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991.
Rod-shaped mesoporous titanosilicate composites (RMTSs) with controllable aspect ratios (ARs) were fabricated using cetyltrimethylammonium bromide (CTAB) and ammonium hydroxide (NH4OH) at a continuous stirring rate, resulting in ARs ranging from 1 to 5. Slowing the stirring rate or increasing the concentration of CTAB mainly impacted the length growth, whereas NH4OH affected the width growth. Photocatalytic activity studies revealed that the length of RMTSs played a more significant role than the width at lower ARs in their photocatalytic activity.  相似文献   
992.
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995.
Complex metal–organic frameworks used as precursors allow design and construction of various nanostructured functional materials which might not be accessible by other methods. Here, we develop a sequential chemical etching and sulfurization strategy to prepare well-defined double-shelled zinc–cobalt sulfide (Zn-Co-S) rhombic dodecahedral cages (RDCs). Yolk-shelled zinc/cobalt-based zeolitic imidazolate framework (Zn/Co-ZIF) RDCs are first synthesized by a controlled chemical etching process, followed by a hydrothermal sulfurization reaction to prepare double-shelled Zn-Co-S RDCs. Moreover, the strategy reported in this work enables easy control of the Zn/Co molar ratio in the obtained double-shelled Zn-Co-S RDCs. Owing to the structural and compositional benefits, the obtained double-shelled Zn-Co-S RDCs exhibit enhanced performance with high specific capacitance (1266 F g−1 at 1 A g−1), good rate capability and long-term cycling stability (91 % retention over 10,000 cycles) as a battery-type electrode material for hybrid supercapacitors.  相似文献   
996.
A dense and stable inorganic‐organic hybrid with distorted cubic [Gd4O4] units as building blocks bridged by in situ generated sulfate and oxalate was synthesized. Magnetic measurements indicate that the title complex features a ?ΔSmmax=51.49 J kg?1 K?1, which is among the highest values reported so far.  相似文献   
997.
IntroductionAbstract:Anewmethodforthedeterminationofceriumsubgrouprareearthswasstudiedandreportedinthispaper.ItwasfoundthaiceriumsubgrouprareearthelementsreactwithDBMCSAin0.6mol/Lhydrochloricacidmediumtol'ormstablebluecomplexes.Theabsorbancesofequalamountsofceriumsubgrouprareearthsareclosetoeachotherattheirmaximumadsorptivewavelength(641"m).Beer'slawisobeyedfor0-20igofrareearthsin25mlofsolution.Themethodhasbeenappliedtothedeterminationofthetotalamountofceriumsubgrouprareearthsinsteelandcas…  相似文献   
998.
Five morpholino-quinazoline derivatives have been investigated voltammetrically using a competition with the tris(o-phenanthroline) cobalt(III) redox marker for the accumulation at dsDNA modified screen-printed electrodes. An association of quinazolines with DNA was observed at the modified electrodes polarized by the negative potential of –0.4 V vs. Ag/AgCl. This was confirmed by a potentiometric stripping analysis based on the DNA guanine signal. Calibration curves for quinazolines within a concentration range of μmol/L were obtained with DP voltammetry using 5 × 10–7 mol/L Co(phen)3 3+ marker. The quinazolines exhibit no effect on the DNA complex with the fluorescent thiazole orange derivative TO-PRO-3. The role of the accumulation potential in the association interaction with DNA is discussed.  相似文献   
999.
通过对谐振腔镜镀制合理的激光薄膜,成功实现了LD泵浦Nd∶YAG1.112μm激光谱线的运转.利用LBO腔内倍频Nd∶YAG/Cr∶YAG结构获得了高重复频率被动调Q556nm全固态黄光激光器,在注入泵浦功率为1.6W时,得到平均功率51mW,脉冲宽度48ns,重复频率8.9kHz,峰值功率高达119W的脉冲黄光输出.  相似文献   
1000.
A polarization modulator based on splitting with a Savart plate and rotation of an analyzer for a moirésystem with grating imaging is presented, and its modulation principle is analyzed.  相似文献   
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