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Clay-Supported Molybdenum-Based Catalysts for Higher Alcohol Synthesis from Syngas

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Chinese Journal of Chemical Physics 2015年第5期28卷 -页

作者： Gai-mei Wu Ji-long Zhou Mei-mei Lv Wei Xie song sun Chen Gao Wen-dong Wang Department of Chemical Physics University of Science and Technology of China Hefei 230026China National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230029 China

A kind of clay-supported K-Co-Mo catalyst was prepared by a sol-gel method combined with incipient wetness impregnation. The catalyst structure was characterized by X-ray diffraction, N2 adsorption-desorption, H2 temperature-programmed reduction, and X-ray photoelectron spectroscopy techniques and its catalytic performance for higher alcohol synthesis from syngas was investigated. The active components has a high dispersion on the clay support surface. The increase of the Mo loading promoted reduction of Mo6+ but had no significant influence on the reduction of Mo4+ and Co2+ species. After reduction, a kind of lower state Moδ+ (1<δ<4) species was observed on the surface. Compared with the unsupported catalyst, the clay supported K-Co-Mo catalysts showed much higher catalytic performance for alcohol formation. The reason can be explained that the supported catalyst have a high active surface area and the mesoporous structure prolonged the residence time of intermediates for alcohol formation to some extent, which promoted the formation of higher alcohols. The high activity of the catalyst reduced at 773 K may be attributed to the high content of Moδ+ (1<δ<4) species on the surface, which was regarded as the active site for the adsorption of nondissociative CO and responsible for the alcohol formation.

关键词： Higher alcohol synthesis Clay support K-Co-Mo catalyst Syngas

The analysis of genetic diversity and differentiation of six Chinese cattle populations using microsatellite markers

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Journal of Genetics and Genomics 2008年第1期35卷 25-32页

作者： Yongjiang Mao Hong Chang Zhangping Yang Liu Zhang Ming Xu Guobin Chang Wei sun Guangming song Dejun Ji Animal Science and Technology College Yangzhou University Yangzhou 225009 China

A total of 321 individuals from six cattle populations of four species in a bovine subfamily in China were studied using 12 pairs of microsatellite markers. The genetic diversities within and between populations were calculated. The phylogenetic trees were constructed by （δμ）^2 and DA distances, and the divergence times between populations were estimated by （δμ）^2. Altogether, 144 microsatellite alleles were detected including 24 private alleles and nine shared alleles. Chinese Holstein had the largest number of private alleles （10）, whereas Bohai black and Buffalo had the smallest number of private alleles （2）. Chinese Holstein showed the highest genetic variability. Its observed number of alleles （Na）, mean effective number of alleles （MNA）, and mean heterozygosity （He） were 7.7500, 4.9722, and 0.7719, respectively, whereas, the Buffalo and Yak showed low genetic variability. In the phylogenetic trees, Luxi and Holstein grouped first, followed by Bohai and Minnan. Yak branched next and buffalo emerged as the most divergent population from other cattle populations. Luxi and Bohai were estimated to have diverged 0.039-0.105 million years ago （MYA）, however, buffalo and Holstein diverged 0.501-1.337 MYA. The divergence time of Yak versus Minnan, Holstein and buffalo was 0.136-0.363, 0.273-0.729, and 0.326-0.600 MYA, respectively.

关键词： genetic diversity genetic differentiation microsatellite bovine subfamily

Legacy and emerging per-and polyfluoroalkyl substances(PFAS) in the atmosphere: A comprehensive review

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Science China Technological Sciences 2024年第10期67卷 3032-3050页

作者： QIAO BiTing song DongBao CHEN Hao YAO YiMing sun HongWen MOE Key Laboratory of Pollution Processes and Environmental Criteria College of Environmental Science and EngineeringNankai University

With long-term production and widespread application, per-and polyfluoroalkyl substances(PFAS) have been detected in various media worldwide, including the atmosphere. Since the gradual restriction and phase-out of C8perfluoroalkyl acids(PFAAs), environmental contamination by emerging PFAS substitutes such as short-chain PFAA homologues, perfluoroether carboxylic, and sulfonic acids has been reported. Although there has been extensive monitoring of emerging PFAS substitutes in the aquatic environment, few studies have conducted target analysis and nontarget screening(NTS) of emerging unknown PFAS in the atmosphere over the past decade. To fill the gap, this review focused on emerging PFAS in the atmosphere in addition to legacy PFAS. The reported sampling, pretreatment, and instrumental analysis methods for target analysis and NTS of both neutral and ionic PFAS in the atmosphere are summarized, along with the advantages and current limitations of different sampling and NTS methods for PFAS in the atmosphere. The global levels, composition, and spatiotemporal distribution characteristics of legacy and emerging PFAS in the atmosphere are summarized and their transport, transformation, and dry/wet deposition are elucidated. The review highlights the importance of developing and applying the all-in-one strategy integrating target, suspect screening, and NTS to gain insights into emerging PFAS in the atmosphere and provide a reference for future research.

关键词： emerging PFAS atmosphere nontarget screening spatiotemporal distribution fate

Multi-locomotion transition of tensegrity mobile robot under different terrains

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Science China(Technological Sciences) 2024年第2期67卷 536-557页

作者： YANG Qi LIU XinYu WANG PanFeng song YiMin sun Tao Key Laboratory of Mechanism Theory and Equipment Design(Tianjin University) Ministry of EducationTianjin UniversityTianjin 300350China

Knowing how to make a multi-locomotion robot achieve locomotion transition under different terrains is a challenging problem,especially for tensegrity robots with multi-locomotion *** this study,a motion planning method for the transition of a multi-locomotion tensegrity robot(hereafter TJUBot)under different terrains is *** robot can achieve four locomotion modes:earthworm-like,inchworm-like,tumbling,and sliding locomotion with only two *** models of the four locomotion modes under five typical terrains,including flat ground,confined space,obstacle,gap,and descending slope,are established using the energy ***,the kinematic characteristics(driving law and initial position)of the robot under these terrains are *** this basis,motion planning for the locomotion transition of TJUBot is conducted,which includes a perception strategy based on three laser sensors and a transition strategy under different *** driving laws of the two motors that can ensure the effective locomotion transition of TJUBot under different terrains are naturally ***,experiments are *** demonstrate that the robot can achieve effective locomotion transition when the motion planning method is used.

关键词： multi-locomotion robot tensegrity kinematic modeling locomotion transition

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小儿外科实习带教方法的探讨

中国继续医学教育 2024年第14期16卷 194-198页

作者：张清池杨家健章国栋张敏张中喜孙松宋再厦门市儿童医院/复旦大学附属儿科医院厦门医院普外科福建厦门361006 复旦大学附属儿科医院普外科上海201102

临床实习是医学生从学生角色转变成临床医生的重要阶段,小儿外科因为其病种和儿童患者群体的特殊性,临床实习带教增加诸多困难。如何让实习医师在短时间内提高实习生对小儿外科常见疾病症状和体征的客观感知,从而提高小儿外科实习的质量... 详细信息

临床实习是医学生从学生角色转变成临床医生的重要阶段,小儿外科因为其病种和儿童患者群体的特殊性,临床实习带教增加诸多困难。如何让实习医师在短时间内提高实习生对小儿外科常见疾病症状和体征的客观感知,从而提高小儿外科实习的质量,是专科儿童医院小儿外科临床教学面临的重要问题。文章介绍了厦门市儿童医院外科通过构建高水平的带教团队、模拟教学和翻转课堂的方式来提高小儿外科实习教育的质量。首先,通过严格的带教老师选拔标准,师资定期培训和多维度评价来建立高素质的带教老师团队。其次,多样化的教学方式包括模块化培训、仿真模拟教学和有针对性手术技能培训,提高实习医师的操作技能。最后,利用翻转课堂的方式学习小儿外科基本疾病和处理原则,提高实习医师主动学习和自助学习能力。这些策略和经验有望提高小儿外科实习教育的质量,为培养更多高水平的小儿外科医生提供支持。

关键词：小儿外科临床实习模拟教学模块化培训仿真模拟教学翻转课堂手术技能培训

Asymmetric transfer hydrogenation of ketones catalyzed by nickel complex with new PNO-type ligands

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Chinese Chemical Letters 2012年第5期23卷 533-536页

作者： Zhen Rong Dong Yan Yun Li Shen Luan Yu Guo song sun Jing Xing Gao State Key Laboratory for Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Guangxi Research Institute of Chemical Industry Nanning 530001China

The new polydentate mixed-N,P,O chiral ligands have been synthesized by the condensation of bis（o-formylphenyl）- phenylphosphane and R-phenylglycinol in CHCl_3,and fully characterized by IR,NMR and EIMS *** ligands were employed with a simple Ni complex Ni（PPh_s）_2Cl_2 in situ as catalytic systems for asymmetric transfer hydrogenation of ketones,and the corresponding optical alcohols were obtained with up to 84%ee under mild conditions.

关键词： Nickel complex NPO-type ligand Asymmetric transfer hydrogenation Ketones

Can serum immunoglobulin G4 levels and age serve as reliable predictors of relapse in autoimmune pancreatitis?

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World Journal of Gastroenterology 2024年第5期30卷 512-515页

作者： Jun-Min song Si-Yu sun Department of Gastroenterology Shengjing Hospital of China Medical UniversityShenyang 110004Liaoning ProvinceChina

We are writing in response to the paper published in the World Journal of Gastroenterology by Zhou et *** authors identified higher serum immunoglobulin(Ig)G4 levels and age over 55 years as independent risk factors for disease *** notable strengths,it is crucial to address potential ***,the cohort study included 189 patients with autoimmune pancreatitis(AIP)type 1(with higher IgG4 seropositivity and higher relapse)and 24 with type 2(with lower IgG4 seropositivity and lower relapse).Consequently,most,if not all,AIP type 2 patients were assigned to the normal group,possibly inflating the association of higher serum IgG4 levels with relapse and potentially exaggerating the association of older age with ***,the authors did not provide sufficient details regarding AIP diagnosis,such as the ratio of definitive vs probable cases and the proportion of *** cases where histological evidence is unavailable or indeterminate,AIP type 2 may be misdiagnosed as definitive type 1,and type 1 may also be misdiagnosed as probable type 2,particularly in cases with normal or mildly elevated serum IgG4 ***,in this retrospective study,approximately one-third of the consecutive patients initially collected were excluded for various ***,the impact of nonrandom exclusion on relapse outcomes should be carefully *** conclusion,the paper by Zhou et al offers plausible,though not entirely compelling,evidence suggesting a predictive role of elevated serum IgG4 levels and advanced age in AIP *** foundation for future investigations lies in ensuring a reliable diagnosis and accurate disease subtyping,heavily dependent on obtaining histological *** this regard,endoscopic ultrasound-guided fine-needle biopsy emerges as a pivotal component of the diagnostic process,contributing to mitigating biases in future explorations of the disease.

关键词： Autoimmune pancreatitis Immunoglobulin Endoscopic ultrasound Relapse Age

Estimates of net primary productivity and actual evapotranspiration over the Tibetan Plateau from the Community Land Model version 4.5 with four atmospheric forcing datasets

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Journal of Plant Ecology 2024年第4期17卷 70-89页

作者： Shan Lin Kewei Huang Xiangyang sun Chunlin song Juying sun Shouqin sun Genxu Wang Zhaoyong Hu State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China Hubei Key Laboratory of Basin Water Security Changjiang SurveyPlanningDesign and Research Co.Ltd.Wuhan 430010China Research Unit Forest Dynamics Swiss Federal Research Institute for ForestSnow and Landscape Research WSLBirmensdorf 8903Switzerland

The accuracy of the simulation of carbon and water processes largely relies on the selection of atmospheric forcing datasets when driving land surface models(LSM).Particularly in high-altitude regions,choosing appropriate atmospheric forcing datasets can effectively reduce uncertainties in the LSM ***,this study conducted four offline LSM simulations over the Tibetan Plateau(TP)using the Community Land Model version 4.5(CLM4.5)driven by four state-of-the-art atmospheric forcing *** performances of CRUNCEP(CLM4.5 model default)and three other reanalysis-based atmospheric forcing datasets(***,GSWP3 and WFDEI)in simulating the net primary productivity(NPP)and actual evapotranspiration(ET)were evaluated based on in situ and gridded reference *** with in situ observations,simulated results exhibited determination coefficients(R2)ranging from 0.58 to 0.84 and 0.59 to 0.87 for observed NPP and ET,respectively,among which GSWP3 and ITPCAS showed superior *** the plateau level,CRUNCEP-based simulations displayed the largest bias compared with the reference NPP and ***3-based simulations demonstrated the best performance when comprehensively considering both the magnitudes and change trends of TP-averaged NPP and *** simulated ET increase over the TP during 1982-2010 based on ITPCAS was significantly greater than in the other three simulations and reference ET,suggesting that ITPCAS may not be appropriate for studying long-term ET changes over the *** results suggest that GSWP3 is recommended for driving CLM4.5 in conducting long-term carbon and water processes simulations over the *** study contributes to enhancing the accuracy of LSM in water-carbon simulations over alpine regions.

关键词： land surface model carbon cycle water cycle high altitude Community Land Model version 4.5

Neural Parse Combination

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Journal of Computer Science & Technology 2017年第4期32卷 749-757页

作者： Lin-Er Yang Mao-song sun Yong Cheng Jia-Cheng Zhang Zheng-Hao Liu Huan-Bo Luan Yang Liu Department of Computer Science and Technology Tsinghua University Beijing 100084 China State Key Laboratory of Intelligent Technology and Systems Tsinghua University Beijing 100084 China Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China Jiangsu Collaborative Innovation Center for Language Ability Jiangsu Normal University Xuzhou 221009 China Institute for Interdisciplinary Information Sciences Tsinghua University Beijing 100084 China

Analyzing the syntactic structure of natural languages by parsing is an important task in artificial intelligence. Due to the complexity of natural languages, individual parsers tend to make different yet complementary errors. We propose a neural network based approach to combine parses from different parsers to yield a more accurate parse than individual ones. Unlike conventional approaches, our method directly transforms linearized candidate parses into the ground-truth parse. Experiments on the Penn English Treebank show that the proposed method improves over a state-of-the-art parser combination approach significantly.

关键词： neural network parsing parse combination