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2004

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Articles 211 - 240 of 3873

Full-Text Articles in Physical Sciences and Mathematics

Automatic Model Structuring From Text Using Biomedical Ontology, Joshi R., Li X., Ramachandaran S., Tze-Yun Leong Dec 2004

Automatic Model Structuring From Text Using Biomedical Ontology, Joshi R., Li X., Ramachandaran S., Tze-Yun Leong

Research Collection School Of Computing and Information Systems

Bayesian Networks and Influence Diagrams are effective methods for structuring clinical problems. Constructing a relevant structure without the numerical probabilities in itself is a challenging task. In addition, due to the rapid rate of innovations and new findings in the biomedical domain, constructing a relevant graphical model becomes even more challenging. Building a model structure from text with minimum intervention from domain experts and minimum training examples has always been a challenge for the researchers. In the biomedical domain, numerous advances have been made which may make this dream a possibility now. We are currently trying to build a general …

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Diel Foraging Behavior Of American White Pelicans ()Pelecanus Erythrorhynchos) On Experimental Aquaculture Ponds , Scott J. Werner Dec 2004

Diel Foraging Behavior Of American White Pelicans ()Pelecanus Erythrorhynchos) On Experimental Aquaculture Ponds , Scott J. Werner

United States Department of Agriculture Wildlife Services: Staff Publications

Videography and night vision equipment were used to observe the diurnal and nocturnal activities of American white pelicans (Pe1ecanus erythrorhynchos) (N= 6) foraging on three experimental (0.04 ha) channel catfish (Ictalurus punctatus) aquaculture ponds in March 2001. Captive pelicans spent most time foraging per hour from 1700 through 2300 h (CST). No foraging was observed from 0700 through 0800 h. Fish captures per hour were greatest from 1700 through 1900 h. On average, captive pelicans (N = 5) consumed 1.0 ± 0.2 kg of catfish per bird per day during the 10-d foraging …

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Genetic Methods Improve Accuracy Of Gender Determination In Beavers, Christen Lenney Williams, Stewart W. Breck, Bruce W. Baker Dec 2004

Genetic Methods Improve Accuracy Of Gender Determination In Beavers, Christen Lenney Williams, Stewart W. Breck, Bruce W. Baker

United States Department of Agriculture Wildlife Services: Staff Publications

Gender identification of sexually monomorphic mammals can be difficult. We used analysis of zinc-finger protein (Zfx and Zfy) DNA regions to determine gender of 96 beavers (Castor canadensis) from 3 areas and used these results to verify gender determined in the field. Gender was correctly determined for 86 (89.6%) beavers. Incorrect assignments were not attributed to errors in any one age or sex class. Although methods that can be used in the field (such as morphological methods) can provide reasonably accurate gender assignments in beavers, the genetic method might be preferred in certain situations.

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Education In The Environment: A Hands-On Student Research And Outdoor Learning Experience: Quarterly Progress Report, Period Ending November 30, 2004, Margaret N. Rees Nov 2004

Education In The Environment: A Hands-On Student Research And Outdoor Learning Experience: Quarterly Progress Report, Period Ending November 30, 2004, Margaret N. Rees

Reports (PLI Education)

During the past three-months, the focus of the university’s efforts has been 1) making progress on the hiring of permanent project managers for the Education in the Environment Strategy and the Forever Earth / Wonderful Outdoor World on the Water (WOW) projects; 2) completing legal review of the cooperative agreement and standard operating procedures required for the university to assume operations of the Forever Earth vessel; and 3) writing curriculum for the WOW and Forever Earth projects.

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Population Recovery And Differential Heat Shock Protein Expression For The Corals Agaricia Agaricites And A. Tenuifolia In Belize, Martha L. Robbart, Paulette M. Peckol, Stylianos P. Scordilis, H. Allen Curran, Jocelyn Brown-Saracino Nov 2004

Population Recovery And Differential Heat Shock Protein Expression For The Corals Agaricia Agaricites And A. Tenuifolia In Belize, Martha L. Robbart, Paulette M. Peckol, Stylianos P. Scordilis, H. Allen Curran, Jocelyn Brown-Saracino

Geosciences: Faculty Publications

Over recent decades, coral reefs worldwide have experienced severe sea-surface temperature (SST) anomalies. Associated with an El Niño-Southern Oscillation (ENSO) event of 1997-1998, nearly 100% mortality of the space-dominated coral Agaricia tenuifolia was reported at several shelf lagoonal sites of the Belize barrier reef system; a less abundant congener, A. agaricites, had lower mortality rates. We assessed A. agaricites and A. tenuifolia populations at coral reef ridges in the south-central sector of the Belize shelf lagoon and forereef sites to document recovery following the 1998 ENSO event and subsequent passage of Hurricane Mitch. To investigate the difference in heat …

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Ip Algorithm Applied To Proteomics Data, Christopher Lee Green Nov 2004

Ip Algorithm Applied To Proteomics Data, Christopher Lee Green

Theses and Dissertations

Mass spectrometry has been used extensively in recent years as a valuable tool in the study of proteomics. However, the data thus produced exhibits hyper-dimensionality. Reducing the dimensionality of the data often requires the imposition of many assumptions which can be harmful to subsequent analysis. The IP algorithm is a dimension reduction algorithm, similar in purpose to latent variable analysis. It is based on the principle of maximum entropy and therefore imposes a minimum number of assumptions on the data. Partial Least Squares (PLS) is an algorithm commonly used with proteomics data from mass spectrometry in order to reduce the …

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Secure Hardware Enhanced Myproxy: A Ph.D. Thesis Proposal, John Marchesini, Sean Smith Nov 2004

Secure Hardware Enhanced Myproxy: A Ph.D. Thesis Proposal, John Marchesini, Sean Smith

Computer Science Technical Reports

In 1976, Whitfield Diffie and Martin Hellman demonstrated how "New Directions In Cryptography" could enable secure information exchange between parties that do not share secrets. In order for public key cryptography to work in modern distributed environments, we need an infrastructure for finding and trusting other parties' public keys (i.e., a PKI). A number of useful applications become possible with PKI. While the applications differ in how they use keys (e.g., S/MIME uses the key for message encryption and signing, while client-side SSL uses the key for authentication), all applications share one assumption: users have keypairs. In previous work, we …

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Pluton Zonation Unveiled By Gamma-Ray Spectrometry And Magnetic Susceptibility; A Case Study Of The Sheeprock Granite, Western, Utah, Paul D. Richardson Nov 2004

Pluton Zonation Unveiled By Gamma-Ray Spectrometry And Magnetic Susceptibility; A Case Study Of The Sheeprock Granite, Western, Utah, Paul D. Richardson

Theses and Dissertations

A radiometric survey of the zoned 21 Ma, A-type Sheeprock granite, western Utah, combined with measurements of magnetic susceptibility and field observations were analyzed using a geographic information system. The intrusion spans 25 square km and is roughly eliptical in shape with its long axis trending northwest. Concentration maps (composed of more than 500 survey stations) of eU, eTh, texture, magnetic susceptibility, color, and joint density help to constrain magmatic and post-magmatic processes related to its chemical and physical zonation. Uranium ranges from 3.9 to 26.9 ppm (mean 12.7) and thorium from 1.7 to 125.7 ppm (mean 45.5). Similarities in …

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Attractiveness Of Brown Rice Baits To Non-Target Birds In Harvested Corn And Soybean Fields, George M. Linz, Gregory A. Knutsen, H. Jeffrey Homan, William J. Bleier Nov 2004

Attractiveness Of Brown Rice Baits To Non-Target Birds In Harvested Corn And Soybean Fields, George M. Linz, Gregory A. Knutsen, H. Jeffrey Homan, William J. Bleier

United States Department of Agriculture Wildlife Services: Staff Publications

Brown rice is used as a bait-carrier for the avicide DRC-1339 (3-chloro-4-methyladhe) when baiting blackbirds (Icteridae). In March and April 1996 and 1997, we assessed non-target granivorous bird use of rice-baited plots placed in harvested corn and soybean fields in eastern South Dakota for 168 observation hours. In both years combined, we identified 10 and 14 granivorous species in corn and soybean fields, respectively. In 1996 (X = 0.2, SE = 0.04) and 1997 (X = 1.2, SE = 0.38), total numbers of granivores min-1 were similar between crops (P ≥ 0.322). In 1996, bird numbers …

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The Electrochemical Performance Of Modified Spinel At Elevated Temperature, Zhen-Ping Cai, Xiao-Hong Chen, Shi-Gang Lu, Ming-Xun Li, Wei-Hua Jin Nov 2004

The Electrochemical Performance Of Modified Spinel At Elevated Temperature, Zhen-Ping Cai, Xiao-Hong Chen, Shi-Gang Lu, Ming-Xun Li, Wei-Hua Jin

Journal of Electrochemistry

The modified LiMn2O4 cathode materials for lithium ion batteries have been synthesized by solid-state reaction. The crystal structure and electrochemical performance of products have been investigated by SEM, XRD and electrochemical measurements. The XRD analysis indicated that all the synthesized products possess Fd3m spinel LiMn2O4 structure. Those modified LiMn2O4 materials showed improved cycling capacity over pure spinels at high temperature and room temperature.

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Electrochemical Behaviours Of Hemoglobin-Ddab-Modified Powder Microelectrode And The Application Of The Powder Microelectrode In Determination Of Nitric Oxide, Zhi-Mou Guo, Huan Liu, Jian Chen, Wen-Ting Zhang Nov 2004

Electrochemical Behaviours Of Hemoglobin-Ddab-Modified Powder Microelectrode And The Application Of The Powder Microelectrode In Determination Of Nitric Oxide, Zhi-Mou Guo, Huan Liu, Jian Chen, Wen-Ting Zhang

Journal of Electrochemistry

The electrochemical behaviours of DDAB-Hb-PME were studied in this paper. The (apparent) surface concentration of Hb was enhanced greatly by using the powder microelectrode (technique). NO reacts with Hb and absorbs on the surface of the modified carbon powder. Therefore, the output of the electrode was enhanced greatly by employing PME with higher reaction surface (area). The sensitivity of DDAB-Hb-PME is 3.1 mA/μmol·L-1·cm2, which is much larger than the values obtained with the traditional electrodes. The detection limit is 9 nmol·L-1 and the linear response range is 9～100 nmol·L-1.

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Improvement And Its Mechanism Of Storage Performance Of Ni-Mh Battery, Xiao-Feng Li, Li-Ping Ma, Yu-Wan Lou, Feng Li, Bao-Jia Xia Nov 2004

Improvement And Its Mechanism Of Storage Performance Of Ni-Mh Battery, Xiao-Feng Li, Li-Ping Ma, Yu-Wan Lou, Feng Li, Bao-Jia Xia

Journal of Electrochemistry

The storage performance of nickel-metal-hydride (Ni-MH) battery was studied by using galvanostatic charge-discharge and cyclic voltammetry. The experimental results indicated that CoOOH could not be completely restored after its being thoroughly reduced at lower potential, which might weaken electric conduction network in the positive electrode and result in fading of electrochemical properties of Ni-MH battery. Addition of nickel powder as a conductive agent into the positive electrode was beneficial to the capacity recovery after storage.

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Preparation And Electrochemical Magnesium Insertion Behaviors Of Mgv2O6, Hua-Tang Yuan, Li-Fang Jiao, Jian-Sheng Cao, Xiu-Sheng Liu, Ming Zhao, Yong-Mei Wang Nov 2004

Preparation And Electrochemical Magnesium Insertion Behaviors Of Mgv2O6, Hua-Tang Yuan, Li-Fang Jiao, Jian-Sheng Cao, Xiu-Sheng Liu, Ming Zhao, Yong-Mei Wang

Journal of Electrochemistry

MgV2O6 was synthesized by conventional solid-state reaction from MgO and V2O5 as starting materials. X-Ray diffraction analysis showed that the prepared sample belongs to the monoclinic structure. Electrochemical magnesium insertion from aprotic electrolytes such as organomagnesium halides into this host was found possible and exhibited charge/discharge circulation.

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Electrocatalytic Performances Of Carbon Nanotube Air Electrode For Oxygen Reduction, Feng-Ming Zhao, Chun-An Ma Nov 2004

Electrocatalytic Performances Of Carbon Nanotube Air Electrode For Oxygen Reduction, Feng-Ming Zhao, Chun-An Ma

Journal of Electrochemistry

The air electrodes with different mass ratio of Pt/active carbon or carbon nanotube as catalyst layer material have been prepared. The electrocatalytic performances for oxygen reduction were evaluated by means of polarization curve and electrochemical impedance spectroscopy (EIS). The results disclosed that carbon nanotubes dealt with nitric acid in the catalyst layer had been improved obviously on the electrocatalytic activity. After the surface of carbon nanotube was oxygenated and aggraded with platinum, the catalyst had obviously effects on the electrocatalytic activity. The air electrode with the mass ratio of active carbon to Pt/carbon nanotube in 4∶1 showed better electrocatalytic activity, …

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Electrochemical Investigations On Pitting Susceptibility Of Iron-Based Alloy, Wei-Shan Li, Hong-Yu Chen, Zhong-Zhi Yuan, Hong Li, Qi-Ming Huang, Dong-Sheng Lv Nov 2004

Electrochemical Investigations On Pitting Susceptibility Of Iron-Based Alloy, Wei-Shan Li, Hong-Yu Chen, Zhong-Zhi Yuan, Hong Li, Qi-Ming Huang, Dong-Sheng Lv

Journal of Electrochemistry

The formation process of passive film on iron and electronic properties and pitting susceptibility of an iron-based alloy are investigated by using linear potential sweep, alternative current impedance and electrochemical nose technologies. The relationship between reciprocal square capacitance and potential following the Mott-Schottky behavior is limited at a narrow rang of low potentials. At higher potentials, linear relationship between reciprocal capacitance and potential is obtained, which is ascribed to the increasing thickness of the passive film with potential. The donor density of the passive film is influenced by the formation potential of the film, passivator and microstructure. The decrease in …

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LicoXNi1-XO2 Cathode Materials Prepared By Electrolysis Of Co And Ni, Jin-Ping Wei, Xin Sun, Xiao-Yu Wang, Xi-Kui Bian, Jin-Ling Zhai, Yan-Jie Yan-Jie Nov 2004

LicoXNi1-XO2 Cathode Materials Prepared By Electrolysis Of Co And Ni, Jin-Ping Wei, Xin Sun, Xiao-Yu Wang, Xi-Kui Bian, Jin-Ling Zhai, Yan-Jie Yan-Jie

Journal of Electrochemistry

A new electrolytic method was developed to prepare LiCoxNi1-xO2 as a cathode material of lithium-ion battery. Contrary to the traditional method, electrolytic method is a potential method with simple process to industrialization and no pollution. Metal cobalt and nickel were electrolysed in parallel to prepare the precursor of CoxNi1- x(OH)2.Different compositional precursors could be conveniently prepared by changing electrolytic current. The LiCo0.3Ni0.7O2 cathode prepared by this method was found favorable charge-discharge and cycle properties. For the LiCo0.3Ni0.7O2 cathode material, …

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Applications Of New Activated Carbon Meterials In The Electric Double-Layer Capacitor, Jian-Jun Zhang, Hua Jiang, Jian-Hui Fang, Li-Yi Shi, Ren-He Yin, Yi Wen, Ji-Quan Liu Nov 2004

Applications Of New Activated Carbon Meterials In The Electric Double-Layer Capacitor, Jian-Jun Zhang, Hua Jiang, Jian-Hui Fang, Li-Yi Shi, Ren-He Yin, Yi Wen, Ji-Quan Liu

Journal of Electrochemistry

A new type activated carbon whose precursor was coconut shell could be obtained using specific physics-chemistry activation, and the activated carbon was applied as the material of electrode in EDLC (electrical double-layer capacitor),which had a large specific capacitance, and could charge and discharged in some large currents. Carbon dioxide and acid were used to modify carbon,and the effects of post-treatment on surface area and pore volume were investigated. A moulding method which has influence on some properties of carbon electrode with PTFE additive was researched in the paper.

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Effect Of Fe3+ Dopen Of Titanium Dioxide Film On Absorption Spectra And Photo Catalysis, Mei-Qun Xiao, Jia-Nian Shen, Moucheng Li, Peng-Fei Wu, Dong Liu, Yu-Juan Zhang Nov 2004

Effect Of Fe3+ Dopen Of Titanium Dioxide Film On Absorption Spectra And Photo Catalysis, Mei-Qun Xiao, Jia-Nian Shen, Moucheng Li, Peng-Fei Wu, Dong Liu, Yu-Juan Zhang

Journal of Electrochemistry

Photo-catalytic titanium dioxide film in nano crystalline has been prepared by electrochemical oxidation process and adding different amount of ferric ion into the electrolyte during the anodic oxidation.The effects of Fe3+ dopen on absorption spectra and photo-catalytic of the titanium dioxide films have been studied. It shows that the Fe3+ dopen caused the red shife of the absorption edge for the incoming light and exhibited the improved photocatalytic reactivity.

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Anodic Dissolution Of Aluminum In Koh-Ethanol Solutions, Hai-Bo Shao, Jian-Ming Wang, Xiao-Yan Wang, Yi Zheng, Jian-Qing Zhang Nov 2004

Anodic Dissolution Of Aluminum In Koh-Ethanol Solutions, Hai-Bo Shao, Jian-Ming Wang, Xiao-Yan Wang, Yi Zheng, Jian-Qing Zhang

Journal of Electrochemistry

The feasibility of employing aluminum in KOH ethanol solution as a battery anode system was discussed. Weight loss measurement showed that the corrosion rate of Al is low enough to be used in sealed batteries. Through the measurements done by anodic polarization, EIS and galvanostatic discharge, it was found that Al is electrochemical active in a wide potential range in this system, and its discharge mechanism is similar to that of Al in aqueous solution. The discharge potential increased rapidly after a period of time, which might be caused by the discharge products depositing on the electrode surface.

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Study On Mass Transport In Liquid Layer Adjacent To The Electrode Through Transmission Vop-Spectroellipsometry, Wei Zhu, Yu-Ru Yang, Zong-Qing Huang Nov 2004

Study On Mass Transport In Liquid Layer Adjacent To The Electrode Through Transmission Vop-Spectroellipsometry, Wei Zhu, Yu-Ru Yang, Zong-Qing Huang

Journal of Electrochemistry

In electrochemical system, the mass transport process in liquid layer adjacent to electrode is studied through theoretical analysis only.The diffusion process can be analyzed theoretically by Fick's law for homogeneous media. Up to now, none of satisfied experimental method has been reported for studying mass transport of a whole process in liquid media yet. This paper described the experimental approach to explore mass transport in electrochemical system by transmission Vop-spectroellipsometry briefly.

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Studies On The Electrochemical Preparation And Electrochemical Properties Of Conducting Polymers——Brief Introduction To The Research Work Of Electrochemistry Of Conducting Polymers In Cas Key Laboratory Of Organic Solids(I), Yong-Fang Li Nov 2004

Studies On The Electrochemical Preparation And Electrochemical Properties Of Conducting Polymers——Brief Introduction To The Research Work Of Electrochemistry Of Conducting Polymers In Cas Key Laboratory Of Organic Solids(I), Yong-Fang Li

Journal of Electrochemistry

Conducting polymers have drawn much attention since the discovery of conducting polyacetylene in 1977, due to the novelty and curiosity of their structure and properties as well as their promising applications in many aspects. Among the studies of conducting polymers, the electrochemical preparation and electrochemical properties of conducting polymers are of special importance, because the electropolymerization is a main method for preparing conducting polymer films and the electrochemical properties are the basis for their applications in the fields of electrode materials for batteries, electrocatalysis, electrochromic display, etc. We are one of the earliest research groups in the world to perform …

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Preparation And Photo-Catalyst Properties Of The α-Fe2O3-Tio2 Films On Sodium Alginate Polymer, Li-Qin Chen, Huai-Zhen Zhong, Ri-Yao Chen, Xi Zheng, Zhen Chen Nov 2004

Preparation And Photo-Catalyst Properties Of The α-Fe2O3-Tio2 Films On Sodium Alginate Polymer, Li-Qin Chen, Huai-Zhen Zhong, Ri-Yao Chen, Xi Zheng, Zhen Chen

Journal of Electrochemistry

Three new nano thin films of α-Fe2O3, TiO2 and α-Fe2O3-TiO2 by doping their powder with sodium alginate polymer were prepared. Surface structure and catalytic activities of the films were characterized by FTIR, XRD, PL, TEM and I-V techniques. The results of UV-visible absorption showed that the methylene blue was mineralized in aqueous of α-Fe2O3/SA, TiO2/SA and (α-(Fe2O3))-TiO2 /SA upon radiation with ultra violet light. α-Fe2O3 enhanced their photo-decolorized-activities by doping 15% TiO2.

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Investigation Of Pulse Potential-Modulated Coulometry For Co2 Detection, Hai-Chuan Wang, Bing-Liang Wu Nov 2004

Investigation Of Pulse Potential-Modulated Coulometry For Co2 Detection, Hai-Chuan Wang, Bing-Liang Wu

Journal of Electrochemistry

A pulse potential-modulated technique was applied to measure the concentration of CO2 in gas samples. In the first step, an anodic pulse and a consequent cathodic pulse were used to remove the organic pollutant and surface oxide on the surface of the platinized Pt gauze electrode before each experiment. As following, a given potential step was used to reduce the CO2 into adsorbed intermediate on Pt surface, and the adsorbates produced were oxidized by a following anodic potential step. At same time the oxidation current of adsorbates were measured. A certain relation exists between the concentration of CO …

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The Investigation Of Bafesi/C Alloy Composite As Anode Materials For Li-Ion Battery, Rui-Xiang Feng, Hua Dong, Xin-Ping Ai, Han-Xi Yang Nov 2004

The Investigation Of Bafesi/C Alloy Composite As Anode Materials For Li-Ion Battery, Rui-Xiang Feng, Hua Dong, Xin-Ping Ai, Han-Xi Yang

Journal of Electrochemistry

A novel BaFeSi/C composite was prepared by mechanical ball milling, and lithium insertion reactions on the composite electrode were investigated by cyclic voltammetry , charge-discharge measurements, XRD and XPS spectroscopy. It is demonstrated that the capacity retention with indiscernible capacity decas during charge-discharge cycling. The improved cycling ability of the composite is suggested from a cooperative action by inactive FeSi2 and BaSi2 matrix and outer graphite shell, which both buffer the volumetric changes of the active Si phase and provide a good connection for electronic and ionic conduction during lithium insertion and extraction processes.

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Electrochemical Behavior Of Aluminized Steel In Seawater Environment, Cheng-Hao Liang, Jun Wei, Si Lu, Run-Fen Zheng Nov 2004

Electrochemical Behavior Of Aluminized Steel In Seawater Environment, Cheng-Hao Liang, Jun Wei, Si Lu, Run-Fen Zheng

Journal of Electrochemistry

The electrochemical behavior of aluminized steel in seawater has been studied by immersion test and electrochemical technology. The results indicate that compared with 20# steel, the aluminized steel has lower corrosion potential and stronger anodic activity in seawater. Its anodic solution will occur at low potential. The immersion test shows that the corrosion rates of aluminized steel and 20# steel are 5.80 mg/dm2 dand 3.36 mg/dm2 d, respectively. Through the X-ray diffraction patternanalysis, it was found that chloride ions exit in the corrosion products of aluminized steel. It proves the participation of chloride ions in the process of …

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The Inhibition Synergistic Effect Between Imidazoline Derivative And Thiourea, Jing-Mao Zhao, He-Xia Liu, Wei Di, Yu Zuo Nov 2004

The Inhibition Synergistic Effect Between Imidazoline Derivative And Thiourea, Jing-Mao Zhao, He-Xia Liu, Wei Di, Yu Zuo

Journal of Electrochemistry

The inhibition synergistic effect between imidazoline and thiourea for carbon steel in CO2 saturated brine solution was investigated by using weight-loss method, polarization curves measureament and XPS. The results showd that the inhibition efficiency increased significantly when imidazoline derivative was added as a corrosion inhibitor in the solution together with thiourea. The N and S atoms in the inhibitor film adsorbed on the surface of carbon steel, and N atoms predominated in the film near the solution and decreased gradually with the film depth and finally S atoms were the major element in the film near the matrix. It …

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Concurrent Oh Imager And Sodiumtemperature/Wind Lidar Observation Of A Mesopause Region Undular Bore Event Over Fort Collins/Platteville, Co, C. Y. She, T. Li, B. P. Williams, Tao Yuan, R. H. Picard Nov 2004

Concurrent Oh Imager And Sodiumtemperature/Wind Lidar Observation Of A Mesopause Region Undular Bore Event Over Fort Collins/Platteville, Co, C. Y. She, T. Li, B. P. Williams, Tao Yuan, R. H. Picard

All Physics Faculty Publications

We reported the observation of a mesospheric front with the properties of an undular bore by an OH imager, over the Fort Collins/Platteville area on 6/7 October 2002. Unlike the earlier bore observations, a Na lidar capable of measuring mesopause region temperature, zonal, and meridional winds was in operation concurrently. The lidar data confirm, for the first time, the existence of a collocated temperature inversion layer to serve as the ducting region for bore propagation, as required by the simple theory proposed by Dewan and Picard 6 years ago. In addition, the lidar data in principle provide sufficient information for …

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Analysis Of Process Controls In Land Surface Hydrological Cycle Over The Continental United States, Tajdarul Hassan Syed, Venkataraman Lakshmi, Evan Paleologos, Dag Lohmann, Kenneth Mitchell, James S. Famiglietti Nov 2004

Analysis Of Process Controls In Land Surface Hydrological Cycle Over The Continental United States, Tajdarul Hassan Syed, Venkataraman Lakshmi, Evan Paleologos, Dag Lohmann, Kenneth Mitchell, James S. Famiglietti

Faculty Publications

The paper uses two years (1997–1999) of data from the North American Land Data Assimilation System at National Centers for Environmental Prediction to analyze the variability of physical variables contributing to the hydrological cycle over the conterminous United States. The five hydrological variables considered in this study are precipitation, top layer soil moisture (0–10 cm), total soil moisture (0–200 cm), runoff, and potential evaporation. There are two specific analyses carried out in this paper. In the first case the principal components of the hydrological cycle are examined with respect to the loadings of the individual variables. This helps to ascertain …

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Search For Doubly Charged Higgs Bosons Decaying To Dileptons In Pp̅ Collisions At √S =1:96 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Nov 2004

Search For Doubly Charged Higgs Bosons Decaying To Dileptons In Pp̅ Collisions At √S =1:96 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

We present the results of a search for doubly charged Higgs bosons (H±±) decaying to dileptons (ll′ ) using ≈240 pb-1 of pp̅ collision data collected by the CDF II experiment at the Fermilab Tevatron. In our search region, given by same-sign ll′ mass mll′ >80 GeV/c2 (100 GeV/c2 for ee channel), we observe no evidence for H±± production. We set limits on σ (pp̅→ H++H--→l+l+l-l-) as a function of the mass of the H±± …

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Survival Analysis Using Auxiliary Variables Via Nonparametric Multiple Imputation, Chiu-Hsieh Hsu, Jeremy Taylor, Susan Murray, Daniel Commenges Nov 2004

Survival Analysis Using Auxiliary Variables Via Nonparametric Multiple Imputation, Chiu-Hsieh Hsu, Jeremy Taylor, Susan Murray, Daniel Commenges

The University of Michigan Department of Biostatistics Working Paper Series

We develop an approach, based on multiple imputation, that estimates the marginal survival distribution in survival analysis using auxiliary variable to recover information for censored observations. To conduct the imputation, we use two working survival model to define the nearest neighbor imputing risk set. One model is for the event times and the other for the censoring times. Based on the imputing risk set, two nonparametric multiple imputation methods are considered: risk set imputation, and Kaplan-Meier estimator. For both methods a future event or censoring time is imputed for each censored observation. With a categorical auxiliary variable, we show that …

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