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The flow losses owing to friction and unstable flow patterns in Francis turbines will cause a drop in their efficiency. The traditional approach to evaluating the hydraulic losses of Francis turbine via the pressure drop cannot determine the exact locations at which the high energy loss occurs. In this paper, a full analysis for flow losses in a Francis turbine with the entropy production method has been implemented. Firstly, the prediction of hydraulic efficiency between entropy production theory and the model test is compared. Secondly, distribution of entropy production in different parts and flow components is analyzed. Finally, detailed distribution of local entropy production rate (LEPR) in spiral casing, stay/guide vanes, runner and draft tube is investigated. It is found that hydraulic losses of the turbine are closely related to flow separation and the vortex motion as well as backflow. Meanwhile, draft tube accounts for the greatest proportion of entropy production followed by the runner. It is concluded that the entropy production method adopted in this paper can be feasible to explore where the energy dissipation happens and how it is distributed in Francis turbine passage under different operating conditions within a certain reasonable range of error.

The Qianlishan complex, located in Hunan Province of South China, is closely associated with intense W-dominated polymetallic mineralization. The Qianlishan complex is composed of three phases: the main-phase porphyritic and equigranular granites, granite porphyry, and mafic dykes. Geochronologically, the zircon U-Pb dating results show that the porphyritic and equigranular granites have ages of approximately 159 and 158 Ma, respectively, similar to those of mafic dykes (approximately 158 Ma), while the granite porphyry was formed later at approximately 145 Ma. Geochemically, the mafic dykes are characterized by calc-alkaline high-Mg andesite (HMA) with high MgO, TiO2, Mg#, and CA/TH index. They exhibit significantly depleted &epsilon, Nd(t) and &epsilon, Hf(t) with high Ba/La, La/Nb, and (La/Yb)N, indicating that they formed from mixing melts of depleted asthenospheric mantle and metasomatized subcontinental lithospheric mantle (SCLM). The main-phase granites are peraluminous and are characterized by high SiO2, low (La/Yb)N ratios, and relative depletion in Ba, Sr, Ti, and Eu. They also display negative correlations between La, Ce, Y, and Rb contents, suggesting that they are highly fractionated S-type granites. Furthermore, they show high &epsilon, Hf(t), CaO/Na2O ratios, HREE, and Y contents, indicating that they were produced by parental melting of ancient basement mixed with mantle-derived components. In contrast, the granite porphyry shows A-type signature granites, with higher &epsilon, Hf(t) and CaO/Na2O ratios than the main-phase granites but similar Zr/Nb and Zr/Hf ratios to the mafic dykes, suggesting that they are the products of partial melting of a hybrid source with ancient basement and the mafic dykes. We thus infer that the slab roll-back led to generation of Qianlishan back-arc basalt and HMA and further triggered the formation of the Qianlishan granite.

Aims This study aims to compare the proportion of peripheral blood T lymphocyte subsets and related blood cell and bone marrow cytology indexes between patients with aplastic anemia (AA) and hypoplastic myelodysplastic syndrome (hypo-MDS), and investigate the clinical identification significance. Materials and methods A total of 41 patients with AA and 46 patients with hypo-MDS were collected, and the proportions of peripheral blood T lymphocyte subsets, CD3− CD16/CD56+ NK cells, CD3+ CD57+ T-LGL cells and CD19+ B lymphocytes were detected by flow cytometry. Key findings The CD4+/CD8+ ratio decreased in the AA and hypo-MDS groups, and the difference was statistically significant when compared with that in the control group (P 0.05). The proportions of CD3− CD16/CD56+ NK cells and CD3+ CD57+ T-LGL cells in the hypo-MDS group were distinctly higher than those in the AA group (P Significance Changes of T lymphocyte subsets and the proportions of large granular lymphocytes and B lymphocytes can be utilized as indexes in the differential diagnosis between AA and hypo-MDS.

The precessing vortex core in the draft tube of Francis turbine is investigated using entropy production method. The high-fidelity Delayed Detached Eddy Simulation (DDES) method with SST k-ω turbulence model is used to acquire the entropy dissipative components of the flow, and the Q-criterion is selected to evaluate the vortex cores inside the draft tube under different operating conditions, separately. The results show that the numerical simulation is in good agreement with the experimental data obtained from the model test. It is found that the vortex motion, separation flow and shock phenomenon are considered to be hydrodynamic factors for the formation of entropy. Furthermore, draft tube accounts for the greatest proportion of entropy production, which is ascribed to the vortex rope. Vortex rope will rotate in the same direction as the runner, but the rotational speed is lower, resulting in low frequency pressure pulsation with large amplitude in the draft tube. It is concluded that the key reason why great energy dissipation is caused in the draft tube is that the vortex rope is transporting continuously towards the downstream, especially when the turbine deviating from optimum operating point.

South China hosts more than 80% W reserves of China and about 50% of the world, with thousands of world-class W deposits of various types. Recently, more and more giant W deposits have been discovered in both the Nanling region to the south and the Yangtze River region to the north, such as the Zhuxi, Dahutang, Pangushan, and Taoxikeng deposits. In this paper, based on previous publications and new exploration results of the W deposits in South China, the majority of such deposits are reviewed, and are divided into 8 types: quartz-vein, skarn, greisen, porphyry, granite veinlet-disseminated, fractural-hydrothermal, stratabound, and weathering-placer types. Those deposits are closely related to the widely-distributed granitoids. These ore-bearing granitoids typically belong to S-type or highly-fractionated I-type metaluminous-peraluminous calc-alkaline granitic magma series. The magma fractionation degrees are generally increased from those associated with skarn-type W deposits to those with veinlet-disseminated deposits. Crust materials played a key role in the formation of these W-mineralized granites, and also contributed to the various associated metals, such as W-Cu, W-Sn, W-Bi, W-Mo, and W-Be. According to the temporal-spatial association of W deposits with tectono-thermal events in South China, three metallogenic belts can be outlined for future exploration: Nanling W metallogenic Belt (NLB) (170–150 Ma), Eastern Yangtze W metallogenic Belt (EYB) (150–120 Ma), and Southeast Coast W metallogenic Belt (SCB) (120–80 Ma). According to the deep crustal structure features of these W metallogenic belts combined with characteristics of different W mineralization types, a generic model is proposed for the formation of the Mesozoic W deposits in South China. During the Mesozoic, from the southeast coast to the inland, the South China block experienced the west-toward subduction, retreating and conversion of the paleo-Pacific plate. Furthermore, deep faults in different areas enhance the local crust-mantle interaction, and W deposits types and temporal-spatial distribution of Mesozoic W deposits in different belts have good correspondence to the deep processes.

In this paper, the hydrodynamic forces and vortex distributions of a riser subjected to a non-uniform flow generated by an upstream oscillating wing structure are simulated using high-precision code Incompact3d combined with immersed boundary method. The effects of in-line and transverse positions, oscillating frequency and amplitude on riser performance have also been discussed. It is found that with the increase of in-line spacing or the decrease of oscillation frequency and transverse positions, the time-averaged drag coefficient of riser changes from the negative values to positive values. The time-averaged lift coefficient of riser is generally insensitive to oscillation frequency. However, it shows a large shift when changing the transverse positions or the amplitude of the wing is larger than π/6. Moreover, for various in-line positions, oscillating frequency and amplitude, the vortex shedding of the rigid riser, indicated by the main frequency of lift force, is always locked by the oscillating wing. However, when the transverse position is changing, the ratio of main frequency of lift coefficient to the swing frequency does not still remain 1:1. More concretely, the maximum time-averaged drag coefficient and lift coefficient Root-mean-square value of 0.559 and 1.629 is obtained in the simulation respectively.

Fluid structure interaction (FSI) problems are often encountered in ocean science and technology. In this present, an implicit immersed boundary (IB) method combined with Lattice Boltzmann Method (LBM) and finite element method (FEM) is presented for the strong-coupled simulations of fluid structure interaction. Velocity field is solved rapidly by lattice Boltzmann-BGK equations without external force, and the deformation of a flexible structure was computed by FEM. Fluid structure coupling was processed by immersed boundary implicit forced method. The resulting combination gives an easy-to-use, inexpensive and accurate technique to solve FSI problems. Simultaneously, the body force on the immersed boundary can be calculated directly and acts as the load for structure solver, so the displacement of structure can be obtained at the same time, which is avoid the time lag between the fluid solver and solid solver. Several examples including flow over a static and deformable plate, and the flow problems of an oscillating and cantilever flexible plate were simulated and analyzed. The results agree well with the previous experimental and numerical investigations, which indicate the IB-LB-FEM proposed in this paper is an efficient and reliable fluid-structure interaction numerical simulation method.

Off-stoichiometric full-Heusler alloy Co2MnAl thin films with different thicknesses are epitaxially grown on GaAs (001) substrates by molecular-beam epitaxy. The composition of the films, close to Co1.65Mn1.35Al (CMA), is determined by x-ray photoelectron spectroscopy and energy dispersive spectroscopy. Tunable perpendicular magnetic anisotropy (PMA) from 3.41 Merg/cm3 to 1.88 Merg/cm3 with the thickness increasing from 10 nm to 30 nm is found, attributed to the relaxation of residual compressive strain. Moreover, comparing with the ultrathin CoFeB/MgO used in the conventional perpendicular magnetic tunnel junction, the CMA electrode has a higher magnetic thermal stability with more volume involved. The PMA in CMA films is sustainable up to 300°C, compatible with semiconductor techniques. This work provides a possibility for the development of perpendicular magnetized full-Heusler compounds with high thermal stability and spin polarization.

In this paper, we propose a new watermarking algorithm for chaotic sequence based on wavelet transformation from the traditional digital watermarking algorithm in wavelet domain which has been introduced. We have researched the basic steps of watermarking embedding and extraction algorithms for the chaotic sequence and we have analyzed the new algorithm by the simulation experiments. The results show that the algorithm is adaptive highly. Moreover, it not only could get a better embedding effects, but also it can adjust the depth of the embedding and can be applied to different gray-scale image widely. Introduction With the rapid development of the computer network technology, the watermarking algorithm becomes more and more outstanding, which has solved many information obstacles. It becomes a good way to ensure the integrity and reliability of digital information through the detection and analysis of the watermark. The watermarking algorithm also becomes effective means to the protection of intellectual property rights and digital multimedia security . It also has been used in multimedia information security, image processing and analysis and other fields. Almost all the previous watermarking algorithms are independent [2] .This paper presents a new watermarking algorithm for chaotic sequence based on wavelet transformation. The author studies the basic steps of watermarking embedding and extraction algorithms for the chaotic sequence and analyzes the new algorithm through the simulation experiments. The results show that the algorithm is highly adaptive and get better embedding effects. We found that it also can adjust the depth of the embedding and can be applied to different gray-scale image widely. Experiments show that this algorithm has more practical value. The wavelet transform watermark algorithm The DCT transform is used in the traditional Watermarking algorithm based on transform domain. Due to the wavelet transform is more suitable for human visual system than the DCT transform in image processing (HVS), at the present stage of watermarking algorithm based on wavelet transform has become the study focus of transform domain watermarking algorithm. And International Conference on Computational Science and Engineering (ICCSE 2015) © 2015. The authors Published by Atlantis Press 64 using DWT (Discrete Wavelet Transform) in JPEG2000 makes the watermarking algorithm based on wavelet transform is more feasible. In wavelet domain, the high frequency part represents the edge and texture image portion. Embedding watermark in here, it is not easy to be found, but such watermarking may be loss after the image had been processed. On the other hand, the low frequency part concentrates most the energy of the image, so the low frequency part has concentrated most information of the image. The power in the low frequency part is not easy to be lost, however, the low frequency part represents the image smooth areas and this part of the change is easy to affect the quality of the image. The watermarking algorithm based on wavelet transform used in this paper is as follows: firstly, we divided the image, which has been through three level wavelet transform into identical parts with the watermark image block size and without overlap. Then the same watermark had been embedded to each image block. The image area of the high frequency part is larger and it is divided into many small images, so the more of the image block number, the more of the embedded watermark. But the low frequency part accounts for small parts of the image, so the image block quantity are few, the embedded watermark is less naturally. In this way, we can realize the watermark information embedded in the high frequency part is more and the watermark information embedded in the low frequency part is less requirements. The same watermark is repeatedly embedded in different parts of the image, so it is greatly improve the robustness of watermarking. Application of chaotic sequence in the watermarking algorithm Chaotic function has the property of stretch lengthen and retrace overlap, so it is unpredictable. Chaotic sequence is a pseudo-random sequence, which is generated easily by iterative equations or nonlinear equations. In this paper, chaotic sequence generated by discrete time dynamic system Logistic mapping, which is defined as ) 1 , 0 ( ), 1 ( 1     k k k k x x x x  (1) The bifurcation parameter in 4 0    in equation (1), after transformation, the Logistic mapping in [-1, 1] can be expressed as ) 2 , 0 ( , 1 2 1       k k x x (2) With the  gradual increase, the iteration occur multiple times mutation, when  =1.40 115, the system enters a chaotic state, then 0 mean,   like self correlation and cross-correlation is 0, it become chaotic sequence, the statistical properties of the sequence is the same as white noise. This paper takes  =2, the initial value 0 x =0.3, according to formula (2) iteration, we obtain a sequence K X . The method of chaotic sequences added in digital watermarking has many kinds, the paper adopts the watermarking image W is expressed as a vector of the form p W , N M p      , , 2 , 1 .

To investigatre appropriate macroporous resins and the optimal technological parameters of the purification process of tartary buckwheat total flavonoids.Static and dynamic adsorption-desorption methods were adopted, and evaluated for separating efficiency by macroporous resins absorption rates, desorption rates.The DM -2 macroporous resin had the best separating efficiency. The best absorbed condition is H2O as solvent of extracts, diameter vs height: 1: 10, pH 3 - 4, absorption power: 3.0 mL x min(-1). The optimum adsorption condition is the volume of 50% ethanol 80 mL (approximately 5 BV (resin bed volume) as eluting solvent, pH 8, the desorption power: 3.0 mL x min(-1).This technology is simple, quick and cost-effective, which is suitable for industrialization.

This study examines the spatio-temporal variations in the sea-surface chlorophyll-a (Chl-a) concentration and their associated underlying driving forces in the northern South China Sea (SCS) from 2004 - 2010. A stratified analysis method and the Moderate Resolution Imaging Spectroradiometer (MODIS) Chl-a product, the National Centers for Environmental Prediction (NCEP) reanalysis data, with maps of monsoon winds and current systems were used in this work. Validation indicated that the MODIS-derived Chl-a is in good agreement with in-situ measurements (R2 = 0.815), accurate enough for analyzing the temporal-spatial variations of Chl-a in the northern SCS. The results show that the spatial heterogeneity of the Chl-a concentration was lowest in winter and increased in spring. The seasonal Chl-a concentration dynamics varied spatially and depended predominantly on the distance from the coastline. The most important factors that affect the Chl-a concentration spatial variability were identified as the monsoon, surface current and sea surface temperature (SST).