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排序方式: 共有472条查询结果,搜索用时 31 毫秒
1.
Xiaoshuang Luo Xinxian Qin Zhengyi Liu Dan Chen Weiwei Yu Kankan Zhang Deyu Hu 《Biomedical chromatography : BMC》2020,34(1):e4694
A simple and rapid analytical method for the detection of trifloxystrobin, trifloxystrobin acid and tebuconazole in soil, brown rice, paddy plants and rice hulls was established and validated by liquid chromatography with tandem mass spectrometry. Acceptable linearity (R2 > 0.99), accuracy (average recoveries of 74.3–108.5%) and precision (intra- and inter-day relative standard deviations of 0.9–8.8%) were obtained using the developed determination approach. In the field trial, the half-lives of trifloxystrobin and tebuconazole in paddy plants were 5.7–8.3 days in three locations throughout China, and the terminal residue concentrations of trifloxystrobin and tebuconazole were <100 and 500 μg/kg (maximum residue limits set by China), respectively, at harvest, which indicated that, based on the recommended application procedure, trifloxystrobin and tebuconazole are safe for use on rice. The risk assessment results demonstrated that, owing to risk quotient values of both fungicides being <100%, the potential risk of trifloxystrobin and tebuconazole on rice was acceptable for Chinese consumers. These data could provide supporting information for the proper use and safety evaluation of trifloxystrobin and tebuconazole in rice. 相似文献
2.
通过筛选水稻开花后48~50h的原胚和120~122h的分化胚的cDNA文库,得到一个在胚胎发育过程中表达有差异的克隆,命名为OsEES,测序结果显示OsEES含有一个预测的亚精氨合成酶结构域,编码一个大小约38×103(pI6.5)的蛋白.同时RNA原位杂交的结果显示开花48~50h的原胚中的信号强度明显大于开花120~122h的分化胚,表明OsEES可能在水稻胚胎发生过程中起到一定的调控作用. 相似文献
3.
研究了原子化器温度、载气流速、KBH4 浓度等条件对流动注射 氢化物发生 原子吸收光谱法 (FI-HG -AAS)测定硒时的影响。建立了FI-HG -AAS测定大米中硒的分析方法。在优化的工作条件下 ,测定硒的最低检测浓度为 0 3 3 μg·L- 1,线性范围为 0~ 5 0 μg·L- 1,相对标准偏差小于 4% ,加标回收率为 94%~ 1 0 2 %。本法克服了传统的间断氢化物发生 原子吸收光谱法分析速度慢、样品耗量大、操作繁琐且因手工进样在进样速度和进样体积上容易带来误差等缺点。方法操作简便、快速 ,灵敏度及自动化程度高 ,已广泛应用于大米及富硒大米中微量硒的测定 相似文献
4.
三十烷醇在GA_3影响水稻幼苗生长和生理性状中的增效作用 总被引:2,自引:0,他引:2
微量三十烷醇(TRIA)与GA3配合使用,比GA3单独使用能明显地促进幼苗生长和增加幼苗干物质积累.同时还增强了GA3对幼叶中叶绿素含量、可溶性蛋白质含量、呼吸速率、细胞膜透性和过氧化物酶活性的影响.GA3+TRIA与GA3处理相比,促进幼叶内源GA3水平提高,稳定保持内源ZT于一定水平,TRIA在GA3低浓度时降低IAA水平,在高浓度时则提高IAA水平.作者认为TRIA可作为GA3处理时的增效剂. 相似文献
5.
钙黄绿素蓝荧光法测定食品中的微量锌(Ⅱ) 总被引:5,自引:0,他引:5
本文研究了在CTMAB存在下,用钙黄绿素蓝荧光法测定食品中的微量锌(Ⅱ)的实验条件。在本实验条件下,Zn(Ⅱ)与钙黄绿素蓝生成1:1的配合物使钙黄绿素蓝的荧光增强,最大激发波长和最大发射波长分别为353nm和440nm。 相似文献
6.
高效液相色谱法测定糙米粉中的维生素 总被引:7,自引:1,他引:7
高效液相色谱法测定糙米粉中的维生素吴红京,唐根源,王勇(中国科学院福建物质结构研究所福州350002)(福建药品检验所福州350001)1前言众所周知,糙米粉有很高的营养价值,含有人体必需的多种维生素。用高效液相色谱法(HPLC)和薄层色谱法(TLC... 相似文献
7.
C. C. Seow C. H. Teo C. K. Vasanti Nair 《Journal of Thermal Analysis and Calorimetry》1996,47(5):1201-1212
Thermal characterization of gelatinized binary rice starch-water and ternary starch-sugar-water gels before and after aging was carried out using differential scanning calorimetry. The glass transition temperature of the maximally freeze-concentrated solution (Tg) in both fresh and aged gels was observed to decrease progressively with increasing sugar concentration. Aging of the gels generally shiftedTg to higher temperatures, but had little or no effect on the ice melting peak temperature (T
m). The presence of various sugars could either accelerate or retard starch (amylopectin) recrystallization, depending on the type and concentration of sugar, as well as on starch/water ratio. A hypothesis based on the dual antiplasticizing-plasticizing effects of sugars was postulated to explain the observed effects. Of the sugars studied, xylose and fructose appeared to display exceptional retardative and accelerative effects, respectively, on retrogradation.This study was funded by a Sixth Malaysia Plan R&D grant under the Intensification of Research Priority Areas (IRPA) Program of the Ministry of Science, Technology and Environment, Malaysia. We thank Dr. Harry Levine and Dr. Louise Slade for giving us the opportunity to contribute a paper to this special issue of JTA. 相似文献
8.
二阶导数卷积伏安法应用于水稻中痛量雌雄激素的检测,具有快速,灵敏,干扰少的特点。本文以光周期敏感核不育水稻农垦58S为材料,以农垦58作对照,了叶焉和穗中雌,雄性激素的含量,研究了不同光周期条件下两类激素的变化。 相似文献
9.
Alejandro Colina Betzabé Sulbarán-de-Ferrer Cateryna Aiello Alexis Ferrer 《Applied biochemistry and biotechnology》2003,108(1-3):715-724
Xylanase production of Trichoderma reesei Rut C-30 was examined at different initial pH values (4.8, 5.9, and 7.0) on rice straw in shake flasks, and in a fermentor,
for the best pH condition. Enzyme performance was tested on ammonia-treated dwarf elephant grass. The maximum xylanase activities,
92 and 122 IU/mL, were obtained at pH 4.8 in the shake flasks and fermentor, respectively, in which good growth of the fungus
was observed during the first 24 h and consumption of proteins dissolved from the rice straw caused the pH to rise later to
values between 6.4 and 6.7 (optimal for xylanase production). The xylanases from T. reesei were as effective as Multifect XL, a commercial enzyme preparation, in hydrolyzing ammonia-treated elephant grass. 相似文献
10.
I. M. Chung Mohd Ali A. Ahmad C. Y. Yu K. H. Ma J. G. Gwag Y. J. Park 《Chemistry of Natural Compounds》2005,41(6):650-653
One new compound 3,7,11,15,19-pentamethyl-9α,10α,11α,17α,18α-pentahydroxy-n-tetracosan-1-oxy-p-hydroxycaffeoate (oryzaterpenyl
caffeoate) (1), together with three known fatty acids linoleic acid, stearic acid and myristic acid were isolated and identified from the
rice grain of Oryza sativa. The structure of the new compound was elucidated by 1D and 2D NMR spectroscopic techniques (1H-1HCOSY, 1H-13C HETCOR) aided by EI-MS, and IR spectra.
__________
Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 535–537, November–December, 2005. 相似文献