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UV-radiation Dose Assessment for LR-115 Track Detector by Using UV-visible and ftir spectroscopy Techniques

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Journal of Physical Science and Application 2016年第1期6卷 88-91页

作者： Hussain A. AI-Jobouri Fala Hatcm Taha Department of Physics AL-Nahrain University Baghdad Iraq

Abstract： In the present work, studies the effect uv-radiation dose （5 J/cm2 to 360 J/cm2 ） with power 15 W to LR-115 track detector thickness 100 μm. Absorbance-A was measured at wavelength 600 nm and 650 nm by usinguv-visible spectroscopy and measure the transmission percent -- T% and deviation at the wavenumber-w2907 cm1 by using Fourier infrared -- ftir spectroscopy. The relationship between the dose of radiation to the uv-radiation （J/cm2） and the absorbance-A at wavelength 600 nm and 650 nm and the wavenumber-w 2907 cm-1 was calculate as a polynomial relation .The present study show that there is a possibility to use the detector LR- 115 to assessment doses of exposure to uv-radiation in the medical and environmental fields.

关键词： LR-115 track detector uv-irradiation UV-visible spectroscopy ftir spectroscopy SSNTDs.

ftir STUDIES ON THE MODEL POLYURETHANE HARD SEGMENTS BASED ON A NEW WATERBORNE CHAIN EXTENDER DIMETHYLOL BUTANOIC ACID (DMBA)

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Chinese Journal of Polymer Science 2004年第3期22卷 225-230页

作者：马德柱 Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026 China

Three model polyurethane hard segments based on dimethylol butanoic acid (DMBA) and 1,6-hexane diisocyanate (HDI), toluene diisocyanate (TDI) and 4,4'-diphenylmethane diisocyanate (MDI) were prepared by the solution method. Fourier Infrared (ftir) spectroscopy was employed to study the H-bonds in these model polyurethanes. The model polyurethane hard segment prepared from HDI and 1,4-butanodiol (BDO) was used for comparison. It was found that the incorporation of the pendent carboxyl through DMBA into the model hard segments weakens the original NH…O = C H-bond but gives more H-bond patterns based on the two H-bond donors, urethane NH and carboxylic OH. The carboxylic dimer is one of the main H-bond types and is stronger than another main H-bond type NH…O=C. In addition, the H-bond in aromatic model hard segments is stronger than that of aliphatic hard segments. The appearance of the free C=O and the fact that almost all N—H is H-bonded suggest that there possibly exist either the third H-bond acceptor or the H-bond formed by one acceptor with two donors.

关键词： Model hard segment H-bond Polyurethane with carboxyl ftir spectroscopy

Synthesis,structure and spectroscopic studies of europium complex with S(+)-mandelic acid

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Journal of Rare Earths 2011年第12期29卷 1188-1191页

作者： M.Babij A.Mondry Faculty of Chemistry University of Wrocaw

The Eu^3＋ complexes with S（＋）-mandelic acid were synthesized in the form of powders by mixing aqueous solutions of EuCl3, S（＋）-mandelic acid and NaOH in different molar ratios. The powders were characterized by elemental analysis, X-ray powder diffraction （XRPD.） method, Fourier transform infrared （ftir） and Raman spectroscopy, UV-vis reflectance and luminescence spectra as well as luminescence lifetime measurements. It was found that all studied powders of Eu^3＋ complexes with S（＋）-mandelic acid were isostructural and crystalline and formed compounds with the formula Eu（Man）3（H2O）2.

关键词： europium mandelic acid emission ftir spectroscopy Raman sDectroscopy rare earths

IR STUDY ON MONOMOLECULAR PARTICLE AGGLOMERATES OF POLYSTYRENE OBTAINED BY FREEZE-DRYING OF ITS DILUTE SOLUTION

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Chinese Journal of Polymer Science 2002年第4期20卷 381-383页

作者： Song Wang Qing-hua Wang Rong-shi Cheng Research Center of Materials Beijing Institute of Technology Beijing 100081, China Department of Chemistry Nanjing University Nanjing 210093, China Research Center of Materials Beijing Institute of Technology 北京 100081 Department of Chemistry Nanjing University Nanjing 210093

The monomolecular particle agglomerates of polystyrenes were obtained by freeze-drying of its very dilute solutions of 1.3 x 10(-5)-2.0 x 10(-5) g/mL in benzene:cylcohexane (100:1) solvents, and they were annealed at room temperature for hundred days before use. According to C-13-NMR measurement the polystyrenes should be practically atactic. The number average molecular weights of the samples are 2.80 x 10(3), 2.00 x 10(4), and 1.55 x 10(6), respectively. The freeze-dried aPS with a molecular weight higher than 10(4) show two new IR absorption bands at 1098 and 1261 cm(-1), which are absent in the normal aPS and freeze-dried styrene oligomer. It was also found that the low molecular weight samples can only form powders, whereas the freeze-dried aPS with higher molecular weight form a mixture of powders and fibrils, of which the longer fibrils show a much stronger 1261 cm(-1) band than the shorter fibrils and the powder. It seems that the 1261 cm(-1) band corresponds to the stacking behavior of monomolecular particles.

关键词： monomolecular particles atactic polystyrene ftir spectroscopy

Adsorption and Desorption of Mercury(Ⅱ) in Three Forest Soils in Shandong Province,China

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Pedosphere 2013年第2期23卷 265-272页

作者： XUE Tong WANG Ren-Qing ZHANG Meng-Meng DAI Jiu-Lan Environment Research Institute Shandong University Institute of Ecology and Biodiversity School of Life SciencesShandong University Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology Shandong University

As one of the most toxic heavy metals with persistence, bioaccumulation, and toxicity in environment, mercury and its envi- ronmental problems have caused a global concern. To fully understand the behavior and fate of mercury （Hg）（II） in forest soils, a series of batch experiments were conducted to determine the adsorption and desorption characteristics of Hg（II） by three dark brown forest soils from Mount Taishan, Laoshan Mountain, and Fanggan Village in Shandong Province, China. The adsorption solution was prepared using 0.1 mol L-1 NaNO3 as background electrolyte, with Hg（II） at rising concentration gradients of 0.0, 2.0, 4.0, 6.0, 8.0, and 10.0 mg L-1. Fourier transform infrared （ftir） spectroscopy was adopted to characterize the soil samples and soil-Hg complexes. It was found that Hg（II） adsorption isotherms could be well fitted with both Langmuir and Freundlich equations. The soil from Mount Taishan had the largest potential Hg（II） adsorption capacity, though with less adsorptive intensity. The percentages of Hg（II） desorbed from all soil samples were less than 0.6~, which suggested that all the soils studied had a high binding strength for Hg（II）. The soil from Mount Taishan had a higher Hg（II） desorption capacity than the other soils, which indicated that the Hg（II） deposited on the topsoil of Mount Taishan from atmosphere may easily discharge to surface water through runoff. Results of the ftir spectroscopy showed that the three soils contained the same functional groups. The relative absorbencies of soil-Hg complexes changed significantly compared with those of the soil samples and the adsorption of Hg（II） mainly acted on the O-H, C-O, and C=O groups of the soils.

关键词： atmosphere deposition binding strength ftir spectroscopy functional groups soil^Hg complex

Corrosion study of resorbable Ca60Mg15Zn25 bulk metallic glasses in physiological fluids

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Progress in Natural Science:Materials International 2017年第5期27卷 627-634页

作者： Rafa? Babilas Anna Bajorek Adrian Radoń Ryszard Nowosielski Institute of Engineering Materials and Biomaterials Silesian University of Technology A.Chelkowski Institute of Physics University of Silesia

The corrosion activity of amorphous plates of Ca60Mg15Zn25alloy was *** biocompatible elements were selected for the alloy *** electrochemical corrosion and immersion tests were carried out in a multi-electrolyte fluid and Ringer's *** corrosion behavior was observed for the samples tested in a multi-electrolyte fluid despite the active dissolution of Ca and Mg in Ringer's *** experimental results indicated that reducing concentration of NaCl from 8.6 g/dm3for Ringer's solution to 5.75 g/dm3caused the decrease of the corrosion *** volume of the hydrogen evolved after 480 min in Ringer's solution（40.1 ml/cm2）was higher in comparison with that obtained in a multi-electrolyte fluid（24.4 ml/cm2）.The values of opencircuit potential(EOCP)for the Ca60Mg15Zn25glass after 1 h incubation in Ringer's solution and a multielectrolyte fluid were determined to be-1553 and-1536 m V vs.a saturated calomel electrode（SCE）.The electrochemical measurements indicated a shift of the corrosion current density(jcorr)from 1062μA/cm2for the sample tested in Ringer's solution to 788μA/cm2for the specimen immersed in a multi-electrolyte *** corrosion products analysis was conducted by using the X-ray photoelectron spectroscopy（XPS）.The corrosion products were identified to be CaCO3,Mg（OH）2,CaO,MgO and Zn *** mechanism of corrosion process was proposed and described based on the microscopic *** X-ray diffraction and Fourier transform infrared spectroscopy（ftir）also indicated that Ca（OH）2,CaCO3,Zn（OH）2and Ca(Zn（OH）3)2·2H2O mainly formed on the surface of the studied alloy.

关键词： Ca-based metallic glasses X-ray photoelectron spectroscopy ftir spectroscopy X-ray diffraction Corrosion resistance Hydrogen evaluation

Chemical Investigation of the NO_x Detection Mechanisms by Semiconductor Metal Oxide Nanoparticles

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稀有金属材料与工程 2006年第A3期35卷 40-42页

作者： Marie-Isabelle Baraton Lhadi Merhari SPCTS-UMR CNRS 6638 Faculty of SciencesF-87060 LimogesFrance CERAMEC R&D F-87000 LimogesFrance

This work reports an ftir study of the NO_x adsorption/desorption cycles on tin oxide nanosized particles under the operating conditions of real sensors (150℃,in presence of O_2).The chemical reactions are monitored in situ and correlated with the variations of the SnO_2 electrical *** the basis of the ftir spectra,two contributing mechanisms for the NO_x detection are *** first one presents the formation of bridged nitrate groups bound to the SnO_2 surface via oxygen vacancies acting as electron donor *** second mechanism also involves surface oxygen vacancies in the coordination of NO_x,but this time the formation of NO_x anionic species is *** mechanisms lead to the decrease of the electrical conductivity under NO_x ***,the bridged nitrate groups are not reversible under gas desorption and thus irreversibly contaminate the surface after the first NO_x *** the contrary,the nitrosyl anionic species are reversible and,from the second NO_x adsorption/desorption cycle,ensure the reproducibility of the sensor response.

关键词： NO_x detection surface reactions ftir spectroscopy Tin oxide SnO2 nanoparticles chemical sensors

A V-shaped spectroscopic cell for ftir measurements

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Chinese Chemical Letters 2011年第4期22卷 481-484页

作者： Xiang Qin Lin Zhi Xiang Zhang Wan Qun Hu Department of Chemistry University of Science and Technology of China Hefei 230026 China

A V-shaped spacroscopic cell（V-cell） was constructed using two CaF2 optical plates for ftir light transparent measurements in the range of 4000-1000 cm^（-1）.The spectrum of ethanol was characterized with the standard spectra,excellent fitting was achieved with a bottom-width correction *** principle of the V-cell was discussed,giving equations for the data *** shows that the V-cell is an auto-focus type spectroscopic cell,which can effectively avoid absorption saturation with amplifications for weak absorption *** V-cell design is simple and effective,easy to operate,suitable for applications in liquid samples with high absorption bands,willing to have broad application prospects.

关键词： V-shaped cell ftir spectroscopy Light transparent Error correction Demountable Ethanol

Solvent effects on hydrogen bonding between primary alcohols and esters

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1928-1931页

作者： DHARMALINGAM K. RAMACHANDRAN K. SIVAGURUNATHAN P. Department of Physics Annamalai University Annamalai Nagar 608002 Tamilnadu India

The interaction by hydrogen bond formation of some primary alcohols （ l-heptanol, l-octanol and l-decanol） with esters （methyl methacrylate, ethyl methacrylate and butyl methacrylate） was investigated in non-polar solvents viz., n-heptane, CC14 and benzene by means of ftir spectroscopy. Formation constants and free energy changes of complex formation were determined. The dependence of the equilibrium constants and free energy changes of complex formation on the alkyl chain length of both the alcohols and esters are discussed. The solvent interaction between the solute and solvent. effect on the hydrogen bond formation is discussed in terms of specific

关键词： ftir spectroscopy Primary alcohols Esters Hydrogen bonding Solvent effect