The electrical self-potential method is a non-intrusive snow-hydrological sensor

The functionalization of graphene has been reported widely, showing special physical and chemical properties. However, due to the lack of surface functional groups, the poor dispersibility of graphene in solvents strongly limits its engineering applications. This paper develops a novel green “in-situ titania intercalation” method to prepare a highly dispersed graphene, which is enabled by the generation of the titania precursor between the layer of graphene at room temperature to yield titania-graphene nanocomposites (TiO2-RGO). The precursor of titania will produce amounts of nano titania between the graphene interlayers, which can effectively resist the interfacial van der Waals force of the interlamination in graphene for improved dispersion state. Such highly dispersed TiO2-RGO nanocomposites were used to modify epoxy resin. Surprisingly, significant enhancement of the mechanical performance of epoxy resin was observed when incorporating the titania-graphene nanocomposites, especially the improvements in tensile strength and elongation at break, with 75.54% and 176.61% increases at optimal usage compared to the pure epoxy, respectively. The approach presented herein is easy and economical for industry production, which can be potentially applied to the research of high mechanical property graphene/epoxy composite system.

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The Application of 57FE Mössbauer Spectroscopy to the Characterization of Nuclear Waste Forms

MRS Proceedings ◽

10.1557/proc-6-59 ◽

1981 ◽

Vol 6 ◽

Author(s):

Paul G. Huray ◽

M. T. Spaar ◽

S. E. Nave ◽

J. M. Legan ◽

L. A. Boatner ◽

...

Keyword(s):

Nuclear Waste ◽

Chemical Properties ◽

Electronic Charge ◽

Chemical Information ◽

Waste Forms ◽

Charge States ◽

Physical And Chemical ◽

Nuclear Waste Forms

The electronic charge states and site symmetries of the radioactive ions incorporated in nuclear waste forms are of considerable importance in determining the physical and chemical properties of these materials. An in situ characterization of these ions is, unfortunately, often difficult – especially when a mixture of charge states and local crystal symmetries exist. The application of Mbssbauer spectroscopy represents a powerful technique for obtaining solid state chemical information.

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Electrodeposition of the Ni-Mo+MoO2 Composite Electrocoatings

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.228.132 ◽

2015 ◽

Vol 228 ◽

pp. 132-137 ◽

Cited By ~ 1

Author(s):

B. Łosiewicz ◽

Grzegorz Dercz ◽

Magdalena Popczyk

Keyword(s):

Composite Coating ◽

Steel Substrate ◽

Composite Coatings ◽

Chemical Properties ◽

Alloy Coating ◽

Composite Component ◽

Powder Particles ◽

Physical And Chemical ◽

And Chemical Properties

The Ni-Mo+MoO2composite coatings were obtained onto the steel substrate using anin situco-deposition of a Ni-Mo alloy and MoO2powder particles maintained in suspension in the potassium pyrophosphate bath. To characterize the physical and chemical properties of the obtained coatings, SEM, EDS, and XRD methods, were applied. It was found that the co-deposited MoO2particles strongly influenced the properties of the Ni-Mo alloy coating. In comparison with the comparable Ni-Mo deposit containing 45 at.% of Mo, the presence of MoO2embedded into the composite coating diminished the content of Mo alloyed with Ni to 23 at.%. The electrodeposited Ni-Mo+MoO2composite coating obtained under proposed electrochemical conditions contained 25 at.% of MoO2. The effect of the embedded MoO2as composite component on changes of the surface morphology and structure of the Ni-Mo binary alloy, was also discussed.

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From nanoscopic to macroscopic photo-driven motion in azobenzene-containing materials

Nanophotonics ◽

10.1515/nanoph-2018-0040 ◽

2018 ◽

Vol 7 (8) ◽

pp. 1387-1422 ◽

Cited By ~ 41

Author(s):

Stefano L. Oscurato ◽

Marcella Salvatore ◽

Pasqualino Maddalena ◽

Antonio Ambrosio

Keyword(s):

Liquid Crystalline ◽

Large Scale ◽

Surface Engineering ◽

Spatial Scales ◽

Chemical Properties ◽

Glassy Materials ◽

Uv Visible ◽

Physical And Chemical ◽

And Robotics ◽

And Chemical Properties

AbstractThe illumination of azobenzene molecules with UV/visible light efficiently converts the molecules between trans and cis isomerization states. Isomerization is accompanied by a large photo-induced molecular motion, which is able to significantly affect the physical and chemical properties of the materials in which they are incorporated. In some material systems, the nanoscopic structural movement of the isomerizing azobenzene molecules can be even propagated at macroscopic spatial scales. Reversible large-scale superficial photo-patterning and mechanical photo-actuation are efficiently achieved in azobenzene-containing glassy materials and liquid crystalline elastomers, respectively. This review covers several aspects related to the phenomenology and the applications of the light-driven macroscopic effects observed in these two classes of azomaterials, highlighting many of the possibilities they offer in different fields of science, like photonics, biology, surface engineering and robotics.

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In-situ Detection Method for Microplastics in Water by Polarized Light Scattering

Frontiers in Marine Science ◽

10.3389/fmars.2021.739683 ◽

2021 ◽

Vol 8 ◽

Author(s):

Tong Liu ◽

Shijun Yu ◽

Xiaoshan Zhu ◽

Ran Liao ◽

Zepeng Zhuo ◽

...

Keyword(s):

Light Scattering ◽

Scattered Light ◽

Polarized Light ◽

Chemical Properties ◽

Future Application ◽

Physical And Chemical Properties ◽

The Individual ◽

Physical And Chemical ◽

And Chemical Properties

Microplastics (MPs) have become the widespread contaminants, which raises concerns on their ecological hazards. In-situ detection of MP in water bodies is essential for clear assessment of the ecological risks of MPs. The present study proposes a method based on polarized light scattering which measures the polarization parameters of the scattered light at 120° to detect MP in water. This method takes the advantage of in-situ measurement of the individual particles and the experimental setup in principle is used. By use of the measured polarization parameters equipped by machine learning, the standard polystyrene (PS) spheres, natural water sample, and lab-cultured microalgae are explicitly discriminated, and MP with different physical and chemical properties can be differentiated. It can also characterize the weathering of different MP and identify the specific type from multiple types of MP. This study explores the capability of the proposed method to detect the physical and chemical properties, weathering state and concentration of MP in water which promises the future application in water quality sensing and monitoring.

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What Was Released? Assessing the Physical Properties and Chemical Composition of Petroleum and Products of Burned Oil

Oceanography ◽

10.5670/oceanog.2021.116 ◽

2021 ◽

Vol 34 (1) ◽

pp. 44-57

Author(s):

Jürgen Rullkötter ◽

John Farrington

Keyword(s):

Oil Spills ◽

Complex Mixture ◽

Chemical Properties ◽

Analytical Techniques ◽

Ion Cyclotron Resonance ◽

Model Calculations ◽

Research Questions ◽

Physical And Chemical ◽

And Chemical Properties

The severity of oil spills depends on the quantity of material released and its physical and chemical properties. The total amount of petroleum spilled during the Deepwater Horizon incident and the relative fractions of the chemical compound classes of the Macondo oil were obtained by measurements, observations, and model calculations, with a significant amount of uncertainty. Because petroleum is an extremely complex mixture of many thousands or more of gaseous, liquid, and solid constituents, full elucidation of their compositions at the molecular level is impossible with presently available analytical techniques. This paper reviews published work on widely used analytical techniques and points out that scientists’ varying approaches to research questions and preferences for methods of analysis constitute a source of uncertainty. In addition, the focus is on two technical advancements developed over the last two decades, namely two-dimensional gas chromatography and Fourier transform ion cyclotron resonance mass spectrometry. Both were particularly valuable in the analysis of the spilled Macondo oil and its weathering products. Among the different processes of alteration of the original oil, only in situ oil burning is dealt with in this paper. This review reveals the paucity of data on this mitigation process and shows the need for more systematic coordination of methods in burned oil research studies.

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IR Features of Hydrous Mg2SiO4-Ringwoodite, Unannealed and Annealed at 200–600 °C and 1 atm, with Implications to Hydrogen Defects and Water-Coupled Cation Disorder

Minerals ◽

10.3390/min10060499 ◽

2020 ◽

Vol 10 (6) ◽

pp. 499 ◽

Cited By ~ 2

Author(s):

Xi Liu ◽

Zhaoyang Sui ◽

Hongzhan Fei ◽

Wei Yan ◽

Yunlu Ma ◽

...

Keyword(s):

Chemical Properties ◽

Thermal Expansivity ◽

Absorption Enhancement ◽

Physical And Chemical Properties ◽

Thin Sections ◽

Cation Disorder ◽

Hydrogen Defects ◽

Physical And Chemical ◽

Water Contents ◽

And Chemical Properties

Three batches of Mg2SiO4-ringwoodites (Mg-Rw) with different water contents (CH2O = ~1019(238), 5500(229) and 16,307(1219) ppm) were synthesized by using conventional high-P experimental techniques. Thirteen thin sections with different thicknesses (~14–113 μm) were prepared from them and examined for water-related IR peaks using unpolarized infrared spectra at ambient P-T conditions, leading to the observation of 15 IR peaks at ~3682, 3407, 3348, 3278, 3100, 2849, 2660, 2556, 2448, 1352, 1347, 1307, 1282, 1194 and 1186 cm−1. These IR peaks suggest multiple types of hydrogen defects in hydrous Mg-Rw. We have attributed the IR peaks at ~3680, 3650–3000 and 3000–2000 cm−1, respectively, to the hydrogen defects [VSi(OH)4], [VMg(OH)2MgSiSiMg] and [VMg(OH)2]. Combining these IR features with the chemical characteristics of hydrous Rw, we have revealed that the hydrogen defects [VMg(OH)2MgSiSiMg] are dominant in hydrous Rw at high P-T conditions, and the defects [VSi(OH)4] and [VMg(OH)2] play negligible roles. Extensive IR measurements were performed on seven thin sections annealed for several times at T of 200–600 °C and quickly quenched to room T. They display many significant variations, including an absorption enhancement of the peak at ~3680 cm−1, two new peaks occurring at ~3510 and 3461 cm−1, remarkable intensifications of the peaks at ~3405 and 3345 cm−1 and significant absorption reductions of the peaks at ~2500 cm−1. These phenomena imply significant hydrogen migration among different crystallographic sites and rearrangement of the O-H dipoles in hydrous Mg-Rw at high T. From the IR spectra obtained for hydrous Rw both unannealed and annealed at high T, we further infer that substantial amounts of cation disorder should be present in hydrous Rw at the P-T conditions of the mantle transition zone, as required by the formation of the hydrogen defects [VMg(OH)2MgSiSiMg]. The Mg-Si disorder may have very large effects on the physical and chemical properties of Rw, as exampled by its disproportional effects on the unit-cell volume and thermal expansivity.

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A soil toposequence on bunya phyllite in Brisbane

Soil Research ◽

10.1071/sr9810001 ◽

1981 ◽

Vol 19 (1) ◽

pp. 1

Author(s):

AJ Koppi

Keyword(s):

Chemical Properties ◽

Parent Material ◽

Physical And Chemical Properties ◽

Genetic Unit ◽

Dioctahedral Mica ◽

Physical And Chemical ◽

In Situ Weathering ◽

And Chemical Properties

A common toposequence on Bunya Phyllite in south-east Queensland was studied in detail at a representative site. Four sample profiles on the slope are described, and some physical and chemical properties are given. The clay minerals, derived from the weathering of the quartz-sericite-chlorite phyllite, comprise dioctahedral mica, dioctahedral vermiculite, an interstratification of these minerals, and kaolin. Properties are related to the slope; and the clay-rich horizon of the middle and lower slopes is considered to be formed mostly by in situ weathering. The classification of the genetic unit given by the slope and parent material is discussed.

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Bulk meltwater flow and liquid water content of snowpacks mapped using the electrical self-potential (SP) method

The Cryosphere ◽

10.5194/tc-10-433-2016 ◽

2016 ◽

Vol 10 (1) ◽

pp. 433-444 ◽

Cited By ~ 2

Author(s):

Sarah S. Thompson ◽

Bernd Kulessa ◽

Richard L. H. Essery ◽

Martin P. Lüthi

Keyword(s):

Electrical Conductivity ◽

Water Content ◽

Liquid Water ◽

Low Cost ◽

Sensor Arrays ◽

Ground Truth ◽

Liquid Water Content ◽

Potential Method ◽

Avalanche Forecasting ◽

Self Potential

Abstract. Our ability to measure, quantify and assimilate hydrological properties and processes of snow in operational models is disproportionally poor compared to the significance of seasonal snowmelt as a global water resource and major risk factor in flood and avalanche forecasting. We show here that strong electrical self-potential fields are generated in melting in situ snowpacks at Rhone Glacier and Jungfraujoch Glacier, Switzerland. In agreement with theory, the diurnal evolution of self-potential magnitudes ( ∼  60–250 mV) relates to those of bulk meltwater fluxes (0–1.2  ×  10−6 m3 s−1) principally through the permeability and the content, electrical conductivity and pH of liquid water. Previous work revealed that when fresh snow melts, ions are eluted in sequence and electrical conductivity, pH and self-potential data change diagnostically. Our snowpacks had experienced earlier stages of melt, and complementary snow pit measurements revealed that electrical conductivity ( ∼  1–5  ×  10−6 S m−1) and pH ( ∼  6.5–6.7) as well as permeabilities (respectively ∼  9.7  ×  10−5 and ∼  4.3  ×  10−5 m2 at Rhone Glacier and Jungfraujoch Glacier) were invariant. This implies, first, that preferential elution of ions was complete and, second, that our self-potential measurements reflect daily changes in liquid water contents. These were calculated to increase within the pendular regime from ∼  1 to 5 and ∼  3 to 5.5 % respectively at Rhone Glacier and Jungfraujoch Glacier, as confirmed by ground truth measurements. We conclude that the electrical self-potential method is a promising snow and firn hydrology sensor owing to its suitability for (1) sensing lateral and vertical liquid water flows directly and minimally invasively, (2) complementing established observational programs through multidimensional spatial mapping of meltwater fluxes or liquid water content and (3) monitoring autonomously at a low cost. Future work should focus on the development of self-potential sensor arrays compatible with existing weather and snow monitoring technology and observational programs, and the integration of self-potential data into analytical frameworks.

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Temperature reversible synergistic formation of cerium oxyhydride and Au hydride: a combined XAS and XPDF study

Physical Chemistry Chemical Physics ◽

10.1039/d0cp00455c ◽

2020 ◽

Vol 22 (34) ◽

pp. 18882-18890

Author(s):

Adam H. Clark ◽

Nadia Acerbi ◽

Philip A. Chater ◽

Shusaku Hayama ◽

Paul Collier ◽

...

Keyword(s):

Fluorescence Detection ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Au Catalyst ◽

Total Scattering ◽

X Ray ◽

Physical And Chemical ◽

X Ray Absorption ◽

And Chemical Properties

In situ studies on the physical and chemical properties of the interaction with hydrogen with a ceria coated alumina supported Au catalyst using fluorescence detection X-ray absorption near edge spectroscopy and X-ray total scattering.

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