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Can Hydrogen be Incorporated inside Silicon Nanocrystals?

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Chinese Physics Letters 2012年第7期29卷 254-256页

作者： NI Zhen-Yi PI xiao-Dong yang De-ren State Key Laboratory of Silicon Materials and Department of Materials Science and Engineering Zhejiang UniversityHangzhou 310027

Hydrogen is omnipresent during the synthesis and processing of silicon nanocrystals (Si NCs).It is generally assumed that the incorporation of hydrogen leads to the passivation of Si dangling bonds at the NC ***,it is also speculated that hydrogen may be incorporated inside Si *** this work the formation energy and probability of hydrogen in its three configurations,i.e.,hydrogen molecules,bond-centered atomic hydrogen,and antibonding atomic hydrogen,are calculated to rigorously evaluate the incorporation of hydrogen inside Si *** find that hydrogen cannot be incorporated inside Si NCs with a diameter of a few nanometers at temperatures up to 1500K.

关键词： hydrogen rigorous bonding

Corrosion Behavior of the Ni-Cr-Fe Base Superalloy GH984G in a Synthetic Coal Ash and Flue Gas Environment

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Acta Metallurgica Sinica(English Letters) 2017年第9期30卷 863-868页

作者： Guang-Ming Liu Hua-Chun yang Qin Liang xiao-Chuan yang Shan-Ping ren Jian-Hang Huang School of Materials Science and Engineering Nanchang Hangkong University Dongfang Boiler Group Co. Ltd Material Research Institute

The corrosion behavior of the new Ni-Cr-Fe base superalloy GH984G in a synthetic coal ash and flue gas environments was studied at 700 ℃. The results showed that the corrosion rate was slow during the initial corrosion stage, then followed by a stage of faster mass loss. During the corrosion test, the scale trended to spall slightly, resulting in the formation of corrosion pits on the sample surfaces. The main corrosion products were identified as NiFeCrO4 and a small amount of Cr2O3. The scale microstructure involved the presence of three corrosion layers. The outer layer contained Cr, Ni, Fe, O and a small amount of S. Many micro-cracks were detected in the Cr-rich intermediate oxide layer. The inner corrosion layer was thin and rich in S. Internal sulfidation and internal oxidation occurred in the substrate. Because of its relatively high Cr content, the GH984G superalloy exhibited a good corrosion resistance under the test conditions.

关键词： Ni-Fe-Cr base superalloy Coal ash SO2 Corrosion

Artificial intelligence in small intestinal diseases:Application and prospects

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World Journal of Gastroenterology 2021年第25期27卷 3734-3747页

作者： Yu yang Yu-Xuan Li ren-Qi Yao xiao-Hui Du Chao ren Department of General Surgery Chinese People’s Liberation Army General HospitalBeijing 100853China Trauma Research Center The Fourth Medical Center and Medical Innovation Research Division of the Chinese People‘s Liberation Army General HospitalBeijing 100048China Department of Burn Surgery Changhai HospitalNaval Medical UniversityShanghai 200433China

The small intestine is located in the middle of the gastrointestinal tract,so small intestinal diseases are more difficult to diagnose than other gastrointestinal ***,with the extensive application of artificial intelligence in the field of small intestinal diseases,with its efficient learning capacities and computational power,artificial intelligence plays an important role in the auxiliary diagnosis and prognosis prediction based on the capsule endoscopy and other examination methods,which improves the accuracy of diagnosis and prediction and reduces the workload of *** this review,a comprehensive retrieval was performed on articles published up to October 2020 from PubMed and other *** the application status of artificial intelligence in small intestinal diseases was systematically introduced,and the challenges and prospects in this field were also analyzed.

关键词： Artificial intelligence Machine learning Deep learning Prognosis prediction Small intestinal diseases

Enhanced mechanical properties and formability of 316L stainless steel materials 3D-printed using selective laser melting

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International Journal of Minerals,Metallurgy and Materials 2019年第11期26卷 1396-1404页

作者： xiao-qin yang Ying Liu Jin-wen Ye ren-quan Wang Ting-chuan Zhou Bin-yang Mao College of Materials Science and Engineering Sichuan University

This study is conducted to develop an innovative and attractive selective laser melting(SLM)method to produce 316 L stainless steel materials with excellent mechanical performance and complex part *** this work,the subregional manufacturing strategy,which separates the special parts from the components using an optimized process,was *** results showed that produced 316 L materials exhibited superior strength of^755 MPa and good *** the as-built parts,austenite with preferred orientation of the(220)plane,δ-ferrite,and a small amount of CrO phases were *** addition,the crystal size was fine,which contributed to the enhancement of the parts’mechanical *** structural anisotropy mechanism of the materials was also investigated for a group of half-sized samples with variable inclination *** technique was used to fabricate a set of impellers with helical bevels and high-precision planetary gears,demonstrating its strong potential for use in practical applications.

关键词： 316L stainless steel selective laser melting formability mechanical properties microstructure

Exploring choices of early nutritional support for patients with sepsis based on changes in intestinal microecology

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World Journal of Gastroenterology 2023年第13期29卷 2034-2049页

作者： xiao-Juan yang xiao-Hong Wang Ming-Yue yang Hong-Yan ren Hui Chen xiao-Ya Zhang Qin-Fu Liu Ge yang Yi yang xiao-Jun yang Department of Critical Care Medicine General Hospital of Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina School of Clinical Medicine Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Department of Emergency Medicine Affiliated Hospital of Jining Medical UniversityJining 272030Shandong ProvinceChina Shanghai Mobio Biomedical Technology Co. Ltd.Shanghai 201318China Department of Critical Care Medicine Southeast University School of MedicineZhongda HospitalSchool of MedicineSoutheast UniversityNanjing 210009Jiangsu ProvinceChina

BACKGROUND Sepsis exacerbates intestinal microecological disorders leading to poor *** modalities of nutritional support can improve nutrition,immunity,and intestinal *** To identify the optimal modality of early nutritional support for patients with sepsis from the perspective of intestinal *** Thirty patients with sepsis admitted to the intensive care unit of the General Hospital of Ningxia Medical University,China,between 2019 and 2021 with indications for nutritional support,were randomly assigned to one of three different modalities of nutritional support for a total of 5 d:Total enteral nutrition(TEN group),total parenteral nutrition(TPN group),and supplemental parenteral nutrition(SPN group).Blood and stool specimens were collected before and after nutritional support,and changes in gut microbiota,short-chain fatty acids(SCFAs),and immune and nutritional indicators were detected and compared among the three *** In comparison with before nutritional support,the three groups after nutritional support presented:(1)Differences in the gut bacteria(Enterococcus increased in the TEN group,Campylobacter decreased in the TPN group,and Dialister decreased in the SPN group;all Prent trends in SCFAs(the TEN group showed improvement except for Caproic acid,the TPN group showed improvement only for acetic and propionic acid,and the SPN group showed a decreasing trend);(3)significant improvement of the nutritional and immunological indicators in the TEN and SPN groups,while only immunoglobulin G improved in the TPN group(all P<0.05);and(4)a significant correlation was found between the gut bacteria,SCFAs,and nutritional and immunological indicators(all P<0.05).CONCLUSION TEN is recommended as the preferred mode of early nutritional support in sepsis based on clinical nutritional and immunological indicators,as well as changes in intestinal microecology.

关键词： Sepsis Nutritional support Intestinal microecology Short-chain fatty acids Nutritional and immunological indicators Total enteral nutrition Total parenteral nutrition Supplemental parenteral nutrition

Experimental study on motion and mechanical characteristics of the vertical wheel in the rock-breaking process

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Petroleum Science 2023年第1期20卷 495-506页

作者： Yan yang Ying-Xin yang Hai-Tao ren Qing-Liang Qi Ze-Quan Huang Chun-xiao Zhou International Faculty of Applied Technology Yibin UniversityYibinSichuan 644000China College of Mechanical and Electrical Engineering Southwest Petroleum UniversityChengduSichuan 610500China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduSichuan 610500China Faculty of Intelligence Manufacturing Yibin UniversityYibinSichuan 644000China College of Engineering Southwest Petroleum UniversityNanchongSichuan 637001China

Polycrystalline diamond compact(PDC)drill bit often performs with low ROP,short service life and poor stability under complicated and difficult to drill ***,a vertical wheel PDC bit is proposed,which is a new drill bit technology applying an integrated unit combining the tooth wheel and the rotary shaft ***,the experiments on motion and mechanical characteristics of the vertical wheel under the conditions of tooth shape and number of teeth,normal deflection angle of the wheel,and different cutting depth were carried out using variable parameter experimental device,and the movement,force law,and crushing specific work of vertical wheel under different experimental conditions were *** comparative experiments of PDC cutting rock breaking under the conditions of parallel cutting of PDC unit and pre-damage of the wheel were also carried out,and the cutting load of PDC teeth under pre-damage conditions is between 38.72% and 70.95%lower than that of parallel cutting was ***,a comparative experiment of indoor drilling between vertical wheel PDC bit and conventional PDC bit was carried *** show than when drilling in gravel rock,under the same WOB,the torque response of vertical wheel PDC bit is equivalent to that of the PDC bit,while the ROP of vertical wheel PDC bit is 22.94%-53.33% higher than that of conventional PDC bit,and the threedimensional acceleration of the vertical wheel PDC bit is 19.17%-76.23% of that of the PDC *** experimental results contribute to a better understanding of vertical wheels and provide technical support for their use in PDC bits.

关键词： Difficult to drill formation Vertical wheel Vertical wheel PDC bit Rock-breaking mechanism Pre-damage

Comprehensive multi-omics profiling identifies novel molecular subtypes of pancreatic ductal adenocarcinoma

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Genes & Diseases 2024年第6期11卷 315-330页

作者： Xing Wang Jinshou yang Bo ren Gang yang xiaohong Liu Ruiling xiao Jie ren Feihan Zhou Lei You Yupei Zhao Department of General Surgery Peking Union Medical College HospitalPeking Union Medical CollegeChinese Academy of Medical SciencesBeijing 100023China Key Laboratory of Research in Pancreatic Tumor Chinese Academy of Medical SciencesBeijing 100023China National Science and Technology Key Infrastructure on Translational Medicine in Peking Union Medical College Hospital Beijing 100023China

Pancreatic cancer,a highly fatal malignancy,is predicted to rank as the second leading cause of cancer-related death in the next *** highlights the urgent need for new insights into personalized diagnosis and *** molecular subtypes of pancreatic cancer were well established in genomics and transcriptomics,few known molec-ular classifications are translated to guide clinical strategies and require a paradigm ***,chronically developing and continuously improving high-throughput technologies and systems serve as an important driving force to further portray the molecular landscape of pancreatic cancer in terms of epigenomics,proteomics,metabonomics,and ***,a more comprehensive understanding of molecular classifications at multiple levels using an integrated multi-omics approach holds great promise to exploit more potential ther-apeutic *** this review,we recapitulated the molecular spectrum from different omics levels,discussed various subtypes on multi-omics means to move one step forward towards bench-to-beside translation of pancreatic cancer with clinical impact,and proposed some methodological andscientific challengesinstore.

关键词： Molecular characterization Molecular subtyping Multi-omics Pancreatic cancer Precision medicine

Self-diffusion coefficients of organic solvents in linear and branched high density polyethylene particles measured by PFG NMR

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Chinese Chemical Letters 2008年第1期19卷 110-114页

作者： xiao Wei Yan xiao Hong ren Siegfried Stap Jing Dai Wang Yong Rong yang Department of Chemical Engineering Zhejiang University Hangzhou 310027 China FG Technische Physik ll/Polymerphysik Fakultat fiir Mathematik und Naturwissenschaften Technische Universitiit Ilmenau Postfach 100565 D-98684 Ilmenau Germany Institut fiir Technische Chemie und Makromolekulare Chemie RWTH Aachen University Worringerweg 1 D-52056 Aachen Germany

Pulsed field gradient nuclear magnetic resonance （PFG NMR） has been performed to study the diffusion of organic solvents into semicrystalline polyethylene particles. Self-diffusion coefficients in different domains of the sample can be extracted through a bi- exponential fit to the echo intensity attenuation, which allows the precise determination of the tortuosity of the polyethylene particles. Further exploration comes from the measurements with branched polyethylene particles and it was found that the diffusion in polymer phase contributed significantly to the slow component of the exponential decay curve. 2007 Jing Dai Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Self-diffusion coefficients Pulsed field gradient NMR Tortuosity Polyethylene particle

Effect of solute Ce,Mn,and Si on mechanical properties of silicon steel:insights from DFT calculations

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Journal of Iron and Steel Research International 2024年第3期31卷 700-709页

作者： Xiang-jun Liu Ji-chun yang Hui-ping ren xiao-bin Jia Ming-yi Zhang Chang-qiao yang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resource Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina Inner Mongolia North Heavy Industries Group Co. Ltd.Baotou 014010Inner MongoliaChina Inner Mongolia Metal Material Research Institute Baotou 014010Inner MongoliaChina

The influence of solute Ce,Mn,and Si on the mechanical properties of silicon steel was investigated by first-principles ***,Mn,and Si can all be solubilized in Fe *** significantly reduces the incompressibility and rigidity of the system but also significantly improves the toughness and *** effect of Mn on mechanical properties of the system is not *** has a significant effect on the improvement in incompressibility and rigidity but a limited effect on the improvement in toughness and *** metallic bond strength of Fe-Ce,Fe-Mn,and Fe-Si doped systems is weaker than that of the pure Fe system,which can be used to explain the reduction in the incompressibility and rigidity of these doped *** relatively high electron cloud density in the doped system may be responsible for the increase in toughness.

关键词： Silicon steel Rare earth First-principles calculation Elastic modulus Electronic structure