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the treatment and disposal of sewage sludge is one of the hot spots in recent years, and the value of its energy utilization has gradually received attention by researchers. In this paper, the concept, yield, harm as well as the conventional disposal methods of sewage sludge are described, three kinds of main technologies of oil making from sewage sludge are introduced, including high temperature pyrolysis, low-temperature pyrolysis and direct thermo chemical liquefaction, and the research progress of these three technologies is reviewed.

Aiming at the effect of heavy metal ion on activated sludge microorganism, this paper has concluded predecessor literatures, and analyzed mechanism of action of metal ion to activated sludge microorganism and the effect to microbial growth kinetics. And it has concluded heavy metal ion effluent COD value, SV, SVI and effect of microbial community structure about activated sludge system. And then it has summarized heavy metal ion joint action on activated sludge microorganism, and some effect like pH element to heavy metal toxic actions.

The paper introduces the research status and progress of domestic and overseas researches on the effects of heavy metal ions on activated sludge microorganisms. The analysis of the research results show that the effects of heavy metals on microorganism vary with metal type, form and concentration.

Diatomite is a kind of non-metallic mineral with many pores, small density, large specific surface area, good adsorptive property, acid resistance, alkali resistance, and insulation. As a new kind of coagulant material, diatomite has characteristics of wide range of resource, good sewage treatment effect, and simple equipment for later sludge treatment, so its application prospect is broad. This paper introduced the basic conception and properties, and adsorption mechanism of diatomite, summarized the modification method of diatomite, its research and application status of water treatment, as well as its future development trends.

The viscosity of material is considered at propagating crack-tip. Under the assumption that the artificial viscosity coefficient is in inverse proportion to the power law of the plastic strain rate, an elastic-viscoplastic asymptotic analysis is carried out for moving crack-tip fields in power-hardening materials under plane-strain condition. A continuous solution is obtained containing no discontinuities. The variations of the numerical solution are discussed for mode I crack according to each parameter. It is shown that stress and strain both possess exponential singularity. The elasticity, plasticity and viscosity of material at the crack-tip only can be matched reasonably under linear-hardening condition. The tip field contains no elastic unloading zone for mode I crack.

This paper reports the development of a new jack robot. The jack robot consists of two crawler vehicles connected by 3-DOF joint mechanism which is capable of posture change, constructing a thin structure to enable it to enter narrow space, as well as high mobility in disaster sites and adaptability to irregular terrain. An electric jack mechanism and a multi-DOF manipulator are equipped in the front segment of the jack robot to accomplish jack-up operations. Adopted multiple layers screw sleeves structure, the jack mechanism can spread to the place which is almost six times the height of its own, making it possible to lift a gap up from 70 mm to 400 mm under 300 kg load driven by DC motor. With the help of the multi-DOF manipulator, precise operations to the jack mechanism can be realized. Experimental results of driving test and jack-up test validate the capability of the multi-linked tracked jack robot.

The purpose of this study was to investigate the influencing mechanism of Porphyromonas gingivalis extracellular vesicles on human periodontal ligament fibroblasts to better understand the pathogenesis of periodontitis, the major cause of adult tooth loss. Human periodontal ligament fibroblasts were cultured and randomly assigned to a control group and an extracellular vesicles (ECV) group. The ECV group was exposed to isolated Porphyromonas gingivalis extracellular vesicles; the control group was not exposed. Western blotting was used to detect expression of matrix metalloproteinase 1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1), and RT-PCR was used to detect mRNA expression of alkaline phosphatase (ALP). When human periodontal ligament fibroblasts were processed by Porphyromonas gingivalis extracellular vesicles (ECV), protein expression levels of both MMP-1 and TIMP-1 were significantly higher than that of the control group (P

This paper presents a novel exoskeleton hand system for measuring extravehicular activity spacesuit glove (EVA glove) joint's mechanical characteristics. For adapting to variety sizes of gloves, the proximal phalanx of exoskeleton finger can be adjusted through an additional four-bar transmission mechanism. The exoskeleton hand can apply forces that actuate both flexion and extension of EVA glove. Based on its special mechanical structure, a mathematic model of flexible EVA glove joint has been built.