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For the first time, a MgAl2O4 transparent ceramic cylindrical dielectric resonator antenna (DRA) is designed using the fundamental HE11δ modes for slot excitation. The transparent microwave dielectric ceramic was synthesized using high-purity MgO and γ-Al2O3 powders by aqueous gel-casting combined with cold isostatic pressing, pressure-less sintering and hot isostatic pressing methods. Optimum relative permittivity ∼8.2, Q × f (Q = quality factor = 1/dielectric loss, f = resonant frequency) ∼110 510 GHz and temperature coefficient of resonant frequency ∼−74.1 ppm °C−1 were obtained. The reflection coefficient, the input impedance, the antenna gain and the radiation pattern of the transparent cylindrical ceramic DRA were examined, and it was observed that the simulation results were in reasonable agreement with the measurement results. It has been found that the proposed transparent cylindrical MgAl2O4 ceramic DRA can provide a higher impedance bandwidth (BW = 735 MHz) and radiation efficiency (95.8%) than a state-of-the-art transparent glass DRA. The proposed configuration can potentially be used for such useful antenna decoration and can be used as a lampshade to integrate these antennas in street and traffic lights without compromising the aesthetics of the city.

The origin of the quantum superconductor to metal transition at zero temperature in two-dimensional superconductors is still an open problem, which has caused intensely discussion. Here, we report the observation of a quantum superconductor-to-metal transition in LaAlO3/KTaO3 (111) interface, driven by magnetic field. When a small magnetic field perpendicular to the film plane is applied, the residual saturated resistance is observed, indicating the emergence of an anomalous metallic state associated with a failed superconductor. The dependence of saturated resistance on magnetic field at low temperature indicates that the observed metal state is a Bose metal state. From our findings, magnetic field regulating LaAlO3/KTaO3 (111) interface emerges as a platform to scrutinize the details of the anomalous metallic state in a controllable way.

Transparent material has been widely used in product design and has seen a large increase in its use. In this paper, a kind of aesthetically decorative 5 GHz Wi-Fi dielectric resonator antenna (DRA) of aluminum oxynitride (AlON) transparent ceramic has been designed. High-quality-factor AlON transparent dielectric ceramics were fabricated by presintering at 1780 °C and further cold isostatic pressing (CIP) under a 200 MPa argon atmosphere. For a 9.0 mm thick specimen, the in-line light transmittance reached 83%. Optimum dielectric constant (er = 9.32), quality factor (Qf = 47 960) and temperature coefficient (TCF = -51.7 ppm/°C) was achieved in the AlON transparent ceramic by cold isostatic pressing. As a result, the proposed aesthetically decorative DRA can achieve an impedance bandwidth of 32% (4.48-6.19 GHz), a high radiation efficiency of 85%, and a low cross-polarization discrimination (XPD) of -30 dB. To achieve a broad bandwidth, the proposed antenna was excited in its dominant TE111x mode and higher-order TE113x mode. The proposed antenna is thus an excellent candidate for an indoor decoration Wi-Fi antenna.

Correlated states emerge in low-dimensional systems owing to enhanced Coulomb interactions. Elucidating these states requires atomic scale characterization and delicate control capabilities. In this study, spectroscopic imaging-scanning tunneling microscopy was employed to investigate the correlated states residing in the one-dimensional electrons of the monolayer and bilayer MoSe2 mirror twin boundary (MTB). The Coulomb energies, determined by the wire length, drive the MTB into two types of ground states with distinct respective out-of-phase and in-phase charge orders. The two ground states can be reversibly converted through a metastable zero-energy state with in situ voltage pulses, which tunes the electron filling of the MTB via a polaronic process, as substantiated by first-principles calculations. Our modified Hubbard model reveals the ground states as correlated insulators from an on-site U-originated Coulomb interaction, dubbed Hubbard-type Coulomb blockade effect. Our work sets a foundation for understanding correlated physics in complex systems and for tailoring quantum states for nano-electronics applications., Comment: 4 figures, 19 pages

Dielectric patch antenna (DPA) has been extensively studied in recent years, especially for the application of 5G mobile communication system. In this paper, we proposed a notch structure of H-shaped DPA (HDPA) with wideband low-profile properties but without additional components. Temperature stable 0.65 CaTiO3–0.35 LaAlO3 microwave dielectric ceramic of high permittivity was utilized for fabricating the H-shaped dielectric patch, and the method of leveraging the multi-modal features of DPA was introduced. Further analysis of the antenna structure was accomplished by the simplified theoretical method. As a result, the H-shaped notch is properly ensembled in the dielectric patch to make the higher-order TM121 mode close to the dominant TM101 mode, greatly expanding the broadband of the HDPA. The accuracy of the proposed HDPA element model is evaluated by the commercial full-wave simulator CST Microwave Studio. For demonstration, a prototype of the proposed HDPA element operating in the microwave band (5-GHz) has been realized and measured.

The purpose of this paper is the development of flame retardant chef coats fabric. The main properties of polysulfonamide fiber are described , the research and development of the product processing of polysulfonamide /Aramid 1313 blended yarn and the union fabric with it and cotton yarn are explored. The technology problems of spinning and weaving are solved. The mechanical property , comfort property and flame retardance of the fabric of polysulfonamide /Aramid 1313 blended yarn and cotton yarn are qualified .The product can be used for high grade chef coats fabric.

In this article, a novel band-notched ultra-wideband (UWB) bandpass fllter based on hybrid microstrip/slotline structure is proposed. A quad-mode stubs-loaded slotline resonator is fed by two orthogonal microstrip lines and ultra-wideband bandpass characteristic is excited. A stub-loaded dual- mode microstrip resonator is externally loaded to the quad-mode slotline resonator, and a notched band with sharp roll-ofi characteristic is achieved. The circuit model for the dual-mode microstrip resonator loaded slotline is given and analyzed. The proposed fllter is designed and fabricated. Simulated and measured return losses are i12dB/i18dB and i18dB/i10dB in lower and higher passband. The return loss in the notched band is greater than 15dB.

In the rolling process, reasonable way of grading and rolling can improve the compactness and anti-permeability of roller compacted concrete (RCC), as well can make its strength meet the design requirements. Vibration liquefaction is the key step for RCC in the rolling process. Therefore, this paper first puts forward the more suitable method, Modified Vebe Vibration Liquefaction Test, to account for the characteristics of vibration liquefaction in RCC, and then, studies the coarse aggregate gradation scope using aggregate gradually filling theory. Though Modified Vebe Vibration Liquefaction Test, the research show that the aggregate VCA and the characteristics of vibration liquefaction of RCC have a good correlation. Finally, by studying the sand ratio and fineness modulus of sand how to affect the performance of liquefied RCC, the optimum value range of sand ratio and fineness modulus of sand was determined.

Firefighter's protective clothing provide protection for the firefighter's torso, neck, arms, and legs, but excluding the head, hands. The performance index for textile burning behaviour include afterflame time, afterglow time, damaged length, damaged area, dimensional stability to heat, ignition time and so on. The purpose of Standard is to provide minimum performance requirements for protective clothing for firefighters, whilst fighting fires. Within national standard GB 8965.1-2009 protective clothing, flame-retardant protection, part 1: flame-retardant protective clothing, the performance requirement are divided into three grade: A grade, B grade, C grade. The performance requirements C grade is the lower level, A grade, the higher level. The level of personal protection chosen should be based on the outcome of a risk assessment. Within national standard GB/T 17591-2006 flame retardant fabrics, assessment criteria are divided into two grade: B1 grade and B2 grade. The performance requirements B2 grade is the lower level, B1 grade, the higher level. Within standard GA 634-2006 protective clothing for proximity fire fighting and GB/T 5444-1997 textiles-burning behaviour-vertical method, the performance requirement are not classification. In different standard, the test parameters, such as the specimen dimension, specimen quantity and the flame height, are different. In order to establish suitable standard system, some effective standard should be revised. The standard system should cover the general clothing design, the minimum performance levels of the materials used, and the methods of test to be used to determine these performance levels. For adequate overall protection against the risks to which firefighters are likely to be exposed, additional personal protective equipment to protect the head, face, hands and feet should also be worn, along with appropriate respiratory protection where necessary.

This paper presents a novel compact microstrip hybrid four-mode bandpass fllter (BPF) with good selectivity and multi- transmission zeros. By adding an external resonator to a triple- mode stub-loaded resonator, four modes are generated in the desired passband and a hybrid four-mode BPF is implemented. Odd- and even-mode theory is introduced to investigate the mode characteristics of triple-mode resonator in detail. Circuit model and coupling matrix are built to further explain the proposed methodology. A microstrip BPF with central frequency of 3.4GHz for wireless communication was designed and fabricated. Three transmission zeros are obtained at 3.2GHz, 3.55GHz and 3.73GHz, which improve selectivity and out- of-band rejection of the fllter. The measured results of the fabricated fllter represent good in-band and sharp sideband characteristic, which match well with simulated results.

Considering the practical problems in the threshing and redrying production, in order to improve the manufacturing process quality, by using twice hot-air tobacco embellishing as the critical process in production flow and applying SPC technology, through the online data collection, this paper analyzed the causes of quality defects in the course of production and made adjustments. The conclusion is that SPC technology ensures the quality stability of the tobacco processing progress, and also strongly improves the process capability, which achieves the 3σ Control of product quality.

3D woven fabric significantly improves the mechanical properties, especially the strength resulting from the between layers connections of yarns Hence, 3D woven fabrics have been widely used as reinforcing material in prefabricated composites, A particular 3D woven fabric with “中” shaped cross section was developed in this study .The fabric was made in a plane loom weaving machine. The designing procedure and processing methods are given in details.

With the development of modern technology, fiberglass composite materials are widely applied. The advantages of fiberglass reinforced composite materials are high strength and light weight. In order to produce a prefabricated fiberglass composite, a machine chart was drafted for weaving the 3D fiberglass fabric with five layers. The obtained five-layer 3D fabrics were composited with polyurethane matrix. Afterwards, the performance of the prefabricated composites was tested and the optimal ratio of fiberglass to matrix was determined by statistical analysis.

No matter for clothes fabric or industry fabric, the water permeability is an important performance indicator. In order to explore relationship of the water permeability of woven filtering fabrics with the fabric structure parameters, we design sixteen fabric. According to the national standards of determination of water permeability of woven filtering fabric, we test the dank ratio of the design fabric. In this paper we analysis the water permeability and structure parameter of woven filtering fabric with test the quality of water on some time through woven fabrics. We calculated the dank ratio from the water permeable quality and other parameters. The results indicate that, the effect of fabric texture on the dank ratio of woven fabrics is that the dank ratio of the plain weave is the smallest and the satin weave is the biggest. In addition, the relationship between overall covering factor and water permeability showed that the water permeability decreases along with the overall covering factor increasing. A linear regression equation between dank ratio and overall covering factor is get from the test results. In order to get big dank ratio, we should produce fabric with satin weave and lower overall covering factor.

Fuzzing and pilling of fabrics, which is one of the factors that affect fabric appearance and wear behaviour, has plagued the people for a long time. With the development of living standard, people have higher and higher requirements on the properties of apparel. Several methods can be used for testing the fuzzing and pilling performance of fabric, and different methods often have different results. Using circular locus method and pilling box method on the four kinds of fabrics at the same time, conduct experimental data processing, compare the advantage and disadvantage of two methods and obtain the principle of selection of them. There are many factors that cause fuzzing and pilling, among which the overall covering factor is a significant one. Through the testing for four different kinds of cotton-wool mixed fabrics, with different warp density and different weft density, establish the relationship between the number of pills and the overall covering factor, and obtain the critical covering factor according to the one factor nonlinear regression equation.

A novel dual-mode bandpass fllter (BPF) using stub- loaded defected ground open-loop resonator is proposed in this article. Defected arrow-shaped stub is loaded to a defected ground open- loop resonator, and two non-degenerate modes are excited for dual- mode characteristics. Based on even- and odd-mode theory, dual- mode characteristics of the resonator is analyzed. Design equations for the defected-ground resonator are investigated. A two-pole dual- mode bandpass fllter operating at 2.4GHz with fractional bandwidth of 7.97% is designed, fabricated, and measured. Good agreement between simulated and measured results verifles the validity of this design methodology.

Digital micro-mirror device (DMD) can be controlled to form Hadamard encoding masks flexibly and efficiently. A kind of Hadamard transform spectral imager of adaptive spectral resolution based on DMD is proposed. The structure and the working principle of the instrument are described and the implementation method of adaptive spectral resolution is analyzed. It can adjust the spectral resolution according to the target and the observational requirements, and a reasonable compromise can be reached between the spectral accuracy and the computation of data. It not only meets the requirements of the target classification and recognition, but also improves the speed of data transmission and processing.

A novel type of DMD-based Hadamard transform spectral imager is introduced. Taking the 7-order S-matrix as an example for discussion, the present paper develops an improved design of Hadamard encoding mask, which makes the dispersed spectrum of all pixels to be encoded by seven elements strictly. A correcting method for the recovered spectral images is proposed, and eventually 6 high-quality spectral images are obtained when Hadamard transform spectral imager operates based on 7-order S-matrix. Similarly, if the spectral imager operates based on n-order S-matrix, n--1 spectral images can be obtained. The experimental results show that the improved design and the correction method are feasible and effective.

An improved spurline structure with two rejection bands is presented in this paper, which consists of asymmetrical spurline resonators and embedded directly into microstrip line. Asymmetrical spurline resonators provide dual-bandgap characteristics and slow-wave effect. Furthermore, asymmetrical spurline structure with dual rejection bands is proposed to reduce the higher harmonics of microwave power amplifiers. To evaluate the effect of asymmetrical spurline resonators on microwave amplifiers, two InGaP HBT power amplifiers were designed and fabricated. One of them has asymmetrical spurline structure at the output section, while the other has a conventional 50-Omega microstrip line only. Results show that asymmetrical spurline structure suppresses the second and third harmonics more than 27 dB at the output and yields improved power added efficiency (PAE) and output power by 6-8% and 1-4%, respectively.