乙腈

Methods: The analytical column was SHIMADZU VP-ODS C18 column(4.6 mm×150 mm, 5 μm) with a mobile phase consisted of 0.05 mol/L disodium hydrogen phosphate solution(85% phosphoric acid solution with pH adjustment to 2.5)-acetonitrile-methanol(42.5∶47.5∶10) at the flow rate of 1.0 ml/min, the detection wavelength was set at 254 nm.

色谱柱为SHIMADZU VP-ODS C18柱(4.6 mm×150 mm，5 μm)，流动相为0.05 mol/L磷酸氢二钠溶液(用85%磷酸溶液调节pH值至2.5)-乙腈-甲醇(42.5∶47.5∶10)，流速为1.0 ml/min，检测波长为254 nm。

Methods: The analytical column was SHIMADZU VP-ODS C18 column(4.6 mm×150 mm 5 μm) with a mobile phase consisted of 0.05 mol/L disodium hydrogen phosphate solution(85% phosphoric acid solution with pH adjustment to 2.5)-acetonitrile-methanol(42.5∶47.5∶10) at the flow rate of 1.0 ml/min the detection wavelength was set at 254 nm.

目的：建立丙酸氯倍他索尿素乳膏中丙酸氯倍他索含量的HPLC测定方法。方法：色谱柱为SHIMADZU VP-ODS C18柱(4.6 mm×150 mm5 μm)流动相为0.05 mol/L磷酸氢二钠溶液(用85%磷酸溶液调节pH值至2.5)-乙腈-甲醇(42.5∶47.5∶10)流速为1.0 ml/min 检测波长为254 nm。

Methods 7 kinds of antibiotics, dexamethasone phosphate disodium salt and salicylic acid were separated on a C18 column using methanol: acetonitrile-aqueous solutions:0.01mol/L oxalic acid=l1:22:67 as the mobile phase at a flow rate of 0.8ml/min, with the column temperature 25℃ and detection wave 240nm and 268nm.

采用C18色谱柱(4.6mm×250mm， 5μm)，以甲醇：乙腈：0.01mol/L草酸＝11：22：67为流动相，流速为0.8ml/min，检测波长为240和268nm，柱温为25℃，在此色谱条件下进行检测。

Influences of solvent/oil ratio,dilluent content and temperature on desulfurization and distribution coefficient were investigated.

以乙腈为萃取剂，在正辛烷中加入少量噻吩构成汽油模拟体系，考察了稀释剂含量、剂油比、温度对脱硫率和分配系数的影响。

The reaction of polyfluoroalkyl iodides with 4-pentenoic acids in the presence of sodium dithionite at room temperature in aqueous acetonitrile solution [CH〓CN: H〓O=3: 1 ] to gave the corresponding adducts, the latter could form γ-lactones 31～51 in the same medium in 62～92％ yield.

室温下，在乙腈/水[3：1]的介质中，多氟烷基碘化物在连二亚硫酸钠的存在下与4-戊烯酸及其在2或3位上具有取代基团的衍生物进行反应，反应2～5h，起先生成两者的加成物，该加成物无需分离，在同一介质中，可进一步反应得到相应的多氟烷基取代的γ-丁内酯31～51，产率62％～92％。

By the studies of nanosecond flash photolysis and estimates of excited state energy level, we deduce that there is a charge-transfer excited state corresponding to the transfer of an electron from the zinc porphyrin to the Ru-based moiety of 5-Zn in acetonitrile when exciting at λ= 532 nm.

纳秒闪光光解的研究和激发态的能级估算表明在乙腈溶液中，用波长532nm的激光激发5-Zn，可以形成一个电荷分离态，它对应于锌卟啉到联吡啶钌的电子转移过程，这个电荷分离态表示为：PZn~+-Ru~+。

Methods: Determining paeoniflorin content by high performance liquid chromatography measurement conditions: mobile phase of acetonitrile -0.4% phosphoric acid solution (volume ratio 13∶87; detection wavelength 230 nm; flow rate 1.0 mL/min; and column temperature 25℃; and determining polysaccharide content by anthrone-sulfuric acid method. The extraction procedure of Langchuangling granule was measured, and the evaluated indexes were the rate of dry extra, contents of the paeoniflorin and the total polysaccharide with L9 (34) orthogonal test and preferential treatment of data.

采用高效液相色谱（high performance liquid chromatography，HPLC）法测定芍药苷含量［测定条件：流动相为乙腈-0.4%的磷酸水溶液（体积比为13∶87）；检测波长230 nm；流速1.0 mL/min；柱温25℃］；采用硫酸-蒽酮法测定总多糖含量，并以干浸膏得率、总多糖含量和芍药苷含量为指标，采用L9（34）正交实验，用综合评分法处理数据优选水提取工艺。

The factors included the type of extractant, the amount and the extraction times, the type of purified column, the type and dosage of eluviatant about the pre-treatment of the samples. The extraction was 3 minutes (13500rpm) of high speed homogenize extraction. 50mL acetonitrile as an extractant was acted on one time extraction. The florin silicon column was taken as the purified column. The extraction was eluted by 30ml 3:2 acetone - hexane and concentrated by nitrogen blowing under 50 °C water bath.The chromatographic separated conditions were studied applied the Agilent 6890 gas chromatographic apparatus and DB-17 capillary column(30m×0.25mm×0.25μm).

研究了提取剂种类、用量与提取次数，净化柱种类，淋洗剂种类与用量，提取方式与提取时间，柱温和柱流量等因素对油菜籽中有机磷农药残留提取、分离净化和色谱分离的影响，建立了采用高速匀浆提取方式提取3min13500rpm.min~(-1，以50mL乙腈为提取剂一次提取，以弗罗里硅柱为样品液净化柱，以30mL 3：2丙酮-正己烷为淋洗剂，在50℃水浴条件下用氮吹浓缩，气相色谱检测的油菜籽有机磷农药多种残留检测技术。

Methods: It was used with acetonitrile-0.5%phosphoric acid solution(42∶58) as a mobile phase by HPLC. The detecting wavelength was 266nm. The flow rate was 1.0 mLmin^(-1). Results: When Gaoliangjian and Xiangfu are extracted together by alcohol, the content of galangin is the highest.

采用HPLC法，以乙腈-0.5%磷酸(42：58)为流动相，检测波长：266nm，流速：1.0mlmin^(-1)；结果：高良姜与香附的提取方法为乙醇合并提取时，高良姜素的含量高于其他提取方法。

HPLC was used to determine harmine concentration in the oral emulsion or in tissues of mice. Stationary phase: Shim pack CLC ODS column; mobile phase: acetonitribe methanol phosphate buffer (pH6.8)(30∶30∶40); mobile speed: 1.0 mL/min; detection wavelength: 300 nm; column temperature: 20℃.

采用高效液相色谱法测定口服乳剂中的harmine含量和各脏器组织中的药物浓度；色谱柱Shim pack CLC ODS柱，流动相为ψ［乙腈∶甲醇∶磷酸盐缓冲液（pH6.8）］=30∶30∶40，流速1.0 mL/min，检测波长300 nm，柱温为室温。

Now, however, all children continue in "comprehensive" schools, and the eleven-plus determines which courses of study the child will follow.

然而现在，所有的孩子都要在综合学校继续学习，所以这次考试只是决定他们将要学习哪些课程。

Cultivatable land , and led to a general recognition that development must not be carried at the cost of agriculture .

城区的迅速扩大在很多情况下侵占了宝贵的可耕地，使人们普遍认识到发展不能以牺牲农业为代价。