Ternary compounds and solid-state phase equilibria in Mg-rich side of Mg-Zn-Ca system at 300 ℃

The phase equilibria and compositions in Mg-rich side at 300 ℃ were investigated in Mg-Zn-Ca ternary system through the equilibrated alloy method by using scanning electron microscopy,electron probe microanalysis,X-ray diffraction and transmission electron microscopy.The results show that two ternary compounds T1 and T2 can be in equilibrium with the Mg-based solid solution in Mg-Zn-Ca system.T1 phase is a linear compound with the composition region（molar fraction） of 15% Ca,20.5%-48.9% Zn and balanced Mg at 300 ℃.Its hexagonal structure parameters decrease with increasing Zn content,i.e.a=0.992-0.945 nm,c=1.034-1.003 nm.T2 phase has hexagonal structure with the composition region of 26.4%-28.4% Mg,63.2%-65.5% Zn and 7.1%-8.4% Ca.At 300 ℃,the solubility of Zn in the Mg-based solid solution increases for the addition of Ca,the maximum solubility of Zn is 3.7%.Three-phase fields consisting of--Mg＋Mg2Ca＋T1,--Mg＋T1＋T2,--Mg＋T2＋MgZn and MgZn＋T2＋Mg2Zn3 exist in the Mg-Zn-Ca system at 300 ℃.

FORMABILITY AND CRYSTAL TYPES OF RARE EARTH-SILICON CONTAINING TERNARY COMPOUNDS

By pattern recognition chemical bond parameter method, the formability of NaZn13 type and BaCd11 type ternary compounds in RE-M Si （RE=La-Lu, M is any metallic element） systems has been investigated. And the existence of unknown ternary compounds is predicted by the pattern recognition method.

FORMABILITY OF TERNARY INTERMEDIATE COMPOUNDS IN SOME MOLTEN SALT PHASE DIAGRAMS

ＦＯＲＭＡＢＩＬＩＴＹＯＦＴＥＲＮＡＲＹＩＮＴＥＲＭＥＤＩＡＴＥＣＯＭＰＯＵＮＤＳＩＮＳＯＭＥＭＯＬＴＥＮＳＡＬＴＰＨＡＳＥＤＩＡＧＲＡＭＳ￥Ｋａｎｇ，Ｄｅｓｈａｎ；Ｗａｎｇ，Ｘｕｅｙｅ；Ｙａｏ，Ｓｈｕｗｅｎ；Ｃｈｅｎ，Ｎｉａｎｙｉ（Ｓｈａｎｇｈａｉ...

Topological Dirac surface states in ternary compounds GeBi_(2)Te_(4),SnBi_(2)Te_(4) and Sn_(0.571)Bi_(2.286)Se_(4)

Using high-resolution angle-resolved and time-resolved photoemission spectroscopy,we have studied the low-energy band structures in occupied and unoccupied states of three ternary compounds GeBi_(2)Te_(4),SnBi_(2)Te_(4) and Sn_(0.571)Bi_(2.286)Se_(4) near the Fermi level.In previously confirmed topological insulator GeBi_(2)Te_(4) compounds,we confirmed the existence of the Dirac surface state and found that the bulk energy gap is much larger than that in the first-principles calculations.In SnBi_(2)Te_(4) compounds,the Dirac surface state was observed,consistent with the first-principles calculations,indicating that it is a topological insulator.The experimental detected bulk gap is a little bit larger than that in calculations.In Sn_(0.571)Bi_(2.286)Se_(4) compounds,our measurements suggest that this nonstoichiometric compound is a topological insulator although the stoichiometric SnBi_(2)Se_(4) compound was proposed to be topological trivial.

PtCoNi ternary intermetallic compounds anchored on Co,Ni and N co-doped mesoporous carbon:Synergetic effect between PtCoNi nanoparticles and doped mesoporous carbon promotes the catalytic activity

Highly active and robust electrocatalysts are desired for proton exchange membrane fuel cells.Pt-based intermetallic compounds(IMCs) have been recognized as one of the most promising low-platinum catalysts for fuel cells(FCs).Herein,we report a high-performance IMCs by anchoring ordered PtCoNi ternary nanoparticles on the N,Co and Ni co-doped dodecahedral mesoporous carbon(DMC).While the introduced Co and Ni participate in the formation of PtCoNi IMCs,some of them are doped in the mesoporous carbon and coordinated by N to form Co-N_(y)/Ni-N_(z)dual active centers,which further enhances the electrocatalytic activity towards oxygen reduction reaction.Moreover,the addition of Ni results in a negative shift of the d-band center of Pt as compared to the Pt/DMC and Pt_(3)Co/DMC,making it easier to adsorb oxygen on the surface.As expected,our optimal sample Pt_(3)Co_(0.7)Ni_(0.3)/DMC exhibits excellent performance with mass activity and specific activity of 1.32 A mgPt-1and 1.98 mA cm^(-2)at 0.9 V,which are 7.33and 6.19 times that of commercial Pt/C,respectively.The Pt_(3)Co_(0.7)Ni_(0.3)/DMC also reveals much better cathodic performance in an H2-air single fuel cell than commercial Pt/C catalyst with a power density of0.802 W cm^(-2).This work provides critical sights into constructing efficient catalysts by ternary intermetallic strategy and synergetic effect between active components and support.

Structures and Magnetic Properties of Europium-Transition Metal-Gallium Ternary Intermetallic Compounds with 1:3 Type

The crystal structures and magnetic properties of novel Eu TrGa3-r （T=Pd, It, Rh） in termetallic compounds are investigated by using powder x-ray diffraction and magnetic measurements. EuTrGa3-r crystallizes in orthorhombic structure with space group of Cmcm and Z = 4. There are four kinds of nonequivalent 4c crystal positions in EuTrGaa-r unit cell, which are occupied by 4Eu, 4GaⅠ, 4（GaⅡ, T） and 4GaⅢ, respectively. EuTrGa3-r ex- hibits the complex magnetic states in low-temperature regime, with the three-, two- and one-antiferromagnetic transitions occurring for T=Ir, T=Rh and T=Pd, respectively. It might be due to the Kondo effect： a localized antiferromagnetic interaction of the isolated impurity spins with the surrounding conduction electrons at low-temperature regime.

SYNTHESIS AND STRUCTURE OF SbNB_3(Se_2)_6, A NEW ONE-DIMENSIONAL TERNARY NIOBIUM SELLURIDE COMPOUND

SbNb_3(Se_2)_6, Mr=1347.99, tetragonal, P4/mnc,a=b=9.466(2),c=19.075(3) ,V=1709.0(4) ~3, z=4, Dm=5.2(2)g/cm^3, Dc=5.24g/c^3,λ(Moka)=0.71069 ,μ=287.39cm^(-1), F(000)=2328,T=276(1)k,R=5.9％,Rw=6.9％, for 479 unique observed reflections (1>3σ(1)).The structure is composed of [Nb3(Se2)s]∞ chains along the c axis with Sb atoms inserted between them.

Isothermal section of Mg-rich corner in Mg-Zn-Al ternary system at 335 °C

The phase equilibria and compositions at the Mg-rich corner of the Mg?Zn?Al ternary system at 335 °C were systemically investigated through the equilibrated alloy method by using X-ray diffraction (XRD) and scanning electron microscopy (SEM) assisted with energy dispersive spectroscopy of X-ray (EDS). It is experimentally testified that theα-Mg solid solution is not in equilibrium with the Mg32(Al, Zn)49 (τ) ternary intermetallic compound orq quasicrystalline phase, but only in equilibrium with one ternary intermetallic compound Al5Mg11Zn4 (φ). The whole composition range of theφ phase was also obtained at 335 °C, i.e., 52.5%?56.4% Mg, 13.6%?24.0% Al, 19.6%?33.9% Zn (mole fraction). The solubility of Al in the MgZn phase is remarkably more than that in the Mg7Zn3 phase, and the maximum is about 8.6% Al. Aluminum and zinc are simultaneously soluble in theα-Mg solid solution.

Phase equilibria of Zn-Al-Ti ternary system at 450 and 600℃

The phase relationships in the Zn-Al-Ti system at 450 and 600℃ were experimentally determined using equilibrated alloys method.The specimens were investigated by means of scanning electron microscopy coupled with energy dispersive spectroscopy and X-ray diffractometry.Eleven and eight three-phase regions are confirmed in the 450 and 600℃ isothermal sections,respectively.The Ti2Al5 which only exists at high temperature(990-1199.4℃)in Ti-Al binary system is confirmed in two isothermal sections due to the dissolution of zinc.The T phase is confirmed as a ternary compound rather than an extension phase of TiZn3 at 450℃.The T2 phase is a new ternary phase stable at 450 and 600℃ in Zn-Al-Ti ternary system.

Investigation of Performance and Combustion Characteristics of DI Diesel Engine Fuelled with Ternary Fuel Blend at Different Injection Pressure

The depletion of fossil diesel fuels, global warming concerns and strict limits on regulated pollutant emissions are encouraging the use of renewable fuels. Biodiesel is the most used renewable fuel in compression ignition (CI) engine. The majority of literature agrees that the particulate matter (PM), unburnt total hydrocarbons (THC) and carbon dioxide (CO) emission from biodiesel are lower than from conventional diesel fuel. One of the most important reasons for this is the oxygen content of the biodiesel. This induces a more complete and cleaner combustion process. In addition to this the absence of aromatic compounds in biodiesel leads to particulate matter reduction with respect to diesel fuel. The potential emission benefits induced by the presence of oxygen in fuel molecules has increased the interest in using the bio-alcohols fuel blends in CI engines such as ethanol. Although alcohols are more suitable for blending with diesel fuel, properties like lubricity, viscosity, stability, heating value and cetane number of diesel-alcohol (Diesohol) still require improvement. One of the techniques is addition of biodiesel which can improve all of these properties forming diesel-biodiesel-alcohol (ternary) blends. The blends of diesel-biodiesel-ethanol can be used in the existing CI engines without any major modifications and most significant result of using this blend is the lower emission with almost the same performance as of diesel fuel alone. The present study focused on investigation of performance and combustion characteristics of ternary fuel blend in DI diesel engine operating at different injection opening pressure (IOP). The different injection opening pressures are: 180 bar, 200 bar and 220 bar.

钢渣基三元混凝土的制备及性能研究

为了促进钢渣的资源化利用,解决钢渣因活性低而导致实际应用受阻的问题,本文以钢渣、偏高岭土和硅灰为掺合料,设计L_(9)(3^(3))正交表并制备胶砂试件,研究掺合料配比、总掺量和钢渣细度三个因素对胶砂试件力学性能的影响,筛选出最优的水平因素组合,并在此基础上制备钢渣基三元混凝土,对最优水平因素组合进行优化验证。结果表明:胶砂试件受掺合料总掺量的影响最大,最优水平因素组合为掺合料配合比1∶2∶2(硅灰∶钢渣∶偏高岭土),总掺量20%,钢渣细度D_(90)为147μm;同时,以最优水平因素组合设计的钢渣基三元混凝土,与钢渣单掺混凝土相比,3 d抗压强度提升了31.71%,7 d抗压强度提升了54.21%,28 d抗压强度提升了9.84%;与标准水泥混凝土相比,3 d抗压强度提升了4.68%,7 d抗压强度提升了15.88%,28 d抗压强度提升了5.71%,满足钢渣作为掺合料实际应用到混凝土中对强度的要求。

复方苍术挥发油微乳的制备工艺研究

目的:对复方苍术挥发油微乳的处方进行筛选,考察其制备工艺条件。方法:根据复方苍术挥发油与油相、乳化剂、助乳化剂的互溶现象进行初步筛选,然后通过绘制伪三元相图,综合考虑微乳区域面积、微乳的外观、稳定性,最终确定处方组成,并在此基础上进一步对微乳的制备温度、搅拌速度、搅拌时间进行比较研究,测定微乳粒径。结果:复方苍术挥发油微乳的制备工艺为:将EL-40与异丙醇按3∶1的质量比混合,制得混合乳化剂,再取等质量复方苍术挥发油与油酸乙酯混合为油相,将混合乳化剂与油相按8∶2的质量比混合,在300 r/min,30±5℃条件下,加入蒸馏水搅拌10~15 min至澄清透明的微乳形成。微乳平均粒径为20.71 nm,分散系数为0.019。结论:复方苍术挥发油微乳的制备工艺简单可行,微乳澄清透明,粒径小、分布均匀,稳定性良好。

三元正极材料的复合改性研究进展

富镍层状金属氧化物镍钴铝酸锂/镍钴锰酸锂(NCA/NCM)是一种很有前途的锂离子电池正极材料。循环过程中界面不稳定、体结构退化和电极/电解质界面的副反应导致的容量快速衰退阻碍了其更大规模的商业应用。通过掺杂可以抑制阳离子混排和结构畸变,表面包覆可以保护粒子表面,抑制副反应,联合改性策略可以增强材料整体结构的稳定性,使材料具有良好的循环性能。据此,综述了近年来对富镍三元层状金属氧化物正极材料的复合改性研究进展,并阐述了改性的部分机理,最后对富镍层状金属氧化物正极材料的发展前景做了展望。

三元水滑石类化合物的合成及应用进展

二维纳米材料具有高比表面积和特殊的层间空间,因此展现出独特的物理化学性质。三元水滑石类化合物是重要的层状化合物,其多种金属离子的复杂性使其具有可调节的粒径分布、层间结构、孔隙分布、酸碱性、离子交换性和热稳定性等。通过对三元水滑石类化合物制备方法 的研究和精细结构的设计,使其在电化学、催化、吸附、聚氯乙烯(PVC)热稳定和医药卫生等领域展现出独特的应用潜力:作为电极材料可应用于碱性电池、氧气析出反应(OER)、亚硝酸盐氧化等过程;通过调节三元水滑石类化合物的离子配比,结合离子改性、负载、焙烧等方法 可将其用于罗丹明B(RhB)、亚甲基蓝、甲基橙等物质的光催化降解;利用三元水滑石类化合物的层间空隙,可以通过静电吸附或化学吸附实现重金属阳离子、阴离子及有机污染物的脱除;利用其碱性可吸收PVC分解产生的HCl,提高PVC的热稳定性;将三元水滑石类化合物与具有抗菌、抗癌、消炎功能的活性物质复合,可用于生物医药材料合成。

注二氧化碳驱替稠油技术研究进展

稠油具有黏度大、流动性差等特点,导致开采难度增大、采收率降低等问题出现。目前,注二氧化碳驱替稠油技术已在各大油田得到广泛应用,取得了一定效果,但实际应用与未来发展也面临一定挑战。驱油机理方面,二氧化碳可用于稠油开采,主要通过降黏、溶解等作用增强稠油的流动性。驱替技术方面,二氧化碳驱替稠油开采技术按介质个数可以分为一元驱替、二元复合驱替、三元协同驱替。二氧化碳吞吐技术是驱替普通稠油的主要方式;非均质性较强的特稠油、超稠油,需加入蒸汽、化学试剂等物质综合作用;“CO_(2)+”多元介质复合驱替技术是未来的发展趋势。实践效果方面,二氧化碳辅助三元协同驱替稠油技术采收率最高。二氧化碳辅助驱替稠油技术主要应用于普通稠油油藏,未来应在深层超稠油开采的适应性、二氧化碳埋存等方面加强理论研究和先导试验。

铕(Ⅲ)—β—二酮—碱三元配合物的合成及其光谱研究

本文合成了铕(Ⅲ)与五种β-二酮(乙酰丙酮Acac、苯甲酰丙酮BA、二苯甲酰甲烷DBM、三氟乙酰丙酮TFA和噻吩甲烷三氟丙酮TTA)和碱(邻菲罗啉phen、哌啶pip、NaOH)的十三种固体三元配合物,其组成为Euβ_3·phen或C^+[Ruβ_4]^-,(C^+=Hpip^+或Na^+)测定了它们的红外、紫外和荧光光谱,观察到当第二配体相同时,随着β-二酮分子中的甲基被苯基、三氟甲基或噻吩基取代时,其配合物的相对荧光强度增大,第二配体的性质与影响配合物的相对荧光强度,表明分子中离域π键范围的大小和含该键平面的刚性是影响其荧光性质的重要因素。

水化硅酸钙的结构及其变化

基于水化硅酸钙应用范围的扩展和混凝土的发展趋势,阐述了水化硅酸钙结构及其变化的研究进展。详细分析了无机和有机组分等因素对水化硅酸钙存在状态的影响。分析了水化硅酸钙与无机或有机组分间的相互结合原理。同时指出有机组分对水化硅酸钙组成结构的影响,是需要进一步深入研究的课题。

两温区气相输运和机械振荡合成ZnGeP_2多晶材料

ZnGeP2多晶的合成是其单晶生长的前提和基础,多晶材料的质量是生长高质量单晶的关键。因此,要获得高质量的ZnGeP2单晶体,必须提供高质量的ZnGeP2多晶材料。对两温区气相输运机械振荡法合成ZnGeP2多晶材料的工艺进行了研究,利用高纯(6N)P、Ge、Zn单质为原料,采用两温区气相输运和机械振荡合成出了ZnGeP2多晶材料。合成出的多晶材料经比重测试和X射线粉末衍射测试证明与标准值一致。采用改进的布里奇曼法生长出外观完整、无裂纹的15mm×25mm单晶体,在2.5～10μm范围内红外透过率达50%以上。

三元缔合物溶剂浮选光度法测定痕量硼

基于苦杏仁酸与B（Ⅲ）可生成稳定配位化合物，该配位化合物可进一步和孔雀绿形成三元缔合物，该缔合物难溶于水且不稳定，但易溶于苯、甲苯、二甲苯等有机溶剂，据此建立了溶剂浮选光度法测定硼的新方法。该法灵敏度高，ε=2．7×10^5mol·L^-1·cm^-1，大多数共存离子不影响测定。测10μg硼10次，RSD=1．9％；检出限为0．56μg／mL。实测了钢样和人发中硼，相对标准偏差为1．2％～4．7％，回收率在95．2％～100．1％之间。