bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemistry of Quinuclidines as Nitrogen Bicyclic Bridged‐Ring Structures
Authors: Hamama Wafaa S. , Abd El‐Magid Osama M. , Zoorob Hanafi H. 
Published: March 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
α‐Sodiocarboxylic Acids and Related Sodium Compounds
Authors: Juaristi E. , Munoz‐Muniz O. , Melgar‐Fernandez R. 
Published: March 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Multifunctional Materials Based on Tetrathiafulvalene Derivatives with Binding Sites for Metal Ions
Authors: Dolder Stefan , Liu Shi‐Xia , Decurtins Silvio 
Published: March 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of Boron‐Bridged Anionic C2‐Symmetric Bisoxazolines and Their Application in Asymmetric Catalysis
Authors: Mazet Clement , Kohler Valentin , Roseblade Stephen , Toussaint Aurelie , Pfaltz Andreas 
Published: March 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Cyclodextrins: Heterocyclic Molecules Able to Perform Chiral Recognition. Part 1.
Authors: D'Anna Francesca , Lo Meo Paolo , Noto Renato , Riela Serena 
Published: March 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Sugars with Endocyclic Heteroatoms Other than Oxygen
Authors: Greimel Peter , Spreitz Josef , Sprenger Friedrich K. , Stutz Arnold E. , Wrodnigg Tanja M. 
Published: March 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Practical Syntheses of Selected Insect Pheromones
Authors: Petroski Richard J. , Cosse Allard A. , Bartelt Robert J. , Zilkowski Bruce W. 
Published: March 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Characterization of Adenovirus Serotype 35 Vectors Using Genetically Modified Animals and Nonhuman Primates
Authors: Sakurai Fuminori , Kawabata Kenji , Mizuguchi Hiroyuki 
Published: March 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Application of mixtures of tartaric acid derivatives in resolution via supercritical fluid extraction
Authors: Kmecz Ildikó , Simándi Béla , Székely Edit , Lovász Judit , Fogassy Elemér 
Published: March 2007

AbstractRacemic N‐methylamphetamine (rac‐MA) was resolved with 2R,3R‐tartaric acid (TA) and its derivatives (O,O′‐dibenzoyl‐(2R,3R)‐tartaric acid monohydrate (DBTA) and O,O′‐di‐p‐toluoyl‐(2R,3R)‐tartaric acid (DPTTA)), individually and using them in different combinations. After partial diastereomeric salt formation, the free enantiomers were extracted by supercritical fluid extraction using carbon dioxide as solvent. DBTA and DPTTA are efficient resolving agents for rac‐MA, the best chiral separation being obtained at a molar ratio of 0.25 resolving agent to racemic compound for both resolving agents (eeE = 82.5% and eeE = 57.9%, respectively). Compared with the two other acids, TA is practically unsuitable for enantiomer separation (eeE < 5%). Applying a mixture of one individually active and one ineffective acid in half the equivalent molar ratio, when the acids are in 1:1 ratio in the mixture, the resolution efficiency values obtained exceeded those obtained by using the components individually. Decreasing the molar ratio of resolving agent mixture to 0.25, at which the individual resolving agents give the best chiral separation, the obtained resolution efficiency values did not differ significantly from those expected. The outcome of the resolution process depended only on the amount of the individually active resolving agents in the mixture. Chirality, 2007. © 2007 Wiley‐Liss, Inc.
Stereoselective degradation of fungicide benalaxyl in soils and cucumber plants
Authors: Wang Xinquan , Jia Guifang , Qiu Jing , Diao Jinling , Zhu Wentao , Lv Chunguang , Zhou Zhiqiang 
Published: March 2007

AbstractThe enantioselective degradation of benalaxyl has been investigated to elucidate its behavior in several agricultural soils and plants (cucumber). Racemic benalaxyl was fortified into five types of agricultural soils and sprayed leaves of cucumber plants, respectively. The degradation kinetics and the enantiomer fraction (EF) were determined by normal‐phase high‐performance liquid chromatography (HPLC) with diode array detection (DAD) on the chiral column filled cellulose‐tri‐(3,5‐dimethylphenylcarbamate)‐based chiral stationary phase (CDMPC‐CSP). The process of the degradation of benalaxyl enantiomers followed pseudo‐first‐order kinetics in cucumber plant. However, the dissipation phases of benalaxyl enantiomers in soils were biphasic (“slow‐fast‐slow” process). It has been shown that the degradation of benalaxyl was stereoselective. The results indicated that the (+)‐S‐benalaxyl showed a faster degradation in plants, while the (−)‐R‐benalaxyl showed a faster degradation in Soils 3, 4, and 5. No stereoselective degradation was observed in other soils. Chirality, 2007. © 2007 Wiley‐Liss, Inc.
Post‐treatment of UASB reactor effluent by coagulation and flocculation process
Authors: Jaya Prakash K. , Tyagi V.K. , Kazmi A.A. , Kumar Arvind 
Published: March 2007

AbstractExploratory experiments were performed to test the feasibility of coagulation and flocculation as a post‐treatment process for the effluent of an Upflow Anaerobic Sludge Blanket (UASB) reactor treating domestic sewage. Commonly used coagulants [alum, polyaluminium chloride (PAC), ferric chloride, and ferric sulphate] were utilized in a series of jar tests to determine the optimum coagulant dose. The total and fecal coliforms in the effluent were less than 100,000 MPN/100 mL and 10,000 MPN/100 mL, respectively. It was found that all the tested coagulants were effective in reducing the effluent BOD and SS to less than 20 mg/L and 50 mg/L, respectively. The optimum chemical dosage was 20 mg/L (as Al) for alum 24 mg/L (as Al) for PAC, and 39.6 mg/L (as Fe) for FeCl3 and 17.6 mg/L (as Fe) for FeSO4, respectively. Coagulation–flocculation alone was not sufficient to reduce the fecal coliforms concentration to a permissible limit (1000 MPN/100 mL) for unrestricted irrigation. Thus, it would be necessary to disinfect the coagulated effluent. It was found out that after coagulation, a chlorine dose of 1–2 mg/L can reduce the fecal coliforms to less than 1000 MPN/100 mL. © 2007 American Institute of Chemical Engineers Environ Prog, 2007.
Incorporating multi‐state unit models in composite system adequacy assessment
Authors: Billinton Roy , Li Yifeng 
Published: March 2007

AbstractComponents are usually represented by a two state model in conventional generating capacity and composite generation and transmission system reliability studies. Multi‐state generating unit models create a significant increase in the number of generation contingency states and can result in a considerable increase in the overall solution time. In order to avoid this problem, the derated states are usually amalgamated with the totally forced out state to create the derating‐adjusted forced outage rate (DAFOR). This statistic is also known as the equivalent forced outage rate (EFOR). Studies have shown that modeling large generating units in generating capacity adequacy assessments using DAFOR can provide pessimistic appraisals. Many utilities therefore use multi‐state generating unit representations to assess generating capacity adequacy, in order to obtain more accurate appraisals. There is relatively little published material dealing with the effects of using multi‐state generating unit representations in composite system adequacy assessment. This paper illustrates these effects by application to the IEEE‐Reliability Test System (RTS). Load point and system indices for the test system are presented to illustrate the impact of incorporating multi‐state representations in composite system adequacy assessment. Attention is focused on the effects of model variations including how many derated states should be used in a multi‐state model to obtain a reasonably accurate appraisal. Copyright © 2007 John Wiley & Sons, Ltd.
An approach to the explicit consideration of unreliability costs in transmission expansion planning
Authors: Barros João Ricardo P. , Melo Albert C. G. , da Silva Armando M. Leite 
Published: March 2007

AbstractThis paper proposes a new methodology to explicitly consider unreliability costs in a multi‐stage transmission expansion planning. Starting from a reference plan, alternative expansion plans are derived based on postponement/anticipation of circuit implementations. These plans are then ranked by using an economic index of merit (EIM) and the associated Pareto‐optimal set is obtained through cost/benefit (trade‐off) analyses. The cost/benefit is related to the variation of investments and operational costs of each alternative transmission plan. Besides the usual operational costs (active power losses, fuels, etc.) the unreliability costs, due to random failures in the system, are also considered as operational costs. Therefore, reliability evaluations are carried out for all transmission expansion plans (TEPs) in order to compute reliability indices, such as the Expect Energy not Supplied and Loss of Load Cost (LOLC). To reduce the computational effort, pruning techniques are used to limit the number of possible TEPs. The proposed approach is applied to a configuration of the Brazilian North‐eastern system, considering a planning horizon of 10 years, to identify TEPs that are more balanced in terms of investment and reliability. Copyright © 2007 John Wiley & Sons, Ltd.
Theoretical study of the role of solvent H2O in neopentyl and pinacol rearrangements
Authors: Yamabe Shinichi , Tsuchida Noriko , Yamazaki Shoko 
Published: March 2007

AbstractThe neopentyl and the pinacol rearrangements as examples of Wagner–Meerwein rearrangements were investigated by the use of DFT calculations. As the first reaction, a model of neopentyl chloride (1b) and (H2O)12 was employed. In the reaction, the patterns of CCl scission, methyl migration, and COH formation were analyzed. The calculations have shown that the 2‐methyl‐2‐butanol (6) is formed in two steps with the transient intermediate, neopentyl alcohol (3). The first step is the nucleophilic substitution reaction and is the rate‐determining one. The second step is the dual migration of methyl and OH2 groups. The primary and tertiary carbocations were calculated to be absent in the neopentyl rearrangement starting from the hydrolysis. As the second reaction, the pinacol rearrangement of two substrates 2,3‐dimethyl‐2,3‐butanediol (7) and 2,3‐diphenyl‐2,3‐butanediol (12) was investigated. Acidic aqueous solvent was modeled by H3O+ and 12H2O. The reaction paths were promoted by a hydrogen‐bond circuit of H3O+(H2O)2 and were determined as completely concerted processes. Protonated species and carbocations as intermediates also do not intervene during the pinacol rearrangement. Active functions of proton relays along the hydrogen bonds in the two rearrangements were demonstrated. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007
Membrane porosity control with dextran produced by immobilized dextransucrase
Authors: Seto Hirokazu , Kawakita Hidetaka , Ohto Keisuke , Harada Hiroyuki , Inoue Katsutoshi 
Published: March 2007

AbstractThe porosity of Shirasu Porous Glass (SPG) membranes was controlled continuously with dextran produced by the enzymatic reaction of dextransucrase (DSase). DSase was immobilized inside the pores of an SPG membrane at a density of 1.5 U g−1, and a sucrose solution was subsequently permeated through the DSase‐immobilized SPG membrane to produce dextran from the active site of DSase. Varying the sucrose concentration from 5 to 25 mg L−1, resulted in a change in the rate of dextran produced, due to a decrease in the intermediate formation of the substrate–enzyme complex. Using the Kozeny–Carman equation, and based on the relationship between the pressure loss and pure water permeation rate, the membrane porosity could be varied between 38 and 66% by changing the amount of dextran produced. Copyright © 2007 Society of Chemical Industry
The effect of organic loading rate on the anaerobic digestion of two‐phase olive mill solid residue derived from fruits with low ripening index
Authors: Rincón Bárbara , Travieso Lissette , Sánchez Enrique , de los Ángeles Martín María , Martín Antonio , Raposo Francisco , Borja Rafael 
Published: March 2007

AbstractA study of the effect of organic loading rate on the performance of anaerobic digestion of two‐phase olive mill solid residue (OMSR) was carried out in a laboratory‐scale completely stirred tank reactor. The reactor was operated at an influent substrate concentration of 162 g chemical oxygen demand (COD) dm−3. The organic loading rate (OLR) varied between 0.8 and 11.0 g COD dm−3 d−1. COD removal efficiency decreased from 97.0% to 82.6% when the OLR increased from 0.8 to 8.3 g COD dm−3 d−1. It was found that OLRs higher than 9.2 g COD dm−3 d−1 favoured process failure, decreasing pH, COD removal efficiency and methane production rates (QM). Empirical equations described the effect of OLR on the process stability and the effect of soluble organic matter concentration on the total volatile fatty acids (TVFA)/total alkalinity (TAlk) ratio (ρ). The results obtained demonstrated that rates of substrate uptake were correlated with concentration of biodegradable COD, through an equation of the Michaelis–Menten type. The kinetic equation obtained was used to simulate the anaerobic digestion process of this residue and to obtain the theoretical COD degradation rates in the reactor. The small deviations obtained (equal to or lower than 10%) between values calculated through the model and experimental values suggest that the proposed model predicts the behaviour of the reactor accurately. Copyright © 2007 Society of Chemical Industry
Treatment of high‐level arsenic‐containing wastewater by fluidized bed crystallization process
Authors: Huang Chihpin , Pan Jill R , Lee Maosung , Yen Shihming 
Published: March 2007

AbstractGallium arsenide technology has been widely applied in the communication and optical electronics industries. The process of chip manufacturing produces a stream of wastewater unique in its low flow rate and high arsenic concentration. Fluidized bed crystallization (FBC) technology combines the advantages of a fluidized bed reactor and crystallization. It is highly efficient with low capital and operational costs, while producing no sludge. The waste from the FBC is small in volume, high in crystal purity and recyclable. Jar tests were first performed to evaluate the precipitation of arsenic sulfide. Then a lab‐scale fluidized bed reactor was applied to screen critical operational parameters and the process was optimized to meet the wastewater discharge standard. The results obtained in this study confirmed that the FBC process is capable of treating wastewater containing high concentrations of arsenic, reducing the concentration to µg L−1 levels. Sulfide dosage and operating pH are the two most significant parameters determining the residual arsenic concentration of the effluent, with optimum conditions of pH = 2 and S/As = 2.2 to meet the local discharge limit. Copyright © 2007 Society of Chemical Industry
MR compatibility of EEG scalp electrodes at 4 tesla
Authors: Stevens Todd K. , Ives John R. , Klassen L. Martyn , Bartha Robert 
Published: March 2007

AbstractPurposeTo design and apply a method to quantitatively evaluate the MR compatibility of electroencephalographic (EEG) scalp electrodes based on pulse sequence‐independent metrics.Materials and MethodsThree types of electrodes (constructed primarily of brass, silver, and conductive plastic, respectively) were tested. B0 field distortions, B1 shielding, and heat induction was measured in adjacent agarose and oil phantoms at 4 T. B0 field maps were corrected for distortions caused by the measurement apparatus and passive shim heating, and projections perpendicular to the surfaces of the electrodes were fit, generating cubic coefficients representing the electrode distortion severity. Signal loss in T2‐weighted images was used to determine B1 shielding by the electrodes. Temperature measurements were recorded during the application of a high‐power pulse sequence.ResultsSignificantly different B0 distortions were observed in the three types of electrodes. The B1 shielding detected in all three electrodes is minimal for most human MRI, and no significant heating was detected in the electrodes or adjacent phantom.ConclusionThe three types of electrodes were successfully differentiated in terms of MR compatibility based on pulse sequence‐independent B0 field distortions. J. Magn. Reson. Imaging 2007. © 2007 Wiley‐Liss, Inc.
Effect of bolus length of intraarterial injections on contrast‐enhanced MR‐angiography in patients
Authors: Hashagen C. , Schulte A.‐C. , Bongartz G. , Aschwanden M. , Jaeger K.A. , Huegli R. , Jacob A.L. , Bilecen Deniz 
Published: March 2007

AbstractPurposeTo perform MR‐guided interventions, repetitive injections of contrast agent in the arterial system are necessary. By reducing the intraarterial bolus length during image acquisition and consecutively reducing the gadolinium‐chelate–based contrast agent dose, we focus on a comparable vascular depiction. The tradeoff in reducing bolus length is vascular depiction.Materials and MethodsIntraarterial gadolinium‐chelate injection was performed to depict the femoropopliteal artery and infrapopliteal arteries in six patients. Six measurements with a bolus length of 20% to 100% of the total acquisition time were performed (three‐dimensional [3D] Turbo‐fast low‐angle shot (FLASH) sequence, 1.5 T). Contrast‐to‐noise ratio (CNR) was determined and a consensus reading of vascular depiction was performed.ResultsCNR values comparable 100% of bolus length were obtained for the femoropopliteal artery at ≥40% and for the infrapopliteal arteries at ≥60%. Qualitative analysis demonstrated that a bolus length of ≥60% is necessary to reveal a good diagnostic vascular depiction.ConclusionQuantitatively, a reduction of intraarterial gadolinium‐chelate dosage in patients is possible down to 40% in the femoropopliteal artery and to 60% in the infrapopliteal arteries to acquire a CNR comparable to 100% of bolus length. Qualitatively, however, the bolus length can only be reduced down to 60% for both level to produce a good diagnostic vascular depiction and is, for diagnostic purposes, the limiting factor. J. Magn. Reson. Imaging 2007. © 2007 Wiley‐Liss, Inc.
Kainic acid triggers oligodendrocyte precursor cell proliferation and neuronal differentiation from striatal neural stem cells
Authors: Redondo Carolina , López‐Toledano Miguel A. , Lobo Maria V.T. , Gonzalo‐Gobernado Rafael , Reimers Diana , Herranz Antonio S. , Paíno Carlos L. , Bazán Eulalia 
Published: March 2007

AbstractGlutamate is an excitatory amino acid that serves important functions in mammalian brain development through α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionate (AMPA)/ kainate receptor stimulation. Neural stem cells with self‐renewal and multilineage potential are a useful tool to study the signals involved in the regulation of brain development. We have investigated the role played by AMPA/kainate receptors during the differentiation of neural stem cells derived from fetal rat striatum. The application of 1 and 10 μM kainic acid increased significantly the phosphorylation of the cyclic AMP response element binding protein (CREB), raised bromodeoxyuridine incorporation in O4‐positive oligodendrocyte precursors, and increased the number of O1‐positive cells in the cultures. Increased CREB phosphorylation and proliferation were prevented by the AMPA receptor antagonist 4‐4(4‐aminophenyl)‐1,2‐dihydro‐1‐methyl‐2‐propylcarbamoyl‐6,7‐methylenedioxyphthalazine (SYM 2206) and by protein kinase A and protein kinase C inhibitors. Cultures treated with 100 μM kainic acid showed decreased proliferation, a lower proportion of O1‐positive cells, and apoptosis of O4‐positive cells. None of these effects were prevented by SYM 2206, suggesting that kainate receptors take part in these events. We conclude that AMPA receptor stimulation by kainic acid promotes the proliferation of oligodendrocyte precursors derived from neural stem cells through a mechanism that requires the activation of CREB by protein kinase A and C. In the neurons derived from these cells, either AMPA or kainate receptor stimulation produces neuritic growth and larger cell bodies. © 2007 Wiley‐Liss, Inc.
Opposing short‐ and long‐term effects on muscarinic M1/4 receptor binding following chronic phencyclidine treatment
Authors: Newell Kelly A. , Zavitsanou Katerina , Huang Xu‐Feng 
Published: March 2007

AbstractPhencyclidine (PCP) is a noncompetitive N‐methyl‐D‐aspartate (NMDA) receptor antagonist. Several studies have demonstrated that chronic NMDA receptor antagonist treatment in humans and animals can cause long‐term behavioral changes that are reminiscent of negative and cognitive schizophrenia‐like symptoms. The muscarinic cholinergic system, which is associated with cognitive functions, has been hypothesized to contribute to PCP's mechanism of action. No study, however, has examined the status of M1/4 receptors in the PCP model of schizophrenia. The aim of the present study was to investigate the effects of chronic (14 day) PCP treatment on mouse brain M1/4 receptors in the short term (1 hr and 24 hr) and long term (14 days) after last PCP administration. [3H]pirenzepine was used to target M1/4 receptors. In the short term following chronic PCP treatment, M1/4 binding was significantly increased in regions of the limbic system, caudate‐putamen, cortex, and thalamus (ranging from 56% to 368%), compared with saline‐treated mice. There were no differences in binding between mice treated with PCP for 14 days and sacrificed 1 hr or 24 hr after the final PCP treatment. In the long term following chronic PCP treatment, M1/4 binding was significantly decreased in all of the above‐mentioned brain regions (ranging from 31% to 72%), except in the thalamus, which showed no change. These findings in the long‐term group are similar to those reported in post‐mortem studies of patients suffering from schizophrenia. © 2007 Wiley‐Liss, Inc.