镍渣机械力化学效应及其对反应活性的影响

为提高镍渣的反应活性,根据机械力化学原理,采用高能球磨技术处理镍渣并采取蒸压工艺制备镍渣制品.通过粒径分析、X射线分析以及扫描电镜分析等手段研究不同高能球磨时间下镍渣的粒径、结构和形貌变化以及镍渣的反应活性变化.结果表明:高能球磨可以进一步细化镍渣,使大颗粒块状粉体破裂、表面粗糙化并提高镍渣的反应活性,长时间球磨可使水化样品诱导期和加速期两个阶段的水化放热量显著增大;高能球磨4 h时镍渣蒸压试块的强度最大,可达24.4 MPa,是未高能球磨时的4.5倍,球磨4 h后蒸压试块水化产物的X射线谱图中出现了硬硅钙石、托勃莫来石和镁水化物等衍射峰.     

S-HCPE力化学共聚物的合成

研究了苯乙烯(S)在高氯化聚乙烯(HCPE)上的力化学共聚反应.讨论了反应条件对力化学共聚反应及力化学共聚物结构的影响.通过红外光谱和核磁共振波谱对力化学共聚物的结构、组成进行了验证和表征.     

MECHANOCHEMICAL REACTION IN PROCESS OF GRINDING GOLD ORE

ＭＥＣＨＡＮＯＣＨＥＭＩＣＡＬＲＥＡＣＴＩＯＮＩＮＰＲＯＣＥＳＳＯＦＧＲＩＮＤＩＮＧＧＯＬＤＯＲＥＹｉＮａｎｇａｉ；ＸｕＸｉａｏｈｅ（ＤｅｐａｒｔｍｅｎｔｏｆＭｉｎｉｎｇＥｎｇｉｎｅｅｒｉｎｇ，ＮｏｒｔｈｅａｓｔｅｒｎＵｎｉｖｅｒｓｉｔｙ，Ｓｈｅｎｙ...     

Structure and electrochemical performance of spinel LiMn2O4 synthesized by mechanochemical process

1　INTRODUCTIONLithium ion battery was used in many areasbecause of its high voltage, high energy densityand long cycle life and so on. Spinel lithium man ganese oxide was one of the most promising mate rials in term of its environmental benign, low cost,easy preparation and temperature safety. Mainproblem is the poor cycle life. As we all know thatboth the structure and electrochemical performanceof material strongly depended on the preparingmethod and starting…     

Structural macrokinetics of synthesizing ZnFe2O4 by mechanical ball milling

Powder mixtures of Fe2O3 and ZnO were milled in a high-energy planetary ball mill to synthesize ZnFe2O4 and X-ray powder diffractometry was used to obtain the relative content of phases,crystallite size and microstrain of both Fe2O3 and ZnFe2O4. The lattice constants of Fe2O3 were obtained by cell refinement method.The macrokinetics and the structure evolution of matters were studied and the results show that the dynamics process of mechanochemical synthesis of ZnFe2O4 fits Avrami-Erofe’ev model and is controlled by a nucleation-growth mechanism,and the structural macrokinetics theory in combustion synthesis research area could be used to describe the kinetic process as well.     

木质纤维生物质物理化学作用过程的机械力化学

机械力化学是分子范围物质受机械力的作用而引起相关联的物理和化学变化现象的科学,它包括了物理张力下机械裂断和化学行为。作为一门学科最早兴起于粉体科学领域,逐渐拓展到其它学科。在木质纤维生物质研究利用过程中,从机械力化学作用原理,可以从不同的侧面理解木质素分离过程导致的木质素化学性质变化、机械浆返黄的原因以及磨浆对化学浆生物助漂规律等。在木质纤维生物炼制过程中,利用机械力化学有望实现一般物理、化学反应预处理难以实现的功能,达到改良生物炼制方法。     

Mechanochemical polymerization of styrene initiated by the grinding of quartz

The polymerization of styrene mechanochemically initiated by the wet grinding of quartz was attempted by using a vibrating ball mill with a laboratory scale. The effect of the grinding of quartz on the polymerization of the styrene was investigated by characterizing the polymer formed and the quartz ground. The results showed that styrene could also mechanochemically polymerize by the resulting active species of the grinding of quartz as well as methyl methacrylate. The polymerization was found closely related to the total surface area of the ground quartz. The molecular weight distributions of the polymer formed were not simply unimodal and remarkably broader than those of the methyl methacrylate. It was suggested that the polymerization of the styrene proceeded with a cationic active species from the experimental results and discussions. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2849–2855, 2001     

粉体机械力化学与淀粉微细化发展概况

综述了粉体机械力化学理论与各类淀粉破碎微细化的研究历史和发展状况,展望了未来的研究方向和应用前景。     

机械化学合成铁酸盐纳米晶的新进展

铁酸盐是一种重要的功能材料。本文介绍了纳米铁酸盐性质、应用及合成方法的特点。着重论述了机械化学法合成铁酸盐纳米晶的机制，并展望了该领域的发展趋势。