The effects of the addition of Mo on the densification mechanism, microstructure evolution and mechanical strength of blended elemental powder metallurgy Ti-Mo alloy were investigated in this work. The results show that the addition of Mo hinders the densification of Ti-Mo alloy due to the low diffusion rate of Mo atoms in β-Ti matrix, and the increase of Mo content worsens the sinterability of Ti-Mo alloy. However, the addition of Mo can also refine the microstructure of Ti-Mo alloy greatly, and raising sintering temperature can effectively increase the alloy density without grain coarsening. When neglecting the relative density factor, the addition of Mo refines the microstructure, and improves the mechanical strength by Hall-Petch relationship.

The effects of sodium carboxymethyl cellulose and sodium citrate as dispersants on nano-ceramic aqueous suspension were examined by the measurements of ζ-potential and the sedimentation test. The results show that proper addition of sodium carboxymethyl cellulose or sodium citrate into nano-ceramic coating, exhibits an enhanced dispersion and stability compared with the coating without dispersants. The negative ζ-potential of the particles in the nano-coating increases with the increase of pH value of the coating, and the curve of ζ-pH moves to lower pH range when the dispersants are added into the coating. To ensure that the coating has not only good stability and dispersibility but also no corrosivity to substrate alloy, adding 1.00% sodium citrate into coating with pH value of 7–8 is preferable to adding sodium carboxymethyl cellulose.

Alloy thin film for advanced pressure sensors was manufactured by means of ion-beam sputtering SiO₂ insulation film and NiCr thin film on the 17-4PH stainless steel elastic substrate. The thin film resistance was respectively heat-treated by four processes. The effects on stability of thin film alloy resistance were investigated, and paramaters of heat treatment that make thin film resistance stable were obtained. The experimental result indicates that the most stable thin film resistance can be obtained when it is heat-treated under protection of SiO₂ and N₂ at 673 K for 1 h, and then kept at 473 K for 24 h. Pressure sensor chips of high precision for harsh environments can be manufactured by this process.

Au-Zr binary system was reassessed by using the calculation phase diagram (CALPHAD) technique based on experimental thermodynamic data and newly reported phase diagrams. The excess Gibbs energies of the three terminal solutions and the liquid phases were formulated with Redlich-Kister polynomial. All the intermetallic phases were treated as stoichiometric compounds with the exception of ZrAu which is modeled by a two-sublattice model, (Au,Zr) : (Au,Zr). The results show that there exist seven intermetallics: Zr₃Au, Zr₂Au, Zr₅Au₄, Zr₇Au₁₀, ZrAu₂, ZrAu₃, and ZrAu₄ in the system. The eutectoid reaction: β(Zr) → α(Zr)+Zr₃Au takes place at 1048 K and the maximal solubility of Au in α-Zr is 4.7% (mole fraction). The maximal solubility of Zr in Au is 6.0% (mole fraction) at 1347 K. The homogeneity range of ZrAu phase is about 44.5%–52.9% (mole fraction) of Au. The present assessment fits experimental data very well.

The recovery of zinc from low-grade zinc oxide ores with solvent extraction-electrowinning technique was investigated by using D2EHPA as extractant and 260^# kerosene as diluent. The results show that it is possible to selectively leach zinc from the ores by heap leaching. The zinc concentration of leach solution in the first leaching cycle is 32.57 g/L, and in the sixteenth cycle the zinc concentration is 8.27g/L after solvent extraction. The leaching solution is subjected to solvent extraction, scrubbing and selective stripping for enrichment of zinc and removal of impurities. The pregnant zinc sulfate solution produced from the stripping cycle is suitable for zinc electrowinning. Extra-pure zinc metal was obtained in the electrowinning test under conventional conditions.

Two kinds of novel chitosan-crown ether resins, Schiff base type chitosan-benzo-15-crown-5 (CTS-B15) and chitosan-benzo-18-crown-6 (CTS-B18), were synthesized through the reaction between -NH₂ in chitosan and —CHO in 4′-formyl benzo-crown ethers. Their structures were characterized by elemental analysis and FT-IR spectra analysis. The elemental analysis results show that the mass fractions of nitrogen in CTS-B15 and CTS-B18 are much lower than those of chitosan. The results of FT-IR spectra of CTS-B15 and CTS-B18 reveal that there exist characteristic peak of C=N, N-H and Ar, and characteristic peak of pyr anoside in the chain of chitosan-crown ether resins, showing that the structures of chitosan-crown ethers are as expected. The adsorption properties of CTS-B15 and CTS-B18 for Pd²⁺, Cu²⁺ and Hg²⁺ were studied and the experimental results show that these adsorbents have both good adsorption characterization and especially high particular adsorption selectivity for Pd²⁺ when Cu²⁺ and Hg²⁺ are in coexistence, and the coefficients of selectivity of CTS-B15 and CTS-B18 for metal ions are K_Pd²⁺_/Cu²⁺=7.56, K_Pd²⁺_/Hg²⁺=68.00, K_Cu²⁺_/Hg²⁺=9.00 and K_Pd²⁺_/Cu²⁺=6.00, K_Pd²⁺_/Hg²⁺=19.00, K_Cu²⁺_/Hg²⁺=3.00, respectively.

Based on the principle of life cycle assessment, CO₂ and SO₂ emission of Imperial Smelting Process in a certain zinc-lead smelter was analyzed by life cycle inventory method. According to the system expansion and substitution method, the environmental impacts of co-products were allocated among the main products of zinc, lead and sulfuric acid. The related impacts were assessed by use of Global Warming Potential (GWP) and Acidification Potential (ACP). The results show that the GWP index from 1998 to 2000 is 11.53, 11.65, 10.93 tCO₂-eq/tZn respectively, the ACP index decreases from 14.88 kgSO₂-eq/tZn in 1998 to 10.99 kgSO₂-eq/tZn in 2000. Power and electricity generation, followed by smelting and zinc distillation, are mainly responsible for GWP. Sintering individually affects ACP. Reduction in greenhouse gas emissions of the ISP may come from energy conservation measures rather than from technological developments. And recycling more secondary Pb and Zn materials effectively treated by ISP, and reducing the amount of primary metal are the main ways to put SO₂ emission under control.

By orthodox experiment, the main influence factors of desulfurization by sul folobas of pH value, temperature, coal slurry concentration and coal granularity are studied in detail and the optimal experimental conditions were also obtained. The experimental results demonstrate that sul folobas being kind of linking-heat, acidophilic and self-supported bacterium with double characters can effectively remove inorganic and organic sulfur in coal. The superlatively desulfurization rate is up to 48.57% total sulfur and 41.71% inorganic sulfur within 10 d and its desulfurization rate can be greatly affected by the four factors above mentioned. Therefore, the optimum conditions of desulfurization are obtained by comprehensive experiment and they are as following: pH value 3, temperature 70°C, coal slurry concentration 10% and coal granularity 150 µm, respectively. Moreover, the repetition experimental results confirm that the desulfurization by sul folobas is steady.

Metal-polyvinyl alcohol (PVA) composite ultrafiltration membranes were prepared by coating a certain concentration of PVA solution on metallic fiber sintered membranes. The effects of preparation conditions, such as the coating solution concentration, sequence and times of coating, and heat-treatment on the properties of the composite membranes were studied. The results show that the hole diameter of the composite membrane decreases with the increases of the concentration of PVA, the hole diameter of composite membrane is different when the sequence of coating is different. When the higher concentration of PVA solution is used to coat the metallic membrane for the first time and the other smaller one for the second time, the hole diameter of the composite membrane is relatively small, compared with that of the composite membrane made by the smaller concentration of PVA solution for the first time and the other higher one for the second time. The holes of the composite membrane contract and the stability of the membrane is improved by heat treatment. When metal-PVA composite hydrophilic membranes are used to treat the oil/water emulsion with the concentration of 1000 mg·L⁻¹, the retention is from 80% to 90%, and the permeate flux is from 15 L·m⁻²·h⁻¹ to 40 L·m⁻²·h⁻¹ at pressure of 0.2 to 0.3 MPa.

The time course of xylo-oligosaccharides concentration and xylo-oligosaccharides yield in the separation of xylo-oligosaccharides from enzymatic hydrolytes was studied using a membrane reactor with constant permeate flux of 4 L · m⁻² · h⁻¹. The results show that xylanases retain 90% of its activity in the reactor. The concentration of xylo-oligosaccharides achieves the maximum, about 5.48 g/L in 30 min. The difference of xylo-oligosaccharides in the retentate and permeate stream is low, <0.62 g/L, therefore it can permeate through membrane. Under the operating conditions that xylan concentration is 30.0 g/L, pH 5.0, operating pressure 16 kPa, temperature 48 °C, feed velocity 400 mL/min, reaction volume 400 mL, enzyme dosage 10% (volume fraction), dilution rate 1 h⁻¹, and enzymatic hydrolysis time 195 min, the yield of xylo-oligosaccharides reaches 31.69%.

The electrochemistry behaviors of gold electrode in thiourea solution were studied by using electrochemical techniques, such as potentiodynamic, voltammogram and current step. A catalytical electrochemical-reduction mechanism was proposed to identify the anodic oxidation of gold in the thiourea solution. The results indicate that the decomposition of thiourea occurs when the electrode potential is higher than 640 mV. The addition of sulfurous acid presents a very positive effect on the anodic process of gold electrode. The anodic oxidation rate of gold is 5 times faster than that without sulfurous acid. The passivity of gold electrode is attributed to the accumulation of elemental sulfur on the surface of gold. The sulfurous acid reacts with the oxidation product (SC(NH)NH₂)₂) of thiourea, which can decrease the decomposition of thiourea and improves its stability.

An automatic monitoring technique of the seepage line, including the monitoring design, the automatic monitoring system and the backfill technique of the measuring probe of pore-water pressure, was used in a tailings dam, and a shallow refractive seismic method was investigated for obtaining the seepage line of those areas outside the monitoring zone. The results show that the automatic monitoring has the error within ±3% relative to piezometric tube method and improves monitoring efficiency greatly, and the shallow refractive seismic method has the error within ±10% but expands the area of monitoring. Both of them can be used for a daily measurement in monitoring the seepage line. The result of the automatic monitoring also shows that not only the design of the survey line and the backfill technique of the measuring probe of pore-water pressure are reasonable and economic but also the reliability and safety of the automatic monitoring system are better. Testing result by the shallow refractive seismic method in tailings reveals that the energy excited by hammering iron sheet-pole is strong enough and safe, and that the character of anti-jamming by the detectors with long tailcone is better.

Three fundamental problems in the calculation of train derailment abroad and at home were pointed out and the solutions to these problems were presented. The theory of random energy analysis for train derailment was suggested. The main contents of this theory are as follows: geometric criterion of derailment; method of random energy analysis of transverse vibration of train track system; mechanism of derailment and energy increment criterion for derailment evaluation; calculation of the entire derailment course of train. This theory is used to calculate a case of freight train derailment, which corresponds to an actually occurring accident. Another derailment test, in which the train is judged not to be derailed, is calculated and the maximum vibration response is well correspond to the test results. And the effectiveness and practicability of the theory are proved by the two calculated cases.

A new static task scheduling algorithm named edge-zeroing based on dynamic critical paths is proposed. The main ideas of the algorithm are as follows: firstly suppose that all of the tasks are in different clusters; secondly, select one of the critical paths of the partially clustered directed acyclic graph; thirdly, try to zero one of graph communication edges; fourthly, repeat above three processes until all edges are zeroed; finally, check the generated clusters to see if some of them can be further merged without increasing the parallel time. Comparisons of the previous algorithms with edge-zeroing based on dynamic critical paths show that the new algorithm has not only a low complexity but also a desired performance comparable or even better on average to much higher complexity heuristic algorithms.

Based on the idea of fusing modeling, an integrated prediction model for sintering process was proposed. A framework for sulfur content prediction was established, which integrated multi modeling ways together, including mathematical model combined with neural network(NN), rule model based on empirical knowledge and modelchoosing coordinator. Via metallurgic mechanism analysis and material balance computation, a mathematical model calculated the sulfur content in agglomerate by the material balance equation with some parameters predicted by NN method. In the other model, the relationship between sulfur content and key factors was described in the form of expert rules. The model-choosing coordinator based on fuzzy logic was introduced to decide the weight of result of each model according to process conditions. The model was tested by industrial application data and produced a relatively satisfactory prediction error. The model also preferably reflected the varying tendency of sulfur content in agglomerate as the evidence of its prediction performance.

An efficient QoS routing algorithm was proposed for multiple constrained path selection. Making use of efficient pruning policy, the algorithm reduces greatly the size of search space and the computing time. Although the proposed algorithm has exponential time complexity in the worst case, it can get the running results quickly in practical application. When the scale of network increases, the algorithm can efficiently control the size of search space by constraint conditions and prior queue. The results of simulation show that successful request ratio (r) of efficient algorithm for multi-constrained optimal path (EAMCOP) is better than that of heuristic algorithm for multi-constrained optimal path (H-MCOP), but average computing time (t) of EAMCOP is far less than that of H-MCOP. And it can be seen that the computing time of EAMCOP is only one fourth of that of H-MCOP in Advanced Research Projects Agency Network (ARPANet) topology.

To enhance the quality of grade 20 carbon-steel on the continuous casting production line, the mechanism of forming blowholes and non-metallic inclusions in billets and numerical simulation of flow phenomena about liquid steel in tundish were studied. The results show that the configuration and operation of tundish play an important part in quality assurance of grade 20 carbon-steel products. By optimizing the configuration of the tundish, the depth of liquid bath in tundish is enhanced, the impact of liquid steel is decreased, and the residence time of liquid steel is lengthened, which is useful for eliminating inclusions and blowholes and improving the service life of tundish. Improving the pouring and tapping operation of liquid steel can avoid the contact of liquid steel with air, and decrease re-oxidation. Strict control of the superheat degree of casting liquid steel can decrease the non-metallic inclusion content of the re-oxidation in billets and reduce the erosion of tundish. The inclusions and blowholes in the continuous casting grade 20 steel billets are reduced to a great extent and qualification rate is enhanced from 60% to 80%.

By using the connections between Brownian family with drift and elliptic differential equations, an efficient probabilistic computing method is given. This method is applied to a wide-range Dirichlet problem. Detail analysis and deduction of solving the problem are offered. The stochastic representation of the solution to the problem makes a 3-dimensional problem turned into a 2-dimensional problem. And an auxiliary ball is constructed. The strong Markov property and the joint distributions of the time and place of hitting spheres for Brownian family with drift are employed. Finally, good convergence of the numerical solution to the problem over domain with arbitrary boundary is obtained.