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1.
2.
The production of track-spots in CR-39 detectors for alpha particles and the subsequent optical counting of the detectors are often influenced by foreign substances deposited on the surface of the detectors. The removal of these substances can be achieved using chemicals for pre-irradiation treatment. Two methods of pre-irradiation treatment were studied in the present experiments. One of them involves the dipping of the detectors in ethanol. In the other method, the detectors were treated in 6N KOH etchant prior to exposure. It was found that prolonged treatment could only produce a reduction in the track density of less than 20%. 相似文献
3.
Racemic 6-gingerol can be obtained in a one-pot reaction by hexanal addition to the dianion of zingerone at low temperature. Similarly, addition of octanal or decanal to the dianion provides 8-gingerol or 10-gingerol, respectively. Acid treatment of the gingerols allows for formation of the corresponding shogaols. 相似文献
4.
Synthesis and anticancer properties of RGD peptides conjugated to nitric oxide releasing functional groups and abiraterone 总被引:1,自引:0,他引:1
A series of analogues of the integrin binding aspartic acid-glycine-arginine (RGD) peptide sequence were synthesised conjugated to nitric oxide (NO) donating functional groups. Also the cytotoxicity of abiraterone, a prostate cancer drug, was explored when it was conjugated in three part constructs to RGD sequences and NO releasing heterocycles. In general the analogues showed integrin binding affinity comparable to RGD reference compounds, and all released NO by the Griess test assay. Two analogues exhibited significant cytotoxic effects against PC3 and MCF7 cell lines. 相似文献
5.
6.
P.G. Fleming J.D. Holmes D.J. Otway M.A. Morris 《Journal of solid state chemistry》2011,184(9):2595-2600
Mixed oxide solid solutions are becoming ever more commercially important across a range of applications. However, their synthesis can be problematical. Here, we show that ceria-lanthana solid solutions can be readily prepared via simple precipitation using hexamethylenetetramine. However, the solution chemistry can be complex, which results in the precipitated particles having a complex structure and morphology. Great care must be taken in both the synthesis and characterisation to quantify the complexity of the product. Even very high heat treatments were not able to produce highly homogeneous materials and X-ray diffractions reveals the non-equilibrium form of particles prepared in this way. Unexpected crystal structures are revealed including a new metastable cubic La2O3 phase. 相似文献
7.
Evan S. O'Brien Brian Fuglestad Henry J. Lessen Matthew A. Stetz Danny W. Lin Bryan S. Marques Kushol Gupta Karen G. Fleming A. Joshua Wand 《Angewandte Chemie (International ed. in English)》2020,59(27):11108-11114
The internal motions of integral membrane proteins have largely eluded comprehensive experimental characterization. Here the fast side‐chain dynamics of the α‐helical sensory rhodopsin II and the β‐barrel outer membrane protein W have been investigated in lipid bilayers and detergent micelles by solution NMR relaxation techniques. Despite their differing topologies, both proteins have a similar distribution of methyl‐bearing side‐chain motion that is largely independent of membrane mimetic. The methyl‐bearing side chains of both proteins are, on average, more dynamic in the ps–ns timescale than any soluble protein characterized to date. Accordingly, both proteins retain an extraordinary residual conformational entropy in the folded state, which provides a counterbalance to the absence of the hydrophobic effect. Furthermore, the high conformational entropy could greatly influence the thermodynamics underlying membrane‐protein functions, including ligand binding, allostery, and signaling. 相似文献
8.
The structure of 0.35 monolayers of platinum deposited onto Cu(110) has been investigated using medium energy ion scattering. Quantitative analysis of the data has been performed using the VEGAS routine. It was found that platinum atoms mostly occupy the second layer with a first interlayer distance of d12 = 123 ± 4 pm and a separation of first and third layers of d13= 142? 10+ 4 pm. These represent a contraction of 4% and an expansion of 11% respectively from the ideal termination of the Cu(110) surface. There is clear evidence of the presence of some platinum in the third layer. 相似文献
9.
T. Pinheiro A. Barreiros L. C. Alves M. Neres R. Fleming J. N. Silva P. Filipe R. Silva 《Journal of Radioanalytical and Nuclear Chemistry》2009,281(2):161-164
Skin as a manageable organ can provide direct or indirect information of tissue iron overload resulting from inherited disorders
as hemochromatosis. Patients with hemochromatosis were evaluated at three consecutive phases along the therapy programme.
Nuclear microprobe techniques were used to assess skin iron and Total Reflection X-ray Fluorescence to determine the plasma
iron concentrations. Results showed that iron pools were differently correlated at the three therapy phases. These variations
highlighted the value of skin iron content to assess organ iron deposition and therapy efficacy. Skin iron content can be
used for a better management of patients with iron overload pathologies. 相似文献
10.
Bulman–Fleming Sydney 《代数通讯》2013,41(3):951-964
The tree main results of this paper deal with the generating vectors of simple infinite and finite dimesional modules arising as composition factors of the Kac modules K↓ G 0 and K of the Lie superalgebra sl(m/n). 相似文献