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The lithium ion-sieve precursor was prepared with LiOH and Mn (CH3COO)2 as the starting reagents, H2O2 as the oxidant and ethanol solution (volume percent 2.5%) as solution by combination of sol-gel, hydrothermal and low-temperature solid state methods, and then changed into lithium ion-sieve after eluting Li+ by the mixture of HCl and Na2S2O8 solution. The influence of synthetic conditions on the structures and adsorption properties of lithium ion-sieve was investigated in detail. The results suggest that the pure phase lithium ion-sieve can be synthesized when Li/Mn molar ratio is 3/1, 3.2mL H2O2 is added after LiOH and Mn (CH3COO)2 react for 36h and the heat treatment way of programmed temperature from 410°C (2h) to 510°C (3h) is adopted in the progress of solid state reaction. The loss rate of dissolved Mn is less than 2.5% during pickling Li+. And the highest adsorption capacity can achieve 20.5mg/g.

Much attention has been paid to membrane-type lithium adsorbents to overcome the shortages of the leakage of powder, poor permeability and difficult recycle for powder lithium adsorbents. In this work, a series of membrane-type adsorbents of spinel-type manganese oxides were converted from lithium manganese oxide precursor membranes by acid treatment. Precursor membranes were prepared by solvent exchange method using polyvinylidene fluoride (PVDF) and Polyether sulphone (PES) respectively as binders, powder LiMn2O4 as the precursor and N,N-dimethyl acetamide (DMAc) as the solvent. The preparation conditions were investigated by changing the binder and the concentration of powder LiMn2O4. The surfaces and morphology of membrane-type adsorbents were observated by scanning electron microscope. The comparation of the capacities of lithium desorption from precursor and adsorption for membrane-type adsorbents based on different binders shows that PVDF is more suitable to be the binder than PES with liquid film thickness of 0.25mm, and the proper concentration of PVDF and powered LiMn2O4 are respectively 12% and 60%.

Multiwalled carbon nanotubes (MWNTs) grafted by Poly(methyl methacrylate) (PMMA) can well disperse in organic solutions like toluene，which were synthesized via a microemulsion polymerization of methyl methacrylate (MMA) in the presence of acid-modified multiwalled carbon nanotubes (c-MWNTs). The polyamide thin-film nanocomposite (TFN) membranes with embedded PMMA-MWNTs were prepared using piperazine (PIP) and trimesoyl chloride (TMC) on a polyacrylonitrile (PAN) porous substrate via interfacial polymerization for selective permeability. PMMA-MWNTs’ structure was analyzed by Fourier transform infrared spectrophotometry (FTIR), Raman spectrophotmetry (RAM), Scanning electron microscope (SEM) and thermo gravimetric analysis (TGA). Orthogonal experiment was used to study the effect of PIP concentration, TMC concentration and concentration of PMMA-MWNTs in organic phase. The results showed that the membrane performances is good, Na2SO4 rejection is above 98% and water flux is up to 150% improvement over the TFC membrane as PIP in aqueous phase was 2g/L, TMC and PMMA-MWNTs in organic phase were 4g/L and 0.67g/L, respectively . Demonstrated PMMA-MWNTs in the nanofiltration membrane can improve selective permeability.

Macromolecules chain transfer agents (MCTA) were synthesized through the reversible addition fragmentation chain transfer polymerization (RAFT) by using S-l-Dodecyl-S′-(α, α′-dimethyl-α-acetic acid) trithiocarbonate(MTTCD), S, S′-bis (2-hydroxyethyl-2′-dimethylacrylate) trihiocarbonate (BDATC), 2-cyanoprop-2-yl dithiobenzoate (CPDB) as the chain transfer agents, methacrylamide (MAM) as the first polymerization monomer. The results showed that the structures of the end-group of dithiocarbamates had significant effects on the activity of dithiocarbamates for the polymerization of PMAM. The derived block copolymer (PMAM-b-PNVP) was prepared by using the above mentioned polymer as macromolecular RAFT agent and NVP as the second polymerization monomer. N-vinyl-γ-sodium aminobutyrate-sodium methacrylate copolymer (VSA-MSA) containing -NH2 and -COOH as the CO2 facilitated carrier, a kind of new fixed carrier membrane material for CO2 separation, was synthesized by hydrolysis of the resulted PMAM-b-PNVP. The chemical composition and structure of PMAM-CTA, PMAM-b-PNVP, MSA-VSA were analyzed by FTIR, 1HNMR and DSC, the molecular weight and polydispersity index were analyzed by GPC. The Relative molecular mass of polymer was controllable. The polydispersity index (1.2~1.3) of the obtained polymer was narrow via using MTTCD and BDATC. The VSA-MSA/PS composite membranes were prepared. The CO2 and N2 permeation performance were tested at different pressure. The results showed that the resulted composited membrane had a CO2 permeation rate of 1.2×10-4 cm3 (STP) cm-2s-1cmHg-1 and a N2 permeation rate of 8.57×10-7 cm3 (STP) cm-2s-1cmHg-1 and an ideal CO2/ N2 selectivity of 140.02 at a feed gas pressure of 7.6 cmHg and 30 ℃.

The technologies of computer numerical simulations on casting process has penetrated into the every field of shape process, and offer a efficient tool for casting technological design. The paper briefly introduces the characteristics of the Flow-3d software on the principle and function, which is superior to that of other casting simulation software. Then, many die casting casts have been modeled and simulated, focus on the content of Pre-processing, summed up the major principles and skills on STL Import, Mesh Building and Control parameters selection of Flow-3D software by using the means of analogy.

The high pressure die casting (HPDC) process of an ADC12 aluminum alloy auto part is researched by the software ProCAST and FLOW-3D, respectively. The possible HPDC defects of the auto part are analyzed. The difference of the filling process with the same technological parameter is studied. Compared with the simulation result of ProCAST, FLOW-3D software simulation result is closer to the die casting of the actual production.

Polyacrylonitrile/montmorillonite (PAN/MMT) nanocomposite with amidoxime functionality was prepared from acrylonitrile monomer(AN) and montmorillonite(MMT) through in-situ intercalation polymerization. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction patter (XRD) were employed to characterize the obtained Na-MMT、Organ-MMT、PAN/MMT、APAN/MMT. Effects of preparing conditions of APAN/MMT on adsorption of uranium were investigated. The FT-IR spectra show that the new absorption band at 1653 cm-1( ) appears and the absorption band at 2243 cm-1(-CN) disappears on the spectrum of APAN/MMT, it indicates that the AN and MMT are successfully polymerized by in-situ polymerization and the PAN/MMT is amidoxime functionalized. The APAN/MMT nanocomposite completely lose the X-ray diffraction. The adsorption results show that the obtained APAN-MMT gives uranium adsorption capacity of 3.06 mg.g-1 under following conditions: uranium ion concentration of 10 mg/L, AM mass concentration of 80.0%, initiator of 4.5%, polymerization temperature of 70 ℃，polymerization time of 3 h, pH of 7 and amidoxime functionalized reaction time of 2 h.

Low pressure die casting (LPDC) process of a copper-alloy tap was simulated by the finite element software ProCAST. The casting defect and its reason were analyzed. The optimized design was discussed and the simulation was validated against the low pressure die casting experiment. Results showed that the main defect is misrun and its reason is that the melt solidifies too fast. It’s well solved by increasing the wall thickness of the relational pipe properly. The result agrees with the experiment.

Miscibility of ternary polymer blends composed of poly(ethyleneimine) (PEI), poly(ethylene glycol) (PEG), and carboxymethyl chitosan (CMCS) was investigated by dilute-solution viscometry, FTIR spectrum, and scanning electron microscope (SEM) techniques. The results of these measurements indicate that PEG is immiscible in the ternary CMCS/PEI/PEG polymer blend.

PMMA-b-PDMAEMA/polysulfone composite membranes for CO2 separation was prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization techniques. The chemical composition and structure of the polymers were characterized by Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR), and molecular weight and its distribution were measured by Gel permeation chromatography (GPC). CO2 permeation performance of the PMMA-b-PDMAEMA/ polysulfone composite membranes was test. The results showed that the resulted composited membrane posses good permeation performance for CO2.

Taking “Introduction to Oceanography” as an example, which is the basic course and opened in the colleges covering the major of marine science, this paper discusses how to take the initiative to adapt to the national strategic plan and local economic development in the process of basic education of marine science. According to China's current situation of the marine industry structure, this paper presents that the interface between marine science education and the secondary industry should be strengthened, meanwhile the integration among the basic courses and the actual production and the scientific research should be focused on. Colleges covering the major of marine science should take the initiative to explore training modes to enhance the qualities of talents of different level, and to carry out featured training based on their own characteristics of personnel positioning.