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Effects of CH_(4)/CO_(2) multi-component gas on components and properties of tight oil during CO_(2) utilization and storage: Physical experiment and composition numerical simulation
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作者 Zhi-Hao Jia Ren-Yi Cao +5 位作者 Bin-Yu Wang Lin-Song Cheng Jin-Chong Zhou Bao-Biao Pu Fu-Guo Yin Ming Ma 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3478-3487,共10页
An essential technology of carbon capture, utilization and storage-enhanced oil recovery (CCUS-EOR) for tight oil reservoirs is CO_(2) huff-puff followed by associated produced gas reinjection. In this paper, the effe... An essential technology of carbon capture, utilization and storage-enhanced oil recovery (CCUS-EOR) for tight oil reservoirs is CO_(2) huff-puff followed by associated produced gas reinjection. In this paper, the effects of multi-component gas on the properties and components of tight oil are studied. First, the core displacement experiments using the CH_(4)/CO_(2) multi-component gas are conducted to determine the oil displacement efficiency under different CO_(2) and CH_(4) ratios. Then, a viscometer and a liquid density balance are used to investigate the change characteristics of oil viscosity and density after multi-component gas displacement with different CO_(2) and CH_(4) ratios. In addition, a laboratory scale numerical model is established to validate the experimental results. Finally, a composition model of multi-stage fractured horizontal well in tight oil reservoir considering nano-confinement effects is established to investigate the effects of multi-component gas on the components of produced dead oil and formation crude oil. The experimental results show that the oil displacement efficiency of multi-component gas displacement is greater than that of single-component gas displacement. The CH_(4) decreases the viscosity and density of light oil, while CO_(2) decreases the viscosity but increases the density. And the numerical simulation results show that CO_(2) extracts more heavy components from the liquid phase into the vapor phase, while CH_(4) extracts more light components from the liquid phase into the vapor phase during cyclic gas injection. The multi-component gas can extract both the light components and the heavy components from oil, and the balanced production of each component can be achieved by using multi-component gas huff-puff. 展开更多
关键词 multi-component gas Properties and components Core displacement experiment Nano-confinement numerical simulation CO_(2)utilization and storage
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Visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers
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作者 Feng Zhao Hongyu Ding +4 位作者 Ting Sun Chao Shen Zu-Li Wang Wei Wei Dong Yi 《Chinese Chemical Letters》 2026年第2期206-217,共12页
Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable ... Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable strategy for constructing new carbon-oxygen bonds.In comparison with traditional thermal or metal-mediated carbene transfer reactions,visible-light-promoted multi-component reaction strategy provides a mild and eco-friendly approach to access densely functionalized molecules.Recently,visible-light-induced multi-component carbene transfer reactions of diazo compounds have been rapidly developed and attracted a great deal of research interest of chemists owing to their advantages of simple operation,mild condition,high atom economy and rich structural diversity.This paper summarizes the recent research progress on the visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers with various nucleophiles.The reaction patterns of different nucleophiles and their corresponding mechanism are described in this review.The future research direction and challenges in this area are also discussed. 展开更多
关键词 VISIBLE-LIGHT multi-component reaction Carbene insertion Diazo compounds Ring-opening reaction
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绝经后2型糖尿病患者血清lncRNA GAS5表达与骨密度的关系
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作者 王龙 谈波宇 +2 位作者 王姣 刘芬芬 丁怡 《中国骨质疏松杂志》 北大核心 2026年第3期387-392,417,共7页
目的探究绝经后2型糖尿病(type 2 diabetes mellitus,T2DM)患者血清中长链非编码RNA(long non-coding RNA,LncRNA)生长停滞特异性转录本5(growth arrest-specific transcript 5,GAS5)的表达水平与骨密度(Bone mineral density,BMD)之间... 目的探究绝经后2型糖尿病(type 2 diabetes mellitus,T2DM)患者血清中长链非编码RNA(long non-coding RNA,LncRNA)生长停滞特异性转录本5(growth arrest-specific transcript 5,GAS5)的表达水平与骨密度(Bone mineral density,BMD)之间的关联。方法纳入210名绝经后T2DM患者,根据BMD状况分为正常骨量组(58例)、骨量减少组(71例)和骨质疏松组(81例)。采用实时定量PCR(quantitative real-time polymerase chain reaction,qRT-PCR)技术检测血清中lncRNA GAS5的表达水平,Pearson相关性分析评估lncRNA GAS5与BMD之间的相关性。多因素Logistic回归分析识别影响绝经后T2DM患者骨质疏松发生的因素,受试者工作特征曲线(receiver operating characteristic curve,ROC)评估lncRNA GAS5在预测骨质疏松中的价值。结果与正常骨量组相比,骨量减少组和骨质疏松组患者的年龄、绝经年数、糖化血红蛋白(glycosylated hemoglobin A1C,HbA1c)、空腹血糖(fasting plasma glucose,FPG)、I型前胶原氨基末端前肽(type I procollagen amino-terminal propeptide,PINP)以及CTX水平均升高,且骨质疏松组均高于骨量减少组(P<0.05)。与正常骨量组相比,骨量减少组和骨质疏松组的25羟维生素D 3[25-hydroxyvitamin D 3,25(OH)D 3]、L 1~4 BMD、股骨颈BMD、全髋BMD、以及lncRNA GAS5水平均降低,且骨质疏松组均低于骨量减少组(P<0.05)。L 1~4 BMD、股骨颈BMD、全髋BMD与年龄、绝经年数、HbA1c、FPG、PINP呈负相关,而与25(OH)D 3、lncRNA GAS5呈正相关(P<0.05)。lncRNA GAS5与CTX呈负相关(P<0.05)。高龄、长绝经年数、高PINP水平、低25(OH)D 3水平和低lncRNA GAS5水平是绝经后2型糖尿病患者发生骨质疏松的危险因素。血清lncRNA GAS5在预测绝经后2型糖尿病患者骨质疏松发生时的截断值为0.74,AUC值为0.934,灵敏度为92.6%,特异性为81.4%。结论绝经后T2DM患者中lncRNA GAS5低表达与BMD下降相关,是骨质疏松发生的危险因素,且对骨质疏松有较好预测能力。 展开更多
关键词 lncRNA gas5 骨密度 2型糖尿病 绝经后女性
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Fretting Wear Behavior of Medium Carbon Steel Modified by Low Temperature Gas Multi-component Thermo-chemical Treatment 被引量:3
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作者 LUO Jun ZHENG Jianfeng +2 位作者 PENG Jinfang HE Liping ZHU Minhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第3期288-296,共9页
The introduction of surface engineering is expected to be an effective strategy against fretting damage.A large number of studies show that the low gas multi-component(such as carbon,nitrogen,sulphur and oxygen,etc)th... The introduction of surface engineering is expected to be an effective strategy against fretting damage.A large number of studies show that the low gas multi-component(such as carbon,nitrogen,sulphur and oxygen,etc)thermo-chemical treatment(LTGMTT)can overcome the brittleness of nitriding process,and upgrade the surface hardness and improve the wear resistance and fatigue properties of the work-pieces significantly.However,there are few reports on the anti-fretting properties of the LTGMTT modified layer up to now,which limits the applications of fretting.So this paper discusses the fretting wear behavior of modified layer on the surface of LZ50(0.48%C)steel prepared by low temperature gas multi-component thermo-chemical treatment(LTGMTT)technology.The fretting wear tests of the modified layer flat specimens and its substrate(LZ50 steel)against 52100 steel balls with diameter of 40 mm are carried out under normal load of 150 N and displacement amplitudes varied from 2μm to 40μm.Characterization of the modified layer and dynamic analyses in combination with microscopic examinations were performed through the means of scanning electron microscope(SEM),optical microscope(OM),X-ray diffraction(XRD)and surface profilometer.The experimental results showed that the modified layer with a total thickness of 60μm was consisted of three parts,i.e.,loose layer,compound layer and diffusion layer.Compared with the substrate,the range of the mixed fretting regime(MFR)of the LTGMTT modified layer diminished,and the slip regime(SR)of the modified layer shifted to the direction of smaller displacement amplitude.The coefficient of friction(COF)of the modified layer was lower than that of the substrate in the initial stage.For the modified layer,the damage in partial slip regime(PSR)was very slight.The fretting wear mechanism of the modified layer both in MFR and SR was abrasive wear and delamination.The modified layer presented better wear resistance than the substrate in PSR and MFR;however,in SR,the wear resistance of the modified layer decreased with the increase of the displacement amplitudes.The experimental results can provide some experimental bases for promoting industrial application of LTGMTT modified layer in anti-fretting wear. 展开更多
关键词 fretting wear fretting regimes low temperature gas multi-component thermo-chemical treatment(LTGMTT) modified layer medium carbon steel
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Predicting gas-bearing distribution using DNN based on multi-component seismic data: Quality evaluation using structural and fracture factors 被引量:4
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作者 Kai Zhang Nian-Tian Lin +3 位作者 Jiu-Qiang Yang Zhi-Wei Jin Gui-Hua Li Ren-Wei Ding 《Petroleum Science》 SCIE CAS CSCD 2022年第4期1566-1581,共16页
The tight-fractured gas reservoir of the Upper Triassic Xujiahe Formation in the Western Sichuan Depression has low porosity and permeability. This study presents a DNN-based method for identifying gas-bearing strata ... The tight-fractured gas reservoir of the Upper Triassic Xujiahe Formation in the Western Sichuan Depression has low porosity and permeability. This study presents a DNN-based method for identifying gas-bearing strata in tight sandstone. First, multi-component composite seismic attributes are obtained.The strong nonlinear relationships between multi-component composite attributes and gas-bearing reservoirs can be constrained through a DNN. Therefore, we identify and predict the gas-bearing strata using a DNN. Then, sample data are fed into the DNN for training and testing. After optimized network parameters are determined by the performance curves and empirical formulas, the best deep learning gas-bearing prediction model is determined. The composite seismic attributes can then be fed into the model to extrapolate the hydrocarbon-bearing characteristics from known drilling areas to the entire region for predicting the gas reservoir distribution. Finally, we assess the proposed method in terms of the structure and fracture characteristics and predict favorable exploration areas for identifying gas reservoirs. 展开更多
关键词 multi-component seismic exploration Tight sandstone gas reservoir prediction Deep neural network(DNN) Reservoir quality evaluation Fracture prediction Structural characteristics
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Segregation modes,characteristics,and mechanisms of multi-component lignite in a vibrated gas-fluidized bed 被引量:2
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作者 Su Ding Luo Zhenfu +1 位作者 Lei Lingyan Zhao Yuemin 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第2期251-258,共8页
The segregation modes and characteristics of 1-6 mm multi-component lignite were studied in a microporous, vibrated, gas-fluidized bed of Φ110 mm ×400 mm. The effects of particle density and size, vibration freq... The segregation modes and characteristics of 1-6 mm multi-component lignite were studied in a microporous, vibrated, gas-fluidized bed of Φ110 mm ×400 mm. The effects of particle density and size, vibration frequency and amplitude, and gas velocity on these characteristics were considered. The average size, average density, size deviation coefficient, and density deviation coefficient were used to identify lignite size and density. The separation efficiency was adopted to evaluate the segregation performance,and the segregation mechanisms were explored. The results show that ε(size,max) of heterogeneous multisize-component lignite with K_(size) = 65% reaches 80% at f= 20 Hz, A = 5 mm, and N =(1,3). ε_(density,max) Of heterogeneous multi-density-component lignite with K_(density)= 25% reaches 50% at f = 15 Hz, A = 5 mm,and N =(1,1.5). The density segregations of 1-3 and 3-6 mm multi-component mixtures are remarkable,ε_(density,max)= 42% and 31% at f= 14 and 16 Hz, and A = 3 and 5 mm, respectively. The size segregation of 1-6 mm multi-component mixture is prominent and ε_(size,max)= 55% at f= 15 Hz, A = 5 mm. The mediumsized mixture with a narrow size distribution at low frequency is favorable for density segregation,and a mixture with a wider size distribution at high frequency is most favorable for size segregation.Precise control of gas flow and vibration as well as optimal design of the fluidized bed can improve the performance of segregation in the vibrated gas-fluidized bed. 展开更多
关键词 Dry-beneficiation multi-component LIGNITE SEGREGATION mode Degree of HOMOGENEITY
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Study on multi-component combustible gas explosive characteristics of high gas mine 被引量:2
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作者 周西华 王继仁 +2 位作者 李昕 李诚玉 胡春岩 《Journal of Coal Science & Engineering(China)》 2008年第4期538-541,共4页
Studied on multi-component combustible gas,methane mainly,explosion char- acteristics of high gas mine,obtained the rules of gas explosive limit that influenced by environment temperature,pressure,concentration of oxy... Studied on multi-component combustible gas,methane mainly,explosion char- acteristics of high gas mine,obtained the rules of gas explosive limit that influenced by environment temperature,pressure,concentration of oxygen,other combustible gas,coal dust,energy of fire source,and the inert gas,proposed a new method of divide gas explo- sive triangle partition,and gave new partition linear equations.The gas explosive triangle and its new partition has important directive significance in distinguishing if the fire area has a gas explosion when sealing or opening fire area,or fire extinguishing in sealed fire area,and judging if there will be a gas explosion or other trend while fire extinguishing with inert gas. 展开更多
关键词 gas explosion explosive characteristics gas explosive limit
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电针经Gas6/MerTK通路调节FD大鼠胞葬作用减轻十二指肠低度炎症的机制研究
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作者 韩永丽 姚卫杰 +6 位作者 张宝霞 陈奕臻 智沐君 郑雪 王庆波 康朝霞 张红星 《时珍国医国药》 北大核心 2026年第3期564-570,共7页
目的基于Gas6/MerTK胞葬通路探讨电针对功能性消化不良(FD)大鼠十二指肠低度炎症和胃肠动力的影响及作用机制。方法健康SD大鼠随机分为空白组、模型组、电针+Gas6过表达组、电针+Gas6抑制剂组和电针组,分别给予后3组相应的Gas6腺病毒滴... 目的基于Gas6/MerTK胞葬通路探讨电针对功能性消化不良(FD)大鼠十二指肠低度炎症和胃肠动力的影响及作用机制。方法健康SD大鼠随机分为空白组、模型组、电针+Gas6过表达组、电针+Gas6抑制剂组和电针组,分别给予后3组相应的Gas6腺病毒滴液、Gas6抑制剂和电针处理。ELISA法检测十二指肠组织中促炎细胞因子和抗炎细胞因子的含量;WB法检测十二指肠组织中Gas6、MerTK和胞葬通路相关指标(SIRPα、Axl、CD47、MFGE8、Pros)的蛋白表达变化。结果与空白组比较,模型组大鼠十二指肠IL-17、IFN-γ表达上调(P<0.001),IL-4、TGF-β表达降低(P<0.001),Gas6、MerTK表达降低(P<0.001)和胞葬作用减轻,胞葬通路相关指标的蛋白表达降低;与模型组比较,电针+Gas6过表达组和电针组IL-17、IFN-γ表达降低(P<0.05),IL-4、TGF-β升高(P<0.05),胞葬作用更明显,Gas6、MerTK和胞葬通路相关指标的蛋白表达升高(P<0.05);与电针组比较,电针+Gas6过表达组IL-17、IFN-γ表达降低(P<0.001),IL-4、TGF-β升高(P<0.001),胞葬作用稍增强,Gas6、MerTK和胞葬通路相关指标的蛋白表达升高(P<0.001);电针+Gas6抑制剂组的趋势与之相反。结论电针可能通过Gas6/MerTK通路降低FD大鼠十二指肠低度炎症,增强胞葬作用,促进胃肠动力。 展开更多
关键词 电针 十二指肠 胞葬 gas6/MerTK 功能性消化不良 低度炎症 胃肠动力
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Research on Multi-Component Gas Optical Detection System Based on Conjugated Interferometer 被引量:1
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作者 Xin GUI Yuheng TONG +2 位作者 Honghai WANG Haihu YU Zhengying LI 《Photonic Sensors》 SCIE EI CAS CSCD 2017年第3期261-269,共9页
An optical multi-component gas detection system based on the conjugated interferometer (CI) is proposed and experimentally demonstrated. It can realize the concentration detection of mixture gas in the environment. ... An optical multi-component gas detection system based on the conjugated interferometer (CI) is proposed and experimentally demonstrated. It can realize the concentration detection of mixture gas in the environment. The CI can transform the absorption spectrum of the target gases to a conjugated emission spectrum, when combining the CI with the broadband light source, the spectrum of output light matches well with the absorption spectrum of target gases. The CI design for different target gases can be achieved by replacing the kind of target absorbing gas in the CI filter. The traditional fiber gas sensor system requires multiple light sources for detection when there are several kinds of gases, and this problem has been solved by using the CI filter combined with the broadband light source. The experimental results show that the system can detect the concentration of multi-component gases, which are mixed with C2H2 and NH3. Experimental results also show a good concentration sensing linearity. 展开更多
关键词 gas conjugated interference filter gas sensing spectral absorption
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安石榴苷调节Gas6/Axl通路介导的免疫反应对乳腺癌细胞活性的影响
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作者 王树人 杨柳 王琦 《中国免疫学杂志》 北大核心 2026年第2期361-366,共6页
目的:探究安石榴苷(PN)调节Gas6/Axl通路介导的免疫反应对乳腺癌细胞活性的影响。方法:采用12.5~400μmol/L PN处理人乳腺癌细胞MCF-7,检测细胞增殖活性,筛选PN实验浓度。将MCF-7细胞随机分为Control组、PN低、中、高浓度组(PN-L组、PN-... 目的:探究安石榴苷(PN)调节Gas6/Axl通路介导的免疫反应对乳腺癌细胞活性的影响。方法:采用12.5~400μmol/L PN处理人乳腺癌细胞MCF-7,检测细胞增殖活性,筛选PN实验浓度。将MCF-7细胞随机分为Control组、PN低、中、高浓度组(PN-L组、PN-M组、PN-H组)、高浓度PN+Gas6重组蛋白组(Gas6重组蛋白组);检测MCF-7细胞的增殖、迁移、侵袭能力;检测MCF-7细胞上清液中炎症水平;Western blot检测上皮间质转化(EMT)和相关蛋白表达。结果:通过检测MCF-7细胞的增殖活性,筛选出50、100、200μmol/L PN作为本研究中的处理浓度。与Control组比较,PN-L、PN-M、PN-H组MCF-7细胞克隆形成数、划痕愈合率、细胞侵袭数量、IL-6表达水平降低,IL-10表达水平升高;CDK1、MMP-2、MMP-9、N-Cadherin、Vimentin、Gas6、Axl蛋白表达降低,E-Cadherin蛋白表达升高(P<0.05);与PN-H组相比,Gas6重组蛋白组克隆形成数、划痕愈合率、细胞侵袭数量、IL-6表达水平上升,CDK1、MMP-2、MMP-9、N-Cadherin、Vimentin、Gas6、Axl蛋白表达升高,IL-10表达水平降低,E-Cadherin蛋白表达降低(P<0.05)。结论:PN可能通过抑制Gas6/Axl通路介导的免疫反应抑制乳腺癌细胞的增殖、迁移、侵袭活性。 展开更多
关键词 乳腺癌 安石榴苷 gas6/Axl通路 免疫反应 细胞活性
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抗阻运动经Gas1锚定蛋白干预老年肌少症小鼠肌肉干细胞自我更新的作用
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作者 曲波 黄盈 +4 位作者 邓长青 卢蕊 夏雨 张燕 丁海丽 《中国运动医学杂志》 北大核心 2026年第2期122-132,共11页
目的:探讨生长特异性阻滞基因1(growth arrest-specific 1,Gas1)在抗阻运动改善老年肌少症小鼠肌肉干细胞(muscle stem cells,MuSCs)自我更新中的作用,为运动疗法在临床骨骼肌疾病中的应用提供理论依据。方法:选取32周龄雄性快速衰老小... 目的:探讨生长特异性阻滞基因1(growth arrest-specific 1,Gas1)在抗阻运动改善老年肌少症小鼠肌肉干细胞(muscle stem cells,MuSCs)自我更新中的作用,为运动疗法在临床骨骼肌疾病中的应用提供理论依据。方法:选取32周龄雄性快速衰老小鼠(senescence accelerated mouse prone 8,SAMP8)16只,随机分为模型组(model group,M组)和抗阻运动组(resistance group,R组),另选取8只同龄雄性抗衰老小鼠(senescence accelerated mouse resistant 1,SAMR1)作为年轻对照组(control group,C组)。C组、M组常规饲养,R组小鼠进行8周尾部负重式抗阻运动。每周对小鼠进行1次行为学检测;干预结束后,测量小鼠腓肠肌/体重,反映相对肌肉质量;采用透射电镜观察肌纤维超微结构、苏木精-伊红染色法(HE)观测肌纤维形态并测算肌纤维横截面积;酶联免疫吸附法(ELISA)检测小鼠骨骼肌中胶质细胞源性营养因子(glial cell line-derived neurotrophic factors,GDNF)蛋白含量;Western Blotting检测骨骼肌中配对盒基因7(paired box 7,Pax7)、生肌调节因子(myoblast determination protein 1,MyoD)、肌细胞生成素(Myogenin)、Gas1、磷脂酰肌醇3-激酶(phosphatidylinositol 3-kinase,PI3K)、蛋白激酶B(protein kinase B,AKT)、pAKT、肌肉萎缩盒F基因(Atrogin1)及肌肉特异性环指蛋白-1(muscle ring finger-1,MuRF1)的蛋白表达;免疫荧光双标法观测Pax7与MyoD、GDNF的共定位表达情况。结果:(1)行为学指标:(1)干预前,SAMP8小鼠较SAMR1小鼠相对抓力较低(P<0.05)、转棒时长更低(P<0.01);(2)干预后,R组小鼠较M组相对抓力、转棒时长均较高(P<0.01)。(2)形态学指标:(1)透射电镜与HE结果显示:C组小鼠骨骼肌肌纤维分布均匀、紧致,Z线清晰整齐;而M组则Z线杂乱、肌纤维分布杂乱松散;R组小鼠肌纤维稍显杂乱,肌丝走行相对清晰,细胞器相对完整。(2)与C组相比,M组小鼠肌肉横截面积和相对肌肉质量均较低(P<0.01),R组则无显著性差异;运动干预后与M组相比,R组小鼠肌纤维横截面积和相对肌肉质量均较高。(3)MuSCs自我更新的变化:与C组相比,M组Pax7和MyoD蛋白表达较低(P<0.01,P<0.05),Myogenin蛋白表达无显著性差异,处于静息态(Pax7+/MyoD-)和细胞周期(Pax7+/MyoD+)的MuSCs数量较低(P<0.01,P<0.05);抗阻运动后R组Pax7、MyoD和Myogenin蛋白表达均较高(P<0.05,P<0.01),静息态与细胞周期的MuSCs数量较M组更高(P<0.01)。(4)GDNF-Gas1及下游信号通路表达变化:与C组相比,M组骨骼肌中GDNF、PI3K、pAKT/AKT表达较低(P<0.01),而Gas1、Atrogin1及MuRF1表达较高(P<0.05,P<0.01),同时Pax7与GDNF共定位表达较低;抗阻运动干预后,与M组相比,R组骨骼肌中GDNF、PI3K、pAKT/AKT较高(P<0.01),Gas1、Atrogin1和MuRF1表达则较低(P<0.05,P<0.01),Pax7与GDNF共定位表达则更高。结论:8周抗阻运动能够改善老年肌少症小鼠的骨骼肌力量、质量和功能,其可能通过上调GDNF表达,抑制Gas1对细胞增殖的负向调控以提高PI3K-AKT信号通路活性,促进MuSCs自我更新及抑制萎缩因子表达从而改善肌少症。 展开更多
关键词 抗阻运动 肌少症 MuSCs自我更新 SAMP8小鼠 gas1
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Application of multi-component joint inversion in oil and gas exploration:A case study of reservoir and gas saturation prediction of the Xujiahe formation in the PLN area of the central Sichuan Basin
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作者 Wang Dong He Zhen-Hua +4 位作者 Wang Xu-Ben Li Le Yang Hai-Tao Fu Zhi-Guo Wang Hong-Yan 《Applied Geophysics》 SCIE CSCD 2020年第5期879-889,905,共12页
Multi-component seismic exploration is an important technique in the utilization of P-waves and converted S-waves for oil and gas exploration.It has unique advantages in the structural imaging of gas zones,reservoir p... Multi-component seismic exploration is an important technique in the utilization of P-waves and converted S-waves for oil and gas exploration.It has unique advantages in the structural imaging of gas zones,reservoir prediction,lithology,and gas-water identifi cation,and the development direction and degree of fractures.Multi-component joint inversion is one of the most important steps in multi-component exploration.In this paper,starting from the basic principle of multi-component joint inversion,the diff erences between the method and single P-wave inversion are introduced.Next,the technique is applied to the PLN area of the Sichuan Basin,and the P-wave impedance,S-wave impedance,and density are obtained based on multi-component joint inversion.Through the velocity and lithology,porosity,and gas saturation fi tting formulas,prediction results are calculated,and the results are analyzed.Finally,multi-component joint inversion and single P-wave inversion are compared in eff ective reservoir prediction.The results show that multi-component joint inversion increases the constraints on the inversion conditions,reduces the multi-solution of a single P-wave inversion,and is more objective and reliable for the identification of reservoirs,effectively improving the accuracy of oil and gas reservoir prediction and development. 展开更多
关键词 multi-component joint inversion lithology identifi cation POROSITY gas saturation reservoir prediction
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Multi-component decompositions,linear superpositions,and new nonlinear integrable coupled KdV-type systems
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作者 Xiazhi Hao S Y Lou 《Communications in Theoretical Physics》 2025年第2期1-12,共12页
In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrabilit... In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrability.By focusing on single-component decompositions within the potential BKP hierarchy,it has been observed that specific linear superpositions of decomposition solutions remain consistent with the underlying equations.Moreover,through the implementation of multi-component decompositions within the potential BKP hierarchy,successful endeavors have been undertaken to formulate linear superposition solutions and novel coupled Kd V-type systems that resist decoupling via alterations in dependent variables. 展开更多
关键词 integrable system single-component decomposition multi-component decomposition linear superposition integrable coupled KdV-type system
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A facile high-efficiency preparation strategy for Al-containing multi-component boride microcrystals with superior comprehensive performance
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作者 Yong Fan Jinfeng Nie +7 位作者 Zhigang Ding Yujing Zhang Xiang Chen Wei Liu Sen Yang Sida Liu Xiangfa Liu Yonghao Zhao 《Journal of Materials Science & Technology》 2025年第1期190-203,共14页
Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current method... Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current methods,however,are complicated and time-consuming,the mass production remains a chal-lenge.Herein,we proposed a new high-efficiency strategy for synthesis of MMB_(2)using molten aluminum as the medium for the first time.The prepared Al-containing multi-component borides(TiZrHfNbTa)B_(2)microcrystals had a homogeneous composition with a hexagonal AlB_(2)structure and ultra-high hardness value of∼35.3 GPa,which was much higher than data reported in the literature and the rule of mix-ture estimations.Furthermore,combined with the First-principles calculation results,we found that the Poisson’s ratio(v)values exhibit a clearly ascending trend from 0.17 at VEC=3.5 to 0.18 at VEC=3.4,then to 0.201 at VEC=3.2 with the increasing of Al content.This indicates that the intrinsic toughness of multi-component boride microcrystals is obviously enhanced by the trace-doped Al elements.Besides,the fabricated Al-containing multi-component boride microcrystals have superior oxidation activation en-ergy and structural stability.The enhanced oxidation resistance is mainly attributed to the formation of a protective Al2 O3 oxide layer and the lattice distortion,both of which lead to sluggish diffusion of O_(2).These findings propose a new unexplored avenue for the fabrication of MMB_(2)materials with supe-rior comprehensive performance including ultra-hardness and intrinsically improved thermo-mechanical properties. 展开更多
关键词 multi-component borides First-principles calculations Crystal growth Mechanical properties Oxidation behavior
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Uncovering the hardening mechanism of multi-component carbide ceramics based on the coupling effect of covalent bond enhancement and lattice distortion
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作者 Qingyi Kong Qinchen Liu +7 位作者 Lei Chen Sijia Huo Kunxuan Li Mingxuan Mao WeiWei Sun Yujin Wang Suk-Joong L.Kang Yu Zhou 《Journal of Materials Science & Technology》 2025年第31期102-112,共11页
The hardening mechanism of multi-component carbide ceramic has been investigated in detail through a combination of experiments,first-principles calculations,and ab initio molecular dynamics(AIMD).Eight dense carbide ... The hardening mechanism of multi-component carbide ceramic has been investigated in detail through a combination of experiments,first-principles calculations,and ab initio molecular dynamics(AIMD).Eight dense carbide ceramics were prepared by spark plasma sintering.Compulsorily,all the multi-component carbide samples have similar carbon content,grain size,and uniform compositional distribution by optimizing the sintering process and adjusting the initial raw materials.Hence the interference of other factors on the hardness of multi-component carbide ceramics is minimized.The effects of changes in the elemental species on the lattice distortion,bond strength,bonding properties,and electronic structure of multi-component carbide ceramics were thoroughly analyzed.These results show that the hardening of multi-component carbide ceramic can be attributed to the coupling of solid solution strengthening caused by lattice distortion and covalent bond strengthening.Besides,the“host lattice”of multi-component carbide ceramics is defined based on the concept of supporting lattice.The present work is of great significance for a deeper understanding of the hardening mechanism of multi-component carbide ceramics and the design of superhard multi-component carbides. 展开更多
关键词 multi-component ceramics Mechanical properties Hardening mechanism First principle calculation Ab initio molecular dynamics
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Photocatalytic multi-component synthesis of ester-containing quinoxalin-2(1H)-ones using water as the hydrogen donor
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作者 Qiang Feng Jindong Hao +3 位作者 Ya Hu Rong Fu Wei Wei Dong Yi 《Chinese Chemical Letters》 2025年第6期484-488,共5页
A convenient photocatalytic multi-component reaction of alkenes,quinoxalin-2(1H)-ones,and diazo compounds has been developed in the presence of water.A number of ester-containing quinoxalin-2(1H)-ones could be efficie... A convenient photocatalytic multi-component reaction of alkenes,quinoxalin-2(1H)-ones,and diazo compounds has been developed in the presence of water.A number of ester-containing quinoxalin-2(1H)-ones could be efficiently obtained in moderate to good yields at room temperature.This metal-free visiblelight-driven tandem reaction was conducted through proton-coupled electron transfer(PCET)process using water as the hydrogen donor and 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene(4CzIPN)as the photocatalyst. 展开更多
关键词 PHOTOCATALYTIC multi-component synthesis Diazo compounds Radical reaction Quinoxalin-2(1H)-ones
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Fast algorithm of borehole correction library construction for multi-component array induction tool in deviated boreholes
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作者 Ya-Zhou Wang Hong-Nian Wang +2 位作者 Lei Yu Yan Bai Shou-Wen Yang 《Petroleum Science》 2025年第12期5034-5046,共13页
The construction of a borehole correction library for the multi-component array induction tool in deviated boreholes involves extensive 3D forward modeling and typically requires significant computational resources.To... The construction of a borehole correction library for the multi-component array induction tool in deviated boreholes involves extensive 3D forward modeling and typically requires significant computational resources.To address this challenge,this paper proposes an efficient algorithm for the library construction based on the 3D finite volume method(FVM)and contraction high-order Born approximation(CHBA).First,the electromagnetic(EM)field solution region is divided into two symmetric subregions based on the symmetry of the correction library model and the EM field.Numerical solution on a single subregion,combined with the symmetry boundary extension technique,enhances the efficiency of the 3D numerical simulation.Second,three reference mud conductivities are selected based on the mud conductivity range,and the CHBA is applied to calculate the EM responses at all mud conductivity nodes rapidly.Third,the number of forward simulation operations is further reduced by exploiting the principle that models with different frequencies and different formation conductivities have equivalent EM responses.Numerical experiments demonstrate the correctness and feasibility of the proposed algorithm.Compared to conventional 3D modeling,the proposed algorithm achieves approximately a 20-fold speedup in library construction,effectively reducing computational resources and time consumption. 展开更多
关键词 multi-component array induction logging Borehole correction library 3D finite volume method Contraction high-order Born approximation
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High resistance SO_(2) adsorbent of Fe-Ce-La oxides@Si-Al carrier for arsenic capture from middle-low-temperature flue gas
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作者 WEN Hangyu HOU Shuyang +2 位作者 WANG Kai ZHANG Kaihua ZHANG Kai Beijing 《燃料化学学报(中英文)》 北大核心 2026年第2期166-179,共14页
It is crucial to develop arsenic removal adsorbents with strong sulfur resistance under middle-low-temperature flue gas conditions(<400℃).In this work,five Fe-Ce-La oxides were prepared by co-precipitation method,... It is crucial to develop arsenic removal adsorbents with strong sulfur resistance under middle-low-temperature flue gas conditions(<400℃).In this work,five Fe-Ce-La oxides were prepared by co-precipitation method,and FeCeLaO/SiO_(2)-Al_(2)O_(3) composite adsorbents were prepared by coupling fly ash-based Si-Al carriers.The active components Fe-Ce-La oxides and Si-Al carriers were characterized by TPD,TG,XRF,BET and XPS,respectively.The effects of temperature,Si/Al ratio and FeCeLaO loading rate on the sulfur resistance were investigated.Results show that the SO_(2) promotes the arsenic removal of Fe_(2)O_(3),CeLaO and FeCeLaO.At 400℃,the arsenic removal efficiencies of the three oxides increase from 45.3%,72.5% and 81.3% without SO_(2) to 62.6%,80.5%and 91.0%,respectively.The SO_(2) inhibits the arsenic removal of La_(2)O_(2)CO_(3) and FeLaO,and the inhibition effect is pronounced at high temperatures.The sulfur poisoning resistance of Si-Al carriers increases with the increase of Si/Al ratio.When the Si/Al ratio is increased to 9.74,the arsenic removal efficiency in the SO_(2) environment is 13.9% higher than that in the absence of SO_(2).Introducing FeCeLaO active components is beneficial for enhancing the SO_(2) poisoning resistance of Si-Al carriers.The strong sulfur resistance of the FeCeLaO/SiO_(2)-Al_(2)O_(3) composite adsorbent results from multiple factors:protective effects of Ce on Fe,La and Al;sulfation-induced generation of Ce^(3+)and surface-adsorbed oxygen;and strong surface acidity of SiO_(2). 展开更多
关键词 arsenic removal sulfur resistance flue gas Fe-Ce-La oxides fly ash
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Cavity ring-down spectroscopy CO gas sensor integrating principal component analysis with savitzky-golay filtering
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作者 GUO Zi-long SHI Cheng-rui +4 位作者 DONG Yuan-yuan ZHANG Lei SUN Xiao-yuan SUN Jing-jing ZHOU Sheng 《中国光学(中英文)》 北大核心 2026年第1期179-189,共11页
The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recogni... The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recognized to be limited at data boundaries and high frequencies,which can significantly reduce the signal-to-noise ratio(SNR).To solve this problem,a novel method synergistically integrating Principal Component Analysis(PCA)with SG filtering is proposed in this paper.This approach avoids the is-sue of excessive smoothing associated with larger window sizes.The proposed PCA-SG filtering algorithm was applied to a CO gas sensing system based on Cavity Ring-Down Spectroscopy(CRDS).The perform-ance of the PCA-SG filtering algorithm is demonstrated through comparison with Moving Average Filtering(MAF),Wavelet Transformation(WT),Kalman Filtering(KF),and the SG filter.The results demonstrate that the proposed algorithm exhibits superior noise reduction capabilities compared to the other algorithms evaluated.The SNR of the ring-down signal was improved from 11.8612 dB to 29.0913 dB,and the stand-ard deviation of the extracted ring-down time constant was reduced from 0.037μs to 0.018μs.These results confirm that the proposed PCA-SG filtering algorithm effectively improves the smoothness of the ring-down curve data,demonstrating its feasibility. 展开更多
关键词 cavity ring-down spectroscopy CO gas sensor principal component analysis Savitzky-Golay filter
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Natural Gas Industry B
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《天然气工业》 北大核心 2026年第1期F0003-F0003,共1页
Natural Gas Industry B创刊于2014年,是天然气工业杂志社与KeAi公司合作出版的国际OA期刊,在爱思唯尔旗下的Science Direct平台上双月出版。论文聚焦天然气、氢气、氦气、地热等地质能源,涵盖地质勘探、气藏开发、工程技术、储运利用... Natural Gas Industry B创刊于2014年,是天然气工业杂志社与KeAi公司合作出版的国际OA期刊,在爱思唯尔旗下的Science Direct平台上双月出版。论文聚焦天然气、氢气、氦气、地热等地质能源,涵盖地质勘探、气藏开发、工程技术、储运利用、净化化工、产业趋势等专业方向。期刊服务全球天然气产业,并积极推动能源行业碳减排和低碳转型的发展。 展开更多
关键词 Natural gas Industry B
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