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Chemical looping oxidative propane dehydrogenation controlled by oxygen bulk diffusion over FeVO_(4)oxygen carrier pellets

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Chinese Journal of Chemical Engineering 2023年第1期53卷 409-420页

作者： Hongbo Song Wei wang Jiachen Sun xianhui wang Xianhua Zhang Sai Chen Chunlei Pei Zhi-Jian Zhao Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China Department of Chemistry National University of Singapore3 Science Drive 3117543Singapore

The oxygen distribution and evolution within the oxygen carrier exert significant influence on chemical looping processes.This paper describes the influence of oxygen bulk diffusion within FeVO4 oxygen carrier pellets on the chemical looping oxidative propane dehydrogenation(CL-ODH).During CL-ODH,the oxygen concentration at the pellet surface initially decreased and then maintained stable before the final decrease.At the stage with the stable surface oxygen concentration,the reaction showed a stable C3H6 formation rate and high C3H6 selectivity.Therefore,based on Fick’s second law,the oxygen distribution and evolution in the oxygen carrier at this stage were further analyzed.It was found that main reactions of selective oxidation and over-oxidation were controlled by the oxygen bulk diffusion.C3H8 conversion rate kept decreasing during this stage due to the decrease of the oxygen flux caused by the decline of oxygen gradient within the oxygen carrier,while C3H6 selectivity increased due to the decrease of overoxidation.In addition,reaction rates could increase with the propane partial pressure due to the increase of the oxygen gradient within the oxygen carrier until the bulk transfer reached its limit at higher propane partial pressure.This study provides fundamental insights for the diffusion-controlled chemical looping reactions.

关键词： Chemical looping Diffusion Reaction kinetics Oxygen carriers Oxidation

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Speech perception in noise:Masking and unmasking

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Journal of Otology 2021年第2期16卷 109-119页

作者： xianhui wang Li Xu Communication Sciences and Disorders Ohio UniversityAthensOH45701USA

Speech perception is essential for daily communication.Background noise or concurrent talkers,on the other hand,can make it challenging for listeners to track the target speech(i.e.,cocktail party problem).The present study reviews and compares existing findings on speech perception and unmasking in cocktail party listening environments in English and Mandarin Chinese.The review starts with an introduction section followed by related concepts of auditory masking.The next two sections review factors that release speech perception from masking in English and Mandarin Chinese,respectively.The last section presents an overall summary of the findings with comparisons between the two languages.Future research directions with respect to the difference in literature on the reviewed topic between the two languages are also discussed.

关键词： Speech perception Auditory masking Speech unmasking Cocktail party problems Mandarin Chinese

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Spherical hollow mesoporous silica supported phosphotungstic acid as a promising catalyst for α-arylstyrenes synthesis via Friedel-Crafts alkenylation

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Chinese Chemical Letters 2019年第3期30卷 729-734页

作者： xianhui wang Zhongkui Zhao State Key Laboratory of Fine Chemicals Department of Catalysis Chemistry and Engineering School of Chemical Engineering Dalian University of Technology

In this work, a spherical hollow mesoporous silica(SHMS) with high surface area(902 m^2/g) and large mesopore volume(1.31 cm^3/g) was prepared via a facile and scalable two-step soft-hard dual templateassisted sol-gel approach(OSDSG) by using glucose-derived carbon nano/micro particles(NMCP) as a hard template and cetyltrimethylammonium bromide(CTAB) as a soft template,respectively,in which the size-preselected carbon submicro-particle was used to replace ploymer sphere, and no extra precious additives like n-octadecyltrimethoxysilane(C18TMS). Supported phosphotungstic acid(PTA) catalysts on SHMS(PTA/SHMS) and on previously reported spherical mesoporous silica(PTA/SMS) with 25 wt% of PTA loading were prepared and employed as solid acid catalysts for diverse reactions. Transmission electron microscopy(TEM),N_2 adsorption-desorption, X-ray diffraction(XRD), and NH_3 temperatureprogrammed desorption(NH_3-TPD) techniques were employed to characterize the nature of carriers and supported PTA catalysts for revealing the structure-performance relationship. The developed PTA/SHMS catalyst demonstrates much higher catalytic activity than PTA/SMS for diverse reactions including alkenylation, esterification, alkylation, and benzylation, ascribed to the strengthened mass transfer and enlarged exposure degree of acidic sites to reactants those resulting from unique hollow and mesoporous morphology. Moreover, PTA/SHMS catalyst also exhibits outstanding catalytic performance for the diverse a-arylstyrenes via solid acid-mediated alkenylation. PTA/SHMS could be considered as a practical solid acid catalyst for diverse transformations.

关键词： Spherical hollow mesoporous silica Solid acid Mass transfer Alkenylation Heterogeneous catalysis

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Core transcriptional signatures of phase change in the migratory locust

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Protein & Cell 2019年第12期10卷 883-901页

作者： Pengcheng Yang Li Hou xianhui wang Le Kang Beijing Institutes of Life Science Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China

Phenotypic plasticity plays fundamental roles in successful adaptation of animals in response to environmental variations.Here,to reveal the transcriptome reprogramming in locust phase change,a typical phenotypic plasticity,we conducted a comprehensive analysis of multiple phase-related transcriptomic datasets of the migratory locust.We defined PhaseCore genes according to their contribution to phase differentiation by the adjustment for confounding principal components analysis algorithm(AC-PCA).Compared with other genes,PhaseCore genes predicted phase status with over 87.5%accuracy and displayed more unique gene attributes including the faster evolution rate,higher CpG content and higher specific expression level.Then,we identified 20 transcription factors(TFs)named PhaseCoreTF genes that are associated with the regulation of PhaseCore genes.Finally,we experimentally verified the regulatory roles of three representative TFs(Hr4,Hr46,and grh)in phase change by RNAi.Our findings revealed that core transcriptional signatures are involved in the global regulation of locust phase changes,suggesting a potential common mechanism underlying phenotypic plasticity in insects.The expression and network data are accessible in an online resource called LocustMine(http://***:8080/locustmine).

关键词： phenotypic plasticity transcriptional regulatory network RNA interference

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Relationship between powder characteristic and internal oxidation of Al in Cu-Al pre-alloyed powders

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Acta Metallurgica Sinica(English Letters) 2009年第1期22卷 71-80页

作者： Shuhua LIANG xianhui wang Liang FANG Zhikang FAN Department of Materials Science and Engineering Xi＇an University of Technology Xi＇an 710048 China State Key Laboratory for Mechanical Behavior of Materials Xi＇an Jiaotong University Xi＇an 710049 China

Since Cu-Al powder characteristics have important effects on the preparation of Cu/Al2O3 composite, the apparent activation energy of Al internal oxidation reaction in Cu-Al pre-alloyed powders with different characteristics was calculated in the present investigation. The microstructure and properties of the synthesized Cu/Al2O3 were studied. The results show that high-energy milling can obviously promote internal oxidation of Al in Cu-Al powders in the same solid solubility. At the same milling conditions and internal oxidation parameters, the solid solution of Al in Cu either in low or high amount will result in the poor microstructure and properties of the Cu/Al2O3 composite. Subsequently, when high-energy milling and internal oxidation are synchronously used to prepare the Cu/Al2O3 composite, there should be an appropriate solubility and milling effect for the pre-alloyed powders.

关键词： Powder characteristic Internal oxidation Cu/Al2O3 composite material Solid solution Reaction rate

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某纯电驱动重载车辆能耗预测模型

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兵工学报 2024年第4期45卷 1229-1236页

作者：王尔烈王帅皮大伟王洪亮王显会谢伯元南京理工大学机械工程学院江苏南京210094 江苏省商用车智能底盘工程研究中心江苏南京210094 先进越野系统技术全国重点实验室北京100072

高精度能耗预测模型是准确预测车辆续驶里程的重要前提。针对载荷大幅度变化且非结构化道路运行的纯电驱动重载车辆,建立其组合能耗模型,该模型由能耗计算基本模型与长短时记忆(Long Short-Term Memory,LSTM)神经网络差值修正两部分组... 详细信息

高精度能耗预测模型是准确预测车辆续驶里程的重要前提。针对载荷大幅度变化且非结构化道路运行的纯电驱动重载车辆,建立其组合能耗模型,该模型由能耗计算基本模型与长短时记忆(Long Short-Term Memory,LSTM)神经网络差值修正两部分组成。基于能量流动过程驱动电机和变速器效率建模,结合汽车行驶动力学建立能耗计算基本模型;采用LSTM神经网络来修正基本模型能耗预测结果与车辆典型工况功率测试值的差值,有效提高了大幅变载荷且低信噪比坡度环境下的车辆能耗预测精度,因此组合能耗模型具有参数简单和模型拟合不需解释能耗规律的优点。经试验测试分析,与VT-Micro能耗模型和径向基(Radial Basis Function,RBF)神经网络能耗模型相比,所提组合能耗模型的功率预测平均误差率分别降低了17.76%和3.35%,能够实现纯电驱动重载车辆复杂工况下能耗的准确实时预测。

关键词：纯电驱动重载车辆组合能耗模型长短时记忆神经网络行驶动力学复杂工况

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Combination of steam-enhanced extraction and electrical resistance heating for efficient remediation of perchloroethylene-contaminated soil:Coupling merits and energy consumption

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Frontiers of Environmental Science & Engineering 2022年第11期16卷 249-260页

作者： Rui Yue Zhikang Chen Liujun Liu Lipu Yin Yicheng Qiu xianhui wang Zhicheng wang Xuhui Mao School of Resource and Environmental Sciences Wuhan UniversityWuhan 430079China China State Science Dingshi Environmental Engineering Company Beijing 100020China

In situ thermal desorption(ISTD)technology effectively remediates soil contaminated by dense nonaqueous phase liquids(DNAPLs).However,more efforts are required to minimize the energy consumption of ISTD technology.This study developed a laboratory-scale experimental device to explore the coupling merits of two traditional desorption technologies:steam-enhanced extraction(SEE)and electrical resistance heating(ERH).The results showed that injecting high-density steam(>1 g/min)into loam or clay with relatively high moisture content(>13.3%)could fracture the soil matrix and lead to the occurrence of the preferential flow of steam.For ERH alone,the electrical resistance and soil moisture loss were critical factors influencing heating power.When ERH and SEE were combined,preheating soil by ERH could increase soil permeability,effectively alleviating the problem of preferential flow of SEE.Meanwhile,steam injection heated the soil and provided moisture for maintaining soil electrical conductivity,thereby ensuring power stability in the ERH process.Compared with ERH alone(8 V/cm)and SEE alone(1 g/min steam),the energy consumption of combined method in remediating perchloroethylene-contaminated soil was reduced by 39.3%and 52.9%,respectively.These findings indicate that the combined method is more favorable than ERH or SEE alone for remediating DNAPL-contaminated subsurfaces when considering ISTD technology.

关键词： Steam-enhanced extraction Electrical resistance heating Dense nonaqueous phase liquid Soil remediation Energy consumption

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Correction to:Core transcriptional signatures of phase change in the migratory locust

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Protein & Cell 2020年第9期11卷 696-697页

作者： Pengcheng Yang Li Hou xianhui wang Le Kang Bejjing Institutes of Life Science Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China

In the original publication the photo of the gregarious adult locust in Fig.1A is incorrect.The correct photo of adult migratory locust is provided in this correction.OPEN ACCESS This article is licensed under a Creative Commons Attribution 4.0 International License,which permits use,sharing,adaptation,distribution and reproduction in any medium or format,as long as you give appropriate credit to the original author(s)and the source,provide a link to the Creative Commons licence,and indicate if changes were made.The images or other third party material in this article are included in the article's Creative Commons licence,unless indicated otherwise in a credit line to the material.If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use,you will need to obtain permission directly from the copyright holder.

关键词： ACCESS OPEN signature

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Composition and emission dynamics of migratory locust volatiles in response to changes in developmental stages and population density

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Insect Science 2017年第1期24卷 60-72页

作者： Jianing Wei Wenbo Shao xianhui wang Jin Ge Xiangyong Chen Dan Yu Le Kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China

Chemical communication plays an important role in density-dependent phase change in locusts. However, the volatile components and emission patterns of the migratory locust, Locusta migratoria, are largely unknown. In this study, we identified the chemical compositions and emission dynamics of locust volatiles from the body and feces and associated them with developmental stages, sexes and phase changes. The migratory locust shares a number of volatile components with the desert locust （Schistocerca gregaria）, but the emission dynamics of the two locust species are significantly different. The body odors of the gregarious nymphs in the migratory locust consisted of phenylacetonitrile （PAN）, benzaldehyde, guaiacol, phenol, aliphatic acids and 2,3-butanediol, and PAN was the dominant volatile. Volatiles from the fecal pellets of the nymphs primarily consist of guaiacol and phenol. Principal component analysis （PCA） showed significant differences in the volatile profiles between gregarious and solitary locusts. PAN and 4-vinylanisole concentrations were significantly higher in gregarious individuals than in solitary locusts. Gregarious mature males released significantly higher amounts of PAN and 4-vinylanisole during adulthood than mature females and immature adults of both sexes. Furthermore, PAN and 4-vinylanisole were completely lost in gregarious nymphs during the solitarization process, but were obtained by solitary nymphs during gregarization. The amounts of benzaldehyde, guaiacol and phenol only unidirectionally decreased from solitary to crowded treatment. Aliphatic aldehydes （C7 to C10）, which were previously reported as locust volatiles, are now identified as environmental contaminants. Therefore, our results illustrate the precise odor profiles of migratory locusts during developmental stages, sexes and phase change. However, the function and role of PAN and other aromatic compounds during phase transition need further investigation.

关键词： GC-MS/MS Locusta migratoria phase change phenylacetonitrile volatile chemicals

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Independent variations in genome-wide expression, alternative splicing, and DNA methylation in brain tissues among castes of the buff-tailed bumblebee, Bombus terrestris

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Journal of Genetics and Genomics 2021年第8期48卷 681-694页

作者： Dan Zhu Jin Ge Siyuan Guo Li Hou Rangjun Shi Xian Zhou Xin Nie xianhui wang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100080China CAS Centre for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijing 100049China

Caste differentiation in social hymenopterans is an intriguing example of phenotypic plasticity. However, the co-ordination among gene regulatory factors to mediate caste differentiation remains inconclusive. In this study, we determined the role of gene regulation and related epigenetic processes in pre-imaginal caste differentiation in the primitively eusocial bumblebee Bombus terrestris. By combining RNA-Seq data from Illumina and Pac Bio and accurately quantifying methylation at whole-genomic base pair resolution, we found that queens, workers, and drones mainly differentiate in gene expression but not in alternative splicing and DNA methylation. Gynes are the most distinct with the lowest global level of whole-genomic methylation and with the largest number of caste-specific transcripts and alternative splicing events. By contrast, workers exhibit few uniquely expressed or alternatively spliced genes. Moreover, several genes involved in hormone and neurotransmitter metabolism are related to caste differentiation, whereas several neuropeptides are linked with sex differentiation. Despite little genome-wide association among differential gene expression, splicing, and differential DNA methylation, the overlapped gene ontology(GO) terms point to nutrition-related activity. Therefore, variations in gene regulation correlate with the behavioral differences among castes and highlight the specialization of toolkit genes in bumblebee gynes at the beginning of the adult stage.

关键词： Social insects Caste determination PacBio Epigenetics Methylome RNA-seq WGBS-seq

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