Studies on Growth-promoting Function and Mechanism of Extract from Grape Seed and Sweet Wormwood on Monopterus albus

[Objectives]The effect and mechanism of grape seed and sweet wormwood extract on growth of Monopterus albus were studied.[Methods]1 500 healthy M.albus with average mass of 23.8 g/tail were randomly divided into 5 groups.The control group was fed with basal diet and the experimental groups were fed with 10,20,30 and 40 g/kg of grape seed and sweet wormwood extract,respectively.The growth performance of the fish was measured after 60 d of feeding at 23-28℃.[Results]The addition of grape seed and sweet wormwood extract in basal diet could increase the body weight gain rate,specific growth rate and protein efficiency,and decrease the feed coefficient.The activity of digestive enzymes,glutamic-oxaloacetic transaminase,glutamic-pyruvic transaminase,blood alkaline phosphatase and serum total protein was increased,and the contents of blood glucose and triglyceride were decreased.Compared with the control group,the above indexes showed significant difference(P<0.05)when the dosage was 20 and 30 g/kg(P<0.05).The difference was not significant(P>0.05)when the dosage was 10 and 40 g/kg(P>0.05).[Conclusions]As a feed additive,the plant extract from grape seed and sweet wormwood could increase digestive enzyme activity and regulate blood biochemical parameters of fish body.It had the function of promoting the digestion and absorption,enhancing the metabolic activity of 3 main nutrients,and hastening the growth of fish.

Hexagonally arranged arrays of urchin-like Ag hemispheres decorated with Ag nanoparticles for surface-enhanced Raman scattering substrates

The surface topography of noble metal particles is a significant factor in tailoring surface-enhanced Raman scattering （SERS） properties. Here, we present a simple fabrication route to hexagonally arranged arrays of surface-roughened urchin- like Ag hemispheres （Ag-HSs） decorated with Ag nanoparticles （Ag-NPs） for highly active and reproducible SERS substrates. The urchin-like Ag-HS arrays are achieved by sputtering Ag onto the top surface of a highly ordered porous anodic aluminum oxide （AAO） template to form ordered arrays of smooth Ag-HSs and then by electrodepositing Ag-NPs onto the surface of each Ag-HS. Owing to the ordered arrangement of the Ag-HSs and the improved surface roughness, the urchin-like hierarchical Ag-HS arrays can provide sufficient and uniform ＂hot spots＂ for reproducible and highly active SERS effects. Using the urchin-like Ag-HS arrays as SERS substrates, 10-7 M dibutyl phthalate （a member of plasticizers family） and 1.5 × 10-5 M PCB-77 （one congener of polychlorinated biphenyl, a notorious class of pollutants） are identified, showing promising potential for these substrates in the rapid recognition of organic pollutants.

Optimal video communication strategy for intelligent video analysis in unmanned aerial vehicle applications

For Unmanned Aerial Vehicles(UAV),the intelligent video analysis is a key technology in intelligent autonomous control,real-time navigation and surveillance.However,poor UAV wireless links would degrade the quality of video communication,leading to difficulties in video analysis.To meet the challenges of packet-loss and limited bandwidth in adverse UAV channel environments,this paper proposes a parameter optimization mechanism for UAV intelligent video analysis.In the proposed method,an Optimal Strategy Library(OSL)is designed to optimize the parameters for video encoding and forward error correction.Adapted to the packet-loss rate and bandwidth in practical UAV wireless network,the proposed OSL can facilitate the encoding of video sequences and the recovery of degraded videos with optimal performance.Experimental results demonstrate that the proposed solution can keep intelligent video analysis working efficiently with adverse UAV wireless links,and is capable of maximizing the inference accuracy of Multi-Object Tracking(MOT)algorithms in various scenarios.

Q460GJEZ35抗震耐蚀耐火特厚钢板的研发

随着越来越多超高层、大跨度建筑工程的开工建设,对建筑结构用钢高强、长寿命、服役安全性等方面提出了更高的要求,发展460 MPa级抗震耐蚀耐火功能复合化建筑用钢具有广阔的市场应用前景。此钢种具有高强韧性、低屈强比、抗层状撕裂和良好的焊接性等性能特点,又兼备耐火性、耐候性等功能,可实现高层建筑用钢厚度减薄,节约钢材用量,同时在不使用防火涂层的情况下能保证高楼大厦在火灾中具备较长时间的承载能力,可广泛应用于较高耐火耐候等级的超高层建筑、大型厂房等钢结构建筑。通过对460 MPa级抗震耐蚀耐火建筑用钢关键技术的对比分析,采用铁水KR脱硫—转炉冶炼—钢包白渣精炼(LF)+钢包真空脱气(VD)精炼—铜板结晶器水冷钢锭模浇铸—钢锭加热—轧机成型—QLT热处理工艺进行试制。成分设计方面,其核心是耐火与耐蚀的复合微合金化设计兼顾其强化作用、晶粒细化作用、耐腐蚀作用、纳米析出相析出行为。为提高其焊接性能,将碳当量控制在0.55以内,通过Cu、Cr、Ni、Mo元素的合理配比实现其高强韧性、耐火、耐蚀功能复合化,同时为降低成本,将贵重合金元素Mo控制在0.30%以下;钢水冶炼方面通过精料入炉、纯净钢冶炼技术实现钢中超低P、超低S、超低O、高纯净度;原始坯料成型采用改进型铜板结晶器水冷锭模,通过定向凝固技术实现钢锭内部微缺陷化;轧制环节通过硬壳法轧制促进表面硬化以使轧制时轧制力渗透至钢板芯部,在提高内部质量的同时实现显微组织均匀细化;热处理环节通过两相区淬火,实现软硬相合理搭配,降低屈强比、细化晶粒,提高冲击韧性。通过成分设计—转炉冶炼—水冷模浇铸—轧制—离线热处理的工艺设计,开发出460 MPa级抗震耐蚀耐火钢板,其屈服强度控制在500~520 MPa、抗拉强度控制在630~650 MPa、伸长率24%~27%,屈强比0.79~0.81,厚度方向断面收缩率均值70%,600℃保温3 h的屈服强度为339~367 MPa,-40℃纵向冲击功200 J以上,耐大气腐蚀性能指数7.5以上,可生产钢板最大厚度150 mm,最大宽度3800 mm,最大长度120000 mm。