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The response and anti-stress mechanisms of nitrifying sludge under long-term exposure to Cd Se quantum dots

Journal of Environmental Sciences 2024年第1期135卷 174-184页

作者： Linkai Guo Lei Yang Yongxiang Ren Shen Cui Xiaotong Li Jia Wang Jun Lan Haoqi lu yuchao Wang Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Key Lab of Northwest Water Resource Environment and EcologyMinistry of EducationXi’an University of Architecture and TechnologyXi’an 710055China

The wide application of CdSe quantum dots(QDs)increases its stress risk to sewage treatment systems.This study evaluated the response of nitrification performance,floc characteristics and microbial community of nitrifying sludge under long-term exposure to CdSe QDs.Results showed CdSe QDs(≥1 mg/L)would decrease the activity of ammonia monooxygenase(AMO).Under the stress of 30 mg/L CdSe QDs,the activity of AMO was reduced by 66%,while the activities of hydroxylamine oxidase and nitrite oxidoreductase were enhanced by 19.1%and 26%,respectively.Thus,the final nitrification effects were not adversely affected,and the production rates of NO_(2)^(-)-N and NO_(3)^(-)-N were accelerated.Additionally,CdSe QDs improved biomass concentration in sludge and maintained the stability of sludge settleability.High throughput sequencing analysis showed that CdSe QDs evidently reduced the abundance and diversity of microbial community in nitrifying sludge.The abundances of amino acid metabolism and lipid metabolism were enriched.Moreover,CdSe QDs decreased the fluorescence intensity of tryptophan-like protein from 2,326 to 1,179 a.***.in loosely bound extracellular polymeric substances(EPSs)and from 3,792 to 3,117 a.***.in tightly bound EPSs.To relieve CdSe QD stress,the polysaccharide content increased from0.31 to 0.61 mg/g MLSS and intracellular antioxidant defense was activated.With CdSe QD level increasing to 30 mg/L,the total antioxygenic capacity and the activities of catalase were enhanced up to 411%and 143.2%,respectively.Thereby,CdSe QDs had little adverse effects on cell membrane integrity,microbial metabolism and the abundance of Nitrospirae.

关键词： Quantum dots Activated sludge Extracellular polymeric substances Microbial community Antioxidant effect

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Defects evolution in n-type 4H-SiC induced by electron irradiation and annealing

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Journal of Semiconductors 2024年第7期45卷 77-83页

作者： Huifan Xiong Xuesong lu Xu Gao yuchao Yan Shuai Liu Lihui Song Deren Yang Xiaodong Pi State Key Laboratory of Silicon and Advanced Semiconductor Materials&School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Key Laboratory of Power Semiconductor Materials and Devices of Zhejiang Province&Institute of Advanced Semiconductors ZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou 311200China

Radiation damage produced in 4H-SiC by electrons of different doses is presented by using multiple characterization techniques. Raman spectra results indicate that SiC crystal structures are essentially impervious to 10 Me V electron irradiation with doses up to 3000 kGy. However, irradiation indeed leads to the generation of various defects, which are evaluated through photoluminescence(PL) and deep level transient spectroscopy(DLTS). The PL spectra feature a prominent broad band centered at 500 nm, accompanied by several smaller peaks ranging from 660 to 808 nm. The intensity of each PL peak demonstrates a linear correlation with the irradiation dose, indicating a proportional increase in defect concentration during irradiation. The DLTS spectra reveal several thermally unstable and stable defects that exhibit similarities at low irradiation doses.Notably, after irradiating at the higher dose of 1000 kGy, a new stable defect labeled as R_(2)(Ec-0.51 eV) appeared after annealing at 800 K. Furthermore, the impact of irradiation-induced defects on SiC junction barrier Schottky diodes is discussed. It is observed that high-dose electron irradiation converts SiC n-epilayers to semi-insulating layers. However, subjecting the samples to a temperature of only 800 K results in a significant reduction in resistance due to the annealing out of unstable defects.

关键词： 4H-SiC deep level transient spectroscopy(DLTS) photoluminescence(PL) defects

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复杂管网中推进剂充填过程气液两相流动特性研究

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工程热物理学报 2024年第6期45卷 1763-1766页

作者：郑学波吕宇超彭佳庆骆政园白博峰长安大学能源与电气工程学院西安710064 西安航天动力研究所西安710100 西安交通大学动力工程多相流国家重点实验室西安710049

充填条件不同,充填稳定后供应管网中空气-推进剂相分布状态不同,造成供应过程不同分支流量差异。本文基于Fluent,采用VOF模型研究了充填过程气液两相流动特性,得到如下主要结论:1)环管中两股射流对撞时,管内空气体积最小,压力达到峰值;... 详细信息

充填条件不同,充填稳定后供应管网中空气-推进剂相分布状态不同,造成供应过程不同分支流量差异。本文基于Fluent,采用VOF模型研究了充填过程气液两相流动特性,得到如下主要结论:1)环管中两股射流对撞时,管内空气体积最小,压力达到峰值;随后管内流体来回震荡,空气体积、压力和入口N_(2)O_(4)流量产生波动;充填稳定后,管内空气体积基本不变,压力与入口压力相等,入口N_(2)O_(4)流量为0;2)射流与入口T形管壁面撞击、两股射流对撞过程会产生大量微小气泡,最小气泡尺寸约为17μm;3)初始压力越低或入口压力越高,峰值压力越高,达到稳定所需时间越短,稳定时管内空气体积越小。

关键词：复杂管网推进剂充填气液相分布气泡尺寸

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疾控中心三级生物安全实验室电气设计探讨

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建筑电气 2024年第1期43卷 40-43页

作者：卢宇超陈杰甫上海建筑设计研究院有限公司上海市200041

结合上海市疾病预防控制中心新建项目,论述疾控中心三级生物安全实验室概况、特点并分析其电气设计要点,包括实验室供配电设计、电气管线敷设原则、电气消防设计、工艺设备及其辅助设备(送排风机、水处理设备等)备用电源设置、自动控制... 详细信息

结合上海市疾病预防控制中心新建项目,论述疾控中心三级生物安全实验室概况、特点并分析其电气设计要点,包括实验室供配电设计、电气管线敷设原则、电气消防设计、工艺设备及其辅助设备(送排风机、水处理设备等)备用电源设置、自动控制要点等。

关键词：疾控中心设计要点三级生物安全实验室供配电管线敷设电气消防自动控制备用电源

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绿豆球蛋白淀粉样纤维的形成、结构表征及乳化特性

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食品科学 2024年第7期45卷 43-51页

作者：白露李志明张舒冯玉超富天昕刘宇航王长远黑龙江八一农垦大学食品学院黑龙江大庆163319 国家杂粮工程技术研究中心黑龙江大庆163319

基于不同酸热处理时间探讨绿豆球蛋白淀粉样纤维(mung bean globulin amyloid fibrils,MBGFs)形成过程中的结构演变规律,同时探究各阶段形成的MBGFs乳化特性。结果表明:加热0~12 h过程中,绿豆球蛋白(mung bean globulin,MBG)的亚基逐渐... 详细信息

基于不同酸热处理时间探讨绿豆球蛋白淀粉样纤维(mung bean globulin amyloid fibrils,MBGFs)形成过程中的结构演变规律,同时探究各阶段形成的MBGFs乳化特性。结果表明:加热0~12 h过程中,绿豆球蛋白(mung bean globulin,MBG)的亚基逐渐降解,水解成以小分子多肽为主的纤维结构单元;并产生大量β-折叠结构,相对含量从0 h的(18.28±0.75)%提升到12 h的(53.61±1.15)%,与硫磺素T结合后荧光强度增强;MBGFs形态逐渐变得细长、柔韧,在此过程中发生了定向的纤维化聚集;在加热16~24 h过程中,成熟的MBGFs结构逐渐发生解离,纤维结构特征被破坏;与MBG相比,MBGFs乳液的乳化活性指数、乳化稳定性指数、蛋白吸附率和界面蛋白含量均有明显提高,其中酸热处理4 h形成的MBGFs乳化效果最优;4 h MBGFs乳液油滴体积较小、分布均匀有序,表观黏度最高,具有弹性凝胶结构。综上,不同酸热处理时间对MBGFs结构和乳化特性具有显著影响,MBGFs与MBG相比具有更优异的乳化性能。本研究为明晰MBGFs形成规律提供理论支撑,为高效食品级乳化剂的研发提供思路。

关键词：绿豆球蛋白蛋白质淀粉样纤维结构表征乳化特性

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Two-step hydrothermal conversion of biomass waste to humic acid using hydrochar as intermediate

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Frontiers of Environmental Science & Engineering 2023年第10期17卷 17-26页

作者： yuchao Shao Jun Zhao Yuyang Long Wenjing lu School of Environment Tsinghua UniversityBeijing 100084China Department of Biology Institute of Bioresource and AgricultureHong Kong Baptist UniversityHong Kong 999077China Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling Instrumental Analysis CenterSchool of Environmental Science and EngineeringZhejiang Gongshang UniversityHangzhou 310012China

Converting biomass materials to humic acid is a sustainable method for humic acid production and achieve biomass valorization. A two-step hydrothermal treatment method was adopted in this study to produce humic acid from corn stalks. In the first step of the process, hydrochar was prepared at different hydrothermal temperatures and pH values. Their chemical properties were then analyzed, and the hydrochar-derived humic acids were produced under alkaline hydrothermal conditions (denoted as HHAalk). The hydrochar, prepared under high temperature (200 °C) and strong acidic (pH 0) conditions, achieved high HHAalk yields (i.e., 67.9 wt% and 68.8 wt% calculated based on weight of hydrochar). The sources of HHAalk formation were as follows: 1) production in the hydrochar preparation stage, and 2) increment under the alkaline hydrothermal treatment of hydrochar. The degree of hydrochar unsaturation was suggested as an indicator for evaluating the hydrochar humification potential under alkaline hydrothermal conditions. This study provides an important reference for the preparation of suitable hydrochar with high hydrothermal humification potential.

关键词： Biowaste Hydrochar Humic acid Hydrothermal parameter Unsaturation

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Facile fabrication of branched-chain carbohydrate chips for studying carbohydrate-protein interactions by QCM biosensor

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Chinese Chemical Letters 2018年第1期29卷 65-68页

作者： yuchao lu Siyu Song Chenxi Hou Shuang Pang Xueming Li Xiaowen Wu Chen Shao Yuxin Pei Zhichao Pei Shaanxi Key Laboratory of Natural Products & Chemical Biology College of Chemistry and Pharmacy Northwest A & F University Attana

A novel approach for fabricating branched-chain （BC） carbohydrate chips to study carbohydrate-protein interactions using Quartz Crystal Microbalance （QCM） biosensor was developed. This approach utilizes functional alkynyl-branch molecule modified chip surfaces, which through the terminal alkynyl group for covalent linking of unprotected azide-carbohydrates. The unprotected azide-carbohydrates were syhthesized in one-step using 2-azido-l,B-dimethylqmidazolinium as catalyst, avoiding complex chemical modifications. Additionally, the branch surface modified with the carbohydrates not only supplies more specific binding site but also reveals significant cluster effect. To exemplify the sugar cluster effect on BC carbohydrate chips, BC Galactose and Mannose chips prepared in this work were used to determine carbohydrate-lectin interactions using QCM biosensor. The results clearly showed that BC chip significantly improves the detection sensitivity compared with the straight-chain （SC） chip. More importantly, the BC galactose chip sensitivity was enhanced 40% compared with the SC galactose chip.

关键词： MultivalentBrach carbohydrate chipO CMCarbohydrate-protein interactions

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NR4A1通过IκBα/NF-κB通路调控过氧化氢诱导人脐静脉内皮细胞凋亡的机制

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山东大学学报（医学版） 2024年第3期62卷 11-19页

作者：姜子晗芦兴晨孙露赵蕙琛左丹马小莉刘元涛张玉超青岛大学附属青岛临床医学院青岛市市立医院山东青岛266011 山东大学齐鲁医院(青岛)临床营养科山东青岛266011 青岛市市立医院内分泌科山东青岛266011 青岛市市立医院医学杂志编辑部山东青岛266011 山东大学齐鲁医院(青岛)内分泌科山东青岛266011

目的探讨过氧化氢(H_(2)O_(2))诱导的人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)氧化应激中孤核受体NR4A1表达变化,以及其对细胞凋亡的影响及机制。方法使用不同浓度及时间梯度H_(2)O_(2)处理HUVECs,采用CCK-8... 详细信息

目的探讨过氧化氢(H_(2)O_(2))诱导的人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)氧化应激中孤核受体NR4A1表达变化,以及其对细胞凋亡的影响及机制。方法使用不同浓度及时间梯度H_(2)O_(2)处理HUVECs,采用CCK-8法检测细胞活性,TUNEL法检测细胞凋亡,Western blotting法检测Bcl-2、Bax与NR4A1蛋白表达;采用siRNA转染建立敲低NR4A1与对照的HUVECs,分为si-NC组及si-NR4A1组,H_(2)O_(2)处理后检测各组细胞抑凋亡蛋白Bcl-2、凋亡蛋白Bax表达,TUNEL法检测细胞凋亡;采用慢病毒感染建立稳定过表达NR4A1与对照的HUVECs,并进行H_(2)O_(2)处理,分为空载对照组(NC组)、过表达组(OV组)、NC+H_(2)O_(2)组及OV+H_(2)O_(2)组。TUNEL法检测各组细胞凋亡、Western blotting法检测各组中NR4A1、Bcl-2、Bax、总IκBα的蛋白表达、P65蛋白在细胞核/质定位。结果200μmol/L H_(2)O_(2)处理细胞6 h,HUVECs活力显著下降,凋亡水平显著上升,Bax/Bcl-2比值升高(P<0.001);NR4A1蛋白表达量增加;与si-NC组相比,si-NR4A1组在H_(2)O_(2)处理后细胞凋亡率、Bax/Bcl-2比值下降(P<0.001);OV+H_(2)O_(2)组细胞凋亡率、Bax/Bcl-2比值较NC+H_(2)O_(2)组显著降低(P<0.001);相较于NC+H_(2)O_(2)组,P65蛋白在OV+H_(2)O_(2)组中细胞核内表达显著降低(P<0.05),细胞质内表达显著上调(P<0.001);与NC+H_(2)O_(2)组相比,OV+H_(2)O_(2)组总IκBα表达上调(P<0.001)。结论H_(2)O_(2)诱导HUVECs发生细胞凋亡;HUVECs内NR4A1蛋白过表达可抑制细胞凋亡,其作用机制可能与调控IκBα的表达与抑制NF-κB的核转位有关。

关键词：孤核受体NR4A1 人脐静脉内皮细胞 IκBα蛋白 NF-κB核转位细胞凋亡

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不同干燥方式对青海蕨麻品质特性的影响

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农产品加工 2024年第4期 43-48,54页

作者：周先加毛海峰鲁瑶刘毓超青海省轻工业研究所有限责任公司青海西宁810001

以5种不同干燥方式(热风干燥、热泵干燥、碳纤维远红外、碳纤维远红外联合热泵干燥及真空脉动干燥)后的青海蕨麻为研究对象,通过比较干燥时间、设备能耗,以及干制蕨麻的感官品质(色度、感官评分、复水比)、营养品质(维C、多糖、蛋白质... 详细信息

以5种不同干燥方式(热风干燥、热泵干燥、碳纤维远红外、碳纤维远红外联合热泵干燥及真空脉动干燥)后的青海蕨麻为研究对象,通过比较干燥时间、设备能耗,以及干制蕨麻的感官品质(色度、感官评分、复水比)、营养品质(维C、多糖、蛋白质、氨基酸)、食用品质(电子舌、质构特性),结合主成分综合评价方法确定最适宜的干燥方式。结果表明,热泵干燥和联合干燥技术的能耗低,热风干燥技术蕨麻感官评分最高为73.50分,真空脉动干燥的复水比最低为1.02,联合干燥技术蕨麻色泽最亮,热风干燥总氨基酸含量最高为9.05 g/100 g,联合干燥维C含量最高为9.42 g/100 g。各干燥技术蛋白质、多糖和味觉特征差异不明显,干燥蕨麻品质主成分综合评价结果为热风干燥技术最佳,可引进此技术干燥青海蕨麻。研究结果可为青海地区蕨麻引进干燥技术提供科学依据。

关键词：不同干燥方式青海蕨麻感官评价营养指标品质特性

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Derivation and validation of a similarity law for free-flight wind tunnel tests of parallel stage separation

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Chinese Journal of Aeronautics 2023年第8期36卷 91-100页

作者： Zhiming CHEN Fei XUE Haichuan YU yuchao WANG Zenghui JIANG Wei lu Lei DONG China Academy of Aerospace Aerodynamics Beijing 100074China Beijing Institute of Astronautical Systems Engineering Beijing 100076China China Academy of Launch Vehicle Technology Beijing 100076China

Aiming at the safety problem of the stage separation of parallel reusable high-speed air vehicles,this paper studies the unsteady test method and focuses on deriving a similarity law of parallel stage separation free-flight wind tunnel tests.The new similarity law considers the influences of aerodynamic force and gravity on the motions of the two stages,as well as the influence of aerodynamic interference between the two stages on each other’s motion.From the perspective of multiangle physical equations,the conditions to ensure that the two-stage separation trajectory of a wind tunnel test is similar to that of a real air vehicle are derived innovatively,so as to ensure the authenticity and credibility of wind tunnel test results.The similarity law is verified by an HIFiRE-5 air vehicle,and the separation trajectories of wind tunnel tests and the real air vehicle are obtained by numerical simulation.The research shows that the similarity law derived in this paper can ensure that wind tunnel free-flight tests have the ability to predict the two-stage separation characteristics of real parallel vehicles.By analyzing the separation trajectory curve of the typical state,it is found that the new method can ensure that the trajectory error of a wind tunnel test does not exceed 1%,which indicates that this method is credible.The establishment of the new method lays the foundation for subsequent wind tunnel tests and provides support for research on the safety of the stage separation of parallel reusable air vehicles.

关键词： Droptesting in wind tunnel Free-flight wind tunnel test Multi-body separation Parallel stage separation Similaritylaw

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