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Influence of Ca treatment on particle-microstructure relationship in heat-affected zone of shipbuilding steel with Zr-Ti deoxidation after high-heat-input welding

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Journal of Iron and Steel Research International 2022年第8期29卷 1291-1298页

作者： hong-bo liu Ju Kang Xiu-juan Zhao Cai-dong Zhang Zhang-guo Lin hong-yong Yao Zhi-qiang Tian Zhan-li liu Jie Li Chao Li Technology Research Institute HBIS GroupShijiazhuang 050023HebeiChina Beijing Key Laboratory of Pipeline Critical Technology and Equipment for Deepwater Oil and Gas Development Beijing Institute of Petrochemical TechnologyBeijing 102617China Department of Material Engineering Hebei Vocational University of Industry and TechnologyShijiazhuang 050091HebeiChina HBIS Company Limited Shijiazhuang 050023HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China HBIS Group Shisteel Company Shijiazhuang 050031HebeiChina

The effects of Ca treatment on the particle, microstructure, and toughness of heat-affected zone (HAZ) of shipbuilding steel with Zr-Ti deoxidation after high-heat-input welding were investigated. The simulated welding at a high-heat-input welding of 200 kJ/cm was carried out using Gleeble-3800 welding simulation. Then, particle characteristics were characterized using an Aztec-Feature automatic particle analysis system. Additionally, an in-situ observation experiment was performed to study the relationships between particle and microstructure by high-temperature confocal laser scanning microscopy (HT-CLSM). The results indicated that the average HAZ toughness at -40 ℃ was increased from 183 to 290 J by adding 0.0026 wt.% Ca. Meanwhile, the formation of acicular ferrite ratio was increased from 49.34% to 60.28% due to the addition of Ca. The scanning electron microscopy results clearly showed that CaO-Al_(2)O_(3)-TiOx-ZrO_(2)-MnS particles could act as effective nucleation sites for the formation of acicular ferrite, which has been verified by the observation of the particle-microstructure relationship under HT-CLSM. Furthermore, particle characterization results show that the cumulative frequency of particles with the size of 1-3 lm was 33.2% in HAZ of Zr-Ti shipbuilding steel but 66.2% in HAZ of Zr-Ti-Ca shipbuilding steel.

关键词： Shipbuilding steel Heat-affected zone Impact toughness Microstructure Particle characterization

Strong and tough chitin hydrogel constructed by dehydration and rehydration strategy

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Nano Research 2024年第9期17卷 8192-8199页

作者： Rui-Rui liu Li-bo Mao Shu-hong Yu Division of Nanomaterials and Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials and ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

As a renewable,biocompatible,biodegradable soft material,chitin hydrogels have better advantages in stability,antibacterial activity,antifouling,cost,immunogenicity,and so on than most polymer ***,compared with other widely used polymer hydrogels with high strength and toughness,the practical applications of chitin-based hydrogels have been limited by their weak mechanical properties,such as cartilage repair and meniscus ***,we present the design and fabrication of chitin hydrogels with excellent mechanical strength and toughness by a dehydration and rehydration *** sequential dehydration and rehydration processes,the crystalline domains in the chitin hydrogels can be properly *** optimized crystallinity,the elastic modulus of the chitin hydrogels exceeds all previously reported values,and the fracture toughness is even comparable to some synthetic polymer hydrogels,while maintaining a high-water-content of about 80 wt.%.At the same water content,the mechanical properties of the chitin hydrogels are positively correlated with the hydrogel crystallinity,which proves that the change of mechanical properties of hydrogels is not simply dependent on weight *** hydrogels can be further strengthened by incorporating other biopolymers that are intrinsically weak,which makes the hydrogels promising for applications in fields such as cartilage repair and meniscus ***,the hydrogels enable loading and release of water-soluble and poorly water-soluble *** highly extendable strengthening and toughening strategy of chitin and chitin-based biopolymer hydrogels paves the way for their widely applications.

关键词： chitin hydrogel crystallinity rehydration chemical transformation strong and tough

The effect of selective serotonin reuptake inhibitors on cognitive function in patients with Alzheimer’s disease and vascular dementia: focusing on fluoxetine with long follow-up periods

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Signal Transduction and Targeted Therapy 2019年第1期4卷 386-388页

作者： Yi Xie Pei-Pei liu Ya-Jun Lian hong-bo liu Jian-Sheng Kang Clinical Systems Biology Laboratories The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052 HenanChina Department of Neurology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052 HenanChina

Dear Editors,Alzheimer’s disease(AD)and vascular dementia(VaD)are two of the most common forms of dementia,resulting in increased disability and mortality,impaired quality of life,and serious burdens on society and ***,the presently available drugs can only alleviate symptoms for a short time without delaying the progression of the cognitive *** 2003,no new drugs have been approved by the US Food and Drug Administration for the treatment of *** 2019,phase III clinical trials of crenezumab and aducanumab,two anti-amyloid beta monoclonal antibodies,were *** scant progress in clinical trials urges efforts towards an alternative therapeutic strategy for dementia.

关键词： drugs Alzheimer impaired

Research on software development of air temperature prediction in coal face

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Journal of Coal Science & Engineering(China) 2011年第3期17卷 294-297页

作者： QIN Yue-ping liu hong-bo WANG Ke liu Jiang-yue State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology （Beijing） Beijing 100083 China

With ever-increasing depth of coal mine and the continuous improvement of mechanization, heat damage has become one of the major disasters in coal mine exploitation. Established the temperature prediction models suitable for different kinds of tunnels through analysis of the heat of shafts, roadways and working faces. The average annual air temperature prediction equation from the inlets of shafts to the working faces was derived. The formula was deduced using combine method of iteration and direct calculation. The method can improve the precision of air temperature prediction, so we could establish the whole pathway air temperature prediction model with high precision. Emphasizing on the effects of leakage air to air temperature of working face and using the ideology of the finite difference method and considering the differential equation of inlet and outlet at different stages, this method can significantly improve the accuracy of temperature prediction. Program development uses Visual Basic 6.0 Language, and the Origin software was used to fit the relevant data. The predicted results shows that the air temperature generally tends to rapidly increase in the air inlet, then changes slowly on working face, and finally increases sharply in air outlet in the condition of goaf air leakage. The condition is in general consistent with the air temperature change tendency of working face with U-type ventilation system. The software can provide reliable scientific basis for reasonable ventilation, cooling measures and management of coal mine thermal hazards.

关键词： finite difference method coal face air temperature prediction prediction methods

Intelligent representation method of image flatness for cold rolled strip

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Journal of Iron and Steel Research International 2024年第5期31卷 1177-1195页

作者： Yang-huan Xu Dong-cheng Wang hong-min liu bo-wei Duan National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment China National Heavy Machinery Research Institute Co.Ltd.Xi’an710018ShaanxiChina State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina

Real flatness images are the bases for flatness detection based on machine vision of cold rolled *** characteristics of a real flatness image are analyzed,and a lightweight strip location detection(SLD)model with deep semantic segmentation networks is *** interference areas in the real flatness image can be eliminated by the SLD model,and valid information can be *** this basis,the concept of image flatness is proposed for the first *** image flatness representation(IFAR)model is established on the basis of an autoencoder with a new *** optimal structure of the bottleneck layer is 16×16×4,and the IFAR model exhibits a good representation ***,interpretability analysis of the representation factors is carried out,and the difference and physical meaning of the representation factors for image flatness with different categories are *** flatness with new defect morphologies(bilateral quarter waves and large middle waves)that are not present in the original dataset are generated by modifying the representation factors of the no wave ***,the SLD and IFAR models are used to detect and represent all the real flatness images on the test *** average processing time for a single image is 11.42 ms,which is suitable for industrial *** research results provide effective methods and ideas for intelligent flatness detection technology based on machine vision.

关键词： Cold rolled strip Image flatness Location detection Representation learning bottleneck layer

Laparoscopy-assisted gastrectomy for advanced gastric cancer patients with situs inversus totalis: Two case reports and review of literature

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世界胃肠外科杂志:英文版(电子版) 2023年第9期15卷 2063-2073页

作者： hong-bo liu Xiao-Peng Cai Zhao Lu Bin Xiong Chun-Wei Peng Department of Gastrointestinal Surgery Hubei Key Laboratory of Tumor Biological Behaviors&Hubei Cancer Clinical Study CenterWuhan Peritoneal Cancer Clinical Medical CenterZhongnan Hospital of Wuhan UniversityWuhan 430070Hubei ProvinceChina School of Nursing Wuhan UniversityWuhan 430070Hubei ProvinceChina

BACKGROUND Situs inversus totalis(SIT)is a rare condition in which the positions of abdominal and thoracic organs present a“mirror image”of the normal ones in the median sagittal *** minimally invasive surgery has evolved to achieve laparoscopic gastrectomy for gastric cancer(GC)patients with SIT,it is difficult to perform lymphadenectomy(LND)in such a transposed anatomical ***,we report the cases of two patients with SIT who successfully underwent laparoscopy-assisted gastrectomy(LAG)with D2 *** SUMMARY Case 1:A 65-year-old man was admitted for intermittent abdominal pain and distension,occasional belching,and acid reflux for 4 *** was diagnosed with GC(cT3N1-2M0)with *** surgery,he had undergone four cycles of neoadjuvant chemotherapy and ***,the patient was evaluated as having a partial response,and laparoscopy-assisted distal gastrectomy with D2 LND and Billroth II reconstruction were *** operation was performed successfully within 240 min with an estimated blood loss of 50 mL and no severe *** patient was discharged on postoperative day(POD)*** 2:A 55-year-old man was admitted for upper abdominal distension with pain and discomfort after eating for 3 *** was diagnosed with GC(cT3N1M0)with *** had a history of hypertension for more than 10 years;however,his blood pressure was well-controlled via regular *** performed laparoscopy-assisted total gastrectomy with D2 LND and Roux-en-Y *** operation was performed successfully within 168 min with an estimated blood loss of 50 mL and no severe *** patient was discharged on POD *** LAG with D2 LND could be considered an accessible,safe,and curative procedure for advanced GC patients with SIT.

关键词： Situs inversus totalis Laparoscopy-assisted gastrectomy Advanced gastric cancer Surgery modality Lymphadenectomy Case report

An Approximation Algorithm for the Parallel-Machine Customer Order Scheduling with Delivery Time and Submodular Rejection Penalties

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Journal of the Operations Research Society of China 2024年第2期12卷 495-504页

作者： hong-Ye Zheng Suo-Gang Gao Wen liu bo Hou School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024HebeiChina

In this paper,we consider the parallel-machine customer order scheduling with delivery time and submodular rejection *** this problem,we are given m dedicated machines in parallel and n customer *** order has a delivery time and consists of m product types and each product type should be manufactured on a dedicated *** order is either rejected,in which case a rejection penalty has to be paid,or accepted and manufactured on the m dedicated *** objective is to find a solution to minimize the sum of the maximum delivery completion time of the accepted orders and the penalty of the rejected orders which is determined by a submodular *** design an LP rounding algorithm with approximation ratio of n+1 for this problem.

关键词： Order scheduling Delivery time Submodular rejection penalty Approximation algorithm

Persistent SARS-CoV-2 infection in asymptomatic young adults

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Signal Transduction and Targeted Therapy 2022年第4期7卷 961-963页

作者： Mai-Juan Ma Shao-Fu Qiu Xiao-Ming Cui Ming Ni hong-Jie liu Run-Ze Ye Lin Yao hong-bo liu Wu-Chun Cao hong-Bin Song State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyBeijingChina Center for Disease Control and Prevention Chinese People’s Liberation ArmyBeijingChina Beijing Institute of Radiation Medicine BeijingChina School of Public Health Shandong UniversityJinanChina

Dear Editor,While most of the patients infected with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)cleared the virus within a few weeks of infection,some people have a persistent infection or persistent shedding viral RNA in the long *** persistent detection of viral RNA in clinical specimens is unlikely to reflect either relapse or reinfection in most cases because the replication-competent virus is generally not recoverable after ten days following symptom onset in mild to moderate cases of COVID-191 and after 20 days in severe or immunocompromised cases.

关键词： infection acute respiratory

Parameter estimation in exponential models by linear and nonlinear fitting methods

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Frontiers of Information Technology & Electronic Engineering 2017年第3期18卷 434-444页

作者： Ping YANG Chao-peng WU Yi-lu GUO hong-bo liu Hui HUANG Hang-zhou WANG Shu-yue ZHAN Bang-yi TAO Quan-quan MU Qiang WANG hong SONG School of Digital Media & Design Hangzhou Dianzi University Ocean College Zhejiang University State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic Administration State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences

Estimation of unknown parameters in exponential models by linear and nonlinear fitting methods is discussed. Based on the extreme value theorem and Taylor series expansion, it is proved theoretically that the parameters estimated by the linear fitting method alone cannot minimize the sum of the squared residual errors in the measurement data when measurement noise is involved in the data. Numerical simulation is performed to compare the performance of the linear and nonlinear fitting methods. Simulation results show that the linear method can obtain only a suboptimal estimate of the unknown parameters and that the nonlinear method gives more accurate results. Application of the fitting methods is demonstrated where the water spectral attenuation coefficient is estimated from underwater images and imaging distances, which supports the improvement in the accuracy of parameter estimation by the nonlinear fitting method.

关键词： Exponential model Parameter estimation Linear least squares Nonlinear fitting