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High-tenacity in-situ Ti/Zr-based bulk metallic glasses composites fabricated by industrial high-pressure die casting

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Journal of Materials Science & Technology 2024年第3期170卷 177-185页

作者： Yang Li Wenbo luo Ying Jin Zhiyong Xue Guiqing Wang Yanan Ren Haoxin Li Haibo ke Baoan Sun Weihua Wang Institute for Advanced Materials North China Electric Power UniversityBeijing 102206China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China

The glass-forming ability and mechanical properties of metallic glasses and their composites are well known to be sensitive to the preparation conditions and are highly deteriorated by industrial preparing conditions such as low-purity raw materials and low ***,we showed that a series of in-situ bulk metallic glass composites(BMGCs)which exhibit excellent ductility and segmental work hardening were successfully developed utilizing a high vacuum high-pressure die casting(HV-HPDC)technology along with industrial-grade raw *** tensile properties of these BMGCs are systematically investigated and correlated with the alloy *** compared with the copper mold suction casting method,the volume fraction difference of the dendrite phase for the BMGCs with the same composition is not significant when fabricated by the HV-HPDC,whereas the size of theβ-phase is generally *** BMGCs with the composition of Ti_(48)Zr_(20)(V_(12/17)Cu_(5/17))19 Be 13 obtained by the HV-HPDC process show ductility up to 11.3%under tension at room temperature and exhibit a certain amount of work *** conditions need to be met to enable the BMGCs,which are prepared by vacuum die-casting to retain favorable ductility:(1)The volume fraction ofβphase stays below 62%±2%;(2)The equiaxed crystals with a more uniform size in the range of 5-10μ***,the results of the present study provided guidance for developing BMGCs with good ductile properties under industrial conditions.

关键词： Vacuum die casting Bulk metallic glass composites Mechanical properties β-phase

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27-Hydroxycholesterol/liver X receptor/apolipoprotein E mediates zearalenone-induced intestinal immunosuppression:A key target potentially linking zearalenone and cancer

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Journal of Pharmaceutical Analysis 2024年第3期14卷 371-388页

作者： Haonan Ruan Jing Zhang Yunyun Wang Ying Huang Jiashuo Wu Chunjiao He Tongwei ke Jiaoyang luo Meihua Yang key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of EducationInstitute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing100193China

Zearalenone(ZEN)is a mycotoxin that extensively contaminates food and feed,posing a significant threat to public ***,the mechanisms behind ZEN-induced intestinal immunotoxicity remain *** this study,Sprague-Dawley(SD)rats were exposed to ZEN at a dosage of 5 mg/kg/day *** a duration of 14 *** results demonstrated that ZEN exposure led to notable pathological alterations and immunosuppression within the ***,ZEN exposure caused a significant reduction in the levels of apolipoprotein E(ApoE)and liver X receptor(LXR)(Pkers(P<0.05)and decreased the presence of 27-hydroxycholesterol(27-HC)in the intestine(P<0.05).It was observed that ApoE or LXR agonists were able to mitigate the immunosuppressive effects induced by ***,a bioinformatics analysis highlighted that the downregulation of ApoE might elevate the susceptibility to colorectal,breast,and lung *** findings underscore the crucial role of the 27-HC/LXR/ApoE axis disruption in ZEN-induced MDSCs proliferation and subsequent inhibition of T lymphocyte activation within the rat ***,ApoE may emerge as a pivotal target linking ZEN exposure to cancer development.

关键词： Zearalenone Intestinal immunosuppression Apolipoprotein E Bioinformatics analysis Cancer

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Strong Antiferromagnetic Exchange-Coupling Observed in Hydride-Bridged Dimeric Dysprosium(Ⅲ)Single-Molecule Magnet

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Chinese Journal of Chemistry 2024年第4期42卷 391-396页

作者： Qian-Cheng luo ke-Xin Yu Peng-Bo Jin Ye-Ye Liu Yuan-Qi Zhai Yan-Zhen Zheng Frontier Institute of Science and Technology State Key Laboratory of Electrical Insulation and Power EquipmentXi'an Key Laboratory of Electronic Devices and Materials ChemistrySchool of Chemistry and School of PhysicsXi'an Jiaotong University99 Yanxiang RoadXi'anShaanxi710054 China

One dihydride-bridged dimeric Dy(Ⅲ)guanidinate complex,formulated as[{(Me_(3)Si)_(2)NC(NiPr)_(2)}_(2)Dy(μ-H)]_(2)(1Dy),was successfully isolated and the introduction of hydride bridges significantly reduces the intramolecular Dy(Ⅲ)…Dy(Ⅲ)distance to only 3.688(1)Å.To investigate the effect of such a short Dy(Ⅲ)…Dy(Ⅲ)distance on magnetism,we also prepared its dibromide-bridged analogue[{(Me_(3)Si)_(2)NC(NiPr)_(2)}_(2)Dy(μ-Br)]_(2)(2Dy),which has a much longer Dy(Ⅲ)…Dy(Ⅲ)distance of 4.605(4)Å.Surprisingly,2Dy demonstrates much larger effective energy barrier for magnetization reversal(U_(eff))and higher blocking temperature(T_(B)).The worse performance of 1Dy is attributed to the concerted effect of strong antiferromagnetic interactions between Dy(Ⅲ)ions(J_(total)=–2.683 cm^(–1))and the unparallel arrangement of magnetic principle axes of the Dy(Ⅲ)ions for 1Dy.

关键词： Single-molecule magnets Lanthanides Guanidinate ligand Hydride bridge Magnetic properties Ab initio calculations

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A highly sensitive fluorescent probe RN-NA reveals peroxynitrite as a novel biomarker for primary open angle glaucoma

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 219-227页

作者： Bo Qin Yuan Lei luo Bao You-Jia Zhang ke-Yin Liu Yu-Hong Chen Department of Ophthalmology&Visual Science Eye&ENT HospitalShanghai Medical CollegeFudan UniversityShanghai 200031China key Laboratory of Myopia NHFPC(Fudan University)Shanghai Key Laboratory of Visual Impairment and Restoration(Fudan University)Shanghai 200031China State key Laboratory of Biobased Material and Green Papermaking Key Laboratory of Pulp&Paper Science and Technology of Shandong Province/Ministry of EducationQilu University of TechnologyShandong Academy of SciencesJinan 250353Shandong ProvinceChina

AIM:To directly quantify peroxynitrite(ONOO-)using a highly sensitive fluorescence resonance energy transfer probe RN-NA,investigate the association between ONOOand primary open angle glaucoma(POAG),and clarify whether RN-NA could be used as a potential tool for POAG ***:Plasma and aqueous humor(AH)samples were collected from POAG patients(n=100,age:59.70±6.87y)and age-related cataract(ARC)patients(n=100,age:61.15±4.60y)admitted to our ***,RN-NA was used to detect ONOO-in plasma and AH samples,and the relationship between ONOO-level and POAG was analyzed using binary logistic ***,Pearson correlation analysis was applied to characterize the correlation of the levels of ONOO-with the patients’age,intraocular pressure(IOP),and mean deviation of visual field *** ONOO-scavenger MnTMPyP was employed to treat the 3-morpholinosyndnomine(SIN-1)-induced ocular hypertension in mice(n=7,6-8wk).Finally,the IOP and ONOO-in both eyes were measured 30min after the last drug ***:ONOO-levels of AH and plasma were significantly higher in the POAG group than in the ARC group(Pker of POAG,especially advanced ***,anti-nitration compounds may be novel ocular hypotens

关键词： peroxynitrite fluorescent probe RN-NA primary open angle glaucoma 3-morpholinosyndnomine

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Prediction of soil organic carbon stock combining Sentinel-1 and Sentinel-2 images in the Zoige Plateau, the northeastern Qinghai-Tibet Plateau

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Ecological Processes 2024年第2期13卷 165-176页

作者： Junjie Lei Changli Zeng Lv Zhang Xiaogang Wang Chanhua Ma Tao Zhou Benjamin Laffitte ke luo Zhihan Yang Xiaolu Tang State key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Sichuan Academy of Geological Survey Sichuan Institute of Nuclear Geological Survey College of Earth Sciences Chengdu University of Technology Tianfu Yongxing Laboratory

Background Soil organic carbon（SOC） is a critical component of the global carbon cycle, and an accurate estimate of regional SOC stock（SOCS） would significantly improve our understanding of SOC sequestration and cycles. Zoige Plateau, locating in the northeastern Qinghai-Tibet Plateau, has the largest alpine marsh wetland worldwide and exhibits a high sensitivity to climate fluctuations. Despite an increasing use of optical remote sensing in predicting regional SOCS, optical remote sensing has obvious limitations in the Zoige Plateau due to highly cloudy weather, and knowledge of on the spatial patterns of SOCS is limited. Therefore, in the current study, the spatial distributions of SOCS within 100 cm were predicted using an XGBoost model—a machine learning approach, by integrating Sentinel-1, Sentinel-2 and field observations in the Zoige *** The results showed that SOC content exhibited vertical distribution patterns within 100 cm, with the highest SOC content in topsoil. The tenfold cross-validation approach showed that XGBoost model satisfactorily predicted the spatial patterns of SOCS with a model efficiency of 0.59 and a root mean standard error of 95.2 Mg ha-1. Predicted SOCS showed a distinct spatial heterogeneity in the Zoige Plateau, with an average of 355.7 ± 123.1 Mg ha-1within 100 cm and totaled 0.27 × 10～9 Mg *** High SOC content in topsoil highlights the high risks of significant carbon loss from topsoil due to human activities in the Zoige Plateau. Combining Sentinel-1 and Sentinel-2 satisfactorily predicted SOCS using the XGBoost model, which demonstrates the importance of selecting modeling approaches and satellite images to improve efficiency in predicting SOCS distribution at a fine spatial resolution of 10 m. Furthermore, the study emphasizes the potential of radar（Sentinel-1） in developing SOCS mapping, with the newly developed fine-resolution mapping having important applications in land management, ecological resto

关键词： SOC Vegetation index Texture XGBoost Sentinel-1 Sentinel-2

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Unveiling factuality and injecting knowledge for LLMs via reinforcement learning and data proportion

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Science China(Information Sciences) 2024年第10期67卷 389-390页

作者： Wenjun ke Ziyu SHANG Zhizhao luo Peng WANG Yikai GUO Qi LIU Yuxuan CHEN School of Computer Science and Engineering Southeast University key Laboratory of New Generation Artificial Intelligence Technology and Its Interdisciplinary Applications(Southeast University) Beijing Institute of Technology Zhuhai Beijing Institute of Computer Technology and Application

Large language models(LLMs) have demonstrated remarkable effectiveness across various natural language processing(NLP) tasks, as evidenced by recent studies [1, 2]. However, these models often produce responses that conflict with reality due to the unreliable distribution of facts within their training data, which is particularly critical for applications requiring high credibility and accuracy [3].

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Evaluation of the injection and plugging ability of a novel epoxy resin in cement cracks

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Petroleum Science 2024年第2期21卷 1211-1220页

作者： Guang-Yao Leng Wei Yan Hai-Mu Ye Er-Dong Yao Ji-Bin Duan Zheng-xian Xu ke-Pei Li Jing-Ru Zhang Zhong Li State key Laboratory of Petroleum Resource&Prospecting China University of Petroleum(Beijing)Beijing102249China CNPC Liaohe Oilfield Gas Storage Co.LTD Panjin124000LiaoningChina CNOOC Research Institute Co. Ltd.Beijing100028China

Sustained casing pressure(SCP)is a crucial issue in the oil and gas production *** resins,exhibiting exceptional compressive strength,ductility,and shear bonding strength,have the potential to form reliable *** injectivity and sealing capacity of the epoxy resin is crucial parameters for the success of shallow remediation *** study aimed to develop and assess a novel solid-free resin sealant as an alternative to Portland cement for mitigating fluid *** investigation evaluated the viscosity,compressive strength,and brittleness index of the epoxy resin sealant,as well as its tangential and normal shear strengths in conjunction with casing *** flow characteristics and sealing abilities of conventional cement and epoxy resin were comparatively analyzed in *** results showed that the application of a viscosity reducer facilitated control over the curing time of the epoxy resin,ranging from 1.5 to 6 h,and reduced the initial viscosity from 865.53 to 118.71 m Pa,*** mechanical properties of the epoxy resin initially increased with a rise in curing agent content before experiencing a minor *** epoxy resin containing 30%curing agent exhibited optimal mechanical *** a 14-day curing period,the epoxy resin's compressive strength reached81.37 MPa,2.12 times higher than that of cement,whereas the elastic modulus of cement was 2.99 times greater than that of the epoxy *** brittleness index of epoxy resin is only 3.42,demonstrating high flexibility and *** tangential and normal shear strengths of the epoxy resin exceeded those of cement by 3.17 and 2.82 times,*** a 0.5 mm-wide crack,the injection pressure of the epoxy resin remained below 0.075 MPa,indicating superior injection and flow ***,the injection pressure of cement surged dramatically to 2.61 MPa within 5 *** breakthrough pressure of0.5 PV epoxy resin reached 7.53 MPa,decreasing the crack's perme

关键词： Sustained casing pressure Epoxy resin sealant Curing agent Viscosity reducer Mechanical properties Crack sealing

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Wide Stopband Substrate Integrated Waveguide Filter Using Bisection and Trisection Coupling in Multilayer

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Chinese Journal of Electronics 2024年第2期33卷 436-442页

作者： Peng CHU Jianguo FENG Peng ZHU Lei GUO Long ZHANG Leilei LIU Guoqing luo ke WU College of Electronic and Optical Engineering Nanjing University of Posts and Telecommunications National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology School of Information and Communication Engineering Dalian University of Technology Guangdong Provincial key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen University College of Electronics and Information Engineering Shenzhen University School of Electronics and Information Hangzhou Dianzi University Poly-Grames Research Center Polytechnique Montreal

This article presents a highly efficient method for substrate-integrated-waveguide（SIW） filters to achieve very wide stopbands. By employing the proposed trisection slots in addition to the bisection slots as the inter-coupling structures, all spurious modes below TE505 of a SIW filter working in the fundamental mode TE101（f0）can be eliminated without requiring additional structure or complex theoretical analysis, without affecting the design of the fundamental passbands, and without degrading the performance of the filters. For verification, two prototype filters are designed, fabricated, and measured with wide stopbands up to 4.15f0 and 4.83f0, respectively. The proposed technique could facilitate the development of high-performance wide-stopband SIW filters for microwave/wireless circuits and systems.

关键词： Microwave measurement Couplings Filters Prototypes Nonhomogeneous media Microwave theory and techniques Microwave circuits

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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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Pollutant emissions from biomass burning:A review on emission characteristics,environmental impacts,and research perspectives

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Particuology 2024年第2期85卷 296-309页

作者： ke Jiang Ran Xing Zhihan luo Wenxuan Huang Fan Yi Yatai Men Nan Zhao Zhaofeng Chang jinfeng Zhao Bo Pan Guofeng shen College of Urban and Environmental Sciences Peking UniversityBeijing100871China Beijing key Lab Plant Resources Research and Development Beijing Technology and Business UniversityBeijing100048China College of Ecology and Environment Zhengzhou UniversityZhengzhou450001China Facultyof Environmental Sciences and Engineering Kunming University of Science and TechnologyYunnan Provincial Key Laboratoryof Soil Carbon Sequestration and Pollution ControlKunming650500China Institute of Carbon Neutrality Peking UniversityBeijing100871China

Biomass is one most abundant resource on the earth providing important energies in support of so-cioeconomic development in many *** of biomass fuels comprises to nearly 10%of the total energy from anthropogenic combustion processes:however,as the burning is usually incomplete,this process yields products of incomplete combustion posing consequently significant impacts on air quality,human health,and climate ***,we analyzed spatiotemporal characteristics in intentional and unintentional biomass burning from different sectors,discussed impacts of biomass burning emissions on indoor and outdoor air quality,and consequent influences on human *** global total con-sumption amount of biomass including both natural and anthropogenic sources was approximately 7900 Tg in 2019,with significantly large regional and sectorial discrepancies among ***,anthropogenic biomass burning amounts increased gradually,but notably in some developing countries like China residential consumption of biomass fuels,as one large sector of biomass use,decreased over *** biomass consumption needs to be accurately *** are relatively rich datasets of pollutant emission factors from biomass burning,including laboratory and field tests,but still large variations exit and contribute substantially to the uncertainty in emission *** pri-mary PM2.5,black carbon and organic carbon emissions from biomass burning were about 51,4.6,and 29 Tg,respectively,contributing to nearly 70%,55%,and 90%of the total emission from all sources,and emissions from the residential sector and open fires are major *** carbon emissions from biomass burning attracts growing interests but available studies adopted different methodologies challenging the comparability of those *** burning emissions polluted not only ambient air but more severely indoor air quality,adversely affecting human *** studies that should be emphasiz

关键词： Biomass burning Carbonaceous aerosol Emission Air quality Human health

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