Sudden emission and casualty accidents caused by abnormal enrichment of hydrogen sulfide (HS) in coal mines are becoming frequent increasingly, causing major casualties and environmental pollution. Scholars in various countries have developed various measuring devices for hydrogen sulfide content in coal and rock formations and their calculation methods. The existing prevention and control technologies of HS in coal mines were summarized in various countries. According to the distribution characteristics, occurrence modes, and emission forms of HS in coal mines, the prevention and control technologies of HS in coal-bearing strata, airflow in tunnel, and underground water body are mainly introduced. Analyzed the effects of different ventilation systems on prevention and control of HS, which include conventional ventilation system, partial homotropal ventilation system, and full homotropal ventilation system. The methods used mainly include neutralization by injecting alkalizer through drilling in coal seams with high pressure, spraying alkalizer in tunnel, attenuation by increasing wind amount, changing the ventilation method, pumping, dredging, and blocking the water that contains HS as well as comprehensive prevention and control method. The basic agents adopted mainly include sodium carbonate (the mass percentage concentration is about 0.5% ~ 3.0%) and sodium bicarbonate solution, and some basic solution is added by an additive, such as surfactant, Fenton reagent, sodium dodecyl benzene sulfonate, sodium hypochlorite, or chloramine-T. The treatment effect and the main problems of each prevention and control technology are analyzed, and a comprehensive method of prevention and control techniques of HS in coal mines is proposed. According to current technological level as well as the cost, the effective prevention and control techniques of HS should take the occurrence, distribution, and emission forms of HS in coal mines as well as the content into consideration.
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http://dx.doi.org/10.1155/2019/8719260 | DOI Listing |
Front Sports Act Living
December 2024
Department of PE and Sports Science, School of Physical Education, Sport Science and Dietetics, University of Thessaly, Volos, Greece.
Unlabelled: Aquaticity is an important parameter of human aquatic performance and behavior and can be objectively assessed by the aquaticity assessment test. Low aquaticity score can unveil a person's high risk in the water while it could dictate the specific characteristics that need to be addressed or developed for improving water competence.
Aim: The aim of the current study was to assess whether human aquaticity can be developed by systematic exercise and which type of training is more effective in improving aquaticity score.
Front Psychol
December 2024
Guilin Tobacco Company of Guangxi Zhuang Autonomous Region, Guilin, China.
Background: Smoking is highly prevalent among HIV-infected individuals and is associated with high morbidity and mortality. Studies on smoking among HIV-infected individuals in China, especially compared to uninfected individuals, are scarce.
Purpose: This study aimed to investigate and compare the prevalence and factors associated with smoking between HIV-infected and uninfected men in Guilin, China.
Germs
September 2024
MD, MPH, PhD, Department of Public Health, Faculty of Medicine, Universitas Islam Indonesia, Kaliurang Street KM 14.5 Yogyakarta 55584, Indonesia.
Introduction: Dengue infection poses a serious threat to global public health, including Indonesia. The rapid spread and significant economic impact are crucial concerns for control efforts. Investigating risk factors of dengue virus infection is necessary to formulate effective strategies, particularly at the household level.
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September 2024
MD, FESPCH, Prof., General Practitioner, Röntgenstr. 2 82152 Martinsried, Germany.
High quality research is critical for evidence-based decision making in public health and fundamental to maintain progress and trust in immunization programs in Europe. In 2024 the European Centre for Disease Prevention and Control (ECDC) conducted an update of the 2020 systematic review to capture more recent evidence on of the efficacy, effectiveness of influenza vaccines in individuals aged 18 years and older in the prevention of laboratory-confirmed influenza. While this report was highly anticipated due to the strength of the protocol and processes put in place, during our assessment, we expressed two chief concerns.
View Article and Find Full Text PDFCureus
December 2024
Cardiology, Pakistan Navy Station (PNS) Shifa, Karachi, PAK.
Colchicine, a long-established anti-inflammatory medication, has emerged as a potential therapeutic agent for secondary prevention of stroke. This systematic review and meta-analysis aimed to evaluate the efficacy and safety of colchicine in preventing secondary stroke by comprehensively synthesizing available evidence. A systematic literature search was conducted across multiple electronic databases from inception to November 15, 2024, using comprehensive search strategies.
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