Seed processing technologies are essential for seed safety and functionality through protection of physicochemical quality, pathogen inactivation, aflatoxin detoxification and alleviation of mutagenicity. Design of a pilot-scale unit of pulsed electric fields (PEF) to treat sesame seeds with respect to quality parameters, Aspergillus parasiticus inactivation and aflatoxin reduction as well as alleviation of aflatoxin mutagenicity were prompted in this study. PEF energy ranged from 0.97 to 17.28 J achieved maximum reductions of peroxide value and acidity number of 67.4 and 85.7%, respectively, and did not change color L*, a*, b* and hue values. A 60% reduction of A. parasiticus counts occurred at the maximum PEF energy. Aflatoxins G1, G2, B1, and B2 contents decreased by 94.7, 92.7, 86.9, and 98.7%, respectively. Except for the samples treated by 2.16 J with 100 μg/plate and by 6.80 J with 10 μg/plate, PEF treatment provided elimination of aflatoxin mutagenity. It is concluded that PEF treatment can be used to treat sesame seeds with preservation of physicochemical properties, inactivation of A. parasiticus and decomposition of aflatoxins with reduced mutagenicity. 相似文献
The conversion of chromite ore from iskenderun region into chromate was investigated. Firstly, the chromite ore was analysed using conventional chemical methods. Then, the effect of some parameters such as roasting time, temperature and the amount of additives on the conversion efficiency to the chromate was examined. The optimum roasting conditions were determined as 300°C, 2 hours, 10 times the stoichiometrically required amounts of NaClO3 and 6 times the stoichiometrically required amounts of KOH. Under these conditions, the maximum recovery of chromate was found to be 100%. The product obtained from the roasting process was leached with water to produce a clean chromate solution. The effect of temperature and solid/liquid (S/L) ratio was investigated in the water leaching experiments. The optimum experimental results obtained were 100% at a 1:5 solid to water ratio at 25°C and 20 min leaching period. The chromate solution was purified using conventional purification processes. 相似文献
Degradation of 4-chloro-2-methylphenol (PCOC), a refractory toxic chemical emitted to the environment from the industrial production of phenoxy herbicides was studied in aqueous solution. Electro-Fenton and photoelectro-Fenton processes were used as the degradation methods. H2O2, produced by the reduction of oxygen at carbon cathode reacted with dissolved metal ions to form hydroxyl radicals, which in turn reacted with PCOC sequentially to degrade the aromatic ring. The effects of using different [Fe2+]/[PCOC]0 and the effect of replacing Fe2+ by Mn2+ ion have been examined. It was found that degradation rate was increased with increasing [Fe2+]/[PCOC]0 ratio from 2 to 4. However, the total charge utilized during the treatment was also increased. The efficiency of PCOC degradation was observed to be higher when Mn2+ was used as the catalyst. The mineralization of aqueous solutions of PCOC, withdrawn from the reactor at certain time interval, has been followed by total organic carbon (TOC) decay and dechlorination. A fast and complete degradation of the aromatic ring was achieved in photoelectro-Fenton system. 41.7% TOC decay and complete dechlorination were observed by consuming only 141.4 C electrical charge during a 300 min photoelectron-Fenton treatment. In the case of electro-Fenton system, 280.7 C electrical charge was consumed during 450 min of electrolysis to attain a similar degradation of PCOC. 14.9% TOC removal and 89.3% dechlorination have been obtained in this system under the applied conditions. 相似文献
Modification of chitosan by grafting of vinyl butyrate was carried out in homogeneous phase using potassium persulfate as
redox initator and 1.5% acetic acid as solvent. The percent grafting and grafting efficiency were analysed and the high grafting
efficiency up to 94% was observed. The effects of reaction variables such as monomer concentration, initiator concentration,
temperature and reaction time were investigated. It was observed that the solubility of chitosan was markedly reduced after
grafting with vinyl butyrate. The grafted product is insoluble in common organic solvents as well in dilute organic and inorganic
acids. Characterization of the graft copolymers were carried out by using Fourier Transform Infrared Spectroscopy (FTIR),
Differential Scanning Calorimetry (DSC) and Scanning Electron Microscopy (SEM) technics. Characteristic signal of carbonyl
group was observed at 1,731 cm−1 which belongs to the poly vinyl butyrate segments in the graft copolymer. The melting transition of the chitosan main chain
in the copolymer shifted to 124°C from its original value 101°C. In addition to these, we have also studied topology of the
graft copolymer and the SEM micrograph showed continuous homogenous matrix which means there is no phase separation. 相似文献
In this paper, we investigate visual similarity for high dynamic range (HDR) images. We collect crowdsourcing data through a web-based experimental interface, in which the participants are asked to choose one of the two candidate images as being more similar to the query image. Triplets forming the query-and-candidates sets are obtained by random sampling from existing HDR data sets. Experimental control factors include choice of tone mapping operator (TMO), choice of distance metric, and choice of image feature. The image features that we experiment with are chosen from the features that are commonly used in the usual low dynamic range setting including features learned via Convolutional Neural Networks. The set of image features also includes combined features where the combination coefficients are estimated using logistic regression. We compute correlations between human judgments and quantitative features to understand how much each feature contributes to visual similarity. Combined features yield nearly 84% agreement with human judgments when applied on tone mapped images. Though we observed that using common features directly on raw or linearly scaled HDR images yield subpar correlation estimates compared to using them on tone mapped HDR images, we did not observe significant effect due to the choice of TMO on the estimates. As an application, we propose an improvement to style-based tone mapping for more correctly imparting desired styles to HDR images with different characteristics.
In this paper, we propose a new multicast tree framework to be used in peer-to-peer (P2P) live video streaming systems. The proposed system, adapts the tree links under high peer churn and runs in a totally distributed manner. In order to provide this dynamism and seamless streaming at the same time, we propose a cross layer design involving scalable video codec, backup parents and hierarchical clusters. The performance of the system is measured in real world environment PlanetLab that has nodes distributed all over the world. The experiments show that the proposed system provides high quality of experience (QoE) in terms of Peak Signal to Noise Ratio (PSNR), playback delay and duration of pauses. The proposed system also provides incentive mechanism to its users. 相似文献
Hub location problems deal with finding the location of hub facilities and with the allocation of demand nodes to these located hub facilities. In this paper, we study the single allocation hub covering problem over incomplete hub networks and propose an integer programming formulation to this end. The aim of our model is to find the location of hubs, the hub links to be established between the located hubs, and the allocation of non-hub nodes to the located hub nodes such that the travel time between any origin–destination pair is within a given time bound. We present an efficient heuristic based on tabu search and test the performance of our heuristic on the CAB data set and on the Turkish network. 相似文献
We present a simple and robust feature preserving image regularization by letting local region measures modulate the diffusivity.
The purpose of this modulation is to disambiguate low level cues in early vision. We interpret the Ambrosio-Tortorelli approximation
of the Mumford-Shah model as a system with modulatory feedback and utilize this interpretation to integrate high level information
into the regularization process. The method does not require any prior model or learning; the high level information is extracted
from local regions and fed back to the regularization step. An important characteristic of the method is that both negative
and positive feedback can be simultaneously used without creating oscillations. Experiments performed with both gray and color
natural images demonstrate the potential of the method under difficult noise types, non-uniform contrast, existence of multi-scale
patterns and textures.
Smart cards are used in information technologies as portable integrated devices with data storage and data processing capabilities. As in other fields, smart card use in health systems became popular due to their increased capacity and performance. Their efficient use with easy and fast data access facilities leads to implementation particularly widespread in security systems. In this paper, a smart card based healthcare information system is developed. The system uses smart card for personal identification and transfer of health data and provides data communication via a distributed protocol which is particularly developed for this study. Two smart card software modules are implemented that run on patient and healthcare professional smart cards, respectively. In addition to personal information, general health information about the patient is also loaded to patient smart card. Health care providers use their own smart cards to be authenticated on the system and to access data on patient cards. Encryption keys and digital signature keys stored on smart cards of the system are used for secure and authenticated data communication between clients and database servers over distributed object protocol. System is developed on Java platform by using object oriented architecture and design patterns. 相似文献