利用标志法研究钒—硅酸锆蓝色颜料的生成机理

标志法用来研究钒-硅酸锆蓝色颜料形成过程中的离子移动问题，借此了解该颜料的生成机理。结果表明Si^4 和Zr^4 中Si^4 是唯一可以移动的离子；NaF的加入有利于SiO2的玻璃化，因而对硅离子的迁移有一定贡献，但其移动更依赖于NaF和NH4VO3反应所形成的液相。此外，ZrO2的溶解也是硅酸锆生成的一个限制因素。     

Synthesis of Metal Oxides@C (Metal =Ni,Fe) Based Prussian Blue Analogs as a High-performance Anode Material for Lithium-ion Battery

Ni3[Fe(CN)6]2 nano-cubic precursors were prepared by chemical coprecipitation at room temperature with nickel acetate and potassium ferricyanide as raw materials.The corresponding NiFe2O4-NiO@C composites with excellent crystallization were prepared by two-stage oxidation at low temperature.The microstructure and electrochemical behavior of the materials showed that the Prussian blue analog was transformed into metal oxide while the carbon coating was maintained in the two-stage oxidation at low temperature.The existence of the carbon coating reduces the charge transfer impedance to 31.5 Ω.At the current density of 500 mA/g,the reversible capacity of 632.7 mAh/g is maintained after 500 cycles.At the same time,carbon cladding can also enhance the role of pseudocapacitance in the material.At the scanning rate of 0.1 mV/s,the pseudocapacitance account for 54.4％ of the total discharge capacity,which is significantly higher than that of uncoated materials.     

无游梁式抽油机框架结构在地震谱作用下的响应分析

以WCYJK14-7-53Z型无游梁式抽油机为研究对象,应用有限元法对其进行了地震谱作用下的动力响应分析。首先建立该抽油机框架结构的有限元模型和编制II类场地8度烈度下的地震反应谱,分别进行了模态分析和地震谱分析,然后对该抽油机结构进行动强度验算,得出该结构满足动强度要求。     

浊点萃取-光度法测定卷烟纸中磷酸盐

建立了分光光度法测定卷烟纸中痕量磷酸盐的浊点萃取分离富集体系。磷酸根离子在酸性介质中与钼酸盐反应生成磷钼酸盐,可溶性磷钼酸盐与阳离子表面活性剂溴化十六烷基三甲基铵(CTAB)形成疏水性的离子对缔合物,进行浊点萃取,采用光度法测定。研究了溶液的酸度、试剂用量、平衡时间、平衡温度、干扰离子对浊点萃取效果的影响,并得到最佳测定条件:5%的Triton X-114用量0.8m L、平衡温度60℃、平衡时间15min,将表面活性剂富集相用乙醇分散稀释,应用紫外-可见分光光度计在700 nm波长处测定。测定的线性范围为5.0~500 ng/m L,方法的检出限为0.5ng/m L,相对标准偏差(RSD)为1.1%~3.5%。     

氨基改性的MCM-41吸附水溶液中亚甲基蓝的研究

用3-氨丙基三甲氧基硅烷对MCM-41进行改性,得到MCM-41-NH2吸附剂,用X射线衍射(XRD)、氮气吸附脱附、透射电镜(TEM)和红外光谱对其进行表征。并将其用于去除水溶液中亚甲基蓝(MB)的吸附研究,探讨了吸附剂量、溶液p H、温度和接触时间对亚甲基蓝吸附的影响。结果表明,MCM-41-NH2对亚甲基蓝的吸附是一个吸热过程。吸附等温线符合Langmuir等温吸附模型,吸附动力学符合拟二级动力学模型。     

一种平面Pd(Ⅱ)配合物的合成结构以及光催化性质的研究

配合物[Pd(dmphen)CO3]·H2O(dmphen是2,9-二甲基-1,10-菲咯啉)已合成和表征。钯配合物是采用水热合成法制备的,利用X射线单晶衍射法、元素分析、红外等方法对其进行表征。本文以亚甲基蓝(MB)为探针进行了光催化反应对其进行降解,测评了[Pd(dmphen)CO3]·H2O配合物的光催化降解活性。结果表明,在300 W氙灯光源照射下,该配合物对亚甲基蓝光的催化降解有一定效果,亚甲基蓝(MB)的光催化降解率由时间和Pd配合物的参与共同决定。     

聚丙烯酸/锂藻土纳米复合水凝胶对亚甲基蓝吸附性能的研究

研究了聚丙烯酸/锂藻土纳米复合水凝胶对染料亚甲基蓝的吸附性能,考察了不同吸附条件,包括凝胶用量、染料浓度、吸附时间及溶液p H条件等对水凝胶吸附效果的影响。实验结果表明,水凝胶对亚甲基蓝的吸附过程在30 min内即能达到平衡,吸附速度快;最大吸附容量高达1 192.9 mg/g,是普通吸附剂吸附容量的几十倍,吸附效果好;凝胶的吸附等温线拟合结果符合Freundlich模型,动力学拟合结果显示,凝胶对亚甲基蓝的吸附过程符合二级动力学模型。     

Polymeric Nanoparticle-Based Photodynamic Therapy for Chronic Periodontitis in Vivo

Antimicrobial photodynamic therapy (aPDT) is increasingly being explored for treatment of periodontitis. Here, we investigated the effect of aPDT on human dental plaque bacteria in suspensions and biofilms in vitro using methylene blue (MB)-loaded poly(lactic-co-glycolic) (PLGA) nanoparticles (MB-NP) and red light at 660 nm. The effect of MB-NP-based aPDT was also evaluated in a clinical pilot study with 10 adult human subjects with chronic periodontitis. Dental plaque samples from human subjects were exposed to aPDT—in planktonic and biofilm phases—with MB or MB-NP (25 µg/mL) at 20 J/cm² in vitro. Patients were treated either with ultrasonic scaling and scaling and root planing (US + SRP) or ultrasonic scaling + SRP + aPDT with MB-NP (25 µg/mL and 20 J/cm²) in a split-mouth design. In biofilms, MB-NP eliminated approximately 25% more bacteria than free MB. The clinical study demonstrated the safety of aPDT. Both groups showed similar improvements of clinical parameters one month following treatments. However, at three months ultrasonic SRP + aPDT showed a greater effect (28.82%) on gingival bleeding index (GBI) compared to ultrasonic SRP. The utilization of PLGA nanoparticles encapsulated with MB may be a promising adjunct in antimicrobial periodontal treatment.     

蒙脱石含量测定方法改进研究

用吸蓝量(MB)换算法测定蒙脱石含量,换算系数0.442不能用来准确计算其实际含量。由于吸蓝量和阳离子交换容量(CEC)与蒙脱石含量正相关,通过测定原矿、原矿提纯样以及提纯后杂质矿物的吸蓝量或CEC,进行加权或对比计算,即可得到原矿中蒙脱石的含量,这样可消除膨润土属性、属型等对测定结果的影响。改进的结果表明,不论加权法还是比值法,CEC也可用于测定蒙脱石含量;但加权法计算更为合理。蒙脱石、杂质矿物的纯度,以及它们的吸蓝量、CEC的精密度和准确度,是加权法测定准确与否的关键;比值法适用于细粒级或提纯后纯度较高情况下的测定。