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A combination of density-based clustering method and DEM to numerically investigate the breakage of bonded pharmaceutical granules in the ball milling process

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Particuology 2021年第5期19卷 153-168页

作者： Alexander Krok peter Peciar Kieran Coffey keith Bryan Sandra Lenihan Department of Process Energy and Transport EngineeringMunster Technological UniversityBishopstownCork T12 P928Ireland Department of Mechanical Biomedical and Manufacturing EngineeringMunster Technological UniversityBishopstownCork T12 P928Ireland Pfizer Newbridge LittleconnellNewbridgeCo.Kildare W12 HX57Ireland Institute of Process Engineering Faculty of Mechanical EngineeringSlovak University of TechnologyNam.Slobody 1781231 BratislavaSlovakia

Ball milling is widely used in industry to mill particulate *** primary purpose of this process is to attain an appropriate product size with the least possible energy *** process is also extensively utilised in pharmaceuticals for the comminution of the excipients or ***,for ball mill,little is known concerning the mechanism of size *** prediction approaches are not deemed useful to provide significant insights into the operation or facilitate radical step changes in ***,the discrete element method(DEM)as a computational modelling approach has been used in this *** previous research,DEM has been applied to simulate breaking behaviour through the impact energy of all ball collisions as the driving force for ***,the nature of pharmaceutical material fragmentation during ball milling is more *** functional equations which link broken media and applied energy do not consider the collision of particulate media of different shapes or collisions of particulate media(such as granules)with balls and rotating mill *** could have a significant impact on ***,this paper aimed to investigate the fragmentation of bounded particles into DEM granules of different shape/size during the ball milling process.A systematic study was undertaken to explore the effect of milling speed on breakage ***,in this study,a combination of a density-based clustering method and discrete element method was employed to numerically investigate the number and size of the fragments generated during the ball milling process over *** was discovered that the collisions of the ball increased proportionally with rotation speed until reaching the critical rotation ***,results illustrate that with an increase of rotation speed,the mill power increased *** caratacting motion of mill material together with balls was identified as the most

关键词： Ball milling Granular pharmaceutical lactose Density-based clustering Discrete element method Breakage Mill rotation speed ABAQUS

Complementary Physical and Mechanical Techniques to Characterise Tooth: A Bone-like Tissue

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Journal of Bionic Engineering 2006年第1期3卷 19-31页

作者： peter Zioupos keith D. Rogers Centre for Photo-manipulation and Photo-analysis of Materials Cranfield University Shrivenham SN 6 8LA UK Centre for Materials Science and Engineering Cranfield University Postgraduate Medical School Shrivenham SN 6 8LA UK

Bone like tissues are biocomposites comprising an organic matrix （mostly collagen） and a reinforcement phase in the form of mineral crystals （poorly stoichiometric apatite）. The composite properties are a result of the material characteristics of the two phases, their interaction, the relative composition, the orientation and the micro-architecture of the structure. The inherent spatial heterogeneity of these tissues （a result of evolutionary and functional requirements） and their exposure to various environmental and mechanical influences result in highly variable properties on the microscale, which can only be characterised by modern microanalytical methods. We present here results obtained by the complementary use of the modem nanoindentation and micro-X-ray diffraction techniques, which were used to probe the properties and structure of human dentine and enamel of primary molar teeth. The results show that both the addition and the higher organization of mineral within the organic matrix produce stiffer and harder tissue and that the examination of properties within small tissue volumes can be reliably achieved by use of these two methods in parallel. This opens new avenues in the study of biomaterial in general, and for the local characterisation of regions of teeth that suffered bacterial attack, mechanical wear, fluoridisation, chemical bleaching, or dental treatment such as laser ablation or drilling.

关键词： biogenic composites teeth nanoindentation hardness X-ray diffraction

Theory of a Mach Effect Thruster I

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Journal of Modern Physics 2015年第11期6卷 1510-1525页

作者： Heidi Fearn Adam Zachar keith Wanser James woodward Department of Physics California State University Fullerton Fullerton USA School of Engineering & Applied Science University of Pennsylvania Philadelphia USA

The Mach Effect Thruster (MET) is a propellant—less space drive which uses Mach’s principle to produce thrust in an accelerating material which is undergoing mass—energy fluctuations, [1]-[3]. Mach’s principle is a statement that the inertia of a body is the result of the gravitational interaction of the body with the rest of the mass-energy in the universe. The MET device uses electric power of 100 - 200 Watts to operate. The thrust produced by these devices, at the present time, are small on the order of a few micro-Newtons. We give a physical description of the MET device and apparatus for measuring thrusts. Next we explain the basic theory behind the device which involves gravitation and advanced waves to incorporate instantaneous action at a distance. The advanced wave concept is a means to conserve momentum of the system with the universe. There is no momentun violation in this theory. We briefly review absorber theory by summarizing Dirac, Wheeler-Feynman and Hoyle-Narlikar (HN). We show how woodward’s mass fluctuation formula can be derived from first principles using the HN-theory which is a fully Machian version of Einstein’s relativity. HN-theory reduces to Einstein’s field equations in the limit of smooth fluid distribution of matter and a simple coordinate transformation.

关键词： Mach Effect Drive Transient Mass Fluctuations Weak Field Limit Gravitation Modified (PPN) Parameterized Post Newtonian Approximation Linearized Einstein Equations Gravitoelectromagnetism

Not Ready for Convergence in Data Infrastructures

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Data Intelligence 2021年第1期3卷 116-135页

作者： keith Jeffery peter Wittenburg Larry Lannom George Strawn Claudia Biniossek Dirk Betz Christophe Blanchi keith G Jeffery Consultants 71 Gilligans WayFaringdon SN77FXUK Max Planck Computing and Data Facility Gießenbachstraße 285748 GarchingGermany Corporation for National Research Initiatives(CNRI) RestonVirginia 20191USA US National Academy of Sciences Washington DC 20418USA GESIS-Leibniz Institute for the Social Sciences Unter Sachsenhausen 6-850667CologneGermany Corporation for National Research Initiatives RestonVirginia 20191USA

Much research is dependent on Information and Communication Technologies(ICT).Researchers in different research domains have set up their own ICT systems(data labs)to support their research,from data collection(observation,experiment,simulation)through analysis(analytics,visualisation)to ***,too frequently the Digital Objects(DOs)upon which the research results are based are not curated and thus neither available for reproduction of the research nor utilization for other(e.g.,multidisciplinary)research *** key to curation is rich metadata recording not only a description of the DO and the conditions of its use but also the provenance-the trail of actions performed on the DO along the research *** are increasing real-world requirements for multidisciplinary *** DOs in domain-specific ICT systems(silos),commonly with inadequate metadata,such research is *** wide agreement on principles for achieving FAIR(findable,accessible,interoperable,and reusable)utilization of research data,current practices fall *** DOs offer a way *** paradoxes,barriers and possible solutions are *** key is persuading the researcher to adopt best practices which implies decreasing the cost(easy to use autonomic tools)and increasing the benefit(incentives such as acknowledgement and citation)while maintaining researcher independence and flexibility.

关键词： Scientific process Workflow Metadata FAIR Scientific data Data wrangling

Theory of a Mach Effect Thruster II

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Journal of Modern Physics 2015年第13期6卷 1868-1880页

作者： Heidi Fearn Nolan van Rossum keith Wanser James F. woodward Department of Physics California State University Fullerton Fullerton CA USA Department of Aerospace Engineering Iowa State University Ames IA USA

According to Einstein, General Relativity contains the essence of Mach’s ideas. Mach’s principle can be summarized by stating that the inertia of a body is determined by the rest of the mass-energy content of the universe. Inertia here arises from mass-energy there. The latter, was a statement made by John Wheeler in his 1995 book, Gravitation and Inertia, coauthored by Ciufolini. Einstein believed that to be fully Machian, gravity would need a radiative component, an action-at-a-distance character, so that gravitational influences on a body from far away could be felt immediately. In 1960’s, Hoyle and Narlikar (HN) developed such a theory which was a gravitational version of the Absorber theory derived by Wheeler-Feynman for classical electrodynamics and later expanded upon by Davies and Narlikar for quantum electrodynamics. The HN-field equation has the same type of mass fluctuation terms as in the woodward Mach effect thruster theory. The force equation, used to predict the thrust in our device, can be derived from the mass fluctuation. We outline a new method for deriving the force equation. We present new experimental tests of the thruster to show that the thrust seen in our device is not due to either heating or Dean Drive effects. Successful replications have been performed by groups in Austria and Canada, but their work is still pending in the peer review literature.

关键词： Mach Effect Drive Transient Mass Fluctuations Mach’s Principle Action at a Distance Advanced Waves Event Horizon

State of FAIRness in ESFRI Projects

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Data Intelligence 2020年第1期2卷 230-237,316页

作者： peter Wittenburg Franciska de Jong Dieter van Uytvanck Massimo Cocco keith Jeffery Michael Lautenschlager Hannes Thiemann Margareta Hellstrom Ari Asmi Petr Holub Max Planck Computing and Data Facility Gießenbachstraße 285748 GarchingGermany CLARIN ERIC CLARIN ERIC Drift 10Utrecht 3512 BSThe Netherlands EPOS ERIC Via di Vigna Murata 605Rome 00143Italy keith G Jeffery Consultants FaringdonUK DKRZ Ringgold standard institution Bundesstr.45aHamburgHamburg 20146Germany Department of Physical Geography and Ecosystem Ringgold standard institutionLund UniversityScienc Sölvegatan 12Lund 22362Sweden University of Helsinki Ringgold Standard Institution–Institution of Atmospheric and Earth System Sciences P.O.Box 64Helsinki 00014Finland BBMRI-ERIC Neue Stiftingtalstrasse 2/B/6 Graz 8010Austria

Since 2009 initiatives that were selected for the roadmap of the European Strategy Forum on Research Infrastructures started working to build research infrastructures for a wide range of research *** important result of the strategic discussions was that distributed infrastructure scenarios were now seen as“complex research facilities”in addition to,for example traditional centralised infrastructures such as *** this paper we look at five typical examples of such distributed infrastructures where many researchers working in different centres are contributing data,tools/services and knowledge and where the major task of the research infrastructure initiative is to create a virtually integrated suite of resources allowing researchers to carry out state-of-the-art *** analysis shows that most of these research infrastructures worked on the Findability,Accessibility,Interoperability and Reusability dimensions before the term“FAIR”was actually *** definition of the FAIR principles and their wide acceptance can be seen as a confirmation of what these initiatives were doing and it gives new impulse to close still existing *** initiatives also seem to be ready to take up the next steps which will emerge from the definition of FAIR maturity *** from these infrastructures should bring in their 10-years’experience in this definition process.

关键词： Infrastructure FAIR Metrics GO FAIR Matrix

Recovery of nickel,cobalt,copper and zinc in sulphate and chloride solutions using synergistic solvent extraction

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Chinese Journal of Chemical Engineering 2016年第2期24卷 237-248页

作者： chu yong cheng keith r.barnard wensheng zhang zhaowu zhu yoko pranolo Minerals Resources Flagship KarawaraWA 6152Australia

A number of synergistic solvent extraction （SSX） systems have been developed to recover nickel, cobalt, zinc and copper from sulphuric and chloride leach solutions by the solvent extraction team of CSIRO, Australia. These in- clude （1） Versatic 10/CLXS0 system for the separation of Ni from Ca in sulphate solutions, （2） Versatic 10/4PC system for the separation of Ni and Co from Mn/Mg/Ca in sulphate solutions, （3） Cyanex 471X/HRJ-4277 system for the separation of Zn from Cd in sulphate solutions, （4） Versatic 10/LIX63 system for the separation of Co from Mn/Mg/Ca in sulphate solutions, （5） Versatic 10/LIX63/TBP system for separation of Ni and Co from Mn/Mg/Ca in sulphate solutions, （6） Versatic 10/LIX63 system for the separation of cobalt from nickel in sulphate solutions by difference in kinetics, （7） Cyanex 272/LIX84 system for the separation of Cu/Fe/Zn from Ni/Co in sulphate solutions, （8） Versatic 10/LIX63fFBP system to recover Cu/Ni from strong chloride solutions, and [9） Versatic 10/LIX63 system to separate Cu from Fe in strong chloride solutions. The synergistic effect on metal separation and efficiency is presented and possible industrial applications are demonstrated. The chemical stability of selected SSX systems is also reported.

关键词： Synergistic solvent extraction Nickel Cobalt Copper Zinc

Rising incidence,progression and changing patterns of liver disease in Wales 1999-2019

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World Journal of Hepatology 2023年第1期15卷 89-106页

作者： Thomas peter Ignatius Pembroke Gareth John Berry Puyk keith Howkins Ruth Clarke Fidan Yousuf Marek Czajkowski Andrew Godkin Jane Salmon Andrew Yeoman Department of Gastroenterology and Hepatology University Hospital of WalesCardiff CF144XNUnited Kingdom Division of Infection and Immunity Cardiff UniversityCardiff CF144XWUnited Kingdom Digital Health and Care Wales NHS WalesCardiff CF119ADUnited Kingdom Gwent Liver Unit Royal Gwent HospitalNewport NP202UBUnited Kingdom Public Health Wales NHS WalesCardiff CF104BZUnited Kingdom

BACKGROUND Liver disease incidence and hence demand on hepatology services is *** To describe trends in incidence and natural history of liver diseases in Wales to inform effective provision of hepatology *** The registry is populated by International Classification of Diseases-10(ICD-10)code diagnoses for residents derived from mortality data and inpatient/day case activity between ***-anonymised linkage of:(1)Causative diagnoses;(2)Cirrhosis;(3)Portal hypertension;(4)Decompensation;and(5)Liver cancer diagnoses enabled tracking liver disease *** The population of Wales in 2019 was 3.1 *** 1999 and 201973054 individuals were diagnosed with a hepatic disorder,including 18633 diagnosed with cirrhosis,10965 with liver decompensation and 2316 with hepatocellular carcinoma(HCC).Over 21 years the incidence of liver diseases increased 3.6 fold,predominantly driven by a 10 fold increase in non-alcoholic fatty liver disease(NAFLD);the leading cause of liver disease from *** incidence of cirrhosis,decompensation,HCC,and allcause mortality ***-related mortality ***-related liver disease(ArLD),autoimmune liver disease and congestive hepatopathy were associated with the highest rates of decompensation and all-cause *** A 10 fold increase in NAFLD incidence is driving a 3.6 fold increase in liver disease in Wales over 21 ***-related morbidity and mortality rose more slowly reflecting the lower progression rate in *** of ArLD remained stable but was associated with the highest rates of liver-related and all-cause mortality.

关键词： Epidemiology Cirrhosis Liver failure Non-alcoholic fatty liver disease hepatitis Hepatocellular carcinoma

Ponderosa Pine Seed Source Test in Nebraska in the Central Great Plains of the United States

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Open Journal of Forestry 2013年第3期3卷 75-78页

作者： Wayne A. Geyer keith D. Lynch peter Schaefer William R. Lovette Department of Plant Science South Dakota University Vermillion USA Division of Forestry Kansas State University ManhattanUSA Nebraska Forest Service Lincoln NE 68583 Nebraska Forest Service Lincoln USA

Ponderosa pine (Pinus ponderosa Laws) has been planted widely in the Great Plains for wind breaks. A 1968 study recommended using material from south-central South Dakota and north-central Nebraska. A second test to further delineate seed sources (families) from numerous collection sites in this region was established in 1986. This paper reports results for survival, height, diameter, and D2H (diameter squared X height) measurements at 15 years. Results identify a wide range of suitable families within the region. A majority of the tested sources performed well, thus verifying the original recommendations.

关键词： Pinus ponderosa Provenance Seed Source Family Tree Selection Growth Characteristics