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improved damage tolerance and oxidation resistance of (Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)ta_(0.2))B_(2)–SiC by introducing chopped carbon fibers

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Journal of Advanced Ceramics 2024年第1期13卷 101-112页

作者： Feilong Huang Hailong wang Cheng Fang Mingliang Li Gang Shao Jinpeng Zhu Yanchun Zhou School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

High-entropy diborides(HEBs)are considered as promising high-temperature structure materials owing to their high melting point and excellent thermal ***,the intrinsic brittleness is the main obstacle that seriously limits their practical *** overcome with this obstacle,carbon fibers(Cf)with outstanding mechanical properties are used in the present work as a first attempt to improve the damage tolerance of *** as-prepared C_(f)/(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)ta_(0.2))B_(2)–SiC composite(C_(f)/HEB–SiC)shows high relative density(97.9%)and good mechanical properties with flexural strength of 411±3 MPa and fracture toughness of 6.15±0.11 MPa·m^(1/2).More importantly,the damage tolerance parameter(Dt)has increased from 0.10 m^(1/2) for HEB–SiC to 0.29 m^(1/2) for C_(f)/HEB–*** microstructural analysis and Vickers indentation of the composite,the toughening mechanisms are *** carbon fibers coated with carbon coatings demonstrate unique capacity for prolonging the crack propagation path,which promotes the reliability of the composite ***,the C_(f)/(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)ta_(0.2))B_(2)–SiC composite also exhibits good static oxidation resistance in the temperature range of 1100–1500℃in air due to the formation of the protective oxide layer constituting of multicomponent oxides(Zr)HfTiO4 and(Zr)Hf_(6)ta_(2)O_(17) embedded in a continuous SiO_(2) *** results are promising,and this primary work can be used as a reference to the synthesis of C_(f)/HEBs for thermal protection materials under hightemperature serving conditions.

关键词： high-entropy ceramics carbon fibers(Cf) toughening mechanisms oxidation resistance

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Effect of ta_(2)O_(5)nanoparticles on bioactivity,composition,structure,in vitro and in vivo behavior of PEO coatings on Mg-alloy

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Journal of Magnesium and Alloys 2024年第6期12卷 2360-2379页

作者： D.V.Mashtalyar i.M.imshinetskiy V.V.Kashepa K.V.Nadaraia M.A.Piatkova A.i.Pleshkova K.A.Fomenko A.Yu.Ustinov S.L.Sinebryukhov S.V.Gnedenkov institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far Eastern Federal University Vladivostok690950Russia Regional Clinical Dermatovenerological Dispensary Vladivostok690033Russia

The present study investigates the physical and chemical characteristics,behavior in vitro and in vivo,and biocompatibility of coatings containing ta_(2)O_(5),which are obtained by plasma electrolytic oxidation(PEO)on MA8 magnesium *** obtained coatings demonstrate in vivo biocompatibility and in vitro *** to the base PEO coating,the layers containing ta_(2)O_(5)facilitate the development of apatite in simulated body fluid,suggesting that the inclusion of nanoparticles improves bioactivity of the *** was found that incorporation of ta_(2)O_(5)nanoparticles increases roughness and porosity of the formed layers by increasing particle concentration in electrolytes for the PEO process contributing to sufficient soft tissue ingrowth in *** on in vivo studies,these coatings also provide favorable tissue response and minimal inflammatory reaction in comparison with the bare magnesium alloy due to protection of living tissues from deleterious corrosion events of magnesium implant such as local alkalization and intense hydrogen *** results obtained in the present study concluded biocompatibility,tissue integration of the PEO coatings containing ta_(2)O_(5)nanoparticles making them a promising protective layer for biodegradable magnesium implants.

关键词： Plasma electrolytic oxidation Bioactive coatings tantalum pentoxide Simulated body fluid(SBF) Apatite formation Histology

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Nb-and ta-doped(Hf,Zr,Ti)C multicomponent carbides with enhanced oxidation resistance at 2500℃

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Journal of Advanced Ceramics 2024年第3期13卷 332-344页

作者： Shiyan Chen Jinming wang Zhaoke Chen Weilong Song Yi Zeng Xingchao Li Tongqi Li Xiang Xiong State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Aerospace Research institute of Materials&Processing Technology China Academy of Launch Vehicle TechnologyBeijing 100076China

Enhancing oxidation resistance of multicomponent carbides above 2000℃is critical for their thermal protection *** this purpose,novel Nb-and ta-doped(Hf,Zr,Ti)C multicomponent carbides were designed to improve their oxidation resistance at 2500℃.The results demonstrated that Nb and ta doping reduced the oxidation rate constant by 16.67%and 25.17%,respectively,thereby significantly improving the oxidation resistance of(Hf,Zr,Ti)*** enhancement was attributed to the changes in oxycarbide composition and distribution within the oxide layer by adding Nb and *** to the different oxidation tendencies of the constituent elements,a distinctive structure was formed in which(Hf,Zr)O_(2)served as a skeleton,and various oxycarbides were dispersed throughout the oxide *** doped Nb and ta were retained within oxycarbides,retarding the diffusion of oxygen into the *** importantly,the addition of Nb and ta reduced the size of oxycarbides,decreasing both size and quantity of the pores in the oxide layer and facilitating the formation of a more effective oxygen barrier.

关键词： (Hf,Zr,Ti)C oxidation behaviour ultra-high-temperature oxidation Nb and ta doping oxycarbides

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Ultrafast investigation of room temperature valley polarization in“optical bilayer”WS_(2)

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Science China(Technological Sciences) 2024年第1期67卷 91-97页

作者： ZHAO LeYi wang Hai LiU TianYu Li FangFei ZHOU Qiang wang HaiYu Synergetic Extreme Condition High-Pressure Science Center State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China State Key Laboratory of integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

Monolayer transition metal dichalcogenides(TMDCs)have become a promising platform in valleytronics due to possessing the regulatable valley degrees of ***,as a result of the rapid intervalley scattering,it is difficult to measure the PL valley polarization of monolayer TMDCs at room temperature,which limits their application in valleytronics ***,we report a room temperature photoluminescence(PL)valley polarization up to 3.73%in an“optical bilayer”WS_(2)formed by transferring monolayer WS_(2)onto flat Ag ***,in the transient absorption(ta)measurements,a remarkably long valley depolarization lifetime is ***,we demonstrate the valley properties of such“optical bilayer”WS_(2)resemble actual bilayer WS_(2),in which the robust valley polarization can be attributed to the phonons depletion effect and the blocked interlayer hopping *** peculiar valley features in“optical bilayer”WS_(2)provide a particularly simple method to enhance valley control at room temperature.

关键词： valleytronics optical bilayer transient absorption tungsten disulfide

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Experimental realization of fractal fretwork metasurface for sound anomalous modulation

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Chinese Physics B 2024年第5期33卷 473-478页

作者：何佳杰于书萌江雪他得安 Department of Biomedical Engineering School of Information Science and TechnologyFudan UniversityShanghai 200433China Academy for Engineering and Technology Fudan UniversityShanghai 200433China

Natural creatures and ancient cultures are full of potential sources to provide inspiration for applied *** by the fractal geometry in nature and the fretwork frame in ancient culture,here we design the acoustic metasurface to realize sound anomalous modulation,which manifests itself as an incident-dependent propagation behavior:sound wave propagating in the forward direction is allowed to transmit with high efficiency while in the backward direction is obviously *** quantitatively investigate the dependences of asymmetric transmission on the propagation direction,incident angle and operating frequency by calculating sound transmittance and energy *** compact fractal fretwork metasurface for acoustic anomalous modulation would promote the development of integrated acoustic devices and expand versatile applications in acoustic communication and information encryption.

关键词： acoustic metasurface fractal geometry sound anomalous modulation

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Stercoral perforation of the cecum:A case report

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1189-1194页

作者： Hung-Chun Yu ta-Wei Pu Jung-Cheng Kang Chao-Yang Chen Je-Ming Hu Ruei-Yu Su Department of Surgery Taichung Armed Forces General HospitalTaichung 411228Taiwan Department of Surgery Tri-Service General HospitalNational Defense Medical CenterTaipei 11490Taiwan Division of Colon and Rectal Surgery Department of SurgeryTri-Service General Hospital Songshan BranchNational Defense Medical CenterTaipei 105Taiwan Division of Colon and Rectal Surgery Department of SurgeryTaiwan Adventist HospitalTaipei 105Taiwan Division of Colon and Rectal Surgery Department of SurgeryTri-Service General HospitalNational Defense Medical CenterTaipei 114Taiwan Department of Pathology Tri-Service General HospitalNational Defense Medical CenterTaipei 105Taiwan Department of Pathology and Laboratory Medicine Taoyuan Armed Forces General HospitalTaoyuan 325Taiwan

BACKGROUND With less than 90 reported cases to date,stercoral perforation of the colon is a rare *** ulceration is thought to occur due to ischemic pressure necrosis of the bowel wall,which is caused by the presence of a stercoraceous *** underscore this urgent surgical situation concerning clinical presentation,surgical treatment,and results,we present the case of a 66-year-old man with a stercoral *** SUMMARY A 66-year-old man with a history of hypertension,hyperlipidemia,and gout presented at the emergency department with lower abdominal pain and a low-grade fever lasting for a few *** computed tomography indicated a suspected bezoar(approximately 7.6 cm)in the dilated cecum,accompanied by pericolic fat stranding,mild proximal dilatation of the ileum,pneumoperitoneum,and minimal ***,feculent peritonitis with isolated cecal perforation were ***,a right hemicolectomy with peritoneal lavage was performed.A histopathological examination supported the intraoperative *** in stercoral perforations,a diagnosis should be diligently pursued,especially in older adults,and prompt surgical intervention should be implemented.

关键词： Acute abdomen Colectomy Peritoneal lavage Pneumoperitoneum Bezoars Case report

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Mucinous neoplasm of the appendix:A case report and review of literature

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 944-954页

作者： Hao-Cheng Chang Jung-Cheng Kang ta-Wei Pu Ruei-Yu Su Chao-Yang Chen Je-Ming Hu Department of Surgery Tri-Service General HospitalTaipei 114TaiwanChina Division of Colon and Rectal Surgery Department of SurgeryTaiwanChina Adventist HospitalTaipei 105TaiwanChina Division of Colon and Rectal Surgery Department of SurgeryTri-Service General Hospital Songshan BranchNational Defense Medical CenterTaipei 105TaiwanChina Division of Colon and Rectal Surgery Department of SurgeryTri-Service General HospitalNational Defense Medical CenterTaipei 114TaiwanChina Department of Pathology Tri-Service General HospitalNational Defense Medical CenterTaipei 105TaiwanChina Department of Pathology and Laboratory Medicine Taoyuan Armed Forces General HospitalTaoyuan 325TaiwanChina

BACKGROUND Appendiceal mucinous neoplasms(AMNs),although not classified as rare,are relatively uncommon tumors most often discovered incidentally during colorectal *** identification of AMNs is difficult due to non-specific sym-ptoms,overlapping tumor markers with other conditions,and the potential for *** underscores the urgent need for precision in diagnosis to pre-vent severe *** SUMMARY This case report describes the unexpected discovery and treatment of a low-grade AMN(LAMN)in a 74-year-old man undergoing laparoscopic hemicolectomy for transverse colon adenocarcinoma(AC).Preoperatively,non-specific gastroin-testinal symptoms and elevated tumor markers masked the presence of *** tumor,presumed to be an AMN peritoneal cyst intraoperatively,was con-firmed as LAMN through histopathological *** neoplasm exhibited mucin accumulation and a distinct immunohistochemical profile:Positive for Ho-meobox protein CDX-2,Cytokeratin 20,special AT-rich sequence-binding protein 2,and Mucin 2 but negative for cytokeratin 7 and Paired box gene *** profile aids in distinguishing appendiceal and ovarian mucinous *** recovery was uncomplicated,and the patient initiated adjuvant chemotherapy for the colon *** This case highlights the diagnostic complexity of AMNs,emphasizing the need for vigilant identification to avert potential complications,such as pseudomyxoma peritonei.

关键词： Adenocarcinoma Appendiceal neoplasms Low-grade appendiceal mucinous neoplasm Peritoneal neoplasms Pseudomyxoma peritonei Case report

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Colon perforation with severe peritonitis caused by erotic toy insertion and treated using vacuum-assisted closure:A case report

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World Journal of Clinical Cases 2024年第18期12卷 3548-3554页

作者： Cheng-You Lin ta-Wei Pu Department of Surgery Division of Colon and Rectal SurgeryTri-Service General HospitalNational Defense Medical CenterTaipei 114Taiwan Department of Surgery Taichung Armed Force General HospitalTaichung 411Taiwan Division of Colon and Rectal Surgery Department of SurgeryTri-Service General Hospital Songshan branchNational Defense Medical CenterTaipei 105Taiwan

BACKGROUND Colorectal foreign bodies are commonly encountered during *** are frequently observed in men 20 to 90 years of age and have bimodal age *** management is necessary for cases of rectal ***,surgical site infections are the most common complications after colorectal *** SUMMARY We discuss a case of rectal perforation in a patient who presented to our hospital 2 d after its *** perforation occurred as a result of the patient inserting a sex toy in his *** peritonitis was attributable to delayed *** Vacuum-assisted closure was performed to treat the wound,which healed well after *** complications were noted.

关键词： Colorectal surgery Foreign bodies intestinal perforation Surgical site infection Wound closure techniques Case report

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甘蓝型油菜种子硫代葡萄糖苷含量的QTL定位及候选基因分析

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西北植物学报 2024年第8期44卷 1261-1272页

作者：赵卫国塔娜王灏安康学院现代农业与生物科技学院陕西安康725000 陕西省杂交油菜研究中心陕西杨凌712100

【目的】解析甘蓝型油菜种子硫代葡萄糖苷性状的重要遗传位点及候选基因,为甘蓝型油菜硫苷基因克隆和品种品质改良奠定基础。【方法】以甘蓝型油菜KN DH群体种子为材料,对在4个种植环境的种子硫苷含量进行QTL定位和候选基因分析。【结果... 详细信息

【目的】解析甘蓝型油菜种子硫代葡萄糖苷性状的重要遗传位点及候选基因,为甘蓝型油菜硫苷基因克隆和品种品质改良奠定基础。【方法】以甘蓝型油菜KN DH群体种子为材料,对在4个种植环境的种子硫苷含量进行QTL定位和候选基因分析。【结果】(1)甘蓝型油菜种子硫苷含量变异系数较高且较为稳定,服从数量性状的遗传特点。(2)7个一致性QTL(cqGC.A9-5、cqGC.A9-7、cqGC.A9-9、cqGC.C2-9、cqGC.C2-10、cqGC.C9-5和cqGC.C9-6)为环境稳定表达QTL,包括3个主效QTL(cqGC.A9-5、cqGC.C2-10和cqGC.C9-5)。(3)在主效QTL cqGC.A9-5和cqGC.C9-5鉴定到3个候选基因(BnaA09g05480D、BnaC09g05620D和BnaC09g05810D),主要涉及硫苷生物合成途径中吲哚-3-乙醛肟、3-烷基-苹果酸的合成及硫苷的转运与分配。【结论】甘蓝型油菜种子硫苷含量为数量性状。3个甘蓝型油菜硫苷含量主效QTL被鉴定到,其置信区间候选基因的拟南芥同源基因参与硫苷合成途径中间产物合成及促进硫苷的转运与分配。

关键词：甘蓝型油菜种子硫苷含量 QTL定位候选基因

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High-Efficiency Wideband Transmitarray Antenna Using Polarization-Rotating Elements with Parasitic Stubs

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Chinese Journal of Electronics 2024年第2期33卷 496-503页

作者： Xi wang Yuandan DONG University of Electronic Science and Technology of China

A high-efficiency polarization-rotating transmitarray antenna(ta) using wideband elements is proposed for millimeter-wave applications. The polarization-rotating element consists of three metallic layers and two substrates. Orthogonal polarizers are employed on the top and bottom of the element. And the split ring with a parasitic stub on the middle layer is symmetric about the diagonal, performing the polarization rotation and phase compensation simultaneously. A parasitic stub is designed to decrease transmission loss and broaden the bandwidth. The periodicity of the element is only 1/4 wavelength at 30 GHz. A prototype ta with 28 × 28 elements is designed, fabricated, and measured. The measured peak gain reaches 27.5 d Bi at 37.8 GHz. The 1-d B gain drop bandwidth is 30.8–40 GHz(26.0%).The aperture efficiency reaches as high as 71% at 31.5 GHz. Within the bandwidth of 26.5–38.8 GHz(37.7%), the aperture efficiency is higher than 50%. The proposed polarization-rotating ta features wide bandwidth and high efficiency, demonstrating great application potential for 5G millimeter-wave communication.

关键词： Wavelength measurement Transmitting antennas Prototypes Apertures Gain measurement Propagation losses Broadband antennas

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