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1
Content available remote Effects of human activities in the coastal zone of Laizhou Bay
100%
Wang M. , Han M. , Hui H. , Li Y.
Ecological Chemistry and Engineering. S
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2021
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tom Vol. 28, nr 2
219--227
EN
The serious destruction of resources and environment in Laizhou Bay has attracted extensive attention of researchers. This study mainly analysed the changes of fish structure and environment in the coastal zone of Laizhou Bay caused by human activities. By consulting literatures and field measurements, the changes of dominant fish species, coastline and sea water intrusion were analysed. The results showed that dominant fish species in Laizhou Bay change from high-economic species to low-economic species under the influence of human activities, and the coastline erosion was serious, and the area of sea water intrusion was also increasing year by year. It is concluded from the research results that human activities had a significant impact on the structure of fish school and the environment. It is necessary to arrange human activities in an appropriate amount to reduce the overexploitation of resources in order to restore the fishery resources and environment in Laizhou Bay.
2
Content available Estimation of the upper flammability limits for alkanes in air at increased pressures
88%
Wan X. , Wang M. , Cao C. , Zhao S. , Song Z.
Polish Journal of Chemical Technology
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2022
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tom Vol. 24, nr 2
35--41
EN
A method is proposed to predict the upper flammability limits for alkanes in air at increased pressures. The upper flammability limits for methane, ethane, propane and n-butane/air mixtures at ambient temperature and initial pressure of 0.3 MPa–2.0 MPa are identified through the adiabatic flame temperature calculation model. The association of calculated adiabatic flame temperature with pressure is presented to determine the upper flammability limit. Research shows the good agreement between the forecast upper flammability limits with pressure dependence and the experimental upper flammability limit values. The average relative error of the estimated upper flammability limits for alkanes in air at high pressures reaches 2.52%.
3
Content available Current status of phenolic pollution in urban lakes and its toxicity to cells : a case study of Xi’an, China
88%
Wang M. , Zhang Y. , Sun J. , Huang C. , Zhai H.
Archives of Environmental Protection
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2023
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tom Vol. 49, no 1
63--73
EN
Liquid chromatography-mass spectrometry was used to detect and analyze phenolic compounds in the surface waters of four urban lakes in Xi’an – Hancheng Lake, Xingqing Lake, Nanhu Lake, and Taohuatan Lake. A total of 5 phenolic compounds were detected from the water samples, with a concentration range of ND-100.32 ng/L, of which bisphenol A (BPA) and nonyl phenol (NP) were the main types of phenolic compounds pollution in the four lakes. Pearson correlation analysis was used to analyze the concentration of phenolic compounds in the lake waters of Xi’an City and the water quality indicators COD, TP, NH3 -N, DO, and pH during the same period. It was found that there was a significant positive relationship between the concentration of BPA and COD, the concentration of estradiol (17-beta-E2), estrone (E1) and TP and TN, the concentration of octylphenol (4-t-OP) and pH. The ecological risk assessment (ERA) shows that the concentration of BPA, 4-t-OP and NP in the lakes is at a medium risk level( is between 0.1–1), and that of E1 is at a high risk level (is greater than 1). Female cells (breast cancer cells) and male germ cells (testis cells) of mice were used as research objects to explore BPA and NP Toxic effect on mouse germ cells. BPA and NP at a concentration of 10-8 mol/L were found to have the most value-inducing effect on MCF-7 breast cancer cells positive for estrogen receptor. Obviously, both BPA and NP can induce the proliferation of testicular Sertoli cells.
4
Content available remote High-Performance Workwear for Coal Miners in Northern China: Design and Performance Evaluation
88%
Ke Y. , Zheng Q. , Wang F. , Wang M. , Wang Y.
Autex Research Journal
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2022
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tom Vol. 22, no. 2
155--162
EN
The design of workwear has significant effects on worker performance. However, the current workwear for coal miners in Northern China is poor in fitness and thermal comfort. In this study, new workwear (NEW) for coal miners was developed with the design features providing better cold protection and movement comfort performance, as compared with a commonly worn workwear (CON). To evaluate the effectiveness of NEW, we conducted human trials which were performed using simulated work movements (i.e., sitting, shoveling, squatting, and crawling) in a climate chamber (10°C, 75% RH). Physiological measurements and perceptual responses were obtained. The results demonstrated that the local skin temperatures at chest, scapula, thigh, and calf; mean skin temperatures,; and thermal comfort in NEW were significantly higher than those in CON. NEW also exerted an improvement in enhancing movement comfort. We conclude that NEW could meet well with the cold protective and mobility requirements.
5
Content available remote Evaluation of the influence of high‑order ionospheric delay on GPS undifferenced and uncombined precise point positioning
88%
Tian X. , Chai H. , Yin X. , Pan Z. , Wang M.
Acta Geophysica
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2023
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tom Vol. 71, no. 4
1983--1994
EN
High active ionosphere periods have a sizeable ionospheric delay in signal transmission. The high-order ionospheric delay (HOI) severely influences GPS precise point positioning (PPP). The phase-smoothed pseudorange method is used to calculate the slant total electron content, and IGRF-13 (the 13th International Geomagnetic Reference Field) is introduced to calculate high-order ionospheric delay. UDUC PPP with HOI constraint is realized, and the solutions without and with HOI correction are obtained. The time series of the positioning residuals are used to explore the white noise and zero mean characteristics of code and phase. Based on the Jarque–Bera test and t test, the influence of HOI on PPP residuals in the active ionosphere period is researched. The results show that HOI is at the millimeter level, and its influence on UDUC PPP is at the submillimeter level. Thus, HOI needs to be considered in UDUC PPP for the millimeter application.
6
Content available remote Design and Performance Evaluation of Protective Clothing for Emergency Rescue
75%
Zhang H. , Zheng Q. , Ke Y. , Wang H. , Wang M. , Ye Y.
Autex Research Journal
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2022
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tom Vol. 22, no. 1
1--10
EN
Protective clothing is very important to guarantee the safety of emergency rescuers. And proper construction design of clothing will improve the rescue efficacy. This study developed a new set of emergency rescue protective clothing (NC) and evaluated its performance. Clothing fit test, freedom of movement, and rationality of pocket tests were conducted. The results showed that the amount of slippage at the hem, waist of pants, and leg opening of NC has been greatly reduced. The NC had provided better cloth fit and dynamic comfort. The storage capacity of the pockets had been increased, the position and angle design of the pocket made it easier to take and keep the rescue tools.
7
Content available remote Hydrochemical characteristics and water quality assessment of groundwater in the Yishu River basin
75%
Liu J. , Wang M. , Gao Z. , Chen Q. , Wu G. , Li F.
Acta Geophysica
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2020
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tom Vol. 68, no. 3
877--889
EN
Groundwater is the primary source of water for human development in the Yishu River basin, and therefore characterizing groundwater quality is essential for sustainable development of groundwater resources in the region. This study aimed to determine the hydrochemical characteristics and water quality of groundwater in the Yishu River basin by sampling 45 wells in October 2016 and May 2017. Hydrochemical characteristics of groundwater were determined using integrated hydrochemical analysis and the groundwater quality was evaluated based on the water quality index (WQI). Groundwater of the Yishu River basin was characterized as weak alkaline hard water with mean concentrations of total hardness and total dissolved solids of less than 500 mg L−1 and 1000 mg L−1, respectively, and the principal chemical components of groundwater were higher in 2016 than in 2017. A Piper diagram showed that 64.4% of the water samples contained Ca–HCO3 type water and 27% contained mixed water (27%). The dominant processes driving the chemical composition of groundwater were found to be dissolution of silicate and carbonate minerals and cation exchange. The saturation index indicated that carbonate minerals were supersaturated, whereas gypsum, fuorite, and halite were unsaturated. The WQI indicated good groundwater quality in the Yishu River basin, with only one water sample classifed as having "poor" water quality in 2016 and 2017, respectively. However, these samples contained high nitrate concentrations (>200 mg L−1), which may be the result of domestic sewage discharge and/or the use of agricultural fertilizers.
8
Content available remote Simultaneous determination of ginkgolide A, B, C, bilobalide and rutin in rat plasma by LC-MS/MS and its application to a pharmacokinetic study
63%
Hu B. , Sun Y. , Wang M. , He Z. , Chen S. , Qi D. , Ge Z. , Fan L. , Chen J. , Wei Y.
Acta Chromatographica
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2022
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tom Vol. 34, no. 4
386--393
EN
A reliable LC-MS/MS method for the determination of five bioactive constituents (bilobalide, BLL; ginkgolide A, GLA; ginkgolide B, GLB; ginkgolide C, GLC; rutin) of Ginkgo biloba leaf extracts (GBE) in rat plasma was established, fully validated and applied to an intragastric pharmacokinetic study of a preparation of GBE in rat. Samples were extracted with ethyl acetate. C18 column was selected as analytical column in this method. Mobile phase was water with 0.01% formic acid and acetonitrile. Quantification was performed in negative multiple-reaction monitoring mode. Matrix instability of terpene lactones was noticed and hydrochloric acid was used as a stabilizer. This method showed good precision and accuracy, recovery was reproducible and matrix effect was negligible. Among four terpene lactones, BLL had the highest exposure and the shortest terminal half-life, GLA and GLB had lower exposure and longer terminal half-life, the exposure of GLC was lowest and its terminal half-life was the maximum, and all of them showed rapid absorption. This study provides a reference for determination of terpene lactones and flavonol glycoside prototypes in GBE and offers pharmacokinetic data of flavonol glycoside prototype in GBE.
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