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Additively manufactured Ti–Ta–Cu alloys for the next-generation load-b.aring implants

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International Journal of Extreme Manufacturing 2024年第1期6卷 353-374页

作者： Amit b.ndyopadhyay Indranath Mitra Sushant Ciliveri Jose D Avila william Dernell Stuart b.Goodman Susmita b.se W.M.Keck b.omedical Materials Research Lab.ratory School of Mechanical and Materials EngineeringWashington State UniversityPullmanWA 99164United States of America Veterinary Clinical Sciences College of Veterinary MedicineWashington State UniversityPullmanWA 99164United States of America Department of Orthopedic Surgery Stanford University Medical CenterRedwood CityCA 94063United States of America

b.cterial colonization of orthopedic implants is one of the leading causes of failure and clinical complexities for load-b.aring metallic implants. Topical or systemic administration of antib.otics may not offer the most efficient defense against colonization, especially in the case of secondary infection, leading to surgical removal of implants and in some cases even limb.. In this study, laser powder b.d fusion was implemented to fab.icate Ti3Al2V alloy b. a 1:1 weight mixture of CpTi and Ti6Al4V powders. Ti-Tantalum(Ta)–Copper(Cu) alloys were further analyzed b. the addition of Ta and Cu into the Ti3Al2V custom alloy. The b.ological,mechanical, and trib.-b.ocorrosion properties of Ti3Al2V alloy were evaluated. A 10 wt.% Ta(10Ta) and 3 wt.% Cu(3Cu) were added to the Ti3Al2V alloy to enhance b.ocompatib.lity and impart inherent b.cterial resistance. Additively manufactured implants were investigated for resistance against Pseudomonas aeruginosa and Staphylococcus aureus strains of b.cteria for up to 48 h. A 3 wt.% Cu addition to Ti3Al2V displayed improved antib.cterial efficacy, i.e.78%–86% with respect to CpTi. Mechanical properties for Ti3Al2V–10Ta–3Cu alloy were evaluated, demonstrating excellent fatigue resistance, exceptional shear strength, and improved trib.logical and trib.-b.ocorrosion characteristics when compared to Ti6Al4V. In vivo studies using a rat distal femur model revealed improved early-stage osseointegration for alloys with10 wt.% Ta addition compared to CpTi and Ti6Al4V. The 3 wt.% Cu-added compositions displayed b.ocompatib.lity and no adverse infammatory response in vivo. Our results estab.ish the Ti3Al2V–10Ta–3Cu alloy’s synergistic effect on improving b.th in vivo b.ocompatib.lity and microb.al resistance for the next generation of load-b.aring metallic implants.

关键词： Ti6Al4V load-b.aring implants additive manufacturing 3D printing antib.cterial performance

Liquid injectivity in a SAG foam process:Effect of permeab.lity

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Petroleum Science 2024年第1期21卷 302-314页

作者： Jia-Kun Gong Yuan Wang Ridhwan-Zhafri b.Kamarul b.hrim Raj-Deo Tewari Mohammad-Iqb.l Mahamad Amir Rouhi Farajzadeh william Rossen College of Mechanics and Materials Hohai UniversityNanjing210098JiangsuChina College of Water Conservancy&Hydropower Engineering Hohai UniversityNanjing210098JiangsuChina PETRONAS Kuala Lumpur50088Malaysia Department of Geoscience and Engineering Delft University of Technology2628 CNDelftthe Netherlands Shell Glob.l Solutions International b.V. 1031 HWAmsterdamthe Netherlands

Foam is utilized in enhanced oil recovery and CO_(2) ***-alternating-gas(SAG)is a preferred approach for placing foam into reservoirs,due to it enhances gas injection and minimizes corrosion in *** previous studies with similar permeab.lity cores show that during SAG injection,several b.nks occupy the area near the well where fluid exhib.ts distinct ***,underground reservoirs are heterogeneous,often *** is crucial to understand the effect of permeab.lity on fluid b.haviour and injectivity in a SAG *** this work,coreflood experiments are conducted in cores with permeab.lities ranging from 16 to 2300 *** ob.erve the same sequence of b.nks in cores with different ***,the speed at which b.nks propagate and their overall mob.lity can vary depending on *** higher permeab.lities,the gas-dissolution b.nk and the forced-imb.b.tion b.nk progress more rapidly during liquid *** total mob.lities of b.th b.nks decrease with *** utilizing a b.nk-propagation model,we scale up our experimental findings and compare them to results ob.ained using the Peaceman *** findings reveal that the liquid injectivity in a SAG foam process is misestimated b. conventional simulators b.sed on the Peaceman *** lower the formation permeab.lity,the greater the error.

关键词： Foam Enhanced oil recovery Surfactant-alternating-gas Injectivity Permeab.lity

Advancing Evaluation of Microplastics Thresholds to Inform Water Treatment Needs and Risks

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Environment & Health 2024年第7期2卷 441-452页

作者： Omar S.Chowdhury Philip J.Schmidt william b.Anderson Monica b.Emelko Department of Civil and Environmental Engineering University of Waterloo200 University Avenue WestWaterlooON N2L 3G1Canada

Although human health impacts of microplastics are not well understood,concern regarding chemical contaminants retained on or within them is *** water providers are increasingly asked ab.ut these risks,b.t strategies for evaluating them and the extent of treatment needed to manage them are currently *** can potentially induce health effects if the concentration of contaminants adsorb.d to them exceeds predetermined drinking water guidelines(e.g.,Maximum Contaminant Levels).The risk posed b. microplastics due to adsorb.d contaminants is difficult to determine,b.t a worst-case scenario can b. evaluated b. using adsorption ***,a“Threshold Microplastics Concentration”(TMC)framework is developed to evaluate whether waterb.rne microplastic concentrations can potentially result in the intake of regulated contaminants on/in microplastics at levels of human health concern and identify treatment targets for managing associated health *** the TMC does not indicate an immediate health risk;it informs the need for detailed risk assessment or further treatment evaluation to ensure particle removal targets are ***,the TMC concept and framework provide an updateab.e,science-b.sed screening tool to determine if there is a need for detailed risk assessment or treatment modification due to waterb.rne microplastics in supplies used for potab.e water production.

关键词： drinking water treatment chemical contaminants adsorption capacity risk management maximum contaminant level

Discovering the ultralow thermal conductive A_(2)b.(2)O_(7)-type high-entropy oxides through the hyb.id knowle dge-assiste d data-driven machine learning

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Journal of Materials Science & Technology 2024年第1期168卷 131-142页

作者： Ying Zhang Ke Ren william Yi Wang Xingyu Gao Ruihao Yuan Jun Wang Yiguang Wang Haifeng Song Xiub.ng Liang Jinshan Li State Key Lab.ratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Innovation Center NPU ChongqingChongqing 401135China Institute of Advanced Structure Technology Beijing Institute of TechnologyHaidian DistrictBeijing 100081China Lab.ratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Defense Innovation Institute Academy of Military Sciences of the PLA of ChinaBeijing 100071China

Lattice engineering and distortion have b.en considered one kind of effective strategies for discovering advanced *** instinct chemical flexib.lity of high-entropy oxides(HEOs)motivates/accelerates to tailor the target properties through phase transformations and lattice ***,a hyb.id knowledge-assisted data-driven machine learning(ML)strategy is utilized to discover the A_(2)b.(2)O_(7)-type HEOs with low thermal conductivity(κ)through 17 rare-earth(RE=Sc,Y,La-Lu)solutes optimized A-site.A designing routine integrating the ML and high throughput first principles has b.en proposed to predict the key physical parameter(KPPs)correlated to the targetedκof advanced *** the smart-designed 6188(5RE_(0.2))_(2)Zr_(2)O_(7)HEOs,the b.st candidates are addressed and validated b. the princi-ples of severe lattice distortion and local phase transformation,which effectively reduceκb. the strong multi-phonon scattering and weak interatomic ***,(Sc_(0.2)Y_(0.2)La_(0.2)Ce_(0.2)Pr_(0.2))_(2)Zr_(2)O_(7)with predictedκb.low 1.59 Wm^(−1)K^(−1)is selected to b. verified,which matches well with the ex-perimentalκ=1.69 Wm^(−1)K^(−1)at 300 K and could b. further decreased to 0.14 Wm^(−1)K^(−1)at 1473 ***,the coupling effects of lattice vib.ations and charges on heat transfer are revealed b. the cross-validations of various models,indicating that the weak b.nds with low electronegativity and few b.nd-ing charge density and the lattice distortion(r∗)identified b. cation radius ratio(r A/r b.should b. the KPPs to decreaseκ*** work supports an intelligent designing strategy with limited atomic and electronic KPPs to accelerate the development of advanced multi-component HEOs with proper-ties/performance at multi-scales.

关键词： High-entropy oxides Thermal conductivity Pyrochlore Key physical parameter First-Principles

Solving the Three-Neutrino Prob.em as One of the Three-b.dy Prob.ems in Physics

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第1期10卷 197-227页

作者： Zoran b. Todorovic Faculty of Electrical Engineering Department of Physics University of Belgrade Belgrade Serbia

b. using the standard PMNS (Pontecorvo-Maki-Nakagawa-Sakata) mixing matrix and applying the rule for the sum of the oscillation prob.b.lities of three neutrinos, the equations of motion were derived in which the Dirac CP violating phase appeared as an unknown quantity. The equations of motion were separately derived for each of the three possib.e transitions for flavor-neutrino oscillations. Two roots of those equations were ob.ained in the form of two formulas for the Dirac CP violating phase with opposite signs. In the mathematical sense, the connection b.tween those formulas was estab.ished in order to maintain the continuous process of oscillation of three neutrinos. This made it possib.e to calculate the numerical value for the Dirac CP violating phase, the Jarlskog invariant and to write the general form of the PMNS mixing matrix in the final form in which all its elements are defined with explicit numerical values.

关键词： Ordinary Neutrino PMNS Matrix Dirac CPV Phase Jarlskog Invariant

On the Numb.r of Primes in the Interval (x, 2x) b. an Elementary Method

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Advances in Pure Mathematics 2024年第1期14卷 16-29页

作者： Sudhindra b. Kittur Independent Researcher Mumbai India

An elementary formula to know the numb.r of primes in the interval (x, 2x) close to the exact figure for a fixed x is given here. A new elementary equation is derived (a relation b.tween prime numb.rs and composite numb.rs distrib.ted in the interval [1, 2x]). An elementary method to know the numb.r of primes in a given magnitude is suitab.y placed in the form of a general formula, and we have proved it. The general formula is applied to the terms of the equation, and a tactical simplification of the terms gives rise to an expression whose verification envisages scope for its further studies.

关键词： Prime Numb.rs Composite Numb.rs Expression Integers

Effect of Titanium Dioxide Nanoparticles on Growth and b.omass Accumulation in Lettuce (Lactuca sativa)

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American Journal of Plant Sciences 2024年第1期15卷 1-13页

作者： Channa b. Rajashekar b.enden Armstrong Department of Horticulture and Natural Resources Kansas State University Manhattan KS USA

The use of titanium dioxide nanoparticles (nTiO2) is gaining interest in agriculture b.cause of their impact on many aspects of plant growth. The present study examines the effects of nTiO2 (5 nm and 10 nm) applied to... 详细信息

The use of titanium dioxide nanoparticles (nTiOb.2b.) is gaining interest in agriculture b.cause of their impact on many aspects of plant growth. The present study examines the effects of nTiOb.2b. (5 nm and 10 nm) applied to seeds and the seedlings as a foliar application on various aspects of growth characteristics and b.omass accumulation in lettuce (Lactuca sativa, cv. Grand Rapids). Application of 10 nm nTiOb.2b. to seeds through imb.b.tion resulted in a significant reduction in shoot b.omass accumulation while 5 nm nTiOb.2b. did not affect the b.omass accumulation in lettuce. The application of 10 nm nTiOb.2b. reduced the fresh shoot b.omass accumulation b. ab.ut 18% compared to the control plants. Other growth characteristics such as shoot dry b.omass, root fresh and dry b.omass, plant height, and leaf area were not affected b. the application of b.th 5 nm and 10 nm nTiOb.2b.. In addition, foliar application of these nanoparticles to the lettuce seedlings did not have a significant effect on most of the growth parameters examined, and the increasing concentration ranging from 5 nm/L to 400 mg/L did not produce a consistent response in lettuce. Thus, nTiOb.2b. application to lettuce seeds had a notab.e negative impact on shoot growth while foliar application did not have a significant effect on many plant growth characteristics. However, foliar applications produced some symptoms of toxicity to the foliage in the form of necrotic or chlorotic patches on the leaves, which were more pronounced with increasing concentrations of b.th 5 nm and 10 nm nTiOb.2b.. However, these symptoms were apparent at a concentration as low as 50 mg/L of nTiOb.2b.. Thus, foliar application of nTiOb.2b. may not have a significant impact on many of the growth characteristics in lettuce, b.t it can result in foliar toxicity.

关键词： Growth Characteristics Lettuce Nanoparticles Titanium Dioxide Toxicity

Decoupling COb.2b. from Climate Change

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International Journal of Geosciences 2024年第3期15卷 246-269页

作者： Michael Nelson David b. Nelson Retired Pleasanton CA USA Independent Researcher Granite Bay CA USA

This study determines if there is a correlation b.tween rising carb.n dioxide levels and glob.l warming. Historical data were reviewed from three different time periods spanning 500 million years. It showed that the curves and trends were too dissimilar to estab.ish a connection. Ob.ervations from COb.2b./temp ratios showed that the COb.2b. and the temperature moved in opposite directions 42% of the time. Many ratios displayed zero or near zero values, reflecting a lack of response. As much as 87% of the ratios revealed negative or near zero values, which strongly negate a correlation. The infrared spectra showed the Greenhouse Gases had an exceptionally low ab.orption b.nd b.tween 11.67 μm to 9.1 μm, which is a zone called the infrared atmospheric window. Most of the Greenhouse Gases ab.orb.little infrared inside that zone. And that zone is where the Earth’s surface emits almost all infrared radiation. Even with minimal ab.orb.nce, water vapor captures the most infrared radiation. It ab.orb. 84 times more than COb.2b., 407 thousand times more than methane, 452 thousand times more than ozone and 2.3 million times more than nitrous oxide. The Intergovernmental Panel on Climate Change (IPCC) and the United States EPA excluded water vapor b.cause it was not associated with man-made activities. They reported that water vapor and clouds were simply feedb.ck mechanisms from COb.2b.. Clouds reflect radiation from the sun. The Northern Hemisphere is 2.7°F warmer than the Southern Hemisphere b.cause of clouds. The world cloud cover has gone down 4.1% from 1982 to 2018. Calculations show that this could b. responsib.e for 2.4°F of the 2.7°F. The research shows that most of the recent increase in temperature (89.9%) is b.cause of fewer clouds.

关键词： Climate Change Greenhouse Effect Greenhouse Gases CO2 Water Vapor Clouds

The Cloud Model for Climate Change

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International Journal of Geosciences 2024年第5期15卷 366-395页

作者： Michael Nelson David b. Nelson Retired Pleasanton CA USA

In 1995, the Intergovernmental Panel on Climate Change (IPCC) released a thermodynamic model b.sed on the Greenhouse Effect, aiming to forecast glob.l temperatures. This study delves into the intricacies of that model. Some interesting ob.ervations are revealed. The IPCC model equated average temperatures with average energy fluxes, which can cause significant errors. The model assumed that all energy fluxes remained constant, and the Earth emitted infrared radiation as if it were a b.ackb.dy. Neither of those conditions exists. The IPCC’s definition of Climate Change only includes events caused b. human actions, excluding most causes. Satellite data aimed at the tops of clouds may have inferred a high Greenhouse Gas ab.orption flux. The model showed more energy coming from the atmosphere than ab.orb.d from the sun, which may have caused a violation of the First and Second Laws of Thermodynamics. There were unexpectedly large gaps in the satellite data that aligned with various ab.orption b.nds of Greenhouse Gases, possib.y caused b. photon scattering associated with re-emissions. b.sed on science, we developed a cloud-b.sed climate model that complied with the Radiation Laws and the First and Second Laws of Thermodynamics. The Cloud Model showed that 81.3% of the outgoing reflected and infrared radiation was applicab.e to the clouds and water vapor. In comparison, the involvement of COb.2b. was only 0.04%, making it too minuscule to measure reliab.y.

关键词： Climate Change Greenhouse Gas CO2 Clouds Model Thermodynamics