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Dynamics of nonstructural carbohydrates in seagrass Thalassia hemprichii and its response to shading

Acta Oceanologica Sinica 2013年第8期32卷 61-67页

作者： jiang zhijian HUANG Xiaoping ZHANG Jingping Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of Oceanology Chinese Academy of Sciences Tropical Marine Biological Research Station in Hainan Chinese Academy of Sciences

A field survey was performed to examine nonstructural carbohydrate （NSC） dynamics in seagrass Thalassia hemprichii at the Xincun Bay in southern China. An indoor experiment to investigate the response of NSC in T. hemprichiito shade was conducted. Belowground tissue of T. hemprichiiwas the dominant site of NSC reserves, and soluble sugar was the primary storage compound. The starch content of belowground tissue was lower in high intertidal areas than in low intertidal areas, indicating that the longer air exposure in high intertidal areas resulted in less NSC synthesis and less accumulation of NSC in T. hemprichii. The lowest level of soluble sugar and its proportion to NSC in belowground tissue were observed near the cage culture area, where the nutrient concentration in water and sediment was the highest; while the highest level of that was observed near the coastal shrimp farm, where salinity was the lowest. Soluble sugar in belowground tis- sue showed the following trend： summer〉spring〉winter〉autumn. This corresponded to seasonal changes in the intensity of light. Leaf sugar accumulated during the autumn-winter period, providing a carbon and energy source for flower bud formation and seed germination. Short-term shading decreased NSC accumu- lation. Collectively, these results suggest that nutrient enrichment, freshwater discharge and exposure to air affect NSC dynamics in T. hemprichii. Light intensity, flower bud formation, and seed germination were all found to induce seasonal variations in NSC in T. hemprichii.

关键词： Thalassia hemprichii nonstructural carbohydrates Xincun Bay dynamics shade

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Adsorption Performance of Sliding Wall-Climbing Robot

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Chinese Journal of Mechanical Engineering 2010年第6期23卷 733-741页

作者： LI Jun GAO Xueshan FAN Ningjun LI Kejie jiang Zhihong jiang zhijian School of Mechatronical Engineering Beijing Institute of Technology Beijing 100081 China School of Electric and Information Engineering Beijing University of Civil Engineering and Architecture Beo＇ing 100044 China

Sliding wall-climbing robot （SWCR） is applied worldwide for its continuous motion, however, considerable air leakage causes two problems： great power consumption and big noise, and they constraint the robot＇s comprehensive performance. So far, effective theoretical model is still lacked to solve the problems. The concept of SWCR＇s adsorption performance is presented, and the techniques of improving utilization rate of given adsorption force and utilization rate of power are studied respectively to improve SWCR＇s adsorption performance. The effect of locomotion mechanism selection and seal＇s pressure allocation upon utilization rate of given adsorption force is discussed, and the theoretical way for relevant parameters optimization are provided. The directions for improving utilization rate of power are pointed out based on the detail analysis results of suction system＇s thermodynamics and hydrodynamics. On this condition, a design method for SWCR-specific impeller is presented, which shows how the impeller＇s key parameters impact its aerodynamic performance with the aid of computational fluid dynamics （CFD） simulations. The robot prototype, BIT Climber, is developed, and its functions such as mobility, adaptability on wall surface, payload, obstacle ability and wall surface inspection are tested. Through the experiments for the adhesion performance of the robot adsorption system on the normal wall surface, at the impeller＇s rated rotating speed, the total adsorption force can reach 237.2 N, the average effective negative pressure is 3.02 kPa and the design error is 3.8% only, which indicates a high efficiency. Furthermore, it is found that the robot suction system＇s static pressure efficiency reaches 84% and utilization rate of adsorption force 81% by the experiment. This thermodynamics model and SWCR-specific impeller design method can effectively improve SWCR＇s adsorption performance and expand this robot applicability on the various walls. A sliding wall-climbing

关键词： wall-climbing robot adsorption performance centrifugal impeller CFD simulation

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Relationship between nutrients and plankton biomass in the turbidity maximum zone of the Pearl River Estuary

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Journal of Environmental Sciences 2017年第7期29卷 72-84页

作者： Zhen Shi Jie Xu Xiaoping Huang Xia Zhang zhijian jiang Feng Ye Ximei Liang Key Laboratory of Tropical Marine Bio-Resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Key Laboratory of Marginal Sea Geology Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China College of Animal Science and Technology Jiangxi Agricultural UniversityNanchang 330045China

Nutrients,dissolved and particulate organic carbon and plankton（bacterio-,phyto-and zoo-）were compared in the turbidity maximum zone（TMZ） and adjacent areas（non-TMZ） in the Pearl River *** results showed that high levels of suspended substances had marked effect on dynamics of nutrients and plankton in the *** on the cluster analysis of total suspended solids（TSS） concentrations,all stations were divided into two groups,TMZ with average TSS of 171 mg/L and non-TMZ of 45 mg/*** substances adsorbed PO^（3-）_4 and dissolved organic carbon,resulting in higher particulate phosphorus and organic carbon（POC）and lower PO^（3-）_4 and DOC in the TMZ,compared to the ***,suspended substances had limited effect on nitrogenous *** growth was light-limited due to high concentrations of suspended substances in the TMZ and a peak of phytoplankton abundance appeared in the *** contrast,the highest bacterial abundance occurred in the TMZ,which was likely partly responsible for low DOC *** peaks of zooplankton abundance observed in the TMZ and non-TMZ in the Pearl River estuary were primarily supported by bacteria and phytoplankton,*** finding implied that high levels of suspended solids in the TMZ affect the trophic balance.

关键词： Nutrient Plankton Turbidity maximum zone Pearl River estuary

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Effects of seagrass leaf litter decomposition on sediment organic carbon composition and the key transformation processes

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Science China Earth Sciences 2017年第12期60卷 2108-2117页

作者： LIU SongLin jiang zhijian DENG YiQin WU YunChao ZHAO ChunYu ZHANG JingPing SHEN Yuan HUANG XiaoPing Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences South China Sea Fisheries Research Institute Chinese Academy of Fishery Sciences

Seagrass leaf litters are an important source of sediment organic carbon(SOC). However, the mechanisms of seagrass leaf litter decomposition influencing SOC composition and the key transformation processes remain unknown. We performed a laboratory chamber experiment to compare the labile organic carbon(OC) composition and the enzyme activities governing SOC transformation between the seagrass group(seagrass leaf litter addition) and the control group. The results showed that the seagrass leaf litter decomposition significantly elevated the salt-extractable carbon(SEC) content and the SEC/SOC. Additionally,the levels of invertase, polyphenol oxidase, and cellulase in the seagrass leaf litters addition group were generally higher than in the control group, which could elevate recalcitrant OC decomposition. Following 24 days incubation, addition of seagrass leaf litter increased the amount of CO_2 released, but decreased the SOC content. Therefore, seagrass leaf litter decomposition leached abundant dissolved OC, which enhanced the activity and transformation of SOC.

关键词： Seagrass leaf litter Sediment organic carbon Composition Enzyme activities

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Leaching of dissolved organic matter from seagrass leaf litter and its biogeochemical implications

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Acta Oceanologica Sinica 2018年第8期37卷 84-90页

作者： LIU Songlin jiang zhijian ZHOU Chenyuan WU Yunchao ARBI Iman ZHANG Jingping HUANG Xiaoping TREVATHAN-TACKETT Stacey M. Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Sciences Beijing 100049China School of Life and Environmental Sciences Centre for Integrative EcologyDeakin UniversityVictoria 3125Australia

Dissolved organic matter（DOM） represents a significant source of nutrients that supports the microbial-based food web in seagrass ecosystems. However, there is little information on how the various fractions of DOM from seagrass leaves contributed to the coastal biogeochemical cycles. To address this gap, we carried out a 30-day laboratory chamber experiment on tropical seagrasses Thalassia hemprichii and Enhalus acoroides. After 30 days of incubation, on average 22% carbon（C）, 70% nitrogen（N） and 38% phosphorus（P） of these two species of seagrass leaf litter was released. The average leached dissolved organic carbon（DOC）, dissolved organic nitrogen（DON） and dissolved organic phosphorus（DOP） of these two species of seagrass leaf litter accounted for 55%, 95% and 65% of the total C, N and P lost, respectively. In the absence of microbes, about 75% of the total amount of DOC, monosaccharides（MCHO）, DON and DOP were quickly released via leaching from both seagrass species in the first 9 days. Subsequently, little DOM was released during the remainder of the experiment. The leaching rates of DOC, DON and DOP were approximately 110, 40 and 0.70 μmol/（g·d）. Leaching rates of DOM were attributed to the nonstructural carbohydrates and other labile organic matter within the seagrass leaf. Thalassia hemprichii leached more DOC, DOP and MCHO than E. acoroides. In contrast, E. acoroides leached higher concentrations of DON than T. hemprichii, with the overall leachate also having a higher DON： DOP ratio. These results indicate that there is an overall higher amount of DOM leachate from T. hemprichii than that of E. acoroides that is available to the seagrass ecosystem. According to the logarithmic model for DOM release and the in situ leaf litter production（the Xincun Bay, South China Sea）, the seagrass leaf litter of these two seagrass species could release approximately 4×10~3 mol/d DOC, 1.4×10~3 mol/d DON and 25 mol/d DOP into the seawater. In addition to providing readily a

关键词： dissolved organic matter Thalassia hemprichii Enhalus acoroides leaf litter leaching

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海草床食物链有机碳传递过程的研究进展

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地球科学进展 2019年第5期34卷 480-487页

作者：黄小平江志坚中国科学院南海海洋研究所热带海洋生物资源与生态重点实验室广东广州510301 中国科学院大学北京100049

海草床是重要的近海生态系统,生产力极高,可为海洋动物提供良好的栖息地和丰富的有机碳食源;人类活动引起近岸海域的富营养化,可能会改变海草床有机碳源组成和性质,进而影响植食动物和次级消费者的摄食过程及其食物链能量传递效率,从而... 详细信息

海草床是重要的近海生态系统,生产力极高,可为海洋动物提供良好的栖息地和丰富的有机碳食源;人类活动引起近岸海域的富营养化,可能会改变海草床有机碳源组成和性质,进而影响植食动物和次级消费者的摄食过程及其食物链能量传递效率,从而影响海草床的生物资源产出功能。归纳总结了国内外海草床食物链碳传递过程各方面的研究进展,主要包括:①海草床有机碳源组成及食源贡献;②海草床初级消费者对有机碳源的摄食;③海草床食物网营养级结构及其能量传递;④富营养化对海草床有机碳源组分结构及其成分的影响;⑤海草床食物链能量传递效率对富营养化的响应。在此基础上,提出了未来的研究重点:①联合运用总有机物的稳定同位素比值法、脂肪酸标志法和特定化合物稳定同位素分析方法,加强定量研究海草床各有机碳源的贡献、食物网营养结构图谱、关键碳流途径及其季节性变化规律;探究关键消费者成体和幼体的有机碳源差异,弄清生长阶段的食性转化过程。②结合野外观测、原位围隔实验和室内模拟实验,深入探讨富营养化对海草床有机碳源组成(海草与附生藻类等)及其化学成分(营养质量和次生化合物)的影响,海草等初级生产者成分变化对植食动物和次级消费者摄食过程的影响,以及牧食食物链和碎屑食物链的组成和碳传递效率等的响应机制。

关键词：海草床食物链有机碳传递富营养化

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岩石细观结构量化试验研究

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岩石力学与工程学报 2007年第7期26卷 1313-1324页

作者：朱珍德渠文平蒋志坚河海大学岩土工程研究所江苏南京210098 中国有色金属工业公司昆明勘察设计研究院云南昆明650051

岩石是一种多尺度材料,以往的研究大多是在宏观尺度下进行的,由于岩石在外部荷载作用下的断裂乃至破坏是由于处于细观尺度的微裂隙的增长和贯通引起的,所以对处于细观尺度的微裂隙进行量化分析,对于了解和研究岩石的力学性质有一定的意... 详细信息

岩石是一种多尺度材料,以往的研究大多是在宏观尺度下进行的,由于岩石在外部荷载作用下的断裂乃至破坏是由于处于细观尺度的微裂隙的增长和贯通引起的,所以对处于细观尺度的微裂隙进行量化分析,对于了解和研究岩石的力学性质有一定的意义。首先,基于损伤理论建立一套岩石细观量化试验方法,利用扫描电镜对四川锦屏大理岩进行观测,得到大量岩石细观结构图片。基于数字图像处理理论,利用区域生长算法对图片进行处理,并编制相关程序实现图像增强和图像分割,从分割后的二值化图像中提取微裂隙的长度、方位角、宽度、面积和周长等细观信息。然后,利用统计学理论对获取到的微裂隙细观信息进行统计分析,得到各参数的统计规律,进一步利用Monte Carlo理论模拟岩石细观结构体积表征单元。最后,依据几何损伤理论得到岩石细观结构体积表征单元的初始损伤张量,将其引入到***的损伤理论中,模拟得到单轴压缩试验和常规三轴压缩试验的应力–应变关系,并与实际试验的结果进行比较。结果显示可以较准确模拟2种力学状态下的应力–应变关系。

关键词：岩石力学大理岩岩石细观结构量化扫描电镜图像处理损伤

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基于EEMD-CNN的滚动轴承故障诊断方法

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机械强度 2020年第5期42卷 1033-1038页

作者：李思琦蒋志坚北京建筑大学电信学院北京100044

为了提高滚动轴承故障诊断的准确性,提出了基于集合经验模态分解(Ensemble Empirical Mode Decomposition,EEMD)与卷积神经网络(Convolution Neural Networks,CNN)的故障诊断方法。首先使用EEMD对信号进行分解,并根据相关系数以及峭度... 详细信息

为了提高滚动轴承故障诊断的准确性,提出了基于集合经验模态分解(Ensemble Empirical Mode Decomposition,EEMD)与卷积神经网络(Convolution Neural Networks,CNN)的故障诊断方法。首先使用EEMD对信号进行分解,并根据相关系数以及峭度值选取适当的本征模态函数(Intrinsic Mode Function,IMF)进行信号重构。对重构信号进行一系列指标计算后使用卷积神经网络以及多种方法进行故障诊断。结果表明,所使用的方法能够有效地进行故障诊断,准确率可达96.7%,在实际中有着一定的应用意义。

关键词：集合经验模态分解卷积神经网络故障诊断机器学习

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感应电机调速系统新型滑动模解耦与自校正控制

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中国电机工程学报 1999年第1期19卷 1-5页

作者：吴捷姜智坚钱来华南理工大学电力学院

文章分析和设计了一类新型感应电机调速系统，整个系统分成内、外环。论文首先通过适当选择坐标框架，提出一个简明的感应电机数学模型，并以此为基础，在内环设计了一个滑动模转矩控制器，因而它不但可实现转矩和磁通的解耦控制，而且... 详细信息

文章分析和设计了一类新型感应电机调速系统，整个系统分成内、外环。论文首先通过适当选择坐标框架，提出一个简明的感应电机数学模型，并以此为基础，在内环设计了一个滑动模转矩控制器，因而它不但可实现转矩和磁通的解耦控制，而且对电机参数变化和外界干扰还具有较强的鲁棒性。外环的设计则引入自校正控制器——零极点配置控制器（含实时参数辨识）。仿真结果表明，整个系统在外环采用自校正控制后能进一步提高系统的鲁棒性和改善动态跟踪性能。

关键词：感应电机调速系统滑动模解耦自校正控制

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群感效应与信号分子在污泥颗粒化过程中的作用研究进展

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应用与环境生物学报 2016年第4期22卷 718-724页

作者：唐堂王硕蒋志坚李激江南大学环境与土木工程学院无锡214122 江苏省厌氧生物技术重点实验室无锡214122 江苏省高校水处理技术与材料协同创新中心苏州215009 国联环保能源集团有限公司无锡214122

好氧颗粒污泥具有良好的沉降性能和较好的污水处理效果等优点.本文综述好氧颗粒污泥的形成过程,重点分析在污泥颗粒化过程中群感效应和细胞信号分子的作用.研究发现,群感效应和细胞信号分子在污泥颗粒化过程中发挥着重要作用,群感效应... 详细信息

好氧颗粒污泥具有良好的沉降性能和较好的污水处理效果等优点.本文综述好氧颗粒污泥的形成过程,重点分析在污泥颗粒化过程中群感效应和细胞信号分子的作用.研究发现,群感效应和细胞信号分子在污泥颗粒化过程中发挥着重要作用,群感效应可以加快污泥胞外聚合物合成和提高微生物表面附着能力,信号分子可以促进微生物分泌胞外聚合物并影响生物膜的形成.举例说明信号分子中的c-di-GMP作为第二信使在污泥颗粒化过程中的重要作用,c-di-GMP可以将细菌从单细胞游走型转变为多细胞黏附型——生物膜状态.投加钙离子会促进能够分泌c-diGMP的菌群生长从而加快好氧颗粒污泥的形成,投加锰离子会减少好氧颗粒污泥中c-di-GMP的含量导致好氧颗粒污泥解体.最后进行前景展望,认为从群感效应和信号分子的角度去解析好氧颗粒污泥形成机理,可为确立好氧颗粒污泥形成机制奠定理论基础,对其进一步的工程化应用具有现实意义.

关键词：好氧颗粒污泥颗粒化群感效应信号分子

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