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1.
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 . . .
  相似文献   

2.
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   

3.
We prepared carpet cleaners containing three wood oils extracted from Thujopsis dolabrata Sieb. et Zucc. var. hondai Makino, Chamaecyparis obtusa Endl., and Chamaecyparis taiwanensis Masamune et Suzuki and studied their effects on mites and perfumerists' impressions. The oil concentrations were set at 0.1%, 0.2%, 0.4%, 0.8%, and 1.6%. The effects on Dermatophagoides pteronyssinus Trouessart were investigated. The sensory evaluations were conducted by seven male perfumerists using the SD method and they were asked to describe freely their impressions of the scents. These results showed that: (1) all three types of wood oil had a significant effect on making D. pteronyssinus inactive at 0.1% concentration; and (2) the wood oil of T. dolabrata evoked refreshing, natural, rich, and intellectual feelings; C. obtusa oil evoked vivacious, rich, and intellectual feelings; and C. taiwanensis evoked refreshing, natural, rich, rough, masculine feelings. According to the test subjects, T. dolabrata evoked woody and earthy impressions; C. obtusa evoked woody, citrus, and pine-resin impressions; and C. taiwanensis evoked woody, citrus, and medical impressions. Many issues remain to be investigated, but the inclusion of wood oil in carpet cleaners offered both good mite control and a pleasant aroma to humans. This study suggests a new potential for using these wood oils.  相似文献   

4.
Previous papers have quantitatively indicated that the total movement of cement bonded particleboard (CBPB) is equal to the sum of the movement of its components. This paper examined the efficacy of the law of mixtures when applied to the movement of a wood-cement composite under internal swelling or shrinkage stresses. Abundant data generated in companion papers were first manipulated to develop the universal formulae for predicting the movement of components. In conjunction with previous numerical results from image analysis of the structure of CBPB, and the orientated elasticity and stress algorithms, the models for theoretically predicting mass and dimensional changes of CBPB were derived. Validation studies were conducted and these demonstrated an excellent agreement of the theoretical predictions with experimental data for both mass and dimensional changes of CBPB due to internal swelling or shrinkage stresses during adsorption and desorption. The success also implied that CBPB can be treated as a composite and its properties can be well derived by the law of mixtures even though CBPB is an unusual type of composite having a very high volume fraction of wood chips, but a very high mass fraction of cement paste.Notation ERT Mean transverse modulus of elasticity of wood - EL Longitudinal modulus of elasticity of wood - Ep Modulus of elasticity of cement paste - Ewa Modulus of elasticity of embedded wood chips at angle - E Modulus of elasticity of wood chips at direction - E Modulus of elasticity of wood chips at direction - GLRT Mean transverse shear modulus of wood - L(T)cp Length/width (thickness) change of CBPB at angle - L(T)p Length (thickness) change of cement paste - mpf Mass fraction of cement paste in unit mass of CBPB - mwf Mass fraction of wood chips in unit mass of CBPB - Mcpj Mass change of CBPB at the various conditions tested - Mpj Mass change of cement paste at corresponding conditions - Mwj Mass change of wood chips at corresponding conditions - M(L; T)w/P Mass, length or thickness changes of wood chips or cement paste at various conditions - t Duration of exposure - LRT Mean transverse Poissons ratio of wood - Vpf Volume fraction of cement paste in unit mass of CBPB - Vwf Volume fraction of wood chip in unit mass of CBPB - cp Density of CBPB - k Density of wood chip or cement paste - cp Overall stresses of CBPB at angle - L Stress in the longitudinal direction of wood - RT Mean stress in the transverse direction of wood - p Stress of cement paste - w Stress of the wood chips at angle - Stress of the wood chips at direction - Stress of the chip at direction - cp Strain in CBPB - p Strain of cement paste - WL Strain in the length of wood chips - WT Strain in the thickness of wood chips - w Strain in wood chips - Angle between the longitudinal direction of wood chips and surfaces or edges of CBPB - Angle between wood chips and edges (length direction) of CBPB - Angle between wood chip and vertical coordinate - A, B, C Coefficients related to the feature of materials and exposure conditions The senior author wishes to thank Professor W.B. Banks of University of Wales, Bangor for his constructive discussions and assistance and the British Council for partly financial support.  相似文献   

5.
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   

6.
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.
, , .- , . /-, / . , , , /R- /, /A-/. , . .
  相似文献   

7.
Summary In this paper a new method for rearingTribolium destructor is described. For oviposition the imagines are cultured in a thermostate (27° C, 70% RH) on a mixture of flour and yeast; additional feeding of pieces of fresh apple is necessary. The sifted eggs also must be stored in the thermostate. The newly hatched larvae must be isolated from the mixture of egg shells, particles of yeast, excrements of the beetles and of the remains of flour, and they get fresh food (flour-yeast-mixture). The rearing is performed in the thermostate in glass-vessels of a bigness corresponding to the developmental state of the larvae. Fully grown larvae must be isolated (for getting exactly dated material of pupae) or they are put in Petri-dishes furnished with fluted coardboard. Pupae and imagines which are not used for obtaining eggs are cultured at room temperature in darkness (flour-yeast-mixture with additional feeding of apple pieces).
Résumé Dans ce travail une nouvelle méthode de l'élevage deTribolium destructor est décrite. Pour la déposition des oeufs les adultes sont tenus dans un thermostat à température constante (27° C et 70% RH) dans une mixture de farine et de levure; en outre il faut un don supplémentaire de pomme fraî che. Les oeufs séparés en criblant sont aussi tenus dans le thermostat. Les larves qui viennent d'é clore sont à séparer de la mixture des coques d'oeuf, des particules de levure, des excréments et des restes de farine, et après elles reçoivent de la nourriture fraîche (mixture de farine et de levure). L'élevage a lieu dans des bocaux dans le thermostat. La grandeure de ces bocaux doit correspondre à l'état du développement des larves. Les larves complétement développées sont à isoler (pour obtenir du materiel des chrysalides bien datées) ou à mettre dans des bocaux »Petri« fournis de carton ondulé. Les chrysalides et les adultes, qui ne sont pas nécessaires pour la déposition des oeufs, sont á tenir à témperature de chambre dans l'obscurité (mixture de farine et de levure, de temps en temps aussi de pomme).

» «Tribolium destructor Uyttenb.). 27° C 70% PH ; . . , , ; ( ). , . ( « »-, ). , ( — , ).


Diese Untersuchung wurde im Zusammenhang mit einem größeren Forschungsvorhaben durchgeführt, das durch Unterstützung der Deutschen Forschungsgemeinschaft ermöglicht wird.  相似文献   

8.
Summary Characteristic features of wood deformation under loading at changing moisture contents (temperature) are discussed on the basis of results from rheological tests with hardwood. General laws of deformation in wood as a result of various cyclic effects of loading as well as of temperature and moisture content have been established. These laws have been used to solve the problem of the plane stress state in lumber when dried by using the method of finite elements. To control internal stresses and for an effective drying process, it is suggested that differential shrinkage should be measured, i.e. the difference between the displacements of points on Both verges of the board's edge and in the centre of the edge.Presented at the Meeting of the European-African Group of IAWS with the topic Structure and Utilization of hardwoods, Banska Bystrica, CSSR, September 9–11, 1975.  相似文献   

9.
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   

10.
Summary The reaction of ferric chloride with the lignin model guaiacol affords primarily a complex mixture of coupled guaiacol oligomers. Major components were the symmetrical carbon-carbon coupled dimer 3,3-dimethoxy-[1,1-biphenyl]-4,4diol and the trimer 3,3,5-trimethoxy-[1,1:3,1-terphenyl]-4,4,4-triol which were isolated by preparative HPLC and characterized by 1HNMR spectroscopy and mass spectrometry. An unstable component believed to be a 4,4-diphenoquinone derived from the trimer was also prominent. The reaction of chromium trioxide with guaiacol yields the same dimer, trimer and diphenoquinone as well as 2-methoxy-p-benzoquinone. The major product with chromium trioxide, however, is an inert, highly insoluble polymer which was shown by degradation to contain guaiacol oligomers bound or crosslinked by hydroxylated chromium species. Magnetic susceptibility measurements clearly indicated that the valency of chromium in the polymer was + 3. It is postulated that similar complexes formed from phenolic lignin units are responsible for the weather resistance of chromium trioxide treated wood surfaces. In a broader context this study is relevant to the fixation of hexavalent chromium from a range of widely used wood preservative formulations.The authors wish to thank the following: Tom Syers (CSIRO Division of Forest Products) for technical assistance, Mary Reilly (CSIRO Division of Forest Products) for NMR spectral determinations and Ivan Vit (CSIRO Division of Chemicals and Polymers) for mass spectral determinations  相似文献   

11.
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 CharmeHimera 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   

12.
Summary That the behavior of wood in service results from its structure is generally accepted by wood scientists. No doubt this acceptance is due to the broad interpretation of such a term. Structure can refer to the organization of elements on a macro scale, such as in a laminated beam, as well as to the arrangement of cellulose molecules in the crystalline region of an elementary fibril.This presentation focuses on a structural domain that appears increasingly to be a critical one in wood behavior-ultrastructure. The spectrum of terminology that has been used in profusion during the electron microscopic era must first be defined so that confusion is minimized. Then a historical evolution of the field of wood ultrastructure can be presented to provide perspective. Structures that have been shown to affect or indeed to control certain processes can be identified. The role of a non-structure, the elusive transient capillary, can be illustrated. Microfibrillar organization and cell wall archictecture fall into the realm of ultrastructure as well.The past decade of research in wood science has been productive to a significant extent because of scanning electron microscopy and its accessory tools and techniques. The exploration of wood penetration by wood preservatives, pulping liquors and coatings using this approach has yielded much new evidence. One can speculate about the anticipated contributions of computer-driven SEM, stereology, STEM, and even higher resolution microscopy in the near future.  相似文献   

13.
Chemically synthesized (1 5)--d-glucofuranan, (1 5)--d-galactofuranan, (1 5)--d-xylofuranan, (1 5)--L-arabinofuranan, natural xylan, and curdlan were sulfated to investigate their inhibitory activities on B16-BL6 lung metastasis and anticoagulant activities. (1 5)--d-Glucofuranan sulfate, (1 5)--d-galactofuranan sulfate, xylan sulfate, and curdlan sulfate had binding abilities with B16-BL6 melanoma lysate. The inhibitory activities of sulfated polysaccharides on B16-BL6 lung metastasis selected by heparin binding assay were in the order (1 5)--d-galactofuranan sulfate > (1 5)---d-glucofuranan sulfate > xylan sulfate curdlan sulfate. Furthermore, (1 5)--d-galactofuranan sulfate, (1 5)--d-glucofuranan sulfate, and xylan sulfate had not only high inhibitory activity on B16-BL6 lung metastasis but also low anticoagulant activity. The correlation between chemical structure and biological activity is discussed.Part of this paper was presented at the 10th International Synposium on Wood and Pulping Chemistry, Yokohama, Japan, June 1999  相似文献   

14.
Zusammenfassung Unterschiedliche Vektoreignungen können zwischen Rassen, Morphen und Altersstadien einer Blattlausart auftreten. Es wurden verschiedene Morphen vonMacrosiphum euphorbiae (Thomas) undAcyrthosiphon pisum (Harris) hinsichtlich ihrer Übertragungsfähigkeit für das persistente Enationenvirus der Erbse geprüft. Dabei erwiesen sich ovipare Weibchen und adulte Männchen vonM. euphorbiae als ungeeignete Überträger, während die gleichen Morphen von zweiA. pisum-Populationen die Virose übertrugen. Auch die Fundatrix desA. pisum-BastardsTrifolium pratense rot XSarothamnus scoparius grün übertrug zu einem relativ hohen Prozentsatz. Ovipare Weibchen und Männchen der inaktiven RasseLotus uliginosus gelb konnten keine Infektion bewirken; die persistente Virusübertragungsfähigkeit ist im Falle vonAcyrthosiphon pisum (Harris) offenbar ein genetisch fixiertes Merkmal.
Summary Different vector abilities may exist between races, morphs and development instars of a given aphid species. Several morphs ofMacrosiphum euphorbiae (Thomas) and ofAcyrthosiphon pisum (Harris) were tested in their transmission ability for the persistent pea enation mosaic virus. Oviparous females and adult males ofM. euphorbiae proved insuitable for transmission, the corresponding morphs of twoA. pisum-populations, however, were successful in transmitting. The fundatrix of theA. pisum hybridTrifolium pratense red xSarothamnus scoparius green transmitted to a relatively high percentage. Oviparous females and males of the inactiv raceLotus uliginosus yellow failed completely in transmitting; in the present case ofA. pisum the transmission character of the persistent virus evidently is genetically fixed.

Résumé Différentes aptitudes de vecteur peuvent se trouver entre les races, les morphes et les périodes d'âge d'une espèce de pucerons. Différentes morphes deMacrosiphum euphorbiae (Thomas) et deAcyrthosiphon pisum (Harris) ont été examinées en ce qui concerne leurs aptitudes de transmettre le virus persistant du pois(pea enation mosaic). En ce cas les femelles ovipares et les mâles adultes deM. euphorbiae se montraient impropres à la transmission, pendant que les mêmes morphes de deux populations deA. pisum transmettaient la virose. C'était la fondatrice du bâtard deA. pisum Trifolium pratense rouge avecSarothamnus scoparius vert qui transmettait à une pourcentage relativement haute. Les femelles ovipares et les mâles de la race «inactive» deLotus uliginosus jaune ne pouvaient pas effectuer d'infection; en cas deAcyrthosiphon pisum (Harris), l'aptitude persistante à transmettre le virus évidemment est un caractère fixé d'une façon génétique.

, . Macrosiphum euphorbiae (Thomas) Acyrthosiphon pisum (Harris) peaenation mosaic virus). M. euphorbiae , {A. pisum} . A. pisum-Trifolium pratense Sarothamnus scoparius . «» Lotus uliginosus ; Acrythosiphon pisum (Harris) .
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15.
Zusammenfassung Reflexionen zu dem offenen Problem, inwieweit Imagines necrophager Dipteren, — deren Maden im Zentralnervensystem von an Tollwut(Lyssa) verendeten Wirbeltieren zur Entwicklung gelangten —, logischerweise als eventuelle direkte (durch Kontakt-Infektion) oder indirekte (z. B. als Beute von Fledermäusen) Vektoren dieser Virose verdächtigt werden könnten —?
Summary Reflections belonging the open problem, how far imagines of necrophagous dipters, — if theirs maggots developed in the nervecentre-system of such vertebrats, which succumbed by lyssa —, logically are suspected, perhaps to be vectors of this virose, either directly (by contact-infection) or indirectly (for example to be prey to the bats) —?

Résumé Rèflexions à ce propos de discuter le problème ouvert, jusqu'à quel point les individues volants des diptères necrophages, — dont mites se developpaient au milieu du système nerveux central de vertébrés, succombés par lyssa —, sont soupçonnés logiquement d'être peut-être des vectors de cette virose, ou directement (par mettre en contact infectieux) ou indirectement (par exemple d'être butin des chirotères) —?

, , (Imagines), —, , (Lyssa) — ( ) ( ) .
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16.
The effects of prolonged smoke-heating treatments on wood quality were investigated. Six Japanese softwoods were smoke-heated for 100 and 200h at a temperature of 75° ± 5°C, which was recorded inside the log. After smoke heating, wood quality, including moisture content, amounts of chemical components, relative degree of crystallinity (RDC) of cellulose, and sapwood color were examined. Moisture content decreased as a result of smoke heating, especially in sapwood, leading to a uniform distribution of moisture content within a log. Almost no difference was found in the amounts of chemical components between the control woods and the woods that were smoke-heated for 100h. However, in the wood that was smoke-heated for 200h, the amounts of holocellulose decreased, suggesting that thermal deterioration and/or degradation of hemicelluloses had occurred. We assume that the increase in RDC was caused by smoke heating with the crystallization of cellulose and/or thermal degradation of hemicelluloses. Almost no differences were found in sapwood color between the control woods and the woods that were smoke-heated for 100h. In the wood that was smoke-heated for 200h, however, L*decreased, whereas a* and b* increased. As a result, E*ab, showing the total color change, increased, resulting in a deeper color. These results suggest that thermal degradation of hemicelluloses was caused by smoke heating for over 100h. Therefore, smoke heating of softwood logs using a commercial-scale kiln should not exceed 100h.  相似文献   

17.
Summary A -d-(13)-linked glucan has been isolated from compression wood of tamarack [Larix laricina (Du Roi) K. Koch]. The polysaccharide, which had []D + 17.6°, consumed 0.17 mole of periodate per glucose residue and gave a methyl derivative which consisted of 115 2,4,6-tri- and 2,3,4,6-tetra-O-methyl-d-glucose residues in a ratio of 17.8:1. Partial acid hydrolysis yielded a series of -d-(13)-linked oligosaccharides, while enzymic hydrolysis with a -1,3-glucanase afforded glucose, laminaribiose, and laminaritriose. The glucan occurred in amounts varying from 2 to 4% in compression wood of this and other conifer species and was present in the wall of both tracheids and ray cells. It is proposed that this structural polysaccharide be designated as laricinan to distinguish it from callose and the various -1,3-glucans in lower plants.  相似文献   

18.
A contribution to the definition of the fiber saturation point   总被引:3,自引:0,他引:3  
Summary There is hardly any term in wood science literature that has been defined so many times as the term fiber saturation point (FSP). In spite of this fact the discussion is still going on how to define and how to measure it. The aim of the paper is to evaluate some of the known definitions and propose a method of experimental measurement of FSP. The term cell wall saturation, in contrast with FSP, is clearly defined quantity that can be easily measured.The authors are grateful to the Slovak Grant Agency for Science for partial support of this work  相似文献   

19.
Summary It is demonstrated that there can be only one driving potential for the movement of water through wood and this will be a function of wood state. On the assumption that the driving potential is the partial pressure of water vapour, a theoretical expression is derived for the diffusion coefficient. Such expression is fitted to diffusion coefficients for Scots pine and a remarkably good fit is obtained.Symbols a reciprocal mean radius of curvature of a capillary meniscus; also taken to be the radius of the corresponding exposed liquid surface, m - b spacing between flow paths in the cell wall, m - D diffusion coefficient for water in wood with vapour pressure as the driving potential, kg/ms Pa - Da diffusion coefficient for water vapour through air, kg/ms Pa - D diffusion coefficient for water in wood with the driving potential - D diffusion coefficient for water in wood with the driving potential - D0 diffusion coefficient for water in wood with vapour pressure as the driving potential, which is associated with leakage paths through the wood, kg/ms Pa - Df diffusion coefficient for water in wood with vapour pressure as the driving potential, corresponding to fibre saturation and with no leakage paths, kg/ms Pa - Dc diffusion coefficient for water in wood with vapour pressure as the driving potential, which is associated with the constriction of the vapour flow as it approaches the cell wall, kg/ms Pa - D diffusion coefficient for water in wood with moisture content as the driving potential, kg/ms - diffusivity for water vapour in air, m2/s - F flux of water, kg/m2 s - p partial pressure of water vapour, Pa - R specific gas constant for water, J/kg K - r fractional relative humidity - T temperature, K - x length coordinate in direction of flow, m - the dimensionless ratio Df/Dc evaluated at r=1/e - arbitrary driving potential for movement of water in wood - cell spacing in the direction of water flux, m - density of liquid water, kg/m3 - coefficient of surface tension, N/m - arbitrary driving potential for movement of water in wood - fractional moisture content  相似文献   

20.
Bayley  A.D.  Kietzka  J.W. 《New Forests》1997,13(1-3):341-356
Two types of containerized P. patula seedlings, referred to as hard and soft seedlings, were raised by droughting and different fertilizer applications. Hard seedlings were raised by applying half the water and a quarter of the fertilizer (0.01 g per seedling 21%N:7.1%P:14.2%K) applied to the soft seedlings. At the end of the nursery cultural treatments the two types of seedlings were morphologically distinct. Hard seedlings had lower heights, height to root collar diameter ratios and seedling dry masses than soft seedlings, but mortality was similar for both seedling types when planted during seven different production periods within the planting season on three sites which differed climatically and geologically. Correlations between mortality and height to root collar diameter ratio (r = 0.76), root to shoot ratio (r = 0.83) and root growth potential (r = --0.69) were obtained indicating that grading of seedlings on these parameters may improve survival. However, it was evident that survival could be significantly improved by identifying the best time of year and conditions for planting, as well as improving stock quality.  相似文献   

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