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•Multi-layered T6100 surface shows high activity towards ORR.•Role of dangling σ bond and π electron network.•Operating potential is significantly high (0.48V) considering C1 as an ...active site.•Si-substitution shows over activity with a high overpotential value.
The electrocatalytic activity of T6100 surface containing both sp3 (C1) and sp2 (C2) hybridized carbon atoms is explored using first-principles density functional theory based approach. The top layered C1 atom of the surface is found to be more active towards the oxygen reduction reaction (ORR), as compared to that of C2 atom. This is attributed to the presence of dangling σ bond in the corresponding C1 atom, leading to the high electron density near the Ferrmi level. Whereas, the π electron in the top layered C2 atom forms a weak out of plane network. As estimated from free energy profile, the overpotential is much lower when C1 is considered as the active site and the final step i.e desorption of final OH− ion is found to be the potential determining step. We have also reported the effect of Si dopant on the catalytic activity of T6100 surface and explained the origin of high overpotential value in this case. Thus in this report, we propose a new metal-free catalyst i.e T6100 surface, having both sp2 (maintains the high metallicity needed to reduce ohmic loss) and sp3 (helps in capturing the upcoming molecules) hybridized carbon atoms, as a potential candidate for ORR.
This paper deals with the use of commercial CFD software in teaching graduate level computational fluid dynamics. FLUENT 6.3.26 was chosen as the CFD software to teach students the entire CFD process ...in a single course. The course objective is to help students to learn CFD, use it in some practical problems and analyze as well as validate the simulation results with published data to enhance their understanding of design issues related to flow problems. Apart from the basic concepts of CFD, students are exposed to grid generation software GAMBIT. They also learn to set up physical model, solver and post processing the results in FLUENT. After that they try to analyze the data independently to address some design issues based on the results.
The effect of buffalo follicular fluid (buFF) on follicular development, estrus response and luteal function was investigated in anoestrous does. Treatment with buFF (18
ml/doe) had no significant ...effect on the number of antral follicles of all class categories during the period of administration. However, after cessation of buFF treatment, the number of total antral follicles increased significantly with time (
P
<
0.003) as well as due to the treatment
×
time interaction (
P
<
0.02), without any influence on follicle size. Injection of buFF also caused a marked increase (
P
<
0.049) with time in the number of medium-sized follicles at cessation. Approximately 60 and 20% of buFF-treated anoestrous does showed behavioural and silent estrus, respectively, compared to none in the control. The mean interval between cessation of buFF treatment to onset of oestrus and oestrus duration was 67.0
±
18.5 and 17.0
±
3.6
h, respectively. Corpus lutea size varied between 4.6 and 5.8
mm with an average diameter of 5.2
±
0.3
mm. Only 33.3% of does showed serum progesterone levels above 1
ng/ml, while the remainder (66.7%) had below 0.5
ng/ml. Our results indicate that exogenous administration of buFF causes enhanced follicular activity following cessation of treatment, which results in behavioural oestrus and corpus luteum (CL) development in anoestrous does. CL development and its function is, however, inadequate in buFF-treated anoestrous does.
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•Thick and thin scale formation over inside wall of tube promoted local overheating.•Prolong exposure of tube material under high stress and temperature caused creep and material ...softening leading to reduction in wall thickness.•Under high hoop stress at that elevated temperature, thinned wall material ultimately failed exhibiting ‘fish mouth opening’.
Cause of failure of two adjacent super heater tubes made of Cr-Mo steel of a coal based 60MW thermal power plant has been portrayed in present investigation. Oxide deposits were found on internal surface of tubes. Deposits created significant resistance to heat transfer and resulted in undesirable rise in component temperature. This situation, in turn, aggravated the condition of gas side that was exposed to high temperature. Localized heating coarsened carbides as well as propelled precipitation of new brittle phases along grain boundary resulting in embrittlement of tube material. Continuous exposure to high temperature softened the tube material and tube wall was thinned down with bulging toward outside. Creep void formation along grain boundary was observed and steered intergranular cracking. All these effects contributed synergistically and tubes were failed ultimately due to overload under high Hoop stress.
Employing Western blot analysis, we investigated the effect of maternal uterine artery ligation causing uteroplacental insufficiency with asymmetrical intrauterine growth restriction (IUGR) upon ...fetal (22d) and postnatal (1d, 7d, 14d and 21d) brain (Glut 1 and Glut 3) and skeletal muscle (Glut 1 and Glut 4) glucose transporter protein concentrations. IUGR was associated with a ∼42% decline in fetal plasma glucose (
p<0.05) and a ∼25% decrease in fetal body weights (
p<0.05) with no change in brain weights when compared to the sham operated controls (SHAM). In addition, IUGR caused a ∼45% increase in fetal brain Glut 1 (55 kDa) with no change in Glut 3 (50 kDa) protein concentrations. This fetal brain Glut 1 change persisted, though marginal, through postnatal suckling stages of development (1d–21d), with no concomitant change in brain Glut 3 levels at day 1. In contrast, in the absence of a change in fetal skeletal muscle Glut 1 levels (48 kDa), a 70% increase was observed in the 1d IUGR with no concomitant change in either fetal or postnatal Glut 4 levels (45 kDa). The change in skeletal muscle Glut 1 levels normalized by d7 of age. We conclude that IUGR with hypoglycemia led to a compensatory increase in brain and skeletal muscle Glut 1 concentrations with a change in the brain preceding that of the skeletal muscle. Since Glut 1 is the isoform of proliferating cells, fetal brain weight changes were not as pronounced as the decline in somatic weight. The increase in Glut 1 may be protective against glucose deprivation in proliferating fetal brain cells and postnatal skeletal myocytes which exhibit `catch-up growth', thereby preserving the specialized function mediated by Glut 3 and Glut 4 towards maintaining the intracellular glucose milieu.
A wide variety of manifestations is presented in patients with Gaucher's disease (GD), including bone, haematology and visceral disturbances. This study was conducted to ascertain the main ...maxillofacial abnormalities by means of clinical survey, panoramic and cone beam CT (CBCT); to compare the patient's group with an age-sex matched control group; and to correlate clinical and radiological data.
Ten patients previously diagnosed with GD were submitted to clinical and radiological surveys (CBCT and panoramic radiographs). The examination consisted of anamnesis, extra- and intraoral examinations and analyses of each patient's records. Imaging data were collected from the point of view of 3 observers, and the results compared with a healthy group (20 individuals) by means of statistical analysis (Fisher's exact test).
Gaucher patients had significantly more manifestations than otherwise healthy carriers. The most prevalent findings were enlarged marrow spaces, generalized osteopenia and effacement of jaw structures (mandibular canal, lamina dura and mental foramen). Here we describe a case in which thickening of the maxillary sinus mucosa was observed on CBCT rather than opacification of the sinus as seen on panoramic radiographs. Pathological fractures, root resorption and delay on tooth eruption were not observed.
A poor relationship could be observed between clinical and radiological data. Patients showed important bone manifestations, which require careful diagnostic and surgical planning whenever necessary. Although panoramic radiographs have shown significant differences, CBCT is more effective in pointing out differences between patients and a control group, thus showing it as an important tool for evaluation of Gaucher patients.
Ni-SiOd2 and Co-SiOd2 nanocomposites were prepared by the reduction of NiCld2- and CoCld2-containing SiOd2 gels under non-isothermal conditions. The effect of heating rate, temperature and metal ...chloride concentration were assessed using statistically planned experimental designs.
In the present article we study the rate of convergence problem of Fourier series by Deferred Cesàro Mean in the generalized Hölder metric (Hp(w)) space which was earlier introduced by Das, Nath and ...Ray.
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