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51.
Ecofriendly ultrasonic textile dyeing with natural dyes such as Acacia catechu and Tectona grandis show better and faster dye uptake after enzyme pretreatment on cotton fabric, and results of dyeing are better than metal mordanted fabric. It is observed that there is marked improvement in wash-fastness and light-fastness. The role of enzyme pretreatment is primarily for better absorbency, adherence and dyeability of these dyes on cotton fabric, thereby completely replacing metal mordants with enzyme for adherence of natural dyes on cotton. Scanning electron microscopy show surface characteristics at different stages of dyeing. The effect of sonication on the dyeing is compared with conventional heating. The study also shows enhancement in CIELab values.  相似文献   
52.
In the present study series of aqueous polyurethane (PU)/ZnO hybrid dispersions were prepared using dimethylolpropionic acid (bis-MPA) as an ionic center. For this, NCO terminated PU prepolymers with pendent acid groups were prepared first, then different concentrations of nano ZnO powder was incorporated into the PU matrix. The hybrid dispersions were prepared by adding required amount of triethylamine (TEA), water and chain extender. The prepared PU/ZnO hybrid dispersions were casted in a Teflon petri dish and the dried films were used for TGA, DMTA, SEM, gel content and contact angle measurements. The phase mixing behavior was studied from FT-IR peak deconvolution technique and DMTA analysis and the result suggests that phase mixing increases with ZnO content. The DMTA data suggest that the phase mixing and soft segment glass transition increases but storage modulus decreases with increasing with ZnO content. The FT-IR deconvolution result supports to the DMTA analysis. The coating properties like adhesive strength, water absorption, contact angle, gel content and corrosion resistance of the hybrid coatings were also evaluated.  相似文献   
53.
Gum xanthan/psyllium-based nanocomposite was prepared by microwave-assisted synthetic method for the removal of toxic Malachite green (MG) dye from aqueous solutions. The nanocomposite was prepared by in situ incorporation of the K2Zn3[Fe(CN)6]·9H2O nanoparticles into the semi-IPN matrix in the presence of ammonium persulphate and glutaraldehyde as initiator-crosslinker system. Liquid uptake efficacy of the hybrid superabsorbent was enhanced through the optimization of different reaction conditions, including APS = 0.027 mol L?1; glutaraldehyde = 0.053 × 10?3 mol L?1; solvent = 8.0 mL; acrylic acid = 10.928 mol L?1; pH 7.0; reaction time = 60 s and microwave power = 100 % and its thermal behavior was evaluated using TGA-DTG-DTA technique. Candidate nanocomposite was characterized by FTIR, SEM, XRD and UV–visible spectroscopic methods. Various optimized parameters for the efficient removal (83 %) of the Malachite green were adsorbent dose of 800 mg, 14 mg L?1 initial dye concentration and contact time of 28 h. Further, Langmuir and Freundlich adsorption isotherms showed good applicability in adsorption process of MG onto the nanocomposite with maximum adsorption efficiency of 3.21 mg g?1. However, for Freundlich isotherm, R 2 was around 0.9947 and value of 1/n was less than 1 for the synthesized nanocomposite which indicated that the Freundlich isotherm was more favorable than Langmuir isotherm model along with its usability for wide range of dye concentrations. The nanocomposite was found to be a potential product for dye removal from waste water and could prove to be a boon for textile sector.  相似文献   
54.
This paper presents a production-inventory model in a single-vendor single-buyer system for decaying items which deplete with constant decay rate. It is assumed that the lead time demand follows a normal distribution and shortages are backordered. Also, buyer's lead time can be reduced at an added cost. A model has been formulated to find the optimal order quantity, lead time and the number of shipments from the vendor to the buyer during one production cycle while minimising the total expected cost per unit time of the vendor-buyer integrated system. It is often difficult to estimate the stock-out cost in inventory systems. Therefore, instead of having a stock-out term in the objective function, a service level constraint is included in the model. Due to mathematical complexities involved, it is difficult to establish the solutions analytically. An iterative procedure is developed to find the optimal solution using LINGO 10, and a numerical example is given to illustrate the results of the proposed model. Furthermore, the effects of key parameters are also studied to provide the insight into the structure of the solution. In addition, the savings of buyer and vendor are investigated from implementation of joint optimisation model over the model in which they minimise their own cost independently.  相似文献   
55.
An heuristic methodology has been developed in the present work for configuring a mixed (hybrid) uni/bidirectional flow path for an AGV material handling system. The given unidirectional flow path layout, material flow intensities and vehicle travelling time matrix among various processing centres are taken as input information to this technique. A multiplicative function of material flow intensities between any two centres is used as a criterion for selectively configuring a path as a bidirectional one. The highest such product indicates that the shorter path between that pair of centres is a strong candidate for being configured as bidirectional. The heuristic has been applied to an illustrative FMS and various alternate flow path designs have been obtained. Simulation is then performed with the aim of comparing the productive potentials of the facility when it is operated on either unidirectional, or mixed uni/bidirectional, or allbidirectional flow path design alternatives. The benefits of bidirectional flows over unidirectional counterpart are significant in terms of system throughput rates and optimal AGV fleet sizes. However, traffic control becomes an important issue as vehicle interference and blocking increases with increase in bidirectionality in the network. The decision related to location and capacity planning of vehicle buffering zones is also addressed.  相似文献   
56.

Recommendation System is one of such solutions to overcome information overload issues and to identify products most relevant to users and provide suggestions to users for items they might be interested in consuming or elements matching their needs. The significant challenge of several recommendation approaches is that they suggested a huge number of things to the target user. But the exciting items, according to the target user, are seen at the bottom of the recommended list. The proposed approach has improved the quality of recommendations by implementing some of the unique features in the new framework of auto encoder called semi-autoencoder, which contains the rating information as well as some additional information of users. Autoencoder is widely used in the recommender system because it gives the best result for feature extraction, dimensionality reduction, regeneration of data, and a better understanding of the user’s characteristics. The experimental results are compared with some established popular methods using precision, recall, and F-measure evaluation measures. Users generally don’t want to see lots of suggestions. With its six building blocks, the proposed approach gives better performance for the top 10 recommendations compared to other well-known methods.

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57.
Tea (both green and black) is consumed throughout the world, both for pleasure and therapeutic purposes. Most people will be unaware of their involuntary exposure to residues of pesticides lingering in processed tea and so possibly transferring into infusions of tea. The purpose of this work was to study the effect of green tea and orthodox black tea manufacturing processes on the fate of pesticides sprayed onto tea bushes (Camellia sinensis). The fates of residues of dimethoate, quinalphos, dicofol and deltamethrin in these two different types of tea manufacturing processes were compared. For black tea, the manufacturing process involves leaf harvesting, withering, rolling, fermentation and drying; and for green tea, leaf harvesting, microwave heating, rolling and drying. The two processes resulted in the same concentration factor of plant material into the dried commodity, while the decreases in residue levels were different for different pesticides. Initial microwave heating and dehydration in the green tea manufacturing process resulted in greater loss of pesticide residues than did withering and dehydration in black tea; no significant reduction in residue level resulted from the rolling and fermentation steps in black tea. Residue levels in both green and black teas were reduced during final drying. Copyright © 2004 Society of Chemical Industry  相似文献   
58.
Fenvalerate residue level and dissipation in tea and in its infusion   总被引:1,自引:0,他引:1  
Fenvalerate is a non-systemic insecticide/acaricide used in controlling a wide range of pests, including those resistant to organochlorine, organophosphorus and carbamate insecticides. The study investigated the dissipation behaviour (residue level) of fenvalerate in tea and its transfer during infusion. Fenvalerate was applied on tea crop at two dosages, 100 and 200 g a.i. ha-1 (recommended and double the recommended) in the dry and wet seasons under field conditions. Samples (green tea shoots, made tea, its infusion and spent leaves) were analysed for fenvalerate by high-performance liquid chromatography using diode array detection. The residue dissipated faster in the wet season than in the dry season. Seven days after the treatment (normal round of plucking) the residues observed in the green shoots at the two dosages were 0.5 ± 0.01, 1.1 ± 0.01 and 0.4 ± 0.02, 0.9 ± 0.01 mg kg-1 in the dry and wet seasons, respectively. During processing of green tea shoots to made tea a 30-40% loss of residue was observed. The transfer of residue from made tea to infusion was in the range 10-30% for both seasons, whereas 50-70% of the residues remained in the spent leaves. However, the degradation rate in both seasons followed first-order kinetics. The half-lives were in the range of 2-3 days for green shoots and made tea in both seasons.  相似文献   
59.
Microsystem Technologies - Design and fabrication of the through-glass via (TGV) based three-dimensional (3D) spiral inductors in the fused silica substrates by a simpler electrochemical discharge...  相似文献   
60.
In Underwater Acoustic Sensor Network (UASN), routing and propagation delay is affected in each node by various water column environmental factors such as temperature, salinity, depth, gases, divergent and rotational wind. High sound velocity increases the transmission rate of the packets and the high dissolved gases in the water increases the sound velocity. High dissolved gases and sound velocity environment in the water column provides high transmission rates among UASN nodes. In this paper, the Modified Mackenzie Sound equation calculates the sound velocity in each node for energy-efficient routing. Golden Ratio Optimization Method (GROM) and Gaussian Process Regression (GPR) predicts propagation delay of each node in UASN using temperature, salinity, depth, dissolved gases dataset. Dissolved gases, rotational and divergent winds, and stress plays a major problem in UASN, which increases propagation delay and energy consumption. Predicted values from GPR and GROM leads to node selection and Corona Virus Optimization Algorithm (CVOA) routing is performed on the selected nodes. The proposed GPR-CVOA and GROM-CVOA algorithm solves the problem of propagation delay and consumes less energy in nodes, based on appropriate tolerant delays in transmitting packets among nodes during high rotational and divergent winds. From simulation results, CVOA Algorithm performs better than traditional DF and LION algorithms.  相似文献   
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