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1.
Highly aligned ultrafine fibers of Poly (amide-co-imide) PAI (torlon)/Poly (trimellitic anhydride chloride-co-4, 4′-methylene dianiline) (PTACM) blends have been prepared by using mechano-electrospinning. Employing a mixed solvent system of DMSO and THF alongwith water coagulation bath as a medium, continuous fibers with improved mechanical properties have been obtained. The continuity of the fibers is strongly dependent on the solvent mixing ratio of DMSO and THF (6:4). Continuous fibers with the most uniform diameter are obtained when a 30 % of PAI and PTACM (1:1) resins by weight is used in the blending solution. The aligned fibers are further coated with silver nanoparticles using a one-step process by passing the electrospunned fibers through PEG solution and a silver precursor solution followed by reduction in a continuous process. The advantage of our method lies in a uniform silver coating on a single fiber that can be coated continuously on a larger length scale (~Km). The mechanical properties of these fibers are dramatically improved after their alignment. Better electrical conductivity is obtained for these fibers after they are coated with silver nanoparticles. The highly aligned silver decorated fibers utilizes a novel electroless continuous process using Polyethylene glycol (PEG), which shows good binding properties and can be used for various bio and electronic applications.  相似文献   
2.
Summary Interspecific hybrids have been obtained in an otherwise incompatible cross betweenBrassica juncea × Brassica hirta through the in vitro culture of hybrid ovules and ovaries. The best response was observed from ovules and ovaries cultured 10–15 and 5–7 days after pollination respectively on a basal medium supplemented with indoleacetic acid, kinetin and casein hydrolysate. In some cases the basal cut end of the ovaries proliferated to form callus and shoots. The in vitro-derived hybrid seeds varied in their colour, size and shape, and the F1 plants in the field showed a large diversity in their morphological traits. The hybrids were sterile, and had an intermediate number of chromosomes (2n=30).  相似文献   
3.
Colorimetric determination of caffeic acid in plant materials   总被引:1,自引:0,他引:1  
A new colorimetric method is described for determining caffeic acid content in plant materials. Caffeic acid is separated by thin layer chromatography from the alcoholic extract, and color is developed using 0.5% aqueous thiosemicarbazide solution under alkaline conditions. The absorbance is read at 475 nm. Lambert-Beer's law is obeyed in the concentration range 0.37-17.5 micrograms caffeic acid/mL. The method is reproducible and has been applied to the estimation of caffeic acid in carrot roots.  相似文献   
4.
Callus tissue cultures have been established from the excised segments of the inflorescence, flower stalks, denuded flower, bract, perianth and leaf segments of 2 cultivars of Gladiolus grandiflorus. Of all the explants and the media tested, the best callus was obtained from the segments of the flower stalks, cultured on a basal medium supplemented with naphthalene acetic acid and kinetin. The callus mostly underwent rhizogenesis, and occasionally differentiated shoots. Complete plants were regenerated from the in vitro cultured cormels, cormel tips and the axillary buds, and 6 plants were formed from the segments of 1 cormel, whereas in nature only 1 plant is obtained per cormel. Cultured young anthers callused and developed leaf-like petaloid structures, and occasionally showed multicellular pollen.  相似文献   
5.
Twenty three cultivars of carrot (Daucus carota L.) roots consisting of fifteen local and eight exotic cultivars were analysed for various chemical constituents including dry matter, total soluble solids (TSS), -carotene, total and reducing sugars, phenolics, phosphorus, zinc, manganese, copper, iron, sodium potassium and ash. In addition other characteristics such as days to maturity, root weight and length, flesh thickness, core diameter, number of forked and cracked roots per plot have been studied. Yellow carrots were found to have maximum root length, water soluble carbohydrates and minimum -carotene content. The exotic cultivars were found to have higher TSS content than the local cultivars, while the latter cultivars had higher mineral contents than the former. However, on the average, dry matter content, total water soluble sugars, reducing and non-reducing sugars were found to be greater in exotic cultivars than in local ones, but -carotene, phenols and phosphorus contents were greater in local cultivars. A significant positive correlation between -carotene content, ash percentage and days to maturity was observed. A wide variation in chemical constituents and plant characteristics was observed indicating a high genetic variability in the material under study.  相似文献   
6.
Composite flours prepared from wheat, greengram, bengalgram and blackgram flours were studied for the preparation of biscuits. Protein content of biscuits increased as the level of the pulse flours increased. Wheat flour containing bengalgram and blackgram flours adversely affected the top grain, texture and colour of biscuits. Biscuits made with higher levels of bengalgram (more than 15%) were tough and difficult to break and required higher compression force. Addition of greengram flour did not significantly affect top grain, texture and colour of biscuits. The biscuits made from 15% greengram supplemented wheat flour scored the highest for flavour characteristics. Thickness, diameter and spread ratio of biscuits containing different levels of pulse flours were significantly different from control sample. Sensory evaluation scores showed that acceptable biscuits can be prepared from wheat flour supplemented with these pulse flours at a level of 15 percent.  相似文献   
7.
The effect of different levels of nitrogen N0(0kg/ha), N1(30 kg/ha), N2 (60 kg/ha), and N3 (90 kg/ha) and farmyard manure F0 (0 tonnes/ha), F1 (10 tonnes/ha), and F2 (20 tonnes/ha) on the yield and nutrient composition of spinach and its uptake was investigated on a sandy loam soil. Yield; phosphorus, iron, manganese, zinc, and copper uptakes; and ascorbic acid content increased with the application of both the inorganic nitrogen fertilizer and the farmyard manure, with a maximum at the N3F2 level, i.e. at 90 kg N/ha with 20 tonnes FYM/ha. However, the contents of protein, -carotene, and reducing sugars were maximum at the highest dose of nitrogen without the application of farmyard manure.  相似文献   
8.
Two varieties of potatoes viz. Kufri Chandramukhi and Kufri Sindhuri were treated with Isopropyl-N(3-chlorophenyl)carbamate at two different concentrations viz. 4000 and 5000 ppm. The treated potatoes were stored for a period of four months under different storage conditions i.e. room temperature, cold and evaporative cooling chamber storage and analysed for polyphenol oxidase activity, total nitrogen content and quality of dried slices produced from these at different stages of storage. Higher nitrogen content was observed in CIPC treated potatoes as compared to control. Polyphenol oxidase activity decreased more in Kufri Chandramukhi than in Kufri Sindhuri in CIPC treated as well as in control experiments. The changes in nitrogen content and polyphenol oxidase activity were more pronounced in evaporating cooling chamber and in room storage than in the cold storage. The quality of potato slices prepared from both varieties confirmed the superiority of Kufri Chandramukhi over Kufri Sindhuri for processing purposes.  相似文献   
9.
Summary The embryos of a cultivated tetraploid peanut (Arachis hypogaea), a wild diploid species (A. villosa), and their hybrid embryos, which generally abort in nature, were cultured in vitro and the plants have been successfully transferred to the soil. The hybrids showed triploid chromosome number (3x=30). The significance of wide hybridization in peanut-improvement programs is discussed.  相似文献   
10.
The nutritive quality of carrots, obtained from different herbicide-treated plots and under different levels of nitrogen application ranging from zero to 80kg nitrogen/ha, was compared. There were significant differences in carotene content, T.S.S. (total soluble solids) and organolptic characteristics under the influence of different treatments. The maximum carotene content, T.S.S. and organoleptic characteristics were observed with the application of 80 kg. nitrogen/ha and fluchloralin herbicide at 0.90 and 1.20 kg/ha.  相似文献   
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