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Under the background of the increasing demand for germanium in high-tech, this paper finds out the mechanism of silicon germanium polymerization precipitation by simulating the leaching process of zinc oxide dust containing germanium. By comparing and analyzing the simulation experiments under ultrasonic and conventional conditions, the mechanism of efficient dispersion and depolymerization of germanium silicon precipitation induced by ultrasonic was found out. The results show that in the leaching process of germanium-containing zinc oxide dust, due to the increase of local pH, some silicon ions in the solution will hydrolyze and polymerize to form silicic acid colloid to adsorb germanium in the solution, causing the loss of germanium 14.81%, resulting in low recovery rate of germanium industry. Ultrasonic wave was introduced in the leaching process, and the shock wave and micro-jet released by ultrasonic cavitation continuously impacted the surface of polysilicate colloid. The germanium adsorbed on the surface of the silicic acid colloid is desorbed, and the large particles of silica gel are depolymerized into small particles of silicic acid, which reduces the adsorption of silica gel on germanium. The loss of germanium under ultrasonic conditions can be reduced by 59.35%. This study can effectively realize the efficient recovery of germanium in zinc oxide dust, and provide process and theoretical basis for the sustainable development of germanium industry. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports detailed investigation on the influence of microwave irradiation on the cobalt oxalate (Co(C2O4)·2H2O):cobalt oxide (Co3O4) systems in different mass ratio. The analyses of the spectra attenuation and relative frequency shift showed that Co(C2O4)·2H2O had weak capability to absorb microwave irradiation, while Co3O4 had good capability to absorb microwave irradiation. The ability to absorb microwave irradiation was also assessed based on the temperature raise of the system exposed to microwave irradiation. The capability to absorb microwave irradiation of Co(C2O4)·2H2O increased with an increase of ratio Co3O4 in system. [Copyright &y& Elsevier]

Abstract: Woodceramics samples derived from carbonized tobacco stems and different contents of phenolic resin, using different carbonization temperatures have been investigated by Raman spectroscopy. It was found that the full width at half maximum (FWHM) and the R-value decreased with an increase of the carbonization temperature and the content of phenolic resin. And the crystallite size L a of these samples show low microcrystalline size, i.e. L a varying between 1.85 and 5.40nm. The results obtained indicate that 973K is the turning point temperature for the preparation of woodceramics. The results of Raman spectra were confirmed by SEM results of the woodceramics. [Copyright &y& Elsevier]

Abstract: In this paper, activated carbons with high surface area from carbonized tobacco stems with K2CO3 activation by microwave radiation were investigated. Effects of microwave radiation time and K2CO3/C ratio on the yield and adsorption capacities of activated carbons were evaluated. Experimental results indicated that the optimum conditions were as follow: microwave power 700W; microwave radiation time 30min; K2CO3/C ratio 1.5:1. Iodine number, amount of methylene blue adsorption and the yield of activated carbon prepared under optimum conditions were 1834mg/g, 517.5mg/g and 16.65%, respectively. Surface area, micropore volume and pore size distribution (PSD) of the carbons were determined by the BET, H-K and DFT methods. Results showed that activated carbons had a micropore content about 59.98% and a small number of mesopores and macropores; BET specific surface area and total pore volume were 2557m2/g and 1.647cm3/g, respectively. [Copyright &y& Elsevier]

Background Nicotine craving and relapse often occurs after reactivation of nicotine reward memories. We recently developed a memory retrieval–reconsolidation interference procedure in which reactivating nicotine reward memories by acute exposure to nicotine (the unconditioned stimulus [UCS]) and then pharmacologically interfering with memory reconsolidation decreased relapse to nicotine seeking in rats and nicotine craving in smokers. Here, we investigated underlying mechanisms. Methods In the first series of experiments, we trained rats for nicotine-induced conditioned place preference (CPP) or nicotine self-administration and ventricularly microinjected them with the protein synthesis inhibitor anisomycin immediately after UCS-induced memory retrieval. In the second series of experiments, we used tyramide-amplified immunohistochemistry–fluorescence in situ hybridization to examine neural ensembles in the basolateral amygdala (BLA) reactivated by nicotine conditioned stimulus– or UCS-induced memory retrieval. We then used the Daun02 chemogenetic inactivation procedure to selectively inhibit the nicotine UCS-reactivated BLA neuronal ensembles. Results Ventricular injections of the anisomycin immediately after nicotine UCS memory retrieval inhibited subsequent nicotine CPP and relapse to operant nicotine seeking after short or prolonged abstinence. More important, within BLA, distinct neuronal ensembles encoded pavlovian CPP and operant self-administration reward memories and nicotine (the UCS) injections in the home cage reactivated both neuronal ensembles. Daun02 chemogenetic inactivation of the nicotine-reactivated ensembles inhibited both nicotine CPP and relapse to nicotine seeking. Conclusions Results demonstrate that the nicotine UCS-induced memory retrieval manipulation reactivates multiple nicotine reward memories that are encoded by distinct BLA neuronal ensembles that play a role in nicotine preference and relapse. [ABSTRACT FROM AUTHOR]

In this paper, a security enhancement for double random phase encoding (DRPE) by introducing a rear-mounted phase masking procedure is presented. Based on exhaustively studying the cryptanalysis achievements of DRPE and its variants, invalidation of the second lens, which plays a critical role in cryptanalyzing processes, is concluded. The improved system can exploit the security potential of the second lens and consequently strengthen the security of DRPE. Experimental results and security analyses are presented in detail to demonstrate the security potential of the proposed cryptosystem. [ABSTRACT FROM AUTHOR]

The simulation of bubbling fluidized beds (BFB) residence time distribution (RTD) based on the structure-based drag model are conducted for the single and binary gas-solid phases systems, a comparison of computed results with experimental data proves that our model is applicable to both systems with better accuracy. The revised drag coefficient ( H d ) increases with decreasing the gas velocity or increasing the particle diameter. The increase of the feed rate could improve the solids flow pattern to be close to the plug flow, while increasing gas velocity or bed height would lead to a wider RTD. The particles in the binary mixture are in more diffusion-oriented movement so as to have less MRT (mean residence time) than that of the single system. The coarse particles with longer MRT are simulated to accumulate into the bed bottom with a slower vertical velocity. [ABSTRACT FROM AUTHOR]

This paper presents an information authentication scheme using sparse representation of double random phase encoding in fractional Fourier transform domain. Different from traditional cryptographic applications, only sparse version of the ciphertext is available at the receiver end. The decrypted image is unrecognizable and of no meaningful information of the plaintext, which can enhance the resistance against various attacks. The decrypted image can be authenticated using nonlinear optical correlation approach. Numerical simulations have been carried out, and the results prove the effectiveness and noise resistance of the proposed scheme. [ABSTRACT FROM AUTHOR]

Aiming to comprehensively improve the safety of energetic materials by minimizing their sensitivity to external stimuli such as impact, friction, static electricity and heat, a bionic functional layer strategy is developed to construct energetic composites with core-shell-shell structure. The morphology and structure of the samples were characterized in depth by scanning electron microscopy (SEM), X-ray diffractometer (XRD) and X-ray photoelectron spectra (XPS). The results show that the bionic functional layer forms a dense and complete shell layer on the surface of energetic material, the two-dimensional (2D) material is uniformly and tightly coated on the surface of energetic material based on the super adhesion of the functional interface layer, and the core-shell-shell structure CL-20@Polydopamine@Graphene Oxide (CL-20@PDA@GO) is successfully prepared. The preparation process does not cause the crystalline transformation of energetic material. In addition, the impact sensitivity, friction sensitivity, electrostatic accumulation characteristics and thermal properties of the samples were also evaluated. The results indicate that the bionic functional layer and 2D material can synergistically reduce the sensitivity of energetic material to external stimuli based on their intrinsically superior properties. Therefore, synergistic effect of bionic functional layer strategy in this work has the potential to be extended for multiple properties regulation of energetic materials. • Bionic functional layer-based strategy for constructing core-shell-shell structural composites. • A dense and complete PDA shell layer is uniformly encapsulated on the CL-20 surface. • The bionic functional layer enhances the interfacial interaction between the 2D materials and the energetic materials. • The synergistic effect of functional interface layers and 2D materials reduces the sensitivity of energetic materials. [ABSTRACT FROM AUTHOR]

The effects of process conditions on preparation of U 3 O 8 by calcination from ammonium uranyl carbonate in microwave fields were assessed and optimized for maximizing the total uranium as well as calcination temperature, adopting as Central Composite Design (CCD) methodology. The process variables assessed were calcination temperature, calcination duration and mass of sample. A quadratic model relating the process variables and the total amount of uranium and U 3 O 8 was proposed eliminating the insignificant parameters. The optimal calcination conditions were estimated to be a calcination temperature of 942.75 K, calcination duration of 8.78 min, with the corresponding total uranium and U 3 O 8 to be 82.07% and 31.33%, respectively. [ABSTRACT FROM AUTHOR]

Optical information security systems have drawn long-term concerns. In this paper, an optical information authentication approach using gyrator transform based double random phase encoding with sparse representation is proposed. Different from traditional optical encryption schemes, only sparse version of the ciphertext is preserved, and hence the decrypted result is completely unrecognizable and shows no similarity to the plaintext. However, we demonstrate that the noise-like decipher result can be effectively authenticated by means of optical correlation approach. Simulations prove that the proposed method is feasible and effective, and can provide additional protection for optical security systems. [ABSTRACT FROM AUTHOR]

Crofton weed was converted into a high-quality activated carbon (CWAC) via microwave-induced CO2 physical activation. The operational variables including activation temperature, activation duration and CO2 flow rate on the adsorption capability and activated carbon yield were identified. Additionally the surface characteristics of CWAC were characterized by nitrogen adsorption isotherms, FTIR and SEM. The operating variables were optimized utilizing the response surface methodology and were identified to be an activation temperature of 980 °C, an activation duration of 90 min and a CO2 flow rate of 300 ml/min with a iodine adsorption capacity of 972 mg/g and yield of 18.03%. The key parameters that characterize quality of the porous carbon such as the BET surface area, total pore volume and average pore diameter were estimated to be 1036m²/g, 0.71 ml/g and 2.75 nm, respectively. The findings strongly support the feasibility of microwave heating for preparation of high surface area porous carbon from Crofton weed via CO2 activation. [ABSTRACT FROM AUTHOR]