江苏如东近海绿潮藻分子检测与类群演替分析

2007 年以来, 中国青岛、连云港、如东等黄海沿海连续4 年爆发绿潮现象, 尤其2008 年青岛爆发了世界最大规模绿潮, 造成了严重的生态危害. 2009 年, 我们对江苏省如东海域绿潮藻进行了调查和监测, 选取紫菜养殖架和防波堤坝上的11 个固着样品以及海区15 个漂浮样品, 对其ITS及5.8S rDNA 和叶绿体rbcL 基因序列进行了分子系统发育和类群演替分析. 结果显示, 如东沿岸堤坝和紫菜养殖筏架具有大量固着生长的浒苔类绿潮藻, 其海区漂浮绿潮藻团出现时间也最早,并逐渐北移; ITS 序列分析将如东样品聚为5 个类群, 即Ulva compressa 类群(6 个样品)、Ulva linza-procera-prolifera (LPP)复合体类群(12 个样品)、Ulva flexuosa 类群(3 个样品)、Blidingia sp.类群(3 个样品)以及Urospora spp.类群(2 个样品), 而rbcL 序列较为保守, 26 个样品只聚为4 个类群.DNA 序列分析表明, 如东海区漂浮与固着绿潮藻类群构成相同, 亲缘关系较近, 漂浮绿潮藻优势类群先后出现次序为: U. compressa, U. flexuosa 及LPP, 最终漂浮种与2008 年黄海绿潮优势种的ITS 序列完全相同. 本研究为今后黄海绿潮溯源及其预测防控奠定了重要基础.     

垂直旋转圆盘边缘液体滑移率及液柱形态

旋转圆盘表面液体与壁面之间存在切向相对滑移,液体的转速并不等于圆盘转速.利用高速摄影拍摄圆盘边缘液体形态,用软件Image J测量了液体的滑移率及液体头液滴与液柱的直径比.分析发现,垂直旋转圆盘不同区域的液体滑移率不同,随转速增加,各区域滑移率趋向相同,为10％～13％.圆盘表面的波动、边缘液体的形态会影响液体滑移率的...     

An Agent-based Adaptive Mechanism for Efficient Job Scheduling in Open and Large-scale Environments

Agent-based scheduling refers to applying intelligent agents to autonomously allocate resources to jobs.Decentralized agent-based scheduling approaches have ach...     

白腐菌对焦化废水中吲哚的降解及其机理

选用白腐菌BP降解吲哚,研究了白腐菌在不同培养基中对两种浓度吲哚的降解过程和机理,以及吲哚的降解与白腐菌漆酶酶活、生物量、培养基pH值的关系.结果显示不同培养基中白腐菌可去除99%以上的吲哚;吲哚去除率与白腐菌漆酶活率具有较好的相关性,白腐菌漆酶活率达到最高时,可去除97%以上的吲哚;高浓度吲哚会抑制白腐菌的生长,同时也激发了白腐菌漆酶的产生,秸秆滤出液能促进白腐菌的生长和漆酶活力的增长;白腐菌BP最适pH值为6~7,pH值在5~8之间对吲哚都具有较强的降解能力;在HPLC谱图3~6 min之间出现的新物质可能有氧化吲哚和靛红.     

基于Unity3D的水下机器人半实物仿真系统

基于Unity3D研制了一种由地面控制终端、机器人本体和三维仿真系统3部分组成的水下机器人半实物仿真系统,为水下机器人开发过程中的性能测试、控制算法分析和人员操作培训提供了仿真和测试平台。该系统采用同一地面控制终端作为三维仿真系统和机器人控制系统的统一指令输入源,以实现虚拟对象和机器人本体的同步工作,可对系统进行实时监测、调参。采用多目视觉技术对机器人位置采集,对传感器数据进行卡尔曼滤波处理。机器人运动仿真试验结果表明,机器人实际运动路径和仿真规划路径基本相同,该系统动态响应性和控制系统同步性较好。     

玛南斜坡下乌尔禾组砾岩储层特征及主控因素

准噶尔盆地玛湖凹陷南斜坡二叠系下乌尔禾组具有良好的勘探前景,为明确该区储层特征及主控因素,通过岩芯观察、铸体薄片、扫描电镜及储层物性等手段,对二叠系下乌尔禾组砾岩储层特征及主控因素进行了研究.结果表明,下乌尔禾组储层岩石类型主要为岩屑砂岩,胶结类型以泥质、沸石胶结为主,结构及成分成熟度较低.储层储集空间类型多样,以剩余...     

The start-up of biohydrogen-producing process by bioaugmentation in the EGSB reactor

Expanded granular sludge bed (EGSB) reactor and bioaugmentation were employed to investigate biohydrogen production with molasses wastewater. The start-up experiments consisted of two stages. In the first stage (0～24d) seeded with activated sludge, the butyric acid type-fermentation formed when the initial expanding rate, organic loading rate (OLR), the initial redox potential (ORP) and hydraulic retention time (HRT) were 10%, 10.0 kg COD/(m3·d), - 215 mV and 6.7 h, respectively. At the beginning of the second stage on day 25, the novel hydrogen-producing fermentative bacterial strain B49 (AF481148 in EMBL) were inoculated into the reactor under the condition of OLR 16. 0 kg COD/(m3·d), ORP and HRT about - 139 mV and 6.7 h, respectively, and then the reaction system transformed to ethanol-type fermentation gradually with the increase in OLR. When OLR, ORP and HRT were about 94.3 kg COD/(m3·d), -250 mV and 1.7 h, respectively, the system achieved the maximum hydrogen-producing rate of 282.6 mL H2/L reactor· h and hydrogen percentage of 51%～53% in the biogas.     

融合多源先验信息的舰船备件可靠性评估

舰船工作环境常导致备件的实际可靠性规律与设计参数不一致。在实际使用消耗量较小的条件下,全面分析备件可靠性信息来源,通过定义似然权重系数,融合多源先验信息,建立指数型备件可靠性的贝叶斯评估方法。最后,通过仿真分析验证方法的合理性。结果表明,所提出的基于似然权重的先验信息融合方法可以较好地融合不同信息源的可靠性信息,估计方法具有较好的稳定性。     

Robust Chattering-Free Finite Time Attitude Tracking Control with Input Saturation

This paper addresses the attitude tracking control problem of a rigid spacecraft in the presence of the modeling uncertainty, external disturbance, and saturated control input by designing two robust attitude tracking controllers. The basic controller is formulated using an integral sliding mode surface which is continuous and provides an asymptotic convergence rate for the closed-loop system. In this case, only the external disturbance with the prior information is considered. Then, to provide a finite time convergence rate and further improve the robustness of the control system under the unknown system uncertainty containing both the modeling uncertainty and external disturbance,a novel integral terminal sliding mode surface(ITSMS) is designed and associated with the continuous adaptive control method. Besides, a command filter is utilized to deal with the immeasurability problem within the proposed ITSMS and an auxiliary system to counteract the input saturation problem. Digital simulations are presented to verify the effectiveness of the proposed controllers.