Absorption time by a random trap distribution

1980 ◽  
Vol 21 (7) ◽  
pp. 1643-1645 ◽  
Author(s):  
Herbert B. Rosenstock
Keyword(s):  
Absorption Time

A temporal factorization at the maximum for certain positive self-similar Markov processes

2020 ◽  
Vol 57 (4) ◽  
pp. 1045-1069
Author(s):  
Matija Vidmar
Keyword(s):  
Markov Process ◽  
Laplace Transform ◽  
Markov Processes ◽  
Absorption Time ◽  
The Laplace Transform ◽  
Self Similar

AbstractFor a spectrally negative self-similar Markov process on $[0,\infty)$ with an a.s. finite overall supremum, we provide, in tractable detail, a kind of conditional Wiener–Hopf factorization at the maximum of the absorption time at zero, the conditioning being on the overall supremum and the jump at the overall supremum. In a companion result the Laplace transform of this absorption time (on the event that the process does not go above a given level) is identified under no other assumptions (such as the process admitting a recurrent extension and/or hitting zero continuously), generalizing some existing results in the literature.

Absorption Time of NegativeΣHyperons in Liquid Hydrogen

1965 ◽  
Vol 15 (15) ◽  
pp. 639-641 ◽  
Author(s):  
R. A. Burnstein ◽  
G. A. Snow ◽  
H. Whiteside
Keyword(s):  
Liquid Hydrogen ◽  
Absorption Time

scholarly journals Pengujian Zeolit Alam Mordenit Sebagai Penjerap Proses Pendegradasian Kandungan Amonium di dalam Air Tambak

2020 ◽  
Vol 21 (1) ◽  
pp. 49-55
Author(s):  
Nuryoto Nuryoto ◽  
Teguh Kurniawan ◽  
Indar Kustiningsih
Keyword(s):  
Particle Size ◽  
Natural Zeolite ◽  
The Other ◽  
Ammonium Concentration ◽  
Small Fish ◽  
Natural Zeolites ◽  
Absorption Time ◽  
Adsorption Time ◽  
Research Results ◽  
Other Hand

ABSTRACTIndonesia has an abundant quantity of natural zeolites that have not yet been utilized maximally. On the other hand, fishpond farmers have a problem regarding the presence of ammonium in the fishpond water which will negatively impact to survival of fish, especially small fish. To solve this problem, this research was utilizing natural zeolite to degrade ammonium in the fishpond water. This research aimed to test mordenite natural zeolite from Bayah as an adsorbent to collaborate some variables impact to reach more maximal adsorption. The variables that were used to be observed were: mordenite natural zeolite from Bayah as an adsorbent which has been activated by 1-7 N H2SO4 and the other was without activation, ammonium concentration of 80-800 ppm, the particle size of adsorbent of 80 and 150 mesh, stirring speed of 600 and 800 rpm, and without stirring by duration adsorption time of 60 minutes. The research results showed that mordenite natural zeolite after activated was able to adsorb of 100% ammonium, while for the mordenite natural zeolite from Bayah without stirring was of 80%, by the same absorption time. These results will give significant benefits for fishpond farmers to increase their productivity because of the increase in fish survival.Keywords: adsorption, adsorbent, zeolite, amoniumABSTRAKKandungan zeolit alam di Indonesia cukup melimpah dan belum termanfaatkan secara maksimal. Pada sisi lain petani tambak dihadapkan pada masalah terdapatnya kandungan amonium di dalam air tambak, yang akan berdampak negatif bagi keberlangsungan hidup ikan, terutama ikan yang masih kecil. Penelitian ini mencoba memanfaatkan zeolit alam guna mendegradasi kandungan amonium dalam air tambak. Tujuan penelitian ini adalah melakukan pengujian terhadap zeolit alam mordenit dari Bayah sebagai adsorben, baik dilakukan dengan pengadukan maupun tanpa pengadukan, serta mengkolaborasi beberapa variabel yang berpengaruh agar hasil adsorpsi lebih maksimal. Observasi dilakukan dengan zeolit alam mordenit dari Bayah yang telah diaktivasi dengan 1-7 N H2SO4 maupun tanpa aktivasi, rentang konsentrasi larutan amonium 80-800 ppm, ukuran partikel adsorben 80 dan 150 mesh, kecepatan pengadukan 600 dan 800 rpm, dan tanpa pengadukan serta lamanya waktu penyerapan 60 menit. Hasil penelitian menunjukan hasil yang sangat baik, dan secara umum zeolit alam mordenit Bayah teraktivasi telah mampu melakukan adsorpsi amonium sebesar 100%, sedangkan untuk zeolit alam mordenit Bayah tanpa pengadukan sebesar 80% pada waktu adsorpsi yang sama.Kata kunci: adsorpsi, adsorben, zeolit, amonium

scholarly journals Effect of Dye Absorption Time on the Performance of a Novel 2-HNDBA Sensitized ZnO Photo anode Based Dye-Sensitized Solar Cell

2020 ◽  
Author(s):  
Shital S. Rakhunde ◽  
◽  
Kisan M. Gadave ◽  
Dnyaneshwar R. Shinde ◽  
Pankaj K. Bhujbal ◽  
...  
Keyword(s):  
Solar Cell ◽  
Dye Sensitized Solar Cell ◽  
Absorption Time ◽  
Dye Sensitized ◽  
Dye Absorption

Cerebral gas embolism absorption during hyperbaric therapy: theory

2001 ◽  
Vol 90 (2) ◽  
pp. 593-600 ◽  
Author(s):  
Annette B. Branger ◽  
Christian J. Lambertsen ◽  
David M. Eckmann
Keyword(s):  
Decompression Sickness ◽  
Initial Step ◽  
External Pressure ◽  
Neurological Dysfunction ◽  
Inert Gas ◽  
Gas Embolism ◽  
Royal Navy ◽  
Absorption Time ◽  
Hyperbaric Therapy

Cerebral gas embolism is a serious consequence of diving. It is associated with decompression sickness and is assumed to cause severe neurological dysfunction. A mathematical model previously developed to calculate embolism absorption time based on in vivo bubble geometry is used in which various conditions of hyperbaric therapy are considered. Effects of varying external pressure and inert gas concentrations in the breathing mixtures, according to US Navy and Royal Navy diving treatment tables, are predicted. Recompression alone is calculated to reduce absorption times of a 50-nl bubble by up to 98% over the untreated case. Lowering the inhaled inert gas concentration from 67.5% to 50% reduces absorption time by 37% at a given pressure. Bubbles formed after diving and decompression with He are calculated to absorb up to 73% faster than bubbles created after diving and decompression with air, regardless of the recompression gas breathed. This model is a useful alternative to impractical clinical trials in assessing which initial step in hyperbaric therapy is most effective in eliminating cerebral gas embolisms should they occur.

Moments of Absorption Time for a Conditioned Random Walk

1979 ◽  
Vol 60 (1) ◽  
pp. 83-90 ◽  
Author(s):  
W. A. Beyer ◽  
M.S. Waterman
Keyword(s):  
Random Walk ◽  
Absorption Time

Moment formulas for the Markov renewal branching process

1976 ◽  
Vol 8 (4) ◽  
pp. 690-711 ◽  
Author(s):  
Marcel F. Neuts
Keyword(s):  
Steady State ◽  
Numerical Computation ◽  
Busy Period ◽  
Branching Process ◽  
Queueing Models ◽  
Absorption Time ◽  
The Mean ◽  
The Moment

There are many queueing models in which there appears a semi-Markov matrix G(·), whose entries are absorption-time distributions in a Markov renewal branching process. The role of G(·) is similar to that of the busy period in the simple M/G/1 model. The computation of various quantities associated with G(·) is however much more complicated. The moment matrices, and particularly the mean matrix of G(·), are essential in the construction of general and mathematically well-justified algorithms for the steady-state distributions of such queues.This paper discusses the moment matrices of G(·) and algorithms for their numerical computation. Its contents are basic to the algorithmic solutions to several queueing models, which are to be presented in follow-up papers.

scholarly journals Theoretical and experimental intravascular gas embolism absorption dynamics

1999 ◽  
Vol 87 (4) ◽  
pp. 1287-1295 ◽  
Author(s):  
Annette B. Branger ◽  
David M. Eckmann
Keyword(s):  
Spherical Shape ◽  
Neurological Dysfunction ◽  
Gas Embolism ◽  
Absorption Time ◽  
Large Numbers ◽  
Male Wistar Rats ◽  
End Caps ◽  
Using Data ◽  
Initial Geometry

Multifocal cerebrovascular gas embolism occurs frequently during cardiopulmonary bypass and is thought to cause postoperative neurological dysfunction in large numbers of patients. We developed a mathematical model to predict the absorption time of intravascular gas embolism, accounting for the bubble geometry observed in vivo. We modeled bubbles as cylinders with hemispherical end caps and solved the resulting governing gas transport equations numerically. We validated the model using data obtained from video-microscopy measurements of bubbles in the intact cremaster microcirculation of anesthetized male Wistar rats. The theoretical model with the use of in vivo geometry closely predicted actual absorption times for experimental intravascular gas embolisms and was more accurate than a model based on spherical shape. We computed absorption times for cerebrovascular gas embolism assuming a range of bubble geometries, initial volumes, and parameters relevant to brain blood flow. Results of the simulations demonstrated absorption time maxima and minima based on initial geometry, with several configurations taking as much as 50% longer to be absorbed than would a comparable spherical bubble.

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