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甲状腺激素水平与孕妇不同妊娠期的相关性分析

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系统医学 2024年第12期9卷 161-163页

作者：孙东明潍坊市妇幼保健院检验科山东潍坊261021

目的探讨不同妊娠期与甲状腺激素水平的相关性。方法目的选取2020年1月—2023年12月潍坊市妇幼保健院收治的260例正常妊娠孕妇作为研究对象,依据不同妊娠期,将孕妇划分为妊娠早期孕妇组(n=87)、妊娠中期孕妇组(n=87)以及妊娠晚期孕妇组(... 详细信息

目的探讨不同妊娠期与甲状腺激素水平的相关性。方法目的选取2020年1月—2023年12月潍坊市妇幼保健院收治的260例正常妊娠孕妇作为研究对象,依据不同妊娠期,将孕妇划分为妊娠早期孕妇组(n=87)、妊娠中期孕妇组(n=87)以及妊娠晚期孕妇组(n=86)。比较3组的甲状腺激素水平,采用Pearson相关性系数分析甲状腺激素水平与不同妊娠期的相关性。结果与妊娠早期组、妊娠中期组比较,妊娠晚期组的游离三碘甲状腺原氨酸(Free Triiodothyronine,FT3)、游离甲状腺素(Free Thyroxine,FT4)水平较低,促甲状腺激素(Thyroid Stimulating Tormone,TSH)水平较高,差异有统计学意义(P均<0.05);与妊娠早期组比较,妊娠中期组的FT3、FT4水平较低,TSH水平较高,差异有统计学意义(P均<0.05)。FT3、FT4水平与妊娠周期呈负相关(r=-0.562、-0.327,P均<0.05),TSH与妊娠周期呈正相关(r=0.669,P<0.05)。结论不同妊娠期孕妇的甲状腺激素水平存在差异,FT3、FT4水平与妊娠周期为负相关关系,TSH水平与妊娠周期为正相关关系。

关键词：孕妇健康育龄女性甲状腺激素水平检验结果

On the use of H-inf criterion in channel estimation and precoding in massive MIMO systems

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Science China(Information Sciences) 2017年第2期60卷 151-164页

作者： Peng XU dongming WAnG Feng QI School of Computer Science and Engineering Northeastern University national Mobile Communications Research Laboratory Southeast University Key Laboratory of Opto-Electronic Information Processing Institute of AutomationChinese Academy of Science

In this paper, a channel estimation(CE) and precoding scheme by using H-infinity(H-inf) criterion for mitigation of pilot contamination(PC) in massive multiple input multiple output(MIMO) orthogonal frequency division multiplexing(OFDM) systems is investigated. Firstly, different thresholds in H-inf CE and precoding are considered. Secondly, asymptotic analysis is presented to simplify the H-inf precoding, which shows that the complexity of an order of magnitude is reduced. Thirdly, approximate downlink achievable data rates per user are studied for different CE and precoding schemes, such as H-inf and minimum mean square error(MMSE) CE, MMSE, zero-forcing(ZF) and H-inf precoding. The analysis shows that the proposed scheme can provide dual mitigation to the PC. That is, the H-inf CE mitigates the PC by adjusting its thresholds, and the H-inf precoding is utilized to suppress the PC by considering inter-cell interference. The numerical results show that joint use of H-inf CE and H-inf precoding outperforms existing schemes in terms of mitigation to the PC.

关键词： massive MIMO pilot contamination precoding channel estimation H-inf

Improving Mechanical Properties and Energy Absorption of Additive Manufacturing Lattice Structure by Struts’node Strengthening

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Acta Mechanica Solida Sinica 2022年第6期35卷 1004-1020页

作者： dongming Li Ruixian Qin Jianxin Xu Junxian Zhou Bingzhi Chen School of Mechanical Engineering Dalian Jiaotong UniversityDalian116028China School of Locomotive and Rolling Stock Engineering Dalian Jiaotong UniversityDalian116028China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian116028China

The lattice structure has unique performance and superior deformation behavior,which effectively stimulates the design and application of new lattice *** development of additive manufacturing technology makes it easy and efficient to manufacture complex lattice ***,it has been found that excessively high stress concentration exists at the struts’nodes during the compression of lattice ***,three node strengthening strategies were proposed to reduce stress concentration,which were adding fillet at nodes,using circular arc transition and changing the angle of ***,lattice structures were manufactured by selective laser melting *** surface morphology of the lattice structures was observed by scanning electron ***,the stress distribution and deformation mechanism of different lattice structures were investigated by quasi-static compression experiments and numerical ***,the Gibson–Ashby model was adopted to predict lattice structures’modulus and *** the energy absorptions of different structures were *** results revealed that the deformation mode of the optimized structures changed from shear failure to layer-by-layer *** with the hourglass lattice structure and gradient lattice structure,the mechanical properties of curve lattice structure were improved the most.

关键词： node strengthening Stress concentration Lattice structure Selective laser melting Deformation mode

Behavior and mechanism of graphene oxide-tris(4-aminophenyl)amine composites in adsorption of rare earth elements

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Journal of Rare Earths 2021年第1期39卷 90-97,I0004页

作者： Xiaoru Zhao Xinyu Jiang dongming Peng Jie Teng Jingang yu College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China School of Pharmacy Hunan University of Chinese MedicineChangsha 410208China College of Materials Science and Engineering Hunan UniversityChangsha 410082China

Three-dimensional(3D)graphene oxide-tris(4-aminophenyl)amine(GO-TAPAx:y)composites with different GO-to-TAPA mass ratios(x:y)were prepared by a facile one-step ultrasonic ***:y composites were characterized by scanning electron microscopy(SEM),nitrogen(n2)adsorption-desorption isotherms,Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and thermogravimetric analysis(TGA).Behavior and mechanism of GO-TAPAx:yco mposites for the adsorption of rare earth elements(REEs)were *** adso rption capacities of GO-TAPA1;2 composite for yb^3+,Er^3+,nd^3+,La^3+and y^3+are 30.88,26.52,20.60,11.24 and 10.52 mg/g,*** of some important parameters including GO-to-TAPA mass ratios,contact time,reaction temperature and initial yb^3+concentration on the adsorption were evaluated in *** spectral and XPS analyses show that the metal complexations and ion exchanges between nitrogen/oxygen-containing species of the adsorbents and REEs are involved in the adsorption procedure besides the conventional adsorption based on specific surface area,indicating the introduction of specific molecules onto GO is beneficial to its adsorption *** convenient reusability and applicability of GO-TAPAx:y composites toward real samples also demonstrate their feasibility in the enrichment of REE ions.

关键词： Graphene oxide Tris(4-aminophenyl)amine Enrichment Adsorption mechanism Rare earth elements

基于Pt-C_(3)n传感器的变压器油中溶解气体的吸附性能研究

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智慧电力 2024年第4期52卷 40-46,61页

作者：贾东明韩晓昆董翔衣书伟郭祥阳国网北京检修公司北京100073 三峡大学电气与新能源学院湖北宜昌443000

变压器的在线监测技术是全球能源互联网建设的重要保障,而变压器油中溶解气体的诊断被视为变压器故障的有效判据。采用密度泛函理论方法模拟了6种油中溶解气体在铂修饰的C3n纳米薄片的吸附过程,通过能带结构、态密度、差分电荷密度的计... 详细信息

变压器的在线监测技术是全球能源互联网建设的重要保障,而变压器油中溶解气体的诊断被视为变压器故障的有效判据。采用密度泛函理论方法模拟了6种油中溶解气体在铂修饰的C3n纳米薄片的吸附过程,通过能带结构、态密度、差分电荷密度的计算揭示相关的吸附和传感机理。结果表明铂修饰可以显著增强C3n纳米薄片的气敏响应能力,尤其是对CO和C_(2)H_(2)的捕捉能力,这主要归因于掺杂金属颗粒的d轨道电子层贡献。铂修饰C3n纳米薄片对变压器油中溶解气体的吸附能力排序为CO>C_(2)H_(2)>C_(2)H_(4)>H_(2)>CO_(2)>CH_(4)。吸附底物的电子特性发生较大变化。该研究为开发用于检测变压器油中溶解气体的高性能气敏传感器提供了理论基础。

关键词：油中溶解气体 C_(3)n纳米薄片表面改性气体吸附密度泛函理论

A DnA length reducing computing model for maximum independent set problem

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Chinese Science Bulletin 2010年第9期55卷 892-898页

作者： Zhang Cheng y.ng Jing Xu Jin Zhao dongming Peking Univ Key Lab High Confidence Software Technol Sch Elect Engn & Comp Sci Inst SoftwareMinist Educ Beijing 100871 Peoples R China

In this paper, a new molecular computing model is developed to solve the maximum independent set problem, based on the method of DnA length reducing. To solve the maximum independent set problem with n-vertices and m-edges, the time complexity is O(n+m). With the enlargement of the problem scale, the numbers of the required tubes will increase linearly. Two important methods in this experiment are single strand DnA (ssDnA) circularization and DnA length reducing. In addition, using reverse polymerase chain reaction (PCR) and circligase, the structure of DnA molecules is changed in each computing step, transforming from linear double strand DnA (dsDnA) to linear ssDnA and circular ssDnA. Using the circular DnA structure, the recombina-tion among DnA molecules is avoided. To verify this computing model, a small maximum independent set problem was solved.

关键词： nP-complete problem reverse PCR linear ssDnA circularization DnA length reducing

急性呼吸衰竭患者血清超敏C反应蛋白/白蛋白比值、诱骗受体3与撤机结局的关系

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包头医学院学报 2024年第2期40卷 58-61,86页

作者：任蔚时月生杨东明南阳医学高等专科学校第一附属医院呼吸与危重症医学科一病区河南南阳473000

目的:分析外周血超敏C反应蛋白/白蛋白比值(HCAR)、诱骗受体3(DcR3)与急性呼吸衰竭患者机械通气撤机结局的关系。方法:选取2020年11月至2021年11月接受机械通气治疗的102例急性呼吸衰竭患者为研究对象,根据撤机结局分为撤机失败组(n=21... 详细信息

目的:分析外周血超敏C反应蛋白/白蛋白比值(HCAR)、诱骗受体3(DcR3)与急性呼吸衰竭患者机械通气撤机结局的关系。方法:选取2020年11月至2021年11月接受机械通气治疗的102例急性呼吸衰竭患者为研究对象,根据撤机结局分为撤机失败组(n=21)、撤机成功组(n=81)。比较两组自主呼吸测试(SBT)前、撤机后外周血HCAR、DcR3水平,分析HCAR、DcR3水平与急性呼吸衰竭患者撤机失败的关系,外周血HCAR、DcR3水平联合对急性呼吸衰竭患者撤机失败的预测价值,分析不同水平HCAR、DcR3发生撤机失败危险度。结果:撤机失败组SBT前、撤机后外周血HCAR、DcR3水平高于撤机成功组(P<0.05);Logistic分析发现,外周血HCAR、DcR3水平与急性呼吸衰竭患者撤机失败显著相关(P<0.05);SBT前、撤机后外周血HCAR、DcR3水平联合预测优于单独预测;SBT前、撤机后外周血HCAR、DcR3水平高水平发生撤机失败的危险度是低水平的1.125、1.633、1.893、2.236倍(P<0.05)。结论:急性呼吸衰竭患者外周血HCAR、DcR3水平增加,各指标联合可以为预测急性呼吸衰竭患者机械通气撤机结局提供参考。

关键词：急性呼吸衰竭 HCAR DcR3 机械通气撤机结局

高效液相色谱荧光检测器法快速测定水果中乙氧基喹啉残留量研究

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食品安全导刊 2024年第3期 104-107,111页

作者：周志杰程雪韩东明济南市食品药品检验检测中心山东济南250000

建立了高效液相色谱仪串联荧光检测器测定苹果、梨样品中乙氧基喹啉残留量的方法。水果样品加入抗坏血酸后进行混合匀浆制样,向样品中加入0.1 mol·L^(-1)氢氧化钠溶液,在碱性条件下经正己烷进行3次提取,合并提取液氮吹至干,用含有抗坏... 详细信息

建立了高效液相色谱仪串联荧光检测器测定苹果、梨样品中乙氧基喹啉残留量的方法。水果样品加入抗坏血酸后进行混合匀浆制样,向样品中加入0.1 mol·L^(-1)氢氧化钠溶液,在碱性条件下经正己烷进行3次提取,合并提取液氮吹至干,用含有抗坏血酸的乙腈复溶,采用液相色谱荧光检测器法上机测定,外标法定量。荧光检测器激发波长365 nm,发射波长435 nm,流动相采用乙腈∶水=65∶35。结果表明,本方法在2.00~200.00 ng·mL^(-1)浓度范围内呈现良好线性关系,线性方程为y=1.06×10~4X-1.74×10~3,相关系数(r)为0.999 97。在0.02 mg·kg^(-1)、0.20 mg·kg^(-1)、1.00 mg·kg^(-1) 3个浓度水平进行加标,并进行6次平行实验,回收率在81.09%~86.43%,相对标准偏差为1.18%~3.09%。本方法简单快速,提取效率高,仪器灵敏度高,准确度和重复性良好,可用于水果中乙氧基喹啉残留量的测定。

关键词：乙氧基喹啉荧光检测器水果

Reduced graphene oxide with a highly restored π-conjugated structure for inkjet printing and its use in all-carbon transistors

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nano Research 2013年第11期6卷 842-852页

作者： y.ng Su Jinhong Du dongming Sun Chang Liu Huiming Cheng Sheny.ng national Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72 Wenhua RoadShenyang 110016 China

An inkjet-printed graphene film is of great importance for next-generation flexible, low cost and high performance electronic devices. However, due to the limitation of the inkjet printing process, the electrical conductivity of inkjet-printed graphene films is limited to n10 S＇cm-1, and achieving a high conductivity of the printed graphene films remains a big challenge. Here, we develop a ＂weak oxidation- vigorous exfoliation＂ strategy to tailor graphene oxide （GO） for meeting all the requirements of highly conductive inkjet-printed graphene films, including a more intact carbon plane and suitable size. The -conjugated structure of the resulting graphene has been restored to a high degree, and its printed films show an ultrahigh conductivity of -420 S-cm-I, which is tens of times higher than previously reported results, suggesting that, aside from developing a highly efficient reduction method, tuning the GO structure could be an alternative way to produce high quality graphene sheets. Using inkjet-printed graphene patterns as source/drain/gate electrodes, and semiconducting single-walled carbon nanotubes （SWCnTs） as channels, we fabricated an all-carbon field effect transistor which shows excellent performance （an on/off ratio of -104 and a mobility of -8 cm2＂V-l＇s-1） compared to previously reported CnT-based transistors, promising the use of nanocarbon materials, graphene and SWCnTs in printed electronics, especially where high performance and flexibility are needed.

关键词： inkjet printing graphene oxide high conductivity field effect transistor