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Cu和mg对2014铝合金触变成形性和力学性能的影响（英文）

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Transactions of Nonferrous metals society of China 2020年第2期30卷 275-287页

作者： m.A.m.ARIF m.Z.OmAR Z.sAJURI m.s.salleh Centre for materials Engineering and smart manufacturing(mERCU) Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia43600SelangorMalaysia Department of manufacturing Process Faculty of Manufacturing EngineeringUniversiti Teknikal MelakaHang Tuah Jaya76100 Durian TunggalMelakaMalaysia

触变成形是使金属在半固态时发生变形的一种加工方法。该工艺的优点包括具有良好的表面光洁度,细小的显微组织和优越的力学性能,然而,该工艺主要是用铝铸件生产零件,没有充分利用其真正潜力。因此,可用热力学模拟进行合金成分设计。研... 详细信息

触变成形是使金属在半固态时发生变形的一种加工方法。该工艺的优点包括具有良好的表面光洁度,细小的显微组织和优越的力学性能,然而,该工艺主要是用铝铸件生产零件,没有充分利用其真正潜力。因此,可用热力学模拟进行合金成分设计。研究减少铜含量和增加硅、镁含量对2014铝合金触变成形的影响,包括模拟和实验验证两部分。结果表明,增加合金中硅含量和降低铜含量,可以降低合金的凝固区间温度,扩大特定液相分数之间的工作温度窗口,这对该工艺有利。高的固溶温度导致mg2si化合物的分解。mg含量的增加导致致密π-Al8Femg3si6相的形成和尖片状结构β-Al5Fesi相的减少,提高合金的强度。后续T6热处理进一步提高改性合金的强度。

关键词： JmatPro 锻造2014铝合金触变成形半固态加工力学性能

Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： s.m.Yakout A.m.Youssef Inorganic Chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount significance.In the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on sEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher charge carriers' separation(Cu^(2+)+ e-→ Cu^(+), L

关键词： semiconductor TiO_(2) Rare earths Congo red methylene blue solar spectrum Photodegradation

Direct microwave leaching conditions of rare earth elements in fluorescent wastes

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Journal of Rare Earths 2024年第6期42卷 1165-1174,I0007页

作者： A.Bilen B.Birol m.N.saridede s.s.Kaplan m.s.sonmez Department of metallurgical and materials Engineering Yildiz Technical UniversityIstanbulTurkey Department of Chemical Engineering and materials science Stevens Institute of TechnologyNew JereyUSA Department of metallurgical and materials Engineering Istanbul Technical UniversityIstanbulTurkey

The luminescent phosphor powder in the fluorescent lamp constitutes 2%of the lamp’s weight.It can be mentioned that fluorescent wastes are a crucial raw material to produce rare earth oxides.In the present study,microwave leaching process was conducted to dissolve rare earth elements yttrium(Y),europium(Eu),and remaining rare earth elements(REEs)present in the phosphor powder of the fluorescent lamp.and the yields were compared.In the microwave leaching process,the effects of the temperature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HNO_(3)),sulphuric acid(H_(2)sO_(4))),acid concentration(0.5-6 mol/L),solid to liquid ratio(0.1:10-0.5:10)and reaction time(5-90 min)parameters on leaching efficiencies of varying rare earth elements and calcium were investigated.The highest yield was obtained in the direct microwave leaching of fluorescent waste with the experimental conditions of 6 mol/L HCl,160℃,0.1:10 solid-to-liquid ratio(s:L),and 90 min.Activation energy calculations were made,and kinetic models of the reactions were obtained,and it is observed that Y and Eu dissolution is diffusion-controlled,on the other hand,lanthanum(La),cerium(Ce),and terbium(Tb)were examined to be chemical reaction controlled.moreover,calcium(Ca)and gadolinium(Gd)seem coherent with the mixed model.Concurrently,mathematical models of all experimental studies are created with the response surface Box-Behnken method and the correlation coefficients of all the models are over 90%.

关键词： Rare earth elements(REEs) Direct microwave leaching Fluorescent waste Kinetic models Response surface method

Complexed amino acid minerals vs. bis-glycinate chelated minerals:Impact on the performance of old laying hens

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Animal Nutrition 2024年第1期16卷 395-408页

作者： marcos J.B.santos maria C.m.m.Ludke Leandro m.silva Carlos B.V.Rabello mércia R.Barros Fabiano s.Costa Clariana s.santos Jamille s.s.Wanderley Department of Animal science Rural Federal University of Pernambuco Department of Veterinary science Rural Federal University of Pernambuco

The present study was to evaluate the effect of trace minerals(Zn, mn, and Cu) from complexed amino acid minerals(ZmCAA) and bis-glycinate chelated minerals(ZmCGly) in laying hen diets on performance,internal and external egg quality, yolk mineral deposition, intestinal morphometry, and bone characteristics. From 78 to 98 weeks of age, 400 White LsL-Lite strain laying hens were distributed in a randomized design with 4 treatments with 10 replicates per treatment. Treatments were distributed in a 2 ×2 factorial arrangement using either Zn, mn, and Cu of ZmCAA or ZmCGly source at 2 levels: low(20, 20,and 3.5 mg/kg of Zn, mn, and Cu, respectively) or high(40, 40, and 7 mg/kg of Zn, mn, and Cu,respectively). The analysis of variance was performed, and in cases where differences were observed, the means were compared using Tukey?s test(P source and level of trace mineral supplementation had a significant impact on the performance of laying hens. Hens fed ZmCAA had higher egg production(P = 0.01), egg weight(P = 0.02), egg mass(P = 0.01), and lower feed conversion ratio(P =0.05) compared to those fed ZmCGly. The ZmCAA supplementation showed higher albumen height(P =0.01), albumen weight(P = 0.01), and eggshell thickness(P sition of Zn(P mn(Ps greater for hens received ZmCAA. Tibia weight(P = 0.04)and bone densitometry(P mCAA supplementation. In the small intestine, ZmCAA resulted in longer villi(P = 0.02) and shorter crypt depth(P = 0.01) in the duodenum.Jejunum and ileum measurements were influenced by the level and source of trace minerals(P s fed ZmCAA exhibited superior performance, egg quality, deposition of trace minerals in the egg yolk, and bone density compared to hens fed ZmCGly. In this study, older laying hens supplemented with ZmCAA at lower levels demonstrated adequate levels of supplementation.

关键词： Bis-glycinates metal-amino acids Radiodensity Trace minerals

Background removal from global auroral images:Data-driven dayglow modeling

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Earth and Planetary Physics 2024年第1期8卷 247-257页

作者： A.Ohma m.madelaire K.m.Laundal J.P.Reistad s.m.Hatch s.Gasparini s.J.Walker Birkeland Centre for space science Department of Physics and TechnologyUniversity of BergenBergenNorway

Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth environment.However,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but also to dayglow emissions produced by photoelectrons induced by sunlight.Nightglow emissions and scattered sunlight can contribute to the background signal.To fully utilize such images in space science,background contamination must be removed to isolate the auroral signal.Here we outline a data-driven approach to modeling the background intensity in multiple images by formulating linear inverse problems based on B-splines and spherical harmonics.The approach is robust,flexible,and iteratively deselects outliers,such as auroral emissions.The final model is smooth across the terminator and accounts for slow temporal variations and large-scale asymmetries in the dayglow.We demonstrate the model by using the three far ultraviolet cameras on the Imager for magnetopause-to-Aurora Global Exploration(ImAGE)mission.The method can be applied to historical missions and is relevant for upcoming missions,such as the solar wind magnetosphere Ionosphere Link Explorer(smILE)mission.

关键词： aurora dayglow modeling global auroral images far ultraviolet images dayglow removal

镁含量对触变成形A319合金显微组织演变和力学性能的影响（英文）

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Transactions of Nonferrous metals society of China 2016年第8期26卷 2029-2042页

作者： m.s.salleh m.Z.OmAR K.s.ALHAWARI m.N.mOHAmmED m.A.mAD ALI E.mOHAmAD Department of manufacturing Process Faculty of Manufacturing Engineering Universiti Teknikal Malaysia Melaka Department of mechanical and materials Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia Department of Engineering and Technology Faculty of Information Sciences and EngineeringManagement and Science University

研究不同镁含量对触变成形A319合金显微组织和拉伸性能的影响。合金在含50%液相时进行触变成形,并对部分合金进行T6热处理。采用光学显微镜、扫描电子显微镜、能量散射谱、X射线衍射和拉伸试验对合金进行表征。结果表明,镁可以细化合金... 详细信息

研究不同镁含量对触变成形A319合金显微组织和拉伸性能的影响。合金在含50%液相时进行触变成形,并对部分合金进行T6热处理。采用光学显微镜、扫描电子显微镜、能量散射谱、X射线衍射和拉伸试验对合金进行表征。结果表明,镁可以细化合金中共晶硅。当镁含量为1.0%和1.5%时,合金中形成致密的Al9Fe mg3si5相。随着镁含量的增加,触变成形合金的拉伸强度增加。热处理后的触变成形A319合金的抗拉强度、屈服强度和伸长率分别为298 mPa,201 mPa和4.5%。而对于添加1.5%mg的触变成形A319合金,其热处理后的抗拉强度、屈服强度和伸长率分别为325 Pa、251 mPa和1.4%。触变成形A319合金表现为韧窝断裂,而添加1.5%mg的A319合金表现为混合断裂,在合金表面可观察到韧窝断裂和解理断裂。

关键词：铝合金触变成形 T6热处理力学性能

Parametric investigation on the novel and cost-effective nano fly ash impregnated geopolymer system for sustainable construction

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Frontiers of structural and Civil Engineering 2024年第2期18卷 170-183页

作者： R.mOHANA s.m.Leela BHARATHI Department of Civil Engineering Mepco Schlenk Engineering CollegeSivakasi 626123India

The hazardous environmental effects of greenhouse gas emissions and climate change demand alternative sources for cementitious materials in the construction industry.The development of geopolymer structures provides a way of producing 100%cement-free construction.In this research work,a novel and simple way of deriving nano particles from waste fly ash particles is promoted.The effect of adding the synthesized nano fly ash particles as a filler medium in geopolymer mortars was investigated by considering strength and durability properties.Parameter optimization was done by using regression analysis on the geopolymer mortar and the impact of adding nano fly ash particles was studied by varying different percentages of addition ranging from 0 to 7.5%by weight of binder content.From the results,it was observed that 1%nano fly ash acted not only as a filler but also as nano-sized precursors of the polymerization process,resulting in denser geopolymer medium.This can explain the extraordinary gain in strength of 72.11 mPa as well as the denser core with negligible level of chloride ion penetration,making the material suitable for the development of structures susceptible to marine environment.

关键词： geopolymer nano fly ash chloride ion penetration durability polymerization fillers

In search of a pan-coronavirus vaccine:next-generation vaccine design and immune mechanisms

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Cellular & molecular Immunology 2024年第2期21卷 103-118页

作者： s.Cankat m.U.Demael L.swadling Division of Infection and Immunity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

members of the coronaviridae family are endemic to human populations and have caused several epidemics and pandemics in recent history.In this review,we will discuss the feasibility of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all members of the coronavirus family.We will detail the unmet clinical need associated with the continued transmission of sARs-CoV-2,mERs-CoV and the four seasonal coronaviruses(HCoV-OC43,NL63,HKU1 and 229E)in humans and the potential for future zoonotic coronaviruses.We will highlight how first-generation sARs-CoV-2 vaccines and natural history studies have greatly increased our understanding of effective antiviral immunity to coronaviruses and have informed next-generation vaccine design.We will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of immunity that may offer cross-protection.Finally,we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly or universally protective vaccines for coronaviruses.

关键词： Vaccine Coronavirus Cross-reactive immunity Cross-protection Universal

QCD sum rule study of J^(P)=1^(±)exotic states with two heavy quarks in the molecular picture

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Chinese Physics C 2024年第6期48卷 31-37页

作者： T.m.Aliev s.Bilmis m.savcı Department of Physics Middle East Technical UniversityAnkara06800Turkey TUBITAK ULAKBIm Ankara06510Turkey

In this study,the spectroscopic parameters of exotic molecular states composed of mesons containing two heavy quarks(scalar-axial and pseudoscalar-axial meson combinations)are investigated within the QCD sum rules.Our findings reveal that molecular states containing charm quarks do not form bound states,whereas states with b-quarks can form exotic molecular states.This observation has significant implications for understanding the structure of these exotic states.

关键词： QCD sum rules exotic mesons molecular states