ISSN 0253-2778

CN 34-1054/N

2016 Vol. 46, No. 8

Display Method:
Original Paper
A rigidity theorem for submanifolds with parallel mean curvature vector field in Sm(1)×R
ZHOU Jundong
2016, 46(8): 625-628. doi: 10.3969/j.issn.0253-2778.2016.08.001
Submanifolds with parallel mean curvature vector field in Sm(1)×R were studied. By using the moving-frame method and some algebraic inequalities, a rigidity theorem was obtained, which generalizes the result in the relevant literatures.
Some energy properties of Yang-Mills connections
SHI Jixu
2016, 46(8): 629-635. doi: 10.3969/j.issn.0253-2778.2016.08.002
E is a vector bundle over a compact Riemannian manifold M=Mn, n≥4, and A is a Yang-Mills connection with Ln[]2 curvature FA on E. Through a mean value inequality of the density |FA|n[]2, an energy concentrate principle of sequences of solutions that have bounded energy is proved. Unless E is a flat bundle, the energy must be bounded from below by some positive constant.
Global attractivity of multiple species competition Lotka-Volterra system with toxicants effect and feedback controls
FU Jinbo, CHEN Lansun, CHENG Rongfu
2016, 46(8): 636-641. doi: 10.3969/j.issn.0253-2778.2016.08.003
By means of species dynamic theory, a nonautonomous Lotka-Volterra multiple species competition system with toxicants effect and feedback controls was established, and the high order nonlinear function was used in the construction of the feedback control variables. By means of Continuation Theorem based on Gaines and Mawhin coincidence degree theory, Barbalat Lemma and constructing an appropriate Lyapunov function, the sufficient conditions for the uniqueness and global attractivity of positive periodic solutions of the system were obtained.
Nondestructive testing of grating imperfections using grating-based X-ray phase-contrast imaging
ZHANG Can, WANG Shenghao, HAN Huajie, YANG Meng, SHAO Qigang, HU Renfang, GAO Kun, LIU Gang
2016, 46(8): 642-651. doi: 10.3969/j.issn.0253-2778.2016.08.004
We reported the usage of grating-based X-ray phase-contrast imaging in nondestructive testing of grating imperfections. It was found that electroplating flaws could be easily detected by conventional absorption signal, and in particular, we observed that the grating defects resulting from uneven ultraviolet exposure could be clearly discriminated with phase-contrast signal. The experimental results demonstrate that grating-based X-ray phase-contrast imaging, with a conventional low-brilliance X-ray source, a large field of view and a reasonable compact setup, which simultaneously yields phase- and attenuation-contrast signal of the sample, can be ready-to-use in fast nondestructive testing of various imperfections in gratings and other similar photoetching products.
Entangled state representation for mesoscopic persistent current ring and its phase-angular momentum
WU Weifeng, FAN Hongyi
2016, 46(8): 652-656. doi: 10.3969/j.issn.0253-2778.2016.08.005
The entangled state representation was establish,in which the phase operator and the angular momentum operator have been applied, to realize the phase-angular momentum quantization of mesoscopic persistent current ring (MPCR) , and derive its energy spectrum. In addition,it was revealed that the ascending/lowering of angular momentum corresponds to the currents increase/decrease through angular momentum representation for the persistent current ring.
Bimolecular chemical reactions in crowded environments
GAO Jing, LIU Lin, YU Wancheng, LUO Kaifu
2016, 46(8): 657-664. doi: 10.3969/j.issn.0253-2778.2016.08.006
Using two-dimensional Langevin dynamics simulations, we investigate the kinetics of the bimolecular chemical reactions in crowded environments. An important finding is that the dependence of the mean reaction time τ on the area fraction of crowders  relies on the manner of varying . Specifically, When  is increased by adding crowders into the circular domain, a monotonic increase in τ is observed. Moreover, the growth rate of τ becomes much faster once the percolation occurs in the system. As  is tuned by varying the radius of the circular domain R, τ has a minimum as a function of , which is a result of two distinct dynamical regimes, i.e., the crowding-dominated regime and the density-dominated regime. As the size of crowders becomes larger, the reaction process is found to be accelerated. Finally, we show that distributions of the reaction time obey the exponential ones, and the degree of crowding does not alter the distribution pattern.
Preparation of a new lead(Ⅱ)-selective electrode with repair mechanism
YE Jian, LI Xueliang, ZHAO Jianjun, MEI Xuelan, LI Qian
2016, 46(8): 665-670. doi: 10.3969/j.issn.0253-2778.2016.08.007
A novel type PbS hollow nano-sphere bag burried in membrane fractions was designed and manufactured as carrier of lead ions on the PVC membrane ion selective electrode. The response of the electrode was linear relationship to the lead ion with concentration between the range of 1×10-2~1×10-5 mol·L-1 , with the slope of 26 mV/pC and the lower detected limit of 71×10-6 mol·L-1. PVC membrane of about 03 mm thickness was put in the lead ion solution with concentration of 1×10-1~1×10-2, 1×10-3~1×10-5 and 1×10-6 ~1×10-7 mol·L-1 , and the response time was 9~15, 20~45 and 55~70 s respectively. In the 1×10-3 mol·L-1 lead ion solution, the range of pH was 3~7 while electrode potential was stable and the silver ion had a certain interference on electrode.
Joint application of reflection and refraction seismic exploration approach to piedmont buried fault at complex geotectonic conditions
WANG Ran, ZHAO Chengbin
2016, 46(8): 671-679. doi: 10.3969/j.issn.0253-2778.2016.08.008
Seismic reflection and refraction exploration techniques have its advantages and limitations to exploring the piedmont buried fault in front of mountain at that complex segment in geotectonic aspect. So a joint of reflection and refraction seismic exploration approach is applied for this case and make best use of the advantages and bypass the disadvantages to infer the location, nature and preliminary activity of the faults. Here, seismic reflection and refraction are jointed to detect the Qizhou segment of the Xiangfan-Guangji fault belt and yield a high-precision time profile of reflection and velocity profile of refraction. These results illustrate a sequence in the shallow and a variation velocity of whole strata. Therefore, the main rupture location, fault property and activity were characterized to be a fault belt rather than a single fault. So its believed that this joint exploration is not only a universal significance in methodology but also an important data for the evaluation of the fault activity surrounding the civil engineering.
Pollutions source apportionment of Linhuan coal mining subsidence water area from Huaibei Coalfield
REN Mengxi, ZHENG Liugen, CHENG Hua, YU Huaijun
2016, 46(8): 680-688. doi: 10.3969/j.issn.0253-2778.2016.08.009
The analysis and assessment of water quality characteristic are of great significance in the research process of water resource management and pollution control of coal mining subsidence area. Five functional areas (A, B, C, D and E) in subsidence area of the Linhuan industrial park in the Huaibei Coalfield were selected to analyze and evaluate the water pollution characteristic of wet season and dry season in 2014 using comprehensive water quality identification index method. Moreover, principle component analysis was applied to identify pollution sources.The results showed that: ① The dominant pollutants were total nitrogen, total phosphorus and dichromate index, indicating a risk of eutrophication of water; ② The comprehensive water quality identification index of different functional areas showed that E(4.240 9)>D(4.130 9)>C(4.040 9)>B(3.940 9)>A(3.630 9) in wet season, and E(4.330 9)=D(4.330 9)>C(4.020 9)>B(3.920 9)>A(3.620 9) in dry season. ③ The pollution in this study area derived mainly from resident activity, coal, chemical factory, and agriculture. These pollution sources shifted from point sources in wet season to non-point sources in dry season.
Insurance contract design based on the type of risk preference of the insured
LIU Tianzhuo, SHUI Yuan, JIAO Huifang
2016, 46(8): 689-695. doi: 10.3969/j.issn.0253-2778.2016.08.010
Empirical studies as questionnaire and models are combined. Risk preference parameters in prospect theory is used to describe the characteristics of the insured risk preference, insured are divided into three categories. In accordance with the characteristics of the insured risk preference by cluster analysis: loss risk rationality type, sensitive to loss probability type and sensitive to loss value type. Characteristics of the insured risk preference are analyzed based on statistical data analysis. Combined with performance-based insurance contracts, insurance contract framework consist of base premium and incentive premiums has been designed for different types of irrational risk preference insured. As for sensitive to loss probability type insured, they can get incentive premiums by setting deductibles. As for sensitive to loss value type insured, full insurance model change into co-insurance when loss beyond the agreed full insurance range. Finally, this type insurance contract can stimulate disaster prevention efforts from the insured, so as to achieve the objective of reducing the risk and reducing the probability of loss.
Interactive relationship between macro-policy and efficiency of securities market in China
DU Yuneng, DU Min
2016, 46(8): 696-701. doi: 10.3969/j.issn.0253-2778.2016.08.011
Macro-policy of securities market is a kind of important markets information. The utility of this information closely related to the effectiveness of the securities market, and they present an interactive relationship. Starting from the test of the securities market efficiencies, the interactive relationship in market efficiencies and 51 macro-policy information has been sorted by Eviews within 35 days before and after. It is concluded that 5490% of macro policies have significant positive relationship with the effectiveness of the securities market, while 4510% of the macroscopic policy reduce the efficiency of market operation. It means that the efficiency of the securities market in China is in little weak level, and with obvious non-linear features, so the securities market should be further perfected.
Information fusion of accelerometers based on the MEMD and holo-spectrum technology
LIU Dongcai, GUO Jie, SHEN Yuan
2016, 46(8): 702-708. doi: 10.3969/j.issn.0253-2778.2016.08.012
Aiming at the coupling in the multi-channel signals measured by accelerometer, a method based on the multivariate empirical mode decomposition (MEMD) and holo-spectrum technology was put forward. Firstly, the MEMD method adaptively decomposed the multi-channel signals into many intrinsic mode functions(IMFs). Then the working frequency IMFs were selected for holo-spectrum analysis and the two-dimensional holo-spectrum and holo-waterfall-plot were obtained, from which the amplitude and direction of the vibration shape can be reflected visually and the vibration modal characteristics can be better analyzed. Finally this method was applied in the vibration analysis of forklift trucks steering wheel. The result proves the correctness and effectiveness of this method.