Simulation Studies of Hydrogen Ion reflection from Tungsten for the Surface Production of Negative Hydrogen Ions

2011 ◽  
Author(s):  
Takahiro Kenmotsu ◽  
Motoi Wada ◽  
Yasuhiko Takeiri ◽  
Katsuyoshi Tsumori
Keyword(s):  
Hydrogen Ion ◽  
Simulation Studies ◽  
Hydrogen Ions ◽  
Surface Production

Hydrogen Ion Beam Processing of Single Crystal Diamond Chips

1994 ◽  
Vol 354 ◽  
Author(s):  
Shuji Kiyohara ◽  
Iwao Miyamoto
Keyword(s):  
Surface Roughness ◽  
Single Crystal ◽  
Incidence Angle ◽  
Ion Beam ◽  
Etching Rate ◽  
Hydrogen Ion ◽  
Hydrogen Ions ◽  
Ion Beam Etching ◽  
Single Crystal Diamond ◽  
Before And After

AbstractIn order to apply ion beam etching with hydrogen ions to the ultra-precision processing of diamond tools, hydrogen ion beam etching characteristics of single crystal diamond chips with (100) face were investigated. The etching rate of diamond for 500 eV and 1000 eV hydrogen ions increases with the increase of the ion incidence angle, and eventually reaches a maximum at the ion incidence angle of approximately 50°, then may decrease with the increase of the ion incidence angle. The dependence of the etching rate on the ion incidence angle of hydrogen ions is fairly similar to that obtained with argon ions. Furthermore, the surface roughness of diamond chips before and after hydrogen ion beam etching was evaluated using an atomic force microscope. Consequently, the surface roughness after hydrogen ion beam etching decreases with the increase of the ion incidence angle within range of the ion incidence angle of 60°.

Reactions with Hydrogen Ions

1997 ◽  
Author(s):  
F. S. Zhang ◽  
T. R. Yu
Keyword(s):  
Ionization Energy ◽  
Alkali Metals ◽  
Chemical Properties ◽  
Hydrogen Ion ◽  
Hydrogen Ions ◽  
Soil Particles ◽  
Variable Charge ◽  
Hydrated Proton ◽  
Characteristic Features ◽  
Variable Charge Soils

Hydrogen ion is one kind of cation which possesses many properties common to all cations. Hydrogen ion also has its own characteristic features which are of particular significance for variable charge soils. The interactions between hydrogen ions and the surface of soil particles is the basic cause of the variability of both positive and negative surface charges of variable charge soils. The quantity of hydrogen ions in soils determines the acidity of the soil while the acidity of variable charge soils is among the strongest in all the soils. This strong acidity of variable charge soils affects many other chemical properties of the soil. In this chapter, the basic properties of hydrogen ions will be briefly discussed. Then, the products and the kinetics of the interaction between hydrogen ions and variable charge soils will be treated. The dissociation of hydrogen ions from the surface of soil particles has already been mentioned in Chapter 2. After the dissociation of an electron, a hydrogen atom becomes a proton (H+ ion). The ionization energy of hydrogen atoms is 1310 kj mol-1, whereas those of alkali metals, Li, Na, K, and Cs, are 519, 494, 419 and 377 kj mol-1, respectively. This difference in the ionization energy between hydrogen and alkali metals indicates that protons have a particularly strong affinity for electrons. Therefore, protons are apt to form a covalent bond with other atoms by sharing a pair of electrons, or to form a hydrogen bond. Because of the absence of an electronic shell, a proton has a diameter of the order of 10-13 cm, while other ions with electronic shells generally have a diameter of the order of 10-8 cm. Because a proton is so small, it is quite accessible to its neighboring ions and molecules. Therefore, there is very little steric hindrance when protons participate in chemical reactions. The above-mentioned features of proton are the basis for its particular properties. Free proton in solution is extremely unstable because it is very active. In an aqueous solution it will react with water molecules to form a hydrated proton, H3O+.

scholarly journals THE INFLUENCE OF SALTS UPON THE IONISATION OF EGG ALBUMIN

1927 ◽  
Vol 8 (6) ◽  
pp. 543-599 ◽  
Author(s):  
S. P. L. Sørensen ◽  
K. Linderstrøm-Lang ◽  
Ellen Lund
Keyword(s):  
Experimental Determination ◽  
Ammonium Chloride ◽  
Salt Concentration ◽  
Hydrogen Ion ◽  
Hydrogen Ions ◽  
Egg Albumin ◽  
Ion Activity ◽  
The Mean ◽  
Acids And Bases

Introduction. A description is given of the principle followed in the experimental determination of the ionisation of egg albumin, its capacity to combine with acids and bases. Egg albumin is regarded as an ampholyte, and in accordance with J. N. Brønsted's definition of acids and bases, ampholytes are considered as substances capable of both taking up and giving off hydrogen ions. The theoretical treatment of the capacity of ampholytes to combine with acids (and bases) has been carried out on this basis. Section A. Several experimental series are noted, comprising the determination of the activity coefficient of the hydrogen ion (fH) in ammonium chloride solutions of different concentration. Section B. The general method of experimental determination of the ionisation (capacity to combine with adds and bases) of egg albumin in ammonium chloride and potassium chloride solutions is briefly described, and the results of the experiments are compared. Section C. 1). In a brief theoretical survey we have suggested that distinction should be made between isoelectric and isoionic reaction of an ampholyte, the former defined as the hydrogen ion activity (value of paH) at which the mean valency of the ampholyte is 0, the latter as the hydrogen ion activity at which the quantity of acid or base combined with the ampholyte is 0; or, as we prefer to express it, the hydrogen ion activity at which the specific hydrogen ionisation of the ampholyte is 0. If the ampholyte does not combine with other ions than the hydrogen ion, then isoelectric and isoionic reaction coincide. Isoionic reaction is determined by acid-combining experiments. The principle of this determination is briefly described. A theoretical investigation of the alteration with salt concentration of both isoelectric (isoionic) reaction and the shape and direction of the ionisation curves is made, with regard to ampholytes capable only of combining with hydrogen ions, on the basis of the Debye-Hückel formulæ and Linderstrøm-Lang's theory for the ionisation of polyvalent ampholytes of simple type. It is shown that the salt effect, in accordance with the theory, and in qualitative agreement with the experiments, consists in a turning of the ionisation curves, indicating the relation between the quantity of combined acid (specific hydrogen ionisation) and paH, and the turning of the curves, which leaves the isoelectric reaction unaltered, tends in such a direction that the quantity of combined acid at constant ampholyte concentration and constant pan increases with increasing salt concentration. The possibility of chemical combining of other ions than the hydrogen ion is discussed. 2). Following on 1), a brief survey of the experimental results is given. 3). The isoionic reaction is found from the experimental material and proved to be independent of the ammonium chloride concentration. As the mean of all determinations we have paH0 = 4.898 (isoionic reaction). The difference between this value and that formerly found for ammonium sulphate solutions (4.844) is discussed. 4). Finally, on the basis of the theory in Section 1), some simple calculations of the ionisation curves for egg albumin are made, and it appears that the theory can reproduce the experimental results in a rough quantitative way when we assume that the egg albumin has a radius of 2.21·10–7 cm. (answering to a molecular weight of 35,000 in aqueous solution), and contains 30 acid and base groups.

scholarly journals The Hydrogen Ion Concentration in the Gut of certain Lamellibranchs and Gastropods

1925 ◽  
Vol 13 (4) ◽  
pp. 938-952 ◽  
Author(s):  
O. M. Yonge
Keyword(s):  
Mantle Cavity ◽  
Mya Arenaria ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Pecten Maximus ◽  
Hydrogen Ions ◽  
Acid Media ◽  
Hydrogen Ion Concentration ◽  
Acid Reaction ◽  
Acid Region

1. In the Lamellibranchs, as typified by Pecten maximus, Mya arenaria and Ensis siliqua, the entire, gut has an acid reaction, the stomach being the most acid region and the pH rising along the mid-gut and rectum.2. The origin of the acidity of the gut lies in the style. This has a low pH (5·4 in Pecten and Mytilus, 4·6 in Ensis and 4·45 in Mya), and, after it has been artificially extracted from Mya or induced to disappear, by keeping the animals under abnormal conditions, in Mytilus, Tapes and Pecten, the pH of the stomach invariably rises (by as much as 0·825 in Mya and 0·72 in Tapes), although the pH in the mantle cavity has fallen.3. The style, which dissolves rapidly in alkaline or weakly acid media, is not dissolved in fluids below a certain pH—4·4 for Ensis, 4·2 for Mya, 3·6 for Pecten and Mytilus.4. The style is never absent, even though animals are starved, so long as they are kept under otherwise healthy conditions. The disappearance of the style under abnormal conditions is probably due to a lowering of the vital activities, which include the secretion of the style substance, and the consequent dissolution of the style by the less acid contents of the stomach.5. The style is only maintained as a result of a balance between the rate of its secretion and the rate of its dissolution.6. There is a well-marked correlation between the tolerance of the presence of hydrogen ions possessed by the cilia from the various regions of the gut and the degree of acidity of the fluid with which they are normally surrounded.7. The pH of the gut in five Gastropods has been investigated. The fore-gut and stomach have invariably the lowest pH.8. This acidity may be caused by the salivary glands (Patella and Buccinum), the digestive gland (Doris and Aplysia), or the style (Crepidula).9. The mid-gut and rectum have a high pH, except in Doris, where there is little secretion of mucus, the gut being free and muscular.10. The style of Orepidula has similar properties to those of the Lamellibranchs. It has a pH of 5·8, and is not dissolved in fluid of pH 3·6 or lower.11. The cilia from the gut of Buccinum and Doris can function in a pH of 5·0, but there is little difference in the toleration of the various cilia to the presence of hydrogen ions.

Alveolar hypercapnia augments pulmonary C-fiber responses to chemical stimulants: role of hydrogen ion

2002 ◽  
Vol 93 (1) ◽  
pp. 181-188 ◽  
Author(s):  
Qihai Gu ◽  
Lu-Yuan Lee
Keyword(s):  
Hydrogen Ion ◽  
Right Atrial ◽  
Mechanical Stimuli ◽  
Hydrogen Ions ◽  
Lung Inflation ◽  
C Fibers ◽  
Arterial Blood ◽  
Blood Ph ◽  
C Fiber

To determine whether the excitabilities of pulmonary C fibers to chemical and mechanical stimuli are altered by CO2-induced acidosis, single-unit pulmonary C-fiber activity was recorded in anesthetized, open-chest rats. Transient alveolar hypercapnia (HPC) was induced by administering CO2-enriched gas mixture (15% CO2, balance air) via the respirator inlet for 30 s, which rapidly lowered the arterial blood pH from a baseline of 7.40 ± 0.01 to 7.17 ± 0.02. Alveolar HPC markedly increased the responses of these C-fiber afferents to several chemical stimulants. For example, the C-fiber response to right atrial injection of the same dose of capsaicin (0.25–1.0 μg/kg) was significantly increased from 3.07 ± 0.70 impulses/s at control to 8.48 ± 1.52 impulses/s during HPC ( n = 27; P < 0.05), and this enhanced response returned to control within ∼10 min after termination of HPC. Similarly, alveolar HPC also induced significant increases in the C-fiber responses to right atrial injections of phenylbiguanide (4–8 μg/kg) and adenosine (0.2 mg/kg). In contrast, HPC did not change the response of pulmonary C fibers to lung inflation. Furthermore, the peak response of these C fibers to capsaicin during HPC was greatly attenuated when the HPC-induced acidosis was buffered by infusion of bicarbonate (1.36–1.82 mmol · kg−1 · min−1 for 35 s). In conclusion, alveolar HPC augments the responses of these afferents to various chemical stimulants, and this potentiating effect of CO2 is mediated through the action of hydrogen ions on the C-fiber sensory terminals.

Experimental analysis of hydrogen ion diffusion in gastrointestinal mucus glycoprotein

1981 ◽  
Vol 240 (2) ◽  
pp. G176-G182 ◽  
Author(s):  
C. J. Pfeiffer
Keyword(s):  
Protective Action ◽  
Diffusion Chamber ◽  
Hydrogen Ion ◽  
Hydrogen Ions ◽  
Ion Diffusion ◽  
Flux Chamber ◽  
Linear Diffusion ◽  
Mucus Glycoprotein ◽  
Diffusion Of Hydrogen ◽  
Mucus Glycoproteins

Experiments were undertaken to test the hypothesis that mucus glycoproteins retard the diffusion of hydrogen ions, a possible protective action of gastric mucus. Mucus and mucus glycoproteins (visible mucus, crude mucin, mucus glycoprotein fractions) were evaluated in two devices designed for this test, a linear diffusion chamber and a hydrogen ion flux chamber. The linear diffusion chamber assessed ion diffusion from a point source through mucus glycoproteins to a H+ detector. A mathematical model of diffusion, based on Fick's law, was adapted to characterize diffusion in this chamber. The H+ flux chamber assessed H+ flux rates across a steep concentration gradient through controlled amounts of mucus glycoprotein. With the exception of human sulfomucin, tested only at dilute concentrations and only in the flux chamber, both procedures indicated that mucosubstances retarded, in a dose-related manner, diffusion of hydrogen ions. Experiments on buffering by crude porcine gastric mucin did not demonstrate significant buffering under physiological conditions. Thus, the present experimental data, the principles of which should be extrapolative to the mucous barrier at the biological level, suggest that mucus glycoproteins can in fact inhibit the diffusion of hydrogen ions.

Surface production of negative hydrogen ions

1992 ◽  
Author(s):  
M. Seidl ◽  
H. L. Cui ◽  
J. D. Isenberg ◽  
H. J. Kwon ◽  
B. S. Lee
Keyword(s):  
Hydrogen Ions ◽  
Surface Production

Memoirs: The Spermatheca of Loligo Vulgaris. I. Structure of the Spermatheca and Function of its Unicellular Glands

1938 ◽  
Vol s2-80 (320) ◽  
pp. 593-599
Author(s):  
G. J. van OORDT
Keyword(s):  
Sea Water ◽  
Goblet Cells ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Hydrogen Ions ◽  
Hydrogen Ion Concentration ◽  
Loligo Vulgaris ◽  
And Function

The structure of the spermatheca of Loligo vulgaris is described; it lies on the inner wall of the buccal membrane and within it large quantities of inactive spermatozoa are stored. This inactivity of the spermatozoa within the spermatheea is attributed to the effect of the secretion of the goblet-cells, situated as unicellular glands on the inner wall of the spermatheca. Inactive spermatozoa from the spermatheca become very active in sea-water, but are immobilized again after a few moments' contact with the pulp of the spermatheca contents. The hydrogen-ion concentration of the spermatheca contents is approximately 6.06; and, since spermatozoa become inactive in sea-water, the hydrogen-ion concentration of which is increased to this level, it seems probable that the inactivity of the spermatozoa within the spermatheca is due to the presence of hydrogen-ions. The spermatheca is functionally comparable to the mammalian epididymis.

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