Juglans Regia L. (juglans + regia_l)

Distribution by Scientific Domains


Selected Abstracts


Combustion properties of laminated veneer lumbers bonded with PVAc, PF adhesives and impregnated with some fire retardants

FIRE AND MATERIALS, Issue 3 2010
eref Kurt
Abstract In this study, the effects of impregnation materials di-ammonium phosphate, aluminium sulphate, potassium carbonate, calcium chloride, zinc chloride on combustion properties of 3 ply laminated veneer lumbers (LVL) produced from Walnut (Juglans regia L.) using phenol,formaldehyde (PF), poly (vinyl acetate) have been investigated. The pressure-vacuum method was used for impregnation process. Combustion test was performed according to the procedure of ASTM-E 69 standards. During the test, mass reduction, temperature and released gas (CO, NOX, SO2, O2) were determined every 30,s. As a result, zinc chloride was found to be the most successful fire-retardant chemical in LVL at PF adhesive. Since it diminishes combustion, the fire retardant of LVL produced from walnut using PF adhesive can be advised. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Seasonal Variation and Correlation with Environmental Factors of Photosynthesis and Water Use Efficiency of Juglans regia and Ziziphus jujuba

JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 2 2008
Hai-Bo Yang
Abstract Both the photosynthetic light curves and CO2 curves of Juglans regia L. and Ziziphus jujuba Mill. var. spinosa in three seasons were measured using a LI-6400 portable photosynthesis system. The maximal net photosynthetic rate (Amax), apparent quantum efficiency(,), maximal carboxylation rate (Vcmax) and water use efficiency (WUE) of the two species were calculated based on the curves. The results showed that Amax of J. regia reached its maximum at the late-season, while the highest values of Amax of Z. jujuba occurred at the mid-season. The Amax of J. regia was more affected by relative humidity (RH) of the atmosphere, while that of Z. jujuba was more affected by the air temperature. Light saturation point (LSP) and Light compensation point (LCP) of J. regia had a higher correlation with RH of the atmosphere, those of Z. jujuba, however, had a higher correlation with air temperature. Vcmax of both J. regia and Z. jujuba had negative correlation with RH of the atmosphere. WUE of J. regia would decrease with the rise of the air temperature while that of Z. jujuba increased. Thus it could be seen that RH, temperature and soil moisture had main effect on photosynthesis and WUE of J. regia and Z. jujuba. Incorporating data on the physiological differences among tree species into forest carbon models will greatly improve our ability to predict alterations to the forest carbon budgets under various environmental scenarios such as global climate change, or with differing species composition. [source]


Walnut Staminate Flowers Can Be Explored as a Supplementary Plant Oil Source

JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 4 2006
Husen Jia
Abstract Fossil fuel is currently the major energy source driving global socio-economy, but its stock is being heavily depleted due to increasing anthropogenic activities worldwide. There are also concerns regarding the burning of fossil fuels, which contributes to global climate warming and air pollution. As such, the development of biodiesel as a non-toxic, biodegradable, and renewable alternative energy source using oil crops such as soybean and rapeseed has quickly emerged in the West countries. However, the production of oil crops in China is far from sufficient to meet the demands of the country's population of 1.3 billion, and increasing oil crop production is inhibited by a severe shortage of agricultural land, which currently averages 0.2 acre per person and, as such, is less than half the world average. The current national policy in China regarding land use is more towards revering cultivated lands in ravins and hills to forestry, which presents an ideal opportunity to further develop plantations of walnut (Juglans regia L.) trees, a plant that is tolerant to drought and infertile soils and has a high oil content. Study in this paper shows that one ament of walnut staminate flowers produces about 0.168 g dry pollen, and the dry pollen contained 49.67% oil. Based on this discovery, oil yield obtained from staminate flowers is estimated to reach 6.95% of that from walnut nuts. Thus walnut staminate flower is suggested to explore as supplementary plant oil source, and has a great opportunity to utilize as a biodiesel feedstock. (Managing editor: Wei Wang) [source]


Walnut (Juglans regia L.): genetic resources, chemistry, by-products

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2010
Marcela L Martínez
Abstract Walnut (Juglans regia L.) is the most widespread tree nut in the world. There is a great diversity of genotypes differing in forestry, productivity, physical and chemical nut traits. Some of them have been evaluated as promising and may serve as germplasm sources for breeding. The nutritional importance of the nut is related to the seed (kernel). It is a nutrient-dense food mainly owing to its oil content (up to 740 g kg,1 in some commercial varieties), which can be extracted easily by screw pressing and consumed without refining. Walnut oil composition is dominated largely by unsaturated fatty acids (mainly linoleic together with lesser amounts of oleic and linolenic acids). Minor components of walnut oil include tocopherols, phospholipids, sphingolipids, sterols, hydrocarbons and volatile compounds. Phenolic compounds, present at high levels in the seed coat but poorly extracted with the oil, have been extensively characterised and found to possess strong antioxidant properties. The oil extraction residue is rich in proteins (unusually high in arginine, glutamic and aspartic acids) and has been employed in the formulation of various functional food products. This review describes current scientific knowledge concerning walnut genetic resources and composition as well as by-product obtainment and characteristics. Copyright © 2010 Society of Chemical Industry [source]


Determination of a novel diarylheptanoid (Juglanin B) from green walnut husks (Juglans regia L.) in rat plasma by high-performance liquid chromatography

BIOMEDICAL CHROMATOGRAPHY, Issue 3 2010
Xin-Yi Huang
Abstract A simple and reliable analytical method based on high-performance liquid chromatography (HPLC) coupled with a diode array detector (DAD) was developed for the determination of a novel diarylheptanoid (Juglanin B) from green walnut husks (Juglans regia L.) in rat plasma using rhoiptelol as an internal standard. Chromatographic separation was carried out on a Sinochrom ODS-AP C18 column (250 × 4.6 ,m i.d., 5 mm) with acetonitrile,10 mM postassium dihydrogen phosphate (pH = 3; 55:45, v/v) as mobile phase, and the detection wavelength was set at 214 nm. The plasma samples were prepared using methanol as protein precipitator. The extraction recovery of Juglanin B ranged from 70.26 to 78.59%, and the calibration curve had a good linearity in the range 0.08,50 ,g/mL (r2 = 0.9932). The RSDs of intra- and inter-day precision ranged from 1.19 to 4.92% and 4.35 to 4.54%, respectively. The HPLC-DAD method described is a simple, rapid and reliable method for the determination of Juglanin B level and for use in studies involving pharmacokinetics. Copyright © 2009 John Wiley & Sons, Ltd. [source]