Search results for "BIP"
showing 10 items of 1908 documents
Quasi-digital conversion for resistive devices: application in GMR-based IC current sensors
2013
Resistive devices, including sensors, are used in a huge range of applications within different scenarios. When a complete system is considered, a quasi-digital output is often recommendable. If the conversion is operated at device level, some problems such as noise disturbs, insertion losses and so on, can be reduced. In this work, we describe a resistance-tofrequency (R-f) converter with a suggested application in low current monitoring by means of GiantMagnetoResistance (GMR) sensors. Specific devices have been designed and microfabricated. The system has been tested by means of discrete components with a PCB. The complete microsystem monolithic integration in a standard CMOS technology …
Automated Calculation Method to Determine the Output Power Based on the Frequency for Induction Heating IGBT Parallel Inverter
2007
The fact that some inverter topologies used in induction heating applications allow the soft switching working operation lets the progressive replacement of the MOSFET with the IGBT in high power inverters. This is due to two main reasons, the former is the IGBT reliability and the latter is the ratio defined as the price of the component per output power. In this article an automated method to determine the output power based on the frequency of an inverter build with different IGBT is described. To carry out this method is necessary to define the power cycle and to develop the calculation process which determines the energy losses in the working conditions of the resonant parallel inverte…
Noise and gain performance of PSA transistor series for personal communication systems vs. emitter number and operating conditions
1995
The booming market of communication system applications in the low microwave range put greater demands on the component performance at lower supply voltages and limited current consumption, as well as on production cost and integration level. In this work, we present the results of an extensive characterization activity carried out on several advanced polysilicon bipolar transistors as requested by the manufacturer. The devices were grouped according to their emitter finger number and were characterized over the 2-6 GHz frequency range in terms of noise, gain and scatterino parameters at different bias conditions. A comparative analysis has been performed to explore how the transistor perfo…
The occurrence of Dechlorane Plus and related norbornene-based flame retardants in Baltic wild salmon (Salmo salar)
2015
Twenty five Baltic wild salmon (Salmo salar) specimens were analysed for the content of Dechlorane-related compounds (DRCs). Out of the ten analysed DRCs, seven compounds were detected in the muscle tissues of salmon, including Dechlorane (Dec) 602, Dec 603, syn- and anti-stereoisomers of Dechlorane Plus (DP), Dechlorane Plus monoadduct (1,3-DPMA), hexachlorocyclopentadienyl-dibromocyclooctane (DBHCTD), and Mirex. The concentrations of Dec 604 and two DP dechlorinated compounds - decachloropentacyclooctadecadiene (Cl10DP) and undecachloropentacyclooctadecadiene (Cl11DP) - were below the limit of detection in all samples. The aggregated concentrations of DRCs (ΣDRC) were in the range of 551-…
Synthesis and structure verification of two previously uncharacterized pentachlorobiphenyls: PCB 108 and PCB 127
1992
Abstract The synthesis and structure verification of two previously uncharacterized polychlorinated biphenyl (PCB) congeners mono- ortho -substituted 2,3,3′,4,5′-pentachlorobiphenyl (PCB 108) and non- ortho -substituted 3,3′,4,5,5′-pentachlorobiphenyl (PCB 127) is described. The synthesis was done by the method of aromatic arylation in the presence of isopentyl nitrite. The purification and separation of the compounds was done by flash-chromatography on Al2O3- and charcoal columns. The structures were verified by 1H NMR, 13C NMR, IR and mass spectroscopy.
The use of blue tit eggs as a biomonitoring tool for organohalogenated pollutants in the European environment
2010
In the present study, large scale geographical variation in the occurrence of organohalogenated pollutants (OHPs) was investigated throughout Europe using eggs of a terrestrial resident passerine species, the blue tit (Cyanistes caeruleus). Blue tit eggs from 10 sampling locations, involving suburban, rural and remote areas, in 7 European countries were collected and analysed. Sum polychlorinated biphenyl (PCB) levels ranged from 150 ng/g lipid weight (lw) to 2003 ng/g lw. Sum polybrominated diphenyl ethers (PBDEs) ranged from 3.95 ng/g lw to 114 ng/g lw. As expected, PCB and PBDE concentrations were significantly higher in the sampled suburban locations compared to the rural and remote loc…
Polychlorinated organic compounds in the Arctic cod liver: trends and profiles
2000
Polychlorinated organic compounds (POCs) have been measured in Arctic cod liver from Vestertana Fjord for a period of 1987-1998. Significant decrease was observed for DDD (p = 0.043), alpha-HCH (p = 0.001), and gamma-HCH (lindane; p = 0.001). Contents of DDE, 2,3,7,8-tetrachlorodibenzofuran, PCBs, chlordanes, chloronaphthalenes, hexachlorobenzene and polychlorodiphenyl ethers had no significant trend. Contents of three hexa- and two heptachlorodibenzofurans and octachlorodibenzofuran increased slightly from 1987 to 1994, but then at very high rate from 1994 to 1998. Trends of HCHs, profiles of PCBs and levels of chlordanes are in accordance with atmospheric long range transport. The hexa-, …
Uptake rates of semipermeable membrane devices (SPMDs) for PCDDs, PCDFs and PCBs in water and sediment.
2000
Uptake rates of several PCDDs, PCDFs and PCBs were measured for semipermeable membrane devices (SPMDs) under controlled conditions in bulk water and sediment. The study was performed at 19 degrees C and 11 degrees C, and water and sediment concentrations were measured during the exposure. Linear uptake rates for specific PCDD/Fs and PCBs in 19 degrees C water varied from 34 to 111 l/m2 day and in 11 degrees C water from 8.8 to 96 l/m2 day for the whole SPMD. Uptake rates at 19 degrees C sediment ranged from 9.0 to 80 mgOC/m2 day and in 11 degrees C sediment, from 3.0 to 31, mgOC/m2 day. Partitioning of the compounds between membrane and lipid was also measured during the linear uptake phase…
Degradation half-life times of PCDDs, PCDFs and PCBs for environmental fate modeling.
2000
Literature search of the knowledge on the degradation of persistent organic pollutants (POPs) in environmental compartments air, water, soil and sediment was done in purpose to find properties of POPs of interest for modeling. One degradation process, hydrolysis (chemical degradation), was omitted as negligibly slow for POPs studied. The other two, photolysis and biodegradation processes, were considered separately in purpose to develop estimation procedures. The estimates can be given as pseudo first-order rate constants kP for photolysis and kB for biodegradation. For each compartment, an overall degradation rate is k(tot) = kP + kB and lifetime t(1/2) = ln 2/k(tot). The latter values, li…
Polychlorinated biphenyls and some pesticides in perch (Perca Fluviatilis) from inland waters of Latvia
1999
Polychlorinated biphenyls (PCBs), DDT - related substances, hexachlorocyclohexane (HCH) isomers and hexachlorobenzene (HCB) were analysed in perch (Perca fluviatilis) from Latvian lakes and rivers. DDE is present in the highest concentrations in all samples; 62–170 ng/g lipid weight in perch from rural areas and 460 ng/g in perch from the Riga area. Individual dominating PCB congeners were in the range 16–45 ng/g and 200–210 ng/g, respectively. The degree of contamination of rural areas in Latvia of these organohalogen substances is in the same range as in background areas in Sweden. Riga, the major urban area in Latvia, is shown to be more polluted with PCBs than other areas in Latvia.