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A three-dimensional (3D) solid-fluid coupling model is proposed with the well-known science and engineering analysis software ABAQUS for reservoirs of multi-thin layered pay zoon with low permeability. The cohesive element based on damage mechanics is used for describing fluid flow through fractures and rock crack propagations. Self-developed subroutines are incorporated into ABAQUS for considering viscosity and leak off coefficient of proppant-laden fluid as well as pressure applied on the proppants in the fracture(s) already constructed in preceding fracture step(s). The layer-by-layer fracturing process of a vertical well in Daqing Oilfield of China and interference between different layers are simulated with the model. The numerical results are well coincident with the corresponding data measured in the field. The effects of layer’s spacing on fracture results are studied.

The technology of fishbone multilateral wells has been extensively applied worldwide in oilfield development. However there are few published models about fishbone multilateral wells' productivity. Based on conformal transformation and mirror image theory, a semianalytical model was derived for horizontal wells and fishbone multilateral wells' productivity in row well pattern, and verified through the electrolytical model experiment. The matching result showed there was only 12.15% maximum error.

A three-dimensional ternary Sn–Zn–Ni film was prepared by a modified chemical bath deposition method, which involved the alkaline disproportionating reaction and other redox reactions happening simultaneously. Sn was obtained by the disproportionating reaction of Sn(OH)2−4, while Zn and Ni were produced by the aid of two different kinds of reducing agents: NaBH4 and NaHPO2.H2O together. X-ray diffraction, SEM and energy dispersive X-ray spectrometry (EDS) were used to characterise the phases, morphology and composition of the films respectively. The EDS results showed that the elements of Sn, Zn and Ni could all be found in both films by optimising the deposition conditions. Ternary Sn–Zn–Ni film was deposited on copper foam for use as anode in a lithium ion battery. The electrode showed a high level capacity of ∼500 mAh g−1 with good cycle stability for 35 cycles.

This study provides the first detailed table of normal development of the rosy barb embryo, from fertilization to post-hatching. We define six broad periods of embryogenesis, i.e. the zygote, cleavage, blastula, gastrula, segmentation and larval periods. These divisions highlight the changing spectrum of major developmental processes occurring during these periods. Stages that subdivide the periods are named, not numbered as in most other series. The stages and their names are based on morphological features usually readily identified by examination of the live embryo under a stereomicroscope. These provide a detailed embryological staging by morphological criteria for future studies on molecular biology and biotechnology in this species.

The evaporation state of solution aerosol thermolysis (SAT) was modeled to study the effect of various parameters on solid particle formation by solute precipitation. A comparison of the characteristic time constants for various processes demonstrated that droplet shrinkage and solute diffusion are the slowest processes, and that the fast processes, i.e., vapor diffusion and heat conduction in the gas phase and the liquid phase, can be assumed to have reached steady state. Differential equations for these faster processes were thus simplified and were solved numerically along with a modified solute diffusion equation, using an explicit first-order finite difference scheme. The computations were done until the solute concentration at the droplet surface reached the critical supersaturation. Then, if the solute concentration at the droplet center is higher than the equilibrium saturation, volume precipitation is proposed to occur. Solutes with a large difference between critical supersaturation and equilibr...