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1

Simultaneous determination of multiple components in Fuke Yangrong pill by HPLC

Wang Hua, Zhan Changjuan, Wang Yi

Acta Chromatographica

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2023

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Vol. 35, no. 4

326--330

EN

Fuke Yangrong pill, a traditional Chinese patent medicine, with the functions of nourishing qi and blood, soothing liver and relieving depression, regulating menstruation and removing blood stasis, is composed of 16 Chinese medicinal herbs. For quality control purpose, an HPLC method was established for simultaneous quantification of paeoniflorin, hesperidin and ligustilide in Fuke Yangrong pill. With acetonitrile-0.1% formic acid as mobile phase, gradient elution was carried out using Agilent ZORBAX Eclipse Plus C18 column (250 mm × 4.6 mm, 5.0 μm) at 1.0 mL min⁻¹. Detection wavelength was set at 230 nm for paeoniflorin, 280 nm for hesperidin and ligustilide. The temperature was 30 °C. There was a good linearity between the peak area and the concentration of each component to be measured within their linear range (r ≥ 0.9994). The average recoveries were between 98.6% and 102.6% with RSDs no more than 2.93%. This method was validated to be accurate and convenient, which is suitable for the quality control of Fuke Yangrong pill.

2

Effect of the foaming performance of ammonium dibutyl dithiophosphate on the flotation of slime-containing copper sulfide ore

Deng Rongdong, Duan Wenting, Wang Yi, Hu Yuan

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 153492

EN

The use of ammonium dibutyl dithiophosphate (ADD) as a collector in the flotation of slimecontaining copper sulfide ore typically produces a sticky froth, which results in poor flotation. The mechanism and effects of copper sulfide ore flotation in synergistic systems comprising ADD and terpenic oil reagents have been systematically investigated to solve this problem. A high ratio of ADD to terpenic oil is not conducive to the flotation of fine-grained copper sulfide ores; however, adjusting this ratio may improve floatation by reducing the effect of the slime. Lowering the ratio from 5:1 to 1:1 increased the copper grade from 17.7% to 20.8%, while the recovery was largely unchanged. Notably, adjusting this ratio also reduced the cost of the flotation reagent. To study the mechanism by which the ADD–to–terpenic oil ratio affects the foam performance, the froth stability tests of the gas–liquid twophase and gas–liquid–solid three-phase systems were performed. Reducing the proportion of ADD reduced the froth water content and weakened the ability of the froth to collect gangue by adsorbtion with copper ions; this reduced gangue entrainment and maximized recovery and product quality.

3

High-Performance Workwear for Coal Miners in Northern China: Design and Performance Evaluation

Ke Ying, Zheng Qing, Wang Faming, Wang Min, Wang Yi

Autex Research Journal

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2022

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Vol. 22, no. 2

155--162

EN

The design of workwear has significant effects on worker performance. However, the current workwear for coal miners in Northern China is poor in fitness and thermal comfort. In this study, new workwear (NEW) for coal miners was developed with the design features providing better cold protection and movement comfort performance, as compared with a commonly worn workwear (CON). To evaluate the effectiveness of NEW, we conducted human trials which were performed using simulated work movements (i.e., sitting, shoveling, squatting, and crawling) in a climate chamber (10°C, 75% RH). Physiological measurements and perceptual responses were obtained. The results demonstrated that the local skin temperatures at chest, scapula, thigh, and calf; mean skin temperatures,; and thermal comfort in NEW were significantly higher than those in CON. NEW also exerted an improvement in enhancing movement comfort. We conclude that NEW could meet well with the cold protective and mobility requirements.

4

On the Estimation of Fatigue Crack Initiation Life of H62 Brass

Zheng M., Zhang S., Peng Xiao Jian, Wang Yi

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 1

31--35

EN

In the present paper, the excavation of the energetic approach that estimates the fatigue crack initiation life of metal is conducted for H62 brass. The benefit of the energetic approach is the division of the actual applied strain range Δε into two parts, that is, a damage strain range Δεd that induces fatigue damage within the metal, and an undamaged strain range Δεc, which does not produce fatigue damage of the metal and corresponds to theoretical strain fatigue limit. The brightness of this approach is that the undamaged strain range Δεc can be estimated by the fundamental conventional parameters of metal in tensile test. The result indicated that the fatigue crack initiation life of H62 brass can be estimated by this approach successfully.

5

The effect of freeze-thaw cycles on flexural behaviour of FRP-reinforced ECC beams

Wang Yi, Wang Guan, Guan Zhongwei, Ashour Ashraf, Ge Wenjie, Zhang Pu, Lu Weigang, Cao Dafu

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 3

265--288

EN

This paper presents experimental and theoretical investigations on the flexural utilised of FRP (fibre-reinforced polymer) rebar-reinforced ECC (engineered cementitious composite) beams subjected to freeze–thaw cycles. Eight FRP-reinforced specimens after subjected to 0, 50, 100 and 150 cycles of freeze–thaw were tested to failure under flexural loading. Experimental results show that the moment capacity decreases with the increase of freeze–thaw cycles regardless of the material used, but the decreasing rate of the reinforced ECC specimen is lower than that of the conventional reinforced concrete specimen. The bearing capacity, deflection and crack width of the reinforced ECC specimens under quasi-permanent combination of moments are 1.13 ~ 1.21, 0.66 ~ 0.90 and 0.71 times of those of the conventional reinforced concrete specimens, respectively. Due to the excellent tensile and durability performance of ECC materials, bearing capacity, stiffness and crack resistance of FRP-reinforced ECC beams are enhanced compared with their conventional counterparts, particularly with more freeze–thaw cycles. Based on the formulae from ACI 440 and GB 50608, taking into account of the contribution of ECC material and balanced reinforcement ratio, the simplified formulae are developed to estimate the moment capacity and stiffness of the FRP-reinforced ECC beams. The results predicted on the moment capacity and deflection are in good agreement with the corresponding experimental measurements.

6

Influence of Wave-Absorbing Functional Particles on the Electromagnetic Properties and Mechanical Properties of Coated Composites for Nickel Powders

Liu Yuanjun, Wang Yi, Wu Xiang, Zhang Lulu, Niu Jiarong

Fibres & Textiles in Eastern Europe

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2020

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Vol. 28, no. 5 (143)

75--81

EN

In this subject, a single-layer coated composite for nickel powders was prepared using PU2540 polyurethane as the matrix, nickel powder as the wave-absorbing functional particle, and coating technology on plain cotton fabric. The influence of wave-absorbing functional particles on the dielectric, shielding effectiveness and mechanical properties of the single-layer coated composite for nickel powders was mainly analysed and compared. Results showed that the real and imaginary parts and loss tangent of the dielectric constant were all the largest when the iron powder was mixed with the nickel powder, and its polarizing ability, loss ability and attenuation ability with respect to electromagnetic waves were all the maximum. When the graphene was mixed with the nickel powder, the shielding attenuation ability with respect to electromagnetic waves was the best.

PL

W ramach pracy przygotowano jednowarstwowy kompozyt powlekany żywicą poliuretanową zawierającą proszek niklu. Do przygotowania kompozytów użyto poliuretanu PU2540 jako matrycy i proszku niklu jako absorbującej fale cząstki funkcjonalnej oraz zastosowano technologię powlekania na gładkiej tkaninie bawełnianej. Przeanalizowano i porównano głównie wpływ absorbujących fale funkcjonalnych cząstek na dielektryk, skuteczność ekranowania i właściwości mechaniczne jednowarstwowego powlekanego kompozytu. Wyniki pokazały, że rzeczywiste i urojone części oraz styczna strat stałej dielektrycznej były największe, gdy proszek żelaza został zmieszany z proszkiem niklu, a jego zdolność polaryzacyjna, zdolność do strat i zdolność tłumienia fal elektromagnetycznych były maksymalne. Gdy grafen został zmieszany z proszkiem niklu, zdolność tłumienia ekranowania fal elektromagnetycznych była najlepsza.