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The reduction of α-pinene by NaBH4 was achieved using NiCl2•6H2O in PEG-800/ethanol system under room temperature. Under the optimized conditions, the conversion of α-pinene and the selectivity of cis-pinane reached 97% and 98%, respectively. On the basis of TEM and a series of poisoning experiments, the nature of the active catalytic species for the reaction was discussed.

To achieve the integrity of solid particles coated by water phase (S/W/O) compound droplets, it is important to investigate the transport process of the compound droplets in the horizontal straight channel. The experimental results show that the integrity is significantly influenced by the flow rates and density difference. The water (W) phase is observed to be peeled off from the surface of the particles (polystyrene (PS) shells), mainly caused by the slip velocity of the W phase and the density mismatching among three phases. During the peeling off process, a relative motion between the solid (S) and W phases initially occurs, causing a decrease of the distance (δ) between them, and then, the PS shell is driven to pass through the W/O interface under the action of drag force and net gravity. It is also found that increasing flow rates of both phases contributes to obtaining integrated compound droplets. A boundary that separates the integrated from damaged compound droplets also exits when the fluid properties are fixed. Above the line of the boundary, compound droplets with integrity are prepared. Moreover, the absolute optimum density matching between the S and W phases is less than 0.003 g/cm3, while that between the W and oil (O) phases is less than 0.005 g/cm3.

In the procedures of designing polystyrene-polyvinyl alcohol-CH (carbon and hydrogen elements) (PS-PVA-CH) triple-layer microspheres, there are many methods such as drop-tower technique, emulsion micro-encapsulation, dip (spin) coating, interfacial polycondensation, and spraying technique to prepare the PVA coating. Drop-tower technique, emulsion micro-encapsulation and dip (spin) coating are most-commonly used. The advantages, disadvantages and the research progress of the three methods are summarized in this paper. Emulsion micro-encapsulation is suitable for preparing double-layer microspheres of sizes smaller then 500 m, with high survival ratio and good quality. However,the preparation process is easily influenced by artificial factors. Small-sized double-layer microspheres can also be prepared by the drop-tower technique, and the preparation period is short. But there are still some problems such as the difficulty in designing thedroplet generator, uneven PVA coating and the difficulty in preparing large-sized microspheres. Dip (spin) coating technique can be used to prepare PS-PVA microspheres with sizes larger than 1000 m, but the spread of PVA coating is affected by many factors in this method, and the prepared PVA coating is too thin and not uniform.

Biomass (Chl.a) of benthic algae colonized and developed mature community on different artificial substrata was determined in eutrophic lake Donghu, and species composed and structure characteristic of mature diatom communities on artificial and natural substratum were analysed qualitatively. Biomass variance of benthic algae was compared on four different artificial substratum, granite stone, glass, plastic (PVC) and pine wood during the colonization period, and the peak biomass of benthic algae (Chl.a, 71.0μg/cm2) on PVC was significantly higher than that of the other artificial substrata, which showed PVC was the most suitable artificial substratum for benthic algae. Species composition, dominant species, similarity index and diversity index of benthic diatom communities showed a relatively high degree of consistency between natural and granite artificial samplers, which suggested granite should be the most favourable artificial substratum with benthic algae used as indicatory biology that monitored and evaluated water quality.

All planned inertial confinement fusion (ICF) capsule targets except machined beryllium require plastic mandrels with tight requirements on which the ablator is built. In this paper, the fabrication of poly(-methylstyrene) (PAMS) mandrel is studied. PAMS mandrels are produced by using microencapsulation technique. This technique involves producing a water droplet (W1) encapsulated by a flourobenzen (FB) solution of PAMS (O) with a droplet generator, and this droplet is then flushed off by external phase (W2), forming a water-in-oil-in-water (W1/O/W2) compound-emulsion droplet, which is suspended in a stirred flask filled with external phase to cure. The encapsulation process is based on a microfluid technique, which can achieve the controlled production of millimeter-scale PAMS mandrels. In this work, capillaries-based co-flowing microfluidic triple orifice generator is designed and built to fabricate W1/O/W2 droplets. Two configurations of the droplet generator:one-step device and two-step device, are employed in this experiment. In one-step device, the end of oil phase capillary is located at the same position as the end of inner water phase capillary. So the core droplet and the shell droplet break off from their capillaries ends at the same time, forming a W1/O/W2 droplet. While in the two-step device, the W1 phase capillary tip is located upstream to the W2 phase capillary tip. As a result, the core droplet and the shell droplet depart from the ends of their capillaries respectively, forming a W1/O/W2 droplet as well. Differently, the shell droplet contains only one core droplet in one-step generator, while several core droplets are contained in the shell droplet in two-step generator. In this paper, the mechanism of the droplet formation and the effect of the flow rate on the size of the droplet are studied with these two configurations. Results show that tiny difference between the two generators will lead to great differences in droplet formation mechanism and size control. In the two-step generator, the inner phase flow rate has little influence in the outer diameter of the compound-emulsion droplet. The diameters of the compound-emulsion droplets have a similar change to the diameters of the single droplets (O/W2). In one-step device, the inner phase flow rate has a significant influence on the outer diameter of the double-emulsion droplet because of the existence of W1-O interface. Finally, the compound-emulsion droplets fabricated in this experiment are cured in external phase, after which PAMS mandrels are fabricated. The diameters of the final PAMS mandrels are measured with optical microscope. The distribution of the diameters well concentrates in an area of (200010) upm, which is favorable for producing the PAMS mandrels with a diameter of 2000 upm.

The improvement of enterprise’s competitiveness depends upon the choice of the logistics outsourcing strategy. This paper uses the entropy method to determine the function's weight of the enterprise needed logistics service relatively, uses Value Engineering Theory to analyze the function and cost of logistics services, then takes ratio of sub-function evaluating value and the corresponding cost value as the functional cost value coefficient. Enterprises can select the optimal scheme according to the TOPSIS value sorting. The method provides a basis for the selection and evaluation of enterprises’ logistics outsourcing strategy.