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Calculations and Sensitivity Analysis of Chlorine-,NO_(x)-,and Bromine-Depleting Cycles of Stratospheric Ozone

Journal of Environmental Science and Engineering(B) 2024年第2期13卷 53-69页

作者： Ibraheem Alelmi Sen nieh Department of Mechanical Engineering the Catholic University of AmericaWashington DC 20064the United States College of Engineering Yuan Ze UniversityTaoyuan 32003Taiwan

this paper presents an engineering system approach using a 2D model of conservation of mass to study the dynamics of ozone and concerned chemical species in the *** considering all fourteen photolysis,ozone-generating,and-depleting chemical reactions,the model calculated the transient,spatial changes of ozone under different physical-chemical-radiative *** against the measured data demonstrated good accuracy,close match of our model with the observed ozone concentrations at both 20°S and 90°N *** deviation in the average concentration was less than 1% and in ozone profiles less than 17%.the impacts of various chlorine-(Cl),nitrogen oxides-(NO_(x)),and bromine-(Br)depleting cycles on ozone concentrations and distribution were *** chlorine catalytic depleting cycle was found to exhibit the most significant impact on ozone dynamics,confirming the key role of chlorine in the problem of ozone *** analysis was conducted with levels of 25%,50%,100%,200%,and 400% of the baseline *** combined cycles(Cl+NO_(x)+Br)showed the most significant influence on ozone *** total ozone abundance above the South Pole could decrease by a small 3%,from 281 DU(Dubson Units)to 273 DU for the 25% level,or by a huge thinning of 60%to 114 DU for the 400% concentration *** the level of chlorine gases increased beyond 200%,it would cause ozone depletion to a level of ozone hole(below 220 DU).the 2D Ozone Model presented in this paper demonstrates robustness,convenience,efficiency,and executability for analyzing complex ozone phenomena in the stratosphere.

关键词： Ozone depletion 2-D model chlorine bromine nitrogen oxides sensitivity analysis total ozone abundance DU

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2-D Modeling and Calculations of Stratospheric Ozone and Influences of Convection, Diffusion, and time

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Atmospheric and Climate Sciences 2024年第2期14卷 250-276页

作者： Ibraheem Alelmi Laurie Wei Sen nieh Department of Mechanical Engineering The Catholic University of America Washington DC USA School of Engineering The Catholic University of America Washington DC USA College of Engineering Yuan Ze University Taoyuan

An engineering system approach of 2-D cylindrical model of transient mass balance calculations of ozone and other concerned chemicals along with fourteen photolysis, ozone-generating and ozone-depleting chemical reaction equations was developed, validated, and used for studying the ozone concentrations, distribution and peak of the layer, ozone depletion and total ozone abundance in the stratosphere. the calculated ozone concentrations and profile at both the Equator and a 60˚N location were found to follow closely with the measured data. the calculated average ozone concentration was within 1% of the measured average, and the deviation of ozone profiles was within 14%. the monthly evolution of stratospheric ozone concentrations and distribution above the Equator was studied with results discussed in details. the influences of slow air movement in both altitudinal and radial directions on ozone concentrations and profile in the stratosphere were explored and discussed. Parametric studies of the influences of gas diffusivities of ozone DO3 and active atomic oxygen DO on ozone concentrations and distributions were also studied and delineated. Having both influences through physical diffusion and chemical reactions, the diffusivity (and diffusion) of atomic oxygen DO was found to be more sensitive and important than that of ozone DO3 on ozone concentrations and distribution. the 2-D ozone model present in this paper for stratospheric ozone and its layer and depletion is shown to be robust, convenient, efficient, and executable for analyzing the complex ozone phenomena in the stratosphere. .

关键词： Stratospheric Ozone 2-D Model Ozone Layer Ozone Depletion Convection Diffusion

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Effects of Chlorine and Chlorine Monoxide on Stratospheric Ozone Depletion

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Atmospheric and Climate Sciences 2024年第1期14卷 136-153页

作者： Laurie Wei Ibraheem Alelmi Sen nieh Department of Mechanical Engineering The Catholic University of America Washington DC USA

this paper presents a system approach of mass balance calculations of ozone and other species under diffusion-convection-reaction processes to study the impacts of major ozone-depleting chemicals, chlorine (Cl) and chlorine monoxide (ClO), and the effect of photolysis on ozone concentrations, ozone depletion, total ozone abundance, and ozone layer along the altitude in the stratosphere. the calculated ozone concentrations and profile of the layer followed a similar trend and were generally in good agreement with the measurements above the tropical area. the calculated peak of the layer was at the same mid-stratosphere at Z = 30 km with a peak concentration and total ozone abundance about 20% higher than the measured peak concentration of 8.0 ppm and total abundance of 399 DU. In the presence of Cl and ClO, the calculated ozone concentrations and total abundance were substantially reduced. Cl generally depleted more uniformly of ozone across the altitude, while ClO reduced substantially the ozone in the upper stratosphere and thus shifted the peak of the layer to a much lower elevation at Z = 14 km. Although both ClO and Cl are active ozone-depleting chemicals, ClO was found to have a more pronounced impact on ozone depletion and distribution than Cl. the possible explanations of these interesting phenomena were discussed and elaborated. the approach and calculations in this paper were shown to be useful in providing an initial insight into the structure and behavior of the complex ozone layer.

关键词： Ozone Ozone Depletion Chlorine Chlorine Monoxide Photolysis Dobson Unit

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Experimental investigation on slip conditions during thread rolling with flat dies

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Friction 2024年第1期12卷 136-143页

作者： Stefan VOLZ peter GROCHE Institute for Production Engineering and Forming Machines Technical University DarmstadtOtto-Berndt Straße 2Darmstadt 64287Germany

the process design of flat die rolling operations can be a tedious and costly process due to the challenges posed by small process *** this work,an effort is made to closely investigate and understand the process limits caused by excessive slippage of the *** measurements are carried out to capture the characteristics of excessive slippage and the influence of the stroke rate and the tribological system on this process *** differences in slippage were observed,depending on the tribological *** systems with polymer based lubricants showed excessive slippage at low stroke rates,systems using oil or no lubricant endured higher stroke rates before process limits were *** optical measurements revealed three major forms of slippage:successful rolling without slippage,failure due to excessive slippage at process start,and failure due to excessive slippage at around one workpiece rotation.

关键词： rolling incremental forming thread rolling slippage profile rolling

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Skeletal muscle as a molecular and cellular biomarker of disease progression in amyotrophic lateral sclerosis:a narrative review

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Neural Regeneration Research 2024年第4期19卷 747-753页

作者： peter H.King Department of Neurology and Center for Neurodegeneration and Experimental therapeutics The University of Alabama at BirminghamBirminghamALUSA Birmingham Veterans Affairs Medical Center BirminghamALUSA

Amyotrophic lateral sclerosis is a fatal multisystemic neurodegenerative disease with motor neurons being a primary *** progressive weakness is a hallmark feature of amyotrophic lateral sclerosis,there is considerable heterogeneity,including clinical presentation,progression,and the underlying triggers for disease *** on longitudinal studies with families harboring amyotrophic lateral sclerosis-associated gene mutations,it has become apparent that overt disease is preceded by a prodromal phase,possibly in years,where compensatory mechanisms delay symptom *** 85-90%of amyotrophic lateral sclerosis is sporadic,there is a strong need for identifying biomarkers that can detect this prodromal phase as motor neurons have limited capacity for *** Food and Drug Administration-approved therapies work by slowing the degenerative process and are most effective early in the *** muscle,including the neuromuscular junction,manifests abnormalities at the earliest stages of the disease,before motor neuron loss,making it a promising source for identifying biomarkers of the prodromal *** accessibility of muscle through biopsy provides a lens into the distal motor system at earlier stages and in real *** advent of“omics”technology has led to the identification of numerous dysregulated molecules in amyotrophic lateral sclerosis muscle,ranging from coding and non-coding RNAs to proteins and *** technology has opened the door for identifying biomarkers of disease activity and providing insight into disease mechanisms.A major challenge is correlating the myriad of dysregulated molecules with clinical or histological progression and understanding their relevance to presymptomatic phases of *** are two major goals of this *** first is to summarize some of the biomarkers identified in human amyotrophic lateral sclerosis muscle that have a clinicopathological correlation with disease activi

关键词： amyotrophic lateral sclerosis biomarkers clinicopathological correlation disease progression muscle biomarkers neurogenic atrophy neuromuscular junction non-coding RNAs presymptomatic stages skeletal muscle SOD1G93A mouse model

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A product version of the Hilton-Milner-Frankl theorem

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Science China Mathematics 2024年第2期67卷 455-474页

作者： peter Frankl Jian Wang Alfréd Rényi Institute of Mathematics Hungarian Academy of SciencesBudapest H-1053Hungary Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

two families F and G of k-subsets of {1, 2,..., n} are called non-trivial cross t-intersecting if|F ∩ G|≥t for all F ∈ F, G ∈ G and | ∩ {F : F ∈ F}| < t, | ∩ {G : G ∈ G}| < t. In the present paper,we determine... 详细信息

two families F and G of k-subsets of {1, 2,..., n} are called non-trivial cross t-intersecting if|F ∩ G|≥t for all F ∈ F, G ∈ G and | ∩ {F : F ∈ F}| t, | ∩ {G : G ∈ G}| t. In the present paper,we determine the maximum product of the sizes of two non-trivial cross t-intersecting families of k-subsets of{1, 2,..., n} for n≥4(t + 2)2k2, k≥5, which is a product version of the Hilton-Milner-Frankl theorem.

关键词： extremal set theory cross t-intersecting family product version non-trivial

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A Population Dynamics Approach to the Distribution of Space Debris in Low Earth Orbit

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Communications on Applied Mathematics and Computation 2024年第1期6卷 340-353页

作者： John Jurkiewicz peter Hinow Department of Mathematical Sciences University of Wisconsin-MilwaukeeMilwaukeeWI53201USA

the presence of the debris in the Earth’s orbit poses a significant risk to human activity in outer *** debris population continues to grow due to ground launches,the loss of external parts from space ships,and uncontrollable collisions between objects.A computationally feasible continuum model for the growth of the debris population and its spatial distribution is therefore *** we propose a diffusion-collision model for the evolution of the debris density in the low-Earth orbit and its dependence on the ground-launch *** parametrize this model and test it against data from publicly available object catalogs to examine timescales for the uncontrolled ***,we consider sensible launch policies and cleanup strategies and how they reduce the future risk of collisions with active satellites or space ships.

关键词： Population dynamics Space debris Kessler syndrome Diffusion Low-Earth orbit

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Diagnostic tools for fecal incontinence: Scoring systems are the crucial first step

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World Journal of Gastroenterology 2024年第6期30卷 516-522页

作者： peter Liptak Martin Duricek peter Banovcin Clinic of Internal Medicine-Gastroenterology University Hospital in MartinJessenius Faculty of Medicine in MartinComenius UniversityMartin 03601Slovakia

the main aim of this editorial is to comment on the recent article published by Garg et al in the World Journal of Gastroenterology 2023;29:*** original research presents a new scoring system for fecal *** incontinence is a chronic disease with a severe impact on the quality of life of the *** social stigmatization often leads to significant underreporting of the condition even during visits to a specialist and could lead to further misman-agement or non-existent management of the *** important fact is that patients are often unable to describe their condition when not asked precisely defined *** problem is partially resolved by scoring *** scoring systems are commonly used;however,each of them has their *** example,the absence of different kinds of leakage besides flatus and stool could further lead to underscoring the incontinence ***,there has long been a call for a more precise scoring *** correct identification of the presence and severity of fecal incontinence is paramount for further diagnostic approach and for choosing the appropriate therapy *** editorial describes fecal incontinence,its effect on quality of life in general and further evaluates the diagnostic approach with a particular focus on symptom scoring systems and their implications for clinical practice.

关键词： Incontinence Fecal Scoring system Questionary Quality of life

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China, Malaysia, and an Emerging New World Order

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China Report ASEAN 2024年第7期9卷 32-33页

作者： peter t C Chang Institute of China Studies University of Malaya

the strong relationship between China and Malaysia can be a catalyst for advancing a more stable and representative world *** leveraging their close ties,both nations can collaborate on diplomatic initiatives,economic... 详细信息

关键词： order stability catalyst

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Optimization of product characteristics of porous carbon agglomerates using a design of experiments in fluidized bed agglomeration

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Particuology 2024年第6期89卷 258-269页

作者： Martin Oelofse Robert Rack Marcelle Hilden peter Langguth Department of Pharmaceutical technology and Biopharmaceutics Johannes Gutenberg UniversityMainzGermany Carbon Advanced Solutions GmbH HeuchelheimGermany

Spraying parameters during particle agglomeration processes can affect the agglomeration kinetics and particle *** study was conducted to better understand the influence of the spraying parameters in a fluidized bed wet agglomeration process,and the influence on the stability characteristics of carbon tablets.A formulation based on fine carbon and peroxide powder,as well as carboxymethyl cellulose as a binder,was used to produce agglomerates in a first production *** in a second production step carbon tablets with a high porosity were molded for the customer goods *** optimization of the compressive strength of these carbon tablets was the goal of the *** agglomerates were produced with a laboratory scale granulator called“ProCell”and were compressed with a five-cavity mechanical *** screening of the agglomeration process parameters and their influence on the agglomerates quality,as well as the performance characteristics of the carbon tablets,were investigated using a multilevel factorial *** experimental runs were done by varying atomized air pressure and feed rate of the *** was determined by the design *** findings of the statistical trials showed that low atomized air pressure and a low feed rate lead to a higher tablet compressive strength.

关键词： Wet agglomeration Fluidized bed Design of experiments Carbon agglomerates and tablets

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