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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
  |  收藏  |  浏览/下载:45/0  |  提交时间:2020/06/17
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
  |  收藏  |  浏览/下载:26/0  |  提交时间:2020/06/17
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.  
Gradient Structure-Induced Temperature Responsiveness in Styrene/Methyl Methacrylate Gradient Copolymers Micelles 期刊论文  OAI收割
macromolecular rapid communications, 2014, 卷号: 35, 期号: 3, 页码: 309-316
Zheng,Chao; Huang,Haiying; He,Tianbai
收藏  |  浏览/下载:27/0  |  提交时间:2015/10/15
In this work  micelles are formed by gradient copolymer of styrene and methyl methacrylate in acetone-water mixture and their temperature responsiveness is investigated in a narrow range near room temperature. Three different kinds of structural transitions could be induced by temperature: unimers to micelle transition  shrinkage/stretching of micelles  and morphological transition from spherical micelles to vesicles. In addition  a model analysis on the interface of gradient copolymer micelle is made to better understand these phenomena. It is found that both position and composition of the interface could alter in response to the change in temperature. According to the experiments and model analysis  it is proposed that temperature responsiveness might be an intrinsic and universal property of gradient copolymer micelles  which only originates from the gradient structure.  
Alternating stress dynamics analysis of harmonic gear flexible wheel (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Electrical Insulating Materials and Electrical Engineering, EIMEE 2012, May 25, 2012 - May 27, 2012, Shenyang, Liaoning, China
作者:  
Li M.
收藏  |  浏览/下载:53/0  |  提交时间:2013/03/25
This article is the study of alternating stress of flexible wheel in harmonic gear drive system. Firstly  then  Finally  according to elasticity theory to theoretically analyze flexible wheel stress  based on the basic principle of sub-structure modal synthesis method  based on the dynamics simulation  use the software of UG  to analyze the alternating stress simulation results of flexible wheel and compare theoretical results and simulation results to come conclusion. The results show that: altering stress simulation results of flexible wheel are coincident with theoretical simulation results  PATRAN and ADAMS to carry out co-simulation  have a deeper understand the stress change trend in the drive process of flexible wheel  lay a foundation for further carrying out dynamics simulation of harmonic gear drive system. (2012) Trans Tech Publications  Switzerland.  
Heterogeneous architecture-based software reliability estimation: Case study (EI CONFERENCE) 会议论文  OAI收割
3rd International Conference on Convergence and Hybrid Information Technology, ICCIT 2008, November 11, 2008 - November 13, 2008, Busan, Korea, Republic of
Wei Y.; Shen X.-H.
收藏  |  浏览/下载:34/0  |  提交时间:2013/03/25
With growing system complication  multiple structures are constructed in software  instead of single architecture style. As a result  the traditional architecture-based models that have considered only homogeneous software behaviors are not suitable to the complex system. In this paper a heterogeneous architecture-based model is presented. In order to verify the practicability  we apply the model to estimate the system reliability of the astronautics payload communication and monitoring system (APCMS). Multiple structures are constructed in the system  i.e.  sequence  parallel and fault-tolerance. The study results demonstrate that the model is accurate when compared to the actual reliability. Theoretical research must be applied on actual systems to understand their applicability and accuracy. 2008 IEEE.  
The spatial distribution patterns of biological soil crusts in the Gurbantunggut Desert, Northern Xinjiang, China 期刊论文  OAI收割
JOURNAL OF ARID ENVIRONMENTS, 2007, 卷号: 68, 期号: 4, 页码: 599-610
Zhang; Chen; Wang; Wang; Gu; Y. M.; J.; L.; X. Q.; Z. H.
收藏  |  浏览/下载:26/0  |  提交时间:2011/08/19
Fabrication and electron emission of carbon microtubes (EI CONFERENCE) 会议论文  OAI收割
Technical Digest of the 18th International Vacuum Nanoelectronics Conference, IVNC 2005, July 10, 2005 - July 14, 2005, Oxford, United kingdom
作者:  
Liu L.;  Liu L.;  Wang W.;  Wang W.
收藏  |  浏览/下载:46/0  |  提交时间:2013/03/25
Carbon nanotubes have been attracting attention because of their unique physical properties and their application potential for field emission cathode. Carbon nanotubes possess the following properties favorable for field emission material  such as a high aspect ratio and sharp tip  high chemical stability  high mechanical strength  stable at high temperature. Some research works on carbon nanotubes field emitter and field emission display have been reported. Here  a kind of carbon microtubes and its field emission properties are introduced. They have some different properties with carbon nanotubes  and the density is lower than carbon nanotubes bundles. These carbon microtubes are directly synthesized by liquidoid epitaxy method on silicon substrates at low temperature. The field emission properties of carbon microtubes are reported too. Carbon microtubes film is synthesized in liquid by electrolysis. The graphite plate is as anode  and n-silicon substrate with resistivity of 4-8 cm is as cathode. The electrolysis current is about 5-8mA/cm2  and applied voltage is 800-1500V. Temperatures of the methanol base solution is maintained at 60C in process of deposition of carbon microtubes. Carbon microtubes film is observed by scanning electron microscopy(SEM)  as shown in fig.1(a  b). The wall's thickness of carbon microtube is about 60nm. The diameter of carbon microtube is about 0.8 m. Raman spectrum of carbon microtubes film shows the two peaks at 1342and 1560cm-1. The field emission properties of carbon microtubes are measured in high vacuum chamber(10-5Pa). The emission area of carbon microtubes is 0.5cm 0.5cm. The threshold of field emission of the carbon microtubes film is about 3.6V/ m. Field emission property of carbon microtubes film is shown in fig.2. Another  when the electric field between anode and cathode is 10V/ m  the electric field distribution on single carbon microtube is also given after calculation according to electric field theory. Fig 3 shows that electric field distribution vertical section on the of single carbon microtube top with 2 m of highness. These results may help us to understand field emission properties of carbon microtubes. According to research results  it is found that liquidoid synthesis is simple method to produce carbon microtubes cold cathode material  and the carbon microtubes have better field emission properties. 2005 IEEE.  
Effects of Underfill's Filling Situation on the Reliability of Flip-chip Packages 会议论文  OAI收割
Fourth International Symposium on Electronic Packaging Technology, 北京/Beijing, China, 2001-8-8
作者:  
Liu S;  Zhao YP(赵亚溥);  Zhao YP(赵亚溥);  Liu S;  Liu S
收藏  |  浏览/下载:23/0  |  提交时间:2014/02/14