Selective catalytic reduction of NOx with NH3 over titanium modified FexMgyOz catalysts: Performance and characterization

Liting Xu,Shengli Niu,Dong Wang,Chunmei Lu,Qi Zhang,Kang Zhang,Jing Li 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.63 No.-

A series of titanium modified FexMgyOz catalysts were prepared by coprecipitation method and impregnation-coprecipitation method with microwave assistant and their catalytic capability in selective catalytic reduction (SCR) was evaluated. Appropriate amount of either titanium or TiO2 could both improve the catalytic performance of FexMgyOz catalyst, especially above 350 °C. 7.5%Ti–FexMgyOz catalyst with wide temperature range of 225–400 °C could achieve the maximum NOx conversion of 100%, while FexMgyOz/TiO2(b) catalyst exhibited the best catalytic performance in the present of H2O and SO2. Characterization results exhibited that γ-Fe2O3 was the main active phase, TiO2 was mainly in the form of anatase TiO2 and both titanium and magnesium existed in amorphous phase. The crystalline grain could be refined with the addition of either titanium or TiO2, as well as the increase of BET surface area and pore volume. The acid sites, redox ability and the chemisorbed oxygen were the most important factors in SCR reaction. The introduction of titanium and TiO2 had the effect of increasing the strength of the acid sites, which could attribute to the improvement of catalytic performance over titanium modified FexMgyOz catalysts.

Iron-manganese-magnesium mixed oxides catalysts for selective catalytic reduction of NOx with NH3

Kang Zhang,Liting Xu,Shengli Niu,Chunmei Lu,Dong Wang,Qi Zhang,Jing Li 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.6

SCR activity at low temperature over iron oxide catalyst was prominently optimized by adding manganese and magnesium. Fe0.7Mn0.15Mg0.15Oz(n(Mn)/[n(Fe)+n(Mn)+n(Mg)])=0.15 and n(Mg)/[n(Fe)+n(Mn)+n(Mg)]=0.15) presented better performance in the low temperature SCR and NOx conversion of 90% could be achieved over 125 oC. Meanwhile, part of manganese and magnesium oxides were highly dispersed on the catalyst surface in an amorphous phase to react with iron oxide to form solid solution. Manganese and magnesium dopants could optimize the pore structure and distribution of γ-Fe2O3 to enhance the surface area and pore volume. Moreover, O2 participated in SCR reaction at a faster rate than NH3. In addition, the effect of SO2 was proved to be irreversible, whereas the inhibition of H2O could be rapidly removed after its removal.

Research on the Raman properties of NiFe/cicada wing composite SERS platform modified by silver nanoparticles

Zhang Anqi,Guo Liting,Li Na,Zhu Yanying,Jiao Tifeng,Wang Mingli 한국물리학회 2021 Current Applied Physics Vol.25 No.-

Composite structures have been widely concerned in the preparation of surface enhanced Raman scattering (SERS) substrates. In this paper, by solving the problem that the magnetic material was difficult to glow in magnetron sputtering, ferro-nickel (NiFe) alloy was deposited on the cicada wing (CW) and the NiFe/CW substrate was obtained. The results of sliver nanoparticles (Ag NPs) modified on the substrate were subsequently compared, and the SERS properties of the new Ag/NiFe/CW substrate were analyzed. Obviously, the intensity of SERS signals has been greatly improved after the modification of Ag NPs, and the substrate exhibits excellent reproducibility. The Ag NPs modified substrates were also applied to the detection of toxic crystal violet (CV) solution, which showed remarkable SERS activity. It has been proved that the strategy of modifying Ag NPs on the substrate to form a composite structure has great potential for improving the SERS performance of the substrate.

NH3-SCR performance and characterization over magnetic iron-magnesium mixed oxide catalysts

Liting Xu,Shengli Niu,Chunmei Lu,Dong Wang,Kang Zhang,Jing Li 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.5

A series of magnetic iron-magnesium mixed oxide catalysts (Fe1−xMgxOz) were synthesized via a novel coprecipitation method with microwave thermal treatment, and their activity in NH3-SCR was tested on a quartz fixedbed reactor. Physical and chemical properties of the catalysts were characterized by X-ray diffraction (XRD), N2- adsorption-desorption, scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). Fe0.8Mg0.2Oz with excellent N2 selectivity and resistance to SO2 and H2O was validated as the proper SCR catalyst, with the maximum NOx conversion of 99.1% fulfilled at 325 oC. Activity was strongly influenced by the γ-Fe2O3 crystalline phase, and magnesium existed in an amorphous phase and interacted with iron oxide intensively to form solid solution in favor of SCR. For Fe0.8Mg0.2Oz catalyst, optimum pore diameter distribution, appropriate surface area, pore volume and abundant lattice oxygen on the surface could be guaranteed, which is good for the diffusion process and enhances the activity.

Numerical study on the shock vector control performance in a de Laval nozzle with single or dual injection ports

Lite Zhang,Mengyu Su,Zilong Feng,Hao Guan,Haozhe Jin,Hong-Hui Shi 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.6

In this study, a comparison of five commonly used turbulence models was conducted in predictions of supersonic flows in a two-dimensional shock vector control nozzle. The result indicated that shear stress transport k-ω turbulence model performed best, and hence it was employed to carry out a parametric study on the shock wave vector control performance. The effects of slot interval distance, slot width, and injection angle on the deflection angle, thrust coefficient, and thrust efficiency were analyzed. All these performance parameters of a dual injection port nozzle can be better than those of a single injection port nozzle as long as the slot interval distance and width are appropriately selected. Under some investigated conditions, there exist an optimal slot interval distance and slot width both for the deflection angle and thrust efficiency, respectively.

Clinical report and genetic analysis of a novel variant in ZMIZ1 causing neurodevelopmental disorder with dysmorphic factors and distal skeletal anomalies in a Chinese family

He Liting,Wang Yao,Pan Jiahua,Guo Limin,Zhou Haoquan,Zhang Lan 한국유전학회 2024 Genes & Genomics Vol.46 No.4

Background Neurodevelopmental disorder with dysmorphic factors and distal skeletal anomalies (NEDDFSA) is a rare and phenotypically variable disorder. The zinc finger MIZ-type containing 1 gene (ZMIZ1) is a causative gene of NEDDFSA that encodes a protein inhibitor of the activated STAT-like family transcriptional regulator. Given the rarity of reported NEDDFSA cases, new phenotypes and genotypes of this disorder are still being discovered. Objective This study describes the phenotype characteristics of a Chinese NEDDFSA family caused by a novel ZMIZ1 variant. Methods We reviewed the clinical phenotype of a Chinese patient with NEDDFSA and performed whole-exome sequencing (WES) of the patient’s family. We simulated the potential biological harmfulness of the mutant protein. Plasmids were constructed and used for western blot and immunofluorescence assays to analyze protein expression levels. Results The patient was a 6-month-old male infant who exhibited dysmorphic facial features, neurodevelopmental abnormalities, congenital heart disease, and previously unreported genitourinary system anomalies. WES revealed a non-frameshift deletion variant in ZMIZ1 (NM_020338.4: c.858_875del, p.Val288_Ala293del), resulting in a structural alteration in the protein’s alanine-rich domain. Western blot and immunofluorescence assays indicated a significant decrease in the expression level of the mutant ZMIZ1 protein compared to the wild-type protein. Conclusion The clinical manifestations of this patient may be associated with the ZMIZ1 variant, and the structural alteration in the alanine-rich domain of the ZMIZ1 protein may contribute to a more complex disease phenotype. These results expand the genotype–phenotype correlation of ZMIZ1. Background Neurodevelopmental disorder with dysmorphic factors and distal skeletal anomalies (NEDDFSA) is a rare and phenotypically variable disorder. The zinc finger MIZ-type containing 1 gene (ZMIZ1) is a causative gene of NEDDFSA that encodes a protein inhibitor of the activated STAT-like family transcriptional regulator. Given the rarity of reported NEDDFSA cases, new phenotypes and genotypes of this disorder are still being discovered. Objective This study describes the phenotype characteristics of a Chinese NEDDFSA family caused by a novel ZMIZ1 variant. Methods We reviewed the clinical phenotype of a Chinese patient with NEDDFSA and performed whole-exome sequencing (WES) of the patient’s family. We simulated the potential biological harmfulness of the mutant protein. Plasmids were constructed and used for western blot and immunofluorescence assays to analyze protein expression levels. Results The patient was a 6-month-old male infant who exhibited dysmorphic facial features, neurodevelopmental abnormalities, congenital heart disease, and previously unreported genitourinary system anomalies. WES revealed a non-frameshift deletion variant in ZMIZ1 (NM_020338.4: c.858_875del, p.Val288_Ala293del), resulting in a structural alteration in the protein’s alanine-rich domain. Western blot and immunofluorescence assays indicated a significant decrease in the expression level of the mutant ZMIZ1 protein compared to the wild-type protein. Conclusion The clinical manifestations of this patient may be associated with the ZMIZ1 variant, and the structural alteration in the alanine-rich domain of the ZMIZ1 protein may contribute to a more complex disease phenotype. These results expand the genotype–phenotype correlation of ZMIZ1.

Transcriptome-based identification of the optimal reference genes as internal controls for quantitative RT-PCR in razor clam (Sinonovacula constricta)

Xuelin Zhao,Jianping Fu,Liting Jiang,Weiwei Zhang,Yina Shao,Chunhua Jin,Jinbo Xiong,Chenghua Li 한국유전학회 2018 Genes & Genomics Vol.40 No.6

Quantitative real-time PCR (qRT-PCR) is a standard method to measure gene expression in function exploring. Accurate and reproducible data of qRT-PCR requires appropriate reference genes, which are stably expressed under different experimental conditions. However, no housekeeping genes were validated as internal controls for qRT-PCR in Sinonovacula constricta. In this study, we classified the transcriptome data of two tissues for Vibrio infection and Cd2+ stress into ten clusters based on the gene expression patterns. Among them, cluster 5 had the most stable gene expression patterns regardless of tissues and treatments as the database for candidate reference genes. A total of 55 orthologs of classical housekeeping genes in the clam transcriptome were annotated. Combined the expression profiles and housekeeping genes in S. constricta, we chose eight candidate reference genes and validated their expression in Vibrio-infected samples and different tissues by qRT-PCR. Their expression stability was analyzed by three different algorithms geNorm, NormFinder and BestKeeper. Although the rank of the eight candidate reference genes is different in different treatments using different software, RS9 could be the best reference genes for normalization of qRT-PCR expression data in S. constricta under various treatments considering the above analysis. Meanwhile, the ranking of genes based on the CV values of transcriptomic data was similar to the validation results. This study provides for the first time a list of suitable reference genes for S. constricta and a valuable resource for further studies of clam immune defense systems.

Mechanical simulation for the bending process of the AMOLED panel pad

Wu Di,Jia Yongzhen,Liao Dunming,Zhang Bo,Liu Chen,Wang Ning,Peng Wenjing,Huang Liting 한국정보디스플레이학회 2023 Journal of information display Vol.24 No.2

Panel pad bending is a critical process to improve the screen-to-body ratio of an active-matrix organic light-emitting diode (AMOLED) panel. The failure analysis of the metal wirings is the key to ensure the reliability of signal transmission when the pad be bent to the back of the panel. In the present work, the sub-modeling technique combined with the periodic boundary condition was used to simulate the stress distribution of the bending area of the pad. The progressive failure of bent metal wirings was investigated by the extended finite element method. It is proved to be rational to prevent the wirings damage if the interlayer dielectric is replaced by an organic layer. In order to reduce stress of metal wirings, it is a measure to replace the original ultraviolet (UV) curable adhesive with a higher-modulus UV adhesive. The simulated results also show that rectangular perforations can avoid the stress concentration caused by the holes compared with circular perforations. For better stress distribution of metal wirings, it is necessary to increase the lengths of the rectangular holes and decrease the widths of that to a certain extent, which is helpful for restraining crack propagation by means of low-stress zones and holes.

Expression of Codon Optimized β₂-Adrenergic Receptor in Sf9 Insect Cells for Multianalyte Detection of β-Agonist Residues in Pork

( Yuan Liu ),( Jian Wang ),( Yang Liu ),( Liting Yang ),( Xuran Zhu ),( Wei Wang ),( Jiaxiao Zhang ),( Dong Wei ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.9

β₂-adrenergic receptor (β₂-AR) was expressed efficiently using Bac-to-Bac Baculovirus Expression System in Sf9 cells as a bio-recognition element for multianalyte screening of β-agonist residues in pork. Sf9 cells were selected as the expression system, and codon optimization of wild-type nucleic acid sequence and time-dependent screening of expression conditions were then carried out for enhancing expression level and biological activity. Under optimum conditions of multiplicity of infection (MOI) = 5 and 48 h post transfection, the protein yield was up to 1.23 mg/ml. After purification by chromatographic techniques, the purified recombinant protein was applied to develop a direct competitive enzyme-linked receptor assay (ELRA) and the efficiency and reliability of the assay was determined. The IC50 values of clenbuterol, salbutamol, and ractopamine were 28.36, 50.70, and 59.57 μg/l, and clenbuterol showed 47.61% and 55.94% cross-reactivities with ractopamine and salbutamol, respectively. The limit of detection (LOD) was 3.2 μg/l and the relevant recoveries in pork samples were in the range of 73.0-91.2%, 69.4-84.6%, and 63.7-80.2%, respectively. The results showed that it had better performance compared with other present nonradioactive receptor-based assays, indicating that the genetically modified β₂-AR would have great application potential in detection of β-agonist residues.

A Comparison of Eu-Doped -Fe2O3 Nanotubes and Nanowires for Acetone Sensing

Yali Cheng,Yifang Wang,Jinbao Zhang,Haiying Li,Li Liu,Yu Lina,Liting Du,Haojie Duan 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.11

Pure and Eu-doped (1.0, 3.0, 5.0 wt.%) α-Fe2O3 (PFO and EFO) nanotubes and nanowires have been successfully synthesized through the combination of electrospinning and calcination techniques. The structures, morphologies and chemical compositions of the as-obtained products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric and differential scanning calorimetry (TG-DSC) and energy dispersive spectrum (EDS), respectively. To demonstrate the superior gas sensing performance of the doped nanotubes, a contrastive gas sensing study between PFO (EFO) nanotubes and nanowires was performed. It turned out that Eu doping could magnify the impact of morphology on gas sensitivity. Specifically, at the optimum operating temperature of 240 ℃, the response value of PFO nanotubes to 100 ppm acetone is slightly higher than that of nanowires (3.59/2.20). EFO (3.0 wt.%) nanotubes have a response of 84.05, which is almost 2.7 times as high as that of nanowires (31.54). Moreover, they possess more rapid response/recovery time (11 s and 36 s, respectively) than nanowires (17 s and 40 s, respectively). The lowest detection limit for acetone is 0.1 ppm and its response is 2.15. In addition, both of EFO nanotubes and nanowires sensors have a good linearity (0.1–500 ppm) and favorable selectivity in acetone detection.