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International Journal of Technology Management 2014年第2期 87-90页

作者： Xiao Huan-xin Wu Jun-yi Technical Center for Dangerous Goods Testing of Guang i Entry-Exit Inspection and Quarantine Bureau 536000BeihaiChina Technical Center for Dangerous Goods Testing of Guangxi Entry-Exit Inspection and Quarantine Bureau 536000BeihaiChina

Inductively coupled plasma optical emission spectrometric approach（1CP-OES） is used to determine the potassium content as principal component in pyrotechnic compositions used for fireworks and firecrackers. Element of potassium is conunonly found in potassium nitrate and potassium perchlorate in pyrotechnic compositions in fireworks and firecrackers. Statistical analysis shows that potassium nitrate content in pyrotechnics is between 10% to 60% and the potassium perchlorate content is between 20% to 70%,which counted in the content of potassium element is between 4% to 23%. Concept of this method： considering the weight of the sample is 400rag,constant volume is 1L and the concentration of potassium is between 10 mg/L to 90 mg/L in sample solution, the determination scope of the method for the potassium content would be between 1% to 23%.Further experiments proved that the fitting correlation coefficient of potassium calibration curve is 0.9997 or higher, recovery is 89.15%-100.23%.The allowable differential value is 0.4% between two single tests under repeatable conditions. This method can completely satisfy the requirements of the fireworks and firecrackers industry with high accuracy and good precision.

关键词： fireworks and firecrackers pyrotechnic compositions principal component potassium content determination inductively coupled plasma optical emission spectrometric approach ICP-OES.

Carbon Sources of Sediment and Epifaunal Food Sources in a Tropical Mangrove Forest in North Sulawesi, Indonesia

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Journal of Ocean University of China 2020年第5期19卷 1169-1176页

作者： WU Zhiqiang XIE Limei CHEN Bin DHAMAWAN I Wayan Eka SASTROSUWONDO Pramudji CHEN Shunyang RIANTA Pratiwi ERNAWATI Widyastuti CHEN Guangcheng College of Marine Life Sciences Ocean University of ChinaQingdao 266000China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China Research Center for Oceanography Indonesian Institute of SciencesJakarta 11048Indonesia Observation and Research Station of Coastal Wetland Ecosystem in Beibu Bay Ministry of Natural ResourcesBeihai 536015China

The stable isotope ratios of nitrogen(δ^(15)N) and carbon(δ^(13)C) were applied in this study to analyze sediment carbon sources and primary food sources of epifauna in an oceanic mangrove forest in tropical North Sulawesi, Indonesia. Proportional contribution of mangrove-derived carbon to the food sources was compared among epifauna belonging to different feeding guilds. The sediment in the mangrove site with a depleted δ^(13)C signature(-28.02‰± 0.24‰) mainly consists of mangrove-derived carbon. Analysis using Bayesian stable isotope mixing model in the R program shows that mangrove-derived carbon can dominate the food sources of a majority of the epifauna(11 out of the total 18 species), especially 2 sesarmid crabs Parasesarma semperi and Sesarma sp., crab Epixanthus dentatus, and snails Terebralia sulcata and Optediceros breviculum, which belong to various feeding guilds. Mangrove-derived carbon has a proportional contribution to the food sources of fiddle crab Tubuca coarctata and 3 littorinid snails(Littoraria spp.) close to that of suspended particulate organic matter. Three planktophagous bivalve species(Anadara antiquata, Anadara sp. and Callista erycina) were found to mainly feed on seagrass-derived materials. Mean proportional contributions of mangrove-derived carbon to the food sources were 50.15%, 59.60%, 46.20% and 27.58% for the carnivorous, omnivorous, phytophagous and planktophagous groups, respectively. The results suggest that mangrove-derived carbon can directly(via grazing plant tissues) or indirectly(via deposit feedings) make an important contribution to the food sources of epifauna in the oceanic mangrove forest where the allochthonous input of organic carbon is low.

关键词： epifauna stable isotope carbon nitrogen sediment feeding guilds

Prediction of the joint impacts of sea level rise and land development on distribution patterns of mangrove communities

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Forest Ecosystems 2023年第2期10卷 176-186页

作者： Shanshan Liang Wenjia Hu Peiqiang Wu Jianbu Wang Shangke Su Guangcheng Chen Jianguo Du Wenhua Liu Bin Chen Key Laboratory of Marine Ecological Conservation and Restoration Third Institute of OceanographyMinistry of Natural ResourcesXiamen361005China Institute of Marine Science Shantou UniversityShantou515063China First Institute of Oceanography Ministry of Natural ResourcesQingdao266061China Observation and Research Station of Coastal Wetland Ecosystem in Beibu Gulf Ministry of Natural ResourcesBeihai536015China

Mangrove distribution along shorelines shows distinct zonation patterns;thus,different communities may face various influences from sea level rise(SLR)and land ***,long-term change predictions are usually based only on the total extent of *** studies have revealed how SLR and land development such as agriculture,aquaculture,and urbanization jointly affect different intertidal mangrove *** study proposed a novel framework combining SLAMM(Sea Level Affecting Marshes Model)and the CLUE-S(Conversion of Land Use and its Effect at Small regional extent)model to assess the potential impacts on upper and lower intertidal mangrove *** in Guangxi,China,was selected as the study area and the potential impacts from the squeeze effect and mangrove expansion potential were *** established three scenarios combining SLR and land use patterns to predict mangrove coverage projections by *** results showed that,under a single SLR driver,the upper intertidal mangroves would be more adaptive to rapid SLR than the lower intertidal ***,under the combined influence of the two drivers,the upper intertidal mangroves would experience larger squeeze effects than the lower intertidal mangroves,with up to 80.5%of suitable habitat ***,the expansion potential of upper intertidal mangroves would be considerably more limited than that of lower intertidal *** length of the expandable habitat patch boundary of upper intertidal mangroves only reached 1.4–1.8 km,while that of the lower intertidal mangroves reached up to99.2–111.2 ***,we found that aquaculture ponds and cropland are the top two land development types that could occupy suitable habitat and restrict the mangrove expansion *** results highlight that timely improvement of land use policies to create available landward accommodation space for mangrove migration is essential to maintain the coverage and diversity of mangrove commun

关键词： Coastal development Climate change Mangrove communities Mangrove adaption Land use Sea level rise

Tracing surface seawater mixing and nutrient transport by^(222)Rn on the northern coast of Beibu Gulf,China

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海洋学报:英文版 2023年第8期42卷 87-98页

作者： Hao Wang Qiangqiang Zhong Fule Zhang Suiyuan Chen Hongyan Bao Jing Lin Dekun Huang Tao Yu College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China Observation and Research Station of Coastal Wetland Ecosystem in Beibu Gulf Ministry of Natural ResourcesBeihai 536015China State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361102China

The transport and diffusion of substances in seawater are limited by the mixing motion of water bodies,while the main forms of mixing in offshore water bodies are advection and eddy *** eddy diffusion process of water indicates the possible transport direction of dissolved ***,the complex environment in the coastal zone makes it difficult to quantitatively assess the water diffusion process.^(222)Rn is a useful tool to trace the diffusion process of water ***,studies on the^(222)Rn distribution and its behavior in the Beibu Gulf are *** this study,the activity distribution characteristics of^(222)Rn in surface seawater of the Guangxi shelf area of the Beibu Gulf were *** on the one-dimensional,steady-state model,the vorticity diffusion coefficient of^(222)Rn in the horizontal direction was calculated as(0.42−2.13)×10^(8) m^(2)/d,and the offshore fluxes of^(222)Rn under the influence of water mixing were calculated as 2.00×10^(12) Bq/***,the horizontal transport fluxes of silicate,phosphate,nitrite and nitrate were 6.28×10^(−3)mol/(m^(2)·d),0.10×10^(−3)mol/(m^(2)·d),0.20×10^(−3)mol/(m^(2)·d)and 4.15×10^(−3)mol/(m^(2)·d),*** results indicate that the study of eddy current diffusion in offshore marine water facilitates a deeper understanding of the water mixing process and nutrient transport and migration.

关键词： ^(222)Rn water mixing nutrients vorticity diffusion coefficient horizontal transport flux

Interannual variations in salt flux at 80°E section of the equatorial Indian Ocean

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中国科学:地球科学英文版 2023年第9期66卷 2142-2161页

作者： Cuncun XIE Ruibin DING Jiliang XUAN Daji HUANG State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Guangxi Key Laboratory of Beibu Gulf Marine Resources Environment and Sustainable DevelopmentFourth Institute of OceanographyMinistry of Natural ResourcesBeihai 536015China Institute of Polar and Ocean Technology Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

The interannual variations in salt flux on the 80°E section in the equatorial Indian Ocean were explored based on the ORAS5 data,which was quite consistent with the observational data among the four available reanalysis *** results indicated that the area with significant interannual variations in salt flux coincided with that of significant climatological mean salt flux in general and was mainly located in the upper 150 m ***,three important areas were identified in the north-south direction,i.e.,(1)the Equatorial Indian Ocean Area(EIOA,3°S–3°N),where the mean salt flux was eastward with the largest value on the section and associated with the most significant interannual variations mainly modulated by the Wyrtki Jets and the Equatorial Undercurrent;(2)the South Equatorial Indian Ocean Area(SEIOA,3°S–6°S),where the mean salt flux changed in the vertical direction from strong eastward flux in the upper layer to weak westward flux in the subsurface layer and associated with significant interannual variations in the upper 100 m layer,which was affected by the South Equatorial Countercurrent;and(3)the North Equatorial Indian Ocean Area(NEIOA,3°N–6°N),where the mean salt flux changed in the north-south direction from strong westward flux to the north of 5°N to weak eastward flux in the south and associated with relatively significant interannual variations,which was mainly influenced by the South Sri Lanka Coastal *** leading interannual variation modes were revealed by the empirical orthogonal function *** first mode accounted for 39%of the total variance and had four significant spatial antinodes;two of those in-phase antinodes were located at SEIOA and upper 75 m of EIOA,and the other two opposite in-phase antinodes were located at NEIOA and below 75 m of *** second mode accounted for 17%of the total variance having four antinodes with two dominant out-of-phase antinodes located at the subsurface of EIOA and ***

关键词： Salt flux Interannual variation 80°E section Equatorial Indian Ocean Current

Software-Defined Space-Air-Ground Integrated Network Architecture with the Multi-Layer Satellite Backbone Network

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Computers, Materials & Continua 2020年第7期64卷 527-540页

作者： Chao Guo Cheng Gong Juan Guo Zhanzhen Wei Yanyan Han Sher Zaman Khan Department of Electronics and Communication Engineering Beijing Electronics Science and Technology InstituteBeijing100070China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Vocational and Technical College of Guilin University of Electronic Technology Beihai536000China Institute of Business Administration Gomal UniversityDera Ismail Khan29220Pakistan

Under the background of the rapid development of ground mobile communication,the advantages of high coverage,survivability,and flexibility of satellite communication provide air support to the construction of space information *** to the requirements of the future space information communication,a software-defined Space-Air-Ground Integrated network architecture was *** consisted of layered structure satellite backbone network,deep space communication network,the stratosphere communication network and the ground *** Space-Air-Ground Integrated network was supported by the satellite backbone *** provided data relay for the missions such as deep space exploration and controlled the deep-space spacecraft when *** addition,it safeguarded the anti-destructibility of stratospheric communication and assisted the stratosphere to supplement ground network *** this paper,algorithm requirements of the congestion control and routing of satellite backbone protocols for heterogeneous users’services were *** algorithm requirements of distinguishing different service objects for the deep space communication and stratospheric communication network protocols were *** the realistic demand for the dynamic coverage of the satellite backbone network and node cost,the multi-layer satellite backbone network architecture was *** this basis,the proposed Software-defined Space-Air-Ground Integrated network architecture could be built as a large,scalable and efficient communication network that could be integrated into space,air,and ground.

关键词： Space-Air-Ground integrated network network architecture software-defined network multi-layer satellite backbone network

Determination of magnesium and aluminum content as principal components in pyrotechnic compositions used for fireworks and firecrackers based on inductively coupled plasma optical emission spectrometric approach （ICP-OES）

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International Journal of Technology Management 2014年第1期 82-86页

作者： Wu Jun-yi Xiao Huan-xin Technical Center for Dangerous Goods Testing of Guangxi Entry-Exit Inspection and Quarantine Bureau 536000BeihaiChina

Inductively coupled plasma optical emission spectrometric approach（ICP-OES）is used to determine the magnesium and aluminum content as principal components in pyrotechnic compositions used for fireworks and firecrackers. Elements of magnesium and aluminum are commonly found in aluminum powder or magnesium-aluminum alloy powder in pyrotechnic compositions in fireworks and firecrackers. Statistical analysis shows that the magnesium content in pyrotechnics is between 8% to 30% and the aluminum content is between 8% to 35%（roughly）.Concept of this method： suppose the weight of the sample is 400rag,constant volume is IL and the concentlation of magnesium and aluminum is between 12mg/L to 160mg/L in sample solution, the determination scope of the method for magnesium and aluminum content would be between 3% to 40%.Further experiments proved that the fitting correlation coefficient of the magnesium calibration curve is 0.9999 or higher, recovery is 101.01% -101.96%.The fitting correlation coefficient of the aluminum calibration curve is 0.9999 or higher, recovery is 99.36%-103.07%. The allowable differential value is 0.4% between two single tests under repeatable conditions. This method can completely satisfy the requirements of the fireworks and firecrackers industry with high accuracy and good precision.

关键词： fireworks and firecrackers:pyrotechnic compositions principal components magnesium aluminum content determination induct ively coupled plasma optical emission spectrometric approach ICP-OES.

Trophic gauntlet effects on fisheries recovery:a case study in Sansha Bay,China

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Ecosystem Health and Sustainability 2021年第1期7卷 318-331页

作者： Bin Xie Cheng Huang Ya Wang Xijie Zhou Guogan Peng Yancheng Tao Jiaju Huang Xiaoqing Lin Lingfeng Huang Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems College of the Environment and EcologyXiamen UniversityXiamen China Fujian Provincial Key Laboratory of Coastal Ecology and Environmental Studies Xiamen UniversityXiamen China Guangxi Key Lab of Mangrove Conservation and Utilization Guangxi Academy of SciencesBeihai China

Low biological productivity causes ecosystem energy *** Bay is an important spawning and nursery ground for migratory fish in the East China Sea(ECS).There is significant mariculture in this area,but stock enhancement programs and seasonal fishery closures have failed to recover populations of the commercially important species,Larimichthys *** want to figure out the potential reason of unsuccessful *** resource in recent 30 *** this study,the trophic status of ***,the food source proportions of *** and zooplankton,and the food web structure and functioning of Sansha Bay was analyzed.A high nutrient low chlorophyll phenomenon was observed:this prevented harmful algal blooms,and phytoplankton growth was restrained by intensive macroalgal culture,resulting in a low abundance of zooplankton in Sansha *** was the most important food source of zooplankton,and zooplankton was the greatest food source of juvenile *** *** suffered from ***,most of the phytoplankton was not used efficiently in the Sansha Bay *** study suggests that trophic bottleneck,caused by food limitation,is a potential reason for unsuccessful fishery recovery in enclosed bay with macroalgal culture.

关键词： High nutrient low chlorophyll ecopath stable isotope mariculture Sansha Bay Larimichthys crocea

The reverse sediment transport trend between abandoned Huanghe River(Yellow River) Delta and radial sand ridges along Jiangsu coastline of China——an evidence from grain size analysis

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Acta Oceanologica Sinica 2012年第6期31卷 83-91页

作者： LIU Tao SHI Xuefa LI Chaoxina YANG Gang Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of SciencesQingdao 266071China Guangxi Mangrove Research Center Beihai 536007China Key Laboratory of Marine Resources and Environmental Geology State Oceanic AdministrationQingdao 266061China Key Laboratory of Marine Resources and Environmental Geology State Oceanic AdministrationQingdao 266061China

To reveal the sediment transporting mechanism between the abandoned Huanghe River （Yellow River） Delta and radial sand ridges, “End Member” Model and grain size trend analysis have been employed to separate the “dynamic populations” in the surficial sediment particle spectra and to determine the possible sediment transporting pathway. The results reveal four “dynamic subpopulations”（EM1 to EM4） and two reverse sediment transporting directions： a northward transport tend from the radial sand ridges to mud patch, and a southward transport trend in deep water area outside the mud patch. Combined with the published hydrodynamic information, the transporting mechanism of dynamic populations has been discussed, and the main conclusion is that the transporting of finer subpopulations EM1 and EM2 is controlled by the “anticlockwise residual current circulation” forming during tidal cycle, which favor a northward transporting trend and the forming of mud patch on the north of radial sand ridges, while the transporting of coarser EM3 is mainly controlled by wind driven drift in winter, which favors a southward transporting direction.

关键词： radial sand ridges sediment transport grain size trend analysis end member model

A Study of Peer Interactions in Language Classroom

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海外英语 2015年第24期 285-286页

作者：许春花 XU Chun-yan 湖南工业大学外国语学院 beihai Middle School

Peer interaction offers multiple benefits to learners and holds great implications for language learning. Peer interaction creates a communication- friendly environment where novice foreign language learners feel more comfortable to use the target language, reinforcing what they have learned and pushing them to rack their brains and reach beyond the zone of proximal development for more. Recently, an increasing number of second language learning studies has begun to investigate peer-peer interaction, focusing more on the social nature of learning. These studies draw upon the framework of Sociocultural Theory, which regards cognition and knowledge as constructed through social interaction.

关键词： peer interactions sociocultural theory language classroom