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1.
Preparation of liquid polyols from d-(+)-glucose (Glc) and its derivative, methyl--d-glucoside (m-Glc), has been studied. Direct reaction of -caprolactone (CL) with Glc (CL:Glc = 2:1–5:1 in weight ratio) at 150°C using tin(II) 2-ethyl hexanoate (SnEht2) (series A), in which melted Glc was suspended in CL, resulted in a dark-brown coloration of the reactants. The reaction was accompanied by formation of high molecular weight resins, a pH drop, production of water, and a considerable decrease in the hydroxyl value from the theoretically expected one. In the case of Glc/ethylene glycol (EG)/CL reaction system with SnEht2 catalyst at 150°C (series B), in which the weight ratio of Glc to EG was fixed at 1:1, Glc dissolved in the EG/CL mixture, but the brown coloration of the reactant mixture still occurred. In this case, the formation of water was enhanced, but the other effects found in series A were suppressed to a considerable extent. In the m-Glc/CL/SnEht2 reaction system (series C), in which m-Glc reacted with two to five times weight amounts of CL under the same conditions adopted in series A, development of the color, the production of high molecular weight materials and water, and the changes in pH and hydroxyl value were not observed. These results are discussed based on the chemical structural differences: Glc exists mostly in the hemiacetal form, but tautomerizes to the aldehyde, whereas m-Glc is an acetal and is protected from reversion to the aldehyde.  相似文献   

2.
Sphingomonas paucimobilis SYK-6 produces unique and specific enzymes, such as-etherases,O-demethylases, and ring fission dioxygenases, for lignin degradation. Cleavage of arylglycerol--aryl ether linkage is the most important process in the lignin metabolic pathway ofS. paucimobilis SYK-6. We reported the genes (ligD, ligE, ligF) for enzymes that cleaved-aryl ether linkage of dimeric compounds in previous studies. In this study we synthesized the fluorescent high-molecular-weight lignin (UBE-DHP) by dehydrogenative polymerization. We investigated the-aryl ether cleavage ability of these enzymes produced in recombinantEscherichia coli. When UBE-DHP was incubated with LigF, 4-methylumbeliferone was released as a result of-aryl ether cleavage of O-methylumbelliferyl--hydroxypropiovanillone (compound III) incorporated in UBE-DHP. Here, we report that-etherase ofS. paucimobilis SYK-6 can be expressed inE. coli and is able to cleave the-aryl ether linkage in synthetic high-molecular-weight lignin.  相似文献   

3.
Aboveground and belowground root biomasses (Babove and Broot) were measured for young, isolated Rhizophorastylosa on Iriomote Island, Japan. The relationship between these two parameters was significant and given as the equation, Broot(g dry weight) = 0.394 × Babove(g dry weight) – 485 (r = 0.986). Multiple regression analyses also revealed good correlation between diameter and biomass of prop roots (Dprop and Bprop) and between prop root and root biomasses. Consequently, root biomass could be estimated from the measurements of diameter and biomass of prop roots using the multiple regression equation, Broot(g dry weight) = 80.0 ×Dprop(cm) + 0.86 ×Bprop (g dry weight) – 251. The relationship between DBH (diameter at breast height) and prop root biomass was also adequately described using an allometric equation.In Hinchinbrook Channel, Australia, redox potential (measured as Eh) and organic carbon stocks in the top 5cm of mangrove sediments were measured along a 600m transect from the frequently inundated, Rhizophora dominated zone on the creek edge, towards higher grounds, where Ceriops spp. became increasingly dominant. Eh values were about –60mV near the creek edge and increased to 260mV on higher grounds. Organic carbon stocks showed an opposite trend to Eh, with the values decreasing from about 360tCha–1 to 160tCha–1. At 18 sites, representing six different habitats, organic carbon stocks were also measured along with the DBH of mangrove trees. DBH was converted into aboveground biomass and then into root biomass using the equations obtained in the study on Iriomote Island. The average organic carbon stocks in the top 50 cm of sediments, aboveground biomass and root biomass were 296tCha–1, 123 tCha–1 and 52 tCha–1, respectively, and accounted for 64%, 25% and 11% of the total organic carbon stock.  相似文献   

4.
When (±)--oxo-guaiacylglycerol--(vanillic acid) ether (1) is degraded byFusarium solani M-13-1, the-ketone is initially reduced to giveerythro andthreo guaiacylglycerol--(vanillic acid) ethers (2), arylglycerol--aryl ethers, both of which are enantiomerically pure. The absolute configuration in each2 was determined by Mosher's method; the products were converted to,-di-(R)--methoxy--trifluoromethylphenylacetates (MTPA esters) (3) oferythro (-)- andthreo (+)-veratrylglycerol--(methyl vanillate) ethers (3), whose1H nuclear magnetic resonance (NMR) spectra were examined and compared with those of four di-(R)-MTPA ester (3) diastereomers from chemically synthesizederythro (±)-3 andthreo (±)-3. To assign the- and-MTPA-OCH3 peaks, the1H NMR scans of several compounds that have substructures of 3 and their 3,4,5-trimethoxyphenyl analogues were examined. When a racemic alcohol reacts with (R)-MTPA to give a pair of (R)-MTPA ester diastereomers, the value was defined as the absolute value of the difference in the1H chemical shifts of the peak between the diastereomers. It was found that the values of-MTPA-OCH3 were larger than those of-MTPA-OCH3 owing to a shielding effect of the veratryl ring located on the-MTPA-OCH3, and that the-MTPA-OCH3 peaks in the 3,4,5-trimethoxyphenyl compounds shifted downfield relative to those in the veratryl compounds. On the basis of the1h NMR data of (R)-MTPA esters, the absolute configuration of the four chemically prepared diastereomers (3) were determined. The catabolicerythro 3 [fromerythro (-)-3] andthreo 3 [fromthreo (+)-3] were identical to (R, S, R)-erythro 3 and (R, S, S)- threo 3, respectively. An hydrogen species in the fungal reduction would attack the-ketone fromre-face of both (R)-1 and (S)-1, givingerythro (S, R)-2 andthreo (S, S)-2, respectively.Part of this paper was presented at the 33rd Lignin Symposium, Tsukuba, November 1988  相似文献   

5.
Summary The Outbreak of Himera pennaria L. in 1962, in Lower Austria and Burgenland, and Causes of its break-down.The Hornbeam Measuring Worm,Himera pennaria L., hitherto described but once in forest-entomological literature as a bigscale forest pest, performed mass-attacks in 1962 in the Leitha hills (1500 acres) and Maria-Ellend wood, even clean-eating several hardwood species, especially hornbeam and also oak. The outbreak which occurred about mid-May broke perfectly down as soon as early June. The paper characterizes several bionomical and morphological data obtained during the course of the outbreak from individual development stages, also discussing the possible causes of the outbreak illustrated by climatograms. In conclusion, the biotical factors of the breakdown are treated, pointing out a virus disease (cytoplasmic polyhedrosis of mesenteron) as playing the greatest part. Along withH. pennaria L., alsoHibernia defoliaria L.,Hibernia aurantiaria Esp., andCheimatobia brumata L., as well as 4 species ofNoctuidae and 1 species ofArctiidae occurred rather frequently in the above-mentioned area, especially in the marginal zones of the Hornbeam Measuring Worm's mass-attack.
Résumé La gradation de l'Arpenteuse du Charme —Himera pennaria L. — en 1962, en Basse-Autriche et au Burgenland, et les causes de la débâcle de la calamité.L'Arpenteuse du Charme,Himera pennaria L., signalée une seule fois dans la litérature entomologique forestière comme ravageur en masse, s'est manifestée en dimensions calamiteuses en 1962, dans les montagnes du Leitha (600 ha) et au bois de Maria- Ellend, dépouillant — par endroits même de leur feullage eiitier — différentes espèces de bois feuillus, surtout des charmes mais aussi des chênes. La gradation qui s'était manifestée vers la mi-mai, subit une débacle complète dès le début de juin. Le mémoire présente quelques données bionomiques et morphologigues, obtenues au cours de la gradation, sur les différentes phases du développement, tout en discutant à l'aide de climatogrammes quelles pourraient être les causes de la gradation. En conclusion, on traite spécialement les facteurs biotiques de la débâcle, parmi lesquels une maladie à virus (polyédrose cytoplasmique du mésentère) a joué le premier rôle. Em même temps que l'Himera pennaria L., les insectes suivants ont été trouvés dans le territoire en question, le plus fréquemment dans les zones marginales de l'aire de grádation de l'Arpenteuse du Charme:Hibernia defoliaria L.,Hibernia aurantiaria Esp.,Cheimatobia brumata. L., 4 espèces de Noctuides et l espéce d'Arcttides.
Himera pennaria L. 1962 . . . . ,Himera pennaria L., -- , 1962 . (600 .) , , . , , . , , , . , ( ). H. Pennaria L. Hiberia defoliaria L., Hibernia aurantiaria Esp., Cheimatobia brumata L., 4 Noctuidade 1 Arctiidae, .

Herrn Prof. Dr. A. Acatay zum 60. Geburtstag gewidmet.

Die Untersuchungen erfolgten in Zusammenarbeit mit der Landesforstinspektion für Niederösterreich, speziell mit der Bezirksforstinspektion Wien-Umgebung und der Landesforstinspektion für das Burgenland, wofür an dieser Stelle herzlichst gedankt sei.

Für Herstellung der mikroskopischen Präparate sei Frl. H. Meldt, für die Freilandaufnahmen und mikroskopischen Aufnahmen Herrn N. Maisner bzw. Herrn O. Baschny der Forstlichen Bundesversuchsanstalt Mariabrunn, für die Aufnahmen der elektronen-mikroskopischen Präparate Herrn Hayek vom Physikalisch-chemischen Institut der Universität Innsbruck gedankt.  相似文献   

6.
The deformation behavior of low molecular weight phenol formaldehyde (PF) resin-impregnated wood under compression in the radial direction was investigated for obtaining high-strength wood at low pressing pressures. Flat-sawn grain Japanese cedar (Cryptomeria japonica) blocks with a density of 0.34g/cm3 were treated with aqueous solution of 20% low molecular weight PF resin resulting in weight gain of 60.8%. Oven-dried specimens were compressed using hot plates fixed to a testing machine. The temperature was 150°C and the pressing speed was 5mm/min. The impregnation of PF resin caused significant softening of the cell walls resulting in collapse at low pressures. The cell wall collapse was strain-dependent and occurred at a strain of 0.05–0.06mm/mm regardless of whether the wood was treated with PF resin. Thus, pressure holding causing creep deformation of the cell walls was also effective in initiating cell wall collapse at low pressure. Utilizing a combination of low molecular weight PF resin impregnation and pressure holding at 2MPa resulted in a density increase of PF resin-treated wood from 0.45 to 1.1g/cm3. At the same time, the Youngs modulus and bending strength increased from 10GPa to 22GPa and 80MPa to 250MPa, respectively. It can be concluded that effective utilization of the collapse region of the cell wall is a desirable method for obtaining high-strength PF resin-impregnated wood at low pressing pressures.  相似文献   

7.
Zusammenfassung 1. Die Intensität der Harzausscheidung ist kein sicheres Kriterium bei der vergleichenden Diagnose der Widerstandsfähigkeit verschiedener Kiefern-Arten gegen Schadinsekten. In dem Widerstandsmechanismus der Kiefer spielt nicht die Quantität des Harzes, sondern die Qualität eine Rolle und unbedingt seine biologische Aktivität.2. Kiefeinharz ist ein natürliches Schutzmittel des Baumes gegen. Insektenschäden. Verschiedene Kiefern-Arten enthalten Harz von qualitativ verschiedener biologischer Aktivität für Insekten. Das bezieht sich auch auf das Harz ein- und derselben Kiefernart bei unterschiedlichem physiologischen Zustand. Das Harz der geschwächten Kiefernbäume verliert seine Schutzeigenschaften und sein Geruch wirkt auf Insekten als ein Zeichen der Eignung des Baumes für ihre Ernährung und Entwicklung.3. Die biologische Aktivität des Harzes ist durch die in ihm vorhandenen ätherischen Öle, die auis Terpenoiden bestehen, bestimmt. Die Terpenoide besitzen für die Insekten verschiedene biologische Aktivitä t, welche von ihrer Menge, ihren Eigenschaften, den Beziehungen der Komponenten untereinander und optischen Isomeren abhängen, die insgesamt ihre Qualität als natürliche Schutzstoffe des Nadelbaumes bestimmen und den Widerstand gegen Insektenschäden in bestimmtem Maße bewirken.
1. . , , .2. . . , . , .3. , . , , , , , .
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8.
Twelve-week-old container-grown seedlings of noble fir (Abies procera Rehd.) and Shasta red fir (A. magnifica A. Murr. var. shastensis Lemm.), both high-elevation species, were grown under controlled environments in a study of induction of terminal-bud dormancy. Eight treatment combinations of long (15 h) or short (11 h) photoperiods, warm (25°/20°C) or cool (18°/12°C) thermoperiods, and dry (–1.2 MPa) or wet (–0.6 MPa) moisture regimes were imposed upon seedlings for 12 weeks. Treatment factors significantly affecting the induction of dormancy in terminal buds of seedlings were identified over time. The results suggest that seedlings responded dynamically to dormancy cues. The warm/dry and cool/wet combinations induced dormancy in the first 2 weeks in noble fir and in the first week in Shasta red fir. Short-day/warm and long-day/cool combinations enhanced dormancy induction in weeks 3 to 4 in noble fir and in weeks 1 to 7 in Shasta red fir. Short days and cool thermoperiods independently hastened dormancy induction in noble fir in weeks 5 through 12.  相似文献   

9.
Rhizophora mangle L. dominated 10 overwash islands within Tampa Bay forming the northernmost mangrove forests on the west coast of Florida. The mean number of trees and basal area were 5040 trees ha-1 and 20.5m2ha-1, respectively. Basal areas ranged from 1.1 (Avicennia germinans (L.) Stern), to 2.6m2ha-1 (Laguncularia racemosa Gaertner), to 16.8 (R. mangle). Cockroach Bay mangroves are small (5.8–7.0m tall) versus coastal forests of south Florida and the Caribbean. Total litter production for a 12 month period was maximal in September for fringing (7.4gdwtm-2d-1) and interior (8.7gdwtm-2d-1) areas with the two zones not being significantly different. Average litter fall (3.1gdwtm-2d-1) was similar to more tropical Caribbean mangals. Leaves accounted for 68 of the litter and reproductive material for 6, being similar to tropical riverine and overwash marine angiosperm communities on the Mexican coast. Although mangrove forests in Tampa Bay are small in stature and experience cold damage and occasional frosts, their litter fall is similar in biomass to that of more tropical mangals. However, their reproductive output is low based on litter fall versus more tropical mangals suggesting that the northern extension is less than optimum. Macroalgal diversity was low (10 species) as compared to Caribbean mangals. Macroalgal turf (0.8gCm-2d-1) and epiphyte communities of A.germinans pneumatophores (2.7gCm-2d-1) have productivity levels that are equal to or greater than those of Caribbean mangals.  相似文献   

10.
Zusammenfassung Es wurden in Kiefernkulturen Untersuchungen über die Tagesdynamik des Harzdruckes und der Intensität der Harzabsonderung geführt und die Ergebnisse in Beziehung zum Befallsgrad des KiefernknospentriebwicklersRhyacionia buoliana Schiff. gesetzt.Im Verlauf eines Tages variierte der Harzdruck wenig, die Intensität der Harzabsonderung dagegen stark. Die höchste Harzfluß-Intensität fällt in den Zeitraum zwischen 13 und 16 Uhr. Die Flugzeit des Wicklers, nach 18 Uhr, liegt somit außerhalb der Zeit des stärksten Harzflusses.Weder der Index der Harzfluß-Intensität noch jener des Harzdruckes zeigten eine Beziehung zur Stärke des Wicklerbefalls. Sie sind daher als Kriterien der Widerstandsfähigkeit einer Kulturkiefer gegenRh. buoliana, zumindest unter den Verhältnissen der Süd-Ukraine, nicht verwendbar.
Summary Studies on the diurnal rhythm of resin pressure and resin secretion in connection with the degree of pine-infestation byRhyacionia buoliana Schiff.In the course of one day pines in the age of 15 years showed only a small variation in resin pressure but a great one in secretion of resin. The maximal intensity of secretion was observed early in the afternoon. The moths ofRh. buoliana are flying after this time when the secretion of resin is low.There was no connection between resin pressure and secretion of resin on the one hand and the degree of pine-infestation byRh. buoliana on the other. The two factors are not suitable for indicating the degree of pine-infestation by this tortricid.
- . / 0 26 / /., , . , 13 15 . , , , , .
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11.
Sodium, potassium, magnesium, calcium and physicochemical parameters were monitored for one year in a mangrove tidal creek near Bragança, North Brazil, to determine their tidally induced and seasonal variations and the main parameters controlling the concentration of these cations. On a daily basis, cation concentrations showed a strong tidal rhythm due to the mixing of estuarine and mangrove waters. Mean concentrations were highest at the end of the dry season (December 1996) and lowest (April 1997) towards the end of the rainy season. Average values over one year were: Na+ = 329± 118mM, K+ = 6.9±2.5mM, Mg++=37 ±14 mM and Ca++= 6.9±2.4mM. Dissolved oxygen concentration was higher during the dry season due to enhanced aquatic primary production, with a maximum daily average value of 8.5mg/L in July 1996, and a minimum value of 4mg/L in June 1997. Cation concentrations were transformed relating them to the respective average values in standard seawater at salinity 35. Although cation concentrations and salinity tightly correlated, this standardization showed that the concentrations of K+, Ca++ and Mg++ did not depend solely on salinity and reflected the seasonal variation in aquatic primary production. It also allowed the discrimination of their sources (marine, riverine and groundwater). Thermodynamic equilibrium calculations indicate that phytoplankton may be regulating the concentration of these cations in the water column indirectly by inducing precipitation through pH increase and directly through metabolic uptake.  相似文献   

12.
Zusammenfassung In Freiland- und Laborversuchen wurde die Wirkung des Pflanzenschutzmittels Sevin auf Regenwürmer untersucht. Dieser Stoff ist in Pulverform und als Suspension für diese Organismen außerordentlich gefährlich. Schon der Kontakt mit sehr geringen Mengen bewirkt schwere Lähmungserscheinungen und irreversible histopathologische Schäden.
Summary Experiments in the field as well as in the laboratory showed up the effect of the pesticide Sevin on rainworms. In the form of powder as well as a suspension this material is extremely toxic for them. Contact with smallest quantities even causes severe paralysis and irreversible histopathologic damages.
Résumé Aussi bien dans la nature que au laboratoire nous avons étudié l'activité de l'insecticide Sevin sur les vers de terre. Ce produit est en poudre ou en suspension extrémement dangereux pour ces organismes. Le seul contact avec des quantités minimes de ce produit provoquent des phénomènes de paralysie et des troubles histopathologiques irreversibles.
SEVIN . . .
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13.
Summary This paper studies the influence of the used creep function, and the duration of the experimental sustained loading from which the creep function was derived, in modelling the long-term buckling strength of timber columns. The sensitivity of this buckling strength to creep and initial deflection is numerically studied using an energy approach that takes into account the initial deflection. Various creep functions — power laws as well as exponential laws — derived from bending experiments of different durations are used for the numerical simulation. The crucial need for experimental results issued from very long load period experiments is identified. Such experiments may lead to a more credible creep analysis of timber structures.Symbols i radius of giration - s stress level - EL effective MOE - E0 instantaneous MOE - I inertia moment - K,K geometrical matrices - L length of beam or column - Lf effective length - Ncr axial force, buckling load - U elastic strain energy - W external forces work - t time variable - u moisture content (m.c.) - v total deflection - vc, ve, v0 creep, instantaneous elastic and initial deflections respectively Greek Letters (t) time function - , e, 0 total, instantaneous and initial strains respectively - twist rotation - (t) creep coefficient or fractional creep or relative creep - (x) shape function - load factor - longitudinal shortening - total potential energy - creep factor - relaxation time  相似文献   

14.
Zusammenfassung Die Altlarven 2. Generation der AmpferblattwespeAmetastegia glabrata Fall. sind im Obstbau als Schädling bekannt. Die Schäden entstehen bei dem Versuch der Larven, in Früchten Puppenkammern anzulegen.Üblicherweise verpuppen sich die Larven in den trockenen Stengeln der Nährpflanzen(Polygonaceae) oder anderem trockenem oder verholzten Pflanzenmaterial.Es wird über einen gesicherten Fall berichtet, in demAmetastegia glabrata-Larven in verarbeitetem Nutzholz (Plakattafel) schädlich geworden sind. Ein weiterer Fall konnte nicht völlig geklärt werden; jedoch waren auch hier Blaltwespen-Larven in einer Wohnung in verarbeitetes Nutzholz (Türrahmen) eingedrungen.Nach dem geringen Umfang der Schäden, die nur durch die Anlage kurzer Puppenkammern in weichen Holzteilen entstehen, istAmetastegia glabrata in die Gruppe der gelegentlichen Holzzerstörer einzureihen. Allerdings kann durch diese Art völlig gesundes Holz im Freiland angegriffen werden.Holzschutzsalze vom U-Typ genügen zur Vorbeugung nicht. Vorbeugungs- und Bekämpfungsmaßnahmen werden besprochen.
Summary Attack on wood by larvae of the dock sawfly Ametastegia glabiata Fall. (Hym., Tenthiedinidae) Normally the mature larvae of the last brood of the dock sawfly bore themselves for pupation into dry stems of plants.By the gnawing efforts in certain years of appearance in masses, however, they may attack fruit too, especially apples, and cause considerable damage by numerous gnawing spots.Besides these known injuries on fruitA. glabrata has now been stated in two cases as an occasionally dangerous animal to dry timber too.The damage caused is described by word and picture; preventive and curative measures are discussed.
Résumé Attaque du bois par des larves de la Tenthrenidé Ametastegia glabrata Fall. (Hym., Tenthredinidae) Normalment les larves adultes de l'A. glabrata se forent dans les tiges sèches des plantes pour la mé tamorphose.Cependant aussi des fruits, surtout des pommes, sont attaqués par le ronger pendant les anées quand ces insectes paraîssent en masse. Des dommages considérables sont provoqués aux points d'attaque nombreux.A côté de ces dommages connus aux fruits l'A. glabrata a été constaté en deux cas comme causeur de dommage par occasion en bois sec de construction.Les dommages sont décrits et figurés; des methodes preventives et curatives sont discutées.
? Ametastegia glabrata Fall. (Hym., Tenthredinidae) . , , , . Ametastegia glabrata Fall. ( ) . , .

Mitteilung aus dem Holzschutzlaboratorium der Farbenfabriken Bayer AG., Werb Uerdingen  相似文献   

15.
Zusammenfassung Während mehrer r Monate wurden Weibchen vonBoophthora erythrocephala undWilhelmia lineata am Kaninchenohr gefüttert und die Überlebensrate während der Eireifungsphase,
Nutrition and Reproduction in Palaearctic Blackflies (Simuliidae: Diptera). I. Bloodfeeding ofBoophthora erythrocephala De Geer andWilhelmia lineata Meigen on RabbitsFemales of the mammalophilic species,Boophthora erythrocephala andWilhelmia lineata, feed on cattle and horses in the field. When fed on the rabbit's ear under laboratory conditions, they differ considerably in bloodsucking activity, in mortality during digestion of blood, natality, and hatching rates of first instar larvae. InB. erythrocephala 641 wild-caught- fed in 74,1% without seasonal variation. When females were kept up to four days before feeding their bloodsucking activity did not decrease. Laboratory-emerged- usually fed in even higher rates (416/533) and 4–6 days old flies fed more frequently than younger or older females. Survival rates during digestion of blood in 4 days were 60% in wild-caught, 40% in laboratory-emerged-, and 74% in cattle-fed-. Only 29% of wild-caught and the cattle-fed- but 50% of the laboratory-emerged flies could be induced to lay eggs on wet substrate. Natality of cattle- (219 eggs/) and laboratory-emerged fed on the rabbit (225 eggs/) were significantly higher than in wild-caught rabbit-fed- (191 eggs/). The number of eggs developing to first instar larvae generally was low (42%). InW. lineata wild-caught- fed less successfully (162/407) and showed considerable seasonal variation. The best results were obtained in September and October. Keeping them in the laboratory for 1–4 days reduced the bloodsucking activity. In laboratory-emerged- the best feeding result (347/724) were obtained with 4–6 day old flies but their survival during maturation of eggs remained low (55%). It was higher with wild-caught (67%) and cattle-fed- (78%). In all cases 60% of them could be induced to oviposit. The rabbit-fed wildcaught or laboratory-emerged flies produced significantly more eggs (183 resp. 197 eggs/) than cattle-fed ones (138 eggs/). Most egg batches contained only 16% fertilized eggs. In laboratory-emerged- ofB. erythrocephala andW. lineata the potential natality was highest in spring, lowest in summer and increased again in autumn. The number of eggs/ was affected by the blood volume. Starting with laboratory-emerged flies fed on the rabbit a production factor of 10.9 is calculated forB. erythrocephala and of 5.4 forW. lineata rearing from the imago to the first instar larva. When the larvae are reated to adults with 44% efficiency a reproduction of 2.4 resp. 1.2 per generation of females results.

Mit 4 Abbildungen und 4 Tabellen  相似文献   

16.
Wood plastic plywood (WPPW), composed of veneer and styrofoam, was manufactured without special adhesives such as urea–formaldehyde or phenol–formaldehyde resins, and its vibrational properties were investigated. WPPW can be produced at 1MPa and 160°C for 9min (three-ply) and 12min (five-ply). The dynamic Youngs modulus reached its highest value when the styrofoam thickness was 30mm. The sound velocity and dynamic Youngs modulus had minimum values at a grain angle of 45°. The results for dynamic Youngs moduli measured by a longitudinal vibration method and an in-plane flexural vibration method were almost the same. Dynamic shear moduli were measured by an in-plane surface wave propagation test and an in-plane flexural vibration method. From the experimental results, the dynamic shear moduli at 0° and 90° by the two methods were relatively close, although the surface wave propagation test results were higher than those from the flexural vibration method. Dynamic shear moduli at a grain angle of 45° measured by the in-plane surface wave propagation test and calculated from theory were relatively close. The surface wave propagation test results were smaller than the results calculated from theory. The shear stress distribution factors were about 1.000–1.189 for WPPW.  相似文献   

17.
Summary For protection of agricultural crops, archards, forests and stored products a system of institutes for vegetative protection have been gradually built in Bulgaria within the last fifteen years. Now a leading part in the study of pests and diseases of plants are taking the Academy of Rural Economy Sciences and the Institutes for Plant Protection, for Forest Protection, the Zoological Institute by the Bulgarian Academy of Science, the Higher Rural Economy Institute and the Higher Forest Institute. Specialists of all ranks are working at these institutes: academicians, member correspondents, professors, senior and junior scientific collaborators and a great number of experts and assistants. Parallel with the studies of specific composition of pestilent insects, their biology is being explored and experiments are being made with insecticides. An inquiry is also being undertaken for utilization biologic combat against noxious insects. In aid of scientific institutes a dense network of services for heading the research work and combat on the terrain has been organized.
Résumé Pour la défense des cultures agricoles, des vergers, des forêts et des produits récoltés, un système d'instituts pour la défense végétale a été successivement dé veloppé en Bulgarie pendant les dernières quinze années. Actuellement l'Academie des sciences de l'economie rurale et les Instituts pour la défense végétale ont le rôle dirigeant dans les recherches de la nocivité et des maladies sur les plantes. Dans ces instituts travaillent des spécialistes de toutes les catégories scientifiques: des académiciens, des membres-correspondants, des professeurs, des travailleurs scientifiques supérieurs et plus jeunes, avec un grand nombre d'aides-spécialistes. Parallèllement à l'étude de composition specifique des insectes nuisibles on étudie sa biologie, de même on fait des expériences avec des insecticides. Aussi on cherche à utiliser la lutte biologique contre les insectes nuisibles. Pour faciliter les instituts scientifiques dans cette lutte et leur recherche sur le terrain, un immense service est organisé dans tous les plus grands emplacements peuplés du pays.
. , 15 , , , . . - , , , . - , , - . : , , , . , . . , . - , . .
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18.
Zusammenfassung In dem für die Besonderheiten der Kiefernrindenwanze konstruierten Olfaktometer, wurden die Chemotaxie des Schädlings auf die Terpenoide aus ätherischen Ölen der Gemeinen Kiefer untersucht. Es wurden dabei Terpenoide mit vorwiegend anlockender und abschreckender Wirkung isoliert. Einige Terpenoide (-Pinen und Limonen) verwandeln bei einer Änderung ihrer Konzentration ihre anlockenden Eigenschaften in abschreckende. Bei der Verdampfung von der Oberfläche der pflanzlichen Gewebe der Kiefer bilden die Terpenoide eine Schutzwolke — ein äußeres Schutzsystem (R-System). Bei Überwiegen der anlockenden Stoffe wird in den Dä mpfen der wirksamen Stoffe das System lockend (A-System). Es wurde ein Modell des äußeren Systems aufgebaut und ihre ungefähre mathematische Erklärung gebracht, die erlaubt, die Anlockung der pflanzlichen Gewebe der Kiefer für die Rindenwanze nach den Ergebnissen der chromatographischen Analyse der atherischen Öle zu ermitteln. Das äußere Schutzsystem der Kiefer ist eines von den Systemkomplexen, welches als Schutzfunktion die Widerstandfähigkeit der Kiefer gegen Schadinsekten erfüllt und gewährleistet.
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19.
Zusammenfassung Die Befallsstärke von Erdbeerpflanzen durch Blattälchen wird allgemein in Älchen je 20 g Herzen ausgedrückt. Man versteht unter dem Herz einer Erdbeerpflanze die Knospe, die jungen Blütenanlagen und die unentfalteten Blätter. Es besteht aber ein gewisser Ermessensspielraum in der Zuordnung zu gefaltet bis zu voll entfaltet. Meist ist die Knospe am dichtesten befallen. Der Durchschnittsbefall sinkt deshalb um so tiefer, je mehr nicht zur Knospe gehörende Pflanzenteile mituntersucht werden. Es handelt sich um die Frischgewichte der Herzen. Diese unterliegen Schwankungen je nach Jahreszeit, Erdbeersorte und Witterung. Ferner sind die Herzen stark befallener Pflanzen leichter als die gesunder Pflanzen. Im Durchschnitt wiegen im Frühjahr 30 Herzen 20 g. Es wird vorgeschlagen, die veränderliche Bezugsgröße 20 g Herzen durch das konstante Maß 30 Pflanzen oder 30 Rosetten zu ersetzen.
Summary On the isolation of bud and leaf nematodes (Aphelenchoides fragariae andA. ritzemabosi) from strawberry and chrysanthemum. Part II.The degree of infestation to strawberry plants by the leaf and bud nematodes is usualy expressed in nematodes per 20 g hearts. The heart of a strawberry plant includes the bud, the young inflorescences and the young closed leaves. A certain degree of judgement is requirred to distinguish between a closed leaf and an opened one. As the nematodes are usualy most concentrated in the bud, the degree of infestation is brought down by the inclusion of parts of the plant that do not directly belong to the bud.The weight of the hearts is also natably affected by weather conditions, season and plant variety. Furthermore heavily infested hearts are lighter than healthy ones. In spring, 30 hearts weigh approximately 20 g. It is suggested that the unstable measure of 20g hearts be substituted by the more reliable amount 30 plants or 30 rosettes.
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20.
Zusammenfassung Im Jahre 1963 wurde in verschiedenen Gebieten Deutschlands ein Massenauftreten des BuchenspringgrüßlersRhynchaenus (Orchestes) fagi L. beobachtet. Die Jungkäfer gingen ab Mitte Juni an Obst über und verursachten dort große Schäden. Bevorzugt wurden Aprikosen, Süßkirschen und Äpfel der Sorten Cox Orange, Golden Delicious und Goldparmäne, wä hrend Ontario nicht befallen war.In Rheinland-Pfalz wurden noch Ende Oktober agile und lebhaft fressende Käfer in großen Massen selbst an lagerndem Obst beobachtet.Im Frühjahr 1964 wurden in Rheinland-Pfalz erneut Massen von Altkäfern in Buchenbeständen beobachtet. Die Jungkäfer schädigten außer Obst auch Beta-Rüben.In künstlichen Zuchten konnten lediglich 8 von Hundert der Versuchstiere überwintert werden.Zur Bekämpfung erwiesen sich Kontaktinsektizide auf Lindan-DDT-Basis den Phosphor-Estern überlegen.
Summary In 1963 an enormous appearance ofRhynchaenus (Orchestes) fagi L. was observed in many parts of Germany.The young beetles attacked fruits in the second part of June. Apricots, cherries and especially the apple varieties Cox Orange, Golden Delicious and Goldparmaine were most severe damaged. Only the variety Ontario remained unattacked.Observations in Rhineland-Palatinate proved thatRh. fagi attacked apples still in October even at store houses.During the spring 1964Rh. fagi attacked beech-trees and fruits once more and even beets.Kept in special assays only 8 percent of the caged beetles survived the winter.In experiments for controllingRh. fagi proved more susceptible to Lindane-DDT and less susceptible to parathion and diazinon.

Meinem verehrten Lehrer, Herrn Professor Dr. Hans von Lengerken zum 75. Geburtstag gewidmet.  相似文献   

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