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Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期7卷 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi Wang Jun-Lei Yin Xing-Yu Gao Shu-Feng Yang Hai-Feng Song jin-shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

关键词： First-principles calculations Phase stability TCP phases Thermodynamic properties W–Re alloy

Multi-channel microelectrode arrays for detection of single-cell level neural information in the hippocampus CA1 under general anesthesia induced by low-dose isoflurane

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Fundamental Research 2025年第1期5卷 72-81页

作者： Ruilin Hu Penghui Fan Yiding Wang jin shan Luyi jing Wei Xu Fan Mo Mixia Wang Yan Luo Ying Wang Xinxia Cai jinping Luo State Key Laboratory of Transducer Technology Aerospace Information Research InstituteChinese Academy of ScienceBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of Anesthesiology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200020China

Timely monitoring of anesthesia status during surgery is important to prevent an overdose of isoflurane ***,in-depth studies of the neural mechanisms of anesthetics are *** CA1 plays an important role during ***,a high spatiotemporal resolution microdevice technology for the accurate detection of deep brain nuclei is *** this research,four-shank 32-channel implantable microelectrode arrays(MEAs)were developed for the real-time recording of single-cell level neural information in rat hippocampal *** nanoparticles were modified onto the microelectrodes to substantially enhance the electrical properties of the microelectrode *** modified MEAs exhibited low impedance(11.5±1 kΩ)and small phase delay(-18.5°±2.54°),which enabled the MEAs to record single-cell level neural information with a high signal-to-noise *** MEAs were implanted into the CA1 nuclei of the anesthetized rats,and the electrophysiological signals were recorded under different degrees of anesthesia mediated by low-dose concentrations of *** recorded signals were analyzed in *** caused an inhibition of spike firing rate in hippocampal CA1 neurons,while inducing low-frequency oscillations in CA1,thus enhancing the low-frequency power of local field *** this manner,the spike firing rate and the power of local field potentials in CA1 could characterize the degree of isoflurane *** present study provides a technical tool to study the neural mechanisms of isoflurane anesthesia and a research method for monitoring the depth of isoflurane anesthesia in clinical practice.

关键词： Micro electrode array Hippocampal CA1 Isoflurane anesthesia Spike Local field potentials

Predictive value of a constructed artificial neural network model for microvascular invasion in hepatocellular carcinoma:A retrospective study

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 88-100页

作者： Hai-Yang Nong Yong-Yi Cen shan-jin Lu Rui-Sui Huang Qiong Chen Li-Feng Huang Jian-Ning Huang Xue Wei Man-Rong Liu Lin Li Ke Ding Department of Radiology The Third Affiliated Hospital of Guangxi Medical UniversityNanning 530031Guangxi Zhuang Autonomous RegionChina Department of Radiology Affiliated Hospital of Youjiang Medical University for NationalitiesBaise 533000Guangxi Zhuang Autonomous RegionChina Guangxi Clinical Medical Research Center for Hepatobiliary Diseases Affiliated Hospital of Youiiang Medical University for NationalitiesBaise 533000Guangxi Zhuang Autonomous RegionChina Department of Ultrasound The Third Affiliated Hospital of Guangxi Medical UniversityNanning 530031Guangxi Zhuang Autonomous RegionChina Department of Hepatobiliary Surgery The Third Affiliated Hospital of Guangxi Medical UniversityNanning 530031Guangxi Zhuang Autonomous RegionChina

BACKGROUND Microvascular invasion(MVI)is a significant risk factor for recurrence and metastasis following hepatocellular carcinoma(HCC)***,there is a paucity of preoperative evaluation approaches for *** To investigate the predictive value of texture features and radiological signs based on multiparametric magnetic resonance imaging in the non-invasive preoperative prediction of MVI in *** Clinical data from 97 HCC patients were retrospectively collected from January 2019 to July 2022 at our *** were classified into two groups:MVI-positive(n=57)and MVI-negative(n=40),based on postoperative pathological *** correlation between relevant radiological signs and MVI status was ***4.6 software and the mutual information method were employed to identify the top 10 dominant texture features,which were combined with radiological signs to construct artificial neural network(ANN)models for MVI *** predictive performance of the ANN models was evaluated using area under the curve,sensitivity,and *** models with relatively high predictive performance were screened using the DeLong test,and the regression model of multilayer feedforward ANN with backpropagation and error backpropagation learning method was used to evaluate the models’*** The absence of a pseudocapsule,an incomplete pseudocapsule,and the presence of tumor blood vessels were identified as independent predictors of HCC *** ANN model constructed using the dominant features of the combined group(pseudocapsule status+tumor blood vessels+arterial phase+venous phase)demonstrated the best predictive performance for MVI status and was found to be automated,highly operable,and very *** The ANN model constructed using the dominant features of the combined group can be recommended as a noninvasive method for preoperative prediction of HCC MVI status.

关键词： Hepatocellular carcinoma Texture analysis Magnetic resonance imaging Microvascular invasion Pseudocapsule Tumor blood vessels

山西壶关县草本药用植物生态位特征及种间联结性

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生态学杂志 2025年第2期44卷 493-501页

作者：郝嘉鑫金山铁军山西师范大学生命科学学院太原030032 长治学院生命科学系山西长治046011 太行山生态与环境研究所山西长治046011

生态位特征和种间联结对了解植物群落的结构和分类以及判断群落稳定性和群落发展趋势具有重要意义。以山西长治市壶关县22个优势野生草本药用植物为研究对象,采用Levins(BL)和shannon(BS)生态位宽度指数以及Pianka生态位重叠指数(Oik),... 详细信息

生态位特征和种间联结对了解植物群落的结构和分类以及判断群落稳定性和群落发展趋势具有重要意义。以山西长治市壶关县22个优势野生草本药用植物为研究对象,采用Levins(BL)和shannon(BS)生态位宽度指数以及Pianka生态位重叠指数(Oik),对研究区内的野生草本药用植物生态位特征进行分析;基于2×2列联表,利用种间联结系数(AC)、Jaccard指数(JD)、Ochiai指数(OI)、χ^(2)检验以及Pearson相关系数检验等方法,对研究区内的野生草本药用植物种间联结性进行分析。结果表明:(1)在22种药用植物中,生态位宽度指数(BL)最大的为地榆(63.369),其次为白莲蒿(58.276),最小的为黄芪(2.489);生态位宽度指数(BS)最大的为地榆(4.290),其次为沙参(4.247),最小的为黄芪(1.097);生态位重叠指数(Oik)最大的为刺儿菜与甘菊(0.562),其次为白莲蒿与阴行草(0.534),最小的重叠值为0,有112个。这说明,山西壶关县草本药用植物的生态位重叠程度整体较低,种间竞争不激烈,草本药用植物物种分布极为分散。(2)种间联结系数AC显示,在231个物种对中,有77个正联结种对,其中强正联结种对有11个,有154个负联结种对,其中强负联结有116个;种间联结χ^(2)检验显示,有77个正联结种对,其中极显著正联结有24个,有154个负联结种对,其中极显著负联结有7个;在Pearson相关系数中,有56个正联结种对,其中极显著正联结有17个,有175个负联结种对,其中极显著负联结有8个。(3)综合AC系数、JD指数、OI指数、χ^(2)检验和Pearson相关系数来看,壶关县药用植物种对中,负联结种对多于正联结种对,不显著联结的种对数多于显著联结的种对数,这表明壶关县野生草本药用植物种对间相似度较低,物种表现出独立分布的特征,容易受到外界干扰。总体而言,壶关县野生草本药用植物资源丰富,物种出现较为随机,种间竞争较弱,物种独立性较强,受到外界干扰时群落结构存在不稳定。本研究结果将对了解当地药用植物分布规律以及可持续利用提供重要依据。

关键词：药用植物重要值生态位宽度生态位重叠种间联结

示范与引导:李大钊和呔商群体价值观嬗变与建构

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华北理工大学学报(社会科学版) 2025年第1期25卷 93-98页

作者：秦善进唐山学院马克思主义学院河北唐山063000

在从传统工商业者向现代工商业群体转变过程中,呔商群体价值观不断嬗变,从建立在朴素爱国立场上的传统价值观逐步向以理性爱国为基石的现代价值观嬗变。呔商群体价值观的嬗变是多重因素相互作用的结果,其中李大钊的爱国情操、奋斗经历... 详细信息

在从传统工商业者向现代工商业群体转变过程中,呔商群体价值观不断嬗变,从建立在朴素爱国立场上的传统价值观逐步向以理性爱国为基石的现代价值观嬗变。呔商群体价值观的嬗变是多重因素相互作用的结果,其中李大钊的爱国情操、奋斗经历、道德品质等就是关键的一环。通过李大钊的示范与引导,呔商群体,尤其是第二代呔商以反帝爱国为立足点来重塑义利伦理观,构建出以理性爱国、务实坚韧、重义守信、开放包容、求变创新为内容的现代价值观。

关键词：李大钊呔商群体价值观嬗变建构影响

枸杞茶感官审评方法的建立及其主要呈香物质的探索

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食品工业科技 2025年第4期46卷 30-41页

作者：李元朝黎勤吉郭玉琼郝志龙金珊福建农林大学园艺学院茶学福建省高校重点实验室福建福州350002 福建农林大学安溪茶学院(数字经济学院) 福建安溪362406

为了建立枸杞芽、叶茶感官审评方法,以盖碗和柱形杯两种冲泡方式,开展冲泡时间和投茶量为变量的感官审评实验。通过理化指标和气相色谱-质谱(Gas Chromatography Mass Spectrometry,GC-MS)联用技术测定,分析枸杞芽、叶茶主要滋味物质和... 详细信息

为了建立枸杞芽、叶茶感官审评方法,以盖碗和柱形杯两种冲泡方式,开展冲泡时间和投茶量为变量的感官审评实验。通过理化指标和气相色谱-质谱(Gas Chromatography Mass Spectrometry,GC-MS)联用技术测定,分析枸杞芽、叶茶主要滋味物质和香气成分的差异,并明确枸杞茶的主要呈香物质。结果表明,4 g、2 min的柱形杯冲泡方式更适用于枸杞茶的审评,咸香(熟菜香)和甜香是枸杞茶的主要香气特征;根据正交偏最小二乘判别分析(OPLS-DA)模型的变量重要性投影(Variable Importance in Projection,VIP)值,筛选得到苯甲醛、3,5-辛二烯-2-酮、2,4-二叔丁基酚、甲基庚烯酮、正己醛、顺-2-戊烯-1-醇、松香芹醇、2,4-二甲基苯甲醛和苯乙烯9种香气成分为枸杞茶的主要呈香物质,根据它们的香型特征,推断这9种呈香物质可能是咸香(熟菜香)的主要贡献物。本研究可为枸杞茶感官审评体系的建立和等级划分提供参考,并对枸杞茶的香气品质研究提供一定理论依据。

关键词：枸杞茶感官审评品质香气成分咸香

Optimization of thermal processing parameters of Ti555211 alloy using processing maps based on Murty criterion

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Rare Metals 2016年第2期35卷 154-161页

作者： Zhen An jin-shan Li Yong Feng State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Isothermal compression testing of Ti555211 titanium alloys was carried out at deformation temperatures from 750 to 950 °C in 50 °C intervals with a strain rate of0.001-1.000 s^（-1）. The high-temperature deformation behavior of the Ti555211 alloy was characterized by analysis of stress-strain behavior, kinetics and processing maps. A constitutive equation was formulated to describe the flow stress as a function of deformation temperature and strain rate, and the calculated apparent activation energies are found to be 454.50 and 207.52 k J mol^（-1）in the a b-phase and b-phase regions, respectively. A processing map based on the Murty instability criterion was developed at a strain of 0.7. The maps exhibit two domains of peak efficiency from 750 to 950 °C. A ＊60 % peak efficiency occurs at 800-850 °C/0.001-0.010 s^（-1）. The other peak efficiency of ＊60 % occurs at C950 °C/0.001-0.010 s^（-1）, which can be considered to be the optimum condition for high-temperature working of this ***, at strain rates of higher than 1.000 s^（-1）and deformation temperatures of 750 and 950 °C, clear process flow lines and bands of flow localization occur in the hightemperature deformation process, which should be avoided in Ti555211 alloy hot processing. The mechanism in stability domain and instability domain was also discussed.

关键词： Ti555211 titanium alloy High temperature Deformation behavior Processing maps

Microstructure evolution of a new near-β titanium alloy:Ti555211 during high-temperature deformation

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Rare Metals 2015年第11期34卷 757-763页

作者： Zhen An jin-shan Li Yong Feng State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The isothermal compression testing of Ti555211 titanium alloys was carried out at deformation temperatures from 750 to 950 ℃ in 50 ℃ intervals,with strain rate of 0.001-1.000 s-1and height reduction of 20%-60%.The effect of processing parameters（deformation temperature,strain rate and deformation degree） on the microstructure evolution and the microstructure variables was *** results show that the content of primary α phase decreases with the increase in deformation *** effect of strain rate on microstructure variables of isothermally compressed Ti555211 alloy is mainly dependent on the deformation *** fine second α phase partly transforms to β phase due to the deformation heat effect at the high strain rate,α phase becomes globular with temperature increasing and strain rate *** contrast,α phase is refined with temperature decreasing and strain rate *** deformation degree has a little influence on the grain size and the morphology of primary α phase,but the effect of deformation degree on the morphology of second α phase is *** larger deformation degree is in favor of the globularization of lamellar α structure.

关键词： Titanium alloy High-temperature deformation Micros

Heterogeneous coverage method with multiple unmanned aerial vehicle assisted sink nodes

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High Technology Letters 2019年第4期25卷 395-400页

作者： jin shan jin Zhigang Electrical Automation and Information Engineering CollegeTianjin UniversityTianjin 300072P.R.China Fire and Rescue Department Bureau of Emergency Management of TianjinTianjin 300090P.R.China

A heterogeneous coverage method with multiple unmanned aerial vehicle assisted sink nodes(MUAVSs)for multi-objective optimization problem(MOP)is proposed,which is based on quantum wolf pack evolution algorithm(QWPEA)and power law entropy(PLE)*** method is composed of preset move and autonomous coordination stages for satisfying non-repeated coverage,connectedness,and energy balance of sink layer critical requirements,which is actualized to cover sensors layer in large-scale outside wireless sensor networks(WSNs).Simulation results show that the performance of the proposed technique is better than the existing related coverage technique.

关键词： wireless sensor network(WSN) coverage multi-unmanned aerial vehicle(MUAV) heterogeneous sink node quantum wolf pack evolution algorithm(QWPEA) power law entropy(PLE)