Chemical, and Sr and Li isotopic composition of pore fluids and sediments from ODP Leg 170 and Leg 205 sites

Pore fluid and sediment chemical and isotopic data were obtained for samples from Ocean Drilling Program (ODP) Leg 205 Sites 1253, 1254, and 1255 in the Costa Rica subduction zone. The chemical and isotopic data reported here were generated in our shore-based laboratories to complement shipboard inorganic geochemical data. Li isotopic analyses were carried out by L.-H. Chan at Louisiana State University (USA). The data reported herein include fluoride, bromide, rubidium, cesium, and barium concentrations; Li and Sr isotopic compositions in pore fluids; and Rb, Cs, and Ba concentrations in representative bulk sediments. The data also include new pore fluid fluoride and bromide concentrations from corresponding ODP Leg 170 Sites 1039, 1040, and 1043. O.M. Saether's Site 1039 and 1040 fluoride concentration data are shown for comparison. Basal sediment fluoride concentrations and Li and Sr isotope ratios at both Sites 1253 and 1039 show reversals that approach modern seawater values. Br/Cl ratios are, however, conservative throughout the sediment section at Sites 1039 and 1253. The observed sharp F and Br concentration maxima, Rb and K concentration minima, the most radiogenic 87Sr/86Sr ratios, and highest 7Li values along the décollement and fracture zone (Sites 1040, 1043, 1254, and 1255) strengthen the evidence obtained during Leg 170 that a deeply sourced fluid, originating from fluid-rock reactions at ~150°C and corresponding to between 10 and 15 km depth, is transporting solutes to the ocean.

Carbon and Nitrogen concentrations and isotopic composition of ODP Site 170-1040 and Leg 205 sites

We determined the C and N concentrations and isotopic compositions of sediments in the prism sampled during Ocean Drilling Program Legs 170 and 205 offshore Costa Rica, with the goals of evaluating sediment sources and extents of diagenesis and identifying any effects of infiltrating fluids on the sedimentary C and N. The sediments from Leg 170 Site 1040 contain 0.85-1.96 wt% total organic carbon (TOC) with Vienna Peedee belemnite (VPDB) d13CVPDB from -26.3 per mil to -22.5 per mil, and 832-2221 ppm total nitrogen (TN) with d15Nair from +3.5 per mil to +6.6 per mil. Sediment TN concentrations and d15N values show dramatic downhole increases within the uppermost 130 m of the section and more gradual downhole decreases from 130 meters below seafloor (mbsf) to the base of the décollement at ~370 mbsf. Concentrations and isotopic compositions of TOC are relatively uniform within the entire section, showing some minor perturbation within the décollement zone. In the uppermost 100 m, upsection increases in TN concentrations at constant TOC concentrations produce significant increases in atomic TOC/TN ratios from ~8 to ~18. Carbonate (calcite) contents in the wedge sediments are generally low (<4 wt%), but the d13C and Vienna standard mean ocean water (VSMOW) d18OVSMOW values vary significantly from -26.1 per mil to +4.1 per mil and from +30.0 per mil to +35.3 per mil, respectively. Concentrations and isotopic compositions of TOC and TN for sediments from Leg 205 Sites 1254 and 1255 overlap well with C-N data for sediments from the same depth intervals obtained during Leg 170 at Site 1040.

Consolidation properties and permeability values of sediments from three ODP Leg 205 sites

Vertical permeability and sediment consolidation measurements were taken on seven whole-round drill cores from Sites 1253 (three samples), 1254 (one sample), and 1255 (three samples) drilled during Ocean Drilling Program Leg 205 in the Middle America Trench off of Costa Rica's Pacific Coast. Consolidation behavior including slopes of elastic rebound and virgin compression curves (Cc) was measured by constant rate of strain tests. Permeabilities were determined from flow-through experiments during stepped-load tests and by using coefficient of consolidation (Cv) values continuously while loading. Consolidation curves and the Casagrande method were used to determine maximum preconsolidation stress. Elastic slopes of consolidation curves ranged from 0.097 to 0.158 in pelagic sediments and 0.0075 to 0.018 in hemipelagic sediments. Cc values ranged from 1.225 to 1.427 for pelagic carbonates and 0.504 to 0.826 for hemipelagic clay-rich sediments. In samples consolidated to an axial stress of ~20 MPa, permeabilities determined by flow-through experiments ranged from a low value of 7.66 x 10**-20 m**2 in hemipelagic sediments to a maximum value of 1.03 x 10**-16 m**2 in pelagic sediments. Permeabilities calculated from Cv values in the hemipelagic sediments ranged from 4.81 x 10**-16 to 7.66 x 10**-20 m**2 for porosities 49.9%-26.1%.

Permeabilities, grain size and carbon composition of sediments from ODP Hole 170-1040C and two Leg 205 holes

Constant-pressure difference and constant-flow permeability tests were conducted on core samples from Ocean Drilling Program Legs 170 and 205 from the Costa Rica subduction zone representing pelagic carbonate and hemipelagic mud lithologies. Seven whole-round core samples from Sites 1040, 1253, and 1255 were tested for vertical permeabilities. The permeabilities of the pelagic carbonate sediments range from ~4 x 10**-16 to ~1 x 10**-15 m**2. The permeabilities of the hemipelagic mud sediments vary from ~2 x 10**-18 to ~4 x 10**-18 m**2. To further characterize the sediments, grain size, total carbon, and total inorganic carbon analyses were conducted.

Phospholipid fatty acid and quinone composition of sediments from ODP Leg 205 sites

Assessing the habitability of deep-sea sediments undergoing compaction, compression, and subduction at convergent margins adds to our understanding of the limits of the terrestrial biosphere. In this work, we report exploratory biomarker data on sediments obtained at Ocean Drilling Program (ODP) Sites 1253, 1254, and 1255 during drilling at the Costa Rica subduction trench and forearc sedimentary wedge. The samples selected for postcruise biomarker analyses were located within intervals of potentially enhanced fluid flow within the décollement and sedimentary wedge fault zones (Sites 1254 and 1255) and within basal carbonates at the reference site (Site 1253). The passage of fluids that are geochemically distinct from ambient interstitial water provides a disequilibrium setting that may enhance habitability. Biomarker data show low levels of microbial biomass in subseafloor sediments sampled at the Costa Rica convergent margin as deep as ~370 meters below seafloor.

205-14 A Monograph of the plant-infecting members of the Order Clavicipitales in

Taxonomic revision of ergots and related fungi in Australia.

Sapientia, 1999, Vol. LIV, nº 205 (número completo)

Contenido: La encíclica Fides et ratio de Juan Pablo II / La Dirección – Die Gegenwart del Themis bei Parmenides un der entzug der bestimmung im Heideggers Lichtung / Stefan Winter – El tiempo como medida de la primera esfera en la Física de Aristóteles / Marcelo L. Imperiale – St. Albert the Great and St. Thomas Aquinas on the presence of elements in compounds / Steven Baldner – Santo Tomás de Aquino, psicólogo / Ignacio Andereggen – Aquinas on creation and the metaphysical foundation of science / William E. Carroll – Las fuentes jurídicas romanas en Santo Tomás de Aquino / Alfredo Gustavo Di Pietro – La causalidad humana en la filosofía de la historia de Giambattista Vico / Juan Francisco Franck – Questions disputées de la politique chrétienne de Jacques Maritain / Yves Floucat – Die tektonik des submodernen Denkens im Schein ihrer Kunst / Heribert Boeder – El concepto de tolerancia / Alejandro G. Vigo – Modern science and time: an evaluation / Leo J. Elders – Tecnociencia y crisis ambiental / Héctor J. Padrón – The importante of order in theological discusión / Timothy L. Smith – La metafísica a pesar de Heidegger / Mario Enrique Sacchi – Notas y comentarios – Bibliografía

Diário da Constituinte [gravação de vídeo] : [programa n. 205]

Grupo dos 32 (Trinta e dois) reúne-se para estudar os pontos críticos do substitutivo apresentado pelo Relator Bernardo Cabral, em busca de entendimento com o Grupo do Consenso em relação a temas como a reforma agrária, a anistia e sistema tributário. O Grupo dos 32 examinou também o capítulo sobre a administração pública. A Deputada Sandra Cavalcante (PFL-RJ) informa que a administração pública necessita de regras mais rígidas, de forma a acabar com o clientelismo dentro do Estado. Para o PMDB o substitutivo do relator, Deputado Bernardo Cabral (PMDB-AM), tem avanços importantes, mas há pontos que precisam refletir melhor as posições defendidas pelo partido. O Líder do PMDB, Deputado Mário Covas, considera que, tanto quanto possível, a Constituição será objeto de negociação, mas há certos temas que terão que ser decididos pelo voto no Plenário da Assembleia Nacional Constituinte (ANC). Um dos pontos que o PMDB quer mudar é a Reforma Agrária. Para José Eduardo Raduan, Presidente do Instituto Nacional de Colonização e Reforma Agrária (INCRA), é inviável a Reforma Agrária com imissão de posse após 90 dias da desapropriação. Projeto de Constituição não torna obrigatório o diploma de jornalismo para ser jornalista. O Deputado Carlos Alberto Oliveira (PDT-RJ) considera que é desastroso para o exercício de cidadania, porque a profissão de jornalista é tão especializada como tantas outras. A Deputada Cristina Tavares (PMDB-PE) declara que se trata de um dos mais graves retrocessos. Estudantes e professores de comunicação também são contra o fim da exigência de diploma. O professor de comunicação da UNB Wladimir de Carvalho declara que o caso parece ser resultado de um lobby da grande imprensa. Já o também professor de comunicação da UNB Murilo Ramos informa que o objetivo é abrir o mercado de mão-de-obra, para aumentar o lucro dos empresários. O Deputado Antônio Brito (PMDB-RS) afirma que a luta não é só dos jornalistas e sua situação profissional, mas que há preocupação com o país e com a qualidade da informação que os brasileiros receberão.

二(2,4,4-三甲基戊基)单硫代膦酸-上胺205-正庚烷乳状液膜萃取分离钪(Ⅲ)、铁(Ⅲ)和镥(Ⅲ)

本文研究了外水相ｐＨ值、流动载体浓度、表面活性剂浓度、内相解析酸浓度、水乳比、油内比等因素对二（２，４，４－三甲基戊基）单硫代膦酸（Ｃｙａｎｅｘ３０２）－上胺２０５－正庚烷乳状液 膜迁移Ｓｃ（Ⅲ）的影响。在一定条件下，Ｓｃ（Ⅲ）可以快速而完全地迁移，有可能实现Ｓｃ（Ⅲ）与Ｆｅ（Ⅲ）、Ｌｕ（Ⅲ）的分离。

异丙基膦酸单(1-己基-4-乙基)辛酯上胺205-正庚烷乳状液膜分离钪(Ⅲ)、铁(Ⅲ)、镥(Ⅲ)

本文研究了异丙基膦酸单（１－己基－４－乙基）辛酯（简称ＰＴ－２）上胺２０５－正庚烷乳状液膜分离钪（Ⅲ），铁（Ⅲ），镥（Ⅲ）及外相酸度、表面活性剂浓度、流动载体浓度和内相酸度对Ｓｃ（Ⅲ）、Ｆｅ（Ⅲ）、Ｌｕ（Ⅲ）迁移影响。实验结果表明，在一定的条件下Ｓｃ（Ⅲ）有可能实现与Ｆｅ（Ⅲ）、Ｌｕ（Ⅲ）的分离。

二(2,4,4-三甲基戊基)膦酸-上胺205-正庚烷乳状液膜分离钪(Ⅲ)、铁(Ⅲ)和镥(Ⅲ)

本文研究了二（2，4，4-三甲基戊基）膦酸（Cyanex272）-上胺205-正庚烷乳状液膜分离Sc（Ⅲ）、Fe（Ⅲ）和Lu（Ⅲ）。考察了外相酸度、表面活性剂浓度、流动载体浓度及内相盐酸浓度对Sc（Ⅲ）迁移的影响。并探讨了该液膜体系分离Sc（Ⅲ）、Fe（Ⅲ）和Lu（Ⅲ）的可能性，结果表明，该体系对于稀土矿中Sc（Ⅲ）的分离与分析有良好的应用前景。