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Automatic extraction and structuration of soil–environment relationship information from soil survey reports 被引量:9
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作者 WANG De-sheng LIU Jun-zhi +3 位作者 ZHU A-xing WANG Shu ZENG Can-ying MA Tianwu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第2期328-339,共12页
In addition to soil samples, conventional soil maps, and experienced soil surveyors, text about soils(e.g., soil survey reports) is an important potential data source for extracting soil–environment relationships. Co... In addition to soil samples, conventional soil maps, and experienced soil surveyors, text about soils(e.g., soil survey reports) is an important potential data source for extracting soil–environment relationships. Considering that the words describing soil–environment relationships are often mixed with unrelated words, the first step is to extract the needed words and organize them in a structured way. This paper applies natural language processing(NLP) techniques to automatically extract and structure information from soil survey reports regarding soil–environment relationships. The method includes two steps:(1) construction of a knowledge frame and(2) information extraction using either a rule-based method or a statistic-based method for different types of information. For uniformly written text information, the rule-based approach was used to extract information. These types of variables include slope, elevation, accumulated temperature, annual mean temperature, annual precipitation, and frost-free period. For information contained in text written in diverse styles, the statistic-based method was adopted. These types of variables include landform and parent material. The soil species of China soil survey reports were selected as the experimental dataset. Precision(P), recall(R), and F1-measure(F1) were used to evaluate the performances of the method. For the rule-based method, the P values were 1, the R values were above 92%, and the F1 values were above 96% for all the involved variables. For the method based on the conditional random fields(CRFs), the P, R and F1 values for the parent material were, respectively, 84.15, 83.13, and 83.64%; the values for landform were 88.33, 76.81, and 82.17%, respectively. To explore the impact of text types on the performance of the CRFs-based method, CRFs models were trained and validated separately by the descriptive texts of soil types and typical profiles. For parent material, the maximum F1 value for the descriptive text of soil types was 90.7%, while the maximum F1 value for the descriptive text of soil profiles was only 75%. For landform, the maximum F1 value for the descriptive text of soil types was 85.33%, which was similar to that of the descriptive text of soil profiles(i.e., 85.71%). These results suggest that NLP techniques are effective for the extraction and structuration of soil–environment relationship information from a text data source. 展开更多
关键词 soil–environment relationship TEXT natural LANGUAGE processing extraction structuration
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Accounting Regulation Research and Structuration Theory
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作者 Anthony Moung Yin Chan 《Journal of Modern Accounting and Auditing》 2015年第3期131-137,共7页
This paper considers accounting regulation research from a structuration and cultural perspective. Therefore, accounting regulation research spans over three spheres of enquiry: (1) an accounting focus of standard-... This paper considers accounting regulation research from a structuration and cultural perspective. Therefore, accounting regulation research spans over three spheres of enquiry: (1) an accounting focus of standard-setting; (2) a cultural analysis in an empirical context; and (3) the use of a research methodology drawn from Anthony Giddens' structuration theory. In such approach, accounting regulation research analyzes the accounting regulation actors drawing upon the cultures in their standard-setting actions and interactions, referring to Giddens' three structural properties of meaning, power, and morality. The integration of these three spheres of enquiry is not entirely original. A few prior studies have similar combinations: Although they stress the uses and consequences of accounting systems in producing and reproducing organizational culture and negotiating meaning at the organizational level, this paper chooses the research approach of contextual analysis of accounting systems at more macro-societal and cultural levels. This different research interest and design provides this paper with its distinguishable characteristic from the prior similar studies. 展开更多
关键词 accounting standard-setting accounting and culture structuration analysis accounting regulation
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Application of Structuration Theory and Activity Theory in Enterprise Resources Planning Systems Implementation for Universities
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作者 Clement Mayieko Nyandiere Faustin Kamuzora Ismail Ateya Lukandu 《Computer Technology and Application》 2012年第5期383-392,共10页
An integration of organization culture in the conceptualization and development of Enterprise Resource Planning Systems (ERPs) is critical for an organization to reap potential benefits of the system. In this paper,... An integration of organization culture in the conceptualization and development of Enterprise Resource Planning Systems (ERPs) is critical for an organization to reap potential benefits of the system. In this paper, the authors present an analytical approach through the Structuration Theory: How a university can assess its culture for the purposes of design and development of the ERPs. The authors extend the Structuration Theory by integrating it with the Activity Theory to provide the means of evaluating the activities that the system is to perform. The modified Orlikowski model is applied to depict the relationship between institutional properties, human agents, and technology in the university setup and how this offers a more inclusive approach to ERP systems development and implementation. 展开更多
关键词 structuration theory activity theory information systems ERPs (enterprise resource planning systems) organization culture.
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Cyclic Pulsating Pressure Enhanced Segregating Structuration of Ultra-High Molecular Weight Polyethylene/Graphene Composites as High-performance Light-Weight EMI Shields 被引量:2
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作者 Yun-Zhi Huang Xiao-Xiao Liu +3 位作者 Lan-Wei Li Guang-Ming Huang Zhao-Xia Huang Jin-Ping Qu 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第7期958-967,I0008,共11页
Currently,the enhancement in electromagnetic interference(EMI)performance of polymeric composite generally relies on either improving electrical conductivity(σ)for stronger electromagnetic(EM)reflections or tailoring... Currently,the enhancement in electromagnetic interference(EMI)performance of polymeric composite generally relies on either improving electrical conductivity(σ)for stronger electromagnetic(EM)reflections or tailoring structure for higher EM resonances.Herein,we proposed a novel technique called cyclic pulsating pressure enhanced segregating structuration(CPP-SS),which can reinforce these two factors simultaneously.The structural information was supplied by optical microscopy(OM)and scanning electron microscopy(SEM),both of which confirmed the formation and evolution of segregate structured ultra-high molecular weight polyethylene(UHMWPE)/graphene composites.Then,the result showed that CPP-SS can significantly improve theσof samples.Ultimately,advanced specific EMI shielding efficiency of 31.1 d B/mm was achieved for UHMWPE/graphene composite at 1-mm thickness and a low graphene loading of 5 wt%.Meanwhile,it also confirmed that the intrinsic disadvantage of poor mechanical properties of conventional segregated structure composites can be surpassed.This work is believed to provide a fundamental understanding of the structural and performance evolutions of segregated structured composites prepared under CPPSS,and to bring us a simple and efficient approach for fabricating high-performance,strong and light-weight polymeric EMI shields. 展开更多
关键词 Cyclic pulsating pressure Segregated structure Ultra-high molecular weight polyethylene GRAPHENE Electromagnetic interface
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Diversity and Genetic Structuration of Populations of <i>Plutella xylostella</i>(Lepidoptera, Plutellidae), Cabbage Farming Destroyer in Senegal
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作者 Toffène Diome Mamecor Faye +2 位作者 Marième Seck Cheikh Tidiane Niass Mbacké Sembène 《Advances in Entomology》 2022年第1期1-13,共13页
<div style="text-align:justify;"> <i>Plutella xylostella</i>, pointed out as the most dangerous destroyer of cabbage<span "=""> (<i></i><i><i>Br... <div style="text-align:justify;"> <i>Plutella xylostella</i>, pointed out as the most dangerous destroyer of cabbage<span "=""> (<i></i><i><i>Brassica olerarea</i></i></span>), is a cosmopolitan species. In fact, owing to its large capacity of adaptation, <i></i><i><i>P. xylestella</i></i> colonizes any kind of area. This insect can bring about up to 90% of losses on cabbage farming. To control the insect, Senegalese farmers, very often, resort to high dose of chemical pesticides which are repetitively sprayed. The use of these chemical products gives rise to different varieties of resistant insects, which results in the emergence of different haplotypes between populations. It is in such a context that this study has been undertaken. Our objective is then to contribute to the knowledge of the genetic diversity of <i></i><i><i>P. xylostella</i></i> populations in Senegal. To hit the target, PCR- Sequencing method has been applied on samples from the five following localities: Diofior, Malika, Mboro, Santh Ndong, and Sebikotane. <i></i><i><i>P. xylostella</i></i> from Mboro is genetically different from the other populations. This fact could be due to a different way of using pesticides in this area vis-à-vis of the other localities. On the other hand, between populations of <i></i><i><i>P. xylostella</i></i> from Diofior, Malika, Santh Ndong, and Sebikotane, there is no significant genetic difference. In other respects, phylogenetic trees reveal the existence of two clades: one with individuals from Mboro and the other one with individuals from the other four localities. <i></i><i><i>P. xylostella</i></i> from Mboro distinguishes itself from other populations and then, can be regarded as a sub-population. Thus, the phylogenetic trees reveal the existence of two groups of <i></i><i><i>P. xylostella</i></i> in Senegal. </div> 展开更多
关键词 Brassica oleracea Genetic Diversity Genetic Structure
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New Expansion Dynamics Applied to the Planar Structures of Satellite Galaxies and Space Structuration
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作者 Jacques Fleuret 《Journal of Modern Physics》 2016年第16期2357-2365,共10页
Recent observations of Dwarf Satellite Galaxies (DSG) show that they have a clear tendency to stay in particular planes. Explanations with standard physics remain controversial. Recently, I proposed a new explanation ... Recent observations of Dwarf Satellite Galaxies (DSG) show that they have a clear tendency to stay in particular planes. Explanations with standard physics remain controversial. Recently, I proposed a new explanation of the galactic flat rotation curves, introducing a new cosmic acceleration due to expansion. In this paper, I apply this new acceleration to the dynamics of DSG’s (without dark matter). I show that this new acceleration implies planar structures for the DSG trajectories. More generally, it is shown that this acceleration produces a space structuration around any massive center. It remains a candidate to explain several cosmic observations without dark matter. 展开更多
关键词 Dwarf Satellite Galaxies Dark Matter Expansion Flat Rotation Curves GALAXIES Structure GRAVITATION SYMMETRY
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Hydrothermal conversion from hydrogarnet to hydroandradite based on alumina recovery from red mud 被引量:1
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作者 Hong-fei WU Xiao-lin PAN +3 位作者 Ji-long LIU Feng QIU Tun HE Hai-yan YU 《Transactions of Nonferrous Metals Society of China》 2026年第1期309-322,共14页
To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM ... To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM methods,and a novel hydrothermal process based on the conversion principle was finally proposed.The crystal structure simulation shows that the HA with varied silicon saturation coefficients is more stable than HG,and the HA with a high iron substitution coefficient is more difficult to be converted from HG.The(110)plane of Fe_(2)O_(3) is easier to combine with HG to form HA,and the binding energy is 81.93 kJ/mol.The effects of raw material ratio,solution concentration and hydrothermal parameters on the conversion from HG to HA were revealed,and the optimal conditions for the alumina recovery were obtained.The recovery efficiencies of alumina and Na_(2)O from the RM are 63.06%and 97.34%,respectively,and the Na_(2)O content in the treated RM is only 0.13%. 展开更多
关键词 HYDROGARNET hydroandradite structural stability hydrothermal conversion red mud
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Inverse design framework of hybrid honeycomb structure with high impact resistance based on active learning 被引量:1
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作者 Xingyu Shen Ke Yan +5 位作者 Difeng Zhu Hao Wu Shijun Luo Shaobo Qi Mengqi Yuan Xinming Qian 《Defence Technology(防务技术)》 2026年第1期407-421,共15页
In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honey... In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honeycomb cells,was created by constructing arrangement matrices to achieve structural lightweight.The machine learning(ML)framework consisted of a neural network(NN)forward regression model for predicting impact resistance and a multi-objective optimization algorithm for generating high-performance designs.The surrogate of the local design space was initially realized by establishing the NN in the small sample dataset,and the active learning strategy was used to continuously extended the local optimal design until the model converged in the global space.The results indicated that the active learning strategy significantly improved the inference capability of the NN model in unknown design domains.By guiding the iteration direction of the optimization algorithm,lightweight designs with high impact resistance were identified.The energy absorption capacity of the optimal design reached 94.98%of the EARE honeycomb,while the initial peak stress and mass decreased by 28.85%and 19.91%,respectively.Furthermore,Shapley Additive Explanations(SHAP)for global explanation of the NN indicated a strong correlation between the arrangement mode of HCS and its impact resistance.By reducing the stiffness of the cells at the top boundary of the structure,the initial impact damage sustained by the structure can be significantly improved.Overall,this study proposed a general lightweight design method for array structures under impact loads,which is beneficial for the widespread application of honeycomb-based protective structures. 展开更多
关键词 Re-entrant honeycomb Hybrid structures Inverse design Impact resistance LIGHTWEIGHT
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Post-translational control of biotic stress-related nicotine biosynthesis by a MAP kinase signaling cascade 被引量:1
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作者 Yan Zhou Yongliang Liu +5 位作者 Ruiqing Lyu Sanjay Kumar Singh Xueyi Sui Xin Hou Sitakanta Pattanaik Ling Yuan 《The Crop Journal》 2026年第1期201-213,共13页
The evolutionarily conserved mitogen-activated protein kinase(MAPK)cascades relay extracellular signals into cells,triggering a variety of cellular responses.We previously revealed NtMPK4 as a positive regulator of ni... The evolutionarily conserved mitogen-activated protein kinase(MAPK)cascades relay extracellular signals into cells,triggering a variety of cellular responses.We previously revealed NtMPK4 as a positive regulator of nicotine biosynthesis;however,its upstream regulation remains unclear.Here,we characterized a MAPK cascade,comprising NtMEKK1b,NtMPKK2a,and NtMPK4,that promotes nicotine biosynthesis.This signaling module transduces external cues,including jasmonate and pathogen elicitors such as flg22,into post-translational modifications that enhance transcriptional activity and pathway gene expression.NtMPKK2a physically interacts with and phosphorylates NtMPK4 in vivo,confirming its role as an upstream kinase.RNAi-mediated silencing of NtMPKK2a significantly reduced the expression of nicotine pathway genes and decreased nicotine accumulation,whereas induced-overexpression of NtMPKK2a upregulated nicotine pathway genes and increased nicotine contents in tobacco hairy roots.Overexpression of NtMPKK2a in tobacco cells enhanced the transactivation activity of a NIC2-locus Ethylene Response Factor NtERF221 on Putrescine N-methyltransferase(NtPMT)promotor,further supporting its role in promoting nicotine biosynthesis.Furthermore,we identified NtMEKK1b,a tobacco MEKK that interacts with NtMAPKK2a in yeast cells.Knock-down of NtMEKK1b in transgenic tobacco plants attenuated the expression of nicotine pathway genes and reduced nicotine contents,whereas induced-overexpression of NtMEKK1b upregulated gene expression and nicotine accumulation.Our findings uncover a previously uncharacterized MAPK cascade module,NtMEKK1b-NtMPKK2a-NtMPK4,that regulates nicotine biosynthesis,highlighting the importance of posttranslational regulation in nicotine biosynthesis. 展开更多
关键词 Nicotine biosynthesis Specialized metabolites MAPK cascade Post-translational regulation Alkaloid biosynthesis Structural modeling
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Commissioning of a radiofrequency quadrupole cooler‑buncher for collinear laser spectroscopy 被引量:1
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作者 Yin‑Shen Liu Han‑Rui Hu +15 位作者 Xiao‑Fei Yang Wen‑Cong Mei Yang‑Fan Guo Zhou Yan Shao‑Jie Chen Shi‑Wei Bai Shu‑Jing Wang Yong‑Chao Liu Peng Zhang Dong‑Yang Chen Yan‑Lin Ye Qi‑Te Li Jie Yang Stephan Malbrunot‑Ettenauer Simon Lechner Carina Kanitz 《Nuclear Science and Techniques》 2026年第1期193-201,共9页
A RadioFrequency Quadrupole(RFQ)cooler-buncher system was developed and implemented in a collinear laser spectroscopy setup.This system converts a continuous ion beam into short bunches while enhancing the beam qualit... A RadioFrequency Quadrupole(RFQ)cooler-buncher system was developed and implemented in a collinear laser spectroscopy setup.This system converts a continuous ion beam into short bunches while enhancing the beam quality and reducing the energy spread.The functionality of the RFQ cooler buncher was verified through offline tests with stable rubidium and indium beams delivered from a surface ion source and a laser ablation ion source,respectively.Bunched ion beams with a full width at half maximum of approximately 2μs in the time-of-flight spectrum were successfully achieved with a transmission efficiency exceeding 60%.The implementation of the RFQ cooler-buncher system also significantly improved the overall transmission efficiency of the collinear laser spectroscopy setup. 展开更多
关键词 Radiofrequency quadrupole cooler-buncher Collinear laser spectroscopy Hyperfine structure Time of flight
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Discovery of A New Sesquiterpene-Lactone from Streptomyces aureus SP-371
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作者 Zhang Tao Ji Zhenyu +1 位作者 Tang Gongli Hou Xianfeng 《有机化学》 北大核心 2026年第2期689-692,共4页
new sesquiterpene-lactone,designated as neopentalenolactone D1(1),was isolated from the fermentation cultures of Streptomyces aureus SP-371,which is known for producing agricultural-bactericide aureonuclemycin.The che... new sesquiterpene-lactone,designated as neopentalenolactone D1(1),was isolated from the fermentation cultures of Streptomyces aureus SP-371,which is known for producing agricultural-bactericide aureonuclemycin.The chemical structure of compound 1 was determined to be a neopentapyrrole natural product with a 5/5/6 tricyclic skeleton and one amide functional group,by using spectroscopic techniques such as nuclear magnetic resonance(1D/2D NMR)and high-resolution mass spectrometry(HR-ESI-MS).Its structural information indicates that it is probably the shunt product of neopentalenolactone biosynthetic pathway.In antibacterial activity evaluations,compound 1 demonstrated no inhibitory effects against the tested strains including Escherichia coli(DH5a),Staphylococcus aureus,and Bacillus subtilis under the experimental conditions. 展开更多
关键词 Streptomyces aureus sesquiterpene-lactone structural elucidation biosynthetic pathway
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Mechanism of microstructural evolution in coke during the co-pyrolysis of coking coal with organic additives
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作者 ZHAO Xinni TIAN Lu +3 位作者 YU Peng XU Xiuli DOU Jinxiao YU Jianglong 《燃料化学学报(中英文)》 北大核心 2026年第2期153-165,共13页
To deepen understanding of the evolution of coal char microstructural properties of coal char during the co-pyrolysis of coking coal with additives,this study incorporated two typical additives,coal tar pitch(CTP)and ... To deepen understanding of the evolution of coal char microstructural properties of coal char during the co-pyrolysis of coking coal with additives,this study incorporated two typical additives,coal tar pitch(CTP)and waste plastic(HDPE),into a blended coal sample and carried out pyrolysis experiments.The pyrolysis process and the microstructure of char were systematically characterized using various analytical techniques,including thermogravimetric analysis(TGA),X-ray diffraction(XRD)and Raman spectroscopy.Data correlation analysis was performed to reveal the mechanism of carbon structural ordering evolution within the critical temperature range(350−600℃)from colloidal layer formation to semi-coke conversion in coking coal,and to elucidate the regulatory effects of different additives on coal pyrolysis pathways.The results indicate that HDPE releases free radicals during high-temperature pyrolysis,accelerating the pyrolysis reaction and increase the yield of volatile components.Conversely,CTP facilitates pyrolysis at low temperatures through its light components,thereby delaying high-temperature reactions due to the colloidal layer’s effect.XRD results indicate that during the process of pyrolysis,there is a progressive decrease in the interlayer spacing of aromatic layers(d002),while the aromatic ring stacking height(L_(c))and lateral size(L_(a))undergo significant of carbon skeleton ordering.Further comparative reveals that CTP partially suppresses structural ordering at low temperatures,whereas HDPE promotes the condensation and alignment of aromatic clusters via a free radical mechanism.Raman spectroscopy reveals a two-stage reorganization mechanism in the microstructure of the coal char:the decrease in the I_(D)/I_(G)ratio between 350 and 550℃is primarily attributed to the cleavage of aliphatic side chains and cross-linking bonds,leading to a reduction in defective structures;whereas the increase in ID/IG between 550 and 600℃is closely associated with enhanced condensation reactions of aromatic structures.Correlation analysis further demonstrates progressive graphitization during pyrolysis,with a significant positive correlation(R^(2)>0.85)observed between d002 and the full width at half maximum of the G-band(FWHM-G). 展开更多
关键词 coking coal organic additives CO-PYROLYSIS colloidal layer carbon structure
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Metal-free brush-like 3D carbon nitride delivers efficient red-light-driven photocatalysis
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作者 WANG Peng HAN Yanling +2 位作者 LIU Yuanyuan LU Pengfei LI Xiao 《燃料化学学报(中英文)》 北大核心 2026年第3期92-104,共13页
In this study,melamine and cyanuric acid were used as precursors to form supramolecular crystals via hydrogen-bond-assisted self-assembly followed by hydrothermal treatment.Subsequent high-temperature calcination yiel... In this study,melamine and cyanuric acid were used as precursors to form supramolecular crystals via hydrogen-bond-assisted self-assembly followed by hydrothermal treatment.Subsequent high-temperature calcination yielded a novel brush-like three-dimensional carbon nitride.The brush-like 3D architecture was found to expose more accessible active sites,markedly accelerate electron transfer,and suppress the recombination of photogenerated charge carriers.The resulting superoxide(O_(2)^(-·))and hydroxyl(·OH)radicals generated via electron reduction were identified as the key reactive species in the photocatalytic process.Moreover,the surface of the brush-like structure is enriched with nitrogen vacancies,which enhance the catalyst’s ability to harvest visible light.The photocatalytic performance of the brush-like CNS-650 catalyst was evaluated for rhodamine B(RhB)degradation.Under red-light irradiation(660 nm),its degradation rate was 7.4 times higher than that of bulk CN.This work provides valuable insights into the design and application of efficient metal-free 3D photocatalysts. 展开更多
关键词 PHOTOCATALYSIS carbon nitride three dimensional structure RED-LIGHT
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Discovery of a Novel Ginseng Polysaccharide:Structure Characterization,in vitro Fermentability and Anti-oxidative Mechanism of Fermented Product via the Nrf2/HO-1 Pathway on Aβ-induced-PC 12 Cells
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作者 DONG Binbin HOU Zong +3 位作者 ZHENG Zhong XING Junpeng LIU Zhiqiang LIU Shu 《高等学校化学学报》 北大核心 2026年第1期173-189,共17页
In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented... In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs. 展开更多
关键词 Ginseng polysaccharide Structural characterization Intestinal microbiota FERMENTABILITY Oxidative stress
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Characterization of Glutarimide Derivatives from Agrimonia pilosa-Associated Endophytic Streptomyces sp.YINM00048
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作者 Su Yuying Wang Yingfang +4 位作者 Yi Mengzhuo Zhao Lixing Li Jiaxuan Ma Ling Yin Min 《有机化学》 北大核心 2026年第1期289-294,共6页
Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 k... Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 known compounds were isolated from the liquid fermentation broth of endophytic Streptomyces sp.YINM00048 obtained from Agrimonia pilosa.Their structures were elucidated through comprehensive spectroscopic analysis,including nuclear magnetic resonance,high-resolution mass spectrometry,and single-crystal X-ray diffraction,supported by time-dependent density functional theory(TDDFT)-electronic circular dichroism(ECD)calculations.Furthermore,compound 2 displayed weak cytotoxic activity against A549 and SMMC-7721 cell lines with IC50 values of 62.69 and 55.07μmol/L,respectively. 展开更多
关键词 Agrimonia pilosa endophytic Streptomyces glutarimide structural elucidation anti-tumor activity
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Co(Ⅱ) and Ni(Ⅱ) complexes of 3,3-diphenylpropionic acid and 2,2′-dipyridylamine: Structures and biological activities
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作者 FENG Jing WANG Renshu +1 位作者 WANG Hu LIU Hailong 《无机化学学报》 北大核心 2026年第3期617-631,共15页
Two Co(Ⅱ)and Ni(Ⅱ)complexes were synthesized by synergistic coordination of 3,3-diphenylpropionic acid(HDPA)and 2,2′-bipyridylamine(PAm).The structures of complexes[Co(DPA)_(2)(PAm)]·2H_(2)O(1)and[Ni(DPA)_(2)(... Two Co(Ⅱ)and Ni(Ⅱ)complexes were synthesized by synergistic coordination of 3,3-diphenylpropionic acid(HDPA)and 2,2′-bipyridylamine(PAm).The structures of complexes[Co(DPA)_(2)(PAm)]·2H_(2)O(1)and[Ni(DPA)_(2)(PAm)]·2H_(2)O(2)were determined by single-crystal X-ray diffraction,IR spectroscopy,and powder X-ray diffraction.Hirshfeld surface analysis provided quantitative insights into the intermolecular interactions within the complexes,while molecular docking studies elucidated their binding modes and affinities toward urease.Furthermore,the biological activities of both complexes were systematically evaluated through a range of assays,including DNA binding,urease inhibition,antibacterial activity,and in vitro cytotoxicity against cancer cells.Both complexes exhibited binding affinity for DNA and displayed notable urease inhibitory activity.Under in vitro conditions,both complexes showed appreciable cytotoxicity toward HepG2 cells with efficacy comparable to clinically used platinumbased anticancer agents.CCDC:2479943,1;2479944,2. 展开更多
关键词 crystal structure computational analysis urease inhibition antibacterial activity CYTOTOXICITY
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Structural Influence on Radiation-induced Single-event Effects in SiC MOSFETs:Comparative Analysis of Planar and Trench Designs
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作者 HU Libin FENG Shaohui +7 位作者 SUI Chenglong WANG Chengjie CHEN Miao LU Peng YANG Can SHU Lei LU Jiang LI Bo 《原子能科学技术》 北大核心 2026年第3期745-751,共7页
The single-event susceptibility of three silicon carbide(SiC)metal-oxide-semiconductor field-effect transistor(MOSFET)power devices structures(planar,trench and double trench)is researched by the technology computer-a... The single-event susceptibility of three silicon carbide(SiC)metal-oxide-semiconductor field-effect transistor(MOSFET)power devices structures(planar,trench and double trench)is researched by the technology computer-aided design(TCAD)simulation.Comparative analysis of the heavy-ion irradiation effects on three device structures reveals distinct susceptibility characteristics.The gate oxide region is identified as the most sensitive position in planar devices,while trench and doubletrench structures exhibit no localized sensitive regions.Furthermore,the single-event susceptibility demonstrates strong depth dependence across all three structures,with enhanced vulnerability observed at greater ion penetration depths. 展开更多
关键词 SiC MOSFET single-event susceptibility different structures TCAD simulation
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Crystal structure,thermal analysis,and luminescence properties of six heterocyclic lanthanide complexes
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作者 SONG Zihe ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2026年第1期181-192,共12页
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'... Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6. 展开更多
关键词 lanthanide complexes fluorescence property crystal structure thermal analysis
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