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Two fluorescent "off-on" probes YYH1 and YYH2 were used for bioimaging mitochondrial polarity and viscosity.  相似文献   
45.
Quantum dots (QDs) were prepared in an organic system through a simple and low-cost wet chemistry method. Polymer beads with a diameter of 60–70 nm and specific functional groups were synthesized by a particular seeded emulsion polymerization technique. QDs were embedded in the polymer beads with the specific functional groups through dissolving and swelling method, which provided the condition for the conjunction of biomolecules and QDs as fluorescent probes. The prepared composites were characterized with UV-Vis, PL, TEM, FTIR, CLSM and conductance titration etc. The results show that QDs are successfully embedded in polymer beads, which breaks the limitation that the conjunction of biomolecules and QDs can be achieved only for those synthesized in aqueous system. __________ Translated from Journal of Shanghai Jiaotong University, 2005, 39(1) (in Chinese)  相似文献   
46.
Zi Gao  Jun Cui  Shu-Bin Pu 《中国化学》1992,10(4):320-324
Highly dispersed α-Fe_2O_3/NaY,NiO/NaY,and CuO/NaY catalyst systems were pre-pared by impregnation method.Dispersion thresholds of the transition metal oxides on NaY" zeolitewere determined by XRD phase analysis.The dispersion capacities of the transition metal oxides on NaYzeolite are much lower than that estimated on the basis of a closed packed monolayer in the micropores.The catalytic activity and selectivity of the highly dispersed oxide catalyst systems for ethylben-zene and cyclohexane dehydrogenation reactions were reported.  相似文献   
47.
研究应用双波长K系数—标准加入吸光光度法同时测定锰和锌二组分混合物.试验确定了锰和锌测定中K_(Mn)与K_(Zn)的回归方程.对合成试样、人发试样测定,结果满意.  相似文献   
48.
活性碳用苯胺处理后,可以减少对C_(60)和C_(70)的不可逆吸附,从而增加C_(60)和C_(70)的分离收率,同时提高了C_(70)的纯度。  相似文献   
49.

By using an asymmetric ligand with triazole and imidazole groups, three Keggin-based complexes were obtained, [Cu(HMET)4(H2O)2](PMo12O40)2·2H2O (1), [Cu3(HMET)4Cl2(H2O)2(XM12O40)2]·4H2O (X?=?Si, M?=?W 2, X?=?Ge, M?=?Mo 3) (MET?=?4-(2-imidazol-1-yl-ethyl)-4H-[1,3,4]triazole). Complex 1 contains discrete Keggin anions and mono-nuclear [Cu(MET)4(H2O)2]2+ clusters. Complexes 2 and 3 are isostructural with tri-nuclear Cu clusters linked by Keggin anions to construct a 1D chain. The 1- to 3-CPEs show electrocatalytic properties and can also act as nitrite amperometric sensors. Complexes 13 exhibit photocatalytic activities for degradation of MB. Complexes 1–?3 own fluorescence sensing properties for detecting Hg2+ ions.

Graphical abstract

By using an asymmetric ligand three POM-based complexes were constructed. The 1– to 3–CPEs exhibit good electrocatalytic activities and can be used as nitrite amperometric sensors. The title complexes show good photocatalytic activities for degradation of MB. Moreover, complexes 13 can act as fluorescence sensors to selectively detect Hg2+.

  相似文献   
50.
Selective synthesis of uniform single crystalline silver molybdate/tungstate nanorods/nanowires in large scale can be easily realized by a facile hydrothermal recrystallization technique. The synthesis is strongly dependent on the pH conditions, temperature, and reaction time. The phase transformation was examined in details. Pure Ag(2)MoO(4) and Ag(6)Mo(10)O(33) can be easily obtained under neutral condition and pH 2, respectively, whereas other mixed phases of Mo(17)O(47), Ag(2)Mo(2)O(7,) Ag(6)Mo(10)O(33) were observed under different pH conditions. Ag(6)Mo(10)O(33) nanowires with uniform diameter 50-60 nm and length up to several hundred micrometers were synthesized in large scale for the first time at 140 degrees C. The melting point of Ag(6)Mo(10)O(33) nanowires were found to be about 238 degrees C. Similarly, Ag(2)WO(4), and Ag(2)W(2)O(7) nanorods/nanowires can be selectively synthesized by controlling pH value. The results demonstrated that this route could be a potential mild way to selectively synthesize various molybdate nanowires with various phases in large scale.  相似文献   
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