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Plate impact experiments are conducted on a metastable dual-phase high-entropy alloy (HEA) Cr 10 Mn 30 Fe 50 Co 10 with different matrix grain sizes and phase fractions. Free surface velocity histories are obtained along with microstructure characterizations. Postmortem samples are characterized with transmission electron microscopy and electron backscatter diffraction. Multiple deformation mechanisms are observed, including dislocation slip and stacking fault in the face-center cubic (FCC) phase, dislocation slip and deformation twinning in the hexagonal close-packed (HCP) phase, and the FCC to HCP transformation. For spallation, damage is ductile in nature. Despite different microstructures, micro-voids prefer to nucleate at high-angle grain boundaries within the FCC phase, leading to similar spall strength. Upon shock loading, a dynamic plastic deformation partitioning behavior among the two phases is observed; at high shock stress, denser dislocations in the HCP phase result in increased fractions of voids around the FCC/HCP phase interface and within the HCP phase during spallation damage. • C r10 M n30 F e50 C o 10 with different FCC grain sizes and phase fractions are obtained. • Damage is ductile in nature, spall strengths for different microstructures are similar. • Multiple deformation mechanisms are observed, including FCC to HCP transition. • A dynamic plastic deformation partitioning behavior in two phases is observed. [ABSTRACT FROM AUTHOR]

Previous experiment of shock compression of the mixture of carbon black and tetracyanoethylene produced clear evidence of a new structural unidentified cubic carbon phase. In this letter, we confirmed that the previously proposed C20-sc and its modifications are more proper than recently suggested BC12 for explaining such a novel simple cubic carbon sample. Most of the X-ray diffraction peaks from the experiment can be understood through the pure C20-sc and some others can be explained by its modifications with introduced interstitial atoms (C21-sc and C22-sc states). Our results also show that C20-sc, C21-sc and C22-sc are all dynamically stable and more favorable than BC12 in energy. Interestingly, we find that C21-sc is a promising superhard carbon conductor, which can be used as multi-functional material in extreme condition. We expect that our discoveries can raise further explorations of this shock-compressing experiment. [ABSTRACT FROM AUTHOR]

We propose the model of layered materials, in which each layer is described by the conventional Haldane model, while the inter-layer hopping parameter corresponds to the ABC stacking. We calculate the topological invariant N 3 for the resulting model, which is responsible for the conductivity of intrinsic quantum Hall effect. It has been shown that for a finite value of interlayer hopping parameter, the value of N 3 is equal to the number of layers multiplied by the topological invariant of each layer. At the same time this value may be calculated using the low energy effective theory. • We generalize the Haldane model to its multi-layer extension with ABC stacking. • In the resulting system the energy bands are analyzed. • The Hall conductivity is calculated for a wide range of parameters. [ABSTRACT FROM AUTHOR]

Conductivity of Integer Quantum Hall Effect (IQHE) may be expressed as the topological invariant composed of the two-point Green function. Such a topological invariant is known both for the case of homogeneous systems with intrinsic Anomalous Quantum Hall Effect (AQHE) and for the case of IQHE in the inhomogeneous systems. In the latter case we may speak, for example, of the AQHE in the presence of elastic deformations and of the IQHE in presence of magnetic field. The topological invariant for the general case of inhomogeneous systems is expressed through the Wigner transformed Green functions and contains Moyal product. When it is reduced to the expression for the IQHE in the homogeneous systems the Moyal product is reduced to the ordinary one while the Wigner transformed Green function (defined in phase space) is reduced to the Green function in momentum space. Originally the mentioned above topological representation has been derived for the non-interacting systems. We demonstrate that in a wide range of different cases in the presence of interactions the Hall conductivity is given by the same expression, in which the noninteracting two-point Green function is substituted by the complete two-point Green function with the interactions taken into account. Several types of interactions are considered including the contact four-fermion interactions, Yukawa and Coulomb interactions. We present the complete proof of this statement up to the two loops, and argue that the similar result remains to all orders of perturbation theory. It is based on the incorporation of Wigner–Weyl calculus to the perturbation theory. We, therefore, formulate Feynmann rules of diagram technique in terms of the Wigner transformed propagators. • The topological expression for the Hall conductivity is given through the two-point Green function. • This representation has been proposed originally for the non-interacting systems. • In the present paper we consider the effect of interactions on this expression. • The only modification to be done is the substitution of the complete interacting Green function instead of the non-interacting one. • We prove this statement to all orders of perturbation theory. • It follows that the interactions do not affect perturbatively the Hall conductivity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Dynamical stability of fully hydrogenated graphyne is studied. [•] Zero-point energy is essential for determining the stability of hydrogenated graphyne. [•] Band-gap undergoes direct–indirect–direct transition with the increase of H coverage. [Copyright &y& Elsevier]

Abstract: Using the density functional theory in combination with the nonequilibrium Green’s function method, we investigate the transport properties of zigzag-edged graphene nanoribbons (ZGNRs) with oxygen edge decoration (passivated by the ketone (Cer (C–O–C), denoting as ZGNR-CO and ZGNR-C2O, respectively). We find that both ZGNR-CO and ZGNR-C2O induce the semiconductor-metal transition and enhance the transmission conductance within ‘transparent’ electrodes. However, sandwiched by Au (111) electrodes, Au∣ZGNR − CO∣Au enhances the transport properties while Au∣ZGNR − C2O∣Au depresses the transport properties in comparison with Au∣ZGNR − H∣Au. It is found that the transport properties of the edge oxidized ZGNRs within Au (111) electrodes depend on the electronic states around the Fermi level which determine the number of the effective transport channels. The states of Au∣ZGNR − CO∣Au are delocalized on the edge oxygen atoms as well as the inner edge carbon atoms, introducing extra transport channels. Moreover, in comparison with Au∣ZGNR − H∣Au, the effective transport channels of Au∣ZGNR − CO∣Au increase at given applied bias. However, the states of Au∣ZGNR − C2O∣Au are localized on the ribbon, blocking the effective transport channels. [Copyright &y& Elsevier]

Abstract: The electronic structures and transport properties of single-walled carbon nanotube ( (SWNT)) with oxygen-containing defect complex are investigated using density functional theory in combination with nonequilibrium Greenʼs function method. The complex delocalizes the local states of SWNT induced by mono- and di-vacancy but strengthens the localization of the states induced by the Stone–Wales defect. As a result, the complex partially restores the transport properties of SWNT with vacancies, but reduces the transmission of SWNT with Stone–Wales defect. However, the oxygen-containing defect complex only slightly influences the transmission gap and threshold voltage of the system. [Copyright &y& Elsevier]

Abstract: From the late 1970s to the present, a large-scale afforestation program called the “Three Norths Forest Shelterbelt” program was carried out to combat desertification and control dust storms in China. However, few detailed and systemic assessments have evaluated its success despite the huge investment in the program, its long-term, the extensive area covered by the program, and the importance of combating desertification and controlling dust storms. Although numerous Chinese researchers and government officials have claimed that the afforestation has successfully combated desertification and controlled dust storms, there is surprisingly little unassailable evidence to support their claims. Using basic data on afforestation, desertification, and dust storms, we assessed the effects of this afforestation on combating desertification and controlling dust storms. Although the large-scale afforestation program may have had some beneficial effects on reducing dust storms and controlling desertification in China, the results of our analysis suggest that the importance of this project seems to have been overstated. Thus, future research must seek stronger and more direct evidence for the causal relationships that we have proposed as possible explanations for the observed trends, and the true significance of the Three Norths program should be reassessed. [Copyright &y& Elsevier]

Abstract: Polycrystalline powder samples of terbium doped Zn(BO2)2 phosphors were prepared by solid state reaction in the thermal carbon reducing atmosphere at high temperature. The photoluminescence (PL), three-dimensional (3D) TL emission spectrum and dosimetric characteristics following 60Co gamma-rays irradiation were studied. Characteristic emission bands of Tb3+ at about 490, 543, 584 and 620nm, attributed to the 5D4→7F J (J=3, 4, 5, 6) transitions of Tb3+ ions, were observed in the TL and PL emission spectrum. No emission from Tb4+ ions was observed in the TL emission spectrum. The TL-dose response of the powder samples Zn(BO2)2:Tb to 60Co gamma-rays radiation in the dose range from 1 to 100Gy for clinical dose levels was almost linear. The experiment results showed that Zn(BO2)2:Tb has potential use as the materials of gamma-rays thermoluminescence dosimeter (TLD) for clinical dosimetry. [Copyright &y& Elsevier]

Lauryl tert-butylated hydroquinone (LTBHQ) and its oxidized compound, lauryl tert-butylated quinone (LTBQ) were synthesized from tert-butylated hydroquinone (TBHQ) and lauryl alcohol. Their antioxidant activities were investigated. At temperatures higher than 140 °C, the antioxidant activity of LTBHQ and LTBQ was higher than TBHQ. In emulsions, these two compounds had stronger antioxidant activity than TBHQ, butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA). [Copyright &y& Elsevier]

We investigate the effect of geometric anisotropy on the optical nonlinearity enhancement for a periodic composite with a rectangular array of elliptic semiconducting cylinders in an insulating host. By using a series expression of the space-dependent electric field obtained by a simple Fourier method in a periodic composite, we calculate the frequency dependence of the effective third-order nonlinear susceptibility as a function of anisotropy. The results show that the height of the nonlinearity enhancement peak may be increased by several orders of magnitude as the aspect ratio of the ellises is decreased or the lattice edge length ratio is increased. At resonance frequency, there exists a strong anomalous dispersion. We also investigate the effect of the volume fraction of the semiconductor phase for composites with a square array of circular semiconducting cylinders. [ABSTRACT FROM AUTHOR]

Thermal shock failure is the most common type occurring in service. The thermal shock life is overestimated and the failure process of thermal barrier coatings (TBCs) is still not clear due to lack of environmental simulator and the real-time detection methods. In this work, the damage evolution and failure mechanism of EB-PVD TBCs coated on a turbine vane under thermal shock is studied by acoustic emission combined with digital image correlation (DIC) method. Four damage modes are discriminated by spectrum of the acoustic emission signals, which are surface vertical cracks (200–220 kHz), sliding interfacial cracks (300–325 kHz), opening interfacial cracks (400–450 kHz) and substrate deformation (90–110 kHz). The principal strain of TBCs surface varies from compressive strain to tensile strain with increasing the thermal shock cycles. Furthermore, the thermal shock life is 710 cycles, and the exfoliation area is located in the middle of the leading edge. The failure mechanism is the propagation and coalescence of surface and interfacial cracks during the cooling stage due to the huge thermal gradient and stress concentration around the film holes. • The heating rate at the leading edge of a turbine vane is faster than that of other locations. • Four damage modes are discriminated by spectrum of the acoustic emission signals. • The principal strain of ceramic coating changes from compressive to tensile strain. [ABSTRACT FROM AUTHOR]

In the models defined on the inhomogeneous background the propagators depend on the two space–time momenta rather than on one momentum as in the homogeneous systems. Therefore, the conventional Feynman diagrams contain extra integrations over momenta, which complicate calculations. We propose to express all amplitudes through the Wigner transformed propagators. This approach allows us to reduce the number of integrations. As a price for this the ordinary products of functions are replaced by the Moyal products. The corresponding rules of the diagram technique are formulated using an example of the model with the fermions interacting via an exchange by scalar bosons. The extension of these rules to the other models is straightforward. This approach may simplify calculations in certain particular cases. The most evident one is the calculation of various non-dissipative currents. [ABSTRACT FROM AUTHOR]

First-principles calculations have been performed to investigate the reduction mechanism of hydroxyl group from graphene oxide (GO). We find that when the system is negatively charged the hydroxy group can be directly desorbed from GO due to the Coulomb repulsion derived from the extra charge accumulation between hydroxyl group and GO. And then we choose ammonia as the reducing agent for the hydroxyl group of GO. The results of substitution energy indicates that the –NH 2 group can easily substitute the –OH. Such substitution maybe a viable reduction process because –NH 2 group can also be easily reduced when the system is negatively charged. Both reduction mechanisms proposed in our present work involve negatively charged state which provide hint to understand the GO reduction in experiment. [ABSTRACT FROM AUTHOR]

Detached eddy simulation (DES) of the liquid-phase turbulent flow in an unbaffled stirred tank agitated by a six-blade, 45°-pitched blade turbine was performed in this study. The tank wall is cylindrical with no baffle and the fluid flow problem was solved in a single reference frame (SRF) rotating with the impeller. For the purpose of comparison, computation based on large eddy simulation (LES) was also carried out. The commercial code Fluent was used for all simulations. Predictions of the phase-averaged turbulent flow quantities and power consumption were conducted. Results obtained by DES were compared with experimental laser Doppler velocimetry (LDV) data from the literature and with the predictions obtained by LES. It was found that numerical results of mean velocity and turbulent kinetic energy profiles as well as the power consumption are in good agreement with the LDV data. When performed on the same computational grid, which is under-resolved in the sense of LES, DES allows better accuracy than LES in that it works better in the boundary layers on the surface of the impeller and the stirred tank walls. It can be concluded that DES has the potential to predict accurately the turbulent flow in stirred tanks and can be used as an effective tool to study the hydrodynamics in stirred tanks. [ABSTRACT FROM AUTHOR]

Abstract: Using first-principles method within the framework of the density functional theory, we study the formation energies and the binding energies of hydrogen–telluride antisite complex impurities (n H–Te Hg , n=1,2) in Hg0.75Cd0.25Te. We find that telluride antisite impurity (Te Hg ) in Hg0.75Cd0.25Te is a double donor. When Te antisite and an interstitial hydrogen move close to each other, the interaction between them leads to the creation of a stable 1H–Te Hg complex with a binding energy of 0.33eV. In this case, the donor effects induced by Te antisite are partially passivated. As the hydrogen concentration increases, the binding energy of the 2H–Te Hg forming from combining H–Te Hg with interstitial hydrogen is only 0.005eV. Namely, 2H–Te Hg is unstable in Hg0.75Cd0.25Te and hydrogenation cannot fully neutralize Te antisite defects. [Copyright &y& Elsevier]

The effects of the surfactant sodium dodecyl sulfonate (SDS) on NiO–TiO2 sols, xerogels and films have been studied. Xerogels and films with Ni concentration of 80mol% have been prepared using sols containing 3, 6, 9wt% of SDS added to nickel acetate tetrahydrate (Ni(CH3COO)2·4H2O) and tetra-n-butyl titanate (TNBT) as precursors in a mixture of ethanol and n-butanol. The thermal analysis of dried xerogels has been measured by thermogravimetry (TG) and differential thermal analysis (DTA) in air up to 500°C. The structural properties of xerogels sintered at 300°C have been determined by XRD and the xerogels consist predominantly of bunsenite nanoparticles embedded in an amorphous TiO2 phase. Single layers have been deposited by dip coating on FTO (fluorine doped tin oxide, SnO2:F) coated glasses and sintered at 300°C. Their thickness is found to increase with the SDS amount while the roughness of the surface is reduced. The electrochromic properties of films deposited on FTO coated glasses have been studied in 1M KOH aqueous electrolyte via cyclic voltammetry (CV), chronoamperometry (CA) and visible light transmission. The anodic and cathodic peaks in CV cycles and the charge intercalated during CA cycles increase with the SDS content. The transmission in the bleached and colored states as well as the change in optical density remain stable for the film prepared with 9wt% SDS up to almost 18,000 CA cycles, a great improvement compared to films prepared without surfactant. The coloration efficiency of the film prepared with 9wt% SDS is about 30cm2/C, a value comparable to that obtained for pure NiO film. [ABSTRACT FROM AUTHOR]

Abstract: Using the first-principle calculations, the stability and electronic properties of two novel types of four-segment armchair (10, 10) BN/C hybrid nanotubes ((BN)5C5(BN)5C5NT and (BN)5C5(NB)5C5NT) as well as two-segment armchair (10, 10) BN/C hybrid nanotubes () are systematically investigated. When n increases from 1 to 4, the band gap of gradually decreases to a narrow one. When , the electronic structure of carbon segment in behaves as zigzag graphene nanoribbons whose band gap is modulated by an inherent electric field of the BN segment. ZGNR-like segments in (BN)5C5(BN)5C5NT and (BN)5C5(NB)5C5NT behave as narrow gap semiconductor and metal, respectively, due to their different chemical environment. Moreover, the (BN)5C5(NB)5C5NT can separate electron and hole carriers, indicating its potential application in solar cell materials. Obvious transport enhancement around the Fermi level is found in the four-segment nanotubes, especially a 6G0 transmission peak in the metallic (BN)5C5(NB)5C5NT. [Copyright &y& Elsevier]

Abstract: A 3×3 factorial experiment has been conducted to study the effects of different transport time (Short: 40min vs. Medium: 3h vs. Long: 5h) and stocking densities (Low: 5 pigs per pen or 230kg/m2, Medium: 6 pigs per pen or 275kg/m2 and High: 7 pigs per pen or 325kg/m2) on some blood constituents and meat quality of four hundred and thirty two pigs including seventy two pigs that had been DNA tested (genotype: NN). The results are as follows: 1) Lactate dehydrogenase enzymatic activity increased as transport time increased, but it reached significance only for the high density group (P< 0.05). Lactate concentration was significantly lower in the group subjected to 3h transport and low stocking density (P< 0.05). The concentration of cortisol was higher after 5h transport than those transported for shorter time (40min or 3h; P< 0.05) and also significantly increased (P< 0.05) in the highest stocking density. The stocking density treatment had a difference tendency that ACTH concentration gradually increased as density enhanced. 2) Drip loss, pHu and Opto-staru were significantly affected by transport time in the longissimus thoracis muscle. Opto-staru was the only meat quality that was affected by transport time in the semimembranosus muscle, while the values of pH1, pHu, Opto-star1 and Opto-staru were lower (P< 0.05) in the low density group than medium or high density group. 3) The pigs from the 3h transport group had significantly lower RBC, HGB and HCT (P< 0.05) compared with the short or long time transport groups. At the same time, pigs under the long time transport showed lower count of LYM than pig under 1 and 3h transport conditions. Hence, from these data we conclude that the most adequate pre-slaughter transport time was 3h for medium stocking density (less than 275kg/m2) and at a warm environmental temperature in the Chinese commercial transport conditions. [Copyright &y& Elsevier]

For decades, hydrogen has been identified as the most promising potential fuel to replace fossil fuels. In order to fully implement it and to promote the rationality of the design of hydrogen combustion chamber structure, it is very essential to understand the hydrogen/air combustion mechanism based on structural variations. The structural characteristics of a novel dual-swirl burner for hydrogen-air non-premixed combustion was studied numerically in this study. The influences of air distributions, swirling directions and nozzle configurations of the dual-swirl burner were studied, and the combustion performance was evaluated from various aspects. The numerical results showed that there was a trade-off between lower total pressure loss and the risk of fusing when considering air distribution strategies. The co-rotating swirl burner exhibited better uniformity of temperature distribution at the downstream of the combustor. The multi jet orifices showed superior penetration depth than the circular seam. Efficient and stable combustion could be achieved, which was beneficial to improve gas turbine efficiency and stable operation. • Flow losses and the flame position can be adjusted by air distribution strategies. • The swirling direction affects the downstream mixing, but has limited influence on the upstream flame shape. • The multi fuel jet orifices show superior penetration depth than the circular seam. [ABSTRACT FROM AUTHOR]

A compact branch‐line coupler with an ultra‐wide upper stopband is proposed based on a new type of transmission line. Consistent numerical and measurement results of the coupler are shown. The proposed branch‐line coupler operating at 0.875 GHz exhibits a stopband from 2.8 to 12.9 GHz with suppression levels better than −20 dB. The occupied size of the proposed branch‐line coupler is only 17.6% that of a conventional one operating at the same frequency. [ABSTRACT FROM AUTHOR]

• The effects of different proportion of buckwheat straw on growth performance of sheep were investigated. • The effects of different proportion of buckwheat straw on rumen fermentation parameters and enzyme activities were analyzed. • The changes of rumen microbiota composition of sheep were also evaluated. This experiment was conducted to investigate growth performance, nutrient digestibility, rumen fermentation, and microbiota composition when different proportions of buckwheat straw (BS) and corn straw (CS) were included in the diet of male lambs. A total of sixty 1/2 Dorper× 1/2 Small Thin-Tailed male lambs (150 d of age; 25 ± 1 kg of BW; mean ± SD) were selected and divided into five groups, and were allocated to 1 of 5 treatment diets randomly. Diets were formulated containing different levels of BS: 1) 0% of BS (control diet, C); 2) 13.7% BS (14BS); 3) 27.5% BS (28BS); 4) 41.2% BS (41BS); and 5) 55.0% BS (55BS). Diets were isonitrogenous, with a forage-to-concentrate ratio of 55:45 (air-dry basis). For dry matter intake and average daily gain, quadratic (P < 0.01) effects were observed among treatments. Therefore, response to inclusion level of BS was quadratic (P < 0.01) for the feed efficiency with the greatest value at intermediate BS levels. The concentrations of rumen total volatile fatty acids, ammoniacal nitrogen, and microbial protein responded quadratically (P < 0.05) across BS levels, with the greatest total VFA, ammoniacal nitrogen, and microbial protein production for 28BS. For the carbohydrate hydrolytic enzyme activities, BS displayed quadratic response, with the highest values at 28BS diet. Moreover, feeding BS at increasing inclusion levels resulted in a linear decrease in bacterial diversity. The relative abundance of Prevotella, Butyrivibrio, Coprococcus, Ruminococcus were linearly (P < 0.05) decreased, and some pernicious bacteria like Sutterella, Helicobacter, Akkermansia were increased linearly (P < 0.05). Thus, it appears that BS can be used as a forage resource for sheep and the optimal proportion in diet was 28% under the test condition. [ABSTRACT FROM AUTHOR]

Highlights • Energy and nitrogen loss in feces were high for lambs fed the diet containing 24% SBP. • The metabolisable energy intake and heat production were not affected by SBP level. • The highest values of retention of energy in fat and total tissue were observed in the diet containing 16% SBP. Abstract This experiment investigated the effects of dietary sea buckthorn pomace (SBP) supplementation on energy partitioning, substrate oxidation, and carbon and nitrogen balance in ram lambs. A total of 40 1/2 Dorper × 1/2 thin-tailed Han male lambs (BW = 22.2 ± 0.92 kg, Age = 120 ± 11 d; mean ± SD) were randomly selected and equally divided into 4 groups. Diets were formulated isonitrogenously and contained different levels of SBP: 1) 0% SBP (control); 2) 7.8% dry matter (DM) SBP (8SBP); 3) 16.0% DM SBP (16SBP); and 4) 23.5% DM SBP (24SBP). The lambs were fed in individual stalls for 50 d and then determine nutrients digestibility. Gas exchange was then determined using a polycarbonate head box designed for small ruminants. DM and crude protein (CP) intake were greater for 24SBP (2.1 and 0.29 kg/d) than for control (1.28 and 0.24 kg/d) or 8SBP (1.84 and 0.24 kg/d). The treatment diets did not result in difference in metabolisable energy (ME) intake and heat production (HP). Energy and nitrogen loss in feces were higher for lambs fed the 24SBP than for other groups. The nutrient oxidation contribution to the heat production (OXP/HPx, OXCHO/HPx, and OXF/HPx) was not affected by treatment diets (P > 0.228). The highest values of retention of energy in fat (RE fat) and total tissue (RE total) were observed in 16SBP diet. The results indicated that sea buckthorn pomace can be incorporated in the diet of ram lambs, and inclusion of 16% SBP in the diet had no detrimental effect on energy metabolism and resulted in an increase in energy retention. [ABSTRACT FROM AUTHOR]

Abstract The influence of (Ti,V)N- and V(C,N)-type precipitates on the mechanical properties was studied using transmission electron microscopy, energy-filtered transmission electron microscopy, and electron energy-loss spectroscopy for four medium carbon 1Cr steels containing various amounts of vanadium and nitrogen in the hot-rolled and normalized states. (Ti,V)N-type nanoparticles were found only in the proeutectoid ferrite, while V(C,N)-type nanometer precipitates were distributed in ferrite and further promoted the transformation of pearlite. Addition of vanadium and nitrogen refined the size of the precipitates and increased the volume fraction of pearlite, leading to increased strength. A linear arrangement of (Ti,V)N nitrides and V(C,N) carbonitrides was observed after normalization and resulted in an increase of elongation-to-failure from 16% to 22% at the expense of a 103 MPa decrease in the strength. The precipitation mechanism of Ti-rich nitrides and V-rich carbonitrides and their effects on the mechanical properties of the ferrite-pearlite 1Cr steels were discussed. [ABSTRACT FROM AUTHOR]

The irreversible hydrogen traps including Cr-rich M 7 C 3 , Mo 2 C and MC carbides are characterized by scanning transmission electron microscope (STEM) after the quenching-and-tempering process performed on the API-5CT-C110 casing steel. Combined with our previously published work [Mater. Sci. Eng. A 688 (2017) 378–387], a systematic analysis with respect to the hydrogen interactions with reversible traps (grain boundaries and dislocations) and precipitates influencing sulfide stress cracking (SSC) behavior is presented. Grain boundaries provide channels for hydrogen diffusion. Dislocations trap hydrogen and act as hydrogen “transporters” during moving. Precipitates are introducing traps to retain hydrogen and restrict dislocation movement, then improve resistance to SSC. However, the mobile dislocations can transport the trapped hydrogen from precipitates into potential crack sites in the presence of external stress, leading to the initiation of SSC cracks. Therefore, SSC susceptibility significantly depends on the density of dislocations. The steel with lower dislocation density exhibits superior SSC behavior mainly attributed to its finite hydrogen “transporters”. [ABSTRACT FROM AUTHOR]

Wine grape pomace (WGP) provides a rich source of polyphenols that can act as powerful antioxidants, but their potential as feed ingredients in the lamb industry remains unexploited. The objective of this study was to investigate the effect of dietary WGP supplementation on growth performance, meat quality and antioxidative activity in the longissimus dorsi (LD) muscle of lambs. A total of eighteen lambs (25.0 ± 0.2 kg of body weight, BW) were randomly selected and equally divided into three groups, and offered diet containing different levels of WGP (0%, 5% and 10%). The results showed that supplementation with 10% dietary WGP increased body weight, average daily gain, and reduced the feed to gain ratio (P < 0.05). There was no observed effect of dietary WGP supplementation on pH, color, cooking loss, or intramuscular fat (IMF). Lambs fed with a WGP-containing diet had lower Warner–Bratzler shear force (WBSF) (P < 0.05), and a decreased collagen content (P < 0.05). The total antioxidative capacity (T-AOC), glutathione peroxidase 4 (GPx4) and superoxide dismutase (SOD) activity were increased when lambs were fed the WGP-containing diet (P < 0.05), whereas no difference in catalase activity was detected. In addition, WGP supplementation decreased ROS and MDA levels induced in animals raised in penned conditions (P < 0.05). Taken together, these results suggest that WGP can be used as a feed ingredient in lamb production to relieve oxidative stress, and improve feed efficiency and meat tenderness, possibly due to the enhanced antioxidative capacity. [ABSTRACT FROM AUTHOR]

The evolution of the microstructure and crystallography in SAE1078 pearlitic steel sheets under different cold-rolling reductions of up to 90% were quantified using transmission electron microscopy (TEM), electron backscatter diffraction (EBSD), and X-ray diffraction (XRD). The mechanical properties were determined by tensile testing at room temperature. TEM analysis showed that the pearlite structure was obviously refined with the interlamellar spacing decreasing to about 57 nm at the rolling reduction of 90%. EBSD investigations indicated that the ferrite exhibited a {001} <110> texture in the 90% cold-rolled pearlitic steel. The dislocations were mainly concentrated during cold rolling between the 10% and 70% reduction ratios as the average kernel average misorientation (KAM) angle increased from 0.75° to 1.20°. XRD examination revealed that a transformation from bcc to bct crystal structure of ferrite occurred at 90% rolling reduction due to the supersaturation of carbon. Significant augmentation in the ultimate tensile strength during cold rolling results from the boundary, dislocation, and solid solution strengthening mechanisms. [ABSTRACT FROM AUTHOR]

This work investigates microstructures, precipitates, and mechanical properties in 1Cr low alloy steel undergoing normalizing, quenching, and quenching-tempering treatments. The precipitated phases in these samples were removed by electrolytic extraction and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The precipitates extracted from the normalized and tempered samples were mainly M 3 C cementite, while the major precipitates obtained from the quenched sample were identified as Nb-rich MC carbides. Energy dispersive X-ray spectroscopy (EDXS) semi-quantitatively analyzed the ratios of Fe atoms to Cr atoms in relevant phases, revealing that redistribution of Cr occurred in the tempering process but not in the normalizing or quenching processes. The tempered sample contained M 3 C carbide with a {022} twin plane and a hexagonal M 7 C 3 -type phase. Strength and elongation in the quenched sample were larger than these in normalized sample, but a significant reduction in strength and a dramatic increase in elongation occurred when the as-quenched sample was tempered. [ABSTRACT FROM AUTHOR]

A 9-week feeding experiment was conducted to determine the effect of dietary biotin levels on growth performance and non-specific immune response of large yellow croaker. Fish (6.16 ± 0.09 g) were fed twice daily to apparent satiation with diets containing 0.00 (as the basal diet), 0.01, 0.05, 0.25, 1.24 and 6.22 mg biotin kg−1 diet. Results showed that fish fed the basal diet had the lowest survival rate, and fish fed 0.05 mg kg−1 dietary biotin achieved significantly higher final weight and weight gain. Dietary biotin levels had no significant influence on carcass crude lipid, moisture and ash content, but significantly influenced the carcass crude protein. Liver biotin concentration significantly increased with the supplementation of biotin, but no tissue saturation was found within the supplementation scope of biotin. Broken-line regression analysis of weight gain showed that juvenile large yellow croaker requires a minimum dietary biotin of 0.039 mg kg−1 for maximal growth. The analyses of serum parameters showed that the moderate- (0.05 mg kg−1) and high-dose (6.22 mg kg−1) dietary biotin significantly improved both lysozyme and alternative complement pathway activities, indicating dietary biotin within a certain range could improve the non-specific immune response of large yellow croaker. [ABSTRACT FROM AUTHOR]

Separation of squalene, a type of terpenoid hydrocarbons with important biological properties, from camellia oil by silver ion complexation was studied. We showed that the UV–visible absorption wavelength of squalene in AgNO 3 -methanol solution was obviously red-shifted, and the infra-red vibration wavelength of C C bond slightly decreased, indicating that complexation between squalene and Ag + took place. The distributions of squalene in AgNO 3 methanol solution/petroleum ether under different conditions were further investigated. We found that the fraction of squalene in AgNO 3 -methanol phase was enhanced with increased percentage of methanol and AgNO 3 concentration and decreased extraction temperature. The distribution coefficient of squalene was up to 7.87 under optimum extraction conditions with 70% methanol (v/v), 0.6 mol/L AgNO 3 , reaction time of 12 h, and at the temperature of 0 °C. Furthermore, under the optimum conditions, extraction of squalene from the unsaponifiable portion of camellia oil exhibited high selectivity with a raffinate rate and a back-extraction rate of 73.9% and 72.5%, respectively. The purity of extracted squalene was 37.8%, 108 times more concentrated than that in the starting material. [ABSTRACT FROM AUTHOR]

Abstract: The transport properties of graphene/metal (Cu(111), Al(111), Ag(111), and Au(111)) planar junction are investigated using the first-principles nonequilibrium Green's function method. The planar junction induce second transmission minimum (TM2) below the Fermi level due to the existence of the Dirac point of clamped graphene. Interestingly, no matter the graphene is p- or n-type doped by the metal substrate, the TM2 always locates below the Fermi level. We find that the position of the TM2 is not only determined by the doping effect of metal lead on the graphene, but also influenced by the electrostatic potential of the metal substrate and the work function difference between the clamped and suspended graphene. [Copyright &y& Elsevier]

Abstract: Using first-principles calculations within the framework of density-functional theory, we systematically study the modulation effect of chemical decoration including hydrogenation, fluorination, and oxidization on the surface work function of graphene. The chemical decoration is effective approach to modulate the surface work function, which expands the space to design diverse nano-devices based on graphene. Moreover, we also find some un-expectation chemically decorated cases which do not follow the traditional rule of “electronegative (electropositive) adsorbates, which increase (decrease) the work function of the surface”. Such a phenomenon is mainly derived from the charge redistribution induced by the bonding process between adsorbates and carbon atoms along with the chemical decoration. [Copyright &y& Elsevier]

First principles calculations based on the density functional theory are performed to study electronic structures of graphene adsorbed on clean or C-decorated Si(111) surface. Two types of surface reconstructions, 2 × 2 and , are considered to be decorated by carbon atoms with different concentrations. We find that graphene adsorbed on ideal clean Si(111) surface tends to induce a 2 × 1 reconstruction, and its electronic dispersion characteristics are preserved. Moreover, the decoration of carbon atoms on the Si(111) surface can effectively passivate the Si dangling bonds on the surface. Such decoration effects make the carbon decorated Si(111) surfaces promising substrate for graphene preserving its excellent electronic structure. [ABSTRACT FROM AUTHOR]

Abstract: Charge pumping (ACIV) and direct current–voltage (DCIV) measurements were performed on standard floating-body n-channel FinFETs. The resulting recombination currents are monitored directly at the drain and source contacts, and are found to depend strongly on frequency, gate voltage, and FinFET geometry. The DCIV current reaches a maximum when the body potential transitions from accumulation to inversion in response to the applied gate bias and the body-to-source and body-to-drain diodes become forward biased. The ACIV current is dominated by contributions from interface traps when the surface potential is swept from accumulation to inversion during the gate pulse. It is sensitive to recombination currents at the body-to-source and body-to-drain diodes at intermediate voltage levels. At the highest applied gate voltages, band-to-band tunneling is also observed. We demonstrate that the change in ACIV current with frequency before and after electrical stress allows charge-pumping estimates of stress-induced interface trap densities in standard SOI FinFETs without body contacts. [Copyright &y& Elsevier]

Abstract: This report provides a progress update of a consortium effort to develop a harmonized zebrafish developmental toxicity assay. Twenty non-proprietary compounds (10 animal teratogens and 10 animal non-teratogens) were evaluated blinded in 4 laboratories. Zebrafish embryos from pond-derived and cultivated strain wild types were exposed to the test compounds for 5 days and subsequently evaluated for lethality and morphological changes. Each of the testing laboratories achieved similar overall concordance to the animal data (60–70%). Subsequent optimization procedures to improve the overall concordance focused on compound formulation and test concentration adjustments, chorion permeation and number of replicates. These optimized procedures were integrated into a revised protocol and all compounds were retested in one lab using embryos from pond-derived zebrafish and achieved 85% total concordance. To further assess assay performance, a study of additional compounds is currently in progress at two laboratories using embryos from pond-derived and cultivated-strain wild type zebrafish. [Copyright &y& Elsevier]

Abstract: Using local density approximation (LDA) within the framework of density functional theory, we investigate the response of the electronic and optical properties of hexagonal boron nitride to external uniaxial strain along c-axis. Five typical stable stackings are considered. The band gap of all the five stackings decreases as the uniaxial pressure increases, and the band gap of AA, AE and AF reduce faster than that of the others. We find that the response of band dispersion of AB to the uniaxial compression is different from that of the others. The band-edge absorption threshold of AB red shifts initially and starts to blue shift at 10.53GPa, whereas the threshold of the other stackings only shows red shift under the uniaxial pressure. The band structure of AA changes from indirect to direct when the uniaxial pressure is larger than 6.55GPa. Moreover, the band structure of AE changes from quasi-direct to indirect under the uniaxial compression. [Copyright &y& Elsevier]

Abstract: We report on the temperature dependent lasing characteristics of InAs/GaAs quantum dot lasers under continuous wave mode. The five-stacked InAs quantum dots were grown by gas-source molecular beam epitaxy with slightly different thickness. Ridge waveguide laser with stripe width of 6μm was processed on the growth structure. The characteristic temperature was measured as high as infinity in the temperature range of 80–180k. With the increase of injection current, the lasing spectra of laser diode broaden gradually at low temperature of 80k. However, when the operation temperature increases from 80 to 300K, the width of lasing spectrum reduces gradually from 40 to 2.0nm. The lasing process is obviously different from that of a reference quantum well laser which widens its width of lasing spectra by increasing operation temperature. These experiments demonstrate that a carrier transfer from the smaller size of dots into larger dots caused by thermal effect play an important role in the lasing characteristic of quantum dot lasers. In addition, the laser can operate at maximum temperature of 80°C under continuous wave mode with a maximum output power of 52mW from one facet at 20°C. A wavelength thermal coefficient of 0.196nm/K is obtained, which is 2.8 times lower than that of QW laser. The low wavelength thermal coefficient of quantum dot laser is mainly attributed to its broad gain profile and state filling effects. [Copyright &y& Elsevier]

Abstract: Electronic properties of hexagonal boron nitride (h-BN) with stacking fault have been systematically studied using the first-principles method. The formation energy of a single layer stacking fault in five typical stacking h-BN (AA, AB, AD, AE and AF) ranges from −58 to 55meV, which indicates that the stacking fault can be easily introduced into the material. Amazingly, we find that as long as AA, AB, AD and AF stacking h-BN with AE-liked stacking fault they are similar to AE stacking with or without stacking fault behaving as quasi-direct or direct semiconductor. We predict that the AE-liked stacking sequence may be the primary reason for the inconsistency between theoretical and experimental reports according to the type of the band gap of h-BN. [Copyright &y& Elsevier]

Abstract: Highly monodisperse colloidal silica spheres in submicron size were synthesized by a chemical method and close-packed face-centered-cubic photonic crystals (PCs) were prepared. Tris (8-hydroxyquinoline) aluminum (Alq3) has been in-filled in this structure to investigate the photonic band gap effect on the spontaneous emission. Because of the overlap of the photonic band gap and the photoluminescence (PL) band of Alq3, both suppression and enhancement in the photoluminescence of the organic molecules were observed. The PL of Alq3 molecules in PCs exhibited a small blue shift compared with the ones deposited on glass slide, which was believed to arise from the reduced interaction between organic molecules. [Copyright &y& Elsevier]

Abstract: The Sr2Mg(BO3)2 phosphors doped respectively with Tm3+, Tb3+ and Dy3+ as activator were prepared by high temperature solid-state reaction. All the thermoluminescence curves of the phosphors consisted of two isolated peaks and the Dy3+ activated sample exhibited the strongest thermoluminescence intensity. The kinetic parameters of the thermoluminescence of Sr2Mg(BO3)2 :0.04 Dy were calculated employing the peak shape method and 3 dimensional thermoluminescent emission spectra were observed peaking at 480, 579, 662 and 755 nm due to the characteristic transition of Dy3+. In addition, the pre-irradiation heat-treatment and the thermoluminescence dose response of Sr2Mg(BO3)2 :0.04 Dy were investigated. [Copyright &y& Elsevier]

Abstract: A two-dimensional photonic crystal heterostructure with a large complete photonic bandgap is presented. It consists of two photonic crystals, whose dielectric configurations are reverse, with triangular lattice of circular columns. The structure retains the ease of fabrication while increasing the maximum quality factor of the gap 2–3 times after optimization. Photonic bandgap properties are calculated using a plane-wave method and the transmission spectra are obtained. [Copyright &y& Elsevier]

Abstract: In this paper TL studies of doped compound are reported by -ray irradiation for the first time. The polycrystalline powder samples of dysprosium doped :Dy phosphor were prepared by a solid-state reaction in air at high temperature and the TL glow curves and TL emission spectrum after -ray irradiation was studied from 50 to 250kGy dose range. The TL studies of sample show main TL glow peak at 497K, and the 497K glow peak show great stability for a long time. The trap parameters namely activation energy , order of kinetics , and frequency factor of main peak of the sample at 497K were determined using glow curve shape (Chen''s) methods. The TL emission bands at about 480, 575, 660 and 750nm of the :Dy phosphor is attributed to the characteristic emission from f–f transitions of ion. The distributions of trap produced by the irradiation of -ray can be altered greatly by the change of the concentrations of ion doped in host and, all peak temperatures shift to higher temperature, this will be favorable for TL output. The TL-dose response of the :Dy polycrystalline powder sample to -ray radiation in the range from 50 to 250kGy for radiation processing dose levels is almost linearity. The experiment results showed that :Dy potential use as the materials of -ray thermoluminescence dosimeter (TLD) for radiation processing dosimetry. [Copyright &y& Elsevier]

The objective of the study was to determine the long-term effects of melatonin treatment on cashmere production and hair follicle populations in cashmere goats and their activity in two consecutive cashmere growth cycles. Twenty-four female Inner Mongolian Cashmere goats were randomly allocated to two groups (n = 12), one of which received melatonin implants, the other being an untreated control group. Melatonin implants were subcutaneously inserted behind the ear at a dose of 2 mg/kg live weight on two occasions –April 30 and June 30, 2016. Hair samples were collected by combing in April of 2017 and 2018, and the weight, staple length, and diameter of the cashmere fibers were measured. Blood and skin samples were collected monthly between April and September 2016, and in April and September in 2017 for the analysis of melatonin concentration and the characteristics of secondary hair follicle populations, respectively. The results indicated that serum melatonin concentration in the treated goats was elevated (P < 0.05) relative to that of the control group, but only during the first growth cycle. Melatonin treatment of cashmere goats in one cashmere growth cycle increased the weight, staple length, and density (all P < 0.05) of the cashmere fibers and decreased fiber diameter (P < 0.01), but did not affect the characteristics of cashmere production in the subsequent annual cycle. Melatonin treatment had no effect on the population of skin secondary hair follicles for two consecutive cycles. However, in the first growth cycle after treatment, it advanced the onset of activity of skin secondary hair follicles by 2 mo (P < 0.05), and it increased the number of follicles that were active (P < 0.05). In summary, the melatonin treatment of cashmere goats in one cashmere growth cycle improved cashmere production for that cycle only, with no residual effects on the subsequent cycle, a technique acceptable to the cashmere goat industry. The enhancement of cashmere production after the treatment of goats with melatonin appears to involve the acceleration of the annual regeneration of skin secondary hair follicles and increased population of active secondary hair follicles in the skin of cashmere goats. • The effect of melatonin on cashmere does not maintain in the following annual cycle. • Melatonin accelerates the annual regeneration of skin secondary hair follicles. • Melatonin increases the population of active skin secondary hair follicles. [ABSTRACT FROM AUTHOR]