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Study on Limited Filamentous Sludge Bulking Test in A/O Activated Sludge Process
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作者 万玉山 孙凌峰 +2 位作者 贾春霞 李娜 雷春生 《Agricultural Science & Technology》 CAS 2014年第9期1620-1623,共4页
[Objective] This study aimed to make use of the limited filamentous sludge bulking characteristics to purify water quality and save energy. [Method] The effects of dissolved oxygen (DO) on sludge bulking were explor... [Objective] This study aimed to make use of the limited filamentous sludge bulking characteristics to purify water quality and save energy. [Method] The effects of dissolved oxygen (DO) on sludge bulking were explored by changing the DO con- centration in the aerobiotic pool of NO system from the low load (0.25 kg COD/(kg MLSS.d)) and the medium to high load (0.55 kgCOD/(kg MLSSod)). [Result] In the NO activated sludge system, when the sludge load was 0.25 kg COD/(kg MLSS.d), DO=1.5 mg/L, the sludge index was at around 250, while when the sludge load- ing was 0.55 kg COD/(kg MLSS.d), DO=1.5 mg/L, the sludge index was close to 300, occurring the limited filamentous bulking. The bulked sludge still showed high removal rates to COD, SS, nitrogen and phosphorus. [Conclusion] It could improve the oxygen transfer rate and reduce the aeration rate at low DO conditions to achieve energy-saving. 展开更多
关键词 A/O process Limited filamentous sludge bulking Sludge load Energy saving
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Granulation of filamentous microorganisms in a sequencing batch reactor with saline wastewater 被引量:11
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作者 Zhihua Li Ting Zhang +1 位作者 Na Li Xiaochang Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第1期62-67,共6页
Proliferation of filamentous microorganisms frequently leads to operational failure for activate sludge systems. In this study, it was found that filamentous microorganisms could grow in compact granular structure wit... Proliferation of filamentous microorganisms frequently leads to operational failure for activate sludge systems. In this study, it was found that filamentous microorganisms could grow in compact granular structure with 5% sodium chloride in the substrate. In the early period of experiment, coccoid and rode-like bacteria predominated in the yellowish-brown granules, and later the white and the black granules were developed by filamentous microorganisms. The filamentous granules exhibited low porosity and fast settling velocity, and were more compact even than bacteria granules. It was hypothesized that the elevated pH in the later period might be a possible reason for the compact growth of filamentous granules. However, the bacteria granules showed the high bioactivity in terms of specific oxygen utilizing rate, and comprised of a wider diversity of compounds based on the thermogravimetric evaluation. The findings in this study demonstrated that filamentous microbes could form compact granular structure, which may encourage the utilization of filamentous microorganisms rather than the inhibition of their growth, as the latter is frequently used for sludge bulking control. 展开更多
关键词 aerobic granule sludge bulking filamentous microorganisms thermogravimetric analysis
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注册商标无效宣告绝对事由的正解与修订 被引量:1
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作者 孔祥俊 《知识产权》 CSSCI 北大核心 2024年第8期3-30,共28页
注册商标无效宣告的绝对事由需要在立法上进行必要的完善,回归宣告无效针对不正当注册的原意,确保商标核准注册与无效宣告程序中绝对事由的对应性和同一性,重点是尽快去除“欺骗手段或者其他不正当手段”的独立无效事由。在既有法律规定... 注册商标无效宣告的绝对事由需要在立法上进行必要的完善,回归宣告无效针对不正当注册的原意,确保商标核准注册与无效宣告程序中绝对事由的对应性和同一性,重点是尽快去除“欺骗手段或者其他不正当手段”的独立无效事由。在既有法律规定下,绝对无效事由的适用应当保持必要的谦抑,避免适用上的扩大化或者扭曲化。当前的商标确权实践应当突出强调实际使用的优越地位,避免过于强调商标申请注册时的“原罪”而无视实际使用的现实,导致无效宣告“舍本逐末”“缘木求鱼”;要真正认真对待两种事由的法律界限,尊重其区分价值,避免动辄以绝对事由变相发挥保护在先权利的相对事由功能,防止以绝对事由为名变相扩展在先权利,维护权利保护与商标秩序的平衡。 展开更多
关键词 注册商标无效宣告 绝对事由 相对事由 非使用性批量注册商标 欺骗手段 其他不正当手段
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非均匀散粒粗糙床面明渠紊流特性研究
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作者 徐翔宇 钟亮 +1 位作者 李国际 阎鑫铭 《中国农村水利水电》 北大核心 2024年第3期137-142,共6页
为揭示非均匀散粒粗糙床面明渠紊流特性,采用d_1=1.0 cm、d_2=1.5 cm的正方体散粒制成粗糙床面开展PIV水槽明渠紊流试验,探讨了紊动强度、速度高阶矩、雷诺应力和紊动能的分布规律。结果表明:(1)粒间区中部,邻近剖面颗粒的绕流作用使紊... 为揭示非均匀散粒粗糙床面明渠紊流特性,采用d_1=1.0 cm、d_2=1.5 cm的正方体散粒制成粗糙床面开展PIV水槽明渠紊流试验,探讨了紊动强度、速度高阶矩、雷诺应力和紊动能的分布规律。结果表明:(1)粒间区中部,邻近剖面颗粒的绕流作用使紊动强度发生明显变化。(2)速度高阶矩纵向偏度系数S_(u')与垂向偏度系数S_(v')的分布特性揭示在近床处主要发生扫掠事件,而颗粒顶部以上区域喷射事件占主导。(3)平均雷诺应力R_(mean)在粒间区沿程先增大再减小,在颗粒区先减小后增大。(4)紊动能呈条带状分布,在河床底部和水面受到的抑制使得整体紊动能从床面开始增大,在颗粒顶部附近达到最大之后开始减小。 展开更多
关键词 非均匀散粒粗糙 明渠紊流 紊动强度 速度高阶矩 雷诺应力 紊动能
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群体感应与群体淬灭控制丝状菌污泥膨胀的研究进展
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作者 刘涛 陈炳坚 +3 位作者 郭胜军 赖锡敏 殷旭东 谢文玉 《工业用水与废水》 CAS 2024年第5期13-19,共7页
活性污泥法净化污水过程中,丝状菌的过度生长导致污泥膨胀。利用微生物群体感应机制是控制丝状菌膨胀的一种新兴策略。介绍了丝状菌膨胀的控制策略及微生物群体感应的作用机制,综述了群体感应与群体淬灭控制丝状菌膨胀的研究进展,分析... 活性污泥法净化污水过程中,丝状菌的过度生长导致污泥膨胀。利用微生物群体感应机制是控制丝状菌膨胀的一种新兴策略。介绍了丝状菌膨胀的控制策略及微生物群体感应的作用机制,综述了群体感应与群体淬灭控制丝状菌膨胀的研究进展,分析了其影响因素并提出未来研究方向,为控制丝状菌污泥膨胀提供一种新的理论思路。 展开更多
关键词 污水处理 活性污泥法 微生物 污泥膨胀 丝状菌膨胀 群体感应 群体淬灭
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控制聚丙烯膨体长丝线密度变异系数的探讨
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作者 邬杨伟 杜飓风 夏寅 《合成纤维》 CAS 2024年第8期23-25,共3页
通过优选挤压机和纺丝箱温度,观察计量泵齿轮的磨损状况,选择喷丝板使用周期,确保分丝正确,保证预牵伸辊和主牵伸辊上缠绕圈数相同,控制膨化变形长丝线密度变异系数小于1.50%,确保了膨化变形长丝连续稳定生产。
关键词 聚丙烯 膨体长丝 线密度 变异系数
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丝状真菌转录因子调控非核糖体肽合成酶介导的次级代谢产物合成研究进展
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作者 白晓轩 张极峰 +2 位作者 李婧 李奥 刘士平 《食品工业科技》 CAS 北大核心 2024年第17期445-453,共9页
丝状真菌(Filamentous fungi)产生的次级代谢产物(Secondary Metabolites,SM)广泛应用于生物医药、生物防治及食品等领域。大多数SM的生物合成与非核糖体肽合成酶(Nonribosomal peptide synthetase,NRPS)的催化密切相关,故NRPS的表达调... 丝状真菌(Filamentous fungi)产生的次级代谢产物(Secondary Metabolites,SM)广泛应用于生物医药、生物防治及食品等领域。大多数SM的生物合成与非核糖体肽合成酶(Nonribosomal peptide synthetase,NRPS)的催化密切相关,故NRPS的表达调控对SM的生物合成至关重要。为了深入了解丝状真菌NRPS基因簇的表达调控模式,本文就通路特异性和全局性两种转录因子调控丝状真菌NRPS介导SM生成的研究进展进行了综述,以期深化对丝状真菌中转录因子调控NRPS介导的SM生成机制的认识,为丝状真菌天然产物的开发提供参考依据。 展开更多
关键词 转录因子 丝状真菌 非核糖体肽合成酶(NRPS) 次级代谢产物 生物合成
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数码印花尼龙6地毯丝的制备与实践
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作者 陈自强 范红娟 +1 位作者 朱浩杰 唐震 《合成纤维》 CAS 2024年第5期41-44,共4页
以尼龙6切片为原料进行熔融纺丝及后加工,制备适用于数码印花地毯的尼龙6膨体变形丝(BCF)及其加捻定型丝。结果表明:拉伸温度为190℃,拉伸倍数为2.8倍、膨化变形温度为210℃,可生产出适用于数码印花地毯的尼龙6 BCF;定型选用饱和蒸汽定... 以尼龙6切片为原料进行熔融纺丝及后加工,制备适用于数码印花地毯的尼龙6膨体变形丝(BCF)及其加捻定型丝。结果表明:拉伸温度为190℃,拉伸倍数为2.8倍、膨化变形温度为210℃,可生产出适用于数码印花地毯的尼龙6 BCF;定型选用饱和蒸汽定型原理的定型机,定型温度设在128℃,可生产出性能符合数码印花地毯用的尼龙6加捻定型丝;用该尼龙6加捻定型丝织毯后,毯面丰满、颗粒度好、手感舒服、色泽鲜艳。 展开更多
关键词 尼龙6膨体变形丝 加捻定型 数码印花地毯 毯面条痕
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基于阻力和伴流不均匀度的21万吨散货船线型优化
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作者 程保国 郝金凤 强兆新 《中国舰船研究》 CSCD 北大核心 2024年第4期241-246,共6页
[目的]基于船体绕流场计算分析,以阻力和伴流不均匀度为优化目标,对21万吨散货船线型进行优化设计。[方法]首先,借助计算流体动力学(CFD)工具对初始线型进行数值评估并计算船体绕流场,得到波形、压力分布、速度分布等流场特征。其次,根... [目的]基于船体绕流场计算分析,以阻力和伴流不均匀度为优化目标,对21万吨散货船线型进行优化设计。[方法]首先,借助计算流体动力学(CFD)工具对初始线型进行数值评估并计算船体绕流场,得到波形、压力分布、速度分布等流场特征。其次,根据CFD计算结果,构建优化策略,形成改型方案,并对改型方案进行CFD计算,评估阻力和伴流不均匀度优化效果。最后,开展优化后船型快速性模型试验,验证优化效果。[结果]CFD计算结果表明,改型相较于原型,有效功率降低了2.46%,伴流不均匀度降低了8.48%。模型试验结果表明,改型相较于原型,螺旋桨收到功率降低了3.49%。[结论]研究显示,所提出的优化方法可以获得阻力性能优良、伴流场均匀性好的船体线型,具有较强的工程适用性。 展开更多
关键词 流场 阻力 伴流不均匀度 散货船 线型优化 计算流体动力学
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50 ft 36 t大容积内陆通用集装箱技术研究
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作者 汪正义 陆松 +1 位作者 殷涛 刘金超 《铁道货运》 2024年第11期12-17,30,共7页
为适应白货产品物流特点,满足铁路白货运输需求,开发大容积内陆集装箱作为载运器具。根据铁路限界要求和铁路主要集装箱运输车辆的装载能力,确定新型大容积通用内陆集装箱的长度为50 ft,最大总重为36 t。在满足铁路限界和铁路平车车辆... 为适应白货产品物流特点,满足铁路白货运输需求,开发大容积内陆集装箱作为载运器具。根据铁路限界要求和铁路主要集装箱运输车辆的装载能力,确定新型大容积通用内陆集装箱的长度为50 ft,最大总重为36 t。在满足铁路限界和铁路平车车辆宽度的基础上,分析集装箱横截面可采用的2种设计方案——直角矩形横截面和变截面横截面。计算2种设计方案的集装箱最大内容积,最终选择集装箱横截面为变截面梯形的设计方案。对选定的设计方案进行超限校核,计算结果表明:集装箱横截面底部矩形部分及顶部梯形部分均满足铁路限界要求。分析研究集装箱的主要结构并进行轻量化设计,在此基础上,进行有限元分析计算。该型集装箱已经开始投入使用,有效助力了铁路现代物流体系的建设。 展开更多
关键词 轻泡货物 白货 铁路运输 集装箱开发 大容积 方案比选 有限元计算
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非富勒烯有机体异质结中磁光电流及相干自旋混合理论研究进展
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作者 阚利萱 胡佳骥 王恺 《发光学报》 EI CAS CSCD 北大核心 2024年第2期215-230,共16页
有机非富勒烯分子受体,又称稠环电子受体,由于其优良的光电转换性质,现已成为备受关注的有机光电子材料之一。基于该类材料所发展的有机体异质结太阳能电池,其能量转换效率已逼近20%。而制备高效稳定的有机体异质结太阳能电池离不开对... 有机非富勒烯分子受体,又称稠环电子受体,由于其优良的光电转换性质,现已成为备受关注的有机光电子材料之一。基于该类材料所发展的有机体异质结太阳能电池,其能量转换效率已逼近20%。而制备高效稳定的有机体异质结太阳能电池离不开对材料物性和光伏过程的深入探索。在众多研究体系中,非富勒烯光伏自旋动力学的发展尚处于起步阶段,其内在的光物理机理尚未明确。而光激发磁光电流技术能通过监测有机体异质结中极化子对的解离,在器件工作状态下,原位表征光伏自旋动力学过程。本文结合实验和理论研究,科学地阐述目前主流的有机磁光电流理论基础及函数模型,如低磁场下的超精细耦合效应和自旋-轨道耦合效应,高磁场下的Δg机制;探讨不同有机体异质结在不同表征条件下如偏压、温度、光强的信号差异;最后,讨论了超快光谱技术在有机体异质结体系中的应用。 展开更多
关键词 非富勒烯受体 有机体异质结太阳能电池 电荷转移态 磁光电流 极化子对
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非测地线缠绕理论及应用研究现状
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作者 吴轶城 廖英强‧ 张弛 《航天制造技术》 2024年第1期71-78,共8页
纤维缠绕在压力容器、风力叶片等方面有着广泛的应用,其中纤维缠绕路径是影响性能的一项重要因素。非测地线缠绕的优势在于可以根据需要设计纤维轨迹,使纤维强度得到充分利用。本文对非测地线缠绕的研究现状进行了综合论述,可为优化非... 纤维缠绕在压力容器、风力叶片等方面有着广泛的应用,其中纤维缠绕路径是影响性能的一项重要因素。非测地线缠绕的优势在于可以根据需要设计纤维轨迹,使纤维强度得到充分利用。本文对非测地线缠绕的研究现状进行了综合论述,可为优化非测地线缠绕设计提供参考。 展开更多
关键词 复合材料 纤维缠绕 非测地线缠绕 滑线系数
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宁波地区长期非粮化生产对耕层土壤理化性质的影响
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作者 应虹 朱诗君 +2 位作者 金树权 汪峰 周金波 《中国农学通报》 2024年第27期75-82,共8页
本研究旨在探究宁波地区长期非粮化生产对耕层土壤理化性质的影响,为非粮化耕地的恢复利用提供参考依据。通过比较采集的全市130个非粮化耕地和53个对照样地的土壤样品,并结合地貌类型(水网平原、滨海平原、丘陵山区、河谷平原)和非粮... 本研究旨在探究宁波地区长期非粮化生产对耕层土壤理化性质的影响,为非粮化耕地的恢复利用提供参考依据。通过比较采集的全市130个非粮化耕地和53个对照样地的土壤样品,并结合地貌类型(水网平原、滨海平原、丘陵山区、河谷平原)和非粮化种植类型(苗木、果树)进行了系统分析。结果表明:非粮化耕地的土壤pH、有机质含量、土壤容重分别为5.74±0.83、24.72±8.01 g/kg和1.28±0.05 g/cm^(3),分别显著低于或高于周边水田的6.17±1.02、30.07±10.68 g/kg和1.18±0.05 g/cm^(3)(P<0.05)。不同地貌类型条件下,非粮化生产对耕层土壤理化性质的影响存在差异,其中对丘陵山区和河谷平原的耕地产生影响较大,导致土壤EC值、有机质和全氮含量均下降10%以上,土壤pH下降至酸性水平(pH<5.5)。2种非粮化生产方式(苗木和果树种植)均会不同程度导致土壤pH、EC值、CEC值、有机质和全氮含量下降与土壤容重上升,但苗木种植的影响程度均要大于果树种植,其中非粮化苗木地的有机质含量为22.90±7.18 g/kg,显著低于非粮化果园和对照样地的30.07±10.68 g/kg和26.87±8.44 g/kg(P<0.05)。研究表明,宁波地区长期非粮化生产导致土壤酸化、地力下降和土壤紧实度提高等问题,同时非粮化耕地的恢复利用应充分考虑地貌类型和非粮化种植类型等因素差异。 展开更多
关键词 宁波地区 非粮化生产 土壤理化性质 地貌 种植类型 复耕利用 土壤pH 有机质含量 土壤容重 电导率 阳离子交换量 耕地管理 土壤质量
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Effect of nitrate concentration on filamentous bulking under low level of dissolved oxygen in an airlift inner circular anoxic-aerobic incorporate reactor 被引量:2
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作者 Yiming Su Yalei Zhang +1 位作者 Xuefei Zhou Ming Jiang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第9期1736-1744,共9页
This laboratory research investigated a possible cause of filamentous bulking under low level of dissolved oxygen conditions (dissolved oxygen value in aerobic zone maintained between 0.6-0.8 mgO2 /L) in an airlift ... This laboratory research investigated a possible cause of filamentous bulking under low level of dissolved oxygen conditions (dissolved oxygen value in aerobic zone maintained between 0.6-0.8 mgO2 /L) in an airlift inner-circular anoxic-aerobic reactor. During the operating period, it was observed that low nitrate concentrations affected sludge volume index significantly. Unlike the existing hypothesis, the batch tests indicated that filamentous bacteria (mainly Thiothrix sp.) could store nitrate temporarily under carbon restricted conditions. When nitrate concentration was below 4 mg/L, low levels of carbon substrates and dissolved oxygen in the aerobic zone stimulated the nitrate-storing capacity of filaments. When filamentous bacteria riched in nitrate reached the anoxic zone, where they were exposed to high levels of carbon but limited nitrate, they underwent denitrification. However, when nonfilamentous bacteria were exposed to similar conditions, denitrification was restrained due to their intrinsic nitrate limitation. Hence, in order to avoid filamentous bulking, the nitrate concentration in the return sludge (from aerobic zone to the anoxic zone) should be above 4 mg/L, or alternatively, the nitrate load in the anoxic zone should be kept at levels above 2.7 mg NO-3N/g SS. 展开更多
关键词 anoxic-aerobic system low dissolved oxygen filamentous bulking low nitrate concentration nitrate-storing capacity
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Non-fullerene small molecule electron acceptors for high-performance organic solar cells 被引量:1
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作者 Hao Lin Qiang Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第4期990-1016,共27页
Fullerenes and their derivatives are important types of electron acceptor materials and play a vital role in organic solar cell devices. However, the fullerene acceptor material has some difficulties to overcome the i... Fullerenes and their derivatives are important types of electron acceptor materials and play a vital role in organic solar cell devices. However, the fullerene acceptor material has some difficulties to overcome the intrinsic shortcomings, such as weak absorption in the visible range, difficulty in modification and high cost, which limit the performance of the device and the large-scale application of this type of acceptors. In recent years, non-fullerene electron acceptor material has attracted the attention of scientists due to the advantages of adjustable energy level, wide absorption, simple synthesis, low processing cost and good solubility. Researchers can use the rich chemical means to design and synthesize organic small molecules and their oligomers with specific aggregation morphology and excellent optoelectronic prop- erties. Great advances in the field of synthesis, device engineering, and device physics of non-fullerene acceptors have been achieved in the last few years. At present, non-fullerene small molecules based photovoltaic devices achieve the highest efficiency more than 13% and the efficiency gap between fullerenetype and non-fullerene-type photovoltaic devices is gradually narrowing. In this review, we explore recent progress of non-fullerene small molecule electron acceptors that have been developed and led to highefficiency photovoltaic devices and put forward the prospect of development in the future. 展开更多
关键词 Organic solar cells non-fullerene Electron acceptors bulk heterojunction
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Nanomorphology in A–D–A type small molecular acceptors-based bulk heterojunction polymer solar cells 被引量:1
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作者 Delong Liu Ying Zhang Gang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第8期104-123,I0001,I0005,共22页
Recent developments in acceptor–donor–acceptor(A–D–A) type non-fullerene acceptors have led to substantial improvements in bulk-heterojunction polymer solar cells efficiency. The device performance strongly depend... Recent developments in acceptor–donor–acceptor(A–D–A) type non-fullerene acceptors have led to substantial improvements in bulk-heterojunction polymer solar cells efficiency. The device performance strongly depends on photoactive layer morphology, as the molecular packing, donor–acceptor interface and phase separation significantly affect the charge-transfer states and charge carrier dynamics. In this review, we start with a brief introduction of the techniques most effectively utilized to characterize multiphase morphology. Then, we summarize recent progress in A–D–A type acceptors, with the emphasis on understanding the molecular structure–morphology–performance relationships. Finally, an outlook on correlating morphological characteristics with photovoltage losses is presented for further improving device performance. 展开更多
关键词 Polymer solar cells bulk HETEROJUNCTION Nanomorphology non-fullerene ACCEPTOR A–D–A TYPE SMALL molecules
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5H-Fluoreno [3,2-b:6,7-b’] Dithiophene Based Non-fullerene Small Molecular Acceptors for Polymer Solar Cell Application
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作者 WU Jiansheng XIAO Shengqiang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第5期1220-1227,共8页
Two novel non-fullerene small molecule acceptors were prepared with the conjugated backbone of 5 H-fluoreno[3, 2-b:6, 7-b’] dithiophene carrying the electron deficient unit of dicyanomethylene indanone(DICTFDT) and r... Two novel non-fullerene small molecule acceptors were prepared with the conjugated backbone of 5 H-fluoreno[3, 2-b:6, 7-b’] dithiophene carrying the electron deficient unit of dicyanomethylene indanone(DICTFDT) and rhodanine(TFDTBR), respectively. The two acceptors exhibited excellent thermal stability and strong absorption in the visible region. The LUMO level is estimated to be at-3.89 eV for DICTFDT and-3.77 eV for TFDTBR. When utilized as the acceptor in bulk heterojunction polymer solar cells with the polymer donor of PBT7-Th, the optimized maximum power conversion efficiency of 5.12% and 3.95% was obtained for the device with DICTFDT and TFDTBR, respectively. The research demonstrates that 5 H-fluoreno[3, 2-b:6, 7-b’] dithiophene can be an appealing candidate for constructing small molecular electron acceptor towards efficient polymer:non-fullerene bulk heterojunction solar cells. 展开更多
关键词 polymer solar cells bulk heterojunction non-fullerene ACCEPTOR
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造纸废水活性污泥的微生物群落结构及多样性分析 被引量:1
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作者 王硕 李长波 +3 位作者 许洪祝 赵国峥 梁慧 李东彧 《微生物学杂志》 CAS CSCD 2023年第3期19-29,共11页
为探究造纸废水活性污泥中微生物群落结构多样性以及对造纸废水处理效果的影响,利用Illumina MiSeq高通量测序方法,分析在处理造纸废水过程中,同一运行阶段两个并联氧化沟内活性污泥的微生物群落与多样性组成。结果表明,系统中处理造纸... 为探究造纸废水活性污泥中微生物群落结构多样性以及对造纸废水处理效果的影响,利用Illumina MiSeq高通量测序方法,分析在处理造纸废水过程中,同一运行阶段两个并联氧化沟内活性污泥的微生物群落与多样性组成。结果表明,系统中处理造纸废水的活性污泥在同一废水条件下微生物群落结构总体稳定,优势细菌为绿弯菌门(Chloroflexi)、拟杆菌门(Bacteroidota)、变形菌门(Proteobacteria)、Myxococcota、放线菌门(Actinobacteria)、厚壁菌门(Firmicutes)等。最重要的优势细菌类群为Chloroflexi,相对丰度占比为47.67%~48.22%,远远高于其他废水中Chloroflexi的占比,其中厌氧绳菌纲(Anaerolineae)是其主要成员,占比84.39%~88.34%,可针对性地去除造纸废水中的污染物。造纸废水活性污泥样品中存在大量特殊功能菌群,其在废水中污染物尤其是木质素的去除中发挥着重要作用。 展开更多
关键词 细菌群落结构 造纸废水 活性污泥 高通量测序 污泥膨胀 丝状菌
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Simulation of bacterial flagellar phase transition by non-convex and non-local continuum modeling
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作者 Xiaoling Wang,1,a) Yongjun He,2,b) and Qingping Sun 3,c) 1) School of Mechanical Engineering,University of Science and Technology Beijing,Beijing 100083,China 2) UME-MS,ENSTA-ParisTech,Chemin de la Huni`ere,91761 Palaiseau Cedex,France 3) Department of Mechanical Engineering,The Hong Kong University of Science and Technology,Clear Water Bay,Kowloon,Hong Kong,China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第4期74-79,共6页
Bacterial flagellar filament can undergo a stress-induced polymorphic phase transition in both vitro and vivo environments.The filament has 12 different helical forms(phases) characterized by different pitch lengths a... Bacterial flagellar filament can undergo a stress-induced polymorphic phase transition in both vitro and vivo environments.The filament has 12 different helical forms(phases) characterized by different pitch lengths and helix radii.When subjected to the frictional force of flowing fluid,the filament changes between a left-handed normal phase and a right-handed semi-coiled phase via phase nucleation and growth.This paper develops non-local finite element method(FEM) to simulate the phase transition under a displacement-controlled loading condition(controlled helix-twist).The FEM formulation is based on the Ginzburg-Landau theory using a one-dimensional non-convex and non-local continuum model.To describe the processes of the phase nucleation and growth,viscosity-type kinetics is also used.The non-local FEM simulation captures the main features of the phase transition:two-phase coexistence with an interface of finite thickness,phase nucleation and phase growth with interface propagation.The non-local FEM model provides a tool to study the effects of the interfacial energy/thickness and loading conditions on the phase transition. 展开更多
关键词 polymorphic phase transition bacterial flagellar filament GINZBURG-LANDAU non-local elasticity finite element method non-convex viscoelasticity
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A new way to construct topological invariants of non-Hermitian systems with the non-Hermitian skin effect
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作者 J S Liu Y Z Han C S Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第1期119-123,共5页
The non-Hermitian skin effect breaks the conventional bulk–boundary correspondence and leads to non-Bloch topological invariants.Inspired by the fact that the topological protected zero modes are immune to perturbati... The non-Hermitian skin effect breaks the conventional bulk–boundary correspondence and leads to non-Bloch topological invariants.Inspired by the fact that the topological protected zero modes are immune to perturbations,we construct a partner of a non-Hermitian system by getting rid of the non-Hermitian skin effect.Through adjusting the imbalance hopping,we find that the existence of zero-energy boundary states still dictate the bulk topological invariants based on the band-theory framework.Two non-Hermitian Su–Schrieffer–Heeger(SSH)models are used to illuminate the ideas.Specially,we obtain the winding numbers in analytical form without the introduction of the generalized Brillouin zone.The work gives an alternative method to calculate the topological invariants of non-Hermitian systems. 展开更多
关键词 non-Hermitian skin effect Su–Schrieffer–Heeger(SSH)model bulk–boundary correspondence topological invariant
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