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51.
M. Bahra D. Elliott M. Reading R. Ryan 《Journal of Thermal Analysis and Calorimetry》1992,38(4):543-555
A novel instrument is described called the Thin film Analyser (TFA) which quantitatively measures changes in mechanical and rheological properties of drying films in-situ on a test panel. It is based around a simple force-sensing device, capable of carrying various probes, which can be positioned in anX-Y plane over the panel. Temperature control is achieved by means of a heating block under the sample. By imposing a thermal gradient along the block, measurements can be obtained at a series of temperatures in a single experiment. Several applications of the TFA to the drying of curable and latex-based coatings are discussed, as well as some more specialized uses. The TFA concept represents a novel approach to the thermal analysis of thin films.The authors gratefully acknowledge the design, engineering and software development work of the Instrument Group at ICI Paints, in particular John Hayton, Neil Burrows, Tony Evans and Ian Francis, who have now built three versions of the TFA. 相似文献
52.
Tianxin Bai Xiaochen Wang Zhongyi Wang Sujun Ji Xuan Meng Qiujie Wang Ruiling Zhang Peigeng Han Prof. Dr. Ke-li Han Dr. Junsheng Chen Feng Liu Bin Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(2):e202213240
Double perovskites (DPs) are one of the most promising candidates for developing white light-emitting diodes (WLEDs) owing to their intrinsic broadband emission from self-trapped excitons (STEs). Translation of three-dimensional (3D) DPs to one-dimensional (1D) analogues, which could break the octahedral tolerance factor limit, is so far remaining unexplored. Herein, by employing a fluorinated organic cation, we report a series of highly luminescent 1D DP-inspired materials, (DFPD)2MIInBr6 (DFPD=4,4-difluoropiperidinium, MI=K+ and Rb+). Highly efficient warm-white photoluminescence quantum yield of 92 % is achieved by doping 0.3 % Sb3+ in (DFPD)2KInBr6. Furthermore, single-component warm-WLEDs fabricated with (DFPD)2KInBr6:Sb yield a luminance of 300 cd/m2, which is one of the best-performing lead-free metal-halides WLEDs reported so far. Our study expands the scope of In-based metal-halides from 3D to 1D, which exhibit superior optical performances and broad application prospects. 相似文献
53.
Dr. Jin Su Dr. Tohru Tsuruoka Dr. Takuji Tsujita Dr. Yuu Inatomi Dr. Kazuya Terabe 《Angewandte Chemie (International ed. in English)》2023,62(9):e202217203
Solid-state batteries (SSBs) that use solid electrolytes instead of flammable liquid electrolytes have the potential to generate higher specific capacity and offer better safety. Magnesium (Mg) based SSBs with Mg metal anodes are considered to be one of the most promising energy storage candidates, because it gives high theoretical volumetric capacities of 3830 mAh cm−3. Here, we demonstrate an atomic layer deposition (ALD) process with a double nitrogen plasma process that successfully produces nitrogen-incorporated magnesium phosphorus oxynitride (MgPON) solid-state electrolyte (SSE) thin films at a low deposition temperature of 125 °C. The ALD MgPON SSEs exhibit an ionic conductivity of 0.36 and 1.2 μS cm−1 at 450 and 500 °C, respectively. The proposed ALD strategy shows the ability of conformal deposition nitrogen-doped SSEs on pattered substrates and is attractive for using nitride ion-conducing films as protective or wetting interlayers in solid-state Mg and Li batteries. 相似文献
54.
Jiahong Yu Zhiyu Sun Huili Ma Chengyun Wang Wenbin Huang Zikai He Wenjun Wu Honglong Hu Weijun Zhao Wei-Hong Zhu 《Angewandte Chemie (International ed. in English)》2023,62(52):e202316647
The development of ultra-long room-temperature phosphorescence (UL-RTP) in processable amorphous organic materials is highly desirable for applications in flexible displays, anti-counterfeiting, and bio-imaging. However, achieving efficient UL-RTP from amorphous materials remains a challenging task, especially with activation by visible light and a bright afterglow. Here we report a general and rational molecular-design strategy to enable efficient visible-light-excited UL-RTP by multi-esterification of a rigid large-plane phosphorescence core. Notably, multi-esterification minimizes the aggregation-induced quenching and accomplishes a ′four birds with one stone′ possibility in the generation and radiation process of UL-RTP: i) shifting the excitation from ultraviolet light to blue-light through enhancing the transition dipole moment of low-lying singlet-states, ii) facilitating the intersystem crossing process through the incorporation of lone-pair electrons, iii) boosting the decay process of long-lived triplet excitons resulting from a significantly increased transition dipole moment, and iv) reducing the intrinsic triplet nonradiative decay by substitution of high-frequency vibrating hydrogen atoms. All these factors synergistically contribute to the most efficient and stable visible-light-stimulated UL-RTP (lifetime up to 2.01 s and efficiency up to 35.4 % upon excitation at 450 nm) in flexible films using multi-esterified coronene, which allows high-tech applications in single-component time-delayed white light-emitting diodes and information technology based on flashlight-activated afterglow encryption. 相似文献
55.
A free standing film of polyaniline as large as 18 cm×18cm×0.002 cm can be obtained by evaporation of a solution of the chemically synthesized base in NMP. Its structure was examined by the elemental analysis, IR, U.V.-visible spectra, XPS, DSC, SEM and X-ray scattering and its conducting behavior as well as electrochemical properties were studied. Results show that the composition, structure of main chain, physical properties of the free standing film of polyanilme is similar to that of the powder. However, some differences in its electronic structure, conductivity at room temperature and potential of redox couple between the flee standing film and powder are observed, which may be due to cross-linking of the film of polyaniline. 相似文献
56.
57.
Xiao-bo Wan Yun Lu Xiao-rong Liu Liang Zhou Shi Jin Gi Xue Department of Polymer Science Engineering the State Key Laboratory of Coordination Chemistry Nanjing University Nanjing China 《高分子科学》1999,(2):99-111
The complexation of thiophene with a Lewis acid with moderate acidity as a solvent, such as BF_3-ethyl ether (BFEE) remarkedly lowered the electrochemical polymerization potential. The positively chargedmetal surface of electrode in the process of electrochemical deposition enhanced the coordination interactionbetween π-electrons of thiophene unit and the metal, which makes thiophene rings lie parallel to the surfaceof electrode, resulting in a highly ordered polymeric structure. Because of the large intra-chain transferintegrals, the transport of charge is believed to be principally along the conjugated chains, which is muchgreater than the inter-chain hopping. The specific electrical resistance across the polythiophene film thicknessis more than 10~4 times than that along the surface plane of the film. In this paper we review the recentdevelopment of polymerization technique by low potential electrochemical method performed in our lab andseveral electrical devices in which the compact polythiophene films, such as anionic and cationic sieves, andlaminate film junction of undoped polythiophene derivatives were used. 相似文献
58.
采用Seemann-Bohlin准聚焦X射线衍射仪测量薄膜厚度的误差理论分析 总被引:1,自引:0,他引:1
本文从理论上分析了衍射强度比偏差Δ(I/I∞)和衍射峰位偏差Δ2θ对Seemann-Bohlin准聚焦X射线衍射仪测量表面单层薄膜厚度误差的影响。分析结果表明,降低Δ(I/I∞)可提高膜厚的测量精度,在Δ(I/I∞)-定的情况下,按μρt[Sin(-1)γ+Sin(-1)(2θ-γ)]=1选择靶辐射和衍射晶面可使由Δ(I/I∞)导致的膜厚测量误差具有极小值;选择高角度衍射线有助于减小试样离焦引起的衍射峰位偏差,亦可降低因衍射角测量偏差导致的膜厚测量误差,当衍射线处于薄膜的法向2θ=γ+π/2时,角度项误差(Δt/t)(2θ)完全消除。 相似文献
59.
60.
Perovskites as Precursors for Ni/La2O3 Catalysts in the Dry Reforming of Methane: Synthesis by Constant pH Co‐Precipitation,Reduction Mechanism and Effect of Ru‐Doping 下载免费PDF全文
Stefanie Kühl Hendrik Düdder Frank Girgsdies Kevin Kähler Martin Muhler Malte Behrens 《无机化学与普通化学杂志》2017,643(16):1088-1095
LaNiO3 perovskite is an interesting precursor for Ni/La2O3 catalysts for the dry reforming of methane at high temperatures. Precursors have been synthesized by co‐precipitation without, with 2.5 at %, and with 5 at % Ru doping. The presence of Ru leads to a stabilization of the perovskite structure and hinders the decomposition into NiO and Ruddlesden‐Popper mixed oxides Lan+1NinO3n+1, which was observed for the Ru‐free sample upon calcination at 1000 °C (n = 3). Upon reduction in hydrogen, a mechanism involving at least two steps was observed and the first major step was identified as the partial reduction of the precursor leading to a LaNiO2.5‐like intermediate. The second major step is the reduction to Ni metal supported on La2O3 independent of the Ru content of the catalyst. In the presence of Ru, indications for Ni‐Ru alloy formation and for a higher dispersion of the metallic phase were found. The catalytic activity in DRM of the catalyst containing 2.5 % Ru was superior to the catalysts with more or without Ru. Furthermore, the propensity of coke formation was reduced by the presence of Ru. 相似文献