一种纳米TiO2粉体防团聚的新方法

开发了一种新的低成本防团聚方法——泡沫悬浮法。对泡沫悬浮法和共沸蒸馏法的防团聚效果进行了系统比较。结果表明，泡沫悬浮法可以有效抑制煅烧过程中纳米TiO₂晶粒的粗化和一次粒径的长大。泡沫悬浮法所得纳米TiO₂的粉体还具有团聚粒径小、粒度分布窄以及比表面积大的优点。通过FTIR、TG、DTA和松装密度实验对泡沫悬浮法的防团聚机理进行了研究，提出了纳米TiO₂防团聚模型。     

Immobilization of cellulase using polyurethane foam

Cellulase was covalently immobilized using a hydrophilic polyurethane foam (Hypol®FHP 2002). Compared to the free enzyme, immobilized cellulase showed a dramatic decrease (7.5-fold) in the Michaelis constant for carboxymethylcellulose. The immobilized enzyme also had a broader and more basic pH optimum (pH 5.5–6.0), a greater stability under heat-denaturing or liquid nitrogen-freezing conditions, and was relatively more efficient in utilizing insoluble cellulose substrates. High molecular weight compounds (Blue Dextran) could move throughout the foam matrix, indicating permeability to insoluble celluloses; activity could be further improved 2.4-fold after powdering, foams under liquid nitrogen. The improved kinetic and stability features of the immobilized cellulase combined with advantageous properties of the polyurethane foam (resistance to enzymatic degradation, plasticity of shape and size) suggest that this mechanism of cellulase immobilization has high potential for application in the industrial degradation of celluloses.     

One-step synthesis of Fe-Ni hydroxide nanosheets derived from bimetallic foam for efficient electrocatalytic oxygen evolution and overall water splitting

For the first time, the Fe-Ni LDH nanosheets were prepared through simple one-step hydrothermal treatment of Fe-Ni bimetallic foam both as the substrate and Fe/Ni sources. The ratio of Ni/Fe elements played the important role in realizing the optimal catalytic activities for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). An alkaline water electrolyzer was constructed with the Fe-Ni hydroxide nanosheets/Fe-Ni alloy foam-60% Fe as anode and Ni(OH)₂/Fe-Ni alloy foam-25% Fe as cathode, which displays superior electrolytic performance (affording 10 mA/cm² at 1.62 V) and lasting durability.     

纳米-微米复合孔泡沫陶瓷固定化脂肪酶

考察了泡沫陶瓷的孔径分布和表面性质对脂肪酶固定化的影响.研究表明,泡沫陶瓷的纳米孔孔径分布非常适合脂肪酶的固定化,对固定化酶的催化效率有决定性的影响.经1h的定化,泡沫陶瓷固定化酶的活性达商业化硅藻土固定化酶的1.33倍,体积活力为其2.63倍,蛋白载量为45.36mg/g陶瓷,比活为1215.39U/g,活力回收为41.2%.泡沫陶瓷固定化脂肪酶在有机相乙酸乙酯合成中表现优良,连续使用5次,每次反应3h,乙酸转化率均在93%左右.     

Absorption characteristics of masjid carpets

This work investigated the absorption characteristics of eight types of carpets that are especially designed and manufactured for masjids and two types of carpets pads. Measurements were carried out in the reverberation room according to ISO 354. Each type was tested three times: first when it was installed directly on the floor, second when it was installed above 5.7 mm of polyurethane foam, and last when it was installed above 10 mm of polyethylene foam. The results showed that the absorption coefficient is directly proportional to frequency and knot density. The results also demonstrated that adding pads of polyurethane or polyethylene foam increased the absorption, principally in the mid-frequency range. The effect of polyurethane foam on absorption was higher than that of polyethylene foam. Finally, the absorption coefficients of the examined carpets were found to be close to those of Muslim worshippers when they are in the position known as “standing in rows”.     

Hierarchically Structured Porous Silica Spheres by Microemulsion/Vesicle Templating for Hydrodesulfurization of Fluid Catalytic Cracking Diesel

A series of hierarchically structured porous silica sphere (HSPSS) materials are successfully fabricated by a facile, one‐step microemulsion/vesicle bimodal method in a multicomponent microemulsion system of P123/n‐butanol/1,3,5‐trimethylbenzene/KCl/H₂O (surfactant/cosurfactant/oil/salt/water). The pore structures of the obtained HSPSS products consist of mesocellular foam and mesostructured vesicles. In contrast to the traditional porous silica materials the new structures combine two separate, distinct mesophases with different‐sized mesovoids in a single porous sphere. Moreover, the proportion of every mesophase in obtained HSPSS can be easily adjusted by tuning the initially added amount of n‐butanol or KCl in this multicomponent microemulsion system. When the molar ratio of KCl/tetraethoxysilane is 2.15, the obtained HSPSS material is turned into uniform mesostructured vesicle silica spheres, which consist of many small diameter vesicle particles. The hydrodesulfurization (HDS) activity of fluid catalytic cracking diesel over the HSPSS was tested. HSPSS‐0.75‐1.43 catalyst support with multiple mesoporous structures shows the highest HDS efficiency (98.5%) among all the studied catalysts.     

Treatment of Oily Wastewater by Using Porous PVA Hydrogels as Oil Adsorbent

The adsorption of crude oil from wastewater on the crosslinked poly(vinyl alcohol) hydrogel (HPVA) and its foam (HPVAF) was reported. The macroporous HPVAF was prepared by adding CaCO₃ and epichlorohydrin as pore-forming agent and crosslinker, respectively. The prepared hydrogels were characterized, and their ability to adsorb and immobilize the crude oil was assessed by gravimetric method at the optimum condition. The HPVAF carrier demonstrated the improvement in the hydrocarbon trapping than the HPVA one. Scanning electron microscopy showed the presence of extracellular structures that could play an important role in the immobilization stability of crude oil on polymers. As well, the percentage removal ability of the crude oil by HPVAF was approximately, 82%. The results suggest the potential of using HPVA and HPVAF films as trapping for crude oil to enhance the treatment of oily wastewater with a low cost in an open marine environment.     

PHMG化学键合改性抗菌聚氨酯软质泡沫的制备及性能

通过一步法模塑发泡工艺,将聚六亚甲基胍盐酸盐(PHMG)键合到聚氨酯(PU)分子链上,制备了抗菌聚氨酯软质泡沫。通过红外光谱表征抗菌聚氨酯的化学结构,并用紫外光谱测试聚氨酯中PHMG的键合率,同时测试了聚氨酯的泡孔结构、力学性能、抗菌性能和防霉性能。结果表明,当PHMG的质量分数为0.5%时,聚氨酯中PHMG的键合率达到76.0%,对大肠杆菌和金黄色葡萄球菌的抑菌率均超过99.5%,其防霉等级为0级。     

大隐静脉高位结扎联合泡沫硬化剂注射治疗大隐静脉曲张的临床护理观察

目的对应用全面护理模式对患有大隐静脉曲张疾病的患者在接受大隐静脉高位结扎联合泡沫硬化剂注射治疗期间实施护理的临床效果进行研究。方法选择广州市番禺区中医院收治的88例患有大隐静脉曲张疾病的患者,随机分为对照组和治疗组,平均每组44例。采用传统大隐静脉剥脱术和常规护理模式对对照组患者实施治疗和护理;采用大隐静脉高位结扎联合泡沫硬化剂注射方式和全面护理模式对治疗组患者实施治疗和护理。结果治疗组患者大隐静脉曲张疾病的治疗手术治疗效果明显优于对照组;对大隐静脉曲张手术治疗期间的护理满意度明显高于对照组;住院治疗总时间明显短于对照组。结论应用全面护理模式对患有大隐静脉曲张疾病的患者在接受大隐静脉高位结扎联合泡沫硬化剂注射治疗期间实施护理的临床效果非常明显。