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51.
The essential oil of Salvia potentillifolia was analysed by GC and GC–MS. Totally, 123 components were detected in both hydrodistilled and steam-distilled oils, α- and β-pinenes being major compounds. The antioxidant activities were determined by using complementary tests, namely, DPPH radical-scavenging, β-carotene-linoleic acid and reducing power assays. The ethanol extract also showed better activity (IC50 = 69.4 ± 0.99 μg/ml) than that of BHT in the DPPH system, and showed great lipid peroxidation inhibition in the β-carotene-linoleic acid system (IC50 = 30.4 ± 0.50 μg/ml). The essential oil showed meaningful butyrylcholinesterase activity (65.7 ± 0.21%), and α-pinene showed high acetylcholinesterase inhibitory activity (IC50 = 86.2 ± 0.96 μM) while β-pinene was inactive. Antimicrobial activity was also investigated on several microorganisms, and the essential oil showed high activity against Bacillus subtilis and B. cereus. It also exhibited remarkable anticandidal activity against Candida albicans and C. tropicalis with MIC values of 18.5 and 15.5 μg/ml, respectively, while α- and β-pinenes showed moderate activity.  相似文献   
52.
The mechanical properties (microhardness, tensile strength) of alloys are controlled by their microstructure, which depends strongly on temperature gradient (G) and growth rate (V). Thus, it is important to understand the relationships among G, V and microstructure (rod eutectic) of Sn–Ag solders. The Sn–3.5 wt% Ag eutectic alloy was directionally solidified upward with a constant growth rate, V (16.5 μm/s) at different temperature gradients, G (1.43–4.28 K/mm) and with a constant temperature gradient, G (3.93 K/mm) at different growth rates, V (8.3–500 μm/s) in a Bridgman–type directional solidification furnace. The rod spacings (λ) have been measured from both longitudinal section (parallel to the growth direction, λ L ) and transverse section (perpendicular to the growth direction, λ T ) of the samples. The undercooling values (ΔT) were calculated by using V, λ and system parameters (K 1 and K 2). It was found that the values of λ (λ T , λ L ) decrease while V and G are increasing. The relationships between rod spacing and solidification parameters (G and V) were obtained by linear regression analysis. The dependences of eutectic spacings λ on undercooling (ΔT) are also analyzed. λ2 V, λΔT, ΔTV −0.5 and ΔTG −0.5 values were determined by using λ, ΔT, V and G values. The results obtained in this work are compared with the Jackson–Hunt eutectic theory and the similar experimental works. The experimental l\textT 2 \textV \lambda_{\text{T}}^{ 2} {\text{V}} value (159.3 μm3/s) is slightly lower than the result 174.6 μm3/s calculated from Jackson–Hunt eutectic theory.  相似文献   
53.
In this study, different formulations of chitosan (CS) and chitosan/sodium tripolyphosphate (CS/TPP) matrix solutions including β carotene were used as additives and edible coatings in hamburger patties, and the treatments were compared to control in terms of quality, oxidative and microbiological features of the patties. TBARS (2‐thiobarbituric acid reactive substances) values of almost all the treatments increased throughout storage at 4 °C for 8 days. (p < .05). On the last day of storage, the treatment including 5% CS/TPP with β carotene and all the coated treatments had lower TBARS values than the other treatments (p < .05). The comparison of different treatments including the solutions of chitosan or chitosan/TPP matrix containing β carotene showed that incorporation of solution as an edible coating was more effective in lipid oxidation and microbial growth than its utilization as an additive on quality of patties according to the results on last day of storage.

Practical applications

Using polymers loaded with antioxidant agents as additives or edible coatings in food products is one of the most popular scientific approaches in recent studies. In this study, hamburger patties were incorporated with chitosan/sodium tripolyphosphate (CS/TPP) matrix solution loaded with β carotene, CS/TPP matrix solution, pure chitosan solution and pure β carotene as additives and/or edible coatings. By this way, synergistic effects of β carotene with different formulations of chitosan (CS) and CS/TPP were also tested. The results showed that lipid oxidation and microbial growth in the coated patties were mostly lower than that of the other patties formulated with different additives on the last day of storage.  相似文献   
54.
Dendritic spacing can affect microsegregation profiles and also the formation of secondary phases within interdendritic regions, which influences the mechanical properties of cast structures. To understand dendritic spacings, it is important to understand the effects of growth rate and composition on primary dendrite arm spacing (λ 1) and secondary dendrite arm spacing (λ 2). In this study, aluminum alloys with concentrations of (1, 3, and 5 wt pct) Zn were directionally solidified upwards using a Bridgman-type directional solidification apparatus under a constant temperature gradient (10.3 K/mm), resulting in a wide range of growth rates (8.3–165.0 μm/s). Microstructural parameters, λ 1 and λ 2 were measured and expressed as functions of growth rate and composition using a linear regression analysis method. The values of λ 1 and λ 2 decreased with increasing growth rates. However, the values of λ 1 increased with increasing concentration of Zn in the Al-Zn alloy, but the values of λ 2 decreased systematically with an increased Zn concentration. In addition, a transition from a cellular to a dendritic structure was observed at a relatively low growth rate (16.5 μm/s) in this study of binary alloys. The experimental results were compared with predictive theoretical models as well as experimental works for dendritic spacing.  相似文献   
55.
Neutrophil‐to‐lymphocyte ratio (NLR) was introduced as a potential marker to determine inflammation in end‐stage renal disease (ESRD) patients. Recently, platelet‐to‐lymphocyte ratio (PLR) and NLR were found to positively correlated with inflammatory markers including tumor necrosis factor‐α (TNF‐α) and interleukin (IL)‐6 in cardiac and noncardiac patients. Data regarding PLR and its association with inflammation are lacking in hemodialysis (HD) and peritoneal dialysis (PD) patients. Hence, we aimed to determine the relationship between PLR, NLR, and inflammation in ESRD patients. This was a cross‐sectional study involving 62 ESRD patients (29 females, 33 males; mean age, 49.6 ± 14.6 years) receiving PD or HD for ≥6 months in the Dialysis Unit of Necmettin Erbakan University. PLR, NLR, C‐reactive protein, TNF‐α, IL‐6 levels were measured. PLR, NLR, serum high sensitive C‐reactive protein, IL‐6, and TNF‐α levels were significantly higher in PD patients when compared with HD patients. ESRD patients with PLR ≥ 140 had significantly higher NLR, IL‐6, and TNF‐α levels when compared to patients with PLR < 139. In the bivariate correlation analysis, PLR was positively correlated with NLR, IL‐6, and TNF‐α in this population. When we compared the association of PLR and NLR with IL‐6 (r = 0.371, P = 0.003 vs. r = 0.263, P = 0.04, respectively) and TNF‐α (r = 0.334, P = 0.008 vs. r = 0.273, P = 0.032, respectively), PLR was found to be superior to NLR in terms of inflammation in ESRD patients. Simple calculation of PLR can predict inflammation better than NLR in ESRD patients.  相似文献   
56.
In this study, temperature distribution in a CCD coated piston used in an HCCI engine was investigated and was guided by existing experimental results. A model based on experimental observations obtained from the experiments at Shell research center was developed by using finite element technique to investigate 3D thermal analyses for both clean and deposited piston. Effect of the CCD thickness on the temperature distribution was analyzed by comparing the results from the clean piston and deposited one. It was observed that the deposited surface temperature increases with increasing the thickness in a decreasing rate. Both aluminum and steel piston compared with each other in respect to the maximum temperature for the same CCD thicknesses, which were tn = 9 and tm = 30 in micro meters. Compared to the clean piston, maximum temperature on the top surface of the aluminum and steel metals diminish 6 °C and 9 °C respectively, because of CCD's relatively low heat transfer coefficient.  相似文献   
57.
Process management and innovation arguably remain among the concepts under focus of recent researches since there is no significantly outstanding method to measure and monitor the level of innovation in the manufacturing processes over a particular time period taking the fundamental activities of manufacturing processes into account. Although there are various studies relevant to process improvement, manufacturing processes are not focused on in the literature. This paper presents a novel performance indicator, called degree of process innovation, for monitoring and measuring innovation in manufacturing processes based on the four most important components among the fundamental activities of a manufacturing system. The components are namely Average Labour Utilisation, Cumulative Bottleneck Ratio, Unit Production Time and Unit Production Cost. The idea behind this approach has flourished on the basis of an indicator proposed in the literature to measure the general organisational improvements. The scope of that indicator has been narrowed down to manufacturing processes to accurately reflect the state of the manufacturing processes. The proposed approach has been verified with a case study in manufacturing industry, where each of the four sub-indicators was calculated based on the data provided and aggregated into the degree of process innovation. The innovation degree is successfully indicated.  相似文献   
58.
A rapid method for the determination of some important physicochemical properties in frying oils has been developed. Partial least square regression (PLS) calibration models were applied to the physicochemical parameters and near infrared spectroscopy (NIR) spectral data. PLS regression was used to find the NIR region and the data pre-processing method that give the best prediction of the chemical parameters. Calibration and validation were appropriated by leave one out cross validation and test set validation techniques for predicting free fatty acids (FFA), total polar materials (cTPM; measured by chromatographic method and iTPM measured by an instrumental method), viscosity and smoke point of the frying oil samples. For PLS models using the cross validation techniques, the best correlations (r) between NIR predicted data and the standard method data for iTPM in oils were 93.79 and root mean square error of prediction (RMSEP) values were 5.53. For PLS models using the test set validation techniques, the best correlations (r) between NIR predicted data and standard method data for FFA, cTPM, viscosity and smoke point in oils were 92.58, 94.61, 81.95 and 84.07 and RMSEP values were 0.121, 3.96, 22.30 and 8.74, respectively. In conclusion, NIR technique with chemometric analysis was found very effective in predicting frying oil quality changes.  相似文献   
59.
The interaction between soil and structure plays a crucial role on accurate determination of structures' seismic behavior. The assumption of fixed base structure has been commonly used in traditional design works, and the interaction between soil and structure is thus often neglected. In addition, historical masonry structures particularly built on elastic soil media may be significantly affected seismic behavior of the structure under earthquakes. In this research, the damage distribution on a historical masonry minaret is numerically investigated under horizontal earthquake ground motion. Alaca Mosque minaret was built in 1271 in Bolvadin district of Afyon province. The historical masonry minaret was chosen as the subject of the study. Nonlinear seismic time history analyses were conducted for fixed‐based and different soil properties under horizontal earthquake ground motion. The horizontal (East–West) component acceleration records of Dinar earthquake (Mw = 6.1) that took place on October 10, 1995, were used during the analyses. Maximum displacement, maximum/minimum principal stresses, and damage ratios were determined by nonlinear analyses performed considering fixed base and soil–structure interaction. The analysis results showed that soil–structure interaction had significant effect on the structural behavior of the minaret, such that, the minaret that was expected to get damage in the case of fixed base did not get any damage when soil–structure interaction was considered.  相似文献   
60.
In the present study, biochemical, chemical and texture changes in Tulum cheeses made using calf rennet and microbial rennets (Aspergillus niger protease and Rhizomucor miehei protease) were compared during ripening for up to 90 days. A total of 15 free fatty acids (FFAs) were detected in the cheese samples. The peroxide values (PV) of the cheeses increased significantly (P < 0.05) during ripening and the cheese made with calf rennet had the highest PV. Proteolysis in the cheeses increased as the ripening time increased. αs1‐casein and β‐casein degradation was higher in cheeses manufactured with R. miehei protease. Cheeses made with calf rennet were significantly (< 0.05) harder, more adhesive, more cohesive and more resilient than those made with microbial rennet.  相似文献   
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