Microelements in Potato and Lily Samples Studied by Laser-Induced Breakdown spectroscopy Technology

A LIBS setup was built in the Institute of Modern Physics. In our experiments, LIBS spectra produced by infrared radiation of Nd : YAG nanosecond laser with 100 and 150 mJ pulse energy, respectively, were measured by fiber optic spectrometer in the ranges of 230-430 run and 430-1080 nm with a delay time of 1.7 and gate width of 2 ms for potato and lily samples prepared by vacuum freeze-dried technique. The lines from different metal elements such as K, Ca, Na, Mg, Fe, Al, Mn and Ti, and nonmetal elements such as C, N, O and H, and some molecular spectra from C-2, CaO, and CN were identified according to their wavelengths. The relative content of the six microelements, Ca, Na, K, Fe, Al, and Mg in the samples were analyzed according to their representative line intensities. By comparison we found that there are higher relative content of Ca and Na in lily samples and higher relative content of Mg in potato samples. The experimental results showed that LIBS technique is a fast and effective means for measuring and comparing the contents of microelements in plant samples.

一维位置灵敏法拉第筒的数据获取系统

简要介绍兰州重离子加速器国家实验室320 kV高压ECR实验平台原子分子物理终端上使用的一维位置灵敏法拉第筒的数据获取系统。该系统硬件由64通道电流/电压转换放大器和PCI-6224数据采集卡构成,并通过编写LabVIEW程序,实现数据的准确、同步、实时与高速采集。经验证,该获取系统简单易用,可靠性高,完全符合设计要求。

不同水肥条件对大豆产量的影响

以沈阳生态试验站一组持续17年的长期定位试验为平台,研究了不同降水年景作物对施肥的增产反应,估算了下辽河平原地区水肥交互作用对大豆产量的影响。结果表明,该地区大豆蒸散耗水与其生育期内降水之间关系密切,且不同的施肥处理对大豆消耗水分量影响不大;肥料对产量的影响大于水分的影响,钾肥的施用提高了大豆抗旱能力,随着水分条件的改善磷肥增产作用提高,而水分过多会对大豆造成毒害作用。该地区平、丰水年份磷、钾肥交互作用以叠加效应为主,平水年份各处理大豆产量均达到最高,水肥交互作用对大豆增产贡献亦达到最大。

参与肿瘤侵袭和转移的细胞外基质降解酶

肿瘤细胞在侵袭和转移过程中必需穿透一系列天然组织屏障—基底膜和细胞外基质。合成及分泌大量基质降解酶，降解细胞外基质是肿瘤细胞侵袭、转移的重要步骤［１］。目前所知与肿瘤侵袭、转移有关的基质降解酶有两大类：蛋白酶类和糖苷酶类，前者主要降解细胞外基质中的蛋...

番茄专用肥肥效初步研究

番茄专用肥肥效初步研究刘子江，崔桂霞，武冠云（中国科学院沈阳应用生态研究所）赵彩霞，张玉兴王述麟，王阳（沈阳市于洪区畜牧副食局）（沈阳市东陵区畜牧副食局）随着农业生产的发展和科学施肥技术的实施，专用肥的应用愈来愈广泛。专用肥的使用效果，是肥料研究领域...

~(137)Cs示踪研究小流域土壤侵蚀与沉积空间分布特征

通过在0.17 km~2面积的小流域198个点、525个样品表层土壤中~(137)Cs含量的分析、研究,结果表明:不同地貌部位~(137)Cs含量有明显分异,为~(137)Cs法定量研究土壤侵蚀与沉积提供了科学依据;~(137)Cs含量升高的部位多出现在沟缘线附近和沟口附近;小流域土壤侵蚀强度从梁峁顶向沟坡逐渐增大,这是黄土高原广大水土流失区自然状态的或初步治理的小流域侵蚀强度空间变化的基本特征.

氮磷配合对土壤氮素径流流失的影响

大田试验研究结果表明 :增施N、P均能增加作物的产量和减少水土流失 ;当N、P用量分别达到 5 5 .2kgN/hm2 和 90kgP2 O5/hm2 时 ,泥沙有机质和全氮流失最少 ,流失量分别为 2 0 89和 1 75kg/km2 ;当N、P用量分别为 5 5 .2kgN/hm2 和 4 5kgP2 O5/hm2 时 ,土壤矿质氮流失最小 ,其流失量仅为 2 7.9kg/km2 ;作物对土壤氮素的吸收 ,可减少土壤氮素的流失 .

小柏根和白石清热冲剂废渣栽培平菇试验

小柏根和白石清热冲剂废渣栽培平菇试验姚志红（中国科学院沈阳应用生态所，１１００１５）随着食用菌栽培业的迅速发展，棉子皮等一些传统生产原料供不应求或价格过高的问题日趋突出，在非产棉地区更成了生产发展的限制因素。因此，不断挖掘当地可利用的潜在资源，开辟新...

Magnetic control of bioelectrocatalytic processes based on assembled iron oxide particles

A facile magnetic control system was designed in bioelectrocatalytic process based on functionalized iron oxide particles. The iron oxide particles were modified with glucose oxidase, and ferrocene dicarboxylic acid was used as electron transfer mediator. Functionalized iron oxide particles can assemble along the direction of applied magnetic field, and the directional dependence of the assembled iron oxide particles can be utilized for device purposes. We report here how such functionalized magnetic particles are used to modulate the bioelectrocatalytic signal by changing the orientation of the applied magnetic field. (C) 2008 Elsevier B.V. All rights reserved.

硫化物的快速分光光度法测定

提出了测定微量硫化物的快速亚甲蓝分光光度法。实验结果表明：在硫酸溶液中， Ｋ２Ｃｒ２Ｏ７＋对二甲氨基苯胺＋Ｓ２－迅速显色反应形成亚甲蓝，表观摩尔吸收系数为４．０６×１０４ Ｌ·ｍｏｌ－１·ｃｍ－１；最大吸收波长为 ６６４ ｎｍ；线性范围为 ０～０．８ ｍｇ／Ｌ。实验了采用全差示光 度法直接测定水中硫化物的条件，用于某江水中２１．６ μｇ／Ｌ的硫化物测定时，相对标准偏差 为３．２％（ｎ＝６）；试样的标准加入回收率为９５％～１１０％。