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燃烧热测定实验的课程思政设计
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作者 肖厚贞 王明玉 +3 位作者 刘用 劳邦盛 卢凌彬 庾名槐 《大学化学》 CAS 2024年第2期7-13,共7页
采用线上+线下混合式教学模式开展教学改革,将热带作物材料和产品,包括椰肉、椰子油和油棕果实引入物理化学经典实验项目——燃烧热的测定。通过本实验,学生不仅掌握了块状固体、粉末状固体、液体三种不同外貌样品燃烧热的测量技术,还... 采用线上+线下混合式教学模式开展教学改革,将热带作物材料和产品,包括椰肉、椰子油和油棕果实引入物理化学经典实验项目——燃烧热的测定。通过本实验,学生不仅掌握了块状固体、粉末状固体、液体三种不同外貌样品燃烧热的测量技术,还了解了“健康中国”“乡村振兴”“可持续发展”等国家战略的内涵和重大意义,丰富了课程内容,提高了学生学习的积极性,增强了教学过程中立德树人的协同效应,取得了良好的教学效果,具有很好的示范推广价值。 展开更多
关键词 物理化学实验 燃烧热的测定 课程思政 教学设计 热带作物
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高等教育中如何应用ChatGPT类生成式人工智能——联合国教科文组织《高等教育中的ChatGPT和人工智能:快速入门指南》解析
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作者 刘勇 徐佳慧 +1 位作者 董跃武 苏福根 《中国教育信息化》 2024年第2期71-80,共10页
ChatGPT引发的浪潮在为高等教育带来变革与创新的同时,也使高等教育面临着新问题与新挑战。为此,联合国教科文组织于2023年4月发布《高等教育中的ChatGPT和人工智能:快速入门指南》,用以阐释ChatGPT如何应用于高等教育。通过对该指南的... ChatGPT引发的浪潮在为高等教育带来变革与创新的同时,也使高等教育面临着新问题与新挑战。为此,联合国教科文组织于2023年4月发布《高等教育中的ChatGPT和人工智能:快速入门指南》,用以阐释ChatGPT如何应用于高等教育。通过对该指南的深入解读,详细分析了ChatGPT在高等教育中的教学、科研、管理、社区参与等方面的应用变革,并从学术诚信、监管问题、隐私问题、认知偏差、性别与多样化、可访问性、商业化等七个方面探讨了ChatGPT给高等教育带来的挑战和伦理问题。最后,提出高等教育机构如何使用ChatGPT的可行性建议:谨慎而有创造性地使用ChatGPT、构建理解和管理ChatGPT的能力、进行人工智能审核等,旨在为我国高等教育机构应用ChatGPT可能面临的机遇和挑战提供经验和启示,并为推动ChatGPT向可持续、公正和合乎伦理的方向发展提供借鉴与参考。 展开更多
关键词 人工智能 高等教育 生成式人工智能 伦理风险 聊天机器人
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Design,preparation,application of advanced array structured materials and their action mechanism analyses for high performance lithium-sulfur batteries
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作者 Nanping Deng Xiaofan Feng +7 位作者 yongbing Jin Zhaozhao Peng Yang Feng Ying Tian yong liu Lu Gao Weimin Kang Bowen Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期266-303,I0007,共39页
Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely comme... Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely commercial application and development of LSB is mainly hindered by serious“shuttle effect”of lithium polysulfides(Li PSs),slow reaction kinetics,notorious lithium dendrites,etc.In various structures of LSB materials,array structured materials,possessing the composition of ordered micro units with the same or similar characteristics of each unit,present excellent application potential for various secondary cells due to some merits such as immobilization of active substances,high specific surface area,appropriate pore sizes,easy modification of functional material surface,accommodated huge volume change,enough facilitated transportation for electrons/lithium ions,and special functional groups strongly adsorbing Li PSs.Thus many novel array structured materials are applied to battery for tackling thorny problems mentioned above.In this review,recent progresses and developments on array structured materials applied in LSBs including preparation ways,collaborative structural designs based on array structures,and action mechanism analyses in improving electrochemical performance and safety are summarized.Meanwhile,we also have detailed discussion for array structured materials in LSBs and constructed the structure-function relationships between array structured materials and battery performances.Lastly,some directions and prospects about preparation ways,functional modifications,and practical applications of array structured materials in LSBs are generalized.We hope the review can attract more researchers'attention and bring more studying on array structured materials for other secondary batteries including LSB. 展开更多
关键词 Array structured materials Preparation methods and structural designs Action mechanism analyses Advanced Li-S batteries Excellent electrochemical performances and safety
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Ultrasound-guided paravertebral nerve block anesthesia for percutaneous endoscopic laser unroofing treatment of symptomatic simple renal cysts—An innovative ambulatory surgery mode
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作者 Jia Hu Yuan Zhang +2 位作者 yong liu Xiao Yu Shaogang Wang 《Asian Journal of Urology》 CSCD 2024年第1期65-71,共7页
Objective:This study was designed to evaluate the feasibility,efficacy,and safety of percutaneous ureteroscopy laser unroofing as an ambulatory surgery for symptomatic simple renal cysts under multilevel paravertebral... Objective:This study was designed to evaluate the feasibility,efficacy,and safety of percutaneous ureteroscopy laser unroofing as an ambulatory surgery for symptomatic simple renal cysts under multilevel paravertebral nerve block anesthesia.Methods:From December 2015 to September 2017,33 simple renal cyst patients who had surgical indications were enrolled.Under ultrasound guidance,the T10/T11,T11/T12,and T12/L1 paravertebral spaces were identified,and 7-10 mL 0.5%ropivacaine was injected at each segment.Then a puncture needle was placed inside the cyst cavity under ultrasonic monitoring.A guidewire was introduced followed by sequential dilation up to 28/30 Fr.The extra parenchymal portion of the cyst wall was dissociated and incised using a thulium laser,and a pathological examination was performed.Results:Sensory loss to pinprick from T8 to L1 and sensory loss to ice from T6 to L2 were observed in all patients.None of the patients complained of pain during surgery.No serious complications occurred perioperatively.After the surgery,all patients recovered their lower limb muscle strength quickly,got out of bed,resumed oral feeding,and left the hospital within 24 h of admission.The pathologic diagnosis of all cyst walls was a simple renal cyst.The mean follow-up was 35.8 months.At the end of follow-up,the cyst units were reduced in size by more than 50%compared to the preoperative size,and no patient experienced a recurrence.Conclusion:Multi-level paravertebral nerve block for percutaneous ureteroscopy laser unroofing as an ambulatory surgery mode is feasible,safe,and effective for the treatment of simple renal cysts in selected patients. 展开更多
关键词 Paravertebralnerve blockanesthesia Percutaneous puncture Simplerenalcyst UNROOFING Ambulatorysurgery
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静电纺树枝状聚偏氟乙烯纳米纤维膜的制备
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作者 厉宗洁 王鑫慧 +5 位作者 王浩 贾梦格 王树业 赵良 刘雍 康卫民 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第6期71-77,共7页
通过向聚偏氟乙烯(PVDF)纺丝液中添加有机支化盐四丁基六氟磷酸铵(TBAHP),采用一步静电纺丝法制备了PVDF树枝状纳米纤维膜。探讨了TBAHP添加量、静电纺丝工艺参数及溶剂体积比对纤维树枝状形貌的影响,同时研究了TBAHP添加量对纤维膜力... 通过向聚偏氟乙烯(PVDF)纺丝液中添加有机支化盐四丁基六氟磷酸铵(TBAHP),采用一步静电纺丝法制备了PVDF树枝状纳米纤维膜。探讨了TBAHP添加量、静电纺丝工艺参数及溶剂体积比对纤维树枝状形貌的影响,同时研究了TBAHP添加量对纤维膜力学性能、孔径和孔隙率的影响。结果表明,TBAHP摩尔浓度为0.05 mol/L、N,N-二甲基甲酰胺(DMF)与丙酮(ACE)体积比为7:3、电压为27 kV、接收距离为12 cm时,制备的纳米纤维膜分支纤维较多,呈现形貌良好的树枝状结构,其断裂强度达4.93 MPa,远大于纯PVDF纳米纤维膜的1.82 MPa,孔径仅0.2μm,孔隙率达90%,在过滤、油水分离、电化学及膜蒸馏等领域具有很好的应用前景。 展开更多
关键词 静电纺丝 四丁基六氟磷酸铵 聚偏氟乙烯 树枝状纳米纤维
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Recent Advances in Understanding Multi-scale Climate Variability of the Asian Monsoon 被引量:1
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作者 Wen CHEN Renhe ZHANG +12 位作者 Renguang WU Zhiping WEN Liantong ZHOU Lin WANG Peng HU Tianjiao MA Jinling PIAO Lei SONG Zhibiao WANG Juncong LI Hainan GONG Jingliang HUANGFU yong liu 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第8期1429-1456,共28页
Studies of the multi-scale climate variability of the Asian monsoon are essential to an advanced understanding of the physical processes of the global climate system.In this paper,the progress achieved in this field i... Studies of the multi-scale climate variability of the Asian monsoon are essential to an advanced understanding of the physical processes of the global climate system.In this paper,the progress achieved in this field is systematically reviewed,with a focus on the past several years.The achievements are summarized into the following topics:(1)the onset of the South China Sea summer monsoon;(2)the East Asian summer monsoon;(3)the East Asian winter monsoon;and(4)the Indian summer monsoon.Specifically,new results are highlighted,including the advanced or delayed local monsoon onset tending to be synchronized over the Arabian Sea,Bay of Bengal,Indochina Peninsula,and South China Sea;the basic features of the record-breaking mei-yu in 2020,which have been extensively investigated with an emphasis on the role of multi-scale processes;the recovery of the East Asian winter monsoon intensity after the early 2000s in the presence of continuing greenhouse gas emissions,which is believed to have been dominated by internal climate variability(mostly the Arctic Oscillation);and the accelerated warming over South Asia,which exceeded the tropical Indian Ocean warming,is considered to be the main driver of the Indian summer monsoon rainfall recovery since 1999.A brief summary is provided in the final section along with some further discussion on future research directions regarding our understanding of the Asian monsoon variability. 展开更多
关键词 Asian monsoon multi-scale climate variability monsoon onset East Asian summer monsoon East Asian winter monsoon Indian summer monsoon
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原位构筑动态Cu/Ce(OH)_(x)界面用于高活性、高选择性和高稳定性硝酸盐还原合成氨
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作者 刘勇 赵晓丽 +5 位作者 隆昶 王晓艳 邓邦为 李康璐 孙艳娟 董帆 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第9期196-206,共11页
电催化硝酸根还原反应(NO_(3)^(-)RR)使用电子作为绿色还原剂,为去除和利用水中硝酸盐提供了一种有前景的技术.其中,铜基材料在碱性溶液(如1 mol L^(-1)KOH)中显示出较高的NO_(3)^(-)RR催化活性,但在中性条件下催化剂的性能不高.目前,... 电催化硝酸根还原反应(NO_(3)^(-)RR)使用电子作为绿色还原剂,为去除和利用水中硝酸盐提供了一种有前景的技术.其中,铜基材料在碱性溶液(如1 mol L^(-1)KOH)中显示出较高的NO_(3)^(-)RR催化活性,但在中性条件下催化剂的性能不高.目前,在中性体系中同时实现高活性、高选择性和高法拉第效率的氨合成是一个巨大的挑战.以往研究主要通过掺杂、合金化、调节晶面和引入缺陷等办法来提高NO_(3)^(-)RR的性能.此外,构筑异质结构界面可以调节催化剂的几何结构、电荷分布和配位环境,也是优化催化性能的一种有效策略.通过异质结构界面效应可以提供更多的催化活性位点,打破单组分催化剂的活性线性关系,进而提升NO_(3)^(-)RR性能.已有的研究中多采用直接化学合成法构筑铜基异质结催化剂,但在NO_(3)^(-)RR条件下原位制备异质结催化剂的文献报道较少,且已有的少数在NO_(3)^(-)RR条件下原位制备铜基异质结构的报道,由于界面性质不利、活性位点密度低,其催化NO_(3)^(-)RR的性能难以令人满意.因此,有必要采取有效的策略来原位构筑具有可调界面结构和丰富活性位点的铜基异质结构.本文提出了一种原位动态重构策略,通过构筑具有丰富界面活性位点的Cu/Ce(OH)_(x)催化剂以提高NO_(3)^(-)RR性能.在KCl溶液中将Ce(OH)_(x)电沉积到泡沫铜上,生成Cu_2Cl(OH)_(3)并与Ce(OH)_(x)一起沉积形成Cu_2Cl(OH)_(3)/Ce(OH)_(x)异质结构.在NO_(3)^(-)RR过程中,Cu_2Cl(OH)_3/Ce(OH)_(x)经历动态重构,原位形成了Cu/Ce(OH)_(x)催化剂.原位活化后,NO_(3)^(-)R性能显著增强,随后达到稳定状态.催化剂展现出较好的催化性能,NO_(3)^(-)转化率为100.0%,NH_(3)选择性为97.8%,NH_(3)法拉第效率为99.2%,并表现出长期稳定性,是中性介质中较先进的催化剂之一.采用X射线衍射(XRD)、扫描电镜(SEM)、高分辨透射电镜(HRTEM)、选区电子衍射(SAED)、X射线光电子能谱(XPS)及原位拉曼光谱表征了Cu_(2)Cl(OH)_(3)/Ce(OH)_(x)预催化剂的原位重构过程.XRD结果表明,Cu_(2)Cl(OH)_(3)/Ce(OH)_(x)预催化剂在第一次NO_(3)^(-)RR测试后还原形成了Cu/Ce(OH)_(x).SEM结果表明,Cu_(2)Cl(OH)_(3)颗粒在第一次NO_(3)^(-)RR循环后开始形成裂纹,第二次NO_(3)^(-)RR后碎裂成几十至100 nm的颗粒,其上存在大量Ce(OH)_(x)纳米粒子.HRTEM和SAED结果证实了上述结构变化.XPS结果表明,铜在原位重构过程中逐渐从高价态还原到低价态.原位拉曼光谱进一步确认Cu_(2)Cl(OH)_(3)还原为Cu_(2)O再到Cu的动态转变过程.原位和非原位表征结果一致表明,Cu_(2)Cl(OH)_(3)/Ce(OH)_(x)异质结构经历了动态还原和纳米化过程,原位构筑了具有丰富活性位点的Cu/Ce(OH)_(x)界面.采用在线微分电化学质谱(DEMS)和密度泛函理论(DFT)研究了NO_(3)^(-)RR性能增强机理.DEMS结果表明,Cu/Ce(OH)_(x)上存在NO,HNO/NOH和NH_(2)OH中间体.DFT结果表明,Cu/Ce(OH)_(x)界面位点具有以下作用:(1)促进硝酸根的吸附和活化;(2)降低了电位限制步骤(NO*→HNO*)的反应能垒;(3)通过增强氢吸附强度,抑制了析氢副反应的发生.此外,原位纳米化形成的丰富界面活性位点也促进了NO_(3)^(-)RR活性的提升.综上,本文提出了一种原位构筑动态界面活性位点的策略,从而增强电催化性能,以实现高价值化学品的可持续合成.未来可改变前驱体种类将该方法拓展至其他催化剂体系,探索其在多种电催化反应中的应用. 展开更多
关键词 金属/氢氧化物界面 原位构筑 电催化硝酸根还原 氨合成 选择性
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Regeneration of spent LiFePO4 as a high-performance cathode material by a simultaneous coating and doping strategy 被引量:1
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作者 Hui Tong Yi Li +4 位作者 Gaoqiang Mao Chaolei Wang Wanjing Yu yong liu Mudan liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第6期1162-1170,共9页
With the number of decommissioned electric vehicles increasing annually,a large amount of discarded power battery cathode material is in urgent need of treatment.However,common leaching methods for recovering metal sa... With the number of decommissioned electric vehicles increasing annually,a large amount of discarded power battery cathode material is in urgent need of treatment.However,common leaching methods for recovering metal salts are economically inefficient and polluting.Meanwhile,the recycled material obtained by lithium remediation alone has limited performance in cycling stability.Herein,a short method of solid-phase reduction is developed to recover spent LiFePO4 by simultaneously introducing Mg2+ions for hetero-atom doping.Issues of particle agglomeration,carbon layer breakage,lithium loss,and Fe3+defects in spent LiFePO4 are also addressed.Results show that Mg2+addition during regeneration can remarkably enhance the crystal structure stability and improve the Li+diffusion coefficient.The regenerated LiFePO4 exhibits significantly improved electrochemical performance with a specific discharge capacity of 143.2 mAh·g^(−1)at 0.2 C,and its capacity retention is extremely increased from 37.9%to 98.5%over 200 cycles at 1 C.Especially,its discharge capacity can reach 95.5 mAh·g^(−1)at 10 C,which is higher than that of spent LiFePO4(55.9 mAh·g^(−1)).All these results show that the proposed regeneration strategy of simultaneous carbon coating and Mg2+doping is suitable for the efficient treatment of spent LiFePO4. 展开更多
关键词 spent LiFePO4 solid-phase reduction repair and regeneration cathode materials lithium-ion batteries
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Metallurgical properties of CaO–SiO_(2)–Al_(2)O_(3)–4.6wt%MgO–Fe_(2)O_(3)slag system pertaining to spent automotive catalyst smelting
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作者 Ruili Zheng Jianfang Lü +5 位作者 Weifeng Song Mudan liu Huashan Li yong liu Xianjin Lü Zhiyuan Ma 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第5期886-896,共11页
The metallurgical properties of the CaO–SiO_(2)–Al_(2)O_(3)–4.6wt%Mg O–Fe_(2)O_(3)slag system,formed by the co-treatment process of spent automotive catalyst(SAC)and copper-bearing electroplating sludge(CBES),were... The metallurgical properties of the CaO–SiO_(2)–Al_(2)O_(3)–4.6wt%Mg O–Fe_(2)O_(3)slag system,formed by the co-treatment process of spent automotive catalyst(SAC)and copper-bearing electroplating sludge(CBES),were studied systematically in this paper.The slag structure,melting temperature,and viscous characteristics were investigated by Fourier transform infrared(FTIR)spectroscopy,Raman spectroscopy,Fact Sage calculation,and viscosity measurements.Experimental results show that the increase of Fe_(2)O_(3)content(3.8wt%–16.6wt%),the mass ratio of CaO/SiO_(2)(m(CaO)/m(SiO_(2)),0.5–1.3),and the mass ratio of SiO_(2)/Al_(2)O_(3)(m(SiO_(2))/m(Al_(2)O_(3)),1.0–5.0)can promote the depolymerization of silicate network,and the presence of a large amount of Fe_(2)O_(3)in form of tetrahedral and octahedral units ensures the charge compensation of Al^(3+)ions and makes Al_(2)O_(3)only behave as an acid oxide.Thermodynamic calculation and viscosity measurements show that with the increase of Fe_(2)O_(3)content,m(Ca O)/m(SiO_(2)),and m(SiO_(2))/m(Al_(2)O_(3)),the depolymerization of silicate network structure and low-melting-point phase transformation first occur within the slag,leading to the decrease in melting point and viscosity of the slag,while further increase causes the formation of high-melting-point phase and a resultant re-increase in viscosity and melting point.Based on experimental analysis,the preferred slag composition with low polymerization degree,viscosity,and melting point is as follows:Fe_(2)O_(3)content of 10.2wt%–13.4wt%,m(CaO)/m(SiO_(2))of 0.7–0.9 and m(SiO_(2))/m(Al_(2)O_(3))of 3.0–4.0.This work provides a theoretical support for slag design in co-smelting process of SAC and CBES. 展开更多
关键词 spent automotive catalyst co-treatment slag system slag structure melting temperature phase transformation VISCOSITY
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Axial length,vitreoretinal pathology,and anterior chamber depth can predict postoperative refractive outcomes in phacovitrectomy/silicone oil removal
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作者 Xu Chen He Zhao +6 位作者 Jia-Yun Ren Lu Wang Jun-Li Wan Bo liu Nan Wu Xi liu yong liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第4期554-562,共9页
AIM:To evaluate the postoperative refractive prediction error(PE)and determine the factors that af fect the refractive outcomes of combined pars plana vitrectomy(PPV)or silicone oil removal(SOR)with cataract surgery.M... AIM:To evaluate the postoperative refractive prediction error(PE)and determine the factors that af fect the refractive outcomes of combined pars plana vitrectomy(PPV)or silicone oil removal(SOR)with cataract surgery.METHODS:The study is a retrospective,case-series study.Totally 301 eyes of 301 patients undergoing combined PPV/SOR with cataract surgery were enrolled.Eligible individuals were separated into four groups according to their preoperative diagnoses:silicone oil-filled eyes after PPV(group 1),epiretinal membrane(group 2),macular hole(group 3),and primary retinal detachment(RD;group 4).The variables af fecting postoperative refractive outcomes were analyzed,including age,gender,preoperative best-corrected visual acuity(BCVA),axial length(AL),keratometry average,anterior chamber depth(ACD),intraocular tamponade,and vitreoretinal pathology.The outcome measurements include the mean refractive PE and the proportions of eyes with a PE within±0.50 diopter(D)and±1.00 D.RESULTS:For all patients,the mean PE was-0.04±1.17 D,and 50.17%of patients(eyes)had a PE within±0.50 D.There was a significant difference in refractive outcomes among the four groups(P=0.028),with RD(group 4)showing the least favorable refractive outcome.In multivariate regression analysis,only AL,vitreoretinal pathology,and ACD were strongly associated with PE(all P<0.01).Univariate analysis revealed that longer eyes(AL>26 mm)and a deeper ACD were correlated with hyperopic PE,and shorter eyes(AL<26 mm)and a shallower ACD were correlated with myopic PE.CONCLUSION:RD patients have the least favorable refractive outcome.AL,vitreoretinal pathology,and ACD are strongly associated with PE in the combined surgery.These three factors affect refractive outcomes and thus can be used to predict a better postoperative refractive outcome in clinical practice. 展开更多
关键词 axial length vitreoretinal pathology anterior chamber depth intraocular lens pars plana vitrectomy silicone oil removal CATARACT combined surgery refractive error intraocular tamponade
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Mechanical and hydraulic properties of fault rocks under multi‑stage cyclic loading and unloading
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作者 Wentao Hou Dan Ma +3 位作者 Qiang Li Jixiong Zhang yong liu Chenyao Zhou 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第4期151-170,共20页
The rock mass in fault zones is frequently subjected to cyclic loading and unloading during deep resource exploitation and tunnel excavation.Research on the mechanical and hydraulic characteristics of fault rock durin... The rock mass in fault zones is frequently subjected to cyclic loading and unloading during deep resource exploitation and tunnel excavation.Research on the mechanical and hydraulic characteristics of fault rock during the cyclic loading and unloading is of great signifcance for revealing the formation mechanism of water-conducting pathways in fault and preventing water inrush disasters.In this study,the mechanical and seepage tests of fault rock under the multi-stage cyclic loading and unloading of axial compression were carried out by using the fuid–solid coupling triaxial experimental device.The hysteresis loop of the stress–strain curve,peak strain rate,secant Young's modulus,and permeability of fault rock were obtained,and the evolution law of the dissipated energy of fault rock with the cyclic number of load and unloading was discussed.The experimental results show that with an increase in the cyclic number of loading and unloading,several changes occur.The hysteresis loop of the stress–strain curve of the fault rock shifts towards higher levels of strain.Additionally,both the peak strain rate and the secant Young's modulus of the fault rock increase,resulting in an increase in the secant Young's modulus of the fault rock mass.However,the growth rate of the secant Young's modulus gradually slows down with the increase of cyclic number of loading and unloading.The permeability evolution of fault rock under the multi-stage cyclic loading and unloading of axial compression can be divided into three stages:steady increase stage,cyclic decrease stage,and rapid increase stage.Besides,the calculation model of dissipated energy of fault rock considering the efective stress was established.The calculation results show that the relationship between the dissipated energy of fault rock and the cyclic number of loading and unloading conforms to an exponential function. 展开更多
关键词 Multi-stage cyclic loading and unloading Fault rocks Mechanical properties Hydraulic properties Energy dissipation
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Association Between Constipation and a Reduction in Lower Limb Muscle Strength in Preoperative Patients with Thoracic Spinal Tumors
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作者 yong liu Si-Yuan Yao +2 位作者 Xi Zhou Shu-Zhong liu Yan-Yan Bian 《Chinese Medical Sciences Journal》 CAS CSCD 2023年第2期109-116,共8页
Objective To investigate the clinical symptoms experienced by patients with thoracic spinal tumors and verify the associated symptoms that are predictive of a decline in muscle strength in the lower limbs.Methods A si... Objective To investigate the clinical symptoms experienced by patients with thoracic spinal tumors and verify the associated symptoms that are predictive of a decline in muscle strength in the lower limbs.Methods A single-center,retrospective cross-sectional study was conducted on in-patients diagnosed with epidural thoracic spinal tumors between January 2011 and May 2021.The study involved a review of electronic medical records and radiographs and the collection of clinical data.The differences in clinical manifestations between patients with constipation and those without constipation were analyzed.Binary logistic regression analyses were performed to identify risk factors associated with a decline in muscle strength in the lower limbs.Results A total of 227 patients were enrolled,including 131 patients with constipation and 96 without constipation.The constipation group had a significantly higher proportion of patients who experienced difficulty walking or paralysis compared to those without constipation prior to surgery(83.2%vs.17.7%,χ~2=99.035,P 0.001).Constipation(OR=9.522,95%CI:4.150±21.849,P 0.001)and urinary retention(OR=14.490,95%CI:4.543±46.213,P 0.001)were independent risk factors for muscle strength decline in the lower limbs.Conclusions The study observed that patients with thoracic spinal tumors who experienced constipation symptoms had a higher incidence of lower limb weakness.Moreover,the analysis revealed that constipation and urinary retention were independent risk factors associated with a preoperative decline in muscle strength of lower limbs. 展开更多
关键词 CONSTIPATION thoracic spinal tumors muscle strength decline preoperation surgical intervention
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Perioperative immunotherapy for esophageal squamous cell carcinoma:Now and future
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作者 yong liu 《World Journal of Gastroenterology》 SCIE CAS 2023年第34期5020-5037,共18页
Esophageal cancer(EC)ranks among the most prevalent malignant tumors affecting the digestive tract.Esophageal squamous cell carcinoma(ESCC)stands as the prevailing pathological subtype,encompassing approximately 90%of... Esophageal cancer(EC)ranks among the most prevalent malignant tumors affecting the digestive tract.Esophageal squamous cell carcinoma(ESCC)stands as the prevailing pathological subtype,encompassing approximately 90%of all EC patients.In clinical stage II-IVA locally advanced ESCC cases,the primary approach to treatment involves a combination of neoadjuvant therapy and surgical resection.Despite concerted efforts,the long-term outcomes for ESCC patients remain unsatisfactory,with dismal prognoses.However,recent years have witnessed remarkable strides in immunotherapy,particularly in the secondand first-line treatment of advanced or metastatic ESCC,with the development of monoclonal antibodies that inhibit programmed death 1 or programmed death ligand 1 demonstrating encouraging responses and perioperative clinical benefits for various malignancies,including ESCC.This comprehensive review aims to present the current landscape of perioperative immunotherapy for resectable ESCC,focusing specifically on the role of immune checkpoint inhibitors during the perioperative period.Additionally,the review will explore promising biomarkers and offer insights into future prospects. 展开更多
关键词 Esophageal squamous cell carcinoma Immune checkpoint inhibitors IMMUNOTHERAPY NEOADJUVANT Randomized clinical trial
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Interdecadal Enhancement in the Relationship between the Western North Pacific Summer Monsoon and Sea Surface Temperature in the Tropical Central-Western Pacific after the Early 1990s
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作者 Kui liu Lian-Tong ZHOU +1 位作者 Zhibiao WANG yong liu 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第10期1766-1782,共17页
This study reveals the strengthened interdecadal relationship between the western North Pacific summer monsoon(WNPSM)and tropical central-western Pacific sea surface temperature anomaly(SSTA)in summer after the early ... This study reveals the strengthened interdecadal relationship between the western North Pacific summer monsoon(WNPSM)and tropical central-western Pacific sea surface temperature anomaly(SSTA)in summer after the early 1990s.In the first period(1979–91,P1),the WNPSM-related precipitation anomaly and horizontal wind anomaly present themselves as an analogous Pacific-Japan(PJ)-like pattern,generally considered to be related to the Niño-3 index in the preceding winter.During the subsequent period(1994–2019,P2),the WNPSM-related precipitation anomaly presents a zonal dipole pattern,correlated significantly with the concurrent SSTA in the Niño-4 and tropical western Pacific regions.The negative(positive)SSTA in the tropical western Pacific and positive(negative)SSTA in the Niño-4 region,could work together to influence the WNPSM,noting that the two types of anomalous SSTA configurations enhance(weaken)the WNPSM by the positive(negative)phase PJ-like wave and Gill response,respectively,with an anomalous cyclone(anticyclone)located in the WNPSM,which shows obvious symmetry about the anomalous circulation.Specifically,the SSTA in Niño-4 impacts the WNPSM by an atmospheric Gill response,with a stronger(weaker)WNPSM along with a positive(negative)SSTA in the Niño-4 region.Furthermore,the SSTA in the tropical western Pacific exerts an influence on the WNPSM by a PJ-like wave,with a stronger(weaker)WNPSM along with a negative(positive)SSTA in the tropical western Pacific.In general,SSTAs in the tropical western Pacific and Niño-4 areas could work together to exert influence on the WNPSM,with the effect most likely to occur in the El Niño(La Niña)developing year in P2.However,the SSTAs in the tropical western Pacific worked alone to exert an influence on the WNPSM mainly in 2013,2014,2016,and 2017,and the SSTAs in the Niño-4 region worked alone to exert an influence on the WNPSM mainly in Central Pacific(CP)La Niña developing years.The sensitivity experiments also can reproduce the PJ-like wave/Gill response associated with SSTA in the tropical western Pacific/Niño-4 regions.Therefore,the respective and synergistic impacts from the Niño-4 region and the tropical western Pacific on the WNPSM have been revealed,which helps us to acquire a better understanding of the interdecadal variations of the WNPSM and its associated climate influences. 展开更多
关键词 western North Pacific summer monsoon tropical central-western Pacific SST interdecadal change
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Statistical learning prediction of fatigue crack growth via path slicing and re-weighting
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作者 Yingjie Zhao yong liu Zhiping Xu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第6期415-423,共9页
Predicting potential risks associated with the fatigue of key structural components is crucial in engineering design.However,fatigue often involves entangled complexities of material microstructures and service condit... Predicting potential risks associated with the fatigue of key structural components is crucial in engineering design.However,fatigue often involves entangled complexities of material microstructures and service conditions,making diagnosis and prognosis of fatigue damage challenging.We report a statistical learning framework to predict the growth of fatigue cracks and the life-to-failure of the components under loading conditions with uncertainties.Digital libraries of fatigue crack patterns and the remaining life are constructed by high-fidelity physical simulations.Dimensionality reduction and neural network architectures are then used to learn the history dependence and nonlinearity of fatigue crack growth.Path-slicing and re-weighting techniques are introduced to handle the statistical noises and rare events.The predicted fatigue crack patterns are self-updated and self-corrected by the evolving crack patterns.The end-to-end approach is validated by representative examples with fatigue cracks in plates,which showcase the digital-twin scenario in real-time structural health monitoring and fatigue life prediction for maintenance management decision-making. 展开更多
关键词 Fatigue crack growth Structural health monitoring Statistical noises Rare events Digital libraries
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Surface structure modification of ReSe2 nanosheets via carbon ion irradiation
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作者 乔梅 王铁军 +3 位作者 刘泳 刘涛 刘珊 许士才 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期385-390,共6页
The effects of C ion irradiation on multilayer ReSe2flakes are studied by utilizing different kinds of technologies. The domain sizes, thickness, morphologies of the multilayer ReSe2flakes on the Al2O3substrates befor... The effects of C ion irradiation on multilayer ReSe2flakes are studied by utilizing different kinds of technologies. The domain sizes, thickness, morphologies of the multilayer ReSe2flakes on the Al2O3substrates before and after 1.0-MeV C ion irradiation with different fluence rates are studied by atomic force microscope and scanning electron microscopy. The atomic vibrational spectra of multilayer ReSe2flakes are detected by micro-Raman spectra. The redshifts of the Raman modes after 1.0-MeV C ion irradiation are observed from the micro-Raman spectra. The elemental compositions and bonding configurations of the multilayer ReSe2samples before and after irradiation processes are characterized by x-ray photoelectron spectroscopy. The structural properties are also investigated by x-ray diffraction, and it is concluded that after 1.0-MeV C ion irradiation process, multilayer ReSe2samples continue to grow on Al2O3substrates, the increase of crystallite size also reveals that the crystallinity is improved with the increase of the layer number after 1.0-MeV C ion irradiation. 展开更多
关键词 ion irradiation MICROSTRUCTURE CRYSTALLINITY surface morphology
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Design optimization of high breakdown voltage vertical GaN junction barrier Schottky diode with high-K/low-K compound dielectric structure
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作者 田魁元 刘勇 +1 位作者 杜江锋 于奇 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期470-477,共8页
A vertical junction barrier Schottky diode with a high-K/low-K compound dielectric structure is proposed and optimized to achieve a high breakdown voltage(BV).There is a discontinuity of the electric field at the inte... A vertical junction barrier Schottky diode with a high-K/low-K compound dielectric structure is proposed and optimized to achieve a high breakdown voltage(BV).There is a discontinuity of the electric field at the interface of high-K and low-K layers due to the different dielectric constants of high-K and low-K dielectric layers.A new electric field peak is introduced in the n-type drift region of junction barrier Schottky diode(JBS),so the distribution of electric field in JBS becomes more uniform.At the same time,the effect of electric-power line concentration at the p-n junction interface is suppressed due to the effects of the high-K dielectric layer and an enhancement of breakdown voltage can be achieved.Numerical simulations demonstrate that GaN JBS with a specific on-resistance(R_(on,sp)) of 2.07 mΩ·cm^(2) and a BV of 4171 V which is 167% higher than the breakdown voltage of the common structure,resulting in a high figure-of-merit(FOM) of 8.6 GW/cm^(2),and a low turn-on voltage of 0.6 V. 展开更多
关键词 GaN junction barrier Schottky diode compound dielectric breakdown voltage turn-on voltage
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Outcomes and risk factors for failure of trabeculectomy in glaucomatous patients in Southwest China:a 325 eyes analysis
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作者 Zuo-Xin Qin Xi Ying +6 位作者 Qing Han Lu Wang Lian Tan Yu-Fei Xu Qiu-Xiang You Nan Wu yong liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第3期367-374,共8页
AIM:To evaluate the outcomes and elucidate the failure factors for trabeculectomy with mitomycin C(MMC)in Southwest Chinese patients.METHODS:A retrospective correlational study was conducted on the glaucomatous patien... AIM:To evaluate the outcomes and elucidate the failure factors for trabeculectomy with mitomycin C(MMC)in Southwest Chinese patients.METHODS:A retrospective correlational study was conducted on the glaucomatous patients who underwent initial trabeculectomy with MMC in Southwest Hospital and had been followed up for 1-3y.A complete success for surgery is defined as a postoperative intraocular pressure(IOP)>5 and≤21 mm Hg and 20%reduction of IOP compared to preoperative,without IOP-lowering medications.A qualified success for surgery is defined as the abovementioned postoperative IOP with or without IOP-lowering medications.The primary outcomes were IOP,the number of IOP-lowering medications,and cumulative success rate.The secondary outcomes included best corrected visual acuity(BCVA),mean deviation(MD)of visual field,major complications,and risk factors for surgical failure.RESULTS:A total of 325 eyes of 261 glaucomatous patients had been included in our study.Both the mean IOP and the number of IOP-lowering medications were significantly decreased from 32.9±12.0 to 16.4±5.7 mm Hg(P<0.0001)and 3.0±0.9 to 0.9±1.0(P<0.0001),respectively,at the last visit.The cumulative complete success rate and qualified success rate were 77.8%and 92.0%at 1-year follow-up,and 47.2%and 77.7%at 3-year follow up.There were no significant differences in surgical outcomes between primary angle-closure glaucoma(PACG)and primary open angle glaucoma(POAG).In PACG patients,the success rates of trabeculectomy were comparable with those of phacotrabeculectomy.Hypertension(HR=1.904,P=0.011),encapsulated bleb(HR=2.756,P<0.001),and more preoperative topical medications(HR=2.475,P=0.008)were risk factors for surgical failure.CONCLUSION:The qualified success rate of trabeculectomy with MMC in glaucomatous patients in the cohort is 92.0%at 1-year,and 77.7%at 3-year follow up.Hypertension,encapsulated bleb,and more preoperative topical medications are associated with surgical failure. 展开更多
关键词 GLAUCOMA TRABECULECTOMY OUTCOMES risk factors
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RNA-binding protein CPSF6 regulates IBSP to affect pyroptosis in gastric cancer
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作者 Xue-Jun Wang yong liu +2 位作者 Bin Ke Li Zhang Han Liang 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第9期1531-1543,共13页
BACKGROUND Extensive evidence has illustrated the promotive role of integrin binding sialoprotein(IBSP)in the progression of multiple cancers.However,little is known about the functions of IBSP in gastric cancer(GC)pr... BACKGROUND Extensive evidence has illustrated the promotive role of integrin binding sialoprotein(IBSP)in the progression of multiple cancers.However,little is known about the functions of IBSP in gastric cancer(GC)progression.AIM To investigate the mechanism underlying the regulatory effects of IBSP in GC progression,and the relationship between IBSP and cleavage and polyadenylation factor 6(CPSF6)in this process.METHODS The mRNA and protein expression of relevant genes were assessed through realtime quantitative polymerase chain reaction and Western blot,respectively.Cell viability was evaluated by Cell Counting Kit-8 assay.Cell invasion and migration were evaluated by Transwell assay.Pyroptosis was measured by flow cytometry.The binding between CPSF6 and IBSP was confirmed by luciferase reporter and RNA immunoprecipitation(RIP)assays.RESULTS IBSP exhibited higher expression in GC tissues and cell lines than in normal tissues and cell lines.IBSP knockdown suppressed cell proliferation,migration,and invasion but facilitated pyroptosis.In the exploration of the regulatory mechanism of IBSP,potential RNA binding proteins for IBSP were screened with catRAPID omics v2.0.The RNA-binding protein CPSF6 was selected due to its higher expression in stomach adenocarcinoma.Luciferase reporter and RIP assays revealed that CPSF6 binds to the 3’-untranslated region of IBSP and regulates its expression.Knockdown of CPSF6 inhibited cell proliferation,migration,and invasion but boosted pyroptosis.Through rescue assays,it was uncovered that the retarded GC progression mediated by CPSF6 knockdown was reversed by IBSP overexpression.CONCLUSION Our study highlighted the vital role of the CPSF6/IBSP axis in GC,suggesting that IBSP might be an effective biotarget for GC treatment. 展开更多
关键词 Integrin binding sialoprotein Cleavage and polyadenylation factor 6 PYROPTOSIS Gastric cancer
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Al和Mo对难熔高熵合金高温氧化行为的影响(英文) 被引量:22
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作者 曹远奎 刘咏 +3 位作者 刘彬 张卫东 王家文 杜萌 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第7期1476-1483,共8页
难熔高熵合金在高温下具有优异的力学性能,其高温氧化行为非常重要。本文作者研究TiNbTa0.5Zr、TiNbTa0.5ZrAl 及TiNbTa0.5ZrAlMo0.5 3 种合金的高温氧化行为,并讨论合金元素的影响。研究结果表明,TiNbTa0.5Zr 及TiNbTa0.5ZrAl 合金的... 难熔高熵合金在高温下具有优异的力学性能,其高温氧化行为非常重要。本文作者研究TiNbTa0.5Zr、TiNbTa0.5ZrAl 及TiNbTa0.5ZrAlMo0.5 3 种合金的高温氧化行为,并讨论合金元素的影响。研究结果表明,TiNbTa0.5Zr 及TiNbTa0.5ZrAl 合金的氧化速率受扩散控制,符合指数型氧化规律。但TiNbTa0.5ZrAlMo0.5 合金的氧化速率受界面反应控制,符合直线型氧化规律。添加Al 可形成氧化保护膜从而提高合金的抗氧化性能;然而,添加Mo 会破坏富Al 保护膜。TiNbTa0.5ZrAlMo0.5 合金的氧化膜中出现大量的孔洞和裂纹,导致其抗氧化性能明显下降。 展开更多
关键词 高熵合金 难熔金属 高温氧化 氧化膜 显微组织
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