Anticorrosion of WO₃-Modified TiO₂Thin Film Prepared by Peroxo Sol-Gel Method

The aim of this study was to develop a method to prepare WO3-TiO2 film which has high anticorrosion property when it was coated on type 304 stainless steel. A series of WO3-modified TiO2 sols were synthesized by peroxo-sol gel method using TiCl4 and Na2WO4 as the starting materials. TiCl4 was converted to Ti(OH)4 gel. H2O2 and Na2WO4 were added in Ti(OH)4 solution and heated at 95°C. The WO3-TiO2 sol was transparent, in neutral (pH^7) solution, stable suspension without surfactant, nano-crystallite and no annealing is needed after coating, and very stable for 2 years in stock. WO3-TiO2 sol was formed with anatase crystalline structure. These sols were characterized by XRD, TEM, and XPS. The sol was used to coat on stainless steel 304 by dip-coating. The WO3-TiO2 was anatase in structure as characterized by X-ray diffraction. There were no WO3 XRD peaks in the WO3-TiO2 sols, indicating that WO3 particles were very small, possibly incorporating into TiO2 structure, providing the amount of WO3 was very small. The TiO2 particles were rhombus shape. WO3-TiO2 had smaller size area than pure TiO2. The SEM results showed that the film coated on the glass substrate was very uniform. All films were nonporous and dense films. Its hardness reached 2 H after drying at 100°C, and reached 5 H after annealing at 400°C. The WO3-TiO2 film coated on 304 stainless steel had better anticorrosion capability than the unmodified TiO2 film under UV light illumination. The optimum weight ratio of TiO2: WO3 was 100:4.

负载花色苷的抗酸性羧甲基壳聚糖凝胶微球的缓释研究

为拓宽壳聚糖基水凝胶的应用范围,构筑可食用的花色苷(ACNs)递送体系,采用反相乳液法,以玉米油为连续相,水杨醛(SA)为交联剂,制备了具有抗酸性能的载ACNs羧甲基壳聚糖(CMCS)凝胶微球(ACNs/CMCS-SA),表征了其结构和形貌,研究了其稳定性、溶胀性能和缓释性能。结果表明,ACNs/CMCSSA具有微米级粒径,表面光滑呈圆形;ACNs/CMCS-SA在酸性条件下稳定性良好,溶胀和缓释过程展现pH响应性;ACNs的释放行为符合Weibull模型,pH7和9时为扩散和骨架溶蚀复合释放机制控制,pH3和5时为菲克扩散和Case Ⅱ transport(0级-溶胀依赖性释放)联合释放机制控制。ACNs/CMCS-SA制备方法简单,过程绿色;对ACNs展现良好的胃酸保护和肠道释放性能,为环境友好型药物包封材料的开发和ACNs的应用提供了理论和实践参考。

纳米钛酸钡的制备与表征在无机化学实验教学中的应用探索

针对传统钛酸钡制备实验溶胶凝胶法反应时间过长、反应不易控制、产物杂相多且产品粒径不均匀等问题,通过更换实验溶剂,引入表面活性剂,结合低温热处理,缩减了反应时间,获得了纯度较高且平均粒径小于20 nm的超细钛酸钡纳米颗粒。本改进实验适用于本科一年级的无机化学实验教学。

Comparison of the morphology and structure of W03 nanomaterials synthesized by a sol-gel method followed by calcination^or hydrothermal treatment

Tungsten （VI） oxide （WO3） nanomaterials were synthesized by a sol-gel method using WC16 and C2HsOH as precursors followed by calcination or hydrothermal treatment. X-Ray diffraction （XRD）, scanning electron microscopy （SEM） and high resolution transmission electron microscopy （HRTEM） equipped with energy dispersive X-ray spectroscopy （EDX） were used to characterize the structure and morphology of the materials. There were significant differences between the WO3 materials that were calcinated and those that were subjected to a hydrothermal process. The XRD results revealed that calcination temperatures of 300℃and 400℃ gave hexagonal structures and temperatures of 500℃ and 600℃ gave monoclinic structures. The SEM images showed that an increase in calcination temperature led to a decrease in the WO3 powder particle size. The TEM analysis showed that several nanoparticles agglomerated to form bigger clusters. The hydrothermal process produced hexagonal structures for holding times of 12, 16, and 20 h and monoclinic structures for a holding time of 24 h. The SEM results showed transparent rectangular panicles which according to the TEM results originated from the aggregation of several nanotubes.

改进的sol-gel工艺制备细晶Ba_(0.6)Sr_(0.4)TiO_3陶瓷及其介电性能的研究

用改进的sol-gel工艺制备了细晶钛酸锶钡（Ba0．6Sr0．4TiO3，BST）陶瓷块体，研究了BST陶瓷的结晶与介电性能。在这种改进sol-gel的工艺中，用传统的固相反应煅烧形成BST粉体，经高能球磨制备BST纳米陶瓷粉体，再将一定质量的纳米粉体加入到相同化学组成的BST的溶胶液中，经普球球磨12h后，制备成悬浮性好，分散均匀的浆料。浆料可用来制备BST陶瓷，并在1200℃保温2h烧结成瓷，结果显示，BST陶瓷块体结构致密，晶粒尺寸在0．15～2μm之间。分析了样品的介电性能和晶粒尺寸对材料介电性能的影响。介电温谱显示，在0℃，100kHZ时，相对介电常数为2500，介电损耗为0．02；并且存在明显的弥散相变。

高压微射流参数对虾油凝胶构建的影响及油凝胶的应用

该文旨在研究射流压力和循环次数对构建虾油凝胶的影响,再将制备的油凝胶按不同添加比例替代复合龙虾肠中的动物脂肪。结果表明,随着射流压力从40 MPa增加至160 MPa,乳液粒径和油凝胶油损失率逐渐减小,电位绝对值和油凝胶硬度逐渐增大,射流压力为120 MPa和160 MPa时各指标无显著性差异;随着循环次数从1次增加至7次,乳液粒径和油凝胶油损失率呈现先减小后增大的趋势,电位绝对值和油凝胶硬度呈现先增大后减小的趋势,在循环次数为5次时各指标效果达到最佳,油凝胶硬度为(13.38±0.48)N,油损失率为6.30%;通过对复合龙虾肠的凝胶强度、持水性、蒸煮损失、质构、色泽、流变特性、感官品质等进行测定,对比油凝胶替代动物脂肪的4种不同比例对复合龙虾肠品质的影响。结果表明,替代比例为25%时,各项指标与对照组无显著性差异,适宜作为复合龙虾肠中动物脂肪的替代比例。

直肠用美沙拉嗪温敏凝胶的制备及质量评价

目的 制备一种具有缓释和保留性能,用于直肠给药的美沙拉嗪温敏凝胶(MZ-Gel)。方法 以胶凝温度为评价指标,采用星点设计-响应面法对泊洛沙姆407和泊洛沙姆188的用量进行优化。以Franz扩散池法进一步考察体外释药行为,得到最佳处方并对其进行质量评价。结果 MZ-Gel优化处方为P407 22.56%,P188 3.34%,胶凝温度为(32.8±0.3)℃;MZ-Gel的体外释药符合一级动力学特征,具有缓释效果;胶凝时间平均值为38.3 s,pH平均值为4.07,膨胀系数平均值为4.81%,持水率平均值为99.78%;红外表征表明,美沙拉嗪的加入并没有破坏温敏凝胶结构。结论 此方法制备工艺简单,性质稳定且具有良好的体外释药特征。

Pt/C纳米催化剂的溶胶-凝胶法制备及性能

Pt/C是目前被广泛商业化应用的氧化还原催化剂,因此对于Pt/C材料的研究仍具有较高的现实意义。介绍了采用溶胶-凝胶法制备Pt/C纳米催化剂的方法和基本原理,使用X射线衍射(XRD)对样品的晶体结构进行分析,利用透射电镜(TEM)对Pt纳米颗粒的形貌、粒径和晶面间距进行了研究,使用能量散射X射线谱(EDS)分析了样品的成分,利用X射线光电子能谱(XPS)分析了材料表面的元素组成和化学价态。从实验结果看,使用溶胶-凝胶法所制备的Pt/C纳米材料,具有粒径小(平均粒径2.85nm),分布均匀,分散度高和表面含有较多吸附羟基氧物种等特点。合成路线具有反应条件容易控制,过程简单和生产成本低等优点。

马来酸阿塞那平微乳凝胶剂的制备及经鼻入脑的靶向性研究

目的 制备马来酸阿塞那平微乳凝胶剂(ASPM-Emulgel),并通过鼻腔给药评价其脑靶向性。方法 根据马来酸阿塞那平(ASPM)在不同种类油、乳化剂和助乳化剂中的平衡溶解度以及辅料相容性结果确定马来酸阿塞那平微乳(ASPMEmul)的处方组成及用量,并以卡波姆940作为凝胶基质将ASPM-Emul制备成凝胶剂;考察ASPM-Emul的粒径分布及微观形态,通过Franz扩散池法比较ASPM-Emul与ASPM-Emulgel的体外释放速率以及在羊鼻黏膜的渗透性;采用在体蟾蜍上颚模型法考察ASPM-Emulgel的鼻腔纤毛毒性;评价ASPM-Emulgel经大鼠鼻腔∶给∶药的脑靶向性。结果根据平衡溶解度和相容性结果,选择单亚油酸甘油酯、吐温80和二乙二醇单乙基醚分别作为ASPM-Emul的油相、乳化剂和助乳化剂,配比为4为淡蓝色半透明状微乳液,粒径为(73.6±7.4)nm,在透射电镜下可观察到微乳呈规则球形,均匀分散;体外释放及渗透结果显示,ASPM-Emul的释药速率较快,ASPMEmulgel释药速率持续平缓,但两者在羊鼻黏膜中的渗透率基本一致;ASPM-Emul和ASPM-Emulgel对蟾蜍鼻腔纤毛无明显毒性;与尾静脉ASPM组相比,ASPM-Emul和ASPM-Emulgel经鼻腔给药后在大脑中的药物含量显著增高,均表现出明显的脑靶向性,且ASPM-Emulgel的脑靶向效率更高。结论 将ASPM制备成微乳凝胶剂,经鼻腔给药后可以显著提高药物的脑靶向性,有望提高马来酸阿塞那平的临床治疗效果。

琼脂糖微球凝胶制备、物理化学特性及其注射效果

为了解决目前市面上填充剂填充周期短以及注射风险高的问题,以琼脂糖为原料,采用乳化固化法制备出粒径均匀的琼脂糖微球凝胶,并探讨了上述微球凝胶的物理化学特性,评价其作为面部注射填充凝胶的可行性。在高频作用下,进行琼脂糖水溶液与油相的双相均质,得到小粒径琼脂糖微球,碱性条件下与固化剂进行固化反应得到可注射琼脂糖微球凝胶。利用平均粒径在25~40μm之间的小粒径微球进行凝胶制备,正交试验确认反应温度50℃,水浴振荡速率150 r/min,反应时间8 h为最优制备工艺。在30 mm/min条件下检测得到凝胶最大推挤力小于20 N,粘弹性测试结果表明凝胶形成了较为稳定的三维网络结构。同时,细胞毒性和家兔皮下植入后局部反应证明该凝胶作为填充剂具有良好的生物相容性,且降解速率慢,较透明质酸钠凝胶具有更长的填充周期。综合表明,琼脂糖微球凝胶作为一种新型的注射凝胶有望应用于整形美容领域。

SiO_2 Aerogels Prepared with Ambient Pressure Drying and Its Properties

SiO2 aerogels were produced from tetraethyl orthosilicate （TEOS） as silicon resources,ethanol as solvent and watery HCl or ammonia by sol-gel method and surface modification at ambient pressure.Scanning electronic microscopy,Fourier transform infrared spectrometer （FT-IR）,pore size distribution measurement,packing density and some other experiment methods were used to characterize the morphology and pore structure and other properties of the silica aerogels.The results show that the silica aerogels have a typical nano-porous microstructure with hydrophobic property.It was discovered that SiO2 aerogels have better properties when the preparation condition is as following the watery HCl concentration is 1%,the aging reagent is CH3CHOHC4H9,the aging time is 20 d,the volume concentration of trimethylchlorosilane （TMCS） in hexane is 6% and the surface modification time is 24 h.

在含二氧化硅的介电基体表面制备碳纳米材料的研究进展

碳纳米材料作为21世纪的明星材料,具有优异的光、电与力学性能。其制备过程中需要金属基底进行沉积与催化,然后将制备的碳纳米材料从金属基底转移到含SiO_(2)的介电基体进一步构筑电子器件。但在转移过程中会引入碳纳米材料的褶皱、破损等结构缺陷,以及金属和试剂残留,造成电子器件性能下降。因此,直接在含SiO_(2)介电基体表面制备碳纳米材料具有重要意义。总结了近年在含SiO_(2)介电基体表面制备碳纳米材料的研究进展,阐述了金属扩散-析出法、化学气相沉积法、分子束外延生长法等多种制备手段;介绍了石英玻璃、玻璃纤维两种主要含SiO_(2)介电基体生长碳纳米材料的特点与性能,并提出了在含SiO_(2)介电基体表面制备碳纳米材料的研究难点与趋势。

层层自组装在涤纶织物阻燃整理上的应用

为解决涤纶易燃和燃烧熔滴现象,开发阻燃涤纶纺织品,总结了层层自组装法在涤纶织物阻燃整理方面的相关研究。对国内外涤纶织物层层自组装法阻燃整理的研究现状进行了梳理,包括非膨胀型阻燃涂层和膨胀型阻燃涂层。概述了层层自组装与其他后整理技术的应用。总结和展望了层层自组装在涤纶阻燃整理上的研究。指出:研究多功能型、耐久型、绿色环保型、高效的层层自组装方法是今后的技术突破和发展方向。

Dual-Wavelength Laser Flash Raman Spectroscopy Method for In-Situ Measurements of the Thermal Diffusivity: Principle and Experimental Verification

This paper presents an in-situ, non-contact, non-destructive "dual-wavelength laser flash Raman spectroscopy method" for measuring the thermal diffusivity. In this method, a heating pulse is used to heat the sample and another pulsed laser with a different wavelength and negligible heating effect is used as a probe to measure the sample temperature changes during the heating and cooling periods from the Raman peak shifts. The sample temperature rise and fall curves are measured by changing the delay between the heating pulse and the probing pulse with the thermal diffusivity then characterized by fitting the temperature curves. The time delay between the heating and probing pulses can be precisely controlled with a minimum step of 100 ps. Hence, the temperature variation can be scanned with an ultra-high temporal resolution of up to 100 ps, which significantly improves the measurement accuracy of transient thermal parameters. The measurement accuracy of this method has been verified using a bulk material model and experiments. The measured thermal diffusivity of a silicon sample has been obtained to be 8.8×10^(-5 )m^2/s with a 3% difference between the measured value and the average result for bulk silicon in the literature which verifies the reliability and accuracy of this method.

羟基磷灰石的合成及应用研究进展

羟基磷灰石(HAP)在替代性骨材料、骨组织工程等领域被广泛应用,同时也在抗菌、药物传输载体、吸附、催化、柔性耐火材料等生物医学、功能复合材料领域具有广泛应用前景。本文介绍了5种不同的HAP合成方法,可以制备出不同结构的HAP,以满足不同的应用需求。全面了解HAP的合成方法、结构特点和应用研究现状,有助于在HAP的功能拓展研究中,制定合理的研究方案,对其他类似的材料开发和应用研究也具有借鉴意义。

维生素A棕榈酸酯原料细菌内毒素检查方法研究

目的:建立维生素A棕榈酸酯细菌内毒素检查法质量标准。方法:维生素A棕榈酸酯以98%乙醇为溶剂溶解,再用细菌内毒素检查用水稀释制成乳浊液,依照《中国药典》2020年版(四部)1143细菌内毒素检查法,对维生素A棕榈酸酯细菌内毒素检查法进行干扰试验预试验和干扰试验,同时增加细菌内毒素回收干扰试验预试验和干扰试验。结果:维生素A棕榈酸酯在实验过程中出现的复析、乳浊现象对细菌内毒素检查无影响,维生素A棕榈酸酯在0.015625 mg·mL^(-1)浓度下对细菌内毒素检查无干扰作用。两个不同厂家各3批维生素A棕榈酸酯的细菌内毒素检查结果符合规定。结论:本法可用于维生素A棕榈酸酯细菌内毒素的质量控制。

溶胶-凝胶法制备纳米粉体

介绍了溶胶-凝胶法的原料、原理以及无机盐和金属醇盐的水解特点以及溶胶-凝胶方法的最新进展、存在的问题,并结合作者自己的研究工作,以二氧化锡为例,介绍了溶胶-凝胶法的工艺流程。最后对溶胶-凝胶法的未来发展进行了展望。

溶胶-凝胶法合成纳米材料研究进展

溶胶-凝胶法具有反应条件温和、结晶度好且分散度高的优点,与旋涂法、金属掺杂法等工艺配合使用可以改变纳米材料形貌,改善产品特性,克服传统方法的局限性,使纳米材料适应面更广,品质更优良。综述了溶胶-凝胶法在零维、一维、二维、三维纳米材料合成中的研究现状及发展趋势。介绍了近年来纳米材料的合成方法、阐明了作用原理并分析了溶胶-凝胶法合成纳米材料的优越性,最后对溶胶-凝胶法发展前景进行了展望。

纳米二氧化钛纤维的制备及其光催化活性

以钛酸丁酯为钛源,用溶胶乳化凝胶技术合成了纳米TiO2粉末,将其置入碱溶液中进行回流处理得到了纳米TiO2纤维。用X射线衍射和透射电镜对纳米TiO2的晶型和表面形貌进行表征。结果表明:当氢氧化钠溶液的浓度为10mol/L时,所制备的纳米TiO2纤维直径为10～15nm,纤维长径比为20～25。TiO2纤维在750℃热处理后发生由锐钛矿相向金红石相的转变。光催化降解亚甲基蓝的实验显示:未经热处理的TiO2纤维的光催化活性比纳米TiO2粉末的差,而经500℃热处理后的TiO2纤维光催化活性最强,在紫外光照射4h后,亚甲基蓝降解率达92%。当热处理温度进一步升高后,TiO2纤维光催化活性反而降低。