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一种基于三角数分解的可配置2-D卷积器优化方法
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作者 黄继业 肖强 +4 位作者 田大海 高明裕 王俊帆 董哲康 黄汐威 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第7期3054-3062,共9页
多尺寸2-D卷积通过特征提取在检测、分类等计算机视觉任务中发挥着重要作用。然而,目前缺少一种高效的可配置2-D卷积器设计方法,这限制了卷积神经网络(CNN)模型在边缘端的部署和应用。该文基于乘法管理以及奇平方数的三角数分解方法,提... 多尺寸2-D卷积通过特征提取在检测、分类等计算机视觉任务中发挥着重要作用。然而,目前缺少一种高效的可配置2-D卷积器设计方法,这限制了卷积神经网络(CNN)模型在边缘端的部署和应用。该文基于乘法管理以及奇平方数的三角数分解方法,提出一种高性能、高适应性的卷积核尺寸可配置的2-D卷积器。所提2-D卷积器包含一定数量的处理单元(PE)以及相应的控制单元,前者负责运算任务,后者负责管理乘法运算的组合,二者结合以实现不同尺寸的卷积。具体地,首先根据应用场景确定一个奇数列表,列表中为2-D卷积器所支持的尺寸,并利用三角数分解得到对应的三角数列表;其次,根据三角数列表和计算需求,确定PE的总数量;最后,基于以小凑大的方法,确定PE的互连方式,完成电路设计。该可配置2-D卷积器通过Verilog硬件描述语言(HDL)设计实现,由Vivado 2 022.2在XCZU7EG板卡上进行仿真和分析。实验结果表明,相比同类方法,该文所提可配置2-D卷积器,乘法资源利用率得到显著提升,由20%~50%提升至89%,并以514个逻辑单元实现1 500 MB/s的吞吐率,具有广泛的适用性。 展开更多
关键词 2-d卷积器 可配置架构 乘法管理 三角数分解
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基于二萘并[2,3-B∶2′,3′-D]呋喃基团的高效窄发射蓝光OLED器件
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作者 王小伟 袁江波 +4 位作者 马佩兰 闫自强 崔志远 孙军 彭其明 《发光学报》 EI CAS CSCD 北大核心 2024年第9期1503-1510,共8页
高效率窄光谱蓝色有机电致发光器件(OLED)是柔性显示领域的研究重点之一。本文以二萘并[2,3-B∶2′,3′-D]呋喃为弱电子受体、N-(4-联苯基)-1-萘胺作为电子给体设计合成了一种D-A-D型蓝光分子DPF-NA,其在正己烷溶液中的发射峰位于441 n... 高效率窄光谱蓝色有机电致发光器件(OLED)是柔性显示领域的研究重点之一。本文以二萘并[2,3-B∶2′,3′-D]呋喃为弱电子受体、N-(4-联苯基)-1-萘胺作为电子给体设计合成了一种D-A-D型蓝光分子DPF-NA,其在正己烷溶液中的发射峰位于441 nm。理论计算与光物理测试结果显示DPF-NA具有杂化局域电荷转移激发态(HLCT)特性,兼具局域态(LE)高发光效率与电荷转移态(CT)高激子利用率特征,在二氯甲烷溶液中的光致发光量子效率(PLQY)为81.2%。基于质量分数3%DPF-NA掺杂浓度的OLED器件电致发光(EL)峰位于455 nm,半峰宽(FWHM)仅为26 nm,CIE(x,y)坐标为(0.14,0.08),最大外量子效率(EQEmax)为6.76%。 展开更多
关键词 有机电致发光器件 二萘并[2 3-B∶2′ 3′-d]呋喃 蓝光 激子利用 外量子效率
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New 4-imino-4H-Chromeno[2,3-d]Pyrimidin-3(5H)-Amine: Synthesis, Cytotoxic Effects on Tumoral Cell Lines and in Silico ADMET Properties
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作者 Marwa Dhiabi Sirine Karoui +7 位作者 Mehdi Fakhfakh Souhir Abid Emmanuelle Limanton Rémy Le Guével Thierry Charlier Ludovic Paquin Jean-Pierre Bazureau Houcine Ammar 《International Journal of Organic Chemistry》 2024年第3期107-122,共16页
The synthesis of new 4-imino-4H-chromeno[2,3-d]pyrimidin-3(5H)-amine in four steps including one step under microwave dielectric heating is reported. The structural identity of the synthesized compounds was establishe... The synthesis of new 4-imino-4H-chromeno[2,3-d]pyrimidin-3(5H)-amine in four steps including one step under microwave dielectric heating is reported. The structural identity of the synthesized compounds was established according to their spectroscopic analysis, such as FT-IR, NMR and mass spectroscopy. These new compounds were tested for their antiproliferative activities on seven representative human tumoral cell lines (Huh7 D12, Caco2, MDA-MB231, MDA-MB468, HCT116, PC3 and MCF7) and also on fibroblasts. Among them, only the compounds 6c showed micromolar cytotoxic activity on tumor cell lines (1.8 50 50 > 25 μM). Finally, in silico ADMET studies ware performed to investigate the possibility of using of the identified compound 6c as potential anti-tumor compound. 展开更多
关键词 2-Amino-4H-Chromene 4H-Chromeno[2 3-d]Pyrimidin-3(5H)-Amine Microwave Irradiation Tumoral Cell Line in Silico ADMET
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2-D Modeling and Calculations of Stratospheric Ozone and Influences of Convection, Diffusion, and Time
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作者 Ibraheem Alelmi Laurie Wei Sen Nieh 《Atmospheric and Climate Sciences》 2024年第2期250-276,共27页
An engineering system approach of 2-D cylindrical model of transient mass balance calculations of ozone and other concerned chemicals along with fourteen photolysis, ozone-generating and ozone-depleting chemical react... An engineering system approach of 2-D cylindrical model of transient mass balance calculations of ozone and other concerned chemicals along with fourteen photolysis, ozone-generating and ozone-depleting chemical reaction equations was developed, validated, and used for studying the ozone concentrations, distribution and peak of the layer, ozone depletion and total ozone abundance in the stratosphere. The calculated ozone concentrations and profile at both the Equator and a 60˚N location were found to follow closely with the measured data. The calculated average ozone concentration was within 1% of the measured average, and the deviation of ozone profiles was within 14%. The monthly evolution of stratospheric ozone concentrations and distribution above the Equator was studied with results discussed in details. The influences of slow air movement in both altitudinal and radial directions on ozone concentrations and profile in the stratosphere were explored and discussed. Parametric studies of the influences of gas diffusivities of ozone D<sub>O3</sub> and active atomic oxygen D<sub>O</sub> on ozone concentrations and distributions were also studied and delineated. Having both influences through physical diffusion and chemical reactions, the diffusivity (and diffusion) of atomic oxygen D<sub>O</sub> was found to be more sensitive and important than that of ozone D<sub>O3</sub> on ozone concentrations and distribution. The 2-D ozone model present in this paper for stratospheric ozone and its layer and depletion is shown to be robust, convenient, efficient, and executable for analyzing the complex ozone phenomena in the stratosphere. . 展开更多
关键词 Stratospheric Ozone 2-d Model Ozone Layer Ozone Depletion CONVECTION DIFFUSION
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NMR Parameters and Vibrational Investigation of 2-Dicyanovinyl-5-(4-ethoxyphenyl) thiophene by ab initio HF and DFT Calculations 被引量:1
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作者 张瑞州 李小红 张现周 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第10期1395-1408,共14页
Optimized geometry and harmonic vibrational frequency of 2-dicyanovinyl-5-(4- ethoxyphenyl)thiophene (C16Hj2N2OS) are calculated at the HF/6-31++G(d,p) and B3LYP/6- 311 ++G(d,p) levels. Mulliken charges in... Optimized geometry and harmonic vibrational frequency of 2-dicyanovinyl-5-(4- ethoxyphenyl)thiophene (C16Hj2N2OS) are calculated at the HF/6-31++G(d,p) and B3LYP/6- 311 ++G(d,p) levels. Mulliken charges in the ground state are also calculated. The research shows the presence of intermolecular interaction in the title compound. The scaled harmonic vibrational frequencies have been compared with experimental FT-IR spectra. A detailed interpretation of the infrared spectra of the title compound is reported. The theoretical spectrograms for IR spectra of the title compound have been constructed, The isotropic chemical shift computed by 13C and 1H NMR analyses also shows good agreement with the experimental observations. 展开更多
关键词 2-dicyanovinyl-5-(4-ethoxyphenyl)thiophene vibrational spectra
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Electronic Absorption Spectra and Third-Order Nonlinear Optical Property of Dinaphtho[2,3-b:2’,3’-d]Thiophene-5,7,12,13- Tetraone (DNTTRA) and Its Phenyldiazenyl Derivatives: DFT Calculations 被引量:1
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作者 Ziran Chen Yujin Zhang +3 位作者 Zhanrong He Yonghua Guan Yuan Li Hongping Li 《Computational Chemistry》 2020年第4期43-60,共18页
Third-order nonlinear optical (NLO) materials have broad application prospects in high-density data storage, optical computer, modern laser technology, and other high-tech industries. The structures and frequencies of... Third-order nonlinear optical (NLO) materials have broad application prospects in high-density data storage, optical computer, modern laser technology, and other high-tech industries. The structures and frequencies of Dinaphtho[2,3-b:2’,3’-d]thiophene-5,7,12,13-tetraone (DNTTRA) and its 36 derivatives containing azobenzene were calculated by using density functional theory B3LYP and M06-2X methods at 6-311++g(d, p) level, respectively. Besides, the atomic charges of natural bond orbitals (NBO) were analyzed. The frontier orbitals and electron absorption spectra of A-G5 molecule were calculated by TD-DFT (TD-B3LYP/6-311++g(d, p) and TD-M06-2X/6-311++g(d, p)). The NLO properties were calculated by effective finite field FF method and self-compiled program. The results show that 36 molecules of these six series are D-π-A-π-D structures. The third-order NLO coefficients γ (second-order hyperpolarizability) of the D series molecules are the largest among the six series, reaching 10<sup>7</sup> atomic units (10<sup><span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#ffffff;"="">-</span>33</sup> esu) of order of magnitude, showing good third-order NLO properties. Last, the third-order NLO properties of the azobenzene ring can be improved by introducing strong electron donor groups (e.g. -N(CH<sub>3</sub>)<sub>2</sub> or -NHCH<sub>3</sub>) in the azobenzene ring, so that the third-order NLO materials with good performance can be obtained. 展开更多
关键词 AZOBENZENE Dinaphtho[2 3-b:2 3’-d]thiophene-5 7 12 13-Tetraone Density Functional Theory Electronic Absorption Spectra Third-Order Nonlinear Optical Property
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Synthesis and Crystal Structure of 2,5-Dimorpholinyl-3,4-di(p-chlorophenyl)thiophene
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作者 王香善 邹建平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第6期444-446,共3页
The title compound 2,5-dimorpholinyl-3,4-di(p-chlorophenyl)thiophene (C24H24Cl2N2O2S, Mr=475.41) was obtained by the reaction of a-(p-chlorothiobenzoyl)- thioformmorpholine with trimethyl phosphite. The crystal is tri... The title compound 2,5-dimorpholinyl-3,4-di(p-chlorophenyl)thiophene (C24H24Cl2N2O2S, Mr=475.41) was obtained by the reaction of a-(p-chlorothiobenzoyl)- thioformmorpholine with trimethyl phosphite. The crystal is triclinic, space group Pī, with unit cell constants a=6.074(1), b=10.325(1), c=19.779(2)? a=76.74(1), b=87.11(1), g=74.92(1), Z=2, V=1165.7(3)?, Dc=1.354g穋m-3, m (MoKa)=0.392mm-1, F(000)=496, R=0.0324, Rw=0.0458 for 3102 observed reflections(I>2s(I)). X-ray analysis reveals that interatomic distances for C(7)C(19) and C(8)C(20) are 1.368(2) and 1.365(2)? respectively, which shows that they are C=C double bonds. The atoms of C(7), C(8), C(19), C(20) and S form a thiophene ring and the morpholine adopts chair conformation. 展开更多
关键词 crystal structure 2 5-dimorpholinyl-3 4-di(p-chlorophenyl) thiophene synthesis
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抗癌药中间体2-噻吩甲酸制备新工艺研究
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作者 姜维佳 雷伟 +2 位作者 陈杰 王青 王玉高 《现代化工》 CAS CSCD 北大核心 2024年第6期175-180,共6页
在促进剂K_(2)CO_(3)/TiO_(2)的作用下,通过二氧化碳的羧基化反应成功地将噻吩转化为2-噻吩甲酸,并优化了合成条件,考察了促进剂K_(2)CO_(3)/TiO_(2)的结构、性质对合成路线的影响。结果表明,K_(2)CO_(3)/TiO_(2)起主要促进作用的为表... 在促进剂K_(2)CO_(3)/TiO_(2)的作用下,通过二氧化碳的羧基化反应成功地将噻吩转化为2-噻吩甲酸,并优化了合成条件,考察了促进剂K_(2)CO_(3)/TiO_(2)的结构、性质对合成路线的影响。结果表明,K_(2)CO_(3)/TiO_(2)起主要促进作用的为表面无定型K_(2)CO_(3);考虑到产物的热稳定性,反应温度不宜超过300℃;产物在反应刚开始的1 h内大量生成,此后生成速率急速下降。该研究不仅开发了新颖、环保和高效的2-噻吩甲酸合成路线,还拓展了二氧化碳的高效利用途径。 展开更多
关键词 2-噻吩甲酸 抗癌药中间体 二氧化碳 羧基化 合成
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Synthesis and Crystal Structure of 2-(3,3'-Bithiophen-2,2'-yl)dibenzothiazole (BTDB) and 2-(Dithieno[2,3-b:3',2' -d]thiophen-2,5-yl)dibenzothiazole (DTTDB) 被引量:1
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作者 李春丽 杨娟娟 +1 位作者 史建武 王华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第6期877-884,共8页
The title compounds, 2-(3,3'-bithiophen-2,2'-yl)dibenzothiazole (BTDB) and 2-(dithieno[2,3-b:3',2'-d]thiophen-2,5-yl)dibenzothiazole (DTTDB), have been synthesized and characterized by FT-IR, NMR, MS, HRM... The title compounds, 2-(3,3'-bithiophen-2,2'-yl)dibenzothiazole (BTDB) and 2-(dithieno[2,3-b:3',2'-d]thiophen-2,5-yl)dibenzothiazole (DTTDB), have been synthesized and characterized by FT-IR, NMR, MS, HRMS and X-ray single-crystal diffraction. The crystal of BTDB crystallizes in triclinic, space group P1 with a = 9.2207(17), b = 10.453(2), c = 10.969(2) A, V= 981.2(3) A3 and Z = 2. Crystal data of DTTDB: orthorhombic system, space group Pbcn with a = 4.5290(8), b = 13.576(3), c = 32.033(6) A, V= 1969.6(6) A3 and Z = 4. 展开更多
关键词 synthesis crystal structure 2-(3 3'-bithiophen-2 2'-yl)dibenzothiazole 2-(dithieno [2 3-b:3' 2-d] thiophen-2 5-yl)dihenzothiazole
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Photocatalytic Oxidation Kinetics of Thiophene with Nano-F^-/Fe^(3+)/TiO_2 被引量:2
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作者 Li Fatang~1 Sun Zhimin~1 +3 位作者 Liu Ying~1 Zhao Dishun~2 Liu Ruihong~1 (1.College of Science,Hebei University of Science and Technology,Shijiazhuang 050018 2.College of Chemical and Pharmaceutical Engineering,Hebei University of Science and Technology) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第4期48-52,共5页
Photocatalytic oxidation kinetics of thiophene in n-octane/water extraction system was studied with fluorine and ferric ion codoped nano-TiO_2(nano-F^-/Fe^(3+)/TiO_2) powders used as the photocatalyst.Effects of initi... Photocatalytic oxidation kinetics of thiophene in n-octane/water extraction system was studied with fluorine and ferric ion codoped nano-TiO_2(nano-F^-/Fe^(3+)/TiO_2) powders used as the photocatalyst.Effects of initial concentration of thiophene and additional dosage of F^-/Fe^(3+)/TiO_2 on the reaction rate constant and half-life were investigated.The results showed that the appropriately added dosage of F^-/Fe^(3+)/TiO_2 was 0.1 g in the 100-mL reaction system and the photooxidative kinetics of thiophene in the presence of F^-/Fe^(3+)/TiO_2 catalyst was of first-order with a rate constant of 0.6508 h^(-1) and a half-life of 1.0651 h.The desulfurization rate of thiophene was 98.1%in 5 h and the sulfur content could be reduced from 800 ppm to 15 ppm.The reaction rate constant increased with a decreasing initial concentration of thiophene. 展开更多
关键词 DESULFURIZATION thiophene nano-F^-/Fe^(3+)/TiO_2 photocatalytic oxidation kinetics
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一种高速2-D滑动FFT的设计实现
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作者 许丁鸿 张多利 +2 位作者 陶相颖 韩帅鹏 宋宇鲲 《合肥工业大学学报(自然科学版)》 CAS 北大核心 2023年第7期912-918,共7页
文章介绍了采用2-D快速傅里叶变换(fast Fourier transform,FFT)算法的滑动窗FFT的基本特性原理和硬件实现过程,完成了窗长256点、步长16点的2-D滑动窗FFT的专用集成电路(application specific integrated circuit,ASIC)设计。传统FFT... 文章介绍了采用2-D快速傅里叶变换(fast Fourier transform,FFT)算法的滑动窗FFT的基本特性原理和硬件实现过程,完成了窗长256点、步长16点的2-D滑动窗FFT的专用集成电路(application specific integrated circuit,ASIC)设计。传统FFT算法受序列完整性的制约,时滞较大,无法满足某些高实时性信号分析领域的处理速度要求。该文采用滑动FFT算法,克服了传统FFT对序列完整性的依赖,设计的滑动FFT处理器使用2-D FFT压缩新序列计算时间,以基16蝶形运算器为核心,采用系数复用和高基Booth方法优化系数编码技术压缩乘法器的数量,减少电路面积。所设计的2-D滑动FFT完成单次滑动窗长的计算时间比传统算法节约了16.1%,变换结果与MATLAB的运算结果相比,信噪比(signal-to-noise ratio,SNR)大于130 dB。在TSMC 28 nm的工艺下,工作主频为600 MHz,面积为1980μm×2060μm。 展开更多
关键词 快速傅里叶变换(FFT) 滑动FFT 2-d FFT算法 高基Booth编码
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2-D distributed pose estimation of multi-agent systems using bearing measurements
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作者 Xu Fang Jitao Li +1 位作者 Xiaolei Li Lihua Xie 《Journal of Automation and Intelligence》 2023年第2期70-78,共9页
This article studies distributed pose(orientation and position)estimation of leader–follower multi-agent systems over𝜅-layer graphs in 2-D plane.Only the leaders have access to their orientations and position... This article studies distributed pose(orientation and position)estimation of leader–follower multi-agent systems over𝜅-layer graphs in 2-D plane.Only the leaders have access to their orientations and positions,while the followers can measure the relative bearings or(angular and linear)velocities in their unknown local coordinate frames.For the orientation estimation,the local relative bearings are used to obtain the relative orientations among the agents,based on which a distributed orientation estimation algorithm is proposed for each follower to estimate its orientation.For the position estimation,the local relative bearings are used to obtain the position constraints among the agents,and a distributed position estimation algorithm is proposed for each follower to estimate its position by solving its position constraints.Both the orientation and position estimation errors converge to zero asymptotically.A simulation example is given to verify the theoretical results. 展开更多
关键词 Pose estimation Distributed algorithm Bearing measurements Multi-agent system Local coordinate frame 2-d plane
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具有执行器饱和的切换2-D系统事件触发控制
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作者 骆茂森 黄世沛 《计算机测量与控制》 2023年第7期112-121,共10页
针对具有执行器饱和的切换2-D连续离散系统,提出了一种基于多Lyapunov函数法的事件触发控制方案;为了减少通信资源浪费和执行器的损耗,提出了一种事件触发机制;该触发机制考虑了执行器饱和特性,只有当执行器未饱和,且满足事件触发条件时... 针对具有执行器饱和的切换2-D连续离散系统,提出了一种基于多Lyapunov函数法的事件触发控制方案;为了减少通信资源浪费和执行器的损耗,提出了一种事件触发机制;该触发机制考虑了执行器饱和特性,只有当执行器未饱和,且满足事件触发条件时,控制器才会更新;利用凸组合技术和多Lyapunov函数法,提出了一种状态依赖的切换信号与状态反馈控制器的设计方法,并对闭环系统的指数稳定性进行了分析,利用线性矩阵不等式技术导出了控制器增益矩阵存在的充分条件;利用Darboux方程的仿真算例验证了所提出的事件触发控制方案的有效性,仿真结果表明了在所设计的控制方案下,闭环系统的状态是指数收敛的,同时还能减少通信资源的浪费。 展开更多
关键词 2-d系统 切换系统 执行器饱和 指数稳定 事件触发控制
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“探究2,4-D对插枝生根的作用”实验中因变量的确定
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作者 王维 《生物学教学》 2023年第6期55-56,共2页
“探究2,4-D对插枝生根的作用”是浙科版高中生物学教材选择性必修1教材中的重要实验,实践中一些师生对该实验中的因变量常有疑惑,本文选择常见的碰碰香作为实验材料展开探究。发现2,4-D浓度在2.5×10-4—2.5×10-14g/L浓度范围... “探究2,4-D对插枝生根的作用”是浙科版高中生物学教材选择性必修1教材中的重要实验,实践中一些师生对该实验中的因变量常有疑惑,本文选择常见的碰碰香作为实验材料展开探究。发现2,4-D浓度在2.5×10-4—2.5×10-14g/L浓度范围内,对根的平均长度和根的总长度作用差异不明显,但是对根的数量有显著的差异。该探究可为师生提供一定的参考。 展开更多
关键词 因变量2 4-d 碰碰香 总根长 平均根长 生根数
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NOVEL RED LIGHT-EMITTING POLYMERS BASED ON 2,7-CARBAZOLE AND THIOPHENE DERIVATIVES
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作者 杨伟 曹镛 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第2期231-240,共10页
A series of conjugated copolymers derived from 9-ethylhexyl-2,7-carbazole(Cz)and 4,7-di(4-hexylthien-2-yl)- 2,1,3-benzothiadiazole(DHTBT)was synthesized by Suzuki polycondensation.The photo-and electro-luminescent pro... A series of conjugated copolymers derived from 9-ethylhexyl-2,7-carbazole(Cz)and 4,7-di(4-hexylthien-2-yl)- 2,1,3-benzothiadiazole(DHTBT)was synthesized by Suzuki polycondensation.The photo-and electro-luminescent properties of these polymers were investigated.Efficient energy transfer from the Cz segment to the DHTBT unit occurs even if the DHTBT content as low as 1 mol%.PL emission was red-shifted significantly from 645 nm to 700 nm with the increase in DHTBT content by 1-50 mol%.PL efficiencies decreased... 展开更多
关键词 2 7-Carbazole thiophene derivatives Red light-emitting polymer.
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Calculations and Sensitivity Analysis of Chlorine-,NO_(x)-,and Bromine-Depleting Cycles of Stratospheric Ozone
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作者 Ibraheem Alelmi Sen Nieh 《Journal of Environmental Science and Engineering(B)》 CAS 2024年第2期53-69,共17页
This paper presents an engineering system approach using a 2D model of conservation of mass to study the dynamics of ozone and concerned chemical species in the stratosphere.By considering all fourteen photolysis,ozon... This paper presents an engineering system approach using a 2D model of conservation of mass to study the dynamics of ozone and concerned chemical species in the stratosphere.By considering all fourteen photolysis,ozone-generating,and-depleting chemical reactions,the model calculated the transient,spatial changes of ozone under different physical-chemical-radiative conditions.Validation against the measured data demonstrated good accuracy,close match of our model with the observed ozone concentrations at both 20°S and 90°N locations.The deviation in the average concentration was less than 1% and in ozone profiles less than 17%.The impacts of various chlorine-(Cl),nitrogen oxides-(NO_(x)),and bromine-(Br)depleting cycles on ozone concentrations and distribution were investigated.The chlorine catalytic depleting cycle was found to exhibit the most significant impact on ozone dynamics,confirming the key role of chlorine in the problem of ozone depletion.Sensitivity analysis was conducted with levels of 25%,50%,100%,200%,and 400% of the baseline value.The combined cycles(Cl+NO_(x)+Br)showed the most significant influence on ozone behavior.The total ozone abundance above the South Pole could decrease by a small 3%,from 281 DU(Dubson Units)to 273 DU for the 25% level,or by a huge thinning of 60%to 114 DU for the 400% concentration level.When the level of chlorine gases increased beyond 200%,it would cause ozone depletion to a level of ozone hole(below 220 DU).The 2D Ozone Model presented in this paper demonstrates robustness,convenience,efficiency,and executability for analyzing complex ozone phenomena in the stratosphere. 展开更多
关键词 Ozone depletion 2-d model CHLORINE BROMINE nitrogen oxides sensitivity analysis total ozone abundance DU
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固体添加剂2-(噻吩-2-亚甲基)丙二腈的合成及其有机光伏性能
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作者 沈星星 罗丹 +4 位作者 何源 杨述 谢家平 侯文龙 韩璐 《河北科技师范学院学报》 CAS 2024年第2期59-65,共7页
为了提高有机光伏器件性能,合成了一种结构简单、成本低的固体添加剂2-(噻吩-2-亚甲基)丙二腈(SAT),并测试了其对非富勒烯有机太阳能电池性能的影响。测试结果显示,优化后的共混薄膜的紫外可见吸收光谱红移了14 nm,荧光强度显著降低。而... 为了提高有机光伏器件性能,合成了一种结构简单、成本低的固体添加剂2-(噻吩-2-亚甲基)丙二腈(SAT),并测试了其对非富勒烯有机太阳能电池性能的影响。测试结果显示,优化后的共混薄膜的紫外可见吸收光谱红移了14 nm,荧光强度显著降低。而且,薄膜的结晶度更高,形成的相分离形貌更加均匀,分子堆叠更加有序,有利于激子分离和电荷传输。与未使用SAT优化的器件相比,当SAT的质量浓度为5 mg/mL时,开路电压由0.85 V降低至0.83 V,短路电流由21.15 mA/cm^(2)提升至23.58 mA/cm^(2),填充因子由65.70%提升至71.17%,能量转换效率由11.89%提升至13.90%。 展开更多
关键词 有机太阳能电池 固体添加剂 2-(噻吩-2-亚甲基)丙二腈 光伏性能
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Synthesis and Crystal Structure of 2,5-Bis(morpholino)-3,4-bis(p-chlorophenyl)thiophene
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作者 曾润生 邹建平 +2 位作者 王香善 穆学军 陆忠娥 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第3期279-282,共4页
The title compound 2,5-bis(morpholino)-3,4-bis(p-chlorophenyl) thiophene 2 was obtained by the reaction of -thio-p-chlorobenzoyl thioformmorpholine 1 with trimethyl phosphite in refluxing xylene. The crystal is of tri... The title compound 2,5-bis(morpholino)-3,4-bis(p-chlorophenyl) thiophene 2 was obtained by the reaction of -thio-p-chlorobenzoyl thioformmorpholine 1 with trimethyl phosphite in refluxing xylene. The crystal is of triclinic, space group P?with unit cell constants: a = 6.0740(1), b = 10.3250(1), c = 19.779(2) , ?= 76.740(1), = 87.110(1), = 74.920(1), C24H24Cl2N2O2S, Mr = 475.41, Z = 2, V = 1165.7(3) ?, Dc = 1.354 g/cm3, (MoK) = 0.71073, = 0.392 mm-1, F(000) = 496, the final R = 0.0324 and wR = 0.0819 for 3102 observed reflections (I > 2(I)). X-ray analysis reveals that the two morpholinyl groups are located at the -position of thiophene, and the two p-chlorophenyl groups at the -position. Therefore, the title compound is a new symmetric thiophene derivative. 展开更多
关键词 X-ray crystallography 2 5-bis(morpholino)-3 4-bis(p-chlorophenyl) thiophene crystal structure
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2,4-D丁酯对轮叶马先蒿的防除效果及对草地植被的影响 被引量:12
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作者 张晓艳 胡玉昆 +2 位作者 姬承东 郭正刚 公延明 《草业学报》 CSCD 北大核心 2009年第4期168-174,共7页
为有效灭除草地害草轮叶马先蒿,采用2,4-D丁酯在巴音布鲁克高寒草地进行了不同时期不同剂量化学防除试验。结果表明,防除轮叶马先蒿的最佳时期为盛花期;最佳药品用量是0.066 mL/m2;喷施2,4-D丁酯后,草地植被生态环境得到明显改善,轮叶... 为有效灭除草地害草轮叶马先蒿,采用2,4-D丁酯在巴音布鲁克高寒草地进行了不同时期不同剂量化学防除试验。结果表明,防除轮叶马先蒿的最佳时期为盛花期;最佳药品用量是0.066 mL/m2;喷施2,4-D丁酯后,草地植被生态环境得到明显改善,轮叶马先蒿被部分或完全灭除,优良牧草垂穗披碱草在草地群落中占据优势地位,同时杂类草新疆假龙胆受到一定的抑制,草地质量明显提高。 展开更多
关键词 高寒草地 2 4-d丁酯 轮叶马先蒿 化学防除
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三乙基苄基氯化铵催化下水介质中吡喃并[2,3-d]嘧啶衍生物的一步合成 被引量:7
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作者 梁静 张梅梅 +2 位作者 魏贤勇 宗志敏 王香善 《有机化学》 SCIE CAS CSCD 北大核心 2007年第11期1420-1423,共4页
以芳亚甲基丙二腈、1,3-二甲基巴比妥酸为原料,以水为溶剂,在100℃以三乙基苄基氯化铵(TEBAC)为催化剂合成了一系列的吡喃并[2,3-d]嘧啶衍生物,该方法具有反应条件温和,产率良好(78%~90%)和环境友好等优点.产物的结构通过IR,1H NMR和... 以芳亚甲基丙二腈、1,3-二甲基巴比妥酸为原料,以水为溶剂,在100℃以三乙基苄基氯化铵(TEBAC)为催化剂合成了一系列的吡喃并[2,3-d]嘧啶衍生物,该方法具有反应条件温和,产率良好(78%~90%)和环境友好等优点.产物的结构通过IR,1H NMR和元素分析表征,并进一步通过X射线衍射分析确证. 展开更多
关键词 吡喃并[2 3-d]嘧啶 TEBAC 合成
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