Effects of regeneration conditions on sulfated CuSSZ-13 catalyst for NH3-SCR

Meiqing Shen,Zhixin Wang,Xinhua Li,Jiaming Wang,Jianqiang Wang,Chen Wang,Jun Wang 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.8

To understand the role of regeneration conditions on sulfur-poisoned Cu/SSZ-13 catalysts for NH3-SCR, the physicochemical characterizations and NOx conversions were investigated. The sulfur-poisoned Cu/SSZ-13 catalysts were treated at different conditions as a function of temperature and duration. TGA results revealed that regeneration at 500 oC only removed parts of sulfur spices and at 700 oC can completely remove all sulfur spices. The physical structural characterizations results illustrate that regeneration below 700 oC has no significant impact on CHA structure for Cu/SSZ-13 catalysts, while dealumination occurs on poisoned Cu/SSZ-13 when regeneration temperature is higher than 700 oC. EPR and H2-TPR results show that the sulfate decomposition and Cu migration reactions involved during regeneration and, as a result, the content of Cu2+ gradually increased as the extent of regeneration increased. The kinetics tests support that NOx conversion recovery is related to the content of Cu2+ increase during regeneration. Our study reveals that the optimum regeneration temperature is 700 oC, because severe dealumination at 750 oC inhibited Cu2+ amount increase.

A Novel Bacterial Cellulose Aerogel Modified with PGMA via ARGET ATRP Method for Catalase Immobilization

Xinhua Liu,Hongliang Zheng,Yong Li,Liping Wang,Cuie Wang 한국섬유공학회 2019 Fibers and polymers Vol.20 No.3

Formation of Poly(Glycidyl Methacrylate) (PGMA) films on bacterial cellulose (BC) supports (aerogels) wasachieved via activators regenerated by electron transfer for atom transfer radical polymerization (ARGET ATRP). Epoxygroups on PGMA were used for covalent coupling with catalase. Immobilized catalases on BC@PGMA were characterized by Fourier transform infrared spectroscopy (FTIR) and Typical scanning electron microscopy (SEM). The immobilized catalase amount reached a high value of 116 mg/g. Furthermore, the thermal, pH and storage stabilities of the immobilized catalase were improved significantly. After 10 use cycles, the BC@PGMA-catalase still retained approximately 63.5 % of the initial activity. This work demonstrates the potential of hierarchical nanomaterials for improving enzyme performance, leveraging the benefits of both nano- and macroscale supports. These results demonstrate that the BC@PGMA-catalase has high stability and good reusability, suggesting that the BC aerogel modified with PGMA may find applications in biotechnology and as biocatalyst.

Memantine Improves Cognitive Function and Alters Hippocampal and Cortical Proteome in Triple Transgenic Mouse Model of Alzheimer’s Disease

Xinhua Zhou,Liang Wang,Wei Xiao,Zhiyang Su,Chengyou Zheng,Zaijun Zhang,Yu Qiang Wang,Benhong Xu,Xifei Yang,Maggie Pui Man Hoi 한국뇌신경과학회 2019 Experimental Neurobiology Vol.28 No.3

Memantine is a non-competitive N-methyl-D-aspartate receptor (NMDAR) antagonist clinically approved for moderate-to-severe Alzheimer’s disease (AD) to improve cognitive functions. There is no report about the proteomic alterations induced by memantine in AD mouse model yet. In this study, we investigated the protein profiles in the hippocampus and the cerebral cortex of AD-related transgenic mouse model (3×Tg-AD) treated with memantine. Mice (8-month) were treated with memantine (5 mg/kg/bid) for 4 months followed by behavioral and molecular evaluation. Using step-down passive avoidance (SDA) test, novel object recognition (NOR) test and Morris water maze (MWM) test, it was observed that memantine significantly improved learning and memory retention in 3xTg-AD mice. By using quantitative proteomic analysis, 3301 and 3140 proteins in the hippocampus and the cerebral cortex respectively were identified to be associated with AD abnormalities. In the hippocampus, memantine significantly altered the expression levels of 233 proteins, among which PCNT, ATAXIN2, TNIK, and NOL3 were up-regulated, and FLNA, MARK 2 and BRAF were down-regulated. In the cerebral cortex, memantine significantly altered the expression levels of 342 proteins, among which PCNT, PMPCB, CRK, and MBP were up-regulated, and DNM2, BRAF, TAGLN 2 and FRY1 were down-regulated. Further analysis with bioinformatics showed that memantine modulated biological pathways associated with cytoskeleton and ErbB signaling in the hippocampus, and modulated biological pathways associated with axon guidance, ribosome, cytoskeleton, calcium and MAPK signaling in the cerebral cortex. Our data indicate that memantine induces higher levels of proteomic alterations in the cerebral cortex than in the hippocampus, suggesting memantine affects various brain regions in different manners. Our study provides a novel view on the complexity of protein responses induced by memantine in the brain of AD.

Expanding Application of Immobilized Candida Antarctica Lipase B: A Green Enzyme Catalyst for Knoevenagel Condensation Reaction

Cuie Wang,Ning Wang,Xinhua Liu,Peng Wan,Xinwei He,Yongjia Shang 한국섬유공학회 2018 Fibers and polymers Vol.19 No.8

We propose a green synthesis of benzopyran compound based on immobilized lipase. Firstly, by using a combined electrospun membrane and biocompatible chitosan, we show that the chitosan-functionalized electrospun PMA-co-PAA fibrous membrane can provide effective anchoring sites for immobilization of the Candida antarctica lipase B (CALB), and a maximum loading amount of CALB (152 mg/g) can be achieved. Then, the resulting membrane displays enhanced stability in catalyzing Knoevenagel condensation reaction of salicylaldehyde with active methylene compound in mixed aqueousorganic media. The catalytic activity and stability of the CALB on chitosan-modified fiber is better than its non-immobilized counterpart. Furthermore, this immobilize CALB catalyst still retained about 45 % of the initial activity after 5 cycles, which potentially had implications for the design of “green” enzyme catalyst for sustainable organic synthesis.

Amygdalin inhibits HSC-T6 cell proliferation and fibrosis through the regulation of TGF-β/CTGF

Huanhuan Luo,Liang Li,Jianbang Tang,Fengxue Zhang,Fang Zhao,Da Sun,Fengling Zheng,Xinhua Wang,Xinhua Wang 대한독성 유전단백체 학회 2016 Molecular & cellular toxicology Vol.12 No.3

Amygdalin is one of the nitrilosides that was widely used to treat cancer, inhibit liver fibrosis. In the present study, the aim was to determine the antifibrotic potential of amygdalin and examine its mechanisms of action in vitro. Firstly, we found amygdalin significantly inhibited HSC-T6 cells proliferation. Both mRNA and protein of transforming growth factor-β (TGF-β) were decreased in HSC-T6 cells during amygdalin treatment. Secondly, to investigate functional role of TGF-β, both TGF-β over-expression vector and siRNA against TGF-β were transfected into HSC-T6 cells respectively. The results showed that over-expression of TGF-β promoted proliferation of HSC-T6 cells, whereas TGF-β knockdown inhibited cell viability. Moreover, our data even indicated that TGF-β could promote cell proliferation independent of amygdalin treatment. Finally, we found amygdalin could inhibit expression of the classical fibrotic factor αSMA, which suggested an antifibrotic effect of amygdalin. While the TGF-β antagonized anti-fibrotic effect of amygdalin. To assess the mechanisms, we examined expression of CTGF in cultured HSC-T6 cells. Our results showed that CTGF was down-regulated in HSCT6 cell treated by amygdalin, but was up-regulated when exogenous TGF-β introduced. As CTGF was one of the downstream factors in the TGF-β pathway. These might suggest that amygdalin inhibited HSC-T6 cells proliferation and fibrosis via TGF-β/CTGF pathway.

Regioselective Nitration of Inactive 4,4-Dibromobiphenyl with Nitrogen Dioxide and Molecular Oxygen over Zeolites: An Efficient Preparation of 4,4'-Dibromo-2-nitrobiphenyl

Wang, Wei,Peng, Xinhua,Chen, Nan Korean Chemical Society 2014 대한화학회지 Vol.58 No.1

In the presence of zeolites, 4,4'-dibromobiphenyl could be region-selectively nitrated by the action of nitrogen dioxide and molecular oxygen. The ratio of 4,4'-dibromo-2-nitrobiphenyl to 4,4'-dibromo-3-nitrobiphenyl could reach 14 in a high yield of 90%. Zeolites could be easily regenerated by heating and reused four times to give the results similar to those obtained with fresh catalyst. Compared with the classic nitration method, no nitric acid and sulfuric acid were used, which suggested that the method was an environmentally economic process.

Study on the removal of chromium(III) from leather waste by a two-step method

Li Wang,Jun Liu,Yang Jin,Ming Chen,JianHong Luo,Xinhua Zhu,Yuqiang Zhang 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.79 No.-

The removal of chromium(III) from leather solid waste was carried out by two steps: the leaching stepand the ion exchange step. Orthogonal method was applied to the leaching process with H2SO4 asleaching agent and the leaching rate was nearly 100%. The adsorption and desorption of Cr3+ with 732#cation exchange resins were investigated in the ion exchange process. The effects of the resin types,temperature, rotating speed, liquid-solid ratio, initial Cr3+ concentration and time were investigated andthe optimum conditions were as follows: 732#, 333 K, 120 r/min, 20 ml/g, 280 ppm and 5 h. The removalefficiency of Cr3+ from leather hydrolysate was over 95% under optimized conditions. The desorptionefficiency of Cr3+ from loaded resins was almost 99% by three times cross-flow with Na2SO4 solution. There-adsorption of Cr3+ could achieve 95% by regenerated resins. The adsorption isotherms, kinetics andthermodynamics of Cr3+ onto 732# resins were investigated. The adsorption process appeared to followLangmuir isotherm model and the pseudo-second-order kinetic model. 4H0 = 33,816.03 kJ/mol and4S0 = 141.35 J/(mol K) were calculated. The two-step method was proved to be a sustainable andeconomic method for separating chromium from leather waste.

A SVPWM algorithm based on four‑switch three‑phase inverter for PMSM under the imbalance of bus capacitor voltage

Shoucheng Huang,Xinhua Guo,Rongkun Wang,Yunhui Mei 전력전자학회 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.12

In a four-switch three-phase inverter-powered permanent magnet synchronous motor system, the capacitor voltage fluctuates due to the unequal capacitance and the charging and discharging of the bus capacitor. As such, the accuracy of motor vector control becomes significantly affected and even causes the shutdown of the motor drive system. Therefore, this study proposed a space vector PWM (SVPWM) algorithm that considers capacitor voltage imbalance. In the case of voltage basic vector offset, this algorithm first constructs a new orthogonal voltage basic vector and takes the offset modulation range as the constraint condition to synthesize a new target voltage vector. Compared with the traditional SVPWM algorithm, the proposed SVPWM algorithm controls the capacitor voltage fluctuation range in a reasonable range, simplifies the calculation, improves the three-phase stator current asymmetry, and reduces the current harmonic content. Simulation and experimental results demonstrate the effectiveness and feasibility of the proposed SVPWM algorithm.

Lack of Association Between the Matrix Metalloproteinase-2 -1306C>T Polymorphism and Breast Cancer Susceptibility: a Meta-analysis

Yang, Lu,Li, Ning,Wang, Siyu,Kong, Yanan,Tang, Hailin,Xie, Xinhua,Xie, Xiaoming Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.12

Background: Since inconsistent results have been reported regarding the relation between the matrix metalloproteinase-2 (MMP-2) -1306C>T polymorphism and susceptibility for breast cancer, we performed a meta-analysis to investigate the issue. Materials and Methods: An internet search of PubMed and EMBASE was performed to identify eligible studies. Pooled odds ratios (ORs) with their corresponding confidence intervals (CIs) were calculated to evaluate any association between MMP-2 -1306C>T polymorphism and breast cancer susceptibility. Results: Nine case-control studies were included in the meta-analysis, involving 9,858 cases and 10,871 controls. Overall, there was no evidence of any association between the MMP-2 -1306C>T polymorphism and breast cancer susceptibility in different genetic models (T-allele vs C-allele: OR=0.95, 95%CI, 0.82-1.10, p=0.49; TT vs CC: OR=1.03, 95%CI, 0.90-1.19, p=0.66; TT+TC vs CC: OR=0.93, 95%CI, 0.78-1.10, p=0.38; TT vs TC+CC: OR=1.02, 95%CI, 0.89-1.17, p=0.77). In the subgroup analysis by ethnicity, CC was associated with a significant increase in breast susceptibility among Latin-Americans in the dominant model (OR=0.61, 95%CI, 0.40-0.93, p=0.02), but the association disappeared in other models. No significant association was observed among Europeans, East Asians and others in different genetic models. In the subgroup analysis by their source of controls, no significant association between MMP-2 -1306C>T polymorphism and breast cancer susceptibility was noted among population-based studies and hospital-based studies in different genetic models. Conclusions: The results of this meta-analysis suggest that MMP-2 -1306C>T polymorphism is not associated with breast cancer susceptibility, although the association among Latin-Americans in the dominant model was significant.

Expression characterization and transcription regulation analysis of porcine Yip1 domain family member 3 gene

Ni, Dongjiao,Huang, Xiang,Wang, Zhibo,Deng, Lin,Zeng, Li,Zhang, Yiwei,Lu, Dongdong,Zou, Xinhua Asian Australasian Association of Animal Productio 2020 Animal Bioscience Vol.33 No.3

Objective: The Yip1 domain family (YIPF) proteins were proposed to function in endoplasmic reticulum (ER) to Golgi transport and maintenance of the morphology of the Golgi, which were homologues of yeast Yip1p and Yif1p. YIPF3, the member 3 of YIPF family was a homolog of Yif1p. The aim of present study was to investigate the expression and regulation mechanism of porcine YIPF3. Methods: Quantitative realtime polymerase chain reaction (qPCR) was used to analyze porcine YIPF3 mRNA expression pattern in different tissues and pig kidney epithelial (PK15) cells stimulated by polyinosine-polycytidylic acid (poly [I:C]). Site-directed mutations combined with dual luciferase reporter assays and electrophoretic mobility shift assay (EMSA) were employed to reveal transcription regulation mechanism of porcine YIPF3. Results: Results showed that the mRNA of porcine YIPF3 (pYIPF3) was widely expressed with the highest levels in lymph and lung followed by spleen and liver, while weak in heart and skeletal muscle. Subcellular localization results indicated that it expressed in Golgi apparatus and plasma membranes. Upon stimulation with poly (I:C), the level of this gene was dramatically up-regulated in a time- and concentration-dependent manner. pYIPF3 core promoter region harbored three cis-acting elements which were bound by ETS proto-oncogene 2 (ETS2), zinc finger and BTB domain containing 4 (ZBTB4), and zinc finger and BTB domain containing 14 (ZBTB14), respectively. In which, ETS2 and ZBTB4 both promoted pYIPF3 transcription activity while ZBTB14 inhibited it, and these three transcription factors all played important regulation roles in tumorigenesis and apoptosis. Conclusion: The pYIPF3 mRNA expression was regulated by ETS2, ZBTB4, and ZBTB14, and its higher expression in immune organs might contribute to enhancing ER to Golgi transport of proteins, thus adapting to the immune response.