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By injecting cryogenic deuterium pellets into H-mode plasmas with edge localized modes (ELMs) from the low-field side (LFS) on EAST tokamak, the impact of these pellets on the edge plasma can be investigated. In some cases of pellet injection (PI), the intermediate phase (I-phase), i.e, the dithering-like cycles, have been observed. Experiments show that during one dithering-like cycle, three phases can be distinguished, which are closely related to the variations in the pedestal density profiles and density gradient after PI. Phase 1 is characterized by rapid particle loss and a density pedestal crash, phase 2 has a relatively low density gradient and enhanced edge density fluctuation and phase 3 corresponds to the relatively fast recovery of the density pedestal and reduced edge density fluctuation. Through an experimental analysis, it is shown that the plasma will enter the I-phase when the edge line-averaged density increases beyond a certain threshold value after PI. H-I-H transitions are more likely to be observed when the edge line-averaged density is greater than the core line-averaged density. [ABSTRACT FROM AUTHOR]

Highlights • Exchange bias is observed in films deposited with P O2 ≤ 20 mTorr. • Coercive field enhanced about one order for samples deposited at low P O2. • Ferromagnetic properties of LMO films deposited on different substrates are studied. • A maximum coercive field and the existence of exchange bias for 20 nm-thick LMO/STO samples. Abstract We systematically investigated the ferromagnetic properties of LaMnO 3 (LMO) films grown on SrTiO 3 (STO) substrates with varying deposition oxygen pressure P O 2 (0.2 ≤ P O 2 ≤ 200 mTorr). It was found that the films only deposited with P O2 ≤ 20 mTorr showed exchange bias behavior and meantime the coercive field H C of LMO films deposited below 20 mTorr is about one order of magnitude larger than that of films deposited at 200 mTorr. When the LMO films were deposited at 20 mTorr on different substrates [LaAlO 3 (LAO), (LaAlO 3) 0.3 (Sr 2 AlTaO 6) 0.7 (LAST), SrTiO 3 (STO) and KTaO 3 ], LMO/STO sample showed the maximum H C , even though all of them exhibit exchange bias behavior. Thickness dependence of magnetic properties in LMO/STO films deposited at 20 mTorr indicated a maximum coercive field and the existence of exchange bias for 20 nm-thick LMO sample. Based on our results, the enhancement of coercive field and exchange bias was attributed to the competition between different magnetic phases induced by oxygen vacancies and Jahn-Teller effect from strain-induced orbital ordering. [ABSTRACT FROM AUTHOR]

Atomically-flat thin films of ferrimagnetic insulator Tb 3 Fe 5 O 12 (TbIG) were grown on (1 1 1)-oriented Gd 3 Ga 5 O 12 (GGG) substrates by pulsed laser deposition. Magnetic measurements indicated the easy magnetic axis of TbIG film was out-of-plane, as a result of the substrate-induced compressive in-plane strain within the film. The temperature dependence of anomalous Hall effect (AHE) in Pt/TbIG bilayer was systematically studied with the applied magnetic field normal to the film plane, with square hysteresis AHE loops being observed. Reversal of AHE sign occurred twice between 10 K and room temperature, one at 50 K and another around 220 K, the latter of which was accompanied by complex magnetization switching behavior. The peculiar behavior of AHE loop around 220 K is closely related to the compensation point of TbIG. On the other hand, the sign change at 50 K was attributed to the modification of Pt electronic structure by TbIG. Our results highlight the relation between the AHE of Pt and magnetic properties of TbIG, which can be used for probing the magnetism in TbIG. [ABSTRACT FROM AUTHOR]

Highlights • Optimization model for LHS with unsteady inlet temperature was proposed. • Performance optimizations of multistage LHS unit were performed. • Expressions of optimum PCM melting temperatures were derived. • Effects of geometric parameters were investigated. • Results are significant for PCMs selection. Abstract An optimization model for a multistage latent heat storage (LHS) unit with unsteady heat transfer fluid (HTF) inlet temperature was proposed. Thermodynamic analysis and optimization were performed based on the entransy theory. The expressions of the optimum phase change material (PCM) melting temperatures ( T m,opt ) were derived. The effects of geometric parameters and unsteady HTF inlet temperature on the optimum phase change temperatures were investigated. The results indicate that with the increase of stage number ( n ), T m1,opt increases and T mn,opt decreases, which is beneficial to extend the selection range of PCM. For fixed entransy dissipation condition, increasing n will not change the fluctuation of the HTF outlet temperature; however a nearly uniform HTF outlet temperature can be obtained by increasing unit length ( L ). The unsteady HTF inlet temperature has great effects on the optimum phase change temperature. For a 3-stage LHS unit, the optimum phase change temperature of each stage increases by 14.9 K, 26.4 K and 38.0 K respectively with respect to the values obtained by steady method, which causes the heat storage capacity decreases by 6.1% and entransy dissipation decreases by 10.6%. The present work can provide guidance for the design of the multistage LHS unit with unsteady HTF inlet temperature. [ABSTRACT FROM AUTHOR]

Because of the increasing market potential of Pacific white shrimp ( Litopenaeus vannamei) and limited availability of coastal areas for production, culture of L. vannamei at low salinity is a growing trend throughout the world. Dietary manipulation could improve the growth performance of L. vannamei at low salinity. This study reared L. vannamei with glucose, sucrose and corn starch as dietary carbohydrate sources, respectively, at a low salinity. The results indicated that the sucrose and glucose feeding groups showed better growth performance. An Illumina-based sequencing method was used to examine the intestinal bacterial composition and the results indicated that Proteobacteria were the most prevalent members, but abundance of Actinobacteria decreased while Firmicutes increased in the corn starch-fed group. Furthermore, bacteria related to complex carbohydrate degradation were in lower abundance, whereas the abundance of opportunistic pathogenic bacteria increased in corn starch-fed group than the other two groups, suggesting that the diet imposes selective pressure on the intestinal microbiota. Complex carbohydrates were not the ideal energy sources for L. vannamei at low salinity because the host has higher energy demand in the stressful conditions while the complex carbohydrate degradation efficiency of the gut microbiota in L. vannamei is limited. [ABSTRACT FROM AUTHOR]

Thermodynamic analysis and optimization of a multistage latent heat storage (LHS) unit with unsteady heat transfer fluid (HTF) inlet temperature were performed based on the entransy theory. The expressions of the optimum phase change material (PCM) melting temperatures ( T m,opt ) were derived. The results indicate that with the increase of stage number ( n ), T m1,opt increases and T mn,opt decreases, which extends the selection range of PCM. For fixed entransy dissipation condition, increasing n will not change the fluctuation of the HTF outlet temperature; however, a nearly uniform HTF outlet temperature can be obtained by increasing unit length ( L ). The unsteady HTF inlet temperature has great effects on the optimum phase change temperature. For a 3-stage LHS unit, the optimum phase change temperature of each stage increases by 14.9 K, 26.4 K and 38.0 K respectively with respect to the values obtained by steady method, which causes the heat storage capacity decreases by 6.1% and entransy dissipation decreases by 10.6%. The greater the temperature fluctuation is, the greater the effects will be. The present work can provide guidance for the design of the multistage LHS unit with unsteady HTF inlet temperature. [ABSTRACT FROM AUTHOR]

Abstract: Methods for seeding silicon substrates with pretreatments and the in situ generation of diamond nuclei by the bias enhanced nucleation (BEN) have been studied to examine their effects on the nucleation density as well as the morphology of grown and seeded sides, the growth rate, and the quality of nanocrystalline diamond films. Pretreatments including mechanical abrasion by diamond paste, exposure of the silicon substrate to a hydrocarbon plasma, and ultrasonication of silicon in solvents with suspended nano- or micro-diamond powders were studied. With an optimized diamond seeding or nucleation process, ultra-thin, smooth and homogenous nanocrystalline diamond films can be fabricated. [Copyright &y& Elsevier]

Abstract: Gas mixtures containing up to 40% nitrogen by volume and 1% CH4 with the balance being argon have been used for the deposition of nitrogen doped nanocrystalline diamond (NCD) films by means of microwave plasma enhanced chemical vapour deposition (MPECVD). The CVD plasma was monitored by optical emission spectroscopy to reveal the plasma species, e.g., CN molecules, as a function of the nitrogen additive. Structural properties of the deposited NCD films were studied by FESEM and Raman spectroscopy. Effects of nitrogen doping on the electrical resistivity and electron field emission characteristics of the NCD films were measured. In this work, correlation between the structural and electrical properties of NCD films and the nitrogen additive to the CVD plasma will be presented and discussed. [Copyright &y& Elsevier]

Abstract: Many research groups have reported that when methane was diluted by argon for microwave plasma-enhanced chemical vapor deposition (CVD) of diamond, growth of large-grain microcrystalline diamond (MCD) was suppressed, while nanocrystalline diamond (NCD) was deposited. We report for the first time the growth of well-faceted MCD by microwave plasma CVD in argon-diluted methane without molecular hydrogen additive or with only little (2%) hydrogen additive. High-density C2 radicals generated in the plasmas might be responsible for both the promotion of secondary nucleation of diamond for the growth of NCD in atomic hydrogen deficient environments and the promotion of the growth of large-grain diamond at the presence of adequate atomic hydrogen leading to the deposition of MCD. A nonuniform plasma ball was applied to grow both MCD and MCD simultaneous on the same silicon substrate in the same gas mixture. [Copyright &y& Elsevier]

Well-faceted microcrystalline diamond (MCD) films were deposited along with nanocrystalline diamond (NCD) films on the same substrate by a microwave plasma in the gas mixture of 1% CH4+5% H2+94% Ar. This was achieved by forcing a microwave plasma ball generated at 170 torr gas pressure to touch a silicon substrate that was pre-seeded by nanocrystalline diamond powder resulting in a high concentration of atomic hydrogen on the surface of growing diamond. Previously reported compositional mapping of the argon–methane–hydrogen system for MCD and NCD growth was not valid in this process parameter space. The non-uniform concentrations of atomic hydrogen and carbon containing radicals such as C2 as well as varied local substrate temperature resulted in the simultaneous deposition of well-faceted MCD films in some areas with nanograined NCD films in others. Dilution of methane/hydrogen microwave plasmas by as much as 94% of argon alone could not suppress the growth of MCD. [Copyright &y& Elsevier]

Line clipping against a polygon is widely used in computer graphics such as the hidden line problem. A new line–clipping algorithm against a general polygon is presented in this paper. The basic idea of this algorithm is to change the line to be clipped into a horizontal line by shearing transformation. Then each edge of the polygonal window is transformed by a shearing transformation with the same parameters as those used to the line. Each edge of the polygon is processed against a horizontal line, which makes the clipping process simpler. The result in this paper shows that less calculation is needed for the new algorithm with a higher speed compared to existing algorithms. [ABSTRACT FROM AUTHOR]

Examines the Y chromosome microdeletions among infertile males in China. Ethnic differences of genetic abnormalities; Incidence of Y-microdeletions in azoospermic men; Derivation of genomic DNA from peripheral blood lymphocytes.

A diamond-coating layer is studied as a heat spreading layer for a thin-GaN light-emitting diode (LED) chip. Our results show that this diamond layer can effectively spread the heat and improve the temperature uniformity of a thin-GaN LED chip, which enhances the heat dissipation efficiency down to the heat sink. With the diamond heat spreading layer, the junction temperature of the thin-GaN LED was reduced by 20 C at 1-A current input and the uniformity of the temperature distribution is also greatly improved. [ABSTRACT FROM PUBLISHER]

Gradient stripe patterns of Single-Walled Carbon Nanotubes (SWCNTs) were fabricated by using the evaporation-induced self-assembly technique. Additionally, the nonvolatile thin-film transistors (TFTs) with SWCNTs and (Bi,Nd) 4 Ti 3 O 12 (BNT) insulators were fabricated. The retention characteristics were investigated in Pt/SWCNTs/BNT/LaNiO 3 and LaNiO 3 /SWCNTs/BNT/LaNiO 3 structures. Results revealed that LaNiO 3 /SWCNTs/BNT/LaNiO 3 TFTs demonstrate larger on-state current, wider memory window, better fatigue endurance performance and retention characteristics, compared with Pt/SWCNTs/BNT/LaNiO 3 TFTs because of the involvement of the oxide conductive electrodes. These results suggest that the SWCNTs/BNT TFTs with LaNiO 3 as the electrodes are suitable for next-generation nonvolatile memory devices and integrated circuits. [ABSTRACT FROM AUTHOR]