bluuebunny/crossref_metadata_2025 huggingface dataset:
Cyclic Voltammetrically Prepared MnO2‐Polyaniline Composite and Its Electrocatalysis for Oxygen Reduction Reaction (ORR)
Authors: Ding Ke‐Qiang
Published: May 2015

The composite of manganese dioxide‐polyaniline (MnO2‐PANI) was successfully prepared by cyclic voltammetry (CV) from a 0.5 M H2SO4 solution containing 0.2 M aniline and 0.5 M MnSO4. Scanning electron microscopy (SEM) images revealed that cauliflower like manganese dioxides entangled with PANI were generated. The spectra obtained from UV‐vis spectrophotometry (UV‐vis) and Fourier transform infrared spectrometry (FTIR) strongly demonstrated that this novel composite was composed by MnO2 and PANI, and also there was an interaction between MnO2 and PANI. Then, for the first time, this resultant composite was modified on a graphite electrode and employed in the oxygen reduction reaction (ORR), subsequently, the obtained cyclic voltammograms (CVs) verified that ORR could proceed on this resultant composite of MnO2‐PANI. Lastly, the possible catalysis mechanism of MnO2‐PANI towards ORR was proposed based on the results we acquired. Developing a novel substrate on which ORR could proceed is the main contribution of this work.
Liquid Phase Hydrogenation of t,t,c‐1,5,9‐Cyclododecatriene over Ni/MCM‐41 and Ni/SiO2 Catalysts
Authors: Hsu Chen‐Hun , Wang Yin‐Lan , Ko An‐Nan
Published: May 2015

Ni‐loaded pure siliceous and aluminosilicate MCM‐41 (Ni/MCM‐41) and nickel‐loaded silica (15Ni/SiO2) were synthesized via wet impregnation and were characterized by various techniques. The H2 consumption in the TPR analysis was found to be proportional to the Ni amount in the calcined samples. After reduction the average Ni particle sizes of 15Ni/MCM‐41 and 15Ni/SiO2 were 9–12 and 16 nm, respectively, by means of XRD and TEM measurements. All catalysts owned weak and intermediate Lewis acid sites that increased slightly with increasing the Ni amount and the Al content. In the liquid phase hydrogenation of t,t,c‐1,5,9‐cyclododecatriene over Ni/MCM‐41, the catalytic activity was parallel to the Ni content and enhanced slightly with the acid amount of the catalysts. Consequently, it was proposed that the Ni metallic sites contributed the major effect to the catalytic activity while the Lewis acid sites promoted a small but significant influence on the catalytic performance. It is noteworthy that all 15Ni/MCM‐41 catalysts exhibited remarkably higher activity than that of the conventional 15Ni/SiO2 catalyst.
Purification and Characterization of Bowman‐Birk Protease Inhibitor from Rice Coleoptiles
Authors: Yan Ker‐Ming , Chang Tschining , Soon Su‐An , Huang Fu‐Yung
Published: May 2015

A 15 kDa rice Bowman‐Birk inhibitor from fast elongating coleoptiles has been purified and identified using partial N‐terminal sequence, LC‐MS, and MALDI‐TOF MS as a 133 amino acid polypeptide (BBIrc 1). The kinetic study shows this protease inhibitor displays competitive inhibition toward trypsin with Ki of 4.0 × 10−7 M and non‐competitive inhibition toward α‐chymotrypsin with Ki of 9.3 × 10−6 M. The Western blotting results of the anti‐sera raised against this 15 kDa protein showed that this anti‐serum recognized two BBI proteins with molecular size around 15 kDa (BBIrc 1) and 25 kDa (BBIrc2) and the quantity of the expression of 15 kDa was nearly constant under both aerobic and hypoxia conditions; however, the 25 kDa expression was greatly up‐regulated when the fast elongating coleoptiles were transferred from hypoxia conditions to the aerobic conditions. The results indicate that the expression pattern of BBIs proteins correlated to the developmental stage in terms of morphological changes. The partial N‐terminal sequence of the first 9 amino acids of 25 kDa was AEAPPRPPK, which is the same as the amino acid sequence of 37th to 45th of RBBI3‐1 and LC‐MS study shows that several mass fragments fit to RBBI3‐1. The 25 kDa protein also shows specific binding to bovine trypsin. This expression pattern demonstrates for the first time that environmental factor, oxygen, can select and enhance specific BBI gene expression. The results of this study suggest BBI proteins might play multiple biological functions inside rice coleoptiles.
Determination of Sulfur Compounds in Water Samples by Ion Chromatography Dynamic Reaction Cell Inductively Coupled Plasma Mass Spectrometry
Authors: Lin Liang‐Yen , Jiang Shiuh‐Jen
Published: May 2015

An ion chromatography‐inductively coupled plasma mass spectrometric (IC‐ICP‐MS) method for the speciation of sulfur compounds, namely sulfite [SO32−], sulfate [SO42−] and thiosulfate [S2O32−], was described. Ionic sulfur compounds were well separated in about 3 min by ion chromatography with a Hamilton PRP‐X100 column as the stationary phase and 60 mmol L−1 NH4NO3 and 0.1% v/v formaldehyde (HCHO) solution (pH = 7) as the mobile phase. The analyses were carried out using dynamic reaction cell (DRC) ICP‐MS. The sulfur‐selective chromatogram was determined at m/z 48 as 32S16O+ by using its reaction with O2 in the reaction cell. The method avoided the effect of polyatomic isobaric interferences at m/z 32 caused by 16O16O+ and 14N18O+ on 32S+ by detecting 32S+ as the oxide ion 32S16O+ at m/z 48, which is less interfered. The detection limit of various species studied was in the range of 3.6–4.6 ng S mL−1. The accuracy of the method has been verified by comparing the sum of the concentrations of individual sulfur compounds obtained by the present procedure with the total concentration of sulfur in several natural water samples. The recovery was in the range of 97–102% for various compounds studied.
Functional Dihydro‐1H‐Imidazole Derivatives for MALDI Signal Enhancement of a Lysine‐Specific Chemical Modification
Authors: Ho Ming‐Yi , Shieh Yu‐Tse , Liao Chung‐Lin , Chen Yau‐Hung , Cheng Chien‐Chung
Published: May 2015

The enhancement of signal sensitivity and quantification of low‐abundance proteins is of great importance in proteomic analysis. The preparation of 2‐methoxy‐4,5‐dihydro‐1H‐imidazole (MeO‐DHIM) derivatives was accomplished by one‐step synthesis of O‐methyl‐isourea. The signal enhancement induced by these attached moieties increases in an order of compound 1 ≈︁ 4 < 2 < 5 ≈︁ 6 < 3 in MALDI mass spectrometry. Peptide‐compound 3 adduct was approximately 20 times signal enhancement of the unmodified peptide and of 9 times of the peptide‐compound 1 adduct. This result demonstrates that the rational designed organic molecules are capable of providing a sensitive tool in the detection of low‐abundance proteins in proteomics.
A Simple and Efficient Procedure for Synthesis of Optically Active 1,2,4‐Triazolo‐[3,4‐b]‐1,3,4‐Thiadiazole Derivatives Containing l‐Amino Acid Moieties
Authors: Foroughifar Naser , Mobinikhaledi Akbar , Ebrahimi Sattar , Fard Mohammad Ali Bodaghi , Moghanian Hassan
Published: May 2015

Some new and optically active 1,2,4‐triazolo thiadiazoles bearing N‐phthaloyl‐l‐amino acids were synthesized by reaction of 4‐amino‐5‐(3‐ or 4‐)pyridyl‐3‐mercapto‐(4H)‐1,2,4‐triazoles with N‐phthaloyl‐l‐amino acids in the presence of phosphorus oxychloride. All the newly synthesized compounds were confirmed by IR, 1H NMR, 13C NMR and elemental analysis.
Study on Electrocatalytic Activity of Platinum for Hydrogen Oxidation in Acidic Solution by Scanning Electrochemical Microscopy
Authors: Yin Yue‐Hua , Niu Lin , Cao Xiao‐Li
Published: May 2015

The electrocatalytic activity of platinum for hydrogen oxidation in 0.01 M H2SO4 + 0.1 MNa2SO4 solution has been investigated by scanning electrochemical microscopy (SECM) technique. The cyclic voltammogram (CV), approach curve, area scan imaging and chronoamperometric methods have been used. The results indicate that the imaging capability of the SECM feedback mode can be used more efficiently to visually identify materials' electrocatalytic activity, compared with the approach curve method for identification of the conductive or insulating nature of a surface. The SECM imaging method has demonstrated the effects of Pt substrate potential on the electrocatalytic oxidation of hydrogen under a constant tip potential. It is found that the more positive the Pt substrate potential, the lower the electrocatalytic activity of the Pt. Furthermore, the chronoamperometric results support the variation of the electrocatalytic activity with the Pt substrate potential as well.
Structures and Magnetic Properties of Two Copper(II) Complexes with 2,5‐Dichloro‐3,6‐Dihydroxy‐1,4‐Benzoquinone Dianionic and Tetrachloroquinone Ligand
Authors: Chung Yun‐Ho , Fang Szu‐I , Fang Shu‐Hui , Lin Hsin‐Huang , Liou Shyh‐Yeon
Published: May 2015

The polynuclear copper(II) complex [Cu2(Hdpa)2(μ‐ClDHBQ)(ClO4)2]n, 1 is bridged by ClDHBQ−2 (2,5‐dichloro‐3,6‐dihydroxy‐1,4‐benzoquinone dianionic) and 2,2′‐dipyridylamine (Hdpa). In the axial position, Cu is connected with the oxygen atom of ClO. The perchlorate anion may be envisaged as a monodentate O‐bound ligand. Through the bond bridge of O–Cu … O–Cl, the binuclear compound [Cu2(Hdpa)2(μ‐ClDHBQ)(ClO4)2] is strung together into a long chain compound. Tetrachlorocatechol underwent partial oxidation/hydrolysis/dechlorination processes to produce ClDHBQ−2.

The other mononuclear complex [Cu(Hdpa)(TeCQ)](DMF), 2, in which tetrachloroquinone (TeCQ) was produced by oxidation of tetrachlorocatechol (TeCC), therefore complex 2 is in the quinone form.

The magnetic susceptibility measurements show antiferromagnetic coupling with J = −11.9 cm−1, θ = 2.6 K, and g = 2.05 for complex 1. Complex 2 exhibits the typical paramagnetic behavior of s = 1/2.
Differential Pulse Polarographic Determination of Cd(II) and Pb(II) in Milk Samples after Solid‐Phase Extraction Using Amberlite XAD‐2 Resin Modified with 2,2′‐DPED3P
Authors: Sreedhar N. Y. , Prasad P. Reddy , Nayak M. Sankara , Rekha D. , Reddy C. Nageswara
Published: May 2015

In the present paper novel column solid phase extraction procedure was developed for the determination of Cd(II) and Pb(II) in cows', goats', ewes', buffalos' and humans' milk samples using newly synthesized reagent 2,2′‐DPED3P (2,2′‐{[1,2‐diphenylethane‐1,2‐diylidene]dinitrilo}diphenol) for preconcentration and separation prior to differential pulse polarography using amberlite XAD‐2 in the ranges of pH 4.0–5.0. The sorbed elements were subsequently eluted with 10 mL of 2 M HCl elutes were analysed by differential pulse polarography (DPP). The interference of foreign ions has also been studied. Effects of various instrumental parameters are investigated and received conditions are optimized. The total metal concentration of the milk samples in the study area were in the following ranges 0.030–0.090 μg L−1 of Cd(II), 0.009–0.026 μg L−1 of Pb(II) respectively. The limits of detections were found to be 0.020 and 0.024 μg L−1 for Cd(II) and Pb(II) respectively by applying a preconcentration factor ∼40. The proposed enrichment method was applied successfully for the determination of metal ions in cows', goats', ewes', buffalos' and humans' milk samples.
Chemical Oxidative Degradation of Acridine Orange Dye in Aqueous Solution by Fenton's Reagent
Authors: Chen Chiing‐Chang , Wu Ren‐Jang , Tzeng Yi‐You , Lu Chung‐Shin
Published: May 2015

Degradation of acridine orange (AO) in aqueous solution by Fenton's reagent (Fe2+ and H2O2) was investigated. The effects of different reaction parameters such as initial AO concentration, pH value of solution, ferrous concentration, hydrogen peroxide concentration, and the presence of chloride ion on the oxidative degradation of AO were investigated. Under optimum conditions, 2 mM H2O2, 0.4 mM Fe2+ and pH 3.0, the initial 0.2 mM AO solution was reduced by 95.8% within 10 min. The primary intermediates of the degradation reaction of AO were identified. The analytical results indicated that the N‐de‐methylation degradation of AO dye took place in a stepwise manner to yield mono‐, di‐, tri‐, and tetra‐N‐de‐methylated AO species generated during the Fenton process. The probable degradation pathways were proposed and discussed.
A New Diterpenoid and other Constituents from Acanthopanax Brachypus Harms
Authors: Hu Hao‐Bin , Fan Jun
Published: May 2015

Phytochemical investigation of the stem bark of Acanthopanax brachypus afforded a new labdanetype diterpene glycoside, 3α‐trans‐sinapoyloxy‐jhanol 18‐O‐β‐D‐glucopyranoside (1), together with four known compounds, including one diterpene acid, acanthoic acid (2), one coumarin, isofraxidin (3), one phenolic glycoside, sasanquin (4), as well as one chalcone glycoside, okanin 4‐methyl ether‐3′‐O‐β‐D‐glucopyranoside (5). All of the structures were characterized by means of spectroscopic methods, including 1H, 13C, 2D‐NMR and HR‐MS, as well as chemical methods and comparison with the literature data.
Reliable Technique for the Determination of Sodium Dodecyl Sulphate by Crystal Violet in Relation to the Effluents of Durg‐Bhilai Region
Authors: Sar Santosh K. , Verma Chanda , Pandey Piyush K. , Bhui Ashish
Published: May 2015

A simple spectrophotometric method applicable to waste water bodies is developed for the determination of anionic surfactant (AS). An ion‐association complex is formed between an anionic surfactant Sodium dodecyl sulphate (SDS) and a cationic dye Crystal Violet (CV). The dark blue colored complex can be easily extracted in organic solvent benzene. The absorbance of the complex in benzene layer is measured spectrophotometrically at maximum wave length (λ max) of 565 nm. Under the optimal experimental conditions, absorbance of the organic extractant obeyed Beer's law over the range of 0.75–10.00 μg mL−1 of SDS and the LOD was 0.01312 μg L−1. It is noticed that the present method is much easier, less time consuming and applicable to accelerated urbanization and industrial development found in newly formed Chhattisgarh state in Central India.

The validity of the method was tested in regionalized industrial and domestic waste water runoff.
Highly Efficient CuI‐Catalyzed N‐Arylation of Azaheterocycles with Aryl Iodides Using 1,1,1‐Tris(Hydroxymethyl)ethane as a Tridentate O‐Donor Ligand: A Shorter Route to Toloxatone and Formal Synthesis of Linezolid
Authors: Chen Hsin‐Hung , Huang Hua‐Min , Chen Shu‐Chih , Chen Yao‐Jung
Published: May 2015

An efficient copper‐catalyzed N‐arylation of azaheterocycles with aryl iodides using 1,1,1‐tris(hydroxymethyl)ethane as a tridentates O‐donor ligand has been accomplished in good to excellent yields. Moreover, this highly efficient catalyst system has been successfully demonstrated to one‐step synthesis of toloxatone and a shorter route to formal synthesis of linezolid in good yields.
Synthesis of 4‐Aryl‐3‐Methyl‐1‐Phenyl‐1H‐Benzo[h]Pyrazolo[3,4‐b]Quinoline‐5,10‐diones Using Diammonium Hydrogen Phosphate as an Efficient and Versatile Catalyst in Water
Authors: Wu Li‐Qiang , Dong Ruo‐Yi , Yang Chun‐Guang , Yan Fu‐Lin
Published: May 2015

A simple and efficient synthesis of 4‐aryl‐3‐methyl‐1‐phenyl‐1H‐benzo[h]pyrazolo[3,4‐b]quinoline‐5,10‐diones has been accomplished by the one‐pot condensation reaction of 3‐methyl‐1‐phenyl‐1H‐pyrazol‐5‐amine, aldehydes and 2‐hydroxynaphthalene‐1,4‐dione in water in the presence of diammonium hydrogen phosphate.
A Simple and Rapid High Performance Liquid Chromatographic Method with Fluorescence Detection for the Estimation of Amikacin in Plasma ‐ Application to Preclinical Pharmacokinetics
Authors: Chang Xiao‐Juan , Peng Jing‐Dong , Liu Shao‐Pu
Published: May 2015

A simple and sensitive reversed‐phase liquid chromatographic method has been developed for the determination of amikacin by derivatization. The method is based on the pre‐column derivatization of amikacin with 9‐fluorenylmethyl chloroformate (FMOC‐Cl). Isepamicin was used as the internal standard. The derivatization reaction proceeds in aqueous solution at room temperature with a borate buffer of pH 7.3. The formation of the corresponding derivative of amikacin is instantaneous and it is stable for more than 48 h. Detection was performed by fluorescence. Several factors influencing the derivatization reaction yields were studied and optimized. The system offered the following analytical parameters: limit of detection (LOD) of 90 ng mL−1 (3σ), linear correlation coefficient of 0.9998 and linear range response from 0.45 to 21.60 μg‐mL−1. The precision of the method was < 6%. As a preliminary application, the method has been successfully applied to the amikacin determination in parenteral pharmaceutical formulations.
Aggregation Influence of Polyethyleneglycol Organic Solvents with Ionic Liquids BMIBF4 and BMIPF6
Authors: Wu Tzi‐Yi , Wang Hao‐Cheng , Su Shyh‐Gang , Gung Shr‐Tusen , Lin Ming‐Wei , Lin Cheng‐Bo
Published: May 2015

Polyethyleneglycol (PEG, Mw = 200, 300, 400) and polyethyleneimine (PEI, Mw = 423) are used to investigate the ion‐ion interactions in liquids and physicochemical properties after the addition of PEG (or PEI) to ionic liquids 1‐butyl‐3‐methylimidazole tetrafluoroborate (BMIBF4) or 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BMIPF6). Nuclear magnetic resonance is used to investigate the effects of solvent content (x = 0.05, 0.1, 0.2, 0.3, 0.4, 0.5) and temperature (303–338 K) on the diffusion coefficient, chemical shift, and two dimensional NOESY, HOESY spectra. HOESY spectra show that a hydrogen bond forms between the alkyl hydrogen of PEG and the 19F atom of BF4− and PF6−. After the addition of PEG to BMIBF4 (or BMIPF6), the aggregation is the dominant effect for the diffusion coefficient result. When the molecular weight and the concentration of PEG increase, the effect of coving generates larger clusters involving PEG, BMI+ and its counter anion. The BF4− group of the BMIBF4/PEG system is smaller than PF6−, it's easier to generate clusters in the BMIBF4/PEG system than it is in the BMIPF6/PEG system.
Simultaneous Quantitation of Captopril and NSAID's in API, Dosage Formulations and Human Serum by RP‐HPLC
Authors: Sultana Najma , Arayne M. Saeed , Naveed Safila
Published: May 2015

An accurate, sensitive and least time consuming reverse phase high performance liquid chromatographic (RP‐HPLC) method for the estimation of captopril in the presence of non steroidal anti‐inflammatory drugs in formulation and human serum has been developed and validated. Chromatographic separation was conducted on prepacked Purospher star C18 (5 μm, 25 × 0.46 cm) column at room temperature using methanol:water (80:20 v/v) as a mobile phase, pH adjusted at 2.8 with o‐phosphoric acid and at a flow rate of 1.0 mL min−1, while UV detection was performed at 227 nm. The limit of detection and quantification for captopril were 1 and 0.35 ng mL−1, while that for (NSAID's) i.e. flurbiprofen, ibuprofen, diclofenac sodium and mefenamic acid LOD were 0.2, 1, 2 and 0.4 ng mL−1 respectively and LOQ were 0.9, 2.9, 8 and 1 ng mL−1 Analytical recovery was > 98.1%. The method used for the quantitative analysis of commonly administered non steroidal anti‐inflammatory drugs (NSAID's) i.e. ibuprofen, flurbiprofen, diclofenac sodium and mefenamic acid alone or in combination with captopril from API (active pharmaceutical ingredients), dosage formulations and in human serum. The established method is rapid (RT < 12 min), accurate (recovery > 98.1%), selective (no interference of excepients and other commonly used drugs and food) and sensitive (LOQ 3.5 ng mL;‐1) and reproducible (SD ± 0.003).
Study on Separation/Enrichment and Determination of Mercury(II) using Microcrystalline Thymolphthalein Loaded with Ternary Association Complex
Authors: Chang‐Qing Tu , Xin‐Rong Wen
Published: May 2015

The paper presents a novel method for the separation/enrichment of Hg2+ using microcrystalline thymolphthalein loaded with ternary association complex prior to the determination by spectrophotometry. The effects of different parameters, such as the dosages of KI and dodecyl trimethyl ammonium bromide (DTAB) and thymolphthalein, various salts and acidity etc. on the enrichment yield of Hg2+ have been investigated to select the experimental conditions. The results showed that in the presence of 1.0 g NaCl, when the dosage of 0.1 M KI solution was 1.50 mL and 5.0 × 10−3 M dodecyl trimethyl ammonium bromide (DTAB) solution was 1.50 mL respectively, the water‐insoluble ternary association complex of (DTAB)2(HgI4) which produced by Hg2+ and I−, DTAB cation (DTAB+) was quantificationally absorbed on the surface of microcrystalline thymolphthalein Therefore, Hg2+ was separated completely from Zn2+, Mn2+, Ni2+, Co2+, Fe3+, Al3+, Pb2+, Bi3+ and Cr3+ etc. by contolling acidity. The possible enrichment mechanism of Hg2+ was deduced. The proposed method has been successfully applied to the determination of Hg2+ in the sample of industrial waster water, and the results agreed well with the dithizone method. The recoveries were 94.5%∼106.5%, and the RSD was 2.0%∼2.8%.
Electrocatalysis of Hemoglobin in ZnO Nanoparticle/Ionic Liquid Composite Film Modified Glassy Carbon Electrode
Authors: Wang Dan‐Dan , Liu He‐Jian , Zhao Chang‐Zhi , Hui Ni , Sun Wei
Published: May 2015

A nanobiocompatible composite containing hemoglobin (Hb), ZnO nanoparticles (nano‐ZnO) and ionic liquid 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BMIMPF6) was fabricated and further modified on the glassy carbon electrode (GCE). The electrochemical behaviours of Hb in the composite film were carefully studied and a pair of quasi‐reversible redox peaks appeared in pH 7.0 phosphate buffer solution, which was attributed to the electrode reaction of Hb heme Fe(III)/Fe(II) redox couple. The presences of nano‐ZnO and BMIMPF6 in the film can retain the bioactivity of Hb and greatly enhance the direct electron transfer of Hb. The immobilized Hb showed high stability and good electrocatalytic ability to the reduction of hydrogen peroxide and O2.
Determination of Total Iron in Environmental Samples by Solid Phase Extraction with Dimethyl(E)‐2‐(2‐Methoxyphenoxy)‐2‐Butenedioate
Authors: Khayatian Gholamreza , Kolaie Hamidreza Ahmadzadeh Vosta , Nasiri Farough , Atashkar Bahareh , Hassanpoor Shahed
Published: May 2015

A novel solid phase extraction technique for determination of total iron in environmental water samples was developed. The method is based on sorption of Fe(III) ions on octadecyl silica membrane disk modified with a new synthetic ligand dimethyl(E)‐2‐(2‐methoxyphenoxy)‐2‐butenedioate (I). Iron(III) is quantitatively retained on the disk in the pH range of 3–7 at a flow rate of 1–7 mL min−1. The Fe(III) eluted with 10 mL of 0.01 M EDTA and than was measured by flame atomic absorption spectrometry (FAAS) at 248.3 nm. The maximum capacity disk modified by 7 mg of ligand was found to be 197 ± 2 μg of iron(III). The breakthrough volume was greater than 2000 mL. The iron(III) was completely recovered (> 99%) from water with a preconcentration factor of more than 200. The limit of detection of the proposed method was 1.00 ng mL−1. The various cationic and anionic interferences had no effect on the recovery of iron(III) from the binary mixtures. The proposed method was successfully applied to determination of total iron from three different water samples.
Synthesis and Characterization of Achiral Bent‐Core Liquid Crystalline Molecules Containing Salicylaldimine‐Based with a Wide Temperature Range of SmCP Phase
Authors: Liao Chien‐Tung , Liu Jung‐Yo , Zou Sing‐Fang , Wu Nien‐Chieh , Wu Zheng‐Long , Lee Jiunn‐Yih
Published: May 2015

The design and synthesis of a series bent‐core materials base on a 3,4′‐biphenyldiol central core containing salicylaldimine‐based and two terminal tetradecyloxy tails are reported. In addition, the effects of lateral substituents (R = F and Cl) at the biphenyl core into 3′‐position are examined. These substituents have a strong influence in reducing the clearing temperatures and increasing temperature range of SmCP phase. Upon cooling process the isotropic liquid, compound SB‐Cl exhibits the lowest clearing transition temperature of 180°C and the widest SmCP phase range of 129°C. The mesophase behaviour were investigated by polarizing optical microscopy (POM), differential scanning calorimetry (DSC), X‐ray diffraction (XRD), and electro‐optical (EO) measurements in the mesophase temperature range.
Metallopeptides — from Drug Discovery to Catalysis
Authors: Ming Li‐June
Published: May 2015

Oligopeptides are involved in diverse biological activities, including neurotransmission and antibiotic. Many natural‐occurring peptides and peptide‐ketide hybrids exhibit specific biological activities and chemical reactivities upon binding with certain metal ions, such as divalent metal‐binding antibiotic bacitracin and anticancer Fe/Cu‐bleomycin. There are also numerous synthetic peptides designed to bind metal ions to exhibit wide range of physical properties and chemical and biological activities. In this review we summarize the background and discuss our research on metal binding properties, structures, and chemical reactivities of three metallopeptides, the bacterial antibiotic bacitracin, the Alzheimer's disease‐related β‐amyloid, and the salivary antimicrobial histatin. Despite their different structures and biological functions, the Cu2+ complexes of these peptides exhibit significant activities toward catechol oxidation and phenol hydroxylation. However, the mechanisms of the oxidative reactions among these three Cu‐peptides seem to be distinctively different. Our current understanding about the structure‐bioactivity relationship and chemical reactivities as well as implications in drug discovery of these peptides are summarized herein.
A Novel Approach for the Solid‐Phase Organic Synthesis of 1, 3‐Disubstituted Uracils
Authors: Wei Mei‐Hong , Lin Shu‐Ying , Sheng Sheng‐Ri , Wang Qing , Cai Ming‐Zhong
Published: May 2015

A novel procedure for solid‐phase organic synthesis of 1, 3‐disubstituted uracils using a cyclization‐cleavage strategy from Wang‐acrylate resin, amines and isocyanates. An acrylate ester resin is reacted in turn with PhSeBr and primary amines in one‐pot to afford N‐substituted α‐phenylseleno‐β‐aminoesters followed by treatment with isocyanates to form α‐phenylseleno‐β‐ureidoester resin. Following oxidation‐elimination with excess of 30% hydrogen peroxide and intramolecular cyclization cleavage of the Wang resin using potassium ethoxide as a base to furnish 1, 3‐disubstituted uracils in good yields (80‐86%) and high purities (92‐96%).
Synthesis and Characterization of a Novel Benziloxime Ligand and Its Iron(III) and Nickel(II) Complexes
Authors: Soleimani Esmaiel
Published: May 2015

The synthesis of a novel benziloxime ligand, 4,4′‐dibromobenzilmonoxime (DBBOH) (1) and its complexes [Fe(DBBO)3] (2) and Na[Ni(DBBO)3] (3) are described. The ligand (DBBOH) was prepared in MeOH from the reaction of 4,4′‐dibromobenzil with hydroxylamine hydrochloride in the presence of sodium acetate.

Reaction of sodium salt of 4, 4′‐dibromobenzilmonoxime (DBBONa) in MeOH with Fe(NO3)3.9H2O and Ni(NO3)2.6H2O yielded [Fe(DBBO)3](2) as yellow and Na[Ni(DBBO)3] (3) as brown precipitates respectively.

The ligand, 4, 4′‐dibromobenzilmonoxime (DBBOH) (1) and its complexes [Fe(DBBO)3](2) and Na[Ni(DBBO)3] (3) were characterized by elemental analysis, 1H‐NMR and 13C‐NMR, IR, and electronic spectral studies.

The analysis of IR, 1H‐ and 13C‐NMR spectral data of Fe(III) and Ni(II) complexes suggest that 4,4′‐dibromobenzilmonoximate is bonded to iron(III) and nickel(II) ions through the oxygen atom of the carbonyl, and the nitrogen atom of the imine groups. The electronic spectral data of the complexes in CHCl3 are in good agreement with the octahedral coordination of Fe(III) and Ni(II) ions. The ligand field parameters for these complexes, i.e. splitting energy and Racah parameter were calculated to be 21560 cm−1 and 707 cm−1 for [Fe(DBBO)3] (2), 13440 cm−1 and 610 cm−1 for Na[Ni(DBBO)3] (3) respectively.
Dissolution of 3,4,5‐Triamino‐1,2,4‐triazole Dinitramide in N‐Methyl Pyrrolidone
Authors: Xue Liang , Zhao Feng‐Qi , Xing Xiao‐Ling , Zhou Zhi‐Ming , Wang Kai , Gao Hong‐Xu , Yi Jian‐Hua , Hu Rong‐Zu
Published: May 2015

The dissolution properties of 3,4,5‐triamino‐1,2,4‐triazole dinitramide in N‐methyl pyrrolidone (NMP) was measured using a RD496‐2000 Calvet microcalorimeter at four different temperatures under atmospheric pressure. Differential enthalpies (ΔdifH) and molar enthalpies (ΔsolH) were determined for 3,4,5‐triamino‐1,2,4‐triazole dinitramide in NMP. The corresponding kinetic equations that describe the four dissolution processes are \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{{{\rm d\alpha }}}{{{\rm d}t}} = 1.78 \times 10^{ - 4} \left({1 - {\rm \alpha }} \right)^{1.01} \left({T = 298.15{\rm K}} \right) $\end{document}, \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{{{\rm d\alpha }}}{{{\rm d}t}} = 1.96 \times 10^{ - 4} \left({1 - {\rm \alpha }} \right)^{1.06} \left({T = 303.15{\rm K}} \right) $\end{document}, \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{{{\rm d\alpha }}}{{{\rm d}t}} = 2.15 \times 10^{ - 4} \left({1 - {\rm \alpha }} \right)^{0.96} \left({T = 308.15{\rm K}} \right) $\end{document}, \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{{{\rm d\alpha }}}{{{\rm d}t}} = 2.34 \times 10^{ - 4} \left({1 - {\rm \alpha }} \right)^{1.06} \left({T = 313.15{\rm K}} \right) $\end{document} solution of 3,4,5‐triamino‐1,2,4‐triazole dinitramide in NMP, respectively. The values of activation energy E and pre‐exponential factor A for the dissolution process are obtained as 14.13 kJṁmol−1 and 5.34 × 10−2 s−1.
Synthesis and Characterization of Uniform Fine Particles of Nickel Compounds
Authors: Haq Ikram Ul , Haider Farzana
Published: May 2015

Nickel oxalate particles were prepared by mixing aqueous solutions of nickel sulfate and oxalic acid at 25 and 85 °C. Effect of composition of the reacting solutions and pH of the resulting dispersion was evaluated on morphology of the precipitated particles. Besides these parameters, isoelectric point of the nickel oxalate played a major role in the particles build up. On control heating at 340 °C, the nickel oxalate particles converted into nickel oxide particles while preserving their particles' integrity to a maximum extent. Selected batches of the as‐prepared and heat‐treated particles were characterized by various physical methods.
Fast Analysis of Phenolic Acids by Microchip Capillary Electrophoresis with Serpentine Channel and End Wrapped Electrode
Authors: Cheng Hsien‐Yu , Chen Show‐Chuen , Lee Hui‐Ling
Published: May 2015

A microchip capillary electrophoresis with amperometric detection, μCE‐EC, for the analysis of phenolic acids is described. The problem of noise‐laden signal under high electric field was tackled by adopting the end‐channel design of electrode configuration: more specifically with the end‐wrapped electrode configuration. At full stretch of effort, a finely tuned electrode could bring the detection limit well below micro molars for dopamine. At the end of the 10‐cm serpentine micro‐channel, a Pt electrode biased at +0.9 V (vs. Ag/AgCl) served as the working electrode. Injection of gentisic acid, protocatechuic acid, vanillic acid, p‐coumaric acid, caffeic acid, ferulic acid, sinapic acid and chlorogenic acid gave repeatable results: the migration time deviating within 3.80% (n = 7) and peak current between 1.45 and 4.50%. Under the optimized conditions, the detection limits for phenolic acids could be brought down to the range between 1.82 μM and 19.85 μM at S/N = 3. The regression coefficient of the calibration curve over the range between 10 and 800 μM was better than 0.995. The merits of increased efficiency with serpentine channel and improved sensitivity with end‐wrapped electrode are promising. Beer samples were tested for feasibility as a routine tool.
Rapid Identification of the Antioxidant Constituent of Koelreuteria Henryi
Authors: Chen Chin‐Hui , Chen Pi‐Yu , Wang Kuang‐Chuan , Lee Ching‐Kuo
Published: May 2015

In recent years, on‐line coupling of separation and activity determination techniques has been achieved by mixing a free radical solution with the eluate of an HPLC column. Such techniques enable the rapid and selective detection of radical scavenging substances in the sample preparation. This study investigates the antioxidant properties of the leaves of Koelreuteria henryi L. using a microarray reader and HPLC. The antioxidant, 1,3,4,5‐tetra‐O‐galloylquinic acid (1), was first isolated from this plant and estimated using LC‐MS/MS and NMR methods. The scavenger activity of (1) was then determined using 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical and xanthine oxidase (XOD) assays, producing an IC50 of 7.1 μM and 6.7 μM, respectively. Results show that this compound has an excellent antioxidant effect in comparison with quercetin.

This study shows that it is possible to rapidly identify the antioxidant constituents of K. henryi L. using the hyphenated DPPH (or XOD) assays and LC‐MS/MS methods.
QSAR Study on ACE Inhibitors by Using OSC‐PLS Algorithm
Authors: Long Hai‐Xia , Wang Yuan‐Qiang , Lin Yong , Lin Zhi‐Hua
Published: May 2015

A set of descriptors was derived from a matrix of three structural variables of the natural amino acid, including Van Der Waal's volume, net charge index and hydrophobic parameter of side residues. They were selected from many properties of amino acid residues, which were the primary properties to influence the interaction between peptides and its protein receptor. They were then applied to structure characterization and QSAR analysis on agiotensin‐converting enzyme inhibitor di‐peptides by using orthogonal signal correction (OSC) method combined with partial least squares (PLS) method. The results of QSAR analysis on di‐peptides obtained are as following: the cross‐validation correlative coefficient (Q2) was 0.817, and the correlative coefficient (R2) was 0.838, and the root mean‐square (RMS) was 0.410. Test sets of peptides were used to validate the quantitative model, and it was shown that all these QSAR models had good predictability for outside samples. The results showed that, in comparison with the conventional descriptors, this descriptors was a useful structure characterization parameter for peptide QSAR analysis, and also showed that the OSC‐PLS method is better than the traditional PLS method.
A Review on the Emitting Species in Conjugated Polymers for Photo‐ and Electro‐luminescence
Authors: Chen Show‐An , Jen Tzu‐Hao , Lu Hsin‐Hung
Published: May 2015

In conjugated polymers, fluorescence from a single polymer chain, which is contrasted with measurements on an ensemble or bulk collection of molecules, can provide important information about conformation of single polymer chain and energy transfer between different conjugation length segments within single polymer chain. On the other hand, the presence of intrachain or interchain interactions plays an important role on their photoluminescence (PL) and electroluminescence (EL) properties. In addition to non‐interacting isolated chain, there are five interacting emitting species, namely: photo‐excited dimers including excimer and exciplex, electrical‐excited dimers including electromer and electroplex, and aggregate. Excimer, exciplex, and aggregate can lead to a generation of new peak with featureless structure on the longer wavelength side in the fluorescence spectrum and usually cause a lowering in PL quantum efficiency. These three emitting species can be observed in both PL and EL spectra. In addition, electromer and electroplex only appear in EL spectrum but not in PL spectrum. The presence of electromer and electroplex also leads to a new peak at longer wavelength side. Another non‐interacting ground‐state emitting species, β phase, consists of a chain segment with a more coplanar conformation and therefore results in a longer conjugation and clear vibronic transitions.
Blocked Electron Transfer and Suppressed Blinking of Single CdSe/ZnS Quantum Dots in Agarose Gel
Authors: Ko H. C. , Yuan C. T. , Lin S. H. , Tang Jau
Published: May 2015

Fluorescence blinking is an interesting phenomenon commonly observed in single molecule/particle spectroscopy and has attracted wide interest recently. Such behavior in quantum dots is undesirable for applications as fluorescence markers. In this report, we observed suppressed blinking for single CdSe/ZnS quantum dots mixed in agarose gel. We attributed the suppression to an increase in activation energy so that the charge transfer is blocked from the neutral light state to the charged dark state as the gel concentration increases.
Effect of Broken Symmetry on the First Hyperpolarizability of a Centrosymmetric Molecule with an Application to Furan‐Containing [2.2]Cyclophandiene
Authors: Chang Yao‐Wen , Jin Bih‐Yaw
Published: May 2015

The effects of broken symmetry on the first hyperpolarizability for centrosymmetric molecules are studied with the so‐called VB‐4CT model. We show that the first hyperpolarizability can be enhanced dramatically when certain centrosymmetric molecules with intrinsic bistable adiabatic potential surface has its symmetry broken due to the external asymmetric perturbation, albeit this value should vanish when no any asymmetric external field is present. Particularly, we discover that the stiffness of molecular geometry and the susceptibility to weak asymmetric perturbation are related to the extent of charge‐transfer exciton in its electronic ground state. This mechanism is then successfully applied to the exceptionally high first hyperpolarizability of furan‐containing [2.2]cyclophandiene with inversion symmetry by combining the simple VB‐4CT model and quantum chemical calculation.
Applications of Surface‐Functionalized Diamond Nanoparticles for Mass‐Spectrometry‐Based Proteomics
Authors: Wu Chih‐Che , Han Chan‐Chung , Chang Huan‐Cheng
Published: May 2015

Building upon recent success, diamond nanoparticles or nanodiamonds (NDs) for short have emerged as a promising new nanomaterial for biological applications. The material holds several unique properties, such as low chemical reactivity, small particle size, large specific surface area, wide optical transparency range, and facile surface functionalizability, making it a useful substrate for affinity purification mass spectrometry. Experiments have shown that the surface of NDs can be readily modified with diverse functional groups for either covalent or noncovalent conjugation with biomolecules. Additionally, NDs conjugated with bioactive ligands or polymers can be used as high affinity probes for selective extraction and enrichment of molecules of interest for characterization by mass spectrometry. This article summarizes the results of our work in employing surface‐functionalized NDs as a unique solid‐phase extraction and elution platform for pre‐concentration, selective extraction, and purification of targeted biomolecules prior to gel electrophoresis or matrix‐assisted laser desorption/ionization mass spectrometric analysis. Recent progress and future perspectives are discussed.
Synthesis of Novel Polyamine Fluorescence Sensors
Authors: Xi Hai‐Tao , Xiong Min‐Qiu , Wang Lei‐Lei , Hu Quan‐Zi , Sun Xiao‐Qiang
Published: May 2015

A highly selective and efficient method for the synthesis of novel polyamine fluorescence sensors is being offered. Remarkable increase of yields was observed, due to using potassium carbonate as proton trapper. The reaction is fast and easy‐to‐run in favorable conditions which accompanying by fewer side effects.
A Study of Artificial Neural Networks for Electrochemical Data Analysis
Authors: Hsueh Kan‐Lin
Published: May 2015

Artificial neural network has been demonstrated the capability of identifying the chemical composition from various analytical methods. This study tested the feasibility of using a single network to calculate data obtained from polarography, linear scanning voltammetry (LSV), and electrochemical impedance spectroscopy (EIS). Computer generated data were used for network learning and testing. The network property of a single layer network was calculated at various learning cycles, learning rates, and β values of the neuron activation function. This study also evaluated two‐layer, three‐layer, and four‐layer networks. Test results conclude that a single artificial neural network could analyze various analytical data by using corresponding weight matrices. To produce accurate results, the network requires high training cycle, small β value of sigmoid function, and small learning rate. Network accuracy increase as the number of neuron increased to certain extents. Network structure plays minimum effects on the accuracy of network for a given number of neurons.
Novel Complexes of Mn(II), Co(II), and Cu(II) with Ligand Derived from Dibromobenziloxime
Authors: Soleimani Esmaiel
Published: May 2015

The preparation of 4,4′‐dibromobenzilmonoxime (BBOH) (1) and its complexes Na[M(BBO)3] (where M = Mn(II) (2), Co(II) (3), Cu(II) (4)) are described. The ligand (BBOH) was prepared in MeOH from the reaction of 4,4′‐dibromobenzil with hydroxylamine hydrochloride in the presence of sodium acetate.

Reaction of sodium salt of 4,4′‐dibromobenzilmonoxime (BBONa) in MeOH with Mn(CH3COO)2.4H2O, Co(CH3COO)2.4H2O and Cu(CH3COO)2.H2O yielded Na[Mn(BBO)3] (2), Na[Co(BBO)3] (3), and Na[Cu(BBO)3] (4) precipitates respectively.

The analysis of IR, 1H‐ and 13C‐NMR spectral data of Mn(II), Co(II) and Cu(II) complexes suggest that 4,4′‐dibromobenzilmonoximate is bonded to metal(II) ions through the oxygen atom of the carbonyl, and the nitrogen atom of the oxime groups. The electronic spectral data of the complexes in DMSO are in good agreement with the octahedral coordination of M(II) ions.

The splitting energy and Racah parameter were calculated to be 17136 cm−1 and 816 cm−1 for Na[Mn(BBO)3] (2), 15200 cm−1 and 733 cm−1 for Na[Co(DBBO)3] (3) respectively.
QSAR Studies of 3,3′‐(Substituted‐Benzylidene)‐Bis‐4‐Hydroxycoumarin, Potential HIV‐1 Integrase Inhibitor
Authors: Li Bo‐Jian , Chiang Chih‐Chia , Hsu Ling‐Yih
Published: May 2015

A series of biscoumarins against HIV‐1 integrase was subjected to quantitative structure‐activity relationship (QSAR) analysis. The result of the study showed that the inhibitory activity, as determined in the cell culture model, was highly correlated with the electronic (LUMO) and lipophilic effects exhibited by the substitution (R). The relationship can be expressed by the following regression equation: pIC50 = −1.903 (± 1.962) + 0.442 (± 0.066) logP − 4.504 (± 1.788) εLUMO.
Surface Plasmon‐Induced Photoluminescence in Au‐CdSe Hybrid Architectonic Solids
Authors: Chen Wei‐Hung , Ko Wen‐Yin , Fu Shu‐Juan , Zeng Ching‐Hua , Lin Kuan‐Jiuh
Published: May 2015

We have dramatically induced the photoluminescence intensity of CdSe quantum dots emitted from plasma antennas, an intuitive picture consisted of a dense shell of CdSe nanocrystals spontenously deposited onto Au metallic grating nanowires which result from the connection of Au nanocrystals through hydrogen bonding. The Au‐CdSe nanowires exhibit a remarkable red‐shift surface plasmons energy band (77 nm) from 529 to 606 nm with respect to the complex‐like colloids in a methanol solution and induced a narrower solid‐state band‐edge photoluminescence at 625 nm with a peakwidth of 23 nm.
Me3SiOTf Promoted Aza‐Michael Addition Reaction of 1°‐Amides with α,β‐Unsaturated Ketones
Authors: Lee Adam Shih‐Yuan , Lin Mei‐Chun , Lin Chih‐Chen , Chang Yu‐Ting
Published: May 2015

Lewis acid, Me3SiOTf, has been shown to be a promising promoter for aza‐Michael reaction of relatively acidic primary amide with α,β‐unsaturated ketone. A sries of α,β‐unsaturated ketones was transformed to their corresponding β‐amido ketones with moderate yields under this reaction condition.
A Rapid, Solvent‐Free Phase‐Transfer Catalysis Procedure for N‐Alkylation of Dihydropyridones and Construction of the Indolizidine, Quinolizidine and Pyridoazepine Structures
Authors: Chou Shang‐Shing P. , Liu Chih‐Fen
Published: May 2015

We have developed a solvent‐free phase‐transfer catalysis (PTC) method for the N‐alkylation of sulfur‐substituted dihydropyridone 4a to give products 5 with varying side‐chains and functional groups. Treatment of the chlorides 5a and 5c with NaI in acetone at reflux gave high yields of the iodides 6a and 6b. The reaction of iodides 7a and 7b with t‐BuLi at low temperature, followed by sequential treatment with HOAc and NaBH4, resulted in the formation of quinolizidine 8a and pyridoazepine 8b, respectively. Similar reaction of bromide 5j with t‐BuLi gave indolizidine 11.
Reduction of N‐acetyl Aspartate in Bilateral Cerebral Tissue in Relation to Compromised Cerebrovascular Reserve Capacity as Investigated by Proton MR Spectroscopy and Acetazolamide Test
Authors: Lee Chang‐Shin , Chen Cheng‐Yu
Published: May 2015

Patients with a symptomatic occlusion of the internal carotid artery or middle cerebral artery are at risk of future stroke. The magnetic resonance spectroscopy (MRS) study in such patients has shown no evidence of the reduced N‐acetyl aspartate (NAA) in regions ipsilateral to a carotid stenosis or occlusion. This result may be partially attributed to the location of MRS voxel in areas without the reduced perfusion reserve. We hypothesize that it is possible to observe the abnormal metabolism if MRS voxel can be placed in areas with the reduced cerebrovascular reserve. Perfusion measurements may allow the assessment of cerebral perfusion reserve by challenge such patients with cerebral vasodilation drugs such as acetazolamide. 38 patients with chronic occlusion or severe stenosis of the internal carotid artery or middle cerebral artery with or without infarction have been performed with challenge test and MRS studies. In addition, 12 normal volunteers were performed with MRS but without challenge test. Perfusion reserve was evaluated by ΔrCBF% and post‐challenge mean transient time (MTT). A correlation was observed between ΔrCBF% and post‐challenge MTT (r = −0.67). Patients without acute infarction were divided into two groups as mild and severe, compromised in according to the post‐challenge hemodynamic data. The spectra for analysis were recorded from voxels in bilateral temporo‐parietal white matter area without MRI visible infarction. Metabolite concentration was normalized to the concentration of creatine (Cr). Between normal and severe group, the NAA/Cr ratios in bilateral cerebral tissue were shown to be significantly differences, so do those between mild and severe group (p < 0.01). In this work, we demonstrated that abnormal metabolism can be detected by MRS method. NAA/Cr ratio may also be reduced in the unaffected contralateral brain. A threshold level of NAA/Cr was shown to be sustainable until the irreversible ischemic ictus occurs.
Pharmacophore Modeling of Tyrosine Kinase Inhibitors: 4‐Anilinoquinazoline Derivatives
Authors: Chang Yeong‐Sheng , Wang Bo‐Cheng , Yang Ling‐Ling
Published: May 2015

A pharmacophore model for the inhibition of Tyrosine Kinase is established that could serve as a guide for the rational design of high potent and selective inhibitors. Recently, quantitative structure‐activity relationships for 4‐anilinoquinazoline class of inhibitors to inhibit EGFR autophosphorylation are in great demand. We have developed a quantitatively predictive chemical function‐based pharmacophore model by using Discovery Studio 2.1 software. The optimal hypothesis consists of four features: three hydrophobic (HYD), and one hydrogen bond donor (HBD) functions. The input for HypoGen was a training set of 16 compounds exhibiting IC50 values ranging between 0.025 nM and 12000 nM, and having the output borne significant conventional coefficient of 0.97. To further validate our design rationale, protein‐ligand docking software was used to elucidate the intra‐molecular interactions. Therefore, the established pharmacophore model could help to a better understanding on how the substituents might influence the activity and afford important information for both ligand‐based and structure‐based drug designs.