HPLC检测鳗鱼中部分氟喹诺酮类药物残留

建立了高效液相色谱法检测鳗鱼中恩诺沙星、环丙沙星、诺氟沙星等合成抗菌剂残留的方法。样品以乙腈为提取剂,经脱脂、净化、浓缩,用流动相溶解。用高效液相色谱荧光检测器测定恩诺沙星、环丙沙星、诺氟沙星。各标准曲线线性范围0．05—1．20μg／ml,线性相关系数r=0．9911—0．9943,实验回收率为55．0％～85．9％,RSD在5．58％～7．38％（n=5）,检坝4低限分别为1μg／kg,2μg／kg,2μg／kg。     

催化溴酸钾氧化吖啶橙褪色光度法测定痕量Cr（Ⅵ）

基于H2SO4介质中,沸水浴加热10min的条件下,铬（Ⅵ）能显著催化溴酸钾氧化吖啶橙（R）的褪色反应,据此建立了催化溴酸钾氧化吖啶橙褪色光度法测定痕量Cr（Ⅵ）的新方法．其线性范围为0．02—0．40μg／L,工作曲线的回归方程为△A=0．07684＋0．14971CCr（Ⅵ）（μg／L）,相关系数r=0．9966,检出限为1．1×10^-11g／mL．本法成功用于江水、人发中的痕量铬（Ⅵ）的测定,结果满意．     

固相萃取-UPLC—MS／MS测定食品中的黄曲霉毒素M1和B1

建立固相萃取与UPLC—MS／MS检测食品中黄曲霉毒素M1和黄曲霉毒素B1的方法。样品经乙腈提取和SPE小柱萃取净化,提取液经氮气吹干后,用50％甲醇水溶液定容。超高效液相色谱一串联质谱（UPLC—MS／MS）测定,采用电喷雾正离子（ESI＋）模式电离,多反应监测（MRM）模式检测。流动相为0．1％甲酸水溶液和甲醇,流速0．4ml／min,使用ZORBAX Eclipse XDB—C18色谱柱（100mm×3．0mm×1．8μm）为分析柱。黄曲霉毒素AFM1在0．1～50μg／kg范围内线性关系良好、黄曲霉毒素AFB1在0．1～10ug／kg范围内线性关系良好,相关系数均大于0．999;回收率在83．75％～97．8％之间;检出限AFMl为0．05μg／kg、AFBl0．02μg／kg。该法具有分析速度快,检测准确、灵敏度和回收率高等优点,适合食品中黄曲霉毒素M1、B1含量的检测。     

微波消解电感耦合等到离子发射光谱法测定化妆品中微量元素

采用HNO3-H2O2的微波消解ICP-AES法测定乳状化妆品中As、Pb、Cd、Cr、Bi五种微量元素、方法的相对标准偏差(RSD)：O．94-3．1％，回收率：86．7-107．8％，检测限As:0．002μgml、Pb：O．004μg/ml、Bi：0．002μg/ml、Cd：O．002μgml、Cd：0．009μg/ml、Cr：0．0006μg/ml。     

联合吸人糖皮质激素和长效β2激动剂治疗COPD疗效观察

目的：探讨联合吸入糖皮质激素与长效＆激动剂对慢性阻塞性肺疾病（COPD）的治疗作用。方法：急性加重期COPD病人60例，给予吸入布地奈德干粉400μg．2次／d．同时吸入福莫特罗干粉9μg，2次／d。观察1月、3月、6月，并测定痰液中炎性介质白细胞介素（IL-8）的量。结果：肺功能治疗前后有明显提高（P〈0．05）。呼吸症状均有所改善，尤其是喘息症状改善明显；痰中IL-8治疗后明显下降（P〈O．05）。结论：联合吸入糖皮质激素与长效β2激动剂对COPD患者的肺功能、自觉症状均有改善，痰中IL-8水平降低，可能与糖皮质激素加强了对气道炎症的作用有关。     

荧光分光光度法测定头孢噻肟钠的含量

在过硫酸钾存在下的近中性介质中,头孢噻肟钠能够增强荧光桃红的荧光强度,从而建立了荧光法测定头孢噻肟钠含量的新方法。头孢噻肟钠的质量浓度与荧光强度的变化在0．6～3．0μg/mL范围内呈良好的线性关系（1=0．9984）,对浓度为1．0μg／mL的头孢噻肟钠试液连续测定11次,相对标准偏差（RSD）为1．25％,检出限为0．0376μg／mL。该法简便、快速,结果可靠,并应用于药物制剂中头孢噻肟钠含量的测定,结果令人满意。     

慈姑多糖降血糖的生物活性研究

目的：考察慈姑多糖对四氧嘧啶性糖尿病模型小鼠血糖的影响。方法：采用皮下一次性注射190mg／kg四氧嘧啶致实验性糖尿病小鼠,观察慈姑多糖不同剂量（0．75g／kg,0．375g／kg）对糖尿病小鼠空腹血糖的影响。结果：慈姑多糖高、低剂量组能显著性降低血糖水平（P〈0．05）。结论：慈姑多糖具有一定的降血糖作用。     

高效液相色谱法同时测定美白类化妆品中熊果苷和氢醌的含量

探讨了高效液相色谱法同时测定关白化妆品中熊果苷和氢醌含量的方法,先对样品进行预处理,处理液为氯仿-饱和氯化钠溶液（体积比2：1）,再选用ApolloC18柱,以甲醇-磷酸缓冲液-冰醋酸（体积比25475：1）混合液为流动相,紫外检测,波长为254nm。实验结果表明,该方法在0．01～0.2g/L时具有良好的线性;平均回收率范围为97％～98．5％;熊果苷的检出限为21μg／kg,氢醌的检出限24μg／kg。     

Ce(Ⅳ)-罗丹明6G化学发光体系快速测定染料木素

在硝酸介质中,Ce（SO4）2氧化染料木素,罗丹明6G可以增强其化学发光强度．据此采用流动注射技术,建立了Ce（Ⅳ）-罗丹明6G-染料木素化学发光体系测定染料木素的化学发光新方法．在优化的实验条件下,该法测定染料木素的检出限为0．4μg／L,线性范围为0．0025．000μg／mL,对0．5μg／mL染料木素进行了11次平行测定,其RSD为1．67％．将本法用于尿样及槐角中染料木素含量的测定获得满意结果,并对反应可能的机理进行了探讨．     

土壤金属污染源的定位研究

对某城市工业区土壤汞（Hg）、镉（Cd）、铅（Pb）、砷（As）、铜（Cu）、铬（Cr）、镍（Ni）、锌（Zn）八种重金属元素含量的数据进行统计分析,研究了它们的分布特征．定义了一个随机变量X表示采样点状态,它描述了各金属浓度在该采样点所占比例,具有分布P（X=i）=xiμg／1g=Pi．给出了自然区的熵H=-∑Pil...     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

库克斯顿城堡

城堡, 是欧洲典型的建筑之一, 每个城堡都有一个美丽的传说或是一段历史。从本期开始, 我们将推出“城堡之旅”, 带各位读者去浏览、观赏欧洲各地的城堡, 开始一段文化与历史的旅途!     

The Reader Response Approach to Teaching of English Literature

During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context.