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1例EGFR L747S和L858R双突变肺腺癌患者的治疗
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作者 王腾飞 欧阳雯 +2 位作者 张俊红 张弓 谢丛华 《数理医药学杂志》 CAS 2023年第3期230-235,共6页
表皮生长因子受体(epidermal growth factor receptor,EGFR)突变中最常见的突变是外显子19缺失突变和外显子21 L858R突变,这两种突变都对EGFR酪氨酸激酶抑制剂(EGFR-tyrosine kinase inhibitors,EGFR-TKIs)有非常好的响应性。然而,EGFR-... 表皮生长因子受体(epidermal growth factor receptor,EGFR)突变中最常见的突变是外显子19缺失突变和外显子21 L858R突变,这两种突变都对EGFR酪氨酸激酶抑制剂(EGFR-tyrosine kinase inhibitors,EGFR-TKIs)有非常好的响应性。然而,EGFR-TKIs对罕见EGFR突变的疗效尚有争议。在治疗过程中,许多患者最终也会对EGFR-TKIs产生耐药性。此外,对于对奥希替尼产生耐药性的患者,特别是那些具有罕见或复杂突变的患者,仍然没有标准的治疗方案。本文介绍了1例具有EGFR L747S和L858R双突变的肺腺癌患者,该患者在出现奥希替尼耐药后接受帕博利珠单抗联合化疗治疗有效,且无疾病进展生存期为13个月。这是国内外首例在携带EGFR L747S和L858R双突变的肺腺癌患者对奥希替尼耐药之后使用帕博利珠单抗免疫治疗联合化疗的报道,本案例可为具有类似罕见突变患者的治疗提供参考。 展开更多
关键词 EGFR L747S突变 肺腺癌 奥希替尼 帕博利珠单抗
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Pore structure evolution during the coke graphitization process in a blast furnace 被引量:4
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作者 Hao-bin Zhu Wen-long Zhan +3 位作者 Zhi-jun He Ying-chang Yu Qing-hai Pang jun-hong zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第9期1226-1233,共8页
Pore structure is an important factor influencing coke strength,while the property of coke is essential to maintaining gas and liquid permeability in a blast furnace.Therefore,an in-depth understanding of the pore str... Pore structure is an important factor influencing coke strength,while the property of coke is essential to maintaining gas and liquid permeability in a blast furnace.Therefore,an in-depth understanding of the pore structure evolution during the graphitization process can reveal the coke size degradation behavior during its descent in a blast furnace.Coke graphitization was simulated at different heating temperatures from 1100 to 1600℃ at intervals of 100℃.The quantitative evaluation of the coke pore structure with different graphitization degree was determined by vacuum drainage method and nitrogen adsorption method.Results show that the adsorption and desorption curves of graphitized coke have intersection points,and the two curves did not coincide,instead forming a“hysteresis loop.”Based on the hysteresis loop analysis,the porous structure of the graphitized coke mostly appeared in the shape of a“hair follicle.”Furthermore,with an increase in heating temperature,the apparent porosity,specific surface area,total pore volume,and amount of micropores showed good correlation and can divided into three stages:1100-1200,1200-1400,and 1400-1600℃.When the temperature was less than 1400℃,ash migration from the inner part mainly led to changes in the coke pore structure.When the temperature was greater than 1400℃,the pore structure evolution was mainly affected by the coke graphitization degree.The results of scanning electron microscopy,energy dispersive spectrometry,and ash content analyses also confirmed that the migration of the internal ash to the surface of the matrix during the graphitization process up to 1400℃ contributed to these changes. 展开更多
关键词 COKE blast furnace GRAPHITIZATION pore structure ash migration
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Generation and evolution of multiple operation states in passively mode-locked thulium-doped fiber laser by using a graphene-covered-microfiber 被引量:3
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作者 王小发 张俊红 +1 位作者 彭晓玲 毛雪峰 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期301-307,共7页
Using graphene-covered-microfiber (GCM) as a saturable absorber, the generation and evolution of multiple operation states are proposed and demonstrated in passively mode-locked thulium-doped fiber laser. The microf... Using graphene-covered-microfiber (GCM) as a saturable absorber, the generation and evolution of multiple operation states are proposed and demonstrated in passively mode-locked thulium-doped fiber laser. The microfiber was fabricated using the flame brushing method to an interaction length of - 1.2 cm with a waist diameter of -10 μm. Graphene layers were grown on copper foils by chemical vapor deposition and transferred onto the polydimethylsiloxane (PDMS) to form a PDMS/graphene film, which allowed light-graphene interaction via evanescent field. With the increase of the pump power from 1.25 W to 2.15 W, five different lasing regimes, including continuous-wave, conventional soliton mode-locking, multi- soliton mode-locking, a period of transition, and noise-like mode-locking, were achieved in a fiber ring cavity. To the best of our knowledge, it is the first report of the generation and evolution of multiple operation states by covering graphene on the microfiber in the 2-μ.m region. The results demonstrate that GCM can be a promising method for fabricating all fiber SA, and the switchable operation states can provide more portability in complex application domain. 展开更多
关键词 fiber lasers mode-locked thulium-doped fiber graphene MICROFIBER
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Xiangbinfang granules enhance gastric antrum motility via intramuscular interstitial cells of Cajal in mice 被引量:2
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作者 Qi-Cheng Chen Zhi Jiang +2 位作者 jun-hong zhang Li-Xing Cao Zhi-Qiang Chen 《World Journal of Gastroenterology》 SCIE CAS 2021年第7期576-591,共16页
BACKGROUND Interdigestive migrating motor complexes(MMC)produce periodic contractions in the gastrointestinal tract,but the exact mechanism of action still remains unclear.Intramuscular interstitial cells of Cajal(ICC... BACKGROUND Interdigestive migrating motor complexes(MMC)produce periodic contractions in the gastrointestinal tract,but the exact mechanism of action still remains unclear.Intramuscular interstitial cells of Cajal(ICC-IM)participate in gastrointestinal hormone and neuromodulation,but the correlation between ICCIM and MMC is also unclear.We found that xiangbinfang granules(XBF)mediated the phase III contraction of MMC.Here,the effects of XBF on gastric antrum motility in W/Wv mice and the effects of ICC-IM on gastric antrum MMC are reported.AIM To observe the effects of ICC-IM on gastric antrum motility and to establish the mechanism of XBF in promoting gastric antrum motility.METHODS The density of c-kit-positive ICC myenteric plexus(ICC-MP)and ICC-IM in the antral muscularis of W/Wv and wild-type(WT)mice was examined by confocal microscopy.The effects of XBF on gastric antrum slow waves in W/Wv and WT mice were recorded by intracellular amplification recording.Micro-strain-gauge force transducers were implanted into the gastric antrum to monitor the MMC and the effect of XBF on gastric antrum motility in conscious W/Wv and WT mice.RESULTS In the gastric antrum of W/Wv mice,c-kit immunoreactivity was significantly reduced,and no ICC-IM network was observed.Spontaneous rhythmic slow waves also appeared in the antrum of W/Wv mice,but the amplitude of the antrum slow wave decreased significantly in W/Wv mice(22.62±2.23 mV vs 2.92±0.52 mV,P<0.0001).MMCs were found in 7 of the 8 WT mice but no complete MMC cycle was found in W/Wv mice.The contractile frequency and amplitude index of the gastric antrum were significantly increased in conscious WT compared to W/Wv mice(frequency,3.53±0.18 cpm vs 1.28±0.12 cpm;amplitude index,23014.26±1798.65 mV·20 min vs 3782.16±407.13 mV·20 min;P<0.0001).XBF depolarized smooth muscle cells of the gastric antrum in WT and W/Wv mice in a dose-dependent manner.Similarly,the gastric antrum motility in WT mice was significantly increased after treatment with XBF 5 mg(P<0.05).Atropine(0.1 mg/kg)blocked the enhancement of XBF in WT and W/Wv mice completely,while tetrodotoxin(0.05 mg/kg)partially inhibited the enhancement by XBF.CONCLUSION ICC-IM participates in the regulation of gastric antrum MMC in mice.XBF induces MMC III-like contractions that enhance gastric antrum motility via ICCIM in mice. 展开更多
关键词 Interstitial cells of Cajal Migrating motor complex W/Wv Gastric antrum motility Xiangbinfang granules Chinese medicine
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Impact of water and sediment discharges on subaqueous delta evolution in Yangtze Estuary from 1950 to 2010 被引量:2
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作者 Yun-ping YANG Yi-tian LI +1 位作者 Yong-yang FAN jun-hong zhang 《Water Science and Engineering》 EI CAS CSCD 2014年第3期331-343,共13页
In order to determine how the subaqueous delta evolution depends on the water and sediment processes in the Yangtze Estuary, the amounts of water and sediment discharged into the estuary were studied. The results show... In order to determine how the subaqueous delta evolution depends on the water and sediment processes in the Yangtze Estuary, the amounts of water and sediment discharged into the estuary were studied. The results show that, during the period from 1950 to 2010, there was no significant change in the annual water discharge, and the multi-annual mean water discharge increased in dry seasons and decreased in flood seasons. However, the annual sediment discharge and the multi-annual mean sediment discharge in flood and dry seasons took on a decreasing trend, and the intra-annual distribution of water and sediment discharges tended to be uniform. The evolution process from deposition to erosion occurred at the -10 m and -20 m isobaths of the subaqueous delta. The enhanced annual water and sediment discharges had a silting-up effect on the delta, and the effect of sediment was greater than that of water. Based on data analysis, empirical curves were built to present the relationships between the water and sediment discharges over a year or in dry and flood seasons and the erosion/deposition rates in typical regions of the suhaqueous delta, whose evolution followed the pattern of silting in flood seasons and scouring in dry seasons. Notably, the Three Gorges Dam has changed the distribution processes of water and sediment discharges, and the dam's regulating and reserving functions can benefit the subaqueous delta deposition when the annual water and sediment discharges are not affected. 展开更多
关键词 water discharge sediment discharge seasonal change DELTA Yangtze Estuary
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乙肝代偿期肝硬化患者高风险食管胃底静脉曲张预测模型的构建:一项病例对照研究 被引量:3
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作者 荣亚梅 张洪文 +2 位作者 张君虹 刘澎 高海德 《世界华人消化杂志》 CAS 2022年第3期152-157,共6页
背景上消化道内镜检查是判断肝硬化患者食管胃底静脉曲张的金标准.对于高风险食管胃底静脉曲张尚缺乏有效无创预测模型.目的构建并验证乙肝代偿期肝硬化患者发生高风险食管胃底静脉曲张的模型.方法回顾性分析2018-01/2020-12于天津市北... 背景上消化道内镜检查是判断肝硬化患者食管胃底静脉曲张的金标准.对于高风险食管胃底静脉曲张尚缺乏有效无创预测模型.目的构建并验证乙肝代偿期肝硬化患者发生高风险食管胃底静脉曲张的模型.方法回顾性分析2018-01/2020-12于天津市北辰医院和武警特色医学中心收治的276例乙肝代偿期肝硬化患者常规实验室检查和超声检查临床资料.其中81例高风险静脉曲张患者,195例非高风险静脉曲张.采用Logistic回归分析影响乙肝代偿期肝硬化患者发生高风险食管胃底静脉曲张的独立危险因素,并使用这些因素构建预测模型.使用受试者工作特征曲线(receiver operating characteristic,ROC)验证所构建模型的预测效能.结果Logistic回归显示白蛋白(albumin,ALB)水平(OR=0.825,95%CI:0.779-0.873,P=0.000)、血小板(platelet,PLT)水平(OR=0.934,95%CI:0.895-0.975,P=0.001)、门静脉宽度(OR=1.481,95%CI:1.141-1.922,P=0.002)是乙肝代偿期肝硬化患者高风险静脉曲张发生的危险因素.预测模型:Y=-0.192×ALB(g/L)-0.068×PLT计数(10^(9)/L)+0.39×门静脉宽度(mm)+6.87.该模型预测高风险食管胃底静脉曲张的ROC曲线下面积为0.976,最佳诊断切点为0.767,此时的敏感度为0.968,特异度为0.882.结论基于PLT、ALB和门静脉宽度的高风险食管胃底静脉曲张预测模型具有较高诊断效能,值得今后进一步研究和推广. 展开更多
关键词 食管胃底静脉曲张 肝硬化 预测 上消化道内镜
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Unsteady heat and mass transfer in MHD flow over an oscillatory stretching surface with Soret and Dufour efects
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作者 Lian-Cun Zheng Xin Jin +1 位作者 Xin-Xin zhang jun-hong zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第5期667-675,共9页
In this paper, we study the unsteady coupled heat and mass transfer of two-dimensional MHD fluid over a moving oscillatory stretching surface with Soret and Dufour effects. Viscous dissipation effects are adopted in t... In this paper, we study the unsteady coupled heat and mass transfer of two-dimensional MHD fluid over a moving oscillatory stretching surface with Soret and Dufour effects. Viscous dissipation effects are adopted in the energy equation. A uniform magnetic field is applied vertically to the flow direction. The governing equations are reduced to non-linear coupled partial differential equations and solved by means of homotopy analysis method (HAM). The effects of some physical parameters such as magnetic parameter, Dufour number, Soret number, the Prandtl num- ber and the ratio of the oscillation frequency of the sheet to its stretching rate on the flow and heat transfer characteristics are illustrated and analyzed. 展开更多
关键词 Viscous conducted fluid Magnetic field Os- cillatory stretching surface Heat and mass transfer HAM solution
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Misalignment analysis of journal bearing influenced by asymmetric deflection,based on a simple stepped shaft model 被引量:11
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作者 Zhen-peng HE jun-hong zhang +2 位作者 Wei-song XIE Zhou-yu LI Gui-chang zhang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2012年第9期647-664,共18页
The effects of journal misalignment on a journal bearing caused by an asymmetric rotor structure are presented in this study.A new model considering the asymmetric deflection is applied.Also,the thermo-hydrodynamic of... The effects of journal misalignment on a journal bearing caused by an asymmetric rotor structure are presented in this study.A new model considering the asymmetric deflection is applied.Also,the thermo-hydrodynamic of the oil film in the journal bearing and straightforward elasticity theory are considered in the analysis.Based on the structure stiffness equivalent characteristic,a simple stepped shaft can reflect the entire complex structure model.The existing lubrication model,which does not consider this angle component,is not very precise for journal bearings.Film pressure,misalignment angle,velocity field,oil leakage,and temperature field were calculated and compared in the journal bearing analysis.The results indicate that bearing performances are greatly affected by misalignment caused by the asymmetric structure.A simple stepped shaft can effectively represent a misaligned journal bearing in a rotor-bearing system. 展开更多
关键词 错误排列 走的柄 不对称的结构 杂志适用
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Application of complete ensemble intrinsic time-scale decomposition and least-square SVM optimized using hybrid DE and PSO to fault diagnosis of diesel engines 被引量:7
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作者 jun-hong zhang Yu LIU 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第2期272-286,共15页
针对固有时间尺度分解算法的模态混叠问题和最小二乘支持向量机的参数优化问题,本文提出了一种新的基于完备集合固有时间尺度分解和混合差分进化和粒子群算法优化最小二乘支持向量机的柴油机故障诊断方法。该方法主要包括以下几个步骤:... 针对固有时间尺度分解算法的模态混叠问题和最小二乘支持向量机的参数优化问题,本文提出了一种新的基于完备集合固有时间尺度分解和混合差分进化和粒子群算法优化最小二乘支持向量机的柴油机故障诊断方法。该方法主要包括以下几个步骤:首先,为解决固有时间尺度分解算法的模态混叠问题,提出了一种完备集合固有时间尺度分解算法。随后,利用完备集合固有时间尺度分解算法将非平稳的柴油机振动信号分解为一系列平稳的旋转分量和残差信号。然后,提取了前几阶旋转分量的三类典型的时频特征,包括奇异值、旋转分量能量和能量熵、AR模型参数,作为故障特征。最后,提出了混合差分进化和粒子群算法对最小二乘支持向量机的参数进行优化的方法,并通过将故障特征输入训练好的最小二乘支持向量机模型实现故障诊断。仿真和实验结果表明提出的故障诊断方法可以克服固有时间尺度分解的模态混叠问题,而且能够准确的识别柴油机故障。 展开更多
关键词 柴油机 故障诊断 完备集合固有时间尺度分解 最小二乘支持向量机 混合差分进化和粒子群优化算法
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Toward superior lithium/sodium storage performance: design and construction of novel TiO_(2)-based anode materials 被引量:4
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作者 Pan-Pan Peng Yu-Rong Wu +4 位作者 Xue-Zhong Li jun-hong zhang Yan-Wei Li Ping Cui Ting-Feng Yi 《Rare Metals》 SCIE EI CAS CSCD 2021年第11期3049-3075,共27页
TiO_(2)-based materials have been considered as one of most promising alternatives for high-performance Li(Na)-ion batteries because of the low cost,simple composition,easy synthesis,good environmental protection,exce... TiO_(2)-based materials have been considered as one of most promising alternatives for high-performance Li(Na)-ion batteries because of the low cost,simple composition,easy synthesis,good environmental protection,excellent safety and relatively high specific capacity.Nonetheless,the inferior electronic conductivity and poor ion diffusion coefficients are the biggest bottlenecks that restrict the popular application.Much effort has been focused on resolving these problems toward large-scale applications,and numerous significant advances have been accomplished.In the present work,a comprehensive overview of structure characteristics,electrochemical reaction mechanism and modification strategies of TiO_(2)-based materials was presented.The recent advances of various efficient ways for improving conductivity,Li(Na)storage capacity,rate capability and cycle stability are systematically summarized,including surface engineering,constructing composite and element doping,etc.Constructing TiO_(2)-based materials with novel porous heterogeneous core-shell structures have been regarded as one of the most effective ways to resolve these challenges.Finally,the future research directions and development prospects of TiO_(2)-based anode materials used in the manufacture of high-performance Li(Na)-ion batteries are prospected.This review can provide important comprehension for the construction and optimization of highperformance of TiO_(2)-based anode materials. 展开更多
关键词 TiO_(2) Anode material Li-ion battery Na-ion battery Electrochemical performance
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Functional Characterization of Mi, a Root-knot Nematode Resistance Gene from Tomato ( Lycopersicon esculentum L.) 被引量:3
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作者 Ru-Gang Chen Li-Ying zhang +5 位作者 jun-hong zhang Wei zhang Xue Wang Bo Ouyang Han-Xia Li Zhi-Biao Ye 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2006年第12期1458-1465,共8页
Root-knot nematodes (Meloidogyne spp.) cause major economic damage to numerous crop species around the world. Plant resistance is the most important attribute that is able to suppress invasion by the rootknot nemato... Root-knot nematodes (Meloidogyne spp.) cause major economic damage to numerous crop species around the world. Plant resistance is the most important attribute that is able to suppress invasion by the rootknot nematodes. In the present study, a candidate root-knot nematode resistance gene (Mi) was isolated from the resistant tomato (Lycopersicon esculentum L.) line RN-1. Expression profiling analysis revealed that this gene was expressed specifically in the roots, stems, and leaves, but not in the flowers or fruits. To verify the real function of this candidate gene, both sense and inteference RNA (RNAi) vectors were constructed. We obtained 31 transgenic plants with between one and seven copies of T-DNA inserts of sense Mi from two nematode-susceptible tomato cultivars as assayed by polymerase chain reaction (PCR) and Southern blotting analysis. Reverse transcription-PCR analysis revealed that expression levels of the Mi gene varied in different transgenic plants. Nematode assays showed that the resistance to root-knot nematodes was significantly improved in some transgenic lines compared with untransformed susceptible controls and that the resistance was heritable in selfed progeny. Loss of function via RNAi further confirmed the role of the Mi gene and the original resistant lines became susceptible to root-knot nematodes. 展开更多
关键词 Mi gene OVEREXPRESSION RNAI root-knot nematode TOMATO
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基于数值算法的车辆动力学模型及数值求解方法精度的对比研究(英文) 被引量:3
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作者 Peng GUO jun-hong zhang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2017年第5期393-412,共20页
目的:通过采用不同数值方法求解不同的车辆动力学模型,为车辆动力学模型研究提供参考;结合正交试验和多目标优化算法来分析各个参数对车辆性能的影响权重,采用多目标优化算法进行车辆动力学多目标优化分析,为车辆的设计提供参考依据。... 目的:通过采用不同数值方法求解不同的车辆动力学模型,为车辆动力学模型研究提供参考;结合正交试验和多目标优化算法来分析各个参数对车辆性能的影响权重,采用多目标优化算法进行车辆动力学多目标优化分析,为车辆的设计提供参考依据。创新点:研究不同数值方法的求解精度,为车辆动力学求解方法提供新途径;采用正交试验设计研究车辆各参数的影响权重,为车辆设计提供参考;采用多目标优化算法设计车辆,能兼顾车辆多个方面的性能。方法:采用不同动力学求解算法、正交试验设计和多目标优化分析方法。结论:1.基于不同数值求解算法的研究表明,Hamming法要优于Newmark法和有限差分法,四阶Hamming法的精度不如龙格库塔法;2.正交试验可得到各参数对车辆动力学的影响权重,但忽略了参数间的交互效应;3.经过多目标优化设计,衡量车辆振动性能的两个指标分别减少了7.22%和6.82%。 展开更多
关键词 车辆 Hamming法 龙格库塔法 数值算法 动力仿真
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Interconnected Bi_(5)Nb_(3)O_(15)@CNTs network as high-performance anode materials of Li-ion battery 被引量:3
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作者 Xue-Zhong Li Nan zhang +5 位作者 Yu-Rong Wu Qin-Zhi Lai Yan-Rong Zhu jun-hong zhang Ping Cui Ting-Feng Yi 《Rare Metals》 SCIE EI CAS CSCD 2022年第10期3401-3411,共11页
In this work,the facile carbon nanotubes(CNTs) modulation strategy was successfully used to fabricate Bi_(5) Nb_(3) O_(15)@CNTs composites as anode materials for lithium-ion battery by a simple solid-state route.The i... In this work,the facile carbon nanotubes(CNTs) modulation strategy was successfully used to fabricate Bi_(5) Nb_(3) O_(15)@CNTs composites as anode materials for lithium-ion battery by a simple solid-state route.The introduction of CNTs does not change the structure of the Bi_(5) Nb_(3) O_(15) materials,the Bi_(5) Nb_(3) O_(15) particles are decorated on a three-dimensional CNTs network,and the high conductive network promotes transfer of electron/ion and relieve the volume change of Bi_(5) Nb_(3) O_(15).The Bi_(5) Nb_(3) O_(15)@CNTs(8 wt%) electrode shows a superior rate capability with charge(discharge) capacities of 490(898.7),379.1(401.6),311.3(326.9),276.5(285.5) and 243.4(252)mAh·g^(-1) at 50,100,200,300 and 500 mA·g^(-1),respectively.However,the Bi_(5) Nb_(3) O_(15) only shows charge(discharge) capacities of 431(772.6),278.6(309.9),193.1(213.7),160.8(171.1),129.9(139.1) mAh·g^(-1) at the corresponding rates,respectively.The excellent rate capability of Bi_(5) Nb_(3) O_(15)@CNTs can be ascribed to the homogeneous distribution of Bi_(5) Nb_(3) O_(15) particles in the CNTs conductive network and the enhancement of conductivity.Hence,the CNTs modulation can be considered as an effective strategy to enhance electrochemical performances of Bi_(5) Nb_(3) O_(15) materials. 展开更多
关键词 Bi_(5)Nb_(3)O_(15) Carbon nanotubes(CNTs) Anode Li-ion battery(LIB)
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Non-isothermal thermogravimetric investigation on mutual effect between bituminite and anthracite in blends for blast furnace injection 被引量:1
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作者 Yun-fei Wu Qing-hai Pang +3 位作者 Zhi-jun He Teng-fei Song Wen-long Zhan jun-hong zhang 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2019年第8期818-828,共11页
In order to clarify the mutual effect between bituminite and anthracite in blends during industrial combustion, the influence of particle size and heating rate as well as oxygen concentration in atmosphere was analyze... In order to clarify the mutual effect between bituminite and anthracite in blends during industrial combustion, the influence of particle size and heating rate as well as oxygen concentration in atmosphere was analyzed. The results of non-isothermal thermogravimetric analysis indicated that the combustion behavior of blends was of great difference though blends were prepared with the same volatile content of 20%. The catalysis of bituminite to anthracite changed with the thermal and kinetic condition of combustion reaction, and consequently, blends with different collocations were suitable for various combustion environments. Superior combustion properties of some blends were achieved at high heating rates, while others might react faster under high oxygen-enriched atmosphere. Simultaneously, the volume model and unreacted core model as well as random pore model were introduced to fit the experimental data. The kinetic calculation results showed that the combustion of blends at different heating rates all agreed better with that of random pore model in comparison with the other two models, while the apparent activation energy of samples all decreased with the increase in heating rate. The similarity of functional group structure between bituminite and anthracite is closely related to the accordance in com-bustion stage of bituminite and anthracite in blends. 展开更多
关键词 Pulverized COAL injection COAL BLEND Mutual EFFECT Kinetics Activation energy Bituminite ANTHRACITE
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不对中故障下带挤压油膜阻尼器的滚动轴承转子系统的动力学分析(英文) 被引量:1
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作者 Liang MA jun-hong zhang +2 位作者 Jie-wei LIN Jun WANG Xin LU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2016年第8期614-631,共18页
目的:工业的不断发展对航空发动机、泵、燃气轮机等旋转机械的动力性能提出了更高的要求。转子系统是旋转机械的重要组成部分。复杂的转子系统在高速运转时会产生故障和非线性振动,从而影响系统的可靠性。因此,开展转子系统的非线性动... 目的:工业的不断发展对航空发动机、泵、燃气轮机等旋转机械的动力性能提出了更高的要求。转子系统是旋转机械的重要组成部分。复杂的转子系统在高速运转时会产生故障和非线性振动,从而影响系统的可靠性。因此,开展转子系统的非线性动力性研究,研究转子系统在高速运转时的非线性响应及其抑制作用对转子系统的设计和故障诊断具有重要的意义。创新点:1.在建模的时候考虑转子系统的实际结构,在不对中模型中引入齿式联轴器啮合力,在滚动轴承模型中考虑弹流润滑影响;2.探究挤压油膜阻尼器参数对转子系统非线性特性抑制的影响,总结其变化规律。方法:1.基于Hertz接触和弹流润滑理论,建立滚动轴承动力学模型,同时考虑齿式联轴器齿之间的啮合力,建立不对中故障下的齿式联轴器啮合力模型,并在此基础上,根据转子系统的支撑形式,建立0-2-1支撑的转子动力学模型;2.开展转子动力学实验,验证模型的准确性并分析不对中量对系统频谱特性的影响;3.在分析不对中故障非线性特性的基础上,研究挤压油膜阻尼器参数对于非线性特性抑制的作用。结论:1.齿式联轴器啮合作用和滚动轴承的弹流润滑对不对中故障下转子系统的失稳产生一定的影响,润滑会导致系统发生分岔的窗口推迟;2.对于转子系统的弹性支撑,其一阶临界转速和振幅随着刚度的增大而增大,选择合适的刚度有利于转子系统的稳定运行;3.挤压油膜阻尼器的参数对转子系统故障引起的非线性具有较好的抑制作用,其作用的大小取决于不对中量和挤压油膜阻尼器的油膜间隙的耦合,合理地调节油膜间隙有助于增大系统的稳定区间范围。 展开更多
关键词 挤压油膜阻尼器 齿式联轴器 滚动轴承 弹流润滑 非线性动力学 不对中故障
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基于PC,UDS和改进AHP的柴油机噪声品质综合评价方法(英文) 被引量:1
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作者 Wen-yun HE jun-hong zhang Jian WANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2017年第7期531-544,共14页
目的:提出柴油机噪声品质综合评价方法,解决产品总体噪声品质择优排序问题。创新点:在噪声品质综合评价模型的研究中,将均匀设计抽样与层次分析法相结合,提出一种考虑多因素、多水平的噪声品质主观综合评价GPC-UDS-AHP方法,通过对少量... 目的:提出柴油机噪声品质综合评价方法,解决产品总体噪声品质择优排序问题。创新点:在噪声品质综合评价模型的研究中,将均匀设计抽样与层次分析法相结合,提出一种考虑多因素、多水平的噪声品质主观综合评价GPC-UDS-AHP方法,通过对少量的声样本进行主观评价得到声品质综合评价结果;提出基于偏好序和Bradley-Terry模型的权重计算方法,避免了1-9标度法主观性强和一致性难以满足要求的问题。方法:针对传统的成对比较法难以在声品质主观评价试验中获得评价对象整体感受择优排序的不足,结合均设计抽样法"均匀分散"的特点,提出一种基于分组成对比较法的柴油机声品质主观综合评价方法,确定适合于柴油机声品质主观评价的结构及层次划分,提出基于偏好序和Bradley-Terry模型的各级指标权重计算方法。以采集到的某3款柴油机共375个噪声样本为评价对象,分别利用该方法和等级评分法计算得出3款柴油机的声品质评价综合值。结论:提出的柴油机声品质主观综合评价GPC-UDS-AHP方法可在有效地维持成对比较主观评价试验实施范围的情况下,准确地得到柴油机声品质整体主观感受评价得分的择优排序,可用于实施不同柴油机或N次改进试验的声品质比较和评判。 展开更多
关键词 柴油机 声品质 均匀设计抽样 成对比较法 层次分析法
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Inter-asperity cavitation for misalignment journal lubrication problem based on mass-conservative algorithm
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作者 Zhen-peng HE jun-hong zhang +4 位作者 Zhou-yu LI Lin BA Gui-chang zhang Kai-nan WANG Xing LU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2013年第9期642-656,共15页
Journal misalignment is common in journal bearings. When severe journal misalignment takes place, it affects nearly all aspects of bearing performance. This paper provided a comprehensive analysis of misaligned journa... Journal misalignment is common in journal bearings. When severe journal misalignment takes place, it affects nearly all aspects of bearing performance. This paper provided a comprehensive analysis of misaligned journal bearings based on two different mass-conservative models which appropriately took into account film rupture and reformation. The lubrication characteristics and performance parameters including the cavitation zones, pressure distribution, density distribution, oil leakage, load capacity, moment, and attitude angle were compared with the traditional lubrication model. The results showed that cavitation has great effect on bearing performances, especially when the surface roughness is large. Therefore, it is necessary to consider the effects of journal misalignment alongside inter-asperity cavitation theory in the design and analyses of journal bearings. 展开更多
关键词 表面粗糙度 润滑模型 保守 轴颈轴承 算法 大众 杂志 基础
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Construction of Na_(2)Li_(2)Ti_(6)O_(14)@LiAlO_(2)Composites as Anode Materials of Lithium-Ion Battery with High Performance
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作者 Nan zhang Ze-Chen Lv +3 位作者 Yu-Shen Zhao jun-hong zhang Yan-Rong Zhu Ting-Feng Yi 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2022年第12期2047-2056,共10页
In this work,we construct Na_(2)Li_(2)Ti_(6)O_(14)@LiAlO_(2)(NLTO-L)composites by a simple ball milled process and post-calcination in air atmosphere to improve the electrochemical performance.The thickness of the LiA... In this work,we construct Na_(2)Li_(2)Ti_(6)O_(14)@LiAlO_(2)(NLTO-L)composites by a simple ball milled process and post-calcination in air atmosphere to improve the electrochemical performance.The thickness of the LiAlO_(2)coating layer is approximate2 nm.The morphology and particle size of Na_(2)Li_(2)Ti_(6)O_(14)are not dramatically altered after LiAlO_(2)coating.All samples display similar particles with a size range from 150 to 500 nm.The LiAlO_(2)coating can supply fast charge transmission paths with good insertion/extraction dynamics of lithium ions and provide an excellent rate performance and cycle performance of as-prepared Na_(2)Li_(2)Ti_(6)O_(14)@LiAlO_(2)anodes.Therefore,LiAlO_(2)coating efficiently enhances the rate performance and cycle performance of Na_(2)Li_(2)Ti_(6)O_(14)anode,even at large current densities.As a result,Na_(2)Li_(2)Ti_(6)O_(14)@LiAlO_(2)(5 wt%)reveals remarkable rate properties with reversible charge capacity of 238.7,214.7,185.8,168.5 and 139.8 mAh g^(-1)at 50,100,200,300 and 500 mA g^(-1),respectively.Na_(2)Li_(2)Ti_(6)O_(14)@LiAlO_(2)(5 wt%)also possesses a good cycle performance with a de-lithiation capacity of 166.5 mAh g-1 at 500 mA g^(-1)after 200 cycles.Nonetheless,the corresponding de-lithiation capacity of pure Na_(2)Li_(2)Ti_(6)O_(14)is only 140.1 mAh g^(-1).Consequently,LiAlO_(2)coating is efficeient approach to enhance the electrochemical performances of Na_(2)Li_(2)Ti_(6)O_(14). 展开更多
关键词 Li-ion batteries Na_(2)Li_(2)Ti_(6)O_(14) LiAlO_(2) Anode material Electrochemical properties
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PPy-Encapsulated Na_(2)Li_(2)Ti_(6)O_(14) Composites as High-Performance Anodes for Li-Ion Battery
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作者 Fan-Fan Wang Nan zhang +3 位作者 Ze-Chen Lv Yan-Rong Zhu jun-hong zhang Ting-Feng Yi 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2022年第11期1873-1881,共9页
Na_(2)Li_(2)Ti_(6)O_(14) as a reliable anode material is becoming a hopeful candidate for Li-ion battery.Nevertheless,the pristine Na_(2)Li_(2)Ti_(6)O_(14) usually suffer from bad rate performance and poor cycling sta... Na_(2)Li_(2)Ti_(6)O_(14) as a reliable anode material is becoming a hopeful candidate for Li-ion battery.Nevertheless,the pristine Na_(2)Li_(2)Ti_(6)O_(14) usually suffer from bad rate performance and poor cycling stability under high current due to limited diffusion kinetics and poor electrical conductivity.Here,the PPy-coated Na_(2)Li_(2)Ti_(6)O_(14) composites are successfully obtained via the solid-state method and followed by chemical oxidation process in the first time.The results of tests prove that the Na_(2)Li_(2)Ti_(6)O_(14)@PPy composites have better electrochemical performance than the bare Na_(2)Li_(2)Ti_(6)O_(14) because of the excellent electrical conductivity and the special macromolecular architecture of PPy.In particular,the Na_(2) Li_(2) Ti_(6) O_(14) @PPy(4 wt%)exhibits excellent charge capacities of about 223.2,218.0,200.8,184.3 and 172.6 mAh g^(-1) at 50,100,200,300 and500 mA g^(-1),respectively,revealing the best rate capability of all electrode materials.The Na_(2)Li_(2)Ti_(6)O_(14)@PPy(4 wt%)not only has the highest charge capacity under 0.5 mA g^(-1),but also has the highest capacity retention of 85.12%among all samples after 100 loops.Hence,the PPy coating is known as a promising way to improve the electrochemical property of Na_(2)Li_(2)Ti_(6)O_(14).The PPy-coated Na_(2)Li_(2)Ti_(6)O_(14) demonstrates the great prospect as promising negative materials for Li-ion batteries. 展开更多
关键词 Li-ion battery Anode material Na_(2)Li_(2)Ti_(6)O_(14) PPy coating Electrochemical property
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Kinetic study on co-combustion of pulverized anthracite and bituminite for blast furnace injection
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作者 Li-chun Yang Qing-hai Pang +3 位作者 Zhi-jun He jun-hong zhang Wen-long Zhan Nan Lü 《Journal of Iron and Steel Research(International)》 SCIE EI CSCD 2021年第8期949-964,共16页
Combustion behavior of single pulverized coals(PCs)and co-combustion characteristics of anthracite(AT)and bituminite(BT)blends with 20 wt.%volatile were studied by thermogravimetric experiments.The results indicated t... Combustion behavior of single pulverized coals(PCs)and co-combustion characteristics of anthracite(AT)and bituminite(BT)blends with 20 wt.%volatile were studied by thermogravimetric experiments.The results indicated that reaction characteristics of PCs were closely related to their functional group structure and consequently,the pyrolysis of PCs with highly active functional groups initiated at lower temperatures.It was also noticed that the discrepancy of functional group structures between AT and BT might impair their interaction during combustion.The early exhaust of BT at low temperatures would possibly lead to an independent combustion of volatile and residual carbon and eventually the inefficient combustion of their blend.However,the mixing of AT and BT with similar functional group structures was more likely to achieve blends with superior combustion property.Simultaneously,non-isothermal kinetic analysis mani-fested that the combustion of blends followed random pore model(RPM),and therefore,the parameters calculated by RPM were more accurate to describe their combustion behavior.The kinetic calculation results showed that the activation energy required for decomposition of blends in early combustion stage was much lower owing to the excellent activity of volatile,while residual carbon with stable aromatic hydrocarbon demanded more energy to initiate its combustion. 展开更多
关键词 Blast furnace Pulverized coal Coal blend Non-isothermal combustion Kinetic analysis
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