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The pan evaporation process is essential to understanding the climate change of pan evaporation. To study the physical process of pan evaporation and its interactions with the surrounding environment, an elaborate pan evaporation experiment was carried out by means of micrometeorological method in the arid region of northwest China, in which hourly pan evaporation was measured by E601B, Class A and D20 pans, the local actual evapotranspiration was measured using eddy correlation system. Our results show that the pan water surface and the surrounding land surface constitute a significant non-uniformity of heat and moisture, and the non-uniformity energy exchange between them has an important influence on pan evaporation rate. As the environmental humidity changes, daily actual evapotranspiration and pan evaporation rates have a contradictory tendency, with the relationship between these two evaporations presenting a clear asymmetrical complementary behavior. In addition, a simple pan non-uniformity intensity index ( I E ) is defined as the ratio of pan evaporation to the Penman potential evaporation ( LE ppman ) ( I E = LE pan / LE ppman ). This index reflects the non-uniformity intensity between pan water and the surrounding land. Meanwhile, the comparison of complementary relationship corresponding to three types of pans shows that the degree of complementary relationship asymmetry linearly rises as the intensity of non-uniformity between pan and surrounding environment increases. [ABSTRACT FROM AUTHOR]

Abstract: A simple and effective route for the direct synthesis of Mo2C coatings on graphite matrix is introduced for the joining of copper alloy heat sinks to graphite materials in Tokamak devices. The composition and microstructure of the Mo2C coatings on graphite, and the wetting behaviors of molten copper on coated and uncoated graphite were investigated. Results indicated that the Mo2C coatings were of several tens of micrometers depth in the graphite matrix. The coatings greatly improved the wettability of graphite by copper, and copper could be infiltrated into Mo2C-coated graphite matrix without external pressure. The strong interfacial bonding between copper and the graphite matrix was obtained by utilizing the mechanical interlocking within the space limitations of the graphite network. The Mo2C-modified graphite–copper samples resulted to have the average shear strength of 17±4MPa. [Copyright &y& Elsevier]

Abstract: This paper presents a feasible protocol for the preparation of a novel versatile nanocomposite possessing superparamagnetism via a layer-by-layer method. We combined (3-aminopropyl)triethoxysilane-coated magnetic Fe3O4 nanoparticles (APTES-MNPs) with β-cyclodextrin (β-CD). The following unusual features were integrated in a single nano-system: (a) the silane coating outside the magnetic Fe3O4 cores derived from the hydrolysis of APTES acted as a coupling agent and provided amino group (–NH2) for linking the CD molecule; (b) the outermost CD moieties can function as inclusion sites and specific containers for drugs and biomolecules; (c) the innermost magnetic cores were able to sense and respond to an externally applied magnetic field and their behaviors in vivo or in vitro can be artificially manipulated and navigated. The obtained nanocomposite turned out to be superparamagnetic with a relatively high saturation magnetization value of 69emug−1, which implies potentially promising applications in magnetic drug delivery technology and bioseparation. [Copyright &y& Elsevier]

• The impact of wind farms on the local climate is not simply warming and cooling. • Air temperature becomes colder and the land surface temperature becomes warmer at night. • The significant increase in evapotranspiration may be due to the impact of wind farms. • Wind farm has no or negligible effect on vegetation growth both spatially and temporally. To explore the possible local climatic and environmental impacts of an onshore wind farm in North China, meteorological observation and satellite remote sensing data around the wind farm were collected, and the soil chemical composition within and outside of the wind farm was determined. Our analysis revealed changes in the spatial patterns of wind, air temperature (T a), ground surface temperature (T s), land surface temperature (LST), evapotranspiration (ET), and the normalized difference vegetation index (NDVI) from before to after the construction of the wind farm. The two datasets of meteorological observations showed that wind speed decreased after the construction of the wind farm, with one dataset indicating a significant decrease. Since the construction of the farm, T a and T s have shown increasing trends, and ET has shown a significant increasing trend. The nighttime T a and LST showed opposite trends, with T a decreasing and LST increasing. The change in LST was the greatest at the wind farm and in its downwind zone, indicating that the operation of the wind farm affects the LST within and beyond the 10 km buffer zone. After the wind farm construction, the NDVI showed a significant positive trend. However, increases in the concentrations of Ti and Co were observed, suggesting that the construction and operation of wind farm may promote vegetation growth and cause soil pollution. The monitoring of wind farms needs to be strengthened to reveal the long-term impacts of wind farms on local climates and ecosystems. [Display omitted] [ABSTRACT FROM AUTHOR]

• CoNi alloy encapsulated in N-doped thin graphene shell was synthesized from MOF. • One-pot cellulose conversion to γ-valerolactone using formic acid as hydrogen donor. • γ-Valerolactone yield reached as high as 55.9 % over AgPW/CoNi@NG. • Reaction mechanism of formic acid as hydrogen donor was revealed over CoNi@NG400. One-step efficient conversion of cellulose into value-added γ-valerolactone (GVL) is of great interest because it not only integrates complex tandem reactions in one-step, but also does not need additional hydrogen sources. To achieve this goal, it is crucial to fabricate high-performance catalyst that can accelerate both hydrolysis of cellulose and further transformation of generated stoichiometric levulinic acid (LA) and formic acid (FA) into GVL. CoNi nanoparticles encapsulated in N-doped thin graphene shell gave GVL yield as high as 55.9 % at 200 °C combined with Ag+-exchanged heteropolyacid (AgPW). This composite catalyst is highly resistant to the corrosion of LA and FA, and hence shows high catalytic stability. LA-adsorption FTIR spectra and DFT calculations indicate that LA and FA can penetrate through shell graphene layers into core CoNi sites via cracks. Compared to H 2 , FA can much more rapidly reduce LA because of its low dissociation energy barrier and high dissociation rate. [ABSTRACT FROM AUTHOR]

Shape-memory polymers are a class of materials that show dual or multi-shape competence. Here a solvent casting method was used to prepare composite films from Cu-BTC crystals in poly (l -lactide) (PLLA) to induce crystallization leading to a marked shape memory effect (SME). Extensive physico-chemical characterizations including solid-state NMR indicated that Cu-BTC triggered the crystallization of PLLA for ensuring the entropy needed for the shape memory behavior. The diffusion of polymeric chains inside pores of activated Cu-BTCs ensured interactions which increases the crystallinity as both simulation and experimental results show. Moreover, the segregation of Cu-BTC crystallites to small copper oxide particles due to the activation increases the volume of the crystalline region observed by microscopic images. We compared the identical features of composite prepared in the same method in where small molecule was encapsulated inside Cu-BTC with PLLA/5 wt% Cu-BTC; we were able to show that having the sharp transition of elastic to rubbery state in the vicinity of cold crystallization temperature in PLLA/5 wt% Cu-BTC provides Cu-BTC crystallites to act as netpoints. Moreover, the reinforcement accompanied by increased toughness demonstrates the combination of improved mechanical properties as well as SME of polymers which rarely have attained. Image 1 [ABSTRACT FROM AUTHOR]