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Hot-deformation kinetics analysis and extrusion parameter optimization of a dilute rare-earth free magnesium alloy

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Journal of Magnesium and Alloys 2023年第9期11卷 3302-3322页

作者： Qinghang Wang Haowei Zhai Zhaoyang Jin Junjie He Qin yang {2. Liu Yulong Li Dao{3.n chen School of Mechanical Engineering Yangzhou UniversityNo.196 West Huayang RoadHangjiangYangzhou225127China School of Materials and Energy Yunnan UniversityKunming650599China Changan Auto Global R&D center Chongqing401120China College of Materials Science and Engineering Chongqing University of TechnologyChongqing400054China Department of Mechanical and Industrial Engineering Toronto Metropolitan University(formerly Ryerson University)TorontoON M5B 2K3Canada

The fundamental research on thermo-mechanical conditions provides an experimental basis for high-performance Mg-Al-Ca-Mn ***, there is a lack of systematical investigation for this series alloys on the hot-deformation kinetics and extrusion parameter optimization. Here, the flow behavior, constitutive model, dynamic recrystallization(DRX) kinetic model and processing map of a dilute rare-earth free Mg-1.3.l-0.4Ca-0.4Mn(AXM100, wt.%) alloy were studied under different hot-compressive conditions. In addition, the extrusion parameter optimization of this alloy was performed based on the hot-processing map. The results showed that the conventional Arrhenius-type strain-related constitutive model only worked well for the flow curves at high temperatures and low strain rates. In comparison, using the machine learning assisted model(support vector regression, SVR) could effectively improve the accuracy between the predicted and experimental values. The DRX kinetic model was established, and a typical necklace-shaped structure preferentially occurred at the original grain boundaries and the second phases. The DRX nucleation weakened the texture intensity, and the further growth caused the more scattered basal texture. The hot-processing maps at different strains were also measured and the optimal hot-processing range could be confirmed at the deformation temperatures of 600~7{3. K and the strain rates of 0.018~0.563.s^(-1). Based on the optimum hot-processing range, a suitable extrusion parameter was considered as 603.K and 0.1 mm/s and the as-extruded alloy in this parameter exhibited a good strength-ductility synergy(yield strength of ~ {3.2.1 MPa, ultimate strength of ~ {3.8.{3.MPa and elongation-to-failure of ~ {3..1%). Finally, the strengthening-plasticizing mechanisms and the relationships between the DRXed grain size, yield strength and extrusion parameters were analyzed.

关键词： Mg-Al-Ca-Mn alloy Constitutive model Dynamic recrystallization kinetic model Extrusion parameter optimization Strengthening-plasticizing mechanisms

Deep-sea coral evidence for dissolved mercury evolution in the deep North Pacifi c Ocean over the last 700 years

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Journal of Oceanology and Limnology 2021年第5期39卷 1622-1633页

作者： yang qu Kuidong XU Tao LI Maoyu WANG Huan ZHONG Tianyu chen State Key Laboratory for Mineral Deposits research School of EarthSciences and Engineering and Frontiers Science Center for Critical Earth Material CyclingNanjing UniversityNanjing 210023China Laboratory of Marine Organism Taxonomy and Phylogeny Institute ofOceanologyCenter for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China State Key Laboratory of Pollution Control and Resources Reuse School ofthe EnvironmentNanjing UniversityNanjing 210023China Environmental and Life Sciences Program(EnLS) Trent UniversityPeterboroughOntario K9L 0G2Canada center of Deep Sea research Institute of OceanologyCenter for OceanMega-ScienceChinese Academy of SciencesQingdao 266071China

The ocean is an important inventory of anthropogenic mercury(Hg),yet the history of anthropogenic Hg accumulation in the ocean remains largely ***-sea corals are an emerging archive of past ocean chemistry,which take in sinking or suspended particulate organic matter as their food *** organic matter would exchange Hg with the local seawater before being consumed by the deepsea *** such,the organics preserved in the coral skeleton may record the Hg evolution of the ambient seawater during the time of coral ***,we report the first data on Hg concentrations variability of a deep-sea proteinaceous coral in the oligotrophic North Pacific at the water depth of 12.9 m,in attempt to understand the transfer of anthropogenic Hg into the deep Pacific ocean over the last seven *** find that the Hg concentrations of different coral growth layers have remained relatively constant albeit with considerable short-term variability through *** overall stable Hg concentration of the last seven centuries recorded in our sample suggests that anthropogenic pollution is not yet a clearly resolvable component in the deep oligotrophic North Pacific waters,in agreement with rece nt estimation from modelling works and observational studies of modern seawater *** there is hardly an unambiguous way to separate anthropogenic Hg from the natural background based on recent seawater profiles,our historical data provide valuable information helping to understand the oceanic cycle of Hg through time.

关键词： deep-sea coral mercury deep water particulate organic matter anthropogenic perturbation

山东省临沂市楸树人工林立地类型划分与质量评价

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西北林学院学报 2024年第5期39卷 118-125页

作者：赵智佳单增罗布方洋关追追陈述王军辉何茜张鹏麻文俊中国林业科学研究院林业研究所国家林业局林木培育重点实验室林木遗传育种全国重点实验室北京100091 华南农业大学林学与风景园林学广东广州510642 临沂市森林湿地保护中心山东临沂276000 东北林业大学黑龙江哈尔滨150040 西藏自治区林木科学研究院西藏拉萨850000

使用典型抽样方法在山东临沂的蒙阴、沂水、兰陵等6个县区,选择造林技术和经营措施基本一致的14个样点布设63.楸树人工林临时标准地,调查标准地内立地因子、林分生长因子以及土壤因子,通过主成分分析、聚类分析法分析立地因子对人工林... 详细信息

使用典型抽样方法在山东临沂的蒙阴、沂水、兰陵等6个县区,选择造林技术和经营措施基本一致的14个样点布设63.楸树人工林临时标准地,调查标准地内立地因子、林分生长因子以及土壤因子,通过主成分分析、聚类分析法分析立地因子对人工林生长的影响,进而对楸树人工林进行立地类型划分与立地质量评价。结果表明:1)最合适的导向曲线为幂函数曲线,经χ~2.验证明所编制的立地指数表合格。2.在影响楸树人工林生长的立地因子中,重要性排序为:土壤质地>坡向>坡位>坡度>土层厚度>海拔,其中土壤质地、坡向、坡位是影响临沂市楸树人工林生长的主导因子。3.以土壤质地、坡向、坡位3.主导立地因子将山东省临沂市楸树人工林划分为13.立地类型,3.地位级。现有立地条件下,最适宜楸树人工林生长的立地特征为:分布在阳坡或半阴坡的下坡位,土壤质地为中壤土的地区,占总标准地数量的13.64%。整体上,临沂市楸树人工林的立地质量有待提高,建议Ⅰ、Ⅱ地位级种植中大径材楸树,Ⅲ地位级种植小径材楸树。

关键词：楸树立地类型立地质量临沂

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The relationship between the growth process of the ferromanganese crusts in the Pacific seamount and Cenozoic ocean evolvement

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Science China Earth Sciences 2009年第8期52卷 1091-1103页

作者： DING Xuan GAO LianFeng FANG NianQiao qu wenjun LIU Jian LI JiangShan School of Marine Science China University of GeosciencesBeijing 100083China College of Resources and Environments Hebei Polytechnic UniversityTangshan 063009China national Geologic Experiment and Test center Beijing 100037China Guangzhou Marine Geological Survey Guangzhou 510075China

Base on the Os isotope stratigraphy together with the empirical growth rate models using Co concentrations, the growth ages of the ferromanganese crusts MHD79 and MP3.10 distributed in the seamount of Pacific are confirmed. Through the contrast and research on the previous achievements including ODP Leg 144 and the crusts CD2.-2. N5E-06 and N1-15 of the seamount of the Central Pacific, the uniform five growth and growth hiatus periods of them are found, and closely related to the Cenozoic ocean evolvement process. In the Paleocene Carbon Isotope Maximum (PCIM), the rise of the global ocean productivity promoted the growth of the seamount crust; the first growth hiatus (I) of the ferromanganese crust finished. In the Paleocene-Eocene Thermal Maximum (PETM), though the vertical exchange of seawater was weakened, the strong terrestrial chemical weathering led to the input of a great amount of the terrigenous nutrients, which made the bioproductivity rise, so there were no crust hiatuses. during 52.50 Ma, the Early Eocene Optimum Climate (EECO), the two poles were warm, the latitudinal temperature gradient was small, the wind-driven sea circulation and upwelling activity were weak, the terrestrial weathering was also weakened, the open ocean bioproductivity decreased, and the ferromanganese crust had growth hiatus again (II). From early Middle Eocene-Late Eocene, Oligocene, it was a long-term gradually cooling process, the strengthening of the sea circulation and upwelling led to a rise of bioproductivity, and increase of the content of the hydrogenous element Fe, Mn and Co and the biogenous element Cu, Zn, so that was the most favorable stage for the growth of ferromanganese crust (growth periods III and IV) in the studied area. The hiatus III corresponded with the Eocene-Oligocene boundary, is inferred to relate with the global climate transformation, celestial body impact event in the Eocene-Oligocene transition. From the early to the middle Miocene, a large-scale gr

关键词： Pacific seamount ferromanganese crust growth period and growth hiatus period Cenozoic ocean evolvement

Re–Os molybdenite age of the Cu–Mo skarn ore deposit at Suoerkuduke in East Junggar, NW China and its geological significance

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Re–Os molybdenite age of the Cu–Mo skarn ore deposit at Su...

Performance of a plastic scintillation fiber dosimeter based on different photoelectric devices

中国科学院地质与地球物理研究所2.14年度（第14届）学术年会

作者： Bo Wan Wenjiao Xiao Chunming Han Brian F.Windley Lianchang Zhang wenjun qu andao {3. State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Xinjiang research center for Mineral Resources Xinjiang Institute of GeographyChinese Academy of Sciences Department of Geological Sciences Stockholm University Department of Geology University of Leicester Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of Sciences national research {2. of{3.

The Suoerkuduke Cu–Mo ore is a medium-sized skarn deposit in the East Junggar orogen of the southern Altaids, Xinjiang, Northwest China. We measured Re–Os isotopes of a molybdenite veinlet from the main ore body, of which eight yielded model ages ranging from 3.3.± 5 to 3.7 ± 5 Ma with a well-constrained187Re–187Os isochron age of 3.5 ± 7 Ma, a MSWD of 4.9 and a weighted average model age of 3.0 ± 4 Ma with a MSWD of 4.2. The187Re–187Os isochron age is consistent with the weighted mean model age, within error, and indicates that the time of Cu–Mo mineralization was at c. 3.0 Ma in the late *** new age is close to the youngest porphyry-related Cu–Mo metallogenic epoch(c. 3.1 Ma) in the East Junggar region, and is not, as previously suggested, in the Permian. Considering the implications of this new age, we propose that the Suoerkuduke deposit was part of a large-scale porphyry–skarn system, which formed by the interaction between far-traveled hydrothermal f{3.ids and the calcium-rich volcanic wall rocks.

关键词： Re-Os age Skarn Cu-Mo deposit East Junggar Porphyry-Skarn system Southern Altaids

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Nuclear Science and Techniques 2021年第11期32卷 25-31页

作者： Yue yang Cui-Ping yang Jie Xin Hai-Feng {2. Zhong-Xu Xing Wei-Wei {3. Liang Hu Xin-Jian {2. Ren-Sheng Wang State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China Renji Hospital Affiliated with the Shanghai Jiao Tong University School of MedicineShanghai 200127China Shanghai Ninth People’s Hospital Affiliated with the Shanghai Jiao Tong University School of MedicineShanghai 200127China Collaborative Innovation center of Radiological Medicine of Jiangsu Higher Education Institutions Suzhou 215123China

The photoelectric device of a scintillation dosimeter converts photons produced by radiation into an electrical *** features directly determine the overall performance of the *** a plastic scintillation fiber dosimeter(PSFD)with a current readout mode,systematic studies of the stability and light-dose response were performed for the photomultiplier tube(PMT),silicon photomultiplier(SiPM),avalanche photodiode(APD),and photodiode(PD).The temperature stability,long-term stability,repeatability,signal-to-noise ratio(SNR),and current dose response of the PSFD with the abovementioned photoelectric devices were studied using a pulsed LED light source and the Small Animal Radiation Therapy *** exponential relationship between the dark/ne current and temperature was obtained for all the devices.I is shown that the APD is the most sensitive device to temperature,with a current dependence on temperature reaching 6.5%C^(-1)at room temperature,whereas for the other devices this dependence is always2.when working intermittently for 3.1}h,whereas for the other devices,the changes are all3.ded to be better than that of the other devices in the *** particular,the SiPM,which has a compact size,low bias voltage,and antimagnetic interference,has great advantages for further applications.

关键词： Photoelectric device Plastic scintillation fiber dosimeter(PSFD) Current readout Dose response

HAND2.AS1,PRKAA2.and VLDLR predict the risk of peritoneal metastasis in gastric cancer of different Lauren types based on STEPP analysis

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BIOCELL 2022年第3期46卷 721-735页

作者： HUI qu RUICHUAN SHI BOWEN yang XI chen YUJIA SONG LINGZI HE YITING SUN YUJING yang ZHI LI XIUJUAN qu Department of Medical Oncology The First Hospital of China Medical UniversityShenyang110001China Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province The First Hospital of China Medical UniversityShenyang110001China Liaoning Province Clinical research center for Cancer Shenyang110001China Key Laboratory of Precision Diagnosis and Treatment of Gastrointestinal Tumors Ministry of EducationShenyang110001China

The peritoneum is the most common site of recurrence of gastric cancer(GC).Early occult peritoneal metastasis is difficult to detect by imaging *** the risk of peritoneal metastasis in patients with different Lauren subtypes is of great clinical *** performed a univariate Cox regression to identify those genes with prognostic value of overall survival(OS)and peritoneal-specified disease-free survival(psDFS)from the Gene Expression Omnibus *** candidate genes were screened by the Subpopulation Treatment Effect Pattern Plot(STEPP)*** score matching(PSM)analysis was used to reduce the interference of confounders on the *** on the optimal cut-off values determined by the STEPP method,we found overexpression of three genes(HAND{3.AS1,PRKAA{3.and VLDLR)was correlated with shorter 1-year psDFS among patients with diffuse-type than that of patients with intestinal-type GC,and it is highly *** Set Enrichment Analysis(GSEA)potentially suggested that the three genes promote the early occurrence of peritoneal metastasis in patients with diffuse-type GC through glucose metabolism-related *** three genes may be potential *** can be used to assess the risk of peritoneal metastases to guide treatment decisions and follow-up strategies.

关键词： Peritoneal metastasis Gastric cancer Lauren STEPP

Visible Light-Mediated Construction of Sulfonated Dibenzazepines

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Chinese Journal of Chemistry 2021年第8期39卷 2220-2226页

作者： Chuan-Hua qu Gui-Ting Song Jian-Hua Ou Dian-Yong Tang Zhi-gang Xu Zhong-Zhu chen College of Pharmacy National&Local Joint Engineering Research Center of Targeted and Innovative TherapeuticsChongqing Key Laboratory of Kinase Modulators as Innovative MedicineChongqing University of Arts and SciencesChongqing 402160China

A new method to access sulfonated dibenz[b,e]azepines via visible-light photoredox catalysis is *** ying inexpe nsive and commercially available sulfonyl chlorides to form the sulfonyl radicals enables the alkyne addi... 详细信息

关键词： Photocatalysis Sulfonated dibenzazepines Radical reactions Ugi reaction Annulation

Lipocalin-2.Mediated Insufficient Oligodendrocyte Progenitor Cell Remyelination for White Matter Injury After Subarachnoid Hemorrhage via SCL2.0}7 Receptor/Early Growth Response Protein 1 Signaling

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Neuroscience Bulletin 2022年第12期38卷 1457-1475页

作者： Qiang Li Xufang Ru yang yang Hengli Zhao Jie qu Weixiang {{3. Pengyu Pan Huaizhen Ruan Chaojun Li Yujie {{3. Hua Feng Department of Neurosurgery and State Key Laboratory of Trauma Burn and Combined InjurySouthwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China Department of Neurobiology College of Basic Medical SciencesThird Military Medical University(Army Medical University)Chongqing 400038China Model Animal research center Nanjing UniversityNanjing 210032China Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China Chongqing Clinical research center for Neurosurgery Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China

Insufficient remyelination due to impaired oligodendrocyte precursor cell(OPC)differentiation and maturation is strongly associated with irreversible white matter injury(WMI)and neurological *** analyzed whole transcriptome expression to elucidate the potential role and underlying mechanism of action of lipocalin-2.LCN2.in OPC differentiation and WMI and identified the receptor SCL2.0}7 and downstream transcription factor early growth response protein 1(EGR1)as the key signals contributing to LCN2.mediated insufficient OPC *** LCN-knockdown and OPC EGR1 conditional-knockout mice,we discovered enhanced OPC differentiation in developing and injured white matter(WM);consistent with this,the specific inactivation of LCN2.SCl2.0}7/EGR1 signaling promoted remyelination and neurological recovery in both atypical,acute WMI due to subarachnoid hemorrhage and typical,chronic WMI due to multiple *** potentially represents a novel strategy to enhance differentiation and remyelination in patients with white matter injury.

关键词： White matter injury Oligodendrocyte progenitor cell Remyelination Subarachnoid hemorrhage Multiple sclerosis Lipocalin-2 Early growth response protein 1