1000 resultados para 80-549


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Endohedral metallofullerenes Ce@C-82, Ce-2@C-80, Nd@C-82 and Nd-2@C-80 undergo gas phase ion/molecule reactions with the ion system from self-chemical ionization of vinyl acetate, and exohedral derivatives are thus generated, A new heterocycle is formed from metallofullerenes and a C2H3O+ cation, Endohedral metallofullerenes show much higher reactivities than empty fullerenes during the association and the charge and proton transfer processes, The strong electron-donating character of endohedral metallofullerenes is due to their unique super-atom-like electronic structures. (C) 1997 by John Wiley & Sons, Ltd.

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本文提出了一个借钛-4,5-二溴苯基荧光酮(DBPF)-Tween-80与蛋白质显色反应光度测定微量尿蛋白的高灵敏方法。在pH2.9,血清蛋白能与Ti-DBPF-Tween-80形成蓝色络合物,最大吸收波长为605nm。加入小量乙醇能提高方法的灵敏度和稳定性,牛血清蛋白含量在0~150μg/25ml范围内服从Beer定律。尿液中其它成分不干扰测定。用拟定的方法测定人尿蛋白,获得满意结果。

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The dye C.I. Acid Blue 80 (AB80) was easily degraded by TiO2-P25 assisted photocatalysis in aqueous dispersion under irradiation of sunlight. The optimal reaction conditions were [TiO2] = 2.0 g/L, pH = 10, [H2O2] = 5 mmol/L. The photocatalytic reaction followed pseudo-first order kinetics. The adsorption of AB80 onto TiO2 was in accord with Langmuir equation.

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雪鸡坪斑岩铜矿位于西南三江构造火成岩带义敦岛孤带,其成矿斑岩为印支期石英闪长玢岩和石英二长宽岩。研究对该矿区安山岩、矿化斑岩和矿石矿物系统进行S,Pb同位素分析结果表明:金属硫化物的δ34S值为-3.1‰~+0.7‰,平均值为-1.1‰,与矿化斑岩的硫同位素组成(-1.4‰和-1.5‰)一致,均落入幔源硫范围,表明硫主要来自岩浆;δ34S黄铁矿(-1.8‰~+0.7‰,平均0.5‰)〉δ34S黄铜矿(-2.2‰~0.0‰,平均-1.2‰)〉δ34S方铅矿(-3.1‰~1.3‰,平均-2.4‰),硫同位素分馏基本达到平衡。矿石矿物(208Pb/204Pb=37.917~38.230,平均值38.075;207Pb/204Pb-15.528~15.614,平均值15.571;206Pb/204Pb=17.929~18.082,平均值17.981)与矿化斑岩(208Pb/204Pb=37.832、37.883,207Pb/204Pb=15.529、15.538,206Pb/204Pb=17.906、17.910)以及安山岩(208Pb/204Pb=37.816~37.884,207Pb/204Pb-15.549~15.562,206Pb/204Pb=17.845~17.919)的初始铅组成基本一致,变化范围较小,表明三者具有相同的来源;在铅构造模式图上,所有样品铅同位素均位于造山带演化线上或附近,在铅同位素源区判别图中,均落入造山带和下地壳区域,这表明Pb主要来源于壳幔混合。雪鸡坪铜矿S,Pb同位素组成共同指示成矿物质主要来自于深部岩浆,这种岩浆可能主要起源于俯冲洋壳板片的部分熔融并受到少量地壳物质的混染。

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Centenarians provided autobiographical memories to either a request for a life narrative or a request to produce autobiographical memories to cue words. Both methods produced distributions with childhood-amnesia, reminiscence-bump, and recency components. The life-narrative method produced relatively more bump memories at the expense of recent memories. The life-narrative distributions were similar to those obtained from 80-year-old adults without clinical symptoms and from 80-year-old Alzheimer's dementia and depression patients, except that the centenarians had an additional 20-year period of relatively low recall between the bump and recency components. The centenarians produced more emotionally neutral memories than the other three groups and produced fewer and less detailed memories than the non-clinical 80-year-old sample.

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Going Global: planning the next 80 years of the Continuous Plankton Recorder Survey. Operated by the Sir Alister Hardy Foundation for Ocean Science (SAHFOS), the Continuous Plankton Recorder (CPR) survey is the world’s largest, sampling 4 ocean basins, and longest running (since 1931) plankton biodiversity monitoring programme. Having sampled enough miles to circumnavigate the globe over 200 times, the CPR database houses over 2.5 million entries, describing the distribution of 500 phytoplankton and zooplankton taxa. Routinely sampling in the Arctic, Atlantic, Pacific and Southern Oceans, the survey analyses 4000 samples yearly. Data collected from these samples are made freely available for bona fide scientific purposes. The CPR survey data is used to generate a better understanding of changes in the plankton and to date some 1000 papers have been published on plankton biodiversity. This year sees the 80th anniversary of the CPR survey and to celebrate and build upon this unique monitoring programme, SAHFOS intends to further develop its global plankton perspective. Work will be extended into the South Atlantic and Indian Ocean and an international partnership with complementary surveys in Australia, Canada, America, Japan and South Africa will be implemented. The Digital Object will describe the CPR survey using compilations made by Plymouth Art College and BBC film footage.

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We present intermediate-resolution HST/STIS spectra of a high- velocity interstellar cloud ((LSR)-L-upsilon = + 80 kms(-1)) towards DI1388, a young star in the Magellanic Bridge located between the Small and Large Magellanic Clouds. The STIS data have a signal-to-noise ratio (S/N) of 20-45 and a spectral resolution of about 6.5 km s(-1) (FWHM), The high-velocity cloud absorption is observed in the lines of C II, O I, Si II, Si III, Si IV and S III. Limits can be placed on the amount of S II and Fe II absorption that is present. An analysis of the relative abundances derived from the observed species, particularly C II and O I, suggests that this high-velocity gas is warm (T-k similar to 10(3)-10(4) K) and predominantly ionized, This hypothesis is supported by the presence of absorption produced by highly ionized species, such as Si IV, This sightline also intercepts two other high-velocity clouds that produce weak absorption features at (LSR)-L-upsilon = + 113 and + 130kms(-1) in the STIS spectra.

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El ordenamiento jurídico portugués consagra un régimen fiscal especial para el sector cooperativo, basado, al igual que otros ordenamientos como el español o el italiano, en la protección de la mutualidad como forma de organización empresarial especialmente benéfica en el plano social. Para alcanzar ese objetivo, el régimen fiscal cooperativo debe ser selectivo, lo que significa que al legislador se le plantea el reto de establecer criterios para separar, dentro del marco cooperativo, lo que debe ser protegido de lo que no merece protección fiscal. El legislador portugués optó por un modelo basado en dos grupos de ramos cooperativos claramente diferenciados según los beneficios fiscales aplicables, ambos con amplias exenciones fiscales. El presente trabajo no se centra en el contenido de los beneficios aplicables sino en las condiciones que las cooperativas deben reunir para acogerse a esos regímenes fiscales favorables. Estos criterios son: i) una división entre operaciones con socios y operaciones con terceros; ii) una delimitación de las operaciones o actividades cooperativas según estén o no vinculadas con el “fin propio de la cooperativa”; y iii) una estructura prevalentemente mutualista del factor trabajo. Esta fórmula legal tiene su raíz en una legislación de 1929 y se ha mantenido hasta el día de hoy debido en parte a un fenómeno de inercia legislativa. El presente trabajo, basándose en la metodología de la sociología jurídica, asienta en una encuesta dirigida a 64 cooperativas, por la que se buscaba indagar hasta qué punto estos criterios (de acuerdo con los que se seleccionan las cooperativas que pueden acogerse a los regímenes fiscales favorables) cuadran con la realidad cooperativa actual. Como era de esperar, la vetustez del régimen hizo que se encontraran desajustes muy significativos, que reclaman una reforma urgente.

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The search for funding is an ongoing task of the company, which is exacerbated, particularly in times of economic crisis, affecting also to the cooperatives. Cooperative legislation available to these entities various instruments of external financing through the issuance of securities (bonds, equity securities, special shares), to them accounts are added in participation, but without much detail in the legal texts. At work we investigate their potential, by looking, especially in those last; We seek to clarify their legal status and contrast their potential as a technical instrument, alternative for funding in the area of cooperative societies. Finally, we also see the impact of the recent Law 5/2015, of promoting business financing in the cooperative sector and ended up proposing some policy adjustments.

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Dipicolinic acid (DPA) is an excellent marker compound for bacterial spores, including those of Bacillus anthracis ( anthrax). Surface-enhanced Raman spectroscopy (SERS) potentially has the sensitivity and discrimination needed for trace DPA analysis, but mixing DPA solutions with citrate-reduced silver colloid only yielded measurable SERS spectra at much higher (> 80 ppm) concentrations than would be desirable for anthrax detection. Aggregation of the colloid with halide salts eliminated even these small DPA bands but aggregation with Na2SO4(aq) resulted in a remarkable increase in the DPA signals. With sulfate aggregation even 1 ppm solutions gave detectable signals with 10 s accumulation times, which is in the sensitivity range required. Addition of CNS- as an internal standard allowed quantitative DPA analysis, plotting the intensity of the strong DPA 1010 cm(-1) band (normalised to the ca. 2120 cm(-1) CNS- band) against DPA concentration gave a linear calibration (R-2 = 0.986) over the range 0 - 50 ppm DPA. The inclusion of thiocyanate also allows false negatives due to accidental deactivation of the enhancing medium to be detected.