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数字基础设施、要素配置效率与现代化产业体系建设

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统计与决策 2024年第9期40卷 118-123页

作者：杨伟涛汪慧郑州大学哲学学院郑州450001 郑州大学马克思主义学院郑州450001

现代化产业体系作为现代化经济体系的核心组成,是建设社会主义强国的重要物质支撑,亦是推进中国式现代化,实现第二个百年奋斗目标的坚实基础。文章基于2010-2022年中国30个省份的面板数据,实证检验数字基础设施对现代化产业体系建设的... 详细信息

现代化产业体系作为现代化经济体系的核心组成,是建设社会主义强国的重要物质支撑,亦是推进中国式现代化,实现第二个百年奋斗目标的坚实基础。文章基于2010-2022年中国30个省份的面板数据,实证检验数字基础设施对现代化产业体系建设的影响。结果表明:数字基础设施对现代化产业体系建设具有显著促进作用,且在经过一系列检验后,该结论依旧成立;要素配置效率在二者关系中发挥正向调节作用;在金融发展水平约束下,数字基础设施对现代化产业体系建设的影响呈现非线性特征;数字基础设施对东部地区现代化产业体系建设的促进效果更强,对东北地区现代化产业体系建设的促进效果不显著。

关键词：数字基础设施现代化产业体系要素配置效率金融发展

Single event effects evaluation on convolution neural network in Xilinx 28 nm system on chip

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Chinese Physics B 2024年第7期33卷 638-644页

作者：赵旭杜雪成熊旭马超杨卫涛郑波周超 School of Nuclear Science and Technology University of South ChinaHengyang 421001China School of Microelectronics Xidian UniversityXi'an 710071China

Convolutional neural networks(CNNs) exhibit excellent performance in the areas of image recognition and object detection, which can enhance the intelligence level of spacecraft. However, in aerospace, energetic particles, such as heavy ions, protons, and alpha particles, can induce single event effects(SEEs) that lead CNNs to malfunction and can significantly impact the reliability of a CNN system. In this paper, the MNIST CNN system was constructed based on a 28 nm systemon-chip(SoC), and then an alpha particle irradiation experiment and fault injection were applied to evaluate the SEE of the CNN system. Various types of soft errors in the CNN system have been detected, and the SEE cross sections have been calculated. Furthermore, the mechanisms behind some soft errors have been explained. This research will provide technical support for the design of radiation-resistant artificial intelligence chips.

关键词： single event effects convolutional neural networks alpha particle system on chip fault injection

Scaling correction approaches for reducing delocalization error in density functional approximations

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Science China Chemistry 2015年第12期58卷 1825-1844页

作者： Xiao Zheng Chen Li Dadi Zhang weitao yang Synergetic Innovation Center of Quantum Information and Quantum Physics & Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemistry Duke University Key Laboratory of Theoretical Chemistry of Environment

Delocalization error associated with the presently used density functional approximations is one of the main sources of errors which plague density functional theory calculations. In this paper, we give a comprehensive review on scaling correction(SC) approaches developed recently for reducing the delocalization error. The global and local SC approaches impose the rigorous Perdew-Parr-Levy-Balduz condition that the total electronic energy should scale linearly between integer electron numbers, on systems involving global and local fractional electron distributions, respectively. After presenting the theoretical background and mathematical formulation of scaling corrections, we demonstrate that they lead to universal alleviation of delocalization error. This is exemplified by the substantial improvement for the prediction of a wide range of electronic properties, including Kohn-Sham frontier orbital energies and band gaps, dissociation behavior of molecules, reaction barriers, electric polarizabilities, and charge-transfer species. The encouraging performances of SC approaches highlight their practicality and usefulness, and also affirm that an explicit treatment of fractional electron distributions is essentially important for reducing the intrinsic delocalization error. The existing limitations, the remaining challenges, and the future perspectives of SC are also discussed. Moreover, the SC approaches are compared with some existing methods attempting to remove the self-interaction error, such as the Perdew-Zunger self-interaction correction, the local hybrid hyper-generalized gradient approximations, and the rangeseparated density functional approximations. The unique advantages of SC suggest that it could open a novel and potentially paradigm-changing route for advancing density functional theory methods towards chemical accuracy.

关键词： density functional theory scaling correction approach exchange-correlation functional density functional approximations

Kinetics of water–isocyanate reaction in N,N-dimethylformamide

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Chinese Journal of Chemical Engineering 2017年第10期25卷 1435-1441页

作者： Zhirong Chen weitao yang Hong Yin Shenfeng Yuan College of Chemical and Biologlical Engineering Zhejiang University Hangzhou 310027 China

The uncatalyzed reaction of p-tolyl isocyanate(p-TI)with water in N,N-dimethylformamide(DMF)was investigated by high performance liquid chromatography(HPLC).The reactions were carried out at different temperatures from 293 K to 323 K,using various molar ratios of water to p-TI.DMF,as a special amide,was proved to be an efficient catalyst for water–isocyanate reaction.Under the reaction conditions in this study,substituted urea was the only final product observed.An appreciable amount of intermediate p-toluidine was detected.Concentrations of the isocyanate group as well as the amine and urea were determined as a function of time.New kinetic equations were deduced for each of the substance on the basis of a multistep mechanism,instead of a simple second order reaction as usual.Kinetic constants were calculated using the software MATLAB.Furthermore,the effects of temperature and concentrations of reactants on the reaction rate and amine content were discussed.The activation energy of each step was also determined.

关键词： N-二甲基甲酰胺甲苯异氰酸酯反应动力学高效液相色谱法反应物浓度水异氰酸酯基团 MATLAB

Localized orbital scaling correction for systematic elimination of delocalization error in density functional approximations

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National Science Review 2018年第2期5卷 203-215页

作者： Chen Li Xiao Zheng Neil Qiang Su weitao yang Department of Chemistry Duke University Synergetic Innovation Center of Quantum Information and Quantum Physics Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China CAS Center for Excellence in Nanoscience University of Science and Technology of China Department of Physics Duke University Key Laboratory of Theoretical Chemistry of Environment School of Chemistry and EnvironmentSouth China Normal University

The delocalization error of popular density functional approximations(DFAs) leads to diversified problems in present-day density functional theory calculations. For achieving a universal elimination of delocalization error, we develop a localized orbital scaling correction(LOSC) framework, which unifies our previously proposed global and local scaling approaches. The LOSC framework accurately characterizes the distributions of global and local fractional electrons, and is thus capable of correcting system energy, energy derivative and electron density in a self-consistent and size-consistent manner. The LOSC–DFAs lead to systematically improved results, including the dissociation of cationic species, the band gaps of molecules and polymer chains, the energy and density changes upon electron addition and removal, and photoemission spectra.

关键词： localized orbital scaling correction delocalization error density functional approximation localized frontier orbital local fraction orbitalet

Black phosphorus nanoflakes as morphology modifier for efficient fullerene-free organic solar cells with high fill-factor and better morphological stability

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Nano Research 2019年第4期12卷 777-783页

作者： weitao yang Long Ye Fenfa Yao Chuanhong Jin Harald Ade Hongzheng Chen State Key Laboratory of Silicon Materials MOE Key Laboratory of Macromolecular Synthesis and Functionalization& Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China Department of Physics Organic and Carbon Electronics Laboratory (ORaCEL) North Carolina State University Raleigh NC 27695 USA State Key Laboratory of Silicon Materials School of Materials Science and Engineering Zhejiang University Hangzhou 310027 China

Morphology of the donor:acceptor blend plays a critical role in the photovoltaic performance of the organic solar cells (OSCs).Herein,liquid-phase-exfoliated black phosphorus nanoflakes (BPNFs),for their outstanding electronic property and good compatibility to solution process,were applied to fullerene-free OSCs as morphology modifier.Revealed by X-ray scattering measurements,the PTB7-Th:IEICO-4F blends incorporated with BPNFs exhibit more ordered π-π stacking and promoted domain purity,contributing to lower charge transport resistance and suppressed charge recombination within the bulk heterojunction (BHJ).As a result,a high fill factor (FF) of 0.73 and a best power conversion efficiency (PCE) of 12.2% were obtained for fullerene-free OSCs based on PTB7-Th:IEICO-4F blends incorporating with BPNFs,which is among the highest FF of the as-cast fullerene-free OSCs with PCE over 12%.More importantly,the embedded BPNFs help to improve the morphological stability of the devices probably by retarding the phase mixing in the BHJ during the aging period.Besides,analogous enhancements were observed in another fullerene-free OSCs based on PBDB-T:ITIC.In a word,this work provides a new strategy of using two-dimentional nanoflakes as facile and universal morphology modifier for efficient fullerene-free OSCs.

关键词： fullerene-free organic solar cells black phosphorus nanoflakes morphology tuning device stability

基于Airpak的幼儿园生活单元空气质量模拟分析

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制冷 2024年第2期43卷 60-64页

作者：杨伟涛筑博设计股份有限公司广东深圳518042

通过对幼儿园生活单元建立物理数学模型,基于Airpak模拟分析了排风量、新风量、新风口位置以及室外风速对室内空气品质的影响。结果表明,门窗关闭的室内,仅设置排风并不能有效降低室内CO_(2)平均浓度;引入新风对降低室内CO_(2)平均浓度... 详细信息

通过对幼儿园生活单元建立物理数学模型,基于Airpak模拟分析了排风量、新风量、新风口位置以及室外风速对室内空气品质的影响。结果表明,门窗关闭的室内,仅设置排风并不能有效降低室内CO_(2)平均浓度;引入新风对降低室内CO_(2)平均浓度效果显著;新风口距离人员越近,并非越有利于降低室内CO_(2)平均浓度;过渡季节,开启门窗室内CO_(2)平均浓度水平明显降低。

关键词：空气品质室内CO_(2)平均浓度新风

Highly efficient and thermal stable guanidinium-based two-dimensional perovskite solar cells via partial substitution with hydrophobic ammonium

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Science China Chemistry 2019年第7期62卷 859-865页

作者： Yingzhu Zhang Jiehuan Chen Xiaomei Lian weitao yang Jun Li Shuoxun Tian Gang Wu Hongzheng Chen State Key Laboratory of Silicon Materials Key Laboratory of Macromolecular Synthesis and Functionalization (Ministry of Education)Department of Polymer Science and Engineering Zhejiang University

Layered two-dimensional(2D)perovskite solar cells(PVSCs)with a chemical formula of C(NH2)3(CH3NH3)3Pb3I10(n=3)have been fabricated through additive engineering,wherein stoichiometrically equivalent guanidinium(GA+)and methylammonium(MA+)serve as spacer cations.The crystallinity of the perovskite films is dramatically enhanced with proper amount of methylammonium thiocyanate(MASCN)added into the precursor solution.In addition,we substitute a small amount of MA+with hydrophobic phenylethylammonium(PEA+),which can passivate trap states of the perovskite films.As a result,the open circuit voltage increases to 1.1 V and the best power conversion efficiency(PCE)of 10.12%is yielded.Furthermore,superior thermal stability and balanced moisture stability of the PEA-substituted GA-based PVSCs are demonstrated,compared to the popular 3D MAPbI3and 2D PEA-based PVSCs.They retain approximately 80%of the original PCE after 30 d at 20%relative humidity(RH),and 50%of the original PCE after 3200 min at 85°C without any encapsulation.This work suggests a new route to achieve both heat and humidity stable PVSCs by simply mixing different spacer cations.

关键词： guanidinium-based 2D perovskite solar cells additive engineering PEA substitution stability

Donor-acceptor(D-A)terpolymers based on alkyl-DPP and t-BocDPP moieties for polymer solar cells

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Chinese Chemical Letters 2017年第12期28卷 2223-2226页

作者： Fateh Ullah Sun Qian weitao yang Muhammad Naeem Shah Zhongqiang Zhang Hongzheng Chen Chang-Zhi Li MOE Key Laboratory of Macromolecular Synthesis and Functionalization State Key Laboratory of Silicon MaterialsDepartment of Polymer Science andEngineeringZhejiang UniversityHangzhou 310027China

A series of low band gap terpolymers based on 4,8-bis（5-（2-ethylhexyl）thiophen-2-yl）benzo[l,2-b：4,5- b＇]dithiophene （BDTr） and diketopyrrolopyrrole （DPP） with varied solubilizing groups （i.e., tert- butoxycarbonyl, t-Boc and 2-octyldodecyl） are developed as electron donors for bulk heterojunction （BHJ） polymer solar cells （PSCs）. The results reveal that the one with 50% t-Boc concentration （P3） performs better than the other terpolymers used in this study in conventional PSC devices with a power conversion efficiency of 2.92%.

关键词： Conjugated polymerOrganic semiconductorPolymer solar cellsBulk heterojunctionDiketopyrrolopyrrole