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21.
SUI Yanming WANG Senyang MOHSEN Mohamed ZHANG Longsheng SHEN Mengyan LIU Zhiquan NGUYEN Haidang ZHANG Shengmao LI Kaixing LV Linlan DONG Xuexing 《中国海洋大学学报(英文版)》2022,21(2):509-519
The presence of microplastics in aquatic ecosystems is of increasing global concern.Nano-sized plastics,in particular,can penetrate the cell membrane and cause biological death.Our study evaluated the combined impacts of several polystyrene mi-crospheres’sizes and nominal concentrations on the overall performance changes of Brachionus plicatilis.Experimental animals were exposed to three microplastic sizes(0.08,0.5 and 6μm)and five nominal concentrations(0,0.5,2,8,32μg mL?1)for 20 d.Our results showed that the toxicological effect of particle size on rotifers did not significantly depend on the nominal concentration.The interaction between the nominal concentration and size occurred only for body length and lorica width.Specifically,high nominal concentrations of microplastics that were close to nanometer size significantly impaired the overall vitality of rotifers,embodied in shortage of body type,delay in the arrival of maturity,reduction in the cumulative number of neonates,and the advance of the death process.In comparison,fair-sized size(0.5 and 6μm)displayed non-significant damage except for individual groups.Most notably,the net reproductive yield was only a third of what it was in the original environment,implying that there was not much fertility left.Besides,with the development of rotifers,the adverse effects of polystyrene microsphere drive had become more and more serious. 相似文献
22.
杨鹏 ZHAO Jian-xin NURIEL Perach UYSAL I Tongu? NGUYEN Ai Du ZHOU Renjie FENG Yue-xing 邬光辉 任战利 夏斌 《地质论评》2021,67(Z1):67z1254-67z1256
23.
A coastal acoustic tomography experiment in the Tokyo Bay 总被引：1，自引：0，他引：1
KANEKO Arat YAMAGUCHI Keisuke YAMAMOTO Tokuo GOHDA Noriaki ZHENG Hong SYAMSUDIN Fadli LIN Ju NGUYEN Hong-Quang MATSUYAMA Masaji HACHIYA Hiroyuki HASHIMOTO Noriaki 《海洋学报(英文版)》2005,24(1):86-94
Eight sets of coastal acoustic tomography (CAT) systems were deployed during November 29 to December 10, 2002 at the coasts on both sides of Tokyo Bay to measure tidal current structures at 15-rain interval.Sound transmission across the Tokyo Bay (between Yokohama and Chiba)was successfillly traced,even under severe interference from ship generated wakes and bubbles.Tidal current fields changing from northward to southward flow are well reconstructed by the inverse analysis of travel-time difference data for a period with the best sound transmission condition. It is suggested that the CAT is the most powerful tool to continuously map tidal current fields in the coastal seas with heavy shipping traffic and fisheries activity. 相似文献
24.
BUI Hoang B NGO Xuan Thanh Yungoo SONG Tetsumaru ITAYA Koshi YAGI KHUONG The Hung NGUYEN Tien Dung 《《地质学报》英文版》2016,90(5):1653-1663
Constraining the timing of fault zone formation is fundamentally important in terms of geotectonics to understand structural evolution and brittle fault processes.This paper presents the first authigenic illite K-Ar age data from fault gouge samples collected from the Red River Shear Zone at Lao Cai province,Vietnam.The fault gouge samples were separated into three grain-size fractions(0.1 μm,0.1-0.4 μm and 0.4-1.0 μm).The results show that the K-Ar age values decrease from coarser to finer grain fractions(24.1 to 19.2 Ma),suggesting enrichment in finer fraction of morerecently grown authigenic illites.The timing of the fault movement are the lower intercept ages at 0%detrital illite(19.2 ± 0.92 Ma and 19.4 ± 0.49 Ma).In combination with previous geochronological data,this result indicates that the metamorphism of the Day Nui Con Voi(DNCV) metamorphic complex took place before ca.26.8 Ma.At about 26.8 Ma-25 Ma,the fault strongly acted to cause the rapid exhumation of the rocks along the Red River-Ailoa Shan Fault Zone(RR-ASFZ).During brittle deformation,the DNCV slowly uplifted,implying weak movement of the fault.This brittle deformation might have lasted for ca.5 Ma. 相似文献
25.
越南东北部高平地区静足 (Tinh Túc) 钨锡矿床分布在银山-静足成矿带上,属于中国西南-越东北花岗岩相关的钨锡成矿带的一部分。花岗岩的锆石SIMS U-Pb测年结果为93.9±3.0Ma,地球化学分析结果显示出过铝质S型花岗岩的特点,高硅 (SiO2含量73.5%~74.6%),铝过饱和 (Al2O3含量14.21%~14.88%),高碱 (Na2O+K2O为6.64%~8.47%)、富钾贫钠 (K2O/Na2O>1),同时富集Rb、Th、U、Zr、Hf,亏损Ba、Nb、Sr、Ti、Eu,轻稀土相对富集,呈现明显的负Eu异常。同位素研究表明,样品的87Sr/86Sr初始比值为0.749±0.027,εNd(t) 为-10.71~-10.42。本文依据派洼花岗岩的地球化学特征,结合花岗岩的锆石U-Pb年代学、同位素分析结果,认为派洼花岗岩为燕山期后造山环境中形成的高度分异岩浆结晶的结果。通过与华南西南部矿床相关岩体比较,将静足派洼岩体归入个旧-大厂花岗岩带。并通过与缅甸境内腾冲-毛淡棉花岗岩带岩体特征对比并结合构造环境判别,提出个旧-大厂花岗岩带的形成可能受到太平洋构造域和特提斯构造域的双重影响,但以后者为主。 相似文献