极区冰基拖曳式海洋剖面浮标系统低功耗设计与实现

针对极区冰基拖曳式海洋剖面浮标长期稳定获取极区水文和气象数据的工作需求,进行了浮标系统的低功耗方案设计。该方案基于超低功耗51系列微处理器,根据最低功耗工作模式与最短工作时间原则,采用高效的电源管理机制对浮标系统各个部分的能量消耗进行合理的分配与管理,并应用了Argos卫星通讯模块ARGOS-3 PMT-RFM的BPSK调制低速数据传输模式,可有效降低浮标系统的整体能耗。该浮标在北极冰站上长达1年的运行情况表明该系统工作稳定,所采用的低功耗能量管理方案实现了浮标系统长期连续观测的需求。该浮标的成功试验和推广应用有助于极地研究人员更准确地分析海冰变化过程。     

周期性饥饿再投喂对曼氏无针乌贼(Sepiella japonica)幼体生长、体组成及氨基酸和脂肪酸的影响

采用持续投喂(对照组C)和周期性饥饿1d再投喂5d(S1F5)、周期性饥饿2d再投喂4d(S2F4)、周期性饥饿3d再投喂3d(S3F3)4种投喂策略,研究了周期性饥饿再投喂对曼氏无针乌贼(Sepiella japonica)幼体(10.16±0.25g)的生长、体组成、氨基酸和脂肪酸的影响。结果表明:S3F3处理组中体重增重率、胴体长增长率及成活率三个指标均分别显著低于对照组C(P0.05),而S1F5和S2F4处理组三个指标均与对照组C差异不显著(P0.05)。另外,随着周期性饥饿时间的延长,体组成水分含量呈显著上升趋势(P0.05),而粗蛋白和粗脂肪含量均呈显著下降趋势(P0.05),灰分含量变化不显著(P0.05)。三个处理组中氨基酸总量(T)、必需氨基酸总量(E)均与对照组C差异不显著(P0.05);EPA、DPA和DHA含量均与对照组C差异不显著(P0.05)。综合上述结果表明,S1F5和S2F4组的曼氏无针乌贼幼体均出现了完全补偿生长,并且对其营养组成没有影响,建议曼氏无针乌贼幼体的最佳投喂模式为周期性饥饿2d再投喂4d。     

8种石首鱼类线粒体基因组特征及分子系统进化分析

为探讨石首鱼科(Sciaenidae)鱼类分子系统进化关系,采用生物信息学方法分析了黑鳃梅童鱼(Collichthys niveatus)、棘头梅童鱼(C.lucidus)、大黄鱼(Larimichthys crocea)、小黄鱼(L.polyactis)、鮸鱼(Miichthys miiuy)、白姑鱼(Pennahia argentata)、黄姑鱼(Nibea albiflora)和皮氏叫姑鱼(Johnius belangerii)共8种石首鱼类线粒体基因组全序列的基本特征。结果显示,除皮氏叫姑鱼外,其余7种石首鱼类编码的37个基因排列顺序与脊椎动物线粒体基因组相同。基因组碱基分布存在不均衡现象,A+T含量高于G+C含量。线粒体基因组的基因变异位点分析结果表明,ND4和ND5基因可作为COI基因的辅助分子标记,应用于石首鱼类群体遗传学的研究中。黄鱼亚科5种鱼类13个蛋白质编码基因的Ka/Ks比值远低于1,显示出较强的纯化选择。皮氏叫姑鱼与其他石首鱼间的遗传距离均较大且亲缘关系较远,暗示叫姑鱼属或为石首鱼类中较为原始的类群。基于线粒体基因组全序列构建NJ系统树支持黄鱼亚科和白姑鱼亚科亲缘关系较近的形态学结论。而基于去除控制区后序列和13个蛋白质编码基因序列构建的系统树则表明两亚科鱼类间的差别在非编码区更为明显。     

泥蚶(Tegillarca granosa)重组铁蛋白富集重金属离子的特性及化学传感器的研究

利用泥蚶(Tegillarca granosa)铁蛋白原核表达工程菌获得的重组铁蛋白,通过圆二色光谱分析蛋白二级结构,扫描电镜和电感耦合等离子质谱研究重组铁蛋白富集Fe~(2+)、Mn~(2+)、Cd~(2+)、Cr~(3+)、Hg~(2+)、Pb~(2+)和As~(3+)等7种重金属离子的特性,同时探索利用重组铁蛋白修饰丝网印刷电极,设计和制备重组铁蛋白检测Pb~(2+)和Cd~(2+)浓度的电化学生物传感器。结果表明复性成功的铁蛋白多为完整的?-螺旋结构,而复性不成功的蛋白聚集体则多为无规卷曲。重组铁蛋白的直径和形态与富集的离子种类有关。泥蚶铁蛋白对单一金属离子Fe~(2+)和Mn~(2+)的富集凸显优势。对两种混合金属离子的富集大多表现为竞争关系。但重组铁蛋白对Hg~(2+)和As~(3+)混合组的富集量明显高于单一金属离子组的富集量,对Hg~(2+)和As~(3+)混合组的富集表现出协同促进作用。重组铁蛋白传感器对Pb~(2+)和Cd~(2+)溶液的最低检测限为10μg/L。     

二(甲基环戊二烯)钐氯化物合成和晶体结构研究

作者以 Sm Cl3 与 (CH3 Cp) Na反应分离得到了三价稀土有机配合物 [(CH3 Cp) 2 Sm Cl·THF]2 的单晶 ,X-射线四圆衍射测定 ,该配合物属正交晶系 ,Pbna空间群 ,晶胞参数 a=9.6 6 2 (2 ) ,b=16 .4 76 (9) ,c=2 0 .582 (9) ;α=β=γ=90°,Z=4。并分析比较 [(CH3 Cp) 2 Sm Cl· THF]2 与其他三价稀土一氯化物的结构特点     

Resistance of Lophelia pertusa to coverage by sediment and petroleum drill cuttings

In laboratory experiments, the cold-water coral Lophelia pertusa was exposed to settling particles. The effects of reef sediment, petroleum drill cuttings and a mix of both, on the development of anoxia at the coral surface were studied using O₂, pH and H₂S microsensors and by assessing coral polyp mortality. Due to the branching morphology of L. pertusa and the release of coral mucus, accumulation rates of settling material on coral branches were low. Microsensors detected H₂S production in only a few samples, and sulfate reduction rates of natural reef sediment slurries were low (<0.3 nmol S cm⁻³ d⁻¹). While the exposure to sediment clearly reduced the coral’s accessibility to oxygen, L. pertusa tolerated both partial low-oxygen and anoxic conditions without any visible detrimental short-term effect, such as tissue damage or death. However, complete burial of coral branches for >24 h in reef sediment resulted in suffocation.     

片状微囊藻(Microcystis panniformis)——中国微囊藻属的一个新记录种

目前全球范围内先后有50多种微囊藻被描述记载,国内最新研究报道有12种.根据采自太湖的野外藻类样品,确定了中国微囊藻属的一个新记录种——片状微囊藻(Microcystis panniformis),对其分类学的形态特征进行详细的描述,并对其和分类学上相近的属种Pannus以及微囊藻属的鱼害微囊藻(M.ichthyoblabe)、铜绿微囊藻(M.aeruginosa)和水华微囊藻(M.flos-aquae)等的区分进行讨论.     

南海西北次海盆的磁条带重追踪及洋中脊分段性

由于缺少有效钻孔资料,对于南海扩张的时间一直存在较大的疑问.在南海三大海盆中,西北次海盆面积最小、磁条带特征不明显,因此对其扩张年代的争议最大.最新采集的高密度(小于10 km测线间距)船测地磁资料清晰地显示了西北次海盆磁条带的存在.在OBS和多道地震资料的约束下,利用船测地磁资料,本文对西北次海盆的地壳年龄进行了重追踪.根据定量的比较,西北次海盆的主体扩张始于35.8 Ma(C16n,2n),在34.7 Ma(C15)时其西南部开始扩张,扩张最终同时终止于33.2 Ma(C13n),整体的全扩张速率在40~50 mm/a之间.这表明南海的扩张可能首先起源于西北次海盆,在其结束扩张后,东部次海盆才开始打开(约30 Ma).得益于数据精度和密度的提高,利用化极后的磁力异常以及反演的磁化强度可以对西北次海盆进行二级中脊段的划分.我们共划分出六个中脊段和一个明确的转换断层.中脊的分段性与OBS反演的地壳厚度的变化相一致.转换断层东侧,中脊主体分为四个中脊段,每个中脊段长度均在30 km左右.转换断层西侧,存在一个长约50 km的中脊段和一个不确切的中脊段.中脊段上磁化强度的变化幅值和中脊段长度在整体上成正比.每个中脊段中央的磁化强度弱于中脊段两端的磁化强度,这与扩张速率相近的大西洋中脊的磁化强度特征一致.     

Global scale annual and semi-annual variations of daytime NmF2 in the high solar activity years

The annual and semi-annual variations of the ionosphere are investigated in the present paper by using the daytime F2 layer peak electron concentration (NmF2) observed at a global ionosonde network with 104 stations. The main features are outlined as follows. (1) The annual variations are most pronounced at magnetic latitudes of 40–60° in both hemispheres, and usually manifest as winter anomalies; Below magnetic latitude of 40° as well as in the tropical region they are much weaker and winter anomalies that are not obvious. (2) The semi-annual variations, which are usually peak in March or April in most regions, are generally weak in the near-pole regions and strong in the far-pole regions of both hemispheres. (3) Compared with their annual components, the semi-annual variations in the tropical region are more significant.In order to explain the above results, we particularly analyze the global atomic/molecular ratio of [O/N2] at the F2 layer peak height by the MSIS90 model. The results show that the annual variation of [O/N2] is closely related with that of NmF2 prevailing in mid-latitudes and [O/N2] annual variation usually may lead to the winter anomalies of NmF2 occurring in the near-pole region. Moreover, NmF2 semi-annual variations appearing in the tropical region also have a close relationship with the variation of [O/N2]. On the other hand, the semi-annual variations of NmF2 in the far-pole region cannot be simply explained by that of [O/N2], but the variation of the solar zenith angle may also have a significant contribution.     

DETRITAL ZIRCON U-PB DATING OF MODERN RIVERS' DEPOSITS IN PAMIR,SOUTH TIAN SHAN AND THEIR CONVERGENCE ZONE

By dating detrital zircon U-Pb ages of deposition sequence in foreland basins, we can analyze the provenance of these zircons and further infer the tectonic history of the mountain belts. This is a new direction of the zircon U-Pb chronology. The precondition of using this method is that we have to have all-around understanding to the U-Pb ages of the rocks of the orogenic belts, while the varied topography, high altitude of the zircon U-Pb ages of the orogenic belts are very rare and uneven. This restricts the application of this method. Modern river deposits contain abundant geologic information of their provenances, so we can probe the zircon U-Pb ages of the geological bodies in the provenances by dating the detrital zircon U-Pb ages of modern rivers' deposits. We collected modern river deposits of 14 main rivers draining from Pamir, South Tian Shan and their convergence zone and conducted detrital zircon U-Pb dating. Combining with the massive bed rock zircon U-Pb ages of the magmatic rocks and the detrital zircon U-Pb ages of the modern fluvial deposit of other authors, we obtained the distribution characteristics of zircon U-Pb ages of different tectonic blocks of Pamir and South Tian Shan. Overlaying on the regional geological map, we pointed out the specific provenance geological bodies of different U-Pb age populations and speculated the existence of some new geological bodies. The results show that different tectonic blocks have different age peaks. The main age peaks of South Tian Shan are 270~289Ma and 428~449Ma, that of North Pamir are 205~224Ma and 448~477Ma, Central Pamir 36~40Ma, and South Pamir 80~82Ma and 102~106Ma. The Pamir syntaxis locates at the west end of the India-Eurasia collision zone. The northern boundary of the Pamir is the Main Pamir Thrust(MPT)and the Pamir Front Thrust(PFT). In the Cenozoic, because of the squeezing action of the India Plate, the Pamir thrust a lot toward the north and the internal terranes of the Pamir strongly uplifted. For the far-field effect of the India-Eurasia collision, the Tian Shan on the north margin of the Tarim Basin also uplifted intensely during this period. Extensive exhumation went along with these upliftings. The material of the exhumation was transported to the foreland basin by rivers, which formed the very thick Cenozoic deposition sequence. These age peaks can be used as characteristic ages to recognize these tectonic blocks. These results lay a solid foundation for tracing the convergence process of Pamir and South Tian Shan in Cenozoic with the help of detrital zircon U-Pb ages of sediments in the foreland basin.