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Deadwood position matters:Diversity and biomass of saproxylic beetles in a temperate beech forest

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Forest Ecosystems 2024年第1期11卷 120-130页

作者： vaclav Zumr Oto Nakladal Josef Gallo JiríRemes Faculty of Forestry and Wood Sciences Czech University of Life Sciences PragueKamýck a 129Praha 6-Suchdol16500Czech Republic

Deadwood plays a key role for biodiversity in forests.A significant number of beetles from this group are currently listed as endangered in the Red *** addition to other management recommendations,there have been recent efforts to enrich stands with dead wood to promote *** important parameter for forestry enterprises is the optimization of these *** study investigated the abundance,species richness,gamma diversity,conservation value and biomass of saproxylic beetles in natural forests using window traps.A total of 89traps were used for saproxylic beetle monitoring,of which 29 were placed on lying logs,30 on snags and 30 as controls in forest stand space.A total of 35,011 beetles were recorded in 564 species(61 families).Notably,20,515 of these belong to saproxylic beetles(59%)in 311 species(55%),with 62 classified as Red-List species(20%).In the group of'all saproxylic beetles',the results indicate that a diversity and y diversity(q=0)remain consistent across various deadwood types,whileβdiversity showed significant *** differences were found in the Red-List species group,where a diversity and y diversity differed,with higher values observed in *** based total species richness of site was estimated to be 391 species,including 74 Red-Listed *** the sample coverage of the studied stand categories showed that all saproxylic species exhibit a pronounced preference for inhabiting areas featuring lying ***,Red-List species mainly inhabit snags,withβdiversity being more similar to snags and forest stand ***,both the conservation value(weighted average by conservation status)and beetle biomass are significantly highest in snags,whereas stand space shows the lowest values across all measured saproxylic beetle ***,the use of traps set on the poles in forest stand space resulted in an underestimation of the actual stand richness by 20%-25%.Our results support th

关键词： Snags Coleoptera Fagus sylvatica Unmanaged forests Red-list Coarse woody debris

Transonic Instability in Entrance Part of Mixing Chamber of High-Speed Ejector

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Journal of Thermal Science 2005年第3期14卷 258-263,271页

作者： vaclav Dvorak Pavel Safarik Technical University of Liberec Faculty of Mechanical Engineering Division of Power Engineering Halkova 6 461 17 Liberec Czech Republic Ph.DCzech Technical University in Prague Faculty of Mechanical Engineering 207- Institute of Fluid Dynamics and Power Engineering Division of Fluid Dynamics and Thermodynamics. Technicka 4 166 07 Praha 6 Czech Republic

The paper deals with experimental and numerical study of flow structure in two-dimensional model of supersonic ejector. Schlieren pictures of flow structure were taken, static pressure distributions on side wall were measured and Fluent software to calculate the flow structure in supersonic ejector was used. For certain region of back pressure ratio pb/p02 and stagnation pressure ratio of both streams p01/p02 the terminal shock wave is close to the trailing edge of the primary flow nozzle and a transonic instability occurs. The instability causes the movement of position of boundary layer separation, the structure of shock waves changes and all flow structure oscillates. The movie of these regimes during schlieren experiments was taken and relevant numerical modelling was performed.

关键词： transonic instability ejector shock waves

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沙漠战士角蜥泣血而战的御敌艺术家

环球人文地理 2024年第3期 74-81页

作者：鲨鲨 David McGowen vaclav Scott rodphotography Ted Dale qingwa Phil and Karen flickr

关键时刻能用眼睛喷出身体三分之一的血量，静止、伪装、膨胀……得克萨斯州的小小角蜥如同沙漠中的八边形战士，不舍昼夜地研究如何御敌。在长期的生存竞争中，动物们演化出了形形色色的逃生技巧。比如蟾蜍自爆求存，蚂蚁自杀式爆炸袭...

关键时刻能用眼睛喷出身体三分之一的血量，静止、伪装、膨胀……得克萨斯州的小小角蜥如同沙漠中的八边形战士，不舍昼夜地研究如何御敌。在长期的生存竞争中，动物们演化出了形形色色的逃生技巧。比如蟾蜍自爆求存，蚂蚁自杀式爆炸袭击……而最令人惊奇的，则是角蜥的喷血御敌。

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Supersonic Flow Structure in the Entrance Part of a Mixing Chamber of 2D Model Ejector

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Journal of Thermal Science 2003年第4期12卷 344-349页

作者： vaclav Dvorak Pavel Safarik Technical University in Liberec Faculty of Mechanical Engineering Department of Power Engineering Equipment. Halkova 6461 17 Liberec Czech RepublicCzech Technical University in Prague Faculty of Mechanical Engineering 207.1 Institute of Fluid Dynamics and Power Engineering Division of Fluid Dynamics and Thermodynamics. Technicka 4 166 07 Praha 6 Czech Republic

The paper deals with experimental and numerical results of investigation into supersonic and transonic flow past a two-dimensional model ejector. Results of optical measurements show a flow structure and flow parameter development in the entrance part of the mixing chamber of the ejector. Numerical results are obtained by means of both the straight solution of shock waves in supersonic flow field using classical relations of parameters of shock waves and the Fluent 6 program. Results of numerical solutions are compared with experimental pictures of flow fields. Flow structure development in the mixing chamber is analysed in detail.

关键词： supersonic ejector shock waves shear layers mixing process boundary layer separation.

Structural and photocatalytic characteristics of TiO_(2) coatings produced by various thermal spray techniques

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Journal of Advanced Ceramics 2013年第3期2卷 218-226页

作者： Pavel CTIBOR vaclav STENGL Zdenek PALA Institute of Plasma Physics ASCRv.v.i.Za Slovankou 3PragueCzech Republic Institute of Inorganic Chemistry ASCRv.v.i.Husinec-RezCzech Republic

Titanium dioxide(TiO_(2))was elaborated by four different thermal spray techniques-(i)plasma spraying using a water-stabilized torch,(ii)plasma spraying using a gas-stabilized torch,(iii)high velocity oxy-fuel gun,and(iv)oxy-acetylene *** porosity of the coatings was studied by optical microscopy,nano-structural features by scanning electron microscopy(SEM),phase composition by X-ray diffraction(XRD);the microhardness,surface roughness and wear resistance were *** diffuse reflectance was measured by ultra-violet/visible/near-infrared(UV/Vis/NIR)scanning *** kinetics of photocatalytic degradation of gaseous acetone was measured under a UV lamp with 365 nm *** all the applied spray processes,the transformation of anatase phase from the initial powders to rutile phase in the coatings *** spite of this transformation,all the coatings exhibited certain photocatalytic activity,which correlated well with their band gap energy calculated from *** the coatings offer relatively good mechanical properties and can serve as robust photocatalysts.

关键词： plasma spraying high velocity oxy-fuel(HVOF)spraying flame spraying titanium dioxide(TiO_(2)) photocatalysis band gap

Analysis of 3.4 Ah lithium-sulfur pouch cells by electrochemical impedance spectroscopy

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Journal of Energy Chemistry 2022年第9期31卷 318-325,I0009页

作者： Dominika Capkova vaclav Knap Andrea Strakova Fedorkova Daniel-Ioan Stroe Department of Physical Chemistry Pavol Jozef Safarik University in KosiceKosice 04154Slovak Republic Faculty of Electrical Engineering Czech Technical University in PraguePrague 16627Czech Republic Department of Energy Technology Aalborg UniversityAalborg East 9220Denmark

Despite great progress in lithium-sulfur(Li-S) batteries, the electrochemical reactions in the cell are not yet fully understood. Electrode processes, complex interfaces and internal resistance may be characterized by electrochemical impedance spectroscopy(EIS). EIS is a non-destructive technique and easy to apply, though there are challenges in ensuring the reproducibility of measurements and the interpretation of impedance data. Here, we present the impedance behavior of a 3.4 Ah Li-S pouch cell characterized by EIS. The impedance changes were analyzed over the entire depth-of-discharge, depth-of-charge,and at various temperatures. Based on the formation of intermediates during(dis)charging, the changes of resistances are observed. Overall, the increase in temperature causes a decrease in electrolyte viscosity,lowering the surface energy which can improve the penetration of the electrolyte into the electrode pores. Moreover, the effect of superimposed AC current during EIS measurement was analyzed, and the results show the dependence of the charge transfer resistance on superimposed AC current which was lower compared to steady-state conditions and consents with theory.

关键词： Lithium-sulfur battery Impedance Equivalent circuit Temperature dependencies Charging/discharging differences Dynamic electrochemical impedance spectroscopy

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国际盆景协会佳作选登(五)

花木盆景（下半月） 2024年第6期 64-67页

作者： [菲律宾]Charlie Lee [波兰]Piotr Tomasz Czernichowski [韩国]Park Jae Heon [墨西哥]Enrique Castano [印度尼西亚]Oka Sunarya [捷克]vaclav Novak 罗民轩不详中国台湾

国际盆景协会(Bonsai Clubs International,BCI)于1963年在美国成立,会员分布在50多个国家和地区,每年在不同的国家或地区举行大会和年展,对世界盆景文化的发展起到了重要的推动作用。2023年9月,陈昌先生成功当选BCI主席,成为BCI历史上... 详细信息

国际盆景协会(Bonsai Clubs International,BCI)于1963年在美国成立,会员分布在50多个国家和地区,每年在不同的国家或地区举行大会和年展,对世界盆景文化的发展起到了重要的推动作用。2023年9月,陈昌先生成功当选BCI主席,成为BCI历史上首位中国籍主席。本栏目由花木盆景杂志社与BCI合办,让您通过BCI之窗,领略世界各地盆景魅力。

关键词：花木盆景盆景协会中国籍 BCI

Optimized Deep Learning-Inspired Model for the Diagnosis and Prediction of COVID-19

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Computers, Materials & Continua 2021年第5期67卷 2353-2371页

作者： Sally M.Elghamrawy Aboul Ella Hassnien vaclav Snasel MISR Higher Institute for Engineering and Technology MansouraEgypt Faculty of Computers and Information Cairo UniversityCairoEgypt VSB-Technical University of Ostrava Czech Republic

Detecting COVID-19 cases as early as possible became a critical issue that must be addressed to avoid the pandemic’s additional spread and early provide the appropriate treatment to the affected *** study aimed to develop a COVID-19 diagnosis and prediction(AIMDP)model that could identify patients with COVID-19 and distinguish it from other viral pneumonia signs detected in chest computed tomography(CT)*** proposed system uses convolutional neural networks(CNNs)as a deep learning technology to process hundreds of CT chest scan images and speeds up COVID-19 case prediction to facilitate its *** employed the whale optimization algorithm(WOA)to select the most relevant patient signs.A set of experiments validated AIMDP *** demonstrated the superiority of AIMDP in terms of the area under the curve-receiver operating characteristic(AUC-ROC)curve,positive predictive value(PPV),negative predictive rate(NPR)and negative predictive value(NPV).AIMDP was applied to a dataset of hundreds of real data and CT images,and it was found to achieve 96%AUC for diagnosing COVID-19 and 98%for overall *** results showed the promising performance of AIMDP for diagnosing COVID-19 when compared to other recent diagnosing and predicting models.

关键词： Convolutional neural networks coronavirus disease 2019(COVID-19) CT chest scan imaging deep learning technique feature selection whale optimization algorithm

Sensitivity of polyphagous(Plodia interpunctella)and stenophagous(Ephestia kuehniella)storage moths to residual insecticides:effect of formulation and larval age

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Insect Science 2021年第6期28卷 1734-1744页

作者： vaclav Stejskal Jitka Stara Stano Pekar Marta Nesvorna Jan Hubert Crop Research Institute PragueCzechia Faculty of Science Department of Botany and ZoologyMasaryk UniversityBrnoCzechia Faculty of Agrobiology Food and Natural ResourcesCzech University of Life SciencesPragueCzechia

Pyralid moths,Ephestia kuehniella and Plodia interpunctella,are prevalent stored product *** insecticides are the main tool to control these moths in the *** data describing the response of these moths to insecticides are *** lethal effect of the organophosphate,pyrethroid,and halogenated-pyrrole on moths larvae were compared in laboratory *** hypothesis was that the very polyphagous ***-punctella would have generally higher insecticide tolerance than that of the stenophagous *** insecticide concentrations were applied onto the inner surface of glass tube *** larvae of 14 or 21 d old of *** and 7 or 14 d old of *** were used by *** larval mortality was checked after 24 h of *** mortality was significantly influenced by age of larvae and the groups of *** differences among the efficacies of the tested formulations with identical active compounds were found,except significant different mortality of *** on deltamethrin formulations.A comparison of analytical standards showed that *** was less susceptible to the active ingredient pirimiphos-methyl than ***,while *** was less susceptible to deltamethrin than *** differences between the two species were observed for *** therefore rejected the hypothesis that polyphagy/stenophagy can be a general predictor of insecticide tolerance in the two tested storage *** most important finding for effective use was that the young larvae of both species were more susceptible to tested insecticides than older larvae.

关键词： efficacy integrated pest management IRAC pesticides Pyralidae residual