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STUDY oN THE PRoPERTIES oF DIFFERENT ACTIVATED CARBoN FIBERS AND THEIR ADSoRPTIoN CHARACTERISTICS FoR FoRMALDEHYDE

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 467-472页

作者： H.Q. Rong, Z.Y. Ryu and J.T. Zheng (Institute of Coal Chemistry, The Chinese Academy of Sciences, P.o.Box 165, Taiyuan 030001, China) Inst. of Coal Chem. Chinese Acad. of Sci. P.O. Box 165 Taiyuan 030001 China

Porous structure and surface chemistry of activated carbon fibers obtained by differ-ent precursors and activation methods were investigated. Adsorption isotherms werecharacterized by nitrogen adsorption at 77K over a relative pressure range from 10 6to 1. The regularization method according to Density Functional Theory (DFT) wasemployed to calculate the pore size distribution in the samples. Their specific surfaceareas were calculated by BET method, micropore volume and microporous specificsurface area calculated by t-plot method and MPD by Horvath-Kawazoe equation. Mi-cropore volume of rayon-based ACF was higher than that of other samples. The staticand dynamic adsorption capacity for formaldehyde on different ACFs was *** results show that steam activated Rayon-based A CFs had higher adsorption capac-ity than that of steam and KoH activated PAN-A CFs. Breakthrough curves illustratedthat Rayon-ACFs had longer breakthrough time, thus they possessed higher adsorp-tion capacity for formaldehyde than that of PAN-ACFs. The entire sample had smalladsorption capacity and short breakthrough time for water. Rayon-A CFs had exccl-lent adsorption selectivity for formaldehyde than PAN-ACFs. And the samples withhigh surface areas had relatively high adsorption capacity for formaldehyde. Elementaicontent of different A CFs were performed. Rayon-based A CFs contained more oxygenthan PAN-ACFs, which may be attributed to their excellent adsorption capacity forformaldehyde.

关键词： activated carbon fiber porous structure surface chemistry formaldehyde adsorption characteristic

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A Facile and Inexpensive Synthesis of 6-Ethynylbipyridine

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International Journal of organic Chemistry 2011年第2期1卷 33-36页

作者： Jianqiang Huo John o. Hoberg 不详

An inexpensive synthesis of 6-ethynylbipyridine has been accomplished using Sonogashira coupling of 2-bromo-6-iodopyridine with 2-methyl-3-butyn-2-ol. Subsequent Stille coupling with 2-(trimethylstannanyl) pyridine an... 详细信息

关键词： 6-Ethynylbipyridine 2-Bromo-6-Iodopyridine 2-Methyl-3-Butyne-2-ol Palladium Coupling

High-Performance Multipath Routing Algorithm Using CPEGASIS Protocol in Wireless Sensor Cloud Environment

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Circuits and Systems 2016年第10期7卷 3246-3252页

作者： o. Pandithurai Dr. C. Sureshkumar Anna University of Technology Comibatore India J.K.K. Nattraja College of Engineering and Technology Komarapalayam India

The current IT cloud computing is playing a vital role in most of the areas such as Education, Research, Health care, etc. The cloud computing technology involving in sensor networks embedded system and IoT (Internet of Things). At present scenario, the sensors collected the information from the particular environment, where the sensors are fixed and transfer the collected information to cloud storage, here the challenge is the data transmission i.e. data that traverse from sensor to cloud environment are the big issue and maximum number of data loss is very high especially in dynamic routing environment. If data loss is identified in any routing path then automatically the information will transfer to alternate routing path. In this paper, we introduce a new algorithm for automatic routing path selection that can be integrated with cloud technology. This algorithm supports when data loss is found in the particular path of a network, then it selects an alternate route to transfer the data. The proposed model is comparatively more efficient than the prior methodologies. The implementation of the proposed work is done on NS3 simulator, and the performance metric is analyzed.

关键词： Wireless Sensor Cloud Computing Internet of Things

Effects of Graphite Additions and Heat Treatment on the Microstructure, Mechanical and Tribological Properties of 13% Chromium White Iron

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Journal of Minerals and Materials Characterization and Engineering 2014年第4期2卷 270-285页

作者： J. o. Agunsoye S. A. Bello I. o. Awe A. A. Yekinni R. G. Adeyemo A. o. ologunagba Department of Mechanical Engineering Lagos State Polytechnic Ikorodu Nigeria Department of Metallurgical and Materials Engineering University of Lagos Lagos Nigeria Department of Metallurgical Engineering Yaba College of Technology Lagos Nigeria

A 13% chromium white iron was produced using a stir cast process. Samples of the produced white iron were austenised at 1450°C and then quenched in water to the room temperature. The characterisation tools such as X-ray diffractometer, scanning electron microscope, Brinell hardness tester and pin on disc machine were employed in the studies of the phase orientation and morphology, hardness value measurement and investigation of wear behaviour. The results revealed that water quenching the 13% chromium white iron led to the precipitation of fine iron chromides and cementite in the matrix of martensite. Moreover, there is an about 22% to 45% increase in hardness values of the as-cast 13% chromium white iron as the %composition of graphite additions increased from 1.36 to 3.04. However, the impact energy values are sacrificed. The increase in hardness values is attributable to hard intermetallic compounds such as iron chromides and cementite phases in the iron matrix. Also, there is an about 32% - 42% increase in hardness values of the heat treated samples of 13% chromium white iron when compared with those of the as-cast. The increased hardness values are attributable to even distribution of the fine intermetallic compounds in the fine grains of martensitic matrix. The wear rate increased as the sliding moments per unit time increased due to increasing work done by the friction to oppose the rotation of the pin on disc. The water quenched 13% chromium white iron samples have greater wear resistances than the as-cast samples due to their greater hardness values than those of the as-cast samples. The effect of speed increase on decreasing wear resistances is more pronounced on the heat treated samples than on the as-cast samples. Hence, the water quenched 13% chromium white iron is an excellent material in application requiring high wear resistance and low impact energy especially in grinding mill liner plate, bottom or casing used in the concrete pipe production, rolle

关键词： 13% Chromium White Iron Water Quench Microstructure Mechanical Properties Tribological

Pain sensation in pancreatic diseases is not uniform: The different facets of pancreatic pain

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World Journal of Gastroenterology 2014年第27期20卷 9154-9161页

作者： Jan G D'Haese Mark Hartel Ihsan Ekin Demir Ulf Hinz Frank Bergmann Markus W Büchler Helmut Friess Güralp o Ceyhan Department of Surgery Klinikum Rechts der Isar Technische Universit?t München Unit for Documentation and Statistics Department of General Surgery University of Heidelberg Institute of Pathology University of Heidelberg Department of General Surgery University of Heidelberg

AIM: To systematically characterize specific pain patterns in the most frequent pancreatic diseases.

关键词： Abdominal pain Pancreatic neoplasm Chronic pancreatitis Intraductal papillary mucinous neoplasia Pancreatic cancer

Accuracy of two optical chlorophyll meters in predicting chemical composition and in vitro ruminal organic matter degradability of Brachiaria hybrid,Megathyrsus maximus, and Paspalum atratum

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Animal Nutrition 2017年第1期3卷 67-76页

作者： Martin P.Hughes Victor Mlambo Cicero H.o.Lallo Nasreldin A.D.Basha Ignatius V.Nsahlai Paul G.A.Jennings Department of Food Production Faculty of Food and AgricultureUniversity of the West Indies Department of Animal Science School of Agricultural SciencesFaculty of AgricultureScience and TechnologyNorth-West University open Tropical Forage-Animal Production Laboratory Department of Food ProductionFaculty of Food and AgricultureUniversity of the West Indies Department of Animal & Poultry Science School of AgriculturalEarth and Environmental SciencesCollege of AgricultureEngineering and ScienceUniversity of KwaZulu-Natal Department of Animal Nutrition Faculty of Animal Production Shampat CampusUniversity of Khartoum MARJEN Consulting Group

The objective of this study was to determine the accuracy and reliability of 2 optical chlorophyll meters:FieldScout CM 1,000 NDVI and Yara N-Tester, in predicting neutral detergent fibre(NDF), acid detergent fibre(ADF), acid detergent lignin(ADL), acid detergent insoluble nitrogen(ADIN) and in vitro ruminal organic matter degradability(IVoMD) of 3 tropical grasses. optical chlorophyll measurements were taken at 3 stages(4, 8 and 12 weeks) of regrowth in Brachiaria hybrid, and Megathyrsus maximus and at 6 and 12 weeks of regrowth in Paspalum atratum(cv. Ubon). optical chlorophyll measurements showed the highest correlation(r = 0.57 to 0.85) with NDF concentration. The FieldScout CM 1,000 NDVI was better than the Yara N-Tester in predicting NDF(R^2 = 0.70) and ADF(R^2 = 0.79) concentrations in Brachiaria hybrid and NDF(R^2 = 0.79) in M. maximus. Similarly, FieldScout CM 1,000 NDVI produced better estimates of 24 h IVoMD(IVoMD_(24 h)) in Brachiaria hybrid(R^2 = 0.81) and IVoMD_(48 h) in Brachiaria hybrid(R^2 = 0.65) and M. maximus(R^2 = 0.75). However, these prediction models had relatively low concordance correlation coefficients, i.e., CCC >0.90, but random errors were the main source of bias. It was,therefore, concluded that both optical chlorophyll meters were poor and unreliable predictors of ADIN and ADL concentrations. overall, the FieldScout CM 1,000 NDVI shows potential to produce useful estimates of IVoMD_(24h) and ADF in Brachiaria hybrid and IVoMD_(48 h) and NDF concentrations in M. maximus.

关键词： optical chlorophyll measurements Chemical composition Prediction model Tropical grass

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Preventing Behavioral-Risks Incidence among School Children: The Role of School-Based Health Promotion Program

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Journal of Biosciences and Medicines 2021年第8期9卷 155-169页

作者： Raymond o. Chimezie Marychristiana E. Uzochukwu Health for Schools & Community Foundation Richmond USA School of Nursing College of Health and Human Sciences North Carolina A&T State University Greensboro USA

This article addresses the important role school health education program can play in reducing youth risky behaviors that lead to incarceration, diseases and fatalities or that impact their academic performance in school. Children growing up are at risks of exposure to different behaviors and common social influences which if unchecked result in unexpected health consequences common among youth in America today. According to US Centers for Disease Control & Prevention, the six leading behaviors that cause death, disability, and social problems among American children are: unintentional injuries and violence, alcohol and drug use, tobacco use, unhealthy diets, inadequate physical activities, and sexual behaviors and diseases. This article shows that school health program: 1) can provide the foundation for children to learn desired healthy behaviors in order to preserve life, 2) protects the future of children and that of the nation, 3) can teach students skills to recognize risky behaviors and resist them, 4) can boost community efforts to achieve desired health behaviors, 5) closes socio-economic gaps that interfere with basic nurturing of children, and 6) finally links local stakeholders as partners in promoting community safety. Through review of literature, the authors found that it costs ($588) daily or (214,620) annually to incarcerate a juvenile and only $75 daily for the cost of individualized community-based services. The cost to New York is over $900,000, yet does not address the causative issues. The authors recommend that schools teach comprehensive school health from kindergarten to grade 12 and employ health educators to support teachers teach health promotion and education.

关键词： School Health Health Promotion Youth Health Youth Behavioral Risk-Factors Health Education Comprehensive School Health

Xylanase, protease and superdosing phytase interactions in broiler performance, carcass yield and digesta transit time

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Animal Nutrition 2017年第2期3卷 121-126页

作者： Tiago T.dos Santos Helen V.Masey o'Neill Gemma González-ortiz Daniel Camacho-Fernández Carlos López-Coello AB Vista Facultad de Medicina Veteriaria y Zootecnia Universidad Nacional Autónoma de México

The interaction of xylanase, protease and superdosing(1,500 FTU/kg) phytase in a 2×2×2 factorial arrangement was studied in broilers fed sorghum-based diets. A total of 2,800 one-day-old unsexed Ross308 chicks were housed in 56 pens with 50 birds per pen, with or without inclusion of xylanase, protease and phytase, totaling 8 treatments and 7 replicates per treatment. Body weight(BW) and feed intake(FI)were measured at 21 and 42 days of age, and mortality corrected feed conversion ratio(FCR) was calculated for each period and cumulatively. Tibia ash and carcass yield were determined in 2 birds per replicate at 21 and 42 days of age, respectively. Digesta transit time was determined at 21, 28, 35 and 42 days of age using 5 birds per replicate. Results showed that superdosing phytase increased BW and FI at42 days of age(P oved FCR(P o positively influenced carcass yield and breast weight, respectively. overall, inclusion of superdosing phytase increased transit time when included in a diet containing xylanase, and no change with protease inclusion. In conclusion, the beneficial effects of xylanase, protease and superdosing phytase in broiler performance were not additive. This limitation is likely not related to the lack of efficacy of any one of the individual enzymes but to a limitation of the bird to respond additively to successive additions of enzymes.

关键词： Sorghum Tibia ash Sub-additivity Exogenous enzyme

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on Sample Size Determination When Comparing Two Independent Spearman or Kendall Coefficients

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open Journal of Statistics 2022年第2期12卷 291-302页

作者： Justine o. May Stephen W. Looney Health System Information Technology Augusta University Augusta USA Department of Population Health Sciences Augusta University Augusta USA

one of the most commonly used statistical methods is bivariate correlation analysis. However, it is usually the case that little or no attention is given to power and sample size considerations when planning a study in which correlation will be the primary analysis. In fact, when we reviewed studies published in clinical research journals in 2014, we found that none of the 111 articles that presented results of correlation analyses included a sample size justification. It is sometimes of interest to compare two correlation coefficients between independent groups. For example, one may wish to compare diabetics and non-diabetics in terms of the correlation of systolic blood pressure with age. Tools for performing power and sample size calculations for the comparison of two independent Pearson correlation coefficients are widely available;however, we were unable to identify any easily accessible tools for power and sample size calculations when comparing two independent Spearman rank correlation coefficients or two independent Kendall coefficients of concordance. In this article, we provide formulas and charts that can be used to calculate the sample size that is needed when testing the hypothesis that two independent Spearman or Kendall coefficients are equal.

关键词： Fisher z-Transform Hypothesis Testing Power Significance Level