实验室智能化管理的探讨

结合智能化一卡通网络管理系统在山东省计量科学研究院实验室管理中的应用情况,研讨实验室智能化管理的相关问题,重点介绍系统结构、系统特点、系统功能和系统应用。     

基础电化学实验的计算机测控系统

设计了一个由样品系统、电化学测试系统及计算机组成的可用于基础电化学实验测量的计算机测控系统。两个学期的学生实验表明该系统比传统的基础电化学实验测量系统的精度大大提高 ,能提供更多的信息且缩短了实验时间。这一系统还可用于多种电化学测量 ,效果良好。     

基于多肽的药物递送系统研究进展

药物递送系统是将药物输送到药物作用靶点的系统,理想的递送系统可以提高药物作用效果并降低给药剂量和毒副作用.本文综述了药物递送系统中的多肽类药物递送系统的研究进展.多肽具有易合成、易代谢、免疫原性低、毒副作用低等优点,多肽支链上大量的官能团可以和药物偶联,是药物递送系统的重要发展方向.本文从靶向肽、穿透肽、响应肽和组装肽四个方面介绍了多肽药物递送系统的原理和实例.组装肽可以形成纳米结构,显著提升多肽药物递送系统的稳定性,可以实现长效释放.组装肽体内原位调控进一步增加了多肽药物递送系统的智能型、精准性,展现出巨大的转化潜力.     

蝇视觉系统的图形-背景分辨的计算机模拟

蝇视觉系统的图形-背景分辨及模式分辨是计算机视觉研究中的重要问题之一。本文在Reichardt等的蝇视系统的图形-背景分辨的计算神经网络模型的基础上,对蝇视觉系统在非平稳条件下的图形-背景分辨进行了系统的计算机模拟。结果表明,模型与模拟对于行为实验结果具有预测能力。本文提出假设:人视系统的运动感知及初级模式分辨也可能是以运动检测器为输入端的图形-背景系统来实现的。     

测定晶体结构的系统试差法的研究(Ⅲ)──SYSTEM 90程序系统和应用

介绍了最近研究的系统试差法的基本公式和它的程序系统SYSTEM90的构成．应用该程序系统对收集到的5个难解结构进行了成功的测定．实验结果显示了SYSTEM90程序系统的威力．最后在分析的基础上，提出了系统试差法程序系统不同于其它直接法的四个特点．     

反渗透系统的经济运行与维护

广东中山发电A厂两套设计出力50T/h的反渗透系统(RO)自1997年12月投产以来已运行6年多时间,其间进行了多次清洗,清洗后系统投入运行所测数据达到系统正常运行标准,其清洗后的出力达到50T/h左右。根据国内外理论介绍,反渗透系统中反渗透膜随运行时间增加,系统产水量年递减10%,显然该厂的反渗透系统在经济运行方面取得了很好的成绩。     

子的配分函数——物理意义与作用

讨论怎样理解子的配分函数的物理意义,以及它和系统的配分函数在计算热力学函数中的作用,指出它既不是系统的广延性质,也不是系统的强度性质,只是联系系统热力学函数与微观信息的纽带。     

破片钢光谱标准样品的制备

研制了一种用于制备破片钢光谱标准物质的多孔浇注系统。介绍了该多孔浇铸系统的结构以及利用该系统制备光谱标准样品的过程。利用该系统制备的破片钢光谱标准样品均匀性良好,同时,该系统具有很好的灵活性,可以制备不同尺寸、不同质量的各种破片钢光谱标准样品。     

测定晶体结构的系统试差法的研究(III) SYSTEM 90程序系统和应用

介绍最近研究的系统试差法的基本公式和它的程序系统ＳＹＳＴＥＭ９０的构成，应用该程序系统对收集到的５个难解结构进行了成功的测定，实验结果显示了ＳＹＳＴＥＭ９０程序系统的威力，最后在分析的基础上，提出了系统试差法程序系统不同于其它直接法的四个特点。     

单向耦合Hindmarsh-Rose系统的同步

采用数值模拟方法, 研究了由两个具有不同初始条件单向耦合的Hindmarsh-Rose神经元所组成系统的动力学行为. 研究结果表明, 耦合强度对两个神经元的同步具有重要的影响. 当两个神经元的控制参数取值不同时, 即在驱动系统和响应系统均处于混沌态及驱动系统处于周期振荡态, 响应系统处于混沌态两种情况下, 随耦合强度的增加其放电活动都能从不同步达到相位同步, 最后实现近似完全同步.     

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.     

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.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

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.