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It is well known that phase equilibria and phase diagrams can successfully guide the comprehensive utilization of the salt lake resources. The researches on phase chemistry and thermal chemistry of the calcium-containing brine system are essential to promote the development of brines. In this paper, the progresses on the phase chemistry and thermal chemistry of the calcium-containing brine system around the world from 2007 up to now were summarized. The problems existed and the new trends in the future were also carried out.

It is well known that the comprehensive utilization of salt lake resources can not only create a good economic benefit, but also effectively protect ecological environment of salt lake and achieve sustainable development. After potassium separating for potassium fertilizer from salt lakes, the rest of mother liquor brines are rich resources of magnesium and boron. Research on phase equilibria of salt-water systems containing magnesium and borate can provide reference data for comprehensive development and utilization of salt lake resources.

Salt lake brine resource is one of the strategic resources in the western of China. Phase equilibria and phase diagrams are the theoretic foundation for the exploitation of salt lake brine resources. Hence, studies for the stable and metastable phase equilibria of lithium-containing salt-water systems are of the great importance for the development of salt lake brine resources. In this paper, the stable and metastable phase equilibria of lithium-containing salt-water systems were summarized, and the problems existed at present and the new trends in the future are also discussed.

In this paper, the thermodynamic properties including the standard molar enthalpies of formation, the standard molar entropies of formation and the standard molar Gibbs free energy of formation of hydrated lithium borates and the water vapor pressures, the osmotic coefficients, the enthalpy of dilution, the molar heat capacity of aqueous lithium borate solution systems were summarized and the new trend in the future was also pointed out.

Sample pretreatment techniques for arsenic speciation analysis in biosamples are of significant importance in detection procedures. In this paper, several typical pretreatment techniques such as solvent extraction (SE), enzymatic hydrolysis (EH), pressurized liquid extraction (PLE), solid phase microextraction (SPME) and liquid phase microextraction (LPME) were summarized on the basis of 20 references. The new trend in the future was also carried out.

In this paper, the methods for rubidium (Rb) and cesium (Cs) recovery from brines including salt lake brine, geothermal water and concentrated seawater were summarized, and the main problems existed were also pointed out. More details for Rb and Cs recovery from salt lake brines through fractional precipitation, ion exchange and solvent extraction were discussed, and the new trend for Rb and Cs recovery in the future were also carried out.

As a kind of renewable clean energy, the constant access of wind power to power grids is bound to have a great impact on the power system. Based on the grid structure in Fuxin, this paper will state the difficulty of peak regulation and the matter of wasting wind power caused by the large-scale wind power integration and put forward some reasonable methods for using the wasting wind power in the heating in winter. The relevant results indicate that capacity of local consumption of wasting wind power can be improved. Under the circumstances, it can be conductive to solve the problem of wasting wind power results from the difficulty of peak regulation as well as inspire the power system planners.

Al-5Ti-1C master alloy refiner was prepared by melt reaction method, and its refining efficiency was examined by purity aluminum in the paper. The microstructures under different process conditions were studied by OM, SEM and XRD. The results shown that the grains were finer, TiAl3 and TiC phases were uniformly distributed at 900¡æ, held time for 15min. The refining efficiency was best at addition of 0.4% (wt.%) refiner and held time for 10min.

The creep characteristics of red layer sliding soil under the condition of different vertical loads and water contents were studied through a series of direct shear creep tests. Tests results showed that the water infiltrated to the sliding zone along the fissure of red layer sliding belt due to the crush of red layer sliding rock, leading to softening of sliding zone and acceleration of shear creep. When the shear stress reached the limit of long-term shear strength, sliding soil was broken suddenly with small vertical loads (50 kPa and 100kPa), while the sliding soil presented as a constant acceleration creep with enough vertical loads (200 kPa and 300 kPa). The inflection point in shear stress-shear displacement isochronous curve corresponded to the long-term strength of the soil.

In the paper, the progresses on the thermodynamic properties of several alkalis borates including lithium borates, sodium borates, potassium borates, rubidium borates and cesium borates at present were summarized, and the new trend in the future was also pointed out.

The combination of enlarged flow design and micro-genetic algorithm constitute a new optimization design method, which be applied to optimization design of low specific speed pump impeller. It improves enlarged flow design deficiencies, and making overall performance of the pump better. The experimental results of a low specific speed centrifugal pump impeller designed by proposed method show that pump high efficiency range is extended, the hump phenomenon is eliminated, and shaft power overload phenomenon has been resolved.

Ionic liquids (ILs) have been considered as successful alternative extraction solvents, especially, they have become potential replacements of volatile organic compound in the extraction of metal ions for the properties of negligible vapor pressure, nonflammability, high thermostability, etc. In this paper, ILs as environmental friendly solvents in liquid-liquid extractions of alkali and alkaline earth metal ions were summarized, the part of extraction phase compositions, extraction conditions and back extraction method were discussed, and the potency of applications of ILs in extraction and separation of metal ions were also commented.

It is well known that the magnesium borates are important materials in all fields. In this paper, the process on synthesis and thermodynamic properties of several hydrated magnesium borates including MgO·2B2O3·9H2O (hungchaoite), MgO·3B2O3·7.5H2O (mcallisterite), MgO·3B2O3·7H2O, 2MgO·3B2O3·17H2O, MgO·3B2O3·5H2O (aksaite) were summarized. The key problems existed and the new trends in the future were also carried out.

Combined with the contents of the study-PSS low-pass link parameter identification. Least-squares method is selected. Using least-square method for PSS low-pass link mathematical model are also deduced. For the results, because of the mathematical model is solving nonlinear equations, cannot used by the Newton method directly. So we choose to use Newton iterations, with this feature, choose to use MATLAB software to solve the equation. Identification of the use of MATLAB software lags after the PSS parameters obtained recognition results compared with national standards, identifying and verifying the practicability.

Tool path is usually described by means of continuous small linear segments. It results in large number of programming points in order to achieve high precision. A construction method of tool path based on arc-cell is presented in this paper, and the tool path is G1 continuous. The construction method is applied to describe the tool path of wave shape specimen and hill shape specimen. For the two specimens, when their tool paths are described based on continuous small segments, 128212 and 184954 linear segments are necessary, respectively. But when their tool paths are described based on arc-cell, 15838 and 21669 arc-cells are necessary, respectively. And its more important that these arc-cells include information of curvatures and arc-lengths to control acceleration and deceleration.

As peritectic steel is crack sensitive steel, peritectic-steel mold flux needs a higher performance requirement, In this paper, it is analyzed in detail that various properties of peritectic steel mold flux have effects on the quality of peritectic steel billet .

Lithium and its compounds are important materials in industry. In this paper, lithium recovery methods both from solid ores and brines were summarized, and the key problems existed were also pointed out. More details for lithium recovery from brines by solvent extraction, ion-exchange, precipitation and calcination leaching methods were discussed, and the new trend for lithium recovery in the future was also carried out.

It is well known that the exploitation of brine resources of salt lakes is based on the relevant phase equilibrium and phase diagrams. In this paper, the progresses on the stable and metastable equilibria, thermodynamic properties and predictive solubilities of the brine system containing lithium and borate ions at present were summarized. The problems existed and the new trends in the future were also carried out.

Solubilities of the reciprocal quaternary system (Li+, Mg2+//Cl-, SO42-–H2O) at 273.15K were calculated using Pitzer and its extended HW model. The values of the Pitzer single-salt parameters β(0), β(1), β(2)and Cφfor LiCl, MgCl2, Li2SO4, and MgSO4, the mixed ion-interaction parameters θLi,Mg, θCl,SO4, ψLi,Mg,Cl, ψLi,Mg,SO4, ψLi,Cl,SO4and ψMg,Cl,SO4, and the Debye–Hückel parameter Aφin the system at 273.15K were derived either temperature-dependent equation or through fitting solubility data of the ternary system by multiple linear regression method. Based on the Jänecke indexes, the phase diagram was plotted. This study affords the necessary parameters for solubility predictions of complicated systems and establishes a theoretical basis for the separation of these valuable minerals from salt lake brine.

Generally, along with the rapid economic development in our country, the requirement of mineral resource is gradually increasing. Compared with the traditional metallurgy, the biohydrometallurgy has the merit of light damage of environment, low cost, and a few investments, and then it can treat with very low-grade ores even industrial disposals. Since the discovery of scattered elemental tellurium deposit in China, the development and utilization of this unique independent tellurium ores were studied. In this paper, firstly, the progresses on tellurium recovery process from the unique tellurium ores were summarized, and then, the experimental results on bioleaching in our lab were presented.

In this paper, the processes on boron recovery from the liquid mineral resources (salt lake brine, oil- or gas-field water, and concentrate seawater) including the processes of precipitation, solvent extraction, fractional crystallization, ion exchange, and combined method at present were summarized, and the new trend in the future was also pointed out.

Energy demand to ensure a comfortable environment for humans has increased worldwide, especially in the application of phase change material (PCM) for resident living. In this paper, the current applications of PCMs including solar water-heating system, solar cooker and residential building aspects were presented, and the suggestions for future works were also discussed.

The photonic crystal which can perform total reflection for a range of frequencies of light can be used as thermal control coating, optical fiber and optical filter. The prediction and characterization of mechanical properties are crucial to improve the processing methods and optimize the structure of the films in order to sustain mechanical stresses. In terms of modeling and prediction of the mechanical properties, this work presents a finite element model for a photonic crystal film indented by a perfectly rigid sphere. In addition, the numerical solution is compared to the experimental results obtained by nanoindentation and shown a good correlation. The effect of the contact depth on the mechanical properties was also provided.

Solar-coal complementary electric generation is a new way to utilize solar thermal, however, using solar thermal to replace the heat transfer of some heating surfaces will inevitably affects the stability and efficiency of boiler operation, and the running characteristics of the boiler will affects the utilization capacity of the solar thermal in turn. A 300MW unit thermal- circulation boiler has been studied. A research on calculation of heat transfer characteristic has been made. The influence of solar-energy utilization on heat transfer has been analyzed. Calculation and analysis indicate that using solar thermal to heat the feedwater can decrease coal consumption. 87.2% of the coal consumption decrement can be attributed to the replacement of coal by solar thermal, 12.8% of the coal consumption decrement is leaded by the boiler efficiency increment; Solar thermal should not be introduced into the boilers with low exhaust gas temperature and the boilers running at low load operation; Using solar thermal to heat the feedwater leads to decreasing spray water; Through the boiler calculation in this paper, the maximum solar thermal utilization capacity is 19.27MW.

This study was designed to investigate tellurium bioleaching from the unique independent low-grade tellurium ores containing tetradymite, joseite, pyrite, chalcopyrite, silica, and a minor amount of dolomite, which is the first discovered scattered element deposit in the world. For the bioleaching, the tellurium extractions from the low-grade ores by with and without the adapted bacteria of acidophilic Thiobacillus ferrooxidans were examined. The effects of pH, pulp density, and temperature for bioleaching were studied systematically. After 20 days of bioleaching at 30°C, an 80 % of the tellurium was extracted in laboratory study. Leaching kinetics indicated that diffusion through the product layer was the rate controlling process during tellurium bioleaching, and the relative activation energies during tellurium bioleaching stage was calculated to be 34.75 kJ/mol.

Electricity transformer is an important, widely used electrical equipment. Current the iron beam sectional of the electricity transformer is based on experienced standards which can not achieve the best economic benefits. According to practical technology, we build a basic optimization model about multistep iron beam section. And we also give a reasonable design on the tolerance zone between the diameter of iron beam sectional circumcircle and the diameter of the winding steel-flue, as well as the arrangement about the oil path in the iron beam, which has a big realistic significance and application value. We come up with five reasonable model assumptions to simplified the problem, turning the tolerance zone design problem into the function extreme one. We adopt "Ideal assumption first, specific modification second" method on designing the oil path, considering all kinds of situations to obtain optimization. The core algorithm is dynamic programming which is much faster, much more stable than using Lingo. All the solving and analyzing on math models are based on C++ programming language.

Activated carbon-supported platinum was prepared and characterized by fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), respectively. And the hydrosilylation of allyl glycidyl ether with trimethoxysilane catalyzed by platinum on activated carbon was discussed. The effects of reaction temperature, reaction time, feeding fashion and mixture ratio of precursors on the Pt/C catalytic this hydrosilylation were also investigated. The results showed that the reaction can generate the product of 3-glycidoxypropyltrimethoxysilane at an efficiency of as high as 97.4% under the optimal conditions.

The compact storage and efficient evaluation of feasible assembly sequences is one crucial concern for assembly sequence planning. The implicitly symbolic ordered binary decision diagram (OBDD) representation and manipulation technique has been a promising way. In this paper, Sharafat’s recursive contraction algorithm and cut-set decomposition method are symbolically implemented, and a novel symbolic algorithm for generating mechanical assembly sequences is presented using OBDD formulations of liaison graph and translation function. The algorithm has the following main procedures: choosing any one of vertices in the liaison graph G as seed vertex and scanning all connected subgraphs containing seed vertex by breadth first search; transforming the problem of enumerating all cut-sets in liaison graph into the problem of generating all the partitions: two subsets V1and V2of a set of vertices V where both the induced graph of vertices V1and V2are connected; checking the geometrical feasibility for each cut-set. Some applicable experiments show that the novel algorithm can generate feasible assembly sequences correctly and completely.

In Section 1, we describe process of ball-bat collision using kinetic model, and derive the post-collision ball speed as a function of the hitting location. Then we differentiate the function and find out where the sweet spot is. The result successfully explains the best location is not at the end of the bat in consistent with our practical experience. In Section 2, based on the model in Section 1, we add two assumptions, supposing corking only influences mass and moment of inertia of bat. Then the maximum outgoing ball speed is only depended on mass of bat. The result shows properly corking will enhance the bat performance. In Section 3, we explain “trampoline effect” in dynamic model and throw light on energy transformation in collision process. We conclude that COR is related to materials, and aluminum bats perform better than wood bats.

Algorithms based on timed Petri net are competitive for solving the problem of assembly sequence planning (ASP). In order to alleviate the state-space explosion problem which is caused by the Petri net-based representation of assembly sequences and to improve the efficiency of planning algorithms, an approach based on ordinary binary decision diagrams (OBDDs) is presented in this paper. On the one hand, all the timed transitions in Petri nets are substituted by some technically designed timed transition structures; on the other hand, Petri nets used in algorithms of assembly sequence planning are represented symbolically as OBDDs. As a result, a novel assembly sequence planning algorithm based on symbolic OBDDs is presented. With the help of OBDDs, both the marking vectors and the states of Petri nets are formulated more compactly; at the same time, the searching processes can be manipulated implicitly. Therefore, compared with original algorithms, both the time performance and the space performance are improved.