AEO9/醇/烷/水系反相微乳液陶瓷墨水制备与性能研究

AEO₉/醇/烷/水系反相微乳液具有相当优异的溶水性能,选择该系用于陶瓷墨水制备,就醇的种类和用量对反相微乳液区的影响进行了研究,划定了该区在拟三元相图中的位置,确定了体系最佳溶水量条件.以ZrOCl₂·8H₂O和NH₃·H₂O溶液分别替代优化体系中的水,获得2个反相微乳液,再将它们混合,通过反应制得陶瓷墨水,测定分析了陶瓷墨水理化性能变化规律,针对喷射打印成型硬件要求,对二者性能匹配性进行重点考察。     

提高AEO9/醇/烷/水体系反相微乳液陶瓷墨水浓度的研究

鉴于陶瓷墨水在某些性能上存在不足,例如相对连续式喷墨打印机打印成型要求而言粘度较大、电导率偏低、固相含量不够高等问题,通过加入醇和Na₂CO₃等添加剂以及利用双连续结构分别对粘度、电导率等性能加以调整及提高陶瓷墨水的浓度。少量醇的加入(1％～2％)使陶瓷墨水体系粘度降低到11mPa·S左右,根据相图从双连续结构角度出发设计了陶瓷墨水的组成,考察了溶水量的变化,并借以提高陶瓷墨水固相含量,使其达到2.54％。由于双连续结构陶瓷墨水的理化性能(粘度、电导率等)仍不能完全满足要求,加入少量Na₂CO₃进行改性,改性后的陶瓷墨水粘度降至18mPa·s以下,电导率接近100mS/m,稳定性良好,墨水中陶瓷颗粒粒度在10nm以下,但透光率略有降低,显微结构观察表明具有明显的双连续结构特征。     

The influence of the structure and the composition of water/AOT-Tween 85/IPM microemulsion system on transdermal delivery of 5-fluorouracil

The purpose of this study was to investigate the influence of the structure and the composition of water/Aerosol-OT (AOT)-Tween 85/isopropylmyristate (IPM) microemulsion system (WATI) on transdermal delivery of 5-fluorouracil (5-FU). The structure of WATI was characterized by measuring surface tension, density, viscosity, electric conductivity, and differential scanning calorimetry. The effect of the drug loading, water content, component compositions and the amount of mixed surfactant on permeation of 5-FU through mice skin was evaluated by using Franz-type diffusion cells. The results in vitro implied that WATI was W/O microemulsion when the water content was below 20 wt% at fixed 20 wt% of mixed surfactant at 25°C, then might be transformed to a bicontinuous structure, finally, formed O/W microemulsion with water content over 30 wt%. Increase of the drug loading can directly facilitate the penetration of the drug across the skin. Drug diffusion after 12?h from the bicontinuous microemulsion (795.1?±?22.3 µg·cm^?2) would be fastest compared to that from the W/O microemulsion (650.2?±?11.7 µg·cm^?2) and the O/W microemulsion (676.6?±?14.8 µg·cm^?2). The combination of AOT and IPM could bring about synergistic effect on the skin enhancement, however, Tween 85 in WATI decreased the cumulative permeation amount of 5-FU. The content of mixed surfactant had no effect on the permeation of 5-FU at fixed surfactant/cosurfactant ratio (K_m?=?2). Thus, the increased transdermal delivery the hydrophilic drug of 5-FU was found to be concerned with both of the structure and the composition of WATI.     

Water/span80/Triton X-100/n-hexyl alcohol/n-octane microemulsion system and the study of its application for preparing nanosized zirconia

For the first time, a brand new microemulsion system (water/span80/Triton X-100/n-hexyl alcohol/n-octane) was studied and applied to prepare nanosized zirconia. In total, three types of aqueous phases (distilled water, 2.0 M ammonia solution, and 0.8 M ZrOCl₂ aqueous solution) have been studied, leading to three different ternary phase diagrams. This work indicates that such microemulsion system has two distinct advantages: on the one hand, significant improvement in the solubilization capability has been obtained (as high as 50 vol.% water content can be achieved in our case in compared with the maximum value around 30 vol.% as in previous reported ones); on the other hand, the cloudy point in our system can be manipulated in a wide range by simply adjusting the content of Triton X-100. Taking these advantages into account, we have successfully prepared nanosized zirconia utilizing this system. Furthermore, the analyses of the recorded DTA, XRD, and TEM spectroscopies have revealed that the calcination conditions are essential for the crystal growth of nanosized zirconia.     

Synthesis of polyaniline/multi-walled carbon nanotube nanocomposites in water/oil microemulsion

A water/oil microemulsion system having been successfully used for synthesizing polyaniline(PANi) nanoparticles, was employed for preparing PANi/multi-walled carbon nanotube (MWCNT) nanocomposites via in situ chemical oxidative polymerization. The structures and the electrical property of PANi/MWCNT nanocomposites were also studied. The studies showed that PANi could coat MWCNTs to form nanocables with core-shell structure, and the backbone structure of PANi was not damaged by the introduction of MWCNTs. The conductivities of PANi/MWCNT nanocomposites were higher than that of PANi. Moreover, a model was supposed to be used for describing a PANi/MWCNT nanocable formation by in situ microemulsion polymerization.     

Thermoeconomic optimization of a single effect water/LiBr vapour absorption refrigeration system

In this paper, the thermoeconomic theory is applied to the economic optimization of a single effect water/LiBr vapour absorption refrigeration system for air-conditioning application, aimed at minimizing its overall operation and amortization cost. The mathematical and numerical techniques based optimization of thermal system is not always possible due to plant complexities. Therefore, a simplified cost minimization methodology is applied to evaluate the economic costs of all the internal flows and products of the system by formulating exergoeconomic cost equations. Once these costs are determined, the system is thermoeconomically evaluated to identify the effects of design variables on costs and enables to suggest values of design variables that would make the overall system cost effective. Finally, an approximate optimum design configuration is obtained by means of sequential local optimization of the system, carried out unit by unit. The result compares this optimum with the base case and shows percentage variations in the system's operation and amortization cost.     

Selection of microemulsion composition via study of phase behavior for synthesis of stable monodisperse platinum nanoparticles and optimization of experimental parameters

ABSTRACT

Monodisperse platinum nanoparticles were synthesized by microemulsion technique. Feasibility of formation of microemulsion with chosen proportions of components is a common problem with this method. Here, prior to preparation of microemulsion for synthesis purpose, systematic study was carried to check the suitability of selected microemulsion system by establishing phase diagram for ternary system at constant temperature on triangular coordinates. Temperature dependency of microemulsion was studied by preparing phase diagram of temperature against mass fraction of aqueous phase in ternary mixture. Both these triangular coordinate diagram at constant temperature and temperature dependency plots helped to choose proper concentrations of components in the system. Effects of molar concentration of water-to-surfactant ratio, platinum salt concentration, continuous oil phase concentration, and presence of cosurfactant with surfactant on particle size were investigated for selected system of components. Synthesized platinum nanoparticles were characterized by dynamic light scattering and transmission electron microscope. Light backscattering profiles obtained by Turbiscan were used to judge the stability of microemulsions. Further, partial weightage of affecting parameters on size of synthesized particle were studied by Taguchi orthogonal array method.     

Preparation of silazane grafted yttria-stabilized zirconia nanocrystals via water/CTAB/hexanol reverse microemulsion

The nanosized precursors of yttria-stabilized zirconia (YSZ) were prepared via a water/CTAB/hexanol reverse microemulsion. The surface hydroxyl groups of the YSZ precursor were substituted by siloxyl groups using HMDS (hexamethydisilazane) as starting material. The untreated and treated YSZ powder were characterized by ultraviolet-visible-near-infrared spectrometer, FT-IR spectrometer, X-ray diffractometer, BET surface-area analyzer, and electron probe microanalysis (EPMA). After HMDS treatment, the amount of Si atom grafted on the nanoparticle surface was about 1 mol%. The crystallite size of the treated powder was smaller and the surface area was larger than the untreated powder.     

AEO9/醇/烷/水系反相微乳液陶瓷墨水制备与性能研究

AEO9/醇/烷/水系反相微乳液具有相当优异的溶水性能,选择该系用于陶瓷墨水制备,就醇的种类和用量对反相微乳液区的影响进行了研究,划定了该区在拟三元相图中的位置,确定了体系最佳溶水量条件.以ZrOCl2.8H2O和NH3@H2O溶液分别替代优化体系中的水,获得2个反相微乳液,再将它们混合,通过反应制得陶瓷墨水.测定分析了陶瓷墨水理化性能变化规律,针对喷射打印成型硬件要求,对二者性能匹配性进行重点考察.     

Viscosity and diffusivity of a binary liquid mixture of critical composition: Study of the system 2-butoxyethanol/water

Results of measurements of the temperature dependence of the shear viscosity and the mutual diffusion coefficient of a 2-butoxyethanol/water mixture of critical composition are reported. The shear viscosities are measured with a capillary viscometer, and the diffusion coefficients by dynamic light scattering. The viscosity data are used to determine the regular (background) and the singular (critical) part of the viscosity and to analyze the crossover regime.Q ₀ has a value ofQ _o = (1.54 ± 0.60) × 10⁶ cm^–1, which is small for a binary mixture of components of small molar mass. The viscosity is dominated by singular contributions in a narrow temperature range (T _c – T) 1.2 K. The singular contributions can be neglected for temperatures (T_c–T) 11 K. The function =_b expz H, given in the literature, represents the viscosity data in the temperature range 3 mK (T _c – T) 25 K using the asymptotic form of the functionH for (q _d/q _c) 0 (q _d,q _c, parameter of the theory). This limit corresponds to the case in which the background diffusion coefficient Lib can be neglected. The reduced diffusion coefficient D^* calculated from the light-scattering data as a function of the scaling variable x(=q) is represented by the approximation of the dynamic scaling function proposed in the literature.     

Extraction of gold(III) from hydrochloric acid solutions by CTAB/n-heptane/iso-amyl alcohol/Na2SO3 microemulsion

The extraction of Au(III) from hydrochloric acid solutions by microemulsion was studied. The extraction experiments were carried out using cetyltrimethylammonium bromide (CTAB) as surfactant and iso-amyl alcohol as co-surfactant. Au(III) was found to be extracted into the microemulsion phase due to ion pair formation such as AuCl(4)(-)CTAB(+). The influence of temperature on the extraction of Au(III) has been investigated at temperatures ranging from 288 to 313 K. Temperature was found to decrease the distribution of Au(III). Thermodynamic parameters like enthalpy and entropy of the extraction, calculated by applying Van't Hoff equation, were -36.76 kJ mol(-1) and -84.87 J mol(-1) K(-1), respectively. Furthermore, the influence of the concentrations of hydrogen ion and chloride anion on the extraction efficiency (E%) were verified. Au(III) was extracted quantitatively (E%>99%) and selectively at the whole range of HCl concentrations (0.2-5 M). Recovery of gold from electrical waste and treatment of CTAB wastewater generated from the extraction were also discussed. Thus, the extraction of Au(III) from hydrochloric acid solutions by microemulsion is an effective approach.     

Evaluation and optimization of chromium removal from tannery effluent by microemulsion in the Morris extractor

A multidisciplinary Road Accident Analysis Group with the objective of conducting in-depth investigations of specific types of accidents has existed in Denmark for some years. The group has analysed head-on collisions, left-turn accidents, truck accidents and single vehicle accidents. The data collection included police reports, the group's investigation of accident sites and vehicles involved, and interviews with the involved road users and witnesses. The main accident factors in the head-on collisions and in the single vehicle accidents were excessive speed, drunk driving and driving under the influence of illegal drugs. The primary accident factors in left-turn accidents were attention errors or misjudging the amount of time available to complete the left turn. In the truck accidents insufficient searching for visual information as well as speeding were major factors. For all the accident themes the primary injury factor was failure to wear seat- belts. The multidisciplinary approach has provided a rather precise knowledge of the contributing factors leading up to the accident. The method requires a lot of resources, which is a limiting factor for the number of accidents to be analysed in this way. However, the method is suitable for analysis of common occurring or very serious types of accidents.     

微乳体系相行为研究及铂纳米微粒的制备

对十六烷基三甲基溴化铵 (CTAB) -正辛醇 -环己烷 -H2 O微乳体系相行为进行了研究。采用分光光度计测量了表观稳定的微乳体系的吸光度的变化 ;然后采用 3种CTAB与正辛醇配比的微乳体系在 30℃下制备出了Pt纳米微粒 ,还原剂为水合肼。经透射电镜分析得出 :溶水量较大的微乳体系可以制备出粒径较小 (d =3nm)且分布极为均匀的铂纳米微粒     

Synthesis of pH-sensitive water and oil dual-absorption material using microemulsion polymerization process

pH-sensitive water and oil dual-absorption material (WODAM) has been successfully synthesized through microemulsion polymerization. Firstly, microemulsions prepared with monomers were analyzed by pseudo-ternary phase diagram. In addition, conductivities of microemulsions were tested to identify microemulsion types. Meanwhile, the factors that affected microemulsion types were analyzed. Then WODAMs were prepared, and the chemical structure was characterized using Fourier transform infrared (FTIR) spectroscopy. Liquid absorption tests indicated that both monomer ratio and microstructure of WODAMs had influences on their water absorption rate (WAR) and oil absorption rate (OAR). In addition, pH sensitivity tests showed that WODAM absorbed much water in neutral and weak alkaline solutions, but little water in strong alkaline solutions. What’s more, liquid absorption tests in cement slurry filtrate (CSF) showed that WODAM was applied to oil well cement. This paper prepared a new self-healing agent, and is of great significance to realize self-healing cement in complex downhole condition.     

聚乙烯吡咯烷酮/聚(乙烯-乙烯醇)共混膜的制备及其油水分离性能

将聚乙烯吡咯烷酮(PVP)与聚(乙烯-乙烯醇)(EVAL)共混,采用浸没沉淀法制备了PVP/EVAL共混膜,并用于油水乳液分离过程。通过全反射红外光谱、扫描电子显微镜、拉伸试验、接触角测试等对膜的组成、结构形态、机械性能、亲水性进行了表征,并研究了PVP添加量对共混膜油水分离性能的影响。结果表明:添加PVP能较显著地改变EVAL膜的结构,且共混膜的机械强度和亲水性得到明显改善,当PVP添加量为10 wt%(PVP在铸膜液中的质量分数)时,其拉伸强度和断裂伸长率分别为纯EVAL膜的1.88倍和1.34倍。当PVP添加量为4 wt%时,油水分离稳定通量为纯EVAL膜的1.81倍,截留率为92.2%,比纯EVAL膜略高。PVP添加量为10 wt%的PVP/EVAL共混膜清洗后通量恢复率由纯EVAL膜的51%增至77.98%。     

提高AEO9/醇/烷/水体系反相微乳液陶瓷墨水浓度的研究

鉴于陶瓷墨水在某些性能上存在不足,例如相对连续式喷墨打印机打印成型要求而言粘度较大、电导率偏低、固相含量不够高等问题,通过加入醇和Na2CO3等添加剂以及利用双连续结构分别对粘度、电导率等性能加以调整及提高陶瓷墨水的浓度.少量醇的加入(1%～2%)使陶瓷墨水体系粘度降低到11mPa.s左右.根据相图从双连续结构角度出发设计了陶瓷墨水的组成,考察了溶水量的变化,并借以提高陶瓷墨水固相含量,使其达到2.54%.由于双连续结构陶瓷墨水的理化性能(粘度、电导率等)仍不能完全满足要求,加入少量Na2CO3进行改性,改性后的陶瓷墨水粘度降至18mPa.s以下,电导率接近100 mS/m,稳定性良好,墨水中陶瓷颗粒粒度在10nm以下,但透光率略有降低,显微结构观察表明具有明显的双连续结构特征.     

Development of a MINLP model for the optimization of a large industrial water system

This paper presents the design of a large water system within the production and packaging areas of a brewery. In order to accomplish the task, mathematical models were developed based on a Mixed Integer Nonlinear Programming (MINLP) formulation from the open literature. These models enable the investigation of several integration options: a) direct water re-use between batch and semi-continuous consumers operating within the same time interval and b) regeneration re-use options, by designing and scheduling an on-site wastewater treatment system. A multilevel strategy was applied for this large-scale industrial problem, which firstly decomposes design problem into several smaller integration problems concerning water consumers within each section of the brewery. At the following level, water re-use and regeneration re-use opportunities between the brewhouse and the packaging areas were explored for each working day. Finally, the design of an integrated water system was performed over the entire working week by fixing identified intra-daily matches between sections. An optimum water integration scheme is proposed based on the results obtained.     

Measurement of microemulsion zone and preparation of monodispersed cerium oxide nanoparticles by W/O microemulsion method

In the W/O microemulsion system of cetyltrim ethylamine bromide (CTAB) + butanol / cyclohexane / water solution, the microemulsion area was measured and cerium oxide nanoparticles were prepared according to the principle by two-phase liquid–liquid method. The samples were analyzed by means of transmission electron microscope, X-ray diffraction, thermogravimetric-differential scanning calorimetry, and infrared. And their morphology, phase, components were investigated. The results made clear that nanometer cerium oxide could be prepared in the measured area of microemulsion and it is an effective way to gain the well dispersed and uniformly distributed nanometer cerium oxide grains with the size of about 3 nm.     

微乳液组分对体系增溶水量的影响及纳米羟基磷灰石的制备

应用电导率法研究了TritonX-100/正戊醇／环己烷体系中各组分及条件对微乳液最大增溶水量的影响。结果表明：当表面活性剂TritonX-100用量为3ml，助表面活性剂选正戊醇用量为1ml，环己烷为油相，温度为48℃，Ca（NO3）2溶液与（NH4）2HPO4溶液分别为0．24和0．14mol／L时，体系增溶水量最大，可得到较高产率的纳米羟基磷灰石。并且用XRD和TEM手段对产物进行了表征。     

大型数据中心低负荷条件下冷冻水系统研究及优化

冷冻水系统和冷热气流隔离技术已成为大型数据中心广泛使用的空调制冷方案。对机房空调运行过程分析,发现在低负荷下机房空调出水温度可能会升高,超过冷水机组回水温度设定值。本文详细分析了问题产生的原因,并根据冷冻水系统特点,提出4种解决方案并分析对比优缺点,从而为系统运维、自控系统设计和设备采购提供参考。