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51.
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53.
A fluorometric methods is described for determination of cardiac and urinary 3-methoxytyramine, a metabolite of dopamine. Methoxy metabolites were isolated on Amberlite CG-50 resin and oxidation to emitter form was performed with K3Fe(CN)6. Good specificity and sensitivity of determination, and a high recovery of 3-MT were obtained. 相似文献
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For three types of self-sucking impellers (fourand six-pipe and disk impellers) mixing power, initial point, amount of gas leaving the impeller and mass transfer coefficient were determined experimentally. Investigations were performed for two systems: water and biomass solution.From the point of view of a minimum mixing power and maximum mass transfer coefficient the best impeller has been chosen. Fuzzy multiobjective optimization for determination of optimum operating conditions is proposed.List of Symbols
c
concentration of oxygen
-
D
tank diameter
-
d
impeller diameter
-
g
acceleration of gravity
-
H
height of liquid in the tank
-
H
height of liquid above impeller, H=H-y
-
k
consistency coefficient
-
k
L
a
volumetric mass transfer coefficient
-
N
rotational speed of impeller
-
n
flow behaviour index
-
P
mixing power for pure liquid
-
P
G
mixing power for aerated liquid
-
V
G
volumetric air flow rate
-
y
distance of impeller from the tank bottom
-
v
a
apparent kinematic viscosity of liquid
-
density of liquid
-
time
-
gas hold-up
- Eu=P/N
3
d
5
or EuG=P
G
/N
3
d
5
Euler Number for non-gassed or aerated liquid
- Fr=N
2
d/g
Froude Number
- Fr*=N
2
d
2
/g(H -y)
modified Froude Number
- KG=V
G
/N d
3
gas flow number
- Re=N d
2
/v
a
Reynolds Number
- Sh=k
K
a/(g
2
/v
a
)1/3
Sherwood Number 相似文献
59.
B. Bilińska 《Histochemistry and cell biology》1989,93(1):105-110
Summary Effect of LH, vinblastine and cytochalasin B on the cytoskeleton of cultured Leydig cells was investigated using monoclonal antibodies and fluorescence microscopy. After LH addition and treatment with cytoskeletal disrupting drugs, three main effects were observed: 1) increase of androgen level secreted by cultured mouse Leydig cells, 2) changes of cell-shape towards regular and rounded, 3) increase of 5,3-HSD activity. The results are discussed in respect to possible involvement of cytoskeleton in the regulation of steroidogenesis. 相似文献
60.
I Grys M Dudziak W Piechota W Rózański M Su?ek M Adamczyk-Szymańska 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1990,45(49-50):984-986
The study involved 126 patients with cholelithiasis. Set of biochemical, radiological, endoscopic, and ultrasound examinations was carried out in these patients. Potential coincidence of clinical symptoms and causes of so-called postcholecystectomy syndrome was the purpose of a 1-year follow-up studies. The significance of the results are discussed. 相似文献