Crystal structures, CO2 adsorption, and dielectric properties of [Cu(ii)2(R-benzoate)4(pyrazine)]∞ polymers (R = m-F, 2,3-F2, m-Cl, and m-CH3)

2014 ◽  
Vol 43 (24) ◽  
pp. 9081-9089 ◽  
Author(s):  
Kiyonori Takahashi ◽  
Norihisa Hoshino ◽  
Takashi Takeda ◽  
Shin-ichiro Noro ◽  
Takayoshi Nakamura ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Crystal Structures ◽  
Gas Adsorption ◽  
Co2 Adsorption ◽  
Interchain Interactions ◽  
Adsorption Desorption ◽  
The Relationship

The relationship between the interchain interactions and CO2 gas adsorption–desorption properties, and dielectric responses under CO2 desorbed conditions.

Microwave characteristics of BaPr2Ti4O12 and BaPr2Ti5O14 ceramics

1995 ◽  
Vol 10 (2) ◽  
pp. 312-319 ◽  
Author(s):  
Koichi Fukuda ◽  
Ryozo Kitoh ◽  
Ikuo Awai
Keyword(s):  
Solid Solution ◽  
Dielectric Properties ◽  
Crystal Structures ◽  
Microwave Dielectric Properties ◽  
Far Infrared ◽  
Reflection Spectra ◽  
Microwave Dielectric ◽  
Infrared Reflection ◽  
The Relationship ◽  
Microwave Characteristics

Microwave dielectric properties and microstructures of BaPr2Ti4O12 and BaPr2Ti5O14 ceramics which have extremely similar crystal structures, were investigated, including those of the solid solution represented by the formula of Ba6−xPr8+2x/3Ti18O54 ceramics. It is suggested that BaPr2Ti5O14 ceramics are composed of mixed phases, approximately 85.0 vol. % Ba4.05Pr9.3Ti18O54 (x = 1.95), 8.1 vol. % TiO2, and 6.9 vol. % BaTi4O9. The microwave dielectric properties of the Ba6−xPr8+2x/3Ti18O54 system are strongly dependent on the x value, which is interesting for studying the relationship between microstructures and dielectric properties. Far infrared reflection spectra were also measured to study the mixed phases formed in these ceramics in more detail.

scholarly journals Experimental Study of the Characteristic Changes of Coal Resistivity during the Gas Adsorption/Desorption Process

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Zengchao Feng ◽  
Chen Wang ◽  
Dong Dong ◽  
Dong Zhao ◽  
Dong Zhou
Keyword(s):  
Gas Adsorption ◽  
Gas Content ◽  
Resistivity Change ◽  
Adsorption Experiment ◽  
Desorption Process ◽  
Continuous Adsorption ◽  
Gas Desorption ◽  
Original Figure ◽  
Adsorption Desorption ◽  
The Relationship

To study the influence of gas adsorption-desorption on the resistivity of coal, the resistivity changes in conditions of continuous adsorption/desorption and isovolumetric adsorption/desorption were tested by high-precision resistance measurement, and the relationship between coal resistivity and gas content was investigated. The results show that gas adsorption/desorption has obvious effects on the resistivity of coal. Similar behavior was observed both in continuous adsorption/desorption and in isovolumetric adsorption/desorption experiments. The coal resistivity decreased gradually at the very beginning and then tended to stabilize as the gas adsorption capacity increased; in the process of gas desorption, the resistivity demonstrated a linear relationship with gas content. When comparing resistivities for the different adsorption modes, it was found that, for the same gas content in each mode, the resistivity change in the isovolumetric adsorption experiment was more obvious than in the continuous adsorption experiment. Also, the coal resistivity in the isovolumetric experiment differed further from the original figure when the desorption ended. The results are significant for predicting gas content in the coal mining process.

Soil and Stream Water Chemistry During Spring Snowmelt

1992 ◽  
Vol 23 (1) ◽  
pp. 13-26 ◽  
Author(s):  
W. H. Hendershot ◽  
L. Mendes ◽  
H. Lalande ◽  
F. Courchesne ◽  
S. Savoie
Keyword(s):  
Stream Water ◽  
Base Cations ◽  
Stream Chemistry ◽  
Stream Water Chemistry ◽  
The Matrix ◽  
Adsorption Desorption ◽  
The Relationship ◽  
Best Fit ◽  
Spring Snowmelt ◽  
Over Time

In order to determine how water flowpath controls stream chemistry, we studied both soil and stream water during spring snowmelt, 1985. Soil solution concentrations of base cations were relatively constant over time indicating that cation exchange was controlling cation concentrations. Similarly SO4 adsorption-desorption or precipitation-dissolution reactions with the matrix were controlling its concentrations. On the other hand, NO3 appeared to be controlled by uptake by plants or microorganisms or by denitrification since their concentrations in the soil fell abruptly as snowmelt proceeded. Dissolved Al and pH varied vertically in the soil profile and their pattern in the stream indicated clearly the importance of water flowpath on stream chemistry. Although Al increased as pH decreased, the relationship does not appear to be controlled by gibbsite. The best fit of calculated dissolved inorganic Al was obtained using AlOHSO4 with a solubility less than that of pure crystalline jurbanite.

scholarly journals Self-Assembly of Shape-Tunable Oblate Colloidal Particles into Orientationally Ordered Crystals, Glassy Crystals and Plastic Crystals

Soft Matter ◽  
2021 ◽  
Author(s):  
Jiawei Lu ◽  
Xiangyu Bu ◽  
Xinghua Zhang ◽  
Bing Liu
Keyword(s):  
Crystal Structures ◽  
Self Assembly ◽  
Colloidal Particles ◽  
Building Blocks ◽  
Fundamental Question ◽  
The Self ◽  
Plastic Crystals ◽  
Self Assembled ◽  
Glassy Crystals ◽  
The Relationship

The shapes of colloidal particles are crucial to the self-assembled superstructures. Understanding the relationship between the shapes of building blocks and the resulting crystal structures is an important fundamental question....

scholarly journals Gas Porosimetry by Gas Adsorption as an Efficient Tool for the Assessment of the Shaping Effect in Commercial Zeolites

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1205
Author(s):  
Alejandro Orsikowsky-Sanchez ◽  
Christine Franke ◽  
Alexander Sachse ◽  
Eric Ferrage ◽  
Sabine Petit ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
Strong Interaction ◽  
Gas Adsorption ◽  
Co2 Adsorption ◽  
Adsorption Properties ◽  
Preparation Process ◽  
Pore Filling ◽  
Irreversible Adsorption ◽  
Efficient Tool ◽  
4A Zeolite

A set of three commercial zeolites (13X, 5A, and 4A) of two distinct shapes have been characterized: (i) pure zeolite powders and (ii) extruded spherical beads composed of pure zeolite powders and an unknown amount of binder used during their preparation process. The coupling of gas porosimetry experiments using argon at 87 K and CO2 at 273 K allowed determining both the amount of the binder and its effect on adsorption properties. It was evidenced that the beads contain approximately 25 wt% of binder. Moreover, from CO2 adsorption experiments at 273 K, it could be inferred that the binder present in both 13X and 5A zeolites does not interact with the probe molecule. However, for the 4A zeolite, pore filling pressures were shifted and strong interaction with CO2 was observed leading to irreversible adsorption of the probe. These results have been compared to XRD, IR spectroscopy, and ICP-AES analysis. The effect of the binder in shaped zeolite bodies can thus have a crucial impact on applications in adsorption and catalysis.

scholarly journals Influence of the Presence of Different Alkali Cations and the Amount of Fe(CN)6 Vacancies on CO2 Adsorption on Copper Hexacyanoferrates

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3371 ◽  
Author(s):  
Svensson ◽  
Grins ◽  
Eklöf ◽  
Eriksson ◽  
Wardecki ◽  
...  
Keyword(s):  
Thermogravimetric Analysis ◽  
Prussian Blue ◽  
Co2 Adsorption ◽  
X Ray Diffraction ◽  
Alkali Cations ◽  
Prussian Blue Analogue ◽  
X Ray ◽  
Infra Red ◽  
Adsorption Desorption ◽  
Adsorption Capability

The CO2 adsorption on various Prussian blue analogue hexacyanoferrates was evaluated by thermogravimetric analysis. Compositions of prepared phases were verified by energy-dispersive X-ray spectroscopy, infra-red spectroscopy and powder X-ray diffraction. The influence of different alkali cations in the cubic Fm3m structures was investigated for nominal compositions A2/3Cu[Fe(CN)6]2/3 with A = vacant, Li, Na, K, Rb, Cs. The Rb and Cs compounds show the highest CO2 adsorption per unit cell, 3.3 molecules of CO2 at 20 C and 1 bar, while in terms of mmol/g the Na compound exhibits the highest adsorption capability, 3.8 mmol/g at 20 C and 1 bar. The fastest adsorption/desorption is exhibited by the A-cation free compound and the Li compound. The influence of the amount of Fe(CN)6 vacancies were assessed by determining the CO2 adsorption capabilities of Cu[Fe(CN)6]1/2 (Fm3m symmetry, nominally 50% vacancies), KCu[Fe(CN)6]3/4 (Fm3m symmetry, nominally 25% vacancies), and CsCu[Fe(CN)6] (I-4m2 symmetry, nominally 0% vacancies). Higher adsorption was, as expected, shown on compounds with higher vacancy concentrations.

scholarly journals Laser THz Emission Spectroscopy of Gas Adsorption-Desorption Dynamics in Tungsten Disulfide Nanosheets

2016 ◽  
Vol 14 (0) ◽  
pp. 78-82 ◽  
Author(s):  
Filchito Renee Bagsican ◽  
Iwao Kawayama ◽  
Hironaru Murakami ◽  
Masayoshi Tonouchi ◽  
Andrew Winchester ◽  
...  
Keyword(s):  
Emission Spectroscopy ◽  
Gas Adsorption ◽  
Tungsten Disulfide ◽  
Adsorption Desorption

scholarly journals Recycled Mortars with Ceramic Aggregates. Pore Network Transmutation and Its Relationship with Physical and Mechanical Properties

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1543
Author(s):  
Francisca Guadalupe Cabrera-Covarrubias ◽  
José Manuel Gómez-Soberón ◽  
Carlos Antonio Rosas-Casarez ◽  
Jorge Luis Almaral-Sánchez ◽  
Jesús Manuel Bernal-Camacho
Keyword(s):  
Mechanical Properties ◽  
Image Analysis ◽  
Open Porosity ◽  
Gas Adsorption ◽  
Physical And Mechanical Properties ◽  
Recycled Aggregate ◽  
Bet Surface Area ◽  
Sem Image ◽  
The Relationship ◽  
Sem Image Analysis

The porosity of mortars with recycled ceramic aggregates (10, 20, 30, 50, and 100% as a replacement of natural aggregate) was evaluated and analyzed using three different techniques. The results of gas adsorption (N2), Scanning Electron Microscopy (SEM) image analysis and open porosity allowed establishing the relationship between the recycled aggregate content and the porosity of these mortars, as well as the relationship between porosity and the physical and mechanical properties of the mortars: absorption, density, compressive strength, modulus of elasticity, and drying shrinkage. Using the R2 coefficient and the equation typology as criteria, additional data such as Brunauer, Emmett, and Teller (BET) surface area (N2 adsorption) established significant correlations with the mentioned properties; with SEM image analysis, no explanatory relationships could be established; and with open porosity, revealing relationships were established (R2 > 0.9). With the three techniques, it was confirmed that the increase in porosity is related to the increase in the amount of ceramic aggregate; in particular with gas adsorption (N2) and open porosity. It was concluded that the open porosity technique can explain the behavior of these recycled mortars with more reliable data, in a simple and direct way, linked to its establishment with a more representative sample of the mortar matrix.

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