太湖表层沉积物多环芳烃的空间分布、来源及其风险

随着太湖流域社会与经济的发展,多环芳烃(PAHs)在各种环境介质中逐渐累积,污染日益严重,可能对太湖生态环境及周边人体健康构成威胁。为探究太湖沉积物PAHs的来源及生态风险,于2021年12月在太湖采集30个表层沉积物样品,利用气相色谱-质谱联用仪(GC-MS)检测样品中16种PAHs含量;利用受体模型和苯并[a]芘(BaP)毒性当量法进行来源解析及生态风险评估,并将各来源贡献与毒性当量浓度相结合,量化源风险。结果表明,太湖表层沉积物中16种PAHs总含量介于124~592 ng/g之间,平均值为294 ng/g,中值为279 ng/g;高环多环芳烃(HMW PAHs)为主要组分,占∑PAHs的67%。高含量区域位于竺山湾、梅梁湾、贡湖湾和西太湖,与国内外其他湖泊沉积物相比,太湖沉积物PAHs含量处于较低水平。源解析的结果表明,太湖表层沉积物中PAHs交通排放源贡献率为29.1%、煤炭燃烧源贡献率为26.7%、生物质燃烧源贡献率为28.7%、石油源贡献率为15.6%。生态风险评价结果表明,交通排放源、生物质燃烧源、煤炭燃烧源和石油源的BaP毒性当量含量(TEQ_BaP)均值分别为19.34、17.81、16.33和9.1 ng/g,均小于70 ng/g,几乎处于无风险水平。西太湖、贡湖湾和梅梁湾的部分区域ΣTEQ_BaP大于70 ng/g属于潜在风险区,具有一定潜在毒性。在后续的污染治理中应重点关注太湖西北部地区污染物的排放。本研究可为沉积物中PAHs污染的研究提供数据支撑,为地方政府精准、高效地管控PAHs污染提供理论依据。     

基于小波分析的海洋平台实时结构健康监测

由于海洋平台结构长期处于恶劣的海洋环境中,并受到各种载荷的交互作用,结构容易产生各种形式的损伤。因此,对海洋平台进行实时监测有着十分重要的现实意义。以单筒简易导管架平台为例,主要在结构损伤的判定和定位两方面对海洋平台的实时结构健康监测进行研究,结果表明通过对结构响应信号进行小波分析,小波变换系数和小波包能量分布可以很好地定义损伤识别指标。     

Long-term effects of di-octyl phthalate on the expression of immune-related genes in <Emphasis Type="Italic">Tegillarca granosa</Emphasis>

Di-octyl phthalate (DOP) is widely used as a plasticizer in the plastics industry. As a result, DOP is often found in marine water ecosystems where many species are exposed to it. Our objective was to evaluate the effect of long-term (14 d) DOP exposure (2.6, 7.8, or 31.2 mg/L) on the expression of immunerelated genes in Tegillarca granosa. The expression of small heat shock protein (sHSPs) and tissue inhibitor of metalloproteinase (TIMP) were highest in clams exposed to 31.2 mg/L DOP on days 7 and 14. The relative expression of Tg-ferritin, superoxide dismutase (SOD), and metallothionein (MT) increased initially then decreased as the concentration of DOP increased. The hemoglobin of T. granosa (Tg-HbI) exhibited two distinct expression patterns at two time points. Our results suggest that the immune response of T. granosa against DOP pollution varies depending on the dose. Additionally, we identified some immune-related genes that are promising candidates for biomarkers of DOP.     

Underwater Terrain Positioning Method Based on Least Squares Estimation for AUV

To achieve accurate positioning of autonomous underwater vehicles, an appropriate underwater terrain database storage format for underwater terrain-matching positioning is established using multi-beam data as underwater terrain-matching data. An underwater terrain interpolation error compensation method based on fractional Brownian motion is proposed for defects of normal terrain interpolation, and an underwater terrain-matching positioning method based on least squares estimation (LSE) is proposed for correlation analysis of topographic features. The Fisher method is introduced as a secondary criterion for pseudo localization appearing in a topographic features flat area, effectively reducing the impact of pseudo positioning points on matching accuracy and improving the positioning accuracy of terrain flat areas. Simulation experiments based on electronic chart and multi-beam sea trial data show that drift errors of an inertial navigation system can be corrected effectively using the proposed method. The positioning accuracy and practicality are high, satisfying the requirement of underwater accurate positioning.     

石河子地区1988年冬春小麦产量下降的气候原因

1987年～1988年度,石河子种植小麦53万亩,其中冬麦32.8万亩,春麦20.6万亩.平均单产248.35公斤,比1987年的251.5公斤降低了3.2公斤.造成今年冬春小麦减产的原因固然很多,但生长期不利的气象条件也是造成1988年小麦欠收的重要原因之一. 一、秋季降水过多,影响了冬麦适时播种和苗期生长发育石河子1987年秋季,前期温度较高,从表1看出,9月平均气温比多年同期平均偏     

载人潜水器发展现状及趋势

海洋蕴藏着国家经济发展和国防建设不可或缺的丰富的战略资源,世界各国不断加大在国际海域活动的力度,展开了空前的技术研究与竞赛。深海活动离不开高技术运载装备的支撑,以载人潜水器为代表的运载装备不仅对资源调查与科学研究做过杰出的贡献,而且在军事领域也产生过深远的影响。文中对国内外载人潜水器的发展现状进行了重点分析,对世界范围内重型深海载人潜水器及轻型中浅海载人潜水器的进展现状进行了全面调研,同时介绍了我国"蛟龙号"、"深海勇士号"等载人潜水器发展情况,也对世界范围内载人潜水器的技术性能和应用情况进行了分析对比,在此基础上,展望了载人潜水器的发展趋势,并讨论了潜水器装备的未来技术进展。     

一种智能水下机器人进行大范围海洋环境监测的方案与实验

采用智能水下机器人进行海洋环境的立体监测具有监测范围广,自主性强的特点。本文在探讨世界各国采用智能水下机器人进行海洋环境监测的情况的基础上,介绍了自主研发的智能水下机器人海洋大范围环境数据的自主采集系统,其主要优点是：相对于其他机器人,可实现“大范围” 海洋环境数据的采集;相对于固定式浮标,可实现海洋环境数据的“自主”采集。并给出了自主采集流程和软件分层递阶体系结构。在真实海域中,采用智能水下机器人,进行了国内首次大范围环境数据采集实航实验。实验结果表明采用智能水下机器人进行海洋环境的立体监测是切实可行的。     

Stability Analysis on Speed Control System of Autonomous Underwater Vehicle

The stability of the motion control system is one of the decisive factors of the control quality for Autonomous Underwater Vehicle (AUV).The divergence of control,which the unstable system may be brought about,is fatal to the operation of AUV.The stability analysis of the PD and S-surface speed controllers based on the Lyapunov' s direct method is proposed in this paper.After decoupling the six degree-of-freedom (DOF) motions of the AUV,the axial dynamic behavior is discussed and the condition is deduced,in which the parameters selection within stability domain can guarantee the system asymptotically stable.The experimental results in a tank and on the sea have successfully verified the algorithm reliability,which can be served as a good reference for analyzing other AUV nonlinear control systems.     

南移养殖仿刺参（StichopusjaponicusSelenka）铁蛋白基因的克隆及表达特征分析

采用cDNA文库、RACE、荧光定量PCR和Westernblot技术,克隆了南移养殖仿刺参铁蛋白基因的全长序列,并对其表达特征进行了研究。结果表明,南移养殖仿刺参铁蛋白cDNA全长1222bp,包括187bp的5’UTR;513bp的3’UTR和编码173个氨基酸残基的522bp的开放阅读框。诸如铁结合序列标签和铁调...