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experiments and evidences: jellyfish (Nemopilema nomurai) decomposing and nutrients (nitrogen and phosphorus) released

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Acta Oceanologica Sinica 2015年第8期34卷 1-12页

作者： LI Xuegang SONG Jinming MA Qingxia LI Ning YUAN Huamao DUAN Liqin QU Baoxiao Institute of Oceanography Chinese Academy of Sciences University of Chinese Academy of Sciences

The aim of this study was to investigate nitrogen and phosphorus released in the process of the decomposition of giant jellyfish in the laboratory and found the evidence to verify the influence of nutrients released by the decomposition of jellyfish on the ecosystem in the field. The release of nitrogen and phosphorus from the decomposition of Nernopilerna nomurai was examined in a series of experiments under different incubation conditions such as different pH values, salinity values, temperatures and nitrogen and phosphorus concentrations. The results showed that the complete decomposition of Nemopilema nomurai generally took about 4-8 d. The release of nitrogen and phosphorus from the decomposition of Nemopilema nomurai could be divided into two stages： the early stage and the later stage, although the efflux rate of nitrogen was one order more than phosphorus. In the early stage of the decomposition of Nemopilema nomurai, the concentrations of dissolved nitrogen, dissolved phosphorus, total nitrogen and total phosphorus in seawater increased rapidly, and the concentration of nitrogen could reach the highest level in the whole degradation process. In the later stage of the decomposition, the concentrations of dissolved nitrogen and total nitrogen declined slowly, while the concentration of phosphorus in water could reach a maximum in the degradation process. High pH, low salinity, high temperature and N/P will promote the release of nitrogen; low pH is unfavorable to the release of nitrogen but favorable to the release of phosphorus. In addition, we found the concentrations of ammonium and phosphate in the bottom water were higher than those in the surface water during the period of jellyfish bloom in the ]iaozhou Bay, proving that nutrients released by the decomposition of jellyfish have significant influence on nitrogen and phosphorus in the field. For the whole Yellow Sea, nutrients released by jellyfish carcasses may reach up to （2.63±2.98）x10^7 mol/d of diss

关键词： Nemopilema nomurai decomposition nitrogen phosphorus experiments evidences

In situ experiments on width and evolution characteristics of excavation damaged zone in deeply buried tunnels

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Science China(Technological Sciences) 2011年第S1期54卷 167-174页

作者： LI ShaoJun 1,FENG XiaTing 1,LI ZhanHai 3,CHEN BingRui 1,JIANG Quan 1,WU ShiYong 2,HU Bin 2 &XU JinSong 2 1 State Key Laboratory of Geomechanics and Geotechinical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China 2 Ertan Hydropower Development Company,Ltd.,Chengdu 610051,China 3 School of Resources and Civil Engineering,Northeastern University,Shenyang 110004,China 1. State Key Laboratory of Geomechanics and Geotechinical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China3. School of Resources and Civil Engineering Northeastern University Shenyang 110004 China2. Ertan Hydropower Development Company Ltd. Chengdu 610051 China

The seven long tunnels of Jinping II hydropower station are deeply *** width and evolution characteristics of excavation damaged zone(EDZ) are the key problem to the design of tunnels excavation and *** order to study this problem,several specific experimental tunnels with different overburden and geometric sizes were excavated at this *** borehole camera,sliding micrometer,cross-hole acoustic wave equipment and acoustic emission apparatus were *** paper introduced the comprehensive in situ experimental methods through pre-installed facilities and pre-drilled *** properties of the surrounding rock mass,including cracks,deformation,elastic wave and micro fractures,were measured during the whole process of the tunnel *** width and characteristics of formation and evolution of tunnels EDZ were analyzed under different construction methods involving of TBM and drilling and blasting,the test tunnels were excavated by full-face or two *** relationships between EDZ and tunnel geometry sizes,overburden and excavation method were described as *** results will not only contribute a great deal to the analysis of rock mass behavior in deeply buried rock mass,but also provide direct data for support design and rockburst prediction.

关键词： deeply buried tunnel excavation damaged zone evolution characteristics in situ experiments

NR-PSS (Nonlinear Robust Power System Stabilizer) for large synchronous generators and its large disturbance experiments on real time digital simulator

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Science China(Technological Sciences) 2008年第4期51卷 337-352页

作者： LU Qiang ZHENG ShaoMing MEI ShengWei WANG Gang HUANG QiLi State Key Lab of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Northeast China Grid Company Shenyang 110006China

On the foundation of nonlinear robust control and exact generator model, this paper presents a design principle of NR-PSS (Nonlinear Robust Power System Stabilizer) for multi-machine power system, based on which an industrial NR-PSS equipment is developed. For popularizing it, the proposed parameter setting method of NR-PSS is completely the same as the widely used parameter adjustment rule of PSS. By virtue of real time digital simulator (RTDS), large disturbance experiments are carried out to compare the performances between generator excitation system equipped with NR-PSS and PSS in order to verify the correctness of design theory. The results show that compared with classical PSS, the proposed NR-PSS can dramatically improve the generator damping and attenuate the oscillation much faster, enhance the generator damping and raise both the small signal and large disturbance transient stability transmission power limit remarkably. The NR-PSS equipment with independent intellectual property right has been successfully put into operation on a 300 MW generator in Baishan Hydro Plant of Northeast China Grid more than 10 months.

关键词： nonlinear robust control power system stabilizer real time digital simulation system large disturbance experiments

Monitoring system experiments on beam loss at SSRF injector

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 279-282页

作者： CAI Jun XIA XiaoBin XU XunJiang LIU Xin XU JiaQiang WANG GuangHong ZENG Ming Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Department of Engineering Physics Tsinghua UniversityBeijing 100084China

experiments on beam loss by using beam loss monitoring (BLM) system were carried out at Shanghai Synchrotron Radiation Facility (SSRF) injector. This system used highly sensitive and current-integrated Si-photodiode detectors and an Ethernet data acquisition (DAQ) system. The experimental results demonstrate that the Si-photodiode detectors are a useful tool that provides dynamic information on beam loss and investigates problems of machine operation. It also shows that the Si-photodiode BLM system is suitable for pulse-radiation of high-energy accelerators.

关键词： Si-photodiode beam loss monitoring (BLM) experiments Ethernet

First radiative shock experiments on the SG-II laser

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High Power Laser Science and Engineering 2021年第2期9卷 193-200页

作者： Francisco Suzuki-Vidal Thomas Clayson Chantal Stehlé Uddhab Chaulagain Jack W.D.Halliday Mingying Sun Lei Ren Ning Kang Huiya Liu Baoqiang Zhu Jianqiang Zhu Carolina De Almeida Rossi Teodora Mihailescu Pedro Velarde Manuel Cotelo John M.Foster Colin N.Danson Christopher Spindloe Jeremy P.Chittenden Carolyn Kuranz Blackett Laboratory Imperial College LondonLondonUK First Light Fusion Ltd YarntonUK LERMA Sorbonne-UniversitéObservatoire de ParisCNRSFrance ELI Beamlines Center Institute of PhysicsCzech Academy of SciencesDolni BrezanyCzech Republic Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghaiChina Instituto de Fusión Nuclear Guillermo Velarde Universidad Politécnica de MadridMadridSpain AWE plc. AldermastonReadingUK Science and Technology Facilities Council Rutherford Appleton LaboratoryHarwell CampusChiltonDidcotUK University of Michigan Ann ArborMIUSA Current affiliation:Magdrive Ltd HarwellUK

We report on the design and first results from experiments looking at the formation of radiative shocks on the ShenguangII(SG-II)laser at the Shanghai Institute of Optics and Fine Mechanics in ***-heating of a two-layer CH/CH–Br foil drives a∼40 km/s shock inside a gas cell filled with argon at an initial pressure of 1 *** use of gas-cell targets with large(several millimetres)lateral and axial extent allows the shock to propagate freely without any wall interactions,and permits a large field of view to image single and colliding counter-propagating shocks with time-resolved,pointprojection X-ray backlighting(∼20µm source size,4.3 keV photon energy).Single shocks were imaged up to 100 ns after the onset of the laser drive,allowing to probe the growth of spatial nonuniformities in the shock *** results are compared with experiments looking at counter-propagating shocks,showing a symmetric drive that leads to a collision and stagnation from∼40 ns *** present a preliminary comparison with numerical simulations with the radiation hydrodynamics code ARWEN,which provides expected plasma parameters for the design of future experiments in this facility.

关键词： high energy density physics laboratory astrophysics plasma physics high-power laser laser-driven shocks experiments X-ray backlighting X-ray radiography

Compressive behavior of hybrid steel-polyvinyl alcohol fiber-reinforced concrete containing fly ash and slag powder:experiments and an artificial neural network model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第9期22卷 721-735页

作者： Fang-yu LIU Wen-qi DING Ya-fei QIAO Lin-bing WANG Qi-yang CHEN Department of Civil and Environmental Engineering Virginia Polytechnic Institute and State UniversityVirginia 24061USA Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering Ministry of EducationShanghai 200092China Department of Civil and Environmental Engineering University of Illinois at Urbana-ChampaignUrbana 61801USA

Understanding the mechanical behavior of hybrid fiber-reinforced concrete(HFRC),a composite material,is crucial for the design of HFRC and HFRC *** this study,a series of compression experiments were performed on hybrid steelpolyvinyl alcohol(PVA)fiber-reinforced concrete containing fly ash and slag powder,with a focus on the fiber content/ratio effect on its compressive behavior;a new approach was built to model the compression behavior of HFRC by using an artificial neural network(ANN)*** proposed ANN model incorporated two new developments:the prediction of the compressive stress-strain curve and consideration of 23 features of components of *** build a database for the ANN model,relevant published data were also *** indices were used to train and evaluate the ANN *** highlight the performance of the ANN model,it was compared with a traditional equation-based *** results revealed that the relative errors of the predicted compressive strength and strain corresponding to compressive strength of the ANN model were close to 0,while the corresponding values from the equation-based model were ***,the ANN model is better able to consider the effect of different components on the compressive behavior of HFRC in terms of compressive strength,the strain corresponding to compressive strength,and the compressive stress-strain *** an ANN model could also be a good tool to predict the mechanical behavior of other composite materials.

关键词： experiments Artificial neural network(ANN) Hybrid fiber-reinforced concrete(HFRC) Compressive behavior Stress-strain curve

Spread spectrum-based ultraviolet communication with experiments

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Chinese Optics Letters 2014年第10期12卷 5-11页

作者：张民罗鹏飞郭晓雪张翔韩大海李青 State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

We report experiments of ultraviolet （UV） communication based on spread-spectrum technique. Field measurements via online UV communication are conducted to compare the system performances with and without spectrum spreading. The results indicate that the spread-spectrum technique is capable of suppressing noise in UV atmospheric scattering channel and therefore improve the system performance evidently. Details of implementation are also provided to make the results useful for similar system design in research on optical wireless communications.

关键词： experiments Spectroscopy Wireless telecommunication systems

experiments ON FLOW AROUND A CYLINDER IN A SCOURED CRANNEL BED

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International Journal of Sediment Research 2001年第4期 431-444页

作者： I. ISTIARTO and W.H. GRAF 1 Res. Asst., Lab. de recherches hydrauliques, Ecole Polytechnique Federale, Lausanne, Switzerland. E-mail: adhy.kurniawan@epfl.ch or istiarto@tsipil.ugm.ac.id 2 Prof, Lab. de recherches hydrauliques, Ecole Polytechnique Federal

The flow pattern around a cylinder, installed in a scourd channel bed, was experimentally investigated. Detailed measurements of the instantaneous 3D velocities were performed by using an Acoustic Doppler Velocity Profiler (ADVP), from which the profiles of the time~averaged velocities and turbulence stresses were obtained. It is shown that the influence of thC cylinder and of the scour hole alters the approach flow; this is essentially confined to the viciulty of the cylinder and to the inside of the scour hole. The horseshoe vortex is measured as a flow reversal inside the scour hole, formed by the downward flow along the cylinder face and the reversed flow at the scour bed.

关键词： Open channel flow Flow around cylinder Local scour experiments

<i>In Silico</i>experiments of Carbon Dioxide Atmosphere and Buffer Type Effects on the Biomimetic Coating with Simulated Body Fluids

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Advances in Materials Physics and Chemistry 2012年第4期2卷 239-248页

作者： Gustavo M. Platt Ivan N. Bastos Monica C. Andrade Glória D. A. Soares Federal University of Rio de Janeiro Rio de Janeiro Brazil State University of Rio de Janeiro Nova Friburgo Brazil

The formation of calcium phosphate phases is extremely important in a biomedical engineering context. These phosphates are used in many applications, such as grafts, drug-delivery processes and evaluation of the bioactivity of metallic surfaces. Considering this scenario, it is useful to evaluate the thermodynamic conditions for the precipitation of phosphates of biomedical interest, mainly hydroxyapatite. In this work, we investigate the effects of two important factors using a thermodynamic framework: 1) carbon dioxide partial pressure;and 2) buffer type (2-Amino-2-hydroxy- methyl-propane-1,3-diol, known as TRIS and 2-[4-(2-hydroxyethyl)piperazin-1-yl] ethanesulfonic acid, also called HEPES), on the driving force behind the precipitation of calcium phosphates in simulated body fluids. The in silico results show that the pH value is governed by carbon dioxide content, as expected to occur in vivo. Moreover, the buffers can deplete the free calcium available in solution and, consequently, can cause difficulties in the calcium phosphate precipitation.

关键词： Hydroxyapatite Thermodynamic Modelling Carbon Dioxide HEPES and TRIS Buffers In Silico experiments