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Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu Zhenyu sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

芩楼清利丸对变态反应性接触性皮炎大鼠血清及皮损炎性因子的影响

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中华中医药杂志 2018年第12期33卷 5592-5595页

作者：梅沉成何文凤李瑞婷孙超逸范欢任映王蓬文屈双擎张云璧北京中医药大学北京100029 北京市房山区中医院皮肤科北京102488 郑州市中医院皮肤科郑州450000 北京中医药大学东直门医院皮肤科北京100700 北京中医药大学东直门医院中医内科学教育部重点实验室北京100700

目的:探讨芩楼清利丸治疗变态反应性接触性皮炎(ACD)的可能作用机制。方法:将40只雄性SD大鼠随机分为空白组、模型组、治疗组和阳性对照组,各10只。除空白组外,其余3组采用0.1%二硝基氯苯溶液(DNCB)分别致敏2次建立ACD模型。治疗组将芩... 详细信息

目的:探讨芩楼清利丸治疗变态反应性接触性皮炎(ACD)的可能作用机制。方法:将40只雄性SD大鼠随机分为空白组、模型组、治疗组和阳性对照组,各10只。除空白组外,其余3组采用0.1%二硝基氯苯溶液(DNCB)分别致敏2次建立ACD模型。治疗组将芩楼清利丸溶于纯净水中灌胃给药,阳性对照组将盐酸西替利嗪片溶于纯净水中灌胃给药,模型组采用纯净水灌胃,每天2次,共2周。实验2周后取材前评估皮损疗效;取材后,通过HE染色观察各组大鼠皮肤的病理变化;采用ELISA检测各大鼠血清中白细胞介素-4(IL-4)、肿瘤坏死因子-α(TNF-α)以及皮损组织中白细胞三稀B4(LTB4)水平;采用实时荧光定量PCR检测皮损中白细胞三烯受体1(BLT1)、半胱氨酸天冬氨酸蛋白酶-14(Caspase-14)表达情况。结果:治疗组、阳性对照组与模型组相比,皮损红斑、水肿、丘疹、表皮剥脱等均显著减轻(P<0.05)。病理结果提示,两组大鼠背部皮肤的角质层变薄,表皮层、真皮层内炎症细胞浸润较模型组显著减少。模型组LTB4、TNF-α、Caspase-14 mRNA的表达水平较空白组显著上升(P<0.01,P<0.05),治疗组和阳性对照组LTB4较模型组显著下降(P<0.05,P<0.01),TNF-α、Caspase-14 mRNA的表达水平较模型组也显著下降(P<0.01,P<0.05)。模型组大鼠皮肤BLT1 mRNA的表达水平较空白组显著降低(P<0.01),阳性对照组和治疗组的表达水平较模型组上升,但差异无统计学意义。各组大鼠血清中IL-4水平无明显差异。结论:芩楼清利丸治疗ACD的作用机制可能与调节血清及皮损中的相关炎性因子及促进表皮屏障恢复有关。

关键词：芩楼清利丸变态反应性接触性皮炎白细胞三稀B4 肿瘤坏死因子-α 半胱氨酸天冬氨酸蛋白酶-14 炎性因子

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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A kinetic study and factor analysis of solar thermochemical membrane reactors for syngas production

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Science China Technological Sciences 2025年第1期 207-221页

作者： Jiaxin XING chao XU Xiangyu sun Xin XIA Fei JIN Qiongqiong JIANG Jiale GAO Key Laboratory of Power Station Energy Transfer Conversion and System of MOE School of Energy Power and Mechanical EngineeringNorth China Electric Power University Department of Chemistry University College London School of Chemistry and Chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion TechnologyState Ethnic Affairs CommissionNorth Minzu University

Solar thermochemical conversion technologies are promising for effectively utilizing solar energy by capturing the full spectrum of solar radiation. To overcome the challenges of low energy conversion efficiency and intermittency faced by solar thermochemical conversion, these technologies can be effectively integrated with membrane reactor technology. Although the performance of solar thermochemical membrane reactors has been experimentally tested, the chemical reactions and oxygen transport mechanisms during the energy conversion process remain poorly understood. This study introduces a resistance network model to elucidate the interactions between interfacial reactions and bulk diffusion during simultaneous oxidationreduction reactions on both sides of the membrane. We analyzed the oxygen flux of the membrane reactor under various operating conditions using this model to identify the reaction/transport-limiting side of the overall process. The most effective solar membrane reactor configuration utilizes natural gas and CO2, facilitating clean conversion of fossil fuels with significant advantages in fuel production and energy efficiency. Introducing CH4lowers the overall reaction temperature, maintains low oxygen partial pressure on the sweep side, and produces a synthesis gas with a 2:1 H2/CO molar ratio. Finally, a sensitivity analysis was used to explore the relationship between overall fuel production performance and operational parameters,highlighting the critical role of this research in enhancing the reaction and transport performance of membrane reactors and advancing the development of solar-driven thermochemical fuel production technologies.

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Distribution and mode of occurrence of uranium in bottom ash derived from high-germanium coals

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Journal of Environmental Sciences 2016年第5期28卷 91-98页

作者： yinglong sun Guangxia Qi Xuefei Lei Hui Xu Lei Li chao Yuan yi Wang Department of Environmental Engineering School of Environment Tsinghua University Department of Environmental Science and Engineering School of Food and Chemical EngineeringBeijing Technology and Business University

The radioactivity of uranium in radioactive coal bottom ash（CBA） may be a potential danger to the ambient environment and human health. Concerning the limited research on the distribution and mode of occurrence of uranium in CBA, we herein report our investigations into this topic using a number of techniques including a five-step Tessier sequential extraction, hydrogen fluoride（HF） leaching, Siroquant（Rietveld） quantification, magnetic separation, and electron probe microanalysis（EPMA）. The Tessier sequential extraction showed that the uranium in the residual and Fe–Mn oxide fractions was dominant（59.1%and 34.9%, respectively）. The former was mainly incorporated into aluminosilicates,retained with glass and cristobalite, whereas the latter was especially enriched in the magnetic fraction, of which about 50% was present with magnetite（Fe_3O_4） and the rest in other iron oxides. In addition, the uranium in the magnetic fraction was 2.6 times that in the non-magnetic fraction. The experimental findings in this work may be important for establishing an effective strategy to reduce radioactivity from CBA for the protection of our local environment.

关键词： Coal bottom ash Uranium Radioactivity Tessier sequential extraction Magnetic separation

Hot Compression Behavior and Tensile Property of a Novel Ni-Co-Based Superalloy Prepared by Electron Beam Smelting Layered Solidification Technology

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 283-292页

作者： Yong-chao Gai Rui Zhang Chuan-Yong Cui Zi-Jian Zhou yi Tan yi-Zhou Zhou Xiao-Feng sun Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The hot compression behavior and tensile strength after compression of a new Ni-Co-based superalloy produced using electron beam smelting layered(EBSL)solidification technology were *** compression tests were performed at temperatures of 1120℃and 1150℃,with strain rates of 1 s^(-1) and 0.01 s^(-1),reaching a true strain of *** strength was evaluated at room *** results revealed that this EBSL technology accelerates dynamic recrystallization(DRX),without compromising the strength of alloy.A significant correlation between the volume fraction of DRX and the strain rate was observed,with higher fractions at lower strain rates,leading to higher tensile ***,at the same strain rate,the specimens compressed at 1120℃exhibited higher tensile strength due to undissolvedγ′*** solution and aging heat treatment,the alloy maintained high tensile *** results suggested that the EBSL Ni-Co-based superalloy offers excellent prospects for practical applications.

关键词： Ni-Co-based superalloy Hot deformation Electron beam smelting Tensile strength

Flexible molecules dedicate to release strain of inverted inorganic perovskite solar cell

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Journal of Energy Chemistry 2025年第1期100卷 87-93页

作者： Hongrui sun Sanlong Wang Pengyang Wang Yali Liu Shanshan Qi Biao Shi ying Zhao Xiaodan Zhang Institute of Photoelectronic Thin Film Devices and Technology Renewable Energy Conversion and Storage Center State Key Laboratory of Photovoltaic Materials and CellsNankai University Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin Haihe Laboratory of Sustainable Chemical Transformations Engineering Research Center of Thin Film Photoelectronic Technology of Ministry of Education Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)

The tensile strain in inorganic perovskite films induced by thermal annealing is one of the primary factors contributing to the inefficiency and instability of inorganic perovskite solar cells （IPSCs）,which reduces the defect formation ***,a flexible molecule 5-maleimidovaleric acid （5-MVA） was introduced as a strain buffer to release the residual strain of *** anhydride and carboxyl groups in 5-MVA interact strongly with the uncoordinated Pb2+through Lewis acid-base reaction,thus tightly“pull”the perovskite *** in-between soft carbon chain increased the structural flexibility of CsPbI2.85Br0.15perovskite materials,which effectively relieved the intrinsic internal strain of CsPbI2.85Br0.15,resisted the corrosion of external strain,and also reduced the formation of defects such as VIand *** addition,the introduction of 5-MVA improved crystal quality,passivated residual defects,and narrowed energy level ***,power conversion efficiency （PCE） of NiOxbased inverted IPSCs increased from 19.25% to 20.82% with the open-circuit voltage enhanced from 1.164 V to 1.230 *** release of strain also improved the stability of CsPbI2.85Br0.15perovskite films and devices.

关键词： Inverted inorganic perovskite solar cells Flexible molecules Strain release Crystallization Energy barrier High PCE

EDGE-ORIENTED HEXAGONAL ELEMENTS

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Journal of Computational Mathematics 2007年第4期25卷 430-439页

作者： chao Yang Jiachang sun Parallel Computing Lab. Institute of Software Chinese Academy of Sciences Beijing 100080 China

In this paper, two new nonconforming hexagonal elements are presented, which are based on the trilinear function space Q1^（3） and are edge-oriented, analogical to the case of the rotated Q1 quadrilateral element. A priori error estimates are given to show that the new elements achieve first-order accuracy in the energy norm and second-order accuracy in the L^2 norm. This theoretical result is confirmed by the numerical tests.

关键词： Nonconforming finite element method Hexagonal element Q1 element.

Automatic localization of macular area based on structure label transfer

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International Journal of Ophthalmology(English edition) 2018年第3期11卷 422-428页

作者： Xiao-Xin Guo Qun Li chao sun yi-Nan LU Key Laboratory of Symbol Computation and Knowledge Engineering of Ministry of Education Changchun130012 Jilin Province China College of Computer Science and Technology Jilin University Changchun 130012 Jilin Province China

AIM： To explore feasibility and practicability of macula localization independent of macular morphological features. METHODS： A novel method was proposed to identify macula in fundus images by using structure label transfer. Its main idea was to match a processed image with the candidate images with known structures, and then transfer the structure label representing the macular to the processed image as a result of macula localization. In this way, macula localization couldn＇t be influenced by lesion or other interference any more. RESULTS： The average success rate in four datasets was 98.18%. For accuracy, the average error distance in four datasets was 0.151 optic disc diameter （ODD）. Even for severe lesion images, the proposed method can still maintain high success rate and high accuracy, e.g., 95.65% and 0.124 ODD in the case of STARE dataset, respectively, which indicated that the proposed method was highly robust and stable in the complicated situations. CONCLUSION： The proposed method can avoid the interference of lesion to macular morphological features in macula localization, and can locate macula with high accuracy and robustness, verifying its feasibility.

关键词： fundus image optic disc macula structurelabel transfer