中国真囊水母属三个新种记述 水螅虫纲 花水母目 棒状水母科   总被引：5，自引：0，他引：5  

黄加祺 《海洋学报》1999,21(4):92-95

中国海域水螅虫纲(Hydrozoae),花水母目(Anthmedusae),棒状水母科(Corymorphidae)的真囊水母属(Euphysora)经研究有3个新种:褐色真囊水母(Euphysora brunnescentis sp.nov.)、刺胞真囊水母(Euphysora knides sp.nov.)和硬手真囊水母(Euphysora solidonema sp.nov.),对此予以详细的描述报道.模式标本保存于厦门大学海洋系.  相似文献   

Cold blobs in the subpolar North Atlantic: seasonality,spatial pattern,and driving mechanisms     

Shi  Jian  Wang  Jiaqi  Ren  Zixuan  Tang  Cong  Huang  Fei 《Ocean Dynamics》2023,73(5):267-278

Ocean Dynamics - This study analyzes the spatiotemporal features and physical drivers of cold blobs over the subpolar North Atlantic (NA) operating on interannual timescales based on ocean and...  相似文献   

太湖流域1991年特大洪涝成因与对策探讨   总被引：3，自引：3，他引：0  

陈家其 《湖泊科学》1992,4(2):52-59

受天地生相互作用影响,1991年大气环流异常,太湖流域出现了两度梅雨,雨期长、降水强度大。由于近数十年来,水域环境发生了变化,洪水出路不畅,6—7月间发生了特大洪涝,其特征是:降水逊于历史,水位超历史;成灾面积不及历史,经济损失远超历史。协调人地关系不善,加剧了这次洪涝灾害。因而,在统一规划下,协调好人地关系,是重要的减灾对策。  相似文献   

Geochemical characteristics and geological significance of Cretaceous phonotephrite from the Mid-Pacific Mountains     

Shuangshuang CHEN  Jiaqi LIU 《中国科学:地球科学(英文版)》2018,(6)

Systematic analyses were conducted including the petrographic features, major and trace elements, Sr and Nd isotopic compositions, and mineral structure and compositions of whole rocks. Mid-Pacific Mountain volcanic rocks are mainly phonotephrite with a porphyritic texture. Phenocrysts are mainly composed of Ca-rich plagioclase, clinopyroxene and nepheline.These volcanic rocks are significantly rich in large-ion lithophile and light rare earth elements, without obvious Eu anomalies(δEu=0.99–1.03), and with relatively enriched~(87) Sr/~(86) Sr(0.703829–0.704313) and~(143) Nd/~(144) Nd isotopic ratios(0.512857–0.512871), suggesting that they have similar but more enriched features than the OIB magmatic source. These volcanic rocks may originate from relatively deep magma source with the existence of spinel-garnet Iherzolites, and have undergone partial melting at a low degree of 1–3%. In addition, The residual Nb-Ta minerals(such as sphene, rutile, perovskite) may remain in the mantle source, and the magma components have undergone metasomatism by carbonate melt/fluid or alkali-rich fluid, causing high contents of incompatible elements and significant loss of Nb, Ta and Ti in these volcanic rocks. There are many similarities between the phonotephrites in the Mid-Pacific Mountain and the volcanic rocks in the Line Islands based on the tectonic settings and the geochemical characteristics. We thus speculate that Site 313 volcanic rocks in the Mid-Pacific Mountain is most likely to be a continuation of the Line Islands.  相似文献   

HN孔记录的淮北平原晚新生代8Ma以来气候及环境演化     

张磊  胡道功  秦小光  邓成龙  穆燕  李康康  刘嘉麒 《地质学报》2022,96(3):1091-1103

淮北平原地处中国南北方过渡的关键带,该地区晚新生代沉积的深入研究不仅能为中国南北方过渡带古气候环境演化提供重要信息,而且能为构建中国晚新生代从东到西完整气候环境格局提供东部关键地区记录.但目前该区域晚新生代长尺度的气候环境记录非常缺乏.本文利用淮北平原HN钻孔沉积物岩性、粒度、磁化率、色度等分析结果,结合磁性地层年代学...  相似文献   

西印度洋产纤维素酶细菌的筛选及酶学特性初步研究          下载免费PDF全文

吴旭东  童凡  夏钰华  黄仕新  黄家琪  徐长安  唐旭 《应用海洋学学报》2024,43(1):183-191

本研究从西印度洋表层沉积物中筛选获得1株高抗性、稳定性好的纤维素酶高产菌株XN149,通过形态学、革兰氏染色、生理生化鉴定以及16S rRNA基因序列分析对菌株进行分类鉴定,并研究了其酶学特性。结果表明,菌株XN149为漳州芽孢杆菌（Bacillus zhangzhouensis）,具有较高的产纤维素酶能力。酶学特性研究表明,该菌株所产纤维素酶的最适反应温度为65 ℃,最佳pH为6.0,该条件下发酵48 h后粗酶液酶活力为（60.19±0.31） U/mL。在30～60 ℃及pH为5.0～8.0时酶活性稳定性较高,Fe3+、Mn2+对该酶活性有一定的促进作用,Ba2+对其酶活性具有抑制作用。综上,漳州芽孢杆菌XN149是一株高产纤维素酶菌株,所产纤维素酶具有良好的耐热性和一定的酸碱耐受性,具有潜在的产业应用开发价值。  相似文献