检索结果-南通市图书馆

Plasma Science and Technology 2021年第9期23卷 123-134页

作者： Jianping LIANG Xiongfeng ZHOU Zilu ZHAO Hao YUAN Hongli WANG Wenchun WANG Dezheng YANG Key Lab of Materials Modification(Dalian University of Technology) Ministry of EducationDalian 116024People's Republic of China

In this paper,unipolar pulse(including positive pulse and negative pulse)and bipolar pulse voltage are employed to generate diffuse gas–liquid discharge in atmospheric N2with a rumpetshaped quartz *** current–voltage waveforms,optical emission spectra of excited state active species,ftir spectra of exhaust gas components,plasma gas temperature,and aqueous H2O2,NO2-,andNO3-production are compared in three pulse modes,meanwhile,the effects of pulse peak voltage and gas flow rate on the production of reactive species are *** results show that two obvious discharges occur in each voltage pulse in unipolar pulse driven discharge,differently,in bipolar pulse driven discharge,only one main discharge appears in a single voltage pulse *** intensities of active species(OH(A),and O(3p))in all three pulsed discharge increase with the rise of pulse peak voltage and have the highest value at 200 ml min-1of gas flow *** absorbance intensities of NO2and N2O increase with the increase of pulse peak voltage and decrease with the increase of gas flow *** the same discharge conditions,the bipolar pulse driven discharge shows lower breakdown voltage,and higher intensities of excited species(N2(C),OH(A),and O(3p)),nitrogen oxides(NO2,NO,and N2O),and higher production of aqueous H2O2,NO2-,andNO3-compared with both unipolar positive and negative discharges.

关键词： nanosecond pulse discharge gas-liquid discharge optical emission spectra reactive species ftir spectra

SYNTHESIS OF POLYCATECHOL WITH ELECTROCHEMICAL ACTIVITY AND ITS PROPERTIES

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2002年第6期20卷 517-524页

作者： Yong Kong Shao-lin Mu Bing-wei Mao Department of Chemistry School of Sciences, Yangzhou University Yangzhou 225002, China State Key Laboratory of Physical Chemistry of the Solid Surface, Xiamen University,Xiamen 361005, China Yangzhou Univ Sch Sci Dept Chem Yangzhou 225002 Peoples R China Xiamen Univ State Key Lab Phys Chem Solid Surface Xiamen 361005 Peoples R China

The electrochemical polymerization of catechol on platinum has been carried out using repeated potential cycling between -0.2 and 1.1 V (versus SCE). The electrolytic solution consisted of 0.2 mol dm(-3) catechol, 0.5 mol dm(-3) NaCl and 0.1 mol dm(-3) Na2HPO4 with pH 8.72. Catechol can not be polymerized at pH greater than or equal to 10.12. Polycatechol has an electrochemical lactivity at pH less than or equal to 4. The anodic and cathodic peak potentials of polycatechol shift towards more negative values as the pH of the solution increases from 1 to 4. The electrochemical activity of polycatechol hardly changes in this pH region, but it decreases slowly with time. This is caused by oxygen in air, which leads to an irreversible oxidation of polycatechol. This property is favorable for protecting metals from corrosion. Raman and ftir spectra of polycatechol and catechol are quite different. AFM images of polycatechol films provide evidence that the image of the oxidized state of polycatechol is markedly different from that of the reduced one. This difference is caused by doping and dedoping of polycatechol.

关键词： catechol polycatechol electrochemical activity Raman spectra ftir spectra AFM images

Removal of trivalent samarium from aqueous solutions by activated biochar derived from cactus fibres

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2016年第1期34卷 99-104页

作者： Loukia Hadjittofi Styliana Charalambous Ioannis Pashalidis Department of Chemistry University of Cyprus

The efficiency of activated biochar fibres obtained from Opuntia Ficus lndica regarding me sorpuon oi trlvalent samarium （Sm（Ⅲ）） from aqueous solutions was investigated by batch experiments. The effect of various physicochemical parameters （e.g. pH, initial metal concentration, ionic strength, temperature and contact time） on the Sm（III） adsorption was studied and the surface species were characterized by ftir spectroscopy prior to and after the lanthanide sorption. The experimental results showed that the acti- vated biochar fibres possessed extraordinary sorption capacity for Sm（Ⅲ） in acidic solutions （qmax=90 g/kg, pH 3.0） and near neutral solutions （qmax=350 g/kg, pH 6.5）, This was attributed to the formation of samarium complexes with the surface carboxylic moieties, available in high density on the lamellar structures of the bio-sorbent.

关键词： samarium waters activated biochar fibres enhanced sorption capacity ftir spectra rare earths

ELECTROCHEMICAL POLYMERIZATION OF ANILINE IN PHOSPHORIC ACID AND THE PROPERTIES OF POLYANILINE

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2004年第5期22卷 405-415页

作者：穆绍林 YongKong JunWu DepartmentofChemistry YangzhouUniversityYangzhou225002China

The behavior of the electrochemical polymerization of aniline in a weak acid, phosphoric acid, is very similar to that in strong acids, i.e. its polymerization rate increases quickly with the electrolysis time. The ftir spectra of polyaniline samples synthesized in phosphoric acid indicate that the counter ion H2PO4- is present in both the oxidized form and the reduced form of polyaniline. The counter ion plays an important role in adjusting the pH value at the electrode surface of polyaniline during the oxidation and reduction processes. As a result, a pair of redox peaks still appear in cyclic voltammograms of polyaniline in a solution of sodium sulfate of pH 5.5 and in a solution of NaH2PO4 of pH 7.0, respectively, at low potential scan rate; and the color of polyaniline film also changes with applied potential at pH 7.0. Thus, the pH region for the electrochemical activity and the electrochromism of polyaniline is extended to pH 5.5 for a solution of sodium sulfate and to pH 7.0 for a solution of NaH2PO4. The conductivity of polyaniline is 3.3 S cm-1, depending on the concentration of phosphoric acid used in the stage of polymerization of aniline. The result of elemental analysis of polyaniline is presented here.

关键词： Electrochemical polymerization Polyaniline Spectroelectrochemistry ftir spectra Elemental analysis

ELECTROCHEMICAL SYNTHESIS AND PROPERTIES OF POLY(AZURE B)

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2001年第4期19卷 359-370页

作者： Dan Shan Shao-lin Mu Department of Chemistry School of Sciences, Yangzhou University Yangzhou 225002, China Yangzhou Univ Sch Sci Dept Chem Yangzhou 225002 Peoples R China

A blue poly(azure B) film has been synthesized using repeated potential cycling between -0.25 and 1.10 V (versus SCE). The electrolytic solution consisted of 2.5 mmol dm(-3) azure B, 0.5 mol dm(-3) NaCl and 0.2 mol dm(-3) NaH2PO4 at the pH range of 2.0 to 11.0. The in situ visible spectrum during electrolysis of azure B shows that the intensity at 740 nm peak increases with increasing numbers of potential cycles, which is attributable to the formation of poly(azure B). The wavelength of its corresponding absorption peak is 98 nm longer than that of azure B. The polymerization rate is strongly affected by pH values. The anodic peak potential and cathodic peak potential of the poly(azure B) in a solution of pH 3.0 are not affected by increasing the scan rate from 25 to 600 mV s(-1). Poly(azure B) has good electrochemical reversibility and fast charge transfer characteristic in the pH range of 2.0 and 11.0. The conductivity of poly(azure B) is 1.5 x 10(-4) S cm(-1) According to the differences between ftir spectra of poly(azure B) and azure B, an electrochemical polymerization mechanism of azure B is proposed in this paper.

关键词： azure B electrochemical polymerization electrochemical properties conductivity in situ UV-visible spectra ftir spectra

Investigation on the cleaning of KDP ultra-precision surface polished with micro water dissolution machining principle

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2017年第1期60卷 27-35页

作者： CHEN YuChuan GAO Hang WANG Xu GUO DongMing TENG XiaoJi Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education School of Mechanical Engineering Dalian University of Technology Dalian 116023 China

A potassium dihydrogen phosphate(KDP) optical crystal was machined to an ultra-precision surface with water-in-oil(W/O) micro emulsion polishing fluid. The micro water dissolution principle utilized in the machining process is discussed, its planarization mechanism is illustrated, and an ultra-precision polished surface with 2.205 nm RMS roughness is obtained. However, a substantial quantity of residual contamination remained on the polished surface after machining. This can seriously impact the optical performance of the crystal, and so it must be removed. Fourier transform infrared(ftir) spectroscopy was used to conduct an investigation into the composition of the surface residue, and the results showed that the residue was comprised of organic chemicals with hydrocarbon chains and aromatic ether, i.e., mostly the polishing fluid. The cleaning method and the principle on which the KDP ultra precision surface investigation is based are discussed in detail, and the cleaning experiments with selected KDP-compatible organic solvents were then performed. ftir transmittance spectra measurement and microscopic observations were employed to assess the effects of the cleaning process on the surface of the KDP crystal. The results showed that toluene cleaning achieved the most desirable results. This cleaning method produced a surface roughness of 1.826 nm RMS, which allows the KDP crystal to be applied to subsequent engineering applications.

关键词： KDP optical crystal micro water dissolution machining micro emulsion fluid ultra-precision surface ftir spectra surface residue cleaning

Electrochemical Polymerization of Brilliant Cresyl Blue and Properties of the Polymer

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2002年第6期20卷 583-590页

作者：杨一飞穆绍林 Department of Chemistry School of Science Yangzhou University Yangzhou Jiangsu 225002 China

The electrochemical polymerization of brilliant cresyl blue (BCB) has been carried out using cyclic voltammetry in the potential region between -0.20 V and 1.15 V (vs. Ag/AgCl with saturated KCl solution). The electrolytic solution consisted of BCB (0.1 mol/L) and Na 2HPO 4 (0.2 mol/L) with pH 2.1. BCB can not be polymerized at pHftir spectrum and Raman spectrum of poly(BCB) are different from those of BCB.

关键词： electrochemical polymerization poly(brilli^an^t cresyl blue) electrochemical properties visible spectra ftir spectra Raman spectra

Solvation number, thermochemical parameter, and viscosity study of sweeteners in aqueous and non-aqueous media through ultrasonic measurements

在线全文

学校读者我要写书评

暂无评论

ChemPhysMater 2023年第4期2卷 303-314页

作者： J.H.Rakini Chandrasekaran S.Nithiyanantham Centre for Research-Department of Physics Arignar Anna Government Arts CollegeMusiri 621211India PG and Research Department of Physics Vi.Kalyanansundaram Govt Arts&Science CollegeBharathidasan UniversityThiruvarur 610003India

Ultrasonic velocity measurements are used to elucidate various aspects of solvation chemistry,including solute–solute and solute–solvent ***,an attempt is made to study a behavior of two sweeteners,D-fructose and D-sorbitol,in aqueous and non-aqueous media was attempted.D-fructose is a simple sugar found in many foods and can be consumed by diabetics and people suffering from hypoglycemia.D-Sorbitol is a sugar substitute used in diet foods,sugar-free chewing gum,mints,cough syrups,mouthwash,toothpaste etc.,D-sorbitol is an excellent humectant and texturizing agent that is also used in other products such as pharmaceuticals and *** interactions between the solute and solvent molecules are explained in terms of the solvation numbers of both aqueous and non-aqueous solutions of D-fructose and *** viscosity study correlates the viscosity of the solution with solvation;here,density,ultrasonic velocity,and viscosity of aqueous and non-aqueous solutions at various concentrations are measured at different temperatures ranging from 35 to 55℃.These parameters provide sufficient information on the interaction between molecules that may aid chemists in analyzing the mechanisms of the behavior of D-fructose and D-sorbitol in water and the water–ethanol medium through which they are *** Fourier transforms infrared spectra of pure solvent,salt,and their solutions were recorded and analyzed for confirmation.

关键词： Ultrasonic velocity Density Viscosity Solvation number Thermochemical parameters Molecular interactions ftir spectra

Comparative Structural and Spectroscopic Characterization of M^ILn^IIITiO4 Ion-exchanged Phases,with M^I： Na, H, K

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Chemistry and Chemical Engineering 2016年第1期10卷 1-6页

作者： Araceli Elisabet Lavat Claudia Cecilia Wagner CIFICEN (Centre of Investigations in Physics and Engineering of the Centre of Buenos Aires Province) CONICET-UNCPBA (National Council of Scientific and Technical Research Faculty of Engineering National University of the Centre of Buenos Aires Province) Olavarria B7400 JW1 Argentina

In this paper, a comparative study of the XRD characterization and ftir spectroscopic behavior of some M^ILn^IIITiO4 phases with M^I： Na, H, K and Ln^III, the trivalent lanthanides elements： Sm, Eu, Er and Yb is reported. The H and K- oxides were obtained by ion-exchange from NaLnTiO4. These ternary oxides belong to the K2NiF4 structural type, with the M^I and Ln^III cations distributed in an ordered way on the K-sub lattice. The ftir spectra of the materials were analyzed by comparison with structurally related materials. A close relationship with the parent NaLnTiO4 was found.

关键词： NaLnTiO4 ion-exchange X-ray characterization ftir spectra

Proximate composition,mineral contents,phytochemical constituents,antimicrobial activities and Fourier transforms infrared spectroscopy analysis of bark,stem and seed of Hippophae rhamnoides Linn

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Coastal Life Medicine 2015年第6期 486-490页

作者： Javid Ali Bashir Ahmad Said Hassan Muhammad Siddique Farrah Gul Shafaat Ullah Center of Biotechnology and Microbiology University of PeshawarKPKPakistan PCSIR Laboratories Complex Jamrud Road PeshawarKPK-Pakistan

Objective:To compare the proximate composition,mineral contents,antimicrobial,phytochemical and Fourier transforms infrared(ftir)spectroscopy analysis of bark,stem and seed of Hippophae ***:Proximate composition was determined according to the described *** analysis was carried out by atomic absorption spectroscopy and flame *** activities were evaluated according to the agar well diffusion *** qualitative analysis was carried out according to the described methods and functional groups were determined by ftir Prestige-21 Shimadzu ***:The proximate analysis showed high content of protein and fiber in stem and *** content of Na(900 mg/L)and K(670 mg/L)was found in bark powder,while in seed,high contents of Ca(800 mg/L),Mg(725 mg/L),Fe(250 mg/L)Zn(90 mg/L)and Mn(65 mg/L)were found compared to stem and ***,flavonoids and tannins showed high contents in stem and bark of all *** bark aqueous extract showed high zone of inhibition against Staphylococcus aureus(21 mm)and Escherichia coli(20 mm),while methanol extract of stem showed high zone of inhibition(14 mm and 13 mm)against Enterococcus faecalis and Escherichia coli *** aqueous extract of bark documented high zone of inhibition against Aspergillus niger(21 mm)and Aspergillus parasiticus(20 mm).ftir spectra revealed the presence of OH,C-O and C=O functional ***:The study concludes that bark,stem and seed extracts will be useful guideline for the new syntheses of feed,food supplements and herb drugs with various combination,which can be used for the treatment of many diseases at global level especially in tropical regions as well as the male nutrition problems in these areas.

关键词： Seabuckthorn Proximate composition Minerals Antibacterial Antifungal ftir spectra