359 resultados para 1340
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The twisting growth of a branched polyethylene single crystal formed from the melt was observed directly by means of transmission electron and atomic force miscroscopy. The surface stress asymmetry arising from the asymmetry of the surface-fold structure and, chain tilting resulted in the twisting growth of the single crystals. The handedness of the twisting lamellae was consistent With the chain-tilting direction. When multilayer lamellae piled up in a thicker film, the lamellar twist would be inevitably causing screw dislocations.
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The (1) H and C-13 NMR spectra are reported for Ru(4, 4'-dimethyl-2,2'-bipyridene)(2) (2,2'-bipyridine-4,4'-dicarboxylic acid) (PF6)(2) that can be used as a new electrochemiluminescent probe in immunoasssay and nucleic acid hybridization assay. Because of the effect ol:Ru atom ligands and complex steric configuration, it is difficult to attribute spectra of the title molecular, By using 2D (1) H-(1) H COSY and (1) H-C-13 HETCOR method, the proton and C-13 NMR spectra are assigned completely, which provides a satisfactory method to quantitative and qualitative, analysis of the title moleculer in the further study.
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用~1H NMR和~(13)C NMR谱研究了新型电化学发光探针六氟磷酸二(4,4’-二甲基-2,2’-联吡啶)·(4,4’-二羧酸-2,2’-联吡啶)合钌(Ⅱ)的立体结构,通过~1H~(-1)H COSY、~(13)C~(-1)H HETCOR谱对其氢谱和碳谱中的各谱峰进行了归属,并给出了氢谱和碳谱峰的化学位移值.
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研究了高温高压下x·Li_8SiN_4-0.1(1-x)·Li_3N-0.9(1-x)·BN体系中立方氮化硼(cBN)的转化行为。Li_8SiN_4的存在可显著改善cBN晶体的发育,提高晶体质量。在4.2~5.5GPa,1340~1750℃范围内确定了x=4.8%时体系的cBN转化区,并对转化区内cBN转化率、平均生长速度、成核速度及破碎强度与转化温度和压力的关系进行了研究。
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2007年夏季对黄海冷水团及邻近海域共48个站位的小型底栖动物组成、丰度和生物量,以及环境因子进行了科考研究。所调查站位的小型底栖动物平均丰度达2194 ± 1598 inds./10cm2,其中北黄海17个站位平均丰度为3408 ± 1578 inds./10cm2,南黄海31个站位平均丰度为1529 ± 1121 inds./10cm2。调查站位平均生物量为1839 ± 1289 g dwt/10cm2,其中北黄海站位平均生物量为2760 ± 1340g dwt/10cm2,南黄海平均生物量为1335 ± 902g dwt/10cm2。在分选出的共18个小型底栖动物类群中,丰度上均以自由生线虫占绝对优势,达总量的88%,且在南(88.3%)、北黄海(87.7%)基本无差异。在生物量上,同样以自由生线虫贡献最多(42%),多毛类居次(22%),其他生物量较多的还有桡足类(13%)和甲壳类幼体(12%)。在小型底栖动物的垂直分布上,分布于沉积物表层0-2cm的小型底栖动物占79%,次表层2-5cm占17%,最底层5-8cm仅占4%。统计分析表明研究站位小型底栖动物丰度和生物量与沉积物叶绿素a、有机质含量、中值粒径显著或极显著正相关,与水深呈极显著负相关,此外小型底栖动物生物量与沉积物粉砂粘土含量显著负相关。 同年秋季搭载开放航次对黄海5个站位、东海3个站位、南海2个站位的小型底栖动物组成、丰度和生物量,以及环境因子进行了调查研究。对三个海域小型底栖动物的比较研究发现,平均丰度以黄海最高,达2132 ± 946 inds./10cm2,东海次之,为1954 ± 2047 inds./10cm2,而南海仅156 ± 56 inds./10cm2;三海域的平均生物量依次为2193 ± 1148 g dwt/10cm2、1865 ± 1555 g dwt/10cm2和212 ± 22 g dwt/10cm2。在分选出的共14个小型底栖动物类群中,丰度上均以自由生线虫占绝对优势,分别占总量的85%、89%、85%。在生物量上,黄海以自由生线虫贡献最多(33%),多毛类居次(18%);东海二者比例相近(约37%),而南海则以多毛类占绝对优势(56%),线虫居次(25%)。在小型底栖动物的垂直分布上,三个海区差异较大:分布于沉积物表层0-2cm的小型底栖动物在黄海高达90%,东海仅46%,在南海为63%。统计分析表明,本研究站位小型底栖动物丰度与沉积物中的叶绿素a及脱镁叶绿素a含量和底温呈显著正相关,与水深呈显著负相关。该结果与本航次之后在广东湛江和海南以东的南海海域开展的908调查结果形成了鲜明对照,后者的小型底栖动物及线虫丰度与沉积物中有机质含量呈显著正相关,与水深呈显著负相关,表明近海受人类干扰影响较大。 本文利用微宇宙实验方法,来确定不同浓度梯度的Cu、Pb以及Cu/ Pb混合重金属污染物对青岛湾小型底栖动物(主要是线虫)的影响。加入污染物后,分别在1、3、7、14、21天进行取样分析。结果显示,Cu和Cu/Pb混合高浓度实验单元组的线虫丰度除在第21天有较明显减少外,在整个实验周期内基本没有变化,分析可能系高浓度Cu的固定作用从而使小型底栖动物无法腐烂降解造成的。同一时间尺度上,各重金属污染物实验单元的线虫丰度均高于(或接近于)空白对照组,较高浓度的重金属污染物实验单元的线虫丰度高于(或接近于)较低浓度重金属污染物实验单元,Cu/Pb混合低浓度实验单元的线虫丰度高于同一时间尺度Cu低浓度和Pb低浓度实验单元。推测是由于采样点的线虫群落中存在对Cu和Pb的耐受种或者“机会种”造成的。
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黑潮是西北太平洋一支高温、高盐、高流速的西边界流,它起源于菲律宾以东海域,沿吕宋岛、台湾东岸、东海大陆架外缘流动,并穿越吐噶喇海峡返回太平洋。其中吕宋岛至台湾岛这段西边界流命名为源区黑潮。源区黑潮在流经吕宋海峡以东时,由于失去岸界支撑会发生形变,并通过吕宋海峡与南海环流体系进行质量、动量和能量的交换,并影响着南海的环流特征。因此研究黑潮通过吕宋海峡入侵南海的关键动力过程和机制,对我们国家的军事、生产、环境等具有十分重大的意义,一直是国内外海洋学家关注的焦点。 本文利用高度计资料和涡旋精度的高分辨率数值模式(OFES)输出结果分析了南海东北部和吕宋海峡东侧海域的上层环流特征,并独立建立1.5层浅水约化重力模式下的理想模型,分析了黑潮从吕宋海峡入侵南海的非线性特征和西传的大洋中尺度涡旋与黑潮在吕宋海峡处的相互作用。 对高度计资料和模式结果资料分析的结果表明季风是影响南海北部上层环流的主要因素,黑潮以各种方式入侵南海也是影响南海北部环流特征的重要组成部分。通过数值模拟,我们得到在不同的参数下,黑潮入侵南海会存在稳定态、分叉、周期解等非线性特征,对应着黑潮南海流套、分离流环、无入侵等多种流态。通过讨论大洋中尺度涡旋与黑潮在吕宋海峡处的相互作用,发现涡旋在西传遇到黑潮后基本局地耗散或随黑潮继续向北移动,但当黑潮较弱时,涡旋可能将大洋中的能量通过吕宋海峡传入南海。
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Although respiration of organisms and biomass as well as fossil fuel burning industrial production are identified as the major sources, the CO2 flux is still unclear due to the lack of proper measurements. A mass-balance approach that exploits differences in the carbon isotopic signature (delta(13)C) of CO2 Sources and sinks was introduced and may provide a means of reducing uncertainties in the atmospheric budget. delta(13)C measurements of atmospheric CO2 yielded an average of - 10.3 parts per thousand relative to the Peedee Belemnite standard; soil and plants had a narrow range from -25.09 parts per thousand to -26.51 parts per thousand and averaged at -25.80 parts per thousand. Based on the fact of steady fractionation and enrichment during respiration of mitochondria, we obtained the emission Of CO2 of 35.451 mol m(-2) a(-1) and CO2 flux of 0.2149 mu mol m(-2) s(-)1. The positive CO2 flux indicated the Haibei Alpine Meadow Ecosystem a source rather than a sink. The mass-balance model can be applied for other ecosystem even global carbon cycles because it neglects the complicated process of carbon metabolism, however just focuses on stable carbon isotopic compositions in any of compartments of carbon sources and sinks. (C) 2005 Elsevier B.V. All rights reserved.
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Conventional 3D seismic exploration cannot meet the demand of high yield and high efficiency safe production in coal mine any more. Now it is urgent to improve the discovery degree of coal mine geological structures for coal production in China. Based on 3D3C seismic exploration data, multi-component seismic information is fully excavated. First systematic research on 3D3C seismic data interpretation of coal measure strata is carried out. Firstly, by analyzing the coal measure strata, the seismic-geologic model of coal measure strata is built. Shear wave logging is built by using regression analysis. Horizon calibration methods of PP-wave and PS-wave are studied and the multi-wave data are used together to interpret small faults. Using main amplitude analysis technology, small faults which cannot be found from PP-wave sections can be interpreted from the low frequency PS-wave sections. Thus, the purpose to applying PS-wave data to fine structure assistant interpretation is achieved. Secondly, PP- and PS-wave post-stack well constrained inversion methods of coal measure strata are studied. Joint PP- and PS-wave post-stack inversion flow is established. More attribute parameters, which are applied in fine lithology interpretation of coal measure strata, are obtained from combinations of the inversion results. Exploring the relation between rock with negative Poisson’s ratio and anisotropy, fracture development in coal seam are predicted. Petrophysical features of coal measure strata are studied, and the relations between elastic parameters and lithology, fluid and physical properties are established. Inversions of the physical parameters such as porosity, permeability and water saturation, which reflect lithology and fluid property, are obtained. Finally, the approaches of shear wave splitting and Thomsen parameters inversion, which provide new ideas for seismic anisotropy interpretation of coal measure strata, are studied to predict fracture development. The results of practical application indicate that the methods in this paper have good feasibility and applicability. They have positive significance for high yield and high efficiency safe production in coal mine.
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RESUMO: O objetivo deste trabalho foi avaliar características agronômicos durante o desenvolvimento de híbridos de girassol cultivados na região de Campo Novo do Parecis - MT. O ensaio foi instalado e conduzido,entre os meses de fevereiro ejunho de 2015, na área experimental do setor de produção do Instituto Federal de Educação, Ciência e Tecnologia de Mato Grosso - IFMT Campus Campo Novo do Parecis - MT, cujas coordenadas geográficas são latitude S 13°40'31" longitude O 57°53'31" e altitude média de 574 m. O solo predominante é Latossolo Vermelho distrófico típico. O delineamento experimental foi em blocos casualizados com 13 tratamentos (híbridos) e 4 repetições, totalizando um total de 52 parcelas. Foram avaliadas as seguintes características agronômicas do girassol: dias para o florescimento inicial, dias para a maturação fisiológica, altura de planta, curvatura do caule, número de plantas acamadas, número de plantas quebradas e produtividade de aquênios. Os dados foram submetidos à análise de variância e ao teste de média Scott-Knott (p<0,05). O híbrido BRS G44 apresentou híbrido BRS G44 apresentou bom rendimento, ciclo precoce e porte baixo, nas condições de segunda safra de verão em Campo Novo do Parecis (MT) . Assim, este híbrido se torna boa opção para o cultivo de girassol na região. ABSTRACT: The objective of this study was to evaluate agronomic characteristics for the development of sunflower hybrids grown in the region of Campo Novo do Parecis - MT. The experiment was carried out and conducted between the months of February to June 2015 in the experimental area of the production sector of the Instituto Federal de Educação, Ciência e Tecnologia de Mato Grosso, - IFMT, Campo Novo do Parecis - MT (latitude S 13°40'31" longitude W 57°53'31" and average altitude of 574 m). The predominant soil is Typic Tropudox. The experimental design was randomized blocks with 13 treatments (hybrids) and four repetitions, resulting in 52 plots. The sunflower agronomic traits evaluated were: days to initial flowering, days to physiological maturity, plant height, stem curvature, number of lodged plants, number of broken plants and achenes productivity. Data were subjected to analysis of variance and average test Scott-Knott (p<0.05). The hybrid BRS G44 showed good yield, early maturity and low height in second summer crop conditions in Campo Novo do Parecis (MT). Thus, this hybrid is a good option for sunflower cultivation in the region.
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Dennis, P., Aspinall, R. J., Gordon, I. J. (2002). Spatial distribution of upland beetles in relation to landform vegetation and grazing management. Basic and Applied Ecology, 3 (2), 183?193. Sponsorship: SEERAD RAE2008
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Com o objectivo de conhecer o processo da co-incineração, foram realizadas visitas ao sistema integrado de tratamento e eliminação de resíduos, sA (sisAV), na chamusca, e à cimpor, em souselas. pode concluir-se que o tratamento das emissões gasosas, principal questão conflituosa associada à co-incineração, não difere substancialmente daquele realizado nas instalações onde se procede à queima de combustíveis fósseis, excepto no tocante à instalação de algum equipamento adicional. Não podendo afirmar-se que se trate da solução ideal para a eliminação dos resíduos perigosos, apresenta vantagens como seja o aproveitamento de instalações pré-existentes, ao mesmo tempo que se minimiza a utilização de energia não renovável. Aiming to understand the co-incineration process, the sistema integrado de tratamento e eliminação de resíduos, sA (sisAV), in chamusca, and the cimpor, in souselas, both in portugal, were the two facilities visited to that purpose. It is possible to conclude that the treatment of atmospheric emissions, the main concern associated to conflicts in co-incineration, does not substantially differ from the one used in facilities where fossil fuel is burnt,except in what concerns to some additional equipment that must be installed. though it is not possible to state that this is the ideal solution to solve the hazard waste problem, it has advantages such as the use of pre-existing facilities and, at the same time, the use of nonrenewable energy sources is minimized.
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To investigate the symptom burden experiences of individuals with inflammatory bowel disease (IBD). An explanatory sequential mixed methods study was conducted. A cross-sectional, correlational survey was first undertaken. Symptom burden was measured using a modified disease specific version of the Memorial Symptom Assessment Scale, which was administered to a consecutive sample of individuals with IBD (n = 247) at an IBD Outpatients department in one urban teaching hospital in Ireland. Disease activity was determined using clinical disease activity indices, which were completed by the consulting physician. A sequential qualitative, descriptive study was then conducted aimed at explaining noteworthy quantitative findings. A criterion-related purposeful sample of seven participants from the quantitative study was recruited. Semi-structured face to face interviews were conducted using an interview guide and data were analysed using content analysis. Findings revealed that participants experienced a median of 10 symptoms during the last week, however as many as 16 symptoms were experienced during active disease. The most burdensome symptoms were lack of energy, bowel urgency, diarrhoea, feeling bloated, flatulence and worry. Total symptom burden was found to be low with a mean score of 0.56 identified out of a possible range from 0 to 4. Participants with active disease (M = 0.81, SD = 0.48; n = 68) had almost double mean total symptom burden scores than participants with inactive disease (M = 0.46, SD = 0.43; n = 166) (p < 0.001). Mean total psychological symptom burden was found to be significantly greater than mean total physical symptom burden (rho = 0.73, n = 247, p < 0.001). Self-reported disease control, gender, number of flare ups in the last two years, and smoking status was found to be significant predictors of total symptom burden, with self-reported disease control identified as the strongest predictor. Qualitative data revealed tiredness, pain, bowel symptoms, worry and fear as being burdensome. Furthermore, symptom burden experiences were described in terms of its impact on restricting aspects of daily activities, which accumulated into restrictions on general life events. Psychological symptom burden was revealed as more problematic than physical symptom burden due to its constant nature, with physical and psychological symptoms described to occur in a cyclical manner. Participants revealed that disease control was evaluated not only in terms of symptoms, but also in terms of their abilities to control the impact of symptoms on their lives. This study highlights the considerable number of symptoms and the most burdensome symptoms experienced by individuals with IBD, both during active and inactive disease. This study has important implications on symptom assessment in terms of the need to encompass both physical and psychological symptoms. In addition, greater attention needs to be placed on psychological aspects of IBD care.
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© 2014 by Annual Reviews.Carbon markets are substantial and expanding. There are many lessons from experience over the past 9 years: fewer free allowances, careful moderation of low and high prices, and a recognition that trading systems require adjustments that have consequences for market participants and market confidence. Moreover, the emerging international architecture features separate emissions trading systems serving distinct jurisdictions. These programs are complemented by a variety of other types of policies alongside the carbon markets. This architecture sits in sharp contrast to the integrated global trading architecture envisioned 15 years ago by the designers of the Kyoto Protocol and raises a suite of new questions. In this new architecture, jurisdictions with emissions trading have to decide how, whether, and when to link with one another, and policy makers must confront how to measure both the comparability of efforts among markets and the comparability between markets and a variety of other policy approaches.
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This report provides an overview of water and sediment quality within the Essex Estuaries European Marine Site (EMS) and examines evidence for their influence on biological condition. Site characterisation has been accomplished by review of published literature and unpublished reports, together with interrogation of summary data sets for tidal waters provided by EA.
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An historical data set, collected in 1958 by Southward and Crisp, was used as a baseline for detecting change in the abundances of species in the rocky intertidal of Ireland. In 2003, the abundances of each of 27 species was assessed using the same methodologies (ACFOR [which stands for the categories: abundant, common, frequent, occasional and rare] abundance scales) at 63 shores examined in the historical study. Comparison of the ACFOR data over a 45-year period, between the historical survey and re-survey, showed statistically significant changes in the abundances of 12 of the 27 species examined. Two species (one classed as northern and one introduced) increased significantly in abundance while ten species (five classed as northern, one classed as southern and four broadly distributed) decreased in abundance. The possible reasons for the changes in species abundances were assessed not only in the context of anthropogenic effects, such as climate change and commercial exploitation, but also of operator error. The error or differences recorded among operators (i.e. research scientists) when assessing species abundance using ACFOR categories was quantified on four shores. Significant change detected in three of the 12 species fell within the margin of operator error. This effect of operator may have also contributed to the results of no change in the other 15 species between the two census periods. It was not possible to determine the effect of operator on our results, which can increase the occurrence of a false positive (Type 1) or of a false negative (Type 2) outcome