不分流/分流进样毛细管气相色谱法测定酱油中的山梨酸和苯甲酸

采用不分流／分流进样模式,以FFAP毛细管作色谱分离柱、丙酮作溶解样品提取物的溶剂,用气相色谱法测定酱油中的山梨酸和苯甲酸。线性范围均为25～300μg/mL,相关系数都大于0．9990,山梨酸和苯甲酸的检出限分别为0、813、0．606μg/mL,测定结果的相对标准偏差(n=3)分别为1．43％～3．77％、2．11％～4．62％,回收率分别为84．4％～96．2％、86．2％～92．5％。     

氢化物-原子荧光光谱法连续测定锌精矿中砷、锑、铋、锡

用氢化物-原子荧光光谱法,一次性分解样品,在L-半胱氨酸存在下,实现了锌精矿中As、Sb、Bi、Sn的连续测定。其回收率分别为92．8％～105．0％、96．0％～109．3％、96．0％～111．6％和96．7％～103．7％;检出限分别为0．35、0．31、0．19和0．35μg／L。用该方法分析锌精矿样品,结果满意。     

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。     

流动注射在线预富集-高效液相色谱法测定四种硝基类化合物

建立了以香烟过滤嘴纤维作吸附剂,在线固相萃取-高效液相色谱（SPE—HPLC）测定水中邻硝基苯甲酸、对硝基苯胺、邻硝基苯酚、3-氯硝基苯四种硝基类化合物的方法。邻硝基苯甲酸、对硝基苯胺、邻硝基苯酚、3-氯硝基苯分别在0．006～4．80、0．003～2．40、0．002～1．60、0．002～1．60mg／L范围内峰面积与浓度呈线性关系,相关系数分别为0．9994、0．9996、0．9997和0．9996;检出限（S／N=3）分别为1．0、0．8、0．6,0．6μg／L;富集倍数分别为28．2、176．6、172．1、153．3。该法用于河水中四种硝基类化合物的测定,回收率为85．41％～116．44％,相对标准偏差在1．1％～5．4％范围内。     

阻抑速差催化光度法测定痕量色氨酸和酪氨酸

研究了色氨酸、酪氨酸在硫酸环境中抑制碘对亚砷酸与硫酸铈氧化还原反应的催化作用及动力学条件。在0．001mol／L Ce(SO4)2,0．00125mol／L As2O3,0．013mg／L KI,0．025g／L和0．25g／L NaCl溶液中测定色氨酸和酪氨酸,其线性范围分别为0．0～0．65mg／L,0．0～4．0mg／L和0．0～1．3mg／L。0．10～4．0mg／L,用联立方程分别求出各自含量。用此法对醇溶蛋白质和混合氨基酸溶液中色氨酸和酪氨酸进行测定,混合氨基酸的色氨酸、酪氨酸测量值为0．8037g／L,3．591g/L;蛋白质的色氨酸、酪氨酸测量值为1．8g/kg、3．43g/kg;回收率在88％～109％;色氨酸和酪氨酸的RSD分别为4．8％和5．2％,结果满意。     

氢化物原子荧光光谱法测定虾中砷和汞

建立了氢化物原子荧光法同时测定虾中砷和汞的方法。研究了样品前处理及实验条件对测定砷、汞的原子荧光强度的影响，并探讨了共存离子对测定砷、汞的干扰和消除的方法。本方法具有操作简便、快速、灵敏度高等优点，砷和汞的检出限分别为0．026μg/L和0．020μg／L；相对标准偏差分别为1．7％～9．4％和1．2％～9．4％；回收率为98％～106％。     

小麦粉中过氧化苯甲酰与苯甲酸总量的毛细管气相色谱法测定

报道了测定小麦粉中作为增白剂的过氧化苯甲酰及残留苯甲酸总量的改进方法。小麦粉通过酸性乙醚．石油醚(60～90℃)萃取,其中过氧化苯甲酰同时被还原成苯甲酸,经石英毛细管气相色谱柱DB-WAX分离,氢火焰离子化检测器检测,以外标法定量。方法的相对标准偏差为4．8％～9．1％;线性范围为0．005～0．1g／L(r=0．996);检出限为2．0mg／L;回收率为90．0％～96．5％。将该法应用于小麦粉中过氧化苯甲酰及残留苯甲酸总量的分析,结果令人满意。     

高效毛细管电泳电导法快速检测复方维生素B片中的VBl、VBl2、VB6和VC

采用高效毛细管电泳电导法同时分离、测定了复方维生素B片中的主要成分VB1，VB12，VB6和VC的含量。研究了运行缓冲溶液的酸度和浓度、电泳电压、进样时间等因素对电泳的影响。在优化的实验条件下：40mmol/L Tris-4mmol/L H3BO3(pH8．0)的缓冲溶液中加入0．30mmol/L CTAB(溴化十六烷基三甲基铵)，分离电压为15kV，上述4组分在5min内得到良好的分离。维生素B1，B12，B6和VC的线性范围分别为5．5～1．0mg/mL；15～1．5mg／mL;1．0～0．40mg／mL和6．6～0．80mg／mL；检测限分别为0．80μg/mL，4．0μg/mL，0．50μg/mL，2．9μg/mL；5次测定峰高的相对标准偏差分别为2．2％，1．6％，3．9％，2．8％。5次测定的平均回收率分别为99％，94％，l00％，97％。     

固体吸附-毛细管气相色谱法测定环境空气中的偏二甲肼

采用固体吸附-毛细管气相色谱法测定环境空气中偏二甲肼的含量,色谱峰高与偏二甲肼浓度在0～13．8mg／L范围内线性关系良好,当采样体积为60L时,检出限和测定下限分别为0．37μg／m^3和1．2μg／m^3。低、中、高3种浓度的偏二甲肼标准溶液测定结果（n=6）的相对标准偏差分别为3．5％,2．6％,1．9％,样品加标回收率为84．5％～101．0％。     

ASE-HPLC检测某型号球形发射药中的叠氮硝胺、硝化甘油、Ⅱ号中定剂含量的研究

采用快速溶剂萃取（ASE）技术和高效液相色谱法测定某球形药中叠氮硝胺（DIANP）、硝化甘油（NG）和Ⅱ号中定剂（C2）的含量．ASE提取条件：二氯甲烷做萃取溶剂,萃取温度100℃,静态萃取10min,萃取2次．HPLC测定条件：YWGC18柱（150×4．6mm,10μm）,以甲醇和水作为流动相,梯度洗脱,流速1 mL／min,检测波长210nm．测定结果表明DIANP、NG、C2平均回收率分别为99．6％、100．3％、99．4％,RSD分别为0．7％、0．8％、0．9％（n=5）,检出限分别为2.1、1.5和0．2mg／L,线性范围分别为0．02～0．98g／L,0．03～1．38g／L,0．002～0．124g／L．用此方法共检测某批球形发射药样品5份,检测结果与滴析-HPLC法检测结果相当．     

电堆集富集非水毛细管电泳同时测定水杨酸、肉桂酸、阿魏酸和香草酸

建立了同时分离测定水杨酸、肉桂酸、阿魏酸和香草酸的电堆集富集-非水毛细管电泳(NACE)的新方法。运行缓冲溶液为40mmol/L乙酸钠-2.5mmol/L氢氧化钠甲醇溶液,电压-25kV,在225nm波长下紫外检测。对电压、乙酸钠浓度、氢氧化钠浓度、进样时间、样品溶液等因素对电堆集及分离的影响做了系统的研究。水杨酸、肉桂酸、阿魏酸和香草酸分别在1.4~28mg/L、0.40~8.0mg/L、0.7~18mg/L和0.7~30mg/L范围内线性关系良好(r=0.9999、r=0.9997、r=0.9994、r=0.9997);回收率分别为95.8~99.6%、96.2~98·2%、95.7~105%和98.9~103%,基于3倍信噪比(S/N=3),4种有机酸的检出限分别为0.069、0.051、0.107和0.089mg/L。     

离子色谱法测定乙醛酸中的顺丁烯二酸和乙二酸

采用抑制电导离子色谱法测定高浓度乙醛酸基体中痕量的顺丁烯二酸和乙二酸。将乙醛酸样品稀释至1 000倍体积后,采用高浓度的淋洗液,以高容量色谱柱对样品进行分析。实验结果表明,顺丁烯二酸和乙二酸最低检出限分别为12.7,19.6μg/L,重现性(n=5)分别为1.13%,1.11%,回收率分别为97.9%,94.7%。该方法具有较高的灵敏度,适用于乙醛酸的例行检测。     

Determination of Cyanuric Acid or Trichloroisocyanuric Acid in Air

Abstract

An analytical procedure for measurement of cyanuric acid or trichlor oisocyanuric acid in air has been developed. The procedure involves air sampling with a 37-mm PVC membrane filter, recovery with a phosphate buffer, and analysis by high performance liquid chromatography with a UV detector at 225 nm. The interior surface of the front piece of the cassette filter holder also is analyzed. Average recoveries were 0.98 to 1.00 after fortification of PVC filters with 12- to 412-μg quantities of cyanuric acid. Average recoveries of trichloroisocyanuric acid were 0.83 to 0.98 after fortification of glass surfaces with 12- to 424-μg quantities (these are reasonable approximations for recoveries of trichloroisocyanuric acid from PVC filters). The analyst should ascertain which analyte is present at the sampling site because trichloroisocyanuric acid reacts with water in the phosphate buffer to form cyanuric acid in high yield.     

对氨基苯甲酸的合成研究进展

综述了以对硝基苯甲酸为原料合成对氨基苯甲酸的近期研究进展。并从技术和经济角度讨论了各种合成方法的优点与不足。     

Surface Functionalization of Magnetite Nanoparticles with Sulfonic Acid and Heteropoly Acid: Efficient Magnetically Recoverable Solid Acid Catalysts

New magnetically recoverable solid acid catalysts for acid‐catalyzed reactions were designed via the surface chemical functionalization of silica‐coated magnetite nanoparticles (SCMNPs) with sulfonic acid groups. First, the SCMNPs were covalently functionalized with 3‐aminopropyl groups to achieve Amp‐SCMNPs. Then, reaction of the Amp‐SCMNPs with 1,4‐butane sultone followed by acidification with phosphotungstic acid (HPW) or diluted sulfuric acid produced magnetically recoverable solid acid catalysts, HPW‐ampsul‐SCMNPs and H‐ampsul‐SCMNPs, respectively. Both catalysts were characterized by various physicochemical analyses such as Fourier transform infrared (FT‐IR) and inductively coupled plasma‐optical emission (ICP‐OES) spectroscopies, vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray diffraction (XRD), and energy‐dispersive X‐ray (EDX) analyses. Finally, the catalytic activities of the prepared catalysts were examined in the esterification of acetic acid with butanol and acetalization of benzaldehyde with ethylene glycol. Excellent catalytic efficiencies were obtained in both cases. The catalysts were consecutively recovered and reused five times without significant loss of their activities.     

以对甲基苯磺酸作为淋洗液用离子色谱法测定酸雨中的有机酸

本文研究了用对甲基苯磺酸作为淋洗液测定液相中HCOO~-和CH_3COO~-的离子色谱条件,该方法对HCOO~-和CH_3COO~-的最低检出限分别为48ppb和93ppb。该方法与用进口的辛磺酸作为淋洗液的方法进行了对比实验,并用于两广实际酸雨样品中甲酸和乙酸的测量。     

Mechanochemical Complexation between Deoxycholic Acid and Salicylic Acid

A complex between deoxycholic acid (DCA) and salicylic acid (SA) was prepared by grinding and coprecipitation methods. The resultant complex was characterized by means of powder X-ray diffractometry, IR spectroscopy and thermal analysis. The stoichiometry (DCA : SA 1 : 1) of the complex obtained by grinding was identical to that obtained by coprecipitation. The powder X-ray diffraction pattern of the DCA–SA complex differed from the typical pattern of DCA–guest complexes such as DCA–camphor and DCA–phenanthrene complexes. IR spectra suggested that a different kind of hydrogen bonding was formed in the crystal of the DCA–SA complex, compared with the other DCA–guest complexes. This was in good agreement with data from the crystal structure.     

硝酸氧解法提高泥炭中黄腐酸的产率

硝酸氧解法提高泥炭中黄腐酸的产率;腐植酸;硝酸氧化降解     

Determination of Monochloroacetic Acid and Dichloroacetic Acid for Quality Control of Acetic Acid Chlorination Industry by Ion Chromatography

An ion chromatographic method is described for the purpose of quality control in the process of monochloroacetic acid production. Using 2.5 mM NaOH–10% methanol as eluent, the simultaneous determination of acetic acid, monochloroacetic acid, dichloroacetic acid, and Cl⁻ was obtained in a single run. Monochloroacetic acid and dichloroacetic acid showed good linearity in the range 0.1–20 and 0.15–20 μg/ml and correlation coefficients were 0.9999 and 0.9998, respectively. The detection limits (signal-to-noise ratio 3:1) of monochloroacetic acid and dichloroacetic acid were 17 and 25 ng/ml. This simple, sensitive, and time-saving method can be applied for composition analysis in acetic acid chlorination production.