bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemical Constituents from the Leaves of Zanthoxylum Schinifolium
Authors: Cheng Ming‐Jen , Yang Cheng‐Hui , Lin Wen‐Yu , Lin Wei‐Yu , Tsai Ian‐Lih , Chen Ih‐Sheng 
Published: May 2015

Abstractcis‐Fagaramide (1), a new amide, together with fifty known compounds, have been isolated from the leaves of Zanthoxylum schinifolium. These known compounds include twenty‐one coumarins, eleven alkaloids, one furan, four benzenoids, three chlorophylls, four triterpenoids, one diterpenoid, one sesquiterpenoid, and four steroids. The structures of these compounds were determined by means of spectral analyses.
Sesquiterpenes from Ligularia Hodgsonii
Authors: Liao Jian‐Chun , Zhu Qi‐Xm , Yang Xiu‐Ping , Jia Zhong‐Jian 
Published: May 2015

AbstractA new nor‐sesquiterpenoid eremophilane derivative and a new eudesmane derivative were isolated from the whole plants of Ligularia hodgsonii. Their structures were elucidated by spectroscopic methods and 2D NMR techniques.
Advent and Progress of Spin Chemistry
Authors: Hayashi Hisaharu 
Published: May 2015

AbstractThe field of Spin Chemistry includes various subjects concerned with the influence of magnetic fields on chemical and biochemical reactions such as magnetic field and magnetic isotope effects (MFE and MIF) and chemically induced dynamic nuclear and electron polarization (CIDNP and CIDEP). Although this field started in the middle 1960s, it has been expanding now and has established its identity as one of the most promising research areas in the 21st century. The first half of this review shows how the field of Spin Chemistry was brought about from a veil of secrecy. This review also shows how the author's group has contributed to the advent and progress of Spin Chemistry. The second half of this review introduces the recent results obtained by the author's group for the MFEs on photo chemical reactions in solution with a pulsed‐magnet (maximum field ∼ 30 T), a pico second‐laser photolysis apparatus, and higher spin species than S = 1.
Extraction Behaviour of Cyanex‐923 and Cyanex‐471X Towards the Rhodium(III) from Bromide Media and Its Separation from other Platinum Metals
Authors: Duche S. N. , Chavan D. V. , Dhadke P. M. 
Published: May 2015

AbstractThe extraction of Rh(III) from bromide media with Cyanex‐923 and Cyanex‐471X in toluene was studied. The quantitative extraction of Rh(III) with extractants was found by studying the different parameters like, hydrobromic acid concentration, extractant concentration, diluents and effect of temperature on extraction. The optimum condition was [HBr] = 1.0–1.5 moll−1, [SnCl2] = 0.2 moll−1 with [Cyanex‐923] = 0.15 moll−1, while it was [HBr] = 1.5–2.0 moll−1, [SnCl2] = 0.4 moll−1 with [Cyanex‐471X] = 0.8 moll−1 in toluene. The quantitative extraction was observed only in the presence of SnCl2 for both extractants. The complete recovery of Rh(III) from the Cyanex‐923 extracted organic phase was observed with the 1:1 mixture of (4.0 moll−1 HCl + 2.0 moll−1 HNO3), and that with the Cyanex‐471X extracted organic phase was found with 1:1 mixture of (2.0 moll−1 H2SO4 + 1.0 moll−1 KMnO4). Stoichiometric ratio of Rh(III) with both extractants was 1:1. The proposed methods were employed for extraction and separation of Rh(III) from other platinum metal ions and also for recovery of Rh(III) from a synthetic solution of spent autocatalysts.
Electrochemical Study of Schiff Bases by Means of Self‐Assembled Monolayers
Authors: Dmg Keqiang , Wang Qingfei , Jia Zhenbm , Tian Na , Wang Ning , Tong Ruting , Wang Xinkui , Shao Huibo 
Published: May 2015

AbstractIn this paper, Schiffbases were investigated using cyclic voltammetry (CV) and impedance electrochemical spectroscopy (EIS) techniques by means of self‐assembled monolayers for the first time, where a 0.1 M KCl solution and the redox couple of Fe(CN)63−/Fe(CN)64−were used as the electrolyte and probing‐pin, respectively. The monolayers formed by the employed Schiff base were proved to be relatively stable, and its electrochemical response in the studied system with different pH values was also de scribed clearly with CV and EIS plots. The results show that the monolayer of Schiff bases could exist in the solution with pH value from 2 to 10. In the EIS measurement in the concentration range from 10−5 M to 5× 10−4 M, a nearly linear relation ship between the charge transfer resistance (Rct) and the logarithm concentration of Cu2+was observed, suggesting that Cu2+ could be titrated with the EIS method quasi‐quantitatively. The phenomenon agreed with the former report very well. Using the self‐assembled monolayers to study Schiff bases with the electrochemical method is the major contribution of our work.
Synthesis of New Reagent 2‐Acetylthiophenethiocynate and its Use in Extraction of Pt(IV) Spectrophotometrically
Authors: Chaudhary Avinash Baliram , Shrinivasan Nirupa , Lokhande Rama Sadashiv 
Published: May 2015

Abstract2‐Acetyl thiophenethiocynate (ATT) was synthesized and its characterization study was carried out using elemental analysis, IR and NMR techniques. The new reagent was proposed as an extractant for the development of the extractive spectrophotometric method for determination of Pt(IV) metal. The reagent complexes with the metal to produce a yellow colored complex which was then extracted into ethyl acetate at pH 11.2–11.6 having an absorption maxima at 400 nm. The thermal study showed that the extraction reactions are exothermic in nature with the reagent, and the stoichiometric ratio of Pt(IV) to 2‐acetyl thiophenethiocynate in the organic phase was 1:2. The method permits separation and determination of platinum from real and binary mixtures. The separation of Pt(IV) from bivalent metal ions has been also studied.
Studies on the Reaction of α‐Chloroformylarylhydrazine Hydrochloride1 with N‐Heterocyclic Compounds
Authors: Chiu Chun‐Yen , Kuo Chao‐Nan , Kuo Wen‐Fa , Yeh Mou‐Yung 
Published: May 2015

AbstractIn addition to pyridines, α‐chloroformylarylhydrazine hydrochloride 1 can also react with some N‐heterocyclic compounds. The cycloaddition of 1 with isoquinoline was achieved to obtain 3. The production of 4, 5, 6 given by cycloaddition of 1 with pyridazine was de pendent on the reaction condition. Some heterocyclic compounds bearing an X‐C=N (X:S, N) group on the ring can react with 1 to gain the derivatives of 2,4‐dihydro‐1,2,4‐triazol‐3‐one. 7, 8, 9 and 10 were given by reaction of 1 with 1,3,5‐triazine, 1,4,5,6‐tetrahydropyrimidine, 1,3‐thiazole and 2‐amino‐1,3‐thiazole, respectively. The reactions for 2‐amino‐1,3,4‐thiadiazole and 3‐amino‐1,2,4‐triazole had the same product 11.
Synthesis and Characterization of Transition Metal Complexes of Potassium 3‐(Pyridine‐4‐Carbonylmethyl)‐Dithiocarbazate
Authors: Liu Dong , Liu Su‐Yan , Yang Xin‐Ping , Xu Peng‐Fei , Zhang Zi‐Yi 
Published: May 2015

AbstractThe preparation and characterization of some dipositive metalion complexes de rived from potassium 3‐(pyridine‐4‐carbonylmethyl)‐dithiocarbazate (PCDHK) are reported. The solid complexes of the composition ML·nH2O (M=Cu(II), Co(II), Mn(II), Zn(II), Cd(II), Ni(II), Pb(II), L = PCD−2, n = 0, 1, PCD−2=PCDHK‐K+‐H+) and ML2·2H2O (M=UO2(IV), L=PCDH−1, PCDH−1=PCDHK‐K+) have been characterized by elemental analyses, IR, UV, and 1HNMR spectra. The IR spectral data indicate that PCDHK be haves as either a mononegative or binegative ligand and coordinates in a tridentate or bridging tetradentate manner.
Chemical Components from Leontopodium Nanum
Authors: Wang Ying , Zhu Qi‐Xiu , Yang Min , Jia Zhong‐Jian 
Published: May 2015

AbstractPhytochemical investigation of the whole plant of Leontopodium nanum afforded a new coumarin named leontonanin (1), together with six known compounds, umbelliferone (2), 3,4′, 7‐trihydroxyflavone (3), oleanolic acid (4), β‐sitosterol (5), daucosterol (6) and stearic acid (7). The structure of compound (1) was elucidated by spectroscopic methods including 2D‐NMR techniques.
Radicals Containing Hydrogen, Carbon and Oxygen Atoms
Authors: Bersohn Richard 
Published: May 2015

AbstractThere is much new information available on radicals containing C, H and O atoms. Indeed, most of the data discussed in this review did not exist twenty years ago. New, more powerful laser and microwave experimental techniques have greatly expanded our knowledge of the energetics, spectra, reactions and decomposition processes of these radicals. This review attempts to give a unified discussion of the radicals.
Preparation and Structure of [(η5‐C5H5)Fe(CO){C(O)Ph}2]2Li2(2,2′‐Bipyridine): A Sequential Treatment of Nucleophile Followed by Lewis Base
Authors: Liu Ling‐Kang , Peng James , Huang Candice 
Published: May 2015

AbstractUnable to elaborate (η5‐C5H5)Fe(CO)2C(O)Ph by the nucleophile/electrophile sequences, the treatment of nucleophile PhLi followed by Lewis base 2,2′‐bipyridine instead leads to the meaningful isolation of [(η5‐C5H5)Fe(CO) {C(O)Ph}2]2Li2(2,2′‐bipyridine).
Hydrous Pyrolysis of Methylphenanthrenes – Degradation and Isomerization
Authors: Wu Suh‐Huey , Wang Yane‐Shih , Fan Lian‐Xin , Chang Robert T. D. , Huang Ded‐Shih 
Published: May 2015

AbstractA simulation of the chemical transformations of methylphenanthrenes in sediment was performed using hydrous pyrolysis technique. The results indicate that isomerization is not the primary cause of the change in the MPI1 index. Rather, the degradation reaction of methylphenanthrenes to phenanthrene is one of the most likely causes reversing the trend of the MPI1 index with increasing the heating temperature. An unusual isomerization between 2‐methylphenanthrene and 9‐methylphenanthrene was also observed during the course of heating experiments. A plausible mechanism involving [1,5]‐methyl shift was proposed for this isomerization reaction.
Kinetic and Thermodynamic Parameters of the Thermal Decomposition of Some Metal Complexes of 4‐Benzamido‐3‐Thiosemicarbazone Derivatives
Authors: Emam M. E. M. 
Published: May 2015

AbstractThe kinetic and thermodynamic parameters such as reaction order, activation energy, enthalpy, free energy and entropy change related to the thermal decomposition of Co(II), Ni(II) and Cu(II) hydrazone complexes of 4‐benzamido‐1‐(4‐actylpyridine)‐3‐thiosemicarbazone (BACPT) and 4‐benzamido‐1‐(pyridine‐3‐aldehye)‐3‐thiosemicarb‐azone (BAPT) were evaluated from differential thermal analysis (DTA) curves using Thomas‐Clarke's method. The thermal stability of these complexes are discussed in relation to the nature of the metalion and of the ligand present. A suitable mechanism for the thermal decomposition process of the complexes based on the data of the thermogravimetric analysis (TGA) was suggested.
Syntheses and Structures of Zinc(II) Co‐Ordination Polymers Bridged by Flexible Bidentate Nitrogen Ligands
Authors: Suen Maw‐Cherng , Wu Ymg‐Yann , Dong Guo‐Chung , Chen Jhy‐Der , Keng Tai‐Chiun , Wang Ju‐Chun 
Published: May 2015

AbstractThe reaction of Zn(NO3)2·6H2O and bpp (bpp = 1,3‐Bis(4‐pyridyl)pronpane) in CH3OH afforded the complex [Zn(bpp)(NO3)2]n, 1. The IR has been recorded and the structure has been determined. Crystal data for 1: Space group P2(1)/n, a = 11.749(1), b = 11.413(1), c = 11.942(1) Å, β = 96.06(6)°. V = 1592.5(3) Å3, Z = 4 with final residuals R1 = 0.0484 and wR2 = 0.0984. The complexes show supramolecular structure in the solid state by intermolecular hydrogen bonding interaction.
Synthesis and Spectroscopic [Electronic, IR, NMR (1H, 13C, 89Y)] Characterization of Hexaisopropoxoniobates and ‐Tantalates of Yttrium(III) and Lanthanides(III)
Authors: Mishra Shashank , Tripathi Upendra M. , Singh Anirudh , Mehrotra Ram C. 
Published: May 2015

AbstractHexaisopropoxoniobates/tantalates of lathanides of the type [Ln{(μ‐OPri)2M(OPri)4}3] (M = Nb, Ln = Y(1), La(2), Nd(3), Er(4), Lu(5); M = Ta, Ln = Y(6), Gd(7)) have been prepared by the reactions of LnCl3.3PriOH with three equivalents of KM(OPri)6 in benzene. Reactions in 1:2 molar ratio of LnCl3.3PriOH with KTa(OPri)6 yielded derivatives of the type [{(PriO)3Ta(μ‐OPri)3}Ln{(μ‐OPri)2Ta(OPri)4}(Cl)] (Ln = Y(8), Gd(9)), which on interactions with one equivalent of KOPri afforded [{(PriO)3Ta(μ‐OPri)3}Ln {(μ‐OPri)2Ta(OPri)4}(OPri)] (Ln = Y(10), Gd(11)). All these derivatives have been characterized by elemental analyses and molecular weight measurements as well as by their spectroscopic [IR, 1H and 13C NMR (Y, La, Lu), electronic (Nd, Er)] studies. 89Y NMR studies have also been carried out on derivatives (6), (8), and (10).
2‐Aminocyclopentene‐1‐Dithiocarboxylic Acid‐Naphthalene Adsorbent for the Preconcentration and Determination of a Trace Copper in Real Samples by Spectrophotometric Method
Authors: Gholivand Mohammad B. , Sobhani Shahin , Khirdoosh Fahimeh 
Published: May 2015

AbstractA solid uncharged complex produced from 2‐aminocyclopentene‐1‐dithiocarboxylic acid (synthetic reagent) on naphthalene provides a very sensitive, selective and economical method for the preconcentration and determination of trace amounts of copper in drug and alloy samples. The 2‐aminocyclopentene‐1‐dithiocarboxylate of copper is retained quantitatively on microcrystalline naphthalene in the pH range 2.8–3.3. After filtration the solid mass consisting of copper complex‐naphthalene is dissolved with 4 mL of dimethylformamide (DMF). The absorbance is measured at 462 nm with a spectrophotometer against the reagent blank and molar absorptivity found to be 2.8 × 105 liter mol−1 cm−1. Beer's law is obeyed over the concentration range of 0.1–16.0 μg of copper in 4 mL of the dimethylformamide solution.Detection limit is 3 ng mL−1 [signal to noise ratio = 2]. Ten replicate determinations on a sample containing 1 μg of copper gave a relative standard deviation of 0.76%. The interference of a large number of anions and cations have been studied and the optimized conditions developed were utilized for determination of copper in various real samples.
Chiral Liquid Crystals Synthesized from 2(S)‐[2(R)‐Methylhexyloxy]Propanol and its (S,S)‐Diastereomer
Authors: Lee Hui‐Chen , Hsie Ming‐Jing , Yeh Shu‐Wen , Cheng Pao‐Swu , Tsai Wen‐Liang 
Published: May 2015

AbstractTwo new chiral alcohols, 2(S)‐[2(R)‐methylhexyloxy]propanol (5) and 2(S)‐[2(S)‐methylhexyloxy]propanol (6), were prepared from the corresponding propionic acid ethyl ester 1 and 2 in the presence of sodium borohydride. They were used as the chiral moiety for the synthesis of two diastereomeric liquid crystals 7 and 8. Both of them exhibit the phase sequence I‐SmA‐SmC*‐SmX‐Cr. The mesogenic properties of the (S,S)‐diastereomer 8 are more unique in comparison with those of the (S,R)‐diastereomer 7. It possesses not only lower SmA and SmC* phase transition temperature, 103 °C vs. 112 °C for SmA phase and 31 °C vs. 65 °C for SmC* phase, but wider SmA and SmC* phase range, 40 °C vs. 31 °C for SmA phase and 72 °C vs. 47 °C for SmC* phase. The diastereomer 8 also has a larger Ps value than that of 7, 24 vs. 15 nC cm−2 measured at Tc ‐ T = 10 °C. The difference in these mesogenic properties is discussed by comparing their conformation difference at the molecular part of benzoate.
Synthesis of Some New Fused/Spiroheterocyclic Compounds Incorporating Quinone Compounds
Authors: Khalafallah A. K. , El‐Aal R. M. Abd , Kanzi N. A. A. El 
Published: May 2015

AbstractA series of fused and spiro pyrazolones, isoxazolines, pyrimidines, β‐lactams, and thiazolidinones incorporating 4‐amino‐2‐methyl‐5,10‐dioxo‐1,5,10,11‐tetrahydrobenz[g]quinoline 3‐carbonitrile 1 and 4‐amino‐2‐methyl‐5,6,11‐trioxo‐1,4,4a,5,6,11,12,12a‐octahydro‐1,12‐diazanaphthacene 3‐carbonitrile 2. 7,8a‐c, 15,16a‐c, 19,20a‐d, 21,22a‐d, have been synthesised by cyclocondensation addition reaction and cycloaddition reaction of hydrazines, hydroxylamine, urea, thiourea, monochloroacetyl chloride and mercaptoacetic acid with the synthesised 15,16a‐c and 17,18a‐c.
A Simple and Efficient Method for the Oxidation of Aryl Substituted Semicarbazide with NaNO2/NaHSO4·H2O/SiO2 under Mild Conditions
Authors: Li Xiao‐Chuan , Wang Yu‐Lu , Wang Jin‐Ye 
Published: May 2015

AbstractIn this paper, eighteen aryl substituted semicarbazide underwent efficient oxidation to aryl azo compounds using NaNO2/NaHSO4·H2O/SiO2 under mild conditions with excellent yields.
Antimicrobial Activity of Some Novel Thiourea, Hydrazine, Fused Pyrimidine and 2‐(4‐Substituted)anilinobenzoazole Derivatives Containing Sulfonamido Moieties
Authors: El‐Gaby Mohamed S. A. , Micky Jehane A. , Taha Nadia M. , Sh. El‐Sharief Marwa A. M. 
Published: May 2015

AbstractThiophosgenation of sulfonamides 1a‐c in the presence of dilute HCl at room temperature furnished the isothiocyanatosulfonamides 2a‐c and treatment with aromatic amines gave 1,3‐disubstituted thioureas 3a,b. Also, interaction of two molecules of 2c with 1,4‐phenylenediamine yielded the novel bisthiourea 4. Cyclocondensation of 2 with ortho amino carboxylic acid compounds such as anthranilic acids 8, 5‐amino‐1‐phenyl‐pyrazol‐4‐carboxylic acid 9 and 4,5,6,7‐tetrahydro‐2‐amino‐benzo[b]thiophene‐3‐carboxylic acid 10 furnished the fused thiopyrimidines 11a‐d, 12 and 13, respectively. 2‐Anilinobenzoazole derivatives 15a‐c, 16a, b and 17a,b were obtained through cyclocondensation of 2 with 1,2‐dinucleophiles.
Cytotoxic Components from the Leaves of Schefflera Taiwaniana
Authors: Kuo Yueh‐Hsiung , Lo Jir‐Mehng , Chan Yih‐Fwu 
Published: May 2015

AbstractThe isolation and identification of eighteen components from the leaves of Schefflera taiwaniana are presented. Their structures were determined on the basis of spectral data as well as direct comparison with authentic samples. These compounds include two polyacetylenes, one carotenoid‐like, three sesquiterpenes, one diterpene, four triterpenes, two tocopherols, and five alkyl 4‐hydroxycinnamate mixtures. Among these, 4‐hydroxy‐trans‐cinnamic acid docosyl ester and 4‐hydroxy‐cis‐cinnamic acid tetracosyl ester are new compounds. Some of these components exhibit cytotoxic activity.
Chemical Constituents of the Aerial Part of Celastrus Hypoleucus
Authors: Wang Hong , Tian Xuan , Chen Yao‐Zu 
Published: May 2015

AbstractFourteen compounds including eight triterpenoids, 12‐oleanaen‐3β‐ol (β‐amyrin) (1), 12‐oleanaen‐3β‐caffeate (2), 9(11),12‐oleanadien‐3β‐ol (3), 9(11),12‐oleanadien‐3‐one (4), 9(11),12‐oleanadien‐3 β‐caffeate (5), friedela‐3‐one (friedelin) (6), friedela‐3‐one‐29‐ol (7), and 12‐gammateraen‐3 β‐ol (tetrehymanol) (8); one steroid, β‐sitosterol (9); one long‐chain acid, octadecadienoic acid (10); two esters, ester of n‐octaolecyl‐4‐hydroxy‐cinnamate (11), and ester of n‐octadecyl‐caffeic acid (12); one diterpene, 8β,19‐dihydroxy‐3‐oxopimar‐15‐ene (13); one sesquiterpene, 1β,2β,9α‐trihydroxy‐β‐dihydroagarofuran (14) were isolated from the aerial part of Celastrus hypoleucus. These compounds were characterized and identified by physical and spectral methods. All compounds were isolated for the first time from this plant. Among them 12‐oleanaen‐3β‐caffeate (2) and 9(11),12‐oleanadien‐3β‐caffeate (5) are two new compounds, and ester of n‐octadecyl‐caffeic acid (12) possessed antilipoperoxidative effect by specifically scavenging the hydroxyl free radical (•OH) in vitro.
Studies on Chemical Constituents of Salix Matsudana
Authors: Wang Jin‐Xin , Zheng Shang‐Zhen , Sun Li‐Ping , Shen Xu‐Wei , Li Ying 
Published: May 2015

AbstractTwo new phytane‐type diterpene‐γ‐lactones named Hanliuin III (3) and Hanliuin IV (4), together with two previously reported diterpenes, six known flavonoids and five other known compounds were isolated from Salix matsudana. The structures of two new compounds were deduced from spectroscopic methods and 2D NMR techniques.
Bioorganic Studies on Rhodopsins
Authors: Nakanishi Koji , Berova Nina , Fishkin Nathan , Fujioka Naoko 
Published: May 2015

AbstractA summary of ongoing bioorganic studies on rhodopsin, the most intensively studied G‐protein coupled receptor (GPCR) is given. The article includes: (i) general descriptions of rhodopsin and (ii) various naturally occurring retinal chromophores in animals, fish and microorganisms; (iii) the rationale for 6‐s‐cis‐11‐sicis retinal being the common chromophoric structure in visual pigments; (iv) electrostatic charge distribution within the opsin binding site; (v) the visual transduction cycle; and (vi) the changes occurring in the chromophore/receptor interactions allong the visual transduction path.
Synthetic Chemistry and Function of Bacterial Cell Surface Glycoconjugates
Authors: Kusumoto Shoichi , Fukase Koichi , Oikawa Masato , Suda Yasuo 
Published: May 2015

AbstractTypical bacterial glycoconjugates are known to stimulate immunological systems of higher animals and thereby play important roles in the primary defense of animals against bacterial infection. Lipopolysaccharide (LPS) of gram‐negative bacteria is a representative of such glycoconjugates. LPS was first discovered as a potent bacterial toxin and named endotoxin but was soon found to exhibit immunostimulating activity. By the use of our synthetic pure preparations, the lipophilic partial structure of LPS, designated lipid A, proved to be the active entity responsible for both endotoxic and immunostimulating activities of LPS. This paper deals with our recent chemical synthesis and functional study of lipid A and related compounds. Synthesis is described of its various structural analogues, radio‐labeled compound and Re‐type LPS that contains two additional sugar moieties linked to lipid A.
Syntheses, Fluxional Behavior and Crystal Structures of the Endo and Exo η3‐Allyl Monocarbonyl Dithiocarbonate and Dithiocarbamate Molybdenum Complexes: Crystal Structures of exo‐[Mo(η3‐allyl)(η2‐S2COC2H5)(CO)(η2‐dppm)]and endo‐[Mo(η3‐allyl)(η2‐S2CNC4H8)(CO)(η2‐dppe)]
Authors: Yih Kuang‐Hway , Lee Gene‐Hsiang , Wang Yu 
Published: May 2015

AbstractThe novel endo and exo complexes [Mo(η3‐C3H5)(η2‐L2)(CO)(η2‐dppm)] are accessible by the reactions of the complexes [Mo(η3‐C3H5)(CO)2(η2‐L2)(X)] (L2, X = S2COEt, CH3CN; S2CNC4H8; S2CNEt2) with dppm. X‐ray crystal structures of exo‐2 and endo‐5 have been employed to elucidate the two orientations.
Matrix Effect of Alkali and Alkaline Earth Metal Halides on Fluorescence Quantum Yield of Indium in Laser‐Induced Fluorescence Flame Spectrometry
Authors: Ke Ching‐Bin , Lin King‐Chuen 
Published: May 2015

AbstractAs interfered with by alkali and alkaline earth metal halides added as the matrix in an acetylene/air flame, the fluorescence quantum yield of In as the analyte in a laser‐induced fluorescence (LIF) flame spectrometry has been thoroughly characterized. The fluorescence quantum yield is determined by a ratio of F to A, where F is the measured fluorescence of In and A is the difference between the absorption signals recorded for the analyte and the blank solutions. The normalized fluorescence signal is treated to prevent deviations due to variations of the atomization efficiency under the conditions with and without the matrix added. The fluorescence quantum yield is measured to be almost independent of the matrix concentration up to 500 ppm (μg/mL) studied, under conditions of either optical unsaturation or saturation. By considering a quenching effect induced by electron‐atom collisions, the calculated fluorescence quantum yields are consistent with our observations.