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Differences in sensitivity of native and exotic fish species to changes in river temperature

Current Zoology 2011年第6期57卷 852-862页

作者： r.S.E.W. LEUVEN A.j. HENDrIKS M.A.j. HUIjBrEGTS H.j.r. LENderS j. MATTHEWS VAN der VELDE radboud University Nijmegen Institute for Water and Wetland Research Department of Environmental Science Heyendaal- seweg 135 NL-6525 AJ Nijmegen The Netherlands radboud University Nijmegen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology Heyendaalseweg 135 NL-6525 AJ Nijmegen The Netherlands Netherlands Centre for Biodiversity Naturalis P.O. Box 9517 NL-2300 RA Leiden The Netherlands

This paper describes the effects that temperature changes in the rhine river distributaries have on native and exotic fish diversity. Site-specific potentially affected fractions （PAFs） of the regional fish species pool were derived using species sensitivity distributions （SSDs） for water temperature. The number of fish species in the river distributaries has changed remarkably over the last century. The number of native rheophilous species declined up until 1980 due to anthropogenic disturbances such as commercial fishing, fiver regulation, migration barriers, habitat deterioration and water pollution. In spite of progress in river re- habilitation, the native rheophilous fish fauna has only partially recovered thus far. The total number of species has strongly in- creased due to the appearance of more exotic species. After the opening of the rhine-Main-Danube waterway in 1992, many fish species originating from the Ponto-Caspian area colonized the rhine basin. The yearly minimum and maximum river tempera- tures at Lobith have increased by circa 4 ~C over the period 1908-2010. Exotic species show lower PAFs than native species at both ends of the temperature range. The interspecific variation in the temperature tolerance of exotic fish species was found to be large. Using temporal trends in river temperature allowed past predictions of PAFs to demonstrate that the increase in maximum river temperature negatively affected a higher percentage of native fish species than exotic species. Our results support the hy- pothesis that alterations of the river rhine＇s temperature regime caused by thermal pollution and global wanning limit the full recovery of native fish fauna and facilitate the establishment of exotic species which thereby increases competition between native and exotic species. Thermal refuges are important for the survival of native fish species under extreme summer or winter temperature conditions

关键词： Aquatic invaders Global warming Heat discharges Lethal temperature river rhine Thermal heterogeneity

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Cost projections for microwave plasma CO production using renewable energy

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journal of Energy Chemistry 2022年第8期31卷 507-513,I0014页

作者： remko j.Detz Bob van der Zwaan Netherlands Organisation for Applied Scientific research(TNO) Amsterdam 1043 NTThe Netherlands Faculty of Science(HIMS and IAS) University of AmsterdamAmsterdam 1090 GDThe Netherlands School of Advanced International Studies(SAIS) Johns Hopkins UniversityBologna 40126Italy

Successful deployment of renewable fuel production requires substantial cost reduction along the entire value chain of the underlying manufacturing *** improve their performance,renewable fuel production technologies should follow a cost-reducing learning *** this article,we adopt recent evidence that learning-by-doing is directly influenced by the technology unit size and explore three scenarios for microwave plasma CO_(2)conversion in which the learning rate varies between 10%,15%,and 20%.Our projections reveal that the total investments required to deploy this CO_(2)conversion technology at an exajoule scale decline from 83 down to 23 billion euros under a 10%increase in the value of the learning *** CO_(2) production costs in 2050 amount to 247–346€(2019)/t CO_(2),in which the range is determined by the value of the learning *** under substantial learning until 2050 the levelized CO production cost is unlikely to become competitive with conventional natural gas-based CO_(2) production processes,except when a CO_(2)tax is applied of up to 150€(2019)/t CO_(2).To optimally exploit effects of learning-by-doing,we recommend developing several CO production technologies simultaneously with multiple unit sizes,so as to improve the chance of ultimately selecting the process with the highest learning rate.

关键词： CO_(2)utilization Synthetic fuels renewable chemicals Learning curves Unit size

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Two-fluid modeling of Geldart A particles in gas-fluidized beds

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Particuology 2008年第6期6卷 540-548页

作者： M.A. van der Hoef j.A.M. Kuipers Faculty of Science & Technology University of Twente

We have investigated the effect of cohesion and drag models on the bed hydrodynamics of Geldart A particles based on the two-fluid （TF） model. For a high gas velocity U0 = 0.03 m/s, we found a transition from the homogeneous fluidization to bubbling fluidization with an increase of the coefficient C1, which is used to account for the contribution of cohesion to the excess compressibility. Thus cohesion can play a role in the bed expansion of Geldart A particles. Apart from cohesion, we have also investigated the influence of the drag models. When using the Wen and Yu drag correlation with an exponent n = 4.65, we find an under-prediction of the bed expansion at low gas velocities （U0 = 0.009 m/s）. When using a larger exponent （n = 9.6）, as reported in experimental studies of gas-fluidization, a much better agreement with the experimental bed expansion is obtained. These findings suggest that at low gas velocity, a scale-down of the commonly used drag model is required. On the other hand, a scale-up of the commonly used drag model is necessary at high gas velocity （U0 = 0.2 and 0.06 m/s）. We therefore conclude that scaling the drag force represent only an ad hoc way of repairing the deficiencies of the TF model, and that a far more detailed study is required into the origin of the failure of the TF model for simulating fluidized beds of fine powders.

关键词： Gas-fluidized bed Geldart A particles Two-fluid model Cohesive force Drag correlation

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A Space-Time Interior Penalty Discontinuous Galerkin Method for the Wave Equation

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Communications on Applied Mathematics and Computation 2022年第3期4卷 904-944页

作者： Poorvi Shukla j.j.W.van der Vegt Department of Applied Mathematics University of TwenteP.O.Box 2177500 AE EnschedeThe Netherlands

A new higher-order accurate space-time discontinuous Galerkin(DG)method using the interior penalty flux and discontinuous basis functions,both in space and in time,is pre-sented and fully analyzed for the second-order scalar wave *** attention is given to the definition of the numerical fluxes since they are crucial for the stability and accuracy of the space-time DG *** theoretical analysis shows that the DG discre-tization is stable and converges in a DG-norm on general unstructured and locally refined meshes,including local refinement in *** space-time interior penalty DG discre-tization does not have a CFL-type restriction for *** order of accuracy is obtained in the DG-norm if the mesh size h and the time stepΔt satisfy h≅CΔt,with C a positive *** optimal order of accuracy of the space-time DG discretization in the DG-norm is confirmed by calculations on several model *** calculations also show that for pth-order tensor product basis functions the convergence rate in the L∞and L2-norms is order p+1 for polynomial orders p=1 and p=3 and order p for polynomial order p=2.

关键词： Wave equation Space-time methods Discontinuous Galerkin methods Interior penalty method A priori error analysis

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Postoperative surgical site infection in cholesteatoma surgery with and without mastoid obliteration, what can we learn?

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journal of Otology 2022年第1期17卷 25-30页

作者： F.L.j.Cals H.F.E.van der Toom r.M.Metselaar A.van Linge M.P.van der Schroeff r.j.Pauw Department of Otorhinolaryngology and Head and Neck Surgery Erasmus Medical CenterRotterdamthe Netherlands

Introduction:This study aims to describe the occurrence of postoperative complications related to cholesteatoma surgery and to determine factors influencing the most common complication,*** surgical site infection(SSI)in cases with and without mastoid *** and methods:retrospective analyses were performed on surgically treated cholesteatomas in our hospital between 2013 and *** characteristics,peri-and postoperative management and complications were *** cases were divided into two groups based on whether mastoid obliteration was performed or ***:A total of 336 cholesteatoma operations were performed,of which 248 cases received mastoid *** total 21 complications were observed,of which SSI was the most common(15/21).No difference in occurrence of any postoperative complication was seen between the obliteration and noobliteration group(p=0.798),especially not in the number of SSI(p=0.520).Perioperative and/or postoperative prophylactic antibiotics were not associated to the development of an SSI in both *** the no-obliteration group a younger age(p=0.015),as well as primary surgery(p=0.022)increased the risk for *** the obliteration group the use of bioactive glass(BAG)S53P4 was identified as independent predictor of SSI(p=0.008,Or 5.940).Discussion:SSI is the most common postoperative complication in cholesteatoma *** causes of SSI are multifactorial,therefore further prospective research is needed to answer which factors can prevent the development of an SSI in cholesteatoma surgery.

关键词： Cholesteatoma Mastoid obliteration Postoperative surgical site infection Complications Bioactive glass S53P4

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Three-Phase PWM Power Conversion—The route to Ultra High Power Density and Efficiency

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电力电子技术 2005年第6期39卷 2-9,18页

作者： j W Kolar j Minibck T Nussbaumer Swiss Federal Institute of Technology (ETH) Zurich Power Electronic Systems LaboratoryETH Zentrum / ETL H22 Physikstr. 3 CH-8092 Zurich/Switzerland

A review of three-phase PWM converter topologies which do show a low complexity/high reliability and high efficiency and power density and are therefore of main interest for a future industrial application is presented.A three-switch/level Boost-type PWM rectifier(VIENNA rectifier),a Buck+Boost-type PWM rectifier with wide output voltage range and the AC/AC Sparse Matrix Converter concept are discussed in detail and topics to be treated in the course of further research are ***,it is shown how the aspects being relevant for the realization of highly compact converter systems could be integrated into education in the field.

关键词： PWM 能量转换整流器三相交流电能量效率

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奥钢联Schienen公司在累奥本/多纳维茨新建现代化钢轨轧机

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钢铁 2006年第10期41卷 82-86页

作者： H.Pfeiler N.Kck j.Schrder L.Maestrutti 杨秋霜奥钢联Schienen公司

介绍了奥钢联Schienen公司在累奥本/多纳维茨新建的现代化钢轨轧机的设备情况及其技术特点。该轧机在轧制钢轨时采用万能轧制模式。这种轧制模式与SCC机芯概念机架的组合,可获得极高的产品加工精度,使钢轨成品表面质量更好,延长轧辊使... 详细信息

介绍了奥钢联Schienen公司在累奥本/多纳维茨新建的现代化钢轨轧机的设备情况及其技术特点。该轧机在轧制钢轨时采用万能轧制模式。这种轧制模式与SCC机芯概念机架的组合,可获得极高的产品加工精度,使钢轨成品表面质量更好,延长轧辊使用寿命,使钢轨对称成形,降低内应力。

关键词：钢轨轧机达涅利技术特点

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The off-host survival and viability of a native and non-native fish louse （Argulus, Crustacea： Branchiura）

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Current Zoology 2011年第6期57卷 828-835页

作者： P.D. WALKEr I.j. rUSSON r. DUIjF G. VAN der VELDE S.E. WENDELAAr BONGA radboud University of Nijmegen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands APEM Ltd Centre for Innovation ＆ Enterprise Begbroke Science Park Sandy Lane Yarnton Oxfordshire OX5 1PF United Kingdom Netherlands Centre for Biodiversity Naturalis P.O. Box 9517 2300 RA Leiden The Netherlands

Fish ectoparasites are introduced to water bodies or aquaculture systems along with their hosts. Argulid fish lice can survive off-host for a given time, and in spite of quarantine measures might also be introduced via the transfer of water. However, they must cope with varying abiotic conditions without access to food. We investigated the effect of temperature （5 to 28℃） on the off-host survival time of Argulus japonicus, an invasive species which is apparently increasing its distribution, and compared this with the European A. foliaceus. A clear effect of temperature on the off-host survival time of all stages of both species was demonstrated. Larval and juvenile A. japonicus survived up to 9 days at 22℃ and in the case of adults up to 13 days at 15℃. By comparison, larval A. foliaceus survived up to 5 days at 15℃, adults up to 14 days at 9℃ and juveniles up to 7 days at 9℃ and 15℃. Thus, A. japonicus is more resistant to starvation at higher temperatures under controlled off-host conditions and A. foli- aceus is more resistant to starvation at lower temperatures. Infectivity of A. japonicus decreased linearly with the time spent off-host after 2 days for larvae and 4 days for adults. Temperature only had a significant effect on the infectivity of both develop- mental stages after 24 hours off-host between 13-23℃ for larvae and 13-18℃ for adults. In conclusion both species can potentially survive off-host pelods in water transports for up to 13-14 days as adults. Their survival is shorter as larvae. This study demonstrates that transportation of water has the potential to introduce Argulus species

关键词： Argulus Fish lice Survival Temperature Off-host Water transport Introductions Invasive species

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Diffusion weighted imaging in the liver

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World journal of Gastroenterology 2010年第13期16卷 1567-1576页

作者： Petra G Kele Eric j van der jagt Department of radiology University Medical Center Groningen University of Groningen

Diffusion weighted magnetic resonance imaging (DWI) is an imaging technique which provides tissue contrast by the measurement of diffusion properties of water molecules within tissues. Diffusion is expressed in an apparent diffusion coefficient (ADC), which reflects the diffusion properties unique to each type of tissue. DWI has been originally used in neuroradiology. More recently, DWI has increasingly been used in addition to conventional unenhanced and enhanced magnetic resonance imaging (MrI) in other parts of the body. The reason for this delay was a number of technical problems inherent to the technique, making DWI very sensitive to artifacts, which had to be overcome. With assessment of ADC values, DWI proved to be helpful in characterization of focal liver lesions. However, DWI should always be used in conjunction to conventional MrI since there is considerable overlap between ADC values of benign and malignant lesions. DWI is useful in the detection of hepatocellular carcinoma in the cirrhotic liver and detection of liver metastases in oncological patients. In addition, DWI is a promising tool in the prediction of tumor responsiveness to chemotherapy and the follow-up of oncological patients after treatment, as DWI may be capable of detecting recurrent disease earlier than conventional *** review focuses on the most common applications of DWI in the liver.

关键词： Diffusion Magnetic resonance imaging Diffusion weighted imaging Benign neoplasms Liver neoplasms

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One-Step reverse Osmosis Based on riverbank Filtration for Future Drinking Water Purification

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Engineering 2022年第2期8卷 27-34页

作者： Yujia Zhai Gang Liu Walter G.j.van der Meer Oasen Drinkwater Gouda 2800 ACNetherlands Faculty of Science and Technology University of TwenteEnschede 7500 AENetherlands Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Sanitary Engineering research Group Department of Water ManagementFaculty of Civil Engineering and GeosciencesDelft University of TechnologyDelft 2600 GANetherlands

The presence of newly emerging pollutants in the aquatic environment poses great challenges for drink-ing water treatment *** to their low concentrations and unknown characteristics,emerging pol-lutants cannot be efficiently removed by conventional water treatment processes,making technically,economically,and environmentally friendly water purification technologies increasingly *** article introduces a one-step reverse osmosis(OSrO)concept consisting of riverbank filtration(rBF)and reverse osmosis(rO)for drinking water *** OSrO concept combines the relatively low-cost natural pretreatment of river water with an advanced engineered purification *** pro-vides a continuous natural source of water with stable water quality and a robust barrier for *** the pre-removal of particles,organic matter,organic micro-pollutants(OMPs),and microbes,rBF becomes an ideal source for a purification system based on rO membranes,in comparison with the direct intake of surface *** treatment removes almost 99.9%of the particles,pathogens,viruses,and OMPs,as well as the vast majority of nutrients,and thus meets the requirements for the chlorine-free delivery of drinking water with high *** OSrO treatment is cost effective com-pared with the standard conventional series of purification steps involving sprinkling filters,softening,and activated *** bank filtration(ABF),which functions as an artificial recharge in combi-nation with a sand filtration system,is proposed as an alternative for rBF in the OSrO concept to supply drinking water from locally available *** is also suggested that the OSrO concept be imple-mented with wind power as an alternative energy source in order to be more sustainable and *** OSrO-based decentralized water system is proposed for water reclaiming and *** is suggested that future water treatment focus on the combination of natural and engineered systems to pro

关键词： Drinking water treatment river bank filtration reverse osmosis Artificial bank filtration Water reclamation and reuse

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