985 resultados para 333.5


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我国江西龙南稀土矿是目前世界上储量最大的富钇稀土矿、研制具有多种用途的钇(Y)-铝(Al)或富钇混合稀土(Ymm)-铝中间合金,对于开拓我国龙南稀土矿的应用领域扩大稀土合金出口具有重要意义。基于这一背景并针对目前氟化物体系制取Ymm-Al合金时存在着电解温度高,腐蚀现象严重,电效偏低等缺点,本文系统开展了在氯化物熔盐体系中电解制取Ymm-Al合金的研究工作。本工作由三部分组成:在第一部分工作中,开展了熔盐电解所需要基本原料-无水稀土氯化物制取的工艺研究。利用化学分析和结构分析手段,弄清了干法氯化过程中YmmCl_3水解的机理,提出了减弱水解的措施,即YmmCl_3先在850-900 ℃灼烧1.5 + 0.2hr,脱掉吸附水并将碱式碳酸盐转化为氧化物,增加稀土氧化物的比表面。通过条件试验得到最佳工艺条件为:采用NH_4 Cl:Ymm_2 O_3 = 14:1(摩尔比)的配料比,每次投入氯化装置的原料量为0.26 - 0.36 kg, 在400-450 ℃氯化反应激烈开始后迅速降温至400 ℃以下,待物料粘结现象消失后,再行升温氯化。出料及后期控制温在475 ± 25 ℃。经过3.8 ± 0.2hr氯化,可制得水不溶物小于1%并符合熔盐电解要求的YmmCl_3原料。此新工艺与原有干法工艺相比,流程短,装置简单,不需密闭抽真空,成本低,适于制取任何量的优质熔盐电解所需氯化稀土原料。在第二部分工作中,利用上述YmmCl_3原料,以液态铝为阴极,在氯化物体系中进行熔盐电解,通过试验得出在小型试验规模制取Ymm-Al合金的最隹工艺条件为:电解质组成(重量比)40%YmmCl_3-1%NaF-59%等摩尔的NaCl-KCl;电解温度为790 ± 5 ℃;阴极电流密为0.7 - 0.02A/cm~2;电解电量为333 ± 5库仑/克铝,制得钇铝合金中Ymm含量为10 ± 2%。添加1%的NaF可消除阴极表面生成枝状物,减少合金中夹渣和熔盐中沉渣。在电解工作中,将方差分析应用于试验数据处理,方差分析结果表明,各种试验因素对电效有明显影响,试验数据可靠,试验误差在允许范围以内。在第三部分工作中,利用线性扫描伏安法测定了在最隹电解工艺条件下Y~(3+)和Ymm在液态铝及钼电极上的析出电位。测定结果表明:Y~(3+)和Ymm~(3+)在液态铝阴极上的析出电位比在钼阴极上偏正0.2 ~ 0.8伏,氟离子的加入要比不加氟时析出电位不有同程度的负移,但考虑到氟离了具有消渣作用,加入少量氟比物添加剂对提高电效有利。

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In this paper, we determined the concentrations of antimony species (antimonite (Sb(III)), antimonate (Sb(V)) and dissolved inorganic antimony (DISb)) and arsenic, in Bohai Bay seawaters, as well as the relationships of the analytes with environmental factors such as seawater characteristics (e.g., suspended particulate material (SPM), salinity and total organic carbon (TOC)), heavy metals, nutrients and phytoplankton species, and evaluated the sources of arsenic and antimony. Dissolved arsenic and antimony concentrations in the surface waters were ranging spatially from 1.03 to 1.26 ng/ml and 0.386 to 1.075 ng/ml, with mean values of 1.18 and 0.562 ng/ml, respectively. Sb(V) as the prominent chemical species constituted about 89%. Regarding arsenic concentrations in the surface waters, there was a tendency for a small variation. However, antimony species concentrations were much variable than arsenic. The highest arsenic and antimony concentrations were found near the Haihe Estuary. These distribution patterns were controlled mainly by environmental factors, biological activities and sources. In this region, DISb and Sb(V) negatively correlated with salinity. Besides, arsenic and antimony correlated well with the nutrients, chlorophyll a and phytoplankton, implying that arsenic and antimony had been involved in biological cycling. In addition, according to our estimate, about 333.5 x 10(8) mg/year of arsenic and 454.2 x 10(8) mg/year of antimony reached Bohai Bay via rivers. (C) 2010 Elsevier Ltd. All rights reserved.

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Acute alterations in cell volume can substantively modulate subsequent metabolism of substrates. However, how such alterations in skeletal muscle modulate protein metabolism is limited. The purpose of this study was to determine the time dependent influence of extracellular osmotic stress on protein turnover in skeletal muscle cells. L6 cells were incubated in hyperosmotic (HYPER; 425.3 ± 1.8mmol/kg), hypo-osmotic (HYPO; 235.4 ± 1.0mmol/kg) or control (CON; 333.5 ± 1.4mmol/kg) media for 4, 8, 12, or 24hrs. During the final 4hrs, incorporation of L-[ring-3,5-3H]-tyrosine was measured to estimate protein synthesis. Western blotting measured markers of protein synthesis and degradation. No differences were observed in any outcomes except p70S6K phosphorylation whereby HYPO was lower (p<0.05) than CON and HYPER; which remained similar except for a large increase at 8hrs for HYPER. These findings suggest that regardless of duration, extracellular osmotic stress does not significantly affect protein metabolism in L6 cells.

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Objetivo: Describir los elementos diagnósticos de la patología de hombro doloroso, en trabajadores calificados en medicina laboral EPS-privada, Bogotá (Colombia), año 2012. Método: Estudio descriptivo de corte transversal sobre una muestra de trabajadores afiliados a EPS-privada año 2012 calificados por patología de hombro doloroso de origen profesional. La muestra estudiada fue de 343 registros de trabajadores, que representa el 2.3% del total de la enfermedades profesionales y accidentes de trabajo de todas las patologías calificadas. Resultados: Los diagnósticos de hombro doloroso encontrados son: Bursitis 91.54%, Manguito Rotador 6.13% y otros 2.33%. En el 100% de los casos de manguito rotador secundarios a accidentes de trabajo solo se les practicó rayos X. Para los casos de enfermedad laboral, bursitis y otros, los laboratorios practicados en el 100% de los casos fueron factor reumatoide, velocidad de eritro-sedimentación y proteína C reactiva. Las interconsultas médicas por fisiatría fueron el 100% y ortopedia el 81%; en el 30% fue necesario la realización de resonancia nuclear magnética y tomografía axial computarizada en el 44%. Se les realizó análisis de puesto de trabajo empleando el método ANSI al 61% y RULA al 32%. Conclusión: Con los elementos diagnósticos empleados en la calificación de las patologías de hombro doloroso en medicina laboral EPS-privada, Bogotá (Colombia), año 2012, solo se logra diagnosticar la Bursitis y el Manguito Rotador. Dentro de otros diagnósticos se encuentra una gran oportunidad para afinar los elementos que permitan establecer con certeza la entidad nosológica.

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A study was carried out to determine the influence of fibrolytic enzymes derived from mesophilic or thermophilic fungal sources, added at ensiling, on time-course fermentation characteristics and in vitro rumen degradation of maize silage. The mesophilic enzyme was a commercial product derived from Trichodenna reesei (L), whereas the thermophilic enzyme was a crude extract produced from Thermoascus aurantiacus (Ta) in this laboratory. The fungus was cultured using maize cobs as a carbon source. The resulting fermentation extract was deionised to remove sugars and characterised for its protein concentration, main and side enzymic activities, optimal pH, protein molecular mass and isoelectric point. In an additional study, both enzymes were added to maize forage (333.5 g DM/kg, 70.0, 469.8, 227.1 and 307.5 g/kg DM of CP, NDF, ADF and starch, respectively) at two levels each, normalized according to xylanase activity, and ensiled in 0.5 kg capacity laboratory minisilos. Duplicate silos were opened at 2, 4, 8, 15, and 60 days after ensiling, and analysed for chemical characteristics. Silages from 60 days were bulked and in vitro gas production (GP) and organic matter degradability (OMD) profiles evaluated using the Reading Pressure Technique (RPT), in a completely randomised design. The crude enzyme extract contained mainly xylanase and endoglucanase activities, with very low levels of exoglucanase, which probably limited hydrolysis of filter paper. The extract contained three major protein bands of between 29 and 55 kDa, with mainly acidic isoelectric points. Ensiling maize with enzymes lowered (P < 0.05) the final silage pH, with this effect being observed throughout the ensiling process. All enzyme treatments reduced (P < 0.05) ADF contents. Treatments including Ta produced more gas (P < 0.05) than the controls after 24 h incubation in vitro, whereas end point gas production at 96 h was not affected. Addition of Ta increased (P < 0.01) OMD after 12 h (410 and 416 g/kg versus 373 g/kg), whereas both L and Ta increased (P < 0.05) OMD after 24 h. Addition of enzymes from mesophilic or thermophilic sources to maize forage at ensiling increased the rate of acidification of the silages and improved in vitro degradation kinetics, suggesting an improvement in the nutritive quality. (C) 2003 Elsevier B.V All rights reserved.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The Central gold belt of peninsular Malaysia comprises a number of gold deposits located in the east of the N-S striking Bentong-Raub Suture Zone. The Tersang gold deposit is one of the gold deposits in the gold belt and hosted in sandstone, rhyolite and breccia units. The deposit has an inferred resource of 528,000 ounces of gold. The geochronology of the Tersang deposit has been newly constrained by LA ICP-MS U-Pb zircon dating. The maximum depositional age of the host sedimentary rocks ranges from Early Carboniferous to Early Permian (261.5 ± 4.9 Ma to 333.5 ± 2.5 Ma) for the host sandstone and Late Triassic for the rhyolite intrusion (218.8 ± 1.7 Ma). Textural characteristics of pyrite have revealed five types including (1) Euhedral to subhedral pyrite with internal fracturing and porous cores located in the sandstone layers (pyrite 1); (2) Anhedral pyrite overgrowths on pyrite 1 and disseminated in stage 1 vein (pyrite 2); (3) Fracture-filled or vein pyrite located in stages 1 and 2 vein (pyrite 3); (4) Euhedral pyrite with internal fractures also located in stage 2 vein (pyrite 4); and (5) Subhedral clean pyrite located in the rhyolite intrusion (pyrite 5). Based on pyrite mapping and spot analyses, two main stages of gold enrichment are documented from the Tersang gold deposit. Gold in sandstone-hosted pyrite 1 (mean 4.3 ppm) shows best correlation with Bi and Pb (as evidenced on pyrite maps). In addition, gold in pyrite 3 (mean 8 ppm) located in stage 2 vein shows a good correlation with As, Ag, Sb, Cu, Tl, and Pb. In terms of gold exploration, we suggest that elements such as As, Ag, Sb, Cu, Tl, Bi, and Pb associated with Au may serve as vectoring tools in gold exploration. Our new geological, structural, geochemical and isotopic data together with mineral paragenesis, pyrite chemistry and ore fluid characteristics indicate that the Tersang gold deposit is comparable to a sediment-hosted gold deposit. Our new genetic model suggests deposition of the Permo-Carboniferous sediments followed by intrusion of rhyolitic magma in the Late Triassic. At a later stage, gold mineralisation overprinted the rhyolite intrusion and the sandstone.

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中国の「西部大開発」戦略は、東部沿海地域(以下、東部)と西部内陸地域(以下、西部)の格差を是正し、内陸経済の自律的発展条件を整備することを目指した国家的プロジェクトである。同戦略に関しては、当初から肯定否定こもごもの評価がつきまとってきたが、曲がりなりにも第十次五カ年計画(2001~05年)に盛り込まれたこと、提起以来4年の間に様々な政策措置が実施され、大規模なインフラ建設が着手されたことなど、その客観的評価を試みる材料が揃ってきたと考えられる。 本稿では、まず同戦略が登場した背景と、現在までに打ち出された具体的施策を整理したうえで、西部大開発の直面する課題を検証し、今後の展望を試みる。結論部分では、日本の協力策についても考察してみたい。

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Japanese ODA, especially that undertaken by JICA, has targeted South Sulawesi Province as a core area of development in eastern Indonesia, with hope that the economic growth of South Sulawesi will bring about spillover effects in other regions. This paper tests the validity of the strategy using a framework of Vector Autoregressive model. The results show that South Sulawesi’s economy Granger causes other regions in eastern Indonesia, but not vice versa, implying that South Sulawesi drives the development of other regions in eastern Indonesia. Further analysis shows that the development of the agricultural sector in South Sulawesi potentially has the highest spillover effects than other sectors and that the magnitude of spillover effect from South Sulawesi on eastern Indonesia is higher than other economically important regions, such as Eastern Java and Kalimantan.