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Abstract:Current research activities on the fatigue of ferroelectric ceramics are reviewed. Research progress in the fatigue mechanism, factors which influence fatigue behavior, and experimental techniques employed in the study of the fatigue are summarized. Various mechanisms for electric fatigue and different models of the electric-field-induced fatigue process are compared and discussed. Problems that need to be solved and clarified in order to gain a deep insight of fatigue mechanism are suggested.

Abstract:The structural characteristics and electrochemical processing of LiFePO4 for lithium ion battery anodes are discussed. LiFePO4 is characterized by high specific capacity and good cycle performance, But its dielectric property and low diffusion coefficient being not sufficiently well known at present restict its application to small batteries at present. It is concluded that LiFePO4 powder with high electrochemical performance can be fabricated using proper fabrication and surface modification procedures. This powder: with its environmentally benign properties, low cost, and abundance, is a promising alternative for lithium ion battery anodes.

Abstract:The research development and the main methods used in performance improvement of Mg2Ni-type hydrogen storage alloys are summarized. It is suggested that nanocrystallization or amorphization, composition adjustment and modification by compounding is the best ways to improve the performance indices of the alloys.

Abstract:報(bào)道了從水溶液中電沉積稀上含量高于30％的Ni-RE-P(RE=Ce，Nd)合金，其中Ni-P，Ni-Ce-P及Ni-Nd-P合金鍍層均為非晶態(tài)結(jié)構(gòu)，玻璃化溫度約為385℃；用DTA測(cè)定了3種合金的晶化活化能分別為：523．3kJ／mol，574．4kJ／mol，558．9kJ／mol；利用二維Miedema坐標(biāo)(△φ^*和△nws^-1.3)以及加入尺寸因素(△R/RA)構(gòu)成的三維化學(xué)坐標(biāo)分析了合金的非晶形成規(guī)律，探討了實(shí)現(xiàn)稀土合金電沉積的途徑，具體為：選擇適當(dāng)?shù)慕j(luò)合劑、合適的電極材料及合適的共沉積元素。

Abstract:The thermodynamic requirements of internal oxidation of Cu-Al alloy were systematically analyzed, and a zone chart of internal oxidation thermodynamics was drawn. The results indicate that the preferential oxidation zone is quite large in the zone chart, and is determined by the maximum and minimum partial pressure of oxygen, where=(max)O2lgP(17 611/T)+12.91,=(min)O2lgP (55 830/T)(4/3)lg[%Al]+19.95. In fact the practical internal oxidation zone is a small part of the preferential oxidation zone near the maximum partial pressure of oxygen. The volume concentration product Ksp and concentration of residual aluminum are so low that the internal oxidation can procede completely. The temperature and partial pressure of oxygen should be adjusted synchronously during the control of internal oxidation. The optimum conditions for internal oxidation are heat treatment at a high temperature of about 1 223 K, and a high oxygen partial pressure approaching or even equal to the upper limit. Rapid cooling with hydrogen is used to prevent oxidation of the copper.

Abstract:The effects of the Ce content on the structure, thermodynamics, electrochemical properties and kinetic performance of the AB5-type hydrogen storage alloys La0.8(1-x)Ce0.8x(PrNd)0.2B5 have been systematically studied. The results show that, the Ce content dependence of the alloy structure is negligible, though the cell parameters a, c and the cell volume change linearly with Ce content. With the increase of the Ce content, the equilibrium pressure for hydrogen absorbing-desorbing of the alloys increases, the hysteresis gets smaller, and the thermodynamic stability of alloy hydride becomes poorer. The Ce content has a little effect on the electrochemical activation property of the alloys, its increase could raise the charge-discharge voltage plateau of the alloys, could improve the high-rate discharge ability and power characteristics of the alloys, while the discharge capacity at low discharge current is decreased. The increase of the Ce content is beneficial to improving kinetic performance of the alloys, it could decrease charge transfer resistance of the electrode reaction and make it more reversible. Hydrogen in the alloys diffuses faster with the increase of the Ce content.

Abstract:Cu, Ag and the Ni films on stainless steel bases and Ni film on Ti substrates are prepared by using electroplating. The cantilever beam method and X ray diffraction are used to measure the internal stresses in the films. Internal stresses caused by interfacial electron transfer are also calculated using the modified TFD model. It is shown that the calculated results are comparable with those of the experiments, indicating that the main source of the internal stress in the films is the interfacial electron transfer.

Abstract:The Potential-pH diagrams of the Zr-H2O system at temperatures of 298 K, 333 K, 373 K and 423 K were be established through extensive study of thermodynamic data and thermodynamic calculation coupled with experimental results? The Potential-pH diagram at 298 K concides with that at the same temperature drawn by Professor M.Pourbaix. Comparing and analyzing potential-pH diagrams of Zr-H2O system at different temperatures, it is evident that with the temperature increasing there is no great change of the immunity area of zirconium, but remarkable reduction of the passivation area, which theoretically accounts for the high temperature limitation of zirconium.

Abstract:The tribological properties of Ni-Cr-CaF2 as well as Ni-Cr-PbO/Si3N4 tribo-couples were investigated. The transferring behavior of solid lubricants at the interface of Ni-Cr alloy/Si3N4 tribo-couples were analyzed by scanning electron microscopy. The results showed a significant presence of CaF2 on the Si3N4 surface, while a completely transferred Pb film was not found on the Si3N4 surface due to its poor wetting capability on Si3N4.

Abstract:研究了回歸溫度(180℃，200℃，220℃)及預(yù)時(shí)效時(shí)間(12h，18h，24h)對(duì)含Ag的7055鋁合金回歸再時(shí)效后的強(qiáng)度和微觀組織的影響。結(jié)果表明，由于微量Ag的添加，120℃，l8h預(yù)時(shí)效處理后180℃回歸再時(shí)效的強(qiáng)度穩(wěn)定性較高，而隨著回歸溫度的提高，再時(shí)效強(qiáng)度下降較快，這種現(xiàn)象歸因于Ag的添加提高了GP區(qū)和η′相的穩(wěn)定性，使得GP區(qū)溶解溫度升高，因而180℃回歸時(shí)只發(fā)生GP區(qū)和η′相的緩慢粗化，而200℃和220℃回歸時(shí)發(fā)生GP區(qū)的溶解并促進(jìn)，η′相快速粗化形成η相；實(shí)驗(yàn)結(jié)果顯示，預(yù)時(shí)效時(shí)間對(duì)回歸再時(shí)效后的強(qiáng)度也有較大的影響：預(yù)時(shí)效時(shí)間較長(zhǎng)或較短時(shí)(12h，24h)，再時(shí)效強(qiáng)度隨回歸時(shí)間的變化較大，而經(jīng)18h預(yù)時(shí)效，再時(shí)效強(qiáng)度穩(wěn)定性較高。這種差別是由于預(yù)時(shí)效后析出相的種類和體積分?jǐn)?shù)不同所致。

Abstract:采用電化學(xué)測(cè)試技術(shù)研究了Ce對(duì)新研制的口腔用Ti-Fe-Mo-Mn-Nb-Zr合金在人工體液中耐腐蝕性能影響，采用浸泡試驗(yàn)探討了Ce對(duì)Ti-Fe-Mo-Mn-Nb-Zr合金在不同pH值乳酸中耐腐蝕性能的影響。研究表明，含Ce與不含Ce的合金在Hank’s人工模擬體液浸泡的自腐蝕電位均高于0．42V，且隨Ce加入量的增加合金的自腐蝕電位先降低再升高然后再降低；Ce的加入沒(méi)有改變合會(huì)的陽(yáng)極化曲線類型，均為典型的鈍化類型陽(yáng)極化；Ce的加入使合金在乳酸中的腐蝕由點(diǎn)蝕轉(zhuǎn)變?yōu)辄c(diǎn)蝕和晶界腐蝕；原子發(fā)射光譜(ICP)分析表明隨乳酸酸性增強(qiáng)，含Ce與不含Ce合金的耐腐蝕性能差異增大；Ce的加入不利于提高該材料在人工體液和乳酸中的耐腐蝕性能。如果為了提高合金力學(xué)性能，Ce的最佳加入量為0．1％(按質(zhì)量）。

Abstract:將Zr-4合金樣品分別放在盛有350℃，0．1mol／L的LiOH和KOH水溶液的高壓釜中進(jìn)行腐蝕，當(dāng)2種樣品的氧化膜厚度相同時(shí)，用二次離子質(zhì)譜儀(SIMS)測(cè)量Li^ ,K^ 和OH^-在氧化膜剖面上的濃度分布，發(fā)現(xiàn)進(jìn)入氧化膜的Li^ 比K^ 深而且記數(shù)強(qiáng)度高，同時(shí)在LiOH水溶液中腐蝕的樣品，其氧化膜中OH^-的強(qiáng)度也比在KOH水溶液中腐蝕的樣品高，這表明OH^-在氧化膜中的分布和擴(kuò)散與其對(duì)應(yīng)的陽(yáng)離子有關(guān)。根據(jù)以上結(jié)果討論了Zr-4合金在LiOH水溶液中耐腐蝕性能降低的原因。

Abstract:The segregation of Ti-2.5Cu, Ti-3Fe and Ti-3Cr, in Ti-alloy ingots has been studied. It was found that in equiaxed grains, segregation of Cu and Fe is obvious and segregation of Cr is slight. In columnar grains, segregation of Cu, Fe, and Cr is slight. In both cases the contents of Cu, Fe, and Cr increase along the directions of grain growing. It is rich in Cu and Fe in grains; but it is rich in Cr at grain boundaries. In the bulk it is rich in Cu, Fe and Cr on the top and radial zone of the ingots.

Abstract:采用固定床化學(xué)氣相法存800℃碳化納米α-W粉體制備成功晶粒尺寸為15nm左右的納米WC粉體。用XRD分析測(cè)量了不同退火溫度下納米WC的晶粒尺寸。結(jié)果表明，隨著退火溫度升高，納米WC粉體的晶粒尺寸隨之增大，從原始晶粒尺寸15nm長(zhǎng)大到1500℃時(shí)的47nm。同時(shí)在不同升溫速率下測(cè)量納米WC粉體的DSC曲線，并由Kissinger方程求得其晶粒長(zhǎng)大激活能為3．494eV。

Abstract:用工業(yè)型脈沖等離子體增強(qiáng)化學(xué)氣相沉積設(shè)備，在550℃的高速鋼基材表面沉積由納米晶TiN，納米非晶Si3N4以及納米或非晶TiSi2組成的復(fù)相薄膜。通過(guò)改變氯化物混合比例調(diào)節(jié)薄膜的成分。薄膜中的Si含量在0at％～35at％范圍內(nèi)變化。結(jié)果表明，當(dāng)加入少量Si元素后，由于非晶相的產(chǎn)生，TiN薄膜的耐腐蝕性能顯著提高，并在一定Si含量的薄膜中發(fā)生了負(fù)腐蝕現(xiàn)象。但由T-Si的低導(dǎo)電性能，致使高硅含量薄膜顆粒粗大，因此更高Si含量薄膜的耐腐蝕性能又有所下降。

Abstract:采用Si3N4和SiC作為Al2O3／BN可加工陶瓷的添加劑，考察了添加劑種類和含量對(duì)材料力學(xué)性能及可加工性能的影響。研究表明，2種添加劑均對(duì)調(diào)節(jié)體系中由于熱膨脹失配所引起的人的內(nèi)應(yīng)力起到積極的作用。材料的抗彎曲強(qiáng)度隨添加劑含量的增加而提高，同時(shí)可加工性能略有降低。尤其是Si3N4的加入使體系在熱壓燒結(jié)過(guò)程中原位反應(yīng)生成液相x-Sialon，顯著降低了燒結(jié)溫度，促進(jìn)材料的致密化。

Abstract:通過(guò)對(duì)樣品壓敏性能和介電性能的測(cè)定，研究了CeO2對(duì)Nb-TiO2電容-壓敏電阻器的影響。研究發(fā)現(xiàn)，晶界處硅鈦酸鈰相的生成使Ce02對(duì)Nb-TiO2電容-壓敏電阻的性能有顯著的影響。在1350℃燒結(jié)條件下，摻雜量為0．4m01％CeO2的樣品表現(xiàn)出優(yōu)良的綜合電性能，其壓敏電壓為15．84V／mm，非線性系數(shù)α為4．62，并具有很高的相對(duì)介電常數(shù)(εγ=158600)，較低的介電損耗(tgδ=0．32)，是1種具有較好潛力的新型電容-壓敏電阻器。

Abstract:TiO2 thin films were prepared on microscope glass slides by radiofrequency magnetron sputtering method under different flow ratios of Ar and O2 gases. The films were characterized by X-ray diffraction (XRD), atomic force microscope (AFM), Raman spectroscopy and UV-VIS spectrophotometer. The results indicated that the film prepared under the flow ratio of ArO2=20 sccm5 sccm has a higher photocatalytic activity.

Abstract:In order to prevent the agglomeration and improve the dispersion of ultrafine ceramic powders in liquid paraffin system etc. organic media, different kinds of polymer films were coated on the surface of ultrafine ZrO2 and SiC particles by low temperature plasma polymerization. The encapsulated powders were analyzed by TEM, TGA, and DRIFT. The results show that, the dispersion of plasma treated ZrO2 powders in the organic medium was better than that of untreated ZrO2 powders. The viscosity of liquid paraffin with same solid loading showed a significant difference between plasma treated and untreated ceramic powders.

Abstract:研究了SmCo薄膜的復(fù)合及熱處理對(duì)TbDyFe薄膜磁性及磁致伸縮性能的影響。XRD分析表明制備態(tài)的TbDyFe薄膜為非晶態(tài)，在450℃退火后，樣品仍保持非晶態(tài)結(jié)構(gòu)。退火處理減少了薄膜的垂直各向異性，并且退火熱應(yīng)力有利薄膜的易磁化軸轉(zhuǎn)向膜面，從而提高了薄膜的磁導(dǎo)率和TbDyFe薄膜低場(chǎng)下的磁致伸縮值。磁控濺射的SmCo薄膜有良好的軟磁性能，它的復(fù)合也能有效地增強(qiáng)TbDyFe薄膜的低場(chǎng)磁致伸縮性能。

Abstract:In this paper TiB2 coating was electrodeposited on the graphite by K2TiF6-KBF4-KF-KCl molten salts. The effects of pre-electrolysis conditions and electroactive component contents on the properties of coating were tested. The results showed that: pre-electrolysis conditions had important effect on the compositions of coating; as the mole ratio of K2TiF6 and KBF4is 1:2.5 with higher total content of K2TiF6-KBF4, the coating had better adhension to the substrate and the process had good repetition, but the crystal particle was large and the coating has less impurity; as the mole ratio of K2TiF6 and KBF4is 1:7.5 with lower total content of K2TiF6- KBF4, the coating had fine crystal particle and higher TiB2 content with metallic gloss, but the process had bad repetition. Further electrochemistry experiments need to be done to find the mechanism and stable conditions for electrodepositing of TiB2 coating.

Abstract:Using a commercially available alloy such as BNi2 which contains the active elements Ti and Cr, and a self-made CuSnNiTi alloy as an active filler materials, a monolayer brazing diamond grinding wheel has been made in a vacuum furnace. Using thermal analysis (DSC) and EDX, it was shown that at appropriate an brazing temperature, duration and vacuum level, chemical bonding takes place among the diamond, brazing alloy and substrate, and that different bonding strengths and performance accompany the use of various brazing filler alloys. Since CuSnNiTi alloy wets the diamond surface, the brazing temperature can be reduced and the bond strength can be enhanced greatly. Grinding tests show that the matrix with this particular filler strongly retains the diamond, and that the cutting efficiency is increased at constant cutting life.

Abstract:用輪番濺射工藝在多靶磁控濺射設(shè)備上制備了SmCo薄膜。通過(guò)改變Sm，Co純金屬靶的濺射時(shí)間間隔和濺射功率來(lái)調(diào)整薄膜的化學(xué)成分和均勻性。實(shí)驗(yàn)表明，可以通過(guò)調(diào)整濺射電流來(lái)優(yōu)化薄膜的化學(xué)成分。沿垂直膜面俄歇電子(AES)逐層分析證明，優(yōu)化濺射工藝制備的薄膜化學(xué)成分分布均勻。電子衍射表明薄膜濺射態(tài)為非晶結(jié)構(gòu)，經(jīng)過(guò)400℃退火處理，薄膜開(kāi)始晶化。VSM分析表明濺射態(tài)的薄膜為軟磁特征。晶化后的薄膜表現(xiàn)為硬磁特征，450℃退火時(shí)薄膜的矯頑力最大，達(dá)80320A／m。薄膜呈現(xiàn)一定的各向異性。

Abstract:A misch-metal hydrogen-storage alloy consisting of a homogenous CaCu5 phase with grain size less than 50 nm was prepared by rapid quenching between double rollers. The specific capacity of alloy reached 295 mAh/g during charge and discharge with 200 mA/g. The attenuation of capacity was 4.5% after 200 cycles. The charging capacity of a battery made from this alloy powder was up to 547.4 mAh/g after 2 cycles discharge with a Couloumb. The attenuation of capacity was 2.48% after 95 cycles.

Abstract:為解決銀材自然時(shí)效軟化的問(wèn)題，存99．999％Ag中添加0.004％A1和0．003％Mn(按質(zhì)量)制成純度為99．99％的Ag材，實(shí)驗(yàn)表明，采用變形率為90．90％所制備的銀材，在25℃溫度下，自然時(shí)效365d，其強(qiáng)度σb=370MPa，硬度HV=1030MPa保持穩(wěn)定不變，有效地抑制了純銀材自然時(shí)效80d，其力學(xué)性能便大幅度下降的問(wèn)題。