1. |
|
|
2. |
|
|
3. |
- Dunuwila, Dilum D., et al.
(author)
-
Sol-gel derived titanium carboxylate thin films for optical detection of analytes
- 1994
-
In: Analytical Chemistry. - : American Chemical Society (ACS). - 0003-2700 .- 1520-6882. ; 66:17, s. 2739-2744
-
Journal article (peer-reviewed)abstract
- The feasibility of using a sol-gel derived titanium carboxylate thin film, which can be supported on glass, for the fabrication of optical test strips was investigated using a model probe/ analyte combination. The porous films, being optically transparent and baring the capability to host probe molecules, provided an excellent system to investigate the possibility of making optical test strips. A colorimetric reagent, an iron(III) porpohyrin, was chosen as the probe molecule to detect free cyanide ion concentrations in aqueous solutions. Entrapment of the porphyrin in the film was accomplished by direct dissolution of the porphyrin in the sol-gel solutions. Chemically induced structural modifications of the polymer were carried out to stabilize the encapsulated metalloporphyrin within the sol-gel derived matrix. The syntheses of this model analyte detection system and its response are presented. An optical parameter reflective of the chemical changes that occur in the system was selected as the measurement tool; its response asymptotically increased over the cyanide ion concentration range of 40-25 000 ppm.
|
|
4. |
- Hang, Chang C., et al.
(author)
-
Automatic Tuning and Adaptation for PID Controllers—A Survey
- 1992
-
In: Adaptive Systems in Control and Signal Processing 1992.
-
Conference paper (peer-reviewed)abstract
- Adaptive techniques such as gain scheduling, automatic tuning and continuous adaptation have been used in industrial single-loop controllers for about ten years. This paper gives a survey of the different adaptive techniques, the underlying process models and control designs. The paper ends with an overview of industrial adaptive single-loop controllers.
|
|
5. |
|
|
6. |
|
|
7. |
|
|
8. |
|
|
9. |
- Sahlin, C, et al.
(author)
-
Changes in contractile response and effect of a calcium antagonist, nimodipine, in isolated intracranial arteries of baboon following experimental subarachnoid hemorrhage
- 1990
-
In: Brain Research Bulletin. - 0361-9230. ; 24:3, s. 355-361
-
Journal article (peer-reviewed)abstract
- Isolated pial arteries from a previously well-characterized model of experimental subarachnoid hemorrhage (SAH) in baboon were tested for their contractile response to 5-hydroxytryptamine (5-HT), norepinephrine (NE), and prostaglandin F2 alpha (PGF2 alpha) and the effect of the calcium antagonist, nimodipine. Autologous blood was injected cisternally at three times with one-day intervals to a total amount of 11.5-29.5 ml (mean: 18.5 ml), and the animals were killed 7 days after the first injection. Untreated animals served as controls. The degree of maximum contraction (EAm) with 5-HT and NE in the control situation was for the three arteries tested in the order middle cerebral greater than anterior cerebral greater than basilar artery. Experimental SAH markedly increased EAm, by 190-370 percent above control values (depending on type of vessel) for 5-HT and 170-185 percent for NE. In addition, the sensitivity to 5-HT was significantly increased, as evidenced by a left-shift of the concentration-response curve. Previous exposure of the artery to 10(-6) M nimodipine reduced the contractile response of both amines to approximately half, the inhibition being slightly less pronounced post-SAH. When vessels were contracted beforehand with the amines or with PGF2 alpha, followed by administration of increasing amount of nimodipine (10(-9) M to 10(-6) M), a concentration-dependent relaxation was obtained by up to 60 percent of the original level. This relaxing effect was significantly less following SAH in the experiments with NE and PGF2 alpha compared to 5-HT; the contraction in the presence of 5-HT did not differ before and after experimental SAH. The experiments show that SAH markedly enhances the intrinsic activity for both 5-HT and NE. Nimodipine inhibits the contractile response less efficiently following experimental SAH. The difference in the responsiveness to 5-HT on the one hand, and to NE and PGF2 alpha on the other, could be due to differences in the blood-induced alterations of those calcium channels that are influenced by the calcium antagonist, nimodipine.
|
|
10. |
- Åström, Karl Johan, et al.
(author)
-
Automatic Tuning and Adaptation for PID Controllers : A Survey
- 1993
-
In: Control Engineering Practice. - 0967-0661. ; 1:4, s. 699-714
-
Journal article (peer-reviewed)abstract
- Adaptive techniques such as gain scheduling, automatic tuning and continuous adaptation have been used in industrial single-loop controllers for about ten years. This paper gives a survey of the different adaptive techniques, the underlying process models and control designs. An overview of industrial products is also presented, which includes a fairly detailed investigation of four different adaptive single-loop controllers.
|
|