Theoretical and experimental investigation of the pressure ratio distribution and the regulation strategy of a two-stage turbocharging system for various altitudes operation

Huiyan Zhang,Xuyang Tang,Liansong Mu,Lei Shi,Kangyao Deng 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.3

Fixed two-stage turbocharging system matched at high altitude leads to engine performance deterioration at low altitudes due to unreasonable pressure ratio distribution between two stages. In this paper, a thermodynamic model of regulated two-stage turbocharging system is established. Theoretical analysis shows the pressure ratio distribution should lean towards a turbocharger with greater efficiency, and the high-altitude operation intensifies the role of HP stage. Experiments are conducted on an environment simulation test bench. Then, the optimal pressure ratio distribution and ETAR at various altitudes are proposed. Experiment results demonstrate that the turbocharging system boosts sufficient intake air with the optimal ETAR. Compared to that with the fixed turbocharging system, the maximum increment of the overall efficiency is 9.3 % at 0 m and attains 1.5 % at 3000 m. Consequently, the output torque is 100 % recovered below 3000 m, and it exceeds 91 % at 4500 m. Moreover, the optimal ETAR reduces the BSFC under low altitude conditions.

The Importance of Allergen Avoidance in High Risk Infants and Sensitized Patients: A Meta-analysis Study

Wu Huiyan,Guo Yuhe,Wang Juan,Zhang Junyan,Zhang Xiaojun,Tao Ailin 대한천식알레르기학회 2014 Allergy, Asthma & Immunology Research Vol.6 No.6

Purpose: At this time, there is uncertainty regarding whether allergen avoidance is the most appropriate strategy for managing or preventing allergies. The purpose of this study was to evaluate the effectiveness of allergen avoidance in the prevention of allergic symptoms in previously sensitized patients and newborns that have the potential to develop allergies. Methods: We performed online searches of articles published from January 1980 to December 2012 in PubMed and The Cochrane Central Register of Controlled Trials, and selected articles involving randomized controlled trials (RCTs) and allergen avoidance. The parameters used to determine allergenic potential in newborns included the risk ratio (RR) of eczema, asthma, rhinitis, wheeze, and cough. The methods employed to evaluate previously sensitized patients were the standardized mean difference (SMD) of forced expiratory volume in 1 second (FEV1) and peak expiratory flow rate (PEFR). Data quality was assessed using the Jadad scale. Results: A total of 14 RCTs were identified. Meta-analysis demonstrated that allergen avoidance for newborns did not reduce the subsequent incidence of allergic diseases (eczema, P=0.21; rhinitis, P=0.3; cough, P=0.1) but significantly reduced the incidence of asthma and wheezing in high-risk infants (asthma, P=0.03; wheeze, P=0.0004). However, previously sensitized patients who reduced their exposure to known allergens did not show improvement in their lung functions (FEV1, P=0.3; PEFR morning, P=0.53; PEFR evening, P= 0.2; PEFR, P=0.29). Conclusions: Allergen avoidance may not always be successful in preventing allergic symptoms. However, rigorous methodological studies are required to confirm this hypothesis.

Comparative analysis of the ovarian transcriptome reveals novel insights into fertility differences in Large White sows

Huiyan Hu,Qing Jia,Bo Zhou,Jing Zhang,Zhiqiang Li,Zhongwu Liu 한국유전학회 2020 Genes & Genomics Vol.42 No.7

Background Fertility is the most important economic trait in sows, as it is critical for profitability. Considerable phenotypic variation in litter size exists in Large White sows. However, relatively little is known about the underlying molecular and genetic bases. Objective An experiment was conducted to screen key genes that affect the fecundity of pigs during the luteal (L) and follicular phases (F) of the estrous cycle. Methods Eight sows (n = 4 for high fertility sows and n = 4 for low fertility sows) were sacrificed on day 14 (day 1 = first day of estrus) after estrus in the L phase. Another eight sows were slaughtered on day 20 of the estrous cycle in the F phase. Sixteen ovarian tissue samples were collected at the different sacrifice time points. Total RNA extracted was used to construct the library and then sequence on an Illumina HiSeq X10 system. Differentially expressed genes (DEGs) between high and low fertility in Large White sows were identified, and their potential biological functions were analyzed using bioinformatics analysis. Results In total, 457 DEGs (161 up-regulated and 296 down-regulated genes) were detected in the ovarian tissues of the high and low fertility groups in the L phase of the estrous cycle. Furthermore, 475 DEGs (253 up-regulated and 222 downregulated genes) were identified in the F phase. Twenty-nine DEGs were common to both comparisons. Kyoto Encyclopedia of Genes and Genomes enrichment analysis showed that the DEGs were mainly associated with steroid biosynthesis, the Hippo signaling pathway, and lysosomes. Others, such as MSMO1, CYP27B1, and CTSB, were related to reproduction. Conclusion These results will contribute to a better understanding of the individual differences in fertility at the transcriptome level, which may provide useful information to explore new ways to improve fertility in pigs.

The establishment of a DNA fifi ngerprinting database for 73 varieties of Lactuca sativa capitate L. using SSR molecular markers

Huiyan Zhou,Penghang Zhang,Jiang Luo,Xueying Liu,Shuangxi Fan,Chaojie Liu,Yingyan Han 한국원예학회 2019 Horticulture, Environment, and Biotechnology Vol.60 No.1

Head lettuce originating near the Mediterranean coast was introduced to China in the fi fth century. It is diffi cult to identifydiff erent varieties of head lettuce due to their close genetic relationships. Simple sequence repeats (SSR) technology is apractical method that has been widely used in variety identifi cation, fi ngerprint construction and genetic diversity analysis. In this paper, 23 pairs of SSR primers were selected to identify and analyse 73 varieties of head lettuce. The results identified a total of 117 mutated alleles detected in 23 loci, with the number of each loci ranging from 2 to 11, with an averageof 5.1 mutated alleles per locus. Additionally, 152 genotypes were detected in 23 loci, with an average of 6.6 genotypes perlocus derived from a range of 2–13. The polymorphism information content ranged from 0.071 to 0.702, with an average of0.499. The selected primer pairs could clearly refl ect the genotypic diversity level of the 73 head lettuce varieties tested, andcan be used in the detection and analysis of the head lettuce varieties. The results of our sequence analysis also showed thatthese 73 varieties of head lettuce could be eff ectively identifi ed by a combination of 19 primer pairs even though the geneticsimilarity among the 73 varieties ranged from 0.647 to 0.991, with an average of 0.798. Based on a capillary electrophoresisplatform, a DNA fi ngerprinting database of 73 head lettuce varieties was established.

Botrytis cinerea hypovirulent strain BcSpd1 induced Panax ginseng defense

Shuhan Zhang,Junyou Han,Ning Liu,Jingyuan Sun,Huchen Chen,Jinglin Xia,Huiyan Ju,Shouan Liu 고려인삼학회 2023 Journal of Ginseng Research Vol.47 No.6

Background: Gray mold, caused by Botrytis cinerea, is one of the major fungal diseases in agriculture. Biological methods are preferred over chemical fungicides to control gray mold since they are less toxicto the environment and could induce the resistance to pathogens in plants. In this work, we try tounderstand if ginseng defense to B. cinerea could be induced by fungal hypovirulent strain △BcSpd1. BcSpd1 encodes Zn(II)2Cys6 transcription factor which regulates fungal pathogenicity and we recentlyreported △BcSpd1 mutants reduced fungal virulence. Methods: We performed transcriptomic analysis of the host to investigate the induced defense responseof ginseng treated by B. cinerea △BcSpd1. The metabolites in ginseng flavonoids pathway were determinedby UPLC-ESI-MS/MS and the antifungal activates were then performed. Results: We found that △BcSpd1 enhanced the ginseng defense response when applied to healthyginseng leaves and further changed the metabolism of flavonoids. Compared with untreated plants, theapplication of △BcSpd1 on ginseng leaves significantly increased the accumulation of p-coumaric acidand myricetin, which could inhibit the fungal growth. Conclusion: B. cinerea△BcSpd1 could effectively induce the medicinal plant defense and is referred to asthe biological control agent in ginseng disease management.

Does Industrial Policy Boost Corporate Cash Holdings?

Lili Wang,Huiyan Zhang 동아시아무역학회 2021 Journal of East Asian Trade(JEAT) Vol.3 No.2

Purpose – The purpose of this paper is proving that industrial policies promote corporate cash holdings due to the effective governance effect, which enriched the research on the influencing factors of cash holdings and the consequences of industrial policies. Design/Methodology/Approach – Based on the panel of A-share listed companies in Shanghai and Shenzhen stock markets from 2007 to 2019, the empirical evidence have researched the relationship of industrial policy and the cash hold of listed companies. Findings – This paper studies the relationship of industrial policy and the cash hold of listed companies. It is found that t the positive effect of industrial policy on cash holding is mainly due to the fact that industrial policy inhibits management’s excessive investment and perquisite consumption, and thus alleviates the “dissipative hypothesis” of cash holding. Research Implications – In the management of this paper, China attaches great importance to economic regulation by industrial policies. As an important form of economic regulation by the government, industrial policy plays a role in guiding the flow of social capital and optimizing the allocation of resources, thus promoting the adjustment of industrial structure and promoting economic transformation and upgrading.

Preparation and Performance Study of Self-Cleaning TiO2/Kaolin-Finished Cotton Fabric

Qiang Zhao,Yunting Zhang,Zhenjiang Liu,Huiyan Ma,Yan Li,Xiaoping Gao 한국섬유공학회 2023 Fibers and polymers Vol.24 No.12

TiO2/kaolin was first synthesized by using ultrasound-sol–gel method and then deposited onto the surface of cotton fabrics through two dipping and two rolling process. To investigate the properties of this TiO2/kaolin-finished cotton fabric, TiO2/kaolin/cotton composites were characterized by Fourier transform infrared spectrum and energy dispersive spectrometer, while the surface morphologies of the cotton fabrics were analyzed by field emission scanning electron microscopy. The whiteness, air permeability, breaking strength and elongation of TiO2/kaolin/cotton composites were, respectively, measured and the results showed that all these parameters decreased slightly with the appearance of TiO2/kaolin. The UPF value of TiO2/kaolin/cotton composites was significantly enhanced to 100+ , even if after soaping for 30 times, which might be due to the synergistic effect of kaolin and TiO2. In addition, the performance such as hand feel attributes, softness, smoothness and stiffness were measured by PhabrOmeter, respectively. The stiffness of all finished fabrics was obviously better than that of the unfinished cotton. However, the softness and smoothness of finished fabrics were slightly decreased compared to unfinished cotton. Rhodamine B was used as a test contaminant to qualitatively assess the self-cleaning properties of the TiO2/kaolin-finished cotton fabric. The removal of Rhodamine B indicated that the TiO2/kaolin-finished fabric exhibited excellent photocatalytic properties. This study illustrates the great potential of the low-cost kaolin powder as an efficient finishing agent for the fabric finishing process, and meanwhile provides a novel suggestion for fabric modification.

Research on Seismic Scenario Simulation Method in Urban System

Jianfei Wang(王建飞,),Huiyan Wang(王慧彦),Jingfa Zhang(张,景发,),Qiang Li(李强) 위기관리 이론과 실천 2020 Disastronomy Vol.3 No.1

Earthquake was called The Head of Catastrophe in many countries because of its sudden, wide-ranging, and severe loss characteristics. Due to the density of people, economy and buildings in cities, the development and evolution of the earthquake disaster chain presents more complex and varied systemic features. There have been many studies of seismic scenarios, most of which focus on the simulation of the disaster itself, but little attention has been paid to the disaster mechanism and its control methods within the urban system. In the view of urban systemic characteristics, this paper analyzes the evolution and development of earthquake disaster scenarios in urban systems. Based on the interaction of various elements of the urban system, the content system of urban seismic scenario research is clarified. Finally, considering the dual scenarios of disaster and response, an urban seismic scenario construction method is proposed which covers risk assessment, disaster simulation, task and capability matching, emergency preparedness plan. We hope that this research can develop the urban earthquake scenario research and provide reference for the earthquake disaster reduction.

Synbiotic of Pediococcus acidilactici and Inulin Ameliorates Dextran Sulfate Sodium-Induced Acute Ulcerative Colitis in Mice

( Mingzhu Wang ),( Longzhou Zhang ),( Huiyan Piao ),( Yuanming Jin ),( Chengdu Cui ),( Xin Jin ),( Lianhua Cui ),( Chunri Yan ) 한국미생물생명공학회 2024 Journal of microbiology and biotechnology Vol.34 No.3

Colitis is a major gastrointestinal disease that threatens human health. In this study, a synbiotic composed of inulin and Pediococcus acidilactici (P. acidilactici) was investigated for its ability to alleviate dextran sulfate sodium (DSS)-induced colitis. The results revealed that the synbiotic, composed of inulin and P. acidilactici, attenuated the body weight loss and disease activity index (DAI) score in mice with DSS-mediated colitis. Determination of biochemical indicators found that the synbiotic increased anti-oxidation and alleviated inflammation in mice. Additionally, histopathological examination revealed that colonic goblet cell loss and severe mucosal damage in the model group were significantly reversed by the combination of inulin and P. acidilactici. Moreover, synbiotic treatment significantly reduced the levels of IL-1β, TNF-α, and IL-6 in the serum of mice. Thus, a synbiotic composed of inulin and P. acidilactici has preventive and therapeutic effects on DSS-induced colitis in mice.

A mathematical description of thermal decomposition and spontaneous ignition of wood slab under a truncated-cone heater

Dekui Shen,Qian Liu,Rui Xiao,Huiyan Zhang,Mengxiang Fang 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.3

A mathematical model of thermal decomposition together with the flammability limit is proposed to describe the pyrolysis and spontaneous ignition of wood slab subjected to the radiation from a truncated-cone heater. The prominent physical and chemical phenomena were considered in the model, involving heat transfer in a solid, heat consumed by thermal decomposition reactions, the evaporation of moisture, re-radiation from pore surfaces inside a solid and so on. The numerical solution allows the prediction of in-depth temperature profiles, evolution of volatiles,variation of thermal conductivity, apparent mass loss (solid conversion) and ignition time. The different densities for wood species and effect of moisture content and grain orientation on thermal conductivity are also considered in the model, producing a good prediction of surface temperatures. This gives birth to the reasonable prediction on ignition time of wood by employing fixed surface temperature (400 oC) as ignition criterion. However, the analysis of constituent fractions for the species associated with the multi-components kinetic scheme should be included in the mathematical model to give a more precise prediction on the apparent mass loss of solid.