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低温等离子体活化液对血管内皮细胞增殖和血管生成能力的影响
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作者 袁网 王香妮 +5 位作者 刘进仁 王曦迎 鹿佳佳 何芷柔 许玉琳 石兴民 《西安交通大学学报(医学版)》 CAS CSCD 北大核心 2024年第3期388-395,共8页
目的探索低温等离子体(low temperature plasma,LTP)产生的活化液(plasma-activated medium,PAM)对人脐静脉血管内皮细胞(human umbilical vein endothelial cells,HUVECs)增殖和血管生成的影响,为未来利用PAM促进创伤愈合和抑制肿瘤血... 目的探索低温等离子体(low temperature plasma,LTP)产生的活化液(plasma-activated medium,PAM)对人脐静脉血管内皮细胞(human umbilical vein endothelial cells,HUVECs)增殖和血管生成的影响,为未来利用PAM促进创伤愈合和抑制肿瘤血管生成提供理论基础。方法选择HUVECs作为体外研究模型,以LTP处理不同时间(0、15、30、45、60、75 s)后的PAM培养液进行分组干预。采用MTT法和细胞周期法测定PAM对HUVECs活力的影响,通过血管生成实验检测PAM对血管生成的影响,采用荧光探针检测细胞内活性氧(ROS)水平;构建黑色素瘤小鼠模型,免疫组织化学法检测肿瘤组织中CD31的表达以评估血管生成情况。结果LTP处理获得的PAM对HUVECs血管生成具有双向作用,表现为:与对照组(0 s)相比,低剂量(15 s和30 s)处理时,HUVEC细胞活力增加,而高剂量(45 s、60 s和75 s)处理时,细胞活力明显下降(P<0.05);PAM-15 s和PAM-30 s组处于S期的细胞比例明显增高,而PAM-45 s、PAM-60 s、PAM-75 s组处于S期细胞比例显著降低,差异具有统计学意义(P<0.05);PAM-15 s和PAM-30 s组HUVEC血管生成能力增强,而PAM-45 s、PAM-60 s、PAM-75 s组的细胞血管生成能力降低,血管节点、交叉点、网眼数和血管分支数都明显降低(P<0.05)。此外,HUVECs内ROS水平随着LTP处理时间的延长而升高。PAM处理黑色素瘤小鼠后,对照组肿瘤组织中CD31棕黄色阳性信号大面积分布,各PAM处理组肿瘤组织中CD31棕黄色颗粒分布减少。结论短时间LTP处理的PAM促进了HUVEC的增殖和血管生成;而长时间LTP处理的PAM则抑制细胞活力和血管生成。 展开更多
关键词 低温等离子体 血管内皮细胞 血管生成
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供应链数字化转型对企业盈利的影响研究——机制分析、驱动渠道的差异与异质性特征
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作者 卢志平 苑望 +1 位作者 朱晓琴 孙梦洁 《供应链管理》 2024年第8期86-98,共13页
数字经济时代,供应链数字化转型对提升企业竞争力,促进我国经济高质量发展具有重要作用。基于2012—2021年我国A股上市企业的面板数据,利用供应链创新与应用试点工作中的试点企业样本构建双重差分模型,实证研究了供应链数字化转型程度... 数字经济时代,供应链数字化转型对提升企业竞争力,促进我国经济高质量发展具有重要作用。基于2012—2021年我国A股上市企业的面板数据,利用供应链创新与应用试点工作中的试点企业样本构建双重差分模型,实证研究了供应链数字化转型程度对企业盈利能力的影响和作用机制。研究发现,数字化供应链显著提升了企业盈利能力,采用替换被解释变量、更换试点企业、剔除自治区样本、加入控制变量和倾向得分匹配等方法进行稳健性检验后,此结论依然成立;机制分析发现,数字化供应链通过降低管理成本、提升供需匹配精准度来提升企业盈利能力。虽然战略引领和技术进步都可以驱动数字化供应链建设,但对比来讲战略则更加重要;异质性分析结果表明,数字化供应链的赋能效应在东部地区、制造业企业和外部创新环境较好的企业中更加显著。企业应从战略层面出发,将数字化供应链建设作为提升竞争力和实现高质量发展的重要战略举措;政府可以针对地区、企业和行业的特性采取个性化措施,营造良好的创新环境和供应链运营环境,切实提升产业链供应链现代化水平。 展开更多
关键词 数字化供应链 盈利能力 管理成本 供应链效率
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金宝Prismaflex连续性肾脏替代治疗设备运行原理与故障案例分析 被引量:1
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作者 袁望 何潇玲 +2 位作者 寿嫣薇 马军 李洁 《中国医学装备》 2024年第3期178-181,共4页
分析金宝Prismaflex连续性肾脏替代治疗(CRRT)机的设计原理和治疗模式,基于设备的基本结构与治疗流程解析CRRT设备出现的压力接头和秤归零测试失败的典型故障案例,提出针对性解决方案及维护保养策略,保障CRRT机稳定高效运行。
关键词 连续性肾脏替代治疗(CRRT) 压力接头 故障 维护保养
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低温诱导基因表达与紫花苜蓿主要农艺性状间的关系
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作者 彭嘉文 夏厚胤 +9 位作者 马志超 崔祎琳 苑旺 苗愉祺 同雨涛 武佳昕 张梦瑶 袁子昂 高景慧 杨培志 《草地学报》 CAS CSCD 北大核心 2024年第11期3358-3370,共13页
低温限制紫花苜蓿(Medicago sativa L.)生长发育,严重影响其产量。为在作物生长早期筛选高产抗寒候选品种,本研究以4种紫花苜蓿为试验材料,利用甲基磺酸乙酯(Ethyl methanesulfonate,EMS)诱变建立T 1突变群体,结合优良突变体高产相关农... 低温限制紫花苜蓿(Medicago sativa L.)生长发育,严重影响其产量。为在作物生长早期筛选高产抗寒候选品种,本研究以4种紫花苜蓿为试验材料,利用甲基磺酸乙酯(Ethyl methanesulfonate,EMS)诱变建立T 1突变群体,结合优良突变体高产相关农艺性状评价,拟探索低温诱导基因表达量与高产农艺性状间的关系。结果表明:优质抗寒苜蓿突变体植株表现为植株高大、茎秆粗壮、分枝数多、叶面积大,同时低温诱导基因MsG0180003510(HIPP),MsG0880047253(LEA),MsG0880047531(TPS)和MsG0180005121(PM)表达水平在隶属函数分析中排位最高;其中HIPP与茎粗显著正相关(P<0.05),LEA与茎粗显著正相关、与分枝数和节间显著负相关(P<0.05),PM和茎粗、分枝数和干鲜重显著正相关(P<0.05)。研究指出苜蓿中农艺性状表现为茎秆粗壮、枝繁叶茂,且分子水平HIPP,LEA,TPS和PM基因高表达,可作为在生长早期筛选高产耐寒苜蓿品种的预测因子,为紫花苜蓿在低温胁迫下的生存策略提供依据。 展开更多
关键词 紫花苜蓿 低温胁迫 农艺性状 低温诱导基因
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The Probability Density Function Related to Shallow Cumulus Entrainment Rate and Its Influencing Factors in a Large-Eddy Simulation 被引量:3
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作者 Lei ZHU Chunsong LU +5 位作者 Xiaoqi XU Xin HE Junjun LI Shi LUO yuan wang Fan wang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期173-187,共15页
The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus clouds.Accurately obtaining the entrainment rate(λ)is particularly important for its parameteri... The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus clouds.Accurately obtaining the entrainment rate(λ)is particularly important for its parameterization within the overall cumulus parameterization scheme.In this study,an improved bulk-plume method is proposed by solving the equations of two conserved variables simultaneously to calculateλof cumulus clouds in a large-eddy simulation.The results demonstrate that the improved bulk-plume method is more reliable than the traditional bulk-plume method,becauseλ,as calculated from the improved method,falls within the range ofλvalues obtained from the traditional method using different conserved variables.The probability density functions ofλfor all data,different times,and different heights can be well-fitted by a log-normal distribution,which supports the assumed stochastic entrainment process in previous studies.Further analysis demonstrate that the relationship betweenλand the vertical velocity is better than other thermodynamic/dynamical properties;thus,the vertical velocity is recommended as the primary influencing factor for the parameterization ofλin the future.The results of this study enhance the theoretical understanding ofλand its influencing factors and shed new light on the development ofλparameterization. 展开更多
关键词 large-eddy simulation cumulus clouds entrainment rate probability density functions spatial and temporal distribution
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多波段FMCW雷达低慢小探测数据集(LSS-FMCWR-1.0)及高分辨微动特征提取方法 被引量:2
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作者 陈小龙 袁旺 +4 位作者 杜晓林 于刚 何肖阳 关键 汪兴海 《雷达学报(中英文)》 EI CSCD 北大核心 2024年第3期539-553,共15页
无人机等低慢小目标探测对雷达目标检测和识别技术提出了很高的挑战,迫切需要构建相关数据集,支撑低慢小探测技术的发展和应用。该文公开了一个多波段调频连续波(FMCW)雷达低慢小目标探测数据集,基于Ku波段和L波段的FMCW雷达采集6种类... 无人机等低慢小目标探测对雷达目标检测和识别技术提出了很高的挑战,迫切需要构建相关数据集,支撑低慢小探测技术的发展和应用。该文公开了一个多波段调频连续波(FMCW)雷达低慢小目标探测数据集,基于Ku波段和L波段的FMCW雷达采集6种类型的无人机回波数据,通过雷达调制周期和调制带宽,具备不同时域和频域分辨和测量能力,构建了多波段FMCW雷达低慢小探测数据集(LSS-FMCWR-1.0)。为了进一步提升无人机微动特征提取能力,该文提出基于局部极大值同步提取变换的无人机微动提取和参数估计方法,在短时傅里叶变换的基础上提取时频能量最大值,保留有用信号分量,实现精细化时频表示。基于LSS-FMCWR-1.0进行验证分析,结果表明该方法相较于传统时频方法,熵值平均降低了5.3 dB,旋翼叶长估计误差降低了27.7%,所提方法兼顾高时频分辨率和较高的参数估计精度,为后续目标识别奠定了基础。 展开更多
关键词 低慢小目标 调频连续波雷达 微动特性 局部极大值同步提取变换 公开数据集
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New insights on the high-corrosion resistance of UHP Mg-Ge alloys tested in a simulated physiological environment 被引量:1
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作者 Ting Liu Xingrui Chen +4 位作者 Jeffrey Venezuela yuan wang Zhiming Shi Wenyi Chen Matthew Dargusch 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1026-1044,共19页
UHP Mg-Ge alloys was recently found to provide excellent corrosion resistance.This paper provides new insights on the mechanism of improved corrosion resistance of UHP Mg-Ge alloys in Hanks’solution.The studied UHP M... UHP Mg-Ge alloys was recently found to provide excellent corrosion resistance.This paper provides new insights on the mechanism of improved corrosion resistance of UHP Mg-Ge alloys in Hanks’solution.The studied UHP Mg-0.5Ge and UHP Mg-1Ge alloys showed superior corrosion resistance compared to UHP Mg and WE43,with the Mg-1Ge exhibiting the best corrosion performance.The exceptional corrosion resistance of the UHP alloy is attributed to(i)Mg_(2)Ge’s ability to suppress cathodic kinetics,(ii)Ge’s capability to accelerate the formation of a highly passive layer,and the(iii)low amounts of corrosion-accelerating impurities. 展开更多
关键词 UHP Mg-Ge alloy Cathodic kinetics suppression Biodegradable metals In vitro corrosion Magnesium corrosion.
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GbLMI1 over-expression improves cotton aboveground vegetative growth 被引量:1
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作者 Zhili Chong Yunxiao Wei +7 位作者 Kaili Li Muhammad Aneeq Ur Rahman Chengzhen Liang Zhigang Meng yuan wang Sandui Guo Liangrong He Rui Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3457-3467,共11页
Leaves are the main organ for photosynthesis and organic synthesis in cotton.Leaf shape has important effects on photosynthetic efficiency and canopy formation,thereby affecting cotton yield.Previous studies have show... Leaves are the main organ for photosynthesis and organic synthesis in cotton.Leaf shape has important effects on photosynthetic efficiency and canopy formation,thereby affecting cotton yield.Previous studies have shown that LMI1(LATE MERISTEM IDENTITY1)is the main gene regulating leaf shape.In this study,the LMI1 gene was inserted into the 35S promoter expression vector,and cotton plants overexpressing LMI1(OE)were obtained through genetic transformation.Statistical analysis of the biological traits of the T_(1) and T_(2) populations showed that compared to the wild type(WT),OE plants had significantly larger leaves,thicker stems and significantly greater dry weight.Furthermore,plant sections of the main vein and petiole showed that the numbers of cells in those tissues of OE plants were significantly greater.In addition,RNA-seq analysis revealed the differential expression of genes related to gibberellin synthesis and NAC gene family(genes containing the NAC domain)between the OE and WT plants,suggesting that LMI1 is involved in secondary wall formation and cell proliferation,which promotes stem thickening.Moreover,Gene Ontology(GO)analysis revealed enrichment in the terms of calcium ion binding,and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis showed enrichment in the terms of fatty acid degradation,phosphatidylinositol signal transduction system,and c AMP(cyclic adenosine monophosphate)signal pathway.These results suggested that LMI1 OE plants are responsive to gibberellin hormone signals,and have altered messenger signals(c AMP,Ca^(2+))which amplify this function,to promote stronger aboveground vegetative growth.This study found the LMI1 greatly increased the vegetative growth in cotton,which is the basic requirement for higher yield. 展开更多
关键词 LMI1 over-expressing COTTON vegetative growth
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基于β-环糊精的高矿化度水中曲拉通X-405的检测新方法
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作者 孙建萧 荆江录 +3 位作者 王渊 樊庆虎 肖文梁 石东坡 《日用化学工业(中英文)》 CAS 北大核心 2024年第4期369-375,共7页
油田压裂用水矿化度高,为了降低压裂用水对紫外光谱法检测聚乙二醇叔辛基苯基醚(曲拉通X-405)产生的影响,采用添加适量β-环糊精(β-CD)作为屏蔽剂来消除压裂用水的干扰作用。研究结果表明,压裂用水能明显降低曲拉通X-405的吸光度和临... 油田压裂用水矿化度高,为了降低压裂用水对紫外光谱法检测聚乙二醇叔辛基苯基醚(曲拉通X-405)产生的影响,采用添加适量β-环糊精(β-CD)作为屏蔽剂来消除压裂用水的干扰作用。研究结果表明,压裂用水能明显降低曲拉通X-405的吸光度和临界胶束浓度(cmc),在压裂用水中,100.0 mg/L曲拉通X-405在最大吸收波长224 nm处的吸光度降幅达6.67%,曲拉通X-405的cmc也由蒸馏水中的103.978 mg/L降低至97.056 mg/L。加入与曲拉通X-405相同物质的量的β-环糊精后,压裂用水对曲拉通X-405吸光度的干扰作用显著降低,100.0 mg/L曲拉通X-405在224 nm处的吸光度降幅仅为1.99%,在20.0~160.0 mg/L范围内,曲拉通X-405在蒸馏水中及在压裂用水中均没有形成胶束,曲拉通X-405的检测回收率也由88.3%~97.4%改善至97.5%~99.6%。等摩尔连续变化法、FT IR及^(1)H NMR结果表明,在水溶液中曲拉通X-405与β-CD按物质的量比1∶1形成包结物,曲拉通X-405分子可以分别从β-CD分子空腔的宽、窄口径两端进入β-CD内腔,包结物的屏蔽作用是降低压裂用水对曲拉通X-405的干扰作用的根本原因。该方法为准确检测高矿化度压裂用水中的曲拉通X-405提供了新参考。 展开更多
关键词 曲拉通X-405 Β-环糊精 压裂用水 定量 干扰
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交通安全隐患排查与治理研究——以武汉市为例
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作者 周进 赵欣 袁旺 《武汉公安干部学院学报》 2024年第3期17-22,共6页
交通安全是社会发展中一个重要的问题,而交通安全隐患排查是确保交通安全的重要环节。通过对交通安全隐患排查的相关理论进行分析,结合实际案例,探讨了交通安全隐患排查的重要性和必要性。通过对交通事故的统计分析发现,大部分交通事故... 交通安全是社会发展中一个重要的问题,而交通安全隐患排查是确保交通安全的重要环节。通过对交通安全隐患排查的相关理论进行分析,结合实际案例,探讨了交通安全隐患排查的重要性和必要性。通过对交通事故的统计分析发现,大部分交通事故是由于交通安全隐患导致的。因此,对交通安全隐患进行排查和整改是提高交通安全水平的关键。最后,提出了提高交通安全隐患排查效率的建议,以期为交通安全管理工作提供参考。 展开更多
关键词 交通安全 交通事故 隐患排查 安全管理
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Liquid injectivity in a SAG foam process:Effect of permeability
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作者 Jia-Kun Gong yuan wang +4 位作者 Ridhwan-Zhafri B.Kamarul Bahrim Raj-Deo Tewari Mohammad-Iqbal Mahamad Amir Rouhi Farajzadeh William Rossen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期302-314,共13页
Foam is utilized in enhanced oil recovery and CO_(2) sequestration.Surfactant-alternating-gas(SAG)is a preferred approach for placing foam into reservoirs,due to it enhances gas injection and minimizes corrosion in fa... Foam is utilized in enhanced oil recovery and CO_(2) sequestration.Surfactant-alternating-gas(SAG)is a preferred approach for placing foam into reservoirs,due to it enhances gas injection and minimizes corrosion in facilities.Our previous studies with similar permeability cores show that during SAG injection,several banks occupy the area near the well where fluid exhibits distinct behaviour.However,underground reservoirs are heterogeneous,often layered.It is crucial to understand the effect of permeability on fluid behaviour and injectivity in a SAG process.In this work,coreflood experiments are conducted in cores with permeabilities ranging from 16 to 2300 mD.We observe the same sequence of banks in cores with different permeabilities.However,the speed at which banks propagate and their overall mobility can vary depending on permeability.At higher permeabilities,the gas-dissolution bank and the forced-imbibition bank progress more rapidly during liquid injection.The total mobilities of both banks decrease with permeability.By utilizing a bank-propagation model,we scale up our experimental findings and compare them to results obtained using the Peaceman equation.Our findings reveal that the liquid injectivity in a SAG foam process is misestimated by conventional simulators based on the Peaceman equation.The lower the formation permeability,the greater the error. 展开更多
关键词 Foam Enhanced oil recovery Surfactant-alternating-gas INJECTIVITY PERMEABILITY
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Force Compensation Control for Electro-Hydraulic Servo System with Pump-Valve Compound Drive via QFT-DTOC
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作者 Kaixian Ba yuan wang +4 位作者 Xiaolong He Chunyu wang Bin Yu Yaliang Liu Xiangdong Kong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期228-246,共19页
Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ratio.However,most HDUs are throttling-valve-controlled cylinder systems,which exhi... Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ratio.However,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy losses.By contrast,pump control systems offer a high efficiency.Nevertheless,their response ability is unsatisfactory.To fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of robots.Herein,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDS force control system is first introduced.In addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC herein.This method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the system.Finally,experimental verification is performed using the PCDS performance test platform.The experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the PCDS.The relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot. 展开更多
关键词 Legged robot Pump-valve compound drive system(PCDS) Force compensation control Quantitative feedback theory(QFT) Disturbance torque observer(DTO)
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Modification,application and expansion of electrode materials based on cobalt telluride
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作者 Huilin Fan Yao Dai +7 位作者 Xiaoyun Xue Runguo Zheng yuan wang Hamidreza Arandiyan Zhiyuan wang Zongping Shao Hongyu Sun Yanguo Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期710-737,I0015,共29页
Metal(Li,Na,K,Al)-ion batteries and lithium-sulfur and lithium-tellurium batteries are gaining recognition for their eco-friendly characteristics,substantial energy density,and sustainable attributes.However,the overa... Metal(Li,Na,K,Al)-ion batteries and lithium-sulfur and lithium-tellurium batteries are gaining recognition for their eco-friendly characteristics,substantial energy density,and sustainable attributes.However,the overall performance of rechargeable batteries heavily depends on their electrode materials.Transition metal tellurides have recently gained significant attention due to their high electrical conductivity and density.Cobalt telluride has received the most extensive research due to its catalytic activity,unique magnetic properties,and diverse composition and crystal structure.Nevertheless,its limited conductivity and significant volume variation contribute to electrode structural deterioration and rapid capacity decline.This review comprehensively summarizes recent advances in rational design and synthesis of modified cobalt telluride-based electrodes,encompassing defect engineering(Te vacancies,cation vacancies,heterointerfaces,and homogeneous interfaces)and composite engineering(derived carbon from precursors,carbon fibers,Mxene,graphene nanosheets,etc.).Particularly,the intricate evolution mechanisms of the conversion reaction process during cycling are elucidated.Furthermore,these modified strategies applied to other transitional metal tellurides,such as iron telluride,nickel telluride,zinc telluride,copper telluride,molybdenum telluride,etc.,are also thoroughly summarized.Additionally,their application extends to emerging aqueous zinc-ion batteries.Finally,potential challenges and prospects are discussed to further propel the development of transition metal tellurides electrode materials for next-generation rechargeable batteries. 展开更多
关键词 Rechargeable batteries Transition metal tellurides Cobalt telluride Defect engineering Composite engineering
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可生物降解塑料取代传统塑料--对碳排放的影响
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作者 Guanyi Chen Jianyuan Li +11 位作者 Yunan Sun Zhi wang Gary ALeeke Christian Moretti Zhanjun Cheng yuan wang Ning Li Lan Mu Jinyu Li Junyu Tao Beibei Yan Li'an Hou 《Engineering》 SCIE EI CAS CSCD 2024年第1期152-162,共11页
In recent years,a great deal of attention has been focused on the environmental impact of plastics,includ-ing the carbon emissions related to plastics,which has promoted the application of biodegradable plas-tics.Coun... In recent years,a great deal of attention has been focused on the environmental impact of plastics,includ-ing the carbon emissions related to plastics,which has promoted the application of biodegradable plas-tics.Countries worldwide have shown high interest in replacing traditional plastics with biodegradable plastics.However,no systematic comparison has been conducted on the carbon emissions of biodegrad-able versus traditional plastic products.This study evaluates the carbon emissions of traditional and biodegradable plastic products(BPPs)over four stages and briefly discusses environmental and economic perspectives.Four scenarios-namely,the traditional method,chemical recycling,industrial composting,and anaerobic digestion-are considered for the disposal of waste BPPs(WBPPs).The analysis takes China as a case study.The results show that the carbon emissions of 1000traditional plastic products(plastic bags,lunch boxes,cups,etc.)were52.09-150.36 carbon emissions equivalent of per kilogram(kg CO_(2)eq),with the stage of plastic production contributing 50.71%-50.77%.In comparison,1000 similar BPPs topped out at 21.06-56.86 kg CO_(2)eq,approximately 13.53%-62.19%lower than traditional plastic prod-ucts.The difference was mainly at the stages of plastic production and waste disposal,and the BPPs showed significant carbon reduction potential at the raw material acquisition stage.Waste disposal plays an important role in environmental impact,and composting and anaerobic digestion are considered to be preferable disposal methods for WBPPs.However,the high cost of biodegradable plastics is a challenge for their widespread use.This study has important reference significance for the sustainable development of the biodegradableplastics industry. 展开更多
关键词 Carbon emissions Biodegradable plastics Different disposal scenarios Daily life consumption Environmental and economic discussion
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Toward Artificial Peptide Nanocapsules
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作者 yuan wang Bing Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期240-243,共4页
HIGHLIGHTS The formation of peptide nanocapsules is facilitated by a gradient interface,where the differential solvent concentration drives the peptides to preferentially localize and assemble.The peptide nanocapsules... HIGHLIGHTS The formation of peptide nanocapsules is facilitated by a gradient interface,where the differential solvent concentration drives the peptides to preferentially localize and assemble.The peptide nanocapsules,characterized by their hollow structures,demonstrated potential as carriers for targeted drug delivery.1 Introduction Peptide nanocapsules are a type of nanoscale delivery system that encapsulates active substances within a shell composed of peptides,leveraging the unique properties of peptides such as biocompatibility and biodegradability[1].Historically,the development of peptide nanocapsules was inspired primordially by the natural biological processes. 展开更多
关键词 Peptide nanocapsules SELF-ASSEMBLY Drug delivery NANOMEDICINE
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Tunable spectral continuous shift of high-order harmonic generation in atoms by a plasmon-assisted shaping pulse
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作者 王源 李玉龙 +7 位作者 乔月 高娜 郭福明 陈洲 赫兰海 杨玉军 赵曦 王俊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期433-440,共8页
We delve into the phenomenon of high-order harmonic generation within a helium atom under the influence of a plasmon-assisted shaping pulse.Our findings reveal an intriguing manipulation of the frequency peak position... We delve into the phenomenon of high-order harmonic generation within a helium atom under the influence of a plasmon-assisted shaping pulse.Our findings reveal an intriguing manipulation of the frequency peak position in the harmonic emission by adjusting the absolute phase parameter within the frequency domain of the shaping pulse.This phenomenon holds potential significance for experimental setups necessitating precisely tuned single harmonics.Notably,we observe a modulated shift in the created harmonic photon energy,spanning an impressive range of 1.2 eV.This frequency peak shift is rooted in the asymmetry exhibited by the rising and falling edges of the laser pulse,directly influencing the position of the peak frequency emission.Our study quantifies the dependence of this tuning range and the asymmetry of the laser pulse,offering valuable insights into the underlying mechanisms driving this phenomenon.Furthermore,our investigation uncovers the emergence of semi-integer order harmonics as the phase parameter is altered.We attribute this discovery to the intricate interference between harmonics generated by the primary and secondary return cores.This observation introduces an innovative approach for generating semi-integer order harmonics,thus expanding our understanding of high-order harmonic generation.Ultimately,our work contributes to the broader comprehension of complex phenomena in laser-matter interactions and provides a foundation for harnessing these effects in various applications,particularly those involving precise spectral control and the generation of unique harmonic patterns. 展开更多
关键词 high-order harmonic semi-integer-order spectra shift inhomogeneous field
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Track-Pattern-Based Characteristics of Extratropical Transitioning Tropical Cyclones in the Western North Pacific
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作者 Hong HUANG Dan WU +2 位作者 yuan wang Zhen wang Yu LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1251-1263,共13页
Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacif... Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacific(WNP)during 1951–2021 are classified into six clusters using the fuzzy c-means clustering method(FCM)according to their track patterns.The characteristics of the six hard-clustered ETCs with the highest membership coefficient are shown.Most tropical cyclones(TCs)that were assigned to clusters C2,C5,and C6 made landfall over eastern Asian countries,which severely threatened these regions.Among landfalling TCs,93.2%completed their ET after landfall,whereas 39.8%of ETCs completed their transition within one day.The frequency of ETCs over the WNP has decreased in the past four decades,wherein cluster C5 demonstrated a significant decrease on both interannual and interdecadal timescales with the expansion and intensification of the western Pacific subtropical high(WPSH).This large-scale circulation pattern is favorable for C2 and causes it to become the dominant track pattern,owning to it containing the largest number of intensifying ETCs among the six clusters,a number that has increased insignificantly over the past four decades.The surface roughness variation and three-dimensional background circulation led to C5 containing the maximum number of landfalling TCs and a minimum number of intensifying ETCs.Our results will facilitate a better understanding of the spatiotemporal distributions of ET events and associated environment background fields,which will benefit the effective monitoring of these events over the WNP. 展开更多
关键词 Western North Pacific tropical cyclone extratropical transition fuzzy c-means clustering method
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Research advances on encapsulation of probiotics with nanomaterials and their repair mechanisms on intestinal barriers
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作者 Xiaochen wang Mengxi Yu +7 位作者 Jianming Ye Ting Liu Lijuan Jian Xiaoyan Zheng yuan wang Wei Song Yane Luo Tianli Yue 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3095-3109,共15页
Probiotics participate in various physiological activities and contribute to body health.However,their viability and bioefficacy are adversely affected by gastrointestinal harsh conditions,such as gastric acid,bile sa... Probiotics participate in various physiological activities and contribute to body health.However,their viability and bioefficacy are adversely affected by gastrointestinal harsh conditions,such as gastric acid,bile salts and various enzymes.Fortunately,encapsulation based on various nanomaterials shows tremendous potential to protect probiotics.In this review,we introduced some novel encapsulation technologies involving nanomaterials in view of predesigned stability and viability,selective adhesion,smart release and colonization,and efficacy exertion of encapsulated probiotics.Furthermore,the interactions between encapsulated probiotics and the gastrointestinal tract were summarized and analyzed,with highlighting the regulatory mechanisms of encapsulated probiotics on intestinal mechanical barrier,chemical barrier,biological barrier and immune barrier.This review would benefit the food and pharmaceutical industries in preparation and utilization of multifunctional encapsulated probiotics. 展开更多
关键词 PROBIOTICS ENCAPSULATION Environment-responsive release Repair mechanisms Selective colonization
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Low-firing and temperature stability regulation of tri-rutile MgTa_(2)O_(6)microwave dielectric ceramics
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作者 Chengzhi Xu Hongyu Yang +5 位作者 Hongcheng Yang Linzhuang Xing yuan wang Zhimin Li Enzhu Li Guorui Zhao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第8期1935-1943,共9页
A glass frit containing Li_(2)O-MgO-ZnO-B_(2)O_(3)-SiO_(2)component was used to explore the low-temperature sintering behaviors and microwave dielectric characteristics of tri-rutile MgTa_(2)O_(6)ceramics in this stud... A glass frit containing Li_(2)O-MgO-ZnO-B_(2)O_(3)-SiO_(2)component was used to explore the low-temperature sintering behaviors and microwave dielectric characteristics of tri-rutile MgTa_(2)O_(6)ceramics in this study.The good low-firing effects are presented due to the high matching relevance between Li_(2)O-MgO-ZnO-B_(2)O_(3)-SiO_(2)glass and MgTa_(2)O_(6)ceramics.The pure tri-rutile MgTa_(2)O_(6)structure remains unchanged,and high sintering compactness can also be achieved at 1150℃.We found that the Li_(2)O-MgO-ZnO-B_(2)O_(3)-SiO_(2)glass not only greatly improves the low-temperature sintering characteristics of MgTa_(2)O_(6)ceramics but also maintains a high(quality factor(Q)×resonance frequency(f))value while still improving the temperature stability.Typically,great microwave dielectric characteristics when added with 2wt%Li_(2)O-MgO-ZnO-B_(2)O_(3)-SiO_(2)glass can be achieved at 1150℃:dielectric constant,ε_(r)=26.1;Q×f=34267 GHz;temperature coefficient of resonance frequency,τ_(f)=-8.7×10^(-6)/℃. 展开更多
关键词 MgTa_(2)O_(6) CERAMIC microwave dielectric characteristics glass
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Risk Factors and Predictive Nomogram for Survival in Elderly Patients with Brain Glioma
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作者 Zhi-cheng FAN Wen-jian ZHAO +11 位作者 Yang JIAO Shao-chun GUO Yun-peng KOU Min CHAO Na wang Chen-chen ZHOU yuan wang Jing-hui LIU Yu-long ZHAI Pei-gang JI Chao FAN Liang wang 《Current Medical Science》 SCIE CAS 2024年第4期759-770,共12页
Objective To determine the factors that contribute to the survival of elderly individuals diagnosed with brain glioma and develop a prognostic nomogram.Methods Data from elderly individuals(age≥65 years)histologicall... Objective To determine the factors that contribute to the survival of elderly individuals diagnosed with brain glioma and develop a prognostic nomogram.Methods Data from elderly individuals(age≥65 years)histologically diagnosed with brain glioma were sourced from the Surveillance,Epidemiology,and End Results(SEER)database.The dataset was randomly divided into a training cohort and an internal validation cohort at a 6:4 ratio.Additionally,data obtained from Tangdu Hospital constituted an external validation cohort for the study.The identification of independent prognostic factors was achieved through the least absolute shrinkage and selection operator(LASSO)and multivariate Cox regression analysis,enabling the construction of a nomogram.Model performance was evaluated using C-index,ROC curves,calibration plot and decision curve analysis(DCA).Results A cohort of 20483 elderly glioma patients was selected from the SEER database.Five prognostic factors(age,marital status,histological type,stage,and treatment)were found to significantly impact overall survival(OS)and cancer-specific survival(CSS),with tumor location emerging as a sixth variable independently linked to CSS.Subsequently,nomogram models were developed to predict the probabilities of survival at 6,12,and 24 months.The assessment findings from the validation queue indicate a that the model exhibited strong performance.Conclusion Our nomograms serve as valuable prognostic tools for assessing the survival probability of elderly glioma patients.They can potentially assist in risk stratification and clinical decision-making. 展开更多
关键词 elderly brain glioma Surveillance Epidemiology and End Results(SEER) NOMOGRAM prognosis prediction model
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