Physical, Chemical Properties and Structural Changes of Zaodan Pickled by Vacuum Decompression Technology

Naxin Sun,Huiping Liu,Xiaowei Zhang,Hongni Wang,Shaojuan Liu,Pei Chen,Weijie Yu,Kai Liu 한국축산식품학회 2018 한국축산식품학회지 Vol.38 No.2

To shorten the production cycle of Zaodan, this study first pickled Zaodan by a novel technology -vacuum decompression technology. Vacuum decompression technology could reduce the pickling time of Zaodan from 20wkto about 9wk.The protein content, moisture and pH of the Zaodan egg white gradually decreased with a concomitant increase in salt during the pickling process. The total sulfhydryl group (SH) group content of the egg white proteins was increased to 2.43×10-3mol/L after being pickled for 30 d, whereas the content of disulphide bonds (SS) was reduced to 23.35×10-3mol/L. The surface hydrophobicity was lowest after pickling for 30 d. In addition, great changes occurred in the secondary structure of the egg white proteins after pickling for 20 d. The disappearance of ovomucin was noticeable based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis.

Boost-type push-pull converter with reduced switches

Gu, Aiyu,Sun, Weijie,Zhang, Guidong,Chen, Sizhe,Wang, Yu,Yang, Ling,Zhang, Yun The Korean Institute of Power Electronics 2020 JOURNAL OF POWER ELECTRONICS Vol.20 No.3

This paper develops and analyses a boost-type push-pull converter with a reduced number of switches. The newly designed converter mainly consists of five diodes, two switches, two inductors, a transformer and two capacitors. By tuning the duty cycle and the transformer ratio, different voltage gains of the proposed converter can be obtained. It is notable for its electrical isolation characteristics. When compared with traditional step-up converters, the step-up module and converter module share the same switch. In addition, the control of the converter becomes easier to implement, and it has better stability and a reduced volume. It should be mentioned that the number of switches in the proposed converter is decreased but maintains the same voltage stress when compared to the traditional structure. The operating principle of proposed converter is demonstrated, which is followed by the design of the component parameters. To validate the feasibility of the proposed topology, an experimental prototype is constructed to verify its correctness and practicability of the proposed converter when compared with the conventional converter.

Preparation of corn straw based spongy aerogel for spillage oil capture

Yuan Li,Xiaodong Liu,Weijie Cai,Yafeng Cao,Yanfeng Sun,Fengzhi Tan 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.5

This work mainly focused on the preparation of a low-cost, ultralight absorbent from renewable corn straw and filter paper via a facile and environmental-friendly approach containing high-shear blending and freeze-drying operation. The physicochemical properties of aerogel were thoroughly examined by several characterization techniques. The satisfactory hydrophobicity of the spongy aerogel was attributed to the formation of polysiloxane on the surface of methyltrimethoxysilane (MTMS) by the silanization reaction. Owing to its superior features, such as ultralow density, high porosity, desirable hydrophobicity, the corn straw based spongy aerogel exhibited a remarkable absorption capacity for both crude oil (36 g/g) and common organic solvents including carbon tetrachloride (CCl4, 45 g/g), dimethyl sulphoxide (DMSO, 24 g/g), N, N-dumethylformamide (DMF, 45 g/g). This might shed light on the design of efficient adsorbent for oil spills and organic pollutants to meet with the sustainable development.

Notoginseng leaf triterpenes ameliorates mitochondrial oxidative injury via the NAMPT-SIRT1/2/3 signaling pathways in cerebral ischemic model rats

Fengwei Nan,Guibo Sun,Xiaobo Sun,Weijie Xie,Ting Zhu,Ping Zhou,Huibo Xu,Xiangbao Meng,Tao Ding The Korean Society of Ginseng 2023 Journal of Ginseng Research Vol.47 No.2

Background: Due to the interrupted blood supply in cerebral ischemic stroke (CIS), ischemic and hypoxia results in neuronal depolarization, insufficient NAD+, excessive levels of ROS, mitochondrial damages, and energy metabolism disorders, which triggers the ischemic cascades. Currently, improvement of mitochondrial functions and energy metabolism is as a vital therapeutic target and clinical strategy. Hence, it is greatly crucial to look for neuroprotective natural agents with mitochondria protection actions and explore the mediated targets for treating CIS. In the previous study, notoginseng leaf triterpenes (PNGL) from Panax notoginseng stems and leaves was demonstrated to have neuroprotective effects against cerebral ischemia/reperfusion injury. However, the potential mechanisms have been not completely elaborate. Methods: The model of middle cerebral artery occlusion and reperfusion (MCAO/R) was adopted to verify the neuroprotective effects and potential pharmacology mechanisms of PNGL in vivo. Antioxidant markers were evaluated by kit detection. Mitochondrial function was evaluated by ATP content measurement, ATPase, NAD and NADH kits. And the transmission electron microscopy (TEM) and pathological staining (H&E and Nissl) were used to detect cerebral morphological changes and mitochondrial structural damages. Western blotting, ELISA and immunofluorescence assay were utilized to explore the mitochondrial protection effects and its related mechanisms in vivo. Results: In vivo, treatment with PNGL markedly reduced excessive oxidative stress, inhibited mitochondrial injury, alleviated energy metabolism dysfunction, decreased neuronal loss and apoptosis, and thus notedly raised neuronal survival under ischemia and hypoxia. Meanwhile, PNGL significantly increased the expression of nicotinamide phosphoribosyltransferase (NAMPT) in the ischemic regions, and regulated its related downstream SIRT1/2/3-MnSOD/PGC-1α pathways. Conclusion: The study finds that the mitochondrial protective effects of PNGL are associated with the NAMPT-SIRT1/2/3-MnSOD/PGC-1α signal pathways. PNGL, as a novel candidate drug, has great application prospects for preventing and treating ischemic stroke.

Design and internal cavitation characteristics of straight-through electric fully enclosed ultra-clean globe valve

Chang Chen,Rui Zhou,Weijie Sun 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.7

The straight-through electric fully closed ultra-clean cut-off valve is a completely closed shut-off valve inside and outside. It relies on magnetic force as the driving force of the valve to control the opening and closing of the valve. In this paper, a new type of cut-off valve structure was designed, a mathematical model was established and its hydrodynamic characteristics were simulated by the computational fluid dynamics method. According to different inlet velocities and different valve openings, the internal cavitation phenomenon of the valve was analyzed. The external magnetic drive control device was designed in combination with the completely closed structure inside and outside the valve, and the magnetic field interference and force of the external permanent magnet and the embedded permanent magnet were studied. This study is helpful for the optimization design and practical engineering application of the ultra-clean valve.

Influence of dragon bamboo with different planting patterns on microbial community and physicochemical property of soil on sunny and shady slopes

Liu Weiyi,Wang Fang,Sun Yanmei,Yang Lei,Chen Huihai,Liu Weijie,Zhu Bin,Hui Chaomao,Wang Shiwei 한국미생물학회 2020 The journal of microbiology Vol.58 No.11

Dragon bamboo (Dendrocalamus giganteus) is a giant sympodial bamboo species widely distributed in Asia. However, it remains unclear how dragon bamboo and soil microbes interact to affect soil properties. In this study, we investigated the planting patterns (semi-natural and artificial) on different slopes (sunny and shady) to determine the effects on soil properties and microbial community. The results showed that the soil in which dragon bamboo was grown was acidic, with a pH value of ~5. Also, the soil organic matter content, nitrogen hydrolysate concentration, total nitrogen, available potassium, and total potassium of the dragon bamboo seminatural forest significantly improved, especially on the sunny slope. In contrast, the available phosphorus level was higher in the artificial bamboo forest, probably owing to the phosphate fertilizer application. The bacterial and fungal diversity and the bacterial abundance were all higher on the sunny slope of the semi-natural forest than those in the other samples. The microbial operational taxonomic units (OTUs) shared between the shady and sunny slopes accounted for 47.8–62.2%, but the core OTUs of all samples were only 24.4– 30.4% of each sample, suggesting that the slope type had a significant effect on the microbial community. Some acidophilic microbes, such as Acidobacteria groups, Streptomyces and Mortierella, became dominant in dragon bamboo forest soil. A PICRUSt analysis of the bacterial functional groups revealed that post-translational modification, cell division, and coenzyme transport and metabolism were abundant in the semi-natural forest. However, some microorganisms with strong stress resistance might be activated in the artificial forest. Taken together, these results illustrated the influence of dragon bamboo growth on soil physicochemical property and microbial community, which might help understand the growth status of dragon bamboo under different planting patterns.

Influence of degree of compaction on electrokinetic remediation of unsaturated soil

Chengwei Yin,Liguo Jiang,Keming Sun,Weiji Sun,Bing Liang 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.4

In order to evaluate the electrokinetic process for unsaturated soil with different compacted conditions, sixremolded soil samples containing the same water content (16 wt%) were compressed to obtain the various degrees ofcompaction (96.87% to 103.37%). All the lab-scale experiments were performed by applying a constant electrical voltage(1 V/cm). The electrical parameters related to the electrokinetic process were monitored to evaluate the influence ofthe soil degree of compaction on this process. The obtained results indicate that the soil compaction degree couldinfluence the electrical current, the migration velocity of the voltage front, and the controlling mechanism of watertransport during the electrokinetic processes. Followed by the initial decline, the electrical current of soil with a lowerdegree of compaction (96.87%) would increase at 0.7mA/h, which was about seven times larger than that of the soilwith a higher degree of compaction (103.37%). The migration velocity of voltage front in the soils increased withdecreasing compaction degree. The voltage front migrated from the cathode towards the anode at 6.66 mm/h in thesoil with a lower degree of compaction (96.87%). In comparison, the migration velocity decreased to 1.75 mm/h in thesoil with a higher degree of compaction (103.37%). Both hydraulic and electrokinetic driving forces could influence thewater transport in unsaturated soil. The results demonstrate that the catholyte entering the soil under the hydraulic gradientcould be opposite to electro-osmosis. The electrokinetic driving force would be a major controlling mechanismfor the unsaturated soil with a higher degree of compaction. For the soil with a lower degree of compaction, thehydraulic driving force would affect the water transport in the soil during its initial saturation period. Moreover, withthe increase in soil saturation, the effects of hydraulic driving force were weakened, and the electrochemical propertiesof the pore solution appeared to be the dominant factor for the electrokinetic process.

Vapour–liquid–solid growth of monolayer MoS₂ nanoribbons

Li, Shisheng,Lin, Yung-Chang,Zhao, Wen,Wu, Jing,Wang, Zhuo,Hu, Zehua,Shen, Youde,Tang, Dai-Ming,Wang, Junyong,Zhang, Qi,Zhu, Hai,Chu, Leiqiang,Zhao, Weijie,Liu, Chang,Sun, Zhipei,Taniguchi, Takaaki,Os Nature Publishing Group UK 2018 Nature Materials Vol.17 No.6

<P>Chemical vapour deposition of two-dimensional materials typically involves the conversion of vapour precursors to solid products in a vapour-solid-solid mode. Here, we report the vapour-liquid-solid growth of monolayer MoS2, yielding highly crystalline ribbons with a width of few tens to thousands of nanometres. This vapour-liquid-solid growth is triggered by the reaction between MoO3 and NaCl, which results in the formation of molten Na-Mo-O droplets. These droplets mediate the growth of MoS2 ribbons in the 'crawling mode' when saturated with sulfur. The locally well-defined orientations of the ribbons reveal the regular horizontal motion of the droplets during growth. Using atomic-resolution scanning transmission electron microscopy and second harmonic generation microscopy, we show that the ribbons are grown homoepitaxially on monolayer MoS2 with predominantly 2H-or 3R-type stacking. Our findings highlight the prospects for the controlled growth of atomically thin nano-structure arrays for nanoelectronic devices and the development of unique mixed-dimensional structures.</P>