北京百花山若干冰缘现象的商榷

百花山是北京西山的第3高峰,海拔2046m。1991年10月12日,我们登上了山顶。事实证明,第四纪时期这里不存在任何冰川作用,但冰缘现象还能见到若干。     

循环载荷作用下损伤船体梁极限强度研究

为了研究循环载荷作用下扶强材初始损伤对其极限强度的影响,进行了14组扶强材的循环加载试验和分析。构造了考虑材料累积损伤完整、断筋和大变形的扶强材单元极限承载力计算公式,提出了相应循环载荷作用下损伤扶强材单元的端缩曲线表达式和船体梁极限强度计算的简化逐步破坏法。编制了循环载荷作用下船体梁损伤极限强度计算程序,进行了船体梁极限强度计算,并与有限元结果进行对比。研究结果表明：改进的损伤扶强材模型可较为准确地描述扶强材材料损伤的完整、断筋和大变形的极限承载力退化情况,扶强材腹板断裂的损伤相较初始大变形及材料累积损伤形式承载力下降程度更明显;所提出的循环载荷作用下损伤船体梁极限强度计算的简化逐步迭代方法,能定量地计算扶强材在不同类型损伤下的极限承载力退化程度,具有较高精度,方便易行,可应用于工程设计。     

电感耦合等离子体发射光谱法测定石膏矿样品中的三氧化硫

样品用稀盐酸处理,在酸性条件下石膏样品中的三氧化硫以硫酸根状态存在于待测溶液中,过滤除去酸不溶物。处理好的待测溶液可直接上等离子体发射光谱仪ICAP-6300(美国热电制造)上测定。方法的检出限为0.01%,采用本法测定国家标准物质GBW03109,GBW03109a,GBW03110,GBW03111a,结果表明标准样品测定的相对误差为-0.411%~0.274%,相对误差允许限为1.07%,能够满足分析质量要求。     

黄海沿岸若干港湾区海底沉积的抱粉组合及其意义

1984年5月, 阎嘉祺、杨梅忠在陕西铜川川口漆水河西侧黄土剖面前刚被推土机推过的松土中采集到一些哺乳动物化石, 紧接着就在推土机走过的西边黄土层中找到了尚未被推走的其他一些化石6这些化石多被黄土或钙质结核包裹。同年8月, 作者等一起到该化石点, 对化石层及其周围地质情况进行考察, 并在原化石点上发掘, 又采到一些化石标本。     

振幅属性在川中地区大安寨段中的应用——以J区块为例

川中地区大安寨段地层为典型的碳酸盐岩,主要储层为大-亚段。模型正演结果表明地层厚度与地震振幅强度存在一定关系。当地震波经过油气层时,其高频成分能量衰减较不合油气层时严重;谱分解技术利用最大熵谱方法,将地震数据变换到频率域,其地震振幅强度表征了油气分布情况。振幅属性在J区块大安寨段的应用效果明显,既可以定性预测大-亚段厚度,也能预测油气分布情况。     

Chromosomal localization of 5S rDNA in Chinese shrimp (Fenneropenaeus chinensis): a chromosome-specific marker for chromosome identification

Chinese shrimp (Fenneropenaeus chinensis) is an economically important aquaculture species in China. However, cytogenetic and genomic data is limited in the organism partly because the chromosomes are difficult to isolate and analyze. In this study, fluorescence in-situ hybridization (FISH) was used to identify the chromosomes of F. chinensis. The 5S ribosomal RNA gene (rDNA) of F. chinensis was isolated, cloned and then used as a hybridization probe. The results show that the 5S rDNA was located on one pair of homologous chromosomes in F. chinensis. In addition, triploid shrimp were used to evaluate the feasibility of chromosome identification using FISH and to validate the method. It was confirmed that 5S rDNA can be used as a chromosome-specific probe for chromosome identification in F. chinensis. The successful application of FISH in F. chinensis shows that chromosome-specific probes can be developed and this finding will facilitate further research on the chromosomes of penaeid shrimps.     

赤点石斑鱼增生性肾脏病的血液病理观察

血液病理学测定表明，患病赤点石斑鱼Epinephelusakaara组列的血红蛋白平均值约5.49g．（100ml）－1，颗粒白细胞平均值为48．09％，单核细胞平均值为2．82％，健康鱼组列的血红蛋白平均值为7.26g·（100ml）－1，颗粒白细胞平均值为31.33％，单核细胞平均值为0．11％，两组列间有明显差异（p＜0．05）。患病石斑鱼出现较多星个体小、膜薄易破、难着色的异形红细胞；颗粒白细胞的核分叶较多，病鱼表现出严重贫血症状。     

从泥河湾层花粉分析谈南沟冷期等问题

第四纪下限问题是地学的一个重要课题,故历来为人们所重视。分布在大同、阳原等盆地的泥河湾层,沉积厚,又有玄武岩穿插其间,剖面出露和接触关系清楚,含有丰富的动、植物化石,并有人类化石与石器,是罕见的第四纪典型剖面。近年来,我们对该区泥河湾层进行了花粉分析,现就其古植被、古气候和地层等方面的问题作一初步讨论。     

Rapid,sensitive detection of Vibrio anguillarum using loop-mediated isothermal amplification

Vibrio anguillarum is an important bacterial pathogen of aquatic organisms and a significant problem in aquatic farming.The rapid detection and identification of V.anguillarum,and other pathogens that infect marine organisms,is crucial to effective disease management.In this study,we developed a loop-mediated amplification (LAMP) assay to detect V.anguillarum in an hour in a single tube without the need for thermal cycling.Conserved regions of the metalloproteinase (empA) gene of V.anguillarum served as the targets for primer design.A fragment of the empA gene was amplified at 65°C in the presence of the primer mixture and Bst DNA polymerase.In the optimized LAMP assay,6.7 pg of V.anguillarum DNA could be detected.Six strains of V.anguillarum and 17 strains of non-V.anguillarum bacteria were used in this study to evaluate the species specificity of the primers.The six V.anguillarum strains gave a positive result in the LAMP assay.This method was also validated in V.anguillarum-infected fish.This LAMP method is more sensitive than PCR in the detection of V.anguillarum and shows good species specificity.The LAMP assay is therefore an effective method for the quick detection of V.anguillarum both in the laboratory and in the field.     

末次间冰期以来西宁市河谷沉积与环境

在西宁市区开展的钻探工作,获得了河谷平原区第四系的分布及沉积特征。通过对沉积厚度最大部位的2个钻孔岩芯的地层岩性、年代测试、孢粉组合及粒度分析等,探讨了西宁河谷平原区晚第四纪沉积与环境的关系。认为现今西宁市河谷平原内的主体沉积——低阶地沉积及上覆黄土堆积主要是末次间冰期旋回形成,在暖湿气候条件下沉积河流相砂砾石层,在干冷气候期接受风成黄土堆积,推测T3阶地形成于距今7.4万年前后气候由暖湿向干冷的过渡时期。