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61.
62.
Summary Wood storage has a great influence on the efficiency of a pulpmill. Great problems arise when using outside chip storage, especially in processing hardwoods, in that hardwood chips discolorate after a few days, which is not the case with spruce chips. The causes of such a different behavior of beech and spruce were investigated. It could be shown that a sufficient amount of active peroxidase, malate dehydrogenase and oxygen are prerequisites for the formation of phenoxy radicals within the beech lignin. This causes formation of new chromophores that discolorize the wood. Sufficient amounts of such enzymes are present in beech wood after harvesting. 相似文献
63.
Six‐week‐old seedlings of slash pine (Pinus elliottii) were inoculated with sporidia of Cronartium strobilinum, which is the cause of southern cone rust disease, by wounding the apical tips of the seedlings. Pycnial sori developed abundantly within 1 month of inoculation on the epicotyl and primary needles. The progress of the pathogen was confirmed histologically within the cells of the stem and haustoria were observed near the nucleus of the cells. In the needles, pycnial pustules developed and the fungus was abundant in the mesophyll. 相似文献
64.
介绍了原木蒸煮废水的处理方法,提出氧化塘法是小型木材加工厂处理该废水的最佳选择,并用实例简单介绍了氧化塘的设计选型问题. 相似文献
65.
Dipl.-Biol. H. -U. Schmidt 《Journal of pest science》1979,52(3):36-39
For testing the prompt and long-term effectiveness of a THURICIDE-dust containingBacillus thuringiensis var.kurstaki, serotype 3a, 3b with a viable spore count of 6 to 10 million per mg and an insecticidal activity of 3,2×103 international units (IU) per mg, the biopreparation was applied to rye on which larvae of the Indian Meal Moth (Plodia interpunctella Hbn.) were fed. A concentration of 20 mg (64×103 IU) of dust in 100 g of grain caused in 82% mortality, and a six-fold higher concentration (120 mg, 384 × 103 IU respectively) resulted in 99,0% mortality. The efficiency of the preparation was not reduced by storage for as long as 5 months in any five tests, which were at temperatures from 12°C to 28°C with 75% r.h. The larval stage of the surviving was prolonged by 3 to 4 weeks. Surviving moths, whose larvae were reared on grain to which the preparation was applied, were fertile and did not infest the following generation. 相似文献
66.
Wood Science and Technology - 相似文献
67.
68.
Packaging foils made of cellulose actetate, cellophane, polyethylene, polypropylene, polystyrene, polyester, polyvinyl chloride, attacked byRhizopertha dominica F.,Stegobium paniceum L.,Tribolium castaneum Hbst. and larvae ofPlodia interpunctella Hbn. were examined with the scanning electron microscope (SEM). Because of the destruction marks made by the insects, it is possible to determine with the SEM the side of packaging material which has been attacked by the pests. Due to the shape and position of the mouthparts of the insects the gnawing marks are rather typical for the different species. By means of a standard of comparison it might be possible to determine the family and perhaps the genus or species of the insects involved. The influence of shape and size of the mouthparts as well as the position of the mandibles in relation to the anatomy and to the axis of the body on the gnawing ability of stored-product pests is discussed. The reasons for the insect resistance of packaging materials are discussed (smoothness of the surface, rigidity, thickness). 相似文献
69.
70.
Zusammenfassung Es wird über das Auftreten von 25 Vorratsschädlingen, darunter 17 Käfer- und 3 Mottenarten, in den Lägern der Bevorratungsabteilung des Senators für Wirtschaft und Arbeit, der sonstigen Großlagerhaltung sowie in den Vorräten privater Haushalte berichtet. Die häufigsten Schädlinge in der Großlagerei waren Brotkäfer (Stegobium paniceum L.) und Speichermotten (Ephestia elutella Hbn.). Für den Vorratsschutz interessante Fälle und besondere Arten werden ausführlicher behandelt. Außerdem wird ein Überblick über die Entwesungs- und Entseuchungsarbeiten gegeben, bei denen neben den Begasungsmitteln mit den Wirkstoffen Methylbromid, Phosphorwasserstoff und Blausäure auch Vorratsschutzmittel auf der Grundlage von Dichlorvos, Pyrethrum und Piperonylbutoxid in verschiedenen Anteilen eingesetzt werden.
Mit einer Abbildung und 3 Tabellen 相似文献
Stored products protection activities of the Plant Protection Office Berlin. Pests of foodstuffs and pest-control in warehouses from 1980 to 1986
It is reported about the appearance of 25 stored-product pests, within 17 species of beetles and 2 species of moths in warehouses of the Bevorratungsabteilung des Senators für Wirtschaft und Arbeit as well as in the other warehouses and private households. The drugstore bettle (Stegobium paniceum L.) and the warehouse moth (Ephestia elutella Hbn.) were the most common pests. Cases of special interest and particular species are described in detail. Also is given a survey about the pest-controlling measures carried out with poisongas as methylbromide, phosphine and hydrocyanic acid and with insecticides on basis of dichlorvos, pyrethrum and piperonylbutoxide.
Mit einer Abbildung und 3 Tabellen 相似文献