铟-二甲酚橙络合吸附波的研究

铟(Ⅲ)在0.03mol/l邻苯二甲酸氢钾(KHP)、5×10~(-6)mol/l二甲酚橙(XO)溶液(pH3.9)中,出现一良好的示波极谱图,峰电位E_p=-0.68V(vs.SCE),其峰电流与铟的浓度在1.0×10~(-7)～3.0×10~(-6)mol/l范围内成线性关系,检测下限为5.0×10~(-8)mol/l。用等摩尔连续变化法确定络合物的络合比为In(Ⅲ):XO=1:1。用循环伏安法等电化学手段研究极谱波的性质及其反应机理。并测定了不同铟浓度时体系的吸附量。体系的吸附符合Frumkin吸附等温式,吸附系数β=4.3×10~5,吸引因数α=-1.75。实验表明,该波属于络合吸附波。     

Trace Determination of Zirconium（Ⅳ） by Anodic Adsorptive Voltammetry at a Carbon Paste Electrode

A new sensitive adsorptive voltammetric method was described for the determination ofzirconium at a carbon paste electrode (CPE) in the presence of alizarin complexone (ALC).Optimal analytical conditions are: 1.0~ l0“6 or 5.0x l0“7 mol/L ALC, 0.20 mol/L HAC-NaAc (pH4.3), accumulation for 60 s at 0 V (vs. SCE), and linear scanning from 0 V to 1.0 V at 250 mV/s.The peak potential of the complex is at 0.81 V. By using a model JP-303 polarographic analyzer,2.0~ l0l~ mol/L (S/N=3) zirconium can be detected with a 90 s accumulation, when the 2nd-orderderivative linear sweep technique is used, and the linear range is 6.0~ 10l~-2.0~ l0s mol/L (5.0~ l07mol/L ALC) and 2.0~108-2.0~ l07 mol/L (1.0~ 10.6 mol/L ALC), respectively. The developedmethod was applied to the determination of trace zirconium in the ore samples with satisfactoryresults.     

DH-2树脂对镝的吸附及机理

研究了镝离子在HD-2树脂上的吸附行为。在HAc-NaAc体系pH=6.20时吸附最佳,测得静态饱和吸附容量为356mg/g(树脂),用0.1~2.0 mol/L HC l可定量洗脱,表观速率常数k198=1.16×105s-1,表观活化能Ea=16.1kJ/mol。等温吸附服从Freun ilich经验式,吸附热力学参数△H=16.5kJ/mol,△S=58.2 J/(mol.K),△G298=-0.859kJ/mol。用化学和红外光谱等方法讨论了吸附机理。     

如何制备金属钾

工业上约于850℃时用钠还原熔融态氯化钾的方法制备金属钾,Na(l) KCl(l)K(g) NaCl(l)。从金属活泼性看,钠略弱于钾,ΔfH m[NaCl(s)]=-411kJ/mol,ΔfH m[KCl(s)]=-435 kJ/mol,就是说上述正向是吸能即ΔrH m为正值的反应。因钾比钠容易挥发,沸点分别为756·5℃、881℃,在该温度下     

负载二氧化锰球形吸附剂的制备及锂吸附性质的研究

将粉末状无机吸附剂MnO_2分散负载于交联聚丙烯酰胺,制成了球形吸附剂。以静态法和柱式法用LiOH(0.1mol/L),LiCl(0.1mol/L)混合溶液和实际盐湖卤水研究了吸附剂对Li~+的吸附性。对LiOH、LiCl等摩尔混合溶液和大柴旦湖水,锂吸附容量分别为5.90和3.40mmol/gMnO_2·HCl溶液(0.25mol/l)可将被吸附的锂近于完全洗脱,同时将吸附剂再生以重新使用。     

氩气中一氧化碳、二氧化碳、甲烷、乙烷混合气体标准样品的研制

介绍气体报警仪标定和检测使用的氩气中一氧化碳、二氧化碳、甲烷、乙烷气体标准样品的制备,以气相色谱法对其均匀性和稳定性进行考核,对定值结果的不确定度进行了评定。标准气体定值范围:一氧化碳为500～1000μmol/mol,不确定度2%;二氧化碳为1000～5000μmol/mol,不确定度2%;甲烷为300～500μmol/mol,不确定度3%;乙烷为300～500μmol/mol,不确定度3%。     

含氮芥基查尔酮类衍生物的合成、晶体结构及抗肿瘤活性

根据拼药原理,将氮芥类抗肿瘤药物的药效基团N,N-二(2-氯乙基)氨基拼接到查尔酮结构中,合成出了一系列新型含氮芥基的查尔酮衍生物3a～3r,并用1H NMR,IR,HRMS-ESI及X射线对其结构进行了确证.采用MTT法对所合成的化合物进行了体外抗肿瘤活性测试,结果表明部分化合物对所选肿瘤细胞的增殖有较强的抑制作用,其中,化合物3j和3l对K562的IC50值分别为20.01和18.6μmol/L;对HepG2的IC50值分别为43.46和21.39μmol/L.实验培养并得到了目标产物3e和3l的晶体结构,X射线分析表明化合物3e和3l都属三斜晶系,P-1空间群.     

碱性全固态纳米晶nio电容器的电化学电容特性

纳米晶nio;pva-koh(5 mol/l)-h2o;全固态电化学电容器     

离子色谱法测定氰化浸出液中金、银、铜、铁、钴、镍和锌的含量

氰化浸出液样品用0.45μm针头过滤器过滤,用离子色谱法测定氰化浸出液中金、银、铜、铁、钴、镍和锌等7种元素的含量。以IonPae AS11阴离子交换柱（2.0 mm×250 mm）为固定相,含0.02 mol·L^-1氢氧化钠和0.01 mol·L^-1氰化钠溶液作为流动相,于波长210 nm处进行紫外检测。7种金属的氰化物络阴离子在30 min内可完全分离。各元素的检出限（3S/N）在0.01～0.08 mg·L^-1之间。方法的加标回收率为94.0%～104%,测定值的相对标准偏差（n=7）均小于2.5%。     

单扫描极谱法测定土壤、蔬菜、水样中痕量氟

本文采用三电极系统,在0.08mol/L盐酸条件下,利用氟对锆(-水杨基荧光酮(SAF)-十六烷基三甲基溴化铵(CTMAB)三元络合体系的竞争抑制,用单扫描极谱法测定多样品中的痕量氟。最佳底液条件是:0.8mg/LZr(-1.4×10-4mol/L(SAF)-8.0×10-6mol/L(CTMAB)。其起始电位为-0.25V,峰电位在-0.65V(vs.SCE)左右,测氟的线性范围为40～640μg/L。检出限为2.0μg/L。本方法具有反应快、重现性好、检测灵敏、选择性好、操作方便的特点。本法适用于土壤,水样及蔬菜中微量氟的测定。用单扫描极谱法研究了氟的极谱行为,证明了该波为不可逆还原吸附波,讨论了电极反应机理。     

高效液相色谱法测定吡啶、2-氨基吡啶、2-甲基吡啶和2-吡啶甲酸

建立了以磷酸氢二钾-磷酸盐缓冲溶液中添加甲醇为流动相，以反相高效液相色谱同时测定吡啶、2-氨基吡啶、2-甲基吡啶和2-吡啶甲酸的新方法。在流动相为甲醇-0．1mol／L磷酸氢二钾和磷酸缓冲溶液、pH为6．0的最佳条件下，吡啶、2-氨基吡啶、2-甲基吡啶和2-吡啶甲酸的加标回收率分别为98．2％～102．1％、99．1％～101．3％、97．8％～100．7％和99．1％～102．4％；线性范围分别为20～980、18～913、19～943和18～902mg／L；检出限分别为2．0、1．8、1．9和1．8mg／L。本法可同时测定电氧化2一甲基吡啶过程中电解液。     

Verification of a method for microcoulometric determination of adsorbable organic halide pollutants in natural, drinking, waste, and treated waters

A microcoulometric method is described for the determination of organic-halide pollutants at 2-2000 microg/L in natural, drinking, waste, and treated waters. The conditions for the adsorption of organic halides, using a microcolumn with activated charcoal-and for the desorption of inorganic halides-as well as for the pyrolysis process, were optimized for the successful determination of priority organic halide pollutants. An appropriate criterion was proposed to stop the desorption step. The mean recovery was 100.3%, and the mean relative standard deviation was 9.9%. The detection limit based on 3 times the standard deviation of the blank sample was 2 microg/L.     

电感耦合等离子体光谱法(ICP-AES)测定银精矿中铜、铅、锌、砷、镉、钙、镁、锰含量

针对银精矿样品复杂,难消解的特点,研究了不同酸溶法和碱熔法对样品的消解情况,建立了硝酸,盐酸,氢氟酸,高氯酸消解银精矿的方法。根据元素灵敏度和抗干扰性,选定各元素的测定波长。通过酸溶样和碱熔样测定结果比对,验证了方法准确性。建立了四酸消解-电感耦合等离子体光谱法测定银精矿中铜、铅、锌、砷、镉、钙、镁、锰含量的方法,元素的线性相关系数均在0.9999以上。通过共存元素干扰实验,确定了银精矿中高含量元素(铜、铅、锌、铁、锑、铋等)对测定元素结果没有影响。方法检出限：Cu 0.0063 mg/L, Pb 0.0159 mg/L ,Zn 0.0090 mg/L,As 0.0192 mg/L, Cd 0.0093 mg/L ,Ca 0.0084 mg/L, Mg 0.0075 mg/L, Mn 0.0081 mg/L。测定下限：Cu 0.0105mg/L,Pb 0.0265 mg/L, Zn 0.0150 mg/L, As 0.0320 mg/L, Cd 0.0155 mg/L, Ca 0.0140 mg/L, Mg 0.0125 mg/L,Mn 0.0135 mg/L。3个样品的相对标准偏差在0.87%~3.56%之间,加标回收率在95.00%~103.56%之间。方法流程短,操作简单,快速,灵敏度和再现性高,结果准确可靠,可以满足银精矿中铜、铅、锌、砷、镉、钙、镁、锰含量的测定。     

毛细管电泳-质谱联用法测定清肺抑火片中的四种有效成分

建立了毛细管电泳-电喷雾电离质谱联用法同时测定清肺抑火片中苦参碱、药根碱、氧化苦参碱、栀子苷4种药效成分含量的分析方法.采用未涂层石英毛细管,以35 mmol/L乙酸铵(含20％乙腈,pH=6.5)为缓冲溶液、60％异丙醇(含3.3 mmol/L乙酸)为鞘液,分离电压为28 kV时,各组分在11 min内达到基线分离.苦参碱、药根碱、氧化苦参碱、栀子苷的线性范围分别为0.030～150 mg/L、0.060～20 mg/L、0.060～80 mg/L、0.60～300mg/L,检出限分别为0.010、0.020、0.020、0.20mg/L.样品的加标回收率在91.0％～107％之间,相对标准偏差均小于4.9％.方法简便、快速、灵敏度高,已成功用于清肺抑火片中的苦参碱、药根碱、氧化苦参碱、栀子苷含量的同时测定.     

Electrocatalytic Oxidation and Ion Chromatography Detection of S2O32-, SO32-, I- and SCN- at Glassy Carbon Electrode with Functionalized Multi-Wall Carbon Nanotubes Film

In this research, a glassy carbon electrode modified with the functionalized multi-wall carbon nanotubes (MWNT-COOHs) film was used as an amperometric sensor for the determination of S2O32-, SO23-, I- and SCN-. The electrochemical behavior of those oxidizable inorganic anions at this modified electrode was studied by means of cyclic voltammetry(CV). The experimental results indicate that the modified electrode exhibits a high electrocatalytic activity towards the oxidation of those anions with a relatively high sensitivity, a good stability and a long-life. Separated by ion chromatography(IC) with 1.25 mmol/L H2SO4 as an eluent,those oxidizable anions can be determined by the MWNT-COOHs modified electrode successfully. Under the optimal chromatographic conditions, the detection limits are 1.5 × 10-7 mol/L for S2O23-, 2. 5 × 10-7 mol/L for SO32-, 1.2 × 10-7 mol/L for I- and 2. 0 × 10-7 mol/L for SCN-, respectively. The method was applied successfully to the determination of those anions in environmental water.     

Determination of benzoate,sorbate, citrate and orthophosphate ions in beverage samples using two-dimensional isotachophoretic method

A two-dimensional capillary isotachophoretic method (cITP-cITP) using electrolyte system consisting of leading electrolytes (LE1): [10 mM HCl + β-alanine (pH 3.9) + 0.1% hydroxyethylcellulose (HEC)] and (LE2): [10 mM HCl + aminocaproic acid (pH 5.00) + 0.1% HEC], and 5 mM caproic acid as terminating electrolyte (TE) was studied. Two methods of detection, conductometric and UV-Vis, were applied to the determination of selected food preservatives and additives. Practical applicability was demonstrated by simultaneous determination of benzoates, sorbates, citrates and orthophosphates in 12 samples of beverages. The proposed method revealed linearity with R ² between 0.9992 and 0.9999 for the concentration ranges: 10–100 mg/L (orthophosphate and citrate ions), 20–100 mg/L (sorbates) and 40–120 mg/L for benzoates. The detection limits for all studied ions were from 0.85 to 3.1 mg/L whereas the quantification ones were from 2.8 to 10 mg/L. The variation coefficients for five-fold analysis of all ions ranged between 0.4 and 9.1%. Obtained recoveries (from 97 to 104%) confirmed satisfactory accuracy of the proposed cITP-cITP method for the determination of tested food additives.     

碱化底液消除水负峰离子色谱法测定水中F~–,Cl~–等7种阴离子

在研究消除水负峰的基础上,建立离子色谱法测定水中F–,Cl–,NO2–,H2PO4–,Br–,NO3–,SO42–7种阴离子的方法。经实验确定淋洗液为4.5 mmol/L NaHCO3–4.0 mmol/L Na2CO3,淋洗液流量为1.0 mL/min,柱箱温度为35℃。在底液中加入与淋洗液同浓度的Na2CO3–NaHCO3可有效消除水负峰。该方法对7种阴离子的检出限为0.004~0.034 mg/L,测定结果的相对标准偏差为0.69%~3.57%(n=6),加标回收率为95%~105%。该法能有效消除水负峰及其对F–测定的影响,操作简便、测定结果准确可靠,适用于水中F–、Cl–等7种阴离子的测定。     

溶剂萃取-电感耦合等离子体原子发射光谱法同时测定钢铁中铅、砷、锑、铋、锡

本文拟定了在4.05mol/L硫酸介质中,0.5mol/L碘化铵存在下,以甲基异丁基酮(MIBK)萃取钢铁中铅、砷、锑、铋、锡。然后以4mol/L硝酸反萃取,水相经浓缩定容后以电感耦合等离子体直读光谱仪进行同时测定的新方法。铜同时被萃取,对铋的测定产生光谱干扰,输入干扰系数加以修正。该方法已应用于我厂日常生产的各类合金钢及高温合金中。站果令人满意。     

非抑制型离子色谱法测定碱金属、铵离子和烷基胺

 采用非抑制型离子色谱法、以氨磺酸作流动相分离测定了Li+ 、Na+ 、NH+ 4、K+ 、甲胺、乙胺和正丙胺等 7种物质 ,研究了氨磺酸流动相浓度对溶质保留值的影响。结果发现 ,随着流动相浓度的增大 ,溶质保留值减小 ;适宜的流动相浓度为 4 0mmol/L。以 4 0mmol/L氨磺酸为流动相测得上述 7种物质的检出限及工作曲线的线性回归方程。方法应用于自来水试样的分析 ,结果良好。     

Determination of benzylpenicillin, oxacillin, cloxacillin, and dicloxacillin in cows' milk by ion-pair high-performance liquid chromatography after precolumn derivatization

A high-performance liquid-chromatographic method has been developed for the determination of five penicillin compounds (benzylpenicillin, phenoxymethylpenicillin, oxacillin, cloxacillin, and dicloxacillin) at trace levels in commercially available milk samples. This method comprises extraction of the lipids with ethyl acetate, clean-up and concentration on a C-18 solid-phase extraction column, and derivatization with 1,2,4-triazole and mercury(II) chloride solution, pH 8, at 65 degrees C for 10 min. The derivatized compounds are eluted from a C-2 column with a mobile phase containing acetonitrile and phosphate buffer loaded with sodium thiosulfate and tetrabutylammonium hydrogen sulfate as ion-pairing reagent. The limit of determination was found to be 4 microg L(-1) milk for benzylpenicillin and 10 microg L(-1) for the others. This meets EU criteria according to decision No. 93/256/EEC.