bluuebunny/crossref_metadata_2025_split huggingface dataset:
Self‐Assembly and Structure of Cobalt(II) Complexes Using Diaminodiamide Ligands
Authors: Chao Min‐Shiun , Lu Horng‐Hwa , Tsai Ming‐Liao , Hsieh Tsung‐Hsuan , Lin Chien‐Min 
Published: May 2015

AbstractThe self‐assembly of Co(II) with two diaminodiamide ligands, 4,7‐diazadecanediamide and 4,8‐diazaundecanediamide, gave two different crystals, [(C8H18N4O2)Co(OH)2Co(C8H18N4O2)]Cl2 (1) [Co(C9H20N4O2)(Cl)(H2O)]·Cl·2H2O (2). Structures of 1 and 2 were characterized by single‐crystal X‐ray diffraction analysis. Structural data for 1 shows a novel type of binuclear complex with distorted octahederal coordination geometry around the Co atoms through the hydroxo bridges. By using inter‐connector N‐H···N hydrogen bonding interactions as building forces, each cationic moiety [(C8H18N4O2)Co(OH)2Co(C8H18N4O2)]2+ is linked to neighboring ones, producing a charged hydrogen‐bonded 1D chain‐like structure. The chains are further connected into a 2D layer in a (4,4)‐topology via N‐H···Clfree hydrogen‐bonding interactions. Structural data for 2 indicate that the cobalt atom adopts a six‐coordinated N2O4 environment, giving a distorted octahedral geometry, where two N‐ and two O‐donor sets of ligand located at equatorial positions and one water and one chloride occupied at axial positions. Through NH···Cl‐Co and OH···Cl‐Co contacts, each cationic moiety [Co(C9H20N4O2)(Cl)(H2O)]+ in 2 is linked to neighboring ones, producing a charged hydrogen‐bonded 1D chainlike structure. Thus, the crystal‐engineering approach has proved successful in the solid‐state packing due to steric strain effect of the diaminodiamide ligand.
Paclitaxel‐Loaded Stabilizer‐Free Poly(D,L‐lactide‐co‐glycolide) Nanoparticles Conjugated with Quantum Dots for Reversion of Anti‐Cancer Drug Resistance and Cancer Cellular Imaging
Authors: Kuo Wen‐Shuo , Ku Yu‐Cian , Sei Hei‐Tin , Cheng Fong‐Yu , Yeh Chen‐Sheng 
Published: May 2015

AbstractWe prepared the PLGA‐loaded anti‐cancer drug and coated it with quantum dots to make it a dual‐function nanoparticles, and analyzed its potential use in cellular imaging and curing cancers. Two cancer cell lines, paclitaxel‐sensitive KB and paclitaxel‐resistant KB paclitaxel‐50 cervical carcinoma cells, were the relativistic models for analysis of the cytotoxicity of free paclitaxel and paclitaxel‐loaded PLGA conjugated with quantum‐dot nanoparticles. The paclitaxel‐loaded PLGA conjugated with quantum dots nanoparticles were significantly more cytotoxic than the free paclitaxel drug in paclitaxel‐resistant KB paclitaxel‐50 cells. This might have been because the cancer cells developed multi‐drug resistance (MDR), which hampered the action of free paclitaxel by pumping its molecules to extracellular areas. Addition of verapamil, a P‐glycoprotein inhibitor, reversed the MDR mechanism and significantly reduced KB paclitaxel‐50 cell viability. As a result, KB paclitaxel‐50 was highly associated with MDR on the cell membrane. The cytotoxicity results indicated that PLGA nanoparticles served as drug carriers and protected the drugs from MDR‐accelerated efflux. Combined quantum dots with PLGA nanoparticles allowed additional functionality for cellular imaging.
Sonophysically‐Exfoliated Individual Multi‐Walled Carbon Nanotubes in Water Solution
Authors: Su Jun‐Wei , Hsu Chuen‐Yuan , Fu Shu‐Juan , Guo Chian‐Hua , Lin Kuan‐Jiuh 
Published: May 2015

AbstractWe report the sonophysically‐exfoliated methods access to the preparation of homogeneous‐free multi‐walled carbon nanotubes (MWCNTs) in water solution. Highly stable, uniform, individual MWCNTs are entirely performed through sodium dodecylsulfate surfactants by means of a tip sinicator. HRTEM images show that the crystalline finger walls of individual CNTs are apparently observed. Raman spectrum of MWCNTs shows that the so‐called G'‐band, associated with metallic electronic structure, was significantly observed at 2644 cm−1 with full‐width at half‐maximum of 262 cm−1, indicating that the sonication physical methods do not alter their electric properties. Owing to its easy‐to‐use procedure and low cost of implementation, this approach could lead to the commercial viability of the large‐scale MWCNTs processing.
Stabilizer‐Free Poly(lactide‐co‐glycolide) Nanoparticles Conjugated with Quantum Dots as a Potential Carrier Applied in Human Mesenchymal Stem Cells
Authors: Kuo Wen‐Shuo , Hwang Shiaw‐Min , Sei Hei‐Tin , Ku Yu‐Cian , Hsu Lee‐Feng , Cheng Fong‐Yu , Hsieh Patrick Ching‐Ho , Yeh Chen‐Sheng 
Published: May 2015

AbstractWe report that human mesenchymal stem cells (hMSCs) were successfully labeled with poly(lactide‐co‐glycolide) nanoparticles (PLGA NPs) surface‐conjugated quantum dots (QDs) (PLGA‐QD NPs) via endocytosis pathway. These NPs were not toxicity even treated with PLGA‐QD NPs at high concentrations for at least four weeks. Besides, PLGA‐QD NPs‐labeled hMSCs did not change their proliferation and differentiation capability toward the cell fates of adipocytes, osteocytes, and chrondrocytes. It's known that PLGA has been widely employed to act as delivery carrier which encapsulates drugs and releases them under a controlled way. Currently, we have also demonstrated that FITC‐loaded PLGA‐QD NPs degraded in hMSCs to achieve intracellular release of FITC. The aim of this research is to investigate viability, proliferation and differentiation capability and the potential for gene delivery of MSCs labeled with PLGA‐QD NPs. In addition to PLGA‐QD NPs, QDs alone were used to serve as a control set for comparison.
Solid Phase Extraction of Lead(II) by Sorption on Grinded Eucalyptus Stem and Determination with Flame Atomic Absorption Spectrometry
Authors: Mousavi Hassan Zavvar , Aibaghi‐Esfahani Behzad , Arjmandi Azadeh 
Published: May 2015

AbstractA sensitive and simple solid‐phase preconcentration procedure for the determination of trace amount of lead by flame atomic absorption spectrometry (FAAS) is developed. The method is based on the adsorption of Pb2+ on the column of fine grinded eucalyptus stem adsorbent, elution of the column by nitric acid and subsequent determination by FAAS. The effect of different variables such as pH, eluent type, flow rate and interfering ions on the recovery of the analyte was investigated and optimum conditions were established. The adsorption of lead onto fine grinded eucalyptus stem can formally be described by a Langmuir equation with a maximum adsorption capacity of 4.49 mg g−1. A preconcentration factor of 50 was achieved using the optimum conditions. The calibration graph was linear in the range 10–125 ng mL−1 of lead in the initial solution with r = 0.9982. The limit of detection based on 3Sb criterion was 4.5 ng mL−1 and the relative standard deviation for eight replicate measurements of 30 and 80 ng mL−1 of iron was 3.6 and 2.8%, respectively. The method was successfully applied to the determination of lead added to well, tap and wastewater samples.
Layered Zirconium(IV) Aminoethylphosphonate Intercalated with Horseradish Peroxidase for an Amperometric Biosensor
Authors: Liu Chang‐Hua , Guo Xiao‐Li , Yuan Ruo 
Published: May 2015

AbstractLayered zirconium(IV) aminoethylphosphonate (ZrAEP) have been used as matrices for immobilization of horseradish peroxidase (HRP) to fabricate enzyme electrode for an amperometric biosensor. The biocompatible HRP–ZrAEP films were fabricated on gold electrode surface by electro‐co‐deposition method. The morphology of the HRP–ZrAEP composite was characterized by scanning electron microscopy (SEM). UV–vis spectroscopy indicated that the intercalated HRP retained its native structure after incorporation in the ZrAEP. The immobilized HRP at the HRP–ZrAEP films exhibited good electro catalytic responses to the reduction of hydrogen peroxide. The response time of the biosensor was less than 3 s, and the linear range is from 2.5 × 10−6 to 3.22 × 10−3 M, with a detection limit of 7.0 × 10−7 M (S/N = 3). The Michaelis–Menten constant (KappM) value is estimated to be 2.21 mM. In addition, the obtained biosensor possesses high sensitivity, good stability and reproducibility.
Study on Synthesis, Characteristics and Catalysis Properties of Novel Chiral Metal Complexes Catalysts for 1,3‐Dipolar Cycloaddition Reactions of Nitrone with Electron‐Rich Alkene
Authors: You Jun , Liu Bo , Wang Yi 
Published: May 2015

AbstractAs a new class of potential catalysts for 1,3‐dipolar cycloaddition reactions, fourteen L‐amino acid Schiff base Cu(II) and Ti(IV) complexes were synthesized, characterized, and evaluated for their catalytic activities in the reaction between C,N‐diphenylnitrone and electron‐rich ethyl vinyl ether under both homogeneous and in situ conditions. The methods for preparation and utilization of the catalysts were elucidated in detail, and the results of the catalytic reactions were described and discussed as well. Excellent reaction results were found in the presence of some catalysts (20 mol%) with > 90% endo‐isoazolidines produced, compared with predominantly exo‐isoazolidine produced without a catalyst. In addition, the reaction rate is found to be enhanced remarkably by a Cu(II) complex Schiff base catalyst at room temperature.
Can be Azo Dyes Obtained by Grinding under Solvent‐Free Conditions?
Authors: Noroozi‐Pesyan Nader , Khalafy Jabbar , Malekpoor Zahra 
Published: May 2015

AbstractThe solid‐solid reactions of some electron‐donors with sulfanilic acid in the presence of solid sodium nitrite afford azo dyes by self‐catalyzed diazotization of sulfanilic acid (2) under solvent‐free conditions with moderate yields. Also the reactions of some electron‐donors with diazotization of o‐nitroaniline (5), m‐nitroaniline (6) and p‐nitroaniline (7) in the presence of solid sodium nitrite catalyzed by p‐toluenesulfonic acid (PTSA) afford azo dyes under solvent‐free conditions in good yields. This new method totally avoids the use of acids, alkalies, and toxic and/or expensive solvents in diazotization and diazo coupling reactions.
Synthesis and Application of Some Alkali‐Clearable Azo Disperse Dyes Based on Naphthalimide Derivatives
Authors: Parvizi P. , Khosravi A. , Moradian S. , Gharanjig K. 
Published: May 2015

AbstractA series of naphthalimide‐based alkali‐clearable azo disperse dyes containing a fluorosulfonyl group was synthesized. 4‐Fluorosulfonylaniline, 4‐fluorosulfonyl‐2‐nitroaniline and 6‐chloro‐4‐fluorosulfonyl‐2‐nitroaniline as the diazo components were prepared from N‐acetylsulfanilyl chloride and were subsequently coupled with 4‐hydroxy‐N‐3‐methoxypropyl‐1, 8‐naphthalimide. The synthesized dyes and their intermediates were characterized by the use of DSC, FTIR, 1H NMR, 13C NMR, Mass spectroscopy and UV‐visible spectroscopic techniques. Spectrophotometric investigations of prepared dyes in different solvents were carried out in order to obtain their absorption maxima, molar extinction coefficients and solvatochromic effects. The obtained dyes were applied to polyester fabric by the HT method and exhibited good leveling, wash and sublimation fastnesses and moderate light fastness. The synthesized dyes showed that incorporated fluorosulfonyl group to these dyes can be converted to the dyes containing a water soluble sulfonate group in the relatively mild alkaline conditions.
(1,3‐Diphenyl‐1H‐Pyrazol‐4‐yl)‐Methylamine Analogues as Inhibitors of Dipeptidyl Peptidases
Authors: Hsu Tsu , Chen Chiung‐Tong , Tsai Ting‐Yueh , Cheng Jai‐Hong , Wu Su‐Ying , Chang Chung‐Nien , Chien Chia‐Hui , Yeh Kai‐Chia , Huang Yu‐Wen , Huang Chen‐Lung , Huang Chung‐Yu , Wu Ssu‐Hui , Chiang Yi‐Kun , Wang Min‐Hsien , Chao Yu‐Sheng , Chen Xin , Jiaang Weir‐Torn 
Published: May 2015

AbstractA number of pyrazole compounds reported in literatures elicit anti‐hyperglycemic effects. By modifying the side chain of the heterocyclic skeleton, a new chemical class of DPP‐IV inhibitors structurally derived from the (pyrazol‐4‐yl)‐methylamine scaffold have been discovered and evaluated the biological activities of these inhibitors against DPP‐IV, DPP8, DPP‐II and FAP. The SAR studies showed the (1,3‐diphenyl‐1H‐pyrazol‐4‐yl)‐methylamines with 2,4‐dichloro substituents at the 3‐phenyl ring selectively preferred as DPP‐IV inhibitors, whereas with difluoro substituents at the 3‐phenyl ring selectively preferred as DPP8 inhibitors. The binding mode of representative compound 15h at the active site of DPP‐IV was predicted by computer model. In additional, 15h exhibited the ability to significantly decrease the glucose excursion in mice.
Improved Preparation of 3,3′,4,4′‐Tetramethyldiphenylethane by Self Coupling Reaciton in Aqueous Media
Authors: Hu Yu‐Lin , Lu Ming , Liu Qi‐Fa , Ge Qiang 
Published: May 2015

AbstractIn this article, 3,3′,4,4′‐tetramethyldiphenylethane was obtained in 86.5% total yield by self coupling reaction of 3,4‐dimethylbenzyl chloride catalyzed by Cu/Cu2Cl2/PEG‐600 and promoted by iron in aqueous media and the starting material 3,4‐dimethylbenzyl chloride was prepared by chloromethylation of o‐xylene in CTAB micellar catalytic system. Compared to other synthetic methods, the improved method not only enhanced the yield, but also made the operating units easy workup. The mechanisms of the chloromethylation and the self coupling were proposed. The structures of the products were confirmed by Elemental analysis,1H NMR and13C NMR or compared with authentic samples.
Ultrasound Assisted Synthesis of Coumarin Thioglycopyranoside Derivatives
Authors: Yu Lei , Gao Jian‐Fang , Cao Ling‐Hua 
Published: May 2015

AbstractThe methyl coumarins reacted with N‐bromo‐succinimide gave compounds (a∼c) which on further reacted with various peracetyl sulfhydryl glycose (1∼3) afforded a series of novel coumarin thioglycopyranoside compounds (1a∼1c, 2a∼2c, 3a∼3c). And when used ultrasonic irradiation, this method offered several advantages such as good yields and short reaction time than the silent reaction. All the new compounds were characterized on the basis of the IR, 1H NMR, 13C NMR and elemental analysis.
Facile Access to Benzothiazole‐Containing Pyrrolo[1,2‐a]quinolines and Pyrrolo[2,1‐a]isoquinolines via Nitrogen Ylides
Authors: Dawood Kamal M. , Ragab Eman A. , Khedr Nabila A. 
Published: May 2015

AbstractQuinoline and isoquinoline react with 2‐(bromoacetyl)benzothiazole (1) in dry benzene to give the corresponding quinolinium and isoquinolinium salts 2 and 10 which undergo base‐mediated [3+2] 1,3‐dipolar cycloaddition with some acetylene and ethylene derivatives to give the corresponding benzothiazole‐containing pyrrolo[1,2‐a]quinoline and pyrrolo[2,1‐a]isoquinoline derivatives.
Efficient and Convenient Oxidation of Organic Halides to Aldehydes and Ketones Catalyzed by H5IO6/V2O5 in Ionic Liquid [bmpy][PF6]
Authors: Hu Yu‐Lin , Liu Xiang , Lu Ming , Jiang Hui 
Published: May 2015

AbstractA mild, efficient, and eco‐friendly procedure for the oxidation of organic halides to aldehydes and ketones in good to high yields catalyzed by H5IO6/V2O5 in ionic liquid [bmpy][PF6] with no trace of overoxidation to carboxylic acids has been developed. The product can be isolated by a simple extraction with organic solvent, and the catalytic system can be recycled or reused without any significant loss of catalytic activity.
Study of Spectrophotometric Method for Determination of Trace Copper after Separation/Enrichment using Microcrystalline Absorption System
Authors: Tu Chang‐Qing , Wen And Xin‐Rong 
Published: May 2015

AbstractThe paper presents a novel method for the separation/enrichment of copper using microcrystalline absorption system prior to the determination of trace copper by spectrophotometry. The effects of different parameters, such as the dosages of KI and cetyltrimethyl ammonium chloride (CTMAC), various salts and acidity etc on the enrichment yield of Cu2+ have been investigated to select the experimental conditions. The possible enrichment mechanism of Cu2+ was discussed. The results showed that under the optimum conditions, cetyltrimethyl ammonium chloride cation (CTMAC+) reacted with I− to produce the microcrystalline matter (Ms‐M) of (CTMAC+ṁI−), Cu2+ in the solution was absorbed on the surface of Ms‐M of (CTMAC+ṁI−) and reacted with I− to form the precipitation of CuI, Cu2+ was completed enriched on the Ms‐M of (CTMAC+ṁI−). Thereby Cu2+ was separated completely from K+, Na+, Ca2+, Mg2+, Zn2+, Ni2+, Co2+, Mn2+, Fe2+ and Al3+ at pH 4.0. A new method of determination of trace copper was established. The proposed method has been successfully applied to the determination of trace Cu2+ in the sample of human hair, and the results agreed well with AAS method. The recoveries were 94.5% ∼ 105.6%, and the RSD was 2.2% ∼ 2.5%.
Simultaneous Determination of Captopril and Statins in API, Pharmaceutical Formulations and in Human Serum by RP‐HPLC
Authors: Sultana Najma , Arayne M. Saeed , Naveed Safila 
Published: May 2015

AbstractCo‐administration of statins with angiotensin converting enzyme inhibitors is most common, since there is strong synergy between hypertension and hypercholesterolemia in terms of risk factors for the development of cardiovascular diseases. Rapid liquid chromatographic procedure proposed for analysis of captopril and statins in pharmaceutical preparations and human serum using acetonitrile:water (60:40 v/v) as a mobile phase, adjusting pH to 2.9 with UV detection at 230 nm. The advantages of this method include good and rapid separation, well resolved peaks, and only a small amount of sample is required for assay and adequate precision. The method showed good linearity in the range of 2.5‐100 μgmL−1 for captopril and 0.625‐25 μgmL−1 for statins with a correlation coefficient of 0.9999. The recovery of captopril and statins (rosuvastatin, atorvastatin and simvastatin) was > 99.9% and > 99.3%, respectively. The proposed method may be used for the quantitative analysis of captopril and statins alone or in combination in bulk drugs, dosage formulations and in human serum.
Thermal Study in Solid State of Zn(II)‐Diclofenac Complex: Behavior Kinetic of the Dehydration, Transition Phase and Thermal Decomposition
Authors: Kobelnik Marcelo , Quarcioni Valdecir Ângelo , Ribeiro Clóvis Augusto , Capela Jorge Manuel Vieira , Dias Diogenes Dos Santos , Crespi Marisa Spirandeli 
Published: May 2015

AbstractThe dehydration, thermal decomposition and transition phase stage of Zn(II)‐diclofenac compound were studied by simultaneous TG‐DTA and DSC techniques. The TG and DSC curves of this compound were obtained with the mass of sample of 2 and 5 mg. Additionally, DSC curves were carried out in opened and closed α‐alumina pans under static and nitrogen atmosphere. The DTA and DSC curves show that this compound possesses exothermic transition phase between 170‐180 °C, which it is irreversible (monotropic reaction). The kinetics study of this transition phase stage was evaluated by DSC under non‐isothermal conditions. The obtained data were evaluated with the isoconversional method, where the values of activation energy (Ea / kJ mol−1) was plotted in function of the conversion degree (α). The results show that due to mass sample, different activation energies were obtained. From these curves a tendency can be seen where the plots maintain the same profile for closed lids and almost run parallel to each other.
Electrochemical Characteristics of a Copper Hexacyanoferrate (CuHCNF) Modified Composite Carbon Electrode and Its Application toward Sulfite Oxidation
Authors: Majidi Mir Reza , Asadpour‐Zeynali Karim , Shahmoradi Keyvan , Shivaeefar Yadollah 
Published: May 2015

AbstractThe sol‐gel technique was used to construct copper hexacyanoferrate (CuHCNF) modified composite ceramic carbon electrodes (CCEs). The modified CCE was prepared manually by carefully mixing the dispersed graphite powder with Cu powder. Copper hexacyanoferrate (CuHCNF) film has been deposited on the surface of CCE by a simple electroless dipping into a potassium hexacyanoferrate solution method. The cyclic voltammograms of the resulting surface modified CCE under optimum conditions show a well‐defined redox couple due to the K2CuII [FeIII/II(CN)6] system. The electrochemical properties and stability of the modified electrode were investigated by cyclic voltammetry. The effect of different alkali metal cations in the supporting electrolyte on the behavior of the modified electrode was studied and the transfer coefficient (α) and charge transfer rate constant (ks) for the electron transfer between the electrode and modifier layer were calculated. The experimental results show that the peak potential and peak current vary with different alkali metal cations. An extensive study showed that the response of the modified electrode is not affected within a pH range of 2‐8. The modified electrode was used for electrocatalytic determination of sulfite in hard sugar sample.
Study on the Thermochemical and Kinetic Characteristics of Alkali Treated Rice Husk
Authors: Markovska I. G. , Bogdanov B. , Nedelchev N. M. , Gurova K. M. , Zagorcheva M. H. , Lyubchev L. A. 
Published: May 2015

AbstractThe effective utilization of waste rice husk requires detailed studies on the kinetics and mechanism of their thermal and chemical treatment. The present work is a comparative study on the thermo‐chemical and kinetic characteristics of thermal degradation of raw and treated with NaOH rice husk. The optimal conditions for extraction of SiO2 from rice husk in the form of Na2SiO3 were determined using thermal analysis (TA), scanning electron microscope (SEM) and elemental analysis. The experiments were carried out under conditions of non‐isothermal heating in air and nitrogen atmosphere. Using different kinetic models, the values of the effective kinetic parameters, characterizing the destruction process were determined.
Simultaneous Determination of Hesperidin, Ferulic Acid, Cinnamic Acid and Cinnamaldehyde in Chinese Tonic Wine by High Performance Liquid Chromatography
Authors: Lin Iung‐Jr , Cham Thau‐Ming , Wu Shou‐Mei 
Published: May 2015

AbstractThis study aims to establish a HPLC method for the simultaneous determination of hesperidin (HE), ferulic acid (FA), cinnamic acid (CA) and cinnamaldehyde (CAD) in a Chinese tonic wine, Ma‐Zu‐Wan‐Show‐Yao‐Jyo. After filtering the tonic wine, the filtrate was separated on a C18 column (250 × 4.6 mm, 5 μm) by gradient elution of acetonitrile‐aqueous solution. The regression equations were linear (r ≥ 0.9999) in the range of 1.5‐150.0 μg/mL for HE, 0.3‐60.0 μg/mL for FA, 0.06‐6.0 μg/mL for CA, and 0.1‐80.0 μg/mL for CAD. The relative standard deviation and relative error were less than 5.0% and 4.0%, respectively, for intra‐ and inter‐day analyses. The limits of detection (LOD) were 0.6, 0.075, 0.012 and 0.02 μg/mL for HE, FA, CA and CAD (S/N = 3, 20 μ1 injection) respectively. This method can be used to standardize the quality control of Chinese tonic wine to ensure accuracy and efficiency in the future.
A New Farnesene Derivative and Other Constituents from Senecio Cannabifolius
Authors: Xie Wei‐Dong , Weng Cheng‐Wu , Gao Xue , Zhao Hong , Row Kyung‐Ho 
Published: May 2015

AbstractAnew farnesene derivative, 7R*,10S*‐epoxy‐3E,5E‐farnesadien‐1,2,11‐triol, along with eight known compounds was isolated from the aerial parts of Senecio cannabifolius. Their structures were established on the basis of spectroscopic methods.