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Journal of Environmental Sciences 2016年第6期28卷 197-203页

作者： Regina Wardzynska Beata Zaleska-chróst Department of Chemistry University of Warmia and Mazury in Olsztyn

The results of studies carried out using a computer programme simulating the coagulation of suspensions containing spherical sol particles and spherical coagulant particles are *** influence of the degree of dispersion of the system on the coagulation reaction kinetics was investigated. The obtained results of kinetic studies were tested in the light of classical Müller–Smoluchowski equations. The influence of the physical properties of the coagulant,such as size, density and mass, on the coagulation rate was tested. It was found that within the range described in this paper, the rate of the simulated coagulation process fulfils both the kinetic equation of a first-order reaction, and the kinetic equation of a second-order *** the tested range, a significant influence of the mass and size of the coagulant on the coagulation rate was ascertained. The kinetic Müller–Smoluchowski dependence is fulfilled in a broader range of the degree of dispersion, when the coagulant particle mass and the sol particle mass are equal. When the particle mass increases with an increase in the particle radius, the coagulation rate increases faster that it would result from the Müller＇s dependence.

关键词： Aggregation Computer simulation Coagulation rate Sol

The Biological Consequences of Global Change

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Integrative Zoology 2010年第2期5卷 85-86页

作者： Nils chr.STENSETH Centre for Ecological and Evolutionary Synthesis(CEES) Department of BiologyUniversity of OsloOsloNorway

ChangeClimate is currently *** changes will havea variety of effects on biological systems,at various lev-els spanning from the physiological to the ecosystem ***,among others,need to address the questionof how climate changes(and variation)affect biologicalprocess at these different levels of organization,and theyneed to do so in an integrated *** this view inmind,Integrative Zoology is pleased to present this spe-cial issue on“the biological consequences of globalchange.”This special issue is linked to a larger initiativeof the International Society of Zoological Sciences,namely,its flagship research program with the same title:the“Bio-logical Consequences of Global Change”(BCGC).Thisspecial issue is the first in a series of such issues:duringthe period 2010 to 2012 Integrative Zoology plan to pub-lish one such special issue per year.

关键词： sequences consequences Global

Reflections from the president of the International Society of Zoological Sciences:the zoology of zoonotic infectious diseases

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Integrative Zoology 2022年第2期17卷 328-329页

作者： Nils chr.STENSETH Professor of Ecology and Evolution at the Centre for Ecological and Evolutionary Synthesis(CEES) University of OsloNorway Professor of Marine Biology at the Centre for Coastal Research(CCR) University of AgderKristiansandNorway President of the International Society of Zoological Sciences

The past 2 years we now have behind us have demonstrated the importance of understanding the dynamics of zoonotic diseases in the wild and how the disease agents spill over to the human *** the end of 2021,Integrative Zoology published 2 special subsections on this topic,one of which focuses on plague—a zoonotic infectious disease which through history has ravaged the ***,caused by the bacterium Yersinia pestis,continues to cause deaths among people.I am quite confident that we will not get rid of wildlife plague,but human plague epidemics might be history in the not too distant future(Baril et al.2019;Vallès et al.2020).

关键词： population Reflections

POWER LAW NONLINEAR VISCOELASTIC CRACK-TIP FIELDS

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Acta Mechanica Solida Sinica 2003年第3期16卷 269-275页

作者： ZhangWeim‘ & chr(124) ’nI ZhangChunyuan: ZhangPing InstituteofFundamentalMechanicsandMaterialEngineering XiangtanUniversityXiangtan411105China DepartmentofArchitecturalEngineering XiangtanUniversityXiangtan411105China

The aim of this paper is to derive the power law type nonlinear viscoelastic crack-tip *** the requirement of later derivation,the HRR singular fields and the high-order asymp- totic fields are first *** they are essentially the isotropic,incompressible,power law type nonlinear elastic crack-tip fields is *** a concise review of the elasticity recov- ery correspondence principle for solving the nonlinear viscoelastic problems,the correspondence principle for solving the crack problems of power law type nonlinear viscoelastic materials under the first type boundary condition is *** solution of the crack-tip stress,strain fields for the power law type nonlinear viscoelastic materials,especially for the modified polypropylene, is obtained.

关键词： nonlinear viscoelastic elasticity recovery correspondence principle HRR singular fields crack-tip high-order asymptotic fields

Analyzing short time series data from periodically fluctuating rodent populations by thresholdmodels: A nearest block bootstrap approach

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Science China Mathematics 2009年第6期52卷 1085-1106页

作者： CHAN Kung-Sik TONG Howell STENSETH Nils chr Department of Statistics and Actuarial Science The University of IowaIowa CityIA 52242USA Department of Statistics London School of Economics & the University of Hong KongHong KongChina Centre for Ecological and Evolutionary Synthesis(CEES) Department of BiologyUniversity of OsloP.O.Box 1066 BlindernN-0316 OsloNorway

The study of the rodent fluctuations of the North was initiated in its modern form with Elton's pioneering *** scientific studies have been designed to collect yearly rodent abundance data,but the resulting time series are generally subject to at least two "problems":being short and *** explore the use of the continuous threshold autoregressive(TAR) models for analyzing such *** the simplest case,the continuous TAR models are additive autoregressive models,being piecewise linear in one lag,and linear in all other *** location of the slope change is called the threshold *** continuous TAR models for rodent abundance data can be derived from a general prey-predator model under some simplifying *** lag in which the threshold is located sheds important insights on the structure of the prey-predator *** propose to assess the uncertainty on the location of the threshold via a new bootstrap called the nearest block bootstrap(NBB) which combines the methods of moving block bootstrap and the nearest neighbor *** NBB assumes an underlying finite-order time-homogeneous Markov ***,the NBB bootstraps blocks of random block sizes,with each block being drawn from a non-parametric estimate of the future distribution given the realized past bootstrap *** illustrate the methods by simulations and on a particular rodent abundance time series from Kilpisjrvi,Northern Finland.

关键词： AIC continuous threshold autoregressive model non-nested hypotheses partial residual plots 62M10 62P10

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Rejoinder

Science China Mathematics 2009年第6期52卷 1111-1112页

作者： CHAN Kung-Sik TONG Howell STENSETH Nils chr

We are grateful to Professors Peter Hall, W.K. Li and Guodong Li for their illuminating discussions. In particular, we thank Professor Hall for pointing out his earlier joint work with

关键词： SETAR Rejoinder

Investigations on the Corrosion Behaviour and Structural Characteristics of Low Temperature Nitrided and Carburised Austenitic Stainless Steel

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材料热处理学报 2004年第5期25卷 311-315页

作者： D. Mnter H.-J. Spies H. Biermann chr. Eckstein Department of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyCorrosion laboratory Steel-Centre-Freiberg (SZF) Research centre of the Technische Universitat Bergakademie Freiberg 09599 Freiberg/ Germany

The wear resistance of austenitic stainless steels can be improved by thermo-chemical surface treatment with nitrogen and carbon. However, it is possible that the corrosion resistance will be impaired by the precipitation of chromiumnitrid or -carbide. The present contribution deals with investigations of the corrosion behaviour and structural characteristics of a low temperature nitrided and carburised austenitic stainless steel. The material investigated was AISI 316L (X2CrNiMol7-12-2) austenitic stainless steel. A commercial plasma-nitriding unit (pulsed dc) was used for the nitriding and carburising process. Additional samples were treated by the gasoxinitriding process for a comparison between plasma- and gasoxinitriding. The nitrided and carburised layer of austenitic stainless steel consists of the nitrogen or carbon S-phase (expanded austenite), respectively. X-ray diffraction investigations show the typical shift of the peaks to lower angles, indicating expansion of the fee lattice. Also the X-ray diffraction technique was employed to study the residual stresses in the nitrogen and carbon S-phase. The corrosion behaviour of surface engineered samples was investigated with electrochemical methods. Anodic potentiodynamic polarisation curves were recorded for testing the resistance against general corrosion (in H2SO4) and pitting corrosion (in NaCl).

关键词：奥氏体不锈钢腐蚀低温渗氮低温渗碳残留应力

Diversity of arbuscular mycorrhizal fungi associated with desert ephemerals growing under and beyond the canopies of Tamarisk shrubs

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Chinese Science Bulletin 2006年第A1期51卷 132-139页

作者： SHI Zhaoyong ZHANG Liyun FENG Gu chr stie Peter TIAN Changyan LI Xiaolin Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China College of Resources and Environmental Sciences China Agricultural University Beijing 100094 China Agricultural and Environmental Science Department Queen's University Belfast Belfast BT9 PX UK

arbuscular mycorrhizal (AM ) 四很普通的短暂植物种的真菌的地位， Chorispora tenella (棺罩) DC， Cerato-cephalus testiculatus (Crantz ) 贝丝， Eremopyrum 面向(L) Jaub et Spash 和在树柳属植物灌木(Tamarix spp ) 统治的一个区域成长的维朗妮卡 campy-lopoda Boiss 被调查。四 ephemerals 和他们的根围土壤的样品从在下面并且在 Tamariskshrubs 的华盖以外被收集。植物 mycorrhizal 地位和土壤 AM 真菌的孢子密度和社区结构被分析并且比较在下面并且在灌木华盖以外。在他们的相应根围土壤的 ephemerals 和孢子密度的 mycorrhizal 殖民率在灌木华盖下面是显著地更低的比在远处。在灌木(12 ) 下面的 AM 真菌的种类的数字也比在华盖(19 ) 以外低。什么时候在四 ephemerals 的根围玷污性质，被检验的、可得到的 N 和 P 和全部的 P，有机物内容，全部的盐内容和电的电导率(EC ) 都在华盖下面是更高的比在远处。相反，玷污显示出的可得到的 K 和酸碱值没有如此的趋势。上午 21 点的一个总数真菌的种类从四 ephemerals 的根围土壤被孤立。五属于 Acaulospora，到 Archaeo-spora， 13 到血管球并且二到 Paraglomus。我们得出结论 Tamarix spp 的华盖。对 ephemerals 的 AM 地位并且在 AM 真菌的社区和一些他们的根围土壤的性质上施加了一些影响。

关键词：灌木真菌短生植物树冠撑柳

Very Original Proofs of Two Famous Problems: “Are There Any Odd Perfect Numbers?” (Unsolved until to Date) and “Fermat’s Last Theorem: A New Proof of Theorem (Less than One and a Half Pages) and Its Generalization”

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Advances in Pure Mathematics 2021年第11期11卷 891-928页

作者： Demetrius chr. Poulkas Department of Mathematics Aristotle University of Thessaloniki Thessaloniki Greece School of Electrical and Computer Engineering National Technical University of Athens Athens Greece School of the Faculty of Engineering Aristotle University of Thessaloniki Thessaloniki Greece Department of Mechanical Engineering and Aeronautics Faculty of Engineering University of Patras Patra Greece

This article presents very original and relatively brief or very brief proofs about of two famous problems: 1) Are there any odd perfect numbers? and 2) “Fermat’s last theorem: A new proof of theorem and its generalization”. They are achieved with elementary mathematics. This is why these proofs can be easily understood by any mathematician or anyone who knows basic mathematics. Note that, in both problems, proof by contradiction was used as a method of proof. The first of the two problems to date has not been resolved. Its proof is completely original and was not based on the work of other researchers. On the contrary, it was based on a simple observation that all natural divisors of a positive integer appear in pairs. The aim of the first work is to solve one of the unsolved, for many years, problems of the mathematics which belong to the field of number theory. I believe that if the present proof is recognized by the mathematical community, it may signal a different way of solving unsolved problems. For the second problem, it is very important the fact that it is generalized to an arbitrarily large number of variables. This generalization is essentially a new theorem in the field of the number theory. To the classical problem, two solutions are given, which are presented in the chronological order in which they were achieved. Note that the second solution is very short and does not exceed one and a half pages. This leads me to believe that Fermat, as a great mathematician was not lying and that he had probably solved the problem, as he stated in his historic its letter, with a correspondingly brief solution. To win the bet on the question of whether Fermat was telling truth or lying, go immediately to the end of this article before the General Conclusions.

关键词： Perfect Numbers Odd Perfect Numbers Fermat’s Last Theorem Generalization of the Fermat’s Last Theorem Prime Number Problems Millennium Problems