scholarly journals Synthesis and Adsorbing Properties of Tabular {001} Calcite Crystals

Crystals ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 16 ◽  
Author(s):  
Nives Matijaković ◽  
Giulia Magnabosco ◽  
Francesco Scarpino ◽  
Simona Fermani ◽  
Giuseppe Falini ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
Crystal Violet ◽  
High Power ◽  
Adsorption Properties ◽  
Exposed Surface ◽  
Dye Molecules ◽  
Optimal Conditions ◽  
Almost All ◽  
Adsorption Capability ◽  
Stable Polymorph

One of the most common crystal habits of the thermodynamically stable polymorph of calcium carbonate, calcite, is the rhombohedral one, which exposes {10.4} faces. When calcite is precipitated in the presence of Li+ ions, dominantly {00.1} faces appear together with the {10.4}, thus generating truncated rhombohedrons. This well-known phenomenon is explored in this work, with the aim of obtaining calcite crystals with smooth {00.1} faces. In order to achieve this objective, the formation of calcite was examined in precipitation systems with different c(Ca2+)/c(Li+) ratios and by performing an initial high-power sonication. At the optimal conditions, a precipitate consisting of thin, tabular {001} calcite crystals and very low content of incorporated Li+ has been obtained. The adsorption properties of the tabular crystals, in which the energetically unstable {00.1} faces represent almost all of the exposed surface, were tested with model dye molecules, calcein and crystal violet, and compared to predominantly rhombohedral crystals. It was found that the {00.1} crystals showed a lower adsorption capability when compared to the {10.4} crystals for calcein, while the adsorption of crystal violet was similar for both crystal morphologies. The obtained results open new routes for the usage of calcite as adsorbing substrates and are relevant for the understanding of biomineralization processes in which the {00.1} faces often interact with organic macromolecules.

Quantitative Freeze Fracture Studies of Gap Junctions in Somatic Cell Hybrids, Their Parents, and Revertants

1976 ◽  
Vol 34 ◽  
pp. 218-219
Author(s):  
W. J. Larsen ◽  
R. Azarnia ◽  
W. R. Loewenstein
Keyword(s):  
Gap Junctions ◽  
Striated Muscle ◽  
Freeze Fracture ◽  
Cell Movement ◽  
Dye Molecules ◽  
Somatic Cell Hybrids ◽  
Cell Coupling ◽  
Normal Cells ◽  
Mediate Cell ◽  
Almost All

Although the physiological significance of the gap junction remains unspecified, these membrane specializations are now recognized as common to almost all normal cells (excluding adult striated muscle and some nerve cells) and are found in organisms ranging from the coelenterates to man. Since it appears likely that these structures mediate the cell-to-cell movement of ions and small dye molecules in some electrical tissues, we undertook this study with the objective of determining whether gap junctions in inexcitable tissues also mediate cell-to-cell coupling.To test this hypothesis, a coupling, human Lesh-Nyhan (LN) cell was fused with a non-coupling, mouse cl-1D cell, and the hybrids, revertants, and parental cells were analysed for coupling with respect both to ions and fluorescein and for membrane junctions with the freeze fracture technique.

On-Demand Guest Release from MOF-5 Sealed with Nitrophenylacetic Acid Photocapping Groups

2019 ◽  
Author(s):  
Jingjing Yan ◽  
Rick Homan ◽  
Corrianna Boucher ◽  
Prem N. Basa ◽  
Katherine Fossum ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Crystal Violet ◽  
Dye Molecules ◽  
Phenyl Acetic Acid ◽  
On Demand ◽  
Crystal Violet Dye ◽  
Dye Diffusion ◽  
Triphenylacetic Acid

Recently, we demonstrated that triphenylacetic acid could be used to seal dye molecules within MOF-5, but guest release required digestion of the framework by treatment with acid. We prepared the sterically bulky photocapping group [bis-(3-nitro-benzyl)-amino]-(3-nitro-phenyl)-acetic acid (PC1) can prevent Crystal violet dye diffusion from inside MOF-5 until removed by photolysis.

On-Demand Guest Release from MOF-5 Sealed with Nitrophenylacetic Acid Photocapping Groups

2019 ◽  
Author(s):  
Jingjing Yan ◽  
Rick Homan ◽  
Corrianna Boucher ◽  
Prem N. Basa ◽  
Katherine Fossum ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Crystal Violet ◽  
Dye Molecules ◽  
Phenyl Acetic Acid ◽  
On Demand ◽  
Crystal Violet Dye ◽  
Dye Diffusion ◽  
Triphenylacetic Acid

Recently, we demonstrated that triphenylacetic acid could be used to seal dye molecules within MOF-5, but guest release required digestion of the framework by treatment with acid. We prepared the sterically bulky photocapping group [bis-(3-nitro-benzyl)-amino]-(3-nitro-phenyl)-acetic acid (PC1) can prevent Crystal violet dye diffusion from inside MOF-5 until removed by photolysis.

scholarly journals The surface-enhanced resonance Raman scattering of dye molecules adsorbed on two-dimensional titanium carbide Ti3C2Tx (MXene) film

2020 ◽  
Vol 1 (2) ◽  
pp. 146-152 ◽  
Author(s):  
Satheeshkumar Elumalai ◽  
John R. Lombardi ◽  
Masahiro Yoshimura
Keyword(s):  
Raman Scattering ◽  
Titanium Carbide ◽  
Crystal Violet ◽  
Enhancement Factor ◽  
Resonance Raman ◽  
Raman Signal ◽  
Two Dimensional ◽  
Dye Molecules ◽  
Resonance Raman Scattering ◽  
Surface Enhanced

The resonance Raman signal enhancement of crystal violet dyes onto the two-dimensional MXene–Ti3C2Tx film, so called MXenes-enhanced resonance Raman scattering (MERRS), is reported with a calculated enhancement factor of 3.42 × 109.

The Preparation of the Second Modification of Activated Carbon Fiber Loaded Mn

2011 ◽  
Vol 109 ◽  
pp. 261-265
Author(s):  
Lu Lu ◽  
Jing Zhang ◽  
Ying Chun Yan
Keyword(s):  
Activated Carbon ◽  
Adsorption Properties ◽  
Activated Carbon Fiber ◽  
Impregnation Method ◽  
Optimal Conditions ◽  
Activation Time ◽  
Time Condition ◽  
Orthogonal Experiments ◽  
Iodine Adsorption ◽  
N2 Activation

The Mn loaded ACF (ACF-Mn), prepared by impregnation method combined with activation method under high temperature, can be second modified. The best second modifiers, modifier concentration and activation time condition for ACF-Mn was determine by orthogonal experiments. The modified ACF was characterized by XRD、SEM、EDS and other ways. The results show that the optimal conditions for the second modification was that at 700°C under the protection of N2 activation for 50 min when the modifier concentration of CuSO4 was 10%. The iodine adsorption value of the second modified ACF is 1605.36 mgg-1, and the content of basic functional groups is 119.86 mmolg-1. The granular Cu, Mn attached to the surface of ACF and significantly increased its crystallinity. This is helpful to increase the surface area and enhance its adsorption properties.

scholarly journals A Leukocyte image fast scanning based on max–min distance clustering

2016 ◽  
Vol 09 (06) ◽  
pp. 1650022
Author(s):  
Yapin Wang ◽  
Yiping Cao
Keyword(s):  
Low Power ◽  
High Power ◽  
Blood Smear ◽  
Human Peripheral Blood ◽  
Lower Proportion ◽  
Field Of View ◽  
Clustering Method ◽  
Scanning Method ◽  
Scanning Time ◽  
Almost All

A leukocyte image fast scanning method based on max-min distance clustering is proposed. Because of the lower proportion and uneven distribution of leukocytes in human peripheral blood, there will not be any leukocyte in lager quantity of the captured images if we directly scan the blood smear along an ordinary zigzag scanning routine with high power (100x) objective. Due to the larger field of view of low power (10x) objective, the captured low power blood smear images can be used to locate leukocytes. All of the located positions make up a specific routine, if we scan the blood smear along this routine with high power objective, there will be definitely leukocytes in almost all of the captured images. Considering the number of captured images is still large and some leukocytes may be redundantly captured twice or more, a leukocyte clustering method based on max–min distance clustering is developed to reduce the total number of captured images as well as the number of redundantly captured leukocytes. This method can improve the scanning efficiency obviously. The experimental results show that the proposed method can shorten scanning time from 8.0–14.0[Formula: see text]min to 2.5–4.0[Formula: see text]min while extracting 110 nonredundant individual high power leukocyte images.

scholarly journals Probing the interactions between dye molecules and metallic nanoparticles - Implications for surface enhanced spectroscopies

2021 ◽  
Author(s):  
◽  
Brendan Darby
Keyword(s):  
Silver Nanoparticles ◽  
Shell Model ◽  
Absorption Spectra ◽  
Crystal Violet ◽  
Metallic Nanoparticles ◽  
Integrating Sphere ◽  
Dye Molecules ◽  
Colloidal Solutions ◽  
Excitation Profile ◽  
Surface Enhanced

<p>The work in this thesis focuses on improving the understanding of two key aspects of the interaction between dye molecules and metallic nanoparticles, with particular relevance to Surface Enhanced Raman Spectroscopy (SERS). This is manifested from two main branches of experimental work; the first is concerned with improving the reproducibility of SERS sample preparation using colloidal solutions while the second focuses on directly measuring the absorption spectra of commonly used dye molecules on the surface of colloidal silver nanoparticles.  In the first body of work of the thesis, a major step towards improving SERS in colloidal solutions is achieved by highlighting a crucial, but unnoticed possible source of error for such samples; by comparing average enhancement factor measurements on colloidal solutions prepared using different analyte (dye) dilution methods, it is shown that large dye dilution factors can cause extreme variations in nanoparticle coverage across the entire sample. This not only causes analyte-dependent enhancement factors (which is highly undesirable) but can also lead to false identification of single-molecule SERS experiments using the well established bi-analyte method.  The errors associated with large dilution factors are interpreted as a competition between dye diffusion and adsorption kinetics. Time dependent fluorescence quenching measurements and finite element modelling (FEM) in COMOSL show that in any system where adsorption competes with diffusion, large dilution factors should be avoided. A simple protocol of half-half dilutions of analytes is proposed as a standard method to be adopted when preparing colloidal solutions for SERS to ensure uniform distribution of analytes is achieved.  The second body of work is an experimental investigation of the modification of the energy levels of commonly used dye molecules adsorbed to spherical silver nanoparticles at sub-monolayer concentrations. Through the use of a novel integrating sphere setup, the absorption spectra of Rhodamine 6G, Nile Blue, Rhodamine 700 and Crystal Violet are successfully measured on the surface of silver colloids at ultra-low concentrations where dye-dye interactions are negligible. These results indicate that for most dyes, absorption pectra on the colloid surface are shifted and/or broadened with respect to the free dye in solution. In the most extreme case, a blue shift of almost 90 nm for Crystal Violet suggests a strong chemical interaction with the silver surface.  A Mie theory shell model of dye-coated silver spheres is found to accurately reproduce the measured evolution of absorption spectra as the dye concentration on the colloid surface is increased but overestimates the enhancement in absorption, which is interpreted as a result of the adsorption geometry of dyes on the surface, not captured by the shell model.  Finally, through careful wavelength dependent SERS measurements, the SERS Raman excitation profile of Crystal Violet is measured and shown to be closely linked to the modified absorbance as obtained in the integrating sphere setup. A standard optical transform model for computing the Raman excitation profile from the modified absorbance is applied and gives good agreement with the measured SERS data. These results represent a direct indication of chemical modifications of resonant molecules used in SERS studies.</p>

Features of adsorption processes for wastewater treatment from zinc ions

2021 ◽  
Vol 6 (2) ◽  
pp. 64-68
Author(s):  
Ihor Petrushka ◽  
◽  
Oksana Bratus ◽  
Kateryna Petrushka ◽  
◽  
...  
Keyword(s):  
Sorption Process ◽  
Adsorption Properties ◽  
Zinc Ions ◽  
Optimal Conditions ◽  
Solid Complex ◽  
Monomolecular Layer ◽  
Maximum Sorption Capacity ◽  
Maximum Sorption ◽  
Adsorption Processes ◽  
Langmuir And Freundlich Models

The results of adsorption properties of complex natural sorbents in relation to the neutralization of zinc ions from wastewater are presented. The adsorption isotherm of Zn2+ ions on complex sorbents (clinoptilolite-shungite) (1:1) according to Langmuir and Freundlich models is constructed, the type of adsorption isotherms according to S. Brunauer classification is established. The value of the maximum sorption capacity of Gmax complex sorbents for Zn2+ ions is calculated. The peculiarities of the sorption process of zinc ions with the formation of a monomolecular layer based on the calculated coefficients of the Langmuir and Freundlich were found. The optimal conditions for the dependence of the degree of absorption of Zn2+ ions by complex sorbents on the duration of the sorption process are determined. The ratio "solid (complex sorbent) - liquid" was determined experimentally.

Synthesis and Adsorption Properties of Crosslinked Starch Microspheres (CSM)

2011 ◽  
Vol 418-420 ◽  
pp. 702-705
Author(s):  
Cong Jian Li ◽  
Qin Tie Lin ◽  
Qian Jun Liu ◽  
Han Ping Pan ◽  
Ru Ting Zheng
Keyword(s):  
Graft Copolymerization ◽  
Removal Rate ◽  
Methyl Violet ◽  
Volume Ratio ◽  
Adsorption Properties ◽  
Orthogonal Test ◽  
Cross Linking ◽  
Optimal Conditions ◽  
Single Factor ◽  
The Cross

Starch as the material, MBAA as the cross-linking agent, Tween60 and Span60 as the emulsifier, K2S2O8-Na2SO4 as the initiator, the cyclohexane as the oil phase and the removal rate of methyl violet as an index, crosslinked starch microspheres (CSM) was synthetized by means of reverse suspension emulsion and graft-copolymerization method through orthogonal test and single factor optimization experiment. The results showed the optimal conditions of the preparation of the crosslinked starch microspheres(CSM) were as follow: the concentration of the starch is 5%, the dosage of the MBAA, initiator and emulsifier are 0.125g, 0.5g and 0.6g, the volume ratios between the Span60 and Tween60 is 85:15, and the volume ratio between the cyclohexane and water is 4:1.

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