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101.
102.
Microbial degradation of the oil soluble corrosion inhibitor (OSCI) Baker NC 351 contributed to a decrease in inhibitor efficiency. Corrosion inhibition efficiency was studied by the rotating cage and flow loop methods. The nature of the biodegradation of the corrosion inhibitor was also analysed using Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry. The influence of bacterial activity on the degradation of the corrosion inhibitor and its influence on corrosion of API 5LX were evaluated using a weight loss technique and impedance studies. Serratia marcescens ACE2 and Bacillus cereus ACE4 can degrade aromatic and aliphatic hydrocarbons present in the corrosion inhibitor. The present study also discusses the demerits of the oil soluble corrosion inhibitors used in petroleum product pipeline.  相似文献   
103.
Surface plasmon-coupled emission (SPCE) has led to significant advancements in analytical techniques on account of its unique characteristics that include highly polarized photon-sorting ability. In this study, we report the use of a low-cost activated carbon as a plasmonic spacer in the SPCE substrate for achieving 30-fold enhancement in fluorescence emission. We extend the use of this spacer in the presence of Rhodamine B Base, a lactone dye as the sensing material for smartphone-based ethanol detection on the SPCE platform. Ethanol detection from 1 to 6% concentration highlights the potential use of this technique in monitoring fermentation processes.  相似文献   
104.
Tissue-specific age-dependent changes were observed in Na+K+-, Ca2+-, and Mg2+-ATPase activities in tropical tasar silkworm, Antheraea mylitta Drury. Maximum enzyme activity was recorded in all the tissues on day 12 (before spinning) in control group of animals. In testis, Na+K+-, Ca2+-, and Mg2+-ATPase activities gradually increased from day 2 to day 12 during fifth larval age and level was maintained up to adult eclosion while, in ovary, a marked decline was noted up to day of adult emergence. Further, a significant and sharp rise was found in ATPase activity in silk gland tissue up to day 12 and afterwards a drastic fall was noted on day 15 (end of spinning) during fifth larval age.Administration of T4 to fifth stage larvae (1 hr old) at doses 0.5–2.0 μg/g significantly elevated the Na+K+-, Ca2+-, and Mg2+-ATPase activities in larval and pupal gonads in a dose-dependent fashion. But, in moths, the enhancement was very much confined to Na+K+- and Ca2+-ATPase in testes and only Ca2+-ATPase in ovaries. Again, in silk glands thyroxine (0.5–2.0 μg/g) caused a significant rise in the all ion-dependent ATPase activities only during the fifth larval stage. Interestingly, higher doses of T4 (4.0 μg/g) caused a significant reduction in Na+K+-, Ca2+- and Mg2+-ATPase in all the tissues almost all the days studied so far. However, lower doses of T4 (0.1 and 0.25 μg/g) remained ineffective in altering the different ion-specific ATPase activities. This study suggests, that mammalian thyroxine has a metabolic influence showing biphasic nature of action in tasar silkworm ATPase system.  相似文献   
105.
The high molecular weight (680 KDa) glycolipoprotein from the haemolymph of male larvae of Antheraea mylitta Drury (Lepidoptera: Saturniidae) was identified as lipophorin by gradient KBr ultracentrifugation and SDS-PAGE. This lipophorin is composed of two subunits: apolipoprotein 1 (234 KDa) and apoprotein II (80 KDa). The density of the native molecule is 1.1941 g/ml. By weight, it contains 53.7% protein, 3.7% carbohydrate, and 42.6% lipid. Neutral lipids and phospholipids are 66.2 and 33.8% of the total lipids, respectively. Mannose and N-acetylglucosamine are the only sugars detected by gas liquid chromatography. The amino acid composition of both the native molecule and its two subunits was determined, and yielded similar amino acid compositions. © 1996 Wiley-Liss, Inc.  相似文献   
106.
High-bandwidth measurements of the ion current through hafnium oxide and silicon nitride nanopores allow the analysis of sub-30 kD protein molecules with unprecedented time resolution and detection efficiency. Measured capture rates suggest that at moderate transmembrane bias values, a substantial fraction of protein translocation events are detected. Our dwell-time resolution of 2.5 μs enables translocation time distributions to be fit to a first-passage time distribution derived from a 1D diffusion-drift model. The fits yield drift velocities that scale linearly with voltage, consistent with an electrophoretic process. Further, protein diffusion constants (D) are lower than the bulk diffusion constants (D0) by a factor of ∼50, and are voltage-independent in the regime tested. We reason that deviations of D from D0 are a result of confinement-driven pore/protein interactions, previously observed in porous systems. A straightforward Kramers model for this inhibited diffusion points to 9- to 12-kJ/mol interactions of the proteins with the nanopore. Reduction of μ and D are found to be material-dependent. Comparison of current-blockage levels of each protein yields volumetric information for the two proteins that is in good agreement with dynamic light scattering measurements. Finally, detection of a protein-protein complex is achieved.  相似文献   
107.
Male urinary lipocalin family proteins, practically odorant-binding proteins but also could be pheromones by themselves, in rodents act as a shuttle for chemosignal communication and facilitate delivery of the signals for access to congeners. However, presence of this protein in urine of female rodents has not yet been reported. Therefore, the present investigation was carried out to find if lipocalin family protein is present in the urine of female house rat and, if so, to find whether its expression differs between the phases in the estrous cycle. The rat urinary protein was separated in single dimensional gel electrophoresis. A 14.5 kDa lipocalin protein appeared in the urine prominently during the estrus and metestrus phases compared to proestrus and diestrus phases. The expression of this protein in the urine was very low in ovariectomized rats. MALDI-TOF/MS analysis affirmed the 14.5 kDa protein as a lipocalin family protein. Analysis adopting bio-informatics tools further proved the protein as a lipocalin family member. Thus, this study for the first time demonstrated the presence of a lipocalin family protein in the urine of a female rodent and it was highly expressed during estrus phase. This lipocalin protein in female rat urine may facilitate a chemosignal function independently of a pheromone or in association with a specific pheromone.  相似文献   
108.
We analyzed mycorrhizal types and dark septate endophyte (DSE) fungal associations in a shola vegetation of Western Ghats region, southern India. Plants belonging to 29 species of 19 families were assessed for mycorrhizal type and DSE fungal association. Five mycorrhizal classes were classified based on morphological traits: arbuscular, ecto-, ectendo-, ericoid-, and orchid mycorrhizas. Arbuscular mycorrhizal (AM) association was the most predominant mycorrhizal type, occurring in 16 plant species, followed by orchid (3 species), ericoid- (2 species), and ecto- and ectendomycorrhizas (1 species each). Mycorrhizal association is reported for the first time in 19 plant species. DSE fungal association was found in six plant species. Arum- and Paris-type AM morphology was found, respectively, in 10 and 5 plant species, with intermediate type recorded in one species. In this study, some new records on the morphological types of AM in some plant families were obtained. Further occurrence of ectendomycorrhizas in Pinus oocarpa and dark septate fungal association in Eleaocarpus munronii, Symplocos cochinchiensis, Daphniphyllum neilgherrense, Euodia roxburghiana, Syzygium arnottianum, and Syzygium montanum are reported for the first time. Roots of Berberis tinctoria, Mahonia leschenaultii (Berberidaceae), Elaeagnus latifolia (Elaeagnaceae), and Elaeocarpus oblongus (Elaeocarpaceae) lacked any fungal structures.  相似文献   
109.
This study presents the external mass transfer effects on the reduction of hexavalent chromium (Cr(VI)) using calcium alginate immobilized Bacillus sp. in a re-circulated packed bed batch reactor (RPBR). The effect of flow rate on the reduction Cr(VI) was studied. Theoretically calculated rate constants for various flow rates were analyzed using external film diffusion models and compared with experimental values. The external mass transfer coefficients for the bioconversion of Cr(VI) were also investigated. The external mass transfer effect was correlated with a model of the type JD = K Re−(1−n). The model was tested with various K values and the mass transfer correlation JD = 5.7 Re−0.70 was found to predict the experimental data accurately. The proposed model would be useful for the design of industrial reactor and scale up.  相似文献   
110.
Nitrogen fertilization of roots enhances shoot growth in plants and cytokinins are known to initiate bud outgrowth in shoots. Is it possible that root-derived cytokinins may play a role in long-distance signaling for nitrogen availability in the promotion of sylleptic branching in hybrid poplar? Nitrogen fertilization in the form of 5 mM NH4NO3, KNO3 or NH4Cl was applied to roots of three hybrid poplar clones exhibiting contrasting degrees of sylleptic branching. Cytokinin (0.1-1 mM benzyladenine, BA) was applied directly to lateral buds of shoots. Glutamate, asparagine and glutamine were also applied as drops to buds or as foliar sprays. NH4NO3, KNO3 and NH4Cl all usually enhanced sylleptic branching within a week in the high sylleptic clone (11-11) but in four out of five trials there was no effect in the low sylleptic clone (47-174). NH4NO3 added directly to buds had no effect. Also, glutamate, asparagine and glutamine had no effect. However, 1 mM BA promoted lateral bud outgrowth in all three clones. These results are consistent with the long-distance nitrogen signaling hypothesis of Forde and Sakakibara wherein nitrogen is transduced to cytokinin via enhanced ipt activity in the roots and is translocated up the shoot with the subsequent promotion of leaf/bud outgrowth.  相似文献   
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