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Coating of Mineral Acids with Niobic Solid Acid for Preparing Furfural from Nut Shell of Camellia oleifera Abel  [PDF]
Lisong Hu, Menghao Du, Jingping Zhang
Open Journal of Forestry (OJF) , 2016, DOI: 10.4236/ojf.2016.65037
Abstract: Nut shell of Camellia oleifera Abel which has large scale of plantation in mountainous region of southern China is abundant renewable resource. The nut shell is suitable for preparation of furfural, as the content of which is as much as 16% (based the dried nut shell). In early time, mineral acids were employed as typically catalyst for preparing of furfural from the nut shells. These mineral acids could pollute water and corrode equipment. In this paper we used various mineral acids coating with niobic acid as catalysts to investigate reactions for preparation of furfural. Among these catalysts, the catalyst of sulfuric acid coating with niobic acid was found to be very effective, which had higher hammett acidity and better effect of hydrolysis of the nut shells; The catalysts of sulfuric acid coating with niobic acid was characterized, and the conditions of preparation of the catalyst were investigated. The optimum conditions were: sulfuric acid as coating acid, the concentration of sulfuric 1.1 mol/L, impregnation time 8 h, calcination time 8 h and calcination temperature 450°C. Then hydrolysis of the nut shells was explored, the optimum conditions were as follows: dose of catalyst 20%, ratio of solid to liquid 1:15, reaction temperature 100°C, reaction time 4 h; Under this condition, the yield of furfural was 8.7%.
Anti-Inflammatory and Analgesic Activities of a Novel Biflavonoid from Shells of Camellia oleifera  [PDF]
Yong Ye,Ya Guo,Yue-Ting Luo
International Journal of Molecular Sciences , 2012, DOI: 10.3390/ijms131012401
Abstract: Shells are by-products of oil production from Camellia oleifera which have not been harnessed effectively. The purpose of this research is to isolate flavonoid from shells of Camellia oleifera and evaluate its anti-inflammatory and analgesic effects. The flavonoid was identified as bimolecular kaempferol structure by UV, MS, 1H NMR and 13C NMR spectra, which is a new biflavonoid and first found in Camellia oleifera. It showed dose-dependent anti-inflammatory activity by carrageenin-induced paw oedema in rats and croton oil induced ear inflammation in mice, and analgesic activity by hot plate test and acetic acid induced writhing. The mechanism of anti-inflammation of biflavonoid is related to both bradykinin and prostaglandins synthesis inhibition. The biflavonoid showed both central and peripheral analgesic effects different from aspirin, inhibition of the synthesis or action of prostaglandins may contribute to analgesic effect of biflavonoid. The biflavonoid significantly decreased malonaldehyde (MDA) and increased superoxidase dismutase (SOD) and Glutathione peroxidase (GSH-Px) activity in serum ( p < 0.01), revealed strong free radical scavenging activity in vivo. It indicates the biflavonoid can control inflammation and pain by eliminating free radical so as to inhibit the mediators and decrease the prostaglandins. The biflavonoid can be used as a prospective medicine for inflammation and pain.
Evaluation of Dyestuff Removal by Shea Nut (Vitellaria paradoxa) shells
AU Itodo, HU Itodo, MK Gafar
Journal of Applied Sciences and Environmental Management , 2010,
Abstract: The removal of textile dyestuff from waste water was investigated in a batch sorption process using shea nut (Vitellaria paradoxa) shell activated carbon. The data were tested using the Rudishkevich – Dubinin and Temkin isotherm models. The result showed that removal efficiency increases with increase in contact time. This critical study which utilizes these more recent adsorption isotherms was found to present the mean free energy values (ED =1.036 – 1.406 kJmol-1) as a direct proportionality to the theoretical saturation capacities (qD = 2.032 – 4.169mgg-1). Sorption energy values proves to be higher for biosorbent, SS/A/15 (1.364 KJmol-1) ,which also gave the corresponding higher adsorption capacity (4.169 mgg-1) than the other three biosorbent in the series. A thermodynamic parameter (ΔG) was investigated to be more negative with sorbent – dye contact time, within the equilibration limit. The Close similarities of analytical results to those reported in reviewed literature, and the good degree of adsorption is an indication that using shea nut shells as a low cost biomass for generating activated carbon could be a feasible outlet in bioremediation. @JASEM J. Appl. Sci. Environ. Manage. December, 2010, Vol. 14 (4) 163 - 168
Peach-nut Shells-An Effective and Low Cost Adsorbent for the Removal of Endosulfan from Aqueous Solutions  [PDF]
G. Z. Memon,M. I. Bhanger,Mubeena Akhtar
Pakistan Journal of Analytical and Environmental Chemistry , 2009,
Abstract: In the present studies the adsorption efficiency of peach nut shells for the removal of endosulfan from aqueous solutions has been investigated. The adsorption of endosulfan has been studied as a function of contact time, concentration and temperature. Maximum adsorption (95 ± 1%) was achieved for 0.24 × 10 4 mol dm 3 of endosulfan solution, using 0.1 g of adsorbent in 20 ml of solution for 30 min agitation time at pH 6. The Freundlich and Langmuir isotherms fit the equilibrium data satisfactory and their constants, adsorption intensity 1/n (0.36), multilayer adsorption capacity Cm 6.5 ± 0.26 mmol g 1, and monolayer adsorption capacity Q 0.27 ± 0.03 mmol g 1, have been evaluated. Thermodynamics parameters namely change in enthalpy H, Gibbs free energy G and entropy S, were calculated. The negative values of G and positive value of H indicate that the adsorption process is spontaneous and endothermic in nature and positive value of entropy S confirms the possibility of the favorable adsorption. The developed adsorption method has been employed to surface water samples.
Astronomy at school: present situation and future perspectives  [PDF]
Maria Iglesias,Cynthia Quinteros,Alejandro Gangui
Physics , 2008,
Abstract: Both the basic educational contents for students and study programs for science teachers include several topics in physics and astronomy, from the simplest ones to others as advanced as nuclear fusion to explain stellar evolution and space-time geometry for an approach to modern cosmology. In all these subjects, and most often in the simplest ones, alternative conceptions emerge, as both groups reach science course with preconstructed and consistent models of the universe surrounding them. In this work we present a series of basic questionings that make us reflect on the present situation of the teaching-learning relationship in astronomy within the framework of formal education. We then briefly explain our project aiming at finding the real learning situation of both students and prospective primary-school teachers in astronomical topics and, from the expected results of it, we point towards the need to develop didactic tools that could contribute to improve formal education in astronomy issues.
Present situation and future of genetic profiling for prognosis and treatment
GN Hortobagyi
Breast Cancer Research , 2005, DOI: 10.1186/bcr1209
Abstract: The Human Genome Project was a major milestone in the history of medicine. Both the genetic information obtained and the technological advances that took place during this large multicenter effort have had enormous influence over all fields of medicine. For the field of prognostication and prediction in breast cancer, the major consequence was the development of technology that led to the simultaneous evaluation of gene expression for hundreds and, more recently, thousands of genes. In fact, recently launched gene arrays include the entire human genome. Thus, we have the opportunity to assess, in a small tumor sample, the expression profile of all known human genes. There are multiple technological platforms under evaluation for this purpose, and the results obtained with one cannot automatically be substituted for results obtained with another platform. Nevertheless, on the basis of several reports, it can be stated that gene expression profiling of human breast cancer provides valuable information in the following areas:1. Molecular classification of primary breast cancer2. Identification of multiple distinct prognostic subgroups3. Determination of expression level of several genes of interest (ER, PR, HER2, etc.)4. Identification of genetic networks5. Prediction of response to chemotherapyThe initial reports were based on small patient numbers that presented substantial statistical challenges for adequate estimation of end-points and to prevent frequent false-positive or false-negative results. More recent analyses have included several dozen and up to a few hundred patients. These reports provide greater statistical power and greater reliability. However, these reports still represent retrospective analyses of subsets of patients, and prospective validation is still sorely needed. Reports are beginning to appear comparing the performance of different platforms on the same tumor samples and considering the same end-points. The source of tumor material, the manner
Physic nut plants present high mycorrhizal dependency under conditions of low phosphate availability
Balota, Elcio Liborio;Machineski, Oswaldo;Viviane Truber, Priscila;Scherer, Alexandra;Souza, Fabio Suano de;
Brazilian Journal of Plant Physiology , 2011, DOI: 10.1590/S1677-04202011000100006
Abstract: the physic nut (jatropha curcas l.) is a perennial tree that occurs naturally in the tropical and subtropical regions of brazil. fruits of physic nut present an oil content of 28% on a dry weight basis. although the plant has adapted to diverse soil conditions such as low fertility, the correction of soil acidity and the addition of fertilizer are essential for highly productive plants. thus, the response of the physic nut to different soil phosphorus levels (p) and arbuscular mycorrhizal fungi (amf) inoculation must be characterized. hence, the objective of the present study was to evaluate the response of physic nut seedlings to arbuscular mycorrhizal fungi (amf) inoculation at different levels of soil p. experiment was carried out in a greenhouse encompassing amf treatments (inoculation with gigaspora margarita or glomus clarum, and the non inoculated controls), and phosphorus treatments (0, 25, 50, 100, 200 and 400 mg kg-1 added to soil). at low soil p levels, arbuscular mycorrhizal fungi inoculation had a significant positive effect on plant growth, shoot and root dry matter content, plant height, number of leaves, total leaf area, leaf area per leaf and the dickson quality index. the root:shoot ratio and the leaf area ratio were also affected by mycorrhizal inoculation and the level of p addition. physic nut plants exhibited high mycorrhizal dependency at soil p additions up to 50 mg kg-1.
Gasification of Cashew Nut Shell Using Gasifier Stovein Mozambique  [PDF]
Miguel M. Uamusse, Kenneth M. Persson, Alberto J. Tsamba
Journal of Power and Energy Engineering (JPEE) , 2014, DOI: 10.4236/jpee.2014.27002
Abstract:

Mozambique relies on wood biomass for meeting its household energy demand. This has been for long referred to as one of the main causes of the ongoing deforestation, mainly around the large cities and village. On the other hand, the country produces large quantities of agricultural crops residue which are still not being appropriately and integrally used as additional source of energy, especially for communities in the countryside where these residues are generated. Cashew nut shells (CNS) are among those residues. This kind of feedstock is said to be of high energy content. However, its utilization as energy source within the country is still poor.In Mozambique, 90% of the households depend on biomass for cooking. Biomass has already emerged in the renewable energy area as one of the promising candidates for the future energy source. Historically, biomass has been a major source of fuel from the existence of making rapid urbanization, but widespread use of fossil fuels in the industrialization has relegated it to a minor source of energy. The CNS Gasifier Stove developed has a thermal efficiency of 35.5% and an energy output of 2.19 kW. The corresponding values for LPG stove and Kerosene stove are 53.53% (0.69 kW) and 39.3% (0.6 kW), respectively. Though the use of CNS gasifier as a fuel is less efficient than the aforementioned one, with the rising oil prices and the search for alternatives to contemporary cooking fuels, it is still a viable alternative in this comparison.

Pseudorandomness of Camellia-Like Scheme
Wen-Ling Wu,
Wen-Ling
,Wu

计算机科学技术学报 , 2006,
Abstract: Luby and Rackoff idealized DES by replacing each round function with one large random function. In this paper, the author idealizes Camellia by replacing each S-box with one small random function, which is named Camellialike scheme. It is then proved that five-round Camellia-like scheme is pseudorandom and eight-round Camellia-like scheme is super-pseudorandom for adaptive adversaries. Further the paper considers more efficient construction of Camellia-like scheme, and discusses how to construct pseudorandom Camellia-like scheme from less random functions.
生物质能的开发与利用技术现状
Present Situation of Exploitation and Utilization Technology of Biomass
 [PDF]

薛庆涛, 朱颖颖, 李尊民
Sustainable Energy (SE) , 2016, DOI: 10.12677/SE.2016.63007
Abstract:
通过对生物质开发利用技术的研究,结合现有的生物质转化方法,介绍了生物质在固化、液化、气化及生化转化方面的技术特点和研究方法;简述了费托合成技术的不足与改进措施;指出在现有技术下生物质能的发展方向;得出大力发展生物质能技术对能源利用和环境保护具有积极作用。
By researching on development and utilization technology of biomass and combining existing bio- mass converting methods, this paper introduced biomass’s technical characteristics and research methods in biomass-curing, biomass liquefaction, biomass gasification and biochemical conversion of biomass. Moreover, this paper illustrated the disadvantages and improvement measures of Fischer-Tropsch Synthesis, arriving at the biomass energy’s developing direction in current technology. This paper eventually pointed out that it was beneficial to energy using and environmental protection to develop biomass energy technology.
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