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Structural Changes ofαPhase in Furnace Cooled Eutectoid Zn-Al Based Alloy

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Journal of Materials Science & Technology 2007年第3期23卷 347-352页

作者： Y.h.Zhu K.C.Chan g.K.h.Pang T.M.Yue W.B.Lee Advanced Manufacturing Technology research Center Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong China department of Applied Physics The Hong Kong Polytechnic University Hong Kong China

Furnace cooling is a slow cooling process. It is of importance to study structural evolution and its effects on the properties of alloys during the furnace cooling. decomposition of aluminium rich α phase in a furnace cooled eutectoid Zn-Al based alloy was studied by transmission electron microscopy. Two kinds of precipitates in the α phase were detected in the FCZA22 alloy during ageing at 170℃. One was the hcp transitional α＂ m phase which aooears as directional rods and the round precipitates. The other was the fcc α＇m phase. 〈101〉. The orientation relationship between the a phase and transitional phase α＇m was determined as （022）α＇m （fcc）//（022^-）α（fcc）, [1^-11]α＇m, （fcc）//[2^-33]α（fcc）. The non-equilibrium phase decomposition of the α phase is discussed in correlation with the equilibrium phase relationships.

关键词： Phase decomposition Microstructural evolution Zn-Al alloys

A Service Oriented Analytics Framework for Multi-Level Marketing Business

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Journal of Software Engineering and Applications 2012年第8期5卷 527-535页

作者： rich C. Lee System Technology group IBM Taipei Chinese Taipei

Today’s enterprises have accumulated vast amount of data and keep exploding by business activities. These datasets may contain potential undiscovered business strategies as a key basis of competition;underpin new waves of productivity growth, innovation, and consumer surplus. data analysis is crucial in making managerial decisions. Although there are many Business Intelligence (BI) software of commercial and open source, but serving statistical purpose as exuberant as gNU-r (r) is rare. r is a highly extensible language and environment for providing a variety of statistical and graphical features. In enterprise environment, the source data are stored in various forms such as files, database, and streaming data. Currently analysts conduct data analysis in offline mode using statistical software. The offline mode means analysts 1) extract the desired data;2) store extracted data into files;3) manipulate software;4) draw analytical results;5) generate the inferences. Automating the statistical procedures by directly pulling source data will make critical decision sooner and less costly. It is a common practice that enterprise adopts Service-Oriented Architecture (SOA) to achieve its operation excellence. Since the business applications populate the source data during the operation processes, pulling the source data directly under SOA is the most effective way of data analysis. This paper demonstrates how service-oriented statistics engine was developed and how such a system benefits the business decision-making.

关键词： Software Engineering SOA Business Analytics Big data gNU-r

Effect of multi-pass multi-directional forging on tribological properties of Si-rich eutectoid ZA alloys

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Transactions of Nonferrous Metals Society of China 2021年第7期31卷 2024-2038页

作者： d.YOUSEFI r.TAghIABAdI M..hShAErI department of Materials Science and Metallurgy Imam Khomeini International UniversityQazvinIran

The effect of multi-pass multi-directional forge(MdF)on the tribological properties of ZA22−xSi alloy(x=0,4,8 wt.%)was *** results indicate that MdF breaks down the cast microstructure of alloys and produces a well-modified microstructure comprising finely distributed α- and η-phases and primary Si *** is also found that,despite the matrix work softening,MdFed ZA22−xSi alloys show high wear *** maximum wear resistance is observed in the five-pass MdFed ZA22−4Si sample,at the applied loads of 10 and 30 N,and its wear rates are lower than the wear rate of the as-cast ZA22 alloy by about 80% and 75%,*** also significantly decreases both average friction coefficient and friction coefficient fluctuation of the *** high resistance of the substrate to microcracking,formation of hard Si reinforcements,fine redistribution of α- and η-phases in the microstructure,and formation of tribolayers rich in Al and Zn oxides can be considered as the main factors improving the tribological properties.

关键词： multi directional forge(MdF) Zn−22Al alloy silicon tribology

Fabrication of ultrafine Nd-Fe-B powder by a modified reduction-diffusion process

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rare Metals 2006年第Z2期25卷 223-226页

作者： JANg T.S. LEE d.h. ChOI C.J. SEO W.S. LEE Y.h. department of Electronic Materials Engineering Sunmoon University Korea Powder Materials research Center Korea Institute of Machinery and Materials Korea Advanced Materials Analysis & Evaluation Center Korea Institute of Ceramic Engineering and Technology Korea

In order to obtain ultrafine Nd-Fe-B powder, a spray-dried precursor was treated by reduction-diffusion (r/d) process. And, unlike the conventional r/d process, calcium reduction that is a crucial step for the formation of Nd2Fe14B was performed without conglomerating the precursor with Ca powder. By adopting this modified process, it is possible to synthesize the hard magnetic Nd2Fe14B at the reaction temperature as low as 850 ℃. The average size of Nd2Fe14B particles that are uniformly distributed in the optimally treated powder was d2Fe14B particles were enclosed with thin layers of Nd-rich phase. Typical magnetic properties of such powder without eliminating impurity CaO were ihc=～5.9 kOe, Br=～5.5 kg, and (Bh)max=～6 MgOe.

关键词： NdFeB powder spray drying reduction-diffusion process Nd2Fe14B magnetic powder

geogenic Pollution of groundwater Quality in gampaha district, Sri Lanka: A Case Study of groundwater Acidification from rathupaswala

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International Journal of geosciences 2024年第8期15卷 590-604页

作者： Ishara Pathirage Anushka Upamali rajapaksha S. P. Sucharitha Bandara g. W. A. rohan Fernando Postgraduate Institute of Science University of Peradeniya Peradeniya Sri Lanka Instrument Centre Faculty of Applied Sciences University of Sri Jayewardenepura Colombo Sri Lanka Ecosphere resilience research Centre Faculty of Applied Sciences University of Sri Jayewardenepura Colombo Sri Lanka Central Environmental Authority Battaramulla Sri Lanka department of Physics The Open University of Sri Lanka Colombo Sri Lanka

Over recent decades, gampaha district, Sri Lanka, has experienced significant urbanisation and industrial growth, increasing groundwater demand due to limited and polluted surface water resources. In 2013, a community uprising in rathupaswala, a village in gampaha district, accused a latex glove manufacturing factory of causing groundwater acidity (ph his study evaluates the spatial and temporal changes in geochemical parameters across three transects in the southern part of gampaha district to 1) assess the impact of geological formations on groundwater;2) compare temporal variations in groundwater;and 3) explain acidification via a geochemical model. Seventy-two sample locations were tested for ph, electrical conductivity (EC), and anion concentrations (sulphate, nitrate, chloride and fluoride). depth to the water table and distance from the sea were measured to study variations across sandy, peaty, lateritic, and crystalline aquifers. results showed ph readings around 7 for sandy and crystalline aquifers, below 7 for peaty aquifers, and below 5 for lateritic aquifers, with significant water table fluctuations near rathupaswala area. Principal component analysis revealed three principal components (PCs) explaining 86.0% of the variance. PC1 (40.6%) correlated with ph, EC, and sulphate (saltwater intrusion), while PC2 (32.0%) correlated with nitrates and depth to the water table (anthropogenic nutrient pollution). A geochemical transport model indicated a cone of depression recharged by acidic groundwater from peat-soil aquifers, leading to acidic groundwater in rathupaswala area. Previous attributions of acidic ph to the over-exploitation of groundwater by the latex factory have been reevaluated;the results suggest natural acidification from prolonged water-rock interactions with iron-rich lateritic aquifers. groundwater ph is influenced by local climate, geology, topography, and drainage systems. It is recommended that similar water-rock interaction condit

关键词： groundwater Acidification Acid Sulphate Soils (AAS) Ion Chromatography groundwater Quality

Clinical immunology : 2nd ed.

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dIVErSITY OF EPhEMErOPTErA,PLECOPTErA ANd TrichOPTErA IN VArIOUS TrIBUTArIES OF TEMENggOr CATChMENT,PErAK,MALAYSIA

2001年

作者： edited by robert r. rich ... [et al.]

来源：畅想之星图书光盘版（南... 评论

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湿地科学 2007年第1期5卷 20-31页

作者： Che Salmah M r Abu hassan A Jongkar g School of Biological Sciences University Sains Malaysia11800 MindenPulau PinangMalaysia

A rich fauna of Ephemeroptera(mayfly),Plecoptera(stonefly) and Trichoptera(caddisfly)(EPT) were collected from 14 highland streams discharging into the Temenggor reservoir in Perak in the northern peninsular *** of the 3 orders,Ephemeroptera was the most diverse but Trichoptera was the most abundant.45 genera that belonged to 25 families of EPT were *** of EPT varied significantly between orders and types of streams they *** diversity and abundance were higher in the second and third order *** was no significant relationship between environmental parameters and diversity as well as abundance of EPT in these *** diversity indices together with EPT taxa richness scores referred to clean water environment,hence very suitable for these *** EPT taxa richness calculated for the 14 streams reflected that 13 out of 14 streams were undisturbed having good water quality(value of EPT taxa richness > 10).Previous logging and mining activities were suspected to be the main cause for tremendous disappearance of EPT genera in the Kelian *** no previous human activities were recorded around the Telang stream,natural phenomena possibly contributed to low abundance of these insects in the Telang stream.

关键词：襀翅目蜉蝣目毛翅目马来群岛丰度生物多样性湿地溪流昆虫

Foraging ecology and occurrence of 7 sympatric babbler species （Timaliidae） in the lowland rainforest of Borneo and peninsular Malaysia

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Current Zoology 2016年第4期62卷 345-355页

作者： Alison r. STYrINg roslina rAgAI Mohamed ZAKArIA Frederick h. ShELdON The Evergreen State College Olympia Washington 98505 USA grand Perfect Sdn. Bhd. ParkCity Commerce Square 97000 Bintulu Sarawak Malaysia department of Forest Management Faculty of Forestry Universiti Putra Malaysia Serdang Selangor Malaysia Museum of Natural Science and department of Biological Sciences Louisiana State University Baton Rouge Louisiana USA 70803

Understanding foraging strategies of birds is essential to understanding mechanisms of their community assembly. To provide such information on a key Southeast Asian rainforest family, the babblers （Timaliidae）, we evaluated foraging behavior and abundance in 7 morphologically and behaviorally similar sympatric species （Cyanoderma erythropterum, C. rufifrons, Stachyris maculata, S. nigricollis, S. poliocephala, Macronus ptilosus, and Mixornis gularis） in 5 habitats defined by structural complexity：（1） continuous native rainforest, （2） logged native rainforest fragments, （3） mature industrial tree plantation, （4） young industrial plantation, and （5） oil palm plantation. Enough data were obtained to compare abundance in all 7 species and foraging behavior in 5. All species were common in forest fragments and mature industrial tree plantations and less so in continuous rainforest and young industrial plantations; only M. gularis occurred in oil palm. In terms of foraging, M. gularis was the greatest generalist; C. rufifrons foraged mainly on live leaves in the forest midstory; and S. maculata, C. eryth- ropterum, and M. ptilosus foraged mainly on dead leaves suspended in understory vegetation at sig- nificantly different heights. The dead-leaf substrate depends on a rich supply of falling leaves and ex- tensive understory structure, conditions most common in native forest and old industrial plantations, and less so in mature forest, young plantations, and oil palm. Because of the importance of foraging data to understanding and managing biodiversity, we encourage the development of foraging fields in eBird （***）, so that birdwatchers may help collect these relatively rare data.

关键词： Brunei dead leaves logged forest plantation Sabah Sarawak.

The Chemical Industry: Shaping the 21st Century

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The Chemical Industry: Shaping the 21st Century