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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 160-166页

作者： A Visagan P Ganesh department of production Technology Madras Institute of TechnologyChennai-600044India

We investigated the parametric optimization on incremental sheet forming of stainless steel using Grey Relational Analysis(GRA) coupled with Principal Component Analysis(PCA). AISI 316L stainless steel sheets were used to develop double wall angle pyramid with aid of tungsten carbide tool. GRA coupled with PCA was used to plan the experiment conditions. Control factors such as Tool Diameter(TD), Step Depth(SD), Bottom Wall Angle(BWA), Feed Rate(FR) and Spindle Speed(SS) on Top Wall Angle(TWA) and Top Wall Angle Surface Roughness(TWASR) have been studied. Wall angle increases with increasing tool diameter due to large contact area between tool and workpiece. As the step depth, feed rate and spindle speed increase,TWASR decreases with increasing tool diameter. As the step depth increasing, the hydrostatic stress is raised causing severe cracks in the deformed surface. Hence it was concluded that the proposed hybrid method was suitable for optimizing the factors and response.

关键词： single point incremental forming AISI 316L taguchi grey relation analysis principal component analysis surface roughness scanning electron microscopy

超声功率对冷却斜槽模压A356合金液相分数、微观组织及物理特性的影响

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Journal of Central South University 2022年第4期29卷 1098-1106页

作者： Pabak MOHAPATRA Nirmal Kumar KUND department of production Engineering VSS University of TechnologyBurla 768018India

本文采用超声振动冷却斜槽对A356合金进行成型。超声振动冷却斜槽能剪切产生半固态铸造/热处理坯料的浆料,研究了5种不同的超声功率(0、75、150、200、250 W)下坯料的液相分数、显微组织、物理特性。当超声功率为150 W时,合金的微观组... 详细信息

本文采用超声振动冷却斜槽对A356合金进行成型。超声振动冷却斜槽能剪切产生半固态铸造/热处理坯料的浆料,研究了5种不同的超声功率(0、75、150、200、250 W)下坯料的液相分数、显微组织、物理特性。当超声功率为150 W时,合金的微观组织更精细、圆整,物理特性更强。由于晶粒细化和晶界/Hall-Petch强化导致微观结构改变,从而导致物理性能改变。晶粒尺寸越小,强度/形状因子越高;晶粒均匀性越高,塑性越好。由于温度均匀化的合并作用,再加热改善了合金的微观组织;随着孔隙度的降低和溶解的增强以及均匀性的增强,在再加热过程中材料的物理性能得到改善。

关键词：超声波功率微观结构物理性能半固体铸造 A356合金冷却斜槽

Involvement of Quebracho tannins in diet alters productive and reproductive efficiency of postpartum buffalo cows

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Animal Nutrition 2019年第1期5卷 80-86页

作者： Sobhy M.A.Sallam Marwa F.A.Attia Adel N.M.Nour El-Din Samir Z.El-Zarkouny Adel M.Saber Hani M.El-Zaiat Moustafa M.Zeitoun department of Animal and Fish production Faculty of AgricultureAlexandria University Animal production Research Institute Agricultural Research CenterDokki

This study was conducted to investigate the effects of 10 weeks supplementation of Quebracho tannins(QT; 0 [control], 100 [QT100] or 200 g/[cow$d] [QT_(200)]) to 30 multiparous postpartum buffalo cows(10 cows per group) on milk yield and composition, blood metabolites and reproductive performance.Supplementation of QT100 had no significant effect on milk yield, whereas QT_(200) decreased(P < 0.05) this trait. Compared with the control group, both QT levels decreased(P < 0.05) fat-corrected milk(FCM)yield, but no significant effects were found on percentages of milk fat and protein. Contrariwise, yields of milk fat, lactose and milk protein were decreased(P < 0.05) when QT_(200) was supplemented. The solids nonfat(SNF) percentage and yield were decreased(P < 0.05) with QT100 supplementation. Moreover, QT tended to numerically reduce total number of ovarian follicles, number of small follicles, peripheral progesterone concentration and conception rate. Supplementation of QT_(200) numerically increased number of large follicles, mean diameter of large follicle, number and diameters of corpora lutea. The inclusion of QT_(200) shortened days open(DO) and decreased number of services per conception.Contrariwise, QT did not show significant effects on serum total protein, albumin, globulin, glucose,cholesterol and triglycerides concentrations. Supplementation of QT100 caused an increase(P < 0.05) of serum urea compared with that in control and QT_(200) groups. Generally, QT decreased(P < 0.05) serum creatinine concentration. Therefore, the supplementation of a commercial QT to early lactating Egyptian buffalo cows displayed negative consequences on their productive and reproductive performances.

关键词： Buffalo Tannins Milk traits Blood metabolites Ovarian follicles Conception rate

Investigation of multi-step fast charging protocol and aging mechanism for commercial NMC/graphite lithium-ion batteries

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Journal of Energy Chemistry 2023年第5期80卷 237-246,I0006页

作者： Yaqi Li Jia Guo Kjeld Pedersen Leonid Gurevich Daniel-Ioan Stroe department of Materials and production Aalborg UniversityAalborg 9220Denmark department of Energy Aalborg UniversityAalborg 9220Denmark

Fast charging is considered a promising protocol for raising the charging efficiency of electric vehicles.However,high currents applied to Lithium-ion(Li-ion)batteries inevitably accelerate the degradation and shorten their lifetime.This work designs a multi-step fast-charging method to extend the lifetime of LiNi0.5Co0.2Mn0.3O2(NMC)/graphite Li-ion batteries based on the studies of half cells and investigates the aging mechanisms for different charging methods.The degradation has been studied from both full cell behaviour and materials perspectives through a combination of non-destructive diagnostic methods and post-mortem analysis.In the proposed multi-step charging protocol,the state-of-charge(SOC)profile is subdivided into five ranges,and the charging current is set differently for different SOC ranges.One of the designed multi-step fast charging protocols is shown to allow for a 200 full equivalent cycles longer lifetime as compared to the standard charging method,while the charging time is reduced by 20%.From the incremental capacity analysis and electrical impedance spectroscopy,the loss of active materials and lithium inventory on the electrodes,as well as an increase in internal resistance for the designed multistep constant-current-constant-voltage(MCCCV)protocol have been found to be significantly lower than for the standard charging method.Post-mortem analysis shows that cells aged by the designed MCCCV fast charging protocol exhibit less graphite exfoliation and crystallization damage,as well as a reduced solid electrolyte interphase(SEI)layer growth on the anode,leading to a lower Rseiresistance and extended lifetime.

关键词： Fast-charging Lithium-ion battery Aging mechanism Electrode

Stature estimation from footprint measurements in Bangladeshi adults

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Forensic Sciences Research 2022年第2期7卷 124-131页

作者： Md Asadujjaman Md Harun Or Rashid Md Sohel Rana Md Mosharraf Hossain department of Industrial&production Engineering Rajshahi University of Engineering&TechnologyRajshahiBangladesh

The estimation of stature is very important in forensic investigation,as it provides useful data that can narrow the pool of potentially matching identities.The purpose of this study was to develop formulae for the estimation of stature from footprint measurements in Bangladeshi adults.This study included 118 randomly selected men and 130 randomly selected women,all aged 18–50 years.From each participant,stature and six footprint measurements were taken by means of standard measurement techniques.Footprint measurements were found to be positively correlated with stature.Stature was estimated by using linear regression equations.The right T1 length in men(R:þ0.587,R^(2):0.345)and the right T2 length in women(R:þ0.506,R^(2):0.256)were the most reliable individual estimators of stature.However,when data were combined for both sexes,the right T2 length was identified as the most reliable estimator of stature,with higher values of R(þ0.792)and R^(2)(0.627).In conclusion,human stature can be successfully estimated by using footprint measurements;this finding can be applied in forensic research and investigation.

关键词： Forensic sciences forensic anthropology anthropometry footprint stature estimation forensic identification

Secondary flows in statistically unstable turbulent boundary layers with spanwise heterogeneous roughness

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Theoretical & Applied Mechanics Letters 2022年第2期12卷 65-71页

作者： Ali Amarloo Pourya Forooghi Mahdi Abkar department of Mechanical and production Engineering Aarhus UniversityAarhus C8000Denmark

Large-scale secondary motions are known to occur in turbulent flows over surfaces with spanwise roughness heterogeneity.Numerical studies often use adjacent high-and low-roughness longitudinal strips to investigate these secondary rolls in boundary layers without any thermal stratification.In the present study,the effect of unstable thermal stratification on secondary rolls in a very high-Reynolds-number turbulent flow with spanwise-heterogeneous roughness is investigated by means of large-eddy simulation.The strength of the unstable stratification is systematically changed from L/h=−20 to L/h=−1,where L and h are Monin-Obukhov length and boundary-layer height,respectively.This range covers the transition from neutral stratification to unstable stratification.The results show that the positive buoyancy associated with the unstable thermal stratification acts against the roughness-induced secondary rolls.In the case of unstable stratification,secondary rolls are completely canceled out by buoyancy and replaced by new stronger convection-induced rolls rotating in opposite directions.

关键词： Secondary flows Roughness heterogeneity Unstable/convective boundary layer Large-eddy simulation

Integrated risk management: a Petrobras application in offshore well construction safety to minimize critical emergency disconnections

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Petroleum Science 2018年第2期15卷 421-431页

作者： Claudio Benevenuto de Campos Lima Pedro Esteves Aranha Jose Francisco Tebaldi de Castro Gilson Brito Alves Lima Augusto Borella Hougaz Felipe de Souza Terra Petrobras department of production Engineering Federal Fluminense University

In order to avoid mistakes and to save a great deal of time in analysis, an innovative methodology was developed that can analyze the well operations and rig characteristics involved to define the best emergency disconnect sequence （EDS） available. A solution was developed based on the characteristics of the rigs and blowout preventers （BOPs）, and six variables were considered that directly affect the choice of EDS. All possible combinations of 64 scenarios were analyzed, and the priority of choice of the EDS was defined empirically. This paper presents an approach to EDS risk management and examples of exposure time （time without riser safety margin and shear capability） for the same well, which can be lowered from 13% to 0.1%. The impact of this reduction is related to the ability of the BOP to cut some of the heavy casings, in addition to improved availability of EDS modes. This implementation opened up many possibilities for the performance of risk exposure analysis, enabling comparison of several BOP configurations of contracted rigs and selection of the best options. This innovative approach allowed a better management of the rig schedules, prioritizing safety aspects and making it possible to allocate the fleet in a systematic way.

关键词： Well safety Safety barriers Emergency disconnect sequence （EDS） Well control Kick Well design

Local injection of bone morphogenetic protein 7 promotes neuronal regeneration and motor function recovery after acute spinal cord injury

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Neural Regeneration Research 2018年第6期13卷 1054-1060页

作者： Chen Chen Guang-Chao Bai Hong-Liang Jin Kun Lei Kuan-Xin Li department of Joint and Spine Xinjiang Production and Construction Corps Hospital Urumqi

After spinal cord injury,the number of glial cells and motor neurons expressing bone morphogenetic protein 7（BMP7）increases,indicating that upregulation of BMP7 can promote nerve repair.We,therefore,tested whether direct injection of BMP7 into acutely injured ratalalo createrywith 50 ng BMP7（BMP7 group）or physiological saline（control group）for 7 consecutive days.Electrophysiological examination showed that the amplitude of N1 in motor evoked potentials（MEP）decreased after spinal cord injury.At 8 weeks post-operation,the amplitude of N1 in the BMP7 group was remarkably higher than that at 1 week post-operation and was higher than that of the control group.Basso,Beattie,Bresnahan scale（BBB）scores,hematoxylin-eosin staining,and western blot assay showed that at 1,2,4 and 8 weeks post-operation,BBB scores were increased;Nissl body staining was stronger;the number of Nissl-stained bodies was increased;the number of vacuoles gradually decreased;the number of synapses was increased;and the expression of neuronal marker,neurofilament protein 200,was increased in the hind limbs of the BMP7 group compared with the control group.Western blot assay showed that the expression of GFAP protein in BMP7 group and control group did not change significantly and there was no significant difference between the BMP7 and control groups.These data confirmed that local injection of BMP7 can promote neuronal regeneration after spinal cord injury and promote recovery of motor function in rats.

关键词： nerve regeneration behavior Basso Beattie Bresnahan scale score motor evoked potential wave Nissl staining neurons glial cells neurofilament protein 200 glial fibrillary acidic protein neural regeneration

Surface Modification Aspects for Improving Biomedical Properties in Implants:A Review

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 213-241页

作者： J.Sharath Kumar Rakesh Kumar Rajeev Verma Industrial and Production Department Dr B R Ambedkar National Institute of Technology JalandharJalandharPunjab144008India

The primary focus during surgery is to ensure successful implantation by achieving long-term and stable fixation of implants.Orthopaedic surgery is now more focused on the development of novel biomaterials intended to improve implant performance.To obtain a better understanding of metal implants,this article investigated the causes of material failures in certain cases and analysed a few case studies.The interaction between the implant and bone tissue was a crucial aspect of successful implantation,and this study explored the factors influencing this interaction as well as ways to improve it.Several modern approaches used for modifying implant surfaces were systematically illustrated and briefly analysed.Thermal spray coatings were often favoured because of their wide range of coating materials,but other substantial surface modifications(such as friction stir processing and laser surface texturing)were also used for a selection of applications.Notably,implant surfaces with desirable features,such as biocompatibility,antibacterial properties,corrosion resistance,and wear resistance,were essential for optimising implant functionality.This systematic review's main aim is to provide exhaustive reference information and a broad overview to advance the production and design of orthopaedic implants.

关键词： Biomaterials Surface treatments Thermal spray coatings Antibacterial Biocompatibility Corrosion resistance Wear resistance

Bioactive profile of borno brown Vigna unguiculata grains as influenced by pre-harvest synthetic chemicals

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Food Bioscience 2022年第1期45卷 223-231页

作者： Temitope Omolayo Fasuan Nneka Nkechi Uchegbu Titilope Modupe Olagunju Oyenike Olubunmi Falola department of Animal Health and production Technology Federal College of Animal Health and Production TechnologyIbadanNigeria department of Food Science and Technology University of NigeriaNsukkaNigeria department of Agricultural and Environmental Engineering Obafemi Awolowo UniversityIle-IfeNigeria

This study investigated the impact of pre-harvest synthetic chemical treatments on the post-harvest bioactive contents,pasting,colour,and thermal properties of borno brown V.unguiculata(L.)Walp grains.Seeds of borno brown V.unguiculata(L.)Walp was planted on an already ploughed,harrowed and ridged plot of land with a portion cultivated as organic and another non-organic.After 90 days,mature grains were harvested and analyzed using standard procedures.Results showed that a total of 44.33 g bioactive compounds/100g grain was present in the organic borno brown V.unguiculata grains whereas,20.56 g bioactive compounds/100g grain was present in the non-organic(control).The identified bioactive compounds in the organic grains included[heneicosane(4.50g/100g grain)];[12-Methyl-E,E-2,13-octadecadien-1-ol(4.09/100g grain)];[3-(2-Hydroxy-6-methylphenyl)-4(3H)-quinazolinone(7.40 g/100g grain)];[Methaqualone(9.08 g/100g grain)].The non-organic contained[heneicosane(4.07g/100g grain)];[3-(2-Hydroxy-6-methylphenyl)-4(3H)-quinazolinone(5.09 g/100g grain)];[Methaqualone(10.61 g/100g grain)].Flavonoids,alkaloids,total phenolic,2,2-diphenyl-1-picryl-hydrazl(DPPH)and ferric ion reducing antioxidant power(FRAP)contents of the organic grains were 19 mgRE/100g,3.40 mg/100g,1550 mgGAE/100g,2840μmolTEAC/100g,and 20.08 mmol Fe^(2+)/100g,respectively.The non-organic grains had flavonoids(11.31 mgRE/100g),alkaloids(1.86 mg/100g),total phenolic(1110 mgGAE/100g),DPPH(1779μmolTEAC/100g)and FRAP(12.24 mmol Fe^(2+)/100g).The peak viscosity of 111.52 RVU,final viscosity(141.25 RVU)and pasting temperature(82.01℃)were obtained for the organic grains while non-organic had peak viscosity of 93.10RVU,final viscosity(95.20 RVU)and pasting temperature(80.10℃).The colour parameters L^(*),a^(*),b^(*)and ΔE were 73.10,0.68,14.47 and 12.98 for the organic and 84.25,0.30,21.10,and 0.00,respectively for non-organic grains.The thermal property showed enthalpy(ΔH)and peak temperature(T_(p))of 3.12 J/g and 78.25℃ for organic,and 2.14 J/g and 76.28℃ for non-organ

关键词： Borno brown Vigna unguiculata grains Organic Bioactive compounds Phenolic compound profile Antioxidant activities Pasting property