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Development, manufacture and application of Beta-Cypermethrin aqueous capsule suspension 总被引:1,自引:0,他引:1
LANGZi-jian SUYuan-ji WANGZhi-ying ChenLi-ping 《林业研究》2004,15(3):218-222
The optimal formula of Beta-Cypermethrin aqueous capsule suspension was screened out through the experiment,preparation and manufacture of basic formulas, which has no sedimentation, suspended drops of oil, peels and agglomerating and the diameter of capsule is in range of 10-30μm, conformed to the technical requirement. The aftereffect of the 3.3% Beta-Cypermethrin aqueous capsule suspension which was manufactured according to the optimal formula was up more than 25 days. The experiments on controlling the larvae of Dendrolinmus superans Butler and the adults of Xylotrechus rusticus L were carried out with different concentrations of this chemical. The death rate reached 80% when 250 times solution of the chemical was sprayed on stem to control the larvae of D. superans. For control of the adults of X. rusticus, 200, 400 and 600 times solution of the chemical were applied and their control effects (death rate) reached 85.23%, 74.21% and 66.59% respectively. Two kinds of solution (200 times and 300 times) of the chemical were used to control the larvae of D. superans in large area, and the control effect for both concentrations was over 90%. 相似文献
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Zusammenfassung Es wird eine Schnellmethode zur Rauchh?rteprüfung von Kiefernarten beschrieben, die vom Terminaltrieb abgetrennte, in Pillengl?ser
gesteckte einj?hrige Kurztriebe verwendet. Die Nadeln reagieren auf akute SO2-Immissionen kloneinheitlich und weitgehend in übereinstimmung mit der Mutterpflanze. Bei den Kurztrieben lassen sich endogene,
vom Mutterbaum abh?ngige Differenzen in der Austrocknungsgeschwindigkeit nachweisen, die aber ohne wesentlichen Einflu? auf
ihre Reaktion gegenüber SO2 bleiben, sofern die Expositionsdauer kurzgehalten wird.
Die entwickelte Methode ist schneller, wirtschaftlicher und auch zuverl?ssiger als Rauchh?rteprüfungen mit eingetopften Pflanzen.
Sie testet lediglich die Reaktion auf akute Begasungen.
Durchgeführt mit finanzieller Unterstützung der Landesanstalt für Immissions- und Bodennutzungsschutz des Landes Nordrhein-Westfalen in Essen. 相似文献
Summary A short-time technique of testing pines for resistance against SO2-emissions has been developed, using one-year-old needle fascicles, put into water-filled glass vials. Against actual SO2-exposure, fascicles of the same tree react uniformly, and their reaction is very similiar to that of the parent tree. Besides, needle fascicles show endogenous clonal variation in the rate of drying out. This, however, does not influence the reaction against SO2, provided the time of exposure is kept short. The new technique is quicker, accurate, and more economical than SO2-tests with potted seedlings or graftings, but it only tests the reaction against short time-high doses exposure to SO2.
Durchgeführt mit finanzieller Unterstützung der Landesanstalt für Immissions- und Bodennutzungsschutz des Landes Nordrhein-Westfalen in Essen. 相似文献
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Wrieden WL Anderson AS Longbottom PJ Valentine K Stead M Caraher M Lang T Gray B Dowler E 《Public health nutrition》2007,10(2):203-211
OBJECTIVE: To evaluate the feasibility of undertaking a food skills intervention study in areas of social deprivation aimed at altering cooking confidence, food preparation methods and dietary choices. DESIGN: A standardised skills programme was implemented in community-based settings. Pre- (T1) and post-intervention (T2) and 6-month follow-up (T3) measures (7-day diaries and self-administered questionnaires) were undertaken in intervention and comparison groups. SETTING: Eight urban communities in Scotland. SUBJECTS: One hundred and thirteen adults living in areas of social deprivation. RESULTS: It was clear that many subjects led fragmented lives and found commitment to intervention classes problematic. Sixty-three subjects completed the final (T3) assessments. The response to each component varied due to inability to attend sessions, illness, study requirements, employment, moving out of the area, change in circumstances, loss of interest and loss of postal questionnaires. At baseline, reported consumption of fruit and vegetables was low (mean frequency 8.1 +/- 4.78 times per week). Fruit intake increased significantly (P < 0.05) between T1 and T2 in the intervention group (1.7 +/- 2.36 to 2.7 +/- 3.28 times per week) only. Between T1 and T3, there was a significant increase (P < 0.05) in intervention subjects who reported confidence in following a recipe (67-90%,). CONCLUSIONS: This exploratory trial shows that a food skills intervention is likely to have a small but positive effect on food choice and confidence in food preparation. A full-scale randomised controlled trial in this hard-to-reach group would require a range of flexible approaches rather than a fully defined intervention, and presents challenges for trial design. 相似文献
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近年来,榆林大力发展山地苹果,集中连片栽植,规模较大,为进一步培养树形,提高果实产量,本试验以长富2号、烟富3和瑞雪为试材,研究简易化快速整形修剪技术,对果树栽后第二年、第三年冬剪连续两年抹光杆(保留中央领导干延长头),调查其五年生树体生长量和2015-2019年产量。结果表明:采用二年抹光杆修剪技术,能够显著提高幼树生长势,加快树形培养;长富2号五年生干径较对照增粗2.03cm,分枝数较对照增加5.7个,枝干比较对照降低0.36,中短枝比例显著增加,短枝比例较对照升高19.7%。2019年(九年生)长富2号产量1 815.7 kg/667 m2,较对照增收1 309.2 kg,2015-2019年累计产量为5 323.7kg,较对照增加3 438.0 kg,每年较对照平均增产687.6 kg,增产效果显著。 相似文献
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Hannah J. Munro Lesley Berghuis Andrew S. Lang Laura Rogers Hugh Whitney 《Canadian journal of veterinary research》2014,78(2):140-144
Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are retroviruses found within domestic and wild cat populations. These viruses cause severe illnesses that eventually lead to death. Housing cats communally for long periods of time makes shelters at high risk for virus transmission among cats. We tested 548 cats from 5 different sites across the island of Newfoundland for FIV and FeLV. The overall seroprevalence was 2.2% and 6.2% for FIV and FeLV, respectively. Two sites had significantly higher seroprevalence of FeLV infection than the other 3 sites. Analysis of sequences from the FeLV env gene (envelope gene) from 6 positive cats showed that 4 fell within the FeLV subtype-A, while 2 sequences were most closely related to FeLV subtype-B and endogenous feline leukemia virus (en FeLV). Varying seroprevalence and the variation in sequences at different sites demonstrate that some shelters are at greater risk of FeLV infections and recombination can occur at sites of high seroprevalence. 相似文献