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Lattice dynamic properties of bismuth ferrite with 6% bismuth vacancies have been investigated in present work for the first time. Hellmann–Feynman forces of each atom were calculated by direct method in the framework of density functional theory, and strong electron correlations of Fe ion were taken into account by applying the Hubbard potential U and the exchange interaction J . Based on the analysis of partial phonon density of states, effective force constants of Fe–O bond are influenced by the altered nearest coordination of oxygen due to bismuth vacancy. This behavior is connected with the soft phonon modes observed in the low energy range of phonon dispersion curve of nonstoichiometric Bi 0.94 FeO 3 . Low-temperature heat capacities are showing essential difference between nonstoichiometric and stoichiometric system that optic phonon modes begin contribute to the heat capacity from 3 K in Bi 0.94 FeO 3 , earlier than 7 K in BiFeO 3 . [ABSTRACT FROM AUTHOR]

Examines the Y-chromosome STR haplotypes in a Han ethnic group of Chinese population. Collection of blood samples; Allelic variation at the three Y-STR loci; Gene diversities.

As-cast Mg–5.3Zn–0.6Ca (weight percent) alloy was indirectly extruded at 300 °C with different deformation rates (ram speeds of 0.1, 0.3, 0.5 mms − 1 ), and the microstructure, texture and mechanical properties of the as-extruded alloys were investigated in the current study. With the increase of deformation rates, the average size and volume fraction of dynamic recrystallized grains were remarkably increased. The basal fiber texture became weak in the as-extruded alloy with higher volume fraction of recrystallized grains, because most of the basal planes in these grains were tilted to extrusion direction about 30–40°. The higher deformation rate decreased the tensile yield stress due to the grain coarsening and basal texture weakening, while the elongation was improved, which was resulted from the enhanced work hardening rate. [ABSTRACT FROM AUTHOR]

Inconel 718 was subjected to various heat treatments, i.e., solution heat treatment, standard ageing treatment and standard ageing plus 700 °C thermal exposure. The mechanical properties of the alloys were determined using tensile tests and Charpy pendulum impact tests at 650 °C and room temperature, respectively. The highest yield strength of 988 MPa was attained in the standard aged specimen, whereas a maximum impact toughness of 217 J cm −2 was attained in the solution-treated specimen. After thermal exposure, the mechanical properties of the specimens degrade. Both the yield strength and impact toughness decreased monotonically with increasing thermal exposure time. Subjected to a 10000-h long-term thermal exposure, the yield strength dramatically decreased to 475 MPa (almost 50% of the maximum strength), and the impact toughness reduced to only 18 J cm −2 . The microstructures of the specimens were characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Coarsening of γ′ and γ″ and the transformation of γ″ to δ-Ni 3 Nb was observed after thermal exposure. However, a complete transformation from metastable γ″ to δ-Ni 3 Nb was never accomplished, even after the 10000-h long-term thermal exposure. Based on the obtained experimental results, the effects of the microstructural evolution on the mechanical properties are discussed. [ABSTRACT FROM AUTHOR]

The yield strength of the extruded Mg−9.9Y−3.7Zn (wt%) alloy at room temperature is remarkably increased from 240 MPa to 364 MPa using low-stain rolling. This significant improvement is ascribed to the combination of intensive basal texture, fine long-period stacking ordered phase particles and a high density of dislocations. The elongation of the rolled alloy increases as the strain of rolling increases, which is attributed to the homogenous distribution of fine long-period stacking ordered phases. [ABSTRACT FROM AUTHOR]

Abstract: The characteristics of continuous-wave and actively Q-switched laser operations at 1359.5nm of (Nd0.005Lu0.4975Y0.4975)2SiO5 (Nd:LYSO) crystal were investigated. The maximum continuous-wave output power was 856mW at an incident pump power of 8.32W, corresponding to an optical conversion efficiency of 10.3% and a slope efficiency of 19.2%. By using an acousto-optical (AO) modulator, the Q-switched laser operation was realized. The maximum average output power, shortest pulse width, largest pulse energy and highest peak power of the Q-Switched laser were 534mW, 45.1ns, 92.4µJ and 2.05kW, respectively. [Copyright &y& Elsevier]

Abstract: The microstructure and texture evolution of Mg98.5Y1Zn0.5 and Mg92.5Y5Zn2.5 (atomic percent) alloys during hot extrusion were systematically investigated. The coarse LPSO phases with higher volume fraction (~57%) suppressed the twinning generation in the initial stage of extrusion, and accelerated the dynamic recrystallization through the particle deformation zones. Therefore, the volume fraction of DRXed grains in as-extruded Mg92.5Y5Zn2.5 alloy was much higher than that of Mg98.5Y1Zn0.5 alloy. The intensive recrystallization process resulted in the conventional basal texture weakening, although the texture evolution was mainly dominated by flow behavior. The dynamic recrystallization behavior in Mg92.5Y5Zn2.5 alloy restricted the formation of deformation texture, and thus the more random texture was observed during the whole extrusion process. [Copyright &y& Elsevier]

Abstract: The compressive deformation behavior at elevated temperature of the as-extruded and as-ECAPed Mg–5.3Zn–0.6Ca (wt%) alloys was investigated in the current study. The flow stress in the as-ECAPed alloy was lower than that of the as-extruded alloy when the compressive temperature was above 200°C, due to the grain boundary softening effect. The strain rate sensitivity (SRS) was remarkably enhanced with the decrease of grain size or the increase of test temperature, and the corresponding m-value was calculated as 0.06–0.13, which indicated that the deformation was mainly dominated by the climb-controlled dislocation creep. Furthermore, the grain boundary sliding (GBS) mechanism might also be activated, which contributed to the higher SRS in the as-ECAPed alloy. The true deformation activation energy ( ) modified by threshold stress was calculated as 92–98 and 70–76kJ/mol in the as-extruded and as-ECAPed alloy, respectively, which was close to the activation energy for grain boundary diffusion, and the lower -value in the as-ECAPed alloy might be derived from the non-equilibrium grain boundaries. [Copyright &y& Elsevier]

Highlights: [•] An optimized design of HTS binary current leads is proposed. [•] Temperature distributions of two different current leads are calculated. [•] Experiments are done to certify the calculated temperature distributions. [•] The experiments proved that the copper wires increase security margins. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a rare earth (RE) free Mg69Zn27Ca4 bulk metallic glass (BMG) of diameter 1.5mm was successfully fabricated by the injection casting method using recycled materials in atmospheric air. Without using high vacuum conditions, high purity starting materials and expensive rare earth materials, the findings of the work are of significance in reducing the cost and improving the manufacturability of BMGs. The results of the uniaxial compression tests further showed that there were no obvious differences between BMGs prepared under high vacuum or in atmospheric environment. The electrochemical polarization measurements in simulated physiological media revealed that the atmospheric Mg69Zn27Ca4 BMG manifested much lower passive current densities, higher pitting potential and a wider passive region than those of ZK60 and pure Mg alloys. The findings not only present Mg69Zn27Ca4 BMG as low cost material for potential biomedical applications, but also provide new insights into understanding of the effects of oxygen on glass formation. [Copyright &y& Elsevier]

Positron annihilation lifetime (PAL) spectroscopy is widely used in the characterization of material microstructures. It has a very high sensitivity to the material defects. This paper describes how we developed a digital PAL spectrometer with two barium fluoride (Ba F 2) detectors and reading the data with a fast digital oscilloscope. We achieved better time performance for the digital PAL spectrometer using a multi-parameter discrimination method and various pulse smoothing algorithms. With two Ba F 2 detectors in the coincidence mode, we achieved a time resolution of 160 ps for 0.511 MeV annihilation gamma rays. The multi-parameter discrimination method implemented can remove incorrect events more effectively than the conventional energy discrimination method. With this enhancement in event discrimination, the digital PAL spectrometer's time performance has improved, which results in more accurate PAL characterization. In a lifetime measurement, the PAL spectrometer's time resolution is about 130 ps, which is much better than most PAL spectrometers. With the multi-parameter discrimination method, the resolution component from the incorrect events decreases drastically, and the leading edge distortion of the PAL spectrum is significantly improved. [ABSTRACT FROM AUTHOR]

• The misfit dislocation patterns of hcp/bcc semicoherent bimetal interfaces with B and PS ORs were characterized. • The deformation mechanism of dislocation nucleation and phase transformation is revealed, where the former is closely related to dynamic evolution of misfit dislocation patterns and the latter is correlated to the specific loading mode and interface structure. • The phase transformation path for the required atomic rearrangements were revealed. • Competition relationship between non-basal dislocation nucleation and phase transformation were revealed via twisted interface models. The nucleation of lattice dislocations and interface sliding at bimetal interfaces are two fundamental mechanisms of plasticity that are responsible for the mechanical responses of nanostructured materials; however, the interface-facilitated phase transformation is rarely considered owing to its relatively high energy barrier for activation. Taking the bimetal hcp/bcc interfaces with Pitch-Schrader and Burgers orientation relationships (ORs) as an illustration, we show that both non-basal dislocation nucleation and hcp-to-bcc phase transformation can be activated at the interface under external loading when the basal slip systems are effectively suppressed. The non-basal dislocation nucleation is shown to be closely related to the dynamic evolution of misfit dislocation patterns at the semicoherent interface, in which the 1/6 [ 02 2 ¯ 3 ¯ ] pyramidal dislocation is not strictly parallel to the (01 1 ¯ 1) stacking fault plane owing to the corrugated feature. In contrast to non-basal dislocation nucleation, phase transformation requires specific crystallographic ORs of the constituent metals under certain loading conditions, which corresponds to the process of alternate shuffle and shear deformation that involves atomistic migration. To further reveal the competition between non-basal dislocation nucleation and phase transformation, a series of twisted interface models were constructed to systematically investigate the optimal condition of the interface geometry for phase transformation. The phase transformation occurred only when the dislocation nucleation was further hindered at some specific twist angles, suggesting a strong dependence of phase transformation on the interface structure. These findings provide a foundation to the atomistic mechanism of various interface-mediated deformation and a solution to tune interface-facilitated plasticity via interface engineering. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, a novel Fe43Co4.5Cr16.5Mo16.5C14B4Y1.5 (at.%) bulk metallic glass rod with 10mm in diameter has been developed by Cu-mold suction casting using commercial grade raw materials. The thermal stability and corrosion behaviors of the centimeter-sized Fe-based alloys have been studied by differential scanning calorimeter and electrochemical measurements, respectively. The as-cast Fe-based alloy exhibits a high glass transition temperature of 820K and a large super-cooled liquid region of 60K, demonstrating an excellent thermal stability. Moreover, the Fe-based alloy developed appears to have corrosion resistance comparable to (or better than) that of 316L stainless steel, based on the measurements of breakdown potential and corrosion weight loss in simulated acid rain and seawater solution. The affluent of chromium and molybdenum elements included is conceived to be highly responsible for the high corrosion resistance in the current Fe-based bulk metallic glass, which may be good candidates to be used as low-cost, high-strength, and corrosion-resistant amorphous alloy. [Copyright &y& Elsevier]

Abstract: Indirect extrusion of as-cast Mg–5.25 Zn–0.6 Ca (wt%) alloy was performed at 300°C with different extrusion ratios (ER, 20:1 and 10:1), and the microstructure, texture and tensile properties of the as-extruded alloys were investigated in the current study. With the increase of ER, the volume fraction of DRXed grains was remarkably increased, but the average DRXed grains size was almost unchanged. The basal texture weakening phenomenon occurred in the as-extruded alloy with higher ER, which resulted from the higher volume fraction of the DRXed grain. Intensive basal fiber texture was observed in the unDRXed grains, but the basal planes of the DRXed grains were inclined to ED from 0° to 35°. The ER had only little effect on the tensile properties of the as-extruded alloys; due to the similar strengthening effect from the unDRXed and DRXed grains, a competitive mechanism exists between the fine grain strengthening and texture weakening effect. [Copyright &y& Elsevier]

1. A 2 × 2 factorial design was used to investigate the differences in carcase, muscle and meat characteristics between fast and slow growing genotypes fed on low nutrient (LND) or high nutrient diets (HND) at their respective slaughter ages. 2. The birds were randomly assigned to treatments with 5 replicates of 145 birds for Wens Yellow-Feathered Chicken (WYFC, 5·75 birds/m2) or 115 birds for White Recessive Rock Chicken (WRRC, 7·25 birds/m2), according to the commercial recommendations for the two breeds and were fed on HND or LND. Birds were slaughtered at 63 d and 105 d of age. 3. The results showed WRRC had higher carcase yield and meat yield than that of WYFC, lower fat content, higher moisture content and lower cooking loss. The meat from WRRC was less tender and contained lower levels of polyunsaturated fatty acids (PUFA). 4. Birds fed on HND had higher breast meat yield, myofiber area and protein content in the breast muscle and lower fat content than birds fed on LND. The thigh muscle of birds fed on HND had higher levels of PUFA. Age had a positive effect on carcase parameters, but a negative effect on pH, meat tenderness and cooking loss, and the two genotypes exhibited different responses to the influence of nutrient density and age. 5. Genotype and age had the largest effect on carcase performance and meat quality. LND benefited meat quality and WRRC had larger responses in meat yield and shear force when fed on HND. [ABSTRACT FROM PUBLISHER]

Abstract: The mechanical properties at room temperature and the corrosion behavior in simulated body fluid (PBS) at 37°C of a Ni-free Zr62.3Cu22.5Fe4.9Al6.8Ag3.5 bulk metallic glass (BMG) were investigated. This BMG exhibits a good room temperature plasticity of 8%, a yield strain of 1.9% and a high fracture strength of about 1800MPa. Interestingly, the novel Zr-rich BMG possesses a specific strength (σ/ρ) of about 280MPacm3/g higher than that of conventional biomedical Ti6Al4V alloy and 316L stainless steel. In addition, this alloy also has a high corrosion resistance with a low corrosion penetration rate in simulated body fluids (PBS). The present Ni-free Zr-rich BMG with a critical diameter above 1cm, together with the high specific strength, large plasticity and good corrosion resistance in PBS, has excellent potential in biomedical applications. [Copyright &y& Elsevier]

Abstract: A Ni–9.5wt.% Y2O3 composite film has been developed by codeposition of Ni and Y2O3 microparticles with an average particle size of 2.5m onto pure Ni surfaces from a nickel sulfate. The Y2O3 microparticles were dispersed in the electrodeposited nanocrystalline Ni grains. The isothermal oxidation at 800°C for 30h and 1050°C for 20h in air showed that the as-deposited Ni–Y2O3 composite film has a superior oxidation resistance compared to the electrodeposited pure Ni film because the codeposited Y2O3 particles block the outward diffusion of nickel and change the oxidation growth mechanism of Ni. [Copyright &y& Elsevier]

Abstract: Single crystals of potassium tantalate niobate, KTa1−x Nb x O3 (KTN x , x =0.45, 0.50, and 0.55), were synthesized by the top-seeded solution growth method. The Raman scattering technique is used to investigate the sequence of phase transitions undergone by KTN x crystals. We discuss what features in the phonon spectrum are associated to each phase transition. [Copyright &y& Elsevier]

Abstract: SrO(SrTiO3) n (n =1, 2,…,∞) powders were prepared by a modified sol–gel self-propagating combustion method and characterized by ultraviolet–visible (UV–vis) absorption spectroscopy and infrared spectra. UV–vis spectra indicate that the absorption edge of SrO(SrTiO3) n (n =1, 2) shift to the violet with the decrease of n value, and the band gap values obtained from the UV–vis spectroscopy measurements are 3.41 and 3.26eV, respectively. The infrared spectra show that the width of absorption band of TiO6 octahedron stretching vibration decreases with the increasing of n value. The optical absorption of the compounds SrO(SrTiO3) n (n =1, 2,…,∞) were investigated by theoretical caculation using density functional theory (DFT). The interband transitions were assigned according to the partial density of states (PDOS). The calculated results are close to the experimental results. [Copyright &y& Elsevier]

Context: Whether natural product drug discovery programs should rely on wild plants collected 'randomly' from the natural environment, or whether they should also include plants collected on the basis of use in traditional medicine remains an open question. Objective: This study analyzes whether plants with ethnomedical uses from Vietnam and Laos have a higher hit rate in bioassay testing than plants collected from a national park in Vietnam with the goal of maximizing taxonomic diversity ('random' collection). Materials and Methods: All plants were extracted and subjected to bioassay in the same laboratories. Results of assays of plant collections and plant parts (samples) were scored as active or inactive based on whether any extracts had a positive result in a bioassay. Contingency tables were analyzed using χ2 statistics. Results: Random collections had a higher hit rate than ethnomedical collections, but for samples, ethnomedical plants were more likely to be active. Ethnomedical collections and samples had higher hit rates for tuberculosis, while samples, but not collections, had a higher hit rate for malaria. Little evidence was found to support an advantage for ethnomedical plants in HIV, chemoprevention and cancer bioassays. Plants whose ethnomedical uses directly correlated to a bioassay did not have a significantly higher hit rate than random plants. Discussion: Plants with ethnomedical uses generally had a higher rate of activity in some drug discovery bioassays, but the assays did not directly confirm specific uses. Conclusions: Ethnomedical uses may contribute to a higher rate of activity in drug discovery screening. [ABSTRACT FROM AUTHOR]

Abstract: The relation between the linear electro-optic effect and conoscopic interference has been investigated in a biased electro-optic crystal strontium calcium barium niobate (CSBN). Based on the change of interference patterns with applied field, an interferometric method for probing electro-optic coefficients of electro-optic crystals has been proposed. In our case, the linear electro-optic coefficients of CSBN:50 was first probed at γ 33=(141.0±0.5)×10−12 m/V and γ 13=(85.0±0.5)×10−12 m/V. [Copyright &y& Elsevier]

Abstract: We present a photochemical method for the laser directed deposition of silver thin films, through the illumination of a low power laser in a solution containing citrate and silver ions. With this method silver can be laser-directed to be deposited on a number of surfaces, such as metals, semiconductors, polymers and composites. In this study, we investigate the effects of applied light dosage (time variation) and chemical concentration of a precursor on the thin film deposits to support a proposed mechanism on the nucleation and growth of such Ag films and to outline the different conditions under which surface nucleation will be favoured. With this method, Ag can be selectively deposited by low power laser and has the potential to form maskless direct-write metallic periodic patterns via optical interference. [Copyright &y& Elsevier]

Abstract: For further investigation on the defect structure of lithium niobate (LiNbO3—hereafter LN) crystals using the neutron scattering technique, a congruent lithium isotope niobate (C7LN) crystal was grown by the Czochralski method from a 48.4% 7Li melt. The X-ray powder diffraction (XRPD) results show that the as-grown crystal is a single-phased (R3c) LN. We observed 4A1(TO)+7E(TO) Raman modes. The crystal composition (Li mol%) determined from UV absorption edge and Raman measurements is 47.47% and 47.34%, respectively. The specific heat (C p ), thermal diffusion coefficients (λ a, λ c), thermal conductivities (κ a, κ c) and the average thermal expansion coefficients (α a, α c) were determined. The effect of Li vacancy content is analyzed by comparing the results with those obtained for stoichiometric lithium isotope niobate (S7LN) and congruent natural lithium niobate (CLN) crystals. The values of all thermal parameters of C7LN are smaller than those of S7LN and CLN, which may be related to either the difference of vacancy content or isotope substitution. [Copyright &y& Elsevier]

Abstract: The adsorption of fluorescein on the Ag(110) surface has been investigated by the first-principles pseudopotential method. Various adsorption geometries have been calculated and the energetically most favorable structure of fluorescein/Ag(110) was identified. The fluorescein molecule, in most favorable structure, is on hollow site, and the adsorption energy is 2.34eV. Here the adsorption sites refer to the positions at the first layer of the substrate where the middle carbon atom of the fluorescein molecule is located. The bonding strength of the fluorescein molecule to the Ag substrate is site selective, being determined by electron transfer to the oxygen atoms of the molecule and local electrostatic attraction between the oxygen atoms and the silver atoms. [Copyright &y& Elsevier]

Abstract: SrO(SrTiO3) n compounds were prepared by a modified sol–gel self-propagating combustion, which is a low-temperature combustion synthesis procedure using microwave-assisted sol-gel as precursors. The thermal treating conditions were determined by DTA/TG analysis of the powders. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used for the sample characterization. The results confirm that the high temperature and long reaction time which occur in classical solid-state reaction method are avoided. The band structure, total density of states (DOS), and partial density of states (PDOS) of SrO(SrTiO3) n were calculated in order to study the electronic structures of SrO(SrTiO3) n . [Copyright &y& Elsevier]

[Display omitted] • Li can significantly decrease the degradation rate for Mg-based and Zn-based alloys. • Both tensile and compressive strain would promote the anode dissolution rate of both Mg-based and Zn-based alloys. • Tensile and compressive strain can increase the strain energy and decrease the energy barrier of reaction. • Electron polarization between solute atoms and solvent atoms are the main causes of the change of surface properties. Using density functional theory and an improved Butler-Volmer model, we comparatively investigate the underlining mechanisms of solute alloying and mechanical straining on the electrochemical polarization and degradation behaviors of both Mg-based and Zn-based alloys. Our results suggest that some elements such as Li can potentially decrease the degradation rates for both alloys, while others like Fe, Ni, Cu, and Al, will play an opposite effect. By introducing the scaled strain energy to study the strain effect on the degradation kinetics of both alloys, we further reveal that both tensile and compressive strain would promote the degradation rate by decreasing the activation energy barrier. [ABSTRACT FROM AUTHOR]

Abstract: This investigation witnesses the fact that the direction of the light-induced self-diffraction spot changes with different Ca2+-doped CSBN ((Ca0.28Ba0.72) x (Sr0.60Ba0.40)1−x Nb2O6) crystals, indicating that the formed noise-grating wave vector direction changes with different ion-doped. Based on the wave optics theory and light-induced self-diffraction under the incident of plane monochromatic light wave in CSBN crystals, the theoretical model of noise-grating is analyzed, constructed and validated in this work. [Copyright &y& Elsevier]

Studies the allele frequencies of two Y-short tandem repeat loci in a population in Chongqing, China. Extraction of DNA; Amplification of DNA; Analysis of the amplified products; Gene and haplotype diversities of the alleles.

Abstract: A passively Q-switched all solid-state Nd:LuVO4 1.06μm laser was demonstrated by using Cr4+:YAG as saturable absorber. The characteristics of average output power, pulse width, repetition rate, pulse energy, and peak power were studied with different output couplings and initial transmission of saturable absorbers. When output coupling with the transmission of 20% was used, the shortest pulse width of 16ns at the repetition rate of 12.5kHz was obtained, which results in the pulse energy of 71μJ and peak power of 4.43kW with the initial transmission of 70% of Cr4+:YAG crystal. [Copyright &y& Elsevier]

Abstract: In the present work, the edge-to-edge matching model has been introduced to predict the orientation relationships (OR) between the MgZn2 phase which has hexagonal close packed (HCP) structure and the HCP α-Mg matrix. Based on the crystal structures and lattice parameters only, the model has predicted the two most preferred ORs and they are: (1) , (2) . Four experimental ORs have been reported in the α-Mg/MgZn2 system, and the most frequently reported one is ideally the OR (2). The other three experimental ORs are near versions of the OR (2). The habit plane of the OR (2) has been predicted and it agrees well with the experimental results. [Copyright &y& Elsevier]

Abstract: The thin fluorescein films grown on Ag (110) have been studied by the ultraviolet photoemission spectroscopy (UPS). Four emission features are located at 2.7, 3.8, 7.4 and 9.8eV below the Fermi level, respectively. The angle-resolved ultraviolet photoemission spectroscopy (ARUPS) measurements show that the Triring plane of fluorescein is nearly parallel to the substrate and the axis of Ce to the azimuth. [Copyright &y& Elsevier]

Abstract: Large size strontium tungstate (SrWO4) single crystal was grown by Czochralski method. Raman scattering and infrared absorbance spectra measurements show that the characteristic lattice vibrational modes of SrWO4 arise mainly from the internal vibrations of the WO4 tetrahedra and partly by the external SrO8 polyhedra modes. Thermal properties including thermal expansion, specific heat, thermal diffusion and conductivities of the crystal were investigated to evaluate the thermal properties of SrWO4. The anisotropy of thermal properties was explained by crystal structure and its correlation with the lattice vibration spectra. [Copyright &y& Elsevier]

Abstract: Ethnobotany/ethnopharmacology has contributed to the discovery of many important plant-derived drugs. Field explorations to seek and document indigenous/traditional medical knowledge (IMK/TMK), and/or the biodiversity with which the IMK/TMK is attached, and its conversion into a commercialized product is known as bioprospecting or biodiversity prospecting. When performed in a large-scale operation, the effort is referred to as mass bioprospecting. Experiences from the mass bioprospecting efforts undertaken by the United States National Cancer Institute, the National Cooperative Drug Discovery Groups (NCDDG) and the International Cooperative Biodiversity Groups (ICBG) programs demonstrate that mass bioprospecting is a complex process, involving expertise from diverse areas of human endeavors, but central to it is the Memorandum of Agreement (MOA) that recognizes issues on genetic access, prior informed consent, intellectual property and the sharing of benefits that may arise as a result of the effort. Future mass bioprospecting endeavors must take heed of the lessons learned from past and present experiences in the planning for a successful mass bioprospecting venture. [Copyright &y& Elsevier]

Abstract: In this paper, we propose, analyze and demonstrate a high-purity float-zone (FZ) silicon phototransistor operating at the punch through state with high linearity and sensitivity. Those phototransistors were fabricated on high-purity FZ silicon substrates; the dependence of the sensitivity on incident optical power and bias voltages has been investigated to light with a wavelength of 0.83μm from a laser diode. In accordance with theoretical prediction, it shows that the linearity reaches the highest when the base of the phototransistor is completely depleted (punch through), and the fitting goodness of output R 2 is 0.9954 over a 40dB range from 0.15 to 1500nW. The sensitivity of the phototransistor can be as large as 40–70A/W at the punch through state, which is equivalent to an internal current conversion gain of about 75–130. The stability of 1% in the sensitivity for the punch through phototransistor with an internal current conversion gain of 130 can be obtained if the bias voltage and operating temperature can be stable to about 2.5% (1 in 40V) and the temperature to ±2°C. [Copyright &y& Elsevier]

Abstract: New data relating to flux growth, composition, homogeneity and physical characteristics of (R,Y)Al3(BO3)4 (R=Tm or Yb) crystals are discussed. Single crystals have been obtained using K2Mo3O10-based fluxes by spontaneous nucleation as well as by the top-seeded solution growth at cooling rates of 4.8–12°C/day and 0.2–5°C/day, respectively, in the temperature range from 1120 to 900°C. It is found that the average Tm and Yb segregation coefficients are close to unity, and vary from 0.80 to 1.02, as a consequence of minor difference in the sizes between Y3+ and R3+ cations. Two morphological types of (Tm,Y)Al3(BO3)4 crystals have been revealed. The average thermal expansion coefficients of Yb:YAB along a- and c-axis are measured as 2×10−6/K and 9.7×10−6/K, respectively, in the temperature range of 298–573K. The specific heat of the Yb:YAB crystal at room temperature is found to be 0.76J/gK, implying that this material can exhibit significant resistance to laser damage. Over 1.1W of green emission has been obtained from a diode pumped 3×3×3mm3 Yb:YAB crystal. The conversion efficiency of diode to green is 10%. High beam quality of green and IR emission can be easily attained due to the good crystal quality and lack of thermal effects. [Copyright &y& Elsevier]

In this study, we analyzed allelic sequences of 10 novel Y-specific STR loci, DYS454, DYS510, DYS513, DYS520, DYS542, DYS544, DYS552, DYS561, DYS587 and DYS593, surveyed the distribution of haplotypes in a Chinese Han population. Extracted DNA was amplified with PCR, followed by a horizontal non-denaturing polyacrylamide gel electrophoresis with discontinuous buffer system. Purified alleles were sequenced on DNA sequencer (ABI Model 377) to verify the number of motif repeats. The number of alleles observed at each locus ranged from 3 to 8, yielding 102 haplotypes in 103 unrelated males samples. The allele diversity values for each locus ranged from 0.2099 (DYS544) to 0.7523 (DYS552). The haplotype diversity using all these loci was 0.9998. Our study revealed that they were valuable Y-specific markers for forensic applications. [Copyright &y& Elsevier]

Using the d.c. reactive magnetron sputtering method we have successfully deposited completely (002)-oriented ternary Zn1-xCdxO (0≤x≤0.6) alloy crystal films without Cd segregation on Si(111) substrates. X-Ray photoelectron spectroscopy measurements show that Cd/Zn ratios in the films are nearly consistent with those in the targets. The Zn and Cd exist only in oxidized states, no evidence of metallic Zn or Cd was observed. The O/(Cd+Zn) atomic ratios of the films are in the range of 0.89–0.98. Transmission electron microscopy measurements show that for the (002)-oriented films the grains are columnar structures with the c-axis perpendicular to the Si substrate. By post-annealing treatments in O2 ambient, the crystal quality of the Zn1-xCdxO films can be improved. For the sample of x=0.2, the optimal annealing temperature is 500 °C. [Copyright &y& Elsevier]

Oval cells, putative hepatic stem cells, could potentially provide a novel solution to the severe shortage of donor livers, because of their ability to proliferate and differentiate into functional hepatocytes. We have previously demonstrated that oval cells can be induced to differentiate into cells with morphologic, phenotypic, and functional characteristics of mature hepatocytes. In this study, we have established a new model combining ethionine treatment with partial hepatectomy to activate oval cells, then developed a procedure utilizing selective enzymatic digestion and density gradient centrifugation to isolate and purify such cells from heterogeneous liver cell population. We identified oval cells by their morphological characteristics and phenotypic properties, thereby providing definitive evidence of the presence of hepatic stem-like cells in adult rat livers. Viewed by transmission electron microscopy, they were small cells with ovoid nuclei, a high nucleus/cytoplasm ratio and few organelles, including mitochondria and endoplasmic reticulum. Flow cytometric assay showed that these cells highly expressed OV-6, cytokeratin-19 (CK-19) and albumin. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis displayed that the freshly isolated cells co-expressed albumin, cytokeratin-7 (CK-7) and CK-19 mRNA, indicating that they were essentially bipotential hepatic stem-like cells. Furthermore, we set up a culture system containing growth factors and a fibroblast feeder layer, to provide nourishment to these cells. Thus, we were able to culture them in vitro for more than 3 months, with the number of cells doubling 100 times. Gene expressions of albumin, CK-7 and CK-19 in the cells derived from the expanding colonies at day 95 were confirmed by RT-PCR analysis. These data suggested that the hepatic oval cells derived from adult rat livers possess a high potential to proliferate in vitro with a large increase in number, while maintaining the bipotential nature of hepatic stem cells. [ABSTRACT FROM AUTHOR]

The protonated imidazole diphosphopentamolybdenum polyoxometalate (C 4 H 7 N 2 ) 4 [HP 2 Mo 5 O 23 ]·H 3 O· 4.5H 2 O has been synthesized and its structure has been determined by single-crystal X-ray diffraction. This compound crystallizes in the triclinic crystal system, space group P (-1), a = 10.171(2), b = 11.839(2), c = 20.170(4) Å, α = 75.69(3), β = 84.56(3), γ = 64.90(3)°, V = 2130.8(7) Å 3 , Z = 2 and R = 0.0329. The compound is composed of [HP 2 Mo 5 O 23 ] 5- clusters and and H 3 O + cations as well as water of crystallization, and forms a supramolecular network structure through hydrogen bonds. The monoprotonated polyanions are held together by two strong hydrogen bonds [ d O…O = 2.582(7) and 2.581(8) Å]. Density functional theory (DFT) calculation has been carried out to investigate the electronic properties of the [H n P 2 Mo 5 O 23 ] (6- n )- ( n = 0, 1, 2) polyanions. Mulliken charges for all atoms have been analyzed. The results show that the negative charges delocalize over all types of oxygen atoms, and molybdenum and phosphorus atoms accept electrons from the oxygen atoms. The protonation affects the charge distribution, redox properties and relative stability of the polyanion; the non-protonated polyanion [P 2 Mo 5 O 23 ] 6- can be more easily reduced. [ABSTRACT FROM AUTHOR]

We report on the preparation of luminescent silica mesoporous molecular sieves (MCM-48) activated by the europium complex Eu(DBM)3 · 2H2O (where DBM=dibenzoylmethane), using a simple wet impregnation method. Different concentrations of Eu(DBM)3 · 2H2O were introduced into the MCM-48 cubic structure, and the resulting samples were washed with ethanol for different times. UV–Vis absorption measurements and thermogravimetric analysis were used to estimate the amount of Eu complex that has been incorporated within the pores of the MCM-48 host. The various samples were characterized by X-ray powder diffraction (XRD), infrared spectroscopy, diffuse reflectance (DR) and fluorescence measurements. The results reveal that Eu complexes have been successfully introduced into the pores of MCM-48 without disrupting the structure. All the impregnated MCM-48 materials show the typical red luminescence of Eu3+ when excited with a UV lamp. Shifts of the absorption maxima were observed in the DR and fluorescence excitation spectra and will be discussed in relation with guest-host interactions between the organic complex and the silica matrix. The decay profiles of the europium luminescence in the different samples were also measured and discussed. [Copyright &y& Elsevier]

Starting from nitrate aqueous solutions with citric acid and polyethylene glycol (PEG) as additives, Y3Al5O12:Eu (YAG:Eu) phosphors were prepared by a two-step spray pyrolysis (SP) method. The obtained YAG:Eu phosphor particles have spherical shape, submicron size and smooth surface. The effects of process conditions of the spray pyrolysis on the crystallinity, morphology and luminescence properties of phosphor particles were investigated. The emission intensity of the phosphors increased with increasing of sintering temperature and solution concentration due to the increase of the crystallinity and particles size, respectively. Adequate amount of PEG was necessary for obtaining spherical particles, and the optimum emission intensity could be obtained when the concentration of PEG was 0.10 g/ml in the precursor solution. Compared with the YAG:Eu phosphor prepared by citrate-gel (CG) method with non-spherical morphology, spherical YAG:Eu phosphor particles showed a higher emission intensity. [Copyright &y& Elsevier]

High purity KTiOPO4 (KTP) crystals have been grown using a flux method. The quality, SHG efficiency and damage threshold of KTP crystals grown from high purity reagents were compared with those grown from commercial reagents. Experimental results indicate that KTP crystals using a high purity charge contain less impurities and possess higher SHG efficiency and damage threshold than do crystals grown from commercial reagents. It is proposed that decreasing the concentrations of impurities is an effective way of raising the damage threshold for KTP crystals. [Copyright &y& Elsevier]

Large NdP 5 O 14 crystal with dimension of 15 × 25 × 60 mm 3 has been grown by flux method. The spontaneous strains and ferroelastic domain structures have been investigated by high resolution X-ray diffractometry for the first time. The reflection peak separations resulting from the misorientation between matrix domain and ferroelastic domain were observed in the rocking curves for several different reflections. Based on the features of the reflection peak separations, the ferroelastic domain structures were determined. It is found that most of the ferroelastic domains in NdP 5 O 14 are of type-a, while type-b ferroelastic domains only appear in the serious strain regions. Based on the domain structures of NdP 5 O 14 , the reflection peak separations for 802, 402 and 204 reflections were calculated respectively. And the experimental observations are in agreement with the calculations very well. In addition, the spontaneous strain in NdP 5 O 14 was determined to be 0.0082 by measuring the peak separation between two 800 diffraction from the matrix domain and the ferroelastic domain respectively. A detailed discussion on domain structures in the crystal is given in terms of structural and symmetric analyses. [ABSTRACT FROM AUTHOR]

Novel hybrid thin films covalently doped with Eu3+ (Tb3+) have been prepared via direct routes involving co-condensation of tetraethoxysilane and phen-Si in the presence of Eu3+ (Tb3+) by spin-casting and their luminescence properties have been investigated in detail. Lanthanide ions can be sensitized by anchored phenanthroline in hybrid thin films. Excitation at the ligand absorption wavelength (272 nm) resulted in the strong emission of the lanthanide ions i.e. Eu3+ 5D0–7FJ (J=0, 1, 2, 3, 4) emission lines and Tb3+ 5D4–7FJ (J=6, 5, 4, 3) due to the energy transfer from the ligands to the lanthanide ions. [Copyright &y& Elsevier]

By using metal nitrates as starting materials and citric acid as complexing agent, Y3Al5O12 (YAG) and Y3Al5O12:Eu (1 mol%) (YAG:Eu) powder phosphors were prepared by a citrate–gel method. The formation process of YAG and YAG:Eu were investigated by means of XRD, TG–DTA and FT-IR spectra. The purified crystalline phases of YAG and YAG:Eu were obtained at 800 °C. The crystalline YAG:Eu phosphors showed an orange–red emission with 5D0–7F1 (591 nm) as the most prominent group, whose intensity was dependent on the pH value of the starting solution, citric acid content and firing temperature. It has been found that the suitable pH and citric acid/metal ratio are 3 and 2 for obtaining the highest emission intensity, respectively. The emission intensity increases steadily with increasing the annealing temperature from 800 to 1200 °C, and nearly remains constant after 1200 °C. Furthermore, great differences were observed for the lifetimes and the charge transfer band of Eu3+ in crystalline and amorphous states of YAG. [Copyright &y& Elsevier]

Organo-functionalized MCM-41 containing non-covalently linked 1,10-phenanthroline (denoted as Phen-MCM-41) was synthesized by template-directed co-condensation of tetraethoxysilane and the modified phenanthroline (denoted as Phen-Si). XRD, FTIR, UV/VIS spectroscopy as well as luminescence spectroscopy were employed to characterize Phen-MCM-41. No disintegration or loss of the Phen-Si during the solvent extraction procedure could be observed. When monitored by the ligand absorption wavelength (272 nm), the undoped MCM-41 produces a broad band emission centered at 450 nm, whereas europium (III) doped Phen-MCM-41displays the emission of the Eu3+, i.e., 5D0→7FJ (J=0, 1, 2, 3, 4) transition lines due to the energy transfer from the ligands to Eu3+ as well as a broad band emission centered at 442 nm. [Copyright &y& Elsevier]

The europium-substituted heteropolytungstate K13Eu(SiW11O39)2 was successfully assembled into two lipids by LB technique for the first time. X-ray diffraction has shown a well defined lamellar for the LB films. The LB films have been characterized by fluorescence spectra and the characteristic luminescence behaviors were discussed. The ligand–metal charge transfer band could be observed in the spectra of the LB films, which could not be found in that of heteropolytungstate solid. The results of fluorescence spectra indicate the energy could be effectively transferred from ligands to the Eu3+ ions in the LB films and the luminescence efficiency was increased greatly. The influences of various lipids on the luminescence of polyoxometalates were investigated. The various interactions between monolayer and polyanions have different effect on the luminescence properties of europium-substituted heteropolytungstate. [Copyright &y& Elsevier]

Laser beam welding of Ti–24Al–17Nb (at.%) alloy was conducted to investigate the microstructures and the mechanical properties of its joints. The results indicated that the weld microstructure consisted primarily of retained ordered β phase (namely B2 phase) and was independent of the laser welding parameters, while the size and the orientation of the weld solidification structures and then the bend ductility of the joints were related to the welding conditions. The microstructures became coarser and the strains of inducing crack and fracturing decreased as the heat input increased. The fracture occurred in the base metal when the transverse tensile test of the joints was conducted. The tensile strength of the joints was equal to that of the base material and the tensile ductility could reach 12∼17%, which was near to that of the base material. [ABSTRACT FROM AUTHOR]

Abstract. A comparative study of Nd:GdVO[sub 4] and Nd:YVO[sub 4] crystal lasers pumped by a cw diode laser has been conducted at the fundamental wavelengths of 1.06 micro m and 1.34 micro m, as well as when intracavity frequency-doubled to 532 nm and 670 nm, respectively. At these four wavelengths, maximum output powers from the Nd:GdVO[sub 4] crystal laser were 1.27 W, 800mW, 610mW, and 82mW at a diode-launched pump power of 2.9 W. The threshold pump powers were 64 mW, 159 mW, 5 mW, and 12 mW, respectively. All the results obtained from Nd:GdVO[sub 4] were superior to those of Nd:YVO[sub 4], indicating that Nd:GdVO[sub 4] is a more efficient laser crystal than Nd:YVO[sub 4] for diode-pumped solid-state lasers. [ABSTRACT FROM AUTHOR]

[Display omitted] By tuning consistent potentials for bimetal system, the cooperative roles of stacking fault energies (SFEs) such as intrinsic SFE (ISFE) and unstable SFE (USFE) on the dislocation nucleation are comprehensively explored. It reveals that the dislocation nucleation at semi-coherent interface is determined by the misfit dislocations, but the critical yield stress depends strongly on the values of ISFE and USFE that are function of external loadings. To account for such relationship, a modified analytical model is proposed based on the nucleation and propagation of double kinks at the interface, showing good agreement with the simulation results. These results not only resolve the previous inconsistency in the role of stacking faults on plastic deformation but shed light on evaluating the atomistic mechanism according to the synergistic effect between stacking faults and loading schemes. [ABSTRACT FROM AUTHOR]