氮氧自由基研究（ⅩⅩⅢ）——哌啶氮氧自由基及其氧铵盐与N，N，N′，N′—

ESR波谱和流动－停止UV动力学研究表明，水溶液中2，2，6，6－四甲基－4－羟基哌啶－1－氧自由基1和相应氧铵溴盐2均可将N，N，N′，N′－四甲基对苯二胺（TMPD）氧化为相应自由基正离子TMPD^＋，2还能将TMPD^＋进一步氧化为二价正离子TMPD^2＋。TMPD^＋可发生可逆歧化，其稳定性强烈受介质酸碱性的影响，利用计算机对动力学曲线的模拟测得上述有关反应的速率常数，并讨论了反应机理。     

氮笼N12的量子化学研究

采用量子化学从头算方法研究了7个氮笼N₁₂,其中包括以前文献中研究过的两个氮笼N₁₂.在RHF/6-31G^*理论水平下进行全构型优化、振动频率分析和热化学计算.计算结果表明,7个结构均是势能面上的局域极小点.N₁₂(D_3d)是所有7个笼状异构体中最稳定的.能量分析表明,如果这些分子能够被合成,将会成为潜在的高能量密度材料.     

希夫碱N,N′-双水杨醛缩连氮的合成与晶体结构研究

由水杨醛与水合肼反应生成希夫碱N ,N′ 双水杨醛缩连氮 ,并用溶液法生长其单晶。X 射线单晶结构分析表明 ,此晶体属于单斜晶系 ,P2 ( 1) /n空间群 ,晶胞参数为 :a =8.4 97( 4 ) ,b =6 .2 90 ( 3) ,c =11.789( 5 ) ,β=10 7.874 ( 7)° ,V =5 99.6 ( 4 ) 3 ,Z =2 ,Dc =1.331g·cm-3 ,F ( 0 0 0 ) =2 5 2 ,结构偏离因子R =0 .0 4 6 9,wR2 =0 .110 8。晶体中一个分子羟基上的氧原子与另一个分子中 -CH =N -上的氢原子之间形成分子间氢键 (O┄H -C)。     

N,N,N＇,N’-四丁基丁二酰胺萃取Tb（Ⅲ）的研究

国内外在四取代双酰胺类萃取剂萃取铀（Ⅳ）、钍（Ⅳ）的性能研究方面已经做了大量工作，但对核废料中共存稀土元素的萃取研究较少。本文合成了N，N，N’，N’-四丁基丁二酰胺（TBSA），详细研究了其萃取Tb（Ⅲ）的性能。     

N, N, N′, N′-四丁基丙二酰胺萃取Pr3+的研究

利用丙二酸二乙酯与二正丁胺反应高收率的制备了N，N，N′，N′-四丁基丙二酰胺(TBMA)萃取剂。研究了硝酸浓度、硝酸锂浓度、萃取剂浓度以及温度等对萃取Pr(Ⅲ)分配比的影响，确定了萃合物的组成，得到了不同稀释剂中萃取反应的热力学数据。结合红外光谱和摩尔电导数据初步推断了萃合物的结构。     

Mo2N的表面性质和加氢脱氮活性

以XRD、H2－TPD、TPS方法研究了钝化和硫化处理对Mo2N体相结构和表面性质、以及对吡啶加氢脱氮（HDN）催化活性的影响。Mo2N经钝化或在673K硫化后，虽然其体相结构不发生变化，但其表面性质却发生了明显的异变，并伴随其加氢脱氮活性的显著降低．由Mo2N在不同钝化条件下生成的部分氧化产物以及H2－TPD结果，推测在缓慢钝化条件下，Mo2N表面钝化层为MoO2根据Mo2N硫化后的H2－TPD和相应HDN活性变化，以及Mo2N的TPS结果，认为Mo2N经673K硫化后其表面结构发生了硫化异变．     

N,N,N′,N′-四丁基丙二酰胺萃取Yb(Ⅲ)的研究

取代酰胺类萃取剂易合成、分解产物易除去可用于萃取铀 (Ⅳ )、钍 (Ⅳ ) [1 - 4 ] ,但对高放废液中共存稀土元素的萃取研究较少[5] 。本文在以前研究工作的基础上[6] ,进一步探讨了TBMA萃取Yb(Ⅲ )的性能。1　实验部分1 1　试剂和仪器试剂均为AR级。TBMA由实验室合成 ,减压蒸馏提纯 ,经元素分析、红外光谱等检验产品为目标产物 ,纯度高于 98%。FTS 1 65红外光谱仪 (美国Bio Rad公司 ) ,75 2分光光度计 (上海分析仪器总厂 ) ,PHS 2C精密数显酸度计 (上海伟业仪器厂 ) ,恒温康氏振荡器 (实验室改装 )。1 2　实验准确称量 1 970 3g…     

EFFECT OF N,N,N’,N’-TETRAALKYL TEREPHTHALAMIDE ON NON-ISOTHERMAL CRYSTALLIZATION KINETICS OF POLYPROPYLENE

The effect of N,N,N＇,N＇-tetraalkyl terephthalamide （TATA） on the non-isothermal crystallization and melting characteristics ofpolypropylene （PP） was studied. The addition of TATA can lead to the formation ofβ-crystal PP. With the increase in TATA concentration the degree of crystallinity for β-crystal PP increased significantly, and that for a-crystal PP decreased, which indicated that TATA effectively induced the formation of β-crystal PP. WAXD also revealed the existence of β-crystal PP after the introduction of TATA into PP. PP containing TATA crystallized at a temperature range of 5-10℃ higher than that of pure PP, and the half-crystallization time （t1/2） and Avrami exponent （n） of PP at the same cooling rate were decreased by the addition of TATA, indicating that TATA influenced the crystallization rate and crystallization growth mode of PP. The rate constant of crystallization of PP containing TATA （Zc） was larger than that of pure PP, which further indicated that the crystallization of PP was accelerated by the addition of TATA.     

N，N，N′，N′-四丁基丙二酰胺从硝酸盐介质中萃取铈(Ⅲ)

Study on the extraction and separation of rare earth with new extractants is important in the rare earth chemistry and nuclear reprocessing. In this work， the extraction of Ce(Ⅲ) with N，N，N′，N′-tetrabutylmalonamide (TBMA) in toluene from nitrate media has been investigated. The effect of the concentration of nitric acid， TBMA and salt-ing-out agent (LiNO₃) and also the temperature on the distribution ratios was examined. The stoichiometries of the extracted complexes were determined to be Ce(NO₃)₃·3TBMA and Ce(NO₃)₃·4TBMA， respectively. The ap-parent extraction constants and the enthalpy of the extraction were calculated based on the extraction data， which are logK_ex1=3.97， logK_ex2=4.75 and Δ_rH_m^?=-31.25kJ·mol^-1， respectively. The IR spectra of the loaded organic phase supported the suggested extraction mechanism.     

A Facile and Efficient Synthesis of N,N—Dimethylarylamines from Aryl Bromides

Catalytie amination of aryl bromides with in situ generated dimethylamines from N,N-dimethylacetamide(DMA)has been suceessfully carried out using Ni(phen)Cl2 as catalyst,Both electron-rich and electron-poor aromatie system reaeted smoothly under the conditions to give N,N-dimethylarylamines in good yields.     

上游水库水体中氨氮、亚硝酸盐氮、硝酸盐氮、总氮的测定和关系探究

采用紫外分光光度法测定上游水库固定监测点位近两年采集样品的总氮、硝酸盐氮、氨氮、亚硝酸盐氮含量.对测试结果进行分析比较,探讨了上游水库水中总氮、硝酸盐氮、氨氮、亚硝酸盐氮的关系,从而为上游水库水质数据分析和综合评价提供一定参考.     

Fixation of Atmospheric Nitrogen: Synthesis of Heterocycles with Atmospheric Nitrogen as the Nitrogen Source

Dry air is the source of molecular nitrogen for reactions with TiL₄, Li, and TMSCl (L = Cl, OiPr; TMS = trimethylsilyl). The nitrogen–titanium complexes thus prepared can be used to synthesize indoles, pyrroles, and lactams from carbonyl compounds. Applying this method to 1 provides access to 2 , the key compound in the synthesis of (±)-lycopodine.     

氮之琐谈

氮元素是空气的主要成分,也是构成有机化合物的重要元素;生命离不开氮元素,化学工业也需要众多含氮化合物作为基础的工业原料。地球上氮元素的循环起始于闪电或生物固氮,而发展节能高效的固氮方法依然是化学家的长期任务。氮氧化物如一氧化氮和二氧化氮等是重要的空气污染源,控制其排放是治理空气污染的重要途径。对含氮有机化合物如氨基酸与蛋白质的研究至关重要,有望为人类揭示生命的奥秘或提供重要的材料如尼龙等。     

Nitrogen Oxide Fluorides

Oxyfluorides of nitrogen, i.e. compounds containing the grouping F? N? O, have been known for many years in the form of simple compounds, such as NOF and NO₂F. Detailed studies of physical, structural, and chemical aspects of this class of compounds have been conducted only in recent years, after the potential of N? F compounds as rocket propellants had been recognized. Several novel types of oxyfluorides of nitrogen, such as difluorohydroxyl amines, RO? NF₂, or trifluoroamine oxide, F₃NO, have been discovered recently. A further major development in O? N? F chemistry is indicated by the discovery that compounds of great chemical potential are formed between HF and NOF or NO₂F, respectively. The compound O₂NOF, although not an oxyfluoride of nitrogen, will also be discussed in this review, because of its particular chemical relationship to NO₂F.     

A Nitrogen Battery Electrode involving Eight-Electron Transfer per Nitrogen for Energy Storage

Redox flow batteries have been discussed as scalable and simple stationary energy storage devices. However, currently developed systems encounter less competitive energy density and high costs, restricting their wider application. There is a lack of appropriate redox chemistry, preferably based on active materials that are abundant in nature and show high solubility in aqueous electrolytes. A nitrogen-centered redox cycle operating between the limiting species ammonia and nitrate via an eight-electron redox reaction stayed practically unnoticed, albeit its ubiquity in biological processes. Ammonia or nitrate are world-scale chemicals with high aqueous solubility, and are then comparably safe. We demonstrate here the successful implementation of such a nitrogen-based redox cycle between ammonia and nitrate with eight-electron transfer as a catholyte for Zn-based flow batteries, which continuously worked for 12.9 days with 930 charging-discharging cycles. A very competitive energy density of 577 Wh L⁻¹ can be reached, which is well above most reported flow batteries (e.g. 8 times the standard Zn-bromide battery), demonstrating that the nitrogen cycle with eight-electron transfer can offer promising cathodic redox chemistry for safe, affordable, and scalable high-energy-density storage devices.     

Nitrogen heterocycles from trimethylbenzenes

The reaction between 1,2,4‐trimethylbenzene 1 , isobutyric aldehyde, and cyanoacetic ester afforded a mixture of three products: 3,3,5,6,8‐ pentamethyl‐1,2,3,4‐tetraisoquinolylidene‐1‐acetic acid ether ( 2 ) and its 3,3,5,6,7‐pentamethyl‐( 3 )‐ and 3,3,6,7,8‐pentamethyl‐1,2,3,4‐tetraisoquinolyli‐ dene‐1‐acetic acid ether isomers ( 3 ) in ratio 1:5:1. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:471–476, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20045