Oxygen-induced high diffusion rate of magnesium dopants in GaN/AlGaN based UV LED heterostructures

2018 ◽  
Vol 20 (20) ◽  
pp. 13890-13895 ◽  
Author(s):  
Paweł Piotr Michałowski ◽  
Sebastian Złotnik ◽  
Jakub Sitek ◽  
Krzysztof Rosiński ◽  
Mariusz Rudziński
Keyword(s):  
Diffusion Rate ◽  
Uv Led ◽  
High Diffusion ◽  
High Diffusion Rate

Oxygen breaks up Mg–H complexes and induces high diffusion of Mg in GaN/AlGaN heterostructures.

scholarly journals Improved impregnation efficiency and pulp yield of softwood kraft pulp by high effective alkali charge in the impregnation stage

Holzforschung ◽  
2016 ◽  
Vol 70 (11) ◽  
pp. 1031-1037 ◽  
Author(s):  
Elisabet Brännvall ◽  
Marie Bäckström
Keyword(s):  
Kraft Pulp ◽  
Yield Loss ◽  
Diffusion Rate ◽  
Pulp Yield ◽  
Yield Increase ◽  
High Diffusion ◽  
High Diffusion Rate ◽  
Rapid Loading ◽  
Softwood Kraft Pulp

Abstract A pulp yield increase up to 2% can be achieved by impregnation with a liquor containing 2 M effective alkali (EA) concentration instead of 1 M. The yield increase is due to higher cellulose and glucomannan contents in the pulp, which can be rationalized by less yield loss by peeling, as impregnation is more effective at an elevated EA level. A rapid loading of chips with alkali can be realized due to a high diffusion rate. When the temperature becomes higher in the cooking stage, enough alkali is available for delignification reactions without the risk of alkali depletion in the chip core, so that the delignification is more homogeneous.

Surface ligand-mediated isolated growth of Pt on Pd nanocubes for enhanced hydrogen evolution activity

2015 ◽  
Vol 3 (47) ◽  
pp. 23660-23663 ◽  
Author(s):  
Fumin Ren ◽  
Haiyuan Lu ◽  
Haotian Liu ◽  
Zheng Wang ◽  
Yuen Wu ◽  
...  
Keyword(s):  
Hydrogen Evolution ◽  
Diffusion Rate ◽  
Growth Mode ◽  
Island Growth ◽  
Mode Structure ◽  
High Diffusion ◽  
High Diffusion Rate ◽  
Layered Growth ◽  
Surface Ligand ◽  
Free Area

Br− ions can affect the growth mode of Pt on a Pd substrate. When Br− ions adsorb on some sites of the Pd cube, the newly formed Pt atoms tended to grow on the Br− free area, facilitating island growth mode. Otherwise, without Br− ions, because of the relatively high diffusion rate between Pt and Pd, Pt atoms can epitaxially deposit on the whole surface of the Pd nanocubes, forming a layered growth mode structure.

Nitrogen-Doped Graphene Nanoscroll Foam with High Diffusion Rate and Binding Affinity for Removal of Organic Pollutants

Small ◽  
2017 ◽  
Vol 13 (14) ◽  
pp. 1603779 ◽  
Author(s):  
Qile Fang ◽  
Xufeng Zhou ◽  
Wei Deng ◽  
Yuewen Liu ◽  
Zhi Zheng ◽  
...  
Keyword(s):  
Binding Affinity ◽  
Organic Pollutants ◽  
Diffusion Rate ◽  
Nitrogen Doped ◽  
High Diffusion ◽  
High Diffusion Rate ◽  
Nitrogen Doped Graphene ◽  
Doped Graphene

Osmotic Conductance of the Peritoneum in Capd Patients with Permanent Loss of Ultrafiltration Capacity

1996 ◽  
Vol 16 (5) ◽  
pp. 488-496 ◽  
Author(s):  
Jacek Waniewski ◽  
Olof Heimbürger ◽  
Andrzej Werynski ◽  
Bengt Lindholm
Keyword(s):  
Linear Relationship ◽  
Absorption Rate ◽  
Diffusion Rate ◽  
Solute Diffusion ◽  
Time Model ◽  
High Diffusion ◽  
High Diffusion Rate ◽  
Permanent Loss ◽  
The Difference ◽  
Dialysate Volume

Objective To compare the effectiveness of osmotic pressure in the induction of fluid flow during continuous ambulatory peritoneal dialysis (CAPD) in patients with permanent loss of ultrafiltration capacity (UFC) and clinically stable patients. Design Estimation of osmotic conductance in individual CAPD patients using data from single CAPD dwell studies. Patients Twenty clinically stable CAPD patients with normal ultrafiltration rate (NUR group); 8 CAPD patients with permanent UFC loss due to high diffusion rate for small solutes [high diffusion rate (HDR) group]; 3 CAPD patients with permanent loss of UFC dueto high absorption rate (HAR) of peritoneal dialysate (HAR group). Design Six-hour dwell studies were carried out in each patient using 2 L of Dianeal 3.86% dialysis fluid. Dialysate volume and the peritoneal absorption rate were measured using radioiodinated serum albumin as a marker. The dialysate volume over dwell-time curves were examined using three mathematical models of fluid transport for solutions with a crystalloid osmotic agent: model P, based on a phenomenologically derived exponential function of time; model OS, based on the linear relationship between the rate of net volume change (Qv) to the difference of osmolality in dialysate and blood; and model G, based on the linear relationship between Qv and the difference of glucose concentration in dialysate and blood. Results All three models provided an accurate description of the measured dialysate volume over time curves. The osmotic conductance, defined as the coefficient of proportionality between the rate of ultrafiltration and the osmolality (or, alternatively, glucose) gradient between dialysate and blood plasma, was 30% lower in the HDR group than in the NUR group, but close to the normal value in the HAR group. Conclusion In the HDR group the changes in the peritoneal membrane, which resulted in the increased diffusion rate of small solutes, also yielded a decrease of osmotic conductance. In contrast, the changes in the membrane in the HAR group, which resulted in increased peritoneal absorption, did not change the osmotic con ductance or the solute diffusion rate. The detailed pathophysiological mechanisms for these two different types of UFC loss failure are still unknown.

Optimisation of Diffusion Bonding Parameters of Ti Alloys through the Structure and Surface Conditions

2014 ◽  
Vol 783-786 ◽  
pp. 2845-2850 ◽  
Author(s):  
Evgenia Yakushina ◽  
Aleksey Reshetov ◽  
Andrzej Rosochowski
Keyword(s):  
Diffusion Bonding ◽  
Diffusion Rate ◽  
Surface Condition ◽  
Coarse Grained ◽  
Initial Structure ◽  
Bonding Parameters ◽  
Ti Alloys ◽  
Ultrafine Grained ◽  
High Diffusion Rate

Diffusion bonding of Ti-6Al-4V titanium alloy in the coarse grained and ultrafine grained state was performed. The effect of initial structure and surface condition, as well as temperature and time, on the quality of joints was established. It is shown that, due to low-temperature superplasticity and high diffusion rate, samples with ultrafine grained structure demonstrate better bondability than coarse grained samples

Ferrian high sanidine in a lamproite from Cancarix, Spain

1993 ◽  
Vol 57 (387) ◽  
pp. 289-299 ◽  
Author(s):  
Kees Linthout ◽  
Wim J. Lustenhouwer
Keyword(s):  
Solid Solution ◽  
Structural State ◽  
Defect Structure ◽  
Diffusion Rate ◽  
High Rate ◽  
Nonstoichiometric Composition ◽  
Low Viscosity ◽  
High Diffusion Rate ◽  
Retrograde Boiling ◽  
Residual Melt

AbstractNa-poor, Fe-bearing high sanidine from a lamproite near Cancarix (Spain) has 2Vα‖(010) = 37-43° and C2/m, a = 8.598(15), b = 13.050(26), c = 7.209(17) Å, β = 116.00(18)° V = 727(2) Å3. Rims of sanidine crystals against vugs contain up to 60 mole % KFeSi3O8 and up to 10 at.% Si and 6 at.% K above the stoichiometric requirement; otherwise, they have up to 4 mole % □Si4O8 and 3 mole % K2O.Si4O8 in solid solution. Their MgO content may reach 0.46 wt.%. The skeletons of mm sized blocky crystals (Baveno habit) indicate formation under moderate undercooling at temperatures not much above 725°C Feldspar formation was facilitated by a high diffusion rate due to low viscosity in a highly perpotassic melt, supersaturated by pressure release and diopside fractionation, upon extrusion of a huge volume of lava in a crater. After titanian potassium-richterite largely filled the interstices in the sanidine fabric, crystals of dalyite (K2ZrSi6O15) and Fe-rich rims of sanidine and amphibole crystals were formed from an increasingly hydrous, silicic, ferric, and peralkaline residual melt. High rate nonequilibrium crystallisation caused the incorporation of excess SiO2 and K2O in the defect structure of the sanidine. Retrograde boiling initiated the escape of volatiles, causing the quenching, by which the disordered structural state and the nonstoichiometric composition of the sanidine were preserved.

Microstructures, surface areas, and oxygen absorption of Ti and Ti–Zr–V films grown using glancing-angle sputtering

2008 ◽  
Vol 23 (2) ◽  
pp. 579-587 ◽  
Author(s):  
Chien-Cheng Li ◽  
Jow-Lay Huang ◽  
Ran-Jin Lin ◽  
Hong-Ping Lin ◽  
Ding-Fwu Lii ◽  
...  
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Diffusion Rate ◽  
Oxygen Absorption ◽  
Silicon Substrates ◽  
Surface Areas ◽  
Porous Ti ◽  
High Diffusion Rate ◽  
Glancing Angle

Highly porous Ti and TiZrV getter film coatings have been successfully grown on (100) silicon substrates using the glancing-angle direct-current magnetron sputtering method. The evolution of the microstructures of the Ti and the TiZrV films strongly depends on the sputtering flux rate, surface diffusion rate, nucleation rate, compositions, and self-shadowing geometry of the nuclei on the sputtering flux. The larger the glancing angle, the higher the porosity and specific surface area of the Ti and TiZrV films. The weight-gain results strongly depend on several factors, such as specific surface area, the surface structure of the getter film, the diffusion rate of O in the getter film, the reactivity of Ti, Zr, and V on O, and the order of the stabilities of Ti, Zr, and V oxides on the film’s surface. Porous Ti film absorbs oxygen better than porous TiZrV film does due to its higher surface area and the high diffusion rate of O in Ti films.

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