• Journal of Environmental Health Sciences
• /
• v.34 no.3
• /
• pp.233-239
• /
• 2008

In order to improve reactor performance of existing sewage treatment plants, the feasibility of enhancing reactor performance by bioaugmentation using EM as bioaugmentation agent and the effects of anoxic: oxic time ratio on reactor performance were investigated. Continuous and intermittent aeration modes were compared under the 6 hr of HRT. Three different types of intermittent aeration modes, that is, 15 min, of anoxic:45 min of oxic, 30 min of anoxic: 30 min of oxic, and 45 min of anoxic: 15 min oxic respectively were chosen as test modes to study the effects of anoxic : oxic time ratios on reactor performance. The optimum anoxic: oxic time ratio was 30 min:30 min when considering simultaneous removal of organic, nitrogen and phosphorus. When applying EM into a continuously aerated reactor under the varying dosing rates of 50-200 ppm, reactor performance in terms of organic and nitrogen removal efficiencies was not improved at all. Nitrogen removal efficiency was increase when the EM dosing rate was increased. However the degree of improvement was slight when the EM was injected above 100 ppm. However optimum phosphorus removal was found at the EM dosing of 200 ppm. Thus it was found that optimum injection concentration of EM is 200 ppm. It is apparent that putting EM into a sewage treatment plant significantly affects the T-N removal efficiency of the reactor by enhancing denitrification efficiency especially in operational conditions of relatively long anoxic periods. To achieve reciprocal condition in a reactor with intermittent aeration it is necessary to enhance the reactor performance by EM injection. In the case of modifying existing continuously aerated reactors into intermittent aerated reactors, it is obvious that operating costs of aeration would be reduced by reducing aeration time when compared with existing conventional sewage treatment plants.

• Membrane and Water Treatment
• /
• v.10 no.2
• /
• pp.179-189
• /
• 2019

This study aimed to investigate the effect of temperature and solid retention time (SRT) on membrane fouling in a membrane bioreactors (MBRs). For this purpose, a lab-scale submerged MBR system was used. This system operated at two SRTs of 15 and 5 days, three various temperatures (20, 25 and $30^{\circ}C$) and hydraulic retention time (HRT) of 8 h. The results indicated that decreased the cake layer resistance and increased particles size of foulant due to increasing temperature and SRT. Fourier transform infrared (FTIR) analysis show that the cake layer formed on the membrane surface, contained high levels of proteins and especially polysaccharides in extracellular polymeric substances (EPS) but absorbance intensity of EPS functional groups decreased with temperature and SRT. EEM analysis showed that the peak on the range of Ex/Em=220-240/350-400 in SRT of 15 and temperature of $30^{\circ}C$ indicates the presence of fulvic acid in the cake. In addition, as the temperature rise from 20 to $30^{\circ}C$, concentration of soluble microbial products (SMP) increased and COD removal reached 89%. Furthermore, the rate of membrane fouling was found to increase with decreasing temperature and SRT.

• Electrical & Electronic Materials
• /
• v.10 no.3
• /
• pp.226-232
• /
• 1997

Ternary semiconductor $Al_{x}$G $a_{1-x}$ Sb crystals which have energy gap of 0.7eV-1.6 eV at room temperature according to the composition ratios were grown by the vertical Bridgman method. The characteristics of the crystals were investigated by XRD, HRTEM and Hall effect. The lattice constants of $Al_{x}$G $a_{1-x}$ Sb crystals were varied from 6.096A over .deg. to 6.135A over .deg. with the composition ratio x. The Hall effect of the $Al_{x}$G $a_{1-x}$ Sb crystals were measured by van der Pauw method with the magnetic field of 3 kilogauss at room temperature. The resistivities of Te-doped $Al_{x}$G $a_{1-x}$ Sb crystals were increased from 0.071 to 5 .OMEGA.-cm at room temperature according to the increment of the composition ratio x. The mobilies of $Al_{x}$G $a_{1-x}$ Sb crystals varied with the composition ratio x resulted in the following three different regions of GaSb-like (0.leq.x.leq.0.3), intermediate (0.3.leq.x.leq.0.4) and AlSb-like (0.4.leq.x.leq.l).q.l).q.l).q.l).

• The Korean Society of Law and Medicine
• /
• v.10 no.1
• /
• pp.363-388
• /
• 2009

i) Das deutsche Arzneimittelgesetz(AMG) vom 24. 8. 1976 hat neben der Einf$\ddot{u}$hrung des Zulassungsverfahren f$\ddot{u}$r Arzneimittel anstelle des bisherigen Registrieungsverfahrens vor allem auf dem Gebiet des Haftungsrechts eine bedeutende Neuerung gebracht: die Gef$\ddot{a}$hrdungshaftung f$\ddot{u}$r den pharmazeutischen Unternehmer. Gem$\ddot{a}{\ss}$ $\S$84 AMG ist der pharmazeutische Unternehmer zum Schadensersatz verpflichtet. wenn infolge der Anwndung eines Arzneimittels ein Mensch get$\ddot{o}$tet oder K$\ddot{o}$rper oder die Gesundheit eines Menschen nicht unerheblich verletzt wird. Pharmazeutischer Unternehmer ist, wer das Arzneimittel unter seinem Namen in Verkehr bringt. ii) Die Ersatzpflicht des pharmazeutisches Unternehmers besteht jedoch nur in zwei F$\ddot{a}$llen: a) Das Arzneimittel hat bei bestimmungsgemm$\ddot{a}{\ss}$em Gebrauch sch$\ddot{a}$dliche Wirkungen, die $\ddot{u}$ber ein nach den Erkenntnissen der medizinischen Wissenschaft vertretbares Ma$\ss$ hinausgehen($\S$84 Abs. 1 Satz 2 Nr. 1 AMG). b) Der Schaden ist infolge einer nicht den Erkenntnissen der medizinischen Wissenschaft entsprechenden Kennzeichnung, Fachinformarion oder Gebrauchsinformation eingetreten($\S$84 Abs. 1 Satz 2 Nr. 2 AMG). iii) Mit dem 2. Schadensersatzrechts$\ddot{a}$nderungsgesetz ist, dem Konzept von $\S$6 Umwelthaftungsgesetz folgend, eine gesetzliche Kausalit$\ddot{a}$tsvermutung eingef$\ddot{u}$hrt worden. Ist das angewendete Arzneimittel nach den Gegebenheiten des Einzelfalls geeignet, den entstandenen Schaden zu verursachen, so soll vermutet werden, da$\ss$ das Arzneimittel auch den konkreten Schaden beim Anwender verursacht hat($\S$84 II AMG). Der pharmazeutische Unternehmer hat dann diese Vermutung zu wiederlegen. iv) Gem$\ddot{a}{\ss}$ $\S$94 AMG hat der pharmazeutische Unternehmer f$\ddot{a}$r seine Haftpflicht Deckungsvorsorge entweder durch eine Hafpflichtversicherung oder eine Freistellungs- oder Gew$\ddot{a}$hrleistungsverpflichtung eines Inl$\ddot{a}$ndischen Kreditinstituts zu treffen. v) Aber koreanisches Arzneimittelgesetz hat keine Gef$\ddot{a}$hrdungshaftung f$\ddot{u}$r Arzneimittelschaden. Es gibt nur Gefahrdungshaftung des Hersteller aufgrund des Produkthaftungsgesetzes, das auf das Arzneimittel Anwendung findet. Ich glaube, in Zukuft soll koreanisches AMG die Gef$\ddot{a}$hrdungshaftung f$\ddot{u}$r den pharmazeutischen Unternehmer regeln.