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111.
112.
A. Boyle J. F. Penneau E. Genis C. Riekel 《Journal of Polymer Science.Polymer Physics》1992,30(3):265-274
The effect of heating on four chemically synthesized polyanilines, three of which were doped by HCI, H2SO4, HCIO4, and one sample which was dedoped, was investigated. The structural variations during thermal decomposition were studied by real-time synchrotron radiation diffractometry and correlated with mass spectrometry (MS), thermal gravimetry (TG), and differential thermal analysis (DTA). These macroscopic and microscopic techniques were combined in order to shed more light on the role played by the water and the counteranion molecules on the structure of doped polyaniline. Evidence for two H2O fractions was found for HCI-doped polyaniline. Chain degradation was observed for HCIO4 and H2SO4-doped polyaniline. The results indicate that intermediate sulphonation of polymer chains occurs in the latter case. 相似文献
113.
An orthonormal set of irreducible fifth-rank tensors having the required permutation symmetry is constructed. Various problems not encountered in the analogous problem for tensors of ranks two, three, four and six are discussed. 相似文献
114.
L. L. Boyle 《International journal of quantum chemistry》1972,6(4):725-746
Tables of symmetrized powers of the irreducible representations of point groups are presented together with a derivation of the formula used to obtain them. It is shown how these tables may be applied to various quantum-chemical problems. 相似文献
115.
Perpendicularly orientated ZnO rods have been grown on thin ZnO templates, from aqueous solutions of zinc acetate and hexamethylenetetraamine (HMT); growth along the c-axis of the ZnO crystallites is promoted by the presence of acetate in the bath. 相似文献
116.
Yuen Ping Tan Kylie A. Agnew-Francis Julian Hofmann Dr. Andrei I. Savchenko Dr. Scott R. Lafontaine Prof. Glen M. Boyle Prof. Paul V. Bernhardt Prof. James A. Fraser Prof. Thomas H. Shellhammer Prof. Craig M. Williams 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(7):1653-1660
Dysphania is an abundant genus of plants, many of which are endemic to the Australian continent, occurring primarily in arid and temperate zones. Despite their prevalence, very few investigations into the phytochemistry of native Dysphania have been undertaken. Described herein, is the isolation and elucidation of two enantiomeric diastereomers of humulene diepoxide C from D. kalpari and D. rhadinostachya, of which unassigned diastereomers of humulene diepoxide C have been previously reported as components in beer brewed from aged hops. In addition, two (+)-humulene diepoxiols (humulene diepoxiol C-I and C-II) were isolated from D. rhadinostachya. Analysis of Chinook hops oil confirmed the presence of both humulene diepoxide C-I and C-II as trace components, and in turn enabled GC-MS peak assignment to the relative stereochemistry. Anticancer assays did not reveal any significant activity for the (+)-humulene diepoxides. Antifungal assays showed good activity against a drug-resistant strain of C. auris, with MIC50 values of 8.53 and 4.91 μm obtained for (+)-humulene diepoxide C-I and C-II, respectively. 相似文献
117.
Gold‐Catalyzed Sequential Cyclization of 1‐En‐3,9‐Diyne Esters to Partially Hydrogenated 3H‐Dicyclopenta[a,b]naphthalenes 下载免费PDF全文
Prof. Dr. Weidong Rao Joshua William Boyle Prof. Dr. Philip Wai Hong Chan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(19):6532-6536
A synthetic method that relies on a gold(I)‐catalyzed cycloisomerization of 1‐en‐3,9‐diyne esters to spiro[4.4]non‐2‐ene‐substituted 1,2‐dihydronaphthalenes is described. Robust with a wide variety of substitution patterns tolerated, the reaction provides the first example of a one‐step strategy to construct such novel and architecturally challenging members of the carbocycle family in good to excellent yields. A mechanism is proposed in which the sequential cycloisomerization pathway was thought to involve a gold‐catalyzed 1,3‐acyloxy migration/Nazarov cyclization followed by a formal [4+2] cycloaddition to give the tetracarbocyclic product. 相似文献
118.
Dr. Lidiya A. Maslovskaya Dr. Andrei I. Savchenko Carly J. Pierce Dr. Glen M. Boyle Dr. Victoria A. Gordon Dr. Paul W. Reddell Prof. Peter G. Parsons Prof. Craig M. Williams 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(6):1525-1534
Investigation of the Australian rainforest plant Croton insularis revealed seven new cis-, two new trans-cyclopropane casbanes, and the first trans-cyclopropane seco-casbane. The relative configuration of the cyclopropane moiety for all compounds (EBC-182, 217, 218, 220, 343, 357, 358, 361, 365, 373; EBC=EcoBiotics Compound) was assigned using 13C NMR data. Comparison of the experimental electronic circular dichroism (ECD) spectra with the theoretical curves, calculated by TD-DFT at the B3LYP/6-31+G**//B3LYP/6-31+G** level, in conjunction with NOE data afforded the absolute configuration. EBC-180, 181 and 220 displayed potent activity against cervical carcinoma (HeLa cells). 相似文献
119.
Adare A Afanasiev S Aidala C Ajitanand NN Akiba Y Al-Bataineh H Alexander J Aoki K Aramaki Y Atomssa ET Averbeck R Awes TC Azmoun B Babintsev V Bai M Baksay G Baksay L Barish KN Bassalleck B Basye AT Bathe S Baublis V Baumann C Bazilevsky A Belikov S Belmont R Bennett R Berdnikov A Berdnikov Y Bickley AA Bok JS Boyle K Brooks ML Buesching H Bumazhnov V Bunce G Butsyk S Camacho CM Campbell S Chen CH Chi CY Chiu M Choi IJ Choudhury RK Christiansen P Chujo T Chung P Chvala O Cianciolo V Citron Z 《Physical review letters》2011,107(25):252301
Flow coefficients ν(n) for n=2, 3, 4, characterizing the anisotropic collective flow in Au+Au collisions at √s(NN)=200 GeV, are measured relative to event planes Ψ(n), determined at large rapidity. We report ν(n) as a function of transverse momentum and collision centrality, and study the correlations among the event planes of different order n. The ν(n) are well described by hydrodynamic models which employ a Glauber Monte Carlo initial state geometry with fluctuations, providing additional constraining power on the interplay between initial conditions and the effects of viscosity as the system evolves. This new constraint can serve to improve the precision of the extracted shear viscosity to entropy density ratio η/s. 相似文献
120.
Adare A Afanasiev S Aidala C Ajitanand NN Akiba Y Al-Bataineh H Alexander J Angerami A Aoki K Apadula N Aramaki Y Atomssa ET Averbeck R Awes TC Azmoun B Babintsev V Bai M Baksay G Baksay L Barish KN Bassalleck B Basye AT Bathe S Baublis V Baumann C Bazilevsky A Belikov S Belmont R Bennett R Berdnikov A Berdnikov Y Bhom JH Blau DS Bok JS Boyle K Brooks ML Buesching H Bumazhnov V Bunce G Butsyk S Campbell S Caringi A Chen CH Chi CY Chiu M Choi IJ Choi JB Choudhury RK Christiansen P Chujo T 《Physical review letters》2011,107(17):172301
Back-to-back hadron pair yields in d+Au and p+p collisions at √s(NN)=200 GeV were measured with the PHENIX detector at the Relativistic Heavy Ion Collider. Rapidity separated hadron pairs were detected with the trigger hadron at pseudorapidity |η|<0.35 and the associated hadron at forward rapidity (deuteron direction, 3.0<η<3.8). Pairs were also detected with both hadrons measured at forward rapidity; in this case, the yield of back-to-back hadron pairs in d+Au collisions with small impact parameters is observed to be suppressed by a factor of 10 relative to p+p collisions. The kinematics of these pairs is expected to probe partons in the Au nucleus with a low fraction x of the nucleon momenta, where the gluon densities rise sharply. The observed suppression as a function of nuclear thickness, p(T), and η points to cold nuclear matter effects arising at high parton densities. 相似文献