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Flexural Performance of I-Joist Fabricated with Glue-Laminated Bamboo and Gmelina arborea Plywood  [PDF]
Viviana Paniagua, Róger Moya
Open Journal of Civil Engineering (OJCE) , 2014, DOI: 10.4236/ojce.2014.43018

The search for efficient and versatile structural elements, leads to the fabrication of I-joists (6.5 cm × 18.5 cm × 600 cm (width × depth × length) with glue-laminated bamboo (Guada angustifolia) in the flanges and Gmelina arborea 12-mm structural plywood in the web. The results showed a modulus of rupture (MOR) of 39.45 MPa and an effective modulus of elasticity (MOE) of 17.05 GPa. Shearing in the glue line was 5.95 MPa and the lamination strength was 6.45 MPa. Structural design values averaged 9.43 MPa for bending and 4.72 MPa in shear according to Costa Rican structural standards. Both resistance value (flexure and shear) were considered satisfactory for structural proposes and I-joists fabricated with bamboo and G. arborea plywood are comparable with the Andean classification group “C” structural grade. The use of this I-joist was also shown in roofing and flooring systems. This beam can be used in allowable spans from 2 to 4 m in span for flooring systems and from 5 to 7 m for roofing applications.

Kaswala Rohit,Patel Vaibhav,Chakraborty Manodeep,Kamath Jagadish V
International Research Journal of Pharmacy , 2012,
Abstract: Gmelina arborea Roxb (Family- Verbenaceae) commonly known as ‘Gamhar’ is a beautiful fast growing deciduous tree throughout in Indiaand one of the herbs mentioned in all ancient scriptures of Ayurveda.It is known to have been used in traditional Indian medicine having important source of chemicals of immense medicinal and pharmaceutical importance such as flavonoids, alkaloids, arboreol, isoarboreol, methyl arboreol, gummadiol, gmelanone ,gmelinol, n-hexacosnol, n-octanol, β-sitosterol and luteolin. Various studies indicated that it possesses antioxidants, diuretic, anthelmintic activity, cardioprotective, antidiabetic, immunomodulatory, antipyretic and analgesic, antimicrobial and in the treatment of jaundice, headache, useful in hallucination, piles, fever and ‘Tridosha’as a folk remedies. The review focuses on the detailed phytochemical composition and medicinal uses along with pharmacological properties of different parts of G.arborea.
Effect of Incision on Preservative Absorption Capacity of Gmelina arborea Wood  [PDF]
J.M. Owoyemi,J.O. Kayode
Biotechnology , 2008,
Abstract: The effect of incision on preservative absorption capacity of Gmelina arborea wood was investigated using Copper Chrome Arsenate (CCA), creosote oil and Cashew Nut Shell Liquid (CNSL) preservatives. The result revealed that incising improved the uptake of the preservatives by the wood with a percentage absorption of 9.44 ± 3.28 compared with unincised; 7.83 ± 2.96. Using 555 incisions m-2 to an incision depth of 5 mm statistically showed significant difference between incised and unincised treatments. Also, there was significant difference between CCA and the other two preservatives in the absorption capacity of Gmelina arborea wood. The highest percentage absorption 13.60 ± 1.91 was recorded for CCA, followed by creosote oil 7.8 ± 0.66, while CNSL has the least absorption 6.92 ± 0.80.
Physical and mechanical properties of plywood panels manufactures with tropical plantation species for structural use  [PDF]
Carolina Tenorio,Roger Moya,Diego Camacho
CERNE , 2012,
Abstract: Concrete, steel and plastics are the materials used for construction in Costa Rica. Meanwhile, wood from plantation are being introduced in the market. The present study aims to characterize and measured some physical and mechanical properties of plywood panels manufactured with veneers of Gmelina arborea, Tectona grandis and Acacia mangium coming from forest plantations for structural use. It was produced three plywood boards of each species and general characterization of them was done, and physical and mechanical properties were determined. The results shown that panels manufactured with T. grandis wood presented physical and mechanical properties higher than G. arborea and A. mangium. In accordance with standards of Voluntary Products Standart PS 1-95 and PS 1-09 of the United States, structural plywood of G. arborea can be grouped in grade 3, and plywood manufactured with T. grandis and A. mangium wood in grade 2. All species can be used in the manufacture of structural elements.
Physiological response of gmelina (Gmelina arborea Roxb.) to hydric conditions of the colombian Caribbean  [cached]
Rojas Andrea,Melgarejo Luz Marina,Rodríguez Miguel,Moreno Leonardo
Agronomía Colombiana , 2012,
Abstract: Gmelina is an important forest species because of its adaptability to different tropical environments, rapid growth and high quality wood for many uses. Although the species thrives in lowlands, both wet and dry, water availability is the main limiting factor for production in the latter. The transpiration rate, stomatal resistance, water potential and chlorophyll and carotenoid pigments content were monitored for three climatic seasons (rainy, transitional and dry) and three ages (seedling (2-10 months), juvenile (10-16 months) and adult (48-60 months)), in order to observe the physiological response of gmelina to conditions in northern Colombia. Transpiration rates decreased with the age of the trees and the critical value of leaf water potential, that generates stomatal closure, was observed below -2.6 MPa. The dry season resulted in increased carotenoid content, in contrast to the content of chlorophyll A, B and total.
Rohit Sahu,Goli Divakar,Kalyani Divakar
Journal of Advanced Pharmaceutical Technology & Research , 2010,
Abstract: Gmelina arborea Roxb (family Verbenaceae) commonly known as ‘Gambhari’tree, the various parts of the plants are widely used in diarrhoea, anti-pyretic, thirst,anemia, leprosy, ulcers, consumption, strangury, vaginal discharges. We tested thegenotoxic potential of G. arborea in bone marrow cells obtained from Swiss albino miceusing micronuclei formation as the toxicological endpoints. Aqueous extract of G.arborea (AEGA) was tested at the dose of 286 & 667 mg/kg body weight (b. w.).Cyclophosphamide (CPZ) 25 mg/kg b. w. was used as positive control in micronucleustest. The AEGA significantly increased the % micronucleated polychrometics at doses of286mg/kg and 667mg/kg, after 24, 48 72h time interval. And also decreased thePCE/NCE ratio after 24, 48 and 72 h as compared to solvent control group. In this study,we investigated the effect of G. arborea on mammalian bone marrow cells usingmicronuclei formation to assess the genotoxicity of the herb.
Effect of Arbuscular Mycorrhizal Fungi on Growth and Antioxidant Activity in Gmelina arborea Roxb. under Salt Stress Condition  [cached]
Mayura Prakash DUDHANE,Mahesh Yashwant BORDE,Paramjit Kaur JITE
Notulae Scientia Biologicae , 2011,
Abstract: Gmelina arborea Roxb. is medicinally and economically important tree species were selected for study. An experiment was conducted to determine the influence of arbuscular mycorrhizal (AM) fungus Glomus fasciculatum on salt stress tolerance of tree species Gmelina arborea. Mycorrhizal and nonmycorrhizal seedlings were treated with 100 mM and 200 mM concentration of NaCl. G. fasciculatum treated plant showed increase in fresh and dry weight, greater percentage of mycorrhizal colonization, higher accumulation of proline and chlorophyll content with increasing levels of salinity. G. fasciculatum colonization significantly increased tolerance of salinity, acid phosphatases, and Proline content and also antioxidant enzymes like peroxidase, catalase and superoxide dismutase at all levels of salinity treatments of Gmelina plants in comparison with non-mycorrhizal salinity treated plants. These results demonstrate that AM fungus (G. fasciculatum) is very effective in strengthening the tolerance of Gmelina arborea grown in arid and semi arid areas.
Potent in vitro Cytotoxic Effect of Gmelina arborea Roxb. (Verbenaceae) on Three Human Cancer Cell lines.
David Punitha,Angamuthu Thandavamoorthy,Karuppanan Arumugasamy,Uthaman Danya
International Journal of Pharma Sciences and Research , 2012,
Abstract: Cancer is one of the most common devastating disease affecting millions of people per year. It has been estimated as the second leading cause of death in humans. In the present study, the cytotoxicity of ethanolic leaf extracts of Gmelina arborea (Verbenaceae) was tested against Colon cancer (COLO 201), Gastric cancer (HT- 29) and Human oesophagel cancer (TE-2) cell lines using the thiazolyl blue test (MTT) assay. Ethanolic leaf extracts of G. arborea was exhibited a prominent inhibitory effect against COLO 201 (IC 50- 20±0.15 mg/ml), HT-29 (IC 50-12±0.32 mg/ml) and TE-2 (IC 50- 16±0.05mg/ml) under in vitro condition. From the results it could be found that G. arborea ethanolic leaf extract has potent in vitro cytotoxic activity.
M Rashidi,SS Deokule
International Journal of Research in Ayurveda and Pharmacy , 2012,
Abstract: The roots of plant Gmelina arborea Linn. were selected for the present investigation. The roots were stored at different relative humidities 30, 50, 75, 96 and 100% RH for 90 days. Total 15 fungal species were isolated from these roots. Quantitative estimation of phenols, proteins, alkaloids, glycosides and sugars in relation to fungi were done. Maximum percentage incidence of storage fungi as well as deterioration of chemical constituents in the roots was showed at above 75% RH.
Effects of Age and Sampling Position on Wood Property Variations in Nigerian Grown Gmelina Arborea
OY Ogunsanwo, AS Akinlade
Journal of Agriculture and Social Research (JASR) , 2011,
Abstract: Wood properties of plantation grown (Gmelina arborea Roxb.) were evaluated in this study. Eighteen trees from 3 age classes namely: 18, 28 and 36 years were sampled at the butt, 50% merchantable length ML and 90% ML, and were radially partitioned into inner wood, middle wood and outer wood, on the basis of distance from pith. Result obtained was analyzed using ANOVA at 5%level. Mean SG were 0.33 for age 18, 0.41 for 28 and 0.46 for the 36 year old Gmelina. While SG varied inconsistently in 18 year old Gmelina, it decreased significantly from butt to 90% ML in 28 and 36 year old trees. MOR ,MOE and MCS// decreased generally from base to top for all age classes except in 28 year old, where variation in MOE was inconsistent. All properties studied increased from inner wood to outer wood. Axial uniformity in strength properties ranged between 0.50 and 0.64, 0.65 and 0.73, and from 0.49 to 0.82 in MOR, MOE and MCS respectively. Radial uniformity index also ranged between 0.69 and 0.78 in MOR, 0.78 and 0.85 in MOE and between 0.76 and 0.80 in MCS. For all the properties studied, wood uniformity was best in 36 year Gmelina along the radial plane, while 18 year Gmelina had the best uniformity index along the axial plane. Effect of age was highly significant on strength properties and its variation patterns. In particular, there was about 44.8% increase in strength properties from 18 to 28 years and 19.1% increase from 28 to36 years. Woods of Gmelina arborea varied significantly along and across the bole, and should be treated as such in their conversion and utilization strategies.
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