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The same technique of proof is also applied to yield an existence result for A-dilation MRA subspace wavelets.
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We obtain the Holder exponents of such fractal interpolation functions by using the technique of operator approximation.
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By introducing a kind of maximal operator of fractional order associated with the mean Luxemburg norm and using the technique of Sharp function, multilinear commutators of fractional integral operator with vector symbol b = (b1,...bm)defined by
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To circumvent this difficulty, this paper presents a novel hybrid numerical technique of combined difference and spectrum for time-domain Maxwell's equations.
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This paper proposes a technique of image content authentication based on the Laplacian Pyramid to verify the authenticity of image content.
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| The present paper gives a report on a study of the life his- tory of a destructive pest, Melanauster chinensis Forster, of citrus trees in Foochow during the years 1951 and 1952. It has been found that the adults lay eggs beginning from the last part of May until the end of July. Eggs are inserted in the bark of the tree trunk about 1. 4 inches from the ground. Incubation period lasts from 9 to 14 days. After hatching the young larvae feed under the bark for three or four months. In October they bore into the... The present paper gives a report on a study of the life his- tory of a destructive pest, Melanauster chinensis Forster, of citrus trees in Foochow during the years 1951 and 1952. It has been found that the adults lay eggs beginning from the last part of May until the end of July. Eggs are inserted in the bark of the tree trunk about 1. 4 inches from the ground. Incubation period lasts from 9 to 14 days. After hatching the young larvae feed under the bark for three or four months. In October they bore into the wood from a place about one to two inches above the ground. Overwintering of the larvae in the burrows generally begins in November or December. They resume actti- vity in March the following year. Pupation takes place abou the middle part of April. The pupal period lasts from 18 to 20 days. After emergence the adults remain in the pupal cells in the upper part of their burrows for about five to eight days. The adults appear from the middle part of May to the middle part of August. Burrows made by the larvae under the bark as well as in the wood have been studied carefully. Recommendations have been given to improve the original technique of destroying the larvae by probing with wire. | 星天牛为柑桔主要害虫之一,研究此种害虫者颇不乏人,但就所见文献中关于该虫习性的报道,多不足作为防治的有力参考。笔者有鉴及此,于一九五一至一九五二年在福州研究这一害虫的生活习性,尤其对于幼虫为害的隧道,有比较详细的观察。把果农钩杀幼虫这一防治方法的实践与理论相结合,初步掌握了幼虫在柑桔树干中钻蛀为害的规律,使过去所谓奥妙不可捉摸的钩杀技术得到了解析,同时也把这一技术从现有的水平提高了一步,希望可以为一般从事柑桔栽培工作者所掌握,成为简单易学的一件事。五月下旬至七月下旬均有成虫产卵,产卵位置平均离地面1.4寸,卵期九至十四天。幼虫孵化后即从产卵处蛀入,向下蛀食于表皮与木质部之间,其向下蛀食范围多在地面下五寸以内。一般在三、四个月后亦即在十月左右,以成熟或将成熟的幼虫,蛀入木质部内,作一隧道,准备过冬及化蛹。蛀入孔多在地面下—、二寸处。一般幼虫在十—、二月开始休眠越冬,历时约三、四个月,翌年三月以后又开始恢复活动。四月中旬开始化蛹,蛹期十八至二十天。成虫羽化后在蛹室内停留五至八天。自五月中旬至七月中旬都有成虫出现,迄八月中旬仍见有极少数成虫。幼虫所营隧道的形状、长短,都有一定的规律,文中有详细的叙述,并附有图解。 | Introducing the notion and technique of communication theory theauthor shows that the evaluation of weather forecasting could be improved.The information index is used as an index of evaluation.It is also pointedout that any modification of the forecast done arbitrarily must decrease itsvalue as an information. | 作者利用讯息论中的概念和方法说明现用天气预报评分的缺点和改进方法.讯息量或讯息指数可以作为评分的一种指标.作者又指出对天气预报随便改动必然降低预报的情报价值,因此使用单位不宜任意改动. | The study of the paper chromatography of organic acids was undertaken to provide a simplemethod for the identification of the organic acids in plant tissues.With the technique of ascend-ing development,the R_f values of seven organic acids were determined as follows:With the exception of the R_f values of oxalic acid,these values agree generally with thosefound in the literature.Temperature variations have no apparent influence on the R_f values ofthe organic acids examined.Different from other organic... The study of the paper chromatography of organic acids was undertaken to provide a simplemethod for the identification of the organic acids in plant tissues.With the technique of ascend-ing development,the R_f values of seven organic acids were determined as follows:With the exception of the R_f values of oxalic acid,these values agree generally with thosefound in the literature.Temperature variations have no apparent influence on the R_f values ofthe organic acids examined.Different from other organic acids,oxalic acid left long trails on the chromatograms andthis trailing was not eliminated by an increased concentration of the swamping acid HCOOH.Experiments have shown that only when the concentration of the oxalic acid solution applied issufficiently high(above 0.5 M),can a well defined spot be seen at the end of the trail and onlythis spot appears to have a constant R_f value.On the other hand,when the concentration ofthe test solution is comparatively low(below 0.5 M),no spot can be seen on the chroma-togram,except a diffuse trail,the length of which is found to vary with the concentration of theacid applied,being less at the lower concentrations.The R_f values of oxalic acid reported inthis paper are obtained on the condition that only concentrated solutions(above 0.5 M)of theacid are used and only the excursions of the well defined spots at the ends of the trails are basedfor calculations.A modified method for the chromatographic detection of organic acids from plant tissuesis here described.In order to overcome the difficulty in differentiating the acids of similarmobilities and to avoid the possible loss of acids from detection,it is proposed to develop twochromatograms for each sample with two different solvents and also to compare the resultsobtained with both diluted and concentrated solutions of the unknown acids.By this method the leaves of castor-oil plant(Ricinus communis,L.)were found to containtartaric acid,citric acid,malic acid,and fumaric acid and those of lotus(Nelumbo nucifera,Gaertn)were found to contain gluconic acid,tartaric acid,citric acid,malic acid,oxalic acid andsuccinic acid. | (1)本文分别用戊醇-蚁酸-水和丁醇-蚁酸-水为溶剂测定了酒石酸等七种有机酸的 R_f 值。除草酸外,所有结果与文献记录基本符合。在本文实验的温度范围内(30±4°)温度变化对有机酸的 R_f 值并无显著影响。(2)由于草酸的严重拖尾现象,在一般的操作用量下,草酸试液浓度在0.5M 以下不能生成有固定 R_f 值的斑点。因此草酸 R_f 值必须以0.5M 以上的浓试液进行试验,并须以最高处的深浓斑点作为计算根据。(3)对植物组织中非挥发性有机酸的纸上层析,本文建议用两种 R_f 值相互验证,并用浓试液与稀试液作比较试验,所得结果比较明确可靠。(4)用本方法在蓖麻叶中检出了酒石酸,柠檬酸,苹果酸和延胡索酸四种非挥发性有机酸。在荷叶中检出了葡萄糖酸,酒石酸,柠檬酸,苹果酸,草酸和琥珀酸六种非挥发性有机酸。 | | | | << 更多相关文摘 |
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