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Abstract Offshore wind power foundations are known to bear complex loadings, not only vertical loading V induced by self-weight, but also horizontal loadings H induced by wind, wave and current, and the bending loading M transferred from superstructure. In this paper a framework for evaluating the bearing capacity of the foundations is presened and the bearing characteristics of offshore wind power foundation under combined horizontal, vertical and bending loadings are analyzed. The bearing capacity of offshore wind power foundation under unidirectional horizontal, vertical and bending loadings is examined, and the relationship between the ultimate bearing capacity and the ratio of diameter to length of pile foundation is obtained. Based on the side-swipe method, the envelope of bearing capacity and failure mode of offshore wind power foundation in V - H , V - M , H - M loading space and V - H - M loading space are studied in details, and the parameter analysis of the envelope of foundation bearing capacity in different loading space are discussed. Finally, a simple and practical method is proposed to judge the stability of the offshore wind power and the seabed. A verification example reveals that the estimates of the presented framework shows good agreement with observations. [ABSTRACT FROM AUTHOR]

Discusses Lewis acid-catalyzed hydrostannation of acetylenes. Regio- and stereoselective trans-addition of tributyltin hydride and dibutyltin dihydride; Use of nonpolar solvents for obtaining high stereoselectivity and chemical yield; Reactions of internal acetylenes.

• The photo-sensitive micellar systems have improved biodegradability and less toxicity. • Photo-responsive systems based on mixed cationic/anionic surfactants are superior. • Mixed photo-sensitive additives have the advantages of both the constituent additives. • Photo-responsive systems are based on low concentrations of surfactants and additives. A method to construct photo-responsive wormlike micellar systems with high photo-responsive efficiency and strong photo-responsive ability and reduced impact on the environment by mixed cationic/anionic surfactants and mixed photo-sensitive additives has been proposed. For this purpose, a cleavable cationic ester-containing gemini surfactant, N , N '-bis(2-(dodecanoyloxy)ethyl)- N , N , N ', N '-tetramethyl-1,3-propane diammonium dibromide (C 12 DEG 3), and five anionic biocompatible carboxylate surfactants, have been selected. The mixed photo-sensitive additives are composed of sodium trans -ortho-methoxycinnamate (trans -NaOMCA) and sodium trans -cinnamate (trans -NaCA). The mixed cationic/anionic surfactants are superior to the single cationic surfactant C 12 DEG 3 in constructing UV light-responsive wormlike micellar systems due to their stronger self-assembly ability. The molecular structure of anionic surfactant, such as the length of hydrophobic tail, the introduction of the N-methylated amide group between the hydrophobic tail and carboxylate headgroup, and the number of hydroxyl group in bile salts, is important factor influencing the self-assembly ability of the mixed systems. For single C 12 DEG 3 or the mixed cationic/anionic surfactants, the mixed photo-sensitive additives have the advantages of both trans -NaCA and trans -NaOMCA. The fast reaction rate of the trans -to- cis photoisomerization of NaOMCA leads to the high photo-responsive efficiency of the wormlike micellar systems. The addition of t rans -NaCA promotes the growth of wormlike micelles and leads to larger difference between viscosities before and after UV irradiation, demonstrating higher photo-responsive ability. The experimental results reveal that the UV light induced trans -to- cis isomerization of NaOMCA is the main reason inducing the microstructural transition from wormlike micelles to coexistence of spherical and short rodlike micelles and thus causing reduction in shear viscosities by 3–4 orders of magnitude. [ABSTRACT FROM AUTHOR]

CoCrCuFeMnNix (x = 0.5, 1.0, 1.5, 2.0 mol, named Ni0.5, Ni1.0, Ni1.5, and Ni2.0, respectively) high‐entropy alloys (HEAs) were prepared by powder metallurgy. The effects of Ni content on its microstructure and corrosion resistance in a 3.5% NaCl solution were studied. The HEAs with low Ni content consisted of FCC1 primary phase, FCC2 secondary phase, and a few σ phases. While the Ni2.0 alloy was composed of the FCC phase and a small amount of σ phase. The results of polarization corrosion in 3.5% NaCl solution show that the increase of Ni content led to the increase of corrosion potential of the alloy and the decrease of corrosion current density and average corrosion rate. Among them, Ni2.0 alloy had the best corrosion resistance. The electrochemical impedance spectroscopy analysis showed that the increase in Ni content promoted the increase of the polarization resistance of the alloy RCPE and the thickness of the passive film, thus improving the corrosion resistance of the alloys. [ABSTRACT FROM AUTHOR]

A quantitative multi-phase-field model for non-isothermal and polycrystalline solidification was developed and applied to dilute multicomponent alloys with hexagonal close-packed structures. The effects of Lewis coefficient and undercooling on dendrite growth were investigated systematically. Results show that large Lewis coefficients facilitate the release of the latent heat, which can accelerate the dendrite growth while suppress the dendrite tip radius. The greater the initial undercooling, the stronger the driving force for dendrite growth, the faster the growth rate of dendrites, the higher the solid fraction, and the more serious the solute microsegregation. The simulated dendrite growth dynamics are consistent with predictions from the phenomenological theory but significantly deviate from the classical JMAK theory which neglects the soft collision effect and mutual blocking among dendrites. Finally, taking the Mg-6Gd-2Zn (wt.%) alloy as an example, the simulated dendrite morphology shows good agreement with experimental results. [ABSTRACT FROM AUTHOR]

Cold tolerance and the green period are key traits in the breeding of zoysiagrass (Zoysia Willd.). Identifica-tion of molecular markers associated with cold tolerance and the green period of zoysiagrass will contribute to efficient selection of elite cultivars. These two traits were measured in 96 zoysiagrass accessions in 2004 and 2005-2006, respectively. The mapping population was screened with 29 pairs of simple sequence repeat (SSR) primers and 54 pairs of sequence-related amplified polymorphism (SRAP) primers. A multi-loci in silico mapping approach implemented with an empirical Bayes method was applied for association mapping of cold tolerance and green period. We detected 254 SSR polymorphic loci and 338 SRAP polymorphic loci, among which three SSR loci (Xgwml31-3B-187, Xgwm469-6D-194 and Xgwm234-5B-244) and one SRAP locus (MellEm7-406) were significantly associated with cold tolerance with effect values of 57.83%, 38.05%, 36.92% and 37%, respectively. Three SSR loci (Xgwml32-6B-225, Xgwml 11-7D-34 and Xgwml02-2D-97) and two SRAP loci (Mel9Em5-359 and Mel6Em8-483) were significantly associated with the green period with effect values of 79.54%, 62.59%, 99.04%, 49.01% and 82.57%. These markers will be useful for genetic improvement of the cold tolerance and green period of zoysiagrass by marker-assisted breeding. [ABSTRACT FROM AUTHOR]

Three ester-containing gemini surfactants (CmDEGs) were used to construct UV-responsive micellar systems with sodium trans-ortho-methoxycinnamate (trans-NaOMCA) as photo-sensitive additive. The effect of tail-chain length and spacer chain length on the UV-responsive ability was preliminarily explored. Longer tail chain and shorter spacer chain are favorable factors for enhancing UV-responsive ability. The addition of trans-NaOMCA into N,N′-bis(2-(dodecanoyloxy)ethyl)-N,N,N′,N′-tetramethyl-1,3-propane diammonium dibromide (C12DEG3) aqueous solution leads to a peak in zero-shear viscosity (η0) versus composition curve, and its further addition induces aqueous two-phase separation. For the C12DEG3/trans-NaOMCA/H2O mixed micellar systems, the UV responsiveness of significant decrease in η0 ascribes to microstructural transitions arising from the changes in counterion binding modes due to the trans-cis photoisomerization of NaOMCA. In comparison with the gemini surfactant 12-3-12, C12DEG3 has ester groups introduced in its tail chains. The introduction of ester groups leads to a significant effect on enhancing the photo-responsive ability in viscosity decrease of the constructed UV-responsive micellar systems. Furthermore, the effect of the addition of an amino acid–based surfactant sodium lauroylglutamate (SLGlu) into the C12DEG3/trans-NaOMCA/H2O mixed system on the UV-responsive behaviors was explored. In addition to UV-induced significant decrease in η0 and phase transition from aqueous two-phase systems (ATPS) to isotropic single-phase systems, the addition of SLGlu can also cause UV-induced increase in η0 and lead to richer UV-induced phase transition behaviors. The reason leading to these differences due to the presence of SLGlu was discussed based on 1H NMR spectra, molecular dynamics (MD) simulation, and molecular electrostatic potential (MEP) analysis. [ABSTRACT FROM AUTHOR]

Cynodon dactylon and Zoysia japonica are two important warm-season turfgrass species with multiple utilizations. Genetic transformations of Cynodon dactylon and Zoysia japonica are extremely difficult, which severely restrict the gene functional studies and molecular breeding research of the two grasses. By contrast, virus-induced gene silencing (VIGS) presents an effective and rapid alternative method to create targeted gene knock-outs for gene functional studies in plants. In this study, we tested the efficiency of modified rice tungro bacilliform virus (RTBV) vector in silencing Cynodon dactylon and Zoysia japonica phytoene desaturase ( PDS ) gene through agroinfiltration. The agroinfiltrated leaves of two Cynodon dactylon and two Zoysia japonica cultivars all showed white streaks typical for PDS gene silencing at 21 days post agroinfiltration. In Cynodon dactylon and Zoysia japonica plants displaying white streak leaf symptoms, PDS gene expression in leaves were all significantly lower than that of control and mock-infected plants. These results indicated that RTBV-VIGS system is efficient in Cynodon dactylon and Zoysia japonica . [ABSTRACT FROM AUTHOR]