This paper presents the design of a front-end circuit for monolithic active pixel sensors. The circuit operates with a sensor featuring a small, low-capacitance (< 2 fF) collection electrode and is ...integrated in the DPTS chip, a proof-of-principle prototype of 1.5 mm × 1.5 mm including a matrix of 32 × 32 pixels with a pitch of 15 μm. The chip is implemented in the 65 nm imaging technology from the Tower Partners Semiconductor Co. foundry and was developed in the framework of the EP-R&D program at CERN to explore this technology for particle detection. The front-end circuit has an area of 42 μm 2 and can operate with a power consumption as low as 12 nW. Measurements on the prototype relevant to the front-end will be shown to support its design.
The contents of 49 trace elements in sub-bituminous Pernik coals and their waste products from preparation and combustion processes were investigated. The studied coals have trace element contents ...higher than the respective Clarke values for brown coals and some of them may pose environmental concerns. The elements Li, Rb, Cs, Ba, Sc, Y, La, Ce, Nd, Sm, Eu, Er, Ga, Zr, Sn, V, Nb, Ta, W, F, Cu, Zn, In, Pb, Cr, Co, Ni, and Th in the feed coals have concentrations that exceed twice the Clarke values. Most element contents in bottom ash are enriched compared with those in feed coal. Some of the volatile elements are equal or significantly depleted including Sn, Mo, Sb, F, Bi, Cd, Ge, and Pb. Fly ash has higher contents of Ga, Zr, Hf, Sn, V, Nb, Mo, and F in comparison with bottom ash. Most elements have a significant positive correlation with ash yield, indicating their inorganic association. The mixed wastes (coal slurry, bottom ash, and fly ash) in the disposal pond are slightly depleted of most of the elements studied with the exclusion of Cl, Ba, and Br. The Pernik coals and their waste products are unpromising for the extraction of REY due to their low element contents.
Complexes of poly(propylene imine) dendrimers D8DAB-dendr-(NH
2)
8 and D32 DAB-dendr-(NH
2)
32 were prepared by interaction of the dendrimers with transition metal salts such as FeCl
3.6H
2O; CoCl
...2.6H
2O; CuCl
2.2H
2O; VOSO
4.5H
2O; Na
2MoO
4.2H
2O and Na
2WO
4.2H
2O at room temperature in aqueous solutions. The content of metal ions in the complexes was found to be from 8.2 to 69.6
mg metal ion/g polymer carrier. The complexes were characterized by using IR, UV–VIS, Moessbauer spectroscopy and EPR. The anticipated co-ordination structure of the compounds was suggested. It was found that the order of the catalytic activity of the complexes of poly(propylene imine) dendrimers D8 and D32 in the reaction of epoxidation of cyclohexene with organic hydroperoxides such as
tert-butyl hydroperoxide (
t-BHP), ethylbenzene hydroperoxide (EBHP) and cumene hydroperoxide (CHP) was as follows: D32-MoО
2
2+>D32-VО
2+>D32-WО
2
2+ >
D32-Co
2+
>
D32-Cu
2+>D32-Fe
3+. The order of reactivity of organic hydroperoxides in the reaction studied was:
t-BHP
>
EBHP
>
CHP.
Purpose: To determine whether the wearing time of contact lenses affects the condition of the meibomian glands and the tear film breakup time.
Material and methods: This is a cross-sectional study ...involving 150 eyes ( 75 patients) with an age between 18 to 65 years. Five groups were allocated, with distribution criteria being the soft contact lenses wearing time: up to 5 years, from 6 to 10 years, from 11 to 20 years and more than 20 years. All subjects used soft contact lenses daily, at least 5 hours a day and 4 days a week. All patients underwent a thorough ophthalmic examination and non invasive tear film breakup time (NIBUT), and meibomian gland loss (MGL) investigated with Oculus Keratograph 5 M.
Results: A statistically significant relation with the soft contact lenses wearing time has been found for the indicator MGL,% (U) (p = 0.025). In the general study of male and female patients, a significant association was only observed in female patients (p = 0.04). A statistically significant relation to the soft contact lenses wearing time has been found for the indicators NIBUT 1, s ( P=0.035) и NIBUT Av, s ( P=0.023). The same relation has been found only in female patients - NIBUT 1, s ( P=0.035 и NIBUT Av, s ( P=0.023).
Conclusion: Long-term contact lenses wearing is proportional to the change in gland function and may contribute to the development of dry eye syndrome.
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