CO Oxidation over Au/TiO2–Carbon Catalysts: The Effect of Thermal Treatment, Stability and TiO2 Support Structure

The effect of thermal treatment on the catalyst structure and the CO oxidation performance of a Au/TiO₂ catalyst supported on a carbon composite material has been studied. X-ray absorption spectroscopy shows that the carbon composite stabilises the TiO₂ and prevent agglomeration of the particles. The activity measurements show that both Au and TiO₂ need to be present in order to obtain catalytic activity. The catalytic performance was found to be strongly affected by thermal treatments of the active phase prior to the reaction. The thermal treatments have an effect on the ordering of the TiO₂ structure, and on the CO oxidation activity. Heat treatment after Au deposition has a positive effect on the CO oxidation performance. This is attributed to the introduction of a stronger interaction between the oxide and Au which improves the catalytic activity. This also indicates that the TiO₂ support and the Au–TiO₂ interface play important roles in the CO oxidation reaction.     

The Potential Role of Lycopene for the Prevention and Therapy of Prostate Cancer: From Molecular Mechanisms to Clinical Evidence

Lycopene is a phytochemical that belongs to a group of pigments known as carotenoids. It is red, lipophilic and naturally occurring in many fruits and vegetables, with tomatoes and tomato-based products containing the highest concentrations of bioavailable lycopene. Several epidemiological studies have linked increased lycopene consumption with decreased prostate cancer risk. These findings are supported by in vitro and in vivo experiments showing that lycopene not only enhances the antioxidant response of prostate cells, but that it is even able to inhibit proliferation, induce apoptosis and decrease the metastatic capacity of prostate cancer cells. However, there is still no clearly proven clinical evidence supporting the use of lycopene in the prevention or treatment of prostate cancer, due to the only limited number of published randomized clinical trials and the varying quality of existing studies. The scope of this article is to discuss the potential impact of lycopene on prostate cancer by giving an overview about its molecular mechanisms and clinical effects.     

Studies of the Photodegradation of Spruce Lignin by Nmr Spectroscopy

The light-induced degradation of lignin was studied using spruce MWL impregnated on handsheets prepared from cotton linters. The sheets were irradiated with simulated sunlight and the lignin was extracted. Solutions of untreated and irradiated lignin were studied by ¹H and ¹³C NMR spectroscopy. The results showed that α- and β- ether and α-β bond cleavage were the main reactions. The main degradation products were vanillin and vanillic acid. The amount of terminal groups containing aromatic aldehyde and carboxyl groups also incre- ased on irradiation. The existing α- C=O groups were transformed mainly to carboxyl groups. However, the results indicate that new α- C=O groups were generated on irradiation. The methoxyl content decreased and some degradation of aromatic rings took place. However, no formation of quinoid structures was observed. Degradation of phenylcoumaran units was evident, α- Ether cleavage in phenylcoumarans could possibly lead to formation of stilbenes and stilbene derived chromophores.     

重载AGV在铁路检修行业的应用

本文通过重载AGV这一自动化高科技产品在铁路检修行业的应用,介绍了重载AGV的结构特点及工作流程。重载AGV的应用能够极大地节省人力、提高生产效率、降低劳力成本和劳动强度,促进铁路装备现代化进程的发展。     

关于密码协议攻击的研究

该文通过具体实例从不同的角度讨论了对密码协议的各种攻击,并阐述了这些攻击产生的原因及防止它们的一般方法。     

Language deficits, localization, and grammar: Evidence for a distributive model of language breakdown in aphasic patients and neurologically intact individuals.

Selective deficits in aphasic patients' grammatical production and comprehension are often cited as evidence that syntactic processing is modular and localizable in discrete areas of the brain (e.g., Y. Grodzinsky, 2000). The authors review a large body of experimental evidence suggesting that morphosyntactic deficits can be observed in a number of aphasic and neurologically intact populations. They present new data showing that receptive agrammatism is found not only over a range of aphasic groups, but is also observed in neurologically intact individuals processing under stressful conditions. The authors suggest that these data are most compatible with a domain-general account of language, one that emphasizes the interaction of linguistic distributions with the properties of an associative processor working under normal or suboptimal conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychophysiological, somatic, and affective changes across the menstrual cycle in women with panic disorder.

This study explored menstrual symptoms, somatic focus, negative affect, and psychophysiological responding across the menstrual cycle in women with panic disorder and controls. Women with and without panic disorder completed a psychophysiological task and self-report measures of menstrual symptoms, somatic focus, and negative affect on 4 occasions across 2 menstrual cycles (twice during intermenstrual and premenstrual phases). Women in the panic disorder group exhibited greater skin conductance magnitude and more frequent skin conductance responses to anxiety-provoking stimuli during the premenstrual phase than did controls. Compared to controls, women with panic disorder endorsed more severe menstrual symptoms relating to bodily sensations, anxiety sensitivity, state and trait anxiety, fear of body sensations, and illness-related concerns. The applicability of anxiety sensitivity to understanding the relation of menstrual reactivity and panic disorder is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Carbon based conductive photoresist

A conductive photoresist for photolithographic application was studied here. The negative near-UV sensitive epoxy-based photoresist was used as a polymer matrix and conductive carbon black was used as functional filler. DC electrical resistivity of composite as a function of filler concentration has a well-known S-shape. After UV-exposure the resistivity of the composite decreases for almost five orders of magnitude, mostly at percolation threshold (approx. 0.6 vol.%). This effect can be attributed to the fully cross-linked polymer structure formed during UV-exposure of the composite. The resistivity of prepared samples also depend on the state of dispersion of the functional filler obtained using different dispersing additives. Composites with better dispersed particles have lower resistivities. This effect remained below one order of magnitude and decreased after UV-exposure. The composites with carbon black concentration of up to 1.1 vol.% are suitable for spin-coating and photolithography.     

The effect of coating crystallization and substrate impurities on magnetron sputtered doped LaCrO3 coatings for metallic solid oxide fuel cell interconnects

For IT-SOFC metallic interconnects, surface coating is effective for reducing Cr poisoning of the cathode and controlling scale growth. In this work, LaCrO₃ and doped LaCrO₃ coatings were deposited by magnetron sputtering on SS446 and Crofer 22 APU substrates. The crystallization process was studied by means of X-ray Diffraction (XRD) during the annealing of the sputter coated samples in ambient and reducing environments. The formation of intermediate phases when annealed in air, LaCrO₄ and La₂CrO₆, results in vacancy formation upon subsequent transformation to the LaCrO₃ phase and thus a decreased oxidation resistance. While the avoidance of an intermediate phase change when the coatings are initially annealed in a reducing environment leads to dense and compact coatings. This confirmed both by XRD and by scanning electron microscopy (SEM) of coating cross-sections. Crofer 22 APU alloys with various silicon and aluminum levels are deposited with doped LaCrO₃ coating to study substrate impurity effects on coating properties. It was found that silicon content in the substrates leads to increased ASR of the coatings. In addition, long term annealing in air shows that aluminum impurities in the substrate can lead to the formation of alumina at substrate grain boundaries, which in turn leads to enhanced Mn migration at the grain boundaries. Increased manganese concentrations at the film/grain boundary interface in coated samples produces larger than normal amounts of (Mn,Cr)₃O₄ spinel in these regions, which cracks the coating and reduces the ASR value due to extra electronic conduction path. A similar mechanism is not observed in a low Al/Si alloy.     

Pursuit and adjustment of goals during unemployment: The role of age.

This longitudinal study investigated the predictive value of 2 self-regulatory processes (goal pursuit and goal adjustment) on mental health and reemployment success over a period of 8 months. A total of 87 unemployed job seekers participated in this study. There is some evidence that age moderated the relationship between goal pursuit and goal adjustment with mental health and reemployment success. Contrary to expectations, goal pursuit was positively related to mental health for relatively older individuals. The authors found no effects of goal adjustment on mental health. However, as expected, goal adjustment had a negative relationship with reemployment success for relatively younger individuals. The authors found no moderator effects of age on the relationship between goal pursuit and reemployment success. Thus, the study revealed different relationships between self-regulatory processes and mental health as well as reemployment success for younger and older individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)