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Correcting distortions of thin-walled machined parts by machine hammer peening

Chinese Journal of Aeronautics 2024年第6期37卷 439-453页

作者： Aitor MADARIAGA Mikel CUESTA Gorka ORTIZ-DE-ZARATE Eneko SAENZ-DE-ARGANDONA Denis SORIANO Michael B.PRIME pedro jose ARRAZOLA Department of Materials University of ManchesterOxford RoadManchester M139PLUnited Kingdom Mechanical and Industrial Production Department Faculty of EngineeringMondragon UnibertsitateaArrasate 20500Spain Los Alamos National Laboratory Los AlamosNew MexicoUSA

Thin-walled aerostructural components frequently get distorted after the machining *** to correct distortions or eventually rejecting parts significantly increases the *** paper proposes a new approach to correct distortions in thin-walled components by strategically applying hammer peening on target surfaces of a machined *** alloy 7475-T7351 was chosen for this *** study was divided in two ***,the residual stresses(RS)induced by four different pneumatic hammer peening conditions(modifying the stepover distance and initial offset)were characterised in a test coupon,and one of the conditions was selected for the next *** the second stage,a FEM model was used to predict distortions caused by machining in a representative ***,the RS induced by hammer peening were included in an FEM model to define two hammer peening strategies(varying the coverage area)to analyse the capability to reduce *** workpieces were machined and then treated with the simulated hammer peening strategies for experimental *** in the test coupon showed that pneumatic hammer peening can generate high compressive RS(-50 to350 MPa)up to 800 lm depth,with their magnitude increasing with a reduced stepover *** of hammer peening over 4% of the surface of the representative workpiece reduced the machininginduced distortions by 37%,and a coverage area of 100% led to and overcorrection by a factor of *** confirms that hammer peening can be strategically applied(in target areas and changing the percentage of coverage)to correct low or severe distortions.

关键词： Aeronautics Machining,Hammer Peening Aluminium alloy Distortions Residual Stress

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Unveiling Plant mTERF Functions

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Molecular Plant 2012年第2期5卷 294-296页

作者： pedro Robles jose Luis Micol Victor Quesada Instituto de Bioingenieria Universidad Miguel Hernandez Campus de Elche 03202 Elche Spain

Chloroplasts and mitochondria genomes contain a few dozen genes required for gene expression, photosynthesis, and the electron transport chain. However, proteomic and bioinformatic studies suggest that approximately 2000 and 2600 proteins are located in plant mitochondria and chloroplasts, respectively; most of them are encoded by nuclear genes, synthesized in the cytoplasm, and targeted to organelles. Despite the simplicity of organelle genomes, their transcriptional regulation is complex and can only be partially explained by currently known transcriptional machinery components, suggesting that additional unidentified regulatory factors exist （Liere et al., 2011）.

关键词： Unveiling Plant

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Improving surface integrity when drilling CFRPs and Ti-6Al-4V using sustainable lubricated liquid carbon dioxide

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Chinese Journal of Aeronautics 2023年第7期36卷 129-146页

作者： In˜igo RODRIGUEZ pedro jose´ARRAZOLA Mikel CUESTA Luka STERLE Franci PUSˇAVEC Faculty of Engineering Mondragon UnibertsitateaArrasate-Mondragon 20500Spain Faculty of Mechanical Engineering University of LjubljanaLjubljana 1000Slovenia

In the quest for decreasing fuel consumption and resulting gas emissions in the aeronautic sector,lightweight materials such as Carbon Fiber Reinforced Polymers(CFRPs)and Ti-6Al-4V alloys are being *** materials,with excellent weight-to-strength ratios,are widely used for structural applications in aircraft *** date,several studies have been published showing that the use of metalworking fluids(MWFs),special tool geometries,or advanced machining techniques is required to ensure a surface quality that meets aerospace component *** MWFs pose a number of environmental and worker health hazards and also degrade the mechanical properties of CFRPs due to water absorption in the ***,a transition to more environmentally friendly cooling/lubrication techniques that prevent moisture problems in the composite is *** research shows that lubricated LCO_(2) is a viable option to improve the quality of drilled CFRP and titanium aerospace components compared to dry machining,while maintaining clean work *** results show that the best combination of tool geometry and cooling conditions for machining both materials is drilling with Brad point drills and lubricated LCO_(2).Drilling under these conditions resulted in a 90%improvement in fiber pullout volume compared to dry machined CFRP *** addition,a 33% reduction in burr height and a 15% improvement in surface roughness were observed compared to dry drilling of titanium.

关键词： Carbon fibers Cryogenics Green manufacturing Machining Solid lubricants Surface morphology Titanium alloys

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Performance Parameters:Demobilization Antibiotic Resistant Bacteria(ARB)and Carrying Genes(ARG)in Wastewater Disinfection

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Journal of Environmental Science and Engineering(B) 2024年第1期13卷 1-8页

作者： Solange Kazue Utimura Denise Crocce Romano Espinosa Marcio Luís Busi da Silva Elisabete de Santis Braga pedro jose Alvarez Department of Chemical Engineering USPR.do LagoSão Paulo 25005508-080Brazil Department of Physical Chemical and Geological OceanographyUSPPraça do Oceanográfico 191SPBrazil Department of Civil and Environmental Engineering Rice University6100 Main St.HoustonTexas 77005USA

The UV irradiation is used for removing Antibiotic Resistant Bacteria(ARB)and Antibiotic Resistance Genes(ARG)from wastewater *** are viruses that infect within bacteria,are recognized for bacterial *** influence of some parameters in quantification and performance influencing of pathogen demobilization could be considered in disinfection of *** comparison of Polyvalent phage(NE1)versus Coliphage(NE4)in suppressing a bacterium Escherichia coli(NDM-1:b-lactam-resistant)with UV irradiation was observed the efficacy in reduction of cells in the disinfection and parameter *** results with the effect of UV-C irradiation on NDM-1 infected with 1%of NE4 showed a decrease of cells from 8×10^(6)to 2×10^(5)in 60 min with UV-C *** NDM1(***)was infected with 1%of NE4(Polyvalent Phage)under magnetic stirring for 1 h,the cells count was 8×10^(6).After 1 h in UV-C e×posure,the cells number reached 3×10^(5).The NDM1 that was e×posed in 1 h of UV-C irradiation and then was infected with 1%of *** counting were done 24 h after this *** cells were e×posed in UV-C and showed a reduction in the number of cells from 1×10^(8)to 4×10^(5)after 60 *** results indicate that bacteriophages can mitigate bacteria species,and combined the conventional water disinfection technologies that can support the microbial safety control strategies.

关键词： Antibiotic Resistant Bacteria(ARB) Antibiotic Resistance Genes(ARG) wastewater treatment disinfection Escherichia coli(E.coli).

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What is the most effective exercise protocol to improve cardiovascular fitness in overweight and obese subjects？

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Journal of Sport and Health Science 2017年第4期6卷 454-461页

作者： Eliane Aparecida Castro Ana Belen Peinado pedro jose Benito MercedeS Galindo Marcela Gonzalez-Gross Rocio Cupeiro Department of Health and Human Performance Faculty of Physical Activity and Sport Sciences Universidad Polit~cnica de Madrid Madrid 28040 Spain LFE Research Group Universidad PolitOcnica de Madrid Madrid 28040 Spain Faculty of Physical Activity and Sport Sciences Universidad Politecnica de Madrid Madrid 28040 Spain ImFINE Research Group Universidad PolitOcnica de Madrid Madrid 28040 Spain

Background: Increased peak oxygen consumption(VO2 peak) can reduce cardiovascular risks associated with obesity. Our aim was to analyze the effect of a weight loss program on cardiovascular fitness in overweight(W) and obese(O) ***: One hundred and sixty-seven subjects(77 males and 90 females), aged 18–50 years, performed a modified Bruce protocol before(pre)and after(post) a weight loss program of 24 weeks. This program combined physical training(strength, S; endurance, E; combined strength + endurance, SE; or physical activity recommendation, PA) 3 times per week, with a 25%–30% caloric restriction ***: VO2 peak improved in overweight and obese males(pre and post values in L/min, respectively; W = 3.2 ± 0.6 vs. 3.7 ± 0.5, p < 0.001;O = 3.6 ± 0.6 vs. 3.8 ± 0.6, p = 0.013) as well as in overweight females(2.0 ± 0.3 vs. 2.3 ± 0.4, p < 0.001). VO2 peak in the first ventilatory threshold(VT1) increased for all 4 interventions in males(p < 0.05), except for S in the obese group(1.6 ± 0.2 vs. 1.7 ± 0.3, p = 0.141). In females, it increased in E(0.9 ± 0.2 vs. 1.4 ± 0.3, p < 0.001), SE(0.9 ± 0.2 vs. 1.2 ± 0.4, p = 0.003), and PA(0.9 ± 0.1 vs. 1.2 ± 0.2, p = 0.006) in overweight groups. Time-to-exhaustion improved in all subjects except for females in PA group(15.7 ± 0.3 min vs. 15.9 ± 0.3 min, p = 0.495).Conclusion: Our results suggest that all methods, including the recommendation of physical activity, can improve cardiovascular fitness in overweight subjects and obese males.

关键词： Combined training Endurance training Obesity Oxygen consumption Physical activity Strength training Ventilatory threshold

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Forest fire risk indices and zoning of hazardous areas in Sorocaba,Sao Paulo state,Brazil

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Journal of Forestry Research 2020年第2期31卷 581-590页

作者： Leonardo Guimaraes Ziccardi Claudio Roberto Thiersch Aurora Miho Yanai Philip Martin Fearnside pedro jose Ferreira-Filho Department of Environmental Dynamics National Institute for Research in Amazonia(INPA)Av.Andre AraujoNo.2936ManausAmazonasCEP 69067-375Brazil Department of Environmental Sciences Federal University of Sao Carlos(UFSCar)SorocabaSao PauloCEP 18052-780Brazil

This study compares the performance of three fire risk indices for accuracy in predicting fires in semideciduous forest fragments,creates a fire risk map by integrating historical fire occurrences in a probabilistic density surface using the Kernel density estimator(KDE)in the municipality of Sorocaba,Sao Paulo state,*** logarithmic Telicyn index,Monte Alegre formula(MAF)and enhanced Monte Alegre formula(MAF+)were employed using data for the period 1 January 2005 to 31 December *** data and numbers of fire occurrences were obtained from the National Institute of Meteorology(INMET)and the Institute for Space Research(INPE),*** performance measures were calculated:Heidke skill score(SS)and success rate(SR).The MAF+index was the most accurate,with values of SS and SR of 0.611%and 62.8%,*** fire risk map revealed two most susceptible areas with high(63 km^2)and very high(47 km^2)risk of fires in the *** of the best risk index and the generation of fire risk maps can contribute to better planning and cost reduction in preventing and fighting forest fires.

关键词： Forest fire risk maps Forest fire protection Monitoring Monte Alegre formula

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Theoretical and Experimental Analysis of Vortex Origin

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Journal of Mathematics and System Science 2013年第5期3卷 251-261页

作者： pedro Guido Aldana jose Roberto Mercado Mexican Institute of Water Technology Paseo Cuauhn6huac 8532 Progreso Jiutepec Morelos CP 62550 Mexico

Several investigations refer to the issue of creation and identification of vortices in flows with different regime and presence of obstacles. Reasons have to do with the crucial role that vortices play in nature and industrial processes （sediment transport, mixing, radiation, noise, etc.）. Despite the contributions, further work is needed in order to perform more analysis of the mathematical arguments used to explain this phenomenon. In this idea order, the paper presents some advances in mathematical analysis and experimental results. In the first section, we do a description of the fluid motion from a fractional view through a sequence of three steps： Darcy＇s law, Navier-Stokes equations and Reynolds equations. Next, a representation of the temporal change of kinetic energy is found, which allows the possibility of the two signs. We obtain a description of the process of vortex creation. A length that represents the transition between flow and vortex intensity is found; then a succession of lengths is established that allows scaling from micro to macro. In the second section, experimental results are present; we consider vortex creation and its detection upstream of a bed form similar to that found in rivers, installed in an open channel, equipped with a water circulation system. For vortex detection, a methodology based on the particle image velocimetry PIV technique is proposed. So, we fulfill two objectives： vortex identification and its passage frequencies behind the bed form installed in the channel. Such procedure allows a computer process time reduction in vortices identification task.

关键词： Navier-Stokes fractional equation Darcy's law vortex detection particle image velocimetry open channel bed form.

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Effect of a Single Shot Sciatic Nerve Block Combined with a Continuous Femoral Block on Pain Scores After Knee Arthroplasty.A Randomized Controlled Trial

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Open Journal of Anesthesiology 2012年第4期2卷 107-112页

作者： Raul Carvalho Luisa Calixto jose pedro Braganca Servico de Anestesia Centro Hospitalar do PortoPortoPortugal Departamento de Ciencias da Informacao e da Decisao em Saude Faculdade de MedicinaUniversidade do PortoPortoPortugal

Background and Purpose: Postoperative pain after knee arthroplasty (TKA) is reported as severe in up to 60% of patients. Continuous femoral nerve blocks (CFNB) are a choice for major knee repair, but controversies remain about the need of supplemental sciatic nerve blocks (SNB) for better analgesia. Our aim is to assess the effect of the association of a SNB to a CFNB to reduce postoperative pain after TKA. Methods: A prospective randomized, single blinded, controlled study, on 50 patients undergoing TKA. Control group received a CFNB before general anesthesia;in the intervention group a single shot SNB was added after the CFNB was done. After the end of surgery all patients started a continuous local anesthetic infusion through the femoral catheter in the PACU (post-anesthesia care unit). Pain scores were measured in the PACU and at 12 h and 24 h postoperative using a visual analog scale (VAS). Results: VAS pain scores (mm) were lower and statistically significant for the intervention group up to 12 h postoperative: PACU admission mean VAS = 59.4 vs 30.2, P = 0.001;at 12 h mean VASr = 26.1 vs 9.2, P = 0.006;at 24 h mean VASr = 30.1 vs 32.7, P = 0.723. Conclusions: The association of a single shot SNB with a CFNB significantly reduces postoperative pain scores after TKA up to 12 h. At 24 h there are no differences between groups.

关键词： Postoperative Pain Knee Arthroplasty Regional Anesthesia Nerve Blocks

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CONSTANS alters the circadian clock in Arabidopsis thaliana

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Molecular Plant 2024年第8期17卷 1204-1220页

作者： pedro de los Reyes Gloria Serrano-Bueno Francisco J.Romero-Campero He Gao jose M.Romero Federico Valverde Plant Development Group-Institute for Plant Biochemistry and Photosynthesis Consejo Superior de Investigaciones CientificasUniversidad de SevillaSevilleSpain Department of Computer Science and Artificial Intelligence Universidad de SevillaSevilleSpain Department of Plant Developmental Biology Max Planck Institute for Plant Breeding ResearchCologneGermany Department of Plant Biochemistry and Molecular Biology Universidad de SevillaSevilleSpain

Plants are sessile organisms that have acquired highly plastic developmental strategies to adapt to the *** these processes,the floral transition is essential to ensure reproductive success and is finelyregulated by several internal andexternal genetic *** photoperiodic pathway,which controls plant response to day length,is one of the most important pathways controlling *** Arabidopsis photoperiodic flowering,CONSTANS(CO)is the central gene activating the expression of the florigen FLOWERING LOCUS T(FT)in the leaves at the end of a long *** circadian clock strongly regulates Co ***,to date,no evidence has been reported regarding a feedbackloop from the photoperiod pathway back to the circadian *** transcriptional networks,we have identified relevant network motifs regulating the interplay between the circadian clock and the photoperiod *** expression,chromatin immunoprecipitation experiments,and phenotypic analysis allowed us to elucidate the role of Co over the circadian *** with altered cO expression showed a different internal clock period,measured by daily leaf rhythmic *** showed that co upregulates the expression of key genes related to the circadian clock,such as CCA1,LHY,PRR5,and Gl,at the end of a long day by bindingto specific sites on their ***,a high numberof PRR5-repressed target genes are upregulated by CO,and this could explain the phase transition promoted by *** CO-PRR5 complex interacts with the bZiP transcriptionfactor HY5andhelps to localize the complex in the promoters of clock *** together,our results indicate that there may be a feedback loop in which co communicates back to the circadian clock,providing seasonal information to the circadian system.

关键词： CONSTANS circadian clock photoperiod

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Multivariate Statistical Analysis of Phyllite Samples Based on Chemical(XRF)and Mineralogical Data by XRD

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American Journal of Analytical Chemistry 2012年第5期3卷 347-363页

作者： Eduardo Garzon Garzon Antonio Ruiz-Conde pedro jose Sanchez-Soto Department of Rural Engineering University of AlmeriaLa Canada de San UrbanoSpain Instituto de Ciencia de Materiales Centro Mixto C.S.I.C.—US.Avda.Americo VespuccioSevillaSpain

It is presented the results obtained of a multivariate statistical analysis concerning the chemical and phase composition, as a characterization purpose, carried out with 52 rock phyllite samples selected from the provinces of Almería and Granada (SE Spain). Chemical analysis was performed by X-ray fluorescence (XRF). Crystalline phase analysis was performed by X-ray powder diffraction (XRD) and the mineralogical composition was then deduced. Quantification of weight loss (100? and 1000?C) was carried out by thermal analysis. The aims of this investigation were to analyze and compare the chemical and mineralogical composition of all these samples and to find similarities and differences between them to allow a classification. Several correlations between results of the characterization techniques have been also investigated. All the data have been processed using the multivariate statistical analysis method. The XRF macro-elements (10) and microelements (39) data generate one macrogroup with two new subgroups (1 and 2), and an isolated sample. In subgroup 1 of macroelements, a positive correlation was found between XRF results and geographic location characterized by lower MgO content, which is associated to its geological origins. When multivariate statistical analysis is applied to results obtained by XRD, two groups appear: the first one with a sample with zero percentage of iron oxide and the second one with the rest of the samples, which is classified in two groups. A correlation is observed between the alkaline content (XRF) and illite (XRD), CaO and MgO with dolomite and indirectly between the weight loss after heating at 1000?C and the contents of phase minerals that lose structural water (illite + chlorite) or carbon dioxide (dolomite). The present investigation has interest and implications for geochemistry and analytical chemistry concerning earth rocks and silicate raw materials.

关键词： Selection Multivariate Phyllites XRF XRD

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