交联对聚己二酸乙二醇酯聚氨酯/甲基丙烯酸甲酯交联聚合物的力学阻尼、相容性及形态的影响

用紫外光聚合方法制备出一系列端乙烯基聚己二酸乙二醇酯聚氨酯(PEAPU)和甲基丙烯酸甲酯(MMA)AB交联聚合物(ABCP)。用粘弹谱仪、透射电子显微镜(TEM)和平衡溶胀法研究了AB交联聚合物的动态力学性能、玻璃化转变温度、形态和交联密度、观察到相应于聚氨酯和PMMA相两个玻璃化转变温度,TEM照片中的微相分离是更明显的,ABCP中的两个T_g内移表明,两种成分的化学交联增加了相互的可混性、与ABCP具有相同组成的IPN有比ABCP大得多的相区。氢键能够影响ABCP的相容性、形态和动态力学性能。

The variability of eddy kinetic energy in the South China Sea deduced from satellite altimeter data

We used fifteen years (1993-2007) of altimetric data, combined from different missions (ERS-1/2, TOPEX/Poseidon, Jason-1, and Envisat), to analyze the variability of the eddy kinetic energy (EKE) in the South China Sea (SCS). We found that the EKE ranged from 64 cm(2)/s(2) to 1 390 cm(2)/s(2) with a mean value of 314 cm(2)/s(2). The highest EKE center was observed to the east of Vietnam (with a mean value of 509 cm(2)/s(2)) and the second highest EKE region was located to the southwest of Taiwan Island (with a mean value of 319 cm(2)/s(2)). We also found that the EKE structure is the consequence of the superposition of different variability components. First, interannual variability is important in the SCS. Spectral analysis of the EKE interannual signal (IA-EKE) shows that the main periodicities of the IA-EKE to the east of Vietnam, to the southwest of Taiwan Island, and in the SCS are 3.75, 1.87, and 3.75 years, respectively. It is to the south of Taiwan Island that the IA-EKE signal has the most obvious impact on EKE variability. In addition, the IA-EKE exhibit different trends in different regions. An obvious positive trend is observed along the east coast of Vietnam, while a negative trend is found to the southwest of Taiwan Island and in the east basin of Vietnam. Correlation analysis shows that the IA-EKE has an obvious negative correlation with the SSTA in Nio3 (5A degrees S-5A degrees N, 90A degrees W-150A degrees W). El Nio-Southern Oscillation (ENSO) affects the IA-EKE variability in the SCS through an atmospheric bridge-wind stress curl over the SCS. Second, the seasonal cycle is the most obvious timescale affecting EKE variability. The locations of the most remarkable EKE seasonal variabilities in the SCS are to the east of Vietnam, to the southwest of Taiwan, and to the west of Philippines. To the east of Vietnam, the seasonal cycle is the dominant mechanism controlling EKE variability, which is attributed primarily to the annual cycle there of wind stress curl. In this area, the maximum EKE is observed in autumn. To the southwest of Taiwan Island, the EKE is enlarged by the stronger SCS circulation, which is caused by the intrusion branch from the Kuroshio in winter. Finally, intra-annual and mesoscale variability, although less important than the former, cannot be neglected. The most obvious intra-annual and mesoscale variability, which may be the result of baroclinic instability of the background flow, are observed to the southwest of Taiwan Island. Sporadic events can have an important effect on EKE variability.

末次冰消期以来东亚季风演化：来自东海和北黄海沉积孢粉记录

本论文通过对冲绳海槽南部的MD05-2908孔、北黄海的B-U35、B-U41、B-L44孔和北黄海的299份表层样中的孢粉组成、堆积速率、有机碳氮同位素的综合研究，分析了北黄海的孢粉来源、传播动力和途径，并与其它古气候记录对比，重建了末次冰消期以来东亚季风的演化。 MD05-2908孔孢粉组合特征显示6800-3800a BP间气候温暖干燥，其间存在着两次明显的温度降低、湿度增加阶段，即6800-6600a BP和5800-4850a BP；3800a BP以后，气候变得比较寒冷湿润，中世纪暖期和小冰期分别位于990-480a BP和480-230a BP。 北黄海表层孢粉百分含量等值线图显示北黄海不同海域孢粉来源不同，北黄 海东部海域(123.5°E以东的陆架区域)孢粉主要来源于鸭绿江；北黄海中部海域(123.5°E-122.6°E的陆架区域)孢粉来源比较复杂，既有来自辽东半岛、沿海岛屿、山东半岛，还有由黄海暖流携带而来的；北黄海西部海域(122.6°E以西的陆架区域)孢粉以黄海沿岸流携带而来的黄河来源的为主。 北黄海表层孢粉百分含量等值线图还显示，北黄海东部海域孢粉分布主要受 鸭绿江冲淡水影响，波浪和潮汐的作用较弱；北黄海中部海域孢粉分布受黄海暖流和辽东沿岸流的分支共同影响；黄海暖流与黄海沿岸流在山东半岛东北部相遇，形成一逆时针方向的涡旋，该涡旋控制着北黄海西部海域孢粉的分布。 B-U35孔、B-U41和B-L44孔孢粉组合特征显示，12830-12350a BP时气候 寒冷干燥，植被以旱生草本植物为主，时间上可能对应YD事件；12350-10100a BP时植被以针叶林为主，林下生长着大量蕨类植物，气候寒冷湿润，可能对应着YD事件；10100-6600a BP时植被以落叶阔叶林为主，伴生大量旱生草本植物，气候温暖干燥；6600-5000a BP时植被以针叶-落叶阔叶混交林为主，旱生草本植物含量下降，相对上一阶段温度有所降低，但气候更湿润，可能对应全新世最佳期；5000-4000a BP时针叶林所占比例扩大，温度再次降低，湿度变化不明显；4000-500a BP旱生草本植物含量增加，气候寒冷干燥；500a BP-至今，受人类活动影响，植被遭到严重破坏。 B-U35孔和B-U41孔淡水水生植物花粉百分含量曲线显示11750a BP以来黄河河口地区沼泽湿地面积几经变化。10100-6600a BP时沼泽湿地范围在上一阶段的基础上进一步扩大；6600-2850a BP间沼泽湿地大面积缩小，水生植物属种式微；2850a BP之后黄河河口地区沼泽湿地面积再次扩大，水生植物重新繁盛。 MD05-2908孔蕨类孢子百分含量被用来作为中国东南部季风演化的代用指标。结果显示6800-3800a BP时夏季风较强，其间有两次夏季风减弱阶段，分别位于6800-6600a BP和5800-4850a BP，3800a BP以来，夏季风明显减弱，此期的夏季风减弱除受太阳辐射量的减少影响外，可能还与El Nino的频繁爆发有关。 B-U35孔和B-U41孔蒿属、藜科、麻黄科百分含量被用来作为中国中北部夏季风演化的代用指标。研究表明，11750a BP以来东亚夏季风强度在10100-6600a BP时，显著加强，6600a BP左右，夏季风开始减弱，4000a BP以后夏季风显著减弱。 将MD05-2908孔、B-U35孔和B-U41孔夏季风代用指标进行对比发现，中晚全新世以来中国南-北湿度变化特征正好相反，东亚夏季风强度变化以及由此引起的雨锋的南进北撤可能是导致中国不同区域中晚全新世以来降雨量不同的主要原因。

Chromosome inheritance in triploid Pacific oyster Crassostrea gigas thunberg

Reproduction and chromosome inheritance in triploid Pacific oyster (Crassostrea gigas Thunberg) were studied in diploid female x triploid male (DT) and reciprocal (TD) crosses. Relative fecundity of triploid females was 13.4% of normal diploids. Cumulative survival from fertilized eggs to spat stage was 0.007% for DT crosses and 0.314% for TD crosses. Chromosome number analysis was conducted on surviving progeny from DT and TD crosses at 1 and 4 years of age. At Year 1, oysters from DT crosses consisted of 15% diploids (2n = 20) and 85% aneuploids. In contrast, oysters from TD crosses consisted of 57.2% diploids, 30.9% triploids (3n = 30) and only 11.9% aneuploids, suggesting that triploid females produced more euploid gametes and viable progeny than triploid males. Viable aneuploid chromosome numbers included 2n + 1, 2n + 2, 2n + 3, 3n - 2 and 3n - 1. There was little change over time in the overall frequency of diploids, triploids and aneuploids. Among aneuploids, oysters with 2n + 3 and 3n-2 chromosomes were observed at Year 1, but absent at Year 4. Triploid progeny were significantly larger than diploids by 79% in whole body weight and 98% in meat weight at 4 years of age. Aneuploids were significantly smaller than normal diploids. This study suggests that triploid Pacific oyster is not completely sterile and cannot offer complete containment of cultured populations.

Study on cytocompatibility of carboxymethyl-chitosan membranes to skin fibroblasts

Chitosan and carboxymethl-chitosan (CM-chitosan) membranes with different molecular mass were prepared by a casting method. The cytocompatibility of two kinds of polysaccharide membranes to skin fibroblasts that cultured in vitro were studied. The methods were to culture the cells in soaking fluid of membranes and to culture the cells on the membranes directly. The results showed that the soaking fluid had no toxicity to fibroblasts and the biological security of lower molecular mass membranes were better than higher molecular mass membranes, and CM-chitosan membranes were better than chitosan membranes. In addition, the growth of fibroblasts on chitosan membranes was inhibited and the cells would fall off from chitosan membranes after a period of culture. However, the cells adhered and expanded well on CM-chitosan membranes. All these demonstrated that cytocompatibility of CM-chitosan membranes to skin fibroblasts was better than chitosan membranes.

Radioactivity Concentrations in Soils in the Qingdao Area, China

The specific activity concentrations of radionuclides U-238, Th-212, and K-40 of 2300 sampling points in the Qingdao area were measured by an FD-3022 gamma-ray spectrometer. The radioactivity concentrations of U-238, Th-232, and K-40 ranged from 3.3 to 185.3, from 6.9 to 157.2, and from 15.8 to 7834.4 Bq kg(-1), respectively. The air-absorbed dose at I meter above ground, effective annual dose, external hazard index, and radium equivalent activity were also calculated to systematically evaluate the radiological hazards of the natural radioactivity in Qingdao. The air-absorbed dose, effective annual dose, external hazard index, and radium equivalent activity in the study area were 98.6 nGy h(-1), 0.12 mSv, 0.56, 197 Bq kg(-1), respectively. Compared with the worldwide value, the air-absorbed dose is slightly high, but the other factors are all lower than the recommended value. The natural external exposure will not pose significant radiological threat to the population. In conclusion, the Qingdao area is safe with regard to the radiological level and suitable for living.

牦牛的分类学地位及起源研究:mtDNA D-loop序列的分析

牦牛的起源与属级分类学地位至今仍然存在一定的争议.我们测定了家养牦牛和野生牦牛线粒体控制区(D-loop)序列,并以此构建牦牛和牛属、野牛属、水牛属以及非洲水牛属相关种的系统发育树.研究结果表明线粒体D-loop区与Cyt b基因序列在构建牛族的系统发育具有同样重要的价值.系统发育关系显示野牛属的灭绝种草原野牛与现存种美洲野牛先聚合为一单系群,然后再和牦牛形成一单系分支,表明牦牛与野牛属的草原野牛、美洲野牛亲缘关系最近,具有最近的共同祖先,而与牛属的其它亚洲物种亲缘关系较远.因此,本研究不支持将牦牛独立为牦牛属--Poephagus,牛属与野牛属在分类上也应合并为一个属.基于上述研究结果和化石证据,我们进一步对牦牛起源的历史背景进行了讨论,认为牦牛与野牛属的分化是由于第四纪气候变化在欧亚大陆发生的,野牛通过白令陆桥进入北美;冰期结束后,由于欧亚大陆其它地区温度升高,牦牛只能局限分布在较为寒冷的青藏高原;而野牛属在北美先后分化为草原野牛和美洲野牛,前者可能是后者的直接祖先.

青海省春小麦收割后田间堆放期间产量与品质的变化

为了解青海省春小麦收割后田间堆放期间产量和品质的变化，选择近年育成的春小麦品种“高原205”（白粒，易穗发芽）、“高原115”（紫黑色小麦）、“高原448”（红粒）和“高原314”（白粒）以及曾为青海省主栽品种的“青春533”（红粒）为材料，收割后以农民常用的田间堆放方式进行堆放，每隔9d对其进行采样，测定产量、SDS沉淀值和降落数值的变化。结果表明，随着堆放时间的延长，收获产量逐步下降，平均产量从第1次采样（Od）时的504g／m^2减少到63d后的384g／m^2，收获产量平均值与取样时间直线回归F值为20．91，大于F0.01（6．90）；SDS沉淀值变化较小，F值为0．90，小于F0．05（2．13）；降落数值在取样时间点上差异极显著．F值等于46，72，大于F0.01（2．87）。高原205的降落数值一直呈现下降趋势，而高原448、高原115、高原314和青春533的变化是在O～18d间上升，然后下降。总体而言，田间堆放对收获产量和品质不利。

稳定性同位素技术在生态学上的应用

稳定性同位素技术早在20世纪70年代末期就被引入到生态学领域.最初是利用植物稳定性碳同位素的差异,开展了许多有关营养流动方面的研究;到90年代,稳定性碳和氮同位素被用来分析动物的食性、营养级位置关系以及食物链结构;本世纪初,由于技术的进步,稳定性同位素(特别是氢同位素)被用来开展动物迁徙习性方面的研究.到目前为止,国内有关这方面的研究还鲜有报道,而且对自然界存在的稳定性同位素的理解还存在一定偏差.本文主要介绍了稳定性同位素效应及其分馏原理、稳定性同位素在示踪动物食性信息、确定营养级位置关系、分析食物网结构以及研究动物迁徙生态学中的作用等方面的内容.

贵州岩溶地区岩性与土地石漠化的相关分析

在构筑1：50万贵州岩溶地区岩石组合类型分布图的基础上，以GIS为分析手段，对贵州省石漠化分布图和地层岩性图进行了空间分析，探讨了各类岩性与不同级别石漠化之间的相关关系。石漠化与岩性具有明显的相关性，强度石漠化主要分布在纯质碳酸盐岩地区，尤其是纯质灰岩地区；中度石漠化在白云岩组合中的比例较灰岩组合中高；轻度石漠化在碳酸盐岩与碎屑岩夹层和互层中分布较广；石漠化与纯碳酸盐岩相关关系最明显.

埋藏后生作用对生物壳体^87Sr／^86Sr的影响研究

根据小渡口剖面２８层有孔虫、介形虫、腹足类生物壳体的微观观察、微量元素及其比值、＾８７Ｓｒ／＾８６Ｓｒ与微量元素特征对比经及水－岩反应＾８７Ｓｒ／＾８６Ｓｒ的混合模式，显示生物壳体遭受了埋藏后生作用，但对生物壳体原始的＾８７Ｓｒ／＾８６Ｓｒ比值基本没有改变或影响甚微，推测参与埋藏后生作用的流体与生物壳体具有相近的Ｓｒ同位素组成或较悬殊的Ｓｒ含量。同时，实际研究表明评价和判别埋藏后生作用对生物壳体原

土壤中重金属的生物有效性研究进展

综述了近十年来国内及国际上研究土壤重金属的生物有效性的态势，尤其是影响土壤中重金属生物有效性的诸多因素，以期进一步推进国内的重金属生物有效性的研究工作和重金属污染土壤的生物治理工作。

未熟—低熟油流体特征——以济阳坳陷古近系为例

对济阳坳陷古近系储层中流体包裹体的研究进一步证明,其油气属未熟—低熟油气。除了油藏埋深浅、地层时代新、为自生自储同生油藏外,还具下列特征:油气生成温度低,包裹体均一温度范围为53～115 ℃;处于低演化阶段,储层中主要的包裹体类型是纯液态烃包裹体及纯液体盐水溶液包裹体。包裹体烃类成分中重烃及丁烷含量高,重烃平均占总烃的52. 14 % ,丁烷平均占总烃的14. 46 %;流体压力高,估算的流体压力范围是10. 0～40. 5 MPa ;盐度较高;还原环境;古地温梯度高, 为3. 830 ℃/ 100 m 等流体特征。研究结果为该坳陷油气成因及识别未熟—低熟油成油物理化学条件等提供了信息。