Influence of Mg2+ Contents on the Thixotropy of HTlc/MT Suspensions

In this article, we found that the variation of Mg²⁺ content in the Fe-Al-Mg hydrotalcite-like compounds (HTlc) and the change of R values (R_defined = W_HTlc /W_MT) will influence the thixotropic and viscoelastic properties of HTlc/sodium montmorillonite (MT) suspensions. With increasing the content of Mg²⁺ in the HTlc samples, the storage modulus (G′) and the loss modulus (G″) of the HTlc/MT suspensions will increase gradually, which means the structure strength of the HTlc/MT suspension increases with increasing of Mg²⁺ content in the HTlc samples. In addition, the structure strength of the suspensions will increase with increasing of R values. Special emphasis has been laid on the phenomenon of thixotropy. As the gradual increase of the structure strength in the HTlc/MT suspension, the thixotropic types will change accordingly. The mechanism has been discussed emphatically.     

可调有序介孔炭在有机和硫酸电解液中的电容性质

采用硬模板法, 掺杂硼酸制备了一系列有序介孔炭材料, 并研究了其在有机和硫酸电解液中的电容性质. 结构分析表明, 该类炭材料具有平行排列的有序介孔孔道, 随硼酸摩尔分数从0增大至50%, 炭材料孔径尺寸从3.3 nm增大至5.7 nm, 表面含氧量从2.0%增大至5.2%(摩尔分数). 电化学测试表明, 在有机电解液中, 炭材料的电容性能主要是双电层电容, 含氧官能团没有引入明显的赝电容. 在硫酸电解液中, 掺杂5%硼酸制备的有序介孔炭材料BOMC-5的质量比电容值最大, 为140.9 F·g^-1; 随含氧量增大, 炭材料单位面积比电容值增大, 掺杂50%硼酸制备的炭材料BOMC-50的单位面积比电容值达到0.17 F·m^-2, 说明含氧官能团在硫酸电解液中引入明显的赝电容. 炭材料的表面化学性质决定了材料表面与电解液的浸润性, 是影响炭材料比电容保持率的主要因素.     

一种六核笼状锂配合物的制备、结构及合成机理研究

由[PhN(SiMe₂(OMe))Li]₂与哌啶腈通过加成反应合成了1种新型六核笼状锂配合物3,该配合物晶体结构已经确定,并用¹H NMR和X-单晶衍射对配合物3进行结构表征,其晶体呈笼状结构且属于单斜晶系：P2₁/n,a=1.248 83(19) nm,b=1.402 7(2) nm,c=1.853 4(3) nm;β=95.894(2)°;V=3 229.5(8) nm³,Z=2,R₁=0.047 7,GOF=0.946。     

Preparation and study on performance of submicron nickel powder for multilayer chip positive temperature coefficient resistance

Base metal nickel is often used as the inner electrode in multilayer chip positive temperature coefficient resistance (PTCR).The fine grain of ceramic powders and base metal nickel are necessary.This paper uses reducing hydrazine to gain submicron nickel powder whose diameter was 200-300 nm through adjusting the consumption of nucleating agent PVP properly.The submicron nickel powder could disperse well and was fit for co-fired of multilayer chip PTCR.It analyes the submicron nickel powder through x-ray Diffraction (XRD) and calculates the diameter of nickel by PDF cards.Using XRD analyses it obtains several conclusions:If the molar ratio of hydrazine hydrate and nickel sulfate is kept to be a constant,when enlarging the molar ratio of NaOH/Ni 2+,the diameter of nickel powder would become smaller.When the temperature in the experiment raises to 70-80 C,nickel powder becomes smaller too.And if the molar ratio of NaOH/Ni 2+ is 4,when molar ratio of (C 2 H 5 O) 2 /Ni 2+ increases,the diameter of nickel would reduce.Results from viewing the powders by optical microscope should be the fact that the electrode made by submicron nickel powder has a better formation and compactness.Furthermore,the sheet resistance testing shows that the electrode made by submicron nickel is smaller than that made by micron nickel.     

聚天冬氨酸与木质素磺酸钠复配物对碳酸钙阻垢性能的研究

通过静态阻垢法研究了国产聚天冬氨酸(PASP)、木质素磺酸钠(SLS)添加量对碳酸钙的阻垢性能.结果表明:PASP在5.0mg/L时阻垢率接近100%,SLS达300mg/L以上时阻垢率趋于平缓,浓度为600mg/L时,其阻垢率仍不足70%.PASP与SLS复合配方及在不同影响因素条件下阻垢性能的研究表明:复合配方(PASP 2.0mg/L SLS 5.0mg/L)的阻垢率接近100%,且适用于高钙、高pH值、高温的水系统中,并可在水系统中长时间停留.