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Search Results: 1 - 10 of 321051 matches for " <br>黄百芬 "
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Simultaneous determination of 7 female sex hormones in essential oil by high performance liquid chromatography- tandem mass spectrometry with isotope dilution
同位素稀释-超高效液相色谱-串联质谱法同时测定精油中的7种雌性激素

HUANG Baifen,HAN Zheng,XU Xiaomin,CAI Zengxuan,JIANG Wei,REN Yiping,<br>,韩铮,徐小民,蔡增轩,姜维,任一平
色谱 , 2011,
Abstract: A reliable ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous determination of 7 female sex hormones (estriol, estradiol, estrone, ethinyloestradiol, dienestrol, hexestrol, diethylstilbestrol) in essential oil was developed. The sample was extracted by ethylacetate-normal hexane solution (2:98, v/v) and the extract was purified by a silica solid phase extraction-based clean-up column. Then, the analytes were separated on an ACQUITY UPLC BEH SHELD RP18 column (100 mm×2.1 mm, 1.7 μm) in gradient elution with the mobile phases of water and acetonitrile. The separated compounds were detected with a Waters Xevo TQ MS tandem quadrupole mass spectrometer operated in negative electro-spray ionization using multiple reaction monitoring mode. Estriol-D3, estradiol-D3 and diethylstilbestrol-D6 were used as the internal standards to reduce the matrix effects. The limits of detection and quantitation for the 7 female sex hormones in essential oil were 0.3~7 μg/kg and 1~20 μg/kg, respectively. Good linear relationships and high correlation coefficients (r2≥0.997) were obtained in the mass concentration range of 20~500 μg/L. The average recoveries were 88.5%~114.8% and the intra-assay relative standard deviations were 4.8%~18.9% at the spiked levels of 20~500 μg/kg. Finally, a total of 12 samples randomly collected from different supermarkets in Zhejiang Province were screened for the 7 female sex hormones by the proposed method. The results showed that only one sample contained estradiol and estrone.
高效液相色谱法同时测定果蔬与血浆中的番茄红素和β-胡萝卜素
李向荣,方晓,陈青俊,
浙江大学学报(农业与生命科学版) , 2000,
Abstract: 为了建立一种快速分离和分析果蔬食物与血浆中番茄红素和β-胡萝卜素的方法,对不同样品采用不同的前处理:以ODS-C18为色谱柱,乙腈:四氢呋喃(60:40,V/V)为流动相,在1.0mL/min的流速下,选择445nm检测。番茄红素和β-胡萝卜素的回收率分别为89.54% ̄93.71%和90.29% ̄96.43%,变异系数为3.9% ̄5.68%。番茄红素和β-胡萝卜素能很好地分离。高效液相色谱法简单
THE CHARACTERIZATION FOR REGULAR LANGUAGES
正则语言的特征性质

Ye Ruifen,Shen Baiying,<br>叶瑞,
软件学报 , 1995,
Abstract: Common pumping lemma for regular languages characterizes the necessary condition that a language is regular. This paper gives several necessary and sufficient conditions and common pumping lemma and generalized pumping lemma are obtained as their consequence.
柱后光化学衍生荧光检测高效液相色谱法测定食品中的维生素B1
任一平,陈恒武,陈青俊,包敛彬,,何巧红
分析化学 , 2000,
Abstract: 研究柱后光化学衍生荧光检测高效液相色谱分离测定食品中维生素B1的方法。采用C18柱,以含有2%乙腈的pH4.0磷酸盐缓冲液(0.1mol/L)作流动相反相分离,猪肝等食品中的维生素B1可与其它杂质达到完全分离。色谱流出液在柱后与0.75%Na2SO3-4%NaOH的混合试剂溶液在线汇合后流经一聚四氟乙烯(PTFE)细管制成的光化学反应器时,维生素B1转化为强荧光产物,由荧光检测器测定。在最佳条件下,进样20μL检测限为3.8μg/L,工作曲线的线性范围为0.033-10mg/L,相对标准偏差(RSD)为1.8%,标准加入回收率为97%-102%。所建立的方法用于鲜猪肝和奶粉中维生素B1的测定,取得了满意的结果。
The Structure of Chlorophyll-Protein Complexes of Algal PSI and the Characteristics of Their Long-Wavel ength Fluorescence
藻类光合作用PSI色素蛋白复合物结构及长波荧光特性

CHEN Min,LI Ai-Fen,ZHOU Bai-Cheng,<br>陈敏,李爱,
植物学报 , 1999,
Abstract: Studies on the structure of chlorophyll-protein complexes of algal PSI and the characteristics of their long-wavelength fluorescence are reviewed, and comparied with those of higher plants. The diversity of algal PSI forms a sharp contrast with the identity of PSI of higher plants, and has the characteristics of phylumla. Comparitive studies between the. PSI of algae and higher plants will contribute a better under standing to the structure, function and evolution of PSI.
Advances and Problems in Studies of Photosynthetic Pigment-Protein Complexes of Brown Algae
褐藻光合作用色素—蛋白质复合物——研究进展和问题

LI Al-Fen,CHEN Min amd ZHOU Bai-Cheng,<br>李爱,陈敏,
植物学报 , 1999,
Abstract: 本文综述了近二十年来褐藻色素-蛋白质复合物的研究进展,包括色素—蛋白质复合物分离技术、褐藻的光系统Ⅰ、光系统Ⅱ及捕光色素—蛋白质复合物研究进展。并就褐藻色素—蛋白质复合物分离技术中存在的问题、褐藻的特点、褐藻与其它光合生物的色素—蛋白质复合物的同源性以及褐藻PSI复合物77 K荧光发射的特点等进行了讨论。
Studies on Characterization of Fluorescence Emission Spectra of Brown Algae at 77K
褐藻77 K荧光特异性研究

LI AI-Fen,CHEN Min,ZHOU Bai-Cheng,<br>李爱,陈敏,
植物学报 , 1999,
Abstract: 测定了裙带菜、叉开网地藻、海带、囊藻、海蒿子、鼠尾藻、萱藻和水云等8种褐藻的77K荧光光谱并同菠菜和红藻条斑紫菜作了比较。结果表明与红藻和高等植物明显不同,褐藻没有作为PSⅠ特征的730 nm荧光峰。按荧光主峰的波长,可以分为二种类型:裙带菜、叉开网地藻、海带和囊藻的荧光主峰位于690 nm,海蒿子、萱藻、水云和鼠尾藻的荧光主峰在705-720 nm。这种77K荧光特异性预示褐藻同高等植物之间在PSⅠ结构上的差异。
改善式BVEDA求解多目标调度问题
Improved bi-variables estimation of distribution algorithms for multi-objective permutation flow shop scheduling problem

裴小兵,陈慧,,陈孟辉<br>PEI Xiaobing, CHEN Huifen, ZHANG Baizhan, CHEN Menghui
- , 2017, DOI: 10.6040/j.issn.1672-3961.0.2016.256
Abstract: 摘要: 针对以最小化最大完工时间、最小化最大拖期和最小化总流程时间为目标的置换流水车间调度问题(permutation flow shop scheduling problem, PFSP),基于双变量分布估计法(bi-variable estimation of distribution algorithm, BVEDA)提出改善式双变量分布估计算法(Improved BVEDA, IBVEDA)进行求解。利用BVEDA中双变量概率模型进行区块构建,根据组合概率公式进行区块竞争和区块挖掘,借用高质量的区块组合人造解,提高演化过程中解的质量;针对算法多样性较差的特点,设计在组合人造解的过程中加入派工规则最短处理时间、最长处理时间和最早交货期,将上述方法并行演化,通过top10的权重适度值总和动态调整上述方法处理的解的数量,最后利用帕累托支配筛选和保存非支配解。试验使用C++代码在Taillard标准算例上测试,IBVEDA与SPGAⅡ和BVEDA比较,并绘制解的分布图证实算法的有效性。
Abstract: Aiming at permutation flow shop scheduling problem(PFSP)with the minimum maximum makespan, the minimum maximum tardiness and the minimum total flow time as objectives, improved bi-variable estimation of distribution algorithm(IBVEDA)based on bi-variables estimation of distribution algorithm(BVEDA)was proposed. Building blocks was designed using bi-variable probability model of IBVEDA, according to combination probability formula for block competition and block mining, then artificial chromosomes were generated using high quality blocks to improve the quality of solution in the evolution process. To enhance the diversity of algorithm, dispatching rules, the shortest processing time, longest processing time,earliest due date were added in parallel evolution while injecting artificial chromosomes, the number of individual for next iteration processed by the methods above depended on the above methods top 10 total weighted fitness of last iteration to do dynamic adjustment, finally Pareto dominance was used to select and save non-dominated solutions. The experiment used C++ code tested on Taillards standard instances, IBVEDA was compared with SPGAⅡand BVEDA and solution distribution of the three algorithms were plot which the effectiveness of IBVEDA was validated
nfluencing factors analysis of willingness to pay for ecosystem services evaluation of Hongze Lake
湖泊生态系统服务功能支付意愿的影响因素——以洪泽湖为例

Huangl Lei,<br>,,袁增伟,田丰,毕军
生态学报 , 2010,
Abstract: 为更好的保护湖泊生态系统,同时为了提供湖泊生态安全管理、宣传、预防等方面的建议,应用目前评价非使用价值较成熟的条件价值法(CVM),以洪泽湖为研究对象,采用实地调研的方式,运用支付意愿问卷调查的形式,结合数据相关分析和回归分析的方法,分析了湖泊生态系统服务功能支付意愿的影响因素。共发放支付卡式CVM问卷520份,回收有效问卷498份,获得支付意愿的分布形态和规律。运用Logit回归模型分析湖泊生态服务功能价值评估过程中的主要影响因素,对比分析了不同人群对恢复该湖泊生态服务功能支付意愿的差异。通过多元统计分析得到在洪泽湖生态系统恢复计划案例中,受访者的支付意愿主要受到家庭年收入、对政府的信任程度和对环境保护的意识等因素的影响,并展开了较为详细的讨论和解释。最后针对模型分析的结果,提出具体可行的增强公众环保态度和环保意愿的建议,为政府相关政策的制定提供理论基础,为决策者选择有效目标人群提供参考依据。
Effects of Oxygen Treatment on Interface Character istics and Composition of Nitrided-Oxide
氧处理对氮氧化膜界面特性和组分的影响

Li Guanqi/,<br>李观启,美浅,
半导体学报 , 1990,
Abstract: 实验结果表明,利用O_2 /N_2的低分压再氧化和中间氧化,以及利用O_2/NH_3的掺氧再氮化均能有效地改善氮氧化膜的界面特性,而其优异的电击穿特性则得以保持或稍有改善。在三种氧处理方法中,中间氧化的效果较显著,而掺氧再氮化则呈现较低的抗氧化能力。
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