The Al-Ni-Y alloy powder was prepared by rapid solidification technology of inert gas atomization. The diameter of amorphous powder is less than 12 µm. The effects of atomization gas on cooling velocity, morphology, microstructure and microhardness of powder and fine powder ratio were investigated. The results show that the morphology, microstructure and microhardness of powder and fine powder ratio are affected by cooling velocity changed through atomization gas. The cooling velocity of inert gas atomization is more than 1×10⁴ K/s. The larger the cooling velocity, the finer the powder, and the smoother the surface of powder; the smaller the diameter of powder, the larger the microhardness of powder.

The distribution of Al(j) and the structural units distribution of Q_Tⁱ in calcium aluminosilicate melts were studied by means of molecular dynamics simulation. The results show that provided there exists lower-field strength cation relative to Al³⁺, such as alkaline and alkaline earth metals, Al will be four-coordinated but not six-coordinated. Meanwhile, if there exist a large number of higher-field strength cations such as Si⁴⁺ and little lower-field strength cation, six-coordinated aluminum will be formed. The relation of structural units distribution of Q_Tⁱ with chemical composition shift was also extracted, showing that as Ca²⁺ exists, the distributions of Q_Siⁱ, Q_Alⁱ or Q_Tⁱ have the similar changing trend with the variation of component. Because of high-temperature effect, the Al-tetrahedral units in melts are greatly active and unstable and there exist dynamic transforming equilibria of Al(3) ⇋ Al(4) and Al(5) ⇋ Al(4). The three-coordinated oxygen and charge-compensated bridging oxygen are proposed to explain phenomena of the negative charge redundancy of AlO₄ and location of network modifier with charge-compensated function in aluminosilicate melts.

The halide-activated pack cementation process was used to form molybdenum diffusion coating on titanium substrate. The morphology, structure, elements diffusion distribution and microhardness of the coatings formed at different diffusion temperatures were studied. The results indicate that the coating is made up of deposition layer and diffusion layer, and the surface roughness of specimens is increased after diffusion. In the diffusion layer, the major phases are Mo and β-Ti phase with addition of α′-Ti phase and α″-Ti phase. And the phase composition of Mo →β→β″→β′ is formed for different Mo contents in the diffusion layer from outside to inside. The diffusion of Ti element is very obvious as well as Mo element. With increasing the diffusion temperature, the thickness of diffusion layer is increased rapidly, and the microhardness is changed more smoothly with diffusion depth, which shows the same distribution rules as the Mo content.

Based on the fatigue prediction model of exponential function and Whitney-Nuismer(WN) criterion of static strength for the composite material laminate with a circular hole, the stress correct factor (β) was put forward and a new fatigue prediction model for composite material laminate was set up. T300/KH304, which is recently studied and is a high capability composite material, was used as the raw material. In order to gain the factor β, the fatigue experiments of the laminates with holes in different diameters and the same ratio of width to diameter were conducted. The fatigue analysis and tests of the laminates with a hole 5 mm in diameter are carried out at different stress levels, and the results meet the engineering requirement. The simple, prompt and practical method is provided for the prediction of S-N curve of composite laminate with a circular hole.

Measurements of the effects of tensile stress on magnetic field properties, infrared thermography and acoustic emission of a cuboid sample with an elliptical hole in its center were presented. The tensile stress was applied perpendicularly to the sample by electro-tension machine according to a step-loading curve. The changes of the sample temperature was recorded by an infrared thermography system and the noise of domain reversal was inspected by two acoustic probes, which were placed on each end of the sample near the collets of the electro-tension machine, when the sample was in loading process. The magnetic fields on the surface of the sample were inspected with 8 mm lift-off when the loads were held. Valuable information about the changes of domains was obtained from analysis of acoustic emission signals in loading process. Infrared images of the sample provided complementary information about the state of the sample. The results show that stress concentration in ferromagnetic material affects the direction and structure of domain and generates net magnetic moment on its surface. The distribution and magnitude of the net magnetic moment are correlative with those of stress.

Back-propagation artificial neural network (BPANN) is used in ball backward spinning in order to form thin-walled tubular parts with longitudinal inner ribs. By selecting the process parameters which have a great influence on the height of inner ribs as well as fish scale on the surfaceof the spun part, a BPANN of 3-8-1 structure is established for predicting the height of inner rib and recognizing the fish scale defect. Experiments data have proved that the average relative error between the measured value and the predicted value of the height of inner rib is not more than 5%. It is evident that BPANN can not only predict the height of inner ribs of the spun part accurately, but recognize and prevent the occurrence of the quality defect of fish scale successfully, and combining BPANN with the ball backward spinning is essential to obtain the desired spun part.

Based on the power dissipating model of spherical sample in free convection gas medium and the expression of input power, the model of temperature calculation for electromagnetic levitation melting sample was established. Considering the limitation of levitation force and levitation sample temperature, the principle of stability levitation zone computation was determined. A spherical sample (ThDy)Fe₂ under the protection of argon gas was examined, and the effect of radius of levitation sample and perturbation on the stable levitation zone was investigated. The results show that longitudinal perturbation and transverse perturbation can shorten the length of stable levitation zone and the range of levitation sample radius. By increasing the sample radius and weakening the perturbation the electromagnetic levitation melting stability of sample can be improved.

Thiobacillus ferrooxidans might be the most important bacteria used in biometallurgy. The foundation way of its growth process is oxidizing ferrous in order to obtain energy needed for metabolism, but the variation of ferrous concentration and mixed potential of the culture media would have crucial effect on the bacteria growth. Based on the characteristics of Thiobacillus ferroxidans growth and redox potential of ferric and ferrous, an electrochemical cell was designed conventionally to study growth rule and the relationship between redox potential and bacteria growth was built up, and some growth kinetics of Thiobacillus ferrooxidans were elucidated. It demonstrates that the variation of open potential of electrochemical cell ΔE shows the growth tendency of Thiobacillus ferrooxidans, at the initial growth stage, the value of δE increases slowly, when at logistic growth stage, it increases drastically, and the growth rate of bacteria is linear with the oxidation rate of ferrous. The bacteria growth kinetics model is proposed using Monod and Michealis-Menten equation, and the kinetics parameters are got. The consistence of the measured and the calculated results proves that it is proper to use the proposed kinetics model and the electrochemical cell method to describe the growth rule of Thiobacillus ferrooxidans.

Cement production is characterized by its great capacity, long-time delay, multi variables, difficult measurement and multi disturbances. According to the distributed intelligent control strategy based on the multi agent, the multi agent control system of cement production is built, which includes integrated optimal control and diagnosis control. The distributed and multiple level structure of multi agent system for the cement control is studied. The optimal agent is in the distributed state, which aims at the partial process of the cement production, and forms the optimal layer. The diagnosis agent located on the diagnosis layer is the diagnosis unit which aims at the whole process of the cement production, and the central management unit of the system. The system cooperation is realized by the communication among optimal agents and diagnosis agent. The architecture of the optimal agent and the diagnosis agent are designed. The detailed functions of the optimal agent and the diagnosis agent are analyzed. At last the realization methods of the agents are given, and the application of the multi agent control system is presented. The multi agent system has been successfully applied to the off-line control of one cement plant with capacity of 5 000 t/d. The results show that the average yield of the clinker increases 9.3% and the coal consumption decreases 7.5 kg/t.

A new direct recycling technology was developed to recover the valuable metals present in the stainless steelmaking dust and protect the environment. The agglomeration behavior of the dust was analyzed to ensure the requirements of the direct recycling. The main characteristics such as strength, leachability, structure and chemical composition of the pellets were investigated. SEM images show a significant amount of porosities affecting the strength of the pellets and the arrangement of particles in the pellets reveals that no recrystallization bonds are formed, resulting in the poor strength of the pellets. When lignosulfonate is applied as the binder for the agglomeration and the green pellets are dried at room temperature for 60 h, the strong pellets can be obtained without milling the dust. The result of leachability tests shows that the pellets agglomerated can not satisfy the regulations set by the environmental protection agency of US. And it will cause some environmental problems in the long storage of pellets.

Large and uniform tetrapod-like ZnO whiskers (T-ZnO) were prepared from waste hot dipping zinc by vapor oxidation and examined by means of X-ray diffraction and ICP-AES analysis and scanning electron microscope. The products are pure hexagonal wurtzite crystals with tetrapod shape and edge size of center body 5–6 µm and needle length of 100–130 µm. The size and shape of ZnO particles are fully controlled by the growth conditions and T-ZnO can be obtained only at 850–1000 °C and total gas flow rate ranging from 40 to 250 L · h⁻¹ in which the size of the T-ZnO particles varies slightly with temperature. The process of the formation of T-ZnO is that T-ZnO may nucleate at the initial stage with a complete tetrapod shape and develop to the large size, but not the process of preferential growth of octahedral nuclei and subsequent growth of the needles. The experiment presents a new method to prepare T-ZnO economically by using the waste hot dipping zinc.

The sewage sludge was used to produce adsorbent by controlling the pyrolytic and chemical conditions. Using the adsorbent derived from sewage sludge to adsorb the low concentration SO₂ in fixed bed system, the effects of the metallic derivatives on characteristics of the adsorbent were investigated at different compositions of the gaseous mixtures. The results show that when the mass fraction of vanadium reaches 0.5% and the mass fraction of iron, calcium, copper, nickel reach approximately 0.9%, under the condition that the adsorption mixture contains 0.12%SO₂, 3%O₂ and 10% water vapor, the maximum adsorption capacity of SO₂ can be obtained to be 128, 109, 90, 82, 78 mg · g⁻¹, respectively. So the metallic derivatives fixed onto adsorbent derived from sewage sludge especially vanadium have great effects on of the sorption characteristics of the adsorbent with respect to SO₂.

3β-acetoxy-17, 17-ethylendioxy-15β, 16β-methylene-5-androsten-7β-ol(I) was prepared by 3 steps from 3β-acetoxy-15β, 16β-methylene-5-androsten-17-one (II) with overall yield of 52.7%. Thus, interaction of ethylene glycol and material (II) gave 3β-acetoxy- 17, 17-ethylendioxy-15β, 16β-methylene-5-androsten (III) which was subsequently oxidated and stereoselectively reduced to produce compound(I). The normal influencing factors, such as the types of oxidants and reductives, the mole ratio of reactants, the reaction temperature, and the addition ways of reactants, in oxidation and reduction were discussed. The results show that the oxidation rate order is CrO₃-C₅H₅N (1:1, mole fraction)>CrO₃-C₅H₅N(1:2)>(C₅H₅NH)₂Cr₂O₇ in terms of the oxidant, the yield of the oxidation becomes higher with increasing the oxidant stoichiometry and raising the reaction temperature. And the optimum condition is that the reaction temperature is at 30 °C, and n(III)/n(CrO₃-C₅H₅N(1:2)=1:20. The yield of the −7β alcohol order with Li[Al(OC(CH₃)₃)₃H] (e. g. 78.6%) is more than that with NaBH₄ (e. g. 14.5%) in terms of the reductive agent and the reduction rate decreases in the course of reaction. The compound (I) is characterized by IR and MS.

A detailed analysis of mode II stress intensity factors(SIFs) for the double edge cracked Brazilian disk subjected to different diametral compression is presented using a weight function method. The model II SIFs at crack tips can be obtained by simply calculating an integral of the product of mode II weight function and the shear stress on the prospective crack faces of uncracked disk loaded by a diametral compression. A semi-analytical formula for the calculation of normalized mode II SIF, f_II, is derived for different crack lengths (from 0.1 to 0.7) and inclination angles (from 10° to 75°) with respect to loading direction. Comparison between the obtained results and finite element method solutions shows that the weight function method is of high precision. Combined with the authors’ previous work on mode I fracture analysis, the new specimen geometry can be used to study fracture through any combination of mode I and mode II loading by a simple alignment of the crack relative to the diameter of compression loading, and to obtain pure mode II crack extension. Another advantage of this specimen geometry is that it is available directly from rock core and is also easy to fabricate.

Traditionally, it is widely accepted that measurement error usually obeys the normal distribution. However, in this paper a new idea is proposed that the error in digitized data which is a major derived data source in GIS does not obey the normal distribution but the p-norm distribution with a determinate parameter. Assuming that the error is random and has the same statistical properties, the probability density function of the normal distribution, Laplace distribution and p-norm distribution are derived based on the arithmetic mean axiom, median axiom and p-median axiom, which means that the normal distribution is only one of these distributions but not the least one. Based on this idea, distribution fitness tests such as Skewness and Kurtosis coefficient test, Pearson chi-square x₂ test and Kolmogorov test for digitized data are conducted. The results show that the error in map digitization obeys the p-norm distribution whose parameter is close to 1.60. A least p-norm estimation and the least square estimation of digitized data are further analyzed, showing that the least p-norm adjustment is better than the least square adjustment for digitized data processing in GIS.

The initial shear stress (τ) and plastic cohesion (η) are the most important parameters reflecting the rheological properties of the paste slurry. The rheological parameters as well as the quantitative relationship among the consumption of different fill materials were obtained through the experiment and research on these parameters. They can be used to predict the scope of the values of τ and η in production for a given ratio, which can reduce the conveying resistance of fill slurry along the pipelines and avoid the blockage of the pipelines. It is found that the rheological model of the total tailing slurry belongs to the Bingham type, which has a feature of strong internal structure and large initial shear stress. The calculation formula for the resistance loss of pipelines conforms nicely to the field test and the actual production in Jinchuan Nickel Mine.

The Sangzhi-Shimen synclinorium, which is in the western margin region of the Hunan-Hubei Province and as the southeast part of the middle Yangtze platform, is a second-level tectonics unit in the south of this region. Along the profile, it can be divided into 5 third-level structure belts. By the comprehensive interpretation of seismic data and magnetotelluric (MT) sounding data, it is found that the surface structure is not in accordance with that of the underground, and this un-coordination can be conducted by many decollement surfaces between the layers. There are three periods of deformation in its geo-history in this region: before the early Yanshan stage, during the early Yanshan stage and after the early Yanshan stage, while the main deformation period is during the early Yanshan stage. And the mechanism of deformation is the thrust faults in basement, which are controlled by many decollements, in addition to the decollement of the cap-rock.

Current design method for circular sliding slopes is not so reasonable that it often results in slope sliding. As a result, artificial neural network (ANN) is used to establish an artificial neural network based inverse design method for circular sliding slopes. A sample set containing 21 successful circular sliding slopes excavated in the past is used to train the network. A test sample of 3 successful circular sliding slopes excavated in the past is used to test the trained network. The test results show that the ANN based inverse design method is valid and can be applied to the design of circular sliding slopes.

Decentralized H_∞ control was studied for a class of interconnected uncertain systems with multiple delays in the state and control and time varying but norm-bounded parametric uncertainties. A sufficient condition which makes the closed-loop system decentralized asymptotically stable with H_∞ performance was derived based on Lyapunov stability theorem. This condition is expressed as the solvability problem of linear matrix inequalities. The method overcomes the limitations of the existing algebraic Riccati equation method. Finally, a numerical example was given to demonstrate the design procedure for the decentralized H_∞ state feedback controller.

In order to overcome difficulty of tuning parameters of fuzzy controller, a chaos optimal design method based on annealing strategy is proposed. First, apply the chaotic variables to search for parameters of fuzzy controller, and transform the optimal variables into chaotic variables by carrier-wave method. Making use of the intrinsic stochastic property and ergodicity of chaos movement to escape from the local minimum and direct optimization searching within global range, an approximate global optimal solution is obtained. Then, the chaos local searching and optimization based on annealing strategy are cited, the parameters are optimized again within the limits of the approximate global optimal solution, the optimization is realized by means of combination of global and partial chaos searching, which can converge quickly to global optimal value. Finally, the third order system and discrete nonlinear system are simulated and compared with traditional method of fuzzy control. The results show that the new chaos optimal design method is superior to fuzzy control method, and that the control results are of high precision, with no overshoot and fast response.

Based on Lyapunov stability theory, a design method for the robust stabilization problem of a class of nonlinear systems with uncertain parameters is presented. The design procedure is divided into two steps: the first is to design controllers for the nominal system and make the system asymptotically stabilize at the expected equilibrium point; the second is to construct closed-loop nominal system based on the first step, then design robust controller to make the error of state between the original system and the nominal system converge to zero, thereby a dynamic controller with the constructed closed-loop nominal system served as interior dynamic is obtained. A numerical simulation verifies the correctness of the design method.

The calculation precision and convergence speed of streamline strip element method are increased by using the method whose initial value of the exit lateral displacement is determined with strip element variation method, and the accurate tension lateral distribution model is adopted based on the original third power spline function streamline strip element method. The basic theory of the strip element method is developed. The calculated results by the improved streamline strip element method and the original streamline strip element method are compared with the measured results, showing that the calculated results of the improved method are in good agreement with the measured results.

For a class of quintic systems, the first 16 critical point quantities are obtained by computer algebraic system Mathematica, and the necessary and sufficient conditions that there exists an exact integral in a neighborhood of the origin are also given. The technique employed is essentially different from usual ones. The recursive formula for computation of critical point quantities is linear and then avoids complex integral operations. Some results show an interesting contrast with the related results on quadratic systems.