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101.
Surface ultrastructures of gill filaments and secondary lamellae of Rita rita and Cirrhinus mrigala, inhabiting different ecological habitat, were investigated to unravel adaptive modifications. R. rita is a sluggish, bottom dwelling carnivorous catfish, which inhabits regions of river with accumulations of dirty water. It retains its viability for long time if taken out of water. C. mrigala is an active bottom dwelling Indian major carp, which lives in relatively clean water and dies shortly after taken out of water. In R. rita, gill septa between gill filaments are reduced. Microridges on epithelial cells covering gill filaments are often continuous and arranged concentrically. Secondary lamellae are extensive. The epithelium appears corrugated, show irregular elevations and shallow depressions, and microridges on epithelial cells appear fragmented. In C. mrigala, in contrast, the gill septa are extensive. Microridges on epithelial cells covering gill filaments are fragmented. Secondary lamellae are less extensive. The epithelium appears smooth and microridges on epithelial cells are relatively inconspicuous. These differences have been considered adaptive modification in relation to habit and ecological niches inhabited by two fish species. Presence of mucous goblet cells on gill filaments is discussed in relation to their functions including precipitation of the sediments and preventing clogging of gill filaments. Infrequent mucous goblet cells in the epithelium of secondary lamellae in two fish species are considered an adaptation, minimizing thickness of the epithelium to reduce barrier between blood and water for favoring gasses exchange with increased efficiency. 相似文献
102.
Purpurin (1,2,4‐trihydroxyanthraquinone) is the major colorant present in the roots of Indian madder (Rubia cordifolia). Its structure is similar to that of disperse dyes. To gain an understanding of the dyefibre interactions involved, kinetic and thermodynamic studies have been conducted with purpurin on nylon fibre. Dyeing corresponds to the Nernst isotherm as linear isotherms were obtained. The dye is found to be sensitive to pH and high temperature. The rate of dye uptake, diffusion coefficient, standard affinity, heat of dyeing and entropy have been calculated and discussed. 相似文献
103.
Nordamncanthal is an important constituent of the colouring matter extracted from Indian madder roots. Its dyeing properties have never been studied even though the structural characteristics closely resemble those of disperse dyes. In this study, nylon and polyester have been dyed with this colorant. Linear isotherms have been obtained, confirming that the mechanism is similar to that of disperse dyes. The dye has good affinity for both the fibres. Kinetic and thermodynamic parameters have been calculated. 相似文献
104.
Anil Kumar Lokesh Kumar Jangir Yogita Kumari Manoj Kumar Vinod Kumar Kamlendra Awasthi 《应用聚合物科学杂志》2016,133(41)
An attempt was taken to synthesize two types of polyaniline (PANI) with and without solvent followed by drying in air and vacuum oven conditions resulting different morphologies. The PANIs were prepared by chemical oxidative polymerization and studied with respect to their morphological features. Scanning electron microscopy, thermogravimetric analysis, X‐ray diffractometry, Fourier transform infrared spectroscopy, and ultraviolet–visible spectroscopy techniques were used for the characterization studies. The PANI synthesized with a solvent had a mixed morphology (fibrillar and granular), whereas PANI synthesized without a solvent had only a granular morphology. The direct‐current electrical conductivities of the samples were evaluated with an electrometer. We observed that the PANIs with mixed morphology (with solvent) were more electrically conducting than those with a single morphology (without solvent). On drying in vacuo, the conductivity of PANI decreased from 3.3 × 10?2 to 0.3 × 10?2 S/cm with solvent treatment, whereas it decreased from 0.1 × 10?2 to 0.3 × 10?3 S/cm without solvent treatment. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44091. 相似文献
105.
A polymer‐supported (PS) phase transfer catalyst, polyethylene‐g‐quaternary ammonium salt (PE‐g‐QN+), is prepared through a three‐step graft copolymerization of maleic anhydride (MAn) onto polyethylene (PE) by photochemical method using 1% benzophenone (Bz) as photosensitizer. Post grafted acid hydrolysis of polyethylene‐g‐maleic anhydride (PE‐g‐MAn) results in the preparation of PE‐g‐succinic acid which on further treatment with tetrabutylammonium bromide (TBAB) under basic conditions in tetrahydrofuran (THF) gives PE‐g‐QN+. Optimum conditions pertaining to maximum percentage of grafting have been evaluated as a function of concentration of maleic anhydride, amount of photosensitizer, and time of reaction. Maximum percentage of grafting (25%) was obtained using 3.57 mol of MAn and 0.5 mL of 1% Bz in 120 min. The PE and graft copolymers, PE‐g‐MAn, and PE‐g‐QN+ were characterized by FTIR Spectroscopy and thermogravimetric analysis (TGA). The ionic nature of quaternary ammonium salt, PE‐g‐QN+ has also been confirmed by conductance measurements. PE‐g‐QN+ reagent have been used successfully for polymerization, amidation, and esterification reactions. The products obtained were characterized by FTIR and H1NMR spectral methods. The reagent was reused for the further reactions and it was observed that the polymeric reagent polymerize, amidate, and esterificate the compounds successfully but with little lower product yield. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
106.
The effect of carbon black fillers viz. semireinforcing furnace (SRF), high abrasion furnace (HAF) and intermediate super abrasion furnace (ISAF) carbon blacks on the cure, swelling and mechanical properties of 70/30 EPDM/NBR blend have been investigated. The maximum torque values have been found to be increased with increase in filler loading. Filledsystems have been found to exhibit a reduced solvent uptake tendency compared to the unfilled sample. Blends loaded with ISAF exhibited the lowest toluene uptake among the carbon black filled systems due to the better filler reinforcement. A more uniform morphology has been observed for ISAF‐filled samples compared to the other filler loaded systems. The improvement in the mechanical properties has been observed to be the highest for ISAF‐filled samples followed by HAF and SRF filled systems. This has been attributed to the smaller particle size of ISAF black. The experimental results of mechanical testing have been compared with various theoretical models. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
107.
After burn or resection of one submandibular salivary gland the contralateral gland responded by an increase of proliferation. The maximal mitotic index was observed 48 hours after the resection and 72 hours after the burn. Burn of the salivary gland initiated a stable, but weak compensatory hypertrophy of the contralateral gland. Hypertrophy of the gland was accompanied by an increase in the size of the cells and the nuclei whose area enlarged by 10 and 17%, respectively. Resection of the salivary gland caused an increase in the weight of the intact contralateral gland only at the early periods of the experiment. By the 30th and the 45th day after the operation the weight of the intact contralateral gland failed to differ from control. The detected differences in the compensatory growth of the intact glands in two types of action on the contralateral salivary gland depended on the quantity of the tissue degeneration products and on the period of their stay in the organism. 相似文献
108.
109.
An approach to tackle protein-calorie malnutrition through domiciliary management is described. Children suffering from moderate and severe protein-calorie malnutrition were managed using a food supplement containing low cost locally available foodstuffs and nutrition education. An evaluation showed that the anthropometric improvement was closely associated with better concepts in nutrition and improved dietary practices following nutrition education. Parents of children suffering from kwashiorkor had better knowledge and practice compared with those of marasmus. 相似文献
110.
An analysis has been carried out to study the non-Darcy natural convention flow of Newtonian fluids on a vertical cone embedded in a saturated porous medium with power-law variation of the wall temperature/concentration or heat/mass flux and suction/injection with the streamwise distance x. Both non-similar and self-similar solutions have been obtained. The effects of non-Darcy parameter, ratio of the buoyancy forces due to mass and heat diffusion, variation of wall temperature/concentration or heat/mass flux and suction/injection on the Nusselt and Sherwood numbers have been studied. 相似文献