GC/MS结合程度相似度用于烟用香精质量评价

[目的]为烟用香精质量评价提供新方法。[方法]采用GC/MS法建立烟用香精指纹图谱,对6批次CW#烟用香精样品,计算其相关系数、夹角余弦和程度相似度。[结果]GC／MS结合程度相似度算法能够有效地反映样品间的整体差异。[结论]该方法准确、可行,可作为烟用香精质量评价的一种直观、合理、有效的技术手段。     

小麦花粉白化苗成因的研究——Ⅱ.小麦花粉愈组和花粉苗的同工酶分析

花粉白、绿苗同工酶的分析表明,花粉白苗的过氧化物酶的酶谱上,有一条相对迁移率为0.34～0.36的“特征带”。而花粉绿苗的酯酶的酶谱上,有一条与β—萘酯起作用的“特征带”。花粉愈伤组织过氧化物酶的同工酶分析表明,愈伤组织苗色的分化方向似乎在愈伤组织阶段或在此之前便决定了的,再分化的培养条件对苗色的分化不再起作用。花粉白苗叶绿素吸收光谱分析表明,小麦白苗仍会有少量叶绿素a和叶绿素b,这就排除了白苗的产生是由于愈伤组织细胞的旺盛分裂及生理上障碍致使细胞质体缺失所致。     

Finite dose diffusion studies: III. Effects of temperature, humidity and deposit manipulation on NAA penetration through isolated tomato fruit cuticles

Effects of temperature, humidity, rewetting and removal of deposits on penetration of NAA [2-(1-naphthyl)acetic acid] through isolated tomato (Lycopersicon esculentum Mill) fruit cuticles were studied using a finite dose diffusion system. In this system, an aqueous 5-microliter droplet (0.1 mM NAA in 20 mM citric acid buffer) is applied to the outer surface of a cuticle, which is mounted in a glass diffusion half-cell. The cell wall surface is in contact with a receiver solution (20 mM citrate). Penetration is monitored by repeated sampling of the receiver solution. Droplets appeared dry on visual inspection within 1 h of application, but significant NAA penetration continued after droplet drying. Maximum rates of NAA penetration increased exponentially as temperature was increased (from 5 degrees to 35 degrees C), the energy of activation averaging 153 (+/- 11.6)kJ mol-1. At 35 degrees C, penetration reached a plateau within 10 h of application (at 91.1 (+/- 1.0)% of dose applied) while at 5 degrees C penetration after 800 h reached only 30.2 (+/- 7.5)%. Increasing relative humidity from 20 to 80% increased maximum rates [from 1.0 (+/- 0.21) to 2.7 (+/- 0.80)% h-1] and penetration at 120 h after application [from 36.8 (+/- 2.1) to 64.3 (+/- 3.7)%]. Rewetting deposits at 120, 240 and 360 h after application resulted in increased NAA penetration. However, amounts and rates of NAA penetration progressively decreased with each subsequent rewetting. Removal of deposits by cellulose acetate stripping at various times after droplet application resulted in a rapid decrease in NAA penetration. NAA penetration following deposit removal was always less than 6.1% of the amount of NAA applied and averaged 0.5 (+/- 0.2)% when deposits were removed immediately after droplet drying.     

新型解毒剂T对异噁草松造成玉米药害的缓解作用

通过测定植株叶绿素含量与荧光光谱特征动态变化，分析除草剂异FDB8草松和解毒剂T 对玉米植株的生理作用。随着除草剂浓度升高，叶绿素浓度下降，单位叶绿素荧光强度比不 断上升，而解毒剂T可缓解上述伤害。     

双核丝核菌诱导水稻增强广谱抗病性和防卫酶系活性

 用无致病性的双核丝核菌(Binucleate Rhizoctonia species,简称BNR)菌株2 32-CG预接种处理水稻品种IR2 6苗期植株根茎基部,可以诱导水稻增强对纹枯病(R.solani Kühn)的抗性。与未处理对照相比,BNR处理水稻植株的纹枯病害严重度明显降低。2 4 h以上的BNR处理,可以彻底保护幼苗不受立枯丝核菌侵染的危害。经BNR诱导的水稻也表现对白叶枯病(Xanthomonas oryzae pv.oryzae)和条斑病(X.oryzae pv.oryzicola)的抗性。BNR可以显著地诱导水稻防卫反应中的2类关键酶——苯丙氨酸解氨酶(PAL)和过氧化物酶(POX)活性提高。受BNR诱导的抗病性与PAL和POX活性呈正相关。对BNR在水稻病害生物防治中的作用进行了讨论。     

塔里木盆地地区沙尘气溶胶特征分析

沙尘天气是塔里木盆地地区常见的天气现象 ,对沙尘气溶胶的分析表明 ,尘暴期间 ,沙尘气溶胶浓度远大于非尘暴期间。沙尘气溶胶小颗粒绝对浓度大幅度增加 ;百分比含量也迅速增加 ;小颗粒 ( <3.3um)与大颗粒 ( >3.3um)的相对浓度呈大幅度增加趋势 ,说明尘暴期间由于当地沙源丰富 ,细物质较多 ,细小颗粒迅速被携带到高空 ,成为沙尘气溶胶的主要来源。阿克苏站气溶胶中 Al等元素在不同高度的谱分布呈单峰型 ,浓度最大值出现在 4.7- 7.0 um范围内。富集因子分析表明 ,阿克苏站和策勒站沙尘暴和扬尘天气的各地壳元素含量均高于浮尘和背景大气 ,而且能见度愈小 ,高出的比例愈大 ;各种沙尘天气发生时 ,均以亲地元素的浓度为最高。     

恩诺沙星免疫抗原与检测抗原的制备及鉴定

采用N-羟基琥珀酰亚胺法将恩诺沙星（Enro）半抗原与载体蛋白-牛血清白蛋白（BSA）相偶联，制备出了抗Enro单克隆抗体的免疫抗原Enro-BSA。同样的方法，将Enro与卵清白蛋白（OVA）相偶联制备了抗Enro单克隆抗体的检测抗原Enro-OVA。紫外扫描光谱及动物免疫试验结果表明，其偶联成功。     

Estimation of the base line imagined as a muscular background for myoglobin determination by reflectance spectrometry

Liquid extraction method for determination of myoglobin in muscle is not suitable because of changes in the derivatives and time required. Optical reflectance method is useful as a non‐destructive and real‐time measurement. However, the base line of reflectance method, the muscular reflectance background (MRB) imagined as colorless structural elements, has been unknown because of non‐existence. The spectrum of the base line was analyzed as the analogy of bleached meat. A formula was derived for reflectance that had a linear relationship to the reciprocal of wavelength to the power 4. The reflectance characteristic of the MRB was not constant and the curve tended to rise with increasing wavelength. The reflectance at 700 nm was estimated to be 50%. By the characteristic analysis on Commission Internationale l’Eclairage color values and reciprocal reflectance, it was concluded that the reflectance spectrum of the muscular background obtained in this research was fitted as a base line for the reflectance spectrometry.     

Reviews Section: The Motax 33 -- motorized, portable, air- assisted, CDA sprayer

The Motax 33, a portable air-assisted controlled droplet application (CDA) sprayer, offers a new approach to the application of pesticides within coffee and other bush crops. It uses a rotary atomizer to produce small, uniformly sized droplets which are propelled into the crop foliage by a wide and turbulent air blast, allowing the use of low spray volumes. Compared with traditional high-volume techniques the sprayer offers the possibility of improved spray coverage and penetration at low spray volumes, typically 30--70 l ha–1, allowing more timely spray treatments with the potential to adopt more responsive integrated insect pest and disease management strategies     

亚洲玉米螟为害后玉米冠层光谱变化和产量损失研究

2006年在河北农林科学院植保所农场夏播高感亚洲玉米螟的玉米品种郑单958上,于大喇叭口期人工接种2龄玉米螟幼虫以造成不同梯度为害,利用便携式遥感光谱仪(ASD FieldSpec UV/VNIR)在玉米不同生育期收集冠层光谱信息,调查食叶级别,并在收获时统计蛀孔率和产量。结果表明:(1)各生育期食叶级别和对应生育期内的冠层光谱反射率值呈显著负相关,且各个级别之间方差分析差异显著;(2)各波段冠层光谱反射率值和每株虫孔数量的相关性分析得到相关性曲线,750～900nm相关系数较高,可作为监测的敏感波段;(3)乳熟期光谱数据、平均每株虫孔数量和产量及产量损失率之间均可建立极显著回归方程。用光谱仪所测数据估测产量损失率的精确度比用传统查虫数据估测产量损失率的精确度高,且省时省工。