Factors influencing behavioural intention to patronise restaurants using iPad as a menu card

Recently, several restaurants have launched mobile technology-based self-services by replacing their printed menus with iPads. To assess the perceived value of the iPad menu from the customers’ perspective, this study proposed and tested a new research model which includes both functional and emotional aspects of customers’ attitudes. The aim was based on the supposition that an overall value judgement in regard to using the iPad menu to promote dining experience will influence customers’ behavioural intention to patronise restaurants that use the new technology; 332 usable data gathered from cyberspace were tested against the research model. The results demonstrated the importance of perceived value. All functional factors (i.e. perceived control, perceived usefulness and perceived ease of use) and emotional factors (i.e. perceived enjoyment and perceived novelty) were significantly affecting perceived value. For managers interested in investing in these mobile self-service technologies, the findings provided them with sound advice based on empirical research.     

Examining the role of perceived value in virtual communities continuance: its antecedents and the influence of experience

Although perceived value has long been recognised as an influential means of affecting continuance intention in information systems (IS), little attention has been devoted to explore its antecedents, which constitutes an important research issue. This study, building on prior literature on continued usage in IS as well as the resource-based view, proposed a model to address this gap. Our model suggests that perceived value, a major driving force for members’ satisfaction and continuance intention, is affected by four kinds of resources embedded in virtual communities, which are relationship resources, technology infrastructure, knowledge resources and human resources. To provide additional insights on the pivotal role of perceived value, we also postulate that experience moderates the link between perceived value and its antecedents. Data collected from 235 members of a professional virtual community provide strong support for the research model. It was found that perceived value exerts a great effect on both satisfaction and continuance intention. In addition, when different levels of experience are taken into consideration, relationship resources, knowledge resources and human resources were found to be more salient to high-experience members, whereas technology infrastructure was found to be more salient to low-experience members. Finally, this study discusses the implications of these findings and offers direction for future research.     

Kinetic investigation of the chlorine reduction reaction on electrochemically oxidised ruthenium

The rate and mechanism of the electroreduction of chlorine on electrooxidised ruthenium has been investigated with focus on the effect of solution pH. Current/potential curves for the reduction process in solutions with constant chloride concentration of 1.0 mol dm⁻³ and varying H⁺ concentration have been obtained with the use of the rotating disk electrode technique (RDE). It was found that the chlorine reduction rate is highly inhibited in solutions with high H⁺ concentrations and that it can be satisfactorily described by the Erenburg mechanism, previously suggested for the chlorine evolution on RuO₂ and RTO. The expression of the kinetic current as a function of chlorine and H⁺ concentration was obtained by solving the elementary rate equations of the kinetic mechanism. The kinetic constants obtained from the correlation of the kinetic current expression to the experimental data were used to simulate the dependence of the surface coverages and elementary reaction rates on overpotential.     

Chemical analysis of ozonized theobroma fat

Ozonized theobroma fat is used as raw material in the manufacture of pessaries and cosmetic creams. Ozonization of theobroma fat with water was carried out at different applied ozone dosages, and the resultant PV, acid value, iodine value, total hydroperoxide content, and FA content were determined. PV and total hydroperoxide content showed a notable increase with applied ozone dosage up to 35.7 mg/g. Acid value varied slightly from 4.1 to 9.9 mg KOH/g, and the iodine value fell to zero. PV and total hydroperoxide content increased slightly with a higher applied ozone dosage. The comparison of total hydroperoxide measurement using ferrous oxidation in xylenol orange assay and traditional iodometric assay for PV determination showed a significant linear correlation. Small amounts of oleic acid were found in ozonized theobroma fat samples with iodine value equaling zero, which demonstrated that iodine value determination is an inexact assay. During ozonization of theobroma fat, an increase in acid value of 18.9-fold with respect to the initial value was observed owing to decomposition of peroxide.     

1995年中国化学工业

介绍了１９９５年及“八五”期间中国化学工业在生产的增长、基建与技改、科技进步、对外开放、深化企业改革和强化管理方面取得的成绩；同时指出了存在问题和“九五”时期的建设目标。     

过氧化氢处理河流着生刚毛藻的效果研究

以深圳市某河流为研究对象,分析了投加H2O2对刚毛藻生物量的控制效果及其对水体p H、溶解氧、氨氮和总磷的影响。结果表明:H2O2≥1.25 mol/L时能有效抑制刚毛藻生长,使藻类光合活性在10 min内从5.8降低到0,叶绿素浓度在30 min内从5.8 mg/L降低至0.2 mg/L。现场试验投加H2O2处理河流水体中刚毛藻14 d内,藻类生物量、光合活性和叶绿素浓度降幅均高于90%。加药1 h后,河流p H值由原来的9.21~9.74迅速降低至8.23~8.80,14 d内保持在9以下。河流溶解氧、氨氮、总磷和H2O2残留浓度在除藻过程中存在变化,但是1 d后会迅速恢复至加药前水平。投加H2O2是一种有效、无污染的应急去除河流着生刚毛藻的方法。     

Mechanistic investigation of hydrogen-enhanced anodic dissolution of X-70 pipe steel and its implication on near-neutral pH SCC of pipelines

The effects of hydrogen-charging on anodic dissolution of pipe steel under near-neutral pH condition were studied by electrochemical techniques. Hydrogen-charging enhances the anodic dissolution rate of the steel. The hydrogen-enhanced dissolution increases with increasing charging current density. The hydrogen effect is attributed to the alteration of chemical potential and exchange current density of steel. Hydrogen-charging affects the corrosion process of the steel. In particular, at a high charging current density, a layer of corrosion product forms on the electrode surface to change corrosion potential and interfacial double-charge layer capacitance as well as charge-transfer resistance. The hydrogen effect factor for enhanced anodic dissolution of steel at an anodic potential of −0.4 V (SCE) is 1.53 only. Hydrogen-enhanced anodic dissolution of steel by itself may not be the major factor contributing to the high rate of crack growth in pipe steel in near-neutral pH electrolyte. A further investigation of the synergistic effect of hydrogen and stress on dissolution at the crack-tip is essential to determine the mechanism of near-neutral pH stress corrosion cracking of pipelines.     

Effect of natural antioxidants in virgin olive oil on oxidative stability of refined,bleached, and deodorized olive oil

The factors influencing the oxidative stability of different commercial olive oils were evaluated. Comparisons were made of (i) the oxidative stability of commercial olive oils with that of a refined, bleached, and deodorized (RBD) olive oil, and (ii) the antioxidant activity of a mixture of phenolic compounds extracted from virgin olive oil with that of pure compounds andα-tocopherol added to RBD olive oil. The progress of oxidation at 60°C was followed by measuring both the formation (peroxide value, PV) and the decomposition (hexanal and volatiles) of hydroperoxides. The trends in antioxidant activity were different according to whether PV or hexanal were measured. Although the virgin olive oils contained higher levels of phenolic compounds than did the refined and RBD oils, their oxidative stability was significantly decreased by their high initial PV. Phenolic compounds extracted from virgin olive oils increased the oxidative stability of RBD olive oil. On the basis of PV, the phenol extract had the best antioxidant activity at 50 ppm, as gallic acid equivalents, but on the basis of hexanal formation, better antioxidant activity was observed at 100 and 200 ppm.α-Tocopherol behaved as a prooxidant at high concentrations (>250 ppm) on the basis of PV, but was more effective than the other antioxidants in inhibiting hexanal formation in RBD olive oil.o-Diphenols (caffeic acid) and, to a lesser extent, substitutedo-diphenols (ferulic and vanillic acids), showed better antioxidant activity than monophenols (p- ando-coumaric), based on both PV and hexanal formation. This study emphasizes the need to measure at least two oxidation parameters to better evaluate antioxidants and the oxidative stability of olive oils. The antioxidant effectiveness of phenolic compounds in virgin olive oils can be significantly diminished in oils if their initial PV are too high.     

超支化聚酯的合成及光固化性能研究

通过甲基四氢苯酐和环氧丙醇的开环聚合反应，一步法制备超支化聚酯，聚酯的数均摩尔质量为1450～2600g／mol，支化度在0．41～0．71之间。用甲基丙烯酸缩水甘油酯改性，合成了UV固化超支化聚酯，并对其光固化性能进行了初步研究，发现超支化聚酯能有效降低固化膜的线收缩率，聚酯的官能度越高，固化膜的硬度越大，固化速度越快，在约1s的固化时问内凝胶率超过75％。     

Markov随机场与Gaussian曲线在MR图像分割中的应用

针对扫描的人脑组织MR图像边缘分辨率低、模糊性大的特点,本文提出了一种基于模糊Markov随机场和Gaussian曲线相结合的MR图像最佳阈值分割方法。该方法通过对图像的像素邻域属性的统计将模糊论引入其中,建立模糊Markov随机场,并利用Gaussian曲线对二维直方图最佳一维投影进行拟合,确定出图像中各脑组织的二维阈值点,在二维直方图上实现对脑组织的分割。通过实验表明,本算法能够有效提高脑组织的分辨率,对噪声的鲁棒性、结果区域的连通性相对于一维Otsu和二维Otsu算法都有了很大的提高。