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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 25-36页

作者： jue zhu Longyuan LI Ningtao zhu Zhejiang Provincial Engineering Research Center for the Safety of Pressure Vessel and Pipeline Key Laboratory of Impact and Safety Engineering (Ningbo University) Ministry of Education School of Engineering Computing and Mathematics University of Plymouth Xi'an Zhanshi Testing & Engineering Co.Ltd.

Carbon nanotubes(CNTs) have garnered great attention in recent years due to their outstanding electrical, thermal, and mechanical properties. The incorporation of small amounts of CNTs in polymers can substantially improve the sensitivity of the polymer's electrical conductivity. This paper presents a modified Maxwell model to evaluate the electrical conductivity of CNTs-filled polymer composites by introducing a transition zone to account for the tunneling effect. In this modified Maxwell model, the CNTs-filled polymer composite is modeled as a three-phase composite, consisting of a matrix(polymer), inclusions(CNTs), and a transition zone(tunneling zone). The effective electrical conductivity(EEC) of the composite is calculated based on the volume fractions and electrical conductivities of the matrix, inclusions, and transition zone. The model's validity is confirmed through the use of available test data, which demonstrates its capability to accurately capture the nonlinear conductivity behavior observed in CNTs-polymer composites. This study offers valuable insights into the design of high-performance conductive polymer nanocomposites, and enhances the understanding of electrical conduction mechanisms in CNT-dispersed polymer composites.

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EQUIVALENT MODEL OF EXPANSION OF CEMENT MORTAR UNDER SULPHATE EROSION

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Acta Mechanica Solida Sinica 2008年第4期21卷 327-332页

作者： jue zhu Minqiang Jiang Jiankang Chen Mechanics and Materials Science Research Center Ningbo University Ningbo 315211 China State Key Laboratory of Nonlinear Mechanics （LNM） Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

The expansion property of cement mortar under the attack of sulfate ions is studied by experimental and theoretical methods. First, cement mortars are fabricated with the ratio of water to cement of 0.4, 0.6, and 0.8. Secondly, the expansion of specimen immerged in sulphate solution is measured at different times. Thirdly, a theoretical model of expansion of cement mortar under sulphate erosion is suggested by virtue of represent volume element method. In this model, the damage evolution due to the interaction between delayed ettringite and cement mortar is taken into account. Finally, the numerical calculation is results indicate that the model perfectly describes performed. The numerical and experimental the expansion of the cement mortar.

关键词： size effect microvoids expansion sodium sulfate attack

TRANSVERSAL INERTIAL EFFECT ON RELAXATION/RETARDATION TIME OF CEMENT MORTAR UNDER HARMONIC WAVE

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Acta Mechanica Solida Sinica 2008年第1期21卷 44-50页

作者： jue zhu Yonghui Cao Jiankang Chen Mechanics and Materials Science Research Center Ningbo University Ningbo 315211 China

Under dynamic loading, the constitutive relation of the cement mortar will be significantly affected by the transversal inertial effect of specimens with large diameters. In this paper, one-dimensional theoretical analysis is carried out to determine the transversal inertial effect on the relaxation/retardation time of the cement mortar under the harmonic wave. Relaxation time or retardation time is obtained by means of the wave velocity, attenuation coefficient and the frequency of the harmonic wave. Thus, the transversal inertial effect on the relaxation time from Maxwell model, as well as on retardation time from Voigt model is analyzed. The results show that the transversal inertial effect may lead to the increase of the relaxation time, but induce the decrease of the retardation time. Those should be taken into account when eliminating the transversal inertial effect in applications.

关键词： cement mortar harmonic wave viscoelastic model relaxation/retardation time

Underlying principle of efficient propulsion in flexible plunging foils

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Acta Mechanica Sinica 2014年第6期30卷 839-845页

作者： Xiao-jue zhu Guo-Wei He Xing Zhang LNM Institute of MechanicsChinese Academy of Sciences

Passive flexibility was found to enhance propulsive efficiency in swimming *** this study,we numerically investigate the roles of structural resonance and hydrodynamic wake resonance in optimizing efficiency of a flexible plunging *** results indicates that（1）optimal efficiency is not necessarily achieved when the driving frequency matches the structural eigenfrequency;（2）optimal efficiency always occurs when the driving frequency matches the wake resonant frequency of the time averaged velocity ***,the underlying principle of efficient propulsion in flexible plunging foil is the hydrodynamic wake resonance,rather than the structural *** addition,we also found that whether the efficiency can be optimized at the structural resonant point depends on the strength of the leading edge vortex relative to that of the trailing edge *** result of this work provides new insights into the role of passive flexibility in flapping-based propulsion.

关键词： Flexibility Propulsive efficiency Structural resonance Hydrodynamic wake resonance

Transcriptome research on spermatogenic molecular drive in mammals

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Asian Journal of Andrology 2015年第6期17卷 961-971,I0009页

作者： Zi-jue zhu Shi Yang Zheng Li Department of Urology Ren Ji Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200127 China Department of Andrology Urologic Medical CenterShanghai General Hospital Shanghai Jiao Tong University Shanghai 200080 China Shanghai Key Laboratory of Reproductive Medicine Shanghai 200025 China.

It is known that spermatogenic disorders are associated with genetic deficiency, although the primary mechanism is still unclear. It is difficult to demonstrate the molecular events occurring in testis, which contains germ cells at different developmental stages. However, transcriptomic methods can help us reveal the molecular drive of male gamete generation. Many transcriptomic studies have been performed on rodents by utilizing the timing of the first wave of spermatogenesis, which is not a suitable strategy for research in fertile men. With the development of separation methods for male germ cells, transcriptome research on the molecular drive of spermatogenesis in fertile men has seen great progress, and the results could be ultimately applied to improve the diagnosis and treatment for male infertility.

关键词： GeneChip germ cell RNA-Seq sorting spermatogenesis transcriptome

EXPERIMENTAL EVALUATION ON MODULUS OF EQUIVALENT HOMOGENEOUS ETTRINGITE

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Acta Mechanica Solida Sinica 2009年第4期22卷 320-327页

作者： Minghua Zhang Jiankang Chen jue zhu Jiangying Chen Department of Mechanics and Engineering Science Ningbo University Ningbo 315211 China

In the present study, the average modulus of delayed ettringite is evaluated by an experimental method combined with theoretical analysis. Firstly, the delayed ettringite crystal is synthesized by chemical reaction of Aluminum sulfate and calcium hydroxide. Secondly, specimens are obtained by compressing the delayed ettringite crystal under different pre-loads. Thirdly, the variation of the modulus of the specimen with different pre-loads is tested using Instron material test machine and the SHPB technique, respectively. It is found that the experimental data may be suitably fitted by Boltzmann Function. Finally, the porosity of the specimen is detected using the saturation method, and the effect of the porosity on the modulus is analyzed by the Eshelby＇s equivalent inclusion method and the Mori-Tanaka＇s scheme. The static and dynamic modulli of the equivalent homogeneous ettringite obtained in present study are approximately 10.64 GPa and 24.61 GPa, respectively.

关键词： ettringite equivalent homogeneous materials Boltzmann Function modulus

Effect of Indirect Transformation of Retained Austenite During Tempering on the Charpy Impact Toughness of a Low-Alloy Cr-Mo-V Steel

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Acta Metallurgica Sinica(English Letters) 2020年第10期33卷 1346-1358页

作者： Yong-Han Li Zhong-Hua Jiang Zhen-Dan Yang jue-Shun zhu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China

A modified tempering treatment has been designed in order to avoid the direct transformation of retained austenite(Ar)during tempering of a low-alloy Cr-Mo-V *** of the direct transformation of Ar into ferrite and M23C6 carbides during conventional tempering at 700℃,transformation into aggregate of ferrite and cementite has been forced by a pre-tempering at 455℃ before conventional *** have been performed on specimens quenched with cooling rates 1.5,3 and 12℃/s,providing different types of Ar within the as-quenched *** results show that the tempering modification does not improve the Charpy impact toughness at the highest quenching rate of 12℃/s,where the specimens cannot incur cleavage cracking induced from fine and discontinuous M23C6 carbides along lath *** the lowest quenching rate 1.5℃/s,the Charpy impact toughness can be improved,and the failure is dominated by carbide aggregates,which originate from the decomposed products of blocky *** is because the tempering modification effectively suppresses the formation of coarse M23C6 carbides at interfaces between the carbide aggregate and bainitic matrix,thereby resulting in a relatively homogeneous distribution of M23C6 carbides inside carbide ***,the tempering modification is recommended for large-scale forgings,in which relatively high quenching rates are difficult to achieve.

关键词： Bainite steel Retained austenite Impact toughness

DEVELOPMENT OF EXPERIMENTAL METHODS FOR IMPACT TESTING BY COMBINING HOPKINSON PRESSURE BAR WITH OTHER TECHNIQUES

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Acta Mechanica Solida Sinica 2014年第4期27卷 331-344页

作者： Lili Wang Shisheng Hu Liming Yang Zijian Sun jue zhu Huawei Lai Yuanyuan Ding Mechanics and Material Science Research Center Ningbo University Department of Modern Mechanics University of Science & Technology of China Huafeng Faculty Ningbo Polytechnic Department of Municipal Engineering Zhejiang University of Water Resources and Electric Power

The split Hopkinson pressure bar（SHPB） technique and the wave propagation inverse analysis（WPIA） technique are both extensively used to experimentally investigate the impact behavior of materials, although neither of them alone provides a fully satisfactory analysis. In the present paper, attention is given to new experimental techniques by incorporating a damagemodified constitutive model into the SHPB technique and combining the Hopkinson pressure bar（HPB） technique with WPIA. First, to distinguish the response due to dynamic constitutive behavior and the response due to dynamic damage evolution, the SHPB method incorporating a damage-modified constitutive model is developed, including an explicit damage-modified zhu–Wang–Tang model and an implicit damage-modified constitutive model. Second, when the SHPB results become invalid, a method of combining new Lagrange inverse analyses with the HPB technique is developed, including cases of the HPB arranged in front of a long specimen and behind the specimen. As examples of these new methods, typical results are given for nonlinear viscoelastic polymers and concretes considering damage evolution, a super-elastic Ti–Ni alloy with phase transformation and an aluminum foam with shock waves propagating within it.

关键词： Hopkinson pressure bar SHPB Lagrangian analysis high strain rate rate-dependent constitutive relation damage evolution

LOW DOSE PIRFENIDONE SUPPRESSES TRANSFORMING GROWTH FACTOR BETA-1 AND TISSUE INHIBITOR OF METALLOPROTEINASE-1, AND PROTECTS RATS FROM LUNG FIBROSIS INDUCED BY BLEOMYCIN

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Chinese Medical Sciences Journal 2006年第3期21卷 145-151页

作者： Xin-lun Tian Wei Yao Zi-jian Guo Li Gu Yuan-jue zhu Department of Respiratory Medicine Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆Peking Union Medical College Beijing 100730

Objective To investigate the optimal dosage of pirfenidone for the treatment of pulmonary fibrosis induced by bleomycin in Wistar rats, and the alteration of expressions of transforming growth factor beta-1 （ TGF-β1 ）, tissue inhibitor of metalloproteinase-1 （ TIMP-1 ）, and matrix metalloproteinase-13 （ MMP-13 ） in lung tissue. Methods Male Wistar rats were endotracheally instilled with bleomycin or normal saline. Pirfenidone （25-800 mg · kg^-l · d^-1 ）, dexamethasone （3 mg/kg）, or 1% carboxymethylcellulose sodium were given daily by feed 2 days before instillation of bleomycin. Groups T7 and T14 were fed pirfenidone 50 mg · kg^-1 · d^-1 at 7 days or 14 daYs after bleomycin instillation. Lungs were harvested at 28 days after bleomycin instillation. Patholological changes in luffg tissues were evaluated with HE staining. Lung collagen was stained by sirius red and measured by content of hydroxypro- line. Expression of proteins of TGF-β1 TIMP-1, and MMP-13 were detected by Western blotting. Results At doses of 25, 50, and 100 mg· kg^- 1 · d ^- 1, pirfenidone had significant anti-fibrotic effects for bleomy- cin-induced rat pulmonary fibrosis, and these effects were most significantly attenuated at the dosage of 50 mg · kg^-1 ·d^ -1（ HE： P 〈 0. 01, P 〈 0.01, and P = 0.064; sirius red： P 〈0.05, P 〈 0.01, and P 〈 0.05 ; hydroxyproline： P = 0.595, P 〈 0.01, and P = 0.976）. Pirfenidone at a dosage of 50 mg · kg^- l · d^-1 inhibited protein expression of TGF-131 and TIMP-1 in lung tissue in the early phase （0.79 and 0.75 times of control group）, but had no effect on ex- nr^eelnn nf MMP-13. Conclusion Low dose pirfenidone, especially at dosage of 50 mg · kg^-1 · d^-1, has significant anti-fibrotic effects on bleomycin-induced rat pulmonary fibrosis. Pirfenidone partially inhibits the enhancement of the expression of TGF-131 and TIMP-β1 in lung tissue.

关键词： pulmonary fibrosis bleomycin pirfenidone transforming growth factor beta-1 tissue inhibitor of metalloproteinase-1

A de novo frameshift mutation of the SRY gene leading to a patient with 46,XY complete gonadal dysgenesis

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Asian Journal of Andrology 2019年第5期21卷 522-524页

作者： Xiao-Bo Wang Yu-Long Liang Zi-jue zhu Yong zhu Peng Li Jia-Ping Cao Qun-Ying Zhang Qiang Liu Zheng Li Department of Andrology Center for Men's HealthInstitute of UrologyUrologic Medical CenterShanghai General HospitalShanghai 200080China Shanghai Key Laboratory of Reproductive Medicine Department of HistoembryologyGenetics and Developmental BiologyShanghai Jiao Tong University School of MedicineShanghai 200025China Department of Gynecology and Obstetrics Changxing Maternity and Child Health Care HospitalHuzhou 313199China

Dear Editor,Sex in mammals is genetically determined and defined at the cellular level by the sex chromosome constitution(XY males and XX females)and at the phenotypic level by the development of genderspecific anatomy,physiology,and behavior.146,XY complete gonadal dysgenesis(46,XY CGD),first reported by Swyer in 1955,^2 is a rare congenital condition with completely or partially disordered gonadal development,leading to discordance between the genetic,gonadal,and phenotypic *** patients have a 46,XY karyotype,a female phenotype,normal female external genitalia,and CGD("streak gonads")without sperm production and follicular or steroid function.

关键词： 46,XY anatomy gonadal