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Analysis of synthetic parameters for coating aluminum powders with phenyltriethoxysilane coupling agent and their effects on powder flow behavior

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Particuology 2024年第7期90卷 412-417页

作者： Lillian M.Mawby Bellamarie Ludwig Benjamin J.Lear Department of Chemistry The Pennsylvania State UniversityUniversity ParkPA16802USA Applied Research Laboratory The Pennsylvania State UniversityUniversity ParkPA16802USA

Though silanization of aluminum powder is currently used to improve its flow properties,for use as an alternative fuel source,there are a wide range of experimental parameters for the process and not all of them have been thoroughly *** this is complete,it is unknown if the process is optimized in terms of time,efficiency,and ***,we report on a study into the effects of changes in humidity,degree of agitation,reaction temperature,and curing time upon the deposition of phenyl triethoxysilane into 20μm(d50)aluminum *** confirm the deposition of the coating via diffuse reflectance infrared spectroscopy and x-ray photoelectron *** then characterize the coated particles using apparent density measurements and Carney flow *** analysis of variance,we find that,of the parameters explored,only changes in cure time and reaction temperature provide meaningful changes to the apparent density,while none of our parameters produced statistically significant changes in Carney flow ***,we conclude that,when optimizing silanization of aluminum particles,environmental control of humidity is unneeded and that the reaction can be run with minimal *** ability to largely ignore these parameters is a benefit to large-scale processing.

关键词： Aluminum powder Silane Fluidization Apparent density Carney flow

Circulation Pattern Controls of Summer Temperature Anomalies in Southern Africa

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Advances in Atmospheric Sciences 2024年第2期41卷 341-354页

作者： Chibuike Chiedozie IBEBUCHI Cameron C.LEE Department of Geography Kent State UniversityKentOhio 44242USA ClimRISE Lab Kent State UniversityKentOhio 44242USA

This study investigates the relationship between circulation patterns and austral summer temperature anomalies in southern Africa. The results show that the formation of continental lows tends to increase the thickness of the lower atmosphere. Further, the distinct variabilities of high and low pressure under the circulation types, influence air mass advection from the adjacent oceans, as well as atmospheric stability over land. Stronger anticyclonic circulation at the western branch of the Mascarene high-pressure system enhances the low-level cold air advection by southeast winds,decreases the thickness, and lowers the temperature over a majority of the land in southern Africa. Conversely, a weaker Mascarene High, coupled with enhanced cyclonic activity in the southwest Indian Ocean increases low-level warm air advection and increases temperature anomalies over vast regions in southern Africa. The ridging of a closed South Atlantic anticyclone at the southern coast of southern Africa results in colder temperatures near the tip of southern Africa due to enhanced low-level cold air advection by southeast winds. However, when the ridge is weak and westerly winds dominate the southern coast of southern Africa, these areas experience temperature increases. The northward track of the Southern Hemisphere mid-latitude cyclone, which can be linked to the negative Southern Annular Mode, reduces the temperature in the southwestern part of southern Africa. Also, during the analysis period, El Ni?o was associated with temperature increases over the central parts of southern Africa;while the positive Indian Ocean dipole was linked to a temperature increase over the northeastern, northwestern, and southwestern parts of southern Africa.

关键词： temperature circulation types Subtropical Indian Ocean dipole Southern Annular Mode El Ni?o Indian Ocean dipole Mascarene High South Atlantic anticyclone

Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 319-329页

作者： Jay Kumar Shah Hao Wang Said El-Hawwat Centre of Advanced Infrastructure and Transportation RutgersThe State University of New JerseyNJ 08854USA Department of Civil and Environmental Engineering RutgersThe State University of New JerseyNJ 08854USA

Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively *** growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance *** study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE *** experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch *** dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack *** findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth.

关键词： polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling

Highlights in recent wireless power IC research

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Journal of Semiconductors 2024年第4期45卷 5-7页

作者： Cheng Huang Junyao Tang Iowa state university AmesIowa50011USA

Wireless power transfer(WPT)has been a popular topic in power integrated circuit(IC)designs in the past *** slogan"cutting the last wire"presented in ISSCC’15[1],WPT is poised to take over many wired power deliveries applica-tions today,just like what happened to wireless communica-tion *** the years,WPT has become more mature and more wirelessly charged or powered products have become available on the *** mini review intends to summarize recent breakthroughs in WPT inte-grated circuits(IC)research.

关键词： WPT power wireless

Extreme Weather Disruptions and Emergency Preparedness Among Older Adults in Ohio: An Eight-County Assessment

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International Journal of Disaster Risk Science 2024年第2期15卷 213-225页

作者： Smitha Rao Fiona C.Doherty Anthony Traver Marisa Sheldon Emma Sakulich Holly Dabelko‑Schoeny College of Social Work The Ohio State UniversityColumbusOH 43210USA Age Friendly Innovation Center College of Social WorkThe Ohio State UniversityColumbusOH 43210USA College of Public Health The Ohio State UniversityColumbusOH 43210USA

The disproportionate risks and impacts of climate change and extreme weather on older adults are increasingly evident. While especially true in disaster-prone areas, human-caused climate change introduces an element of uncertainty even in previously identified “safe” regions such as the Midwestern United states. Using a cumulative disadvantage and vulnerability-informed framework and descriptive statistics from multiple data sources, this article provides an overview of climate impacts, vulnerabilities, and county-level characteristics, focusing on older adults living in Central Ohio. A comparative multiple-case study methodology was used to triangulate regionally representative primary and secondary data sources to examine state and county-level measures of vulnerability, emergency preparedness, and disruptions caused by extreme weather among older adults across eight counties in Central Ohio. Seventy-eight percent of older adults in the sample reported being prepared for emergencies per Federal Emergency Management Agency guidelines. Older adults in Union County reported the highest rates of preparedness, while those in Fayette County reported the lowest. County-level rates of disruption of life activities by extreme weather ranged widely. Among the most rural in the region, Fayette County emerged as uniquely disadvantaged, with the lowest median income, the most vulnerable across multiple social vulnerability dimensions, and the most reported disruptions to life activities from extreme weather. County profiles offer a snapshot of existing vulnerabilities, socioeconomic conditions, special needs, preparedness, and current disruptions among older adults in the region and can inform resource mobilization across community and policy contexts.

关键词： Disaster preparedness Extreme weather Midwestern United states Older adults Regional assessment Social vulnerability

Investigation of HCAR2 antagonists as a potential strategy to modulate bovine leukocytes

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1567-1577页

作者： Laman K.Mamedova Kirby C.Krogstad Paiton O.McDonald Laxman Pokhrel Duy H.Hua Evan C.Titgemeyer Barry J.Bradford Department of Animal Science Michigan State UniversityEast LansingMichigan 48824USA Department of Animal Sciences and Industry Kansas State UniversityManhattanKS 66506USA Comparative Medicine and Integrative Biology East LansingMI 48824USA Department of Chemistry Kansas State UniversityManhattanKS 66506USA

Background Dairy cows experiencing ketosis after calving suffer greater disease incidence and are at greater risk of leaving the herd. In vitro administration of beta-hydroxybutyric acid(BHBA;the primary blood ketone) has inhibitory effects on the function of bovine leukocytes. BHBA is a ligand of HCAR2 and the activation of these receptors promotes an anti-inflammatory response which may be related with immunosuppression observed in transition dairy cattle. The objective of this study was to identify and test antagonists for HCAR2 in bovine immune cells cultured with *** We observed expression of HCAR2 at the protein level within lymphocytes, monocytes, and granulocytes. The proportion of cells expressing HCAR2 tended to be greater in mid-lactation compared to early lactation cows;the increase was a result of increased proportion of T and B cells expressing HCAR2. Stimulation of HCAR2 with niacin or BHBA promoted Ca^(2+) mobilization in neutrophils and mononuclear cells. Mononuclear cells treated with BHBA had diminished intracellular Ca^(2+) responses when HCAR2 was knocked down by si RNA silencing, indicating Ca^(2+) mobilization was mediated by HCAR2 signaling. Two candidate antagonists for HCAR2, synthesized from niacin(NA-1 and NA-5), were tested;monocytes and neutrophils pre-treated with NA-1 and NA-5 had reduced Ca^(2+) mobilization after incubation with BHBA. Furthermore, NA-5 but not NA-1 prevented BHBA-associated reductions in cyclic *** We demonstrated that HCAR2 is present on bovine leukocytes and has greater expression later in lactation. We confirmed that BHBA and niacin derived HCAR2 antagonists alter bovine leukocyte activity. Our results demonstrate that both BHBA and niacin affect bovine leukocyte Ca^(2+) mobilization in a HCAR2-dependent manner.

关键词： Flow cytometry GPR109A HM74A Ketosis

Anderson Acceleration of Gradient Methods with Energy for Optimization Problems

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1299-1318页

作者： Hailiang Liu Jia-Hao He Xuping Tian Department of Mathematics Iowa State UniversityAmesIAUSA Department of Agricultural and Biosystems Engineering Iowa State UniversityAmesIAUSA

Anderson acceleration(AA)is an extrapolation technique designed to speed up fixed-point *** optimization problems,we propose a novel algorithm by combining the AA with the energy adaptive gradient method(AEGD)[arXiv:2010.05109].The feasibility of our algorithm is ensured in light of the convergence theory for AEGD,though it is not a fixed-point *** provide rigorous convergence rates of AA for gradient descent(GD)by an acceleration factor of the gain at each implementation of *** experimental results show that the proposed AA-AEGD algorithm requires little tuning of hyperparameters and exhibits superior fast convergence.

关键词： Anderson acceleration(AA) Gradient descent(GD) Energy stability

Limited impacts of occasional tillage on dry aggregate size distribution and soil carbon and nitrogen fractions in semi-arid drylands

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International Soil and Water Conservation Research 2024年第1期12卷 96-106页

作者： Wooiklee S.Paye Vesh R.Thapa Rajan Ghimire New Mexico state university Agricultural Science CenterClovisNM88101USA New Mexico state university Department of Plant and Environmental SciencesLas CrucesNM88003USA

Tillage management that minimizes the frequency and intensity of soil disturbance can increase soil carbon(C)and nitrogen(N)sequestration and improve the resilience of dryland cropping systems,yet the impact of occasional disturbance on soil aggregate formation and the soil organic carbon(SOC)storage within aggregates has not been studied *** evaluated the effect of four tillage management practices on soil dry aggregate size distribution,aggregate-protected C and N,mineral-associated organic matter carbon(MAOM-C),particulate organic matter carbon(POM-C),and corn(Zea mays L.)and sorghum(Sorghum bicolor(L.)Moench)yields in a semi-arid dryland cropping *** included conventional tillage(CT),strip-tillage(ST),no-tillage(NT),and occasional tillage(OT)management in a corn-sorghum *** macro-aggregates were 51-54%greater under ST,NT,and OT,while small and micro-aggregates were greater in *** tillage reduced soil aggregate-associated C by 28-31%in macro-aggregates and 47-53%in small aggregates at 26 months(M)sampling compared to ST,NT,and *** clay+silt fraction,CT had 14-16%,21-26%,and 36-43%less SOC at 7,14,and 26M samplings,respectively,than ST,NT,and *** associated N was generally similar under ST,NT,and OT,which was greater on average than *** MOAM-C and POM-C under ST,NT,and OT were generally greater than respective SOC fractions under CT at 19 and 26 M after OT *** and sorghum yields were similar among tillage systems in 2020,but greater under ST,NT,and OT than CT in *** results suggest that while frequent intensive tillage can lower SOC and N storage,a single stubble mulch occasional tillage after several years of NT does not lead to soil C and N losses and soil structural instability in semi-arid drylands.

关键词： Conventional tillage Occasional tillage Aggregate associated carbon Mineral associated organic matter carbon(MAOM-C) Particulate organic matter carbon(POM-C)

Two intestinal microbiota-derived metabolites, deoxycholic acid and butyrate, synergize to enhance host defense peptide synthesis and alleviate necrotic enteritis

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1158-1172页

作者： Dohyung M.Kim Jing Liu Melanie A.Whitmore Isabel Tobin Zijun Zhao Guolong Zhang Department of Animal and Food Sciences Oklahoma State UniversityStillwaterOKUSA

Background Necrotic enteritis(NE)is a major enteric disease in poultry,yet effective mitigation strategies remain *** acid(DCA)and butyrate,two major metabolites derived from the intestinal microbiota,have independently been shown to induce host defense peptide(HDP)***,the potential synergy between these two compounds remains *** To investigate the possible synergistic effect between DCA and butyrate in regulating HDP synthesis and barrier function,we treated chicken HD11 macrophage cells and jejunal explants with DCA and sodium butyrate(NaB),either individually or in combination,for 24 ***,we performed RNA isolation and reverse transcrip-tion-quantitative PCR to analyze HDP genes as well as the major genes associated with barrier *** further determine the synergy between DCA and NaB in enhancing NE resistance,we conducted two independent trials with Cobb broiler *** each trial,the diet was supplemented with DCA or NaB on the day-of-hatch,followed by NE induction through sequential challenges with Eimeria maxima and Clostridium perfringens on d 10 and 14,*** recorded animal mortality after infection and assessed intestinal lesions on d *** impact of DCA and NaB on the microbiota in the ileum and cecum was evaluated through bacterial 16S rRNA gene *** We found that the combination of DCA and NaB synergistically induced multiple HDP genes in both chicken HD11 cells and jejunal ***,the gene for claudin-1,a major tight junction protein,also exhibited synergistic induction in response to DCA and ***,dietary supplementation with a combination of 0.75 g/kg DCA and 1 g/kg NaB led to a significant improvement in animal survival and a reduction in intestinal lesions compared to either compound alone in a chicken model of ***,the cecal microbiota of NE-infected chickens showed a marked decrease in SCFA-producing bacteria such as Bacteroides,F

关键词： Bile acids Host defense peptides Metabolites Microbiome Necrotic enteritis Short-chain fatty acids