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81.
The detection of TNT and related nitroaromatic compounds in seawater is of great interest. Electrochemical techniques can be applied for detection purposes since nitroaromatic compounds contain easily reducible nitro groups. In this study, we investigate the performance of thermally reduced graphenes prepared by three different oxidative methods: Hummers, Staudenmaier and Hofmann methods with consequent thermal exfoliation. The Hofmann method‐based graphene was found to exhibit the highest sensitivity in detecting TNT electrochemically. Extended study on the detection of TNT in seawater using the graphene material provided significant improvements in the detection sensitivity. These findings will have profound impacts on the detection of nitroaromatic explosives in seawater. 相似文献
82.
Influence Factors on Particle Growth for On-line Aerosol Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry 下载免费PDF全文
An evaporation/condensation flow cell was developed and interfaced with the matrix-assistedlaser desorption/ionization (MALDI) time-of-flight mass spectrometer for on-line bioaerosoldetection and characterization, which allows matrix addition by condensation onto the laboratory-generated bioaerosol particles. The final coated particle exiting from the con-denser is then introduced into the aerodynamic particle sizer spectrometer or home-built aerosol laser time-of-flight mass spectrometer, and its aerodynamic size directly effects on the matrix-to-analyte molar ratio, which is very important for MALDI technique. In order to observe the protonated analyte molecular ion, and then determine the classification of bi-ological aerosols, the matrix-to-analyte molar ratio must be appropriate. Four experimental parameters, including the temperature of the heated reservoir, the initial particle size, its number concentration, and the matrix material, were tested experimentally to analyze their influences on the final particle size. This technique represents an on-line system of detec-tion that has the potential to provide rapid and reliable identification of airborne biological aerosols. 相似文献
83.
电感耦合等离子体原子发射光谱法同时测定槲寄生中的微量元素 总被引:1,自引:0,他引:1
采用硝酸-双氧水对槲寄生全药及煎煮液进行湿法消解,用电感耦合等离子体原子发射光谱法(ICP-AES)同时测定试样中Cu,Mg,Zn,Mn,Ni,Se,K,Na,Ca和Fe等元素的含量。该法的的加标回收率为91.6%~108.9%,变异系数为0.47%~4.59%,具有良好的准确度和精密度。结果表明:槲寄生中含有丰富的K和Ca元素,Na和Mg的含量也相对丰富,为进一步研究槲寄生的药理提供了科学的数据。 相似文献
84.
The aim of this study is to efficiently utilize catalytic properties of silver nanoparticles and nitrogen doped graphene and their combined synergistic effect. For this purpose, nitrogen doped reduced graphene oxide-silver (NrGO-Ag) nanocomposites were synthesized by a facile, environmentally friendly, one-pot hydrothermal method for the first time and characterized by UV–Vis, FTIR, XRD, XPS, SEM, and TEM. Catalytic activity of the synthesized nanocomposites was tested against 4-nitrophenol (4-NP) and methylene blue (MB) reduction reactions in the presence of NaBH4. Total degradation was achieved in both reactions in 210 and 44 s, and pseudo first order reaction rate constants were calculated as 0.0071 and 0.0322 s−1 for 4-NP and MB reduction reactions, respectively. 相似文献
85.
Jerald S. Bradshaw Ljubo Golič Miha Tišler 《Monatshefte für Chemie / Chemical Monthly》1988,119(3):327-332
Oxidative dimerizations of some naphthalene derivatives were studied. With vanadium oxytrichloride either a new C-C bond formation occured or the reagent caused chlorination of the ring. Attempts to induce photochemically a new C-C bond failed.
Versuche zur Herstellung einiger Binaphthalin-Derivate
Zusammenfassung Die oxidative Dimerisierung einiger Naphthalinderivate wurde untersucht. Mit Vanadiumoxytrichlorid wird eine neue C-C-Bindung gebildet, es wurde jedoch auch Chlorierung des Naphthalinringes beobachtet. Versuche zur photochemischen Bildung einer C-C-Bindung scheiterten.相似文献
86.
A. Ti B. L. Ling Q. S. Fei X. Gao 《International Journal of Infrared and Millimeter Waves》2007,28(3):243-249
The incoherent radiation emanating out of the tokamak plasmas gives vital information about the electron temperature. Electron
cyclotron emission (ECE) is a powerful diagnostic tool for the measurement of electron temperature due to many advantages
such as the high spatial and temporal resolutions. This paper presents the sixteen channel superheterodyne radiometer as an
electron cyclotron emission diagnostic to measure the electron temperature on HT-7 tokamak. 相似文献
87.
88.
Chao Zhao Peisi Xie Ti Yang Hailin Wang Arthur Chi Kong Chung Zongwei Cai 《中国化学快报》2018,29(8):1281-1283
Exposure to BPS induced glycerophospholipid fatty acid remodeling, which might be useful in toxicity evaluation for bisphenols-induced hepatic diseases. 相似文献
89.
Zhi Hui Zhang Xian He Bu Zhi Ang Zhu Zong Hui Jiang Yun Ti Chen 《Transition Metal Chemistry》1996,21(3):235-237
Summary A new binuclear NiII complex, [{(TPA)Ni(-Cl)}2]-(ClO4)2·H2O (1), where TPA = tris(2-pyridyl-methyl) amine, has been prepared and characterized. The X-ray crystal structure and variable temperature magnetic susceptibility (4–300 K) of the complex have been determined. The two NiII atoms of (1) are in a distorted octahedral environment and are bridged by Cl atoms. Ni-Cl distances are 2.363(6) and 2.503(7) Å, and the Ni-Cl-Ni angle is 92.7(2)°. The metal atoms are separated by a non-bonding distance of 3.523 Å.The effective magnetic moment of (1) increases slightly with decreasing temperature and appears to reach a maximum before decreasing. The observed data were fitted to the Heisenberg model and the results indicate that there is a ferromagnetic interaction (positive J) and weak antiferromagnetic intermolecular interaction (negative ). 相似文献
90.
Mario Merslavič Branko Stanovnik Miha Tišler 《Monatshefte für Chemie / Chemical Monthly》1985,116(12):1447-1458
New syntheses of oxazolo[4,5—d]pyridazine derivatives7 and11 were achieved by the cyclization of substituted N-pyridazin-5-ylformamide oximes6 and10. Under mild reaction conditions the transformations of the substituted amino group at position 2 of the oxazolo[4,5—d]pyridazine system7 occured to produce the compounds11, 14, and15, while under more drastic reaction conditions the nucleophilic attack at carbon at position 2 followed by the ring opening of the oxazole part of the molecule was observed to give the compounds13, 16, 17 and18.
Transformationen von N-Heteroarylformamidinen und N-Heteroarylformamidinoximen. Neue Synthesen und Transformationen von Oxazolo[4,5—d]pyridazinen
Zusammenfassung Mittels Cyclisierung substituierter N-Pyridazin-5-ylformamidoxime6 und10 wurden neue Synthesemöglichkeiten von Oxazolo[4,5—d]pyridazinderivaten erschlossen. Bei milden Reaktionsbedingungen trat Transformation der substituierten Aminogruppe an Position 2 des Oxazolo[4,5—d]pyridazin-Systems unter Bildung der Verbindungen11, 14 und15 ein, währenddessen unter drastischeren Reaktionsbedingungen ein nucleophiler Angriff am Kohlenstoff-2, gefolgt von einer Ringöffnung unter Bildung der Verbindungen13, 16, 17 und18 eintrat.相似文献