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The auxin transporter OsAUX1 regulates tillering in rice(Oryza sativa)
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作者 Luqi Jia Yongdong Dai +7 位作者 Ziwei Peng Zhibo Cui xuefei zhang Yangyang Li Weijiang Tian Guanghua He Yun Li Xianchun Sang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1454-1467,共14页
Tillering is an important agronomic trait of rice(Oryza sativa)that affects the number of effective panicles,thereby affecting yields.The phytohormone auxin plays a key role in tillering.Here we identified the high ti... Tillering is an important agronomic trait of rice(Oryza sativa)that affects the number of effective panicles,thereby affecting yields.The phytohormone auxin plays a key role in tillering.Here we identified the high tillering and semi-dwarf 1(htsd1)mutant with auxin-deficiency root characteristics,such as shortened lateral roots,reduced lateral root density,and enlarged root angles.htsd1 showed reduced sensitivity to auxin,but the external application of indole-3-acetic acid(IAA)inhibited its tillering.We identified the mutated gene in htsd1 as AUXIN1(OsAUX1,LOC_Os01g63770),which encodes an auxin influx transporter.The promoter sequence of OsAUX1 contains many SQUAMOSA PROMOTER BINDING PROTEIN-LIKE(SPL)binding sites,and we demonstrated that SPL7 binds to the OsAUX1 promoter.TEOSINTE BRANCHED1(OsTB1),a key gene that negatively regulates tillering,was significantly downregulated in htsd1.Tillering was enhanced in the OsTB1 knockout mutant,and the external application of IAA inhibited tiller elongation in this mutant.Overexpressing OsTB1 restored the multi-tiller phenotype of htsd1.These results suggest that SPL7 directly binds to the OsAUX1 promoter and regulates tillering in rice by altering OsTB1 expression to modulate auxin signaling. 展开更多
关键词 rice(Oryza sativa L.) TILLERING indole-3-acetic acid(IAA) OsAUX1 OsTB1
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Experimental investigation into the salinity effect on the physicomechanical properties of carbonate saline soil
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作者 Jiejie Shen Qing Wang +3 位作者 Yating Chen xuefei zhang Yan Han Yaowu Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1883-1895,共13页
For engineering structures with saline soil as a filling material,such as channel slope,road subgrade,etc.,the rich soluble salt in the soil is an important potential factor affecting their safety performance.This stu... For engineering structures with saline soil as a filling material,such as channel slope,road subgrade,etc.,the rich soluble salt in the soil is an important potential factor affecting their safety performance.This study examines the Atterberg limits,shear strength,and compressibility of carbonate saline soil samples with different NaHCO3 contents in Northeast China.The mechanism underlying the influence of salt content on soil macroscopic properties was investigated based on a volumetric flask test,a mercury intrusion porosimetry(MIP)test,and a scanning electron microscopic(SEM)test.The results demonstrated that when NaHCO3 contents were lower than the threshold value of 1.5%,the bound water film adsorbed on the surface of clay particles thickened continuously,and correspondingly,the Atterberg limits and plasticity index increased rapidly as the increase of sodium ion content.Meanwhile,the bonding force between particles was weakened,the dispersion of large aggregates was enhanced,and the soil structure became looser.Macroscopically,the compressibility increased and the shear strength(mainly cohesion)decreased by 28.64%.However,when the NaHCO3 content exceeded the threshold value of 1.5%,the salt gradually approached solubility and filled the pores between particles in the form of crystals,resulting in a decrease in soil porosity.The cementation effect generated by salt crystals increased the bonding force between soil particles,leading to a decrease in plasticity index and an improvement in soil mechanical properties.Moreover,this work provides valuable suggestions and theoretical guidance for the scientific utilization of carbonate saline soil in backfill engineering projects. 展开更多
关键词 Carbonate saline soil Salt content Physicomechanical properties Bound water MICROSTRUCTURE
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Unravelling the role of boron dopant in borocarbonitirde catalytic dehydrogenation reaction
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作者 xuefei zhang Yanbing Lu +2 位作者 Yingyi Han Runping Feng Zailai Xie 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期137-143,I0006,共8页
Borocarbonitride(BCN) materials are newly developed metal-free catalytic materials exhibiting high selectivity in oxidative dehydrogenation(ODH) of alkanes. However, the in-depth understandings on the role of boron(B)... Borocarbonitride(BCN) materials are newly developed metal-free catalytic materials exhibiting high selectivity in oxidative dehydrogenation(ODH) of alkanes. However, the in-depth understandings on the role of boron(B) dopants and the intrinsic activities of –C=O and –B–OH still remain unknown.Herein, we report a series of BCN materials with regulable B content and surface oxygen functional groups via self-assembly and pyrolysis of guanine and boric acid. We found that the B/C ratio is the key parameter to determine the activity of ODH and product distribution. Among them, the high ethylbenzene conversion(~57%) and styrene selectivity(~83%) are achieved in ODH for B_(1)CN. The styrene selectivity can be improved by increasing of B/C ratio and this value reaches near 100% for B_5CN.Structural characterizations and kinetic measurements indicate that –C=O and –B–OH dual sites on BCN are real active sites of ODH reaction. The intrinsic activity of –C=O(5.556 × 10^(-4)s^(-1)) is found to be 23.7 times higher than –B–OH(0.234 × 10^(-4)s^(-1)) site. More importantly, we reveal that the deep oxidation to undesirable CO_(2) occurs on –C=O rather than –B–OH site, and B dopant in BCN materials can reduce the nucleophilicity of –C=O site to eliminate the CO_(2) emission. Overall, the present work provides a new insight on the structure–function relationship of the BCN catalytic systems. 展开更多
关键词 Borocarbonitride Oxidative dehydrogenation Intrinsic activity CO_(2)selectivity
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血清细胞角蛋白19片段与胸腺肿瘤临床病理特征和预后的相关性研究 被引量:7
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作者 章雪飞 吉春宇 +1 位作者 谷志涛 方文涛 《中国肺癌杂志》 CAS CSCD 北大核心 2018年第7期519-525,共7页
背景与目的胸腺肿瘤中尚无肿瘤标志物的应用,本研究旨在评估血清细胞角蛋白19片段(cytokeratin 19 fragment,Cyfra 21-1)与胸腺肿瘤临床病理特征和预后的相关性。方法回顾性分析上海市胸科医院2012年11月-2016年9月收治的159例胸腺肿瘤... 背景与目的胸腺肿瘤中尚无肿瘤标志物的应用,本研究旨在评估血清细胞角蛋白19片段(cytokeratin 19 fragment,Cyfra 21-1)与胸腺肿瘤临床病理特征和预后的相关性。方法回顾性分析上海市胸科医院2012年11月-2016年9月收治的159例胸腺肿瘤病例的临床资料。比较术前血清Cyfra 21-1水平在不同分期及组织学类型间的差异,研究术前及术后血清Cyfra 21-1水平与复发的关系。结果在局部晚期(T4期)(P<0.001)、胸腺癌(P<0.001)患者中,术前血清Cyfra 21-1水平显著升高,且当术前Cyfra 21-1≥1.66 ng/m L时,其对术后复发有提示意义。分析患者随访的血清Cyfra 21-1,将2.66 ng/m L作为cut-off值时,提示胸腺肿瘤复发的敏感度为0.667,特异度为0.925,阳性预测值为0.462,阴性预测值为0.966。结论术前患者血清Cyfra 21-1水平较高,有助于提示肿瘤分期较晚、肿瘤恶性程度较高,或可提示术后复发的风险升高。在随访时结合血清Cyfra 21-1检测,将可能有助于提高复发患者的检出率,改善预后。 展开更多
关键词 胸腺肿瘤 细胞角蛋白19片段 肿瘤分期 组织学类型 预后
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O,H,and Sr isotope evidence for origin and mixing processes of the Gudui geothermal system,Himalayas,China 被引量:5
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作者 Chenguang Wang Mianping Zheng +4 位作者 xuefei zhang Enyuan Xing Jiangyi zhang Jianhong Ren Yuan Ling 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第4期1175-1187,共13页
Tho Gudui geothermal field records the highest temperature at equivalent borehole depths among the lainland hydrothermal systems in China's Mainland.Located about 150 km southeast of Lhasa City,the capital of Tibe... Tho Gudui geothermal field records the highest temperature at equivalent borehole depths among the lainland hydrothermal systems in China's Mainland.Located about 150 km southeast of Lhasa City,the capital of Tibet,the Gudui geothermal field belongs to the Sangri-Cuona rift belt,also known as the Sangri-Cuona geothermal belt,and is representative of the non-volcanic geothermal systems in the Himalayas.In this study,oxygen-18 and deuterium isotope compositions as well as 87Sr/86Sr ratios of water samples collected from the Gudui geothermal field were characterized to understand the origin and mixing processes of the geothermal fluids at Gudui.Hydrogen and oxygen isotope plots show both,deep and shallow reservoirs in the Gudui geothermal field.Deep geothermal fluids are the mixing product of magmatic and infiltrating snow-melt water.Calculations show that the magma fluid component of the deep geothermal fluids account for about 21.10%-24.04%;magma fluids lay also be a contributing source of lithium.The linear relationship of the 87Sr/86Sr isotopic ratio versus the 1/Sr plot indicates that shallow geothermal fluids form from the mixing of deep geothermal fluids with cold groundwater.Using a binary mixing model with deep geothermal fluid and cold groundwater as two end-members,the nixing ratios of the latter in most surface hot springs samples were calculated to be between 5% and 10%.Combined with basic geological characteristics,hydrogen and oxygen isotope characteristics,strontium concentration,87Sr/(86)Sr ratios,and the binary mixing model,we infer the 6 th-Class Reservoirs Evolution Conceptual Model(6-CRECM) for the Gudui geothermal system.This model represents an idealized summary of the characteristics of the Gudui geothermal field based on our comprehensive understanding of the origin and mixing processes of the geothermal fluid in Gudui.This study may aid in identifying the geothermal and geochemical origin of the Gudui high-temperature hydrothermal systems in remote Tibet of China,whose potential for geothermal development and utilization is enormous and untapped. 展开更多
关键词 Geothermal fluid Oxygen-18 and deuterium isotope 87Sr/86Sr ratio Origin and mixing Gudui HIMALAYAS
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Two-Timescale Online Learning of Joint User Association and Resource Scheduling in Dynamic Mobile Edge Computing 被引量:2
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作者 Jian zhang Qimei Cui +2 位作者 xuefei zhang Xueqing Huang Xiaofeng Tao 《China Communications》 SCIE CSCD 2021年第8期316-331,共16页
For the mobile edge computing network consisting of multiple base stations and resourceconstrained user devices,network cost in terms of energy and delay will incur during task offloading from the user to the edge ser... For the mobile edge computing network consisting of multiple base stations and resourceconstrained user devices,network cost in terms of energy and delay will incur during task offloading from the user to the edge server.With the limitations imposed on transmission capacity,computing resource,and connection capacity,the per-slot online learning algorithm is first proposed to minimize the time-averaged network cost.In particular,by leveraging the theories of stochastic gradient descent and minimum cost maximum flow,the user association is jointly optimized with resource scheduling in each time slot.The theoretical analysis proves that the proposed approach can achieve asymptotic optimality without any prior knowledge of the network environment.Moreover,to alleviate the high network overhead incurred during user handover and task migration,a two-timescale optimization approach is proposed to avoid frequent changes in user association.With user association executed on a large timescale and the resource scheduling decided on the single time slot,the asymptotic optimality is preserved.Simulation results verify the effectiveness of the proposed online learning algorithms. 展开更多
关键词 user association resource scheduling stochastic gradient descent two-timescale optimization mobile edge computing
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Apigenin as a promising myocyte protectant against damage and degradation
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作者 XIAO HUANG ZHIHAI YU +3 位作者 LIJUAN NING YU LEI xuefei zhang ZHUYING WANG 《BIOCELL》 SCIE 2022年第2期383-388,共6页
Myocytes power the movement of all organs in the body.Damage to and degradation of myocytes causes hypokinesia and muscle-related degenerative diseases.Apigenin,a kind of flavone,is being used to treat many disorders.... Myocytes power the movement of all organs in the body.Damage to and degradation of myocytes causes hypokinesia and muscle-related degenerative diseases.Apigenin,a kind of flavone,is being used to treat many disorders.It exerts a host of different pharmacological activities,such as anti-inflammatory,anti-mutagenic,cardioprotective,and antioxidant effects.Accordingly,apigenin is considered a promising candidate for myocyte protection.In this review,we introduced the characteristics of apigenin.The means of apigenin protection of myocytes as well as the mechanism were summarized and discussed.The protective effects can be classified into proliferation-promoting,anti-inflammatory,atrophy-preventing,metabolism-increasing,and antioxidative effects.Additionally,we provided some outlook on the valuable applications of apigenin in sports medicine,which eagerly require further fundamental research. 展开更多
关键词 APIGENIN MYOCYTE Protectant Pharmacological activity
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Basic properties of saline soil in Da'an, western Jilin, China
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作者 Xin Zhou Qing Wang +2 位作者 xuefei zhang TianWen Yu XuDong zhang 《Research in Cold and Arid Regions》 CSCD 2015年第5期568-572,共5页
This paper studied the basic properties of saline soil at different depths of a sampling site in Da'an, China, through field reconnaissance and laboratory analysis. A series of experiments which comprised the analyse... This paper studied the basic properties of saline soil at different depths of a sampling site in Da'an, China, through field reconnaissance and laboratory analysis. A series of experiments which comprised the analyses of grain size distribution, mineral composition, soil physical properties, soluble salt concent, pH, organic content and cation exchange capacity were conducted. Through these experiments, the distribution rule of each property and their causes are discussed. These results could provide a fundamental base for the study of moisture migration. 展开更多
关键词 saline soil basic properties distribution rule moisture migration
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Research and Experiment on Performance Stability of Facility Green-house Environmental Monitoring System
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作者 Hao WANG xuefei zhang +2 位作者 Xiang SUN Haibo SUN Yixin XU 《Asian Agricultural Research》 2018年第8期81-84,共4页
At present,the safety and stability of most facility greenhouse environment monitoring systems are seldom considered. In order to improve the stability of data transmission in environment and prevent the system failur... At present,the safety and stability of most facility greenhouse environment monitoring systems are seldom considered. In order to improve the stability of data transmission in environment and prevent the system failure caused by the fault of coordinator,a mechanism based on Zigbee coordinator to improve the stability of the whole system is proposed to ensure the security of wireless data transmission. Finally,the system is tested,and the results show that the system can effectively ensure the fault-free transmission of collected environmental data. 展开更多
关键词 温室环境 监测系统 安全性 农业
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6G无线覆盖扩展技术
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作者 许晓东 韩书君 +21 位作者 赵芸 王静贤 何睿斯 王德胜 侯延昭 费泽松 张雪菲 侯利明 郭婧 艾渤 牛勇 熊轲 王方刚 章嘉懿 沈霞 杜滢 刘玲 杜清河 王碧舳 孙梦颖 张静璇 谭力 《中国科学:信息科学》 CSCD 北大核心 2024年第5期1144-1176,共33页
根据国际电信联盟关于IMT-2030愿景,第6代移动通信系统(the 6th generation mobile networks,6G)的覆盖服务需求将从单场景覆盖向多场景覆盖扩展,6G基础设施的部署也将逐步从2D覆盖向3D覆盖扩展、从局部覆盖向全球覆盖扩展、从中低频段... 根据国际电信联盟关于IMT-2030愿景,第6代移动通信系统(the 6th generation mobile networks,6G)的覆盖服务需求将从单场景覆盖向多场景覆盖扩展,6G基础设施的部署也将逐步从2D覆盖向3D覆盖扩展、从局部覆盖向全球覆盖扩展、从中低频段融合使用向更高频段按需开启.上述需求使得6G在提升容量的同时,需要进一步考虑无线覆盖扩展需求.本文针对如何在6G网络结构时空尺度跨度大、全场景业务需求差异大、超密集覆盖能耗大等关键挑战下实现容量和能效约束下的覆盖能力扩展这一重大科学问题,首先提出了面向6G无线覆盖扩展的智能柔性组网架构;其次研究了面向6G无线覆盖扩展的关键技术,包括面向6G广域覆盖的多维立体空天地覆盖扩展技术、面向深度覆盖的超密集异构覆盖扩展技术和面向6G平滑度覆盖的超高速移动覆盖扩展技术;接着分析了基于语义通信的覆盖扩展技术;最后给出了6G全场景无线覆盖扩展仿真验证,通过定义6G无线覆盖扩展技术指标体系,进行了典型场景的覆盖性能仿真验证. 展开更多
关键词 6G 无线覆盖扩展 组网架构 关键技术 指标体系
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Guanine-derived F,N co-doped carbon-shell encapsulated iron carbide nanoparticles for enhanced CO_(2)electroreduction activity
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作者 Shuo Chen Lishun Pei +2 位作者 Ying Peng xuefei zhang Zailai Xie 《Nano Research》 SCIE EI CSCD 2024年第6期4744-4752,共9页
The development of highly selective,cost-effective,and energy-efficient electrocatalysts is critical for carbon dioxide reduction reaction(CO_(2)RR)to produce high-value products.Herein,we propose a facile strategy to... The development of highly selective,cost-effective,and energy-efficient electrocatalysts is critical for carbon dioxide reduction reaction(CO_(2)RR)to produce high-value products.Herein,we propose a facile strategy to obtain F,N co-doped carbon-coated iron carbide(Fe3C)nanoparticles by using biomolecule guanine and hexadecafluorophthalocyanine iron as raw materials.Remarkably,this method involves only one-step pyrolysis and does not require any guiding agent or sacrificial template.Benefiting from the advantageous surface microenvironment adjustments achieved through graphitic N(GN)and F co-doping,Fe3C@NF-G-1000 demonstrates exceptional efficacy in the electroreduction of CO_(2)to carbon monoxide(CO)with an impressive Faradic efficiency(FEco)up to 98%at the potential of−0.55 V(vs.reversible hydrogen electrode(RHE)).Furthermore,it delivers a remarkable current density of up to−43 mA·cm^(−2)and exhibits virtually no current attenuation over a span of 20 h within the flow cell.Insights from density functional theory(DFT)calculations reveal that the composite structure of GN and F co-doped graphitic layer and Fe3C exhibits different electron density distributions from that of iron carbide nanoparticles.This is attributed to the synergistic effect of the composite structure leading to the enrichment of electrons in the graphite layer on the surface,which contributes to the stability of the key reaction intermediate*COOH,thus,resulting in an enhanced catalytic activity and efficiency.Overall,this work introduces a new and promising approach to the design of green and low-cost carbon-coated metal materials for CO_(2)reduction reactions. 展开更多
关键词 GUANINE F N co-doped carbon dioxide reduction reaction(CO_(2)RR) Fe-based catalyst
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Lithium extraction from salt lakes with different hydrochemical types in the Tibet Plateau 被引量:3
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作者 Tao Ding Mianping Zheng +3 位作者 Suping Peng Yuhan Lin xuefei zhang Mingming Li 《Geoscience Frontiers》 SCIE CAS CSCD 2023年第1期230-246,共17页
The demand for lithium resources is increasing sharply with the rapid development of electric vehicles.It is of great economic significance to expand the geological resources of lithium and improve the utilization rat... The demand for lithium resources is increasing sharply with the rapid development of electric vehicles.It is of great economic significance to expand the geological resources of lithium and improve the utilization rate of lithium-containing salt lakes.In this paper,the hydrochemical types of the lithium-containing salt lakes in the Tibet Plateau were classified according to a large amount of hydrochemical data obtained from a recent investigation on the Tibet Plateau.In addition,the lithium extraction methods used in the salt lakes within each hydrochemical type area were analyzed and summarized,which provided a reference for the selection of lithium extraction processes in the same hydrochemical type of lithium-containing salt lakes in the future.The binding energies of Li(l)and anions in salt lakes with different hydrochemical types were calculated by density functional theory,which provides the theoretical basis for selecting the best lithium extraction technology in different salt lakes.We emphasize that the process with the combined characteristics of high efficiency,economy and environmental protection should be selected according to the hydrochemical type of different salt lakes.In the future,different salt lakes should focus on direct lithium extraction technology from the original brine. 展开更多
关键词 Tibet Plateau Lithium-containing salt lake Hydrochemical type Lithium extraction process
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Kinematic inventory of rock glaciers in the Nyainqentanglha Range using the MT-InSAR method
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作者 xuefei zhang Min Feng +5 位作者 Jinhao Xu Dezhao Yan Jing Wang Xiaoqing Zhou Tao Li Xiang zhang 《International Journal of Digital Earth》 SCIE EI 2023年第1期3923-3948,共26页
Rock glaciers are typical periglacial landforms with tongue or lobate morphological shapes and characterized by the distinct front,lateral margins,and often by ridge-and-furrow surface topography textures as well as k... Rock glaciers are typical periglacial landforms with tongue or lobate morphological shapes and characterized by the distinct front,lateral margins,and often by ridge-and-furrow surface topography textures as well as kinematic characteristics,widely distributed in alpine environments.Multitemporal Synthetic aperture radar interferometry(MT-InSAR),is a remote sensing technique with demonstrated effectiveness for detecting landform kinematics.However,its application to rock glaciers is challenged by temporal decorrelation and atmospheric phase noises due to complex topography and snow cover.We designed a quadtree segmentation and parallel computing-based MT-InSAR method to improve the quality and efficiency of deformation measurement of rock glaciers.We applied the method to a rock glacier inventory of the Nyainqentanglha Range,China,derived from high-resolution Gaofen-2 images,to quantify the activity rate of each rock glacier.Results showed that 32.1%(6,389)of the identified rock glaciers exhibited slope-parallel deformation rates exceeding 100 mm/y.The activities of the rock glaciers exhibited strong correlations with their distance to glaciers,precipitation,freeze-thaw magnitude,and permafrost occurrence probability.The results demonstrate the effectiveness of the developed segmentation-parallel MT-InSAR method for monitoring rock glacier deformation over a large region. 展开更多
关键词 Rock glacier MT-InSAR quadtree segmentation Nyaingentanglha KINEMATICS
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Voltage Profile Optimization of Active Distribution Networks Considering Dispatchable Capacity of 5G Base Station Backup Batteries
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作者 Yiyao Zhou Qianggang Wang +5 位作者 Yao Zou Yuan Chi Niancheng Zhou xuefei zhang Chen Li Qinqin Xia 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2023年第6期1842-1856,共15页
The penetration of distributed energy resources(DERs) and energy-intensive resources is gradually increasing in active distribution networks(ADNs), which leads to frequent and severe voltage violation problems. As a d... The penetration of distributed energy resources(DERs) and energy-intensive resources is gradually increasing in active distribution networks(ADNs), which leads to frequent and severe voltage violation problems. As a densely distributed flexible resource in the future distribution network, 5G base station(BS) backup battery is used to regulate the voltage profile of ADN in this paper. First, the dispatchable potential of 5G BS backup batteries is analyzed. Considering the spatial-temporal characteristics of electric load for 5G BS, the dispatchable capacity of backup batteries at different time intervals is evaluated based on historical heat map data. Then, a voltage profile optimization model for ADN is established, consisting of 5G BS backup batteries and other voltage regulation resources. In this model, the charging/discharging behavior of backup batteries is based on its evaluation result of dispatchable capacity. Finally, the range of charging/discharging cost coefficients of 5G BS that benefits ADN and 5G operators are analyzed respectively. Further, an incentive policy for 5G operators is proposed. Under this policy, the charging/discharging cost coefficients of 5G BS can achieve a win-win situation for ADN and 5G operators. As an emerging flexible resource in ADN, the effectiveness and economy of 5G BS backup batteries participating in voltage profile optimization are verified in a test distribution network. 展开更多
关键词 Voltage profile optimization 5G base station(BS)backup battery active distribution network(ADN) flexible resource voltage violation
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城市污泥与稻壳水热炭混合燃烧特性与动力学 被引量:6
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作者 叶聪 邢献军 +2 位作者 张学飞 陈涛 张佳佳 《过程工程学报》 CAS CSCD 北大核心 2020年第3期362-370,共9页
采用热重分析法研究城市污泥、稻壳水热炭及两者不同掺混比的燃烧特性与反应动力学。对比分析其在不同升温速率下从室温升至1000℃的燃烧特性,用Flynn-Wall-Ozawa (FWO)法计算其燃烧过程中的反应动力学参数。结果表明,稻壳水热炭的挥发... 采用热重分析法研究城市污泥、稻壳水热炭及两者不同掺混比的燃烧特性与反应动力学。对比分析其在不同升温速率下从室温升至1000℃的燃烧特性,用Flynn-Wall-Ozawa (FWO)法计算其燃烧过程中的反应动力学参数。结果表明,稻壳水热炭的挥发性、着火和燃尽指数均高于城市污泥,具有较好的燃烧特性,掺混稻壳水热炭使城市污泥混合燃烧时发生热滞后现象。随着稻壳水热炭掺混比的增加,共混物的燃烧残余质量减少,着火性能变差,燃烧性能变强。活化能的相关系数均高于0.95,稻壳水热炭掺混高于50wt%时,共混物的平均活化能低于稻壳水热炭单独燃烧的平均活化能,掺混70wt%稻壳水热炭时出现最低平均活化能,为85.48 k J/mol。城市污泥与稻壳水热炭混燃时有协同交互作用,且掺混50wt%稻壳水热炭时效果最佳。 展开更多
关键词 城市污泥 水热炭 动力学 混合燃烧 活化能
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Deacetylation of TFEB promotes fibrillar Aβ degradation by upregulating lysosomal biogenesis in microglia 被引量:10
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作者 Jintao Bao Liangjun Zheng +11 位作者 Qi zhang Xinya Li xuefei zhang Zeyang Li Xue Bai Zhong zhang Wei Huo Xuyang Zhao Shujiang Shang Qingsong Wang Chen zhang Jianguo Ji 《Protein & Cell》 SCIE CAS CSCD 2016年第6期417-433,共17页
Microglia play a pivotal role in clearance of Aβ by degrading them in lysosomes, countering amyloid pla- que pathogenesis in Alzheimer's disease (AD). Recent evidence suggests that lysosomal dysfunction leads to i... Microglia play a pivotal role in clearance of Aβ by degrading them in lysosomes, countering amyloid pla- que pathogenesis in Alzheimer's disease (AD). Recent evidence suggests that lysosomal dysfunction leads to insufficient elimination of toxic protein aggregates. We tested whether enhancing lysosomal function with transcription factor EB (TFEB), an essential regulator modulating lysosomal pathways, would promote Aβ clearance in microglia. Here we show that microglial expression of TFEB facilitates fibrillar Aβ (fAβ) degra- dation and reduces deposited amyloid plaques, which are further enhanced by deacetylation of TFEB. Using mass spectrometry analysis, we firstly confirmed acetylation as a previously unreported modification of TFEB and found that SIRT1 directly interacted with and deacetylated TFEB at lysine residue 116. Subsequently, SIRT1 overexpression enhanced lysosomal function and fAβ degradation by upregulating transcriptional levels of TFEB downstream targets, which could be inhibited when TFEB was knocked down. Furthermore, overexpression of deacetylated TFEB at K116R mutant in microglia accelerated intracellular fAβ degradation by stimulating lysosomal biogenesis and greatly reduced the deposited amyloid plaques in the brain slices of APPIPS1 transgenic mice. Our findings reveal that deacetylaUon of TFEB could regulate lysosomal biogenesis and fAβ degradation, making microglial activation of TFEB a possible strategy for attenuating amyloid plaque deposition in AD. 展开更多
关键词 Alzheimer's disease microglia lysosomes TFEB SIRT1 DEACETYLATION
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A Novel Ratio-Based Parallel DEA Approach for Evaluating the Energy and Environmental Performance of Chinese Transportation Sectors 被引量:3
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作者 Xiyang Lei Lin Li +2 位作者 xuefei zhang Qianzhi Dai Yelin Fu 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2019年第5期621-635,共15页
As a high-energy-consumption and high-CO2-emission industry in China,the transportation sector has been under increasing pressure to improve its performance.This paper develops a novel parallel DEA approach to measure... As a high-energy-consumption and high-CO2-emission industry in China,the transportation sector has been under increasing pressure to improve its performance.This paper develops a novel parallel DEA approach to measure Chinese transportation sector's energy and environmental performance (EEP) over all possible weights,which is to avoid the risk of using the extreme or the most favorable weights in performance evaluation.In our method,the transportation sector is consisted of two parallel subsystems (passenger transportation and freight transportation) with shared inputs and undesirable shared outputs.All possible weights are considered in the EEP evaluation,then the EEP of a transportation sector is represented by a ranking interval.Finally,the proposed approach is applied to the transportation sectors in 30 Chinese provinces.Results show that the best and the worst ranking of most provinces vary greatly.Besides,the EEP of most provinces is hard to dominate others strictly,but the general tendency is the EEP of eastern provinces better than western provinces.Furthermore,the EEP difference of some adjacent provinces with similar features is distinct.These findings are not all the same as previous studies,which verifies the necessity of considering all possible weights in performance evaluation.Therefore,our method provides a new point of view in performance evaluation and can give more robust results for decision makers. 展开更多
关键词 Data envelopment analysis energy and environmental PERFORMANCE TRANSPORTATION SECTOR PARALLEL system RANKING INTERVAL
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Tackling COVID-19:Insights from the Qinghai Province plague prevention and control(PPC)model 被引量:1
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作者 Haisheng Wu Qingwen zhang +6 位作者 Hailian Wu Fuzhang Tian Baizhong Cui Zhizhen Qi Xiaoqing Xu xuefei zhang HuWang 《Biosafety and Health》 2020年第4期187-192,共6页
Plague,caused by Yersinia pestis,is a natural focus infectious disease.In China,plague is classified as category A,with the highest risk and hazard among the infectious diseases.Qinghai used to be considered as one of... Plague,caused by Yersinia pestis,is a natural focus infectious disease.In China,plague is classified as category A,with the highest risk and hazard among the infectious diseases.Qinghai used to be considered as one of the most serious areas of plague in China.In recent years,thank to the measures in eight aspects summarized as the“Qinghai model”which were adopted to prevent and control the human plague in Qinghai,Qinghai has not experienced any plague case reported for eight years.In early 2020,coronavirus disease 2019(COVID-19)outbroke in China.The Qinghai model on plague was employed to deal with the COVID-19 emergency in Qinghai Province.The Qinghai Center for Disease Control and Prevention(Qinghai CDC)and hospitals,along with the departments of public security,animal husbandry and other departments,quickly tracked and treated the patients with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and started surveillance programs on close contacts timely.At present,the cure rate of patients has reached 100%,and close contacts have been effectively quarantined and tested to avoid the spread of COVID-19.The findings from the study suggest that the prevention and control measures undertaken in Qinghai Province might be effective in dealing with the category A infectious diseases such as COVID-19 and other diseases. 展开更多
关键词 PLAGUE COVID-19 Qinghai model Public health
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A multifunctional cholesterol-free liposomal platform based on protopanaxadiol for alopecia therapy
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作者 xuefei zhang Shuxuan Li +3 位作者 Yating Dong Hehui Rong Junke Zhao Haiyan Hu 《Nano Research》 SCIE EI CSCD 2022年第10期9498-9510,共13页
Liposome could form a long-term drug reservoir in the skin for sustained drug release,which is beneficial to improving efficacy and alleviating adverse effects.Thus,it has become a better option for anti-alopecia drug... Liposome could form a long-term drug reservoir in the skin for sustained drug release,which is beneficial to improving efficacy and alleviating adverse effects.Thus,it has become a better option for anti-alopecia drugs delivery.However,cholesterol used as the fluidity buffer in conventional liposomes is a precursor for testosterone biosynthesis,which could convert to dihydrotestosterone,resulting in hair follicle damage and potentiating hair loss.To overcome the limitations,in this study we prepared a cholesterol-free liposome(PPD-Lip)using protopanaxadiol(PPD)instead of cholesterol to avoid the biosynthesis of testosterone which is adverse to alopecia therapy.PPD-Lip also worked as an active ingredient to facilitate hair growth by promoting dermal papilla cells proliferation and migration,upregulating mRNA levels of hair growth-related positive regulators,and accelerating angiogenesis in vitro.Meanwhile,it promoted hair regrowth in telogen and androgenetic alopecia mice models in vivo.In addition,our study showed that as the liposomal vehicle,PPD-Lip loaded with dutasteride exerted a stronger efficacy in the treatment of androgenetic alopecia and such a strategy could extend to other anti-alopecia agents.To the best of our knowledge,being easy for clinical transformation,the PPD-based liposomal delivery system provides a promising and multifunctional alternative platform for the delivery of alopecia treatment agents. 展开更多
关键词 PROTOPANAXADIOL cholesterol-free liposomal platform alopecia treatment MULTIFUNCTION
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