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Experimental Study on the Influence of Cross-Section Type of Marine Cable Conductors on the Bending Performance

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China Ocean Engineering 2022年第4期36卷 629-637页

作者： YAN Jun HU hai-tao LU hai-long YIN yuan-chao BU Yu-feng LU Qing-zhen State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInter-national Research Center for Computational MechanicsDalian University of TechnologyDalian 116024China Ningbo Research Institute of Dalian University of Technology Ningbo 315016China State Key Laboratory of Structural Analysis for Industrial Equipment School of Ocean Science and TechnologyDalian University of TechnologyPanjin 124221China

Through the development of marine energy,marine cables are the key equipment for transmission of electrical energy between surface platforms and underwater facilities.Fatigue failure is a critical failure mode of marine cables.The bending performance of the cable conductor has a major influence on both bending and fatigue performances of the overall cable structure.To study the influence of different types of the conductor cross-section on the bending performances of marine cable conductors,three types of copper conductors with the same cross-sectional area,i.e.,noncompressed round,compressed round,and shaped wire conductors,were selected.The experimental results demonstrated that the cross-section type significantly affects the bending performances of copper conductors.In particular,the bending stiffness of the shaped wire conductor is the highest among the three conductor types.Four key evaluation parameters,i.e.,the bending stiffness,maximum bending moment,envelope area,and engineering critical slip point,were selected to compare and analyze the bending hysteresis curves of the three copper conductors.The differences in the key evaluation parameters were analyzed based on the structural dimensional parameters,processing methods,and classical bending stiffness theoretical models of the three copper conductor types.The results provide an important theoretical guidance for the structural design and engineering applications of marine cable conductors.

关键词： marine cable conductors cross-section type bending performance theoretical model bending test

Bifurcations and Spatiotemporal Patterns in the Diffusive Nutrient-Microorganism Model

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Acta Mathematicae Applicatae Sinica 2024年

作者： Ya-di WANG hai-long yuan Yan-ling LI School of Mathematics and Information Science Shaanxi Normal University School of Arts and Sciences Shaanxi University of Science and Technology School of Mathematics and Statistics Xi'an Jiaotong University

In this paper, the diffusive nutrient-microorganism model subject to Neumann boundary conditions is considered. The Hopf bifurcations and steady state bifurcations which bifurcate from the positive constant equilibrium of the system are investigated in details. In addition, the formulae to determine the direction of Hopf and steady state bifurcations are derived. Our results show the existence of spatially homogeneous/nonhomogeneous periodic orbits and steady state solutions, which indicates the spatiotemporal dynamics of the system. Some numerical simulations are also presented to support the analytical results.

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Investigation on microstructures and properties of semi-solid Al_(80)Mg_(5)Li_(5)Zn_(5)Cu_(5)light-weight high-entropy alloy during isothermal heat treatment process

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China Foundry 2022年第6期19卷 519-527页

作者： Yong Hu yuan-yuan Liu long-zhi Zhao Yan-chuan Tang hai-tao Jiao De-jia Liu State Key Laboratory of Performance Monitoring Protecting of Rail Transit Infrastructure East China Jiaotong UniversityNanchang 330013China School of Materials Science and Engineering East China Jiaotong UniversityNanchang 330013China

The Al_(80)Mg_(5)Li_(5)Zn_(5)Cu_(5)light-weight high-entropy alloy with globular microstructure was fabricated by isothermal heat treatment.The effects of isothermal temperatures and holding times on the semi-solid microstructure evolution were investigated.The results indicate that,with increase of the isothermal temperature,the average grain size increases and the spheroidization time shortens.With prolongation of holding time,the shape factor increases firstly and then decreases,and the average grain size decreases at first and then increases when the isothermal temperature is below 520°C,however it increases gradually at 540℃.The optimal semi-solid microstructure is obtained at 520℃ for 30 min,whose shape factor and average grain size are 0.90 and 56.4μm,respectively.Compared with as-cast Al_(80)Mg_(5)Li_(5)Zn_(5)Cu_(5) light-weight high-entropy alloy,the compressive strength and plasticity of semi-solid Al_(80)Mg_(5)Li_(5)Zn_(5)Cu_(5) light-weight high-entropy alloy are increased by 36%and 108%,respectively.The formation of semi-solid microstructures includes three stages:melting separation,spheroidization,and coarsening growth.The sluggish diffusion effect of Al_(80)Mg_(5)Li_(5)Zn_(5)Cu_(5) light-weight high-entropy alloy leads to a low coarsening rate,resulting in slow grain growth.

关键词： light-weight high-entropy alloy semi-solid isothermal heat treatment microstructure

Mixed nanomicelles loaded with thymopeptides-sodium deoxycholate/phospholipid improve drug absorption

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Chinese Journal of Natural Medicines 2014年第1期12卷 65-70页

作者： JIN Shi-Xiao JIN Shi-Ying LV Qing-yuan FU Shan-Shan HAN Jin YUAN Hai-Long Department of Pharmacy 302 Military Hospital School of pharmaceutics Chengdu University of TCM

AIM: To improve the absorption of thymopeptides(TH) by preparing sodium deoxycholate/phospholipid-mixed nanomicelles(SDC/PL-MMs). METHODS: TH-SDC/PL-MMs were prepared by a film dispersion method, and then evaluated using photon correlation spectroscopy(PCS), zeta potential measurement, as well as their physical stability after storage for several days. Furthermore, in situ intestinal single-pass perfusion experiments and pharmacodynamics in immunodeficient mice were performed to make a comparison with TH powders and the control drug in absorption properties. RESULTS: A narrow size distribution of nanomicelles, with a mean particle size of(149 ± 8.32) nm and a zeta potential of(-31.05 ± 2.52) mV, was obtained. The in situ intestine perfusion experiments demonstrated a significant advantage in absorption characteristics for TH compared to the other formulations, and oral administration of TH-SDC/PL-MMs potentiated an equivalent effect with i.h. TH in pharmacodynamic studies in immunodeficient mice. CONCLUSIONS: TH-SDC/PL-MMs prepared by a film dispersion method are able to improve the absorption of TH. SDC/PL-MMs might be a good approach for the more effective delivery of drugs like TH.

关键词：中药学中药材植物药药理分析

宁夏荒漠草原区中间锦鸡儿灌丛群落碳水循环特征及其与生物环境因子的关系

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Journal of Plant Ecology 2022年第5期15卷 947-960页

作者： Ling-Tong Du long-long Ma hai-Zhu Pan Cheng-long Qiao Chen Meng Hong-Yue Wu Jing Tian Hong-Yi yuan Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China Ningxia UniversityYinchuan 750021China Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in Northwest China of Ministry of Education Ningxia UniversityYinchuan 750021China School of Ecology Environment Ningxia UniversityYinchuan 750021China

干旱半旱区的人工植被重建可能会改变陆地生态系统的重要生物物理过程星--碳水循环,然而在人类活动背景下,仍然缺乏对这些区域生态系统的碳水耦合机制的认识。本研究基于涡度相关系统测量了宁夏盐池荒漠草原区人工种植的中间锦鸡儿(Cara... 详细信息

干旱半旱区的人工植被重建可能会改变陆地生态系统的重要生物物理过程星--碳水循环,然而在人类活动背景下,仍然缺乏对这些区域生态系统的碳水耦合机制的认识。本研究基于涡度相关系统测量了宁夏盐池荒漠草原区人工种植的中间锦鸡儿(Caragana liouana)灌丛群落的CO_(2)和H_(2)O通量,通过分析总初级生产力(gross primary productivity,GPP)、蒸散发(evapotranspiration,ET)和水分利用效率(water use efficiency,WUE)的变化,探讨了人工灌从生态系统碳水通量及其耦合关系,并进一步分析驱动其变化的生物环境因子。研究结果表明,气候因子的季节变化导致了生物物理特征和碳水通量呈周期性变化。在生长季,GPP和ET波动较大,而WUE变化相对稳定。GPP、ET和WUE显著受辐射(global radiation,R_(g))、温度(T_(a)和T_(s))、水汽压亏缺、叶面积指数和植物水分胁迫指数(plant water stress index,PWSI)的驱动。其中R_(g)、温度和PWSI是影响WUE的最重要因素。R_(g)和温度会对WUE产生直接的促进作用,但同时也会间接地提高PWSI进而抑制WUE。PWSI会抑制光合作用和蒸腾作用,当植物水分胁迫超过一个阈值(PWSI>0.54)时,WUE会下降,这是因为GPP对植物水分胁迫的响应比ET更敏感。这些研究结果表明,在荒漠草原区通过大规模种植灌木可实现固碳的作用,但也必须充分考虑区域的水资源消耗和水分利用效率的状况。

关键词：涡度相关蒸散发(ET) 总初级生产力(CGPP) 水分利用效率(WUE) 荒漠草原中间锦鸡儿(Caragana liouana)

Optical coherence tomography findings in chronic progressive external ophthalmoplegia

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Chinese Medical Journal 2019年第10期132卷 1202-1207页

作者： yuan Wu Lei Kang hai-long Wu Yue Hou Zhao-Xia Wang Department of Ophthalmology Peking University First Hospital Beijing 100034 China Department of Neurology Peking University First Hospital Beijing 100034 China

Background: Chronic progressive external ophthalmoplegia (CPEO) is a mitochondrial encephalomyopathy caused by multiple mtDNA abnormalities. There is little information about the changes of ocular fundus with CPEO. The aim of this work was to measure and evaluate changes in the macular retinal thickness and optic nerve head in patients with CPEO using spectral-domain optical coherence tomography and to compare the findings with those of healthy individuals. Methods: Totally, 18 CPEO patients were enrolled in this study. Healthy volunteers matched for gender, age, and diopter settings were included as a control group. The retinal thickness of macular central fovea, inner and outer retinal layer thickness of perifoveal macular, optic nerve head parameters, and peripapillay retinal nerve fiber layer thickness (pRNFLT) for all included cases were measured using spectral-domain optical coherence tomography. A paired t test was used to compare the differences in the studied parameters between the two groups. The correlations between macular retinal thickness, pRNFLT, disease duration, and age of onset were also analyzed. Results: Among the macular parameters, retinal thickness of macular central fovea (t=—2.135, P < 0.05) and outer retinal layer thickness (t =—1.994, P < 0.05) of patients in the CPEO group were statistically significant lower than those of patients in the normal control group. For the optic nerve head parameters, the patients in the CPEO group showed a larger rim volume (t =—2.499, P < 0.05) and nerve head volume (t =—2.103, P < 0.05). The overall pRNFLT of patients in the CPEO group was statistically significant lower than that of patients in the control group (t =—4.125, P < 0.05). The comparison of pRNFLT in eight sectors showed that the pRNFLT of patients in the CPEO group was statistically significant lower than that of the control group mainly in the inferior and temporal sectors. The degree of pRNFL defect negatively correlated with the disease duration (r =—0.583, P < 0.05). Conclusions: The re

关键词： Optical coherence tomography Chronic progressive external ophthalmoplegia Retina Nerve fiber layer

General mechanism of spider toxin family I acting on sodium channel Nav1.7

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Zoological Research 2022年第5期43卷 886-896页

作者： Fu-Chu yuan Fu-De Sun Lin Zhang Biao Huang hai-long An Ming-Qiang Rong Can-Wei Du National&Local Joint Engineering Laboratory of Animal Peptide Drug Development College of Life SciencesHunan Normal UniversityChangshaHunan 410006China Key Laboratory of Molecular Biophysics Hebei ProvinceInstitute of BiophysicsSchool of Health Science&Biomedical EngineeringHebei University of TechnologyTianjin 300401China Chengdu Pepbiomedical Co. Ltd.ChengduSichuan 610219China

Various peptide toxins in animal venom inhibit voltage-gated sodium ion channel Nav1.7, including Nav-targeting spider toxin(NaSpTx) Family I. Toxins in NaSpTx Family I share a similar structure, i.e., Nterminal, loops 1–4, and C-terminal. Here, we used Mu-theraphotoxin-Ca2a(Ca2a), a peptide isolated from Cyriopagopus albostriatus, as a template to investigate the general properties of toxins in NaSpTx Family I. The toxins interacted with the cell membrane prior to binding to Nav1.7 via similar hydrophobic residues. Residues in loop 1, loop 4,and the C-terminal primarily interacted with the S3–S4 linker of domain II, especially basic amino acids binding to E818. We also identified the critical role of loop 2 in Ca2a regarding its affinity to Nav1.7.Our results provide further evidence that NaSpTx Family I toxins share similar structures and mechanisms of binding to Nav1.7.

关键词： Spider Nav1.7 Peptide toxin ICK motif

Comparison of anti-bacterial activity of three types of di-O-caffeoylquinic acids in Lonicera japonica flowers based on microcalorimetry

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Chinese Journal of Natural Medicines 2014年第2期12卷 108-113页

作者： HAN Jin LV Qing-yuan JIN Shi-Ying ZHANG Tian-Tian JIN Shi-Xiao LI Xian-Yi YUAN Hai-Long 302 Military Hospital of China Institute for Drug and Instrument Control Health Department GLD of PLA

The anti-bacterial activities of three types of di-O-caffeoylquinic acids(diCQAs) in Lonicera japonica flowers, a traditional Chinese medicine(TCM), on Bacillus shigae growth were investigated and compared by microcalorimetry. The three types of diCQAs were 3, 4-di-O-caffeoylquinic acid(3, 4-diCQA), 3, 5-di-O-caffeoylquinic acid(3, 5-diCQA), and 4, 5-di-O-caffeoylquinic acid(4, 5-diCQA). Some qualitative and quantitative information of the effects of the three diCQAs on metabolic power–time curves, growth rate constant k, maximum heat-output power Pm, and the generation time tG, total heat output Qt, and growth inhibitory ratio I of B. shigae were calculated. In accordance with a thermo-kinetic model, the corresponding quantitative relationships of k, Pm, Qt, I and c were established. Also, the half-inhibitory concentrations of the drugs(IC50) were obtained by quantitative analysis. Based on the quantity–activity relationships and the IC50 values, the sequence of inhibitory activity was 3, 5-diCQA > 4, 5-diCQA > 3, 4-diCQA. The results illustrate the possibility that the caffeoyl ester group at C-5 is the principal group that has a higher affinity for the bacterial cell, and that the intramolecular distance of the two caffeoyl ester groups also has an important influence on the anti-bacterial activities of the diCQAs.

关键词： di-O-caffeoylquinic acids Lonicera japonica Bacillus shigae Antibacterial activity Microcalorimetry

Improved stability and oral bioavailability of Ganneng dropping pills following transforming lignans of herpeto- spermum caudigerum into nanosuspensions

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Chinese Journal of Natural Medicines 2018年第1期16卷 70-80页

作者： LI Juan-Juan CHENG Ling SHEN Gang QIU Ling SHEN Cheng-Ying ZHENG Juan XU Rong YUAN Hai-Long Department of Pharmacy Air Force General Hospital of PLA Beijing 100142 China Department of Pharmacy Guangyuan Central Hospital Guanyuan 628000 China Department of Pharmacy Shuangliu District Maternal and Child Health Hospital Chengdu 610075 China Chengdu Institute of Chinese Herbal Medicine Chengdu 610045 China

The present study was designed to improve storage stability and oral bioavailability of Ganneng dropping pills(GNDP) by transforming lignans of Herpetospermum caudigerum(HL) composed of herpetrione(HPE) and herpetin(HPN) into nanosuspension(HL-NS), the main active ingredient of GNDP, HL-NS was prepared by high pressure homogenization and lyophilized to transform into solid nanoparticles(HL nanoparticles), and then the formulated HL nanoparticles were perfused into matrix to obtain NS-GNDP by melting method. For a period of 3 months, the content uniformity, storage stability and pharmacokinetics test in vivo of NS-GNDP were evaluated and compared with regular GNDP at room temperature. The results demonstrated that uniformity of dosage units of NS-GNDP was acceptable according to the criteria of Chinese Pharmacopoeia 2015 J. Physical stability of NS-GNDP was investigated systemically using photon correlation spectroscopy(PCS), zeta potential measurement, and scanning electron microscopy(SEM). There was a slight increase in particles and PI of HL-NS re-dispersed from NS-GNDP after storage for 3 months, compared with new formulated NS-GNDP, which indicated a good redispersibility of the NS-GNDP containing HL-NS after storage. Besides, chemical stability of NS-GNDP was studied and the results revealed that HPE and HPN degradation was less when compared with that of GNDP, providing more than 99% of drug residue after storage for 3 months. In the dissolution test in vitro, NS-GNDP remarkably exhibited an increased dissolution velocity compared with GNDP and no distinct dissolution difference existed within 3 months. The pharmacokinetic study showed that HPE and HPN in NS-GNDP exhibited a significant increase in AUC0–t, Cmax and decrease in Tmax when compared with regular GNDP. These results indicated that NS-GNDP possessed superiority with improved storage stability and increased dissolution rate and oral bioavailability.

关键词： Ganneng dropping pills Lignans Herpetospermum caudigerum Nanosuspensions Stability Oral bioavailability