bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ligand Topology Effects on Olefin Oxidations by Bio‐Inspired [FeII(N2Py2)] Catalysts
Authors: Mas‐Ballesté Rubén , Costas Miquel , van den Berg Tieme , Que Lawrence 
Published: July 2006

AbstractLinear tetradentate N2Py2 ligands can coordinate to an octahedral FeII center in three possible topologies (cis‐α, cis‐β, and trans). While for the N,N′‐bis(2‐pyridylmethyl)‐1,2‐diaminoethane (bpmen) complex, only the cis‐α topology has been observed, for N,N′‐bis(2‐pyridylmethyl)‐1,2‐diaminocyclohexane (bpmcn) both cis‐α and cis‐β isomers have been reported. To date, no facile interconversion between cis‐α and cis‐β topologies has been observed for iron(II) complexes even at high temperatures. However, this work provides evidence for facile interconversion in solution of cis‐α, cis‐β, and trans topologies for [Fe(bpmpn)X2] (bpmpn=N,N′‐bis(2‐pyridylmethyl)‐1,3‐diaminopropane; X=triflate, CH3CN) complexes. As reported previously, the catalytic behavior of cis‐α and cis‐β isomers of [Fe(bpmcn)(OTf)2] with respect to olefin oxidation depends dramatically on the geometry adopted by the iron complex. To establish a general pattern of the catalysis/topology dependence, this work presents an extended comparison of the catalytic behavior for oxidation of olefins of a family of [Fe(N2py2)] complexes that present different topologies. 18O labeling experiments provide evidence for a complex mechanistic landscape in which several pathways should be considered. Complexes with a trans topology catalyze only non‐water‐assisted epoxidation. In contrast, complexes with a cis‐α topology, such as [Fe(bpmen)X2] and [Fe(α‐bpmcn)(OTf)2], can catalyze both epoxidation and cis‐dihydroxylation through a water‐assisted mechanism. Surprisingly, [Fe(bpmpn)X2] and [Fe(β‐bpmcn)(OTf)2] catalyze epoxidation via a water‐assisted pathway and cis‐dihydroxylation via a non‐water‐assisted mechanism, a result that requires two independent and distinct oxidants.
Dopaminergic innervation of the mouse inner ear: Evidence for a separate cytochemical group of cochlear efferent fibers
Authors: Darrow Keith N. , Simons Emmanuel J. , Dodds Leslie , Liberman M. Charles 
Published: July 2006

AbstractImmunostaining mouse cochleas for tyrosine hydroxylase (TH) and dopamine β‐hydroxylase suggests that there is a rich adrenergic innervation throughout the auditory nerve trunk and a small dopaminergic innervation of the sensory cell areas. Surgical cuts in the brainstem confirm these dopaminergic fibers as part of the olivocochlear efferent bundle. Within the sensory epithelium, TH‐positive terminals are seen only in the inner hair cell area, where they intermingle with other olivocochlear terminals expressing cholinergic markers (vesicular acetylcholine transporter; VAT). Double immunostaining suggests little colocalization of TH and VAT; quantification of terminal volumes suggests that TH‐positive fibers constitute only 10–20% of the efferent innervation of the inner hair cell area. Immunostaining of mouse brainstem revealed a small population of TH‐positive cells in and around the lateral superior olive. Consistent with cochlear projections, double staining for the cholinergic marker acetylcholinesterase suggested that TH‐positive somata are not cholinergic and vice versa. All observations are consistent with the view that a small dopaminergic subgroup of lateral olivocochlear neurons 1) projects to the inner hair cell area, 2) is distinct from the larger cholinergic group projecting there, and 3) may correspond to lateral olivocochlear “shell” neurons described by others (Warr et al. [1997] Hear. Res 108:89–111). J. Comp. Neurol. 498:403–414, 2006. © 2006 Wiley‐Liss, Inc.
Überarbeitung der EU‐Bauproduktenrichtlinie – Erfahrungen aus Deutschland aus der Sicht des DIBt
Authors: Jasch Erich , Springborn Matthias 
Published: July 2006

Abstract1. Einführung2. Anforderungen an eine überarbeitete Bauproduktenrichtlinie aus Sicht des DIBt2.1. Verbindlichkeit der CE‐Kennzeichnung2.2. Übergangsfristen2.3. In‐Verkehr‐Bringen2.4. Umgang mit unzureichenden harmonisierten Normen2.5. Abgrenzung der Kompetenzen zwischen den Organen der Europäischen Gemeinschaft und den Mitgliedstaaten3. Ausblick
On the Utilization of Boron Doped Diamond Electrode as a Sensor for Parathion and as an Anode for Electrochemical Combustion Of Parathion
Authors: Pedrosa Valber A. , Miwa Douglas , Machado Sergio A. S. , Avaca Luis A. 
Published: July 2006

AbstractThis work proposes the utilization of a boron doped diamond (BDD) electrode as a sensor for pesticides and as well as an anode for electrochemical combustion of Parathion in spiked, pure and natural waters. The square‐wave voltammetry was selected as the electroanalytical technique and the Britton–Robinson buffer as the electrolyte. The electrochemical reduction responses of Parathion were analyzed and compared with those previously obtained using a hanging mercury electrode (HMDE). The detection and quantification limits were calculated from the analytical curves both for BDD and HMDE in Milli‐Q water (2.4 and 7.9 μg L−1 and 3.9 and 12.8 μg L−1 respectively) showing only a slight improvement when used BDD. However, if the application involves polluted natural waters the improvement is accentuated due to the very low adsorption characteristics of BDD, which prevent the fouling of electrode surface by organic pollutants. The BDD was also used as anode for electrochemical remediation of Parathion contamination. In this case, electrolysis was carried out in high positive potential (3.0 V) and lead the electrochemical combustion of Parathion to CO2 and H2O, as measured by the diminishing of total organic carbon in the electrolyte.
Probiotics: Application of “healthy” bacteria to liver transplant recipients
Authors: Levitsky Josh 
Published: July 2006

Abstract

Bacterial infections frequently occur early after liver transplantation. We recently reported significant progress with a synbiotic composition, consisting of one lactic acid bacteria (LAB) and one fiber, which reduced the infection rate from 48% (with selective bowel decontamination) to 13%. Now, our aim is to study if a combination of different LAB and fibers would further improve outcome. A prospective randomized double-blind trial was undertaken in 66 liver transplant recipients. All patients received enteral nutrition immediately post-operatively. Comparison was made between one group (A) receiving a composition of four LAB and four fibers and another group (B) receiving the fibers only. The treatment started the day before surgery and continued for 14 days. Thirty-day infection rate, length of hospital stay, duration of antibiotic therapy, non-infectious complications and side effects of enteral nutrition were recorded. The incidence of post-operative bacterial infections was significantly reduced; being 48% with only fibers and 3% with LAB and fibers. In addition, the duration of antibiotic therapy was significantly shorter in the latter group. In both groups, mainly mild or moderate infections occurred. Fibers and LAB were well tolerated. Early enteral nutrition supplemented with a mixture of LAB and fibers reduces bacterial infection rates following liver transplantation. Treatment with only fibers led to a low incidence of severe infections.
Suitability of Molluscs as Bioindicators for Meadow‐ and Flood‐Channels of the Elbe‐Floodplains
Authors: Foeckler Francis , Deichner Oskar , Schmidt Hans , Castella Emmanuel 
Published: July 2006

AbstractThe goals of the subproject “molluscs” within the inter‐disciplinary research project “Indicator systems for the characterisation and prediction of ecological changes in floodplain systems” were:– develop further existing mollusc‐based indicator systems of site quality and to test their transferability,– characterise grassland sites within the recent floodplains of three study areas along the Elbe River,– analyse the relationships between indicator species‐/groups and abiotic parameters,– compile and use selected species traits in the analytical process.The results clearly show several characteristic species groups related to the hydrology of the sites (i.e. inundation and desiccation regime) and on to the degree of agricultural use. These dependencies can be interpreted by the simultaneous analysis of the species traits.“Models” are proposed, that are applicable to nature protection measures at the landscape scale. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Orally administered, colon‐specific mucoadhesive azopolymer particles for the treatment of inflammatory bowel disease: An in vivo study
Authors: Roldo Marta , Barbu Eugen , Brown James F. , Laight David W. , Smart John D. , Tsibouklis John 
Published: July 2006

AbstractRadiolabeled congeners of a series of azopolymers have been synthesized and characterized. The in vivo (rat) gastrointestinal transit profile of millimeter‐sized particles of these azopolymers has been determined and used to facilitate the selection of a candidate material for therapeutic applications. The efficacy of the selected material as a protective coating for the colonic mucosa has been tested in a hapten‐reactivated, in vivo model of inflammatory bowel disease: 7 days after reactivation of the condition, the myeloperoxidase activity of animals that had received doses of the selected azopolymer was determined to be at the same level as that of healthy animals or that of the negative control group, highlighting the therapeutic promise of this material. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Resistance of Vigna unguiculata (cowpea) seeds to Callosobruchus maculatus is restricted to cotyledonary tissues
Authors: Domingues Sarah JS , Melo Francislete R , Aguiar Juliana M , Affonso Adriana G , Giuli Jucélia SA , Rose Juliana L , Sales Maurício P , Machado Lara F , Azevedo Cassiana R , da Cunha Patrícia C , Uchoa Adriana Ferreira , de Oliveira Antônia Elenir Amâncio , Xavier‐Filho José , Fernandes Kátia VS 
Published: July 2006

AbstractWe have investigated the survival of Callosobruchus maculatus larvae when reared on resistant IT81D 1045 Vigna unguiculata seeds, whose resistance has been associated with variant forms of vicilins. Here, we present data which show that larvae of C. maculatus feeding on embryonic axis of resistant cowpea reach a mass of around 28 times higher than those feeding on cotyledonary tissues. Additionally, incorporation of 5–10% of embryonic axis flour on artificial seeds made of resistant flour restores toxicity of seeds to the bruchid. Vicilins purified from both susceptible and resistant embryonic axis had no deleterious effects either on insect development or on insect survival until a level of 4% of incorporation. In contrast, vicilins from resistant cotyledons show an LD50 (50% lethal dose) and WD50 (half weight dose) of 2%. Total vicilin contents of embryonic axes were around two times lower than in cotyledonary tissues, while proteolytic activities of all four proteinase classes were always higher in the former tissues. By 2D‐PAGE we visualized eight protein spots, which seem to be exclusively found on resistant cotyledons. Copyright © 2006 Society of Chemical Industry
Development and performance advantages of industrial, automotive and aviation synthetic lubricants
Authors: Law D. A. , Lohuis J. R. , Breau J. Y. , Harlow A. J. , Rochette M. 
Published: July 2006

AbstractThe study and use of some types of syntbetic lubricants can be traced back 50 years.1 Within the past twenty years, rapid advances in technology have resulted in syntbetic lubricants that can operate satisfactorily over temperature extremes well beyond the capabilities of conventional petroleum‐based oils. Current emphasis is on the ability of some types of synthetic lubricants to allow more efficient system operation, with concomitant energy savings and extended equipment and oil life. Several definitions have been proposed for synthetic lubricants. In this paper, the authors define a synthetic lubricant as a product which consists of base fluids manufactured by chemical synthesis and containing necessary performance additives. Thus the base fluids are tailored, through specific chemical reactions, to meet predetermined physical and chemical quality targets. In this paper, discussion will be limited to (a) a review of the types of chemicals which have been studied for use in synthetic lubricants and (b) selected application data which dramatise some of the advantages gained through use of the synthetic lubricant.
Lubrication of gears with synthetic lubricants
Authors: Laukotka E. M. 
Published: July 2006

AbstractThis paper looks at the gear types and operating conditions to which synthetic lubricants are most suited, in terms of both economy and technical benefits. In examining the characteristics of, particularly, worm and non‐positive (friction wheel) gears, data is presented for operating temperature, boundary torque, traction coefficient and friction coefficient, showing the relative advantages in extreme conditions of polyglycols, and other synthetics.
Chemical, physical and technological properties of polyethers as synthetic lubricants
Authors: Kussi S. 
Published: July 2006

AbstractAn extensive range of base fluids has been considered for the formulation of partially and fully synthetic lubricants. In this paper, polyethers are discussed in relation to their tribological properties and chemical structure. Physical properties are reviewed, including water solubility, viscosity‐pressure and thermal stability. Oxidation stability is discussed, and tribological examination shows significant advantages of polyethers, with various additives, in friction, gear and other tests, compared with mineral oils.
Behaviour of synthetic oils in aero engines
Authors: Maier K. 
Published: July 2006

AbstractWithin the framework of the high safety requirement imposed on aero engines, it is understandable that the oil for these engines should also be subject to high quality requirements. These have risen over the years alongside engine performances up to supersonic flight, where mineral oils could no longer meet the demands imposed by such high‐performance engines. They have been superseded by synthetic ester oils, especially because of their more suitable viscosity‐temperature behaviour. This paper deals with the behaviour of these synthetic oils in aero engines and concentrates on the thermo‐oxidative strength and the effects on the engine oil and the engine itself.
Scoring tests of aircraft transmission lubricants at high speeds and high tem peratures
Authors: Winter H. , Michaelis K. 
Published: July 2006

AbstractAircraft engines contain gears that have to be lubricated under conditions of high speeds and extremely high temperatures, In this field of application scoring damage can occur. In Europe and partly also in the USA the scoring load capacity of gear oils is expressed in terms of FZG Scoring Load Stage; the FZG Gear Test Rig is described. The normal test procedure A/8.3/90 as standardised in DIN 51 354 using A‐type gears at a pitch line velocity of v = 8.3 m/s and a starting oil temperature of 90°C is presented. A modified procedure at double speed and increased oil temperature A/16.6/140 is discussed. The scoring load capacity of aircraft transmission lubricants is expressed worldwide in Ryder Gear Test results. Because of the high costs and problems with the availability of test gears a modified FZG Ryder Test was developed. The method is presented and comparative results of typical aircraft engine oils in the FZG, the FZG‐Ryder and the original Ryder Gear Test are shown. From this experience it becomes obvious that alternative test methods for the evaluation of scoring load capacity of aircraft transmission lubricants can be available in the near future.
Fate of amine antioxidants during thermal oxidative ageing of neopentylpolyol ester oils: Part 1
Authors: Zeman A. , Römer R. , Von Roenne V. 
Published: July 2006

AbstractThe thermal‐oxidative degradation of PAN/OPAN in the primary stage in a pentaerythritol ester at 200°C was characterised by the recombination of aminyl radicals giving the corresponding dimers. Primary transformation products such as quinone imines, anils and benzophenoxazone derivatives were also found in small concentrations. A major contribution by the nitroxyl radical is not evident, and the supposed combination of an aminyl radical with the fatty acid chain of the ester was not detected.
Wear and fatigue problems in connection with water‐based hydraulic fluids
Authors: Spikes H. A. 
Published: July 2006

AbstractWater‐containing fluids are widely used in hydraulic applications where there is a significant risk of fire, as in underground mining and metal working applications. Although primarily intended as power transmitting media, hydraulic fluids need to possess a modicum of lubricating ability to limit wear, seizure and contact fatigue of pumps and other rubbing parts. Unfortunately water‐based hydraulic fluids generally show significantly poorer wear and rolling‐contact fatigue performance than mineral or synthetic oil‐based fluids of similar viscosity and this means that pumping equipment usually has to be derated when used with water‐based fluids. This paper examines the poor wear and fatigue performance of water‐based fluids and discusses, in some detail, the origins of this poor performance and the ways it can be mitigated.
Synthetic base stocks for low viscosity motor oils
Authors: Willschke A. , Humbert D. , Rossi A. 
Published: July 2006

AbstractVarious oil formulations were studied in order to ascertain their suitability for use in automobile engine applications. They are characterised according to viscosity, VI, pourpoint and Noack volatility, and the results presented for elastomer compatibility, oxidation resistance and Cu/Pb bearing corrosion, wear, groove filling and viscosity increase in engine tests. The paper concludes that a blend of PAO and polyolesters is a useful component of a SAE 10W‐30 semi‐synthetic motor oil.
Synthetic lubricants in precision mechanisms — an overview
Authors: Tillwich Maria 
Published: July 2006

AbstractThis paper looks at the speciality application field of precision mechanisms, the tribological regime under which they operate, and the consequent requirements for precision lubricants. These include low evaporation rate, good drop cohesion, high ageing stability, resistance against contamination, and particularly an inertness in relation to polymers and lacquers.The range of lubricants available today is reviewed in relation to these requirements and to the materials likely to be used in precision instruments and mechanisms, and it is concluded that since no one lubricant can solve all the problems encountered in specific mechanisms, the selected lubricant is a compromise.
Synthetic and HVI compressor lubricants
Authors: Miller J. W. 
Published: July 2006

AbstractThis paper reviews the optimum synthetic and semi‐synthetic lubricants for various types of compressors and gases being compressed. Several applications are given involving centrifugal, rotary, and reciprocating compressors. Gases include air, refrigerant, natural and other hydrocarbons, chemical processing and industrial. Included also are food grade air compressor applications. In addition, microlube systems for once‐through cylinder lubrication of large reciprocating compressors designed to minimize gas contamination are also described.
Correlations between the structure, physical and rheological properties in the class of neopentylpolyol esters used as lubricating oils
Authors: Nutui R. , Maties M. , Nutui M. 
Published: July 2006

AbstractThis paper examines the correlation between the physical and rheological properties of neopentypolyol ester used as a base oil for synthetic lubricants and the alkyl clash of the carboxylic acid used in preparation of the esters. Kinematic viscosity, viscosity index, flash point and freezing point were examined for fluids prepared by the authors, and their relationships to length and nature of the chains. The resulting data are presented.
EPR study of antioxidant action of P,p'‐dioctyldiphenyl amine
Authors: Kozakowski G. , Kolodziejski W. 
Published: July 2006

AbstractThis paper reports the use of Electron Parametric Resonance (EPR) for preliminary investigation of radicals formed from P,p'‐dioctyldiphenylamine (‘Irganox’, an antioxidant) during heating in a synthetic aviation lubricant base oil di‐2‐ethylhexylsebacate. Relative concentrations of radicals were found to be dependent on temperature. The results seem generally to support the concept that the antioxidant concerned is an effective scavenger of certain reactive peroxide radicals.
Tailor‐making polyalphaolefins
Authors: Shubkin R. L. , Kerkemeyer M. E. 
Published: July 2006

AbstractThe production of polyalphaolefins (PAOs), an important class of synthetic functional fluids, can be better controlled to form materials with given sets of desired properties than can the production of analogous petroleum based fluids. Until now, commercial PAOs have been based almost exclusively on 1‐decene as the starting material. Furthermore, they have been sold on the basis of the viscosity at 100 °C. Work at the authors' company has shown the need to focus attention on other physical properties for various alternative applications. Important properties may or may not include low temperature viscosity, pour point, volatility, high temperature stability, flash and fire point, and oxidative stability. The current work shows how the physical properties of the PAO product can be controlled by the judicious choice of starting olefin, reaction catalyst and co‐catalyst, reaction temperature, reaction time, and other pertinent reaction parameters. Comparisons are made between PAOs and hydrocracked mineral oils.
Wear characteristics of some internally lubricated and reinforced engineering polymer composites
Authors: Tewari U. S. , Bijwe J. , Logai C. M. 
Published: July 2006

AbstractAn interesting characteristic of abrasion is the dependence of the wear rate on the particle size of the abrasive grits used to lubricate the abrasive papers. Three types of polymers, PTFE, PA, PI, several of their composites, and three metals were selected for studying the effect of particle size on wear rate. The pins were abraded against Sic abrasive papers of various mesh sizes under constant loading in multi‐pass conditions. For some of the polymers and their composites (PA and PEI) the size effect on wear rate was similar to that for the metals. Beyond a critical particle size, no increase in wear was found with increasing particle size. On the other hand, PTFE, PI, and their composites showed the opposite effect. SEM and EDAX were used to investigate the related mechanisms.
The shear stress properties of ester lubricants in elastohydrodynamic contacts
Authors: Chang H.‐S. , Spikes H. A. , Bunemann T. F. 
Published: July 2006

AbstractThis paper describes a systematic study into the influence of molecular structure on lubricant shear stress in elastohydrodynamic (EHD) contacts. An infrared emission technique has been employed to measure surface temperatures in an EHD contact and thence to determine the shear stress profile of lubricant films therein. The effect of structure on shear stress has been investigated by comparing the behaviour of a range of well‐characterised, closely related, ester base fluids. Considerable variations in shear stress response to EHD conditions have been observed, depending upon the type and structure of the ester.