Micromixing enhanced synthesis of HRPIBs catalyzed by EADC/bis(2-chloroethyl)ether complex

SummaryThe formation and action of human prothrombin-activating enzyme is described. The study of the formation of the enzyme leads to the following conclusions :1. The enzyme is formed from factor V, factor X and phospholipid in the presence of calcium. If one of the reagents is omitted no activity develops.2. Factor V and factor X need activation by thrombin and for instance Russell Viper Venom, respectively.3. A linear relationship exists between the inverse of factor Va concentration and the inverse of enzyme concentration.4. A linear relationship exists between the inverse of factor Xa concentration and the inverse of enzyme concentration.5. A linear relationship exists between the inverse of phospholipid concentration and the inverse of enzyme concentration at small phospholipid concentration.6. A linear relationship exists between the phospholipid concentration and the inverse of enzyme concentration at high phospholipid concentration.The study of the action of the enzyme leads to the conclusion that human prothrombin is substrate and an inhibitor if present in excess.The observed phenomena are best explained by the hypothesis that factor Va and factor Xa adsorb onto the phospholipid surface. When both factors are adsorbed close together they are active as an enzyme. This activity depends on two active centers, probably one derived from factor Va and one from factor Xa.

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Microscopic Structure of Er-Related Optically Active Centers in Si

MRS Proceedings ◽

10.1557/proc-770-i7.1 ◽

2003 ◽

Vol 770 ◽

Author(s):

H. Przybylinska ◽

N. Q. Vinh ◽

B.A. Andreev ◽

Z. F. Krasil'nik ◽

T. Gregorkiewicz

Keyword(s):

Ground State ◽

Photoluminescence Spectrum ◽

Zeeman Effect ◽

Optically Active ◽

Single Type ◽

Active Centers ◽

Mbe Growth ◽

Spectral Components ◽

Er Doped ◽

Successful Observation

AbstractA successful observation and analysis of the Zeeman effect on the near 1.54 μm photoluminescence spectrum in Er-doped crystalline MBE-grown silicon are reported. A clearly resolved splitting of 5 major spectral components was observed in magnetic fields up to 5.5 T. Based on the analysis of the data the symmetry of the dominant optically active center was conclusively established as orthorhombic I (C2v), with g‼≈18.4 and g⊥≈0 in the ground state. The fact that g⊥≈0 explains why EPR detection of Er-related optically active centers in silicon may be difficult. Preferential generation of a single type of an optically active Er-related center in MBE growth confirmed in this study is essential for photonic applications of Si:Er.

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Competition of Self-Organized Rotating Helical Autowaves in Nonequilibrium Dissipative System with Three-Level Active Centers

Telecommunications and Radio Engineering ◽

10.1615/telecomradeng.v67.i4.80 ◽

2008 ◽

Vol 67 (4) ◽

pp. 353-377

Author(s):

D. N. Makovetskii

Keyword(s):

Dissipative System ◽

Active Centers ◽

Self Organized

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ESTIMATION OF THE SELECTIVITY OF THE ACTIVE CENTERS OF SORBENTS DURING SORPTION OF ECOTOXICANTS FROM MULTICOMPONENT SOLUTIONS

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2018-84-9-51-54 ◽

2018 ◽

Vol 84 (9) ◽

pp. 51-54

Author(s):

V. I. Vigdorovich ◽

L. E. Tsygankova ◽

O. V. Alekhina ◽

M. N. Uryadnikova

Keyword(s):

Active Centers ◽

Multicomponent Solutions

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MAGNETIC FIELD IMPACT UPON TRIBOTECHNICAL CHARACTERISTICS OF PERMANENT CONNECTIONS IN RELATION TO FRICTION SHOCK ABSORBERS

Bulletin of Bryansk state technical university ◽

10.30987/1999-8775-2020-10-4-11 ◽

2020 ◽

Vol 2020 (10) ◽

pp. 4-11

Author(s):

Victor Tikhomirov ◽

Aleksandr Gorlenko ◽

Stanislav Volohov ◽

Mikhail Izmerov

Keyword(s):

Magnetic Field ◽

Friction Factor ◽

Physical Contact ◽

Active Centers ◽

Press Fit ◽

Electro Magnetic Field ◽

Investigation Methods ◽

Electro Magnetic ◽

The Impact ◽

The Magnetic Field

The work purpose is the investigation of magnetic field impact upon properties of friction steel surfaces at fit stripping with tightness through manifested effects and their wear visually observed. On the spots of a real contact the magnetic field increases active centers, their amount and saturation with the time of dislocation outlet, and has an influence upon tribo-mating. The external electro-magnetic field promotes the increase of the number of active centers at the expense of dislocations outlet on the contact surface, and the increase of a physical contact area results in friction tie strengthening and growth of a friction factor. By the example of friction pairs of a spentonly unit in the suspension of coach cars there is given a substantiation of actuality and possibility for the creation of technical devices with the controlled factor of friction and the stability of effects achieved is also confirmed experimentally. Investigation methods: the fulfillment of laboratory physical experiments on the laboratory plant developed and patented on bush-rod samples inserted with the fit and tightness. The results of investigations and novelty: the impact of the magnetic field upon the value of a stripping force of a press fit with the guaranteed tightness is defined. Conclusion: there is a possibility to control a friction factor through the magnetic field impact upon a friction contact.

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Effect of grain size on the vapour phase hydration of monoclinic and triclinic modifications of tricalcium silicate; role of high temperature activation

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19911993 ◽

1991 ◽

Vol 56 (10) ◽

pp. 1993-2008

Author(s):

S. Hanafi ◽

G. M. S. El-Shafei ◽

B. Abd El-Hamid

Keyword(s):

Particle Size ◽

Vapour Phase ◽

Tricalcium Silicate ◽

Active Centers ◽

Thermally Activated ◽

Grain Sizes ◽

Intermediate Size ◽

Surface Active ◽

Temperature Activation

The hydration of tricalcium silicate (C3S) with three grain sizes of monoclinic (M) and triclinic (T) modifications and on their thermally activated samples were investigated by exposure to water vapour at 80°C for 60 days. The products were investigated by XRD, TG and N2 adsorption. The smaller the particle size the greater was the hydration for both dried and activated samples from (M). In the activated samples a hydrate with 2θ values of 38.4°, 44.6° and 48.6° could be identified. Hydration increased with particle size for the unactivated (T) samples but after activation the intermediate size exhibited enhanced hydration. Thermal treatment at 950°C of (T) samples increased the surface active centers on the expense of those in the bulk. Changes produced in surface texture upon activation and/or hydration are discussed.

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