检索结果-南通市图书馆

Chinese Science Bulletin 2008年第5期53卷 759-767页

作者： zhang ShuWei j. Harald WALDERHAUG YANG Yuej.n College of Computer Engineering and Software Taiyuan University of Technology Taiyuan 030024 China Department of Earth Sciences University of Bergen AIl~gaten 415007 Bergen Norway State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Department of Applied Physics Taiyuan University of Technology Taiyuan 030024 China

Magnetic measurements were performed on apparently deformed igneous rocks of 23 sites from the southeastern part of the Taimyr Peninsula. Rock magnetism and reflected light microscopy analyses reveal that fine-grained titanomagnetites up to pure magnetites mainly carry the maj.rity of magnetic fabrics in the sills, and that the slightly coarser Ti-poor or -medium titanomagnetites carry most mag-netic fabrics in the basaltic flows. Magnetic anisotropies were determined by applying anisotropy of low-field magnetic susceptibility (AMS) on 180 unheated samples and 128 samples that had been pre-viously heated to 600°C during a paleomagnetic study to detect heating effects on the anisotropy of magnetic susceptibility (AMS) properties of volcanic rocks. Laboratory heating significantly affects anisotropy variations of these igneous rocks corresponding to the mineralogical changes during the heat treatment.

关键词：岩石磁学磁各向异性玄武岩折叠式岩床俄罗斯

Systematic position of Myrtama Ovcz. & Kinz. based on morphological and nrDNA ITS sequence evidence

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2006年第A1期51卷 117-123页

作者： zhang Daoyuan zhang Yuan GASKIN j. F. CHEN Zhiduan Turpan Eremophytes Botanical Garden Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Ururaqi 830011 China Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China USDA-ARS-NPARL PO Box 463 Sidney MT 59270 USA

Myrtama 是以它的词法怪癖在 1970 年代从 Myricaria elegans Royle 说出的一个类。自从它的开始，这个类和它的系统的位置的建立被争论了。它从 Tamaricaceae 的 10 种类的序列被报导，并且由 PAUP 4.0b8 和贝叶斯的推理分析了重建发... 详细信息

Myrtama 是以它的词法怪癖在 1970 年代从 Myricaria elegans Royle 说出的一个类。自从它的开始，这个类和它的系统的位置的建立被争论了。它从 Tamaricaceae 的 10 种类的序列被报导，并且由 PAUP 4.0b8 和贝叶斯的推理分析了重建发展史。一个单身者它的树分别地从最大的吝啬和 MrBayes 分析被产生。分子的数据集合作为一个姐妹组作为 monophyletic 类，和 Myrtama 为 Tamarix 和 Myricaria 显示出强壮的支持到类 Myricaria。基于词法差别，一棵单个词法树也被产生，在哪个二个主要的系存在但是 Myrtama 是到 Tamarix，而非 Myricaria 的一个姐妹组。从 DNA 序列和 Myicaria elegans 应该被放进既不 Myricaria 也不 Tamarix，但是放在它的自己的 monotypic 类的词法人物支持的证据。

关键词： ITS序列形态特征系统位置 DNA测序

Particle shape characterisation and classification using automated microscopy and shape descriptors in batch manufacture of particulate solids

在线全文

学校读者我要写书评

暂无评论

Particuology 2016年第1期14卷 61-68页

作者： Yang zhang j.ng j. Liu Lei zhang j.rge Calderon De Anda Xue Z. Wang School of Chemistry and Chemical Engineering South China University of Technology 381 Wushan Road Guangzhou 510641 China School of Bioscience and Bioengineering South China University of Technology Guangzhou Higher Education Mega Centre Panyu District Guangzhou510006 China Institute of Particle Science and Engineering School of Chemical and Process Engineering University of Leeds Leeds I52 9JT UK

It is known that size alone, which is often defined as the volume-equivalent diameter, is not sufficient to characterize many particulate products. The shape of crystalline products can be as important as size in many applications, Traditionally, particulate shape is often defined by several simple descriptors such as the maximum length and the aspect ratio. Although these descriptors are intuitive, they result in a loss of information about the original shape. This paper presents a method to use principal component analysis to derive simple latent shape descriptors from microscope images of particulate products made in batch processes, and the use of these descriptors to identify batch-to-batch variations. Data from batch runs of both a laboratory crystalliser and an industrial crystallisation reactor are analysed using the described approach. Qualitative and quantitative comparisons with the use of traditional shape descriptors that have nhwical meanings and Fourier shape descriptors are also made.

关键词： Batch-to-batch variation Classification Principal components analysis Shape descriptors

Multiplexed cytokine detection on plasmonic gold substrates with enhanced near-infrared fluorescence

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2013年第2期6卷 113-120页

作者： Bo zhang j.rdan Price Guosong Hong Scott M. Tabakman Hailiang Wang j.stin A. j.rrell j. Feng paul j. Utz Hongj.e Dai Department of Chemistry Stanford University Stanford California USA Department of Medicine Division of Immunology and Rheumatology Stanford University School of Medicine Stanford California USA Institute for Immunity Transplantation and Infection Stanford University School of Medicine Stanford California USA

Protein microarrays based on fluorescence detection have been widely utilized for high-throughput functional proteomic analysis. However, a drawback of such assays has been low sensitivity and narrow dynamic range, limiting their capabilities, especially for detecting low abundance biological molecules such as cytokines in human samples. Here, we present fluorescence-enhancing microarrays on plasmonic gold films for multiplexed cytokine detection with up to three orders of magnitude higher sensitivity than on conventional nitrocellulose and glass substrates. Cytokine detection on the gold plasmonic substrate is about one to two orders of magnitude more sensitive than enzyme-linked immunosorbent assay （ELISA） and can be multiplexed. A panel of six cytokines （Vascular endothelial growth factor （VEGF）, Interleukin 1β （IL-1β）, Interleukin 4 （IL-4）, Interleukin 6 （IL-6）, Interferon γ （IFN-γ）, and Tumor necrosis factor （TNF）） were detected in the culture media of cancer cells. This work establishes a new method of high throughput multiplexed cytokine detection with higher sensitivity and dynamic range than ELISA.

关键词： microarray cytokine plasmonic multiplex near infrared fluorescence

Global mitigation efforts cannot neglect emerging emitters

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2022年第12期9卷 82-89页

作者： Can Cui Dabo Guan Daoping Wang j.ng Meng Vicky Chemutai paul Brenton Shaohui zhang Yuli Shan Qiang zhang Steven j.Davis Department of Earth System Science Tsinghua University The Bartlett School of Sustainable Construction University College London Department of Computer Science and Technology University of Cambridge Centre for Nature and Climate World Economic Forum School of Urban and Regional Science Shanghai University of Finance and Economics The World Bank School of Economics and Management Beihang University International Institute for Applied Systems Analysis School of Geography Earth and Environmental Sciences University of Birmingham Department of Earth System Science University of California Irvine Department of Civil and Environmental Engineering University of California Irvine

International efforts to avoid dangerous climate change have historically focused on reducing energy-related CO2emissions from countries with either the largest economies(*** EU and the USA)and/or the largest populations(*** and India).However,in recent years,emissions have surged among a different and much less-examined group of countries,raising concerns that a next generation of high-emitting economies will obviate current mitigation ***,we analyse the trends and drivers of emissions in each of the 59 countries where emissions in 2010-2018 grew faster than the global average(excluding China and India),proj.ct their emissions under a range of longer-term energy scenarios and estimate the costs of decarbonization *** emissions from these ’emerging emitters’ reach as much as 7.5 GtCO2/year in the baseline 2.5° scenari—substantially greater than the emissions from these regions in previously published scenarios that would limit warming to 1.5℃ or even 2℃.Such unanticipated emissions would in turn require non-emitting energy deployment from all sectors within these emerging emitters,and faster and deeper reductions in emissions from other countries to meet international climate ***,the annual costs of keeping emissions at the low level are in many cases 0.2%-4.1% of countries’ gross domestic production,pointing to potential trade-offs with poverty-reduction goals and/or the need for economic support and low-carbon technology transfer from historically high-emitting *** results thus highlight the critical importance of ramping up mitigation efforts in countries that to this point have been largely ignored.

关键词： emerging emiters developing countries climate change mitigation CO_2 emissions net zero

Robust Needle Localization and Enhancement Algorithm for Ultrasound by Deep Learning and Beam Steering Methods

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

j.urnal of Computer Science & Technology 2021年第2期36卷 334-346页

作者： j.n Gao paul Liu Guang-Di Liu Le zhang College of Computer Science Sichuan UniversityChengdu 610065China Stork Healthcare Chengdu 610000China College of Computer and Information Science Southwest UniversityChongqing 400715China West China Biomedical Big Data Center West China HospitalSichuan UniversityChengdu 610065China Pera Corporation Ltd. Beijing 100025China

Ultrasound(US)imaging is clinically used to guide needle insertions because it is safe,real-time,and low *** localization of the needle in the ultrasound image,however,remains a challenging problem due to specular reflection off the smooth surface of the needle,speckle noise,and similar line-like anatomical *** study presents a novel robust needle localization and enhancement algorithm based on deep learning and beam steering methods with three key ***,we employ beam steering to maximize the reflection intensity of the needle,which can help us to detect and locate the needle ***,we modify the U-Net which is an end-to-end network commonly used in biomedical segmentation by using two branches instead of one in the last up-sampling layer and adding three layers after the last down-sample ***,the modified U-Net can real-time segment the needle shaft region,detect the needle tip landmark location and determine whether an image frame contains the needle by one ***,we develop a needle fusion framework that employs the outputs of the multi-task deep learning(MTL)framework to precisely locate the needle tip and enhance needle shaft ***,the proposed algorithm can not only greatly reduce the processing time,but also significantly increase the needle localization accuracy and enhance the needle visualization for real-time clinical intervention applications.

关键词： ultrasound deep learning segmentation classification optimization

An improved culturing method for opiine fruit fly parasitoids and its application to parasitoid monitoring in the field

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2018年第1期25卷 99-108页

作者： Ayad Masry Michael j. Furlong Anthony R. Clarke j.hn paul Cunningham School of Earth Environmental and Biological Sciences School Queensland University of Technology (QUT) Brisbane Queensland Australia School of Biological Sciences the University of Queensland St Lucia Queensland Australia plant Biosecurity Cooperative Research Centre Bruce ACT Australia Department of Economic Development Jobs Transport and Resources AgriBio Centre La Trobe University Bundoora Victoria Australia

Good culturing methods play an important role in the study of insect behavior and its application to pest management. Here, we describe and validate a new method for rearing the parasitoid wasp, Diachasmirnorpha kraussii, which attacks some of the world＇s worst fruit fly pests and is an internationally used biological control agent. Our method differs from standard culturing approaches by presenting adult wasps with host- infested artificial media within a ＂culturing bag,＂ which mimics a natural （fruit） oviposition substrate. In laboratory trials using wild collected D. kraussii, the culturing bag method was compared to the use of host-infested nectarines, and a commonly used laboratory method of presenting host-infested artificial media within Petri dishes. The culturing bag method proved to be a significant improvement on both methods, combining the advantages of high host survival in artificial media with parasitism levels that were the equivalent to those recorded using host-infested fruits. In our field study, culturing bags infested with the Queensland fruit fly, Bactrocera tryoni, and hung in a mixed peach and nectarine orchard proved to be effective ＂artificial fruits＂ attracting wild D. kraussii for oviposition. Significantly more adult wasps were reared from the culturing bags compared to field collected fruits. This was shown to be due to higher fruit fly larval density in the bags, as similar percentage parasitism rates were found between the culturing bags and ripe fruits. We discuss how this cheap, time-efficient method could be applied to collecting and monitoring wild D. kraussii populations in orchards, and assist in maintaining genetic variability in parasitoid laboratory cultures.

关键词： Bactrocera biological control fruit fly mass rearing natural enemies Tephritidae wasp

Arthropod prey of imported fire ants （Hymenoptera： Formicidae） in Mississippi sweetpotato fields

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2013年第4期20卷 467-471页

作者： Tahir Rashid j.an Chen j.mes T. Vogt paul j. McLeod Aicorn State University Extension~Research Demonstration Farm & Tech Transfer Center Mound Bayou Mississippi USDA ARS Bio- logical Control of Pests Research Unit Stoneville Mississippi USDA FS Inventory & Analysis Knoxville Tennessee Department of Entomology University of Arkansas Fayetteville Arkansas United States

The red imported fire ants, Solenopsis invicta （Buren）, are generally considered pests. They have also been viewed as beneficial predators feeding on other insect pests of various agroecosystems. This study documents the foraging habits of fire ants in a sweetpotato field in Mississippi. Fire ant foraging trails connecting outside colonies to a sweetpotato field were exposed and foraging ants moving out of the field toward the direction of the colony were collected along with the solid food particles they were carrying. The food material was classified as arthropod or plant in origin. The arthropod particles were identified to orders. Fire ant foragers carried more arthropods than plant material. Coleoptera and Homoptera were the most abundant groups preyed upon. These insect orders contain various economically important pests of sweetpotato. Other maj.r hexapod groups included the orders Hemiptera, Diptera and Collembola. The quantity of foraged material varied over the season. No damage to sweetpotato roots could be attributed to fire ant feeding. Imported fire ant foraging may reduce the number of insect pests in sweetpotato fields.

关键词： foraging imported fire ant predation Solenops& invicta sweetpotato

Flow of Steel in Mold Region During Continuous Casting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

j.urnal of Iron and Steel Research International 2007年第2期14卷 30-35,41页

作者： zhang Xing-guo zhang Wen-xiao j.N j.n-ze j. W. Evans Research Center of Foundry Engineering Dalian University of Technology Dalian 116023 Liaoning China Department of Material Science and Engineering University of California at Berkeley Berkeley CA94720 USA

The particle image velocimetry （PIV） technique was used to study the fluid flow phenomena that occurred during continuous casting, using a water model with dimensions of 1 840mm× 280 mm. Two types of solidified shells, i. e. , the smooth type and the coarse type, were used to characterize the dendrite in order to simulate different liquid-solid interfacial conditions. The influence of the nozzle angle and the immersion depth of nozzle, as well as the casting speed on the flow behavior was investigated quantitatively. The results were as follows：（1） There are two large recirculations above and below the fluid j.t in the mold, respectively, under the smooth interface condition. However, in the case of the dendrite solidified shell, it was found that the flow velocity of the fluid decreased and more smaller vortices appeared in the upper region of the mold. （2） The angle and the immersion depth of nozzle are two important factors affecting the flow pattern, and they are also capable of bringing about the change in the flow direction. （3） The higher the casting speed, the higher are the j.t stream and the impacting point on the narrow face. However, the high casting speed causes serious fluctuation of the meniscus, and correspondingly leads to various defects.

关键词： particle image velocimetry continuous casting steel fluid flow

Three-dimensional electric field calculations for wire chamber using element refinement method in ANSYS

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2018年第12期29卷 96-101页

作者： Yao-Feng zhang j. Barney M. B. Tsang Chun-Lei zhang The Key Laboratory of Beam Technology and Material Modification of Ministry of Education College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875 China Beij.ng Radiation Center Beijing 100875 China National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy Michigan State University East Lansing MI 48824 USA

Finite element analysis(FEA) method was employed to perform three-dimensional(3D) electric field simulations for gas detectors with multiple wire electrodes.A new element refinement method developed for use in conj.nction with the FEA program ANSYS allows successful meshing of the wires without physically inputting the wires in the chamber geometry. First, we demonstrate a model with only one wire, for which we calculate the potential distributions on the central plane and the end-cap region. The results are compared to the calculations obtained using GARFIELD, a two-dimensional program that uses the nearly exact boundary element method. Then we extend the method to same model, but with seven *** results suggest that the new method can be applied easily to the 3D electric field calculations for complicated gas detectors with many wires and complicated geometry such as multiwire proportional chambers and time proj.ction chambers.

关键词：有限元素分析 ANSYS 电场计算精炼方法电线房间三维电场模拟