废旧电池中铜锌锰及氯化铵的分离和利用

为探寻简便有效途径解决废旧电池对环境的污染以及对人体健康危害的问题,在实验中选取常用的锌锰干电池为研究对象,通过酸解、沉淀、氧化还原分别对锌和锰及少量氯化铵进行回收处理,制取七水合硫酸锌和二氧化锰及氯化铵。     

铋膜电极电位溶出法测定痕量铅、镉、锌

研究了用铋膜电极替代汞膜电极测定痕量重金属元素铅、镉和锌的电位溶出法。实验了同位镀铋膜及测定重金属特别是痕量铅的条件。实验结果表明：铅、镉、锌在铋膜电极上可得到灵敏的电位溶出峰，峰高和溶出电位与汞膜电极法相近，使用铋膜电极可避免使用汞电极带来的环境污染。利用铋膜电极电位溶出法测定了水样及血样中痕量铅的含量。     

极谱法同时测定海水中的铜、镉、铅、锌

建立极谱法同时测定海水中铜、镉、铅、锌的含量。在10.0～35.0℃条件下,试样于–1.15 V恒压下电解,富集在汞电极上生成汞齐,并随电极电位的变化而发生氧化还原反应,产生电流,通过标准加入法进行定性和定量。铜、镉、铅、锌的检出限分别为0.64,0.14,0.17,2.0μg/L,定量限分别为2.5,0.50,0.50,10.0μg/L。样品加标回收率为80.4%～106.0%,测定结果的相对标准偏差为0.43%～6.09%(n=6)。该法具有操作简便、抗干扰性能强、灵敏度高等特点,能够满足海水中铜、镉、铅、锌的监测要求。     

电感耦合等离子体质谱法同时检测红枣中铅、砷、镉、汞、铜、锌和16种稀土元素

为了研究哈密、若羌和和田红枣中铅、砷、镉、汞、铜、锌和16种稀土元素的含量情况,了解红枣重金属及稀土元素摄入的风险,建立同时检测红枣中铅、砷、汞、铜、锌和16种稀土元素的方法。红枣样品用微波消解法进行样品前处理,以电感耦合等离子体质谱法测定红枣中铅、砷、镉、汞、铜、锌和16种稀土元素的含量。各元素校准曲线的相关系数均大于0.999 0,检出限为0.01~0.05μg/L。加标回收率为92.1%~105.2%,测定结果的相对标准偏差为1.2%~3.6%(n=6)。用该方法测定苹果标准物质(GBW 10019),测定值与标准值一致。该方法适用于红枣类样品中多元素污染物快速检测及风险评估,红枣样品分析结果表明铅、砷、镉、汞、铜和稀土元素在3种红枣中的含量较低,风险监测数据表明红枣中存在重金属铅、镉摄入性风险。     

电感耦合等离子体发射光谱(ICP－OES)法测定聚碳酸酯中重金属铅、镉、汞、铬

采用微波消解法对聚碳酸酯(PC)样品进行前处理,使用电感耦合等离子体发射光谱(ICPOES)法测定聚碳酸酯中重金属铅、镉、汞、铬元素,通过对消解方式和消解试剂的研究,建立了ICP-OES法测定聚碳酸酯中重金属铅、镉、汞、铬元素的方法。结果表明,铅、镉、汞、铬加标回收率均在94.0%～105%,相对标准偏差(RSD)均小于4%,样品处理时间短,测定速度快,污染小,环保,有较高的加标回收率和精密度,适用于聚碳酸酯中重金属铅、镉、汞、铬的测定。     

ICP-OES法同时测定功效牙膏中10种元素

采用ICP-OES同时测定功效牙膏中的铅、镉、汞、砷、铜、锌、钾、锶、银、钛等10种元素。结果表明,在HNO3-H2O2-HF体系下,采用微波消解方法,对牙膏样品进行完全消解。通过优化仪器条件参数,实现对功效牙膏中的铅、镉、汞、砷、铜、锌、钾、锶、银、钛等元素的ICP-OES法同时测定。钛、钾元素质量浓度在5.0~100.0 mg/L,锶、锌元素质量浓度在1.0~50.0 mg/L,铅、镉、汞、砷、铜、银元素质量浓度在0.1~2.0 mg/L范围内时,方法有良好的线性关系,相关系数均大于0.992。样品中各元素的加标回收率在93.0%~109.0%。     

ICP-AES法测定进口铜精矿中有害元素

研究了ICP-AES法测定进口铜精矿中铅、锌、钴、镍、镁、镉、砷、锑、铋、汞的含量，采用测定标样、加标回收试验，并与AAS方法比较和参加全国水平测试等多种方法对该方法进行考察，证明该方法准确可靠、简便快速，可用于进口铜精矿的快速检验。     

75—3A型汞膜电极快速极谱仪

厦门大学化学系与厦门第二分析仪器厂试制成功75-3A型汞膜电极快速极谱仪。该仪器应用集成电路装置。仪器包括线性扫描电路、电极系统和记录电流部分。用两只运算放大器作为线性扫描电路和电流放大器。铂球镀银沾汞的汞膜电极代替滴汞电极作常规极谱分析,也可用为溶出分析。用此种电极和仪器在有关单位按常规极谱分析已用于铜合金中的铅和锌,矿物中的铜、铅、镉和锌,铝合金中铋、铜和铅的测定;借溶出法已用于海水痕量铜、镉和锌,二氧化锆中痕量铜、     

微波消解-电感耦合等离子体质谱(ICP-MS)法同时测定土壤中8种重金属元素

采用微波消解-电感耦合等离子体质谱法同时测定土壤中砷、镉、铬、铜、汞、镍、铅、锌8种痕量元素,对质谱干扰和非质谱干扰进行了校正。8种重金属元素在一定的质量浓度范围内与其信号强度呈线性关系,方法的检出限(3s)在0.001 2~0.029μg/L。用加标回收测定其回收率,加标回收率范围在90.0%~96.3%,对土壤样品平行测定6次,测定值的相对标准偏差在2.1%~3.0%。对湛江南柳河附近土壤进行重金属监测,监测结果符合标准要求。     

微波消化-在线固相萃取富集高效液相色谱法测定饲料用灌木中痕量铅镉汞

研究了用微波消化样品,WatersXterraTMRP18(3.9mm×20mm)色谱柱在线固相萃取富集,二极管矩阵检测器检测,高效液相色谱测定饲料用灌木中痕量铅、镉、汞的方法。铅、镉和汞含量在0.1～100μg·L-1范围内与峰面积呈线性关系,方法检出限(S/N=3)为:铅2.0ng·L-1,镉1.5ng·L-1和汞2.0ng·L-1,方法相对标准偏差为2.0%～3.1%,标准回收率为94%～103%,该方法用于测定饲料用灌木中低含量的铅、镉、汞,结果满意。     

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.