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Effect of Mn addition on microstructure and mechanical properties of GX40CrNiSi25-12 austenitic heat resistant steel

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China Foundry 2024年第3期21卷 205-212页

作者： Guan-yu Jiang Meng-wu Wu Xiao-guang Yang Hui Wang yu-yuan Zhu Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina Wescast Industries(China)Co. Ltd.Wuhan 430100China

Three types of steels were designed on the basis of GX40CrNiSi25-12 austenitic heat resistant steel by adding different Mn contents(2wt.%,6wt.%,and 12wt.%).Thermodynamic calculation,microstructure characterization and mechanical property tests were conducted to investigate the effect of Mn addition on the microstructure and mechanical properties of the austenitic heat resistant *** show that the matrix structure in all the three types of steels at room temperature is completely *** NbC and M_(23)C_(6)precipitate at grain boundaries of austenite *** the increase of Mn content,the number of carbides increases and their distribution becomes more *** the Mn content increases from 1.99%to 12.06%,the ultimate tensile strength,yield strength and elongation increase by 14.6%,8.0%and 46.3%,*** improvement of the mechanical properties of austenitic steels can be explained by utilizing classic theories of alloy strengthening,including solid solution strengthening,precipitation strengthening,and grain *** increase in alloy strength can be attributed to solid solution strengthening and precipitation strengthening caused by the addition of *** improvement of the plasticity of austenitic steels can be explained from two aspects:grain refinement and homogenization of precipitated phases.

关键词： austenitic heat resistant steel manganese microstructure mechanical properties

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Predicting submerged vegetation drag with a machine learning-based method

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Journal of Hydrodynamics 2024年第3期36卷 534-545页

作者： Meng-yang Liu Hong-wu Tang Sai-yu yuan Jing Yan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(H^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

Chronic sleep deprivation induces alterations in DNA and RNA modifications by liquid chromatography-mass spectrometry analysis

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Chinese Chemical Letters 2024年第8期35卷 413-417页

作者： Tian Feng yun-Ling Gao Di Hu Ke-yu yuan Shu-Yi Gu Yao-Hua Gu Si-yu yu Jun Xiong yu-Qi Feng Jie Wang Bi-Feng yuan School of Public Health Research Center of Public HealthRenmin Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China Department of Radiation and Medical Oncology Zhongnan Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China Key Laboratory of Magnetic Resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Center for Magnetic Resonance in WuhanWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences-Wuhan National Laboratory for OptoelectronicsWuhan 430071China University of Chinese Academy of Sciences Beijing 101408China Institute of Neuroscience and Brain Diseases Xiangyang Central HospitalAffiliated Hospital of Hubei University of Arts and ScienceXiangyang 441000China Phase I Clinical Trial Laboratory Zhongnan Hospital of Wuhan UniversityWuhan 430071China

Sleep deprivation(SD)is a widespread issue that disrupts the lives of millions of *** effects ini-tiate as changes within neurons,specifically at the DNA and RNA level,leading to disruptions in neuronal plasticity and the dysregulation of various cognitive functions,such as learning and *** acid epigenetic modifications that could regulate gene expression have been reported to play crucial roles in this ***,there is a lack of comprehensive research on the correlation of SD with nucleic acid epigenetic *** the current study,we aimed to systematically investigate the landscape of modifications in DNA as well as in small RNA molecules across multiple tissues,including the heart,liver,kidney,lung,hippocampus,and spleen,in response to chronic sleep deprivation(CSD).Using liquid chromatography-tandem mass spectrometry(LC-MS/MS)analysis,we characterized the dynamic changes in DNA and RNA modification profiles in different tissues of mice under CSD ***,we ob-served a significant decrease in the level of 5-methylcytosine(5mC)and a significant increase in the level of 5-hydroxymethylcytosine(5hmC)in the kidney in CSD *** RNA modifications,we observed an overall increased trend for most of these significantly changed modifications across six tis-sues in CSD *** study sheds light on the significance of DNA and RNA modifications as crucial epigenetic markers in the context of CSD-induced stress.

关键词： Sleep deprivation Epigenetics Mass spectrometry DNA modification RNA modification Small RNA

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Nature-inspired design of droplet-synthesized polymeric nanoelectrode for photoelectrochemical microRNA sensing within single cells

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Science Bulletin 2024年第2期69卷 159-162页

作者： Si-yuan yu Yi-Li Liu Zheng Li Dechen Jiang Jing-Juan Xu Hong-yuan Chen Wei-Wei Zhao State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Nanoelectrodes have been shown to be powerful tools for nanoscopic research on single entities,deepening the understanding of heterogeneity and stochastics for single molecules,nanoparticles and cells[1–3].However,despite their importance,current nanoelectrode preparations are highly restrained to flame/electrochemical etching,metal sputtering,electrochemical deposition,etc.[3],resulting in a limited range of materials(mainly gold,platinum and carbon)for potential-resolved detection of redox-active species(Table S1 online).The enrichment of preparation methods to introduce novel materials and mechanisms should prove significant for the development of nanoelectrodes.

关键词： electrode deepening restrained

Promoting electrocatalytic nitrogen reduction to ammonia via dopant boron on two-dimensional materials

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Rare Metals 2024年第10期43卷 5117-5125页

作者： Ya-Hui Cui Wen-Cheng Ouyang Ai-Jun Gao Chang-yuan yu Li-Peng Zhang State Key Laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical Technology College of Materials Science and Engineering Beijing University of Chemical Technology College of Life Science and Technology Beijing University of Chemical Technology

Electrocatalytic nitrogen reduction reaction(NRR) is a key process for producing energy efficient and environment friendly ammonia. Boron-doped two-dimensional materials are highly promising as NRR ***, the interaction between doped boron and matrix materials on NRR catalytic performance is still unclear,which is limiting the development of catalysts containing boron for NRR. Here, NRR on different boron-doped twodimensional(2D) materials was explored by first principle theory. It is found that adsorption energy of intermediate*NNH(E*NNH) can be used as a descriptor to characterize the catalytic activity for NRR. Boron-adsorbed black phosphorus(B-BP) is demonstrated showing excellent NRR catalytic activity and suppressing hydrogen evolution reaction. It is disclosed that the excellent catalytic performance of boron-doped structures comes from a proper quantitatively electron transfer(0.8e) between nitrogen in*NNH and the active site boron atom. This work not only established a descriptor for NRR catalytic activity on B-doped 2D materials, but also screened out a potential NRR catalyst. More importantly, the intrinsic reason and mechanism of high catalytic activity of boron-doped structures were proposed. This work provides a design principle for exploring high-performance NRR electrocatalysts containing boron.

关键词： Boron-doped two-dimensional materials Density functional theory Descriptor Electrocatalytic nitrogen reduction reaction

Coexistence of All-Order Topological States in a Three-Dimensional Phononic Topological Crystalline Insulator

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Research 2024年第2期2023卷 511-518页

作者： Hua-Shan Lai Hao Chen Chu-Hao Xia Si-yuan yu Cheng He Yan-Feng Chen National Laboratory of Solid State Microstructures&Department of Materials Science and Engineering Nanjing UniversityNanjng 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing University Nanjng 210093China Jiangsu Key Laboratory of Artificial Functional Materials Nanjing University Nanjing 210093China

Classical-wave topological materials lacking intrinsic half-integer spins are less robust while more ***,we explore a single 3-dimensional phononic topological crystalline insulator that simultaneously exhibits a whole family of first-order quadratic surface,second-order hinge,and third-order corner states within the same *** a topological crystalline insulator hosting all-order phases originates from the different topological nature when hierarchically projected onto different facets and lower dimensions,thus free from trivial cladding *** work offers an ideal platform for either robust wave propagation or localization in on-demand dimensions and may facilitate dimension division multiplexing technology.

关键词： topological dimensions crystalline

Asymptomatic low-grade appendiceal mucinous neoplasm:A case report

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World Journal of Clinical Cases 2024年第2期12卷 361-366页

作者： Min-Quan Yao yu-Peng Jiang yuan-yu Wang Yi-Ping Mou Jin-Xing Fan Department of Gastrointestinal Surgery Tongxiang First People’s HospitalJiaxing 314500Zhejiang ProvinceChina Department of General Surgery Zhejiang Provincial People’s HospitalHangzhou 310014Zhejiang ProvinceChina Endoscopy Center Tongxiang First People’s HospitalJiaxing 314500Zhejiang ProvinceChina

BACKGROUND Low-grade appendiceal neoplasms(LAMN)are characterized by low incidence and atypical clinical presentations,often leading to misdiagnosis as acute or chronic appendicitis before *** primary diagnostic tool for LAMN is abdominal computed tomography(CT)*** resection remains the cornerstone of LAMN management,necessitating en bloc tumor excision to minimize the risk of iatrogenic ***,known for its minimal invasiveness,reduced postoperative discomfort,and expedited recovery,is a safe and reliable approach for LAMN *** the possibility of pseudomyxoma peritonei development,appendectomy and partial appendectomy generally result in negative tumor margins and favorable outcomes,which can be attributed to the disease’s slow growth and lower *** SUMMARY A 71-year-old male patient was admitted to our hospital with a pelvic spaceoccupying lesion detected 1 mo *** examination showed a soft abdomen without tenderness or rebound and no palpable *** shifting dullness was noted,and digital rectal examination revealed no palpable *** revealed a raised,smooth-surfaced mass measuring 3.0 cm in the *** contrast-enhanced CT showed a markedly thickened and dilated appendix with visible cystic *** surgery was performed and revealed a significantly dilated appendix,leading to laparoscopic resection of the appendix and part of the ***-surgical pathologic analysis confirmed *** patient received symptomatic and supportive post-operative care and was discharged on postoperative day 4 without complications such as abdominal bleeding,intestinal obstruction,or incision *** tumor recurrence was observed during a 7-mo follow-up *** LAMN is a rare disease that lacks specific clinical *** CT plays a crucial role in diagnosing LAMN,and laparoscopic surgery is a safe and effective diagnostic and therapeutic approach.

关键词： Low-grade appendiceal mucinous neoplasm Pseudomyxoma peritonei Computed tomography Laparoscopy appendectomy Case report

Machine learning algorithms able to predict the prognosis of gastric cancer patients treated with immune checkpoint inhibitors

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World Journal of Gastroenterology 2024年第40期30卷 4354-4366页

作者： Hong-Wei Li Zi-yu Zhu yu-Fei Sun Chao-yu yuan Mo-Han Wang Nan Wang Ying-Wei Xue Department of Gastrointestinal Surgery Harbin Medical University Cancer HospitalHarbin 150081Heilongjiang ProvinceChina Department of Gastroenterological Surgery Harbin Medical University Cancer HospitalHarbin 150081Heilongjiang ProvinceChina Department of Anesthesia Harbin Medical University Cancer HospitalHarbin 150081Heilongjiang ProvinceChina Department of Computer Science and Technology Heilongjiang UniversityHarbin 150000Heilongjiang ProvinceChina

BACKGROUND Although immune checkpoint inhibitors(ICIs)have demonstrated significant survival benefits in some patients diagnosed with gastric cancer(GC),existing prognostic markers are not universally applicable to all patients with advanced *** To investigate biomarkers that predict prognosis in GC patients treated with ICIs and develop accurate predictive *** Data from 273 patients diagnosed with GC and distant metastasis,who un-derwent≥1 cycle(s)of ICIs therapy were included in this *** were randomly divided into training and test sets at a ratio of 7:*** set data were used to develop the machine learning models,and the test set was used to validate their predictive *** additive explanations were used to provide insights into the best *** Among the 273 patients with GC treated with ICIs in this study,112 died within 1 year,and 129 progressed within the same *** features related to overall survival and 4 related to progression-free survival were identified and used to construct eXtreme Gradient Boosting(XGBoost),logistic regression,and decision *** comprehensive evaluation,XGBoost demonstrated good accuracy in predicting overall survival and progression-free *** The XGBoost model aided in identifying patients with GC who were more likely to benefit from ICIs *** nutritional status may,to some extent,reflect prognosis.

关键词： Gastric cancer Machine learning Immune checkpoint inhibitors Web-based calculator Progression-free survival Overall survival

Basic Survey Scheduling for the Wide Field Survey Telescope(WFST)

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Research in Astronomy and Astrophysics 2024年第1期24卷 59-69页

作者： Yan-Peng Chen Ji-An Jiang Wen-Tao Luo Xian-Zhong Zheng Min Fang Chao Yang yuan-yu Hong Zong-Fei Lü Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Department of Astronomy University of Science and Technology of ChinaHefei 230026China National Astronomical Observatory of Japan National Institutes of Natural Sciences2-21-1 OsawaMitakaTokyo 181-8588Japan Institute of Deep Space Sciences Deep Space Exploration LaboratoryHefei 230026China

Aiming at improving the survey efficiency of the Wide Field Survey Telescope, we have developed a basic scheduling strategy that takes into account the telescope characteristics, observing conditions, and weather conditions at the Lenghu site. The sky area is divided into rectangular regions, referred to as “tiles,” with a size of2°. 577 × 2°. 634 slightly smaller than the focal area of the mosaic CCDs. These tiles are continuously filled in annulars parallel to the equator. The brightness of the sky background, which varies with the moon phase and distance from the moon, plays a significant role in determining the accessible survey fields. Approximately 50connected tiles are grouped into one block for observation. To optimize the survey schedule, we perform simulations by taking into account the length of exposures, data readout, telescope slewing, and all relevant observing conditions. We utilize the Greedy Algorithm for scheduling optimization. Additionally, we propose a dedicated dithering pattern to cover the gaps between CCDs and the four corners of the mosaic CCD array, which are located outside of the 3° field of view. This dithering pattern helps to achieve relatively uniform exposure maps for the final survey outputs.

关键词： telescopes surveys Moon

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