高效液相色谱分析银杏叶提取物中总黄酮甙

将银杏叶提取物经酸水解得到其中黄酮甙元槲皮素、山萘酚和异鼠李素，采用高效液相色谱、ＹＷＧ－Ｃ１８柱，甲醇：水（含０４％磷酸）为流动相，ＵＶ３６０ｎｍ检测，以槲皮素为对照品计算出银杏叶提取物中总黄酮甙含量。槲皮素浓度在００１～０２ｍｇ／ｍｌ之间，浓度与峰面积呈直线关系，相关系数为０９９９２，回收率为９７４％，相对标准偏差１６１％。该方法简便、准确，易于银杏叶提取物的质量控制。     

液相色谱法测定乳粉中13种邻苯二甲酸酯

本文建立了可用于婴幼儿配方乳粉中13种邻苯二甲酸酯类环境激素测定的超高效液相色谱－二极管阵列紫外检测器分析方法．样品经甲醇饱和正己烷超声提取、柱分离富集与净化后，以乙腈和水为流动相进行梯度洗脱．所检测的13种邻苯二甲酸酯的线性范围为0．5－50 mg／L，检测下限在0．05－0．4 mg／L之间，加标回收率为92－102％，相对标准偏差均小于10％，该方法操作简便、分析时间短、灵敏度高，适用于婴幼儿配方乳粉中邻苯二甲酸酯的筛查分析．     

微波辅助萃取-高效液相色谱法测定土壤中多环芳烃

建立了用微波辅助萃取-高效液相色谱测定土壤中16种多环芳烃的方法．对萃取剂的种类,萃取方式以及微波条件进行了优化．该方法线性范围宽,检测限为0．16～11．2μg／L,相对标准偏差在1．63％～6．51％之间,加标回收率在61．3％～129．2％之间．结果表明,该方法用于测定土壤中的多环芳烃具有简便、灵敏度高和重复性好等优点,是一个有实用价值的检测方法。     

广州地区1995—1997年HIV抗体检测情况分析

为了解献血员人群ＨＩＶ感染情况，我们对１９９５～１９９７年献血员ＨＩＶ抗体检测情况进行了分析。方法：献血员ＨＩＶ抗体的初筛试验采用抗－ＨＩＶ抗体ＥＬＩＳＡ法，ＨＩＶ抗体初筛试验阳性者用蛋白印迹法（ＷＢ）进行确认。结果：３年内共检测１４００２８人次，初筛ＨＩＶ抗体阳性１８例献血员，并全部经ＷＢ法确认为ＨＩＶ抗体阳性。其中１５例为男性，３例女性，均为来自外省的流动人口。１８例ＨＩＶ抗体阳性献血员中，ＨＣＶ抗体阳性检出率为８３３％（１５／１８），ＨＢｓＡｇ阳性检出率为６１１％（１１／１８），ＨＢｓＡｇ和ＨＣＶ抗体阳性检出率为３３３％（６／８）。结论：在献血员人群中ＨＩＶ抗体阳性检出率呈上升趋势，为此献血员ＨＩＶ抗体筛查对预防和控制输血传播ＨＩＶ具有重要意义。ＨＩＶ与ＨＢＶ和ＨＣＶ具有较高的重叠感染率     

高效液相色谱法测定烟草中的淀粉含量

研究了用高效液相色谱法测定烟草中的淀粉含量，方法检测限为3．0mg／L，相对标准偏差为1．6-2．1％，标准回收率在95～105％之间。新方法用于几种烟草样品中淀粉含量测定，结果令人满意。     

高效液相色谱——高灵敏催化光度法测定钛

在１００℃稀硝酸介质中及活化关吡啶存在的条件下，痕量钛（ＩＶ）对过氧化物氢氧化甲基橙褪色这一缓慢反应具有很强的催化作用用自来水冷却中止反应，采用高效液相色谱检测甲基橙浓度的变化，建立了一个新测量０．８ｎｇ／ｍＬ～６０ｎｇ／ｍＬ钛的高效液相色谱新方法，并用于试样分析。     

东莨菪碱PVC膜离子选择性电极的研究

用氢溴酸东莨菪碱－ 四苯硼离子缔合物为电活性物质,以邻苯二甲酸二丁酯为增塑剂,研制成 Ｐ Ｖ Ｃ为基质膜的东莨菪碱离子选择性电极。东莨菪碱浓度在１０×１０－ ４ｍ ｏｌ／ Ｌ～１０×１０－ ２ｍ ｏｌ／ Ｌ时,电极电位服从能斯特方程式, 响应斜率为５９０７ ｍ Ｖ／△ｐｃ, 检测下限为７９４×１０－ ５ ｍ ｏｌ／ Ｌ, 对东莨菪碱的回收率为９７９％ ～１０９２％ , 变异系数为０４５％ 。本文考察了电极的各种性能, 测定了２０种常见离子选择性系数。方法用于实际样品中东莨菪碱的测定, 与药典标准方法比较, 相对误差２８２％ , 结果满意     

高效液相色谱法测定玉米样品中的柄曲霉毒素

本文研究了应用高效液相色谱法测定玉米样品中痕量柄曲霉毒素的新方法。样品先用甲醇：水（１：１）浸取，环已烷除油脂．再用二氯甲烷萃取毒素，然后将二氯甲烷在真空中蒸发至干，用乙腈溶解器内壁残留物并定容供分析用。柄曲霉毒素的乙腈溶液用反相色谱系统分离，乙腈／水（５５／４５，Ｖ／Ｖ）作流动相，紫外检测器检测（λ＝３２５ｎｍ），检出限ｌｐｍｏ１，回收率７６．５％。     

大鼠脑组织腺苷含量的HPLC分析

用高效液相色谱（ＨＰＬＣ）配紫外检测器，分离测定大鼠脑组织中腺苷含量。经实验确定以甲醇（１０％～６２％）、磷酸缓冲液（９０％～３８％）为流动相梯度洗脱，样品液中腺苷含量在２ｍｇ／Ｌ～１０ｍｇ／Ｌ范围内线性关系良好。加入标准样品的平均回收率为（９６６±２０）％。对６ｍｇ／Ｌ样品１０次重复测定结果的标准偏差为０１４，变异系数为３１％。对大鼠脑组织样品测定结果发现：与３～６月龄成龄鼠比较，１８～２０月龄老龄大鼠大脑皮层、海马、纹状体中腺苷含量分别增加了６６７％、３７２％和２７３％，不同脑区腺苷含量也有明显差异。结果提示不同脑区腺苷含量的随龄增加可作为研究衰老的一项指标；而中枢神经系统中随龄增长腺苷的堆积使Ａｃｈ释放受到抑制可能是出现记忆衰退等常见老年性功能障碍的一个重要原因     

双波长高效液相色谱法测定饲料的VE和VD

研究了用双波长高效液相色谱法检测饲料中Ｖ＿Ｅ和Ｖ＿Ｄ含量，采用两个波长下峰高比和保留时间相结合进行测定，提高了检测结果的可靠性，平均回收率Ｖ＿Ｅ为８９．３％，Ｖ＿Ｄ为８５％，测定变异性Ｖ＿Ｅ为２．９％，Ｖ＿Ｄ为１．４％。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.