• Journal of Environmental Science International
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• v.9 no.4
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• pp.339-343
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• 2000

Activated carbons were prepared from Youngwall coal by steam activation in this study. The feasibility of the Youngwall coal to commercial activated carbon was examined. The variation of pore structures and the development of porosity in activated carbons were investigated by changing activation conditions in batch type apparatus. The values of BET surface area and adsorption capacity of iodine and methylene blue of the resulting activated carbons were obtained as high as 1,000$m^2$m^2$$/g, 900mg/g, 150$m\ell$/g, respectively. Youngwall activated carbon prepared in this study showed much higher pore volume in pore diameter over 10 than that of commercial reference activated carbon(Ningxia Taihua ZJ-15C) produced from China anthracite.

• Geomechanics and Engineering
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• v.15 no.5
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• pp.1039-1046
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• 2018

This paper presents a limit analysis of the series of construction stages of shallow tunneling method by investigating their respective safety factors and failure mechanisms. A case study for one particular cross-section of Beijing Subway Line 7 is undertaken, with a focus on the effects of multiple soil layers and construction sequencing of dual tunnels. Results show that using the step-excavation technique can render a higher safety factor for the excavation of a tunnel compared to the entire cross-section being excavated all at once. The failure mechanisms for each different construction stage are discussed and corresponding key locations are suggested to monitor the safety during tunneling. Simultaneous excavation of dual tunnels in the same cross-section should be expressly avoided considering their potential negative interactions. The normal and shear forces as well as bending moment of the primary lining and locking anchor pipe are found to reach their maximum value at Stage 6, before closure of the primary lining. Designing these struts should consider the effects of different construction stages of shallow tunneling method.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1293-1297
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• 2011

To improve the biological activities of rupestonic acid, 21 new rupestonic acid fatty ester derivatives (2a-2h) and aromatic ester derivatives (2i-2u) were synthesized and preliminarily evaluated for their anti-influenza activity in vitro by the national center for drug screening of China, using the Oseltamivir and Ribavirin as reference drugs. The results showed that 2l ($IC_{50}=0.5{\mu}mol/L$) exhibited potent anti-influenza $A_3$ viral activity among the synthesized compounds and was 10-fold more potent than that of the reference drug Oseltamivir ($IC_{50}=5.1{\mu}mol/L$).

• Journal of Korean Society of Forest Science
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• v.97 no.1
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• pp.95-101
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• 2008

The wind speed reduction capability of forest belt of Caragana Korshinskili Kom in Yanchi, Ningxia province in China is as follows. 1. At the height of 0.5 m, the windbreak effect is 3-Strip (30.22%) > 2-Strip (26.53%) > 1-Strip (16.28%) from 1H (H = Tree Height) to 5H, and the windbreak effect is 2-Strip (16.11%) > 3-Strip (12.79%) > 1-Strip (9.82%) for greater than 7H. Further analysis of 2-Strip and 3-Strip revealed that the wind reduction effect of 2-Strip spread to 44H and 3-Strip spread to 27H. This result implies that 3-Strip is most effective for short distances and 2-Strip is most effective for long distances. 2. At the height of 1.0m, the wind speed was relatively constant and the reduction rate of wind speed had a minimal variation, with the reduction rate of 1-Strip (8.04%), 2-Strip (8.23%), and 3-Strip (7.43%). 3. The sandbreak effect is 2-Strip (55.28%) > 3-Strip (37.13%) > 1-Strip (20.87%). Especially, The rate of sandbreak of 1H (86.06%) of 2-Strip is most effective value in whole data.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3361-3367
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• 2012

Two novel Eu(III) complexes with notable properties have been successfully prepared with hydrazone Schiff base ligands, (E)-2-hydroxy-N'-[(2-hydroxynaphthalen-1-yl)methylene]benzohydrazide (3a) and (E)-4-hydroxy-N'-[(2-hydroxynaphthalen-1-yl)methylene]benzohydrazide (3b). DFT, FMO energy and Mulliken charge distribution studies of the ligands allowed us to hypothesize that their HC=N, > C=O and -OH (naphthyl) groups were involved in coordinating with the $Eu^{3+}$ ion. The eight coordination sites of the $Eu^{3+}$ ion were occupied by the three functional groups of the two ligands (3a or 3b) mentioned above and two water molecules. Similar UV, IR and fluorescence spectra indicated the presence of comparable coordination environments for the $Eu^{3+}$ ion in both complexes. Both the ligands and their complexes exhibited moderate DPPH radical scavenging activity. Moreover, it was found that the Eu(III) complexes exhibited fluorescence properties.

• Journal of applied mathematics & informatics
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• v.27 no.1_2
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• pp.49-58
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• 2009

For $1{\leq}k{\leq}r$, let ${\sigma}$($K_{r,r}$ - ke, n) be the smallest even integer such that every n-term graphic sequence ${\pi}$ = ($d_1$, $d_2$, ..., $d_n$) with term sum ${\sigma}({\pi})$ = $d_1$ + $d_2$ + ${\cdots}$ + $d_n\;{\geq}\;{\sigma}$($K_{r,r}$ - ke, n) has a realization G containing $K_{r,r}$ - ke as a subgraph, where $K_{r,r}$ - ke is the graph obtained from the $r\;{\times}\;r$ complete bipartite graph $K_{r,r}$ by deleting k edges which form a matching. In this paper, we determine ${\sigma}$($K_{r,r}$ - ke, n) for even $r\;({\geq}4)$ and $n{\geq}7r^2+{\frac{1}{2}}r-22$ and for odd r (${\geq}5$) and $n{\geq}7r^2+9r-26$.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.4
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• pp.1579-1602
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• 2020

In the design of production system, buffer capacity allocation is a major step. Through polymorphism analysis of production capacity and production capability, this paper investigates a buffer allocation optimization problem aiming at the multi-stage production line including unreliable machines, which is concerned with maximizing the system theoretical production rate and minimizing the system state entropy for a certain amount of buffers simultaneously. Stochastic process analysis is employed to establish Markov models for repairable modular machines. Considering the complex structure, an improved vector UGF (Universal Generating Function) technique and composition operators are introduced to construct the system model. Then the measures to assess the system's multi-state reliability and structural complexity are given. Based on system theoretical production rate and system state entropy, mathematical model for buffer capacity optimization is built and optimized by a specific genetic algorithm. The feasibility and effectiveness of the proposed method is verified by an application of an engine head production line.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.364-372
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• 2016

Sand tubules, made up of sand grains cemented by microbe-induced calcium carbonate precipitation, have been found in China's Ningxia Province. Sand tubules grow like a tree's roots about 40-60 cm below the surface. The properties of sand tubules and their bacterial community were examined. X-Ray diffraction analysis revealed that the sand tubules were associated with crystalline calcite. Scanning electron microscopy showed that the crystalline solid had a lamellar structure and lacked the presence of cells, suggesting that no bacteria acted as nucleation sites, nor that the crystalline solid was formed by the aggregation of bacteria. Denaturing gradient gel electrophoresis analysis showed 11 of the 12 detectable bands were uncultured bacteria by BLAST analysis in the GenBank database, and the rest were closely related to Paenibacillus sp. (100% identity). By cultivation techniques, the only strain isolated from the sand tubule was suggested to be related to Paenibacillus sp.; no archaea were found. Furthermore, Paenibacillus sp. was demonstrated to induce calcium carbonate precipitation in vitro.

• Journal of Electrical Engineering and Technology
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• v.13 no.2
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• pp.580-590
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• 2018

Active distribution system (ADS) considering distributed generation (DG) and electric vehicle (EV) is an effective way to cut carbon emission and improve system benefits. ADS is an evolving, complex and uncertain system, thus comprehensive model and effective optimization algorithms are needed. Battery swapping station (BSS) for EV service is an essential type of flexible load (FL). This paper establishes ADS planning model considering BSS firstly for the minimization of total cost including feeder investment, operation and maintenance, net loss and carbon tax. Meanwhile, immune binary firefly algorithm (IBFA) is proposed to optimize ADS planning. Firefly algorithm (FA) is a novel intelligent algorithm with simple structure and good convergence. By involving biological immune system into FA, IBFA adjusts antibody population scale to increase diversity and global search capability. To validate proposed algorithm, IBFA is compared with particle swarm optimization (PSO) algorithm on IEEE 39-bus system. The results prove that IBFA performs better than PSO in global search and convergence in ADS planning.

• The Plant Pathology Journal
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• v.36 no.3
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• pp.231-243
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• 2020

Rice blast, caused by Magnaporthe oryzae, is one of the most destructive rice diseases worldwide. The aim of this study was to screen bacterial isolates to efficiently prevent the occurrence of rice blast. A total of 232 bacterial isolates were extracted from nonrhizospheric rice soil and were screened for antifungal activity against M. oryzae using a leaf segment assay. Strains S170 and S9 showed significant antagonistic activity against M. oryzae in vitro and in leaf disk assays, and controlled M. oryzae infection under greenhouse conditions. The results showed that strains S170 and S9 could effectively control rice leaf blast and panicle neck blast after five spray treatments in field. This suggested that the bacterial strains S170 and S9 were valuable and promising for the biocontrol of rice disease caused by M. oryzae. Based on 16S rDNA, and gyrA and gyrB gene sequence analyses, S170 and S9 were identified as Bacillus amyloliquefaciens and B. pumilus, respectively. The research also demonstrated that B. amyloliquefaciens S170 and B. pumilus S9 could colonize rice plants to prevent pathogenic infection and evidently suppressed plant disease caused by 11 other plant pathogenic fungi. This is the first study to demonstrate that B. amyloliquefaciens and B. pumilus isolated from nonrhizospheric rice soil are capable of recolonizing internal rice stem tissues.