27Al MAS-NMR study of inorganic polymer formation at ambient temperature

Inorganic polymers are a novel class of materials formed by the polymerization of silicon, aluminium and oxygen species to form an amorphous three-dimensional framework structure. The basis of this process is the alkaline solutions to induce a certain amount of Si and Al atoms to dissolve from a feedstock such as aluminosilicate. A study of ²⁷Al MAS-NMR was carried out in an attempt to understand the reaction mechanism of the inorganic polymerization at ambient temperature. Scanning electron microscopy (SEM) and X-ray diffractometry (XRD) were also employed to establish the composition and microstructure of the inorganic polymerization. Specimens were prepared with different Al/Si mole ratios from the starting materials. The higher the Al content, the more sufficient the Al atoms that can combine with SiO₄, and the longer the reaction time, the more the bonded Si-O-Al-O polymer structure, and then the higher the Al content, the fewer the octahedral Al with a uniform Si-O-Al-O structure in four directions, because four Al atoms are combined with SiO₄, resulting in a uniform Si-O-Al-O structure in four directions. The results show that they have an amorphous microstructure.     

Electrical properties of Al/conducting polymer (P2ClAn)/p-Si/Al contacts

Al/P2ClAn/p-Si/Al structure was obtained by the evaporation of the polymer P2ClAn on the front surface of p-type silicon substrate. The P2ClAn emeraldine salt was chemically synthesized by using propionic (C₂H₅COOH) acid. The current–voltage (I–V) characteristic of the structure was measured at room temperature. The capacitance–voltage–frequency (C–V–f) in terms of interface states over the frequency range of 10 kHz to 3 MHz has been investigated. The capacitance has decreased with increasing frequency, due to the interface states distribution. From the forward bias I–V plot for the sample, the ideality factor (n) and zero-bias barrier height (Φ_bp,0) were obtained as 4.84 and 0.787 eV, respectively. Under forward bias, the high value of the ideality factor and the dispersion in capacitance could be due to the interface state distribution, the interfacial insulator layer, the conducting polymer on the interface and inhomogeneity of the barrier height. The energy distributions and the relaxation times of the interface states were determined in the energy range of (0.387 − E_v) to (0.787 − E_v) eV.     

无机填料对高分子固体电解质与金属铝键合性能的影响

阳极键合技术是一种在MEMS封装技术中常用的一种方法,目前仅可实现玻璃与金属、玻璃与半导体材料的键合;试验采用聚氧乙烯(PEO)为基质,复配少量纳米无机填料,制备出新型的固态复合聚合物电解质作为新的阳极键合材料,通过采用DSC和XRD等分析手段研究PEO与无机填料的相互作用及导电机制,进而探讨聚合物固体电解质作为新型的封装材料在阳极键合应用中的可行性. 结果表明,无机填料的加入有效的抑制了PEO 的结晶,使得键合界面过渡层明显,键合质量良好.     

Creep mechanism of Mg-Nd-Zn-Zr alloy at ambient temperature

Magnesium alloy＇s creep stress exponent and creep mechanism at the room temperature were analyzed by TEM. Relationship among strain, stress and creep time was studied. The creep rate of some mechanisms were calculated. The results show that the dislocation mechanism is possible. The deformation mechanism is dislocation slipping on basal plane, and twinning improves creep deformation.     

Al2O3P/ZA27复合材料的高温摩擦磨损特性

借助SRV高温摩擦磨损试验机、SEM及能谱分析仪研究了Al2 O3p/ZA2 7复合材料的高温摩擦磨损特性。结果表明 :在边界润滑条件下 ,Al2 O3p/ZA2 7复合材料的高温磨损质量损失较ZA2 7合金降低 0 .0 0 5 34g ;摩擦因数随着增强颗粒体积分数的增加而降低 ,当增强颗粒的体积分数由 10 %增加到 30 %时 ,Al2 O3p/ZA2 7复合材料的摩擦因数由 0 .142降低到 0 .132 ,但均高于ZA2 7合金。其高温失效形式为犁削和疲劳磨损。     

La62Al15.7(Cu,Ni)22.3块体非晶合金的晶化行为

利用等温和变温晶化退火的方法对铜模吸铸La62Al15.7(Cu,Ni)22.3块体非晶合金的晶化行为进行了研究.结果表明,La62Al15.7(Cu,Ni)22.3块体非晶合金晶化过程分为3级,不同阶段的晶化产物分别为 La、Al3La和富Cu、Ni的未知相;非晶合金的驰豫激活能和3级晶化激活能的关系为:Eg相似文献   

A study on commercial pure Al (1050) after cold rolling at room temperature with various deformations using positron annihilation

Positron annihilation lifetime (PAL), Doppler broadening (DB), and Vickers microhardness measurements (Hv) were performed to study the isochronal annealing of commercial pure Al (1050) in the temperature range from room temperature (RT) to 823 K after cold rolling at RT with various deformations of 16%, 37%, and 54%. PAL measurements show a decrease in the average lifetime of positron (τ _av) followed by saturation at 190 ps as a function of annealing temperature. The results of Doppler broadening of annihilation radiation (S and W parameters) are found to be consistent with PAL measurements. The correlation between the characteristics of positron annihilation and Hv shows three annealing stages of microstructure in commercial Al, which are attributed to recovery, partial recrystallization, and complete recrystallization.     

DIFFUSIVITY OF Al IN AMORPHOUS ALLOY Fe_(78)Si_9B_(13)

Ion beam sputtering profiling in combination with SIMS technique was employed toinvestigate the Al diffusion in Fe_(78)Si_0B_(13)amorphous alloy.Between 320 and 380℃,thediffusion coefficients vary from 2.43×10~(-22) to 2.01×10~(-21)m~2s~(-1),and an Arrheniusrelationship was established as:D_0=2.02×10~_(12)exp(-1.17/kT)     

(Cu50Zr42Al8)98(Cr2Ni)2块状非晶合金的摩擦磨损性能研究

利用铜模吸铸法制备了直径为3mmm（Cu50Zr4Al8）98（Cr2Ni）2块状非晶合金圆棒。在拴一盘磨擦试验机上对该非晶合金的磨擦磨损性能作了测试，得出，在滑动速度增大的过程中，其磨损机理由轻微摩损向严重磨损转变，在滑动速度低于1．0m／s下，该非晶合金表现出良好的耐磨性。     

Nd60Fe30M10（M=Al，Si，Ga）系非晶永磁的性能与组织结构

采用真空快淬设备以辊速5m／s、10m／s、15m／s、20m／s、30m／s制备了Nd60Fe30M10（M=Al,Si,Ga）系的“非晶带”,研究了制备速度对“非晶带”永磁性能和结构的影响。实验结果表明：Nd60Fe30Si10和Nd60Fe30Ga10同经典合金Nd40Fe30Al10一样,也显示出非晶永磁性能,并且比相同条件下制备的Nd60Fe30Al10“非晶带”的永磁性能更好;三种“非晶带”的矫顽力随辊速的降低而提高。对Nd60Fe30Al10“非晶带”的TEM分析表明,以30m／s辊速制备的“非晶带”,有2～5nm的析出物弥散分布在非晶基体上;而以5m／s辊速制备的“非晶带”,有10nm左右和150-200nm的析出物分布在非晶基体上。析出物的生成,促进了矫顽力的提高。     

Al对Fe-B-C-Si系合金的非晶形成能力和磁性能的影响

利用熔态旋淬法制备了系列铝含量的Fe-B-C-Si-Al系非晶合金薄带试样,采用X射线衍射仪(XRD)、差示扫描量热仪(DSC)和振动样品磁强计(VSM)研究了合金元素Al对Fe-B-C-Si系合金的非晶形成能力以及磁性能的影响。结果表明,Al元素明显提高Fe-B-C-Si合金的非晶形成能力,非晶合金薄带的临界厚度由无Al合金的小于35μm增加到含铝合金的70μm以上,并具有良好的塑性,可进行180o弯折而不断裂。饱和磁感应强度(Bs)也由无Al合金的1.52T增加到含铝合金的1.72T。     

Si—B（Al）-C—N系非晶和纳米陶瓷材料研究进展

Si-B（Al）-C-N系非晶和纳米陶瓷材料微观结构独特,高温性能优良,在高温结构材料与航天防热领域表现出诱人的虚用前景。从Si—B（Al）-C—N系陶瓷的主要制备方法与工艺特点,典型的组织特征和高温件能,以及Si-B（Al）-C-N基复合材料的性能特点等儿方面,综述了该系陶瓷材料的研究现状,展望了其发展趋势。     

Nd60-xPrxFe30Al10 (x=0, 9, 15)大块非晶合金的磁粘滞性研究

对Nd60-xPrxFe30Al10(x=0,9,15,at%)大块非晶合金的磁粘滞行为进行了研究,进而分析了该类合金的矫顽力产生机理。结果表明:Nd60-xPrxFe30Al10(x=0,9,15)合金在室温均表现为硬磁性,随着Pr元素含量的增加,合金的内禀矫顽力iHc逐渐减小。在合金的不可逆磁化率χirr随外磁场变化的曲线中,均在各自的内禀矫顽力附近出现了明显的峰。Pr元素部分替换Nd元素后,基本不影响合金的磁粘滞变化趋势。当Pr元素含量从0at%增加到15at%时,合金的热涨落场Hf略有减小,从11.1mT减小到9.9mT;激活体积Va由2.6×10-18cm3增加到2.9×10-18cm3;激活直径Da由17.1nm增加到17.7nm。激活直径Da的值与Nd基大块非晶里的纳米晶团簇(cluster)的尺寸相当,这可能是该类合金具有明显硬磁性的原因之一。     

Preparation and characterization of high salts polymer electrolyte based on poly（lithium acrylate）

1　INTRODUCTIONWorldwide research and efforts are currentlyunderway to fabricate all solid state, rechargeableLi and Li ion batteries utilizing Li+ conductivepolymer electrolytes[1]. Solid polymer electrolytespossesses many advantages including high ionicconductivity, high specific surface energy, solventfree, wide electrochemical stability windows, lightand easy processability[2]. Apart from polyethy lene oxide ( PEO )[3], poly ( vinyl alcohol )(PAV)[4], …     

(Fe1-xCox)84Zr3.5Nb3.5B8Cu1非晶合金的高温和低温磁性

用磁天平（MB）及提拉样品磁强计（ESM）研究了（Fe1-xCox）84Zr3.5Nb3.5B8Cu1（x＝0－0．8）非晶合金高温与低温磁性的变化，结果表明，该非晶态合金加热到800－900℃后，除x＝0．8的合金外，，合金的室温饱和磁化强度均比淬态有所提高；X射线衍射的结果表明，x＝0，0．2，0．4，0．6的合金中析出单一的a-Fe（Co）相，x＝0．8的合金中析出Co3B，FeB相，当x＝1．0时合金中析出单一的fccCo相。该非晶合金在1．5K时的饱和磁化强度σs随Co含量的增加先增大，当x＝0．2时达到最大值，然后随着x的增大，合金的σs逐渐下降。     

Correlations among factors of sulfide ores in oxidation process at ambient temperature

Spontaneous combustion is one of the serious problems in the mining of sulfide ore deposits. The relevant factors, e.g. oxygen absorption quantity, mass increase, contents of water soluble iron ions and sulfate ion of sulfide ore samples in the oxidation process were investigated both in theory and experiment. The results from the investigation show that there is no general interpretation relation among the oxygen absorption quantity, the contents of sulfate ion and water soluble iron ions during the oxidation process of sulfide ores at ambient temperature. However, there is a linear relationship between the mass increase of the sulfide ore samples in the oxidation process at ambient temperature and the quantity of oxygen absorption. Therefore, the simple and cheap mass scaling method is suitable for predicting the oxygen absorption performance of sulfide ores at ambient temperature in place of the expensive and complicated chemical method used hitherto. Furthermore, combined with other items of breeding-fire test, the mass increase potential can also be used to predict the spontaneous combustion tendency of sulfide ores.     

Ti53Cu27Ni12Hf3Al7Si3B1大块金属玻璃的制备及性能研究

用单辊甩带法和铜模铸造法制备了新型Ti基大块金属玻璃Ti53Cu27Ni12Hf3Al7Si3B1.DSC、DTA研究表明该合金具有较高的热力学稳定性,其第1晶化温度Tx1、玻璃转变温度Tg、过冷液相区间ΔTx以及约化转变温度Trg分别为705、750、45、0.63 K.压缩性能研究其压缩断裂强度、弹性模量和压缩塑性变形量分别为2 304 MPa、120 GPa和1.1%.研究发现,具有复杂拓扑结构的原子配比提高了Ti53Cu15Ni18.5Al7Hf3Si3B0.5大块金属玻璃的力学性能和热力学性能.