NUMERICAL STUDY ON CAVITATION FLOW CHARACTERISTICS IN DIESEL FUEL INJECTOR CONTROL VALVE

Zhenming Liu,Jingbin Liu,Jiechang Wu,Xiaolei Gu 한국자동차공학회 2022 International journal of automotive technology Vol.23 No.4

The flow and cavitation in the flow passage of the control valve are calculated, and the effects of operating conditions (including injection pulse width, rail pressure and ball valve lift) on the flow and cavitation characteristics are analyzed under dynamic boundary conditions. The simulation results show that the cavitation in the outflowing control-orifice (OA) and the guide-hole are almost unaffected by these operating conditions. In contrast, the cavitation process in the ball valve chamber has two distinct stages, which can be classified as violent and relatively smooth. The shorter the pulse width, the more severe the average degree of cavitation in the ball valve chamber; however, the risk of cavitation erosion on the ball valve and the ball valve seat surface does not increase too much. The increase of rail pressure and the increase of ball valve lift will aggravate the cavitation, and the cavitation position will move forward closer to the sealing annular surface.

A Facile Process Combined with Electroless Deposition and Hydrophobic Treatment to Fabricate Self-cleaning Radiation Protection Suits for Pregnant Woman

Wenya Liu,Di Sun,Haodong Ma,Zhenming Chen,Chengmei Gui,Junjun Huang 한국섬유공학회 2022 Fibers and polymers Vol.23 No.5

Silver-printed terylene is presented to fabricate anti-electromagnetic radiation Maternity Dress (AMD) withsuperior shielding effectiveness, but the use of noble metal as electromagnetic interference shielding materials enhances costof raw material and restricts its application. In this study, a facile process combined with electroless deposition andhydrophobic treatment to fabricate self-cleaning radiation protection cotton for AMD was established. The active groups onthe plant fiber surface could absorb Sn2+ and Pd2+ through coordination effect, acting as catalytic center, which can catalyzethe reduction of Ni2+ in the plating solution. Ni particle deposited on the its surface with deposited amount of 32 %. Thefabricated material exhibited an shielding effectiveness of 52.5 dB and it meet AMD criteria. Owing to the cooperation of thelow surface energy and rough structure of precipitation, the Ni-plated cotton modified with (3-Mercaptopropyl)trimethoxysilane exhibited remarkable hydrophobicity with water contact angle up to 112.8 o and excellent self-cleaningproperty.

Infection of Oligochaetes, Limnodrilus hoffmeisteri (Annelida: Oligochaeta), in the Nasal Cavity of a Chinese Man

Hongbin Liu,Zhenming Zhang,Guangping Huang,Xiaolong Gu,Chunmiao Wang,Yan Wang,Zhimin Lu 대한기생충학열대의학회 2017 The Korean Journal of Parasitology Vol.55 No.1

Seasonal changes in soil acidity and related properties in ginseng artificial bed soils under a plastic shade

You, Jiangfeng,Liu, Xing,Zhang, Bo,Xie, Zhongkai,Hou, Zhiguang,Yang, Zhenming The Korean Society of Ginseng 2015 Journal of Ginseng Research Vol.39 No.1

Background: In Changbai Mountains, Panax ginseng (ginseng) was cultivated in a mixture of the humus and albic horizons of albic luvisol in a raised garden with plastic shade. This study aimed to evaluate the impact of ginseng planting on soil characteristics. Methods: The mixed-bed soils were seasonally collected at intervals of 0-5 cm, 5-10 cm, and 10-15 cm for different-aged ginsengs. Soil physico-chemical characteristics were studied using general methods. Aluminum was extracted from the soil solids with $NH_4Cl $(exchangeable Al) and Na-pyrophosphate (organic Al) and was measured with an atomic absorption spectrophotometer. Results: A remarkable decrease in the pH, concentrations of exchangeable calcium, $NH_4^+$, total organic carbon (TOC), and organic Al, as well as a pronounced increase in the bulk density were observed in the different-aged ginseng soils from one spring to the next. The decrease in pH in the ginseng soils was positively correlated with the $NH_4^+$ (r=0.463, p<0.01), exchangeable calcium (r=0.325, p<0.01) and TOC (r= 0.292, p < 0.05) concentrations. The $NO_3^-$ showed remarkable surface accumulation (0-5 cm) in the summer and even more in the autumn but declined considerably the next spring. The exchangeable Al fluctuated from $0.10mg\;g^{-1}$ to $0.50mg\;g^{-1}$ for dry soils, which was positively correlated with the $NO_3^-$ (r=0.401, p < 0.01) and negatively correlated with the TOC (r=-0.329, p < 0.05). The Al saturation varied from 10% to 41% and was higher in the summer and autumn, especially in the 0-5 cmand 5-10 cm layers. Conclusion: Taken together, our study revealed a seasonal shift in soil characteristics in ginseng beds with plastic shade.

Changes in element accumulation, phenolic metabolism, and antioxidative enzyme activities in the red-skin roots of Panax ginseng

Ying Zhou,Zhenming Yang,Lingling Gao,Wen Liu,Rongkun Liu,Junting Zhao,Jiangfeng You 고려인삼학회 2017 Journal of Ginseng Research Vol.41 No.3

Background: Red-skin root disease has seriously decreased the quality and production of Panax ginseng (ginseng). Methods: To explore the disease’s origin, comparative analysis was performed in different parts of the plant, particularly the epidermis, cortex, and/or fibrous roots of 5-yr-old healthy and diseased red-skin ginseng. The inorganic element composition, phenolic compound concentration, reactive oxidation system, antioxidant concentrations such as ascorbate and glutathione, activities of enzymes related to phenolic metabolism and oxidation, and antioxidative system particularly the ascorbateeglutathione cycle were examined using conventional methods. Results: Aluminum (Al), iron (Fe), magnesium, and phosphorus were increased, whereas manganese was unchanged and calcium was decreased in the epidermis and fibrous root of red-skin ginseng, which also contained higher levels of phenolic compounds, higher activities of the phenolic compound-synthesizing enzyme phenylalanine ammonia-lyase and the phenolic compound oxidation-related enzymes guaiacol peroxidase and polyphenoloxidase. As the substrate of guaiacol peroxidase, higher levels of H2O2 and correspondingly higher activities of superoxide dismutase and catalase were found in red-skin ginseng. Increased levels of ascorbate and glutathione; increased activities of L-galactose 1-dehydrogenase, ascorbate peroxidase, ascorbic acid oxidase, and glutathione reductase; and lower activities of dehydroascorbate reductase, monodehydroascorbate reductase, and glutathione peroxidase were found in red-skin ginseng. Glutathione-S-transferase activity remained constant. Conclusion: Hence, higher element accumulation, particularly Al and Fe, activated multiple enzymes related to accumulation of phenolic compounds and their oxidation. This might contribute to red-skin symptoms in ginseng. It is proposed that antioxidant and antioxidative enzymes, especially those involved in ascorbateeglutathione cycles, are activated to protect against phenolic compound oxidation.

Effects of Supplementary Chinese Milk Vetch Silage and Rapeseed Meal on the Performance and Rumen Fermentation of Lambs Given Ammoniated Rice Straw Based Diet

Wu, Yueming,Liu, Jian Xin,Chen, Zhenming Asian Australasian Association of Animal Productio 1998 Animal Bioscience Vol.11 No.4

This study was proposed to investigate effects of inclusion of Chinese milk vetch silage (MVS) and rapeseed meal (RSM) on the growth and rumen fermentation of Hu-sheep. Fifty weanling lambs were randomly divided into five equal groups and offered ammoniated rice straw (ABRS) ad libitum along with 100 g concentrate (Trial 1). The animals in $T_0$, $T_1$, $T_2$, $T_3$ and $T_4$ group were respectively supplemented with MVS at levels of 0, 0, 7, 14 or 21% and with RSM at levels of 0, 15, 10, 5 or 0%. Daily gain of lambs was significantly (p<0.05) higher in $T_1$, $T_2$ and $T_3$ group than that in $T_0$ and $T_4$ group. Feed conversion ratio was greatly reduced in supplemented groups as compared with $T_0$ group. In trial 2, five sheep with rumen cannulae were used in a $5{\times}5$ Latin square design. The experimental treatments were as described in Trial 1, but without concentrate. The intake of AVRS was significantly (p<0.05) lower in $T_4$ group than that in $T_0$ group, and also significantly (p<0.05) lower than those in $T_1$ and $T_2$ group. Little difference among all treatments was found in 48h DM degradability of ABRS, MVS and RSM, and in rumen pH value and microbial protein concentration. Rumen concentrations of individual and total VFA tended to be higher in supplemented groups than those in $T_0$ group.These rusults suggest that supplementation with RSM or RSM plus MVS can effectively improve the performance of lambs, and may fail to influence markedly the rumen digestion of ABRS and rumen environments.

Seasonal changes in soil acidity and related properties in ginseng artificial bed soils under a plastic shade

Jiangfeng You,Xing Liu,Bo Zhang,Zhongkai Xie,Zhiguang Hou,Zhenming Yang 고려인삼학회 2015 Journal of Ginseng Research Vol.39 No.3

Background: In Changbai Mountains, Panax ginseng (ginseng) was cultivated in a mixture of the humus and albic horizons of albic luvisol in a raised garden with plastic shade. This study aimed to evaluate the impact of ginseng planting on soil characteristics. Methods: The mixed-bed soils were seasonally collected at intervals of 0-5 cm, 5-10 cm, and 10-15 cm for different-aged ginsengs. Soil physico-chemical characteristics were studied using general methods. Aluminum was extracted from the soil solids with NH₄Cl (exchangeable Al) and Na-pyrophosphate (organic Al) and was measured with an atomic absorption spectrophotometer. Results: A remarkable decrease in the pH, concentrations of exchangeable calcium, NH₄⁺, total organic carbon (TOC), and organic Al, as well as a pronounced increase in the bulk density were observed in the different-aged ginseng soils from one spring to the next. The decrease in pH in the ginseng soils was positively correlated with the NH⁺₄ (r=0.463, p<0.01), exchangeable calcium (r=0.325, p<0.01) and TOC (r = 0.292, p < 0.05) concentrations. The NO₃ showed remarkable surface accumulation (0-5 cm) in the summer and even more in the autumn but declined considerably the next spring. The exchangeable Al fluctuated from 0.10 mg g<SUP>-1</SUP> to 0.50 mg g<SUP>-1</SUP> for dry soils, which was positively correlated with the NO₃ (r=0.401, p < 0.01) and negatively correlated with the TOC (r=-0.329, p < 0.05). The Al saturation varied from 10% to 41% and was higher in the summer and autumn, especially in the 0-5 cmand 5-10 cm layers. Conclusion: Taken together, our study revealed a seasonal shift in soil characteristics in ginseng beds with plastic shade.

Failure Analyses of a Reinforced Embankment by Strength Reduction and Limit Equilibrium Methods Considering Hardening of Soft Clay

Jianfeng Chen,Junxiu Liu,Jianfeng Xue,Zhenming Shi 대한토목학회 2014 KSCE JOURNAL OF CIVIL ENGINEERING Vol.18 No.7

A 7.6 m high reinforced embankment-wall system was constructed in stages on very thick soft clay. The reinforced structure incurred a deep-seated global failure at the end of backfill loading. The Strength Reduction Method (SRM) and the Limit Equilibrium Method (LEM) were employed to analyze the stability of the structure. It was found that the SRM captured the deep-seated global failure of the structure through a coupled mechanical and hydraulic Finite Element (FE) modeling. The stability of the reinforced structure was much underestimated or overestimated by the LEM using unconsolidated-undrained or consolidated-undrained shear strength values. However, the stability of the structure could be still captured by the LEM with the increased shear strength values assigned to the consolidated zone directly beneath the reinforced structure and with the unconsolidated-undrained shear strength values assigned to the unconsolidated zone beyond the structure. In practice, both the SRM and the LEM are recommended for stability analyses of geosynthetic-reinforced structures on soft ground considering hardening of the soil so that the results from the two methods can be cross-examined.

Seasonal changes in soil acidity and related properties in ginseng artificial bed soils under a plastic shade

Jiangfeng You,Xing Liu,Bo Zhang,Zhongkai Xie,Zhiguang Hou,Zhenming Yang 고려인삼학회 2015 Journal of Ginseng Research Vol.39 No.1

Background: In Changbai Mountains, Panax ginseng (ginseng) was cultivated in a mixture of the humusand albic horizons of albic luvisol in a raised garden with plastic shade. This study aimed to evaluate theimpact of ginseng planting on soil characteristics. Methods: The mixed-bed soils were seasonally collected at intervals of 0e5 cm, 5e10 cm, and 10e15 cmfor different-aged ginsengs. Soil physico-chemical characteristics were studied using general methods. Aluminum was extracted from the soil solids with NH4Cl (exchangeable Al) and Na-pyrophosphate(organic Al) and was measured with an atomic absorption spectrophotometer. Results: A remarkable decrease in the pH, concentrations of exchangeable calcium, NH4þ, total organiccarbon (TOC), and organic Al, as well as a pronounced increase in the bulk density were observed in thedifferent-aged ginseng soils from one spring to the next. The decrease in pH in the ginseng soils waspositively correlated with the NHþ4 (r¼0.463, p<0.01), exchangeable calcium (r¼0.325, p<0.01) and TOC(r ¼ 0.292, p < 0.05) concentrations. The NO3 showed remarkable surface accumulation (0e5 cm) in thesummer and even more in the autumn but declined considerably the next spring. The exchangeable Alfluctuated from 0.10 mg g1 to 0.50 mg g1 for dry soils, which was positively correlated with the NO3(r ¼ 0.401, p < 0.01) and negatively correlated with the TOC (r¼0.329, p < 0.05). The Al saturation variedfrom 10% to 41% and was higher in the summer and autumn, especially in the 0e5 cmand 5e10 cm layers. Conclusion: Taken together, our study revealed a seasonal shift in soil characteristics in ginseng bedswith plastic shade.

Changes in element accumulation, phenolic metabolism, and antioxidative enzyme activities in the red-skin roots of Panax ginseng

Zhou, Ying,Yang, Zhenming,Gao, Lingling,Liu, Wen,Liu, Rongkun,Zhao, Junting,You, Jiangfeng The Korean Society of Ginseng 2017 Journal of Ginseng Research Vol.41 No.3

Background: Red-skin root disease has seriously decreased the quality and production of Panax ginseng (ginseng). Methods: To explore the disease's origin, comparative analysis was performed in different parts of the plant, particularly the epidermis, cortex, and/or fibrous roots of 5-yr-old healthy and diseased red-skin ginseng. The inorganic element composition, phenolic compound concentration, reactive oxidation system, antioxidant concentrations such as ascorbate and glutathione, activities of enzymes related to phenolic metabolism and oxidation, and antioxidative system particularly the ascorbate-glutathione cycle were examined using conventional methods. Results: Aluminum (Al), iron (Fe), magnesium, and phosphorus were increased, whereas manganese was unchanged and calcium was decreased in the epidermis and fibrous root of red-skin ginseng, which also contained higher levels of phenolic compounds, higher activities of the phenolic compound-synthesizing enzyme phenylalanine ammonia-lyase and the phenolic compound oxidation-related enzymes guaiacol peroxidase and polyphenoloxidase. As the substrate of guaiacol peroxidase, higher levels of $H_2O_2$ and correspondingly higher activities of superoxide dismutase and catalase were found in red-skin ginseng. Increased levels of ascorbate and glutathione; increased activities of $\text\tiny L$-galactose 1-dehydrogenase, ascorbate peroxidase, ascorbic acid oxidase, and glutathione reductase; and lower activities of dehydroascorbate reductase, monodehydroascorbate reductase, and glutathione peroxidase were found in red-skin ginseng. Glutathione-S-transferase activity remained constant. Conclusion: Hence, higher element accumulation, particularly Al and Fe, activated multiple enzymes related to accumulation of phenolic compounds and their oxidation. This might contribute to red-skin symptoms in ginseng. It is proposed that antioxidant and antioxidative enzymes, especially those involved in ascorbate-glutathione cycles, are activated to protect against phenolic compound oxidation.