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Perfect matchings on a type of lattices with toroidal boundary

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Applied Mathematics(A Journal of Chinese Universities) 2019年第1期34卷 33-44页

作者： FENG Xing zhang Lian-zhu zhang Ming-zu Faculty of Science Jiangxi University of Science and Technology School of Mathematical Science Xiamen University College of Mathematics and System Sciences Xinjiang University

Enumeration of perfect matchings on graphs has a longstanding interest in combinatorial mathematics. In this paper, we obtain some explicit expressions of the number of perfect matchings for a type of Archimedean lattices with toroidal boundary by applying Tesler's crossing orientations to obtain some Pfaffan orientations and enumerating their Pfaffans.

关键词： perfect matching Pfaffian orientation Archimedean lattice toroidal boundary

基于4-巯基苯甲酸和聚乙烯亚胺功能化纳米银的Cr^(3+)检测研究

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无机盐工业 2024年第4期56卷 78-84页

作者：祖明华曹亚鹏李衡刘玉敏张志昆河北科技大学化学与制药工程学院河北石家庄050018

水体中重金属离子含量过高会导致生态环境及人体健康的严重损害,检测水体中重金属离子含量十分重要。针对目前重金属离子检测灵敏度的问题,合成了4-巯基苯甲酸和聚乙烯亚胺修饰的纳米银材料,并构建了水溶液中铬离子检测体系。考察了不... 详细信息

水体中重金属离子含量过高会导致生态环境及人体健康的严重损害,检测水体中重金属离子含量十分重要。针对目前重金属离子检测灵敏度的问题,合成了4-巯基苯甲酸和聚乙烯亚胺修饰的纳米银材料,并构建了水溶液中铬离子检测体系。考察了不同修饰剂的浓度、体系pH对检测体系的影响。研究结果表明,当4-巯基苯甲酸浓度为1.1.^(-6)mol/L、聚乙烯亚胺质量浓度为2×1.^(-8)g/mL、pH=9.73时,该检测体系对Cr^(3+)具有良好的检测效果,在最优条件下检测限可达8×1.^(-7)mol/L。另外,该检测体系能够有效抵抗Al^(3+)、Ni^(2+)、K^(+)、Sr^(2+)、Co^(2+)、Cu^(2+)、Fe^(3+)、Zn^(2+)的干扰。在Cr^(3+)浓度为8×1.^(-7)~1.1.^(-5)mol/L时,符合曲线方程y=0.05906+0.50402/[1.1.^(2.59349×1.^(-6)-x)×569909.68](R^(2)=0.997)。该研究在检测污水中Cr^(3+)浓度方面具有较大的应用价值。

关键词：纳米银铬离子聚乙烯亚胺

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基于转录组的赤斑白条天牛嗅觉相关基因分析

南方农业学报 2024年第3期55卷 699-709页

作者：杨华芳张祖兵朱家颖柏天琦张宏瑞云南省热带作物科学研究所云南景洪666100 云南农业大学植物保护学院/云南生物资源保护与利用国家重点实验室云南昆明650201 西南林业大学/云南省森林灾害预警与控制重点实验室云南昆明650224 云南省农业科学院热带亚热带经济作物研究所云南保山678099

【目的】鉴定赤斑白条天牛(Batocera rufomaculata)嗅觉相关基因,筛选其中的差异表达基因(DEGs),为探明赤斑白条天牛嗅觉机制和基于嗅觉识别的天牛生物防治新途径研究提供理论支撑。【方法】采用Illumina NovaSeq6000测序平台对赤斑白... 详细信息

【目的】鉴定赤斑白条天牛(Batocera rufomaculata)嗅觉相关基因,筛选其中的差异表达基因(DEGs),为探明赤斑白条天牛嗅觉机制和基于嗅觉识别的天牛生物防治新途径研究提供理论支撑。【方法】采用Illumina NovaSeq6000测序平台对赤斑白条天牛触角、跗节和残体进行转录组测序,利用测序数据组装、注释、数据库序列检索、序列比对及差异基因分析等生物信息学分析方法挖掘嗅觉相关基因。【结果】转录组测序共获得1.7405条Unigenes,平均长度774 bp,N50为1.62 bp,GC含量42.93%。通过同源比对共鉴定出289个嗅觉基因,包括45个OBPs、22个CSPs、50个ORs、20个IRs、26个GRs、7个SNMPs、8个CXEs、82个CYPs、1.个AOXs和1.个GSTs基因。通过比较所有样本的转录组,共筛选到8861.DEGs,其中271.个上调表达、61.8个下调表达。基因功能注释和信号通路富集分析结果表明,有361.个DEGs注释到GO功能的生物学过程、细胞组分和分子功能,其中以生物学过程的占比最高,为34.87%;有4002个DEGs注释到KEGG数据库,参与96条通路。进一步对嗅觉基因进行分析发现,有1.4个嗅觉基因表达差异显著,其中79个上调表达、35个下调表达;OBP22、OBP29、CSP1.、CSP1.、SNMP1.OR41.CXE2和CYP1.基因在触角中的表达量均高于其他组织,CSP1.和CSP1.基因在雌虫中偏好表达,CYP34基因在雄性中偏好表达,且在跗节中高表达。【结论】筛选到赤斑白条天牛OBPs、CSPs、ORs、IRs、GRs、SNMPs、CXEs、CYPs、AOXs和GSTs等嗅觉相关基因。推测触角中高表达的OBPs和CSPs基因对赤斑白条天牛雌雄虫识别同类异性释放的信息素或寄主植物释放的挥发物起关键作用,在雌虫中偏好表达的CSPs基因可能在雌虫寻找产卵场所过程中发挥重要作用。

关键词：赤斑白条天牛转录组高通量测序嗅觉相关基因差异基因

弯刀综合征合并原始肝静脉丛1.报道并文献复习

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中华解剖与临床杂志 2024年第6期29卷 412-415页

作者：神斌肖晋昌徐浩祖茂衡张庆桥徐州医科大学附属医院介入放射科徐州221006

目的探讨弯刀综合征合并原始肝静脉丛的临床特征、诊断、治疗及预后,提高临床医生对该罕见病的认识。方法病例系列报告。回顾性分析2023年6月徐州医科大学附属医院收治的1.弯刀综合征合并原始肝静脉丛患者的临床资料。患者男,1.岁,体... 详细信息

目的探讨弯刀综合征合并原始肝静脉丛的临床特征、诊断、治疗及预后,提高临床医生对该罕见病的认识。方法病例系列报告。回顾性分析2023年6月徐州医科大学附属医院收治的1.弯刀综合征合并原始肝静脉丛患者的临床资料。患者男,1.岁,体检时腹部超声检查发现肝血管结构异常,血管造影表现为下腔静脉入房处闭塞,右中下肺静脉回流至下腔静脉闭塞远端,经原始肝静脉丛回流至右心房,三支肝静脉血流通畅,临床诊断弯刀综合征合并原始肝静脉丛。患者无明显临床症状和体征,未予治疗。在中国知网、万方数据库及PubMed数据库中以“弯刀综合征/scimitar syndrome”和“原始肝静脉丛/primitive hepatic venous plexus”为关键词,检索2023年6月之前有关弯刀综合征合并原始肝静脉丛的文献,共检出英文文献6篇(7例)。结合本文报道的1.,总结弯刀综合征合并原始肝静脉丛的临床特征、诊断、治疗及预后。结果本例患者结合文献报道的7例,共计8例患者,其中男2例、女6例,年龄2个月~1.岁。2例患者初诊年龄1.(婴儿型),表现为呼吸窘迫;6例患者初诊年龄>1.(儿童/成人型),其中1.表现为呼吸窘迫,其余5例无明显症状。8例患者中,合并右位心5例、右肺动脉或右肺发育不良5例、下腔静脉闭塞3例、下腔静脉狭窄3例、体-肺动脉侧支2例、房间隔缺损1.、房间隔缺损/动脉导管未闭1.。2例患者行手术治疗,其中1.行右肺静脉异位引流矫治术及下腔静脉修补术,另1.行右肺静脉异位引流矫治术及体-肺动脉栓塞术。3例患者有随访资料,随访期间生存良好。结论弯刀综合征合并原始肝静脉丛临床罕见,婴儿型临床表现较重、常合并心内畸形,儿童/成人型常无明显临床症状、肺动脉压力正常或轻度升高;弯刀综合征可以通过影像学检查尤其是血管造影诊断,根据患者情况可采用手术治疗或不予干预,患者预后良好。

关键词：遗传变异弯刀综合征原始肝静脉丛布加综合征临床特征

Using harmonic beam combining to generate pulse-burst in nonlinear optical laser

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Chinese Physics B 2024年第1期33卷 422-427页

作者：许元斋李珍玲张奥楠刘可张晶晶王小军彭钦军许祖彦 Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The ultrashort lasers working in pulse-burst mode reveal great machining performance in recent years. The number of pulses in bursts effects greatly on the removal rate and roughness. To generate a more equal amplitude of pulses in burst with linear polarization output and time gap adjustable, we propose a new method by the harmonic beam combining(HBC).The beam combining is commonly used in adding pulses into the output beam while maintaining the pulse waveform and beam quality. In the HBC, dichroic mirrors are used to combine laser pulses of fundamental wave(FW) into harmonic wave(HW), and nonlinear crystals are used to convert the FW into HW. Therefore, HBC can add arbitrarily more HW pulses to generate pulse-burst in linear polarization with simple structure. The amplitude of each pulse in bursts can be adjusted the same to increase the stability of the burst, the time gap of each pulse can be adjusted precisely by proper time delay. Because HBC adds pulses sequentially, the peak power density of the burst is the same as each pulse, pulses can be combined without concern of back-conversion which often occurs in high peak power density. In the demonstration, the extendibility of HBC was verified by combining two beams with a third beam. The combined efficiency rates were larger than 99%, and the beam quality of each beam was maintained at M^(2)≈1.4.

关键词： pulse-burst beam combining nonlinear optics

丙烯酸树脂添加剂对银纳米线透明导电膜的影响

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表面技术 2024年第18期53卷 192-198,209页

作者：欧孝宇张运生李旭陈琛黄鹏祖成奎中国建筑材料科学研究总院有限公司北京100024

目的通过丙烯酸树脂共混改性银纳米线溶液,弥补了银纳米线附着力差的缺点。方法采用不同槽深的线棒在玻璃基底上多次涂覆,制备了含不同丙烯酸树脂添加量的银纳米线透明导电膜,利用扫描电子显微镜、原子力显微镜、透光率/雾度测定仪、非... 详细信息

目的通过丙烯酸树脂共混改性银纳米线溶液,弥补了银纳米线附着力差的缺点。方法采用不同槽深的线棒在玻璃基底上多次涂覆,制备了含不同丙烯酸树脂添加量的银纳米线透明导电膜,利用扫描电子显微镜、原子力显微镜、透光率/雾度测定仪、非接触式电阻测试仪和百格法分别对银纳米线透明导电膜的表面形貌、表面粗糙度、透光率、雾度、方阻和附着力进行表征和测试,并通过最小二乘法将数据拟合得到银纳米线透明导电膜的透光率和方阻的关系。结果随着丙烯酸树脂添加量的增加,银纳米线透明导电膜的附着力增强。在线棒槽深相同、丙烯酸树脂溶液添加量≤6%时,随着涂覆次数的增加,银纳米线透明导电膜的透光性下降、雾度上升,方阻逐渐降低;通过数据拟合发现,透光率与方阻的平方呈负相关,采用更大线棒槽深制备的银纳米线透明导电膜有更高的品质因数,在丙烯酸树脂添加量为4%(体积分数)、线棒槽深20μm、涂覆1.次时,制备了透光率为84.3%、雾度为2.81.、方阻为28Ω/的高品质因数银纳米线透明导电膜。结论丙烯酸树脂溶液可以有效提升银纳米线透明导电膜的附着力,而丙烯酸树脂具有绝缘性,过量添加会增大银纳米线的接触电阻,使银纳米线网络的导电性下降。

关键词：银纳米线丙烯酸树脂棒涂光电性能品质因数附着力

Effects of Friction Heat on the Tribological Properties of the Woven Self-lubricating Liner

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Chinese Journal of Mechanical Engineering 2009年第6期22卷 918-924页

作者： YANG Yulin zu Dalei {1. Ruijun QI Xiaowen Key Laboratory of Fundamental Science of Mechanical Structure and Material Science under Extreme Condition for National Defence Yanshan University Qinhuangdao 066004 China State Key Laboratory of Metastable Materials Science and Technology. Yanskan Universiry Qinhuangdao 066004 China

In the dry-sliding process of the woven self-lubricating liner which is used in the self-lubricating spherical plain bearing, the friction heat plays an important role in the tribological performances of the liner. It has important value to study on the relationship between tribological performances of the liner and the friction heat. Unforttmately, up to now, published work on this relationship is quite scarce. Therefore, the effect of friction heat on the tribological performances of the liner was investigated in the present work. The tribological behaviors of the liner were evaluated by using the high temperature end surface wear tester. Scanning electron microscopy （SEM） was utilized to examine the morphologies of worn surfaces of the liner and study the failure modes. Differential scanning calorimetry （DSC） measurement and X-ray diffraction （XRD） analysis were performed to study the behaviors of the wear debris. The temperature rise on the worn surface was calculated according to classical models. SEM observation shows that the dominating wear mechanism for the liner is mainly affected by friction shear force, contact pressure and friction heat. Higher fusion heat for the wear debris than that for the pure polytetrafluroethylene （PTFE） indicates that the PTFE is the main portion of the wear debris, and, the PTFE in the wear debris shows a higher crystallisation degree owing to the effects of friction shear force and the friction heat. Combining the calculated temperature rise results with the wear rate of the liner, it can be concluded that the effects of temperature rise o n the tribological performances of the liner become more obvious when the temperature rise exceeds the glass transition temperature （Tg） of the PTFE. The wear resistance of the liner deteriorates dramatically when the temperature rise approaches to the melting point （Ton） of the PTFE. The tribological performances of the liner can be improved when the temperature rise exceeds Tg but is far l

关键词： woven fabric self-lubricating liner friction and wear friction heat differential scanning calorimetry thermal analysis transfer film

Powder Mixing Simulation Using Random Walk Model in Eco-material Preparation

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Journal of Wuhan University of Technology(Materials Science) 2004年第4期19卷 9-12页

作者：张季如 Wuhan University

The eco-material composition is not well-distributed in preparation. The eco-material samples were taken for computer image analysis, and its particle numbers and appearance parameters were measured. Based on the mechanism of connective mixing and diffusion, the particles distribution was simulated by a computer using the random walk with Levy flight. The results show that the eco-material microstructure simulated by a computer has an idealized porous structure. The particles distribution has a cluster characteristic that changes with the different size and number of particles in Levy flight trajectory. Each cluster consists of a collection of clusters and shows a structure of self-similar cluster,hence presents a well-defined fractal property. The results obtained from SEM observation are in good agreement with the numerical simulations, and show that the convective mixing presents in the Levy flight walk.

关键词： eco-material powder mixing convective mixing diffusion random walk Levy flight

Effect of electromechanical the properties of epitaxial boundary conditions on ferroelectric thin films

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Chinese Physics B 2011年第10期20卷 407-412页

作者： Zhou Zhi-Dong zhang Chun-{1. Jiang Quan Department of Materials Science and Engineering College of Materials Xiamen University Xiamen 361005 China Department of Civil Engineering School of Architecture and Civil Engineering Xiamen University Xiamen 361005 China College of Civil Engineering Nantong University Nantong 226019 China

The effects of internal stresses and depolarization fields on the properties of epitaxial ferroelectric perovskite thin films are discussed by employing the dynamic Ginzbur~Landau equation （DCLE）. The numerical solution for BaTiO3 film shows that internal stress and the depolarization field have the most effects on ferroelectric properties such as polarization, Curie temperature and susceptibility. With the increase of the thickness of the film, the polarization of epitaxia] ferroelectric thin film is enhanced rapidly under high internal compressively stress. With the thickness exceeding the critical thickness for dislocation formation, the polarization increases slowly and even weakens due to relaxed internal stresses and a weak electrical boundary condition. This indicates that the effects of mechanical and electrical boundary conditions both diminish for ferroelectric thick films. Consequently, our thermodynamic method is a full scale model that can predict the properties of ferroelectric perovskite films in a wide range of film thickness.

关键词： ferroelectric film internal stresses thermodynamic equations polarizations