Steam-Chest Molding of Expanded Polypropylene Foams. 2. Mechanism of Interbead Bonding

Zhai, Wentao,Kim, Young-Wook,Jung, Dong Won,Park, Chul B. American Chemical Society 2011 INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH - Vol.50 No.9

<P>Expanded polypropylene (EPP) bead foams were processed using steam-chest molding. Interbead bonds formed during processing and was characterized by observing both the product surface and the fracture surfaces using scanning electron microscopy (SEM) and by measuring the tensile properties of specimens. It was found that both the degree of interbead bonding and the tensile strength had a direct relationship to the steam pressure/temperature and that high steam temperature enhanced the crystallization behavior of EPP beads during the cooling process. A formation mechanism of interbead bonding during processing was proposed based on the crystal melting behaviors, as discussed in the first article of this series (<name name-style='western'>Zhai</name> et al. Ind. Eng. Chem. Res.<x xml:space='preserve'> </x>2010<x xml:space='preserve'>, </x>49<x xml:space='preserve'>, </x>9822). Possible parameters influencing the formation of interbead bonding, namely, steam temperature/pressure and bead foam expansion ratio, were investigated in this study. The effect of postannealing of the EPP products on the shrinkage and crystallinity of the molded EPP products was also addressed.</P>

One-pot synthesis of hybrid mesoporous xerogels starting with linear polymethylhydrosiloxane and bridged bis-(trimethoxysilyl)ethane

Zhai, Shang-Ru,Song, Yu,Zhai, Bin,An, Qing-Da,Ha, Chang-Sik Elsevier 2012 Microporous and mesoporous materials Vol.163 No.-

Genetic and antigenic characterization of fragments of the pheasant immunoglobulin Y heavy chain constant region

Jing Zhai,Weishan Chang,Zhenzhen Zhai,Xingliang Ma,Lingling Yang,Jinfeng Ti,Daozhen Song,Shijun Fu,Dapeng Li 한국유전학회 2016 Genes & Genomics Vol.38 No.8

Few studies have attempted to characterize the pheasant (Phasianus colchicus) immunoglobulin Y (IgY) heavy chain constant region. In the present study, fragments of the pheasant IgY heavy chain constant region were cloned, analyzed, and expressed. The cross-reactivity of IgY or immunoglobulin G (IgG)s with antigens from other vertebrate species was determined using dot-enzymelinked immunosorbent assay and western blot analysis. Five peptides of the pheasant IgY heavy chain constant region were synthesized to determine its immunoregulatory activity in vitro. The IgY heavy chain constant region from pheasant showed the highest homology with that from chicken (71.2 %) and duck (49.1 %). Phylogenetic analysis for IgY showed that pheasant was closely related to chicken and duck than to any other analyzed vertebrate species. The rabbit anti-chicken IgG showed immunologic cross-reactivity with recombinant proteins of the pheasant IgY heavy chain constant region. Four peptides were able to induce significant up-regulation of interleukin (IL)-1b, IL-4, and interferon-c in chicken peripheral blood lymphocytes, suggesting a new role of avian IgY in immune regulation.

Analysis of Active Components and Proteomics of Chinese Wild Rice (Zizania latifolia (Griseb) Turcz) and Indica Rice (Nagina22)

Ming-xia Jiang,Li-jie Zhai,Hua Yang,Shu-menghui Zhai,Cheng-kai Zhai 한국식품영양과학회 2016 Journal of medicinal food Vol.19 No.8

The ancient Chinese wild rice (Zizania latifolia (Griseb) Turcz) (CWR) has valuable biological and medicinal functions. To assess the advantages lost in modern cultivated rice after domestication, we compared the composition of bioactive compounds and the results of proteomic analysis with those of Indica rice (N22). We used routine methods to determine the protein, total dietary fiber, amino acid, mineral substance, plant secondary metabolites, and amino acid composition of CWR and N22. The protein and mineral contents of CWR were two times that of N22, and the levels of calcium, potassium, magnesium, chromium, iron, and zinc were significantly higher than those of N22 (P < .05). There was ~7.6 times more dietary fiber in CWR than in N22, but fewer carbohydrates (P < .05). Anthocyanins and chlorophyll were detected in CWR, but were absent from N22. Compared with N22, CWR had 53, 19, and 5.4 times higher (P < .05) levels of saponins, flavonoids, and plant sterols, respectively. The amino acid score of CWR was 66.6, which was significantly higher than N22. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) indicated that the main seed proteins of CWR were glutelins, including both acid and alkaline subunits, which were approximately twice those of N22. To investigate the differences in protein profiles between CWR and N22, we conducted two-dimensional electrophoresis (2-DE) analysis of the total proteins in the seeds of the two rice species. 2-DE gels revealed 19 differentially expressed proteins. Information obtained from peptide mass fingerprinting indicates that glutelin precursor caffeoyl coenzyme A (CoA) O-methyltransferase and putative bithoraxoid-like protein can provide good gene sources for improving rice quality.

Impact of high-temperature-water cooling damage on the mechanical properties of concrete

Zhai, Yue,Li, Yan,Li, Yubai,Wang, Siwei,Liu, Yi,Song, Ki-Il Elsevier 2019 Construction & building materials Vol.215 No.-

<P><B>Abstract</B></P> <P>A series of impact tests were conducted on split Hopkinson pressure bar equipment to study the influence of high-temperature-cooling damage on the mechanical properties of concrete. The experimental investigation showed the influence on the peak stress, peak strain, and fracture mode. The results indicate that the strain rate is directly related to the loading rate and heating temperature. The test results of natural cooling and water immersion cooling treatment were compared, which showed that the strength of water-cooled specimens is higher than that of naturally cooled specimens before the heating temperature reaches 400 °C and becomes much lower when the heating temperature is higher than 400 °C. Based on the experimental study, a dynamic non-linear elastic constitutive equation was established using a particle swarm optimization algorithm and an inversion analysis method. These results could provide theoretical references for the design of the ultimate strength of concrete materials for practical applications, such as fire and explosion prevention.</P> <P><B>Highlights</B></P> <P> <UL> <LI> High temperature-cooling damage on mechanical properties for concrete is tested. </LI> <LI> The strain rate is directly related to the loading rate and heating temperature. </LI> <LI> 400 °C can be considered as the threshold of high temperature-water cooling damage. </LI> <LI> Dynamic non-linear elastic constitutive equation is established. </LI> </UL> </P>

Orientation Control and Dielectric Properties of Sol-gel Deposited (Ba,Sr)TiO₃ Thin Films for Room-temperature Tunable Element Applications

Zhai, Jiwei,Chen, Haydn The Korean Ceramic Society 2003 한국세라믹학회지 Vol.40 No.4

The effects of the mole concentrations of precursor solution on the microstructure and dielectric properties of sol-gel deposited $Ba_{0.85}$S $r_{0.15}$Ti $O_3$(BST) thin films have been investigated. The films were of single perovskite phase with strong (100) preferred orientation when grown on LaNi0$_3$ buffered Pt/Ti/ $SiO_2$Si substrates using a diluted precursor solution. Variation of the precursor solution concentration resulted in a different microstructure and, in turn, affected the tunability of the sol-gel deposited films. It was observed that leakage currents increased asymmetrically for the negative and positive bias voltage with decreasing thickness. Overall results suggest that those BST films have acceptable properties f3r applications as room-temperature tunable elements.

You Know, I Know

Zhai Chongxiao 한국콘텐츠학회 2013 ICCC International Digital Design Invitation Exhib Vol.2013 No.-

Research on the Monitoring and Warning Mechanism about Operation of Funds in Universities of China

Zhai Huayun,Zheng Jun 한국경영교육학회 2011 한국경영교육학회 학술발표대회논문집 Vol.2011 No.12

Based on domestic and international early warning indicator system of funds security of universities, it is established the evaluation indicator system of funds security of universities in China from the micro level and the meso level of social, political and economic environments, and it is established the monitoring and warning mechanism about operation of funds in universities of China. Finally, it is analyzed the status of operation of funds in universities of China.

Model and Heuristics for the Heterogeneous Fixed Fleet Vehicle Routing Problem with Pick-Up and Delivering

Zhai Shuai,Chao Mao 한국유통과학회 2012 한국유통과학회 학술대회 논문집 Vol.2012 No.-

This paper discussed the heterogeneous fixed fleet vehicle routing problem with pick-up and delivery, which different type vehicles have different capacities, fixed costs and travel costs. A more practical mathematical model was established and because the NP-hard, we improved the traditional simulation annealing algorithm and test the new algorithm through a certain scale example. The results show that the new algorithm can obtain better solution, better stability. Through comparing the results of HFFVRP and HFFVRPPD, this paper illustrates the advantages of using HFFVRPPD for physical distribution enterprises in saving distribution vehicles, reducing logistics cost and raising economic benefits.

MPC-based Two-stage Rolling Power Dispatch Approach for Wind-integrated Power System

Zhai, Junyi,Zhou, Ming,Dong, Shengxiao,Li, Gengyin,Ren, Jianwen The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.2

Regarding the fact that wind power forecast accuracy is gradually improved as time is approaching, this paper proposes a two-stage rolling dispatch approach based on model predictive control (MPC), which contains an intra-day rolling optimal scheme and a real-time rolling base point tracing scheme. The scheduled output of the intra-day rolling scheme is set as the reference output, and the real-time rolling scheme is based on MPC which includes the leading rolling optimization and lagging feedback correction strategy. On the basis of the latest measured thermal unit output feedback, the closed-loop optimization is formed to correct the power deviation timely, making the unit output smoother, thus reducing the costs of power adjustment and promoting wind power accommodation. We adopt chance constraint to describe forecasts uncertainty. Then for reflecting the increasing prediction precision as well as the power dispatcher's rising expected satisfaction degree with reliable system operation, we set the confidence level of reserve constraints at different timescales as the incremental vector. The expectation of up/down reserve shortage is proposed to assess the adequacy of the upward/downward reserve. The studies executed on the modified IEEE RTS system demonstrate the effectiveness of the proposed approach.