期刊文献+
共找到80篇文章
< 1 2 4 >
每页显示 20 50 100
Alcohol-dispersed polymer complex as an effective and durable interface modifier for n-i-p perovskite solar cells
1
作者 Chang Shi Jiangling Li +8 位作者 Shuping Xiao Ziyi Wang wuchen Xiang rui wu Yang Liu Yinhua Zhou Weijun Ke Guojia Fang Pingli Qin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期243-252,I0007,共11页
Abundant interfacial defects remain a significant challenge that hampers both the efficiency and stability of perovskite solar cells(PSCs).Herein,an alcohol-dispersed conducting polymer complex,denoted as PEDOT:F(Poly... Abundant interfacial defects remain a significant challenge that hampers both the efficiency and stability of perovskite solar cells(PSCs).Herein,an alcohol-dispersed conducting polymer complex,denoted as PEDOT:F(Poly(3,4-ethylene dioxythiophene):Perfluorinated sulfonic acid ionomers),is introduced into the interface between perovskite and hole transporting layer in regular-structured PSCs.PEDOT:F serves as a multi-functional interface layer(filling grain boundaries and covering perovskite's grain-surface)to achieve a robust interaction with organic groups within perovskites,which could induce a structural transformation of PEDOT to increase its conductivity for the efficient hole-transport.Furthermore,the strong interaction between PEDOT and perovskites could promote an effective coupling of undercoordinated Pb~(2+)ions with the lone electron pairs near O&S atoms in PEDOT molecules,thereby enhancing defect passivation.Additionally,PEDOT:F with inherent hydrophobic properties prevents effectively moisture invasion into perovskites for the improved long-term stability of the PSCs.Consequently,the PEDOT:F-based PSCs achieved a champion efficiency of 24.81%,and maintained ca.92%of their initial efficiency after 7680 h of storage in a dry air environment,accompanied by the enhanced photothermal stability. 展开更多
关键词 Alcohol-dispersed conducting polymer complex Interface passivation Grain boundaries Device stability Perovskite solar cells
下载PDF
PtZn nanoparticles supported on porous nitrogen-doped carbon nanofibers as highly stable electrocatalysts for oxygen reduction reaction
2
作者 Lei Zhao Jinxia Jiang +6 位作者 Shuhao Xiao Zhao Li Junjie Wang Xinxin Wei Qingquan Kong Jun Song Chen rui wu 《Nano Materials Science》 EI CAS CSCD 2023年第3期329-334,共6页
The oxygen reduction reaction(ORR)electrocatalytic activity of Pt-based catalysts can be significantly improved by supporting Pt and its alloy nanoparticles(NPs)on a porous carbon support with large surface area.Howev... The oxygen reduction reaction(ORR)electrocatalytic activity of Pt-based catalysts can be significantly improved by supporting Pt and its alloy nanoparticles(NPs)on a porous carbon support with large surface area.However,such catalysts are often obtained by constructing porous carbon support followed by depositing Pt and its alloy NPs inside the pores,in which the migration and agglomeration of Pt NPs are inevitable under harsh operating conditions owing to the relatively weak interaction between NPs and carbon support.Here we develop a facile electrospinning strategy to in-situ prepare small-sized PtZn NPs supported on porous nitrogen-doped carbon nanofibers.Electrochemical results demonstrate that the as-prepared PtZn alloy catalyst exhibits excellent initial ORR activity with a half-wave potential(E_(1/2))of 0.911 V versus reversible hydrogen electrode(vs.RHE)and enhanced durability with only decreasing 11 mV after 30,000 potential cycles,compared to a more significant drop of 24 mV in E_(1/2)of Pt/C catalysts(after 10,000 potential cycling).Such a desirable performance is ascribed to the created triple-phase reaction boundary assisted by the evaporation of Zn and strengthened interaction between nanoparticles and the carbon support,inhibiting the migration and aggregation of NPs during the ORR. 展开更多
关键词 PtZn alloy Porous nitrogen-doped carbon nanofibers ELECTROSPINNING Oxygen reduction reaction
下载PDF
Exact solution of slow quench dynamics and nonadiabatic characterization of topological phases
3
作者 邬睿 房盼攀 +1 位作者 孙辰 李福祥 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期171-180,共10页
Previous studies have shown that the bulk topology of single-particle systems can be captured by the band inversion surface or by the spin inversion surface emerging on the time-averaged spin polarization.Most of the ... Previous studies have shown that the bulk topology of single-particle systems can be captured by the band inversion surface or by the spin inversion surface emerging on the time-averaged spin polarization.Most of the studies,however,are based on the single-particle picture even though the systems are fermionic and multi-bands.Here,we study the slow quench dynamics of topological systems with all the valence bands fully occupied,and show that the concepts of band inversion surface and spin inversion surface are still valid.More importantly,the many-particle nonadiabatic quench dynamics is shown to be reduced to a new and nontrivial three-level Landau-Zener model.This nontrivial three-level Landau-Zener problem is then solved analytically by applying the integrability condition and symmetry considerations,and thus adds a new member to the few models that are exactly solvable.Based on the analytical results,the topological spin texture revealed by the time-averaged spin polarization can be applied to characterize the bulk topology and thus provides a direct comparison for future experiments. 展开更多
关键词 Landau-Zener slow quench NONADIABATIC
下载PDF
聚碳酸酯合成技术研究进展 被引量:15
4
作者 曾伟华 刘俊逸 +4 位作者 谢海生 邹永春 吴芮 张爱民 武建勋 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第7期183-190,共8页
概要地介绍了聚碳酸酯的合成技术,重点对非光气法进行了介绍,比较了非光气法相对于光气法的优缺点。按照不同的合成路径对非光气法进行了全面阐述,阐明了双酚A聚碳酸酯非光气化、低碳、减排的绿色和可持续发展的化工工艺技术是聚碳酸酯... 概要地介绍了聚碳酸酯的合成技术,重点对非光气法进行了介绍,比较了非光气法相对于光气法的优缺点。按照不同的合成路径对非光气法进行了全面阐述,阐明了双酚A聚碳酸酯非光气化、低碳、减排的绿色和可持续发展的化工工艺技术是聚碳酸酯合成技术发展的方向。另一方面,共聚聚碳酸酯和脂肪族聚碳酸酯由于其有别于传统聚碳酸酯的阻燃、绿色、环保以及可降解等性能,逐渐受到各国研究人员的重视。 展开更多
关键词 聚碳酸酯 碳酸二甲酯 碳酸二苯酯 二氧化碳 合成
下载PDF
填充油组成对充油SEBS体系力学性能、热性能及微观结构的影响 被引量:3
5
作者 史晓滔 辛秀婷 +5 位作者 谢海生 教震 吴芮 熊春珠 张爱民 武建勋 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第10期108-114,共7页
自制了一系列运动黏度基本保持不变、组成有规律连续变化的填充油,首次系统研究了油品组成对充油聚苯乙烯-乙烯/丁烯-苯乙烯(SEBS)体系结构与性能的影响,分析了油品在多相的SEBS中的相平衡和"再分配"规律,揭示了油品组成对充... 自制了一系列运动黏度基本保持不变、组成有规律连续变化的填充油,首次系统研究了油品组成对充油聚苯乙烯-乙烯/丁烯-苯乙烯(SEBS)体系结构与性能的影响,分析了油品在多相的SEBS中的相平衡和"再分配"规律,揭示了油品组成对充油体系结构与性能的影响机制。研究发现,随着油品中环氧油含量(CN)的增加(由27.4%到50.4%),动态力学热分析显示TgPS由108.6℃降至98.03℃,小角X射线散射结果显示软硬相电子密度差逐渐降低,表明环烷烃分子进入软硬相之间,增塑聚苯乙烯(PS)相与其产生相互作用,充油体系起始剪切黏度由9361.30 Pa·s降至4562.71 Pa·s,流动性显著增大;PS相间距由38.929 nm增至40.329 nm,油分子逸出通道加宽,迁出率增大(由0.266%增至2.858%),体系热失重性能降低(Tonset由289.0℃降至241.7℃)。在CN为33.2%时,充油SEBS的拉伸强度达到极大值(11.62 MPa),而伸长率随CN变化基本保持不变(1000%左右)。 展开更多
关键词 填充油 聚苯乙烯-乙烯/丁烯-苯乙烯 相互作用 结构 性能
下载PDF
聚碳酸酯反复加工稳定性与结构的关系 被引量:4
6
作者 谢海生 曾伟华 +3 位作者 吴芮 邹永春 史晓滔 武建勋 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第4期42-48,共7页
通过对4种分别采用光气法和熔融酯交换法生产的、具有代表性的国产和进口聚碳酸酯(PC)的物理力学性能及反复加工后的性能稳定性进行了研究。发现不同聚碳酸酯(PC)原料本身的拉伸强度、断裂伸长率、屈服应力、冲击强度和熔体流动速率并... 通过对4种分别采用光气法和熔融酯交换法生产的、具有代表性的国产和进口聚碳酸酯(PC)的物理力学性能及反复加工后的性能稳定性进行了研究。发现不同聚碳酸酯(PC)原料本身的拉伸强度、断裂伸长率、屈服应力、冲击强度和熔体流动速率并无明显差异,但4种牌号PC的反复加工稳定性差异显著。通过凝胶渗透色谱和核磁共振碳谱对不同PC的分子结构和相对分子质量及其分布进行了表征分析,结合Instron万能材料试验机等的测试结果,首次发现,当相对分子质量相近的PC中小分子链/大分子链所占比例越高、分子链“离散性”越大,其反复加工后物理力学性能的稳定性也越差;PC中的支化链和芳基酮含量越高其反复加工稳定性也越差;熔融酯交换法生产的PC中因Fries重排而存在支化链和芳基酮结构,光气法PC中未检测到支化链和芳基酮。 展开更多
关键词 聚碳酸酯 物理力学性能 反复加工稳定性 结构表征
下载PDF
Hierarchically porous nitrogen-doped carbon as cathode for lithium–sulfur batteries 被引量:9
7
作者 rui wu Siguo Chen +5 位作者 Jianghai Deng Xun Huang Yujie Song ruiyi Gan Xiaoju Wan Zidong Wei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第6期1661-1667,共7页
Porous nitrogen-doped carbon is an especially promising material energy storage due to its excellentconductivity, stable physicochemical properties, easy processability, controllable porosity and low price.Herein, we ... Porous nitrogen-doped carbon is an especially promising material energy storage due to its excellentconductivity, stable physicochemical properties, easy processability, controllable porosity and low price.Herein, we reported a novel well-designed hierarchically porous nitrogen-doped carbon (HPNC) via acombination of salt template (ZnC12) and hard template (SiO2) as sulfur host for lithium-sulfur batter-ies. The low-melting ZnC12 is boiled off and leaves behind micropores and small size mesopores duringpyrolysis process, while the silica spheres are removed by acid leaching to generate interconnected 3Dnetwork of macropores. The HPNC-S electrode exhibits an initial specific capacity of 1355 mAh g^-l at 0.IC (IC= 1675 mAh g^-1 ), a high-rate capability of 623 mAh g-l at 2 C, and a small decay of 0.13% per cycleover 300 cycles at 0.2 C. This excellent rate capability and remarkable long-term cyclability of the HPNC-Selectrode are attributed to its hierarchical porous structures for confining the soluble lithium polysulfideas well as the nitrogen doping for high absorbability of lithium polysulfide. 展开更多
关键词 Hierarchically porous structure Nitrogen-doped carbon Lithium-sulfur batteries
下载PDF
充油SEEPS/SEBS的力学性能和动态力学性能与结构的关系
8
作者 吴芮 教震 +6 位作者 刘俊逸 姚徽疆 胡贝利 熊春珠 甄新平 张爱民 武建勋 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第6期133-139,共7页
对具有代表性的多种SEEPS和SEBS进行了结构分析和相对分子质量检测,筛选出化学结构不同但苯乙烯含量相同且相对分子质量接近而具有可比性的SEEPS Kuraray-4055和SEBS YH-502T。通过小角X射线散射、透射电镜和原子力显微镜表征了充油SEEP... 对具有代表性的多种SEEPS和SEBS进行了结构分析和相对分子质量检测,筛选出化学结构不同但苯乙烯含量相同且相对分子质量接近而具有可比性的SEEPS Kuraray-4055和SEBS YH-502T。通过小角X射线散射、透射电镜和原子力显微镜表征了充油SEEPS与SEBS体系的微观结构,显示SEEPS体系的相尺寸(49.1 nm)和相间距(47.9 nm)比SEBS体系的相尺寸(38.3 nm)和相间距(38.1 nm)大,前者具有更完整的微相分离;结合核磁共振氢谱的结果,发现这是由于SEEPS软段中氢化异戊二烯链段单元的存在使其链段柔顺性高于SEBS所致。根据Instron万能材料试验机和动态力学性能分析结果可知,相同条件下微相分离程度更高的SEEPS体系所具有的力学性能和储能模量均大于SEBS体系。研究结果表明,SEEPS/SEBS的分子结构是影响其充油体系微观结构、力学性能及动态力学性能的主要因素。 展开更多
关键词 苯乙烯-乙烯/乙烯/丙烯-苯乙烯三嵌段共聚物 苯乙烯-乙烯/丁烯-苯乙烯三嵌段共聚物 分子链结构 微相结构 力学性能 动态力学性能
下载PDF
Regulating the d band in WS_(2)@NC hierarchical nanospheres for efficient lithium polysulfide conversion in lithium-sulfur batteries 被引量:3
9
作者 Jintao Liu Shuhao Xiaoa +5 位作者 Le Chang Long Lai rui wu Yong Xiang Xingquan Liu Jun Song Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期343-352,共10页
The performance of lithium-sulfur batteries is deteriorated by the inferior conductivity of sulfur,the shuttle effect of lithium polysulfides(LiPSs),sluggish redox kinetics of polysulfide intermediates and serious vol... The performance of lithium-sulfur batteries is deteriorated by the inferior conductivity of sulfur,the shuttle effect of lithium polysulfides(LiPSs),sluggish redox kinetics of polysulfide intermediates and serious volumetric expansion of sulfur.To overcome these challenges,we report a versatile route to prepare multi-functional nanocomposites with tuable hierarchical structure via ammonium hydroxide(NH_(3)·H_(2) O)induced self-assembly.The versatility of the system has been demonstrated that the organization of the hierarchical structure can be regulated by adding different amounts of NH_(3)·H_(2) O,and WS_(2) and Co_(9)S_(8) with nitrogen-doped carbon coating(denoted as WS_(2)@NC and Co_(9)S_(8)@NC)can be prepared by adding different precursor salts.When the as-prepared materials are applied for Li-S batteries,the WS_(2)@NC composite exhibits a reversible capacity of 1107.4 mAh g^(-1) at 0.1 C after 500 cycles and even 728.9 mAh g^(-1) at2 C for 1000 cycles,which is significantly better than the Co_(9)S_(8) counterpart and other reported WS_(2) sulfur hosts.Experimentally,the advantageous performance of WS_(2) could be attributed to its higher surface area and total pore volume,giving rise to the easier access to electrolyte and better ability to buffer the volume change during the charge/discharge process.Theoretically,the density function theory(DFT)calculation reveals that the as-prepared WS_(2) has a higher binding energy towards LiPSs as well as a lower energy barrier for Li^(+)diffusion on the surface than Co_(9)S_(8).More significantly,the density of states(DOS)analysis further confirms that the superior performance is mainly ascribed to the more prominent shifting and the more charge compensation from d band of W than Co,which increase electronic concentration and give more hybridization of d-p orbitals in the Fermi level of the adsorbed Li2 S4 to accelerate the lithium polysulfide interfacial redox and conversion dynamics in WS_(2).By proposing this mechanism,this work sheds new light on the understanding of catalytic conversion of lithium polysulfides at the atomic level and the strategy to develop advanced cathode materials for high-performance lithium-sulfur batteries. 展开更多
关键词 Dband regulation Density of states DFT theoretical calculations Metal sulfides Lithium-sulfur batteries
下载PDF
C-C chemokine receptor type 2-overexpressing exosomes alleviated experimental post-stroke cognitive impairment by enhancing microglia/macrophage M2 polarization 被引量:6
10
作者 Huai-Chun Yang Min Zhang +5 位作者 rui wu Hai-Qing Zheng Li-Ying Zhang Jing Luo Li-Li Li Xi-Quan Hu 《World Journal of Stem Cells》 SCIE 2020年第2期152-167,共16页
BACKGROUND Human-derived mesenchymal stromal cells have been shown to improve cognitive function following experimental stroke.The activity of exosomes has been verified to be comparable to the therapeutic effects of ... BACKGROUND Human-derived mesenchymal stromal cells have been shown to improve cognitive function following experimental stroke.The activity of exosomes has been verified to be comparable to the therapeutic effects of mesenchymal stromal cells.However,the effects of exosomes derived from human umbilical cord mesenchymal stem cells(HUC-MSCs)(ExoCtrl)on post-stroke cognitive impairment(PSCI)have rarely been reported.Moreover,whether exosomes derived from C-C chemokine receptor type 2(CCR2)-overexpressing HUC-MSCs(ExoCCR2)can enhance the therapeutic effects on PSCI and the possible underlying mechanisms have not been studied.AIM To investigate the effects of ExoCtrl on PSCI and whether ExoCCR2 can enhance therapeutic effects on PSCI.METHODS Transmission electron microscopy,qNano®particles analyzer,and Western blotting were employed to determine the morphology and CCR2 expression of ExoCtrl or ExoCCR2.ELISA was used to study the binding capacity of exosomes to CC chemokine ligand 2(CCL2)in vivo.After the intravenous injection of ExoCtrl or ExoCCR2 into experimental rats,the effect of ExoCtrl and ExoCCR2 on PSCI was assessed by Morris water maze.Remyelination and oligodendrogenesis were analyzed by Western blotting and immunofluorescence microscopy.QRT-PCR and immunofluorescence microscopy were conducted to compare the microglia/macrophage polarization.The infiltration and activation of hematogenous macrophages were analyzed by Western blotting and transwell migration analysis.RESULTS CCR2-overexpressing HUC-MSCs loaded the CCR2 receptor into their exosomes.The morphology and diameter distribution between ExoCtrl and ExoCCR2 showed no significant difference.ExoCCR2 bound significantly to CCL2 but ExoCtrl showed little CCL2 binding.Although both ExoCCR2 and ExoCtrl showed beneficial effects on PSCI,oligodendrogenesis,remyelination,and microglia/macrophage polarization,ExoCCR2 exhibited a significantly superior beneficial effect.We also found that ExoCCR2 could suppress the CCL2-induced macrophage migration and activation in vivo and in vitro,compared with ExoCtrl treated group.CONCLUSION CCR2 over-expression enhanced the therapeutic effects of exosomes on the experimental PSCI by promoting M2 microglia/macrophage polarization,enhancing oligodendrogenesis and remyelination.These therapeutic effects are likely through suppressing the CCL2-induced hematogenous macrophage migration and activation.Key words:Cognitive impairment;Stroke;Exosomes;C-C chemokine receptor type 2;Microglia/macrophage polarization;Remyelination. 展开更多
关键词 Cognitive impairment Stroke EXOSOMES C-C chemokine receptor type 2 Microglia/macrophage polarization REMYELINATION
下载PDF
Effect of Supplemental Oregano Essential Oils in Diets on Production Performance and Relatively Intestinal Parameters of Laying Hens 被引量:4
11
作者 Xianjing He Dandan Hao +5 位作者 Chunhai Liu Xu Zhang Dandan Xu Xiaonan Xu Jianfa Wang rui wu 《American Journal of Molecular Biology》 2017年第1期73-85,共13页
This study was designed to investigate the effects of dietary oregano essential oils on 150 30-week-old Hy-Line Layers’ productive performance, egg quality characteristics, cecal microbiota, digestive enzyme activiti... This study was designed to investigate the effects of dietary oregano essential oils on 150 30-week-old Hy-Line Layers’ productive performance, egg quality characteristics, cecal microbiota, digestive enzyme activities, mucosa structure of the duodenum and jejunum and glucose and small peptides transporters expression in the duodenum and jejunum. All hens were allocated into one of five different groups: negative control (NC;basal diet only), antibiotics control (CS;basal diet plus 100 mg/kg of 10% colistin sulfate) and treatments I, II, and III (basal diet supplemented with 50, 100 and 150 mg/kg oregano essential oils, respectively). The results showed that the laying rate, average egg weight, feed conversion ratio and the activities of amylase and trypsin were significantly improved by a diet supplemented with 100 mg/kg oregano essential oils (P 0.05), significantly increased duodenum villus-height-to-crypt-depth ratios (P 0.05). 展开更多
关键词 LAYING HENS Oregano ESSENTIAL OILS INTESTINAL Morphology INTESTINAL Function
下载PDF
Secretion of nerve growth factor,brain-derived neurotrophic factor,and glial cell-line derived neurotrophic factor in co-culture of four cell types in cerebrospinal fluid-containing medium 被引量:1
12
作者 Sanjiang Feng Minghua Zhuang rui wu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第36期2907-2914,共8页
The present study co-cultured human embryonic olfactory ensheathJng cells, human Schwann cells, human amniotic epithelial cells and human vascular endothelial cells in complete culture medium- containing cerebrospinal... The present study co-cultured human embryonic olfactory ensheathJng cells, human Schwann cells, human amniotic epithelial cells and human vascular endothelial cells in complete culture medium- containing cerebrospinal fluid. Enzyme linked immunosorbent assay was used to detect nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor secretion in the supernatant of co-cultured cells. Results showed that the number of all cell types reached a peak at 7-10 days, and the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor peaked at 9 days. Levels of secreted nerve growth factor were four-fold higher than brain-derived neurotrophic factor, which was three-fold higher than glial cell line-derived neurotrophic factor. Increasing concentrations of cerebrospinal fluid (10%, 20% and 30%) in the growth medium caused a decrease of neurotrophic factor secretion Results indicated co-culture of human embryonic olfactory ensheathing cells, human Schwann cells human amniotic epithelial cells and human vascular endothelial cells improved the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor. The reduction of cerebrospinal fluid extravasation at the transplant site after spinal cord injury is beneficial for the survival and secretion of neurotrophic factors from transplanted cells. 展开更多
关键词 olfactory ensheathing cells Schwann cells amniotic epithelial cells vascular endothelial cells nerve growth factor brain-derived neurotrophic factor glial cell line-derived neurotrophic factor cerebrospinal fluid REGENERATION neural regeneration
下载PDF
Stress and deformation analysis of gob-side pre-backfill driving procedure of longwall mining:a case study 被引量:1
13
作者 rui wu Penghui Zhang +2 位作者 Pinnaduwa H.S.W.Kulatilake Hao Luo Qingyuan He 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第6期1351-1370,共20页
At present,non-pillar entry protection in longwall mining is mainly achieved through either the gob-side entry retaining(GER)procedure or the gob-side entry driving(GED)procedure.The GER procedure leads to difficultie... At present,non-pillar entry protection in longwall mining is mainly achieved through either the gob-side entry retaining(GER)procedure or the gob-side entry driving(GED)procedure.The GER procedure leads to difficulties in maintaining the roadway in mining both the previous and current panels.A narrow coal pillar about 5-7 m must be left in the GED procedure;therefore,it causes permanent loss of some coal.The gob-side pre-backfill driving(GPD)procedure effectively removes the wasting of coal resources that exists in the GED procedure and finds an alternative way to handle the roadway maintenance problem that exists in the GER procedure.The FLAC^(3D) software was used to numerically investigate the stress and deformation distributions and failure of the rock mass surrounding the previous and current panel roadways during each stage of the GPD procedure which requires"twice excavation and mining".The results show that the stress distribution is slightly asymmetric around the previous panel roadway after the"primary excavation".The stronger and stiffer backfill compared to the coal turned out to be the main bearing body of the previous panel roadway during the"primary mining".The highest vertical stresses of 32.6 and 23.1 MPa,compared to the in-situ stress of 10.5 MPa,appeared in the backfill wall and coal seam,respectively.After the"primary mining",the peak vertical stress under the coal seam at the floor level was slightly higher(18.1 MPa)than that under the backfill(17.8 MPa).After the"secondary excavation",the peak vertical stress under the coal seam at the floor level was slightly lower(18.7 MPa)than that under the backfill(19.8 MPa);the maximum floor heave and maximum roof sag of the current panel roadway were 252.9 and 322.1 mm,respectively.During the"secondary mining",the stress distribution in the rock mass surrounding the current panel roadway was mainly affected by the superposition of the front abutment pressure from the current panel and the side abutment pressure from the previous panel.The floor heave of the current panel roadway reached a maximum of 321.8 mm at 5 m ahead of the working face;the roof sag increased to 828.4 mm at the working face.The peak abutment pressure appeared alternately in the backfill and the coal seam during the whole procedure of"twice excavation and mining"of the GPD procedure.The backfill provided strong bearing capacity during all stages of the GPD procedure and exhibited reliable support for the roadway.The results provide scientific insight for engineering practice of the GPD procedure. 展开更多
关键词 Gob-side pre-backfill driving procedure Floor heave Roadway stability Stress distribution Abutment pressure
下载PDF
Monitoring the morphology evolution of LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)during high-temperature solid state synthesis via in situ SEM 被引量:1
14
作者 Liang Tang Xiaopeng Cheng +4 位作者 rui wu Tianci Cao Junxia Lu Yuefei Zhang Ze Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第3期9-15,I0001,共8页
The particle morphology determined by the sintering process is the director factor affecting the electrochemical performance of Ni-rich NMC cathode materials.To prepare the ideal NMC particles,it is of great significa... The particle morphology determined by the sintering process is the director factor affecting the electrochemical performance of Ni-rich NMC cathode materials.To prepare the ideal NMC particles,it is of great significance to understand the morphological changes during sintering process.In this work,the morphology evolution of LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811)synthesis at temperature ranging from 300–1080℃were observed by in situ SEM.The uniform mixture of spherical Ni_(0.8)Mn_(0.1)Co_(0.1)(OH)_(2)precursor and lithium sources(LiOH)was employed by high temperature solid-state process inside the SEM,which enables us to observe morphology changes in real time.The results show that synthetic reaction of LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)usually includes three processes:the raw materials’dehydration,oxidation,and combination,accompanied by a significant reduction in particle size,which is important reference to control the synthesis temperature.As heating temperature rise,the morphology of mixture also changed from flake to brick-shaped.However,Ni nanoparticle formation is apparent at higher temperature~1000℃,suggesting a structural transformation from a layered to a rock-salt-like structure.Combining the in-situ observed changes in size and morphology,and with the premise of ensuring the morphology change from flakes to bricks,reducing the sintering temperature as much as possible to prevent excessive reduction in particle size and layered to a rock-salt structure transformation is recommended for prepare ideal NMC particles. 展开更多
关键词 Lithium-ion battery NMC cathode In situ SEM High temperature imaging Particle morphology
下载PDF
Thermodynamic property of ternary compound MgCaSi: A study from ab initio Debye-Grüneisen model 被引量:1
15
作者 rui wu Ya-Ping Wang +2 位作者 Lin Shao Wei Wang Bi-Yu Tang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第12期315-322,共8页
The thermodynamic properties of Mg Ca Si and its mother phase Ca2 Si are comparatively investigated from ab initio calculations and quasi-harmonic Debye-Grüneisen model. At 0 K, Mg Ca Si is more thermodynamically... The thermodynamic properties of Mg Ca Si and its mother phase Ca2 Si are comparatively investigated from ab initio calculations and quasi-harmonic Debye-Grüneisen model. At 0 K, Mg Ca Si is more thermodynamically stable. Under high temperature, the advantage of higher thermodynamically stability of Mg Ca Si is reduced, originating from the less negative entropy contribution because the thermodynamic entropy of Mg Ca Si increases more slowly with temperature and the entropy values are slightly smaller.With increasing temperature, the anti-softening ability for Mg Ca Si is slightly smaller due to the slightly faster decrease trend of bulk modulus than that of Ca2 Si, although the bulk modulus of Mg Ca Si is higher in the whole temperature range considered. The thermal expansion behaviors of both Mg Ca Si and Ca_(2)Si exhibit similar increase trend, although thermal expansion coefficient of MgCaSi is slightly lower and the increases is slightly slower at lower temperature. The isochoric heat capacity CVand isobaric heat capacity CPof MgCaSi and Ca_(2)Si rise nonlinearly with temperature, and both CVare close to the Dulong–Petit limit at high temperature due to the negligibly small electronic contribution. The Debye temperature of both phases decrease with increasing temperature, and the downtrend for Mg Ca Si is slightly faster.However, MgCaSi possess slightly higher Debye temperature, implying the stronger chemical bonds and higher thermal conductivity than the mother phase Ca_(2)Si. The Grüneisen parameter of MgCaSi and Ca_(2)Si increase slightly with temperature, the values of MgCaSi are slightly larger. The investigation of electronic structures shows that with substitution of partial Ca by Mg in Ca_(2)Si, the stronger MgASi,MgACa and SiASi covalent bonds are formed, and plays a very significant role for the structural stability and mechanical properties. 展开更多
关键词 MgCaSi alloys Density functional theory Thermodynamic properties Structural stabilities Quasi-harmonic Debye-Grüneisen model
下载PDF
Moirésuperlattice modulations in single-unit-cell FeTe films grown on NbSe_(2)single crystals 被引量:1
16
作者 邓翰宾 李渊 +15 位作者 冯子力 关剑宇 于鑫 黄雄 刘睿哲 朱长江 刘立民 孙英开 彭锡亮 李帅帅 杜鑫 王铮 武睿 殷嘉鑫 石友国 毛寒青 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第12期131-135,共5页
Interface can be a fertile ground for exotic quantum states,including topological superconductivity,Majorana mode,fractal quantum Hall effect,unconventional superconductivity,Mott insulator,etc.Here we grow single-uni... Interface can be a fertile ground for exotic quantum states,including topological superconductivity,Majorana mode,fractal quantum Hall effect,unconventional superconductivity,Mott insulator,etc.Here we grow single-unit-cell(1UC)FeTe film on NbSe_(2)single crystal by molecular beam epitaxy(MBE)and investigate the film in-situ with a home-made cryogenic scanning tunneling microscopy(STM)and non-contact atomic force microscopy(AFM)combined system.We find different stripe-like superlattice modulations on grown FeTe film with different misorientation angles with respect to NbSe_(2)substrate.We show that these stripe-like superlattice modulations can be understood as moirépattern forming between FeTe film and NbSe_(2)substrate.Our results indicate that the interface between Fe Te and NbSe2 is atomically sharp.By STM-AFM combined measurement,we suggest that the moirésuperlattice modulations have an electronic origin when the misorientation angle is relatively small(≤3°)and have structural relaxation when the misorientation angle is relatively large(≥10°). 展开更多
关键词 scanning tunneling microscopy(STM) atomic force microscopy(AFM) FeTe film moirésuperlattice MISORIENTATION
下载PDF
Research progress in the treatment of diabetic kidney disease with Chinese medicine enema 被引量:2
17
作者 rui wu Jiaqi Chen +1 位作者 Zimengwei Ye Zhufeng Wang 《Journal of Traditional Chinese Medical Sciences》 2021年第3期205-215,共11页
Chinese medicine enema is an effective guiding method to treat diabetic kidney disease,a common chronic complication of diabetes,by regulating the function of the intestines to increase clearing and lower turbidity.We... Chinese medicine enema is an effective guiding method to treat diabetic kidney disease,a common chronic complication of diabetes,by regulating the function of the intestines to increase clearing and lower turbidity.We reviewed the treatment of diabetic kidney disease(DKD)with traditional Chinese medicine enemas and found that commonly used traditional Chinese medicines included Rhei Radix Et Rhizoma(Rheum palmatum L.),Ostrea concha(Ostrea gigas Thunberg),Taraxaci Herba(Taraxacum mongolicum Hand.-Mazz.),Astmgali Radix(Astragalus membranaceus Bge.var.mongholicus(Bge.)Hsiao),Salviae Miltiorrhizae Radix Et Rhizoma(Salvia miltiorrhiza Bge.),and Aconiti Lateralis Radix Praeparata(Aconitum carmichaelii Debx).The mechanism of the adjuvant therapeutic effect on DKD may relate to regulating intestinal flora,inhibiting inflammation and oxidative stress and protecting against kidney injury. 展开更多
关键词 Chinese medicine ENEMA Diabetic kidney disease
下载PDF
Room-temperature electric control of exchange bias effect in CoO1-δ/Co films using Pb(Mg1/3Nb2/3)0.7Ti0.3O3 (110) substrates 被引量:1
18
作者 闻馨 吴锐 +4 位作者 杨文云 王常生 刘顺荃 韩景智 杨金波 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第9期564-568,共5页
Significant electric control of exchange bias effect in a simple CoO1-δ/Co system, grown on piezoelectric Pb(Mg1/3Nb2/3)0.7Ti0.3O3 (110) (PMN-PT) substrates, is achieved at room temperature. Obvious changes in both t... Significant electric control of exchange bias effect in a simple CoO1-δ/Co system, grown on piezoelectric Pb(Mg1/3Nb2/3)0.7Ti0.3O3 (110) (PMN-PT) substrates, is achieved at room temperature. Obvious changes in both the coercivity field (HC) and the exchange bias field (HE), of 31% and 5%, respectively, have been observed when the electric field is applied to the substrate. While the change of coercivity is related to the enhanced uniaxial anisotropy in the ferromagnetic layer, the change of the exchange bias field can only originate from the spin reorientation in the antiferromagnetic CoO1-δ layer caused by the strain-induced magnetoelastic effect. A large HE/HC > 2, and HE~ 110 Oe at room temperature, as well as the low-energy fabrication of this system, make it a practical system for spintronic device applications. 展开更多
关键词 electric control exchange bias PMN-PT magnetic anisotropy
下载PDF
Molecular Weight and Distribution of Cellulose and Cellulose Microspheres 被引量:1
19
作者 Zefen WANG Kelin HUANG +4 位作者 Ben WANG rui wu Jing TAO Xiaoyu PENG Dankui LIAO 《Agricultural Biotechnology》 CAS 2012年第1期44-46,共3页
[ Objective ] This study aimed to provide basic data for studying the relationship between structure and property of cellulose microspheres by measuring molecular weight of cellulose and cellulose microspheres with vi... [ Objective ] This study aimed to provide basic data for studying the relationship between structure and property of cellulose microspheres by measuring molecular weight of cellulose and cellulose microspheres with viscosity method and gel permeation chromatography (GPC) method. [ Method] In viscosity method, cadmium ethylenediamine was used as the solvent, intrinsic viscosity η of the solution was determined at 25 ℃ by using a Ubbelohde viscometer, to calculate the molecular weight of cellulose; in GPC method, 8% LiC1 / N, N-dimethylacetamide (LiC1/DMAc) was used as the solvent and 0.5% LiC1/DMAc was used as the mobile phase to determine the relative molecular weight and distribution of cellulose and cellulose microspheres. In addition, the determination results were analyzed to compare these two methods. [ Result ] Viscosity-average molecular weight Mr/ of cellulose and cellulose microspheres determined with viscosity method were 224,532 and 16,686, respectively; weight-average molecular weight Mw of cellulose and cellulose microspheres determined with GPC method were 284,196 and 22,345, respectively. [ Conclusion] The determination results of (;PC method are relatively close to the actual value and could truly reflect the characteristics of molecular weialat distribution of eellulose and cellulose mierosr, heres. 展开更多
关键词 Cellulose microspheres Viscosity method GPC method Molecular weight Molecular weight distribution
下载PDF
Relationship between obstructive sleep apnea hypopnea syndrome and cardiovascular disorders in adult snorers 被引量:1
20
作者 rui wu Xilong Zhang +1 位作者 Ling Hu Enzhi Jia 《Journal of Nanjing Medical University》 2009年第1期59-63,共5页
Objective:To investigate the relationship between sleep apnea hypopnea syndrome(OSAHS) and some cardiovascular disorders in adult habitual snorers as well as the effectiveness of nasal continuous positive airway pr... Objective:To investigate the relationship between sleep apnea hypopnea syndrome(OSAHS) and some cardiovascular disorders in adult habitual snorers as well as the effectiveness of nasal continuous positive airway pressure(NCPAP) on those with OSAHS. Methods: With the use of polysomnography, 262 adult habitual snorers were examined and divided into the OSAHS group and the Non-OSAHS group (control). Using ambulatory electrocardiogram and blood pressure measurement, daily nocturnal rhythm of blood pressure, hypertension, heart rate variability, some arrythmias and angina pectoris of coronary heart disease were monitored and compared between the two groups, before and after 14 days of treatment with NCPAP in the OSAHS group. Results.This study indicated a higher incidence (39.6%) of OSAHS in adult snorers and demonstrated that there was a significantly higher incidence of hypertension, disappearance of the daily nocturnal rhythm of blood pressure, poor effectiveness of nitrate on angina pectoris of coronary heart disease, decreased heart rate variability during sleep, increased arrythmias and lower SpO2 levels in the OSAHS group than in the Non-OSAHS group. After NCPAP treatment during sleep, snoring control, significantly higher SpO2 and lower apnea hypopnea indices were achieved in the OSAHS group; heart rate variability and daily nocturnal rhythm of blood pressure returned to normal levels. Conclusion:The results of this research suggested that there was a close relationship between the development of OSAHS and some cardiovascular disorders. Furthermore, NCPAP treatment was effective not only on OSAHS but also on coexisting cardiovascular disorders. 展开更多
关键词 Obstructive sleep apnea hypopnea syndrome cardiovascular disorder SNORING
下载PDF
上一页 1 2 4 下一页 到第
使用帮助 返回顶部