摘要：The non-uniform concentrated solar flux distribution on the outer surface of the absorber tube can lead to large circumferential temperature difference and high local temperature of the absorber tube wall,which is one of the primary causes of parabolic trough solar receiver(PTR)*** this paper,a secondary reflector used as a homogenizing reflector(HR)in a conventional parabolic trough solar collector(PTSC)was recommended to homogenize the solar flux distribution and thus increase the reliability of the *** design method of this new type PTSC with a HR was also ***,the concentrated solar flux distribution was calculated by adopting the Monte Carlo ray-trace(MCRT)***,the coupled heat transfer process within the PTR was simulated by treating the solar flux calculated by the MCRT method as the heat flux boundary condition for the finite volume method *** solar flux distribution on the outer surface of the absorber tube,the temperature field of the absorber tube wall,and the collector efficiency were analyzed in *** was revealed that the absorber tube could almost be heated uniformly in the PTSC with a *** a result,the circumferential temperature difference and the maximum temperature could be reduced significantly,while the efficiency tended to decrease slightly due to the inevitably increased optical *** the conditions studied in this paper,although the collector efficiency decreased by about 4%,the circumferential temperature difference was reduced from about 25 to 3 K and the maximum temperature was reduced from667 to 661 K.

摘要：Central composite design(CCD),together with multiple linear regression,was successfully used to optimize the electrophoretic buffer system of micellar electrokinetic capillary chromatography(MEKC) for the determination of albiflorin,paeoniflorin,liquiritin,and glycyrrhizic acid in the traditional Chinese medicine(TCM) prescription,Yangwei *** of sodium deoxycholate(SDC) and borate,and proportions of ammonia,acetonitrile,and methanol were *** total resolutions of peaks between the analytes and their adjacent peaks in real samples were integrated into the evaluation index of separation *** optimum electrophoretic buffer contained 80 mmol/L SDC,20 mmol/L borate,5%(v/v) methanol,0.5%(v/v) ammonia,and 5%(v/v) *** correlation coefficients(R 2 ) between the peak areas and the corresponding concentrations of analytes were greater than *** limits of detection(LODs) (S/N=3) of the analytes were 0.97-4.00μg/*** results indicate the superiority of CCD in optimizing the separation conditions of complex samples such as TCM prescriptions.

摘要：Seven distributors with different configurations are designed and optimized by constructal approach. Their flow distribution performance and energy dissipation are investigated and compared by computational fluid dynamics （CFD） simulation. The reliability of CFD simulation is verified by experiments on the distributor that has all distributing rectangle channels on a plate. The results show that the symmetry of the distributing channels has decisive influence on the performance of flow distribution. Increasing the generations of channel branching will improve the flow distribution uniformity, but on the other hand increase the energy dissipation. Among all the seven constructal distributors, the distributor that has dichotomy configuration, Y-type junctions and straight interconnecting channels, is recommended for its better flow distribution performance and less energy dissipation.

摘要：This paper is concerned with the reliable H∞ filtering problem against sensor failures for a class of discrete-time systems with sector-bounded nonlinearities. The resulting design is that the filtering error system is asymptotically stable and meets the prescribed H∞ norm constraint in normal case as well as in sensor failure case. Sufficient conditions for the existence of the filter are obtained by using appropriate Lyapunov functional and linear matrix inequality (LMI) ***, in order to reduce the design conservativeness and get better performance, we adopt the slack variable method to realize the decoupling between the Lyapunov matrices and the system dynamic matrices. A numerical example is provided to demonstrate the effectiveness of the proposed designs.

摘要：Carbonyl compounds with elements of C, H, and O and reversible redox-active centers are promising elec- trode materials in rechargeable batteries owing to their high theoretical capacity, structure flexibility and resources abun- dance. However, the low conductivity and the dissolution of active molecules in organic electrolyte limit the practical ap- plication. Immobilizing the carbonyls on graphene provides a simple approach to address these two issues. However, most reported interaction between carbon-based substrates and carbonyl compounds is weak π-π interaction, which is not strong enough to prohibit the detachment of active ma- terials from carbon surface, and thus leading to undesirable cycling performance. Herein, we applied the first principle calculations to study the carbonyls-graphene interaction and found that the weak rc-a interaction can be rationally converted to the strong a-Li-~~ interaction via introducing the groups containing Li atoms. The introduced Li atoms can cooperatively bind with the two aromatic a components through the covalent Li-carbonyl compounds interaction and Li-graphene interaction. The concept of ~（-Li-Tr interaction provides a versatile method to suppress the dissolution of active materials and increase the electronic conductivity at the same time, which gains insight into the design of organic electrode materials for rechargeable batteries with high performance.

摘要：Self-healing polymers represent a class of materials with built-in capability of rehabilitating damages. The topic has attracted increasingly more attention in the past few years. The on-going research activities clearly indicate that self-healing polymeric materials turn out to be a typical multi-disciplinary area concerning polymer chemistry, organic synthesis, polymer physics, theoretical and experimental mechanics, processing, composites manufacturing, interfacial engineering, etc. The present article briefly reviews the achievements of the groups worldwide, and particularly the work carried out in our own laboratory towards strength recovery for structural applications. To ensure sufficient coverage, thermoplastics and thermosetting polymers, extrinsic and intrinsic self-healing, autonomic and non-autonomic healing approaches are included. Innovative routes that correlate materials chemistry to full capacity restoration are discussed for further development from bioinspired toward biomimetic repair.

摘要：Recently, it has been demonstrated that memristors can be utilized as logic operations and memory elements. In this paper, we present a novel circuit design for complementary resistive switch（CRS）-based stateful logic operations. The proposed circuit can automatically write the destructive CRS cells back to the original states. In addition, the circuit can be used in massive passive crossbar arrays which can reduce sneak path current greatly. Moreover, the steps for CRS logic operations using our proposed circuit are reduced compared with previous circuit designs. We validate the effectiveness of our scheme through Hspice simulations on the logic circuits.

摘要：Fractional order proportional-integral-derivative(FOPID) controller generalizes the standard PID controller. Compared to PID controller, FOPID controller has more parameters and the tuning of parameters is more complex. In this paper, an improved artificial bee colony algorithm, which combines cyclic exchange neighborhood with chaos(CNC-ABC), is proposed for the sake of tuning the parameters of FOPID controller. The characteristic of the proposed CNC-ABC exists in two folds: one is that it enlarges the search scope of the solution by utilizing cyclic exchange neighborhood techniques, speeds up the convergence of artificial bee colony algorithm(ABC). The other is that it has potential to get out of local optima by exploiting the ergodicity of chaos. The proposed CNC-ABC algorithm is used to optimize the parameters of the FOPID controller for an automatic voltage regulator(AVR) system. Numerical simulations show that the CNC-ABC FOPID controller has better performance than other FOPID and PID controllers.

摘要：Solidification/stabilization （S/S） is one of the most effective methods of dealing with heavy metal contaminated soils. The effects of cyclic wetting and drying on solidified/stabilized contaminated soils were investigated. A series of test program, unconfined compressive strength （UCS） test, TCLP leaching test and scanning electron microscopy （SEM） test, were performed on lead and zinc contaminated soils solidified/stabilized by fly ash. Test results show that UCS and the leaching characteristics of heavy metal ions of S/S contaminated soils are significantly improved with the increase of fly ash content. UCS of S/S soils firstly increases with the increase of the times of drying and wetting cycles, after reaching the peak, it decreases with it. When the pollutant content is lower （1 000 mg/kg）, the TCLP concentration first slightly decreases under cyclic drying and wetting, then increases, but the change is minor. The TCLP concentration is higher under a high pollutant content of 5 000 mg/kg, and increases with the increase of the times of drying and wetting cycles. The results of scanning electron microscopy （SEM） test are consistent with UCS tests and TCLP leaching tests, which reveals the micro-mechanism of the variations of engineering properties of stabilized contaminated soils after drying and wetting cycles.

摘要：Catalytic oxidation at room temperature is recognized as the most promising method for formaldehyde(HCHO)***‐based catalysts are the optimal catalyst for HCHO decomposition at room ***,flower‐like hierarchical Pt/NiAl‐LDHs catalysts with different[Ni2+]/[Al3+]molar ratios were synthesized via hydrothermal method followed by NaBH4 reduction of Pt precursor at room *** flower‐like hierarchical Pt/NiAl‐LDHs were composed of interlaced nanoplates and metallic Pt nanoparticles(NPs)approximately 3–4 nm in diameter were loaded on the surface of the Pt/NiAl‐LDHs with high *** as‐prepared Pt/NiAl21 nanocomposite was highly efficient in catalyzing oxidation of HCHO into CO2 at room *** high activity of the hierarchical Pt/NiAl21 nanocomposite was maintained after seven recycle tests,suggesting the high stability of the *** on in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)studies,a reaction mechanism was put forward about HCHO decomposition at room *** work provides new insights into designing and fabricating high‐performance catalysts for efficient indoor air purification.