2,959 research outputs found

    Gas Emission Control on Longwall Panels at the Vorkuta Coal Mines

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    The characteristics of geological conditions and mining technology at the coal mines of Coal Stock Company Vorkutaugol are given in the article. Information about longwall panel ventilation schemes and problems caused by high methane emission is also presented. The results of experiments at longwall panels using the methane emission control ventilation complex are described as well as ways of isolating gob methane removal. Other topics include the methane emission control ventilation complex consisted of drainage entry, an isolating wall with windows, mixing chambers and regulating stoppings. As results of experiments have shown, the most effective gas emission control methods were: the application of gas sucking fans for the isolated gob methane removal, and isolating walls at the line exposed to the gob. Encouraging results were obtained by use of two-entry mining system with yielding pillar between entries, homotropal ventilation and isolated methane removal from the gob

    IoT based system for real-time monitoring the hydrogen-ion activity in water bodies

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    The paper presents design and principle of operation of a mobile combined pH meter. Sensor’s network underlying the IoT system for monitoring water bodies hydrogen ions activity in real time was demonstrated. The measuring device was tested on liquids with different pH levels. The obtained measurement results were compared using a stationary pH meter OHAUS Starter 3100

    Measurement of the e+eK+Kπ+πe^+e^- \to K^+K^-\pi^+\pi^- cross section with the CMD-3 detector at the VEPP-2000 collider

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    The process e+eK+Kπ+πe^+e^- \to K^+K^-\pi^+\pi^- has been studied in the center-of-mass energy range from 1500 to 2000\,MeV using a data sample of 23 pb1^{-1} collected with the CMD-3 detector at the VEPP-2000 e+ee^+e^- collider. Using about 24000 selected events, the e+eK+Kπ+πe^+e^- \to K^+K^-\pi^+\pi^- cross section has been measured with a systematic uncertainty decreasing from 11.7\% at 1500-1600\,MeV to 6.1\% above 1800\,MeV. A preliminary study of K+Kπ+πK^+K^-\pi^+\pi^- production dynamics has been performed

    Study of the process e+eppˉe^+e^-\to p\bar{p} in the c.m. energy range from threshold to 2 GeV with the CMD-3 detector

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    Using a data sample of 6.8 pb1^{-1} collected with the CMD-3 detector at the VEPP-2000 e+ee^+e^- collider we select about 2700 events of the e+eppˉe^+e^- \to p\bar{p} process and measure its cross section at 12 energy ponts with about 6\% systematic uncertainty. From the angular distribution of produced nucleons we obtain the ratio GE/GM=1.49±0.23±0.30|G_{E}/G_{M}| = 1.49 \pm 0.23 \pm 0.30

    Measurement of the Pion Form Factor in the Energy Range 1.04-1.38 GeV with the CMD-2 Detector

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    The cross section for the process e+eπ+πe^+e^-\to\pi^+\pi^- is measured in the c.m. energy range 1.04-1.38 GeV from 995 000 selected collinear events including 860000 e+ee^+e^- events, 82000 μ+μ\mu^+\mu^- events, and 33000 π+π\pi^+\pi^- events. The systematic and statistical errors of measuring the pion form factor are equal to 1.2-4.2 and 5-13%, respectively.Comment: 5 pages, 2 figure
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