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41.
Full Color Emission in ZnGa2O4: Simultaneous Control of the Spherical Morphology,Luminescent, and Electric Properties via Hydrothermal Approach 下载免费PDF全文
Yang Zhang Zhijian Wu Dongling Geng Xiaojiao Kang Mengmeng Shang Xuejiao Li Hongzhou Lian Ziyong Cheng Jun Lin 《Advanced functional materials》2014,24(42):6581-6593
ZnGa2O4 and ZnGa2O4: Mn2+/Eu3+ with uniform nanosphere (diameter about 400 nm) morphology have been synthesized via a facile hydrothermal approach. XRD, Raman spectra, XPS, FT‐IR, SEM, TEM, photoluminescence (PL), and cathodoluminescecne (CL) spectra are used to characterize the resulting samples. The controlled experiments indicate the dosage of trisodium citrate and pH values are responsible for shape determination of the ZnGa2O4 products. The possible fast crystallization–dissolution–recrystallization formation mechanism for these nanospheres is presented. Under UV light and low‐voltage electron beam excitation, ZnGa2O4, ZnGa2O4: Mn2+ and ZnGa2O4: Eu3+ emit bright blue, green, and red luminescence, respectively. Based on density functional theory calculations from first principles, the green and red emission are caused by the Mn 3d and Eu 4f electronic structures, respectively. Besides, the dependence of the CL intensity on the calcination temperature and electrical conductivity of the samples is presented. The ZnGa2O4: Mn2+ nanospheres have a higher CL intensity than that of bulk samples under the same excitation condition. The realization of three primary colors from a single host material suggests that full color display based on ZnGa2O4 nanospheres might be achievable, showing that these materials have potential applications in lighting and display fields. 相似文献
42.
This paper firstly deals with finite time stability (FTS) of Riemann‐Liouville fractional delay differential equations via giving a series of properties of delayed matrix function of Mittag‐Leffler. We secondly study relative controllability of such type‐controlled system. With the help of the representation of solution, both Gram‐like type matrix and rank criterion are derived, which extend the corresponding results for linear systems. 相似文献
43.
In this paper, we present novel integrable symplectic maps, associated with ordinary difference equations, and show how they determine, in a remarkably diverse manner, the integrability, including Lax pairs and the explicit solutions, for integrable partial difference equations which are the discrete counterparts of integrable partial differential equations of Korteweg‐de Vries‐type (KdV‐type). As a consequence it is demonstrated that several distinct Hamiltonian systems lead to one and the same difference equation by means of the Liouville integrability framework. Thus, these integrable symplectic maps may provide an efficient tool for characterizing, and determining the integrability of, partial difference equations. 相似文献
44.
Tian Bai Kongyin Zhao Zijie Lu Xuefang Liu Ze Lin Mengmeng Cheng Ziyi Li Dunwan Zhu Linhua Zhang 《中国化学快报》2021,32(3):1051-1054
Herein,copper ion doped calcium alginate(Cu~(2+)/CaAlg) composite hydrogel filtration membranes were prepared by using natural polymer sodium alginate(NaAlg) as raw material.The thermal stability and structure of the composite membranes were characterized by thermogravimetric analysis and infrared spectroscopy.The mechanical strength,anti-fouling performance,hydrophilicity and filtration performance of the membrane were studied.The results show that Cu~(2+)/CaAlg hydrogel membrane has excelle nt mechanical properties and thermal stability.The anti-swelling ability of the membrane was greatly enhanced by doping Cu~(2+).After three alternate filtration cycles,the flux recovery rate of Cu~(2+)/CaAlg hydrogel membrane can still reach 85%,indicating that the membrane has good antipollution performance.When the operation pressure was 0.1 MPa,the rejection of coomassie brilliant blue G250 reached 99.8% with a flux of 46.3 L m ~2 h ~1,while the Na_2 SO_4 rejection was less than 10.0%.The Cu~(2+)/CaAlg membrane was recycled after 24 h in the filtration process,and its flux and rejection rate did not decrease significantly,indicating that the hydrogel membrane has long-term application potential.The Cu~(2+)/CaAlg membrane has a wide range of applications prospect in dye desalination,fine separation and biopharmaceutical technology fields. 相似文献
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在氩气气氛中900℃煅烧前驱物MoS2核壳超级球得到MoS2核壳球。在升温速率为20、10、5、2℃·min-1时,MoS2核壳球上氧掺杂量分别从前驱物的23.1%降低到17.6%、10.8%、5.5%、6.2%。结果表明较低的升温速率可以导致更低的氧掺杂量。基于前驱物特殊的准分子超晶格结构,提出了原位阴离子交换反应机理,以深入理解MoS2核壳球上氧掺杂的动力学调制机理。电化学性能研究表明通过调制氧掺杂量可以有效改善MoS2核壳球电化学分解水的性能。 相似文献
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48.
Baiji Xue Yanhua Yu Guoqiang Peng Mengmeng Sun Peng Lv Xuefeng Li 《Molecules (Basel, Switzerland)》2022,27(10)
Amphotericin B (AMB) is an antifungal drug used for serious fungal infections. However, AMB has adverse reactions such as nephrotoxicity, which limit the clinical application of AMB alone or in combination with other antifungal drugs. Nano or micro drug delivery systems (DDS) have been proven to be effective in reducing the toxic and side effects of drugs. Further, the combination of AMB with other compounds with antifungal activity, such as curcumin (CM), may enhance the synergistic effects. Herein, AMB and CM were co-loaded into porous poly (lactic-co-glycolic acid) (PLGA) microparticles (MPs) to prepare AMB/CM-PLGA MPs. The AMB/CM-PLGA MPs showed a remarkably reduced hemolysis (62.2 ± 0.6%) compared to AMB (80.9 ± 1.1%). The nephrotoxicity of AMB/CM-PLGA MPs is significantly lower than that of AMB. In vitro, AMB/CM-PLGA MPs had better inhibitory effects on the adhesion and biofilm formation of Candida albicans compared with AMB. Experiments on mice infected with C. albicans showed that AMB/CM-PLGA MPs have a better therapeutic effect than AMB in vivo. In summary, AMB/CM-PLGA MPs may be a novel and promising therapeutic candidate for fungal infection. 相似文献
49.
大花无柱兰是一种珍稀兰科植物,具有一定的观赏和药用价值,但数量十分稀少,该物种亟待保护。本研究采用SRAP分子标记技术,对10个居群的115份DNA样品进行PCR扩增,并开展遗传多样性分析。从81对引物中筛选出9个条带清晰、多态性好、重复性高的引物组合,共扩增得到305条谱带。在物种水平上,多态性比率(PPB)为100%,Nei’s基因多样性指数(H )为0.209 8,Shannon’s指数(I )为0.340 2;在居群水平上,PPB为24.59%~52.13%,H 为0.079 6~0.165 5,I 为0.120 9~0.252 3。居群水平上,基因分化度(Gst)为0.520 9,基因流(Nm)为0.459 9,遗传距离为0.091 9~0.198 4。UPGMA聚类结果表明,10个居群可分为3大类,地理距离相近的居群优先聚集。大花无柱兰的遗传多样性较为丰富,居群间存在一定的遗传分化和基因交流,可采用就地保护和人工栽培等方式加以保护。 相似文献
50.
Group-invariant solutions, non-group-invariant solutions and conservation laws of Qiao equation 下载免费PDF全文
This paper considers a completely integrable nonlinear wave equation which is called Qiao equation. The equation is reduced via Lie symmetry analysis. Two classes of new exact group-invariant solutions are obtained by solving the reduced equations. Specially, a novel technique is proposed for constructing group-invariant solutions and non-group-invariant solutions based on travelling wave solutions. The obtained exact solutions include a set of traveling wave-like solutions with variable amplitude, variable velocity or both. Nonlocal conservation laws of Qiao equation are also obtained with the corresponding infinitesimal generators. 相似文献