Wyniki wyszukiwania - Biblioteka Nauki

1

Investigation of highly sensitive surface plasmon resonance biosensors with Au nanoparticles embedded dielectric film using rigorous coupled wave analysis

100%

Wu B. , Wang Q. K.

Optica Applicata

|

2009

|

tom Vol. 39, nr 1

31--41

EN

The detection performance of conventional surface plasmon resonance (SPR) biosensors is limited by its own mechanism. Recently, novel highly sensitive SPR biosensors with Au nanoparticles enhancement are proposed to detect the interaction of small molecules in low concentrations. In this study, the effect of Au nanoparticles enhancement is firstly calculated by using the Maxwell-Garnett effective medium theory (EMT). Then, the influence of different structural parameters of nanoparticles embedded film on the performance is thoroughly investigated by the rigorous coupled wave analysis (RCWA). Electric field distributions in the nanoparticles embedded film are also given. The results strongly indicate that the sensitivity improvement can be achieved by adding a nanoparticle embedded film with optimal structural parameters. The simulation method of RCWA is also proved to be a powerful tool to optimize nanoparticles embedded film based biosensor.

2

Numerical simulation and experimental study on formation of high concentration of H2 generated by gas explosion.

80%

Lei B. , Wu B. , Zhao Y. , Ashraf M. A.

Polish Maritime Research

|

2016

|

tom S 1

131--137

EN

In coal mine fire rescues, if the abnormal increase of gas concentration occurs, it is the primary thing to analyze the reasons and identify sources of the abnormal forming, which is also the basis of judge the combustion state of fire area and formulate proper fire reliefs. Nowadays, related researches have recognized the methane explosion as the source of high concentration of H2 formation, but there are few studies about the conditions and reaction mechanism of gas explosion generating high concentration of H2.Therefore, this paper uses the chemical kinetic calculation software, ChemKin, and the 20L spherical explosion experimental device to simulate the generating process and formation conditions of H2 in gas explosion. The experimental results show that: the decomposition of water vapor is the main base element reaction (R84) which leads to the generation of H2.The free radical H is the key factor to influence the formation of H2 generated from gas explosion. With the gradual increase of gas explosion concentration, the explosive reaction becomes more incomplete, and then the generating quantity of H2 increases gradually. Experimental results of 20L spherical explosion are consistent with the change trend about simulation results, which verifies the accuracy of simulation analysis. The results of explosion experiments show that when gas concentration is higher than 9%, the incomplete reaction of methane explosion increases which leads to the gradual increase of H2 formation

3

Numerical simulation and experimental study on formation of high concentration of H2 generated by gas explosion

80%

Lei B. , Wu B. , Zhao Y. , Ashraf M. A.

Polish Maritime Research

|

2016

|

tom 23

|

nr Special Issue S1

EN

In coal mine fire rescues, if the abnormal increase of gas concentration occurs, it is the primary thing to analyze the reasons and identify sources of the abnormal forming, which is also the basis of judge the combustion state of fire area and formulate proper fire reliefs. Nowadays, related researches have recognized the methane explosion as the source of high concentration of H2 formation, but there are few studies about the conditions and reaction mechanism of gas explosion generating high concentration of H2.Therefore, this paper uses the chemical kinetic calculation software, ChemKin, and the 20L spherical explosion experimental device to simulate the generating process and formation conditions of H2 in gas explosion. The experimental results show that: the decomposition of water vapor is the main base element reaction (R84) which leads to the generation of H2.The free radical H is the key factor to influence the formation of H2 generated from gas explosion. With the gradual increase of gas explosion concentration, the explosive reaction becomes more incomplete, and then the generating quantity of H2 increases gradually. Experimental results of 20L spherical explosion are consistent with the change trend about simulation results, which verifies the accuracy of simulation analysis. The results of explosion experiments show that when gas concentration is higher than 9%, the incomplete reaction of methane explosion increases which leads to the gradual increase of H2 formation

4

Use of fuzzy fault tree analysis and noisy-OR gate bayesian network for navigational risk assessment in Qingzhou Port

80%

Zhao C. , Wu B. , Yip T. L. , Lv J.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

|

2021

|

tom Vol. 15 No. 4

765--771

EN

Collisions and groundings account for more than 80% among all types of maritime accidents, and risk assessment is an essential step in the formal safety assessment. This paper proposes a method based on fuzzy fault tree analysis and Noisy-OR gate Bayesian network for navigational risk assessment. First, a fault tree model was established with historical data, and the probability of basic events is calculated using fuzzy sets. Then, the Noisy-OR gate is utilized to determine the conditional probability of related nodes and obtain the probability distribution of the consequences in the Bayesian network. Finally, this proposed method is applied to Qinzhou Port. From sensitivity analysis, several predominant influencing factors are identified, including navigational area, ship type and time of the day. The results indicate that the consequence is sensitive to the position where the accidents occurred. Consequently, this paper provides a practical and reasonable method for risk assessment for navigational accidents.

5

GAP/DNTF Based PBX Explosives: a Novel Formula Used in Small Sized Explosive Circuits

80%

An C. , Wen X. , Wang J. , Wu B.

Central European Journal of Energetic Materials

|

2016

|

tom Vol. 13, no. 2

397--410

EN

With 3,4-dinitrofurazanofuroxan (DNTF) and glycidyl azide polymer (GAP) as the main explosive and binder respectively, GAP/DNTF based PBX explosives were designed, prepared and used to fill the small groove of some explosive circuits. The formulation was: DNTF 85 wt.%, GAP 11 wt.%, 2,4-toluene diisocyanate (TDI) and other additives making up the final 4 wt.%. After the uncured slurry mixture was prepared by uniform mixing, a squeezing device was used to charge the circuit groove (dimensions less than 1 mm × 1 mm). Scanning electron microscope (SEM) results showed a fine charging effect. Differential Scanning Calorimetry (DSC) was used to determine the energy of activation (Ea) and the pre-factor (A) of GAP/DNTF and these were compared with those for raw DNTF. The influences and causes of it have been investigated. The experimental results for propagation reliability showed that when the dimensions of the linear groove were 0.8 mm × 0.8 mm, 0.7 mm × 0.7 mm, 0.6 mm × 0.6 mm or 0.5 mm × 0.5 mm, GAP/DNTF based PBX explosives can propagate explosion successfully. Furthermore, the H50 and friction sensitivity of GAP/DNTF based PBX explosives were obtained using the following mechanical sensitivity experiments. These properties are vital if GAP/DNTF based PBX explosives are to be applied in complex explosive circuits.

6

Emergency management of maritime accidents in the yangtze river: problems, practice and prospects

80%

Yan X. P. , Wu B. , Zhang D. , Zhang J. F.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

|

2017

|

tom Vol. 11, no. 1

111--118

EN

Maritime accidents have received considerable attentions due to the enormous property damage, casualties and serious environmental pollution. This paper first makes statistical analysis of the different types of maritime accidents in the period of 2012 to 2014 in the Yangtze River. Second, the problems of emergency management of maritime accidents are also proposed from the analysis of the major accident “Eastern Star”.. Afterwards, four practice cases, including decision support for maritime accidents, emergency resource allocation, emergency simulation system and effectiveness of emergency management, are introduced to present the insights gained from these practices. Last, in order to address these problems, this paper proposes that an artificial societies, Computational experiments, and Parallel execution (ACP) approach should be introduced to establish an improved management system for maritime accidents in the future, and an ACP based maritime accident emergency management framework is proposed.

7

Stability analysis of high-order Hopfield-type neural networks based on a new impulsive differential inequality

71%

Liu Y. , Yang R. , Lu J. , Wu B. , Cai X.

International Journal of Applied Mathematics and Computer Science

|

2013

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tom Vol. 23, no. 1

201--211

EN

This paper is devoted to studying the globally exponential stability of impulsive high-order Hopfield-type neural networks with time-varying delays. In the process of impulsive effect, nonlinear and delayed factors are simultaneously considered. A new impulsive differential inequality is derived based on the Lyapunov–Razumikhin method and some novel stability criteria are then given. These conditions, ensuring the global exponential stability, are simpler and less conservative than some of the previous results. Finally, two numerical examples are given to illustrate the advantages of the obtained results.

8

Changes in soil organic carbon and its density fractions after shrub-planting for desertification control

71%

Liu J.-B. , Zhang Y.-Q. , Wu B. , Qin S.-G. , Lai Z.-R.

Polish Journal of Ecology

|

2014

|

tom Vol. 62, nr 2

205--216

EN

Planting shrubs on sand land and degraded pasture are two main measures for desertification control particularly in northwest China. However, their effects on soil organic carbon (SOC) and its fractions remain uncertain. We assessed the changes in stocks of SOC, light fraction of SOC (LF–SOC) and heavy fraction of SOC (HF–SOC) after planting Artemisia ordosica (AO, 17 years), Astragalus mongolicum (AM, 5 years) and Salix psammophila (SP, 16 years) in sand land and planting Caragana microphylla (CM, 24 years) on degraded pasture. Results show that: 1) after planting AO, AM and SP on sand land, SOC stocks increased by 162.5%, 45.2% and 70.8%, respectively, and LF–SOC accounted for a large proportion in the increased SOC. Dry weights of LF–SOC, rather than carbon concentrations, were higher in shrublands than that in sand land; 2) after planting CM on degraded pasture, SOC stock decreased by 9.3% and all the loss was HF–SOC in 60–100 cm soil layer where both herbaceous fine root biomass (HFRB) and soil water content (SWC) also decreased. The results indicate that planting shrubs can result in an increase of SOC in sand land, whereas that can lead to a decrease of SOC in degraded pasture. The increase of SOC in sand land mainly bases on the accumulation of dry weight of LF–SOC. The loss of SOC in degraded pasture is caused by the decrease of carbon concentrations of HF–SOC, which can be related to the reduction of HFRB and SWC in deep soil layer. Therefore, shrub-planting for desertification control not always improve the quantity and stability of SOC in northwest China.

9

An Insensitive Booster Explosive: DAAF Surface-coated with Viton A

71%

Li X. , Wu B. , Liu S. , An C. , Wang J.

Central European Journal of Energetic Materials

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2018

|

tom Vol. 15, no. 3

445--455

EN

3,3’-Diamino-4,4’-azoxyfurazan (DAAF) is the principal component of an insensitive booster explosive; refined DAAF and DAAF surface-coated with Viton A were prepared. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) were employed to characterize the morphology, composition, and thermal decomposition of these samples. The impact sensitivity and theoretical detonation velocity of DAAF-based composites were also measured and analyzed. The results showed that DAAF surface-coated with Viton A was successfully obtained, and the impact sensitivity of DAAF/Viton A composites was much lower than that of crude DAAF. In addition, DAAF/Viton A composites exhibited better thermal stability compared to crude DAAF and refined DAAF. The theoretical detonation velocity of DAAF/Viton A composites and TATB/Viton A composites are roughly the same. Therefore, there is still great potential for DAAF to be used as the main explosive component of a booster explosive.

10

Physiological factors for tolerance of Kosteletzkya virginica (L.) Presl to one-instar bollworms of Helicoverpa armigera (Hubner)

71%

Zhou J. , Zhou Jr. J. , Wu B. , Qin P. , Qi A.

Acta Physiologiae Plantarum

|

2010

|

tom 32

|

nr 3

EN

An experiment was designed to investigate the tolerance and response of the Kosteletzkya virginica (L.) Presl to one-instar bollworms of Helicoverpa armigera (Hubner). In this experiment, the insects obviously brought an enhancement in damaged rate of leaf area (DRLA), average diameter of bitten hole (ADBH) and average grade of leaf damage (AGLD) in K. virginica seedlings. When amount of insect increased to 4 per top leaf, the average DRLA, AABH, ADBH and AGLD were 8.6%, 9.2 mm, 2.7 mm and 2.0 mm, respectively, and the seedlings showed a potential insect-tolerance to this insect stress. Furthermore, with an increase of insect density, MDA, relative permeability of membrane (RPM), O₂⁻ production and soluble sugar concentration all enhanced, whereas activities of SOD and POD increased and subsequently declined. By statistical analysis, it was drawn that biotoxicity of O₂⁻ was the first destroying factor, cell membrane decomposition ranked the second, and the destruction of membrane lipid peroxidation was the slightest to K. virginica seedlings. Moreover, under the insect stress, POD was the most significant factor in protecting the seedlings, soluble sugar acted as the subordinate one, and the protection of SOD was the slightest compared to two others. In addition, insect stress obviously affected chlorophyll-fluorescence characteristics, and resulted in a significant increase in Fo and qN, and a significant reduction in Fv/Fm, ETR and qP during experiment.

11

Changes in soil organic carbon and its density fractions after shrub-planting for desertification control

71%

Liu J.-B. , Zhang Y.-Q. , Wu B. , Qin S.-G. , Lai Z.-R.

Polish Journal of Ecology

|

2014

|

tom 62

|

nr 2

EN

Planting shrubs on sand land and degraded pasture are two main measures for desertification control particularly in northwest China. However, their effects on soil organic carbon (SOC) and its fractions remain uncertain. We assessed the changes in stocks of SOC, light fraction of SOC (LF–SOC) and heavy fraction of SOC (HF–SOC) after planting Artemisia ordosica (AO, 17 years), Astragalus mongolicum (AM, 5 years) and Salix psammophila (SP, 16 years) in sand land and planting Caragana microphylla (CM, 24 years) on degraded pasture. Results show that: 1) after planting AO, AM and SP on sand land, SOC stocks increased by 162.5%, 45.2% and 70.8%, respectively, and LF–SOC accounted for a large proportion in the increased SOC. Dry weights of LF–SOC, rather than carbon concentrations, were higher in shrublands than that in sand land; 2) after planting CM on degraded pasture, SOC stock decreased by 9.3% and all the loss was HF–SOC in 60–100 cm soil layer where both herbaceous fine root biomass (HFRB) and soil water content (SWC) also decreased. The results indicate that planting shrubs can result in an increase of SOC in sand land, whereas that can lead to a decrease of SOC in degraded pasture. The increase of SOC in sand land mainly bases on the accumulation of dry weight of LF–SOC. The loss of SOC in degraded pasture is caused by the decrease of carbon concentrations of HF–SOC, which can be related to the reduction of HFRB and SWC in deep soil layer. Therefore, shrub-planting for desertification control not always improve the quantity and stability of SOC in northwest China.

12

Exogenous gibberellic acid increases the fruit weight of ‘Comte de Paris’ pineapple by enlarging flesh cells without negative effects on fruit quality

61%

Li Y. H. , Wu Y. J. , Wu B. , Zou M. H. , Zhang Z. , Sun G. M.

Acta Physiologiae Plantarum

|

2011

|

tom 33

|

nr 5

EN

In mainland China, the most popular pineapple cultivar is ‘Comte de Paris’. Gibberellic acids have been widely applied to enhance fruit growth in various species. To evaluate the effect of gibberellic acid (GA₃) on ‘Comte de Paris’ pineapple production and quality, pineapple fruits were sprayed with GA₃ at concentrations of 5, 20, 50, or 100 mg 1⁻¹ at both 0 and 15 days after flowering (DAF). Fruits were sampled every 15 days from 0 to 60 DAF (maturation) for flow cytometric analysis and histological observation. The results showed that the treatments with the three highest concentrations of GA₃ significantly increased fruit weight, and the most effective concentration was 50 mg 1⁻¹ GA₃, which increased the flesh weight by 20.3% compared to the control. Although treatment with GA₃ had little effect on the total soluble solids and fruit juice pH, it increased the vitamin C content. Although flow cytometric analysis showed that the 50 mg 1⁻¹ GA₃ treatment had only a slight impact on the number of S phase cells, histological observations indicated that the increase of fruit volume and flesh weight under this GA₃ treatment was not due to the increase of cell number but a result of the increase of cell area in the fruit flesh.

13

Identification for soybean host factors interacting with P3N-PIPO protein of Soybean mosaic virus

61%

Song P. , Chen X. , Wu B. , Gao L. , Zhi H. , Cui X.

Acta Physiologiae Plantarum

|

2016

|

tom 38

|

nr 06

14

Characterization of grain protein content gene (GPC-B1) introgression lines and its potential use in breeding for enhanced grain zinc and iron concentration in spring wheat

61%

Velu G. , Singh R. P. , Cardenas M. E. , Wu B. , Guzman C. , Ortiz-Monasterio I.

Acta Physiologiae Plantarum

|

2017

|

tom 39

|

nr 09

15

Considering the composite tree attributes extracted by UAV can improve the accuracy of street tree species classification

61%

Tang H. , Miao F. , Yang J. , Wu B. , Zhang Q. , Hao H.

Dendrobiology

|

2024

|

tom 91

16

Drought enhanced the allelopathy of goldenrod on the seed germination and seedling growth performance of lettuce

61%

Wu R. , Wu B. , Cheng H. , Wang S. , Wei M. , Wang C.

Polish Journal of Environmental Studies

|

2021

|

tom 30

|

nr 1

17

Surface plasmon resonance sensor based on photonic crystal fiber filled with silver nanowires

61%

Fu X. , Lu Y. , Huang X. , Hao C. , Wu B. , Yao J.

Optica Applicata

|

2011

|

tom Vol. 41, nr 4

941--951

EN

Silver nanowire filled photonic crystal fibers are proposed in this paper to achieve surface plasmon resonance sensors and overcome the complicacy and difficulty of coating the holes in the photonic crystal fiber. Optical field distributions of these fibers at different wavelengths are calculated and simulated using the finite element method (FEM), and the sensing properties are discussed in both areas of resonant wavelength and intensity detection. Numerical simulation results show that carefully designed structure of the sensor brings about an excellent effect, with both spectral and intensity sensitivity in the range of 4×10-5-5×10-5 RIU, better than in the case of similar structures coated with metal film, and the fabrication is expected to be simplified.

18

The Effect of Mixed Support of Carbon Black and Nanographite on Catalytic Activity of Pt Catalysts for Methanol Electrooxidation

61%

Teng Z. , Wu B. , Wang Y. , Tang Y. , Lu T. , Gao Y.

Polish Journal of Chemistry

|

2008

|

tom Vol. 82, nr 11

2197-2206

EN

The effect of mixed support of carbon black and nanographite (CG) on electrocatalytic activity and stability of the supported Pt catalyst for the methanol oxidation was investigated. It was found that the electrocatalytic activity and stability of the supported Pt catalyst for the methanol oxidation depended on the mass ratio of carbon black and nanographite. When the mass ratio was 10:1, the electrocatalytic activity and stability of the CG supported Pt (Pt/CG) catalyst for the methanol oxidation was the best.

19

Synthesis, Crystal Structure, and Properties of a Novel, Highly Sensitive Energetic, Coordination Compound: Iron (II) Carbohydrazide Perchlorate

61%

Liu R. , Zhou Z. , Qi S. , Yang L. , Wu B. , Huang H. , Zhang T.

Central European Journal of Energetic Materials

|

2013

|

tom Vol. 10, no. 1

17--36

EN

A single crystal of iron (II) carbohydrazide perchlorate [FeII (CHZ)3](ClO4)2 (FeCP), a novel, lead-free, energetic coordination compound, was synthesized and its structure determined by X-ray single crystal diffraction for the frst time. The crystal belongs to the monoclinic system P2(1)/n space group, with a = 1.0066(2) nm, b = 0.8458(2) nm, c = 2.1194(4) nm, β = 100.693(3)° and Z = 4. The central Fe(II) ion is coordinated to three bidentate carbohydrazide units through the carbonyl oxygen atom and an amino nitrogen atom, forming a six-coordinated, non-centrosymmetric complex cation. The thermal analyses by differential scanning calorimetry and thermogravimetry show that the onset temperature of thermal decomposition (152.7 °C) and the critical temperature of thermal explosion of FeCP (161.2 °C) are both much lower than those of other transition metal carbohydrazide perchlorate compounds, and also those of some other primary explosives in service. FeCP has a high enthalpy of combustion, as measured by oxygen bomb calorimetry. The impact, friction and fame sensitivity tests indicate that FeCP is extremely sensitive and hazardous. Unexpected explosions occurred even during the operational processes. In order to explore the intrinsic cause of these explosions, theoretical calculations of the orbital energies were performed based on DTF. These results reveal that the impact sensitivity is positively correlated with the energy gap between HOMO and LUMO: the smaller energy gap results in the higher impact sensitivity.

20

Characterization of Soil Particle Size Distribution with a Fractal Model in the Desertified Regions of Northern China

51%

Gao G.-L. , Ding G.-D. , Zhao Y.-Y. , Wu B. , Zhang Y.-Q. , Guo J.-B. , Qin S.-G. , Bao Y.-F. , Yu M.-H. , Liu Y.-D.

Acta Geophysica

|

2016

|

tom Vol. 64, no. 1

1--14

EN

We constructed an aeolian soil database across arid, semi-arid, and dry sub-humid regions, China. Soil particle size distribution was measured with a laser diffraction technique, and fractal dimensions were calculated. The results showed that: (i) the predominant soil particle size distributed in fine and medium sand classifications, and fractal dimensions covered a wide range from 2.0810 to 2.6351; (ii) through logarithmic transformations, fractal dimensions were significantly positive correlated with clay and silt contents (R2 = 0.81 and 0.59, P < 0.01), and significantly negative correlated with sand content (R2 = 0.50, P < 0.01); (3) hierarchical cluster analysis divided the plots into three types which were similar to sand dune types indicating desertification degree. In a large spatial scale, fractal dimensions are still sensitive to wind-induced desertification. Therefore, we highly recommend that fractal dimension be used as a reliable and quantitative parameter to monitor soil environment changes in desertified regions. This improved information provides a firm basis for better understanding of desertification processes.