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Polypyrrole-based hybrid nanostructures grown on textile for wearable supercapacitors

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Nano Research 2019年第5期12卷 1129-1137页

作者： Lingchang Wang chenguang zhang Xin Jiao Zhihao Yuan School of Materials Science and Engineering Tianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory for Photoelectric Materials & Devices Tianjin University of TechnologyTianjin 300384China Key Laboratory of Display Materials and Photoelectric Devices Ministry of EducationTianjin University of TechnologyTianjin 300384China

In the development of wearable energy devices,polypyrrole (PPy) is considered as a promising electrode material owing to its high capacitance and good mechanical ***,we report a PPy-based hybrid structure consisting of vertical PPy nanotube arrays and carbon nano-onions (CNOs) grown on textile for wearable *** this hybrid nanostructure,the vertical PPy nanotubes provide straight and superhighways for electron and ion transport,boosting the energy storage;while the CNOs mainly act as a conductivity retainer for the underlayered PPy film during stretching.A facile template-degrading method is developed for the large-area growth of the PPy-based hybrid nanostructures on the textile through one-step polymerization *** fabricated stretchable supercapacitor exhibits superior energy storage capacitance with the specific capacitance of 64 F·g^-***,it presents the high capacitance retention of 99% at a strain of 50% after 500 stretching ***,we demonstrate that the textile-based stretchable supercapacitor device can provide a stable energy storage performance in different wearable situations for practical *** use of the PPy-based hybrid nanostructures as the supercapacitor electrode offers a novel structure design and a promising opportunity for wearable power supply in real applications.

关键词： wearable supercapacitor polypyrrole nanotube carbon nano-onion template-degrading method stretchable electrode

A metric normalization of tree edit distance

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Frontiers of Computer Science 2011年第1期5卷 119-125页

作者： Yujian Li (1) liyujian@*** zhang chenguang (12) Beijing Univ Technol Coll Comp Sci & Technol Beijing 100124 Peoples R China Hainan Univ Coll Informat Sci & Technol Haikou 570228 Peoples R China

Traditional normalized tree edit distances do not satisfy the triangle inequality. We present a metric normalization method for tree edit distance, which results in a new normalized tree edit distance fulfilling the triangle inequality, under the condition that the weight function is a metric over the set of elementary edit operations with all costs of insertions/deletions having the same weight. We prove that the new distance, in the range [0, 1], is a genuine metric as a simple function of the sizes of two ordered labeled trees and the tree edit distance between them, which can be directly computed through tree edit distance with the same complexity. Based on an efficient algorithm to represent digits as ordered labeled trees, we show that the normalized tree edit metric can provide slightly better results than other existing methods in handwritten digit recognition experiments using the approximating and eliminating search algorithm （AESA） algorithm.

关键词： metric normalization tree edit distance,triangle inequality approximating and eliminating searchalgorithm (AESA)

Graphene quantum dots derived from hollow carbon nano-onions

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Nano Research 2018年第1期11卷 174-184页

作者： chenguang zhang Jiajun LI Xianshun Zeng Zhihao Yuan Naiqin Zhao [1School of Materials Science and Engineering Tianjin University of Technology Tianjin 300384 China [2School of Materials Science and Engineering Tianin University Tianin 300072 China [3Tianjin Key Lab for Photoelectric Materials & Devices Tianjin 300384 China [4Collaborative Innovation Center of Chemical Science and Engineering Tianjin University Tianjin 300072 China

Herein, carbon nano-onions （CNOs） with different structures have been investigated as precursors for the synthesis of graphene quantum dots （GQDs）. It was found that hollow CNOs yield GQDs with a uniform size distribution, whereas metal encapsulation in the CNO structure is disadvantageous for the same. Furthermore, the hollow CNOs are also advantageous for the synthesis of GQDs with a yellow-green hybrid luminescence and long-ranged excitation wavelength （λex）-independent photoluminescent （PL） behavior, in which the λex upper limit was 480 nm. These features enable safe sensing and cell tracking applications with a longer excitation wavelength in the visible light region. The potential applications of the synthesized GQDs as fluorescent sensing probes for detecting Cu（II） ions and non-toxic cell imaging under visible light excitation have been demonstrated. This means that sensing and bioimaging can be accomplished in the natural environment with no need for UV excitation. This work provides a reference to researchers in tailoring CNO structures in terms of their inner space to synthesize GQDs with the desired luminescence behavior.

关键词： graphene quantum dots carbon nano-onions fluorescent quenching bioimaging

Experimental and numerical simulation of bird-strike performance of lattice-material-infilled curved plate

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Chinese Journal of Aeronautics 2021年第8期34卷 245-257页

作者： Jun YAN chenguang zhang Sixu HUO Xianghai CHAI Zhihui LIU Kun YAN State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsDalian University of TechnologyDalian 116024China Ningbo Institute of Dalian University of Technology Ningbo 315016China Department of Discipline Engineering AVIC Commercial Aircraft Engine Co.LTDShanghai 200241China Shanghai Engineering Research Center of Civil Aero Engine Shanghai 200241China School of Chemical Engineering Dalian University of TechnologyDalianLiaoning 116024China

The anti-bird-strike performance of a lattice-material-infilled curved plate is investigated *** automatically filling the curved structure by classical lattice material filling methods will cause a large number of manufacturing defects,a space-dependent lattice material filling method for the curved plate is firstly proposed in this paper Next,using a face-centered cubic lattice,a lattice-material-infilled test piece with a hollow ratio of 40.8%is *** test pieces are manufactured via additive manufacturing using titanium *** bird-strike experimental tests,the test pieces are crashed against gelatin birds at an impact velocity of 200 m/*** strain gauges are used to record the crash history and the results are ***,a numerical analysis to simulate the bird-strike experiment is *** results from the experimental tests and numerical simulation agree *** work shows that the lattice-material-infilled curved plate yields promising bird-strike ***,lattice-infilled materials are feasible for protecting aerospace components against bird-strike as well as for reducing the component weight.

关键词： Bird-strike test Face-centered cubic lattice Infilled curved plate Lattice material Numerical simulation

Compound Formula Rehmannia alleviates levodopainduced dyskinesia in Parkinson's disease

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Neural Regeneration Research 2014年第4期9卷 407-412页

作者： Long Teng Fang Hong chenguang zhang Jiancheng He Haiying Wang Shanghai University of Traditional Chinese Medicine

Compound Formula Rehmannia has been shown to be clinically effective in treating Parkinson＇s disease and levodopa-induced dyskinesia; however, the mechanisms remain unclear. In this study, we established a model of Parkinson＇s disease dyskinesia in rats, and treated these animals with Compound Formula Rehmannia. Compound Formula Rehmannia inhibited the increase in mRNA expression of N-methyl-D-aspartate receptor subunits 1 and 2 and excitatory amino acid neurotransmitter genes, and it inhibited the reduction in expression of γ-aminobutyric acid receptor B1, an inhibitory amino acid neurotransmitter gene, in the corpus striatum. In addition, Compound Formula Rehmannia alleviated dyskinesia symptoms in the Parkinson＇s disease rats. These experimental findings indicate that Compound Formula Rehmannia alleviates levodopa-induced dyskinesia in Parkinson＇s disease by modulating neurotransmitter signaling in the corpus striatum.

关键词： nerve regeneration traditional Chinese medicine Parkinson's disease dyskinesia excitato-ry amino acid inhibitory amino acid neurobehavior Compound Formula Rehmannia NSFC grant neural regeneration

Self-anchored catalysts for substrate-free synthesis of metal-encapsulated carbon nano-onions and study of their magnetic properties

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Nano Research 2016年第4期9卷 1159-1172页

作者： chenguang zhang Jiajun Li Chunsheng Shi Chunnian He Enzuo Liu Naiqin Zhao School of Materials Science and Engineering Tianjin University Tianjin 300072 China Collaborative Innovation Center of Chemical Science and Engineering Tianjin University Tianjin 300072 China

We demonstrate the synthesis of a novel self-anchored catalyst structure containing a Fe-Ni alloy nanosheet generated by phase separation for the substrate-free synthesis of carbon nanostructures. Fast Fourier transform analysis was carried out in order to investigate both the phase and structural evolution of the alloy nanosheet during reduction and chemical vapor deposition （CVD） growth. y-Fe-Ni （Feo.64Nio.36） and a-Fe-Ni （kamacite） phases were formed and separated on the NiFe204 nanosheet catalyst precursor during H2 reduction, forming selfanchored mono-dispersed y-Fe-Ni nanocrystals on a a-Fe-Ni matrix. The Fe-Ni alloy nanosheet serves both as a catalyst for growing metal-encapsulated carbon nano-onions （CNOs）, and as a support for anchoring these preformed nano- particles, yielding mono-dispersed catalyst nanoparticles with no requirement of additional substrates for the CVD growth. This synthesis is capable of mitigating the coalescence and Ostwald ripening without the assistance of an additional substrate. This structure allows for the growth of uniform-sized CNOs despite the aggregation, crumbling, and stacking of the alloy sheet. This study provides a promising design for novel catalyst structures by phase separation towards the substrate-free synthesis of carbon nanostructures in large scale. Finally, the ferromagnetic Feo.64Ni0.36@#CNOs particles demonstrate their application in both magnetic storage and water purification, as a non-toxic water treatment material.

关键词： carbon nano-onion self-anchored catalyst phase separation y-Fe-Ni a-Fe-Ni chemical vapor deposition

Dietary fat and carbohydrate-balancing the lactation performance and methane emissions in the dairy cow industry: A meta-analysis

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Animal Nutrition 2024年第2期17卷 347-357页

作者： chenguang zhang Xingwei Jiang Shengru Wu Jun zhang Yue Wang Zongjun Li Junhu Yao College of Animal Science and Technology Northwest A&F University

For the agroecosystems of the dairy cow industry, dietary carbohydrate（starch, neutral detergent fiber[NDF]） and fat could directly affect rumen methane emissions and host energy utilization. However, the relationships among diet, lactation performance, and methane emissions need to be further determined to assist dairy farms to adjust diet formulations and feeding strategies for environmental and production management. A meta-analysis was conducted in the current study to explore quantitative patterns of dietary fat and carbohydrate at different levels in balancing lactation performance and environment sustainability of dairy cows, and to establish a methane emission prediction model using the artificial neural network（ANN）model. The results showed that the regression relationship between dietary fat, carbohydrate and methane emissions could be shown by the following models: methane = 106.78 +（14.86 × DMI）, R2= 0.80;methane = 443.17-（46.41 × starch/NDF）, R2= 0.76; and methane = 388.91 +（31.40 × fat）-（5.42 × fat2）,R2= 0.80. The regression relationships between dietary fat, carbohydrate and lactation performance could be shown by the following models: milk fat yield = 1.08 +（0.43 × starch/NDF）-[0.34 ×（starch/NDF）2],R2= 0.79; milk protein yield = 0.68 +（0.15 × fat）-（0.016 × fat2）, R2= 0.82. In the structural equation model, we found that when formulating dietary carbohydrates and fats, it was necessary to balance the relationship between methane emissions and lactation performance. Specifically, dietary starch/NDF was lower than 0.63（extremum point） and dietary fat was between 2.89% and 4.69%（extremum point）, it could ensure that the aim of methane emission reduction（methane emissions decrease with increasing dietary starch/NDF and fat） was achieved without losing lactation performance of dairy cows（lactation performance increase with increasing dietary starch/NDF and fat）. Finally, we established the ANN model to predict methane emissions（training set: R2= 0.62; vali

关键词： Dietary fat and carbohydrate Environment sustainability Lactation performance Dairy cow Meta-analysis

Detection of avian influenza virus H9N_(2) based on self-driving and self-sensing microcantilever piezoelectric sensor

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Chinese Chemical Letters 2023年第4期34卷 464-468页

作者： Yawen zhang Feng Shi chenguang zhang Xin Sheng Yunhao Zhong Hui Chong Zhanjun Yang Chengyin Wang College of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

In this article, we used the self-excitation and self-inductance characteristics of polyvinylidene fluoride(PVDF) piezoelectric materials, combined with the powerful signal processing and calculation analysis capabilities of integrated circuits, for the first time to explore a set of microcantilever sensor "readout system" without additional driver(self-driving) and can realize self-sensing external signal(self-sensing).It was successfully applied to the unlabeled detection of avian influenza virus(AIV) H9N_(2). The specific force of the antigen-antibody complexes on the surface of the microcantilever leads to the change of the stress of the cantilever, which drives the constructed detection device, and does not require an additional excitation source to drive it, that is, the self-driving part. At the same time, due to the movement of piezoelectric charges in the film caused by the positive piezoelectric effect of the PVDF film, self-inductive charges are generated on the surface of the sensor dielectric. The charge signal is converted into a voltage signal, and the sensing part is completed, that is, self-sensing. The immunosensor has a linear range of100-1000 ng/m L with a detection limit of 2.9 ng/m L. The method will also open up a new avenue for the detection of other analytes based on antigen-antibody responses.

关键词： Micro cantilever sensor Self-driving Self-sensing Piezoelectric material Avian influenza virus H9N_(2)

扬子北缘马元铅锌矿床闪锌矿微量元素及S-Pb-He-Ar-C同位素地球化学研究

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岩石学报 2016年第1期32卷 251-263页

作者：高永宝李侃钱兵李文渊郑敏昌 chenguang zhang 中国地质调查局西安地质调查中心国土资源部岩浆作用成矿与找矿重点实验室西安710054 汉中天鸿基矿业有限公司汉中723102 加拿大女王大学地质科学与地质工程系

马元铅锌矿床是近年扬子陆块北缘铅锌找矿的新突破。矿体呈层状、似层状产于碑坝隆起翼部震旦系灯影组角砾状白云岩层间构造带中,围岩蚀变很弱。矿石中硫化物以闪锌矿、方铅矿为主,中粗粒晶质结构,充填于白云岩角砾间。闪锌矿富集Cd、Ge... 详细信息

马元铅锌矿床是近年扬子陆块北缘铅锌找矿的新突破。矿体呈层状、似层状产于碑坝隆起翼部震旦系灯影组角砾状白云岩层间构造带中,围岩蚀变很弱。矿石中硫化物以闪锌矿、方铅矿为主,中粗粒晶质结构,充填于白云岩角砾间。闪锌矿富集Cd、Ge、Ag,贫In、Tl、Se,Ga/In为6~132,Ge/In多>1000,成矿温度以中-低温为主。金属硫化物ε^(34)S值相对集中,为12.9‰~19.4‰,平均为17.4‰,来自于海相硫酸盐的还原。铅同位素组成稳定,^(206)Pb/^(204)Pb为17.858~17.918:^(207)Pb/^(204)Pb为15.603~15.694;^(208)Pb/^(204)Pb为37.756~38.046,具有造山带和上地壳铅的特征,震旦系可能提供了金属成矿物质。闪锌矿中流体包裹体的~3He/~4He为0.03Ra^1.05Ra,^(40)Ar/^(36)Ar为326.1~765.1,^(38)Ar/^(36)Ar为0.183~0.204,表明成矿流体主要为地壳流体和饱和大气水(大气降水或海水)的混合。闪锌矿内流体包裹体挥发分δ^(13)C_(CH_4)值为-36.01‰^-28.80‰,δ^(13)C_(C_2H_6)值为-27.72‰^-22.44‰,δ^(13)C_(CO_2)值为-23.24‰^-9.68‰,表明有机流体参与了成矿作用。石英、方解石的H-O同位素结果表明具有海水和有机水混合的特征。可见,成矿流体具有两种流体混合的特征,一为蒸发海水与围岩反应所形成的盆地卤水,二为有机流体。推测矿区可能存在一个古油气藏,由于TSR生成一高硫气藏,为区内还原性有机流体的主要来源。当富含Pb、Zn等成矿物质的成矿流体运移至富含CH_4和H_2S的还原性流体的矿区角砾岩带时,两种流体混合,Pb、Zn等遇到H_2S发生反应而沉淀成矿,并伴生热液白云石等,形成了马元铅锌矿床。综上所述,我们认为马元矿床属MVT型铅锌矿床。

关键词：闪锌矿微量元素 S-Pb-He-Ar-C同位素马元铅锌矿床扬子北缘