In this work, a polyethylene terephthalate (PET) nonwoven support was prepared by wet-laid and hot-press technology and used as support for separation membranes. The properties of the PET nonwoven support were studied to determine the effect of hot-pressing parameters and PET fiber ratio, and were optimized by response surface methodology. Result showed that the PET nonwoven support with 62% low melting point PET (LPET-180) fibers obtained satisfactory properties and structure after hot pressing at 220 °C under the pressure of 9 MPa for 20 s. The response surface analysis indicated that the temperature and time of hot pressing and the fiber ratio were the most important factors affecting the strength and air permeability of the PET nonwoven support. After hot pressing, the PET nonwoven support exhibited interconnected structure, small pore size, low porosity, and high strength. Then phase inversion technique was applied to prepare a polysulfone (PSF) layer on the PET nonwoven support and an ultra-thin polyamide (PA) active layer was prepared by interfacial polymerization on the PSF layer. The practicality of PET nonwoven support was verified by testing the pure water flux and retention of the PA composite membrane and the structural change of the PA composite membrane before and after use. The results proved the feasibility and remarkable application prospects of hot-pressed wet-laid PET nonwoven support as support for separation membranes.

Growth, nitrogenous excretion and energy budget of juvenile yellow catfish, Pelteobagrus fulvidraco (initial body weight 1.17 ± 0.28 g) at various levels (50%, 60%, 70%, 80%, 90% and 100% satiation per day) were investigated with feeding diet containing 40% protein. Specific growth rate of yellow catfish increased (2.79–3.34% day) significantly (P<0.05) with ration level (RL) increasing. Feed conversion efficiency, feed protein retention efficiency and feed energy retention efficiency increased with the increase in RL, peaked at 70% of satiation, and then decreased at higher ration, with the ranges of 78.97–97.28%, 31.31–37.93% and 26.55–31.88% respectively. Both nitrogenous excretion (u, mg g⁻¹ day⁻¹) and faecal production (f, mg g⁻¹ day⁻¹) increased significantly with the increased RL, and ranged between 0.94–1.38 and 0.69–1.24 mg g⁻¹ day⁻¹ respectively. Apparent digestibility coefficients in dry matter, protein, energy decreased significantly as ration increased, with ranges of 54.42–69.64%, 78.24–89.90% and 69.66–82.07% respectively. Energy budgets of juvenile yellow catfish at satiation RL was: 100C=30F+8U+33R+29G or 100A=54R+46G.

Antibacterial viscose cellulose sponges (VCSs) were fabricated by heating cellulose xanthogenate (viscose) containing HAuCl₄·nH₂O. Viscose was used as the reducing agent and stabilizer for the in situ synthesis of Au nanoparticles (AuNPs) onto the VCSs. The morphology, structures, thermal properties, mechanical performance, and antibacterial activities of the sponges were investigated. Results indicate that AuNPs were uniformly immobilized in the VCSs, and the resulting complexes (AuNPs@VCSs) showed enhanced thermal stability and mechanical properties. Additionally, the AuNPs@VCSs exhibited remarkable antibacterial activities, with zone of inhibition diameter of 35.7 and 37.1 mm for Staphylococcus aureus and Escherichia coli, respectively. The process is simple and applicable at the industrial level and can be applied to the fields of cleaning and sanitation.

During the process of jujube planting, there are not only natural risks caused by natural disasters but also market risks caused by price factors. In the study, firstly, wavelet analysis method was used to stabilize the jujube yield per unit area and the jujube price from 1997 to 2018 in Aksu region, Xinjiang, China. Secondly, EasyFit software was used to fit the distribution functions of yield per unit area and price, respectively. Thirdly, the optimal Copula function which connects the marginal distribution functions and its joint distribution function was selected with the principle of “the minimum square distance from the empirical Copula function.” Finally, taking the premium rate and the insurance amount as two decision variables, the farmer’s risk minimization as the objective function, around the four constraints of functions and role of insurance, the nonspeculative nature of insurance, the sustainability of insurance, and the moral hazard factors and the farmers’ willing to participate in insurance, the Copula-stochastic optimization model was set up to determine the premium rate of jujube revenue insurance in Aksu region.

The development of foreign trade has become one of the focuses of the world's attention. The prospects and competitive forces reveal the developing possibility of one country or region. The southwest minority region is no exception. On base of the existing literatures, the empirical study shows that during the 30-year reform and opening-up: (1) foreign trade has contributed a lot to the GDP growth of foreign trade and still has great potential to be tapped. (2) There is a positive correlation between the foreign trade and GDP. And the correlation coefficient (0.991) between GDP and import is bigger than the correlation coefficient (0.988) between GDP and export. It indicates that import has more positive effect on GDP growth. Finally, the paper points out that in order to maintain the economic growth, Southwest minority region must unswervingly implement the opening-up policy and be aware of trade protectionism.