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Comprehensive analysis of the gut microbiome and posttranslational modifications elucidates the route involved in microbiota-host interactions 被引量:1
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作者 Hai-Yang Wang Lan-Xiang Liu +8 位作者 Xue-Yi Chen Yang-Dong Zhang Wen-Xia Li Wen-Wen Li Lian Wang Xiao-Long Mo Hong Wei Ping Ji Peng Xie 《Zoological Research》 SCIE CSCD 2024年第1期95-107,共13页
The gut microbiome interacts with the host to maintain body homeostasis,with gut microbial dysbiosis implicated in many diseases.However,the underlying mechanisms of gut microbe regulation of host behavior and brain f... The gut microbiome interacts with the host to maintain body homeostasis,with gut microbial dysbiosis implicated in many diseases.However,the underlying mechanisms of gut microbe regulation of host behavior and brain functions remain unclear.This study aimed to elucidate the influence of gut microbiota on brain functions via post-translational modification mechanisms in the presence or absence of bacteria without any stimulation.We conducted succinylome analysis of hippocampal proteins in germ-free(GF)and specific pathogen-free(SPF)mice and metagenomic analysis of feces from SPF mice.These results were integrated with previously reported hippocampal acetylome and phosphorylome data from the same batch of mice.Subsequent bioinformatics analyses revealed 584 succinylation sites on 455 proteins,including 54 up-regulated succinylation sites on 91 proteins and 99 down-regulated sites on 51 proteins in the GF mice compared to the SPF mice.We constructed a panoramic map of gut microbiota-regulated succinylation,acetylation,and phosphorylation,and identified cross-talk and relative independence between the different types of post-translational modifications in modulating complicated intracellular pathways.Pearson correlation analysis indicated that 13 taxa,predominantly belonging to the Bacteroidetes phylum,were correlated with the biological functions of post-translational modifications.Positive correlations between these taxa and succinylation and negative correlations between these taxa and acetylation were identified in the modulation of intracellular pathways.This study highlights the hippocampal physiological changes induced by the absence of gut microbiota,and proteomic quantification of succinylation,phosphorylation,and acetylation,contributing to our understanding of the role of the gut microbiome in brain function and behavioral phenotypes. 展开更多
关键词 Gut microbiota Hippocampal protein Post-translational modifications SUCCINYLATION ACETYLATION PHOSPHORYLATION
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Implications of electrode modifications in aqueous organic redox flow batteries
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作者 Zahid Manzoor Bhat Mohammad Furquan +3 位作者 Muhammad Aurang Zeb Gul Sial Umair Alam Atif Saeed Alzahrani Mohammad Qamar 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期499-510,I0011,共13页
Aqueous organic redox flow batteries(RFBs)exhibit favorable characteristics,such as tunability,multielectron transfer capability,and stability of the redox active molecules utilized as anolytes and catholytes,making t... Aqueous organic redox flow batteries(RFBs)exhibit favorable characteristics,such as tunability,multielectron transfer capability,and stability of the redox active molecules utilized as anolytes and catholytes,making them very viable contenders for large-scale grid storage applications.Considerable attention has been paid on the development of efficient redox-active molecules and their performance optimization through chemical substitutions at various places on the backbone as part of the pursuit for high-performance RFBs.Despite the fact that electrodes are vital to optimal performance,they have not garnered significant attention.Limited research has been conducted on the effects of electrode modifications to improve the performance of RFBs.The primary emphasis has been given on the impact of electrode engineering to augment the efficiency of aqueous organic RFBs.An overview of electron transfer at the electrode-electrolyte interface is provided.The implications of electrode modification on the performance of redox flow batteries,with a particular focus on the anodic and cathodic half-cells separately,are then discussed.In each section,significant discrepancies surrounding the effects of electrode engineering are thoroughly examined and discussed.Finally,we have presented a comprehensive assessment along with our perspectives on the future trajectory. 展开更多
关键词 Redox flow batteries Electrode modification Organic redox molecules Outer sphere and inner sphere
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Stem cell-based ischemic stroke therapy:Novel modifications and clinical challenges
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作者 Yuankai Sun Xinchi Jiang Jianqing Gao 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2024年第1期18-34,共17页
Ischemic stroke(IS)causes severe disability and high mortality worldwide.Stem cell(SC)therapy exhibits unique therapeutic potential for IS that differs from current treatments.SC’s cell homing,differentiation and par... Ischemic stroke(IS)causes severe disability and high mortality worldwide.Stem cell(SC)therapy exhibits unique therapeutic potential for IS that differs from current treatments.SC’s cell homing,differentiation and paracrine abilities give hope for neuroprotection.Recent studies on SC modification have enhanced therapeutic effects for IS,including gene transfection,nanoparticle modification,biomaterial modification and pretreatment.Thesemethods improve survival rate,homing,neural differentiation,and paracrine abilities in ischemic areas.However,many problems must be resolved before SC therapy can be clinically applied.These issues include production quality and quantity,stability during transportation and storage,as well as usage regulations.Herein,we reviewed the brief pathogenesis of IS,the“multi-mechanism”advantages of SCs for treating IS,various SC modification methods,and SC therapy challenges.We aim to uncover the potential and overcome the challenges of using SCs for treating IS and convey innovative ideas for modifying SCs. 展开更多
关键词 Ischemic stroke Stem cell therapy Stem cell modification Cell therapy challenge
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Variations of Atmospheric ELF/VLF Radio Noise Due to Seismogenic Modifications in Tropospheric Conductivity
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作者 Masashi Hayakawa Alexander P. Nickolaenko 《Open Journal of Earthquake Research》 2024年第2期113-132,共20页
We suggest a possible explanation of the influence of pre-seismic activity on the registration rate of natural ELF(extremely low frequency)/VLF(very low frequency) pulses and the changes of their characteristics. The ... We suggest a possible explanation of the influence of pre-seismic activity on the registration rate of natural ELF(extremely low frequency)/VLF(very low frequency) pulses and the changes of their characteristics. The main idea is as follows. The distribution of the electric field around a thundercloud depends on the conductivity profile of the atmosphere. Quasi-static electric fields of a thundercloud decrease in those tropospheric regions where an increase of air conductivity is generated by pre-seismic activities due to emanation of radioactive gas and water into the lower atmosphere. The electric field becomes reduced in the lower troposphere, and the probability decreases of the cloud-to-ground (CG) strokes in such “contaminated” areas. Simultaneously, the electric field grows inside and above the thunderclouds, and hence, we anticipate a growth in the number of horizontal and tilted inter-cloud (or intra-cloud) (both termed as IC discharges) strokes. Spatial orientation of lightning strokes reduces vertical projection of their individual amplitudes, while the rate (median number strokes per a unit time) of discharges grows. We demonstrate that channel tilt of strokes modifies the spectral content of ELF/VLF radio noise and changes the rate of detected pulses during the earthquake preparation phase. 展开更多
关键词 ELF/VLF Radio Noise Earthquake Precursor Pre-Seismic Modification Conductivity Anomaly in the Lower Atmosphere Radioactive Radon Gases CG Lightning Discharges IC Discharges Cloud-to-Ionosphere Discharge
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Epigenetic modifications and metabolic memory in diabetic retinopathy:beyond the surface 被引量:1
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作者 Dan-Dan Liu Chao-Yang Zhang +3 位作者 Jing-Ting Zhang Li-Min Gu Guo-Tong Xu Jing-Fa Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第7期1441-1449,共9页
Epigenetics focuses on DNA methylation,histone modification,chromatin remodeling,noncoding RNAs,and other gene regulation mechanisms beyond the DNA sequence.In the past decade,epigenetic modifications have drawn more ... Epigenetics focuses on DNA methylation,histone modification,chromatin remodeling,noncoding RNAs,and other gene regulation mechanisms beyond the DNA sequence.In the past decade,epigenetic modifications have drawn more attention as they participate in the development and progression of diabetic retinopathy despite tight control of glucose levels.The underlying mechanisms of epigenetic modifications in diabetic retinopathy still urgently need to be elucidated.The diabetic condition facilitates epigenetic changes and influences target gene expression.In this review,we summarize the involvement of epigenetic modifications and metabolic memory in the development and progression of diabetic retinopathy and propose novel insights into the treatment of diabetic retinopathy. 展开更多
关键词 diabetic retinopathy DNA methylation EPIGENETICS histone modification metabolic memory M6A modification non-coding RNAs REVIEW
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Current Strategies of Surface Modifications to Polyurethane Biomaterials for Vascular Grafts
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作者 Huai-Gu Huang Tao Xiang Yue-Xin Chen 《Chinese Medical Sciences Journal》 CAS CSCD 2023年第4期279-285,共7页
As the number of patients suffering from cardiovascular diseases and peripheral vascular diseases rises,the constraints of autologous transplantation remain unavoidable.As a result,artificial vascular grafts must be d... As the number of patients suffering from cardiovascular diseases and peripheral vascular diseases rises,the constraints of autologous transplantation remain unavoidable.As a result,artificial vascular grafts must be developed.Adhesion of proteins,platelets and bacteria on implants can result in stenosis,thrombus formation,and postoperative infection,which can be fatal for an implantation.Polyurethane,as a commonly used biomaterial,has been modified in various ways to deal with the adhesions of proteins,platelets,and bacteria and to stimulate endothelium adhesion.In this review,we briefly summarize the mechanisms behind adhesions,overview the current strategies of surface modifications of polyurethane biomaterials used in vascular grafts,and highlight the challenges that need to be addressed in future studies,aiming to gain a more profound understanding of how to develop artificial polyurethane vascular grafts with an enhanced implantation success rate and reduced side effect. 展开更多
关键词 surface modification POLYURETHANE vascular graft ADHESION
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Compared discharge characteristics and film modifications of atmospheric pressure plasma jets with two different electrode geometries
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作者 陈雄 王兴权 +2 位作者 张彬祥 袁明 杨思泽 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期537-544,共8页
Atmospheric pressure plasma jet shows great potential for polymer film processing. The electrode geometry is the key factor to determine discharge characteristics and film modification of jets. In this paper, we compa... Atmospheric pressure plasma jet shows great potential for polymer film processing. The electrode geometry is the key factor to determine discharge characteristics and film modification of jets. In this paper, we compared the discharge characteristics and the film modifications of atmospheric pressure plasma jets with needle-ring electrode(NRE) and doublering electrode(DRE). The results show that jet with NRE has stronger electric field intensity and higher discharge power,making it present more reactive oxygen particles and higher electron temperature, but its discharge stability is insufficient.In contrast, the jet with DRE has uniform electric field distribution of lower field intensity, which allows it to maintain stable discharge over a wide range of applied voltages. Besides, the modification results show that the treatment efficiency of PET film by NRE is higher than that by DRE. These results provide a suitable atmospheric pressure plasma jets device selection scheme for polymer film processing process. 展开更多
关键词 atmospheric pressure plasma jet electrode structure jet characteristics MODIFICATION
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Successful lifestyle modifications may underlie umbilical cordmesenchymal stromal cell effects in type 2 diabetes mellitus
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作者 Alexandra Papadopoulou Konstantinos I Papadopoulos 《World Journal of Diabetes》 SCIE 2023年第3期347-351,共5页
Type 2 diabetes mellitus(T2DM)is a lifelong condition and a grave threat to human health.Innovative efforts to relieve its detrimental effects are acutely needed.The sine qua non in T2DM management is consistent adher... Type 2 diabetes mellitus(T2DM)is a lifelong condition and a grave threat to human health.Innovative efforts to relieve its detrimental effects are acutely needed.The sine qua non in T2DM management is consistent adherence to a prudent lifestyle and nutrition,combined with aerobic and resistance exercise regimens,together repeatedly shown to lead to complete reversal and even longterm remission.Non-adherence to the above lifestyle adjustments condemns any treatment effort and ultimately the patient to a grim fate.It is thus imperative that every study evaluating the effects of innovative interventions in T2DM objectively compares the novel treatment modality to lifestyle modifications,preferably through double-blind controlled randomization,before claiming efficacy. 展开更多
关键词 Type 1 diabetes mellitus Type 2 diabetes mellitus Human umbilical cord mesenchymal stem cells Diabetes remission Diabetes reversal Lifestyle modifications
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Peanut proteins:Extraction,modifications,and applications:A comprehensive review
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作者 Song Cui David Julian McClements +7 位作者 Xingfeng Xu Bo Jiao Liyang Zhou Hualu Zhou Liu Xiong Qiang Wang Qingjie Sun Lei Dai 《Grain & Oil Science and Technology》 CAS 2023年第3期135-147,共13页
As naturally sourced proteins,peanut proteins have garnered significant attention from the food industry,owing to their numerous advantages,such as easy extraction,non-pungency,and high bioavailability.Furthermore,pea... As naturally sourced proteins,peanut proteins have garnered significant attention from the food industry,owing to their numerous advantages,such as easy extraction,non-pungency,and high bioavailability.Furthermore,peanut proteins are highly digestible in the gastrointestinal tract and boast a high net protein utilization rate,making them an appealing protein source in food products and a promising alternative to animal protein.In this paper,the recent works on the extraction method,modification method,and application of peanut proteins were reviewed.Both advantages and disadvantages of current extraction and modification were discussed.Recently updated information about peanut protein research was summarized.Based on these,the prospection of peanut proteins research was presented,which may be instructive for future research in this field.Future research is still needed for accessible modification methods to develop the functional properties of peanut proteins. 展开更多
关键词 Peanut protein COMPOSITION Extraction methods modifications Applications Plant-based foods
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Redox and metabolic regulation of epigenetic modifications:an emerging toxic action mechanism
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作者 Wan-Qian Guo Wu-Sheng Xiao Wei-Dong Hao 《Toxicology Advances》 2023年第3期1-12,共12页
Epigenetic modifications modulate conformational structure of chromatin and consequently gene expression by enzyme-mediated chemical modifications of DNA and histones.The activities of epigenetic modifying enzymes dep... Epigenetic modifications modulate conformational structure of chromatin and consequently gene expression by enzyme-mediated chemical modifications of DNA and histones.The activities of epigenetic modifying enzymes depend on many co-substrates and cofactors,such as 2-oxoglutarate(2-OG),iron,S-adenosylmethionine(SAM),nicotinamide adenine dinucleotide(NAD+),flavin adenine dinucleotide(FAD),and acetyl-CoA.These factors are inter-connecting molecules that integrate cellular nutrient metabolism and redox homeostasis,two key regulators of cell proliferation,cell survival,and cell functions.Dysregulation of such delicate regulatory network has been implicated in many pathological conditions and also been increasingly recognized as an emerging mechanism responsible for environmental pollutant-induced adverse effects.In this review,we first summarize DNA and histone modifying enzymes and their essential factors,then discuss the metabolic sources and the redox regulatory roles of these enzymatic factors,and finally elaborate the mechanisms of how targeting such factors by environmental pollutants influences epigenetic regulation and perturbs cellular functions. 展开更多
关键词 epigenetic modifications redox state cellular metabolism
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CTAB改性Cu-BTC材料的合成及其吸附分离二甲苯异构体的性能 被引量:1
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作者 陈乐 种海玲 +2 位作者 张致慧 何明阳 陈群 《化工进展》 EI CAS CSCD 北大核心 2024年第1期455-464,共10页
通过水热法合成Cu-BTC晶体的过程中添加十六烷基三甲基溴化铵(CTAB),通过调节CTAB的添加量对吸附材料的形貌和孔结构进行改性,改性后的Cu-BTC材料与原Cu-BTC相比,其对对二甲苯(PX)的静态吸附量明显提高,且高于间二甲苯(MX)和邻二甲苯(O... 通过水热法合成Cu-BTC晶体的过程中添加十六烷基三甲基溴化铵(CTAB),通过调节CTAB的添加量对吸附材料的形貌和孔结构进行改性,改性后的Cu-BTC材料与原Cu-BTC相比,其对对二甲苯(PX)的静态吸附量明显提高,且高于间二甲苯(MX)和邻二甲苯(OX),从而提高了异构体的吸附选择性。研究了二甲苯异构体在Cu-BTC-CTAB材料上的静态吸附性能和吸附动力学性能。在298K、318K和338K温度下进行了一系列二甲苯有机蒸气吸附平衡实验,得到了静态吸附速率曲线和吸附等温线。改性材料中CTAB添加量为0.08%的Cu-BTC-CTAB样品对PX的吸附量和选择性最优。动力学研究表明,二甲苯异构体在Cu-BTC-CTAB上的吸附过程可以用一级动力学模型来描述。 展开更多
关键词 Cu-BTC CTAB改性 吸附分离 二甲苯异构体
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畜禽动物油甘油二酯的酶法制备及应用研究进展 被引量:1
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作者 祝超智 郭旗 +5 位作者 赵泽鑫 王卫飞 崔文明 许龙 赵改名 李航 《食品科学》 EI CAS CSCD 北大核心 2024年第3期266-274,共9页
1,3-甘油二酯(diacylglycerol,DAG)是公认的安全食品,在人体中的代谢途径不同于甘油三酯,具有提高人体新陈代谢水平以及预防肥胖和心血管疾病等功效。然而,天然DAG在食用油中的质量分数不及10%,因此,近年来高纯度DAG的制备受到了广泛关... 1,3-甘油二酯(diacylglycerol,DAG)是公认的安全食品,在人体中的代谢途径不同于甘油三酯,具有提高人体新陈代谢水平以及预防肥胖和心血管疾病等功效。然而,天然DAG在食用油中的质量分数不及10%,因此,近年来高纯度DAG的制备受到了广泛关注。与化学法相比,酶法因绿色、安全、选择性高等优点成为了油脂工业制备DAG的首选。畜禽动物油具有特殊的风味和一定的营养价值,但其高饱和脂肪、高胆固醇和高熔点等理化特征致使其在食品工业的利用受到了极大限制。鉴于此,合成畜禽动物油DAG成为了实现畜禽动物油高值化利用的一种有效途径。本文综述了酶法制备畜禽动物油DAG的研究现状及其潜在的应用价值,以期为畜禽动物油DAG的酶法加工及高值化利用提供一定的思路。 展开更多
关键词 畜禽动物油 酶法改性 甘油三酯 甘油二酯 脂肪酶
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氢氧化钠改性生物炭/凹凸棒石复合材料对铅、镉的吸附机理研究 被引量:2
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作者 郭淼 李贝贝 +2 位作者 许琳玥 张亚平 何跃 《生态与农村环境学报》 CSCD 北大核心 2024年第1期119-129,共11页
利用水稻秸秆与凹凸棒石在缺氧条件下热解制备稻秆生物炭/凹凸棒石复合材料(BA),并通过氢氧化钠改性提升其吸附性能。通过吸附动力学、等温吸附及改变初始pH等吸附试验研究复合材料在Cd、Pb一元及二元污染体系中的吸附行为,并结合扫描... 利用水稻秸秆与凹凸棒石在缺氧条件下热解制备稻秆生物炭/凹凸棒石复合材料(BA),并通过氢氧化钠改性提升其吸附性能。通过吸附动力学、等温吸附及改变初始pH等吸附试验研究复合材料在Cd、Pb一元及二元污染体系中的吸附行为,并结合扫描电镜能谱(SEM-EDS)、比表面积及孔径分析(BET)、傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)及X射线光电子能谱分析(XPS)等表征手段深入分析改性后复合材料对溶液中重金属Cd、Pb的吸附机理。试验结果表明氢氧化钠改性复合材料(NBA)对Cd^(2+)和Pb^(2+)的吸附容量分别为117.05和274.65 mg·g^(-1),其去除效率比BA分别增加31.2%和51.7%。在二元金属体系中NBA吸附能力也明显优于BA,准二级动力学模型和Langmuir等温模型能更好地用于模拟吸附结果,表明该吸附主要为单分子化学吸附过程。此外,竞争吸附分析表明在Cd、Pb共存溶液中,与Cd^(2+)相比,Pb^(2+)更易被复合材料吸附。通过SEM-EDS、FTIR、XRD和XPS等表征方法确定了NBA对Cd^(2+)和Pb^(2+)的吸附机制,主要包括其与表面含氧官能团的络合作用、与矿物质的沉淀作用及π-电子作用。综上,改性复合材料NBA在实际废水处理中是一种极具潜力的吸附剂。 展开更多
关键词 生物炭 凹凸棒石 重金属 改性 机理
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漆酶催化没食子酸染色阳离子改性棉织物的性能 被引量:1
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作者 韩雪 韩冬 +2 位作者 于乐 董爱学 王润博 《印染》 CAS 北大核心 2024年第3期20-23,共4页
利用漆酶催化没食子酸,并对聚二甲基二烯丙基氯化铵改性棉织物进行染色。结果表明:漆酶可催化没食子酸聚合,采用一浴一步法和一浴二步法工艺对改性棉织物染色,二者的染色特征值相接近,染色改性棉织物的UPF≥40,亲水性能明显提升,力学性... 利用漆酶催化没食子酸,并对聚二甲基二烯丙基氯化铵改性棉织物进行染色。结果表明:漆酶可催化没食子酸聚合,采用一浴一步法和一浴二步法工艺对改性棉织物染色,二者的染色特征值相接近,染色改性棉织物的UPF≥40,亲水性能明显提升,力学性能也有所改善。 展开更多
关键词 染色 漆酶 没食子酸 阳离子改性 棉织物
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生物炭基光催化剂改性制备及其去除水中抗生素的研究进展 被引量:1
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作者 李兵 余俊新 +2 位作者 李哲璇 董志颖 胡甜甜 《宁波大学学报(理工版)》 2024年第1期100-111,共12页
水体中抗生素会影响微生物群落结构和功能,导致生态失衡;同时,抗生素会通过食物链的富集和传递进一步污染水质,对生态环境和人类健康造成持续性危害.光催化技术因其高效且环保的特性成为众多抗生素去除技术中的重点研究对象.虽然半导体... 水体中抗生素会影响微生物群落结构和功能,导致生态失衡;同时,抗生素会通过食物链的富集和传递进一步污染水质,对生态环境和人类健康造成持续性危害.光催化技术因其高效且环保的特性成为众多抗生素去除技术中的重点研究对象.虽然半导体是光催化技术的核心材料之一,但其自身限制导致工作效率不高.生物炭(BC)作为碳家族成员之一有着众多优良特性,将生物炭与半导体复合制备的生物炭基光催化剂(BSPs)综合了两者的优越性能,有着广阔的应用前景.本文通过文献查阅,系统分析了BSPs的研究进展,涵盖BSPs的制备和改性方式,以及去除抗生素的原理和各种影响因素,并阐明其高导电性、高比表面积、强氧化性、稳定性和可回收性等特点,说明BSPs能够处理各种介质中存在的多种污染物.此外,对BSPs的局限性进行了分析,对未来研究方向提出了建议. 展开更多
关键词 抗生素 生物炭 半导体 光催化 制备 改性
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基于两性离子的纳滤膜抗污染改性方法研究进展 被引量:1
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作者 尹萌萌 王禹翰 +3 位作者 张坤 王冠 徐维国 王波 《工业水处理》 CAS CSCD 北大核心 2024年第3期37-44,共8页
纳滤膜对水中污染物的分离截留性能优异,膜污染控制和抗污染强化是该技术发展的研究热点。纳滤膜改性是强化纳滤膜抗污染性能的方法之一,基于两性离子材料的改性纳滤膜凭借两性离子材料静电作用与水分子结合的特性,在渗透性和抗污性方... 纳滤膜对水中污染物的分离截留性能优异,膜污染控制和抗污染强化是该技术发展的研究热点。纳滤膜改性是强化纳滤膜抗污染性能的方法之一,基于两性离子材料的改性纳滤膜凭借两性离子材料静电作用与水分子结合的特性,在渗透性和抗污性方面表现优秀。系统综述了强化抗污染的两性离子纳滤膜的改性方法,包括涂覆法、接枝法、界面聚合法、自组装和共混掺杂法等,并阐释了各方法所制备纳滤膜的抗污效能和适用条件,最后对各改性方法做出了展望,以期为两性离子材料在纳滤膜改性和实际应用中的研究提供参考。 展开更多
关键词 纳滤膜 改性 两性离子 膜污染
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基于联合静动力修正的混凝土斜拉桥主梁挠度变化规律研究 被引量:2
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作者 李琦 齐东春 +1 位作者 杨虎 赵志国 《中外公路》 2024年第1期111-118,共8页
针对混凝土斜拉桥服役期间主梁不断下挠的问题,该文基于修正模型分析大跨度混凝土斜拉桥服役期间主梁挠度变化规律。采用联合静动力的有限元模型修正方法,构造双目标优化问题,基于非支配排序遗传算法(NSGA-Ⅱ)求解,得到Pareto最优解集,... 针对混凝土斜拉桥服役期间主梁不断下挠的问题,该文基于修正模型分析大跨度混凝土斜拉桥服役期间主梁挠度变化规律。采用联合静动力的有限元模型修正方法,构造双目标优化问题,基于非支配排序遗传算法(NSGA-Ⅱ)求解,得到Pareto最优解集,从Pareto最优解集中找到协调最优解,从而实现有限元模型修正。模型修正后的静力位移和自振频率计算值与实测值吻合较好,能更好地反映结构的实际工作状态。在此基础上,结合主梁线形历年监测数据,分析不同徐变模式及拉索松弛效应等时变因素对主梁线形的影响,分析结果表明:采用CEB-FIP 2010徐变模式计算的挠度与实测挠度更加接近。中跨跨中下挠量最大,服役20年下挠量约为270 mm;主梁跨中挠度前5年平均增长率达33 mm/年,前5年挠度约占前40年的50%,后期主梁下挠趋于平缓。 展开更多
关键词 桥梁工程 斜拉桥 模型修正 主梁挠度
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超声改性对淀粉理化性质的影响及其在食品中的应用研究进展
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作者 石彦国 谢文健 +5 位作者 郑欣茹 陈凤莲 王艳 孙冰玉 张娜 刘琳琳 《食品安全质量检测学报》 CAS 2024年第2期1-10,共10页
淀粉是人类饮食中重要的能量来源之一,也是食品工业中重要的原材料。天然淀粉易受外界环境影响,如温度、pH、剪切力等,加工不稳定,限制了淀粉在食品领域中的应用。因此,需要对淀粉进行改性以提高淀粉的功能性,淀粉常采用物理、化学和酶... 淀粉是人类饮食中重要的能量来源之一,也是食品工业中重要的原材料。天然淀粉易受外界环境影响,如温度、pH、剪切力等,加工不稳定,限制了淀粉在食品领域中的应用。因此,需要对淀粉进行改性以提高淀粉的功能性,淀粉常采用物理、化学和酶法改性。近年来,消费者对绿色健康食品的需求增大,研究者正在寻找一种安全、环保、高效的方法。超声改性淀粉具有绿色环保、处理简单、高效安全等优点,是一种很有潜力的物理改性方法,近年来成为了研究热点。采用超声改性淀粉的实验研究很多,但关于超声改性对淀粉影响的相关性综述较少,因此,本文综述了近年来有关超声改性淀粉的研究进展,主要阐述超声改性机制及超声对淀粉颗粒结构、糊化特性、流变特性、透明度的影响,讨论了超声与其他方法复合改性对淀粉理化性质的影响,对其在食品中的应用进展进行综述,为拓展改性淀粉深加工在食品领域中的应用提供理论依据。 展开更多
关键词 超声改性 淀粉 理化性质
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超高压协同TG酶改性蛋清蛋白热诱导凝胶机理
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作者 张根生 李琪 +2 位作者 黄昕钰 杜一男 费英敏 《食品工业科技》 CAS 北大核心 2024年第14期81-88,共8页
为提高蛋清蛋白凝胶性,本研究以蛋清蛋白(Egg white protein,EWP)为研究对象,通过分析质构、持水率、分子作用力、傅里叶红外色谱、圆二色谱、粒径、电位、巯基含量、表面疏水力及扫描电镜的变化,探究超高压处理(Ultra-high pressure,U... 为提高蛋清蛋白凝胶性,本研究以蛋清蛋白(Egg white protein,EWP)为研究对象,通过分析质构、持水率、分子作用力、傅里叶红外色谱、圆二色谱、粒径、电位、巯基含量、表面疏水力及扫描电镜的变化,探究超高压处理(Ultra-high pressure,UHP)、谷氨酰胺转胺酶处理(Transglutaminase,TG)及超高压协同TG酶处理(Ultra-high pressure synergistic Transglutaminase,UTG)的蛋清蛋白热诱导凝胶机理及结构的变化。结果表明:UHP-EWP、TG-EWP、UTG-EWP的硬度、弹性和持水性均有所提高,疏水相互作用力是维持凝胶的主要作用力;UHP-EWP、TG-EWP、UTG-EWP的α-螺旋含量均不同程度下降、β-折叠含量均上升;UHP-EWP的平均粒径值下降、电位绝对值下降,TG-EWP、UTG-EWP的变化与之相反;UHP-EWP、TG-EWP、UTG-EWP的游离巯基含量上升、总巯基含量下降、表面疏水性升高;凝胶结构更加致密光滑,平整度提高。本研究为蛋清蛋白热诱导凝胶改性提供了理论基础及研究思路。 展开更多
关键词 蛋清蛋白 超高压改性 TG 酶改性 凝胶特性
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活性炭制备的研究进展 被引量:1
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作者 潘晓威 梁耀辉 +4 位作者 占国艳 陈淑贤 潘政 何家媛 叶剑芝 《现代农业科技》 2024年第9期118-122,127,共6页
本文系统评述了近年来活性炭的主要制备方法,其中:化学活化法可短时间制备出高比表面积的活性炭,但会带来较严重的污染;与化学活化法相比,物理活化法具有工艺简单、清洁等优点,但所制备活性炭的孔结构较低,吸附性能偏弱;物理-化学活化... 本文系统评述了近年来活性炭的主要制备方法,其中:化学活化法可短时间制备出高比表面积的活性炭,但会带来较严重的污染;与化学活化法相比,物理活化法具有工艺简单、清洁等优点,但所制备活性炭的孔结构较低,吸附性能偏弱;物理-化学活化法结合物理活化法和化学活化法两种方法的优点,可调节活性炭结构,制备出合适的活性炭;微波加热活化法不仅可以降低预处理成本,还可以提高加热速率。本文还比较了不同改性方法的优劣,并对高比表面积活性炭的发展前景进行了展望。 展开更多
关键词 活性炭 制备方法 改性
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