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[Display omitted] • The Ni-Co base dual-phase superalloy is welded successfully at a broad range of temperatures by hot-compression bonding. • The interfacial healing mechanism of superalloys at different temperatures involves two main recrystallization mechanisms. • The deformation mechanism of primary γ′ phase changes with increasing deformation temperature. • Heterogeneous epitaxial recrystallization is induced by diffusion of Cr elements and DDRX is induced by strain gradients. Hot-compression bonding (HCB) as an advanced technique for preparation of large-size homogenized components is widely applied. Despite the fact that interfacial healing mechanisms during HCB have been extensively investigated, the interfacial healing mechanisms in duplex superalloys still need to be clarified. This article investigates effect of deformation temperature on multiple interface (γ′-γ′, γ-γ, γ-γ′) healing mechanism of dual-phase superalloys. The healing mechanism of γ-γ interface at different temperatures involves a necklace-like distribution of discontinuous dynamic recrystallization (DDRX) grains occupying original interface. With increasing deformation temperature, the healing mechanism of γ′-γ′ interface transforms from DDRX to diffusion bonding due to weakening of strain concentration. Simultaneously, as deformation temperature increases, the deformation mechanism of primary γ′ phase transforms from shearing by stacking fault to dislocation pairs. At deformation temperature 1100 °C, the healing mechanism of γ′-γ interface is heterogeneous epitaxial recrystallization (HERX) induced by primary γ′ phase driven by diffusion of Cr element in dislocation pairs. However, as deformation temperature decreases, healing mechanism in γ′-γ interface transforms into DDRX. Although interfacial healing mechanism is transformed at different deformation temperatures, the synergistic action of different recrystallization mechanisms ensures that mechanical properties of joints reached the same level as those of base material. [ABSTRACT FROM AUTHOR]

Immobilizing catalysts on supports is considered to be one of the promising methods for synthesizing heterogeneous catalysts. Herein, we employed a simple one-pot method to obtain the metalloporphyrin modified carbon nanotubes (ZnTImP-CP/CNTs), using 1,4-bis(bromomethyl)-benzene (BBMB) and zinc 5,10,15,20-tetrakis(4-(imidazole)phenyl)porphyrin (ZnTImP) as monomers. With the Lewis acid sites (Zn-porphyrin) and nucleophilic groups (Br−), this composite material has displayed excellent activity and stability for catalyzing the chemical fixation of CO2 to synthesize value-added cyclic carbonates. The remarkable performance of ZnTImP-CP/CNTs is not only due to the synergy of the Lewis acid and base but also to the large specific surface area. [ABSTRACT FROM AUTHOR]

This paper presents an ultrasonic technique for simultaneous determination of the complete set of acoustical and geometrical properties of a film or a thin layer in a stratified material embedded between two known materials using point-focus ultrasonic spectroscopy, which provides a high lateral resolution. The theoretical model of the two-dimensional spectrum Rt(θ,ω) of the stratified material is calculated as a function of six parameters of the unknown layer: longitudinal and transverse velocities cl, ct, attenuation αl, αt, density ρ, and thickness h, which fully determined the properties of the film. The experimental spectrum Re(θ,ω) can be measured by V(z,t) technique. A two-step algorithm is presented to decompose the searching process of parameters from one six-dimensional to two three-dimensional spaces. The sensitivity of the two-dimensional spectrum to individual properties and its stability against experimental noise are studied. The full set properties of a 250 μm thick stainless steel film and a 930 μm thick SiO2 thin layer of a three layered stratified material immersed in water are determined. The proposed technique used a point-focus transducer, which makes the setup simple and reliable. It allows measurement of the local properties of the film and enables precision material characterization. [ABSTRACT FROM AUTHOR]

This paper presents a minimal mass design approach to the clustered tensegrity structures (CTS). By minimal mass, we mean, for a given clustered tensegrity structure subject to prescribed external loads, the minimal mass is achieved when all the structure members simultaneously fail (buckle or yield). This paper helps to find the lower bound of the required mass of the CTS. Firstly, we introduce the connectivity and clustering definitions through respective matrices and derive the nonlinear clustered tensegrity statics equation in terms of the nodal vector of the structure. Since the mass of each member is in a one-to-one correspondence to its force density (force by unit length), the static equilibrium equations of the CTS with respect to the force density and force vectors are also given. Then, we formulated the mass and gravity of hollow bars and strings subject to buckling and yielding conditions. Finally, a nonlinear optimization algorithm is presented to compute the minimal mass of any CTS with any given external force and topology. We also demonstrate that the traditional tensegrity structure (TTS) is a particular case of the CTS by defining the cluster matrix as an identity matrix. At last, numerical examples are given to validate the CTS minimal mass design approach. The method proposed by this research can be used for the lightweight design of tensegrity, truss, cable nets, membrane structures, etc. • A method to calculate the least necessary mass of any clustered tensegrity. • The traditional tensegrity is a particular case of clustered tensegrity. • The clustering strategy can reduce the number of strings, but the payment is mass. • The method allows hollow/solid bar tensegrity design with/without gravity. [ABSTRACT FROM AUTHOR]

To determine the effect of Ti addition on B removal during silicon refining by directional solidification of Al-30 wt.% Si alloy, five samples with different amount of Ti addition have been studied. The contents of B in primary Si flakes are reduced to less than 1 ppmw with excess Ti addition. An apparent segregation coefficient is used to characterize the B removal during the refining process, which is determined to be 0.0068 with 2000 ppmw Ti addition at a pulling rate of 0.05 mm s −1 . Almost all the B atoms in the Al-Si melt with the excess Ti addition combine with Ti atoms to form TiB 2 particles at the bottom part of the ingot (cold end) before the primary Si growth during directional solidification, resulting in a remarkable B removal rate in the refined primary Si flakes. [ABSTRACT FROM AUTHOR]

To determine the effect of kinetics on P removal in Al-Si-P system, three sets of experiments with different solidification temperature ranges have been carried out. High P removal rates can be confirmed. An apparent segregation coefficient is introduced to characterize the P removal in this Al-Si-P system, which are determined to be 0.0207, 0.00822 and 0.00679, when the cooling rate is 0.556 mK·s −1 and the Si contents in the melt are 39.1, 29.3, 19.4 at.%, respectively. Theoretical P contents in the primary Si phase controlled by thermodynamic factor ( X ¯ P in primary Si T ) and theoretical P contents in the primary Si phase controlled by kinetic factor ( X ¯ P in primary Si K ) are calculated. The results reveal that the kinetic factors have critical influence on P removal at low solidification temperature. [ABSTRACT FROM AUTHOR]

Classification of different mechanisms of angle closure glaucoma (ACG) is important for medical diagnosis. Error-correcting output code (ECOC) is an effective approach for multiclass classification. In this study, we propose a new ensemble learning method based on ECOC with application to classification of four ACG mechanisms. The dichotomizers in ECOC are first optimized individually to increase their accuracy and diversity (or interdependence) which is beneficial to the ECOC framework. Specifically, the best feature set is determined for each possible dichotomizer and a wrapper approach is applied to evaluate the classification accuracy of each dichotomizer on the training dataset using cross-validation. The separability of the ECOC codes is maximized by selecting a set of competitive dichotomizers according to a new criterion, in which a regularization term is introduced in consideration of the binary classification performance of each selected dichotomizer. The proposed method is experimentally applied for classifying four ACG mechanisms. The eye images of 152 glaucoma patients are collected by using anterior segment optical coherence tomography (AS-OCT) and then segmented, from which 84 features are extracted. The weighted average classification accuracy of the proposed method is 87.65 % based on the results of leave-one-out cross-validation (LOOCV), which is much better than that of the other existing ECOC methods. The proposed method achieves accurate classification of four ACG mechanisms which is promising to be applied in diagnosis of glaucoma. [ABSTRACT FROM AUTHOR]

To meet the need of efficient, comprehensive and automatic characterization of the properties of thin layers, a nondestructive method using ultrasonic testing to simultaneously measure thickness, density, sound velocity and attenuation through V ( z , t ) data, recorded by time-resolved acoustic microscopy is proposed. The theoretical reflection spectrum of the thin layer at normal incidence is established as a function of three dimensionless parameters. The measured reflection spectrum R ( θ, ω ) is obtained from V ( z , t ) data and the measured thickness is derived from the signals when the lens is focused on the front and back surface of the thin layer, which are picked up from the V ( z , t ) data. The density, sound velocity and attenuation are then determined by the measured thickness and inverse algorithm utilizing least squares method to fit the theoretical and measured reflection spectrum at normal incidence. It has the capability of simultaneously measuring thickness, density, sound velocity and attenuation of thin layer in a single V ( z , t ) acquisition. An example is given for a thin plate immersed in water and the results are satisfactory. The method greatly simplifies the measurement apparatus and procedures, which improves the efficiency and automation for simultaneous measurement of basic mechanical and geometrical properties of thin layers. [ABSTRACT FROM AUTHOR]

This paper focuses on the design of the optimal scanning mode for the family of scanning probe microscopes. Based on different values of the maximum acceleration (deceleration) rate and maximum speed of X- and Y- axes of the mechanical scanner encountered in practice due to different mechanical design and loads, the design procedure of the optimal fast scanning mode is presented, which is found to be sensitive to the specific parameters of the scanning motion. By utilizing the simultaneous motion of the two axes, the fast raster scanning mode proposed can improve the scanning efficiency by 29% when comparing with the conventional raster (CR) scanning mode, if the scanning speeds of both axes are identical. In addition, the optimal fast mode provided by us has no effects on the image accuracy such as image degradation, image distortion when the efficiency is evaluated. No further difficulties are introduced to the control of the mechanical scanner and the data acquisition process. This optimal scanning mode is useful when the response time of the probe is very fast (such as ultrasonic probe in scanning acoustic microscope (SAM)), and the main limitations are due to the mechanical scanner. By applying different loads for both axes, the experiments with different scanning areas and scanning modes are conducted in a self-developed SAM. Experimental results coincide with the theoretical analysis and confirm the validation of our proposed optimal fast scanning mode and its superiority over the CR scanning mode. SCANNING 36:185-193, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Highlights: [•] Thin layer’s thickness, density, sound velocity, attenuation simultaneous measuring. [•] Investigated dimensionless parameters convergence zones by inverse algorithm. [•] Obtained normal reflection spectrum, thickness, initialization of inverse algorithm. [Copyright &y& Elsevier]

Abstract: A reformulation of the Thomson-Haskell method is presented for calculating the reflection coefficients of multilayer structure immersing in the coupling fluid. Instead of directly multiplying the layer propagator matrix, the new method splits the layer propagator matrix and excursively determines the interface stiffness matrix starting from the bottom half-space with known stiffness. A formulation for the reflection coefficients is derived based on the obtained interface stiffness matrix of the top layer. This scheme can be applied to a single solid layers or layered structures containing both fluid and solid layers. It keeps the simplicity but naturally excludes the exponential growth term and thus can be applied at any frequency range. Its validity and feasibility were experimentally proved by the measurement of the reflection coefficients of a three layered structure of aluminum–glass–aluminum and a sandwiched layer structure of two 250μm stainless plates filled with 100μm deionized water based on the inversion of V(z, t) technique. The result of experiments is consistent with the theoretical calculation. The reformulation of the Thomson-Haskell method offers an efficient and effective solution for calculating the acoustic reflection coefficients of multilayer structures of any configurations. [Copyright &y& Elsevier]

The scanning speed of the two-dimensional stage dominates the efficiency of mechanical scanning measurement systems. This paper focused on a detailed scanning time analysis of conventional raster and spiral scan modes and then proposed two fast alternative scanning modes. Performed on a self-developed scanning acoustic microscope (SAM), the measured images obtained by using the conventional scan mode and fast scan modes are compared. The total scanning time is reduced by 29% of the two proposed fast scan modes. It will offer a better solution for high speed scanning without sacrificing the system stability, and will not introduce additional difficulties to the configuration of scanning measurement systems. They can be easily applied to the mechanical scanning measuring systems with different driving actuators such as piezoelectric, linear motor, dc motor, and so on. The proposed fast raster and square spiral scan modes are realized in SAM, but not specially designed for it. Therefore, they have universal adaptability and can be applied to other scanning measurement systems with two-dimensional mechanical scanning stages, such as atomic force microscope or scanning tunneling microscope. [ABSTRACT FROM AUTHOR]

For inspection of mechanical properties and integrity of critical components such as integrated circuits or composite materials by acoustic methodology, it is imperative to evaluate their acoustic reflection coefficients, which are in close correlation with the elastic properties, thickness, density, and attenuation and interface adhesion of these layered structures. An experimental method based on angular spectrum to evaluate the acoustic coefficient as a function of the incident angle, θ, and frequency, ω, is presented with high frequency time-resolved acoustic microscopy. In order to achieve a high spatial resolution for evaluation of thin plates with thicknesses about one or two wavelengths, a point focusing transducer with a nominal center frequency of 25 MHz is adopted. By measuring the V(z, t) data in pulse mode, the reflection coefficient, R(θ, ω), can be reconstructed from its two-dimensional spectrum. It brings simplicity to experimental setup and measurement procedure since only single translation of the transducer in the vertical direction is competent for incident angle and frequency acquisition. It overcomes the disadvantages of the conventional methods requiring the spectroscopy for frequency scanning and/or ultrasonic goniometer for angular scanning. Two substrates of aluminum and Plexiglas and four stainless plates with various thicknesses of 100 μm, 150 μm, 200 μm, and 250 μm were applied. The acoustic reflection coefficients are consistent with the corresponding theoretical calculations. It opened the way of non-destructive methodology to evaluate the elastic and geometrical properties of very thin multi-layers structures simultaneously. [ABSTRACT FROM AUTHOR]

In this work, metalloporphyrins‐based MOGs were synthesized as precursor to prepare porous coordination polymers (PCPs). Firstly, the carboxyl metalloporphyrins MCPp (M = Zn (II), Co (II), Cu (II), Mn (III)OAc; CPp = 5,10,15,20‐tetra(4‐(3‐carboxy)phenoxy)phenylporphyrin) were synthesized as gelator. Then, the metalloporphyrin‐based MOGs were prepared with MCPp and Al(NO3)3·9H2O by sol–gel method. Moreover, the residual reactants and solvent molecules in MOGs were removed by Soxhlet extraction and supercritical CO2 extraction to get the finial porous coordination polymers. This methodology effectually avoids the collapse of frame construction. Compared with the reference material prepared by the oven‐dry method, these PCPs exhibit much higher BET surface ranging from 398 to 439 m2 g−1. The PCPs were carefully characterized by FT‐IR, UV–vis, SEM, TEM and PXRD, and exhibit excellent catalytic activities and stabilities for the oxidation of ethylbenzene. [ABSTRACT FROM AUTHOR]

Ustilaginoidea virens is the causal agent of rice false smut, which has recently become one of the most important rice diseases worldwide. Ustilaginoidins, a major type of mycotoxins produced in false smut balls, greatly deteriorates grain quality. Histone acetylation and deacetylation are involved in regulating secondary metabolism in fungi. However, little is yet known on the functions of histone deacetylases (HDACs) in virulence and mycotoxin biosynthesis in U. virens. Here, we characterized the functions of the HDAC UvHOS3 in U. virens. The ΔUvhos3 deletion mutant exhibited the phenotypes of retarded growth, increased mycelial branches and reduced conidiation and virulence. The ΔUvhos3 mutants were more sensitive to sorbitol, sodium dodecyl sulphate and oxidative stress/H2O2. ΔUvhos3 generated significantly more ustilaginoidins. RNA‐Seq and metabolomics analyses also revealed that UvHOS3 is a key negative player in regulating secondary metabolism, especially mycotoxin biosynthesis. Notably, UvHOS3 mediates deacetylation of H3 and H4 at H3K9, H3K18, H3K27 and H4K8 residues. Chromatin immunoprecipitation assays indicated that UvHOS3 regulates mycotoxin biosynthesis, particularly for ustilaginoidin and sorbicillinoid production, by modulating the acetylation level of H3K18. Collectively, this study deepens the understanding of molecular mechanisms of the HDAC UvHOS3 in regulating virulence and mycotoxin biosynthesis in phytopathogenic fungi. [ABSTRACT FROM AUTHOR]

Two carboxyl‐functional Mn (III)–porphyrins reacted with two metal nitrates (Cr (NO3)3·9H2O and Al (NO3)3·9H2O) via solvothermal method, respectively, to produce four metalloporphyrin‐based metal organic gels (MOGs). To remove unreacted metal salts and DMF, the gels were dealt with Soxhlet extraction and supercritical CO2. Finally, four desired porous coordination polymers (PCPs) were prepared. The newly synthesized PCPs were characterized by FT‐IR, UV–vis, SEM, and TEM. The contrast experiments show these PCPs possess good catalytic activities for the cycloaddition reactions of epoxide and CO2 under mild and solvent‐free conditions using tetrabutylammonium bromide (TBAB) as co‐catalyst. [ABSTRACT FROM AUTHOR]

Clarifying the response of soil microbial communities to vegetation restoration is essential to comprehend biogeochemical processes and ensure the long-term viability of forest development. To assess the variations in soil microbial communities throughout the growth of Pinus armandii plantations in the karst region, we utilized the “space instead of time” approach and selected four P. armandii stands with ages ranging from 10 to 47 years, along with a grassland control. The microbial community structure was determined by conducting Illumina sequencing of the 16 S rRNA gene and the ITS gene, respectively. The results demonstrated that afforestation with P. armandii significantly influenced soil microbial communities, as indicated by notable differences in bacterial and fungal composition and diversity between the plantations and the control. However, soil microbe diversity did not display significant variation across stand ages. Moreover, the bacterial community exhibited higher responsiveness to age gradients compared to the fungal community. Soil physicochemical factors play a critical role in elucidating microbial diversity and community composition variations during restoration processes. TN, AN, TP, AP, SOC, AK, and pH were the most significant influencing factors for the composition of bacterial community, while TC, SOC, pH, and TCa were the most significant influencing factors for the composition of fungal community. Our findings indicate substantial changes in soil bacterial and fungal communities across successive stages of development. Additionally, the changes in dominant bacteria and fungi characteristics across the age gradient were primarily attributed to variations in the prevailing soil conditions and chemical factors. [ABSTRACT FROM AUTHOR]

Priority conservation areas are the key areas of biodiversity maintenance and ecosystem conservation. Based on a Maxent model, this study predicted the potential distribution of Pseudotsuga sinensis under the current climate and future climate change scenarios in Guizhou province, and then, assessed three kinds of priority conservation area under climate change. The results were as follows: (1) The AUC (Area Under the Curve) values showed excellent prediction accuracy of the model. (2) The areas of the potential habitats of P. sinensis forests under the current climate and future climate change scenarios were 22,062.85 km2 and 18,395.92 km2, respectively. As for their spatial distribution, the potential habitats of P. sinensis forests were distributed in the Bijie, Zunyi, Tongren, Liupanshui and Xingyi regions under the current climate, and in the Kaili region, in addition to the above-mentioned cities, under future climate change scenarios. (3) The total area of priority conservation areas under climate change was 25,350.26 km2. The area of the predicted sustainable potential habitats was 15,075.96 km2, of the vulnerable potential habitats was 7256.59 km2 and of the derivative potential habitats was 3017.71 km2. [ABSTRACT FROM AUTHOR]

Solvent refining of Al–Si–B alloy samples with different amounts of Ti additions are carried out, which confirms a high B removal rate with excessive Ti addition. An apparent segregation coefficient is introduced to characterize the segregation between primary Si and Al–Si melt, which are determined to be 0.0471 with 575 ppma Ti addition at the cooling rate of 50 mK·s −1 . Temperature dependence of X Ti ( l ) in Al - Si melt X B ( l ) in Al - Si melt 2 , individual Ti and B contents in the Al-29.3at.%Si melt from 1323 to 1123 K are calculated. It proves that TiB 2 precipitates before the primary Si formation, which causes the decrease of B contents in the Al–Si melt and contributes to the high B removal rate. Moreover, BSE/SEM observation of TiB 2 and (Al,Ti,Si) phase indicates a new competitive reaction mechanism in Al–Si–Ti–B system. [ABSTRACT FROM AUTHOR]

Background and objectives Angle closure glaucoma (ACG) is an eye disease prevalent throughout the world. ACG is caused by four major mechanisms: exaggerated lens vault, pupil block, thick peripheral iris roll, and plateau iris. Identifying the specific mechanism in a given patient is important because each mechanism requires a specific medication and treatment regimen. Traditional methods of classifying these four mechanisms are based on clinically important parameters measured from anterior segment optical coherence tomography (AS-OCT) images, which rely on accurate segmentation of the AS-OCT image and identification of the scleral spur in the segmented AS-OCT images by clinicians. Methods In this work, a fully automated method of classifying different ACG mechanisms based on AS-OCT images is proposed. Since the manual diagnosis mainly based on the morphology of each mechanism, in this study, a complete set of morphological features is extracted directly from raw AS-OCT images using compound image transforms, from which a small set of informative features with minimum redundancy are selected and fed into a Naïve Bayes Classifier (NBC). Results We achieved an overall accuracy of 89.2% and 85.12% with a leave-one-out cross-validation and 10-fold cross-validation method, respectively. This study proposes a fully automated way for the classification of different ACG mechanisms, which is without intervention of doctors and less subjective when compared to the existing methods. Conclusions We directly extracted the compound image transformed features from the raw AS-OCT images without any segmentation and parameter measurement. Our method provides a completely automated and efficient way for the classification of different ACG mechanisms. [ABSTRACT FROM AUTHOR]

The design and synthesis of efficient heterogeneous catalysts for catalytic conversion of CO2 are an important challenge. The novel zinc porphyrin polymer reported herein, [ZnPy+CPP‐BTA]I−, is synthesized from trans‐A2B2 porphyrin precursor 5,15‐(4‐carboxyphenyl)‐10,20‐(pyridyl)‐porphyrin (PyCPP) and 1,2,4,5‐benzenetetramine tetrahydrochloride (BTA), employing a sequential post‐synthetic methylation and metalation strategy. The newly synthesized zinc porphyrin polymer was well characterized by Fourier transform infrared spectroscopy (FT‐IR), Ultraviolet–visible spectroscopy (UV–vis), scanning electron microscope (SEM), transmission electron microscope (TEM), thermal gravimetric analysis (TGA), and X‐ray photoelectron spectroscopy (XPS). As bifunctional heterogeneous catalyst incorporated zinc porphyrin and nucleophile I−, [ZnPy+CPP‐BTA]I− shows good catalytic activity and recyclability for the cycloaddition reactions of epoxides and CO2 under lower CO2 initial pressure and cocatalyst‐free conditions. [ABSTRACT FROM AUTHOR]

Glaucoma is an eye disease where a loss of vision occurs as a result of progressive optic nerve damage usually associates with high intraocular pressure. A subtype of glaucoma called primary angle-closure glaucoma (PACG) has been observed to be the result of one or more mechanisms such as Pupil block, Plateau iris, Peripheral iris roll, and Lens in the anterior segment of the eye. Reliable features in anterior segment images are important for determining the specific mechanisms involved in PACG. In this paper, first the discriminant features are selected by several feature selection algorithms in the context of PACG detection based on anterior segment optical coherence tomography (AS-OCT) images, and then a novel criteria is proposed to further select more reliable features. Our approach is based on selecting the top-ranked features in each algorithm and its rank combination for selection of the best features. Compared with the features selected by the individual feature selection methods, the features selected by our method achieves the best performance in terms of the accuracy of classification of the four PACG mechanisms by using AdaBoost classifier. [ABSTRACT FROM AUTHOR]

Mullite fibers composite silica‐based ceramic cores were successfully prepared by injection molding. The effects of mullite fibers on the mechanical and thermal properties of ceramic cores were investigated. The results indicated that the linear shrinkage was significantly decreased and the porosity was gradually increased with the increase of mullite fibers. In addition, the flexural strength for the room temperature and the simulated casting temperature of 1500°C was increased to a maximum value when the content of mullite fibers was about 1 wt.%, and then decreased with the increase of mullite fibers. The mullite fibers of 1 wt.% presented excellent mechanical properties with a linear shrinkage of.65%, a porosity of 6.96%, and a flexural strength of 17 MPa at room temperature and 34.83 MPa at the simulated casting temperature of 1500°C. Besides, the change in microstructure and properties in various contents of mullite fibers were analyzed. [ABSTRACT FROM AUTHOR]

Ma, Y.; Wang, Q.; Bai; X., and Chen, G., 2020. Marine Economic Prediction Based on Mathematical Models. In: Li, L. and Huang, X. (eds.), Sustainable Development in Coastal Regions: A Perspective of Environment, Economy, and Technology. Journal of Coastal Research, Special Issue No. 112, pp. 224-227. Coconut Creek (Florida), ISSN 0749-0208. The mathematical forecasting model has the characteristics of low data requirements, but high accuracy and good effect on medium and short-term forecasts. Its application range is very wide. Based on the marine economic data from 2010 to 2014, establish the mathematics of the marine economic added value. The model was tested and verified to prove that the model was available, and the marine economic added value was predicted. By comparing the predicted value with the initial value data, it was found that the added value did not match the increase of the marine production added value. The rate of increase in value is slower than that of marine production, which shows that when attracting marine economic talents, capital, technology, etc., the corresponding marine scientific research, education, and management services are not paid enough attention. Neither the absolute amount nor the relative proportion does not match. Finally, conclusions and suggestions are given. [ABSTRACT FROM AUTHOR]

Abstract The accuracy of debugging information is crucial for source level debugging. However the debugging information may be inaccurate after sophisticated optimizations if the target program is compiled into native code. Hence, the efficiency of diagnosing software is affected due to inaccurate debugging information. To address the issue, we propose Debugopt, a framework for debugging fully optimized natively compiled programs using multistage instrumentation. At compile time, Debugopt generates unoptimized programs with accurate debugging information and optimized programs. At debugging time, Debugopt dynamically replaces the execution of optimized programs with unoptimized programs. Debugopt is implemented on multiple architectures, including x86-32, x86-64, armv7 and mips3. Debugopt's overhead is small during normal execution on a large range of benchmarks. [ABSTRACT FROM AUTHOR]

Aiming to develop an effective solidification purification process by Al-Si alloy refining method, experiments under rotating electromagnetic field (REMF) with varying frequencies have been carried out. High B/P removal rates under REMF can be confirmed. A primary Si-rich layer formed near the side surface of the sample, while the interior of the sample is mainly eutectic Si/Al. Effect of varying frequency of REMF on alloy structure, size of the primary Si flakes and B/P contents in the primary Si flakes are studied. An apparent segregation coefficient is introduced to describe refining process. The apparent segregation coefficients of B and P are determined to be 0.12 and 0.06 respectively when the frequency of REMF and the cooling rate are10 Hz and 50 mK s −1 respectively. [ABSTRACT FROM AUTHOR]

Litter inputs are expected to have a strong impact on soil N2O efflux. This study aimed to assess the effects of the litter decomposition process and nutrient efflux from litter to soil on soil N2O efflux in a tropical rainforest. A paired study with a control (L) treatment and a litter-removed (NL) treatment was followed for 2 years, continuously monitoring the effects of these treatments on soil N2O efflux, fresh litter input, decomposed litter carbon (LCI) and nitrogen (LNI), soil nitrate (NO3−-N), ammonium (NH4+-N), dissolved organic carbon (DOC), and dissolved nitrogen (DN). Soil N2O flux was 0.48 and 0.32 kg N2O-N ha−1 year−1 for the L and NL treatments, respectively. Removing the litter caused a decrease in the annual soil N2O emission by 33%. The flux values from the litter layer were higher in the rainy season as compared to the dry season (2.10 ± 0.28 vs. 1.44 ± 0.35 μg N m−2 h−1). The N2O fluxes were significantly correlated with the soil NO3−-N contents (P < 0.05), indicating that the N2O emission was derived mainly from denitrification as well as other NO3− reduction processes. Suitable soil temperature and moisture sustained by rainfall were jointly attributed to the higher soil N2O fluxes of both treatments in the rainy season. The N2O fluxes from the L were mainly regulated by LCI, whereas those from the NL were dominated jointly by soil NO3− content and temperature. The effects of LCI and LNI on the soil N2O fluxes were the greatest in the 2 months after litter decomposition. Our results show that litter may affect not only the variability in the quantity of N2O emitted, but also the mechanisms that govern N2O production. However, further studies are still required to elucidate the impacting mechanisms of litter decomposition on N2O emission from tropical forests. [ABSTRACT FROM AUTHOR]

A focal probe is used for the acoustic measurement of a thin layer of a material with unknown sound velocity. This is now possible, because an algorithm, based on the focused ray model, has been found. However, there are still several problems such as the assumption that the half-aperture angle equals the incident angle, the identification of the longitudinal-wave focus, and the composition of the signal. In this work, we study the multi-mode wave focus numerically and experimentally to identify the focused longitudinal waves. A theoretical multilayered focusing model has been introduced based on geometrical acoustics. In addition, a phase differentiation theory is proposed to find the incident angle for the focus of the tilted rays, which is referred to as maximum half-aperture angle in other studies. The V ( z , t ) curve of a single layer, with a thickness of 1.5 mm and 2.0 mm, and a multi-layer are obtained using vertical translational movement. Both thickness and sound velocity are derived from the curve simultaneously. Our single layer experiments show that it is possible to focus multimode waves. The single and multi-layer experiments confirm the multi-layered focused ray model and phase differentiation theory. Furthermore, experiments are conducted to analyze the measured results. [ABSTRACT FROM AUTHOR]

A bond-based peridynamic approach was applied to investigate the fragmentation of ice cover by blast loads of an underwater explosion. A modified elastic micromodulus was proposed in peridynamics, which can describe the long-range force varying with distance between two particles. The elastic-brittle constitutive model was implemented in numerical model considering different compressive and tensile strength of ice. A blast loading generated by underwater explosion was analyzed, in which the effects of fluid-solid coupling and liquid jets were taken into account. In addition, the failure criterion is defined based on fracture toughness. The simulation results show a good agreement with the experimental data. Furthermore, the parameters that influence the fracture radius of the ice cover were also discussed. [ABSTRACT FROM AUTHOR]

This paper investigates a numerical approach to predict the ice loads on a conical structure through simulating the failure process of level ice sheet using the discrete element method (DEM). In the simulation, the level ice sheet is modeled with the bonded spherical particles, which can be de-bonded based on the bonding-breaking criteria. The ice sample compression and three-point bending tests are used to set up the relationship between the ice strengths, i.e. compression strength and flexural strength, and the bonding strengths in the DEM model; the sensitivity of particle size, normal and shear bonding strength, normal and shear contact stiffness are analyzed. The ice loads on narrow conical structures with different cone angles are simulated using the DEM model. Meanwhile, a comparison between numerical results and the ISO ice force standard is carried out. In addition, the interaction between level ice and multi-legs conical structure is simulated to study the shadowing effect. [ABSTRACT FROM AUTHOR]

The influence of Sn doping on improvement of minority carrier lifetime (MCL) of Fe contaminated directionally solidified p-type multi-crystalline Si ingots is studied. The macrostructure and resistivity distribution of the Si ingots indicate that no significant difference exists with and without Sn doping. The average MCL increase by 26.2%, 31.8%, 8.1% with 20 ppmw, 40 ppmw, 60 ppmw Sn doping, respectively. The MCL was improved evidently due to the reduction of formation of interstitial Fe, FeB. The doping of Sn promotes formation of vacancies, which also contributes to passivation of interstitial Fe and FeB. A calculation of constitutional supercooling is carried out, which shows that Fe have great influence on the solidification interface stability, and Sn have little influence on the interface stability. [ABSTRACT FROM AUTHOR]

During a disruption, plasma electromagnetic energy usually damages tokamak devices severely. Thus, this paper presents a five-part energy processing system (EPS) to dispose this energy. The five parts of the EPS are as follows: the metal oxide varistors employed to limit overvoltage and to absorb energy, the resistor module applied to consume energy, the pulse capacitor module used to store energy, the inverter module used for energy feedback, and the controller. These parts are described, and their key design features are introduced. The influence of different capacitances and resistances on the amount of energy transferred is investigated. The simulation results obtained by the Power Simulation program are given. The experimental and simulation results show that about 20%–30% of the total plasma electromagnetic energy can be transferred out of the tokamak device and effectively disposed by the EPS during the disruptions in the Joint Texas Experimental Tokamak (J-TEXT) tokamak. Moreover, the loop voltage during a disruption can be inhibited and decreases about 40%. [ABSTRACT FROM AUTHOR]

Abstract: T92/Super304H dissimilar steel weld joints, fabricated through a gas tungsten arc welding (GTAW) technique using a Ni-based welding wire of ERNiCrMo-3, were aged at 650°C for time up to 3000h. Microstructures, fractographies and mechanical properties of the joints were then investigated. The results show that as the aging time increased, in the T92 side heat-affected zone (HAZ) and base metal (BM), the second-phase particles aggregate and coarsen along the austenite grain boundaries/in the austenite grains. In the Super304H side HAZ and BM, the growth of the austenite grains and that of the second-phase particles are slight. The fracture positions of the aged joints are always in the T92 BM. The tensile strengths and the hardness values of the joints drop firstly, then rise, and finally tend to be stable. The impact toughness values of the joints are monotonously decreases with the ageing time. [Copyright &y& Elsevier]

Abstract: After short-term tensile test at 848–923K, microstructures, fractographies and fractural mechanisms of the T92/TP347H dissimilar steel weld joints were studied. An equation of the creep rupture strength related to the short-term tensile strength of the joints was firstly derived based on the Goldenberg model [1]. In the high-temperature tensile process, the fracture location of the joints is all in the T92 side fine grained heat affected zone (FGHAZ); however, the fracture mechanism of the joints is changed from a mixed mode (normal plus shear) to a shear mode as the testing temperature risen, which was explained in terms of the stress tri-axiality theory. Moreover, an equation of the creep rupture strength of the weld joints was derived, and then the creep rupture strength of the joints was doped out, . It indicates that the joints have a high reliability when used in the USC power units. [Copyright &y& Elsevier]

Abstract: Glutathione peroxidase (GPx, EC 1.11.1.9) is a key enzyme involved in scavenging of reactive oxygen species in biological system. For developing an efficient GPx-like antioxidant, catalytically necessary amino acid derivatives which located near the GPx active center were prepared as functional monomers. Via predetermined imprinting with substrate glutathione (GSH), a polymer-based GPx mimic with a similar structure of catalytic center of natural GPx was developed, and it demonstrated high-catalytic efficiency and substrate specificity. The imprinting polymer (I-PEM) exhibits GPx-like activity about three times higher than that of 2-SeCD, a cyclodextrin-based GPx mimic. The detailed studies on kinetics revealed that not only the substrate binding but also positional arrangement of reacting groups contribute significantly to the catalytic efficiency of the peroxidase model. [Copyright &y& Elsevier]

Abstract: An allosteric hydrolase model (1) with cooperativity between a metal center and an allosteric site has been constructed through supramolecular assembly of an adamantanyl guanidinium and a copper (II) complex of tris(2-aminoethyl)amine modified cyclodextrin (tren-CD). The structure of the supramolecular inclusion has been determined by 1H NMR and selective NOESY measurement. Furthermore, the allosteric role of the guanidinium group was unambiguously demonstrated by the catalytic behaviors of the allosteric model 1, the kinetics studies for the allosteric model revealed that the allosteric guanidinium group strongly influences catalytic behaviors of the supramolecular catalyst in the cleavage of 4,4′-dinitrodiphenyl carbonate (DNDPC). For example, the turnover number k cat of catalyst 1 was 20min−1 and the second-order rate constant of 14,080M−1 min−1 was observed for the hydrolysis of DNDPC, catalyst 1 exhibits higher activity than catalyst 2 without an allosteric site, and its activity is similar to that for copper (II) complex of tris(2-aminoethyl)amino-cyclodextrin (Cu-tren-CD) which possesses a free cavity as a substrate binding site. Obviously, this result revealed that the presence of guanidinium group led to change of the catalytic mechanism and efficiency in the hydrolytic process. [Copyright &y& Elsevier]

• Comparing tropical rainforest (TRF) to rubber plantation (RP) emissions, CH 4 sink decreased and CO 2 emission was similar. • Leaf area index and soil water content mainly influences soil CO 2 and CH 4 emissions in RP respectively. • Soil water content, soil temperature, and dead fine roots were the most important factors of soil CO 2 and CH 4 emissions in TRF. • Soil temperature and fine root growth explained the difference in soil CO 2 and CH 4 between TRF and RP. Soil CO 2 (a) and CH 4 (b) fluxes in tropical rainforest (black circles) and rubber plantation (open circles) at Xishuangbanna, Southwest China. [Display omitted] [ABSTRACT FROM AUTHOR]