Délégation Centre Limousin Poitou-Charentes

Redox active electrolytes in combination with nanoporous carbon electrodes combine high power with high energy storage performance metrics.

A 4D hydrogel allows user-defined stiffening of the cellular environment and presentation of bioadhesive cues in an orthogonal manner using light of different wavelengths.

Electrospinning is a facile technology for the generation of metal oxide/carbon and metal carbide/carbon nanocomposite fibers.

This paper compares the structure ofAl 2 O 3 ‐SiO 2 xerogels prepared with Al 2 O 3 contents ranging from 21 to 75 wt% (13 to 64 mol%). The 47 wt% Al 2 O 3 xerogel (Al/Si ≅ 1) exhibits anomalously low surface area (≅1 m 2 /g) and skeletal density compared with other Al 2 O 3 ‐Si 2 compositions. Based on the results of nitrogen adsorption/condensation, helium displacement, high‐resolution transmission electron microscopy (HRTEM), small‐angle X‐ray scattering (SAXS), and small‐angle neutron scattering (SANS), we attribute the low surface area and skeletal density (density of the solid phase which is inaccessable to helium) to the formation of closed micropores, whereas the higher surface area materials exhibit a slightly coarser texture comprising open pores with radii of ≅1 nm. X‐ray diffraction (XRD) and 29 SI and 27 Al magic‐angle spinning nuclear magnetic resonance (MASNMR) indicate no anomalous behavior in the 47% sample on molecular length scales. HRTEM indicates the presence of a small fraction of crystallites which is supported by the SAXS results, but it is unknown if this crystallinity is related to low surface area. Low‐field 1 H NMR spin‐lattice relaxation measurements show that the physical structure of all of the ‘wet’ gels is similar implying that pore closure occurs during drying. Consistent with this idea, gel surface area and density increased significantly when the pore fluid (water) was replaced with a lower surface tension fluid (formamide, dioxane, ethanol. water/surfactant).

We introduce a molecular toolkit for studying the dynamics in friction and adhesion from the single molecule level to effects of multivalency. As experimental model system we use supramolecular bonds established by the inclusion of ditopic adamantane connector molecules into two surface-bound cyclodextrin molecules, attached to a tip of an atomic force microscope (AFM) and to a flat silicon surface. The rupture force of a single bond does not depend on the pulling rate, indicating that the fast complexation kinetics of adamantane and cyclodextrin are probed in thermal equilibrium. In contrast, the pull-off force for a group of supramolecular bonds depends on the unloading rate revealing a non-equilibrium situation, an effect discussed as the combined action of multivalency and cantilever inertia effects. Friction forces exhibit a stick-slip characteristic which is explained by the cooperative rupture of groups of host-guest bonds and their rebinding. No dependence of friction on the sliding velocity has been observed in the accessible range of velocities due to fast rebinding and the negligible delay of cantilever response in AFM lateral force measurements.

Ideal cationic polymers for siRNA delivery could result in its enhanced cellular internalization, escape from endosomal degradation, and rapid release in cell cytoplasm, to facilitate knockdown of the target gene. In this study, we have investigated the ability of an in-house synthesized cationic polyrotaxane to bind siRNA into nanometric complexes. This polymer, which had earlier shown improved transfection of model siRNA (luciferase), was used to improve the cellular internalization of the siRNA molecule with therapeutic implications. In cellular assays, the polymer enhanced the knockdown of a gene involved in the pathogenesis of tuberculosis, when the nanocomplexes were compared with free siRNA. The efficacy and cellular non-toxicity of this polymer encourage its further exploitation in animal models of tuberculosis and other intracellular bacterial infections.

The advancement of hypervelocity impact tests in the past year at the Hypervelocity Ballistic Range Laboratory of HAI, CARDC is introduced in this paper,including test capability,the hypervelocity impact test on spacecraft and shield configuration.In the aspect of test capability,the eight sequence laser shadowgraph technology has been developed, which can record the transient impact process.In the aspect of research on hypervelocity impact tests,the temperature effect on ballistic limits of Whipple shields,characteristic of debris cloud generated by impact the aluminum alloy plate,hypervelocity impact test of glass,extravehicular space suit and satellite electronic box have been carried out, and the hypervelocity impact characteristics of these test articles are obtained.

hybrid nanowires (NWs) is effective to reduce both platelet adhesion/activation and bacterial adherence/colonization. The proposed approach allows surface modification of cardiovascular implants which have 3D complex geometries.

The spherical micelles of the carbazole monomer transformed into nanorods in the course of the polymerization. The polymeric nanorods show pH-dependent changes in fluorescence emission and size.

DMC nanoparticles target Bfl1/A1 gene in lung macrophages and effective silencing of Bfl1/A1 gene by DMC nanoparticles paves the way for research on alternative treatment strategies for tuberculosis.

We demonstrate that rapid nanoparticle self-assembly is possible in organic solvents if the temperature is above the melting point of the particles' ligand shell. Flow experiments coupled to small-angle X-ray scattering reveal the agglomeration kinetics and agglomerate structures of alkylthiol-coated gold nanoparticles at different temperatures, interparticle potentials, and times. Our experiments allow to discriminate between the effects of long-range and short-range interactions on self-assembly: crystalline agglomerates formed for a wide range of potentials, but only at temperatures where the short-ranged mobility was sufficient. Rapid superlattice formation in less than 3 s was observed for strongly attractive potentials at high temperatures, implying an assembly rate that is sufficient for large-scale material synthesis. Strong attraction between the particles did not impede high-quality self-assembly when short-ranged mobility was provided by ligands above a specific temperature.

In this study, a simple, rapid and inexpensive approach for the screening of heavy metals with photometric reagents was developed based on porous, anodic aluminium oxide (AAO) films, with detection limits of 0.45 mg L⁻¹ (Co²⁺), 0.25 mg L⁻¹ (Pb²⁺) and 0.59 mg L⁻¹ (Ni²⁺).

In the typical topologies of inductively coupled power transfer(ICPT) system, the drift of the resonant frequency would cause the decrease of the transmission efficiency. Aimed at this problem, a new topology of ICPT system was proposed in this paper. By analyzing the equivalent circuit model which based on first harmonic analysis, the relationships between the voltage and current gains of ICPT system and switching frequency under different quality factors were analyzed,and the topology has a higher power factor was deduced. In order to achieve soft-switching of the ICPT system,the method to design the LCL resonant component parameters was proposed. Based on the reasonable parameters, the influences of quality factor and the coupling coefficient on current or voltage stress of the resonant components were analyzed. A tentative LCL resonant ICPT system was designed with the mentioned resonant component parameters. The feasibility of the design method is verified by the experimental results.

With the analysis of preceding object motion feature and vehicle-borne radar measuring principle,a novel target motion model is established in the vehicle-borne radar coordinate system.This target motion model considers the relative motion of the intertial coordinate,the vehicle coordinate and the radar coordinate system.Also other specialness of ground vehicle were taken into account in the model,such as that the motion of ground vehicle is a 2D motion because of the limitation of ground surface,the vehicle mobility is small and the tracking coordinate system is moving.The whole motion states of the preceding target,including the longitudinal and lateral velocities,the longitudinal and lateral positions were estimated by the algorithm of adaptive Kalman filter,because it was difficult to determine the statistics of the system process noise and measure noise.Finally,road experiments,in which the host car was equipped with millimeter-wave radar and the preceding car was equipped with high precision automotive testing equipments,were carried out to verify the feasibility and performance of the estimation method.The results prove that the method canprovide fine estimation accuracy,better filter convergence and stability.

Growth of the emerging economies like China and India and the production-demand imbalance of oil and gas resources globally have triggered the third peak of oil and gas pipeline construction. Globally, energy resources mainly distribute in six segments, i.e. North America, South America, Europe Central Asia, Middle East, Africa, and Asia-Pacific. Based on oil and gas production and consumption in these segments, this paper describes the current status of oil and gas pipelines in the world, and introduces several large pipelines under planning or construction. This paper also expounds the development and trends of four strategic import channels(i.e. Northwest, Northeast, Southwest, and Offshore) in China, which are designed for ensuring energy security and diversifying energy import channels.

Three dimensional numerical simulation of cold extrusion molding process of propeller shaft involute spline of a motor vehicle is carried out with MSC/Superform software.With numerical simulationthe molding process tracingmechanical field reappearance and molding defect prediction are realizedand cold extrusion molding rules of complicated high accuracy components are exploredand optimization design of blanks and dies is realizedand also criterion is provided for cold extrusion molding production process of spline components. It is shown by process tests that the cold extrusion process and die design are rational and results of numerical simulation and analysis are correct.

Kepemimpinan Militer : Sejarah Singkat, Nilai, Prinsip dan Ciri Khas

The structure topological optimization mathematical model is created with the variable-density method.The processes of structure topological optimization with FEM are introduced.As an example,a bracket of a car was optimized with HYPERMESH software,and bench tests of the optimized bracket were done.Test results indicate that structure topological optimization result is irrelevant with loads;the optimized structure with the FEM-based topological optimization method is rational.

From a service-dominant logic perspective,this paper proposes a conceptual framework that utilizes the construct of relational benefits to explain the link between brand relationship interaction and brand loyalty in popular consumer brands context.The framework posits that brand relationship interaction has indirect impact on brand loyalty through identity-related benefits,confidence benefits and social benefits derived from the long-term relationship between consumers and brands.The results show that the role of the identityrelated benefits on repurchase is the most significant,the role of the confidence benefits on brand commitment is the most obvious and the social benefits has the most obvious influence on brand attachment.Moreover,brand sensitivity plays a moderating role on the mediating process that brand relationship interaction has indirect impact on brand loyalty via relationship benefits.

The purpose,significance,scope and methods of developing the reliability based management for large-scale complicated oil and gas pipeline network systems in China are preliminarily discussed.The methodology to deal with the practical issue of the life cycle phase of pipeline,including the stages of the pipeline pre-planning,design,construction and operation is presented.First,by introducing three variables(pressure,mass flow and temperature),the working and functional status of the pipeline network system within a certain range are described.Hence the calculation method for system reliability function under the expandable limit condition is proposed.A distributed and stepped mathematic model for reliability function is established and both safe transportation of oil and gas pipeline network and stable supply to the markets are taken into consideration.The model allows consistently the quantitative analysis and evaluation of the system reliability.