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Transactions of Nonferrous Metals Society of China 2010年第9期20卷 1780-1785页

作者： h.Mller G.GOVeN DeR w.e.STUMPF Materials Science and Manufacturing Council for Scientific and Industrial Research (CSIR) Department of Materials Science and Metallurgic al engineering University of Pretoria

Since the automotive industry has many possible applications for semi-solid metal (SSM)-high-pressure die casting (hPDC) parts, the newly developed heat treatment cycles, as well as the traditional heat treatment cycles, were applied to A356 brake calipers cast using a LK DCC630 hPDC *** hardness measurements at a cross section of the brake calipers were performed, indicating that similar values can be obtained when using the significantly shorter heat treatment ***, the typical tensile properties that can be obtained for SSM-hPDC A356 brake calipers are compared with those manufactured by gravity die *** indicate that the differences in microstructures (globular or dendritic) do not have a noteworthy effect on the heat treatment *** implies that the short heat treatment cycles originally developed for globular SSM-hPDC A356 castings can be successfully applied to dendritic liquid A356 castings too.

关键词： semi-solid metal (SSM) forming heat treatment A356 brake caliper gravity die casting automotive

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(english edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAeI h.GhANDVAR e.JUMAeV S.KhATIR T.CUONG-Le School of Mechanical engineering Babol Noshirvani University of Technology Department of Mechanical engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for engineering Application and Technology Solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

关键词： Kinetic energy

Characterization of surface liquid segregation in SSM-hPDC aluminium alloys 7075,2024,6082 and A201

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中国有色金属学会会刊：英文版 2010年第S3期20卷 847-851页

作者： h.Mller U.A.CURLe e.P.MASUKU Materials Science and Manufacturing Council for Scientific and Industrial Research(CSIR)PretoriaSouth Africa

The surface liquid segregation(SLS) phenomenon in semi-solid metal-high pressure die casting(SSM-hPDC) plates of 7075,2024,6082 and A201 was investigated by different *** profiles were determined by firstly measuring the chemical composition of the surface of the plates using a Thermo Quantris optical emission spectrometer(OeS).Material was then removed by a grinding process followed by measurement of the amount of material removed and chemical *** profiles of the main alloying elements were plotted for the cross-section of the plates in the as-cast and T6(after solution treatment) temper *** hardness profiles from the surface to the centre of the plates were *** samples of cross-sections of the castings were prepared and evaluated using a scanning electron *** results show that surface liquid segregation in SSM-hPDC alloys causes significant differences in properties between the surface and the bulk of these castings in both the F and T6 temper conditions.

关键词： semi-solid metal(SSM) forming alloy 7075 alloy 2024 alloy 6082 alloy A201 surface liquid segregation

Measurement of the pion form factor for M_(ππ)～2 between 0.1 and 0.85 GeV^2 with the KLOe detector

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Chinese Physics C 2010年第6期34卷 686-691页

作者： Stefan e.Müller Institut für Kernphysik Johannes Gutenberg-Universitt

The KLOe experiment at the φ-factory DAФPNe has measured the pion form factor in the range between 0.1 〈 Mππ^2 〈 0.85 GeV^2 using events taken at √s = 1 GeV with a photon emitted at large polar angles in the initial state. This measurement extends the Mππ^2 region covered by KLOe ISR measurements of the pion form factor down to the two pion production threshold. The value obtained in this measurement of the dipion contribution to the muon anomalous magnetic moment of △αμ^ππ= （478.5±2-0stat±4.8syst±2.9theo）·10^-10 further confirms the discrepancy between the Standard Model evaluation for αμ and the experimental value measured by the （g-2） collaboration at BNL.

关键词： hadronic cross section initial state radiation pion form factor muon anomaly

Does mesenchymal stem cell’s secretome affect spinal sensory circuits?Implication for pain therapies

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Neural Regeneration Research 2025年第1期20卷 181-183页

作者： Francesco Ferrini esri h.Juárez Adalberto Merighi Department of Veterinary Sciences University of TurinGrugliascoTOItaly Department of Psychiatry and Neuroscience UniversitéLavalQuébec CityQCCanada

Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical *** have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue *** enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MSC *** increasing number of pre-clinical studies suggest that delivering in vivo an MSC-conditioned medium(i.e.,the medium collected from MSC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions.

关键词： protective clinical collective

Carbon dioxide capture by solvent absorption using amino acids: A review

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Chinese Journal of Chemical engineering 2018年第11期26卷 2229-2237页

作者： Guoping hu Kathryn h.smith Yue wu Kathryn A.Mumford Sandra e.Kentish Geoffrey w.Stevens Peter Cook Centre for Carbon Capture and Storage Research (PCC) Particulate Fluids Processing Centre (PFPC)Department of Chemical EngineeringThe University of Melbourne

The emission of large amounts of carbon dioxide is of major concern with regard to increasing the risk of climate change. Carbon capture, utilisation and storage (CCUS) has been proposed as an important pathway for slowing the rate of these emissions. Solvent absorption of CO_2 using amino acid solvents has drawn much attention over the last few years due to advantages including their ionic nature, low evaporation rate, low toxicity, high absorption rate and high biodegradation potential, compared to traditional amine solvents. In this review, recent progress on the absorption kinetics of amino acids is summarised, and the engineering potential of using amino acids as carbon capture solvents is discussed. The reaction orders between amino acids and carbon dioxide are typ- ically between 1 and 2. Glycine exhibits a reaction order of 1, whilst, by comparison, lysine, proline and sarcosine have the largest reaction constants with carbon dioxide which is much larger than that of the benchmark solvent monoethanolamine (MeA). Ionic strength, p h and cations such as sodium and potassium have been shown to be important factors influencing the reactivity of amino acids. Corrosivity and reactivity with impurities such as SOx and NOxare not considered to be significant problems for amino acids solvents. The precipitation of CO_2 loaded amino acid salts is thought to be a good pathway for increasing CO_2loading capacity and cutting desorption energy costs if well-controlled. It is recommended that more detailed research on amino acid degradation and overall process energy costs is conducted. Overall, amino acid solvents are recognised as promising potential solvents for car- bon dioxide capture.

关键词： Amino acids Carbon capture Absorption Solvents

Influence of surface liquid segregation on corrosion behavior of semi-solid metal high pressure die cast aluminium alloys

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中国有色金属学会会刊：英文版 2010年第S3期20卷 837-841页

作者： e.P.MASUKU h.Mller U.A.CURLe P.C.PISTORIUS Materials Science and Manufacturing Council for Scientific Industrial ResearchPretoriaSouth Africa Department of Materials Science and engineering Carnegie Mellon UniversityPittsburghUSA

The corrosion behavior(in chloride medium) of the surface layer of SSM-hPDC plates of alloys 7075-T6 and 2024-T6 was compared with that of the wrought alloys 7075-T6 and *** testing was performed in deaerated 3.5%NaCl *** separate tests,the open-circuit potential was monitored in aerated 3.5% NaCl for 30 min after *** electrochemical tests show that there is no significant difference in the pitting potential of the wrought alloys and that of the Cu-enriched surfaces of the SSM-hPDC alloys.

关键词： semi-solid metal(SSM) forming wrought aluminium alloys alloy 7075 alloy 2024 corrosion surface liquid segregation

PhOSPhORUS ReMOVAL USING STeeL SLAG

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Acta Metallurgica Sinica(english Letters) 2006年第6期19卷 449-454页

作者： R.w. smith Metallurgical and Materials Department Nevada University of Reno NV89503 Nevada USA

Steel slag is a byproduct produced in large amounts in the steel-making process. It is an important resource that can be effectively utilized. An experiment was described in which steel slag was tested as an adsorbent for the removal of phosphorus from waste water. Phosphorus removal depended on the amount of steel slag added, the ph value, the contact time, and the initial concentration. Under laboratory conditions when the added slag was 7.5g/L, the contact time 2h, and the ph value was equivalent to 6.5, over 99% of the phosphorus was removed; the experimental data on steel slag adsorption of phosphorus in the water fitted the Freundlich isotherm model. Steel slag was found to be very effective in adsorbing phosphorus.

关键词： steel slag waste water phosphorus removal

Influence of elevated Fe,Ni and Cr levels on tensile properties of SSM-hPDC Al-Si-Mg alloy F357

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中国有色金属学会会刊：英文版 2010年第S3期20卷 842-846页

作者： h.Mller w.e.STUMPF P.C.PISTORIUS Materials Science and Manufacturing Council for Scientific and Industrial Research(CSIR)PretoriaSouth Africa Department of Materials Science and Metallurgical engineering University of PretoriaPretoriaSouth Africa Department of Materials Science and engineering Carnegie Mellon UniversityPittsburghUnited States of America

The microstructures and tensile properties of semi-solid metal high pressure die cast(SSM-hPDC) F357 alloys with low and high levels of Fe,Ni and Cr were compared in different temper *** software was used to predict the different intermetallics that can be expected in the alloys,and scanning electron microscopy(SeM) with energy dispersive spectroscopy(eDS) was used to investigate the actual intermetallics that *** influence of these intermetallics on tensile properties was *** results show that lower strength is obtained in the alloy with high Fe,Ni and Cr *** is attributed mainly to the formation of more π-Al8FeMg3Si6 phase,which removes strengthening Mg atoms from solid ***,the ductility of the high Fe,Ni and Cr levels alloy is decreased significantly due to microcracking of the higher volume fraction π-Al8FeMg3Si6 and Al9FeNi *** combination of lower strength and ductility results in a decrease of the quality index of this alloy compared with the alloy with low levels of Fe,Ni and Cr.

关键词： semi-solid metal(SSM) forming alloy F357 heat treatment intermetallics π-Al8FeMg3Si6 Al9FeNi β-Al5FeSi

Adjustment of the annual cycle to climatic change in a long-lived migratory bird species

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Current Zoology 2009年第2期55卷 92-101页

作者： A. P. MФller e. FLeNSTeD-JeNSeN w. MARDAL3 Laboratoire d'ecologie Systématique et EvolutionCNRS UMR 8079Université Paris-SudBatiment 362F-91405 Orsay CedexFrance Cypresvej 1 DK-9700 BrФnderslevDenmark Legindvej 102 SФnderhDK-7752 SnedstedDenmark

Climate change has advanced the phenology of many organisms. Migratory animals face particular problems because climate change in the breeding and the wintering range may be asynchronous, preventing rapid response to changing conditions. Advancement in timing of spring migration may have carry-over effects to other parts of the annual cycle, simply because advancement of one event in the annual cycle also advances subsequent events, gradually causing a general shift in the timing of the entire annual cycle. Such a phenotypic shift could generate accumulating effects over the years for individuals, but also across generations. here we test this novel hypothesis of phenotypic response to climate change by using long-term data on the Arctic tern Sterna paradisaea. Mean breeding date advanced by almost three weeks during the last 70 years. Annual arrival date at the breeding grounds during a period of 47 years was predicted by environmental conditions in the winter quarters in the Southern Ocean near the Antarctic and by mean breeding date the previous year. Annual mean breeding date was only marginally determined by timing of arrival the current year, but to a larger extent by arrival date and breeding date the previous year. Learning affected arrival date as shown by a positive correlation between arrival date in year （i ＋ 1） relative to breeding date in year （i） and the selective advantage of early breeding in year （i）. This provides a mechanism for changes in arrival date being adjusted to changing environmental conditions. This study suggests that adaptation to changing climatic conditions can be achieved through learning from year to year

关键词： Arctic tern Arrival date Climate change Migration Southern Oscillation Sterna paradisaea