轻工自动机引进线上常用的气动控制法—凸轮组式气控法

本文通过对近年来引进的轻工自动机气动控制法的分析，对凸轮组式气控法的基本原理、工作特点、常用的三种基本回路进行了详细的叙述和比较，最后对选用原则、安全保护及应用前景提出了指导性的看法。

利用气控方法防治储粮害虫的研究

近年来,使用调节大气气体的浓度来防治储粮害虫已经取得显著的进展。已经表明,使用含有低氧的氮气,高浓度的二氧化碳或这些气体的混合物作为非化学防治的有效方法来防治昆虫的危害是可行的。但是在粮堆的生态系统中,大气气体的组成只是影响昆虫繁殖的因素之一,影响储粮害虫生存的其它环境因素还有温度和相对湿度。所以,有效地使用气控储藏必须细心地考虑这两个因素的有关数据,在某些情况下可以改变温度和相对湿度来增加气控防治方法的效力。

基于等离子体反应器的室内空气净化装置研究

在对比若干室内空气净化方法之后 ,介绍了等离子体空气净化的能力、机理以及光催化反应 ,对基于等离子体反应器的室内空气净化典型装置进行系统分析。对等离子体空气净化技术的研究进行了展望 ,指出存在的问题和发展的方向。

饲料厂储粮害虫防治措施

1 高温杀虫对于已感染害虫的高水分粮食或饲料,可以利用烘干机进行烘干处理,即可杀灭害虫,又可以降低水分;另外,在严热的夏季,可以采用日光曝晒进行杀虫,一般害虫在38～40 ℃的环境里就渐渐丧失活动能力,当温度上升到45 ℃以上时,经过2小时就要死亡,而在炎热的夏季太阳直射可使粮食或饲料温度升到50 ℃左右,这时几乎所有的害虫都可致死.

Some Trials of Typical Typhoon Tracks Using the Adjoint Method

In this paper, the adjoint method is applied to the statistical-dynamic model （SD-90） for the prediction of typhoon tracks along with the regularization thinking and optimal control techniques. The adjoint model and the gradient of objective function are deduced with the continual model respectively. For 4 typical typhoons, the forces and the initial velocity can be retrieved well, and the tracks of these typhoons are accurately fitted for an appropriate regularization parameter and optimal control parameter.

1-D Controlled source electromagnetic forward modeling for marine gas hydrates studies

We discuss the feasibility of using controlled-source electromagnetic （CSEM） in the frequency domain for prospecting marine gas hydrates. Based on the Ocean Drilling Program （ODP） Leg 164 log data, we have established several 1-D resistivity models which have different gas hydrate concentrations. Meanwhile, we analyzed the electromagnetic response of marine gas hydrates in the frequency domain based on these models. We also studied the relationship between electrical field magnitude or phase and parameters such as receiver-transmitter distance and frequency. Our numerical modeling results provide us with a quantitative reference for exploration and resource evaluation of marine gas hydrates.

Sulfur-mediated photodeposition synthesis of NiS cocatalyst for boosting H2-evolution performance of g-C3N4 photocatalyst

Modification of nickel sulfide cocatalysts is considered to be a promising approach for efficient enhancement of the photocatalytic hydrogen production performance of g-C3N4.Providing more NiS cocatalyst to function as active sites of g-C3N4 is still highly desirable.To realize this goal,in this work,a facile sulfur-mediated photodeposition approach was developed.Specifically,photogenerated electrons excited by visible light reduce the S molecules absorbed on g-C3N4 surface to S^2‒,and subsequently NiS cocatalyst is formed in situ on the g-C3N4 surface by a combination of Ni2+and S2‒due to their small solubility product constant(Ksp=3.2×10^‒19).This approach has several advantages.The NiS cocatalyst is clearly in situ deposited on the photogenerated electron transfer sites of g-C3N4,and thus provides more active sites for H2 production.In addition,this method utilizes solar energy with mild reaction conditions at room temperature.Consequently,the synthesized NiS/g-C3N4 photocatalyst achieves excellent hydrogen generation performance with the performance of the optimal sample(244μmol h^‒1 g^‒1)close to that of 1 wt%Pt/g-C3N4(316μmol h^‒1 g^‒1,a well-known excellent photocatalyst).More importantly,the present sulfur-mediated photodeposition route is versatile and facile and can be used to deposit various metal sulfides such as CoSx,CuSx and AgSx on the g-C3N4 surface,and all the resulting metal sulfide-modified g-C3N4 photocatalysts exhibit improved H2-production performance.Our study offers a novel insight for the synthesis of high-efficiency photocatalysts.

Control of combustion area using electrical resistivity method for underground coal gasification

Underground coal gasification （UCG） is one of the clean technologies to collect heat energy and gases （hydrogen, methane, etc.） in an underground coal seam. It is necessary to further developing environ- mentally friendly UCG system construction. One of the most important UCG＇s problems is underground control of combustion area for efficient gas production, estimation of subsidence and gas leakage to the surface. For this objective, laboratory experiments were conducted according to the UCG model to iden- ti[y the process of combustion cavity development by monitoring the electrical resistivity activity on the coal samples to setup fundamental data for the technology engineering to evaluate combustion area. While burning coal specimens, that had been sampled from various coal deposits, electrical resistivity was monitored. Symmetric four electrodes system （ABMN） of direct and low-frequency current electric resistance method was used for laboratory resistivity measurement of rock samples. Made research and the results suggest that front-end of electro conductivity activity during heating and combusting of coal specimen depended on heating temperature. Combusting coal electro conductivity has compli- cated multistage type of change. Electrical resistivity method is expected to be a useful geophysical tool to for evaluation of combustion volume and its migration in the coal seam.

An Adsorption Kinetic Model for Sulfur Dioxide Adsorption by ZL50 Activated Carbon

A semi-empirical adsorption kinetic model was proposed with the time compensation method to describe the chemisorption of SO2 in flue gas by carbon adsorbents for flue gas purification.The change in adsorption capacity and adsorption rate with time at different water vapor concentrations and different SO2 concentrations was studied.The model was in good agreement with experimental data.The surface reaction was probably the rate controlling step in the early stage for SO2 adsorption by ZL50 activated carbon.The parameters m and n in the nth order adsorption kinetic model were related to the magnitude of the time compensation and adsorption driving force,respectively.The change of parameter n with water vapor concentrations and sulfur dioxide concentrations was studied and some physical implications were given.The sum of square errors was less than 1.0 and the average absolute percentage deviations ranged from 0.5 to 3.2.The kinetic model was compared with other models in the literature.

Removal of the airwave effect by main-part decomposition of the anomalous field of MCSEM data

The airwave effect greatly influences the observational data from controlledsource electromagnetic exploration in shallow seas, which obscures the abnormal effects generated by exploration targets and, hence, affects the accuracy of the late exploration data interpretation. In this study, we propose a method to separate the main part from the anomalous field of marine controlled-source electromagnetic method （MCSEM） data based on Stratton-Chu integral transforms to eliminate the airwave effect, which dominates observed electromagnetic （EM） response in shallow seawater. This method of separating the main part from the anomalous field is a type of finite impulse response filter based on a discrete data set. Theoretical analysis proved that the method is stable and able to effectively depress noise. A numerical test indicated that the method could successfully eliminate the airwave effect from the observed EM signals generated by an air water interface and a seawater layer. This technique is applicable for seawater models with either flat or rough seabeds.

Energy Efficient Predictive Control for Vapor Compression Refrigeration Cycle Systems

Abstract--Vapor compression refrigeration cycle （VCC） system is a high dimensional coupling thermodynamic system for which the controller design is a great challenge. In this paper, a model predictive control based energy efficient control strategy which aims at maximizing the system efficiency is proposed. Firstly, according to the mass and energy conservation law, an analysis on the nonlinear relationship between superheat and cooling load is carried out, which can produce the maximal effect on the system performance. Then a model predictive control （MPC） based controller is developed for tracking the calculated setting curve of superheat degree and pressure difference based on model identified from data which can be obtained from an experimental rig. The proposed control strategy maximizes the coefficient of performance （COP） which depends on operating conditions, in the meantime, it meets the changing demands of cooling capacity. The effectiveness of the control performance is validated on the experimental rig. Index Terms--Cooling load, model predictive control （MPC）, superheat, vapor compression refrigeration cycle （VCC）.

Modeling and analysis of moving-mass actuated stratospheric airship

A moving-mass control method is introduced to stratospheric airship for its special working condition of low atmospheric density and low speed.The dynamic equation of airship is derived by using the Newton-Euler method and the mechanism of attitude control by moving masses is studied.Then the passive gliding of airship by the moving masses is given based on the theory of glider,and attitude control capability between moving mass and elevator is compared at different airspeed.Analysis results show that the motion of masses changes the gravity center of the airship system,which makes the inertia tensor and the gravity moment vary.Meanwhile,the aerodynamic angles are generated,which results in the change of aerodynamic moment.Control efficiency of moving masses is independent of airspeed.Thus the moving-mass control has the advantage over the aerodynamic surfaces at low airspeed.

Super-resolution least-squares prestack Kirchhoff depth migration using the L_0-norm

Least-squares migration （LSM） is applied to image subsurface structures and lithology by minimizing the objective function of the observed seismic and reverse-time migration residual data of various underground reflectivity models. LSM reduces the migration artifacts, enhances the spatial resolution of the migrated images, and yields a more accurate subsurface reflectivity distribution than that of standard migration. The introduction of regularization constraints effectively improves the stability of the least-squares offset. The commonly used regularization terms are based on the L2-norm, which smooths the migration results, e.g., by smearing the reflectivities, while providing stability. However, in exploration geophysics, reflection structures based on velocity and density are generally observed to be discontinuous in depth, illustrating sparse reflectance. To obtain a sparse migration profile, we propose the super-resolution least-squares Kirchhoff prestack depth migration by solving the L0-norm-constrained optimization problem. Additionally, we introduce a two-stage iterative soft and hard thresholding algorithm to retrieve the super-resolution reflectivity distribution. Further, the proposed algorithm is applied to complex synthetic data. Furthermore, the sensitivity of the proposed algorithm to noise and the dominant frequency of the source wavelet was evaluated. Finally, we conclude that the proposed method improves the spatial resolution and achieves impulse-like reflectivity distribution and can be applied to structural interpretations and complex subsurface imaging.

Gas Chromatography-Based Fingerprinting and Chemical Pattern Recognition of Rosa multiflora Volatile Oil

In this paper, gas chromatography-mass spectrometry （GS-MS） was used to build the standard fingerprint of volatile oil from Rosa multiflora Thunb. from 12 different habitats. Fourteen components in the volatile oil were identified as the indicator components ofR. multiflora, of which one was selected as the standard. The GC analysis conditions used for fingerprinting afford a very good separating effect. The similarity of the 12 volatile oils from R. multiflora Thunb. was more than 0.84, and the precision, stability and repeatability of the fingerprints were quite good. It could be concluded that the fingerprints can be used as the standard and as a quality control method for medicinal materials from R. multiflora Thunb..

Robust parametric approach for tracking control of an air-breathing hypersonic cruise vehicle

To realize the stabilization and the tracking of flight control for an air-breathing hypersonic cruise vehicle, the linearization of the longitudinal model under trimmed cruise condition is processed firstly. Furthermore, the flight control problem is formulated as a robust model tracking control problem. And then, based on the robust parametric approach, eigenstructure assignment and reference model tracking theory, a parametric optimization method for robust controller design is presented. The simulation results show the effectiveness of the proposed approach.

Size and shape controllable preparation of graphene sponge by freezing, lyophilizing and reducing in container

Graphene sponge(GS) is a porous 3D structure of graphene. Although hydrothermal reduction, chemical vapor deposition, solution reduction and high temperature annealing could be used for the preparation of GS, the size and shape cannot be well controlled. Herein, we reported a facile method to prepare GS under mild condition in a size and shape controllable way. Graphene oxide was lyophilized to form the spongy structure and reduced by steamy hydrazine hydrate to produce GS. The size and shape of GS prepared were nearly identical to that of the container. The reduction degree of GS could be regulated by the reduction temperature and time.

Lift enhancement method by synthetic jet circulation control

A novel circulation control technique is proposed to overcome the shortcomings of blowing jet circulation control, which uses the synthetic jet as the actuator and avoids the limitation about air supply requirement. The effectiveness of synthetic jet circulation control to enhance lift of NCCR1510-7067N airfoil is confirmed by solving the 2-D unsteady Reynolds-averaged Na- vier-Stokes equations. The aerodynamic characteristics and the flow structure （especially close to the trailing edge） of NCCR 1510-7067N airfoil at zero angle of attack are also presented to discuss the mechanism of lift enhancement of the airfoil with synthetic jet circulation control. The results indicate that the synthetic jet can effectively delay the separation point on the airfoil trailing edge and increase the circulation and lift of the airfoil by Coanda effect. The numerical simulation results demonstrate that the lift augmentation efficiency with synthetic jet circulation control reaches △C1/Cμ,=114 in the present study, which is much higher than the value 12.1 in the case with steady blowing jet circulation control.

Some important aspects of wind-resistant studies on long-span bridges

In recent years many long-span bridges have been or are being constructed in the world, especially in China. Wind loads and responses are the key factors for their structural design. This paper introduces some important achievements of wind-resistant studies of the author's research team on long-span bridges. First, new concepts and identification methods of aerodynamic derivatives and aerodynamic admittances were proposed. Then mechanical and aerodynamic control strategies and methods of wind-induced vibrations of long-span bridges were the great concerned problems, and valuable achievements were presented. Especially, great efforts which have been theoretically and experimentally made on rain-wind induced vibration of cables of cable-stayed bridges were described. Finally, some new progresses in computation wind engineering were introduced, and a new method for simulating an equilibrium boundary layer was put forward as well.