The objective of this study was to determine the effect of advanced oxidation process with the use of Fenton’s reaction on the effectiveness of anaerobic treatment of wastewaters originating from the wood industry that were characterized by a high concentration of formaldehyde. Experiments were established to analyze changes in COD content and in the concentration of formaldehyde in treated wastewaters, additional analyses were carried out to assay quantitative and qualitative changes in the biogas produced. The first stage of the experiment involved analyses of the effectiveness of the tested wastewaters treatment only in the process of methane fermentation. At the second stage of the experiment, the biological process was preceded by chemical pre-treatment of wastewaters with Fenton’s reagent. The conducted study proved that the investigated variants of chemical pre-treatment of wastewaters had a significant effect on increasing the total biogas production. In contrast, no significant effect of the applied technology was demonstrated on changes in the concentration of the analyzed contaminants in the treated wastewaters.
The aim of the conducted research was to determine the possibilities of using the biomass of macroalgae obtained from Puck Bay during May-September season in biogas production process. Model respirometry chambers were used to determine the amount of produced biogas and examine its quality composition. Depending on the month in which the algal biomass was obtained, the experiments were divided into five stages. In each stage, the effectiveness of the biogas production process was tested for the applied loads in model fermentation chambers in the range from 1.0 kg DOM/m3 · d to 3.0 kg DOM/m3 · d. During the experiments it was found that the efficiency of biogas production varied from 205 dm3/kg DOM to 407 dm3/kg DOM depending on the month of the vegetation season and the applied organic matter load in the chamber. Methane content was very high and ranged from 63% to 74%.
Most systems used in quantum physics experiments require the efficient and simultaneous recording different multi-photon coincidence detection events. In such experiments, the single-photon gated counting systems can be applicable. The main sources of errors in these systems are both instability of the clock source and their imperfect synchronization with the excitation source. Below, we propose a solution for improvement of the metrological parameters of such measuring systems. Thus, we designed a novel integrated circuit dedicated to registration of signals from a photon number resolving detectors including a phase synchronizer module. This paper presents the architecture of a high-resolution (~60 ps) digital phase synchronizer module cooperating with a multi-channel coincidence counter. The main characteristic feature of the presented system is its ability to fast synchronization (requiring only one clock period) with the measuring process. Therefore, it is designed to work with various excitation sources of a very wide frequency range. Implementation of the phase synchronizer module in an FPGA device enabled to reduce the synchronization error value from 2.857 ns to 214.8 ps.
The designing process of high resolution time interval measurement systems creates many problems that need to be eliminated. The problems are: the latch error, the nonlinearity conversion, the different duty cycle coefficient of the clock signal, and the clock signal jitter. Factors listed above affect the result of measurement. The FPGA (Field Programmable Gate Array) structure also imposes some restrictions, especially when a tapped delay line is constructed. The article describes the high resolution time-to-digital converter, implemented in a FPGA structure, and the types of errors that appear there. The method of minimization and processing of data to reduce the influence of errors on the measurement is also described.
The ultrasonic flowmeter which is described in this paper, measures the transit of time of an ultrasonic pulse. This device consists of two ultrasonic transducers and a high resolution time interval measurement module. An ultrasonic transducer emits a characteristic wave packet (transmit mode). When the transducer is in receive mode, a characteristic wave packet is formed and it is connected to the time interval measurement module inputs. The time interval measurement module allows registration of transit time differences of a few pulses in the packet. In practice, during a single measuring cycle a few time-stamps are registered. Moreover, the measurement process is also synchronous and, by applying the statistics, the time interval measurement uncertainty improves even in a single measurement. In this article, besides a detailed discussion on the principle of operation of the ultrasonic flowmeter implemented in the FPGA structure, also the test results are presented and discussed
W obliczu rewolucji technologii informatycznych badacze nauk społecznych mają przed sobą nie lada wyzwanie. Oto bowiem wraz ze zwiększającą się popularnością Internetu pojawiły się ogromne ilości danych zawierających opinie, poglądy i zainteresowania jego użytkowników. Chociaż analiza tych danych stawia przed badaczami poważne problemy metodologiczne, za ich użyciem przemawia fascynujący materiał powstający bez ingerencji badaczy. Dużą część tego materiału stanowią dane z najpopularniejszej na świecie wyszukiwarki Google. Co minutę jej użytkownicy ze wszystkich miejsc na świecie zadają ponad 3 miliony zapytań, które są następnie klasyﬁkowane i udostępniane za pomocą aktualizowanych na bieżąco narzędzi. W artykule tym omówione są próby adaptacji tych danych do potrzeb nauk społecznych, a także dotychczasowe badania na ten temat. Omówione są także praktyczne aspekty pracy z narzędziami Google’a: Google Trends oraz Google Keyword Planner. Artykuł jest przeznaczony przede wszystkim dla badaczy nauk społecznych zainteresowanych internetowymi źródłami Big Data oraz wykorzystaniem tych danych w pracy naukowej.
Respiratory disturbances frequently accompany stuttering. Their influence on lung ventilation can be assessed by measurement of the end-tidal CO2 concentration (EtCO2). The effectiveness of the CO2-based visual feedback method of breath regulation (VF) designed for stuttering therapy was tested in this study. The aim of the study was to answer the question if the VF helps to reduce respiratory disturbances in stuttering and increase speech fluency. 20 stuttering volunteers aged 13-45 years took part in the 3-parts test consisting of: 1. speaking without any techniques improving speech fluency, 2. learning the VF method, 3. VF-assisted speaking. The CO2/time signal and an acoustic signal of an utterance were recorded during the test. Significant increase of FE - the factor of breath ergonomics during speaking (based on both signals), from 47% to 71% (P < 0.01), and significant decrease of %SS - the percent of syllables stuttered, from 14% to 10% (P < 0.01) were received for VF-assisted utterances compared to the utterances without VF assistance. The results indicate that the VF can help to eliminate respiratory disturbances in stuttering and increase speech fluency.