改性水玻璃养护剂的配制及在机场道面中的应用

养护对混凝土道面的强度和耐久性有很大影响。新浇混凝土道面受到外界温度、湿度和风力等作用,在混凝土内部出现湿度梯度,致使水泥水化反应受到影响,产生应力变形和开裂,导致混凝土的强度和耐久性指标下降。笔者在机场施工中,以水玻璃为基材添加其他几种副剂配制成的水泥混凝土养护剂,与混凝土的亲和性较好,喷涂在混凝土表面后,能形成胶状硅酸盐,填充混凝土表层的孔隙,使其硬化,防止和减少表面微裂纹的产生和发展,提高混凝土的强度、抗渗性和耐磨性,对保证施工质量和耐久性很有效。     

A hybrid fuel cell system integrated with methanol steam reformer and methanation reactor

In this paper, a hybrid fuel cell system integrated with methanol steam reformer and methanation reactor is demonstrated. Methanol steam reformer employed in this system is to produce hydrogen-rich reformate in connection with a methanation reactor to reduce the carbon monoxide content effectively, and the reformate gas is sent into a low-temperature polymer electrolyte fuel cell for direct electric power generation. The optimum conditions (temperature, water to methanol ratio, and space velocity) for methanol steam reforming (MSR) reaction and methanation (MET) reaction are verified by experiments. A comparison between pure hydrogen, reformate surrogate, and actual reformate is performed. The results show that the power density of this hybrid system achieves 245.2 mW/cm² while it achieves 268.8 mW/cm² when employing pure hydrogen as the fuel. An alternative novel method to solve the problem of hydrogen storage and transportation is provided and the in-situ hydrogen production and utilizing through low-temperature fuel cell system is realized, which is helpful to accelerate the commercialization process of the fuel cell.     

邯钢烧结配矿结构优化实践

通过研究含铁料基础性能,分析各种配矿结构对烧结过程的影响规律,确定主流矿种及其合理区间,在此基础上,结合综合成本、有害元素、资源库存等因素进行动态优化调整,贯彻稳硅控铝思路,根据生产需要及主流料资源制定更加合理的配矿结构。     

Quantum discord for two-qubit systems in the Bloch channel: effects of longitudinal and transversal relaxation times

Quantum discord is studied for two-qubit systems with different settings under the influence of the Bloch channel which is characterized by the longitudinal and transversal relaxation times and the environmental temperature. The relaxation of the quantum discord strongly depends on the ratio of the two relaxation times and the environmental temperature. It is found that the ratio of the quantum discord to the total correlation becomes finite or zero asymptotically, depending on the ratio of the relaxation times and the system setting. Furthermore, the optimal setting for sharing the quantum discord is discussed for given environmental temperature and ratio of the relaxation times.     

Development of a noble aluminum-pigmented metallic polymer: Recommendations for visible flow and weld line mitigation

We investigated the appearance of flow and weld lines when metallic pigments are used in polymer blends and how such lines can be eliminated by improving the pigment particle shape and optimizing pigment loading. Acrylonitrile butadiene styrene copolymer and two types of aluminum flakes, lamellar and three-dimensional (3D), were blended in a twin-screw extruder with a screw diameter of 25 mm. The temperatures from the hopper to the nozzle were 140, 180, 220, 220, 220, 220, and 220°C. Weld and flow lines were observed using field-emission scanning electron microscopy and energy dispersive X-ray spectroscopy of specially manufactured injection specimens. In the flow line region, traditional lamellar flakes were randomly oriented, while 3D flakes exhibited a distinct and stable orientation. Based on these observations, flow and weld lines in a finished metal/polymer blend can be minimized by using 3D metal particles in place of lamellar flakes. We also investigated the effects of aluminum flake loading on weld and flow line visibility. At low loading, weld lines were clearly visible due to the lack of pigmentation in the front of the polymer flow. Conversely, high loading resulted in relatively high concentrations of pigment near the weld line area, reducing weld line visibility. These findings suggest that there is an optimum metal loading level where the visibility of flow and weld lines is minimized.     

Development of insertion-type peristalsis pump using pneumatic artificial muscles

This study aims to develop a new type of peristaltic pump that transports high-viscosity and solid–liquid mixture fluids. Pumps capable of transporting such fluids are essential in various situations such as factory transportation, outdoors, and emergencies. These fluids are conventionally transported by positive-displacement and rotodynamic pumps. However, solid–liquid fluids could collide with the impeller of the rotodynamic pump and thereby damage the pump, whereas the positive-displacement pump must be sufficiently large to apply high pressure to the transported fluid. A small pump that can transport these fluids would save factory space and enable outdoor applications such as dredging operations. Thus, we adopted earthworm peristalsis as a model mechanism of fluid transport within a standard plumbing infrastructure. The insertion-type peristaltic pump developed in this study uses an artificial rubber muscle to achieve an earthworm-like mechanism. The capability and energy efficiency of the mechanism is evaluated in water transportation experiments.     

Comparative study of proximate composition and amino acid in farmed and wild Pseudobagrus ussuriensis muscles

The proximate composition and amino acid compositions of the muscle of wild and farmed Pseudobagrus ussuriensis were compared. The lipid content of the farmed fish was significantly higher, while moisture content was significantly lower, than those of the wild fish. Pseudobagrus ussuriensis protein has a well‐balanced amino acid composition. The percentages of total amino acids, essential amino acids, nonessential amino acids and delicious amino acids were significantly higher in the wild than those in farmed fish. The ratios of W_EAA to W_TAA (42.78%–43.02%) and W_EAA to W_NEAA (85.52%–87.74%) were comparable to the reference values of 40% and above 60% recommended by FAO/WHO. According to the amino acid scores, methionine would have been described as the first limiting amino acid, and Lys had the highest score for the protein in both wild and farmed Pseudobagrus ussuriensis. This study shows that Pseudobagrus ussuriensis under investigation have high nutritional qualities and are good protein resources.     

Isolation and identification of an antiproliferative substance from fructose–tyrosine Maillard reaction products

We isolated a substance from fructose–tyrosine Maillard reaction products (MRPs) and investigated its antiproliferative effect on six human cancer cell lines. The ethyl acetate fraction of fructose–tyrosine MRPs showed a strong antiproliferative effect; this fraction was isolated and purified using silica gel column chromatography, semipreparative RP-HPLC, and recycling HPLC. The structure of the purified compound was determined using spectroscopic methods. The isolated compound was identified as 2,4-bis(p-hydroxyphenyl)-2-butenal (C₁₆H₁₄O₃, HPB242). HPB242 inhibited cell growth in a dose-dependent manner (10–80 μg/ml) on the six human cancer cell lines. The IC₅₀ values of HPB242 on the six human cancer cell lines were 17.34 μg/ml (MCF-7), 29.21 μg/ml (HCT-116), 34.57 μg/ml (H-460), 34.87 μg/ml (HepG2), 48.77 μg/ml (PC-3), and 55.83 μg/ml (MKN-45).     

Enhanced photocatalytic properties of N–P co-doped TiO<Subscript>2</Subscript> nanosheets with {001} facets

Nitrogen (N) and phosphorus (P) co-doped anatase TiO₂ nanosheets were realized by low-temperature self-doping N–TiO₂ followed by high-temperature P doping with foreign precursor. It is found that P doping process can maintain good TiO₂ nanosheets morphology with exposed {001} facets. Chemical state of dopants indicates that N and P atoms replace O on O sites in TiO₂ lattice. Compared with pure TiO₂ and N-doped TiO₂, N–P co-doped TiO₂ nanosheets exhibits stronger optical absorption and higher degradation rate of dye molecules in visible light regime. The enhanced photocatalytic properties are attributed to two factors. On one hand, N–P co-doping can effectively reduce band gap of TiO₂ from 3.20 to 2.48 eV, leading to an enhancement of the absorption in visible light regime. On the other hand, the presence of exposed {001} facets of TiO₂ nanosheets can induce the effective separation of photogenerated electrons and holes in reaction.     

一种SPH流体仿真边界校正方法

使用光滑粒子流体动力学方法进行流体仿真,并提出一种边界校正方法。使用快速泊松盘采样算法对容器边界进行采样,生成边界粒子,对边界粒子质量进行差值估算,计算边界粒子对流体粒子的作用力,以此来仿真流体与边界的相互作用。该方法可避免穿刺、滞留等现象的发生。通过实验验证了该算法的正确性。