QuEChERS/液相色谱－串联质谱测定猪肉中赛拉嗪及其代谢产物2，6-二甲基苯胺

建立了QuEChERS/液相色谱－串联质谱测定猪肉样品中赛拉嗪及其代谢产物2,6-二甲基苯胺（DMA）的新方法。样品匀浆后经乙腈－2%乙酸提取、C18吸附剂/N-丙基乙二胺（PSA）净化处理,提取液经氮吹、定容后,以0.1%甲酸－水溶液和0.1%甲酸－乙腈溶液为流动相,采用Waters C18色谱柱（100 mm × 2.1 mm,3.5 μm）进行分离,正离子模式下多反应监测模式检测,基质匹配外标校准曲线定量。赛拉嗪和DMA的线性范围均为0.2～500 μg/L,检出限分别为0.10、0.30 μg/kg,定量下限分别为0.32、1.00 μg/kg,加标回收率分别为95.6%～108%和70.3%～79.5%,相对标准偏差（RSD）分别为2.6%～2.8%和3.1%～5.0%。该方法成功应用于市售猪肉中赛拉嗪和DMA的检测,为肉制品中赛拉嗪和DMA的检测提供了一种简单、快速、灵敏的新方法。     

快速溶剂萃取-离子色谱-质谱法测定人体血液、尿液中的氟乙酸

建立了快速溶剂萃取-离子色谱-质谱法测定人体血液、尿液中氟乙酸的方法。以去离子水为萃取溶剂，使用快速溶剂萃取仪处理血液和尿液样品，取上清液依次经超滤管和0.22μm水相针式滤膜净化，稀释50倍后进样检测。采用Ion Pac AS20离子色谱柱以15.0 mmol/L的KOH溶液为淋洗液进行等度淋洗，流出液通过抑制器后进入三重四极杆质谱，在负离子、多反应监测模式下检测，外标法定量。结果表明，氟乙酸在0.5～500.0μg/L范围内线性关系良好(r>0.999),检出限和定量限分别为0.14、0.47μg/L。氟乙酸在血液和尿液中的回收率分别为93.4%～95.8%、96.2%～98.4%,日内精密度分别为0.8%～1.6%、0.2%～1.0%,日间精密度分别为2.3%～3.8%、3.9%～6.9%。进一步考察发现该方法在血液、尿液中的基质效应较弱，分别为-7.4%、-3.0%。该法无需衍生化处理，简便高效，灵敏度高，重复性好，适用于人体血液、尿液中氟乙酸的快速检测。     

液相色谱-串联质谱法测定液态乳制品中的苯代三聚氰胺

建立了液态乳制品中苯代三聚氰胺的高效液相色谱-串联质谱(HPLC-MS/MS)测定方法。优化了前处理条件、液相色谱和质谱参数。样品经LC-C18固相萃取柱富集净化后,采用ZORBAX Eclipse Plus C18色谱柱分离,流动相为乙腈-水(15∶85,体积比),流速为0.3 mL/min。采用正离子模式的电喷雾质谱检测,多反应(MRM)选择离子监测,定量离子与定性离子分别为m/z 104.1与m/z 146.0,外标法定量。结果表明,苯代三聚氰胺在2~100μg/L范围内线性关系良好,相关系数为0.999 1,方法的检出限和定量下限分别为1.0μg/kg和3.0μg/kg。在低、中、高3个加标水平下的平均回收率为77%~105%,相对标准偏差(RSD)为2.3%~5.0%。该方法操作简单、准确可靠,适用于液态乳制品中苯代三聚氰胺的测定。     

气相色谱-质谱联用法测定纺织品中2-正辛基-4-异噻唑啉-3-酮等5种防腐剂

建立了气相色谱-质谱联用法测定纺织品中2-正辛基-4-异噻唑啉-3-酮(OIT)、4-氯-3-甲基苯酚(PCMC),2,4,6-三溴苯酚(2,4,6-TBP),2,6-二甲基苯酚(2,6-DMP)、对苯基苯酚(PPP)等5种防腐剂的方法。样品采用甲醇超声提取,提取液浓缩定容后,经DB-5MS石英毛细管柱分离,进行气相色谱-质谱联用仪分析,全扫描定性,选择离子定量。OIT、2,4,6-TBP、2,6-DMP的线性范围为0.3~20μg/m L,r≥0.9991,检出限为0.3 mg/kg;PCMC,PPP的线性范围为0.15~10μg/m L,r≥0.9993,检出限为0.15 mg/kg。5种防腐剂的回收率为72.7%~110%,RSD≤8.4%(n=6)。     

免疫亲和柱净化-超高效亲水色谱-三重四极杆质谱联用法测定人尿液和血浆中河豚毒素

建立了测定人尿液和血浆中河豚毒素( TTX)的超高液相色谱-三重四极杆质谱联用分析方法。尿液和血浆样品经免疫亲和柱净化,以0.1%甲酸-乙腈和0.1%甲酸溶液作为流动相进行梯度洗脱,在UPLC BEH Amide柱上实现分离,正离子电喷雾多反应监测( MRM)模式检测,溶剂标准外标法定量。尿液和血浆中TTX的测量范围为0.05~400μg/L,平均加标回收率分别为92%~95%和91%~96%,相对标准偏差在3.3%~7.2%和3.9%~7.8%(n=5)之间,样品中 TTX的检出限(S/N=3)均为0.02μg/L,定量限(S/N=10)为0.05μg/L。本方法适用于尿液和血浆中TTX的中毒检测和临床监测。     

高效液相色谱-质谱法测定尿液中痕量雷公藤春碱

提出了尿液中雷公藤春碱的高效液相色谱-质谱测定方法。尿液样品经Waters Oasis(MCX固相萃取小柱富集、净化后,以Zorbax Eclipse SB C18反相色谱柱(4.6 mm×250 mm,5μm)为分离柱,以乙酸盐缓冲溶液-乙腈(40+60)为流动相,采用正离子模式大气压化学电离源,在选择离子监测模式下进行检测,雷公藤春碱的定量离子质荷比(m/z)为874.4。线性范围为0.2~50.0μg·L-1,检出限(3S/N)为0.07μg·L-1,测定下限(10S/N)为0.2μg·L-1。回收率在86.0%~92.0%之间,日内(n=6)和日间(n=15)相对标准偏差分别小于7.5%和10.5%。     

离子色谱-三重四极杆质谱法同时测定血浆和尿液中百草枯和敌草快

百草枯和敌草快是广泛使用的非选择性触杀型除草剂,中毒后会造成急性肺损伤,病死率高,同时监测血浆和尿液中百草枯和敌草快的浓度,可以为临床早期诊断和预后提供有价值的信息。血浆和尿液中百草枯和敌草快的主要检测方法为液相色谱-质谱法。百草枯和敌草快为强极性水溶性化合物,在反相色谱柱上难以保留,多采用离子对色谱法或亲水色谱法进行分离。采用离子对色谱法时,加入的离子对试剂有离子抑制作用,降低了质谱检测的灵敏度,还给质谱系统增加了额外的污染;亲水色谱法易受基质成分影响,保留时间不稳定。考虑到百草枯和敌草快在水溶液中以双电荷联吡啶离子状态存在,更适合采用阳离子交换色谱法,建立了离子色谱-三重四极杆质谱测定血浆和尿液中百草枯和敌草快的检测方法。血浆和尿液样品经水稀释后,直接过混合型聚合物反相吸附和弱阳离子交换固相萃取柱（Oasis WCX）净化,经IonPac CS 18型阳离子色谱柱（250 mm×2.0 mm,6.0 μm）分离,以自动在线产生的甲磺酸进行梯度洗脱,色谱柱流出液经阳离子抑制器抑制后进入质谱系统,在ESI⁺ 、多反应监测（MRM）模式下检测,稳定同位素内标法定量。百草枯和敌草快分别在1.0~150 μg/L和0.5~75 μg/L范围内线性关系良好,血浆中的平均基质效应分别为84.2%~89.3%和84.7%~91.1%,尿液中平均基质效应分别为50.3%~58.4%和51.9%~59.4%;血浆中百草枯和敌草快的平均加标回收率分别为93.5%~117%和91.7%~112%,相对标准偏差（RSD）分别为3.4%~16.7%和2.8%~13.2%;尿液中百草枯和敌草快的平均加标回收率分别为90.0%~118%和99.2%~116%,RSD分别为5.6%~14.9%和2.4%~17.3%（n =6）;血浆和尿液中百草枯和敌草快的检出限分别0.3 μg/L和0.2 μg/L,定量限分别为1.0 μg/L和0.5 μg/L。该法灵敏度高,准确性好,可用于血浆和尿液中百草枯和敌草快的中毒检测。     

液相色谱-串联质谱法测定液态乳制品中的苯代三聚氰胺

建立了液态乳制品中苯代三聚氰胺的高效液相色谱-串联质谱(HPLC-MS/MS)测定方法。优化了前处理条件、液相色谱和质谱参数。样品经LC-C18固相萃取柱富集净化后,采用ZORBAX-Eclipse Plus C18色谱柱分离,流动相为乙腈-水(15∶85,体积比),流速为0.3 mL/min。采用正离子模式的电喷雾质谱检测,多反应(MRM)选择离子监测,定量离子与定性离子分别为m/z 104.1与m/z 146.0,外标法定量。结果表明,苯代三聚氰胺在2~100 μg/L范围内线性关系良好,相关系数为0.999 1,方法的检出限和定量下限分别为1.0 μg/kg和3.0 μg/kg。在低、中、高3个加标水平下的平均回收率为77%~105%,相对标准偏差(RSD)为2.3%~5.0%。该方法操作简单、准确可靠,适用于液态乳制品中苯代三聚氰胺的测定。     

超高效液相色谱-串联质谱法测定水果中乙撑硫脲残留

建立了水果中乙撑硫脲(Ethylenethiourea,ETU)的超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。样品经碱性乙腈(1.5%氨水乙腈)振荡提取,弗罗里硅土净化后,以乙腈-0.2%甲酸为流动相,0.4m L/min流速下梯度洗脱,经HSS T3色谱柱分离,在正离子模式下采用多反应监测(MRM)扫描测定,外标法定量。研究表明,ETU在5~200μg/L质量浓度范围内线性关系良好,相关系数均大于0.999;5,20,50μg/L 3个加标水平下,苹果、桃、葡萄、柑橘和香蕉5种基质中乙撑硫脲的加标回收率分别为93.6%~101.4%,91.2%~98.4%,84.6%~95.1%,86.8%~97.9%和79.5%~96.3%;检出限分别为0.08,0.13,0.11,0.23,0.26μg/L;定量下限分别为0.28,0.42,0.37,0.75,0.86μg/L。该方法简便、准确、经济、环保,能够满足水果中乙撑硫脲残留的快速检测要求。     

在线固相萃取/液相色谱-串联质谱法快速检测全血及尿液中15种杀鼠药

建立了同时测定血液和尿液样品中15种杀鼠药的在线固相萃取/液相色谱-三重四极杆串联质谱(On-line SPE/LC-MS/MS)分析方法。用乙腈沉淀样品中的蛋白质,经稀释、离心、过滤后直接进样。通过在线固相萃取柱HLB富集纯化,以ZORBAX Eclipse Plus C18柱为分析柱,乙腈-0.01 mol/L乙酸铵水溶液为流动相进行梯度洗脱。采用电喷雾电离(ESI+/ESI-)快速正负切换模式,动态多反应监测模式(DMRM)扫描,外标法定量。结果表明,15种杀鼠药采用二次方程拟合时线性关系良好,血液中r~2≥0.997 8,尿液r~2≥0.996 5,方法的检出限和定量下限分别为0.10~5.00μg/L和0.50~10.0μg/L,3个添加水平下的回收率为81.8%~109.6%,日内相对标准偏差(RSD)为0.3%~3.6%,日间RSD为0.3%~3.8%(n=6)。该方法简单方便,灵敏度高,能够用以血液和尿液样品中15种杀鼠药的快速筛查和准确定量。     

Synthesis and structure of hydroxyisoxazolidines and derivatives of hydroxylamine and alkenals

The reactions of N-substituted hydroxylamines with alkenals serve as a method for the synthesis of the corresponding 2-substituted 3(5)-hydroxyisoxazolidines. The reaction pathway is determined by the nature of the substituent attached to the nitrogen atom. Ring-chain isomerism has been detected in these newly obtained compoundsTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1270–1276, September, 1987.     

红霉素9,11-亚胺醚和乙腈分子加合物的合成和晶体结构

通过控制红霉素A (E)肟的贝克曼重排反应条件合成了一种关键中间体红霉素9,11-亚胺醚, 该化合物可与乙腈形成稳定的分子加合物(摩尔比为1∶1), 未见文献报道. 阐述了该化合物的合成、晶体结构、晶体学数据和结构参数. 该化合物为无色透明晶体, 属单斜晶系, 空间群P2₁. 对该加合物和已知化合物红霉素6,9-亚胺醚晶体结构的对照解析, 有助于对重排反应机理、异构化机理和两异构体还原差异性的分析, 对重排反应和还原反应起到积极的指导作用.     

Ti-V基储氢合金及其氢化物的物相结构与组分优化设计

Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB₅型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。     

Sizes of atoms and ions and covalency of bonding in molecules and crystals

A new system of atomic radii for the elements up to barium inclusive is constructed. Values of the radii are chosen so as the dependence between the dissociation energy of diatomic homonuclear molecules and a depth of atom overlapping is monotonous, and the scatter of data is minimal. The depth of overlapping is calculated as a difference between the sum of atomic radii and an experimental interatomic distance. Conclusions are made that: the radii of free atoms and ions are determined by the value of the electron density equal to 0.01 au; they considerably change in molecules and crystals only as a result of the charge transfer from cation to anion; covalent bonding is well described by the overlapping of free atoms (ions), confined by the surface of the given radius, and its energy depends upon the depth of overlapping of valence electron densities of atoms. A method of overlapping atoms is proposed for the approximate estimation of ionic sizes and charges in bound systems.     

四环素-铕与卵磷脂的相互作用及卵磷脂的测定

以四环素(TC)-Eu3 作为荧光探针,提出了新的荧光光度法测量卵磷脂(PC)。在pH 5.7的酸度条件下,扫描不同浓度的PC与TC-Eu3 的荧光光谱。通过优化实验条件,得到了测定PC的最佳条件。卵磷脂能使TC-Eu3 位于612 nm处的特征荧光显著增强且增强的荧光强度与PC的量成正比。测量的线性范围为4.0×10-7~1.4×10-5mol/L,检出限为3.9×10-8mol/L。该方法已用于实际样品的测定。     

Ni(Ⅱ)和Zn(Ⅱ)的乙基黄原酸盐与吡啶碱配合物的合成及性质的研究

乙基黄原酸基的结构为:(简写为Exan,它是一个双齿配体,能和许多金属离子形成稳定配合物。 本文依据实验结果,对3种Ni(Ⅱ)和2种Zn(Ⅱ)的乙基黄原酸盐混合配合物的性质作一些系统的比较.应用红外光谱讨论这些混合配合物的C—O及C—S键振动频率位移;用热谱讨论它们的热稳定性及失重过程的变化;通过组成分析用电子光谱及磁学方     

Synthesis and Characterization of Chloralose-Derived Thiosemicarbazones and Semicarbazones and Investigation of Their Antimicrobial Properties

Thiosemicarbazones(7–10)/semicarbazones(11–14) were synthesized in good yields via the condensation of α-gluco-, β-gluco-, galacto-, manno- chloralose derived 1,4-furanodialdoses (1-4) with thiosemicarbazide(5)/semicarbazide(6). The structures of all products were characterized by FTIR, NMR spectroscopic methods and elemental analysis. The compounds have been found to display moderate antimicrobial activity against Gram-positive, Gram-negative bacteria and antifungal activity against a Candida albicans. MIC values of the compounds range from 260 to 1510 μg/mL.     

Resurrection and Reactivation of Acetylcholinesterase and Butyrylcholinesterase

Organophosphorus (OP) nerve agents and pesticides present significant threats to civilian and military populations. OP compounds include the nefarious G and V chemical nerve agents, but more commonly, civilians are exposed to less toxic OP pesticides, resulting in the same negative toxicological effects and thousands of deaths on an annual basis. After decades of research, no new therapeutics have been realized since the mid-1900s. Upon phosphylation of the catalytic serine residue, a process known as inhibition, there is an accumulation of acetylcholine (ACh) in the brain synapses and neuromuscular junctions, leading to a cholinergic crisis and eventually death. Oxime nucleophiles can reactivate select OP-inhibited acetylcholinesterase (AChE). Yet, the fields of reactivation of AChE and butyrylcholinesterase encounter additional challenges as broad-spectrum reactivation of either enzyme is difficult. Additional problems include the ability to cross the blood brain barrier (BBB) and to provide therapy in the central nervous system. Yet another complication arises in a competitive reaction, known as aging, whereby OP-inhibited AChE is converted to an inactive form, which until very recently, had been impossible to reverse to an active, functional form. Evaluations of uncharged oximes and other neutral nucleophiles have been made. Non-oxime reactivators, such as aromatic general bases and Mannich bases, have been developed. The issue of aging, which generates an anionic phosphylated serine residue, has been historically recalcitrant to recovery by any therapeutic approach—that is, until earlier this year. Mannich bases not only serve as reactivators of OP-inhibited AChE, but this class of compounds can also recover activity from the aged form of AChE, a process referred to as resurrection. This review covers the modern efforts to address all of these issues and notes the complexities of therapeutic development along these different lines of research.     

Interaction and Stability of Mixed Micelle and Monolayer of Nonionic and Cationic Surfactant Mixtures

Interaction and stability of binary mixtures of cationic surfactants hexadecyltrimethylammonium bromide (HTAB) or hexadecylpyridinium bromide (HPyBr) with nonionic surfactant decanoyl-N-methyl-glucamide (Mega-10) have been studied at different mole fraction of cationic surfactants by using interfacial tension measurements and fluorescence probe techniques. From interfacial tension measurements, the critical micellar concentration and various interfacial thermodynamic parameters have been evaluated. The experimental cmc's were analyzed with the pseudophase separation model, the regular solution theory, and the Maeda's approach. These approaches allowed us to determine the interaction parameter and composition in the mixed state. By using the static quenching method, the mean micellar aggregation numbers of pure and mixed micelles of HTAB + Mega-10 were obtained. It has been observed that the aggregation number of mixed micelles deviates negatively from the ideal behavior. The micropolarity of the micelle was monitored with pyrene fluorescence intensity ratio and found to be increase with the increase of ionic content. The polarization of fluorescence probe Rhodamine B was monitored at different mole fraction of cationic surfactants.