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新型数字基础设施对碳生产率的影响——长江经济带例证

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长江流域资源与环境 2024年第9期33卷 1844-1859页

作者：陈志建申世敬程玉浩张庆娟华东交通大学经济管理学院江西南昌330013

在实现我国经济增长与碳减排双重目标下,新型数字基础设施为提升区域碳生产率提供了“新基遇”及切实可行的路径。为此,研究选择可获取的2009~2019年长江经济带108个城市的最新面板数据,通过核密度估计模型、空间杜宾模型、中介效应模... 详细信息

在实现我国经济增长与碳减排双重目标下,新型数字基础设施为提升区域碳生产率提供了“新基遇”及切实可行的路径。为此,研究选择可获取的2009~2019年长江经济带108个城市的最新面板数据,通过核密度估计模型、空间杜宾模型、中介效应模型等方法探讨新型数字基础设施与碳生产率空间演化态势,并进一步分析新型数字基础设施对碳生产率的影响及传导机制。结果表明:(1)长江经济带新型数字基础设施发展水平与碳生产率水平均呈现空间分异特征,同时两者之间存在空间错位的演化态势。(2)新型数字基础设施显著提高了碳生产率,且这一结论在一系列稳健性检验后仍然成立。(3)绿色技术创新在新型数字基础设施与碳生产率的正向关系中具有中介传导作用;新型数字基础设施对碳生产率的作用存在空间溢出效应。(4)进一步异质性分析发现,非资源型城市新型数字基础设施的发展对碳生产率的提升作用较强,成渝城市群受新型数字基础设施发展的影响更大。研究结论为推动我国实现“双碳”目标,促进城市高质量发展提供了新的经验证据。

关键词：新型数字基础设施碳生产率绿色技术创新空间杜宾模型城市群

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柱花草SgALMT1基因克隆与表达分析

草地学报 2024年第4期32卷 1078-1086页

作者：缪野刘怀锦刘莉婷罗丽娟陈志坚海南大学热带农林学院海南海口570228 中国热带农业科学院热带作物品种资源研究所/农业农村部华南作物基因资源与种质创制重点实验室海南海口571101 热带作物生物育种全国重点实验室海南三亚572024

为探索铝激活苹果酸转运蛋白(Aluminum-activated malate transporter,ALMT)在植物适应酸性土壤铝毒害中的重要作用,本研究以柱花草(Stylosanthes guianensis)为研究材料,克隆了柱花草SgALMT1基因,并进行了生物信息学、亚细胞定位及基... 详细信息

为探索铝激活苹果酸转运蛋白(Aluminum-activated malate transporter,ALMT)在植物适应酸性土壤铝毒害中的重要作用,本研究以柱花草(Stylosanthes guianensis)为研究材料,克隆了柱花草SgALMT1基因,并进行了生物信息学、亚细胞定位及基因表达分析。结果表明:SgALMT1基因全长为1350 bp,编码450个氨基酸残基,蛋白分子量为50.6 kDa,包含6个跨膜结构域;亚细胞定位分析表明,SgALMT1蛋白定位在拟南芥原生质体细胞膜上,为膜蛋白。定量PCR结果表明,SgALMT1基因在柱花草叶中的表达量高于根中的表达量;铝处理增强了SgALMT1基因在柱花草根中的表达,表明SgALMT1基因可能参与了柱花草应对铝胁迫;另外,缺氮处理增强了SgALMT1基因在柱花草叶中的表达,而缺磷处理增强了SgALMT1在根中的表达。本研究结果为解析柱花草响应铝毒害和养分缺乏的机理提供了候选基因资源。

关键词：柱花草铝毒害基因表达苹果酸亚细胞定位

2.7-4.0 GHz PLL with dual-mode auto frequency calibration for navigation system on chip

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Journal of Central South University 2016年第9期23卷 2242-2253页

作者： chen zhi-jian CAI Min HE Xiao-yong XU Ken School of Electronic and Information Engineering South China University of Technology Guangzhou 510640 China

A 2.7-4.0 GHz dual-mode auto frequency calibration(AFC) fast locking PLL was designed for navigation system on chip(SoC). The SoC was composed of one radio frequency(RF) receiver, one baseband and several system control parts. In the proposed AFC block, both analog and digital modes were designed to complete the AFC process. In analog mode, the analog part sampled and detected the charge pump output tuning voltage, which would give the indicator to digital part to adjust the voltage control oscillator(VCO) capacitor bank. In digital mode, the digital part counted the phase lock loop(PLL) divided clock to judge whether VCO frequency was fast or slow. The analog and digital modes completed the auto frequency calibration function independently by internal switch. By designing a special switching algorithm, the switch of the digital and analog mode could be realized anytime during the lock and unlock detecting process for faster and more stable locking. This chip is fabricated in 0.13 μm RF complementary metal oxide semiconductor(CMOS) process, and the VCO supports the frequency range from 2.7 to 4.0 GHz. Tested 3.96 GHz frequency phase noise is -90 d Bc/Hz@100 k Hz frequency offset and -120 d Bc/Hz@1 MHz frequency offset. By using the analog mode in lock detection and digital mode in unlock detection, tested AFC time is less than 9 μs and the total PLL lock time is less than 19 μs. The SoC acquisition and tracking sensitivity are about-142 d Bm and-155 d Bm, respectively. The area of the proposed PLL is 0.35 mm^2 and the total SoC area is about 9.6 mm^2.

关键词： auto frequency calibration phase lock loop voltage control oscillator lock time

Electro-optic and Photorefractive Properties of Doped Poly (N-Vinylcarbazole)

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Chinese Physics Letters 1997年第6期14卷 474-477页

作者： WANG Shu-feng HUANG zhi-wen chen zhi-jian GONG Qi-huang ZHANG zhi-jie chen Hui-ying Department of Physics Mesoscopic Physics LaboratoryPeking UniversityBeijing 100871 Department of Chemistry Peking UniversityBeijing 100871

In this work,100μm-thick doped poly(N-vinylcarbazole)films with different contents of the electro-optic(EO)chromophore 2,5-dimethyl-4-(p-nitrophenylazo)anisole and plasticizer N-ethylcarbazole were prepared and sandwiched between two indium-tin oxide-covered glass *** EO measurements and two-beam-coupling experiments were performed by using a single mode(TEM00)He-Ne *** the EO coefficient and the gain for two-beam-coupling were found to be strongly depending on the content of plasticizer.

关键词： Photorefractive coupling beam

Photorefractive Effect in Poly (N-Vinylcarbazole) Composite with Fullerene

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Chinese Physics Letters 1997年第11期14卷 842-844页

作者： chen zhi-jian XU Li-fang HUANG zhi-wen GONG Qi-huang ZHANG zhi-jie chen Yi-wang chen Hui-ying Department of Physics Mesoscope Physics LaboratoryPeking UniversityBeijing 100871 Department of Chemistry Peking UniversityBeijing 100871

The photorefractive effect was observed in poly(N-vinylcarbazole)composite films doped with electro-optic chromophore 2,5-dimetly-4(p-nitrophenylazo)anisole,plasticizer N-ethylcarbazole and different content fullerene *** two-beam coupling experiment was performed by using a cw He-Ne laser at *** two-beam-coupling gain coefficient as higher as 140cm^(-1) was measured at poling dc electric field of 76V/μm and it was also found to be relied on the content of photosensitizer C60.

关键词： carbazole coupling content

Response Time Characteristics and Holographic Gratings in an Azo-Dye Doped Photorefractive Polymeric Composite

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Chinese Physics Letters 1998年第5期15卷 351-353页

作者： WANG Feng chen zhi-jian GONG Qi-huang chen Yi-wang chen Hui-ying Department of Physics Mesoscopic Physics LaboratoryPeking UniversityBeijing 100871 Department of Chemistry Peking UniversityBeijing 100871

Theoretical and experimental investigation on the applied electric field-and intensity-dependent photorefractive response in a photorefractive polymeric composite is *** decay time constant and the corresponding grating-amplitude for the composite consisting of 1-n-butoxy1-2,5-dimethy1-4-(4’-nitrophenylazo)benzene:poly(N-vinylcarbazole):2,4,7-trinitro-9-fluorenone with a weight ratio 44:55:1 were *** results revealed that there existed two gratings simultaneously,one was caused by the photorefractive effect,and the other was contributed from the photo-isomerization *** dynamic process for the photorefractive grating was explained with a modified band transport model.

关键词： Photorefractive composite grating

Modified-PVK-based Photorefractive Three-Component Low-T_(g) Composites

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Chinese Physics Letters 1999年第5期16卷 353-355页

Two modified poly(N-carbazole),poly(2-carbazolylethyl methacrylate)(PCEMA)and poly(3-carbazolylpropyl methacrylate)(PCPMA),were *** with electro-optic(EO)chromophore 1-n-butoxyl-2,5-dimethyl-4-(4'-nitrophenylazo)benzene and the photosensitizer 2,4,7-trinitro-9-fluorenone,the EO response and photore-fractive(PR)effect were studied *** to the shorter spacer between the carbazolyl and the main-chain and thus a higher glass-transition-temperature T_(g),PCEMA-based composite exhibited an effective EO coefficient as only a quarter as that in PCPMA-based ***,a slight higher two-beam coupling coefficient and much faster PR response were observed in the *** was suggested that both the spacer length and the polymerization degree changed the T_(g) and the number density of traps,which decided the EO and PR responses.

关键词： coefficient faster shorter

Image Storage and Real-Time Distorted Image Correction by Using Photorefractivity in a Stable Photorefractive Polymer Composite

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Chinese Physics Letters 1999年第6期16卷 420-422页

Using a highly stable and excellently performed three-component photorefractive(PR)polymer composite,poly(N-vinylcarbazole):1-n-butoxyl-2,5-dimethyl-4-(4-nitrophenylazo)benzene:2,4,7-tnnitro-9-fluorenone,optical image storage was *** dark storage time was *** PR response time was measured to be about 200 ms at an intensity of 1 W/cm^(2) with an applied electric Held of 84 V/μm.A proof-of-principle experiment on real-time correction of distorted images based on phase conjugation of four-wave mixing geometry was also carried out.

关键词： composite Image correction

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压电致动器非线性特征的控制策略研究进展

广东工业大学学报 2024年第4期41卷 14-25页

作者：施建昌肖晓兰李昊冯发辉陈志健区森荣陈可广东工业大学机电工程学院广东广州510006 广东工业大学高性能工具全国重点实验室广东广州510006 利物浦大学电气与电子工程学院利物浦L693GJ

压电致动器具有位移分辨率高、体积小、响应快、驱动负载能力强、可多自由度输出以及不受电磁干扰等优点,被广泛应用在微纳加工、微机电系统封装、生物医学以及航空航天等领域。然而,由于压电致动器自身存在的迟滞、蠕变等非线性特征,... 详细信息

压电致动器具有位移分辨率高、体积小、响应快、驱动负载能力强、可多自由度输出以及不受电磁干扰等优点,被广泛应用在微纳加工、微机电系统封装、生物医学以及航空航天等领域。然而,由于压电致动器自身存在的迟滞、蠕变等非线性特征,使得输出的稳定性以及精确度受到一定的影响,需采取恰当的控制策略解决上述问题。本文首先对压电致动器的非线性特征进行概述;其次,重点回顾了迟滞模型和蠕变模型的发展历程;然后,介绍了压电致动器的控制补偿策略及研究进展;最后对压电致动器控制技术的未来发展方向进行了讨论与展望。

关键词：压电致动器非线性特征迟滞模型蠕变模型控制策略