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121.
MI Zhiming CHEN Yao CHEN Xiaodong YAN Liuqing GU Qiang ZHANG Hanqi CHEN Chunhai ZHANG Yumin 《高等学校化学研究》2018,34(3):369-374
A small molecule fluorescent probe, 4-[2-(4-chlorophenyl)-4,5-diphenyl-1H-imidazol-1-yl]aniline(L) for detecting Ag+ ion was gently synthesized via one-pot multi-component reaction catalyzed by H3[PW12O40] under solvent-free microwave irradiation. When the concentration of Ag+ ion changed from 0 to 8.0×10−6 mol/L in the solution of H2O/CH3OH(19:1, volume ratio), the fluorescence emission spectrum was blue-shifted and accompanied by a gradual increase in fluorescence intensity with a low detection limit of 3.0×10−11 mol/L. Moreover, UV-Vis absorption titration experiment demonstrated a 1:1 stoichiometric ratio and an association constant of (9.95±0.44)×105 L/mol between probe L and Ag+ ion, and thus their complexation mechanism was also proposed and verified. More importantly, this fluorescent probe was remarkably specific for Ag+ ion under the interference of other metal ions and exhibited a wide pH application range of 4.0-8.0. Additionally, preliminary application of this probe was also carried out and satisfactory results were shown. 相似文献
122.
MI Ai-Jun ZUO Wei LI Zeng-Hua Umberto Lombardo 《理论物理通讯》2009,51(6):1113-1116
The 3 P F2 superfluidity of neutron and proton is investigated in isospin-asymmetric nuclear matter within the Brueckner-Hartree-Fock approach and the BCS theory by adopting the Argonne V14 and the Argonne V18 nucleonnucleon interactions. We find that pairing gaps in the 3PF2 channel predicted by adopting the AV14 interaction are much larger than those by the AV18 interaction. As the isospin-asymmetry increases, the neutron 3 pF2 superfluidity is found to increase rapidly, whereas the proton one turns out to decrease and may even vanish at high enough asymmetries. As a consequence, the neutron 3pF2 superfluidity is much stronger than the proton one at high asymmetries and it predominates over the proton one in dense neutron-rich matter. 相似文献
123.
First-principles local density functional calculations are presented for the compounds ZnGa2X4 (X=S,Se). We investigate the bulk moduli and electronic band structures in a defect chalcopyrite structure. The lattice constants and internal parameters are optimized. The electronic structures are analysed with the help of total and partial density of states. The relation between the cohesive energy and the unit cell volume is obtained by fully relaxed structures. We derive the bulk modulus of ZnGa2X4 by fitting the Birch-Murnaghan's equation of state. The extended Cohen's empirical formula agrees well with our ab initio results. 相似文献
124.
Nano-fibrillar arrays are fabricated using polystyrene materials. The average diameter of each fiber is about 300 nm. Experiments show that such a fibrillar surface possesses a relatively hydrophobie feature with a water contact angle of 142°. Nanoscale friction properties are mainly focused on. It is found that the friction force of polystyrene nano-fibrillar surfaces is obviously enhanced in contrast to polystyrene smooth surfaces. The apparent coefficient of friction increases with the applied load, but is independent of the scanning speed. An interesting observation is that the friction force increases almost linearly with the real contact area, which abides by the fundamental Bowden-Tabor law of nano-seale friction. 相似文献
125.
First-principles local density functional calculations are presented for the compounds ZnGa2X4 (X = S, Se). We investigate the bulk moduli and electronic band structures in a defect chalcopyrite structure. The lattice constants and internal parameters are optimized. The electronic structures are analysed with the help of total and partial density of states. The relation between the cohesive energy and the unit cell volume is obtained by fully relaxed structures. We derive the bulk modulus of ZnGa2Xa by fitting the Birch-Murnaghan's equation of state. The extended Cohen's empirical formula agrees well with our ab initio results. 相似文献
126.
Pedro Sancho 《Foundations of Physics》2009,39(4):361-372
We study the correlations (and alignment as a particular case) existent between the fragments originated in a decaying process
when the daughter particles interact. The interaction between the particles is modeled using the potential of coupled oscillators,
which can be treated analytically. This approach can be considered as a first step towards the characterization of realistic
interacting decaying systems, an archetypal process in physics. The results presented here also suggest the possibility of
manipulating correlations using external fields, a technique that could be useful to provide sources of entangled massive
particles. 相似文献
127.
高效液相色谱-质谱联用技术测定人血浆中双氢青蒿素的含量 总被引:10,自引:1,他引:9
建立了测定人血浆中的双氢青蒿素的液相色谱 -质谱联用法。色谱条件 :AlltimaC18 柱 (2.1×150mm ,5μm ,流动相 :甲醇 -水 (体积比85∶15) ;流速 :0.2mL/min ;柱温 :25℃ ;进样量 :20μL。质谱条件 :电喷雾离子源 (ESI) ;用于定量分析的离子分别为m/z307(双氢青蒿素) ,m/z275(蒿甲醚 )。样品用液 -液萃取方法处理。双氢青蒿素的线性范围为5~200μg·L -1,定量下限为5μg·L -1,日内、日间精密度 (RSD)均小于10 % ,萃取回收率在71.5 %~83.2 %之间 (n=5) ,分析方法回收率在98.4 %~101.9 %之间 (n=5)。本法操作简便、准确、灵敏度高 ,适用于双氢青蒿素的药代动力学研究 相似文献
128.
分别在对二氧环己酮均聚物和对二氧环己酮-乙交酯共聚物中加入增塑剂进行纺丝,制得聚对二氧环己酮单丝缝合线(PDS)和对二氧环己酮-乙交酯共聚物单丝缝合线(PDG).用DSC方法研究了增塑剂含量对PDS缝合线热性能的影响和不同热定型条件的PDG缝合线的热性能,测试了热定型温度对PDG缝合线初始强度、模量及柔量的影响,考察了增塑剂含量对两种缝合线的生物降解性能和力学降解性能影响.研究结果表明,PDS缝合线的玻璃化转变温度Tg、结晶温度Tc以及熔融温度Tm均随着增塑剂含量的增加而降低,但其结晶能力增加.随着热定型温度的增加,PDG缝合线的初始打结强度、熔融热均提高,熔融温度Tm基本保持不变.两种缝合线的强度保留率随着增塑剂含量的增加均先增加后减小,而重量保留率随着增塑剂含量增加始终减小. 相似文献
129.
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