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71.
72.
Müller T Brancq B Milius A Okori N Vaille C Gauvrit C 《Pest management science》2002,58(12):1243-1249
Ethoxylates of rapeseed oil and of methylated rapeseed oil were synthesized and tested as adjuvants for 2,4-D and phenmedipham. Provided they had less than 6 units of ethylene oxide (EO), 1.0 to 10 g litre(-1) ethoxylates in water induced droplet spreading on barley leaves. In an acetone-based medium all derivatives strongly promoted the foliar uptake of 2,4-D, with no clear influence of the ethoxylation degree. In the same medium there was a negative influence of ethoxylate chain length on the foliar uptake of phenmedipham. In a water-based medium, phenmedipham applied with rapeseed oil emulsified with ethoxylated (20 EO) rapeseed oil displayed uptake rates close to a commercial preparation. The same was true for phenmedipham applied with ethoxylated (2 EO) methylated rapeseed oil. In bioassays, phenmedipham prepared with methylated rapeseed oil emulsified with ethoxylated (20 EO) rapeseed oil was as efficacious on barley as a commercial formulation. The same was true for phenmedipham prepared with ethoxylated (2 EO) methylated rapeseed oil. However, neither rapeseed oil nor methylated rapeseed oil emulsified with ethoxylated (2 EO) methylated rapeseed oil conferred good efficacy to phenmedipham. Hence, ethoxylated rapeseed oil derivatives are promising adjuvants or formulants for herbicides. 相似文献
73.
Allison D Tuttle Mark Papich Gregory A Lewbart Shane Christian Conny Gunkel Craig A Harms 《Journal of zoo and wildlife medicine》2006,37(4):567-570
The nonsteroidal antiinflammatory drug ketoprofen (KTP) is a commonly used antiinflammatory and analgesic agent in reptile medicine, but no studies documenting its pharmacokinetics in this species have been published. Ketoprofen was administered as a racemic mixture to green iguanas (Iguana iguana) intravenously (i.v.) and intramuscularly (i.m.) at 2 mg/kg. Pharmacokinetic analyses were performed and indicated that ketoprofen in iguanas administered by the intravenous route has a classical two-compartmental distribution pattern, a slow clearance (67 ml/ kg/hr) and a long terminal half-life (31 hr) compared to ketoprofen studies reported in mammals. When delivered by the intramuscular route, bioavailability was 78%. These data indicate the daily dosing that is generally recommended for reptile patients, as an extrapolation from mammalian data, may be more frequent than necessary. 相似文献
74.
海克军 《四川畜牧兽医学院学报》2006,4(1):206-208
大学生就业难是社会普遍关注的焦点问题之一。大学生就业中的伦理道德缺失不容忽视。要解决这一问题,除学校加强道德教育、企业提升自身魅力外,根本在于大学生自身的觉悟与个人素养的提高。 相似文献
75.
以6个苹果品种为试材,进行苹果的有效负载面积与产量相关性试验.结果表明:在一定条件下,有效负载面积(EBS)越大,产量相应越高.不同纬度对不同品种的EBS和产量的影响不同.土壤中砾石含量对EBS和产量都有影响,但品种和砧木不同,EBS的减少率不同.不同品种对砾石的耐受能力不同. 相似文献
76.
Joseph Aubert Mouen Bedimo Daniel Bieysse Ibrahim Njiayouom Jean Pierre Deumeni Christian Cilas Jean Loup Nottéghem 《European journal of plant pathology / European Foundation for Plant Pathology》2007,119(4):391-400
In the high altitude regions of Africa, coffee berry disease (CBD), caused by Colletotrichum kahawae, is the main constraint for arabica coffee (Coffea arabica) production. However, certain agricultural practices can reduce losses caused by the disease and thereby promote optimum
production. On small family farms in Cameroon, mixed cropping with fruit trees, intercropping with food crops and maintenance
pruning of coffee trees are very widespread agricultural practices that can affect CBD epidemics. Consequently, an epidemiological
study was conducted to assess how cultural practices affected the disease in an arabica coffee smallholding in Cameroon. The
disease was monitored on a weekly basis over four successive years (2002–2005) on coffee trees in diverse cultural situations.
Cultural practices likely to reduce losses due to CBD were identified. The infection rate was significantly lower on coffee
trees grown intensively than on coffee trees grown in the traditional manner. Coffee trees located under the shade of fruit
trees were significantly less attacked than those located in full sunlight. In addition, berries on the leafless parts of
branches, near the main trunk of the coffee tree, were less infected than those on leafy sections. These results show that
maintenance pruning, removal of mummified berries, and mixed cropping with shade plants are cultural practices which create
environmental conditions that limit CBD development. 相似文献
77.
Abstract. Nitrate leaching under newly planted Miscanthus grass was measured for three years. The crop received either no fertilizer-N or an annual spring application of 60 kg or 120 kg N ha-1 . During three winters soil water was collected from porous cup probes installed 90 cm deep. Nitrate leaching was calculated from the mean drain flow recorded in two drain gauges multiplied by the mean nitrate-N concentration in the soil water solutions collected. In the first year soil water nitrate concentrations were high on all treatments and N losses were 154, 187 and 228 kg ha-1 respectively on the unfertilized treatment and those that received 60 or 120 kg N ha-1 . Leaching losses in the second and third years were, in turn, 8, 24 and 87 kg ha-1 and 3, 11 and 30 kg ha-1 for the unfertilized treatment and for the 60 and 120 kg N ha-1 treatments respectively. Leaching losses were closer to those recorded under extensively managed grassland than arable land. The large losses in the first year were probably due to the previous agricultural management at the site and excessive inputs of N on the fertilized plots. In the second and third year, lower drainage volumes may also have influenced losses. The results show that Miscanthus , once established, can lead to low levels of nitrate leaching and improved groundwater quality compared with growing arable crops. 相似文献
78.
79.
Summary Dynamic methods provide rapid and accurate means to determine Young's modulus, i.e. the modulus of elasticity, of wood. For dry, clear specimens of épicéa commun (Norway spruce, picea excelsa) and sapin pictiné (silver fir, abies amabilis) we present a comparison of results from tests by a resonance flexure method with results obtained from four-point static flexure tests. For a wide range of specimen size the resonance flexure method provides a simpler, more rapidly performed alternative to the classical static flexure method, giving Young's modulus values which are for the spruce and fir specimens of this study, nearly identical to those calculated from the static flexure tests. Results are also presented which show that a resonance longitudinal method yields higher values of Young's modulus and an ultrasonic method yields still higher values. We provide also a comparison of the four test methods applied to isotropic materials.The authors wish to thank Pierre Michel and André Perrin for preparing the test specimens and components of the test apparatus for this study 相似文献
80.