磷小姐升职记

将磷元素拟人化,通过生动的语言,讲述了她在生命体内的作用以及在人类生活中的应用,让磷元素的生理功能以及应用更简单易懂,使读者体会到磷元素独特的美。     

食品中磷的检测方法

磷是人体内的重要元素之一,对人体生命活动有十分重要的作用,如何快速、简便、准确、灵敏地检测食品中磷的含量已经引起了世界各国的重视.本文总结了前人的研究工作,概述了近年来食品中总磷及有机磷农药的检测研究进展,分析了各种检测方法的优势和局限性,展望了未来该领域研究的发展趋势.     

内、外环境元素平衡是协调人与自然关系解决元素与健康问题的一个重要环节

从协调人和自然关系及人民体质建设的宏观角度，探讨了环境元素与生命健康关系及其规律的方法论和解决问题的途径。明确元素存在的普遍性、内外环境元素的相关性，提出了生命元素周期变化节律及内、外环境元素整体动态的相对平衡和纵横向相对稳定的比例关系是保证生命健康的基础等概念。强调系统研究元素生物效应的重要性和人类活动在扩大元素三维分布不均匀性和增加元素与健康问题复杂性中的作用，由此提出了通过生物地球化学食物链系统研究和解决环境元素与生命健康关系问题是协调人与自然关系进行人民体质建设的重要途径。     

蛋白质磷酸化作用的电化学检测方法

蛋白质的磷酸化作用是一种可逆的翻译后修饰方式,几乎参与生物体内所有关键生命活动,在核内基因的特定表达、细胞的分裂分化以及各种生命活动的转导中发挥重要意义。基于磷酸化前后电化学信号的改变,利用电化学传感器的方法能快速简便地检测蛋白质的磷酸化作用,且具有较高的选择性和灵敏度。本文回顾了几种常用的电化学检测磷酸化作用的方法,基于电极材料的不同进行了分类与总结,汇总了每种方法中用到的修饰电极的纳米材料及生物分子,最后总结了电化学方法检测蛋白质磷酸化的优缺点,并对有效检测磷酸化作用进行了前景展望。     

开展环境、食物、人体全元素研究的重要意义

人类是地球上的生命在亿万年进化过程中的最高级产物，与地球环境变化密切相关。地球上有92种天然元素，在人体内已经找到了81种，它们构成人体的所有组织和器官。虽然有70余种元素合起来仅占人体质量的0．05％，而被称为微量元素，它们同样在生命活动中有着不可替代的作用，其在体内的变化也影响着人体生命活动的正常进行。人体必需生命元素的数量是在随着分析技术的进展及人们对元素研究的逐步深入而不断扩展的。     

金属离子在生命过程中的作用机制

生命活动是一系列错综复杂的生物反应,包含着元素的获取、作用、代谢等生理过程。文章重点从机体组织构成、生长发育、能量和物质的新陈代谢、生物和神经信号的传递等不同生命活动中金属离子所起的作用及其作用机制进行了综述。结果表明金属离子在许多生命活动中起到了至关重要的作用。文章为生物元素调节、金属药物研制和疾病防治等应用提供了一定的理论基础。     

自然界中元素的分布和门捷列夫周期系

由地壳内元素分布的详细研究,发现它们的发生并不是偶然的,而是遵循着一定的规律的。利用这些规律,我们就可以在“科学的基础”上来研究地球上的矿藏,并且在很大的程度上,使我们费很小的力量即可以发现并研究有用矿物的新矿源。很早以前认为有许多元素在动物和植物的生命上具有首要的重大意义,如:碳、氧、氢、氮、硫、磷、氯、硅、钾、钙、镁和铁,而其他的元素则几乎不具有任何意义。但是按生物体中稀有的元素分布的新材料证明:这些元素在动物和植物的生命中     

电感耦合等离子体原子发射光谱法测定锰硅合金中磷

锰硅合金是由锰、硅、铁及少量碳和其它元素组成的合金,是一种用途较广、产量较大的铁合金。产品呈块状,颜色为灰褐色,主要元素为锰、硅、铁、碳、磷、硫,其中锰、硅、铁为有用元素,碳、磷、硫为有害元素。锰硅合金是炼钢常用的复合脱氧剂,又是生产中低碳锰铁和电硅热法生产金属锰的还原剂。锰     

痕量元素磷的有机相比色测定

黄磷污水中之元素磷对生物有极大的毒害,为此,控制排放污水中元素磷含量,避免周围环境的污染十分重要。我们对污水中痕量元素磷的测定方法进行了试验。电炉制磷污水中元素磷含量极低,经处理后的排放污水仅含0.05毫克/升以下。但污水组成极为复杂,干扰元素磷测定的物质又多,水溶性磷含量为元素磷之近千倍,因此要获得正确的分析结果,必需:1.将元素磷和水溶性磷分离。2.分离后的元素磷氧化成正磷酸。3.用灵敏度较高的测定方法进行测定。我们采用苯为溶剂萃取元素磷,使和     

KED碰撞模式-电感耦合等离子体质谱（ICP-MS）法测定多种煤中磷

煤是重要的工业生产和生活能源燃料,磷元素又是煤中主要的有害微量元素之一,磷元素极易进入大气、水体和土壤,对环境和生态造成严重污染,为快速准确测定不同煤质样品中磷元素的含量,建立了混合酸消解-KED碰撞模式-电感耦合等离子体质谱法（ICP-MS）测定多种煤中磷的方法。讨论了样品灰化温度、灰化时间、消解试剂等对磷元素测定结果的影响,试样经箱式电阻炉在815 ℃,灼烧1.5 h灰化后,采用盐酸-硝酸-氢氟酸-高氯酸体系进行酸解,王水提取,以磷元素特定质量数31 (质荷比,m/z )定性,以磷元素和103Rh内标元素质谱信号的强度比值与磷元素的浓度成正比进行定量分析,向碰撞反应池中通入碰撞混合气,与相同质量数的多原子离子物质的发生有效碰撞使其质荷比发生变化,从而降低氧化物产率、消除双电荷产生的质谱干扰,准确测定试样中磷的含量。磷标准溶液浓度在0.5～50 μg/mL范围内呈现良好的线性关系,磷校准曲线方程为y=3985x-226.23,相关系数(R2) =0.9998。方法检出限为0.96 μg/g。选用17种不同种类国家一级标准物质进行验证,测定值与认定基本一致,相对标准偏差(RSD)均≤9.6%,(n=12),相对误差(RE) 均≤4.6%,各种标准物质磷元素测定t值均小于2.20（t 0.05,11值）,该方法测定结果与标准物质认定值具有较好的一致性,且无显著性差异,该方法可用于不同煤质样品中磷元素的测定。     

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.     

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.     

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.     

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.