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51.
Juechen Ni Yijia Wang Haoke Zhang Jing Zhi Sun Ben Zhong Tang 《Molecules (Basel, Switzerland)》2021,26(2)
Luminogens with aggregation-induced emission (AIEgens) have been widely applied in the field of photodynamic therapy. Among them, aggregation-induced emission photosensitizers (AIE–PSs) are demonstrated with high capability in fluorescence and photoacoustic bimodal imaging, as well as in fluorescence imaging-guided photodynamic therapy. They not only improve diagnosis accuracy but also provide an efficient theranostic platform to accelerate preclinical translation as well. In this short review, we divide AIE–PSs into three categories. Through the analysis of such classification and construction methods, it will be helpful for scientists to further develop various types of AIE–PSs with superior performance. 相似文献
52.
53.
多孔活性金属材料因为内部存在大量的孔隙,大大地增加了与空气的接触面积,使得其在空气中的燃烧较为猛烈,燃烧温度迅速上升。其燃烧过程属于固体燃烧的范畴,较为复杂。以镁为例,通过建立燃烧模型,来研究多孔活性金属的光谱辐射特性。首先,建立氧气总消耗量与活性金属剩余质量的关系,研究氧气在活性金属孔隙内的扩散浓度关系,通过求解活性金属热平衡方程得到活性金属燃烧过程中温度与时间的关系式,进而得到活性金属的峰值光谱辐射强度表达式;然后,将模型计算的仿真结果与红外热像仪测得的实验结果对比,结果表明,模型的计算结果与实验结果相一致,误差在了10%以内;最后,通过建立的燃烧模型来研究活性金属燃烧规律以及其光谱辐射特性,解决了高空、高速下的活性金属光谱辐射强度难以实验获得的问题,大大减小了实验成本与时间。分别对比不同时间活性金属箔片在1~3,3~5以及8~12 μm波段下的辐射强度,得出活性金属燃烧时的辐射强度主要集中在3~5 μm波段的结论。研究结果表明:自燃金属最大燃烧温度随高度的增加逐渐下降,随气流速度的增加先增加后减小,在速度为30 m·s-1时,温度达到最大;自燃金属的光谱辐射强度在2~6 μm波段达到最大。该模型也可以用来研究其他活性金属的燃烧特性。 相似文献
54.
《Comptes Rendus Chimie》2017,20(1):7-19
Me/Ti-PILC catalysts (Me: La, Se, Rb) were prepared with 60% in weight of Ti-species and 3% in weight of Me-secondary species added under ultrasounds. All materials were characterized by XRF, XPS, XRD, BET, HR-TEM/EDS, FEG-SEM and UV-vis. Three kinds of Ti-oxide nanoparticles were identified: (1) Ti-pillars within the clay layers, (2) rutile nanoflowers, and (3) anatase. In UV-vis spectra, no significant change in the band-gap was observed. In La and Se samples, small variations of the anatase XRD lines are associated with cationic diffusion after deposition of secondary species and calcination. An O1s XPS-peak (533.5 eV) is attributed to oxygen vacancies generated by this diffusion. Phosphate photo-removal in water was studied using phosphoric acid solution (75.97 g L−1). Dephosphatation is significantly improved in the presence of Me-species as La/Ti-PILC > Se/Ti-PILC > Rb/Ti-PILC > Ti-PILC. Partial dephosphatation by adsorption is possible in the dark but is strongly improved by UV irradiation. With a La catalyst and under UV irradiation, phosphates (6.6 × 10−3 mol L−1) were recovered in less than 70 min. Therefore, Me/Ti-PILC have a great potential as photocatalysts for the treatment of wastewaters and the recovery of phosphates. 相似文献
55.
《Arabian Journal of Chemistry》2014,7(1):11-25
This article provides a critical review and a wide range of applications of dithiocarbamates (DTCs) in environmental samples. The characteristics of DTCs are reviewed with particular emphasis on inorganic speciation studies using state-of-the-art analytical instrumentation coupled with computational methods of analysis. 相似文献
56.
Exhaled breath condensate is a promising, non-invasive, diagnostic sample obtained by condensation of exhaled breath. Starting from a historical perspective of early attempts of breath testing towards the contemporary state-of-the-art breath analysis, this review article focuses mainly on the progress in determination of non-volatile compounds in exhaled breath condensate. The mechanisms by which the aerosols/droplets of non-volatile compounds are formed in the airways are discussed with methodological consequences for sampling. Dilution of respiratory droplets is a major problem for correct clinical interpretation of the measured data and there is an urgent need for standardization of EBC. This applies also for collection instrumentation and therefore various commercial and in-house built devices are described and compared with regard to their design, function and collection parameters. The analytical techniques and methods for determination of non-volatile compounds as potential markers of oxidative stress and lung inflammation are scrutinized with an emphasis on method suitability, sensitivity and appropriateness. The relevance of clinical findings for each group of possible non-volatile markers of selected pulmonary diseases and methodological recommendations with emphasis on interdisciplinary collaboration that is essential for future development into a fully validated clinical diagnostic tool are given. 相似文献
57.
Environmental Fenton chemistry has been poorly constrained within the marine environment at a multi-component level. A simple, unique, reconfiguration of a flow-injection analytical system combined with luminol chemiluminescence allows quasi-simultaneously the measurement, using a single load-inject valve and a single photon multiplier tube, of reduced iron, Fe(II), and hydrogen peroxide. The system enables rapid, every 22 s, measurements with good accuracy at environmentally relevant concentrations, less than 5% relative standard deviations on both a 5 nM Fe(II) standard and a 60 nM hydrogen peroxide standard. Limits of detection were as low as 40 pM Fe(II) and 100 pM hydrogen peroxide. The system showed excellent capability by measuring from within an organic rich seawater the photochemically induced production of Fe(II) and hydrogen peroxide and their subsequent cycling and Fenton like interactions. 相似文献
58.
《Journal of Coordination Chemistry》2012,65(3):417-426
Abstract The electrochemical behavior of VOQ2OH or [VOQ2-OVOQ2] (Q = 8-hydroxyquinohnate anion) has been investigated by cyclic voltammetry in acetonitnie solutions. Although both species exist simultaneously at every condition analyzed, they can be clearly differentiated by this method. The effect of trace amounts of water on the electrochemical behavior is also discussed. 相似文献
59.
Dr. Chi Kyung Kim Taeho Kim In‐Young Choi Min Soh Dr. Dohoung Kim Young‐Ju Kim Dr. Hyunduk Jang Hye‐Sung Yang Dr. Jun Yup Kim Dr. Hong‐Kyun Park Dr. Seung Pyo Park Sangseung Park Dr. Taekyung Yu Prof. Byung‐Woo Yoon Prof. Seung‐Hoon Lee Prof. Taeghwan Hyeon 《Angewandte Chemie (International ed. in English)》2012,51(44):11172-11172
60.
Wilson Merchan-Merchan Alexei V. Saveliev Walmy Cuello Jimenez 《Proceedings of the Combustion Institute》2011,33(2):1899-1908
In this paper we report the growth of 1-D and 3-D tungsten-oxide nanostructures on tungsten wire probes inserted in an opposed-flow oxy-fuel flame. The probe diameter and oxygen content in the oxidizer were varied to study their influence on the growth of tungsten-oxide nanostructures. The introduction of a 1-mm diameter W probe into the flame environment with an oxidizer composition of 50%O2 + 50%N2, resulted in the formation of 1-D nanorods on the upper surface of the probe. The formation of triangular, rectangular, square, and cylindrical 3-D channels with completely hollow or semi-hollow morphology was achieved by reducing the probe diameter to 0.5 mm. Whereas, the increase of the O2 content to 100% and the employment of a 1-mm probe resulted in the growth of ribbon-like micron-sized structures. The lattice spacing of ∼0.38 nm measured for the 1-D W-oxides closely matches a monoclinic WO3 structure. X-ray photoelectron spectroscopy analysis revealed that the larger 3-D structures also consist of WO3 confirming that the chemical composition of the structures remains the same while varying the probe and flame parameters. The proposed growth mechanism states that the 3-D WO3 structures are formed through the lateral coalescence of 1-D W-oxide nanorods. 相似文献