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Elucidating the cardioprotective mechanisms of sodium-glucose cotransporter-2 inhibitors beyond glycemic control
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作者 Ke-Xin Zhang Cheng-Xia Kan +2 位作者 fang han Jing-Wen Zhang Xiao-Dong Sun 《World Journal of Diabetes》 SCIE 2024年第2期137-141,共5页
Sodium-glucose cotransporter-2(SGLT2)inhibitors have emerged as a pivotal intervention in diabetes management,offering significant cardiovascular benefits.Empagliflozin,in particular,has demonstrated cardioprotective ... Sodium-glucose cotransporter-2(SGLT2)inhibitors have emerged as a pivotal intervention in diabetes management,offering significant cardiovascular benefits.Empagliflozin,in particular,has demonstrated cardioprotective effects beyond its glucose-lowering action,reducing heart failure hospitalizations and improving cardiac function.Of note,the cardioprotective mechanisms appear to be independent of glucose lowering,possibly mediated through several mechanisms involving shifts in cardiac metabolism and anti-fibrotic,anti-inflammatory,and anti-oxidative pathways.This editorial summarizes the multifaceted cardiovascular advantages of SGLT2 inhibitors,highlighting the need for further research to elucidate their full therapeutic potential in cardiac care. 展开更多
关键词 DIABETES Sodium-glucose cotransporter-2 Cardiovascular diseases Empagliflozin
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Evolution of deformation mechanisms and their orientation dependence in fine-grained Mg-3Gd during tension
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作者 Faping Hu Tianbo Yu +5 位作者 Hao Chen fang han Keshun Dai fangcheng Qiu Weidong Xie Xiaoxu Huang 《Journal of Magnesium and Alloys》 CSCD 2024年第12期5095-5107,共13页
Magnesium alloys usually exhibit poor ductility attributed to their intrinsic hexagonal close-packed(hcp)structure,which fails to provide sufficient independent slip systems for homogeneous deformation.Here we demonst... Magnesium alloys usually exhibit poor ductility attributed to their intrinsic hexagonal close-packed(hcp)structure,which fails to provide sufficient independent slip systems for homogeneous deformation.Here we demonstrate that multiple deformation mechanisms can be activated with increasing tensile strain in a fine-grained Mg-3Gd with a weak basal texture.<c+a>slip,tension twinning and compression/double twinning exhibit a high orientation dependence at an early stage of deformation,whereas the orientation dependence becomes less obvious with further increasing strain.The high work hardening rate at the strain of 2%–5%is accompanied by the significant increase of<c+a>slip and tension twinning activities.The fine microstructure strongly restricts the activation and growth of twinning,resulting in a slow exhaust of tension twinning and thin compression twins.The restriction of twinning and the activation of profuse<c+a>slip near grain/twin boundaries,relaxing the stress concentration,sustain the homogeneous deformation to a high strain. 展开更多
关键词 Fine-grained Mg alloy Deformation mechanisms Orientation dependence Mechanical property
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城市地下综合体空间效能评价体系构建及实证研究 被引量:1
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作者 方翰 沈中伟 +2 位作者 喻冰洁 彭迎澳 韩磊 《新建筑》 2025年第1期122-127,共6页
在城市轨道交通快速发展、存量土地再开发的背景下,城市平面延伸广度及竖向建设深度均有所拓展,更表现出空间组织立体多变、建筑功能叠加交织的特征。地下综合体成为实现城市空间高效运转的新基面与驱动点,其空间效能的发挥对城市可持... 在城市轨道交通快速发展、存量土地再开发的背景下,城市平面延伸广度及竖向建设深度均有所拓展,更表现出空间组织立体多变、建筑功能叠加交织的特征。地下综合体成为实现城市空间高效运转的新基面与驱动点,其空间效能的发挥对城市可持续、高品质发展具有重要意义。文章梳理了地下空间研究脉络,构建了城市地下综合体效能评价体系;基于多源时空大数据,对国内典型城市地下综合体的空间效能进行系统测度,通过聚类分析法,识别了地下综合体的空间效能主导类型。研究旨在为城市立体空间一体化发展的探索、为城市地下空间领域理论和实践提供支撑。 展开更多
关键词 地下综合体 空间效能 评价模型 空间一体化 立体城市 研究进展 主导类型
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基于PI3K/AKT信号通路探讨GNB4对结直肠癌细胞生物学行为的影响
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作者 林潇 陈灵斌 +4 位作者 刘炳辉 陈慧 方涵 潘菊花 游淑清 《温州医科大学学报》 2025年第10期789-796,共8页
目的:分析结直肠癌(CRC)中鸟嘌呤核苷酸结合蛋白亚单位β4(GNB4)表达水平及其对临床预后的影响,探讨GNB4在CRC细胞恶性生物学行为中的作用及其分子机制。方法:从GEO数据库下载CRC的转录数据,收集2016年2月至2017年2月台州市第一人民医... 目的:分析结直肠癌(CRC)中鸟嘌呤核苷酸结合蛋白亚单位β4(GNB4)表达水平及其对临床预后的影响,探讨GNB4在CRC细胞恶性生物学行为中的作用及其分子机制。方法:从GEO数据库下载CRC的转录数据,收集2016年2月至2017年2月台州市第一人民医院收治的100例CRC患者,研究GNB4在CRC癌组织和正常组织中的表达差异;利用Kaplan-Meier分析GNB4表达与CRC患者总生存期的关系。采用RT-q PCR和免疫组化方法验证CRC组织及其癌旁组织中GNB4的表达水平及与患者总生存期的相关性。以CRC细胞系DLD-1为实验对象,采用CCK-8增殖实验、Transwell侵袭实验和划痕愈合实验、Western blot探讨GNB4对CRC细胞增殖、侵袭、转移生物学行为及PI3K/AKT信号通路的影响。利用P13K/AKT通路激活剂740Y-P处理GNB4敲低细胞系并检测细胞生物学行为的变化。结果:GNB4 mRNA在GEO数据集、本中心的CRC组织的相对表达量均高于癌旁正常组织(P<0.05)。生存分析结果显示,GNB4高表达与CRC患者的总生存期及无远处转移生存率密切相关(P<0.05);多因素回归分析表明GNB4(HR=5.013,95%CI=1.556~16.152,P=0.007)是CRC患者独立的预后因素。敲低GNB4的表达能明显抑制CRC细胞株DLD-1的增殖、侵袭、迁移(P<0.05);与空白对照组相比,si-GNB4组细胞中p-PI3K/PI3K、p-AKT/AKT的比值明显降低(P<0.05),而P13K/AKT通路激活剂740Y-P能逆转敲低GNB4对细胞的作用(P<0.05)。结论:GNB4可以通过PI3K/AKT信号通路促进DLD-1细胞迁移与侵袭,进而影响CRC患者的预后。 展开更多
关键词 鸟嘌呤核苷酸结合蛋白亚单位β4 结直肠癌 PI3K/AKT
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松辽流域动态监测数据处理软件设计与实践
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作者 李丹 张延玲 +4 位作者 房含 王迪晨 祁泓锟 王鹭 高海宁 《水利科学与寒区工程》 2025年第9期129-133,共5页
为提高松辽流域水土流失动态监测数据处理效率,在梳理土壤侵蚀因子、因子计算方法、数据质量控制、成果数据统计分析要求的基础上,设计开发了松辽流域水土流失动态监测数据处理软件,实现了数据质量检查、土壤侵蚀计算、区域数据处理、... 为提高松辽流域水土流失动态监测数据处理效率,在梳理土壤侵蚀因子、因子计算方法、数据质量控制、成果数据统计分析要求的基础上,设计开发了松辽流域水土流失动态监测数据处理软件,实现了数据质量检查、土壤侵蚀计算、区域数据处理、成果统计等功能。该软件连续4年应用于松辽流域水土流失动态监测工作,支撑完成了松辽流域每年约88万km^(2)区域的数据计算与统计工作。显著提高了数据质量检查、栅格数据计算、区域数据处理及成果统计工作效率和质量。 展开更多
关键词 松辽流域 动态监测 数据处理 软件设计
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跨越时空的爱恋-——爱伦·坡悼亡诗中的怀旧建构
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作者 方涵 戚涛 《徐州工程学院学报(社会科学版)》 2025年第2期52-59,共8页
爱伦·坡是美国文学史上极具影响力的人物,其作品引发各界的一再解读,但其诗歌中的怀旧建构鲜有人知。借用怀旧认知图示理论,研究探究了爱伦·坡诗歌中的怀旧建构。现代性情境下的变革疏离、稳定可靠情感纽带的缺乏推动爱伦... 爱伦·坡是美国文学史上极具影响力的人物,其作品引发各界的一再解读,但其诗歌中的怀旧建构鲜有人知。借用怀旧认知图示理论,研究探究了爱伦·坡诗歌中的怀旧建构。现代性情境下的变革疏离、稳定可靠情感纽带的缺乏推动爱伦·坡怀旧情结的产生;通过怀旧,爱伦·坡在诗歌中建构了理想时空、分离式恋情、怀旧自我等要素,以弥补现实中安全感和归属感的缺失。这些建构在一定程度上缓解了爱伦·坡的自我认同危机,然而因其处境欠佳、与现实博弈的能力有限,且建构的理性化空间和情感纽带距离现实太过遥远,爱伦·坡怀旧建构呈现低效性。 展开更多
关键词 爱伦·坡 爱情 怀旧 时空
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不同BMI分级对全膝关节置换术后康复效果及并发症的回顾性分析
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作者 章镇南 钱晓晋 +2 位作者 彭仁亮 方晗 倪晨波 《现代生物医学进展》 2025年第11期1806-1813,1778,共9页
目的:探讨不同BMI分级对全膝关节置换术(TKA)术后康复效果及并发症的影响。方法:回顾性分析2022年1月至2024年6月在我院接受TKA治疗的88例患者临床资料,根据世界卫生组织(WHO)BMI标准将患者分为正常体重组(18.5≤BMI<24.9 kg/m^(2))... 目的:探讨不同BMI分级对全膝关节置换术(TKA)术后康复效果及并发症的影响。方法:回顾性分析2022年1月至2024年6月在我院接受TKA治疗的88例患者临床资料,根据世界卫生组织(WHO)BMI标准将患者分为正常体重组(18.5≤BMI<24.9 kg/m^(2))、超重组(25.0≤BMI<29.9 kg/m^(2))、轻度肥胖组(30.0≤BMI<34.9 kg/m^(2))及重度肥胖组(BMI≥35.0 kg/m^(2))。比较各组术前基线资料、手术时间、术中出血量、住院时间、术后膝关节功能评分、疼痛评分、关节活动度(Range of Motion,ROM)及并发症发生率等指标。结果:随着BMI值增加,患者手术时间延长,术中出血量增加,住院时间延长,差异具有统计学意义(P<0.05)。术后3个月及6个月随访时,膝关节学会评分(KSS)及西安大略与麦克马斯特大学关节炎指数(WOMAC)评分显示,随BMI增加,功能恢复程度降低(P<0.05)。术后并发症方面,肥胖组切口愈合不良、感染、深静脉血栓(Deep Vein Thrombosis,DVT)发生率明显高于正常体重组和超重组(P<0.05)。结论:BMI是影响TKA术后康复效果及并发症发生的重要因素。高BMI患者术后功能恢复较慢,并发症发生率较高。针对高BMI患者,应考虑术前减重及制定个体化康复方案,以改善TKA术后预后。 展开更多
关键词 体质指数 全膝关节置换术 康复效果 并发症 回顾性分析
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A spinal circuit model with an asymmetric cervical-lumbar layout for limb coordination and gait control in quadrupeds
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作者 Qinghua ZHU fang han Qingyun WANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第8期1433-1450,I0006-I0009,共22页
In quadrupeds,the cervical and lumbar circuits work together to achieve the speed-dependent gait expression.While most studies have focused on how local lumbar circuits regulate limb coordination and gaits,relatively ... In quadrupeds,the cervical and lumbar circuits work together to achieve the speed-dependent gait expression.While most studies have focused on how local lumbar circuits regulate limb coordination and gaits,relatively few studies are known about cervical circuits and even less about locomotor gaits.We use the previously published models by Danner et al.(DANNER,S.M.,SHEVTSOVA,N.A.,FRIGON,A.,and RYBAK,I.A.Computational modeling of spinal circuits controlling limb coordination and gaits in quadrupeds.e Life,6,e31050(2017))as a basis,and modify it by proposing an asymmetric organization of cervical and lumbar circuits.First,the model reproduces the typical speed-dependent gait expression in mice and more biologically appropriate locomotor parameters,including the gallop gait,locomotor frequencies,and limb coordination of the forelimbs.Then,the model replicates the locomotor features regulated by the M-current.The walk frequency increases with the M-current without affecting the interlimb coordination or gaits.Furthermore,the model reveals the interaction mechanism between the brainstem drive and ionic currents in regulating quadrupedal locomotion.Finally,the model demonstrates the dynamical properties of locomotor gaits.Trot and bound are identified as attractor gaits,walk as a semi-attractor gait,and gallop as a transitional gait,with predictable transitions between these gaits.The model suggests that cervical-lumbar circuits are asymmetrically recruited during quadrupedal locomotion,thereby providing new insights into the neural control of speed-dependent gait expression. 展开更多
关键词 locomotor control cervical-lumbar asymmetrical spinal circuit computational modeling ionic current GAIT
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关于松辽流域国家级水土流失动态监测工作阶段经验的探讨
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作者 李丹 房含 +2 位作者 王迪晨 常诚 高海宁 《黑龙江水利科技》 2025年第3期147-151,共5页
2018—2022年,松辽水利委员会完成松辽流域6个国家级重点防治区水土流失动态监测工作,年度监测面积约88.77万km^(2),涉及167个县(市、区、旗)。文章从技术流程与方法、项目完成情况、主要成果与成效、主要经验与做法、主要结论5个主要... 2018—2022年,松辽水利委员会完成松辽流域6个国家级重点防治区水土流失动态监测工作,年度监测面积约88.77万km^(2),涉及167个县(市、区、旗)。文章从技术流程与方法、项目完成情况、主要成果与成效、主要经验与做法、主要结论5个主要方面对五年间松辽流域国家级重点防治区水土流失监测工作进行了系统总结,为后续项目开展提供重要参考。 展开更多
关键词 松辽流域 水土流失 水土保持 动态监测
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Effects of climate change on phenology and primary productivity in the desert steppe of Inner Mongolia 被引量:8
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作者 fang han Qing ZhanG +7 位作者 Alexander BUYANTUEV Jian Ming NIU Peng Tao LIU Xing Hua LI Sarula KANG Jing ZhanG Chang Ming ChanG Yun Peng LI 《Journal of Arid Land》 SCIE CSCD 2015年第2期251-263,共13页
Variations in temperature and precipitation affect local ecosystems. Considerable spatial and temporal heterogeneity exists in arid ecosystems such as desert steppes. In this study, we analyzed the spatiotemporal dy- ... Variations in temperature and precipitation affect local ecosystems. Considerable spatial and temporal heterogeneity exists in arid ecosystems such as desert steppes. In this study, we analyzed the spatiotemporal dy- namics of climate and vegetation phenology in the desert steppe of Inner Mongolia, China using meteorological data (1961-2010) from 11 stations and phenology data (2004-2012) from 6 ecological observation stations. We also estimated the gross primary production for the period of 1982-2009 and found that the annual mean tem- perature increased at a rate of 0.47~C/decade during 1961-2010, with the last 10 years being consistently warmer than the 50 years as an average. The most significant warming occurred in winters. Annual precipitation slightly decreased during the 50-year period, with summer precipitation experiencing the highest drop in the last 10 years, and spring precipitation, a rise. Spatially, annual precipitation increased significantly in the northeastern and eastern central areas next to the typical steppe. From 2004 to 2012, vegetation green-up and senescence date advanced in the study area, shortening the growing season. Consequently, the primary productivity of the desert steppe de- creased along the precipitation gradient from southeast to northwest. Temporally, productivity increased during the period of 1982-1999 and significantly decreased after 2000. Overall, the Last decade witnessed the most dramatic climatic changes that were likely to negatively affect the desert steppe ecosystem. The decreased primary produc- tivity, in particular, decreases ecosystem resilience and impairs the livelihood of local farmers and herdsmen. 展开更多
关键词 desert steppe green-up gross primary productivity PHENOLOGY PRECIPITATION TEMPERATURE
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Differences in clinical and genetic characteristics between early-and late-onset narcolepsy in a Han Chinese cohort
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作者 Hui Ouyang fang han +1 位作者 Ze-Chen Zhou Jun Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第10期1887-1893,共7页
Early-and late-onset narcolepsy constitutes two distinct diagnostic subgroups.However,it is not clear whether symptomology and genetic risk factors differ between early-and late-onset narcoleptics.This study compared ... Early-and late-onset narcolepsy constitutes two distinct diagnostic subgroups.However,it is not clear whether symptomology and genetic risk factors differ between early-and late-onset narcoleptics.This study compared clinical data and single-nucleotide polymorphisms(SNPs)between early-and late-onset patients in a large cohort of 899 Han Chinese narcolepsy patients.Blood,cerebrospinal fluid,and clinical data were prospectively collected from patients,and patients were genotyped for 40 previously reported narcolepsy risk-conferring SNPs.Genetic risk scores(GRSs),associations of five different sets of SNPs(GRS1–GRS5)with early-and late-onset narcolepsy,were evaluated using logistic regression and receiver operating characteristic curves.Mean sleep latency was significantly shorter in early-onset cases than in late-onset cases.Symptom severity was greater among late-onset patients,with higher rates of sleep paralysis,hypnagogic hallucinations,health-related quality of life impairment,and concurrent presentation with four or more symptoms.Hypocretin levels did not differ significantly between early-and late-onset cases.Only rs3181077(CCR1/CCR3)and rs9274477(HLA-DQB1)were more prevalent among early-onset cases.Only GRS1(26 SNPs;OR=1.513,95%CI:0.893–2.585;P<0.05)and GRS5(6 SNPs;OR=1.893,95%CI:1.204–2.993;P<0.05)were associated with early-onset narcolepsy,with areas under the receiver operating characteristic curves of 0.731 and 0.732,respectively.Neither GRS1 nor GRS5 included SNPs in HLA regions.Our results indicate that symptomology and genetic risk factors differ between early-and late-onset narcolepsy.This protocol was approved by the Institutional Review Board(IRB)Panels on Medical Human Subjects at Peking University People’s Hospital,China(approval No.Yuanlunshenlinyi 86)in October 2011. 展开更多
关键词 case-control studies clinical features genetic association studies genetic load genetic loci genetic phenomena hypothalamic diseases precision medicine risk assessment single nucleotide polymorphism
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GANT61通过调控自噬诱导结肠癌细胞凋亡
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作者 张虹 张建国 +4 位作者 何苗 袁正 方涵 喻长法 夏青青 《胃肠病学》 2024年第12期744-749,共6页
背景:结直肠癌是消化系统常见恶性肿瘤且病死率高,探索新的治疗靶点对于提高进展期结直肠癌患者的生存率具有重要意义。目的:探讨Hedgehog信号通路核心转录因子GLI抑制剂GANT61是否系通过调控自噬诱导结肠癌细胞凋亡。方法:体外培养人... 背景:结直肠癌是消化系统常见恶性肿瘤且病死率高,探索新的治疗靶点对于提高进展期结直肠癌患者的生存率具有重要意义。目的:探讨Hedgehog信号通路核心转录因子GLI抑制剂GANT61是否系通过调控自噬诱导结肠癌细胞凋亡。方法:体外培养人结肠癌细胞株SW480,以不同浓度GANT61(0、10、20、40μmol/L)处理细胞24 h,以CCK-8实验检测细胞活力,流式细胞术检测细胞凋亡,qRT-PCR、蛋白质印迹法检测GLI1、GLI2以及细胞凋亡、自噬相关基因和(或)蛋白表达。通过联合自噬抑制剂氯喹或自噬激动剂雷帕霉素处理细胞验证自噬在GANT61诱导结肠癌细胞凋亡中的作用。结果:GANT61可浓度依赖性地抑制SW480细胞活力并诱导细胞凋亡;同时,GLI1、GLI2、G1/S期特异性细胞周期蛋白D1、抗凋亡蛋白BCL-2 mRNA和蛋白表达受抑,凋亡相关蛋白切割型聚腺苷二磷酸核糖聚合酶1(C-PARP1)和自噬相关蛋白Beclin1、LC3-Ⅱ表达增加。氯喹能部分逆转GANT61诱导的SW480细胞凋亡,雷帕霉素则能促进GANT61的诱导凋亡效应。结论:GANT61可能通过激活自噬诱导结肠癌细胞凋亡。自噬激动剂雷帕霉素联合GANT61可能为结直肠癌的治疗提供新的思路。 展开更多
关键词 HEDGEHOG信号通路 GANT61 结肠肿瘤 自噬 细胞凋亡
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碳量子点与半导体复合光催化材料合成及降解有机污染物的应用进展 被引量:3
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作者 周雨洁 赵斌 +6 位作者 沈谊豪 李秀明 郭小云 王昱童 高雅 方涵 王志有 《化工技术与开发》 CAS 2024年第3期41-49,共9页
有机污染物的危害日益严重,引起人们的广泛关注。半导体光催化降解有机污染物是公认的绿色技术,但传统的半导体光催化材料对可见光的利用率低,光生电子与空穴易复合,导致降解有机污染物的效率不高,开发高效、稳定的半导体复合光催化材料... 有机污染物的危害日益严重,引起人们的广泛关注。半导体光催化降解有机污染物是公认的绿色技术,但传统的半导体光催化材料对可见光的利用率低,光生电子与空穴易复合,导致降解有机污染物的效率不高,开发高效、稳定的半导体复合光催化材料,是当前光催化领域的研究热点。碳量子点(CQDs)是新型的纳米级荧光碳材料,可作为修饰剂与半导体材料复合,能够显著提高复合材料的光催化降解效率,极大地激发了研究者的兴趣。本文介绍了碳量子点与半导体光催化剂的复合方法,总结了近几年CQDs/半导体复合光催化材料降解有机染料、抗生素、止痛药、酚类化合物等有机污染物的应用成果。 展开更多
关键词 CQDs/半导体复合光催化材料 降解 有机染料 抗生素 止痛药 酚类化合物
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澜沧江云南吻孔鲃肌肉营养成分分析与评价 被引量:2
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作者 钟文武 周睿 +5 位作者 鲁祥兴 吴敬东 严燕群 方晗 袁溯 吴胜亮 《饲料研究》 CAS 北大核心 2024年第10期118-124,共7页
试验旨在探究人工繁殖饲养的云南吻孔鲃肌肉营养成分,测定了云南吻孔鲃肌肉常规营养成分、氨基酸组成、脂肪酸组成和矿质元素。结果表明,云南吻孔鲃肌肉(鲜样)中水分、粗蛋白、粗脂肪和灰分含量分别为78.05%、17.16%、2.22%和1.13%。云... 试验旨在探究人工繁殖饲养的云南吻孔鲃肌肉营养成分,测定了云南吻孔鲃肌肉常规营养成分、氨基酸组成、脂肪酸组成和矿质元素。结果表明,云南吻孔鲃肌肉(鲜样)中水分、粗蛋白、粗脂肪和灰分含量分别为78.05%、17.16%、2.22%和1.13%。云南吻孔鲃肌肉中共检出17种氨基酸,氨基酸总量为(13.98±0.30)%,必需氨基酸所占比例为(5.80±0.05)%,非必需氨基酸所占比例为(8.18±0.26)%,鲜味氨基酸所占比例为(5.28±0.33)%,必需氨基酸总量符合FAO/WHO推荐的理想蛋白标准,第一限制氨基酸为蛋氨酸+胱氨酸,必需氨基酸指数为75.77。云南吻孔鲃肌肉中共检出15种脂肪酸,总不饱和脂肪酸相对含量为64.13%,以C18系列为主,油酸含量最高,为(43.32±9.43)%。常量元素中,云南吻孔鲃肌肉钾(K)含量最高,为(3 516.00±82.73) mg/kg;镁(Mg)含量最低,为(319.04±15.58)mg/kg。微量元素中,云南吻孔鲃肌肉铁(Fe)的含量最高,为(18.35±6.28) mg/kg;锰(Mn)含量最低,为(0.12±0.02) mg/kg。研究表明,云南吻孔鲃是一种富含氨基酸、脂肪酸、矿质元素且营养均衡的膳食鱼类,其在作为高油酸膳食方面具有较高的开发和应用前景。 展开更多
关键词 云南吻孔鲃 肌肉 营养成分 分析评价
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Effect of initial grain size on the recrystallization behavior and recrystallization texture of a Mg-3Gd alloy 被引量:1
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作者 fang han Xuan Luo +3 位作者 Knut Marthinsen Guilin Wu Ziyong Hou Xiaoxu Huang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第21期169-182,共14页
The effect of initial grain size on the recrystallization and recrystallization texture of a rolled Mg–3Gd(wt.%)alloy is studied in detail.The results show that the deformation microstructure of an initially coarse-g... The effect of initial grain size on the recrystallization and recrystallization texture of a rolled Mg–3Gd(wt.%)alloy is studied in detail.The results show that the deformation microstructure of an initially coarse-grained(CG)sample has a larger twinned area and a higher density of twin boundaries than a fine-grained(FG)sample.After annealing,the CG sample recrystallizes preferentially in the twinned area,whereas the FG sample adopts the higher density grain boundaries as the nucleation sites.Furthermore,weak recrystallization texture components appear from the grain nucleation stage,regardless of the initial grain size,and are preserved after complete recrystallization due to uniform grain growth.The majority of recrystallization texture is deviated 20°–45°away from normal direction(ND),accounting for more than 50%.Especially,the recrystallization texture of the FG sample is a“Rare Earth texture”,in contrast to the widely reported texture modification unrelated to grain boundary nucleation.Only a scattered basal texture is observed in the CG sample,which also differs from the reported“Rare Earth texture”originating from shear band nucleation in dilute Mg–Gd alloys.Finally,based on the Johnson–Mehl–Avrami–Kolmogorov(JMAK)model,the recrystallization kinetics are calculated,and it is found that the initial grain size mainly affects the nucleation rate,and has limited effect on the grain growth rate. 展开更多
关键词 Mg-3Gd Grain size Microstructure evolution Recrystallization texture Recrystallization kinetics
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婴童运动护具中异噻唑啉酮汗液迁移限值模型的构建
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作者 马彤梅 朱镇海 +4 位作者 李琼 黄理纳 霍炜强 方晗 刘作起 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第7期72-80,共9页
婴童的生理特征和行为模式与成人存在一定差异,导致其在使用相同类型产品时,对有害化学物质的暴露频率及暴露量远高于成人。因此,各国法规标准对婴童用品设置了有害化学物质的安全限值,用以保护最脆弱且敏感的婴童群体。异噻唑啉酮是一... 婴童的生理特征和行为模式与成人存在一定差异,导致其在使用相同类型产品时,对有害化学物质的暴露频率及暴露量远高于成人。因此,各国法规标准对婴童用品设置了有害化学物质的安全限值,用以保护最脆弱且敏感的婴童群体。异噻唑啉酮是一种能引起过敏性皮炎的强致敏性化合物,国内尚未设置其化学安全限值,国外也仅限于对其总含量的限制。为此,文中通过考察婴童的化学安全评估方法,总结现有化学安全限值模型,明确了构建限值模型的关键步骤。首先确定剂量反应数据;接着根据产品使用特征确定限值的量纲;然后基于量纲分析法,引入产品特征和人体行为模式参数,建立剂量反应数据与限值之间的联系。在此基础上,通过引入致敏阈值、总致敏评估因子、出汗率、运动时长构建了婴童运动护具中异噻唑啉酮汗液迁移限值模型。最后,结合婴童及产品特征选择合适的参数值,并应用该模型计算出3种异噻唑啉酮(MI、CMI和BIT)的迁移限值,分别为0.150、0.014和0.150 mg/L。该值拟在2023年底公布的国家标准《婴童用品日常运动防护器具通用技术要求》中被应用,用以保障婴童皮肤免受异噻唑啉酮的危害。 展开更多
关键词 婴童运动护具 异噻唑啉酮 化学安全限值模型 汗液迁移
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First Record of Cyclocarya from the Early Oligocene Qaidam Basin,North Xizang:Implications for the Paleogeography and Paleoecology
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作者 Yafei Hou Bowen Song +3 位作者 Xiangchuan Li fang han Xu Zhang Kexin Zhang 《Journal of Earth Science》 SCIE CAS CSCD 2024年第1期201-211,共11页
As the largest intermontane basin in the northeastern Tibetan Plateau(TP),the Qaidam Basin provides unique insight into paleoclimatic change and its relationship with global change and uplift on the TP.In this study,b... As the largest intermontane basin in the northeastern Tibetan Plateau(TP),the Qaidam Basin provides unique insight into paleoclimatic change and its relationship with global change and uplift on the TP.In this study,based on morphological comparison,fossil fruit of Cyclocarya from the Early Oligocene Shangganchaigou Formation in the Qaidam Basin is assigned as Cyclocarya cf.weylandii.The discovery of Cyclocarya cf.weylandii demonstrates the occurrence of Cyclocarya in the Oligocene sediment in Qaidam Basin.This is the first record of Cyclocarya fossil of Early Oligocene Age in China and indicates that Cyclocarya has existed on the northeastern TP since at least the Early Oligocene.The living analogues of the current fossil now lives in sub-tropical China,where the East Asian Monsoon is prevalent.Integrating the new fossils and previously reported fossil remains of plants and fishes,it can be inferred that the Early Oligocene Qaidam Basin was primarily influenced by westerly circulation and had a relatively warm and humid climate,which was in sharp contrast to the present-day climate in Qaidam Basin. 展开更多
关键词 BIOSTRATIGRAPHY climate change winged-fruit fossil Qaidam Basin Early Oligocene paleoclimate PALEOGEOGRAPHY
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桥梁复合材料防车撞吸能结构碰撞性能分析 被引量:20
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作者 潘晋 方涵 +1 位作者 吴亚锋 许明财 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2018年第8期122-127,共6页
针对在桥墩周围安装吸能结构可以降低车辆撞击对桥梁的情况,基于全尺寸复合材料吸能结构的台车撞击试验,通过对比试验和数值模拟结果验证有限元模型的有效性.在此基础上,考虑实际中更高撞击能量的情况,采用有限元方法分析不同撞击速度... 针对在桥墩周围安装吸能结构可以降低车辆撞击对桥梁的情况,基于全尺寸复合材料吸能结构的台车撞击试验,通过对比试验和数值模拟结果验证有限元模型的有效性.在此基础上,考虑实际中更高撞击能量的情况,采用有限元方法分析不同撞击速度的吸能结构响应,并研究不同结构材料的耐撞性能.钢夹层结构能够吸收大部分动能并有效减小局部损伤,而复合材料蜂窝结构可以起到很好的支撑作用,同时把撞击力比较均匀地分散到整体结构,使更多结构参与吸能.计算结果表明钢夹层-蜂窝复合材料防车撞吸能结构具有良好的耐撞性能. 展开更多
关键词 桥梁 车辆 有限元方法 蜂窝结构 复合材料
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桥墩复合材料防车撞结构碰撞性能试验研究 被引量:13
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作者 潘晋 方涵 +1 位作者 吴亚锋 许明财 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2018年第10期14-20,共7页
针对桥墩车辆碰撞的问题,设计了钢夹层和蜂窝复合材料相结合的桥梁防车撞吸能结构.为研究耐撞性能进行了材料性能试验和全尺寸防撞结构的碰撞试验,试验得到最大碰撞力为547.6 kN.通过对比试验获得碰撞响应与规范设计值,得出试验结果满... 针对桥墩车辆碰撞的问题,设计了钢夹层和蜂窝复合材料相结合的桥梁防车撞吸能结构.为研究耐撞性能进行了材料性能试验和全尺寸防撞结构的碰撞试验,试验得到最大碰撞力为547.6 kN.通过对比试验获得碰撞响应与规范设计值,得出试验结果满足碰撞条件容差要求,可用于后期的数值模型验证,为类似吸能结构的设计提供参考.钢夹层-复合材料桥梁防车撞吸能结构可以减小桥墩的局部损伤和整体破坏,从而达到保护桥墩的目的. 展开更多
关键词 桥梁 车辆 碰撞 试验 纤维增强复合材料
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Evaluating the Relationship between National Park Management and Local Communities’ Perceptions Based on Survey, a Case of Nyungwe National Park, Rwanda 被引量:2
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作者 Anathalie Nyirarwasa fang han +6 位作者 Xumei Pan Richard Mind’je Albert Poponi Maniraho Aboubakar Gasirabo Madeleine Udahogora Zacharia Florence Mtewele Edovia Dufatanye Umwali 《Journal of Geoscience and Environment Protection》 2020年第12期108-126,共19页
A sustainable management of national park requires collaboration between park staff, NGOs, local organizations and stakeholders, and government intervention. This collaboration promotes community-based welfare and ins... A sustainable management of national park requires collaboration between park staff, NGOs, local organizations and stakeholders, and government intervention. This collaboration promotes community-based welfare and inspires a sense of responsibility, thus promoting more benefits than conflicts. A survey administered to residents surrounding Nyungwe National Park was used to evaluate the relationship between Nyungwe National Park management and local communities. The residents acknowledged a positive attitude towards participating in conservation organizations where there was involvement, while a negative response revealed weak community mobilization. The community’s opinions about protection and tourism progression noted weak conflict resolution, but a positive attitude towards tourism activities in the area since they believed employment was likely as a result. In addition, the residents asked for support from government investments and stakeholders to develop the local private sector, and asked to be involved during the planning process. Approaches including the design of coordination mechanisms and integrated conservation and developments projects are suggested to promote a management structure leading to community involvement in conservation and tourism activities. This will increase visitor numbers and contribute to economic development not only in the region but also in the whole country. Empirical studies along with the factors shaping tourism and conservation activities should be considered as the basis for sustainable decision and policy making for sustainable management, and will contribute to government, stakeholders and park manager collaborations at Nyungwe national park. 展开更多
关键词 National Park Management Local Communities Implementation Residents’ Attitudes Coordination Mechanism
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