Study of Cu2O particle morphology on microwave field enhancement

Transmission electron microscopy is an important approach to the characterization of the morphology of multiphase latices. Various sample preparation techniques have been applied to multiphase latices such as OsO4, RuO4 and CsOH stains to distinguish the polymer phases or domains. Radiation damage by an electron beam of latices imbedded in ice has also been used as a technique to study particle morphology. Further studies have been developed in the use of freeze-fracture and the effect of differential radiation damage at liquid nitrogen temperatures of the latex particles embedded in ice and not embedded.Two different series of two-stage latices were prepared with (1) a poly(methyl methacrylate) (PMMA) seed and poly(styrene) (PS) second stage; (2) a PS seed and PMMA second stage. Both series have varying amounts of second-stage monomer which was added to the seed latex semicontinuously. A drop of diluted latex was placed on a 200-mesh Formvar-carbon coated copper grid.

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Surface energy of cellulosic materials: The effect of particle morphology, particle size, and hydroxyl number

TAPPI Journal ◽

10.32964/tj14.9.565 ◽

2015 ◽

Vol 14 (9) ◽

pp. 565-576 ◽

Cited By ~ 1

Author(s):

YUCHENG PENG ◽

DOUGLAS J. GARDNER

Keyword(s):

Particle Size ◽

Surface Energy ◽

Particle Morphology ◽

Nanofibrillated Cellulose ◽

Particle Sizes ◽

Hydroxyl Number ◽

Small Individual ◽

Dispersion Component ◽

Commercial Applications ◽

Lower Temperature

Understanding the surface properties of cellulose materials is important for proper commercial applications. The effect of particle size, particle morphology, and hydroxyl number on the surface energy of three microcrystalline cellulose (MCC) preparations and one nanofibrillated cellulose (NFC) preparation were investigated using inverse gas chromatography at column temperatures ranging from 30ºC to 60ºC. The mean particle sizes for the three MCC samples and the NFC sample were 120.1, 62.3, 13.9, and 9.3 μm. The corresponding dispersion components of surface energy at 30°C were 55.7 ± 0.1, 59.7 ± 1.3, 71.7 ± 1.0, and 57.4 ± 0.3 mJ/m2. MCC samples are agglomerates of small individual cellulose particles. The different particle sizes and morphologies of the three MCC samples resulted in various hydroxyl numbers, which in turn affected their dispersion component of surface energy. Cellulose samples exhibiting a higher hydroxyl number have a higher dispersion component of surface energy. The dispersion component of surface energy of all the cellulose samples decreased linearly with increasing temperature. MCC samples with larger agglomerates had a lower temperature coefficient of dispersion component of surface energy.

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Scanning-tunneling spectroscopy on conjugated polymer films

MRS Proceedings ◽

10.1557/proc-771-l4.3 ◽

2003 ◽

Vol 771 ◽

Author(s):

M. Kemerink ◽

S.F. Alvarado ◽

P.M. Koenraad ◽

R.A.J. Janssen ◽

H.W.M. Salemink ◽

...

Keyword(s):

Polymer Films ◽

Conjugated Polymer ◽

Three Dimensional ◽

Field Enhancement ◽

Direct Consequence ◽

Scanning Tunneling Spectroscopy ◽

Tunneling Spectroscopy ◽

Band Alignment ◽

Scanning Tunneling ◽

Order Of Magnitude

AbstractScanning-tunneling spectroscopy experiments have been performed on conjugated polymer films and have been compared to a three-dimensional numerical model for charge injection and transport. It is found that field enhancement near the tip apex leads to significant changes in the injected current, which can amount to more than an order of magnitude, and can even change the polarity of the dominant charge carrier. As a direct consequence, the single-particle band gap and band alignment of the organic material can be directly obtained from tip height-voltage (z-V) curves, provided that the tip has a sufficiently sharp apex.

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Interference Effects of a Powerful Pulsed Microwave Field on Microphone Devices

Telecommunications and Radio Engineering ◽

10.1615/telecomradeng.v66.i17.80 ◽

2007 ◽

Vol 66 (17) ◽

pp. 1583-1590

Author(s):

A. V. Berdyshev ◽

V. V. Shcherenkov ◽

A. P. Yarygin ◽

Vladimir B. Avdeev

Keyword(s):

Microwave Field ◽

Interference Effects

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Colloidal Plasmonic Nanostar Antennas with Wide Range Resonance Tunability

10.26434/chemrxiv.6552743 ◽

2019 ◽

Cited By ~ 1

Author(s):

Theodoros Tsoulos ◽

Supriya Atta ◽

Maureen Lagos ◽

Michael Beetz ◽

Philip Batson ◽

...

Keyword(s):

Single Particle ◽

Structural Complexity ◽

Field Enhancement ◽

Hot Electron ◽

Structure Property ◽

Plasmon Band ◽

Gold Nanostars ◽

Wide Range ◽

Particle Level ◽

Spectrally Resolved

<div>Gold nanostars display exceptional field enhancement properties and tunable resonant modes that can be leveraged to create effective imaging tags or phototherapeutic agents, or to design novel hot-electron based photocatalysts. From a fundamental standpoint, they represent important tunable platforms to study the dependence of hot carrier energy and dynamics on plasmon band intensity and position. Toward the realization of these platforms, holistic approaches taking into account both theory and experiments to study the fundamental behavior of these</div><div>particles are needed. Arguably, the intrinsic difficulties underlying this goal stem from the inability to rationally design and effectively synthesize nanoparticles that are sufficiently monodispersed to be employed for corroborations of the theoretical results without the need of single particle experiments. Herein, we report on our concerted computational and experimental effort to design, synthesize, and explain the origin and morphology-dependence of the plasmon modes of a novel gold nanostar system, with an approach that builds upon the well-known plasmon hybridization model. We have synthesized monodispersed samples of gold nanostars with finely tunable morphology employing seed-mediated colloidal protocols, and experimentally observed narrow and spectrally resolved harmonics of the primary surface plasmon resonance mode both at the single particle level (via electron energy loss spectroscopy) and in ensemble (by UV-Vis and ATR-FTIR spectroscopies). Computational results on complex anisotropic gold nanostructures are validated experimentally on samples prepared colloidally, underscoring their importance as ideal testbeds for the study of structure-property relationships in colloidal nanostructures of high structural complexity.</div>

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Assemblies of D-peptides for Targeting Cell Nucleolus

10.26434/chemrxiv.8247179.v1 ◽

2019 ◽

Author(s):

Huaimin Wang ◽

Zhaoqianqi Feng ◽

Weiyi Tan ◽

Bing Xu

Keyword(s):

Particle Morphology ◽

Side Chain ◽

Mechanism Study ◽

Structural Analogue ◽

Hydrophobic Residues ◽

Subcellular Organelles ◽

First Case ◽

New Strategy ◽

Peptide Derivative ◽

Peptide Nanoparticles

<p>Selectively targeting cell nucleolus remains a challenge. Here we report the first case that D-peptides form membraneless molecular condensates with RNA for targeting cell nucleolus. A D-peptide derivative, enriched with lysine and hydrophobic residues, self-assembles to form nanoparticles, which enter cells through clathrin dependent endocytosis and mainly accumulate at cell nucleolus. Structural analogue of the D-peptide reveals that particle morphology of the assemblies, which depends on the side chain modification, favors the cellular uptake. Contrasting to those of the D-peptide, the assemblies of the corresponding L-enantiomer largely localize in cell lysosomes. Preliminary mechanism study suggests that the D-peptide nanoparticles interact with RNA to form membraneless condensates in the nucleolus, which further induces DNA damage and results in cell death. This work illustrates a new strategy for rationally designing supramolecular assemblies of D-peptides for targeting subcellular organelles.</p>

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THE ENERGY EFFICIENCY TECHNIQUE OF THERMAL PROCESSING OF GRAIN

Аграрний вісник Причорномор'я ◽

10.37000/abbsl.2019.94.23 ◽

2019 ◽

pp. 176-182

Author(s):

А. Zykov ◽

S. Orlova ◽

L. Ovsiannykova

Keyword(s):

Energy Efficiency ◽

Thermal Processing ◽

Microwave Field ◽

Low Frequency ◽

Heat Pipes ◽

Biologically Active ◽

Microwave Drying ◽

Post Harvest ◽

Combined Action ◽

Frequency Radiation

The methods of energy efficiency increasing of pre- and post-harvest thermal processing of grain are considered. The effective ways to deliver energy to the grain using heat pipes and microwave field are given. The effect of combined action of microwave and low-frequency radiation on the grain germination is shown. Currently, the intensification of technological processes under the influence of microwave radiation is used in many industrial processes. Microwave equipment is becoming a necessary technological component of large profitable industries. The process of drying is no exception. In recent years, new versions of dryers have been proposed that use combined methods of energy supply, including microwave energy. Microwave dryers for foodstuffs, grains and oilseeds, including those for seed stock, have been created and are beginning to be used, along with drying and disinfection, disinfection of drying products from harmful bacteria, fungi, and mildew. For the implementation of microwave drying of particular importance is the choice of regime parameters of drying, given the fact that the grain is a biologically active object. Microwave drying allows you to provide a powerful flow of energy to the object of drying and to obtain a significant intensification of moisture evaporation. But at the same time there is also an intense heating of the product, which can degrade its quality. The possibility of supplying energy throughout the cross section of the product allows for the evaporation of moisture from the inner layers of the product, which is especially important at the end of drying, when the zone of evaporation of moisture is significantly deeper. Therefore, the highest drying efficiency can be obtained in combined processes that take advantage of various drying methods, such as convective, as well as the use of microwave and low-frequency magnetic fields. The paper presents effective ways to supply energy to the grain using heat pipes and a microwave field. The effect of the combined action of microwave and low-frequency radiation on grain similarity is shown. Ways to improve the energy efficiency of the processes of preseeding and post-harvest heat treatment of grain are considered.

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Oxidation decomposition of toluene waste gas by catalyst in microwave field

JOURNAL OF SHENZHEN UNIVERSITY SCIENCE AND ENGINEERING ◽

10.3724/sp.j.1249.2018.06582 ◽

2018 ◽

Vol 35 (6) ◽

pp. 582 ◽

Cited By ~ 1

Author(s):

Ning WANG ◽

Bin GUO ◽

Xin WANG ◽

Xurui HU ◽

Ailing REN ◽

...

Keyword(s):

Microwave Field ◽

Waste Gas

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Controlled Growth and Characterization Ag/ZnO Nanotetrapods for Humidity Sensing

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207321666180717120417 ◽

2018 ◽

Vol 21 (7) ◽

pp. 462-467

Author(s):

Babak Sadeghi

Keyword(s):

Room Temperature ◽

Zinc Complex ◽

Water Solution ◽

Particle Morphology ◽

Quick Response ◽

Separation System ◽

Humidity Sensing ◽

Sensor Material ◽

Highly Sensitive

Aim and Objective: Ultrafine Ag/ZnO nanotetrapods (AZNTP) have been prepared successfully using silver (I)–bis (oxalato) zinc complex and 1, 3-diaminopropane (DAP) with a phase separation system, and have been injected into a diethyl/water solution. Materials and Methods: This crystal structure and lattice constant of the AZNTP obtained were investigated by means of a SEM, XRD, TEM and UV-vis spectrum. Results: The results of the present study demonstrated the growth and characterization AZNTP for humidity sensing and DAP plays a key role in the determination of particle morphology. AZNTP films with 23 nm in arm diameter have shown highly sensitive, quick response sensor material that works at room temperature.

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