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Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis 被引量:2
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作者 Xiahong Tang Nan Zheng +8 位作者 Qingming Lin yan you Zheng Gong yangping Zhuang Jiali Wu Yu Wang Hanlin Huang Jun Ke Feng Chen 《Neural Regeneration Research》 SCIE CAS 2025年第4期1103-1123,共21页
Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to impr... Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are unknown.To this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB pathways.Subsequently,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by asphyxia.The results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these effects.To conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning. 展开更多
关键词 bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria NEUROINFLAMMATION oxidative stress PYROPTOSIS reactive oxygen species
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降低铅电解液中铅离子浓度新工艺研究
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作者 闫友 刘勇 +2 位作者 张文强 胡卫文 赵永江 《绿色矿冶》 2025年第2期48-52,共5页
铅电解精炼作为粗铅提纯的关键工序,电解液中铅离子浓度越高,比电阻越大,直流电耗越高,生产成本增加。在不影响铅电解液化学成分的前提下,经过理论分析,本文采用不溶石墨阳极电积法替代传统硫酸沉淀法,降低电解液中铅离子浓度。研究表明... 铅电解精炼作为粗铅提纯的关键工序,电解液中铅离子浓度越高,比电阻越大,直流电耗越高,生产成本增加。在不影响铅电解液化学成分的前提下,经过理论分析,本文采用不溶石墨阳极电积法替代传统硫酸沉淀法,降低电解液中铅离子浓度。研究表明,在电流强度为11000 A,单槽电解液循环量为50 L/min,电积时间为120 h的条件下,电解液中铅离子浓度下降了14.9 g/L,且电积法析出铅的质量优于常规电解析出铅,其中的锑杂质元素含量下降明显。相比传统硫酸沉淀法,不溶石墨阳极电积法的脱铅成本降低了约451元/t。 展开更多
关键词 大极板 铅电解 铅离子浓度 不溶石墨阳极电积 电流效率
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Coordinated regulation of cortical astrocyte maturation by OLIG1 and OLIG2 through BMP7 signaling modulation
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作者 Ziwu Wang Yu Tian +14 位作者 Tongye Fu Feihong yang Jialin Li Lin yang Wen Zhang Wenhui Zheng Xin Jiang Zhejun Xu yan you Xiaosu Li Guoping Liu Yunli Xie Zhengang yang Dashi Qi Zhuangzhi Zhang 《Journal of Genetics and Genomics》 2025年第10期1224-1237,共14页
Astrocyte maturation is crucial for brain function,yet the mechanisms regulating this process remain poorly understood.In this study,we identify the bHLH transcription factors Olig1 and Olig2 as essential coordinators... Astrocyte maturation is crucial for brain function,yet the mechanisms regulating this process remain poorly understood.In this study,we identify the bHLH transcription factors Olig1 and Olig2 as essential coordinators of cortical astrocyte maturation.We demonstrate that Olig1 and Olig2 work synergistically to regulate cortical astrocyte maturation by modulating Bmp7 expression.Genetic ablation of both Olig1 and Olig2 results in defective astrocyte morphology,including reduced process complexity and an immature gene expression profile.Single-cell RNA sequencing reveals a shift towards a less mature astrocyte state,marked by elevated levels of HOPX and GFAP,resembling human astrocytes.Mechanistically,Olig1 and Olig2 bind directly to the Bmp7 enhancer,repressing its expression to promote astrocyte maturation.Overexpression of Bmp7 in vivo replicates the astrocyte defects seen in Olig1/2 double mutants,confirming the critical role of BMP7 signaling in this process.These findings provide insights into the transcriptional and signaling pathways regulating astrocyte development and highlight Olig1 and Olig2 as key regulators of cortical astrocyte maturation,with potential implications for understanding glial dysfunction in neurological diseases. 展开更多
关键词 ASTROCYTE BMP7 Olig1/2 Transcription factor CORTEX
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农用车辆单神经元自适应PID轨迹跟踪控制 被引量:12
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作者 严友 李美 《机械设计与制造》 北大核心 2020年第10期228-231,235,共5页
为了实现复杂环境下的农用车辆路径跟踪控制,提出了基于单神经元自适应PID的路径跟踪控制方法。首先,建立了农用车辆运动学模型和电动助力转向系统模型,为后续的控制算法的设计打下模型基础。其次,设计了单神经元自适应PID控制策略,为... 为了实现复杂环境下的农用车辆路径跟踪控制,提出了基于单神经元自适应PID的路径跟踪控制方法。首先,建立了农用车辆运动学模型和电动助力转向系统模型,为后续的控制算法的设计打下模型基础。其次,设计了单神经元自适应PID控制策略,为了消除频繁控制引起的振荡,根据实际转角控制精度的要求,设置合理死区作为转角跟踪误差,利用带监督的赫步学习规则对神经元进行训练,在Matlab/Simulink环境下构建控制模型。试验和仿真结果表明,基于SNAPID的农用车辆路径跟踪控制精度较高,在直线行驶工况下,最大偏差在3.2cm以内,平均偏差在0.92cm以内;在曲线行驶工况下,最大偏差在4.3cm以内,平均偏差在1.03cm以内。 展开更多
关键词 农用车辆 轨迹跟踪 运动学模型 单神经元自适应 PID控制
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Combined application of the preclosure technique and traction approach facilitates endoscopic full-thickness resection of gastric submucosal tumors
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作者 Qing-Qing Zu yan you +4 位作者 Ai-Zhi Chen Xiu-Rong Wang Si-Han Zhang Feng-Lin Chen Miao Liu 《World Journal of Gastrointestinal Surgery》 2025年第3期79-86,共8页
BACKGROUND Gastrointestinal submucosal tumors(SMTs)mostly grew in the lumen,but also some of the lesions were extraluminal,in which the stomach was the most co-mmon site.Gastrointestinal stromal tumor account for a la... BACKGROUND Gastrointestinal submucosal tumors(SMTs)mostly grew in the lumen,but also some of the lesions were extraluminal,in which the stomach was the most co-mmon site.Gastrointestinal stromal tumor account for a large proportion of SMT.Due to the deep lesion location of gastric SMT,endoscopic submucosal dissection related techniques are difficult to operate,while endoscopic full-thickness rese-ction(EFTR)has been widely used in clinical practice because it is less invasive and can preserve the physiological structure and function of the stomach.Ho-wever,complete closure of the gastrectomy site after EFTR is critical.If the closure is incomplete,it may cause peritonitis,late perforation and other conditions,and even require further surgical intervention.Although there are currently a number of suture devices and techniques that can be used to promote closure,they have the problem of requiring additional equipment or being inconvenient to use.Although metal clips are widely used,their effectiveness depends on the size and tension of the defect.Therefore,an effective and convenient endoscopic closure technique is urgently needed to solve the closure problem of gastric SMTs after treatment.AIM To investigate the effect of combined application of the preclosure technique and dental floss traction in gastric wound closure following EFTR.METHODS In this study,the data of 94 patients treated for gastric SMTs at the Gastrointestinal Endoscopy Center of the Affiliated Union Hospital of Fujian Medical University from April 2022 to May 2023 were retrospectively analyzed.The patients were divided into a preclosure group(54 patients)and a non-preclosure group(40 patients)on the basis of the timing of wound closure with titanium clips after dental floss traction-assisted EFTR.Each patient in the preclosure group had their wounds preclosed with titanium clips after subtotal lesion resection,whereas each patient in the non-preclosure group had their wounds closed with titanium clips after total lesion resection.The lesion size,wound closure time,number of titanium clips used,incidence of postoperative complications,and postoperative hospitalization time were compared between the two groups.RESULTS The wound closure time was significantly shorter in the preclosure group than in the non-preclosure group(6.69±2.109 minutes vs 11.65±3.786 minutes,P<0.001).The number of titanium clips used was significantly lower in the preclosure group(8.93±2.231)than in the non-preclosure group(12.05±4.495)(P<0.001).There was no sig-nificant difference between the two groups in terms of the need for an indwelling gastric tube or the length of postoperative hospital stay(6.41±1.31 vs 6.13±1.06 days).For all patients in the preclosure group and the non-preclosure group,resection was completed successfully without bleeding,abdominal pain,abdominal distension,or other postoperative complications.CONCLUSION Application of the preclosure technique combined with dental floss traction can be used intraoperatively to effectively close the surgical wound in patients undergoing EFTR,reliably preventing the tumor from falling into the peritoneal cavity. 展开更多
关键词 Gastric submucosal tumor Dental floss traction Endoscopic full-thickness resection Preclosure technique
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独立存取双层俯仰停车库设计
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作者 严友 徐云青 李美 《内燃机与配件》 2021年第1期190-192,共3页
通过研究市场上已有的立体停车库,设计出一款双层俯仰停车库以应对目前越来越严峻的城市停车问题。此项设计采用双层式布局,由一套液压系统提供动力,通过杠杆机构实现车库整体的俯仰运动。改变车库的俯、仰状态实现上下层存车和取车的... 通过研究市场上已有的立体停车库,设计出一款双层俯仰停车库以应对目前越来越严峻的城市停车问题。此项设计采用双层式布局,由一套液压系统提供动力,通过杠杆机构实现车库整体的俯仰运动。改变车库的俯、仰状态实现上下层存车和取车的功能。上下层存取车为两个独立的操作,无论下层是否有车,均不会影响上层的操作,全过程上下层互不干扰。此外,在考虑了车主日常存取车习惯的前提下,还设计有一套控制系统,上下层分别有两套按钮开关,可以实现一键存车、一键取车的操作,整个过程方便快捷。 展开更多
关键词 双层车库 独立存取 结构设计
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底吹炉下料口炉结智能化处理机器人系统研究与应用 被引量:3
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作者 闫友 胡卫文 +5 位作者 申群友 刘辉 马双 谭傲峰 阳自霖 杨正华 《有色金属(冶炼部分)》 CAS 北大核心 2024年第7期46-54,96,共10页
富氧底吹熔炼是国际先进的一种主流熔炼技术,底吹熔炼炉在熔化过程中,炉膛内的跳渣会导致下料口处形成炉结,影响物料进入炉体的流动。现有的炉结处理方法是人工根据运行情况不定期地对入料口进行清理,现场作业环境温度高、粉尘大、工人... 富氧底吹熔炼是国际先进的一种主流熔炼技术,底吹熔炼炉在熔化过程中,炉膛内的跳渣会导致下料口处形成炉结,影响物料进入炉体的流动。现有的炉结处理方法是人工根据运行情况不定期地对入料口进行清理,现场作业环境温度高、粉尘大、工人劳动强度大。阐述了一种机器人系统,能完成底吹炉下料口炉结的智能化处理,系统基于视觉AI感知、三维建模和力控传感等多技术融合的特种机器人清理技术,通过自主研发设计的末端力控风镐完成下料口炉结的清理作业,并已在湖南某铅冶炼厂现场运行。本系统对于底吹炉下料口炉结的识别准确率高,处理炉结的效率快、一致性好,有效减少了炉结的形成及下料口堵塞,提高了富氧底吹熔炼的整体效能和作业的安全性。 展开更多
关键词 底吹熔炼炉 下料口 堵塞 机器人 视觉感知 力控风镐
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基于在线品位数据的铅锌选矿生产优化方法 被引量:1
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作者 闫友 陈福禄 +3 位作者 胡卫文 左昌虎 黄华礼 阳自霖 《有色金属(选矿部分)》 CAS 2024年第6期86-93,共8页
在有色金属浮选生产过程中,自动化、智能化技术手段的应用已成为不可或缺的关键环节,准确、及时地获取浮选流程中不同节点的目标矿物品位是实现泡沫浮选过程实时高效控制的前提。某铅锌矿石复杂多金属的综合回收是一种典型的多目标优化... 在有色金属浮选生产过程中,自动化、智能化技术手段的应用已成为不可或缺的关键环节,准确、及时地获取浮选流程中不同节点的目标矿物品位是实现泡沫浮选过程实时高效控制的前提。某铅锌矿石复杂多金属的综合回收是一种典型的多目标优化问题,针对问题提出一种基于在线品位数据的铅锌选矿生产优化方法。首先,在深入研究矿石矿物组成的基础上,结合多年的生产数据,分析金属元素品位与金属回收率之间的关系,重点分析金、银回收率与铅锌等可被在线检测元素之间的分布规律,明确多金属回收优化问题描述以及在线品位分析仪实时检测的重要性,确定了实现多金属综合回收最优的控制方向。然后,通过利用X荧光在线品位分析系统实时获取关键工艺点主要元素铅和锌的品位数据,实时判断工况变化和变化趋势,同时,计算当前品位与目标品位累计偏差,选择不同的浮选优化控制策略。最后,设计一套浮选优化控制策略,基于在线分析数据及目标控制值,并结合泡沫特征观测,实现浮选过程工况识别和优化决策,直接用于指导生产操作。工业生产实践表明,优化方法投入使用后铅、锌精矿回收率都有所提高,铅精矿、锌精矿中金和银的回收率提升最为显著,大幅度提高了选厂浮选生产技术指标和经济指标。研究结果可为同类多金属铅锌选矿生产提供了一种新的技术优化思路和方法,也为投用浮选智能优化自动控制提供了基础数据。 展开更多
关键词 铅锌矿选矿 X荧光品位分析 在线品位数据 浮选优化控制
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A land use regression for predicting NO_2 and PM_(10) concentrations in different seasons in Tianjin region,China 被引量:12
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作者 Li Chen Zhipeng Bai +5 位作者 Shaofei Kong Bin Han yan you Xiao Ding Shiyong Du Aixia Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第9期1364-1373,共10页
Land use regression (LUR) model was employed to predict the spatial concentration distribution of NO2 and PM10 in the Tianjin region based on the environmental air quality monitoring data. Four multiple linear regre... Land use regression (LUR) model was employed to predict the spatial concentration distribution of NO2 and PM10 in the Tianjin region based on the environmental air quality monitoring data. Four multiple linear regression (MLR) equations were established based on the most significant variables for NO2 in heating season (R2 = 0.74), and non-heating season (R2 = 0.61) in the whole study area; and PM10 in heating season (R2 = 0.72), and non-heating season (R2 = 0.49). Maps of spatial concentration distribution for NO2 and PM10 were obtained based on the MLR equations (resolution is 10 krn). Intercepts of MLR equations were 0.050 (NOz, heating season), 0.035 (NO2, non-heating season), 0.068 (PM10, heating season), and 0.092 (PM10, non-beating season) in the whole study area. In the central area of Tianjin region, the intercepts were 0.042 (NO2, heating season), 0.043 (NO2, non-heating season), 0.087 (PM10, heating season), and 0.096 (PMl0, non-heating season). These intercept values might imply an area's background concentrations. Predicted result derived from LUR model in the central area was better than that in the whole study area. Rz values increased 0.09 (heating season) and 0.18 (non-heating season) for NO2, and 0.08 (heating season) and 0.04 (non-heating season) for PMl0. In terms of R2, LUR model performed more effectively in heating season than non-heating season in the study area and gave a better result for NOz compared with PM10. 展开更多
关键词 land use regression air pollution TIANJIN background concentration geographic information system
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Application of land use regression for estimating concentrations of major outdoor air pollutants in Jinan, China 被引量:9
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作者 Li CHEN Shi-yong DU +5 位作者 Zhi-peng BAI Shao-fei KONG yan you Bin HAN Dao-wen HAN Zhi-yong LI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第11期857-867,共11页
SO2, NO2, and PM10 are the major outdoor air pollutants in China, and most of the cities in China have regulatory monitoring sites for these three air pollutants. In this study, we developed a land use regression (LUR... SO2, NO2, and PM10 are the major outdoor air pollutants in China, and most of the cities in China have regulatory monitoring sites for these three air pollutants. In this study, we developed a land use regression (LUR) model using regulatory monitoring data to predict the spatial distribution of air pollutant concentrations in Jinan, China. Traffic, land use and census data, and meteorological and physical conditions were included as candidate independent variables, and were tabulated for buffers of varying radii. SO2, NO2, and PM10 concentrations were most highly correlated with the area of industrial land within a buffer of 0.5 km (R2=0.34), the distance from an expressway (R2=0.45), and the area of residential land within a buffer of 1.5 km (R2=0.25), respectively. Three multiple linear regression (MLR) equations were established based on the most significant variables (p<0.05) for SO2, NO2, and PM10, and R2 values obtained were 0.617, 0.640, and 0.600, respectively. An LUR model can be applied to an area with complex terrain. The buffer radii of independent variables for SO2, NO2, and PM10 were chosen to be 0.5, 2, and 1.5 km, respectively based on univariate models. Intercepts of MLR equations can reflect the background concentrations in a certain area, but in this study the intercept values seemed to be higher than background concentrations. Most of the cities in China have a network of regulatory monitoring sites. However, the number of sites has been limited by the level of financial support available. The results of this study could be helpful in promoting the application of LUR models for monitoring pollutants in Chinese cities. 展开更多
关键词 Land use regression (LUR) Air pollution Background concentration Geographic information system (GIS)
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Decoding Cortical Glial Cell Development 被引量:6
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作者 Xiaosu Li Guoping Liu +15 位作者 Lin yang Zhenmeiyu Li Zhuangzhi Zhang Zhejun Xu Yuqun Cai Heng Du Zihao Su Ziwu Wang yangyang Duan Haotian Chen Zicong Shang yan you Qi Zhang Miao He Bin Chen Zhengang yang 《Neuroscience Bulletin》 SCIE CAS CSCD 2021年第4期440-460,共21页
Mouse cortical radial glial cells(RGCs)are primary neural stem cells that give rise to cortical oligodendrocytes,astrocytes,and olfactory bulb(OB)GABAergic interneurons in late embryogenesis.There are fundamental gaps... Mouse cortical radial glial cells(RGCs)are primary neural stem cells that give rise to cortical oligodendrocytes,astrocytes,and olfactory bulb(OB)GABAergic interneurons in late embryogenesis.There are fundamental gaps in understanding how these diverse cell subtypes are generated.Here,by combining single-cell RNA-Seq with intersectional lineage analyses,we show that beginning at around E16.5,neocortical RGCs start to generate ASCL1^(+)EGFR^(+)apical multipotent intermediate progenitors(MIPCs),which then differentiate into basal MIPCs that express ASCL1,EGFR,OLIG2,and MKI67.These basal MIPCs undergo several rounds of divisions to generate most of the cortical oligodendrocytes and astrocytes and a subpopulation of OB interneurons.Finally,single-cell ATAC-Seq supported our model for the genetic logic underlying the specification and differentiation of cortical glial cells and OB interneurons.Taken together,this work reveals the process of cortical radial glial cell lineage progression and the developmental origins of cortical astrocytes and oligodendrocytes. 展开更多
关键词 Radial glial cell Intermediate progenitor cell ASCL1 EGFR OLIG2 OLIGODENDROCYTE ASTROCYTE Olfactory bulb interneuron Cerebral cortex
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基于能质流平衡与数值仿真的浮渣转炉热工诊断与节能分析
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作者 闫友 谢环宇 +4 位作者 胡卫文 阳自霖 刘勇 闫红杰 刘柳 《有色金属(冶炼部分)》 CAS 北大核心 2024年第8期20-29,共10页
通过对铜浮渣转炉进行热工综合测试,获取了转炉关键位置的温度、压力、烟气组分等炉况参数,分析了转炉能量利用状况和能质流路径。通过数值模拟技术,基于热工测试数据,模拟了炉膛内天然气的富氧燃烧过程。结果表明,铜浮渣转炉的热效率为... 通过对铜浮渣转炉进行热工综合测试,获取了转炉关键位置的温度、压力、烟气组分等炉况参数,分析了转炉能量利用状况和能质流路径。通过数值模拟技术,基于热工测试数据,模拟了炉膛内天然气的富氧燃烧过程。结果表明,铜浮渣转炉的热效率为19.96%,转炉漏风量过大、壁面散热量过大是转炉热效率较低的主要原因。此外,转炉粒煤用量在反应热理论计算中过量较多。根据热工诊断结果,提出的节能优化建议为:调整粒煤用量,达成最优配料;采取保温措施,减少表面散热;增强转炉密闭性,减少漏风量;调整烧嘴布置方式,强化烟气与熔体换热。 展开更多
关键词 铜浮渣转炉 热工测试 热平衡 节能优化 数值模拟 天然气 富氧燃烧
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Assessing Liver Function by T1 Maps on Gd-EOB-DTPA- Enhanced MRI for up to 50 Min in Rat Models of Liver Fibrosis: A Longer Hepatobiliary Time Period may Help 被引量:3
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作者 Jia Xu Xuan Wang +5 位作者 Zhengyu Jin Qin Wang yan you Shitian Wang Tianyi Qian Huadan Xue 《Chinese Medical Sciences Journal》 CAS CSCD 2021年第2期110-119,共10页
Objectives To investigate whether a longer time period of gadolinium ethoxybenzyl diethylenetriaminepen-taacetic add(Gd-EOB-DTPA)-enhanced T1 mapping scanning,as well as dynamic contrast-enhanced(DCE)and multiple hepa... Objectives To investigate whether a longer time period of gadolinium ethoxybenzyl diethylenetriaminepen-taacetic add(Gd-EOB-DTPA)-enhanced T1 mapping scanning,as well as dynamic contrast-enhanced(DCE)and multiple hepatobiliary phase magnetic resonance imaging(MRI)have the potential to provide information about liver function in rats with liver fibrosis.Methods Forty rats were divided into the carbon tetrachloride-induced hepatic injury groups[carbon tetrachloride for four(n=14),eight(n=8),or twelve(n=8)weeks]and the control group(n=10).Gd-EOB-DTPA-enhanced MRI was performed including T1-mapping(delayed to 50 min),DCE,and multiple hepatobiliary phases.Indocyanine green retention rate at 15 min(ICG-R15)was determined.Parameters such as T1 reduction rate(△T1),elimination half-life of △T1(T_(△T1 1/2)),relative enhancement(RE),time to maximum RE(T_(max)),and perfusion parameters were calculated.Pearson correlation analysis was used for correlation analysis between ICG-R15 and each MRI indices.Results △T1 at 30,40,and 50 min showed significant positive correlations with ICG-R15(r=0.784,0.653,0.757,P=0.007,0.041,0.030).T_(△T1 1/2) showed a significant positive correlation with ICG-R15(r=0.685,P=0.029).showed a significant positive correlation with ICG-R15(r=0.532,P=0.019).Conclusions △T1 in the late hepatobiliary phase and T_(△T1 1/2) exhibited moderate correlations with liver function.The longer time period of Gd-EOB-DTPA-enhanced Tl mapping scanning,as well as DCE and multiple hepatobiliary phases,may be of some value for estimating liver function in rats with liver fibrosis. 展开更多
关键词 liver function T1 mapping GD-EOB-DTPA magnetic resonance imaging
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Measurement of air exchange rates in different indoor environments using continuous CO_2 sensors 被引量:2
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作者 yan you Can Niu +5 位作者 Jian Zhou Yating Liu Zhipeng Bai Jiefeng Zhang Fei He Nan Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第4期657-664,共8页
A new air exchange rate (AER) monitoring method using continuous CO2 sensors was developed and validated through both laboratory experiments and field studies. Controlled laboratory simulation tests were conducted i... A new air exchange rate (AER) monitoring method using continuous CO2 sensors was developed and validated through both laboratory experiments and field studies. Controlled laboratory simulation tests were conducted in a 1-m3 environmental chamber at different AERs (0.1-10.0 hr-1). AERs were determined using the decay method based on box model assumptions. Field tests were conducted in classrooms, dormitories, meeting rooms and apartments during 2-5 weekdays using CO2 sensors coupled with data loggers. Indoor temperature, relative humidity (RH), and CO2 concentrations were continuously monitored while outdoor parameters combined with on-site climate conditions were recorded. Statistical results indicated that good laboratory performance was achieved: duplicate precision was within 10%, and the measured AERs were 90%-120% of the real AERs. Average AERs were 1.22, 1.37, 1.10, 1.91 and 0.73 hr-l in dormitories, air-conditioned classrooms, classrooms with an air circulation cooling system, reading rooms, and meeting rooms, respectively. In an elderly particulate matter exposure study, all the homes had AER values ranging from 0.29 to 3.46 hr-1 in fall, and 0.12 to 1.39 hr-1 in winter with a median AER of 1.15. 展开更多
关键词 air exchange rate continuous CO2 sensor steady-state method decay method particulate matter indoor-outdoorconcentration relationship
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粗铅冶炼过程中砷镉铊的走向分布及治理措施 被引量:3
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作者 胡卫文 陈坤 +4 位作者 阳自霖 闫友 申群友 唐志波 李懋 《中国有色冶金》 CAS 北大核心 2024年第2期147-155,共9页
在粗铅冶炼工艺中,铅精矿和其他含铅物料中的砷、镉、铊分布于各工序环节,不利于有价金属资源的回收,而且加大了冶炼废弃物的处理难度,另外还对人体健康和环境造成负面影响。现有文献对于砷、镉、铊在粗铅冶炼过程中的分布及趋向还未见... 在粗铅冶炼工艺中,铅精矿和其他含铅物料中的砷、镉、铊分布于各工序环节,不利于有价金属资源的回收,而且加大了冶炼废弃物的处理难度,另外还对人体健康和环境造成负面影响。现有文献对于砷、镉、铊在粗铅冶炼过程中的分布及趋向还未见报道,本文根据某冶炼企业实际生产情况,统计了2021年及2022年分别为期14d的两套物料平衡数据,对砷、镉、铊在各冶炼工序的分布进行了分析,得到以下结论。砷的分布情况:在底吹炉工序中,约85%砷进入高铅渣,约9%砷进入烟灰,约6%砷进入硫酸净化污酸系统;在还原炉工序,约70%以上砷形成铅铜锍进入粗铅,约20%砷进入还原炉烟灰,10%以下的砷通过还原渣进入烟化炉。镉、铊的分布情况:高度富集于底吹炉和侧吹炉烟灰中,其中底吹炉烟灰中富集比例为85%~95%,只有5%~15%进入高铅渣转至还原炉工序,极少部分进入硫酸系统。企业采用开路底吹炉烟尘方式减少粗铅冶炼系统中砷、镉、铊的含量,开路标准是烟尘含镉超过20%时从收尘系统开路,当烟尘含镉低于15%停止开路,取出的烟尘可直接作为回收镉的原料外售。本文分析结果及解决方法可为同类企业控制冶炼系统中砷镉铊的分布提供参考。 展开更多
关键词 粗铅冶炼 砷、镉、铊 烟尘开路 有害元素分布 资源回收
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降低铅冶炼底吹炉高铅渣含硫量的生产实践 被引量:1
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作者 闫友 付高明 +1 位作者 胡卫文 阳自霖 《绿色矿冶》 2024年第1期34-39,共6页
某铅冶炼厂采用“富氧底吹氧化-氧气侧吹还原”工艺进行粗铅冶炼,底吹炉产出的高铅渣含硫量较高,达到1.3%~1.6%,对后续尾气脱硫系统造成一定影响,环保处理成本升高。为了解决该问题,本文结合理论和生产实践分析了铅冶炼底吹炉高铅渣含... 某铅冶炼厂采用“富氧底吹氧化-氧气侧吹还原”工艺进行粗铅冶炼,底吹炉产出的高铅渣含硫量较高,达到1.3%~1.6%,对后续尾气脱硫系统造成一定影响,环保处理成本升高。为了解决该问题,本文结合理论和生产实践分析了铅冶炼底吹炉高铅渣含硫高的主要原因。高铅渣中的硫主要以硫酸根形态存在,这些硫酸根一部分来自入炉物料中的硫酸盐类铅物料,另一部分则是在熔炼过程中由硫化铅精矿发生氧化反应生成的。降低高铅渣含硫量的主要途径是提高熔池熔炼的温度和降低系统中SO_(2)的分压。结合生产实践从渣型、氧料比、入炉粒矿含硫、系统SO_(2)分压等方面探讨了降低底吹炉高铅渣含硫量的途径和方法。在含铅渣料搭配比例30%左右,控制渣温1050~1100℃,控制渣型FeO/SiO_(2)1.4~1.8,CaO/SiO_(2)0.4~0.6;氧料比100~110 Nm^(3)/t,入炉粒矿有效硫12.5%~13.5%及适当负压等相关工艺参数组合条件下,可使高铅渣残硫保持在1.2%以下。 展开更多
关键词 铅冶炼 底吹炉 高铅渣 渣含硫量
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Sclerosing epithelioid fibrosarcoma of the pancreas:A case report 被引量:1
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作者 Meng-Qing Sun Li-Na Guo +3 位作者 yan you yan-Yu Qiu Xiao-Dong He Xian-Lin Han 《World Journal of Clinical Cases》 SCIE 2024年第26期5983-5989,共7页
BACKGROUND A sclerosing epithelioid fibrosarcoma(SEF)is a rare malignant fibroblastic soft tissue tumor that rarely occurs in intra-abdominal organs.A case of a SEF in the pancreatic head is reported herein,including ... BACKGROUND A sclerosing epithelioid fibrosarcoma(SEF)is a rare malignant fibroblastic soft tissue tumor that rarely occurs in intra-abdominal organs.A case of a SEF in the pancreatic head is reported herein,including its clinical manifestations,preoperative imaging features,gross specimen and pathological findings.CASE SUMMARY A 33-year-old male patient was admitted to Peking Union Medical College Hospital in December 2023 due to a one-year history of intermittent upper abdominal pain and the discovery of a pancreatic mass.The patient underwent an enhanced computed tomography scan of the abdomen,which revealed a welldefined,round mass with clear borders and calcifications in the pancreatic head.The mass exhibited progressive,uneven mild enhancement,measuring approximately 6.6 cm×6.3 cm.The patient underwent laparoscopic pylorus-preserving pancreaticoduodenectomy.Postoperative pathological examination revealed that the lesion was consistent with a SEF.At the 3-month postoperative follow-up,the patient did not report any short-term complications,and there were no signs of tumor recurrence.CONCLUSION SEFs are rare malignant fibrous soft tissue tumors.SEFs rarely develop in the pancreas,and its preoperative diagnosis depends on imaging findings,with confirmation depending on pathological examination and immunohistochemistry.Currently,only four cases of pancreatic SEF have been reported in studies written in English.This case is the first reported case of a pancreatic SEF by a clinical physician. 展开更多
关键词 Sclerosing epithelioid fibrosarcoma of the pancreas Abdominal malignant fibroblastic soft tissue tumor Abdominal enhanced computed tomography Laparoscopic pancreaticoduodenectomy Case report
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高铊污酸综合处理工艺及工业实践
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作者 闫友 陈国兰 +1 位作者 胡卫文 阳自霖 《中国有色冶金》 CAS 北大核心 2023年第6期148-157,共10页
铅锌冶炼易产生高酸、高卤素、高铊的污酸,采用常规处理方法需要消耗大量的石灰和硫化钠,产生危废量大,后续难以处理。本文提出“氧化-树脂吸附-分段中和”工艺处理高铊污酸,并基于该方法考察了不同氧化剂及吸附形式对树脂吸附铊的影响... 铅锌冶炼易产生高酸、高卤素、高铊的污酸,采用常规处理方法需要消耗大量的石灰和硫化钠,产生危废量大,后续难以处理。本文提出“氧化-树脂吸附-分段中和”工艺处理高铊污酸,并基于该方法考察了不同氧化剂及吸附形式对树脂吸附铊的影响,并进行了工业验证,得到以下结论:氧化阶段,高锰酸钾效果最好,考虑到成本,工业生产采用双氧水进行氧化;动态吸附优于静态吸附,且动态吸附处理污酸具有连续性,有利于工业应用;试验所用阴离子交换树脂对三价铊的吸附效果良好,动态平均吸附效率为89.07%,对镉具有吸附效果,动态平均吸附效率为50.66%,对铅、锌、砷元素不具有吸附性;该工艺处理后的污酸后液中铊、砷含量均能稳定达到5μg/L、0.3 mg/L的排放标准,分段中和产生的石膏渣、中和渣中铊含量低于20 g/t,不被定性为含铊污泥。该方法不但能富集铊元素,还能改善石膏渣的品质,有利于对石膏渣的资源利用,实现含铊污泥的减量化,另外吸附后树脂可以再生循环利用,节约污酸处理成本,具有在铅锌工业高卤素污酸废水处理领域的推广价值。 展开更多
关键词 铅锌冶炼 污酸 重金属脱除 铊脱除 树脂吸附 铊污泥 资源利用
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轮内电动汽车直接横摆力矩控制
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作者 严友 李美 《微特电机》 2019年第1期55-58,共4页
针对参数变化及不确定性干扰等非线性因素对于车辆稳定性的影响,设计出一种基于自适应鲁棒滑模控制的策略,保证轮内电动汽车在上述不确定因素的干扰下,仍然可以保证车辆的行驶稳定性。具体搭建了整车二自由度模型和驱动电动机模型,设计... 针对参数变化及不确定性干扰等非线性因素对于车辆稳定性的影响,设计出一种基于自适应鲁棒滑模控制的策略,保证轮内电动汽车在上述不确定因素的干扰下,仍然可以保证车辆的行驶稳定性。具体搭建了整车二自由度模型和驱动电动机模型,设计自适应鲁棒滑模控制律,利用先进车辆动力学仿真软件Carsim对该控制策略进行了仿真实验;同时进行了实车试验。试验和仿真结果表明,该算法可有效实现直接横摆力矩控制,使车辆在有较大侧向风的干扰下保持行驶稳定性。 展开更多
关键词 轮内电动汽车 直接横摆力矩控制 自适应鲁棒滑模 行驶稳定性
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Exposure measurement, risk assessment and source identification for exposure of traffic assistants to particle-bound PAHs in Tianjin, China 被引量:2
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作者 Xiaodan Xue yan you +4 位作者 Jianhui Wu Bin Han Zhipeng Bai Naijun Tang Liwen Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第2期448-457,共10页
To investigate the levels of exposure to particulate-bound polycyclic aromatic hydrocarbon (PAH) and to estimate the risk these levels pose to traffic assistants (TAs) in Tianjin (a rnegacity in North China), a ... To investigate the levels of exposure to particulate-bound polycyclic aromatic hydrocarbon (PAH) and to estimate the risk these levels pose to traffic assistants (TAs) in Tianjin (a rnegacity in North China), a measurement campaign (33 all-day exposure samples, 25 occupational-exposure samples and 10 indoor samples) was conducted to characterize the TAs' exposure to PAHs, assess the cancer risk and identify the potential sources of exposure. The average total exposure concentration of 14 PAHs was approximately 2871 + 928 ng/rn3 (on-duty), and 1622 + 457 ng/m3 (all-day). The indoor PAHs level was 1257 + 107 ng/m3. After 8000 Monte Carlo simulations, the cancer risk resulting from exposure to PAHs was found to be approximately 1.05 x 10-4. A multivariate analysis was applied to identify the potential sources, and the results showed that, in addition to vehicle exhaust, coal combustion and cooking fumes were also another two important contributors to personal PAH exposure. The diagnostic ratios of PAH compounds agree with the source apportionment results derived from principal component analysis. 展开更多
关键词 polycyclic aromatic hydrocarbons exposure risk assessment traffic assistants source identification
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