检索结果-南通市图书馆

Determination of the sensible heat effectiveness and pressure loss of a rotary regenerative heat exchanger using CFD

引用

Building Simulation 2023年第6期16卷 869-887页

作者： vladimír Zmrhal petr Zelenský Jindřich Boháč Martin Barták Miroslav Kučera Roman vavřička Faculty of Mechanical Engineering Department of Environmental EngineeringCzech Technical University in PragueTechnická416000Prague 6Czech Republic

The paper presents a new method to determine the sensible effectiveness and pressure loss of rotary regenerative heat exchangers using computational fluid dynamics(CFD).It is based on CFD simulations of a single thermal wheel microchannel with a small cross-sectional area and thin walls,with cyclic inlet and outlet boundary *** unique measurement set-ups were designed and built for the experimental measurement of the heat exchanger *** different types of thermal wheels were manufactured,measured,and simulated in ANSYS *** wheels achieve an effectiveness greater than 73%under certain(air flow)conditions,which is the minimum effectiveness required by Ecodesign(in the EU).For the examined exchangers,the effectiveness ranges from 66.5%to 83.3%,depending on the boundary conditions and geometric parameters of the *** highest sensible effectiveness is achieved by heat exchangers with the largest heat exchange surface Ac;on the other hand,these wheels have the largest pressure *** paper discusses the use of a simplifiedε-NTU correlation model for the HvAC systems(typically C*=1).The correlation model and CFD results were compared and found to be different from each *** results of the CFD simulation were compared with measurements to prove that the proposed simulation method can predict the behaviour of the real heat exchanger as a *** was demonstrated that the sensible effectiveness and pressure loss of the rotary heat exchanger predicted by the CFD simulations correspond well to the measured values within the measurement uncertainty±1.3%.The proposed method can be used for the comparison of different rotary regenerative heat exchangers before their manufacturing and for verification that they meet the EU Ecodesign requirements set by the current *** reduces the cost of the initial optimisation and testing of new designs.

关键词： rotary heat exchanger heat wheel microchannel heat recovery sensible effectiveness pressureloss computer fluid dynamics experiment

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

Processing and Unification of Environmental Noise Data from Road Traffic with Spatial Dimension Collected through Mobile Phones

引用

Journal of Geoscience and Environment Protection 2016年第13期4卷 1-26页

作者： petr Duda Laboratory on Geoinformatics and Cartography Masaryk University Brno Czech Republic

Noise measurement using mobile phones is now developed very well. While there are some good applications for the measurement of noise from road traffic, thus on processing of measured data is only paid a very little attention. The data, however, are burdened by specific errors and for further work with them it is necessary to adjust and determine their uncertainty. One of the biggest problems is inaccuracy in position versus the noise source and the shortest length of measurement that can be regarded as representative. Imprecision in terms of location can be determined by calculating the variance of possible distance from the noise source, which for measurement of traffic noise requires a map-matching data points both transverse to the street (sidewalk) network and in the longwise direction. During typical urban measurements, this error can even reach 7 - 10 dB. Three basic types of algorithms for the calculation of uncertainty and positional correction based on the type of input and output data (raster, vector, vector-oriented) were tested. Uncertainty in the variability of the measurement data is necessary to determine from the number of passing vehicles per time unit. The presented solutions are implemented in the Mobile Noise system.

关键词： Measurement Uncertainty Environmental Noise Mobile Phone Citizen Science Noise Mapping

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

Biotechnological preparation of chicken skin gelatine using factorial design of experiments

引用

Food Bioscience 2022年第3期47卷 898-907页

作者： petr Mrázek Robert Gál Pavel Mokrejš Jana Orsavová Dagmar Janáčová Tomas Bata University in Zlín Department of Polymer EngineeringVavrečkova 275760 01ZlínCzech Republic Tomas Bata University in Zlín Department of Food TechnologyMostní 5139760 01ZlínCzech Republic Tomas Bata University in Zlín Language CentreŠtefánikova 5670760 01ZlínCzech Republic Tomas Bata University in Zlín Department of Automation and Control EngineeringNad Stráněmi 4511760 01ZlínCzech Republic

Poultry meat production steadily increases and its by-products including legs or skins may be further utilized to prepare gelatine,generally by using alkali or acid *** they are toxic,different methods are desirable,*** proteolytic *** enzymes is beneficial as they shorten processing time and reduce the required water *** conditions(the enzyme amount during the pre-treatment,first and second extraction temperature and time)of the process may influence gelatine quality and its *** this study,gelatines were prepared from chicken skin at different conditions in the series of combined factorial design of *** significance of the influence of the conditions on the quality(gel strength,viscosity,melting and gelling point)and yield of chicken skin gelatine(CSG)was *** highest yield(31.5%)was obtained at the conditions of the enzyme amount of 0.8%,first extraction temperature 80℃ and time 30 min,second extraction temperature 90℃ and time 60 ***,the highest CSG quality of gel strength(190 Bloom),viscosity(4.06 mPas),melting point(38.3℃)and gelling point(20.5℃)was obtained at the conditions of 0.2%/50℃/30 min in the first extraction.

关键词： Collagen Chicken skin Enzyme pre-treatment Gelatine Gelling properties

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

Warming and altered precipitation rarely alter N addition effects on soil greenhouse gas fluxes:a meta-analysis

引用

Ecological Processes 2023年第1期12卷 778-790页

作者： Xinyu Wei Fuzhong Wu Koenraad van Meerbeek Ellen Desie Xiangyin Ni Kai Yue petr Heděnec Jing Yang Nannan An Key Laboratory of Humid Subtropical Eco-Geographical Processes of Ministry of Education School of Geographical SciencesFujian Normal UniversityFunan Road 8Shangjie TownMinhou CountyFuzhou 350007FujianChina Department of Earth and Environmental Sciences KU LeuvenCelestijnenlaan 200E3001 LouvainBelgium Department of Earth and Environmental Sciences KU Leuven Campus GeelKleinhoefstraat 42440 GeelBelgium Institute of Tropical Biodiversity and Sustainable Development University Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia

Background Changes in soil greenhouse gas(GHG)fluxes caused by nitrogen(N)addition are considered as the key factors contributing to global climate change(global warming and altered precipitation regimes),which in turn alters the feedback between N addition and soil GHG ***,the effects of N addition on soil GHG emissions under climate change are highly variable and context-dependent,so that further syntheses are ***,a meta-analysis of the interactive effects of N addition and climate change(warming and altered precipitation)on the fluxes of three main soil GHGs[carbon dioxide(CO_(2)),methane(CH_(4)),and nitrous oxide(N_(2)O)]was conducted by synthesizing 2103 observations retrieved from 57 peer-reviewed articles on multiple terrestrial ecosystems *** The interactive effects of N addition and climate change on GHG fluxes were generally *** combination of N addition and warming or altered precipitation increased N_(2)O emissions significantly while it had minimal effects on CO_(2)emissions and CH_(4)uptake,and the effects on CH_(4)emissions could not be ***,the magnitude of the combined effects did not differ significantly from the effects of N addition ***,the combined effects on CO_(2)and CH_(4)varied among ecosystem types due to differences in soil moisture,which was in contrast to the soil N_(2)O emission *** soil GHG flux responses to combined N addition and climate change also varied among different climatic conditions and experimental *** Overall,our findings indicate that the effects of N addition and climate change on soil GHG fluxes were relatively independent,*** effects of N addition and climate change were equal to or not significantly different from the sum of their respective individual *** effects of N addition on soil GHG fluxes influence the feedbacks between climate change and soil GHG fluxes.

关键词： N addition Warming Altered precipitation Global change CO_(2) emission CH_(4) uptake N_(2)O emission

来源：

维普期刊数据库

同方期刊数据库

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

Changes in the adult sex ratio of six duck species breeding populations over two decades

引用

Avian Research 2024年第2期15卷 202-210页

作者： Monika Homolkova petr Musil Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova Sarka Neuzilova Jan Zouhar Department of Ecology Faculty of Environmental SciencesCzech University of Life Sciences PragueKamýcka 129CZ-16521Prague–SuchdolCzech Republic Department of Terrestrial Ecology Norwegian Institute for Nature Research(NINA)PO Box 5685 TorgardenTrondheimN-7485Norway Department of Econometrics Faculty of Informatics and StatisticsUniversity of Economicsnam.W.Churchilla 4CZ-13067Prague 3Czech Republic

Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered *** with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction *** this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard Netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in South Bohemia,Czechia,between 2004 and *** evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the NAO index(North Atlantic Oscillation index)on them,indicating climate conditions in *** determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and *** the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early ***,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population.

关键词： Adult sex ratio Breeding population Population dynamics Red-listed species Waterfowl Winter weather conditions

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

High-speed performance self-powered short wave ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)

引用

Journal of Semiconductors 2024年第4期45卷 56-62页

作者： Aleksei Almaev Alexander Tsymbalov Bogdan Kushnarev vladimir Nikolaev Alexei Pechnikov Mikhail Scheglov Andrei Chikiryaka petr Korusenko Research and Development Center for Advanced Technologies in Microelectronics National Research Tomsk State UniversityTomsk 634050Russia Fokon LLC Kaluga 248035Russia Department of Semiconductor Electronics and Physics of Semiconductors National University of Science and Technology MISISMoscow 119049Russia Perfect Crystals LLC Saint Petersburg 194223Russia Department of Solid-State Electronics Saint Petersburg State UniversitySaint Petersburg 199034Russia Department of Physics Omsk State Technical UniversityOmsk 644050Russia

High-speed solar-blind short wavelength ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)layers with Pt contacts were demonstrated and their properties were studied in ***κ(ε)-Ga_(2)O_(3)layers were deposited by the halide vapor phase epitaxy on patterned GaN templates with sapphire *** spectral dependencies of the photoelectric properties of struc-tures were analyzed in the wavelength interval 200-370 *** maximum photo to dark current ratio,responsivity,detectiv-ity and external quantum efficiency of structures were determined as:180.86 ***.,3.57 A/W,1.78×10^(12) Hz^(0.5)∙cm·W^(-1) and 2193.6%,respectively,at a wavelength of 200 nm and an applied voltage of 1 *** enhancement of the photoresponse was caused by the decrease in the Schottky barrier at the Pt/κ(ε)-Ga_(2)O_(3)interface under ultraviolet *** detectors demon-strated could functionalize in self-powered mode due to built-in electric field at the Pt/κ(ε)-Ga_(2)O_(3)*** responsivity and external quantum efficiency of the structures at a wavelength of 254 nm and zero applied voltage were 0.9 mA/W and 0.46%,*** rise and decay times in self-powered mode did not exceed 100 ms.

关键词： κ(ε)-gallium oxide solar-blind shortwave ultraviolet radiation detectors self-powered operation mode

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

Cadaverine and putrescine exposure influence carbon and nitrogen cycling genes in water and sediment of the Yellow River

引用

Journal of Environmental Sciences 2024年第8期142卷 236-247页

作者： Wanghong Su Qiaoling Yu Jiawei Yang Qian Han Sijie Wang petr Hedenec Xiaochen Wang Ruijun Wan-Yan Huan Li School of Public Health Lanzhou UniversityLanzhou 730000China 2 Institute for Tropical Biodiversity and Sustainable DevelopmentUniversity Malaysia Terengganu21030Kuala NerusTerengganuMalaysia State Key Laboratory of Grassland Agro-ecosystems Center for Grassland MicrobiomeCollege of pastoral agriculture science and technology Lanzhou UniversityLanzhou 730000China

The response patterns of microbial functional genes involved in biogeochemical cycles to cadaver decay is a central topic of recent environmental ***,the response mechanisms and pathways of the functional genes associated with the carbon(C)and nitrogen(N)cycling to cadaveric substances such as cadaverine and putrescine remain *** study explored the variation of functional genes associated with C fixation,C degradation and N cycling and their influencing factors under cadaverine,putrescine and mixed *** results showed only putrescine significantly increased the alpha diversity of C fixation genes,while reducing the alpha diversity of N cycling genes in *** the C cycling,the mixed treatment significantly decreased the total abundance of reductive acetyl-CoA pathway genes(i.e.,acsB and acsE)and lig gene linked to lignin degradation in water,while only significantly increasing the hydroxypropionate-hydroxybutylate cycle(i.e.,accA)gene abundance in *** the N cycling,mixed treatment significantly decreased the abundance of the nitrification(i.e.,amoB),denitrification(i.e.,nirS3)genes in water and the assimilation pathway gene(i.e.,gdhA)in *** factors(i.e.,total carbon and total nitrogen)were all negatively associated with the genes of C and N ***,cadaverine and putrescine exposure may inhibit the pathway in C fixation and N cycling,while promoting C *** findings can offer some new insight for the management of amine pollution caused by animal cadavers.

关键词： Carbon cycling Nitrogen cycling Cadaverine Putrescine Pollution management

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

Single balloon enteroscopy for endoscopic retrograde cholangiography in patients with Roux-en-Y hepaticojejuno anastomosis

引用

World Journal of Gastroenterology 2013年第44期19卷 8047-8055页

作者： Bohuslav Kianika Jan Lata Ivo Novotny petr Dítě Jirí vaníek 2nd Clinic of Internal Medicine Department of Gastroenterology St. Anne’s University Hospital Brno 656 91 Brno Czech Republic University of Ostrava Faculty of Medicine 703 00 Ostrava Czech Republic Department of Gastroenterology Masaryk Memorial Cancer Institute 602 00 Brno Czech Republic Academic Centre of Digestive Oncology Faculty of Medicine University of Ostrava 703 00 Ostrava Czech Republic Department of Diagnostic Imaging and International Clinical Research Center (ICRC) St. Anne’s University Hospital Brno 656 91 Brno Czech Republic

AIM:To evaluate single balloon enteroscopy in diagnostic and therapeutic endoscopic retrograde cholangiography(ERC)in patients with Roux-en-Y hepaticojejunoanastomosis(HJA).METHODS:The study took place from January 2009to December 2011 and we retrospectively assessed 15patients with Roux-en-Y HJA who had signs of biliary *** total,23 ERC procedures were performed in these patients and a single balloon videoen-teroscope(Olympus SIF Q 180)was used in all of the cases.A transparent overtube was drawn over the videoenteroscope and it freely moved on the working part of the *** distal end was equipped with a silicone balloon that was inflated by air from an external pump at a pressure of≤5.4 *** technical limitations or rather the parameters of the single balloon enteroscope(working length-200 cm,diameter of the working channel-2.8 mm,absence of Albarran bridge)showed the need for special endoscopic ***:Cannulation success was reached in diagnostic ERC in 12 of 15 *** findings were normal in 1 of 12 *** in the remaining 11 patients showed some pathological *** of these(cystic bile duct dilation)was subsequently resolved *** treatment was initialized in the remaining 10 patients(5 with HJA stenosis,2 with choledocholithiasis,and 3 with both).This treatment was successful in 9 of 10 *** endoscopic therapeutic procedures included:balloon dilatation of HJA stenosis-11 times(7 patients);choledocholitiasis extraction-five times(5 patients);biliary plastic stent placement-six times(4 patients);and removal of biliary stents placed by us-six times(4 patients).The mean time of performing a single ERC was 72 *** longest procedure took 110 min and the shortest took34 *** shows that it is necessary to allow for more time in individual ***,these procedures require the presence of an *** did not observe any complications in these 15 ***

关键词： Single balloon enteroscopy Endoscopic retrograde cholangiography Roux-Y hepaticojejunoanastomosis Endoscopic diagnosis Endoscopic treatment

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

Multiple haploids, triploids, and tetraploids found in modern-day “living fossil” Ginkgo biloba

引用

Horticulture Research 2018年第1期5卷 190-201页

作者： petrŠmarda Lucie Horová Ondřej Knápek Heidi Dieck Martin Dieck Katarína Ražná Pavel Hrubík Laszlo Orlóci Laszlo Papp Kristýna veselá Pavel veselý petr Bureš Department of Botany and Zoology Masaryk UniversityKoltlářská2CZ-61137BrnoCzech Republic Herrenkamper Gärten Herrenkamp 1DE-27254SiedenburgGermany Department of Genetics and Plant Breeding Slovak University of Agriculture in NitraTr.A.Hlinku 294976NitraSlovakia Slovak University of Agriculture in Nitra Faculty of Horticulture and Landscape EngineeringDunajská1694911NitraSlovakia Botanical Garden of Eötvös University Illés utca 25BudapestHungary

Ginkgo biloba,the last extant representative of a lineage of Mesozoic gymnosperms,is one of the few seed plants with an exceptionally long(~300 Myr)evolutionary history free of genome-wide duplications(polyploidy).Despite this genome conservatism,we have recently found a viable spontaneous tetraploid Ginkgo sapling during routine screening of several plants,demonstrating that natural polyploidy is possible in *** we provide a much wider flow cytometry survey of ploidy in some European Ginkgo collections,and own seedlings(>2200 individuals and~200 cultivars).We found a surprisingly high level of ploidy variation in modern-day Ginkgo and documented altogether 13 haploid,3 triploid,and 10 tetraploid Ginkgo plants or cultivars,most of them being morphologically distinct from common *** frequently produced polyploid(dihaploid)buds or *** showed some genome size *** surveyed plants provide a unique resource for future Ginkgo research and breeding,and they might be used to accelerate the modern diversification of this nearly extinct plant lineage.

关键词： routine breeding spite

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

The 3’-untranslated region contributes to the pregnane X receptor(PXR) expression downregulation by PXR ligands and up-regulation by glucocorticoids

引用

Acta Pharmaceutica Sinica B 2020年第1期10卷 136-152页

作者： Tomas Smutny Jan Dusek Lucie Hyrsova Jana Nekvindova Alzbeta Horvatova Stanislav Micuda Sabine Gerbal-Chaloin petr Pavek Department of Pharmacology and Toxicology Faculty of Pharmacy in Hradec KraloveCharles UniversityHradec Kralove CZ-50005Czech Republic Institute of Clinical Biochemistry and Diagnostics University Hospital Hradec KraloveHradec Kralove CZ-50005Czech Republic Department of Pharmacology Faculty of Medicine in Hradec KraloveCharles UniversityHradec Kralove CZ-50003Czech Republic IRMB INSERMUniversity MontpellierMontpellierFrance

Pregnane X receptor(PXR)is the major regulator of xenobiotic *** itself is controlled by various signaling molecules including ***,negative feed-back regulation has been proposed at the transcriptional *** examined the involvement of the 3’-untranslated region(3’-UTR)of NR1I2 mRNA and microRNAs in PXR-and glucocorticoid receptor(GR)-mediated regulation of NR1I2 gene *** ligands were found to significantly downregulate NR1I2 mRNA expression in a set of 14 human hepatocyte ***,PXR was downregulated by PCN in the C57/BL6 mice *** mechanistic studies with the full-length 3’-UTR cloned into luciferase reporter or expression vectors,we showed that the 3’-UTR reduces PXR *** the miRNAs tested,miR-18a-5p inhibited both NR 112 expression and CYP3A4 gene ***,we observed significant upregulation of miR-18a-5p expression 6 h after treatment with the PXR ligand rifampicin,which indicates a putative mechanism underlying NR1I2 negative feed-back regulation in hepatic ***,glucocorticoids upregulated NR1I2 expression not only through the promoter region but also via 3’-UTR regulation,which likely involves downregulation of *** conclude that miR-18a-5p is involved in the down-regulation of NR1I2expression by its ligands and in the upregulation of NR1I2 mRNA expression by glucocorticoids in hepatic cells.

关键词： Gene expression MicroRNA Glucocorticoid Regulation Pregnane X receptor Cytochrome P4503A4

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：