矿物表面金属离子组分与糊精的相互作用（Ⅰ）──糊精在矿物表面的吸附

通过矿物表面糊精吸附量的测定、电动电位测定及在不同ｐＨ值下矿物表面羟基浓度的测定，系统探索了糊精在赤铁矿、金红石、方解石、萤石、重晶石、磷灰石及硅灰石等氧化矿和盐类矿物表面附吸的规律，发现糊精的吸附主要是由于与矿物表面金属羟基化合物发生了程度不同的化学作用。     

组合抑制剂对萤石与方解石浮选行为研究

萤石和方解石作为典型的含钙矿物,两者的表面物理化学性质较相似。因此方解石型萤石矿的有效分离是选矿领域的难题之一。以水玻璃、硫酸铝及两者组合成为盐化水玻璃作为萤石浮选阶段的抑制剂,通过纯矿物浮选实验进行研究,探究了这三种抑制剂对萤石和方解石抑制作用行为。试验结果表明,单一使用水玻璃或硫酸铝条件下,抑制效果不佳。而盐化水玻璃(硫酸铝∶水玻璃为2∶5)时,能有效抑制脉石方解石,实现对萤石矿的有效分离。     

矿物表面金属离子组分与糊精的相互作用（Ⅱ）──糊精在氧化矿及盐类矿物表面吸附的XPS及AES研究

借助于光电子能谱（ＸＰＳ）及俄歇电子能谱（ＡＥＳ）测试，系统地研究了糊精在氧化矿及盐类矿物表面的作用行为．发现糊精在赤铁矿、金红石、方解石和重晶石表面作用前后晶格金属元素键合状态发生了显著变化，其本质为化学作用，而糊精在萤石表面作用前后，Ｃａ的结合能及俄歇参数变化较小，化学作用较弱，更接近于氢键等物理作用。     

金红石与磷灰石浮选分离中硫酸铝的作用研究

研究表明．在FL108作捕收剂条件下，硫酸铝强烈抑制金红石而使磷灰石上浮，采用“FL108＋Al2（SO4）3”的浮选药剂制度，可实现两矿物的分离。通过分析Al3＋和金红石表面Ti4＋、磷灰石表面Ca2＋的水解特性，还阐述了Al2（SO4）3的选择抑制机理。     

复合捕收剂浮选金红石的研究

通过浮选试验以及吸附量、表面张力等的测定,研究了复合捕收剂对金红石的捕收性能。添加剂F能大大降低捕收剂B的用量,并与捕收剂B产生缔合作用吸附在矿物表面。     

萤石与重晶石浮选分离新药剂的研究

萤石与重晶石的浮选分离及药剂的作用机理研究结果表明,烷基α-羟基1.1双膦酸(TF28)是萤石和重晶石的优良捕收剂。以ND_(16)作抑制剂,可以实现萤石与重晶石的浮选分离。TF28在萤石、重晶石表面除存在化学吸附外,在重晶石表面还存在物理吸附。     

油酸钠与胲铵类药剂协同浮选金红石的机理

采用单矿物浮选试验研究了金红石在油酸钠和胲铵类药剂组合体系中的浮选行为,利用zeta电位、表面张力、接触角、紫外光谱等手段从界面化学角度详细研究了组合药剂在液液、液固界面的作用机制。结果表明：单一药剂对金红石捕收能力的大小顺序为：油酸钠(SO,51.55%)＞N-亚硝基萘胲铵(CF,18.72%)＞N-亚硝基苯胲铵(NF,14.01%)。组合药剂添加顺序对金红石回收率的影响大小为：先添加N-亚硝基苯胲铵后油酸钠＞先添加油酸钠后N-亚硝基苯胲铵＞油酸钠和N-亚硝基苯胲铵预混后再添加＞油酸钠和N-亚硝基萘胲铵预混后再添 加＞先添加油酸钠后N-亚硝基萘胲铵＞先添加N-亚硝基萘胲铵后油酸钠,该顺序与药剂之间的协同效应指数有较好的一致性。油酸钠分子中的双键与胲铵类分子中的苯环和萘环之间存在电子共轭效应,该效应对组合药剂的吸附特性及缔合行为有较大影响,药剂之间所生成缔合物的数量及空间构象是影响金红石浮选行为的主要原因。     

RGD与特定形貌金红石表面相互作用的分子动力学模拟

精氨酸-甘氨酸-天冬氨酸（Arg-Gly-Asp,RGD）序列是细胞膜整合素受体与细胞外配体相结合的识别位点,利用其对材料表面进行仿生修饰可以提高植入体的生物相容性。采用全原子分子动力学方法,模拟研究了RGD与理想和具有不同深度凹槽结构的金红石型TiO₂（110）表面的结合模式和结合稳定性。研究结果表明,在纯水环境下,RGD在金红石表面存在锚定点是该序列中带负电的羧基基团与表面Ti原子直接键合的前提。凹槽侧壁表层的不饱和原子是RGD形成吸附的潜在作用点,故在金红石表面引入凹槽结构能在一定程度上影响该序列同基底之间的结合模式。当RGD通过羧基基团与槽底原子稳定键合之后,若剩余部分的长度足以触及至槽壁区域,则肽链中带正电的氨基或胍基基团与槽壁原子形成氢键的概率较大;若RGD通过两侧末端基团分别同槽底形成了稳定作用,则会显著抑制该序列与槽壁原子之间氢键的形成。RGD序列同金红石表面结合作用的强弱取决于结合点的数量以及相互作用的具体类型。     

亚油酸钠协同二元表面活性剂体系中金红石的浮选特性及机理

利用单矿物浮选试验分别研究了金红石在亚油酸钠与油酸钠或苯甲羟肟酸钠组成的二元表面活性剂体系中的浮选行为,采用Zeta电位、表面张力、接触角、紫外漫反射吸收光谱等手段从气/液、固/液界面探讨了组合药剂之间及组合药剂在金红石表面的作用机制。结果表明,药剂添加顺序对金红石浮选行为有较大影响,亚油酸钠与苯甲羟肟酸钠的协同效应指数要高于亚油酸钠和油酸钠组合体系;组合药剂在金红石表面的吸附可分为单层诱导共吸附和缔合物多层吸附两大类,分子间的缔合作用力及缔合产物的吸附状态是影响组合药剂协同作用及金红石浮选行为的关键因素;苯甲羟肟酸钠和亚油酸钠体系中不同药剂添加顺序下金红石浮选行为与其带隙宽度的变化有较好的一致性,而油酸钠和亚油酸钠体系中则未发现明确的对应关系。     

油酸钠与苯甲羟肟酸钠协同体系中金红石的浮选机理

采用单矿物浮选实验研究了油酸钠(SO)和苯甲羟肟酸钠(BHA)组合药剂体系中金红石的浮选行为,利用Zeta电位、接触角、表面张力、紫外漫反射光谱等手段分别从固?液、液?液界面化学角度研究了组合药剂之间、组合药剂与矿物之间的作用机制以及组合药剂对金红石浮选行为的影响机理。结果表明,药剂添加顺序对金红石浮选回收率有较大影响,不同pH值下组合药剂之间有明显的正协同效应,金红石回收率及协同效应指数的大小顺序为先苯甲羟肟酸钠后油酸钠>预先混合再添加>先油酸钠后苯甲羟肟酸钠;油酸根离子中富电子的双键与苯甲羟肟酸根离子中缺电子的苯环可能发生电子共轭效应并可生成多种离子间缔合物,缔合物在金红石表面吸附时最佳空间几何构象能否形成及形成数量的多寡对药剂之间的协同效应及金红石的浮选行为具有举足轻重的影响。金红石与组合药剂作用后的漫反射光谱显示组合药剂对金红石浮选回收率与其对金红石带隙宽度的影响顺序一致。     

萤石浮选捕收剂研究进展

萤石捕收剂可分羧酸类、生物脂类、两性捕收剂 、复合捕收剂、烷基膦酸和烷基硫酸(烷基磺酸)等五类,其中绝大部分属化工厂副产品。羧酸类(油酸或油酸盐)仍然是萤石浮选的主要捕收剂。使用两性捕收剂能改善萤石-方解石分离的选择性,而生物脂类则可有效排除萤石精矿小的二氧化硅。     

Adhesion of air bubbles to a fluorite surface in the presence of oleate species

Measurements of the detachment force of air bubbles from a surface of fluorite covered with an oleate film immersed in an aqueous sodium oleate solution or water were carried out. The contact angles for the systems fluorite/oleate film-drop of aqueous sodium oleate solution-air, fluorite/oleate film-air bubble-aqueous sodium oleate solution, and fluorite/oleate film-air bubble-water were also measured. The detachment forces were also calculated from the measured contact angles. It was found that the adhesion of air bubbles to the fluorite surface increased considerably in the presence of an oleate film on the fluorite surface, but decreased if the oleate film was at the water-air interface. Good agreement between the theoretically calculated and the measured values of the detachment force for the system fluorite/oleate film-air bubble-sodium oleate aqueous solution when the concentration of this latter solution was in the range 0 to 87.1 mg/dm³ was also found, but for concentrations over 87.1 mg/dm³ the calculated values of the detachment force were higher than the measured values. The calculations and measurements indicate that the most favourable condition for the adhesion of air bubbles to fluorite grains is the presence of a chemisorbed film of oleate without surface precipitation of calcium oleate salt at low concentrations of oleate species in water.     

Exposed crystal surface-controlled rutile TiO2 nanorods prepared by hydrothermal treatment in the presence of poly(vinyl pyrrolidone)

Rutile TiO₂ particles with specific exposed crystal faces were prepared by hydrothermal treatment of titanium trichloride (TiCl₃) solution with poly(vinyl pyrrolidone) (PVP) as a shape-control reagent. Crystal phase, shape, and size of TiO₂ particles were found to be greatly dependent on the concentration of PVP in the solution. The exposed crystal surface of TiO₂ was controlled by changing the concentration of PVP in TiCl₃ and NaCl solutions. The prepared TiO₂ particles were characterized by TEM, SEM, XRD, and specific surface area measurements. The photocatalytic activity of the synthesized TiO₂ particles was evaluated by decomposition of acetaldehyde and toluene in gas phase. The synthesized TiO₂ particles showed higher photocatalytic activity for degradation of acetaldehyde and toluene than did commercial TiO₂ particles (MT-600B). However, the tendency of photocatalytic activities of the synthesized TiO₂ particles for degradation of acetaldehyde in gas phase was different from that for degradation of toluene. From the photodeposition of Pt and PbO₂, we propose that the (1 1 0) face provides reductive sites and that the (1 1 1) face provides oxidative sites. The results suggest that the crystal faces facilitate the separation of electrons and holes, resulting in improvement in photocatalytic activity.     

金红石加碳氯化的热力学

运用HSC软件对金红石构成的多元、多相、多反应的复杂体系进行还原平衡组分的计算与分析。通过热力学计算,所得的结果表明：金红石在200℃的较低温条件下可完全转化。金红石加碳氯化反应随着温度的升高和配碳量的增加,体系中CO／CO2摩尔比值增大。只要维持理论配碳量和氯气用量,金红石即可完全转化。     

Formation and crystal growth of needle-like rutile in glass- ceramics

Glass-ceramic, which has negligible dielectric loss, high mechanical strength, excellent drop resistance, low CTE, and low density for lightweight design, is the best option for the back cover of mobile devices in the 5 G era. Herein, the effect of P₂O₅ on the phase separation and crystallization of MgO–Al₂O₃–SiO₂-TiO₂ glass-ceramics is studied. The incorporation of P₂O₅ in the glass structure leads to phase separation, in which the P and Mg-enriched phase was formed in the glass matrix, and promotes the increase of T_g. With the increase of P₂O₅ content, the precipitated crystals change significantly. First, the silicate crystals (Mg₂SiO₄) disappear, whereas the phosphate crystals (LiMgPO₄) emerge when 2 mol% P₂O₅ is introduced. Second, titanate crystal (MgTi₂O₅) can not be observed when 4 mol% P₂O₅ is introduced. The Ti₅O₉ crystals appear simultaneously with LiMgPO₄ crystals and transform to rutile TiO₂ crystals at high temperature. Interestingly, the needle-like rutile TiO₂ crystals, which is 300 nm long and 20 nm wide, have been found in a glass with 4 mol% P₂O₅. The large L/D ratio of needle-like crystals increases the hardness significantly from 6.08 GPa to 7.14 GPa. Similar to other fiber reinforced composites, this needle-like crystals provide a new strategy to improve the mechanical properties of glass ceramics.     

河南某地金红石矿选矿研究

试验结果表明,选前脱泥对提高原矿品位,改善浮选环境、降低药耗和提高低品位细粒嵌布金红石的选矿回收率至为重要。试验发现,浮选药剂的选用和药剂间的组合搭配,对浮选结果影响也很大。中间试结果表明所选用的浮选工艺是合理的。     

Morphological and crystallite size impact on electrochemical performance of electrospun rutile and rutile/multiwall carbon nanotube nanofibers for lithium ion batteries

A sol–gel based route was used to produce TiO₂ based nanocomposites. Sols were electrospun into continuous nanofibers and calcined to get rutile phase. Fibers with diameter around 100 nm and crystallites size between 10 and 50 nm were obtained. The morphological impact and crystallites size dependence of the electrochemical performance for as-synthesized materials are reported. Enhancements using inert calcination atmosphere and incorporation of multi-wall carbon nanotubes (MWCNT) into the system are also presented.     

永丰萤石矿粗精矿再磨浮选新工艺研究

本文研究了萤石—石英矿石的浮选，通过试验提出了粗精矿再磨浮选新工艺，各项指标较原工艺均有较大提高。