In this paper, a carangiform robotic fish with 4-DoF (degree of freedom) tail has been developed. The robotic fish has capability of swimming under two modes that are radio control and autonomous swimming. Experimen...In this paper, a carangiform robotic fish with 4-DoF (degree of freedom) tail has been developed. The robotic fish has capability of swimming under two modes that are radio control and autonomous swimming. Experiments were conducted to investigate the influences of characteristic parameters including the frequency, the amplitude, the wave length, the phase difference and the coefficient on forward velocity. The experimental results shown that the swimming performance of the robotic fish is affected mostly by the characteristic parameters observed.展开更多
In this paper, the numeral response and main parameters of experimental population life table were analyzed for determining the suppressing ability of Amblyseius cucumeris on Panonychus citri. The result showed that: ...In this paper, the numeral response and main parameters of experimental population life table were analyzed for determining the suppressing ability of Amblyseius cucumeris on Panonychus citri. The result showed that: (1) Under 21-31°C and 1 - 9 prey densities/leaf fragment condition, the prey consumptions of A. cucumeris increased with the temperature or prey density; (2) In 1:3 predator-prey ratio treatment, the suppression of P. citri (Ro=34.0053; T=19.4369; t=3.8204) was rather weak, it was enhanced as the ratio over 5:30, and the populations of P. citri in these treatments can be fully controlled within 4-5 days; (3) Under 25±1°C, 80-85% RH and 15L: 9D illumination conditions, the net reproductive rate, mean generation duration and the time for population double increase of P. citri (Ro=34.0053; T=19.4369; t=3.8204) were higher than those of A. cucumeris (Ro=21.8750; T=16.8943; t=3.7954). While the intrinsic rate of increase and finite rate of increase of the former (rm=0.1814; λ=1.1989) were lower than those of the latter (rm=0.1826; λ=1.2004). These results indicated that A. cucumeris is a desirable bio-control agent to suppress P. citri at lower population stage in citrus orchard.展开更多
Electrospinning is a highly versatile technique to prepare continuous fibers with diameters of the order of nanometers. The remarkable high aspect ratio and high porosity bring electrospun nanofibers highly attractive...Electrospinning is a highly versatile technique to prepare continuous fibers with diameters of the order of nanometers. The remarkable high aspect ratio and high porosity bring electrospun nanofibers highly attractive to various nanotechnological applications such as filtration membranes, protective clothing, drug delivery, tissue-engineering, biosensors, catalysis, fuel cells and so on. In this review, we collectively summarized the recent progress in developments of the electrospun ultrafine polyamide-6 based nanofibers preparation,characterization and their applications. Information of this polyamide-6 and composites together with their processing conditions for electrospinning of ultrafine nanofibers has been summarized in this review. The recent developments made during last few years on these materials are addressed in this review. We are anticipating that this review certainly drive the researchers for developing more intensive investigation for exploring in many technological areas.展开更多
Microwave remote sensing has become the primary means for sea-ice research, and has been supported by a great deal of field experiments and theoretical studies regarding sea-ice microwave scattering. However, these st...Microwave remote sensing has become the primary means for sea-ice research, and has been supported by a great deal of field experiments and theoretical studies regarding sea-ice microwave scattering. However, these studies have been barely carried in the Bohai Sea. The sea-ice microwave scattering mechanism was first developed for the thin sea ice with slight roughness in the Bohai Sea in the winter of 2012, and included the backscattering coefficients which were measured on the different conditions of three bands(L, C and X), two polarizations(HH and VV), and incident angles of 20° to 60°, using a ground-based scatterometer and the synchronous physical parameters of the sea-ice temperature, density, thickness, salinity, and so on. The theoretical model of the sea-ice electromagnetic scattering is obtained based on these physical parameters. The research regarding the sea-ice microwave scattering mechanism is carried out through two means, which includes the comparison between the field microwave scattering data and the simulation results of the theoretical model, as well as the feature analysis of the four components of the sea-ice electromagnetic scattering. It is revealed that the sea-ice microwave scattering data and the theoretical simulation results vary in the same trend with the incident angles. Also, there is a visible variant in the sensitivity of every component to the different bands.For example, the C and X bands are sensitive to the top surface, the X band is sensitive to the scatterers, and the L and C bands are sensitive to the bottom surface, and so on. It is suggested that the features of the sea-ice surfaces and scatterers can be retrieved by the further research in the future. This experiment can provide an experimental and theoretical foundation for research regarding the sea-ice microwave scattering characteristics in the Bohai Sea.展开更多
In the experimental rabbit arteriosclerosis, the change of the cerebrovascular hemodynamic parameters (CVHP) and the effect of Chuanxiong (CX) on CVHP were observed. In arteriosclerosis group (AS group), the mean flow...In the experimental rabbit arteriosclerosis, the change of the cerebrovascular hemodynamic parameters (CVHP) and the effect of Chuanxiong (CX) on CVHP were observed. In arteriosclerosis group (AS group), the mean flow (Qmean), mean velocity (Vmean), maximal velocity (V max) and minimal velocity (Vmin) of the carotid blood flow and cerebrovascular compliance for zero pressure (CO) were significantly decreased (P < 0.05, 0.01), but the values of cerebrovascular peripheral resistance (R) and characteristic impedance (Zc) were significantly increased (P<0.05 and 0.01), and the value of R showed significant positive correlation with the extent of carotid lesions (P < 0.01). All indexes of CVHP of the Chuanxiong group (CX group) were close to and had no significant difference from those of the normal group (N group) but Qmean, Vmean, Vmin, CO and R were significantly better than those of the AS group (P<0.05, 0.01). These results showed that CX can effectively improve cerebrovascular hemodynamics.展开更多
Dust emission generated by wind erosion is a basic process before the transport and deposition of dust particles. Parameterization of dust emission flux is important for accurate simulation and prediction of dust even...Dust emission generated by wind erosion is a basic process before the transport and deposition of dust particles. Parameterization of dust emission flux is important for accurate simulation and prediction of dust events. Field observation and numerical simulation are two approaches to understand the complex process of dust emission. Great progress has been made on the characteristics and mechanism of dust emission during dust storm events. This review introduces the major factors influencing dust emission and summarizes the calculation methods of several key parameters of dust emission, including the threshold friction velocity u.t, threshold wind speed Ut, streamwise saltation flux Q, and (vertical) dust emission flux F, from perspectives of both observation and parameterization. The paper also discusses the improvement, application, and validation of different dust emission schemes in dust models. Existing problems and future research directions are elaborated as well.展开更多
文摘In this paper, a carangiform robotic fish with 4-DoF (degree of freedom) tail has been developed. The robotic fish has capability of swimming under two modes that are radio control and autonomous swimming. Experiments were conducted to investigate the influences of characteristic parameters including the frequency, the amplitude, the wave length, the phase difference and the coefficient on forward velocity. The experimental results shown that the swimming performance of the robotic fish is affected mostly by the characteristic parameters observed.
文摘In this paper, the numeral response and main parameters of experimental population life table were analyzed for determining the suppressing ability of Amblyseius cucumeris on Panonychus citri. The result showed that: (1) Under 21-31°C and 1 - 9 prey densities/leaf fragment condition, the prey consumptions of A. cucumeris increased with the temperature or prey density; (2) In 1:3 predator-prey ratio treatment, the suppression of P. citri (Ro=34.0053; T=19.4369; t=3.8204) was rather weak, it was enhanced as the ratio over 5:30, and the populations of P. citri in these treatments can be fully controlled within 4-5 days; (3) Under 25±1°C, 80-85% RH and 15L: 9D illumination conditions, the net reproductive rate, mean generation duration and the time for population double increase of P. citri (Ro=34.0053; T=19.4369; t=3.8204) were higher than those of A. cucumeris (Ro=21.8750; T=16.8943; t=3.7954). While the intrinsic rate of increase and finite rate of increase of the former (rm=0.1814; λ=1.1989) were lower than those of the latter (rm=0.1826; λ=1.2004). These results indicated that A. cucumeris is a desirable bio-control agent to suppress P. citri at lower population stage in citrus orchard.
基金financially supported by the Ministry of Education, Science Technology (MEST) and National Research Foundation of Korea (NRF) through the Human Resource Training Project for Regional Innovation(2012H1B8A2025931)supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST)(No.2012R1A2A2A01046086)
文摘Electrospinning is a highly versatile technique to prepare continuous fibers with diameters of the order of nanometers. The remarkable high aspect ratio and high porosity bring electrospun nanofibers highly attractive to various nanotechnological applications such as filtration membranes, protective clothing, drug delivery, tissue-engineering, biosensors, catalysis, fuel cells and so on. In this review, we collectively summarized the recent progress in developments of the electrospun ultrafine polyamide-6 based nanofibers preparation,characterization and their applications. Information of this polyamide-6 and composites together with their processing conditions for electrospinning of ultrafine nanofibers has been summarized in this review. The recent developments made during last few years on these materials are addressed in this review. We are anticipating that this review certainly drive the researchers for developing more intensive investigation for exploring in many technological areas.
基金The National Science Foundation for Young Scientists of China under contract No.41306193the National Special Research Fund for Non-Profit Marine Sector under of China under contract No.201105016the European Space Agency-Ministry of Science and Technology of the People’s Republic of China(ESA-MOST)Dragon 3 Cooperation Programme under contract No.10501
文摘Microwave remote sensing has become the primary means for sea-ice research, and has been supported by a great deal of field experiments and theoretical studies regarding sea-ice microwave scattering. However, these studies have been barely carried in the Bohai Sea. The sea-ice microwave scattering mechanism was first developed for the thin sea ice with slight roughness in the Bohai Sea in the winter of 2012, and included the backscattering coefficients which were measured on the different conditions of three bands(L, C and X), two polarizations(HH and VV), and incident angles of 20° to 60°, using a ground-based scatterometer and the synchronous physical parameters of the sea-ice temperature, density, thickness, salinity, and so on. The theoretical model of the sea-ice electromagnetic scattering is obtained based on these physical parameters. The research regarding the sea-ice microwave scattering mechanism is carried out through two means, which includes the comparison between the field microwave scattering data and the simulation results of the theoretical model, as well as the feature analysis of the four components of the sea-ice electromagnetic scattering. It is revealed that the sea-ice microwave scattering data and the theoretical simulation results vary in the same trend with the incident angles. Also, there is a visible variant in the sensitivity of every component to the different bands.For example, the C and X bands are sensitive to the top surface, the X band is sensitive to the scatterers, and the L and C bands are sensitive to the bottom surface, and so on. It is suggested that the features of the sea-ice surfaces and scatterers can be retrieved by the further research in the future. This experiment can provide an experimental and theoretical foundation for research regarding the sea-ice microwave scattering characteristics in the Bohai Sea.
文摘In the experimental rabbit arteriosclerosis, the change of the cerebrovascular hemodynamic parameters (CVHP) and the effect of Chuanxiong (CX) on CVHP were observed. In arteriosclerosis group (AS group), the mean flow (Qmean), mean velocity (Vmean), maximal velocity (V max) and minimal velocity (Vmin) of the carotid blood flow and cerebrovascular compliance for zero pressure (CO) were significantly decreased (P < 0.05, 0.01), but the values of cerebrovascular peripheral resistance (R) and characteristic impedance (Zc) were significantly increased (P<0.05 and 0.01), and the value of R showed significant positive correlation with the extent of carotid lesions (P < 0.01). All indexes of CVHP of the Chuanxiong group (CX group) were close to and had no significant difference from those of the normal group (N group) but Qmean, Vmean, Vmin, CO and R were significantly better than those of the AS group (P<0.05, 0.01). These results showed that CX can effectively improve cerebrovascular hemodynamics.
基金Supported by the National(Key)Basic Research and Development(973)Program of China(2010CB428501)China Meteorological Administration Special Public Welfare Research Fund(GYHY201006014)+1 种基金National Natural Science Foundation of China(41075005 and 41475007)Research Fund for the Doctoral Program of Higher Education of Ministry of Education of China(20110001130010)
文摘Dust emission generated by wind erosion is a basic process before the transport and deposition of dust particles. Parameterization of dust emission flux is important for accurate simulation and prediction of dust events. Field observation and numerical simulation are two approaches to understand the complex process of dust emission. Great progress has been made on the characteristics and mechanism of dust emission during dust storm events. This review introduces the major factors influencing dust emission and summarizes the calculation methods of several key parameters of dust emission, including the threshold friction velocity u.t, threshold wind speed Ut, streamwise saltation flux Q, and (vertical) dust emission flux F, from perspectives of both observation and parameterization. The paper also discusses the improvement, application, and validation of different dust emission schemes in dust models. Existing problems and future research directions are elaborated as well.