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Dielectric Properties and the Phase Transition of Pure and Cerium Doped Calcium-Barium-Niobate

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World Journal of Condensed Matter Physics 2012年第2期2卷 80-84页

作者： Alexander Niemer Rainer Pankrath klaus betzler Manfred Burianek Manfred Muehlberg Department of Physics University of Osnabrück Osnabrück Germany Institute of Crystallography University of Cologne Cologne Germany

The complex dielectric constant of pure and cerium doped calcium-barium-niobate (CBN) was studied at frequencies 20 Hz ≤ f ≤ 1 MHz in the temperature range 300 K ≤ T ≤ 650 K and compared with the results for the well known ferroelectric relaxor strontium-barium-niobate (SBN). By the analysis of the systematically taken temperature and frequency dependent measurements of the dielectric constant the phase transition characteristic of the investigated materials was evaluated. From the results it must be assumed that CBN shows a slightly diffuse phase transition without relaxor behavior. Doping with cerium yields a definitely different phase transition characteristic with some indications for a relaxor type ferroelectric material, which are common from SBN.

关键词： 77.80.-e Ferroelectricity and Antiferroelectricity 77.80.Jk Relaxor Ferroelectrics 77.84.Ek Niobates and Tantalates 77.22.Ch Permittivity (Dielectric Function)

一种新型的硼酸盐晶体BiB_3O_6的二阶非线性光学行为的理论计算(英文)

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化学研究 2000年第2期11卷 1-4页

作者：薛冬峰 betzler klaus Hesse Hartmut Fachbereich Physik

利用化学键的观点 ,研究了一种新型硼酸盐晶体BiB3O6 的二阶非线性光学行为。计算结果表明 :该晶体确实具有很好的倍频性能。但是 ,它的性能还达不到目前实验报道的数值。从该晶体的结构特征出发 ,作者分析了所得出的结果 ,期待对该晶... 详细信息

利用化学键的观点 ,研究了一种新型硼酸盐晶体BiB3O6 的二阶非线性光学行为。计算结果表明 :该晶体确实具有很好的倍频性能。但是 ,它的性能还达不到目前实验报道的数值。从该晶体的结构特征出发 ,作者分析了所得出的结果 ,期待对该晶体性能做进一步测定。

关键词：二阶非线性光学晶体结构硼酸铋

Testing and modelling of transient adhesion phenomena in rolling-sliding contacts

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Friction 2024年第5期12卷 1016-1027页

作者： Daniel KVARDA Alexander MEIERHOFER klaus SIX Faculty of Mechanical Engineering Brno University of TechnologyBrno61669Czech Republic Virtual Vehicle Research GmbH Graz8010Austria

Transient adhesion effects in rolling–sliding contacts influence all aspects of train–track *** is of high importance specifically when these effects result in critically low adhesion,which poses a risk to traction and braking of railway *** study presents a model that can replicate the transient changes of the coefficient of adhesion with tested water and solid particle *** experimental data for the model are measured using a commercial ball-on-disc *** experimental results showed a liquid reservoir in front of the contact area that slowly reduces in *** observation was used in the modelling approach to divide the calculation into two stages where the reservoir is present and when it *** model was able to reproduce the occurrence of low adhesion region seen in experimental results with different particle concentrations.

关键词： coefficient of adhesion tribology transient effects wheel-rail contact

Book review “Wattles: Australian Acacia species around the world” by David M. Richardson, Johannes J. Le Roux and Elizabete Marchante

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Forest Ecosystems 2024年第2期11卷 140-141页

作者： klaus von Gadow Faculty of Forestry and Forest Ecology Georg-August-University GöttingenBüsgenweg 5D-37077GöttingenGermany Department of Forestry and Wood Science Faculty of AgriSciencesStellenbosch UniversityStellenbosch Private Bag X1Stellenbosch7602South Africa

In a world of Google and AI, developing an encyclopedic coverage of a theme that is of great interest to biologists, social scientists, politicians and environmental managers, is a daunting challenge. Wattles is a book that presents new knowledge, makes interesting reading, and has the potential to stimulate research in a variety of disciplines. We learn that Acacia, commonly known as the wattles or acacias, is a genus of shrubs and trees comprising 1,083 species of which 417 are known to have been introduced to areas outside their native range. We are surprised to read that Australian acacias are found almost everywhere, in virtually all terrestrial habitats, including woodlands, grasslands, alpine settings,rainforests, coastal dunes and deserts, causing major environmental and socio-economic changes in the invaded regions. Until recently, Acacia comprised a group of plant species native to Africa, South America and Australasia, but the name is now reserved for species predominantly from Australia, including some from Southeast Asia. The genus name Acacia is Neo-Latin, and refers to a preparation extracted from the leaves and fruit pods of Vachellia nilotica, the original type of the genus.

关键词： Richardson outside Latin

Learning about good nutrition with the 5-color front-of-package label"Nutri-Score":an experimental study

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Food Science and Human Wellness 2024年第3期13卷 1195-1200页

作者： Robin C.Hau klaus W.Lange University of Applied Sciences Landshut Landshut 84036Germany Faculty of Human Sciences University of RegensburgRegensburg 93040Germany

The Nutri-Score is a 5-color front-of-pack nutrition label designed to provide consumers with an easily understandable guideline to the healthiness of food *** impact that the Nutri-Score may have on consumers'choices is unclear since different experimental paradigms have found vastly different effect *** the present study,we have investigated how student participants change a hypothetical personal 1-daydietary plan after a learning phase during which they learn about the Nutri-Scores of the available food *** were instructed to compose a healthy diet plan in order that the question of whether the NutriScore would improve their ability to compose a healthy dietary plan could be investigated,independent of the question of whether they would apply this knowledge in their ordinary *** found a substantial(Cohen's d=0.86)positive impact on nutritional quality(as measured by the Nutrient Profiling System score of the Food Standards Agency)and a medium-sized(Cohen's d=0.43)reduction of energy *** content reduction was larger for participants who had initially composed plans with higher energy *** results suggest that the Nutri-Score has the potential to guide consumers to healthier food *** remains unclear,however,whether this potential will be reflected in real-life dietary choices.

关键词： Nutri-Score Front-of-package label Nudge Nutrition Health

Dieback of managed spruce stands in western Germany promotes beetle diversity

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Journal of Forestry Research 2024年第3期35卷 55-71页

作者： Eva Plath Chantal Trauth Jan Gerhards Laura Griebel klaus Fischer Department Biology Institute of Integrated Natural SciencesKoblenz-Landau University56070 KoblenzGermany

Biodiversity loss is a significant problem at a global scale and may be amplified by climate *** recent years,coniferous forests have had substantial die-back across Europe due to drought and subsequent bark-beetle *** many studies on the consequences of disturbance and subsequent management have focused on natural stands,management implications for managed spruce stands are not well understood,even though such stands are widespread throughout *** this study,beetle taxonomy,conservation value,and community com-position are compared among spruce plantations and four post-disturbance management approaches:standing dead-wood,lying deadwood,clear cuts,and long-term *** and community composition differed significantly among management categories,while different beetle fami-lies responded *** spruce stands harbored the lowest beetle diversity while the highest taxonomic diver-sity and conservation value was on clear cuts and stands with lying or standing *** proportion of forest specialists was highest in successional *** summary,different forest management categories harbored distinct beetle communities at the family-,species-,and ecological guild ***,post-disturbance management should consider the landscape scale and include different management *** enhances landscape heterogeneity and thus overall biodiversity but could also mitigate negative impacts of natural disturbances on ecosystem services.

关键词： Bark-beetle outbreak Forest dieback Spruce Deadwood Nature conservation Beetle biodiversity-Coleoptera Coniferous forests

An explainable AI framework for robust and transparent data-driven wind turbine power curve models

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Energy and AI 2024年第1期15卷 312-327页

作者： Simon Letzgus klaus-Robert Müller Machine Learning Group Technische Universitβe BerlinStraβe des 17.Juni 135Berlin10623Germany Berlin Institute for the Foundations of Learning and Data Berlin10587Germany Department of Artificial Intelligence Korea UniversitySeoul136-713South Korea Max Planck Institute for Informatics Saarbrücken66123Germany

In recent years,increasingly complex machine learning methods have become state-of-the-art in modelling wind turbine power curves based on operational *** these methods often exhibit superior performance on test sets,they face criticism due to a perceived lack of transparency and concerns about their robustness in dynamic,non-stationary environments encountered by wind *** this work,we address these issues and present a framework that leverages explainable artificial intelligence methods to gain systematic insights into data-driven power curve *** its core,we propose a metric to quantify how well a learned model strategy aligns with the underlying physical principles of the *** novel tool enables model validation beyond the conventional error metrics in an automated *** demonstrate,for instance,its capacity as an indicator for model generalization even when limited data is ***,it facilitates understanding how decisions made during the machine learning development process,such as data selection,pre-processing,or training parameters,affect learned *** a result,we obtain physically more reasonable models,a prerequisite not only for robustness but also for meaningful insights into turbine operation by domain *** latter,we illustrate in the context of wind turbine performance *** summary,the framework aims to guide researchers and practitioners alike toward a more informed selection and utilization of data-driven wind turbine power curve models.

关键词： Explainable AI(XAI) Machine learning Wind energy Wind turbine power curve SCADA Condition monitoring

Boosting liver regeneration: kinase inhibitor as a new tool to prevent liver failure

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Signal Transduction and Targeted Therapy 2024年第8期9卷 3145-3146页

作者： Anna Sichler Norbert Huser klaus-Peter Janssen Department of Surgery School of Medicine and HealthTechnical University of MunichMunichGermany

In a recent manuscript in Cell,a first-in-class small molecule inhibitor of the kinase MKK4(mitogen-activated protein kinase kinase 4)was described that greatly enhances liver regeneration after partial hepatectomy in animal models,with an excellent safety profile in humans.1 The findings of Zwirner et *** promise to alter the clinical management of liver failure in critically ill patients.

关键词： liver al. clinical

Food intolerance and the few-foods(or oligoantigenic)diet in children with attention-deficit hyperactivity disorder

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Food Science and Human Wellness 2024年第4期13卷 1729-1738页

作者： klaus W.Lange Andreas Reissmann Yukiko Nakamura Katharina M.Lange Faculty of Human Sciences University of RegensburgRegensburg 93040Germany Department of Psychology University of BathBath BA27AYUnited Kingdom

The hypothesis that some children with attention-deficit hyperactivity disorder(ADHD)may show sensitivity or allergic reactions to various food items has led to the development of the the few-foods(or oligoantigenic)*** rationale of the diet is to eliminate certain foods from the diet in order to exclude potential allergens contained either naturally in food or in artificial ingredients with allergenic *** oligoantigenic diet attempts to identify individual foods to which a person might be ***,ADHD symptoms are monitored while multiple foods are excluded from the ***,if symptoms remit,foods are re-introduced,while observing the individual for the return of *** advantage of the oligoantigenic diet is that it can be tailored to the individual.A growing body of evidence suggests that behavioral symptoms of subgroups of children with ADHD may benefit from the elimination of certain *** effect sizes of an oligoantigenic diet regarding improvement of ADHD symptoms have been found to be medium to *** evidence suggests that the investigation of the role of food hypersensitivities in ADHD is a promising avenue worthy of further *** large-scale,randomized controlled studies including assessment of long-term outcome are therefore warranted.

关键词： Attention-deficit hyperactivity disorder Food intolerance Few-foods diet Etiology Treatment