. [ABSTRACT FROM AUTHOR]

A new type of ternary molybdate ceramic Li1.6Mn2.2(MoO4)3 was manufactured through solid-state reaction. The experimental results exhibit that the changes in microstructure and dielectric property of the ceramic samples depend on sintering temperatures. At microwave frequency of 13.4 GHz, Li1.6Mn2.2(MoO4)3 ceramics sintered at 580 °C possess a supreme density of 3.88 g/cm3 together with the best comprehensive properties of εr = 4.75, Q × f = 30,434 GHz and τf = − 54 ppm/°C, and the prepared ceramic can be co-fired with Al and Ag metal electrodes, which is suitable for ultralow temperature co-fired ceramics (ULTCC) technology. [ABSTRACT FROM AUTHOR]

Transition metal oxides (TMOs) applied to lithium-ion batteries have attracted increasing attention, but volume expansion during charging and discharging makes their application undesirable. To solve this problem, this paper reports for the first time that core–shell copper-manganese oxide nanoparticles, namely M-CuMn-600, consisting of metal oxides encapsulated in a carbon shell, were obtained by calcining a copper-manganese metal–organic framework (named CuMn-MOF) with pyromellitic acid (PMA) as a ligand at 600℃ under an inert atmosphere for lithium-ion battery applications. The M-CuMn-600 anode material was characterized by X-ray diffraction, field emission scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) theory, and X-ray photoelectron spectroscopy (XPS). It has an excellent cycle stability and reversible capacity (709.1 mA h g−1 after 100 cycles at a current density of 200 mA g−1) as an anode material for lithium-ion batteries. The results show that tailoring and optimizing the structure of TMOs is the key to having excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

The Abbé error is a key factor for high-precision CNC machine tools. Unluckily, it is not taken into account in traditional machine tool volumetric error models. In this respect, based on the traditional machine tool volumetric error models, a new machine tool volumetric error model containing Abbé error is performed by analyzing the mechanism of Abbé error formation tool volumetric and based on 21-item geometric error measurement data, Abbé arm, and angle functional relationship. Moreover, integrated qualitative and quantitative simulation method for evaluation of machine tool space precision are correspondingly presented. Finally, an example was utilized to further verify the value of our model by means of analysis and comparison of the tooling precision prior to and after performance of compensation, and its validity and feasibility were proved. This study provides an important modeling method for high-precision machine tools and has very important theoretical significance and practical value. [ABSTRACT FROM AUTHOR]

NASICON-type structured compound Li1.3Al0.3Ti1.7(PO4)3 (LATP) was regarded as a potential solid electrolyte material due to its high ionic conductivity. Herein, the sintering properties, microstructure and ionic conductivity behavior of Li1.3Al0.3Ti1.7(PO4)3/50Li2O–50P2O5(LATP/LP) glass ceramics, prepared through a solid phase method, were investigated for lithium battery applications. The influences of sintering temperatures and LP contents on the microstructure, phase composition and electrical properties of glass ceramics were systematically studied using DSC, TG, XRD, SEM, Raman spectroscopy and impedance spectroscopy. The results show that main crystal phase LiTi2(PO4)3 exists in all glass ceramic samples, and no derivative phase is observed. The addition of LP frits improves the sintering of ceramics and increases the density, but does not change the crystal structure. Especially, the 3 wt% LP added glass ceramic sintered at 850 °C exhibits the highest ionic conductivity of 8.2 × 10–4 S/cm and a low activation energy of 0.263 eV. These as-prepared glass ceramic solid electrolytes have a potential application in lithium batteries. [ABSTRACT FROM AUTHOR]

Binary metal oxide with high theoretical specific capacities is attracting more attentions as anode materials for high performance lithium-ion batteries. Nevertheless, the large volume changes during cycles greatly hamper the actual application of anode materials in lithium-ion batteries. Herein, a new Co Mn metal organic framework (CoMn-MOF) with ligands of 3, 5-Pyridinedicarboxylic acid (H2pdc) and 1,10-Phenanthroline (Phen) was synthesized using a simplistic one-step hydrothermal approach based on previously reported of Co-MOF. At the same way, add activated carbon to generate CoMn-MOF/C followed by calcination in an inert atmosphere and then Mn Co metal oxide (Marked as HP-MnCo2O4/C) nanomaterials were obtained. The superior electrochemical performance is attributed to the nanoparticles on the surface of HP-MnCo2O4/C; many nanoparticles are connected to each other to form a stable conductive carbon network which facilitates sufficient contact between the electrolyte and the electroactive sites and provide more buffer space for volume change during charge and discharge process. Therefore, the HP-MnCo2O4/C anode shows good lithium storage and stable long-life cyclic performance, provided with a high capacity of 355 mA h g−1 at 1000 mA g−1 after 500 cycles. [ABSTRACT FROM AUTHOR]

For closed-channel microfluidic chips, a layer of the cover plate is usually bonded to the substrate layer to enclose the fabricated microstructures on the surface of the substrate. Various irreversible and reversible bonding approaches have been invented for glass, thermoplastic, and PDMS-based microfluidic devices in the recent decade, including anodic bonding, thermal fusion bonding, chemical solvent assisted bonding, sandwich adhesion layer, and oxygen plasma treatment. Currently, most of the reversible bonding methods have to make compromise on bonding strength to achieve the reversible bonding between the substrate and cover plate. In this study, a novel reversible bonding method is proposed with the help of a UV curable release tape, compared with previous methods on reversible bonding using a magnetic or adhesive layer, the proposed method offers a higher bonding strength and easily debond with a simple UV exposure process. The proposed reversible bonding method using UV release tape is inspired by the application of UV release tape in the wafer dicing process in MEMS and IC industry. For the demonstration of the proposed reversible bonding method for microfluidic devices, conventional and hybrid reversible bonding between thermoplastics and glass were achieved, the bonding strength was also measured with different UV radiation doses, the biocompatibility of the UV release tape was tested, finally, several microfluidic devices were fabricated with the proposed reversible bonding method. [ABSTRACT FROM AUTHOR]

This study was to evaluate the performance of magnetic resonance imaging (MRI) reconstruction algorithm based on convolutional neural network (CNN) in the diagnosis of ankle injury of football player. An MRI image reconstruction algorithm based on CNN (CNN-MRI) was constructed, and it was compared with the generalized autocalibrating partially parallel acquisitions (GRAPPA), iterative self-consistent parallel imaging reconstruction from arbitrary k-space (SPIRiT), and simultaneous autocalibrating and k-space estimation (SAKE) in MRI image of patients with ankle injury. They were compared regarding MRI image reconstruction quality (image score, peak signal-to-noise ratio (PSNR), structural similarity (SSIM), root mean square error (RMSE), and running time) and the assessment accuracy for each lesion. The detection rate of ankle joint injury and evaluation accuracy of the bone contusion, ligament injury, tendon injury focus, and different stages of osteochondral injury of the patients were recorded. The reconstructed image score, PSNR, SSIM, RMSE, and running time were calculated accordingly. The results showed that the detection rates of osteochondral injury (97.58%), joint effusion (91.21%), and soft tissue swelling (93.47%) in the CNN-MRI group were higher than those in GRAPPA (81.14%, 74.24%, and 76.11%), SPIRiT (80.66%, 73.66%, and 74.87%), and SAKE (86.96%, 82.61%, and 80.5%) groups (P < 0.05). The number of patients with 5 scores of reconstructed images in the CNN-MRI group (19 cases) was remarkably higher than that in GRAPPA (12 cases), SPIRiT (11 cases), and SAKE groups (14 cases) (P < 0.05). PSNR and SSIM of reconstructed image of patients in CNN-MRI group were much higher in contrast to those in GRAPPA, SPIRiT, and SAKE groups (P < 0.05), while the RMSE and running time were much lower than other algorithms (P < 0.05). In addition, the accuracy of evaluating the osteochondral injury in stage I and stage II for the patients in the CNN-MRI group was obviously higher than that in GRAPPA, SPIRiT, and SAKE groups (P < 0.05). In short, CNN-MRI algorithm could greatly improve the quality and PSNR of MRI reconstructed images, shorten the running time, and had excellent performance in showing the details of tendon injury, ligament injury, and bone contusion lesions. Moreover, it had a good effect on image processing of football players, could improve the accuracy of the diagnosis of ankle joint injuries, and could assist clinicians in the imaging diagnosis of ankle joint injuries of the football players. [ABSTRACT FROM AUTHOR]

Unique structure and performance in prominent high-entropy ceramics (HECs) have attracted enormous attentions recently. In this work, we have successfully synthesized pure-phase (Bi1/6Na1/6Sr1/6Ba1/6Pb1/6Ca1/6)TiO3 (BNSBPC) and (Bi1/6La1/6Na1/6K1/6Sr1/6Ba1/6)TiO3 (BLNKSB) HECs by conventional solid-state method. Rietveld refinement results show that BNSBPC composition possesses tetragonal phase (P4mm) while the BLNKSB one exhibits cubic phase (Pm 3 ¯ m). Dielectric characterization reveals distinct relaxation behaviors between BNSBPC and BLNKSB compositions. Relaxor-like nature in BNSBPC and Debye medium in BLNKSB one are verified by dielectric, ferroelectric and Raman spectra characterizations. Maximal electrocaloric effect (ECE, ΔTmax) reaches 0.63 K with relatively narrow temperature span (ΔTspan) of ~ 20 K at 60 kV cm−1 for BNSBPC ceramic, while the BLNKSB one possesses superior temperature stability (ΔTspan = 100 K) with ΔTmax = 0.14 K. Room-temperature ECE is also obtained by home-made adiabatic calorimeter, which indicates a positive ECE for both compositions. Finally, phase structure, dielectric properties and ECE in two high-entropy compositions are comparatively discussed to explore structure–ECE relationships in HECs. The superior thermal stability of ECE in BLNKSB samples provides a broad prospect for designing solid-state refrigeration. [ABSTRACT FROM AUTHOR]

Considering the problems of communication overhead between nodes and the challenges brought by large-scale complex network in distributed system cluster management, we propose a local community detection algorithm in complex network called FLCDA (Fast Local Community Detection Algorithm). FLCDA can detect communities in a large-scale complex network on a single PC. The algorithm uses a Parallel Sliding Windows (PSW) method to break a large-scale network into smaller sub-networks, and load sub-network into a PC memory. This method conforms to the local characteristics of the community. FLCDA first finds out disjoint Maximum Influence k-clique in each sub-network, and then assigns the same label and weight to all nodes in the same Maximum Influence k-clique. These labels and weights are used as seeds at the label propagation phase of FLCDA. During the labeling propagation phase, FLCDA applies a synchronous update strategy while removes meaningless labels after each iteration. When all node labels are updated, the update process will be ended. This method can reduce the calculation cost and improve the stability. The experiment results show that non-parameter FLCDA can self-adaptively detect communities on various scales and types of complex networks. By comparing with other algorithms, FLCDA has gained higher community detection accuracy and less running time. Therefore, FLCDA algorithm can be better adapted to community detection in real complex networks without prior knowledge. [ABSTRACT FROM AUTHOR]

The influence of B-site complex ions substitution on the dielectric and piezoelectric properties of (Bi0.5Na0.5)0.93Ba0.07Ti1–x(W0.5Mg0.5)xO3 (BNBT–xWM) ceramics was studied in detail. X-ray diffraction patterns revealed that B-site substitution resulted in a phase transition from the tetragonal phase to pseudocubic phase. Ferroelectric to relaxor (FE-RE) phase transition temperature TF-R decreased with increasing (W0.5M0.5)4+ dopants, finally below room temperature. The destabilization temperature of piezoelectric constant d33, together with ferroelectric response was decreased with increasing x. However, the strains could be significantly enhanced with the addictive of (W0.5M0.5)4+, and a large strain of 0.325% with a normalized strain, d33* of 541.7 pm/V could be achieved for x = 0.04 ceramics [ergodic relaxor (ER) dominant]. The enhanced strains might attribute to the composition-induced NR–ER transition and high dynamic polar-nanoregions (PNRs), which strongly affecting piezoelectric and dielectric properties. [ABSTRACT FROM AUTHOR]

Anthracite sheets were coated by sorbitol fatty acid ester (span80) through ball-milling process. The tribological properties of the span80-coated anthracite sheets as the additive in polyalpha olefin were evaluated through a series of friction tests using a four ball machine. The results revealed that the span80-coated anthracite sheets exhibited excellent dispersion stability in base oil. In addition, compared with base oil, the average coefficient of friction, wear scar diameter, and wear volume of modified oil at a mass fraction of 0.03% span80-coated anthracite sheets decreased by 45.39%, 60.13%, and 95.95%, respectively. The oil containing span80-coated anthracite sheets achieved good friction-reducing and anti-wear effects over a wide range of applied loads, temperatures, or rotating speeds. Control experiments were performed as well. The results obtained using span80-coated anthracite sheets were superior to those obtained using pure anthracite. The lubrication mechanism was attributed to the synergistic action of the crystalline and amorphous carbon in anthracite sheets as they formed a protective film and played a mitigative role on the surface of friction pair, which mitigated the wear extent of the friction pair. [ABSTRACT FROM AUTHOR]

This paper describes the development of a three-dimensional (3D) physics-based fire simulation model that employs the incompressible Navier–Stokes equations to realistically emulate the combustion process. Then, we animate the 3D interactive burning processes by rendering a flame under a set of influence factors and with various solid boundaries and obstacles. It is insufficient to simply create a virtual reality-based fire model. Instead, evaluating the similarity and accuracy of the models requires data processing for the virtual flames. In this paper, detailed data are extracted from the simulation results to compute the fire's geometrical features and the distribution of the density and velocity fields. Using methods for video-based fire detection, some visual features of the simulated-fire videos are extracted and compared with those of real fires. The results show the capability of the physics-based fire model in representing some features of real flames. The proposed quantitative analysis of virtual flames serves to evaluate the similarity between a virtual and a real fire. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the efficacy of Chinese herbal medicine (CHM) in patients with severe/critical coronavirus disease 2019 (COVID-19). In this retrospective study, data were collected from 662 patients with severe/critical COVID-19 who were admitted to a designated hospital to treat patients with severe COVID-19 in Wuhan before March 20, 2020. All patients were divided into an exposed group (CHM users) and a control group (non-users). After propensity score matching in a 1:1 ratio, 156 CHM users were matched by propensity score to 156 non-users. No significant differences in seven baseline clinical variables were found between the two groups of patients. All-cause mortality was reported in 13 CHM users who died and 36 non-users who died. After multivariate adjustment, the mortality risk of CHM users was reduced by 82.2% (odds ratio 0.178, 95% CI 0.076–0.418; P < 0.001) compared with the non-users. Secondly, age (odds ratio 1.053, 95% CI 1.023–1.084; P < 0.001) and the proportion of severe/critical patients (odds ratio 0.063, 95% CI 0.028–0.143; P < 0.001) were the risk factors of mortality. These results show that the use of CHM may reduce the mortality of patients with severe/critical COVID-19. [ABSTRACT FROM AUTHOR]

(1-x)BaWO4-xTiO2 (x = 0.00, 0.05, 0.10, 0.15, 0.20, 0.25, BWT) ceramics were prepared by traditional solid-state method. The XRD patterns indicate that the BWT ceramics exist as composites, and the Raman spectra show that as TiO2 increases, the vext mode shifts to a low wavenumber and the Ba–O bond length decreases. The variations in FWHM values of the v3(Eg) modes and c/a values indicate the changes in the ordered structures that lead to the increase in dielectric loss. The infrared spectra were fitted by the FPSQ model, and the external mode (Eu) contributes most to the dielectric properties, which is related to the Ba–O bond vibration. With the increase in x values, the τf values increase from − 101.61 to − 6.71 ppm/°C, the εr values increase from 8.03 to 9.49, and the 0.75BaWO4–0.25TiO2 ceramic with stable temperature coefficient was obtained: εr = 9.49, Q × f = 20,602 GHz (f = 17.99 GHz), τf = − 6.71 ppm/°C. [ABSTRACT FROM AUTHOR]

Non-stoichiometric Nd[Mg0.5Sn0.5(1+x)]O3 (− 0.04 ≤ x ≤ + 0.04)—type samples were prepared using a traditional two-step solid-state sintering process. Their crystal structures, phase compositions, dielectric properties and lattice vibrational characteristics were identified in detail. The double perovskite Nd(Mg0.5Sn0.5)O3 with a monoclinic structure was distinguished as the main crystalline phase, and pure phase was obtained when x < 0. The sample [Nd(Mg0.5Sn0.49)O3] at x = − 0.02 shows the excellent dielectric properties: εr = 18.74, Q × f = 47,979 GHz. The lattice vibrational characteristics were clarified with Raman and infrared active mode spectroscopy. The intrinsic properties were fitted by four-parameter semi-quantum model, which show that the low-frequency infrared modes yield a more significant contribution to permittivity and dielectric loss. Raman shifts of modes F2g(A) and F2g(B) correlate with dielectric constants negatively, which implies that the bond length has a positive correlation with permittivity. Full widths at half maximum of vibrational modes A1g(O) correlate with dielectric loss values positively and correlate with the degree of order (S) negatively. [ABSTRACT FROM AUTHOR]

The development of ferroelectric (FE) ceramics with high recoverable energy-storage density (Wrec) critically affects the miniaturization and integration of advanced pulse-power capacitors. However, most lead-free FE materials have the shortcomings of large remanent polarization and low dielectric breakdown strength. In this work, a strategy of composition control was implemented to improve the Wrec of lead-free ceramics. The effects of Li and Nb ion incorporation on the structure, dielectric, and ferroelectric properties of the highly insulating (Na0.5Bi0.5)TiO3–BaTiO3 (NBT–BT) ceramic was investigated. X-ray diffraction analysis of the samples revealed that the pure phase was isostructural to (Na0.5Bi0.5)TiO3. Dielectric measurements exhibited two pronounced anomalies which shift a certain angle within the depolarization-temperature range. The effects of LiNbO3 content on the breakdown characteristics and discharge energy storage of NBT–BT ceramics were investigated. An enhanced discharged energy density of 1.05 J/cm3, calculated from a hysteresis loop, was observed at x = 4 mol%. The improved structure also resulted in an increase of up to 61% in breakdown strength. [ABSTRACT FROM AUTHOR]

The borate glass–ceramics with a great energy storage density were fabricated using the melt-quenching method and then heat-treated technology. The microstructure, dielectric properties, energy storage properties and charge–discharge behavior were discussed. The dielectric constant increases monotonically with the increase of crystallization temperature, but the breakdown strength and energy storage density show a trend of increasing first and then decreasing, which is opposite to the activation energy reflecting the interfacial polarization. When the crystallization temperature is 750 °C, the activation energy reaches the lowest value. The glass–ceramics heated at 750 °C have the high breakdown strength of 1487 kV/cm, the maximum energy density of 9.61 J/cm3 and high energy efficiency of 89%, while the actual discharge density reaches the maximum value of 0.4811 J/cm3 under a voltage applied of 500 kV/cm, which makes the materials suitable for applications in energy storage, especially in high power and pulsed power systems. [ABSTRACT FROM AUTHOR]

Single phase ZnWO4 microwave dielectric ceramic was prepared by a traditional solid-state method, which possesses the monoclinic wolframite structure. The lattice vibrational modes were obtained by Raman and Fourier-transform infrared (FTIR) spectra, whose phonon characteristics were analyzed by identification and description of the vibrational modes. Furthermore, the intrinsic properties of Single phase ZnWO4 was simulated based on FTIR data, and the contribution of each vibrational mode to the intrinsic properties was analyzed, in particular. The theoretical property values, calculated by the Clausius–Mossotti and damping equations, agree well with the data fitted by the four-parameter semi-quantum model according to FTIR spectrum. [ABSTRACT FROM AUTHOR]

Bactrocera tau (Walker) (Diptera: Tephritidae) is an economically important invasive pest, that is capable of seriously reducing the quality and yield of vegetables and fruits, it was first recorded from Fujian province in 1849 and later introduced to Yunnan province in 1912 as a result in trade fruits and vegetables of China. In recent years, with the onset of global climate change and the accompanying increase in the greenhouse effect, elevated climatic temperatures have become one of the main environmental factors affecting growth and reproduction in insects, and the optimal developmental temperature of B. tau was found to be from 25 °C to 31 °C, the growth, development and reproduction of B. tau are normal under the optimal temperature conditions. In order to determine the repercussions that elevated temperature have on B. tau, we assessed the effects that short-term (12 h) high-temperature exposures (34 °C, 36 °C, 38 °C, 40 °C, 42 °C, 44 °C, 46 °C, and 48 °C) had on the growth, development and reproduction of B. tau at different developmental stages of the fly. The results showed that the survival rate of B. tau gradually decreased in all stages following exposure to short-term high-temperatures. The pupal stage was the least sensitive to increased temperatures. The pupae withstood the highest lethal temperature, having an LT50 of 42.060 °C, followed by female adults (40.447 °C), male adults (40.013 °C), and larvae (36.740 °C). The egg stage, which was the most susceptible to heat increases, had the lowest LT50 (38.310 °C). No significant effects were observed in the developmental stages of B. tau at temperatures from 24 °C to 38 °C. The development duration was significantly prolonged at 40 °C (P < 0.05) in the eggs (2.830d), larvae (7.330d), and pupae (8.170d) (P < 0.05). B. tau was unable to survive at temperatures above 42 °C. The pre-oviposition of female adults was extended, the average egg number per female showed a downward trend, the longevity of adults gradually shortened, and the ratio of female to male offspring increased as temperature increments were increased. In summary, short-term high-temperatures over 42 °C were not suitable for successful development of B. tau, while short-term high-temperatures over 40 °C were not suitable for successful reproduction in B. tau. [ABSTRACT FROM AUTHOR]

(1 − x)[0.9(Bi0.5Na0.5)TiO3–0.1BiScO3]–xBaTiO3 (BNT–BS–xBT) ceramics are prepared by the traditional solid-state sintering. The structure, morphology, ferroelectricity, strain, energy storage, dielectricity, and impedance of the BNT–BS–xBT ceramics are investigated. XRD shows that all ceramics have pseudo-cubic structures. The results also show that BT can refine the grain size of the ceramics and reduce the corresponding density. At x = 0.20, the energy storage performance of the ceramics is optimum (Wrec = 0.563 J/cm3, η = 63%). At x = 0.10, the electrostriction coefficient (Q33) of the ceramics reaches 2.72325 × 10−2 m4/C2. Dielectric and impedance spectroscopies show that the ceramics are relaxor ferroelectrics and have good insulation properties. [ABSTRACT FROM AUTHOR]

Research on failure law of target oil storage tank subjected to the coupling impact of multiple blast waves is one of the theoretical bases for domino effect accident prevention and control of chemical industrial parks. Taking the coupling impact of two-source blast waves as an example, the propagation law of blast waves in air and the distribution law of peak overpressure on the surface of tank wall are analyzed, and the dynamic response laws of displacement, stress, strain and energy for a 5000 m3 atmospheric steel arch-roof oil tank are studied by using ANSYS/LS-DYNA. The results are compared with those subjected to single blast wave and show that the maximum overpressure peak value is formed near the ground in 0° direction on the surface of tank wall, which is 79.6% larger than that subjected to single blast wave. The peak values of displacement, stress and strain for the tank wall subjected to the coupling impact of two-source blast waves are 114.9%, 39.6%, 134.9% larger than those subjected to single blast wave, respectively. The failure mode of arch-roof tank subjected to two-source blast waves is to form multiple concave plastic deformation zones on the explosion face, which extend to the surrounding area and produce plastic hinge lines and form irreversible residual deformation and cracking finally. The analysis results can provide reference for explosion-resistant design of tank structure and reasonable layout of tank area scene. [ABSTRACT FROM AUTHOR]

Glass-ceramics materials of SrO-BaO-Nb2O5-B2O3 system have been prepared by conventional melt-casting followed by controlled crystallization. The crystallization kinetics, phase evolution, microstructure, breakdown strength and dielectric properties have been explored by differential scanning calorimetry (DSC), X-ray diffractometer (XRD), scanning electron microscope (SEM), and multifunction LCR meter. The results reveal that crystallization mechanism of this glass is believed to be three-dimensional interfacial growth. It was observed that predominant crystalline phase is Ba0.39Sr0.61Nb2O6 in these glass-ceramics crystallized at 750 °C, and the grain size increases with increase in crystallization time. The uniform microstructure can be seen clearly in glass-ceramics crystallized at 750 °C for 3 h, and the obtained glass-ceramics was found to possess optimal properties. Moreover, glass-ceramic with a dielectric constant of 58, the dielectric loss of 0.007 and breakdown strength of 1010 kV/cm could be achieved. In addition, energy storage density of glass-ceramics reached a maximal value of 2.62 J/cm3. To our knowledge, studies on SrO-BaO-Nb2O5-B2O3 glass-ceramics without SiO2 as a glass network former are few, and the melting temperature of the B2O3-based glass is lower than that of SiO2-based glass, which is conducive to the purpose of energy saving. These findings indicate that this glass may be a candidate for high energy-storage capacitors. [ABSTRACT FROM AUTHOR]

We prepared 15.16SrO–(16.84 − x)BaO–xK2O–32Nb2O5–28B2O3–8P2O5 glass ceramic composites with different K:Ba ratios through melt-casting followed by controlled crystallization. Although the dielectric constant of these samples decreased with an increase in x, a maximum theoretical energy density of 12.83 J/cm3 was obtained at x = 10.104. High breakdown strength (1844 kV/cm) and low dielectric loss (< 0.3%) might be the cause of high energy storage density at x = 10.104. [ABSTRACT FROM AUTHOR]

Suppose that q and r are two distinct large primes. Let g be a cuspidal Hecke eigenform of level 1 and even weight k 1 and H k 2 (q) be the set of cuspidal Hecke eigenforms of level q and even weight k 2 . In this paper, we investigate the averages of the product of the central values of two L-functions of modular forms f ∈ H k 2 (q) and g twisted by all primitive Dirichlet characters modulo r and obtain an asymptotic formula with a power saving error term under certain assumptions. [ABSTRACT FROM AUTHOR]

The capabilities of conductive ink with both excellent conductivity and flexibility properties are extremely important for the construction of next-generation flexible electronic devices. However, the development of an appropriate ink possessing high conductivity and good dispersity remains a big challenge for ink-jet printing. Here, an original synthesis method of surfactant-free carbon black@graphene (CB@rGO) conductive ink is reported via freeze-drying process and reduction in p-phenylenediamine. The CB@rGO ink unambiguously displays a well-defined and smooth morphology, extremely the CB@rGO conductive particles showing good stability in many solvents. The CB@rGO film exhibited outstanding flexibility which is showed by the durable conductivity after bending 1000 times. Furthermore, it has an excellent conductivity of 714 ± 90 S m−1, and these data increased to 5091 ± 200 S m−1 after the high temperature post-processing increased by 198% compared to the traditional rGO film. Notably, the absence of surfactant in conductive fillers' dispersing process contributed to the high conductivity of CB@rGO ink compared with the traditional ones. [ABSTRACT FROM AUTHOR]

In this work, lead-free piezoelectric ceramics Ba0.99Li0.005Al0.005(Ti0.92Sn0.08)O3-0.5%MnO2(BLATS-M) and Ba0.99Li0.005Nb0.005(Ti0.92Sn0.08)O3-0.5%MnO2(BLNTS-M) were synthesized by a solid-state reaction process. The influence of Li+–Al3+, Li+–Nb5+ ionic pairs on the microstructure, phase structure and electrical properties of Ba(Ti0.92Sn0.08)O3-0.5%MnO2(BTS-M) was systematically investigated. An orthorhombic (O) phase structure is obtained in all ceramics at room temperature. Both Li+–Al3+ and Li+–Nb5+ ionic pairs co-doping can enhance the piezoelectricity of BTS-M ceramic, while the Li+–Nb5+ doped BLNTS-M ceramic exhibits an optimum electrical properties: the piezoelectricity coefficient (d33) = 805 pC/N, the electromechanical coupling coefficient (kp) = 0.519, the relative permititivity (εr) = 31900, the converse piezoelectric coefficient d 33 ∗ = 536 pm/V and the in situ quasi-static d33 with maximum d 33 max = 1620 pC/N. The dielectric properties versus DC bias electric field experiments exhibit high dielectric tunability (ƞr = 97.78%) and figure of merit (FOM = 20.96) at 100 Hz and room temperature in BLNTS-M ceramic. The results suggest an effective approach to design high-performance piezoelectrics and dielectrics by appropriately selecting the types of donor–acceptor ionic pairs. [ABSTRACT FROM AUTHOR]