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Synergistic effect of silicon availability and salinity on metal adsorption in a common estuarine diatom

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Journal of Environmental Sciences 2025年第2期148卷 364-374页

作者： Fengyuan chen jie Ma Ke Pan SZU-HKUST Joint PhD Program in Marine Environmental Science Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Marine Microbiome Engineering Institute for Advanced StudyShenzhen UniversityShenzhen 518060China Department of Ocean Science The Hong Kong University of Science and TechnologyHong Kong 999077China

Increasing nitrogen and phosphorus discharge and decreasing sediment input have made silicon(Si)a limiting element for diatoms in *** in nutrient structure and salinity fluctuation can greatly affect metal uptake by estuarine ***,the combined effects of Si and salinity on metal accumulation in these diatoms have not been *** this study,we aimed to investigate how salinity and Si availability combine to influence the adsorption of metals by a widely distributed diatom Phaeodactylum *** data indicate that replete Si and low salinity in seawater can enhance cadmium and copper adsorption onto the diatom *** the single-cell level,surface potential was a dominant factor determining metal adsorption,while surface roughness also contributed to the highermetal loading capacity at lower *** a combination of noninvasive micro-test technology,atomic force microscopy,X-ray photoelectron spectroscopy,and Fourier transform infrared spectroscopy,we demonstrate that the diversity and abundance of the functional groups embedded in diatom cell walls vary with salinity and Si *** results in a change in the cell surface potential and transient metal *** study provides novel mechanisms to explain the highly variable metal adsorption capacity of a model estuarine diatom.

关键词： Diatom Metal adsorption Silicon Salinity Functional group Surface potential

Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第1期68卷 241-248页

作者： Ziqiang Wang Yasu chen jie Li chen Zhu Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai 200240China

We report a novel cyano migration-mediated radical-polar crossover process,whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently *** transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic *** studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution,leading to the formation of the cyclopropane derivatives.

关键词： cyclopropanation cyano migration radical-polar crossover radical reactions

Interfacial behaviors between ZG13Cr9Mo1VNbN stainless steel and chromite sand

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Journal of Iron and Steel Research International 2025年第1期32卷 129-143页

作者： Shi-sen Li Xi-min Zang Ji-lin chen jie Yang Yu-an Jing Zhi-ying Wang Ling-zhong Kong School of Materials and Metallurgy University of Science and Technology LiaoningAnshan114051LiaoningChina School of Material Science and Engineering Shenyang University of TechnologyShenyang110870LiaoningChina Central Iron and Steel Research Institute Co. Ltd.Beijing100081China Xingtai Iron and Steel Co. Ltd.Xingtai054027HebeiChina

To elucidate the formation mechanisms of burn-on sand and metal penetration during sand casting,some laboratory experiments were carried out at different temperatures(1813,1833,1853,and 1873 K)and holding time(20,40,60,and 90 min)to simulate the interaction between ZG13Cr9Mo1VNbN stainless steel and chromite *** results demonstrate that the defects primarily consist of a mixture of the liquid phase,chromite,and *** main components of the liquid phase are SiO_(2),MnO,MgO,Cr_(2)O_(3),FeO,and Al_(2)O_(3),and the formation of Cr_(2)O_(3)through interfacial redox reactions has been *** presence of a liquid phase plays a pivotal role in influencing burn-on sand and metal *** reactions are prioritized,with burn-on sand maintaining a predominant *** the liquid phase quantity within the sand escalates,there is a corresponding incremental rise in the incidence of metal *** a minimal presence of the silicon element in steel can impact the liquid phase’s ***,the decomposition or dissolution of chromite sand is a significant factor in the development of burn-on sand and metal ***,a thorough investigation into the conditions and contributing factors of this phenomenon is essential for its effective management and mitigation.

关键词： Heat-resistant steel Chromite sand Interfacial reaction Burn-on sand Metal penetration Temperature Holding time

Dynamic behaviors of graphene platelets-reinforced metal foam piezoelectric beams with velocity feedback control

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 63-80页

作者： jie chen Xinyue ZHANG Mingyang FAN School of Mathematics Statistics and Mechanics Beijing University of Technology College of Mechanical & Energy Engineering Beijing University of Technology

Graphene platelets(GPLs)-reinforced metal foam structures enhance the mechanical properties while maintaining the lightweight characteristics of metal foams. Further bonding piezoelectric actuator and sensor layers on the surfaces of GPLs-reinforced metal foam beams enables active vibration control, greatly expanding their applications in the aerospace industry. For the first time, this paper investigates the vibration characteristics and active vibration control of GPLs-reinforced metal foam beams with surfacebonded piezoelectric layers. The constant velocity feedback scheme is used to design the closed-loop controller including piezoelectric actuators and sensors. The effects of the GPLs on the linear and nonlinear free vibrations of the beams are numerically *** Newmark-β method combined with Newton's iteration technique is used to calculate the nonlinear responses of the beams under different load forms including harmonic loads,impact loads, and moving loads. Additionally, special attention is given to the vibration reduction performance of the velocity feedback control on the responses of the beam.

关键词： active vibration control metal foam nonlinear free vibration O341 piezoelectric material velocity feedback control

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大挠度弯曲薄板的回弹有限元分析

塑性工程学报 2005年第6期12卷 59-62页

作者：陈英杰燕山大学秦皇岛066004

通过引入有限变形回弹反耦联系统和反耦联方程的概念,由回弹势能原理建立了板成形的大挠度回弹有限元法。并应用此方法对板的成形回弹进行模拟计算,将计算结果与实验结果进行了比较。

关键词：反耦联方程大挠度回弹势能原理回弹有限元法模拟计算实验结果

Interplay between creeping fat and gut microbiota: A brand-new perspective on fecal microbiota transplantation in Crohn's disease

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World Journal of Gastroenterology 2025年第2期31卷 138-143页

作者： ying Wang jie Liu Department of Life Sciences and Medicine South District of Endoscopic CenterThe First Affiliated Hospital of University of Science and Technology of ChinaUniversity of Science and Technology of ChinaHefei 230001Anhui ProvinceChina Department of Gastroenterology The First Affiliated Hospital of University of Science and Technology of ChinaHefei 230001Anhui ProvinceChina

Inflammatory bowel disease,particularly Crohn's disease(CD),has been linked to modifications in mesenteric adipose tissue(MAT)and the phenomenon known as"creeping fat"(CrF).The presence of CrF is believed to serve as a predictor for early clinical recurrence following surgical intervention in patients with ***,the incorporation of the mesentery during ileocolic resection for CD has been correlated with a decrease in surgical recurrence,indicating the significant role of MAT in the pathogenesis of *** numerous studies have indicated that dysbiosis of the gut microbiota is a critical factor in the development of CD,the functional implications of translocated microbiota within the MAT of CD patients remain *** manuscript commentary discusses a recent basic research conducted by Wu et *** their study,intestinal bacteria from individuals were transplanted into CD model mice,revealing that fecal microbiota trans-plantation(FMT)from healthy donors alleviated CD symptoms,whereas FMT from CD patients exacerbated these ***,FMT was found to affect intestinal permeability,barrier function,and the levels of proinflammatory factors and ***,these findings suggest that targeting MAT and CrF may hold therapeutic potential for patients with ***,the study did not evaluate the composition of the intestinal microbiota of the donors or the subsequent alterations in the gut ***,the gut microbiota plays a crucial role in the histopathology of CD,and thus,targeting MAT and CrF may represent a promising avenue for treatment in this patient population.

关键词： Crohn's disease Mesenteric adipose tissue Creeping fat Fecal microbiota transplantation Gut microbiota

Utilizing BP neural networks to accurately reconstruct the tritium depth profile in materials for BIXS

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Nuclear Science and Techniques 2025年第1期36卷 103-114页

作者： chen Zhao Wei Jin Yan Shi Chang-An chen Yi-ying Zhao Institute of Materials China Academy of Engineering PhysicsJiangyou 621908China

β-ray-induced X-ray spectroscopy(BIXS)is a promising method for tritium detection in solid materials because of its unique advantages,such as large detection depth,nondestructive testing capabilities,and low requirements for sample ***,high-accuracy reconstruction of the tritium depth profile remains a significant challenge for this *** this study,a novel reconstruction method based on a backpropagation(BP)neural network algorithm that demonstrates high accuracy,broad applicability,and robust noise resistance is *** average reconstruction error calculated using the BP network(8.0%)was much lower than that obtained using traditional numerical methods(26.5%).In addition,the BP method can accurately reconstruct BIX spectra of samples with an unknown range of tritium and exhibits wide applicability to spectra with various tritium ***,the BP network demonstrates superior accuracy and stability compared to numerical methods when reconstructing the spectra,with a relative uncertainty ranging from 0 to 10%.This study highlights the advantages of BP networks in accurately reconstructing the tritium depth profile from BIXS and promotes their further application in tritium detection.

关键词： β-ray-induced X-ray spectroscopy Tritium detection BP network Ridge regression Reconstruction problem

Risk factors for biometry prediction error by Barrett Universal II intraocular lens formula in Chinese patients

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 74-78页

作者： Xu-Hao chen ying Hong Xiang-Han Ke Si-Jia Song Yu-jie Cen Chun Zhang Beijing Key Laboratory of Restoration of Damaged Ocular Nerve Department of OphthalmologyPeking University Third HospitalBeijing 100191China 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 influence of postoperative intraocular lens(IOL)positions on the accuracy of cataract surgery and examine the predictive factors of postoperative biometry prediction errors using the Barrett Universal II(BUII)IOL formula for ***:The prospective study included patients who had undergone cataract surgery performed by a single surgeon from June 2020 to April *** collected data included the best-corrected visual acuity(BCVA),corneal curvature,preoperative and postoperative central anterior chamber depths(ACD),axial length(AXL),IOL power,and refractive *** formula was used to calculate the IOL *** mean absolute error(MAE)was calculated,and all the participants were divided into two groups *** t-tests were applied to compare the variables between *** regression analysis was used to analyze the influence of age,AXL,corneal curvature,and preoperative and postoperative ACD on ***:A total of 261 patients were *** 243(93.1%)and 18(6.9%)had postoperative MAE1 D,*** number of females was higher in patients with MAE>1 D(χ^(2)=3.833,P=0.039).The postoperative BCVA(logMAR)of patients with MAE>1 D was significantly worse(t=-2.448;P=0.025).After adjusting for gender in the logistic model,the risk of postoperative refractive errors was higher in patients with a shallow postoperative anterior chamber[odds ratio=0.346;95% confidence interval(CI):0.164,0.730,P=0.005].CONCLUSION:Risk factors for biometry prediction error after cataract surgery include the patient’s sex and postoperative *** with a shallow postoperative anterior chamber are prone to have refractive errors.

关键词： intraocular lens power calculation gender anterior chamber depth biometry prediction error

抛物线性限制势二能级系统量子点量子比特的温度效应

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物理学报 2008年第11期57卷 6758-6762页

作者：陈英杰肖景林曲阜师范大学物理工程学院曲阜273165 内蒙古民族大学物理与机电学院通辽028043

应用Pekar变分方法,在抛物量子点中电子与体纵光学声子强耦合条件下,得出了电子的基态和第一激发态的本征能量及基态和第一激发态的本征波函数.以量子点中这样的二能级体系作为一个量子比特.当电子处于基态和第一激发态的叠加态时,计算... 详细信息

应用Pekar变分方法,在抛物量子点中电子与体纵光学声子强耦合条件下,得出了电子的基态和第一激发态的本征能量及基态和第一激发态的本征波函数.以量子点中这样的二能级体系作为一个量子比特.当电子处于基态和第一激发态的叠加态时,计算出电子在时空中作周期性振荡的概率分布.并且得出了概率分布随温度及耦合强度的变化关系.

关键词：量子点量子比特温度效应