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Effect of Nb addition on microstructure and mechanical properties of 25CrNiMoV(DZ2)steel for high-speed railway axles

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Journal of Iron and Steel Research International 2022年第5期29卷 802-809页

作者： Jin-wen Zhang yan-guang cao Cheng-guo Zhang Zhao-dong Li Wen-xian Wang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Technology Center Taiyuan Iron and Steel(Group)Co.Taiyuan030003ShanxiChina Department of Structural Steels Central Iron and Steel Research InstituteBeijing100081China Locomotive and Car Research Institute China Academy of Railway Sciences Corporation LimitedBeijing100081China

The microstructure,precipitates and properties of 25CrNiMoV(DZ2)steel for high-speed railway axles with different Nb contents were investigated by means of optical microscopy,scanning electron microscopy,electron back-scattering diffraction,transmission electron microscopy and physicochemical phase *** results show that the grain size of the original austenite of the test steels decreases from 20.5 to 14.2 and 10.8μm after adding 0.026 and 0.039 wt.%Nb to a 25CrNiMoV steel,***,the block width of the tempered martensite in the test steels is refined from 1.91 to 1.72 and 1.60µm,***-type precipitates in 25CrNiMoV steel are mainly VC,while(Nb,V)C gradually precipitates when Nb is microalloyed,and the amount of precipitates increases with increasing Nb *** strengthening mechanism analysis,it is found that grain refinement strengthening is the primary way to increase the *** improvement in the yield strength with increasing Nb content is attributed to a significant increase in precipitation strengthening,grain refinement strengthening and dislocation strengthening.

关键词： High-speed railway axle steel Nb microalloying Precipitate Strengthening mechanism

Application of internal fixation of steel-wire limited loop in early Achilles tendon rupture

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Asian Pacific Journal of Tropical Medicine 2013年第11期6卷 902-907页

作者： Zhe Chen Jia-Sen Wei Zhao-yang Hou Jiong Hu yan-guang cao Qi-Xin Chen Department of Orthopaedics The Second Affiliated Hospital of Zhejiang Chinese Medical University Department of Orthopaedics The Second Affiliated Hospital of Zhejiang University School of Medicine

Objective:To explore the clinical effect and safety of internal fixation of steel-wire limited loop in early Achilles tendon ***:Seventy-six patients respectively with early transected and avulsed types of Achilles tendon rupture were selected and treated with internal fixation of steel-wire limited *** patients began to take exercise for their lower limbs through continous passive motion as early as possible after surgical repair,and the loops were removed after 3-5 *** months later,the condition of complications including Achilles tendon re-rupture,wound fistula,wound infection and skin necrosis,cutaneous sensation in sural nerve dominance region,time back to preinjury work or learning as well as time to physical activities were *** year later,the therapeutic effect was evaluated,and the maximum circumferences of bilateral legs and raptured plane circumferences of Achilles tendon were ***:The wound of all patients healed well,no complications like Achilles tendon re-rupture,wound fistula,wound infection and skin necrosis occured,and the cutaneous sensation in sural nerve dominance region was *** mean time back to preinjury work or learning as well as to pysical activities of all patients were respectively 10 and 22 *** out of 76 patients(92.1%) achieved an excellent effect,and 6(7.9%) good *** excellent and good rate came up to 100%.The maximum circumference in the affected leg decreased to 2 mm averagely compared with the offside,while the ruptured plane circumferences of Achilles tendon in the affected side increased to 2.2 mm compared with the ***:Kor early Achilles tendon rupture,internal fixation of steel-wire limited loop can recover the ankle function better,return to the preinjury state in the shortest lime,and has few complications.

关键词： Achilles tendon rupture Steel-wire limited loop Internal fixation Ankle function

Pharmacokinetic-pharmacodynamic modeling of telmisartan using an indirect response model in spontaneously hypertensive rats

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Acta Pharmacologica Sinica 2007年第5期28卷 738-743页

作者： Kun HAO,Yuan-cheng CHEN,yan-guang cao,Dan YU,Xiao-quan LIU~2,guang-ji WANGKey Laboratory of Drug Metabolism and Pharmacokinetics,China Pharmaceutical University Nanjing 210009,China KeyLaboratoryofDrugMetabolismandPharmacokinetics ChinaPharmaceuticalUniversityNanjing210009China

Aim:To investigate the pharmacokinetic (PK) and the pharmacodynamic (PD)properties of telmisartan in spontaneously hypertensive (SH) rats using an indi-rect response and effect-compartment link models,and compare two PK-PD mod-els fitting ***:The SH rats received a single oral dose of 2,4,and 8mg/kg of *** plasma concentrations of telmisartan were determinedby the liquid chromatography-mass spectrum *** mean arterial bloodpressure was measured to characterize the pharmacodynamics of telmisartan bytail-cuff *** relationship for the telmisartan concentration-hypoten-sive effect in the SH rats was characterized using an indirect response ***:The PK parameters showed dose proportionality,with a long terminalhalf-life of 16 h,a clearance of 0.15 ***-1·h-1,and a volume of distribution of 5.36L·kg-1in the *** the indirect response PD model,the estimated Kinwere 36.6,34.1,and 32.8%·h-1,Koutwere 36.7,34.6,and 31.9·h-1;the IC50values were 86.2,95.8,and 91.1 ng·mL-1;and the area under the effect curve (AUEC) were 762.8,1490.5,and 2086.2 mmHg·h at three doses,*** the effect-compart-ment model,the Keowere 29.4,33.8,and 28.7·h-1;the IC50values were 78.2,85.7,and80.9 ng·mL-1,and the AUEC were 781.5,1602.8,and 2215.7 mmHg·h at three doses,***:According to Akaike’s information criterion values,theproposed indirect response model provided a more appropriate and good-fittingPK/PD characterization of telmisartan than the effect-compartment link model inSH rats.

关键词： telmisartan pharmacokinetic-pharmacodynamic indirect response model effectcompartment link model spontaneouslyhypertensive rats

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基于模糊神经网络的电梯系统交通模式识别

系统工程学报 2001年第6期16卷 418-424页

作者：宗群尚晓光严明曹燕飞岳有军雷小锋天津大学电气自动化与能源工程学院天津300072

介绍采用模糊神经网络进行电梯群控系统交通模式识别的方法 .用 3步混合训练方法对用于模式识别的两个模糊神经网络进行训练 .测试结果表明此方法可以准确地辨识出各种交通模式所占的比例 ,可以指导群控器优化派梯策略 ,提高电梯群控系... 详细信息

介绍采用模糊神经网络进行电梯群控系统交通模式识别的方法 .用 3步混合训练方法对用于模式识别的两个模糊神经网络进行训练 .测试结果表明此方法可以准确地辨识出各种交通模式所占的比例 ,可以指导群控器优化派梯策略 ,提高电梯群控系统的服务性能 .

关键词：电梯群控系统交通模式识别模糊神经网络现代化建筑

Controlled synthesis and optical properties of Ce^(3+)/Tb^(3+) co-doped BaGdF_5 nanocrystals

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Rare Metals 2015年第9期34卷 673-678页

作者： Chun-yan cao An Xie Xiao-guang Yu College of Mathematics and Physics Jinggangshan University School of Materials Science and Engineering Xiamen University of Technology

Based on a hydrothermal method, the Ce3+/Tb3+ co-doped Ba Gd F5 nanocrystals were synthesized by controlling the introduction concentration of Ba2+ and Gd3+. The samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FESEM) images, photoluminescence(PL) excitation, and emission spectra, as well as the photoluminescence dynamic decay curves. With the increase of the Ba2+ concentration in the synthesis procedure, the positions of diffraction peaks of XRD patterns move toward lower degree, and the case of the samples synthesized with the increase of the Gd3+ concentration is contrary, which consists well with each other. The FE-SEM images suggest that the BaGdF5 nanocrystals are in spherical morphology,and the average diameters decrease with the increase of Ba2+ or Gd3+ concentration. For the 4f–5d transition of Ce3+ is sensitive to the environment of local lattice, the PL excitation and emission spectra of the samples are different. The 4f–4f transition of Tb3+ also presents different optical properties in different host lattices. The variations of the optical properties of Ce3+ and Tb3+ as well as the lifetime of the 5D4+7F5 emission of Tb3+ are also consistent well with each other in the two series of samples.

关键词： Hydrothermal synthesis Optical properties Nanocrys

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利用双口RAM实现的高速数据采集系统

天津纺织工学院学报 1999年第5期18卷 78-82页

作者：林广艳曹晓英天津纺织工学院计算中心天津300160 天津纺织工学院图书馆天津300160

直接与微处理器或微型计算机连接的模－数转换系统对模拟信号的最大采样频率通常都有非常严格的限制．如果在采集数据期间先将采集到的数据暂存到外部ＲＡＭ，稍后再传送给微处理器，则可有效地提高采样频率．本文提出了一种利用高速的... 详细信息

直接与微处理器或微型计算机连接的模－数转换系统对模拟信号的最大采样频率通常都有非常严格的限制．如果在采集数据期间先将采集到的数据暂存到外部ＲＡＭ，稍后再传送给微处理器，则可有效地提高采样频率．本文提出了一种利用高速的双口ＲＡＭ来实现模－数转换的系统，该系统在１５ＭＨｚ的采样频率下运行可靠且通用性强．

关键词：数据采集双口RAM 模-数转换器采样频率

Can patients with mild non-neoplastic lesions diagnosed at baseline screening be safely exempt from surveillance: evidence from multicenter community-based cohorts

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Science China Life Sciences 2025年第1期 263-271页

作者： Siyi He Zhiyi Zhang Guohui Song Zhenhai Wang Chunyun Dai Shipeng yan Kun Jiang Bingbing Song He Li Maomao cao Dianqin Sun Fan yang Xinxin yan Shaoli Zhang Yi Teng Qianru Li Changfa Xia Wanqing Chen Office of Cancer Screening National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College Department of Gastroenterology Gansu Wuwei Tumor Hospital Cixian Cancer Institute Linzhou Cancer Hospital Center for Disease Control and Prevention of Sheyang County Department of Cancer Prevention and Control Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South University Luoshan Center for Disease Control and Prevention Office for Cancer Control and Research Affiliated Cancer Hospital of Harbin Medical University

Surveillance recommendations for gastric cancer（GC） in current guidelines focused on advanced precancerous lesions and were based on precise diagnosis of severity/extent of baseline lesions. We aimed to develop a less endoscopy-related equipment-dependent risk-stratification tool, and assessed whether mild-precursor-lesion patients can be safely exempt from surveillance. In the multicenter communitybased cohort, 75,051 participants receiving baseline endoscopy were enrolled during 2015–2017 and followed-up until 2021. Cumulative incidence rates（CIRs） of GC for precancerous-conditions were calculated by Kaplan-Meier method and compared by Log-rank tests. Mixedeffects Cox regression models were used to detect potential factors for progression towards GC. A risk score was calculated as counts of selected factors. An independent cohort, including 26,586 participants was used for external validation. During a median follow-up of 6.25 years, CIRs of GC were 0.302%, 0.436%, and 4.756% for normal group, non-neoplastic（atrophic gastritis/intestinal metaplasia） and neoplastic lesions（low-grade/high-grade dysplasia）, respectively(Ptrend<0.001). Four predictors, including male, ≥60 years, smoking, and limited vegetable consumption, were selected for risk-stratification. High-risk patients（≥3 risk factors） with non-neoplastic lesions showed higher GC risks（adjusted HR=7.73, 95%CI: 4.29–13.92）, and their four-year CIR reached the one-year CIR of neoplastic lesions. Further categorizing non-neoplastic lesions by histological grade, both patients with moderate-to-severe lesions（aHR=3.07, 95%CI: 1.67–5.64） and high-risk patients with mild lesions（aHR=7.29, 95%CI: 3.58–14.86） showed higher risks. Consistent trends were observed in validation cohort. High-risk mild-precursor-lesion patients should receive surveillance within 3–5 years after baseline screening. Our study provides evidence on supplementing current guideline recommendations.

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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu Liang Ni-Hui Zhang Zhi-Lai Zhan guang-Lu Chang yan Gao Xia Li Wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

Burning products of TA15 titanium alloy by friction oxygen concentration method

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Rare Metals 2018年第11期37卷 952-960页

作者： Nan Sui guang-Bao Mi Meng-Qi yan Jing-Xia cao Xu Huang Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys AECC Beijing Institute of Aeronautical Materials

The microstructural characteristics, elemental distribution law and microscopic formation mechanism of the burning products of TA15 titanium alloy were investigated by friction oxygen concentration method, associated with in situ observation, X-ray diffraction(XRD),scanning electron microscopy(SEM) and energy-dispersive spectroscopy(EDS) analyses, providing the thoughts to improve fireproof property. The results show that, when the friction contact pressure(p) is 0.20 MPa and oxygen concentration of premixed air flow(c) is 60 vol%, TA15 titanium alloy produces violent sparks and presents dazzling white light during combustion. The generated products after burning are mainly TiOand small amount of AlOoxides. Four distinct zones form from the combustion surface to the alloy matrix, and they are in the sequence of combustion zone, fusion zone, heat-affected zone and transition zone. Further, combustion zone is composed of TiOand A1203 compounds, containing obvious cracks. In the fusion zone, discontinuous oxygenrich Al-based solid solution forms, and the elemental distribution has strong volatility. In the heat-affected zone,there are abundant of Ti-based solid solution and small amount of Al-and Mo-based solid solution. Transition zone is made of lamellar structure. Two technical approaches are given to prevent oxygen diffusion inside the reaction zone and reaction-affected zone. On the one hand,the content of Al is designed as the upper limit of alloy composition; on the other hand, fireproof coatings are deposited on the surface of the alloy.

关键词： Friction oxygen concentration method TA15 titanium alloy Burning products Microstructure Titanium fire