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。     

高效液相色谱法测定土壤中的多环芳烃

采用高效液相色谱-荧光检测器快速测定土壤中15种多环芳烃。通过对液相色谱柱、梯度洗脱程序、检测波长程序及柱温等液相色谱条件的选择和优化,使土壤样品中15种多环芳烃在32min内得到完全分离,方法的最低检出限为0.0002～0.0045 mg/kg,回收率为71.20%～95.07%,RSD为5%～10%。该优化方法的精密度高、检出限低、重复性好,是一种能够快速、准确测定土壤中多环芳烃的检测方法。     

凝胶净化-固相萃取-高效液相色谱法同时测定烤肉中的16种多环芳烃

建立了烤肉中16种多环芳烃的凝胶净化-固相萃取-高效液相色谱(GPC-SPE-HPLC)的定量检测方法.样品经丙酮:正己垸(1:1)混合溶液超声30min提取.凝胶色谱和硅胶固相萃取净化,高效液相色谱配荧光检测器和紫外检测器分析.结果表明:线性关系R≥0.997.在50μg/kg添加水平各化合物的回收率为88.4%~102.1%,RSD(n=7)≤5.35 oA.检出限为0.2pg/kg~1.0μg/kg.该方法灵敏度高、重现性好,可同时检测烤内中16种PAHs.     

高效液相色谱法测定地表灰尘中的16种多环芳烃

用高效液相色谱分析方法测定了地表灰尘中16种多环芳烃.样品经超声提取、硅胶萃取柱净化后,用液相色谱测定.优化了试验条件,16种多环芳烃的检出限为0.08~4.65μg/kg,方法线性关系良好,基质加标回收率为77.6;~113.7;,相对标准偏差为1.26;~7.32;     

反相高效液相色谱法测定血浆中多沙唑嗪

采用固相萃取反相高效液相色谱法测定小鼠血浆中的多沙唑嗪．血浆样品经过C18固相萃取小柱净化后,在 YMC C18色谱柱(4．6 mm×250 mm,5μm)上,以甲醇-0．02 mol／L磷酸二氢钾溶液(体积比70:30,pH 3．0)为流动相,流速0．6 mL／min,检测波长246 nm对多沙唑嗪进行测定．实验结果表明,多沙唑嗪的血药浓度在0．2-50 μg／mL范围内与峰面积呈良好线性关系,平均回收率为99．06％,精密度为2．5％,最低检测限为0．1 μg／mL,该方法简便、快速、准确度高、可靠性好．     

超声萃取—高效液相色谱测定沉积物中的多环芳烃

用正己烷—丙酮(1∶1,体积比)混合液作溶剂,超声萃取提取沉积物中的16种多环芳烃组分.萃取液经硅胶小柱层析净化,旋转蒸发仪浓缩,最后用高效液相色谱—荧光串联紫外检测器分析,并进行加标回收测定.16种多环芳烃的检测限为0.34～1.52 ng· g-1,经精密度试验,相对标准偏差均＜15％,回收率在57.09％～103...     

高效液相色谱法检测土壤中的5种多环芳烃

建立索氏提取-高效液相色谱分离,紫外检测萘、联苯、苊、菲、蒽5种多环芳烃的分析方法,并对流动相组成、柱温、流速等色谱分离条件进行了详细的探讨,在优化的条件下,5种多环芳烃在22min内达到基线分离,检测限在0.001～0.03μg.mL-1之间.且将该方法成功地用于校园内3个地点的土壤中多环芳烃的测定.     

HPLC法测定奶粉中痕量炔雌醇

建立了高效液相色谱（HPLC）法测定奶粉中炔雌醇残留量的方法。样品以乙腈振荡萃取、离心,提取液浓缩后经O．45μm滤膜过滤,冷冻去脂,进高效液相色谱仪分析。研究了萃取溶剂、萃取及浓缩方式对萃取效率的影响,确立了色谱检测条件。乙腈-水（50：50）为流动相,流速1mL／min,柱温30℃,检测波长224nm。方法的检出限为16μg／kg,加标回收率在86．5％～97．0％之间,工作曲线的相关系数为0．9990,相对标准偏差为0．95％～2．01％（n=3）。方法快速、灵敏度高、分离效果好,样品处理简单、无杂质干扰,能够满足奶粉中雌激素分析的需要。     

固相萃取-高效液相色谱-二极管阵列检测法测定原料乳中三聚氰胺

原料乳经三氯乙酸和乙腈提取,高速离心后取上清液,用阳离子交换固相萃取小柱净化后,以乙腈一庚烷磺酸钠缓冲液作流动相,采用AgilemZorbax300-SCX250×4．6mm色谱柱分离,高效液相色谱一二极管阵列检测器（HPLC-DAD）,外标法定量。方法线性范围0．005-5．00gg／mL,相关系数r〉0．9999,加标回收率为103．6％-105．2％,RSD为O．26％,保留时间在6．82min左右,检出限为O．5mg／kg。该方法简单、快速,适用于大批量样品的快速检验和乳制品出厂检验。     

高效液相色谱法测定花生中黄曲霉素的含量

目的测出黄曲霉素在花生中的含量。方法采用高效液相谱（HPLC）法，使用Agilent1100色谱柱；在柱温30℃；乙腈-甲醇-水（1：1：2）为流动相；流速为1．0ml／min；荧光检测器；激发波长为360nm；发射波长为450nm的条件下测定。待测物经甲醇萃取及免疫亲合柱提取，内标法峰面积定量。结果黄曲霉素的色谱响应线性关系良好，方法重复性的RSD为0．38％，平均回收率为78．4％。结论该方法专属性强，灵敏度高，精密度和准确度好。     

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.