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Abstract:采用循環(huán)伏安法和計(jì)時(shí)電流法研究了700℃時(shí)LiF-NaF-KF-K2TiF6熔鹽中Ti(IV)在鉑電極上陰極電化學(xué)還原機(jī)理以及電結(jié)晶過程。結(jié)果表明:Ti(IV)的電化學(xué)還原機(jī)理為三步驟電荷傳遞反應(yīng):Ti(IV)+e→Ti(III);Ti(III)+2e→Ti(I);Ti(I)+e→Ti(0),且陰極過程可逆;電結(jié)晶過程為瞬時(shí)形核。

Abstract:采用熱模擬壓縮試驗(yàn)研究了Ti-40阻燃鈦合金在溫度900℃～1100℃、應(yīng)變速率0．01s^-1～10s^-1范圍內(nèi)的高溫變形特性，發(fā)現(xiàn)合金的流動(dòng)應(yīng)力-應(yīng)變曲線具訂應(yīng)力峰和流變軟化特征，在高溫、高應(yīng)變速率下，出現(xiàn)小連續(xù)屈服現(xiàn)象。根據(jù)動(dòng)態(tài)材料模型（DMM）建立的Ti-40合金加工圖大致可以分為5個(gè)區(qū)域：（1）在溫度900℃-950℃，應(yīng)變速率大于1s。時(shí)，易發(fā)生45°角剪切開裂，出現(xiàn)明顯的剪切變形帶，功率耗散率達(dá)最小值。（2）在溫度1000℃～1100℃、應(yīng)變速率人于1s^-1時(shí)，易出現(xiàn)“豆腐渣”式和縱向開裂，大變形時(shí)出現(xiàn)局部塑性流動(dòng)。這2個(gè)區(qū)域?yàn)榱鲃?dòng)失穩(wěn)區(qū)，在制定熱加工工藝時(shí)應(yīng)盡量避免。（3）在高溫（≥1050℃）、低應(yīng)變速率區(qū)（≤0．1s^-1），功率耗散率為46％-76％，達(dá)到盛大值，呈現(xiàn)連續(xù)冉結(jié)晶的特征。（4）在900℃-950℃、應(yīng)變速率0．01s^-1～0．1s^-1區(qū)域內(nèi)主要發(fā)生動(dòng)態(tài)回復(fù)，功率耗散率為22％-32％。（5）在溫度950℃～1050℃、應(yīng)變速率0.1s^-1～1s^-1范用為再結(jié)晶區(qū)域，功率耗散率為36％～50％。結(jié)果表明，加工圖是控制材料組織演變和優(yōu)化工藝的一種有效手段。

Abstract:以TiN和NiCrBSi合金混合粉末為原料，采用激光熔覆技術(shù)在TC4合金表面制備出TiN顆粒增強(qiáng)Ni基合金涂層。利用XRD，SEM和TEM等分析了激光熔覆層的相組成及微觀組織，并測(cè)試了激光熔覆層的顯微硬度和磨損性能。結(jié)果表明，激光熔覆層由熔覆區(qū)和稀釋區(qū)2個(gè)區(qū)域組成，熔覆區(qū)的組織是在γ-Ni樹枝晶和γ-Ni＋Ni3B層片狀共晶的基體上均勻地分布著TiN顆粒和針狀尬3C6相，顯微硬度在9000MPa-12000MPa之間.稀釋區(qū)為基底TC4合金和熔覆材料Ni基合金的混合凝固區(qū)，呈胞狀晶和樹枝晶形態(tài)。激光熔覆層中存在顆粒強(qiáng)化、細(xì)晶強(qiáng)化和固溶強(qiáng)化等多種強(qiáng)化作用，大幅度地提高了TC4合金的耐磨性能。

Abstract:研究了工業(yè)純鈦TA2室溫下蠕變第1階段的特性。結(jié)果表明，TA2材料室溫下確實(shí)存在明顯的蠕變現(xiàn)象，并且存在一個(gè)臨界應(yīng)力值，低于該臨界值的TA2在室溫下不會(huì)發(fā)生蠕變。TA2室溫下蠕變第1階段的規(guī)律為盧蠕變。針對(duì)TA2材料室溫下第1階段的蠕變特性，本研究提出了一種新的盧值與應(yīng)力間的關(guān)系表達(dá)式：β=β0（σ-σ）c^m。其中σc。為蠕變臨界應(yīng)力。并且得到室溫下TA2的蠕變臨界應(yīng)力值為267．25MPa。

Abstract:To understand the characteristics of extruded, forged and annealed tantalum(Ta), the chemical composition, hardness and microstructure of Ta in each working process are measured. Mechanical performance of Ta after each working process was studied. The thermomechanical responses of forged and annealed Ta were investigated at different temperatures and different strain rates, using Instron servohydraulic testing machine and the split Hopkinson compression bar. Results show: (1) elements O and C in as-extruded Ta were 30% higher than those in Ta powder, but element of N was 50% lower than that of powder; (2) as-extruded Ta was forged and annealed at 1523 K for 2 h, complete recrystalization occured. Grain number and hardness of Ta disk changed from center to edge; (3) the mechanical performance in certer of the Ta disk showed remarkably anisotropy, this phenomenon appeared slightly at edge of the disk. Finally, Based on mechanism of thermal activation glide of dislocation, and physical concept of plastic deformation, a constitutive modeling was deduced to predict palstic flow stress of Ta. Modeling results were compared with the results of Johnson-Cook modeling and experimental results. The results show that the present dynamic constitutive modeling can make a satisified predication to the plastic flow seress.

Abstract:In order to increase the density of W-Ni-Mn alloy, some alloying elements were added into W-Ni-Mn alloy for improving sintering characteristics. SEM and EDS were used to study the microstructure of sintered W-Ni-Mn alloy. The results show that MnO can be deoxidized by aluminum and silicon, to purify the binder phase;Zn and Sn can reduce the sintering temperature. The two approaches improve the density of W-Ni-Mn alloy.

Abstract:以SmCl3為原料，硼氫化鈉為還原劑，低代（2．0G3．0G,4．0G）PAMAM樹形分子為模板兼穩(wěn)定劑、制備出納米顆粒。實(shí)驗(yàn)發(fā)現(xiàn)，其他條件相同時(shí)，樹形分子代數(shù)越高，所起的模板作用越顯著，即Sm／4．0GPAMAM的復(fù)合納米顆粒粒度均勻，分散度好。應(yīng)用Virtual Materiale（VM）軟件對(duì)Sm／PAMAM納米顆粒進(jìn)行分子動(dòng)力學(xué)模擬。從分子結(jié)構(gòu)和能量變化角度研究了正則（恒定的NVT）系中復(fù)合體系的穩(wěn)定性及其機(jī)理。分子動(dòng)力學(xué)模擬結(jié)果顯示：4．0GPAMAM更適合于作為模板劑和穩(wěn)定劑，表明動(dòng)力學(xué)模擬結(jié)論與實(shí)驗(yàn)結(jié)果一致。

Abstract:以鍛造CoNiCrMo，CoCrMo和CoCrMoC臺(tái)會(huì)為研究對(duì)象，通過金相觀察，XRD分析和耐腐蝕試驗(yàn)，研究了3組合金在不同熱處理?xiàng)l件下的顯微結(jié)構(gòu)，相成分及在Hi同溶液中的耐腐蝕性能。結(jié)果表明：2組鍛造合金的再結(jié)晶溫度都是1000℃，且晶粒尺寸隨著固溶溫度升高和時(shí)效時(shí)間延長(zhǎng)而逐漸變大。3組試樣在NaCl溶液中為鈷基合金典型的陽(yáng)極極化曲線；在Hanks’溶液中均有一個(gè)二次鈍化行為，且鍛造CoNiCrMo合金的二次鈍化區(qū)域較窄，而其他2組合金則較寬；在含檸檬酸三鈉的溶液中過鈍化電位降低，檸檬酸鹽的存在降低了含金的耐腐蝕性能。熱處理對(duì)合金的耐腐蝕性能影響不大。

Abstract:研究了K465高溫合金在850℃←→20℃,950℃←→20℃，1000℃←→20℃和1050℃←→20℃←冷熱循環(huán)過程中碳化物的析出情況。在850℃←→20℃冷熱循環(huán)過程中，沒有發(fā)現(xiàn)析出犁碳化物；在950℃←→20℃冷熱循環(huán)過程中，在枝晶間析出了M6C碳化物；在1000℃←→20℃和1050℃←→20℃冷熱循環(huán)過程中，在枝晶間和枝晶千同時(shí)析出了方塊狀、短桿狀、顆粒狀和針狀M6C碳化物。與等溫?zé)崽幚硐啾?，冷熱循環(huán)作用明顯促進(jìn)M6C碳化物的析出。此外，提高冷熱循環(huán)的上限溫度加速M(fèi)6C碳化物的析出。

Abstract:通過對(duì)一種單晶鎳基合金的差熱曲線分析和不同條件熱處理后的組織形貌觀察，結(jié)合有限元分析，研究了合金中‘γ’相在熱處理期間的組織演化規(guī)律。結(jié)果表明：實(shí)驗(yàn)用合金的熱處理‘窗口’是48℃，在1300℃γ，相有最大的溶解速度，1040℃析出的γ’相最為穩(wěn)定；確定出該合金的熱處理工藝為1280℃，4h，AC＋1300℃，4h，AC＋1040℃，4h，AC＋870℃．24h,AC.一次時(shí)效期間，在界面能和共格應(yīng)變能的作用下，γ’相長(zhǎng)大呈立方體形貌；二次時(shí)效期間。γ’相略有長(zhǎng)大，立方度增加，排列更加規(guī)則。其中，時(shí)效期間，共格界面的γ’相按“臺(tái)階機(jī)制”優(yōu)先沿（100）取向擴(kuò)散生長(zhǎng)呈立方體形貌，而晶格錯(cuò)配應(yīng)力的對(duì)稱分布是使立方γ’相得以穩(wěn)定存在的主要原因。

Abstract:采用Gleeble熱模擬機(jī)研究了預(yù)設(shè)升溫速度對(duì)Fe-V-C體系在電場(chǎng)作甩下燃燒合成的影響。用X射線衍射儀（XRD）以及掃描電鏡（SEM）等研究了試樣在不同預(yù)設(shè)升溫速度下的相結(jié)構(gòu)和顯微組織。結(jié)果表明：在電場(chǎng)作用下，該體系的反應(yīng)起始溫度較低。預(yù)設(shè)升溫速度對(duì)體系的影響呈階段變化，當(dāng)預(yù)設(shè)升溫速度為600℃／s-1000℃／s時(shí)，合成過程以及合成產(chǎn)物的變化不大：當(dāng)預(yù)設(shè)升溫速度升至1400℃／s時(shí)，體系的點(diǎn)火溫度降低、點(diǎn)火延遲時(shí)間縮短，合成產(chǎn)物顆粒變小，硬度提高。

Abstract:The static magnetic characteristics and microstructures of FeCuNbSiB fibres fabricated by the melt spun process, have been studied in this paper. The electromagnetic parameters (relative complex permittivity and permeability) of the composite have been also investigated using fibres heat treated at 673 K for 1 h in X band (8.2 GHz~12.4 GHz). In the range of 2 GHz~4 GHz, the effect of the content of the randomly oriented fibres in the composites (fibres + spherical magnetic particles + epoxy) on the electromagnetic parameters has been studied. The results show that the electromagnetic parameters can be improved effectively with an appropriate content of FeCuNbSiB fibres.

Abstract:借助光學(xué)顯微鏡、掃描電鏡、X射線衍射儀和萬(wàn)能拉伸測(cè)試儀研究了AM60合金中加入RE和B后的組織和性能，并分析了RE和B對(duì)合金組織和性能的影響。結(jié)果表明，RE和B都可以使合金的晶粒細(xì)化。蘆相的分布也變得均勻彌散，顯著改善合金的顯微組織，B和RE的同時(shí)加入效果最佳。0.15％（質(zhì)量分?jǐn)?shù)，下同）B加入AM60合金中沒有形成新相，1．6％的RE加入則形成了穩(wěn)定性較高的針狀A(yù)l11RE3等相，B的變質(zhì)作用及適當(dāng)?shù)闹苋芴幚砟苁贯槧畹南⊥料噔g化并變短。同時(shí)加入RE，B使合金的力學(xué)性能得到較顯著的改善，其中顯微硬度提高了26％，抗拉強(qiáng)度提高了20％。

Abstract:By using a Scanning Electron Microscope (SEM), the tracks of cathode spots on the surface of nanocrystalline Cu cathode produced after the first discharge with peak current of 10 A was investigated. It is found that the movement of cathode spots is sub-directed rather than random. The reason is explained in comparison with conventional Cu. It is suggested that sub-directed walking of cathode spots on the surface of nanocrystalline Cu is beneficial to the diffusion of cathode spots which is responsible for cathode erosion.

Abstract:利用電化學(xué)極化曲線和阻抗圖譜（EIS）技術(shù)研究了Pr60Fe30Al10塊體非晶及其晶化后合金在不同pH值的3．5％（質(zhì)量分?jǐn)?shù)，下同）NaCl溶液中的腐蝕行為。結(jié)果發(fā)現(xiàn)，隨著pH值的增大2種合金的耐蝕性都增強(qiáng)。即在開路電位Ecorr下，腐蝕電流icorr減小，Ecorr向貴金屬方向變化，極化電阻Rp及相應(yīng)的阻抗圖譜等效電阻R＇p增大；當(dāng)pH值一定時(shí)，非晶合金和晶化后臺(tái)金相比，非晶合金的陽(yáng)極極化曲線出現(xiàn)了寬的鈍化區(qū)，EIS Nyquist圖譜呈現(xiàn)出更大的容抗弧幅值，從而表現(xiàn)出強(qiáng)的耐蝕性。由極化曲線和交流阻抗技術(shù)所得到的極化電阻及腐蝕電流具有很好的一致性。

Abstract:Amorphous nickel hydroxide powder was prepared successfully by the method of micro emulsion deepfreeze deposition. Using tiny electrode of sample powder as researching electrode, Pt as assistant electrode and Hg-HgO as referenced electrode, we tested the polarization curve of amorphous Ni(OH)2 powder and calculated j0 and jd. The resalt showed that the number of electron exchange on charging and discharging was 1.35 according to our approximate calculation, and its theoretical discharge capacity was 393.26 mAh/g, so it has high electrochemical capacity.

Abstract:Through analysis of the hydriding/dehydriding process of hydrogen storage material, an apparatus for measuring hydrogen storage properties was designed and set up. This apparatus can be employed to measure the curves of the hydriding/dehydriding dynamics, the PCT curves and the cycle life for hydrogen storage material. The hydriding/dehydriding properties of LaNis was acquired by this apparatus. The result indicates that this design principle of apparatus is reasonable; LaNi5 has excellent hydriding kinetics properties however, the cycle life is rather bad because of quite fast capacity decrease after 60 ab-/desorption cycles.

Abstract:研究了氕和氘在Pd-8％Y（原子分?jǐn)?shù)，下同）合金膜中的滲透性能，預(yù)測(cè)了一定條件下以該合金管為分離膜材料的鈀合金膜分離器對(duì)氕和氘的分離性能。結(jié)果表明：在573K-873K，0．0SMPa-0．40MPa下，氕和氘的滲透通量與壓力的平方根成正比，氕和氘的滲透率與溫度之間滿足阿倫尼烏斯公式；滲透通量與壓力數(shù)據(jù)J=ФAmP^n/tm擬合時(shí)。n在0.66左右，表明對(duì)于裝置所用厚度的鈀合金膜。表面過程對(duì)氕和氘的滲透率有很大影響；在該溫度和壓力范圍內(nèi)，如果忽略同位素之間的相互作用，鈀合金膜分離器對(duì)1：1的氕和氘的分離系數(shù)在1，45～1．76之間，分離系數(shù)隨溫度的增高而減小。

Abstract:利用直流磁控濺射方法在柔性聚酯薄膜襯底上制備了氧化銦錫（ITO）透明導(dǎo)電薄膜，采用X射線衍射、紫外．可見分光光度計(jì)、四探針電阻測(cè)量?jī)x等測(cè)試手段對(duì)薄膜樣品進(jìn)行表征，研究了氧含量、薄膜厚度、村底負(fù)偏壓對(duì)ITO薄膜的晶體結(jié)構(gòu)和光電性能的影響，優(yōu)化了柔性襯底ITO薄膜的制備工藝條件。制得樣品的最佳可見光平均透過率為85．6％，方塊電阻為6Ω／口。

Abstract:采用水溶液恒電流電化學(xué)聚合法在純鈦表面制備了PPy涂層（Ti／PPy）。利用傅里葉紅外光譜、X射線光電子能譜測(cè)定表面化學(xué)成分。用掃描電子顯微鏡觀察涂層微觀形貌，接觸角測(cè)量?jī)x檢測(cè)接觸角并計(jì)算表面能。搭接剪切法測(cè)定涂層與基底間的結(jié)合強(qiáng)度。通過對(duì)成骨細(xì)胞在Ti／PPy表面附著、鋪展以及增殖能力的檢測(cè)，評(píng)價(jià)Ti／PPy對(duì)成骨細(xì)胞生長(zhǎng)的影響。結(jié)果表明，Ti／PPy的表面能（59．5mJ／m^2）高于純鈦（47．0mJ／m^2），并且具有良好的結(jié)合強(qiáng)度（9．16±1．62）MPa。Ti／PPy與Ti一樣具有良好的生物相容性，成骨細(xì)胞能夠在Ti／PPy涂層表面完成附著、鋪展以及增殖的生物功能。

Abstract:采用熔鹽電解法，將摻雜CaCO3的TiO2燒結(jié)體（作為陰極），在900℃熔鹽CaCl2中還原成金屬鈦。借助SEM，EDS及XRD分析了燒結(jié)后的陰極形貌、成分及相組成，考察CaCO3對(duì)電解提取鈦反應(yīng)的影響。結(jié)果表明：在TiO2陰極中摻雜CaCO3可以增加燒結(jié)后的陰極片孔隙度，并影響TiO2顆粒尺寸的大小，有利于加快陰極電解反應(yīng)的速度，提高電解效率。

Abstract:High pure tungsten (W, 99.99%) were prepared by chemical vapor deposition (CVD), then high pure tungsten and polycrystalline tungsten prepared by powder metallurgy (PM) process were impacted using Split Hopkinson Bar (SHB) over a narrow range of strain rates, 1000 s-1~2000 s-1. The deformation mechanisms were analyzed by optical microscope (OM). The results show that the main deformation mechanisms of the polycrystalline tungsten prepared by Powder Metallurgy Process are slip and grain-boundary slide, while those of high pure tungsten are slip, twinning deformation and grain-boundary slide. The interaction between the neighbouring twinnings may induce two kinds of intergranular cracks, which is the key reason of the high pure tungsten em-brittleness. The adiabatic shear band (ASB) is not found for the high pure tungsten under the strain rate in this paper e.g. lower than 103 s-1, so the plastic deformation ability of the high pure tungsten can not be improved as that of tungsten heavy alloy (WHA).

Abstract:將Zr-Sn-Nb新鋯合金樣品分別進(jìn)行多種變形熱處理，用透射電子顯微鏡研究它們的顯微組織和第二相粒子。然后把它們放入高壓釜中，在350℃，16．8MPa，0．01mol／LLiOH水溶液中腐蝕。結(jié)果表明：580℃-3h／冷軋／500℃-30h處理的樣品具有最好的耐腐蝕性能，這是因?yàn)樵摌悠分衂r-Fe-Nb第二相粒子呈均勻細(xì)小分布，且體積分?jǐn)?shù)在幾種樣品中最高，導(dǎo)致基體中的Nb元素同溶含量最低。

Abstract:La-Mg-Ni system (PuNi3-type) La0.7Mg0.3Ni2.55-xCo0.45Cux (x=0, 0.2, 0.4) hydrogen storage electrode alloys were prepared by casting and melt spinning process. The microstructure and electrochemical performances of the as-cast and melten spun alloys were analyzed and measured. The effects of substituting Ni with Cu and melt spinning on microstructures and electrochemical performances of the as-cast and melten spun alloys were investigated in detail. The obtained results show that the as-cast and melten spun alloys are composed of the (La, Mg)Ni3 phase and the LaNi5 phase as well as the LaNi2 phase. The melt spinning have an inappreciable influence on the phase compositions of the alloys, but leads to the homogeneity of the diffraction peaks of the alloys. The results obtained by the electrochemical measurement indicate that the substitution decreased the discharge capacities of the as-cast and melt spun alloys, whereas improved the cycle stability and discharge voltage characteristic of the as-cast and melten spun alloys. The melt spinning significantly improved the cycle stability of the alloys, but it notably decreased the discharge capacity of the alloys.

Abstract:Different-rate rapid quenching was used in the preparation of low-Co AB5 hydrogen storage alloys in order to improve its electrochemical properties. The results show that proper quenching not only increased discharge capacity greatly but also can improved cycle stability and discharge voltage property. Adopting 18 m/s rapid quenching, the alloy can get better electrochemical properties. Mierostructure and phase structure of as-cast and quenched alloys were observed by XRD and SEM. The rapid quenching effects on the electrochemical properties of low-Co hydrogen storage alloy are discussed.

Abstract:以NH4VO3，LiCl2和NiCl2等為原料，以氨水為pH調(diào)節(jié)劑，采用超聲凝膠方法制備了LiNiVO4納米晶。并采用XRD，TEM，IR，DTA和TG等分析手段對(duì)產(chǎn)物進(jìn)行了表征，通過差熱分析對(duì)其合成活化能進(jìn)行了研究。發(fā)現(xiàn)在超聲功率為300W時(shí)，于500℃下保溫1h，可以合成10nm左右的LiNiV04微晶顆粒，其合成活化能為47．7kJ／mol。電化學(xué)性能測(cè)試結(jié)果表明，在0．2mA／cm。充放電流密度和3．0V～4.8V電壓范圍內(nèi)，首次充電容量為103mAh／g，放電容量為75mAh／g，循環(huán)次數(shù)達(dá)4次后，放電容量還有62mAh／g，明顯優(yōu)于目前所報(bào)道的同類材料。

Abstract:Based on thermodynamics and kinetics theory, a theoretical model to illuminate the process for preparing metal nanopowders by anodic arc discharging plasma method was set up, and the origin of plasma, metallic evaporation, the mechanism of particle nucleation and growth were investigated. The influences of various technology parameters on the properties of nanopowders by Anodic Arc Plasma were also discussed. In addition, the samples prepared by this method were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and the corresponding electron diffraction (ED) to determine the crystal structure, morphology, particle size and particle size distribution. The experimental results show that the crystal structure of the nanopowder sample is the same as the bulk material, being fcc structure, with an average size about 16 nm, distribution ranging from 10 nm to 40 nm. The technology parameters (such as the power supply, the pressure of gas, the arc current intensity, water-cooling condition, etc.) have great effect on the particle nucleation and growth, the particle size can be effectively controlled by varying the technological parameters.

Abstract:在孔深60gm，直徑200nm的通孔氧化鋁模板中，用60mmol·dm^-3。Pd（NH3）4Cl2＋40mmol·dm^-3NiSO4·6H2O＋0．2mol·dm^-3NH4Cl，pH8．5和70mmol·dm^-3。Pd（NH3）4Cl2＋30mmol-dm^-3NiSO4·6H2O＋0．2mol·dm^-3NH4Cl，pH8.5的2種電解液，采用直流電沉積的方法制備鈀鎳合金納米線陣列。借助掃描電子顯微鏡（SEM）和X-射線能譜儀（EDX）表征納米線的形貌和成分。結(jié)果表明，用-0．6V～-0．8V（vsSCE）的直流電沉積，在氧化鋁（AAO）模板中可以成功地制備出鎳含量在8％～15％（質(zhì)量分?jǐn)?shù)，下同）之間的Pd-Ni合金納米線有序陣列，其直徑和模板的孔徑是一致的。沉積電勢(shì)負(fù)移將使得電流密度增加，有利于合金中電勢(shì)較負(fù)金屬鎳含量的增大。

Abstract:Nanocrystalline nickel and micro-grained nickel was prepared by pulse electrodeposition, and the corrosion behavior of electrolytic nickel, coarsed-grained nickel and nanocrystalline nickel in 3.5%NaCl solution and 10%HCl solution was studied by soak method and electrochemical polarization method, respectively. Three nickel samples all exhibited well corrosion resistance in 3.5%NaCl solution, however, nanocrystalline nickel was easier to be corroded due to the increase of fraction of interface volum. In 10%HCl solution they also showed good corrosion resistance, the nanocrystalline Ni presented the weakest corrosion resistance among the three nickel samples.

Abstract:采用醇還原的方法合成了聚陽(yáng)離子（聚二烯丙基二甲基氯化銨，PDDA），顆粒的zeta電位為＋32mV，粒徑約4nm。在靜電引力作用下將聚陽(yáng)離子修飾的金顆粒組裝到Nafion^TM212膜表面制成抗甲醇滲透質(zhì)子交換膜。在60℃，2mol／L的甲醇溶液中，甲醇滲透電流由168mA／cm^2下降到18mA／cm^2，其組裝的單電池具有更好的開路電壓和輸出性能。

Abstract:The Mg-Ni alloy was prepared by mechanical alloying. XRD and TEM analysis were used to indentify the microstructure and the phase of the Mg-Ni composite during the milling process, the thermodynamic properties of nanocrystalline Mg-Ni alloy were measured The results show that the alloy powder can be prepared by mechanical alloying on the condition that the milling technological parameters were strictly controled, The particle sizes of the powder were between 10 nm and 20 nm. At P-C isotherms there existed good plateau curves with long-width plateau.The nanocrystalline Mg-Ni alloy had a hystersis effect during hydrogen absorption/desorption and the effect decreased with the increase of temperature. The nanocrystalline Mg-Ni alloy has satisfied properties of hydrogen storage and a promising value of engineering application.

Abstract:采用粉體化學(xué)鍍技術(shù)，以AgNO3取代常見的貴金屬鹽PdCl2作為活化劑、H2PO2取代Sn^2＋作為還原劑，經(jīng)一步前處理過程，在空心微珠表面沉積NiCoP臺(tái)金。利用掃描電鏡、能譜分析儀以及X射線衍射分別討論了沉積層的形貌、成分和相結(jié)構(gòu)。結(jié)果表明：NiCoP合金均勻沉積在空心微珠表面；結(jié)合X射線光電子能譜儀觀察到的銀元素化學(xué)態(tài)的變化過程，提出了這種改進(jìn)工藝的一種可能機(jī)理。

Abstract:GdPO4:Eu3+ nanoparticles were prepared by precipitation method under different conditions with different pH, EDTA-2 Na and different annealing temperatures. The structure, morphology and luminescence characterization of GdPO4:Eu3+ nanoparticles were studied by XRD,SEM and luminescence spectrum. The results of XRD and SEM indicated that all of samples consisted of pure phase GdPO4:Eu3+, the size, and growth of crystal interface were related to synthesis conditions. The results of emission spectra and excitation spectra showed that the relative intensities of emission peaks increased with increasing of pH and annealing temperature, and the emission and excitation intensities of sample prepared with EDTA was lowered due to residual organic groups on the surface. The doping concentration of nanoparticles is about 8x%.

Abstract:采用水熱法在160℃下合成了單相橄欖石結(jié)構(gòu)的LiFePO4和LiFe0.95Ni0.05PO4。經(jīng)550℃聚丙稀裂解碳包覆后得到LiFePO4／C的顆粒尺寸在200nm左右，碳包覆鎳摻雜LiFe0.95Ni0.05PO4/C的顆粒尺寸在100nm以下。電化學(xué)測(cè)試結(jié)果表明：LiFePO4/C和LiFe0.95PO4／C的0．1C首次充放電可逆容量分別達(dá)到154mAh·g^-1和149mAh·g^-1，但摻鎳的LiFe0.95Ni0．05PO4／C具有更優(yōu)異的大電流充放電循環(huán)特性，0．5C和1C充放電100次后的放電容量分別達(dá)到147mAb·g^-1和134mAh·g^-1。

Abstract:Using self-made semi-solid mechanical stirring process system, the solidification behavior of Pb-15wt% Sn alloy semi-solid slurry with solid fraction beyond 0.6 was investigated under stirring condition. A detailed microstructural analysis of the solid phase was carried out. The results show that the solid-liquid separation is obvious in the samples with the solid fraction beyond 0.6 and the solid phase is dispersed quasi-globular particles. Based on these results, a kind of single-crystal powders coated with Pb-Sn eutectic was made by continuous stirring and cooling under the semi-solid state and a new method for preparing metal powder is developed. The analysis and discussion indicate that this approach can reduce the content of oxide and impurity in the powder.

Abstract:The influence of sintering process on the density of nano-AgSnO2 composite was investigated using AgSnO2 powder prepared by electroless plating, adopting air sintering, hot pressing and vacuum sintering. The results show that density changed with compacting pressure, sintering temperature and sintering time when sintered in air, while the final density was close after repressing and resintering. For hot pressing, a density with higher than 96% could be achieved in a short time, but serious expansion and blistering ocurred. Vacuum sintering could help to wipe off adsorbates, but some residual still remained in the compact, and the expansion occurred during resintering. Low pressure compaction and step isothermal sintering could remove most of the adsorbates, and a high density of 94% was obtained after resintering. The large amount of absorbates on nano-AgSnO2 powder surface which led gases closed in the compact during sintering were found to be the main causes that affected densification process .

Abstract:Sm-Co基整體輻向永磁環(huán)由于成型困難及燒結(jié)時(shí)易于變形和開裂等原因，限制了其應(yīng)用和發(fā)展。為此，本文對(duì)Sm（Co，F(xiàn)e，Cu，Zr）：整體輻向永磁環(huán)的燒結(jié)制備工藝，以及燒結(jié)和時(shí)效處理對(duì)磁體性能、組織結(jié)構(gòu)的影響進(jìn)行了研究。結(jié)果表明：調(diào)整合適的燒結(jié)工藝，能有效地抑制永磁環(huán)缺陷的產(chǎn)生，改善磁體的性能：在1220℃下燒結(jié)70min時(shí)磁體的性能較好，Br≥1．08T，Hcj≥2200kA／m，（BH）max≥214kJ／m^3；燒結(jié)磁體的矯頑力主要與時(shí)效工藝有關(guān)，時(shí)效前磁體主要是2：17型相的過飽和固溶體，在時(shí)效過程中析出1：5型相，并逐步形成胞狀的顯微組織結(jié)構(gòu)，磁體的內(nèi)稟矯頑力Hcj明顯增加，在850℃時(shí)效8h，磁體的Hcj可達(dá)到2200kA／m以上。如果在850℃時(shí)效時(shí)間過長(zhǎng)，胞狀組織會(huì)被破壞，磁性能開始惡化。

Abstract:An YBCO sample with high critical current density or single crystal stracture, can be obtained by the directional solidification method. In the present paper the morphology and chemical composition at the growth front of YB CO crystal have been investigate in order to it make clear the stopped growth mechanism of YBCO crystal growth during melt growth moment of the directional solidification. It is found that YBCO crystal will cease growing when yttrium and barium are depleted and copper becomes rich element in the liquid phase at the YBCO crystal growth front. For maintaining the continuous growth of YBCO, the composition of Y, Ba and Cu in raw sample has to be adjusted so as to make yttrium and barium enrichments in the liquid phase at the YBCO crystal growth front during the melt growth process.

Abstract:The microstructure and the corrosion property of AZ61 magnesium alloy stirred by permanent magnet (PM) were investigated. Based on the principle of electromagnetic field and magnetohydrodynamics, the force field of liquid metal in a PM field was analyzed. As a result, liquid metal in a PM experiences radial and tangential forces that are cyclically variational both in direction and magnitude. This phenomenon, namely electromagnetic vibration, influences matrix microstructure, subsequently affects corrosion property of the matrix.

Abstract:采用原位合成技術(shù)成功制備了Ag／Y2O3和Ag／CeO2電接觸材料。X射線衍射分析表明反應(yīng)合成材料中的相是Ag和Y2O3，C2O2：BSE圖像顯示：稀土氧化物在基體中呈球狀彌散分布，粒徑約為0．1μm～0．4μm，界面清潔，內(nèi)氧化層與基體結(jié)合良好，改善了增強(qiáng)相與基體浸潤(rùn)不良的問題，并使材料致密度得到提高。測(cè)量材料的物理性能和力學(xué)性能，發(fā)現(xiàn)2種氧化物對(duì)基體的影響基本趨于一致。分析氧化物的原位形核機(jī)制，認(rèn)為是氧在基體金屬中通過克服原子間勢(shì)壘擴(kuò)散進(jìn)入合金內(nèi)部，發(fā)生擇優(yōu)氧化。擴(kuò)散的主要方式是體擴(kuò)散，生成的增強(qiáng)相牢固地嵌入基體，使得該復(fù)合材料的界面結(jié)合緊，綜合性能優(yōu)良。

Abstract:The research progress on the brittleness of the Laves NbCr2 compounds at ambient temperature is sumarrized. The embrittlement mechanism and several methods of improving toughness of NbCr2 are mainly introduced, such as grain refinement, alloying and soft phase toughening. Finally, the existing problems in these researches are put forward and the future research fields are suggested.

Abstract:The latest research status with respect to microstructures, properties and interface behavior of different particulate reinforced magnesium (PRM) matrix composites was reviewed. Based on the problems included in the study of PRM matrix composites, four research orientations in the future are suggested in the present paper, including the development of effective methods to control the interface behavior between reinforced particulates and matrices, the preparation methods of low cost to in-situ fabricate PRM matrix composites, the combination of different processing technologies, and the study of computer simulation technologies for strengthening and failure mechanisms of PRM.