Stimuli-Responsive Room-Temperature N-Heteroacene Liquid: In Situ Observation of the Self-Assembling Process and Its Multiple Properties

ABSTRACTTiNi shape memory alloy (SMA) has potential applications for nuclear reactors and its phase stability under irradiation is becoming an important topic. Some irradiation-induced diffusion-dependent phase transformations, such as amorphization, have been reported before. In the present work, the behavior of diffusion-independent phase transformation in TiNi SMA was studied by electron irradiation at room temperature. The effect of irradiation on the martensitic transformation of TiNi shape memory alloys was studied by Transmission Electron Microscopy (TEM) with in-situ observation and differential scanning calorimeter (DSC). The results of TEM and DSC measurements show that the microstructure of samples is R phase at room temperature. Electron irradiations were carried out using several different TEM with accelerating voltage of 200 kV, 300 kV, 400 kV and 1000 kV. Also the accelerating voltage in the same TEM was changed to investigate the critical voltage for the effect of irradiation on phase transformation. It was found that a phase transformation occurred under electron irradiation above 320 kV, but never appeared at 300 kV or lower accelerating voltage. Such phase transformation took place in a few seconds of irradiation and was independent of atom diffusion. The mechanism of Electron-irradiation-induced the martensitic transformation due to displacements of atoms from their lattice sites produced by the accelerated electrons.

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Crystallographic Features of the A-Type and CE-Type Antiferromagnetic States in the Simple-Perovskite Manganite System Sr1-xNdxMnO3

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.409.532 ◽

2011 ◽

Vol 409 ◽

pp. 532-537

Author(s):

Yusuke Onezawa ◽

Yasuhide Inoue ◽

Masazumi Arao ◽

Yasumasa Koyama

Keyword(s):

Room Temperature ◽

Three Dimensional ◽

Electronic System ◽

Paramagnetic State ◽

Heating Process ◽

In Situ Observation ◽

Perovskite Manganite ◽

Transmission Electron ◽

Highly Correlated

The electronic states of Sr1-xNdxMnO3 with the simple perovskite structure are characterized by a three-dimensional highly-correlated electronic system. To understand the detailed features of the A-and CE-type antiferromagnetic states in this system, their crystallographic features for x = 0.47, 0.48, and 0.50 have been investigated mainly by both x-ray powder diffraction and transmission electron microscopy. It was found at room temperature that the crystal structure for x = 0.47 was determined to have the monoclinic C2/m symmetry, while the orthorhombic Imma structure was confirmed for x = 0.48 and 0.50. The in-situ observation for x = 0.47 indicated that, in the heating process from room temperature, the C2/m-to-Imma transition occurred in the paramagnetic state, and that the A-type antiferromagnetic state appeared below about 200 K on cooling. In addition, the cooling from room temperature for x = 0.48 and 0.50 resulted in the direct transitions from the orthorhombic Imma state to the A-and CE-type antiferromagnetic states, respectively. Based on these features, we simply discussed the physical origin of the appearance of the paramagnetic state with the monoclinic symmetry for x = 0.47.

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Ferro-Self-Assembly: Magnetic and Electrochemical Adaptation of a Multiresponsive Zwitterionic Metalloamphiphile Showing a Shape-Hysteresis Effect

10.26434/chemrxiv.12370406 ◽

2020 ◽

Author(s):

Stefan Bitter ◽

Moritz Schlötter ◽

Markus Schilling ◽

Rainer Winter ◽

Sebastian Polarz

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Self Assembly ◽

Hysteresis Effect ◽

The Self ◽

Stimuli Responsive ◽

Tubular Aggregates ◽

Optical Birefringence ◽

Sufficient Concentration

We report on a novel multi-stimuli-responsive amphiphile, 1-(Z)-heptenyl-1’-dimethylammonium-methyl-(3-sulfopropyl)ferrocene (6), whose self-assembly properties can be altered by three different stimuli, namely: (i) the addition of external salts which serve to unfold the sultone headgroup, thus triggering self-assembly of 6 into vesicles; (ii) oxidation to 6+, which changes the lipophilic ferrocene to a hydrophilic ferrocenium entity, thereby broadening the size-distribution of the aggregates; and (iii) exposition of 6+ to an external magnetic field of 0.8 T. Under thease conditions and at sufficient concentration, 6+ forms large, tubular aggregates with lengths of up to 15 µm, which persist for over 5 min after the field is switched off again. 6+ is thus the first amphiphile to exhibit a shape-hysteresis effect. The self-assembly/disassembly processes and their dynamics were studied live and in situ by optical birefringence measurements coupled to light scattering.

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In situ and dynamic monitoring of the self-assembling and redox processes of a ferrocenylundecanethiol monolayer by electrochemical quartz crystal microbalance

Langmuir ◽

10.1021/la00041a023 ◽

1992 ◽

Vol 8 (5) ◽

pp. 1385-1387 ◽

Cited By ~ 115

Author(s):

Katsuaki Shimazu ◽

Ichizo Yagi ◽

Yukari Sato ◽

Kohei Uosaki

Keyword(s):

Quartz Crystal Microbalance ◽

Quartz Crystal ◽

Electrochemical Quartz Crystal Microbalance ◽

The Self ◽

Dynamic Monitoring ◽

Redox Processes ◽

Self Assembling

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All-or-none switching of photon upconversion in self-assembled organogel systems

Faraday Discussions ◽

10.1039/c6fd00170j ◽

2017 ◽

Vol 196 ◽

pp. 305-316 ◽

Cited By ~ 19

Author(s):

Pengfei Duan ◽

Deepak Asthana ◽

Takuya Nakashima ◽

Tsuyoshi Kawai ◽

Nobuhiro Yanai ◽

...

Keyword(s):

Self Assembly ◽

Room Temperature ◽

Stimuli Responsive ◽

Molecular Systems ◽

Controlled Assembly ◽

Outstanding Problem ◽

Self Assembling ◽

New Strategy ◽

Donor Acceptor

Aggregation-induced photon upconversion (iPUC) based on a triplet–triplet annihilation (TTA) process is successfully developed via controlled self-assembly of donor–acceptor pairs in organogel nanoassemblies. Although segregation of donor from acceptor assemblies has been an outstanding problem in TTA-based UC and iPUC, we resolved this issue by modifying both the triplet donor and aggregation induced emission (AIE)-type acceptor with glutamate-based self-assembling moieties. These donors and acceptors co-assemble to form organogels without segregation. Interestingly, these donor–acceptor binary gels show upconversion at room temperature but the upconversion phenomena were lost upon dissolution of the gels on heating. The observed changes in TTA-UC emission were thermally reversible, reflecting the controlled assembly/disassembly of the binary molecular systems. The observed on/off ratio of UC emission was much higher than that of the aggregation-induced fluorescence of the acceptor, which highlights the important role of iPUC, i.e., multi-exciton TTA for photoluminescence switching. This work bridges iPUC and supramolecular chemistry and provides a new strategy for designing stimuli-responsive upconversion systems.

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Structural and Optical Properties of β-FeSi2/Si(100) Prepared by Laser Ablation Method

MRS Proceedings ◽

10.1557/proc-478-273 ◽

1997 ◽

Vol 478 ◽

Cited By ~ 7

Author(s):

H. Kakemoto ◽

Y. Makita ◽

A. Obara ◽

Y. Tsai ◽

S. Sakuragi ◽

...

Keyword(s):

Laser Ablation ◽

Room Temperature ◽

Horizontal Gradient ◽

In Situ Observation ◽

X Ray Diffraction ◽

Energy Devices ◽

Laser Ablation Method ◽

Semiconducting Properties ◽

Morphology Characterization

Abstractβ-FeSi2 is a promising material for the application of various electronic, optoelectronic and energy devices. We present here the semiconducting properties of β-FeSi2 films on Si(100) substrate prepared by laser ablation method. Samples were grown using poly-crystalline bulk β-FeSi2 prepared by horizontal gradient freeze method. For the monitoring of growth, in-situ observation of ablation plume was made through fluorescence spectroscopy. Reflection of highenergy electron beam diffraction (RHEED) was also made in-situ to see the surface morphology. Characterization of the films by X-ray diffraction presented purely P3(220) orientation. Raman scattering measurements at room temperature also indicated that the grown films are semiconducting β-FeSi2. Optical absorption spectra at room temperature showed absorption coefficient higher than 105 cm−1 above the band-gap (˜1.2 eV). It was revealed that high quality semiconducting β-FeSi2 films can be fabricated by laser ablation method without post-annealing.

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Dynamic in situ observation of voltage-driven repeatable magnetization reversal at room temperature

Scientific Reports ◽

10.1038/srep23696 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 14

Author(s):

Ya Gao ◽

Jia-Mian Hu ◽

C. T. Nelson ◽

T. N. Yang ◽

Y. Shen ◽

...

Keyword(s):

Magnetization Reversal ◽

Room Temperature ◽

In Situ Observation

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In-situ Observation of CO2 through the Self-purging in Alkaline Membrane Fuel Cell (AMFC)

ECS Transactions ◽

10.1149/1.3271358 ◽

2019 ◽

Vol 19 (31) ◽

pp. 23-27 ◽

Cited By ~ 31

Author(s):

Kenji Fukuta ◽

Hiroshi Inoue ◽

Shin Watanabe ◽

Hiroyuki Yanagi

Keyword(s):

Fuel Cell ◽

The Self ◽

In Situ Observation ◽

Alkaline Membrane Fuel Cell ◽

Alkaline Membrane

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