bluuebunny/crossref_metadata_2025_split huggingface dataset:
Solvent and temperature effects on the conformational equilibria of a dihydrobenzo[h]quinolinium fluoroborate
Authors: Rezende Marcos Caroli , Guerrero Juan 
Published: March 2009

AbstractSpectra of the N‐phenyl‐5,6‐dihydro‐2,4‐diphenylbenzo[h]quinolinium tetrafluoroborate (1) and of the N‐phenyl‐5,6,8,9‐tetrahydro‐7‐phenyldibenzo[c,h]acridinium tetrafluoroborate (2) were recorded in various solvents and temperatures. The analysis of the 1H‐NMR spectra of the tetrafluoroborate salt 1, recorded in acetone, acetonitrile, 1,1,2,2‐tetrachloroethane and chloroform, revealed the existence of an equilibrium between two conformers in solution. Tight ion‐pairing in chloroform led to a smaller barrier for interconversion between the two conformers. In more polar solvents, where the dihydrobenzoquinolinium exists as a free cation, theoretical calculations predicted larger barriers. The spectra of 1 in 1,1,2,2‐tetrachloroethane also varied with temperature, resembling at higher temperatures the spectrum in CDCl3 and at 300K spectra in more polar media. Spectra of 2 did not vary with the solvent or the temperature, in an indication of a much higher barrier to conformational interconversion, because of a greater steric hindrance between the N‐phenyl substituent and the dihydrobenzo rings. Copyright © 2009 John Wiley & Sons, Ltd.
Vibration prolongs the cortical silent period in an antagonistic muscle
Authors: Binder Christian , Kaya Ali Ekber , Liepert Joachim 
Published: March 2009

AbstractWe tested whether the silent period, an indicator of inhibitory neuronal activity, is modulated by muscle vibration. Vibration was applied to the right extensor carpi radialis (ECR) muscle in 17 healthy subjects and, as a control experiment, to the dorsal terminal phalanges in 5 subjects. Data before vibration were compared with those during vibration. The cortical silent period (CSP) was evoked by transcranial magnetic stimuli (TMS) during voluntary wrist flexion or during voluntary wrist extension. TMS‐evoked motor potentials (MEPs) of the flexor carpi radialis (FCR) muscle were recorded during muscle relaxation. The mixed nerve silent period (MNSP) was obtained by electrical stimulation of the median nerve during wrist flexion. ECR vibration induced a significant prolongation of the CSP in FCR. CSP increases induced by vibration of the dorsal terminal phalanges were significantly less pronounced. In ECR, the CSP tended to be shortened. MEPs and MNSP remained unchanged. We conclude that vibration enhances inhibitory neuronal properties in a non‐vibrated antagonistic muscle, presumably at a supraspinal level. These results may be relevant for the treatment of spasticity of the upper extremity. Muscle Nerve, 2009
Preparation of composited Nano‐TiO2 and its application on antimicrobial and self‐cleaning coatings
Authors: Wang Rong‐Min , Wang Bo‐Yun , He Yu‐Feng , Lv Wei‐Hua , Wang Jun‐Feng 
Published: March 2009

AbstractComposite nano‐TiO2 with doping Fe3+ and Ag was prepared, and further modified by 3‐methacryloxypropyltrimethoxysilane. They were characterized by Zetasizer Nano ZS Particle and Zeta Potential Analyzer, X‐ray diffraction, UV–Vis spectrophotometer, FT–IR spectra, and transmission electron microscopy. The modified composite nano‐TiO2 was applied to prepare multifunctional fluorocarbon coatings (FCC). Antibacterial activity of multifunctional FCC containing modified composite nano‐TiO2 was investigated. Its photocatalytic antibacterial activity reached 92%. The influence of doping ingredients, amount of composite nano‐TiO2, different light houses, or surface modification was discussed. The surface of FCC cannot be easily smirched by oiliness, dust or water because of hydrophobic fluorosilicone emulsion. It would be an available modern interior building coating for its remarkable photocatalytic antibacterial property as well as self‐cleaning function. Copyright © 2009 John Wiley & Sons, Ltd.
Preparation of phenolic hollow microspheres via in situ polymerization
Authors: Liu Xizong , Li Hejun , Ma Tuomei , Li Kezhi 
Published: March 2009

AbstractBACKGROUND: Phenolic hollow microspheres with a closed structure have a set of outstanding thermal characteristics. In the work reported here, a facile method is introduced to fabricate phenolic closed hollow microspheres by in situ polymerization in oil‐in‐water emulsion. Although in situ polymerization has been widely used to prepare hollow microspheres, it has not been utilized for the preparation of phenolic hollow microspheres.RESULTS: The average particle size of the produced microspheres was about 500 µm. Fourier transform infrared spectroscopy indicated that the phenolic microspheres were partially cured during preparation and a significant number of hydroxymethyl groups remained in the microspheres. Thermogravimetric analysis showed that the thermal decomposition temperature of the phenolic hollow microspheres was 420 °C, and residual weight at 800 °C was 62%. Differential thermal analysis showed that the glass transition temperature of the phenolic hollow microspheres was 200 °C.CONCLUSION: Using in situ polymerization, high thermal performance phenolic hollow microspheres are produced. The resultant product possesses a satisfactory closed hollow structure with controlled morphology. Copyright © 2009 Society of Chemical Industry
A clinical tool to predict failed response to therapy in children with severe pneumonia
Authors: Mamtani Manju , Patel Archana , Hibberd Patricia L. , Tuan Tran Anh , Jeena Prakash , Chisaka Noel , Hassan Mumtaz , Radovan Irene Maulen , Thea Donald M. , Qazi Shamim , Kulkarni Hemant 
Published: March 2009

AbstractSevere pneumonia in children under 5 years of age continues to be an important clinical entity with treatment failure rates as high as 20%. Where severe pneumonias are common, predictive tools for treatment failure like chest radiography and pulse oximetry are not available or affordable. Thus, there is a need for development of simple, accurate and inexpensive clinical tools for prediction of treatment failure. Using clinical, chest radiographic and pulse oximetry data from 1702 children recruited in the Amoxicillin Penicillin Pneumonia International Study (APPIS) trial we developed and validated a simple clinical tool. For development, a randomly derived development sample (n = 889) was used. The tool which was based on the results of multivariate logistic regression models was validated on a separate sample of 813 children. The derived clinical tool in its final form contained three clinical predictors: age of child, excess age‐specific respiratory rate at baseline and at 24 hr of hospitalization. This tool had a 70% and 66% predictive accuracy in the development and validation samples, respectively. The tool is presented as an easy‐to‐use nomogram. It is possible to predict the likelihood of treatment failure in children with severe pneumonia based on clinical features that are simple and inexpensive to measure. Pediatr Pulmonol. 2009; 44:379–386. © 2009 Wiley‐Liss, Inc.
A Young's modulus study of n‐ and p‐type porous silicon
Authors: Oisten Michael K. , Bergstrom Paul L. 
Published: March 2009

AbstractWith the number of MEMS based applications utilizing porous silicon increasing, it has become more important to know the mechanical properties of the material. Using nanoindentation, the Young's modulus of various n‐type and p‐type mesoporous silicon samples has been measured. The porous silicon samples were produced by electrochemical anodization in an ethanoic hydrofluoric acid solution. Anodization conditions were varied to study the impact on Young's modulus due to porosity and pore morphology. The current densities of the p‐type samples were varied between 20 mA/cm2 and 60 mA/cm2 and the n‐type samples current densities were varied between 3 mA/cm2 and 60 mA/cm2. The investigation demonstrated a strong morphological change for n‐type samples which caused a much broader range of Young's modulus values measured. It was also observed that the p‐type samples pore morphologies did not significantly change over the range of current densities used, therefore the changes in the Young's modulus can be attributed to a change in porosity. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The role of residual stress in a Prince Rupert's drop of soda‐lime glass undergoing a self‐sustained and stable destruction/fracture wave
Authors: Chaudhri M. Munawar 
Published: March 2009

AbstractIt is shown experimentally using colour high‐speed framing photography, carried out at 1 million frames per second that in a Prince Rupert's drop made of soda‐lime glass, a self‐sustained destruction/fracture wave can travel at a steady and stable speed of (1700 ± 100) m s–1. It is also shown that this limiting velocity of the destruction/fracture wave, which is considerably smaller than the longitudinal wave velocity of ∼5300 m s–1in this glass, is due to crack bifurcation, which occurs in individual cracks moving at the limiting velocity, at the immediate front of the destruction/fracture wave. Moreover, it is also shown that in the intact part of a Prince Rupert's drop undergoing a self‐sustained destruction/fracture wave, the residual stress state remains approximately unaltered until the intact part comes to within about one mm of the advancing destruction/fracture wave front. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The growth of InAsSbP‐based diode heterostructures with quantum dots as a new material for thermophotovoltaic application
Authors: Gambaryan Karen , Aroutiounian Vladimir , Boeck Torsten , Schulze Marlen 
Published: March 2009

AbstractIn this paper we report our first efforts for the growth of InAsSbP‐based diode heterostructures with (and without) quantum dots on InAs (100) substrates as a new material for TPV application. For the fabrication of self‐assembled strain induced QDs and the growth of lattice matched quaternary InAsSbP emitter cap layer the conventional and “step‐cooling” versions of liquid phase epitaxy have been employed. The morphology, dimensions and distribution density of QDs were investigated by AFM technique. The average density of the QDs was equal (5–7)×109 cm–2, with dimensions of 0.7–12 nm in height and 20–80 nm in width. The investigations of cross‐sectional area of p‐n heterojunctions, morphology of layers surface and calculations of InAsPSb alloys composition have been carried out by SEM‐EDXA equipment. The current‐voltage characteristics, transmission spectra and optical response of n‐InAs/p‐InAs1–x–ySbxPy TPV cells were measured and investigated. The maximum photoresponse is observed near the wavelength of 3.4 μm, which corresponds to the optimum efficiency of TPV cells. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Theoretical investigation of μ‐O‐bridged dinuclear Re complexes: Electronic structure, bonding nature, and absorption spectra
Authors: Nakao Yoshihide , Saito Ken , Sakaki Shigeyoshi 
Published: March 2009

AbstractThe ground state and some low‐lying excited states of [Re2IV(μ‐O)2(NH3)8]4+ (1) and [ReIIIReIV(μ‐O)2(NH3)8]3+ (2) were theoretically investigated with the second‐order Møller–Plesset perturbation theory (MRMP2) and B3LYP methods. Their ground states were assigned to be the 7B and 6B states, respectively, by the B3LYP method, but to be the 1A and 2B states, respectively, by the MRMP2 method. In 1, the DFT‐optimized ReRe distance of the 7B state differs much from the experimental value of similar complex such as [Re2IV(μ‐O)2(Metpa)2] (A1) and [Re2IV(μ‐O)2(Me2tpa)2] (A2) (Metpa: ((6‐methyl‐2‐pyridyl)‐methyl)bis(2‐pyridylmethyl)amine, Me2tpa: bis((6‐methyl‐2‐pyridyl)methyl)(2‐pyridylmethyl)amine) that of 1A state is in good agreement with the experimental one. In 2, the DFT‐optimized ReRe distance of the 6B state differs much from the experimental value of the similar complex, [Re2IV(μ‐O)2(Metpa)2] (B), too, but that of the 2B state agrees well with the experimental value. These results indicate that the ground state of 1 and 2 are the 1A and 2B states, respectively, as assigned by the MRMP2 method. Two large absorption bands about 2.1 and 2.6 eV for A1 and A2 are theoretically assigned to be 11B and 21B states by the MRMP2 method. These energies are calculated to be 2.12 and 2.15 eV by the MRMP2 method, which are in good agreement with the experimental values of the similar complexes. Significant difference in absorption spectra of B from those of A1 and A2 are also discussed, based on MRMP2 calculations. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Rethinking trends in minority participation in the sciences
Authors: Lewis James L. , Menzies Holly , Nájera Edgar I. , Page Reba N. 
Published: March 2009

AbstractBlacks, Hispanics/Latinos, and Native Americans have long been underrepresented in schools and the workplace in science, technology, engineering, and mathematics. Although the monitoring of representation has become a larger and more important enterprise, existing databases make it difficult to discern trends in participation at different stages of science education as well as the magnitude of the differences in representation across racial/ethnic groups. We reanalyze four nationally representative databases to call attention to the difficulties, and we offer a solution—a ratio of representation. Our investigation of the representation of students in the biological sciences indicates that gains in the percentages of non‐Asian minorities in the biological sciences over almost two decades do not exceed their growth in the U.S. population and, furthermore, that their underrepresentation appears to increase as they move through higher education. We call for the development of multiple measures of representation in the sciences, given the complexities of representing representation and the issue's importance for science, public health, and the American polity. © 2009 Wiley Periodicals, Inc. Sci Ed 93:961–977, 2009
Finding their way on: Career decision‐making processes of urban science teachers
Authors: Rinke Carol R. 
Published: March 2009

AbstractThis article reports on a research study investigating the career decision‐making processes of urban science teachers as one element central to understanding the high rates of attrition in the field. Using a longitudinal, prospective, context‐ and subject‐specific approach, this study followed the career decisions of case study teachers over a period of 12 months. All eight of the case study teachers envisioned themselves eventually moving out of classroom teaching positions. Each used an ongoing and active process of decision making to evaluate their professional direction and sought confirmation of their contribution to the field before moving into new roles and responsibilities. This article describes the experiences of several teachers who exemplify these decision‐making processes. These cases suggest potential benefits for differentiated roles, professional mentoring, and recognition and feedback from professional communities. © 2009 Wiley Periodicals, Inc.Sci Ed93:1096–1121, 2009
Synthesis and Evaluation of pH and Thermosensitive Pectin‐Based Superabsorbent Hydrogel for Oral Drug Delivery Systems
Authors: Pourjavadi Ali , Barzegar Shahram 
Published: March 2009

AbstractThe purpose of this study was to produce intelligent pectin‐based superabsorbent polymers (SAP) to be used as pH‐ and thermosensitive carriers for the controlled delivery of non‐steroidal anti‐inflammatory drugs (NSAIDs). The superabsorbent formation was confirmed by Fourier transform infrared spectroscopic (FT‐IR) and scanning electron microscopy (SEM).The effects of pH, ionic strength, temperature, porosity, particle size and levels of loaded drug on drug release profile in various surrounding media were investigated. Each sample was well characterized through swelling studies. The molecular weight between crosslinks $\displaystyle (\overline {{\tf="PS_HENI"M}}_C) $, crosslinking density (ve) polymer–solvent interaction parameter (χ), and the shear modulus of the superabsorbents (G) were calculated. The results revealed that the release profiles of IBU from the superabsorbent polymer were low (lower than 14%) in simulated gastric fluid (SGF, pH 1.2) over 3 h, but nearly all of the initial drug content (more than 79%) was released in simulated intestinal fluid (SIF, pH 7.4) within 6 h after changing media. Overall the results demonstrated that biodegradable superabsorbents could successfully deliver a drug to the intestine without losing the drug in the stomach, and could be potential candidates for an orally administrated drug delivery system.
Tectonics and petroleum potential of the East Arctic province
Authors: Khain V.E. , Polyakova I.D. , Filatova N.I. 
Published: March 2009

AbstractTectonics and petroleum potential of the underexplored East Arctic area have been investigated as part of an IPY (International Polar Year) project. The present-day scenery of the area began forming with opening of the Amerasia Ocean (Canada and Podvodnikov–Makarov Basins) in the Late Jurassic–Early Cretaceous and with Cretaceous–Cenozoic rifting related to spreading in the Eurasia Basin. The opening of oceans produced pull-apart and rift basins along continental slopes and shelves of the present-day Arctic fringing seas, which lie on a basement consisting of fragments of the Hyperborean craton and Early Paleozoic to Middle Cretaceous orogens. By analogy with basins of the Arctic and Atlantic passive margins, the Cretaceous–Cenozoic shelf and continental slope basins may be expected to have high petroleum potential, with oil and gas accumulations in their sediments and basement.
Studies on the Lime Requirements of Certain Soils
Authors: Hutchinson Henry Beougham , MacLennan Kenneth 
Published: March 2009

The experimental results described in the two parts of the paper may be summarised thus:Part I. Lime Requirements for Sterilisation Purposes.(1) The capacity to produce partial sterilisation effects is a property belonging to calcium oxide (caustic lime), but not to calcium carbonate (chalk, limestone, marl, etc.).(2) The amount of lime necessary to produce specific effects in different soils has been found to vary greatly and it is not possible to make any general recommendations.
The Influence on Crop and Soil of Manures applied to Permanent Meadow
Authors: Crowther Charles , Ruston Arthur G. 
Published: March 2009

The experiments reviewed in the preceding pages have been carried out on a light loam soil very poor in lime, in a district of medium rainfall (20–25 inches).The chief conclusions drawn from the results are as follows:1. Although the heaviest crops have been obtained with an annual application of dung, they are little heavier, and more costly to obtain, than the crops obtained with a biennial application of dung, especially if in the alternate year a light dressing of “artificials” including nitrate of soda be given.2. A complete mixture of “artificials,” including nitrate of soda, has given good average crops, but not equal to those given by a biennial application of dung.3. For the soil and other conditions of Garforth nitrate of soda is distinctly better for the hay crop than sulphate of ammonia. This is doubtless largely associated with the poverty of the soil in calcium carbonate.
The solubility of calcium phosphates in citric acid
Authors: Ramsay A. A. 
Published: March 2009

The results of these investigations show1. The substances sold as “Phosphate of lime” and “Calcium Phosphas B.P.” are not pure tricalcic phosphate but are mixtures of di- and tricalcic phosphates.2. Sodium phosphate (Na2HPO4) added to ammoniacal calcium chloride and the resulting precipitate washed with water yields a mixture of di- and tricalcic phosphate and calcium hydrate.3. Bone ash dissolved in hydrochloric acid and precipitated with ammonia, the precipitate being well washed, yields also a mixture of di- and tricalcium phosphate and calcium hydrate.4. When three equivalents of lime (3CaO) are made to act on one equivalent of phosphoric acid (P2O5) and the resulting precipitate removed with little delay pure tricalcium phosphate is obtained.
Critical note on the method of correcting protein digestion coefficients
Authors: Woodman Herbert Ernest 
Published: March 2009

The object of this note is to call into question the soundness of the generally accepted method by which the so-called apparent protein digestion coefficients of foodstuffs are corrected.The digestion coefficient for the protein of a foodstuff as ordinarily determined by animal experiment does not afford a strictly accurate idea of the actual digestibility of that constituent. The figure represents a minimum value, and this arises from the well-known fact that the faeces do not consist solely of undigested food residues, but are to an appreciable extent contaminated by nitrogenous products which have been secreted into the alimentary tract and have escaped reabsorption. The nature of this so-termed metabolic material is twofold, being partly protein (mucus, epithelium, etc.) and partly non-protein (residues of digestive secretions, etc.). Before proceeding to a critical survey of the correction method, which is designed ostensibly to enable allowance to be made for the presence of such products in the faeces, it is of essential interest to consider briefly the true significance of the term “protein digestibility.”
The Influence of size and character of seed on the yield of potatoes
Authors: Salaman Redcliffe N. 
Published: March 2009

The results of a preliminary investigation on this subject, in which single plots were used, which were published in 1921, tended to show that the following inferences, in respect to the relation of size and type of tuber-set to crop, might be drawn.1. The size of the crop varied directly with the weight of the set up to a certain point, viz. 2 ozs., the crop then sinking slightly to a more or less constant level, whilst the weight of the set increased.
The water content of the seeds of peas, soya beans, linseed, grass, onion and carrot as a function of temperature and humidity of the atmosphere
Authors: Gane R. 
Published: March 2009

SUMMARYMoisture content and temperature are of first importance in the storage of seeds. Seeds are usually stored in porous containers like sacks and paper bags, and their water content fluctuates with the humidity of the surrounding atmosphere. In sealed chambers, on the other hand, the humidity of the atmosphere will be determined by the water content of the seeds and, with different kinds of seeds in an enclosed space, an exchange of water will occur until equilibrium has been reached. This does not mean, however, that different kinds of seeds, or even different samples of the same kind will have exactly the same final water content, since the water content/humidity relations are affected by differences in structure, chemical composition and previous drying treatment; it is permissible, however, for practical purposes, to ignore the slight differences which occur between samples of the same kind of seed.