溶胶—凝胶法制备高强度二氧化硅增透膜的研究

以正硅酸乙酯（ＴＥＯＳ）为原料，用溶胶－凝胶（ＳＯＬ－ＧＥＬ）法在碱性催化条件下制睾一氧化硅膜，经氨气氛和热处理工艺，提高了二氧化硅透膜的拭和抗氙灯辐照能力，可用于激光器泵浦光学元件的增透。在５７０－８００ｎｍ范围内，双面涂的Ｋ９下班的平均透过率可提高到９８％以上。     

有机染料DI在不同的凝胶体系中的光谱特性

分别以正硅酸乙酯（ＴＥＯＳ）和有机改性硅酸盐ＫＨ５６０－ＫＨ５５０凝胶体系为基质，为用溶胶－凝胶工艺，成功地将有机染料ＤＩ到上述基质中，通过对染料ＤＩ在不同凝胶材料中的孔结构分析，吸收光谱以及荧光光谱方法的分析，发现以ＫＨ５６０－ＫＨ５５０凝胶体系为基质的材料对染料的光学性质更为有利。     

溶胶-凝胶工艺制备香豆素掺杂SiO_2凝胶及其荧光特性研究

本文用溶胶－凝胶工艺制备了有机染料香豆素（ｃｏｕｍａｒｉｎ）掺杂ＳｉＯ２凝胶。观察分析了水解过程中的分相与凝胶干燥过程的开裂现象。通过改变反应条件以及引入添加剂，避免了分相与开裂现象，制备出尺寸约为２０×２０×１０ｍｍ完整透明的香豆素掺杂ＳｉＯ２凝胶。用差热分析和红外光谱研究了凝胶的结构和热性能。测定了凝胶的荧光激发光谱和发射光谱     

热核表面能的Thomas－Fermi统计模型理论

用Ｓｅｙｌｅｒ－Ｂｌａｎｃｈａｒｄ动量相关非定域相互作用的含温Ｔｈｏｍａｓ－Ｆｅｒｍｉ统计理论，对半无穷大核物质模型计算了核物质表面能系数σ（Ｔ，δ）随温度Ｔ和不对称度δ的变化，发现在低温Ｔ≤５ＭｅＶ和不对称度δ≤０．２时，可以近似写成σ（Ｔ，δ）＝σ０（Ｔ）［１＋Ｋ（Ｔ）δ２］，其中σ０（Ｔ）和Ｋ（Ｔ）可以拟合成温度Ｔ的二次函数．     

Ni（II）与壳聚糖的配位作用及其催化性质的研究

用ＥＳＲ、ＸＰＳ、ＩＲ、ＵＶ－Ｖｉｓ、ＤＴＡ－ＴＧ和电导率法研究Ｎｉ（Ⅱ）与壳聚糖（ＣＳ）的配位作用、所形成的配位聚合物（配聚物）的组成和结构。确定Ｎｉ（Ⅱ）与ＣＳ分子以配位键相结合形成高自旋Ｎｉ－ＣＳ配聚物，配聚物的配位单元由１个Ｎｉ（Ⅱ）与３个ＣＳ单体单元的氨基Ｎ原子和仲羟基Ｏ原子形成扭曲的六配位的八面体结构所组成。此外，对Ｎｉ－ＣＳ配聚物与Ｎａ２ＳＯ３体系在ＭＭＡ聚合中的催化性质进行了研究。     

溶胶-凝胶法制备掺Er~(3+)玻璃及其光谱性质

本文描述了用溶胶－凝胶法制备掺Ｅｒ３＋的ＳｉＯ２干凝胶和玻璃，用差热分析（ＤＴＡ）和ＦＴＩＲ研究了干凝胶和玻璃的性质，测定了掺Ｅｒ３＋凝胶和玻璃的吸收光谱和荧光光谱。     

同轴TEM-矩形TE10模式变换器的优化设计

用ＨＦＳＳ软件和网络理论对Ｓ波段同轴ＴＥＭ－矩形ＴＥ１０模式变换器进行了优化设计。同轴波导工作于过模状态,可同时传输ＴＥＭ、ＴＥ１１、ＴＥ２１模。模式变换器可应用于高功率微波的能量提取系统,优化设计方法可用于通过短路活塞来实现调配的同轴－矩表、圆波导－矩形的模式变换器。     

用多重网格TVD－LW格式数值求解N－S方程

用多重网格ＴＶＤ－ＬＷ格式数值求解Ｎ－Ｓ方程刘建军，蒋洪德（中国科学院工程热物理研究所北京１０００８０）关键词：ＴＶＤ－ＬＷ格式，Ｎ－Ｓ方程一、前言用时间推进法数值求解雷诺平均Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程，不仅能够模拟从低亚音速到高超音速的复杂定常...     

应变层异质结ZnS/ZnSe、ZnS/ZnS_xSe_(1-x)和ZnSe/ZnS_xSe_(1-x)价带带阶的研究

采用基于原子球近似下线性Ｍｕｆｉｎ－Ｔｉｎ轨道（ＬＭＴＯ－ＡＳＡ）的平均键能计算方法，研究了以ＺｎＳｘＳｅ１－ｘ为衬底，沿（００１）方向外延生长的应变层异质结ＺｎＳ／ＺｎＳｅ、ＺｎＳ／ＺｎＳｘＳｅ１－ｘ和ＺｎＳｅ／ＺｎＳｘＳｅ１－ｘ的价带带阶值ΔＥｖ（ｘ）．研究表明，ΔＥｖ（ｘ）值随衬底合金组分ｘ单调变化．且两者的关系是非线性的．在此计算结果与其它理论计算和实验结果符合较好．     

富勒烯在SiO_2与SiO_2－TiO_2凝胶中的掺入及光谱特性研究

本工作以ＳｉＯ_２和ＳｉＯ_２－ＴｉＯ_２凝胶体系为基质，选择合适的溶剂，采用特定的溶胶一凝胶工艺，成功地将纯的Ｃ_（６０）和Ｃ_（６０）／Ｃ_（７０）混合物分别均匀掺入上述基质中．研究了吸收与荧光光谱特性．室温下观测到峰置位于６６０ｎｍ附近的较强荧光带．对上述光谱性质作了初步的解释．     

干凝胶粒子物性对空心玻璃微球炉内成球过程的影响

为实现干凝胶法制备惯性约束聚变靶用空心玻璃微球(HGM)炉内成球工艺过程的有效控制,从数值模拟和工艺实验两个方面研究了干凝胶粒子直径、比热容、发泡剂质量分数和辐射吸收系数对干凝胶粒子炉内成球过程及最终HGM性能参数的影响。结果表明,随着干凝胶粒子直径和/或比热容的增大,干凝胶粒子在吸热封装阶段的升温速率显著降低,在炉内成球过程各工艺阶段的停留时间快速下降,尤其是在精炼阶段的停留时间急剧缩短。降低干凝胶粒子的比热容和/或提高干凝胶粒子的发泡剂质量分数,HGM的直径和壁厚均匀性增大,高质量空心球的比例也相应提高。干凝胶粒子的辐射吸收系数变化对炉内成球过程几乎没有影响。     

液体火箭有机凝胶喷雾液滴蒸发模型及仿真研究

凝胶推进剂虽然兼具有液体推进剂流量可控和固体推进剂长期可储存等优点, 但凝胶喷雾液滴蒸发燃烧问题却一直困扰着凝胶推进剂研制及燃烧室设计工作, 阻碍了凝胶推进剂实际工程应用.设计实现了凝胶单液滴蒸发燃烧实验系统, 通过某型有机凝胶偏二甲肼(UDMH)单液滴在四氧化二氮蒸气中的蒸发燃烧实验现象, 进一步深入分析了凝胶液滴蒸发燃烧机理.根据实验中凝胶单液滴在不同阶段的蒸发特性, 建立了有机凝胶喷雾液滴在胶凝剂膜形成、膨胀、破裂三个不同蒸发阶段的多组分蒸发模型, 采用初步选定的模型参数及物性参数对凝胶单液滴在高温气体环境中的蒸发全过程进行了仿真计算, 并与常规液体液滴的仿真结果进行了对比分析.结果表明,凝胶喷雾液滴表面胶凝剂含量在蒸发初期增加比较缓慢, 但在某临界时刻后的极短时间内迅速升高至形成胶凝剂膜的质量分数95%, 导致表面质量流率迅速下降至0,表面温度则快速上升至UDMH推进剂沸点.胶凝剂膜形成后, 液滴半径及表面UDMH蒸气质量分数出现了实验现象中凝胶液滴反复膨胀-破裂的震荡现象, 液滴表面温度维持在略高于沸点的某温度范围内,凝胶液滴内部的沸腾蒸发明显强于液体液滴表面稳态蒸发流率, 使得凝胶喷雾液滴生存时间小于常规液体液滴.     

Preparation,Characterization and Coreflood Investigation of Polyacrylamide/Clay Nanocomposite Hydrogel System for Enhanced Oil Recovery

The synthesis and characterization of polyacrylamide/clay nanocomposites for the development of hydrogel system used in enhanced oil recovery is described. The synthesized nanocomposite copolymer was crosslinked with Chromium (III) acetate to form the hydrogel which exhibited an acceptable gel strength, gelation time and gel stability. The nanocomposite gels prepared with low crosslinker concentration (2000 ppm chromium acetate) showed higher gel strength and required longer gelation time than the conventional polyacrylamide (PAAm) gel; these are desirable properties for the effective placement of gel during enhanced oil recovery operations. The effects of various parameters, such as polymer and crosslinker concentration, on the gelation time and gel strength were evaluated using the bottle testing method. X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM) revealed the formation of intercalated and exfoliated clay morphologies. The effects of the clay content on the thermal stability and gel strength of the gel network were also investigated by thermogravimetric analysis (TGA) and rheological measurements (oscillatory time sweep profiles), respectively. Also, in-situ gelation and core flooding experiments revealed that a significant permeability reduction of the sand pack cores could be achieved at reservoir conditions when they were treated with the developed nanocomposite gel formulation. Hence, this nanocomposite gel system with low crosslinker concentration (10,000 ppm of nanocomposite polymer concentration containing 2000 ppm of clay with 2000 ppm chromium acetate crosslinker) may be suitable in water shut-off treatments required for enhanced oil recovery from the oil fields.     

吸附制冷中硅胶吸附性能衰减特性研究

理论分析了导致硅胶吸附性能衰减的可能原因,并根据硅胶在吸附制冷中可能遇到的环境条件,制造了多个试样,通过实验的方法表征了这些试样的比表面积、硅羟基含量以及吸附量等参数,获得了等温吸附曲线。根据数据比较的结果,硅胶吸附性能受多种因素影响,其中粉尘等杂质污染因素是导致硅胶吸附性能降低的重要原因之一。另外,对酸泡、洗涤方法处理衰减试样吸附性能进行了探索性的研究,对恢复硅胶吸附性能的方法进行了尝试。     

聚丙烯酰胺衍生物凝胶体系的合成与光谱表征

采用聚丙烯酰胺直接氮烷基化的方法,在PAM的侧链上引入了烯丙基,通过自由基引发交联并水解,合成了聚丙烯酰胺自由基交联的弱凝胶,并研究了其结构、凝胶形成过程以及NaCl浓度对凝胶表观粘度的影响。结果表明：交联比的改变,对交联时间、破胶时间和凝胶强度均有影响,随着交联比的增大,交联时间减少,凝胶强度略有增大;聚丙烯酰胺衍生物交联体系的表观粘度随着NaCl质量浓度的增加而增加,具有良好的抗盐性能。     

琼脂糖凝胶/纳米金复合结构的制备及其表面增强拉曼性质

以琼脂糖凝胶为模板,将预先制备好的胶体金颗粒负载在琼脂糖凝胶的网状结构中,制备了琼脂糖凝胶/纳米金复合膜结构,采用透射电子显微镜、扫描电子显微镜、紫外-可见-近红外光谱仪对复合膜的结构和光学性质进行了表征,实验数据表明纳米金颗粒均匀的分散在琼脂糖凝胶膜上,并且呈现出优异的光学吸收特性。基于琼脂糖凝胶的溶胀收缩特性和纳米金颗粒可调的表面等离子体共振吸收特性,将琼脂糖凝胶/纳米金复合膜作为表面增强拉曼(SERS)基底材料,研究了其对拉曼信号分子尼罗蓝A(NBA)的SERS检测效果。结果表明,琼脂糖凝胶的多孔网状结构为纳米金颗粒的富集提供了良好的载体,随着琼脂糖凝胶在空气中失水收缩,纳米金颗粒间距离逐渐缩短,产生动态的热点效应,对拉曼信号分子具有良好的增强效应。     

Low oil emulsion gel stabilized by defatted Antarctic krill (Euphausia superba) protein using high-intensity ultrasound

Emulsion gels with low oil contents have been continuously developed in recent decades. In this study, the use of high-intensity ultrasound for the preparation of low oil emulsion gel (oil fraction of 0.25) was investigated. Specifically, defatted Antarctic krill protein (dAKP) was used to stabilize the interface of soybean oil and water. Then, the microstructure and the stabilization mechanism of the formed emulsion gel were evaluated by cryo-SEM, CLSM, zeta potential, rheological measurements, and FTIR. Besides, the particle diameter was measured to be around 5 μm. The results of CLSM indicated that the emulsion gel was the oil-in-water type. The emulsion gel exhibited gel-like viscoelastic behavior even at a low concentration of dAKP due to the formation of a rigid particle network while the rheological behavior of the emulsion gel was significantly affected by the concentration of dAKP. The stabilization of the emulsion gel can be maintained by space steric hindrance and hydrophobic interactions between particles in the emulsion gel system.     

Improving the gel properties of duck egg white by synergetic phosphorylation/ultrasound: Gel properties,crystalline structures,and protein structure

To improve the gel properties of duck egg white gel and increase the industrial value of duck egg white, the mechanisms of ultrasound and synergetic phosphorylation/ultrasound treatments were examined in this study. It was found that as the ultrasound power increased, the surface hydrophobicity, hardness, and cohesiveness of the gel system increased, and the ζ-potential and water mobility decreased. Of the two treatments, phosphorylation/ultrasound had the strongest impact on the conformation and crystallinity of the gel system and promoted the formation of high molecular polymers. Both gel systems displayed enhanced compactness, stability, and gel strength because of the enhanced protein–protein interactions via hydrogen bonds and protein aggregation, and increased the content of intramolecular β-sheets following ultrasound treatment, and synergetic phosphorylation/ultrasound further improved the stability, water binding and gel properties. This experiment showed that ultrasound and, particularly, phosphorylation/ultrasound are effective methods to improve the gel properties of duck egg white. This study enhanced our understanding of the interactions of sodium pyrophosphate and egg white under ultrasound treatment, and promote the potential application of sodium pyrophosphate and ultrasound treatment of novel food products.     

Preparation and Characterization of Biopolymers Chitosan/Alginate/Gelatin Gel Spheres Crosslinked by Glutaraldehyde

Twelve different samples of gel spheres were prepared from the biopolymers chitosan, alginate, and gelatin via polyion complex formation in aqueous solution with crosslinking by glutaraldehyde. Dropwise addition of a chitosan/gelatin solution into a solution containing alginate and glutaraldehyde gave the gel spheres. The effects of different ratios of glutaraldehyde (0.25%, 0.50%, 1.0%, and 2.0%), and gelatin (2.5%, 5.0%, and 10.0%) on the characteristics of the gel spheres were evaluated. An increase in the concentration of the glutaraldehyde led to forming true spheres in rigid form. By scanning electron microscopy (SEM), the gel spheres showed fibrous network propagation along the gel membrane surface. Fourier transform infrared (FT-IR) spectroscopy confirmed the crosslinking of the amino groups by the glutaraldehyde and the presence of crosslinking bonds between the amino groups of chitosan and the carboxyl groups in the alginate molecule. Swelling studies showed that increasing the degree of crosslinking increased the density of the polymer network, which led to a decrease in the degree of swelling. The characteristics of the gel spheres will be useful for immobilization and prolonged release of biologically active substances.     

酞菁氯镓复合凝胶玻璃的谱学性能研究

采用溶胶-凝胶(Sol-Gel)湿化学工艺将酞菁氯镓(GaPcCl)掺入二氧化硅(SiO₂)凝胶玻璃基质,制备出均匀掺杂的GaPcCl复合凝胶玻璃,并对复合体系的红外光谱(IR)、紫外-可见吸收光谱(UV-Vis)及荧光光谱等谱学性能进行了测试。结果表明：GaPcCl的掺杂对凝胶玻璃基质的红外光谱没有产生显著影响;掺杂GaPcCl在复合体系中二聚体吸收峰的强度较其DMF溶液有所增大;掺杂GaPcCl在复合体系中荧光强度随浓度的增加远大于DMF溶液。