| 1. |
|
|
| 2. |
- Dahl, Leif, et al.
(författare)
-
Catalytic behavior and characterization of (CuO)1-z(La2O3)z/2 based catalysts deposited on γ-Al2O3 and prepared in situ with 0.0≤z≤1.00 with and without addition of Pd
- 1996
-
Ingår i: Catalysis Letters. - 1572-879X .- 1011-372X. ; 37:1-2, s. 69-77
-
Tidskriftsartikel (refereegranskat)abstract
- (CuO)(1-z)(La2O3)(z/2) based catalysts with 0.0 less than or equal to z less than or equal to 1.0 supported on gamma-Al2O3 have been prepared in situ and the phases formed have been identified by XRD, SEM and TEM/EDS studies. The catalyst with z = 0.5 exhibited the best catalytic activity for oxidation of CO (T-50 = 295 and 390 degrees C with degrees of conversions of 93 and 92% at 450 degrees C under rich and lean conditions, respectively) and C3H6 (291 and 414 degrees C; 93 and 83%) and reduction of NO (405 degrees C; 60 and 0%). This catalyst contained appreciable amounts of the perovskite phase LaAl1-xCuxO3 and the enhanced catalytic properties are ascribed to the presence of this phase. Addition of Pd to this catalyst implied that the degree of conversion of NO increased and that the light-off temperatures for all involved gas species decreased. Ageing experiments revealed that LaAl1-xCuxO3 decomposed and that Cu containing Pd particles were formed during this procedure which in turn deteriorated the catalytic properties of the catalyst.
|
|
| 3. |
- Grundström, Eva, et al.
(författare)
-
Increased expression of glial cell line-derived neurotrophic factor mRNA in muscle biopsies from patients with amyotrophic lateral sclerosis
- 1999
-
Ingår i: Journal of the Neurological Sciences. - 0022-510X .- 1878-5883. ; 162:2, s. 169-173
-
Tidskriftsartikel (refereegranskat)abstract
- The expression of glial cell line-derived neurotrophic factor (GDNF) mRNA and brain-derived neurotrophic factor (BDNF) mRNA were studied in muscle biopsies from five patients with amyotrophic lateral sclerosis (ALS), six patients with other neuromuscular diseases and eight healthy control persons. All five patients with ALS had higher GDNF mRNA expressions in their biopsies than the healthy control group (almost a three fold increase). Among the other patients only one, who had a rapidly progressing toxic polyneuropathy, showed a GDNF mRNA expression above those of the controls. The BDNF mRNA expressions in the biopsies from the ALS patients were in the same range as those from the healthy controls, although the mean value of the ALS patients was higher. The only biopsy that showed a markedly higher BDNF mRNA expression was taken from one patient with progressive muscular atrophy. These results suggest that increased GDNF mRNA expression in muscle is an unspecific response to ongoing denervation and that this response is maintained in ALS, at least temporarily. If increased GDNF mRNA in muscle proves to be a constant finding in ALS the rationale for the use of GDNF as a therapeutic agent in ALS must be questioned.
|
|
| 4. |
- Gulliksen, Jan, 1965-, et al.
(författare)
-
Analysis of Information Utilization (AIU)
- 1997
-
Ingår i: International Journal of Human-Computer Interaction. - London : Taylor & Francis Group. - 1044-7318 .- 1532-7590. ; 9:3, s. 255-282
-
Tidskriftsartikel (refereegranskat)abstract
- Analysis of information utilization (AIU) is a method for describing and analyzing how information entities identified in information analysis are being used in the work situation. AIU aims at complementing existing methods for user interface design by identifying additional requirements for human-computer interaction. The method focuses on aspects, of computer-supported work, related to cognitive load, aspects of which end users often not are explicitly aware. For skilled workers in a professional work environment, the efficiency of the user interface is extremely important. We earlier stressed that important criteria for design of user interfaces deals with making the interface "obvious" to the users, by minimizing the cognitive load associated with the handling of it. AIU is performed through observation interviews in which human-computer experts interview representative users about their work situation and observe physical information-handling routines. The analysis identifies work tasks in terms of judgments and decision-making situations, requirements concerning the tasks that may have to be performed simultaneously, important features and priorities of the information, actions the user can initiate and so on. The method supports the interface designer with human-computer interaction requirements structured for a workspace-oriented design. It is integrated in user-centered development model and supports the simultaneous development of competence, organization, work activity, and information technology. This article describes the background and contents of the method and how the results of the analysis are documented and used in the design process. A number of application projects have shown that AIU makes it possible to capture aspects of human work and information processing that are important to the design of better interfaces. AIU is not a new method for system development but complements today methods for task and information analysis with more...
|
|
| 5. |
- Gulliksen, Jan, et al.
(författare)
-
Analysis of information utilization (AIU)
- 1997
-
Ingår i: INTERNATIONAL JOURNAL OF HUMAN-COMPUTER INTERACTION. - 1044-7318. ; 9:3, s. 255-282
-
Tidskriftsartikel (refereegranskat)abstract
- Analysis of information utilisation (AIU) is a method for specifying how information entities encountered in information analysis are being physically manipulated in the work situation undergoing analysis. It focuses especially on factors affecting cognitive load. The method supports the human-computer interface designer with relevant and appropriate information structured specifically for a document oriented design methodology. It gives a suitable basis for user centred interface design, without the possible limitations that improper user participation could cause, and focuses on all aspects relevant for a ”good” work environment, such as competence, organisation, work activity and information technology development.Analysis of information utilisation is performed through ”observation-interviews” in which a human-computer expert interviews a typical user about his work situation in the domain of work and observes information handling routines that the user might not be aware of. A number of development projects have shown that this method can constitute an additional step in existing methodologies for capturing aspects of the work situation that can be directly design controlling. This paper describes the method of analysis of information utilisation, and what information that has to be documented while performing the method. It suggests how the method can be incorporated into existing in-house development methodologies, and gives an example of documented analysis results from a development project within the Swedish National Tax Board.
|
|
| 6. |
- Lin, Pei-yan, et al.
(författare)
-
Catalytic purification of car exhausts over cobalt- and copper-based metal oxides promoted with platinum and rhodium
- 1995
-
Ingår i: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 6:3, s. 237-319
-
Tidskriftsartikel (refereegranskat)abstract
- 25 Alumina-and silica-supported oxide-based catalysts were prepared, with the overall metal composition La(0.45)Sr(0.15)Ce(0.35)Zr(0.05)M(1.0) (M=Co or Cu) and promoted with 0-0.5 mg Pt-Rh per gram catalyst. The catalysts were evaluated with respect to light-off temperatures and redox characteristics, using NO/CO/C3H6/O2/N2 gas mixtures to simulate car exhaust. The activities for complete oxidation of propene and carbon monoxide increased with increasing content of metal oxides and noble metals. The catalysts were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) combined with energy-dispersive spectroscopy (EDS) analysis, temperature-programmed reduction (TPR), and specific surface area measurements (BET). SEM/TEM/XRD revealed that the alumina-supported catalysts contained well dispersed oxides of the added elements, whereas the silica-supported catalysts contained significantly larger particles of the copper or cobalt oxides, The TPR peak for reduction of cobalt oxide shifted toward lower temperatures with increasing content of Pt-Rh, indicating hydrogen spill-over from the noble metals to the cobalt oxide. The catalytic activity of the Co-based oxides supported on alumina and promoted with 0.49 mg Pt-Rh per gram catalysts was comparable to the activity of a commercial three-way catalyst (TWC), containing more than 4 times as much Pt-Rh.
|
|
