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Acta Metallurgica Sinica(English Letters) 2014年第3期27卷 422-429页

作者： Changsheng li Biao Ma tao li tao Zhu State Key Laboratory of Rolling and Automation Northeastern University

The 1,000 MPa ultra-high strength hot-rolled plate steel with low-carbon bainitic microstructure was developed in the laboratory for coal mine refuge chamber. The static recrystallization behavior, microstructure evolution, and mechanical properties of this hot-rolled plate steel were investigated by the hot compression, continuous cooling trans- formation, and tensile deformation test. The results show that the developed steel has excellent mechanical properties at both room and elevated temperature, and its microstructure mainly consists of lath bainite, granular bainite, and ferrite after thermal-mechanical control process （TMCP）. The ultra-high strength plate steel is obtained by the TMCP process in hot rolling, strengthened by bainitic transformation, microstructure refinement, and precipitation of alloying elements such as Nb, Ti, Mo, and Cu. The experimental steel has relatively low welding crack sensitivity index and high atmospheric corrosion resistance index. Therefore, the developed steel has a good balance of strength and ductility both at room and elevated temperature, weldability and corrosion resistance, and it can suffice for the basic demands for materials in the manufacture of coal mine refuge chamber.

关键词： Ultra-high strength steel Low-carbon bainite Coal mine refuge chamber Microstructure Mechanical property

High-precision nuclear magnetic resonance probe suitable for in situ studies of high-temperature metallic melts

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Chinese Physics B 2022年第4期31卷 48-55页

作者： Ao li Wei Xu Xiao Chen Bing-Nan Yao Jun-tao Huo Jun-Qiang Wang run-Wei li CAS Key Laboratory of Magnetic Materials and Devices and Zhejiang Province Key Laboratory of Magnetic Materials and Application TechnologyNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

High-temperature nuclear magnetic resonance(NMR)has proven to be very useful for detecting the temperatureinduced structural evolution and dynamics in ***,the sensitivity and precision of high-temperature NMR probes are *** we report a sensitive and stable high-temperature NMR probe based on laser-heating,suitable for in situ studies of metallic melts,which can work stably at the temperature of up to 2000 *** our design,a well-designed optical path and the use of a water-cooled copper radio-frequency(RF)coil significantly optimize the signal-to-noise ratio(S/NR)at high ***,a precise temperature controlling system with an error of less than±1 K has been *** temperature calibration,the temperature measurement error is controlled within±2 *** a performance testing,^(27)Al NMR spectra are measured in Zr-based metallic glass-forming liquid in *** show that the S/NR reaches 45 within 90 s even when the sample's temperature is up to 1500 K and that the isothermal signal drift is better than0.001 ppm per *** high-temperature NMR probe can be used to clarify some highly debated issues about metallic liquids,such as glass transition and liquid-liquid transition.

关键词： high-temperature NMR probe laser beams temperature measurement metallic melts

The engagement of histone lysine methyltransferases with nucleosomes: structural basis, regulatory mechanisms, and therapeutic implications

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Protein & Cell 2023年第3期14卷 165-179页

作者： Yanjing li Kexue Gei Tingting li run Cai Yong Chen State Key Laboratory of Molecular Biology National Center for Protein Science ShanghaiShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academyof Sciences320 Yue Yang RoadShanghai 200031China State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai Collaborative Innovation Center for Biomanufacturing(SCICB)Meilong Road 130Shanghai 200237China

Histone lysine methyltransferases(HKMTs)deposit methyl groups onto lysine residues on histones and play important roles in regulating chromatin structure and gene *** structures and functions of HKMTs have been extensively investigated in recent decades,significantly advancing our understanding of the dynamic regulation of histone ***,we review the recent progress in structural studies of representative HKMTs in complex with nucleosomes(H3K4,H3K27,H3K36,H3K79,and H4K20 methyltransferases),with emphasis on the molecular mechanisms of nucleosome recognition and trans-histone crosstalk by these *** structural studies inform HKMTs'roles in tumorigenesis and provide the foundations for developing new therapeutic approachestargetingHKMTs incancers.

关键词： nucleosome cryo-EM structures histone methyltransferases epigenetics histone methylation tumorigenesis

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我国未来学习中心建设现状与路径探索

大学图书情报学刊 2025年第1期43卷 37-42,65页

作者：李小涛解玲南京航空航天大学图书馆 210016 南京航空航天大学经济与管理学院 210016

建设未来学习中心,是推进高等教育数字化转型和高校图书馆服务升级的有效途径。调研未来学习中心建设现状及存在问题,可为我国高等院校未来学习中心建设实践提供参考借鉴。文章运用文献调研和网络调查的方法,从顶层设计、建设理念、空... 详细信息

建设未来学习中心,是推进高等教育数字化转型和高校图书馆服务升级的有效途径。调研未来学习中心建设现状及存在问题,可为我国高等院校未来学习中心建设实践提供参考借鉴。文章运用文献调研和网络调查的方法,从顶层设计、建设理念、空间建设、资源建设、服务创新5个维度对全国高等院校未来学习中心建设实践进行调查,并对调查结果进行归类、统计和分析。研究发现,我国未来学习中心建设正处于起步探索期,在具体实践中存在着顶层设计不足、技术应用与教学模式融合不深等问题。针对这些问题,文章提出了相应的建设路径。

关键词：未来学习中心高校图书馆建设现状网络调研

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Recovery of rare earths from ion-absorbed rare earths ore with MgSO_4-ascorbic acid compound leaching agent

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Journal of Rare Earths 2018年第5期36卷 521-527页

作者： Fuguo Lai li Huang Guohua Gao run Yang Yanfei Xiao School of Metallurgical and Chemical Engineering Jiangxi University of science and Technology Ganzhou 341000 China Institute of Engineering ＆ Research Jiangxi University of Science and Technology Ganzhou 341000 China

The magnesium sulfate leaching technology for the ion-absorbed rare earths ore can solve the ammonia pollution problem existing in ammonium sulfate leaching process. However, the leaching capacity of magnesium sulfate is slightly weaker than that of ammonium sulfate, resulting in a bigger consumption of magnesium sulfate. In this paper, the MgSO4-ascorbic acid compound leaching agent had been demonstrated to deal with the ion-absorbed rare earths ore. The ascorbic acid could form a stable coordination with rare earth ions, so that it can strengthen the leaching of ion-exchangeable ***, ascorbic acid has a strong reductive property, it can leach the colloidal sediment phase rare earth as well. The present study investigates the effect of the initial pH and the composition of leaching agent on the rare earth leaching. It is determined that the rare earth leaching efficiency is 107.5% under the condition of pH 2.00,0.15 mol/L magnesium sulfate and 1.0 g/L ascorbic acid in leaching agent. In this case, the content of the ion-exchangeable phase and colloidal sediment phase rare earth in the leaching residues are both only 0.02‰. The leaching efficiency of colloid sediment phase rare earth can be 85.7%,so that the Ce partition in the leaching liquor increases to be 5.77%. The magnesium-ascorbic acid compound leaching agent is proposed to be a promising choice to deal with the ion-absorbed rare earths ore, which can realize the efficient leaching, low consumption of MgSO4 and environmentally friendly leaching.

关键词： Rare earth Leaching MgSO4 Ascorbic acid Ion-absorbed rare earths ore

Ramet Population Structure of Fargesia nitida （Mitford） Keng f. et Yi in Different Successional Stands of the Subalpine Coniferous Forest in Wolong Nature Reserve

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Journal of Integrative Plant Biology 2006年第10期48卷 1147-1153页

作者： Xiao-Hong Yu Jian-Ping tao Yuan li Yong-Jian Wang Yi Xi Wei-Yin Zhang run-Guo Zang Key Laboratory of Eco-environments of Three Gorges Reservoir Region Ministry of Education School of Life Sciences Southwest University Chongqing 400715 China Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing 100091 China

Forest structure and succession in Wolong Nature Reserve is influenced by the understory dwarf bamboo population. However, less is known about how the forest succession affects the dwarf bamboo population. To examine the bamboo ramet population growth of Fargesla nitida （Mltford） Keng f. et Yi and to determine how ramet population structure varies along the succession of coniferous forest, we sampled ramet populations of F. nitida from the following three successional stages：（i） a deciduous broad-leaved （BL） stand; （ii） a mixed broad-leaved coniferous （MI） stand; and （ill） a coniferous （CF） stand. We investigated the population structure, biomass allocation, and morphological characteristics of the bamboo ramet among the three stand types. Clonal ramets, constituting the bamboo population, tended to become short and small with succession. The ramet changed towards having a greater mass investment in leaves, branches and underground roots and rhizomes rather than in the culm. With respect to leaf traits, individual leaf mass and area in the BL stand were markedly bigger than those In both the MI and CF stands, except for no significant difference in specific leaf area. The age distribution showed that the bamboo population approached an older age with succession. The results demonstrate that the ramet population structure of F. nitida is unstable and its growth performance is inhibited by succession.

关键词： coniferous forest Fargesia nitida ramet population structure succession Wolong Nature Reserve

Capsizing Probability of Dead Ship Stability in Beam Wind and Wave for Damaged Ship

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China Ocean Engineering 2019年第2期33卷 245-251页

作者： HU li-fen ZHANG Ke-zheng li Xiao-ying CHANG run-xin School of Transporation Ludong University

The International Maritime Organization has developed the second-generation intact stability criteria. Thus, damage stability criteria can be established in the future. In order to identity the capsizing probability of damaged ship under dead ship condition, this paper investigates two methods that can be used to research the capsizing probability in time domain, which mainly focus on the nonlinear righting lever GZ curve solution. One method subjects the influence of damaged tanks on the hull shape down to the wind and wave, and the other method is consistent with the real-time calculation of the GZ curve. On the basis of one degree of freedom rolling equation, the solution is Monte Carlo method, and a damaged fishery bureau vessel is taken as a sample ship. In addition, the results of the time-domain capsizing probability under different loading conditions are compared and analyzed. The relation of GM and heeling angle with the capsizing probability is investigated, and its possible reason is analyzed. On the basis of combining the time-domain flooding process with the capsizing probability calculation, this research aims to lay the foundation for the study of capsizing probability in time domain under dead ship condition, as well as provide technical support for capsizing mechanism of dead ship stability and damage stability criteria establishment in waves.

关键词： damage stability criteria dead ship stability capsizing probability flooding process time domain

Skarn mineralogy and its geological significance for the Tayuan (Cu-Mo)-Pb-Zn deposit, northern Daxinganling metallogenic belt

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Acta Geochimica 2017年第1期36卷 89-101页

作者： Chao li tao Ren Jian-Guo Huang run-Sheng Han He-Jun Yin Hong-Yang Zhou Zhi-Hong Feng Kunming University of Science and Technology Kunming 650093 China Yunnan Chihong Zinc & Germanium limited liability Company Kunming 650000 China Daxinganling Yunye Mining Development limited liability Company Jiagedaqi 165021 China

The Tayuan(Cu-Mo)-Pb-Zn deposit is located in the northern part of Daxinganling,NE *** ore body occurs in the skarn *** skarn minerals mainly include garnet,pyroxene,epidote and *** microprobe analysis shows that the end member of garnet is mainly andradite(Ad_(62-97)Gr_(11-45),the pyroxene is mainly diopside,and epidote is mainly *** characteristics indicate that the Tayuan polymetallic skarn deposit is mainly calcareous *** the content zonation can be observed in *** one garnet crystal,content is shifty from the core to the *** general,the iron content in the core is higher than in the *** content in the garnet shows that the garnet in the Tayuan deposit formed from weak oxidation in alkaline environment with the oxygen fugacity increasing,suggesting that the hydrothermal fluid evolved from an acidic to a slight alkaline *** the Tayuan polymetallic deposit,the ratio of Mn/Fe in pyroxene is about 1.3,and of Mg/Fe,it is about *** components of garnet in the Tayuan deposit plot in the field of the typical skarn Zn,Cu,Mo deposits in the world.

关键词： Skarn minerals (Cu Mo) Pb Zn deposit Physical chemical condition Tayuan

Projection-based High-dimensional Sign Test

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Acta Mathematica Sinica,English Series 2022年第4期38卷 683-708页

作者： Hui CHEN Chang liang ZOU run Ze li School of Statistics and Data Science Nankai UniversityTianjin 300071P.R.China Department of Statistics and Methodology Center Pennsylvania State University201 Old MainUniversity ParkPA 16802USA

This article is concerned with the high-dimensional location testing *** highdimensional settings,traditional multivariate-sign-based tests perform poorly or become infeasible since their Type I error rates are far away from nominal *** modifications have been proposed to address this challenging issue and shown to perform ***,most of modified sign-based tests abandon all the correlation information,and this results in power loss in certain *** propose a projection weighted sign test to utilize the correlation *** mild conditions,we derive the optimal direction and weights with which the proposed projection test possesses asymptotically and locally best power under *** from using the sample-splitting idea for estimating the optimal direction,the proposed test is able to retain type-I error rates pretty well with asymptotic distributions,while it can be also highly competitive in terms of *** advantage relative to existing methods is demonstrated in numerical simulations and a real data example.

关键词： High dimensional location test problem locally optimal test nonparametric test sample-splitting spatial sign test

Analysis of the value and safety of thyroid-stimulating hormone in the clinical efficacy of patients with thyroid cancer

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World Journal of Clinical Cases 2023年第5期11卷 1058-1067页

作者： Jian-Jing liang Wen-Jing Feng Ru li run-tao Xu Yu-Long liang Department of Medicine Hebei UniversityBaoding 071000Hebei ProvinceChina Department of General Surgery the Third Hospital of Hebei Medical UniversityShijiazhuang 050051Hebei ProvinceChina Department of Cardiology First Hospital of Xinji CityXinji 052300Hebei ProvinceChina

BACKGROUND Thyroid cancer(TC)is a common malignant tumor in the endocrine *** recent years,the incidence and recurrence rates of TC have been raising due to increasing work pressure and irregular ***-stimulating hormone(TSH)is a specific parameter for thyroid function *** study aims to explore the clinical value of TSH in regulating the progression of TC,so as to find a breakthrough for the early diagnosis and treatment of *** To explore the value and safety of TSH in the clinical efficacy of patients with *** 75 patients with TC admitted to the Department of Thyroid and Breast Surgery of our hospital from September 2019 to September 2021 were selected as the observation group,and 50 healthy subjects were selected as the control group during the same *** control group was treated with conventional thyroid replacement therapy,and the observation group was treated with TSH suppression *** soluble interleukin(IL)-2 receptor(sIL-2R),IL-17,IL-35levels,free triiodothyronine(FT3),free tetraiodothyronine(FT4),CD3+,CD4+,CD8+,CD44V6,and tumor supplied group of factor(TSGF)levels were observed in the two *** occurrence of adverse reactions was compared between the two *** After treatment with different therapies,the levels of FT3,FT4,CD3+,and CD4+in the observation group and the control group were higher than those before treatment,while the levels of CD8+,CD44V6,and TSGF were lower than those before treatment,and the differences were statistically significant(P<0.05).More importantly,the levels of sIL-2R and IL-17 in the observation group were lower than those in the control group after 4 wk of treatment,while the levels of IL-35 were higher than those in the control group,and the differences were statistically significant(P<0.05).The levels of FT3,FT4,CD3+,and CD4+in the observation group were higher than those in the control group,and the levels of CD8+,CD44V6,and TSGF were lower than those in the co

关键词： Thyroid-stimulating hormone Thyroid cancer Clinical efficacy Safety profile