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Nanoscale control of silks for regular hydroxyapatite formation

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Progress in Natural Science:Materials International 2012年第2期22卷 115-119页

作者： Xingliang He a,Xiaowei Huang b,Qiang Lu b,Shuling Bai a,Hesun Zhu c a College of Basic Medical Science,chinese Medical university,Shenyang 110001,People’s Republic of{2. b National Engineering Laboratory for Modern Silk,College of Textile and Clothing Engineering,Soochow university,Suzhou 2.512.,People’s Republic of{2. c Research Center of Materials Science,beijing Institute of Technology,beijing 100081,People’s Republic of{2. [a] College of Basic Medical Science Chinese Medical University Shenyang 110001 People's Republic of China [b] National Engineering Laboratory for Modern Silk College of Textile and Clothing Engineering Soochow University Suzhou 215123 People's Republic of China [c] Research Center of Materials Science Beijing Institute of Technology Beijing 100081 People's Republic of China

The control of nanoparticle shape is still a challenge for different hydroxyapatite(HA) preparation *** the present study,silk fibroin with regular nanostructures was firstly prepared and then employed to regulate the mineralization of HA *** morphology and crystal structure of the deposition were investigated by SEM,X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR).Compared to previous studies in which silk fibroin with different nanostructures was used as template,the present study revealed that the HA nanoparticle shape could be controlled through regulating the nanostructure of silk *** silk nanospheres as template,the shape of HA gradually changed from pin-like structure to rice-like structure following the increase of silk fibroin *** some HA nanofibers were prepared with short silk nanofibers as *** results indicated that it is feasible to achieve the shape control of HA nanoparticles through further regulating the nanostructure of silk fibroin template,which would greatly facilitate the application of HA in different fields.

关键词： Silk fibroin Hydroxyapatite Shape control Biomineralization

Modulation of theta and gamma oscillations in central olfactory pathway by behavioral state

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Modulation of theta and gamma oscillations in central olfact...

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： Qing LIU~(1,3),Rui-Qi WU~(1,3),An-An LI~1,Fu-Qiang XU~(1,2.*) 1 Wuhan MRC,State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics,Wuhan Institute of Physics and Mathematics,the chinese academy of Science,Wuhan 430071,{2. 2.Wuhan National Laboratory for Optoelectronics,Wuhan 430074,{2. 3 graduate university of chinese academy of Science,beijing 10004.,{2.

＜正＞Objective In mammalian olfactory pathway,the oscillatory activities of the olfactory bulb（OB）,piriform cortex（PCX）and hippocampus（HPC）have been extensively studied to elucidate odor information processing. However,less is known about the oscillations of spontaneous activity and the modulation by behavioral state, especially for the theta（4-12.Hz）and gamma（35-100 Hz）*** In the present study,local field potentials （LFP）of spontaneous activity were recorded from the OB,PCX and HPC simultaneously in awake and anesthetized *** Compared with the anesthetized state,awake mice showed increased theta and gamma oscillations in all the three regions,but decreased coherences among ***,the spontaneous activities in exploratory walking and motionless mice were *** exploratory state,the power of theta oscillations in the PCX and HPC was decreased,whereas the power of theta in the OB and gamma in all regions were increased significantly. However,the coherences among the three brain regions for both theta and gamma oscillations were significantly *** was also found that the coherence between the PCX and the HPC was always the highest regardless of brain *** These results suggest that the theta and gamma oscillations in central olfactory pathway could be modulated by behavioral state,and that the higher coherences of both theta and gamma oscillations between PCX and HPC indicate tighter functional coupling between them.

关键词： oscillation olfactory bulb piriform cortex hippocampus functional coupling

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催化剂颗粒流的基本方程及其应用(Ⅱ)

化工冶金 1989年第4期10卷 13-23页

作者：周世辉中国石油大学北京研究生部

本文将催化剂颗粒流的基本方程应用到套管流动、立管流动和平行平板间的流动当中,求出了它们的极限应力解,绘制了主应力谱图和滑移线谱图;讨论了这些流动系统中颗粒流动的"块状"流动机制;提出了颗粒流动系统中的层流和湍流两种流动形态... 详细信息

本文将催化剂颗粒流的基本方程应用到套管流动、立管流动和平行平板间的流动当中,求出了它们的极限应力解,绘制了主应力谱图和滑移线谱图;讨论了这些流动系统中颗粒流动的"块状"流动机制;提出了颗粒流动系统中的层流和湍流两种流动形态及其判别准则(f/a·Hs/R).另外,文章在分析了催化剂浅床流动规律的基础上。从理论上解释了"架桥"和反向压力梯度现象,并提出了应力增长函数的概念及其计算公式。这些结果对正确地设计和操作颗粒流动系统和移动床以及及时地排除所出现的故障提供了方法,

关键词：催化剂颗粒流基本方程

Synthesis and X-ray crystal structure of oxamido-bridged heterobinuclear Ni(Ⅱ)-Cu(Ⅱ) complexes

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chinese Journal of Chemistry 1994年第6期12卷 503-508页

作者： WEI, Ping-Rong JIA, Lu LIU, Chang-Rang FAN, Yao-TingDepartment of Chemistry, Zhengzhou university, Zhengzhou, Henan 450052. chinaGAO, SongResearch Center of Rare Earth Chemistry, Peking university, beijing 100871, china 1Department of Chemistry Zhengzhou University Zhengzhou Henan 450052 China2Research Center of Rare Earth Chemistry Peking University Beijing 100871 China

The two complexes [Ni(oxen)Cu(L)2.(ClO4)***2. (L=2.2.-bipyridyl(bpy), 1,10-phenanthroline(phen)) have been synthesized, where oxen is N,N'-bis(2.aminoethyl)oxamido di-anion. The crystal structure of [Ni(oxen)Cu(bpy)2.(ClO4)***3OH has been determined by X-ray diffraction method. The crystal is triclinic system, space group P1 with a=12.179(1),b=12.2.8(2., c=11.476(2. A, a=97.57(1), B=97.52.1), 7=80.2.(2., V=1669.04(67) A3, Z=2. Dcalcd=1.667 g/cm3. The structure has been refined to final R of 0.076 and Rw of 0.080, respectively. The complexes have an extended oxamido-bridged structure and consist of Ni(Ⅱ) ion in a square planar environment and Cu(Ⅱ) ion in a distorted octahedral environment.

关键词： N,N'-bis(2.aminoethyl)oxamidonickel(II) heterobinuclear complexes crystal structure.

Mandarin chinese Tone Recognition with an Artificial Neural Network

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Journal of Otology 2006年第1期1卷 30-34页

作者： LEE Chaoyang School of Hearing Speech and Language Sciences Ohio University Athens OH USA

Mandarin chinese tone patterns vary in one of the four ways, i.e, (1) high level; (2. rising; (3) low falling and rising; and (4) high falling. The present study is to examine the efficacy of an artificial neural network in recognizing these tone patterns. Speech data were recorded from 12.children (3-6 years of age) and 15 adults. All subjects were native Mandarin chinese speakers. The fundamental frequencies (F0) of each monosyllabic word of the speech data were extracted with an autocorrelation method. The pitch data(i.e., the F0 contours) were the inputs to a feed-forward backpropagation artificial neural network. The number of inputs to the neural network varied from 1 to 16 and the hidden layer of the network contained neurons that varied from 1 to 16 in number. The output of the network consisted of four neurons representing the four tone patterns of Mandarin chinese. After being trained with the Levenberg-Marquardt optimization, the neural network was able to successfully classify the tone patterns with an accuracy of about 90% correct for speech samples from both adults and children. The artificial neural network may provide an objective and effective way of assessing tone production in prelingually-deafened children who have received cochlear implants.

关键词： tone recognition artificial neural network tone production chinese

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土壤中稀土对有效氮形态分配和转化的影响

中国稀土学报 2004年第3期22卷 375-379页

作者：丁士明张自立梁涛孙琴中国科学院地理科学与资源研究所北京100101 安徽农业大学土化学安徽合肥230036 南京大学环境学院污染控制与资源化研究国家重点实验室江苏南京210093

在土壤旱作和淹水培养两种方式下 ,通过添加外源稀土研究了黄褐土中稀土对有效氮形态分配和转化的影响。结果表明 ,在旱培条件下 ,土壤中稀土含量的提高增加铵态氮和水解氮的含量 ,减少硝态氮的含量 ,两周内增加矿质态氮的含量 ,八周以... 详细信息

在土壤旱作和淹水培养两种方式下 ,通过添加外源稀土研究了黄褐土中稀土对有效氮形态分配和转化的影响。结果表明 ,在旱培条件下 ,土壤中稀土含量的提高增加铵态氮和水解氮的含量 ,减少硝态氮的含量 ,两周内增加矿质态氮的含量 ,八周以后则无显著影响 ;有效氮的含量在稀土含量较低时升高 ,高含量时则下降 ,实验确定外源稀土对旱培土壤有效氮作用的无观察效应浓度 (NOEC)为 44 3 .8mg·kg- 1 。在淹水培养条件下 ,稀土含量较低时对土壤铵态氮和水解氮含量无显著影响 ,含量较高时则降低铵态氮和水解氮含量 ,外源稀土对淹水土壤铵态氮和水解氮含量影响的无观察效应浓度分别为 171.2.,2.5 6.9mg·kg- 1 。分析表明 ,土壤中稀土含量的变化对氮素的影响在旱培条件下主要与稀土对土壤硝化过程作用有关 ,淹水条件下与稀土对土壤氨化过程作用有关。

关键词：土壤学氮素形态转化安全性评价黄褐土稀土

Prenatal morphine exposure inhibits GABAA receptor-mediated responses in day-old chicks

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Prenatal morphine exposure inhibits GABAA receptor-mediated ...

中国神经科学学会第四次会员代表大会暨第八届全国学术会议

作者： Juan JIANG~1,Nan SUI~(1,*),Meng-Ya WANG~(2.*) 1 The Key Laboratory of Mental Health,Institute of Psychology,chinese academy of {2.,beijing 100101,china 2.Cell Electrophysiology Laboratory,Wannan Medical College,Wuhu 2.1002.china

Objective Prenatal morphine exposure may alter developmental process of fetal brain through activation of opioid receptors during the critical *** pervious work has shown that embryonic day 5-8(E5-8) may be the critical period to impair learning and memory functions in day-old chicks due to prenatal morphine exposure,which may be related to developmental changes of y-aminobutyric acid(GABA) *** this work,intracellular recording was used to investigate the effect of early prenatal morphine exposure on GABAergic system in day-old *** Coronal sections of left forebrains(500 )μm),containing the intermediate medial mesopallium(IMM) which is intimately involved in the early learning processes,were prepared from domestic chicks(0-12.days old),which were from control group(no treatment) or from saline group(treated by intra-allantoic injection of saline in E5-8) or from morphine group(treated by intra-allantoic injection of morphine in E5-8).Results(1) Spontaneous inhibitory postsynaptic potentials(sIPSPs) were observed in IMM neurons from all groups,but the occurrence rate of sIPSPs from morphine group(6.9%,4/58 cells) was obviously lower than control group(2..6%,14/49 cells) or saline group(32.1%,18/56 cells)(P2. The evoked excitatory or inhibitory postsynaptic potentials(eEPSPs or eIPSPs) were elicited by local electrical stimuli at 0.1 Hz in the IMM *** induction rate of elPSPs from morphine group(2..6%,16/58) was also lower than control group(49.0%, 2./49 cells) or saline group(48.2.,2./56 cells)(P2.1s,n=11) were shorter than saline group(4.9±3.0s,n=8) or control group(4.8±3.0s,n=4)(P<0.05).(4) Muscimol (1 mM,a specific GA

关键词： chick early prenatal morphine exposure γ-aminobutyric acid intracellular recording intermediate medial mesopallium bicuculline muscimol synapse response

南刘寄奴中的一个新1,10-裂环愈创木烷型倍半萜(英文)

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中国天然药物 2012年第5期10卷 358-362页

作者：昝珂陈筱清屠鹏飞北京大学药学院天然药物及仿生药物国家重点实验室北京100191 首都医科大学中医药学院北京100069

目的:研究南刘寄奴中化学成分。方法:采用硅胶和 ODS 等柱层析分离手段以及半制备高效液相, 运用 NMR、MS 以及理化性质鉴定化合物的结构。结果:从南刘寄奴中分离得到 8 个化合物, 其结构鉴定为 3β-ethoxytanapartholide (1), ((4S*,5S... 详细信息

目的:研究南刘寄奴中化学成分。方法:采用硅胶和 ODS 等柱层析分离手段以及半制备高效液相, 运用 NMR、MS 以及理化性质鉴定化合物的结构。结果:从南刘寄奴中分离得到 8 个化合物, 其结构鉴定为 3β-ethoxytanapartholide (1), ((4S*,5S*)-dihydro-5-[(1R*, 2.*)-2.hydroxy-2.methyl-5-oxo-3-cyclopenten-1-yl]-3-methylene-4-(3-oxobutyl)-2.3H)-furanone) (2., ligucy-peronol (3), cyperusol C (4), santamarin (5), 1α, 2., 3α, 4α, 10α-pentahydroxyguaia-11(13)-ene-12. 6α-olide (6), balanophonin (7),methyl 3-(2.-hydroxy-4’-methoxyphenyl) propanoate (8)。结论:化合物 1 是新人工产物, 化合物 4 和 8 为首次从蒿属中分离得到, 化合物 2.3, 5–7 为首次从该植物中分离得到。

关键词：南刘寄奴蒿属化学成分 1,10-裂环愈创木烷型倍半萜

Monitoring Changes of Wetland and Landform in the Yangtze River Estuary over the Past 30 Years Using Multi-temporal Satellite Images

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Monitoring Changes of Wetland and Landform in the Yangtze Ri...

中国地理学会2.07年学术年会

作者： Xiaoping XIE~a Bihong FU~b a School of Resources and Planning.Qufu Normal university,Qufu,2.3165.china b Institute of Geology and Geophysics.{2. academy of sciences.beijing,10002.

＜正＞Spatio-temporal changes of wetland and landform in the Yangtze River Estuary are analyzed Based on multi-temporal satellite remote sensing data such as Landsat MSS. TM. ETM+ and ASTER during 1975 to 2.05.. Resul... 详细信息

关键词： Wetland landform evolution spatio-temporal change satellite remote sensing Yangtze River Estuary.