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Flame-retardant reed inorganic particleboard was prepared by hot-pressing with reed particles as a reinforcing material and using magnesite cement as an inorganic adhesive. The effects of inorganic sizing amount, density, and hot-pressing temperature and time on the properties of reed inorganic particleboard were investigated by orthogonal testing. Particleboard properties were tested and characterized by means of a universal mechanical testing machine, scanning electronic microscopy (SEM), X-ray diffraction (XRD), and cone calorimetry. The results showed that the mechanical properties of particleboard prepared under conditions of 60 percent sizing capacity, 100[degrees]C hot-pressing temperature, 15 minutes hot-pressing time, and 1.2 g/[cm.sup.3] density were the best, reaching the national standard for cement particleboard. At 60 percent sizing, the characteristic peak value of inorganic adhesive hydrate crystal phase was the largest, the crystallization area dense and orderly, and the coating effect on shavings good; these attributes confirmed the trend of mechanical properties of reed shavings board increasing with sizing amount. Thus, the sizing amount had a significant influence on flame retardancy and smoke suppression performance of this particleboard. With an increased application amount, the heat release and total heat release rates of the particleboard and total smoke generation rate showed decreasing trends. Additionally, when the ignition time was delayed, the flame retardancy and smoke suppression performance of the particleboard was enhanced., At present, the main raw materials of particleboard are relatively common biomass materials, such as wood, bamboo, and agricultural and forestry residues (Zhang et al. 2013, Atoyebi et al. 2018, [...]

In this letter, a weighted sum-rate (WSR) maximization problem of cooperative reconfigurable intelligent surface (RIS) assisted downlink multiple-input-single-output (MISO) system is studied. A wireless communication framework that combines both fixed and mobile RISs is proposed for the first time. The optimization problem of maximizing the WSR is addressed by jointly devising the active beamforming and the dual-RIS passive beamforming in an alternating manner. Specifically, the active beamformer at the BS is solved by using the weighted minimum mean square error (WMMSE) method, while the passive beamforming of the RIS is achieved through the sequence phase-rotation (SPR) or the semi-definite relaxation (SDR) methods. Simulation result demonstrates that the proposed SPR method achieves the best performance, and outperforms several benchmark schemes. In addition, the WSR in the near-field performs better than that in the far-field.

Recent proliferation and integration of tissue-clearing methods and light-sheet fluorescence microscopy has created new opportunities to achieve mesoscale three-dimensional whole-brain connectivity mapping with exceptionally high throughput. With the rapid generation of large, high-quality imaging datasets, downstream analysis is becoming the major technical bottleneck for mesoscale connectomics. Current computational solutions are labor intensive with limited applications because of the exhaustive manual annotation and heavily customized training. Meanwhile, whole-brain data analysis always requires combining multiple packages and secondary development by users. To address these challenges, we developed D-LMBmap, an end-to-end package providing an integrated workflow containing three modules based on deep-learning algorithms for whole-brain connectivity mapping: axon segmentation, brain region segmentation and whole-brain registration. D-LMBmap does not require manual annotation for axon segmentation and achieves quantitative analysis of whole-brain projectome in a single workflow with superior accuracy for multiple cell types in all of the modalities tested.

•Household settings related to a higher asymptomatic SARS-CoV-2 transmission risk•Lower transmission potential for asymptomatic than (pre)symptomatic infections•Asymptomatic transmission rate lower in China than other countries included

A high-temperature and high-pressure dual-capillary viscometer was developed to measure the dynamic viscosity of liquid and supercritical coal-based kerosene in the temperature range of 299.6–678.8 K and pressure range of 0.3–40.4 MPa. The extended relative uncertainty of the measurement results ranged from 0.8–5% (confidence factor k= 2). Using the differential of the pressure drop across the capillary with flow rate in the viscosity derivation, rather than the pressure drop directly, gave better experimental precision. The measurement accuracy was validated using cyclohexane and toluene as standard fluids; the absolute average deviations (AADs) were 1.7% for cyclohexane at 0.3–20.0 MPa and 321.8–576.6 K and 2.0% for toluene at 0.3–40.6 MPa and 285.3–315.8 K. The effects of temperature and pressure on the viscosity of coal-based kerosene were investigated using four parameters: isobaric viscosity change rate, viscosity-temperature coefficient, isothermal viscosity change rate, and viscosity-pressure coefficient. It was found that the viscosity-temperature coefficient curves of coal-based kerosene intersect each other at different pressures, which are of great significance for the establishment of viscosity predictive models. Based on the characteristics of the kerosene η–Tcurve, we proposed a new modified Arrhenius–Andrade model and introduce the pressure term into the model. Compared with the modified VFT model and 10-parameter nonlinear surface model, the modified Arrhenius–Andrade model best fitted the experimental data with AAD of 1.6%.

Exploring a simple, on-demanding method of manipulating ionic conduction of ionic liquids with large amplitudes is a challenging task. Here, a reversible ion-conducting switch was obtained based on photoswitchable sol–gel transitions. The device was successfully applied in an electronic circuit to switch it on/off. The ion gel was prepared by directly mixing following individual components: azobenzene (Azo), poly(N-isopropylacrylamide) (PNIPAm), and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C2mim][NTf2]). The mixture is denoted as Azo/PNIPAm/[C2mim][NTf2]. The framework of this gel structure was particularly designed as an analogue to the physical mode of control theory: sensor/amplification/action. Light-induced isomerization of Azo acts as the light sensor to trigger the macroscopic sol–gel transition of PNIPAm assemblies. Such transition works as the amplification, which significantly affects the ionic movements, resulting in high-amplitude switching behavior. A photoswitchable ionic conductive device was demonstrated as action in this paper. Under UV irradiation, the sol-like state of Azo/PNIPAm/[C2mim][NTf2] provided a higher ion conduction (around 1 mS/cm) while being exposed to visible light, and a lower ion conduction (0.04 mS/cm) was observed in the gel state. This photoswitchable ion conductivity device was integrated to a well-designed logic gate to switch circuits on or off. This confirms the possible practical application of the sol–gel device, which outputs stable and detectable electrical signals. The research here demonstrates a simple but effective strategy to control the ionic movements, which can be applied in optoelectronic devices. The principle can be used to design different types of molecular optoelectronic switches.

Photomoieties are generally covalently attached to thermoresponsive polymers to prepare photo/thermoresponsive materials, but the bonded thermo- and photomoieties prevent us from obtaining insights into the effect of the individual response. To clarify the synergetic effect, azobenzene molecules, structurally free from poly(N-isopropylacrylamide) (PNIPAm), are utilized as photoresponsive triggers to tune upper critical solution temperature (UCST) behaviors of PNIPAm in ionic liquids (ILs). PNIPAm in an IL becomes soluble upon trans-to-cis isomerization of azobenzene under UV irradiation and aggregates again under visible light illumination. It is revealed that cis-azobenzene promotes the interaction between PNIPAm and anions but suppresses hydrogen bonding between PNIPAm chains, contributing to lower clouding temperatures under UV irradiation. Furthermore, the light-switchable macroscopic response of PNIPAm/azobenzene/IL is first exploited for an application of photoinduced reversible adhesives. This work sheds light on the intrinsic relationship between the phase transition of PNIPAm and isomerization of azobenzene in multicomponent systems.

The continuous dry co-digestion of corn straw (CS) and cow manure (CM) was studied in horizontal stainless steel push-flow reactors. The highest volumetric CH4production of 0.76L/(L·d) was obtained at the condition of total solid content (TS) = 25% with CM:CS = 1:2 (basis of TS). With the increase of TS content, the shear stress increased, which may be due to that the higher TS caused stronger interparticle flocculation. The viscosity increased with the enhance of proportion of CM, indicating that CM was more disadvantaged for the flow of materials than CS. When TS increased from 25% to 30%, CH4production sharply decreased, which could be caused by the high viscosity (30Pa·s) of the substrates, resulting in decreasing of mixing efficiency and formation of dead zones in the digester. Clostridialesand Methanosarcinawere positively correlated with TS, indicating that both are more suitable for growth in dry anaerobic digestion (AD) than other microorganisms. This study provides a theoretical basis for the application of continuous AD of agricultural and rural wastes.