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1.
J Hazard Mater ; 455: 131619, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37207484

RESUMO

Supercritical water gasification (SCWG) technology can convert oily sludge into hydrogen-rich gas. To achieve high gasification efficiency of oily sludge with a high oil concentration under mild conditions, a two-step method involving a desorption process and a catalytic gasification process using Raney-Ni catalyst was investigated. High oil removal efficiency (99.57%) and carbon gasification efficiency (93.87%) were achieved. The lowest wastewater total organic carbon, oil content, and carbon content in the solid residues were 4.88 ppm, 0.08% and 0.88%, respectively, using a gasification temperature of 600 °C, treatment concentration of 1.11 wt%, gasification time of 70.7 s, and the optimal desorption temperature of 390 °C. The main organic carbon component in the solid residues was cellulose, which is environmentally safe. As the treatment concentration increased, the two-step method outperformed the single-step method. The mechanism for the two-step SCWG of oily sludge was revealed. In the first step, supercritical water is used in the desorption unit to achieve a high oil removal efficiency with few liquid products generated. In the second step, the Raney-Ni catalyst promotes efficient gasification of high-concentration oil at a low temperature. This research provides valuable insights into the effective SCWG of oily sludge at a low temperature.

2.
Front Endocrinol (Lausanne) ; 13: 875678, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35957840

RESUMO

Background: Identification of the high risk population for osteoporosis and timely prevention are the best strategies at present. Detailed epidemiological investigation in a well-defined population is necessary to explore the population-based characteristics and risk factors of osteoporosis, thus to facilitate better prevention programs. Method: In this prospective cross-sectional study, 1423 questionnaires were given out to the urban residents (female ≥ 40 years of age, male ≥50 years) who lived in the 27 Elderly-Care Inns interspersed among the seven central urban areas of Beijing. All participants were voluntary and underwent routine physical examination and spine and hip BMD measurements using the DXA instrument. The study protocols were approved by the Medical Ethics Committee of Dongzhimen Hospital, Beijing University of Chinese Medicine (JDZX2015079). Results: Altogether 1407 participants fulfilled the survey. Among 359 men, the prevalence of osteoporosis, osteopenia, and normal BMD were 18.1%, 56.6%, and 25.3%, respectively; among 1048 women, the corresponding figures were 40.3%, 42.8%, and 16.9%, respectively. After adjustment of age and BMI, both hands grip strength, height loss over 3 cm, serum levels of ß-CTx, PINP, and OST were the independent risk factors for osteoporosis in both men and women; besides, familial Alzheimer's disease history in men; and history of steatohepatitis and fracture, serum levels of PTH and ALT, age of menarche, age of menopause, and duration of menstruation in women were also risk factors of osteoporosis. In both genders, the cost-effective method, which adopted both hands grip strength, height loss over 3 cm, and medical history, indicated a good predictive ability to evaluate the risk of osteoporosis (in men AUC=0.730, 95%CI=0.642~0.817; in women AUC=0.769, 95%CI=0.724~0.813). Conclusions: In the population of elderly Beijing urban residents in Elderly-Care Inns, the prevalence of osteoporosis in women is higher than that in men and increases with aging more rapidly; the prevalence of osteopenia in men is higher than in women. The cost-effective method, including both hands grip strength, height loss over 3 cm, and familial Alzheimer's disease history in men; fracture and steatohepatitis history as well as menstrual history in women is recommended in identifying the high-risk subjects for osteoporosis.


Assuntos
Doença de Alzheimer , Doenças Ósseas Metabólicas , Fígado Gorduroso , Fraturas Ósseas , Osteoporose , Absorciometria de Fóton/métodos , Idoso , Densidade Óssea , Estudos Transversais , Feminino , Fraturas Ósseas/epidemiologia , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/etiologia , Estudos Prospectivos , Inquéritos e Questionários , População Urbana
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