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Enhancement of catalytic activity for hydrogenation of nitroaromatic by anionic metal-organic framework

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Chinese Chemical Letters 2024年第3期35卷 144-148页

作者： Qi Wu Anyang Li Ruibo He Yaxi Wu lei hou Guoping Yang Wenyan Zhang Yao-Yu Wang Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710127China

Nitroaromatic hydrogenation catalysis without precious metals remains a longstanding *** rate of electron transfer is the crucial factor affecting hydrogenation ***,an ionic Cd-based metal-organic framework(I-Cd-MOF)exhibiting a unique structure with one-dimensional(1D)opening nanochannels and good electron transfer ability was synthesized for catalyzing hydrogenation of 4-nitrophenol(4-NP).The catalytic activity of the unique I-Cd-MOF without noble metals is detected,which is higher than most reported noble metal ***,the reaction rate of I-Cd-MOF(4.28 min^(-1))is about 47.6 times higher than that of the Cd-based neutral MOF(N-Cd-MOF)with the similar crystalline *** chromatograph mass spectrometer(LC-MS)and theoretical results demonstrate that 4-NP and five intermediates are stabilized in the channels of I-Cd-MOF,which increases the possibility of contact with H^*and H_(2)g enerated at the Cd *** I-Cd-MOF was extended to other nitroaromatic hydrogenation catalysis,which still displays excellent *** importantly,the I-MOF@Filter membrane was successfully constructed for continuous hydrogenation catalytic reactions,which maintains a high catalytic performance after 7 cycles of recycling without *** work fills in the application of the I-MOFs in hydrogenation catalytic reactions and provides an effective way for the rapid and green degradation of nitroaromatic compounds.

关键词： Anions Metal-organic frameworks Catalysis Electron transfer Hydrogen production

High-static-low-dynamic stiffness isolator based on an electromagnetic negative stiffness spring with long linear stroke

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Science China(Technological Sciences) 2024年第3期67卷 740-752页

作者： YUAN ShuJin WU YaJun SONG DaiPing PU HuaYan MOU LiSheng hou lei ZHAO Jinglei LI XuePing LUO Jun WU Jie HUANG XiaoXu State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China China Aerodynamics Research and Development Center Mianyang 621000China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

Negative stiffness mechanisms can improve low-frequency vibration isolation performance and have been widely used in the vibration isolation of precision equipment. However, the negative stiffness mechanism usually introduces a nonlinear stiffness,resulting in a nonlinear response and worsening the vibration isolation performance, especially under large amplitude *** this paper, an electromagnetic spring with linear negative stiffness(ESLNS) is proposed, in which the antagonistic ampere forces of the energized coils are used to generate negative stiffness within a long linear stroke. The magnetic field distribution is improved through the design of the magnetic circuit, thereby increasing the stiffness generation efficiency. The stiffness can be adjusted bidirectionally by current within the range of positive and negative stiffness. An electromagnetic stiffness model was established based on the equivalent magnetic circuit method. Experimental measurements verified the accuracy of the model and proved the linearity of the electromagnetic spring. A vibration isolator with high static and low dynamic stiffness(HSLDS) based on the ESLNS is designed and tested. The experimental results prove that the introduction of the ESLNS can effectively expand the isolation frequency band without changing the equilibrium position. Moreover, the vibration isolator with ESLNS does not produce nonlinear response. The proposed electromagnetic spring with linear negative stiffness extends the application range of HSLDS isolators to a large amplitude vibration environment.

关键词： linear negative stiffness mechanism low-frequency vibration isolation electromagnetic spring vibration control

Simulation of deuterium pellet ablation and deposition in the EAST tokamak with HPI2 code

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Chinese Physics B 2024年第4期33卷 561-569页

作者：李大正张洁侯吉磊李懋孙继忠 Key Laboratory of Materials Modification by Laser Ionand Electron BeamsSchool of PhysicsDalian University of TechnologyDalian 116024China Department of Plasma Physics and Fusion Engineering University of Science and Technology of ChinaHefei 230026China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China

Pellet injection is a primary method for fueling the plasma in magnetic confinement *** that goal the knowledges of pellet ablation and deposition profiles are *** the present study,the pellet fueling code HPI2 was used to predict the ablation and deposition profiles of deuterium pellets injected into a typical H-mode discharge on the EAST *** ablation and deposition profiles were evaluated for various pellet injection locations,with the aim at optimizing the pellet injection to obtain a deep fueling *** this study,we investigate the effect of the injection angle on the deposition depth of the pellet at different velocities and *** ablation and deposition of the injected pellet are mainly studied at each injection position for three different injection angles:0°,45°,and 60°.The pellet injection on the high field side(HFS)can achieve a more ideal deposition depth than on the low field side(LFS).Among these angles,horizontal injection on the middle plane is relatively better on either the HFS or the *** the injection location is 0.468 m below the middle plane on the HFS or 0.40 m above the middle plane of the LFS,it can achieve a similar deposition depth to the one of its corresponding *** the pre-cooling effect is taken into account,the deposition depth is predicted to increase only slightly when the pellet is launched from the *** findings of this study will serve as a reference for the update of pellet injection systems for the EAST tokamak.

关键词： pellet injection pellet ablation HPI2 pellet deposition

Exploration of pathogenic microorganism within the small intestine of necrotizing enterocolitis

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World Journal of Pediatrics 2024年第2期20卷 165-172页

作者： Yan Wang Kun Jiang Qiao Xia Xia Kang Shan Wang Ji-Hong Yu Wen-Feng Ni Xiao-Qin Qi Ying-Na Zhang Jin-Bao Han Gang Liu lei hou Zhi-Chun Feng Liu-Ming Huang Clinical Biobank Center Medical Innovation Research Division of ChinesePLA General HospitalBeijingChina Institute of Basic Medical Sciences Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Senior Department of Pediatrics The Seventh Medical Center of PLA General HospitalBeijing 100700China Department of Neurology The First Medical CenterChinese PLA General HospitalBeijing 100853China Department of Emergency Center National Center for Children's HealthBeijing Children's HospitalCapital Medical UniversityBeijing 100045China

Background Necrotizing enterocolitis(NEC)is the most common severe gastrointestinal emergency in *** designed this study to identify the pathogenic microorganisms of NEC in the microbiota of the small intestine of *** Using the 16S ribosomal DNA(rDNA)sequencing method,we compared and analyzed the structure and diversity of microbiotas in the intestinal feces of different groups of neonates:patients undergoing jejunostomy to treat NEC(NP group),neonates undergoing jejunostomy to treat other conditions(NN group),and neonates with NEC undergoing conservative treatment(NC group).We took intestinal feces and saliva samples from patients at different time *** The beta diversities of the NP,NN,and NC groups were all *** comparing the beta diversities between different time points in the NP group,we found similar beta diversities at time points El to E3 but significant differences between the E2-E3 and E4 time points:the abundances of Klebsiella and Enterococcus(Proteobacteria)were higher at the E1-E3 time points;the abundance of Escherichia-Shigella(Proteobacteria)increased at the E2 time point,and the abundance of Klebsiella decreased significantly,whereas that of Streptococcus increased significantly at the E4 time *** Our results suggest that the pathological changes of intestinal necrosis in the small intestine of infants with NEC are not directly caused by excessive proliferation of pathogenic bacteria in the small *** sources of microbiota in the small intestine of neonates,especially in premature infants,may be affected by multiple factors.

关键词： Microbiota Necrotizing enterocolitis-Small intestine 16S rDNA

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小口径人工血管的研究现状及展望

医用生物力学 2024年第2期39卷 355-360页

作者：吴鑫侯磊许锋广西医科大学再生医学与医用生物资源开发应用省部共建协同创新中心广西再生医学重点实验室南宁530021 上海交通大学医学院附属松江医院心内科上海201600 上海交通大学医学院附属第九人民医院学科规划处上海200011

近年来,由于心血管疾病发生率逐渐上升,临床上对再生血管的需求日益增加。目前,大口径人工血管(直径>6 mm)已成功应用于临床,小口径人工血管(直径<6 mm)由于血栓形成、内膜增生、炎症反应和顺应性差导致血流动力学改变等原因,使其移植... 详细信息

近年来,由于心血管疾病发生率逐渐上升,临床上对再生血管的需求日益增加。目前,大口径人工血管(直径>6 mm)已成功应用于临床,小口径人工血管(直径<6 mm)由于血栓形成、内膜增生、炎症反应和顺应性差导致血流动力学改变等原因,使其移植后远期通畅率低,距离临床应用尚有一段距离。其中,快速内皮化、抑制血栓形成及与自体血管相匹配的顺应性仍是解决问题的关键。本文简述制备小口径人工血管常用材料及技术的特点,重点讨论提高人工血管生物相容性和顺应性的策略,并对未来的研究工作进行展望。

关键词：小口径人工血管生物相容性内皮化顺应性

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襄阳市农业产业化水平评价及其影响因素分析

南方农业 2024年第5期18卷 128-131页

作者：侯雷湖北文理学院资源环境与旅游学院湖北襄阳441053

农业产业化是推进农业现代化发展和助力乡村振兴的重要途径。为探究襄阳市农业产业化水平,分别从基础条件、经济效益、农业结构和产业规模4个方面共选取11个指标构建评价指标体系,采用熵权TOPSIS模型对农业产业化水平进行评价,并分析农... 详细信息

农业产业化是推进农业现代化发展和助力乡村振兴的重要途径。为探究襄阳市农业产业化水平,分别从基础条件、经济效益、农业结构和产业规模4个方面共选取11个指标构建评价指标体系,采用熵权TOPSIS模型对农业产业化水平进行评价,并分析农业产业化发展的影响因素。结果表明:2011—2021年襄阳市农业产业化水平总体呈现上升趋势,从影响因素来看,农业产业化水平主要受到科技、交通及产业发展水平的影响。

关键词：农业产业化熵权TOPSIS模型评价指标体系影响因素湖北省襄阳市

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煤矿悬臂式掘进机智能监测系统设计与应用

江西煤炭科技 2024年第1期 181-183页

作者：侯磊山西西山煤电股份有限公司西铭矿山西太原030052

为有效降低煤矿悬臂式掘进机故障发生率,全面掌握掘进机运行状态,本文对EBZ-220悬臂式掘进机状态监测及故障诊断技术进行研究,设计了一套基于多传感器及MCU控制的掘进机智能监测系统。该系统可对运行中掘进机的核心部位运行参数进行实... 详细信息

为有效降低煤矿悬臂式掘进机故障发生率,全面掌握掘进机运行状态,本文对EBZ-220悬臂式掘进机状态监测及故障诊断技术进行研究,设计了一套基于多传感器及MCU控制的掘进机智能监测系统。该系统可对运行中掘进机的核心部位运行参数进行实时采集、监测及超限报警。

关键词：掘进机状态监测故障诊断多传感器

中频电刺激联合康复训练对偏瘫患者步态参数、功能的影响

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医学信息 2024年第8期37卷 133-136页

作者：侯蕾天津市北辰区中医医院康复科

目的探究中频电刺激联合康复训练对偏瘫患者步态参数及功能的影响。方法选取2022年3月-2023年3月天津市北辰区中医医院收治的30例偏瘫患者，经随机数字表法分为对照组与观察组，各15例。对照组采用康复训练，观察组则采用中频电刺激... 详细信息

目的探究中频电刺激联合康复训练对偏瘫患者步态参数及功能的影响。方法选取2022年3月-2023年3月天津市北辰区中医医院收治的30例偏瘫患者，经随机数字表法分为对照组与观察组，各15例。对照组采用康复训练，观察组则采用中频电刺激联合康复训练，比较两组步态参数（步速、步频、患肢跨步长）、患侧肌力（Lovett肌力评分）、运动功能[Fugl-Meyer运动功能评分（FMA）]、平衡能力[Berg平衡量表（BBS）]、日常生活能力[Barthel指数（BI）]。结果两组康复治疗后步速、步频、患肢跨步长均大于康复治疗前，且观察组步速、步频、患肢跨步长大于对照组（P<0.05）；两组康复治疗后患侧Lovett肌力评分（上肢、下肢）均高于康复治疗前，且观察组患侧Lovett肌力评分（上肢、下肢）高于对照组（P<0.05）；两组康复治疗后FMA评分（上肢、下肢）均高于康复治疗前，且观察组FMA评分（上肢、下肢）高于对照组（P<0.05）；两组康复治疗后BBS、BI评分高于康复治疗前，且观察组BBS、BI评分高于对照组（P<0.05）。结论中频电刺激联合康复训练可改善偏瘫患者的步态参数，有利于患侧肌力与运动功能的强化，对其平衡能力及生活能力均具有良好改善作用。

关键词：偏瘫康复训练中频电刺激步态参数肌力运动功能

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架空乘人装置智能监控系统研究与设计

江西煤炭科技 2024年第2期 142-144页

作者：侯磊山西西山煤电股份有限公司西铭矿山西太原030052

针对目前煤矿架空乘人装置智能化程度低、运行监测不全面等问题,提出了一种基于PLC控制器控制、分布式传感器检测的驾空乘人装置智能监控系统。该系统可通过上位机及PLC控制器配合控制,实现装置的自动启停、自适应调速等功能,同时可对... 详细信息

针对目前煤矿架空乘人装置智能化程度低、运行监测不全面等问题,提出了一种基于PLC控制器控制、分布式传感器检测的驾空乘人装置智能监控系统。该系统可通过上位机及PLC控制器配合控制,实现装置的自动启停、自适应调速等功能,同时可对装置运行状态进行远程实时监测,有效提高煤矿架空乘人装置运输智能化程度。

关键词：煤矿架空乘人装置智能监控 PLC控制器自动启停