52 resultados para Drouet, Juliette, 1806-1883.


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Thermal analysis and thermolysis kinetics of three kinds of seaweeds and fir wood (M. glyptostriboides Huet Cheng), a kind of typical land plant, had been conducted. The results showed that thermal stability follows the order of Grateloupia filicina < Ulva lactuca < Dictyopteris divaricata < fir wood. A notable difference on heat flow between seaweeds and fir wood during thermolysis was that the former were mainly connected with exothermic processes at relatively lower temperature regimes. while the latter was connected with an apparent endotherm at a relatively higher temperature regime followed by a maximum exothermic peak. This suggested that the heat coupling might be realized if co-thermolysis of seaweeds and fir wood were carried out. The main devolatilization phase of each seaweed could be described by Avrami-Erofeev equation, which indicated that thermolysis of seaweeds follows the mechanism of random nucleation and nuclei growth, whereas that of fir wood by Z-L-T equation and its thermolysis mechanism was three-dimensional diffusion. The activation energies calculated for both seaweeds and fir wood increase as conversion increases. However, those for the former have wider distribution. (c) 2006 Elsevier Ltd. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

异毛虫科(Paraonidae)和海稚虫科(Spionidae)是环节动物门(Annelida),多毛纲(Polychaeta)中两个常见的科,其成体在海洋生态系统尤其是海洋底栖动物群落中占有重要地位。中国近海异毛虫科和海稚虫科种类极为常见,在潮间带和潮下带均有分布。但由于此两科种类个体小,采集和鉴定困难,在中国一直没有系统的分类学研究。 本论文选择异毛虫科和海稚虫科为研究对象,以中国科学院海洋研究所海洋生物标本馆馆藏的3000余号成体标本为主要研究材料,结合攻读博士学位期间对全国各海域的补充采集标本和从其它单位借用的标本,在认真阅读相关文献和比对某些种类模式标本的基础上,首次对此两科的中国种类进行了全面系统的分类学和地理分布研究。结果如下: 1. 本文记述了中国海域异毛虫科4属18种,其中包括3新纪录种;海稚虫科16属39种,包括7新种,10新纪录种。各鉴定种类均进行了详细的分类学特征描述,并附有形态学结构图。对罕见种类的标本和保存状况较差、光学显微镜无法获得可靠分类学信息的标本进行了扫描电镜观察,并拍摄有电镜照片。 2. 对中国海域有关异毛虫科和海稚虫科种类记录进行了系统的分类学修订,澄清了部分种类特别是一些常见种类分类学研究中存在的错误和混淆。(1)通过大量阅读文献和反复比较检查标本,认为以前我国文献记录的海稚虫科奇异稚齿虫属的奇异稚齿虫Paraprionospio pinnata (Ehlers, 1901)实际包括3种,即扭鳃奇异稚齿虫Paraprionospio inaequibranchia (Caullery, 1914)、枫香树奇异稚齿虫Paraprionospio coora Wilson, 1990和冠奇异稚齿虫Paraprionospio cristata sp. nov.,其中扭鳃奇异稚齿虫和枫香树奇异稚齿虫在中国海属首次记录,冠奇异稚齿虫为一新种。枫香树奇异稚齿虫主要分布于黄海,其分布南界为121°30′ E, 34°30′ N, 扭鳃奇异稚齿虫分布于南海,其分布北界为114°00′ E, 21°45′ N,冠奇异稚齿虫分布区域较广,从长江口到南海的沿岸水域均有分布。奇异稚齿虫是分布在智利、南加利福尼亚、西墨西哥(可能还有安哥拉)的种,在我国海域未见分布。(2)将在我国北方沿海非常常见但长期被记录为鳞腹钩虫Scolelepis (Scolelepis) squamata (Müller, 1806)(海稚虫科)的标本重新鉴定为一个新种,即红纹腹钩虫Scolelepis (Scolelepis) daphoinos sp. nov.;鳞腹钩虫分布于北大西洋和地中海沿岸水域,在我国海域未见分布。(3)明确了中国海Prionospio steenstrupi复合体种类。此复合体所包含的种类在形态上十分相似,分类学研究时极易混淆。在已有的文献记录中,该复合体中国种类包括两种,玛氏稚齿虫Prionospio (Prionospio) malmgreni Claparède, 1870和西沙稚齿虫Prionospio (Prionospio) sishaensis Wu & Chen, 1964。本文将该复合体中国种类修正为5种,分别是包氏稚齿虫Prionospio (Prionospio) bocki Söderström, 1920、开普敦稚齿虫Prionospio (Prionospio) dubia Maciolek, 1985、太平洋稚齿虫Prionospio (Prionospio) pacifica sp. nov.、欢乐稚齿虫Prionospio (Prionospio) paradisea Imajima, 1990和西沙稚齿虫Prionospio (Prionospio) sishaensis Wu & Chen, 1964。现在大多数分类学者认为玛氏稚齿虫是一个不可鉴定种,该种的原始描述可能包括数种,且模式标本已丢失。(4)将中国海记录的矮小离稚齿虫Apoprionospio pygmaea (Hartman, 1961)更正为卡米拉离稚齿虫Apoprionospio kirrae Wilson, 1990;将中国海记录的科氏光稚虫Spiophane kroyeri Grube, 1860更正为深蓝光稚虫Spiophanes fuscatus sp. nov.。 3. 比较研究了中国海域异毛虫科和海稚虫科的区系特点,详细分析了两科中国海种类的组成。认为中国种类在区系组成上属于印度-马来区系,异毛虫科中国海特有种较少,仅2种,占该科中国种数的11%;而海稚虫科中国海特有种较多,共9种,占该科中国种数的23%。中国海异毛虫科种类组成和日本、俄罗斯附近水域的组成较为相似,中国海海稚虫科种类组成和日本、澳大利亚附近水域的组成较为相似。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A new species of Spionidae, Scolelepis (Scolelepis) daphoinos sp. nov., is described and illustrated from northern China seas. The species was frequently encountered and highly abundant on sand beaches, but rarely found in subtidal areas. It was formerly misidentified as S. (S.) squamata (Muller, 1806) in China but differed from the latter species in several details in morphology, including the presence of obvious reddish pigmentation patches and the absence of unidentate hooded hooks. Another two Scolelepis species, S. (S.) lingulata Imajima, 1992 and S. (S.) variegata Imajima, 1992, are reported for the first time from Chinese waters. Two species of Scolelepis, S. (S.) globosa Wu & Chen, 1964 and S. (S.) lefebvrei (Gravier, 1905), were reported previously; therefore, five species in this genus are known from China in total. A key to all Scolelepis species from Chinese waters is provided.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Seven new sesquiterpenes (1-7), together with seven known sesquiterpenes, aplysin (8), aplysinol (9), gossonorol (10), 7,10-epoxy-ar-bisabol-11-ol (11), 10-epi-7,10-epoxy-ar-bisabol-11-ol (12), johnstonol (13), and laurebiphenyl (14), have been isolated from the red alga Laurencia tristicha. The structures of new compounds were established as laur-11-en-2,10-diol (1), laur-11-en-10-ol (2), laur-11-en-1,10-diol (3), 4-bromo-1,10-epoxylaur-11-ene (4), cyclolauren-2-ol (5), laurentristich-4-ol (6), and ar-bisabol-9-en-7,11-diol (7) by means of spectroscopic methods including IR, HRMS, and ID and 21) NMR techniques. Compound 6 possessed a novel rearranged skeleton. All compounds were tested against several human cancer cell lines including lung adenocarcinoma (A549), stomach cancer (BGC-823), hepatoma (Bel 7402), colon cancer (HCT-8), and HELA cell lines. Laurebiphenyl (14) showed moderate cytotoxicity against all tested cell lines, with IC50 values of 1.68, 1.22, 1.91, 1.77, and 1.61 mu g/mL, respectively. Other compounds were inactive (IC50 > 10 mu g/mL).

Relevância:

10.00% 10.00%

Publicador:

Resumo:

本文简要介绍了光学触觉传感器阵列的用途和特点,并对各种类型的结构、原理和存在问题作了较详细的分析说明。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

As powerful tools to study the lithosphere dynamics, the effective elastic thickness (Te) as well as the envelope of yielding stress of lithosphere have been attracted great attention of geoscientists in the past thirty years. The oceanic lithosphere, contrary to the continental lithosphere, has more fruits for its simple structures and evolution process. In continent, the lithosphere commonly is complex and variable in the rheological, thermal structures, and has a complicated history. Therefore, the application of the effective elastic thickness in continent is still a subject to learn in a long time. Te, with the definition of the thickness of an elastic plate in theory flexured by the equal benging of the real stress in the lithosphere plate (Turcotte, 1982), marks the depth of transition between elastic and fluid behaviors of rocks subjected to stress exceeding 100 MPa over the geological timescales (McNutt, 1990). There are three methods often adapted: admittance or isostatic response function, coherence and forwarding. In principle, the models of Te consist of thermal-rheological, non-linear Maxwell, non-linear work hardening and rheological layered models. There is a tentative knowledge of Te that it is affected by the following factors: crustal thickness, crust-mantle decoupling, plate bending, boundary conditions of plate (end forces and bending moments), stress state, sedimentary layer, faulting effect, variation in the mountain belts' strike, foreland basin, inheritance of tectonic evolution, convection of mantle, seismic depth and lithosphere strength. In this thesis, the author introduces the geological sketch of the Dabie collisional orogenic belt and the Hefei Basin. The Dabie Mts. is famous for the ultra-high pressure metamorphism. The crustal materials subducted down to the depth of at least 100 km and exhumed. So that the front subjects arise such as the deeply subduction of continent, and the post-collisional crust-mantle interaction. In a geological journey at June of 1999, the author found the rarely variolitic basaltic andesite in the Dabie Mts. It occurs in Susong Group, near Zhifenghe Countryside, Susong County, Anhui Province. It is just to the south of the boundary between the high-grade Susong melange and the ultra-high grade South Dabie melange. It has a noticeable knobby or pitted appearance in the surface. The size of the varioles is about 1-4 mm. In hand-specimen and under microscope, there are distinct contacts between the varioles and the matrice. The mineralogy of the varioles is primarily radiate plagioclase, with little pyroxene, hornblende and quartz. The pyroxene, hornblende and quartz are in the interstices between plagioclase. The matrix is consisted of glass, and micro-crystals of chlorite, epidote and zoisite. It is clearly subjected and extensive alteration. The andesite has an uncommon chemical composition. The SiO_2 content is about 56.8%, TiO_2 = 0.9%, MgO = 6.4%, (Fe_2O_3)_(Total) = 6.7% ~ 7.6%, 100 Mg/(Mg+Fe) = 64.1 ~ 66.2. Mg# is significantly high. The andesite has higher abundances of large-lithophile trace elements (e.g. K, Ba, Sr, LREE), e.g. La/Nd = 5.56-6.07, low abundances of high-strength-field elements (HFSE, e.g. Ta, Nb, P, Ti), particularly Ta and Nb strongly depleted. These are consistent with the characteristics of subducted-related magmas (Pearcce, 1982; Sun and McDonaugh, 1989). In the spider diagram of trace elements, from Ce to right hand, the abundances of elements decrease quickly, showing a characteristic of the continental margins (Pearce, 1982). There has a strongly enrichment of light-rare-earth elements, with a significant diffraction of REEs (the mean value of (La/Yb)_N is 32.84). No Eu anomaly, but there are anomaly high (La/Yb)_N = 28.63-36.74, (La/Y)_N = 70.33 - 82.84. The elements Y and Yb depleted greatly, Y < 20 ppm, Y_N = 2.74-2.84, Yb_N = 2.18 - 2.35. From the La-(La/Sm) diagram, the andesite is derived from partial melting. But the epsilone value of Nd is -18.7 ~ -19.2, so that the material source may be the mantle materials affected by the crustal materials. The Nd model age is 1.9 Ga indicating that the basaltic andesite was resulted from the post-collisional crust-mantle interaction between the subducted Yangze carton and the mantle of Sino-Korea carton. To obtain the Te of the lithosphere beneath the Dabie Mts. and the Hefei Basin, the author applies the coherence method in this thesis. The author makes two topography-gravity profiles (profiles 7~(th) and 9~(th)) across the Dabie Mts. and the Hefei Basin, and calculates the auto-coherence, across coherence, power spectrum, across power spectrum of the topography and gravity of the two profiles. From the relationships between the coherence and the wave-number of profiles. From the relationships between the coherence and the wave-number of profiles 7~(th) and 9~(th), it is obtained that the characteristic wavelengths respectively are 157 km and 126 km. Consequently the values of effective elastic thickness are 6.5 km and 4.8 km, respectively. However, the Te values merely are the minimum value of the lithosphere because the coherencemethod in a relative small region will generate a systemic underestimation. Why there is a so low Te value? In order to check the strength of the lithosphere beneath the Dabie Mts., the authore tries to outline the yielding-stress envelope of the lithosphere. It is suggested that the elastic layers in the crust and upper mantle are 18 km and 35 km, respectively. Since there exist a low viscosity layer about 3-5 km thickness, so it is reasonable that the decoupling between the crust and mantle occurred. So the effective thickness of the lithosphere can be estimated from the two elastic layers. Te is about 34 km. This is the maximum strength of the lithosphere. We can make an approximately estimation about the strength of the lithosphere beneath the Dabie Mts.: Te is about 20-30 km. The author believes that the following factors should be responsible for the low Te value: (1) the Dabie Mts. has elevated strongly since K_3-J_1. The north part of the Dabie Mts. elevates faster than the south part today; (2) there occur large active striking faults in this area. And in the east, the huge Tan-Lu striking fault anyway tends to decrease the lithosphere strength; (3) the lithosphere beneath the Dabie Mts. is heter-homogeneous in spatio-temporal; (4) the study area just locates in the adjacent region between the eastern China where the lithosphere thickness is significantly reduced and the normal western China. These factors will decrease the lithosphere strength.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

对河水样品中低含量硼的分离方法及硼同位素组成的测定进行了研究。将约1000mL河水样品分别用硼特效树脂,混合树脂富集和纯化后,紫外灯照射去除有机质,蒸发浓缩至小体积,采用正热离子质谱法进行硼同位素组成的测定。全流程回收率在95%以上,同位素稀释法测得全流程空白为41ng。经该方法处理后的样品能满足同位素质谱测定的需要。不产生同位素分馏,测试精度基本在0.6‰以内。