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1

Atmospheric emissions of As, Sb, and Se from coal combustion in shandong province, 2005-2014

100%
Fan J., Wang Y.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 6
The emissions of hazardous trace elements have gained considerable attention because of their negative impacts on local air quality, regional environmental health, and ecological risks. Shandong Province has beenconsidered to be the top provincial emitter of Sb, As, and Se in China owing to rapid economic development and its energy consumption structure (mainly coal). In this study we investigate the atmospheric emissions of Sb, As, and Se from coal combustion in Shandong from 2005 to 2014, and we analyze a scenario for future emissions from coal-fired power plants. The inventory is based on the following parameters: coal consumption, economic sectors, boiler types, and air pollution control technologies. Results indicate that the calculated provincial total emissions of Sb, As, and Se from coal combustion in 2005 were estimated at 40.26, 246.5, and 255.9 t, respectively, and increased to 51.36, 311.9, and 313.9 t by 2014 with annual growth rates of 2.75%, 2.65%, and 2.27%. Industrial use was the largest single sector, accounting for nearly 83.2%, 82.6%, and 74.2% of the provincial total emissions for Sb, As, and Se in 2014, respectively. The emissions from coal-fired power plants have been controlled by the installation of flue gas desulfurization systems. In addition, scenario analysis shows that Sb and As emissions from coal-fired power plants will decrease in the future in a high-efficiency control technology scenario. However, Se emissions in 2030 will still be higher than in 2014. This study demonstrates the importance of assessing the effectiveness of control measures and supplying necessary suggestions for managing coal combustion in Shandong.
2

A ship network dynamic routing algorithm based on vector network

100%
Zhao J., Fan J.
Polish Maritime Research
|
2018
|
tom 25
|
nr Special Issue S2
n view of the characteristics of low speed mobile ship network, strong network dynamics and large signal interference, this paper proposes a low-rate mobile sensor network routing algorithm. In mobile wireless sensor networks, network topology changes frequently is a new challenge for resource constrained sensor node. Constantly updated network topology, sensor nodes need to exchange data frequently in order to maintain fresh route, resulting in sensor nodes consume a lot of energy. To solve this problem, to reduce control overhead is considered to be an effctive strategy. In this paper, we present a vector network-based dynamic routes (VNDR) scheme aims to minimize the control cost of the sensor nodes. We propose data exchange based on binary-coded vector address to reduce the control cost, moreover, we present a set of communication rules that govern the routes search procedure thereby requiring little cost of packet analysis to determine the next hop of node. VNDR performance was compared with well known scheme such as SPIN and DD. Simulation results show that, our VNDR scheme reduced the network control overhead and improved network lifetime
3

Comparison of soil microbial biomass and enzyme activities among three alpine grassland types in Northern Tibet

81%
Lu X., Fan J., Yan Y., Wang X.
Polish Journal of Environmental Studies
|
2013
|
tom 22
|
nr 2
Soil microbial biomass and enzyme activities have an important influence on nutrient cycling. The temporal variation in soil microbial biomass C, N, and enzyme activities during the growing season were determined under three different alpine grasslands in Northern Tibet. The results showed that soil microbial biomass C, and N contents and enzyme activities of the alpine meadow (AM) and the alpine meadow steppe (AMS) sites were much higher than those of the alpine steppe (AS) site. Soil microbial biomass C, N variations were not significantly correlated with the soil temperature and moisture, except that microbial biomass N seemed associated with the microsite where soil temperature was higher. Our results demonstrate that soil temperature was one of most important factors explaining the seasonal variation of microbial biomass N, but how the alpine grassland ecosystem's type affects microbial biomass C, N and enzyme activity are still needed to be clarified by determining other correlative ecological factors and covering prolonged observation periods.
4

Numerical analysis on rib-tubes of seawater open rack vaporizer with the spoiler lever

81%
Su H., Yu S., Fan J., Wei X.
Polish Maritime Research
|
2017
|
tom 24
|
nr Special Issue S2
In order to explore a more reasonable structure and operating parameter, guide the design and improve the gasification of seawater Open Rack Vaporizer (ORV), Research on the rules of seawater that flows and heat transfer in the ORV tube was studied in this paper. By simplifying the model, heat transfer tube model with spoiler lever was obtained and simulated, the distribution of temperature field, gas ratio, velocity field and press field in rib tube were analyzed, and different inlet velocity of LNG, roughness of the tube wall both effected on the overall gasification, the results shows that the actual gasification efficiency from heat transfer tube is higher than normal, small difference of gas ratio outlet, velocity and temperature are both lower, LNG could be easer gasified at operating temperature between -162°C~+3°C than that between -162°C~+0°C
5

Soil respiration in response to a short-term nitrogen addition in an alpine steppe of Northern Tibet

81%
Sun J., Cheng G., Fan J.
Polish Journal of Ecology
|
2013
|
tom 61
|
nr 4
Northern Tibet has a vital role in global ecological security. This study determined the effect of environmental factors on the soil respiration of an alpine steppe. Short-term nitrogen addition (2 g N m⁻² yr⁻¹) was performed in an alpine steppe in Northern Tibet in June, 2011. Soil respiration was observed during the growing season of 2011 using LI-8100. The results were as follows. First, soil respiration had clear seasonal patterns, and significant differences existed between the control (CK) and nitrogen addition (ND) treatments (P = 0.004). Second, soil respiration was more sensitive to soil temperature (R² = 0.988, ND; R² = 0.05, CK) than soil moisture (R² = 0.0003, ND; R² = 0.038, CK), and the relationship between soil temperature and soil respiration in ND treatment was more significant than that in CK. Third, the relationships between soil chemical properties and root biomass in CK were greater than that in ND plots, especially the relationship of root biomass with the available nitrogen and nitrate nitrogen. These results indicated that differences among geographical conditions resulted in different phenomena of gas emissions, immature soil, and extremely short plant growing time, which may all be remarkably influenced in an alpine steppe.
6

Analysis of sources and concentrations of heavy metal contents in PM10 over a four-season cycle in a heavily industrialised city in China

71%
Jin X., Fan J., Niu H., Ling P., Yu Q.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 5
In order to study the sources and concentrations of heavy metals in atmospheric PM₁₀, a total of 144 samples were collected in two areas of Handan, China. The metal contents of Mn, Co, Ni, Cu, Cd, and Pb in the sample were analysed by inductively coupled plasma mass spectrometry. Contamination characteristics and sources were analysed by the geo-accumulation index and the enrichment factor method. Results indicated that heavy metal elements Mn, Cu, and Pb accounted for 96.9% of the total concentration. In addition, the seasonal levels of concentrations of the six elements from high to low were in the order of winter > fall > spring > summer. In both areas, the metal contents of Cd, Pb, and Cu were at levels 6, 4 and 2, respectively. Co and Ni were not considered polluting elements. The element Cd was mainly from anthropogenic sources, while the element Mn was mainly from natural sources. The enrichment factor values of Cu and Pb were between 10 and 100. The study revealed that pollution by heavy metals in industrialised cities is astounding, and leads to serious consequences for human health. Urgent measures are required to reinforce prevention and control of this pollution.
7

Leaf litter decomposition in three subalpine forests along an elevation gradient in Tibet

71%
Fan J., Zhang X., Lu X., Yan Y., Wang X.
Polish Journal of Environmental Studies
|
2014
|
tom 23
|
nr 4
Litter decomposition is a fundamental ecosystem process, and climate and litter chemistry strongly control rates of litter decay. In this work, three forests along an elevation gradient on the eastern slope of Sergyemla Mountain were selected to compare litter decomposition and chemical fraction loss rates, and further to evaluate the effects of environmental factors and litter chemistry on the litter decomposition process. The leaf litter decomposition coefficient of the mixed conifer and broadleaf forest (MCBF, 3,169 m a.s.l.), sclerophyllous evergreen broadleaf forest (SEBF, 3,453 m a.s.l.), and subalpine dark coniferous forest (SDCF, 3,957 m a.s.l.) sites were 0.04, 0.03, and 0.02 month-1, respectively. The litter mass loss at the MCBF site significantly correlated with litter quality, but that of the SEBF and the SDCF sites did not. In addition, there was a significant positive relationship between the litter mass loss and temperature along the elevation gradients. This study demonstrates that the litter decomposition rate decreases with increasing altitude along the elevation gradient. Climate is the key factor influencing litter decay across environmental gradients, but litter quality also affects decomposition rates in low-elevation forests.
8

Integrated effect of MLSS and SRT on performance of a full-scale modified A2/O process

71%
Fan J., Ye J., Zhang H., Ji B., Ye W.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 4
MLSS and SRT are key parameters in process control. A full-scale modified A2/O process varying with MLSS and SRT was evaluated, and MLSS and SRT effect was distinguished by statistical methods so as to seek early diagnosis and efficient control. Results showed that complete SRT rather than MLSS resulted in considerable effluent SS fluctuation with inert SS accumulation. COD removal was more sensitive to MLSS than SRT. Increasing MLSS until 2,000 mg/L could improve COD, SS, and NH3 removal efficiency, and further increases in MLSS simply enhance stability. MLSS of 2,000 mg/L was also efficient in TP removal. SRT shorter than 30 d was the guarantee for PAOs, while SRT longer than 90 d was equal to complete SRT as TP was removed by assimilation. Prolonged SRT from 30 to 90 days reduced the Yobs from 0.17 to 0.15 g MLSS/g COD. MLSS and SRT had no effect on TN removal. Correlation between MLSS and influent was effective for diagnosing longer SRT. MLSS/RSS could be an indicator for TP removal. The suggested control strategy was SRT-assisted MLSS control.
9

Seasonal variation of anammox and denitrification in sediments of two eutrophic urban lakes

71%
Zhao J., Zhu D., Fan J., Hua Y., Zhou W.
Polish Journal of Environmental Studies
|
2015
|
tom 24
|
nr 6
10
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Crown and root biomass equations for the small trees of Pinus koraiensis under canopy

61%
Wang J., Fan J., Fan X., Zhang C., Wu L., v.Gadow K.
Dendrobiology
|
2013
|
tom 70
Estimation of tree biomass is an essential part of studies on carbon sequestration and cycling in forest ecosystem. Small trees grow in the understory and allometric development is different from that of mature trees. However, less attention has been paidto biomass estimates of small trees, especially in mixedforest where tree competition is intensive. Tree allometric equations at both branch level andat whole tree level were, thus, developed and compared for the small trees of Korean pine (Pinus koraiensis) in a mixedstandin northeastern China. At branch level, the best model for live branch biomass was one which used a combination of branch diameter, branch length, whorl position and relative branch depth. For needle biomass, the best model did not significantly improve the estimate with more variables. At whole tree level, stem diameter at breast height (DBH) was a significant determinant of biomass for different components. Tree height did not significantly improve biomass estimation at all. Tree crown variables provedto be useful for estimating all biomass components except the fine roots. The variable measuring abovegroundcompetition intensity was a significant negative determinant of biomass components except canopy biomass. Comparisons to published equations for the same species growing in Heilongjiang province in northeastern China andin central South Korea, were also presented. Both total aboveground biomass and belowground biomass in our study showed somewhat smaller values for a given diameter than the trees growing in other two places.
11

Assessment of environmental microbial effects of insect-resistant transgenic Populus × euramericana cv. ‘74/76’ based on high-throughput sequencing

61%
Fan J., Dong Y., Yu X., Yao L., Li D., Wang J., Yang M.
Acta Physiologiae Plantarum
|
2020
|
tom 42
|
nr 11
12

A light and electron microscopy study of the yak placentome

61%
Xu T., Liu B., Cui Y., He J., Fan J., Yu S.
Folia Morphologica
|
2019
|
tom 78
|
nr 4
Background and Materials and methods: In order to clarify and reveal the morphological characteristics of yak placentomes, placentomes obtained from 151 to 180 days of pregnant yaks were observed using light microscopy and scanning and transmission electron microscopy. Results: The results indicated that sessile, dome-shaped yak placentomes seemed to have a relatively complex villous-crypt architecture pattern. There was a straight maternal plate beneath the placentome. Plentiful uterine glands and a dense cellular layer were present in the endometrium lamina propria close to the maternal plate. Trophoblast giant cells appeared to have similar ultrastructure features to these in other ruminants, including abundant mitochondria, an extensive array of rough endoplasmic reticulum, advanced Golgi complex and many specific secretory granules. Trophoblast giant cells could also secrete neutral and acid glycoconjugates. Furthermore, numerous glycoconjugates were distributed in the connective zones between mononuclear trophoblast cells and crypt epithelial cells as well as in maternal connective tissues. Mononucleate trophoblast cells, which had abundant microvilli that interdigitated with the corresponding microvilli arising from the crypt epithelial cells, had numerous mitochondria and vesicles, but there were no glycoconjugates. Conclusions: The morphological structures of yak placentomes were similar to those of other bovid genera; however, certain differences were observed. These findings might provide morphological evidence for evolutionary relationships between different bovid genera. (Folia Morphol 2019; 78, 4: 818–826)
13

MCP-1, ICAM-1 and VCAM-1 are present in early aneurysmal dilatation in experimental rats

51%
Fan J., Li X., Zhong L., Tong H., Di J., Liu F., Zhao H.-H., Bai S.-L.
Folia Histochemica et Cytobiologica
|
2010
|
tom 48
|
nr 3
14

Molecular mechanism of resistance to antifolates, a review

51%
Banerjee D., Ercikan-Abali E., Waltham M., Schnieders B., Hochhauser D., Li W. W., Fan J., Gorlick R., Goker E., Bertino J. R.
Acta Biochimica Polonica
|
1995
|
tom 42
|
nr 4
Methotrexate (MTX) is a clinically important antifolate that has been used in combination with other chemotherapeutic agents in the treatment of malignancies including acute lymphocytic leukemia, osteosarcoma, carcinomas of the breast, head and neck, choriocarcinoma and non-Hodgkin's lymphoma. The primary target of MTX is the enzyme dihydrofolate reductase (DHFR) which catalyzes the reduction of folate and 7,8-dihydrofoIate to 5,6,7,8-tetrahydrofolate. Understanding of MTX action has revealed how cells acquire resistance to this drug. The four known mechanisms of MTX resistance are a decrease in the uptake of the drug, a decrease in the retention of the drug due to defective polyglutamylation or an increase in polyglutamate breakdown, an increase in the enzyme activity and a decrease in the binding of MTX to DHFR. The molecular basis for some of these mechanisms has been elucidated in MTX resistant cell lines; in particular the occurrence of gene amplification resulting in increased DHFR and point mutations resulting in altered DHFR with reduced affinity for MTX. Cloning of the human folylpolyglutamate synthase gene and the reduced folate transport gene have been reported recently and should facilitate the identification of the molecular basis of these resistant phenotypes. DHFR protein has been shown to regulate its synthesis by exerting an inhibitory influence on its own translation. Addition of MTX relieves this inhibition thus providing a possible molecular explanation for the rapid rise in DHFR activity noted in some cells after MTX administration. Alterations in genes involved in regulating the cell cycle such as cyclin D1 and the retinoblastoma (Rb) gene have also been shown to influence cellular response to MTX. Overexpression of cyclin D1 in HT1080, a human fibrosarcoma cell line, results in decreased MTX sensitivity. The molecular basis of this observation is under investigation. Abnormalities in the Rb gene may also have profound effects on MTX sensitivity. Rb interacts with the family of transcription factors called E2F reducing transcription of genes that contain E2F binding sites in the promoter regions e.g. DHFR. When Rb is deleted or rendered nonfunctional levels of "free" or unbound E2F are high resulting in enhanced transcription of genes such as DHFR. This results in increased DHFR protein and may lead to MTX resistance. As the knowledge regarding mechanisms of resistance increases newer approaches to circumvent such resistance or to target resistant cells can be undertaken.
15

Isolation and characterization of a C-repeat binding factor (CBF)-like gene in cassava (Manihot esculenta Crantz)

42%
Li R., Ji Y., Fan J., Yang C., Yao Y., Zhou Y., Duan R., Liu J., Fu S., Hu X., Guo J.
Acta Physiologiae Plantarum
|
2014
|
tom 36
|
nr 11
Cassava (Manihot esculenta Crantz) is a tropical and subtropical plant and susceptible to chilling injury. In this research, a C-repeat binding factor (CBF)-like gene (GenBank accession number JQ339740) has been isolated from cassava, and named as MeCBF1. The full-length DNA of MeCBF1 is 1,037 base pair (bp), without intron. The 5' untranslated region is 102 bp, the 3' untranslated region is 239 bp, and the open reading frame is 696 bp encoding 231 amino acids. The deduced amino acid sequence of MeCBF1 contains two CBF conserved motifs of PKK(P/R)AGRxKFxETRHP and DSxWR. The MeCBF1 shows 83 % homology to the CRT/DRE binding factor 1 from Hevea brasiliensis (Accession no. AAY43213.1). However, in cassava, the MeCBF1 target genes showed low similarity to the CBF/DREB regulated genes in Arabidopsis thaliana. Quantitative real-time PCR showed that the MeCBF1 was highly expressed in stems and leaves, and lowly expressed in roots. In addition, the expression of the MeCBF1 quickly responded to low temperature stress (4°C). These results suggest that, the MeCBF1 is functional in cassava. Further studies on the MeCBF1 might be helpful to reveal molecular mechanism of cassava’s high sensitivity to low temperature.
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