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PGUS1 hybrid nanoflower through protein-inorganic self-assembly, and its application in glycyrrhetinic acid3-O-mono-β-D-glucuronide preparation

Tian Jiang, Yuhui Hou, Tengjiang Zhang, Xudong Feng, Chun Li

《化学科学与工程前沿（英文）》 2019年 第13卷 第3期   页码 554-562 doi: 10.1007/s11705-019-1834-z

摘要： Glycyrrhetinic acid 3- -mono- -D-glucuronide (GAMG), an important pharmaceutical intermediate and functional sweetener, has broad applications in the food and medical industries. A green and cost-effective method for its preparation is highly desired. Using site-directed mutagenesis, we previously obtained a variant of -glucuronidase from Li-3 (PGUS1), which can specifically transform glycyrrhizin (GL) into GAMG. In this study, a facile method was established to prepare a CaHPO -PGUS1 hybrid nanoflower for enzyme immobilization, based on protein-inorganic hybrid self-assembly. Under optimal conditions, 1.2 mg of a CaHPO -PGUS1 hybrid nanoflower precipitate with 71.2% immobilization efficiency, 35.60 mg∙g loading capacity, and 118% relative activity was obtained. Confocal laser scanning microscope and scanning electron microscope results showed that the enzyme was encapsulated in the CaHPO -PGUS1 hybrid nanoflower. Moreover, the thermostability of the CaHPO -PGUS1 hybrid nanoflower at 55°C was improved, and its half-life increased by 1.3 folds. Additionally, the CaHPO -PGUS1 hybrid nanoflower was used for the preparation of GAMG through GL hydrolysis, with the conversion rate of 92% in 8 h, and after eight consecutive runs, it had 60% of its original activity.

关键词： β-glucuronidase     enzyme-inorganic hybrid nanoflower     biotransformation     glycyrrhizin     glycyrrtinic acid 3-O-mono-β-D-glucuronide    

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Development of lunar regolith-based composite for - 3D printing via high-pressure extrusion system

《机械工程前沿（英文）》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0745-8

摘要： To fully utilize the in-situ resources on the moon to facilitate the establishment of a lunar habitat is significant to realize the long-term residence of mankind on the moon and the deep space exploration in the future. Thus, intensive research works have been conducted to develop types of 3D printing approach to adapt to the extreme environment and utilize the lunar regolith for in-situ construction. However, the in-situ 3D printing using raw lunar regolith consumes extremely high energy and time. In this work, we proposed a cost-effective melting extrusion system for lunar regolith-based composite printing, and engineering thermoplastic powders are employed as a bonding agent for lunar regolith composite. The high-performance nylon and lunar regolith are uniformly pre-mixed in powder form with different weight fractions. The high-pressure extrusion system is helpful to enhance the interface affinity of polymer binders with lunar regolith as well as maximize the loading ratio of in-situ resources of lunar regolith. Mechanical properties such as tensile strength, elastic modulus, and Poisson’s ratio of the printed specimens were evaluated systematically. Especially, the impact performance was emphasized to improve the resistance of the meteorite impact on the moon. The maximum tensile strength and impact toughness reach 36.2 MPa and 5.15 kJ/m2, respectively. High-pressure melt extrusion for lunar regolith composite can increase the effective loading fraction up to 80 wt.% and relatively easily adapt to extreme conditions for in-situ manufacturing.

关键词： in-situ resource utilization     melt extrusion molding     lunar regolith-based composites     mechanical properties     additive manufacturing    

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H2 对Pt-Ba-Ce /γ-Al2O3 催化剂NO<i>xi> 存储和还原机理的影响研究 Article

王攀, 裔静, 孙川, 罗鹏, 雷利利

《工程（英文）》 2019年 第5卷 第3期   页码 568-575 doi: 10.1016/j.eng.2019.02.005

摘要：

本研究采用浸渍法制备了Pt-Ba-Ce/γ-Al2O3催化剂，利用实验评价了H2 对NSR（NOx storage and reduction）催化剂存储和还原机理的影响，并采用综合表征技术研究了Pt-Ba-Ce /γ-Al2O3x、CeO2 和BaCO3 峰很好地分散在γ-Al2O3 上，X 射线光电子能谱（XPS）检测到Ce3+ 和Ce4+ 之间的差异，Ce3+ 和Ce4+ 促进了活性氧在催化剂上的迁移。

关键词： Pt–Ba–Ce/γ-Al2O3 催化剂，物理化学性质，NO<i>xi>存储和还原，NO<i>xi> 排放    

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Functional characterization of caffeic acid

Fengyan WU, Zhenying WU, Aiguo YANG, Shanshan JIANG, Zeng-Yu WANG, Chunxiang FU

《农业科学与工程前沿（英文）》 2018年 第5卷 第1期   页码 98-107 doi: 10.15302/J-FASE-2017198

摘要： Caffeic acid -methyltransferase (COMT) is a crucial enzyme that mainly methylates phenylpropanoid -hydroxyl of C in the biosynthesis of syringyl lignin in angiosperms. A putative , named as , was isolated from switchgrass ( ), a C warm-season dual-purpose forage and bioenergy crop. Our results showed that recombinant PvCOMT1 enzyme protein catalyzed the methylation of 5-OH coniferyl alcohol, 5-OH coniferaldehyde (CAld5H) and 5-OH ferulic acid. Further studies indicate that CAld5H can dominate COMT-mediated reactions by inhibiting the methylation of the other substrates. Transgenic switchgrass plants generated by an RNAi approach were further employed to study the function of in internode lignification. A dramatic decrease in syringyl lignin units coupled with an obvious incorporation in 5-OH guaiacyl lignin units were observed in the COMT-RNAi transgenic plants. However, the constitutive suppression of COMT in switchgrass plants altered neither the pattern of lignin deposition along the stem nor the anatomical structure of internodes. Consistent with the biochemical characterization of PvCOMT1, a significant decrease in sinapaldehyde was found in the COMT-RNAi transgenic switchgrass plants, suggesting that CAld5H could be the optimal intermediate in the biosynthesis syringyl lignin.

关键词： biofuel crop     caffeic acid O-methyltransferase     forage     lignin     Panicum virgatum     switchgrass     transgenic plant    

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CFD evaluation of pressure drop across a 3-D filter housing for industrial gas turbine plants

Fidelis I. ABAM,Samuel O. EFFIOM,Olayinka S. OHUNAKIN

《能源前沿（英文）》 2016年 第10卷 第2期   页码 192-202 doi: 10.1007/s11708-016-0406-x

摘要： This paper investigated the flow distribution and total pressure drop across a designed 3-D filter housing integrated with a 3-stage filtration system using computational fluid dynamics (CFD). The filter housing model was proposed for a heavy-duty industrial gas turbine plant operating at an average ambient temperature of 20°C.The pressure drops across the classes of filters were 652.8 Pa, 2692.2 Pa, 887.8 Pa, 776.2 Pa and 2304.2 Pa for I-GB, GB-GA, GA-FA, FA-HA, and HA-O, respectively. The results obtained indicated an acceptable total pressure drop of 7.2% for the entire filter housing before filter clean-up. Although the CFD simulation result shows that small outlet flow velocity and transonic flows exist at the outlet of the filter housing, the designed filter housing was proved compatible with the studied GT, for inlet flow conditions between 600≤ ≤610 kg/s and 60≤ ≤70 m/s for the air flow rate and velocity, respectively. Furthermore, the designed filter housing could be adopted for the studied GT and locations of Usan and Maiduguri in Nigeria, and other locations with similar environmental conditions.

关键词： computational fluid dynamics (CFD)     pressure drop     flow distribution     filter housing     gas turbine    

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Genomic and metabolomic analysis of with enhanced poly--glutamic acid production through atmospheric

《化学科学与工程前沿（英文）》 2022年 第16卷 第12期   页码 1751-1760 doi: 10.1007/s11705-022-2211-x

摘要： Poly-γ-glutamic acid is an extracellular polymeric substance with various applications owing to its valuable properties of biodegradability, flocculating activity, water solubility, and nontoxicity. However, the ability of natural strains to produce poly-γ-glutamic acid is low. Atmospheric and room temperature plasma was applied in this study to conduct mutation breeding of Bacillus licheniformis CGMCC 2876, and a mutant strain M32 with an 11% increase in poly-γ-glutamic acid was obtained. Genome resequencing analysis identified 7 nonsynonymous mutations of ppsC encoding lipopeptide synthetase associated with poly-γ-glutamic acid metabolic pathways. From molecular docking, more binding sites and higher binding energy were speculated between the mutated plipastatin synthase subunit C and glutamate, which might contribute to the higher poly-γ-glutamic acid production. Moreover, the metabolic mechanism analysis revealed that the upregulated amino acids of M32 provided substrates for glutamate and promoted the conversion between L- and D-glutamate acids. In addition, the glycolytic pathway is enhanced, leading to a better capacity for using glucose. The maximum poly-γ-glutamic acid yield of 14.08 g·L–1 was finally reached with 30 g·L–1 glutamate.

关键词： ARTP mutagenesis     Bacillus licheniformis     poly-γ-glutamic acid     metabolomics    

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通过<i> B i>位Ta置换对<i> AB i> O4型EuNbO4的热学和力学性质进行优化 Article

陈琳, 冯晶

《工程（英文）》 2020年 第6卷 第2期   页码 177-184 doi: 10.1016/j.eng.2019.12.006

摘要：

铁弹性的ABO4型RETaO4陶瓷和RENbO4陶瓷（RE表示稀土）是具有潜在应用价值的热障涂层（TBC）材料，

关键词： 热障涂层，稀土铌酸盐，置换，热导率，热膨胀系数，杨氏模量    

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On the monolayer dispersion behavior of Co3O4 on HZSM-5 support: designing applicable

《化学科学与工程前沿（英文）》 2023年 第17卷 第11期   页码 1741-1754 doi: 10.1007/s11705-023-2332-x

摘要： Based on monolayer dispersion theory, Co3O4/ZSM-5 catalysts with different loadings have been prepared for selective catalytic reduction of nitrogen oxides by ammonia. Co3O4 can spontaneously disperse on HZSM-5 support with a monolayer dispersion threshold of 0.061 mmol 100 m–2, equaling to a weight percentage around 4.5%. It has been revealed that the quantities of surface active oxygen (O2–) and acid sites are crucial for the reaction, which can adsorb and activate NOx and NH3 reactants effectively. Below the monolayer dispersion threshold, Co3O4 is finely dispersed as sub-monolayers or monolayers and in an amorphous state, which is favorable to generate the two kinds of active sites, hence promoting the performance of ammonia selective catalytic reduction of nitrogen oxide. However, the formation of crystalline Co3O4 above the capacity is harmful to the reaction performance. 4% Co3O4/ZSM-5, the catalyst close to the monolayer dispersion capacity, possesses the most abundant active O2– species and acidic sites, thereby demonstrating the best reaction performance in all the samples. It is proposed the optimal Co3O4/ZSM-5 catalyst can be prepared by loading the capacity amount of Co3O4 onto HZSM-5 support.

关键词： Co3O4/ZSM-5     NOx-SCR by NH3     monolayer dispersion threshold effect     surface acid sites     surface active O2– anions    

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Novel variants in LAMA3 and COL7A1 and recurrent variant in KRT5 underlying epidermolysis bullosa in

《医学前沿（英文）》 2022年 第16卷 第5期   页码 808-814 doi: 10.1007/s11684-021-0878-x

摘要： Epidermolysis bullosa (EB) is a group of clinically and genetically heterogeneous diseases characterized by trauma-induced mucocutaneous fragility and blister formation. Here, we investigated five Chinese families with EB, and eight variants including a novel nonsense variant (c.47G>A, p.W16*) in LAMA3, a known recurrent variant (c.74C>T, p.P25L) in KRT5, 2 novel (c.2531T>A, p.V844E; c.6811_6814del, p.R2271fs) and 4 known (c.6187C>T, p.R2063W; c.7097G>A, p.G2366D; c.8569G>T, p.E2857*; c.3625_3635del, p.S1209fs) variants in COL7A1 were detected. Notably, this study identified a nonsense variant in LAMA3 that causes EB within the Chinese population and revealed that this variant resulted in a reduction in LAMA3 mRNA and protein expression levels by nonsense-mediated mRNA decay. Our study expands the mutation spectra of Chinese patients with EB.

关键词： epidermolysis bullosa     LAMA3     COL7A1     KRT5     Chinese families    

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Development of an H reduction and moderate oxidation method for 3,5-dimethylpyridine hydrogenation in

《化学科学与工程前沿（英文）》 2022年 第16卷 第12期   页码 1807-1817 doi: 10.1007/s11705-022-2243-2

摘要： The Ru/C catalyst prepared by impregnation method was used for hydrogenation of 3,5-dimethylpyridine in a trickle bed reactor. Under the same reduction conditions (300 °C in H2), the catalytic activity of the non-in-situ reduced Ru/C-n catalyst was higher than that of the in-situ reduced Ru/C-y catalyst. Therefore, an in-situ H2 reduction and moderate oxidation method was developed to increase the catalyst activity. Moreover, the influence of oxidation temperature on the developed method was investigated. The catalysts were characterized by Brunauer–Emmett–Teller method, hydrogen temperature programmed reduction H2-TPR, hydrogen temperature-programmed dispersion (H2-TPD), X-ray diffraction, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, O2 chemisorption and oxygen temperature-programmed dispersion (O2-TPD) analyses. The results showed that there existed an optimal Ru/RuOx ratio for the catalyst, and the highest 3,5-dimethylpyridine conversion was obtained for the Ru/C-i1 catalyst prepared by in-situ H2 reduction and moderate oxidation (oxidized at 100 °C). Excessive oxidation (200 °C) resulted in a significant decrease in the Ru/RuOx ratio of the in-situ H2 reduction and moderate oxidized Ru/C-i2 catalyst, the interaction between RuOx species and the support changed, and the hard-to-reduce RuOx species was formed, leading to a significant decrease in catalyst activity. The developed in-situ H2 reduction and moderate oxidation method eliminated the step of the non-in-situ reduction of catalyst outside the trickle bed reactor.

关键词： Ru/C catalyst     in-situ H2 reduction and moderate oxidation     in-situ reduction     non-in-situ reduction     hydrogenation of 3     5-dimethylpyridine    

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<i>NES1i>/<i>KLK10i> and <i>hNISi> gene therapy enhanced iodine-131 internal radiation in PC3 proliferation

Jiajia Hu, Wenbin Shen, Qian Qu, Xiaochun Fei, Ying Miao, Xinyun Huang, Jiajun Liu, Yingli Wu, Biao Li

《医学前沿（英文）》 2019年 第13卷 第6期   页码 646-657 doi: 10.1007/s11684-018-0643-y

摘要： gene is thought to be a tumor-suppressor gene. Our previous study found that overexpression of gene in PC3 cell line could slow down the tumor proliferation rate, associated with a mild decrease in expression. The decrease could increase the sensitivity of radiotherapy to tumors. Thus, we supposed to have an “enhanced firepower” effect by combining overexpressed gene therapy and I radiation therapy uptake by overexpressed hNIS protein. We found a weak endogenous expression of hNIS protein in PC3 cells and demonstrated that the low expression of hNIS protein in PC3 cells might be the reason for the low iodine uptake. By overexpressing in PC3, the radioactive iodine uptake ability was significantly increased. Results of and tumor proliferation experiments and F-fluorothymidine ( F-FLT) micro-positron emission tomography/computed tomography (micro-PET/CT) imaging showed that the combined gene therapy and I radiation therapy mediated by overexpressed hNIS protein had the best tumor proliferative inhibition effect. Immunohistochemistry showed an obvious decrease of expression and the lowest expression. These data suggest that via inhibition of expression, overexpressed might enhance the effect of radiation therapy of I uptake in overexpressed PC3 cells.

关键词： androgen-independent prostate cancer     normal epithelial cell-specific 1/kallikrein 10     sodium/iodide symporter     radiation therapy     proliferation    

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Magnetic Co-doped 1D/2D structured -FeO/MoS effectively activated peroxymonosulfate for efficient abatement

《环境科学与工程前沿（英文）》 2023年 第18卷 第3期 doi: 10.1007/s11783-024-1797-2

摘要：

● Magnetic Co- γ -Fe2O3/MoS2 were prepared via facile hydrothermal methods.

关键词： Magnetic Co-γ-Fe2O3/MoS2     Hydrothermal method     Bisphenol A     Degradation pathways     Toxicity analysis    

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Effects of Pd doping on N

Mingxin Dong, Jun Wang, Jinxin Zhu, Jianqiang Wang, Wulin Wang, Meiqing Shen

《环境科学与工程前沿（英文）》 2017年 第11卷 第6期 doi: 10.1007/s11783-017-0976-9

摘要： N O is a powerful greenhouse gas and plays an important role in destructing the ozone layer. This present work investigated the effects of Pd doping on N O formation over Pt/BaO/Al O catalyst. Three types of catalysts, Pt/BaO/Al O , Pt/Pd mechanical mixing catalyst (Pt/BaO/Al O +Pd/Al O ) and Pt-Pd co-impregnation catalyst (Pt-Pd/BaO/Al O ) were prepared by incipient wetness impregnation method. These catalysts were first evaluated in NSR activity tests using H /CO as reductants and then carefully characterized by BET, CO chemisorption, CO-DRIFTs and H -TPR techniques. In addition, temperature programmed reactions of NO with H /CO were conducted to obtain further information about N O formation mechanism. Compared with Pt/BaO/Al O , (Pt/BaO/Al O +Pd/Al O ) produced less N O and more NH during NO storage and reduction process, while an opposite trend was found over (Pt-Pd/BaO/Al O +Al O ). Temperature programmed reactions of NO with H /CO results showed that Pd/Al O component in (Pt/BaO/Al O +Pd/Al O ) played an important role in NO reduction to NH , and the formed NH could reduce NO to N leading to a decrease in N O formation. Most of N O formed over (Pt-Pd/BaO/Al O +Al O ) was originated from Pd/BaO/Al O component. H -TPR results indicated Pd-Ba interaction resulted in more difficult-to-reduce PdO species over Pd/BaO/Al O , which inhibits the NO dissociation and thus drives the selectivity to N O in NO reduction.

关键词： NOx storage reduction     Pt/BaO/Al2O3     Pd doping     N2O formation     Optimization    

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Fatigue crack growth simulations of 3-D linear elastic cracks under thermal load by XFEM

Himanshu PATHAK,Akhilendra SINGH,I.V. SINGH,S. K. YADAV

《结构与土木工程前沿（英文）》 2015年 第9卷 第4期   页码 359-382 doi: 10.1007/s11709-015-0304-z

摘要： This paper deals with the fatigue crack growth simulations of three-dimensional linear elastic cracks by XFEM under cyclic thermal load. Both temperature and displacement approximations are extrinsically enriched by Heaviside and crack front enrichment functions. Crack growth is modelled by successive linear extensions, and the end points of these linear extensions are joined by cubic spline segments to obtain a modified crack front. Different crack geometries such as planer, non-planer and arbitrary spline shape cracks are simulated under thermal shock, adiabatic and isothermal loads to reveal the sturdiness and versatility of the XFEM approach.

关键词： 3-D cracks     fatigue life     Paris law     thermal load     XFEM    

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Enhanced production of

Shen Huang,Xudong Feng,Chun Li

《化学科学与工程前沿（英文）》 2015年 第9卷 第4期   页码 501-510 doi: 10.1007/s11705-015-1544-0

摘要： -Glucuronidase from Li-3 (PGUS) can efficiently hydrolyze glycyrrhizin into the more valuable glycyrrhetic acid monoglucuronide. However, a low productivity of PGUS and the lack of an effective separation strategy have significantly limited its industrial applications. Therefore, the production of PGUS has been improved by optimizing both the fermentation and purification strategies. A two-stage fermentation strategy was developed where PGUS was first grown with glucose and then PGUS was produced in the presence of glycyrrhizin as an inducer. By using this strategy, the biomass was increased 1.5 times and the PGUS activity increased 5.4 times compared to that when glycyrrhizin was used as the sole carbon source. The amount of PGUS produced was increased another 16.6% when the fermentation was expanded to a 15-L fermenter. An effective protocol was also established to purify the PGUS using a sequential combination of hydrophobic, strong anion-exchange and gel filtration chromatography. This protocol had a recovery yield of 6% and gave PGUS that was 39 times purer than the crude PGUS. The purified PGUS had a specific activity of 350 U·mg .

关键词： β-glucuronidase     glycyrrhetic acid monoglucuronide     cell disruption     purification     chromatography    

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标题 作者 时间 类型 操作

PGUS1 hybrid nanoflower through protein-inorganic self-assembly, and its application in glycyrrhetinic acid3-O-mono-β-D-glucuronide preparation

Tian Jiang, Yuhui Hou, Tengjiang Zhang, Xudong Feng, Chun Li

期刊论文

Development of lunar regolith-based composite for - 3D printing via high-pressure extrusion system

期刊论文

H2 对Pt-Ba-Ce /γ-Al2O3 催化剂NO<i>xi> 存储和还原机理的影响研究

王攀, 裔静, 孙川, 罗鹏, 雷利利

期刊论文

Functional characterization of caffeic acid

Fengyan WU, Zhenying WU, Aiguo YANG, Shanshan JIANG, Zeng-Yu WANG, Chunxiang FU

期刊论文

CFD evaluation of pressure drop across a 3-D filter housing for industrial gas turbine plants

Fidelis I. ABAM,Samuel O. EFFIOM,Olayinka S. OHUNAKIN

期刊论文

Genomic and metabolomic analysis of with enhanced poly--glutamic acid production through atmospheric

期刊论文

通过<i> B i>位Ta置换对<i> AB i> O4型EuNbO4的热学和力学性质进行优化

陈琳, 冯晶

期刊论文

On the monolayer dispersion behavior of Co3O4 on HZSM-5 support: designing applicable

期刊论文

Novel variants in LAMA3 and COL7A1 and recurrent variant in KRT5 underlying epidermolysis bullosa in

期刊论文

Development of an H reduction and moderate oxidation method for 3,5-dimethylpyridine hydrogenation in

期刊论文

<i>NES1i>/<i>KLK10i> and <i>hNISi> gene therapy enhanced iodine-131 internal radiation in PC3 proliferation

Jiajia Hu, Wenbin Shen, Qian Qu, Xiaochun Fei, Ying Miao, Xinyun Huang, Jiajun Liu, Yingli Wu, Biao Li

期刊论文

Magnetic Co-doped 1D/2D structured -FeO/MoS effectively activated peroxymonosulfate for efficient abatement

期刊论文

Effects of Pd doping on N

Mingxin Dong, Jun Wang, Jinxin Zhu, Jianqiang Wang, Wulin Wang, Meiqing Shen

期刊论文

Fatigue crack growth simulations of 3-D linear elastic cracks under thermal load by XFEM

Himanshu PATHAK,Akhilendra SINGH,I.V. SINGH,S. K. YADAV

期刊论文

Enhanced production of

Shen Huang,Xudong Feng,Chun Li

期刊论文