Foliar spectral properties following leaf clipping and implications for handling techniques

After leaves are clipped their reflectance properties change over time at variable rates. Spectral change can in part be attributed to the changing water content of the leaf, which affects absorption in the VIS, NIR and the SWIR. Maintaining water volume within samples has been the motivation behind many leaf handling techniques. This study has assessed the time constraints between leaf collection and spectral measurement. Specifically the relationship between leaf water content and foliar spectra (350-2500 nm) was examined over time for five tropical trees (common guava (Psidium guajava), purple guava (Psidium littorale), weeping fig (Ficus benjamina), floss silk (Chorisia speciosa), and coffee (Coffea arabica)). This investigation was carried for leaves wrapped with moist gauze around their petiole (treatment leaves) and leaves with no treatment. Spectral measurements and mass measurements were repeated for each leaf once every hour for the first 12 h, then every 4-6 h for 18 h, followed by one measurement after 12 h, and finally once a day until the control samples became air-dry. Foliar reflectance in the visible spectrum was not immediately responsive to water content changes and did not change until wilting of the leaf was observed. The NIR and SWIR wavelength regions were affected immediately by small changes in water content. Thus, by the time wilting was first observed the NIR and SWIR foliar reflectance differed considerably from corresponding fresh leaf reflectance. No common time limit could be observed for leaf clipping and reflectance measurement. Leaves have a variety of water contents and dehydration rates hence measurement time constraints are dependent on the properties of the leaf or species. Rather than using a time limit it is recommended that leaf handling techniques be based upon managing leaf water content and leaf structure. The results of this study indicate that leaves with petioles wrapped in moist paper towel and placed within plastic bags will maintain leaf reflectance longer than equivalent leaves without treatment; samples tested here lasted a minimum of 7 days. θ and D indices (“angle difference” and “root mean square difference”, respectively) revealed a stronger relationship between leaf water content and spectral shape than between leaf water and raw reflectance magnitude. The ratio of 1187/1096 nm, when compared with θ and D indices and individual reflectance bands, showed the highest coefficient of determination with leaf water content (r² = 0.952).     

玉米灰斑病研究进展

玉蜀黍尾孢菌（Ｇｅｒｃｏｓｐｏｒａｚｅａｅ－ｍａｙｄｉｓ）引起的玉米灰斑病目前已经发展成一重要病害。该病主要发生在温暖、湿润的地区，各玉米品种之间的抗病性存在明显差异，其抗病性主要受附加基因控制国内外都有一些抗病品种，但是多数品种感病。     

水稻细菌性条斑病抗性基因定位

以高感和高抗细菌性条斑病（细条病）的两个籼稻品种Ｈ３５９和Ａｃｃ８５５８为亲本，建立了一个重且自交系群体。利用该群体构建了一张包含２２５个分子标记的连锁图。１９９６年和１９９７连续两年对该群体进行了细条病抗性鉴定。采用ｔ测验法、复合区间定位法及多性状复合区间定位法对细条病抗性基因（ＱＴＬ）进行了定位分析。共检测出１１个ＱＴＬ，分别位位于第１、２、３、４、５、７、８和１１号染色体上，效应大小彼此接近     

Sensory Responses To Environmental Tobacco Smoke From Tobacco-Burning And Tobacco-Heating Cigarettes

Sensory ratings, respiratory behavior and eye blink rate were recorded in 11 nonsmokers exposed to a no-smoking (CONTROL) condition or to environmental tobacco smoke (ETS) from one of three kinds of cigarettes: a Kentucky reference (1R4F), an ultra-low tar (ULT) and one that heats tobacco (TEST).For each two-hour session in a controlled-environment room, two smokers “puffed” unlit cigarettes, for the CONTROL condition, or smoked 16 cigarettes to generate ETS (sidestream plus exhaled mainstream smoke). Concentrations of nicotine and respirable suspended particles (RSP) observed with the 1R4F and ULT cigarettes were 10- to 20-fold higher than those typically found in field sampling studies of office and restaurant smoking environments. The ULT and TEST cigarettes resulted in ETS analyte concentrations that were 77-100% and O-56%, respectively, of those observed with 1R4E Sensory ratings (odor, irritation, annoyance, acceptability) with the two tobacco-burning cigarettes were similar and were much greater than those recorded for the TEST or CONTROL conditions which were, in turn, rated similarly. Respiratory parameters (respiratory rate, tidal volume, expiratory time), which generally failed to discriminate the TEST and CONTROL conditions, were altered during exposure to ETS from the 1R4F and, to a lesser extent, the ULT cigarette. Eye blink rate was not significantly altered by ETS from any of the cigarettes.     

Supplementation of oils with oleanolic acid from the olive leaf (olea europaea)

A method was studied for utilization of olive leaf, which is a byproduct of olive tree pruning and olive oil production. Our strategy involves two stages. The first is a simple procedure for isolating oleanolic acid, a compound with known biological activity. The second stage involves supplementation of different types of oil with this triterpenic acid. Two protocols were used for incorporating this acid into oils, either as a solid or as a solution, at concentrations from 200 to 1000 ppm. Oleanolic acid in the prepared oils was quantified by gas liquid chromatography. At the concentrations analyzed, the oleanolic acid content measured in all oil samples was equal to the amount added (p <0.05). No significant difference was observed (p <0.05) between the two supplementation procedures in any of the oils.     

连续萃取法从废烟叶中提取烟碱

本文用三氯乙烯连续萃取废物烟草浸出液以提取化工原料烟碱获得成功，文中给出了提取的工艺条件和生产流程。     

I-DEAS软件Manufacturing模块应用探讨

介绍如何应用I-DEAS软件的Manufacturing功能,进行烟草机械中异型零件的复杂曲面的加工.以便实现零件的设计、工艺分析和加工一体化,从而提高烟草机械中复杂曲面的表面质量.     

富马酸二甲酯在烟叶仓储防霉中的应用试验

对富马酸二甲酯(DMF)熏蒸法和直接添加法应用于烟叶仓储防霉的效果分别进行了试验。结果表明,DMF对烟叶仓储防霉具有效果良好、操作简便易行和成本低廉等优点,其中直接添加法还能避免熏蒸法对部分人体产生的过敏反应,具有推广应用价值。     

银杏叶洗发香波的研制及评价

实验中通过红外光谱和显色反应的定性分析来确定银杏叶提取物的主要成分，介绍了银杏叶黄酮类化合物的防脱发功效，考察了阴离子表面活性剂的组成对泡沫性能的影响，同时考察了银杏叶提取物的加量对洗发香波各项性能的影响。结果表明，采用阴离子表面活性剂K12-A与AES复配，可进一步提高洗发香波的泡沫性能，其中K12-A在阴离子表面活性剂中的最佳含量为25％；银杏叶提取物用量以3％，5％为宜。根据国家标准检验证明，银杏叶洗发香波具有防脱发和去屑止痒的功效，且生产工艺简单。     

师宗烟叶复烤厂消防给水设计

介绍了师宗烟叶复烤厂消防给水设计的情况,重点介绍了室外消火栓箱、室内消火栓水枪充实水柱的反向计算,闭式水幕系统及其互联锁控制系统,可供有关单位参考。