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Failure mechanism and infrared radiation characteristic of hard siltstone induced by stratification effect

Journal of Mountain Science 2024年第3期21卷 1058-1074页

作者： cheng yun SONG Zhanping XU Zhiwei YANG Tengtian TIAN Xiaoxu School of Civil Engineering Yancheng Institute of TechnologyYancheng 224051China School of Civil Engineering Xi'an University of Architecture and TechnologyXi'an 710055China Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering Xi'an 710055China China Railway Construction Bridge Engineering Bureau Group Co. Ltd.Tianjin 300300China

The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and temporal damage mechanism of hard siltstone. The uniaxial compression tests, coupled with acoustic emission(AE) and infrared radiation temperature(IRT) were conducted on siltstones with different stratification effects. The results revealed that the stratigraphic structure significantly affects the stress-strain response and strength degradation characteristics. The mechanical parameters exhibit anisotropy characteristics, and the stratification effect exhibits a negative correlation with the cracking stress and peak stress. The failure modes caused by the stratification effect show remarkable anisotropic features, including splitting failure(Ⅰ: 0°-22.50°, Ⅱ: 90°), composite failure(45°), and shearing failure(67.50°). The AE temporal sequences demonstrate a stepwise response characteristic to the loading stress level. The AE intensity indicates that the stress sensitivity of shearing failure and composite failure is generally greater than that of splitting failure. The IRT field has spatiotemporal migration and progressive dissimilation with stress loading and its dissimilation degree increases under higher stress levels. The stronger the stratification effect, the greater the dissimilation degree of the IRT field. The abnormal characteristic points of average infrared radiation temperature(AIRT) variance at local stress drop and peak stress can be used as early and late precursors to identify fracture instability. Theoretical analysis shows that the competitive relationship between compaction strengthening and fracturing damage intensifies the dissimilation of the infrared thermal field for an increasing stress level. The present study provides a theoretical reference for disaster warnings in hard sedimentary rock mass.

关键词： Hard siltstone Failure mechanism Stratification effect Infrared radiation characteristic Temporal-damage mechanism Dissimilation

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Preparation and performance evaluation of the slickwater using novel polymeric drag reducing agent with high temperature and shear resistance ability

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Petroleum Science 2024年第2期21卷 1113-1121页

作者： Ming-Wei Zhao Zhen-Feng Ma Cai-Li Dai WeiWu Yong-Quan Sun Xu-Guang Song yun-Long cheng Xiang-Yu Wang National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Shandong Key Laboratory of Oilfield Chemistry China University of Petroleum(East China)Qingdao266580ShandongChina Sinopec Shengli Oilfield Dongying257001ShandongChina Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 1H9Canada East China Petroleum Bureau of Sinopec Nanjing210011JiangsuChina

Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performance is severely affected at high temperatures.Drag reducing agent is the key to determine the drag reducing performance of slickwater.In this work,in order to further improve the temperature resistance of slickwater,a temperature-resistant polymeric drag reducing agent(PDRA)was synthesized and used as the basis for preparing the temperature-resistant slickwater.The slickwater system was prepared with the compositions of 0.2 wt%PDRA,0.05 wt%drainage aid nonylphenol polyoxyethylene ether phosphate(NPEP)and 0.5 wt%anti-expansion agent polyepichlorohydrindimethylamine(PDM).The drag reduction ability,rheology properties,temperature and shear resistance ability,and core damage property of slickwater were systematically studied and evaluated.In contrast to on-site drag reducing agent(DRA)and HPAM,the temperature-resistant slickwater demonstrates enhanced drag reduction efficacy at 90℃,exhibiting superior temperature and shear resistance ability.Notably,the drag reduction retention rate for the slickwater achieved an impressive 90.52%after a 30-min shearing period.Additionally,the core damage is only 5.53%.We expect that this study can broaden the application of slickwater in high-temperature reservoirs and provide a theoretical basis for field applications.

关键词： Unconventional resources Polymeric drag reducing agent Slickwater High drag reduction rate Temperature resistance

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A new energy-absorbing bolt used for large deformation control of tunnel surrounding rock

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International Journal of Mining Science and Technology 2022年第5期32卷 1031-1043页

作者： Junbao Wang Wei Liu Zhanping Song Lingfeng Li Shijin Feng yun cheng School of Civil Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Key Lab of Geotechnical and Underground Space Engineering Xi’an 710055China The 4th Engineering Co. Ltd.of China Railway 25th Bureau GroupLiuzhou 545007China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

In order to control the large deformation of tunnel surrounding rock,a new energy-absorbing bolt is developed.This bolt can be transformed into a rigid support when the deformation of the surrounding rock reaches the length of the sleeve tube,thus preventing the surrounding rock from continuing to deform.Moreover,this bolt has a simple structure and is easy to manufacture and assemble.Then the static tensile test is conducted on the bolt specimen to test its working performance.The test results show that when the cone angle of the cone block is small,the load–displacement curve of the bolt contains three stages;when the cone angle is large,the load–displacement curve contains only two stages.Meanwhile,both the average constant resistance and the maximum absorbed energy increase linearly with the increase of cone angle.On this basis,ignoring the influence of shear stress,and it is supposed that the thickness of the sleeve tube is constant,then the theoretical calculation formula of constant resistance for the new bolt is derived,and the rationality of the formula is verified using the static tensile test results.It is found that the error of the calculated result is less than 15%when the cone angle does not exceed 15.At last,the numerical simulation method is used to analyze the performance of the new bolt.The simulation results indicate that the generation of shear stress and the change of tube thickness during the movement of the cone block are two important factors that cause theoretical errors.

关键词： Energy-absorbing bolt Static tensile test Cone angle Constant resistance Limit ring

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王实甫《丽春堂》的题材、曲调和演出空间——基于元杂剧“文本流动性”的考察

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文艺研究 2024年第2期 101-113页

作者：程芸武汉大学文学院

《丽春堂》杂剧所具有的金代气息的题材、文辞,不必视为作者年代的投影,它们依托于明代内廷演剧这一特定的演出空间。明清曲谱、曲选存录的该剧若干曲调或曲段,提示了更为多样的文本状貌,但不可据以推定其“原貌”或“原本”。《丽春堂... 详细信息

《丽春堂》杂剧所具有的金代气息的题材、文辞,不必视为作者年代的投影,它们依托于明代内廷演剧这一特定的演出空间。明清曲谱、曲选存录的该剧若干曲调或曲段,提示了更为多样的文本状貌,但不可据以推定其“原貌”或“原本”。《丽春堂》除今存明刊本之外,可能还曾存在其他文本系统。《丽春堂》既保留了王实甫的原词,也沉淀了明代史官、内廷表演者以及后世编刊者的选择,或许还有金人旧曲的遗存,是一种流动的交织错落的文本。关于元杂剧“文本流动性”的讨论,可与“世代累积型集体创作”说形成方法论的对话,即每一个文本都寄身于具体的历史语境,有其特别的意义与功能。

关键词：王实甫丽春堂世代累积型集体创作元杂剧演出空间明刊本文本系统流动性

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具身共演、气氛空间与居间体验--“行为表演艺术”及其意义发生机制的现象学探析

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南京艺术学院学报（音乐与表演版） 2024年第3期 66-73,I0002,I0003页

作者：程赟四川美术学院重庆401331

20世纪60年代以来,西方艺术的“行为表演转向”催生了“行为表演艺术”。作为艺术的“行为表演”,一方面摒弃了角色扮演,将“表演”还原为演员具身行为的自指性展演;另一方面破除了观演二分,将观看还原为观众具身参与的合作性共演。因此... 详细信息

20世纪60年代以来,西方艺术的“行为表演转向”催生了“行为表演艺术”。作为艺术的“行为表演”,一方面摒弃了角色扮演,将“表演”还原为演员具身行为的自指性展演;另一方面破除了观演二分,将观看还原为观众具身参与的合作性共演。因此,行为表演艺术既不是现成的作品,也不仅是可写的文本,而是具身共演的事件。作为具身共演事件的“行为表演”,不是在与表演相分离的实体性剧场空间中按部就班地上演,而是在由行为表演的具身展演所开启的情感气氛空间中发生。如此这般的行为表演艺术具有独特的意义发生机制,即“具身共在—居间体验—情感空间—具身共演”机制,而居间体验是该机制的枢机。

关键词：行为表演具身共演情感气氛居间体验

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Research on the Intelligent Control Strategy of the Fuel Cell Phase-Shifting Full-Bridge Power Electronics DC-DC Converter

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Energy Engineering 2022年第1期119卷 387-405页

作者： Lei Zhang Yinlong Yuan Yihe Sun yun cheng Dian Wu Lei Ren School of Electrical Engineering Nantong UniversityNantong226019China School of Electrical and Power Engineering China University of Mining and TechnologyXuzhou221116China

focus of all countries.As an effective new energy,the fuel cell has attracted the attention of scholars.However,due to the particularity of proton exchange membrane fuel cell(PEMFC),the performance of traditional PI controlled phase-shifted full-bridge power electronics DC-DC converter cannot meet the needs of practical application.In order to further improve the dynamic performance of the converter,this paper first introduces several main topologies of the current mainstream front-end DC-DC converter,and analyzes their performance in the fuel cell system.Then,the operation process of the phase-shifted fullbridge power electronics DC-DC converter is introduced,and the shortcomings of the traditional PI control are analyzed.Finally,a double closed-loop adaptive fuzzy PI controller is proposed,which is characterized by dynamically adjusting PI parameters according to different working states to complete the intelligent control of phase-shifted full-bridge DC-DC converter.The simulation results in MATLAB/Simulink show that the proposed algorithm has good a control effect.Compared with the traditional algorithm,the overshoot and stabilization time of the system are shorter.The algorithm can effectively suppress the fluctuation of the output current of the fuel cell converter,and is a very practical control method.

关键词： Phase-shifted full-bridge adaptive fuzzy PI control proton exchange membrane fuel cell MATLAB/Simulink

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Journal of Computer Science & Technology 2024年第1期39卷 63-81页

作者：陈章玉华宇左鹏飞孙园园郭云程 Wuhan National Laboratory for Optoelectronics School of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China

Image bitmaps,i.e.,data containing pixels and visual perception,have been widely used in emerging applica-tions for pixel operations while consuming lots of memory space and energy.Compared with legacy DRAM(dynamic ran-dom access memory),non-volatile memories(NVMs)are suitable for bitmap storage due to the salient features of high density and intrinsic durability.However,writing NVMs suffers from higher energy consumption and latency compared with read accesses.Existing precise or approximate compression schemes in NVM controllers show limited performance for bitmaps due to the irregular data patterns and variance in bitmaps.We observe the pixel-level similarity when writing bitmaps due to the analogous contents in adjacent pixels.By exploiting the pixel-level similarity,we propose SimCom,an approximate similarity-aware compression scheme in the NVM module controller,to efficiently compress data for each write access on-the-fly.The idea behind SimCom is to compress continuous similar words into the pairs of base words with runs.The storage costs for small runs are further mitigated by reusing the least significant bits of base *** adaptively selects an appropriate compression mode for various bitmap formats,thus achieving an efficient trade-off be-tween quality and memory performance.We implement SimCom on GEM5/zsim with NVMain and evaluate the perfor-mance with real-world image/video workloads.Our results demonstrate the efficacy and efficiency of our SimCom with an efficient quality-performance trade-off.

关键词： approximate computing data compression memory architecture non-volatile memory

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外交环境风险影响审计费用吗?

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南京审计大学学报 2024年第2期21卷 24-34页

作者：程云文雯张坦北京外国语大学国际商学院北京100089 西安外国语大学商学院陕西西安710128

外交环境对于公司的海外发展具有重要影响。以2009—2022年外交部的发言表态次数为基础构建了公司暴露于外交环境风险的指标,检验了外交环境风险对公司审计费用的影响。实证结果表明,公司暴露于外交环境风险的程度越高,审计费用越高。... 详细信息

外交环境对于公司的海外发展具有重要影响。以2009—2022年外交部的发言表态次数为基础构建了公司暴露于外交环境风险的指标,检验了外交环境风险对公司审计费用的影响。实证结果表明,公司暴露于外交环境风险的程度越高,审计费用越高。区分审计师异质性后发现,外交环境风险更明显地提升了非国际“四大”的审计费用。机制分析显示,外交环境风险通过提高代理成本和审计投入提高了审计收费。研究结果表明宏观环境风险对审计决策具有影响,丰富了审计费用的影响因素研究。

关键词：外交环境风险对外直接投资审计费用代理成本审计投入审计风险

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数字经济能促进城市减霾降碳吗?——基于八大国家级大数据试验区的准自然实证分析

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软科学 2024年第1期38卷 8-15页

作者：程云洁段鑫新疆财经大学经济学院乌鲁木齐830012

基于2006-2019年我国264个城市的面板数据,实证检验了国家大数据试点政策对雾霾污染和碳排放的影响效应及作用机制。结果表明:国家级大数据试点政策促进了城市减霾降碳,且经过一系列稳健性检验后结论依旧成立。机制结果表明,国家级大数... 详细信息

基于2006-2019年我国264个城市的面板数据,实证检验了国家大数据试点政策对雾霾污染和碳排放的影响效应及作用机制。结果表明:国家级大数据试点政策促进了城市减霾降碳,且经过一系列稳健性检验后结论依旧成立。机制结果表明,国家级大数据试验区建设能够通过促进产业结构升级和提高机器人应用来降低雾霾污染和碳排放水平。异质性分析得出政策效果会随着试点城市的地理区位、人口规模、信息化水平和财政支出水平的不同而产生差异,其中东部地区、南方地区、大规模城市、高信息化水平和高财政支出水平的城市减霾降碳效果更明显。因此,应持续推进大数据试验区建设,完善信息基础设施建设,推进大数据在环境治理方面的深入应用,以充分发挥数字经济对城市雾霾污染和碳排放的改善作用。

关键词：国家级大数据试验区数字经济雾霾碳排放双重差分

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Effects of exogenous short-chain N-acyl homoserine lactone on denitrifying process of Paracoccus denitrificans

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Journal of Environmental Sciences 2017年第4期29卷 33-39页

作者： yun cheng Yang Zhang Qiuxuan Shen Jie Gao Guoqiang Zhuang Xuliang Zhuang School of Life Sciences University of Science and Technology of China CAS Key Laboratory of Environmental Biotechnology Research Center for Eco-Environmental SciencesChinese Academy of Sciences

N-acyl-homoserine lactones（AHLs） serve as quorum-sensing signals, which control a number of bacterial processes in many proteobacteria. Here we report the effects of exogenous short-chain AHL on the denitrifying process of Paracoccus denitrificans, which are capable of aerobic and anaerobic growth by utilizing nitrate. The denitrification activity of these cells was monitored by measuring denitrification products（including nitrate, nitrite,and nitrous oxide）, and the individual messenger ribonucleic acid（m RNA） levels of nitrate,nitrite, nitric oxide and nitrous oxide reductases. The results indicated that 2 μmol/L C6-homoserine lactone（HSL） has little effect on cell density under either anaerobic or aerobic culture conditions, and the nitrate reduction activity appeared slightly affected by N-hexanoyl-DL-homoserine lactone（C6-HSL）. However, exogenous C6-HSL significantly affected the transcription of nitrite reductase and nitric oxide reductase genes in P.denitrificans regardless of the presence of oxygen, and N2O accumulation activity in P. denitrificans was suppressed by C6-HSL under aerobic condition. In contrast, exogenous C6-HSL stimulated the production of N2O under anaerobic condition, suggesting that the regulation of denitrification by quorum sensing may be important in N2O release.

关键词： Quorum sensing N-acyl-homoserine lactones Denitrification activity Transcriptional regulation

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