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NIR-Ⅱfluorescence lateral flow immunosensor based on efficient energy transfer probe for point-of-care testing of tumor biomarkers 被引量:1
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作者 Zhaorui Song Qiulian Hao +5 位作者 Bing Li Yuwei Yuan Shanshan Zhang Yongkuan Suo Hai-Hao Han Zhen Cheng 《Chinese Chemical Letters》 2025年第1期469-473,共5页
Fluorescence lateral flow immunoassay(LFA)has emerged as a powerful tool for rapid screening of various biomarkers owing to its simplicity,sensitivity and flexibility.It is noteworthy that fluorescent probe mainly det... Fluorescence lateral flow immunoassay(LFA)has emerged as a powerful tool for rapid screening of various biomarkers owing to its simplicity,sensitivity and flexibility.It is noteworthy that fluorescent probe mainly determines the analytical performance of LFA.Due to the emission and excitation wavelengths are located in the visible region,most fluorophores are inevitably subject to light scattering and background autofluorescence.Herein,we reported a novel LFA sensor based on the second near-infrared(NIR-Ⅱ)fluorescent probe with excellent anti-interference capability.The designed NIR-Ⅱprobe was the Nd^(3+)and Yb^(3+)doped rare earth nanoparticles(RENPs)by employing Nd^(3+)as energy donor and Yb^(3+)as energy acceptor,which of the donor-acceptor energy transfer(ET)efficiency reached up to 80.7%.Meanwhile,relying on the convenient and effective encapsulation strategy of poly(lactic-co-glycolic acid)(PLGA)microspheres to RENPs,the surface functionalized NIR-Ⅱprobe(RE@PLGA)was obtained for subsequent bioconjugation.Benefiting from the optical advantages of NIR-Ⅱprobe,this proposed NIR-ⅡLFA displayed a good linear relationship ranging from 7 ng/mL to 200 ng/mL for the detection ofα-fetoprotein(AFP),an important biomarker of hepatocellular carcinoma(HCC).The limit of detection(LOD)was determined as low as 3.0 ng/m L,which was of 8.3 times lower than clinical cutoff value.It is promising that LFA sensor based on this efficient RENPs probe provides new opportunities for high sensitive detection of various biomarkers in biological samples. 展开更多
关键词 Donor-acceptor energy transfer(ET) Lateral flow immunoassay(LFA) The second near-infrared(NIR-Ⅱ) FLUORESCENCE Rare-earth nanoparticles(RENPs) Poly(lactic acid-co-glycolic acid)(PLGA) Tumor biomarker
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Mechanical properties of surface soil in alpine meadow and its relationship with soil cracking in Qinghai Province,China
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作者 ZHANG Hailong ZHU Haili +5 位作者 WU Yuechen XU Pengkai HONG Chenze LIU Yabin LI Guorong HU Xiasong 《Journal of Arid Land》 2025年第5期644-663,共20页
Surface soil cracking in alpine meadows signifies the transition of degradation from quantitative accumulation to qualitative deterioration.Quantitative research remains insufficient regarding changes in the mechanica... Surface soil cracking in alpine meadows signifies the transition of degradation from quantitative accumulation to qualitative deterioration.Quantitative research remains insufficient regarding changes in the mechanical properties of degraded meadow soils and the mechanical thresholds for cracking initiation.This study explored the relationships between surface cracking and the physical properties,tensile strength,and matrix suction of root-soil composites in alpine meadow sites with different stages of degradation(undegraded(UD),lightly degraded(LD),moderately degraded(MD),and heavily degraded(HD))under different water gradients(high water content(HWC),medium water content(MWC),and low water content(LWC))corresponding to different drying durations at a constant temperature of 40.0°C.The Huangcheng Mongolian Township in Menyuan Hui Autonomous County,Qinghai Province,China was chosen as the study area.The results indicated that as the degradation degree of alpine meadow intensified,both water content of rootsoil composite and the fine grain content of soil decreased.In contrast,the root-soil mass ratio and root area ratio initially increased and then decreased with progressive degradation.Under a consistent water content,the tensile strength of root-soil composite followed a pattern of MD>HD>LD>UD.The peak displacement of tensile strength also decreased as the degradation degree of alpine meadow increased.Both the tensile strength and matrix suction of root-soil composite increased as root-soil water content decreased.A root-soil water content of 30.00%-40.00%was found to be the critical threshold for soil cracking in alpine meadows.Within this range,the matrix suction of root-soil composite ranged from 50.00 to 100.00 kPa,resulting in the formation of linear cracks in the surface soil.As the root-soil water content continued to decrease,liner cracks evolved into branch-like and polygonal patterns.The findings of this study provide essential data for improving the mechanical understanding of grassland cracking and its development process. 展开更多
关键词 DEGRADATION alpine meadow root-soil composite tensile strength matrix suction grassland crack
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Temperature-pressure coupled experiments and response mechanisms of permeability evolution in deep continental shale
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作者 KANG Zhiqin WANG Jiawei +7 位作者 WANG Lei LI Wei YANG Dong ZHAO Jing YU Lingjie ZHAO Yangsheng YANG Xiaoming REN Siqi 《Petroleum Exploration and Development》 2025年第6期1515-1526,共12页
To address the unclear permeability evolution mechanisms during in-situ conversion of deep continental shale,this study employs a pioneering online THMC(thermo-hydro-mechanical-chemical)-CT coupled experimental system... To address the unclear permeability evolution mechanisms during in-situ conversion of deep continental shale,this study employs a pioneering online THMC(thermo-hydro-mechanical-chemical)-CT coupled experimental system to investigate the permeability evolution,dynamic pore-fracture structural responses,and hydrocarbon production behavior under high-temperature and high-stress conditions.The results show that:(1)Under high stress constraints(axial/confining stresses of 50/25,100/50 MPa),shale permeability exhibits a three-stage evolution with increasing temperature,including a low-permeability stage(25-350℃),a rapid-increase stage(350-450℃),and a significant-decrease stage(450-600℃).(2)Under coupled in-situ stress(25/20 MPa axial/confining stress)and temperature,fractures undergo a dynamic“two-expansion and two-contraction”process,where the first expansion(25-300℃)and first contraction(300-350℃)correspond to the low-permeability stage,the second expansion(350-450℃)corresponds to the rapid-increase stage,and the second contraction(450-550℃)corresponds to the significant-decrease stage.(3)The controlling mechanisms at each stage are as follows:at temperatures up to 350℃,the maximum yield of retained oil and the filling of heavy hydrocarbons in pores and fractures result in reduced permeability.Between 350℃ and 450℃,thermal cracking and kerogen decomposition jointly enhance pore-fracture network development.Above 450℃,illitization of clay minerals,matrix plastic deformation,and fracture closure under stress result in permeability reduction.These findings clarify the staged permeability behavior and associated mechanisms,providing essential theoretical and experimental support for the temperature-stress synergistic optimization of in-situ shale oil conversion processes. 展开更多
关键词 Ordos Basin Triassic Yanchang Formation deep continental shale shale oil in-situ modification high temperature and high pressure PERMEABILITY real-time CT scanning response mechanism
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Deformable hyaluronic acid niosomes overcome multi-barriers for improved ergothioneine transdermal delivery against UV-induced skin damage
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作者 Lijun Li Chenliang Guo +8 位作者 Yuelin Fang Zijian Cheng Yaowei Li Zhangyu Wang Dian Cai Yuqi Xu Wenqi Liu Shouwei Ma Xinxin Zhang 《Chinese Chemical Letters》 2025年第11期369-376,共8页
The complex skin structure and insufficient intracellular entrapment limit the therapeutic effects of active substances,therefore appealing to a more effective transdermal drug delivery system design.Herein,a hyaluron... The complex skin structure and insufficient intracellular entrapment limit the therapeutic effects of active substances,therefore appealing to a more effective transdermal drug delivery system design.Herein,a hyaluronic acid(HA)modified steareth-2-based niosomes(HA-nio)with satisfactory deformability and targeting properties was designed for ergothioneine(EGT)(EGT@HA-nio)against ultraviolet(UV)-induced skin damage.The unique composition allows EGT@HA-nio to exhibit high mechanical softness,making it deformable to pass through the stratum corneum by the intercellular space without rupture.For further intracellular delivery,HA modification enables EGT to target human dermal cells(HDFs)with increased distribution in mitochondria without the restriction of specific EGT transporter-organic cation transporter1(OCTN-1).Benefiting from the above properties,an adequate amount of EGT in the active form was accumulated in the desired cellular sites,alleviating UV-radiation-induced reactive oxygen species(ROS)generation,inflammatory factor release,DNA damage,and mitochondrial dysfunction.The in vivo experimental results show that EGT@HA-nio could significantly decrease collagen degradation,restore epidermal thickness and morphology to healthy levels,and effectively prevent UV-induced skin damage.With the ability to penetrate biological barriers and deliver drugs,HA-nio may promote the development of inadequate drug penetration disease treatment including skin diseases,cancers,and bacterial infections. 展开更多
关键词 Transdermal delivery ERGOTHIONEINE DEFORMABILITY NIOSOMES UV-induced skin damage
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Understanding of endo/lysosomal escape of nanomaterials in biomedical application
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作者 Xin Wang Haoyu Li +1 位作者 Chen Chen Zhihui Liang 《Smart Molecules》 2025年第4期33-46,共14页
Emerging therapies rely on the efficient and specific delivery of targeted agents into the cytosol,such as DNA,siRNA and proteins.Nanoparticles showed great potentials in safe delivery and transportation of the target... Emerging therapies rely on the efficient and specific delivery of targeted agents into the cytosol,such as DNA,siRNA and proteins.Nanoparticles showed great potentials in safe delivery and transportation of the targeted cargoes;however,the entrapment in endosomes and degradation by specific enzymes in the lysosome hindered the bioavailability,cytosolic delivery and subsequent therapeutic efficacy.In this case,the development of methods for efficient and specific delivery of targeted therapeutic agents focuses on overcoming the major challenge of endo/lysosomal escape,which relies on the development of safe and efficient nanodelivery systems.A deeper mechanistic understanding in the endo/lysosomal escape will guide the development of more efficient nano-delivery systems.In this review,we summarize various mechanisms by which nanoparticles escape from the endo/lysosome,and showcase the recent progress in dissecting the endo/lysosomal approaches based on nano-delivery systems.Emphasis will lie on the properties of nanoparticles that govern the endo/lysosomal escape pathway as well as the latest promising applications in vaccine delivery and genetic engineering field. 展开更多
关键词 biomedical application endo/lysosomal escape nanomaterials property
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Computation assisted chemical study of photo-induced late-stage skeleton transformation of marine natural products towards new scaffolds with biological functions
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作者 Quan Xu Ye-Qing Du +8 位作者 Pan-Pan Chen Yili Sun Ze-Nan Yang Hui Zhang Bencan Tang Hong Wang Jia Li Yue-Wei Guo Xu-Wen Li 《Chinese Chemical Letters》 2025年第5期364-368,共5页
A computer-assisted chemical investigation of an intriguing photoreaction of norditerpenoids(3-7)has been first reported,leading to not only their biomimetic conversion,but also the generation of several new products ... A computer-assisted chemical investigation of an intriguing photoreaction of norditerpenoids(3-7)has been first reported,leading to not only their biomimetic conversion,but also the generation of several new products with uncommon 4,14-dioxabicyclo[10.2.1]pentadecane scaffold(8,9,12-14).In bioassay,compounds 10 and 15 exhibited significant stimulation of GLP-1 secretion.This study has given an insight for the application of computational methods on the late-stage skeleton transformation of complex natural products towards new bioactive compounds. 展开更多
关键词 Marine natural product PHOTOSYNTHESIS DFT calculation Biomimetic conversion GLP-1
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提拉法生长锗酸铋晶体的结晶习性 被引量:2
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作者 廖晶莹 R.C.deBoor P.Bennema 《人工晶体学报》 EI CAS CSCD 1992年第4期329-336,共8页
介绍了提拉法生长锗酸铋单晶(Bi_4 Ge_3 O_(12),简称 BGO)在不同生长条件下的结晶形貌。根据 Gibss-Wulf 晶体生长最小表面能原理,利用 Hartman 对晶体外部结构分析的 PBC 理论和Bennema 等人提出的形态重要性理论,得到的 BGO 晶体 F ... 介绍了提拉法生长锗酸铋单晶(Bi_4 Ge_3 O_(12),简称 BGO)在不同生长条件下的结晶形貌。根据 Gibss-Wulf 晶体生长最小表面能原理,利用 Hartman 对晶体外部结构分析的 PBC 理论和Bennema 等人提出的形态重要性理论,得到的 BGO 晶体 F 晶面的形态重要性顺序,在已知晶体生长取向的情况下,我们就能够推测 BGO 晶体在扩大面上出现的棱和柱体上可能出现的晶面。这种推测晶体形貌的模型与实验结果很好一致。 展开更多
关键词 锗酸铋晶体 结晶 熔盐法
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KDP晶体缺陷形成机理的研究 被引量:6
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作者 王耀水 朱锐 +11 位作者 叶桂芬 刘向阳 洪远珍 蔡诗武 Bennema P. VanEnckvort W.J.P. VanKessel J.W.M. Dam B 《无机材料学报》 SCIE EI CAS CSCD 北大核心 1989年第2期108-111,共4页
采用激光散射层析术及 X 射线形貌术研究了 KDP(KH_2PO_4)晶体中散射颗粒及位错等缺陷的形成机理。作者采用微分干涉衬差显微镜(DICM)装置、通过录相放大系统观察研究了晶体生长过程中有机和无机固态包杂物的成因。
关键词 KDP晶体 磷酸二氢钾 位错
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Risk assessment and binding mechanisms of potentially toxic metals in sediments from different water levels in a coastal wetland 被引量:2
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作者 Fusheng Sun Guanghui Yu +3 位作者 Xingxing Han Zhilai Chi Yunchao Lang Congqiang Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第7期202-212,共11页
The excessive accumulation of potentially toxic metals(Pb and Cd)in coastal wetlands is among the main factors threateningwetland ecosystems.However,the effects ofwater table depth(WTD)on the risk and binding mechanis... The excessive accumulation of potentially toxic metals(Pb and Cd)in coastal wetlands is among the main factors threateningwetland ecosystems.However,the effects ofwater table depth(WTD)on the risk and binding mechanisms of potentially toxic metals in sediments remain unclear.Here,sediments from different WTD obtained from a typical coastal wetland were evaluated using a newly developed strategy based on chemical extraction methods coupled with high-resolution spectroscopy.Our findings indicated that the WTD of the coastal wetland fluctuates frequently and the average enrichment factor for Pb was categorized as minor,whereas Cd enrichment was categorized as moderate.High-resolution spectroscopy techniques also demonstrated that organic functional groups and partly inorganic compounds(e.g.,Fe-O/Si-O)played a vital role in the binding of Pb and Cd to surface sediments.Additionally,mineral components rather than organic groups were mainly bound to thesemetals in the bottom sediments.Collectively,our findings provide key insights into the potential health effects and binding characteristics of potentially toxic metals in sediments,as well as their dynamic behavior under varying sediment depths at a microscale. 展开更多
关键词 Coastal wetlands Wetland sediment Toxic metals Risk assessment Synchrotron radiation Binding mechanisms
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Risk assessment of fault reactivation considering the heterogeneity of friction strength in the BZ34-2 Oilfield,Huanghekou Sag,Bohai Bay Basin,China 被引量:5
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作者 Ye-Jun Jin Ling-Dong Meng +4 位作者 Ding-You Lyu Xiao-Fei Fu Jiang-Bo Huang Si-Jia Cao Jian-Da Li 《Petroleum Science》 SCIE EI CSCD 2023年第5期2695-2708,共14页
The hazards of fault reactivation caused by fluid injection are a growing concern.However,traditional evaluation methods of fault stability are likely to underestimate the risk in fault segments with a high clay conte... The hazards of fault reactivation caused by fluid injection are a growing concern.However,traditional evaluation methods of fault stability are likely to underestimate the risk in fault segments with a high clay content.Therefore,an extended evaluation method of fault stability(ECPP)incorporating the heterogeneity in friction strength caused by variation in the clay content within the fault zone is established in this study.After characterizing the current stress field of the BZ34-2 Oilfield in the Huanghekou Sag,Bohai Bay Basin,the reactivation potential of faults is evaluated using both traditional and ECPP methods.Traditional evaluation of fault stability shows that all faults are stable in the present stress field.Faults oriented ENE have a relatively high risk.The maximum sustainable fluid pressure Δp is approximately 8.8-8.9 MPa and 9.3-9.9 MPa.When considering the heterogeneity in fault friction strength,the fault stability is clearly controlled by the clay content of the faults.The high-risk fault segments assessed using traditional methods are no longer obvious,which reflects the importance of incorporating friction strength heterogeneity in the process of fault evaluation.Moreover,the results also show that most fault segments are activated when the fault zone is dominated by montmorillonite,reflecting the strong influence of clay mineral types on fault stability.The factors influencing the heterogeneity of fault friction strength are very complicated in actual situations.Therefore,future work should focus on establishing a database through a large number of experiments and investigating the relationship between the friction coefficient and the main controlling factors. 展开更多
关键词 Faultreactivation In-situ stress Strength heterogeneity of fault friction Huanghekou Sag
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Engineering a High-Selectivity PVDF Hollow-Fiber Membrane for Cesium Removal 被引量:6
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作者 Shiyuan Ding Lilan Zhang +1 位作者 Yang Li Li’an Hou 《Engineering》 SCIE EI 2019年第5期865-871,共7页
In this study,a copper ferrocyanide/silica/polyvinylidene fluoride(CuFC/SiO2/PVDF)hollow-fiber composite membrane was successfully synthesized through a facile and effective crosslinking strategy.The PVDF hollow-fiber... In this study,a copper ferrocyanide/silica/polyvinylidene fluoride(CuFC/SiO2/PVDF)hollow-fiber composite membrane was successfully synthesized through a facile and effective crosslinking strategy.The PVDF hollow-fiber membrane with embedded SiO2 was used to fix the dispersion of CuFC nanoparticles for cesium(Cs)removal.The surface morphology and chemical composition of the composite membrane were analyzed using scanning electron microscopy and X-ray photoelectron spectroscopy(XPS).The composite membrane showed a high Cs rejection rate and membrane flux at the three layers of CuFC and 0.5%SiO2,and its Cs rejection rate was not affected by variation in the pH(pH=4–10).The modified membrane could be effectively regenerated many times using ammonium nitrate(NH4NO3).The Cs selectivity performance was verified by an efficient Cs rejection rate(76.25%and 88.67%in 8 h)in a solution of 100 lg L 1 of Cs with 1 mmol L 1 of competing cations(K+and Na+).The CuFC/SiO2/PVDF hollowfiber composite membrane showed a particularly superior removal performance(greater than 90%)in natural surface water and simulated water with a low Cs concentration.Therefore,the CuFC/SiO2/PVDF hollow-fiber composite membrane can be used directly in engineering applications for the remediation of radioactive Cs-contaminated water. 展开更多
关键词 CESIUM REMOVAL Composite membrane Copper FERROCYANIDE Polyvinylidene FLUORIDE
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RIM工艺中的注射压力效应 被引量:2
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作者 徐强 刘远中 张宏娟 《聚氨酯工业》 1997年第3期8-10,共3页
探讨了注射压力变化引起的RIM工艺中的各种效应。提出了确定注射压力应考虑的事项。
关键词 聚氨酯 注塑成型 压力效应 成型
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Characterization of alpine meadow surface crack and its correlation with root-soil properties 被引量:1
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作者 WU Yuechen ZHU Haili +5 位作者 ZHANG Yu ZHANG Hailong LIU Guosong LIU Yabin LI Guorong HU Xiasong 《Journal of Arid Land》 SCIE CSCD 2024年第6期834-851,共18页
Quantifying surface cracks in alpine meadows is a prerequisite and a key aspect in the study of grassland crack development.Crack characterization indices are crucial for the quantitative characterization of complex c... Quantifying surface cracks in alpine meadows is a prerequisite and a key aspect in the study of grassland crack development.Crack characterization indices are crucial for the quantitative characterization of complex cracks,serving as vital factors in assessing the degree of cracking and the development morphology.So far,research on evaluating the degree of grassland degradation through crack characterization indices is rare,especially the quantitative analysis of the development of surface cracks in alpine meadows is relatively scarce.Therefore,based on the phenomenon of surface cracking during the degradation of alpine meadows in some regions of the Qinghai-Tibet Plateau,we selected the alpine meadow in the Huangcheng Mongolian Township,Menyuan Hui Autonomous County,Qinghai Province,China as the study area,used unmanned aerial vehicle(UAV)sensing technology to acquire low-altitude images of alpine meadow surface cracks at different degrees of degradation(light,medium,and heavy degradation),and analyzed the representative metrics characterizing the degree of crack development by interpreting the crack length,length density,branch angle,and burrow(rat hole)distribution density and combining them with in situ crack width and depth measurements.Finally,the correlations between the crack characterization indices and the soil and root parameters of sample plots at different degrees of degradation in the study area were analyzed using the grey relation analysis.The results revealed that with the increase of degradation,the physical and chemical properties of soil and the mechanical properties of root-soil composite changed significantly,the vegetation coverage reduced,and the root system aggregated in the surface layer of alpine meadow.As the degree of degradation increased,the fracture morphology developed from"linear"to"dendritic",and eventually to a complex and irregular"polygonal"pattern.The crack length,width,depth,and length density were identified as the crack characterization indices via analysis of variance.The results of grey relation analysis also revealed that the crack length,width,depth,and length density were all highly correlated with root length density,and as the degradation of alpine meadows intensified,the underground biomass increased dramatically,forming a dense layer of grass felt,which has a significant impact on the formation and expansion of cracks. 展开更多
关键词 alpine meadow grassland degradation grassland cracks crack characterization index crack morphology root length density grey relation analysis
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Prediction of second-order rate constants between carbonate radical and organics by deep neural network combined with molecular fingerprints 被引量:5
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作者 Peizhe Sun Huixin Ma +2 位作者 Shangyu Li Hong Yao Ruochun Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第1期438-441,共4页
Carbonate radical is among the most important environmental relevant reactive species which govern the transformation and fate of pharmaceutical contaminants(PCs).However,reaction rate constants between carbonate radi... Carbonate radical is among the most important environmental relevant reactive species which govern the transformation and fate of pharmaceutical contaminants(PCs).However,reaction rate constants between carbonate radical and most of the PCs have not been experimentally determined,and quantitative structural-activity relationships(QSARs)have not been established for rate estimation.This study applied Max Min data processing method and used molecular fingerprints(MF)as the input of a deep neural network(DNN)to predict the rate constants between carbonate radical and organic compounds.MF parameters and the hyper-structure of the DNN were adjusted to yield satisfactory accuracy of rate prediction.The vector length of 512 bits with radius of 1 for MF and 5 hidden layers gave the best performance.The optimized MaxMin-MF-DNN model was compared with some of the most commonly used QSARs and machine learning methods,including random data splitting,molecular descriptors,supporting vector machine,decision tree,etc.Results showed that the MF-DNN model out-performed the other methods by more than 10%increase in prediction accuracy.Applying this MF-DNN model,we estimated reaction rates between carbonate radical and pharmaceuticals used in human medicine(1576)and veterinary practice(390).Among them,46 drugs were identified as fast-reacting compounds,suggesting the important relations of their environmental fate with carbonate radical. 展开更多
关键词 Deep neural network Carbonate radical Molecular fingerprints QSAR Pharmaceuticals
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Five new terpenoids from Viburnum odoratissimum var.sessiliflorum 被引量:2
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作者 LI Yang JIAN Yajiao +7 位作者 XU Fan LUO Yongxin LI Zhixuan OU Yi WEN Yan JIN Jingwei ZHANG Chuarui GAN Lishe 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2023年第4期298-307,共10页
Five new terpenoids,including two vibsane-type diterpenoids(1,2)and three iridoid allosides(3-5),together with eight known ones,were isolated from the leaves and twigs of Viburnum odoratissimum var.sessiliflorum.Their... Five new terpenoids,including two vibsane-type diterpenoids(1,2)and three iridoid allosides(3-5),together with eight known ones,were isolated from the leaves and twigs of Viburnum odoratissimum var.sessiliflorum.Their planar structures and relative configurations were determined by spectroscopic methods,especially 2D NMR techniques.The sugar moieties of the iridoids were confirmed asβ-D-allose by GC analysis after acid hydrolysis and acetylation.The absolute configurations of neovibsanin Q(1)and dehydrovibsanol B(2)were determined by quantum chemical calculation of their theoretical electronic circular dichroism(ECD)spectra and Rh2(OCOCF_(3))_(4)-induced ECD analysis.The anti-inflammatory activities of compounds 1,3,4,and 5 were evaluated using an LPS-induced RA W264.7 cell model.Compounds 3 suppressed the release of NO in a dose-dependent manner,with an IC_(50) value of 55.64μmol·L^(-1).The cytotoxicities of compounds 1-5 on HCT-116 cells were assessed and the results showed that compounds 2 and 3 exhibited moderate inhibitory activities with IC_(50) values of 13.8 and 12.3μmol·L^(-1),respectively. 展开更多
关键词 Viburnum odoratissimum var.sessilifolrum TERPENOIDS Acid hydrolysis ECD calculation ANTI-INFLAMMATION
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云母增强聚氨酯RIM材料研究 被引量:1
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作者 董火成 《化学推进剂与高分子材料》 CAS 2003年第3期1-2,共2页
通过试验 ,探索了云母材料的粒度、用量对聚氨酯RIM材料性能及工艺的影响 ,找出了其用量对聚氨酯RIM弹性体性能的影响规律 ,为开发云母增强聚氨酯RIM制品打下了基础。
关键词 云母增强 聚氨酯 RIM弹性体 研究 性能 工艺
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Varying water column stability controls the denitrification process in a subtropical reservoir,Southwest China 被引量:1
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作者 Gaoyang Cui Xiao-Dong Li +5 位作者 Siqi Li Shiyuan Ding Qinkai Li Mengdi Yang Hong Lv Yiyao Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第1期208-219,共12页
Reservoirs are regarded as hotspots of nitrogen transformation and potential sources of nitrous oxide(N_(2)O).However,it remains unclear how the hydrological conditions due to dam construction control the processes of... Reservoirs are regarded as hotspots of nitrogen transformation and potential sources of nitrous oxide(N_(2)O).However,it remains unclear how the hydrological conditions due to dam construction control the processes of nitrogen transformation in reservoir waters.To address this issue,we examined the spatial-temporal characteristics of nitrate concentrations,δ^(15)N-NO_(3)^(-),δ^(18)O-NO_(3)^(-),δ^(18)O-H_(2)O,relative water column stability(RWCS),and related environmental factors in a subtropical eutrophic reservoir(Hongfeng Reservoir,HFR),Southwest China.We found that denitrification was the most important nitrogen transformation process in the HFR and that higher denitrification intensity was associated with increased RWCS in summer,which suggested hydrological control of the denitrification process.In contrast,low RWCS conditions favored the nitrification process in the HFR in winter.Additionally,dissolved oxygen(DO;p<0.05)and nitrate concentrations(p<0.01)had significant impacts on the denitrification rate.We also found that the spatiotemporal RWCS variations were a prerequisite for regulating DO/nitrate stratification and the coupling/decoupling of nitrification-denitrification at the local and global scales.This study would advances our knowledge of the impacts of RWCS and thermal stratification on nitrogen transformation processes in reservoirs. 展开更多
关键词 Thermal stratification RWCS DENITRIFICATION Nitrogen transformation RESERVOIR
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如何打造新一代移动员工
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作者 刘征宇 《IT经理世界》 2009年第8期33-33,共1页
在市场竞争的不断变化和升级的环境下,现代企业既要拥有先进的理念和产品,还要持续提升运营和决策效率,才能敏锐地发现并把握更多的商机,实现稳健的增长。近年来,企业员工通过移动终端获取企业经营信息,参与运营决策的工作方式越... 在市场竞争的不断变化和升级的环境下,现代企业既要拥有先进的理念和产品,还要持续提升运营和决策效率,才能敏锐地发现并把握更多的商机,实现稳健的增长。近年来,企业员工通过移动终端获取企业经营信息,参与运营决策的工作方式越发流行,由此塑造了新的群体——Comidor Warrior。 展开更多
关键词 企业员工 现代企业 决策效率 市场竞争 经营信息 移动终端 运营 商机
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企业如何实施移动战略
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作者 刘征宇 《IT经理世界》 2009年第7期41-41,共1页
要在当今的市场上取得成功,仅仅保持公司本部的高效运作远远不够。成功的企业深刻认识到,必须让知识员工能够从多个地点完成工作。实施移动战略(不仅仅包括移动电子邮件访问)能够帮助企业提高生产率、降低成本并提升经营收入。
关键词 企业 知识员工 电子邮件 经营收入 生产率 市场 公司 地点
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