新烟碱类杀虫剂检验方法研究进展

新烟碱类杀虫剂因其广谱杀虫毒性、对哺乳动物的低毒性和施用灵活性等优点，已成为全球应用最广泛的杀虫剂。然而，其大量使用已导致昆虫、鸟类等生物数量的减少，在环境、食品中的残留也给人类健康造成威胁，因此开发有效的检验方法至关重要。本综述概述了新烟碱类杀虫剂的样品前处理和检测方法，前处理方法包括分散液液微萃取法、传统固相萃取法、磁性固相萃取法、分散固相萃取法、QuEChERS法等，检测方法包括高效液相色谱法、液相色谱-质谱联用法、免疫分析法、传感器法等。此外，简要概述了新烟碱类杀虫剂在生态环境、食品安全、人类健康方面的残留风险，并对新烟碱类杀虫剂检验的未来发展方向进行展望，以期为法庭科学领域开展相关检验研究提供参考。     

生物样品中镇静类药物检测的研究进展

综述了近10年来生物样品中镇静类药物的检测方法(包括高效液相色谱法、气相色谱-质谱法、液相色谱-串联质谱法和液相色谱-高分辨质谱法等)和样品预处理方法(包括液液萃取法、固相萃取法、分散固相萃取法和柱切换法等)的研究进展,并对其前景作了简要展望(引用文献45篇)。     

食品中甲霜灵残留的样品前处理技术及检测方法研究进展

甲霜灵作为一种农田中常用的杀菌剂,主要用于防治豌豆、马铃薯、水稻等农作物的霜霉病、黑胚病、薯晚疫病等。不规范使用甲霜灵会造成农药残留,残留的甲霜灵通过食物链富集效应导致食品安全问题。目前,对于甲霜灵检测的样品前处理技术包括QuEChERS法、分散液-液微萃取法、温度控制分散液-液微萃取法、基质固相分散萃取法、磁固相萃取法等。检测方法包括色谱法、色谱-质谱法、基质辅助激光解吸电离-成像质谱法、胶体金免疫层析法以及酶联免疫吸附法。本文综述了近年来食品中甲霜灵残留的样品前处理技术及检测方法,并对其发展方向进行了展望,旨在为食品中甲霜灵残留的检测和监控提供参考。     

土壤和沉积物中多环芳烃分析技术研究进展

综述了近年来土壤和沉积物中多环芳烃分析技术的研究进展。重点阐述了索氏提取、超声波提取法、加速溶剂萃取法、微波辅助萃取法、超临界流体萃取法、固相微萃取法、柱层析法、固相萃取法、凝胶渗透色谱法等前处理技术和气相色谱-质谱法、高效液相色谱法和超高效液相色谱法等分析方法,并展望了未来发展的趋势(引用文献71篇)。     

水体中合成麝香检测方法的研究进展

合成麝香被广泛应用于个人护理产品和生活用品中,在环境中的污染程度呈逐年上升的趋势,准确测定环境中合成麝香的含量具有重要意义。综述了水体中合成麝香的前处理方法(包括固相萃取法、固相微萃取法、液液萃取法、液液微萃取法、索氏提取法、超声辅助提取法、加速溶剂萃取法和QuEChERS等)和仪器分析方法(包括气相色谱-质谱法、气相色谱-串联质谱法、高效液相色谱法、液相色谱-串联质谱法和新型荧光光谱法等),并对相关研究领域的发展趋势进行了展望(引用文献52篇)。     

复杂基体中痕量多环芳烃分析测定方法的研究进展

介绍了环境样品（水和土壤）以及植物油中痕量多环芳烃的分析检测方法。对样品的预处理过程和分析方法做了评价。采用一些新的预处理方法（包括液相色谱法、固相萃取法、超临界二氧化碳萃取法）,并结合色谱-质谱在线联用分析检测方法能够获得比较理想的分析结果。引用文献52篇。     

食品及食品包装材料中光引发剂分析方法的研究进展

综述了食品及食品包装材料中光引发剂分析方法的研究进展,包括样品的前处理方法(如固相萃取、固相微萃取、基质分散固相萃取、加速溶剂萃取、分散液液微萃取、凝胶渗透色谱)和分析方法(如气相色谱-质谱法、气相色谱-串联质谱法、液相色谱法、液相色谱-串联质谱法、超高效合相色谱法),并对其发展趋势作了展望。     

分散固相萃取-气相色谱-质谱法分析蕨菜、黑米中53种农药残留量

采用分散固相萃取(Dispersive solid-phase extraction)样品前处理方法,建立了蕨菜、黑米等生态农产品中53种农药残留的气相色谱一质谱(GC-EI/MS)的分析方法.样品由含0.1%冰醋酸的乙腈提取,以环氧七氯为内标,经分散固相萃取法净化.每种农药选择了合适的离子及其驻留时间,采用气相色谱-...     

四极杆/静电场轨道阱高分辨质谱在青椒中农药多残留快速筛查的应用

建立了分散固相萃取法(d-SPE)萃取,高效液相色谱-四极杆/静电场轨道阱高分辨质谱快速筛查青椒中农药多残留的分析方法。样品采用乙腈提取,经N-丙基乙二胺(PSA)和C18分散固相萃取净化,以BEH C18色谱柱为分析柱,0.1%甲酸乙腈及含0.1%甲酸和4 mmol/L甲酸铵水溶液作为流动相进行梯度洗脱分离。采用正、负离子切换,同时对欧盟青椒定性和定量考核样品进行快速筛查,并对定量考核样品筛查到的16种农药进行定量测定。16种农药在一定浓度范围内呈良好的线性关系,相关系数(r2)大于0.995,该方法的定量下限为0.4~2.0μg/kg。在不同加标水平下的平均回收率为81.6%~116.5%,相对标准偏差为0.4%~7.5%。以欧盟青椒定量考核样品为研究对象,对其分别进行四极杆/静电场轨道阱高分辨质谱和三重四极杆质谱测定,结果表明,四极杆/静电场轨道阱高分辨质谱定量结果可与三重四极杆质谱结果相媲美。本方法简单、灵敏、准确,适用于农产品中农药多残留的快速筛查和分析测定,具有很好的实际应用价值。     

分散固相萃取-分散液液微萃取/高效液相色谱法测定西瓜中氟唑菌酰羟胺残留

采用分散固相萃取和分散液液微萃取联用的方法,建立了高效液相色谱快速检测西瓜中氟唑菌酰羟胺残留的分析方法。使用乙腈和水混合溶液作为萃取溶剂,经N-丙基-乙二胺硅烷(PSA)固相萃取吸附剂净化提取液,分散液液微萃取将目标物富集到1,1,2,2-四氯乙烷溶剂中,采用高效液相色谱进行分析。考察了萃取溶剂的种类与体积、分散剂体积及盐浓度等因素对分散液液微萃取萃取效率的影响。结果表明:分析物的质量浓度在0.01~5 mg/L范围内与峰面积的线性关系良好,相关系数(r)为0.999 9,定量下限(S/N=10)为0.01 mg/kg。加标水平为0.01、0.1、1 mg/kg时,平均回收率为89.2%~94.5%,相对标准偏差(n=5)为3.0%~8.7%。该方法简单、高效、灵敏度高,适用于西瓜中氟唑菌酰羟胺的残留检测。     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

Acid hydrolysis of carboxymethylcellulose of low degree of substitution

Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

Estimation of Kinetic Parameters of Thermal Oxidation of Ilmenite

The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe₂O₃. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.     

Mechanism of action of base-catalyzed oxygenation of phenol derivatives

Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。     

化学计量中不确定度评定研究进展

测量不确定度是表征合理地赋予被测量之值的分散性的参数。本文针对化学计量不确定度评定基础模型仅适用于线性模型、概率分布为正态分布或缩放位移t分布等局限,介绍了近年来不确定度评定的研究热点:蒙特卡罗方法(Monte Carlo Method,MCM),不确定度评定的来源、评定概念、评估方法及其发展过程,扩大了测量不确定度评定与表示的适用范围。