Ag-Fe复合氧化物催化剂的结构及还原性能

采用共沉淀法制备了ＡｇＦｅ复合氧化物催化剂．用ＸＲＤ研究了不同Ａｇ含量催化剂的结构变化情况,利用程序升温还原技术（ＴＰＲ）考察了热处理温度对催化剂还原性能的影响．结果表明：不同Ａｇ含量催化剂的还原能力与σＡｇＦｅＯ２晶相生成情况有对应关系,催化剂的氧活性主要来源于分散在其表面晶粒较小的σＡｇＦｅＯ２物种．     

茶水中多元素化学形态的同时分析

本工作建立了分离和测定茶水中Ａｌ、Ｍｎ、Ｍｇ、Ｚｎ及Ｆｅ的化学形态的方法。茶水中金属元素的各化学形态经高效液相色谱分离后，用电感耦合等离子体原子发射光谱在线检测Ｍｎ、Ｍｇ、Ｚｎ、Ｆｅ，用石墨炉原子吸收非在线测定Ａｌ。结果表明，茶水中Ａｌ等金属元素一部分以无机离子形式存在，另一部分则以有机络合物形式存在。实验发现当以Ａｌ、Ｍｎ、Ｍｇ、Ｚｎ、Ｆｅ儿茶素络合物作为标准物质时，ＨＰＬＣ的保留时间恰好与茶水     

链状三核异金属簇阴离子［Cl_2FeS_2M＇（PPh_3）_2］~－（M＝Mo

在５５０～９０ｃｍ~（－１）波数范围内，测量簇阴离子［Ｃｌ_２ＦｅＳ_２ＭＳ_２Ｍ′（ＰＰｈ_３）_２］~－（Ｍ＝Ｍｏ，Ｍ′＝Ａｇ；Ｍ＝Ｗ，Ｍ′＝Ｃｕ，Ａｇ）的付里叶变换红外光谱，并对标题簇阴离子［Ｃｌ_２ＦｅＳ_２ＷＳ_２Ｃｕ（ＰＰｈ_３）_２］~－，［Ｃｌ_２ＦｅＳ_２ＭｏＳ_２Ａｇ（ＰＰｈ_３）_２］~－和［Ｃｌ_２ＦｅＳ_２ＷＳ_２Ａｇ（ＰＰｈ_３）_２］~－骨架的振动光谱给予经验指认。同时采用＂诱导自洽方法计算振动力常数＂程序，对簇骨架［Ｃｌ_２ＦｅＳ_２ＭＳ_２Ｍ~′Ｐ_２］进行简正坐标分析。振动频率的计算值与观测值符合良好，两者平均偏差小于１．０％，计算结果支持了振动谱带的归属并表明计算力常数的合理性。文中还讨论了主要价键振动频率的变化规律。     

添加Al、Mg、W、Mo对烧结Nd-Fe-B磁体磁性能与显微组织的影响

研究了在烧结ＮｄＦｅＢ磁体晶间添加Ａｌ、Ｍｇ、Ｗ、Ｍｏ等合金元素对显微组织和磁性能的影响。实验结果表明：低熔点合金元素Ａｌ、Ｍｇ能显著提高ＮｄＦｅＢ磁体的矫顽力，略微降低剩磁，对磁体的热稳定性无影响；高熔点合金元素Ｗ、Ｍｏ在不降低剩磁的情况下亦能提高磁体的矫顽力，但效果不如Ａｌ、Ｍｇ明显。显微组织分析表明，在添加低熔点和高熔点合金元素的磁体晶间发现了两种不同的新相。矫顽力的提高可归于晶间新相的出现。进一步分析表明，与传统的合金化相比，对ＮｄＦｅＢ磁体晶间区域进行微合金化是改进ＮｄＦｅＢ磁体组织与性能的一种更为有效的手段。     

助催化剂对Fe1-xO基氨合成催化剂还原性能的影响

当助催化剂存在是地，Ｆｅ１－ｘＯ基催化剂的还原性能明显优于Ｆｅ３Ｏ４基催化剂，其原因是铝、钾、钙的氧化物对催化剂母体相Ｆｅ１－ｘＯ和Ｆｅ３Ｏ４还原性能的影响不同。由于Ａｌ＾３＋大量地进入Ｆｅ３Ｏ４的晶格而强烈地阻止Ｆｅ３Ｏ４的还原，只有少量的Ａｌ＾３＋能进入Ｆｅ１－ｘＯ晶格，因此对Ｆｅ１－ｘＯ的还原影响很小；     

活性碳纤维ZCSACF的制备及其氧化还原吸附性能

用ＺｎＣｌ２溶液浸泡剑麻纤维，然后高温处理而制备出海拔恶性循环碳纤维ＺＣＳＡＣＦ，借助于ＡＡＳ＜ＷＡＸＤ，ＳＥＭ和ＩＲ探讨了ＸＣＳＡＣＦ对贵金属离子的氧化还原吸附行为。实验结果表明与水汽活化的ＳＡＣＦ相比，ＺＣＳＡＣＦ可在较低的温度下，第八是度高，并对贵金属离子具有较高的吸附量，可以认为，ＺＣＳＡＣＦ比ＳＡＣＦ具有更多更强的还原性基团。ＺＣＳＡＣＦ的氧化还原吸附能力受制备工艺。如处理温度和Ｚｎｃｌ     

几种尖晶石型氧化物纳米粉体的制备及气敏性

采用化学共沉淀法合成了４种尖晶石型复合氧化物ＭＦｅ２Ｏ４（Ｍ＝Ｃｕ＾２＋，Ｚｎ＾２＋，Ｃｄ＾２＋，Ｍｇ＾２＋），Ｘ射线粉末衍射分析，透射电镜及比表面测定等表征结果表明它们均具较大比表面积的纳米粉体，平均粒径〈５０ｎｍ，将样品做成厚膜型气敏元件，测定了其对乙炔，液化石油气，一氧化碳、氢气和乙醇等还原（可燃）性气体的气敏特性。     

非晶态Fe-Al-P-O催化剂的制备与表征

采用溶胶凝胶法制备了非晶态Ｆｅ－Ａｌ－Ｐ－Ｏ催化剂,并用ＩＲ,ＸＲＤ,ＴＥＭ,ＢＥＴ,ＴＲＰ等技术对其物相组成、结构,表面形貌和活性氧量进行了表征。结果表明,非晶态Ｆｅ－Ａｌ－Ｐ－Ｏ催化剂是由ＦｅＰＯ４和ＡｌＰＯ４组成的均一混合物,其比表面大于２００ｍ＾２／ｇ。纳米级颗粒分布,活性氧还原温度集中于４００￣５００℃间,是一种潜在的烷烃选择氧化催化剂。     

水蒸汽对负载型催化剂丙烷脱氢性能的影响：Ⅰ.反应性能的研究

研究了ＭｇＡｌ２Ｏ４，ＺｎＡｌ２Ｏ４负载的Ｐｔ－Ｓｎ催化剂在氮气及水蒸汽中的丙烷脱氢性能。考察了还原温度，反应温度，催化剂载量对Ｐｔ－ＳＳｎ／ＭｇＡｌ２Ｏ４催化剂丙烷脱氢性能的影响。     

用中子活化分析法研究25种元素在人体肝脏亚细胞组分中的分布

采用差速离心分离技术与中子活化分析法（ＮＡＡ）相结合的方法分析了人肝２５５中元素,并用标准参考物保证结果的准确性。分析结果表明,大多数元素在各亚细胞组分中并非均匀分布。Ａｓ、Ａｕ、Ｃｏ、Ｉ、Ｍｇ、Ｓｂ、Ｓｅ在细胞核和线粒体浓度最高。Ａｌ、Ｓｓ、Ａｕ、Ｂａ、Ｆｅ、Ｉ、Ｍｇ、Ｍｏ、Ｓｂ、Ｓｃ在细胞核和线粒体浓度最高。Ａｌ、Ａｓ、Ａｕ、Ｂａ、Ｆｅ、Ｉ、Ｌａ、Ｍｇ、Ｍｎ、Ｓｂ、Ｓｅ在胞液中深度最低,生物体     

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%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

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.     

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.     

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.     

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.     

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.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.