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Adsorbate-driven dynamic active sites in stannosilicate zeolites

Fundamental Research 2025年第1期5卷 174-182页

作者： Yi, Xianfeng Xiao, Yao Xia, Changjiu Liu, Fengqing Liu, Yujia Hui, Yu Yu, Xin Qin, Yucai Chen, Wei Liu, Zhiqiang Song, Lijuan Zheng, Anmin State Key laboratory of magnetic resonance and Atomic and Molecular Physics National Center for Magnetic Resonance in Wuhan Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and Technology Chinese Academy of Sciences Wuhan 430071 China University of Chinese Academy of Sciences Beijing 100049 China State Key laboratory of Catalytic Materials and Reaction Engineering Research Institute of Petroleum Processing SINOPEC Beijing 100083 China Key laboratory of Petrochemical Catalytic Science and Technology Liaoning Petrochemical University Fushun 113001 China

Elucidating the nature of the active sites in heterogeneous catalysts is fundamental for understanding their reactivity and catalytic performances. Although stannosilicate zeolites have tremendous application potential for catalyzing biomass-related compounds in aqueous media, the detailed local structures and features of the real active sites and their possible structural variations under reaction conditions are poorly understood to date. In this study, a dynamic transformation of framework Sn−O−Si sites to Sn−OH/Si−OH pairs and subsequently a pseudo-Brønsted acid in stannosilicate zeolites upon molecular adsorption, which is analogous to various adsorbates/reactants under working conditions, was identified by solid-state nuclear magnetic resonance (NMR) spectroscopy for the first time, which challenges the widespread assumption that the active center structures remain rigid/stable during the catalytic process. These results provide new comprehensive insights for the fundamental understanding of the dynamic and flexible active centers and involved reaction mechanisms of novel zeolite catalysts with heterometal atoms, such as Sn, Ti, and Zr. © 2023

关键词： Dynamic active sites Pseudo-Brønsted acid Reaction conditions Solid-state NMR Stannosilicate zeolites

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Accelerating Hartree-Fock Self-consistent Field Calculation on C86/DCU Heterogenous Computing Platform

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Chinese Journal of Chemical Physics 2025年第1期38卷 81-94,I0056页

作者： Ji Qi Huimin Zhang Dezun Shan Minghui Yang State Key laboratory of magnetic resonance Spectroscopy and imaging Wuhan Institute of Physics and MathematicsInnovation Academy of Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Wuhan National laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430000China

In this study,we investigate the ef-ficacy of a hybrid parallel algo-rithm aiming at enhancing the speed of evaluation of two-electron repulsion integrals(ERI)and Fock matrix generation on the Hygon C86/DCU(deep computing unit)heterogeneous computing *** hybrid parallel schemes are assessed using a range of model systems,including those with up to 1200 atoms and 10000 basis *** findings of our research reveal that,during Hartree-Fock(HF)calculations,a single DCU ex-hibits 33.6 speedups over 32 C86 CPU *** with the efficiency of Wuhan Electronic Structure Package on Intel X86 and NVIDIA A100 computing platform,the Hygon platform exhibits good cost-effective-ness,showing great potential in quantum chemistry calculation and other high-performance scientific computations.

关键词： Quantum chemistry Self-consistent field Hartree-Fock Electron repulsion inte-grals Heterogenous parallel computing C86/deep computing unit

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Triggering highly nonlinear responses in 229 Th nuclei with an intense laser

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Nuclear Science and Techniques 2025年第2期36卷 1-4页

作者： Xiao-Jun Liu State Key laboratory of magnetic resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China

In a recent paper published in ***.133,152503(2024),***,***,and *** predicted that modern intense lasers can induce highly nonlinear responses in the 229 Th nucleus for the first time,which is an astonishing effect of light-nucleus *** phenomenon is underpinned by two key factors:(1)the presence of a very low-lying nuclear excited state and(2)a nuclear hyperfine mixing effect that significantly enhances light-nucleus *** resulting highly nonlinear responses facilitate efficient nuclear excitation and enable coherent light emission from the nucleus,resulting in high harmonic generation.229 Th presents a promising platform for advancements in both laser-nuclear physics and nuclear clock *** pioneering work by Zhang et *** a new frontier in light-matter interactions.

关键词： nonlinear intense frontier

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Relativistic hyperpolarizabilities of atomic H,Li,and Be^(+)systems

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Chinese Physics B 2025年第2期34卷 230-239页

作者： Shan-Shan Lu Hong-Yuan Zheng Zong-Chao Yan James F.Babb Li-Yan Tang State Key laboratory of magnetic resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Department of Physics University of New BrunswickFrederictonNew BrunswickE3B 5A3Canada ITAMP Center for Astrophysics|Harvard&Smithsonian60 Garden St.CambridgeMA 02138USA

For atoms in external electric fields,the hyperpolarizabilities are the coefficients describing the nonlinear interactions contributing to the induced energies at the fourth power of the applied electric *** evaluations of these coefficients for various systems are crucial for improving precision in advanced atom-based optical lattice clocks and for estimating field-induced effects in atoms for quantum information ***,there is a notable scarcity of research on atomic hyperpolarizabilities,especially in the relativistic *** work addresses this gap by establishing a novel set of alternative formulas for the hyperpolarizability based on the fourth-order perturbation *** formulas offer a more reasonable regrouping of scalar and tensor components compared to previous formulas,thereby enhancing their correctness and *** validate our formulas,we perform the calculations for the ground and low-lying excited pure states of few-electron atoms H,Li,and Be^(+).The highly accurate results obtained for the H atom could serve as benchmarks for further development of other theoretical methods.

关键词： hyperpolarizabilities Stark effect fourth-order perturbation few-electron atoms

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Perfusion computed tomography in colorectal cancer:Protocols,clinical applications and emerging trends

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World Journal of Gastroenterology 2009年第26期15卷 3228-3231页

作者： Prasanna Ghimire Department of magnetic resonance imaging Zhongnan HospitalWuhan University

Perfusion computed tomography (CT) has emerged as a novel functional imaging technique with gradually increasing importance in the management of colorectal cancer (CRC).By providing the functional tumor microvasculature,it also helps the assessment of therapeutic response of anti-angiogenic drugs as it may reflect tumor *** CT has been applied in clinical practice to delineate inflammatory or neoplastic lymph nodes irrespective of their size,identify micro-metastases and to predict metastases in advance of their *** is of increasing significance for preoperative adjuvant therapies and avoidance of unnecessary *** controversies regarding the techniques employed,its validity and reproducibility,it can be advantageous in the management of CRCs in which the prognosis is dependent on preoperative *** recent advances in the perfusion CT techniques,and incorporation to other modalities like positron emission tomography,perfusion CT will be a novel tool in the overall management of *** article aims at reviewing the existing clinical applications and recent advances of perfusion CT with a reference to future development in the management of CRCs.

关键词： Colorectal cancers Perfusion computed tomography Angiogenesis Neovascularization Micrometastases

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Light-activated tautomeric transition enhanced buried heterointerface for highly efficient and ultraviolet robust perovskite solar cells

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Science China Chemistry 2025年第2期68卷 723-732页

作者： Sheng Jiang Shaobing Xiong Shuaifei Mao Yefan Zhang Dongyang Zhao Xiaomeng You Vladimir Gaishun Dmitry Kovalenk Qinye Bao School of Physics and Electronic Science East China Normal UniversityShanghai 200241China Shanghai Frontiers Science Research Base of Intelligent Optoelectronics and Perception Institute of OptoelectronicsFudan UniversityShanghai 200433China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123China Shanghai Key laboratory of magnetic resonance East China Normal UniversityShanghai 200241China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Department of Physics and Information Technologies Francisk Skorina Gomel State UniversityGomel 246028Belarus

The buried heterointerface of perovskite solar cells(PSCs)suffers from serious nonradiative recombination and ultraviolet(UV)light stress,relentlessly limiting further increase in their power conversion efficiency and operational ***,we develop an emerging strategy of incorporating a thin UV-activated tautomeric transition layer onto underlying charge transport layer and then depositing perovskite layer to construct an efficient hole-selective buried *** is revealed that the UV-activated tautomeric transition interlayer not only improves upper perovskite crystallinity,diminishes thermionic loss for collecting hole and passivates defect site at such buried contact that significantly promote charge transport and suppress nonradiative recombination,but also effectively protects adjacent perovskite from UV degradation through“UV sunscreen”*** a result,we report a remarkably enhanced efficiency of 24.76%compared to 22.02%of the control *** importantly,the achieved high-efficiency PSC features excellent resistance against UV radiation at 365 nm of 100 and 850 mW cm^(−2),which are approximately 21 and 184 times of UV flux(4.6 mW cm^(−2))under AM 1.5G solar *** work provides a promising approach of strengthening buried heterointerface for simultaneous realization of highly efficient and UV robust PSCs.

关键词： buried heterointerface energetics nonradiative recombination ultraviolet resistance perovskite solar cell

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Differential study of DCE-MRI parameters in spinal metastatic tumors, brucellar spondylitis and spinal tuberculosis

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Chinese Journal of Cancer Research 2018年第4期30卷 425-431页

作者： Pengfei Qiao Pengfei Zhao Yang Gao Yuzhen Bai Guangming Niu Department of magnetic resonance imaging the Affiliated Hospital of Inner Mongolia Medical University

Objective： In the present study, spinal metastatic tumors, brucellar spondylitis and spinal tuberculosis werequantitatively analyzed using dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI） to assess thevalue of DCE-MRI in the differential diagnosis of these ***： Patients with brucellar spondylitis, spinal tuberculosis or a spinal metastatic tumor （30 cases of each）received conventional MRI and DCE-MRI examination. The volume transfer constant （Ktrans）, rate constant （Kep）,extravascular extracellular volume fraction （Ve） and plasma volume fraction （Vp） of the diseased vertebral bodieswere measured on the perfusion parameter map, and the differences in these parameters between the patients ***： For pathological vertebrae in cases of spinal metastatic tumor, brucellar spondylitis and spinaltuberculosis, respectively, the Ktrans values （median ＋ quartile pitch） were 0.989±0.014, 0.720±0.011 and0.317±0.005 min-1; the Kep values were 2.898±0.055, 1.327±0.017 and 0.748±0.006 min-1; the Ve values were0.339±0.008, 0.542±0.013 and 0.428±0.018; the Vp values were 0.048±0.008, 0.035±0.004 and 0.028±0.009; thecorresponding H values were 50.25 （for Ktrans）, 52.47 （for Kep）, 48.33 （for Ve） and 46.56 （for Vp）, and all differenceswere statistically significant （two-sided P〈0.05）.Conclusions： The quantitative analysis of DCE-MRI has a certain value in the differential diagnosis of spinalmetastatic tumor, brucellar spondylitis and spinal tuberculosis.

关键词： Differential diagnosis dynamic contrast enhanced MRI spinal tuberculosis spinal metastatic tumor brucellar spondylitis

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Storage time affects the level and diagnostic efficacy of plasma biomarkers for neurodegenerative diseases

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Neural Regeneration Research 2025年第8期20卷 2373-2381页

作者： Lifang Zhao Mingkai Zhang Qimeng Li Xuemin Wang Jie Lu Ying Han Yanning Cai Department of Clinical Biobank Xuanwu HospitalCapital Medical UniversityBeijingChina Beijing Geriatric Medical Research Center BeijingChina Department of Neurology Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Radiology and Nuclear Medicine Xuanwu HospitalCapital Medical UniversityBeijingChina Beijing Key laboratory of magnetic resonance imaging and Brain Informatics BeijingChina Key laboratory of Neurodegenerative diseases Ministry of EducationBeijingChina School of Biomedical Engineering Hainan UniversityHaikouHainan ProvinceChina Center of Alzheimer’s Disease Beijing Institute for Brain DisordersBeijingChina National Clinical Research Center for Geriatric Diseases BeijingChina Institute of Biomedical Engineering Shenzhen Bay LaboratoryGaoke Innovation CenterShenzhenGuangdong ProvinceChina Department of Neurobiology Xuanwu HospitalCapital Medical UniversityBeijingChina

Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative ***,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°*** aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large *** samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline *** samples were stored at-80°C for up to 6 years before being used in this *** results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage ***,the level of total tau showed a negative correlation with sample storage ***,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage *** was not observed in individuals with cognitive ***,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage ***,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's ***,in cohort studies,it is important to consider the impact of storage time on the overall results.

关键词： Alzheimer’s disease amyloid-β diagnostic ability glial fibrillary acidic protein neurodegeneration neurofilament light chain plasma biomarkers single molecule array storage time tau

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Ultrastable Nd:YAG 1064-nm lasers with 2.1×10-16 frequency stability based on a field-programmable gate array frequency-locked system

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Chinese Optics Letters 2025年第1期 72-76页

作者：李振千芦宗昱万凌风茹媛陈李生李刘锋 Innovation Academy for Precision Measurement Science and Technology Chinese Academy of Sciences University of Chinese Academy of Sciences State Key laboratory of magnetic resonance and Atomic and Molecular Physics

Ultrastable continuous-wave lasers are one of the important elements for space-based gravitational wave detection. Here we present a Pound–Drever–Hall laser frequency-locked system based on a field-programmable gate array, demonstrating its potential to achieve 10-16levels of frequency stability for space applications. The system is employed to lock a spacequalified 1064-nm neodymium-doped yttrium aluminum garnet laser to a laboratory-operated 20-cm ultrastable optical cavity. Major noise contributors are identified as laser intensity fluctuation and residual amplitude modulation. The heterodyne beat measurement shows that the frequency noise spectral density of a single laser is reduced to 2.5 Hz/√Hz at a Fourier frequency of 1 m Hz, and the frequency instability is 2.1 × 10-16at 1 s and remains below 3.5 × 10-16up to 6000 s.

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Therapeutic effect and mechanism of breviscapine on cisplatin-induced nephrotoxicity in mice

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Asian Pacific Journal of Tropical Medicine 2015年第10期8卷 853-857页

作者： Xiao-Yu Lou Jing-Liang Cheng Bo Zhang Department of magnetic resonance imaging the First Affiliated Hospital of Zhengzhou University Department of magnetic resonance imaging the First Affiliated Hospital of Luohe Medical College Department of Ultrasound in Medicine East HospitalTongji University School of Medicine

Objective:To observe the protective effect of breviscapineon mice with cisplatin-induced ***:Mice were given a single injection of cisplalin(8 mg/kg,up.);then,breviscapine was given to mice at 25 mg/kg and 50 mg/kg doses,respectively,once a day for seven *** tissue structure was observed after animals were *** urea nitrogen(BUN),serum creatinine(Scr),lipid peroxide(MDA) and superoxide dismutase(SOD) serum levels were detected;and MDA,glutathione peroxidase,and SOD levels in the renal cortex were ***:Compared with the blank control group(BCG),the kidney pathological damage of mice in the model control group(MCG) was more *** applying different doses of breviscapine,different degrees of renal injury improvement *** with the BCG,the serum levels of Scr and BUN in the MCG increased to(89.92±6.78) μmoL/L and(15.32±4.53) mmoL/*** differences were statistical significant(P<0.01).Compared with the MCG,the serum levels of Scr and BUN in the Bre low-dose groups and Bre high-dose groups decreased significantly(P<0.05).Compared with the BCG,the MDA levels in serum and in the renal cortex in the MCG significantly increased,while the SOD levels significantly *** the differences were statistically significant(P<0.01).In the Bre low-dose groups and Bre high-dose groups,MDA levels in serum and in the renal cortex significantly decreased,while SOD and glutathione peroxidase levels in the renal cortex significantly increased,compared with the MCG;and the differences were statistically significant(P<0.05).Conclusions:Breviscapine can reduce cisplatin induced renal toxicity in mice and it's possible through inhibition of renal tubule cell lipid peroxidation and reduces the nephrotoxicity of cisplatin.

关键词： Cisplatin Renal injury Breviscapine Protective eff

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