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表面In掺杂TiO2的N719/TiO2-Inx%/FTO薄膜电极的光电转换效率 被引量:6
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作者 程辉 姚江宏 曹亚安 《物理化学学报》 SCIE CAS CSCD 北大核心 2012年第11期2632-2640,共9页
采用溶胶-凝胶法制备出In表面修饰的TiO2(TiO2-Inx%)纳米粒子,x%代表在In掺杂的TiO2样品中In3+与In3+和Ti4+离子摩尔百分含量.利用二(四丁基铵)顺式-双(异硫氰基)双(2,2-联吡啶-4,4-二羧酸)钌(II)(N719)作为敏化剂,制备出N719/TiO2/FTO... 采用溶胶-凝胶法制备出In表面修饰的TiO2(TiO2-Inx%)纳米粒子,x%代表在In掺杂的TiO2样品中In3+与In3+和Ti4+离子摩尔百分含量.利用二(四丁基铵)顺式-双(异硫氰基)双(2,2-联吡啶-4,4-二羧酸)钌(II)(N719)作为敏化剂,制备出N719/TiO2/FTO(氟掺杂锡氧化物)和N719/TiO2-Inx%/FTO染料敏化薄膜电极.光电转换效率实验表明,在薄膜电极+0.5mol.L-1LiI+0.05mol.L-1I2的三甲氧基丙腈(MPN)溶液+Pt光电池体系中,N719/TiO2-Inx%/FTO薄膜电极的光电转换效率均高于N719/TiO2/FTO,其中N719/TiO2-In0.1%/FTO的光电转换效率比N719/TiO2/FTO提高了20%.利用X射线衍射(XRD)、X射线光电子能谱(XPS)、漫反射吸收光谱(DRS)、荧光(PL)光谱和表面光电流作用谱确定了TiO2-Inx%样品中In3+离子的存在方式和能带结构;利用表面光电流作用谱研究了N719/TiO2-Inx%/FTO薄膜电极的光致界面电荷转移过程.结果表明,In3+离子在TiO2表面形成O-In-Cln(n=1,2)物种,该物种的表面态能级位于导带下0.3eV处;在光电流产生过程中,O-In-Cln(n=1,2)表面态能级有效地抑制了光生载流子在TiO2-Inx%层的复合,促进了阳极光电流的增加,从而导致N719/TiO2-Inx%/FTO薄膜电极的光电转化效率高于N719/TiO2/FTO,并进一步讨论了光致界面电荷转移的机理. 展开更多
关键词 TiO2-Inx% O-In-Cln (n=1 2)物种 表面敏化 N719 TiO2-Inx% FTO 光电转换效率
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1-3型压电复合材料壳式聚焦换能器的研究 被引量:2
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作者 王科鑫 何敏 +2 位作者 郝琦 刘阳 曾德平 《功能材料》 EI CAS CSCD 北大核心 2016年第3期158-162,169,共6页
为解决压电陶瓷聚焦换能器阻抗高、带宽窄,电声转换效率低等问题,采用新型的1-3型压电复合材料作为聚焦超声换能器材料,设计并制作了一种新型的1-3压电复合材料壳式聚焦换能器。通过对新型换能器的频率特性,电声转换效率研究后和当前应... 为解决压电陶瓷聚焦换能器阻抗高、带宽窄,电声转换效率低等问题,采用新型的1-3型压电复合材料作为聚焦超声换能器材料,设计并制作了一种新型的1-3压电复合材料壳式聚焦换能器。通过对新型换能器的频率特性,电声转换效率研究后和当前应用的PZT壳式聚焦换能器进行对比,证明了1-3型压电复合材料壳式聚焦换能器的阻抗较低,相对带宽达61%,是PZT压电陶瓷壳式聚焦换能器的3.39倍,以及较高的电声转换效率η为54%,是PZT压电陶瓷壳式聚焦换能器的1.68倍。将换能器实际声场检测结果与Matlab声场仿真结果进行对比研究,得出换能器具有较好的声场特性及聚焦效果。为高性能的聚焦换能器的实现提供了理论及实验基础。 展开更多
关键词 1-3压电复合材料 聚焦换能器 电声转换效率 频率特性 声场特性
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黄曲霉毒素B1在乳畜中的转化 被引量:5
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作者 吴坤坦 齐德生 《饲料工业》 北大核心 2018年第20期59-64,共6页
黄曲霉毒素主要是由曲霉菌产生的一类具有高致癌性的次级代谢产物,我国饲料及饲料原料普遍受到黄曲霉毒素B1污染。乳畜摄入黄曲霉毒素B1后,代谢生成的羟基化产物黄曲霉毒素M1可通过乳汁污染乳及乳制品,并因这两种毒素都具有极强的毒性... 黄曲霉毒素主要是由曲霉菌产生的一类具有高致癌性的次级代谢产物,我国饲料及饲料原料普遍受到黄曲霉毒素B1污染。乳畜摄入黄曲霉毒素B1后,代谢生成的羟基化产物黄曲霉毒素M1可通过乳汁污染乳及乳制品,并因这两种毒素都具有极强的毒性越来越受到人们的关注。黄曲霉毒素B1在乳畜的肝脏、瘤胃和乳腺等部位均可代谢转化,黄曲霉毒素M1向乳中的转移受到多种因素的影响。文章从黄曲霉毒素B1的代谢与转移排泄、影响黄曲霉毒素M1的转化因素以及黄曲霉毒素B1对乳腺上皮细胞和瘤胃微生物的影响进行论述。 展开更多
关键词 黄曲霉毒素B1 瘤胃微生物 乳腺上皮细胞 黄曲霉毒素M1 转化效率
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Differential neuronal reprogramming induced by NeuroD1 from astrocytes in grey matter versus white matter 被引量:11
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作者 Min-Hui Liu Wen Li +3 位作者 Jia-Jun Zheng Yu-Ge Xu Qing He Gong Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第2期342-351,共10页
A new technology called in vivo glia-to-neuron conversion has emerged in recent years as a promising next generation therapy for neural regeneration and repair. This is achieved through reprogramming endogenous glial ... A new technology called in vivo glia-to-neuron conversion has emerged in recent years as a promising next generation therapy for neural regeneration and repair. This is achieved through reprogramming endogenous glial cells into neurons in the central nervous system through ectopically expressing neural transcriptional factors in glial cells. Previous studies have been focusing on glial cells in the grey matter such as the cortex and striatum, but whether glial cells in the white matter can be reprogrammed or not is unknown. To address this fundamental question, we express NeuroD1 in the astrocytes of both grey matter(cortex and striatum) and white matter(corpus callosum) to investigate the conversion efficiency, neuronal subtypes, and electrophysiological features of the converted neurons. We discover that NeuroD1 can efficiently reprogram the astrocytes in the grey matter into functional neurons, but the astrocytes in the white matter are much resistant to neuronal reprogramming. The converted neurons from cortical and striatal astrocytes are composed of both glutamatergic and GABAergic neurons, capable of firing action potentials and having spontaneous synaptic activities. In contrast, the few astrocyte-converted neurons in the white matter are rather immature with rare synaptic events. These results provide novel insights into the differential reprogramming capability between the astrocytes in the grey matter versus the white matter, and highlight the impact of regional astrocytes as well as microenvironment on the outcome of glia-toneuron conversion. Since human brain has large volume of white matter, this study will provide important guidance for future development of in vivo glia-to-neuron conversion technology into potential clinical therapies. Experimental protocols in this study were approved by the Laboratory Animal Ethics Committee of Jinan University(approval No. IACUC-20180321-03) on March 21, 2018. 展开更多
关键词 ASTROCYTE conversion efficiency corpus callosum cortex grey MATTER in vivo cell conversion NeuroD1 neuron REPROGRAMMING STRIATUM white MATTER
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基于1-3压电复合材料宽带超声换能器研究
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作者 高伟宸 曾涛 +2 位作者 罗曼 苏纯珍 曾德平 《压电与声光》 CAS 北大核心 2023年第4期607-613,共7页
电声转换效率与换能器带宽是评价聚焦超声换能器性能的重要指标。传统压电陶瓷制备的聚焦超声换能器,其电声转换效率与换能器带宽偏低。该文采用实验结合仿真模拟的方式,通过研究1-3压电复合材料中压电相的体积比、环氧相改性、调控匹... 电声转换效率与换能器带宽是评价聚焦超声换能器性能的重要指标。传统压电陶瓷制备的聚焦超声换能器,其电声转换效率与换能器带宽偏低。该文采用实验结合仿真模拟的方式,通过研究1-3压电复合材料中压电相的体积比、环氧相改性、调控匹配层阻抗与匹配层厚度对换能器性能的影响,开发了一种基于1-3压电复合材料的聚焦超声换能器,实现了82.3%的电声转换效率与140 kHz的换能器带宽。结果表明,与同等规格的传统压电陶瓷聚焦超声换能器相比,该超声换能器的两项指标分别提升了105%与250%,这为大功率聚焦超声换能器的设计开发提供了参考与指导。 展开更多
关键词 1-3压电复合材料 聚焦超声换能器 电声转换效率 换能器带宽 匹配层
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Maximum initial primary wave model for low-Froude-number reservoir landslides based on wave theory
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作者 LI Yang HUANG Bolin +2 位作者 QIN Zhen DONG Xingchen HU Lei 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2664-2680,共17页
The impulse waves induced by large-reservoir landslides can be characterized by a low Froude number.However,systematic research on predictive models specifically targeting the initial primary wave is lacking.Taking th... The impulse waves induced by large-reservoir landslides can be characterized by a low Froude number.However,systematic research on predictive models specifically targeting the initial primary wave is lacking.Taking the Shuipingzi 1#landslide that occurred in the Baihetan Reservoir area of the Jinsha River in China as an engineering example,this study established a large-scale physical model(with dimensions of 30 m×29 m×3.5 m at a scale of 1:150)and conducted scaled experiments on 3D landslide-induced impulse waves.During the process in which a sliding mass displaced and compressed a body of water to generate waves,the maximum initial wave amplitude was found to be positively correlated with the sliding velocity and the volume of the landslide.With the increase in the water depth,the wave amplitude initially increased and then decreased.The duration of pressure exertion by the sliding mass at its maximum velocity directly correlated with an elevated wave amplitude.Based on the theories of low-amplitude waves and energy conservation,while considering the energy conversion efficiency,a predictive model for the initial wave amplitude was derived.This model could fit and validate the functions of wavelength and wave velocity.The accuracy of the initial wave amplitude was verified using physical experiment data,with a prediction accuracy for the maximum initial wave amplitude reaching 90%.The conversion efficiency(η)directly determined the accuracy of the estimation formula.Under clear conditions for landslide-induced impulse wave generation,estimating the value ofηthrough analogy cases was feasible.This study has derived the landslide-induced impulse waves amplitude prediction formula from the standpoints of wave theory and energy conservation,with greater consideration given to the intrinsic characteristics in the formation process of landslide-induced impulse waves,thereby enhancing the applicability and extensibility of the formula.This can facilitate the development of empirical estimation methods for landslide-induced impulse waves toward universality. 展开更多
关键词 Three-dimensional physical model experiments Reservoir-landslide-induced impulse wave Energy conversion efficiency Landslide-induced impulse wave prediction model Shuipingzi 1#landslide
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Photoinhibition and Photooxidation in Leaves of indica and japonica Rice Under Different Temperatures and Light Intensities 被引量:5
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作者 季本华 焦德茂 《Acta Botanica Sinica》 CSCD 2001年第7期714-720,共7页
Physiological indices related to the efficiency (F-v/F-m) of light energy conversion in PS II and the peroxidation of membrane lipid were measured in leaves of Oryza sativa L. sp. indica rice cv. 'Shanyou 63' ... Physiological indices related to the efficiency (F-v/F-m) of light energy conversion in PS II and the peroxidation of membrane lipid were measured in leaves of Oryza sativa L. sp. indica rice cv. 'Shanyou 63' and sp. japonica rice cv. '9516'' under different temperatures and fight intensities for 4 days. No changes in F-v/F-m and membrane lipid peroxidation product (MDA) were observed, so neither photoinhibition nor photooxidation happened in both rice cultivars under moderate temperature and medium light intensity. However, F-v/F-m dropped obviously with no change in MDA contents, and photoinhibition appeared in indica rice cv. 'Shanyou 63' under medium temperature and strong light intensity. Furthermore, both photoinhibition and photooxidation were observed in two rice cultivars under chilling temperature and strong light intensity. Experiments with inhibitors under chilling temperature and strong light intensity showed that indica rice had a decrease in DI protein content and SOD activity, and the extent of inhibition of xanthophyll. cycle and nonphotochemical quenching (qN) was larger, and a higher level of MDA was observed. The photoinhibition and photooxidation in indica rice were more distinct as compared with japonica rice. The authors suggested that PS II light energy conversion efficiency (F-v/F-m) and membrane lipid peroxidation were the key indices for the detection of photooxidation. 展开更多
关键词 D1 protein efficiency of light energy conversion in PSII xanthophyll cycle non-photochemical quenching (qN) membrane lipid peroxidation RICE
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低压汞灯电光转化效率的水温特性测试研究
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作者 张军 李梦凯 +4 位作者 付志敏 张帆 李文涛 何志明 强志民 《中国给水排水》 CAS CSCD 北大核心 2023年第15期89-93,共5页
低压汞灯电光转化效率受水温影响,因此灯的水温特性对水处理紫外反应器的优化设计和运行维护至关重要。基于自行研制的荧光微探头和国际紫外线协会提出的空气中电光转化效率测试方法,提出低压汞灯电光转化效率水温特性测试方法并搭建测... 低压汞灯电光转化效率受水温影响,因此灯的水温特性对水处理紫外反应器的优化设计和运行维护至关重要。基于自行研制的荧光微探头和国际紫外线协会提出的空气中电光转化效率测试方法,提出低压汞灯电光转化效率水温特性测试方法并搭建测试装置,对4个厂家生产的低压汞灯进行测试。结果表明,所研发的方法可准确测定低压汞灯电光转化效率与水温的关系。当水温从5℃升高到35℃时,受试灯管电光转化效率整体呈现上升趋势。灯A、B在水和空气中的电光转化效率相近,灯C在水中的电光转化效率高于其在室温下的效率(35.5%),灯D在水和空气中的电光转化效率均最低。将空气中电光转化效率应用于水处理会造成误差,应针对实际应用场景,依据准确测定的低压汞灯水温特性,选择适宜的低压汞灯,提高效率并保障可靠性。 展开更多
关键词 低压汞灯 电光转化效率 水温特性 紫外反应器 水处理
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Effect of Fluorination on the Photovoltaic Properties of Medium Bandgap Polymers for Polymer Solar Cells
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作者 Huan Guo Wanbin Li +2 位作者 Chunmei Chang Xia Guo Maojie Zhang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2018年第6期502-506,共5页
Fluorination of conjugated polymers is one of the effective strategies to tune the molecular energy levels and morphology for high efficient polymer solar cells (PSCs). Herein, two novel donor-acceptor conjugated po... Fluorination of conjugated polymers is one of the effective strategies to tune the molecular energy levels and morphology for high efficient polymer solar cells (PSCs). Herein, two novel donor-acceptor conjugated polymers, PffBT and PBT, based on bis(3,5-bis(hexyloxy)phenyl)benzo[1,2- b:4,5-b']dithiophene and benzo[c][1,2,5]thiadiazole (BT) with or without fluorination, respectively, were synthesized, and their photovoltaic properties were compared. The polymer PffBT based on fluorinated BT showed lower frontier energy levels, improved polymer ordering, and a well-developed fibril structure in the blend with PC71BM. As a result, the PSCs based on PffBT/PC71BM exhibit a superior power conversion efficiency (PCE) of 8.6% versus 4.4% for PBT-based devices, due to a high space charge limit current (SCLC) hole mobility, mixed orientation of polymer crystals in the active layer, and low bimolecular recombination. 展开更多
关键词 benzo[c][1 2 5]thiadiazole conjugated polymers FLUORINATION polymer solar cells power conversion efficiency
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Experiments and analysis of gold disk targets irradiated by smoothing beams of Xingguang Ⅱ facilities with 350 nm wavelength
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作者 JIANG ShaoEn ZHANG BaoHan +5 位作者 LIU ShenYe YANG JiaMin SUN KeXu HUANG TianXuan DING YongKun ZHENG ZhiJian 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期716-730,共15页
Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-Ⅱ) laser facilities with 350 nm wavelength,0.6 ns pulse width and 20-80 Joules energies. Laser absorption,light scattering ... Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-Ⅱ) laser facilities with 350 nm wavelength,0.6 ns pulse width and 20-80 Joules energies. Laser absorption,light scattering and X-ray conversion were experimentally investigated. The experimental results showed that laser ab-sorption and scattered light were about 90% and 10%,respectively,under focusing irradiation,but the laser absorption increased 5%-10% and the scattered light about 1% under the condition of beam smoothing. Compared with the case of fo-cusing irradiation,the laser absorption was effectively improved and the scattered light remarkably dropped under uniform irradiation; then due to the decrease in laser intensity,X-ray conversion increased. This is highly advantageous to the in-ertial confinement fusion. However,X-ray conversion mechanism basically did not change and X-ray conversion efficiency under beam smoothing and focusing irra-diation was basically the same. 展开更多
关键词 beam smoothing lens array laser absorption scattered light X-ray conversion
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