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黄海桑沟湾水体及沉积物中微塑料污染特征研究 期刊论文 OAI收割
海洋环境科学, 2019, 卷号: 38, 期号: 2, 页码: 198-204
作者: 熊宽旭; 赵新月; 周倩; 付传城; 涂晨

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桑沟湾微塑料潮滩丰度空间分布 Sanggou bay microplastics tidal flats abundance spatial distribution In recent years,research on microplastics pollution in the marine environment has been increasing,but studies on microplastics in water bodies and sediments of the bay under the influence of high-intensity human activities are still rarely reported. In this study,the pollution characteristics of microplastics in the wayer and sediments of Sanggou bay were investigated in December 2017,after the harvest of large-scale aquaculture,with the aim to study the effects of aquaculture activities and hydrodynamics on pollution characteristics and spatial distribution of microplastics in the bay. The results showed that the types of microplastics in the water and sediments of Sanggou bay were mainly fibers,fragments,films,foams and particles. The microplastic abundances in the water and sediments were 1.8 ~ 31.2 N/L,31.2 ~ 1246.8 N/kg,respectively. The average particle sizes of microplastics in water and sediments were 0.51 0.20 mm and 1.54 1.02 mm,respectively. The results of spatial distribution of microplastics in Sanggou bay showed that the high abundance area mainly appears in the inshore waters,and the abundance of microplastics tends to decrease from the inner areas of estuary to the outshore areas. The heterogeneity of microplastic abundance and spatial distribution in Sanggou bay is mainly affected by human activities such as aquaculture,living and shipping,as well as hydrodynamics. In the future,fine sampling and analysis are needed to fully understand the temporal and spatial distribution of microplastics pollution in the bay areas.

烟台牟平海洋牧场季节性低氧对大型底栖动物群落的生态效应 期刊论文 OAI收割
生物多样性, 2019, 卷号: 27, 期号: 2, 页码: 200-210
作者: 李宝泉

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低氧群落结构群落恢复敏感种机会种 hypoxia community structure community recovery sensitive species opportunistic species Hypoxia is a common phenomenon in the world's oceans, especially in the shallow waters of coastal zones. Rates of hypoxia are increasing due to global climatic changes and anthropogenic activities. Hypoxia can cause mass mortality of marine animals and can have severe negative impacts on marine ecosystems. To better understand the effects of hypoxia on macrobenthic communities, a survey was carried out in the Muping Marine Ranch (Yantai) during June, August and September of 2016. Results showed that seasonal hypoxia led to changes in benthic community structure, especially in terms of species composition and dominant species. The dominant species were Polychaeta Lumbrinereis latreilli, Sternaspis scutata and Mollusca Endopleura lubrica in summer. The opportunistic species Lumbrinereis latreilli increased, whereas, sensitive species such as Leptomya minuta, Glycera chirori, Upogebia major, Pontocrates altamarimus, Eriopisella sechellensis decreased during the hypoxic period of August. Hypoxia also reduced biodiversity indices. The effect of hypoxia on abundance and biomass were not significant, mainly because of the increase in the opportunistic Lumbrinereis latreilli, which counteracted the decline in abundance and biomass of other species. Individual physiological tolerance to hypoxia was different among species. Lumbrinereis latreilli showed higher tolerance to hypoxia in dissolved oxygen (DO) = 1.0 mg/L compared to other species. Some sensitive species, such as Leptomya minuta, Upogebia major, Pontocrates altamarimus and Eriopisella sechellensis showed lower tolerance when DO < 2.5 mg/L. When DO increased to 2.5 mg/L, the macrobenthic community start to recover gradually. The recovery extent and time needed were closely related to the degree of seasonal hypoxia.

食用蔬菜能吸收和积累微塑料 期刊论文 OAI收割
科学通报, 2019, 卷号: 64, 期号: 9, 页码: 928-934
作者: 李连祯; 周倩; 尹娜; 涂晨; 骆永明

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微塑料生菜聚苯乙烯微球吸收积累健康风险 microplastics lettuce polystyrene microbeads uptake accumulation human health risk Microplastic (MP, 100 nm-5 mm) may present an attributable risk to ecosystem and human health, and its pollution has become a global environmental concern. Despite a wealth of information on the accumulation of MPs in aquatic species, there is no information on the uptake and accumulation of MPs by higher plants. Terrestrial edible plants are directly exposed to MPs when agricultural soil was applied with organic manure, sewage sludge as fertilizer or plastic mulching. In this paper, the uptake of two sizes of polystyrene (PS) microbeads (0.2 and 1.0 mum) and then their distribution and migration in an edible plant lettuce were firstly investigated based on laboratory experiments. We used fluorescent markers to track PS microbeads in plant tissues and found fluorescence to be a sensitive and reliable detection method. Sections from untreated control lettuce showed no autofluorescence. When roots were treated with fluorescently labeled PS microbeads, the microbeads could be identified by its fluorescence. Our main study investigated the uptake of 0.2 mum beads, as few luminescence signals were observed in lettuce roots for 1.0 mum beads in our experiment. We observed that 0.2 mum fluorescent microbeads were extracellularly trapped in the root cap mucilage (which is a highly hydrated polysaccharide) and a dark green tip (which was typical of lettuce roots exposed to label PS beads) was usually visible to the naked eye. Confocal images revealed that the PS luminescence signals were mainly located in the vascular system and on the cell walls of the cortex tissue of the roots, indicated that the beads passed through the intercellular space via the apoplastic transport system. Once inside the central cylinder, the 0.2 mum PS beads were transferred from the roots to the stems and leaves via the vascular system following the transpiration stream. We also observed that the PS beads adhered to one another and self-assembled systematically into grape-like and (chain) string-like clusters in the intercellular space of the root and stem vascular tissue of lettuce plant. In contrast to the root and stem, PS beads were dispersed in the leaf tissue. Here, for the first time we provide evidence of the adherence, uptake, accumulation, and translocation of submicrometer MPs within an edible plant. Our findings highlight the previously underappreciated human exposure pathway to MPs through the consumption of contaminated crops and emphasize the need for new management strategies to control the release of MPs waste products into the terrestrial environment. Ultimately, the potential impacts of low range sized MPs on food safety of crop plants and human health need to be urgently considered.

Spring constant regulate selectin-ligand bond dissociation 会议论文 OAI收割
第五届中美生物医学工程暨海内外生物力学学术研讨会, 中国北京/Beijing, China, 2013-08-01
作者: Zhang Y(章燕); Long M(龙勉); Lv SQ(吕守芹); Sun GY(孙淦云)

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dissociation regulate selectin constant formation further increased stiffness lifetime ligand binding assay Probe force kinetics mainly reverse values well found

Research on the key technology of ATP system for free space optical communication (EI CONFERENCE) 会议论文 OAI收割
31st Chinese Control Conference, CCC 2012, July 25, 2012 - July 27, 2012, Hefei, China
Meng H.; Liu X.; Zhang B.

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Free space optical communication is the bidirectional transmission technology that puts to use the laser beam as a carrier in space. Free space optical communication is generally used in the severe space environment. It is the mainly problem that the narrow beam of laser beam is high-precision aimed. and it is became very important that the technology of ATP is researched. Performance of the ATP system directly affects the performance of the quality of the free space optical communication. So research of the ATP is the key technology in FSO and this technology is discussed and analysed in the article. 2012 Chinese Assoc of Automati.

Precision analysis of simulation systems with hardware-in-loop caused by performance of three-Axis virtual flight motion simulator (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Manufacturing Science and Technology, ICMST 2011, September 16, 2011 - September 18, 2011, Singapore, Singapore
Wang T.; Zhu M.-C.; Yin S.-L.; Jia H.-G.

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Simulation systems with hardware-in-loop are composed by three-Axis virtual flight motion simulator simulation computer load torque simulator and visual simulation systems. Three-Axis Virtual Flight Motion Simulator are used to simulate the attitude of missile in simulation system with hardware-in-loop so its performance influenced the result of simulation directly. This paper mainly analyzed the factors which influenced the performance of a three-Axis virtual flight motion simulator which we are used now in the lab then analyzed the entire simulation system's error caused by these factors through numerical simulation method. By analysis we can see that bandwidth is the main factor influenced the precision of simulation systems with hardware-in-loop mechanical device installation error and measurement error may also cause some errors of the systems at the same time.

The load analysis of chisel-edge ruling tool for diffraction gratings (EI CONFERENCE) 会议论文 OAI收割
2012 International Applied Mechanics, Mechatronics Automation Symposium, IAMMAS 2012, September 7, 2012 - September 9, 2012, Shenyang, Liaoning, China
作者: zhang f.; zhang f.

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The process of wear design on chisel-edge ruling tool of diffraction gratings is very complex because of following two reasons that one is the load distribution on minute edge area when grating ruling and the other is the anisotropic character of natural diamond. The former is the first step when wear design on chisel-edge ruling tool of diffraction grating In order to predicate the load distribution on minute edge area of tool this paper simulated the load distribution on minute edge area of tool by software when ruling on Aluminum-1100 with tabular data format flow stress and Aluminum-1100 with Power law flow stress respectively and through comparative analysis determined the approximate load distribution on minute edge area of chisel-edge ruling tool that the high load mainly focused on the edge area close to the tip of ruling tool and amount to 200MPa while about to 100MPa on the face of tool. (2012) Trans Tech Publications Switzerland.

Physical layer design for free space optical communication (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Control Engineering and Communication Technology, ICCECT 2012, December 7, 2012 - December 9, 2012, Shenyang, Liaoning, China
作者: Wang H.; Zhang Q.; Guo J.; Guo J.; Wang H.

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A small size Free Space Optical Communication System is introduced including the hardware and the hardware specified physical layer protocol. In detail the rapid synchronization method to reduce the handshake bandwidth requirement is demonstrated. The hardware of the system includes the laser driver system the signal amplifying and shaping system the data interface system. The hardware specified physical layer protocol is used to interface the outer data serialize and deserialize the data stream check transmission errors and schedule the data transmission. The overall system is a FIFO-like system and the user can use it as if he's operating a FIFO. The system is designed mainly for terrestrial FSO link whose signal channel is the atmosphere. Due to the complex composition and activity of the atmosphere this signal channel brings in great influence on the transmitting laser in it for example the absorption and scattering of the atmosphere molecules and aerosols the scintillation of received laser power caused by the turbulence of the atmosphere all of which results in a much higher Bit Error Rate (BER) of the communication system than wired communication systems leading to frequent resynchronization. In our system the sampling clock is generated locally using multi-phase sampling technique rather than PLLbased clock recovery which helps to rapid synchronization. 2012 IEEE.

Research Progress of a New Type of potential anti-cancer drugs:ent-kaurane diterpenoids 期刊论文 OAI收割
中国化学会第9届天然有机化学学术会议论文集, 2012, 页码: 1
普建新

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potential:9813 Progress:1771 Research:638 drugs:325 cancer:183 family:19 throughout:18 interesting:17 years:15 genus:14 Labiatae:13 found:12 diterpenoid:12 morethan:12 world:10 literature:9 isolated:7 research:7 different:3 mainly:3

Time correlations in compressible isotropic turbulence 会议论文 OAI收割
23rd International Congress of Theoretical and Applied Mechanics, 中国北京/Beijing, China, 2012-08-19
作者: Li D; He GW(何国威); Zhang X(张星)

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compressible turbulence Time isotropic dilatational rescaling energy observed latter single found while mainly model without source well