浓度测定

In this article, the author extracted flavonoid from Hibiscus manihot L by alcohol reflux, and measure the effects of different concentration flavonoid extracts on tyrosinase activity using the Spectrophotometry.

利用乙醇回流提取法提取金花葵花中的总黄酮，采用分光光度法测定不同浓度金花葵总黄酮对酪氨酸酶活性的影响。

The activity coefficientsof HCl in mannite and water mixed solvent are measured using conductivity method,and the effect of concentration and temperature on activity coeffcients of electrolyte solutions discussed.

应用电导法测定了HCl在水和甘露醇混合溶剂中的活度系数，讨论了电解质溶液活度系数与温度和浓度的关系。

This paper takes conchocelis of Porphyra yezoensis as experiment material, analyzes the toxicity of heavy metal ions on 6 parameters of chlorophyll a content, soluble protein content, mannite content, peroxidase activity, malonaldehyde content and the growth of conchocelis. In experimental conditions, samples were exposed to mercuryHg~(2+, copperCu~(2+, cadmium Cd~(2+, plumbumPb~(2+ and zincZn~(2+ at different concentrations and were taken after exposure for different hours.

本文以条斑紫菜丝状体为实验材料，测定条斑紫菜丝状体中叶绿素a含量、可溶性蛋白含量、甘露醇含量、过氧化物酶活性、丙二醛含量及藻体生长情况6项生理生化指标，研究分析了不同处理浓度和不同培养时间下重金属离子Hg~(2+)、Cu~(2+)、Cd~(2+)、Pb~(2+)、Zn~(2+)对条斑紫菜丝状体的毒性效应。

To 6500m a.s.l.. In September 1998, an 80.36m ice core was also recovered in accumulation zone of the East Rongbuk Glacier on the northern slope of Mount Everest. The ice core was dated by seasonal variations of δ〓O (measured by Mat-Plus gas isotopic mass spectrograph with precision of 0.5‰) and major ions (measured by DX-2010 ions chromatography with precision of ng/L), together with the references of β activity peaks. Annual net accumulation was reconstructed based on the dating and density profile of the ice core.

此外，笔者还参加了1998年9月东绒布冰川80.36m冰芯的钻取工作。1999-2000年，在实验室内对上述样品进行了δ〓O测量(在中科院寒区旱区环境与工程研究所冰芯与寒区环境开放研究实验室用Mat-Plus气体稳定同位素质谱仪测量，以δ〓O平均值为-20.05‰的希夏邦马峰地区大气降水作为标准水，测量精度为0.5‰)、主要可溶性阴阳离子浓度的测定(在美国新罕布什尔大学气候变化研究中心进行，测试仪器为DX-2010型离子色谱仪，其测量精度可达ng/L)以及β活化度的测量(在美国新罕布什尔大学气候变化研究中心进行)，并以此为基础尝试重建了该冰芯的年代和净积累量。

The MBCs of ceftazidime on planktonic or sessile PA are tested. The effects of 4μg/ml azithromycin on the MBCs of ceftazidime are studied.

本研究测定头孢服啶对悬浮状态和BF中座生PA的最小浓度。

The point of zero net charge for the meadow brown soil in northeast of China with structural negative charges was measured by three methods: potentiometric titration, mass titration and inert electrolyte titration, showing that for the meadow brown soil which possesses structural negative charges, a PZNC independent of electrolyte concentration exists, and the values of pHPZNC obtained by the above three methods are 2.9, 5.0 and 3.3, respectively.

分别采用电势滴定法，质量滴定法和惰性电解质滴定法测定了荷结构负电荷的东北草甸棕壤的零净电荷点，研究表明荷结构负电荷的土壤依然存在与电解质浓度无关的零净电荷点，三种方法的实验结果分别为2.9， 5.0和3.3。

The eco-toxicity of Cu, Zn, Pb, and Cd in the single form was tested with four types of soils( red loam soils, meadow brown soils, chestnut soils, and dark brown soik) and their combined effect was determined with meadow brown soils.

测定了4种土壤(红壤、草甸棕壤、暗棕壤和栗钙土)条件下，Cu、Zn、Pb和Cd单一污染对小麦种子发芽与根伸长抑制率及其复合污染效应结果表明，同一浓度下，重金属对小麦根伸长抑制率均明显大于对种子发芽抑制率。

Methods Serum levels of creatinineand urea nitrogen,and levels of lipid peroxide,mercury,iron,calcium,zinc,copper,in the kidney of mice exposed to mercury chloride were determined.

分别测定氯化汞染毒小鼠的血清肌酐和尿素氮、肾脏脂质过氧化物值及肾脏汞、钙、铁、锌、铜等金属浓度和肾脏组织形态的变化。

While erthrocyte, hemoglobin and Hela cell were under oxidative damage induced by the hydrogen peroxide (H2O2) or tert-butyl hydroperoxide on different concentrations of dihydromyricetin, hemolysis rate of erythrocyte and methemoglobin converted from hemoglobin was estimated by ultraviolet-visible absorption spectroscopy. Whereas mmalondialdehyde from erythrocyte was measured by thiobarbituric acid colorimetry, the cellular viability of Hela cell was examined using MTT 3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyl tetrazolium bromide assay.

在不同的二氢杨梅素浓度下，用过氧化氢或过氧化特丁烷对红细胞、血红蛋白和Hela细胞进行氧化伤害，以紫外－可见光分光光度法检测红细胞溶血率和由正常血红蛋白生成的高铁血红蛋白，硫代巴比妥酸法测定红细胞中的丙二醛，MTT法检测Hela细胞的活力。

Diffusion coefficients for metol and p-benzenediol were 2.1×10 cm^2/s and 2.7×10^6 cm^2/s, respectively. The electrocatalysis mechanism has been studied. ATR-FTIR was used for the characterization of the ME/Au SAMs. The oxidation currents were linear in the range of 1.0×10^(-7)~1.0×10^(-4)mol/L for metol and 6.0×10^(-6)~6.0×10^(-4)mol/L for p-benzenediol, with the correlation coefficients of 0. 9992 and 0.9996 by differential pulse voltammetry, and detection limit 2.0×10^(-8)mol/L and 1.2×10^(-6) mol/L for metol and p-benzenediol, respectively.

采用水平衰减全反射－傅立叶变换红外光谱技术对ME/Au SAMs进行了表征，示差脉冲伏安法同时测定米吐尔和对苯二酚，不产生干扰，其氧化峰电流与相应物质的浓度分别在1.0×10^(-7)~1.0×10^(-4)mol/L和6.0×10^(-6)~6.0×10^(-4)mol/L范围内呈良好的线性关系，相关系数分别为0.9992和0.9996，检测限分别为2.0×10^(-8)和1.2×10^(-6)mol/L。

She gently rebuff ed him, but agreed that they could be friends

她婉言拒绝了，但同意作为朋友相处。

If in the penal farm, you were sure to be criticized.

要是在劳改农场，你等着挨绳子吧！