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Compound 3k治疗骨关节炎:调控氧化应激通路改善软骨细胞糖酵解的作用机制 被引量:1
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作者 郭素蓉 曹士盛 +2 位作者 穆星彤 杨青 张娟 《中国组织工程研究》 CAS 北大核心 2025年第2期363-370,共8页
背景:骨关节炎现已被认为是一种代谢性疾病,既往研究表明糖酵解在骨关节炎的发生发展中起重要作用。Compound 3k作为一种新型糖酵解小分子抑制剂,具有抗炎及抗肿瘤等功效,因此可靶向糖酵解,有望为骨关节炎治疗提供新的思路。目的:基于... 背景:骨关节炎现已被认为是一种代谢性疾病,既往研究表明糖酵解在骨关节炎的发生发展中起重要作用。Compound 3k作为一种新型糖酵解小分子抑制剂,具有抗炎及抗肿瘤等功效,因此可靶向糖酵解,有望为骨关节炎治疗提供新的思路。目的:基于缺氧诱导因子1α/活性氧的氧化应激通路探究Compound 3k在糖酵解过度活跃所导致的骨关节炎中的作用机制。方法:取对数生长期的ATDC5成软骨细胞,用10 ng/mL白细胞介素1β作用24 h诱导骨关节炎体外细胞模型,以CCK-8法检测不同浓度(0.25,0.5,1,2.5,5,10,15μmol/L)Compound 3k的细胞毒性,选出合适浓度进行后续实验。将软骨细胞随机分为对照组、模型组、治疗组,模型组以10 ng/mL的白细胞介素1β诱导,治疗组以Compound 3k预刺激2 h后与白细胞介素1β共培养,用CCK-8法检测各组细胞增殖情况;用ELISA试剂盒检测各组细胞炎症水平;用试剂盒检测各组细胞活性氧、细胞外乳酸脱氢酶及葡萄糖含量;qRT-PCR及Western blot检测相关炎症因子白细胞介素6、肿瘤坏死因子α及糖酵解相关基因葡萄糖转运蛋白1、甘油醛3-磷酸脱氢酶、单羧酸转运蛋白1和缺氧诱导因子1α的表达水平。结果与结论:①与对照组相比,模型组细胞增殖活性下降、糖酵解水平活跃,表现为细胞外乳酸脱氢酶含量增加(P<0.001),葡萄糖含量减少(P<0.001),相关炎症因子白细胞介素6(P<0.0001)及肿瘤坏死因子α(P<0.001),糖酵解相关基因葡萄糖转运蛋白1(P<0.001)、甘油醛3-磷酸脱氢酶(P<0.001)、单羧酸转运蛋白1(P<0.001)及缺氧诱导因子1α(P<0.001)的表达水平均上调,并伴随氧化应激,活性氧过量产生。②与模型组相比,Compound 3k的治疗有效提高细胞增殖活性,抑制过度活跃的糖酵解水平的同时,抑制了骨关节炎软骨细胞炎症(P<0.001)及糖酵解相关基因的表达(P<0.001),且抑制氧化应激,缺氧诱导因子1α的表达水平下调(P<0.0001),活性氧水平下降。③上述结果证实,Compound 3k抑制了白细胞介素1β诱导的软骨细胞炎症,其机制可能与糖酵解及缺氧诱导因子1α/活性氧介导的氧化应激有关。 展开更多
关键词 骨关节炎 糖酵解 compound 3k 氧化应激 HIF-1α/ROS ATDC5细胞 葡萄糖代谢 白细胞介素1Β 小分子药物
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Secondary Compounds Assessment in Some Street Plants Exposed to Air Pollution in Jeddah Governorate, Kingdom of Saudi Arabia
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作者 Thorya A. Fallatah 《Open Journal of Ecology》 2025年第1期115-134,共20页
This research was carried out to identify the most effective plant species for air purification based on environmental factors. The existence of plants beside roadways can be considered a more efficient approach to im... This research was carried out to identify the most effective plant species for air purification based on environmental factors. The existence of plants beside roadways can be considered a more efficient approach to improving air quality and minimizing pollution exposure. The samples for this research were collected from various sites across the streets of Jeddah governorate. The primary sources of air pollution in the research area are vehicle traffic and emissions from cars. Eight species were gathered from various streets in Jeddah governorate, namely, Azadirachta indica, Senna sulfurea, Ziziphus spina-christi, Cordia sebestena, Tecoma stans, Bougainvillea spectabilis, Conocarpus lancifolius, and Ixora coccinea. The leaves of the studied plants were analyzed for secondary compounds using Gas chromatography-mass spectrometry (GC-MS) techniques. Gas-chromatographic analyses revealed that bis (2-ethylhexyl) phthalate was found in every plant. Bis-(2-ethylhexyl) phthalate, a widespread environmental pollutant. Moreover, Cordia sebestena was the sole plant that contained Phenol, 2,2’-methylenebis [6-(1,1-dimethylethyl)-4-methyl] which is part of the phenols category. Environmental conditions can affect the production of secondary metabolites. By tracking the concentrations of these substances, researchers can evaluate the well-being of ecosystems and identify pollution. 展开更多
关键词 Secondary compounds Street Plants Air Pollution Jeddah Governorate Gas Chromatography-Mass Spectrometry (GC-MS)
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Calculation of Compound Hazard Probability Using Convolution of Distributions
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作者 Luis Augusto Sanabria 《Atmospheric and Climate Sciences》 2025年第1期1-19,共19页
The hazard produced by natural phenomena on infrastructure and urban populations has been widely studied in the last 50 years. Researchers have recognised that the real danger posed by these phenomena depends on their... The hazard produced by natural phenomena on infrastructure and urban populations has been widely studied in the last 50 years. Researchers have recognised that the real danger posed by these phenomena depends on their extreme values. Most researchers focus on the extremes of natural phenomena considered in isolation, one variable at a time. However, what is relevant in hazard studies is coincident extremes of several climatic variables, i.e., the presence of compound extremes. The peak value of these extremes seldom coincides, but off-peak values located in the tail of the distributions are often concurrent and can lead to catastrophic events. What is essential in hazard studies is to calculate the probabilistic distribution of the extremes of coincident climatic variables. The presence of correlations between these variables complicates the problem. This paper presents a computationally efficient and robust mathematical methodology to solve the problem. The procedure is based on the convolution of the distributions of the climatic variables. Once the probabilistic distribution of the compound variables is found, it is possible to calculate the curves of the return period, which is the indicator of importance in hazard and risk studies. This compound Return Period is computed using the Statistics of Extreme Values. To illustrate the problem, the case of a cyclone landing close to a low-gradient coastal city is discussed, and its probability of flooding and recurrence period is calculated. We show that the failure to correctly model the correlation between variables can result in overestimating the Return Period curve, consequently increasing mitigation costs. 展开更多
关键词 Natural Hazards compound Extremes Mathematical Convolution
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Different administration regimens of compound tropicamide eyedrops for pupil dilation for children with dark iris:a randomized clinical trial
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作者 Xu Xu Lian-Xin Zhang Jing-Jing Jiang 《International Journal of Ophthalmology(English edition)》 2025年第3期415-419,共5页
AIM:To compare the efficacy of different administration regimens of compound tropicamide eyedrops(CTE)for pupil dilation for children with dark iris.METHODS:A prospective,comparative,randomized interventional study wa... AIM:To compare the efficacy of different administration regimens of compound tropicamide eyedrops(CTE)for pupil dilation for children with dark iris.METHODS:A prospective,comparative,randomized interventional study was conducted.Children in Group 1 received CTE 3 times with a 3min interval between each application.Children in Group 2 received CTE 4 times with a 5min interval between each application.We measured their pupil diameters at baseline(pre-drug instillation)and 30min and 60min post-drug instillation and assessed the pupillary light reflex at 60min post-drug instillation.RESULTS:In total,194 eyes of 101 children were enrolled.The changes of pupil diameter at 30min and 60min post-drug instillation were 1.2±0.6 mm and 2.3±1.0 mm in Group 1,and 2.3±0.9 mm and 3.7±1.0 mm in Group 2,respectively.Group 2 showed a larger change in pupil size than Group 1 at 30min(P<0.01)and 60min(P<0.01).The effect of pupil dilation in Group 2 was 1.25 times that in Group 1.The change in pupil size was positively associated with age.A higher proportion of children in Group 1 had smaller pupil diameter and reactive pupils at the final time point,with only 33 children(33.7%)had final pupil size≥6.5 mm,and only 9 children(9.2%)had non-reactive pupils.Children in Group 2 achieved larger pupil diameter and more nonreactive pupils at the final time point,with 84 children(87.5%)had final pupil size≥6.5 mm,and only 22 children(22.9%)had reactive pupils.CONCLUSION:Increasing the frequency of compound tropicamide and lengthening the interval between eye drop applications can produce stronger mydriatic effects. 展开更多
关键词 pupil dilation MYDRIASIS compound tropicamide dark iris CHILDREN
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Harnessing multi-omics approaches to elucidate the role of Chinese herbal compounds in chemotherapy-induced gastrointestinal damage
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作者 Chang Qiao Hao-Xiang Zhang +2 位作者 Xiao-Tong Tian Yan-Jing Zhang De-Hui Li 《World Journal of Gastrointestinal Oncology》 2025年第2期35-40,共6页
In this editorial,we discuss the findings reported by Wang et al in the latest issue of the World Journal of Gastrointestinal Oncology.Various research methodologies,including microbiome analysis,assert that the Tzu-C... In this editorial,we discuss the findings reported by Wang et al in the latest issue of the World Journal of Gastrointestinal Oncology.Various research methodologies,including microbiome analysis,assert that the Tzu-Chi Cancer-Antagonizing and Life-Protecting II Decoction of Chinese herbal compounds mitigates inflammatory responses by inhibiting the NF-κB signaling pathway.This action helps maintain the dynamic equilibrium of the intestinal microecology and lessens chemotherapy-induced gastrointestinal damage.The efficacy of these compounds is intimately linked to the composition of intestinal microbes.These compounds regulate intestinal microecology by virtue of their specific compatibility and effectiveness,thereby enhancing the overall therapeutic outcomes of cancer chemotherapy.Nonetheless,the exact mechanisms underlying these effects warrant further investigation.Multi-omics technologies offer a systematic approach to elucidate the mechanisms and effectiveness of Chinese herbal compounds in vivo.This manuscript reviews the application of multi-omics technologies to Chinese herbal compounds and explores their potential role in modulating the gastrointestinal microenvironment following cancer chemotherapy,thus providing a theoretical foundation for their continued use in adjunct cancer treatment. 展开更多
关键词 Chinese herbal compounds Gastrointestinal microenvironment CHEMOTHERAPY Multi-omics Intestinal microecology
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Intermetallic compounds for nitrogen electrochemistry
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作者 Haohong Wei Cheng Tang +6 位作者 Yanyun Wang Yongcheng Feng Huancong Shi Mingjin Cui Huakun Liu Shixue Dou Laiquan Li 《Green Energy & Environment》 2025年第2期268-291,共24页
Electrochemical nitrogen transformation techniques represent a burgeoning avenue for nitrogen pollutant remediation and synthesizing valuable nitrogenous products from atmospheric nitrogen.Intermetallic compounds(IMCs... Electrochemical nitrogen transformation techniques represent a burgeoning avenue for nitrogen pollutant remediation and synthesizing valuable nitrogenous products from atmospheric nitrogen.Intermetallic compounds(IMCs)nanocrystals,featured with unique geometric,electronic and functional properties,have emerged as promising candidates.The review discusses various synthesis approaches for IMCs,including thermal annealing,wet chemical synthesis,electrochemical synthesis,and other emerging methods,analyzing their advantages and limitations.Then we summarized the recent advances of IMCs in electrocatalytic nitrogen transformation reactions,such as nitrate reduction reaction,nitric oxide reduction reaction,nitrogen reduction reaction,and hydrazine oxidation reaction.Despite significant progress,challenges remain in the field,particularly in adopting more refined strategies to improve catalyst performance and stability.This review aims to comprehensively understand the structural properties of IMCs and their structure-performance relationship,guiding the development of more efficient and stable catalysts for future nitrogen electrochemistry. 展开更多
关键词 Intermetallic compounds ELECTROCATALYSIS Nitrogen transformation reactions Synthesis methods Catalyst design
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Compound Metalens Enabling Distortion-Free Imaging
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作者 Hanyu Zheng Fan Yang +5 位作者 Hung-I Lin Mikhail Y.Shalaginov Zhaoyi Li Padraic Burns Tian Gu Juejun Hu 《Engineering》 2025年第2期52-58,共7页
The emergence of metalenses has impacted a wide variety of applications such as beam steering,imaging,depth sensing,and display projection.Optical distortion,an important metric among many optical design specification... The emergence of metalenses has impacted a wide variety of applications such as beam steering,imaging,depth sensing,and display projection.Optical distortion,an important metric among many optical design specifications,has however rarely been discussed in the context of meta-optics.Here,we present a generic approach for on-demand distortion engineering using compound metalenses.We show that the extra degrees of freedom afforded by a doublet metasurface architecture allow custom-tailored angle-dependent image height relations and hence distortion control while minimizing other monochromatic aberrations.Using this platform,we experimentally demonstrate a compound fisheye metalens with diffraction-limited performance across a wide field of view of 140°and a low barrel distortion of less than 2%,compared with up to 22%distortion in a reference metalens without compensation.The design strategy and compound metalens architecture presented herein are expected to broadly impact metasurface applications in consumer electronics,automotive and robotic sensing,medical imaging,and machine vision systems. 展开更多
关键词 Metasurface Metalens Wide field of view Wavefront correction compound meta-optics
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Roles of the Tropical Intra-Seasonal Oscillations in the Sub-Seasonal Prediction of the Long-Lasting Compound Heatwave over Southern China in 2010
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作者 WANG Kai-qi ZHANG Tuan-tuan +5 位作者 YANG Song LIN Wen-shi WANG Wei-wei WANG Teng ZHANG Cheng-yang DONG Shao-rou 《Journal of Tropical Meteorology》 2025年第1期30-42,共13页
Sub-seasonal prediction of regional compound heatwaves and their predictability sources remain unclear.In this study,the underlying mechanisms for the long-lasting compound heatwave over Southern China during July 1–... Sub-seasonal prediction of regional compound heatwaves and their predictability sources remain unclear.In this study,the underlying mechanisms for the long-lasting compound heatwave over Southern China during July 1–18,2010,and the major sources of its sub-seasonal prediction skill are identified.The results show that both the development and decay of this compound heatwave are mainly dominated by atmospheric processes(i.e.,adiabatic heating associated with anticyclonic circulation),whereas land-atmosphere coupling processes play an important role in sustaining the heatwave.A further analysis indicates that by inducing anomalous anticyclonic circulations over Southern China,the tropical intraseasonal oscillations with periods of 30–60 days and 10–30 days facilitate the occurrence and maintenance of the heatwave during its entire and second half periods,respectively.The NCEP Climate Forecast System Version 2 shows a low skill in predicting the 2010 compound heatwave over Southern China when the lead time is longer than 2 pentads,which is largely attributed to the model’s bias in representing the intensity and phase of intra-seasonal oscillations. 展开更多
关键词 compound heatwave intra-seasonal oscillations sub-seasonal prediction Southern China
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Impacts of increasing compound hot-dry events on vegetation under the warming-wetting trend in Northwest China
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作者 Zejin Liu Limin Jiao Xihong Lian 《Geography and Sustainability》 2025年第2期32-43,共12页
In a warming world,climate extremes tend to be more frequent and intense.The exceptional response of ecosystems triggered by extreme climate events under a warmer and wetter climate in northwest China(NWC)has aroused ... In a warming world,climate extremes tend to be more frequent and intense.The exceptional response of ecosystems triggered by extreme climate events under a warmer and wetter climate in northwest China(NWC)has aroused growing concern.However,understanding the responses of vegetation to climate extremes from the compound events perspective remains challenging.In this study,we identify the climate dynamics in NWC during 1971–2020 based on daily meteorological observations,focusing on the changes in compound hot-dry events(CHDEs)during the warmer and wetter period.We further explore the effects of CHDEs on vegetation by examining vegetation anomalies and recovery time using daily gross primary productivity(GPP)data.The results show a clear warmer and wetter period in NWC during 2000–2020.No signs of a hiatus in CHDEs increase are observed during this period,and even the duration of CHDEs in western NWC keeps showing an increasing tendency.Vegetation in eastern NWC,with a lower probability of GPP anomalies,exhibits stronger resistance of ecosystems to CHDEs than in western NWC.In NWC,vegetation typically returns to its normal state in 5.50 days on average,but exhibits greater resilience in the western region,where it takes less recovery time(4.82 days).Vegetation in the central region shows the lowest probability of GPP anomalies and relatively longer recovery time,likely due to its higher altitudes.Our research underscores the imperative to address the considerable impacts of CHDEs on vegetation growth even as the regional climate becomes increasingly warmer and wetter. 展开更多
关键词 Warming-wetting trend compound hot-dry events Vegetation anomaly Recovery time
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A novel photocatalytic mechanism of volatile organic compounds degradation on BaTiO_(3) under visible light:Photo-electrons transfer from photocatalyst to pollutant
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作者 Teng Wang Jiachun Cao +2 位作者 Juan Li Didi Li Zhimin Ao 《Chinese Chemical Letters》 2025年第3期182-187,共6页
Wide bandgap semiconductors are typically activated under ultraviolet(UV)light irradiation for volatile organic compounds(VOCs)degradation.However,our previous study discovered that certain VOCs can interact with some... Wide bandgap semiconductors are typically activated under ultraviolet(UV)light irradiation for volatile organic compounds(VOCs)degradation.However,our previous study discovered that certain VOCs can interact with some wide bandgap semiconductors,formatting an intermediate bandgap between the VOCs and the conduction band of wide bandgap semiconductor,thus inducing visible light activation of the system,and photo-generated electrons are excited by visible light and transferred from the VOCs to the conduction band of semiconductor.In this work,BaTiO_(3),traditionally is not active under visible light irradiation,however showed degradation rates of 100%and 20%for styrene and toluene under visible light,respectively.Density functional theory(DFT)calculations indicate that the adsorption of styrene or toluene on the BaTiO_(3)surface reduces its bandgap from 2.93 eV to 1.36 eV and 2.26 eV,respectively.The intermediate bandgap in this system is primarily formed by the valence band of BaTiO_(3)and the VOCs,and indicating that photo-generated electrons directly transfer from BaTiO_(3)to the VOCs under visible light,inducing degradation reactions of VOCs,i.e.,this work discovered a new transfer pathway of photo-electrons direct from the valence band of BaTiO_(3)to VOCs,while photo-electrons are from VOCs to the conductive band of wide-bandgap semiconductors in our previous work. 展开更多
关键词 Volatile organic compounds Photocatalytic Degradation Wide-bandgap semiconductors Density functional theory Degradation mechanism
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The application and perspective of NMR and MS based strategies for functional compounds mining in medicinal and dietary plants
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作者 Bodou Zhang Sheng Li +6 位作者 Zhenzhen Liang Yinling Wei Jing Dong Hongyan Wen Lingli Guo Xiaojiang Hao Yu Zhang 《Food Science and Human Wellness》 2025年第1期50-63,共14页
Medicinal and dietary plants provide numerous nutritional and functional compounds and also have various potential health benefits to humanity.The specific and efficient techniques for accurate identification of nutri... Medicinal and dietary plants provide numerous nutritional and functional compounds and also have various potential health benefits to humanity.The specific and efficient techniques for accurate identification of nutritional compounds and functional metabolites is crucial for the development of functional foods from medicinal and dietary plants.Nuclear magnetic resonance(NMR)and mass spectrometry(MS)are indispensable and essential technologies that provide an unsurpassed wealth of untargeted identification,quantitative and qualitative analysis,and structural information in the study of food and plant products.In the past decade,the rapid development of modern analytical technology has led to the emergence of new approaches and strategies for natural products discovery.Especially the application of novel NMRand MS-based identification and dereplication strategies aided by artificial intelligence and machine learning algorithms have brought about a significant shift in the natural products discovery process.These developments and changes in the natural products filed have given us insights into how to accurately target and mining nutritional,functional,and bioactive compounds.Thus,we have summarized recent research on novel NMR and MS based strategies and methods focusing on functional compounds,accurate identification and efficient discovery mainly in medicinal and dietary plants.This review could provide a comprehensive perspective for a better understanding of novel strategies and methods based on NMR and MS technologies,which could provide valuable insights and ideas for functional compounds mining. 展开更多
关键词 Nuclear magnetic resonance(NMR) Mass spectrometry(MS) New strategies Functional compounds MINING
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Ultra-compact on-chip camera based on optoelectronic compound eyes with nonuniform ommatidia
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作者 Lin Zhu Yu-Qing Liu +4 位作者 Jia-Yi Wan Zhi-Juan Sun Dong-Dong Han Qi-Dai Chen Yong-Lai Zhang 《International Journal of Extreme Manufacturing》 2025年第1期543-553,共11页
Compound eyes(CEs)that feature ultra-compact structures and extraordinary versatility have revealed great potential for cutting-edge applications.However,the optoelectronic integration of CEs with available photodetec... Compound eyes(CEs)that feature ultra-compact structures and extraordinary versatility have revealed great potential for cutting-edge applications.However,the optoelectronic integration of CEs with available photodetectors is still challenging because the planar charge-coupled device(CCD)/complementary metal oxide semiconductor(CMOS)detector cannot match the spatially distributed images formed by CE ommatidia.To reach this end,we report here the optoelectronic integration of CEs by manufacturing 3D nonuniform ommatidia for developing an ultra-compact on-chip camera.As a proof-of-concept,we fabricated microscale CEs with uniform and nonuniform ommatidia through femtosecond laser two-photon photopolymerization,and compared their focusing/imaging performance both theoretically and experimentally.By engineering the surface profiles of the ommatidia at different positions of the CE,the images formed by all the ommatidia can be tuned on a plane.In this way,the nonuniform CE can be directly integrated with a commercial CMOS photodetector,forming an ultra-compact CE camera.Additionally,we further combine the CE camera with a microfluidic chip,which can further serve as an on-chip microscopic monitoring system.We anticipate that such an ultra-compact CE camera may find broad applications in microfluidics,robotics,and micro-optics. 展开更多
关键词 artificial compound eyes two-photon photopolymerization optical electronic integration
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Bimetallic composite carbon fiber with persulfate mediation for intercepting volatile organic compounds during solar interfacial evaporation
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作者 Yuling Ma Dongqing Liu +4 位作者 Tao Zhang Chengjie Song Dongmei Liu Peizhi Wang Wei Wang 《Chinese Chemical Letters》 2025年第3期151-155,共5页
Solar interfacial evaporation(SIE),is currently one of the most potential water supply technologies in the remote,insular,and disaster-stricken areas.However,the existence of volatile organic compounds(VOCs)in water d... Solar interfacial evaporation(SIE),is currently one of the most potential water supply technologies in the remote,insular,and disaster-stricken areas.However,the existence of volatile organic compounds(VOCs)in water deteriorates the distillate quality,threatening human health.Herein,we constructed a carbonbased bimetallic(C/FeCo)photothermal membrane by electrospinning technique.Results illustrated that the membrane can catalytically degrade VOCs during SIE with persulfate(PDS)mediation.PDS,as well as phenol,was mainly reacted on the interface of the photothermal membrane instead of in the bulk solution.The interception efficiency of phenol achieved nearly 100%using the C/FeCo membrane during SIE.Hydroxyl radical(•OH),sulfate radical(SO_(4)•−),superoxide radical(O_(2)•−),and singlet oxygen(^(1)O_(2))were identified as the main active substances to degrade VOCs.We also conducted SIE experiments using actual river water to evaluate the practical performance of the C/FeCo membrane.This work holds the promise of VOCs interception during SIE and enlarges the application of solar distillation in water/wastewater treatment. 展开更多
关键词 Solar distillation Interfacial evaporation Volatile organic compounds Bimetallic composite carbon fiber Persulfate mediation
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Determination of Perfluorinated Compounds in Milk Tea by High Performance Liquid Chromatography-Tandem Mass Spectrometry
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作者 Shu WANG Xianzhi JIANG +5 位作者 Juan LUO Qing LI Yaohong LIU Lijun LI Lei YI Dayunzi HUANG 《Agricultural Biotechnology》 2025年第1期64-68,共5页
[Objectives]This study was conducted to establish a detection method for the simultaneous determination of 18 perfluorinated compounds(PFCs)in milk tea by ultra-high performance liquid chromatography-tandem mass spect... [Objectives]This study was conducted to establish a detection method for the simultaneous determination of 18 perfluorinated compounds(PFCs)in milk tea by ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS).[Methods]The samples were first subjected to precipitation of proteins by potassium ferrocyanide solution and zinc acetate solution,and then extracted by acetonitrile and detected by LC-MS/MS.Next,sodium chloride was added,and after vortex centrifugation,the acetonitrile layer was dried by blowing with nitrogen.Subsequently,1 ml of methanol was added to prepare a test solution.An ACQUITY UPLC BEH C18(2.6 m,2.1 mm×100 mm)chromatographic column was used for liquid phase separation,and gradient elution was performed using 10 mmol ammonium acetate solution-acetonitrile as the mobile phase.The MS detection adopted the MRM mode for acquisition,positive and negative ion mode switching for simultaneous determination,and external standard method for quantification.[Results]In the linear ranges of the target substances,the correlation coefficients R^(2)were all greater than 0.99.The detection limits of the method was in the range of 0.001-0.05μg/kg,and the quantitation limits were in the range of 0.03-0.20 ng/L.The recovery values ranged from 72.8%to 110.5%.[Conclusions]This method has high sensitivity and good accuracy,and thus strong practical value. 展开更多
关键词 Liquid chromatography-tandem mass spectrometry Milk tea Perfluorinated compound
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Research and Exploration on Digitalization of Practical Teaching for Cultivating Compound Talents in Characteristic Pilot Software College
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作者 Yixian Liu Jun Guo +2 位作者 Xiaochun Yang Dongming Chen Zhiliang Zhu 《计算机教育》 2025年第3期55-61,共7页
In response to the current situation of practical teaching and the main problems in the teaching process of cultivating composite talents in the characteristic demonstration software college,this paper analyzes the im... In response to the current situation of practical teaching and the main problems in the teaching process of cultivating composite talents in the characteristic demonstration software college,this paper analyzes the importance of digital reform in practical teaching,introduces the work foundation,main work,reform characteristics,and effects of digital reform in practical teaching of composite talents in Software College of Northeastern University and lays the foundation for future in-depth research,providing reference for the digital reform of practical teaching in related majors of other colleges. 展开更多
关键词 compound talent cultivation Practical teaching digitalization Research and exploration
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Oxygen heterocyclic compounds(OHCs)in lemon oils are important markers in targeted HPLC analyses for authentication
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作者 Siyu Liu Shiming Li Chi-Tang Ho 《Food Science and Human Wellness》 2025年第2期421-428,共8页
Lemon oils are broadly used as flavoring agents in beverages,foods,cosmetics and pharmaceuticals,yet the adulteration of natural,particularly cold pressed lemon oils is very common in the industry due to its unmet dem... Lemon oils are broadly used as flavoring agents in beverages,foods,cosmetics and pharmaceuticals,yet the adulteration of natural,particularly cold pressed lemon oils is very common in the industry due to its unmet demand and high cost.Nowadays,most quality control(QC)analysis of lemon oils is conducted by gas chromatography(GC)analysis,which is far from a reliable method.Oxygen heterocyclic compounds(OHCs)in non-volatile fraction are gaining increasing attention in authentication process because of the nearly finger-printing profiles of OHCs in cold pressed citrus essential oils.Our goal in this study was to identify OHCs using high performance liquid chromatography(HPLC)in lemon oils,establish OHC profiles,perform stepwise logistic regression analysis(SLRA)and build effective predicting model and further determine adulterated lemon oils by referencing the OHC profiles and established models.After HPLC analyses,profiling and SLRA modeling of 154 OHCs samples of industrial lemon oils,we found that the combination of isopimpinellin and total OHC concentration are essential and robust predictors to differentiate authentic samples from adulterated lemon oils with a success rate of 98%from the 5-fold cross validation.This study provided a reliable and efficient method in determining the authenticity of lemon oils. 展开更多
关键词 Lemon oils Oxygen heterocyclic compounds High performance liquid chromatography(HPLC) AUTHENTICITY Targeted analysis Quality control
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Compound hot drought events in the Mei-yu region:influences from polar and tropical regions
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作者 Huixin Li Bo Sun +4 位作者 Zhongshi Zhang Huijun Wang Yeran Zhou Jiani Zeng Botao Zhou 《Science Bulletin》 2025年第2期273-282,共10页
In the Mei-yu region,there has been noticeable increase in the occurrence of compound hot drought(CHD)events in recent years.However,the underlying causes of these occurrences remain poorly understood.To address this ... In the Mei-yu region,there has been noticeable increase in the occurrence of compound hot drought(CHD)events in recent years.However,the underlying causes of these occurrences remain poorly understood.To address this knowledge gap,we conducted a comprehensive study utilizing observational datasets,reanalysis datasets,and four numerical experiments to investigate the associated physical mechanisms.Our findings indicated that the prevalence of CHD events in the Mei-yu region is influenced strongly by two key factors:the decline in Barents Sea ice during February and the presence of a La Ni?alike pattern of sea surface temperature(SST)in April.The decline in Barents Sea ice generates an anomalous Rossby wave in the Arctic that propagates southeastward.The La Ni?a-like SST pattern regulates a Rossby wave over western America,propagating along the subtropical jet stream.These two Rossby waves induce northward movement and strengthened intensity of the subtropical westerly jet in East Asia.The local circulation patterns in the Mei-yu region are influenced by the position and intensity of the subtropical jet,leading to downward motion in accordance with the secondary circulation theory for high-altitude jet streams.Consequently,these local circulation patterns might contribute to occurrence of CHD events.Moreover,our analysis revealed that the impact of Barents Sea ice and the La Nina-like SST pattern can explain approximately two-thirds of the mild CHD events in the Mei-yu region,and that the influence of each is relatively independent.This research underscores influences of polartropical systems on climate extremes in eastern Asia. 展开更多
关键词 compound hot drought events Mei-yu region June-July Barents Sea ice La Niña-like SST Respective and combined influences
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Upgrading of 6–0 mm low rank high sulfur lignite by a compound dry cascade separation bed
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作者 Xiaodong Yu Deqing Gan 《International Journal of Mining Science and Technology》 2025年第2期307-324,共18页
In this paper,the effect of vibration intensity on the spatial distribution of sulfur content in bed particles was studied.The effects of vibration and airflow on the mechanical characteristics of particles were studi... In this paper,the effect of vibration intensity on the spatial distribution of sulfur content in bed particles was studied.The effects of vibration and airflow on the mechanical characteristics of particles were studied,the collision behavior mode of particles was determined,the spatial saltation law of particles was investigated,the spatial functional axis of beds was determined,and the saltation separation period of particles was determined.The test results show that:When separation bed provides inlet airflow velocity(U_(in)) is 2.55 m/s,the airflow distribution interval of I,II and III areas were U_(I)=2.55-2.57 m/s,U_(II)=1.33-1.35 m/s,U_(III)=0.35-0.38 m/s,respectively;when separation bed vibration amplitude (A)A=2.4-2.5 mm,separation bed vibration frequency (f) f=23-24 Hz,the desulfurization effect is the best.When vibration intensity (Γ)Γ=1.22,U_(in)=1.05 m/s,the particles have disordered contact and collision behavior.WhenΓ=14.89,U_(in)=3.18 m/s,the particles have a transition cataclastic collision.WhenΓ=5.80,U_(in)=2.55 m/s,the particles have directional collision behavior.It is determined that the OX axis is the transverse stable diffusion axis of the material,the OY axis is the longitudinal gradient transport axis of the material,and the OZ axis is the vertical density cascade distribution axis of the material.When separation time (T) T=0-10 s was the period of disorderly diffusion and mixing of particles,T=10-20 s was the period of directional migration and stratification of particles,and T=20-30 s was the period of cascade distribution and separation of particles.Finally,separation experiments conducted under optimal operating parameters demonstrated that the clean coal yield was 72.02%with a sulfur content of 0.98%. 展开更多
关键词 Low rank high sulphur lignite compound dry cascade separation bed Desulfurization and ash reduction Particle space transition
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A Biomimetic Stress Field Modulation Strategy Inspired by Scorpion Compound Slit Sensilla Enabled High-Accuracy and Low-Power Positioning Sensor for Identifying the Load Incident Angles
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作者 Junqiu Zhang Yu Chen +11 位作者 Haoran Li Jiqi Gao Xiangbo Gu Jiachao Wu Xiaojing Qin Kejun Wang Bin Zhu Daobing Chen Tao Sun Jianhua Fan Zhiwu Han Luquan Ren 《Journal of Bionic Engineering》 2025年第2期727-738,共12页
Numerous arthropods evolve and optimize sensory systems, enabling them to effectively adapt complex and competitive habitats. Typically, scorpions can precisely perceive the prey location with the lowest metabolic rat... Numerous arthropods evolve and optimize sensory systems, enabling them to effectively adapt complex and competitive habitats. Typically, scorpions can precisely perceive the prey location with the lowest metabolic rate among invertebrates. This biological phenomenon contrasts sharply with engineered systems, which generally associates high accuracy with substantial energy consumption. Inspired by the Scorpion Compound Slit Sensilla (SCSS) with a stress field modulation strategy, a bionic positioning sensor with superior precision and minimal power consumption is developed for the first time, which utilizes the particular Minimum Positioning Units (MPUs) to efficiently locate vibration signals. The single MPU of the SCSS can recognize the direction of collinear loads by regulating the stress field distribution and further, the coupling action of three MPUs can realize all-angle vibration monitoring in plane. Experiments demonstrate that the bionic positioning sensor achieves 1.43 degrees of angle-error-free accuracy without additional energy supply. As a proof of concept, two bionic positioning sensors and machine learning algorithm are integrated to provide centimeter (cm)-accuracy target localization, ideally suited for the man-machine interaction. The novel design offers a new mechanism for the design of traditional positioning devices, improving precision and efficiency in both the meta-universe and real-world Internet-connected systems. 展开更多
关键词 Scorpion compound Slit Sensilla(SCSS) Vibration Source Stress Field Modulation Strategy High-accuracy and low-power Positioning Sensor Minimum Positioning Unit(MPU)
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Comparative evaluation of commercial Douchi by different molds:biogenic amines,non-volatile and volatile compounds 被引量:3
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作者 Aijun Li Gang Yang +4 位作者 Zhirong Wang Shenglan Liao Muying Du Jun Song Jianquan Kan 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期434-443,共10页
To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fer... To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fermentation of Douchi.The results showed that the biogenic amine contents of the three types of Douchi were all within the safe range and far lower than those of traditional fermented Douchi.Aspergillus-type Douchi produced more free amino acids than the other two types of Douchi,and its umami taste was more prominent in sensory evaluation(P<0.01),while Mucor-type and Rhizopus-type Douchi produced more esters and pyrazines,making the aroma,sauce,and Douchi flavor more abundant.According to the Pearson and PLS analyses results,sweetness was significantly negatively correlated with phenylalanine,cysteine,and acetic acid(P<0.05),bitterness was significantly negatively correlated with malic acid(P<0.05),the sour taste was significantly positively correlated with citric acid and most free amino acids(P<0.05),while astringency was significantly negatively correlated with glucose(P<0.001).Thirteen volatile compounds such as furfuryl alcohol,phenethyl alcohol,and benzaldehyde caused the flavor difference of three types of Douchi.This study provides theoretical basis for the selection of starting strains for commercial Douchi production. 展开更多
关键词 DOUCHI Starting strains Non-volatile compounds Volatile compounds Sensory evaluation
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