High Contrast and Bright Emission Piezochromic Fluorescence in Organic Crystals via Pressure Modulated Exciton Coupling Effect

2021 ◽  
pp. 2100598
Author(s):  
Zheng Lv ◽  
Zhongwei Man ◽  
Zhenzhen Xu ◽  
Liyuan Fu ◽  
Shuai Li ◽  
...  
Keyword(s):  
Coupling Effect ◽  
Organic Crystals ◽  
High Contrast ◽  
Exciton Coupling ◽  
Bright Emission

scholarly journals How Do Molecular Motions Affect Structures and Properties at Molecule and Aggregate Levels?

2021 ◽  
Author(s):  
Deshuang Tu ◽  
Jianyu Zhang ◽  
Yunxiao Zhang ◽  
Herman H.-Y. Sung ◽  
Lijie Liu ◽  
...  
Keyword(s):  
Single Molecule ◽  
Organic Crystals ◽  
Molecular Motions ◽  
Aggregate State ◽  
Reversible Deformation ◽  
Single Molecule Level ◽  
Weak Intermolecular Interactions ◽  
Structures And Properties ◽  
Intramolecular Motions ◽  
Bright Emission

<p>Experimental and theoretical analysis demonstrated that the active intramolecular motions in the excited state of all molecules at single molecule level imparted them with more twisted structural conformations and weak emission. However, owing to the restriction of intramolecular motions in the nano/macro aggregate state, all the molecules assumed less twisted conformations with bright emission. Synergic strong and weak intermolecular interactions allowed their crystals to undergo reversible deformation, which effectively solved the problem of the brittles of organic crystals, meanwhile imparted them with excellent elastic performance. </p>

scholarly journals How Do Molecular Motions Affect Structures and Properties at Molecule and Aggregate Levels?

2021 ◽  
Author(s):  
Deshuang Tu ◽  
Jianyu Zhang ◽  
Yunxiao Zhang ◽  
Herman H.-Y. Sung ◽  
Lijie Liu ◽  
...  
Keyword(s):  
Single Molecule ◽  
Organic Crystals ◽  
Molecular Motions ◽  
Aggregate State ◽  
Reversible Deformation ◽  
Single Molecule Level ◽  
Weak Intermolecular Interactions ◽  
Structures And Properties ◽  
Intramolecular Motions ◽  
Bright Emission

<p>Experimental and theoretical analysis demonstrated that the active intramolecular motions in the excited state of all molecules at single molecule level imparted them with more twisted structural conformations and weak emission. However, owing to the restriction of intramolecular motions in the nano/macro aggregate state, all the molecules assumed less twisted conformations with bright emission. Synergic strong and weak intermolecular interactions allowed their crystals to undergo reversible deformation, which effectively solved the problem of the brittles of organic crystals, meanwhile imparted them with excellent elastic performance. </p>

Fluorescence of CoTPP Mediated by the Plasmon–Exciton Coupling Effect in the Tunneling Junction

2021 ◽  
pp. 5349-5356
Author(s):  
Yiting Liu ◽  
Yajie Bian ◽  
Yuyi Zhang ◽  
Chao Hang ◽  
Xiaolei Zhang ◽  
...  
Keyword(s):  
Coupling Effect ◽  
Tunneling Junction ◽  
Exciton Coupling

scholarly journals Plasmon–Exciton Coupling Effect on Plasmon Damping

2021 ◽  
pp. 2100281
Author(s):  
Lulu Ye ◽  
Weidong Zhang ◽  
Aiqin Hu ◽  
Hai Lin ◽  
Jinglin Tang ◽  
...  
Keyword(s):  
Coupling Effect ◽  
Exciton Coupling

Interpretation of irradiation-induced changes in electron diffractograms and images of extinction contours at low temperatures

1984 ◽  
Vol 42 ◽  
pp. 268-269
Author(s):  
E. Knapek ◽  
H. Formanek ◽  
G. Lefranc ◽  
I. Dietrich
Keyword(s):  
Low Temperatures ◽  
Carbon Films ◽  
Organic Crystals ◽  
Wide Spread ◽  
Lens System ◽  
Preparation Conditions ◽  
Thin Carbon ◽  
Electron Diffractograms ◽  
Diffraction Patterns ◽  
Induced Changes

A few years ago results on cryoprotection of L-valine were reported, where the values of the critical fluence De i.e, the electron exposure which decreases the intensity of the diffraction reflections by a factor e, amounted to the order of 2000 + 1000 e/nm2. In the meantime a discrepancy arose, since several groups published De values between 100 e/nm2 and 1200 e/nm2 /1 - 4/. This disagreement and particularly the wide spread of the results induced us to investigate more thoroughly the behaviour of organic crystals at very low temperatures during electron irradiation.For this purpose large L-valine crystals with homogenuous thickness were deposited on holey carbon films, thin carbon films or Au-coated holey carbon films. These specimens were cooled down to nearly liquid helium temperature in an electron microscope with a superconducting lens system and irradiated with 200 keU-electrons. The progress of radiation damage under different preparation conditions has been observed with series of electron diffraction patterns and direct images of extinction contours.

Resistance Monitor and Control for Vacuum Evaporation of Metals and Carbon

1976 ◽  
Vol 34 ◽  
pp. 572-573
Author(s):  
Russell L. Steere ◽  
Eric F. Erbe ◽  
J. Michael Moseley
Keyword(s):  
Electronic Device ◽  
Point Sources ◽  
High Contrast ◽  
Variable Resistor ◽  
Quality Of Results ◽  
Low Contrast ◽  
Evaporation Source ◽  
And Control ◽  
At Will

We have designed and built an electronic device which compares the resistance of a defined area of vacuum evaporated material with a variable resistor. When the two resistances are matched, the device automatically disconnects the primary side of the substrate transformer and stops further evaporation.This approach to controlled evaporation in conjunction with the modified guns and evaporation source permits reliably reproducible multiple Pt shadow films from a single Pt wrapped carbon point source. The reproducibility from consecutive C point sources is also reliable. Furthermore, the device we have developed permits us to select a predetermined resistance so that low contrast high-resolution shadows, heavy high contrast shadows, or any grade in between can be selected at will. The reproducibility and quality of results are demonstrated in Figures 1-4 which represent evaporations at various settings of the variable resistor.

Confocal laser microscopy of impregnated central nervous system tissue

1988 ◽  
Vol 46 ◽  
pp. 94-95
Author(s):  
J.N. Turner ◽  
M. Siemens ◽  
D. Szarowski ◽  
D.N. Collins
Keyword(s):  
Electron Microscopy ◽  
Central Nervous System ◽  
Nervous System ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Confocal Laser ◽  
High Contrast ◽  
Central Nervous System Tissue ◽  
Tissue Samples ◽  
Reflected Light

A classic preparation of central nervous system tissue (CNS) is the Golgi procedure popularized by Cajal. The method is partially specific as only a few cells are impregnated with silver chromate usualy after osmium post fixation. Samples are observable by light (LM) or electron microscopy (EM). However, the impregnation is often so dense that structures are masked in EM, and the osmium background may be undesirable in LM. Gold toning is used for a subtle but high contrast EM preparation, and osmium can be omitted for LM. We are investigating these preparations as part of a study to develop correlative LM and EM (particularly HVEM) methodologies in neurobiology. Confocal light microscopy is particularly useful as the impregnated cells have extensive three-dimensional structure in tissue samples from one to several hundred micrometers thick. Boyde has observed similar preparations in the tandem scanning reflected light microscope (TSRLM).

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