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The aggregation-induced emission (AIE) luminogens are now showing strong potential in mimicking the energy donor of fluorescence resonance energy transfer (FRET) system. Herein, one highly efficient FRET system 1-NiR is successfully fabricated in aqueous solution based on an AIE active compound 1 and fluorescence dyes (Nile red (NiR)). 1 acts as the energy donor and NiR acts as the acceptor in the FRET system with the optimum concentrations ratio [1]/[NiR] = 100. Besides, the AIE(1) itself displays excellent selectivity for Cu2+ ions at 525 nm with the detection limit of 1.32 × 10−7 M. While through the FRET system of 1-NiR system, the detection limit of Cu2+ can be further decreased to 9.12 nM by monitoring the fluorescence at 630 nm. As a result, using an AIE probe to detect Cu2+ based on FRET mechanism is a promising strategy.

To evaluate the spatial distribution of chemicals and their contribution to processing quality, wheat grains were layered into nine fractions from the surface to the center layer. The content of total starch, amylose and amylopectin gradually increased from the surface layer to inner layer, while albumin, globulin and total protein decreased in this direction. Contents of gliadin, glutenin, high molecular weight glutenin subuints (HMW-GS) and glutenin macropolymers (GMP) increased from the surface layer, and peaked at the second or the third pearling layer, and then decreased till the center layer. The mean particle diameter of starch granules increased gradually from the surface to inner except at P9. Bread baking performance was the best for flour at the mid layers, while was the worst for flour from the surface layer, especially in terms of taste and texture. Biscuit making performance was the best at the center layers, while poorest at the surface layer.

TEM-1 beta-lactamases can accurately catalyze the hydrolysis of the beta-lactam rings in beta-lactam antibiotics, which make beta-lactam antibiotics lose its activity, and the prerequisite for the hydrolysis procedure in the binding interaction of TEM-1 beta-lactamases with beta-lactam antibiotics is the beta-lactam rings in beta-lactam antibiotics. Therefore, the binding of TEM-1 beta-lactamase to three beta-lactam antibiotics including penicillin G, cefalexin as well as cefoxitin was explored here by frontal affinity chromatography in combination with fluorescence spectra, adsorption and thermodynamic data in the temperature range of 278-288K under simulated physiological conditions. The results showed that all the binding of TEM-1 beta-lactamase to the three antibiotics were spontaneously exothermic processes with the binding constants of 8.718×103, 6.624×103 and 2.244×103 (mol/L), respectively at 288K. All the TEM-1 beta-lactamases were immobilized on the surface of the stationary phase in the mode of monolayer and there existed only one type of binding sites on them. Each TEM-1 beta-lactamase bound with only one beta-lactam antibiotic and hydrogen bond interaction and Van der Waals force were the main forces between them. This work provided an insight into the binding interactions between TEM-1 beta-lactamases and beta-lactam antibiotics, which may be beneficial for the designing and developing of new substrates resistant to TEM-1 beta-lactamases.

Epidermal biophysical properties can be affected by many factors, including body site, age, gender, ethnicity, disease, temperature, humidity, and ultraviolet (UV) radiation. Information about variation of epidermal biophysical properties with seasons is still limited. In the present study, we determined seasonal variation of epidermal biophysical properties of women in Kunming, China.A total of 72 women, aged 22.96 ± 2.11 years, were enrolled in this study. Transepidermal water loss rates (TEWL), stratum corneum (SC) hydration, sebum content, melanin index (MI), erythema index (EI), and L*a* values were measured on the right cheek and the right forearm, using a non-invasive skin physiological instrument in the spring, summer, autumn, and winter in Kunming, China.On the cheek, TEWL, SC hydration, sebum, MI, and L*a* values varied greatly with seasons (P .05). SC hydration, sebum, MI, and a*value peaked in the summer, but went lowest in winter. In contrast, TEWL and L*value went lowest in summer but peaked in winter. Similarly, SC hydration, MI, and L*value also varied with seasons on the forearm (P .05). In addition, SC hydration, sebum, MI, EI, and a*value of the cheek were higher than that of the forearm (P .001), but L*values of the cheek were lower than that of the forearm (P .001). There were no correlations among TEWL and MI, EI, and L*a*values in any season (P .05).Both epidermal permeability barrier function, sebum, and skin pigment in healthy women vary seasons in Kunming, China.

The Dongying anticline is an E-W striking complex fault-bounded block unit which located in the central Dongying Depression, Bohai Bay Basin. The anticline covers an area of approximately 12 km2. The overlying succession, which is mainly composed of Tertiary strata, is cut by normal faults with opposing dips. In terms of the general structure, the study area is located in a compound transfer zone with major bounding faults to the west (Ying 1 fault) and east (Ying -8 and -31 faults). Using three-dimensional seismic data, wireline log and checkshot data, the geometries and kinematics of faults in the transfer zone were studied, and fault displacements were calculated. The results show that when activity on the Ying 1 fault diminished, displacement was transferred to the Ying -8, Ying -31 and secondary faults so that total displacement increased. Dynamic analysis shows that the stress fields in the transfer zone were complex: the northern portion was a left-lateral extensional shear zone, and the southern portion was a right-lateral extensional shear zone. A model of potential hydrocarbon traps in the Dongying transfer zone was constructed based on the above data combined with the observed reservoir rock distribution and the sealing characteristics of the faults. The hydrocarbons were mainly expulsed from Minfeng Sag during deposition periods of Neogene Guantao and Minghuazhen Formations, and migrated along major faults from source kitchens to reservoirs. The secondary faults acted as barriers, resulting in the formation of fault-bound compartments. The high points of the anticline and well-sealed traps near secondary faults are potential targets. This paper provides a reservoir formation model of the low-order transfer zone and can be applied to the hydrocarbon exploration in transfer zones, especially the complex fault block oilfields in eastern China.

Dual sites fluorescence compound 1 based on 5-bromosalicylaldehyde and 2-benzothiazoleacetonitrile was synthesized. 1 exhibited different aggregation-induced emission (AIE) state in different solution boosting different emission. Different aggregated states gave different chance for H2S and Hg2+ to respond with the formation of new aggregated states. Especially, 1 responded to H2S selectively with an ultrafast rate within 20 s. Intramolecular and intermolecular hydrogen bonding play an important role on the aggregated state conversion. Herein, the notion of “AIE Transformers” was put forward for the first time. It permits us to study their aggregation state with their photophysical and functional changes.

A two-dimensional contraction channel with a theoretically designed concave-oblique-convex wall profile is proposed to obtain a smooth planar-to-planar shock transition with shock intensity amplification that can easily overcome the limitations of a conventional shock tube. The concave segment of the wall profile, which is carefully determined based on shock dynamics theory, transforms the shock shape from an initial plane into a cylindrical arc. Then the level of shock enhancement is mainly contributed by the cylindrical shock convergence within the following oblique segment, after which the cylindrical shock is again "bent" back into a planar shape through the third section of the shock dynamically designed convex segment. A typical example is presented with a combination of experimental and numerical methods, where the shape of transmitted shock is almost planar and the post-shock flow has no obvious reflected waves. A quantitative investigation shows that the difference between the designed and experimental transmitted shock intensities is merely 1.4%. Thanks to its advantage that the wall profile design is insensitive to initial shock strength variations and high-temperature gas effects, this method exhibits attractive potential as an efficient approach to a certain, controllable, extreme condition of a strong shock wave with relatively uniform flow behind.