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Chinese Physics B 2024年第10期33卷 213-219页

作者： Tong chen Sanjiang Yang Wanping Zhou Xuesong Mei d Haoxue Qiao School of Physics and Technology Wuhan UniversityWuhan 430072China College of Physics and Electronic Science Hubei Normal UniversityHuangshi 435002China School of Physics and Telecommunications Huanggang Normal UniversityHuanggang 438000China Wuhan Maritime Communication Research Institute Wuhan 430072China

The geometric structure parameters and radial density distribution of 1s2s1S excited state of the two-electron atomic system near the critical nuclear charge Z_(c)were calculated in detail under tripled Hylleraas basis *** to the localized behavior observed in the ground and the doubly excited 2p^(23)Pe states,for this state our results identify that while the behavior of the inner electron increasingly resembles that of a hydrogen-like atomic system,the outer electron in the excited state exhibits diffused hydrogen-like character and becomes perpendicular to the inner electron as nuclear charge Z approaches Z_(c).This study provides insights into the electronic structure and stability of the two-electron system in the vicinity of the critical nuclear charge.

关键词： critical nuclear charge two-electron atomic system geometric structure density distribution

Synthesis of carbon dots with predictable photoluminescence by the aid of machine learning

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Nano Research 2024年第3期17卷 1984-1989页

作者： chenyu Xing Gaoyu chen Xia Zhu Jiakun An Jianchun Bao Xuan Wang Xiuqing Zhou Xiuli Du Xiangxing Xu Jiangsu Key Laboratory of Biofunctional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China School of Mathematical Sciences Nanjing Normal UniversityNanjing 210023China State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

Carbon dots(CDs)have wide application potentials in optoelectronic devices,biology,medicine,chemical sensors,and quantum techniques due to their excellent fluorescent ***,synthesis of CDs with controllable spectrum is challenging because of the diversity of the CD components and *** this report,machine learning(ML)algorithms were applied to help the synthesis of CDs with predictable photoluminescence(PL)under the excitation wavelengths of 365 and 532 *** combination of precursors was used as the *** PL peaks of the strongest intensity(λ_(s))and the longest wavelength(λ_(l))were used as target *** six investigated ML models,the random forest(RF)model showed outstanding)performance in the prediction of the PL peaks.

关键词： carbon dots(CDs) synthesis photoluminescence(PL) machine learning(ML) PL prediction

碳酸司维拉姆治疗维持性血液透析患者的临床研究

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中国临床药理学杂志 2024年第8期40卷 1140-1144页

作者：杨巍程丽陈芳赵化南亳州市中医院肾病科安徽亳州236800

目的探究碳酸司维拉姆对维持性血液透析(MHD)患者血磷、血管钙化及甲状旁腺功能的影响。方法入选MHD患者为研究对象,依据治疗方案按照队列法分为试验组和对照组。对照组患者给予碳酸钙咀嚼片嚼服1.25 g,bid;试验组患者给予碳酸司维拉... 详细信息

目的探究碳酸司维拉姆对维持性血液透析(MHD)患者血磷、血管钙化及甲状旁腺功能的影响。方法入选MHD患者为研究对象,依据治疗方案按照队列法分为试验组和对照组。对照组患者给予碳酸钙咀嚼片嚼服1.25 g,bid;试验组患者给予碳酸司维拉姆片口服0.8 g,tid;2组疗程均为6个月。比较2组患者的临床疗效,比较血磷、血钙、冠状动脉钙化积分、甲状旁腺功能[全段甲状旁腺激素(iPTH)、甲状旁腺体积]和炎症因子[C反应蛋白(CRP)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)]水平,记录药物不良反应的发生情况。结果试验组和对照组的临床总有效率分别为92.45%(49例/53例)和77.55%(38例/49例),在统计学上差异有统计学意义(P0.05)。结论碳酸司维拉姆可降低MHD患者血磷水平,对血钙浓度影响较小,且能改善患者甲状旁腺功能,延缓血管钙化,临床应用效果较好。

关键词：碳酸司维拉姆维持性血液透析血磷甲状旁腺功能

Organic heterojunction synaptic device with ultra high recognition rate for neuromorphic computing

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Nano Research 2024年第6期17卷 5614-5620页

作者： Xuemeng Hu Jialin Meng Tianyang Feng Tianyu Wang Hao Zhu Qingqing Sun David Wei Zhang Lin chen School of Microelectronics State Key Laboratory of Integrated Chips and SystemsFudan UniversityShanghai 200433China National Integrated Circuit Innovation Center Shanghai 201203China

Traditional computing structures are blocked by the von Neumann bottleneck,and neuromorphic computing devices inspired by the human brain which integrate storage and computation have received more and more ***,a flexible organic device with 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene(C8-BTBT)and 2,9-didecyldinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene(C10-DNTT)heterostructural channel having excellent synaptic behaviors was fabricated on muscovite(MICA)substrate,which has a memory window greater than 20 *** device shows better electrical characteristics than organic field effect transistors with single organic semiconductor ***,the device simulates organism synaptic behaviors successfully,such as paired-pulse facilitation(PPF),long-term potentiation/depression(LTP/LTD)process,and transition from short-term memory(STM)to long-term memory(LTM)by optical and electrical ***,the neuromorphic computing function was verified using the Modified National Institute of Standards and Technology(MNIST)pattern recognition,with a recognition rate nearly 100%without *** research proposes a flexible organic heterojunction with the ultra-high recognition rate in MNIST pattern recognition and provides the possibility for future flexible wearable neuromorphic computing devices.

关键词： organic heterojunction neuromorphic computing synapse behaviors optical modulation Modified National Institute of Standards and Technology(MNIST)pattern recognition

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某医药企业职工职业紧张现状调研

职业卫生与应急救援 2024年第1期42卷 31-35页

作者：阳华陈静中南大学湘雅公共卫生学院湖南长沙410003

目的了解医药企业职工职业紧张现状及相关影响因素,探索职业人群心理健康建设的有效途径。方法2022年3-4月,通过《职业紧张量表》修订版(occupational stress inventory revised edition,OSI-R),采用自愿匿名方式对某医药企业职工完成... 详细信息

目的了解医药企业职工职业紧张现状及相关影响因素,探索职业人群心理健康建设的有效途径。方法2022年3-4月,通过《职业紧张量表》修订版(occupational stress inventory revised edition,OSI-R),采用自愿匿名方式对某医药企业职工完成在线问卷调研。采用SPSS 26.0统计学软件对数据进行分析。结果收到问卷2 730份,其中有效问卷2 516份,问卷有效回收率为92.2%。本次调研的企业职工在职业紧张量表中的各维度得分如下:职业任务紧张维度得分为(137.26±23.29)分,紧张反应维度得分为(87.50±22.17)分,应变能力得分为(132.69±18.67)分。职工在职业任务和紧张反应维度上中、高程度紧张水平的发生率分别为16.6%与17.6%,应变能力不足发生率为15.3%。以职业紧张量表中紧张反应维度得分作为响应变量,多元线性回归分析结果显示:职业任务各因子中,除任务模糊外,其他因子对紧张反应得分均有正向影响(β=0.164~0.439,P <0.01),而应变能力维度各因子对紧张反应得分均有负向影响(β=-0.224~-0.114,P <0.01);相比管理人员,生产线岗位人员紧张反应得分最低(β=-3.097,P <0.01)。结论该医药企业职工的职业紧张反应在整体上处于较好水平。保持良好的企业和组织社会心理因素以及提高对职工的社会支持资源,能有效缓解职业紧张。

关键词：医药企业企业职工职业紧张心理健康

Evaluation on cutting performance of novel PDC cutter for pipe jacking machine

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Underground Space 2024年第1期14卷 34-52页

作者： Long-Chuan Deng Yi-Xiang Yuan Xiao-Zhao Li Qian-Wei Zhuang Chi Zhang Yi-Wei chen School of Earth Sciences and Engineering Nanjing UniversityNanjingJiangsu 210023China Shanghai Tunnel Engineering Co.Ltd. Shanghai 200232China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhouJiangsu 221116China School of Mechanics and Engineering Science Shanghai UniversityShanghai 200444China

It is inevitable to cut reinforced concrete(RC)appeared in cross passage of city metro by cutting tools when constructing in densely populated *** previous cutters employed to cut RC are insufficient and easily damaged,so a new polycrystalline diamond compact(PDC)cutter is used to solve this *** on the theoretical analysis of cutting mechanism,both circular and tapered PDC cutters with cutting edge angle of 90and negative front rack angle of 10are used to cut *** peeling and breaking patterns of cutting concrete are proposed,the nodular and grainy chips are the preferred modes in cutting steel *** LS-DYNA is employed to investigate the cutting performance in *** simulation results show that the average and peak cutting forces increase with the growth of penetration depth,cutting speed,and roundness,and subsequently the recommended penetration depth less than 1.2 mm is obtained to cut RC due to the existence of steel ***,the linear cutting platform is adopted to investigate the force ability and damage state of PDC *** is concluded that the cutting force increases abruptly and fluctuates heavily when cutting the coarse *** patterns occurred in both numerical and experimental results are generally ***,the steel bar is pulled out and the PDC cutter is damaged at the penetration depth of 0.8 mm,while a good cut occurs at the penetration depth of 0.3 *** tapered PDC cutter with a relatively low cutting force is prone to be broken compared with circular PDC *** is suggested that the circular PDC cutter at the penetration depth of 0.3 mm should be used to cut RC in practical engineering.

关键词： PDC cutter RC Pipe jacking machine Linear cutting tests Damage and wear LS-DYNA

Temperature and heat flux bounds of convection driven by non-uniform internal heating

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Acta Mechanica Sinica 2024年第8期40卷 85-95页

作者： Liangbing chen An-Kang Gao Zimo Liao Zhenhua Wan Nansheng Liu Department of Modern Mechanics University of Science and Technology of ChinaHefei230026China

Convection driven by a spatially non-uniform internal heat source between two horizontal isothermal walls is studied by theoretical analysis and numerical simulation,in order to explore the bounds of the temperature and the vertical heat ***,the rigorous lower bound of the weighted average temperatureis derived analytically,by decomposing the temperature field into a background profile and a fluctuation *** bound obtained for the first time to consider non-uniform heat sources is found to be compatible with the existing bound obtained in uniform internal heat *** physical importance,an analytical relationship is derived as an inequality connectingand the average vertical heat flux,by employing the average heat flux on the bottom wall(qb)as an intermediary *** clarifies the intrinsic relation between the lower bound ofand the upper bound of,namely,these two bounds are essentially equivalent providing an easy way to obtain one from ***,the analytical bounds are extensively demonstrated through a comprehensive series of direct numerical simulations.

关键词： Internally heated convection Nonuniform internal heat source Analytical bounds Background method

护理本科生实习期间开展科研的意愿、态度和困难的现状调查

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中国高等医学教育 2024年第1期 36-39页

作者：陈妍梅花上海健康医学院上海201318

目的:对护理本科生实习期间开展科研的意愿、态度和困难展开调查并对原因进行分析。方法:采取便利抽样法,于2020年11月至2021年3月抽取上海市二级以上医院的护理本科实习生作为研究对象。采取一般情况调查表和护理本科生实习期间开展科... 详细信息

目的:对护理本科生实习期间开展科研的意愿、态度和困难展开调查并对原因进行分析。方法:采取便利抽样法,于2020年11月至2021年3月抽取上海市二级以上医院的护理本科实习生作为研究对象。采取一般情况调查表和护理本科生实习期间开展科研意愿、态度及困难调查表进行研究。结果:在160名学生中有78.12%(125名)的护理本科生愿意在实习期间做科研,有21.87%(35名)的护理本科生在实习期间对做科研不感兴趣、没有意向在实习期间做科研,希望在本科阶段参与科研项目;护理本科生实习期间对于科研的态度得分最高的是“实习期间做科研是为了能毕业”,得分为(4.00±1.13)分;其次是“本科生有必要进行知识培训”,得分为(3.83±1.29)分以及“能不能成为一名好护士与科研无关”,得分为(3.73±0.97)分;在本科护生们在参与或开展科研的过程中,主观上的困难排在前3位的分别是:科研学习知识匮乏(85.62%)、论文撰写困难(76.25%)、课题设计困难(56.87%)。客观上的困难排在前3位的分别是:时间精力不够(80%)、缺乏指导与帮带(73.12%)、奖励机制不够(68.75%)。结论:实习期间,护理本科生对科研持有积极的态度,他们愿意在实习期间开展科研,但在开展或参与过程中遇到较多困难,管理机构可根据实习期间护理本科生的特点开展针对性的培训,并适当给予辅导,帮助他们克服困难,顺利完成科研工作,有助于提升护理本科生的科研素养,促进护理本科生的科研管理。

关键词：护生本科科研态度困难

Relationship between hemoglobin glycation index and risk of hypoglycemia in type 2 diabetes with time-in-range in target

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World Journal of Diabetes 2024年第10期15卷 2058-2069页

作者： Bei-Si Lin Zhi-Gu Liu Dan-Rui chen Yan-Ling Yang Dai-Zhi Yang Jin-hua Yan Long-Yi Zeng Xu-Bin Yang Wen Xu Department of Endocrinology and Metabolism The Third Affiliated Hospital of Sun Yat-sen UniversityGuangdong Provincial Key Laboratory of DiabetologyGuangzhou 510630Guangdong ProvinceChina Department of Endocrinology and Metabolism The Third Affiliated Hospital(Zhaoqing Hospital)Sun Yat-sen UniversityZhaoqing 526000Guangdong ProvinceChina

BACKGROUND In patients with type 2 diabetes mellitus(T2DM),the risk of hypoglycemia also occurs in at a time-in-range(TIR)of>70%.The hemoglobin glycation index(HGI)is considered the best single factor for predicting hypoglycemia,and offers new perspectives for the individualized treatment of patients with well-controlled blood glucose levels that are easily ignored in clinical *** participants underwent a 7-days continuous glucose monitoring(CGM)using a retrospective CGM *** obtained glycemic variability indices using the CGM *** defined HGI as laboratory hemoglobin A1c minus the glucose management *** were categorized into low HGI(HGI70%.Our findings indicate that HGI is a reliable predictor of hypoglycemia in this population.

关键词： Hemoglobin glycation index Hypoglycemia Type 2 diabetes mellitus Continuous glucose monitoring Time in range

Simulation of charge-exchange induced NBI losses on EAST

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Plasma Science and Technology 2024年第9期26卷 133-147页

作者： Zhanhong LIN Feng WANG Ming XU Chaofeng SANG chen ZHANG Zhengxiong WANG Key Laboratory of Materials Modification by Beams of the Ministry of Education School of PhysicsDalian University of TechnologyDalian 116024People’s Republic of China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China

The neutral beam injection is widely adopted in tokamaks as a key heating tool,playing a crucial role in generating burning ***,the loss of beam ions can damage the first wall and reduce the heating efficiency,resulting in failure to maintain steady-state *** this work,the effect of neutral particles in the edge on fast ions generated by NBI in the Experimental Advanced Superconducting Tokamak(EAST)device is studied using the particle tracer code(PTC).The poloidal distribution of neutral particles is calculated by edge plasma simulation code *** this simulation,four beam lines in EAST are considered:co-current tangential(co-tang),co-current perpendicular(co-perp),counter-current tangential(ctr-tang)and counter-current perpendicular(ctr-perp).It is shown that,in the absence of neutral particles,the loss fraction of ctr-injection is considerably higher than that of the *** considering the neutral particles,it is found that the ctr-perp injection demonstrates a significant variation in particles loss fraction(ranging from 18.56%to 25.42%)compared to the other three injection *** terms of the loss fraction induced by neutral particles,ctr-injection exceeds co-injection,and perpendicular configuration exceeds tangential ***,the difference of charge exchange ratios of three different energy(full energy,half energy,one third energy)of the four injections can be attributed to variations in the poloidal trajectories associated with each of these ***,approximately half of fast ions which undergo neutralization directly lose to the first wall while the rest re-enter the bulk plasma and *** for the ctr-tang injection,the reionization ions from the other three injections exhibit effective confinement.

关键词： NBI charge exchange fast ion loss