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31.
Isospin Effect on the Emission Mechanism of Hot Nuclei in 35MeV/u 40Ar +112Sn/124Sn Reactions
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Wu Heyu Xiao Zhigang Li Zuyu Wang Hpmgweo Duan Limin Zhang Baoguo Liu Yongying Wang Sufang Jin Genming Xiao Guoqing Guo Zhongyan Zhu Yongtai 《中国物理C(英文版)》1999,23(11):1115-1118
As an extension of radioactive ion beam physics, the research on isospin dependent properties of hot nuclei has increasingly attracted considerable interest. The isospin effect on the decay of hot nuclei in reactions 35MeV/u 40Ar+112Sn/124Sn has been investigared. It is concluded that due to Coulomb repulsion and instability, proton-rich hot nuclei probably emit prides such as a with high energy to increase their neutron-proton ratio. Moreover, the decay chain for those particles is seemingly long and the emission Probability is high. Thus, the conventional observations, for instance, the ‘slope temperature’ extracted from energy spectrum, may very appreciably with the measured particles. 相似文献
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采用非同时读出条件下的两波耦合实验装置,以单束光入射Ce∶KNSBN光折变晶体,系统研究了Ce∶KNSBN晶体中光扇效应随入射光偏振态、入射光强度、光入射角的变化情况。结果表明异常偏振光入射晶体时光扇效应明显,且存在明显的入射光强度阈值特性,入射光强度阈值为38.2mW/cm2;相同光入射角下,稳态光扇强度随入射光强度的增强而明显变大;对应相同的入射光强度,稳态光扇强度随光入射角θ的增大而增大,当θ为15°时到达峰值,而后随θ的增大而逐渐减小。同时对光扇效应的入射光强度阈值特性以及稳态光扇强度随入射光偏振态、入射光强度、光入射角的变化作出了相应的物理解释。 相似文献
34.
Ruifei Su Hongyu Wei Xin Zhang Sufang Ma Jing Yan Yuan Cui Zhao Zhang 《Journal of heterocyclic chemistry》2014,51(3):669-673
A series of novel monodisperse, well‐defined molecules with a pyridine core and carbazole arms were synthesized by simple procedures with Iodo‐reaction and Ullmann reaction. Their structures were confirmed by IR, 1H NMR, 13C NMR, and elementary analysis. Moreover, the fluorescence spectra showed that these compounds exhibited strong fluorescence with the maximum wavelengths ranging from 373 to 385 nm. 相似文献
35.
Sufang Wang Weifang Yang Mingxia Shi Xiaoli Sun Wenyue Pang Guoqing Wang 《Chromatographia》2013,76(9-10):529-534
PVC films with different thickness and different contents of 9 phthalate plasticizers (PAEs) were manufactured according to a uniform design method. The migration contents of PAEs in isooctane, which was set as a fatty foods simulant, were first determined using GC-MS analysis. It was found that the chromatographic peaks of diisononyl ortho-phthalate (DINP) and diisodecyl ortho-phthalate (DIDP) very considerably overlapped, with a lower signal to noise ratio (SNR). For resolution of the noisy overlapped peaks, twice continuous wavelet transform (CWT) was adopted. Then, the migration models of PAEs were obtained by the non-negative least squares method (NNLS). The results show that the noisy overlapped peaks were successfully resolved with increasing the SNR 10 times; the migration ratio of the 9 PAEs at 70 °C are located with the range 0.0556–0.3383 %; the migration amount of a specific plasticizer is proportional to its content and some coexisting plasticizers; temperature is a significant impact factor for the migration process. The proposed chemometric-assisted GC-MS analysis provides a new approach for investigation of this complex process. 相似文献
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Glycolysis product of the waste PET was used to synthesis of 2-hydroxyethyl-4-{[(2-(prop-2-enoyloxy)ethoxy]carbonyl}benzoate (HETA) and further application in the emulsion polymerization of styrene/(meth)acrylic monomers. The resulting polymer dispersion was characterized by FTIR, DLS, TEM, and TGA. The experimental results reveal that HETA plays an important role in thermal, mechanical and other properties of the resulting polymer film. 相似文献
38.
Jinping Song Qi Ma Sufang Zhang Yong Guo Chuan Dong 《Journal of Cluster Science》2016,27(4):1203-1212
A rapid one-step preparation approach of silver nanoparticles (AgNPs) was reported by employing formamidinesulfinic acid as reducing agent and soluble starch as stabilizing agent. The formation of AgNPs was further confirmed by using UV–Vis absorption spectroscopy, X-ray diffraction spectroscopy and transmission electron microscopy techniques. The resultant AgNPs could be directly used for the colorimetric reaction with metal ions. The results showed that Al3+, Cr3+, Fe3+ and Hg2+ ions could induce the color change of AgNPs from yellow to pink (Al3+), orange (Cr3+) and colorless (Fe3+ and Hg2+), respectively, which can be observed by the naked eye. Based on these, a sensitive colorimetric sensor for Al3+, Fe3+, Cr3+ and Hg2+ ions detection was developed. 相似文献
39.
Xinping Lin Sasa Liu Ruiqi Bao Ning Gao Sufang Zhang Rongqian Zhu Zongbao Kent Zhao 《Applied biochemistry and biotechnology》2017,181(3):867-883
The biogenic iron oxide/hydroxide materials possess useful combination of physicochemical properties and are considered for application in various areas. Their production does not require special investments because these compounds are formed during cultivation of neurophilic iron bacteria. Bacteria from genus Leptothrix develop intensively in the Sphaerotilus-Leptothrix group of bacteria isolation medium and feeding media of Fedorov and Lieske. These media are different in their composition which determined the present study as an attempt to clear up the reasons that define the differences in the composition of the laboratory-obtained biomasses and the natural biomass finds. FTIRS, Mössbauer spectroscopy, and XRD were used in the research. Comparative analysis showed that the biomass and control samples contain iron compounds (α-FeOOH, γ-FeOOH, β-FeOOH, γ-Fe2O3) in different ratios. The biomass samples were enriched in oxyhydroxides of higher dispersion. Organic residuals of bacterial origin, SO4, CO3, and PO4 groups were registered in the biogenic materials. 相似文献
40.
[O2Pb3]2(BO3)Br: An Oxidoborate Oxide Bromide with the ∞1[O2Pb3] Double Chains Based on Edge‐sharing OPb4 Tetrahedra
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Lingyun Dong Jiao Yang Shigang Shen Zhenzhen Liu Xiaojing Chen Sufang Sun 《无机化学与普通化学杂志》2017,643(7):471-476
Through extensive research on the PbO / PbBr2 / B2O3 system, a new single crystal of yellow lead‐containing oxyborate bromine, [O2Pb3]2(BO3)Br, was grown from the melt. It crystallizes in the centrosymmetric space group Cmcm (no. 63) of the orthorhombic system with the following unit cell dimensions: a = 9.5748(8) Å, b = 20.841(2) Å, c = 5.7696(5) Å, and Z = 4. The whole structure is characterized by an infinite one‐dimensional (1D) ∞1[O2Pb3] double chain, which is based on the OPb4 oxocentered tetrahedra and considered as the derivative of the continuous sheet of OPb4 tetrahedra from the tetragonal modification of α‐PbO. The 1D ∞1[O2Pb3] double chains are further bridged by the BO3 units through common oxygen atoms to form two‐dimensional (2D) ∞1[[(O2Pb3)(BO3)] layers, with Br atoms situated between the layers. IR spectroscopy, UV/Vis/NIR diffuse reflectance spectroscopy, and thermal analysis were also performed on the reported material. 相似文献