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Combination of a reaction cell and an ultra-high vacuum system for the in situ preparation and characterization of a model catalyst

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Nuclear Science and Techniques 2023年第5期34卷 13-21页

作者： Yi-Jing Zang Shu-Cheng Shi Yong han Hui Zhang Wei-Jia Wang Peng liu Mao ye zhi liu State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China

An in-depth understanding of the structure-activity relationship between the surface structure,chemical composition,adsorption and desorption of molecules,and their reaction activity and selectivity is necessary for the rational design of high-performance ***,we present a method for studying catalytic mechanisms using a combination of in situ reaction cells and surface science *** proposed system consists of four parts:preparation chamber,temperatureprogrammed desorption(TPD)chamber,quick load-lock chamber,and in situ reaction *** preparation chamber was equipped with setups based on the surface science techniques used for standard sample preparation and characterization,including an Ar+sputter gun,Auger electron spectrometer,and a low-energy electron *** a well-defined model catalyst was prepared,the sample was transferred to a TPD chamber to investigate the adsorption and desorption of the probe molecule,or to the reaction cell,to measure the catalytic activity.A thermal desorption experiment for methanol on a clean Cu(111)surface was conducted to demonstrate the functionality of the preparation and TPD ***,the repeatability of the in situ reaction cell experiment was verified by CO_(2) hydrogenation on the Ni(110)*** a reaction pressure of 800 Torr at 673 K,turnover frequencies for the methanation reaction and reverse water-gas shift reaction were 0.15 and 7.55 Ni atom^(-1) s^(-1),respectively.

关键词： Surface science Model catalysts Ultra-high vacuum Temperature-programmed desorption In situ reaction cell

Exploration of pathogenic microorganism within the small intestine of necrotizing enterocolitis

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World Journal of Pediatrics 2024年第2期20卷 165-172页

作者： Yan Wang Kun jiang Qiao Xia Xia Kang shan Wang Ji-Hong Yu Wen-Feng Ni Xiao-Qin Qi Ying-na Zhang Jin-Bao han Gang liu Lei Hou zhi-Chun Feng liu-Ming Huang Clinical Biobank Center Medical Innovation Research Division of ChinesePLA General HospitalBeijingChina Institute of Basic Medical Sciences Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Senior Department of Pediatrics The Seventh Medical Center of PLA General HospitalBeijing 100700China Department of Neurology The First Medical CenterChinese PLA General HospitalBeijing 100853China Department of Emergency Center National Center for Children's HealthBeijing Children's HospitalCapital Medical UniversityBeijing 100045China

Background Necrotizing enterocolitis(NEC)is the most common severe gastrointestinal emergency in *** designed this study to identify the pathogenic microorganisms of NEC in the microbiota of the small intestine of *** Using the 16S ribosomal Dna(rDna)sequencing method,we compared and analyzed the structure and diversity of microbiotas in the intestinal feces of different groups of neonates:patients undergoing jejunostomy to treat NEC(NP group),neonates undergoing jejunostomy to treat other conditions(NN group),and neonates with NEC undergoing conservative treatment(NC group).We took intestinal feces and saliva samples from patients at different time *** The beta diversities of the NP,NN,and NC groups were all *** comparing the beta diversities between different time points in the NP group,we found similar beta diversities at time points El to E3 but significant differences between the E2-E3 and E4 time points:the abundances of Klebsiella and Enterococcus(Proteobacteria)were higher at the E1-E3 time points;the abundance of Escherichia-Shigella(Proteobacteria)increased at the E2 time point,and the abundance of Klebsiella decreased significantly,whereas that of Streptococcus increased significantly at the E4 time *** Our results suggest that the pathological changes of intestinal necrosis in the small intestine of infants with NEC are not directly caused by excessive proliferation of pathogenic bacteria in the small *** sources of microbiota in the small intestine of neonates,especially in premature infants,may be affected by multiple factors.

关键词： Microbiota Necrotizing enterocolitis-Small intestine 16S rDna

A 4-GS/s 8-bit two-channel time-interleaved folding and interpolating ADC

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Science China(Information Sciences) 2014年第1期57卷 291-296页

作者： jiang Fan WU DanYu zhou Lei WU Jin JIN zhi liu XinYu Institue of Microelectronics Chinese Academy of Sciences

Ultra high speed and moderate resolution ADCs with low latency are demanded in many applications.A 4-GS/s 8-bit ADC is implemented in the 0.35μm SiGe BiCMOS *** is based on the two-channel time-interleaved architecture and each sub-ADC employs the two-stage cascaded folding and interpolating topology which guarantees the low-latency *** circuits are introduced to compensate for the mismatch between the two *** whole chip area is about 4.0×4.0(mm2).The ADC exhibits DNL of 0.26/0.34 LSB and INL of 0.96/0.92 *** ENOB is 7.1 bits and the SFDR is about 56 dB at10.1 MHz *** SNDR is above 42 dB over the first and the second Nyquist *** SFDR is above45 dB over the first Nyquist zone and the second Nyquist *** ERBW is about 1.4 GHz.

关键词： time-interleaved folding interpolating analog-to-digital converter(ADC) track-and-hold ampli-fier

Microstructure and Properties of 7075Al Alloy Fabricated by Directly Combined of Spray Forming and Continuous Extrusion Forming under Different Atomization Gas Pressures

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Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 804-812页

作者： ye-Gao Chen Yi Zhong jiang-Cheng Yin Li-Qiang Wang Li-na liu Huan Yang Ying-Li liu Faculty of Materials Science and Engineering Kunming University of Science and Technology

A new process consisting of the spray forming and the continuous extrusion forming for manufacturing 7075A1 alloy was proposed. The microstructure evolution, mechanical properties and the resistance to stress corrosion cracking of the alloy were studied. The results indicate that the spray forming process induces obviously grain refinement and greatly lower segregation microstructure. Besides, the Conform process produces finer grains and conduces to more uniform distribution of the precipitates of A1Cu and MgZn2 phases. The fabricated alloy shows good comprehensive mechanical properties and superb performance of stress corrosion resistance. Moreover, a better combination of the mechanical properties and the resistance to stress corrosion cracking could then be obtained under a certain condition of atomization gas pressure of 0.19 MPa. The enhanced properties are attributed to the following factors, which include the grain refinement, the fine and homogeneous distribution of A1Cu and MgZn2 phases, the high density of the extruded products, as well as the discontinuous distribution of the grain boundaries after retrogression and reaging （RRA） heat treatment.

关键词： 7075A1 alloy Spray forming Continuous extrusion forming Microstructure Property

Expression of Bcl-2 and NF-κB in brain tissue after acute renal ischemia-reperfusion in rats

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Asian Pacific Journal of Tropical Medicine 2014年第5期7卷 386-389页

作者： na Zhang Gen-Yang Cheng Xian-zhi liu Feng-jiang Zhang Department of Neurosurgery First Affiliated Hospital of Zhengzhou University Department of Nephrology First Affiliated Hospital of Zhengzhou University

Objective:To investigate the effect of acute renal ischemia reperfusion on brain ***:Fourty eight rats were randomly divided into four groups(n=12):sham operation group,30 min ischemia 60 min reperfusion group,60 min ischemia 60 min reperfusion group,and120 min ischemia 60 min reperfusion *** brain tissues were taken after the *** assay was used to detect the brain cell apoptosis,and western blot was used to detect the expression of apoptosis-related proteins and inflammatory ***:Renal ischemiareperiusion induced apoptosis of brain tissues,and the apoptosis increased with prolongation of ischemia *** detection at the molecular level showed decreased Bcl-2 expression,increased Bax expression,upreguiated expression of NF- κB and its downstream factor COX-2/***:Acute renal ischemia-reperfusion can cause brain tissue damage,manifested as induced brain tissues apoptosis and inflammation activation.

关键词： Acute renal ischemia reperfusion Brain tissue damage Bcl-2 NF-κB

Insulin-like growth factor-1 induces lymphangiogenesis and facilitates lymphatic metastasis in colorectal cancer

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World Journal of Gastroenterology 2013年第43期19卷 7788-7794页

作者： Zhen-Jun Li Xiao-jiang Ying Hong-Liang Chen Ping-jiang ye zhi-Liang Chen Gang Li Hua-Feng jiang jiang liu Shu-Zhen zhou Department of Colorectal Surgery Shaoxing People’s Hospital Shaoxing Hospital of Zhejiang University

AIM:To investigate the expression of insulin-like growth factor-1(IGF-1)/insulin-like growth factor-1 receptor(IGF-1R)in colorectal cancer(CRC)tissues and to analyze their correlation with lymphangiogenesis and lymphatic ***:Immunohistochemistry was used to evaluate IGF-1 and IGF-1R expression and lymphatic vessel density(LVD)in 40 CRC *** correlation between IGF-1/IGF-1R and LVD was *** of IGF-1 on migration and invasion of CRC cells were examined using transwell chamber assays.A LoVo cell xenograft model was established to further detect the role of IGF-1 in CRC lymphangiogenesis in vivo. RESULTS:Elevated IGF-1 and IGF-1R expression in CRC tissues was correlated with lymph node metastasis(r=0.715 and 0.569,respectively,Pnaling induces tumorassociated lymphangiogenesis and contributes to lymphatic metastasis of CRC.

关键词： Colorectal cancer Insulin-like growth factor-1 Insulin-like growth factor-1 receptor Lymphangiogenesis Lymphatic metastasis

Construction of a novel brittleness index equation and analysis of anisotropic brittleness characteristics for unconventional shale formations

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Petroleum Science 2020年第1期17卷 70-85页

作者： Ke-Ran Qian Tao liu Jun-zhou liu Xi-Wu liu zhi-Liang He Da-Jian jiang State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing 100083China Sinopec Key Laboratory of Seismic Elastic Wave Technology Beijing 100083China Key Laboratory of Shale Oil and Gas Exploration and Production SINOPECBeijing 100083China Ministry of Science and Technology SINOPECBeijing 100728China Sinopec Petroleum Exploration and Production Research Institute Beijing 100083China

The brittleness prediction of shale formations is of interest to researchers *** methods of brittleness prediction are usually based on isotropic models while shale is *** order to obtain a better prediction of shale brittleness,our study firstly proposed a novel brittleness index equation based on the Voigt–Reuss–Hill average,which combines two classical isotropic *** proposed method introduces upper and lower brittleness bounds,which take the uncertainty of brittleness prediction into *** addition,this method can give us acceptable predictions by using limited input ***,an anisotropic rock physics model was *** parameters were introduced into our model,which can be used to simulate the lamination of clay minerals and the dip angle of *** addition,rock physics templates have been built to analyze the sensitivity of brittleness ***,the effects of kerogen,pore structure,clay lamination and shale formation dip have been investigated in terms of *** prediction shows that the vertical/horizontal Young’s modulus is always below one while the vertical/horizontal Poisson’s ratio(PR)can be either greater or less than *** study finds different degrees of shale lamination may be the explanation for the random distribution of Vani(the ratio of vertical PR to horizontal PR).

关键词： Brittleness Shale Rock Physics Anisotropy Voigt–Reuss–Hill average

NextPolish2:A Repeat-aware Polishing Tool for Genomes Assembled Using HiFi Long Reads

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 105-109页

作者： jiang Hu Zhuo Wang Fan Liang shan-Lin liu Kai ye De-Peng Wang School of Automation Science and Engineering Faculty of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an 710049China GrandOmics Biosciences Beijing 102206China Department of Entomology College of Plant ProtectionChina Agricultural UniversityBeijing 100193China

The high-fidelity(HiFi)long-read sequencing technology developed by PacBio has greatly improved the base-level accuracy of genome ***,these assemblies still contain base-level errors,particularly within the error-prone regions of HiFi long *** genome polishing tools usually introduce overcorrections and haplotype switch errors when correcting errors in genomes assembled from HiFi long ***,we describe an upgraded genome polishing tool-NextPolish2,which can fix base errors remaining in those“highly accurate”genomes assembled from HiFi long reads without introducing excessive overcorrections and haplotype switch *** believe that NextPolish2 has a great significance to further improve the accuracy of telomere-to-telomere(T2T)***2 is freely available at https://***/Nextomics/NextPolish2.

关键词： Telomere-to-telomere Genome assembly Genome polishing Error correction HiFi long read

EZH2 and STAT6 expression profiles are correlated with colorectal cancer stage and prognosis

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World Journal of Gastroenterology 2010年第19期16卷 2421-2427页

作者： Wang, Cheng-Gang ye, Ying-jiang Yuan, Jing liu, Fang-Fang Zhang, Hui Wang, shan Beijing Univ Dept Surg Gastroenterol Surg Oncol Lab Peoples Hosp Beijing 100044 Peoples R China Chinese Peoples Liberat Army Hosp Dept Pathol Beijing 100036 Peoples R China Beijing Univ Peoples Hosp Dept Pathol Beijing 100044 Peoples R China

AIM: To investigate the role of enhancer of zeste homologue 2 (EZH2) and STAT6 immunohistochemistry in the evaluation of clinical stages and prognosis of colorectal cancer (CRC). METHODS: The expression patterns were examined by immunohistochemistry in both tumor and adjacent non-neoplastic tissues of 119 CRC patients who underwent operation during the time period from 2002 to 2004. RESULTS: The positive rates of EZH2 and STAT6 in CRC cases were 69.7% (83 of 119) and 60.5% (72 of 119), respectively, and there was signifi cant differ-ence when compared with tumor adjacent non-neoplastic tissues (P han those with EZH2-negative or STAT6-negative expression (P = 0.002 and P = 0.005, respectively). Co-expression of EZH2 and STAT6 showed signifi cantly higher levels in CRC cases of high clinical TNM stages (P = 0.001), and the expression of STAT6 was also correlated with lymph node metastasis and distant metastasis (P = 0.001 and P = 0.016, respectively). Multivariate analysis revealed that EZH2 expression was an independent prognostic indicator of CRC (P = 0.039). CONCLUSION: EZH2 and STAT6 expressions have significant values in distinguishing clinical stages of CRC and predicting the prognosis of the patients.

关键词： Colorectal Neoplasms Enhancer of zeste homologue 2 STAT6 Immunohistochemistry