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Modification of acidity in HZSM-5 zeolite for methane-methanol co-reaction

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第2期22卷 106-115页

作者： bing-jie zhou Zhi-xiang XI Yue YU Bin-bo JIANG Jing-dai WANG Zu-wei LIAO Zheng-liang HUANG Yong-rong YANG Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology Department of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Chemical Engineering Zhejiang UniversityHangzhou 310027China

A co-reaction of methane with methanol over zeolite catalysts has emerged as a new approach to the long-standing challenge of methane ***,the effect of catalyst acid properties on the co-reaction has been rarely *** this study,a series of HZSM-5 zeolites with comparable diffusion abilities and various acidities were synthesized directly through steaming with 100%water vapor at 693 *** co-reaction of methane and methanol was subsequently ***?nsted acidity at 0.262 mmol/g was detected to reach the maximum methane conversion of 5.42%at 673 K,which was also the odd point in the relationship between acid concentration and C4 hydrogen transfer ***,the influence of methanol feed was investigated over parent and steamed ZSM-5 catalyst,with results showing that excessive acid sites or methanol molecules reduce methane *** is proposed that acid sites adsorbed with methanol molecules construct the methane activation ***,a proper design of zeolite acidity should be achieved to obtain higher methane conversion in the co-reaction process.

关键词： Methane conversion Methanol Co-reaction Acidity HZSM-5

Surface-confined persistent luminescence with amplified FRET efficiency for cell-cell communication monitoring

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Science China Chemistry 2025年

作者： Ziyun Miao Wenjing Dai Yubin Jin bing Qi Jiayi Chen Lingling Qiu Yurong Wei jie Wang The Key Lab of Health Chemistry&Molecular Diagnosis of Suzhou College of ChemistryChemical Engineering&Materials ScienceSoochow University

Microbial communication monitoring is vital for understanding the mechanisms beneath gut microbiota equilibrium, infections,and biomanufacturing. Herein, we reported monitoring bacterial communication by surface-confined persistent ***, we constructed core-shell structured Zn1.4Ga1.2Ge0.4O4@Zn1.4Ga1.2Ge0.4O4:Cr（ZGGO@ZGGO:Cr） persistent luminescence nanoparticles（PLNPs） with amplified FRET efficiency for the detection of azoreductase（AzoR） that participates in bacterial communication. ZGGO@ZGGO:Cr nanoparticles were functionalized with an azo black hole quencher（ZGGO@ZGGO:Cr-BHQ-3）. Due to the proximity of surface-confined persistent luminescence with the surface-bound BHQ-3,ZGGO@ZGGO:Cr-BHQ-3 exhibited a FRET efficiency up to 1.6 times that of traditional ZGGO:Cr-BHQ-3. Further, the specific catalytic reduction of azo bonds in BHQ-3 by bacterial extracellular AzoR recovers the persistent luminescence of ZGGO@ZGGO:Cr. ZGGO@ZGGO:Cr-BHQ-3 displayed superior sensitivity and speed in detecting extracellular AzoR over ZGGO:Cr-BHQ-3, attributed to its surface-confined persistent luminescence. We found that the peak secretion of AzoR occurs during the exponential growth period of bacteria including S. aureus and E. coli based on the persistent luminescence recovery rate of ZGGO@ZGGO:Cr-BHQ-3. Furthermore, ZGGO@ZGGO:Cr-BHQ-3 was used to probe the communication between different bacterial species. R. palustris is a kind of lycopene-production bacteria. We found that the cohabitation of R. palustris and S. putrefaciens boosted both AzoR secretion and lycopene production. Moreover, the secretion and activity of AzoR positively correlated with lycopene production, suggesting that AzoR may participate in the communication between R. palustris and S. putrefaciens to promote lycopene production. This study offers a robust method to enhance PLNP-based biosensing sensitivity and provides a promising strategy for microbial communication monitoring.

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醋粉喷雾干燥工艺的优化

食品工业科技 2017年第21期38卷 203-208,215页

作者：朱崇阳夏蓉武靓靓林冰洁周炜杰陶汇源程永强植物源功能食品北京市重点实验室中国农业大学食品科学与营养工程学院北京100083 江苏恒顺生物工程有限公司江苏镇江212000 北京联合大学应用文理学院北京100083

为了优化醋粉的喷雾干燥工艺,以市售镇江香醋为原料,制得醋粉。以进口温度、物料浓度、麦芽糊精添加量及进料速率为影响参数,采用单因素实验和正交实验相结合的方法优化喷雾干燥工艺。结果表明:在进口温度160℃、物料浓度25%、麦芽糊精... 详细信息

为了优化醋粉的喷雾干燥工艺,以市售镇江香醋为原料,制得醋粉。以进口温度、物料浓度、麦芽糊精添加量及进料速率为影响参数,采用单因素实验和正交实验相结合的方法优化喷雾干燥工艺。结果表明:在进口温度160℃、物料浓度25%、麦芽糊精添加量30%、进料速率400 m L·h^(-1)的条件下获得的醋粉品质较佳,该条件下醋粉的含水率为8.39%,集粉率为66.58%,DPPH自由基半清除率浓度(IC_(50))为0.773 mg·m L^(-1),有机酸含量为18.44%,总色差值为21.94。本研究结果为优质醋粉的研制提供了依据。

关键词：醋粉喷雾干燥正交实验优化

一起220kV线路重合闸充电灯不亮缺陷分析

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电气开关 2017年第4期55卷 86-88,92页

作者：叶东华胡炳杰周晨晖国家电网公司漳州供电公司福建漳州363000

本文描述了一起220 kV线路保护充电灯不亮的缺陷,对保护装置重合闸闭锁回路进行分析,判断出测控中间继电器处于复归状态,导致操作箱中间继电器闭锁重合闸,是本次缺陷的主要原因。结合缺陷处理过程,提出了缺陷处理的建议,进一步提高缺陷... 详细信息

本文描述了一起220 kV线路保护充电灯不亮的缺陷,对保护装置重合闸闭锁回路进行分析,判断出测控中间继电器处于复归状态,导致操作箱中间继电器闭锁重合闸,是本次缺陷的主要原因。结合缺陷处理过程,提出了缺陷处理的建议,进一步提高缺陷处理的成功率,保障电网安全稳定运行。

关键词：线路保护重合闸二次回路

Enzyme-instructed self-assembly of peptides containing phosphoserine to form supramolecular hydrogels as potential soft biomaterials

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Frontiers of Chemical Science and Engineering 2017年第4期11卷 509-515页

作者： zhou, jie Du, Xuewen Wang, Jiaqing Yamagata, Natsuko Xu, bing Brandeis Univ Dept Chem Waltham MA 02453 USA

Enzyme-instructed self-assembly （EISA） offers a facile approach to explore the supramolecular assemblies of small molecules in cellular milieu for a variety of biomedical applications. One of the commonly used enzymes is phosphatase, but the study of the substrates of phosphatases mainly focuses on the phos- photyrosine containing peptides. In this work, we examine the EISA of phosphoserine containing small peptides for the first time by designing and synthesizing a series of precursors containing only phosphoserine or both phos- phoserine and phosphotyrosine. Conjugating a phospho- serine to the C-terminal of a well-established self- assembling peptide backbone, （naphthalene-2-1y）-acetyl- diphenylalanine （NapFF）, affords a novel hydrogelation precursor for EISA. The incorporation ofphosphotyrosine, another substrate of phosphatase, into the resulting precursor, provides one more enzymatic trigger on a single molecule, and meanwhile increases the precursors＇ propensity to aggregate after being fully dephosphorylated. Exchanging the positions of phosphorylated serine and tyrosine in the peptide backbone provides insights on how the specific molecular structures influence self-assembling behaviors of small peptides and the subsequent cellular responses. Moreover, the utilization of D-amino acids largely enhances the biostability of the peptides, thus providing a unique soft material for potential biomedical applications.

关键词： enzyme-instructed self-assembly phosphoser-ine phosphatase supramolecular hydrogel

Analysis of wave propagation in micro/nanobeam-like structures: A size-dependent model

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Acta Mechanica Sinica 2012年第6期28卷 1659-1667页

作者： bing-Lei Wang Jun-Feng Zhao Shen-jie zhou Xi Chen Department of Engineering Mechanics Shandong University School of Mechanical Engineering Shandong University Department of Earth and Environmental Engineering Columbia University International Center for Applied Mechanics SV Lab School of Aerospace Xi'an Jiaotong University

By incorporating the strain gradient elasticity into the classical Bernoulli-Euler beam and Timoshenko beam models, the size-dependent characteristics of wave propaga- tion in micro/nanobeams is studied. The formulations of dis- persion relation are explicitly derived for both strain gradi- ent beam models, and presented for different material length scale parameters （MLSPs）. For both phenomenological size- dependent beam models, the angular frequency, phase veloc- ity and group velocity increase with increasing wave num- ber. However, the velocity ratios approach different values for different beam models, indicating an interesting behavior of the asymptotic velocity ratio. The present theory is also compared with the nonlocal continuum beam models.

关键词： Strain gradient elasticity theory ~ Bernoulli-Euler beam theory. Timoshenko beam theory Wave propa-gation

Ko⁃LLaMA:基于LLaMA的朝鲜语大语言模型

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外语学刊 2025年第1期 1-8页

作者：庞杰闫晓东赵小兵中央民族大学北京100081 国家语言资源监测与研究民族语言中心北京100081 民族语言智能与安全治理教育部重点实验室北京100081

在本文中,我们通过扩展LLaMA现有的词表,增加额外的20,000个朝鲜语Token,从而提高其对朝鲜语的编码和语义理解的能力;并且进一步使用朝鲜语数据进行继续预训练,使用朝鲜语指令微调数据集对模型进行SFT(Supervised Fine⁃Tuning),并分析... 详细信息

在本文中,我们通过扩展LLaMA现有的词表,增加额外的20,000个朝鲜语Token,从而提高其对朝鲜语的编码和语义理解的能力;并且进一步使用朝鲜语数据进行继续预训练,使用朝鲜语指令微调数据集对模型进行SFT(Supervised Fine⁃Tuning),并分析不同数据量对指令精调效果的影响,经过继续预训练和指令微调后的模型显著提高了理解和遵循朝鲜语指令的能力。实验结果表明,新提出的模型Ko⁃LLaMA显著提高了原版LLaMA在理解和生成朝鲜语内容方面的能力。此外,在朝鲜语文本分类数据集YNAT上对Ko⁃LLaMA与擅长少数民族语言的CINO模型及CINO的多种模型组合以及原版LLaMA和GPT⁃3.5进行了效果对比。结果表明,Ko⁃LLaMA的朝鲜语文本分类能力远超CINO和CINO的组合模型以及LLaMA和GPT⁃3.5等未经过朝鲜语语料进行词表扩充和继续预训练的大语言模型。

关键词：朝鲜语大语言模型词表扩充继续预训练指令微调

Supramolecular Nanofibers/Hydrogels of the Conjugates of Nucleobase,Saccharide,and Amino Acids

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Chinese Journal of Chemistry 2014年第4期32卷 313-318页

作者： Dongdong Wu Xuewen Du Junfeng Shi jie zhou bing Xu Department of Chemistry Brandeis University415 South St.WalthamMA 02454USA

Three new hydrogelators based on the conjugates of three naturally occurring biological building blocks:nu-cleobase,saccharide,and amino acids,were *** synthesized via a facile solid phase peptide synthesis route,the hydrogelators self-assemble in water to afford supramolecular nanofibers and *** electron microscopy,oscillation rheometry,and circular dichroism reveal that the hydrogels consist of largely he-lix-based nanofibers of the widths of 5-12 nm and exhibit storage moduli up to 1 *** hydrogelators also exhibit excellent *** work illustrates a new platform for constructing molecular soft materials for nanobiotechnology.

关键词： hydrogelator nucleoside peptide nanofiber

Stereoselective Syntheses and Biological Properties of (E)-α-(Methoxyimino)-2-[1-(aryloxy)methyl]-benzeneacetates

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Chemical Research in Chinese Universities 2006年第1期22卷 45-50页

作者： LI Yan LIU jie zhou Ye-bing ZHANG Hong-quan CHEN Zu-xin LIU Zhao-jie Key Laboratory of Pesticide ＆ Chemical Biology of the Education Ministry of China Central China Normal University Wuhan 430079 P. R. China Faculty of Chemistry and Materials Science Hubei University Wuhan 430062 P. R. China

（E） -α- （ Methoxyimi no ） -2 - [ 1-（aryloxy） methyl ]-benzeneacetates, the analogues of Kresoxim-methyl, were ste- rcoselectively synthesized with the coupling reaction of 2-methylphenyldiazonium chloride and methyl 2-hydroxyiminoacetate in the presence of CuSO4/Na2SO3 as a key step, and it was first found that the coupling reaction could give the key intermediate material（ E）- and（Z）-methyl 2-（hydroxyimino）-2-o-tolylacetate with a molar ratio of 14： 1. The （E）-configurations of all these compounds were assigned on the basis of their 2D-NOESY spectra of ^1H NMR. The preliminary bioassays indicate that most of the compounds show an activity against a wide variety of fungi.

关键词： Kresoxim-methyl Fungicide Stereoselective coupling reaction Strobilufin