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量子点制备与表面修饰

化学通报 2013年第9期76卷 822-827页

作者：刘富华麻鹏聂立波湖南工业大学绿色包装与生物纳米技术应用重点实验室株洲412007

量子点具有荧光强度高、光化学稳定性高、可反复多次激发等优点,在生物医学以及新能源等方面有广阔的应用前景。本文介绍了量子点的制备与表面修饰,制备方法主要包括沉淀法、溶胶-凝胶法、微乳液法、水热法等,表面修饰方法主要有双功能... 详细信息

量子点具有荧光强度高、光化学稳定性高、可反复多次激发等优点,在生物医学以及新能源等方面有广阔的应用前景。本文介绍了量子点的制备与表面修饰,制备方法主要包括沉淀法、溶胶-凝胶法、微乳液法、水热法等,表面修饰方法主要有双功能团配体交换、硅烷化、聚合物包埋等。

关键词：量子点制备表面修饰荧光

Abipartite molecular module controls cell death activation in the basal cell lineage of plant embryos

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Abipartite molecular module controls cell death activation i...

2013全国植物生物学大会

作者： ZHAO Peng ZHOU Xuemei ZHANG Liyao WANG Wei ma Ligang YANG libo PENG Xiongbo Peter V.Bozhkov SUN Mengxiang Department of Cell and Developmental Biology College of Life ScienceState Key Laboratory of Plant Hybrid RiceWuhan University Department of Plant Biology and Forest Genetics Uppsala BioCenterSwedish University of Agricultural Sciences and Linnean Center for Plant BiologyUppsalaSweden

Plant zygote divides asymmetrically into an apical cell that develops into the embryo proper and a basal cell that generates the suspensor,a vital organ functioning as a conduit of nutrients and growth factors to the embryo *** the suspensor has fulfilled its function, it is removed by programmed cell death(PCD) at the late stages of *** molecular trigger of this PCD is *** we use tobacco(Nicotiana tabacum) embryogenesis as a model system to demonstrate that the mechanism triggering suspensor PCD is based on the antagonistic action of two proteins:a protease inhibitor,cystatin NtCYS,and its target,cathepsin H-like protease *** is expressed in the basal cell of the proembryo,where encoded cystatin binds to and inhibits NtCP14,thereby preventing precocious onset of PCD. The anti-cell death effect of NtCYS is transcriptionally regulated and is repressed at the 32- celled embryo stage,leading to increased NTCP14 activity and initiation of *** of NtCYS or overexpression of NtCP14 induces precocious cell death in the basal cell lineage causing embryonic arrest and seed ***,overexpression of NtCYS or silencing of NtCP14 leads to profound delay of suspensor *** results demonstrate that NtCYS-mediated inhibition of NtCP14 protease acts as a bipartite molecular module to control initiation of PCD in the basal cell lineage of plant embryos.

关键词： embryogenesis suspensor programmed cell death cystatin cathepsin tobacco

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马克思主义引入中国的文化价值

社会主义研究 2008年第1期 31-34页

作者：刘力波马启民西北政法大学哲学与社会发展学院讲师陕西师范大学政治经济学院院长

近代中国文化生态的剧变表现为:文化传播与交流机制破坏;文化传承与变迁脉络割裂;近代文化片面发展。这凸现了中华民族精神的严重危机,并催生出中华民族解除精神危机的迫切文化需要,包括:高扬主体意识,为民族复兴奠定文化基础;自觉进行... 详细信息

近代中国文化生态的剧变表现为:文化传播与交流机制破坏;文化传承与变迁脉络割裂;近代文化片面发展。这凸现了中华民族精神的严重危机,并催生出中华民族解除精神危机的迫切文化需要,包括:高扬主体意识,为民族复兴奠定文化基础;自觉进行文化选择,重构文化发展机制;调适文化心态,走理性的民族精神复兴之路;以科学的世界观和方法论指导民族精神振兴。而马克思主义中国化正是对此需要的巧妙应答,其文化价值体现为:创造性化解文化两难困境;"世界历史"条件下重构文化发展机制;推动文化与政治、经济、社会协调发展。

关键词：马克思主义中国化文化生态中华民族精神文化价值

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汉语发展性阅读障碍儿童语素理解研究

中国特殊教育 2009年第5期 93-96页

作者：隋雪马立波王彦辽宁师范大学教育学院大连116029 大连大学初等师范学院大连116300

本研究通过比较汉语发展性阅读障碍儿童和阅读正常儿童完成同音语素理解任务的情况,来测查汉语发展性阅读障碍儿童的语素理解能力。结果发现,不同年级、不同性别的阅读障碍组判断成绩都比阅读正常组差,且差异显著。研究的结果提示我们,... 详细信息

本研究通过比较汉语发展性阅读障碍儿童和阅读正常儿童完成同音语素理解任务的情况,来测查汉语发展性阅读障碍儿童的语素理解能力。结果发现,不同年级、不同性别的阅读障碍组判断成绩都比阅读正常组差,且差异显著。研究的结果提示我们,汉语发展性阅读障碍儿童语素理解存在缺陷,支持汉语的语素意识缺陷是汉语发展性阅读障碍的原因。

关键词：发展性阅读障碍语素语素理解

核壳结构镍基纳米催化剂的制备及其在肉桂醛加氢反应中的性能

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化工学报 2017年第11期68卷 4161-4168页

作者：牛立博刘辰马苑媛张慧玲白国义河北大学化学与环境科学学院河北保定071002

分别以硝酸镍和氯化镍为镍源,利用热分解法和水合肼还原法制得镍纳米粒子,再经模板剂造孔法在镍核外部包裹一层介孔壳,通过焙烧和氢气还原制备了核壳结构催化剂Ni@mSiO_2和Ni-N2H4@mSiO_2,并以肉桂醛加氢为探针反应考察了核壳结构镍基... 详细信息

分别以硝酸镍和氯化镍为镍源,利用热分解法和水合肼还原法制得镍纳米粒子,再经模板剂造孔法在镍核外部包裹一层介孔壳,通过焙烧和氢气还原制备了核壳结构催化剂Ni@mSiO_2和Ni-N2H4@mSiO_2,并以肉桂醛加氢为探针反应考察了核壳结构镍基催化剂与负载型镍基催化剂的加氢性能。结果表明,核壳结构镍基催化剂在肉桂醛加氢反应中比共沉淀法制备的负载型镍基催化剂具有更高的活性,氢化肉桂醛的收率可达90%以上。同时,Ni-N_2H_4@mSiO_2催化剂具有较高的磁饱和度,可实现该催化剂在反应后高效回收并循环套用。采用X射线衍射、比表面及孔分析、透射电子显微镜、H_2-程序升温还原和H_2-化学吸附等表征手段,研究了所制催化剂的结构特征,初步探讨了催化剂结构与性能的构效关系。

关键词：催化剂纳米粒子加氢核壳结构构效关系

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一种适用于高动态的高精度频率估计方法

无线电工程 2021年第2期51卷 168-172页

作者：马立波陈敬乔北京跟踪与通信技术研究所北京100094 中国电子科技集团公司第五十四研究所河北石家庄050081

针对现有无线通信系统面对高动态情况下产生的大多普勒频移,而接收端频率估计精度不高,从而降低后续解调性能的问题,提供一种结合发送端插入导频符号的变采样率高精度频率估计方法,并进行了仿真。仿真结果表明,该频率估计方法可在充分... 详细信息

针对现有无线通信系统面对高动态情况下产生的大多普勒频移,而接收端频率估计精度不高,从而降低后续解调性能的问题,提供一种结合发送端插入导频符号的变采样率高精度频率估计方法,并进行了仿真。仿真结果表明,该频率估计方法可在充分利用时间同步导引情况下,估计精度可达到符号率的2%,多普勒变化率跟踪范围可达到符号率的一半,满足后续载波恢复对频偏的要求。

关键词：频率估计高动态快速傅里叶变换解调

Atmospheric Moisture Distribution and Transport over the Tibetan Plateau and the Impacts of the South Asian Summer Monsoon

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Acta meteorologica Sinica 2013年第6期27卷 819-831页

作者：周立波朱金焕邹捍马舒坡李鹏张宇霍翠萍 LAPC Institute of Atmospheric Physics Chinese Academy of Sciences

In this study, by using the ECMWF ERA-Interim reanalysis data from 1979 to 2010, the spatial distribution and transport of total atmospheric moisture over the Tibetan Plateau（TP） are analyzed, together with the associated impacts of the South Asian summer monsoon（SASM）. Acting as a moisture sink in summer, the TP has a net moisture flux of 2.59× 107kg s 1during 1979–2010, with moisture supplies mainly from the southern boundary along the latitude belts over the Bay of Bengal and the Arabian Sea. The total atmospheric moisture over the TP exhibits significant diferences in both spatial distribution and transport between the monsoon active and break periods and between strong and weak monsoon years. Large positive（negative） moisture anomalies occur over the southwest edge of the TP and the Arabian Sea, mainly due to transport of easterly（westerly） anomalies during the monsoon active（break） period. For the whole TP region, the total moisture supply is more strengthened than the climatological mean during the monsoon active period, which is mainly contributed by the transport of moisture from the south edge of the TP. During the monsoon break period, however, the total moisture supply to the TP is slightly weakened. In addition, the TP moisture sink is also strengthened（weakened） in the strong（weak） monsoon years, mainly attributed by the moisture transport in the west-east directions. Our results suggest that the SASM has exerted great impacts on the total atmospheric moisture and its transport over the TP through adjusting the moisture spatial distribution.

关键词： Tibetan Plateau moisture transport South Asian summer monsoon

太阳能蒸汽发生装置及碳基光热转换材料研究进展

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粉末冶金工业 2022年第4期32卷 85-88页

作者：杨小林马立波常州工程职业技术学院江苏常州213164

能源的消耗一直是困扰人们的一个问题,大约80%左右的能源属于不可再生能源,而这当中化石燃料有着主导地位,自从工业革命以来,经过多年的开采,化石燃料越来越少,清洁能源的开发受到了广泛的关注。太阳变成了重要的能源提供中心,为此各类... 详细信息

能源的消耗一直是困扰人们的一个问题,大约80%左右的能源属于不可再生能源,而这当中化石燃料有着主导地位,自从工业革命以来,经过多年的开采,化石燃料越来越少,清洁能源的开发受到了广泛的关注。太阳变成了重要的能源提供中心,为此各类光热转换材料逐渐被开发出来。在这些材料当中,碳基材料由于其本身自带的大量优点如材料便宜,吸光性能较高,具有热稳定性等,被广泛应用在太阳能光热转换器中,因此着重介绍了碳基材料作为太阳能光热转换材料的应用研究发展。

关键词：碳基材料光热转换研究进展

Noninvasive fluid bubble detection based on capacitive micromachined ultrasonic transducers

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Microsystems & Nanoengineering 2023年第1期9卷 115-126页

作者： Jiawei Yuan Zhikang Li Qi ma Jie Li Zixuan Li Yihe Zhao Shaohui Qin Xuan Shi libo Zhao Ping Yang Guoxi Luo Xiaozhang Wang Kwok Siong Teh Zhuangde Jiang State Key Laboratory for manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement TechnologiesXi’an Jiaotong University(Yantai)Research Institute for Intelligent Sensing Technology and SystemsXi’an Jiaotong University710049Xi’anChina School of Mechanical Engineering Xi’an Jiaotong University710049Xi’anChina Shandong Laboratory of Yantai Advanced materials and Green manufacturing 265503YantaiChina School of Mechanical and Electrical Engineering Shaanxi University of Science and TechnologyXi’an710049Xi’anChina School of Engineering San Francisco State UniversitySan FranciscoCA94132USA

Ultrasonic fluid bubble detection is important in industrial controls,aerospace systems and clinical medicine because it can prevent fatal mechanical failures and threats to ***,current ultrasonic technologies for bubble detection are based on conventional bulk PZT-based transducers,which suffer from large size,high power consumption and poor integration with ICs and thus are unable to implement real-time and long-term monitoring in tight physical spaces,such as in extracorporeal membrane oxygenation(ECMO)systems and dialysis machines or hydraulic systems in *** work highlights the prospect of capacitive micromachined ultrasonic transducers(CMUTs)in the aforementioned application situations based on the mechanism of received voltage variation caused by bubble-induced acoustic energy *** corresponding theories are established and well validated using finite element *** fluid bubbles inside a pipe with a diameter as small as 8 mm are successfully measured using our fabricated CMUT chips with a resonant frequency of 1.1 *** received voltage variation increases significantly with increasing bubble radii in the range of 0.5–2.5 *** studies show that other factors,such as bubble positions,flow velocities,fluid medium types,pipe thicknesses and diameters,have negligible effects on fluid bubble measurement,demonstrating the feasibility and robustness of the CMUT-based ultrasonic bubble detection technique.

关键词： bubble negligible mentioned