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Quick-scanning X-ray absorption fine structure beamline at SSRF

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Nuclear Science and Techniques 2024年第6期35卷 1-13页

作者： Yu Chen Qian Gao zheng Jiang Jiong li shuo Zhang Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

The layout and characteristics of the hard X-ray spectroscopy beamline(BL11B)at the Shanghai synchrotron radiation facility are described ***11B is a bending-magnet beamline dedicated to conventional and millisecond-scale quick-scanning X-ray absorption fine *** is equipped with a cylindrical collimating mirror,a double-crystal monochromator comprising Si(111)and Si(311),a channel-cut quick-scanning Si(111)monochromator,a toroidal focusing mirror,and a high harmonics rejection *** can provide 5-30 keV of X-rays with a photon flux of~5×10^(11)photons/s and an energy resolution of~1.31×10^(-4)at 10 *** performance of the beamline can satisfy the demands of users in the fields of catalysis,materials,and environmental *** paper presents an overview of the beamline design and a detailed description of its performance and capabilities.

关键词： Bending magnet beamline X-ray absorption fine structure Quick-scanning XAFS In situ Synchrotron radiation

Effective peroxydisulfate activation by CQDs-MnFe_(2)O_(4)@ZIF-8 catalyst for complementary degradation of bisphenol A by free radicals and non-radical pathways

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Chinese Chemical Letters 2024年第5期35卷 371-379页

作者： shuo li Xinran liu Yongjie zheng Jun Ma Shijie You Heshan zheng College of Chemistry and Chemical Engineering Qiqihar UniversityQiqihar 161006China State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

The present study reported fabrication of novel carbon quantum dots-MnFe_(2)O_(4)@ZIF-8(CQDs-MFO@ZIF-8)by using co-precipitation hydrothermal method for activation of peroxydisulfate(PDS)to degrade bisphenol A(BPA),one of important emerging organic pollutants in water ***-MFO@ZIF-8 served as a highly efficient thermal activated PDS catalyst with high catalytic degradation efficiency,reusability and *** catalyst achieved almost completely removal of 20.0 mg/L BPA within 5.0 min,and the degradation efficiency remained higher than 83%after 5 consecutive *** radicals(^(·)OH,SO_(4)^(·-)and^(·)O_(2)^(-))and non-free radicals((1)O_(2))were generated in the thermal PDS-activation system,in which singlet oxygen((1)O_(2))played a dominant role in the degradation of *** potential toxicity of BPA degradation intermediates was analyzed upon the culture of *** and Chlorella sorokiniana by using Ecological Structure-Activity Relationship Model(ECOSAR)*** catalytic performances of BPA degradation by CQDs-MFO@ZIF-8 were evaluated for treatment of different practical water samples to further verify the feasibility of practical *** study provides proof-in-concept demonstration of new nanomaterials for enhanced catalytic water decontamination.

关键词： Bisphenol A Degradation Peroxydisulfate ^(1)O_(2) Toxicity analysis

Quantification of the concrete freeze–thaw environment across the Qinghai–Tibet Plateau based on machine learning algorithms

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Journal of Mountain Science 2024年第1期21卷 322-334页

作者： QIN Yanhui MA Haoyuan ZHANG Lele YIN Jinshuai zheng Xionghui li shuo Department of Civil Engineering Qingdao University of TechnologyQingdao 266520China Department of Geography Qinghai Normal UniversityXining 810008China

The reasonable quantification of the concrete freezing environment on the Qinghai–Tibet Plateau(QTP) is the primary issue in frost resistant concrete design, which is one of the challenges that the QTP engineering managers should take into account. In this paper, we propose a more realistic method to calculate the number of concrete freeze–thaw cycles(NFTCs) on the QTP. The calculated results show that the NFTCs increase as the altitude of the meteorological station increases with the average NFTCs being 208.7. Four machine learning methods, i.e., the random forest(RF) model, generalized boosting method(GBM), generalized linear model(GLM), and generalized additive model(GAM), are used to fit the NFTCs. The root mean square error(RMSE) values of the RF, GBM, GLM, and GAM are 32.3, 4.3, 247.9, and 161.3, respectively. The R^(2) values of the RF, GBM, GLM, and GAM are 0.93, 0.99, 0.48, and 0.66, respectively. The GBM method performs the best compared to the other three methods, which was shown by the results of RMSE and R^(2) values. The quantitative results from the GBM method indicate that the lowest, medium, and highest NFTC values are distributed in the northern, central, and southern parts of the QTP, respectively. The annual NFTCs in the QTP region are mainly concentrated at 160 and above, and the average NFTCs is 200 across the QTP. Our results can provide scientific guidance and a theoretical basis for the freezing resistance design of concrete in various projects on the QTP.

关键词： Freeze–thaw cycles Quantification Machine learning algorithms Qinghai–Tibet Plateau Concrete

lin28 as a therapeutic target for central nervous system regeneration and repair

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Neural Regeneration Research 2024年第2期19卷 397-398页

作者： shuo Wang Shuxin li Shriners Hospitals Pediatric Research Center Department of Neural SciencesLewis Katz School of Medicine at Temple UniversityPhiladelphiaPAUSA

Axon disconnection in the central nervous system(CNS) usually causes signal transduction failure and severe functional deficits in patients with neurological disorders. Currently, there is no cure for patients with CNS axon injury and they usually suffer from life-long neurological defects(e.g., paralysis, loss of sensory function, and autonomic dysfunction) and life-threatening complications(e.g., autonomic dysreflexia).

关键词： paralysis therapeutic system

Porous organic cages as a novel platform for second harmonic generation

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Science China Chemistry 2024年第11期67卷 3669-3674页

作者： Feng Shui Yunqin Zhang Mao Yi Xiongli liu lin li shuo Zhang Yongshen zheng Yongtao Yao Qiao Zhao Baiyan li Xianhe Bu School of Materials Science and Engineering National Institute for Advanced Materials TKL of Metal and Molecule-Based Material Chemistry Nankai University National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology

Second harmonic generation(SHG) is one of the most extensively applied nonlinear optical phenomena. Compared to traditional inorganic SHG materials, organic SHG materials, including non-centrosymmetric small molecular crystals and organic polymers, have been extensively explored for SHG optics due to their advantageous properties, including high light-induced damage threshold, ultrafast response speed, high polarization ratio, wide transparency range, and elevated dielectric constant. However,in organic SHG materials, most small molecular crystals often show poor thermal stability(lication under high temperatures. On the other hand, the difficulty in the growth of large-size crystals as well as the disorderly array of chromospheres on polymer chains associated with organic polymers have hindered their widespread application in SHG due to the requirements of processability and ***, it is significantly necessary to develop novel organic SHG material with high thermal stability, large-size crystals,excellent processability, high homogeneity, and a well SHG effect. In the contribution, we developed herein porous organic cages(POCs) as a novel platform for SHG optics. Thanks to its inherent macromolecular composition and zero-dimensional discrete structures, POCs can not only solve the instability problem of small molecule crystals but also overcome the drawbacks in growing large-size crystals for organic polymer. The obtained two POCs with chiral asymmetric centers(CPOC-R-5 and CPOCS-7) display advantageous features for SHG optics including well SHG performance, large-size crystal(5 mm×3 mm×1 mm),high thermal stability(≥250 °C), wide transparency window(750–2,000 nm) and high polarization ratio(up to 94.5%). This work thus develops POCs as a new platform toward the construction of organic NLO materials with the potential application in sorts of SHG optics.

关键词： porous organic cages second harmonic generation novel SHG platform high thermal stability large-size single crystal

Freezing imaginarity of quantum states based onℓ_(1)-norm

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Chinese Physics B 2024年第10期33卷 166-175页

作者： shuo Han Bingke zheng Zhihua Guo School of Mathematics and Statistics Shaanxi Normal UniversityXi’an 710119China

We discuss freezing of quantum imaginarity based onℓ_(1)-*** properties about a quantity of imaginarity based onℓ_(1)-norm are *** a qubit(2-dimensional)system,we characterize the structure of real quantum operations that allow for freezing the quantity of imaginarity of any ***,we characterize the structure of local real operations which can freeze the quantity of imaginarity of a class of N-qubit quantum states.

关键词： imaginarity freezing ℓ_(1)-norm real operation

Hole cleaning evaluation and installation spacing optimization of cuttings bed remover in extended-reach drilling

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Petroleum Science 2024年第3期21卷 2005-2022页

作者： shuo Peng Wen-Jun Huang De-li Gao MOE Key Laboratory of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBeijing102249China

In extended-reach or long-horizontal drilling,cuttings usually deposit at the bottom of the *** cuttings accumulate to a certain thickness,complex problems such as excessive torque and drag,tubing buckling,and pipe stuck probably occur,which results in a lot of non-productive time and remedial *** bed remover can efficiently destroy deposited cuttings in time through hydraulic and mechanical stirring *** paper aims to build a method for hole cleaning evaluation and installation spacing optimization of cuttings bed remover to improve the wellbore cleaning ***,a Computational Fluid Dynamics approach with Eulerian—Eulerian multiphase model was utilized to investigate the mechanism of cuttings transportation,and a new type of cuttings bed remover was ***,an evaluation method of hole cleaning effect of remover was *** that,the effects of several drilling parameters on hole cleaning including flow rate of drilling fluid,rotational speed of drillpipe,rate of penetration,wellbore size,rheological property of drilling fluid,and remover eccentricity on the performance of cuttings bed remover were *** results demonstrate that the new type of remover with streamline blade performs better than conventional *** efficiency of hole cleaning is greatly improved by increasing the rotational speed of drillpipe,flow rate of drilling fluid,remover eccentricity,and 6 rpm Fann dial reading for drilling *** higher rate of penetration and large wellbore size result in worse hole *** findings can serve as an important guide for the structure optimization design of cuttings bed remover and installation spacing of removers.

关键词： Extended-reach drlling Drilling hydraulics Cuttings transport Hole cleaning Cuttings bed remover

Frequency and size change of ice–snow avalanches in the central Himalaya:A case from the Annapurna Ⅱ glacier

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Advances in Climate Change Research 2024年第3期15卷 464-475页

作者： Yao li Yi-Fei CUI Jian-Sheng HAO zheng-Tao ZHANG Hao WANG Jian GUO shuo-Fan WANG State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Hydrosphere Sciences of the Ministry of Water Resources Beijing 100084China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of National Safety and Emergency Management Beijing Normal UniversityBeijing 100875China Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Glaciers have retreated and shrunk in High Mountain Asia since the mid-20th century because of global warming,leading to glacier instability and hazardous iceesnow ***,the complex relationship between iceesnow avalanches and factors such as climate and potential triggers are difficult to understand because of the lack of observational ***,we addressed iceesnow avalanches on the Annapurna Ⅱ glacier in Nepal,Central *** constructed an iceesnow avalanche history using long-term multi-source remote sensing images(1988-2021)and mapped the velocity fields of glaciers using cross-correlation analysis on SAR and optical ***,we investigated the impact of climate change and earthquakes on the frequency and size of iceesnow *** results demonstrate that the frequency of iceesnow avalanches has increased from 10 in 1988 to 27 in 2020,but the average area of iceesnow avalanche deposits has decreased by approximately 70%,from 3.4×10^(5) m^(2) in 1988 to 1.2×10^(5) m^(2) in *** evolutionary characteristic of ice avalanches is linked to the impact of glacier retreat(reduction in ice material supply)and increased activity under climate *** glacier movement velocity controls the size of iceesnow avalanches and can be set as an indicator for iceesnow avalanche *** the Annapurna Ⅱ glacier,an iceesnow avalanche occurred when the glacier velocities were greater than 1.5 m d^(-1).These results offer insights into iceesnow avalanche risk assessment and prediction in high-mountain areas,particularly in regions characterised by dense glacier distribution.

关键词： Iceesnow avalanche Glacier instability Climate change Central Himalaya Remote sensing

Biomimetic Recognition-Based Bioorthogonal Host-Guest Pairs for Cell Targeting and Tissue Imaging in living Animals

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CCS Chemistry 2022年第6期4卷 1977-1989页

作者： Yan-Long Ma Chen Sun Zeshun li Ziyi Wang Jianwen Wei Qian Cheng li-shuo zheng Xiao-Yong Chang Kai li Ruibing Wang Wei Jiang Shenzhen Grubbs Institute Guangdong Provincial Key Laboratory of Catalysisand Department of ChemistrySouthern University of Science and TechnologyShenzhen 518055 State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical ScienceMoE Frontiers Science Center for Precision OncologyUniversity of MacaoTaipaMacao 999078 Department of Biomedical Engineering Southern University of Science and TechnologyShenzhen 518055

Bioconjugation methods offer very important tools in studying biological *** host-guest pairs provide an alternative and complementary conjugation method to bioorthogonal reactions and biological association ***,macrocyclic hosts that can be used for in situ capture are limited and often rely on extremely high binding ***,we report an alternative bioorthogonal host-guest pair that relies on highly selective molecular recognition in *** host,namely amide naphthotube,possesses a biomimetic cavity with inward-directing hydrogen bonding sites and shows selective and strong binding to the guest(2-phenyl pyrimidine)even in biological *** anchoring the tetraphenyl ethylene-modi fied hosts to cell surfaces,the bioorthogonal host-guest pair can be applied in cell surface recognition,cell-cell interactions,and tissue imaging in *** bioorthogonality is originated from the high binding selectivity of the biomimetic macrocyclic host,which is different from other known host-guest pairs that have been applied in biological *** research provides a new noncovalent bioconjugation tool and a new concept for designing bioorthogonal host-guest pairs for biological applications.

关键词： cell targeting tissue imaging bioconjugation bioorthogonal host-guest pair naphthotube