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Application of three-dimensional electron diffraction in structure determination of zeolites

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结构化学 2024年第4期43卷 39-47页

作者： Yuhang li Yang ling Yanhang ma School of Physical Science and Technology & Shanghai Key Laboratory of High-resolution Electron Microscopy ShanghaiTech UniversityShanghai201210China

Zeolites have received great attention due to their wide applications in various fields such as catalysis,adsorp-tion/separation,ion exchange,*** the atomic crystal structure of zeolites is crucial to understanding their functions and exploring their *** to the difficulty of synthesizing large single crystals,the structures of many zeolites cannot be solved using conventional single-crystal X-ray diffraction(SCXRD)***-dimensional electron diffraction(3D ED)has witnessed rapid development during the past decade and has shown its powerful ability in the structure determination of *** this review,we will briefly introduce the history of 3D ED and summarize recent advances in the application of 3D ED for the analysis of zeolite structures,along with several typical examples in this research field.

关键词： Electron diffraction Three-dimensional electron diffraction Zeolite Structure solution Electron crystallography

Aptasensing biosynthesized phosphatidylserine with a AuNPs nanozyme-based colorimetric aptasensor

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Food Science and Human Wellness 2024年第2期13卷 823-829页

作者： Sai Wang Rui ma Chengqiang li ling Zhang Haiyang Zhang Xuehan li Xiangzhao mao Qingdao Key Laboratory of Food Biotechnology College of Food Science and EngineeringOcean University of ChinaQingdao 266404China Key Laboratory of Biological Processing of Aquatic Products China National Light IndustryQingdao 266404China Laboratory for marine Drugs and Bioproducts of Qingdao National Laboratory for marine Science and Technology Qingdao 266237China

Sensitive monitoring of the target products during the biosynthesis process is crucial,and facile analytical approaches are urgently ***,phosphatidylserine(PS)was chosen as the model target,a colorimetric aptasensor was developed for the rapid quantitation in biosynthesis samples.A chimeric aptamer was constructed with two homogeneous original PS *** recognition between the chimeric aptamer and PS results in the desorption of aptamer from the surface of the AuNPs nanozyme,and the peroxidase-like enzymatic activity of the AuNPs nanozyme was weakened in a relationship with the different *** developed aptasensor performed well when applied for analyzing PS in biosynthesis *** aptasensor offers good sensitivity and selectivity,under optimal conditions,achieving monitoring and quantitation of PS in the range of 2.5-80.0μmol/L,with a limit of detection at 536.2 nmol/***,the aptasensor provides good accuracy,with comparison rates of 98.17%-106.40%,when compared with the *** study provides a good reference for monitoring other biosynthesized products and promoting the development of aptamers and aptasensors in real-world applications.

关键词： Phosphatidylserine Chimeric aptamer AuNPs nanozyme Colorimetric aptasensor

Serrated flow behavior of GH536 superalloy under different loading rates at room temperature

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Rare Metals 2024年第5期43卷 2317-2323页

作者： Wen-Xiang Gao Dong ma li-li Zhao Fan Ye ling Shao Su-Jun Wu School of materials Science and Technology Beihang UniversityBeijing100091China

Serrated flow phenomenon has been widely observed among different metals due to the potential influence on their *** tensile tests of nickel-based superalloy GH536 were carried out at loading rates of 0.06,0.60,3.60,and 36.00 mm·min^(-1)at room temperature,*** tensile stress-strain curves demonstrate repetitive and discontinuous yielding behavior,namely serrated *** is observed that the stress-strain curves were dominated by type B serration,and original annealing twin boundaries(TBs)were distorted to various degrees under comparatively different lower tensile *** contrast,the TBs almost disappear,and the type B serrations become smoother and regular under the higher loading *** phenomenon can be attributed to the interactions between TBs and dislocations during tensile *** effects of the mobile and immobile dislocations illustrate the unsteady amplitude of serrations observed in stress-strain *** electron microscope images of tested pieces reveal the interaction of dislocation and TB,with dislocation tangling around the TBs.

关键词： Nickel-based superalloy Serrations Twin boundaries Deformation mechanism

Experimental investigation of dynamic characteristics of leaching tubing for solution mining of salt cavern carbon and energy storage

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Petroleum Science 2024年第4期21卷 2703-2722页

作者： Yin-Ping li Xin-Bo Ge Xi-lin Shi Hong-ling ma State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences University of Chinese Academy of Sciences College of Energy and Mining Engineering Shandong University of Science and Technology State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology

Salt caverns are extensively utilized for storing various substances such as fossil energy, hydrogen,compressed air, nuclear waste, and industrial solid waste. In China, when the salt cavern is leached through single-well water solution mining with oil as a cushion, engineering challenges arise with the leaching tubing, leading to issues like damage and instability. These problems significantly hinder the progress of cavern construction and the control of cavern shape. The primary cause of this is the flowinduced vibration instability of leaching tubing within a confined space, which results in severe bending or damage to the tubing. This study presents a model experimental investigation on the dynamic characteristics of leaching tubing using a self-developed liquid-solid coupling physical model experiment apparatus. The experiment utilizes a silicone-rubber pipe(SRP) and a polycarbonate pipe(PCP) to examine the effects of various factors on the dynamic stability of cantilevered pipes conveying fluid. These factors include external space constraint, flexural rigidity, medium outside the pipe, overhanging length, and end conditions. The experiments reveal four dynamic response phenomena: water hammer, static buckling, chaotic motion, and flutter instability. The study further demonstrates that the length of the external space constraint has a direct impact on the flutter critical flow velocity of the cantilevered pipe conveying fluid. Additionally, the flutter critical flow velocity is influenced by the end conditions and different external media.

关键词： Salt cavern storage Solution mining Leaching tubing Experimental investigation Flutter instability

Effect of Sonic hedgehog gene-modified bone marrow mesenchymal stem cells on graft-induced retinal gliosis and retinal ganglion cells survival in diabetic mice

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 34-41页

作者： Tong Wang Hai-Chun li Jin ma Xi-ling Yu State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangdong Provincial Key Laboratory of Ophthalmology and Visual ScienceGuangzhou 510060Guangdong ProvinceChina

AIM:To investigate the effects of Sonic hedgehog(Shh)gene-modified bone marrow mesenchymal stem cells(MSCs)on graft-induced retinal gliosis and retinal ganglion cells(RGCs)survival in diabetic ***:Bone marrow-derived MSCs were genetically modified with the Shh gene to generate a stably transfected cell line of Shh-modified MSCs(MSC-Shh).Intravitreal injections of MSC-Shh and green fluorescent protein-modified MSCs(MSC-Gfp;control)were administered in diabetic *** 4wk,the effects of MSC-Shh on retinal gliosis were evaluated using fundus photography,and markers of gliosis were examined by immunofluorescence and Western *** neurotrophic factors expression and RGCs survival in the host retina were evaluated using Western blotting and *** mechanisms underlying the effects of MSC-Shh was ***:A significant reduction of proliferative vitreoretinopathy(PVR)was observed after intravitreal injection of MSC-Shh compared to *** downregulation of glial fibrillary acidic protein(GFAP)was demonstrated in the host retina after MSC-Shh administration compared to *** extracellular signal-regulated kinase 1/2(ERK1/2),protein kinase B(AKT)and phosphatidylin-ositol-3-kinase(PI3K)pathways were significantly downregulated after MSC-Shh administration compared to ***-derived neurotrophic factor(BDNF)and ciliary neurotrophic factor(CNTF)levels were significantly increased in the host retina,and RGCs loss was significantly prevented after MSC-Shh ***:MSC-Shh administration reduces graft-induced reactive gliosis following intravitreal injection in diabetic *** ERK1/2,AKT and PI3K pathways are involved in this ***-Shh also increases the levels of neurotrophic factors in the host retina and promoted RGCs survival in diabetic mice.

关键词： mesenchymal stem cells Sonic hedgehog signaling reactive gliosis diabetic retinopathy retinal ganglion cells

Nitrogen–sulfur co-doped porous carbon derived from asphalt as efficient catalyst for oxygen reduction

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Rare Metals 2024年第1期43卷 380-388页

作者： Jing-Sheng ma Ming-Zai Wu ling Chen li-Xing Zhang Ying Xiong Key Laboratory of Structure and Functional Regulation of Hybrid materials Ministry of EducationInstitute of EnergyHefei Comprehensive National Science CenterAnhui UniversityHefei 230601China

As an environment-friendly and low-cost petrochemical by-product, asphalt has great potential in the preparation of metal-free oxygen reduction electrocatalysts with excellent performance and outstanding stability. In this paper, we converted asphalt into porous carbon nanosheets by a simple activation method, using potassium citrate as the swelling agent.

关键词： stability porous catalyst

SYNTHESIS OF DERIVATIVES OF 3-β-D-XYLOPYRANOSYL-1,2,4-OXADIAZOLES

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Chinese Chemical Letters 1992年第8期3卷 597-600页

作者： ling Jiao DONG li li ling Tai ma li He ZHANG School of Pharmaceutical Sciences,Beijing Medical University,Beijing 100083

The synthesis of derivatives of 3-β-D-xylopyranosyl-1,2,4-oxadiazoles is accomplished by condensing protected β-D-xylopyranosyl amidoxime with acid anhydrides or various substituted benzoyl chlorides in good *** structures of now derivatives were identified by spectra and elemental analysis. The stability of 1,2,4-oxadiazole ring and mechanism of cyclization were. investigated.

关键词： D-XYLOPYRANOSYL-1,2,4-OXADIAZOLES SYNTHESIS OF DERIVATIVES OF 3 台五

Overview of the immunological mechanisms in hepatitis B virus reactivation:Implications for disease progression and management strategies

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World Journal of Gastroenterology 2024年第10期30卷 1295-1312页

作者： Hui ma Qing-Zhu Yan Jing-Ru ma Dong-Fu li Jun-ling Yang Department of Clinical Laboratory The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Ultrasound Medicine The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Digestive Diseases Center Department of Hepatopancreatobiliary MedicineThe Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Respiratory and Critical Care Medicine The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina

Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease *** review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and *** delves into host immune responses and reactivation’s delicate balance,spanning innate and adaptive *** factors’disruption of this balance,as are interac-tions between viral antigens,immune cells,cytokine networks,and immune checkpoint pathways,are ***,the roles of T cells,natural killer cells,and antigen-presenting cells are discussed,highlighting their influence on disease *** reactivation’s impact on disease severity,hepatic flares,liver fibrosis progression,and hepatocellular carcinoma is *** strategies,including anti-viral and immunomodulatory approaches,are critically *** role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent *** conclusion,this compre-hensive review furnishes a holistic view of the immunological mechanisms that propel HBV *** a dedicated focus on understanding its implic-ations for disease progression and the prospects of efficient management stra-tegies,this article contributes significantly to the knowledge *** more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches,ultimately enhancing disease management and elevating patient *** dynamic landscape of management strategies is critically scrutinized,spanning anti-viral and immunomodulatory *** role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation.

关键词： Hepatitis B virus reactivation Immunological mechanisms Disease progression management strategies Immune response

Effect of low-degree astigmatism on the objective visual quality

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1086-1093页

作者： ling-Ying Ye Shu-Feng li Jing-Jing Zuo Jin li Hui-Xiang ma National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina

AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corrected-to-normal *** cylindrical lenses(0,0.5,0.75,1.0,and 1.25 D)were placed at the axial direction(180°,45°,90°,and 135°)in front of the eyes with the best correction to form 16 types of regular low-degree *** was used to detect the objective visual quality,recorded as the objective scattering index(OSI),OQAS values at contrasts of 100%,20%,and 9%predictive visual acuity(OV100%,OV20%,and OV9%),modulation transfer function cut-off(MTFcut-off)and Strehl ratio(SR).The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality ***:Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were *** increase of OSI per degree of astigmatism at 180°,45°,90°,and 135°axis were 0.38(95%CI:0.35,0.42),0.50(95%CI:0.46,0.53),0.49(95%CI:0.45,0.54)and 0.37(95%CI:0.34,0.41),*** decrease of MTFcut-off per degree of astigmatism at 180°,45°,90°,and 135°axis were-10.30(95%CI:-11.43,-9.16),-12.73(95%CI:-13.62,-11.86),-12.75(95%CI:-13.79,-11.70),and-9.97(95%CI:-10.92,-9.03),*** the same astigmatism degree,OSI at 45°and 90°axis were higher than that at 0°and 135°axis,while MTFcut-off were ***:Low astigmatism of only 0.50 D can significantly reduce the objective visual quality.

关键词： low-degree astigmatism objective visual quality Optical Quality Analysis System