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Solid-state high-resolution13C/7Li nuclear magnetic resonance (NMR) study was performed on the phase structure and chain dynamics of PEG-PPG-PEGn/LiCF3SO3(n=3, 6, 12) copolymer electrolytes. PEG repeating units and Li+form PEG3:LiCF3SO3crystalline complex and PE3/Li+amorphous complex in all the samples. PPG repeating units and Li+form different complexes with respect to O:Li+feed ratio (denoted as PP/Li+-3/6/12). The13C chemical shifts and half widths of the signals from PP/Li+-3/6/12 remain unchanged, which implies the structures of PP/Li+-3/6/12 are similar at least in a very short range. The half width of the7Li signals from PP/Li+-3/6/12 becomes narrower and narrower as the Li+concentration decreases. This indicates the chain mobility of the amorphous phase increases with the decrease of ionic concentration. Moreover, neat crystalline PEG, neat amorphous PEG and neat amorphous PPG start to appear when O:Li+is greater than 3:1 and their contents increase with the increase of O:Li+. Overall, solid-state high-resolution NMR is a powerful and unique method for understanding the phase structure and chain dynamics of solid polymer electrolytes (SPEs), more applications of this technique to studies on SPEs is expecting.

Query recommendation as an important tool to enhance the user search efficiency has gradually become a hotspot. In the context of big data, using the MapReduce programming model, combined with distributed minimum spanning tree algorithm, a parallel query recommended method based on MapReduce was proposed in this paper. The final results show that the efficiency of query recommendation was greatly improved through parallel computing.

Active carbon and sodium silicate were produced simultaneously from pyrolyzed rice husk (PRH) by CO2 activation coupled with NaOH solution boiling. Doehlert matrix and Derringer's desirability function were applied to optimizing the boiling conditions to achieve a large specific surface area, a high silica extraction and low alkali consumption. In terms of this purpose, the optimum condition was determined as boiling CO2-activated char with 1mol/L NaOH solution at a liquid/solid ratio of 9.7 mL/g. Under this condition, the modulus of the sodium silicate and the specific surface area (SSA) of the active carbon were 2.62 and 897 m2/g, respectively. The values both reached their respective commercial levels. The pretreatment of the PRH with CO2 activation can markedly increase the SSA of active carbons.

To solve the problem of the time sequential synchronization of semi-physical simulation on some guidance weapon system, we proposed a method of zero time alignment and simulation time adjustment. The simulation results indicate the strategy of synchronization is feasible, and the time sequential of the semi-physical simulation is correct. (2013) Trans Tech Publications, Switzerland.

Highly mesoporous active carbon for removing methylene blue (MB) from aqueous solution was prepared from pyrolyzed rice husk by combination of CO2activation and NaOH-solution boiling. The preparation method was found to be alkali-saving and equipment-friendly. The prepared active carbon exhibited high mesoporosity (79.1%), with mesopore volume and specific surface area up to 0.619 mL/g and 899 m2/g, respectively. At initial MB concentrations of 240-380 mg/L, the MB removal efficiency of the prepared active carbon ranged from 92% to more than 99%, fairly comparable to that of the highly mesoporous commercial active carbon used for reference. The adsorption of MB onto the prepared active carbon well followed the pseudo second-order kinetic model and Langmuir isotherm. This study indicated that highly mesoporous active carbon with large dye removal efficiency could be prepared from rice husk by an alkali-saving and equipment-friendly process.

This paper presents a method of computing the boundary of the landing location of vehicle on reentry mission. By transforming the inequality constraints into the boundary in energy-drag space, the drag profile can be scheduled with respect to the normalized energy between the upper and lower bound which leads to the near edge and far edge of the landing zone. The magnitude of the bank angle can be derived from the drag profile, while the cross-range can be adjusted by modifying the sign of bank angle. With the derived magnitude and sign of bank angle, thestate equation can be solved to generate the landing zone.

Due to the complex structure of the rolling bearing, a simplified bearing model was founded and then thermal stress simulation was analyzed with ANSYS. The various parts of the displacement changes can be got. Compared the simulation results with the actual results, it can be drawn that the simulation result is basically same with the analytical result. So the simplified model is right. This method is simple, and can be adapted to the general clearance analysis.

This paper presents a parametric optimization approach to solve reentry guidance. Due to the various constraints imposed on the trajectory, original guidance problem can be converted into an optimal control problem with a merit function to be minimized. Direct implementation of method of variation and is too complex to get a reasonable result, while a numerical parametric optimization approach is feasible and efficient if we choose appropriate control variables as the optimization parameters and effective optimization algorithm. A simulation of the approach is performed to show its validity on reentry guidance problem: as the value of merit function converges to acceptable threshold, all constraints are hold. (2013) Trans Tech Publications, Switzerland.

Vehicular ad-hoc Networks (VANETs) has become a hot topic in recent years, where the routing protocol has also become research focus. The vast majority of the existing routing protocols are designed for a single scenario, thus it is difficult for them to be extended for the complicated traffic environment. In this paper we propose a new routing algorithm X-CAST for vehicular communication on highway, which can be adaptive to different phases of traffic flow and guarantee reliable transmission in different environments. The experimental results reveal that X-CAST performs much better than other traditional routing protocols in complex traffic flow situation.

The performance of the rotor of the electric eddy current dynamometer has a great influence on the capability of the dynamometer. The stiffness and damping of the rotor can be obtained by analyzing its motion equation. And the critical speed can be achieved by getting the natural frequency and the vibration through ADAMS based on the theory of flexibility. Based on the machine design handbook, some proofs were provided by the conclusion that the speed of the rotor should be the range of the different critical speed of the modal in order to assure the safety and high efficiency of the dynamometer. Focused on the need for the design of the rotor, this method which solves the difficulties of the intensive calculation in the design and optimization of the dynamometer’s rotor is exact and effective.

The increasing complexity of construction projects as a common trend has had a significant impact on management maturity assessment and improvement for the project participating units, especially for the owners’ Project Management Office (PMO). While most maturity models are rationalistic, this paper presents a practical complex construction project management maturity model based on project management three-dimensional perspective. Integrating Organizational Project Management Maturity Model (OPM3) and Best Practices (BPs) derived from 2010 Shanghai Expo practice, this case-based maturity model is constituted by three sub-models: PBS Maturity, Process Maturity and Organization System Maturity. The model uses structured questionnaire consisting of BPs to implement assessment. The proportion of BPs achieved is considered as the maturity level of assessment objectives. Shanghai Expo AB Area is used to test the validity of the model. The result shows that owners’ PMO can assess and improve their project management maturity with the model effectively.

Pepper (Capsicum annuum L) is an important economic vegetable crop in worldwide, however the pepper blight caused by Phytophthora capsici has been epidemic in many countries. Little is known about pepper–oomycete interactions at the molecular and genetic levels. The objective of this study was to identify transcriptionally regulated genes during an incompatible interaction between pepper and P.capsici using cDNA-AFLP technique. A total of 100 transcript-derived fragments (TDFs) were sequenced. The result revealed that 84 (88.0%) TDFs produced specific sequences, among which 19 TDFs had relatively clear functions in various categories. Seven TDFs (9.5%) shared high similarities with defense- or stress-related proteins. The TDFs identified in this study will serve as candidates for further studies to determine their functions and dissect the molecular networks involved in the pepper- P.capsici interactions.

Porous FeAl intermetallics were produced by high-energy ball milled Fe-Al binary composite powders followed by sintering. The microstructure evolution of milled Fe-Al composite powders during high-energy milling processing were observed and analyzed using SEM and XRD. FeAl intermetallics was synthesized by sintering at 1200°C for 4h with a pre-sintering at 620°C. The microstructure of the sinters was also investigated. XRD results and SEM images showed that milling time and sintering temperature accelerated the formation of FeAl intermetallics. The microstructure of the milled sinter apparently improved the properties of FeAl intermetallics.

The chemical oxidation of p-cymene was preliminarily studied by several oxidants. The conversion of p-cymene and selectivity of p-cymen-8-ol were both influenced by the factors such as dosage of oxidant, dosage of sulphuric acid, reaction time, reaction temperature and solvent variety. The reasonable oxidation conditions were molar ratio of p-cymene to potassium permanganate 1:3, molar ratio of sulphuric acid to potassium permanganate 0.13:1, mixture of water and acetic acid (1:1, v/v) as solvent, reaction temperature 80 °C and reaction time 9 h. The conversion of p-cymene and selectivity of p-cymen-8-ol were respectively 92.21 % and 69.65 % in the reasonable oxidation conditions. The by-products of p-cymene oxidation mainly included p-iso-propyl benzoic acid, p-isopropyl benzaldehyde and p-methyl acetophenone.

A study to track and detect the variation of bioactive components in rosemary extraction solution and extracts, by adding organic acid synergists, such as citric acid, oxalic acid and tartaric acid, was performed using high performance liquid chromatography (HPLC). Ultrasound was also used to increase the extraction efficiency, improve the yields of rosemary extracts and shorten the extraction time. The experimental results showed that the content of the key bioactive component carnosic acid was easier to reduce during the storage of extraction solution and extracts, meanwhile, adding citric acid, oxalic acid and tartaric acid during the extraction could actually slow down the trend of the reduction of the bioactive components, especially for carnosic acid.

An efficient numerical technique, namely the Local Monte Carlo Simulation method, is presented to assess the reliability sensitivity in this paper. Firstly some samples are obtained by the random sampling, then the local domain with a constant probability content corresponding to each sample point can be defined, finally the conditional reliability and reliability sensitivity corresponding to every local region can be calculated by using linear approximation of the limit state function. The reliability and reliability sensitivity can be estimated by the expectation of all the conditional reliability and reliability sensitivity. Three examples testify the applicability, validity and accuracy of the proposed method. The results computed by the Local Monte Carlo Simulation method and the Monte Carlo method are compared, which demonstrates that, without losing precision, the computational cost by the former method is much less than the later.

The variation regulation of five bioactive components including carnosic acid (CA), carnosol (CO), rosmarinic acid (RA), oleanolic acid (OA) and ursolic acid (UA) in rosemary leaves and extraction procedure was studied. The effects of rosemary sources, steam distillation time, activated carbon dosage and storage time of extraction solution on variation regulation of bioactive components were discussed in detail.

Turpentine-based dipentene (TBDP) contains limonene 30.32 %, terpinolene 31.35 %,α-terpinene 7.55 %,γ-terpinene 6.40 % andp-cymene 12.87 %. Three Pd/C catalysts were characterized by BET, XRD, TG-DTG and atomic absorption spectrometry (AAS). The properties of the catalysts on TBDP conversion were compared. Difference of catalytic competitive reactions of TBDP by catalyst A with the change of reaction temperature was discussed in detail. The yield ofp-cymene at 280-310°C was over 95.0 %. It was important to control the reaction temperature for TBDP dehydrogenation catalyzed by Pd/C catalysts. It is valuable to probe the catalytic behaviors of Pd/C catalyst on TBDP dehydrogenation for research and development of efficient preparation technology ofp-cymene from TBDP.

Wireless Sensor Networks (WSNs) enable susceptible sensing of the environment, offering unprecedented opportunities for observing the physical world. Acoustic source localization is an interesting topic with many possible application areas, such as intruder detection, sniper localization, automatic tracking of speakers and so on. Many existing algorithms are on the premise that the exact coordinates of sensor nodes are already known. In this paper, we propose a vector-based advanced TDoA algorithm that would calibrate the coordinate of the acoustic source by the non-prepositioned nodes. In the meanwhile, the portable sensor nodes would adjust themselves through the feedback of the estimated positions as well. Finally, we show that the proposed mechanism has high accuracy through experiments.