bluuebunny/crossref_metadata_2025 huggingface dataset:
Non‐destructive testing methods for determining the age‐hardening condition of aluminium alloys using the alloy EN AW‐6082 as an example
Authors: Grittner N. , Bormann D. , Springer R. , Reimche W. , Bach Fr.‐W.
Published: September 2010

Warmauslagerungsfähige Aluminiumlegierungen bieten den Vorteil, dass sie in ihrer Festigkeit in einem sehr weiten Bereich gezielt eingestellt werden können. Dies setzt voraus, dass die Prozesstemperaturen und ‐zeiten der Warmauslagerung sehr genau eingehalten werden. Die hier vorgestellten Arbeiten zielen auf die Qualifizierung zerstörungsfreier Messmethoden ab, mit denen der Warmauslagerungszustand Prozessbegleitend sehr schnell ermittelt werden kann. Somit können bereits während der Durchführung der Warmauslagerung Fehler im Prozess detektiert werden und im Sinne der Qualitätssicherung eine Verbesserung der Kontrollmechanismen erzielt werden. Die Untersuchungen wurden mittels Leitfähigkeits‐, Wirbelstrom‐ und Resonanz‐Frequenz‐Messungen durchgeführt. Insbesondere die Ergebnisse der Wirbelstrom‐ und Resonanz‐Frequenz‐Messungen lassen das hohe Potenzial zerstörungsfrei arbeitender Verfahren zur online Kontrolle des Warmauslagerungszustandes erkennen.

Heat treatable aluminium alloys offer the advantage that their strength can be specifically adjusted within a very broad range. This presupposes that the age‐hardening's process temperatures and durations are very precisely maintained. The work presented here aims to qualify non‐destructive testing methods with which the age‐hardening condition can be very rapidly determined during the actual process. Thus, process defects can be readily detected during the age‐hardening procedure and, within the scope of a quality assurance, an improvement of the control mechanisms can be obtained. The investigations were carried out by means of conductivity, eddy‐current and resonance‐frequency measurements. The results of the eddy‐current and resonance‐frequency measurements in particular allow the enormous potential of non‐destructive procedures to be realised for the online control of the age‐hardening condition.
Discussion of ‘Study on the action of the active earth pressure by variational limit equilibrium method’ by Li Xinggao and Liu Weining, International Journal for Numerical and Analytical Methods in Geomechanics 2010; 34:991–1008
Authors: Vahedifard Farshid
Published: September 2010

No Asbtract.
Analysis of early events in the interaction between Fusarium graminearum and the susceptible barley (Hordeum vulgare) cultivar Scarlett
Authors: Yang Fen , Jensen Jens D. , Svensson Birte , Jørgensen Hans J.L. , Collinge David B. , Finnie Christine
Published: September 2010

A proteomic analysis was conducted to map the events during the initial stages of the interaction between the fungal pathogen Fusarium graminearum and the susceptible barley cultivar Scarlett. Quantification of fungal DNA demonstrated a sharp increase in fungal biomass in barley spikelets at 3 days after inoculation. This coincided with the appearance of discrete F. graminearum‐induced proteolytic fragments of β‐amylase. Based on these results, analysis of grain proteome changes prior to extensive proteolysis enabled identification of barley proteins responding early to infection by the fungus. In total, the intensity of 51 protein spots was significantly changed in F. graminearum‐infected spikelets and all but one were identified. These included pathogenesis‐related proteins, proteins involved in energy metabolism, secondary metabolism and protein synthesis. A single fungal protein of unknown function was identified. Quantitative real‐time RT‐PCR analysis of selected genes showed a correlation between high gene expression and detection of the corresponding proteins. Fungal genes encoding alkaline protease and endothiapepsin were expressed during 1–3 days after inoculation, making them candidates for generation of the observed β‐amylase fragments. These fragments have potential to be developed as proteome‐level markers for fungal infection that are also informative about grain protein quality.
Prevalence of anxiety in patients awaiting diagnostic procedures in an oncology center in Brazil
Authors: Yu L. S. , Chojniak R. , Borba M. A. , Girão D. S. , Lourenço M. T. D. P. C.
Published: September 2010

Objective: Anxiety disorders have been shown to undermine the quality of life of cancer patients. Unfortunately, medical professionals often neglect to screen for anxiety in their patients. The aim of the present study was to describe the prevalence of anxiety in patients awaiting diagnostic procedures in an oncology center waiting room, and to investigate possible relationships between anxiety and demographic and clinical variables.

Methods: A cross‐sectional study was performed with 398 patients who completed a self‐administered questionnaire containing the Hospital Anxiety and Depression Scale (HADS) and the State‐Trait Anxiety Inventory (STAI).

Results: Results of the HADS indicated that 38% of participants had anxiety, while data from the STAI showed that 46% had either high state or trait anxiety. The most frequently cited source of anxiety was concern over test results. Age, gender, employment status, and education level were correlated with anxiety.

Conclusions: The prevalence of anxiety is high among patients awaiting diagnostic procedures. Patients in the waiting room should be routinely screened for anxiety. Careful assessment and treatment of anxiety are important components in the care of patients with cancer. Copyright © 2010 John Wiley & Sons, Ltd.
Effect of environment on ultrafast photoexcitation kinetics in single‐wall carbon nanotubes
Authors: Obraztsova Ekaterina A. , Lüer Larry , Obraztsova Elena D. , Chernov Alexander I. , Brida Daniele , Polli Dario , Lanzani Guglielmo
Published: September 2010

Recently, nonlinear optical properties of single‐wall carbon nanotubes (SWNT) have attracted a great interest. This material has been proven to be an efficient wide spectral range saturable absorber. However, up to now it is unclear what are the optimum sample preparation parameters and operational spectral range. In this work, we have applied femtosecond pump–probe spectroscopy to investigate photoexcitation kinetics in SWNTs depending on the sample preparation technique. We demonstrate here that the characteristic lifetimes of the saturable absorption in SWNT samples decrease with increasing interaction of SWNTs with each other and with the surrounding environment. We also show that the saturable absorption is fairly strong not only for the energies corresponding to the first electronic transition, but also for transitions at higher energies. We conjecture the contribution of energy and charge transfer to the observed ultrafast dynamics. Charge transfer is evidenced by a photo‐induced enhancement of the Sommerfeld factor.
Substrate reduction therapy with miglustat in chronic GM2 gangliosidosis type Sandhoff: results of a 3‐year follow‐up
Authors: Masciullo Marcella , Santoro Massimo , Modoni Anna , Ricci Enzo , Guitton Jerome , Tonali Pietro , Silvestri Gabriella
Published: September 2010

GM2 gangliosidosis type Sandhoff is caused by a defect of beta‐hexosaminidase, an enzyme involved in the catabolism of gangliosides. It has been proposed that substrate reduction therapy using N‐butyl‐deoxynojirimycin (miglustat) may delay neurological progression, at least in late‐onset forms of GM2 gangliosidosis. We report the results of a 3‐year treatment with miglustat (100 mg t.i.d) in a patient with chronic Sandhoff disease manifesting with an atypical, spinal muscular atrophy phenotype. The follow‐up included serial neurological examinations, blood tests, abdominal ultrasound, and neurophysiologic, cognitive, brain, and muscle MRI studies. We document some minor effects on neurological progression in chronic Sandhoff disease by miglustat treatment, confirming the necessity of phase II therapeutic trials including early‐stage patients in order to assess its putative efficacy in chronic Sandhoff disease.
Preaching the Gospel through Love of Neighbour: The Ministry of Katharina Schütz Zell
Authors: METHUEN CHARLOTTE
Published: September 2010

This article explores the ministry of service and love of neighbour exercised by Katharina Schutz Zell, wife of the Strasbourg Reformer Matthias Zell, focusing on Schutz Zell's theological justification for her ministry and her attempts to help those around her to understand their suffering in terms of the Gospel. Following Luther, Schutz Zell saw love of neighbour as an important means of spreading the Gospel, and thus as private activity, but as public ministry. Her work exemplifies, and may have served as a model for, the role of (female) deacon as defined by the Reformed tradition.
Monasticism and Reform in Book IV of Bede's ‘Ecclesiastical History of the English People’
Authors: DeGREGORIO SCOTT
Published: September 2010

The reform of the Northumbrian Church constitutes a predominant theme in much that Bede wrote in his later years. Recent analyses of his later biblical commentaries have confirmed this, although a tendency remains to treat his historiographic masterpiece, theEcclesiastical history of the English people, completed in c. 731, as only aloofly reformist in outlook. This article contests such a view through an analysis of the narrative and characters of book iv, which when scrutinised can be seen to amplify some of the key reform-oriented issues voiced in Bede's last and most openly reformist work, theLetter to Egbert.
Selection on ram 18-month weight to improve lamb growth rate
Authors: Croston D. , Read J. L. , Jones D. W. , Steane D. E. , Smith C.
Published: September 2010

Thirteen pairs of Suffolk rams were selected on high and low 18-month adjusted live weight from six farms over 2 years, to establish the relationship between 18-month weight and early lamb growth. Progeny were first produced in recorded crossbred flocks (618 lambs) and then in an experimental flock of crossbred ewes (1083 lambs). Different results were obtained from the recorded and experimental flocks. The regressions of lamb 12- to 13-week weight on ram 18-month weight (within farm deviation) were 0·053 ± 0·022 kg and –0·004 ± 0·020 kg, respectively. These regressions for indirect selection correspond to ‘effective’ heritabilities for direct selection for lamb growth of 0·18 ± 0·07 and 0·02 ± 0·06 respectively. Improvement of early Iamb growth is discussed and it is concluded that selection for 18-month weight is unlikely to be a useful method.
The effect of proportion of cell-wall material from lucerne leaf meal on apparent digestibility, rate of passage and gut characteristics in pigs
Authors: Kuan K. K. , Stanogias G. , Dunkin A. C.
Published: September 2010

Metabolism trials were conducted with entire male pigs (average initial weight 44·4 ± 0·2 kg) to determine the apparent digestibility of the major chemical components of diets containing 0·05, 0·10, 0·15 and 0·20 cell-wall material (determined as neutral detergent fibre) from lucerne leaf meal, when added to a constant daily allowance of a semi-synthetic basal diet. Concurrent rate of passage studies were also carried out.

Increasing the proportion of cell-wall material in the diet resulted in a linear decrease in the apparent digestibility of dry matter, crude protein and ether extract and the apparent digestibility and metabolizability of gross energy. Daily nitrogen retention (g) increased linearly with an increasing proportion of cell-wall material in the diet. Coefficients of apparent digestibility and cell-wall material fractions did not differ significantly with changes in the dietary proportions.

Although the rate of passage of digesta was slower (F < 0·001) in animals fed the diets containing 0·05 and 0·10 cell-wall material than in those fed the two diets with higher proportions, it did not appear to be a major factor contributing to the observed decline in the apparent digestibility of dietary chemical components as the proportion was raised.

Increase in dietary proportion of cell wall material was associated with marked linear increase in weight and/or length of various segments of the gastro-intestinal tract.
A preliminary study of the effects of the anthelmintic thiophanate (‘Nemafax’) on the breeding performance of sows naturally infested with Oesophagostomum spp
Authors: Baines D. M. , Lake P.
Published: September 2010

Three trials were conducted on commercial premises using sows naturally infested with gastro-intestinal nematodes, primarily Oesophagostomum spp. In two trials the farrowing performance of sows treated approximately 7 days before farrowing with thiophanate (‘Nemafax’) in-feed at a median dosage of 62·5 mg/kg was compared with that of untreated controls. In the third trial a similar comparison was made between sows treated approximately 7 days before expected service and untreated controls. In all cases faecal egg counts indicated thiophanate was highly effective against the nematode burdens present. Administered pre-farrowing, thiophanate resulted in better pre-weaning weight gains and relatively lower creep feed consumptions of the piglets. This effect was most marked in the trial with a higher level of Oesophagostomum spp. infestation in the sows. Under similar circumstances, pre-service medication produced a response in terms of live piglets born and those surviving to weaning.
A note on the carcass quality of Dairy Shorthorn, Red Friesian, Red Holstein, Danish Red, Meuse-Rhine-Yssel, Simmental and North Devon progeny of Dairy Shorthorn dams
Authors: Hocking P. M.
Published: September 2010

Carcass characteristics of 246 bulls and steers by Dairy Shorthorn (DS), Red Friesian (RF), Red Holstein (RH), Danish Red (DR), Meuse-Rhine-Yssel (MR), Simmental (SM) and North Devon (BB) bulls were recorded as part of a breed improvement programme. Carcasses of animals on grass-feeding systems were older, had lower fat and conformation scores and higher estimated lean yield than on intensive cereal systems, BB were fatter, and MR and SM leaner, than the remaining breed groups which were similar to DS and SM progeny had high conformation scores. Estimated lean in the live weight (g/kg) relative to DS was RF +5, RH −3, DR +5, MR +16, SM +16 and BB +6 with an average standard error of 3.
A note on the optimum level of roughage inclusion in the diet of the early-weaned calf
Authors: Thomas Delana B. , Hinks C. E.
Published: September 2010

Forty purchased male Hereford ♂ × Friesian ♀ calves (about 14 days old) were offered concentrate diets containing 0, 170, 230 or 320 g chopped (20 mm) straw per kg. Food intake and live-weight gains of calves were increased by the inclusion of straw, but the 320 g straw treatment tended to depress intake and gain. The optimum concentration of fibre for maximizing live-weight gains was 150 g trichloracetic acid fibre per kg of diet (220 g chopped straw per kg).
A note on the possible use of goats in hill sheep grazing systems
Authors: Russel A. J. F. , Maxwell T. J. , Bolton G. R. , Currie D. C. , White I. R.
Published: September 2010

A pilot study was conducted to investigate the possibility of using goats to manipulate the amount and composition of indigenous and improved vegetation on hill land in the west of Scotland.

Two vegetationally similar plots, each of approximately 0·6 ha, were used. Approximately 0·45 of each plot comprised sown ryegrass-clover pasture, the remainder being indigenous vegetation (principally Calluna vulgaris, Eriophorum and Tricophorum spp. with some Deschampsia, Molinia and Carex spp.). One plot was stocked with 14 yearling Anglo-Nubian goats and the other with seven mature Blackface sheep, the total weight of livestock on the two plots being the same (500 kg).

On the reseeded areas the proportions (± s.e. of difference) of ryegrass grazed by sheep and goats after 2, 5 and 8 weeks were 0·65 and 0·11 (0·075), 0·68 and 0·42 (0·112), and 0·77 and 0·58 (0·149), respectively; corresponding values for proportional clover cover were 016 and 0·45 (0·071), 0·16 and 0·38 (0·070), and 0·10 and 0·35 (0·070), respectively. The goats also actively grazed clumps of Juncus spp. and invading indigenous species which were not eaten by sheep.

On the indigenous areas the sheep grazed a higher proportion of Calluna than did goats (0·08 and 0·05) but grazed less E. vaginatum (0·07 and 0·13), E. angustifolium (0·04 and 0·11), and other indigenous species (0·21 and 0·36), respectively. The degree of utilization of grazed indigenous species by goats was also greater than that by sheep for all species except Calluna.

The results suggest that goats may have a use in some sheep production systems as an aid to the management of the varied plant communities of hill land, and particularly in the maintenance and further improvement of reseeded pastures.
Climatological features of cutoff low systems in the Southern Hemisphere
Authors: Reboita Michelle Simões , Nieto Raquel , Gimeno Luis , da Rocha Rosmeri Porfírio , Ambrizzi Tércio , Garreaud Rene , Krüger Luiz Fernando
Published: September 2010

Cutoff lows (COLs) pressure systems climatology for the Southern Hemisphere (SH), between 10°S and 50°S, using the National Center for Environmental Prediction–National Center for Atmospheric Research (NCEP‐NCAR) and the ERA‐40 European Centre for Medium Range Weather Forecast (ECMWF) reanalyses are analyzed for the period 1979–1999. COLs were identified at three pressure levels (200, 300, and 500 hPa) using an objective method that considers the main physical characteristics of the conceptual model of COLs. Independently of the pressure level analyzed, the climatology from the ERA‐40 reanalysis has more COLs systems than the NCEP‐NCAR. However, both reanalyses present a large frequency of COLs at 300 hPa, followed by 500 and 200 hPa. The seasonality of COLs differs at each pressure level, but it is similar between the reanalyses. COLs are more frequent during summer, autumn, and winter at 200, 300, and 500 hPa, respectively. At these levels, they tend to occur around the continents, preferentially from southeastern Australia to New Zealand, the south of South America, and the south of Africa. To study the COLs at 200 and 300 hPa from a regional perspective, the SH was divided in three regions: Australia–New Zealand (60°E–130°W), South America (130°W–20°W), and southern Africa (20°W–60°E). The common COLs features in these sectors for both reanalyses are a short lifetime (∼80.0% and ∼70.0% of COLs at 200 and 300 hPa, respectively, persisting for up to 3 days), mobility (∼70.0% and ∼50% of COLs at 200 and 300 hPa, respectively, traveling distances of up to 1200 km), and an eastward propagation.
First observation‐based estimates of cloud‐free aerosol radiative forcing across China
Authors: Li Zhanqing , Lee Kwon‐Ho , Wang Yuesi , Xin Jinyuan , Hao Wei‐Min
Published: September 2010

Heavy loading of aerosols in China is widely known, but little is known about their impact on regional radiation budgets, which is often expressed as aerosol radiative forcing (ARF). Cloud‐free direct ARF has either been estimated by models across the region or determined at a handful of locations with aerosol and/or radiation measurements. In this study, ARF is determined at 25 stations distributed across China where aerosol optical thickness has been measured since 2004. In combination with the single‐scattering albedo retrieved from ground and satellite measurements, ARF was determined at all the stations at the surface, inside the atmosphere, and at the top of atmosphere (TOA). Nationwide annual and diurnal mean ARF is found to be −15.7 ± 8.9 at the surface, 0.3 ± 1.6 at the TOA, and 16.0 ± 9.2 W m−2 inside the atmosphere. These values imply that aerosols have very little impact on the atmosphere‐surface system but substantially warm up the atmosphere at the expense of cooling the surface. The strong atmospheric absorption is likely to alter atmospheric thermodynamic conditions and thus affects circulation considerably.
Calculations of the binding affinities of protein-protein complexes with the fast multipole method
Authors: Kim Bongkeun , Song Jiming , Song Xueyu
Published: September 2010

In this paper, we used a coarse-grained model at the residue level to calculate the binding free energies of three protein-protein complexes. General formulations to calculate the electrostatic binding free energy and the van der Waals free energy are presented by solving linearized Poisson–Boltzmann equations using the boundary element method in combination with the fast multipole method. The residue level model with the fast multipole method allows us to efficiently investigate how the mutations on the active site of the protein-protein interface affect the changes in binding affinities of protein complexes. Good correlations between the calculated results and the experimental ones indicate that our model can capture the dominant contributions to the protein-protein interactions. At the same time, additional effects on protein binding due to atomic details are also discussed in the context of the limitations of such a coarse-grained model.
Growth and photoresponse study of PdO nanoflakes reactive-sputter deposited on SiO2
Authors: Huang Chien-Jung , Pan Fu-Ming , Chen Hsiu-Ying , Li-Chang
Published: September 2010

This study prepares PdO nanostructures on a SiO2 substrate by reactive-sputter deposition and examines photoresponse characteristics of the thin films. PdO thin films deposited at 25 °C is composed of bowed nanoflakes standing on the SiO2 substrate, which have a single-crystalline structure after thermal anneal at 400 °C. The 400 °C-annealed nanoflake thin film has a band gap energy in the red-light range (∼2.06 eV), and exhibits a very sensitive photoresponse upon the UV (365 nm) illumination. The high photoresponse sensitivity of the 400 °C-annealed nanoflake thin film is ascribed to a lower density of recombination centers and traps due to an excellent crystallinity and a high carrier extraction efficiency due to a low electrical resistivity. A slight decrease in the photocurrent density during the initial stage of the UV illumination is attributed to adsorption of O2− anions on the 400 °C-annealed nanoflakes.
Micromechanical prediction of the effective electromechanical properties of cellular ferroelectrets
Authors: Wan Yongping , Xie Longtao , Zhong Zheng
Published: September 2010

Cellular space-charge foams, which have very sensitive transducer properties and are called cellular ferroelectrets, emerged as a kind of novel electromechanical transducer materials. In recent years, the understanding of charging is advanced significantly. However, some fundamental theoretical aspects, as to the relation between the electromechanical behavior and their mesostructures, are still far from clear. As is well known, the transducer coefficients in the thickness direction strongly depend on the relative density of foam, which is essentially relevant to the mesostructure, such as void shape, void fraction, etc. In this article, a theoretical model based on micromechanics is proposed to estimate the overall electromechanical moduli of cellular ferroelectrets. From the viewpoint of composites, in this model, the voids with surplus charge are deemed as heterogeneous inclusions, which show piezoelectriclike effect under deformation. The matrix is the nonpolar polymer. Within the micromechanical framework for piezoelectric composites, the generalized Eshelby tensor is obtained for both isotropic and anisotropic matrix. The equivalent inclusion method is employed to treat inhomogeneities. Similar to the classical differential scheme for pure elasticity, the differential equation for the effective electromechanical moduli is derived, from which the overall behavior of cellular space-charge foam can be numerically solved. Detailed analysis is presented with respect to material parameters and geometrical variables of void. Finally, this model is used to simulate the inflation experiments of cellular ferroelectret film published in literature. Results show this model is capable of predicting the extremum of the effective electromechanical moduli. In the meantime, quantitative comparison indicates that theoretical simulation is in good consistency with experiment data.
Low temperature deformation of the R-phase in a NiTiFe shape memory alloy
Authors: Krishnan V. B. , Shmalo S. B. , Rathod C. R. , Bourke M. A. M. , Vaidyanathan R.
Published: September 2010

Deformation in the P3 phase (R-phase) of NiTiFe was investigated by in situ neutron diffraction during compressive loading at cryogenic temperatures. At 216 K, upon loading the R-phase detwinned and subsequently underwent a reversible stress-induced transformation to the B19′ phase (martensite). At 92 K on the other hand, detwinning was suppressed and the stress-induced martensite formed did not transform back upon unloading. The experiments also directly observed a hitherto theoretically predicted B33 phase. Rietveld refinement of the neutron diffraction spectra were used to determine lattice parameters of the B33 and R-phases. Plane-specific elastic moduli were also determined for the R-phase.
Electro-optic polymer infiltrated silicon photonic crystal slot waveguide modulator with 23 dB slow light enhancement
Authors: Lin Che-Yun , Wang Xiaolong , Chakravarty Swapnajit , Lee Beom Suk , Lai Weicheng , Luo Jingdong , Jen Alex K.-Y. , Chen Ray T.
Published: September 2010

A silicon/organic hybrid modulator integrating photonic crystal (PC) waveguide, 75 nm slot, and electro-optic (EO) polymer is experimentally demonstrated. Slow light in PC waveguide and strong field confinement in slot waveguide enable ultraefficient EO modulation with a record-low Vπ×L of 0.56 V mm and an in-device effective r33 of 132 pm/V. This result makes it the most efficient EO polymer modulator demonstrated to date. The modulated signal shows strong wavelength dependence and peak enhancement of 23 dB near the band edge of defect mode, which confirms the signature of the slow light effect.
An Exciton Approach to the Excited States of Two Electron Atoms. II. Determination of Spectroscopic Parameters, Polarizabilities and Dispersion Coefficients of H-, He, Li+, Be2+ and Ne8+
Authors: Schipper PE , Martire B
Published: September 2010

The exciton model developed in an earlier paper is applied quantitatively to a description of the excited states of representative members of the helium isoelectronic series; viz. H-, He, Li+,Be2+ and Ne8+. The energies of the eight lowest excited states are in good agreement with experiment, for a relatively small (1s-4p) hydrogenic basis; the ground state is obtained with slightly less precision. Response properties including oscillator strengths, polarizabilities and dispersion interaction coefficients are also calculated. The method appears to be quantitatively sound, and, above all, leads to particularly simple interpretations of the wave functions and the energies.
reactions of 2-t-Butyl-4,6-dimethylphenol, 2,4-Di-t-butyl-6-methylphenol and 2,4,6-Tri-t-butylphenol with Nitrogen Dioxide
Authors: Hartshorn MP , Robinson WT , Sutton KH , Vaughan J
Published: September 2010

Reaction of 2-t-butyl-4,6-dimethylphenol(10) with nitrogen dioxide in benzene gives the C4-epimeric 4,5,6-trinitrocyclohex-2-enones (13) and (14). In contrast, similar reaction of 2,4-di-t-butyl-6-methyl-phenol (11) gives substituted cyclohex-3-enones, 2,5,6-trinitro ketones (20)- (23), 2-hydroxy-5,6-dinitro ketones (27) and (28) and the 6-hydroxy- 2,5-dinitro ketone (29). Reaction of
2,4,6-tri-t-butylphenol (12) with nitrogen dioxide gives initially the 4-nitro dienone (35), but de-t- butylated products (36) and (37) are formed in long-term reactions. X- ray crystal structures are reported for compounds (13),(14),(21),(22), (23), (27), (28) and
(29).
Lewis-Base Adducts of Group 1B Metal(I) Compounds. XX. Synthesis, Spectroscopic and Structual Studies of Acetonitrile-Solvated Triphenylphosphine-Copper(I) Perchlorate Adducts
Authors: Barron PF , Dyason JC , Engelhardt LM , Healy PC , White AH
Published: September 2010

The compounds, [(PPh3)4Cu] ClO4, (I), [(CH3CN)( PPh3)2 Cu] ClO4, (2), and [(CH3CN)2(PPh3)2Cu]-ClO4, (3) ( PPh3 = triphenylphosphine ), have been characterized by solid-state 31P n.m.r . spectroscopy and crystal structure analysis. Crystals of (2) are orthorhombic, Pcab , a 24.506(9), b 22.49(1), c 17.905(8) Ǻ, Z = 8; R was 0.089 for 2178 independent 'observed' reflections. Crystals of (3) are monoclinic, P21/n, a 15.506(6), b 26.98(1), c 9.220(3) Ǻ, β 94.70(3)°, Z = 4; R was 0.070 for 2622 independent reflections. In both cations, the copper(:) atom is four-coordinate by the phosphine and acetonitrile ligands . In (2), Cu-P are 2.321(5)-2.338(5) Ǻ, with Cu-N, 2.11(1) Ǻ; N-Cu-P lie between 100.1(3) and 106.0(3)°, while P-Cu-P range from 113.0(2) to 119.3(2)°. In (3), Cu-P are 2.257(3), 2.278(3) and Cu-N, 2.068(8) and 2.020(8) Ǻ; with P-Cu-P, 127.6(1), N-Cu-N, 99.2(3), and P-Cu-N, 101.7(2)-109.9(3)°. Solid state 31P n.m.r . spectra of (1), (2) and (3) show one, three and two sets of overlapping quartets respectively. The average chemical shift data for each quartet with respect to 85% phosphoric acid is: (1)-5.0ppm; (2)2.6, 1.2, -0.6 ppm ; (3) 4.0,-3.0 ppm [cf. free PPh3 in the solid state, -9.9 ppm ]. The magnitude, Δvi, and asymmetry, Avvij, of the splitting between the peaks of each quartet is consistent with a distorted tetrahedral environment for the three compounds. Infrared spectroscopic, differential scanning calorimetric, solid state 31P n.m.r . and powder XRD measurements show that heating of (2) and (3) leads to the desolvated complexes, [(PPh3)3CuClO4], (4), and [(PPh3)2CuClO4], (5), in which the perchlorate anions function as monodentate and bidentate ligands respectively.
Properties of CdTe Films Heat-Treated in Te Vapour
Authors: Winn MB , Lyons LE
Published: September 2010

Upon heat treatment in Te vapour , CdTe films formed by compound evaporation showed a decrease in resistivity of four orders, while an increase in grain size was detected by SEM and XRD. The diffusion length, Hall mobility, lifetime and density of holes in as-deposited films was determined from the PME effect. XRD and XPS detected no free Te in films before or after heat-treatment, while SIMS indicated the inclusion of at least 16 impurities from the source material. CdS/CdTe photovoltaic cells based upon these films showed an increase in efficiency of one order.
The Basicity of 2,6-Dimethyl-4-pyrone
Authors: Farrell JR , Mctigue P
Published: September 2010

Conductimetric and spectrophotometric measurements of the Ka of protonated 2,6-dimethyl-4-pyrone have been made. The conductimetrically determined value of pKa = 0.17�0.03 was 0.2 pK units higher than the value of pKa = -0.02�0.05 found spectrophotometrically . The spectrophotometric studies in concentrated sulfuric and hydrochloric acids revealed that, at low acid concentrations, the pyrone had an excess acidity slope parameter (m‡) of -0.29. However, over a large acid concentration range, m‡ was observed to vary in a way that caused moderate systematic errors in the excess acidity extrapolation procedure. For this reason the conductimetric value is considered more reliable.
The Reaction of 3-Oxoolean-12-en-29-oic Acid with Acetic Anhydride-Perchloric Acid
Authors: Gaul KL , Lewis KG , Skelton BW , White AH
Published: September 2010

Reaction of acetic anhydride- perchloric acid with 3-oxoolean-12-en-29- oic acid (4) gave either the enol acetate (6) or the derived γ- pyrono compound (8). The structure assigned to the latter was confirmed by a single-crystal X-ray structure determination. Comment is made on doubts about this reaction as a method of structure assignment.
N.M.R. Spectra of the Β-Methylcinnamic Acids and their Methyl Esters
Authors: Shoppee CW , Brownlee RTC
Published: September 2010

The configurations of the (E)- and (Z)-β- methylcinnamic acids and their methyl esters have been confirmed by 1H and 13C n.m.r . spectroscopy.
Stabilities of Carbonium-Ions. IV. Steric Effects in the Solvolysis of Substituted Diphenylmethyl Chlorides
Authors: Bolton R , Burley RE , Williams NJ
Published: September 2010

The replacement of ortho-hydrogen atoms by methyl groups in diphenylmethyl chloride has three distinguishable results upon the rate of solvolysis . Firstly, the alkyl groupactivates by its electronic effect; secondly, steric interactions diminish all observed substituent effects regardless of the position of the substituent in the aryl system; and thirdly, steric acceleration of the solvolysis can be seen in the rate of reaction of bis (2,6-dimethylphenyl)methyl chloride. The ortho-methyl substituents inhibit the formation of the planar transition state necessary to allow the greatest resonance stabilization by the aryl substituents of the incipient carbocation. Greater degrees of twist are reflected both in the variations in the rates of solvolysis of the poly(orthomethyl ) diphenylmethyl chlorides and in the consistent fall in the value of p+ with successive ortho-substitution.
Vibrational-Spectra of Salts of the Type-AI3[Mo2X9] with X = Cl, Br, I
Authors: Smith PW , Stranger R
Published: September 2010

The far-infrared and Raman spectra of a series of alkali, ammonium and alkylammonium salts of Mo2X93- (X = Cl , Br, I) have been measured. All observed infrared-active vibrations, including lattice modes, together with certain Raman-active modes, have been assigned for the alkali salts of Mo2Cl93- on the basis of the D6h unit cell symmetry which applies. The vibrational assignments for the corresponding bromide and iodide complexes follow in the same relative order as those of Mo2Cl93-. The splitting of degenerate modes for certain alkylammonium salts of Mo2Cl93- has been interpreted on the basis of C2v symmetry applicable to these particular salts. By correlating the spectral changes observed with variation of the cation, it has been possible to distinguish the bridging-halogen deformation modes from neighbouring lattice modes.
Halogenated Terpenoids. XXV. The Structure of Limonene Tetrabromide
Authors: Carman RM , Kennard CHL , Robinson WT , Smith G , Venzke BN
Published: September 2010

X-ray crystallography has been used to confirm that the structure of crystalline limonene tetrabromide, derived from (+)-limonene, has the 8R configuration and is therefore (1S,2S,4R,8R)-1,2,8,9-tetrabromo-p- methane. By using the same method, racemic limonene dibromodichloride [1RS,2RS,4SR,8SR)-8,9-dibromo-1,2-dichloro-p-methane] has been shown to have the same configuration.
The Chemistry of Pyrrolic Compounds. LX. Reaction of Photoprotoporphyrin-IX Dimethyl Ester With Cyanide Ion
Authors: Clezy PS , Tonkin K
Published: September 2010

Reaction of the a,β-unsaturated aldehyde system of photoprotoporphyrin IX dimethyl ester with cyanide ion yields a porphyrin with an acetamide side chain. Mechanistically, the reaction can be viewed as an intramolecular hydrolysis of the cyanide adduct driven by a return to a macrocycle with the porphyrin conjugation pathway.
Platinum Silicide/n-Silicon Photoelectrodes: Properties and Characteristics of the Platinum Silicide Layer
Authors: Hope GA , Pham DK
Published: September 2010

The surface analysis of thermally grown platinum silicide layers on single crystal silicon wafers has shown that silicide phase growth can occur for thin films. The depth profile was found to depend upon the temperature at which the silicide was formed, the length of time for which the reaction proceeded and the supply of platinum. The ESCA peaks for Pt and Si were shifted in energy from the elemental values in the silicide layer. A surface oxide, assigned as SiO2 from the Si 2p signal, was detected on all samples. The platinum signal broadened considerably when the silicide layer had been largely removed by sputtering, and appeared to consist of two components.
The Stereochemistry of SRN1 Reactions in Nitroacenaphthenes
Authors: McLure FI , Norris RK
Published: September 2010

The reaction of the 2-chloro-1,l-dialkyl-6-nitroacenaphthenes (1)-(3) with azide and p- toluenethiolate ions takes place by the SRN1 mechanism, to give the substitution products (27)-(32), despite the fact that the nitro group and the chlorine-bearing benzylic carbon are attached to different aromatic rings. The reaction of the stereoisomers (2) and (3) of 2-chloro-1-ethyl-1-methyl-6-nitroacenaphthene takes place through an effectively planar benzylic radical (35), which is preferentially attacked from the face remote from the a-ethyl group. The presence of geminal alkyl groups α to the reaction site in the rigid acenaphthene system restricts the scope of the substitution processes to sterically unhindered nucleophiles, and the reaction fails with reagents such as sodium p- toluenesulfinate (23) and the salts, (24) and (25), derived from 2-ethylmalononitrile and 2-nitropropane.
Characterization, Redox Properties and Pulse-Radiolysis Study of Dichloro-(Tetraazacyclotetradecane)Manganese(III) Complexes, and X-Ray Crystal-Structure of the meso-5,7,7,12,14,14-Hexamethyl-1,4,8,11-Tetraazacyclotetradecane Complex
Authors: Hambley TW , Lawrance GA , Sangster DF , Ward CB
Published: September 2010

The complexes [Mn ( mac )Cl2]+ [ mac = 1,4,8,1l-tetraazacyclotetradecane (cyclam), meso and rac-5,7,7,12,14,14-hexamethylcyclam ( teta and tetb respectively)] have been prepared. The trans-[ Mn ( teta )Cl2] Cl.3H2O complex crystallizes in the monoclinic space group P21 /c, Z 2, a 8.4006(8), b 12.465(2), c 11 .659(2) �, β 103.20(1)�. The geometry about the manganese(III) is close to octahedral with the macrocycle coordinated to four equatorial sites ( Mn -N 2.043(2), 2.074(2) �) and chlorides in trans axial sites (Mn -Cl 2.549(1) �. Since electronic spectra of the cyclam and teta complexes are similar, the ions should exist in similar geometries; however, the tet b analogue is spectroscopically unique, and the complex may adopt a different geometry. All complexes in water exhibit quasi-reversible one-electron couples near O V at a mercury electrode; irreversible reductions of manganese(II) are also observed before the solvent limit near -1.5 V for the teta and tet b complexes. No metal-centred oxidation waves are seen before the solvent limit (c.+ 1 V) at a platinum electrode. However, pulse radiolytic oxidation (with OH) of all complexes is observed with formation kf > 109 dm3mol-1 s-1; apparently d3 manganese(IV) monomers with electronic spectra qualitatively similar to d3 chromium(III) complexes are formed. Decay of these intermediates is first-order, with all kd ≥ 5×103 s-1, but varying with the macrocyclic ligand present. Alkyl substitution on the cyclam stabilizes the manganese(IV) oxidation state, the intermediate cyclam complex decaying 25 times faster than the teta analogue. The final decay product appears to be MnO2, and rate-determining ligand loss is presumed.
The Structure of the Novel Lichen Xanthone Thiomelin and Its Cogenors
Authors: Elix JA , Gaul KL , Sterns M , Binsamsudin MW
Published: September 2010

The structure determination of thiomelin (2,4-dichloro-1,8-dihydroxy-5-methoxy-6-methyl-9H-xanthen-9-one) (3), an unusual lichen metabolite probably derived biosynthetically by oxidative ring opening of a precursor anthraquinone, is reported. The crystal structure of thiomelin diacetate (4) was determined by X-ray diffraction, while that of the cogenors 8-O-methylthiomelin (5), 4-dechlorothiomelin (7), 4-dechloro-8- O- methylthiomelin (9), 2-dechloro-8- O- methylthiomelin (10) and 2,4-dichloro-l-hydroxy-7-methoxy-6,8-dimethyl-9H-xanthen-9-one (12) were deduced from spectroscopic data.
Thermal Decomposition of Some Iron(III) Chromates
Authors: Mineely PJ
Published: September 2010

The thermal decomposition of the chromates FeOHCrO4, KFe3(CrO4)2(OH)6, Fe2(CrO4)3.H2O and Fe2(CrO4)3.3H2O have been studied by thermal analysis and Mossbauer spectroscopy. The possible presence of Fe2O(CrO4)2 as a second phase formed during the decomposition is discussed. Final products in all reactions were oxides of iron(III) and chromium(III). In addition K2Cr2O7 Was present in the reaction products for KFe3(CrO4)2(OH)6.
Concentration Oscillations During Diffusion With Slow First-Order Chemical Reaction in Aqueous Solutions of trans-Dichloro-bis(ethane-1,2-diamine)cobalt(III) Chloride, trans-[Co(en)2Cl2]Cl
Authors: Leaist DG
Published: September 2010

The rate equations for diffusion and chemical reaction have been solved for isothermal diffusion with the first-order reactionA → Bin stirred diaphragm cells. Provided pseudo-steady-state conditions are established in the diaphragms, the concentration differences across the diaphragm for the reactant and product are predicted to show damped oscillations in time for certain values of the solute diffusivities. Diffusion coefficients have been determined for aqueous solutions of trans-dichlorobis (ethane-1,2-diamine)cobalt(III) chloride in which the 1 : 1 salt slowly converts into a 1:2 salt through the reaction [Co(en)2Cl2]+ + Cl - → [Co(en)2Cl]2+ +2Cl- with k = 3.6×10-5 s-1 at 25°C. Supplementary ternary diffusion coefficients have been determined for aqueous solutions of potassium acetate + potassium sulfate, a ternary mixed electrolyte with ionic mobilities similar to those of the aqueous cobalt salts.
Dihedral Angles of the Cycloheptane Ring
Authors: Bottomley GA
Published: September 2010

A method is described for calculating sets of dihedral angles in a seven- membered ring with equal tetrahedral bond angles and equal bond lengths. Representative values are given for the separate chair and boat manifolds of solutions.
Radial Functions of CH+ in the Electronic State a 1Π
Authors: Ogilvie JF
Published: September 2010

From published data of the spectral parameters of 12C1H+ and 12C2H+ in the A 1Π electronic state, the dependences on internuclear separation R of the internuclear potential energy, the adiabatic and non-adiabatic contributions to the molecular energy, and the interaction of the electronic orbital and rotational angular momenta have been derived, all applicable within the range 0.99 < R/10-10 m < 1.90.
Sesquiterpenes From a New Zealand Sponge of the Genus Eurypon
Authors: Barrow CJ , Blunt JW , Munro MHG
Published: September 2010

A cytotoxic sesquiterpene (1) with a tricyclo [6.3.1.0.2,5] dodecane skeleton has been isolated from the extract of a New Zealand Eurypon sp. of sponge. Two derivatives, (2) and (3), of this sesquiterpene have also been isolated, probably as artefacts arising during the isolation procedure. The structure of a spiro sesquiterpene (4), also obtained from the sponge extract, has been determined. Previously published n.m.r. assignments for β-caryophyllene alcohol (5) have been revised.
Conformational Energy Calculations on the Eosinophil Chemotactic Peptide Analog Val-Gly-Ala-Glu: Comparison of Theory and Experiment
Authors: Bremer J , Mendz GL
Published: September 2010

Conformational energy calculations have been employed to obtain minimum energy conformations of the peptide Val- Gly-Ala-Glu , an analogue of eosinophil chemotactic tetrapeptides. The calculated conformations of the peptide can be described as an ensemble of structures in which the C-terminal and N-terminal regions of the molecule are in close proximity. The charge state of the peptide showed a marked effect on the calculated conformation, and the results were also sensitive to the electrostatic environment. The calculations performed on the dianionic form of the molecule showed good agreement with experimental n.m.r . Data on coupling constants, amide-proton resonance chemical shifts and temperature coefficients, nuclear Overhauser effects, side-chain rotamer populations, and binding of paramagnetic ions, obtained in dimethyl sulfoxide solutions. The calculations demonstrate some of the inherent problems facing theoretical calculations of peptide structure.
Cementation of Lead From Lead Sulfate Slurries. III. Kinetics and Reaction Mechanisms With Iron Precipitant
Authors: Bear IJ , Flann RCA , Woods R , Gardner JR
Published: September 2010

The cementation of lead from lead sulfate powders with iron metal precipitant has been studied in stirred aqueous slurries. The kinetics followed two alternative regimes analogous to those observed previously for the lead sulfate/zinc system. Kinetic regime No. 1 was characterized by an initial fast reaction and a subsequent period of stagnation or even apparent reversal. For this regime, the percentage yield for constant reaction period increased with decrease in the initial partial pulp density (IPPD) of lead sulfate. With regime No. 2, the initial reaction was slower but the reaction continued to completion at a steady rate. Also, the percentage yield for constant reaction period increased with increase in IPPD of lead sulfate. Two mechanisms (Mech. 1 and Mech. 2) corresponding to the two kinetic regimes are proposed to explain the observed kinetics and these mechanisms operate in the same way as they do for the lead sulfate/zinc system. However, the particle size/surface area of the iron was found to be the important parameter in determining which mechanism controlled the reaction, whereas it was the effective particle size/surface area of the lead sulfate when zinc was the precipitant. For the same iron powder, control of the reaction can be transferred from Mech. 1 to Mech. 2 by commencing the slurry cementation in ferrous sulfate solution rather than water. Comment is made concerning the use of iron precipitant in a commercial operation.
Lewis-Base Adducts of Main Group-1 Metal-Compounds. VIII. Synthesis and Structural Characterization of 1-2 and 1-3 Adducts of Lithium-Nitrate With Monodentate Nitrogen Bases
Authors: Raston CL , Whitaker CR , White AH
Published: September 2010

Crystallization of lithium(I) nitrate from 2-methylpyridine and 3,5-dimethylpyridine yields 1 : 2 and 1:3 adducts respectively, characterized by single-crystal X-ray structure determination. The 1:2 adduct is a linear polymeric species with the lithium atom four- coordinated by two monodentate ligands and two oxygen atoms of O,O′- bridging nitrate groups; there are two crystallographically independent polymeric strands in the structure. The 1:3 adduct is mononuclear, again with four-coordinate lithium. The three Li-N distances range from 2.05(2) to 2.08(2)Ǻ, while Li-O is 1.98(2)Ǻ.
Lewis-Base Adducts of Group 11 Metal(I) Compounds. XLI. Conformational Systematics of [(N-base)1(CuX)1]∞ 'Skewed Stair' Polymers [N-base = (Substituted) Pyridine]
Authors: Healy PC , Kildea JD , Skelton BW , White AH
Published: September 2010

In contrast to the symmetrical 'orthogonal' 'stair' polymers recorded in the previous paper, a
variety of distorted ('skewed') stair polymer systems have been synthesized and structurally characterized by using substituted pyridine bases. The structure of CuBr/pyridine (1 : 1) is recorded, completing the series for pyridine with all halides (CI, Br, I), together with full halide arrays for the bases pyridine-2-carbaldehyde and 4-benzoylpyridine, in which substituent interactions with metal or halide are insufficient to destroy the basic polymer form but nevertheless may induce substantial distortions from the orthogonal ideal.
Lewis-Base Adducts of Group 11 Metal(I) Compounds. XLIV. Synthesis and Conformational Systematics of 1 : 1 Copper(I) Halide Nitrogen Base Adducts as [(N-base)CuX2Cu(N-base)] Dimers (X = Cl, Br, I) and [(N-Base)CuX] Monomers (X = Cl, Br)
Authors: Healy PC , Kildea JD , White AH
Published: September 2010

A complete array of [LcuX2CuL] dimers for the system CuX/monodentate nitrogen base, L, all X = Cl, Br, I, has been synthesized and structurally characterized for the highly hindered pyridine base L ≈ 1,2,3,4,5,6,7,8-octahydroacridine, enabling comparison of stereochemical parameters with previously characterized [L2CuX2CuL2] arrays (L monodentate ). With L-2,2,6,6-tetramethylpiperidine, a similar dimer is also obtained with copper(I) iodide, but with the chloride and bromide adducts linear monomers [ LCuX ] have been obtained, the first to be structurally characterized for the copper(I) halide/nitrogen base system. In the latter Cu-Cl, Br are 2.087(2) and 2.216(2), 2.202(2) A, Cu-N being 1.923(3) and 1.931(9), 1.9337) � .