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131.
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The treatment conditions for reducing the incidence of rot in stored citrus fruit with sodium o-phenylphenate (SOPP) foam and the possibility of improving the efficiency of the treatment were examined. Marked differences were noted among different packing houses with regard to ambient temperature temperature of the fruit surface, duration of treatment, SOPP content and pH of the solution, quantities of foam and of SOPP dispersed on the fruit, and between the o-phenylphenol (OPP) residues in fruit treated simultaneously. It should be possible to prolong the duration of treatment without increasing the OPP residues in the fruit above the tolerance limits of 10 ppm OPP in the whole fruit and without causing injury to the fruit.  相似文献   
133.
Citrus fruits were treated with wax coatings containing sodium 2-phenylphenate tetrahydrate (SOPP) and stored at 10 °C. No injuries appeared during 30 days' storage in Valencia oranges sprayed with waxes containing up to 4.75% of SOPP, or during 70 days' storage in Shamouti oranges and in grapefruit dipped in waxes containing up to 2.16% of SOPP. In Shamouti oranges and grapefruit dipped in waxes containing 3.1 to 3.88% of SOPP, injuries appeared at the beginning of storage. In non-injured fruits, the amounts of SOPP applied by waxing did not exceed 74.7 μg/cm2 of the fruit surface and the 2-phenylphenol (OPP) residues in the fruits did not exceed 36.8 parts/million; in injured fruits the amounts of SOPP applied varied between 105.1 and 211.3 μg/cm2 and the OPP residues between 41.5 and 123.6 parts/million. In non-injured fruit the amount of wax applied did not exceed 3.46 μl/cm2; in injured fruits the figure varied between 3.19 and 6.2 μg/cm2, suggesting that the wax coating concentrates at some places on the peel, causing injuries to the fruit. In injured grapefruit 7.93 μl/cm2 of wax was found on the injured part of the peel, and 3.21 μl/cm2 on the non-injured part, so that 124.6 μg of SOPP/cm2 corresponding to 61.6 parts/million of OPP in the fruit was applied to the fruit without causing injuries.  相似文献   
134.
Thirty-two 3-phenyl-1-monosubstituted(or 1, 1-disubstituted)prop-2-yn-1-ols, mostly with heterocyclic substituents, and four derivatives, were synthesised and tested in vivo against eight fungal plant pathogens of different taxonomic classes. No compound showed a wide spectrum of activity, however, nine of them were effective against Sphaerotheca fuliginea on Cucumis sativus, both in direct protectant tests and in systemic protectant tests by root application.  相似文献   
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The results of this study confirmed that dogs vaccinated subcutaneously with a commercially available multivalent vaccine containing modified-live canine distemper virus, canine adenovirus type 2, canine parvovirus type 2b, and canine parainfluenza virus antigens were protected against sequential experimental challenge 55 to 57 months after initial vaccination given at 7 to 8 weeks of age. All 10 vaccinates were protected against clinical diseases and mortality following parvovirus and infectious canine hepatitis experimental infections. All vaccinates were protected against mortality and 90% against clinical disease following distemper challenge. These data support at least a 4-year duration of immunity for these three "core" fractions in the combination vaccine.  相似文献   
138.
The embryonic vertebrate heart begins pumping blood long before the development of discernable chambers and valves. At these early stages, the heart tube has been described as a peristaltic pump. Recent advances in confocal laser scanning microscopy and four-dimensional visualization have warranted another look at early cardiac structure and function. We examined the movement of cells in the embryonic zebrafish heart tube and the flow of blood through the heart and obtained results that contradict peristalsis as a pumping mechanism in the embryonic heart. We propose a more likely explanation of early cardiac dynamics in which the pumping action results from suction due to elastic wave propagation in the heart tube.  相似文献   
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区域生态农业模式探讨--以天津市宝坻区为例   总被引:2,自引:0,他引:2  
卢安娜 《安徽农业科学》2006,34(2):343-343,345
探讨了区域生态农业模式的涵义、选择依据、类型;介绍了天津市宝坻区农业生态模式的创立与推广情况。  相似文献   
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