【摘 要】
：
Surrounded by emerging markets with considerable plastic consumption,the South China Sea has been a focus area of microplastic research.A survey on the floating microplastics (＞ 0.3 mm) and microplastics ingested by fish and mollusks was conducted around
【机 构】
：
Third Institute of Oceanography,Ministry of Natural Resources,Xiamen 361005,China
论文部分内容阅读
Surrounded by emerging markets with considerable plastic consumption,the South China Sea has been a focus area of microplastic research.A survey on the floating microplastics (＞ 0.3 mm) and microplastics ingested by fish and mollusks was conducted around three remote islands here.Compared with the results from several previous studies,a high abundance of floating microplastics(with a median of 1.9 × 105 items/km2 or 0.7 items/m3) was observed,revealing another “hot spot” for microplastics.Polyolefin,especially polypropylene,was the main component.The diversity index and evenness index were calculated and evaluated based on the composition of microplastics.The characteristic peaks of Raman spectra concerning pigmented microplastics were provided.Transparent sheets/films were predominant in the water sample,which was quite different from a similar study in this sea area (8.9％ for film),and only 16.4％ of floating microplastics (＞ 0.3 mm) were fibers/lines,implying that the main sources of floating microplastics (＞ 0.3 mm) might be household/agricultural consumption activities.The transparent fiber/line was also dominant in organisms.It is suggested that the main sources of microplastics ingested by organisms might be both fabric fibers and fishing/aquaculture.
其他文献
Understanding the fate and toxicity of microplastics (MPs,＜ 5 mm plastic particles) is limited by quantification methods.This paper summarizes the methods in use and presents new ones.First,sampling and pretreatment processes of MPs,including sample colle
通过大型振动台模型试验研究了减震层效能评定方法的准确性和减震层作用下衬砌结构与最不利的IV级和V级围岩在激振过程中的相互作用.研究结果表明:减震层效能评定方法可以较为准确地评估减震层在地震动力作用下对衬砌结构的作用效果,但随着激振加速度峰值的提高,试验值会与评估值产生偏差,因此对减震层效能评定方法引入地震动力损伤系数以提高其精确度;围岩级别相较于减震层的厚度对衬砌结构的地震响应更具有决定性作用;在中低烈度地震区,减震层对衬砌结构的保护效果较为明显,但减震层存在最优厚度,超过该厚度,衬砌结构遭遇地震时的震动
In view of increasing Microplastics (MPs) contamination in the marine environment and dearth of baseline data,a study was conducted on the abundance,characterization,and seasonal distribution of MPs in the nearshore sediments of the south-east coast of In
This paper presents a new approach for automatical classification of structural state through deep learning.In this work,a Convolutional Neural Network (CNN) was designed to fuse both the feature extraction and classification blocks into an intelligent an
Many studies have investigated the effects of different pretreatments on the performance of anaerobic digestion of sludge.However,the detailed changes of dissolved organic nitrogen,particularly the release behavior of proteins and the byproducts of protei
微分求积法和单步块方法都是单步多级数值方法,但是直接应用于求解非线性动力方程时的计算量比较巨大,为此提出了一种基于单步块方法的改进精细积分单步方法.结合精细积分法,该方法采用s级的单步块方法的第s个方程对Duhamel积分项进行数值积分.具体采用四阶Runge-Kutta法获得待求变量的预估值,并采用新四点积分公式计算Duhamel积分项.相对于现有的单步方法,该改进算法在数值精度和稳定性上更优.通过非线性动力方程的典型算例验证了该算法的优势.
Previous studies demonstrated that the El Ni(n)o-Southern Oscillation (ENSO) could modulate regional climate thus influencing air quahty in the low-middle latitude regions like southern China.However,such influence has not been well evaluated at a long-te
Chlorine is often used in algal removal and deodorization of landscape waters,and occasionally used as an emergency treatment of heavily polluted sediments.However,the ecological impact of this practice has not been fully studied and recognized.In this st
采用多弧离子镀技术制备了不同调制比的交替多元多层Zr/CrAlSiN复合涂层,通过交替沉积与间歇性接近不同靶材相结合的方法获得了Zr/[Al(Si)N/CrN]“层中层”结构,并对复合涂层的力学性能、无腐蚀时的摩擦磨损性能、无摩擦磨损时的腐蚀性能及海水环境中的腐蚀磨损性能进行了研究.结果 表明:该结构设计对涂层生长缺陷具有明显的抑制和修复作用;随着CrAlSiN层厚度比例增大,调制比为1∶6时Zr/[Al(Si)N/CrN]涂层的综合力学性能最佳;由于CrAlSiN层具有多层Al(Si)N/CrN结构,增
基于四立柱的台架试验是整车开发过程中可靠性评价的重要方式,当前以试验场整车载荷采集-路谱迭代的试验方式需要对每一个车型均进行实车载荷测量,存在试验周期长且产品可靠性不足时改进成本高等问题.以同一试验场可靠性规范下不同车型载荷相似性基础,开展整车四立柱台架试验载荷谱的标准化研究.分析四种车型整车四立柱台架试验载荷特征,确定各路况下不同车型同一车轮在时域、频域及损伤域的相似性,左右轮载荷时域相关及频域相干、前后轮载荷间时延特征;以同一车轮的功率谱密度分布拟合,选取覆盖一定百分位水平的功率谱作为目标重构单侧车轮