检索结果-南通市图书馆

Single and multiple stressor effect of road deicers and Cu on Atlantic salmon (Salmo salar) alevins from hatching till swim-up

引用

Journal of Environmental Sciences 2018年第4期30卷 368-378页

作者： Urma Mahrosh BjФrn Olav Rosseland Brit Salbu Hans-Christian Teien Nortuegian Uniuersity of Life Sciences Department of Environmental Sciences N-1432 As Norway National University of Sciences and Technology H-12 Islamabad Pakistan Norwegian University of Life Sciences Department of Ecology and Natural Resource Management N-1432 As Norway

Road salts are frequently used for deicing of roads in the Nordic countries. During snow-melt, the road run-off containing high concentrations of road salt and various metals such as Cu remobilized from sand, silt and dust may negatively influence organisms in downstream receiving water bodies. The present work focuses on the impact of road salt（NaCl） and Cu, separately and in mixtures on Atlantic salmon alevins from hatching till swim-up. The results showed that high road salt concentrations could induce a series of negative effects in alevins such as reduced growth, deformities, delayed swim-up and mortality. For alevins exposed to all tested road salt concentrations（100–1000 mg/L）,mortality was significantly higher compared to control. In exposure to Cu solutions（5–20 μg Cu/L）, no effects on growth, morphology, swim-up or mortality of alevins compared to control were observed. In mixture solutions（road salt and Cu）, ultrafiltration of the exposure water demonstrated that only 20%–40% of Cu was present as positively charged low molecular mass（LMM） Cu species assumed to be bioavailable. When exposed to road salt and Cu mixtures, negative effects in alevins such as reduced growth, deformities,delayed swim-up and mortality were observed. The overall results indicated that the road salt application could seriously affect sensitive life stages of Atlantic salmon, and application of road salt should be avoided during the late winter–early spring period.

关键词： Road deicers Copper Atlantic salmon Alevins Biological effects

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Construction of Conservative Numerical Fluxes for the Entropy Split Method

引用

Communications on Applied Mathematics and Computation 2023年第2期5卷 653-678页

作者： Björn Sjögreen H.C.Yee Multid Analyses AB GothenburgSweden NASA Ames Research Center Moffett FieldCA 94035USA

The entropy split method is based on the physical entropies of the thermally perfect gas Euler *** Euler flux derivatives are approximated as a sum of a conservative portion and a non-conservative portion in conjunction with summation-by-parts(SBP)difference boundary closure of(Gerritsen and Olsson in J Comput Phys 129:245-262,1996;Olsson and Oliger in RIACS Tech Rep 94.01,1994;Yee et *** J Comp Phys 162:33-81,2000).Sj?green and Yee(J Sci Comput)recently proved that the entropy split method is entropy conservative and ***-ard high-order spatial central differencing as well as high order central spatial dispersion relation preserving(DRP)spatial differencing is part of the entropy stable split methodol-ogy *** current work is our first attempt to derive a high order conservative numerical flux for the non-conservative portion of the entropy splitting of the Euler flux *** to the construction,this conservative numerical flux requires higher oper-ations count and is less stable than the original semi-conservative split ***,the Tadmor entropy conservative(EC)method(Tadmor in Acta Numerica 12:451-512,2003)of the same order requires more operations count than the new *** the entropy split method is a semi-conservative skew-symmetric splitting of the Euler flux derivative,a modified nonlinear filter approach of(Yee et *** J Comput Phys 150:199-238,1999,J Comp Phys 162:3381,2000;Yee and Sj?green in J Comput Phys 225:910934,2007,High Order Filter Methods for Wide Range of Compressible flow *** of the ICOSAHOM09,June 22-26,Trondheim,Norway,2009)is proposed in conjunction with the entropy split method as the base method for problems containing shock ***-time integration of 2D and 3D test cases is included to show the com-parison of these new approaches.

关键词： Finite-difference method Entropy conservation Entropy splitting Shock capturing

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Phylogenetic biogeography and taxonomy of disjunctly distributed bryophytes

引用

Journal of Systematics and Evolution 2009年第5期47卷 497-508页

作者： Jochen HEINRICHS Jrn HENTSCHEL Kathrin FELDBERG Andrea BOMBOSCH Harald SCHNEIDER Department of Systematic Botany Albrecht von Haller Institute of Plant SciencesGeorg-August-University Botany Department Natural History Museum

More than 200 research papers on the molecular phylogeny and phylogenetic biogeography of bryophytes have been published since the beginning of this *** papers corroborated assumptions of a complex genetic structure of morphologically circumscribed bryophytes,and raised reservations against many morphologically justified species concepts,especially within the ***,many molecular studies allowed for corrections and modifications of morphological classification *** studies reported that the phylogenetic structure of disjunctly distributed bryophyte species reflects their geographical ranges rather than morphological *** data led to new appraisals of distribution ranges and allowed for the reconstruction of refugia and migration *** ranges of bryophytes are often caused by dispersal rather than geographical *** distribution patterns of disjunct bryophytes are likely formed by processes such as short distance dispersal,rare long distance dispersal events,extinction,recolonization and diversification.

关键词： bryophytes cryptic speciation disjunctions divergence time estimates Diversity Arrays Technology DNA sequence variation isozymes molecular phylogeny.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Optimisation of chemical purification conditions for direct application of solid metal salt coagulants:Treatment of peatland-derived diffuse runoff

引用

Journal of Environmental Sciences 2013年第4期25卷 659-669页

作者： Elisangela Heiderscheidt Jaakko Saukkoriipi Anna-Kaisa Ronkanen Bjφrn Klφve Water Resources and Environmental Engineering Laboratory Department of Process and Environmental Engineering90014 University of OuluFinland Finnish Environment Institute(SYKE) Freshwater CentreMonitoring and AssessmentP.O.Box 413FI-90014University of OuluFinland

The drainage of peatland areas for peat extraction, agriculture or bioenergy requires affordable, simple and reliable treatment methods that can purify waters rich in particulates and dissolved organic carbon. This work focused on the optimisation of chemical purification process for the direct dosage of solid metal salt coagulants. It investigated process requirements of solid coagulants and the influence of water quality, temperature and process parameters on their performance. This is the first attempt to provide information on specific process requirements of solid coagulants. Three solid inorganic coagulants were evaluated： aluminium sulphate, ferric sulphate and ferric aluminium sulphate. Pre-dissolved aiuminium and ferric sulphate were also tested with the objective of identifying the effects of in-line coagulant dissolution on purification performance. It was determined that the pre-dissolution of the coagulants had a significant effect on coagulant performance and process requirements. Highest purification levels achieved by solid coagulants, even at 30% higher dosages, were generally lower （5%-30%） than those achieved by pre-dissolved coagulants. Furthermore, the mixing requirements of coagulants pre-dissolved prior to addition differed substantially from those of solid coagulants. The pH of the water samples being purified had a major influence on coagulant dosage and purification efficiency. Ferric sulphate （70 mg/L） was found to be the best performing solid coagulant achieving the following load removals： suspended solids （59%-88%）, total organic carbon （56%-62%）, total phosphorus （87%-90%）, phosphate phosphorus （85%-92%） and total nitrogen （33%-44%）. The results show that the use of solid coagulants is a viable option for the treatment of peatland-derived runoff water if solid coagulant-specific process requirements, such as mixing and settling time, are considered.

关键词： inorganic solid coagulant peatland runoff mixing chemical purification nutrients humic substances

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The differential benefit of laparoscopic over open minor liver resection for lesions situated in the anterolateral or posterosuperior segments

引用

Hepatobiliary Surgery and Nutrition 2024年第4期13卷 604-615,I0015-I0021页

作者： Jasper P.Sijberden Guido Fiorentini Jacopo Lanari Davit Aghayan Daniel Osei-Bordom Nadia Russolillo Arjun Takhar Andrea Benedetti Cacciaguerra Santi Lopez-Ben Mathieu D’Hondt Felice Giuliante David Fuks Fernando Rotellar Andrea Ruzzenente Adnan Alseidi Mikhail Efanov Burak Görgec Giuseppe Zimmitti Enrico Gringeri Federica Cipriani Åsmund Avdem Fretland Ravi Marudanayagam Marco Vivarelli John N.Primrose Alessandro Ferrero Robert P.Sutcliffe Bjørn Edwin Umberto Cillo Marc G.Besselink Mohammad Abu Hilal Luca A.Aldrighetti Department of Surgery Fondazione Poliambulanza Istituto OspedalieroBresciaItaly Amsterdam UMC location University of Amsterdam Department of SurgeryAmsterdamthe Netherlands Cancer Center Amsterdam Amsterdamthe Netherlands Hepatobiliary Surgery Division IRCCS San Raffaele HospitalMilanItaly Department of Surgical Oncological and Gastroenterological SciencesGeneral Surgery 2Hepatobiliary Surgery and Liver TransplantationPadua University HospitalPaduaItaly The Intervention Centre and Department of HPB Surgery Oslo University Hospital and Institute of Clinical MedicineUniversity of OsloOsloNorway Department of Surgery Ringerike HospitalVestre Viken Hospital TrustDrammenNorway Liver Unit Queen Elizabeth HospitalBirminghamUK Department of General and Oncological Surgery Umberto I Mauriziano HospitalLargo TuratiTurinItaly Department of Surgery University Hospital Southampton NHS Foundation TrustSouthamptonUK Hepatobiliary and Abdominal Transplantation Surgery Department of Experimental and Clinical MedicineRiuniti HospitalPolytechnic University of MarcheAnconaItaly Servei de Cirurgia General i Digestiva Hospital Doctor Josep Trueta de GironaGironaCataloniaSpain Department of Digestive and Hepatobiliary/Pancreatic Surgery Groeninge HospitalKortrijkBelgium Chirurgia Epatobiliare UniversitàCattolica del Sacro Cuore-IRCCSRomeItaly Department of Digestive Oncologic and Metabolic SurgeryInstitut Mutualiste MontsourisUniversitéParis DescartesParisFrance HPB and Liver Transplantation Unit Department of SurgeryUniversity ClinicUniversidad de NavarraNavarraSpain Institute of Health Research of Navarra(IdisNA) PamplonaSpain Department of Surgery University of VeronaVeronaItaly Department of Surgery Virginia Mason Medical CenterSeattleWAUSA Department of Surgery University of California San FranciscoSan FranciscoCAUSA Department of Hepato-Pancreato-Biliary Surgery Moscow Clinical Research CentreMoscowRussia

Background:It is well known that laparoscopic liver surgery can offer advantages over open liver surgery in selected ***,what type of procedures can benefit most from a laparoscopic approach has been investigated poorly thus *** aim of this study is thus to define the extent of advantages of laparoscopic over open liver surgery for lesions in the anterolateral(AL)and posterosuperior(PS)***:In this international multicentre retrospective cohort study,laparoscopic and open minor liver resections for lesions in the AL and PS segments were compared after propensity score *** differential benefit of laparoscopy over open liver surgery,calculated using bootstrap sampling,was compared between AL and PS resections and expressed as a Delta of the ***:After matching,3,040 AL and 2,336 PS resections were compared,encompassing open and laparoscopic procedures in a 1:1 *** and PS laparoscopic liver resections were more advantageous in comparison to open in terms of blood loss,transfusion rate,complications,and length of ***,AL resections benefitted more from laparoscopy than PS in terms of overall and severe complications(D-difference were 4.8%,P=0.046 and 3%,P=0.046)and blood loss(D-difference was 195 mL,P<0.001).Similar results were observed in the subset for high-volume centres,while in recent years no significant differences were found in the differential benefit between AL and PS ***:The advantage of laparoscopic over open liver surgery is greater in the AL segments than in the PS segments.

关键词： Liver neoplasms hepatectomy laparoscopic liver resection open liver resection

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Performance and Optimization for a Ground-Coupled Liquid Loop Heat Recovery Ventilation System

引用

Journal of Donghua University(English Edition) 2007年第6期24卷 749-755页

作者：周亚素 Per FAHLEN Torbjrn LINDHOLM Department of Building Environment and Equipment Engineering Donghua University Department of Building Services Engineering Chalmers University of TechnologySE-412 96GothenburgSweden

Ground-coupled heat pumps(GCHP)are commonly used in residential heating *** mitigate the boreholes temperature dropping with operating time,a new exhaust-air recharging system is *** new recharging system can be used in three operational *** this paper,a ground-coupled heat recovery ventilation(HRV)model is discussed.A thermal model is set up to find the optimal brine flow rate and heat transfer allocation ratio between exhaust and supply coils for maximum heat recovery *** to the conventional liquid-loop HRV systems,the brine temperature entering the exhaust coil never goes blow zero(0℃),and hence defrosting is needless in the ground-coupled HRV *** can make the ground-coupled HRV system over 20% more efficient than a conventional HRV system at low outdoor temperatures.

关键词： a ground-coupled HRV system thermal model heat recovery efficiency coils allocation ratio brine flow rate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Stability of Finite Difference Discretizations of Multi-Physics Interface Conditions

引用

Communications in Computational Physics 2013年第2期13卷 386-410页

作者： Björn Sjögreen Jeffrey W.Banks Center for Applied Scientific Computing Lawrence Livermore National LaboratoryLivermoreCA 94551USA

We considermulti-physics computationswhere theNavier-Stokes equations of compressible fluid flow on some parts of the computational domain are coupled to the equations of elasticity on other parts of the computational *** different subdomains are separated by well-defined *** consider time accurate computations resolving all time *** such computations,explicit time stepping is very *** address the issue of discrete interface conditions between the two domains of different physics that do not lead to instability,or to a significant reduction of the stable time step *** such interface conditions is *** discretize the problem with high order centered difference approximations with summation by parts boundary *** derive L2 stable interface conditions for the linearized one dimensional discretized ***,we generalize the interface conditions to the full non-linear equations and numerically demonstrate their stable and accurate performance on a simple model *** energy stable interface conditions derived here through symmetrization of the equations contain the interface conditions derived through normal mode analysis by Banks and Sj¨ogreen in[8]as a special case.

关键词： Fluid-structure interaction finite difference method summation by parts multiphysics interface condition

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Voles and weasels in the boreal Fennoscandian small mammal community:what happens if the least weasel disappears due to climate change?

引用

Integrative Zoology 2019年第4期14卷 327-340页

作者： Hannu YLÖNEN Marko HAAPAKOSKI Thorbjörn SIEVERT Janne SUNDELL Department of Biological and Environmental Science and Konnevesi Research Station University of JyväskyläJyväskyläFinland Lammi Biological Station University of HelsinkiLammiFinland

Climate change,habitat loss and fragmentation are major threats for populations and a challenge for individual behavior,interactions and ***-prey interactions are modified by climate *** the northern latitudes,strong seasonality is changing and the main predicted feature is shortening and instability of win*** populations in the boreal Fennoscandia exhibit multiannual *** amplitude peak numbers of voles and dramatic population lows alternate in 3-5-year cycles shortening from North to *** key factor,or driver,promoting the population crash and causing extreme extended lows,is suggested to be predation by the least *** review the arms race between prey voles and weasels through the multiannual density fluctuation,affected by climate change,and especially the changes in the duration and stability of snow *** ground-dwelling small mammals,snow provides thermoregulation and shelter for nest sites,and helps them hide from *** increases in the instability of winter forms a major challenge for species with coat color change between brown summer camouflage and white winter *** of these is the least weasel,Mustela nivalis *** vulnerability of wrong-colored weasels to predation affects vole populations and may have dramatic effects on vole *** may have cascading effects on other small rodent-predator interactions and even on plant-animal interactions and forest dynamics.

关键词： cascading effects climate change least weasel population cycles predator-prey

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Machine learning model for snow depth estimation using a multisensory ubiquitous platform

引用

Journal of Mountain Science 2022年第9期19卷 2506-2527页

作者： Sofeem NASIM Mourad OUSSALAH Björn KLÖVE Ali Torabi HAGHIGHI Department of Computer Science and Engineering University of OuluOulu 90570Finland Water Energy and Environmental EngineeringUniversity of OuluOulu 90570Finland

Snow depth estimation is an important parameter that guides several hydrological applications and climate change *** advances in remote sensing technology and enhanced satellite observations,the estimation of snow depth at local scale still requires improved accuracy and *** advances in ubiquitous and wearable technology promote new prospects in tackling this *** this paper,a wearable IoT platform that exploits pressure and acoustic sensor readings to estimate and classify snow depth classes using some machine-learning models have been put ***,the results of Random Forest classifier showed an accuracy of 94%,indicating a promising alternative in snow depth measurement compared to in situ,LiDAR,or expensive large-scale wireless sensor network,which may foster the development of further affordable ecological monitoring systems based on cheap ubiquitous sensors.

关键词： Snow depth Wearable technology Machine learning Random forest classifier

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of different forms of nitrogen addition on microbial extracellular enzyme activity in temperate grassland soil

引用

Ecological Processes 2022年第1期11卷 483-490页

作者： Lili Dong Björn Berg Weiping Gu Zhengwen Wang Tao Sun Erguna Forest-Steppe Ecotone Research Station Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Forest Sciences University of Helsinki00014 HelsinkiFinland Section of Biology University of Gävle80176 GävleSweden Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China

Background:Nitrogen(N)deposition alters litter decomposition and soil carbon(C)sequestration by influencing the microbial community and its enzyme *** atmospheric N deposition comprises of inorganic N(IN)and organic N(ON)***,most studies have focused on IN and its effect on soil C cycling,whereas the effect of ON on microbial enzyme activity is poorly *** we studied the effects of different forms of externally supplied N on soil enzyme activities related to decomposition in a temperate *** nitrate was chosen as IN source,whereas urea and glycine were chosen as ON *** ratios of IN to ON(Control,10:0,7:3,5:5,3:7,and 0:10)were mixed with equal total amounts of N and then used to fertilize the grassland soils for 6 ***:Our results show that IN deposition inhibited lignin-degrading enzyme activity,such as phenol oxidase(POX)and peroxidase(PER),which may restrain decomposition and thus induce accumulation of recalcitrant organic C in grassland *** contrast,deposition of ON and mixed ON and IN enhanced most of the C-degrading enzyme activities,which may promote the organic matter decomposition in grassland *** addition,theβ-N-acetyl-glucosaminidase(NAG)activity was remarkably stimulated by fertilization with both IN and ON,maybe because of the elevated N availability and the lack of N limitation after long-term N fertilization at the grassland ***,differences in soil pH,soil dissolved organic carbon(DOC),and microbial biomass partially explained the differential effects on soil enzyme activity under different forms of N ***:Our results emphasize the importance of organic N deposition in controlling soil processes,which are regulated by microbial enzyme activities,and may consequently change the ecological effect of N ***,more ON deposition may promote the decomposition of soil organic matter thus converting C sequestration in grassland soils into a

关键词： Inorganic N deposition Organic N deposition Soil microbial biomass Microbial enzyme activity Decomposition Grassland

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：