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Assessing the range of blasting-induced cracks in the surrounding rock of deeply buried tunnels based on the unified strength theory

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Journal of Central South University 2024年第7期31卷 2341-2364页

作者： LI Liang CHEN Jia-jun ZHAO Lian-heng HE ke-pei HU Shi-hong LI Hua-long School of Civil Engineering Central South UniversityChangsha 410075China key Laboratory of Heavy-haul Railway Engineering Structure Ministry of EducationCentral South UniversityChangsha 410075China Hunan Provincial key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering Structure Central South UniversityChangsha 410075China

Blasting-induced cracks in the rock surrounding deeply buried tunnels can result in water gushing and rock mass collapse,posing significant safety ***,previous theoretical studies on the range of blasting-induced cracks often ignore the impact of the in-situ stress,especially that of the intermediate principal *** particle displacement−crack radius relationship was established in this paper by utilizing the blasthole cavity expansion equation,and theoretical analytical formulas of the stress−displacement relationship and the crack radius were derived with unified strength theory to accurately assess the range of cracks in deep surrounding rock under a blasting *** analysis showed that the crushing zone size was positively correlated with in-situ stress,intermediate principal stress,and detonation pressure,whereas negatively correlated with Poisson ratio and decoupling *** dilatancy angle-crushing zone size relationship exhibited nonmonotonic *** relationships in the crushing zone and the fracture zone exhibited opposite trends under the influence of only in-situ stress or intermediate principal *** the in-situ stress increased from 0 to 70 MPa,the rate of change in the crack range and the attenuation rate of the peak vibration velocity gradually slowed.

关键词： deep drilling and blasting cracks in surrounding rock unified strength theory intermediate principle stress in-situ stress cavity expansion dilatancy characteristics

Evaluation of the injection and plugging ability of a novel epoxy resin in cement cracks

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Petroleum Science 2024年第2期21卷 1211-1220页

作者： Guang-Yao Leng Wei Yan Hai-Mu Ye Er-Dong Yao Ji-Bin Duan Zheng-Xian Xu ke-pei Li Jing-Ru Zhang Zhong Li State key Laboratory of Petroleum Resource&Prospecting China University of Petroleum(Beijing)Beijing102249China CNPC Liaohe Oilfield Gas Storage Co.LTD Panjin124000LiaoningChina CNOOC Research Institute Co. Ltd.Beijing100028China

Sustained casing pressure(SCP)is a crucial issue in the oil and gas production *** resins,exhibiting exceptional compressive strength,ductility,and shear bonding strength,have the potential to form reliable *** injectivity and sealing capacity of the epoxy resin is crucial parameters for the success of shallow remediation *** study aimed to develop and assess a novel solid-free resin sealant as an alternative to Portland cement for mitigating fluid *** investigation evaluated the viscosity,compressive strength,and brittleness index of the epoxy resin sealant,as well as its tangential and normal shear strengths in conjunction with casing *** flow characteristics and sealing abilities of conventional cement and epoxy resin were comparatively analyzed in *** results showed that the application of a viscosity reducer facilitated control over the curing time of the epoxy resin,ranging from 1.5 to 6 h,and reduced the initial viscosity from 865.53 to 118.71 m Pa,*** mechanical properties of the epoxy resin initially increased with a rise in curing agent content before experiencing a minor *** epoxy resin containing 30%curing agent exhibited optimal mechanical *** a 14-day curing period,the epoxy resin's compressive strength reached81.37 MPa,2.12 times higher than that of cement,whereas the elastic modulus of cement was 2.99 times greater than that of the epoxy *** brittleness index of epoxy resin is only 3.42,demonstrating high flexibility and *** tangential and normal shear strengths of the epoxy resin exceeded those of cement by 3.17 and 2.82 times,*** a 0.5 mm-wide crack,the injection pressure of the epoxy resin remained below 0.075 MPa,indicating superior injection and flow ***,the injection pressure of cement surged dramatically to 2.61 MPa within 5 *** breakthrough pressure of0.5 PV epoxy resin reached 7.53 MPa,decreasing the crack's perme

关键词： Sustained casing pressure Epoxy resin sealant Curing agent Viscosity reducer Mechanical properties Crack sealing

Effects of different orthokeratology lens designs on slowing axial length elongation in children with myopia

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1843-1849页

作者： Hai-Long Ni Xiang Chen Du-Ya Chen pei-ke Hu Zhi-Yi Wu Eye Center the Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

AIM:To elucidate whether differences exist in the impact on retarding the elongation of axial length(AL)among children with myopia when utilizing orthokeratology(ortho-k)lenses employing the corneal refractive therapy(CRT)design versus those employing the vision shaping treatment(VST)***:This retrospective clinical trial aimed to collect and analyze AL data from individuals who wore ortho-k lenses for three years.A total of 654 subjects were enrolled and prescribed one of the three specific brands of ortho-k lenses:CRT,Euclid,and *** study’s primary focus was to compare the rates of AL elongation and myopic progression across these three brands of ortho-k ***:In the 3-year follow-up,the AL elongation exhibited variations of 0.73±0.36 mm in the CRT lens group,0.59±0.37 mm in the Euclid lens group,and 0.63±0.38 mm in the Mouldway lens group.A noteworthy disparity emerged between the CRT and Mouldway groups(P<0.01),as well as between the CRT and Euclid groups(P<0.001).Additionally,it was observed that 32.1%of participants who wore CRT lenses experienced a decelerated progression of myopia,in contrast to 47.2%in the Euclid group and 44.4%in the Mouldway *** analyses revealed a statistically significant distinction between the CRT and Euclid groups(P<0.01),and similarly,the CRT group demonstrated a statistically significant difference when compared to the Mouldway group(P<0.05).CONCLUSION:Ortho-k lenses represent a pragmatic strategy for mitigating the advancement of *** contradistinction to ortho-k lenses utilizing the CRT design,those employing the VST design exhibited a more favorable impact regarding retarding AL elongation.

关键词： myopia orthokeratology design axial length

Antisymmetric planar Hall effect in rutile oxide ﬁlms induced by the Lorentz force

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Science Bulletin 2024年第15期69卷 2362-2369页

作者： Yongwei Cui Zhaoqing Li Haoran Chen Yunzhuo Wu Yue Chen ke pei Tong Wu Nian Xie Renchao Che Xuepeng Qiu Yi Liu Zhe Yuan Yizheng Wu Department of Physics State Key Laboratory of Surface PhysicsFudan UniversityShanghai 200433China Institute for Nanoelectronic Devices and Quantum Computing Fudan UniversityShanghai 200433China Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan UniversityShanghai 200433China Center for Advanced Quantum Studies and Department of Physics Beijing Normal UniversityBeijing 100875China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438China Shanghai key Laboratory of Special Artiﬁcial Microstructure Materials and Technology School of Physics Science and EngineeringTongji UniversityShanghai 200092China Zhejiang Laboratory Hangzhou 311100China Shanghai Research Center for Quantum Sciences Shanghai 201315China Shanghai key Laboratory of Metasurfaces for Light Manipulation Fudan UniversityShanghai 200433China

The conventional Hall effect is linearly proportional to the field component or magnetization component perpendicular to a film. Despite the increasing theoretical proposals on the Hall effect to the in-plane field or magnetization in various special systems induced by the Berry curvature, such an unconventional Hall effect has only been experimentally reported in Weyl semimetals and in a heterodimensional superlattice. Here, we report an unambiguous experimental observation of the antisymmetric planar Hall effect(APHE) with respect to the in-plane magnetic field in centrosymmetric rutile RuO_(2) and IrO_(2) single-crystal films. The measured Hall resistivity is found to be linearly proportional to the component of the applied in-plane magnetic field along a particular crystal axis and to be independent of the current direction or temperature. Both the experimental observations and theoretical calculations confirm that the APHE in rutile oxide films is induced by the Lorentz force. Our findings can be generalized to ferromagnetic materials for the discovery of anomalous Hall effects and quantum anomalous Hall effects induced by in-plane magnetization. In addition to significantly expanding knowledge of the Hall effect, this work opens the door to explore new members in the Hall effect family.

关键词： Antisymmetric planar Hall effect Lorentz force Rutile oxide films Crystal symmetry

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STEAM教育理念下音乐教学改革实践探索

黑龙江高教研究 2024年第8期42卷 79-84页

作者：韩星冉陈珮珂华北水利水电大学河南郑州450046

随着教育创新不断推进,以STEAM为核心的教育理念已逐步成为引领学科教学改革的重要力量,围绕STEAM教育理念及其在音乐教育中的运用,对传统音乐教学存在的问题进行了深入分析,并提出了有针对性的改革目标。通过深入理解STEAM的内涵及其... 详细信息

随着教育创新不断推进,以STEAM为核心的教育理念已逐步成为引领学科教学改革的重要力量,围绕STEAM教育理念及其在音乐教育中的运用,对传统音乐教学存在的问题进行了深入分析,并提出了有针对性的改革目标。通过深入理解STEAM的内涵及其在教学中的实际应用,进一步明确了音乐教学改革的核心目的在于提升学生的综合素质和创新能力。通过教学改革实践,探索了STEAM教育理念与音乐教学改革相结合的可行性,其中,以河南豫剧为具体案例,详细阐述了实践路径。实践结果显示,基于STEAM教育理念的音乐教学改革能有效推动学科融合,提升学生的主动性和参与度。融入STEAM理念的教育实践不仅有助于解决现行音乐教学中的不足,还能引领教育改革朝着更具创新性和包容性的方向发展。

关键词：音乐教学 STEAM教育教学改革

基于UHPLC-Q-TOF-MS/MS探究山茱萸酒制前后与黄芪相关组分配伍对糖尿病肾病大鼠血浆代谢组学的影响

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中国中药杂志 2024年第13期49卷 3493-3504页

作者：陈忆菁朱慧刘鑫段煜裴科张巧宋沛祥蔡皓南京中医药大学药学院江苏南京210023 南京中医药大学国家教育部中药炮制规范化及标准化工程研究中心江苏南京210023 山西中医药大学中药与食品工程学院山西晋中030619

基于炮制和配伍探究山茱萸与黄芪相关组分对糖尿病肾病大鼠血浆代谢组学的影响。SD大鼠随机分为4组,用高脂饲料联合30 mg·kg^(-1)链脲佐菌素(STZ)诱导糖尿病肾病大鼠模型。采用HE、PAS和Masson染色对各组大鼠的肾脏组织切片进行病理学... 详细信息

基于炮制和配伍探究山茱萸与黄芪相关组分对糖尿病肾病大鼠血浆代谢组学的影响。SD大鼠随机分为4组,用高脂饲料联合30 mg·kg^(-1)链脲佐菌素(STZ)诱导糖尿病肾病大鼠模型。采用HE、PAS和Masson染色对各组大鼠的肾脏组织切片进行病理学观察。超高效液相色谱-四极杆飞行时间串联质谱(UHPLC-Q-TOF-MS/MS)代谢组学方法研究山茱萸酒制前后与黄芪相关组分配伍给药后对糖尿病肾病大鼠血浆代谢物的影响。给予药物治疗后,糖尿病肾病大鼠的肾组织损伤情况和间质胶原纤维沉积面积均有不同程度的改善(P<0.001)。血浆代谢组学的检测结果显示,在患病大鼠中共鉴定出71种与糖尿病肾病发病机制相关的生物标志物,主要涉及亚油酸代谢,咖啡因代谢,甘油磷脂代谢,苯丙氨酸、酪氨酸和色氨酸生物合成,花生四烯酸代谢,苯丙氨酸代谢,视黄醇代谢,乙醚脂质代谢。经药物干预后,其中有26种发生显著性回调,以精准炮制药对(P-CG_(5))疗效更好。该研究从血浆代谢组学的角度阐述了P-CG_(5)可从苯丙氨酸、酪氨酸和色氨酸生物合成,苯丙氨酸代谢,咖啡因代谢等途径改善糖尿病肾病的代谢紊乱,为山茱萸与黄芪相关组分配伍在中医临床上的应用提供了理论支撑和实验依据。

关键词：山茱萸黄芪酒制组分配伍糖尿病肾病血浆代谢组学

Analysis of Chemical Modification Mechanism and Rheological Properties of Polyphosphoric Acid Modified Asphalt

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Journal of Wuhan University of Technology(Materials Science) 2022年第5期37卷 876-884页

作者： WANG Lan pei ke LI Chao School of Civil Engineering Inner Mongolia University of TechnologyHohhot010051China Inner Mongolia Autonomous Region key Laboratory of Civil Engineering Structure and Mechanics Hohhot010051China

In order to study the chemical modification mechanism and rheological properties of polyphosphoric acid (PPA)-modified asphalt,asphalt modified with different PPA contents were characterized by four-component test,atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR).In the test,changes in asphalt chemical composition and colloidal structure were analyzed for different PPA contents,and infrared spectra were fitted with a Gaussian *** reaction mechanism of PPA and matrix asphalt was also *** on dynamic shear rheometer (DSR) test and bending beam rheometer (BBR) test,rheological index G~*/sinδ and S/m were used to evaluate the modification effect of PPA on *** results show that,with an increase in PPA content,both large and small honeycomb structures increased in the three-dimensional topography seen in the atomic force microscope (AFM).In a certain space range,some of the micelles in the asphalt are connected each other to form interlocking skeleton structures,and locally form dense spatial network *** added PPA does not chemically react with the functional groups in the functional-group area of the infrared spectra (3 100-2 750 cm^(-1),1 800-1 330 cm^(-1)),and the structure is very ***,there is an obvious new absorption peak below 1 330 cm^(-1) in the fingerprint area,that is,the chemical reaction between PPA and the matrix asphalt generates a new compound,inorganic *** spectra of PPA-modified asphalt with different contents were fitted by a Gaussian function,which makes up for the limitation that the absorption intensity information of each superimposed functional group cannot be obtained directly from the original infrared *** of this qualitative analysis were further verified by quantitative *** addition of PPA can effectively improve the high and low-temperature performance of asphalt,and the lower the temperature is in the negative temperature zone,

关键词： polyphosphoric acid-modified asphalt dynamic shear rheometer(DSR)test Fourier transform infrared spectroscopy(FTIR) chemical properties

基于指纹图谱及网络药理学的当归补血汤药材炮制前后差异质量标志物研究

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中国中药杂志 2024年第9期49卷 2451-2460页

作者：周洁李婕魏冰斌姜弢裴科张朔生孙琳山西中医药大学中药与食品工程学院山西晋中030619 山西中医药大学继续教育学院山西晋中030619

建立基于指纹图谱及网络药理学研究当归补血汤炮制前后的差异性质量标志物(Q-marker),并对筛选出的7种指标性成分进行定量分析,为炮制前后的当归补血汤质量评价提供实验依据。采用HPLC建立当归补血汤生品与炮制品的指纹图谱,利用多元统... 详细信息

建立基于指纹图谱及网络药理学研究当归补血汤炮制前后的差异性质量标志物(Q-marker),并对筛选出的7种指标性成分进行定量分析,为炮制前后的当归补血汤质量评价提供实验依据。采用HPLC建立当归补血汤生品与炮制品的指纹图谱,利用多元统计法对当归补血汤炮制前后特征图谱及共有峰面积进行分析,筛选出炮制前后的差异性特征成分,结合网络药理学构建其差异性成分的相关靶点及通路并对其成分进行定量分析。当归补血汤样品指纹图谱标定13个共有峰,并确认其中7个主要化学成分,其相似度均>0.911,进一步采用聚类分析、主成分分析、偏最小二乘法判别分析可明显区分生品与其炮制品,根据变量重要性投影(VIP)值筛选影响当归补血汤炮制前后的主要差异性成分1、2、6、13、5。将中药Q-marker“五原则”及网络药理学相结合,筛选出5-羟甲基糠醛、阿魏酸、毛蕊异黄酮葡萄糖苷、毛蕊异黄酮、藁本内酯、芒柄花素、洋川芎内酯Ⅰ为炮制前后的质量差异的标志性成分,定量分析结果显示,当归补血汤炮制后,洋川芎内酯Ⅰ、毛蕊异黄酮、芒柄花素、藁本内酯含量减少;毛蕊异黄酮葡萄糖苷、阿魏酸含量增加;同时产生了新的化学成分5-羟甲基糠醛。所建立的指纹图谱分析方法稳定可靠,并结合网络药理学与定量研究,筛选出差异性Q-marker,为当归补血汤炮制品的进一步研究提供实验依据。

关键词：当归补血汤炮制指纹图谱多元统计分析网络药理学质量标志物

从“温肺阳、护阴肤”理论出发论治慢性支气管炎

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中国实验方剂学杂志 2024年第15期30卷 215-223页

作者：鲁振刘庆银姚卫卫陶伟伟刘丽娜裴可南京中医药大学中西医结合学院南京210023 山东中医药大学康复医学院济南250355 德州市中医院山东德州253000

慢性支气管炎是一种常见的呼吸系统疾病,可归为中医学肺系疾病范畴,与肺的功能失调关系密切。肺阳为肺之阳气,是肺脏生理活动的原动力,具有温煦肺系、敷布肺津、宣散卫阳等生理功能,可经玄府流通气液布散于气道阴肤表面,发挥顾护、濡养... 详细信息

慢性支气管炎是一种常见的呼吸系统疾病,可归为中医学肺系疾病范畴,与肺的功能失调关系密切。肺阳为肺之阳气,是肺脏生理活动的原动力,具有温煦肺系、敷布肺津、宣散卫阳等生理功能,可经玄府流通气液布散于气道阴肤表面,发挥顾护、濡养作用。若卫阳失于顾护阴肤,或肺津不能濡养阴肤,导致气道阴肤的结构损伤,其肃清痰浊、布散肺津、抵御外邪等功能减退,痰浊留滞、阴肤失濡与外邪侵袭,均能耗伤肺阳、灼伤肺津,加剧阴肤失护的病理状态,形成恶性循环,终成肺阳虚损,导致慢性支气管炎发生。笔者从“阴肤失护”与“肺阳虚损”的内在联系切入,对慢性支气管炎病因病机进行解读,提出气道“阴肤失护”是慢性支气管炎发生的基本病因,在此基础上导致的“肺阳虚损”是慢性支气管炎的核心病机,并将微观辨指标与宏观辨证候结合,探讨其现代生物学基础。并在“温肺阳、护阴肤”理论的指导下,以现代药理学研究为基础,进一步探究单味中药及中药复方“温肺阳、护阴肤”调治慢性支气管炎的科学内涵,提出急性加重期祛邪护阴肤、缓解期扶正温肺阳的运用方法,以期为慢性支气管炎的早期防治拓展新思路。

关键词：慢性支气管炎阴肤失护肺阳虚损温肺阳护阴肤