[en] The production of conductive dust not only pollute the environment, harm people's health, but also bring great harm to the safe operation of electrical equipment. Such as shorting electrical equipment, electrical switch according to touch bad, poor ventilation, etc., it is easy to cause equipment electrical cabinets failure problems, in order to strengthen the reliability of enterprise production, for the timely and effective maintenance of the equipment failure, and take effective measures to guarantee with the safe operation of the equipment electrical cabinets in conductive dust environment. A great deal of work has been done in this paper to prevent the harm of dust to the electrical equipment and remarkable results have been obtained. (paper)

[en] The principal neural cell types forming the mature central nervous system (CNS) are now understood to be diverse. This cellular subtype diversity originates to a large extent from the specification of the earlier proliferating progenitor populations during development. Here, we review the processes governing the differentiation of a common neuroepithelial cell progenitor pool into mature neurons, astrocytes, oligodendrocytes, ependymal cells and adult stem cells. We focus on studies performed in mice and involving two distinct CNS structures: the spinal cord and the cerebral cortex. Understanding the origin, specification and developmental regulators of neural cells will ultimately impact comprehension and treatments of neurological disorders and diseases. - Highlights: • Similar mechanisms regulate cell fate in different CNS cell types and structures. • Cell fate regulators operate in a spatial–temporal manner. • Different neural cell types rely on the generation of a diversity of progenitor cells. • Cell fate decision is dictated by the integration of intrinsic and extrinsic signals

[en] In this paper, we present a method to realize feature extraction on low contrast magnetic domain images of magneto-optical recording films. The method is based on the following three steps: first, Lee-filtering method is adopted to realize pre-filtering and noise reduction; this is followed by gradient feature segmentation, which separates the object area from the background area; finally the common linking method is adopted and the characteristic parameters of magnetic domain are calculated. We describe these steps with particular emphasis on the gradient feature segmentation. The results show that this method has advantages over other traditional ones for feature extraction of low contrast images

No abstract available

[en] Non-medical radiation generators are surveyed in Gansu province in aspects of application, safety and protection. Specific to the existing problems, this paper proposes two ways to deal with the environmental management problem from prospectives of both the operating management and the environmental regulatory authorities. (authors)

[en] Celaomiao basin is located on the West side of Lang Shan in the northern part of Bayannaoer city, Inner Mongolia autonomous region, and belongs to the junction of the North China plate sub-tectonic unit, the northern North China continental margin hyperplasia belt Baoyintu-Xilinhot volcanic passive continental margin and the North China block Yinshan uplift. The geochemical characteristics of river sediments show that the elements in the area are: K₂0 (concentration Clark value of 2.06), Th (concentration Clark value of 1.32), U (concentration Clark value of 0.81) and other elements. Based on the geochemical characteristics and regional Geological metallogenic background, this paper analyzes that the Celaomiao Basin (CaoHai wave) has a large uranium metallogenic prospect. (authors)

[en] Shalaxibie copper locates to the northwestern margin of north china platform, that is Bayinnuoergong fault uplift, Alashan platform, north china platform. Regional structure is complex. Northern adjacent to the fracture of the northern margin of north china platform, eastern is separated by Baoyintu fracture. The Strata outcropping include Alashan group, Zhaertaishan group and meso-cenozoic group. The Main structure line is east to north, followed by the north west or nearly ns-trending fault. The ore body in the earth's surface is not exposed, it distribute in the skarn alteration zone in the southwest area, the main ore output in the alteration of granodiorite. This paper detailed the regional background, mining area geological feature and deposit's geological feature. lt points out that Shalaxibie copper is a skarn type deposits. The skarn alteration zone between marble and granodiorite is an important prospecting criteria. (authors)

[en] Jindongzi ditch gold mine is located within the jurisdiction of Ningqiang County in Shanxi Province, is located in the Yangzi plate Kekexili-Bayankara Mesozoic orogenic belt, Bikou tectonic wedge block of Motianlin lot, located in the 'Mianluening' into mining area in the southwest. Strong volcanic hydrothermal activity and the ductile shear action in the Mining area, provides the material foundation and good tectonic environment for The formation of gold mine. This paper analyzes the regional geological background and geological background, Deem the mining area has great gold prospecting foreground. (authors)

[en] Graphical abstract: A composite separator based on plasma-treated fluorinated polypropylene (PP) nonwoven, poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) and SiO_2 nanoparticles exhibiting enhanced thermal stability, ionic conductivity and electrochemical properties. Display Omitted -- Highlights: •Fluorinated segments are introduced on the surface of PP nonwoven through plasma treatment. •The obtained composite separators exhibit better physical and electrochemical properties. •The capacity of half-cell with composite separator keeps above 150 mA h g"−"1 after 100 charge–discharge cycles. -- Abstract: Separators have drawn substantial attention because of their important role in achieving the safety and good electrochemical performance of lithium-ion batteries. In this study, we report a new type of composite membrane prepared by a combination of fluorinated polypropylene (PP) nonwoven fabric, poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) and SiO_2 nanoparticles. 2, 2, 3, 3, 4, 4, 5, 5-Octafluoropentyl methacrylate (OFPMA) is first grafted on the surface of PP nonwoven by plasma treatment to improve the nonwoven’s adhesion with PVdF-HFP. Two kinds of composite separators have been prepared by using the different PP nonwovens together with PVdF-HFP and SiO_2 nanoparticles. They were separately designated as PHS for commercially raw PP nonwoven system and PHS-n for OFPMA-modified PP nonwoven systems (n means plasma treatment time). The morphology, electrolyte uptake, ionic conductivity and electrochemical properties of the composite separators have been analyzed by scanning electron microscope (SEM) analysis, impedance measurement, charge-discharge cycle and C-rate tests, respectively. The results indicate that PHS-10 composite separator using the modified PP nonwoven treated by plasma for 10 min exhibits much better properties than PHS separator, including an improved mechanical property, thermal stability, electrolyte uptake (290 wt%) and ionic conductivity (1.76 mS cm"−"1). More importantly, the LiFePO_4/Li half-cell assembled with PHS-10 composite separator displays a good C-rate performance, which shows an enhancement in the chemical stability and discharge capacity. The capacity keeps above 150 mA h g"−"1 after 100 charge–discharge cycles. These performances endow this composite membrane as a promising candidate for high-performance lithium-ion battery separators

[en] An electrically permeable elliptical nano-hole or nano-crack embedded in an infinite piezoelectric material with surface effect is investigated based on the Gurtin–Murdoch surface/interface model, which is subjected to far-field anti-plane mechanical and in-plane electrical loads. The electric field inside the elliptical nano-hole has been taken into consideration, and exact electroelastic fields near the elliptical nano-hole are obtained by using the technique of conformal mapping. The size-dependent stress and electric displacement intensity factors at the crack tip are derived exactly for both electrically permeable and impermeable boundary conditions when the elliptical nano-hole reduces to the nano-crack. Numerical examples are illustrated to show the surface effects on the stress and electric displacement intensity factors of electrically permeable and impermeable cracks, and on the stress and electric field concentrations around the electrically permeable and impermeable holes. The results indicate that the size dependence of an electrically permeable nano-hole or nano-crack is entirely different from that of the electrically impermeable case.