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China Foundry 2024年第3期21卷 205-212页

作者： Guan-yu Jiang Meng-wu Wu Xiao-guang Yang Hui Wang Yu-yuan zhu Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina Wescast Industries(China)Co. Ltd.Wuhan 430100China

Three types of steels were designed on the basis of GX40CrNiSi25-12 austenitic heat resistant steel by adding different Mn contents(2wt.%,6wt.%,and 12wt.%).Thermodynamic calculation,microstructure characterization and mechanical property tests were conducted to investigate the effect of Mn addition on the microstructure and mechanical properties of the austenitic heat resistant *** show that the matrix structure in all the three types of steels at room temperature is completely *** NbC and M_(23)C_(6)precipitate at grain boundaries of austenite *** the increase of Mn content,the number of carbides increases and their distribution becomes more *** the Mn content increases from 1.99%to 12.06%,the ultimate tensile strength,yield strength and elongation increase by 14.6%,8.0%and 46.3%,*** improvement of the mechanical properties of austenitic steels can be explained by utilizing classic theories of alloy strengthening,including solid solution strengthening,precipitation strengthening,and grain *** increase in alloy strength can be attributed to solid solution strengthening and precipitation strengthening caused by the addition of *** improvement of the plasticity of austenitic steels can be explained from two aspects:grain refinement and homogenization of precipitated phases.

关键词： austenitic heat resistant steel manganese microstructure mechanical properties

A solution method for decomposing vector fields in Hamilton energy

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CHINESE PHYSICS B 2024年第9期33卷 645-653页

作者： Zhao, Xin Yi, Ming Wei, Zhou-Chao zhu, yuan Lu, Lu-Lu China Univ Geosci Sch Math & Phys Wuhan 430074 Peoples R China

Hamilton energy, which reflects the energy variation of systems, is one of the crucial instruments used to analyze the characteristics of dynamical systems. Here we propose a method to deduce Hamilton energy based on the existing systems. This derivation process consists of three steps: step 1, decomposing the vector field; step 2, solving the Hamilton energy function; and step 3, verifying uniqueness. In order to easily choose an appropriate decomposition method, we propose a classification criterion based on the form of system state variables, i.e., type-I vector fields that can be directly decomposed and type-II vector fields decomposed via exterior differentiation. Moreover, exterior differentiation is used to represent the curl of low-high dimension vector fields in the process of decomposition. Finally, we exemplify the Hamilton energy function of six classical systems and analyze the relationship between Hamilton energy and dynamic behavior. This solution provides a new approach for deducing the Hamilton energy function, especially in high-dimensional systems.

关键词： Hamilton energy dynamical systems vector field exterior differentiation 87.19.L- 87.19.Lj 05.45.-a 05.45.Pq INFORMATION-TRANSMISSION CHAOTIC SYSTEM

Degree of shade tolerance shapes seasonality of chlorophyll, nitrogen and phosphorus levels of trees and herbs in a temperate deciduous forest

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Journal of Forestry Research 2024年第4期35卷 60-72页

作者： Jiajia Zeng Fan Liu yuan zhu Jiayi Li Ying Ruan Xiankui Quan Chuankuan Wang Xingchang Wang Aulin College Northeast Forestry UniversityHarbin 150040People’s Republic of China Center for Ecological Research Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021People’s Republic of China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016People’s Republic of China Key Laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin 150040People’s Republic of China

Forest productivity is closely linked to seasonal variations and vertical differentiation in leaf ***,leaf structural and chemical traits variation among co-existing species,and plant functional types within the canopy are poorly *** this study,the seasonality of leaf chlorophyll,nitrogen(N),and phosphorus(P)were quantified vertically along the canopy of four major tree species and two types of herbs in a temperate deciduous *** role of shade tolerance in shaping the seasonal variation and vertical differentiation was *** the entire season,chlorophyll content showed a distinct asymmetric unimodal pattern for all species,with greater chlorophyll levels in autumn than in spring,and the timing of peak chlorophyll per leaf area gradually decreased as shade tolerance *** a:b ratios gradually decreased with increasing shade *** N and P contents sharply declined during leaf expansion,remained steady in the mature stage and decreased again during leaf *** the seasons,the lower canopy layer had significantly higher chlorophyll per leaf mass but not chlorophyll per leaf area than the upper canopy layer regardless of degree of shade ***,N and P per leaf area of intermediate shade-tolerant and fully shade-tolerant tree species were significantly higher in the upper canopy than in the *** variations in N:P ratios suggest changes in N or P *** findings indicate that shade tolerance is a key feature shaping inter-specific differences in leaf chlorophyll,N,and P contents as well as their seasonality in temperate deciduous forests,which have significant implications for modeling leaf photosynthesis and ecosystem production.

关键词： Leaf traits Leaf nutrients Seasonal variations Chlorophyll Nitrogen Phosphorus Shade tolerance Canopy layers

Rapidly growing primordial black holes as seeds of the massive high-redshift JWST Galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 143-150页

作者： Guan-Wen yuan Lei Lei yuan-zhu Wang Bo Wang Yi-Ying Wang Chao Chen Zhao-Qiang Shen Yi-Fu Cai Yi-Zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China Institute of High Energy Physics Chinese Academy of Sciences Deep Space Exploration Laboratory/Department of Astronomy School of Physical SciencesUniversity of Science and Technology of China Jockey Club Institute for Advanced Study The Hong Kong University of Science and Technology

A group of massive galaxies at redshifts of z■7 have been recently detected by the James Webb Space Telescope（JWST）, which were unexpected to form at such an early time within the standard Big Bang cosmology. In this work, we propose that this puzzle can be explained by the presence of some primordial black holes（PBHs） with a mass of ～1000M⊙. These PBHs act as seeds for early galaxy formation with masses of ～10～8-1010M⊙at high redshift, hence accounting for the JWST observations. We use a hierarchical Bayesian inference framework to constrain the PBH mass distribution models, and find that the Lognormal model with the Mc～750M⊙is preferred over other hypotheses. These rapidly growing BHs are expected to have strong radiation and may appear as high-redshift compact objects, similar to those recently discovered by JWST. Although we focused on PBHs in this work, the bound on the initial mass of the seed black holes remains robust even if they were formed through astrophysical channels.

关键词： primordial black hole dark matter halo black hole accretion primordial galaxies

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An electron-transfer[Fe_(2)Co_(2)]square complex exhibiting unprecedented wide room-temperature hysteresis

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Science China Chemistry 2024年第4期67卷 1198-1207页

作者： Xin-Hua Zhao Yi-Fei Deng Jia-Tao Chen Jiong Yang yuan-zhu Zhang Department of Chemistry Southern University of Science and Technology(SUSTech)Shenzhen 518055China

Switchable molecules with magnetic bistability that can function at standard conditions are highly desirable from the perspective of practical *** the last decade,significant progress has been made in modulating thermally induced electrontransfer-coupled spin transition(ETCST)events between diamagnetic{Fe_(LS)^(Ⅱ)(μ-CN)Co_(LS)^(Ⅲ)}and paramagnetic{Fe_(LS)^(Ⅲ)(μ-CN)-Co_(HS)^(Ⅱ)}electron configurations(named LS and HS,respectively,for short)within the Fe/Co mixed-valence cyanometallate ***,we prepared a novel[Fe_(2)Co_(2)]square complex[(pzTp)Fe(CN)_(3)Co(bnbpen)]_(2)[NO_(3)]_(2)·4CH_(3)OH·2.5H_(2)O(1·Solv)and its desolvated phase[(pzTp)Fe(CN)_(3)Co(bnbpen)]_(2)[NO_(3)]_(2)(1),obtained via single-crystal-to-single-crystal(SCSC)*** 1·Solv remaining in the diamagnetic state below room temperature exhibits an irreversible ETCST behavior accompanied by desolvation upon ***,complex 1 displays an unprecedented rate-dependent ETCST behaviour involving with two diamagnetic LS states(a dynamically favoured LS1 state and a thermodynamically favoured LS2state),between which a net one-way transition from LS1 to LS2 is accessible likely via a structural phase transition(SPT)above255 ***,two well separated transition channels(HS?LS1 at around 255 K and HS←→LS2 in the temperature range of 317-350 K)are achieved according to either fast(>20 K/min)or slow rate(<1 K/min),*** a moderate rate of 3 K/min,complex 1 shows a wide hysteresis of 66 K centered at 328 K,the largest yet reported for discrete Fe/Co cyanometallate *** 1 represents the first ETCST example coupled with dynamic SPT,providing a new strategy for manipulating bistability within this fascinating cyanometallate family.

关键词： switchable molecules cyanometallate complexes electron transfer hysteresis structural phase transition

3D-printed Mg-1Ca/polycaprolactone composite scaffolds with promoted bone regeneration

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Journal of Magnesium and Alloys 2024年第3期12卷 966-979页

作者： Xiao Zhao Siyi Wang Feilong Wang yuan zhu Ranli Gu Fan Yang Yongxiang Xu Dandan Xia Yunsong Liu Department of Prosthodontics Peking University School and Hospital of StomatologyBeijing 100081China National Center of Stomatology National Engineering Laboratory for Digital and Material Technology of StomatologyNational Clinical Research Center for Oral DiseasesBeijing Key Laboratory of Digital StomatologyResearch Center of Engineering and Technology for Computerized Dentistry Ministry of HealthNMPA Key Laboratory for Dental MaterialsBeijing 100081China Department of Dental Materials Peking University School and Hospital of StomatologyBeijing 100081China

In bone tissue engineering,polycaprolactone(PCL)is a promising material with good biocompatibility,but its poor degradation rate,mechanical strength,and osteogenic properties limit its *** this study,we developed an Mg-1Ca/polycaprolactone(Mg-1Ca/PCL)composite scaffolds to overcome these *** used a melt blending method to prepare Mg-1Ca/PCL composites with Mg-1Ca alloy powder mass ratios of 5,10,and 20 wt%.Porous scaffolds with controlled macro-and microstructure were printed using the fused deposition modeling *** explored the mechanical strength,biocompatibility,osteogenesis performance,and molecular mechanism of the Mg-1Ca/PCL *** 5 and 10 wt%Mg-1Ca/PCL composites were found to have good ***,they promoted the mechanical strength,proliferation,adhesion,and osteogenic differentiation of human bone marrow stem cells(hBMSCs)of pure *** vitro degradation experiments revealed that the composite material stably released Mg_(2)+ions for a long period;it formed an apatite layer on the surface of the scaffold that facilitated cell adhesion and *** tomography and histological analysis showed that both 5 and 10 wt%Mg-1Ca/PCL composite scaffolds promoted bone regeneration bone *** results indicated that the Wnt/β-catenin pathway was involved in the osteogenic ***,Mg-1Ca/PCL composite scaffolds are expected to be a promising bone regeneration material for clinical *** of significance:Bone tissue engineering scaffolds have promising applications in the regeneration of critical-sized bone ***,there remain many limitations in the materials and manufacturing methods used to fabricate *** study shows that the developed Ma-1Ca/PCL composites provides scaffolds with suitable degradation rates and enhanced boneformation ***,the fused deposition modeling method allows precise control of the macroscopic morphology and microsc

关键词： 3D printing Bone tissue engineering Magnesium Osteogenic Polycaprolactone Scaffold.

Therapeutic effects of Buzhong Yiqi decoction in patients with spleen and stomach qi deficiency after routine surgery and chemotherapy for colorectal cancer

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2183-2193页

作者： Qi Hu Xiao-Pin Chen Zhi-Jun Tang Xue-yuan zhu Chun Liu College of Integrated Traditional Chinese and Western Medicine Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Department of Anorectal Surgery The Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina Department of Anorectal Surgery The First Traditional Chinese Medicine Hospital of ChangdeChangde 415000Hunan ProvinceChina Intensive Care Unit The First Traditional Chinese Medicine Hospital of ChangdeChangde 415000Hunan ProvinceChina

BACKGROUND According to the theory of traditional Chinese medicine(TCM),the spleen and stomach are the basis of acquired nature and the source of qi and blood *** surgery and chemotherapy,patients with colorectal cancer often develop spleen and stomach qi deficiency syndrome,leading to decreased immune *** Yiqi decoction,a classic TCM prescription,has the effect of tonifying middle-jiao and invigorating qi,boosting Yang,and suppressing immune-related ***,it is widely used in the treatment of spleen and stomach qi deficiency *** To investigate the effect of Buzhong Yiqi decoction on spleen and stomach qi deficiency in patients with colorectal *** One hundred patients with colorectal cancer who underwent preoperative chemotherapy and laparoscopy at The First TCM Hospital of Changde from January 2022 to October 2023 were retrospectively *** patients were divided equally into control and observation *** groups underwent conventional rehabilitation surgery,and the observation group was supplemented with Buzhong Yiqi *** 26.0 was used for statistical ***χ2 test was used for univariate analysis;independent sample t-tests were used in all *** No significant differences were observed preoperatively in the general characteristics of the two *** days post-surgery,the abdominal distension,emaciation,loose stool,loss of appetite,and vomiting scores were significantly lower in the observation group than in the control group(P<0.05).Immune function and interleukin(IL)-10 levels in the observation group were significantly higher than those of the control group,whereas IL-6,tumor necrosis factor-α,and C-reactive protein levels,tumor biological indexes,and adverse reactions in the observation group were significantly lower than those of the control group(P<0.05).One month after surgery,the patients’quality of life in the observation group was significantly high

关键词： Buzhong Yiqi decoction Colorectal cancer Laparoscopic radical surgery Immune function Inflammatory mediators Spleen

In Situ Sustained Macrophage-Targeted Nanomicelle-Hydrogel Microspheres for Inhibiting Osteoarthritis

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Research 2024年第1期2023卷 1-16页

作者： XiaoXiao Li Xingchen Li Jielai Yang Yawei Du Liang Chen Gang Zhao Tingjun Ye yuan zhu Xiangyang Xu Lianfu Deng Wenguo Cui Department of Orthopaedics Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint DiseasesShanghai Institute of Traumatology and OrthopaedicsRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025P.R.China

There are stillchallenges in applying drug nanocarriers for in situ sustained macrophage targeting and regulation,due to the rapid clearance of nanocarriers and burst drug release ***,a nanomicellehydrogel microsphere,characterized by its macrophage-targeted nanosized secondary structure that allows it to accurately bind to M1 macrophages through active endocytosis,is employed for in situ sustained macrophage targeting and regulation,and addresses the insufficient osteoarthritis therapeutic efficacy caused by rapid clearance of drug *** 3-dimensional structure of a microsphere can prevent the rapid escape and clearance of a nanomicelle,thus keeping it in joints,while the ligand-guided secondary structure can carry drugs to accurately target and enter M1 macrophages,and release drugs via the transition from hydrophobicity to hydrophilicity of nanomicelles under inflammatory stimulation inside the macrophages.

关键词： micelle release spheres

Endovascular treatment of direct carotid cavernous fistula resulting from rupture of intracavernous carotid aneurysm: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1940-1946页

作者： Guang Ouyang Kai-Li Zheng Kuan Luo Mu Qiao yuan zhu De-Rui Pan Department of Neurosurgery Puren Hospital Affiliated to Wuhan University of Science and TechnologyWuhan 430081Hubei ProvinceChina Department of Neurosurgery The Third Hospital of WuhanWuhan 430081Hubei ProvinceChina

BACKGROUND Direct carotid cavernous fistulas(CCFs)are typically the result of a severe traumatic brain ***-flow arteriovenous shunts secondary to rupture of an intracavernous aneurysm,resulting in direct CCFs,are *** use of a pipeline embolization device in conjunction with coils and Onyx glue for treatment of direct high-flow CCF resulting from ruptured cavernous carotid artery aneurysm in a clinical setting is not well *** SUMMARY A 58-year-old woman presented to our department with symptoms of blepharoptosis and intracranial bruits for 1 *** physical examination,there was right eye exophthalmos and ocular motor *** rest of the neurological examination was ***,the patient had no history of head *** patient was treated with a pipeline embolization device in the ipsilateral internal carotid artery across the *** and Onyx were placed through the femoral venous route,followed by placement of the pipeline embolization device with assistance from a balloon-coiling *** intraoperative or perioperative complications *** symptoms of bulbar hyperemia and bruits subsided immediately after the *** Pipeline embolization device in conjunction with coiling and Onyx may be a safe and effective approach for direct CCFs.

关键词： Intravascular therapy Carotid cavernous fistulas Intracavernous carotid aneurysms Case report

C-F insertion reaction sheds new light on the construction of fluorinated compounds

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Chinese Chemical Letters 2024年第8期35卷 163-169页

作者： Dong-Sheng Deng Su-Qin Tang Yong-Tu yuan Ding-Xiong Xie Zhi-yuan zhu Yue-Mei Huang Yun-Lin Liu Henan Key Laboratory of Function-Oriented Porous Materials and College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyang 471934China School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The atom-economical C-F insertion chemistry is emerged as a promising technology for the synthesis of various fluorinated scaffolds,which have wide applications both in the academic and the industrial *** past three years have witnessed rapid developments in this *** highlight provides an overview on the evolution according to the fluorinating agents used.

关键词： C-F insertion Benzyl fluoride Acyl fluoride gem-Difluorocyclopropane Fluorinated scaffold