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Influence of vegetable processing on pesticide residues in ready-to-eat vegetables studied at the experimental level does not necessarily reflect actual situation at household level. This study assessed influence of household vegetable processing practices on pesticide residues in ready-to-eat vegetables at household level in Arusha, Tanzania. Data on vegetable handling practices were collected through observations and physical interviews in 70 households. Samples of raw and ready-to-eat vegetables were collected from the households for pesticide residues analysis. Detectable pesticide levels were found in 46% of raw and 14% of ready-to-eat vegetable samples. Pesticide residues detected were in the groups of organophosphates (22.8%), pyrethroids (14.3%), organochlorines (7.14%), benzoic acids (7.14%), and carbamates (5.71%). Unauthorized pesticides (dichlorvos, tetramethrin, and bendiocarb) and environmentally persistent pesticide (dieldrin) were found at levels above their respective maximum residue levels. Washing of vegetables twice or more (p = .01) or peeling (p = .008) was significantly associated with reduction of pesticide residues. There was a significant association between occurrence of pesticide residues in ready-to-eat vegetables and washing of minor ingredients with the water used to wash major ingredients (p = .001). Household practices of washing of vegetables with portable water followed with peeling can reduce pesticide residue levels significantly. 相似文献
64.
In this paper a new Boolean equation for the orthogonalization of Boolean functions respectively of Ternary-Vector-Lists of disjunctive normal form is presented. It provides the mathematical solution of orthogonalization for the first time. The new equation is based on the new method of orthogonalizing difference-building ?. In contrast to other methods the new method has a faster computation time. Another advantage is the smaller number of product terms respectively of Ternary-Vectors in the orthogonalized result in contrast to other methods. Furthermore, the new equation can be used as a part in the calculation procedure of getting suitable test patterns for combinatorial circuits for verifying feasible logical faults. 相似文献
65.
Ashraf A. Kassim Eng Hong Tan Wei Siong Lee 《Circuits, Systems, and Signal Processing》2009,28(1):41-53
This paper introduces the 3D color set partitioning in hierarchical trees (3D-CSPIHT) low bit rate embedded video coding scheme.
The codec exploits the correlation between temporal and spatial wavelet coefficients and the interdependency between luminance
and chrominance components to code color video sequences without the need for explicit bit allocation. Besides offering rate
scalability, the new codec also produces multi-resolution scalable code streams. The hierarchical variable size block matching
motion estimation technique is also integrated to demonstrate the motion estimation option with 3D-CSPIHT. The coding results
show that 3D-CSPIHT produces better performance and visual quality compared to 3D-SPIHT. 相似文献
66.
Jayabrabu Ramakrishnan Muhammad Salman Shabbir Normalini Md Kassim Phong Thanh Nguyen Dinesh Mavaluru 《International Journal of Communication Systems》2020,33(7)
Internet of Things (IoT) as one of the last technology in the network domain is an environment of associated physical objects that are reachable through the Internet. Virtualization as the primary technology of IoT has a significant role in its popularization. The visualization strategies have a great impact on the IoT, but, as far as we know, there is not a comprehensive and systematic study in this field. Also, there is no systematic and complete way to discuss and analyze the related strategies. Henceforth, a systematic survey of virtualization techniques is presented in this paper. Different parameters based on the examination of the prevailing methods are considered in three main categorizations. Furthermore, the benefits and weaknesses connected with selected techniques have been discussed, and the significant issues of these techniques are addressed to improve the more efficient virtualization technique for the future. 相似文献
67.
This paper describes the implementation of the recently introducedcolor set partitioning in hierarchical tree (CSPIHT)-based scheme for video coding. The intra- and interframe coding performance of a CSPIHT-based video coder (CVC) is compared against that of the H.263 at bit rates lower than 64 kbit/s. The CVC performs comparably or better than the H.263 at lower bit rates, whereas the H.263 performs better than the CVC at higher bit rates. We identify areas that hamper the performance of the CVC and propose an improved scheme that yields better performance in image and video coding in low bit-rate environments. 相似文献
68.
Mahnaz M. Abdi Anuar Kassim H. N. M. Ekramul Mahmud Wan Mahmood Mat Yunus Zainal Abidin Talib Amir R. Sadrolhosseini 《Journal of Materials Science》2009,44(14):3682-3686
This work studies the electrical and optical properties of the conducting polymer composite films of polypyrrole–chitosan
(PPy–CHI). The surface plasmon resonance (SPR) technique was used to study the optical properties of PPy and PPy–CHI composite
films. Then, the values of the real and imaginary parts of the refractive indexes of PPy and PPy–CHI films were obtained by
nonlinear least square fitting using Fresnel equations for a three-layer system of SPR system. The electrical conductivity
measurements showed that the conductivity of the electrochemical prepared films improved in the presence of CHI and can be
controlled by varying the CHI amount in the composite. The thermal diffusivity of the PPy–CHI composite films was measured
by open photoacoustic spectroscopy and it has been shown that the thermal diffusivity is related to the electron migration
in the conjugation chain length. The increase in electromagnetic interference shielding effectiveness (EMI SE) with the increase
in electrical conductivity of the films is mostly from shielding by reflection rather than absorption. 相似文献
69.
70.
Formation of sorbitol by cathodic reduction of glucose 总被引:1,自引:0,他引:1
The steady-state formation of sorbitol by cathodic reduction of glucose was studied in a parallel-plate reactor of 200 cm2 electrode area. Earlier work was extended to explore the effect of flow rate, pH and current density. The effect of temperature between 20° and 47° C and the use of amalgamated lead as compared with chemical lead and other metals is discussed. It is shown that addition of Zn2+ ions accelerates the reaction and the reasons for this are discussed. The implications for industrial application are considered. 相似文献