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As a common threat to the public safety, gas explosion and its damage on structures have drawn more and more attention in the academic fields. In this paper, a series of numerical simulations are conducted to study the behavior of autoclaved aerated concrete block infilled walls under gas explosion loading. Firstly, considering the difference between the blocks and the mortar, a refined numerical model is established, and the constitutive model of Brittle Damage in LS-DYNA is hired to describe the material behaviours of both materials. Based on the laboratory material test data, the parameter of the material model are selected reasonably. Then, massive numerical calculation is carried out and the dynamic response of autoclaved aerated concrete block infilled walls is captured and discussed. At last, the anti-blast ability of block infilled walls is compared with that of clay infilled wall of the same thickness. It is found that the anti-blast ability of block infilled walls is weaker than the clay infilled walls for the difference of material density and boundary conditions.

To promote engineering application of municipal sludge pyrolysis technology and reduce economic cost of sludge pyrolysis operation, the paper discussed the feasibility of sludge-based char application in three aspects: sewage adsorbent, fuel and soil improving agent. Conclusion: the sludge-based char on SCOD adsorption time in the 30min reaches saturation, the SCOD removal rate above 30%; the removal rate of sludge-carbon on A/O reactor effluent COD have less effect, but there are certain effect on nitrogen removal; the sludge-based char can be burned at 400°C, release a lot of heat, it can be used as a low-grade fuel; the sludge-based char can promote plants growth, and has a good safety performance, may be used as a good soil improving agent.

With assistance of copper ions diamond-like carbon (DLC) films were deposited on Cu substrate by liquid-phase electrochemical deposition method from a mixture of ethanol as carbon source and deionized water containing K2CO3 as electrolytic. The electrode process was analyzed and the morphology, composition and structure of the films were studied by scanning electron microscopy (SEM) and Raman spectroscopy respectively. The results show that: on the condition of 40V and 7mm between the electrodes DLC films were deposited by adding K2CO3. With assistance of copper ions the electrode reaction was promoted, the deposition rate was improved. SEM shows that the DLC film deposited with copper ions assisting is comprised of uniformly distributed particles. And the Raman spectrum shows that the G band position moves to lower wavenumber and the ratio ID/IG decreases which indicate that there is more sp3 content in the film.

Production rhythm speeding up, requiring the on-machine measurement quick and accurate, however, the measurement speed is increased along with the increase of dynamic error, so the study of dynamic error about on-machine measurement system is particularly important. This paper introduced Bayesian network to the study of dynamic error modeling about on-machine measurement system, effectively expressed the relationship between the error sources and the dynamic error, and verified the feasibility of this method.

Studying how to distribute the sampling points on processing surface has important practical significance on improving the detection quality and efficiency. So, this paper introduced Bayesian networks to the research of sampling points reasonable distribution, carried out Bayesian networks classifier learning of four typical sampling methods and the result obtained through analysis experimental and simulation data verify the feasibility of this method.

The measurement error contains many errors in NC machine tools processing and those errors will be mapped to workpiece at certain regularity. The control of error caused by cutting parameters during the precision and ultra precision process is one of the key technologies in NC machine tools processing. This article introduces Bayesian networks into the dynamic error separation modeling, with the learning process of Bayesian network structure and establishes the error separation model based on Bayesian networks, then carries out the comparison and analysis between simulate and experimental data to verify the feasibility of the method.

Two new microporous polyoxomolybdates of (NH4)2[γ-Mo8O26] (Compound I) and (NH4)2[Mo4O13] (Compound II) were synthesized hydrothermally and characterized by elemental analysis, infra-red, TG analysis and single-crystal X-ray diffraction. In the synthesis process, we found that both organic template and transition metal salt play crucial roles in the formation of crystals. Cyclic voltammetry was used to study their electrochemical properties. The results reveal that the two compounds possess electrochemical activity in 0.2M H2SO4+Na2SO4 ( pH=1 ) solution and three multi-electron transferred redox reaction (I-I´, II-II´ and III-III´) processes were obtained. The first two redox reactions (I-I´, II-II´) are reversible reaction processes but another one (III-III´) is not. The electrochemical properties of the two compounds indicate their great potential applications in electroanalysis and electrocatalysis.