Colorless distributed combustion (CDC) investigated here is focused on gas turbine combustion applications due to its significant benefits for, much reduced NO
x emissions and noise reduction, and ...significantly improved pattern factor. CDC is characterized by distributed reaction zone of combustion which leads to uniform thermal field and avoidance of hot spot regions to provide significant improvement in pattern factor, lower sound levels and reduced NO
x emission. Mixing between the combustion air and product gases to form hot and diluted oxidant prior to its mixing with the fuel is critical so that one must determine the most suitable mixing conditions to minimize the ignition delay. Spontaneous ignition of the fuel occurs to provide distributed reaction combustion conditions. The above requirements can be met with different configuration of fuel and air injections with carefully characterized flow field distribution within the combustion zone. This study examines four different sample configurations to achieve colorless distributed combustion conditions that reveal no visible color of the flame. They include a baseline diffusion flame configuration and three other configurations that provide conditions close to distributed combustion conditions. For all four modes same fuel and air injection diameters are used to examine the effect of flow field configuration on combustion characteristics. The results are compared from the four different configurations on flow field and fuel/air mixing using numerical simulations and with experiments using global flame signatures, exhaust emissions, acoustic signatures, and thermal field. Both numerical simulations and experiments are performed at a constant heat load of 25
kW, using methane as the fuel at atmospheric pressure using normal temperature air and fuel. Lower NO
x and CO emissions, better thermal field uniformity, and lower acoustic levels have been observed when the flame approached CDC mode as compared to the baseline case of a diffusion flame. The reaction zone is observed to be uniformly distributed over the entire combustor volume when the visible flame signatures approached CDC mode.
Abstract
Evaluating crop health and forecasting yields in the early stages are crucial for effective crop and market management during periods of biotic stress for both farmers and policymakers. ...Field experiments were conducted during 2017–18 and 2018–19 with objective to evaluate the effect of yellow rust on various biophysical parameters of 24 wheat cultivars, with varying levels of resistance to yellow rust and to develop machine learning (ML) models with improved accuracy for predicting yield by integrating thermal and RGB indices with crucial plant biophysical parameters. Results revealed that as the level of rust increased, so did the canopy temperature and there was a significant decrease in crop photosynthesis, transpiration, stomatal conductance, leaf area index, membrane stability index, relative leaf water content, and normalized difference vegetation index due to rust, and the reductions were directly correlated with levels of rust severity. The yield reduction in moderate resistant, low resistant and susceptible cultivars as compared to resistant cultivars, varied from 15.9–16.9%, 28.6–34.4% and 59–61.1%, respectively. The ML models were able to provide relatively accurate early yield estimates, with the accuracy increasing as the harvest approached. The yield prediction performance of the different ML models varied with the stage of the crop growth. Based on the validation output of different ML models, Cubist, PLS, and SpikeSlab models were found to be effective in predicting the wheat yield at an early stage (55-60 days after sowing) of crop growth. The KNN, Cubist, SLR, RF, SpikeSlab, XGB, GPR and PLS models were proved to be more useful in predicting the crop yield at the middle stage (70 days after sowing) of the crop, while RF, SpikeSlab, KNN, Cubist, ELNET, GPR, SLR, XGB and MARS models were found good to predict the crop yield at late stage (80 days after sowing). The study quantified the impact of different levels of rust severity on crop biophysical parameters and demonstrated the usefulness of remote sensing and biophysical parameters data integration using machine-learning models for early yield prediction under biotically stressed conditions.
Two morpholinium-based surface-active ionic liquids (SAILs) with aromatic counterions were synthesized, namely, n-dodecyl-n-methylmorpholinium salicylate C12mmorSal and ...n-dodecyl-n-methylmorpholinium 3-hydroxy-2-naphthoate C12mmor3-h-2-n, and explored their aggregation behavior in aqueous solutions systematically. Electrical conductivity, small-angle neutron scattering (SANS), surface tension (ST), and UV–vis spectroscopy measurements were employed to determine various thermodynamic, micellar, and interfacial parameters, like the degree of counterion binding (β), critical micelle concentration (CMC), minimum area per molecule (A min), surface excess concentration (Γmax), standard Gibbs free energy of adsorption (ΔG ad 0), aggregation number (N agg), standard Gibbs free energy of micellization (ΔG m 0), standard enthalpy of micelle formation (ΔH m 0), and the standard entropy of micellization (ΔS m 0) in an aqueous solution. Incorporating the aromatic counterions favors significantly excellent micellization properties over conventional halogenated SAILs such as C12mmorBr. SANS analysis revealed that upon changing the counterion from salicylate to 3-hydroxy-2-naphthoate, the structure changed from prolate ellipsoidal micelles to large unilamellar vesicles. Also, increasing the concentration in the case of C12mmorSal resulted in a lower aggregation number.
Abstract The objective of the present study was to assess the neuroprotective role of rutin (vitamin P) and delineate the mechanism of action. Recent evidence indicates that rutin exhibits ...antioxidant potential and protects the brain against various oxidative stressors. More precisely, the aim of the present study was to examine the modulating impacts of rutin against cognitive deficits and oxidative damage in intracerebroventricular-streptozotocin (ICV-STZ)–infused rats. Rats were injected bilaterally with ICV-STZ (3 mg/kg), whereas sham rats received the same volume of vehicle. After 2 weeks of streptozotocin (STZ) infusion, rats were tested for cognitive performance using Morris water maze tasks and thereafter euthanized for further biochemical, histopathological, and immunohistochemical studies. Rutin pretreatment (25 mg/kg, orally, once daily for 3 weeks) significantly attenuated thiobarbituric acid reactive substances (TBARS), activity of poly ADP-ribosyl polymerase, and nitrite level and decreased level of reduced glutathione (GSH) and activities of its dependent enzymes (glutathione peroxidase GPx and glutathione reductase GR) and catalase in the hippocampus of ICV-STZ rats. ICV-STZ rats showed significant cognitive deficits, which was improved significantly by rutin supplementation. The results indicate that rutin attenuates STZ-induced inflammation by reducing the expression of cyclooxygenase-2 (COX-2), glial fibrillary acidic protein (GFAP), interleukin-8 (IL-8), inducible nitric oxide synthase (iNOS), nuclear factor-kB, and preventing the morphological changes in hippocampus. The study thereby suggests the effectiveness of rutin in preventing cognitive deficits and might be beneficial for the treatment of sporadic dementia of Alzheimer type (SDAT).
► Demonstrated CDC flames at thermal intensity range of 53–85
MW/m
3
atm. ► Ultra low NO emissions for both non-premixed (∼4
ppm) and premixed (∼1
ppm) modes. ► Low CO emissions (∼30
ppm) for both ...non-premixed and premixed modes. ► Very low dynamic pressure fluctuations (<0.025%) suggesting stable combustion. ► Pressure drop <5% across the combustor at the desirable operational condition.
Combustion characteristics of colorless distributed combustion have been investigated for application to gas turbine combustors. Very high intensity distributed combustion has been shown for application to stationary gas turbine engines. Various configurations examined have revealed reverse cross-flow mode to be more favorable for desirable combustion characteristics. The reverse-cross flow geometry is further investigated experimentally at range thermal intensities from 53 to 85
MW/m
3
atm with specific focus on exhaust emissions, radical emission, global flame photographs and flowfield using novel but simplified geometry for easy transition to applications in gas turbine engine applications. The high combustion intensity demonstrated here is higher than that used in present stationary gas turbine engines. Numerical simulations are also performed and compared with the experiments for the new design configuration under non-reacting conditions. Ultra low NO
x
emissions are achieved for both the novel premixed (1
ppm) and non-premixed (4
ppm) combustion modes reported here. Carbon monoxide levels of about 30
ppm are achieved in both novel premixed and non-premixed modes of combustion with a pressure drop of less than 5% across the combustor at the favorable condition. Almost no visible flame color in the reaction zones are observed for both novel premixed and non-premixed modes with volume distributed combustion so that this mode is termed as colorless distributed combustion. This mode of volume distributed colorless combustion is dramatically different than that used in contemporary gas turbine combustion operating under lean premixed, lean direct injection or rich burn, quick quench lean burn gas turbine combustion.
IntroductionSchizophrenia is a chronic psychiatric illness with symptoms in positive, negative and cognitive domain.The interplay of dietary folic acid intake with common genetic variants that ...influence folate metabolism, has potential implications for Schizophrenia pathogenesis and treatment.Therefore, it’s deficiency has been identified as a risk factor for Schizophrenia through epidemiologic, biochemical and gene association studies.Objectives1-To assess the efficacy of folic acid supplementation on severity of symptoms and overall functional status of patients2-To assess the correlation of serum folate levels with symptom severity and overall functional status of patientsMethodsA randomized control trial study was carried out in the inpatient department of a psychiatric tertiary care centre on 40 participants (29 males and 11 females)who were between the ages of 18 – 55 years,met diagnostic criteria for Schizophrenia (ICD 10) and had at least 2 years of illness duration while those with a co-morbid psychiatric illness, medical illness and substance abuse were excluded. The participants were then randomly allocated into two groups (experimental Group A which received 5mg folic/day along with anti psychotic drugs and control Group B which received only anti psychotic drugs) and followed up for 3 months. Blood sample for measuring serum folate level was obtained from the experimental group at the beginning and at the end of the study period. Scales applied were Positive and Negative Syndrome Scale(PANSS) for symptom severity and Global Assessment of Functioning scale(GAF) for overall functional status.ResultsA significant difference (p value< 0.05) was observed in PANSS scores at the end of the study between experimental group and control group( table 1) and also in GAF scores between both the groups after 3 months(table 2). At the end of the study period,a strong negative correlation(r= -0.9) was found between serum folate level and total PANSS score in the experimental group (figure 1) while the correlation between GAF score and serum folate level was strongly positive (r= 0.8) (figure 2).Table 1PANSS (3 Month)Group A(n=20)Group B (n=20)P valuePositive16.8±2.8022.9±3.370.036Negative14.3±3.3215.1±2.610.18General17.95±2.5221.85±3.180.0001Total45.95±3.4158±3.490.00249Table 2GAFGroup A(n=20)Group B (n=20)P value0 MONTH23.25±3.4322.7±2.900.33 MONTH65.75±4.2244.9±7.090.0256Image:Image 2:ConclusionsOur study is among the few to use a randomized controlled study design for assessing the effect of folic acid supplementation on severity of symptoms and global functioning in Schizophrenia,strongly suggesting the use of folic acid as an adjuvant treatment for Schizophrenia.Disclosure of InterestNone Declared
•Sequential development of high intensity CDC combustor from 5 to 453MW/m3atm.•Ultra low NO and CO demonstrated at thermal intensity of 340MW/m3atm.•Proper positioning of reaction zone is critical ...for low NO and CO emission.•Residence time distribution governs CO emissions at same thermal intensity.•Enhanced mixing in cross flow with low NO emission.
This paper examines the development of ultra-low emission colorless distributed combustion (CDC) for gas turbines, operating at thermal intensity in the range of 5–453MW/m3atm. Higher thermal intensity combustors are desirable for increased performance with minimal increase in hardware costs in terms of both weight and volume of gas turbine combustors. Most land based gas turbine combustors operate at thermal intensity of about 15MW/m3atm but operation at higher intensity can provide increased performance. Design of high thermal intensity CDC combustor requires control of critical parameters, such as gas recirculation, fuel/oxidizer mixing, air preheats, and residence time distribution characteristics via proper selection of different air and fuel injection configurations to achieve desirable combustion characteristics. Initially, various flow field configurations were investigated at a low thermal intensity of 5MW/m3atm. This effort was followed by investigations at higher thermal intensity ranges of 20–40MW/m3atm by reducing the combustor volume for a forward flow configuration under more favorable novel non-premixed conditions. Further investigations were performed for a simpler combustor having single injection ports for air and fuel with detailed investigation of various flow field configurations performed at a thermal intensity of 28MW/m3atm. Further reduction in combustion volume resulted in thermal intensity of 57MW/m3atm. For the flow configurations investigated, reverse cross-flow configuration was found to give more favorable results with air injected from exit end and fuel injected in a cross-flow direction to the air flow. This reverse cross-flow geometry was investigated in detail by further reducing the combustor volume. Air injection diameter was increased to reduce the pressure drop across the combustor. The combustor was investigated at thermal intensity in the range of 53–85MW/m3atm. This geometry resulted in 4ppm NO emission and CO emissions of about 27ppm under novel non-premixed flow conditions at thermal intensity of 53MW/m3atm. The pressure drop at this operational point was less than 5% to meet the conventional combustor requirements. Further reduction in combustor volume resulted in very high thermal intensity in the range of 156–198MW/m3atm and at the most desirable operational point NO and CO emissions were 8ppm and 82ppm, respectively under novel non-premixed mode at a thermal intensity of 170MW/m3atm. Even further reduction in combustor volume resulted in combustor operation at ultra-high thermal intensity of 283–453MW/m3atm and at the desirable operating point the NO and CO emissions were 4ppm and 115ppm respectively at a thermal intensity of 340MW/m3atm. The sequential efforts reveal the possibility of significantly increasing the thermal intensity while still achieving desirable emission levels.
•Bohr magneton number.•Initial permeability.•Loss Factor.•Curietemperature.
This study investigates the magnetic properties of Ni0.55−xZn0.45CoxFe2O4 (x = 0.0, 0.15, 0.25, 0.35, 0.45, 0.55) ferrite ...nanoparticles synthesized via the green synthesis route using orange juice as a green reductant. The magnetocrystalline anisotropy constant (Ms) and the Bohr magneton number (nB) of the Ni-Zn ferrites increase linearly with an increase in the content of Co2+ ions. The magnetic properties such as Saturation magnetization, Coercive force, and remanence ratio (Mr / Ms) are determined. The Curie temperature for the studied ferrites is found to be reduced upon doping with cobalt ions and is considered as the weakening of the A-B exchange interaction.
Reliable and quick estimation of wheat yellow rust (WYR) severity in field is essential to manage the disease and minimize the losses. Field experiments were conducted during 2017-18 and 2018-19 to ...obtain visible and thermal images of 24 wheat cultivars having different levels of WYR resistance at critical growth stages. Machine learning (ML) models were constructed using the combinations of image indices (IN) and partial least square regression (PLS) scores of image indices with disease severity (DS) and Yeo-Johnson (YJ) transformed values of disease severity. The results revealed that 26 visible and 2 thermal indices considered in this study have significant correlations with WYR. The models performances were evaluated using four possible dataset combinations of (1) disease severity + indices, (2) disease severity + PLS scores of indices, (3) YJ transformed disease severity + indices, and (4) YJ transformed disease severity + PLS scores. Disease severity with image derived indices was found to be the best dataset for the prediction of WYR severity using machine learning models with an R
2
and d-index above 0.95 during calibration, while up to 0.67 and 0.87, respectively during validation. Cubist model with disease severity + indices dataset was the best to predict WYR severity, while the Gaussian process regression with YJ transformed disease severity + PLS scores dataset was the poorest predictor. The results obtained in the present study showed the potential of ML models for non-destructive prediction of WYR in field using visible and thermal imaging.
