Дисертації з теми "Pure mg"
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Han, Junsoo. "L'électrochimie et désalliage de Zn-Mg/Al-Zn phase pures et l'importance sur la corrosion de l'alliage Zn-Al-Mg." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEC014.
Повний текст джерелаThe objective of this Ph.D. project is to investigate the electrochemistry of the pure phases, components of the Zn-Al-Mg coating alloys. The electrochemical data was used as an input for the prediction of corrosion behavior of the multi-phase alloy coatings. To this end, a database of elemental polarization curves was established as a function of pH by using atomic emission spectroelectrochemistry (AESEC). Dealloying of the MgZn2 intermetallic and α-phase of Al-Zn (Zn-68Al) were investigated at pH=10.1 represent the extremes of Mg and Al content in the Zn-Al-Mg alloy coating, respectively. In the cathodic polarization, the Zn(0) enriched layer was formed in both cases by selective dissolution of Mg and Al, respectively. However, the influence of this layer on cathodic dealloying differed: for MgZn2, Mg selective dissolution was restrained by the dealloyed layer, whereas for Zn-68Al, Al selective dissolution was not affected by this layer. It was observed that the onset of active Zn dissolution coincided with a reduction in the Al dissolution rate, suggesting an inhibitive effect of Zn dissolution on Al dissolution. It was observed that Al dissolution in alkaline media was limited by the dissolution rate of the Al(OH)3 film, evidenced by potential independent Al dissolution. The most stable corrosion products formed by electrochemical measurements, precipitated species in the solution during titration experiment and the thermodynamic simulation were reasonably coherent with each other. Most of the precipitated species formed in the solution corresponded reasonably well to those predicted by thermodynamic database. It was in a good agreement with the corrosion products of the alloy, characterized after the electrochemical measurements. Therefore, it can be concluded that the thermodynamic database can be used to predict and eventually model the real corrosion situation
Li, Ping. "Low cycle fatique behaviour of pure aluminium and Al-Zn-Mg-Cu alloy between 20 and 260° C /." [S.l.] : [s.n.], 1988. http://library.epfl.ch/theses/?nr=735.
Повний текст джерелаSubbarayan, Sapthagireesh. "Fabrication of a Novel Al/Mg Composite: : Processing and Characterization of Pure Aluminium, Al/AZ31 Alloy Bi-Metal and Aluminium based Sheet Composites by Severe Plastic Deformation." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for materialteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-23778.
Повний текст джерелаAraújo, Márcia de Mesquita. "Henriqueta Lisboa: teoria e prática de poesia pura." www.teses.ufc.br, 2013. http://www.repositorio.ufc.br/handle/riufc/11171.
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Esta pesquisa consiste fundamentalmente no estudo crítico de uma seleção de poemas de Henriqueta Lisboa, em especial da obra Flor da morte (1949), naquilo que ela tem de “poesia pura”, segundo concepções estabelecidas a partir das pesquisas de autores que se pronunciam sobre o tema, como Henri Brémond, Henry Decker, Paul Valéry e Robert Penn Warren, e considerando as concepções de poesia expressas pela própria poeta em seus textos ensaísticos. Consideramos, também, textos de estudiosos da obra de Henriqueta Lisboa e da “poesia pura”, como forma de enriquecer nosso estudo, buscando refletir e tentar responder a alguns questionamentos: como a “poesia pura” comparece na obra de Henriqueta Lisboa? A partir dessa inquisição surgem, por conseguinte, outras indagações: em que quantidade, em quais poemas da obra Flor da Morte, segundo qual conceito de poesia pura, em que possível diversidade de manifestações? O fundamento teórico da pesquisa provém de teóricos como de Giorgio Agamben, Jacques Derrida, Emanuel Levinas, Maurice Blanchot, principalmente, Martin Heidegger, entre outros. Por fim, relacionamos os textos estudados para o estabelecimento das conclusões, acrescidas das possibilidades de descobertas geradas por essas leituras, além de levantarmos questões relativas à arte, à literatura brasileira, à escritura, especialmente, e a crítica literária contemporânea, de forma enriquecida e sistematizada, tudo sob o viés da literatura contemporânea.
Barbosa, Willer Araujo. "Cultura Purí e educação popular no município de Araponga, Minas Gerais." Florianópolis, SC, 2005. http://repositorio.ufsc.br/handle/123456789/102780.
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Análise do processo variável da emergência étnica no entorno do Parque Estadual da Serra do Brigadeiro na Zona da Mata de Minas Gerais. A Cultura Puri foi silenciada durante os últimos duzentos anos, a partir da Educação Popular, seu processo intercultural possibilitou a recriação de identidades. Através de entrevistas, de rodas de narração de histórias e das notas de campo em comunidades rurais recupera fontes orais. Capta um encadeamento discursivo recorrente entre violência, fabulações naturalísticas e vontade de liberdade. Se inscreve na tradição da crítica cultural como motor da transformação social. Associa-se à saga colonial migratória, e recoloca a temática dos movimentos sociais. Critica o monoculturalismo do saber através da inteligibilidade dos movimentos sociais e da ecologia de saberes. Enfatiza a constituição de uma outra temporalidade e da dilatação do tempo presente, o que aprofunda as análises de longa duração. Aborda conceitos que se interrelacionam complexamente, tais como: estrutura de sentimentos, hegemonia, residual e emergencial. Toma como referências os estudos de Raymond Williams e de Boaventura de Sousa Santos.
Al, Bacha Serge. "Générateur d’Hydrogène « vert » pour mobilité légère ou de courte distance Hydrogen generation via hydrolysis of ball milled WE43 magnesium waste Hydrogen generation from ball milled Mg alloy waste by hydrolysis reaction Effect of ball milling strategy (milling device for scaling-up) on the hydrolysis performance of Mg alloy waste Effect of ball milling in presence of additives (Graphite, AlCl3, MgCl2 and NaCl) on the hydrolysis performances of Mg17Al12 Corrosion of pure and milled Mg17Al12 in “model” seawater solution Mechanism of hydrogen formation during the corrosion of Mg17Al12 Hydrolysis properties, corrosion behavior and microhardness of AZ91 "model" alloys SECM investigation of galvanic coupling between Mg and Mg17Al12 in AZ alloys Valorization of AZ91 by the hydrolysis reaction for hydrogen production (Electrochemical approach) Clean hydrogen production by the hydrolysis of Magnesium-based material: effect of the hydrolysis solution." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0312.
Повний текст джерелаThe hydrolysis of magnesium alloys wastes in seawater (i.e. 3.5 wt.% of NaCl aqueous solution) is a new approach which allows both in-situ hydrogen production and the valorization of a priori non-recyclable wastes. The objective of this research work is to optimize the reactivity of magnesium-based wastes by ball milling with additives. Therefore, we investigated the effects of the main milling parameters (e.g. milling atmosphere, milling rotation speed, order of the addition of additives) on the reactivity of WE43 alloys and Mg – Al alloys wastes. A « scale-up » of the materials treatment process was conducted to explore the possibility of industrializing the process. In addition, we have shown that milling under argon is more advantageous than under hydrogen.Mg – Al alloys (more precisely AZ91) are the most widely used. In these alloys, Al forms with Mg the intermetallic Mg17Al12. To better understand the mechanism of hydrogen production from these binary Mg – Al alloys (Mg + Mg17Al12), evaluating the behavior of each of their constituents and their interactions is essential. In this regard, the chemical (i.e. hydrolysis) and electrochemical (i.e. corrosion) aspects of the reaction of Mg17Al12 with the model seawater solution and the effect of milling in the presence of additives (e.g. graphite, NaCl, MgCl2 and AlCl3) were studied. The evolution of the surface chemistry during polarization tests has proven experimentally (by Raman spectroscopy), for the first time, the formation of reaction intermediate and has allowed us to propose a mechanism of H2 formation.The interaction between Mg and Mg17Al12 was explored by comparing the properties of model materials of « AZ91 » (Mg + Mg17Al12). Using scanning electrochemical microscopy, the effect of galvanic coupling was studied at the interface of the two components of the material. In view of these studies, the contribution of Mg17Al12 in the corrosion of AZ91 alloys was clarified. The intermetallic is corrosion resistant and accelerates the corrosion of Mg due to galvanic coupling. The various milling strategies adopted in this work were compared by applying them to a commercial AZ91 alloy. Mechanical treated materials with graphite and AlCl3 showed the highest hydrolysis performances.Finally, we semi-quantitatively evaluated the purity of H2 (the composition of the gas mixture and its humidity) produced. The impact of few experimental conditions (e.g. composition of the solution, temperature, ratio of the mass of powder to the volume of solution) is reported. Thus, it has been shown that an Mg hydrolysis reactor operating at room temperature with seawater produces « clean » hydrogen in-situ and can be considered as a « green » hydrogen on demand generator
SCHOEFFEL, JEAN-PHILIPPE. "Etude des fluctuations structurales dans le compose cugeo3 pur et ses alliages au si, al, mg, ni, zn, et ti." Paris 11, 1998. http://www.theses.fr/1998PA112289.
Повний текст джерелаAlmeida, Sérgio Antônio de Paula. "No livro a raiz, na lembrança o passado: Fragmentos Culturais e Memória dos descendentes declarados de indígenas de Mirai." Universidade Federal de Viçosa, 2016. http://www.locus.ufv.br/handle/123456789/10011.
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Após séculos de opressão e de lutas, muitos dos grupos indígenas brasileiros sobreviveram apenas nas narrativas da história. Contudo, em alguns casos, eles deixaram fragmentos de cultura entrelaçados aos modo de vida urbana na atualidade. Na Zona da Mata mineira, região das últimas fronteiras liberadas para ocupação territorial a partir do último quarto do século XVIII e início do século XIX, encontrou-se registros paroquiais de batismos com evidências de resistência de um desses povos de floresta, o povo indígena Puri. Estes índios habitaram também no território da atual cidade de Miraí, antiga Freguesia de Santo Antônio do Muriahé, e parte de suas tradições estão mantidas, ainda que de forma esmaecida, como fragmentos de cultura ancestral presentes nas famílias que se auto-declaram como descendentes deste povo de floresta. Investigá-las no entanto, é um exercício da memória.
After centuries of oppression and fights, many aborigine Brazilians groups survived just in the narratives of history. However, in some cases, they culture. They left fragments of the culture interlaced the urban way of life in the present. The Forest Zone of Minas Gerais, of the last frontiers released for territorial occupation form the last quarter of the eighteenth century and early nineteenth century. We found registration of documents of Parish church of baptism with evidence of resistance to one of these people of the forest, the Puri aborigine. These aborigines also lived in the territory at the present Miraí, older Parish of Santo Antonio do Muriahé, and part of their traditions are maintained. Still dimmed form, an ancestral culture fragments investigate them. However, it is an exercise of memory.
Marty, Ludovic. "Etude numérique et expérimentale d'une onde de choc induite par impact laser dans une cible solide." Poitiers, 1988. http://www.theses.fr/1988POIT2273.
Повний текст джерелаHagège, Serge. "Contribution a l'etude des joints de grains en coincidence dans la symetrie hexagonale." Caen, 1985. http://www.theses.fr/1985CAEN2019.
Повний текст джерелаJaouen, Christiane. "Etude des mécanismes des transformations de phase induites par irradiation aux ions dans les systèmes métalliques." Poitiers, 1987. http://www.theses.fr/1987POIT2019.
Повний текст джерелаBRAGA, ANIKA. "INTERVENTI NEL PROCESSO DI PRODUZIONE DELLE BEVANDE FERMENTATE PER UN MIGLIORAMENTO GUSTO - OLFATTIVO E IGIENICO - SANITARIO DEI PRODOTTI." Doctoral thesis, Università Cattolica del Sacro Cuore, 2009. http://hdl.handle.net/10280/421.
Повний текст джерелаSelected microrganisms are important as agents of the main processes of transformation of the raw materials in fermented product but also as responsible of the improvement in the shelf-life, texture, taste, aroma, as well as safety and nutritional value. The market globalization made us to consider not only popular food and/or beverage in Europe but also in non European countries. In this research I consider wine and cassava products. As regards wine the aim is to improve the Ortrugo wine typicalness by Saccaromyces cerevisiae autochtonous strains. In spontaneous fermentations the yeasts vary according to geography location, climatic conditions and/or grape variety. Some researchers believe that each micro-environment is characterised by specific Saccaromyces cerevisiae that may enhance the grape flavours. Unfortunately spontaneous fermentations may cause off-flavours and fermentation stuck. The selected yeast inoculum in must is one of the consolidated practices to eliminate the risks of spontaneous fermentation, but these yeast are not able to emphasise the characters of grape variety because they are from different ecosystems. Autochthonous yeasts e.g. yeasts isolated from a definite micro-environment are adapted to operate in a must whose characteristics are determined by the variety of the grapes and the “terroir” and, therefore, they able to enhance the peculiarities of a wine. As regards the cassava (Manihot esculenta Crantz) selected microorganisms will be used to reduce the cyanogenic glucosides (mainly linamarin and lotaustralin) toxic molecules. Consumption of cassava and its products may cause cyanide poisoning with symptoms of vomiting, nausea, dizziness, stomach pains, weakness, headache and diarrhoea and occasionally death. Cyanide intake from cassava is almost certainly the cause of Konzo (irreversible paralysis of the legs) in eastern, central and southern Africa. The World Health Organisation (WHO) has set the safe level of cyanogens in cassava flour at 10 ppm (FAO/WHO, 1991).
Tsai, Wei-Pin, and 蔡韋平. "Fabrication of pure, Metal (Mn, Mg) doped ZnO single nanowire based CO sensors." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/20278454322105853229.
Повний текст джерела國立中興大學
奈米科學研究所
105
Zinc oxide (ZnO) is a wide band gap (~3.37 eV) and higher excitation energy (~60 meV) at room temperature (RT) semiconductor. These characteristics allow ZnO been widely used in photo-electric devices. In this study, we use spin-coating to make ZnO seed layer, then fabricate massive single crystalline ZnO nanowires(NWs) by using aqueous solution method at 90 ˚C for 3 hours. We also use some other elements (eg. Mn, Mg …etc) to make dopant at ZnO NWs. The morphology of ZnO NWs has been examined by SEM. The XRD diffraction spectrum demonstrates that the ZNO NWs growing by aqueous solution method are single crystalline along the (002) direction. The TEM also shows the same result. We used Raman spectrum, XPS spectrum …etc instrument to study the material characteristics. We can checked that the ZnO nanowires were mainly wurtzite structure by using Raman spectrum, and the XPS spectrum showed that the orbital of ZnO is mainy 2p3/2 and sp1/2. We can fabricated single ZnO nanowires devices by using FIB, and measuring the IV curve of each devices and measure the CO sensing at room temperature. The sensing results showed that the pure ZnO nanowires on sapphire can clearly measure the current variation when the CO gas was added into the chamber.
Ku, Hung-Hsi, and 辜泓熙. "Direct growth of Mg-Fe-CO3 layered double hydroxide on pure Mg and its corrosion property in conventional simulated body fluid." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/xj2m2k.
Повний текст джерела國立中興大學
材料科學與工程學系所
100
Mg-Fe-CO3 layer double hydroxide (Mg-Fe-CO3 LDH) has been investigated that is highly biocompatible and is low cytotoxicity. LDH usually be synthesized into powder, and is utilized to be a drug delivery. This work presents a method for directly forming Mg-Fe-CO3 LDH on the pure Mg substrate and the coating of the Mg-Fe-CO3 LDH could increase the ability of corrosion-resistant in C-SBF at 37.5 。C. Moreover, the size of the platelet-like structure of Mg-Fe-CO3 LDH is affected by the pH value of the Fe3+/HCO3-/CO32- at 70 。C. the size of the platelet-like structure of Mg-Fe-CO3 LDH the CO2pH6.0/20h sample is bigger than the CO2pH4.6/20h sample. Repeatedly sliding on the CO2pH4.6/20h sample could be an effective way to change the morphology of the CO2pH4.6/20h sample. From the cross-sectional observation of the CO2pH4.6/20h sample by TEM, Mg-Fe-CO3 LDH (the top layer), the middle layer and inner layer were observed. The thickness of Mg-Fe-CO3 LDH is around 1um, the middle layer is around 2~2.5um and the inner layer is 1~2um. The Mg-Fe-CO3 LDH is composed of Mg, Fe, C and O. Moreover, the middle layer and the inner layer are composed of Mg, C and O.
Chen, Chieh-Hung, and 陳玠宏. "Direct growth of a soft-magnetic layer on pure Mg in aqueous Fe3+/HCO3-/CO32- bath." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/24185527566477524454.
Повний текст джерела國立中興大學
材料科學與工程學系所
99
In this study, an environmental friendly treatment of CO2 recycling was used to form a composite soft-magnetic layer on magnesium sample’s surface by chemical reaction in Fe3+/HCO3-/CO32- and pH 9.5 HCO3-/CO32- solutions. The layer was composed of soft magnetic iron particles and Mg-Fe-CO3 layered double hydroxides (Mg-Fe-CO3 LDH). The size and quantity of crystalline Fe can be raised by increasing immersing time of samples in the Fe3+/HCO3-/CO32- solution. And the soft magnetic property of the layer on Mg sample can also be enhanced. The Mg-Fe-CO3 LDH LDH layer played an important part in covering the Fe particles and enhancing the adhesion of the Fe particles on the sample surface. The thickness of the Mg-Fe-CO3 LDH layer is concerned with reaction time of sample in the pH 9.5 HCO3-/CO32- solutions. The quantity of the Mg-Fe-CO3 LDH on the sample surface would increase with prolonging treatment time in the pH 9.5 HCO3-/CO32- solution. The rolled magnesium samples present better soft magnetic property than the magnesium sample from as-cast ingot after these samples conducted by the same treatment. Based on the same treatment process, a rolled Mg sample could have better soft magnetic property that a casted Mg sample did.
Wei, Chao-ting, and 魏兆廷. "The ultrasonic attenuation study for dislocation, grainboundary and precipitates morphologies of pure aluminum and Al-Mg-Si alloy." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/38401299773378609816.
Повний текст джерела國立中央大學
機械工程研究所
99
The study used ultrasonic testing to obtain the attenuation of 99.999% pure aluminum and 6063 aluminum alloy. As the result, the measured attenuation is sensitively in varied dislocation density or dislocation loop, so that would increase the calculation errors. Furthermore, we measure attenuation and separate into two parts for discuss: i) grain boundaries set as ; The grain boundary on attenuation were divided to varied angle boundaries (low angle: 0 o ~ 5o, middle angle: 5 o ~ 15o, high angle: 15 o ~ 65o). The angle of grain boundaries of 5N pure Al was observed by using electron back scatter diffraction (EBSD), and estimated the relation between the grain boundary fractions and attenuation. And ii) matrix set as B value. The subtraction of the ultrasonic attenuation of high frequency and low frequency would increase the sensitivity of the difference of the attenuation. The change of grain size of annealed Al6063 by different cooling rate can observed from the subtraction of the ultrasonic attenuation. There are two stages were observed from the subtraction of the ultrasonic attenuation varying micro-hardness of Al6063 during T4 process (nature aging). One is the nucleation and growth of solute atoms (Mg-cluster、Si-cluster). The subtraction decreases with the increasing of the aging time. The other stage is the steady growth or coalescence of clusters. The changes of the subtraction and micro-hardness are unapparent.
Biswas, Somjeet. "Evolution Of Texture And MIcrostructure During Processing Of Pure Magnesium And The Magnesium Alloy AM30." Thesis, 2010. http://etd.iisc.ernet.in/handle/2005/1258.
Повний текст джерелаHuang, Yung-Sen, and 黃永森. "The study of the AAO film growth behavior on the pure Aluminum, and the electrochemical behavior of anodized Al-Mg-Si and Al-Zn-Mg-Cu aluminum alloy." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/83102731861572092462.
Повний текст джерела國立中央大學
機械工程學系
101
In recent years, aluminum alloys are widely used for making 3C products due to their lightweight, good mechanical properties and superior cosmetic appearance after anodizing. The purpose of this study is to introduce the anodization behavior of high purity aluminum and the qualities of anodized Al-Mg-Si and Al-Zn-Mg-Cu aluminum alloy with different matrix structures. The individual brief are as following: Gas bubbles formed during anodization of aluminum in sulfuric acid solution but no precise computation of bubbles size have been presented and discussed in literatures. In this study, we utilized X-ray photoelectron spectroscopy (XPS) to investigate the constituent phases of anodic alumina oxide that formed in a short anodization time. Amorphous alumina prevailed in the films together with a certain amount of hydrated alumina (Al(OH)3), oxyhydroxide (AlOOH) and alumina sulfate (Al2(SO4)3). A hydrophone was applied to measure the acoustic pressure field in the electrolyte during anodization. Experimental results indicated that acoustic pressure oscillated with appropriate frequency ranging from 50 Hz up to 500 Hz. A power spectrum density function (PSD) and cepstrum was adopted to analyze the signal of sound spectrum. The collapse and rebirth of gas bubbles on the surface of anodic aluminum oxide (AAO) film and/or at the pore bases oscillated the measured acoustic pressure. We found that the size of gas bubbles could range from 8 nm to 16 nm in diameter to corresponding to the detected oscillated frequency 400 to 50 Hz, respectively. A series of reactions occurred during anodization to yield SO3 gas and O2 gas, which collapsed and rebirth during the early-growth of AAO film. This study also intends to investigate the effect of deformation on varying the matrix of 6063 and 7075 alloy and on the quality of anodized aluminum oxide film.The Al-Mg-Si alloy and Al-Zn-Mg-Cu contains about 0.6 %Mg and 0.4%Si and Al- 5.4 wt% Zn- 2.5 wt% Mg- 1.5 wt% Cu are a heat treatable alloy with precipitation hardening. Different degree of deformation would be introduced to simulate the forming process in making parts resulting in varying effects on the precipitation hardening of matrix. The highest dislocation density was observed in the SCRT6 sample which also showed the lowest inclusion particle numbers among the three Al-Mg-Si samples. The sample that has been subject to the cryo-rolling process prior to rolling and heat treatment showed few subgrains and smaller amounts of second phase particles in the matrix than was the case with the other two sets of Al-Zn-Mg-Cu samples. Subsequently, all samples were anodized in a 15 wt % sulfuric acid solution for different time spans to obtain different state of AAO films. The anodized samples were further analyzed and observed with Field emission scanning electron microscope (FE-SEM), Transmission electron microscopy (TEM), Atomic force microscopy (AFM) and Electrochemical impedance spectroscopy (EIS) and potential-dynamic polarization curve (PD-curve) analysis. We determined that the constituent phases in the AAO film were composed of hydrated amorphous alumina, hydrated oxide (Al(OH)3) and oxyhydroxide (AlOOH) phases together with some silicon-containing particles trapped in the films on Al-Mg-Si samples. The matrix of Al-Zn-Mg-Cu alloy contained the disc-like precipitates of Mg2Zn and Al2Cu and dissolved from the matrix during anodizatione and remained tiny air-pockets in the AAO film. In the potential-dynamic polarization test, the silicon-containing particles and tiny air-pockets that existed in the AAO films were found to inversely influence the corrosion resistance of the anodized samples.
HsienChingChen and 陳憲清. "Effects of ball milling with C、Ag、Pd、Pt and Zr on the hydrogen storage performance of pure Mg." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/fkhh6p.
Повний текст джерела逢甲大學
材料科學與工程學系
104
The hydrogen storage capacity of pure magnesium with adding various amounts of active carbon by ball milling was investigated in this study. To compare with the hydrogen storage performance of ZK60 alloy, the related properties of pure magnesium with adding 5 wt% active carbon and various amounts of Ag、Pd、Pt、Zr and Nb by ball-milling for 20 hours were also studied. Experimental results showed that the pure magnesium with 15wt% C has the best hydrogen storage capacity of 6.62 wt%. Then it decreases with increasing the amount of active carbon. For pure magnesium with 5 wt% C, the hydrogen storage capacity can reach 5.00 wt%. In the study of pure magnesium with adding various kinds of catalyst elements, the hydrogen storage capacity of Mg with 5C and 0.5Ag can reach 5.71 wt% at 360℃, and it becomes 6.81 wt% for Mg with 5C and 0.5Pd at the same absorption/desorption temperature. The hydrogen storage capacities of Mg5C0.7Zr and Mg5C0.7Pt are 5.83 wt% and 5.59 wt%, respectively, at 360℃. It is noted that the catalytic effect is obvious for Mg with adding Pd, and the hydrogen storage speed is significant for Mg with adding Zr. In the study of Mg with adding 5C and various amounts of Nb, the hydrogen storage capacity of Mg with 5C and 0.5Nb reaches the maximum value of 5.78 at 360℃, and it exhibits excellent cyclic stability for Mg with 5C0.5Nb. However, the hydrogen storage capacity of Mg with 5C0.5Nb is not so good at 320℃ and 340℃, and it becomes less than 2 wt% after the first cycle at these temperatures. The hydrogen storage performance of Mg5C1Nb and Mg5C1.5Nb is worse than that of Mg5C0.5Nb. For comparison between Mg and ZK60 with adding 5C and various amounts of Ag、Pd and Zr, the hydrogen storage capacity of Mg 5C0.5Pd is 6.81 wt% at 360℃, which is higher than 6.33 wt% for ZK605C0.5Pd at the same temperature, due to the significant catalytic effect for Mg with adding Pd. The effect of adding Ag、Pd and Zr on the hydrogen storage speed is more obvious for ZK60 than that for Mg. The hydrogen storage capacity of ZK60 for absorbing hydrogen at the first five minutes is about 95% of that for 60 minutes, and it is about 90% for Mg at the same conditions.