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51.
AbstractAmino-functionalized mesoporous silica nanoparticles (AFMSN) were prepared based on the self-assembly process of the pre-fabricated template of anionic gemini surfactant. The perfect mass ration of the reactants for the synthesis of the AFMSN with high surface area and amino loading was optimized by orthogonal experiments. Adsorption capability of the optimized product for lead ion (Pb2+) was investigated in detail. Specially, the effects of the amino content, solution pH, adsorbent dosage, temperature, and interference of other metal ions on the removal efficiency of Pb2+ were studied. It is found that these factors can greatly affect the removal efficiency of Pb2+ and the prepared adsorbent exhibits the high adsorption selectivity for Pb2+. At an optimal condition, the AFMSN adsorbent presents an excellent adsorption capacity for Pb2+ up to 211.42?mg/g. The adsorption kinetics study revealed that the pseudo-second-order model could well describe the Pb2+ adsorption process, and the adsorption isotherm was fitted well with the Langmuir model. More importantly, the AFMSN adsorbent could be recycled 8 times and a high adsorption efficiency of Pb2+ could still be maintained. Therefore, the prepared AFMSN adsorbent may find practical application in removing Pb2+ from the polluted water. 相似文献
52.
Hongfan Guo Haiyan Lin Jiqiao Zhang Liufang Yu 《Journal of Dispersion Science and Technology》2013,34(5):706-710
Multi‐walled carbon nanotube (MWCNT)/polythiophene (PTh) composites have been prepared by in situ chemical oxidative polymerization. PTh is synthesized onto the sidewalls of the MWCNTs, which play a role as hard templates for PTh to produce one‐dimensional nanostructures. The morphology and structures of the MWCNT/PTh composites are characterized by High‐resolution transmission electron microscopy, x‐ray diffraction, and Fourier transform infrared spectrometry. Their electrical property and thermal stability are determined using vector network analyzer and thermal gravimetric analyzer. Moreover, the mechanism of MWCNT/PTh nanowire formation is described. The studies show that the composites are nanowires with core‐shell structure, in which the outer shells and inner cores are formed by PTh and MWCNTs, respectively. The addition of MWCNTs does not change the backbone structure of PTh and affect the amorphous condition of PTh very slightly, however, it improves the electrical conductivity and thermal stability of PTh. 相似文献
53.
Dr. Weihui Ou Junda Shen Dr. Fucong Lyu Xufen Xiao Dr. Binbin Zhou Prof. Jian Lu Dr. Yang Yang Li 《化学:亚洲杂志》2021,16(16):2249-2252
Morphologically and dimensionally controlled growth of Ag nanocrystals has long been plagued by surfactants or capping agents that complicate downstream applications, unstable Ag salts that impaired the reproducibility, and multistep seed injection that is troublesome and time-consuming. Here, we report a one-pot electro-chemical method to fast (∼2 min) produce Ag nanoparticles from commercial bulk Ag materials in a nitric acid solution, eliminating any need for surfactants or capping agents. Their size can be easily manipulated in an unprecedentedly wide range from 35 to 660 nm. Furthermore, the Ag nanoparticles are directly grown on the Ag substrate, highly desirable for promising applications such as catalysis and plasmonics. The mechanistic studies reveal that the concentration of Ag+ in the diffusion layer nearby the surface, controlled by the magnitude and duration of voltage, is critical in governing the nanoparticle formation (<1.3 mM) and its dimensional adjustability. 相似文献
54.
Zhao JF Ou HW Wu G Xie BP Zhang Y Shen DW Wei J Yang LX Dong JK Arita M Namatame H Taniguchi M Chen XH Feng DL 《Physical review letters》2007,99(14):146401
The electronic structure of a new charge-density-wave system or superconductor, 1T-Cu(x)TiSe(2), has been studied by photoemission spectroscopy. A correlated semiconductor band structure is revealed for the undoped case, which resolves a long-standing controversy in the system. With Cu doping, the charge-density wave is suppressed by the raising of the chemical potential, while the superconductivity is enhanced by the enhancement of the density of states, and possibly suppressed at higher doping by the strong scattering. 相似文献
55.
56.
We examined the thermal stability of amorphous silicon oxycarbide (SiOC) and crystalline Fe composite by in situ and ex situ annealing. The Fe/SiOC multilayer thin films were grown via magnetron sputtering with controlled length scales on a surface-oxidized Si (100) substrate. These Fe/SiOC multilayers were in situ or ex situ annealed at temperature of 600 °C or lower. The thin multilayer sample (~10 nm) was observed to have a layer breakdown after 600 °C annealing. Diffusion starts from low groove angle triple junctions in Fe layers. In contrast, the thick multilayer structure (~70 nm) was found to be stable and an intermixed layer (FexSiyOz) was observed after 600 °C annealing. The thickness of the intermixed layer does not vary as annealing time goes up. The results suggest that the FexSiyOz layer can impede further Fe, Si and O diffusion, and assists in maintaining morphological stability. 相似文献
57.
Wei-Jie Ou Chen-Shan Kao Yih-Shing Duh Jing-Ming Hsu 《Journal of Thermal Analysis and Calorimetry》2014,116(3):1111-1116
Thermal instability of lithiated cathode materials with organic carbonate were investigated using DSC. Lithium transition metal oxides of LiFePO4, LiMn2O4, and LiCoO2 were mixed with diethyl carbonate, dimethyl carbonate, ethylene carbonate, ethyl methyl carbonate, and propylene carbonate then dynamically screened to about 500 °C. Curves were acquired and analyzed to determine exothermic onset temperatures and reaction enthalpies. These data for assessing the thermal hazards of lithium-ion batteries under discharged conditions were compared to those data published in the literature. 相似文献
58.
Pingchun Wei Kai Zhang Dr. Xin Li Deying Meng Prof. Dr. Hans Ågren Prof. Dr. Zhongping Ou Prof. Dr. Seikweng Ng Prof. Dr. Hiroyuki Furuta Prof. Dr. Yongshu Xie 《Angewandte Chemie (International ed. in English)》2014,53(51):14069-14073
The first neo‐confused hexaphyrin(1.1.1.1.1.0) was synthesized by oxidative ring closure of a hexapyrrane bearing two terminal “confused” pyrroles. The new compound displays a folded conformation with a short interpyrrolic C???N distance of 3.102 Å, and thus it readily underwent ring fusion to afford a neo‐fused hexaphyrin with an unprecedented 5,5,5,7‐tetracyclic ring structure. Furthermore, coordination of CuII triggered a ring opening/contracting reaction to afford a CuII complex of an N‐linked pentaphyrin derivative. The roles of reactive N? C bonds in the porphyrinoid macrocycles were demonstrated. 相似文献
59.
60.
Yufei Shu Dr. Xing Lin Dr. Haiyan Qin Zhuang Hu Prof. Yizheng Jin Prof. Xiaogang Peng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(50):22496-22507
This article offers a materials-chemistry perspective for colloidal quantum dots (QDs) in the field of display, including QD-enhanced liquid-crystal-display (QD-LCD) and QD-based light-emitting-diodes (QLEDs) display. The rapid successes of QDs for display in the past five years are not accidental but have a deep root in both maturity of their synthetic chemistry and their unique chemical, optical, and optoelectronic properties. This article intends to discuss the natural match of QD emitters for display and chemical means to eventually bring about their full potential. 相似文献