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[en] The deposit No.60 is located in the Shenyuan continental volcano basin of middle part of Ganhang belt with syngeneic deposit characteristics. Its U-P mineralization is controlled by certain strata. And the deposit No.60 is a hot water deposit of the continental basin, which is rebuilt by hydrotherm superimposition
[en] Long-term power system expansion planning studies are carried out to meet the electricity requirement in the future. Prior to the expansion planning studies, it is essential to know the energy potential of the existing generating system, especially the hydro power plants. Detailed hydro thermal stimulation studies of the integrated system is therefore carried out to determine the best way to maximise the hydro energy of the existing and committed plants. The results of the integrated system simulated model are stored in numerous files and are available for retrieval. Most important output used for expansion analysis is the energy production of each hydro plant. The annual hydro energy potential of the total hydro system of Sri Lanka for the hydrological year from 1949 to 1988 is given. Hydro condition data with different probability levels are also indicated
[en] An approach to the control of the sizes of oxide and metal nanoparticles produced in solutions is presented. It is assumed that a key point is the spontaneous formation of neutral hydroxo complexes usually containing 24 metal atoms. Their progressive development is either further self-assembly with the formation of particles of various-dimensions or functioning as heteroepitaxial nuclei in the formation of nanoparticles with a different composition
[ru]В работе излагается подход к управлению размерами наночастиц оксидов и металлов, образующихся в растворах. Предполагается, что ключевым моментом является спонтанное образование незаряженных аква-оксо-гидроксокомплексов, содержащих обычно 24 атома металла. Путем их прогрессивного развития является или дальнейшая самосборка с образованием частиц различной мерности, или функционирование как гетероэпитаксиальных зародышей при образовании наночастиц другого состава
[en] Distribution and Genesis of low-thermal water in Zhoujiashan deposit are fully analyzed on the basis of logging temperature data. With 'past inferred from present' method and uranium mineralization mechanism, relationship between palaeo-thermal water and uranium mineralization is discussed, a metallo-genetical prospect is hopeful predicted in the depth of Zhoujiashan deposit
[en] Uranium mineralization types at the southwestern segment of Chenzhou-Qinzhou uranium metallogenic belt is various and complicated. Because the formation time of the mineralization and granite is quite different. The mineralization formed in a narrow time gap which coincides with the faulted down period of the regional extension in Later Yanshanian. Different types of uranium deposit are low temperature hydrothermal uranium deposit which is controlled by the deep great fracture due to the spreading. There are many sources for the uranium mineralization. (author)
[en] Preparation of hydrothermal hot-pressed (HHP) compacts of the stoichiometric hydroxyapatite and solid-solution of magnesium hydroxyapatite powders (HAp and Mg-HAp) was carry out at different temperatures 150, 175 and 200°C, using uniaxial pressure load of 60MPa for 6h, with the addition of 10% wt. of deionized water as a solvent. The starting powders were obtained by hydrothermal synthesis at 150°C for 10h. The HHP compacts were chemical, physical and mechanically characterized. According to the results, it has been determined that an increase of the HHP temperature stimulate the reaction between the added water and the particles of HAp or Mg-HAp, which results on an increase of crystallinity degree without the formation of any addition products or alteration of the HAp structure. This result is particularly relevant, due to during HHP process, the production of effective packing of the particles which is activate by the dissolution-recrystallization mechanism in presence of added water which allow a densification near of 70%. For the HHP compacts of the HAp and Mg-HAp prepared at 200°C, with porosity near to 30-36% of open pores, achieve the maximum apparent density value of 3.085±0.138g/cm3 and 2.792±0.021g/cm3, respectively, with the maximum tensile strength of 7.10±0.20 and 5.89±0.06MPa. From these results, the obtained HHP compacts might be useful for orthopedics and/or dentist applications.
[es]Compactados de hidroxiapatita estequiométrica (HAp) y solución sólida de magnesio hidroxiapatita (Mg-HAp) fueron preparados mediante la técnica de compactación hidrotérmica en caliente (CHC), a diferentes temperaturas (150, 175 y 200°C), utilizando una presión de carga uniaxial de 60MPa durante 6h, con la adición del 10% en peso de agua desionizada. El material de partida fue obtenido mediante síntesis hidrotérmica a 150°C durante 10h. Los productos compactados fueron caracterizados química, física y mecánicamente. De acuerdo con el análisis de resultados, se determinó que un incremento en la temperatura de CHC favoreció la reacción entre las partículas de HAp o Mg-HAp y el agua promoviendo fases con mayor grado de cristalinidad, sin generar subproductos o alteraciones estructurales. Este resultado es particularmente relevante, ya que durante la CHC se produce un empaquetamiento efectivo de las partículas, activado por el mecanismo de disolución-recristalización en presencia del agua, con lo cual se logró una densificación del orden del 70%. Los compactados de HAp y Mg-HAp obtenidos a 200°C, con porosidad abierta del orden del 30-36%, mostraron valores de máxima densidad aparente de 3,085±0,138g/cm3 y 2,792±0,021g/cm3, respectivamente, con una máxima resistencia a la tensión de 7,10±0,20 y 5,89±0,06MPa. De acuerdo a estos resultados, el material obtenido podría ser utilizado en aplicaciones ortopédicas y/u odontológicas.
[en] Complete text of publication follows. A dense magnetotelluric measurement with 85 sites was carried out at Kusastu Shirane volcano, Japan. The main goal of this study is to delineate the hydrothermal system derived from the three dimensional electromagnetic image. We applied the 3D inversion code of Shiripunvarapon et.al. (2005) to calculate 3D electrical conductivity structure. To overcome the effect of shallow three dimensional structure or galvanic distortion, We have also developed the methodology of modeling by applying phase tensor and induction vector as response functions calculated from the 3d forward modeling. The three-dimensional topography was also taken into account in the 3d forward modeling and two-dimensional inversion results of multiple profiles were used as the initial three-dimensional model. By comparison the results from this different scheme, the final resistivity model shows that there is not significant difference especially in some general features. The main structure of the conductive zone was found in the center of the model to a depth of 500 m from the surface. This conductor ranging of 1- 5 ?.m was distributed in the area of measurement. The existence of this conductor is clearly detected by the induction vectors at frequencies 100Hz and 10 Hz, which point toward the center of the model. Based on the drilling data, the clay was found at the depth of 500 m which is the bottom of conductive zone in this model. Below this circular-shape conductive, there is a significantly resistive zone around the crater surrounded by conductive zone. This resistive conduit-like is important features because it is located just beneath circular-shaped clay cap and low earthquakes are sparsely distributed throughout this resistive conduit-like. The loss of high conductivity in this zone implies that the conductive clay cannot exist as the temperature is significantly higher than 200 deg C. Moreover, the existence of the seismicity in the resistive conduit-like indicated that the trapped free water in the transition zone is the cause of the earthquake generation.
[en] This paper proposes a chaotic hybrid differential evolution algorithm to solve short-term hydrothermal system generation scheduling problem. In the proposed method, chaos theory is applied to obtain self-adaptive parameter settings in differential evolution (DE). In order to handle constraints effectively, feasibility-based selection comparison techniques and heuristic rules embedded into DE are devised to guide the process toward the feasible region of the search space. A test hydrothermal system is used to verify the feasibility and effectiveness of the proposed method. Results from the proposed method are compared with those obtained by augmented Lagrange and two-phase neural network methods in terms of solution quality. It is shown that the proposed method is able to obtain higher quality solutions
[en] This paper proposes a new method for the solution of the short term hydrothermal scheduling problem. The overall problem is decomposed into hydro and thermal sub-problems which are solved independently. The hydro sub-problem is solved by the proposed enhanced peak shaving method, which allows the incorporation of the coupling hydraulic constraints. The peak shaved load curve is supplied by the thermal generating units. The thermal sub-problem is solved by an efficient simulated annealing algorithm. Numerical simulations on a realistic power system have proven the efficiency of the proposed method
[en] Mudstones in the Sha-3 member of the Shahejie Formation, in the Tanggu area of the Huanghua Depression, have been found to contain analcime and ankerite. Hydrothermal sedimentation has been invoked to explain the origin of these two minerals, raising the question of whether hydrothermal activity occurred at a sufficient scale to significantly raise the salinity of the depositional environment. We applied a suite of organic petrological and geochemical methods to directly address this question. Maceral composition, kerogen type, and the distribution of n-alkanes, hopanes, and steranes indicate that the organic matter contained in these mudstones and dolomitic mudstones is mainly derived from algae and bacteria. The dominant acritarch genera, C31R/C30 hopane ratio, gammacerane index, Pr/Ph ratio, and the relationship between Pr/n-C17 and Ph/n-C18 suggest that the mudstones and dolomitic mudstones were deposited in an anoxic, saline lacustrine environment. Tmax, biomarker maturity indices, the Thermal Alteration Index (TAI) and Acritarch Alteration Index (AAI), and vitrinite reflectance all indicate that the organic matter is at an immature to early mature stage. The estimated maximum paleotemperature is close to the present-day burial temperature, and much lower than the homogenization temperature of the analcime veins in dolostones. Combined with the absence of unresolved complex mixtures on the n-alkane pattern, this suggests that hydrothermal activity had a negligible impact on the salinity and alkalinity of the depositional lake.