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Facile fabrication of graphene/g-C_(3)N_(4) for electromagnetic wave absorption

Nano Research 2024年第3期17卷 1687-1698页

作者： Qiang Su Yunfei He Dongdong liu Daguang Li Long Xia Xiaoxiao Huang bo Zhong School of Materials Science and Engineering Harbin Institute of Technology WeihaiWeihai 264209China Weihai Yunshan Technology Co. Ltd.Weihai 264200China State Key Laboratory on Integrated Optoelectronics College of Electronic Science&EngineeringJilin UniversityChangchun 130012China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

With the development of the miniaturization of electronic equipment and lightweight weapon equipment,there are new requirements for electromagnetic wave absorption material(EMWAM).EMWAM has outstanding electromagnetic wave absorption properties and lightweight characteristics become an important direction of research.In this study,graphene/g-C_(3)N_(4)(GGCN)EMWAM was first synthesized in situ by simple heat treatment,in which the g-C_(3)N_(4) had a porous structure and dispersed on the surface of graphene.The impedance matching of the GGCN was well adjusted by decreasing the dielectric constant and attenuation constant due to the g-C_(3)N_(4) semiconductor property and the graphite-like structure.The EMW loss mechanism of GGCN was also analyzed by simulating GGCN’s electric field mode distribution and resistance loss power density.The analysis result shows that the distribution of g-C_(3)N_(4) among GGCN sheets can produce more polarization effects and relaxation effects by increasing the lamellar spacing.Furthermore,the polarization loss of GGCN could be increased successfully by porous g-C_(3)N_(4).Ultimately,the EMW absorption property of GGCN is optimized significantly,and GGCN exhibits excellent EMW absorption performance.When the thickness is 2 mm,the effective absorption bandwidth(EAB)can reach 4.6 GHz,and when the thickness is 4.5 mm,the minimum reflection loss(RLmin)at 4.56 GHz can reach-34.69 dB.Moreover,the practical application of EMWAM was studied by radar cross-section(RCS)simulation,showing that GGCN has a good application prospect.

关键词： graphene/g-C_(3)N_(4) impedance matching simulation analysis dielectric loss excellent electromagnetic wave absorption

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The mechanisms of thermal solidification agent promoting steam diversion in heavy oil reservoirs

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Petroleum Science 2024年第3期21卷 1902-1914页

作者： Zhan-Xi Pang Qian-Hui Wang Qiang Meng bo Wang Dong liu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) Liaohe Oilfield Institute CNPC China Henan Oilfield Institute Sinopec China Tianjin Branch of China National Offshore Oil Company (CNOOC) Ltd.

At high cycles of steam huff & puff, oil distribution in reservoirs becomes stronger heterogeneity due to steam channeling. Thermal solidification agent can be used to solve this problem. Its solution is a lowviscosity liquid at normal temperature, but it can be solidified above 80°C. The plugging degree is up to 99% at 250°C. The sweep efficiency reaches 59.2%, which is 7.3% higher than pure steam injection. In addition, simultaneous injection of viscosity reducer and/or nitrogen foams can further enhance oil recovery. The mechanism of this technology depends on its strong plugging ability, which changes the flowing pattern of steam to effectively mobilize remaining oil. Viscosity reducer and nitrogen foams further expand the sweep range and extends the effective period. Therefore, thermal solidification agent can plug steam channeling paths and adjust steam flowing direction to significantly enhance oil recovery at high cycles of steam huff & puff.

关键词： Heavy oil reservoir Steam huff & puff Steam channeling Steam diversion Plugging performance Mechanism analysis

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Influence of layer thickness on formation quality,microstructure,mechanical properties,and corrosion resistance of WE43 magnesium alloy fabricated by laser powder bed fusion

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Journal of Magnesium and Alloys 2024年第4期12卷 1367-1385页

作者： Bangzhao Yin Jinge liu bo Peng Mengran Zhou Bingchuan liu Xiaolin Ma Caimei Wang Peng Wen Yun Tian Yufeng Zheng State Key Laboratory of Tribology in Advanced Equipment Beijing100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Institute for Precision Medicine Tsinghua UniversityBeijing102218China Department of Orthopaedics Peking University Third HospitalBeijing 100191China Beijing AKEC Medical Co. Ltd.Beijing 102200China School of Materials Science and Engineering Peking UniversityBeijing 100871China Engineering Research Center of bone and Joint Precision Medicine Ministry of EducationBeijing 100191China

Laser powder bed fusion(L-PBF)of Mg alloys has provided tremendous opportunities for customized production of aeronautical and medical parts.Layer thickness(LT)is of great significance to the L-PBF process but has not been studied for Mg alloys.In this study,WE43 Mg alloy bulk cubes,porous scaffolds,and thin walls with layer thicknesses of 10,20,30,and 40μm were fabricated.The required laser energy input increased with increasing layer thickness and was different for the bulk cubes and porous scaffolds.Porosity tended to occur at the connection joints in porous scaffolds for LT40 and could be eliminated by reducing the laser energy input.For thin wall parts,a large overhang angle or a small wall thickness resulted in porosity when a large layer thicknesses was used,and the porosity disappeared by reducing the layer thickness or laser energy input.A deeper keyhole penetration was found in all occasions with porosity,explaining the influence of layer thickness,geometrical structure,and laser energy input on the porosity.All the samples achieved a high fusion quality with a relative density of over 99.5%using the optimized laser energy input.The increased layer thickness resulted to more precipitation phases,finer grain sizes and decreased grain texture.With the similar high fusion quality,the tensile strength and elongation of bulk samples were significantly improved from 257 MPa and 1.41%with the 10μm layer to 287 MPa and 15.12%with the 40μm layer,in accordance with the microstructural change.The effect of layer thickness on the compressive properties of porous scaffolds was limited.However,the corrosion rate of bulk samples accelerated with increasing the layer thickness,mainly attributed to the increased number of precipitation phases.

关键词： Magnesium alloy WE43 Laser powder bed fusion Layer thickness Process optimization

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Improving corrosion resistance of additively manufactured WE43 magnesium alloy by high temperature oxidation for biodegradable applications

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Journal of Magnesium and Alloys 2024年第3期12卷 940-953页

作者： Jinge liu Bangzhao Yin Fei Song Bingchuan liu bo Peng Peng Wen Yun Tian Yufeng Zheng Xiaolin Ma Caimei Wang State Key Laboratory of Tribology in Advanced Equipment Beijing100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Department of Orthopaedics Beijing Tsinghua Changgung HospitalInstitute for Precision MedicineTsinghua UniversityBeijing102218China Department of Orthopaedics Peking University Third HospitalBeijing 100191China Engineering Research Center of bone and Joint Precision Medicine Ministry of EducationBeijing 100191China School of Materials Science and Engineering Peking UniversityBeijing 100871China Beijing AKEC Medical Co. Ltd.Beijing 102200China

Laser powder bed fusion(L-PBF)has been employed to additively manufacture WE43 magnesium(Mg)alloy biodegradable implants,but WE43 L-PBF samples exhibit excessively rapid corrosion.In this work,dense WE43 L-PBF samples were built with the relativity density reaching 99.9%.High temperature oxidation was performed on the L-PBF samples in circulating air via various heating temperatures and holding durations.The oxidation and diffusion at the elevated temperature generated a gradient structure composed of an oxide layer at the surface,a transition layer in the middle and the matrix.The oxide layer consisted of rare earth(RE)oxides,and became dense and thick with increasing the holding duration.The matrix was composed ofα-Mg,RE oxides and Mg_(24)RE_(5) precipitates.The precipitates almost disappeared in the transition layer.Enhanced passivation effect was observed in the samples treated by a suitable high temperature oxidation.The original L-PBF samples lost 40%weight after 3-day immersion in Hank’s solution,and broke into fragments after 7-day immersion.The casted and solution treated samples lost roughly half of the weight after 28-day immersion.The high temperature oxidation samples,which were heated at 525℃ for 8 h,kept the structural integrity,and lost only 6.88%weight after 28-day immersion.The substantially improved corrosion resistance was contributed to the gradient structure at the surface.On one hand,the outmost dense layer of RE oxides isolated the corrosive medium;on the other hand,the transition layer considerably inhibited the corrosion owing to the lack of precipitates.Overall,high temperature oxidation provides an efficient,economic and safe approach to inhibit the corrosion of WE43 L-PBF samples,and has promising prospects for future clinical applications.

关键词： Laser powder bed fusion Biodegradable magnesium alloy High temperature oxidation Corrosion resistance WE43.

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Achieving Ultra-Broad Microwave Absorption Bandwidth Around Millimeter-Wave Atmospheric Window Through an Intentional Manipulation on Multi-Magnetic Resonance Behavior

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Nano-Micro Letters 2024年第9期16卷 291-307页

作者： Chuyang liu Lu Xu Xueyu Xiang Yujing Zhang Li Zhou bo Ouyang Fan Wu Dong‑Hyun Kim Guangbin Ji School of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016JiangsuPeople’s Republic of China School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuPeople’s Republic of China School of Physics Nanjing University of Science and TechnologyNanjing 210094JiangsuPeople’s Republic of China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuPeople’s Republic of China School of Physics Chungbuk National UniversityCheongju 28644South Korea Department of Chemistry School of ScienceTianjin UniversityTianjin 300072People’s Republic of China

The utilization of electromagnetic waves is rapidly advancing into the millimeter-wave frequency range,posing increasingly severe challenges in terms of electromagnetic pollution prevention and radar stealth.However,existing millimeter-wave absorbers are still inadequate in addressing these issues due to their monotonous magnetic resonance pattern.In this work,rare-earth La^(3+)and non-magnetic Zr^(4+)ions are simultaneously incorporated into M-type barium ferrite(BaM)to intentionally manipulate the multi-magnetic resonance behavior.By leveraging the contrary impact of La^(3+)and Zr^(4+)ions on magnetocrystalline anisotropy field,the restrictive relationship between intensity and frequency of the multi-magnetic resonance is successfully eliminated.The magnetic resonance peak-differentiating and imitating results confirm that significant multi-magnetic resonance phenomenon emerges around 35 GHz due to the reinforced exchange coupling effect between Fe^(3+)and Fe^(2+)ions.Additionally,Mosbauer spectra analysis,first-principle calculations,and least square fitting collectively identify that additional La^(3+)doping leads to a profound rearrangement of Zr^(4+)occupation and thus makes the portion of polarization/conduction loss increase gradually.As a consequence,the La^(3+)-Zr^(4+)co-doped BaM achieves an ultra-broad bandwidth of 12.5+GHz covering from 27.5 to 40+GHz,which holds remarkable potential for millimeter-wave absorbers around the atmospheric window of 35 GHz.

关键词： Microwave absorption Ultra-broad bandwidth M-type barium ferrite Magnetocrystalline anisotropy field Multimagnetic resonance

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Risk Assessment of Deep-Water Horizontal X-Tree Installation

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China Ocean Engineering 2024年第2期38卷 210-220页

作者： MENG Wen-bo FU Guang-ming HUANG Yi liu Shu-jie HUANG Liang GAOYong-hai CNOOC China Limited Zhanjiang BranchZhanjiang 524057China Key Laboratory of Unconventional Oil and Gas Development Ministry of Education(China University of Petroleum(East China))Qingdao 266580China

Due to the high potential risk and many influencing factors of subsea horizontal X-tree installation,to guarantee the successful completion of sea trials of domestic subsea horizontal X-trees,this paper established a modular risk evaluation model based on a fuzzy fault tree.First,through the analysis of the main process oftree down and combining the Offshore&Onshore Reliability Data(OREDA)failure statistics and the operation procedure and the data provided by the job,the fault tree model of risk analysis of the tree down installation was established.Then,by introducing the natural language of expert comprehensive evaluation and combining fuzzy principles,quantitative analysis was carried out,and the fuzzy number was used to calculate the failure probability of a basic event and the occurrence probability of a top event.Finally,through a sensitivity analysis of basic events,the basic events of top events significantly affected were determined,and risk control and prevention measures for the corresponding high-risk factors were proposed for subsea horizontal X-tree down installation.

关键词： subsea horizontal X-tree risk assessment fuzzy fault tree modular risk evaluation model

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Nrf2-mediated ferroptosis of spermatogenic cells involved in male reproductive toxicity induced by polystyrene nanoplastics in mice

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 307-323页

作者： Xufeng FU Hang HAN Hong YANG bo XU Wenjie DAI Ling liu Tiantian HE Xing DU Xiuying PEI Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education School of Basic Medical SciencesNingxia Medical UniversityYinchuan 750004China Key Laboratory of Reproduction and Genetics in Ningxia Ningxia Medical UniversityYinchuan 750004China

Microplastics(MPs)and nanoplastics(NPs)have become hazardous materials due to the massive amount of plastic waste and disposable masks,but their specific health effects remain uncertain.In this study,fluorescence-labeled polystyrene NPs(PS-NPs)were injected into the circulatory systems of mice to determine the distribution and potential toxic effects of NPs in vivo.Interestingly,whole-body imaging found that PS-NPs accumulated in the testes of mice.Therefore,the toxic effects of PS-NPs on the reproduction systems and the spermatocytes cell line of male mice,and their mechanisms,were investigated.After oral exposure to PS-NPs,their spermatogenesis was affected and the spermatogenic cells were damaged.The spermatocyte cell line GC-2 was exposed to PS-NPs and analyzed using RNA sequencing(RNA-seq)to determine the toxic mechanisms;a ferroptosis pathway was found after PS-NP exposure.The phenomena and indicators of ferroptosis were then determined and verified by ferroptosis inhibitor ferrostatin-1(Fer-1),and it was also found that nuclear factor erythroid 2-related factor 2(Nrf2)played an important role in spermatogenic cell ferroptosis induced by PS-NPs.Finally,it was confirmed in vivo that this mechanism of Nrf2 played a protective role in PS-NPs-induced male reproductive toxicity.This study demonstrated that PS-NPs induce male reproductive dysfunction in mice by causing spermatogenic cell ferroptosis dependent on Nrf2.

关键词： Polvstyrene nanoplastics(PS-NPs) Reproductive toxicity Ferroptosis Nuclear factor ervthroid 2-related factor 2(Nrf2)

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Neuroprotective effects of acteoside in a glaucoma mouse model by targeting Serta domain-containing protein 4

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 625-637页

作者： Hui-Jie Hao Ya-Hong Li bo Yu Xun liu Yan Zhang Xiao-Li Xing Tianjin Key Laboratory of Retinal Functions and Diseases Tianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China

AIM:To explore the therapeutic effect and main molecular mechanisms of acteoside in a glaucoma model in DBA/2J mice.METHODS:Proteomics was used to compare the differentially expressed proteins of C57 and DBA/2J mice.After acteoside administration in DBA/2J mice,anterior segment observation,intraocular pressure(IOP)monitoring,electrophysiology examination,and hematoxylin and eosin staining were used to analyze any potential effects.Immunohistochemistry(IHC)assays were used to verify the proteomics results.Furthermore,retinal ganglion cell 5(RGC5)cell proliferation was assessed with cell counting kit-8(CCK-8)assays.Serta domain-containing protein 4(Sertad4)mRNA and protein expression levels were measured by qRT-PCR and Western blot analysis,respectively.RESULTS:Proteomics analysis suggested that Sertad4 was the most significantly differentially expressed protein.Compared with the saline group,the acteoside treatment group showed decreased IOP,improved N1-P1 wave amplitudes,thicker retina,and larger numbers of cells in the ganglion cell layer(GCL).The IHC results showed that Sertad4 expression levels in DBA/2J mice treated with acteoside were significantly lower than in the saline group.Acteoside treatment could improve RGC5 cell survival and reduce the Sertad4 mRNA and protein expression levels after glutamate injury.CONCLUSION:Sertad4 is differentially expressed in DBA/2J mice.Acteoside can protect RGCs from damage,possibly through the downregulation of Sertad4,and has a potential use in glaucoma treatment.

关键词： glaucoma acteoside Serta domaincontaining protein 4 proteomics mice

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Identifying the effective combination of acupuncture and traditional Chinese medicinal herbs for postmenopausal osteoporosis therapy through studies of their molecular regulation of bone homeostasis

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Journal of Traditional Chinese Medicine 2024年第1期44卷 212-219页

作者： REN Ping WANG Quanwu BAI Wei SUN Miao liu Zheling GAO Ming WANG Liang PENG bo XU Liguang Department of Health Management the Third Affiliated Clinical Hospital of Changchun University of Chinese MedicineChangchun 130117China Department of Dirty Tuina the affiliated Hospital to Changchun University of Chinese MedicineChangchun 130117China Department of Acupuncture the affiliated Hospital to Changchun University of Chinese MedicineChangchun 130117China Department of Rehabilitation Medicine the 924th Hospital of the PLA Joint Logistic Support ForceFoshan 528226China Department of College of Acupuncture and Massage Changchun University of Chinese MedicineChangchun 130117China

Worldwide,as the population age,osteoporosis is becoming increasingly common,and osteoporotic fractures have a significant economic burden.Postmenopausal women are the most susceptible to developing osteoporosis and the most critical time to prevent it is during the perimenopausal and early menopausal years.In this regard,we hypothesize rational combination of acupuncture and Traditional Chinese Medicine(TCM)in the form of herbal extract could prevent osteoporosis in women.Estrogen deficiency during menopause causes low-level inflammation that stimulates the formation of osteoclasts,the boneresorbing cells,and simultaneously inhibits the viability and function of osteoblasts,the bone-forming cells.The most potent inflammatory cytokine in skeletal homeostasis is the receptor activator of nuclear factor kappa B ligand(RANKL)that stimulates osteoclast function.Conversely,the canonical Wnt pathway is essential for osteoblastogenesis and bone formation,and estrogen deficiency leads to diminished functioning of this pathway.TCM and acupuncture could target the RANKL and the Wnt pathway in favorable ways to prevent the accelerated bone loss experienced during the early menopausal stage and promote the gain in bone mass in postmenopausal women.In this review,we propose a rational combination of specific TCM and acupuncture targeting those signaling molecules/pathways by the drugs that are in clinical use for the treatment of postmenopausal osteoporosis.Our rational approach revealed that Danshen(Radix Salviae Miltiorrhizae)could exert a synergistic effect with acupuncture.We then propose a translational path for developing the putative combination in women with postmenopausal osteoporosis to curtail the risk of osteoporotic fractures.

关键词： medicine traditional osteogenic anti-resorptive review

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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 diagnosis.METHODS: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 hospital.Next,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 regression.Besides,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 testing.The 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 treatment.RESULTS:ONOO-levels of AH and plasma were significantly higher in the POAG group than in the ARC group(P<0.01).Additionally,ONOO-levels were closely correlated with POAG in a binary logistic regression analysis[odds ratio(OR)=1.008,95%confidence interval(CI):1.002-1.013,P<0.01 for AH;OR=1.004,95%CI:1.002-1.006,P<0.001 for plasma].Pearson correlation analysis showed that ONOO-levels in AH or plasma were positively associated with visual field defects(R=0.51,P<0.01 for AH;R=0.45,P<0.001 for plasma),and ONOO-levels in plasma and AH were correlated in the POAG group(R=0.69,P<0.001).However,administering MnTMPyP to mouse eyes reversed the elevated IOP caused by SIN-1(P<0.05).CONCLUSION:ONOO-levels in AH and plasma,detected by RN-NA,are significantly related to POAG and positively correlated with visual field defects in POAG patients.Hence,ONOO-is a potential biomarker of POAG,especially advanced POAG.Besides,anti-nitration compounds may be novel ocular hypotensive agents based on the animal study.

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

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