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Microstructural Evolutions and Mechanical Properties of Energetic Al_(1) (TiZrNbTaMoCr)_(15) High-Entropy Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 620-632页

作者： xuan-Hong cai Zhen-Hua Wang Ben Niu Jin-Feng Li Qing Wang Show authors Key Laboratory of Materials Modification By Laser Ion and Electron Beams(Ministry of Education)Engineering Research Center of High Entropy Alloy Materials(Liaoning Province)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Institute of Materials China Academy of Engineering PhysicsMianyang621908China

The present study focuses on investigating the microstructural evolutions and mechanical properties of energetic Al_(1)(TiZrNbTaMoCr)_(15) refractory high-entropy alloys with the different heat treatments at low Al content state. It is found that even with a reduction in the Al content, the strength of these alloys remains unaffected at room temperature and high temperature, while the plasticity improves significantly. In particular, the coherent BCC/B_(2) microstructure with needle-like B_(2) nanoprecipitates dispersed into the BCC matrix is formed in 873 K-aged Al_(1)Ti_(6)Zr_(2)Nb_(3)Ta_(3)Mo_(0.5)Cr_(0.5) alloy. Therefore, this alloy exhibits the highest compression yield strength (σ_(YS) = 1333 and 717 MPa) at room temperature and 1073 K, respectively. After 973 K-aged, the coherent BCC/B_(2) microstructure underwent destabilization, and the B_(2) phase transforms into the brittle Zr5Al3 phase which then coarsens and dominates the microstructure of S3-AlTa_(3) alloy after 1073 K-aged. Moreover, these current alloys exhibit exceptionally high theoretical exothermic enthalpy (ΔH), surpassing 11606 J·g^(−1), which highlights their significant potential as innovative high-performance energetic structural materials.

关键词： Refractory high-entropy alloy Coherent microstructure Mechanical property Exothermic enthalpy

From a mononuclear FeL_(2)complex to a Fe_(4)L_(4)molecular square:Designed assembly and spin-crossover property

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Nano Research 2021年第2期14卷 398-403页

作者： Zhuo Wang Li-Peng Zhou Li-xuan cai Chong-Bin Tian Qing-Fu Sun State Key Laboratory of Structural Chemisty Fujian Institute of Rssearch on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

By introduction of a new Fe(L^(1))_(2)spin-crossover(SCO)unit into the polynuclear system,a nano-scale Fe4(L^(2))_(4)molecular square architecture is designed through coordination-directed self-assembly *** the mononuclear Fe(L^(1))_(2)and tetranuclear Fe4(L^(2))_(4)complexes have bee门structurally confirmed by 1H nuclear magnetic resonance(NMR),electrospray ionization time-of-flight mass spectrometry(ESI-TOF-MS),and temperature-dependent single crystal X-ray diffraction ***-temperature magnetic susceptibility measurements reveal the presence of an abrupt SCO behavior with a thermal hysteresis width of 4K for Fe(L^(1))_(2).By clear contrast,Fe4(L^(2))_(4)undergoes a gradual spin transition behavior with enlarged thermal hysteresis width and higher spin transition temperature.

关键词： spin-crossover compound molecular square iron coordination-directed self-assembly supram olecular chem istry

Supramolecular synthesis of coumarin derivatives catalyzed by a coordination-assembled cage in aqueous solution

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Science China Chemistry 2019年第6期62卷 713-718页

作者： Shao-Chuan Li Li-xuan cai Li-Peng Zhou Fang Guo Qing-Fu Sun State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences College of Chemistry Liaoning University

A self-assembled Pd_4L_2 cage is employed as a water-soluble molecular flask for the synthesis of functionalized coumarins from a series of salicylaldehyde derivatives and cyanoacetates/malononitrile. The catalytic reaction features mild aqueous conditions and broad substrate scope. Crystal structures of the host-guest complexes for two substrates and one analogous intermediate have been obtained, shedding light on the supramolecular reaction mechanism. Michaelis-Menten kinetic studies were performed in one typical case, revealing that the rate of product formation has been enhanced by over 23-fold in contrast to the background reaction without cage. Moreover, the same reaction catalyzed by a smaller Pd_6L_4 cage gives a mixture of products and much lower yields, suggesting that fine-tuning on the size and symmetry of the cages' cavity is crucial for their applications in supramolecular catalysis.

关键词： coordination-assembly cage encapsulation Knoevenagel condensation

Establishment and verification of a surgical prognostic model for cervical spinal cord injury without radiological abnormality

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Neural Regeneration Research 2019年第4期14卷 713-720页

作者： Jie Wang Shuai Guo xuan cai Jia-Wei Xu Hao-Peng Li Second Affiliated Hospital of Xi'an Jiaotong University Health Science Center Xi'an Jiaotong University

Some studies have suggested that early surgical treatment can effectively improve the prognosis of cervical spinal cord injury without radiological abnormality, but no research has focused on the development of a prognostic model of cervical spinal cord injury without radiological abnormality. This retrospective analysis included 43 patients with cervical spinal cord injury without radiological abnormality. Seven potential factors were assessed: age, sex, external force strength causing damage, duration of disease, degree of cervical spinal stenosis, Japanese Orthopaedic Association score, and physiological cervical curvature. A model was established using multiple binary logistic regression analysis. The model was evaluated by concordant profiling and the area under the receiver operating characteristic curve. Bootstrapping was used for internal validation. The prognostic model was as follows: logit(P) =-25.4545 + 21.2576 VALUE + 1.2160SCORE-3.4224 TIME, where VALUE refers to the Pavlov ratio indicating the extent of cervical spinal stenosis, SCORE refers to the Japanese Orthopaedic Association score(0–17) after the operation, and TIME refers to the disease duration(from injury to operation). The area under the receiver operating characteristic curve for all patients was 0.8941(95% confidence interval, 0.7930–0.9952). Three factors assessed in the predictive model were associated with patient outcomes: a great extent of cervical stenosis, a poor preoperative neurological status, and a long disease duration. These three factors could worsen patient outcomes. Moreover, the disease prognosis was considered good when logit(P) ≥-2.5105. Overall, the model displayed a certain clinical value. This study was approved by the Biomedical Ethics Committee of the Second Affiliated Hospital of Xi'an Jiaotong University, China(approval number: 2018063) on May 8, 2018.

关键词： nerve regeneration surgical prognostic model cervical spinal cord injury retrospective study multiple binary logistic regression analysis bootstrapping internal validation multiple imputations cervical spinal stenosis duration of disease Pavlov ratio neural regeneration

Fabrication and Characterization of Chitosan-Silk Fibroin/Hydroxyapatite Composites via in situ Precipitation for Bone Tissue Engineering

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Chinese Journal of Polymer Science 2015年第12期33卷 1661-1671页

作者： Jing-xiao Hu xuan cai Shao-bo Mo Li Chen Xin-yu Shen 童华 Key Laboratory of Analytical Chemistry for Biology and Medicine Ministry of Education College of Chemistry and Molecular Sciences Wuhan University

Homogeneous chitosan-silk fibroin/hydroxyapatite （CS-SF/HA） composites were prepared by in situ precipitation method driven by a multiple-order template. The morphology of the composites was investigated by scanning electron microscope （SEM） and transmission electron microscope （TEM）. The compositional analysis was carried out by X-ray diffraction analysis （XRD） and Fourier transformed infrared spectroscopy （FTIR）. The mechanical properties and biocompatibility of the composites were also determined. The results indicated that the inorganic particles of uniform size （50 nm） were well-dispersed among the CS-SF matrices. The compressive modulus of the CS-SF/HA composites was enhanced with the increasing amount of SF. The in vitro results suggested that the MC3T3-E1 osteoblast-like cells on CS-SF/HA composite disks displayed strong bonding and spreading, and the cell proliferation cultured on each composite disk increased throughout the culture period for up to 7 days. Especially, the samples with higher content of SF had much better biological properties. The evidences proved that the CS-SF/HA composites possessed excellent biocompatibility. By using the freeze-drying technique, hierarchical porous scaffolds with pores ranging from 50 μm to 200 μm were obtained. This work presented the advantages of in situ precipitation method to prepare the organic/inorganic composites, and a multiple-order template was introduced in the system to improve the properties of the composites by combining the merits of each organic template.

关键词： Composites In situ precipitation Biocompatibility Mechanical properties.

Complete colonic duplication presenting as hip fistula in an adult with pelvic malformation:A case report

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World Journal of Clinical Cases 2022年第30期10卷 11037-11043页

作者： xuan cai Jing-Tao Bi Zhi-Xue Zheng Ya-Qi Liu Department of General Surgery Beijing Jishuitan HospitalBeijing 100035China

BACKGROUND Alimentary tract duplication(ATD) is a rare congenital ***,a case of ATD with a complete colonic duplication isolated in the abdominal cavity with a fistula and multiple malformations is very *** characteristics show the variability of this disease and explain why it tends to be challenging to diagnose and *** SUMMARY A 25-year-old woman with a history of a fistula opening in her right hip since birth presented with the irregular discharge of foul fluid from the fistula and intermittent abdominal ***-enhanced computed tomography and magnetic resonance imaging findings revealed a duplicated tube isolated in her abdominal pelvic cavity along with a pelvic malformation and double *** foot radiographic examination showed pes *** surgery,the tube appeared to be an almost complete colonic structure and was verified to be connected to the *** of the involved tissue and fistula were removed,and the defect in the pelvic floor was closed by suturing after *** 8 mo,the postoperative follow-up has been *** ATD may be a differential diagnosis in sinus tract *** combined with open surgery is a viable treatment option.

关键词： Abdominal pain Colonic duplication Computed tomography Hip fistula Pelvic malformation Laparoscopy Case report

Combined phacoemulsification and anterior vitrectomy in a case of anterior megalophthalmos with open-angle glaucoma and high myopia

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International Journal of Ophthalmology(English edition) 2017年第7期10卷 1178-1180页

作者： cai-xuan Huang Xiao-Hui Zhao Yi-Qiao Xing Eye Center Renmin Hospital of Wuhan University

Dear Editor,I am ***-xuan Huang,from the Eye Center,Renmin Hospital of Wuhan University,Hubei Province,China.I write to present a case report of bilateral anterior megalophthalmos with open-angle glaucoma,which was tr... 详细信息

关键词： glaucoma bilateral Wuhan corneal Hubei write cataract capsular intraocular chamber

Peripapillary vessel density and retinal nerve fiber layer thickness changes in early diabetes retinopathy

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International Journal of Ophthalmology(English edition) 2022年第9期15卷 1488-1495页

作者： Xiang-Ning Wang xuan cai Ting-Ting Li Da Long Qiang Wu Department of Ophthalmology Shanghai Jiao Tong University Affiliated Sixth People’s HospitalShanghai 200233China Shanghai Key Laboratory of Diabetes Mellitus Shanghai 200233China

·AIM:To perform a quantitative analysis of the peripapillary vessel density(VD)and retinal nerve fiber layer(RNFL)thickness changes in patients with early stage of diabetic retinopathy(DR).·METHODS:In this case-control study,swept-source optical coherence tomography angiography(SS-OCTA)imaging was used to examine diabetic and age-matched healthy *** optic disc HD 6×6 mm^(2) blood flow imaging scan mode was *** software was used to measure the peripapillary VD,capillary vessel density(CVD),and RNLF in an optic nerve head(ONH)filed based on the Garway-Heath *** addition,the correlation between peripapillary VD,CVD,and RNFL was further investigated.·RESULTS:The cohort consisted of 32 healthy individuals and 72 patients with diabetes(34 eyes with no DR and 38 eyes with mild-moderate NPDR).Peripapillary VD decreased in the mild-moderate NPDR group compared to the control group in most regions(P<0.05).Peripapillary CVD and RNFL thickness were significantly lower in the mild-moderate NPDR group in the superior temporal(ST)quadrants(P=0.018.P=0.030).In the correlation analysis of each region,the RNFL thickness in the NS region was positively correlated with the peripapillary VD and CVD(r=0.233,P=0.05;r=0.288.P=0.015).In the TI region,the RNFL thickness was positively correlated with the peripapillary CVD(r=0.237,P=0.047).·CONCLUSION:The measurement based on the ONH topographic map may be helpful in detecting functional and structural impairments in *** peripapillary VD,CVD and RNFL decrease in early DR,and the RNFL thickness altered in association with the CVD or/and VD in some regions.

关键词： vessel density retinal nerve fiber layer diabetic retinopathy OCTA swept-source

Coordination-Assembled Lanthanide-Organic Ln3L3 Sandwiches or Ln4L4 Tetrahedron: Structural Transformation and Luminescence Modulation

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Chinese Journal of Chemistry 2019年第7期37卷 657-662页

作者： Shao-Jun Hu Xiao-Qing Guo Li-Peng Zhou Li-xuan cai Qing-Fu Sun State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences FuzhouFujian 350002 China College of Chemistry Fuzhou University Fuzhou Fujian 350108 ChinaState Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences FuzhouFujian 350002 China University of Chinese Academy of Sciences Beijing 100049 ChinaState Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences FuzhouFujian 350002 China

Photo-functional supramolecular lanthanides assemblies have shown great potential in the materials and biomedical *** new tri(tridentate) ligands (L3 and L4) highlighting small variation of the connection position to the central tridentate linkers have been designed,which leads to the emergent formation of either Ln3L3-type sandwich structures or Ln4L4-type tetrahedral ***,nonlinear enhancement of lanthanide luminescence based on the modulation of inter-ligand charge-transfer states has been revealed on the mix-ligand Ln3L3 *** results provide important guidance for structure-design and photoluminescence optimization of supramolecular lanthanide-organic assemblies.

关键词： Structural Transformation Luminescence Modulation