由卤代芳硝基物制备卤代芳胺的综述

综述了由卤代芳硝基物还原制备卤代芳胺的三类方法,对三类还原方法的优缺点进行了对比和讨论,重点介绍了第三类制备卤代芳胺的还原方法-催化加氢还原法,最后介绍了催化加氢还原卤代芳香硝基物的新方法及新领域。     

卤代磷脂的合成研究

以大豆磷脂为原料,利用有机卤代试剂制备出一种新型的卤代磷脂。通过正交试验确定了该反应的最佳反应条件：温度７５℃,引发剂量４％,溶剂量１５０ｍｌ,反应时间１．５ｈ。     

卤代烷烃和卤代烯烃在γ—Al2O3催化剂上的反应动力学及吸附

人们已经研究了在γ－Al2O3催化剂上卤代烷烃CH3CF3-nCln和卤代烯烃CH2＝CF2-nCLn系列的多相催化反应，并将其实验结果和计算的热力学数据作了比较。此体系的主反应可由以下反应途径解释：脱卤化氢，加卤化氢，用卤化氢进行的F／Cl交换和cl／F交换。在其他卤代烃反应中观察到的歧化反应在这里并不重要。本文绘出了对主反应的探索，另外，也调查研究了在γ－Al2O3催化剂上CH3CF2Cl的动力学行为以及多种卤代烃的吸附。等量吸附治证明和简单的缩合作用相比卤代烷和固体表面间的相互作用占更为重要的主导地位。     

紫外光下水合电子降解卤代有机物的研究进展

卤代有机物污染问题在世界范围内普遍存在,氧化是一种常见的降解技术,但部分全氯代烃及氟代化合物很难被氧化.水合电子因其极强的还原能力,近年来广泛用于卤代有机物的降解研究,并取得良好的降解和脱卤效果,同时也受到光强、反应介质条件等多种因素的影响,对水合电子的性质、产生方式、卤代有机物降解的影响因素及降解机理进行了介绍,以期...     

气相脱氯化氢制备卤代烯烃的研究进展

含氯卤代烷烃气相脱氯化氢是制备卤代烯烃较为理想的方法,本文总结了近年来气相脱氯化氢的研究进展,其中催化法具有明显的优点。     

卤代芳香族酯的制法及用途

有关卤代邻苯二甲酸酯的制法及其在塑料制品中的性质，曾作过介绍。由于该化合物在聚合物的配方中兼有增塑剂及阻燃剂的多种功能，在电缆及电线绝缘中应用较广，因此，近年来又多有报道。     

5－卤代邻苯二甲酸酐的合成研究

本文介绍了５－卤代邻苯二甲酸酐的合成方法，提出了５－溴代邻苯二甲酸酐的新合成方法。     

多卤代醌和磺酰亚胺的光化反应研究

1,研究了四氯苯醌(TcBQ)与10个α,β-不饱和羰基化合物(E-和Z-苄叉丙酮、E-和Z-肉桂酸乙酯、E-和Z-3-硝基肉桂酸乙酯、E-和Z-查尔酮、E-p-FC_6H_4CH=CHCOC_6H_5,E-3,4-亚甲二氧基查尔酮)以及E-β-溴代苯乙烯的光化环加成反应。用>400nm的光照射TCBQ与上述E-或Z-式烯烃的苯溶液时,以较高产量(72％—     

Double and Triple Differential Cross Sections for Single Ionization of Benzene by Electron Impact

Experimental results for the electron impact ionization of benzene, providing double (DDCS) and triple differential cross sections (TDCS) at the incident energy of 90 eV, measured with a multi-particle momentum spectrometer, are reported in this paper. The most intense ionization channel is assigned to the parent ion (C₆H₆⁺) formation. The DDCS values are presented for three different transferred energies, namely 30, 40 and 50 eV. The present TDCS are given for two fixed values of the ejected electron energy (E₂), at 5 and 10 eV, and an electron scattering angle (θ₁) of 10°. Different features related to the molecular orbitals of benzene from where the electron is extracted are observed. In addition, a semi-empirical formula to be used as the inelastic angular distribution function in electron transport simulations has been derived from the present DDCS result and compared with other expressions available in the literature.     

Recent Advances in Bacteria Identification by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Using Nanomaterials as Affinity Probes

Identifying trace amounts of bacteria rapidly, accurately, selectively, and with high sensitivity is important to ensuring the safety of food and diagnosing infectious bacterial diseases. Microbial diseases constitute the major cause of death in many developing and developed countries of the world. The early detection of pathogenic bacteria is crucial in preventing, treating, and containing the spread of infections, and there is an urgent requirement for sensitive, specific, and accurate diagnostic tests. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is an extremely selective and sensitive analytical tool that can be used to characterize different species of pathogenic bacteria. Various functionalized or unmodified nanomaterials can be used as affinity probes to capture and concentrate microorganisms. Recent developments in bacterial detection using nanomaterials-assisted MALDI-MS approaches are highlighted in this article. A comprehensive table listing MALDI-MS approaches for identifying pathogenic bacteria, categorized by the nanomaterials used, is provided.     

第二过渡周期金属单氧化物电子结构的DFT表征

文章采用九种密度泛函方法系统地研究了第二过渡周期金属单氧化物及其正负离子的键长,频率,电离能,电子亲和势及解离能。     

Fe-P非晶态合金局域结构和电子性质的理论研究

根据Fe-P非晶态合金结构的短程有序、Fe和P之间具较强化学作用和结构中可能存在P-P相互作用的实验事实,选择了单磷原子簇模型FenP(n=1～6,8)和双磷原子簇模型FenP2(n=1～4),用密度泛函理论方法对其进行计算。结果表明,在单磷模型体系中,Fe原子供给P原子电子;而在双磷模型体系中,电子转移方向发生变化,P原子供给Fe原子电子,这与Fe-P非晶态合金的实验结果一致,说明单磷和双磷原子簇模型能较全面反映Fe-P非晶态合金的结构特点。     

As_nP_(4-n)(n=1-3)分子结构和性质的理论研究

为了提供杂原子四面体AsnP4-n(n=1-3)的更多的结构和性质方面的信息,利用B3LYP/6-311++G**理论研究了P4,AsP3,As2P2,As3P和As4分子在气相的几何体结构并进行了解析振动频率的分析。采用Dmol3程序在GGA,BLYP/DNP和LDA,PWC/DNP理论水平上研究了五个分子的能量和电离势,通过分析能量得出了五个分子的稳定性是依次减弱;通过比较电离势的大小得出五个分子失电子的能力依次增强。基于统计热力学,求得温度298.15~1000.00K范围五个分子的熵、热熔,焓及吉布斯自由能的大小。     

电离放电化学的研究趋势

概述了电离放电化学研究现状与发展趋势，认为今后的发展方向是应用特种新工艺实施高气压强电离放电方法，激励气体分子分解、电离成离子、原子、激发态原子(及分子)和自由基等，按预定模型合成新物质、新分子，使常规难以进行的化学反应得以进行或加速进行。并举例说明了强电离放电化学在化学工业、环境工程和材料工业等方面将具有极其广阔的应用前景。     

氨苄西林质谱解析及其离子化方式研究

通过对于氨苄西林正离子模式质谱谱图的解析,探讨了氨苄西林的离子化方式和裂解规律。研究表明：氨苄西林存在3种质子化方式,不同的质子化方式所形成分子离子具有不同的裂解方式;质子化的质子具有明显的活性,是质谱进一步裂解的主要原因;离子化方式对于质谱峰的丰度会产生重要影响。本研究为氨苄西林质谱分析和构效关系研究提供了重要的实验基础与理论依据。     

Electron emission suppression from hydrogen-terminated n-type diamond

By total photoelectron yield spectroscopy (TPYS), we have found a thermal instability of a negative electron affinity in hydrogen-terminated n-type diamond films, which has never been observed for intrinsic and p-type diamond films. Experimentally, we have succeeded in detecting surface defect states and surface valence band extended states on the same n-type sample after soft annealing from 100 to 300 °C, which allowed us to evaluate the surface Fermi level and surface band bending using phosphorus doping parameters. Our results show that “quasi-positive” electron affinity prevents electron emission from an n-type diamond film even though its surface has a negative electron affinity.     

Electron Attachment Studies with the Potential Radiosensitizer 2-Nitrofuran

Nitrofurans belong to the class of drugs typically used as antibiotics or antimicrobials. The defining structural component is a furan ring with a nitro group attached. In the present investigation, electron attachment to 2-nitrofuran (C₄H₃NO₃), which is considered as a potential radiosensitizer candidate for application in radiotherapy, has been studied in a crossed electron–molecular beams experiment. The present results indicate that low-energy electrons with kinetic energies of about 0–12 eV effectively decompose the molecule. In total, twelve fragment anions were detected within the detection limit of the apparatus, as well as the parent anion of 2-nitrofuran. One major resonance region of ≈0–5 eV is observed in which the most abundant anions NO₂⁻, C₄H₃O⁻, and C₄H₃NO₃⁻ are detected. The experimental results are supported by ab initio calculations of electronic states in the resulting anion, thermochemical thresholds, connectivity between electronic states of the anion, and reactivity analysis in the hot ground state.     

锌离子螯合亲和层析分离纯化谷胱甘肽的研究

以谷胱甘肽的酵母抽提液为原料,用自制的以壳聚糖小球为载体、Zn2 为配基的金属螯合亲和层析柱分离纯化谷胱甘肽(GSH).用含0.5 mol·L-1NH4Cl的pH值4.2、0.02 mol·L-1的磷酸盐缓冲溶液洗脱,然后经浓缩、冷冻干燥处理,即得到分离纯化的GSH.结果表明,上柱谷胱甘肽抽提液浓度为 132.30 mg·(100 mL)-1、上柱pH值为7.0时,谷胱甘肽回收率为68.61%;洗脱液中氯化铵浓度为0.5 mol·L-1、洗脱pH值为6.0时,谷胱甘肽洗脱回收率达到44.47%.