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Ultrathin conversion coatings, made from aligned graphene derivatives and ammonium zirconium carbonate (AZC), were fabricated on stainless steel by electrodeposition. Sulfonated graphene oxide (SGO) provided electron pathways and physical barriers to corrosive molecules. Electrodeposition ensured the alignment of SGO and the facile fabrication of the coatings. AZC is an environmental-friendly crosslinking agent, water-repellent and corrosion inhibitor. Upon dehydration reactions, AZC improved the cohesion between SGO layers and anchored the conversion coatings on metal substrates. When the mass ratio of SGO to AZC was 2:1, the corrosion current density of the composite coatings reached 0.098 ​μA ​cm−2, while that of the bared stainless steel was 1.04 ​μA ​cm−2, given a coating thickness of only 500 ​nm. The electrical conductivity of SGO/AZC composite coatings can be tailored from 3.84 ​× ​10−5 to 2.28 ​× ​10−3 ​S‧cm−1 by heat treatment and HI reduction, which satisfied the electrical conductivity requirement of wide applications in electronic industry, office appliances and petroleum storage.

The physicochemical characteristics and pyrolysis performance of corn stalk (CS) torrefied in water and aqueous ammonia by microwave heating were investigated. Physicochemical characterization revealed that both microwave water torrefied CS (MCS) and microwave ammonia torrefied CS (MACS) showed low hemicellulose content, disrupted macrostructure, improved porous properties, and low ash content. MACS exhibited a significantly lower crystallinity degree of 44.34% than CS (79.55%) and MCS (89.50%). MACS also showed increased methyl/methylene groups intensity, and complete acetyl groups disrupture. Pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS) revealed that compared with CS and MCS, MACS exhibited higher peak areas for ketones, aldehydes, furans and esters, and significantly lower peak areas for acids and phenols. A possible mechanism was proposed for the effects of wet torrefaction with aqueous ammonia on changes in physicochemical structure and pyrolysis behavior of corn stalk.

This study explores a new electroplating wastewater treatment process which could be cheaper and more efficient than the conventional approaches. The process consists of 3 steps: (1) electric lime is added to the electroplating wastewater to adjust the pH to around 9; (2) activated carbon is added to the turbid liquid; and (3) vacuum filter is used to replace traditional sedimentation tank for solid–liquid separation. Electric lime is used to replace liquid alkali for pH adjustment, which can greatly reduce production cost. Compared with the traditional sedimentation tank, the vacuum filter occupies less space, has lower operating cost and higher filtration speed, which greatly improves the production efficiency. The effluent of treated electroplating wastewater using the new process has the COD content reduced by about 60%, and the total oil content reduced by about 80%. This is obviously better than the traditional treatment process.

Electroless nickel plating technology is also called chemical nickel plating, which is an important nickel plating method. However, the wastewater produced by electroless nickel plating contains a large amount of phosphorus and nickel. The heavy metal nickel is carcinogenic and has sensitizing effects. It is also toxic to environmental organisms. Phosphorus is a well-known factor that leads to eutrophication of water bodies. How to effectively deal with the waste solution of chemical nickel plating, turning the environmental pollutants into recyclable resources, and reducing the damage to the ecological environment are of great significance. This article applies ozone to the treatment of nickel wastewater. Its success brings the possibility of developing a new method for the treatment of nickel wastewater.

Copper was widely used in electroplating, and a lot of wastewater was produced in the rinsing process. Copper-containing electroplating wastewater can be divided into cyanide wastewater and copper sulfate wastewater according to the difference of plating process. This study is to explore the feasibility of cyanide oxidation and cupric reduction in an electrochemical reactor using an anion exchange membrane as the diaphragm. In the anolyte compartment cyanide in the cyanide wastewater was oxidized to cyanate, and furthermore, to carbon dioxide and nitrogen. In the catholyte compartment cupric in the copper sulphate wastewater was restored to copper. This study showed that the dosage of sodium hypochlorite used in the cyanide oxidation was decreased from 95 to 15 g/L and over 80% copper was recovered from copper sulphate wastewater by electrolysis.

The electroplating industry is one of the surface treatment industries with strong versatility and a wide application range. The electroplating process mainly includes pretreatment, electroplating, and post-treatment. In order to achieve specific effects, additives such as brightener, subbrightener, surfactant, and others are indispensable in the electroplating process. These organics usually have poor biodegradability. In addition, due to the high toxicity of electroplating wastewater, biological treatment has great limitations on their decomposition. These organic compounds cause the increase of COD in electroplating wastewater, which seriously pollutes the membrane system and hinders the development of electroplating wastewater reuse process. In this study, ozone is investigated for the oxidation of organics and the results are discussed.

Some biological experiments show that the tubular structures of Physarum polycephalum are often analogous to those of Steiner trees. Therefore, the emerging Physarum-inspired Algorithms (PAs) have the potential of computing Steiner trees. In this paper, we propose two PAs to solve the Steiner Tree Problem in Graphs (STPG). We apply some widely-used artificial and real-world VLSI design instances to evaluate the performance of our PAs. The experimental results show that: 1) for instances with hundreds of vertices, our first PA can find feasible solutions with an average error of 0.19%, while the Genetic Algorithm (GA), the Discrete Particle Swarm Optimization (DPSO) algorithm and a widely-used Steiner tree approximation algorithm: the Shortest Path Heuristic (SPH) algorithm can only find feasible solutions with an average error above 4.96%; and 2) for larger instances with up to tens of thousands of vertices, where our first PA, GA and DPSO are too slow to be used, our second PA can find feasible solutions with an average error of 3.69%, while SPH can only find feasible solutions with an average error of 6.42%. These experimental results indicate that PAs can compute Steiner trees, and it may be preferable to apply our PAs to solve STPG in some cases.

Using isopropanol as an in situ hydrogen donor, catalytic transfer hydrogenolysis of lignin into monomeric phenols was studied at mild conditions. The performance of catalysts and the effects of H2, temperature, and time on depolymerization of acid extracted birch lignin (ABL) were extensively examined. Platinum-rhenium supported on titanium dioxide (PtRe/TiO2) exhibited much higher activity on disrupting C O bonds than Pd/C, HZSM-5, Pt/TiO2, and Re/TiO2. 18.71 wt% monophenols was achieved for depolymerization of ABL over PtRe/TiO2 at 240 °C for 12 h with He. 4-Propylsyringol had the highest yield of 7.48 wt%. 2D HSQC NMR analysis reveals that β-O-4 bonds have been fully disrupted during depolymerization. Addition of H2 led to less monophenols, likely due to the competitive adsorption of active sites on catalysts. Structure-reactivity analysis based on six representative lignins shows that the total yields of monophenols were highly linearly correlated with the β-O-4 contents (R2 = 0.97).

Aiming at alleviating the adverse effects on attached microalgae biofilm growth caused by heterogeneous spatial light distributions within the attached cultivation photobioreactors (PBRs), an innovative PBR integrated with stacked horizontal planar waveguide modules (SHPW-PBR) was proposed in this work. Different from the conventional PBR, the emergent light from the external LED light bars were guided and evenly redistributed within the SHPW-PBR by the planar waveguides and hence provided light energy for microalgae cells photoautotrophic growth. In comparison with the control PBR, the average light intensity illuminating the attached Chlorella vulgaris biofilm in the SHPW-PBR was elevated by 204.11% and contributed to a 145.20% improvement on areal C. vulgaris biofilm production. Thereafter, responses of attached C. vulgaris biofilm growth in the SHPW-PBR to various light intensities were evaluated and the maximum areal C. vulgaris biofilm density reached 90.43 g m−2 under the light intensity of 136 μmol m−2 s−1 after 9 days cultivation. Furthermore, the SHPW-PBR can be easily scaled-up by increasing the quantity of the stacked planar waveguide modules and thus shows great potential in biofilm-based biomass production.

Star sensor's image plane can have three kinds of displacement after a long time working in space, and the displacements are the principal point drift, incline displacement and rotation displacement. These displacements can severely decrease star sensor's measuring accuracy, therefore it's necessary to analyze and calibrate them. The previous researches have only considered the principal point drift of image plane, which is three-degree-of-freedom. In contrast, the image plane displacements under the rest three degrees of freedom, that are the incline displacement and the rotation displacement, have been modeled in this paper. These two kinds of displacement's influences on star sensor's accuracy have been analyzed. And the necessity to calibrate them has been pointed out. At last, the Extended Kalman Filter has been used to on-orbit calibrate the six-degree-of-freedom image plane displacement. And the simulation results reveal that the on-orbit calibration algorithm can effectively calibrate the image plane displacement of star sensor. The measuring accuracy of star sensor has been increased to 0.23'' after the calibration. Therefore the new six-degree-of-freedom image plane displacement model has made up the deficiency of the conventional displacement model and enhance the performance of star sensor greatly.

Magnesium has been intensively investigated as a promising hydrogen storage material owing to its high storage capacity (7.6 mass%, 110 g L-1), good reversibility and relatively mild operating conditions. Research has been focusing on improving the thermodynamics and kinetics towards practical application via alloying, catalysis and nanosizing. Various synthetic approaches have been developed. In this thesis, investigation was conducted regarding the design and synthesis of magnesium nanomaterials based on the defined research gap. Furthermore, an alternative solution (i.e. light-activated hydrogen storage) has been validated, providing higher potential towards practical application. Initially, basic synthetic methods for magnesium were established, with the identification of the effects of synthetic parameters on the physical properties of the materials. The poor linkage between the particle size/morphology and the hydrogen storage properties suggests the necessity of further reducing the particle size for significant hydrogen storage property improvement. Nanosizing through the introduction of surfactants and matrix/support materials was implemented. Mg nanoparticles of 2-20 nm were obtained in various cases with universally observed hydrogen storage property improvement. However, when stabilised by surfactant (i.e. 1-dodecanethiol), the nanoparticles showed poor stability at elevated temperature. In contrast, superior stability was achieved for magnesium nanoparticles supported on nickel nanobelt and naphthalocyanine (TTBNc), which meanwhile showed higher magnesium loading efficiency as compared to the conventional carbon materials. Significantly improved thermodynamics (H < 53 kJ mol-1 H2) and kinetics (Ea < 70 kJ mol-1 H2) were observed coupling the nanosizing effect and interface interaction. However, the properties of the material still do not fulfil the requirements for practical application, mainly low capacity and still relatively high temperature (~200 C). To avoid the common problems for nanosizing, light-activated hydrogen storage was tested as an alternative solution. The feasibility and universality were proven by the phase transition observed for various hydrides. Further research work is still required to improve the effectiveness of light activation. The research carried out in this thesis provides novel approaches for the design and synthesis of a hydrogen storage system. Through a combination of different solutions (i.e. catalysis, nanosizing and light activation), there is higher potential leading to practical and wide application.

The Steiner tree problems are well-known NP-hard problems that have diverse applications. Duin et al. (2004) have intuitively proposed the widely-used transformation from the classical group Steiner tree problem to the classical Steiner tree problem in graphs. This transformation has not been rigorously proven so far. Specifically, the large M value that is used in this transformation has not been specified. In this paper, we address this issue by rigorously prove this transformation for a specific large M value.

The popular Physarum-inspired Algorithms (PAs) have the potential to solve challenging network optimization problems. However, the existing researches on PAs are still immature and far from being fully recognized. A major reason is that these researches have not been well organized so far. In this paper, we aim to address this issue. First, we introduce Physarum and its intelligence from the biological perspective. Then, we summarize and group four types of Physarum-inspired networking models. After that, we analyze the network optimization problems and applications that have been challenged by PAs based on these models. Ultimately, we discuss the existing researches on PAs and identify two fundamental questions: 1) What are the characteristics of Physarum networks? 2) Why can Physarum solve some network optimization problems? Answering these two questions is essential to the future development of Physarum-inspired network optimization., Comment: Physarum polycephalum; nature-inspired algorithm; data analytics

To reveal the influence of interactions between biomass components on physicochemical characteristics of char, biomass components (cellulose, xylan, and lignin), component mixtures and real biomass (maple) were pyrolyzed in a fixed-bed reactor. The morphology, elements contents, crystallinity, porosity characteristics, and functional groups distribution of the solid chars were systematically analyzed. Comparisons of the experimental physicochemical characteristics with the predicted values reveal apparent interactions within the components in the formation of char. The mixture of xylan-lignin (X-L) showed the most significant interactions. Interactions resulted in lower yields and better porosity development for all chars. Chars from the mixtures of cellulose-xylan (C-X) and cellulose-lignin (C-L) showed higher crystallinity and less hydroxyl groups than predicted, while char from the mixture of X-L presented lower crystallinity and less C O bonds than predicted. Maple exhibited stronger interactions than the synthesized ternary mixture. A possible mechanism of interactions between biomass components have been provided focusing on the formation of char.

A hyperbranched conjugated Schiff base polymer network was synthesized by condensation between 4,4',4''-nitrilotribenzaldehyde and p-phenylenediamine. The material exhibits excellent rate capability and long cycle life for lithium storage. Coupled with lower electrode potential (0.7 V vs. Li(+)/Li), it may be well suited for fully flexible thin film polymeric batteries as the negative electrode.

Along with the comprehensive advancement of education informationization, knowledge management (PM) is also researched unceasingly in the educational technology, it becomes a hot topic of discussion in this domain that how to gain, use, management and innovate effectively knowledge. The teacher and the student who are two big communities in the education domain are the centre of attention in personal knowledge management. At present, the harvest of personal knowledge management research is hardly abundance at home and abroad. The relevant theoretical systems are needed to be improved. Especially the personal knowledge management (PKM) for the student is the condition of starting. The theory of the personal knowledge management for the student and system's development, which are mainly discussed in this thesis, have important practical significance and application value.

This paper uses the content analytic method to analysis the articles about Knowledge Management in the main periodicals in educational technology, through analyzing a lot of date was regulated, based on that we can conclude research and development trend Knowledge Management in educational technology, and some advice about value actualization of Knowledge Management in is given.

Rapid development of computer, network and multimedia technology, has contributed to the pace of educational reform, design the multimedia teaching system based on .NET for the problems in teaching, expound the six functions and key technologies of the system.