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Composite rock-breaking of high-pressure CO_(2)jet&polycrystallinediamond-compact(PDC)cutter using a coupled SPH/FEM model

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International Journal of Mining Science and Technology 2022年第5期32卷 1115-1124页

作者： Can Cai Pei Zhang Daping Xu Xianpeng Yang yingfang zhou School of Mechanical Engineering Southwest Petroleum UniversityChengdu 610500China Key Laboratory of Groundwater Resources and Environment Jilin UniversityMinistry of EducationChangchun 130021China Laboratory of High-pressure Jet Theory and Application Technology Southwest Petroleum UniversityChengdu 610599China School of Engineering University of AberdeenAberdeen AB243FXUnited Kingdom School of Intelligent Manufacturing Panzhihua UniversityPanzhihua 617000China

CO_(2) drilling is a promising underbalance drilling technology with great advantages,such as lower cutting force,intense cooling and excellent ***,in the underbalance drilling,the mechanism of the coupling CO_(2) jet and polycrystalline-diamond-compact(PDC)cutter are still ***,we established a coupled smoothed particle hydrodynamics/finite element method(SPH/FEM)model to simulate the composite rock-breaking of high-pressure CO_(2) jet&PDC *** with the experimental research results,the mechanism of composite rock-breaking is studied from the perspectives of rock stress field,cutting force and jet *** results show that the composite rock-breaking can effectively relieve the influence of vibration and shock on PDC ***,the high-pressure CO_(2) jet has a positive effect on carrying rock debris,which can effectively reduce the temperature rising and the thermal wear of the PDC *** addition,the effects of CO_(2) jet parameters on composite rock-breaking were studied,such as jet impact velocity,nozzle diameter,jet injection angle and impact *** studies show that when the impact velocity of the CO_(2) jet is greater than 250 m/s,the CO_(2) jet could quickly break the *** is found that the optimal range of nozzle diameter is 1.5–2.5 mm,the best injection angle of CO_(2) jet is 60,the optimal impact distance is 10 times the nozzle *** above studies could provide theoretical supports and technical guidance for composite rock-breaking,which is useful for the CO_(2) underbalance drilling and drill bit design.

关键词： C0_(2)drilling High-pressure C0_(2)jet&PDC cutter Composite rock-breaking Experimental study SPH/FEM method

Factors influencing methane diffusion behaviors in micro-nano coal pores: a comprehensive study

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Frontiers of Earth Science 2023年第1期17卷 71-86页

作者： Xianglong FANG Dameng LIU yingfang zhou Xiaobo LIU Yidong CAI School of Energy Resources China University of GeosciencesBeijing 100083China Coal Reservoir Laboratory of National Engineering Research Center of CBM Development&Utilization China University of GeosciencesBeijing 100083China School of Engineering Fraser Noble BuildingKing's CollegeUniversity of AberdeenAB243UE AberdeenUK Postdoctoral Workstation of Applied Technology Research Institute Northeast Petroleum UniversityDaqing 163318China

Gas diffusion in the coal matrix plays a significant role in forecasting the production performance of coalbed methane(CBM)*** better understand methane diffusion behavior,a systematic study was performed on various rank coals with vitrinite reflectance(Ro,m)ranging from 0.46%to 2.79%.Multiple experiments,including coal petrographic analysis,field emission scanning electron microscopy(FESEM),low-temperature N2 adsorption/desorption,and mercury intrusion porosimetry(MIP),were conducted to quantitatively characterize the multiscale micro-nano pore system in different rank coals,which showed that the pore structure of coals exhibited a multimodal pore size and volume *** adsorption-diffusion experiments using the volumetric method were also performed to understand the methane diffusion characteristics in the micro-nano pores of the coal *** applicability of the multiporous diffusion model is verified,and methane diffusion in the multi-scale pores of coal reservoirs exhibits the characteristics of early fast diffusion,transitional diffusion in the medium term,and slow diffusion in the later *** addition,the factors affecting methane diffusion in coals were systematically analyzed,and gray relational analysis(GRA)was employed to analyze and identify the importance of these factors on methane *** results show the impact ranking of factors,in order from the most important to the least:particle size>moisture>surface area>pore volume>pressure>coal rank>temperature in all of three diffusion *** findings are helpful for forecasting production performance and enhancing the production efficiency of CBM.

关键词： coalbed methane reservoir micro-characteristic diffusion coefficient grey relational analysis

Theoretical calculation of high-pressure CO_(2)jet in cases of composite rock-breaking based on span-wagner equation of state

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Journal of Hydrodynamics 2022年第5期34卷 948-964页

作者： Xian-peng Yang Can Cai Xiao-hua Chen Pei Zhang Xin Zeng Chi Peng yingfang zhou Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan Province School of Mechanical EngineeringSouthwest Petroleum UniversityChengdu610500China School of Engineering University of AberdeenAberdeenUK Laboratory of High-pressure Jet Theory and Application Technology Southwest Petroleum UniversityChengdu610599China Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin UniversityChangchun130021China Southwest Pipeline Co. Ltd.National Pipe Network GroupChengdu610064China

Although several theoretical calculation methods for high-pressure jet are available,there is currently no theoretical model for the high-pressure CO_(2)jet based on the high-precision equation of state(EOS).To investigate the flow field of the high-pressure CO_(2)jet in cases of the composite rock-breaking under the high-pressure CO_(2)Jet and PDC cutter,a semi-analytical approach of the high-pressure CO_(2)jet is developed based on the Span-Wagner EOS and CO_(2)jet *** semi-analytical calculations and the physical property calculations under the action of the high-pressure CO_(2)jet are conducted with consideration of the jet pressure,the jet distance,the nozzle diameter and the jet *** results indicate that the distribution of the physical properties calculated by the semi-analytical approaches is similar to that obtained by experimental monitoring and numerical simulation,which indicates that the calculation method of the high-pressure CO_(2)jet presented in this paper is effective and *** properties of the CO_(2)jet obtained by the theoretical calculation see a significant difference between the initial region and the jet impact *** the temperature of 300 K,the increase of the initial pressure can effectively increase the impact force and the cooling ability of the *** proportion of the jet core lengths in the jet on the axis increases with the increase of the ratio of the nozzle diameter to the jet length,accompanied with the increase of the impact force of the *** increase of the jet angle can effectively increase the impacting force of the jet,but hampers the fluid *** study combines the theoretical calculation of the jet with the calculation of the physical properties of the high-pressure CO_(2),for comprehensively understanding the CO_(2)jet field in the composite rock-breaking under the action of the high-pressure CO_(2)jet and PDC *** theoretical calculation of the CO_(2)jet based on the high-precisio

关键词： CO_(2)jet hydraulic jet drill theoretical calculation equation of state(EOS) physical property

P-wave and S-wave response of coal rock containing gas-water with different saturation: an experimental perspective

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Frontiers of Earth Science 2023年第1期17卷 100-108页

作者： Dameng LIU Lijing LI Zheng ZHAO Wei CHEN Yidong CAI Yongkai QIU yingfang zhou School of Energy Resources China University of GeosciencesBeijing 100083China Coal Reservoir Laboratory of Natural Engineering Research Center of CBM Development&Utilization China University of GeosciencesBeijing 100083China Beijing Furuibao Energy Technology Company Beijing 100176China School of Engineering King’s CollegeUniversity of AberdeenAB243UE AberdeenUK

The acoustic response of gas and/or water saturated coal rock is fundamental for establishing the correspondence between the physical properties of the coal reservoir and the characteristics of the well-logging response,which is the technology essential for the geophysical exploration of coalbed methane(CBM).This acoustic response depends on water(Sw)and gas(Sg)saturation among other *** this study,we performed acoustic tests on dry and different gas-water saturated coal samples with different degrees of metamorphism and deformation,collected from several coal mining areas in *** tests enabled us to analyze the influence of coal type and gas-water saturation on the acoustic response of CBM *** results show that the acoustic velocity of P-wave and S-wave(Vp and Vs,respectively),and the relative anisotropy of and Vs,increased with increasing vitrinite reflectance,density,Vp and *** increasing from 0 to 100%,the growth rate of the acoustic velocity decreased with increasing vitrinite *** Vp/Vs ratio of tectonic coal was generally higher than that of primary *** growth rate of the relative anisotropy in tectonic coal was markedly higher than that in primary coal.

关键词： coal rock gas-water water saturation acoustic velocity relative anisotropy

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要重视青少年子宫腺肌病的早期诊治

中华妇产科杂志 2023年第7期58卷 485-488页

作者：彭超周应芳北京大学第一医院妇产科北京100034 北京大学第一医院宁夏妇女儿童医院银川750002

青少年子宫腺肌病并不少见,主要症状是痛经和月经过多,一般是进展性疾病。本文从病因、高危因素、发病年龄、临床表现、诊断、治疗等方面与大家一起探讨青少年子宫腺肌病,并呼吁大家要重视青少年子宫腺肌病的早期诊治。超声等影像学检... 详细信息

青少年子宫腺肌病并不少见,主要症状是痛经和月经过多,一般是进展性疾病。本文从病因、高危因素、发病年龄、临床表现、诊断、治疗等方面与大家一起探讨青少年子宫腺肌病,并呼吁大家要重视青少年子宫腺肌病的早期诊治。超声等影像学检查可以早期发现、早期诊断青少年子宫腺肌病。青少年子宫腺肌病的治疗不仅要缓解疼痛、减少出血,还要注重延缓疾病进展。子宫明显增大或合并子宫肌瘤者,推荐使用促性腺激素释放激素激动剂配合"反向添加"作为长期维持治疗直至尝试生育。青少年还处于生长发育阶段,长期用药时更应注意不良反应。各种药物的疗效及适应证和禁忌证存在区别,选择药物治疗时需个体化。

关键词：促性腺激素释放激素激动剂月经过多长期用药发病年龄子宫腺肌病早期诊治合并子宫肌瘤生长发育阶段

Sport medicine among the past three decades in China

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Chinese Medical Journal 2024年第7期137卷 757-761页

作者： yingfang Ao Wenqiang Yan Yue Wu Institute of Sports Medicine of Peking University Beijing 100191China Beijing Key Laboratory of Sports Injuries Beijing 100191China

In 1955,Professor Mianyu Qu,the founder of Chinese sports medicine,and the older generation of sports medicine practitioners,founded China’s sports medicine in response to the needs of the development of national sports and *** therst 30 years of the establishment of sports medicine,they played an important role in the academic development,talent cultivation,international communication,construction of the society and organization,national Olympic glory,and national*** contributions established a solid foundation for the rapid development of China’s sports medicine in the following 30 years.

关键词： sports academic medicine

Damage Diagnosis of Bleacher Based on an Enhanced Convolutional Neural Network with Training Interference

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Structural Durability & Health Monitoring 2024年第3期18卷 321-339页

作者： Chaozhi Cai Xiaoyu Guo yingfang Xue Jianhua Ren School of Mechanical and Equipment Engineering Hebei University of EngineeringHandan056038China

Bleachers play a crucial role in practical engineering applications, and any damage incurred during their operationposes a significant threat to the safety of both life and property. Consequently, it becomes imperative to conductdamage diagnosis and health monitoring of bleachers. The intricate structure of bleachers, the varied types ofpotential damage, and the presence of similar vibration data in adjacent locations make it challenging to achievesatisfactory diagnosis accuracy through traditional time-frequency analysis methods. Furthermore, field environmentalnoise can adversely impact the accuracy of bleacher damage diagnosis. To enhance the accuracy and antinoisecapabilities of bleacher damage diagnosis, this paper proposes improvements to the existing ConvolutionalNeural Network with Training Interference (TICNN). The result is an advanced Convolutional Neural Networkmodel with superior accuracy and robust anti-noise capabilities, referred to as Enhanced TICNN (ETICNN).ETICNN autonomously extracts optimal damage-sensitive features from the original vibration data. To validatethe superiority of the proposed ETICNN, experiments are conducted using the bleacher model from Qatar Universityas the subject. Comparative studies under identical experimental conditions involve TICNN, Deep ConvolutionalNeural Networks with wide first-layer kernels (WDCNN), and One-Dimensional ConvolutionalNeural Network (1DCNN). The experimental findings demonstrate that the ETICNN model achieves the highestaccuracy, approximately 99%, and exhibits robust classification abilities in both Phases I and II of the damagediagnosis experiments. Simultaneously, the ETICNN model demonstrates strong anti-noise capabilities, outperformingTICNN by 3% to 4% and surpassing other models in performance.

关键词： Bleacher vibration signal damage diagnosis convolutional neural network anti-noise ability

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子宫腺肌病的药物治疗进展

山东大学学报（医学版） 2022年第7期60卷 20-25页

作者：彭超周应芳北京大学第一医院妇产科北京100034

缓解疼痛,减少出血和促进生育是子宫腺肌病的主要治疗目标。腺肌病药物治疗选择与子宫内膜异位症类似,有非甾体类抗炎药、促性腺激素释放激素类似物(GnRH-a)、复方口服避孕药、孕激素类药物以及中医中药等五大类。子宫腺肌病是一种慢性... 详细信息

缓解疼痛,减少出血和促进生育是子宫腺肌病的主要治疗目标。腺肌病药物治疗选择与子宫内膜异位症类似,有非甾体类抗炎药、促性腺激素释放激素类似物(GnRH-a)、复方口服避孕药、孕激素类药物以及中医中药等五大类。子宫腺肌病是一种慢性疾病,需要长期管理。

关键词：子宫腺肌病药物治疗长期管理

4天香烟烟雾暴露联合poly(I:C)刺激对小鼠肺部免疫应答及干扰素表达的影响

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中国免疫学杂志 2024年第1期40卷 67-71页

作者：董晓飞梁紫尧范龙全景羽林琳周颖芳吴蕾于旭华广州医科大学广州510150 广州中医药大学第二附属医院广州510120 粤港澳中医药与免疫疾病研究联合实验室广州510290

目的:探讨短期香烟烟雾暴露联合poly(I:C)刺激对小鼠肺部免疫应答及干扰素表达的影响。方法:BALB/c小鼠随机分为4组:对照组、熏烟组、poly(I:C)组和熏烟联合poly(I:C)组。检测支气管肺泡灌洗液(BALF)中总细胞数及细胞分类计数;普通光镜... 详细信息

目的:探讨短期香烟烟雾暴露联合poly(I:C)刺激对小鼠肺部免疫应答及干扰素表达的影响。方法:BALB/c小鼠随机分为4组:对照组、熏烟组、poly(I:C)组和熏烟联合poly(I:C)组。检测支气管肺泡灌洗液(BALF)中总细胞数及细胞分类计数;普通光镜下观察各组细胞形态;荧光定量PCR检测肺组织细胞因子、趋化因子和干扰素及干扰素刺激基因表达。结果:与对照组相比,熏烟联合poly(I:C)组总细胞数计数、巨噬细胞与中性粒细胞计数明显升高(P<0.05),且熏烟联合poly(I:C)组巨噬细胞计数高于poly(I:C)组;与poly(I:C)组比较,熏烟联合poly(I:C)组小鼠气道灌洗液巨噬细胞体积较大,呈圆形或不规则形,细胞质较多空泡;与对照组相比,熏烟联合poly(I:C)组小鼠肺组织中性粒细胞趋化因子CXCL1(P<0.05)、CXCL2(P<0.01)和淋巴细胞趋化因子CCL2(P<0.01)mRNA表达升高,肺组织IL-1β、IL-6、TNF-αmRNA表达明显升高(P<0.01),肺组织IFN-β(P<0.01)、IFN-γ(P<0.05)、MX2(P<0.01)和IP-10(P<0.01)表达显著升高,且与poly(I:C)组小鼠相比,熏烟联合poly(I:C)组小鼠肺组织CXCL2(P<0.05)、TNF-α(P<0.01)和IFN-β(P<0.05)mRNA表达明显升高。结论:熏烟联合poly(I:C)诱导了小鼠肺部炎症反应和干扰素及干扰素刺激基因表达。同时,香烟暴露加剧了poly(I:C)诱导的小鼠肺部急性炎症反应和Ⅰ型干扰素表达。

关键词：香烟烟雾 poly(I:C) 免疫细胞气道炎症干扰素

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