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Analysis of CH_(4) and H_(2) Adsorption on Heterogeneous Shale Surfaces Using aMolecular Dynamics Approach
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作者 Surajudeen Sikiru Hassan Soleimani +2 位作者 Amir Rostami Mohammed Falalu Hamza Lukmon Owolabi Afolabi 《Fluid Dynamics & Materials Processing》 EI 2024年第1期31-44,共14页
Determining the adsorption of shale gas on complex surfaces remains a challenge in molecular simulation studies.Difficulties essentially stem from the need to create a realistic shale structure model in terms of miner... Determining the adsorption of shale gas on complex surfaces remains a challenge in molecular simulation studies.Difficulties essentially stem from the need to create a realistic shale structure model in terms of mineral heterogeneityand multiplicity.Moreover,precise characterization of the competitive adsorption of hydrogen andmethane in shale generally requires the experimental determination of the related adsorptive capacity.In thisstudy,the adsorption of adsorbates,methane(CH_(4)),and hydrogen(H_(2))on heterogeneous shale surface modelsof Kaolinite,Orthoclase,Muscovite,Mica,C_(60),and Butane has been simulated in the frame of a moleculardynamic’s numerical technique.The results show that these behaviors are influenced by pressure and potentialenergy.On increasing the pressure from 500 to 2000 psi,the sorption effect for CH_(4)significantly increasesbut shows a decline at a certain stage(if compared to H_(2)).The research findings also indicate that raw shalehas a higher capacity to adsorb CH_(4)compared to hydrogen.However,in shale,this difference is negligible. 展开更多
关键词 Shale gas ADSORPTION METHANE hydrogen molecular dynamic SORPTION
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Physical Activation of Elderly and the Decrease of Falling Risk
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作者 Martha Ornelas Verónica Benavides +2 位作者 Juan F. Aguirre Gabriel Gastélum Judith M. Rodríguez-Villalobos 《Health》 2014年第11期1116-1123,共8页
A Physical Activation Program was designed and implemented with a particular emphasis in recovering of motor independence, and in an indirect manner;the increase of activities was carried out in a social context in su... A Physical Activation Program was designed and implemented with a particular emphasis in recovering of motor independence, and in an indirect manner;the increase of activities was carried out in a social context in such a way that it allowed isolated elderly to develop their ability to perform daily activities diminishing the burden on their caregivers. 30 people were randomly selected: 15 subjects in the experimental group and 15 in the control group;7 women and 8 men each group. Subjects aged between 60 - 84 years with a mean age of 78 years and a standard deviation of 6.5 were applied in a three-month Physical Activation Program with a 45-min daily sessions. Results obtained showed that physical activity in elderly, systematically improved their amplitude and joint mobility which impact directly and indirectly their quality of life, reducing their risk of falling. 展开更多
关键词 Physical Activation OLDER ADULT RISK of FALLING Joint Mobility
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Diagnosis of the Physical Area of Community-Dwelling Adults
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作者 Judith Margarita Rodríguez-Villalobos Martha Ornelas Contreras +2 位作者 José René Blanco Ornelas Gabriel Gastélum Cuadras Cynthia Vannesa Gibbs Celis 《Advances in Aging Research》 2014年第5期388-393,共6页
A situational analysis of aspects related to the physical area of elderly residents of permanent stay of the city of Chihuahua was performed. Participating in the study 51 subjects, 30 women and 21 men, Tinetti and tr... A situational analysis of aspects related to the physical area of elderly residents of permanent stay of the city of Chihuahua was performed. Participating in the study 51 subjects, 30 women and 21 men, Tinetti and trunk flexion EUROFIT scales were applied to assess fall risk and range of motion. The poor results in balance, gait and range of motion can be stated that most of them are in serious risk of falling. The results obtained show the urgency of starting a physical activation program that emphasizes directly in recovery mobile independence so that enable seniors asylees enhance your ability to perform activities of daily life and reduce the burden on their caregivers. 展开更多
关键词 SITUATION Assessment ELDERLY PHYSICAL Area FALL Risk
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Profiling the effects of microwave-assisted and soxhlet extraction techniques on the physicochemical attributes of Moringa oleifera seed oil and proteins
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作者 Ngozi Maryann Nebolisa Chukwuebuka Emmanuel Umeyor +2 位作者 Uchenna Eunice Ekpunobi Immaculeta Chikamnele Umeyor Festus Basden Okoye 《Oil Crop Science》 CSCD 2023年第1期16-26,共11页
There is a constant search for biomaterials from natural products like plants for food and industrial applications.The work embodied in this report aimed at investigating the effects of microwave-assisted and soxhlet ... There is a constant search for biomaterials from natural products like plants for food and industrial applications.The work embodied in this report aimed at investigating the effects of microwave-assisted and soxhlet extraction(MAE and SE) techniques on the functional physicochemical quality characteristics of Moringa oleifera seed oil and proteins extracts. M. oleifera seeds were ground to fine powders and oil was extracted by microwave-assisted and soxhlet extraction techniques using petroleum ether. Quality attributes including yield percent, moisture content,iodine, saponification, specific gravity, viscosity, p H, thiobarbituric acid, acid and peroxide values were measured. Mineral and vitamin contents, chemical/functional groups, fatty acid(FA) composition, and reducing power of the oil were evaluated. Metabolomics of protein extracted from the defatted powders were analyzed by nuclear magnetic resonance(NMR). M. oleifera oil from MAE and SE methods had good yield(34.25 ± 0.0%,28.75 ± 0.0%), low moisture content(0.008 ± 0.0%, 0.011 ± 0.0%), non-drying and unsaturated, moderately saponified, less dense(0.91 ± 0.01, 0.92 ± 0.02 g m L^(-1)), had Newtonian flow, were weakly acidic, showed good content of FAs, recorded strong potential for long shelf-life, showed stability against oxidative rancidity and enzymatic hydrolysis, had very rich deposits of micro-and macro-nutrients as well as water-soluble and lipidsoluble vitamins, and functional groups in the oil were reflective of its content of long-and medium-chain triglycerides(LCT and MCT). Monounsaturated and saturated fatty acids(MUFA and SFA) were detected and the oil has excellent ferric ion reducing power. NMR metabolomic assay revealed the presence of nine essential amino acids(EAAs) in the protein extract. MAE technique is a feasible and acceptable alternative for high throughput extraction of M. oleifera oil with high yield and excellent quality attributes. The study revealed that MAE did not impart any remarkable advantage(s) on the physicochemical properties of M. oleifera seed oil and protein compared to SE technique. 展开更多
关键词 Moringa oleifera seed Oil Microwave-assisted extraction Soxhlet extraction Quality attributes GC-MS assay Metabolomics Reducing power
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Computational Dynamics of Stagnation Point Flow of Micropolar Fluid Past Vertical Porous Plates
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作者 Ayando Timothy Ibrahim Y. Seini Musah Sulemana 《Journal of Applied Mathematics and Physics》 2023年第11期3484-3504,共21页
This work examines the flow of a micropolar fluid over a vertical porous plate at the MHD stagnation point under viscous dissipation, convective boundary conditions, and thermal radiation. The governing partial differ... This work examines the flow of a micropolar fluid over a vertical porous plate at the MHD stagnation point under viscous dissipation, convective boundary conditions, and thermal radiation. The governing partial differential equations and a set of similarity parameters were used to transform them into ordinary differential equations. The Runge-Kutta fourth-order algorithm is used in conjunction with the Newton Raphson shooting technique to numerically solve the generated self-similar equations. Results were tabulated both numerically and graphically, and examples for different controlling factors are quantitatively analyzed. According to the study, the vortex viscosity parameter (k) causes the velocity profiles to rise while the magnetic parameter, suction parameter, and radiation parameter cause them to fall. In contrast, as the flow’s suction and prandtl values rise, so do the magnetic parameter, radiation, and vortex viscosity, while the thickness of the thermal boundary layer decreases. . 展开更多
关键词 MHD Viscous Dissipation Thermal Radiation MICROROTATION Micropolar Fluid
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Sport participation and vigilance in children:Influence of different sport expertise 被引量:2
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作者 rafael ballester florentino huertas +1 位作者 enrique molina daniel sanabria 《Journal of Sport and Health Science》 SCIE 2018年第4期497-504,共8页
Purpose: The present study aimed to investigate the relationship between different types of sport expertise(externally-paced vs. self-paced sports) and vigilance performance in children by evaluating the cardiovascula... Purpose: The present study aimed to investigate the relationship between different types of sport expertise(externally-paced vs. self-paced sports) and vigilance performance in children by evaluating the cardiovascular fitness level of the participants.Methods: Three groups of children(11.0 § 0.2 years) differentiated in terms of their regular sport participation(football players, n = 20; track and field athletes, n = 20; non-athletic controls, n = 20) took part in the study. In one session, participants performed the Leger Multi-stage fitness test to estimate their aerobic fitness level. In another session, participants completed the Psychomotor Vigilance Task(PVT) to evaluate their vigilance performance under 2 conditions of velocity demands(normal vs. speed).Results: The results revealed that both groups of sport practitioners had higher cardiovascular fitness than non-athlete controls. In contrast, no significant differences in the performance PVT were found between track and field athletes and controls. Crucially, football players showed better performance in the PVT than track and field athletes and controls. These between-group differences were not modulated by the speed demands of the task.Conclusion: The major novel finding of this research points to a positive relationship between sport participation and vigilance performance during childhood. We discuss our results in terms of the different hypotheses put forward in the literature to explain the relationship between regular exercise and cognitive functioning: the "cardiovascular fitness" and the "cognitive component skills" hypotheses. 展开更多
关键词 运动员 专家知识 警戒 孩子 健康水平 心血管 健康测试 上海大学
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Performance of La_(1-x)Sr_xCr_(1-y)Mn_yO_(3-δ) anode materials for intermediate temperature solid oxide fuel cell 被引量:2
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作者 陈秀华 马文会 +1 位作者 杨斌 戴永年 《中国有色金属学会会刊:英文版》 CSCD 2007年第A02期998-1001,共4页
La1-xSrxCr1-yMnyO3-δ(LSCM) anode materials were synthesized by glycine nitrate process(GNP). Thermo-gravimetric analysis(TGA) and differential scanning calorimetric(DSC) methods were adopted to investigate the reacti... La1-xSrxCr1-yMnyO3-δ(LSCM) anode materials were synthesized by glycine nitrate process(GNP). Thermo-gravimetric analysis(TGA) and differential scanning calorimetric(DSC) methods were adopted to investigate the reaction process of LSCM anode materials. The oxides prepared were characterized via X-ray diffraction(XRD),scanning electron microscope and energy dispersive spectroscopy(SEM-EDS),direct current four-electrode and temperature process reduction(TPR) techniques. XRD patterns indicate that perovskite phase created after the precursor was sintered at 1 000 ℃ for 5 h,and single perovskite-type oxides formed after the precursor were sintered at 1 200 ℃ for 5 h. The powders are micrometer size after sintering at 1 000 ℃ and 1 200 ℃,respectively. The conductivities of LSCM samples increase linearly with increasing the temperature from 250 ℃ to 850 ℃ in air and the maximum value is 32 S/cm for La0.7Sr0.3Cr0.5Mn0.5O3-δ. But it is lower about two orders of magnitude in pure hydrogen or methane than that of the same sample in the air. TPR result indicates that LSCM offers excellently catalytic performance. 展开更多
关键词 常温固体氧化物燃料电池 阳极材料 甘氨酸 硝化
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Trace and rare earth element geochemistry of the black and grey shales of the Calabar Flank, Southeastern Nigeria: constraints on the depositional environment and the degree of metal enrichment 被引量:1
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作者 Christopher Iorfa Adamu Benjamin Odey Omang +2 位作者 Oluwaseye Peter Oyetade Otu Johnson Therese Ntonzi Nganje 《Acta Geochimica》 EI CAS CSCD 2021年第3期312-324,共13页
This study focuses on the trace and rare earth elements(REE)geochemistry of the Nkporo and Ekenkpon Shales of the Calabar Flank.The main aim is to infer their depositional environment and the degree of their metal enr... This study focuses on the trace and rare earth elements(REE)geochemistry of the Nkporo and Ekenkpon Shales of the Calabar Flank.The main aim is to infer their depositional environment and the degree of their metal enrichment.The shale samples were analyzed using inductively coupled plasma mass spectrometry.The results indicated that the mean concentrations of K,Na,and Fe in Nkporo and Ekenkpon Shales are 1.45,0.4,and 4.17 wt%,and 1.11,0.44,and 5.42 wt%;respectively.The Nkporo Shale is enriched with the following trace elements;P>Mn>Sr>Ba>Zn>Ce>Rb>Zr>V>Cr>Ni and depleted in the following trace elements;Ta>Ge>Sb>Bi>Cd>Ag>Te>In>Hg.While the Ekenkpon Shale is enriched with the following trace elements;P>Mn>Ba>Sr>V>Ce>Zr>Rb>Cr>Zn>Ni and depleted in;Sb>Ge>Bi>Ag>Ce>Te>In>Hg.The concentration of redox-sensitive elements such as V,Ni,Mo,U,Cu,Cr,Re,Cd,Sb,Ti,Mn,and their ratio V/Mo and U/Mo in the black and grey shale samples show different patterns.The REE obtained from the Nkporo and Ekenkpon Shales were PAAS normalized.The Nkporo Shale showed a slightly flat light rare-earth element(LREE),middle rare-earth element(MREE),and heavy rare earth element(HREE)pattern enrichment.Ce/Ce*ranges from 0.95 to 1.09 in Nkporo Shale and 0.67 to 1.40 in Ekenkpon Shale.The Ekenkpon Shale showed a slight LREE,MREE enrichment,and depleted HREE patterns.The Mn contents and U/Mo ratio in Nkporo and Ekenkpon Shales suggests a poor oxygen transitional environment.The V/Mo and V/(V+Ni)ratios indicated that the Nkporo shales were deposited in an anoxic to suboxic conditions and Ekenkpon shales were also deposited under an anoxic to suboxic conditions.The V/Ni ratio indicated that the organic matter in the Nkporo shale is terrigenous while that of the Ekenkpon shales are both terrigenous and marine in origin. 展开更多
关键词 Rare-earth elements(REE) Trace elements Calabar Flank SUBOXIC ANOXIC
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Calcium and phosphorus contents of body parts of some domestic animals used as meat source in Nigeria 被引量:1
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作者 Edith U Ebeledike Godwin IC Nwokedi +2 位作者 Okechukwu O Ndu Festus BC Okoye Izuchukwu S Ochiogu 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2010年第5期395-398,共4页
Objective:To investigate the calcium and phosphorus contents of four domestic animals used as sources of meat in Nigeria.Methods:The calcium contents of the body parts of the animals were determined using atomic absor... Objective:To investigate the calcium and phosphorus contents of four domestic animals used as sources of meat in Nigeria.Methods:The calcium contents of the body parts of the animals were determined using atomic absorption spectrometer.Their phosphorus contents were determined colorimetrically using the molybdenum blue method.Results:The calcium and phosphorus contents were significantly higher in the bone samples than in the other animal parts investigated (P【0.05).The calcium contents of all the edible parts were higher in chicken than in the other animals.High calcium and phosphorus contents were detected in the faeces of chicken and goat, and that of cattle and goat,respectively.Low calcium and phosphorus contents were detected in the urine samples.Calcium:phosphorus ratios calculated for the bones of chicken,cattle and goat were satisfactory.Conclusions:In conclusion,calcium and phosphorus contents of the animal parts vary significantly and their relative contents may be related to the animal’s diet.Chicken parts may be the preferred dietary source of these minerals.This study highlights the need for routine investigation of the mineral contents of food,which is necessary for proper nutritional guidelines. 展开更多
关键词 CALCIUM Phosphorus Domestic ANIMALS ATOMIC absorption SPECTROMETER
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Adsorption Isotherms and Kinetic Studies of Congo-Red Removal from Waste Water Using Activated Carbon Prepared from Jujube Seed 被引量:1
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作者 Idris Aminu Sani M. Gumel +1 位作者 Wasila A. Ahmad Adamu A. Idris 《American Journal of Analytical Chemistry》 2020年第1期47-59,共13页
In this study, adsorption of Congo red dye onto activated carbon prepared from Jujube (Ziziphus Mauritiania) seeds with phosphoric acid as the activating agent was investigated. Batch adsorption studies were carried o... In this study, adsorption of Congo red dye onto activated carbon prepared from Jujube (Ziziphus Mauritiania) seeds with phosphoric acid as the activating agent was investigated. Batch adsorption studies were carried out to study the influence of contact time, adsorbent dosage and initial dye concentration on the adsorption. The data was analysed using pseudo-first order and pseudo-second order kinetic models. The pseudo-second order kinetic model was found to describe the adsorption more effectively with a perfect correlation coefficient of unity. The rate constant, K was obtained as 0.182 (g/mg min) and the calculated qe (9.81) is very close to the experimental value (9.78). A high correlation coefficient obtained when the data was analysed with the intraparticle diffusion rate equation, revealed the presence of intraparticle diffusion in the adsorption process even though it is not the sole controlling step as shown by the value of the intercept (C ≠ 0). Isotherm studies showed that there is high correlation in each case when the data was modelled with Langmuir, Freundlich, Temkin and Dubinin-Radushkevic isotherm models but the best fit was obtained with the Freundlich model with R2 = 0.9991, adsorption capacity, KF = 19.73 (mg/g)(mg/L)1/n and n = 1.563 indicating the adsorption is favourable and occurs on a heterogeneous surface by multilayer. The study showed that activated carbon from jujube seeds is an effective adsorbent for the removal of Congo red dye from solution. 展开更多
关键词 Adsorption Kinetics Isotherms JUJUBE SEEDS CONGO Red
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Investigating Contributions of Total Column Ozone Variation on Some Meteorological Parameters in Nigeria 被引量:1
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作者 Eucharia Chidinma Okoro Francisca Nneka Okeke Lilian Chinenyenwa Omeje 《Atmospheric and Climate Sciences》 2022年第1期132-149,共18页
The relationship between some meteorological parameters and variation of total column ozone (TCO) concentration in Nigeria is studied from 1998-2012<span style="font-family:Verdana;">. The results usin... The relationship between some meteorological parameters and variation of total column ozone (TCO) concentration in Nigeria is studied from 1998-2012<span style="font-family:Verdana;">. The results using a descriptive analysis revealed a seasonal ozone variation having the same trend in all the stations during the period of study. High variability of TCO occurred between December and March coinciding with the period of dry season and low variability of TCO was observed in August coinciding with the period of rainy season. The observed trends in all the stations show that the TCO variation in Nigeria is mostly caused by natural occurrences. Calabar and Port Harcourt stations showed a high percent of TCO variability, while Kano and Maiduguri indicated a low percentage of TCO variability. Using Spearman correlation analysis, TCO concentration has a strong negative correlation with temperature in some stations with correlation coefficient (r) (-</span><span style="font-family:Verdana;">0.8392, -0.8531, -0.7832, -8881 and -0.7902) for Calabar, Port</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">Harcourt, Makurdi, Lagos and Ilorin respectively. Kano and Maiduguri showed a weak positive correlation coefficient (r) 0.4965 and 0.3776 respectively. Positive correlation observed in Kano and Maiduguri could be as a result of high dehydration of water vapour in these stations due to seasonal harmattan and latitudinal effects. Probably, some of the substances that could deplete ozone such as HCl, aerosol are soluble in water thereby being washed off by rain </span><span style="font-family:Verdana;">during wet season leading to maximum TCO concentration during rainy</span><span style="font-family:Verdana;"> sea</span><span style="font-family:Verdana;">son. Consequently, the observed phenomenon is through transportation of ozone</span><span style="font-family:Verdana;"> content through the influence of Brewer-Dobson circulation. Again, during </span><span style="font-family:Verdana;">wet season, there is the mechanism of low pressure and lower tropopause height</span><span style="font-family:Verdana;"> phenomenon, therefore, total ozone enhancement. Interestingly, variation in TCO is part of symbolic tools for tropospheric meteorology alteration and this invariably leads to climate change.</span></span> 展开更多
关键词 Total Column Ozone Temperature RAINFALL SEASONAL CORRELATION
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Performance of LSCM-CDC Composite Anode for ITSOFC
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作者 马学菊 陈秀华 +1 位作者 马文会 戴永年 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S1期391-394,共4页
It was prepared by glycine-nitrate process (GNP) method for a novel composite material La0.7Sr0.3Cr0.5Mn0.5O3-δ-Ce0.8Ca0.2O2-δ (LSCM-CDC) used for anode of intermediate temperature solid oxide fuel cell (ITSOFC). Th... It was prepared by glycine-nitrate process (GNP) method for a novel composite material La0.7Sr0.3Cr0.5Mn0.5O3-δ-Ce0.8Ca0.2O2-δ (LSCM-CDC) used for anode of intermediate temperature solid oxide fuel cell (ITSOFC). The microstructure and properties of composite anode LSCM-CDC were measured via X-ray diffraction (XRD), scanning electron microscopy (SEM), AC impedance and four-probe direct current methods. Fluorite-perovskite compounded phase structure was obtained after being sintered at 1400 ℃ for 15 h, the optimum composition of the composite anode of LSCM and CDC was 7 to 3 at molar ratio. At 850 ℃, the electronic conductivity was 6.49 S·cm-1 in air and 1 S·cm-1 in the reduction atmosphere, respectively. The AC impedance spectra with two arcs showed that LSCM-CDC had low ionic conductivity, which was about two orders of magnitude lower than the electronic conductivity. LSCM-CDC composite anode was stable under different temperatures in pure methane gas with good catalytic performance, which indicated that the composite was a promising anode for ITSOFC. 展开更多
关键词 ITSOFC LSCM-CDC anode material electrical performance rare earths
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Experimental study on the characteristics of DBD plasma coal liquefaction by using coal nanopowder
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作者 Song Chol PAK Kuk Song HAN +1 位作者 Yong Jun KIM Hak Chol CHOE 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第11期86-92,共7页
A new method for liquefying coal using dielectric barrier discharge plasma has been studied.By utilizing waste oil as the solvent and processing coal nano powder in the plasma for 10 min,we have attained a liquid yiel... A new method for liquefying coal using dielectric barrier discharge plasma has been studied.By utilizing waste oil as the solvent and processing coal nano powder in the plasma for 10 min,we have attained a liquid yield of more than 80%.The experiment shows that not only the coal nanopowder promoted the liquefaction process,but hydrogen radicals improved the liquid yield effectively.In the plasma processing,the phenomenon of the changing color of the nanopowder solution and not producing a solid residue has been obviously observed.The rational parameters that affected the liquefaction of coal nanopowder have been achieved through the experiment,and the liquefied products have been analyzed. 展开更多
关键词 LIQUEFACTION DBD PLASMA COAL NANOPOWDER
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Quantum Chemistry Study on Benzimidazoledithi Derivatives' Selective Pre-enrichment of Cadmium Cation
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作者 李绍元 耿超 +4 位作者 杨子恒 杨玺 陈秀敏 陈秀华 马文会 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第12期1860-1868,1843,共10页
This work reports the mechanism of benzimidazoledithi(BDT) derivatives’ selective pre-enrichment of Cd2+under the stimulation of glutathione(GSH). The geometric and electronic properties of five BDT-M2+complexes(M = ... This work reports the mechanism of benzimidazoledithi(BDT) derivatives’ selective pre-enrichment of Cd2+under the stimulation of glutathione(GSH). The geometric and electronic properties of five BDT-M2+complexes(M = Cd, Cu, Hg, Pb, Co) have been investigated using density functional theory(DFT) at the B3 LYP/6-311 G(d,p) level with the GAUSSIAN 09 package program. The results show that BDT ligand exhibits alternative behaviors to different metal ions with the binding affinity in the order of Cu2+> Cd2+> Pb2+> Hg2+> Co2+. After adding the BDT-M2+complex into the GSH solution, the new S–S bonds can be formed, resulting with benzimidazole-metal ions(MBI-M2+) falling off into the GSH solution. Furthermore, the weak interaction between the new glutathione derivative(GSHD) and MBI-M2+were found. However, the strong chelation was detected between GSHD and MBI-M2+(M = Cu, Pb, Hg, Co) to hinder the adsorbed Cu2+, Pb2+and Hg2+, Co2+completely falling into the GSH solution, which suggests porous silicon composite modified by BDT has a certain selective pre-enrichment of Cd2+ion. 展开更多
关键词 benzimidazoledithi(BDT) derivatives selective pre-enrichment GLUTATHIONE cadmium ion density functional theory
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Comparison of Outlier Techniques Based on Simulated Data
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作者 Adaku C. Obikee Godday U. Ebuh Happiness O. Obiora-Ilouno 《Open Journal of Statistics》 2014年第7期536-561,共26页
This research work employed a simulation study to evaluate six outlier techniques: t-Statistic, Modified Z-Statistic, Cancer Outlier Profile Analysis (COPA), Outlier Sum-Statistic (OS), Outlier Robust t-Statistic (ORT... This research work employed a simulation study to evaluate six outlier techniques: t-Statistic, Modified Z-Statistic, Cancer Outlier Profile Analysis (COPA), Outlier Sum-Statistic (OS), Outlier Robust t-Statistic (ORT), and the Truncated Outlier Robust t-Statistic (TORT) with the aim of determining the technique that has a higher power of detecting and handling outliers in terms of their P-values, true positives, false positives, False Discovery Rate (FDR) and their corresponding Receiver Operating Characteristic (ROC) curves. From the result of the analysis, it was revealed that OS was the best technique followed by COPA, t, ORT, TORT and Z respectively in terms of their P-values. The result of the False Discovery Rate (FDR) shows that OS is the best technique followed by COPA, t, ORT, TORT and Z. In terms of their ROC curves, t-Statistic and OS have the largest Area under the ROC Curve (AUC) which indicates better sensitivity and specificity and is more significant followed by COPA and ORT with the equal significant AUC while Z and TORT have the least AUC which is not significant. 展开更多
关键词 Area under the ROC CURVE Reference Line Sensitivity SPECIFICITY P-VALUE False Discovery Rate (FDR) Simulation
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Statistical Comparison of Eight Alternative Methods for the Analysis of Paired Sample Data with Applications
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作者 Godday Uwawunkonye Ebuh Ikewelugo Cyprian Anaene Oyeka 《Open Journal of Statistics》 2012年第3期328-345,共18页
This paper presents and statistically compared eight alternative methods that could possibly be used in the analysis of matched or paired sample data, including situations in which the data being analyzed satisfy the ... This paper presents and statistically compared eight alternative methods that could possibly be used in the analysis of matched or paired sample data, including situations in which the data being analyzed satisfy the usual assumptions of normality and continuity necessary for the use of parametric tests as well as when the data are numeric and non-numeric measurements on as low as the ordinal scale. It is shown that only the modified sign tests based on only the raw observations or their assigned ranks may be used with non numeric measurement on the ordinal scale. If the ordinary sign test, the Wilcoxon signed rank sum test and the modified sign tests can be equally used in data analysis, then it is shown that the modified sign tests are more efficient and hence more powerful than the ordinary sign tests because the two test statistics are intrinsically and structurally modified for the possible presence of tied observations between the sampled populations for both using raw and simulated data. Of all the non-parametric methods presented, the modified Wilcoxon’s signed rank sum test when applicable is the most efficient and powerful, following in this order by the modified sign test by ranks and the modified sign test based on only raw scores for raw data but simulation, modified sign test by ranks is the most efficient and powerful, following in this order by modified wilcoxon’s signed rank sum test and modified sign test. Each of the non-parametric methods presented can be easily modified and re-specified for use with one sample data by simply re-designating the observations from one of the sampled populations to correspond with a hypothesized value of some measure of central tendency. The methods are illustrated with some raw data as well as simulated data and their relative performances compared. 展开更多
关键词 NORMALITY CONTINUITY Paired SAMPLE PARAMETRIC Test NONPARAMETRIC Numeric Relative Performance Tied Oberservation
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Situational Diagnosis of the Social Sphere of Elders Living in Retirement Homes
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作者 Verónica Benavides Pando Martha Ornelas Contreras +2 位作者 Jesús Enrique Peinado Pérez Juan Cristóbal Barrón Luján Lepoldo Refugio López Baca 《Advances in Aging Research》 2015年第2期42-46,共5页
A situational diagnosis of the social sphere of elder permanent residents at retirement homes in Chihuahua City was created with the aid of the Social Resource Scale instrument. From the 51 participants, there were 30... A situational diagnosis of the social sphere of elder permanent residents at retirement homes in Chihuahua City was created with the aid of the Social Resource Scale instrument. From the 51 participants, there were 30 female and 21 male elders. The results and conclusions of the present study highlight two major needs: a systematic assessment of permanent residents in retirement homes and the implementation of a physical activation program. The proposed physical activation program must focus on both, the recovery of motor independence and the increase of socialization activities which allows members of the retired community to improve their daily routine performance and lessens the work load on their caretakers. 展开更多
关键词 Situational DIAGNOSIS ELDER SOCIAL SPHERE
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Preliminary Investigation of Formulated Herbal Ointment Demonstrates Amelioration of Excision Wound in Experimental Rabbit Model Compared with Silver Sulfadiazine
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作者 Martin Ntiamoah Donkor Richard Mosobil +1 位作者 Abdul Wadudu Yakubu Kutub Shaibu Addai-Mensah Donkor 《Journal of Biosciences and Medicines》 CAS 2022年第12期32-41,共10页
In light of the use of Lannea barteri in the management of diverse illnesses and treatment of wounds in traditional medicine, the current study was conducted to assess the wound-healing efficacy of crude aqueous extra... In light of the use of Lannea barteri in the management of diverse illnesses and treatment of wounds in traditional medicine, the current study was conducted to assess the wound-healing efficacy of crude aqueous extract of the stem bark of Lannea barteri and its shea butter formulated ointment using an excision wound model in the rabbit. The herbal ointment (5%, w/w) exhibited a significant wound healing activity, showing 99.9% ± 0.3% wound contraction at the end of the experiment (24th day). There was no significant difference (p > 0.05) between the 5% (w/w) herbal ointment compared with Silver Sulphadiazine cream (positive control), which showed a 97.8% ± 1.0% rate of excision wound contraction on day 24. Compared with the negative control group (administered with only shea butter), the wound healing activity of the ointment was significant (p Lannea barteri for the treatment of wounds and demonstrates that shea butter usage as a base in formulating an herbal ointment might aid in topical application for wound repair and regeneration, as well as the potential for enhanced wound healing. 展开更多
关键词 Excision Wound Model Wound Healing Lannea barteri Shea Butter FORMULATION
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Investigation of the Mechanical Properties of Flexible Polyether Foam Filled with Eggshell and Groundnut Husk Powder
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作者 P.U.Chris-Okafor R.U.Arinze +1 位作者 I.M.Iloamaeke B.C.Izundu 《Organic Polymer Material Research》 2019年第2期14-19,共6页
The study investigated the effect of eggshell and groundnut husk as fillers on flexible polyether foam.The fillers with the particle sizes of 50μm each were mixed in the ratio of 50:50.Diverse percentages of the two ... The study investigated the effect of eggshell and groundnut husk as fillers on flexible polyether foam.The fillers with the particle sizes of 50μm each were mixed in the ratio of 50:50.Diverse percentages of the two combined fillers ranging from 10%,20%,30%,40%and 50%were incorporated into the polyether recipes in the appropriate foam formulations and foam samples were produced.The unfilled foam(0%filler)served as the standard control sample.The physico-mechanical test carried out on the foam showed increase in the properties such as density,compression set test,indentation hardness test,tensile strength test and decrease for elongation at break test as compared to the unfilled foam.The scanning electron microscopy result showed the cell sizes became smaller and concentrated with an irregular shape as the filler load increased,thereby making it denser and thicker.Eggshell and groundnut husk fillers may be used in the making of flexible polyether foam since these materials are organic in natures.They can improve the mechanical properties and biodegradability of polyurethane product.The utilization of these fillers in polymer composites productin will help in sanitizing the environment by reducing landfills and producing eco-friendly waste and also it influences cost positively. 展开更多
关键词 EGG shell GROUNDNUT husk POLYETHER foam Scanning electron MICROSCOPE MECHANICAL properties
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A Comparative Evaluation of Test Coverage Techniques Effectiveness
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作者 Xaveria Youh Djam Nachamada Vachaku Blamah Modesta Ero Ezema 《Journal of Software Engineering and Applications》 2021年第4期95-109,共15页
<div style="text-align:justify;"> <span style="font-family:Verdana;">Software systems have become complex and challenging to develop and maintain because of the large size of test cases... <div style="text-align:justify;"> <span style="font-family:Verdana;">Software systems have become complex and challenging to develop and maintain because of the large size of test cases with increased scalability issues. Test case prioritization methods have been successfully utilized in test case management. However, the prohibitively exorbitant cost of large test cases is now the mainstream in the software industry. The growth of agile test-driven development has increased the expectations for software quality. Yet, our knowledge of when to use various path testing criteria for cost-effectiveness is inadequate due to the inherent complexity in software testing. Existing researches attempted to address the issue without effectively tackling the scalability of large test suites to reduce time in regression testing. In order to provide a more accurate way of fault detection in software projects, we introduced novel coverage criteria, called Incremental Cluster-based test case Prioritization (ICP), and investigated its potentials by making a comparative evaluation with three un-clustered traditional coverage-based criteria: Prime-Path Coverage (PPC), Edge-Pair Coverage (EPC) and Edge Coverage (EC) based on mutation analysis. By clustering test suites, based on their dynamic run-time behavior, the number of pair-wise comparisons is reduced significantly. To compare, we analyzed 20 functions from 25 C programs, instrumented faults into the programs, and used the Mull mutation tool to generate mutants and perform a statistical analysis of the results. The experimental results show that ICP can lead to cost-effective improvements in fault detection.</span> </div> 展开更多
关键词 Software Testing Fault Detection Mutation Analysis Test Case Prioritization Control Flow Coverage
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