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Is the X-ray pulsating companion of HD 49798 a possible type Ia supernova progenitor?

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Research in Astronomy and Astrophysics 2015年第11期15卷 1813-1822页

作者： Dong-Dong Liu Wei-Hong Zhou cheng-yuan wu Bo Wang Yunnan Observatories Chinese Academy of Sciences Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences University of Chinese Academy of Sciences National Astronomical Observatories Chinese Academy of Sciences Yunnan Minzu University

HD 49798（a hydrogen depleted subdwarf O6 star） with its massive white dwarf（WD） companion has been suggested to be a progenitor candidate of a type Ia supernova（SN Ia）. However, it is still uncertain whether the companion of HD 49798 is a carbon-oxygen（CO） WD or an oxygen-neon（ONe） WD. A CO WD will explode as an SN Ia when its mass grows and approaches the Chandrasekhar limit, but the outcome of an accreting ONe WD is likely to be a neutron star. We generated a series of Monte Carlo calculations that incorperate binary population synthesis to simulate the formation of ONe WD ＋ He star systems. We found that there is almost no orbital period as large as HD 49798 with its WD companion in these ONe WD ＋ He star systems based on our simulations, which means that the companion of HD 49798 might not be an ONe WD. We suggest that the companion of HD 49798 is most likely a CO WD, which can be expected to increase its mass to the Chandrasekhar limit by accreting He-rich material from HD 49798. Thus, HD 49798 and its companion may produce an SN Ia as a result of its future evolution.

关键词： progenitor primordial likely uncertain depleted ejection neutron orbital unstable dwarf

Preparation of modified SiO_2 colloidal spheres with succinic acid and the assembly of colloidal crystals

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Chinese Science Bulletin 2007年第4期52卷 461-466页

作者： FANG Jun WANG XiuFeng WANG LieSong cheng Bing wu yuan-Ting ZHU WanLin School of Materials Science and Engineering Shaanxi University of Science and Technology Xi'an 712081 China

SiO2 colloidal spheres were synthesized by St-ber method. In order to enhance surface charge of the SiO2 spheres, they were modified with succinic acid. Scanning electron microscope (SEM) shows that the average size of modified SiO2 spheres is 473 nm, and its distribution standard deviation is less than 5%; Fourier-transform infrared spectra (FT-IR) and X-ray photoelectron spectrometer (XPS) results indicate that one end of succinic acid is chemically bonded to the SiO2 spheres through esterification; Zeta potential of the modified SiO2 spheres in water solution is improved from -53.72 to -67.46 mV, and surface charge density of the modified SiO2 spheres is enhanced from 0.19 to 0.94 μC/cm2. SiO2 colloidal crystal was fabricated from aqueous colloidal solution by the vertical deposition method at 40℃ and 60% relative humidity. SEM images show that the sample of SiO2 colloidal crystal is face-centered cubic (fcc) structure with its (111) planes parallel to the substrate. Transmission measurement shows the existence of photonic band gap at 1047 nm.

关键词：琥珀酸二氧化硅胶质球胶质晶体光学晶体制备表面电荷密度

Fluorescence emission from excited molecular ions in intense femtosecond laser fields

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Frontiers of physics 2013年第1期8卷 34-38页

作者： Yun-Chen Wang cheng-Yin wu yuan-Xing Liu Shao-Hua Xu Qi-Huang Gong State Key Laboratory for Mesoscopic Physics Department of Physics Peking University Beijing 100871 China

Strong fluorescence emissions were observed for nitrogen, carbon monoxide, and carbon dioxide molecules in intense femtosecond laser fields. These emissions can be assigned to the transitions of the molecular ions from the excited electronic states to the ground electronic states. The formation mechanisms were discussed and the lifetimes were measured for these excited molecular ions in intense laser fields.

关键词： tunneling ionization molecular orbital fluorescence

The C/O ratio of He-accreting carbon-oxygen white dwarfs and type Ia supernovae

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Research in Astronomy and Astrophysics 2020年第1期20卷 19-26页

作者： Xiao Cui Bo Wang cheng-yuan wu Xiang-Cun Meng Zhan-Wen Han Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China University of the Chinese Academy of Sciences Beijing 100049China

Type Ia supernovae(SNe Ia)are thermonuclear explosions of carbon-oxygen white dwarfs(CO WDs),and are believed to be excellent cosmological distance indicators due to their high luminosity and remarkable ***,there exists a diversity among SNe Ia,and a poor understanding of the diversity hampers the improvement of the accuracy of cosmological distance *** variations of the ratios of carbon to oxygen(C/O)of WDs at explosion are suggested to contribute to the *** the canonical model of SNe Ia,a CO WD accretes matter from its companion and increases its mass till the Chandrasekhar mass limit when the WD *** this work,we studied the C/O ratio for accreting CO *** the stellar evolution code MESA,we simulated the accretion of He-rich material onto CO WDs with different initial WD masses and different mass accretion *** found that the C/O ratio varies for different *** C/O ratio of He-accreting CO WDs at explosion increases with a decreasing initial WD mass or a decreasing accretion *** various C/O ratios may,therefore,contribute to the diversity of SNe Ia.

关键词： stars:evolution supernovae:general white dwarfs

THREE-DIMENSIONAL COMPUTED TOMOGRAPHY-GUIDED RADIOFREQUENCY TRIGEMINAL RHIZOTOMY FOR TREATMENT OF IDIOPATHIC TRIGEMINAL NEURALGIA

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Chinese Medical Sciences Journal 2005年第3期20卷 206-209页

作者： Meng Liu cheng-yuan wu Yu-guang Liu Hong-wei Wang Fan-gangMeng Department of Neurosurgery Qilu Hospital Shandong University Jinan 250012

Objective To evaluate the effectiveness of three-dimensional computed tomography （3D-CT） guided radiofi＇equency trigeminal rhizotomy （RF-TR） in treatment of idiopathic trigeminal neuralgia （1TN）. Methods From 1999 to 2001, 18 patients with ITN were treated with percutaneous controlled RF-TR. Intraoperative 3D-CT scanning was performed to guide the trajectory of the puncture. After correction of the needle tip according to the CT scans and stimulation effects, 2 to 5 lesions were made for a duration of 60-90 seconds at a temperature of 60℃ to 75℃ depending on the pain distribution and the age of patient. The needles located in foramen ovale. Pain alleviated immediately with no serious complication in all patients. The patients were followed up for an average of 31.5 months （range 24-41 months）. Acute pain relief was experienced by 17 patients after the procedure, reaching an initial success rate of 94.4%. Early （〈 6 months） pain recurrence was observed in 2 patients （11.1%）, whereas late （〉 6 months） recurrence was reported in 3 patients （16.7%）. Thirteen patients had complete pain control, with no need for medication thereafter. Five cases experienced partial pain relief, but required medication at a lower dose than in the preoperative period. Conclusion 3D-CT foramen ovale locations can raise the successful rate of puncture, enhance the safety, and reduce the incidence rate of complication.

关键词： trigeminal neuralgia radiofrequency trigeminal rhizotomy three-dimensional computed tomograhpy

“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage

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Nano-Micro Letters 2025年第1期17卷 348-360页

作者： Yan Zhao Qiang yuan Liting Yang Guisheng Liang Yifeng cheng Limin wu Chunfu Lin Renchao Che College of Physics Donghua UniversityShanghai 201620People’s Republic of China School of Materials Science and Engineering Institute of Materials for Energy and EnvironmentQingdao UniversityQingdao 266071People’s Republic of China Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China Inner Mongolia University Hohhot 010021People’s Republic of China

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte ***,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term ***,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical *** Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O *** superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

关键词： NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization

The compound(E)-2-(3,4-dihydroxystyryl)-3-hydroxy-4H-pyran-4-one alleviates neuroinflammation and cognitive impairment in a mouse model of Alzheimer's disease

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Neural Regeneration Research 2025年第11期20卷 3330-3344页

作者： Xueyan Liu Wei wu Xuejuan Li chengyan Wang Ke Chai Fanru yuan Huijuan Zheng Yuxing Yao Chenlu Li Zu-cheng Ye Daijun Zha Department of Medicinal Chemistry School of PharmacyFujian Medical UniversityFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Institute of Laboratory Animal Center Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurosurgery Neurosurgery Research InstituteThe First Affiliated HospitalFujian Medical UniversityFuzhouFujian ProvinceChina Department of Hyperbaric Oxygen National Regional Medical CenterBinhai Campus of the First Affiliated HospitalFujian Medical UniversityFuzhouFujian ProvinceChina

Previous studies have shown that the compound(E)-2-(3,4-dihydroxystyryl)-3-hydroxy-4H-pyran-4-one(D30),a pyromeconic acid derivative,possesses antioxidant and anti-inflammatory properties,inhibits amyloid-β aggregation,and alleviates scopolamine-induced cognitive impairment,similar to the phase Ⅲ clinical drug *** this study,we established a mouse model of Alzheimer's disease via intracerebroventricular injection of fibrillar amyloid-β to investigate the effect of D30 on fibrillar amyloid-β-induced *** results showed that D30 alleviated fibrillar amyloid-β-induced cognitive impairment,promoted fibrillar amyloid-β clearance from the hippocampus and cortex,suppressed oxidative stress,and inhibited activation of microglia and astrocytes.D30 also reversed the fibrillar amyloid-β-induced loss of dendritic spines and synaptic protein ***,we demonstrated that exogenous fibrillar amyloid-βintroduced by intracerebroventricular injection greatly increased galectin-3 expression levels in the brain,and this increase was blocked by *** the role of D30 in clearing amyloid-β,inhibiting neuroinflammation,protecting synapses,and improving cognition,this study highlights the potential of galectin-3 as a promising treatment target for patients with Alzheimer's disease.

关键词： Alzheimer's disease amyloid-β astrocyte cognitive impairment D30 dendritic spines galectin-3 microglia neuroinflammation neuron

A mild, configurable, flexible CoNi-LDH（v）/Zn battery based on H-vacancy-induced reversible Zn2+ intercalation

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Journal of Energy Chemistry 2025年第1期100卷 498-508页

作者： Xinyue cheng Dingsheng wu Hao Gao Qingqing Wang Pengfei Lv Sam S.Yoon Qufu Wei Key Laboratory of Eco-textiles Ministry of Education Jiangnan University School of Mechanical Engineering Korea University

Flexible Zn-based batteries have attracted increasing research interest as essential components of wearable energy storage ***,the advancement of flexible aqueous Zn-based batteries based on Co-Ni layered double hydroxide （CoNi-LDH） as the cathode material is hampered by their poor cycling stability and the corrosiveness of alkaline ***,CoNi-LDH nanosheets enriched with H vacancies (CoNi-LDH（v）) were constructed on a flexible carbon cloth （CC） substrate via electrochemical deposition and *** Zn-based battery comprising CoNi-LDH（v）@CC as the cathode exhibited highly reversible conversion reactions and stable operation in 3 M ZnSO4electrolyte （pH=4）.The battery delivered an excellent specific capacity (225 mA h g-1,0.26 mA h cm-2),acceptable cycling stability（53.9%,900 cycles）,and high discharging *** abundant H vacancies served as active sites for the reversible intercalation of Zn2+and the extravasation of NO3-generated channels and space for Zn2+transport and storage,together enabling an excellent Zn2+storage ***,a sandwich-structured solid-state CoNi-LDH（v）@CC//Zn@CC battery was fabricated and was found to exhibit a noteworthy electrochemical performance and mechanical *** a proof of concept,the unencapsulated battery powered a digital watch under various deformation conditions and operated stably for 80 ***,the flexible battery displayed outstanding customizability,maintaining an open-circuit voltage of 1.42 V even after being cut *** proposed engineering strategy contributes to the realization of textiles with truly wearable energy-storage devices.

关键词： CoNi/Zn battery H vacancies Mild aqueous electrolyte Tailorable battery Wearable energy storage device

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陇南铁矿石中全铁量的测定

甘肃冶金 2011年第4期33卷 80-81页

作者：程武元甘肃省有色金属地质勘查局中心实验室甘肃兰州730046

本法采用硫磷酸分解,在盐酸介质中,用二氯化锡将三价铁还原至二价,再用二氯化汞除去过量的二氯化锡,以二苯胺磺酸钠作指示剂,用重铬酸钾标准溶液滴定测全铁量。本法样品溶解完全,溶解速度快,分析精确度高。

关键词：铁矿石全铁量测定