Performance of Mg-Ti modified iron-based catalyst in NH3-SCR of NO at the presence of arsenic: Influence of oxygen and temperature

Xiaoyu Li,Juan Chen,Shouyan Chen,Chunmei Lu,Guangqian Luo,Hong Yao 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.101 No.-

Impact of arsenic on the performance of Mg-Ti modified iron-based catalyst during selective catalyticreduction of NOx with ammonia was studied. The results indicated that Mg and Ti modification not onlyimproved the catalytic activity at 100–350 C, but also exhibited remarkable anti-arsenic ability. Mg wasdominant in the excellent anti-arsenic performance, and this role was firstly recognized. The anti-arsenicmechanism of Mg-Ti modified iron-based catalyst was ascribed to two aspects. One side, Mg exhibitedwell reactivity with arsenic which competed with Fe for the adsorption of arsenic and protected activeiron sites from arsenic occupation. The other side, presence of Mg promoted the formation of MgFe2O4in view of the strong interactions between Mg and Fe, suppressing the interactions between arsenicand Fe. Instead, gaseous arsenic turned to bond with Mg-O sites. Consequently, surface acid sites andfunction Fe-OH/ Fe = O bonds were preserved for de-NOx. Moreover, increase of oxygen content and temperatureweakened the deactivation of Mg-Ti modified iron-based catalyst by arsenic. It was due to theoxidation of As2O3 with oxygen content increase and the strengthened reactivity of non-active iron siteswith arsenic and Mg with arsenic as temperature elevation, inhibiting the interactions between activeiron sites with arsenic.

Ozone infusiblization and curing mechanism of polysilazane ceramic precursor fibers

Li Xiaohong,Luo Xiaoyu,Li Jing,Li Jinxia,Yang Jiahao,Ahmad Zahoor,Bao Zhihao,Zhang Xiao,Chen Jianjun 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.5

An appropriate infusible method plays a vital role as one of the key processes of the fabrication of polymer-derived ceramic fibers. In this work, ozone curing, a novel room temperature controllable curing strategy was used to prepare SiCN ceramic fibers. Some circular pores were observed on the surface of the obtained SiCN ceramic fibers. The tensile strength of the fibers was also investigated. To reveal the ozone-curing mechanisms of the PSZ fibers and the formation process of the circular pores, the FT-IR, SEM, OM, XRD and TG were characterized. The results showed that the Si–H bonds and Si-CH3 groups in the PSZ molecule were oxidized gradually to form oxygen-containing groups such as Si–OH, Si–O-Si and C = O in the ozone curing process, which contributed to the curing and weight gain of the PSZ fibers. Moreover, a hydrolysis reaction between Si-NH-Si and H2O might further accelerate the curing of the PSZ fibers. An unexpected result of the hydrolysis reaction is the formation of some circular pores on the surface layer of the PSZ fibers. This strategy provides a method to design, adjust and control the microstructure and composition of silicon-based ceramic fibers, and the obtained SiCN fibers may be used as catalyst support, bacterial culture and other fields.

Mass Transfer Kinetics of Ultrasound-Assisted Steam Distillation for the Extraction of Cinnamon Oils

Shi Haixiang,Ling Xiaoyu,Luo Xuan,Su Tongming,Xie Xinling,Ji Hongbing,Qin Zuzeng 한국화학공학회 2024 Korean Journal of Chemical Engineering Vol.41 No.7

Ultrasound-assisted steam distillation (USD) increased the yield of cinnamon oils extracted from cinnamon leaves by fi tting a mass transfer kinetic model during the distillation process. A response surface optimization experiment was conducted to optimize the experimental conditions, which revealed that the order of factors was particle size, ultrasound power, ultrasound time, and pulse ratio. The optimal conditions were determined to be a 40 mesh particle size, 286 W ultrasound power, 31 min ultrasound time, and 7:3 pulse ratio, resulting in a 2.36% yield of cinnamon oils. The yield of cinnamon oils was 0.57% greater in USD than that of steam distillation (SD). The nonsteady-state diff usion model was the most suitable model for the distillation process. The washing coeffi cient b value of USD was 0.0210, indicating that cinnamon oils were enriched on the particle surface during the initial stages. The diff usion coeffi cient k of the USD was 0.1770, 40.36% higher than that of the SD, indicating a higher mass transfer effi ciency. The main components in cinnamon oils were cinnamaldehyde, coumarin, and 2-methoxycinnamaldehyde. Compared with those of SDs, USDs increased the diff usion coeffi cient k values of these components increased by 48.51%, 77.67%, and 82.43%, respectively. Ultrasound cavitation improved the mass transfer effi ciency of the distillation process, allowing components such as 2-methoxycinnamaldehyde to be more easily enriched in cinnamon oils than in other oils.

ssc-miR-185 targets cell division cycle 42 and promotes the proliferation of intestinal porcine epithelial cell

Wang, Wei,Wang, Pengfei,Xie, Kaihui,Luo, Ruirui,Gao, Xiaoli,Yan, Zunqiang,Huang, Xiaoyu,Yang, Qiaoli,Gun, Shuangbao Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.5

Objective: microRNAs (miRNAs) can play a role in a variety of physiological and pathological processes, and their role is achieved by regulating the expression of target genes. Our previous high-throughput sequencing found that ssc-miR-185 plays an important regulatory role in piglet diarrhea, but its specific target genes and functions in intestinal porcine epithelial cell (IPEC-J2) are still unclear. We intended to verify the target relationship between porcine miR-185 and cell division cycle 42 (CDC42) gene in IPEC-J2 and to explore the effect of miR-185 on the proliferation of IPEC-J2 cells. Methods: The TargetScan, miRDB, and miRanda software were used to predict the target genes of porcine miR-185, and CDC42 was selected as a candidate target gene. The CDC42-3' UTR-wild type (WT) and CDC42-3'UTR-mutant type (MUT) segments were successfully cloned into pmirGLO luciferase vector, and the luciferase activity was detected after co-transfection with miR-185 mimics and pmirGLO-CDC42-3'UTR. The expression level of CDC42 was analyzed using quantitative polymerase chain reaction and Western blot. The proliferation of IPEC-J2 was detected using cell counting kit-8 (CCK-8), methylthiazolyldiphenyl-tetrazolium bromide (MTT), and 5-ethynyl-2'-deoxyuridine (EdU) assays. Results: Double enzyme digestion and sequencing confirmed that CDC42-3'UTR-WT and CDC42-3'UTR-MUT were successfully cloned into pmirGLO luciferase reporter vector, and the luciferase activity was significantly reduced after co-transfection with miR-185 mimics and CDC42-3'UTR-WT. Further we found that the mRNA and protein expression level of CDC42 were down-regulated after transfection with miR-185 mimics, while the opposite trend was observed after transfection with miR-185 inhibitor (p<0.01). In addition, the CCK-8, MTT, and EdU results demonstrated that miR-185 promotes IPEC-J2 cells proliferation by targeting CDC42. Conclusion: These findings indicate that porcine miR-185 can directly target CDC42 and promote the proliferation of IPEC-J2 cells. However, the detailed regulatory mechanism of miR-185/CDC42 axis in piglets' resistance to diarrhea is yet to be elucidated in further investigation.

A Novel Non-contact Measurement Method for the Detection of Current Flowing Through Concealed Conductors

Yang Fan,Liu Kai,Zhu Liwei,Hu Jiayuan,Wang Xiaoyu,Shen Xiaoming,Luo Hanwu,Ammad Jadoon 한국자기학회 2017 Journal of Magnetics Vol.22 No.1

In order to detect the current flowing through concealed conductor, this paper proposes a new method based on derivative method. Firstly, this paper analyzes the main peak characteristic of the derivative function of magnetic field generated by a current-carrying conductor, and a relationship between the current flowing through the conductor and the main peak of the derivative function is obtained and applied to calculate the current. Then, the method is applied to detect the conductor current flowing through grounding grids of substations. Finally, the numerical experimental and field experiment verified the feasibility and accuracy of the method, and the computing results show that the method can effectively measure the conductor current of grounding grids with low error, and the error is within 5 %.

Apoptosis induced in vivo by new type gosling viral enteritis virus

Shun Chen,Anchun Cheng,Mingshu Wang,Dekang Zhu,Renyong Jia,Qihui Luo,Hengmin Cui,Yi Zhou,Yin Wang,Zhiwen Xu,Zhengli Chen,Xiaoyue Chen,Xiaoyu Wang 대한수의학회 2011 Journal of Veterinary Science Vol.12 No.4

In this study, apoptosis was induced by new type gosling viral enteritis virus (NGVEV) in experimentally infected goslings is reported in detail for the first time. After 3-day-old goslings were orally inoculated with a NGVEV-CN strain suspension, the time course of NGVEV effects on apoptotic morphological changes of the internal tissues was evaluated. These changes were observed by histological analysis with light microscopy and ultrastructural analysis with transmission electron microscopy. DNA fragmentation was assessed with a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and DNA ladder analysis. A series of characteristic apoptotic morphological changes including chromatin condensation and margination, cytoplasmic shrinkage, plasma membrane blebbing, and formation of apoptotic bodies were noted. Apoptosis was readily observed in the lymphoid and gastrointestinal organs, and sporadically occurred in other organs after 3 days post-infection (PI). The presence and quantity of TUNEL-positive cells increased with infection time until 9 days PI. DNA extracted from the NGVEV-infected gosling cells displayed characteristic 180~200 bp ladders. Apoptotic cells were ubiquitously distributed, especially among lymphocytes, macrophages, monocytes, and epithelial and intestinal cells. Necrosis was subsequently detected during the late NGVEV-infection phase, which was characterized by cell swelling, plasma membrane collapse, and rapidly lysis. Our results suggested that apoptosis may play an important role in the pathogenesis of NGVE disease.