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Dyes, a kind of visible chemical, have severe deleterious effects on human health and ecological environment. In this work, batch biosorption experiments were carried out under various experimental conditions such as pH value and agitation time to optimize the potentiality of Enteromorpha prolifera for the removal of malachite green (MG) dye from aqueous solution (70·7%). Then, the algal biomass was treated with a dielectric barrier discharge (DBD) in helium for 4 and 10 min to enhance MG removal efficiency (84·7 and 96·6%). In addition, Fourier‐transform infrared spectroscopy in combination with scanning electron microscopy was employed to monitor the chemical and physical changes of algal cells treated by DBD. This study illustrates that DBD may serve as an effective tool to activate the functional groups on the cell wall surface for dye binding, and it even offers an alternative new technique to improve the adsorption properties of native biosorbents for the removal of toxic dyes from wastewater. [ABSTRACT FROM AUTHOR]

Isochronous Mass Spectrometry (IMS) in heavy-ion storage rings is an excellent experimental method for precision mass measurements of exotic nuclei. In the IMS, the storage ring is tuned in a special isochronous ion-optical mode. Thus, the mass-over-charge ratios of the stored ions are directly reflected by their respective revolution times in first order. However, the inevitable momentum spread of secondary ions increases the peak widths in the measured spectra and consequently limits the achieved mass precision. In order to achieve a higher mass resolving power, the ring aperture was reduced to 60 mm by applying a mechanical slit system at the dispersive straight section. The momentum acceptance was reduced as well as better isochronous conditions were achieved. The results showed a significant improvement of the mass resolving power reaching 5.2 × 10 5 , though at the cost of about 40% ion loss. [ABSTRACT FROM AUTHOR]

Abstract High-resolution digital image correlation (HR-DIC) techniques have become essential in material mechanics to assess strain measurements at the scale of the elementary mechanisms responsible of the deformation in polycrystalline materials. The purpose of this study is to demonstrate the use of laser scanning confocal microscopy (LSCM) coupled with DIC techniques to deepen knowledge on the deformation process of a polycrystalline nickel-based superalloy at room temperature. The LSCM technique is capable of detecting both in-plane and out-of-plane strain localization within slip bands at the sub-grain level. The LSCM observations are consistent with previous in-situ scanning electron microscopy (SEM) studies: The onset of crystal plasticity occurs primarily near Σ3 twin boundaries with macroscopic loading in the elastic domain (macroscopic stress as low as 80% of the 0.2% offset yield strength (Y.S. 0.2%)). This intense irreversible strain localization occurs with either a high Schmid factor (μ > 0.43) or a significant elastic modulus difference between the pair of twins (ΔΕ > 100 GPa). In the plastic deformation domain, transgranular slip activity following slip systems with the highest Schmid factor is mostly responsible for the deformation at the grain level, thus leading to strain percolation. The simultaneous in-plane and out-of-plane deformation assessment via the HR-LSCM-DIC technique was found to be essential for the identification of active slip systems. Finally, the HR-LSCM-DIC technique enabled the quantification of the glide amplitude involved in the three-dimensional shearing process at the grain level that solely in-plane measurements cannot provide. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • One-dimensional Ni microwires were synthesized by two-step MFI method. • Ni particles turned from nanospheres to microwires for magnetic field. • Brownian motion and magnetic moments affected the morphology of Ni microwires. • The length increased with magnetic field, while the diameter decreased. • The magnetic field improved the spontaneous magnetization of Ni microwires. Abstract One-dimensional nickel (Ni) microwires were synthesized by the magnetic-field-induced (MFI) microemulsion-hydrothermal method using Ni nanospheres as seeds. The influence of the chemical conditions and magnetic field on the morphology and magnetic properties of Ni microwires were investigated by X-Ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometry (VSM). The strength of magnetic field greatly affected the morphology and magnetic properties of Ni microwires. The growth and morphology of Ni microwires depended on the competition between Brownian motion and magnetic dipole moments from magnetic field. The larger nanoparticles with the higher magnetic moments preferred to form one-dimensional Ni microwires and their length increased up to several millimeters with the increasing magnetic field strength, while the average diameter of Ni microwires decreased. Furthermore, the easy magnetization direction of Ni microwires was parallel to the direction of magnetic field and the Ni microwires axis. [ABSTRACT FROM AUTHOR]

Our previous work revealed that in the pancreatic β cell line, geniposide modulated ATP production and glucose-stimulated insulin secretion (GSIS) induced by the acute stimulation of high glucose concentration. However, the effects of geniposide on functional impairment and the mass of β-cells exposed to elevated levels of glucose remains unknown. In the present study, impaired GSIS and restrained proliferation were observed in the prolonged culture of insulinoma INS-1 cells with 33 mM of glucose (high glucose). Our results indicate that the glucose-induced impairment of insulin release was significantly reverted by the inclusion of 1 or 10 μM of geniposide. Moreover, induction of the phosphorylation of AMP-activated protein kinase (AMPK) was observed, which promoted the utilization of nutrient stores for energy production. AMPK phosphorylation was enhanced by an increased number of INS-1 cells, and the increased expression of AMPK downstream target heme oxygenase 1 (HO-1), under high glucose concentration. Furthermore, geniposide protected rat insulinoma cells from apoptosis in high-glucose concentrations. We have shown that these effects were associated with an increased apoptosis-related Bcl-2/BAX protein ratio. In conclusion, geniposide dose dependently improves β-cell function and increases the proliferation of β-cells exposed to prolonged hyperglycemia. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of complete intermetallic joints rapidly formed by the ultrasonic-assisted transient liquid phase (TLP) soldering process were investigated. Compared to the intermetallic joints formed by the traditional TLP soldering process, the resulted intermetallic joints consisted of remarkably refined Cu 6 Sn 5 grains, with an average size of 3.5 μm. They also demonstrated more uniform mechanical properties with elastic modulus and hardness values of approximately 123 GPa and 6.0 GPa, respectively, as well as higher reliability, in terms of higher shear strength of 60.1 MPa. These results provided a new insight into the effects of ultrasonic on the microstructures and properties of intermetallic joints. [ABSTRACT FROM AUTHOR]

The non-interfacial growth of Cu 3 Sn intermetallic compounds (IMCs) in a Cu/Sn/Cu interconnection structure during the ultrasonic-assisted transient liquid phase (TLP) soldering process was investigated. In the traditional TLP soldering process, the Cu 3 Sn phase always nucleated at Cu 6 Sn 5 /Cu interfaces and grew at the expense of the Cu 6 Sn 5 phase and towards the joint centre, eventually forming a full intermetallic joint consisting of a single Cu 3 Sn phase with columnar grains. While in the ultrasonic-assisted TLP soldering process, the Cu 3 Sn phase nucleated and grew randomly within the whole joint, the resulting intermetallic joint consisted of a single Cu 3 Sn phase with equiaxed grains. This anomalous behaviour can be wholly ascribed to the effects ultrasonic on the nucleation and growth mechanisms of Cu 3 Sn. [ABSTRACT FROM AUTHOR]

The relationship between structure and mechanical, tribological and corrosion properties of coatings is investigated by adjusting the annealing time (750 °C for 1–10 h). Results exhibit that the coatings mainly consist of Ni(Mo) and Mo 2 C, and MoC is formed after long time annealing (≥4 h). The hardness of coatings decreases from 9.3 GPa to 5.9 GPa with the extension of annealing time, and the inversion relationship between strength and toughness (0.19–0.17) is observed owing to the decline of elastic recovery. The highest wear rate of coatings is about 13.6 × 10−6 mm3 N−1 m−1, and most of them under the applied load of 1.96 N and 3.92 N are in the range of 2.1–6.3 × 10−6 mm3 N−1 m−1. Meanwhile, the wear resistance of coatings annealed for 1–4 h is better than those annealed for longer time (6–10 h), and the change of it is proportional to the hardness and elasticity recovery. In addition, the corrosion resistance of coatings in 3.5 wt% NaCl solution decreases with annealing time due to the grain growth, the uneven distribution of composition and the increase of porosity. • Effect of structural changes on anti-wear and corrosion properties of coatings is studied. • Traditional inversion relation between strength and toughness is broken due to the graphitization of diamonds. • The wear mechanism of coatings is mainly abrasive. • Coatings with high hardness and elastic recovery has higher wear resistance. • Grain growth, uneven distribution of composition and increase of porosity lead to reduced corrosion resistance. [ABSTRACT FROM AUTHOR]

The unicellular freshwater green microalga Haematococcus pluvialis is the richest source of natural astaxanthin. Since accumulation of astaxanthin differs significantly among various algal strains at different stages, it is therefore critical to develop an effective high-throughput assay for rapid screening astaxanthin-hyperproducing strains. In the present study, near-infrared spectroscopy (NIRS) in combination with biochemical assay was employed for evaluation of the wide-type H. Pluvialis strains. The partial least squares (PLS) models of total biomass, astaxanthin content and astaxanthin expressed as a percentage of dry weight (DW) were developed with the R2 values as 0·959, 0·982 and 0·952, the prediction correlation factor ( r) values as 0·979, 0·988 and 0·966, and the residual predictive deviation (RPD) values as 4·88, 6·22 and 3·86, respectively. Furthermore, the PLS models were employed to evaluate H. pluvialis mutants, with the r values as 0·973, 0·983 and 0·976, and the RPD values as 3·45, 7·59 and 4·07, respectively. This work thus demonstrates that NIRS is an easy, fast and non-invasive approach that can be applied in high-throughput screening of astaxanthin-hyperproducing algal mutants. Significance and Impact of the Study Haematococcus pluvialis has potential application for its ability to accumulate natural antioxidant astaxanthin. In this study, we initiated the application of near-infrared spectroscopy (NIRS) in the analysis of total biomass and astaxanthin content of different mutant strains, demonstrating that NIRS can be very useful in the screening of axataxanthin-hyperproducing mutant strains. [ABSTRACT FROM AUTHOR]

The vertical distribution of suspended sediment in continental shelf waters has significant implications for water quality, aquatic ecology, and sediment transport. Nevertheless, there have been relatively few systematic field studies aimed at determining whether a general vertical trend in suspended sediment concentration (SSC) exists, or how any such vertical trend can be expressed mathematically. In this study, based on 402 individual SSC profiles measured hourly during 16 dual-tide voyages at 8 stations in the outer Yangtze Estuary, we found that SSC followed an average depth profile that was smoothly concave-up. This average profile, and the relationship between SSC and height above the seabed, was exponential ( R 2 >0.99). In comparison, the traditional Rouse equation based on hydrodynamics describes the measured average SSC profile poorly, in that the greater the distance from the near-bed height (where the reference SSC is taken), the greater the deviation of the simulated SSC from the measured SSC. However, in this study, a new approach was developed to overcome this flaw in the Rouse equation, which divides the equation into two parts. One part uses a reference SSC from a near-bed level, and an upwards decreasing coefficient, in the same way as the conventional Rouse equation. Conversely, the other part uses a reference SSC from at the water surface, and a downwards decreasing coefficient. Our modified hydrodynamics-based equation expresses the measured SSC well, with an R 2 between the simulated and measured SSCs exceeding 0.99. According to the average SSC profiles, the near-bed SSC was 2.8 times greater than the SSC at the water surface (close to the value of 3 suggested for modeling studies in the absence of empirical data), and the depth-averaged SSC was 1.8 times greater than the SSC at the water surface. We also found that the average SSC profile showed a uniform (from water surface to seabed) decline in SSC (25%) in response to the dramatic decline in the suspended sediment load supplied by the Yangtze River over the past three decades. However, the shape and vertical ratio of the average SSC profile have changed little, which suggests that the general form of the SSC profile is determined mainly by local hydrodynamics and sediment properties, and not by fluvial sediment supply. [ABSTRACT FROM AUTHOR]

Highlights: [•] Only stage III hardening occurs after yielding in Ti–6Al–4V/Ti17 dissimilar joints. [•] Voce stress and strength of the joints increase with increasing strain rate. [•] With increasing strain rate, hardening capacity and strain hardening exponent decrease. [•] With increasing temperature, hardening capacity and strain hardening exponent increase. [•] Strain rate sensitivity of the joints decreases as the true strain increases. [Copyright &y& Elsevier]

Abstract: Cyclic deformation characteristics of electron beam welded (EBWed) joints between Ti–6Al–4V and Ti17 (Ti–5Al–4Mo–4Cr–2Sn–2Zr) titanium alloys were evaluated via strain-controlled low-cycle fatigue tests at varying strain ratios at a constant strain amplitude. The welding led to a significant microstructural change across the dissimilar joint, with hexagonal close-packed (HCP) martensite α' and orthorhombic martensite αʺ in the fusion zone (FZ), α' in the heat-affected zone (HAZ) of Ti–6Al–4V side, and coarse β in the HAZ of Ti17 side. A distinctive asymmetrical hardness profile across the joint was observed with the highest hardness in the FZ and a lower hardness in the HAZ of Ti17 side than in the Ti17 base metal (BM), indicating the presence of soft zone. The strength and ductility of the dissimilar joint lay in-between those of two base metals (BMs). Unlike wrought magnesium alloys, the Ti–6Al–4V BM, Ti17 BM, and joint basically exhibited symmetrical hysteresis loops in tension and compression in the fully reversed strain-controlled tests at a strain ratio of R ε =−1. At a strain ratio of R ε =0 and 0.5, a large amount of plastic deformation occurred in the ascending phase of the first cycle of hysteresis loops of Ti–6Al–4V BM, Ti17 BM, and joint due to the high positive mean strain values. Fatigue life of the joint was observed to be the longest at R ε =−1, and it decreased as the strain ratio deviated from R ε =−1. A certain degree of mean stress relaxation was observed in the non-fully reversed strain controlled tests (i.e., R ε ≠−1). Fatigue failure of the dissimilar joints occurred in the Ti–6Al–4V BM, with crack initiation from the specimen surface or near-surface defect and crack propagation characterized by fatigue striations. [Copyright &y& Elsevier]

Abstract: The microstructure, hardness, tensile and fatigue properties of electron beam welded dissimilar joints between Ti–6Al–4V and BT9 (Ti–6.5Al–3.5Mo–1.5Zr–0.3Si) titanium alloys were studied. A marked microstructural change occurred after welding, with martensite in the fusion zone (FZ) and in the heat-affected zone (HAZ) of Ti–6Al–4V side, and martensite plus some retained α phase in the HAZ of BT9 side. While an asymmetrical hardness profile across the dissimilar joint was observed with significantly higher hardness values in the FZ, no soft zone was present in the HAZ of the Ti–6Al–4V/BT9 dissimilar joints. The ultimate tensile strength, monotonic and cyclic yield strength, and cyclic strain hardening exponent of the dissimilar joints lay in-between those of two base metals (BMs). The joint and BMs had almost the same monotonic and cyclic stress–strain curves and fatigue life, while the cyclic strain hardening exponent was slightly higher than the monotonic strain hardening exponent. Although cyclic softening occurred at higher strain amplitudes, cyclic stabilization appeared at lower strain amplitudes up to 0.6% for both BMs and joints. Fatigue failure of the dissimilar joints occurred in the BM of Ti–6Al–4V, with crack initiation from the specimen surface or near-surface defect and crack propagation characterized by fatigue striations along with secondary cracks. [Copyright &y& Elsevier]

Abstract: The aim of this study was to evaluate the microstructure, hardness and cyclic deformation behavior of electron beam welded dissimilar joints of Ti–6Al–4V and Ti17 (Ti–5Al–4Mo–4Cr–2Sn–2Zr) titanium alloys. The welding resulted in a significant microstructural change across the joint, with hexagonal close-packed (hcp) martensite α′ and orthorhombic martensite α″ in the fusion zone (FZ), α′ in the heat-affected zone (HAZ) of Ti–6Al–4V side, and coarse β in the HAZ of Ti17 side. A characteristic asymmetrical hardness profile across the dissimilar joint was observed with the highest hardness in the FZ and a lower hardness on the Ti–6Al–4V side than on the Ti17 side, where a soft zone was observed. The dissimilar joint exhibited a lower Young′s modulus and higher cyclic strain hardening exponent than both Ti–6Al–4V and Ti17 base metals (BMs), and had the monotonic and cyclic yield strengths lying in-between those of two BMs with higher values for Ti17 alloy. Both BMs and joint showed essentially symmetrical hysteresis loops and equivalent fatigue life, and exhibited cyclic stabilization at lower strain amplitudes up to 0.6%, while cyclic softening occurred after initial cyclic stabilization at higher strain amplitudes. The initial cyclic stabilization was shortened with increasing strain amplitude. In the Ti–6Al–4V BM fatigued at a high strain amplitude of 1.2%, a short initial cyclic hardening emerged, corresponding to the presence of twinning and its resistance to the dislocation movement. Fatigue failure of the dissimilar joint occurred in the HAZ of Ti17 side where the soft zone was present, with crack initiation from the specimen surface or near-surface defect and crack propagation characterized by typical fatigue striations. [Copyright &y& Elsevier]

Abstract: Microstructures, tensile properties and strain hardening behavior of a friction stir welded (FSWed) thick AA2219 aluminum alloy under optimized welding parameters and varying cooling conditions (air cooling and water cooling) were investigated with three slices (top, middle and bottom) through the plate thickness. While the yield strength was lower in the FSWed joints than in the base metal, the ultimate tensile strength of the FSWed joints with water cooling reached nearly that of the base metal. In particular, FSW resulted in a significant improvement in the ductility of the alloy due to the presence of recrystallized fine grains with fragmented and uniformly dispersed second-phase particles in the weld nugget zone. Water cooling resulted in both higher strength and ductility, but lower strain hardening capacity than that with air cooling during FSW. Compared with the middle and bottom slices, the top slice had a higher strength, but lower ductility and strain hardening capacity. While stages III and IV hardening occurred after yielding in both base metal and FSWed samples, the FSW led to higher hardening capacity and strain hardening rate and exponent mainly in the middle and bottom slices. The fracture surfaces after FSW exhibited more obvious ductile fracture characteristics with dimples and tearing ridges along with micropores. [Copyright &y& Elsevier]

Abstract: Dehumidifier is the core component in a liquid desiccant air-conditioning system, whose efficiency directly affects the whole performance. In this study a cross-flow dehumidifier was established in which LiCl solution and Celdek structured packing were used. Enthalpy efficiency and moisture efficiency were adopted to describe the heat and mass transfer performance of the dehumidifier. Influence of desiccant and air inlet parameters on the dehumidifier performance was experimentally investigated, and efficiency comparison in different air outlet regions was also carried out, as well as influence of packing structure size on dehumidifier performance. The results show that the outlet parameter values of air and solution can be easily gained with enthalpy efficiency and moisture efficiency which was obtained from experimental regression. Efficiency has obvious regional characteristics. By increasing the thickness, width or height simultaneously, better performance of Dehumidifier can be achieved without increasing the pressure loss. [Copyright &y& Elsevier]

The microstructure and cyclic deformation behavior of three slices of a thick plate of friction-stir-welded Al–Cu alloy were investigated. Friction stir welding resulted in a composite-like nugget zone consisting of fine particles uniformly dispersed in the recrystallized fine-grained matrix. The top slice had larger grains, smaller particles, higher hardness, stronger cyclic hardening, higher hysteresis energy and lower fatigue life than the bottom slice. Fatigue cracks initiated from near-surface particles in the low-hardness zone, and propagated via striation formation mechanisms along with particle cracking. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this study was to reveal the material flow and temperature distribution in a thick aluminum plate during friction stir welding and examine the subsequent microstructural change with particular attention to the reaction between copper marker and aluminum matrix. It is shown that the material adjacent to the threaded pin was transported from the top to bottom non-symmetrically, and then was forced to move upwards at a small distance from the pin due to the constraint of an extrusion-die-like configuration. The interaction between the copper marker and aluminum matrix led to the formation of (i) a unique core/multi-shell microstructure consisting of copper core, inner shell of AlCu and outer shell of Al2Cu, and (ii) a composite band containing uniformly-distributed Al2Cu particles with refined grains due to the lower stacking fault energy of copper and the pinning role of Al2Cu particles. [Copyright &y& Elsevier]

Abstract: Effects of gas pressure and plasma power on the growth of carbon-based nanostructures (CNSs) have been studied in detail. Multi-walled carbon nanotube (MWCNTs) and carbon nanowalls (CNWs) were synthesized on glass substrates via radio frequency plasma-enhanced chemical vapor deposition (RFPECVD) technique. Surface morphologies of the films have been studied by SEM and TEM. When the gas pressure increases from 120 to 300Pa, the deposited carbon material changes from MWCNTs to carbon nanowalls (CNWs). Additionally, the density of carbon nanostructures increases with the gas pressure. The radio frequency (RF) plasma power ranging from 600 to 2400W was applied during the activation and deposition process. The plasma enhances the decomposition of carbon atoms to deposit onto the surfaces of catalyst particles. Whereas an exorbitant RF plasma power can destroy the already deposited carbon nanostructures. [Copyright &y& Elsevier]

Aims: Dwarf bunt of wheat, caused by Tilletia controversa Kühn, is a destructive disease on wheat as well as an important international quarantined disease in many countries. The objective of this investigation was to develop a diagnostic molecular marker generated from amplified fragment length polymorphism (AFLP) for rapid identification of T. controversa. Methods and Results: A total of 30 primer combinations were tested by AFLP to detect DNA polymorphisms between T. controversa and related species. The primer combination E08/M02 generated a polymorphic pattern displaying a 451-bp DNA fragment specific for T. controversa. The marker was converted into a sequence-characterized amplified region (SCAR), and specific primers (SC-0149/SC-02415), designed for use in PCR detection assays, amplified a unique DNA fragment in all isolates of T. controversa, but not in the related pathogens. The detection limit with the primer set SC-0149/SC-02415 was 10 ng of DNA which could be obtained from 11 μg of teliospores in a 25- μl PCR reaction. Conclusions: An approach to distinguish T. controversa from similar pathogenic fungi has been developed based on the use of a SCAR marker. Significance and Impact of the Study: Development of the simple, high throughput assay kit for the rapid diagnosis of dwarf bunt of wheat and detection of T. controversa is anticipated in further studies. [ABSTRACT FROM AUTHOR]

Abstract: Multi-walled carbon nanotubes (CNTs) were synthesized on the surfaces of Ni-alloy plated Fe-wires with the diameter of 2mm using a conventional laboratory ethanol (C2H5OH) flame method at 560°C. SEM showed that the product had bush-shaped micron-structures with diameters from 100 to 450nm and lengths of over 1.0μm. TEM revealed that the micron-structures were composed of multi-walled nanotube bundles with the diameters of about 50nm. The test on the diode configuration field emission of the Fe-wire arrays was performed. The onset electric field was 2.95V/μm and the emission current can reach 50mA/cm2 at an electric field of 9V/μm. The average fluctuation of the emission current density was less than 7%. The result suggests that the field emission was uniform and the present technique was feasible to fabricate Panel Field Emission Lamp (PFEL) with arrays of carbon nanotubes. PFEL has the advantages of high luminescence as well as stability, and thus, it can be used to replace ordinary lights. [Copyright &y& Elsevier]

[Display omitted] • Co 2 Z hexaferrites and FeSiCrB powders are compacted into toroidal Co 2 Z/FeSiCrB SMCs. • Air gaps between FeSiCrB powders are filled with Co 2 Z hexaferrites. • Co 2 Z hexaferrites increases the density of Co 2 Z/FeSiCrB SMCs and reduce Hc. • Co 2 Z hexaferrites increases conduction area and decreases demagnetization effect. • Co 2 Z/FeSiCrB SMCs possess the higher permeability and lower core loss than FeSiCrB SMCs. Z-type Sr 3 Co 2 Fe 24 O 41 hexaferrites (Co 2 Z hexaferrites) were synthesized with sol–gel method and were mechanically mixed with spherical Fe 88 Si 7 Cr 2.5 B 2.5 (FeSiCrB) amorphous powders, and then compacted to form toroidal Co 2 Z hexaferrites/FeSiCrB amorphous soft magnetic composites (Co 2 Z/FeSiCrB SMCs). The compositions, morphology and soft magnetic performance were characterized through SEM, XRD, VSM, EDS, B-H analyzer and impedance analyzer. All results reveal that Co 2 Z hexaferrites in Co 2 Z/FeSiCrB SMCs should mainly exist in air gaps between spherical FeSiCrB amorphous powders, leading to the increasing density. Saturation magnetization decreases a little for magnetic dilution and coercivity increases for the stronger magnetic interaction of Co 2 Z/FeSiCrB SMCs. The introduction of Co 2 Z hexaferrites in air gaps increases the conduction area of magnetic circuits and decreases the demagnetization effect, leading to the higher effective permeability of 27.4 for Co 2 Z/FeSiCrB SMCs, much higher than 25.0 for FeSiCrB SMCs. Furthermore, Co 2 Z/FeSiCrB SMCs present the smaller core loss and more stable DC bias characteristics owing to the insulating Co 2 Z hexaferrites. [ABSTRACT FROM AUTHOR]

Abstract: The damage and fracture behaviors of high purity polycrystalline zinc with two grain sizes during tension were investigated experimentally at different strain rates. It was found that specimens with coarse grains (∼1mm) showed serrated flow behavior and failed in intermittent brittle cleavage fracture, while specimens with fine grains (∼70μm) showed no cleavage crack initiation before necking even at high strain rate. It was observed that the fracture process of the fine-grained specimen was highly related to strain rates. With the strain rate increasing, the damage mechanism transformed from formation of tearing cracks along interfaces (including grain boundaries, twin boundaries and kink band boundaries) and cavity coalescence into abrupt quasi-cleavage fracture. Based on the observation, the inter-crystalline fracture of zinc was investigated, and the damage and fracture behaviors of polycrystalline zinc during tension at room temperature were discussed in general. [Copyright &y& Elsevier]

Abstract: We observationally deduce the inductive electric field in the photosphere for the first time from the horizontal velocities computed by local correlation tracking (LCT) technique and the vector magnetic fields derived from vector magnetograms. We study the relationship between E and powerful flares (X-class) of four active regions (ARs): NOAA 10720, 10486, 9077 and 8100. It is found that the kernels of flares are roughly located near the inversion lines where maxima of E are observed. Our results show that E relates to the accumulation of non-potentiality in the photosphere and the transportation of non-potentiality from the photosphere to the corona. [Copyright &y& Elsevier]

Abstract: Silicon wafers are the most widely used substrates for fabricating integrated circuits. There have been continuous demands for higher quality silicon wafers with lower prices, and it becomes more and more difficult to meet these demands using current manufacturing processes. In recent years, research has been done on electrolytic in-process dressing (ELID) grinding of silicon wafers to explore its potential to become a viable manufacturing process. This paper reviews the literature on ELID grinding, covering its set-ups, wheel dressing mechanism, and experimental results. It also discusses the technical barriers that have to be overcome before ELID grinding can be used in manufacturing. [Copyright &y& Elsevier]

Abstract: Many more attempts have been made to develop new powder materials to fabricate metal objects via indirect SLS process. Unfortunately, current attention still focuses on singular alloy powders, which has confined the development of indirect SLS. Hence composite elemental powders (CEPS) of Fe–Cu–C system and Fe–Cu–Ni–C system are selected and obtained by briefly blending iron, copper, nickel, graphite and polymer binder powders in this study. Green shapes composed of aforementioned polymer bonded CEPS were formed via indirect SLS process firstly. Then full density hybrid alloys composed of Fe–Cu–C or Fe–Cu–Ni–C system alloys and copper were manufactured after the green shapes had been decomposed at 900°C, sintered at 1200°C, infiltrated at 1200°C with molten copper and thermally treated. Some aspects of the SLS forming process and post process were discussed. The microstructures and the mechanical properties of sample alloys were investigated either. The bending strength of metal green shapes is 2.41MPa; the binder material decomposes almost entirely below 900°C; copper, nickel and graphite can diffuse into γ-Fe and distribute uniformly after sintering and infiltration process; quenched at different temperatures over 900°C and tempered at 200°C, the copper infiltrated alloys have a yield strength over 400MPa and a elongation under 3%; compared to that of other alloys, the mechanical properties of hybrid alloy composed of Fe–8Cu–4Ni–0.5C alloy and copper are better. Hence CEPS can be used to manufacture metal parts via indirect SLS process, which is also an additional contribution to SLS. [Copyright &y& Elsevier]

Abstract: The transition between rubbing and cutting when a facet-first pyramid is slid along the surface of a ductile material is investigated with new experiments under both constant depth of groove and constant load, and with a new ductile fracture mechanics analysis for the cutting regime. The critical attack angle at which the transition occurs is shown to be controlled by the toughness/strength (R/τ y ) ratio of the material, the depth of groove, friction and the face angle of the tool. The new analysis is contrasted with the Bowden and Tabor approach in Sedriks and Mulhearn [A.J. Sedriks, T.O. Mulhearn, Mechanics of cutting and rubbing in simulated abrasive processes, Wear 6 (1963) 457–466; A.J. Sedriks, T.O. Mulhearn, The effect of work-hardening on the mechanics of cutting in simulated abrasive processes, Wear 7 (1964) 451–459] and with other approaches for the same events, and it explains why certain assumptions in Sedriks and Mulhearn can be justified. The analysis shows that the vertical load during sliding is different from that required for indentation to the same depth below the surface. Consequently the depth of the groove during sliding under deadweight loading is different from the depth resulting from initial indentation. At very small attack angles, the depth can be smaller than the static indentation depth, but as the attack angle increases, so does the depth of groove formed by cutting. The relevance of the model to abrasive wear and polishing is discussed, along with implications for Krushschov–Babichev wear resistance diagrams and the Archard equation. The analysis explains why the specific energy in grinding increases at small depths of cut. Measurement of the critical attack angle in scratching with a facet-first indenter may possibly be a way to estimate the fracture toughness of small samples when other, more conventional, methods are difficult to carry out. [Copyright &y& Elsevier]

Abstract: Grinding is an important process for manufacturing of silicon wafers. The demand for silicon wafers with better quality and lower price presents tremendous challenges for the grinding wheels used in the silicon wafer industry. The stringent requirements for these grinding wheels include low damage on ground surfaces, self-dressing ability, consistent performance, long wheel lives, and low prices. This paper presents a literature review on grinding wheels for manufacturing of silicon wafers. It discusses recent development in abrasives, bond materials, porosity formation, and geometry design of the grinding wheels to meet the stringent requirements. [Copyright &y& Elsevier]

A quasi-static analysis is presented in this paper for in-service pressurised pipelines subjected to an external impact. Based on the assumed simple rigid, perfectly plastic deformation model, a simple relationship is obtained between the external denting force F and the maximum dent depth δ0. Results from the theoretical analysis are in reasonable agreement with results from finite element analyses. These show that the pressure p=pin-pout has a large influence on the pipe resistance to the indentation, where pin and pout are the internal and external pressure, respectively. For the same dent depth, a higher external denting force is required for pipes with higher pressure, p. The difference of the required force between a lowly pressurised pipe and a highly pressurised pipe increases with increasing denting depth. [Copyright &y& Elsevier]

The damage characteristics of ferrite nodular cast iron under uniaxial stress were evaluated by measuring electric resistance. The results showed that the damage within the matrix of nodular cast iron occurred when the applied stress exceeds the damage threshold, and the damage variable for describing the damaged state of materials increases with stress. The evolutional law of damage variable as a function of stress was founded. The damage threshold of nodular cast iron increases with nodularity, but it is lower than yield strength. In addition, the critical damage variable is not related to the nodularity, which is about 0.06–0.068. [Copyright &y& Elsevier]

In the present study, using a rat pheochromocytoma (PC12) cell line, the effect of catalpol on H2O2-induced apoptosis was studied. The apoptosis in H2O2-induced PC12 cells was accompanied by down-regulation of Bcl-2, up-regulation of Bax, the release of mitochondrial cytochrome c to cytosol and sequential activation of caspase-1 and caspase-3 then leading to cleavage of poly-ADP-ribose polymerase (PARP). Catalpol not only suppressed the down-regulation of Bcl-2, up-regulation of Bax and the release of mitochondrial cytochrome c to cytosol, but also attenuated caspase-3 activation, PARP cleavage, and eventually protected against H2O2-induced apoptosis. Taken together, these results suggest that treatment of PC12 cells with catalpol can block H2O2-induced apoptosis by the regulation of Bcl-2 family members, as well as suppression of cytochrome c release and caspase cascade activation. [Copyright &y& Elsevier]

Separation of metal ion complex, [(C12H8N2)3Fe2+], with surfactant sodium dodecylphrate (DLS) complex from aqueous phase was carried out by solvent sublation, which obeys first-order kinetics. On the base of the complete transport mechanisms, the Langmuir adsorption, and the ion complex equilibrium in the aqueous phase, a mathematical model for the [(C12H8N2)3Fe2+]–surfactant ion complex is obtained with the aid of the Mathematic 4.0 program, 4th Runge–Kutta method, and the Matlab programs. The effects of many parameters, such as Ka, Kl, Kow, di, Vo, Vw, and Qa, on solvent sublation are investigated. Furthermore, the simulation showed that the model is substantiated for experiments on the solvent sublation of the complex. [Copyright &y& Elsevier]

In this paper, based on the establishment of a reasonable mechanics model for a typical draw-spinning, research on the first pass of the spinning process is carried out with an elasto-plastic FEM method. The distributions of the stress and strain are obtained under three types of roller-trace curves: straight lines, involute curves and quadratic curves. The distribution laws of the radial and tangential stress that are obtained can serve as a significant guide to determining the forming limits in multi-pass conventional spinning under different roller-traces. Comparison of the distributions of strain and stress of three roller-traces could provide a theoretical basis for selecting a reasonable roller-trace in multi-pass conventional spinning. [Copyright &y& Elsevier]

• Co 2 Z-type hexaferrites are well dispersed in iron-based soft magnetic composites (SMCs). • Fe/Co 2 Z SMCs possess the high Ms and low Hc than the pristine Fe SMCs. • Fe/Co 2 Z SMCs present the higher effective permeability, lower core loss at high frequency. • Fe/Co 2 Z SMCs show the more stable D-C bias characteristics than the pristine Fe SMCs. • Co 2 Z hexaferrites could effectively improve the high-frequency performance of Fe/Co 2 Z SMCs. Co 2 Z-type hexaferrites were synthesized with sol–gel method, and then were composited with pure iron powders to form a new type of iron-based soft magnetic composites (SMCs). The morphology, components and magnetic properties of all samples were characterized by XRD, SEM, EDS, B-H Analyzer and DC Current Source. All results indicate that Co 2 Z-type hexaferrites are well dispersed in the SMCs and play the role of insulation. Fe/Co 2 Z SMCs with the high Ms and low Hc present the higher effective permeability, lower core loss at high frequencies and more stable D-C bias characteristics than the pristine Fe SMCs. All results indicate that Co 2 Z hexaferrites with the high resistance could effectively improve the high-frequency performance of Fe/Co 2 Z SMCs. [ABSTRACT FROM AUTHOR]

Examines the plight of the Chinese white dolphin, Sousa chinensis, and its implication for environmental policy making in Hong Kong. Trade-offs between environmental protection and economic development; Focus on the environmental effects of the development of Chek Lap Kok airport; Assessment of environmental policy process.

• A submodeling method was proposed to simulate the local stress near the interfacial asperity of coatings. • Global mechanical analysis of a vane with TBCs was studied. • Submodel was established with asperity and divided into three unique zones with proper mesh density according to functions. • Submodeling analysis was separately processed but the boundary conditions was prescribed from the results of global analysis. Modeling the residual stress of TBCs near the interfacial asperity on turbine component tends to encounter numerical cumbersomeness ordinarily due to huge computational scale and complex mechanical behavior. This paper proposed a numerical method named submodeling method to simulate the local stress near the asperity by a partition model (named submodel) of a coated vane, based on the submodeling technique of ABAQUS code. First a global mechanical analysis about the coated vane was carried lasting three thermal cycles without considering interface asperities. Then a submodel was established with asperity and divided into three unique zones with proper mesh density according to their functions. Finally the local mechanical analysis was separately processed by submodeling method, based on interpolation of the solution from the global analysis onto the outer zone of the submodel. The results show that the stress level of TC near the asperity is relatively low after 3 thermal cycles. The normal stress and the shear stress of BC near the asperity are concentrated in the peak and nearby the trough, respectively. These stress concentrations may lead to TGO/BC interfacial crack. The stress values and distribution feature of BC near the asperity is quite agreement with former results. These may prove that submodeling method can be applicable for local stress modeling and failure prediction. [ABSTRACT FROM AUTHOR]

• Diamond/matrix interface of composite annealed at 450 °C becomes wide. • Graphitization of diamonds and precipitation of Mo 2 C are detected at 750 °C. • Traditional Archard model is broken due to the lubrication of Mo 2 C and the increase in elasticity. • Composite with wide diamond/matrix interfaces has the lowest corrosion resistance. • Precipitation of MoNi and Mo 2 C improves the corrosion resistance of composites. Ni–18 at.% Mo/21 vol% diamond composites are prepared on steel substrates by electrodeposition. Influence of annealing temperature (450–750 °C) on the microstructure, phase composition, hardness, tribological properties and corrosion resistance of composites is analyzed. Results show that matrix grain grows from 7 nm to 38.4 nm with the increasing temperature. Wide and amorphous particle/matrix (P/M) interface is observed at 450 °C due to Mo segregation, improving hardness (11.3 GPa) and wear resistance of composites. However, the uneven distribution of composition at P/M interface leads to the occurrence of local corrosion and the reduction of corrosion resistance. MoNi and Mo 2 C intermetallics are precipitated in composites while the temperature is ≥480 °C and 681 °C, respectively. Phase transition decreases Mo segregation at P/M interface and causes the disappearance of amorphous P/M interface, which inhibits local corrosion and improves corrosion resistance. Meanwhile, the consumption of Mo, the graphitization of diamonds and the growth of grains cause the softening of composites. However, composite annealed at 750 °C with the lowest hardness (6.2 GPa) has the lowest wear rate (3.4 × 10−6 mm3 N−1 m−1), which breaks the traditional Archard model attributing to the lubrication of Mo 2 C. [ABSTRACT FROM AUTHOR]

Ni Mo alloys with various Mo contents are prepared by electrodeposition in sulfate–citrate acid solutions under different temperature, pH, stirring rate, current density and MoO 4 2− concentration. Influences of Mo content on the grain size, hardness and wear resistance are studied. Results show that the increase in Mo content decreases the deposition rate of Ni Mo alloys prepared at a constant temperature. As–prepared alloys are composed of nanocrystalline Ni(Mo) solid solution when Mo is less than 24.4 at.%. The grain size of alloys decreases with the increment of Mo content. Amorphous phase appears in deposits when Mo content exceeds 24.4–27.3 at.%. Hardness and wear resistance of alloys firstly increases with Mo content, and then it has a decline due to the formation of amorphous. Additionally, Hall–Petch (HP) relationship is found in deposits as the grain size decreases from 12.4 nm to 7.9 nm, and then the inverse HP relationship appears with the further decrease in grain size to 1.5 nm. Meanwhile, traditional Archard law is found in Ni Mo alloys with Mo content in the range of 6.3–27.3 at.%. Additionally, HP breakdown causes a variation of wear resistance at the critical grain size of 7.9 nm. • Nanocrystalline and amorphous Ni–Mo alloys are obtained at different experimental conditions. • Plastic deformation of nanocrystalline Ni–Mo alloys is mediated by GBs. • Hall–Petch and its inverse relations are obtained in Ni–Mo alloys. • Critical grain size of Hall–Petch breakdown is 7.9 nm, smaller than that in pure Ni. • Hall–Petch breakdown is manifested in a variation of wear resistance in Ni–Mo alloys. [ABSTRACT FROM AUTHOR]

Ni-Mo coating with different Mo content is prepared by electrodeposition. The influences of Mo content and heat treatment on the structure, hardness, and wear and corrosion properties of coatings are studied. It is found that Ni-Mo coatings consist of nanocrystalline, and the grain size is ≤18.5 nm. MoNi intermetallic precipitates out when the annealing temperature is ≥ 499 °C. Both of the Mo content and the heat treatment are important to strengthen coatings. The highest hardness is about 10.3 GPa, corresponding to the Ni–19.1 at.% Mo coating after annealing at 500 °C. The lowest wear rate is about 2.1 × 10−4 mm3 N−1 m−1, which related to Ni–22 at.% Mo coating annealed at 450 °C. Additionally, Ni–16.7 at.% Mo coating after annealing at 450 °C shows the best corrosion resistance in 0.5 M H 2 SO 4. • Electrodeposited Ni–Mo coatings consist of nanocrystalline. • MoNi intermetallic precipitates out when the annealing temperature is ≥499 °C. • Optimum Mo content and heat treatment are important to strengthen coatings. • Wear resistance of Ni–Mo coatings increases with hardness. • Optimum Mo content for highest corrosion resistance behavior was obtained. [ABSTRACT FROM AUTHOR]

Ni–Mo/diamond composite coatings have been electrodeposited in a Ni–Mo electrolyte containing micron diamonds with five different sizes, respectively. The diamond content in coatings is in the range of 5–31 vol%. The grain size of as-annealed coatings is smaller than 10 nm. Microhardness of as-annealed coatings increases with the diamond content, and the highest hardness is about 15.4 GPa. The as-annealed coatings incorporated with 5 μm diamonds have supvderior wear resistance to that of the other coatings. The lowest wear rates of the as-annealed coating and the pin-on-disk system are about 2 × 10−6 and 5 × 10−6 mm3 N−1 m−1, respectively, which all correspond to the coating containing 31 vol% diamonds with the size of 5 μm. • Ni–Mo/micron diamond composite coating was prepared by electrodeposition. • Microhardness of the composite coatings increases with diamond content. • High diamond size and content are helpful improving the tribological performance of coatings. [ABSTRACT FROM AUTHOR]

Ni Mo/diamond composite coatings were electrodeposited on stainless steel from a plating bath containing micron-sized diamond particles. Effects of electrodeposition parameters on the composition, microstructure, mechanical properties and corrosion resistance are studied. Results show that the chemical composition of coatings strongly depends on the selection of electrodeposition parameters. The Ni Mo matrix of coatings consisted of Ni(Mo) solid solution with ultrafine nanograins. The hardness of coatings was enhanced by adding diamonds and annealing treatment, and the highest hardness was about 11.3 GPa. Meanwhile, the wear rate of composite coatings was at least about 1/6 of that for Ni Mo coating. Furthermore, the corrosion resistance of coatings in 3.5 wt% NaCl solution was slightly decreased due to the micro-galvanic cells between the matrix and diamonds. • Ni-Mo/diamond composite coating was prepared on stainless steel by electrodeposition. • Ni-Mo matrix metal consisted of Ni(Mo) solid solution with ultrafine nanograins. • The hardness of coatings was improved after adding diamonds and annealing. • Diamonds in the coatings were helpful to improve the wear resistance of coatings. • The corrosion resistance of coatings was slightly decreased by adding diamonds. [ABSTRACT FROM AUTHOR]

Fretting is the small amplitude relative oscillatory motion between two solid contact surfaces. Many factors would make impacts on the fretting process, the body stress and contact pressure can be regarded as two major independent factors resulting in the fretting fatigue. The effects of torque and contact pressure on torsional fretting behavior of 316 L austenitic stainless steel are studied in a cylinder-on-cylinder contact configuration. The results indicate that torsional fatigue life drops rapidly due to fretting. The S-N curves of torsional fretting fatigue show a shape of “ C ”. Along with increasing the contact pressures, the fretting fatigue life decreases and enters to a platform area. The variety law of friction coefficient under different contact pressures is obtained. Both fatigue fracture and fretting scar are analyzed with SEM, EDX, XPS and three-dimensional white light interferometer (3D). The study shows that the torsional fretting fatigue is influenced by fretting running behavior. Meanwhile, the depth of crack initiation position would also be affected by contact pressure. In this paper, we proposed the failure mechanisms of the fretting zone, including plastic deformation, delamination, plow and oxidative wear. [ABSTRACT FROM AUTHOR]

Introduction: Most quality of care studies that have analyzed administrative databases have only been able to examine inpatient mortality—which may be a limitation for procedures whose inpatient mortality rates are low. In response, some researchers have examined longer term mortality outcomes (e.g. 30-day), but the available databases only pertain to non-representative segments of the population (i.e. Medicare patients, or Veterans), or cancer registries. In this study, we use a newly developed database to examine the 1-year mortality rates for two vascular surgery procedures. Importantly, the data is population-based, and therefore generalizable. Methods: The OSHPD database (1995–1999), which reports all California inpatient discharges, was linked to the State Death File in order to study mortality outcomes beyond hospital discharge. CEA and AAA procedures were identified by ICD-9 codes and the rates of inpatient and 1-year mortality were assessed. Analyses were performed for each procedure, as well as for elective and emergent cases. Results: For all CEA procedures (n = 44601), the inpatient and 1-year mortality rates were 0.8% and 5.8%, respectively. For emergent cases, the inpatient and 1-year mortality rates were 1.57% and 9.19% (which represents a 5.8-fold increase), while that for elective cases were 0.5% and 5.4% (a 9.7-fold increase). Finally, the CEA inpatient mortality rate for all patients accounts for only 14% of all CEA deaths at 1 year. For all AAA procedures, (n = 16114), the inpatient and 1-year mortality rates were 12.8% and 18.8%. The inpatient and 1-year mortality rates for emergent cases were 28% and 37.1% (a 1.3-fold increase), while for elective cases, they were 4.5% and 9.7%, respectively (a 2.15-fold increase). Contrary to CEA procedures, the AAA inpatient mortality rate for all-comers accounts for 68% of the AAA deaths at 1 year. Conclusions: Our study uses a novel database linkage and reports inpatient and 1-year mortality rates for two common vascular surgical procedures (i.e. CEA and AAA). This analysis provides meaningful data because of the ability to examine outcomes beyond hospital discharge. Future studies will examine the longer-term mortality rates of other common surgical procedures. [Copyright &y& Elsevier]