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Journal of Central South University 2019年第3期26卷 567-576页

作者： YUAN zheng-cheng jiang zheng-wu CHEN Qing Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education School of Materials Science and Engineering Tongji University

The permeability modeling of self-healing due to calcium carbonate precipitation in cement-based materials with mineral additives was studied in this work. The parameters of calcium carbonate precipitation during self-healing were simulated. A permeability modeling of self-healing, combined with numerical simulation of calcium carbonate formation, was proposed based on the modified Poiseuille flow model. Moreover, the percentage of calcium carbonate in healing products was measured by TG-DTA. The simulated results show that self-healing can be dramatically promoted with the increase of pH and Ca2+ concentration. The calculated result of permeability is consistent with that measured for cracks appearing in middle or later stages of self-healing, it indicates that this model can be used to predict the self-healing rate to some extent. In addition, TG-DTA results show that the percentage of calcium carbonate in healing products is higher for mortar with only chemical expansion additives or cracks appearing in the later stage, which can more accurately predict the self-healing rate for the model.

关键词： cement-based material self-healing mineral additive calcium carbonate model

A Novel Extrinsic Fiber-Optic Fabry-Perot Strain Sensor System Based on Optical Amplification

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光学学报 2003年第S1期23卷 789-790页

作者： Yun-jiang Rao, Jian jiang, zheng-Lin Ran Department of Optoelectronic Engineering, Chongqing University, Chongqing 400044, China Department of Optoelectronic Engineering Chongqing University Chongqing 400044 China

A novel extrinsic fiber-optic Fabry-Perot interferometric strain sensor system is demonstrated based on the simultaneous use of the amplified spontaneous emission and optical amplification. The improvement of 3~4 orde... 详细信息

关键词： EFPI as et EDFA of ASE been

Micro RNAs in colorectal cancer:Role in metastasis and clinical perspectives

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World Journal of Gastroenterology 2014年第45期20卷 17011-17019页

作者： Shan Muhammad Kavanjit Kaur Rui Huang Qian Zhang Paviter Kaur Hamza Obaid Yazdani Muhammad Umar Bilal jiang zheng Liu zheng Xi-Shan Wang Colorectal Cancer Department the 2nd Affiliated Hospital of Harbin Medical University Harbin Medical University

Colorectal cancer (CRC) is the third most common malignancy and the third leading cause of cancer related deaths in the United States. Almost 90% of the patients diagnosed with CRC die due to metastases. MicroRNAs (miRNAs) are evolutionarily conserved molecules that modulate the expression of their target genes post-transcriptionally, and they may participate in various physiological and pathological processes including CRC metastasis by influencing various factors in the human body. Recently, the role miRNAs play throughout the CRC metastatic cascade has gain attention. Many studies have been published to link them with CRC metastasis. In this review, we will briefly discuss metastatic steps in the light of miRNAs, along with their target genes. We will discuss how the aberration in the expression of miRNAs leads to the formation of CRC by effecting the regulation of their target genes. As miRNAs are being exploited for diagnosis, prognosis, and monitoring of cancer and other diseases, their high tissue specificity and critical role in oncogenesis make them new biomarkers for the diagnosis and classification of cancer as well as for predicting patients’ outcome. MiRNA signatures have been identified for many human tumors including CRC, and miRNA-based therapies to treat cancer have been emphasized lately. These will also be discussed in this review.

关键词： microRNAs Colorectal Cancer Metastasis Biomarkers Therapeutics

New bisabolane-type phenolic sesquiterpenoids from the marine sponge Plakortis simplex

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Chinese Journal of Natural Medicines 2021年第8期19卷 626-631页

作者： WANG Jie LIU Li HONG Li-Li ZHAN Kai-Xuan LIN zheng-jiang JIAO Wei-Hua LIN Hou-Wen School of Food and Pharmacy Zhejiang Ocean UniversityZhoushan 316000China Research Center for Marine Drugs State Key Laboratory of Oncogenes and Related GenesDepartment of PharmacyRen Ji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Key Laboratory of Ministry of Education for TCM Viscera-State Theory and Applications Liaoning University of Traditional Chinese MedicineShenyang 110847China

Six new bisabolane-type phenolic sesquiterpenoids,including plakordiols A-D(1-4),(7 R,10 R)-hydroxycurcudiol(5)and(7 R,10 S)-hydroxycurcudiol(6)were isolated from the marine sponge Plakortis simplex collected from the South China *** structures were determined based on extensive analysis of spectroscopic *** configurations were assigned by coupling constant analysis,NOESY correlations,and the modified Mosher’s ***,their cytotoxic and antibacterial activities were evaluated.

关键词： Marine sponge Plakortis simplex Sesquiterpene phenols Plakordiols

Characterization of CoMn catalyst by in situ X-ray absorption spectroscopy and wavelet analysis for Fischer–Tropsch to olefins reaction

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Journal of Energy Chemistry 2019年第5期28卷 118-123页

作者： Ruoou Yang Zhaoming Xia Ziang Zhao Fanfei Sun Xianlong Du Haisheng Yu Songqi Gu Liangshu Zhong Jingtai Zhao Yunjie Ding zheng jiang Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Center for Applied Chemical Research Frontier Institute of Science and TechnologyXi'an Jiaotong UniversityXi'an 710049ShaanxiChina Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201203China

Cobalt carbide has recently been reported to catalyse the FTO con version of syngas with high selectivity for the production of lower olefins (C2-C4). Clarifying the formation process and atomic structure of cobalt carbide will help understand the catalytic mechanism of FTO. Herein, hydrogenati on of carb on monoxide was investigated for cobalt carbide synthesized from CoMn catalyst, followed by X-ray diffraction, transmission electron microscopy, temperature programmed reaction and in situ X-ray absorption spectroscopy. By monitoring the evolution of cobalt carbide during syngas conversion, the wavelet transform results give evidenee for the formation of the cobalt carbide and clearly demonstrate that the active site of catalysis was cobalt carbide.

关键词： In situ XAFS Wavelet transform Cobalt carbide FTO

BRITTLE-DUCTILE TRANSITION OF POLYMERS AND ITS PERCOLATION MODEL

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Chinese Journal of Polymer Science 2003年第2期21卷 129-134页

作者： Wei jiang Li-jia An Bing-zheng jiang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences, Changchun 130022, China Chinese Acad Sci Changchun Inst Appl Chem State Key Lab Polymer Phys & Chem Changchun 130022 Peoples R China

The brittle-ductile transition (BDT) of particlc toughened polymers was extensively studied in terms ofmorphology, strain rate, and temperature. The calculation results showed that both the critical interparticle distance (ID_c) andthe brittle-ductile transition temperature (T_(BD)) of polymers were a function of strain rate. The ID_c reduced nonlinearly withincreasing strain rate, whereas T_(BD) increased considerably with increasing strain rate. The effects of temperature andplasticizer concentration on BDT were discussed using a percolation model. The results were in agreement with theexperiments.

关键词： Particle toughening polymers Brittle-ductile transition Percolation

Understanding the synergetic interaction within α-MoC/β-Mo2C heterostructured electrocatalyst

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Journal of Energy Chemistry 2019年第8期28卷 66-70,I0004页

作者： Hao Zhang Haiyan Jin Yuqi Yang Fanfei Sun Yang Liu Xianlong Du Shuo Zhang Fei Song Jianqiang Wang Yong Wang zheng jiang Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204 China University of Chinese Academy of Sciences Beijing 100100 China Advanced Materials and Catalysis Group Institute of Catalysis Zhejiang UniversityHangzhou 310028 Zhejiang China

Constructing heterostructure is an important strategy to design efficient electrocatalysts. The synergetic interaction between dissimilar materials has been considered as the origin of the activity enhancement,however, the interfacial interaction is challenging to probe, thus, the underlying mechanism remains obscure. Here, we reported a heterostructured α-MoC/β-Mo2 C electrocatalyst for hydrogen evolution in alkaline media, which shows a significant electrocatalytic activity improvement as compared to the single component. Based on extensive characterizations including high-resolution transmission electron microscopy and X-ray absorption fine structure(XAFS) spectroscopy, together with density functional theory, we unraveled the synergetic interaction between α-MoC and β-Mo2 C, implying that α-Mo C sites are beneficial for water dissociation and hydrogen prefers to release on β-Mo2 C sites.

关键词： Hydrogen evolution reaction Heterostructure Molybdenum carbide Synergetic interaction Water dissociation

Role of local coordination in bimetallic sites for oxygen reduction: A theoretical analysis

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Journal of Energy Chemistry 2020年第5期29卷 131-137页

作者： Yuqi Yang Hao Zhang Zhaofeng Liang Yaru Yin Bingbao Mei Fei Song Fanfei Sun Songqi Gu zheng jiang Yuen Wu Zhiyuan Zhu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China Shanghai Synchrotron Radiation Facility Zhangjiang LaboratoryShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleiChEM(Collaborative Innovation Center of Chemistry for Energy Materials)University of Science and Technology of ChinaHefei 230026AnhuiChina ShanghaiTech University Shanghai 201210China

Understanding of the oxygen reduction reaction(ORR)mechanism for single atom catalysts is pivotal for the rational design of non-precious metal cathode materials and the commercialization of fuel ***,a series of non-precious metal electrocatalysts based on nitrogen-doped bimetallic(Fe and Co)carbide were modeled by density functional theory calculations to predict the corresponding reaction *** study elucidated prior oxygen adsorption on the Fe atom in the dual site and the modifier role of Co atoms to tune the electronic structures of *** reaction activity was highly correlated with the bimetallic center and the coordination environment of the adjacent ***,the preadsorption of*OH resulted in the apparent change of metal atoms'electronic states with the d-band center shifting toward the Fermi level,thereby boosting reaction *** result should help promote the fundamental understanding of active sites in ORR catalysts and provide an effective approach to the design of highly efficient ORR catalysts on an atomic scale.

关键词： Non-precious metal catalysts Bimetallic-sites Oxygen reduction reaction Density functional theory

Further research on public-key cryptosystems based on third-order recurrence sequence

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Frontiers of Electrical and Electronic Engineering in China 2006年第3期1卷 287-290页

作者： jiang zheng-tao SUN Xi TIAN Lei WANG Yu-min National Key laboratory of Integrated service Networks Xidian UniversityXi’an 710071China Present address:School of Computer Science Beihang UniversityBeijing 100083China National Key Laboratory of Integrated Service Networks Xidian UniversityXi’an 710071China Vocational College of Qingdao University Qingdao 266101China

Properties of third-order recurrence sequences were investigated and a new variant of the GH public-key cryptosystem,which was further improved to be a probabil-istic public-key cryptosystem,was *** security analysis of the proposed scheme was provided and it was proved that the one-wayness of the proposed scheme is equivalent to partial discrete logarithm and its semantic se-curity is equivalent to decisional Diffie-Hellman problem in ring ***,efficiency analysis of the proposed scheme was provided,and that these two encryption schemes need to transfer 2log N and 4log N bits data re-spectively.

关键词： public-key cryptosystem third-order linear recurrence sequence (trapdoor)discrete logarithm integer factorization

Potassium-promoted single-atom Co-N-C catalyst for direct dehydrogenation of ethylbenzene

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Nano Research 2023年第3期16卷 3687-3694页

作者： Jiajia Shi Yao Wei Leilei Zhang Dan Zhou Zhounan Yu Shengxin Zhang Xiaofeng Yang Ji Yang Yang Su zheng jiang Aiqin Wang CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

Alkali metals have been widely used as promoters of metal catalysts in various applications,yet the atomic understanding of the promotional mechanism remains *** this work,we for the first time report the significant promotional effect of potassium to the Co-N-C single-atom catalyst for the direct dehydrogenation of ethylbenzene.K cation was introduced by impregnation of Co-N-C with KCl followed by calcination at 600℃,which resulted in the bonding of K to the Co-O moiety of the Co-N-C catalyst as revealed by X-ray absorption spectroscopy in combination with theoretical *** formation of Co-O-K moiety led to the increase of electron density at the O atom due to electron transfer of K to O,and consequently facilitated the heterolytic cleavage of the C-H bond of ethylbenzene across the Co-O *** promotional effect of K was found to be a volcanofunction with the K/Co ratio and became the greatest at the K/Co ratio of 1.36,which resulted in the highest steady-state reaction rate of 9.7 mmolEB·gcat^(−1)·h^(−1)reported thus ***,the catalyst exhibited excellent stability during 100 h time on stream.

关键词： alkali metal potassium promoter alkane dehydrogenation single-atom catalyst Co-N-C