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Tm3+:GdAl3(BO3)4 crystals were grown successfully from K2Mo3O10-B2O3 solvent by using the top seeded solution growth method. The absorption spectra for both σ and π polarizations were presented. The Judd-Ofelt (J-O) intensity parameters were found to be Ω2=4.54×10-20 cm2, Ω4=2.25×10-20 cm2, and Ω6=3.39×10-20 cm2. The spectroscopic parameters of this crystal such as the oscillator strengths, radiative transition probabilities, radiative lifetime as well as the branching ratios were calculated. Unpolarized and polarized emission spectra were obtained under the excitations of 468 and 797 nm, respectively. This crystal may be preferable for GaAlAs laser pumping. [ABSTRACT FROM AUTHOR]

The dynamics of polarization switching have been investigated over extremely broad time (10-8< t< 10² s) and field ranges for (001) c, (110) c, and (111) c-oriented Pb (Zn 1/3 Nb 2/3) O 3-4.5%PbTiO 3 crystals. The results demonstrate the presence of broad relaxation time distributions that can extend over a decade (s) in orders of magnitude in time, and which sharpen significantly with increasing field. The polarization transients have been fit to stretched exponential functions, which are typical of disordered systems. [ABSTRACT FROM AUTHOR]

Provides information on a study performing structure-property relationship in the La-modified lead zirconate titanate (PLZT) solution as a function of quenched La impurity content and Zr/Ti ratio. Methodology and materials used to conduct the study; Structural studies on various PLZT compositional sequences; Information on the interfacially modulated structure; Findings of the study.

It remains controversial whether carbohydrate can be efficiently used by crustaceans. Six isonitrogenous and isolipid diets were formulated containing 50-350 g kg-1 corn starch and were fed to juvenile prawns (mean weight, 0.133 ± 0.003 g) for 56 days in five replicates. Prawns fed 50-150 g kg-1 corn starch attained significantly greater weight gain. Digestive enzyme activities were significantly affected by dietary corn starch level. Hepatopancreatic and muscle glycogen levels peaked in prawns fed 350 g kg-1 and 150 g kg-1 corn starch content, respectively. Prawns fed 350 g kg-1 corn starch had a significantly higher haemolymph glucose level than that in the other groups. Hepatopancreatic hexokinase ( HK) activity increased significantly as corn starch level was increased. Hepatopancreatic pyruvate kinase ( PK) activity of prawns fed the 150 g kg-1 and 250 g kg-1 corn starch was significantly higher than that of prawns fed 50 g kg-1 corn starch. Including carbohydrate in the diet promoted increased lipogenic activities (glucose-6-phosphate dehydrogenase and malic enzyme) in the hepatopancreas. Hepatopancreatic HK and PK mRNA expression levels had similar trends with their activities. The 350 g kg-1 corn starch level induced the highest glucose-6-phosphatase and pyruvate carboxylase mRNA expression levels. Overall, moderate metabolic adaptations for using dietary corn starch were detected in Macrobrachium nipponense; however, a high proportion (>150 g kg-1 ) of corn starch in the diet may reduce growth. [ABSTRACT FROM AUTHOR]

In the aviation industry, flexural distortion of thin-walled aeronautic parts after machining processes is inevitable, especially for high-strength aluminum alloy. To satisfy the accuracy requirement for subsequent assembly processes, the distorted parts have to be corrected. Bilateral rolling operation has been proved to be an effective method for correcting the flexural distortion. However, this method is generally based on trial and error, and the quality of distortion correcting cannot be guaranteed. To solve this problem, finite element method (FEM) was first adopted to investigate the distortion feature after bilateral rolling process for T-shaped structures. The relationship between processing parameters and maximum deflection was then studied. An equivalent bending moment method was proposed to represent the effects of bilateral rolling on micro-plastic deformation and residual stresses. Besides, a theoretical model was established for distortion prediction. Furthermore, based on simulation results, the calculation formula of the equivalent load was deduced. Finally, the theoretical model and the equivalent bending moment method were verified by rolling correction experiments, which were used to calculate the rolling correcting load (rolling depth). The results show that the average reduction rate of deflection is 73.5%. This paper provides an effective theoretical model for predicting the correction load in rolling correction process for thin-walled aeronautic parts. [ABSTRACT FROM AUTHOR]

Purpose -- The key purpose of this study was to investigate the effects of different ultrasonic irradiation times on the wettability and other properties of the resulting water-based coating. The subject water-based coating was prepared using water-soluble polyester and amino resins by ultrasonic oscillation. Design/methodology/approach -- The coating was prepared by polymerising polyester and amino resins in water using ultrasonic oscillation. The coating was baked for 40 seconds at 350°C to coalesce and solidify the film. The contact angle, thermal stability and mechanical properties of the film, as well as the molecular weight (MW) and structure of the polyester resin, were determined. Findings -- The contact angle of the coating was found to decrease with ultrasonic irradiation; the mechanical properties and thermal stability were not altered when the irradiation time was longer than 5 hours. The MW of the polyester initially decreased then increased and stabilized with ultrasonic irradiation. The structure of polyester molecule and aggregated state of the solidified coating were not changed by ultrasonic irradiation. Research limitations/implications -- In the study reported here, the effects of different ultrasonic irradiation times were investigated. Results of this research could benefit in-depth understanding of the influence of ultrasonic treatment on polyester resins and polyester coatings and could further promote the development of water-based coatings. Originality/value -- The contact angle of the water-based coating decreased by mechanical means. The effects of ultrasound on microstructure and properties of the coating and resin were discussed in detail. [ABSTRACT FROM AUTHOR]

Wang, F.; Wang, H.; Zong, Y.; Andersen, T.J.; Pei, Y.D.; Tian, L.Z.; Li, J.F., and Shang, Z.W., 2014. Sedimentary dynamics along the west coast of Bohai Bay, China, during the twentieth century. To investigate the most recent changes in sedimentation along the west coast of Bohai Bay, China, we collected twelve 1-2 m short cores of undisturbed sediment from tidal flats off the city of Tianjin, using an Eijkelkamp corer. Based on the excess or unsupported 210Pb and 137Cs activities measured from the sediment cores, the chronology of the sediment sequences was established, from which the sedimentary history of the tidal flats was reconstructed. Results inform spatial and temporal variations in sedimentation rate along the Tianjin coast, from which sedimentary dynamics can be deduced. Two important time boundaries are identified. As the Luanhe River had migrated northwards since 1915, sediment supply to the northern section of the coast had reduced. Around 1958, several rivers were dammed. Since 1985, the need for dredging the Tianjin Port has decreased. These actions have resulted in a decline of sediment supply from these rivers, including Haihe, to both the northern and southern sectors of the coast. Once the supply of sediment from rivers was reduced, tidal processes acted to modify sediment characteristics, and an upward-fining pattern is recorded in the majority of sediment cores in this study. This study highlights the usefulness of applying both 210Pb and 137Cs dating methods. These dating methods, together with detailed sedimentary analysis, can provide valuable sedimentary evidence of coastal change and natural and human causes of change. [ABSTRACT FROM AUTHOR]

Recent findings suggest that creep occurs during thermal cycling of ultrasonically bonded wires, the extent of which is influenced by the nature of the temperature cycle, particularly its peak temperature. In this work, this hypothesis is investigated through a study of the power-law creep behavior of bonded 375- μm aluminum wires that have been thermally cycled. Data from a study of two wire purity levels (99.999% and 99.99%) and two different cycling profiles (−55°C to 125°C and −60°C to 170°C) are presented. Room-temperature creep stress exponents are derived for the wire bonds from constant-load nanoindentation tests and compared with their respective microstructures. [ABSTRACT FROM AUTHOR]

In the present research, the microstructural alteration and microhardness at near-surface of AISI H13 steel by hard milling under different cutting parameters with coated cutting tools have been investigated. Very thin white layer forms or even no obvious microstructural alteration layer appears at the near-surface. It is reasonable that the formation of the very thin white layer is primarily due to mechanical effect (severe plastic deformation) rather than thermal effect (rapid heating and quenching). The ‘hook’ shape of the microhardness profile indicates that the highest microhardness appears on the very top surface; while the smallest microhardness occurs at the depth of 25 µm below the machined surface. Moreover, the microhardness profiles below the machined surfaces well correlate with the microstructural change of the machined near-surface. It is expected that the experimental results will provide a useful guide to control or minimize the white layer formation and, more significantly, to promote the application of hard milling technique in die and mold industry. [ABSTRACT FROM PUBLISHER]

The distribution of substituents in lead zirconate (PZ) modified by K+ (PKZ) has been studied by high-resolution Z-contrast imaging. Pronounced intensity variations were observed between various Pb columns, giving direct evidence that a number of columns had higher concentrations of (K+) substituents. High-resolution Z-contrast imaging was also performed in La+3-modified lead zirconate titanate (PLZT) for comparison. [ABSTRACT FROM AUTHOR]

Polarization reversal and domain dynamics have been investigated in 0.7Pb(Mg 1/3 Nb 2/3 )O 3 -0.3PbTiO 3 using a method of current transients. Investigations were performed as a function of applied electric field. The kinetics of the transients have been modelled by a stretched-exponential-type function. [ABSTRACT FROM AUTHOR]

Temperature dependent dielectric constant measurements have been performed on [ABSTRACT FROM AUTHOR]

Bismuth ferrite is a magneto-electric material, which simultaneously has polarization and spin orders. We have used electron spin resonance (ESR) as a local probe of the magnetic order in the magnetic field range of 0-25 Tesla, in the frequency domain of 115 to 360 GHz, and at a temperature of 4.2 K. [ABSTRACT FROM AUTHOR]

It has been found that laminate composites of longitudinally magnetized magnetostrictive and transversely poled piezoelectric layers (an L-T laminate composite) have a giant magnetoelectric (ME) effect. Relatively high ME coupling, that is significant exchange between magnetization and polarization, is demonstrated. [ABSTRACT FROM AUTHOR]

Compositional modifications of ferroelectric BaTiO 3 were systematically investigated for Nb +5 substituents ( x ). Relaxor ferroelectric behavior was induced for x ≥ 4 at%. [ABSTRACT FROM AUTHOR]

A novel reflectarray element using an interdigital gap loading structure is proposed. A wide reflection phase range of more than 1000° is obtained, which can support a sufficient phase range for a large scattering angle (up to 60°) reflectarray. Furthermore, this element has a feature of equal element size because the reflection phase is adjusted by controlling the finger length of the interdigital gap. Thus, abrupt geometry variations for consecutive cells in the traditional reflectarray can be avoided. A Ku-band reflectarray has been fabricated and measured results show good agreement with simulation. [ABSTRACT FROM AUTHOR]

A magnetoelectric laminate composite consisting of magnetostrictive Terfenol-D (Tb1–xDyxFe2–y) and piezoelectric Pb(Zr,Ti)O3 layers has an extremely high voltage gain effect of ≈300 at its resonant state, offering potential for high-voltage miniature transformer applications. [ABSTRACT FROM AUTHOR]

The dynamics of polarization switching have been investigated over extremely broad time (10[sup -8]

Describes the re-coarsening of the refined crystals in the undercooled Cu-30at.percent nickel alloy. Design of different solidification times by changing the weight of samples and the cooling condition; Use of an infrared pyrometer to supervise the temperature of samples; Rapid solidification of bulk undercooled melts under adiabatic condition; Changes of critical undercooling with solidification times; Microstructures of Cu-30at.percent nickel; Conventional solidification of single phase alloys.

The presence of small basic DNA-binding proteins, or histone-like proteins (HLPs), in dinoflagellate nuclei has been well documented. Genes for HLPs have been cloned from Crypthecodinium cohnii ( HCc 1 and 2) and Alexandrium fundyense ( HAf ) but their predicted protein sequences show no homology to histones from other eukaryotes or to bacterial HLPs. The precise role of these HLPs in dinoflagellate nuclei is uncertain; the HLP:DNA ratio is too low to facilitate packaging of the entire (very large) genome. In order to investigate the role of these proteins we have cloned a gene for a HLP from Gonyaulax polyedra ( HGp). Unlike the genes from C. cohnii, the G. polyedra gene contains no introns. It codes for a protein with a predicted molecular mass of 10,985 Da, and an isoelectric point of 10.5. We over-expressed this protein in Escherichia coli using a construct that expresses the full-length protein with an N-terminal histidine tag, and purified it by Nickel-affinity and cation-exchange chromatography. While the predicted molecular mass of the fusion protein is 12,973 Da, similar to sizes observed for acid-soluble G. polyedra nuclear proteins, the relative mobility on denaturing SDS-polyacrylamide gel electrophoresis is 20,000 Da. We attribute the slower mobility in denaturing page to the basicity of the protein and predict that the relatively faster mobility exhibited by native HGp is due in part to post-translational modification of basic residues. Such modifications have been observed in histones and play an important role in the regulation of transcription in eukaryotes, a function that HLPs may assume in dinoflagellates. This possibility is being investigated. [ABSTRACT FROM AUTHOR]