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21.
An all-alkoxide route to films and nano-phase powders of the La0.5 Sr0.5 CoO3 perovskite is described. To our knowledge, this is the first purely alkoxide-based route to (La1− x Sr x )CoO3 , and it yields phase-pure and elementally homogeneous perovskite at 700°C by heating at 2°C/min. At 700°C, a cubic unit cell was obtained with a c =3.853Å, and after further heating to 1000°C, a rhombohedral cell could be indexed: a r =5.417 Å, αr =59.94°. Ninety to 130 nm thick films of La0.5 Sr0.5 CoO3 were obtained by spin coating. The gel-to-oxide conversion was studied in some detail, using thermo-gravimetric analysis, differential scanning calorimetry, powder X-ray diffraction, IR spectroscopy, and transmission electron microscope equipped with an energy-dispersive X-ray spectrometer. 相似文献
22.
Lars?Sk?ldstamEmail author Lars?Brudin Linda?Hagfors Gunnar?Johansson 《Nutrition journal》2005,4(1):15
Objectives
Several investigators have reported that clinical improvements of patients with rheumatoid arthritis (RA), from participating in therapeutic diet intervention studies, have been accompanied by loss of body weight. This has raised the question whether weight reduction per se can improve RA. In order to test this hypothesis, three previously conducted diet intervention studies, comprising 95 patients with RA, were pooled. Together with Age, Gender, and Disease Duration, change during the test period in body weight, characterised dichotomously as reduction or no reduction (dichoΔBody Weight), as well as Diet (dichotomously as ordinary diet or test diet), were the independent variables. Dependent variables were the difference (Δ) from baseline to conclusion of the study in five different disease outcome measures. ΔESR and ΔPain Score were both characterised numerically and dichotomously (improvement or no improvement). ΔAcute Phase Response, ΔPhysical Function, and ΔTender Joint Count were characterised dichotomously only. Multiple logistic regression was used to analyse associations between the independent and the disease outcome variables. 相似文献23.
Cristhian Carrasco Carlos Solano José Mauricio Peñarrieta Henrique Macedo Baudel Mats Galbe Gunnar Lidén 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(12):1723-1725
A pentose‐rich hydrolysate fraction obtained by extraction of steam‐pretreated sugarcane bagasse was analysed with regard to dissolved phenolics. The liquid obtained after steam pretreatment (2% SO2 (w/w) at 190 °C for 5 min) was divided into two parts: one containing dissolved compounds originating from hemicellulose (with xylose as the dominating compound), and the other containing predominantly dissolved compounds originating from lignin. Using nuclear magnetic resonance, the main dissolved compounds originating from lignin were identified as the glycosylated aromatics, 5‐O‐(trans‐feruloyl)‐L‐Arabinofuranose and 5‐O‐(trans‐coumaroyl)‐L‐Arabinofuranose, together with p‐coumaric acid and small amounts of more common free phenolics such as p‐hydroxybenzaldehyde, p‐hydroxybenzoic acid and vanillin. The phenolic compounds were analysed and quantified using reversed‐phase high‐performance liquid chromatography. The findings show that SO2 steam explosion opened up new degradation pathways during lignin degradation. Copyright © 2012 Society of Chemical Industry 相似文献
24.
Christian Veauthier Gunnar Gaede Helena Radbruch Klaus-Dieter Wernecke Friedemann Paul 《International journal of molecular sciences》2015,16(7):16514-16528
Quality of Life (QoL) is decreased in multiple sclerosis (MS), but studies about the impact of sleep disorders (SD) on health-related quality of Life (HRQoL) are lacking. From our original cohort, a cross-sectional polysomnographic (PSG) study in consecutive MS patients, we retrospectively analysed the previously unpublished data of the Nottingham Health Profile (NHP). Those MS patients suffering from sleep disorders (n = 49) showed significantly lower HRQoL compared to MS patients without sleep disorders (n = 17). Subsequently, we classified the patients into four subgroups: insomnia (n = 17), restless-legs syndrome, periodic limb movement disorder and SD due to leg pain (n = 24), obstructive sleep apnea (n = 8) and patients without sleep disorder (n = 17). OSA and insomnia patients showed significantly higher NHP values and decreased HRQoL not only for the sleep subscale but also for the “energy” and “emotional” area of the NHP. In addition, OSA patients also showed increased NHP values in the “physical abilities” area. Interestingly, we did not find a correlation between the objective PSG parameters and the subjective sleep items of the NHP. However, this study demonstrates that sleep disorders can reduce HRQoL in MS patients and should be considered as an important confounder in all studies investigating HRQoL in MS. 相似文献
25.
Björn Schulz Tobias Meinert David Bierbüsse Michel Busen Nina Körtzinger Michael Stankowski Gunnar Seide 《化学,工程师,技术》2016,88(10):1501-1507
Aerogels are high‐performance materials used for space and aviation purposes. Cellulose aerogel fibers have been investigated under real space conditions for their insulation properties. The experiments were carried out in a one‐stage high‐altitude research rocket of the improved ORION type. A cuboid module with measurement cells, camera modules, and electronic devices has been developed for monitoring the insulation behavior of cellulose aerogel non‐woven samples. The thermal behavior of these samples has been analyzed and compared to cellulose cloth (cotton) and aluminum for reference. 相似文献
26.
非织造布在世界范围内广泛生产.全球标准是非织造布生产的一个竞争因素.目前,非织造布在市场中的优势不仅是价格便宜,而且质量优良.因此,为了保持非织造布的市场,有必要提高非织造布质量.在线检测系统可检测破洞、薄区、厚区等疵点,但影响非织造布质量的不仅仅是疵点,还取决于其光学均匀性.尤其对于面密度较小(如15 g/m2)的非织造布,明显的不规则纤维分布会影响顾客的主观评价.阐述了一种代表主观评价的客观图像分析方法. 相似文献
27.
28.
Lars Berggren Jesper Ederth Gunnar A. Niklasson 《Solar Energy Materials & Solar Cells》2004,84(1-4):329
Tungsten oxide is a widely used electrochromic material for smart windows. In order to study the charge carriers involved in the electrochromic process, it is important to characterize the electrical transport in tungsten oxide. Substoichiometric amorphous tungsten oxide films were prepared by DC-magnetron sputtering. The films were electrochemically intercalated with lithium. The Li/W intercalation ratios for the tungsten oxide films were in the range 0.15–0.53. Temperature dependent resistivity measurements were performed in the temperature range 77–300 K for samples at different lithium intercalation levels. It was found that the data are consistent with the variable range hopping model. 相似文献
29.
A power plant based on chemical-looping combustion offers both a possibility of high net power efficiency and separation of the greenhouse gas CO2. This is due to the way the oxidation of the fuel takes place. Instead of oxidizing the fuel with oxygen from the combustion air, the fuel is oxidized by an oxygen carrier, i.e., an oxygen-containing compound. The oxygen carriers that have been suggested in previous studies are metal oxides like NiO, Fe2O3 and Mn3O4. The reduced oxygen carrier is in the next step reoxidized by air in a second reactor and then recirculated to the first reactor. In this way, fuel and air are never mixed and the fuel oxidation products CO2 and water leave the system undiluted by air. All that is needed to get an almost pure CO2 product is to condense the water vapour and remove the liquid water.Chemical-looping combustion (CLC) is also claimed to reduce the fuel exergy destruction in the overall reaction of combustion of the fuel. This gives a possibility to increase the net power efficiency.This paper gives an introduction to chemical-looping combustion. Results from simulations and a detailed exergy analysis of two different CLC gas turbine (GT) systems are also presented. The first system utilizes methane as a fuel and NiO as oxygen carrier. The second system utilizes a fuel gas mixture consisting mainly of CO and H2, simulating a fuel gas from for instance coal gasification. Results for this system are given for simulations with both NiO and Fe2O3 as oxygen carrier. The two systems are compared to comparable simulated systems with conventional combustion of the same fuel. The exergy analysis shows that the irreversibilities generated upon combustion of the fuel are reduced. The net power efficiency of the CLC–GT systems is similar or higher than for the corresponding GT systems with conventional combustion. The net power efficiency of CLC systems could be even further increased if the exergy remaining in the exhaust could be utilized in an efficient way. 相似文献
30.
In an ageing society, families may have an important role in the caretaking and well-being of the elderly. Demographic changes have an impact on the size and structure of families; one aspect is how intergenerational support is distributed when there is a need for support to both older and younger generations at the same time. Another vital aspect of the provision of care for the elderly is geographic proximity. This study is oriented towards the potential “both-end carers” i.e. persons who have grandchildren in potential need of care while still having living ageing parents. The incidence of having grandchildren and having living parents at age 55 and the proximity between generations is described using Swedish register data. The results show that the share of 55-year-olds who are grandparents decreased dramatically from 70% to 35% between 1990 and 2005. As expected, more 55-year-olds have living parents—a proportion that increased from 37% to 47% during this period. As a result of delayed childbearing among the children of these cohorts, the likelihood of belonging to a four-generation family among 55-year-olds has not increased, despite increased longevity. Furthermore, most individuals live within daily reach of their kin and no evidence was found of a trend of increasing geographic distances between generations. 相似文献