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991.
Zhou M Bao J Tao M Zhu R Zeng Y Wei Z Xie Y 《Chemical communications (Cambridge, England)》2012,48(28):3439-3441
The alternate dielectric component is introduced into a nanowall skeleton for the first time. As a photoelectrode, this novel model can optimize the process of photon absorption, charge separation/migration and surface reaction, resulting in superior photoelectrochemical performance. 相似文献
992.
Xin‐Bao Han Zhi‐Ming Zhang Zhi‐Shu Wang Huan Zhang Hui Duan En‐Bo Wang 《ChemInform》2012,43(22):no-no
K2NaH2 [BW12O40]·12H2O, prepared by the conventional aqueous method, is characterized by single crystal XRD and IR spectroscopy. 相似文献
993.
994.
Trypsin was immobilized on cellulose-coated glass fibers via a condensation reaction between the aldehyde groups of the oxidized cellulose and the primary amino groups of trypsin. A piece of the modified fiber was inserted into the main channel of a poly(methyl methacrylate) microchip to form a microfluidic proteolytic bioreactor. Scanning electron microscopy of the cross section of the fiber revealed a rough film on the surface of the fiber glass. The performance of the bioreactor was demonstrated by the tryptic digestion of hemoglobin and cytochrome c, where the time for digestion was reduced to <10?s. The digests were identified by MALDI-TOF-MS to obtain peptide mass fingerprint spectra. The results indicated that the digestion in the microfluidic bioreactor is comparable to that of a 12-h solution tryptic digest and thus provides a promising platform for the high throughput identification of proteins. Figure
Covalent immobilization of trypsin on oxidized cellulose-coated glass fiber cores in microchip for highly efficient proteolysis 相似文献
995.
Yan Xiaoju Bao Ruiling Yu Shuili 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(8):1318-1325
The article studies on the effects of six inorganic ions (Ca2+, Mg2+, Cl?, SO 4 2? , H2PO 4 ? , and HCO 3 ? ) on titanium dioxide (TiO2)-based photocatalytic degradation of humic acid (HA). We focus on the effects of the inorganic ions on HA characters, adsorption of HA on TiO2 and photocatalytic degradation of HA. The results indicate that Ca2+ and Mg2+ with HA can form complexes which can decrease the solubility of HA, and then increase the HA adsorbed on TiO2. However, the complex is more difficult to be degraded than HA. The effects of Cl? and SO 4 2? are closely related to their influences on HA solubility. The solubility changes of HA to some extent can enhance the adsorption of HA on TiO2, and promote the photocatalytic degradation. Nevertheless, great solubility decreasing of HA can weaken the photocatalytic degradation. HCO 3 ? and H2PO 4 ? can inhibit the photocatalytic degradation process seriously, because HCO 3 ? and H2PO 4 ? are the strong scavengers of hydroxyl radicals, and can weaken the adsorption of HA on TiO2 due to adsorption competition. 相似文献
996.
Bao Din Kuok Nguen M. S. Chernov’yants I. V. Burykin A. S. Anokhin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(12):1898-1902
The possibility of applying activated carbon and polymeric sorbents poly(4-vinylpyridine), polytrimethylsilylpropyne (PTMSP), bromo-substituted PNMSP (Br-PNMSP), poly(N-methyl-4-vinylpyridinium iodide) for the sorption recovery of iodine from a 0.5 M solution of sodium chloride is studied. The dependence of iodine sorption on the pH of solution, the amount of adsorbent, and the duration of contact between the solution and adsorbent is studied. The highest sorption capacity (G = 616.78 mg/g) is attained by using poly(N-methyl-4-vinylpyridinium iodide) anionite with the addition of iodine to form complex triiodide ions. The dynamics of iodine adsorption on poly(4-vinylpyridine) is described by a kinetic model of pseudosecond order. The composition and structure of the iodine compounds sorbed by polymers and activated carbon are studied by Raman spectroscopy (RS). 相似文献
997.
A series of anticancer prodrugs with different chemical functional groups were prepared, in which the styryl conjugated 2-nitrobenzyl derivatives were introduced as the phototrigger to regulate the drug (chlorambucil) release. Compared to the common 4,5-dimethoxy-2-nitrobenzyl caged compounds, most of the prodrugs exhibited large and redshifted one-photon absorption within the visible range. One-photon excitation for the drug release was studied by measuring UV-vis absorption, FT-IR, and HPLC spectra, which suggested that chlorambucil was released effectively and precisely by manipulating external light conditions. And the introduction of different functional groups made this type of prodrug a good platform to further react with some typical drug carriers and to further form excellent visible light responsive drug delivery systems. Moreover, the drug also could be effectively released under the excitation of two-photon at 800 nm with comparable photorelease efficiencies. 相似文献
998.
本文讨论了极限圆型Hamilton算子乘积的自伴性,利用Calkin方法及奇异Hamilton系统自伴扩张的一般构造理论,给出了在极限圆型时判定Hamilton算子乘积自伴的一个充要条件. 相似文献
999.
1000.
Yagang Chen Chengfang Liu Hongkun Tian Cheng Bao Xiaojie Zhang Donghang Yan Yanhou Geng Fosong Wang 《Macromolecular rapid communications》2012,33(20):1759-1764
Two conjugated polymers (CPs) P‐tCzC12 and P‐tCzC16 comprising alternating dithieno[3,2‐b:6,7‐b]carbazole and 4,4′‐dihexadecyl‐2,2′‐bithiophene units have been designed and synthesized. Upon thermal annealing, they can form ordered thin films in which the polymer backbones dominantly adopted an edge‐on orientation respective to the substrate with a lamellar spacing of ≈24 Å and a π‐stacking distance of ≈3.7 Å. Organic thin‐film transistors (OTFTs) were fabricated by solution casting. A hole mobility of 0.39 cm2 V−1s−1 has been demonstrated with P‐tCzC16. This value is the highest among the CPs containing heteroacenes larger than 4 rings. 相似文献