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China Foundry 2024年第1期21卷 11-19页

作者： Wen-ning Liu Wei Zhang Peng-yue wang Yi-xian Liu xiang-yi Jiao Ao-xiang Wan Cheng-gang wang Guo-dong Tong shou-mei Xiong School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Tsinghua UniversityBeijing 100084Beijing China FAW Group Co. Ltd.Changchun 130013China China FAW Foundry Co. Ltd.Changchun 130013China

The effect of slow shot speed on externally solidified crystal(ESC),porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy was investigated by optical microscopy(OM),scanning electron microscopy(SEM)and laboratory computed tomography(CT).Results showed that the newly developed AlSi9MnMoV alloy exhibited improved mechanical properties when compared to the AlSi10MnMg *** AlSi9MnMoV alloy,which was designed with trace multicomponent additions,displays a notable grain refining effect in comparison to the AlSi10MnMg *** elements Ti,Zr,V,Nb,B promote heterogeneous nucleation and reduce the grain size of primaryα-*** a lower slow shot speed,the large ESCs are easier to form and gather,developing into the dendrite net and *** an increase in slow shot speed,the size and number of ESCs and porosities significantly *** addition,the distribution of ESCs is more dispersed and the net-shrinkage *** tensile property is greatly improved by adopting a higher slow shot *** ultimate tensile strength is enhanced from 260.31 MPa to 290.31 MPa(increased by 11.52%),and the elongation is enhanced from 3.72%to 6.34%(increased by 70.52%).

关键词： hypoeutectic Al-Si alloy high pressure die casting porosity externally solidified crystal tensile property

Microstructural evolution and mechanical properties of duplex-phase Ti6242 alloy treated by laser shock peening

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Transactions of Nonferrous Metals Society of China 2024年第8期34卷 2521-2532页

作者： Pu-ying SHI xiang-hong LIU Yong REN Zeng TIAN Feng-shou ZHANG Wei-feng HE Institute of Aeronautics Engine School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710049China Western Superconducting Technologies Co. Ltd.Xi’an 710018China School of Aeronautical Engineering Air Force Engineering UniversityXi’an 710038China

The effects of laser shock peening(LSP)on the microstructural evolution and mechanical properties of the Ti6242 alloy,including the residual stress,surface roughness,Vickers microhardness,tensile mechanical response,and high-cycle fatigue properties,were *** results showed that the LSP induced residual compressive stresses on the surface and near surface of the *** maximum surface residual compressive stress was−661 MPa,and the compressive-stress-affected depth was greater than 1000μ*** roughness and Vickers micro-hardness increased with the number of shocks,and the maximum hardness-affected depth was about 700μm after three LSP *** enhanced the fraction of low-angle grain boundaries,changed the grain preferred orientations,and notably increased the pole density ofαphase on the near surface from 2.41 to *** surface hardness values of the LSP samples increased with the increase of the number of shocks due to work hardening,while the LSP had a limited effect on the tensile *** high-cycle fatigue life of the LSP-treated sample was significantly enhanced by more than 20%compared with that of the untreated sample,which was caused by the suppression of the initiation and propagation of fatigue cracks.

关键词： duplex-phase Ti6242 alloy surface modification laser shock peening gradient microstructure high-cycle fatigue properties

Application of ^(18)F-fluorodeoxyglucose positron emission tomography/computed tomography imaging in recurrent anastomotic tumors after surgery in digestive tract tumors

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2474-2483页

作者： Deng-Feng Ge Hao Ren Zi-Chen Yang shou-xiang Zhao Zhen-Ting Cheng Da-Da Wu Bin Zhang Department of Cardiothoracic Surgery Nanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina Department of Gastrointestinal Surgery Shanghai Sixth People’s HospitalShanghai 250063China

BACKGROUND This study was to investigate the application value of whole-body dynamic ^(18)F-fluorodeoxyglucose(FDG)positron emission tomography/computed tomogra-phy(PET/CT)imaging in recurrent anastomotic tumors of digestive tract after gastric and esophageal cancer *** patients with gastric and esophageal cancer have a high risk of tumor recurrence,and traditional imaging methods have certain limitations in early detection of recurrent ***-body dynamic ^(18)F-FDG PET/CT imaging,due to its high sensitivity and specifi-city,can provide comprehensive information on tumor metabolic activity,which is expected to improve the early diagnosis rate of postoperative recurrent tumors,and provide an important reference for clinical treatment *** A retrospective analysis was performed on 53 patients with upper digestive tract tumors after operation and systemic dynamic ^(18)F-FDG PET/CT imaging indi-cating abnormal FDG uptake by anastomosis,including 29 cases of gastric cancer and 24 cases of esophageal *** to the follow-up results of gas-troscopy and other imaging examinations before and after PET/CT examination,the patients were divided into an anastomotic recurrence group and anastomotic inflammation *** multi-parameter analysis software was used to obtain the metabolic rate(MRFDG),volume of distribution maximum(DVmax)of anastomotic lesions,and MRmean and DVmean of normal liver *** lesion/background ratio(LBR)was calculated by dividing the MRFDG and DVmax of the anastomotic lesion by the MRmean and DVmean of the normal liver tissue,respectively,to obtain LBR-MRFDG and *** independent sample t test was used for statistical analysis,and a receiver operating characteristic curve was used to analyze the differential diagnostic efficacy of each parameter for anastomotic recurrence and *** The dynamic ^(18)F-FDG PET/CT imaging parameters MRFDG,DVmax,LBR-MRFDG,and LBR-DVmax of post

关键词： Gastric cancer Esophageal cancer Anastomosis Dynamic positron emission tomography Differential diagnosis Metabolic rate

Soluble proteins from Trichinella spiralis adult worm inhibits allergic specific Th2 response

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Soluble proteins from Trichinella spiralis adult worm inhibi...

Coherent optical frequency transfer via 972-km fiber link

中国动物学会寄生虫学专业委员会第十届全国寄生虫学青年工作者学术研讨会

作者： Xiaodi Yang li-Yuan wang Xiao-li wang Hui Zhang Qiao-li Xie Xiao-lin Li shou-xiang wang Feng Yuan Yuan-yuan Sun Mu-zi Zhao Hong-ghuang Zhang Fang Qiang Department of Microbiology and Parasitology Anhui Key Laboratory of Infection and Immunity The Scientific Research Innovation Team Project of Anhui Colleges and Universities (2016-40) Bengbu Medical College

Objectives: In order to ascertain whether parasite-derived proteins could inhibit the allergic specific Th2 response, we applied soluble products from Trichinella spiralis adult worm(ASP) to asthma model mice simultaneously with OVA challenge, after which we assessed the OVA-specific Th2 response. Methods: BALB/c mice were sensitized with intraperitoneal injected OVA-alum and challenged with aerolized OVA. Mice were given soluble products from T. spiralis adult worm(ASP). Lung histopathology, cellularity of bronchoalveolar lavage(BAL) and eosinophil peroxidase activity in lung were evaluated. Cytokines in BAL were also measured. Results: Treatment with T. spiralis ASP treatment significantly ameliorated the severity of OVA-alum induced asthma as evidenced by reduction of the recruitment of inflammatory cells into the airway, and in particular, macrophages, neutrophils, and lymphocytes. Our results demonstrated that ASP are able to modulate the potent pro-inflammatory response induced by OVA-alum, mainly through the down-regulation of Th2(IL-4, IL-5) and up-regulation of Treg(TGF-β) cytokines in BAL. Additionally, IL-10, as we observed, was not significantly increased in the ASP-treated mice than those of mice non-treated. Conclusions: Our results suggest that helminths suppress the development of asthma by soluble substances that modulate allergic responses. The identification of these products may lead to the design of novel therapeutic intervention strategies for the treatment of asthma.

关键词： allergy Trichinella spiralis inhibition soluble antigen

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Chinese Physics B 2024年第2期33卷 277-282页

作者：邓雪张翔臧琦焦东东王丹刘杰高静许冠军董瑞芳刘涛张首刚 National Time Service Centre Chinese Academy of SciencesXi’an 710600China Key Laboratory of Time Reference and Application Chinese Academy of SciencesXi’an 710600China School of Communications and Information Engineering and School of Artificial Intelligence Xi’an University of Posts and TelecommunicationsXi’an 710121Chin

We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated *** of employing a phase discriminator and a phase locking loop in the conventional active phase control scheme,the passive phase noise cancellation is realized by feeding double-trip beat-note frequency to the driver of the acoustic optical modulator at the local *** passive scheme exhibits fine robustness and reliability,making it suitable for long-distance and noisy fiber *** optical regeneration station is used in the link for signal amplification and cascaded *** phase noise cancellation and transfer instability of the 972-km link is investigated,and transfer instability of 1.1×10^(-19)at 10^(4)s is *** work provides a promising method for realizing optical frequency distribution over thousands of kilometers by using fiber links.

关键词： optical frequency transfer fiber link phase noise cancellation

中东Z油田一开地层可钻性预测和个性化PDC钻头的应用

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石油工业技术监督 2024年第2期40卷 37-42页

作者：寿翔成都百施特金刚石钻头有限公司四川成都610041

中东Z油田一开井段井眼尺寸大、井段长、地质条件复杂、钻头选型不合理,探井一般需要20多只钻头才能完钻,钻井周期长、成本高,严重影响全井的建井周期和油田的大规模开发。利用测井数据,使用地层可钻性模型预测了一开井段的地层可钻性剖... 详细信息

中东Z油田一开井段井眼尺寸大、井段长、地质条件复杂、钻头选型不合理,探井一般需要20多只钻头才能完钻,钻井周期长、成本高,严重影响全井的建井周期和油田的大规模开发。利用测井数据,使用地层可钻性模型预测了一开井段的地层可钻性剖面,显示出该地层可钻性波动频繁、软硬交错显著、非均质性强。在此基础上设计了将强稳定性、攻击性和水利设计相结合的个性化609.6 mm MS1963UV型PDC钻头。在后续现场试验中,该型钻头突破性地实现了1只牙轮钻头+1只PDC钻头钻完一开井段,提速最高达109.77%,钻头每米成本降幅最高达32.13%。实践证明,区块可钻性预测结果较为符合实际,个性化设计的PDC钻头能够很好地适应目标井段地层,为进一步优化改进钻头设计和Z油田的持续提速提效提供了有益的参考。

关键词：可钻性测井资料 PDC钻头个性化设计

不同地理种源杉木细根呼吸及其与形态、化学性状的关系研究

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林业科学研究 2024年第4期37卷 148-156页

作者：寿烨王兵牛香宋希强许庭毓王以惠海南大学热带农林学院海南海口570228 中国林业科学研究院森林生态环境与自然保护研究所北京100091 国家林业和草原局森林生态环境重点实验室北京100091 江西大岗山森林生态系统国家野外科学观测研究站江西分宜338033 海南省热带特色林木花卉生物学重点实验室海南海口570228

[目的]:分析不同种源杉木细根呼吸及其形态、化学性状的差异,增进对根系呼吸与其他根系特征之间联系的理解。[方法]:以江西大岗山杉木种源同质园的10个种源为对象,对杉木细根呼吸及其形态、化学性状的种源间差异以及各指标间的关联性开... 详细信息

[目的]:分析不同种源杉木细根呼吸及其形态、化学性状的差异,增进对根系呼吸与其他根系特征之间联系的理解。[方法]:以江西大岗山杉木种源同质园的10个种源为对象,对杉木细根呼吸及其形态、化学性状的种源间差异以及各指标间的关联性开展了研究。[结果]:杉木细根呼吸、细根形态性状和化学性状的种源间变异系数分别为40.42%、18.82%~22.88%、7.84%~19.73%。不同种源杉木细根呼吸存在显著差异(p<0.05),浙江开化种源细根呼吸速率最大(7.97±1.08 nmol·g^(−1)·s^(−1)),重庆永川种源最小(1.63±0.40 nmol·g^(−1)·s^(−1));不同种源杉木细根形态性状、化学性状也呈显著差异(p<0.05),福建建瓯种源具有最大的比根长(579.17±17.11 cm·g^(−1))、根比表面积(139.97±10.18 cm^(2)·g^(−1));浙江开化种源具有最大的根C含量(458.12±5.40 g·kg^(−1))、N含量(10.58±0.02 g·kg^(−1))、N:P(17.85±0.29);江西分宜本地种源具有最大的根组织密度(0.62±0.12 g·cm^(−3))、以及最小的根N含量(6.38±0.11 g·kg^(−1))、C:P(481.39±8.94)、N:P(10.64±0.41)。对杉木细根呼吸及其形态、化学性状间的权衡关系分析表明,细根呼吸与根系氮含量之间呈显著正相关(p<0.05),与比根长、根组织密度的相关性较小。[结论]:不同地理种源杉木细根对环境变化的适应策略存在差异,细根呼吸与根形态性状的关联较小,主要与根N含量关系密切。

关键词：杉木地理种源根呼吸根性状

聚氯乙烯火灾烟气环境中无铅焊料腐蚀动力学预测模型

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Transactions of Nonferrous Metals Society of China 2024年第7期34卷 2304-2312页

作者：李倩林锦赵梦珂黎昌海陆守香中国科学技术大学火灾科学国家重点实验室合肥230026

采用质量损失法研究聚氯乙烯火灾烟气环境中283.15~323.15 K温度范围内无铅Sn-3.0Ag焊料的腐蚀动力学、表面微观结构和腐蚀机理。结果表明,随着温度从283.15 K升高到323.15 K,Sn-3.0Ag焊料的质量损失从(22.09±2.01)g/m^(2)增加到(44.66... 详细信息

采用质量损失法研究聚氯乙烯火灾烟气环境中283.15~323.15 K温度范围内无铅Sn-3.0Ag焊料的腐蚀动力学、表面微观结构和腐蚀机理。结果表明,随着温度从283.15 K升高到323.15 K,Sn-3.0Ag焊料的质量损失从(22.09±2.01)g/m^(2)增加到(44.66±1.20)g/m^(2)。此外,腐蚀动力学符合阿伦尼乌斯定律。Sn-3.0Ag焊料表面腐蚀产物呈叠加生长趋势。在283.15 K,Sn-3.0Ag焊料的表面出现大量的腐蚀产物。Sn-3.0Ag无铅焊料的腐蚀过程为电化学腐蚀,阴极发生析氢和吸氧反应,阳极发生富锡相的溶解。腐蚀产物为Sn_(21)Cl_(16)(OH)_(14)O_(6)、SnO_(2)和SnO。

关键词：腐蚀预测模型 Sn-3.0Ag焊料火灾烟气温度

2A12/6061异种铝合金TIG搭接接头的疲劳性能

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材料热处理学报 2024年第2期45卷 195-203页

作者：赵平林王瑞杰刘国寿廖祥雲昆明理工大学机电工程学院昆明理工大学建筑工程学院

对3 mm厚的2A12/6061异种铝合金板材进行搭接钨极惰性气体保护焊(TIG),利用光学显微镜、显微硬度仪、扫描电镜和疲劳实验机等对接头的疲劳性能进行分析。在实验结果的基础上,对搭接试样建立有限元模型,采用热点应力法预测接头的疲劳寿命... 详细信息

对3 mm厚的2A12/6061异种铝合金板材进行搭接钨极惰性气体保护焊(TIG),利用光学显微镜、显微硬度仪、扫描电镜和疲劳实验机等对接头的疲劳性能进行分析。在实验结果的基础上,对搭接试样建立有限元模型,采用热点应力法预测接头的疲劳寿命,并与实验结果进行比较。结果表明:焊缝区组织为均匀的等轴晶,2A12侧焊缝与母材熔合较差,且与母材强度差异较大,导致2A12侧焊趾处更容易产生冶金缺陷和较大的应力梯度,进而加速疲劳裂纹的萌生;在不同载荷水平下,试件断裂位置均位于强度差异较大的2A12侧焊趾处,呈脆-塑性复合断裂特征,焊趾处冶金缺陷及焊缝局部强度差异为影响接头疲劳性能的主要因素。寿命预测结果表明:采用考虑板厚效应的热点应力法预测寿命准确,误差在两倍误差带内,采用IIW推荐的FAT40 S-N曲线是安全可靠的。

关键词：异种铝合金 TIG焊疲劳强度热点应力法疲劳寿命

氧化铜/羧基化碳纳米片修饰玻碳电极用于尿酸的灵敏检测

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化学研究与应用 2024年第7期36卷 1451-1457页

作者：利健文黄象金韦寿莲广东食品药品职业学院广东广州510520 肇庆市食品检验所广东肇庆526060 肇庆学院环境与化学工程学院广东肇庆526061 广东省环境健康与资源利用重点实验室广东肇庆526061

制备了氧化铜(CuO)纳米棒和羧基化碳纳米片(cCNSs)两种材料,并通过滴涂方式将其修饰在玻碳电极(GCE)表面,构建了一种用于检测尿酸(UA)的电化学传感器。采用扫描电镜(SEM)、X-射线衍射(XRD)和X射线光电子能谱(XPS)对所制备的材料进行表... 详细信息

制备了氧化铜(CuO)纳米棒和羧基化碳纳米片(cCNSs)两种材料,并通过滴涂方式将其修饰在玻碳电极(GCE)表面,构建了一种用于检测尿酸(UA)的电化学传感器。采用扫描电镜(SEM)、X-射线衍射(XRD)和X射线光电子能谱(XPS)对所制备的材料进行表征。通过微分脉冲伏安法(DPV)和循环伏安法(CV)研究了传感器的电化学性能。结果表明,CuO/cCNSs修饰电极对UA的氧化有很好的催化效果。与GCE电极相比,UA在CuO/cCNSs修饰电极上的峰电流增强了约122倍。在0.3~-30.0μmol·L^(-1)浓度范围内,UA的氧化峰电流与其浓度呈良好的线性关系,检出限为0.087μmol·L^(-1)。该传感器具有良好的选择性、重现性和稳定性,应用于人体尿样中UA的检测,加标回收率为83.2%~103%。

关键词：尿酸电化学传感器羧基化碳纳米片氧化铜