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排序方式: 共有230条查询结果,搜索用时 15 毫秒
1.
Avdic Senada Demirovic Damir Hadzimustafic Edin Cickusic Zerina Sehic Faruk 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2645-2654
Journal of Radioanalytical and Nuclear Chemistry - Responses of the hand-held gamma monitors available for the ambient dose equivalent rate measurements in the Federation of Bosnia and Herzegovina... 相似文献
2.
E. V. McCloskey A. Dey R. M. Parr N. Aras A. Balogh J. Bostock A. Borell S. Krishnan G. Lobo L. L. Qin Y. Zhang S. Cvijetic V. Zaichick M. Lim-Abraham K. Bose S. Wynchank G. V. Iyengar 《Journal of Radioanalytical and Nuclear Chemistry》2004,259(2):341-345
In 1994, the International Atomic Energy Agency (IAEA) initiated a 5-year Co-ordinated Research Project (CRP) to determine
geographical and racial differences in peak bone mineral density (BMD) in men and women aged 15-49 years. The study demonstrates
that there are distinct global differences in BMD at the hip and spine in both men and women approximating to one population
standard deviation between populations with the highest and lowest BMD. These differences persist following adjustments for
age, sex and body size. Such information is valuable in understanding the reasons for global differences in fracture rate
and predicting future trends in fracture incidence.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
F. Forkusuz S. Işıklı S. Akın M. Ungan A. Şenköylü N. K. Aras 《Journal of Radioanalytical and Nuclear Chemistry》2004,259(3):365-368
The standard method to diagnose and follow-up osteoporosis is the measurement of bone mineral density (BMD) using dual X-ray
absorptiometry (DEXA). Manufacturers' manuals of DEXA devices state the intrascanner coefficient of variance is less than
0.01 g/cm2. The aim of this study was to evaluate the in vivo coefficient of variance of a Lunar DPX scanner in male and female healthy
adult subjects. Average BMD for females and males were 1.170±0.091 g/cm2 and 1.272±0.115 g/cm2, respectively. Monthly phantom measurements provided and controlled by the manufacturer were 1.243±0.008 g/cm2 (range 1.222 to 1.257) and the coefficient of variance was 0.006. It is concluded that the in vivo coefficient of variance
of DEXA devices can slightly be higher than that proposed by the manufacturer.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
Gurkan Hizal Umit Tunca Sermin Aras Humeyra Mert 《Journal of polymer science. Part A, Polymer chemistry》2006,44(1):77-87
Copper‐catalyzed controlled/living radical polymerization (LRP) of styrene (St) was conducted using the silica gel‐supported CuCl2/N,N,N′,N′,N″‐pentamethyldiethylenetriamine (SG‐CuCl2/PMDETA) complex as catalyst at 110 °C in the presence of a definite amount of air. This novel approach is based on in situ generation and regeneration of Cu(I) via electron transfer reaction between phenols and Cu(II). Sodium phenoxide or p‐methoxyphenol was used as a reducing agent of Cu(II) complexes in LRP. The number–average molecular weight, Mn,GPC, increases linearly with monomer conversion and agrees well with the theoretical values up to 85% conversion The molecular weight distribution, Mw/Mn, decreases as the conversion increases and reaches values below 1.2. The catalyst was recovered in aerobic condition and reused in copper‐catalyzed LRP of St. For the second run, the number–average molecular weights increased with monomer conversion and the polydispersities decreased as the polymerization proceeded and reached to the value <1.3 at 81% conversion. The recycled catalyst retained 90% of its original activity in the subsequent polymerization. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 77–87, 2006 相似文献
5.
Z. Buyukmumcu H. N. Erten N. K. Aras 《Journal of Radioanalytical and Nuclear Chemistry》1994,181(1):175-188
Extensive experimental and evaluated yield data are now available for the fragments in low energy nuclear fission. Using these data we re-examined the influence of even nuclear numbers and closed shells on the mass and charge distribution in low energy fission. We used WAHL's Zp model and Ap model. We also examined the effects ofZ=50,N=82 and possiblyN=88 shells. A new method was developed based on two Gaussian curves for the even and odd products. TheEOZ andEON values calculated are based on these different methods and are seen to be consistent with each other in spite of the somewhat different definitions of the even-odd effect. The even-odd effect decreases with an increasing fissility parameter. TheEON values are substantially lower than the correspondingEOZ values, probably due to the effect of washing out the neutron pairing effect by prompt neutron emission. The magnitude of the even-odd effect varies with different mass regions. TheEOZ andEON values decrease as they go from asymmetric to symmetric regions in mass distributions. 相似文献
6.
A bifunctional amido-thiophene namely hexamethylene (bis-3-thiophene acetamide) (HMTA) was synthesized by the reaction of 3-thiophene acetic acid with hexamethylene diamine. Copolymerization in the presence of thiophene was achieved electrochemically in tetrabutylammonium tetrafluoroborate/acetonitrile (TBAFB/AN). Spectroelectrochemical analysis of the resulting copolymer [P(HMTA-co-Th)] reflected electronic transitions at 505 nm, 740 nm and ∼1000 nm, revealing π to π* transition, polaron and bipolaron band formation respectively. Switching ability was evaluated by a kinetic study via measuring the transmittance (%T) at the maximum contrast. Dual type polymer electrochromic devices (ECDs) based on P(HMTA-co-Th) and poly(ethylene dioxythiophene) (PEDOT) have been constructed. Spectroelectrochemistry, switching ability and stability of the devices were investigated by UV-vis spectroscopy and cyclic voltammetry. These devices exhibit low switching voltages (between 0.0 V and +1.6 V), short switching times with reasonable switching stability under atmospheric conditions. 相似文献
7.
(1R,2R)-1,2-bis-(5-amino-1,3,4-thiadiazole-2-yl)ethane-1,2-diol (L) has been prepared by the reaction of thiosemicarbazide with (2R,3R)-(+)-tartaric
acid (I) and phosphorous oxychloride, and its complexes with Co(II), Ni(II) and Cu(II) have been obtained. The structures
of the ligand and its complexes have been established by i. r., 1H- and 13C-n.m.r. spectra, u.v.–vis–nir spectroscopy, elemental analyses, T.g.-D.t.a. and magnetic susceptibility measurements. 相似文献
8.
Regio- and stereoselectivities in cycloadditions of nitrones to dipolarophiles bearing an allylic oxygen, which furnishes substituted-isoxazolidine analogs of the furanose ring of nucleosides, have been investigated. Although the obtained regioselectivities are anticipated, a rationalization of the preferred formation of endo-cycloadducts necessitates the involvement of an allylic oxygen in secondary interaction. The obtained isoxazolidines display cytotoxic activities against a number of human cancer cell lines. 相似文献
9.
In this study, Fe3O4@TiO2 nanoparticles were synthesized as a new Positron Emission Tomography/Magnetic Resonance Imaging (PET/MRI) hybrid imaging agent and radiolabeled with 89Zr. In addition, Fe3O4 nanoparticles were synthesized and radiolabeled with 89Zr. Df-Bz-NCS was used as bifunctional ligand. The nanoconjugates were characterized with transmission electron microscopy, scanning electron microscopy, and dynamic light scattering. Radiolabeling yields were 100%. Breast and prostate cancer cell affinities and cytotoxicity were determined using in vitro cell culture assays. The results demonstrated that Fe3O4@TiO2 nanoparticles are promising for PET/MR imaging. Finally, unlike Fe3O4 nanoparticles, Fe3O4@TiO2 nanoparticles showed a fluorescence spectrum at an excitation wavelength of 250 nm and an emission wavelength of 314 nm. Therefore, in addition to bearing the magnetic properties of Fe3O4 nanoparticles, Fe3O4@TiO2 nanoparticles display fluorescence emission. This provides them with photodynamic therapy potential. Therefore multimodal treatment was performed with the combination of PDT and RT by using human prostate cancer cell line (PC3). The development of 89Zr-Df-Bz-NCS-Fe3O4@TiO2 nanoparticles as a new multifunctional PET/MRI agent with photodynamic therapy and hyperthermia therapeutic ability would be very useful. 相似文献
10.
Sevtap Yildiz Faruk Yilmaz Haluk Özbek Önder Pekcan Koi˙chi˙ Ito 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1573-1588
Random copolymers of poly(ethylene oxide) macromonomer with p‐vinylbenzyl end‐functional group (PEOVB) and liquid crystalline monomer, namely 6‐(4‐cyanobiphenyl‐4′‐oxy)hexyl acrylate (COA), were prepared by conventional free radical polymerization. A living anionic polymerization technique was employed for the synthesis of PEO macromonomers bearing p‐vinylbenzyl moiety at one end. The photon transmission method was also applied to study the phase transitions of COA monomer and its random copolymer with PEO. It was found that, for both samples, the nematic‐smectic A transition is continuous, but the critical fluctuation regions do not allow to obtain 3D XY values. Instead, we have obtained the values close to mean field regime. Scaling of thermal hystersis for random copolymer sample near the nematic‐isotropic transition was studied as well. Thermal hysteresis loops were produced under linearly varying temperature. It was shown that the areas of the hysteresis loops scale with the temperature scanning rate with an exponent being equal to 0.614 which is in good agreement with the field‐theoretical value. 相似文献