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Effect of rare earth on primary carbides in H13 die steel and their addition method:a review

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Journal of Iron and Steel Research International 2024年第3期31卷 531-551页

作者： jing-feng Wang Lin-zhu Wang chao-yi chen xiang Wang Fei zhao School of Materials and Metallurgy Guizhou UniversityGuiyang 550025GuizhouChina zhengzhou Railway Vocational and Technical College Zhengzhou 450000HenanChina Guizhou Provincial University Key Laboratory of High Performance Battery Materials Guizhou UniversityGuiyang 550025GuizhouChina Shougang Guiyang Special Steel Co. Guiyang 550005GuizhouChina

Larger-sized primary carbides lead to stress concentration during the application of H13 hot-work die steel,resulting in microcracks and fatigue *** earth was usually added to modify the carbides and *** existing literature is reviewed on the effect of rare earth on primary carbides in H13 steel.A comprehensive review on the effect of rare earth on the characteristics of primary carbides,i.e.,number,size,morphology,and thermal stability in H13 steel,was *** precipitation mechanism and nucleation of primary carbides with rare earth were *** position and form of rare earth in steel and their effects on alloying elements segregation were *** addition techniques of rare earth in H13 steel were compared,and the prospects for other uncommon rare earth and emerging technology were *** on the current references,it can be known that adding rare earth facilitated refined and dispersed primary *** size of primary carbides would be reduced,and their morphology would be improved because the rare earth inclusions formed in H13 steel can act as nucleation cores forγ-Fe orδ-Fe,refining the dendritic ***,the number of primary carbides at grain boundaries would be significantly ***,rare earth had little impact on thermal *** nucleation of primary carbides tended to be inhibited due to the modification of inclusions by rare earth which were likely to be nucleation cores for primary *** earth had been reported to affect the mechanism and process of primary carbide ***,the addition of rare earth can inhibit the segregation of alloying elements and carbon diffusion by ***,laboratory experiments and theoretical calcu-lations need to be conducted to study the states and evolution of rare earth steels.

关键词： Rare earth H13 die steel Primary carbide Nucleation Dendritic structure

Interfacial Electronic Modulation of Dual-Monodispersed Pt–Ni_(3)S_(2) as Efficacious Bi-Functional Electrocatalysts for Concurrent H_(2) Evolution and Methanol Selective Oxidation

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Nano-Micro Letters 2024年第4期16卷 415-431页

作者： Qianqian zhao Bin zhao Xin Long Renfei Feng Mohsen Shakouri Alisa Paterson Qunfeng Xiao yu Zhang xian‑Zhu Fu jing‑Li Luo Shenzhen Key Laboratory of Energy Electrocatalytic Materials Shenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China Canadian Light Source Inc. SaskatoonSK S7N 0X4Canada Instrumental Analysis Center of Shenzhen University(Lihu Campus) Shenzhen UniversityShenzhen 518055People’s Republic of China

Constructing the efficacious and applicable bifunctional electrocatalysts and establishing out the mechanisms of organic electro-oxidation by replacing anodic oxygen evolution reaction(OER) are critical to the development of electrochemicallydriven technologies for efficient hydrogen production and avoid CO_(2) emission. Herein, the hetero-nanocrystals between monodispersed Pt(~ 2 nm) and Ni_(3)S_(2)(~ 9.6 nm) are constructed as active electrocatalysts through interfacial electronic modulation, which exhibit superior bi-functional activities for methanol selective oxidation and H_(2) generation. The experimental and theoretical studies reveal that the asymmetrical charge distribution at Pt–Ni_(3)S_(2) could be modulated by the electronic interaction at the interface of dual-monodispersed heterojunctions, which thus promote the adsorption/desorption of the chemical intermediates at the interface. As a result, the selective conversion from CH_(3)OH to formate is accomplished at very low potentials(1.45 V) to attain 100 m A cm^(-2) with high electronic utilization rate(~ 98%) and without CO_(2) emission. Meanwhile, the Pt–Ni_(3)S_(2) can simultaneously exhibit a broad potential window with outstanding stability and large current densities for hydrogen evolution reaction(HER) at the cathode. Further, the excellent bi-functional performance is also indicated in the coupled methanol oxidation reaction(MOR)//HER reactor by only requiring a cell voltage of 1.60 V to achieve a current density of 50 m A cm^(-2) with good reusability.

关键词： Dual-monodispersed heterostructure Electronic interactive modulation Reaction mechanism Methanol oxidation reaction Hydrogen generation

Engineered extracellular vesicles: A new approach for targeted therapy of tumors and overcoming drug resistance

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Cancer Communications 2024年第2期44卷 205-225页

作者： chen Ming-Kun chen Zi-xian Cai Mao-Ping chen Hong chen Zhuang-Fei zhao Shan-chao Department of Urology The Third Affiliated Hospital of Southern Medical UniversityGuangzhouGuangdongP.R.China The Third Clinical College Southern Medical UniversityGuangzhouGuangdongP.R.China Luoyang Key Laboratory of Organic Functional Molecules College of Food and DrugLuoyang Normal UniversityLuoyangHenanP.R.China Department of Urology Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdongP.R.China

Targeted delivery of anti-tumor drugs and overcoming drug resistance in malig-nant tumor cells remain significant clinical ***,there are only few effective methods to address these *** vesicles(EVs),actively secreted by cells,play a crucial role in intercellular information transmis-sion and cargo *** studies have demonstrated that engineered EVs can serve as drug delivery carriers and showed promising application ***,there is an urgent need for further improvements in the isolation and purification of EVs,surface modification techniques,drug assem-bly processes,and precise recognition of tumor cells for targeted drug delivery *** this review,we summarize the applications of engineered EVs in cancer treatment and overcoming drug resistance,and current challenges asso-ciated with engineered EVs are also *** review aims to provide new insights and potential directions for utilizing engineered EVs as targeted delivery systems for anti-tumor drugs and overcoming drug resistance in the near future.

关键词： drug delivery drug resistance extracellular vesicles nanoparticles

Syntheses and properties of associative acrylamide copolymers containing short hydrophobic chains used in a friction reducer for slick-water fracturing

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Petroleum Science 2024年第3期21卷 1889-1901页

作者： Ya-Xing Dai xian-Li Zhang Si-yuan Liu Feng-Run-Ze Zhang Yi-Xi Zhang yu-Tong Sang jing-Xi zheng zhao-Sheng Liu Peng Zhang College of Chemistry and Chemical Engineering Chongqing University of Science and TechnologyChongqing401331China College of Ecology and Environment Chongqing Resources and Environmental Protection of UniversityChongqing401331China China China Property Project Department of Dezhou Mining Property Service CenterShengli Oilfield Company of SinopecDezhou253000ShandongChina

Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacrylamide *** new drag reducers were synthesized from acrylamide(AM),sodium acrylate(Na AA)and a cationic modified monomer(AQAS1 or AQAS2)via aqueous solution polymerization,and the copolymers were named P(AM/Na AA/AQAS1)and P(AM/Na AA/AQAS2),*** structures of the drag reduction agents were confirmed by IR and1H NMR *** molecular weight(Mw)of P(AM/Na AA/AQAS1)was 1.79×10^(6)g/*** the copolymer concentration was 1000 mg/L and the flow rate was 45 L/min,in fresh water the highest drag reduction rate was 75.8%,in 10,000 mg/L Na Cl solution the drag reduction rate decreased to 72.9%.The molecular weight of P(AM/Na AA/AQAS2)was 3.17×10^(6)g/*** the copolymer concentration was500 mg/L and the flow rate was 45 L/min,the drag reduction rate reached 75.2%,and in 10,000 mg/L Na Cl solution the drag reduction rate was 73.3%,decreased by approximately 1.9%.The drag reduction rate for partially hydrolyzed polyacrylamide(HPAM)was also investigated,and the results showed that the drag reduction rates for 500 and 1000 mg/L HPAM solutions were merely 43.2%and 49.0%in brine,*** with HPAM,both of the above copolymers presented better drag reduction capacities.

关键词： Shale gas Slick water Drag reducer Modified monomer Copolymerization

SARS-CoV-2 immunity in animal models

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Cellular & Molecular Immunology 2024年第2期21卷 119-133页

作者： zhao chen Yaochang yuan Qingtao Hu Airu Zhu Fenghua chen Shu Li Xin Guan chao Lv Tian Tang Yiyun He Jinling cheng Jie zheng Xiaoyu Hu jingxian zhao Jincun zhao jing Sun State Key Laboratory of Respiratory Disease National Clinical Research Centre for Respiratory DiseaseNational Centre for Respiratory MedicineGuangzhou Institute of Respiratory Healththe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong 510182China GMU-GIBH Joint School of Life Sciences Guangzhou Medical UniversityGuangzhou 510000China Guangzhou National Laboratory GuangzhouGuangdong 510005China Shanghai Institute for Advanced Immunochemical Studies School of Life Science and TechnologyShanghaiTech UniversityShanghai 201210China Institute for Hepatology National Clinical Research Center for Infectious DiseaseShenzhen Third People’s Hospitalthe Second Affiliated HospitalSchool of MedicineSouthern University of Science and TechnologyShenzhen 518005China

The COVID-19 pandemic,which was caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has become a worldwide health crisis due to its ***-CoV-2 infection results in severe respiratory illness and can lead to significant complications in affected *** complications encompass symptoms such as coughing,respiratory distress,fever,infectious shock,acute respiratory distress syndrome(ARDS),and even multiple-organ *** models serve as crucial tools for investigating pathogenic mechanisms,immune responses,immune escape mechanisms,antiviral drug development,and vaccines against ***,various animal models for SARS-CoV-2 infection,such as nonhuman primates(NHPs),ferrets,hamsters,and many different mouse models,have been *** model possesses distinctive features and *** this review,we elucidate the immune response elicited by SARS-CoV-2 infection in patients and provide an overview of the characteristics of various animal models mainly used for SARS-CoV-2 infection,as well as the corresponding immune responses and applications of these models.A comparative analysis of transcriptomic alterations in the lungs from different animal models revealed that the K18-hACE2 and mouse-adapted virus mouse models exhibited the highest similarity with the deceased COVID-19 ***,we highlighted the current gaps in related research between animal model studies and clinical investigations,underscoring lingering scientific questions that demand further clarification.

关键词： COVID-19 SARS-CoV-2 animal models immune response

Impacts of inter-satellite links on the ECOM model performance for BDS-3 MEO satellites

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Satellite Navigation 2024年第1期5卷 140-154页

作者： chao Yang jing Guo Xiaolong Xu Longyu Wang Qile zhao GNSS Research Center Wuhan UniversityNo.129 Luoyu RoadWuhan430079China

Inter-satellite link(ISL)plays an essential role in current and future Global Navigation Satellite System(GNSS).In this study,we investigate the impact of ISL observations on precise orbit determination for BeiDou-3 Navigation Satellite System(BDS-3)Medium Earth Orbit(MEO)satellites based on different Extended CODE Orbit Models(ECOM).Thanks to the better observation geometry of the Ka-band ISL data compared to the L-band data for BDS-3 MEO satellites,the ISL solution substantially reduces Orbit Boundary Discontinuity(OBD)errors,except for C30,which suffers from unstable Ka-band hardware *** the external quality analysis,ISL significantly enhances the reliability of the orbit of MEO satellites manufactured by the China Academy of Space Technology(CAST).The standard deviation(STD)of the satellite laser ranging(SLR)residuals is approximately 2.5 cm,and the root mean square(RMS)is reduced by 10–23%compared to L-band ***,the Sun-elongation angle dependent systematic error in SLR residuals nearly vanishes based on the reduced 5-parameter ECOM(ECOM1)or extended 7-parameter ECOM(ECOM2)with ISL *** is because the ISL reduces the correlation between state parameters and solar radiation pressure(SRP)parameters as well as those among SRP parameters,leading to a more accurate estimation of both orbit and SRP perturbations,particularly those along B *** confirms that the deficiency of the SRP models for BDS-3 CAST satellites can be compensated by using better observation geometry from ISL *** the other hand,for the satellite manufactured by Shanghai Engineering Center for Microsatellites(SECM),the ISL allows for a more accurate estimation of the Bc_(1)parameter in the ECOM1 *** only reduces linear systematic error,possibly because the impact generated by the satellite bus cannot be entirely absorbed by the B-direction parameters.

关键词： BDS-3 MEO Inter-satellite link Solar radiation pressure ECOM

In Situ Raman Monitoring of Trace Antibiotics in Different Harsh Water Environments

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Energy & Environmental Materials 2024年第1期7卷 284-293页

作者： Chundong Liu Fengcai Lei Maogang Gong Xiaoming Zhou Xiaofei zhao Zhen Li chao Zhang baoyuan Man jing yu School of Physics and Electronics Institute of Materials and Clean EnergyShandong Normal UniversityJinan 250014China College of Chemistry Chemical Engineering and Materials ScienceInstitute of Biomedical SciencesShandong Normal UniversityJinan 250014China Department of Physics and Astronomy University of KansasLawrenceKansas 66045USA Shandong Provincial Hospital Shandong First Medical UniversityJinan 250021China

In situ surface-enhanced Raman scattering(SERS)is a widely used operando analytical technique,while facing numerous complex factors in applications under aqueous environment,such as low detection sensitivity,poor anti-interference capability,etc.,resulting in unreliable *** address these issues,herein a new hydrophobic SERS strategy has been *** comprehensively designing and researching a SERS-active structure of superhydrophobic ZnO/Ag nanowires,we demonstrate that hydrophobicity can not only draw analytes from water onto substrate,but also adjust"hottest spot"from the bottom of the nanowires to the *** a result,the structure can simultaneously concentrate the dispersed molecules in water and the enhanced electric field in structure into a same zone,while perfecting its own anti-interference *** underwater in situ analytical enhancement factor of this platform is as high as 1.67×10^(11),and the operando limited of detection for metronidazole(MNZ)reaches to 10^(-9)*** importantly,we also successfully generalized this structure to various real in situ detection scenarios,including on-site detection of MNZ in corrosive urine,real-time warning of wrong dose of MNZ during intravenous therapy,in situ monitoring of MNZ in flowing wastewater with particulate interference,etc.,demonstrating the great application potential of this hydrophobic *** work realizes a synergistic promotion for in situ SERS performance under aqueous environment,and also provides a novel view for improving other in situ analytical techniques.

关键词： antibiotic detection hydrophobic structure In situ Raman metronidazole wettability

Comprehensive evaluation of rare case:From diagnosis to treatment of a sigmoid Schwannoma:A case report

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 244-250页

作者： jing-Yi Li Xi-Zhuang Gao Jian Zhang xiang-zheng Meng Yi-xian Cao Kun zhao Clinical Medical College of Jining Medical University Jining Medical UniversityJining 272000Shandong ProvinceChina Department of Gastroenterology The First People's Hospital of JiningJining 272000Shandong ProvinceChina

BACKGROUND Schwannomas are uncommon tumors originating from Schwann cells,forming the neural *** account for approximately 2%-6%of all mesenchymal tumors and are most commonly identified in peripheral nerve trunks,with rarity in the gastrointestinal *** gastrointestinal locations,the stomach harbors the majority of nerve sheath tumors,while such occurrences in the sigmoid colon are exceptionally *** SUMMARY This study presented a clinical case involving a 60-year-old female patient who,during colonoscopy,was diagnosed with a submucosal lesion that was later identified as a nerve sheath *** patient underwent surgical resection,and the diagnosis was confirmed through *** study highlighted an exceptionally uncommon occurrence of a nerve sheath tumor in the sigmoid colon,which was effectively managed within our ***,a comprehensive review of relevant studies was *** The preoperative diagnosis of nerve sheath tumors poses challenges,as the definitive diagnosis still relies on pathology and *** categorized as benign,these tumors have the potential to demonstrate malignant ***,the optimal treatment approach entails the complete surgical excision of the tumor,ensuring the absence of residual lesions at the margins.

关键词： Schwannoma Gastrointestinal stromal tumors Treatment Sigmoid colon Case report

A novel route to enhance high-temperature mechanical property and thermal shock resistance of low-carbon Mgo-C bricks by introducing ZrSiO_(4)

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Journal of Iron and Steel Research International 2024年第6期31卷 1436-1448页

作者： Chun-hui Sun Ling-ling Zhu Hao Yan Wei zhao jing-xuan Liu Lin Ren xian-tang zhao Xiao-song Tong Shu-wen yu Beijing Lirr High-Temperature Materials Co. Ltd.Beijing 102211China School of Materials Science and Engineering Henan Province Industrial Technology Research Institute of Resources and MaterialsZhengzhou UniversityZhengzhou 450001HenanChina School of Chemistry and Chemical Engineering Suzhou UniversitySuzhou 234000AnhuiChina

Conventional MgO-C bricks(graphite content>14 wt.%)produce a great deal of greenhouse gas emission,while low-carbon MgO-C bricks have serious thermal shock resistance during high-temperature *** enhance the high-temperature mechanical property and thermal shock resistance of low-carbon MgO-C bricks,a novel route of introducing ZrSiO_(4) powder into low-carbon MgO-C bricks was reported in such refractories with 2 wt.% flaky *** results indicate that the low-carbon MgO-C brick with 0.5 wt.%ZrSiO_(4) addition has the maximum hot modulus of rupture at 1400℃ and the corresponding specimen fired in the carbon embedded atmosphere has the maximum residual strength ratio(98.6%)after three thermal shock *** is found that some needle-like AlON and plate-like Al_(2)O_(3)-ZrO_(2) composites were in situ formed in the matrices after the low-carbon MgO-C bricks were coked at 1400℃,which can enhance the high-temperature mechanical property and thermal shock resistance due to the effect of fiber toughening and particle ***,CO_(2) emission of the newly developed low-carbon MgO-C bricks is reduced by 58.3% per ton steel after using them as the working lining of a 90 t vacuum oxygen decarburization ladle.

关键词： Low-carbon MgO-C brick ZrsiO_(4) Synergistic toughening effect High-temperature mechanical property Thermal shock resistance Vacuum oxygen decarburization ladle