An aromatic-rich cage-based MOF with inorganic chloride ions decorating the pore surface displaying the preferential adsorption of C2H2 and C2H6 over C2H4

2021 ◽  
Author(s):  
Zhenzhen Jiang ◽  
Lihui Fan ◽  
Ping Zhou ◽  
Tingting Xu ◽  
Simin Hu ◽  
...  
Keyword(s):  
Chloride Ions ◽  
Pore Surface ◽  
Separation And Purification ◽  
Preferential Adsorption ◽  
Inorganic Chloride

An aromatic-rich chloride-embedded nanocage-based MOF displayed an unusual adsorption relationship towards C2 hydrocarbons, with the potential for C2H4 separation and purification application.

A hydrostable cage-based MOF with open metal sites and Lewis basic sites immobilized in the pore surface for efficient separation and purification of natural gas and C2H2

2020 ◽  
Vol 49 (11) ◽  
pp. 3553-3561 ◽  
Author(s):  
Zhenzhen Jiang ◽  
Ying Zou ◽  
Tingting Xu ◽  
Lihui Fan ◽  
Ping Zhou ◽  
...  
Keyword(s):  
Natural Gas ◽  
Gas Separation ◽  
Hydrolytic Stability ◽  
Pore Surface ◽  
Separation And Purification ◽  
Basic Sites ◽  
Efficient Separation ◽  
Open Metal Sites

A cage-based MOF displays excellent hydrolytic stability as well as promising potential for diverse gas separation applications.

First-Principles Study on the Corrosion Mechanism of Degradable Medical Mg Alloys in the Medium Containing Cl-

2014 ◽  
Vol 528 ◽  
pp. 132-137
Author(s):  
Guo Ying Zhang ◽  
Zhi Cheng Luo ◽  
Jie Tang ◽  
Ye Shu Liu ◽  
Chun Ming Liu
Keyword(s):  
First Principles ◽  
Density Functional ◽  
Surface Passivation ◽  
Chloride Ions ◽  
Mg Alloys ◽  
Mg Alloy ◽  
Alloy Surface ◽  
Corrosion Mechanism ◽  
Preferential Adsorption ◽  
High Concentrations

A first-principles plane-wave pseudopotential method based on Density Functional Theory (DFT) has been used to perform a comparative theoretical study of the adsorption H2O and Cl- on a degradable medical Mg alloy (0001) surface. It is found that H2O molecules bind preferentially at atop sites with a large tilt angle away from the surface normal, Cl- ions are energetically favoured adsorbed on hcp hollow sites. In the aqueous solution containing Cl-, the preferential adsorption of Cl- over H2O on Mg surface prevents the Mg surface passivation and induces the corrosion of degradable medical Mg alloys. For H2O adsorption, the ineraction between H2O molecule and Mg surface makes Mg hydration, and thereby Mg alloy surface passivates and the formation of the protective Mg(OH)2. For Cl- ion adsorption, a 0.44e charge translation from Cl- ion to the Mg alloy surface makes the corrosion potential of Mg alloy surface negativly shifted. Thereby, the activity and the corrosion of magnesium alloy are enhanced. This can explain why degradable medical magnesium alloys corrode quickly in physiological media containing high concentrations of chloride ions.

Junction of the Epithelium and Lamina Propria of the Bovine Rumen Mucosa

1967 ◽  
Vol 25 ◽  
pp. 68-69
Author(s):  
Al W. Stinson
Keyword(s):  
Osmium Tetroxide ◽  
Squamous Epithelium ◽  
Short Chain Fatty Acids ◽  
Chloride Ions ◽  
Fermentation Products ◽  
Ruminant Species ◽  
Protective Shield ◽  
Stratified Squamous Epithelium ◽  
Lead Hydroxide ◽  
Acetic Acids

The stratified squamous epithelium which lines the ruminal compartment of the bovine stomach performs at least three important functions. (1) The upper keratinized layer forms a protective shield against the rough, fibrous, constantly moving ingesta. (2) It is an organ of absorption since a number of substances are absorbed directly through the epithelium. These include short chain fatty acids, potassium, sodium and chloride ions, water, and many others. (3) The cells of the deeper layers metabolize butyric acid and to a lesser extent propionic and acetic acids which are the fermentation products of rumen digestion. Because of the functional characteristics, this epithelium is important in the digestive process of ruminant species which convert large quantities of rough, fibrous feed into energy.Tissue used in this study was obtained by biopsy through a rumen fistula from clinically healthy, yearling holstein steers. The animals had been fed a typical diet of hay and grain and the ruminal papillae were fully developed. The tissue was immediately immersed in 1% osmium tetroxide buffered to a pH of 7.4 and fixed for 2 hrs. The tissue blocks were embedded in Vestapol-W, sectioned with a Porter-Blum microtome with glass knives and stained with lead hydroxide. The sections were studied with an RCA EMU 3F electron microscope.

Factors Influencing the Separation of Glu-Plasminogen Affinity Forms I and II by Affinity Chromatography

1984 ◽  
Vol 52 (03) ◽  
pp. 347-349 ◽  
Author(s):  
Daan W Traas ◽  
Bep Hoegee-de Nobel ◽  
Willem Nieuwenhuizen
Keyword(s):  
Affinity Chromatography ◽  
Dissociation Constants ◽  
Ionic Composition ◽  
Chloride Ions ◽  
Factors Influencing ◽  
Two Factors ◽  
Human Plasminogen

SummaryNative human plasminogen, the proenzyme of plasmin (E. C. 3.4.21.7) occurs in blood in two well defined forms, affinity forms I and II. In this paper, the feasibility of separating these forms of human native plasminogen by affinity chromatography, is shown to be dependent on two factors: 1) the ionic composition of the buffer containing the displacing agent: buffers of varying contents of sodium, Tris, phosphate and chloride ions were compared, and 2) the type of adsorbent. Two adsorbents were compared: Sepharose-lysine and Sepharose-bisoxirane-lysine. Only in the phosphate containing buffers, irrespective of the type of adsorbent, the affinity forms can be separated. The influence of the adsorbent can be accounted for by a large difference in dissociation constants of the complex between plasminogen and the immobilized lysine.

Effect of Formic Acid on Corrosion Behavior of STBA24 Low-Alloyed Steel and Its Weldment in Simulated Boiler Water Containing Chloride Ions

2020 ◽  
Vol 61 (9) ◽  
pp. 1775-1781
Author(s):  
Li-Bin Niu ◽  
Shoichi Kosaka ◽  
Masaki Yoshida ◽  
Yusuke Suetake ◽  
Kazuo Marugame
Keyword(s):  
Formic Acid ◽  
Corrosion Behavior ◽  
Chloride Ions ◽  
Alloyed Steel ◽  
Boiler Water ◽  
Low Alloyed Steel

Molecular Characterization of the Surface Excess Charge Layer in Droplets

2020 ◽  
Author(s):  
Victor Kwan ◽  
Styliani Consta
Keyword(s):  
Hydrogen Bonds ◽  
Surface Charge ◽  
Droplet Size ◽  
Chloride Ions ◽  
Total Charge ◽  
Excess Charge ◽  
Surface Excess ◽  
High Concentration ◽  
Dipole Orientation ◽  
Charge Layer

<div>Charged droplets play a central role in native mass spectrometry, atmospheric aerosols and in serving as micro-reactors for accelerating chemical reactions. The surface excess charge layer in droplets has often been associated with distinct chemistry. Using molecular simulations for droplets with Na+ and Cl- ions we have found that this layer is ≈ 1.5−1.7 nm thick and depending on the droplet size it includes 33%-55% of the total number of ions. Here, we examine the effect of droplet size and nature of ions in the structure of the surface excess charge layer by using molecular dynamics. We find that in the presence of simple ions the thickness of the surface excess charge layer is invariant not only with respect to droplet size but also with respect to the nature of the simple ions and it is not sensitive to fine details of different force fields used in our simulations.</div><div> In the presence of macroions the excess surface charge layer may extend to 2.0. nm. For the same droplet size, iodide and model hydronium ions show considerably higher concentration than the sodium and chloride ions. <br></div><div>We also find that differences in the average water dipole orientation in the presence of cations and anions in this layer are reflected in the charge distributions. Within the surface charge layer, the number of hydrogen bonds reduces gradually relative to the droplet interior where the number of hydrogen bonds is on the average 2.9 for droplets of diameter < 4 nm and 3.5 for larger droplets. The decrease in the number of hydrogen bonds from the interior to the surface is less pronounced in larger droplets. In droplets with diameter < 4 nm and high concentration of ions the charge of the ions is not compensated only by the solvent polarization charge but by the total charge that also includes the other free charge. This finding shows exceptions to the commonly made assumption that the solvent compensates the charge of the ions in solvents with very high dielectric constant. The study provides molecular insight into the bi-layer droplet structure assumed in the equilibrium partitioning model of C. Enke and assesses critical assumptions of the Iribarne-Thomson model for the ion-evaporation mechanism. <br></div>

Sign in / Sign up

Export Citation Format

Share Document