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Friction 2022年第9期10卷 1393-1404页

作者： Fu wang Lunlin SHANG Guangan ZHANG zhaofeng wang State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Polyethylene glycol derived carbon quantum dots nanofluids were synthesized via a slow thermal oxidation *** size of carbon quantum dots was ca.2 nm and had a decreasing trend with the increase of oxidation *** used as lubricant in a diamond-like carbon film/bearing steel interface,the nanofluids achieved an ultra-low friction coefficient(μ≈0.02),much lower than that of original polyethylene glycol(μ=0.12).The worn surface analyses revealed that the nanofluids could effectively inhibit the tribo-oxidation of steel counterpart that occurred under original polyethylene glycol lubrication,and hence reduced the abrasion component of ***,the poly-hydroxyl carbon dots and oxidized polyethylene glycol species in nanofluids induced a hydroxyl-rich sliding interface via their tribochemical reactions with friction surfaces,which promoted the adsorption of polyethylene glycol molecules on sliding *** with the mild corrosion wear of steel counterface,this shifted the boundary lubrication to a mixed/film lubrication regime,thereby achieving an ultra-low friction *** above results suggest that the polyethylene glycol derived carbon quantum dots nanofluids should be a quite excellent candidate lubricant for solid–liquid synergy lubrication based on diamond-like carbon films.

关键词： polyethylene glycol diamond-like carbon films ultra-low friction synergy lubrication

脑源性神经营养因子介导帕金森病的运动防治:作用与机制

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中国组织工程研究 2025年第25期29卷 5454-5468页

作者：雷森林谌晓安陈平王兆锋吉首大学体育科学学院湖南省吉首市416000 北部湾大学体育学院广西壮族自治区钦州市535000

背景:运动干预作为经济有效的非物理疗法,可有效上调脑源性神经营养因子表达进而防治帕金森病发生发展,但目前关于靶向脑源性神经营养因子的运动治疗策略在延缓帕金森病发生发展的潜在作用机制尚不明晰。目的:以脑源性神经营养因子和帕... 详细信息

背景:运动干预作为经济有效的非物理疗法,可有效上调脑源性神经营养因子表达进而防治帕金森病发生发展,但目前关于靶向脑源性神经营养因子的运动治疗策略在延缓帕金森病发生发展的潜在作用机制尚不明晰。目的:以脑源性神经营养因子和帕金森病的关系为切入点,分析帕金森病病理状态下运动对脑源性神经营养因子表达的特异性调控作用及机制,梳理脑源性神经营养因子介导下不同运动方式对帕金森病的改善效果,并阐明靶向脑源性神经营养因子的运动治疗策略在防治帕金森病的潜在作用机制,旨在为运动防治帕金森病提供新的理论依据。方法:以“帕金森病,脑源性神经营养因子,神经保护,多巴胺,神经元异常凋亡,神经炎症反应,突触可塑性,运动”等为中文检索词;以“Parkinson’s disease,BDNF,Neuroprotection,neuroinflammation,synaptic plasticity”等为英文检索词,分别检索中国知网、万方数据库、PubMed和Web of Science数据库,搜寻各数据库建库至2024年2月发表的所有研究文献,根据纳排标准共获得核心相关文献98篇。结果与结论:①在帕金森病理背景下,运动可通过促进肌因子鸢尾素大量分泌,并降低色氨酸-犬尿氨酸代谢途径紊乱特异性调控脑源性神经营养因子表达。②有氧运动,尤其是特殊有氧运动(动物:旋转杆步行/人类:北欧健走)以及多模式运动可显著上调脑源性神经营养因子表达,进而改善帕金森病的运动症状,此外脑源性神经营养因子还介导身心运动(太极拳)对帕金森病患者认知障碍和睡眠障碍等非运动症状的有效调节。③运动诱导的高表达脑源性神经营养因子可能通过上调抗炎因子白细胞介素10、神经生长因子β和转化生长因子β表达,下调促炎因子肿瘤坏死因子α及白细胞介素1β表达,并抑制核转录因子κB信号通路表达降低小胶质细胞活性减轻神经炎症反应;增加酪氨酸羟化酶活性以促进多巴胺合成释放,并通过下调基质金属蛋白酶3及糖原合成酶激酶3β表达抑制α-突触核蛋白在丝氨酸129位点的磷酸化修饰,以防止神经异常凋亡;诱导突触效能的长时程增强发生,促进突触后致密区蛋白95及突触素大量表达以改善突触可塑性,发挥神经保护作。④鉴于脑源性神经营养因子在帕金森病发病进程及治疗中发挥重要作用,靶向脑源性神经营养因子的运动治疗策略将有助于推动帕金森病疾病“运动+药物”精准医疗的发展。但由于目前研究采用的运动处方较为单一,且研究焦点主要围绕运动症状而缺乏对非运动症状的考察,因此亟待学者采用更加统一和系统的运动处方,围绕非有氧运动类型对同一批帕金森病患者进行长期纵向跟踪研究,以此完善帕金森病运动防治领域研究的不足。

关键词：运动帕金森病脑源性神经营养因子神经保护神经炎症多巴胺 α-突触核蛋白突触可塑性神经元凋亡非运动症状

Investigating the Effects of Greenhouse Vegetable Cultivation on Soil Fertility in Lhasa, Tibetan Plateau

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Chinese Geographical Science 2020年第3期30卷 456-465页

作者： wang zhaofeng GONG Dianqing ZHANG Yili Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing100049China Chinese Acad-emy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China

The area of land utilized for growing vegetables in greenhouses has expanded rapidly on the Tibetan Plateau over recent decades. However, the effects of greenhouses on soil fertility as well as variations in these effects between the plateau and plain remain unclear on the Tibetan Plateau. This study assessed the effects of vegetable greenhouses in the vicinity of Lhasa, using open field soil as a control. A total of 92 plough layer(0-20 cm depth) soil samples including 54 from greenhouses and 38 from open fields were taken, and soil pH, electrical conductivity(EC), total soluble salt(TS), soil organic matter(SOM), total nitrogen(TN), available phosphorus(AP), and available potassium(AK) were measured. The results reveal that, soil pH was lower 1.0 units in greenhouses than that in open field. TS was higher 82% and AP was higher 160% overall. Similarly, SOM and TN were higher 32% and 46%, respectively, while AK changed slightly at a higher 1% rate. Results also show that soil properties varied depending on cultivation time and vegetable types. Overall, pH continuously decreased with cultivation time while other soil fertility indicators reached a maximum value after nine years of cultivation before starting to decrease. The effect of leafy vegetable planting on soil was slight overall, while the impact of fruits on soil was more serious. Compared with changes in plain greenhouse soil fertility measured across the eastern China, the effects of greenhouses on soil in Lhasa remain relatively limited;and the change in the degree of soil fertility was lower and the extreme values of soil fertility occurred later in Lhasa.

关键词： facility agriculture soil nutrient imbalance soil environment Lhasa Tibetan Plateau

Development of CASRock for modeling multi-fracture interactions in rocks under hydro-mechanical conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第11期16卷 4399-4415页

作者： Wenbo Hou Pengzhi Pan zhaofeng wang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

The interaction between multiple fractures is important in the analysis of rock fracture propagation,fracture network evolution and stability and integrity of rocks under hydro-mechanical(HM)coupling *** present,modeling the mechanical behavior of multiple fractures is still *** the condition of multiple fractures,the opening,closing,sliding,propagation and penetration of fractures become more *** order to simulate the HM coupling behavior of multi-fracture system,the paper presents a novel numerical scheme,including mesh reconstruction and topology generation algorithm,to efficiently and accurately represent fractures and their propagation process,and a potential function-based algorithm to address contact *** fracture contact algorithm does not need to set contact pairs and thus is suitable for complex contact situations from small to large deformations induced by HM *** topology of fracture interfaces is constructed by the dynamic adding algorithm,which makes the mesh reconstruction more rapid in the modeling of fracturing process,especially in the case of multiple fractures *** numerical scheme is implemented in CASRock,a self-developed numerical code,to simulate the propagation process of rock fractures and the interaction of multiple fractures under the condition of HM *** verify the suitability of the code,a series of tests were *** code was then applied to simulate hydraulic fracture propagation and fracture interactions caused by fluid *** ability of this method to study fracture propagation,multi-fracture interaction and fracture network evolution under hydro-mechanical coupling conditions is demonstrated.

关键词： CASRock Multi-fracture interaction Hydro-mechanical(HM)coupling Efficient grid reconstruction and topology generation Distributed contact computation

Pore characterization of different types of coal from coal and gas outburst disaster sites using low temperature nitrogen adsorption approach

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International Journal of Mining Science and Technology 2017年第2期27卷 371-377页

作者： Qi Lingling Tang Xu wang zhaofeng Peng Xinshan College of Safety Science and Engineering Henan Polytechnic UniversityJiaozuo 454000China MOE Engineering Center of Mine Disaster Prevention and Rescue Henan Polytechnic UniversityJiaozuo 454000China Virginia Center for Coal and Energy Research Virginia Polytechnic Institute and State UniversityVA 24061USA

To characterize the pore features of outburst coal samples and investigate whether outburst coal has some unique features or not, one of the authors, working as the member of the State Coal Mine Safety Committee of China, sampled nine outburst coal samples(coal powder and block) from outburst disaster sites in underground coal mines in China, and then analyzed the pore and surface features of these samples using low temperature nitrogen adsorption tests. Test data show that outburst powder and block coal samples have similar properties in both pore size distribution and surface area. With increasing coal rank, the proportion of micropores increases, which results in a higher surface area. The Jiulishan samples are rich in micropores, and other tested samples contain mainly mesopores, macropores and fewer micropores. Both the unclosed hysteresis loop and force closed desorption phenomena are observed in all tested samples. The former can be attributed to the instability of the meniscus condensation in pores,interconnected pore features of coal and the potential existence of ink-bottle pores, and the latter can be attributed to the non-rigid structure of coal and the gas affinity of coal.

关键词： Outburst coal Pore Nitrogen adsorption Coal and gas outburst

Passivated ZnSe nanocrystals prepared by hydrothermal methods and their optical properties

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Nano-Micro Letters 2010年第3期2卷 190-196页

作者： Lingling Peng Yuhua wang Qizheng Dong zhaofeng wang Department of Materials Science School of Physical Science and TechnologyLanzhou University

Homogeneous Zn Se nanocrystals were prepared via surfactant-assisted hydrothermal *** agent CTAB was used to control the particle morphology and the growth *** structure,morphology and optical properties of Zn Se nanocrystals have been investigated by XRD,TEM and luminescence *** results indicated that the size of Zn Se nanocrystals ranged from 3.0 nm to 5.0 nm with cubic zinc blende *** Se nanocrystals coated by CTAB were revealed high dispersibility and distribution under *** to the bulk Zn Se,the absorption edges and photoluminescence peaks of Zn Se nanocrystals were blue shifted to higher energies due to the quantum confinement *** emission intensity was strengthened after coated CTAB compared to bare *** was mainly due to the surface ***,we simply explored the formation mechanism of Zn Se nanocrystal in hydrothermal system.

关键词： Zinc selenide Nanocrystals Surface passivatiom Photoluminescence

A generalized nonlinear three-dimensional failure criterion based on fracture mechanics

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 630-640页

作者： zhaofeng wang Pengzhi Pan Jianping Zuo Yaohui Gao State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China School of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyBeijing100083China Power China Huadong Engineering Corporation Limited Hangzhou310014China

Based on fracture mechanics theory and wing crack model,a three-dimensional strength criterion for hard rock was developed in detail in this *** the basic expression is derived from initiation and propagation of a single crack,it can be extended to microcrack cluster so as to reflect the macroscopic failure ***,it can be derived as HoekeBrown criterion when the intermediate principal stress σ_(2) is equal to the minimum principal stress σ_(3)(Zuo et al.,2015).In addition,the opening direction of the microcrack cluster decreases with the increase of the intermediate principal stress coefficient,which could be described by an empirical function and verified by 10 kinds of hard *** strength is influenced by the coupled effect of stress level and the opening direction of the microcrack clusters related to the stress *** the effects of these two factors on the strength are opposite,the intermediate principal stress effect is induced.

关键词： Intermediate principal stress effect Rock strength Fracture mechanics True triaxial compression

Spatial network structure of transportation carbon emission efficiency in China and its influencing factors

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Chinese Journal of Population,Resources and Environment 2021年第4期19卷 295-303页

作者： Haiqin Shao zhaofeng wang School of Tourism Hunan Normal UniversityChangsha410081China

Grasping the spatial correlation structure of transportation carbon emission efficiency(TCEE)and its influencing factors is significant for promoting high-quality and coordinated development of the transportation industry and the relevant *** on the ideal point cross-efficiency(IPCE)model,the social network analysis method was employed herein to explore the spatial correlation network structure of China’s provincial TCEE and its influencing *** results obtained showed the following outcomes.(1)During the study period,China’s provincial TCEE formed a complex and multithreaded network association relationship,but its network association structure was still relatively loose and presented the hierarchical gradient characteristics of dense in the east and sparse in the west.(2)The correlation of China’s TCEE formed a block segmentation based on the regional boundaries,and its factional structure was relatively *** eastern region was closely connected with the central region,and generally connected with the western and northeastern *** central region was mainly connected with the eastern and western regions,and relatively less connected with the northeastern ***,the northeastern region was weakly connected with the western region.(3)Shanghai,Beijing,Zhejiang,Guangdong,Jiangsu,Tianjin,and other developed provinces were in the core leading position in the TCEE network,which significantly impacted the spatial correlation of ***,Heilongjiang,Jilin,Xinjiang,Qinghai,and other remote provinces in the northeast and northwest were at the absolute edge of the network,which weakly impacted the spatial correlation of TCEE.(4)Provincial distance,economic development-level difference,transportation intensity difference,and transportation structure difference had significant negative impacts on the spatial correlation network of China’s provincial *** contrast,the energy-saving technology level difference had a significant positiv

关键词： Transportation carbon emission efficiency Spatial network structure Influencing factor Social network analysis

Integrated approach of predicting rock stability in high mountain valley underground caverns

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Underground Space 2024年第6期19卷 317-341页

作者： Fuyuan Tan Haosen Guo Pengzhi Pan zhaofeng wang Xufeng Liu Yangyi Zhou East China Jiaotong University Nanchang 467200China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China Key Laboratory of Liaoning Province on Deep Engineering and Intelligent Technology Northeastern UniversityShenyang 110819China University of Chinese Academy of Sciences Beijing 100049China

High mountain valleys are characterized by the development of intricate ground stress fields due to geological processes such as tectonic stress,river erosion,and rock *** processes introduce considerable stability concerns in the surrounding rock formations for underground engineering projects in these regions,highlighting the imperative need for rigorous stability assessments during the design phase to ensure construction *** paper introduces an innovative approach for the pre-evaluation of the stability of surrounding rocks in underground caverns situated within high mountain *** methodology comprises several pivotal ***,we conduct inverse calculations of the ground stress field in complex geological terrains,combining field monitoring and numerical ***,we ascertain stress-strength ratios of the surrounding rocks using various rock strength *** assess the stability characteristics of the surrounding rocks in the 1^(#)spillway cave within our project area,we employ numerical simulations to compute stress-strength ratios based on different rock strength ***,we undertake a comparative analysis,utilizing data from the 5^(#)Underground Laboratory(Lab 5)of Jinping II Hydropower Station,aligning the chosen rock strength criterion with the damage characteristics of Lab 50s surrounding *** analysis serves as the cornerstone for evaluating other mechanical responses of the surrounding rocks,thereby validating the pre-evaluation *** pre-evaluation method takes into account the intricate geological evolution processes specific to high mountain *** also considers the influence of the initial geostress field within the geological range of underground *** comprehensive approach provides a robust foundation for the analysis and assessment of the stability of surrounding rocks,especially in high mountain valley areas,during the design phase of underground engi

关键词： High mountain valley Underground cavern Stability of surrounding rock On-site monitoring Stress-strength ratio Numerical simulation

A novel indirect optical method for rock stress measurement using microdeformation field analysis

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3616-3628页

作者： Yujie Feng Peng-Zhi Pan zhaofeng wang Xufeng Liu Shuting Miao State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Stress measurement plays a crucial role in geomechanics and rock engineering,especially for the design and construction of large-scale rock *** paper presents a novel method,based on the traditional stress relief approach,for indirectly measuring rock stress using optical *** proposed method allows for the acquisition of full-field strain evolution on the borehole’s inner wall before and after disturbance,facilitating the determination of three-dimensional(3D)stress information at multiple points within a single *** study focuses on presenting the method’s theoretical framework,laboratory validation results,and equipment design *** theoretical framework comprises three key components:the optical imaging method of the borehole wall,the digital image correlation(DIC)method,and the stress calculation *** validation tests investigate strain field distribution on the borehole wall under varying stress conditions,with stress results derived from DIC strain ***,the optical method demonstrates better measurement accuracy during the unloading stage compared to conventional strain gauge *** relatively high stress levels,the optical method demonstrates a relative error of less than 7%and an absolute error within 0.5 ***,a comparative analysis between the optical method and the conventional contact resistance strain gauge method highlights the optical method’s enhanced accuracy and stability,particularly during the unloading *** proposed optical stress measurement device represents a pioneering effort in the application of DIC technology to rock engineering,highlighting its potential to advance stress measurement techniques in the field.

关键词： Rock stress measurement Optical technology Digital image correlation(DIC)technology Micro-deformation field