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Search Results: 1 - 10 of 10514 matches for " Long GB "
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Facile one-step coating approach to magnetic submicron particles with poly(ethylene glycol) coats and abundant accessible carboxyl groups
Long GB,Yang XL,Zhang Y,Pu J
International Journal of Nanomedicine , 2013,
Abstract: Gaobo Long,1,* Xiao-lan Yang,1,* Yi Zhang,1 Jun Pu,2 Lin Liu,1 Hong-bo Liu,1 Yuan-li Li,1 Fei Liao11Unit for Analytical Probes and Protein Biotechnology, Key Laboratory of Clinical Laboratory Diagnostics of the Education Ministry, College of Laboratory Medicine, 2Department of Urology, the First Affiliated Hospital, Chongqing Medical University, Chongqing, People's Republic of China*These authors contributed equally to this workPurpose: Magnetic submicron particles (MSPs) are pivotal biomaterials for magnetic separations in bioanalyses, but their preparation remains a technical challenge. In this report, a facile one-step coating approach to MSPs suitable for magnetic separations was investigated.Methods: Poly(ethylene glycol) (PEG) was derived into PEG-bis-(maleic monoester) and maleic monoester-PEG-succinic monoester as the monomers. Magnetofluids were prepared via chemical co-precipitation and dispersion with the monomers. MSPs were prepared via one-step coating of magnetofluids in a water-in-oil microemulsion system of aerosol-OT and heptane by radical co-polymerization of such monomers.Results: The resulting MSPs contained abundant carboxyl groups, exhibited negligible nonspecific adsorption of common substances and excellent suspension stability, appeared as irregular particles by electronic microscopy, and had submicron sizes of broad distribution by laser scattering. Saturation magnetizations and average particle sizes were affected mainly by the quantities of monomers used for coating magnetofluids, and steric hindrance around carboxyl groups was alleviated by the use of longer monomers of one polymerizable bond for coating. After optimizations, MSPs bearing saturation magnetizations over 46 emu/g, average sizes of 0.32 μm, and titrated carboxyl groups of about 0.21 mmol/g were obtained. After the activation of carboxyl groups on MSPs into N-hydroxysuccinimide ester, biotin was immobilized on MSPs and the resulting biotin-functionalized MSPs isolated the conjugate of streptavidin and alkaline phosphatase at about 2.1 mg/g MSPs; streptavidin was immobilized at about 10 mg/g MSPs and retained 81% ± 18% (n = 5) of the specific activity of the free form.Conclusion: The facile approach effectively prepares MSPs for magnetic separations.Keywords: magnetic submicron particles, carboxyl groups, PEG-bis-(maleic monoester), monomer, radical co-polymerization, steric hindrance
Facile one-step coating approach to magnetic submicron particles with poly(ethylene glycol) coats and abundant accessible carboxyl groups
Long GB, Yang XL, Zhang Y, Pu J, Liu L, Liu HB, Li YL, Liao F
International Journal of Nanomedicine , 2013, DOI: http://dx.doi.org/10.2147/IJN.S41411
Abstract: cile one-step coating approach to magnetic submicron particles with poly(ethylene glycol) coats and abundant accessible carboxyl groups Original Research (601) Total Article Views Authors: Long GB, Yang XL, Zhang Y, Pu J, Liu L, Liu HB, Li YL, Liao F Published Date February 2013 Volume 2013:8 Pages 791 - 807 DOI: http://dx.doi.org/10.2147/IJN.S41411 Received: 11 December 2012 Accepted: 10 January 2013 Published: 25 February 2013 Gaobo Long,1,* Xiao-lan Yang,1,* Yi Zhang,1 Jun Pu,2 Lin Liu,1 Hong-bo Liu,1 Yuan-li Li,1 Fei Liao1 1Unit for Analytical Probes and Protein Biotechnology, Key Laboratory of Clinical Laboratory Diagnostics of the Education Ministry, College of Laboratory Medicine, 2Department of Urology, the First Affiliated Hospital, Chongqing Medical University, Chongqing, People's Republic of China *These authors contributed equally to this work Purpose: Magnetic submicron particles (MSPs) are pivotal biomaterials for magnetic separations in bioanalyses, but their preparation remains a technical challenge. In this report, a facile one-step coating approach to MSPs suitable for magnetic separations was investigated. Methods: Poly(ethylene glycol) (PEG) was derived into PEG-bis-(maleic monoester) and maleic monoester-PEG-succinic monoester as the monomers. Magnetofluids were prepared via chemical co-precipitation and dispersion with the monomers. MSPs were prepared via one-step coating of magnetofluids in a water-in-oil microemulsion system of aerosol-OT and heptane by radical co-polymerization of such monomers. Results: The resulting MSPs contained abundant carboxyl groups, exhibited negligible nonspecific adsorption of common substances and excellent suspension stability, appeared as irregular particles by electronic microscopy, and had submicron sizes of broad distribution by laser scattering. Saturation magnetizations and average particle sizes were affected mainly by the quantities of monomers used for coating magnetofluids, and steric hindrance around carboxyl groups was alleviated by the use of longer monomers of one polymerizable bond for coating. After optimizations, MSPs bearing saturation magnetizations over 46 emu/g, average sizes of 0.32 μm, and titrated carboxyl groups of about 0.21 mmol/g were obtained. After the activation of carboxyl groups on MSPs into N-hydroxysuccinimide ester, biotin was immobilized on MSPs and the resulting biotin-functionalized MSPs isolated the conjugate of streptavidin and alkaline phosphatase at about 2.1 mg/g MSPs; streptavidin was immobilized at about 10 mg/g MSPs and retained 81% ± 18% (n = 5) of the specific activity of the free form. Conclusion: The facile approach effectively prepares MSPs for magnetic separations.
Morpho-Syntactic Tagging of Text in “Baoule” Language Based on Hidden Markov Models (HMM)  [PDF]
Hyacinthe Konan, Bi Tra Gooré, Raymond Gbégbé, Olivier Asseu
Journal of Software Engineering and Applications (JSEA) , 2016, DOI: 10.4236/jsea.2016.910034
Abstract: The label text is a very important tool for the automatic processing of language. It is used in several applications such as morphological and syntactic text analysis, index-ing, retrieval, finished networks deterministic (in which all combinations of words that are accepted by the grammar are listed) or by statistical grammars (e.g., an n-gram in which the probabilities of sequences of n words in a specific order are given), etc. In this article, we developed a morphosyntactic labeling system language “Baoule” using hidden Markov models. This will allow us to build a tagged reference corpus and rep-resent major grammatical rules faced “Baoule” language in general. To estimate the parameters of this model, we used a training corpus manually labeled using a set of morpho-syntactic labels. We then proceed to an improvement of the system through the re-estimation procedure parameters of this model.
Linguistic – Stylistic Technique and the Effective Teaching and Learning of Poetry in Nigerian Senior Secondary Schools
GB Inyang
African Research Review , 2009,
Abstract: This study investigated the effect of linguistic-stylistic technique on the effective teaching and learning of poetry in Nigerian senior secondary school. The sample of the study comprised of 310 senior secondary two (SS II) students from six schools randomly selected from Itu Local Government Area of Akwa Ibom State, Nigerian A non-randomized pre-test post test control group design was used for the study. The reliability co efficient of poetry in English Achievement Test (PEAT) was 0.75 using Kuder- Richardson formula 21. The student’s t-test was used in the analysis of the data. The results showed that students taught with linguistic-stylistic technique achieved and retained better than students taught with traditional method in poetry. The results also showed an insignificant difference existing between the achievement of male and female students in poetry taught with linguistic-stylistic technique. It is recommended that linguistic-stylistic technique should be used in schools to teach various concepts in poetry.
Using Vocal and Silent Reading Approaches for the Enhancement of Effective Teaching and Learning of Reading Skills in English Language
GB Inyang
African Research Review , 2009,
Abstract: This study used the quasi experimental design to investigate the effectiveness of teaching reading skills in English Language through the use of vocal and silent reading approaches in Ini Local Government Area of Akwa Ibom State, Nigeria. A total of 182 junior secondary two (JS II) students made up the sample of this study. The instruments used for this study were Reading Instructional Package (RIP) and English Language Achievement Test (ELAT). From the findings, it was observed that vocal and silent reading approaches enhanced the academic performance of students in English Language. However, there was no significant difference in the academic performance of English Language students taught with vocal and silent reading approaches. The results also showed that gender is not a significant factor in the academic performance of students in English language when taught with vocal and silent reading approaches. It is therefore recommended that silent reading must precede vocal reading and both approaches should be adopted by the English Language teachers for the enhancement of reading skills of the students.
Effect of Tillage and Fertilizer Practices on Sorghum Production in Abergelle Area, Northern Ethiopia
GB Tesfahunegn
Momona Ethiopian Journal of Science , 2012,
Abstract: Sorghum (Sorghum bicolor L. Moench) production is mainly constrained by soil water and nutrient deficits in northern Ethiopia. The aim of this research was to evaluate the effects of tillage and fertilizer practices on productivity of two sorghum varieties in Abergelle area, northern Ethiopia. The experimental design was split-plot design. The main-plot treatments included five tillage practices. These were shilshalo (traditional ridge without ties) for broadcasted planting (SBP), tied-ridging at planting (TR0WAP), tied-ridging at four weeks after planting (TR4WAP), zero tillage (ZT), and shilshalo for row planting (SRP). Two fertilizer rates of nitrogen (N) and phosphorus (P), as0-0 N-P ha-1(without fertilizer, F1) and 32-10 kg N-P ha-1 (with fertilizer, F2) treatments, were used in the sub-plots. The local sorghum varieties i.e., Woitoziraand Chibal (Sorghum bicolor L. Moench) were tested for two years (2002-2003). The pooled and yearly-basis data analysis showed that the main and interaction treatment effects were significantly (P ≤ 0.05) influenced the yield and yield components of both varieties. This study also demonstrated sorghum yield increment by 7 to 48% due to the interaction effect of TR0WAP with F2 as compared to the interaction effects of the other tillage treatments with F2. However, the increment of yield and yield components due to the tied-ridging and fertilizer interaction effects were higher for Chibalas compared to Woitozira. The mean sorghum crop yield due to TR0WAP interaction with F2 for Chibal was 1.45 t ha-1 and that of Woitozirawas 1.31t ha-1. Thus, suitable time of tied-ridging integrated with proper rate of fertilizer should be adopted for effective increase of crop production in the semi-arid areas of northern Ethiopia such as the Abergelle area.
研制生态安全的固体火箭推进剂的可能途径(英)
Manilis,GB
含能材料 , 1995,
Abstract: 本文叙述了常规火箭推进剂燃烧时产生大量污染环境,危及人类生存的有害物质,如一氧化碳和含氯化合物等致癌物。为研制生态安全的推进剂,如果不首先考虑推进剂的能量高、化学安定性和燃烧特性俱佳的氧化剂,企图进一步解决其它问题就无意义。当然成本、工艺性和力学性能因素亦很重要。在探索研制配方时,可考虑选用硝酸铵、硝酸肼、二硝酰胺、硝仿肼等氧化剂取代NH4C1O4和HMX。为此,本文着重介绍了由七种对化剂组成的配方并进行了热力学计算,结果表明以NH4N(NO2)2:及N2H5C(NO2)3为基的配方的能量均高,而其燃烧室和喷管温度则分别低于以NH4C1O3和HMX为氧化剂的推进剂燃烧产生的高温。就上述氧化剂热分解参数而言,在20℃下,热分解0.1%所需时间,以NaC1O4的为最长,以NH4N(NO2)2的为最短。其顺序为:NaC1O4>NH4NO3>β-HMX>N2H5NO3>NH4C1O4>N2H5C(NO2)3>NH4N(NO2)2.文中对上述氧化剂的燃烧速率、压力指数和温度系数分别进行了实测和计算,除HMX外,所得两值均较一致;还介绍了燃烧..
Ecological Structure and Fruit Production of African Fan Palm (Borassus aethiopum) Populations  [PDF]
Christine Ouinsavi, Charlemagne Gbémavo, Nestor Sokpon
American Journal of Plant Sciences (AJPS) , 2011, DOI: 10.4236/ajps.2011.26088
Abstract: Ecological structure and fruit production of African fan palm stands in Benin were studied on the basis of surveys laid out in ten (10) populations located in three ecological zones. Dendrometric and fruit production parameters such as: diameter at breast height (dbh), total height (TH), number of fruit bunch per tree, number of fruits per tree, number of seeds per fruit, fruit length and width were measured on all African fan palm trees within thirteen (13) plots of 1,000 m². Diameter and height classes distribution of the palms in each ecological zone adjusted to Weibull distribution showed a bell shaped curve with left dissymmetry, characteristic of young stands (form coefficient between 1 and 3.6). African fan palm stem number was 156 trees/ha. Variation of dbh, TH, number of fruit bunch per tree were highly significant between populations and ecological zones (P < 0.05%). Trees from Sudanian zone were highly grown (mean dbh = 52.2 cm) while those of Sudano - Guinean transition zone were less (mean dbh = 32.73 cm) and dominated by female trees. African fan palm stands of Pahou is suitable for seed collection for in situ conservation of the species while those of Ouorghi and Akomiah could provide fruits for edible hypocotyls production.
Assessment of Organochlorine Pesticide Residues in Vegetable Samples from Some Agricultural Areas in Togo  [PDF]
Lankondjoa Kolani, Gbénonchi Mawussi, Komla Sanda
American Journal of Analytical Chemistry (AJAC) , 2016, DOI: 10.4236/ajac.2016.74031
Abstract: The study was conducted to monitor the concentration of pesticide residues in three staple vegetables (tomato, cabbage, lettuce) collected from 12 prefectures belonging to 4 agro-ecological regions of Togo. A total of 150 samples of ripe tomato, cabbage and lettuce were collected from the study areas and analyzed for 20 OCPs (organochlorine pesticides) residues, which can be grouped into DDTs, Drins, Heptachlors, Chlordanes and HCHs. The data revealed that 100% of the analyzed vegetable samples were contaminated by one or more pesticide residues; 83.32% and 100% were below the maximum residue limits (MRLs) set par European Union and FAO/WHO respectively whereas 16.68% were above the EU (MRLs) adopted values. Overall, cabbage contained the highest number of samples with pesticide residues above the MRLs followed by tomato, whilst none of lettuce samples contained pesticide residues above the MRLs. It is therefore proposed to perform continuous monitoring studies of pesticide residues in vegetables cultivated in Togo.
Dynamic Spectrum Access Protocol for the Digital Dividend  [PDF]
Raoul Zamblé, Raymond Gbégbé, Jean-Marie Kadjo, Olivier Asseu, Pac?me Brou
Circuits and Systems (CS) , 2016, DOI: 10.4236/cs.2016.713340
Abstract: It is not more and more, easy to satisfy the important and growing spectrum demands in the context of the static conventional policy spectrum allocation. Therefore, to find a suitable solution to this problem, we are to days observing the apparition of flexible dynamic spectrum allocation methods. These methods that ought to improve more significantly the spectrum use have gained much interest. In fact, the digital dividend due to the change-over from the analog television to the digital terrestrial television must be efficiently used. So the Dynamic Spectrum Access (DSA) can potentially play a key role in shaping the future digital dividend use. In the DSA, two kinds of users or networks coexist on different channels. The first one, known as the primary user, accesses to a channel with high priority; and the second one, known as secondary user has a low priority. This paper presents a dynamic spectrum access protocol based on an auction framework. Our protocol is an interesting tool that allows the networks to bid and obtain on the available spectrum, the rights to be primary and secondary users according their valuations and traffic needs. Based on certain offers, our protocol selects primary and secondary users for each idle channel in order to realize the maximum economic for the regulator or social benefits. We deal with the case in which the offers of the networks are independent one another even if they will share the same channels. We design an algorithm in accordance with our dynamic spectrum access protocol. The algorithm is used here to find an optimal solution to the access allocation problem, specifically to digital dividend. Finally, the results in the numeric section, regarding the three suggested scenarios, show that the proposed dynamic spectrum access protocol is viable. The algorithm is able to eliminate all non-compliant bidders for the available spectrum sharing. We notice that the revenue or social benefits of the regulator is maximized when we have on each channel, one primary user and the maximum number of secondary users.
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