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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第11期10卷 1660-1669页

作者： Lei LI Nai-yun GAO Yang DENG Juan-juan YAO ke-jia ZHANG Hai-jun LI Di-di YIN Hua-se OU jian-wei GUO State key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China Department of Civil Engineering and Surveying University of Puerto Rico Mayaguez 00681 USA Faculty of Material Science and Chemistry Engineering China University of Geosciences Wuhan 430074 China

The degradation of Microcystin-LR (MC-LR) in water by hydrogen peroxide assisted ultraviolet (UV/H2O2) process was investigated in this paper. The UV/H2O2 process appeared to be effective in removal of the MC-LR. MC-LR decomposition was primarily ascribed to production of strong and nonselective oxidant-hydroxyl radicals within the system. The intensity of UV radiation, initial concentration of MC-LR, MC-LR purity, dosages of H2O2, the initial solution pH, and anions present in water, to some extent, influenced the degradation rate of MC-LR. A modified pseudo-first-order kinetic model was developed to predict the removal efficiency under different experimental conditions.

关键词： Microcystin-LR (MC-LR) Hydrogen peroxide assisted ultraviolet (UV/H2O2) process Hydroxyl radical Reaction kinetics Photochemical degradation

Frequency response range of terahertz pulse coherent detection based on THz-induced time-resolved luminescence quenching

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Chinese Physics B 2018年第6期27卷 127-131页

作者： Man Zhang Zhen-Gang Yang Jin-Song Liu ke-jia Wang jiao-Li Gong Sheng-Lie Wang School of Optical and Electronic Information Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan 430074 China

It has been proposed previously that the coherent detection of a terahertz（THz） pulse can be achieved based on the time-resolved luminescence quenching. In this paper, we investigate the frequency response range of this novel detection technology by simulating the motion of carriers in gallium arsenide（GaAs） by the ensemble Monte Carlo method. At room temperature, for a direct-current（DC） voltage of 20 kV/cm applied to the semiconductor（GaAs） and sampling time o140 fs, the luminescence quenching phenomena induced by terahertz pulses with different center frequencies are studied The results show that the quenching efficiency is independent of the THz frequency when the frequency is in a range o0.1 THz–4 THz. However, when the frequency exceeds 4 THz, the efficiency decreases with the increase of frequency Therefore, the frequency response range is 0.1 THz–4 THz. Moreover, when the sampling time is changed to 100 fs the frequency response range is extended to be approximately 0.1 THz–5.6 THz. This study of the frequency-dependen characteristics of the luminescence response to the THz pulse can provide a theoretical basis for the exploration of THz detection technology.

关键词： frequency response range terahertz-pulse coherent detection time-resolved luminescence quenching ensemble Monte Carlo method

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严重烧伤后骨骼肌消耗的机制与治疗前景思考

中华烧伤杂志 2009年第4期25卷 243-245页

作者：柴家科解放军总医院第一附属医院全军烧伤研究所北京100048

Most of the major advances in burn treatment were made within the last five decades. However, hypermetabolic response after severe burn remains a problem in the treatment of patients with massive burn. As skeletal muscle accounts for over 50% of body cell dry weight, its catabolism exerts profound effect on body metabolism as a whole. Main mechanisms underlying skeletal muscle wasting induced by severe burn include activation of ubiquitin-proteasome pathway, bringing about breakdown of muscle protein, and myonuclear apoptosis. Therapeutic strategies for skeletal muscle wasting after burn mainly include maintenance of room temperature at （31.5 ＋0.7） ℃ , early active and passive exercise of skeletal muscles, administration of β adrenergic receptor blocker such as Propranolol, recombinant growth hormone, androgen, and insulin, which has lately been proven to possess the effect of suppressing myonuclear apoptosis after burn. Combination of multiple therapeutic strategies is beneficial in reducing complications of burn patients, particularly wide ranged skeletal muscle atrophy, to achieve a better clinical outcome.

关键词：烧伤肌蛋白质类细胞凋亡药物疗法治疗

Solution-grown aligned crystals of diketopyrrolopyrroles(DPP)-based small molecules:Rough surfaces and relatively low charge mobility

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Chinese Chemical Letters 2016年第4期27卷 523-526页

作者： Zhuo-Ting Huang Cong-Cheng Fan Guo-Biao Xue jia-ke Wu Shuang Liu Huan-Bin Li Hong-Zheng Chen Han-Ying Li MOE key Laboratory of Macromolecular Synthesis and Functionalization State Key Laboratory of Silicon Materials Department of Polymer Science and Engineering Zhejiang University

Field-effect transistors（FETs） of three diketopyrrolopyrroles（DPP）-based small molecules, 3,6-bis（5-phenylthiophene-2-yl）-2,5-bis（2-ethylhexyl）pyrrolopyrrole-1,4-dione（PDPPP）, 3,6-bis（5-（4-fluorophenyl）thiophene-2-yl）-2,5-bis（2-ethylhexyl）pyrrolo pyrrole-1,4-dione（FPDPPPF） and 3,6-bis（5-（4-n-butylphenyl）thiophene-2-yl）-2,5-bis（2-ethylhexyl）pyrrolo pyrrole-1,4-dione（Bu PDPPPBu）, have been studied in this work. Well aligned crystals of the three molecules were grown from para-xylene by droplet-pinned crystallization method. FETs based on these aligned crystals exhibit a hole mobility up to0.19 cm^2 V 1s 1and electron mobility up to 0.008 cm^2 V 1s 1. The achieved hole mobility is of the same order of magnitude as reported highest hole mobility for DPP-based small molecules, but it is much lower than that of the high-performance DPP-based polymers. The relative low mobility is mainly attributed to the rough crystal surfaces with steps and, thus, non-smooth charge transport channels at the interfaces between the crystals and the dielectrics. This work has implications for understanding the low charge mobility of DPP-based small molecules.

关键词： Diketopyrrolopyrrole Crystals Solution processing Organic field-effect transistors Morphology

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远程监督实体关系抽取研究

情报科学 2021年第10期39卷 165-169,193页

作者：柯佳武汉大学信息管理学院湖北武汉430072

【目的/意义】实体关系抽取是构建领域本体、知识图谱、开发问答系统的基础工作。远程监督方法将大规模非结构化文本与已有的知识库实体对齐,自动标注训练样本,解决了有监督机器学习方法人工标注训练语料耗时费力的问题,但也带来了数据... 详细信息

【目的/意义】实体关系抽取是构建领域本体、知识图谱、开发问答系统的基础工作。远程监督方法将大规模非结构化文本与已有的知识库实体对齐,自动标注训练样本,解决了有监督机器学习方法人工标注训练语料耗时费力的问题,但也带来了数据噪声。【方法/过程】本文详细梳理了近些年远程监督结合深度学习技术,降低训练样本噪声,提升实体关系抽取性能的方法。【结果/结论】卷积神经网络能更好的捕获句子局部、关键特征、长短时记忆网络能更好的处理句子实体对远距离依赖关系,模型自动抽取句子词法、句法特征,注意力机制给予句子关键上下文、单词更大的权重,在神经网络模型中融入先验知识能丰富句子实体对的语义信息,显著提升关系抽取性能。【创新/局限】下一步的研究应考虑实体对重叠关系、实体对长尾语义关系的处理方法,更加全面的解决实体对关系噪声问题。

关键词：远程监督关系抽取神经网络注意力机制实体对齐

Teaching evaluation on a WebGIS course based on dynamic self-adaptive teaching–learning-based optimization

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Journal of Central South University 2019年第3期26卷 640-653页

作者： HOU Jing-wei jia ke-li jiaO Xue-jun School of Resources and Environment Ningxia University Ningxia (China-Arab) key Laboratory of Resource Assessment and Environment Regulation in Arid Region Institute of Surveying Mapping and Geographic Information of Henan

Teaching evaluation on a WebGIS course is a multi-objective nonlinear high-dimensional NP-hard problem. The index system for the teaching evaluation of a WebGIS course, including teacher- and student-oriented sub-systems, is first established and used for questionnaires from 2013 to 2017. The multi-objective nonlinear high-dimensional evaluation model is constructed and then solved via dynamic self-adaptive teaching–learning-based optimization (DSATLBO). DSATLBO is based on teaching–learning-based optimization with five improvements: dynamic nonlinear self-adaptive teaching factor, extracurricular tutorship factor, dynamic self-adaptive learning factor, multi-way learning factor, and non-dominated sorting factor. WebGIS teaching performance is fully evaluated based on questionnaires and DSATLBO. Optimal weights and weighted scores from DSATLBO are compared with those from the non-dominated sorting genetic algorithm-II using the Pareto front, coverage to two sets, and spacing of the non-dominated solution sets to validate the performance of DSATLBO. The results show that DSATLBO can be uniformly distributed along the Pareto front. Therefore, DSATLBO can efficiently and feasibly solve the multi-objective nonlinear high-dimensional teaching evaluation model of a WebGIS course. The proposed teaching evaluation method can help reflecting the quality of all aspects of classroom teaching and guide the professional development of students.

关键词： teaching evaluation multi-objective WebGIS DSATLBO optimization

FRB 171019:an event of binary neutron star merger?

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Research in Astronomy and Astrophysics 2020年第4期20卷 107-114页

作者： Jin-Chen jiang Wei-Yang Wang Rui Luo Shuang Du Xuelei Chen ke-jia Lee Ren-Xin Xu State key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China key Laboratory of Computational Astrophysics National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China CSIRO Astronomy and Space Science ATNFBox 76 EppingNSW 1710Australia Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

The fast radio burst,FRB 171019,was relatively bright when discovered first by ASKAP but was identified as a repeater with three faint bursts detected later by GBT and *** observations lead to the discussion of whether the first bright burst shares the same mechanism with the following repeating bursts.A model of binary neutron star merger is proposed for FRB 171019,in which the first bright burst occurred during the merger event,while the subsequent repeating bursts are starquake-induced,and generally fainter,as the energy release rate for the starquakes can hardly exceed that of the catastrophic merger *** scenario is consistent with the observation that no later burst detected is as bright as the first one.

关键词： pulsars:general stars:neutron dense matter gravitational waves

华北地区1900-1970年5级以上地震发震位置与震源机制研究

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地球物理学报 2016年第11期59卷 4089-4099页

作者：高彬贾科周仕勇北京大学地球与空间科学学院理论与应用地球物理研究所北京100871

本文通过整理世界地震台网1900—1970年世界台站震相报告,对该时期发生在我国华北地区震级5级以上强震的震源位置及震源机制(断层面解)进行了测量.具体开展了以下三点工作:(1)使用1900—1970年之间Shide Circulars(BAASSC,1900—1912),... 详细信息

本文通过整理世界地震台网1900—1970年世界台站震相报告,对该时期发生在我国华北地区震级5级以上强震的震源位置及震源机制(断层面解)进行了测量.具体开展了以下三点工作:(1)使用1900—1970年之间Shide Circulars(BAASSC,1900—1912),《国际地震资料汇编》(ISS)和EHB Bulletin的震相到时,对该时间范围内的22个地震事件重新定位,得到了21个地震事件的可靠结果;(2)使用1933年至1970年之间ISS的P波初动,对该时间范围内的15个地震事件求解震源机制解,得到了其中12个地震事件的震源机制解的可靠结果,从而丰富了华北地区基于全球地震台网观测的1900—1970年历史强震目录震源机制资料;(3)基于华北地区地震地质及区域构造应力场研究结果,推断了华北地区M≥5.0的部分缺乏地震资料观测的历史地震断层面参数,并对这种方法推断的断层面参数的可靠性进行了讨论.

关键词：华北地区历史地震地震定位震源机制解

Effects of nanofibers on mesenchymal stem cells:environmental factors affecting cell adhesion and osteogenic differentiation and their mechanisms

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2020年第11期21卷 871-884页

作者： Dan YU Jin WANG ke-jia QIAN Jing YU Hui-yong ZHU Department of Oral and Maxillofacial Surgery the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Stomatology Zhejiang University School of MedicineHangzhou 310058China

Nanofibers can mimic natural tissue structure by creating a more suitable environment for cells to grow,prompting a wide application of nanofiber *** this review,we include relevant studies and characterize the effect of nanofibers on mesenchymal stem cells,as well as factors that affect cell adhesion and osteogenic *** hypothesize that the process of bone regeneration in vitro is similar to bone formation and healing in vivo,and the closer nanofibers or nanofibrous scaffolds are to natural bone tissue,the better the bone regeneration process will *** general,cells cultured on nanofibers have a similar gene expression pattern and osteogenic behavior as cells induced by osteogenic supplements in *** involved in cell adhesion(focal adhesion kinase(FAK)),cytoskeletal organization,and osteogenic pathways(transforming growth factor-β(TGF-β)/bone morphogenic protein(BMP),mitogen-activated protein kinase(MAPK),and Wnt)are upregulated *** adhesion and osteogenesis may be influenced by several *** possess certain physical properties including favorable hydrophilicity,porosity,and swelling properties that promote cell adhesion and ***,nanofiber stiffness plays a vital role in cell fate,as cell recruitment for osteogenesis tends to be better on stiffer scaffolds,with associated signaling pathways of integrin and Yes-associated protein(YAP)/transcriptional co-activator with PDZ-binding motif(TAZ).Also,hierarchically aligned nanofibers,as well as their combination with functional additives(growth factors,HA particles,etc.),contribute to osteogenesis and bone *** summary,previous studies have indicated that upon sensing the stiffness of the nanofibrous environment as well as its other characteristics,stem cells change their shape and tension accordingly,regulating downstream pathways followed by adhesion to nanofibers to contribute to ***,additional experiments are needed to id

关键词： Nanofiber Stem cell Mimicking natural tissue Morphology Signaling pathway

Excited-State Double Proton Transfer of 1,8-Dihydroxy-2-Naphthaldehyde:a MS-CASPT2//CASSCF Study

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Chinese Journal of Chemical Physics 2022年第3期35卷 422-430,I0001页

作者： Bin-Bin Xie ke-Xin Wang Pei-ke jia Xiang-Yang Liu Ganglong Cui Hangzhou Institute of Advanced Studies Zhejiang Normal UniversityHangzhou 311231China College of Chemistry and Material Science Sichuan Normal UniversityChengdu 610068China key Laboratory of Theoretical and Computational Photochemistry Ministry of Education College of ChemistryBeijing Normal UniversityBeijing 100875China

Excited-state double proton transfer(ESDPT)is a controversial issue which has long been plagued with theoretical and experimental ***,we took 1,8-dihydroxy-2-naphthaldehyde(DHNA)as a prototype and used combined complete active space selfconsistent field(CASSCF)and multi-state complete active-space second-order perturbation(MS-CASPT2)methods to investigate ESDPT and excited-state deactivation pathways of *** different tautomer minima of S1-ENOL,S1-keTO-1,and S1-keTO-2 and two crucial conical intersections of S1 S0-keTO-1 and S1 S0-keTO-2 in and between the S0 and S1 states were obtained.S1-keTO-1 and S1-keTO-2 should take responsibility for experimentally observing dual-emission *** addition,two-dimensional potential energy surfaces(2 D-PESs)and linear interpolated internal coordinate paths connecting relevant structures were calculated at the MS-CASPT2//CASSCF level and confirmed a stepwise ESDPT ***,the first proton transfer from S1-ENOL to S1-keTO-1 is barrierless,whereas the second one from S1-keTO-1 to S1-keTO-2 demands a barrier of ca.6.0 kcal/*** linear interpolated internal coordinate path connecting S1-keTO-1(S1-keTO-2)and S_(1) S0-keTO-1(S1 S0-keTO-2)is uphill with a barrier of ca.12.0 kcal/mol,which will trap DHNA in the S_(1) state while therefore enabling dual-emission *** the other hand,the S1/S0 conical intersections would also prompt the S_(1) system to decay to the S_(0) state,which could be to certain extent suppressed by locking the rotation of the C5-C8-C9-O10 dihedral *** mechanistic insights are not only helpful for understanding ESDPT but also useful for designing novel molecular materials with excellent photoluminescent performances.

关键词： Excited-state double proton transfer 1,8-Dihydroxy-2-naphthaldehyde MS-CASPT2//CASSCF