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Abstract: In order to reveal the high-velocity deformation mechanisms of 5052 aluminum alloy sheets, this work compares the dynamic plastic deformation behavior and the microstructure evolutions with those of the quasi-static case by scanning electron microscopy (SEM) observations, electron back scattering diffraction (EBSD) analysis, and transmission electron microscopy (TEM) studies. Results show that the dynamic process exhibits a very different macro fracture shape and a much similar micro deformation pattern as compared with the quasi-static case, and under both conditions, the dislocation-slip mechanism works during deformation. For the shock effect of high-velocity deformation, much denser dislocations are generated and the tendency of cross-slip of dislocations increases. The dislocation bands are more narrow and denser than those shown in the quasi-static case, and a much more uniform dislocation configuration is also exhibited after dynamic loadings. In addition, under dynamic conditions, the existing of pre-strain will introduce an accommodated effect on the dynamically induced dislocations, a slight reduction of density combining with a higher movement tendency. The characteristics of multi-slips and homogenization effect of dislocations under dynamic conditions will result in much higher plasticity and strength of materials over the quasi-static ones. [Copyright &y& Elsevier]

Abstract: This work develops a prototype 20W portable DMFC by system integration of stack, condenser, methanol sensor-less control and start-up characteristics. The effects of these key components and control schemes on the performance are also discussed. To expedite the use of portable DMFC in electronic applications, the system utilizes a novel methanol sensor-less control method, providing improved fuel efficiency, durability, miniaturization and cost reduction. The operating characteristics of the DMFC stack are applied to control the fuel ejection time and period, enabling the system to continue operating even when the MEAs of the stack are deteriorated. The portable system is also designed with several features including water balance and quick start-up (in 5min). Notably, the proposed system using methanol sensor-less control with injection of pure methanol can power the DVD player and notebook PC. The system specific energy and energy density following three days of operation are 362Whkg−1 and 335WhL−1, respectively, which are better than those of lithium batteries (∼150Whkg−1 and ∼250WhL−). This good energy storage feature demonstrates that the portable DMFC is likely to be valuable in computer, communication and consumer electronic (3C) markets. [Copyright &y& Elsevier]

Abstract: ZnO nanostructures have been grown on p-type Si(100) and glass substrates by thermal evaporating pure zinc powder without any metal catalysts at 450 or 480°C. The microstructures of the samples under SEM show nanowires, nanorods and feathers-like morphologies. XRD reveals a preferred orientation of the well-aligned nanorods grown on silicon substrates at 480°C. And all kinds of grown nanostructural samples are hexagonal ZnO crystal. The growth mechanism of synthesized nanostructures is discussed. Temperature and substrate are critical experimental parameters for the formation of different morphologies of ZnO nanostructures. Room-temperature photoluminescence spectrum of the well-aligned nanorods shows a blue emission band at 420 and 444nm. The blue luminescence is due to the electrons transition from the shallow donor levels of oxygen vacancies to the valence band. [Copyright &y& Elsevier]

1D-nanostructural zinc oxide (ZnO) with different shapes have been synthesized on p-type Si(1 0 0) and glass substrates via vapor phase growth by heating pure zinc powder at temperatures between 480 and 570 °C. The different ZnO nanostructures depend on the substrates and the growth temperatures. Scanning electron microscopy and X-ray diffraction revealed that a well-aligned nanowires array, which are vertical to the substrate of Si(1 0 0) with 18 sides on their heads, but six sides on their stems, has been formed at 480 °C. Raman study on the ZnO nanostructures shows that the coupling strength between electron and phonon determined by the ratio of the second- to the first-order Raman scattering cross-sections declines with decreasing diameter of the nanowires. However, a little changes of the coupling strength in terms of the width of the nanobelts have been observed. [Copyright &y& Elsevier]

We report a case study carried out on Lower Ordovician reservoir carbonates of the Lunnan Low Uplift, Tarim Basin, to determine trapping pressures and temperatures of petroleum inclusions from the intersection of isochores of coeval petroleum and aqueous fluid inclusions using PVT SIM software. There are four types of petroleum inclusions from this sequence. Their trapping pressures and temperatures are: Type I 80–105 °C, 199–230 bar; Type II 135–145 °C, 235–250 bar; Type III 155–165 °C, 344–360 bar, and Type IV 220–252 °C, 345–390 bar, respectively, which are consistently higher than their homogenization temperature and saturation pressures by about 5–15 °C and 25–70 bar. To confirm the reliability of the PVT simulation approach, fluid inclusions were synthesized in calcite under controlled temperature and pressure conditions and studied using the same methods. The calculated trapping pressure and temperature of the synthetic petroleum inclusions closely match the actual pressure and temperature applied in the experiment. By reference to the burial and geothermal history of the Tarim host rocks, it was inferred that Types I, II and III petroleum inclusions represent fluids associated with three distinct phases of petroleum emplacement in the Lower Ordovician strata of this area, occurring during late Silurian to early Devonian, Cretaceous to early Tertiary, and late Tertiary, respectively. Type IV petroleum inclusions occur only in some fine calcite veins from few samples, and are believed to be related to an anomalous thermal event in this area. On the basis of the trapping pressures and trapping temperatures of the petroleum inclusions, three main phases of the petroleum-filling of the Lower Ordovician reservoirs can be delineated. Phase I and phase III petroleum events were related to petroleum migration and accumulation from the Lunnan Low Uplift or nearby area. The petroleum of the phase II petroleum event appears to have originated from Middle and Upper Ordovician source rocks in the northern slope area of the Manjiaer Depression with a long distance migration. [Copyright &y& Elsevier]

• Feature extraction method can extract required data from the raw scanning data. • Derive the optimal position of leapfrog balls and improve calibration accuracy. • Use SVM to determine the parameters of edge-determination method. • Complex components can be measured and analyzed. • The proposed method can significantly reduce time consumption. In the manufacturing industry of aviation equipment (e.g., ballistic missile, rocket, unmanned aerial vehicle (UAV), and airplane), the traditional assembly quality inspection methods mainly rely on manual operation of single- or multi-stations laser trackers, but they are powerless to measure and evaluate complex components on the aviation equipment. This paper introduces a method for automatically detecting and evaluating assembly accuracy: first, the global accurate calibration is performed automatically by deriving the optimized positioning of leapfrog balls; after selecting the aviation equipment type to determine the measurement tasks, each side of the aviation equipment is equipped with a robot and an accompanying FARO scanning arms that can move together on the U-shaped guide rail to the measurement station where the measurement task is to be performed; at each measurement station, the robot drives the movement of the FARO scanning arm through a linkage mechanism to perform scanning; after the whole measurement processes are completed, data from multiple measurement stations is integrated into the same coordinate system for calculation and assembly quality analysis. The algorithm module consists of path planning function for scanning various parts, feature extraction function for various geometric elements, and assembly quality evaluation function. Compared with laser tracker method, the proposed method can effectively and accurately measure and analyze basic measurement tasks: the maximum differences of length, concentricity, and perpendicularity are all less than 0.3%; while the time consumption can be significantly reduced to less than 5% of that of the laser tracker method. Moreover, the proposed method can also achieve the automatic measurement and analysis of complex positioning components that cannot be achieved by laser trackers, e.g., center of positioning hole, position deviation of the bump, and azimuth angle between the positioning surfaces. [ABSTRACT FROM AUTHOR]

Abstract: The effects of geometric structures of coated particles on the dielectric properties of composites are derived. For a dilute suspension of coated ellipsoids with dielectric core and metallic shell embedded in a linear dielectric host, we find that the optical absorption peak of maximum wavelength shifts due to the core–shell structure, and has a significant red shift from that of pure metallic particles, especially for thin metallic coating. Meanwhile, the shape of coated ellipsoid can tune the absorption peak in a wide frequency range by properly choosing the depolarization factor. When the composite is made of linear materials, we obtain the condition of partial resonance for coated ellipsoids, which is relative to the particle shape. Under such a condition, the property of the inner core can be extended to the outer shell. When the inner core is a weakly nonlinear material, the nonlinearity of the composite can be greatly enhanced at the linear partial resonance. To achieve the condition of partial resonance, a metallic shell may be suitable to reach the case if the frequency is far away from the plasmon frequency. It indicates that the nonlinearity can also be enhanced in terms of the geometric structure of materials as well as the properties of themselves. [Copyright &y& Elsevier]

Colorectal cancer is one of the most common cancers in the world, poorly responding to available chemotherapeutic agents. To investigate whether natural molecules can inhibit colon cancer progression, we investigated a principle phytoestrogen found in soybean known as daidzein, and determined its effects on the human colon cancer cell line LoVo. LoVo cells were treated with 0.1, 1, 5, 10, 50 and 100 μM daidzein for 2, 3, 4 or 5 d. The results indicated that daidzein stimulated the growth of LoVo cells at 0.1 and 1 μM whereas at higher concentrations (10, 50 and 100 μM) cell growth was inhibited in a dose-dependent manner. Treatment of daidzein at 10, 50 and 100 μM resulted in cell cycle arrest at G0/G1 phase, DNA fragmentation and increases in caspase-3 activity. There were no changes in alkaline phosphatase activity (ALP), an indicator of cell differentiation, upon treatment with daidzein when compared to controls. These results indicate that daidzein has a biphasic effect on LoVo cell growth and its tumor suppressive effect is by means of cell cycle arrest and apoptosis but not through cell differentiation. [Copyright &y& Elsevier]

Concerns surrounding climate change and environmental challenge make the coal utilization network essential not only for understanding the pattern of energy provision and transfer, but also for illustrating the interaction between anthropogenic activities and ecological systems at global level. This paper fills the research gap by dint of multi-regional input output model to outline coal embodied routes from natural boundaries to economic activities, and to identify the central hubs in the global coal supply chain, based on the most recent available statistics for 2011. As the economic value and environmental influences of different kinds of coals could be remarkably diverse, the separation of coal categories in systematic analysis could provide fundamental information regarding the displacement and teleconnection of coal utilization in the world. The estimation shows that in weight 64.99% of coal direct supply is ultimately embodied in international trade, indicating the crucial roles of trade interlinks in global coal utilization. Apart from this, the findings pertinent to sectoral structure, regional supply chain and per capita characteristics of coal embodied utilization, could be valuable to identify the global energy routes driven by international trade as well as to facilitate energy and environmental policy. [ABSTRACT FROM AUTHOR]

The classic renin–angiotensin system (RAS) is a complex system in which angiotensin II (Ang II) has been identified as an important endogenous regulator that influences both smooth muscle contraction and cell growth. Although a local RAS is known to exist in the gastrointestinal tract, it is unclear whether Ang II is involved in the loss of gastric interstitial cells of Cajal (ICC) in diabetic mice. The present study was designed to investigate the effect of Ang II on ICC survival in streptozotocin (STZ)-induced diabetic mice. Western blot, immunofluorescence, isometric muscle recording, enzyme-linked immunosorbent assay (ELISA) and a cell counting kit-8 were used in this research. Our results demonstrate that the c-Kit and membrane-bound stem cell factor (mSCF) protein expression levels in gastric smooth muscle were decreased in STZ-induced diabetic mice. However, the angiotensin receptor type 1 (AT1R) expression levels in gastric smooth muscle and angiotensin-converting enzyme (ACE) expression levels in gastric mucosa were increased. The effect of Ang II on the tonic contraction of gastric smooth muscle was potentiated in diabetic mice, and the plasma Ang II level was enhanced. Ang II increased mSCF expression, cell proliferation, and Akt-Ser473 phosphorylation in cultured gastric smooth muscle cells (GSMCs). These effects were reduced by specific inhibitors ZD7155 (an AT1R antagonist) and LY294002 (a PI3-kinase inhibitor). Our results suggest that Ang II increases mSCF expression and cell proliferation in cultured GSMCs in a PI3K/Akt signaling-dependent manner. ACE and AT1R up-regulation in the stomach may help compensate for ICC loss in STZ-induced diabetic mice. [ABSTRACT FROM AUTHOR]

• We present a Six-Point positioning algorithms which can automatically update tool coordinate system. • We choose two kinds of measurement paths for testing the wall thickness values of the blades. • Our method can automatically determine suitable adjustment parameters for distorted wave shapes. • Our method demonstrates excellent precision, accuracy, and stable. It can greatly improve the measurement efficiency. Compared with inner solid structures, the inner hollow structures of turbine blades show excellent mechanical properties and better physical properties, e.g., excellent heat dissipation and diversion effects, and light weight. Its complex inner structures cannot be detected accurately by traditional testing methods. Among all non-destructive testing (NDT) methods, ultrasonic testing method has certain advantages in measurement accuracy and efficiency for measuring wall thickness values. The accuracy of measurement results is provided by four criteria: precision, accuracy, stability, and efficiency. However, ultrasonic testing method still faces new challenges that are barely explored, e.g., inner structures have unique characteristics of complex geometrical features, the measurement process need to meet high-precision positioning and quickly detecting requirements. In this paper, in order to improve the detection accuracy and efficiency, an industrial robot is used to substitute the existing detection methods: once a new blade is clamped by terminal mechanism, a new calibration method adopted the six-point positioning scheme was provided to solve the problem of rapid and accurate updating tool coordinate system. The support vector machine (SVM) system was used to output regression results of the adjustment parameters based on the geometric features of distorted wave shapes. Two kinds of measurement paths were used to measure the wall thickness values for accurate measurement. The experimental results show the superiority and effectiveness of our method in terms of measuring stability, accuracy and testing efficiency. [ABSTRACT FROM AUTHOR]

Abstract: To understand the phytoremediation capability of poplar 107 (Populus × euramericana cv. ‘Neva’) and poplar 118 (Populus nigra × Populus ussuriensis) stressed by cadmium (Cd), a hydroponic culture was performed. Cd accumulation and translocation were evaluated, activities of antioxidant enzymes and lipid peroxidation were assessed and ultrastructural alterations in root tip cells were investigated. The superoxide dismutase (SOD) activity in the leaves of the two cultivars exposed to 50μM and 100μM Cd was significantly higher (P <0.05) than that of the control and SOD activity in the roots was low. The levels of peroxisome (POD) and catalase (CAT) were significantly higher (P <0.05) than those of the control. The content of malondialdehyde (MDA) increased during the treatment. The morphological alterations in plasma membrane, dictyosomes and ER reflect the features of detoxification and tolerance under Cd stress. Reduction in number of ER, mitochondria and dictyosomes, swelling of rER and significant expansion of mitochondrial cristae were observed. The plasma membrane was damaged and cytoplasmic electron density increased, revealing a pool-like structure. Some electronic-dense granules occurred in the cytoplasm or cell wall. Plasmolysis occurred in some cells. The poplar cultivars used in the present study could be efficient phytoextraction plants as they have considerable ability to accumulate Cd (Cd concentration in shoot exceeding 0.01% (w/w)). The alterations of antioxidant enzymes and MDA content and ultrastructural changes in the poplar cultivars can serve as useful biomarkers in ecotoxicological tests with Cd. [Copyright &y& Elsevier]

Abstract: China is a member of the ITER program and is developing her own materials for its shielding and test blanket modules. The materials include vacuum-hot-pressing (VHP) Be, CuCrZr alloy, 316L(N) and China low activation ferritic/martensitic (CLF-1) steels. Joining technologies including Be/Cu hot isostatic pressing (HIP) and electron beam (EB) weldability of 316L(N) were investigated. Chinese VHP-Be showed good properties, with BeO content and ductility that satisfy the ITER requirements. Be/Cu mock-ups were fabricated for Be qualification tests at simulated ITER vertical displacement event (VDE) and heat flux cycling conditions. Fine microstructure and good mechanical strength of the CuCrZr alloy were achieved by a pre-forging treatment, while the weldability of 316L(N) by EB was demonstrated for welding depths varying from 5 to 80mm. Fine microstructure, high strength, and good ductility were achieved in CLF-1 steel by an optimized normalizing, tempering and aging procedure. [Copyright &y& Elsevier]

Abstract: Background: Anti-CD25 monoclonal antibodies (Mabs) have been evaluated for the treatment of steroid-refractory acute graft-versus-host disease (GVHD) in patients undergoing hematopoietic stem cell transplantation (HSCT) mainly with matched donors for years, but there is little attention concerning patients with unmanipulated human leukocyte antigen (HLA)-mismatched/haploidentical transplantations. We investigated the efficacy and safety of the chimeric Mab, basiliximab, to treat steroid-refractory acute GVHD after unmanipulated mismatched/haploidentical HSCT. Methods: Fifty-three patients who developed steroid-refractory acute GVHD between July 2005 and July 2009 were treated at our institute with basiliximab. No prisoners were used in this study. Results: Forty-six among 53 patients responded, including 37 complete remissions at a median response of 6 days from Mab initiation. There were 29 episodes of viral reactivations, 25 bacterial infections, and 11 probable fungal infections. Thirty-four out of 49 patients who could be evaluated developed chronic GVHD. Twenty-eight of 53 subjects (52.8%) were alive at a median follow-up of 16 months (range, 2–57) posttransplantation. The Kaplan–Meier probability of a 3-year event-free survival was 47.7%. The causes of death were infection alone (n = 15), progressive GVHD with infection (n = 3), relapse (n = 3), and other etiologies (n = 4). Conclusion: These data suggested that basiliximab was effective to treat steroid-refractory acute GVHD after unmanipulated HLA-mismatched/haploidentical stem cell transplantation. [Copyright &y& Elsevier]

Abstract: Based on the electron–hole recombination ratio (the number of electron–hole recombination in unit time and volume), we have examined several P complexes surrounded with vacancy (V) or H to explore the effect of carrier compensation on the electronic properties in P-doped diamond by first-principle calculations. Our calculated results show that the monovacancy complex P–V–H is not a valid recombination center in P-doped diamond, in which case electron cannot be recombined and thus donor cannot be compensated. However, the level in the band gap introduced by the divacancy complex P–2V–2H is a valid recombination center, which accelerates the electron–hole recombination at high ratio. For the trivacancy complex P–3V, three levels are introduced near the middle of the band gap, which may serve as more valid recombination centers than others. In this case, the electron–hole recombination ratio enhances successively, namely, the compensator density increases continuously too. In addition, the electronic properties of the P-related complexes in negative charge states are similar with those of neutral charge states. The study may explain well the experimental results and be useful for the further experiment research. [Copyright &y& Elsevier]