气相色谱法测定禽蛋中微量有机氯农药及多氯联苯的残留

建立了以正己烷振荡提取，以及PCB2和PCB209为内标的快速检测禽蛋中微量有机氯污染物的气相色谱法。与传统的索氏提取法相比，在保证足够的准确度，精确度和灵敏度的前提下，具有前处理简单，测试成本低，标本用量少的特点。而且可同时测定有机氯农药和典型的多氯联苯类化合物的残留，特别适于检测食品中的微量有机污染物。用该方法测试的结果表明，标准全蛋粉添加ng/g级待测物时，各种待测物的回收率为84．31％－116．77％（3次测定平均值）；相对标准偏差为6％－18％（7次测定平均值）；最低检出量为0.07ng/g-0.35ng/g。中国部分城市市售鸡蛋中的有机氯农药以p,p'-DDE的检出量最高，p,p'-DDT次之；多氯联苯的检出量很低，大多数样品中多氯联苯的总检出量低于10ng/g。在所检出的多氯联苯中，绝大部分为含氯低的（氯原子数为3－5）的氯化物。     

基质固相分散-加速溶剂萃取-气相色谱法测土壤中有机氯农药残留

建立了用弗罗里硅土作基质固相分散剂的加速溶剂萃取、并以灭蚁灵（Mirex）为内标的快速、同时测定土壤中16种有机氯农药的气相色谱法。加速溶剂萃取仪在100℃,10．3Mpa用正己烷和丙酮（1：1,V／V）静态提取样品10min,0．01μg/g加标水平回收率为77．3％-101．3％;方法检出限为0．01—0．04ng／g。方法满足了土壤中有机氯农药残留测定的要求。对我国南方不同地域的72个土壤样品进行了测定,大部分有机氯农药在土壤中都有一定检出量,其中环氧七氯最高（2．6～844．5ng／g）,甲氧DDT（23．2—219．8ng／g）和P,P’-DDT（4．0—183．1ng／g）次之,而o,P＇-DDT在72个土样中都没有检出。     

牡蛎中痕量有机氯农药残留量的分析方法研究

建立了同时测定牡蛎中16种有机氯农药残留量的前处理方法和气相色谱分析方法。在100℃的温度条件下,用加速溶剂提取（ASE）提取样品中的有机氯农药,用凝胶渗透色谱（GPC）结合Florisil柱净化,以RTX-5MS毛细管色谱柱分离、ECD检测器测定。结果表明,样品的加标回收率（n=3）为81％～110％,方法检出限为0．2～0．7ng／g,样品检测的相对标准偏差为2．9％～15．2％。     

微波萃取-全自动凝胶色谱净化-气相色谱法同时测定太湖沉积物中多氯联苯和有机氯

建立了沉积物中多氯联苯和有机氯农药等39种持久性有机污染物的同时测定方法。样品用正己烷和丙酮(体积比为1∶1)进行微波提取,提取溶液经凝胶色谱和弗罗里硅土净化,浓缩后采用气相色谱法测定。回收率在68.8%~84.2%,检出限为0.05~0.25ng/g。方法适用于沉积物样品中多种多氯联苯和有机氯农药含量的同时测定。     

毛细管气相色谱法测定水果、蔬菜中17种有机氯农药的残留量

采用毛细管气相色谱法测定水果、蔬菜中17种有机氯农药的残留量。用丙酮-正己烷混合液(1：1)提取样品中的有机氯农药,将提取液浓缩后,经过弗罗里硅土层析柱净化,用HP-5毛细管柱分离,再以电子捕获检测器测定,外标法定量。方法的加标回收率为80．7％-113．1％,测定结果的相对标准偏差为9％-17％,检出限为0．5—8．0ng／g。     

毛细管气相色谱法同时测定水产品中的多氯联苯和有机氯农药残留量

建立了毛细管气相色谱法同时测定水产品中多氯联苯和有机氯农药的方法，用高氯酸与冰乙酸的混合溶液消化样品，以石油醚提取，浓硫酸净化后，用毛细管气相色谱法测定，方法的回收法为88％－110％，相对标准偏差为8％－19％（n=6)，检出限为0．08－0．60ug/kg，方法简便，快速，结果准确。     

土壤中多种有机氯及拟除虫菊酯类农药的GC-ECD测定

气相色谱法同时测定土壤中多种有机氯及拟除虫菊酯类农药。对土壤的分析结果：有机氯农药的检出限0．001～0、003μg／mL，拟除虫菊酯类农药检出限0.008～0．02μg／mL，线性相关系数0．9978～0．9999。用y（石油醚）：V（丙酮）=3：1超声波提取，有机氯农药回收率94．2％～124．0％，相对标准偏差为3．3％～8．8％（n=5）；拟除虫菊酯类农药回收率95．2％～118．3％，相对标准偏差为5．7％～7．1％（n=5）；方法适用于土壤样品中农药残留测定。     

大口径毛细管气相色谱法测定油脂、果蔬中20种有机氯农药的残留量

 对水果、蔬菜样品采用混合溶剂提取 ,对油脂样品则采用乙腈分配处理 ,然后运用柱色谱净化方式 ,以HP 1 0 1大口径弹性石英毛细管柱为分离柱 ,以电子捕获检测器检测 ,用气相色谱法测定油脂、水果、蔬菜中 2 0种有机氯农药的残留量。方法的检测限为 1 .0ng/g～ 2 0 .0ng/g ,回收率为 83.2 %～ 1 0 6.8% ,RSD为 2 .0 %～9.5%。     

基于全二维气相色谱-四极杆飞行时间质谱法同时检测土壤中24种有机磷与20种有机氯农药残留

基于全二维气相色谱－四极杆飞行时间质谱（GC × GC－Q－TOF MS）建立了土壤样品中24种有机磷 和20种有机氯农药残留的快速同时检测方法,样品经索氏提取后直接采用全二维气相色谱进行分离,有效实 现了杂质与目标物的完全族分离效果。以24种有机磷和20种有机氯农药的高分辨精确质量特征离子进行定 量分析,结果表明,44 种农药均在 20～3 000 μg/L 质量浓度范围内呈线性关系,相关系数（r 2 ）为 0. 990 3～ 0. 999 9,检出限（LOD）为 0. 3～7. 9 μg/L;方法的平均回收率为 93. 0%,平均相对标准偏差（RSD,n = 5）为 6. 9%。该文可为土壤中农药残留的高通量快速筛查提供方法参考。     

亚临界水萃取及气相色谱-串联质谱法检测红茶中多种农药残留

建立了亚临界水萃取及气相色谱-串联质谱(GC-MS/MS)检测红茶中21种有机氯和拟除虫菊酯农药残留的方法。在萃取压力为5 MPa条件下,样品经150 ℃的亚临界水提取15 min后,将目标物转移至丙酮-正己烷(1:1, v/v)中,经ENVI-Carb固相萃取净化小柱净化,DB-5毛细管气相色谱柱分离,在多反应监测(MRM)模式下进行MS/MS检测,基质匹配溶液内标法定量。各目标物在5.0～320.0 μg/L范围内线性关系良好,相关系数均大于0.99,其定量限(信噪比(S/N)＞10)为50 ng/g,检出限(S/N＞3)为10 ng/g。茶叶基质中添加50、100和200 ng/g的标准品时,21种农药的回收率为70.18%～119.98%,相对标准偏差(RSD)为5.01%～11.76%。该方法的灵敏度、准确度和精密度均符合农药残留测定的技术要求,适用于红茶中有机氯和拟除虫菊酯农药残留的检测。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.