Reconstruction of Mandibular Defect with Porous β-TCP/BMG Artificial Bone

1Introduction Reconstructivesurgeryisoneofthehottestre searchedsubjectsthatdealingwithbonedefects.Thetra ditionalmethodisimplantationoffreshautograftbonebe causeofitsnon immunoreactiveproperty.Butautologousbonewasnotabundantinsomecases.Sowefoundbeta trica…     

氧化锌对高胶凝性水泥熟料矿物形成及强度的影响

采用工业原料配料，对以硅酸三钙（C3S，C=CaO，S=SiO2）、硫铝酸钙（C4A3 S^-，C=CaO，A=Al2O3，S^-=SO4^2-）为主导矿物的含C4A3 S^-矿物硅酸盐水泥熟料的矿物形成及其强度进行了研究。借助X射线衍射和热重一差热分析研究了矿物形成过程；探讨了微量元素ZnO对熟料性能的影响及在熟料体系中的固溶情况。研究结果表明：生料中掺入ZnO可使C4A3 S^-和CaS等矿物通过低温反应形成，共存于同一熟料体系中，并可提高熟料的强度；过高的ZnO含量亦会降低C4A3 S^-矿物的分解温度。     

一种具有发展前景的饲料磷酸盐——脱氟磷酸三钙

脱氟磷酸三钙由于含钙量高、钙磷比适合于喂养家禽，是良好的饲料磷酸盐。它是由磷矿和其它添加物团粒，经高温焙烧后制成。具有工艺流程简单、生产成本低等优点。可结合本地情况，发展生产。     

C3S在NaOH和水中早期水化的ESCA研究

用ＥＳＣＡ研究了Ｃ３Ｓ在水中和ＮａＯＨ溶液中水化１－１０ｍｉｎ试样的表面组成;用等离子发射光谱仪测定了Ｃ３Ｓ早期水化液相中的组成,结果表明：Ｃ３Ｓ早期水化表面组成ｎ（Ｃａ）／ｎ（Ｓｉ）〉３,或ｎ（Ｃａ＋Ｎａ）／ｎ（Ｓｉ）〉３,形成一富Ｃａ层,初步认为Ｃ３Ｓ在ＮａＯＨ溶液中水化,Ｃａ＾３＋溶出受阻而Ｓｉ＾４＋溶出加快：Ｎａ在水化早期进入双电层和表面组成中,实验表明,欲采用ＥＳＣＡ技术测定Ｃ３Ｓ早期水     

食品级、医药级磷酸三钙生产工艺

采用改进的固相反应法，以碳酸钙和工业磷酸为原料，制备食品级、医药级磷酸三钙(TCP)产品，研究了CaO与P2O5物质量的比、助剂加入量、反应温度对产物化学组成结构的影响；用X射线衍射(XRD)研究了产品的物相结构。提出了该工艺的反应机理，并确定了在技术上、经济上可行的工艺路线。分析结果表明，可以得到高品质磷酸三钙，产品质量指标符合FCC、USP和EP标准。     

Effect of barium oxide on the formation and coexistence of tricalcium silicate and calcium sulphoaluminate

Formation and coexistence of tricalcium silicate (C₃S) and calcium sulphoaluminate (C₄A₃ ) minerals in Portland cement clinker containing calcium sulphoaluminate were investigated. The f-CaO content, mineral composite and formation of mineral in the clinker were analyzed respectively by chemical analysis, differential scanning calorimetry(DSC) and X-ray diffraction. The results show that, adding a suitable amount of BaO can improve the burnability of raw meal and promote the f-CaO absorption. Tricalcium silicate and calcium sulphoaluminate minerals can form and coexist in clinkers at 1 234–1 317 °C by the addition of BaO to the raw meal. A suitable amount of BaO expanded the coexistence temperature of two minerals by 58 °. Funded by the National Basic Research Program of China (No. 2009CB623100), National Eleven Five-Year Scientific and Technical Support Plans (No. 2006BAF02A24), the Natural Science Fund for Colleges and Universities in Jiangsu Province(No. 08KJB430006), the Open Fund for the Key Laboratory of Inorganical and Composite Materials in Jiangsu Province(No. wjjqfhxc1200801) and the Innovation Fund of Doctoral Dissertation of Nanjing University of Technology (No. BSCX200705)     

拜耳法助滤剂研制

拜耳法氧化铝生产中。溶出矿浆经重力分离沉降槽液固分离后。溢流溶液中仍然合有一定的浮游物杂质．在分解之前。需要对溢流进行二次净化，以脱除其中的浮游物。国内拜耳法氧化铝厂目前采用的二次净化方法一般是用凯利叶滤机过滤。受溢流溶液的物理化学性质的影响，叶滤机产能常常会受到溢流溶液过滤速率的限制。铝酸三钙既能加快拜耳法溶液的过滤速率，又能降低滤液的浮游物含量。本文论述了合成铝酸三钙的技术条件对其助滤性能的影响。研究表明，合成温度、钙铝摩尔比、碱浓度会影响助滤剂铝酸三钙的粒度分布、晶体结构及组成，继而影响其助滤性能。控制适宜的合成条件。可以制备出助滤性能优良的铝酸三钙。     

Effects of molecular structure of polycarboxylate-type superplasticizer on the hydration properties of C3S

Effects of polycarboxylate-type superplasticizer(PC) molecular structure on the hydration heat of tricalcium silicate(C3S) paste and polymerization degree of hydration products(C-S-H gel) were researched by using TAM AIR isothermal microcalorimetry(TA) and 29Si nuclear magnetic resonance(NMR).Methoxy polyethylene glycol-methacrylates-based polycarboxylate superplasticizers with different side chain lengths and main chain lengths were employed.PC molecules with shorter main chain or longer side chains caused stronger retardation of C3S early hydration and lesser increase of C3S 3 d hydration degree.NMR measurement indicated that the incorporation of PC increased the hydration degree of C3S paste and the polymerization degree of silicon-oxygen tetrahedron of C-S-H gel.The tendency for C3S 7 d hydration degree to improve was more pronounced while PC molecules with longer main chain or shorter side chain were added.Whereas,PC molecules with longer main chains or longer side chains increased the 7 d polymerization degree of C-S-H gel.     

聚羧酸减水剂对不同晶型C3S早期水化放热的影响

采用水化微量热仪研究了不同类型聚羧酸减水剂对不同晶型C3S水化放热特性的影响。结果表明:单斜晶系(M)C3S、三方晶系(R)C3S的水化放热速率峰值相比三斜晶系(T)C3S显著降低,且水化放热峰出现延迟,MC3S的水化放热峰延迟最明显。三种晶型C3S的3d水化放热总量由大到小为:TC3S、MC3S、RC3S。不同分子结构的甲氧基聚乙二醇甲基丙烯酸酯系聚羧酸减水剂,主链越短,支链越长,对TC3S的水化延迟作用越大。乙烯基聚乙二醇醚系聚羧酸减水剂对三种晶型C3S的水化放热过程延迟作用由大到小为:RC3S、MC3S、TC3S。对水化放热曲线进行的Krstulovic-Dabic模型研究表明,C3S的水化过程为NG-D类型水化历程。     

Effect of Minor Elements on Silicate Cement Clinker

The effect of rare-earth and HX addition agent on the burn-ability of silicate cement dinker was investigated by orthogonal experiment. The result shows, compared with blank sample, f CaO of the .samples added with rare-earth and HX agent drops by 84.95% , its 3 d and 28d compressive strength enhances by 24.40% and 16.90% , respectively. It was discovered by means of X-ray diffrnction and high temperature microscope analysis that sintering temperature of the sample added with rare-earth and HX addition agent is about 1320℃. At the same time, the tmrning temperature of triealeium silicate desends and its crystal growth forming- rate increases. Tricalcium silicate content in burning clinker is higher and its crystal is larger.