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The environmental impact of dam breach has the features of complexity and uncertainty. There is a lack of systematic and comprehensive research on the environmental impact of dam breach in China. Considering such fuzziness of environment evaluation and the lack of precise data, this work chooses the method of multi-index comprehensive evaluation. Targeting to solve the uncertainty problem of weight calculation and evaluation model, this work introduces the statistic cloud theory to calculate the weight and variable fuzzy set theory to evaluate the environmental impact. We select seven environmental impact factors, including channel morphology, vegetation coverage, water and soil environment, biodiversity, human ecology, and industrial pollution, are selected to construct the evaluation index system and construct the value standard of them. The models are applied to the dam of Shaheji Reservoir in China. The results show that the environmental impact degree of the reservoir member an extremely serious grade mostly, reaching 0.589. Compared with the evaluation results already done, the result of the proposed models shows that the models are reasonable and scientific, which provides a new method for environmental impact assessment of dam breach considering the uncertainty feature of the environment.

We calculated the equilibrium structures and harmonic vibrational frequencies of acrolein (including molecule, cation and anion) using the B3LYP, PBE0, and M06-2X approaches. We also computed the Franck–Condon factors and simulated the photoelectron spectra of acrolein molecules and anions. The adiabatic ionization energy (AIE) and electron affinity were computed using the CCSD(T) approach via extrapolation to the complete basis set limit. Trans-acrolein is identified as the primary isomer responsible for the photoelectron spectra of acrolein being observed. The calculated AIEs were consistent with the experiment. The cis-acrolein anion is predicted to be more stable than its trans- counterpart. However, the potential barrier might prohibit the isomerization of the acrolein anion. Accordingly, the type of isomer of acrolein anion that will be produced from electron-attaching to the more stable trans-acrolein molecule remains unknown. The simulated photoelectron spectra of the acrolein anion can be used to identify the isomer being produced.

Stimuli-responsive nanocarriers for anticancer drug and gene co-delivery are promising strategy in cancer therapy. The ultimate goal is to deliver high local concentration of therapeutic agents with no premature release and result in synergistic effects for combination therapies. In this work, we developed a redox stimuli-responsive and synergistic co-delivery system for anticancer drug DOX and p53 gene for potential cancer therapy. A dendronized chitosan derivative (CP) as a "gatekeeper" to control release the drug was used to modify MSNs via a disulfide linker and improve the gene transfection efficiency. Stimulus-induced release of the DOX was studied in the presence of glutathione (GSH), which showed that polymer shell was shed and accelerated the release of embedded drugs inside the tumor cells under a GSH-rich environment. The obtained nanoparticles showed good gene delivery ability in vitro by inducing an obvious increase in p53 protein expression in Hela cells. Apoptosis analysis confirmed that DOX and p53 could be co-delivered to the Hela cells by MSN-SS-CP nanocarriers and induced significant cell apoptosis. These results demonstrated that the dual delivery system resulted in synergistic effects and lead to an effective cancer cell apoptosis, which may be promising for cancer therapeutic application.

The composites reinforced with Ti 5 Si 3 -coated SiC P showed higher relative densities and mechanical properties than those of uncoated ones. It is mainly due to the translation of Ti 5 Si 3 coating layer into Al 3 Ti interfacial layer during the sintering process, increasing the interfacial bonding strength between α-Al and SiC P .

Resveratrol-loaded solid lipid nanoparticles (SLNs) modified by polyethylene glycol (PEG2000) (RES–PEG–SLNs) were prepared to study the stabilizing influences of PEG2000 on SLNs properties including loading capacity, particle size, photostability, and release. The micromorphology, particle size distribution, drug–lipid–modifier interaction and crystalline structure were characterized to elucidate stabilizing effects of PEG2000 on SLNs. Compared with ordinary SLNs, SLNs modified by PEG2000 at relatively low amounts of [m(PEG2000):m(lipids) = 1:10] exhibit high drug loading, steady nanoparticle size distributions, photostability and sustained release. According to characterizations, RES–PEG–SLNs formation is dependent on the physical interactions of drug–lipid–modifier. Since PEG2000 is doped into lipid matrix in a non-crystalline state, the lipids crystalline arrangement is disrupted. Additionally, RES–PEG–SLNs are crystallized in a PEG2000/lipid eutectic mixture rather than a simple mixture, inhibiting the lipid polymorphism transformation from α- to β-form, and therefore preventing drug exclusion from the lipid matrix. The PEG2000/lipid matrix contains lattice defects, which allow for the incorporation of more resveratrol and preventing it from photodegradation effectively. In contrast to the burst release of SLNs modified without PEG2000, resveratrol is released more slowly from the lattice defects in lipid matrix of RES–PEG–SLNs, resulting in a sustained release fitted by a two-stage exponential kinetic equation. PEG2000 is distributed on the RES–PEG–SLNs surface, increasing repulsion between nanoparticles and avoiding particles aggregation. These results confirm that both matrix doping effects and surface steric hindrance produced by the presence of PEG2000 play important roles in maintaining high loadings, nanoparticle size, photostability and sustained release.

A rapid and sensitive method for determination of trace carbaryl in water by using diallyl phthalate-europium (Eu 3+ ) as fluorescent probe was developed in this paper. The interaction between Eu 3+ , diallyl phthalate and carbaryl was studied by high-resolution mass spectrometry, and the change of fluorescence spectra of complexes before/after binding with carbaryl was also investigated. The influencing factors of fluorescence intensity including solution pH value and interferents were evaluated. The results showed that diallyl phthalate was complexed with Eu 3+ in a molar ratio of 2:1 to form stable complexes. Carbaryl could also interact with this probe to form multiple complexes, which significantly increased the fluorescent efficiency of Eu 3+ -diallyl phthalate probe. The fluorescence intensity showed good linear relationship with the concentration of carbaryl at pH 9.0 using 245 nm/615 nm as excitation/emission wavelength in the range of 6.25 × 10 −8 − 2.5.0 × 10 −6 M with linear correlation coefficient of 0.9968. The detection limit of the method was 9.6 × 10 −9 M. Water samples were extracted by acetonitrile, and then detected by using Eu 3+ -diallyl phthalate as fluorescent probes. The recoveries of the method were between 91.8%−94.5%, with RSDs less than 6.1%. The method was suitable for rapid determination of carbaryl in water samples.

Colloque avec actes et comité de lecture. Internationale.; International audience; On s'intéresse au guidage d'ondes ultrasonores dans des structures phononiques ""composites"" périodiques ou quasi-périodiques élaborées à partir de deux types de réseaux de tiges cylindriques, acier (Ø 1mm) et polyéthylène (Ø 1,5 mm) immergées dans l'eau. Les bandes passantes fréquentielles des structures en acier ou en polyéthylène exclusivement sont au préalable déterminées, les espacements étant fixés. Le choix adéquat des fréquences du signal harmonique incident (de l'ordre de 170 kHz) sur les structures phononiques permet alors de réaliser le guidage étroit via un couloir de tiges en acier pratiqué dans un environnement de tiges en polyéthylène. Plusieurs géométries de couloir sont considérées en vue du guidage, linéaire puis courbe. Dans ce dernier cas, on montre l'importance du rayon de courbure sur la propagation. Des simulations temporelles sont réalisées en utilisant la méthode des éléments finis. Des mesures expérimentales sont effectuées et comparées aux prédictions théoriques

An algorithm for arbitrary polygonal aggregate generation is proposed based on secondary development of ANSYS in this paper. It is established on the basis of circular aggregate model, and the central angle is the control parameter to generate poristic polygon as the coarse aggregate of concrete. The concrete numerical samples with first gradation of aggregate and two gradation of aggregate are generated. The aggregate fraction of polygon sample is lower about 20% than the original circular aggregate sample in the statistical sense. The results show that the proposed method can simulate gravel aggregate appropriately as long as the central angle and the aggregate percentage of original circular aggregate sample is reasonable controlled.

To establish an appropriate random aggregate model at meso-level is the basis for successfully simulating the meso-mechanical behaviors of concrete. This paper proposes a new simple method to generate random aggregates of concrete by PFC2d. And the distribution of aggregate in the two-dimensional concrete specimen cross-section is determined by Walraven formula. The results show that the numerical aggregate distribution matches well with the theoretical grading curve.

The deformations and stresses of a concrete face rockfill dam (CFRD) for dam construction and reservoir impoundment were simulated by the element add/remove technique of ABAQUS. And, the sensitivity analysis of main parameters of the Duncan-Chang E-B model was carried out by the method of univariate sensitivity analysis and the critical sensitivity parameters of the deformation and stress on the CFRD were obtained. This research has some guidance and reference for future similar projects design and monitoring.

In order to simulate the seepage field with drain pipes, the air element method is used in this paper. In this method, the pipe elements are regarded as a kind of material with high permeability coefficient and an equivalent hydraulic conductivity is assigned to them. Thus these pipe elements can be included in the conventional seepage calculation as other common elements. Moreover, the difficulty of giving water head boundary to the inner surface of pipes directly is avoided. According to the seepage calculation of the channel with large number of drain pipes in Huangyou part of the middle line in South-to-North water transfer project, the results show that, with drainage-piping, the pore water pressure in channel foundation is reduced significantly.

4-Methylamino-N-allylnaphthalimide (4-MAANI), a functional monomer with fluorescent effect, was synthesized for the imprinting and specific uptake of creatinine, an important clinical marker for kidney function. 4-Methylamino-N-allylnaphthalimide was synthesized from the reaction of 4-bromo-1,8-naphthalic anhydride with allylamine to form 4-bromo-N-allylnaphthalimide and further to react with methylamine. Excitation and emission of the fluorescent monomer was investigated by both a three-dimensional plot of fluorescent intensity versus excited and emitted wavelengths and a corresponding contour plot. The photoluminescence properties of the as-prepared conjugated species were also studied. 4-Methylamino-N-allylnaphthalimide (4-MAANI) fluorescent monomer, methacrylic acid (MAA) functional monomer, ethylene glycol dimethylacrylate (EGDMA) cross-linker, and 2,2'-azobisisobutyronitrile (AIBN) initiator were then utilized in the presence of creatinine template for the processing of heat-induced polymerization. FT-IR analysis was used to confirm the successful synthesis of 4-MAANI. The specific recognition cavity for creatinine was then created from the polymer matrix after the removal of creatinine by proper solvent. The imprinting effect as well as selectivity from the creatinine containing mixture was also evaluated. The grouped clusters from the emitted fluorescent intensities of the imprinted and nonimprinted polymers before and after rebinding of creatinine were obtained and discussed. Serum spiked with a different concentration of creatinine was also used to confirm the feasibility of clinical applications in the future. Successful recognition of the creatinine molecule via the combined effect of molecular imprinting and photoluminescence of the imprinted polymeric material was thus confirmed in this work.

The liposome particle entrapping atractylone extracted from Atractylodes macrocephala Koidz.was prepared and characterized. The liposome suspension of atractylone was formed by supercritical carbon dioxide (SC-CO2) expansion process and was dried by vacuum freezing. The physicochemical properties of the liposome particle including microstructure, size, entrapment efficiency and drug loading content were measured. The liposome formation could be controlled by adjusting the processing conditions such as pressure, temperature of SC-CO2 and mole fraction of ethanol in SC-CO2 [ x (CH3CH2OH)]. The entrapment efficiency, loading content, and average size of liposome particle were 83.1％, 5.1％ and 506.5nm respectively under the optimum conditions of 30MPa，338K and x (CH3CH2OH) = 15％.The liposome particle presented good performance of redispersion to liposomal suspension. The physicochemical properties of liposome particle including entrapment efficiency, dissolution rate and stability complied with the provisions of Chinese pharmacopoeia. The results show the liposome particle can be used as an solid immediate for hepatic target of drugs.

Phononic structures or crystals made of rows of steel pipes privilege the existence of band gaps and pass bands. The first ones are frequency domains where the incident wave cannot pass through the structure. By introducing small changes about the positioning of the pipes, it is possible to expand greatly the width of the band gaps. By varying the thickness of the pipes in a phononic crystal with a square symmetry, the effect of an incident plane wave which propagates in the direction of the variation is to create thin pass bands in the band gap obtained initially when the pipes have the same thickness. If the incidente wave propagates perpendicularly to the direction of the thickness variation of the pipes, convergent or divergent acoustic lenses which could deviate acoustic beams are created. Finally, when a crystal constituted by the steel pipes is inserted in an array of polyethylene pipes, numerical simulations show that a sound wave can be guided at frequencies corresponding to the pass bands of a steel phononic crystal., Des structures phononiques ou cristaux phononiques constitués de réseaux ordonnés de tubes en acier favorisent l'existence de bandes interdites et de bandes passantes. Les premières sont des domaines fréquentiels où une onde incidente ne peut traverser de telles structures. En introduisant de légères variations sur le positionnement des tubes, il est possible d'élargir considérablement les bandes interdites. En faisant varier l'épaisseur des tubes dans un cristal phononique à symétrie carrée, l'effet d'une onde plane incidente parallèlement à la direction de variation est de créer de fines bandes passantes dans la bande interdite obtenue initialement lorsque les tubes ont même épaisseur. Si l'on envoie l'onde incidence perpendiculairement à la direction de variation de l'épaisseur des tubes, on crée des lentilles acoustiques convergentes ou divergentes déviant les faisceaux acoustiques. Enfin, lorsque dans un cristal composé de tubes en polyéthylène on insère une allée de tubes en acier en forme de virages, les simulations numériques montrent qu'une onde acoustique peut être guidée aux fréquences correspondant aux bandes passantes du cristal phononique entièrement en acier.

The aim of the present work is to evaluate influences of doping trehalose into solid lipid nanoparticles (SLNs) on drug loading. SLNs were prepared by the emulsion-evaporation and low temperature-solidification method, using glyceryl monostearate as a lipid, phosphatidylcholine as a surfactant, trehalose as a modifier and resveratrol as a model drug. As the SLNs were doped by trehalose at a low amount [m(trehalose):m(lipids) = 1:5], entrapment efficiency and loading capacity were enhanced to (81.37 ± 1.50) and (8.71 ± 0.13)%, respectively. Based on morphology, phase transformation and crystalline structure of SLNs, trehalose was doped into lipid matrix in a non-crystalline state, disrupting the lipid crystallinity and inducing lattice defects.The lipid matrix was crystallized in polymorphic forms composed of α-form and β′-form and β-form, resulting in prevention of drug expulsion from the lipid matrix. The trehalose was interacted with the lipid, facilitating the formation of trehalose/lipid eutectic dopant. The dopant contained lattice defects, allowing for the incorporation of more resveratrol in a amorphous state, contributing to increase of entrapment efficiency and loading capacity. These results confirm stabilizing effects of doping trehalose on improvement of drug loading are attributed to the lipid crystal type and structure of lipid matrix containing lattice defects. Practical applications: Trehalose-doping is an innovative approach to the improvement of loading properties of SLNs. Compared with ordinary SLNs, SLNs doped with trehalose at low amounts exhibit higher drug loading, presenting the potential utility of these nanoparticles as a drug delivery system for hydrophobic drugs. Trehalose modification on improvement of drug loading of SLNs are attributed to the lipid crystal type and structure of lipid matrix containing lattice defects induced by doping trehalose.