bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Carbon‐Rich Hybrid Foam from GAP‐Modified Polyurethane
Authors: König Alexander , Kroke Edwin 
Published: September 2008

Abstract4,4′‐Diisocyanato diphenylmethane (MDI)‐based polyurethanes melt and start to burn at 150–200 °C. Mainly H2O, CO2, CO, HCN, and N2 are formed. The new modified polyurethane shows a different pyrolysis behavior. GAP‐diol (glycidyl azide polymer), which was used as a modifying agent, is a well‐known energetic binder with a high burning velocity and a very low adiabatic flame temperature. The modified polyurethane starts to burn at approximately 190 °C because of the emitted burnable gases, but it does not melt. The PU foam shrinks slightly and a black, solid, carbon‐rich hybrid foam remains. TGA and EGA‐FTIR revealed a three‐step decomposition mechanism of pure GAP‐diol, the isocyanate‐GAP‐diol, and PU‐GAP‐diol formulations. The first decomposition step is caused by an exothermic reaction of the azido group of the GAP‐diol. This decomposition reaction is independent of the oxygen content in the atmosphere. In the range of 190–240 °C the azido group spontaneously decomposes to nitrogen and ammonia. This decomposition is assumed to take place partly via the intermediate hydrogen azide that decomposes spontaneously to nitrogen and ammonia in the range of 190–240 °C. The second decomposition step was attributed to the depolymerization of the urethane and bisubstituted urea groups. The third decomposition step in the range of 500–750 °C was attributed to the carbonization process of the polymer backbone, which yielded solid, carbon‐rich hybrid foams at 900 °C. In air, the second and the third decomposition step shifted to lower temperatures while no solid carbon hybrid foam was left. Samples of PU‐GAP‐diol, which were not heated by a temperature program but ignited by a bunsen burner, formed a similar carbon‐rich hybrid foam. It was therefore concluded that the decomposition products of the hydrogen azide, ammonia and mainly nitrogen act as an inert atmosphere. FTIR, solid‐state 13C‐NMR, XRD, and heat conductivity measurements revealed a high content of sp2‐hybridized, aromatic structures in the hybrid foam. The carbon‐rich foam shows a considerable hardness coupled with high temperature resistance and large specific surface area of 2.1 m2⋅g−1.
Performance of thin‐film transistors fabricated by sequential lateral solidification crystallization techniques
Authors: Exarchos M. A. , Moschou D. C. , Papaioannou G. J. , Kouvatsos D. N. , Voutsas A. T. 
Published: September 2008

AbstractThe performance of Excimer Laser Annealed (ELA) Thin‐Film Transistors (TFTs), in terms of drain current behaviour in unstressed as well as in DC stressed devices, is presented. The transistors studied were fabricated under different irradiation schemes of a novel Sequential Lateral Solidification (SLS) process. As far as unstressed transistors concerned, drain current transients relaxed through stretched exponential law. Fitting results disclosed that both gate dielectric polarization and carrier recombination mechanisms occurred through transient relaxation. Deep Level Transient Spectroscopy (DLTS) technique was called forth in order to investi‐ gate the origin of carrier recombination mechanisms. DC hot carrier stress measurements, under “worst ageing condition” regime, were conducted in order to probe degradation mechanisms and device reliability standards. Crystal domain size significantly affects threshold voltage degradation. The latter increases with decreasing crystal domain size, due to increased concentration of protrusions in the polysilicon film. Transconductance degradation also depends on crystal domain size, attributed mainly to bulk polysilicon trap generation. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nanotechnology advances in controlled drug delivery systems
Authors: Kiparissides C. , Kammona O. 
Published: September 2008

AbstractNanotechnology advances in drug delivery deal with the development of synthetic nanometer sized targeted delivery systems for therapeutic agents of increased complexity, and biologically active drug products. Therapeutic systems in this class are up to a million times larger than classical drugs like aspirin. Being larger there is more scope for diversity and complexity, which makes their protection much more challenging and their delivery more difficult. Their increased complexity however, gives these systems the unique power to tackle more challenging diseases. Targeted delivery systems can have multiple functions, a key one being their ability to recognize specific molecules which can be located either on the membrane of target cells, or in specific compartments within the cell. A challenging objective of targeted drug delivery is the development of innovative multidisciplinary approaches for the design, synthesis and functionalization of novel nanocarriers for targeted delivery of protein/peptide (P/P) drugs via oral, pulmonary and nasal administration routes as well as the fabrication of “smart” miniaturized drug delivery devices able to release a variety of drugs on demand. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparison of the magnetic behaviour between Co‐ and Ni‐nanostructures embedded in silicon matrices
Authors: Rumpf K. , Granitzer P. , Pölt P. , Šimič S. , Krenn H. 
Published: September 2008

AbstractThe incorporation of Ni‐ and Co‐nanostructures into a porous membrane allows to fabricate nanocomposites with different magnetic properties. The precipitation of metal into the pores is carried out during a galvanic process and Ni as well as Co are deposited utilizing an adequate metal‐salt solution. In case of nickel elongated, needle‐like precipitations with a length up to a few micrometers can be achieved. Cobalt precipitated under comparable deposition conditions exhibits mainly spherical and ellipsoidal particles with a maximum length of about 200 nm. Also the composition of a NiCo‐electrolyte (Ni:Co 2:1) was used to get a broader avenue of physical properties of the nanocomposite. The Incorporation of metal nanostructures into the non‐magnetic silicon‐matrix leads to different magnetic properties depending on the metal species as well as the shape and distribution of the precipitations. Coercivity, squareness and anisotropy can be tailored in varying the geometry and/or spatial distribution of the metal structures as well as the choice of the metal‐species. The spatial distribution of the precipitations within the pores modifies the magnetic interaction among them. The metal‐growth of Ni, Co and NiCo within the templates differs and therefore leading to specific characteristics too. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dielectric characterization of macroporous thick silicon films in the frequency range 1 Hz–1 MHz
Authors: Theodoropoulou M. , Pagonis D. N. , Nassiopoulou A. G. , Krontiras C. A. , Georga S. N. 
Published: September 2008

AbstractMacroporous silicon was fabricated on selected areas on p+ silicon substrate by anodization in HF x Ethanol solution. Pore size was ∼ 130 nm. By high temperature thermal oxidation, a thin SiO2 layer was formed on pore walls. MOS capacitors with Al metallization were then fabricated and the samples were characterized by dielectric spectroscopy (DS) in the frequency range 1 Hz–1 MHz and in the temperature range 173–353 K. The results reveal that at low temperatures the dielectric constant ε ′ is independent of frequency (tox = 20 nm ε ′ ∼ 3.4, tox = 40 nm ε ′ ∼ 2.8, tox = 72 nm ε ′ ∼ 2.6). A theoretical model, based on Vegard's law, which calculates the static dielectric constant of the samples, was used. The calculated theoretical values are in good agreement with the experimental results. Dielectric loss data show that the oxidized samples exhibit values of tanδ < 10–2 which are smaller than those of the non oxidized samples. The obtained dielectric characteristics enable oxidized macroporous silicon thick layers to be good candidates for use in RF isolation on a silicon substrate. Transient current measurements were also performed at room temperature for voltages from 1.0 to 20.0 V in the time interval 1‐100s in accumulation. The analysis of the experimental data reveals that the conductivity is governed by two different conduction mechanisms. In the low applied voltage region the conduction is due to thermally excited electrons, hopping from one state to another. For higher voltages Fowler‐Nordheim (F‐N) tunnelling of electrons through the oxide prevails. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Direct determination of recombinant bovine somatotropin in plasma from a treated goat by liquid chromatography/high‐resolution mass spectrometry
Authors: Le Breton Marie‐Hélène , Rochereau‐Roulet Sandrine , Pinel Gaud , Bailly‐Chouriberry Ludovic , Rychen Guido , Jurjanz Stefan , Goldmann Till , Le Bizec Bruno 
Published: September 2008

AbstractRecombinant bovine somatotropin (rbST) is used in dairy cattle to enhance milk production. Despite the ban on this hormone in some countries, especially in Europe, there is so far no method available for the direct detection of rbST either in milk or in plasma. An analytical strategy has been developed to analyze rbST in plasma, including a purification procedure based on a precipitation with ammonium sulphate, followed by a solid‐phase extraction (SPE)‐based clean‐up on C4 sorbent and precipitation with cold methanol. The hormone was then digested with trypsin and analyzed by liquid chromatography/high‐resolution mass spectrometry (LC/HRMSn) on a linear ion trap coupled with an Orbitrap. The tryptic N‐terminal peptide, specific to the difference between the endogenous and recombinant form of the somatotropin, was fragmented and product ions were analyzed at high mass resolution. Applying this approach to goat plasma allowed the direct detection of 10 ng mL−1 of rbST in fortified samples. It also showed the presence of rbST in plasma collected from a goat treated with the hormone, even 2 days after administration. These results are of a great interest in the field of somatotropin control and undoubtedly constitute a first step in the development of a method for the detection of rbST not only in bovine plasma, but also in other biological matrices such as milk. Copyright © 2008 John Wiley & Sons, Ltd.
Analysis of modified nucleosides in the urine of patients with malignant cancer by liquid chromatography/electrospray ionization mass spectrometry
Authors: Li Hua‐Yu , Wang Shao‐Min , Liu Hong‐Min , Li Juan , Han Dong , Bu Shan‐Shan , Zhang Ming‐Zhi 
Published: September 2008

AbstractAs modified nucleosides reflect altered tRNA turnover which seems to be impaired in the body of cancer patients, they have been evaluated as potential tumor markers. High‐performance liquid chromatography/electrosprary ionization quadrupole time‐of‐flight mass spectrometry (HPLC/ESI‐Q‐TOFMS) was used to identify nucleosides purified from urine in positive ionization mode. Potential nucleosides were assessed by their evident UV absorbance in HPLC and then further examined by mass spectrometric techniques. In this manner, 21 nucleosides were detected in the urine of a patient with lymphoid cancer including three modified nucleosides 5′‐dehydro‐2‐deoxyinosine, N1,N2,N7‐trimethylguanosine and N1‐methyl‐N2‐ethylguanosine, which had never been reported previously. Copyright © 2008 John Wiley & Sons, Ltd.
The role of metaphor in Darwin and the implications for teaching evolution
Authors: Pramling Niklas 
Published: September 2008

AbstractThis article is about the role of metaphor in scientific knowledge formation and reasoning. These issues are studied by means of an example of the theory of evolution through natural selection. The premise is that the theory of evolution contains a set of problems regarding metaphor. A second premise is that these problems have to be handled in one way or another when trying to learn, explain, or discuss the theory. How metaphor plays a role in Darwin's writings is analyzed through examples taken from On the Origin of Species. Which metaphors are used by Darwin and which problems do they solve and raise, respectively? It is shown how Darwin uses a variety of metaphors, and that he grapples with this issue. The findings are discussed in terms of the implications for teaching evolutionary theory. Some inherent difficulties in learning the theory of evolution, and more generally abstract complex scientific knowledge, are discussed. © 2008 Wiley Periodicals, Inc. Sci Ed 93: 535–547, 2009
A scale to measure non‐traumatic military operational stress
Authors: Deans Carolyn , Byrne Don G. 
Published: September 2008

AbstractMilitary operations involve both traumatic and non‐traumatic stressors. The authors developed a scale to measure non‐traumatic operational stressors. In Study 1, a list of stressors identified by military personnel was compared across responses from two operations in East Timor. Exploratory factor analysis yielded three similar factors for each dataset. A confirmatory factor analysis on the combined data determined item placement. Item analysis then reduced the questionnaire to 22 items. In Study 2, the questionnaire was administered to personnel from operations in the Middle East. Correlations with similar scales measured the content validity of the three subscales (work concerns, operational concerns and separation concerns). The authors conclude the questionnaire is a robust measure of operational non‐traumatic stressors applicable across operations. Copyright © 2008 John Wiley & Sons, Ltd.
Differential expression of Fos and Zif268 in the nigrostriatal system after methamphetamine administration in a rat model of Parkinson's disease
Authors: Ishida Yasushi , Kawai Keiichi , Magata Yasuhiro , Ebihara Kosuke , Takeda Ryuichiro , Abe Hiroshi , Yoshimoto Mitsuyoshi , Hashiguchi Hiroyuki , Odagiri Kei , Matsuo Hisae , Nishimori Toshikazu 
Published: September 2008

AbstractThe goal of this study was to examine the topological specificity of methamphetamine‐induced activation of the immediate‐early gene proteins, Fos and Zif268, in the nigrostriatal system in a unilateral 6‐hydroxydopamine (6‐OHDA) rat model of Parkinson's disease with or without intrastriatal grafts of fetal ventral mesencephalon. Methamphetamine (3 mg/kg, i.p.) induced Fos‐like immunoreactivity (FLI) dominantly in the striatum and the globus pallidus (GP) on the intact side as well as in the substantia nigra pars reticulata (SNr) on the lesioned side in the 6‐OHDA rats. Lower levels of methamphetamine‐induced FLI in the striatum and GP on the lesioned side were restored by intrastriatal grafts which could completely suppress the methamphetamine‐induced rotation. In the striatum, a similar tendency could be observed between Fos and Zif268 immunoreactivity following methamphetamine. However, sparse immunoreactivity of Zif268 could be detected in the GP and SNr on both sides in the 6‐OHDA rats. Intrastriatal grafts had little influence on Zif268 expression in these two regions. The differential expression of Fos and Zif268 was observed among the three regions of the nigrostriatal system following methamphetamine in the 6‐OHDA rats. This may suggest that Fos and Zif268 therefore possess gene‐specific and region‐specific functions in the basal ganglia nuclei. Synapse 62:920–926, 2008. © 2008 Wiley‐Liss, Inc.
Analysis of linoleate and linolenate by isomerization with potassiumtertiary butoxide in mixtures oftertiary butanol and ethylene glycol dimethyl ether
Authors: Korver O. , Alderlieste E. T. , Boelhouwer C. 
Published: September 2008

AbstractA simple spectrophotometric procedure is described for determining the content of linoleic and linolenic acid in natural oils. Isomerization is accomplished at 70C with potassiumtertiary butoxide (0.57 M) in 110 min. The absorptivities of linoleic acid (k233=86.9) and linolenic acid (k233=66.9 and k268=46.9) attain a maximum and remain constant thereafter.
Nuclear magnetic resonance determination of bacteriostats
Authors: Dietrich Martin W. , Keller Robert E. 
Published: September 2008

AbstractA rapid high‐resolution NMR method has been developed for the determination of soap and detergent bacteriostats. The method can be used to identify six common commercial bacteriostats (3,4,4′‐trichlorocarbanilide; 3‐trifluoromethyl‐4,4′‐dichlorocarbanilide; 4′,5‐dibromosalicylanildie; 3,5‐dibromosalicylanilide; 3,4′,5‐tribromosalicylanilide; and ehxachlorophene) and all two‐component mixtures prepared from them. This method can also be used to determine the relative concentrations of these bacteriostats in all two‐component mixtures. The precision and accuracy of the method are estimated to be within 3% absolute.
Comparison of practical and laboratory laundering of some modern fabrics
Authors: Hunter R. T. , Kurgan C. R. , Marder H. L. 
Published: September 2008

AbstractThe detergency and redeposition characteristics of several modern fabrics were compared under laboratory and home‐laundering conditions. Good correlation was found between data from laboratory‐controlled practical washing and home laundry although washing in the home was uniformly poorer than in the laboratory. Polyester‐containing fabrics tend to gray by redeposition more than the other fabrics investigated, and the new Permanent‐Press fabrics seem more susceptible to redeposition than their untreated counterparts. A systematic screening of factors affecting the performance of these fabrics in the home laundry indicates that detergent underusage is the major factor for the failure of polyesters to perform as well as cotton in either laboratory or practical laundry screening.
The foam separation of colloidal ferric oxide with an anionic and a cationic surfactant
Authors: Grieves Robert B. , Bhattacharyya Dibakar 
Published: September 2008

AbstractAn experimental investigation is presented of the foam separation of colloidal ferric oxide over the pH range 3 to 12 by using an anionic and a cationic surfactant. A sol containing 1.67 mmole/ liter (93 mg/liter) of trivalent iron can be reduced in concentration to 0.09 mmole/liter by 0.17 mmole/liter dodecyl sodium sulfate (anionic) over pH 4.5 to 8; and to 0.18 mmole/liter by 0.17 mmole/liter ethylhexadecyldimethylammonium bromide (cationic) over pH 10 to 12. Soluble iron species produce poorer separations. Between pH 8 and pH 10 the charge of the colloid is reversed from positive to negative, and for an efficient separation a two‐step process should be used, first with an anionic surfactant and then with a cationic. The charge of the particulates has little effect on the foam separation of the surfactants although the presence of the particulates has a significant effect, as evidenced by residual surfactant concentrations and collapsed foam volumes.
A systematic characterization of the reversion flavor of soybean oil
Authors: Smouse Thomas H. , Chang Stephen S. 
Published: September 2008

AbstractThe volatile flavor compounds in a reverted soybean oil with a peroxide number of 4.3 meq/kg were isolated by a semicontinuous counter‐current vacuum steam‐distillation process, fractionated by repeated gas chromatography, and identified by infrared and mass spectrometry. A total of 71 compounds were identified, which included 19 acids, 39 nonacidic compounds, and 13 tentatively identified compounds. The acids consisted of eight normal saturated acids, nine ॅ,ॆ‐unsaturated acids, a branch‐chain acid, one hydroxy acid, two keto acids, three lactones, and one aromatic acid. The nonacidic compounds consisted of two esters, eight normal saturated aldehydes, two branched‐chain aldehydes, five 2‐enals, three dienals, eight ketones, eight alcohols, six hydrocarbons, and four aromatic compounds.The mechanism of formation of the identified compounds indicated that they were mostly primary or secondary autoxidation products of the hydroperoxides of the unsaturated fatty esters. Since many of the identified compounds were produced from oleic and linoleic acids, it is doubtful that linolenic acid was solely responsible for the reversion flavor.Of the compounds identified two are of unusual interest. They are 1‐decyne and 2‐pentyl furan. The former is the first acetylenic compound reported as the autoxidation products of unsaturated fatty esters which contained only double bonds. The latter imparts to an oil at concentrations of 5‐10 ppm a beany and grassy flavor reminiscent of that of a reverted soybean oil. Since this compound is postulated as being produced by the autoxidation of linolenic acid, it is suggested that the presence of linolenic acid catalyzes the autoxidation of linoleic acid and possibly alters the decomposition pattern of its hydroperoxides.
Air pollution regulation of nonvehicular, organic‐solvent emissions by Los Angeles Rule 66
Authors: Maher G. R. 
Published: September 2008

AbstractIn an effort to further their control of sources emitting organic solvents into the atmosphere, the Air Pollution Control District of Los Angeles County, Calif., successfully secured passage of Rule 66 into law July 28, 1966. Rule 66 specifically relates to the control of organic solvent emissions from stationary sources. This paper directs itself to a discussion of the technical aspects used by the Air Pollution Control District in establishing which organic solvents contribute most significantly to the formation of photomechanical smog, eye irritation, and ozone. It also draws attention to the very specific topography of Los Angeles County. And it suggests that air pollution control authorities elsewhere be made cognizant of this in establishing controls on organic solvent emissions in their localities, so as not to be unnecessarily harsh and restrictive.
Cardiologists' awareness and perceptions of guidelines for chronic heart failure. The ADDress your Heart survey
Authors: Erhardt Leif , Komajda Michel , Hobbs F.D. Richard , Soler‐Soler Jordi 
Published: September 2008

AbstractBackground:Several surveys show that patients with chronic heart failure (CHF) are sub‐optimally managed and treatment guidelines are not implemented in clinical practice.Aims:To investigate awareness and perceptions of the 2005 European Society of Cardiology (ESC) guidelines for CHF.Methods:467 cardiologists from seven European countries completed an on‐line interview using a validated, semi‐structured questionnaire including questions about awareness and relevance of CHF guidelines. To assess agreement with ESC guidelines, three fictitious patient cases were presented and respondents' management choices compared with those of an expert panel based on the guidelines.Results:Awareness of CHF guidelines was high, with 98% aware of any guideline and 65% aware of ESC guidelines. ESC guidelines were considered relevant (51%) or very relevant (38%) for guiding treatment decisions. Up to 92% of respondents perceived that they adhered to the ESC guidelines. For the patient cases, ≤25% made treatment recommendations that completely matched those formulated by the expert panel. Respondents considered patient compliance (52%) and guideline complexity (46%) major barriers to implementation.Conclusion:Cardiologists reported high awareness of and a positive attitude towards ESC CHF guidelines. Provision of guidelines in a concise and accessible format is perceived as a key factor to improve implementation.