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基于空间马尔科夫链的粮食生产韧性动态演进及趋势预测
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作者 郑家喜 赵妍 卫增 《华中农业大学学报(社会科学版)》 北大核心 2024年第3期104-117,共14页
提高粮食生产韧性对保障粮食安全、加快建设农业强国具有重要意义。基于2005-2021年中国省级面板数据,构建粮食生产韧性评价指标体系进行水平测度,在此基础上深入分析其时空动态演进并展开趋势预测。研究表明:第一,考察期内中国粮食生... 提高粮食生产韧性对保障粮食安全、加快建设农业强国具有重要意义。基于2005-2021年中国省级面板数据,构建粮食生产韧性评价指标体系进行水平测度,在此基础上深入分析其时空动态演进并展开趋势预测。研究表明:第一,考察期内中国粮食生产韧性水平总体呈现逐年提升态势,但近些年增速有所放缓。第二,各省份粮食生产韧性差异明显,整体呈现“东高西低”的特征,且总体差距在考察期内逐步扩大;总体差异主要来源于区域间差异,但2017年后区域间差异逐渐下降,区域内差异逐步成为造成总体差异的主要原因;分区之间发展不平衡问题较为严峻,区域内省际差异明显。第三,中国粮食生产韧性存在较为显著的空间相关性,表现出明显的高-高集聚和低-低集聚特征,即高水平省份多与一个或多个高水平省份相邻,而低水平省份邻域多为低水平省份。第四,各省份粮食生产韧性在短期内较难实现层级跨越;而在引入空间地理因素后,粮食生产韧性的稳定状态有动摇趋势,易表现出“强者恒强,弱者恒弱”的马太效应。 展开更多
关键词 粮食生产 韧性 空间马尔科夫链 动态演进
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Understory seedlings of Quercus mongolica survive by phenological escape
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作者 Shixiong Wu Ying Liu +2 位作者 Lulu He wei zeng Qijing Liu 《Forest Ecosystems》 SCIE CSCD 2024年第2期236-246,共11页
Understanding understory seedling regeneration mechanisms is important for the sustainable development of temperate primary forests in the context of increasingly intense climate warming events.The poor regeneration o... Understanding understory seedling regeneration mechanisms is important for the sustainable development of temperate primary forests in the context of increasingly intense climate warming events.The poor regeneration of dominant tree species,however,is one of the biggest challenges it faces at the moment.Especially,the regeneration of the shade-intolerant Quercus mongolica seedling is difficult in primary forests,which contrasts with the extreme abundance of understory seedlings in secondary forests.The mechanism behind the interesting phenomenon is still unknown.This study used in-situ monitoring and nursery-controlled experiment to investigate the survival rate,growth performance,as well as nonstructural carbohydrate (NSC) concentrations and pools of various organ tissues of seedlings for two consecutive years,further analyze the understory light availability and simulate the foliage carbon (C) gain in the secondary and primary forest.Results suggested that seedlings in the secondary forest had greater biomass allocation aboveground,height and specific leaf area (SLA) in summer,which allowed the seedling to survive longer in the canopy closure period.High light availability and positive C gain in early spring and late autumn are key factors affecting the growth and survival of understory seedlings in the secondary forest,whereas seedlings in the primary forest had annual negative carbon gain.Through the growing season,the total NSC concentrations of seedlings gradually decreased,whereas those of seedlings in the secondary forest increased significantly in autumn,and were mainly stored in roots for winter consumption and the following year's summer shade period,which was verified by the nursery-controlled experiment that simulated autumn enhanced light availability improved seedling survival rate and NSC pools.In conclusion,our results revealed the survival trade-off strategies of Quercus mongolica seedlings and highlighted the necessity of high light availability during the spring and autumn phenological periods for shade-intolerant tree seedling recruitment. 展开更多
关键词 Carbon gain Nonstructural carbohydrate RECRUITMENT Trade-off Biomass allocation
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浅析“双碳”背景下我国城镇污水处理厂的发展方向及工程案例
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作者 吴幼娥 曾伟 +1 位作者 王伟浩 胡礼振 《新疆钢铁》 2024年第2期46-48,共3页
随着我国“碳达峰”与“碳中和”目标的相继确立,市政污水处理行业的相关政策亦随之陆续落地。本文深入剖析了污水处理厂在碳减排与碳中和方面的实施路径,并指出了构建能源自给型污水处理厂的核心要素。通过对桐梓县城某污水处理厂二期... 随着我国“碳达峰”与“碳中和”目标的相继确立,市政污水处理行业的相关政策亦随之陆续落地。本文深入剖析了污水处理厂在碳减排与碳中和方面的实施路径,并指出了构建能源自给型污水处理厂的核心要素。通过对桐梓县城某污水处理厂二期扩建工程的案例研究,发现在新工艺技术的引入下,通过节能降耗、降低药耗、回收有机物能源、利用光伏发电以及水源热泵能量回收等多方面,VFL工艺污水处理厂能够实现能源自给,甚至达到碳中和的目标,为我国建设“碳中和”污水处理厂提供了有力的技术支撑。 展开更多
关键词 “双碳” 城镇污水处理厂 VFL工艺
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发展特色农业产业壮大新型农村集体经济的理论逻辑、实践样态以及优化路径:以新疆为例 被引量:6
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作者 郑家喜 卫增 +1 位作者 尤庆南 王祥明 《华中农业大学学报》 CAS CSCD 北大核心 2023年第5期269-281,共13页
培育特色农业产业是推动新型农村集体经济稳定发展和可持续增长的重要动力。基于新疆特色农业产业发展在壮大新型农村集体经济的实践案例,归纳总结出因地制宜、引入现代化管理方式、紧密连接新型农村集体经济组织成员、注重内外部资本... 培育特色农业产业是推动新型农村集体经济稳定发展和可持续增长的重要动力。基于新疆特色农业产业发展在壮大新型农村集体经济的实践案例,归纳总结出因地制宜、引入现代化管理方式、紧密连接新型农村集体经济组织成员、注重内外部资本要素积累和扩大再生产的投入、探索抱团发展的多种模式的新疆经验,分析了人才匮乏、缺乏长远规划、管理体制不完善以及政策支持体系不健全等诸多问题,并提出构建人力资本引育机制、宣传推介机制、产权激励机制、产业培育机制、政策引导机制的优化路径,以期优化发展新疆特色农业产业、壮大新型农村集体经济的实践路径,并为其他地区提供经验借鉴。 展开更多
关键词 特色农业产业 新型农村集体经济 产业培育 新疆
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基于加速康复外科理念的去阿片化麻醉镇痛在急诊剖宫产围手术期运用观察 被引量:7
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作者 吴靦 代文化 +6 位作者 曾伟 谢焕龙 李宇琴 蒋红娥 吴演文 张慧 刘前梅 《药物流行病学杂志》 CAS 2023年第2期166-172,共7页
目的探讨基于加速康复外科理念的去阿片化麻醉镇痛在腰硬联合麻醉后急诊剖宫产围手术期的临床运用效果。方法300例急诊剖宫产患者随机分为去阿片化组(OF组)、舒芬太尼组(S组)、吗啡组(M组),每组100例。3组患者术前均采用加速康复外科策... 目的探讨基于加速康复外科理念的去阿片化麻醉镇痛在腰硬联合麻醉后急诊剖宫产围手术期的临床运用效果。方法300例急诊剖宫产患者随机分为去阿片化组(OF组)、舒芬太尼组(S组)、吗啡组(M组),每组100例。3组患者术前均采用加速康复外科策略。OF组术中采用非阿片类药物麻醉镇痛,术毕予氟比洛芬酯+右美托咪定静脉自控镇痛;S组术中予舒芬太尼镇痛,术毕予舒芬太尼+右美托咪定静脉自控镇痛;M组术中予舒芬太尼镇痛,术后予吗啡+罗哌卡因行硬膜外自控镇痛。OF组和S组患者术毕行B超引导下的腰方肌神经阻滞。比较3组患者手术治疗到出院时间、术后首次下床时间、术后24 h产科恢复质量-11评分、术后48 h内动态视觉模拟评分、围手术期并发症等情况。结果与M组相比,OF组和S组手术治疗到出院时间明显缩短,下床活动时间更早,产科恢复质量-11评分更高,皮肤瘙痒发生率更低(P<0.05)。与M组和S组相比,OF组围术期恶心呕吐、腹胀发生率更低(P<0.05)。3组患者的动态视觉模拟评分以及围手术期寒颤、头晕头痛、尿潴留等发生率差异无统计学意义(P>0.05)。结论去阿片化麻醉镇痛在腰硬联合麻醉后急诊剖宫产围手术期中运用效果满意,可缩短剖宫产后住院时间,减少围术期并发症。 展开更多
关键词 加速康复外科 去阿片化麻醉 急诊剖宫产 腰方肌阻滞 多模式镇痛
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室温多向压缩道次变形量对AZ80镁合金力学性能影响 被引量:2
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作者 魏增 张宝红 +1 位作者 吴卓阳 何金文 《精密成形工程》 北大核心 2023年第1期79-85,共7页
目的探明室温塑性变形对AZ80塑性、硬度及最大应力等力学性能的影响规律,为其成形工艺参数制定提供依据。方法对挤压态AZ80镁合金均匀化处理后,在室温下控制道次变形量(0.05、0.075、0.1)及累积应变进行多向多道次压缩变形;利用力学试... 目的探明室温塑性变形对AZ80塑性、硬度及最大应力等力学性能的影响规律,为其成形工艺参数制定提供依据。方法对挤压态AZ80镁合金均匀化处理后,在室温下控制道次变形量(0.05、0.075、0.1)及累积应变进行多向多道次压缩变形;利用力学试验机和维氏硬度计分析道次变形量与累积应变对其力学性能的影响。结果在室温下,当AZ80镁合金单向压缩的真应变达到0.124时会发生开裂,通过小应变多向多道次压缩可以将累积应变至少提高至3.6以上。在道次变形量为0.05、0.075和0.1时,累积应变分别可达到7.5、6和3.7;在累积应变为3.6时,随着道次变形量的增加试样硬度(HV)分别达到94、110和121,较未变形试样硬度(70HV)分别提升了33%、57%和73%。结论AZ80镁合金通过室温多向多道次压缩有利于改善材料塑性,提高力学性能。其塑性随着道次变形量的减小而提高,硬度和最大应力随道次变形量和累积应变的增加而升高,且道次变形量比累积应变对硬度和最大应力的影响更大。 展开更多
关键词 晶粒细化 镁合金 室温 多向压缩 挤压态 力学性能
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乙二醇替代水增塑聚乙烯醇吹塑膜的制备与性能
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作者 曾威 石伊康 +4 位作者 吴星宇 白忠宁 邓金玉 王劭妤 程博闻 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第12期88-96,共9页
水作为增塑剂在聚乙烯醇(PVA)的熔融加工过程中起到至关重要的作用,但在高温条件下水容易爆沸蒸发而影响到加工过程的稳定性和最终产品的性能。文中采用乙二醇作为水的替代增塑剂,首先利用Materials Studio软件基于分子动力学原理对PVA... 水作为增塑剂在聚乙烯醇(PVA)的熔融加工过程中起到至关重要的作用,但在高温条件下水容易爆沸蒸发而影响到加工过程的稳定性和最终产品的性能。文中采用乙二醇作为水的替代增塑剂,首先利用Materials Studio软件基于分子动力学原理对PVA与增塑剂的混合模型进行模拟,分析了乙二醇替代水的可行性。发现乙二醇与PVA的相容性比水更好,结合能更大,可以有效降低PVA分子间作用力,拓宽PVA的热加工窗口,便于熔融挤出加工。然后通过挤出吹塑法制备了热塑性聚乙烯醇(TPVA)薄膜,并考察了乙二醇用量对PVA性能的影响。结果表明,随乙二醇用量的增加,TPVA的熔点和结晶度逐渐降低,熔体流动速率逐渐增大,起增塑作用的乙二醇含量不超过10.0%,且2.5%的乙二醇即可达到5.0%水的增塑效果。当乙二醇含量为10.0%时,PVA薄膜的阻隔性能优异,其氧气透过量为47.82 cm^(3)/(m^(2)·d·0.1MPa),吸油率为0.215%。 展开更多
关键词 聚乙烯醇 乙二醇 增塑 熔融加工 分子动力学
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Nanotechnologies meeting natural sources:Engineered lipoproteins for precise brain disease theranostics
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作者 Ruoning Wang Xinru Zhang +6 位作者 Kuanhan Feng wei zeng Jie Wu Danni Sun Ziyi Lu Hao Feng Liuqing Di 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2023年第5期77-98,共22页
Biological nanotechnologies have provided considerable opportunities in the management of malignancies with delicate design and negligible toxicity,from preventive and diagnostic to therapeutic fields.Lipoproteins,bec... Biological nanotechnologies have provided considerable opportunities in the management of malignancies with delicate design and negligible toxicity,from preventive and diagnostic to therapeutic fields.Lipoproteins,because of their inherent blood-brain barrier permeability and lesion-homing capability,have been identified as promising strategies for high-performance theranostics of brain diseases.However,the application of natural lipoproteins remains limited owing to insufficient accumulation and complex purification processes,which can be critical for individual therapeutics and clinical translation.To address these issues,lipoprotein-inspired nano drug-delivery systems(nano-DDSs),which have been learned from nature,have been fabricated to achieve synergistic drug delivery involving site-specific accumulation and tractable preparation with versatile physicochemical functions.In this review,the barriers in brain disease treatment,advantages of state-of-the-art lipoprotein-inspired nano-DDSs,and bio-interactions of such nano-DDSs are highlighted.Furthermore,the characteristics and advanced applications of natural lipoproteins and tailor-made lipoprotein-inspired nano-DDSs are summarized.Specifically,the key designs and current applications of lipoprotein-inspired nano-DDSs in the field of brain disease therapy are intensively discussed.Finally,the current challenges and future perspectives in the field of lipoprotein-inspired nano-DDSs combined with other vehicles,such as exosomes,cell membranes,and bacteria,are discussed. 展开更多
关键词 Biological modulation Brain diseases Blood-brain barrier LIPOPROTEINS THERANOSTICS
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Photometric Monitoring of Blazar 3C 66A with the Yunnan University Astronomical Observatory 1 m Telescope
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作者 wei zeng Tao Wen +4 位作者 Zhen-Lu Gong Shi Chen Fan Wu Hao-Yang Zhang Ben-Zhong Dai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第4期148-163,共16页
3C 66A is one of our first batches of photometric monitoring objects with the 1 m optical telescope at Yunnan University Astronomical Observatory.In the present work,the observational campaign was performed from 2021 ... 3C 66A is one of our first batches of photometric monitoring objects with the 1 m optical telescope at Yunnan University Astronomical Observatory.In the present work,the observational campaign was performed from 2021 November 1 to 2022 February 27 in the Johnson-Morgan system V and R bands.The average magnitudes in each band were■=15.52±0.18 mag and■=15.07±0.17 mag.The overall variability amplitudes wereΔV=■,Amp=70.27%andΔR=■,Amp=68.56%,respectively.Most of the intraday variabilities(IDVs)occurred in 2021 December and 2022 February.The minimal rise/decay timescale was about 6 minutes(5.82±2.74 minutes and 6.18±2.81 minutes on 2022 February 11,6.99±3.70 minutes and 6.17±2.91 minutes on 2022 February 12).Durations of these rapid variabilities were from 11.99 to 179.67 minutes.The discrete correlation function analyses between V and R bands showed significantly correlated variability.Color index analysis of ID Vs showed that the spectrums do not change with variabilities. 展开更多
关键词 (galaxies:)BL Lacertae objects individual(3C 66A)-galaxies photometry-galaxies active
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54例2型糖尿病患者合并新型冠状病毒感染的死亡原因分析
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作者 位增 曹灵 +3 位作者 佘敦敏 刘彦 王艳 张真稳 《临床荟萃》 CAS 2023年第9期806-812,共7页
目的研究2型糖尿病(T2DM)患者合并新型冠状病毒感染(COVID-19)的死亡患者的临床特点及死亡的可能影响因素。方法回顾性分析2022年12月至2023年2月扬州大学临床医学院T2DM合并COVID-19患者在住院期间发生死亡的情况,详细记录患者一般资... 目的研究2型糖尿病(T2DM)患者合并新型冠状病毒感染(COVID-19)的死亡患者的临床特点及死亡的可能影响因素。方法回顾性分析2022年12月至2023年2月扬州大学临床医学院T2DM合并COVID-19患者在住院期间发生死亡的情况,详细记录患者一般资料及实验室检查资料,并对患者入院初期的检测指标与入院终末期复查指标进行对比。结果54例死亡患者平均年龄为(74.31±10.64)岁;50例(92.6%)合并其他基础疾病,74%的患者合并2种以上基础疾病。与入院初期检查结果相比,死亡前最后一次血糖、酸碱度、红细胞计数、白蛋白、球蛋白明显下降。二氧化碳分压(PCO_(2))、乳酸、乳酸脱氢酶(LDH)、血钠、肌红蛋白、凝血酶原时间、降钙素原、C反应蛋白、D-二聚体明显升高,差异均有统计学意义(P均<0.05)。54例死亡患者中有96.3%的患者胸部CT影像学改变为双肺存在大片斑片状阴影及磨玻璃样影,81.5%的患者同时合并双肺胸腔积液。Logistic回归分析结果表明,PCO_(2)、LDH是T2DM合并COVID-19患者死亡的独立危险因素。结论T2DM合并COVID-19患者预后不佳,PCO_(2)、LDH是影响T2DM合并COVID-19患者死亡的独立危险因素。 展开更多
关键词 新型冠状病毒感染 2型糖尿病 死亡原因 二氧化碳分压 乳酸脱氢酶 危险因素
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多种结构聚醚砜纤维过滤膜的制备及过滤性能 被引量:5
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作者 卫志美 刘振艳 +3 位作者 王劭妤 杨杰 曾威 王孝军 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第11期101-108,共8页
高效去除污水中亚微米级污染物颗粒的分离膜是研究学者们一直关注的热点。文中利用静电纺丝技术制备出多种结构聚醚砜(PES)纤维过滤膜,系统研究了PES纤维过滤膜的通量及孔隙率变化规律,并以0.5μm和0.2μm聚苯乙烯(PS)作为亚微米级颗粒... 高效去除污水中亚微米级污染物颗粒的分离膜是研究学者们一直关注的热点。文中利用静电纺丝技术制备出多种结构聚醚砜(PES)纤维过滤膜,系统研究了PES纤维过滤膜的通量及孔隙率变化规律,并以0.5μm和0.2μm聚苯乙烯(PS)作为亚微米级颗粒模板,研究PES纤维过滤膜的过滤性能。研究结果表明,当纤维直径相近时,串珠结构纤维过滤膜的孔隙率和通量均高于光滑结构,但截留率较低。随着纤维膜厚度的增加,PES纤维膜的孔隙率和通量均减小,截留率增加。通过对比纤维膜对不同尺寸PS颗粒的截留性能,分析其截留机理。最后通过研究纤维膜的抗污性能发现串珠结构的纤维膜有更优异的抗污性能。所制备的PES纤维过滤膜有望在污水净化实际过程中对亚微米颗粒完成高效分离。 展开更多
关键词 静电纺丝 纤维膜 过滤性能 结构形貌
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振荡交换-抽滤淋洗结合凯氏定氮法快速测定土壤中的阳离子交换量 被引量:11
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作者 马怡飞 张尼 +2 位作者 魏增 高文旭 王奎 《岩矿测试》 CAS CSCD 北大核心 2019年第1期129-135,共7页
测定土壤阳离子交换量(CEC)的行业标准方法(LY/T1243—1999)是采取离心分离结合手工蒸馏进行滴定,耗时长、操作繁琐。为了缩短反应时间,提高检测效率,本文利用乙酸铵对酸性和中性土壤进行处理,用氯化铵-乙酸铵对石灰性土壤进行处理,应... 测定土壤阳离子交换量(CEC)的行业标准方法(LY/T1243—1999)是采取离心分离结合手工蒸馏进行滴定,耗时长、操作繁琐。为了缩短反应时间,提高检测效率,本文利用乙酸铵对酸性和中性土壤进行处理,用氯化铵-乙酸铵对石灰性土壤进行处理,应用振荡和抽滤装置快速交换和清洗阳离子,通过全自动凯氏定氮仪对吸附的铵根离子进行测定,由此计算CEC值。结果表明:在最佳的振荡和蒸馏时间、滴定酸浓度、指示剂配比等实验条件下,一个批次样品(100件)的分析流程仅需要12h,比传统方法检测时间缩短近80%。经国家标准物质验证,测定结果与推荐值相符,5次测定的相对标准偏差均小于1. 5%。本方法免去了多次离心分离操作,解决了待测成分损失、CEC测定值偏低的问题,提高了检测效率和准确度,较林业标准方法的成本低,可操作性强,适用于土壤环境质量评价、地区土壤抽样调查等大批量土壤样品分析。 展开更多
关键词 振荡 淋洗 全自动凯氏定氮仪 乙酸铵 氯化铵-乙酸铵 土壤 阳离子交换量
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温差疲劳载荷下热塑性聚氨酯弹性体对丙烯腈-丁二烯-苯乙烯共聚物性能的影响 被引量:5
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作者 曾威 李冉 +3 位作者 王钊智 苏情 王劭妤 王孝军 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第11期117-124,共8页
选用热塑性聚氨酯弹性体(TPU)提升温差疲劳载荷下丙烯腈-丁二烯-苯乙烯共聚物(ABS)耐应力开裂性能。研究了TPU的引入对温差疲劳载荷下材料力学性能和相态结构的影响,从流变性能和动态力学性能入手分析材料熔体弹性信息及界面流动行为,... 选用热塑性聚氨酯弹性体(TPU)提升温差疲劳载荷下丙烯腈-丁二烯-苯乙烯共聚物(ABS)耐应力开裂性能。研究了TPU的引入对温差疲劳载荷下材料力学性能和相态结构的影响,从流变性能和动态力学性能入手分析材料熔体弹性信息及界面流动行为,探讨了TPU含量对温差疲劳前后材料强度保留率的影响。实验结果表明,TPU中软段可以作为ABS基体中“等效橡胶”相,从而减小熔体流动阻力和温差疲劳引起的熔体黏度差异,同时提高温差疲劳后材料强度保留率。引入TPU组分后,复合材料断面空穴形态变化放大了温差疲劳过程中基体胀缩的物理损伤,同时消耗了温差疲劳损伤,提高了材料的耐温差疲劳性能,有利于减弱温差对ABS性能的影响,减少材料开裂,延长制品使用寿命。 展开更多
关键词 热塑性聚氨酯弹性体 温差疲劳 等效橡胶 开裂 力学性能
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空气过滤用聚芳硫醚砜/纳米二氧化硅复合静纺纳米纤维膜的制备及应用 被引量:4
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作者 赵伟 王劭妤 +2 位作者 卫志美 曾威 王孝军 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第10期141-148,共8页
在纺丝液中添加疏水性气相纳米二氧化硅(SiO2),通过静电纺丝制备了具有自清洁性能的二氧化硅/聚芳硫醚砜(SiO2/PASS)复合纳米纤维膜。使用场发射扫描电镜(FESEM)观察了SiO2不同含量的SiO2/PASS复合纤维膜的形貌,并对纤维膜进行了元素(E... 在纺丝液中添加疏水性气相纳米二氧化硅(SiO2),通过静电纺丝制备了具有自清洁性能的二氧化硅/聚芳硫醚砜(SiO2/PASS)复合纳米纤维膜。使用场发射扫描电镜(FESEM)观察了SiO2不同含量的SiO2/PASS复合纤维膜的形貌,并对纤维膜进行了元素(EDS)和红外光谱(FT-IR)分析,FESEM、EDS和FT-IR的结果表明,纳米SiO2加入到纤维膜可形成多级微纳结构。对纤维膜的平均孔径分析,表明纳米SiO2的加入会增大纤维膜的孔径;对纤维膜的空气过滤性能的探究发现,在一定条件下适当增加纤维膜的面密度可以提高纤维膜的综合过滤性能,面密度为3.46 g/m^2的4-SiO2/PASS复合纤维膜的综合过滤效率最佳,品质因数可达0.03549 Pa^(-1)。SiO2/PASS复合纳米纤维膜的高效过滤和超疏水特性可以使其在空气过滤领域有广泛的应用。 展开更多
关键词 纳米二氧化硅 自清洁 聚芳硫醚砜 纳米纤维 空气过滤
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A New Free-Standing Aqueous Zinc-Ion Capacitor Based on MnO2–CNTs Cathode and MXene Anode 被引量:9
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作者 Siliang Wang Qiang Wang +3 位作者 wei zeng Min Wang Limin Ruan Yanan Ma 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第4期227-238,共12页
Restricted by their energy storage mechanism,current energy storage devices have certain drawbacks,such as low power density for batteries and low energy density for supercapacitors.Fortunately,the nearest ion capacit... Restricted by their energy storage mechanism,current energy storage devices have certain drawbacks,such as low power density for batteries and low energy density for supercapacitors.Fortunately,the nearest ion capacitors,such as lithium-ion and sodium-ion capacitors containing battery-type and capacitor-type electrodes,may allow achieving both high energy and power densities.For the inspiration,a new zinc-ion capacitor(ZIC)has been designed and realized by assembling the free-standing manganese dioxide-carbon nanotubes(MnO2-CNTs)battery-type cathode and MXene(Ti3C2Tx)capacitortype anode in an aqueous electrolyte.The ZIC can avoid the insecurity issues that frequently occurred in lithium-ion and sodium-ion capacitors in organic electrolytes.As expected,the ZIC in an aqueous liquid electrolyte exhibits excellent electrochemical performance(based on the total weight of cathode and anode),such as a high specific capacitance of 115.1 F g?1(1 mV s?1),high energy density of 98.6 Wh kg?1(77.5 W kg?1),high power density of 2480.6 W kg?1(29.7 Wh kg?1),and high capacitance retention of^83.6%of its initial capacitance(15,000 cycles).Even in an aqueous gel electrolyte,the ZIC also exhibits excellent performance.This work provides an essential strategy for designing next-generation high-performance energy storage devices. 展开更多
关键词 Energy storage Zinc-ion CAPACITOR Battery-type and capacitor-type electrodes MXene Electrochemical performance
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Low-Temperature Growing Anatase TiO2/SnO2 Multi-dimensional Heterojunctions at MXene Conductive Network for High-Efficient Perovskite Solar Cells 被引量:7
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作者 Linsheng Huang Xiaowen Zhou +7 位作者 Rui Xue Pengfei Xu Siliang Wang Chao Xu wei zeng Yi Xiong Hongqian Sang Dong Liang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第3期199-217,共19页
A multi-dimensional conductive heterojunction structure,composited by TiO2,SnO2,and Ti3C2TX MXene,is facilely designed and applied as electron transport layer in efficient and stable planar perovskite solar cells.Base... A multi-dimensional conductive heterojunction structure,composited by TiO2,SnO2,and Ti3C2TX MXene,is facilely designed and applied as electron transport layer in efficient and stable planar perovskite solar cells.Based on an oxygen vacancy scramble effect,the zero-dimensional anatase TiO2 quantum dots,surrounding on two-dimensional conductive Ti3C2TX sheets,are in situ rooted on three-dimensional SnO2 nanoparticles,constructing nanoscale TiO2/SnO2 heterojunctions.The fabrication is implemented in a controlled lowtemperature anneal method in air and then in N2 atmospheres.With the optimal MXene content,the optical property,the crystallinity of perovskite layer,and internal interfaces are all facilitated,contributing more amount of carrier with effective and rapid transferring in device.The champion power conversion efficiency of resultant perovskite solar cells achieves 19.14%,yet that of counterpart is just 16.83%.In addition,it can also maintain almost 85%of its initial performance for more than 45 days in 30–40%humidity air;comparatively,the counterpart declines to just below 75%of its initial performance. 展开更多
关键词 In situ fabrication Multi-dimensional heterojunction Oxygen vacancy scramble effect Electron transport layer Perovskite solar cells
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Hierarchically porous Cu current collector with lithiophilic CuxO interphase towards high-performance lithium metal batteries 被引量:5
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作者 Yaya Wang Zexu Zhao +4 位作者 wei zeng Xingbo Liu Lei Wang Jian Zhu Bingan Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第7期292-299,共8页
Lithium metal is one of the most promising anode materials for next-generation electrochemical energy storage due to low electrochemical potential and high specific capacity.However,large volume change and uncontrolla... Lithium metal is one of the most promising anode materials for next-generation electrochemical energy storage due to low electrochemical potential and high specific capacity.However,large volume change and uncontrollable formation of lithium dendrite during cycling severely hinder the practical application of rechargeable Li metal batteries.Herein,we report a hierarchically porous Cu covered with lithiophilic CuxO(HPCu-CuxO) via femtosecond laser strategy in about 2 min as current collector for highperformance Li metal batteries.With precisely tunable pore volume and depth as well as lithiophilic CuxO interphase,the HPCu-CuxO not only guides homogeneous Li nucleation,resulting in a smooth and dendrite-free lithium surface,but also provides space to alleviate the volume expansion of Li metal anode,achieving excellent structure stability.Consequently,highly stable Coulombic efficiency and ultralow overpotential of 15 mV even up to 1000 h were achieved at the current density of 1 mA cm^(-2).Moreover,the resultant Li@HPCu-CuxO//LiFePO_(4) full battery delivered outstanding cycle stability and rate capability.These results offer a pathway toward high-energy-density and safe rechargeable Li metal batteries. 展开更多
关键词 Lithium metal batteries Femtosecond laser strategy Hierarchically porous structure Lithiophilic CuxO interphase
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Dioxygen Affinities and Catalytic Oxidation Performance of Cobalt (Ⅱ)Complexes with N—Aryl Hydroxamic Acid 被引量:4
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作者 Chun Chun ZHANG wei zeng +1 位作者 Jian Zhang LI Sheng Ying QIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第6期627-630,共4页
The oxygenation of cobalt (II) hydroxamates (CoL2) and its catalytic performance in oxidation of p-xylene to p-toluic acid (PTA) were examined. The effects of X and Y bonded to hydroxamate group on dioxygen affinitie... The oxygenation of cobalt (II) hydroxamates (CoL2) and its catalytic performance in oxidation of p-xylene to p-toluic acid (PTA) were examined. The effects of X and Y bonded to hydroxamate group on dioxygen affinities and catalytic oxidation performance were also investigated. 展开更多
关键词 Cobalt (II) hydroxamates dioxygen affinities catalytic oxidation p-xylene.
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微波消解-电感耦合等离子体质谱法测定砂仁中的铜、铅、砷、镉 被引量:6
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作者 王奎 张尼 +1 位作者 魏增 马怡飞 《化学分析计量》 CAS 2018年第5期25-28,共4页
建立了微波消解样品,电感耦合等离子体质谱法(ICP–MS)测定黔西南高砷土壤种植的砂仁中痕量铜、铅、砷、镉的分析方法。对微波消解条件进行了优化。为了避免消解试剂对质谱测定的干扰,选择硝酸–双氧水混合溶液(体积比为3∶1)作为微波... 建立了微波消解样品,电感耦合等离子体质谱法(ICP–MS)测定黔西南高砷土壤种植的砂仁中痕量铜、铅、砷、镉的分析方法。对微波消解条件进行了优化。为了避免消解试剂对质谱测定的干扰,选择硝酸–双氧水混合溶液(体积比为3∶1)作为微波消解试剂,采用ICP–MS测定消解液中铜、铅、砷、镉的含量。利用校正方程对砷、镉的质谱干扰进行校正。铜、铅、砷、镉4种元素的线性相关系数均大于0.999 2,检出限分别为0.073,0.048,0.39,0.062μg/L,测定结果的相对标准偏差小于4.5%(n=5)。各元素的加标回收率在96.0%~105.0%之间。该方法样品处理快速、简单,溶解率高,测定结果准确、可靠,适用于成批量砂仁样品中铜、铅、砷、镉微量元素的测定。 展开更多
关键词 微波消解 电感耦合等离子体质谱法 砂仁
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Thrombophilia Caused by Beta2-Glycoprotein I Deficiency: In Vitro Study of a Rare Mutation in APOH Gene 被引量:3
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作者 Xiao-ping ZHANG wei zeng +7 位作者 Hui LIU Liang TANG Qing-yun WANG Zhi-peng CHENG Ying-ying WU Bei HU wei SHI Yu HU 《Current Medical Science》 SCIE CAS 2018年第2期379-385,共7页
This study aimed to explore the mechanism of a novel mutation (p.Lys38Glu) in apolipoprotein H (APOH) gene causing hereditary beta2-glycoprotein I (β2GPI) deficiency and thrombosis in a proband with thrombophil... This study aimed to explore the mechanism of a novel mutation (p.Lys38Glu) in apolipoprotein H (APOH) gene causing hereditary beta2-glycoprotein I (β2GPI) deficiency and thrombosis in a proband with thrombophilia. The plasma level of β2GPI was measured by ELISA and Western blotting, and anti-β2GPI antibody by ELISA. Lupus anticoagulant (LA) was assayed using the dilute Russell viper venom time. Deficiency of the major natural anticoagulants including protein C (PC), protein S (PS), antithrombin (AT) and thrombomodulin (TM) was excluded from the proband. A mutation analysis was performed by amplification and sequencing of the APOH gene. Wild type and mutant (c.112A〉G) APOH expression plasmids were constructed and transfected into HEK293T cells. The results showed that the thrornbin generation capacity of the proband was higher than that of the other family members. Missense mutation p.Lys38Glu in APOH gene and LA coexisted in the proband. The mutation led to β2GPI deficiency and thrombosis by impairing the protein production and inhibiting the platelet aggregation. It was concluded that the recurrent thrombosis of the proband is associated with the coexistence ofp.Lys38Glu mutation in APOH gene and LA in plasma. 展开更多
关键词 beta2-glycoprotein I lupus anticoagulant MUTATION apolipoprotein H THROMBOPHILIA
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