卷弧翼气动特性研究进展

本文列举了卷弧翼在战术武器中的应用实例，介绍了卷弧翼的几何特性、气动特性、优缺点及布局设计，评述了对卷弧翼气动特性所做的理论与试验研究工作。最后指出了有待进一步研究的问题。

Design of Metering Device Key Parts of Pneumatic Grass Seeder

Based on the mechanical and physical properties study of forage grass seeds, multi-line with one-device type metering device was designed. It was composed of adjustable screw, stirrer, metering device housing and central metering sheave and so on. The sowing rate can be set by turning the screw to change the working length of the central metering sheave relative to the metering device housing. The stirrer inside of the sheave housing is used to prevent seeds overhead. And metering of different sizes of seed is adjusted by changing the position of internal components of the slot wheel mechanism. Innovative design on the structure of the central metering sheave was finished. According to the structure parameters and physical characteristic parameters, different seed sowing rate of per hectares was calculated. And then the working length scale of the central metering groove wheel was made. And there is a one-to-one correspondence between scale values and sowing quantity per hectare of different kinds of seed.

Self-magnetism and Persistent Photoconductivity

Persistent photoconductivity has been investigated by various models, among which the Macroscopic Barrier model, Large-Lattice-Relaxation model, and Random Local Potential Fluctuations model are mostly well known. Although the three well-known models have played important roles in describing the persistent photoconductivity, they are not the principal cause of persistent photoconductivity. In this paper a classical model originated from ＂selfmagnetism of electron gas＂ is proposed to illustrate the persistent photoconductivity phenomenon. This classical model is based on electron gas pulsation, which depends on the charge density. Different concentrations of current carriers create different frequencies in the system, and thus the system is sensitive to different wave lengths of incident light. Then the construction of different detectors can be possible for different wave lengths of incident light.

Solution of Modern Thermo Physical Problems of Applied External and Internal Aerodynamics with Dark Matter-Energy Simulation

The paper is devoted to new, experimentally registered thermo physical problems of high temperature applied external and internal aerodynamics which is defined first of all by intensive interaction of the gaseous media and thermal radiation. The first report section analyses basic complexities of designing high temperature air breathing engines related to origin of so-called ＂unexpected＂ heat of working process. The next parts of the report consider physical, chemical and plasma features of aerodynamics of reentry space blunt bodies and meteors with specified account of thermal radiation influence. Our solutions are based on the classical Dark Matter-Energy simulation. We present special experimental data for Dark Matter pressure registration on the earth conditions.

Establishment of animal models for chronic pulmonary embolism

Objective： To establish the animal model for the chronic pulmonary embolism and do some research on it. Methods： Pulmonary arteriography by DSA were performed in 6 goats and the stent was released in the infer-pulmonary arterary. Arterial blood gas analysis and right heart catheterization were done. After 3 days of embolism, pulmonary arteriography were performed again. After the animal was sacrificed, the right and left infer-pulmonary tissues were prepared and pathologically studied. Results： Stents were smoothly released in 6 animals. Compared with that before embolism, the arterial blood gas showed no difference 10 minutes later and 3 days later of the stent released. The pulmonary angiography showed that the right infra pulmonary artery was partly blocked and the blood could still pass by. 3 d of the embolism later, the stent was placed well and the right pulmonary artery was completely blocked. Compared with that before embolism,the right atrial pressure, ventricular pressure and the pulmonary pressure in 10 rain after embolism did not change much （ P 〉 0.05 ）, while 3 d after embolism, the pressures were obviously changed（P 〈 0.05 ）. There was no atelectasis ,pleural effusion in the right infra lobe in the experimental group. The wall of blood capillary among the alve- olar wall were significantly dilated. Hyperemia and edema were also observed. Lots of monocyte infiltrated. Localized exudates appeared in alveolar. Conclusion： By releasing stent in the pulmonary, the chronic pulmonary embolism model could be established in the animal experiment, and it should have great potential value in the following study.

Climate change and contrasting plasticity in timing of a two-step migration episode of an Arctic-nesting avian herbivore

Greenland white-fronted geese Anser albifrons flavirostris wintering in Britain and Ireland migrate over the sea for 700-1200 km to stage 3-5 weeks in Iceland in spring, continuing a similar distance over the sea and Greenland Ice Cap to West Greenland breeding grounds. During 1969 to 2012, the geese advanced the mean departure date from Ireland by 15 days, during which time also they attained threshold fat stores earlier as well as departing in fatter condition. Over that period, Iceland spring-staging geese shifted from consuming underground plant storage organs to grazing managed hayfields, which provide fresh grass growth despite sub-zero temperatures, when traditional natural foods are inaccessible in frozen substrates. In 2012 and 2013, geese arrived three weeks earlier to Iceland, in fatter condition and accumulated fat significantly slower than in 1997-1999 and 2007. Although geese accumulated sufficient fat stores earlier in Iceland in 2007, 2012 and 2013, they departed around the same date as in 1997-1999, prolonging spring staging by three weeks. Plasticity in winter departure dates is likely due to improved winter feeding conditions （enabling earlier departure in better condition） and a novel predictable food resource in Iceland. Greenland white-fronted geese attained threshold fat stores in Iceland earlier, but remained rather than departing earlier to Greenland. Despite arriving earlier in Iceland, arrival dates on the breeding areas have not changed since the 1880s, presumably because of relatively constant cool springs and heavy snowfall in West Greenland during recent years [Current Zoology 60 （2）： 233-242, 2014].

Characterization of the start-up behavior and steady-state performance of biotrickling filter removing low concentration toluene waste gas

A biotrickling filter packed with the regular ceramic spheres was designed and fabricated to purify the low toluene-concentration waste gas.Particular attention was made to the study of the start-up behavior of the biotrickling filter.Moreover,the steady performances were investigated to establish the experimental correlation between the operation factors and removal efficiency.It was found that the start-up process of the biotrickling filter exhibited three stages including the biofilm formation,biofilm development,and biofilm stabilization.The OD600 nm of the circulated liquid,gas pressure drop,elimination capacity,and temperature rise maintained at a rather low level in the biofilm formation stage,then increased rapidly in the biofilm development stage,and finally reached a stable value in the biofilm stabilization stage.It was also found that the removal efficiency of the biotrickling filter in the stable period decreased with increase in the waste gas flow rate,circulated liquid flow rate,and diameter of the ceramic sphere.More interestingly,it was revealed the operation modes have a significant influence on the removal efficiency of the biotrickling filter,and the microorganism show a high activity under the operating temperature ranging from 30°C to 40°C.The experimental correlations for describing the effect of operation factors on the removal efficiency of the biotrickling filters under both the co-current and counter-current operation modes were obtained.The correlation results are in good agreement with the experimental data.

Analyses of surrogate models for calculating thermophysical properties of aviation kerosene RP-3 at supercritical pressures

Aviation kerosene is commonly used in combustion and regenerative engine cooling processes in propulsion and power-generation systems,including rocket,scramjet,and advanced gas turbine engines.In this paper,many surrogate models proposed in the open literature are examined for their applicability and accuracy in calculating thermodynamic and transport properties of the China aviation kerosene RP-3 at supercritical pressures,based on the extended corresponding-states methods.The enthalpy change from endothermic decomposition and low heating value from combustion of the jet fuel are also evaluated.Results from a number of simple and representative surrogate models,which contain species components ranging from 1 to10,are analyzed in detail.Data analyses indicate that a surrogate model with four species is the best choice for thermophysical property calculations under the tested conditions,with fluid temperature up to 650 K at various supercritical pressures.The surrogate model is particularly accurate in predicting the pseudo-critical temperature of aviation kerosene RP-3 at a supercritical pressure.A simple surrogate model containing the n-decane species and a surrogate model containing 10 species are the other two acceptable options.The work conducted herein is of practical importance for theoretical analyses and numerical simulations of various physicochemical processes at engine operating conditions.

Studies on aeroservoelasticity semi-physical simulation test for missiles

Missiles may be damaged when aeroservoelastic problem occurs,which is caused by the interaction of structure flexibility and flight control system.Because of the limit of wind tunnel test condition,numerical methods are mostly used in previous aeroservoelastic studies.However,series of assumptions and simplification on structures,aerodynamics and flight control systems are unavoidably introduced,and various nonlinear factors are also ignored,therefore,they result in considerable errors.A novel method called aeroservoelasticity semi-physical simulation test is proposed in this paper,which takes the flexible missile with control system as the test object.Vibration signals at several locations of the missile are measured by accelerometers,then corresponding unsteady aerodynamics is computed based on the fact that airflow at high Mach is nearly quasi-steady,and finally unsteady aerodynamics is exerted simultaneously by shakers at certain locations of the missile.The aeroservoelasticity semi-physical simulation test system can be constructed after the control system is closed.Open loop transfer function test and closed loop stability test are carried out in sequence.The test principle and method proposed in this paper are verified by the concordance between the results of numerical simulation and experiment.