bluuebunny/crossref_metadata_2025 huggingface dataset:
Development characteristics and hydrocarbon accumulation significance of fractures in Lower Silurian Kalpintag Formation, northern slope of central Tarim Basin
Authors: Hui Guo , Zhongyuan Ma , Li Zhang , Wei Huang , Suju Yang
Published: May 2015

Based on the data of core, microscope thin section, scanning electron microscope, cathode luminescence, and conventional and dipole acoustic logging, the development characteristics and hydrocarbon accumulation significance of fractures in the Lower Silurian Kalpintag Formation on the northern slope of the central Tarim Basin were studied. A large number of mainly high-angle or vertical fractures developed in the study area. They feature low density, long length, medium width and low filling extent. More fractures were found in the relatively weak bands of rock, such as the margins and interlayers of boulder clays. Conventional logging curves showed two peaks and one order of magnitude difference. The anisotropy of fast shear wave in dipole acoustic logging showed that fracture development was influenced by NE trending strike-slip faults and the NE-SW trending maximum horizontal principal stress. The fractures in the Kalpintag Formation played important roles in the formation of tight sand-stone reservoirs. They improved the porosity and permeability of tight sandstones, and the large-scale, high-angle or vertical fractures served as pathways for vertical migration of hydrocarbons. For the small-scale adjustment of hydrocarbon migration, the small-scale, low-angle or horizontal fractures were important.
Pap smears in eldery women look
Authors: Silva Luípa Michele , Coutinho Nychela Junaan Marques , Santos Elita Rozendo do Nascimento , Moreira Júlia Solange Dantas , Piagge Carmem Silvia Laureano Dalle , Silva Antonia Oliveira
Published: May 2015

Objetivo: conhecer as representações sociais de mulheres idosas sobre o exame Papanicolau. Método: pesquisa exploratória de abordagem qualitativa, realizada com 30 idosas atendidas na Unidade de Saúde da Família Maria de Nazaré do município de João Pessoa/PB. Os dados foram analisados com o auxilio do software Alceste. Resultados: análise realizada pelo Alceste apontou seis classes ou categorias, contemplando tanto negativos quanto positivos associados ao referido exame, como: imagens associadas ao exame; posicionamento das idosas frente ao exame; indicações do exame; realização do exame; crenças sobre o exame e justificativas para não adesão. Conclusão: conhecer as representações sociais sobre o exame Papanicolau para idosas possibilita se oferecer ações educativas de saúde que procure minimizar barreiras socioculturais dessas idosas, para uma maior adesão da mulher ao exame preventivo considerando o contexto social e suas vivencias.
Hiv prevention in the school context: what we have and what we want
Authors: Almeida Sandra Aparecida de , Nogueira Jordana de Almeida , Trigueiro Débora Raquel Soares Guedes , Barrêto Anne Jacqueline Roque , Silva Daiane Medeiros da , Silva Luipa Michele
Published: May 2015

Objetivos: identificar os conteúdos relativos à sexualidade que vem sendo trabalhados no ambiente escolar e analisar a compreensão de escolares quanto ao modo de transmissão e prevenção ao HIV/Aids. Método: estudo descritivo, tipo inquérito, realizado com 54 alunos do nono ano do segundo segmento do ensino fundamental de duas escolas municipais de João Pessoa- PB. Dados analisados no Software Statistica 9.0 da Statsoft. Resultados: Na Escola A, privilegiou-se aspectos relacionados à higiene do corpo (44,0%). Na Escola B, evidenciou-se prevenção de doenças sexualmente transmissíveis (58,6%), infecção pelo HIV/Aids (51,7%) e  uso de preservativo(44,8%). Conclusão: A informação direcionada ao cuidado de si deve extrapolar os limites preventivistas e higienistas, incorporando metodologias extensivas, inclusivas e reflexivas, que favoreçam a experiência para uma sexualidade profícua e consequente redução da vulnerabilidade ao HIV/Aids.
Community impact of integrative therapy for renal patients people during session hemodialysis
Authors: Melo Simoni Paula de , Ribeiro Rosa Lúcia Rocha , Costa Aldenan Lima Ribeiro Corrêa da , Urel Denner Regis
Published: May 2015

Objetivo: Compreender as repercussões da Terapia Comunitária Integrativa (TCI) nas pessoas doentes renais durante sessão de hemodiálise. Método: Pesquisa de campo do tipo intervenção, com objetivos exploratórios e descritivos, obtidos na abordagem qualitativa. A TCI foi realizada em julho de 2011, com pessoas renais crônicos, que faziam hemodiálise das 18 às 22 horas. A roda foi gravada, filmada e transcrita. O vídeo foi apresentado aos participantes que, em seguida, foram entrevistados. A transcrição da roda, e as entrevistas foram submetidas à análise temática. Resultados: Percebe-se que a roda provocou uma explosão de sentimentos: emoção, admiração e compaixão, no semblante das pessoas que, de angustiados/entristecidos, passaram a serenos e alegres à medida que a roda foi se desenvolvendo. Conclusão: A TCI foi uma prática para o cuidado, por fornecer a oportunidade de expressar sentimentos, promover reflexão sobre a vivência, condição, tratamento e fortalecimento para enfrentamento de suas dificuldades. Descritores: Terapia, Comunidade, Hemodiálise, Enfermagem.
Nursing care postpartum women seropositive for hiv before the inability to natural breastfeeding
Authors: Costa Aline Mello Salvaya da , Vieira Bianca Dargam Gomes , Alves Valdecyr Herdy , Rodrigues Diego Pereira , Leão Diva Cristina Morett Romano , Pereira Audrey Vidal
Published: May 2015

Objetivos: conhecer a experiência do enfermeiro no cuidado às puérperas soropositivas para o HIV a respeito da amamentação; identificar a interação do enfermeiro com as mulheres com HIV a respeito da impossibilidade de amamentação. Métodos: trata-se de uma pesquisa descritiva, exploratória, de natureza qualitativa, com sete enfermeiros atuantes no alojamento conjunto do Hospital Universitário Antônio Pedro (HUAP) mediante entrevista semiestruturada e analisado com os preceitos da análise de conteúdo na modalidade temática, após aprovação pelo Comitê de Ética do HUAP, sob nº 218.283. Resultados: emergiram as seguintes categorias: disparidades nas orientações no alojamento conjunto: a amamentação natural; interação dos enfermeiros do alojamento conjunto com as puérperas soropositivas para HIV a respeito da impossibilidade da amamentação. Conclusão: a necessidade de orientação e sensibilização da mulher quanto aos motivos e questões relativas à impossibilidade de amamentar. Descritores: Aleitamento materno, HIV, Enfermagem, Orientação.
Perception of nurses in relation to training services offered through the service of continuous education
Authors: Manhães Letycia Sardinha Peixoto , Pinto Ana Cristina Silva , Izu Marina , Tavares Cláudia Mara de Melo , Rosas Ann Mary Machado Feitosa Tinoco
Published: May 2015

Objetivos: Conhecer a percepção de enfermeiros sobre o processo de aprendizagem do programa de treinamento em serviço e analisar o programa de treinamento em serviço do setor de Educação Permanente. Método: Estudo descritivo, quanti-qualitativo e de Campo, através de uma entrevista semi-estruturada analisada segundo a Análise de Conteúdo de Bardin. Resultados: Emergiram três categorias: Descontinuidade do processo de treinamento, O Tempo como um determinante do processo ensino-aprendizagem e O processo de trabalho como fator decisivo na organização dos treinamentos em serviço. Conclusão: É preciso adequar as necessidades de serviço à forma de apresentação dos treinamentos, levando em consideração a realidade do processo de trabalho, buscando alinhar a efetividade dos treinamentos ao desenvolvimento profissional, minimizando confrontos existentes entre os profissionais treinados e sua resistência às ações de Educação Permanente. Descritores: Educação continuada em enfermagem, Capacitação profissional, Treinamento em serviço.
Professional satisfaction and quality of care in oncology: the vision of health professionals
Authors: Trindade Letícia de Lima , Bordignon Maiara , Ferraz Lucimare , Amestoy Simone Coelho
Published: May 2015

Objetivo: identificar as estratégias utilizadas pelos profissionais da saúde que atuam na oncologia para alcançar a satisfação no trabalho, além dos recursos/ações que poderiam amenizar as fontes de insatisfação e melhorar a qualidade do cuidado. Método: trata-se de uma pesquisa qualitativa e descritiva realizada com 31 profissionais de uma equipe de saúde multidisciplinar que atua na Unidade de Internação Oncológica de um hospital geral localizado no Estado de Santa Catarina. Os dados foram coletados por meio de entrevista semiestruturada e analisados conforme a Análise de Conteúdo. Resultados: a principal estratégia dos profissionais é realizar um trabalho que auxilie o paciente a enfrentar as dificuldades impostas pela doença. Entre os recursos emergiram o aumento no quadro de funcionários, atuação multidisciplinar, minimização da rotatividade e a educação permanente dos trabalhadores. Conclusão: destaca-se a importância de angariar esforços em prol da incorporação de tais recursos/ações como forma de reduzir o desgaste do trabalhador. Descritores: Satisfação no trabalho, Saúde do trabalhador, Garantia da qualidade dos cuidados de saúde, Oncologia.
National policy health care of man: vision of managers of SUS
Authors: Adamy Edlamar Kátia , Trindade Letíca de Lima , Teixeira Daiane Cristina , Brambilla Daiane Kutszepa , Galli Kiciosan Bernardi
Published: May 2015

Objetivo: Conhecer como está a implantação da Política Nacional de Atenção Integral à Saúde do Homem (PNAISH) sob a ótica dos gestores do Sistema Único de Saúde em 15 municípios do oeste de Santa Catarina, no sul do Brasil. Método: Trata-se de uma pesquisa qualitativa de caráter exploratório e descritivo. Para a coleta dos dados utilizou-se uma entrevista semi-estruturada. Resultados: Apontam fragilidades no discurso sobre o conhecimento da Política e sobre outros dispositivos que orientam a Atenção Básica no Brasil. As ações realizadas nos municípios estão focadas na detecção do câncer de próstata, aumento do número de consulta médicas especializadas e no controle de algumas doenças crônicas. Conclusão: Evidencia-se a necessidade de capacitar os gestores e de diversos investimentos para implantação e consolidação da PNAISH na realidade pesquisada. Descritores: Saúde do homem, Políticas públicas, Atenção primária à saúde.
Isolating Viral and Host RNA Sequences from Archival Material and Production of cDNA Libraries for High‐Throughput DNA Sequencing
Authors: Xiao Yongli , Sheng Zong‐Mei , Taubenberger Jeffery K.
Published: May 2015

The vast majority of surgical biopsy and post‐mortem tissue samples are formalin‐fixed and paraffin‐embedded (FFPE), but this process leads to RNA degradation that limits gene expression analysis. As an example, the viral RNA genome of the 1918 pandemic influenza A virus was previously determined in a 9‐year effort by overlapping RT‐PCR from post‐mortem samples. Using the protocols described here, the full genome of the 1918 virus was determined at high coverage in one high‐throughput sequencing run of a cDNA library derived from total RNA of a 1918 FFPE sample after duplex‐specific nuclease treatments. This basic methodological approach should assist in the analysis of FFPE tissue samples isolated over the past century from a variety of infectious diseases. © 2015 by John Wiley & Sons, Inc.
Genetic Manipulation of Stenotrophomonas maltophilia
Authors: Welker Elliott , Domfeh Yayra , Tyagi Deepti , Sinha Sanjivni , Fisher Nathan
Published: May 2015

Stenotrophomonas maltophilia is a Gram‐negative, aerobic, motile, environmental bacterium that is emerging as an important nosocomial pathogen with high rates of attributable mortality in severely ill patients. S. maltophilia is of particular concern to patients suffering from cystic fibrosis (CF) as it has been shown to colonize airway epithelial and establish a chronic infection. Here we describe several molecular techniques for the genetic manipulation of this bacterium, including DNA extraction, RNA extraction, conjugation of plasmids from Escherichia coli and allelic exchange. © 2015 by John Wiley & Sons, Inc.
Modular Ligands for Dirhodium Complexes Facilitate Catalyst Customization
Authors: Bachmann Daniel G. , Schmidt Pascal J. , Geigle Stefanie N. , Chougnet Antoinette , Woggon Wolf‐Dietrich , Gillingham Dennis G.
Published: May 2015

Although stereoselectivity is often the focus of ligand optimizations in catalysis, ligand modularity can be used to control many other properties of catalysts. For example, solubility, amenability to purification, and steric shielding of sensitive catalytic intermediates are all important, but seldom appreciated, functions of ligands. We describe a brief and modular approach to various homo‐ and heteroleptic lantern‐type rhodium(II) complexes and perform benchmarking studies with the new catalysts in common rhodium(II)‐catalyzed reactions. We demonstrate the power of ligand modularity by creating catalysts customized for aqueous catalysis or for applications in chemical biology.

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Influence of material property variability on the mechanical behaviour of carotid atherosclerotic plaques: A 3D fluid‐structure interaction analysis
Authors: Yuan Jianmin , Teng Zhongzhao , Feng Jiaxuan , Zhang Yongxue , Brown Adam J. , Gillard Jonathan H. , Jing Zaiping , Lu Qingsheng
Published: May 2015

Mechanical analysis has been shown to be complementary to luminal stenosis in assessing atherosclerotic plaque vulnerability. However, patient‐specific material properties are not available and the effect of material properties variability has not been fully quantified. Media and fibrous cap (FC) strips from carotid endarterectomy samples were classified into hard, intermediate and soft according to their incremental Young's modulus. Lipid and intraplaque haemorrhage/thrombus strips were classified as hard and soft. Idealised geometry‐based 3D fluid‐structure interaction analyses were performed to assess the impact of material property variability in predicting maximum principal stress (Stress‐P1) and stretch (Stretch‐P1). When FC was thick (1000 or 600 µm), Stress‐P1 at the shoulder was insensitive to changes in material stiffness, whereas Stress‐P1 at mid FC changed significantly. When FC was thin (200 or 65 µm), high stress concentrations shifted from the shoulder region to mid FC, and Stress‐P1 became increasingly sensitive to changes in material properties, in particular at mid FC. Regardless of FC thickness, Stretch‐P1 at these locations was sensitive to changes in material properties. Variability in tissue material properties influences both the location and overall stress/stretch value. This variability needs to be accounted for when interpreting the results of mechanical modelling. © 2015 The Authors. International Journal for Numerical Methods in Biomedical Engineering published by John Wiley & Sons Ltd.
An opportunistic relaying‐based incremental hybrid DAF cooperative system
Authors: Bai Zhiquan , Dong Peihao , Gao Shen
Published: May 2015

In this paper, an opportunistic relaying‐based incremental hybrid decode‐amplify‐forward (OR‐IHDAF) scheme that combines robust protocol switch with efficient relay selection is proposed in multi‐relay scenario to cope with the complex and variable channel environments. The proposed OR‐IHDAF scheme can improve the system performance significantly compared with the incremental hybrid decode‐amplify‐forward protocol with the increase of the possible candidate relay nodes and opportunistic relay selection. The analytical expression of the system outage probability of the OR‐IHDAF scheme is presented based on the probability density function and cumulative distribution function, which might be useful to avoid lengthy simulations. Numerical results show the correctness of our theoretical analysis and the performance improvement of the OR‐IHDAF scheme compared with the other current hybrid cooperative protocols and OR‐based cooperative schemes. The effects of the power allocation schemes on the outage probability are also provided. Copyright © 2015 John Wiley & Sons, Ltd.
Circulating Lipocalin 2 Levels Predict Fracture-Related Hospitalizations in Elderly Women: A Prospective Cohort Study
Authors: Lim Wai H , Wong Germaine , Lim Ee M , Byrnes Elizabeth , Zhu Kun , Devine Amanda , Pavlos Nathan J , Prince Richard L , Lewis Joshua R
Published: May 2015

Lipocalin 2 (LCN2) or neutrophil gelatinase–associated lipocalin (NGAL) is expressed in a wide range of cells and pathological states. Mounting evidence suggests lipocalin 2 may be an important regulator of bone homeostasis. Recently it has been suggested LCN2 is a novel mechanoresponsive gene central to the pathological response to low mechanical force. We undertook a prospective study of 1009 elderly women over 70 years of age to study the association between circulating LCN2 and potential associated variables, including estimated glomerular filtration rate, physical activity, and baseline measures of hip bone density and heel bone quality. Osteoporotic fractures requiring hospitalizations were identified from the Western Australian Data Linkage System. Over 14.5 years, 272 (27%) of women sustained an osteoporotic fracture-related hospitalization; of these, 101 were hip fractures. Circulating LCN2 levels were correlated with body mass index and estimated glomerular filtration rate (r = 0.249, p < 0.001 and r = –0.481, p < 0.001, respectively) that modified the association with hip and heel bone measures. Per standard deviation increase in LCN2, there was a 30% multivariable-adjusted increase in the risk of any osteoporotic fracture (hazard ratio [HR] = 1.30, 95% confidence interval [CI] 1.13–1.50, p < 0.001). In participants with elevated LCN2 levels above the median (76.6 ng/mL), there was an 80% to 81% increase in the risk of any osteoporotic or hip fracture (HR = 1.81, 95% CI 1.38–2.36, p < 0.001 and HR = 1.80, 95% CI 1.16–2.78, p = 0.008, respectively). These associations remained significant after adjustment for total hip bone mineral density (p < 0.05). In conclusion, we have demonstrated that circulating LCN2 levels predict future risk of osteoporotic fractures requiring hospitalization. Measurement of LCN2 levels may improve fracture prediction in addition to current fracture risk factors in the elderly, particularly in those with impaired renal function. © 2015 American Society for Bone and Mineral Research.
Violations of the Hückel (4n + 2) Rule
Authors: Gutman Ivan
Published: May 2015

In polycyclic conjugated hydrocarbons the Hückel (4n + 2)‐rule may be violated, so that certain (4n + 2)‐membcred rings cause thermodynamic destabilization. The structural conditions for the occurrence of such an effect are analyze d. Eight examples (of which seven are new) of non‐b enzenoid hydrocarbons are put forward, in which the Hückel rule is disobeyed.
Preparation and Release Behavior of Ethylcellulose Microcapsules Containing Theophylline Dispersed in Cellulose Triacetate Matrices
Authors: Wu Jen‐Chin , Jean Wen‐Jiunn , Chen Hui
Published: May 2015

Using ethylcellulose and cellulose triacetate as co‐wall materials, sustained release microcapsules of theophylline were prepared. The solid drug dispersed in the cellulose triacetate matrices was first prepared by solvent evaporation; then the matrices were microencapsulated by means of coacervation‐phase separation of ethylcellulose from toluene solution on addition of petroleum ether.

The shapes and surface characteristics of theophylline, matrices and microcapsules were examined with a scanning‐electron microscope. The release of theophylline from various particles into distilled water was studied. The microcapsules had good characteristics of sustained release. The period for theophylline to dissolve from ethylcellulose microcapsules containing cellulose triacetate matrices was larger than those from only ethylcellulose microcapsules with a similar ratio of core to wall. The half‐time increased with increasing content of cellulose triacetate. The release pattern which was analogous to that from only ethylcellulose microcapsules obeyed a first‐order equation.
Determination of Anionic Surfactant in Fresh Water and in Sea Water
Authors: Ho Wu‐Hsiung , Lin Bi‐Jen
Published: May 2015

Ion pairs formed from suitable cationic dye and anionic surfactant in water were separated by solvent extraction. The extracts were used subsequently for spectrophotometric determinations. The extraction of ion pairs with various combinations is described. Of the dyes and solvents examined, ethyl violet and p‐xylene are the most useful combination as the cationic dye and extraction solvent. The extracts are determined spectrophotometrically at 611.5 nm; the molar absorptivity is 1, 01 × 105 M−1 cm−1. The detection limit is 1.4 ppb in water. The method is simple, rapid and sensitive. It can also be applied to the determination of anionic surfactants in sea water.
Reactivity of the 1,2‐Diphenytethyl Radical in a Solvent Cage
Authors: Lin Chiou‐Rong , Lin Yuan‐Chuan , Ho Tong‐Ing
Published: May 2015

The 1,2‐diphcnylethyl radical and derivatives were generated from photolysis of tran‐f‐stilbene and its derivatives 1–13 with secondary amines as quenchers. The 1,2‐diphenylelhyl radicals that escaped from the solvent cage were trapped by 2‐methyl‐2‐nitrosopropane (MNP) and were detected by the HPLCEPR method. The yield of the spin adduct is greater for tertiary amines. The smaller yields of the spin adduct formed from secondary amines are ascribed to greater reactivities of the 1,2‐diphenylethyl and dialkylamino radicals within the solvent cage.
Comparison between ab Initio and Modified INDO‐MO Calculations of N20
Authors: Chen Cheng , Sun Kung‐Chung , Lu Li‐Hwa
Published: May 2015

Both STO‐3G ab initio and s‐p separation‐type‐modified INDO semiempirical methods were applied to molecular‐orbital calculation of the N20 molecule. From these two methods, the optimized bond distances between the nearest N atoms (dn‐n) and the most calculated thermodynamic data are close to each other. The positive values of ΔHa° and ΔGa° for the atomization reaction in this work prove that N20 is stable. In contrast to conventional INDO and MINDO/3, but similar to former AMI and MNDO calculations, both ΔHr° and ΔGr° are positive in the formation reaction, which indicates that N20 belongs to the category of high‐energy molecules.
An Alternative Method to Prepare Nitrile Oxides from Primary Nitro Compounds by Using Thionyl Chloride and Triethylamine
Authors: Chen Yao‐Jung , Li Che‐Nan
Published: May 2015

The dehydration of PhCH2NO2 (1a), PhCOCH2NO2 (1b), and MeOOCCH2NO2 (1c) with SOCl2 in the presence of Et3N gave three corresponding nitrile oxides. Each nitrile oxide was trapped by various dipolarophiles to obtain the cycloadducts of 2‐isoxazolines.
Catalytic Conversion of 1,2,3‐Trimethylbenzene Over HY Zeolite
Authors: Ko An‐Nan , Kuo Ching Tung
Published: May 2015

The reaction of 1,2,3‐trimethylbenzene (1,2,3‐TMB) over HY zeolite was investigated in a fixed‐bed flow reactor at 200‐300 °C under atmospheric pressure. The reaction products include toluene, pentamethylbenzene and isomers of xylene, 1,2,3‐TMB and tetramethylbenzene. Based on the time‐on‐stream theory, the types and initial selectivities of these products were determined from plots of product selectivity. 1,2,4‐TMB is initially produced from 1,2,3‐TMB via isomerization whereas o‐xylene, m‐xylene, 1,2,3,4‐ and 1,2,3,5‐tetramethylbenzene were primarily formed by disproportionation of 1,2,3‐TMB. Isomerization and disproportionation obeyed first‐ and second‐order kinetics, respectively; both reactions proceeded via a carbonium ion mechanism with the former occurring by methyl transfer on the benzene ring whereas the latter proceeded through the diphenylmethane transition state. The activation energies are 31.6 and 37.2 kJ mol−1 for isomerizaion and disproportionation, respectively.
Direct Determination of Total Chromium in Sea Water by Graphite Furnace Atomic Absorption Spectrometry with Multiple Injections
Authors: Hsieh Ling‐Ling , Hung Ying‐Ying , Lan Chi‐Ren
Published: May 2015

The method of multiple injections coupled with graphite furnace and atomic absorption spectrometry is applied to direct determination of total chromium at extremely small concentrations in samples of open sea water. The method involves the in situ preconcentration of trace chromium in sea water onto a pyrocoated graphite tube by multiple injections (up to 4 × 90 μL) prior to analysis. The selected ashing temperature is up to 1800 °C, and the background signal caused by high sea‐salt contents will be markedly reduced when the ashing time is prolonged up to 200 s. A CASS‐2 reference sea water has been used as a quality control sample in the analyses of samples of open sea water samples; the results were found to agree with the certified value. Due to the use of a relatively large volume (up to 0.36 mL) of sample for direct determination of trace chromium in sea water, the detection limit for chromium is 0.057 ppb.
Thermodynamics of Complexation Reactions of Lithium Ion with Dibenzo‐14‐Crown‐4 and Its Analogs in Nonaqueous Solvents
Authors: Chen Chi‐Sung , Tsai Zei‐Tsan , Wang Shien‐Jun , Chung Chung‐Sun
Published: May 2015

Formation constants of Li+ complexes with 4‐substituted dibenzo‐14‐crown‐4 (DB14C4; 4‐substituted group: methyl‐, tert‐butyl‐, H‐, bromo‐, chloro‐, formyl‐, nitro‐) ligands were determined by 7Li NMR spectrometry for solutions in nitromethane (NM), acetonitrile (ACN), propylene carbonate (PC), acetone (AC), Pyridine (Py), tetrahydrofuran (THF), dimethyl sulfoxide (DMSO), and N,N′‐dimethyl formamide (DMF). Only a 1:1 complex was formed in solvents with a small or medium donor number. The formation constants of these complexes are strongly influenced by the size of the metal ion – the effect of the size of the cavity, by the solvent and by substituent. The stability of lithium ion with different substituents on DB14C4 decreases in the order methyl‐ > tert‐butyl‐ > H‐ > bromo‐ > chloro‐ > formyl‐ > nitro‐ in various solvents. A good Hammett correlation was found by plotting log Kf vs. ∑σ in PC and AC. The extent of the substituent effect increases as the donor number of solvent decreases. The complexes were both enthalpy and entropy stabilized. The same magnitude of ΔS° value for different substituents indicates formation with a similar configuration upon complexation between crown ether and lithium ion. A slight variation in entropy contribution was observable depending on the nature of the alkyl substituent, whereas a large variation in enthalpic contribution shows a remarkable substituent effect upon complexation; the effect can reach 70% in magnitude.
Synthesis and in Vitro Evaluation of N‐[[4‐[2‐(Carboxyl)‐1‐Cycloalken‐1‐yl]Phenyl]Methyl]Imidazoles as Nonpeptide Angiotensin II Receptor Antagonists
Authors: Lin Ho‐Shen , Rampersaud Ashraff A. , Zimmerman Karen , Steinberg Mitchell I. , Boyd Donald B.
Published: May 2015

A series of nonpeptide angiotensin II receptor antagonists was synthesized via palladium‐assisted cross coupling of aryl stannane and cycloalkenyl triflates and subsequent alkylation of silyl‐protected imidazole. Our compounds, which have a terminal five‐ to seven‐membered cycloalkenyl ring, are compared to DuPont EXP7711, an N‐[(2′‐carboxybiphenylyl)methyl]imidazole, which has a terminal phenyl moiety. Physicochemical properties of the compounds, such as lipophilicity, steric bulk, conformation, and the relative spatial proximity of the 2‐carboxyl and the middle phenyl, are quantitated by computational chemistry. Potency in terms of binding affinity to AT1 receptors in rat adrenal glomerulosa and rabbit aorta is maximized when the terminal ring is aromatic.
Acyl Pyrroles from the Thermal Rearrangement of Bicyclo[2.2.2]Oct‐5‐Ene‐2‐Carbaldoxime Ethers
Authors: Wu Pei‐Lin , Wu Chiou‐Huey
Published: May 2015

In the flash vacuum thermolysis of bicyclo[2.2.2]oct‐5‐ene‐2‐carbaldoxime derivatives, the methyl ether of the parent compound loses methanol to provide the corresponding nitrile. Derivatives carrying a methoxy group at C‐1 appear to undergo the 1‐aza‐Cope rearrangement, followed by loss of some small molecules to yield acyl pyrroles.
Synthesis of Germanium Oligomer from Germanium Dioxide
Authors: Yang Kao‐Chu , Wang Mei‐Huey , Chiang Hung‐Cheh
Published: May 2015

Several crystalline germanium oligomers GenO2n+1· L2·xH2O (L = amino acid or amine) have been prepared and characterized by IR and NMR spectra, EA (elemental analysis), TGA (thermogravimetric analysis) and ICP‐AES (inductively coupled plasma‐atomic emission spectroscopy). Oligomers of this type are based on chains of germanium‐oxygen single and double bonds and synthesized in aqueous solution from germanium dioxide and basic ligands having an amino group. Two basic amino acids and mono‐, and bidentate amines chosen as ligands to react with germanium dioxide gave L‐lysine germanate (1a, 1b, 1c), L‐arginine germanate (2a, 2b, 2c), Cyclohexylammonium hexagermanate (3), N‐methylcyclohexylammonium hexagermanate (4), N,N‐dimethylcyclohexylammonium hexagermanate (5), 2‐aminoethylammonium trigermanate (6), 2‐N′‐methylammo)‐N‐methylethylammonium pentagermanate (7), 2‐(N′N′‐dimethylamino)‐N′N‐dimethylethylammonium heptagermanate (8).
A Tri‐Coordinate‐Magnesium Silylamide Complex: {[(CH3)3Si]2N}2MgO(CH2CH2)2OMg{N[Si(CH3)3]2}2
Authors: Her Tzong‐Yih , Chang Chung‐Cheng , Lee Gene‐Hsiang , Feng Shie‐Ming , Wang Yu
Published: May 2015

The reaction of diethylmagnesium dioxane adduct solution with 1,1,1,3,3,3‐hexamethyldisilazan ((CH3)3SiNHSi(CH3)3) gives {[(CH3)3Si]2N}2MgO(CH2CH2)2OMg{N[Si(CH3)3]2}2 (1); this alkoxomagnesium silylamide in the solid state contains unprecedented three‐coordinate magnesium and oxygen atoms.
The Reaction of 4‐Formylsydnone and Methyl Ketones
Authors: Hung Wei‐Jing , Tien Hsien‐Ju , Chou Tzoo‐Ming , Tien Ling‐Ling , Wu Cheng‐Kwei
Published: May 2015

In the presence of base, 3‐subslituted 4‐fonnyl‐ and 4‐acetylsydnones decarbonylated to afford the corresponding 3‐substituted sydnones. The Claisen‐Schmidt reaction occurred between 3‐substituted 4‐for‐mylsydnones and methyl ketone (such as 4‐acetylsydnones, acetone and acetophenone) in dilute basic solution or electrogenerated basic (EGB) solution.
Synthesis of [1,5‐A]Pyrimidinone Ring Derivatives
Authors: Rashed N. , Mousaad A. , Saleh A.
Published: May 2015

Cyclodehydrogenation of the benzalhydrazino derivatives 5 and 6 gave 6‐cyano‐7‐(4‐methoxyphenyl)‐ 2‐phenyl‐5‐oxo‐1,2,4‐triazolo[1,5‐a]pyrimidine (8) and 6‐cyano‐7‐(4‐methoxyphenyl)‐4‐methyl‐2‐phenyl‐ 5‐oxo‐1,2,4‐triazolo[1,5‐a]pyrimidine (9) respectively. Melhylation, acetylation and benzylation of 8 gave the corresponding N‐methyl, acetyl and benzyl derivatives 10‐12. Methylation of 5 with dimethylsulfate gave 2‐benzalhydrazino‐5‐cyano‐3‐methyl‐6‐(4‐methoxyphenyl)‐3,4‐dihydropyrimidin‐4‐one (6), of which the reaction with acetic anhydride in pyridine afforded the N‐acetylbenzalhydrazino derivative 15. The latter was also prepared from acetylation of 5 followed by medthylation with iodomethane. Acetylation of 5 with boiling acetic anhydride afforded the diacetyl derivative 16, whereas its benzylation gave the mono‐N‐benzyl derivative 14.
Lifetimes and Quenching of the Ā 2A′(υ3′ = 0 – 2) → X̄ 2A″ Fluorescence of HSO
Authors: Hung Wen‐Ching , Lee Yuan‐Pern
Published: May 2015

Fluorescence lifetimes of vibrational levels of the first electronically excited state (Ā 2 A′) of HSO, determined by the technique of discharge flow and laser‐induced fluorescence, are 81 ± 10, 74 ± 8, and 76 ± 14 μs for υ3′ = 0, 1 and 2, respectively. The rate coefficients of quenching of each level by He, N2, O2 and O3 were measured; the coefficients for HSO (Ā, υ3′ = 0 – 2) quenched by O3 arc 35–50 times as great as those of HSO by He.
Temporal Response of SERS to the Potential for 4‐Cyanopyridine Adsorbed on Ag Electrode
Authors: Chang Hua , Lee Long Jeng , Sheu Ung Hua
Published: May 2015

Time‐resolved surface‐enhanced Raman scattering (SERS) was applied to study the response of Raman bands from 4‐cyanopyridine (PyCN) adsorbed on a Ag electrode to variation of the potential; the temporal resolution was 0.1 s. The response of the SERS signals of PyCN was instantaneous to the oxidation potential of Ag electrode. However, delay of the SERS signals was observed while AgCl was reducing. The decay and growth of the SERS bands look place within 1 s in the cases of desorption and adsorption of PyCN on the electrode. It took much longer for PyCN to alter from one adsorption geometry to another on the electrode.
Oxidative Addition vs. Ligand‐Exchange: Fe(II)‐Mixed‐Phenylchalcogenolate Complexes fac‐[PPN][Fe(CO)3(TePh)n(SePh)3‐N] (n = 1, 2)
Authors: Liaw Wen‐Feng , Lai Chia‐Huei , Chiang Ming‐Hsi , Hsieh Cheng‐Kang , Lee Gcne‐Hsiang , Peng Shie‐Ming
Published: May 2015

Diphenyldichalcogenides (PhE)2 (E = Te, Se) react with Fe(0)‐phenylchalcogenolate [PPN] [PhEFe(CO)4] to yield the products of oxidative addition, Fe(II)‐mixed‐phenylchalcogenolate fac‐ [PPN][Fe(CO)3(TePh)n(ScPh)3‐n] (n = 1, 2). Reactions of [PPN][REFe(CO)4] (E=Se, R=Me; E=S, R=Et) and diphenyldichalcogenides yielded ligand‐exchange products [PPN][PhEFe(CO)4] (E=Te, Se, S). The compounds [Fe(CO)3(TePh)(ScPh)2]− (l) and [Fe(CO)3(TePh)2 (2) crystallize in the isomorphous monoclinic space group C2/e, with a = 32.035(8), b = 11.708(6), c = 28.909(6) Å, Z = 8, R = 0.048, and Rw = 0.044 (1); with a = 32.089(5), b= 11.745(2), c = 28.990(8) Å, Z = 8, R = 0.048, and Rw = 0.048 (2). The complexes 1 and 2 crystallize as discrete cations of PPN+ and anions of [Fe(CO)3(TcPh)u(ScPh)3‐n] (n=1, 2), and one half solvent molecule THF. The geometry around Fe(II) is a distorted octahedron with three carbonyl groups and three phenylchalcogenolate ligands occupying facial positions.
Conformation of the Dimethyl Maleate Ligands in a Molybdenum(0) Complex. Crystal Structure of d6trans‐Bis(Dimethyl Maleate)‐Dicarbonyl‐O‐Phenylenediaminemolybdenum(O)
Authors: Lai Chen‐Hsing , Cheng Chicn‐Hong , Cheng Ming‐Chu , Pcng Shie‐Ming
Published: May 2015

The solid‐state structure of Mo(CO)2(DMMA)2(PDA) (DMMA = dimethyl maleate, PDA = o‐phenylenediamine) was determined by X‐ray diffraction of single crystal. The complex crystallizes in the hexagonal space group P6122 with a = 11.085(5), b = 11.085(5), c = 33.653(21) Å, γ = 120°, and Z = 6. The geometry of this bis(DMMA) complex is distorted octahedral with the two CO groups cis to each other and trans to the PDA ligand and the two DMMA ligands trans to each other and cis to the two CO ligands. The orientations of the two trans DMMA ligands are mutually perpendicular and each DMMA ligand eclipses an N‐Mo‐CO vector. The carbon‐carbon double bond of DMMA is bonded to molybdenum unsymmetrically with the olefin carbon adjacent to a coordinated amino group closer to the metal than that adjacent to a carbonyl group. The conformation of each DMMA is that the two ester groups attached to DMMA lie in the regions described by N‐Mo‐C and N‐Mo‐N. Bond‐distance calculations indicate that each keto oxygen of the ester groups in the region described by N‐Mo‐C forms a hydrogen bond with an amino hydrogen on the PDA ligand; this hydrogen bonding is responsible for the observed conformation of the complex. The conformalion of this complex in the solid‐state is in agreement with the results in solution predicted according to 1H NMR spectral data.
Preparation of Palladium(II) and Platinum(II) Phosphine Complexes Promoted by Phase‐Transfer Catalysts
Authors: Lin Ivan J. B. , Liaw Miles D. S.
Published: May 2015

The synthesis of M(PR3)2Cl2 (M = Pd and Pt, R = alkyl or aryl) front K2MCl4 (in H2O) and PR3 (in CH2Cl2) was promoted by the addition of phase‐transfer catalysts (PTC). The greater the amount of PTC used, the more quickly the reaction completed. 31P NMR spectra of some M(PR3)2Cl2 in the presence of free PR3 were measured; these NMR resulls were used to explain problems encountered during the preparations.
Facile Peptide‐Bond Formation Using Polystyrene‐Bound o‐Nitrophenol as an Active Ester
Authors: Duh Shui‐Chyr , Hsieh Hsiao‐Zeng , Chen Shui‐Tein , Wang Kung‐Tsung
Published: May 2015

Using a polystyrene‐bound o‐nitrophenol as the active ester, peptide bond was formed in very high yield (>90%) and optical purity. Peptide fragments with a free C ‐terminal were synthesized in moderate yields (70‐85%) by using an amino acid nucleophile, of which the C‐terminal being protected as a salt of phasetransfer reagent.
Enantioselective Hydrolysis of 2‐Aryloxypropionyl Derivatives by Penicillin V Amidase
Authors: Chen Shui‐Tein , Chang Chun‐Min , Lin Shu‐Ling , Wang Kung‐Tsung
Published: May 2015

Selective hydrolysis of 2‐aryloxypropionyl derivatives 1a‐1e and 2‐phenyloxybutyrate 1f catalyzed by an immobilized penicillin V amidase, Semacylase, was found to show moderately to low enantiomeric excess.
Photochemical Substitution of fac‐Tricarbonyl[P,P′,S‐ (2,2‐Bis (diphenylphosphinomethyl)‐1‐Phenylthiopropane) ]manganese(I) Hexafluorophosphate by Diphenylphosphine
Authors: Tsai Shiou‐Chuan , Cheng Ming‐Chu , Peng Shic‐Ming , Liu Shiuh‐Tzung
Published: May 2015

The title complex underwent ligand substitution by diphenylphosphine to form dicarbonyl[P,P′,S‐(2,2‐bis(diphenylphosphinoniethyl)‐1‐phcnylthiopropane](diphenylphospline)manganesc(I) hexafluorophosphate 2 under photochemical conditions. The crystal structure of complex 2 was determined. The reaction was kinetically independent of the concentration of diphenylphosphine, so a first‐order reaction.
Extended Fluorescence Quenching Analysis as a Remote Probe of Non‐Emissive Exciplexes
Authors: Chow Yuan L. , Johansson Carl I.
Published: May 2015

Extended fluorescence quenching analysis is demonstrated to be an efficient steady‐state method to evaluate the exciplex (excimer) rate constants under certain conditions. This method is attractive as the monitor of only fluorescence of the exciplex's precursor is required for a complete analysis, regardless whether or not the exciplex. Using the interaction of methyl 2‐naphlhoate in its singlet excited state with H2S04 as a kinetic model, for which all the rate constants are known, this method is described and shown to reproduce accurately these rate constants. Limitations and applications of this method are discussed.
Photochemistry of Bicyclo[2.2.2]oct‐5‐Ene‐2,3‐Diones and Reactions of the Intermediates Bicyclo[4.2.0]oct‐2‐Ene‐7,8‐Diones
Authors: Liao Chun‐Chen , Ueng Yih‐Gang
Published: May 2015

Irradiation of bicyclo[2.2.2]oct‐5‐ene‐2,3‐diones la‐c proceeded quantitatively via 1,3‐acyl shifts to yield the corresponding bicyclo[4.2.0]oct‐2‐ene‐7,8‐diones 2a‐c that underwent bisdecarbonylation to afford also quantitatively 1,3‐cyclohexadienes 3a‐c upon further excitation. In contrast the thermolysis of 2c produced lc and 4; the kinetic parameters were found to be ΔH≠ = (90.4 ± 0.8) kJ mot.1 and ΔS≠ = (−12.1 ± 0.1) J K−1 mol−1.
A New Synthesis of Pyrrolo‐3‐Sulfolenes
Authors: Chou Ta‐Shue , Tsai Chung‐Ying
Published: May 2015

A short and novel synthetic route toward pyrrolo‐3‐sulfolene and its N‐mesyl derivative, precursors for the corresponding pyrrolo o‐quinodimethanes, has been developed. The synthesis involves ultrasonic zincation of 4‐bromo‐3‐chloro‐2‐sulfolene and an N‐protected 2‐aminoaldehyde, intramolecular conjugate addition, dehydration and isomerization.
A Convenient Synthesis of 2‐Diazo‐1,3‐Dicyano‐6‐Oxo‐2,6‐Dihydroazulene and its Photochemical Reactions
Authors: Wun Wu‐Che , Huang Tian‐Chyuan , Lin Shih‐Jue , Lin Bing‐Bing , Morita Tadayoshi , Lin Yun‐Shan
Published: May 2015

A facile method was found to synthesize a novel azulenequinone 2‐diazo‐1,3‐dicyano‐6‐oxo‐2,6‐dihydroazulene 4, in yield 90% from the reaction of 2‐amino‐6‐bromo‐1,3‐dicyanoazulene 2 with sodium nitrite in trifluoroacetic acid at 0 °C. The reaction of 4 with methanol, ethanol, acetic acid, benzene, toluene and acetonitrile in photochemical conditions gave related products in yields 82, 82, 90, 85, 40 and 95% of 2‐substituted‐6‐hydroxyazulene derivatives respectively.
Modulation of Troponin‐C Binding to Troponin‐T by Ca2+, Probed by Fluorescence
Authors: Lin Tsung‐I , Mayadevi M. , Dowben R. M.
Published: May 2015

The effects of Ca2+ on the binding interaction between troponin‐C (TnC) and troponin‐T (TnT) and between TnC and troponin‐I (TnI) were studied in both the binary complexes and the presence of other subunits and tropomyosin (Tm). Rabbit skeletal TnC was labeled with 7‐dimemyl‐amino‐4‐methyl‐3‐N′‐meleimido‐coumarin (DACM). The fluorescence titration curve of the labeled TnC with Ca2+ showed a biphasic response; fluorescence was quenched (by 31%) initially but increased (by 64%) in the second phase. In the presence of CaCl2 (3 mM), titrating labeled TnC with TnT caused further fluorescence enhancement (32–34%) of DACM by TnT. In the absence of Ca2+, TnT bound weakly to TnC (Ka < 103 M−1) whereas in the presence of Ca2+, the TnT‐TnC binding affinity increased almost 1000 fold (Ka = 0.42 × 106 M−1). The affinity constant of unlabeled TnC for TnT is 10 – 15 times that of the labeled complex (Ka = (3.4∼ 5.1) × 106 M−1); this value was determined from the binding isotherm of a mixed system consisting of labeled and unlabeled TnC at a fixed ratio upon titration with TnT. Adding Tm to the system weakened the binding of TnT to TnC by at least 50 – 60 percent. Adding Tnl to DACM‐TnC alone also enhanced the fluorescence (20–22%). An affinity constant 108. M−1 for TnC‐Tnl binary complex was obtained. If Tn‐I and the labeled TnC were premixed first in 1:1 stoichiometry, then titrated with TnT, a further fluorescence increase (34%) similar to that in the absence of TnI was observed. The fit of the binding curve shows that Ka of TnT to TnC increased (1.5 × 106 M−1). When TnI was added to the TnC‐TnT complex at the end of titration when the fluorescence binding curve became leveled, quenching (12%) occurred. The latter result indicates that TnI competes with TnT for the same binding sites on TnC. As binding of TnC is at least 100 times as strong to TnI as to TnT, a quenching effect is observed. Furthermore, the conformation of TnC in the TnC‐TnI binary complex may vary from that of TnC alone; binding of TnT to TnC is greatly enhanced (directly or in directly by TnI) in the TnC‐TnI complex. These results indicate that the variation of binding affinity between TnC and TnT as modulated by Ca2+ may play an important role in the Ca+2‐regulation mechanism of muscle contraction.
Syntheses and Characterization of Diastereoisomers of 2′‐O‐Methyladenylyl‐3′,5′‐2′‐O‐Methyladenosine Methyl Phosphonates and 2′‐O‐Methyladenylyl‐3′,5′‐2′‐O‐Methyladenosine Ethylphosphotriesters
Authors: Kan Lou‐Sing , Lin Pen‐Yuan , Yano Junichi
Published: May 2015

The synthesis, separation, purification, and characterization of the R‐ and S‐ forms of 2′‐O‐methyladenylyl‐3′,5′‐2′‐O‐methyladenosine methyl phosphonates ((AmpAm)R or s), 2′‐O‐methyladenylyl‐3′,5′‐2′‐O‐methyladenosine ethylphosphotriesters ((Am(Et)Am)H or s), and 2′‐O‐methyladenylyl‐3′,5′‐2′‐O‐methyladenosine are described.
Formation of Triplexes of Diastereoisomers of 2′‐O‐Methyladenylyl‐3′,5′‐2′‐O‐Methyladenosine Ethylphosphotriesters and 2′‐O‐Methyladenylyl‐ 3′,5′‐2′‐O‐Methyladenosine Methyl Phosphonates with Polyuridylic Acid and Polythymidylic Acid: A Steric Effect
Authors: Kan Lou‐Sing , Koo William , Yano Junichi
Published: May 2015

The triplex formation of diastereoisomers of 2′‐O‐methyladenylyl‐3′,5′‐2′‐O‐methyladenosine ethylphosphotriesters and 2′‐O‐methyladenylyl‐3′,5′‐2′‐O‐methyladenosinc methyl phosphonates with polyuridylic acid and polythymidylic acid was monitored by UV spectral mediods. Possible steric effects on the stability of the triplex are discussed with the aid of simulated chemical structures.
Distribution of Europium Ions in Ion‐Exchanged NaX and NaY Zeolites
Authors: Liu Shang‐Bin , Shu Yau‐Jen , Chang Chau‐Ting
Published: May 2015

The chemical environments of europium‐exchanged NaX (Si/Al =1.16) and NaY (Si/Al = 2.29) zeolites have been investigated by means of 129Xe NMR and isotherm measurements of adsorbed xenon. EuNaX and EuNaY samples with varied concentrations of Eu cations were subjected to diverse chemical and thermal treatments, namely dehydration, reduction, oxidation, and re‐reduction.

Thermal analyses of hydrated EuNaX and EuNaY samples indicate that both the structural stability and the saturation concentration of water increase with increasing Eu content. For dehydrated EuNaY zeolites, the Eu3+ cations tend to replace Na+ ions at S2 sites and tend to be located in framework supercages; similar behavior is found for Eu2+ ions after reduction. After subsequent oxidation, Eu3+ ions migrate from supercages into small sodalite and/or D6R cages; similar results were deduced for samples after re‐reduction. In contrast to the behavior observed in EuNaY, Eu3+ ions tend to exchange for Na+ ions in the sodalite and/or D6R cages in dehydrated EuNaX zeolites, regardless of the thermal treatment; this behavior is ascribed to the existence of unlocalized S3 Na+ in EuNaX samples.
Syntheses and Crystal Structures of Bis‐Citrato, Bis‐Citramalato and Bis‐Malato Germanate(IV) Complexes
Authors: Chiang Hung‐Cheh , Yang Kao‐Chu , Ueng Chuen‐Her
Published: May 2015

Bis‐citrato1a‐d, bis‐citramalato2and bis‐malato3germanate(IV) complexes were synthesized from germanium dioxide and citric acid, citramalic acid and malic acid respectively and were identified with IR, NMR and elementary analysis. Crystal 1a is triclinic, space group P1 with a = 7.919(2), b = 7.968(3), c = 9.605(3) Å, α = 94.25(3), β = 108.03(2), γ= 113.05(3)°, Z = 1, and the final residue, R(F), is 0.033 for 2583 reflections. Crystal 2 is monoclinic, space group C2 with a = 10.226(4), b = 12.802(4), c = 6.141(1) Å, β = 100.75(2)°, Z = 2, and the final residue, R(F), is 0.034 for 934 reflections. Both1aand2have slightly distorted octahedral structures with citrate or citramalate ions as a tridentate ligand that forms five‐, six‐ and seven‐membered rings with the central metal. There is a two‐fold axis through the central atom of compound2instead of the inversion center of1a. Same structures for these six complexes are indicated because the spectral patterns of the other four compounds,1b‐dand3, are similar to those of compounds1aand2.
Synthesis of Aryl α,α‐Difluoroalkyl Ketones as Potent Inhibitors of Cholesterol Esterase
Authors: Lin Gialih , Liu Hsiao‐Chien , Wu Fang‐Chen , Chen Show‐Jane
Published: May 2015

Aryl α,α‐difluoroalkyl ketones were synthesized from the reaction of ethyl α,α‐difluoroacylate with aryl lithium at −78°C or from the coupling of aryl iododifluoromethyl ketone with 1‐alkene in the presence of tetcrakis(triphenylphosphine)palladium(0). These compounds were potent inhibitors of pancreatic cholesterol esterase with Ki values in the range 15 μM‐20 nM.
Determination of Organophosphorus Pesticides in Water Using C18 or Florisil Sep‐Pak Cartridge and Gas Chromatography with Flame‐Photometric Detection
Authors: Wang Wan‐Kung , Huang Shang‐Da
Published: May 2015

Simple methods for the concentration and clean‐up of fifteen organophosphorus pesticides in water using a C18 Sep‐Pak cartridge or a Florisil Sep‐Pak cartridge and subsequently determining the pesticides by gas chromatography with flame photometric detection have been developed. The conditions for stepwise or simultaneous desorption of these pesticides from the Sep‐Pak cartridges are given.
Determination of Trace Arsenic and Selenium in Water Samples by Inductively‐Coupled‐Plasma Mass Spectrometry
Authors: Jiang Shiuh‐Jen , Lu Pei‐Ling , Huang Meng‐Fen
Published: May 2015

Utilisation of a miniature anion‐exchanger preconcentration column of Dowex 1‐X8 to increase the sensitivity for As and Se determinations by inductively‐coupled‐plasma mass spectrometry (ICP‐MS) is described. The ion signal was enhanced were 15 fold for As and 20 fold for Se. The multielement detection limits were 2 ppt (ng/L) and 33 ppt for As and Se, respectively. This flow injection ICP‐MS method was applied to the determination of trace levels of arsenic and selenium in riverine reference material SLRS‐2 and spring water samples.