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With the conventional gas or water atomization process of synthesizing metallic powders, it is difficult to obtain graphite structure in a gray cast powder particle because of rapid cooling of the molten droplets. In this work, a fabrication method of gray cast iron powder with graphite structure was proposed based on a structural transplantation route. In the fabrication process, the precursor powder was firstly prepared by mechanically separating from as-cast gray cast iron bulk, then the precursor powder was ball-milled with different ratios of ball-to-powder to obtain final powders. The profile, size distribution, and surface roughness of final powders were quantitatively characterized by circularity, particle uniformity level, and fractal dimension method, respectively. It was found that ball milling smoothed the sharp edges and corners of the precursor powder and reduced the size of the precursor powder. As a result, the ball-milled powders have a more regular shape, more uniform size distribution, lower surface roughness, and better flowability than the precursor powder for thermal spray applications. [ABSTRACT FROM AUTHOR]

Paratylenchus chongqingensis n. sp. extracted from the soil associated with Ophiopogon japonicus in China is described and illustrated. The new species is characterized by having the female with a body length of 243–274.5 μm, stylet 21–24.5 μm long, lip region distinctly set off forming a flattened labial disc, lateral field with three lines, lateral vulval flaps distinct, tail with a beak-like and subacute terminus; male with a 224.5–246.5 μm long body, spicules 13–14.5 μm long, stylet lacking and pharynx degenerate, tail tapering gradually, and then becoming narrow abruptly near the terminus, forming a short pointed filiform tail tip. The internal transcribed spacer sequences of the ribosomal RNA (ITS rRNA) gene of the new species were amplified and sequenced. The phylogenetic relationships of this new species with other Paratylenchus spp. using the ITS rRNA gene is given in this study. [ABSTRACT FROM AUTHOR]

Isotactic polypropylene/poly( l-lactide) blends were toughened by blending polyethylene-glycidyl methacrylate (EGMA) as compatibilizer and dicumyl peroxide (DCP) as compatibilization accelerator. Isotactic polypropylene (iPP)/poly( l-lactide) (PLLA)/EGMA/DCP blends showed remarkably improved impact toughness and excellent flexibility, moderate levels of strength, and modulus. Reactive compatibilization between iPP and EGMA as well as PLLA and EGMA was studied using Fourier transform infrared spectroscopy. The 'salami'-like phase structure of the dispersed domains in the iPP/PLLA/EGMA ternary blends was observed. With the further addition of DCP, the EGMA phase evolved from occluded sub-inclusions into an interface boundary. The significant increase in impact strength of iPP/PLLA/EGMA/DCP blends was ascribed to the effective interfacial compatibilization. This study provides a new route to prepare a cost-effective material with partial biodegradability, good impact toughness, and tensile strength. Meanwhile, a deep insight into the optimization of properties of multicomponent blends by morphology transition was proposed. [ABSTRACT FROM AUTHOR]

A new plant nematode species named Paratylenchus guangzhouensis n. sp. was extracted from the soil associated with Bambusa multiplex in Guangzhou, Guangdong Province, China. The new species is characterized by having the female with a small body 217-247 μm long, a slender stylet 43-49.5 μm long, head rounded without distinct submedian lobes, amphid openings large, and bow-tie like in shape, oral opening with two prominent ridges laterally, lateral field with three distinct lines, small lateral vulval flaps and tail tip finely rounded to bluntly rounded; male with a 237.5 μm long body, spicules 15.5 μm long, stylet lacking and pharynx degenerate; and the fourth-stage juvenile with a stylet. The internal transcribed spacer sequences of ribosomal RNA (ITS rRNA) gene of the new species were amplified and sequenced, and a phylogenetic tree inferred from the ITS rRNA gene is given in this study. [ABSTRACT FROM AUTHOR]

A new plant nematode species, Hemicaloosia guangzhouensis n. sp., collected from the soil associated with Schima superba in a forest park in Guangzhou, China is described. The new species is characterized by having a female with a slender body, 798-961 μm in length, stylet 59-69 μm long, tail 115-145 μm long, a membranous sheath closely adpressed to the entire body, lateral fields marked by one longitudinal line with breaks and anastomoses of transverse striae, total number of annuli 282-313, two lip annuli both projecting slightly anterior, excretory pore 51-58 annuli from anterior end, the number of annulus between vulva and anus 7-11, the number of annulus from vulva to tail terminus 58-69, spermatheca empty; and male unknown. The internal transcribed spacer of ribosomal RNA (ITS rRNA) gene, D2-D3 region of 28S ribosomal RNA (28S rRNA) gene, partial 18S ribosomal RNA (18S rRNA) gene of the new species were amplified and sequenced. The 50 % majority rule consensus trees inferred from ITS rRNA, 28S rRNA, partial 18S rRNA gene sequences of H. guangzhouensis n. sp. and some other species in the suborder Criconematina are also presented in this study. PCR-ITS-RFLP diagnostic profile generated by six restriction enzymes for H. guangzhouensis n. sp. is given. [ABSTRACT FROM AUTHOR]

The morphology and mechanical properties of poly(ethylene-octene) copolymers (POE) obtained by dynamic packing injection molding were investigated by mechanical tests, differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The mechanical tests found that only POE with low octene content and high molecular weight show apparent response for external shear field. Further investigation has been done by DSC, FT-IR, and SEM in order to make clear the reason of that phenomenon. Finally, the hypothetical mechanism of POE microstructure formation under shear field has been proposed. For POE with low octene content and high molecular weight, orientation degree and mechanical properties both increase substantially under shear field. For POE with low octene content and low molecular weight, orientation degree and crystallinity increase under shear field, but it is not dramatically benefit for the mechanical properties. For POE with high octene content and high molecular weight, the shear field has little effect on the morphology and mechanical properties. [ABSTRACT FROM AUTHOR]

The effects of nucleating duality, imposed by a mixed nucleating agent (NA) system containing multi-walled carbon nanotubes (MWCNTs) and a rare earth (WBG), on the crystallization behaviors of isotactic polypropylene (iPP) including the peak temperature of crystallization ( T), polymorphic composition, and crystalline morphology, were probed in detail by calorimetry, X-ray diffraction, and polarized light microscopy. In such mixed nucleating agent system, MWCNTs is active filler to induce α-nucleation for iPP, while WBG serves as β-nucleating agent. When the WBG content was low (0.05%), the crystals of WBG were as a form of individual isotropic dendrite, and the enhancement of T was achieved by the incorporation of MWCNTs. As the WBG content was high as 0.1%, a percolated NA network consisted of needlelike crystals of WBG yielded before nucleating the prevalent crystallization of iPP. In this case, the addition of MWCNTs has no obvious effect on T. However, by varying the mass proportion of MWCNTs/WBG, the polymorphic composition was adjusted significantly, indicating a nucleation competition between MWCNTs and WBG. Although the competitive growth existed between α-crystals nucleated by MWCNTs and β-crystals nucleated by WBG, the formation of primary β-crystallite was always prior to the α-nucleated crystallization, as confirmed by crystalline morphology. These findings are useful for developing a new pathway to prepare iPP-based composite with good mechanical property via the addition of mixed nucleating system containing active inorganic filler and β-nucleating agent. [ABSTRACT FROM AUTHOR]

The phase morphology and thermal behavior of various isotactic polypropylene (PP)/linear low density polyethylene (LLDPE) blends were investigated with aid of scanning electron microscopy (SEM) and differential scanning calorimetry (DSC), respectively. The effect of barrel (melt) temperature on the morphology, thermal behavior and the resultant mechanical properties of the injection molded bars was the research focus, and the influence of LLDPE composition was also taken into account. It was found that the mechanical properties, especially the tensile ductility and the impact strength, were greatly affected by the processing temperature. The samples obtained at low temperatures had the highest elongation at break and impact strength, while those molded at high temperatures had the poorest toughness. Two reasons were responsible for that: first, the phase size in the samples increased with the processing temperature; second, possible orientation existed in the samples obtained at low processing temperatures. [ABSTRACT FROM AUTHOR]

Hipposideros pratti is mainly distributed in mainland China. Many geographical barriers, which might cause different populations of H. pratti to appear differentiation, exist in its distribution areas. Whether the differentiation having reached the levels for subspecies classification requires further study. Currently, there is not a comprehensive study for the external measurements and molecular sequences of H. pratti . The taxonomic status of H. pratti subspecies remains uncertain. To explore the differences and taxonomic status of H. pratti , we conducted a series of surveys on bats in four different areas of China from 2012 to 2015. We performed multivariate morphometric analyses using 16 external and 25 skull measurements and analysed sequence data of two mitochondrial genes (Cytb and COI). Scatter plots indicated that both external and cranial measurements of samples from the four geographical regions separated into two groups: specimens from Western mountain and plateau subregion in Central China (CW) and Southwest mountainous subregion in Southwest China (WS) gathered into a CW-WS group, and specimens from Eastern hilly and plain subregion in Central China (CE) and Min-Guang coastal subregion in Southern China (SM) gathered into a CE-SM group. The divergence between the CW-WS and CE-SM groups for the Cytb and COI genes were 1.6–2.4% and 1.9–2.3%, respectively, which reached the levels required for identifying subspecies classification according to previous studies. Moreover, in the phylogenetic tree based on Cytb and COI sequences, specimens from the regions CW and WS formed a clade, and specimens from the regions CE and SM formed another clade. Both the morphological and molecular results support the conclusion that H. pratti from the CW-WS group represents H. p. pratti , and the CE-SM populations should be termed H. p. sinicus . [ABSTRACT FROM AUTHOR]