方波伏安法快速测定饲料中磷含量

运用方波伏安法快速测定溶液中过量的铅离子从而间接测定无机磷含量。在最佳试验测定条件下方波伏安峰高ip(μA)与磷的浓度(c)在0.2～20μg/mL内有良好的线性关系,回归方程为ip=54.82-2.39c,相关系数r=0.9876,检出限为0.085μg/mL,相对标准偏差(RSD)为2.44%,加标回收率为95%～99%。     

阴离子对加入到土壤中的铅吸附与提取的影响

The effect of accompanying anions on the adsorbability and extractability of Pb added in soils was studied by using bach equilibria and incubation-extraction mothods.Pb concentration ranged between 0.48-2.41 mM in the adsorption experiment,and Pb added to soil from 2.14 to 19.31mM Pb/kg with an incubation time of 2-16 weeks in the incubation-extraction test in which 1M NH4OAc(pH 7) was taken as an extraction agent,and the Pb compounds used are PbCl2,Pb(NO3)2 and Pb(OAc)2.The values of pH50 for Pb retention and the parameters,b and k values,of Langmuir equation were used to distinguish the difference of adsorbability and extractability of Pb affected by anions,respectively.Judging from the results of either pH50 value or b value,the influences of Cl^- and NO3^- on the adsorbability and extractability of Pb in soils were similar but quite different from those of OAc^-.The relative loading capacities of soils to Pb calculated according to the extraction rate showed that the values of Pb(OAc)2 were higher than those of PbCl2 and Pb(NO3)2.     

硝酸铅和金属铅作为对照品测定铅含量方法的探讨

探讨了硝酸铅和金属铅作为对照品测定铅含量的方法。结果表明,二者铅的测定值没有明显差异(P≥0.05),硝酸铅溶液比金属铅溶液相对稳定,因此,以硝酸铅代替金属铅作为对照品,操作简便、使用安全,具有较强的实际应用价值。     

硝酸铅对分葱根尖染色体的毒性效应

以分葱根尖为试验材料,研究了硝酸铅对分葱根尖的毒性效应.用不同浓度(0、0.1、1、10、50 mg/L)的硝酸铅水溶液对分葱根尖细胞染毒6、18、24h,观察分葱根尖细胞有丝分裂指数、微核率以及染色体畸变情况.结果表明:在试验剂量范围内,随着硝酸铅水溶液浓度的升高和染毒时间的增长,分葱根尖细胞的有丝分裂指数逐渐降低,染色体畸变率逐渐增大,微核率逐渐增大,并且均在硝酸铅水溶液浓度为50 mg/L、染毒时间为24h时达到最大值.     

微量穴醚(2.2.2)测定方法初探

用紫外分光光度法研究微量穴醚(2.2.2)的检测方法,并将该方法用于氟[18F]脱氧葡萄糖中微量穴醚(2.2.2)测定.将适量苯甲醛加入硝酸铅缓冲溶液中配制储备液,使溶液在250 nm检测波长处的吸收曲线为一平台,用储备液和微量穴醚(2.2.2)配制供试液,用紫外分光光度法检测.穴醚(2.2.2)的线性范围为1.0～10.0 μg/mL,相关系数0.999 5,平均回收率为100.5%(n=5),相对标准偏差为2.24%,方法检出限(3d)为0.15μg/mL.该方法用于氟[18F]脱氧葡萄糖中微量穴醚(2.2.2)测定,结果良好.该方法精密度高,准确性好,可用于微量穴醚(2.2.2)测定.

Abstract：

A method for the determination of trace cryptand 222 by ultraviolet spectrometry was researched. As benzaldehyde and complex of lead cryptand 222 possess the same ultralviolet absorbance peak and their maximum absorbance wavelength are both 250 nm, proper amount of benzaldehyde and lead nitrate was added to the citric acid buffer solution (pH=6.4) for preparing storage solution, and the ultralviolet absorbance curve of the storage solution was made a platform about 250 nm detection wavelength.Trace cryptand 222 was added to the storage solution, and trace complex of lead cryptand 222 was detected by ultraviolet spectrometry for quantitative determination of trace cryptand 222. This method kept in good linearity from 1.0 to 10.0 μg/mL of cryptand 222 concentration with a correlation coefficient of 0. 999 5, a recovery of 100.5% (n=5), a relative standard deviation of 2.24% and a limit of quantification of 0.15 μg/mL. This method has been successfully applied in determination of trace cryptand 222 of [18F]-fluorodeoxyglucose with satisfactory results. This method is simple, accurate and suitable for determination of trace cryptand 222.     

硝酸铅对大蒜根尖细胞有丝分裂的影响

采用不同浓度硝酸铅分别处理大蒜根尖,试验结果表明：随着硝酸铅质量浓度的增加(0．01,0．1,1,5,10,100μg/mL)和染毒时间(6,18,24h)的延长,细胞的增殖率下降,有丝分裂指数逐渐降低,由12．5％降至5．65％,而且在有丝分裂的细胞中还出现微核、滞后染色体、染色体桥等畸变现象。这说明铅对植物具有毒害作用。     

重金属检查法的介绍

重金属系指在实验条件下能与硫代乙酰胺或硫化钠作用显色的金属杂质。标准铅溶液的制备为称取硝酸铅160毫克，置1000毫升量瓶中，加硝酸5毫升与水50毫升溶解后，用水稀释至刻度，摇匀，作为贮备液。临用前，精密量取贮备液10毫升，置100毫升量瓶中，加水稀释至刻度，摇匀，即得（每1毫升相当于10微克的铅）。配制与贮存用的玻璃容器均不得含铅。     

不同浓度的硝酸铅对杂交水稻种子萌发及幼苗生长的影响

为了了解不同浓度的硝酸铅对杂交水稻种子萌发情况及幼苗生长情况中形态指标和生理生化指标的影响。实验材料选用的是田两优4号水稻品种来,对照组为清水,配制0.20g/L、0.40g/L、0.60g/L、0.80g/L、1.00g/L5个不同浓度梯度的硝酸铅。本实验为水稻种子在工业地区,尤其铅排放地区的水稻种子生长提供了一定的理论依据。     

硝酸铅对绿豆苗的毒性研究简

[目的]探讨硝酸铅对绿豆苗的毒性.[方法]以绿豆苗为试验材料,通过研究不同浓度（0、100、200、400、600 mg/L）的硝酸铅对绿豆苗生长发育及多酚氧化酶活性、过氧化氢酶活性、叶绿素含量的影响,初步探讨硝酸铅对绿豆苗的毒性作用.[结果]绿豆苗培养5d后,硝酸铅对绿豆苗叶和根的IC50分别为276.33、6.47 mg/L;随着硝酸铅浓度的升高,绿豆芽叶中PPO活性表现为抑制-诱导效应,绿豆芽根中PPO活性表现为诱导-抑制效应;绿豆芽叶和根中CAT活性表现为诱导-抑制效应;绿豆芽叶中的叶绿素含量表现为抑制效应.[结论]该研究为及时发现并排除重金属铅污染提供了理论和直观依据.     

硝酸铅对小麦根尖细胞遗传毒性效应

用不同离子浓度的硝酸铅(0.01,0.10,1.00,5.00,10.00,100.00 mg/L)对小麦根尖进行染毒处理6 h和12 h,观察小麦根尖细胞的微核率、有丝分裂指数和染色体畸变情况.结果表明:在相同Pb2+浓度下,随染毒时间的延长,细胞微核率增加.有丝分裂指数逐渐降低;在相同染毒时间下,随着Pb<2+浓度的增加,细胞的微核率逐渐增加,有丝分裂指数逐渐降低.在一些有丝分裂的细胞中,出现滞后染色体、染色体桥和断片等,说明硝酸铅对小麦具有遗传毒害作用.