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91.
Nuclear data for neutron activation analysis are reviewed critically. Available sources of neutron cross sections and related quantities, radioactive decay half-lives, gamma-ray energies and absolute intensities, as well as prompt gamma-ray data are assessed from the viewpoint of quantitative analysis. New developments in the production and dissemination of such data are also described, and practical recommendations are formulated. Special emphasis is given to the traceability of sources, the accuracy and age of data, and to electronic access via Internet.  相似文献   
92.
There is increasing interest in the use of natural compounds with beneficial pharmacological effects for managing diseases. Curcumin (CUR) is a phytochemical that is reportedly effective against some cancers through its ability to regulate signaling pathways and protein expression in cancer development and progression. Unfortunately, its use is limited due to its hydrophobicity, low bioavailability, chemical instability, photodegradation, and fast metabolism. Nanoparticles (NPs) are drug delivery systems that can increase the bioavailability of hydrophobic drugs and improve drug targeting to cancer cells via different mechanisms and formulation techniques. In this review, we have discussed various CUR-NPs that have been evaluated for their potential use in treating cancers. Formulations reviewed include lipid, gold, zinc oxide, magnetic, polymeric, and silica NPs, as well as micelles, dendrimers, nanogels, cyclodextrin complexes, and liposomes, with an emphasis on their formulation and characteristics. CUR incorporation into the NPs enhanced its pharmaceutical and therapeutic significance with respect to solubility, absorption, bioavailability, stability, plasma half-life, targeted delivery, and anticancer effect. Our review shows that several CUR-NPs have promising anticancer activity; however, clinical reports on them are limited. We believe that clinical trials must be conducted on CUR-NPs to ensure their effective translation into clinical applications.  相似文献   
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A value of 84 ± 44 ps has been established for the half-life of the first 3? state of96Zr, using the centroid shift method. It is shown that the corresponding large electric octupole transition strength is in accordance with systematics, suggesting largest octupole collectivity when both the 1g9/2 Proton and 1h11/2 neutron orbitals are nearly empty due to the Z=40, N=56 double subshell closure.  相似文献   
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We describe the general form of bijective maps on the space of all Hilbert space effects or all observables on a finite dimensional space which preserve the spectral order in both directions. The first author was supported by the Hungarian National Foundation for Scientific Research (OTKA), Grant No. T043080, T046203, and the second author was partially supported by a grant from the Ministry of Science of Slovenia. Both authors were supported by a joint Hungarian-Slovene grant, Reg. No. SLO-5/05.  相似文献   
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5-Amino-1,2,4-triazoles reacted with alifatic β-oxo-esters to yield besides the unexpected 1,2,4-triazolo-[1,5-a]-1,3,5-benzotriazepin-5-one derivative 7 either the corresponding esters 5 and 6 or a 1:2 condensation product 8. To the contrary alicyclic and heterocyclic β-oxo-esters formed in the above reaction only derivatives 7. The proposed mechanism of the formation of 7 involving a novel N-carbonylation reaction was proved by the isolation of the by-products and the intermediate of the reaction. Repeating the above reaction with a γ-oxo-ester, namely the ethyl levulinate, derivatives 17 and 18 , respectively, representing two new ring systems were obtained.  相似文献   
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