几种非营养无公害添加剂对大菱鲆的效应和机理研究

在基础饲料中分别添加0.04％低聚木糖、0.13％酵母细胞壁、0.08％胆汁酸和同量组合添加，形成5个处理组。采用随机区组试验设计，将体重151.3±15.2 g 的健康大菱鲆鱼165尾平均分配到5个处理组(A～E)中（每组3重复），经72天试验，进行了生长、水质、消化、免疫等试验和测定，结果如下： 组合组的生长效果和饲料利用率最好，酵母细胞壁或低聚木糖单独添加，表现出优良的促生长和饲料利用率；单独添加胆汁酸也有良好效果。4试验组（组合组、酵母细胞壁组、低聚木糖组、胆汁酸组）与对照组比较，增重率分别提高15.4％、13.9％、12.4％（p<0.05）和7.4％(P>0.05)，饲料系数分别降低6.9％、6.2％、5.4％（p<0.05）和3.8％(P>0.05)。 不同添加剂及组合对试验鱼所处水环境因子变化仅有小幅影响，统计差异不显著（p>0.05）。4试验组比对照组的水体氨氮含量分别提高4.0％、3.2％、3.0％和0.8％(P>0.05)，COD含量分别提高2.8％、-2.2％、-3.4％和0.8％(P>0.05)。根据试验结果，建议水环境因子（氨氮、磷酸盐、COD等）作为水产动物营养与饲料研究的主要衡量指标之一。 3种添加剂组合后达到提高生长大菱鲆非特异性免疫功能的最优效果，对补体C3和C4、细胞吞噬活力和SOD的提高作用尤为显著；酵母细胞壁单独添加对补体C3和细胞吞噬活力的作用更加显著；低聚木糖单独添加对补体C4和细胞吞噬活力的作用显著；单独添加胆汁酸提高免疫力的作用相对较弱。 4试验组比对照组的蛋白质消化酶活力在胃和前肠，分别提高20％和24％、17％和19％、16％和15％（p<0.05）、11％和3％(P>0.05)；脂肪消化酶活力在前肠和中肠，分别提高22％和19％、19％和17％（p<0.05）、7％和12％（p>0.05）、19％和18％（p<0.05）。 4试验组比对照组的蛋白质消化率分别提高了3.6％、2.9％、3.7％（p<0.05）和1.5％（p>0.05）；粪蛋白质排出量减少12.7％、7.1％、13.4％和2.4％（p>0.05）。说明，3种添加剂显著提高了生长大菱鲆蛋白质消化率，使粪蛋白质排出量不同程度降低，显示了试验使用添加剂的无公害效应。 权衡不同添加剂及其组合对大菱鲆生长期生长性能、饲料利用率、水生态因子、消化酶活力、非特异性免疫、蛋白质消化与粪蛋白质排出的综合影响，本研究从生态与环保角度得出：3种添加剂组合的效果最好，酵母细胞壁或低聚木糖单独添加表现出优良效果；单独添加胆汁酸也有良好作用。

根田鼠气味识别的性二型

以新鲜尿和粪作气味源,在行为选择箱中观察根田鼠的行为识别模式,结果表明:雌鼠对陌生同性尿、粪气味源行为识别的差异不显著,雄鼠对陌生同性尿、粪气味源的行为识别在多个指标上存在显著差异;根田鼠对陌生异性尿、粪的行为响应模式无明显差异;除嗅舔时间外,雌、雄鼠对粪气味的行为识别在其他指标上不存在明显差异;比较雌、雄鼠对尿刺激的行为识别发现,雄鼠对尿刺激的访问频次和反标记显著大于雌鼠,雌性嗅舔时间显著大于雄性,其他方面二者之间并无显著差异.因此,雌、雄性根田鼠对粪气味的行为识别模式不存在性别差异;对尿气味的行为识别模式存在性别差异.

中国南方热带地区田洋玛珥湖24万年以来的气候变化及湖泊演变

A continuous long (224m) and high-resolution core TY2 was recovered from paleo-maar-lake Tianyang, tropical South China. Based on the diatom records of the upper 130-m core, this paper focuses on exploring climate change and the lake evolution history in tropical South China during the past 240ka. The most typical and unique characteristics of the diatom assemblages is that, Aulacoseira granulata was dominant or absolutely dominant species (80-90%) during most parts of the 130-m core, while Cyclotella stelligera var. tenuis and Fragilaria construens var. venter were subdominant species in only limited parts of the lower and upper core, respectively. Time scale is always the biggest problem for the study of TY2 core, so although diatom is seldom used for establishing time scale, here we attempt this by correlating the diatom-reconstructed temperature sequence with the time scale of ODP core 806B from Equatorial Western Pacific. Verified by the few most reliable ages from TY2 core and the parallel core TYl, a rather reasonable and reliable time scale was established. 01S 7/6 falls at the depth of 100m (ca. 194kaBP), OIS 6/5 at 75m (ca. 132kaBP), OIS 5/4 at 46m (ca. 75kaBP), OIS 4-3 at 35m (ca. 60kaBP). Qualitative and quantitative environmental reconstructions are made on the basis of diatom assemblage ecotype and EDDI dataset. Correlation of diatom-reconstructed temperature and moisture changes of Core TY2 with pollen-reconstructed temperature and rainfall sequence of Core TYl proves that the results are quite consistent in most periods. Thus the reconstruction results from diatom are quite reliable, and probably have a much higher resolution than pollen results. Combined with lithological and magnetic susceptibility variations, the diatom analysis reveals that, the general climate in tropical South China during the past 240ka was warm and wet. On the time scale of glacial-interglacial, warm and wet, cool and dry are not always synchronous. It was relatively warm-wet during the penultimate interglacial, cool-dry during the penultimate glacial, warm-dry during the last interglacial, and cooler-drier during the last glacial. In contrast, on the time scale of subglacial-subinterglacial scales, warm and dry, cool and wet corresponds very obviously, showing very clear 21-23 ka precession cycle. Analysis also shows that, the water of Tianyang paleo-maar-lake was generally warm, turbulent, turbid, meso-trophic, slightly alkaline, low conductivity and fresh during the past 240 kaBP, with small variations in some parts. Tianyang paleolake experienced shallow to semi-deep lake in OIS7d, open shallow lake in OIS7c-OIS5b, shallow coastal lake in OIS5a-OIS4c, swamp in OIS4b, and then completely dried up in OIS3c. The lake evolution was mainly controlled by temperature and precipitation changes in tropical China. While temperature and precipitation changes were probably controlled by the migrations of monsoon rainband and the evaporation rate, which was in turn controlled by the evolution of East Asian monsoon. Therefore, when the summer monsoon was strongest the climate was warm-dry, when stronger the climate was warm-wet; when the winter monsoon was strongest the climate was cool-dry, stronger cool-wet. This mechanism caused the warm-dry sub interglacial and cool-wet subglacial climate in the tropical South China.

三类高强度悬式瓷绝缘子的成分特征和产品性能的关系

采用原子吸收光谱(AAS)、X射线衍射(XRD)、偏光显微镜(OH)和分析型透射电镜(TEM)等技术手段，对贵州产70kN和日本进口120kN、210kN三类瓷绝缘子的化学组成，矿物成分特征和产品性能的关系进行了研究。结果表明，三类产品的主化学成分为siO2、Al2O3。矿物相有刚玉、英来石、石英和长石。产品除含有偏光显微镜可分辨的晶体外，在电镜下还见有微米级以下的显微矿物。不同等级的产品，不但结晶相含量不同，晶体大小、分布状态各有特征。指出贵州产70kN产品应控制K20含量，并用部分工业氧化铝替代铝矾土，通过调整工艺提高结晶相的含量。