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For problems of being easily affected by environment, low detection decision and poor stability in traditional methane detection system, a distributed multi-point laser methane detection system was designed based on tunable diode laser absorption spectroscopy technology and space division multiplexing technology. The system adopts distributed feedback semiconductor laser with wavelength of 1 653.7 nm as light source, uses ratio of the second harmonic and the first harmonic gotten by harmonic detection to invert methane concentration, and employs 1/8 beam splitter and reference air chamber to realize real-time multi-point methane concentration detection. The system has been tested in laboratory. The test results show that the system has high accuracy and good stability, can realize monitoring points within 10 km effectively covered, and measurement error is less than 2% when methane concentration is 2.00%-85.0%.

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Background: Hemodialysis therapy has been used in the treatment of acute alcohol intoxication for many years, especially acute severe alcohol intoxication. Objectives: This study aimed to evaluate whether the combination of conventional treatment and naloxone with hemodialysis has advantages over conventional treatment and naloxone alone in patients with acute severe alcohol intoxication. Methods: After searching 12 databases and 2 clinical trial centers. According to the established inclusion and exclusion criteria, the qualified literatures were screened. The outcome indicators were length of hospital stay, coma time, time of symptom disappearance, the overall complication rate, the incidence of pancreatitis, the incidence of aspiration pneumonia, the incidence of hepatic and renal dysfunction. Analysis was performed using Revman 5.3. Results: This meta-analysis included 13 studies, including 932 subjects. In the treatment of acute severe alcohol intoxication, the use of hemodialysis on the basis of conventional treatment and naloxone could reduce the length of hospital stay (WMD = −15.16, 95% CI: −17.45 to −12.86, p < 0.001) in hours and (WMD = −4.89, 95% CI: −5.53 to −4.25, p < 0.001) in days; coma time (WMD = −5.43, 95% CI: −6.43 to −4.43, p < 0.001); time of symptom disappearance (WMD = −3.92, 95% CI: −5.37 to −2.47, p < 0.001); the overall complication rate (RR = 0.39, 95% CI: 0.28–0.55, p < 0.001); the incidence of pancreatitis (RR = 0.14, 95% CI: 0.05–0.43, p = 0.0006); the incidence of aspiration pneumonia (RR = 0.15, 95% CI: 0.04–0.66, p = 0.01), and the incidence of hepatic and renal dysfunction (RR = 0.21, 95% CI: 0.06–0.72, p = 0.01). Conclusions: It can be concluded that compared with the use of conventional treatment and naloxone alone, the use of hemodialysis on the basis of conventional treatment and naloxone for acute severe alcohol intoxication can reduce the length of hospital stay, coma time, time of symptom disappearance, and the incidence of some complications rate. Large scale, multicenter, and well-designed RCTs are needed in the future to prove our conclusions. [ABSTRACT FROM AUTHOR]

In view of problems of rotor eccentricity, high temperature, excess vibration and blocking of drain-pipe in motors of traditional drainage devices of coal mine, a fault monitoring system of mine drainage device based on LabVIEW was designed. The system uses LabVIEW software and data acquisition card to collect data such as pipe flow, pipe pressure, vacuum degree of water pump and temperature and vibration of motor of the mine drainage device, and makes domain analysis, amplitude spectrum analysis and fault diagnosis of vibration signals, so as to realize early warning for over-limit signals.