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91.
利用密度泛函理论通过计算吸附能量、HOMO/LUMO能隙变化、电荷转移、结构扭曲等研究二氧化氮分子在B12N12纳米笼的吸附.此外,通过计算B12N12的电子结合能、Gibbs自由能、态密度和分子表面的静电势研究其稳定性和其它特性.B12N12纳米笼吸附二氧化氮显示三种构型.B12N12团簇的HOMO/LUMO能隙变化对二氧化氮分子的存在非常敏感,从自由团簇的6.84 eV降为NO2/团簇稳定团簇的3.23 eV.团簇的导电性被极大地提高,表明B12N12纳米簇可能是潜在的二氧化氮气体分子检测传感器. 相似文献
92.
Faramarz Rostami Charati Zinatossadat Hossaini Mohammad R. Hosseini‐Tabatabaei 《Journal of heterocyclic chemistry》2012,49(1):154-160
A straightforward and efficient method for the synthesis of 1,2‐dihydroisoquinolines via a one‐pot, three‐component reaction of isoquinoline, activated acetylenes, and NH‐acids in water at 70°C without using any catalyst is reported. The method offers several advantages including high yields of products and an easy workup procedure. J. Heterocyclic Chem., (2012). 相似文献
93.
Mohamad Javad Tahmasebi Birgani Fatemeh Seif Nahid Chegeni Mohamad Reza Bayatiani 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(3):1367-1370
In consideration the radiological properties of materials and studying the scattering processes in atomic and nuclear physics,
the effective atomic and mass numbers is widely employed. These numbers have been calculated for any mixed or composite materials
in interaction with high energy photons (Linac in radiation therapy). A pair equation in terms of these numbers is obtained.
The first equation has been derived from the conservation of mass energy law and the second by minimizing the binding energy
from the semiempirical mass formula (Myers and Swiatecki formula) that gives a relation between atomic and mass numbers for
stable nuclei approximately. By these equations one can obtain the effective atomic and mass numbers for any compound or mixed
materials uniquely. These numbers are calculated for some materials and compared with the other studies. 相似文献
94.
95.
Babak Momeni Ehsan Shah Hosseini Murtaza Askari Mohammad Soltani Ali Adibi 《Optics Communications》2009,282(15):3168-697
A combination of negative refraction and diffraction compensation in a superprism-based photonic crystal structure is used to demonstrate a compact on-chip photonic crystal spectrometer. This structure provides strong dispersion and signal isolation, which are essential for forming an efficient and compact spectrometer. Performance of these spectrometers as spectral pattern detectors is discussed. The experimental results show that a PC structure with 80 μm × 220 μm dimension can locate a single spectral feature with better than 10 pm accuracy over a bandwidth of 50 nm around 1550 nm center wavelength at an output signal-to-noise ratio of 13 dB. 相似文献
96.
97.
Ali A. Moshfegh Effat Beladi Lida Radnia Afsaneh S. Hosseini Soosan Tofigh Gholam H. Hakimelahi 《Helvetica chimica acta》1982,65(4):1264-1270
The synthesis of the title compounds ( 1 and 3 ) is described. Some of the compounds prepared were found to be active against a number of pathogenic microorganisms in vitro. Structure-activity relationship is briefly discussed. 相似文献
98.
We have studied the stability, the electronic, and the magnetic properties of Co2MnSi(001) thin films for 15 different terminations using density functional theory calculations. The phase diagram obtained by ab initio atomistic thermodynamics shows that in practice the MnSi, pure Mn, or pure Si terminated surfaces can be stabilized under suitable conditions. Analyzing the surface band structure, we find that the pure Mn termination, due to its strong surface-subsurface coupling, preserves the half-metallicity of the system, while surface states appear for the other terminations. 相似文献
99.
Javad?AzizianEmail author Ali R.?Karimi Hamedeh?Arefrad Ali A.?Mohammadi Mohammad R.?Mohammadizadeh 《Monatshefte für Chemie / Chemical Monthly》2004,135(6):729-733
Summary. We report on the addition of dialkyl acetylenedicarboxylate to 1-alkylisatins or tryptanthrine in the presence of triphenylphosphine which leads to highly functionalised novel unsaturated -spirolactones. 相似文献
100.
Javad Namazi 《Journal of Mathematical Analysis and Applications》2004,290(2):553-562
Let 1<p<∞, and k,m be positive integers such that 0(k−2m)pn. Suppose ΩRn is an open set, and Δ is the Laplacian operator. We will show that there is a sequence of positive constants cj such that for every f in the Sobolev space Wk,p(Ω), for all xΩ except on a set whose Bessel capacity Bk−2m,p is zero. 相似文献