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Acta Metallurgica Sinica(English Letters) 2023年第3期36卷 417-425页

作者： xueru Fan Lei Xie Qiang li Chuntao Chang Hongxiang li School of Physics Science and Technology Xinjiang UniversityUrumqi 830046China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

This work was focused on enhancement in the plasticity of Fe_(25)Co_(25)Ni_(25)(Si_(0.3)B_(0.7))_(25) high entropy bulk metallic glass(HE-BMG)by adding minor Cu(0–1.2,in at.%).It is found that the appropriate addition of Cu can efficiently improve the plasticity of the present HE-BMG while the excessive addition of Cu will deteriorate again the plasticity,and especially,the plastic strain of the present HE-BMG is improved from 0.8%for the Cu-free alloy to 4.7%for the 0.3 at.%Cu-added alloy.The transmission electron microscopy observation shows that there are manyα-Fe(Co,Ni)clusters with sizes of less than 5 nm dispersed in the glassy matrix in the 0.3 and 0.6 at.%Cu-added alloys,which may account for the significant improvement in the plasticity of the two alloys,and further increase in Cu content more than 0.9 at.%leads to the precipitation ofα-Fe(Co,Ni)and Fe(Co,Ni)B compound grains with diameters of tens of nanometers,in which the plasticity of the present HE-BMGs has deteriorated rapidly.

关键词： High entropy alloys Bulk metallic glasses Glass forming ability Nano-crystallization Plasticity Microstructure

Homodispersed B-CN/P-CN S-scheme homojunction for enhanced visible-light-driven hydrogen evolution

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Green Energy & Environment 2022年第5期7卷 1119-1127页

作者： Dashui Yuan Zongyuan li xueru Chen Jing Ding Hui Wan Guofeng Guan State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjing210009China

Proper interface and band alignment always play essential roles in the separation of photoexcited charge of photocatalysts.In this work,we prepared a homodispersed S-scheme carbon nitride homojunction with local electron structure difference by a facile pre-doping and two-step calcination approach.Boron doping into heptazine created extra acceptor impurity,and phosphorus doping into heptazine created extra donor impurity,which eventually modulated the electronic structure of carbon nitride.As heptazines with different element doping were integrated into carbon nitride by recalcination,B-CN and P-CN formed a homodispersed homojunction and thus produced a rich interface.Meanwhile,caused by Fermi energy levels equilibrium,the band bending constructed an S-scheme homojunction,which stimulated photogenerated electrons to transfer from CB of B-CN to VB of P-CN.The homodispersed S-scheme homojunction structure led to efficient suppression of recombination of photoinduced charge and retained stronger redox charge.Consequently,the photocatalytic performance was dramatically boosted to 2620 μmol g^(-1) from 60 μmol g^(-1) of pure CN in 4-h hydrogen evolution from water.This novel method for electron structure engineering helped to provide a new strategy for designing homojunction photocatalysts with excellent photocatalytic performance.

关键词： dispersed scheme doping

Emission enhancement and color modulation of Tm(Ho)/Yb codoped Gd_(2)(MoO_(4))_(3) thin films via the use of multilayered structure

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Journal of Rare Earths 2021年第7期39卷 765-771,I0001页

作者： liang li Fei Xing xueru Zhang Haoyue Hao Yuxiao Wang School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China Department of Physics Harbin Institute of TechnologyHarbin 150001China

The multilayered structure thin films(Gd_(2)(MoO_(4))_(3):Ho(Tm)/Yb@Gd_(2)(MoO_(4))_(3):Yb) were prepared through sol-gel and spin-coating method,while the average thinness was nearly 140 nm.We investigated the up-conversion luminescence of Gd_(2)(MoO_(4))_(3):Ho(Tm)/Yb@Gd_(2)(MoO_(4))_(3):Yb thin films,The results show that the double-layer structured thin films are able to increase the emission intensity.The fluorescence enhancement factors of the luminescence from Gd_(2)(MoO_(4))_(3):Ho/Yb@Gd_(2)(MoO_(4))_(3):Yb thin films,located at540 and 662 nm,reach 7.5 and 4.3,respectively.And the enhancement factors of emissions located at450,475 and 650 nm(Gd_(2)(MoO_(4))_(3):Tm/Yb@Gd_(2)(MoO_(4))_(3):Yb) reach 9,2 and 2,respectively.The considerable enhancement is due to the suppression of surface quenching and energy harvesting via the Yb ions in the outer shell.In addition,the emission color of thin films can be modulated from yellow to blue via tuning the number of Gd_(2)(MoO_(4))_(3):Ho/Yb and Gd_(2)(MoO_(4))_(3):Tm/Yb layers,which provides a feasible strategy to tune the up-conversion emission color.

关键词： Emission enhancement Multilayered-layer structured thin films Emission color tuning Up-conversion materials Rare earths

苏州范氏义庄田亩考述(1049—1899)

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中国经济史研究 2023年第5期 170-179页

作者：李学如常熟理工学院马克思主义学院常熟215500

苏州范氏义庄是传统宗族义庄的源头和典范,社会影响广泛且深远。作为义庄的核心要素,范氏庄田规模庞大,倍受世人关注。历史上关于该庄的田地亩数,流传着不同的文本说法。本文梳理清光绪二十五年(1899)《范氏家乘》所载史料,稽核互证,并... 详细信息

苏州范氏义庄是传统宗族义庄的源头和典范,社会影响广泛且深远。作为义庄的核心要素,范氏庄田规模庞大,倍受世人关注。历史上关于该庄的田地亩数,流传着不同的文本说法。本文梳理清光绪二十五年(1899)《范氏家乘》所载史料,稽核互证,并结合方志、文集等文献,拾遗补缺,考察自宋皇祐元年(1049)范氏义庄创建到清光绪二十五年间义庄田产的损益变化,估算不同时期的庄田面积,解析庄田增益路径及减损原因,以探求范氏义庄田亩规模的真实样貌,加深对传统宗族义庄的认识。

关键词：范氏义庄光绪《范氏家乘》义庄田亩

Heparinized PGA host-guest hydrogel loaded with paracrine products from electrically stimulated adipose-derived mesenchymal stem cells for enhanced wound repair

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再生工程(英文)

再生工程(英文) 2023年第3期4卷 225-237页

作者： Mengyao li Junliang li xueru Xiong Yushi Wang Yong-Guang Jia Xuetao Shi Xiaoling Fu School of Materials Science and Engineering South China University of TechnologyGuangzhou 510641China School of Biomedical Sciences and Engineering South China University of TechnologyGuangzhou International CampusGuangzhou 511442China National Engineering Research Center for Tissue Restoration and Reconstruction and Innovation Center for Tissue Restoration and Reconstruction Guangzhou 510006China Key Laboratory of Biomedical Engineering of Guangdong Province South China University of TechnologyGuangzhou 510006China

The microenvironment of the wound bed is essential in the regulation of wound repair.In this regard,strategies that provide a repairing favorable microenvironment may effectively improve healing outcomes.Herein,we attempted to use electrical stimulation(ES)to boost the paracrine function of adipose-derived stem cells from rats(rASCs).By examining the concentrations of two important growth factors,VEGF and PDGF-AA,in the cell culture supernatant,we found that ES,especially 5𝜇A ES,stimulated rASCs to produce more paracrine factors(5𝜇A-PFs).Further studies showed that ES may modulate the paracrine properties of rASCs by upregulating the levels of TRPV2 and TRPV3,thereby inducing intracellular Ca^(2+) influx.To deliver the PFs to the wound to effectively improve the wound microenvironment,we prepared a heparinized PGA host-guest hydrogel(PGA-Hp hydrogel).Moreover,PGA-Hp hydrogel loaded with 5𝜇A-PFs effectively accelerated the repair process of the full-thickness wound model in rats.Our findings revealed the effects of ES on the paracrine properties of rASCs and highlighted the potential application of heparinized PGA host-guest hydrogels loaded with PFs derived from electrically stimulated rASCs in wound repair.

关键词： Wound repair Electrical stimulation Paracrine factors Heparinized PGA host-guest hydrogel

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千百年尺度祁连山地区干湿变化对暖期的响应

地理学报 2022年第5期77卷 1138-1152页

作者：周雪如李育兰州大学资源环境学院干旱区水循环与水资源研究中心兰州730000

全球升温导致区域干湿格局转变,千年尺度中全新世暖期和百年尺度中世纪暖期可以为探究现代的气候趋势提供历史相似型。通过湖相沉积、冰芯、孢粉、树轮等古气候记录和PMIP3/CMIP5计划的古气候模型模拟数据对比分析,结果表明,祁连山地区... 详细信息

全球升温导致区域干湿格局转变,千年尺度中全新世暖期和百年尺度中世纪暖期可以为探究现代的气候趋势提供历史相似型。通过湖相沉积、冰芯、孢粉、树轮等古气候记录和PMIP3/CMIP5计划的古气候模型模拟数据对比分析,结果表明,祁连山地区中全新世暖期(7.2—6.0 ka BP)东亚夏季风强盛,降水较多,气候温暖湿润;中世纪暖期(950—1250 AD)与小冰期表现为暖干—冷湿气候机制。现代观测数据显示,祁连山地区呈现暖湿化,但现代的气候机制与自然因子主导下暖期的响应机制差异较大,表明了人类活动对自然发展下气候环境的影响。因此,自然因素与人类活动共同作用是准确预测研究区未来干湿格局的基础。

关键词：祁连山中全新世暖期中世纪暖期现代暖期干湿变化

A New TDD Scheme and Interference-Aware Precoding for Device-to-Device Underlay Massive MIMO

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China Communications 2016年第S2期13卷 100-108页

作者： Xinxin liu Xueru Li Yunzhou li Ming Zhao Jing Wang State Key Laboratory on Microwave and Digital Communications Tsinghua National Laboratory for Information Science and Technology Tsinghua University Department of Electronic Engineering Tsinghua University

In device-to-device(D2D)underlay cellular networks with downlink spectrum sharing,massive MIMO seems promising as the large number of antennas at the base station(BS) can be utilized to suppress interference.However,the channel state information(CSI) from the BS to D2D receivers is required to obtain this advantage.In this paper,we first propose a novel time division duplex(TDD) scheme for D2D users to acquire this CSI,without additional pilot overhead.Moreover,we propose an interference-aware MMSE precoder utilizing the acquired CSI from the BS to not only cellular users but also D2D users to suppress the cellular-to-D2D interference.Simulation results show that our proposed TDD scheme and precoder can significantly improve the achievable sum spectral efficiency(SE) and D2D SE,compared to the classical MMSE precoder.Compared with the interferenceaware ZF precoder,whose performance severely degrades for large user numbers,our proposed interference-aware MMSE precoder can always guarantees a high and stable performance in terms of achievable SE.

关键词： device-to-device massive MIMO TDD scheme precoding

Transformation and mechanisms of climate wet/dry change on the northern Tibetan Plateau under global warming:A perspective from paleoclimatology

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Science China Earth Sciences 2024年第6期67卷 1932-1951页

作者： Yu li Zhansen ZHANG xueru ZHOU Minjun GAO Junjie DUAN Yaxin XUE Hao SHANG Shiyu liU Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China

The northern Tibetan Plateau is a climatically sensitive zone influenced by monsoon and westerly winds.In summer,water vapor transport can reach Qinghai Lake and the eastern section of the Qilian Mountains;in winter,westerly winds mainly control the climate.This article compares the wet/dry changes in the region during the mid-Holocene(MH)warm period,the medieval climate anomaly(MCA),the current warm period(CWP),and the future warm period from the perspective of paleoclimate.We found that the MH warm period was mainly affected by the orbit-controlled East Asian summer monsoon,and the region showed warm and humid climate characteristics.The MCA was mainly controlled by solar radiation,and there was a warm and dry phenomenon.The CWP and the future warm period are mainly controlled by the rise in temperature caused by the increase in greenhouse gases,and the climate is becoming more arid.The wet/dry patterns in the CWP and the future warm period in the next century on the northern Tibetan Plateau are similar to those in the MCA.Continued warming will lead to the expansion of the westerly belt and a gradually humid climate.The future wet/dry changes will be more similar to the MH warm period.

关键词： Northern Tibetan Plateau Wet/dry change Warm period similarity Driving mechanism Future assessment

Enabling ultranarrow blue emission linewidths in colloidal alloy quantum dots by decreasing the exciton fine structure splitting and exciton–phonon coupling

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Nano Research 2023年第1期16卷 1576-1585页

作者： Jinke Bai linfeng Wang Tingting Zhang Tianyi Hou Meilun Zhang Bing Xu Dongyu li Xiao Jin Qinghua li Yuxiao Wang xueru Zhang Yinglin Song Department of Physics Harbin Institute of TechnologyHarbin 150001China Guangdong Provincial Key Laboratory of Development and Education for Special Needs Children Lingnan Normal UniversityZhanjiang 524048China

The realization of colloidal alloy quantum dots(QDs)with narrow spectral linewidths requires minimization of the contributions of inhomogeneous and homogeneous broadening to the ensemble spectrum.Recently,there has been remarkable progress in eliminating the inhomogeneous contribution by controlling the size distribution of the QDs.However,considerable challenges remain in suppressing the homogeneous broadening,in terms of both intrinsic principles and rational synthetic routes.We find that ground-state exciton fine structure splitting and exciton-phonon coupling play a pivotal role in the homogeneous broadening mechanism.Here we demonstrate that the elimination of the lattice mismatch strain by using a coherent strain structure can decrease the light-heavy hole splitting,thus suppressing the asymmetric broadening of the emission on the high energy side.Besides,the improvement of the uniformity of the alloy by using a stepwise ion exchange strategy can weaken the exciton-longitudinal optical(LO)-phonon interactions,further minimizing the homogeneous broadening.As a result,the final alloy QD products exhibit a widely tunable blue emission wavelength(445-470 nm)with the narrowest ensemble photoluminescence full width at half maximum(FWHM)of 10.1-13.5 nm(or 58.4-75.3 meV).Our study provides a potential strategy for other semiconductor nanocrystals with ultranarrow spectral linewidths.

关键词： alloy quantum dots spectral linewidth light-heavy hole splitting exciton-phonon coupling homogeneous broadening

The essential role of N6-methyladenosine RNA methylation in complex eye diseases

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Genes & Diseases 2023年第2期10卷 505-520页

作者： Xiaohua li Binyun Ma Wenfang Zhang Zongming Song Xiaodan Zhang Mengyu liao Xue li xueru Zhao Mei Du Jinguo Yu Shikun He Hua Yan Henan Provincial People’s Hospital Henan Eye HospitalHenan Eye InstituteHenan Key Laboratory of Ophthalmology and Visual SciencePeople’s Hospital of Zhengzhou UniversityPeople’s Hospital of Henan UniversityZhengzhouHenan 450003China Department of Medicine/Hematology Keck School of Medicine of the University of Southern CaliforniaLos AngelesCA 90033USA Department of Ophthalmology Lanzhou University Second HospitalLanzhouGansu 730030China Department of Ophthalmology Tianjin Medical University General HospitalLaboratory of Molecular OphthalmologyTianjin Medical University. Department of Pharmacology and Tianjin Key Laboratory of Inflammation BiologySchool of Basic Medical SciencesTianjin Medical UniversityTianjin 300052China Department of Pathology and Ophthalmology USC Roski Eye InstituteKeck School of MedicineUniversity of Southern CaliforniaLos AngelesCA 90033USA

There are many complex eye diseases which are the leading causes of blindness,however,the pathogenesis of the complex eye diseases is not fully understood,especially the underlying molecular mechanisms of N6-methyladenosine(m6A)RNA methylation in the eye diseases have not been extensive clarified.Our review summarizes the latest advances in the studies of m6A modification in the pathogenesis of the complex eye diseases,including cornea disease,cataract,diabetic retinopathy,age-related macular degeneration,proliferative vitreoretinopathy,Graves’disease,uveal melanoma,retinoblastoma,and traumatic optic neuropathy.We further discuss the possibility of developing m6A modification signatures as biomarkers for the diagnosis of the eye diseases,as well as potential therapeutic approaches.

关键词： Degeneration Eye diseases Fibrosis Inflammation m6A RNA methylation Tumor