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排序方式: 共有430条查询结果,搜索用时 15 毫秒
21.
Pooja Attri Drukshakshi Jodha Dimpi Gandhi Preeti Chanalia Suman Dhanda 《International Journal of Dairy Technology》2015,68(4):533-542
In vitro probiotic attributes of Pediococcus acidilactici, viz. tolerance to acidity and bile salt, phenol resistance, lactic acid production, antioxidant activity, cell surface hydrophobicity, lysozyme resistance and the presence of β‐galactosidase, proteolytic, lipase and peptidoglycan hydrolase activities, were studied. The strain was found to be rich in different proteolytic activities, β‐galactosidase and antioxidant activities, and produced lactic acid. The studies conducted support that P. acidilactici national collection of dairy cultures (NCDC) 252 is a potential probiotic for humans with all the essential basic probiotic properties. This testing is useful to gain insight into this strain and its mechanism of action. All these attributes add to its therapeutic importance and industrial significance. 相似文献
22.
An effort was made not only to demonstrate the performance of the self-cleaning coatings on building materials such as ceramic glazed tiles and glass windows, but also to understand the fundamental issues that are still alive in the field of self-cleaning surfaces based on photocatalysis. Nano TiO2 transparent thin films were generated by dip, spray and flow coating method. The present results indicate that the inconsistent results in the self-cleaning studies may be due to the effect of aggregation of model pollutant (methylene blue) dye on TiO2 surface. The effect of aliovalent metal ion (Ni2+, Fe3+, Nb5+) doping on phase formation, polymorphic transition, visible light absorbance and optical transparency of TiO2 film were investigated using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV visible absorption spectroscopy. The improved visible light activity of doped TiO2 thin film was correlated to the Ti(Ni/Fe)O3 phase formation, UV and visible light absorbance, variation in the optical energy band gap and the probable light scattering associated with grain size. 相似文献
23.
24.
Szabolcs Biro Tejash Gandhi Serji Amirkhanian 《Construction and Building Materials》2009,23(5):2080-2086
With the increasing awareness of the warm asphalt technology, it is imperative to study the properties of the binders containing the warm asphalt additives thoroughly, especially since not much research has been conducted on warm asphalt binder properties to date. Also, in the recent years, researchers have observed that the SHRP rutting parameter G1/sin δ is not very effective in predicting the rutting performance of binders, especially in case of modified binders. Zero shear viscosity (ZSV) has been evaluated to determine its effectiveness in predicting the rutting behavior of asphalt binders. Thus, in this paper, the ZSV of five asphalt binders with and without the warm asphalt additives, Asphamin® and Sasobit®, were calculated using the different models and test methods available in literature. From the test results, it was observed that the addition of the warm asphalt additives increased the ZSV of all the five binders used in this study. It was also observed that the different test methods gave different ZSV values, and that the selection of the test methods and the testing parameters are crucial parameters. 相似文献
25.
This paper explores nonlinear dynamic behavior of vibro-impacting tapered cantilever with tip mass with regard to frequency response analysis. A typical frequency response curve of vibro-impacting beams displays well-known resonance frequency shift along with a hysteric jump and drop phenomena. We did a comprehensive parametric analysis capturing the effects of taper, tip-mass, stop location, and gap on the non-smooth frequency response. Analysis is presented in a non-dimensional form useful for other similar cases. Simulation results are further validated with corresponding experimental results for a few cases. Illustrative comparison of simulation results for varying parameters brings out several interesting aspects of variation in the nonlinear behavior. 相似文献
26.
V. N. Aju kumar O. P. Gandhi 《Quality and Reliability Engineering International》2011,27(8):1145-1172
Assessment of human error in maintenance requires identification of the contributing factors that lead to human error(s). These factors are called human error inducing factors (HEIFs), which take into consideration both the active and latent error contributing aspects related to man, machine and environment. A systems approach of the Graph Theory is applied in this paper for quantifying human error in maintenance activities that models the identified factors and their interactions/interrelationships in terms of human error digraph. The nodes in the digraph represent the HEIFs and the edges represent their interrelationships. The digraph is converted into an equivalent matrix and an expression based on this is developed, which is characteristic of the human error in maintenance. This expression is used to evaluate a human error index by substituting the numerical value of the factors and their interrelations. The index is a measure of the human error potential involved in the maintenance of systems. A higher value of index indicates that the error likelihood is more for the associated tasks, and more efforts are required to make the system less prone to human error. The proposed methodology is illustrated using a case study. The approach is anticipated to play a significant role in identifying sources of human errors and predicting their impact; and will help to integrate human factors during design stage with the objective of reducing human error in maintenance. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
27.
Ashish C Gandhi Hsuan-Jung Hung Po-Hsun Shih Chia-Liang Cheng Yuan-Ron Ma ShengYun Wu 《Nanoscale research letters》2010,5(3):581-586
In this work, we succeeded in preparing in-plane zinc oxide nanowires using a Ti-grid assisted by the chemical vapor deposition method. Optical spatial mapping of the Confocal Raman spectra was used to investigate the phonon and geometric properties of a single ZnO nanowire. The local optical results reveal a red shift in the non-polar E2 high frequency mode and width broadening along the growth direction, reflecting quantum-confinement in the radial direction. 相似文献
28.
Effect of Operational Parameters on Determination of Oxidative Stability Measured by Rancimat Method
Nilkanth Pawar Akash Purohit Kamal Gandhi R.R.B. Singh 《International Journal of Food Properties》2013,16(9):2082-2088
Operational parameters of Rancimat, including sample weight (3, 6, 9 g), airflow rate (10, 15, 20 L/h) and temperature (110, 120, 130°C) were evaluated to determine their effects on oxidative stability index, temperature coefficient, Q10 number, and shelf life prediction of ghee (anhydrous milk fat). These parameters showed statistically significant effects on the oxidative stability index. It was observed that when the sample weight and airflow rate at a given temperature were at saturated air condition, the oxidative stability indexes showed no significant differences (p < 0). As the temperature increased, oxidative stability index decreased and average coefficient of variation was minimal at 120°C. The conditions under which the ghee sample was saturated with air and had a relatively lower oxidative stability index, was with sample weight of 6 g, temperature at 120°C and an airflow rate of 15 L/h. Temperature coefficient and Q10 number were independent of sample weight and air flow rate, however, they had a significant effect on shelf life prediction of ghee. 相似文献
29.
Lower task persistence in smokers with schizophrenia as compared to non-psychiatric control smokers.
Steinberg Marc L.; Williams Jill M.; Gandhi Kunal K.; Foulds Jonathan; Brandon Thomas H. 《Canadian Metallurgical Quarterly》2010,24(4):724
One contributing factor to difficulty in quitting smoking may be task persistence, which can be viewed as a behavioral manifestation of distress tolerance, and describes the act of persisting in a difficult or effortful task. Task persistence was assessed in smokers with schizophrenia and schizoaffective disorder (SZ/SA; N = 71) and non-psychiatric controls (N = 78) before a quit attempt. These data support the hypothesis that smokers with SZ/SA display less task persistence than do non-psychiatric controls when persistence is measured via mirror tracing and a 2-item persistence measure. Lower persistence may partially explain the reduced smoking cessation successes of smokers with SZ/SA as compared to the general population. These data also replicate findings regarding relationships between histories of ability to quit smoking and task persistence and expand them to a new population of smokers. The absence of a diagnostic status by length of previous abstinence interaction suggests that the contribution of task persistence to smoking cessation is similar for smokers with and without schizophrenia. Future studies should evaluate the ability of task persistence to predict abstinence from cigarettes prospectively among smokers with schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
Kamal J. K. Gandhi Daniel W. Gilmore Robert A. Haack Steven A. Katovich Steven J. Krauth William J. Mattson John C. Zasada Steven J. Seybold 《Journal of chemical ecology》2009,35(12):1384-1410
From 2000 through 2003 we used semiochemical-baited traps in northeastern Minnesota, USA, to assess changes in assemblages
of subcortical forest insects after a catastrophic wind storm in 1999 and subsequent (1999–2000) fuel-reduction activities
(salvage-logging and prescribed-burning). We determined the regional efficacy of fifteen semiochemical blends (pheromones
and kairomones) as attractants for target and non-target subcortical insect species (Coleoptera: Anthribidae, Buprestidae,
Cerambycidae, Cleridae, Cucujidae, Curculionidae, Histeridae, Nemonychidae, Salpingidae, Scolytidae, Tenebrionidae, and Hymenoptera:
Siricidae). During the four summers, we trapped 86,471 subcortical insects (143 species) in baited and unbaited Lindgren funnel
traps, and 500 beetles (44 species) in baited and unbaited pitfall traps. We report 23 new state collection records of subcortical
insects from Minnesota. Trap catches of subcortical insects were greatest in the wind-disturbed areas 2 years after the event,
and declined thereafter. Similar trends were observed for subcortical insects in the burned areas. Both wind-disturbance and
burning increased the subcortical insect species richness and diversity on the landscape. The subcortical insect species compositions
of the salvaged and burned forest areas differed from those of the undisturbed and wind-disturbed areas. Trap catches of subcortical
insects in response to semiochemical treatments also varied with year of sampling and land-area treatment. The greatest diversity
of subcortical beetle species was in traps baited with attractants for the scolytids, Dendroctonus valens [(+)-α-pinene and (−)-β-pinene] and Dryocoetes spp. [exo-brevicomin and (−)-α-pinene], perhaps reflecting the generic nature of the baits. The most distinct species compositions
were collected in response to the woodborer and Dendroctonus simplex baits, whereas the species compositions in traps with the D. valens and Dryocoetes spp. baits, and the unbaited funnel trap were the most similar. The variation in trap catch with time and across landscapes
suggests that the responses of subcortical insects to semiochemicals are more complex than previously appreciated. 相似文献