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151.
152.
Fonseca SM Barker AL Ahmed S Kemp TJ Unwin PR 《Chemical communications (Cambridge, England)》2003,(8):1002-1003
Using scanning electrochemical microscopy (SECM) we have measured quantitatively the depletion of O2 during the photodegradation of 4-chlorophenol at supported TiO2 films for the first time and established the connection between Cl-formation and O2 depletion rates. 相似文献
153.
154.
Anderson PA Armstrong AR Barker PD Edmondson MJ Edwards PP Porch A 《Dalton transactions (Cambridge, England : 2003)》2004,(19):3122-3128
Large crystallites of high purity zeolite rho were synthesized by controlled monitoring of the aging and heating period of the mother gel. The microwave conductivity of Rb-rho doped with up to 20 Rb atoms per unit cell was measured over the temperature range 15-300 K, and the structures of three of the samples were examined through Rietveld analysis of powder neutron diffraction data. At low concentrations of rubidium dopant the observed microwave responses were dominated by polarization effects. In the sample Rb(17)/Rb-rho a strongly temperature-dependent electronic contribution to the conductivity was observed above approximately =150 K. In Rb(20)/Rb-rho, conductivities in the range 1.5-2.3 Sm(-1) were observed between 15 and 300 K. This residual conductivity at 15 K, unprecedented in a zeolite, indicates that the sample is indeed metallic; however, the values of conductivity measured are low in comparison to conventional metals and comparable to those of doped semiconductors. The evolution of the conducting behaviour is discussed in relation both to observed structural and to possible electronic changes occurring within the samples on metal doping. 相似文献
155.
Laurence Barker 《代数通讯》2013,41(7):3377-3399
Various representation-theoretic parameters of a finite group are shown to satisfy formulas similar to formulas appearing in reformulations by Kölshammer, Robinson, and Thévenaz of Alperin's Conjecture. The conjecture itself is reformulated again, now as a statement not mentioning characters or conjugacy classes. 相似文献
156.
Zexin Jin Ze‐Fan Yao Kayla P. Barker Jian Pei Yan Xia 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(7):2056-2061
Polycyclic conjugated hydrocarbons containing antiaromatic four‐membered cyclobutadienoids (CDB) are of great fundamental and technical interest. However, their challenging synthesis has hampered the exploration and understanding of such systems. Reported herein is a modular and efficient synthesis of novel CBD‐containing acene analogues, dinaphthobenzo[1,2:4,5]dicyclobutadiene (DNBDCs), with orthogonally tunable electronic properties and molecular packing. The design also features strong antiaromaticity of the CBD units, as revealed by nucleus‐independent chemical shift and anisotropy of the induced current density calculations, as well as X‐ray crystallography. Tuning the size of silyl substituents resulted in the most favorable “brick‐layer” packing for triisobutylsilyl‐DNBDC and a charge mobility of up to 0.52 cm2 V?1 s?1 in field‐effect transistors. 相似文献
157.
An improved method for the preparation of 2,3-unsubstituted benzofurans is described. Specifically, the PPA catalysed cyclization of aryloxyacetaldehyde acetals to give (4–7)-substituted benzofurans has been achieved. 相似文献
158.
H. Rubinsztein-Dunlop B. Littleton P. Barker P. Ljungberg Y. Malmsten 《Experiments in fluids》2001,30(1):36-42
A flow tagging technique based upon ionic fluorescence in strontium is investigated for applications to velocity measurements
in gas flows. The method is based upon a combination of two laser based spectroscopic techniques, i.e. resonantly-enhanced
ionisation and laser-induced ionic fluorescence. Strontium is first ionised and then planar laser-induced fluorescence is
utilised to give 2D `bright images' of the ionised region of the flow at a given time delay. The results show that this method
can be used for velocity measurements. The velocities were measured in two types of air–acetylene flames – a slot burner and
a circular burner yielding velocities of 5.1 ± 0.1 m/s and 9.3 ± 0.2 m/s, respectively. The feasibility of the method for
the determination of velocities in faster flows than those investigated here is discussed.
Received: 5 November 1998/Accepted: 19 January 2000 相似文献
159.
A. Cappelli R. Tuffi K. Schwertassek K. Czapla J. Plail E. Freedman H. Nechamkin R. Gerber K. Lathrop H. Rath O. Mecheels J. W. Groß E. v. Roll K. Heidler S. G. Barker B. A. Ryberg W. I. Tepnin P. M. Heertjes H. Anton F. Riecke W. Sserdjukow und N. A. Juschkow 《Fresenius' Journal of Analytical Chemistry》1944,127(1):220-227
Ohne Zusammenfassung 相似文献
160.
Mohammed S. Aldughaim Munitta Muthana Fatimah Alsaffar Michael D. Barker 《Molecules (Basel, Switzerland)》2021,26(1)
Doxorubicin is a cytotoxic anthracycline derivative that has been used as a chemotherapeutic in many different forms of human cancer with some success. However, doxorubicin treatment has several side-effects, the most serious of which is cardiomyopathy, that can be fatal. Doxorubicin encapsulation in PEGylated liposomes (Doxil®) has been shown to increase tumour localisation and decrease cardiotoxicity. Conversely, the stability of such liposomes also leads to increased circulation times and accumulation in the skin, resulting in palmar planter erythrodysesthesia, while also limiting release of the drug at the tumour site. Specific targeting of such liposomes to tumour cells has been attempted using various receptor-specific peptides and antibodies. However, targeting a single epitope limits the likely number of tumour targets and increases the risk of tumour resistance through mutation. In this report, Doxil® was coupled to peptide sequence p700 derived from tissue inhibitor of metalloproteinase 3. This Doxil® -P700 complex results in an approximately 100-fold increase in drug uptake, relative to Doxil® alone, by both mouse and human breast cancer cells and immortalised vascular cells resulting in an increase in cytotoxicity. Using p700 to target liposomes in this way may enable specific delivery of doxorubicin or other drugs to a broad range of cancers. 相似文献