检索结果-南通市图书馆

Acta Mechanica Sinica 2002年第3期18卷 235-243页

作者：方红卫 wolfgang Rodi Department of Hydraulic Engineering Tsinghua University Beijing China 100084 Institute for Hydromechanics University of Karlsruhe Karlsruhe 76128 Germany

The calculation of flow and sediment transport is one of the most important tasks in river engineering. The task is particularly difficult because a number of complex physical phenomena should be accounted for more realistically in a model with a predictive power. Three-dimensional calculations of river flow and suspended sediment transport are performed in this paper with application in the Three Gorges Reservoir in the Yangtze River. A period of 76 years after the dam is built is simulated and the results are compared with laboratory measurements obtained by Tsinghua University whereby the model is verified and calibrated. Generally speaking, the calculated results agree well with the experiments, demonstrating that the present model can be used for flow and sediment transport prediction in rivers.

关键词： three-dimensional mathematical model sediment transport Three Gorges Project (TGP)

The Austrian node of the natural resources satellite remote sensing cloud service platform:examples of Sino-Austrian cooperation

在线全文

学校读者我要写书评

暂无评论

Geo-Spatial Information Science 2021年第1期24卷 145-151,I0015页

作者： wolfgang Kainz Xinming Tang Yucai Xue Department of Geography and Regional Research University of ViennaViennaAustria Land Satellite Remote Sensing Application Center Ministry of Natural Resources of the Peoples Republic of ChinaBeijingChina

The Austrian node of the Natural Resources Satellite Remote Sensing Cloud Service Platform was established in 2016 through a cooperation agreement between the Land Satellite Remote Sensing Application Center(LASAC),Ministry of Natural Resources of the Peoples Republic of China and the University of Vienna,*** this agreement panchromatic and multi-spectral data of the Chinese ZY-3 satellite are pushed to the server at the University of Vienna for use in education and *** far,nearly 500 GB of data have been uploaded to the *** technical note briefly introduces the ZY-3 system and illustrates the implementation of the agreement by the first China-Sat Workshop and several case *** of them are already completed,others are still *** include a geometric accuracy validation of ZY-3 data,an animated visualization of image quick views on a spherical display to demonstrate the time series of the image coverage for Austria and Laos,and the use of ZY-3 data to study the spread of bark beetle in the province of Lower *** accuracy study of DTMs from ZY-3 stereo data,as well as a land cover analysis and comparison of Austria with ZY-3 and other sensors are still ongoing.

关键词： Remote sensing geographic information systems ZY-3 satellite hyperglobe Land Satellite Remote Sensing Application Center(LASAC)

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

德国南部钻石城太空送来的七万吨礼物

环球人文地理 2024年第3期 96-103页

作者：袁莘捷 lebaer wolfgang Ralf ArTo konrad filbert Andrey＿Lobachev Sina Ettmer flickr

钻石受到无数人追捧，其高昂的价格也让人望而却步。让人意外的是，在德国巴伐利亚州的西部山区，人们竟用七万吨钻石，建造了一座闪闪发光的钻石城。诺德林根是一座中世纪小镇，距今已有上千年历史。这里四面都有围墙，是德国目前仅有...

钻石受到无数人追捧，其高昂的价格也让人望而却步。让人意外的是，在德国巴伐利亚州的西部山区，人们竟用七万吨钻石，建造了一座闪闪发光的钻石城。诺德林根是一座中世纪小镇，距今已有上千年历史。这里四面都有围墙，是德国目前仅有的三座完全被城墙环绕的城市之一。小镇曾经安宁祥和，也曾经饱经硝烟，而许多建筑，甚至差点毁于一场大火。

关键词：

Mixed Phase Anatase/rutile Titanium Dioxide Nanotubes for Enhanced Photocatalytic Degradation of Methylene-blue

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nano-Micro Letters 2011年第4期3卷 236-241页

作者： Mario Boehme wolfgang Ensinger Department of Materials Science Darmstadt University of Technology

Titanium dioxide Nanotubes(TNTs) prepared by electroless deposition have been annealed at air ambient and low temperature. As a result, the anatase/rutile phase composition of the TNTs can be tailored to the needs of later applications. Nanotubes with anatase/rutile mixed phase ratio of 4:1 have been produced in this report and further examined for their photocatalytical behavior. The photocatalytical properties of the TNTs have been observed by degradation of methylene-blue in aqueous solution under low power UV-light irradiation. The results shown in this report are based on the synergetic effect between rutile and anatase,which results in the mixed phase TiO 2 nanotubes having enhanced photocatalytical properties.

关键词： Electroless deposition Degussa P25 Nanotubes Titanium dioxide Anatase

Scale up of reactors for carbon dioxide reduction

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2023年第1期17卷 116-122页

作者： Andrew Nattestad Klaudia wagner Gordon G.Wallace Intelligent Polymer Research Institute and ARC Centre of Excellence for Electromaterials Science University of WollongongWollongong NSW 2522Australia School of Chemistry Monash UniversityClayton VIC 3800Australia

In recent times there has been a great deal of interest in the conversion of carbon dioxide into more useful chemical *** the other hand,the translation of these developments in electrochemical reduction of carbon dioxide from the laboratory bench to practical scale remains an underexplored *** we examine some of the major challenges,demonstrating some promising strategies towards such scale-up,including increased electrode area and stacking of electrode pairs in different *** observed that increasing the electrode area from 1 to 10 cm^(2) led to only a 4%drop in current density,with similarly small penalties realised when stacking sub-cells together.

关键词： CO_(2)reduction electrochemical cell electrosynthesis upscaling

Cross Correlators and Galilean Invariance in Fluctuating Ideal Gas Lattice Boltzmann Simulations

在线全文

学校读者我要写书评

暂无评论

Communications in Computational Physics 2011年第5期9卷 1315-1322页

作者： Goetz Kaehler Alexander wagner Department of Physics North Dakota State UniversityFargoND 58108USA

We analyze the Lattice Boltzmann method for the simulation of fluctuating hydrodynamics by Adhikari et al.[***.,71(2005),473-479]and find that it shows excellent agreement with theory even for small wavelengths as long as a stationary system is *** is in contrast to other finite difference and older lattice Boltzmann implementations that show convergence only in the limit of large *** particular cross correlators vanish to less than 0.5%.For larger mean velocities,however,Galilean invariance violations manifest themselves.

关键词： Lattice Boltzmann fluctuations Galilean invariance

Empirical likelihood-based dimension reduction inference for linear error-in-responses models with validation study

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

Science China Mathematics 2004年第6期47卷 921-939页

作者： Wang Qihua Hardie wolfgang Academy of Mathematics and System Sciences Chinese Academy of SciencesBeijing 100080China Heilongjiang University Harbin 150080China Center for Applied Statistics and Economics Humboldt-Universitat zu Berlin10178 BerlinGermany

In this paper, linear errors-in-response models are considered in the presence of validation data on the responses. A semiparametric dimension reduction technique is employed to define an estimator of β with asymptotic normality, the estimated empirical loglikelihoods and the adjusted empirical loglikelihoods for the vector of regression coefficients and linear combinations of the regression coefficients, respectively. The estimated empirical log-likelihoods are shown to be asymptotically distributed as weighted sums of independent X 2 1 and the adjusted empirical loglikelihoods are proved to be asymptotically distributed as standard chi-squares, respectively.

关键词： confidence intervals error-in-response validation data

Seasonal size-segregated PM10 and PAH concentrations in a rural area of sugarcane agriculture versus a coastal urban area in Southeastern Florida, USA

在线全文

学校读者我要写书评

暂无评论

Particuology 2016年第5期14卷 52-59页

作者： Orhan Sevimoglu wolfgang F. Rogge Department of Civil and Environmental Engineering Florida International University 10555 W. Flagier Street Miami FL 33174 USA School of Engineering and Sierra Nevada Research Institute University of California at Merced 5200 North Lake Road Merced CA 95343 USA

Airborne particulate matter （PM） is of health and environmental concern not only in highly urbanized areas, but also in rural areas that are used for intensive agricultural purposes, In this study, PM size- segregated samples were collected simultaneously for 12 months in a small town （Belle Glade, Florida）, which is the center of a vast sugarcane growing area and at Delray Beach, a coastal city in Palm Beach County, Florida. During the winter sampling period, when sugarcane foliage is burned just before harvest- ing to reduce the amount of plant matter to be handled, PM10 levels were 50% or higher than otherwise measured, indicating that sugarcane harvesting and processing is a major local source for PM10. For the rest of the year, PM10 levels at both sites are similar, suggesting that ambient PM levels at both sites are impacted by the major urban centers in Southern Florida. During late July and early August, the PM10 levels at both sites were substantially elevated and revealed the typical red-brownish color of Saharan dust. This has been reported to occur frequently with suitable meteorological conditions over the Atlantic Ocean coupled with a Sahara dust storm event. During the sugarcane harvesting season at Belle Glade, the concentrations of PAHs associated with PM10 were up to 15 times higher than those measured during the summer growing season, indicating a substantially higher exposure of the rural population to these often mutagenic and carcinogenic compounds.

关键词： Size segregated ambient particles PM10 PAHs Biomass burning Rural versus urban Saharan dust

New insights into the vitamin D requirements during pregnancy

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

Bone Research 2017年第3期5卷 161-176页

作者： Bruce W Hollis Carol L wagner Department of Pediatrics Darby Children's Research Institute Medical University of South Carolina

Pregnancy represents a dynamic period with physical and physiological changes in both the mother and her developing fetus. The dramatic 2-3 fold increase in the active hormone 1,25（OH）2D concentrations during the early weeks of pregnancy despite minimal increased calcium demands during that time of gestation and which are sustained throughout pregnancy in both the mother and fetus suggests an immunomodulatory role in preventing fetal rejection by the mother. While there have been numerous observational studies that support the premise of vitamin D＇s role in maintaining maternal and fetal well-being, until recently, there have been few randomized clinical trials with vitamin D supplementation. One has to exhibit caution, however, even with RCTs, whose results can be problematic when analyzed on an intent-to-treat basis and when there is high non-adherence to protocol （as if often the case）, thereby diluting the potential good or harm of a given treatment at higher doses. As such, a biomarker of a drug or in this case ＂vitamin＂ or pre-prohormone is better served. For these reasons, the effect of vitamin D therapies using the biomarker circulating 25（OH）D is a far better indicator of true ＂effect.＂ When pregnancy outcomes are analyzed using the biomarker 25（OH）D instead of treatment dose, there are notable differences in maternal and fetal outcomes across diverse racial/ethnic groups, with improved health in those women who attain a circulating 25（OH）D concentration of at least 100 nmol. L-1 （40 ng. mL-1）. Because ,an important issue is the timing or initiation of vitamin D treatment/supplementation, and given the potential effect of vitamin D on placental gene expression and its effects on inflammation within the placenta, it appears crucial to start vitamin D treatment before placentation （and trophoblast invasion）; however, this question remains unanswered. Additional work is needed to decipher the vitamin D requirements of pregnant women and the optimal timing of s

关键词： New insights into the vitamin D requirements during pregnancy

Control of Strain Hardening Behavior in High-Mn Austenitic Steels

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2014年第3期27卷 546-556页

作者： Wenwen Song Tobias Ingendahl wolfgang Bleck Steel Institute RWTH Aachen University Intzestr.1 52072 AachenGermany

Austenitic high-Mn steels with Mn contents between approximately 15 and 30 wt% gain much interest because of their excellent mechanical properties and the option for adjusting strain hardening behavior due to different deformation mechanisms. 2D and 3D composition-dependent stacking fault energy （SFE） maps indicate the effect of chemical composition and temperature on SFE and consequently on the deformation mechanisms. Three steels with different chemical compositions and the same or different SFE are characterized in quasi-static tensile tests. The control parameters of strain hardening behavior in the high-Mn austenitic steels are described, and consequences for future developments are discussed.

关键词： High-Mn austenitic steels Stacking fault energy Strain hardening