35 resultados para Vespasiano, Emperador de Roma, 9-79.

em Chinese Academy of Sciences Institutional Repositories Grid Portal


Relevância:

100.00% 100.00%

Publicador:

Resumo:

本论文采用第三代超分子受体化合物——磺化硫杂杯芳烃(简称TCAS)作为活性组分,将其加载到树脂载体上,制成一种新型的TCAS吸附树脂。借助红外光谱、紫外光谱、核磁共振和电喷雾质谱等检测分析手段对TCAS吸附树脂及其制备的中间产物进行表征。采用静态批试验方法研究发现TCAS吸附树脂对重金属和卤代烃类有机物都有较好的吸附去除效果,其对Pb2+、Cd2+、Cu2+和Zn2+四种重金属的吸附容量分别达到26.32mg•g-1、18.12mg•g-1、12.24mg•g-1和6.85mg•g-1;对二氯甲烷、三氯甲烷、四氯化碳、三氯乙烯四种卤代烃的吸附容量分别为9.23 mg•g-1、7.92 mg•g-1、6.73 mg•g-1和4.34 mg•g-1。并发现温度、树脂用量和溶液pH值等因素能影响TCAS吸附树脂的吸附去除效果。同时研究了TCAS吸附树脂对污染物的吸附优先性规律、动力学规律和热力学规律。采用化学计量学分析TCAS络合重金属的紫外光谱,获得了TCAS-重金属络合物的纯紫外光谱,以及TCAS、TCAS-重金属络合物随重金属浓度变化的分布曲线,并最终解析得到TCAS与Cu、Zn、Cd和Pb的络合常数(lgβ)分别为9.79、8.72、6.87和5.00。通过多次吸附试验,考察了TCAS吸附树脂回收循环利用的可行性,发现TCAS吸附树脂可进行多次循环回收再利用。

Relevância:

100.00% 100.00%

Publicador:

Resumo:

蒙古栎(Quercus mongolica)、花曲柳(Fraxinus rhynchophulla)和胡桃楸(Juglans mandshurica)林是我国东北天然次生林区具有代表性的主要林型。本研究以该3种林型为对象,利用数码相机外带鱼眼镜头获得3种林型的半球面影像,再利用专用软件Gap Light Analyzer处理分析获得了叶面积指数、林冠孔隙度和林下光照因子等参数。结果表明,3种林型的叶面积指数变化总体趋势是一致的,均呈先上升再下降的单峰曲线,蒙古栎林和胡桃楸林都是在7月中旬或8月中旬达到最大峰值,花曲柳林是在8月中旬或9月中旬达到最大峰值;3种林型冠层孔隙度的变化总体趋势也是一致的,呈先下降再上升的单峰曲线,不同样地峰值出现的时间也不同,最低峰值在6、7、8、9月中旬均有出现;通过对不同月份的叶面积指数、林下散射光、林下直射光的变异系数分析表明,7—9月叶面积指数的空间格局是影响林下散射光空间分布的主要因素。叶面积指数与林冠孔隙度呈指数相关。

Relevância:

100.00% 100.00%

Publicador:

Resumo:

根据天然草地退化程度的差异,采用松耙+补播+施肥+封育(退化较严重的草地)、封育+施肥(轻度退化草地)等措施,植物群落物种组成、多样性等特征值及其植被盖度发生明显变化.研究第2年结果表明,物种数封育+施肥处理最高(32种),对照居中(26种),补播+施肥处理最低(13种);多样性指数大小依次为封育+施肥(3.126)、对照(2.819)、补播+施肥(1.494);均匀度指数大小依次为封育+施肥(0.902)、对照(0.865)、补播+施肥(0.582);群落总盖度大小依次为封育+施肥(85.9%)、补播+施肥(79.7%)、对照(72.9%);补播+施肥+封育处理后地上生物量最大(460.65 g/m2),原生植被+封育+施肥处理居中(310.14 g/m2),对照最低(178.96 g/m2);地下生物量大小依次为封育+施肥(6 920.37 g/m2)、补播+施肥(1 458.96 g/m2)、对照(828.91 g/m2);补播+施肥+封育处理优良牧草较对照提高近50倍,杂草类减少82.81%,封育+施肥处理较对照良牧草比例提高48倍,杂草类比例减少80.46%.半人工草地通过灭除杂草和施肥相结合的示范试验表明:单纯进行灭杂,地上生物量减少,灭杂和施肥相结合不仅可提高地上生物量,而且可提高优良牧草的比例;不同处理区土壤养分含量各不相同,其中封育+施肥处理全氮、全碳、有机碳最高,对照居中,补播+施肥较低.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Low-temperature heat capacities of the 9-fluorenemethanol (C14H12O) have been precisely measured with a small sample automatic adiabatic calorimeter over the temperature range between T = 78 K and T = 390 K. The solid-liquid phase transition of the compound has been observed to be T-fus = (376.567 +/- 0.012) K from the heat-capacity measurements. The molar enthalpy and entropy of the melting of the substance were determined to be Delta(fus)H(m) = (26.273 +/- 0.013) kJ (.) mol(-1) and Delta(fus)S(m) = (69.770 +/- 0.035) J (.) K-1 (.) mol(-1). The experimental values of molar heat capacities in solid and liquid regions have been fitted to two polynomial equations by the least squares method. The constant-volume energy and standard molar enthalpy of combustion of the compound have been determined, Delta(c)U(C14H12O, s) = -(7125.56 +/- 4.62) kJ (.) mol(-1) and Delta(c)H(m)degrees(C14H12O, s) = -(7131.76 +/- 4.62) kJ (.) mol(-1), by means of a homemade precision oxygen-bomb combustion calorimeter at T = (298.15 +/- 0.001) K. The standard molar enthalpy of formation of the compound has been derived, Delta(f)H(m)degrees (C14H12O, s) = -(92.36 +/- 0.97) kJ (.) mol(-1), from the standard molar enthalpy of combustion of the compound in combination with other auxiliary thermodynamic quantities through a Hess thermochemical cycle. (C) 2004 Elsevier Ltd. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

概述了第9届国际等离子体化学会议的论文和活动情况,对这个领域的发展提出了一些看法。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A rapid detection and identification of pathogens is important for minimizing transfer and spread of disease. A label-free and multiplex biosensor based on imaging ellipsometry (BIE) had been developed for the detection of phage M13KO7. The surface of silicon wafer is modified with aldehyde, and proteins can be patterned homogeneously and simultaneously on the surface of silicon wafer in an array format by a microfluidic system. Avidin is immobilized on the surface for biotin-anti-M13 immobilization by means of interaction between avidin and biotin, which will serve as ligand against phage M13KO7. Phages M13KO7 are specifically captured by the ligand when phage M13KO7 solution passes over the surface, resulting in a significant increase of mass surface concentration of the anti-M13 binding phage M13KO7 layer, which could be detected by imaging ellipsometry with a sensitivity of 10(9) pfu/ml. Moreover, atomic force microscopy is also used to confirm the fact that phage M13KO7 has been directly captured by ligands on the surface. It indicates that BIE is competent for direct detection of phage M13KO7 and has potential in the field of virus detection. (C) 2008 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A new dye, 2,7-bis(4-methoxystyryl)-9,9-bis(2-ethylhexyl)-9H-fluorene, has been synthesized, which is a D-pi-D symmetrical-type fluorene derivative. The two-photon absorption (TPA) of this new dye has been experimentally studied by comparable two-photon-induced fluorescence method. This new dye has a TPA cross-section of 84 x 10(-50) cm(4) s/photon at 790 nm/13 fs. (c) 2004 Elsevier GmbH. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

abstract {A large-mode-area (LMA) multimode fiber before and after coiling was studied contrastively in the experiment. Single-transverse-mode output was achieved when the fiber laser was coiled around a mandrel of 65 mm radius. After coiling, beam quality factor of the laser dropped from 1.24 to 1.06 and slope efficiency dropped from 64.7% to 54.3%. When the launched pump power was 149 W, the corresponding output power was 94.7 W and 79.4 W, respectively. However, the brightness of the coiled fiber laser was 1.15 times that of the uncoiled. Coiled modal losses of different modes were also calculated for the fiber employed in the experiment. The measured results agree well with the calculated ones.}

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador: