基于X射线衍射法研究改性脱硫灰基生态橡胶的制备过程及机理

脱硫灰作为半干法脱硫技术主要副产品,其利用难度大且成本高,导致大量脱硫灰以直接堆放和填埋的方式处理,不但造成环境污染,而且浪费潜在资源。橡胶作为广泛应用的聚合物材料,在橡胶制备加工过程中需大量使用填料改善其力学性能、加工性能和填充增容。炭黑与白炭黑作为常用的橡胶填料,其不仅生产工艺繁杂,而且对能源和资源消耗量大,导致成本较高。面对上述问题,如何利用脱硫灰开发一种价格低廉的无机橡胶填料,既是固体废弃物高附加值利用又是资源可持续发展的重要途径之一,也是橡胶企业大幅降低填料成本提高经济效益的重要途径之一。由于脱硫灰属于无机材料,橡胶属于有机材料,为了更好的降低脱硫灰界面与橡胶界面(无机界面/有机界面)的不相容性,需要对脱硫灰进行化学改性处理。以该课题组前期取得的研究成果为基础,创新性以改性脱硫灰取代部分炭黑制备改性脱硫灰基生态橡胶。利用XRD对改性脱硫灰基生态橡胶制备过程各阶段的生产物质进行测试,即丁苯橡胶密炼胶制备阶段、改性脱硫灰基生态橡胶密炼胶制备阶段和改性脱硫灰基生态橡胶制备阶段,从微观层面揭示丁苯橡胶密炼胶制备过程、改性脱硫灰基生态橡胶密炼胶制备过程和改性脱硫灰基生态橡胶制备过程,阐明硫化过程中丁苯橡胶密炼胶与改性脱硫灰的结合机理。同时采用SEM对丁苯橡胶密炼胶与改性脱硫灰基生态橡胶密炼胶的微观形貌进行测试,以进一步佐证所获得的相关机理。结果表明:改性脱硫灰加入丁苯橡胶密炼胶后,改性脱硫灰基生态橡胶密炼胶的最大转矩F max大幅下降、最小转矩F L保持稳定、ΔF=F max-F L显著下降,同时焦烧时间t 10与正硫化时间t 90均缩短。硫化诱导期为0~387 s、硫化反应期为387~1586 s和硫化平坦期为1586~1800 s。在硫化诱导期形成非交联网络结构、硫化反应期前期形成基本交联网络结构、硫化反应期后期完善交联网络结构和硫化平坦期保持交联网络结构。以期为高附加值的脱硫灰资源化利用提供一定理论依据和技术支持。     

基于FTIR与XRD的改性脱硫灰取代部分炭黑 制备复合橡胶的补强机理研究

脱硫灰是半干法脱硫的主要副产品,其利用难度大且成本高,导致大量脱硫灰以直接堆放和填埋的方式处理,不但造成环境污染,而且浪费潜在资源。炭黑(8 000 元·t-1)与白炭黑(6 000 元·t-1)是常用的橡胶补强填料,生产工艺繁杂,消耗大量能源和资源,导致成本较高。面对上述问题,如何利用脱硫灰开发一种价格低廉的无机橡胶补强填料,既是固体废弃物高附加值利用的重要途径之一,也是橡胶企业大幅降低填料成本提高经济效益的重要途径之一。由于脱硫灰属于无机材料,橡胶属于有机材料,为了更好的降低脱硫灰界面与橡胶界面(无机界面/有机界面)的不相容性,需要对脱硫灰进行化学改性处理,以提高脱硫灰代替部分炭黑制备橡胶的力学性能。该研究创新性以硅烷偶联剂Si69、硅烷偶联剂KH550与脱硫灰制备改性脱硫灰,然后以改性脱硫灰取代部分炭黑制备复合橡胶。根据国家与行业标准测试复合橡胶的力学性能,如拉伸强度、撕裂强度和硬度。利用扫描电子显微镜(SEM)对复合橡胶的微观形貌进行测试与分析,傅里叶变换红外光谱仪(FTIR)对改性脱硫灰的组成结构进行测试与分析,X射线衍射仪(XRD)对改性脱硫灰的矿物组成进行测试与分析,以揭示硅烷偶联剂Si69与硅烷偶联剂KH550协同对脱硫灰的改性机理,以及改性脱硫灰对复合橡胶的补强机理。结果表明：采用硅烷偶联剂KH550与硅烷偶联剂Si69协同改性脱硫灰,其取代炭黑的增强效果最佳,即复合橡胶的拉伸强度为20.36 MPa、撕裂强度为45.71 kN·m-1和邵尔A硬度为66;硅烷偶联剂KH550与硅烷偶联剂Si69协同改性脱硫灰,不仅保持脱硫灰依然良好的碱性,有利于对复合橡胶起到增强效果;而且可以改善脱硫灰的表面特性与结构,提高改性脱硫灰与丁苯橡胶的无机界面/有机界面相容性。     

基于XRD与SEM研究风淬渣微粉用于重金属污染土壤的修复机理

钢渣是冶金工业中产生的主要固体废弃物,其产量约为每年粗钢产量的15%~20%。由于技术的局限,导致我国钢渣利用率较低,仅为年钢渣产量的10%,同时加之管理制度的不健全,导致钢渣大量露天堆放,对土地资源、地下水源,以及空气质量形成严重影响。面对上述问题,利用钢渣开发一种价格低廉的固化药剂用于重金属污染土壤的修复,既是冶金固体废弃物可持续发展的重要途径之一,也是大幅降低重金属污染土壤修复成本的重要途径之一。该研究创新性是用风淬渣微粉作为固化药剂对含有Cd,Cu,Pb,Ni和Zn的重金属污染土壤进行修复。研究了风淬渣粉磨时间、风淬渣微粉掺量和养护时间对修复重金属污染土壤效果的影响。利用激光粒度分析仪测试风淬渣微粉的粒度分布、比表面积与孔隙度吸附仪测试风淬渣微粉的孔结构、扫描电子显微镜测试风淬渣微粉-重金属污染土壤混合物的微观形貌、X-射线衍射仪测试风淬渣微粉的矿物成分,分析风淬渣微粉修复重金属污染土壤的机理。结果表明,风淬渣的性质安全,对生态环境不存在污染,可以用于修复重金属污染土壤的固化技术。当风淬渣粉磨时间为100 min、风淬渣微粉掺量为20%、养护时间为14 d时,风淬渣微粉对重金属污染土壤中Cu,Cd,Ni,Zn和Pb的固化效果均达到91%以上。随着风淬渣粉磨时间的延长,风淬渣微粉的粒径尺寸减小、粒度分布趋向均匀。风淬渣的多孔结构破坏、比表面积提高,有利于提高风淬渣微粉对重金属污染土壤的修复效果。随着风淬渣微粉掺量的增加,风淬渣微粉形成的水化凝胶（C-S-H）数量增加,有利于提高风淬渣微粉包裹重金属污染土壤的效果,以达到固化重金属污染土壤中Cd,Cu,Pb,Ni和Zn的目的。风淬渣微粉对固化重金属污染土壤中Cu,Cd,Ni,Zn和Pb具有选择性,在不同养护时间下,重金属分别以Cd₂SiO₄,Cu(OH)₂·2H₂O,PbCO₃,3Ni(OH)₂·2H₂O,Ni₂SiO₄,Zn(OH)₂和Zn₂SiO₄形式存在。     

XRD与SEM的钢渣尾渣物理激发机理研究

钢渣是冶金工业中产生的主要固体废弃物,其产量约为每年粗钢产量的15%~20%。由于技术的局限,导致我国钢渣利用率较低,仅为年钢渣产量的10%;同时加之管理制度的不健全,导致钢渣大量露天堆放,对土地资源、地下水源,以及空气质量造成严重影响。固体废弃物再利用是资源可持续发展的重要途径之一,由于钢渣的主要化学成分(CaO,SiO₂,A1₂O₃,MgO,Fe₂O₃,MnO,f-CaO等)、主要矿物组成(硅酸三钙、硅酸二钙、钙镁橄榄石、钙镁蔷薇辉石、铁酸二钙等)与水泥熟料的主要化学成分、主要矿物组成极为相似,是一种具有潜在胶凝活性的胶凝材料。以钢渣尾渣作为研究对象,采用机械研磨的方式对钢渣尾渣处理,即物理激发,获得不同粒径钢渣尾渣微粉。依据《用于水泥和混凝土中的钢渣粉》(GB/T 20491-2006)与《水泥胶砂强度检验方法(ISO法)》(GB/T 17671-1999)制备一系列钢渣尾渣胶砂试块(分别标记为A₄₀,A₆₀,A₈₀,A₁₀₀和A₁₂₀)。研究对钢渣尾渣胶凝活性的影响,以及不同水化时间对钢渣尾渣胶凝活性的影响,即3 d钢渣尾渣胶砂强度、7 d钢渣尾渣胶砂强度与28 d钢渣尾渣胶砂强度。利用激光粒度分析仪(LPSA)对钢渣尾渣微粉的粒径分布进行测试与分析,X射线衍射仪(XRD)对钢渣尾渣微粉与钢渣尾渣胶砂的矿物组成进行测试与分析,扫描电子显微镜(SEM)进行微观形貌测试与分析,从而获得钢渣尾渣的物理激发机理。结果表明,随着钢渣尾渣微粉粒径的减小,其胶凝活性呈现先增加后降低的趋势,当研磨时间为80 min时,A₈₀钢渣尾渣微粉的胶凝活性最高,即3 d活性指数为67.55%、7 d活性指数为71.96%和28 d活性指数为73.61%。随着钢渣尾渣微粉粒径的减小,钢渣尾渣微粉中RO相的XRD特征峰强度稳定,Ca₂SiO₄与Ca₃SiO₅的XRD特征峰强度呈现先增加后降低的趋势,Ca₃SiO₅与Ca₂SiO₄参与水化反应,生成一定量的Ca(OH)₂与C-S-H凝胶,具有良好的胶凝活性。A₈₀钢渣尾渣微粉中Ca₂SiO₄含量较少,而Ca₃SiO₅含量较多,均可以生成一定量的Ca(OH)₂与C-S-H凝胶,小幅提高A₈₀钢渣尾渣胶砂的早期(3~7 d)力学性能,大幅提高A₈₀钢渣尾渣胶砂的中、后期(7 d~28 d)力学性能。当水化时间3 d时,A₈₀钢渣尾渣胶砂中存在少量水化产物且大量分散小颗粒;当水化时间7 d时,A₈₀钢渣尾渣胶砂中水化产物大幅增加且形成较大颗粒;当水化时间28 d时,A₈₀钢渣尾渣胶砂中形成大量水化产物且几乎不存在分散小颗粒。从而进一步实现固体废弃物的资源化再利用,达到钢铁企业增加效益,环境缓解压力的目的。     

O2/CO2气氛下循环流化床煤燃烧SO2排放

在热输入功率50 kW的循环流化床O₂/CO₂燃烧试验装置上研究燃煤SO₂排放特性及石灰石脱硫机理。结果发现,未添加石灰石时,O₂/CO₂气氛下SO₂排放量比相同O₂浓度的空气气氛下低;随着O₂浓度的升高,排放量升高。相同钙硫摩尔比下,O₂/CO₂气氛下石灰石的脱硫机理以直接脱硫为主,脱硫效率比空气气氛下高;随着O₂浓度的增加,石灰石脱硫效率提高。     

H2S硫化CuInSe2生成CuIn(SxSe1-x)2薄膜的XRD及Raman分析

将CuInSe₂薄膜在H₂S与Ar的混合气体中硫化是制备CuIn(S_xSe_1-x)₂薄膜的一种常用方法。硫化所用到的CuInSe₂薄膜是用溶剂热法生成的CuInSe₂纳米颗粒旋涂而成。不同于其他真空条件下制备CuInSe₂薄膜的方法.溶剂热法的优点是其相对简单的制备工艺和较低廉的成本。对硫化过程进行研究后发现,硫化温度和时间直接影响CuIn(S_xSe_1-x)₂薄膜的质量,诸如薄膜成分、结晶度、均匀性和带隙宽度都可以通过改变这些实验条件来进行控制。     

Zr60Al15Ni25大块非晶合金晶化动力学研究

通过等温示差扫描量热法研究了Zr₆₀Al₁₅Ni₂₅大块非 晶合金的晶化动力学.实验结果表明，晶化过程的孕育期很短，即使在743 K这样低的温度下也不过0.52 min，而放热峰宽（反应整个晶化过程进行的时间）却随退火温度的降低明显增大，这说明了结晶过程是一个晶核长大控制的过程.Avrami指数表明在不同的退火温度，该合金的晶化机制发生了变化.晶化机制的变化是由于合金原子在不同温度下的扩散能力相差很大所致. 关键词： 晶化动力学 60Al₁₅Ni₂₅大块非晶合金')" href="#">Zr₆₀Al₁₅Ni₂₅大块非晶合金 示差扫 描量热法（DSC）     

悬浮区域熔炼法制备LaB6单晶体与发射性能研究

采用区域熔炼法成功制备出了高质量,高纯度,大尺寸的LaB₆单晶体. 系统分析了制备过程中每个参数对LaB₆单晶生长的影响,确定了晶体生长最佳工艺为:样品转速为30 r/min,生长速度为8-10 mm/h. 分析了单晶LaB₆ (100) 晶面的热电子发射性能,结果表明,当阴极温度为1873 K时,最大热发射电流密度为44.36 A/cm²;利用 Richardson 直线法求出了绝对零度逸出功和有效逸出功分别为1.99和2.59 eV. 场发射测试结果表明,单晶LaB₆场发射单尖最大场发射电流密度达到4.9×10⁶ A/cm²,场发射因子为41500 cm^-1,表现出良好的场发射性能. 因此单晶LaB₆作为热阴极和冷阴极都具有很广阔的应用前景. 关键词： 区域熔炼法 6')" href="#">单晶LaB₆ 热发射性能 场发射性能     

上转换纳米粒子CaF2:Er3+,Yb3+的合成及其温敏特性

采用水热合成法制备了CaF₂：Yb³⁺,Er³⁺上转换纳米粒子。在980 nm激发下,研究了来源于Er³⁺的²H_11/2/⁴S_3/2→⁴I_15/2跃迁的绿光发射和来源于⁴F_9/2→⁴I_15/2跃迁的红光发射。由于Er³⁺具有一对热耦合能级（²H_11/2/⁴S_3/2）,所合成的样品在293~573 K温度范围内有良好的温敏特性。利用荧光强度比（FIR）技术,测得样品在483 K时具有最大灵敏度0.002 85 K^-1。     

二氧化硅对稀土掺杂二氧化钛薄膜形貌与发光性能的影响

为提高稀土掺杂TiO₂薄膜的上转换效率,采用溶胶-凝胶法和旋涂镀膜工艺制备了Yb³⁺-Er³⁺共掺杂SiO₂/TiO₂上转换光致发光薄膜,研究了SiO₂对TiO₂薄膜形貌以及发光性能的影响。利用FE-SEM观察了薄膜的表面形貌,利用分光光度计测试了薄膜在近红外光区域的透射率的变化,并用荧光光谱仪测试了薄膜的上转换发光光谱。结果表明：SiO₂的掺杂导致TiO₂颗粒尺寸显著减小,TiO₂薄膜在近红外的透射率也有所下降。在980 nm红外光激发下,SiO₂/TiO₂薄膜在630~670 nm处获得了明显的上转换红光发射,在516~537 nm和537~570 nm处获得了较弱的上转换绿光发射。由上转换发光强度与激光泵浦功率的关系推知,绿色和红色上转换发光均为双光子吸收发射过程。     

Effect of the Rubber Components on the Mechanical Properties and Braking Performance of Organic Friction Materials

Vegetable oil modified phenolic resin (PF) mixed with four kinds of rubber modifiers, i.e., styrene butadiene rubber, styrene butadiene 2-vinyl pyridine rubber, nitrile butadiene rubber, and carboxyl nitrile butadiene rubber (CNBR), were used as matrices for organic friction materials. The mechanical and thermal degradation properties of all of the blends were investigated. Friction and braking tests of the organic friction materials based on the different matrices and reinforced with hybrid fibers were carried out. The results showed that the resin was most compatible with CNBR; the CNBR/PF blend possessed much higher impact and toughness, and the friction material based on this blend as a matrix exhibited better friction and braking performance. It was concluded that CNBR, the rubber with the most reactive groups, resulted in better mechanical properties of the friction material, and hence optimized the friction, wear and braking performances.     

Carbon Black–Filled Styrene Butadiene Rubber Masterbatch Based on Simple Mixing of Latex and Carbon Black Suspension: Preparation and Mechanical Properties

An improved process was developed for the production of carbon black (CB)–filled styrene butadiene rubber masterbatch (SBR-CB-MB) using a simple latex/CB mixing technology; the improvement comprised processing the CB as an emulsifier-free aqueous suspension by high-rate shearing. Tensile and tear strength, dynamic compression behaviors, the Payne effect, equilibrium swelling and bound rubber of the SBR-CB-MB and dry mixing CB filled SBR (SBR-CB-DM), covering a wide range of CB loading (45–70 phr), were investigated and compared. It was found that the tensile and tear strength, heat buildup and compression set, abrasion volume loss, and the Payne effect of the SBR-CB-MB were lower than those of the SBR-CB-DM, while the bound rubber content were higher, indicating good CB/rubber interaction in the SBR-CB-MB. SEM analysis showed that no free CB could be found on the surface or inside of the granular SBR-CB-MB particles, indicating good CB dispersion in the rubber matrix.     

羧基丁苯胶乳中结合苯乙烯含量的红外光谱测定法

本文介绍了用红外光谱法测定羧基丁苯胶乳中结合苯乙烯含量的方法，通过该方法分别选择１４９５ｃｍ~（－１）作为苯乙烯的芳烃Ｃ＝Ｃ伸缩振动特征吸收带和９７０ｃｍ~（－１）作为丁二烯的反式Ｃ＝Ｃ非平面摇摆振动特征吸收带。结果求得直线回归方程，相关系数，相对标准偏差，精度范围等。本方法简单、快速、选择生强，已成功地应用于羧基丁苯胶乳中结合苯乙烯含量的测定。     

Combined measurement of X‐ray photon correlation spectroscopy and diffracted X‐ray tracking using pink beam X‐rays

Combined X‐ray photon correlation spectroscopy (XPCS) and diffracted X‐ray tracking (DXT) measurements of carbon‐black nanocrystals embedded in styrene–butadiene rubber were performed. From the intensity fluctuation of speckle patterns in a small‐angle scattering region (XPCS), dynamical information relating to the translational motion can be obtained, and the rotational motion is observed through the changes in the positions of DXT diffraction spots. Graphitized carbon‐black nanocrystals in unvulcanized styrene–butadiene rubber showed an apparent discrepancy between their translational and rotational motions; this result seems to support a stress‐relaxation model for the origin of super‐diffusive particle motion that is widely observed in nanocolloidal systems. Combined measurements using these two techniques will give new insights into nanoscopic dynamics, and will be useful as a microrheology technique.     

Rubber friction: Comparison of theory with experiment

We have measured the friction force acting on a rubber block slid on a concrete surface. We used both unfilled and filled (with carbon black) styrene butadiene (SB) rubber and have varied the temperature from −10 °C to 100 °C and the sliding velocity from 1 μm/s to 1000 μm/s. We find that the experimental data at different temperatures can be shifted into a smooth master-curve, using the temperature-frequency shifting factors obtained from measurements of the bulk viscoelastic modulus. The experimental data has been analyzed using a theory which takes into account the contributions to the friction from both the substrate asperity-induced viscoelastic deformations of the rubber, and from shearing the area of real contact. For filled SB rubber the frictional shear stress σ_f in the area of real contact results mainly from the energy dissipation at the opening crack on the exit side of the rubber-asperity contact regions. For unfilled rubber we instead attribute σ_f to shearing of a thin rubber smear film, which is deposited on the concrete surface during run in. We observe very different rubber wear processes for filled and unfilled SB rubber, which is consistent with the different frictional processes. Thus, the wear of filled SB rubber results in micrometer-sized rubber particles which accumulate as dry dust, which is easily removed by blowing air on the concrete surface. This wear process seams to occur at a steady rate. For unfilled rubber a smear film forms on the concrete surface, which cannot be removed even using a high-pressure air stream. In this case the wear rate appears to slow down after some run in time period.     

A Comparative Study of the Dynamic-Mechanical Properties of Styrene Butadiene Rubber/Epoxidized Natural Rubber Dual Filler Nanocomposites Cured by Sulfur or Electron Beam Irradiation

The properties of (50/50?wt%) styrene butadiene rubber/epoxidized (50%) natural rubber (SBR/ENR50) blends containing nanoclay (NC, 5 or 10phr) without and with carbon black (CB 20phr) cured by sulfur or by electron beam (EB) irradiation (50 and 100kGy), were compared. A sulfur cured compound containing 35phr CB was prepared as a reference sample. Dynamic mechanical thermal analysis (DMTA) indicated that the sulfur cured sample containing 10phr NC and 20phr CB and the 100kGy irradiated sample with 5phr NC and 20phr CB had higher crosslink density, storage modulus, and tensile strength, and less loss factor and loss modulus, compared to the reference sample. Scanning electron microscopy (SEM) images of cryo- fractured surfaces confirmed the DMA and crosslink density results. We suggest a light weight 100kGy irradiated sample containing the lowest amount of NC and 20phr CB with a uniform distribution of the –C–C– bonds crosslinks, for high thermal stability applications and also for passenger cars tire treads, for its ice grip and wet skid properties especially for icy and wet roads, with improvements of 23% and 20%, respectively as compared to the reference sample.     

Effect of Rubber Content of ABS on the Mechanical Properties of ABS/Clay Nanocomposites

One approach to improve the impact strength of acrylonitrile–butadiene–styrene (ABS)/clay nanocomposites is to increase rubber content. To investigate the effect of the rubber content of ABS on the mechanical properties of the ABS/clay nanocomposites, other parameters were fixed and ABS/clay nanocomposites containing various rubber contents were prepared in this study. Also the effect of the UV stabilizer on the mechanical properties of ABS/clay nanocomposite was studied. For addition of 3 wt% clay, ABS nanocomposite with 35 wt% content of rubber displayed the highest reinforcement ratio for tensile properties and impact strength.     

The Characterization of Pyrolytic Carbon Black Prepared from Used Tires and Its Application in Styrene–Butadiene Rubber (SBR)

The pyrolytic carbon black (PCB) made from used tires was used in styrene‐butadiene rubber (SBR). The basic properties of PCB were characterized. The effects of PCB on the processing properties of SBR compounds and the mechanical properties of vulcanizates were investigated and compared with other traditional fillers. The results showed that the chemical composition of PCB was mainly C, O, S, Zn and Si. The content of ash wa as much as 13.3%. The SEM photos showed that the primary particle size of PCB was smaller than that of N774, but the aggregate size was larger than that of N774. The effect of PCB on the processing properties of SBR compounds was similar to that of other fillers. The reinforcing effect of PCB was similar to that of N774, but inferior to that of N330.