Responsive Organoboranes with Dynamic Conformation of Octacyclophane-Type Scaffolds: Synthesis, AIE and Temperature-Dependent Dual Emissions

2021 ◽  
Author(s):  
Kai Zhang ◽  
Guangqian Ji ◽  
Niu Zhang ◽  
Nan Wang ◽  
Xiaodong Yin ◽  
...  
Keyword(s):  
Smart Materials ◽  
Organic Materials ◽  
Design Strategy ◽  
Temperature Dependent ◽  
Dual Emissions

In the field of synthetic organic materials, there is still an urgent demand for new smart materials that show great potential in diverse applications. We herein describe a design strategy...

scholarly journals Design of Mechanically Flexible Organic Crystals: A Crystal Engineering Approach

2014 ◽  
Vol 70 (a1) ◽  
pp. C648-C648
Author(s):  
Gamidi Krishna ◽  
Ramesh Devarapalli ◽  
Garima Lal ◽  
C. Reddy
Keyword(s):  
Crystal Structures ◽  
Organic Solar Cells ◽  
Crystal Engineering ◽  
Rational Design ◽  
Organic Materials ◽  
Building Blocks ◽  
Design Strategy ◽  
High Plasticity ◽  
Simple Strategy ◽  
Slip Planes

Utilization of organic single crystal materials is increasing day by day owing to their promising applications in organic light emitting diodes [1], organic solar cells, mechanochromic luminescence [2] and tablatability [3] of APIs etc. These desirable functions, especially mechanical properties, can be achieved by imparting soft nature in organic materials, however unfortunately there is no simple strategy to attain this. Till date all the findings are serendipitous discoveries, so a rational design strategy is necessary to accomplish such soft mechanical behavior in molecular crystals. Here we propose a design strategy to attain plastically deformable organic materials by introducing slip planes in the crystal structures. The high plasticity can be achieved by introducing hydrophobic groups, such as t-Bu, -OMe, -Me and multiple –Cl (or) –Br groups on -Ar building blocks, for example on naphthalene diimide (NDI), which leads to the formation of slip planes in the crystal structures (as shown in attached figure), hence facilitate the plastic (irreversible) bending [2].

Organic Materials for Active Layers in Transistors: Study of the Electrical Stability Properties

2006 ◽  
Vol 514-516 ◽  
pp. 33-37
Author(s):  
Henrique Leonel Gomes ◽  
Peter Stallinga ◽  
D.M. de Leeuw
Keyword(s):  
Field Effect ◽  
Organic Materials ◽  
Field Effect Transistors ◽  
Trap States ◽  
Electrical Stability ◽  
Temperature Dependent ◽  
Electrical Instability ◽  
Active Layers ◽  
Trapping Process ◽  
Trapping Sites

Field effect transistors based on several conjugated organic materials were fabricated and assesed in terms of electrical stability. The device characteristics were studied using steady state measurements as well as techniques for addressing trap states. Temperature-dependent measurements show clear evidence for an electrical instability occurring above 200 K that is caused by an electronic trapping process. It is suggested that the trapping sites are created by a change in the organic conjugated chain, a process similar to a phase transition.

Precise molecular design for BN-modified polycyclic aromatic hydrocarbons toward mechanochromic materials

2020 ◽  
Vol 8 (42) ◽  
pp. 22023-22031
Author(s):  
Huanan Huang ◽  
Ying Zhou ◽  
Yawei Wang ◽  
Xiaohua Cao ◽  
Chuan Han ◽  
...  
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
Smart Materials ◽  
Molecular Design ◽  
Molecular Level ◽  
Design Strategy ◽  
Material Base ◽  
Polycyclic Aromatic ◽  
Level Design ◽  
Boron Nitrogen

This paper reports on a novel molecular-level design strategy to achieve a novel MCL material base on boron and nitrogen aromatics. The introduction of boron nitrogen unit is the key to design the MCL smart materials.

A design strategy for intramolecular singlet fission mediated by charge-transfer states in donor–acceptor organic materials

2015 ◽  
Vol 14 (4) ◽  
pp. 426-433 ◽  
Author(s):  
Erik Busby ◽  
Jianlong Xia ◽  
Qin Wu ◽  
Jonathan Z. Low ◽  
Rui Song ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Organic Materials ◽  
Design Strategy ◽  
Singlet Fission ◽  
Donor Acceptor

scholarly journals Temperature-Dependent Viscosity of Organic Materials Characterized by Atomic Force Microscope

Atmosphere ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1476
Author(s):  
Yiming Qin ◽  
Jianhuai Ye ◽  
Paul Ohno ◽  
Theodora Nah ◽  
Scot T. Martin
Keyword(s):  
Resonant Frequency ◽  
Atomic Force Microscope ◽  
Organic Materials ◽  
Dioctyl Phthalate ◽  
Cloud Formation ◽  
Temperature Dependent ◽  
Temperature Dependent Viscosity ◽  
Atomic Force ◽  
Dependent Viscosity ◽  
Atmospherically Relevant

The viscosity of atmospheric aerosol particles determines the equilibrium timescale at which a molecule diffuses into and out of particles, influencing processes such as gas–particle partitioning, light scattering, and cloud formation that can affect air quality and climate. This particle viscosity is sensitive to environmental conditions such as relative humidity and temperature. Current experimental techniques mainly characterize aerosol viscosity at room temperature. The influence of temperature on the viscosity of organic aerosol remains underexplored. Herein, the viscosity of atmospherically relevant organic materials was examined at a range of temperatures from 15 °C to 95 °C using an atomic force microscope (AFM) equipped with a temperature-controlled sample module. Dioctyl phthalate and sucrose were selected for investigation. Dioctyl phthalate served as the proxy for atmospherically relevant primary organic materials while sucrose served as the proxy for secondary organic materials. The resonant frequency responses of the AFM cantilever within dioctyl phthalate and sucrose were recorded. The link between the resonant frequency and material viscosity was established via a hydrodynamic function. Results obtained from this study were consistent with previously reported viscosities, thus demonstrating the critical capability of AFM in temperature-dependent viscosity measurements.

Self-Adaptable Carbon Fiber Composite

2018 ◽  
Author(s):  
Arnaldo Casalotti ◽  
Krishna C. Chinnam ◽  
Giulia Lanzara
Keyword(s):  
Carbon Fiber ◽  
Smart Materials ◽  
Structural Integrity ◽  
Fiber Composite ◽  
Carbon Fiber Composites ◽  
Smart Composite ◽  
Temperature Dependent ◽  
Carbon Fiber Composite ◽  
Composite Layers ◽  
Actual Material

This article illustrates an approach to develop innovative smart materials based on carbon fiber composites. The proposed approach relies on the use of ultra-light strain sensors that are embedded into the composite and are adopted to monitor in real-time the actual material configuration. Such sensors are composed of electrospun PVDF fibers that exploit piezoelectricity to identify strain and thanks to their extreme lightweight can easily be embedded within the composite layers without affecting the structural integrity. On the other hand, the composite is equipped with a system of internal distributed heaters that can locally and globally vary the composite temperature. Since the adopted epoxy has a considerable temperature-dependent behaviour, it is possible to control its stiffness and thus to control the structural frequencies and damping. By coupling the sensing system with the control system, the structural properties are tuned to match prescribed working conditions, thus optimizing the performance of the proposed smart system. The proposed approach is investigated experimentally by manufacturing prototypes of the smart composite and by performing multiple tests to study the material response and evaluate the obtained performance.

Smart Organic Materials with Acidochromic Properties

2020 ◽  
Vol 24 (17) ◽  
pp. 1976-1998
Author(s):  
Tanisha Sachdeva ◽  
Shalu Gupta ◽  
Marilyn Daisy Milton
Keyword(s):  
Optical Properties ◽  
Diffraction Analysis ◽  
Smart Materials ◽  
Organic Materials ◽  
Color Change ◽  
Theoretical Calculations ◽  
Logic Gates ◽  
Data Encryption ◽  
Fine Tuning ◽  
Molecular Logic Gates

Smart materials displaying changes in color and optical properties in response to acid stimuli are known as acidochromic materials. The recent progress and emerging trends in the field of smart organic materials with acidochromic properties, reported in the last seven years, are presented herein. The molecular design of acidochromic organic materials, the origin of the chromic and fluorochromic response to acid stimuli, and related mechanisms are also discussed. Materials and systems covered in the review are divided according to the presence of basic moiety undergoing reversible protonation/ deprotonation, such as pyridine, quinoline, quinoxaline, azole, amine derivatives, etc., in the molecules. Many donor-acceptor molecules displaying acidochromic behavior are cited. Alterations in visual color change and optical properties supporting acidochromism are discussed for each example. Mechanistic studies based on the theoretical calculations, single crystal X-ray diffraction analysis, and powder pattern diffraction analysis are also discussed here. The application of these acidochromic molecules as acid-base switches, sensor films, self-erasable and rewritable media, data security inks, data encryption, molecular logic gates, etc., are also reported. Thus, this review article aims at giving an insight into the design, characterization, mechanism, and applications of organic acidochromic materials, which will guide the researchers in designing and fine-tuning new acidochromic materials for desired applications.

Temperature-dependent dynamic property of magnetorheological gel composite: experiment and modelling

2021 ◽  
Author(s):  
Runsong Mao ◽  
Guang Zhang ◽  
huixing wang ◽  
Jiong Wang
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Storage Modulus ◽  
Magnetic Field Strength ◽  
Dynamic Property ◽  
Smart Materials ◽  
Effect Of Temperature ◽  
Temperature Dependency ◽  
Temperature Dependent ◽  
Field Strengths

Abstract Of all the smart materials that could vary with the change of external excitations, magnetorheological gel (MRG) is one of the most preeminent composites which appear controllable and reversible responses according to the magnitude of external magnetic field. Temperature is identified as another important driver of the alteration of dynamic property of MRG, which so far has not been studied systematically. The temperature-dependent dynamic property of MRG under different magnetic field strengths are investigated by three kinds of experiments –– strain amplitude, frequency and magnetic field sweep test. The experimental results demonstrate that the storage and loss moduli of MRG display a temperature-induced stiffening effect with a magnetic field, while a temperature-induced softening effect without a magnetic field. Besides, storage modulus improves with magnetic field strength, whereas loss modulus firstly appears a rapid growth and then a gradual reduction with the increment of magnetic field strength. This temperature-dependency of dynamic property is also interpreted through different mechanisms related to the transformation of microstructures of MRG. Furthermore, a modified magnetic dipole model which could predict the relationship between storage modulus and magnetic field strength, combines with the classical Arrhenius equation expressing the effect of temperature on viscosity, to describe the temperature-dependency of storage modulus of MRG under different magnetic field strengths. This paper may provide some useful guidance for designing an MR device.

Application of Improved Voltage Compensation in the SEM to Imaging of Organic Materials

1973 ◽  
Vol 31 ◽  
pp. 444-445
Author(s):  
P.J. Killingworth ◽  
M. Warren
Keyword(s):  
Electron Beam ◽  
Organic Materials ◽  
Operating Parameters ◽  
Low Density ◽  
Beam Diameter ◽  
Incident Electron Beam ◽  
Specimen Material ◽  
Voltage Compensation ◽  
Selection Of ◽  
Scanning Electron

Ultimate resolution in the scanning electron microscope is determined not only by the diameter of the incident electron beam, but by interaction of that beam with the specimen material. Generally, while minimum beam diameter diminishes with increasing voltage, due to the reduced effect of aberration component and magnetic interference, the excited volume within the sample increases with electron energy. Thus, for any given material and imaging signal, there is an optimum volt age to achieve best resolution.In the case of organic materials, which are in general of low density and electric ally non-conducting; and may in addition be susceptible to radiation and heat damage, the selection of correct operating parameters is extremely critical and is achiev ed by interative adjustment.

(111) Monocrystalline Nickel Films

1972 ◽  
Vol 30 ◽  
pp. 512-513
Author(s):  
T.E. Pratt ◽  
R.W. Vook
Keyword(s):  
Film Thickness ◽  
Deposition Rate ◽  
Room Temperature ◽  
Narrow Range ◽  
High Vacuum ◽  
Residual Pressure ◽  
Temperature Dependent ◽  
Deposition Parameters ◽  
Transmission Electron ◽  
Substrate Temperatures

(111) oriented thin monocrystalline Ni films have been prepared by vacuum evaporation and examined by transmission electron microscopy and electron diffraction. In high vacuum, at room temperature, a layer of NaCl was first evaporated onto a freshly air-cleaved muscovite substrate clamped to a copper block with attached heater and thermocouple. Then, at various substrate temperatures, with other parameters held within a narrow range, Ni was evaporated from a tungsten filament. It had been shown previously that similar procedures would yield monocrystalline films of CU, Ag, and Au.For the films examined with respect to temperature dependent effects, typical deposition parameters were: Ni film thickness, 500-800 A; Ni deposition rate, 10 A/sec.; residual pressure, 10-6 torr; NaCl film thickness, 250 A; and NaCl deposition rate, 10 A/sec. Some additional evaporations involved higher deposition rates and lower film thicknesses.Monocrystalline films were obtained with substrate temperatures above 500° C. Below 450° C, the films were polycrystalline with a strong (111) preferred orientation.

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