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31.
Changes in fluorescence and oxidation indices of soybean flour were studied during storage at 37, 50, and 60°C. The peroxide
value and 2-thiobarbituric acid value did not increase in proportion to the extent of oxidation. The front-surface fluorescence
of oxidized soybean flour had an excitation maximum around 350 nm and an emission maximum between 420 and 430 nm. The fluorescent
compounds were soluble in the organic phase of chloroform/methanol (2∶1, vol/vol) after addition of water, and the solution
showed excitation and emission maxima around 360 and 440 nm, respectively. The fluorescent compounds might have been produced
from interactions of oxidizing soybean oil with other constituents of soybean flour. The fluorescence intensity in the organic
phase increased steadily throughout the storage period. Fluorescence kinetics of soybean flour oxidation showed a zero-order
increase, and the rate followed an Arrhenius relationship with an activation energy of 47.8 kJ/mol. These results suggest
that analysis of fluorescence intensity in the organic phase is a useful indicator for determination of the oxidative deterioration
of soybean flour. 相似文献
32.
Hso-Chi Chaung Chin-Dong Chang Pi-Hang Chen Chia-Jung Chang Shyh-Hwa Liu Chih-Cheng Chen 《Food chemistry》2013
Fish oil during early postnatal period may modulate the impact of oxidative stress in the developing brain and thus improve memory and cognitive behaviour. This study investigated the impacts of docosahexaenoic acid (DHA, C22:6, n-3) and/or phosphatidylserine (PS) on antioxidant activities in vitro, and the beneficial effects of feeding with DHA and/or PS on antioxidant activities in brain and liver tissues and on the cognitive functions of the developing brain. Results indicated that DHA and/or PS significantly enhanced antioxidant activities and increased cell viabilities in vitro. Feeding with DHA and/or PS supplementation not only significantly improved escape latency of animals, but it also improved the oxidative parameters in the brain, enhanced glutathione peroxidase activity as well as reduced nitric mono-oxide levels in the liver. DHA and PS may serve to protect cells from oxidative stress and further improve learning and memory ability in vivo. 相似文献
33.
This study investigates the effects of adding anionic and nonionic surfactants to the scrubbing liquid during the absorption of naphthalene (Nap) using a wet scrubber. Both batch and continuous experiments were performed on a laboratory-scale packed tower scrubber by adding surfactants to the scrubbing liquid. An anionic surfactant sodium dodecyl sulfate (SDS) and two nonionic polyoxyethylene surfactants C10E4 [tetraethylene glycol mono(decyl ether)] and C14E8 [octaethylene glycol mono(tetradecyl ether)] were used. The concentrations of the surfactant solutions all exceeded the critical micelle concentration. The results of continuous experiments indicate that the efficiencies of removal of naphthalene by C10E4 and C14E8 were 75.0 and 71.9%, respectively, at a concentration of 1.0×10?2?M. The removal efficiency of naphthalene by SDS ranged from 6 to 39% at concentrations from 1.0×10?2 to 1.0×10?1?M under continuous scrubbing. In the batch experiments, the batch naphthalene absorption capacities were estimated to be 31.8?μg?Nap/g?C10E4, 12.9?μg?Nap/g?C14E8, and 2.4 μg Nap/g SDS. A comparison was also made among SDS, C10E4, and C14E8 in terms of cost, foaming, impact of wastewater, removal efficiency, and absorption capacity. 相似文献
34.
Vinyl polymer PTPA containing pendant triphenylamine chromophore, which possesses hole-transport characteristics, was used as a host material in green phosphorescent light-emitting diodes. The PL spectrum of PTPA showed an intrinsic peak (375 nm) attributed to triphenylamine groups and an excimer emission (440 nm). The PL and EL spectra of the blends [PTPA:Ir(ppy)3] showed dominant green emission attributed to Ir(ppy)3 due to efficient energy transfer from PTPA to Ir(ppy)3. The HOMO level of PTPA, estimated from cyclic voltammetric data, was −5.36 eV, which is higher than −5.8 eV of PVK owing to hole-affinity characteristics of the pendant triphenylamine groups. The best performance was obtained with the EL device (ITO/PEDOT:PSS/PTPA:Ir(ppy)3 (1 wt%):PBD (40 wt%)/Ca/Al), the maximal luminance and the maximal luminance efficiency were 8358 cd/m2 and 4.5 cd/A, respectively. The present study suggests that the polymer PTPA is versatile host materials for green phosphorescent polymer light-emitting diodes applications. 相似文献
35.
Ying-Hsien Huang Chih-Jen Chen Kuo-Shu Tang Jiunn-Ming Sheen Mao-Meng Tiao You-Lin Tain Chih-Cheng Chen En-Wei Chu Shih-Wen Li Hong-Ren Yu Li-Tung Huang 《International journal of molecular sciences》2016,17(3)
The objective of this study was to investigate cellular apoptosis in prenatal glucocorticoid overexposure and a postnatal high fat diet in rats. Pregnant Sprague-Dawley rats at gestational days 14 to 21 were administered saline (vehicle) or dexamethasone and weaned onto either a normal fat diet or a high fat diet for 180 days; in total four experimental groups were designated, i.e., vehicle treated group (VEH), dexamethasone treated group (DEX), vehicle treated plus high-fat diet (VHF), and dexamethasone treated plus high-fat diet (DHF). Chronic effects of prenatal liver programming were assessed at postnatal day 180. The apoptotic pathways involved proteins were analyzed by Western blotting for their expressions. Apoptosis and liver steatosis were also examined by histology. We found that liver steatosis and apoptosis were increased in the DHF, DEX, and VHF treated groups, and that the DHF treated group was increased at higher levels than the DEX and VHF treated groups. The expression of leptin was decreased more in the DHF treated group than in the DEX and VHF treated groups. Decreased peroxisome proliferator-activated receptor-gamma coactivator 1α, phosphoinositide-3-kinase, manganese superoxide dismutase and increased malondialdehyde expression levels were seen in DHF treated group relative to the DEX treated group. The DHF treated group exhibited higher levels of oxidative stress, apoptosis and liver steatosis than the DEX treated group. These results indicate that the environment of high-fat diet plays an important role in the development of liver injury after prenatal stress. 相似文献
36.
Chih-Cheng Chang Author Vitae Author Vitae Yuh-Jye Lee Author Vitae 《Pattern recognition》2011,44(6):1235-1244
This paper extends the previous work in smooth support vector machine (SSVM) from binary to k-class classification based on a single-machine approach and call it multi-class smooth SVM (MSSVM). This study implements MSSVM for a ternary classification problem and labels it as TSSVM. For the case k>3, this study proposes a one-vs.-one-vs.-rest (OOR) scheme that decomposes the problem into k(k−1)/2 ternary classification subproblems based on the assumption of ternary voting games. Thus, the k-class classification problem can be solved via a series of TSSVMs. The numerical experiments in this study compare the classification accuracy for TSSVM/OOR, one-vs.-one, one-vs.-rest schemes on nine UCI datasets. Results show that TSSVM/OOR outperforms the one-vs.-one and one-vs.-rest for all datasets. This study includes further error analyses to emphasize that the prediction confidence of OOR is significantly higher than the one-vs.-one scheme. Due to the nature of OOR design, it can detect the hidden (unknown) class directly. This study includes a “leave-one-class-out” experiment on the pendigits dataset to demonstrate the detection ability of the proposed OOR method for hidden classes. Results show that OOR performs significantly better than one-vs.-one and one-vs.-rest in the hidden-class detection rate. 相似文献
37.
The Center for Measurement Standards (CMS) developed a laminar flow meter (LFM) as a transfer standard. This LFM consists
of a single, straight glass capillary or multiple straight glass capillaries connected in parallel. Two gauges and one thermometer
measure the inlet/outlet pressure and inlet temperature, respectively, and the differential pressure was restricted to between
2 kPa and 100 kPa. The glass capillaries were manufactured by laser machining, which resulting in consistent inner diameter
and straight flow path. Characteristics of the glass material also prevented the capillary from bending during installation.
The LFMs were calibrated against the CMS piston prover primary standard and the calibration data were fitted using a theoretical
LFM model and a 2nd order polynomial. The turndown ratio of this approach was higher than 20 and the residuals were within
0.11%. The reproducibility/repeatability within 0.03% indicated that this LFM could be used as a transfer standard. Measurement
with dry air demonstrated that these four LFE meters could span flows from 0.8 to 986 μmol/s within the deviation of ± 0.15%
(1μmol/s is 1.3 cm3/min at 0°C and 101.325 kPa). Additional measurement with nitrogen demonstrated the feasibility of measurement with multiple
gases. 相似文献
38.
Shou-Chih Lo Nai-Wun Luo Jhih-Siao Gao Chih-Cheng Tseng 《Wireless Personal Communications》2014,74(4):1329-1344
Delay-Tolerant Networks (DTNs) are special types of network environments that are subject to delays and disruptions. Most research efforts on the DTN routing problem are focused on unicast routing but not multicast routing. Moreover existing DTN multicasting approaches are not efficient and flexible. In this paper, we propose a new multicast routing approach which can not only achieve a high delivery rate but also adapt to network conditions. Most importantly, our proposed approach need not maintain group membership. In other words, any interested users can freely join and leave any multicast groups, and this feature suitably fits into DTN environments. 相似文献
39.
Hung-Huan Liu Wei-Hsiang Lo Chih-Cheng Tseng Haw-Yun Shin 《Wireless Personal Communications》2014,79(1):611-627
Past studies of WiFi-based indoor positioning systems (IPS) have mainly been divided into three types of positioning: proximity, trilateration, and scene analysis. This paper proposes a WiFi-based weighted screening method (WSM) to improve displacement error in trilateration. WSM is designed for part of pedestrian navigation in indoor environment which most likely use smart phone as the WiFi signal detector. Thus the less computational power consuming, irregular deploying position of APs and the irregular RSSI variation are all take into consideration when designing WSM. Experiment results show that this method performs better than conventional matrix method and the error correction algorithm, one trilateration in IPS. 相似文献
40.
Inspection plays an important role in the semiconductor industry. In this paper, we focus on the inspection task after wire bonding in packaging. The purpose of wire bonding (W/B) is to connect the bond pads with the lead fingers. Two major types of defects are (1) bonding line missing and (2) bonding line breakage. The numbers of bonding lines and bonding balls are used as the features for defect classification. The proposed method consists of image preprocessing, orientation determination, connection detection, bonding line detection, bonding ball detection, and defect classification. The proposed method is simple and fast. The experimental results show that the proposed method can detect the defects effectively. 相似文献