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Pd-catalyzed B—H bond activation and annulation of nido-carborane with terminal olefins: Facile construction of 2D-3D fused polycyclic compounds
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作者 SUN Fangxiang ZHANG Qing +6 位作者 ZHANG Yifan SUN Haoyi Akim VShmal′ko Sergey AAnufriev Igor BSivaev TU Deshuang YAN Hong 《无机化学学报》 北大核心 2026年第3期467-478,共12页
To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nido... To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nidocarboranes and alkynes directly afford two distinct types of 2D-3D fused carboranyl polycyclic compounds:3a-3f,4a-4d.The structures of this series of compounds were characterized by nuclear magnetic resonance spectroscopy,single-crystal X-ray diffraction,and high-resolution mass spectrometry,and a plausible reaction mechanism was proposed.Crystal structures reveal that the multiple rings in such 2D-3D fused carboranyl polycyclic compounds exhibit a certain degree of coplanarity.Furthermore,these compounds exhibited properties distinct from those of conventional 2D polycyclic systems.CCDC:2481988,3c,2481990,3f,2481986,4d. 展开更多
关键词 CARBORANE B—H bond activation polycyclic compounds
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Pressure-induced high-energy-density and superhard Be-C-O compounds
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作者 Jinming Zhu Kuo Bao +3 位作者 Zhaoqing Wang Yuan Qin Hongyu Yu Tian Cui 《Matter and Radiation at Extremes》 2026年第2期95-103,共9页
Light element compounds under high pressure display intriguing properties and applications,owing to their diverse bonding patterns and crystalline structures.However,the system of ternary Be-C-O compounds under high p... Light element compounds under high pressure display intriguing properties and applications,owing to their diverse bonding patterns and crystalline structures.However,the system of ternary Be-C-O compounds under high pressure,as the lightest representative of the IIA-IVA-VIA family,remains largely unexplored.Using a machine-learning-accelerated crystal structure search and first-principles calculations,Be-C-O phase diagrams are investigated at pressures ranging from 0 to 100 GPa.Four ternary compounds are proposed to be stable at corresponding pressures:BeCO_(3),Be_(2)CO_(4),Be_(2)C_(4)O_(3),and BeC_(4)O_(2).Analyses of electronic structure and chemical bonding further reveal how the structural diversity of these compounds is induced.Remarkably,Be_(2)C_(4)O_(3) and BeC_(4)O_(2) are recoverable to ambient conditions and possess both high energy density and high hardness.The volumetric energy densities of Be_(2)C_(4)O_(3) and BeC_(4)O_(2) could approach 9.03 and 7.94 kJ/cm^(3),respectively.The Vickers hardnesses of Be_(2)C_(4)O_(3) and BeC_(4)O_(2) are found to be close to 39.58 and 51.57 GPa,respectively.These findings demonstrate the structural and functional diversity of Be-C-O compounds under high pressure,providing guidance for further exploration of the IIA-IVA-VIA compounds. 展开更多
关键词 bonding patterns ternary compounds SUPERHARD high energy density crystal structure search light element compounds be c o compounds pressure induced
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Recent advances in the magnetism of layered transition-metal compoundsII.CLASSIFICATION AND MAGNETIC PROPERTIES OF LAYERED TRANSITION METAL COMPOUNDS
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作者 XU Jie ZHANG Yaling +5 位作者 LIU Xiaoxuan WANG Yuanyuan XUE Tingyuan GU Liang MAN Xiaoxiao ZHANG Huisheng 《物理学进展》 北大核心 2026年第2期51-71,共21页
Layered transition-metal compounds(LTMCs)feature stacked architectures,strong magnetic anisotropy,and tunable magnetic order,making them promising material platforms for low-power spintronic technologies and for enabl... Layered transition-metal compounds(LTMCs)feature stacked architectures,strong magnetic anisotropy,and tunable magnetic order,making them promising material platforms for low-power spintronic technologies and for enabling topological functionalities in the post-Moore era.Here we review recent progress on two-dimensional(2D)magnetism in LTMCs,emphasizing material taxonomy,intrinsic magnetic properties,and external-field controls.This review first presents a classification of LTMCs by crystal structure and chemistry—binary halides,chalcogenides,and ternary families(e.g.,MPX_(3),M_(m)X_(n)Te_(k),MnBi_(2)Te_(4))—followed by a summary of their coupling mechanisms,ordering temperatures,and dimensional effects.It then analyzes the modulation of exchange interactions,magnetic anisotropy,and topological states by electric-field gating,strain engineering,and ion intercalation,with representative experimental demonstrations.Notable advances include room-temperature ferromagnetic metals and semiconductors,observation of the quantum anomalous Hall effect(QAHE)in MnBi2Te4,and synergistic control of magnetic-topological states under multiple external stimuli.Persistent challenges involve the limited availability of intrinsic 2D magnetic semiconductors with high Curie temperatures(Tc),incomplete understanding of the microscopic couplings at interfaces and under quantum confinement,and device-level stability.We conclude by outlining opportunities that lie in the integration of multiscale characterization,first-principles theory,and cross-scale fabrication to precisely co-engineer magnetism,topology,and electronic structure,thereby advancing LTMCs toward spintronic and topological-quantum applications. 展开更多
关键词 layered transition-metal compounds two-dimensional magnetism electric-field control strain engineering ion intercalation topological magnetism quantum anomalous Hall effect
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Volatile Organic Compounds in Japonica Rice and Their Influence on Flavor Substances and Sensory Characteristics of Beer
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作者 BAI Yanlong TANG Zixuan +5 位作者 ZHOU Yin ZHU Dawei HU Xianqiao CHEN Mingxue QIU Ran SHAO Yafang 《Rice science》 2026年第2期168-172,I0073-I0080,共13页
To elucidate the variations in volatile organic compounds(VOCs)among widely cultivated japonica rice varieties in China and offer novel perspectives on flavor formation during rice-based beer brewing,nine prevalent Ch... To elucidate the variations in volatile organic compounds(VOCs)among widely cultivated japonica rice varieties in China and offer novel perspectives on flavor formation during rice-based beer brewing,nine prevalent Chinese japonica rice variaties were selected as experimental materials.Comprehensive analyses were conducted to investigate three key aspects:differences in VOCs among the selected japonica rice varieties,the retention of rice VOCs after beer brewing,and the influence of rice additives on beer sensory characteristics.Results showed that the total contents of VOCs in Wuyoudao 4(WYD4)and Nangeng 9108(NG9108)were significantly higher than those in the other varieties(P<0.05).The popcorn-flavor compound 2-acetyl-1-pyrroline(2-AP)was detected in Suigeng 27(SG27,26.80 ng/g),WYD4(25.25 ng/g),NG9108(21.18 ng/g),and Suigeng 18(SG18,11.62 ng/g),with the levels in the first three varieties significantly higher than those in SG18.Circular heatmap analysis classified the nine japonica varieties into three major categories:fragrant japonica from North China(WYD4),fragrant japonica from South China(NG9108),and others.Ten characteristic VOCs across the japonica varieties were identified by headspace solid-phase microextraction gas chromatography-mass spectrometry(HS-SPME-GC-MS).Using beer brewed with whole wheat as the control,we analyzed the VOCs and sensory characteristics of beer brewed with fragrant japonica rice as an additive.We found that rice VOCs were not detected in beer brewed with fragrant japonica rice as an additive.Adding rice promoted the formation of banana-like flavors and reduced the beer’s richness and mellowness. 展开更多
关键词 volatile organic compounds vocs rice additives beer sen volatile organic compounds beer brewing sensory characteristics japonica rice flavor formation
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Visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers
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作者 Feng Zhao Hongyu Ding +4 位作者 Ting Sun Chao Shen Zu-Li Wang Wei Wei Dong Yi 《Chinese Chemical Letters》 2026年第2期206-217,共12页
Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable ... Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable strategy for constructing new carbon-oxygen bonds.In comparison with traditional thermal or metal-mediated carbene transfer reactions,visible-light-promoted multi-component reaction strategy provides a mild and eco-friendly approach to access densely functionalized molecules.Recently,visible-light-induced multi-component carbene transfer reactions of diazo compounds have been rapidly developed and attracted a great deal of research interest of chemists owing to their advantages of simple operation,mild condition,high atom economy and rich structural diversity.This paper summarizes the recent research progress on the visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers with various nucleophiles.The reaction patterns of different nucleophiles and their corresponding mechanism are described in this review.The future research direction and challenges in this area are also discussed. 展开更多
关键词 VISIBLE-LIGHT Multi-component reaction Carbene insertion Diazo compounds Ring-opening reaction
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A novel compound heterozygous mutation in ADAMTS17 identified in a Chinese family with Weill-Marchesani syndrome
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作者 Hao-Yue Wu Si-Wei Liu +3 位作者 Zhao Liu Cheng Pei Chang-Rui Wu Shan Gao 《International Journal of Ophthalmology(English edition)》 2026年第2期239-246,共8页
AIM:To investigate the genetic basis of Weill-Marchesani syndrome(WMS)in a Chinese family and clarify the pathogenic mechanism of novel ADAMTS17 mutations.METHODS:Comprehensive clinical assessments and genetic analyse... AIM:To investigate the genetic basis of Weill-Marchesani syndrome(WMS)in a Chinese family and clarify the pathogenic mechanism of novel ADAMTS17 mutations.METHODS:Comprehensive clinical assessments and genetic analyses were performed on a Chinese family with two affected siblings.Whole-exome sequencing(WES)was conducted for the proband and other family members.Bioinformatics tools were used to evaluate the conservation,predicted pathogenicity,and structural effects of the identified ADAMTS17 variants.In addition,protein structure modeling was applied to assess the functional impacts of the mutations.RESULTS:The proband(a 32-year-old male)and his elder sister(42y)presented typical clinical features of WMS,including short stature,brachydactyly,high myopia,ectopia lentis,and secondary glaucoma.WES identified a novel compound heterozygous mutation in ADAMTS17:a splicing mutation(c.451-2A>G)inherited from the father and a missense mutation(c.1043G>A;p.C348Y)inherited from the mother.The splicing mutation disrupted normal mRNA splicing and processing,leading to premature translation termination.The missense mutation,which is located in the metalloprotease catalytic domain,was predicted to abolish a critical disulfide bond,thereby impairing protein stability.Both mutations exhibited high evolutionary conservation and were predicted to be pathogenic by multiple bioinformatics algorithms.CONCLUSION:A novel compound heterozygous mutation in ADAMTS17 is identified in this WMS-affected Chinese family,and its pathogenicity is verified via bioinformatics analysis and protein structural modeling.These findings are expected to facilitate the genetic diagnosis of WMS and deepen the understanding of its molecular pathogenesis. 展开更多
关键词 Weill-Marchesani syndrome ADAMTS17 compound heterozygous mutation molecular genetics BIOINFORMATICS
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Impact of temperature on the biogenic volatile organic compound(BVOC)emissions in China:A review
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作者 Yiming Yang Fengbin Sun +8 位作者 Yusheng Chen Shiyue Yang Yuan Dai Yiming Qin Ning Zhang Zhifeng Shu Han Yan Xinlei Ge Junfeng Wang 《Journal of Environmental Sciences》 2026年第1期649-660,共12页
Temperature has a substantial impact on the emission of biogenic volatile organic compounds(BVOCs).Moder-ate warm temperatures,e.g.,30–40°C,could boost plant metabolism,increasing BVOC emissions.Against the back... Temperature has a substantial impact on the emission of biogenic volatile organic compounds(BVOCs).Moder-ate warm temperatures,e.g.,30–40°C,could boost plant metabolism,increasing BVOC emissions.Against the backdrop of global warming,plants emit more BVOCs to cope with thermal stress,leading to elevated concen-trations of tropospheric ozone(O_(3))and secondary organic aerosols(SOA).In recent years,a considerable body of research has explored the interaction between tree species and BVOCs under the influence of various environ-mental factors.Although many studies have examined explored the temperature dependence of BVOC emissions in the past,few studies have conducted a comprehensive and in-depth investigation into the impacts of tempera-ture.This review summarizes the relevant studies on BVOCs in the past decade,including the main biosynthetic pathways,emission observation techniques and emission inventories,as well as how temperature affects isoprene and monoterpene emission rates and the formation of O_(3) and SOA.Our work offers a theoretical foundation and guidance for future efforts to advance the comprehension of BVOC emission characteristics and develop strategies to mitigate secondary pollution. 展开更多
关键词 TEMPERATURE Biogenic volatile organic compounds ISOPRENE OZONE Secondary organic aerosol
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Insights from untargeted metabolomics:revealing potential marker compounds in the maturation of fermented chili
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作者 Shiyu Liu Mingyuan Yang +6 位作者 Jianhua Zhao Meijuan Lei Jinlin Han Min Xu Ping Liu Jie Tang Hongbin Lin 《Food Science and Human Wellness》 2026年第1期228-238,共11页
Chili fermentation is one of the most important processes in the production of Pixian Douban(PXDB),which determines the flavor and product quality of PXDB.However,the maturity of fermented chili mainly depends on empi... Chili fermentation is one of the most important processes in the production of Pixian Douban(PXDB),which determines the flavor and product quality of PXDB.However,the maturity of fermented chili mainly depends on empirical judgment,which can not satisfy the need for standardized production of PXDB.Therefore,this study aimed to investigate volatile and non-volatile substances during the maturation process and to find markers related to the maturity of fermented chili.Two-dimensional gas chromatography-mass spectrometry(GC×GC-MS)combined with multivariate statistical analysis and relative odor activity values(ROAV)analysis revealed that 2-methoxy-3-isobutyl pyrazine,linalool,3-(methylthio)propionaldehyde,myrcene,and decanal(ROAV≥1,VIP>1,P<0.05)were regarded as potentially active aromatic markers for differentiating fermentation time.Additionally,ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLCQTOF-MS)combined with multivariate statistical analysis revealed that 25 compounds could serve as differentiated non-volatile compounds.The correlation of maturity-related physicochemical indicators with volatile and nonvolatile compounds revealed that four volatile compounds(2-methoxy-3-isobutylpyrazine,linalool,myrcene,and decanal)along with seven non-volatile compounds could serve as markers for evaluating the maturity of fermented chili.This study is expected to establish a standard for the determination of the maturity the fermented chili and lay the foundation for intelligent production of PXDB. 展开更多
关键词 Fermented chili Mature standards Volatile substances Non-volatile compounds Multivariate statistical analysis
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Constructing a high-performance magnesium single-atom catalyst for the transfer hydrogenation of biomass-derived carbonyl compounds in ethanol
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作者 Lei Hu Mengxue Liu +5 位作者 Baogang Sha Jiacheng Li Aiyong He Xing Tang Zhen Wu Lu Lin 《Journal of Energy Chemistry》 2026年第1期517-531,I0012,共16页
Endogenous hydrogen systems,consisting of metal–organic coordination catalysts and alcohols,have been widely applied for the transfer hydrogenation(TH)of biomass-derived carbonyl compounds in recent years.Metal-organ... Endogenous hydrogen systems,consisting of metal–organic coordination catalysts and alcohols,have been widely applied for the transfer hydrogenation(TH)of biomass-derived carbonyl compounds in recent years.Metal-organic coordination catalysts showed satisfactory ability of TH in the secondary alcohols,but most of them could not effectively employ the cheaper primary alcohols as hydrogen donors.Furthermore,they commonly contained high metal contents,which also led to low catalytic efficiency in significant measure.In this work,we constructed a novel magnesium single-atom catalyst(Mg-NC)with merely 0.37 wt%Mg by means of a combined self-assembly and pyrolysis strategy.The characterization results indicated that Mg was atomically dispersed and it was coordinated with four pyridinic-N in Mg-NC.Due to the obvious electron transfer from Mg to its coordinated pyridinic-N,Mg–N_(4)active centers displayed high Lewis acid-base strength with abundant content,which brought remarkable catalytic activity.When Mg-NC was used for the TH of 5-hydroxymethylfurfural(HMF)in ethanol(EtOH),2,5-bis(hydroxymethyl)furan(BHMF)yield was up to 96.3%with high productivity of 19.85 molBHMF mol_(Mg)^(−1)h^(−1)at 150°C for 5 h.More interestingly,the process of TH over Mg-NC in EtOH was proved to proceed via the hydrogen radical mechanism.Additionally,Mg-NC exhibited powerful catalytic universality;it could not only utilize other primary alcohols(such as n-propanol and n-butanol)as hydrogen donors,but also catalyze the TH of other carbonyl compounds(such as furfural,5-methylfurfural,benzaldehyde,cyclohexanone,and levulinic acid).Overall,this work offered some important clues and references to reinforce the hydrogen-supplying ability of primary alcohols in the TH of various biomass-derived carbonyl compounds to high-value fine chemicals. 展开更多
关键词 Transfer hydrogenation Carbonyl compounds Primary alcohols Single-atom catalysts Lewis acid-base sites Synergistic effects
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Intervention effect and mechanism of Compound Herba Gueldenstaedtiae in a mouse model of breast hyperplasia
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作者 Wu Yilin Tian Hongying +8 位作者 Sun Jiale Jiao Jiajia Zhao Zihan Shao Jinhuan Zhao Kaiyue Zhou Min Li Qian Li Zexin Yue Changwu 《中国组织工程研究》 北大核心 2026年第17期4377-4389,共13页
BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probi... BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probiotics have shown good potential in regulating the endocrine system and improving the intestinal microecology,providing new ideas for the treatment of breast hyperplasia.OBJECTIVE:To explore the effects and mechanisms of traditional Chinese medicine compounds and fermented probiotic compounds on breast hyperplasia in mice,providing new theoretical and experimental bases for the clinical treatment and prevention of breast hyperplasia.METHODS:(1)Network pharmacology tools were used to predict the anti-breast-hyperplasia activity of Herba Gueldenstaedtiae(Euphorbia humifusa),as well as its potential targets and signaling pathways.The databases included:TCMSP,OMIM,GeneCards database,UniProt website,Venny2.1.0 website,Metascape,HERB website,and STRING database,all of which are open-access databases.Network pharmacology can predict and screen key information such as the targets corresponding to the active ingredients of traditional Chinese medicine,disease targets,and action pathways through network analysis and computer-system analysis.Therefore,it has been increasingly widely used in the research of traditional Chinese medicine.(2)A breast hyperplasia model was induced in mice by injecting estrogen and progesterone.Mice in the normal blank group were injected intraperitoneally with normal saline every day.Mice in the model group and drugadministration groups were injected intraperitoneally with estradiol benzoate injection at a concentration of 0.5 mg/kg every day for 25 days.From the 26th day,the injection of estradiol benzoate injection was stopped.Mice in the normal blank group were injected intramuscularly with normal saline every day,and mice in the model group and drug-administration groups were injected intramuscularly with progesterone injection at a concentration of 5 mg/kg for 5 days.After the model was established,each group was given drugs respectively.The normal blank group and the model group were gavaged with 0.2 mL/d of normal saline;the positive blank group(Xiaozheng Pill group)was gavaged with an aqueous solution of Xiaozheng Pill at 0.9 mg/g;the low-,medium-and high-dose groups of Compound Herba Gueldenstaedtiae were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively;the low-,medium-and high-dose groups of traditional Chinese medicine-bacteria fermentation were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively.The administration was continuous for 30 days.RESULTS AND CONCLUSION:(1)The results of network pharmacology research showed that the Compound Herba Gueldenstaedtiae(Euphorbia humifusa)contained 46 active ingredients,which were related to 1213 potential targets.After comparison with 588 known breast-hyperplasia targets,it was speculated that 50 of these targets might be related to the direct effect of the compound on breast hyperplasia.(2)After drug intervention,there was no significant change in the high-dose group of Compound Herba Gueldenstaedtiae compared with the normal blank group.The liver indicators of the other intervention groups all significantly decreased(P<0.05).(3)In terms of kidney and uterine indicators,the medium-dose group of Compound Herba Gueldenstaedtiae decreased significantly compared with the normal blank group(P<0.05).In terms of the uterine index,the model group increased significantly compared with the normal blank group(P<0.01).(4)After 1-month drug treatment,the number of lobules and acini in the breast tissue of the Xiaozheng Pill group,the low,medium,and high-dose group of Compound Herba Gueldenstaedtiae,the low,medium,and highdose groups of traditional Chinese medicine-bacteria fermentation decreased,and the duct openings narrowed.With the increase of drug dose,diffuse hyperplasia of breast tissue was significantly improved.(5)The ELISA results showed that compared with the model group,the estrogen level was lower in the medium-dose group of traditional Chinese medicine-bacteria fermentation after the intervention(P<0.05).In addition,the follicle-stimulating hormone level in the low-dose group of Compound Herba Gueldenstaedtiae was lower than that of the model group(P<0.05).(6)The intervention in the mouse model led to changes in the abundance of short chain fatty acids and intestinal flora in all groups.To conclude,the Compound Herba Gueldenstaedtiae and its probiotic fermentation products significantly improved mammary gland hyperplasia in mice by regulating hormone levels,improving the structure of the gut microbiota,and increasing the content of shortchain fatty acids,providing new ideas and potential sources of drugs for the treatment of breast hyperplasia. 展开更多
关键词 Herba Gueldenstaedtiae traditional Chinese medicine compound mice with breast hyperplasia microbial fermentation gut microbiota network pharmacology short-chain fatty acids hormone levels inflammatory response endocrine disorders
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OSCJC:An open-set compound jamming cognition method for radar systems in high-intensity electromagnetic warfare
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作者 Kaixiang Zhang Jiaxiang Zhang +3 位作者 Xinrui Han Yilin Wang Bo Wang Quanhua Liu 《Defence Technology(防务技术)》 2026年第1期436-455,共20页
In high-intensity electromagnetic warfare,radar systems are persistently subjected to multi-jammer attacks,including potentially novel unknown jamming types that may emerge exclusively under wartime conditions.These j... In high-intensity electromagnetic warfare,radar systems are persistently subjected to multi-jammer attacks,including potentially novel unknown jamming types that may emerge exclusively under wartime conditions.These jamming signals severely degrade radar detection performance.Precise recognition of these unknown and compound jamming signals is critical to enhancing the anti-jamming capabilities and overall reliability of radar systems.To address this challenge,this article proposes a novel open-set compound jamming cognition(OSCJC)method.The proposed method employs a detection-classification dual-network architecture,which not only overcomes the false alarm and misdetection issues of traditional closed-set recognition methods when dealing with unknown jamming but also effectively addresses the performance bottleneck of existing open-set recognition techniques focusing on single jamming scenarios in compound jamming environments.To achieve unknown jamming detection,we first employ a consistency labeling strategy to train the detection network using diverse known jamming samples.This strategy enables the network to acquire highly generalizable jamming features,thereby accurately localizing candidate regions for individual jamming components within compound jamming.Subsequently,we introduce contrastive learning to optimize the classification network,significantly enhancing both intra-class clustering and inter-class separability in the jamming feature space.This method not only improves the recognition accuracy of the classification network for known jamming types but also enhances its sensitivity to unknown jamming types.Simulations and experimental data are used to verify the effectiveness of the proposed OSCJC method.Compared with the state-of-the-art open-set recognition methods,the proposed method demonstrates superior recognition accuracy and enhanced environmental adaptability. 展开更多
关键词 Radar compound jamming cognition Open-set recognition Detection-classification dual-network Time-frequency analysis Contrastive learning
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A sensitive method for rapid determination of 256 semi-volatile organic compounds(SVOCs)in water by solid-phase extraction and GC-MS/MS
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作者 Youchang Zhu Ruohan Sun +5 位作者 Yanran Dong Yan Liu Yupeng Chen Zhiquan Yuan Baozhu Pan Nan Xu 《Journal of Environmental Sciences》 2026年第1期362-373,共12页
A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 pol... A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 polycyclic aromatic hydrocarbons(PAHs),70 polychlorinated biphenyls(PCBs),123 pesticides,20 phthalate esters(PAEs),4 organophosphate esters(OPEs),9 synthetic musks(SMs),and 5 UV filters(UVs)in water.No-tably,this method provided a decent linearity of calibration standards(R^(2)>0.999),excellent method limits of quantification(MLOQs)(0.12–11.41 ng/L),satisfactory matrix spiking recovery rates(60.4%–126%),and high precision(intra-day relative standard deviations(RSDs):1.0%–10.0%,inter-day RSDs:3.0%–15.0%,and inter-week RSDs:3.4%–15.7%),making it suitable for trace-level studies.Statistical analysis revealed that SVOCs with higher volatility exhibited enhanced recovery rates.Validation of the methodology involved analyzing SVOCs in real spring water and river water samples.Twenty-seven SVOCs were detected in spring water and 58 in river water,with an average concentration of 631.73 and 16,095 ng/L,respectively.Among the detected SVOCs,PAEs constituted the predominant proportion.This study underscored the presence of SVOCs contamination specifi-cally within the spring water,although SVOCs concentrations in river water were significantly greater than those found in spring water.In summary,this sensitive method based on SPE–GC–MS/MS was successfully developed and validated for the rapid analysis of a diverse array of 256 SVOCs at trace levels in water,including not only the traditional highly valued PAHs,PCBs,pesticides,and PAEs,but also the emerging OPEs,UVs,and SMs. 展开更多
关键词 Semi-volatile organic compounds Spring water GC-MS/MS Organophosphate esters Synthetic musks UV filters
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Algae penetration and taste and odor compounds production in drinking water treatment plants:seasonal variations and risk assessment
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作者 Ya Cheng Caiyun Ma +5 位作者 Gang Wen Chaoyang Zheng Wenle Tian Kailin Sha Xinru Han Tinglin Huang 《Journal of Environmental Sciences》 2026年第2期319-329,共11页
In the conventional water treatment process,algae have a propensity to breach the filter barriers and potentially seep into the water distribution system,leading to an elevation in taste and odor compounds(T&O com... In the conventional water treatment process,algae have a propensity to breach the filter barriers and potentially seep into the water distribution system,leading to an elevation in taste and odor compounds(T&O compounds).This investigation delved into the seasonal fluctuations of algae penetration and the production of T&O compounds within the treatment units of Reservoir Water Plant 1(W1)and River Water Plant 2(W2).The findings indicated that despite the application of the‘pre-oxidation,coagulation and sedimentation(PCS),sand filtration,and disinfection’process,certain robust-walled filamentous Cyanobacteria,Bacillariophyta species,and small Chlorophyta genera managed to bypass the filters.The leakage of algal cells during autumn at W1 was particularly striking,with a peak of 1,170,000 cells/L.The concurrent assessment of the potential for T&O compound formation revealed an alarming high potential for 2-methylisoborneol(2-MIB)in the water leaving the plants,with concentrations soaring to 197.20 ng/L at W1 in autumn and 54.78 ng/L at W2 in summer.This underscores the significant capacity of residual algal cells to generate T&O compounds.Tracking the retention and penetration dynamics of algal cells across each drinking water treatment stage is crucial for surface water treatment facilities to develop effective operational and management strategies,thereby enhancing the safety and quality of drinking water for the end consumer. 展开更多
关键词 CYANOBACTERIA Surface water treatment plant Algae penetration Taste and odor compounds 2-METHYLISOBORNEOL
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Characterization,sources and reactivity of carbonyl volatile organic compounds in North China:Based on long-term observations
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作者 Ziyan Chen Kaitao Chen +4 位作者 Xingru Li Rongjie Li Zheng Li Bingyu Xiao Gehui Wang 《Journal of Environmental Sciences》 2026年第1期797-808,共12页
Carbonyl compounds play a pivotal role in the formation of secondary pollutants such as O_(3) and SOA,signifi-cantly impacting air quality and human health.This study extended the observation period compared to previo... Carbonyl compounds play a pivotal role in the formation of secondary pollutants such as O_(3) and SOA,signifi-cantly impacting air quality and human health.This study extended the observation period compared to previous research,providing a long-term perspective on carbonyl compound variations and their environmental implica-tions.Atmospheric observations were conducted at Beijing(BJ)and Xianghe(XH)during the summer and winter months of 2018,2019,and 2023 to study the sources and impacts of carbonyl compounds in typical urban areas and peri‑urban areas.Notably,concentrations in the summer of 2023 increased compared to 2018 and 2019.The predominant carbonyl compounds—formaldehyde,acetaldehyde,and acetone—accounted for over 60%of the total.The mean values of OFP in BJ ranged from 18.55 to 58.61μg/m3,lower than those in XH(29.82 to 65.48μg/m3),with formaldehyde and acetaldehyde contributing over 80%of the total.SOAP exhibited a similar pattern,with values in XH(69.21 to 508.55μg/m3)significantly exceeding those in BJ(34.47 to 159.78μg/m3).The PMF model highlighted vehicle exhaust,secondary pollution,and biomass combustion as major sources of carbonyl compounds,emphasizing differences in source contributions between the two regions.This study’s com-parative analysis over different years and locations provides new insights into the dynamic changes in carbonyl compounds and their environmental importance.These results not only reinforce the importance of carbonyl compounds regulation but also offer a valuable reference for evaluating and refining emission control strategies during this period. 展开更多
关键词 Carbonyl compounds Ozone formation potential Secondary organic aerosol formation potential Source resolution
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Ex vivo to in vivo extrapolation of primary absorbed compounds as multifunctional proxies of Zhiqiao(Fructus Aurantii Submaturus)-Houpo(Cortex Magnoliae Officinalis)herb pair
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作者 ZHOU Runze XU Chendong +1 位作者 QIAN Haotian HUANG Xi 《Journal of Traditional Chinese Medicine》 2026年第1期51-61,共11页
OBJECTIVE:To eliminate ineffective or interfering compounds from the eight absorbed compounds(8ACs),identify the primary ACs that represent the multifunctional therapeutic effects of Zhiqiao(Fructus Aurantii Submaturu... OBJECTIVE:To eliminate ineffective or interfering compounds from the eight absorbed compounds(8ACs),identify the primary ACs that represent the multifunctional therapeutic effects of Zhiqiao(Fructus Aurantii Submaturus)and Houpo(Cortex Magnoliae Officinalis)(FM),along with elucidating their underlying mechanisms.METHODS:Key multifunctional ACs were screened through ex vivo-to-in vitro extrapolation(ex vivo dose=serum concentration)and validated in vivo,with efficacy assessed via contribution(dose=FM content).Functional magnetic resonance imaging analyzed brain regions's blood oxygen level-dependent(BOLD)changes,and the molecular mechanisms were analyzed by transcriptome of the dentate gyrus(DG).RESULTS:The results showed that representative 2ACs(Nobiletin+Magnolol)and 3ACs(Nobiletin+Magnolol+Meranzin hydrate)screened on ex vivo experiment by the criteria of contribution ranking contributed 80.72%-126.74%of the antidepressant and prokinetic effects of the FM(improvement of depressive-like behaviours,gastrointestinal disorder,monoamine neurotransmitters,ghrelin,endocrine hormones,pro-inflammatory factors,oxidative stress indicators).In addition,3ACs demonstrated superiority over 2ACs in improving depression and levels of multiple stress mediators.Zhiqiao(Fructus Aurantii Submaturus)(FRA)reduced acute stress-induced hyperactivation of the cingulate cortex,thalamus,hypothalamus,and entorhinal cortex and elevated BOLD signaling in the insular cortex,temporal association cortex.Furthermore,FRA upregulated pathways of neurotransmitter receptor activity and serotonergic synaptic function and downregulated inflammation-related pathways at the genetic level.CONCLUSION:2ACs and 3ACs closely reflected FM's multifunctional effect in antidepressant and prokinetic.FRA restores stress-impaired neural connectivity in functional brain regions and improves synaptic plasticity and neurogenesis at the genetic level. 展开更多
关键词 Zhiqiao(Fructus Aurantii Submaturus) Houpo(Cortex Magnoliae Officinalis) multifunctional absorbed compounds NOBILETIN MAGNOLOL meranzin hydrate
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Design of hydrogen-liquefied magnetic refrigeration materials by elemental regulation in RE_(3-x)HoxB_(0.5)C_(3.5)(RE=Dy,Tb)compounds
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作者 Haobo Sun Lu Tian +4 位作者 Jianjian Gong Zhenxing Li Zhaojun Mo Guodong Liu Jun Shen 《Journal of Rare Earths》 2026年第3期850-859,I0005,共11页
The search for high-abundance compounds containing rare earth elements to develop high-performance magnetic refrigeration materials for hydrogen liquefaction has become a particularly attractive research direction.We ... The search for high-abundance compounds containing rare earth elements to develop high-performance magnetic refrigeration materials for hydrogen liquefaction has become a particularly attractive research direction.We successfully manipulated the magnetic interactions in tetragonal rare earth carbides(RE_(3)C_(4))by doping them with boron(B)element,transforming their state from antiferromagnetic to ferromagnetic.Theoretical calculations and experimental results indicate that the transition in magnetic interactions may be due to the synergistic effects of electronic structure and lattice distortions.Building on this,further doping with holmium(Ho)element was used to adjust the magnetic transition temperature of the system.The results show that the magnetic transition temperature of this series of compounds can be effectively altered within the range of 26-42.8 K.By optimizing the composition of rare earth elements,a series of novel candidate materials exhibiting significant magnetocaloric effects within the temperature range required for hydrogen liquefaction is successfully developed. 展开更多
关键词 Liquid hydrogen RE_(3)C_(4)compounds Magnetocaloric effects Ferromagnetic state Rare earths
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Realizing Stable Zigzag Polymeric Nitrogen Chains in P-N Compounds
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作者 Chengfeng Zhang Guo Chen +2 位作者 Yanfeng Zhang Jie Zhang Xianlong Wang 《Chinese Physics Letters》 2026年第3期316-330,共15页
The zigzag nitrogen chain,similar to the Ch-N structure,has long been considered as a potential high-energy-density structure.However,all the previously predicted zigzag N-chain structures,similar to Ch-N,exhibited im... The zigzag nitrogen chain,similar to the Ch-N structure,has long been considered as a potential high-energy-density structure.However,all the previously predicted zigzag N-chain structures,similar to Ch-N,exhibited imaginary frequencies in their phonon spectra at 0 GPa.Here,we conducted a systematic investigation of P-N compounds using first-principles calculations,uncovering a series of structurally similar stable phases,C2/m-PN_(x)(x=6,8,10,12,and 14),in which N forms zigzag N chains similar to those in Ch-N.In P-N compounds,the longest zigzag N-chain,which can theoretically remain stable under ambient pressure,is the N-chain composed of 14 N atoms in C2/m-PN14.If the N-chain continues to grow,imaginary interchain vibrational frequencies arise in the system.Notably,N chains with an even number of atoms were more likely to be energetically favorable.The five C2/m-PN_(x) phases and one metastable phase(R-PN_(6))exhibited remarkable stability and excellent detonability at ambient pressure,indicating that they are promising candidates for high-energy-density materials.In addition,R-PN_(6) was the first structure to stabilize the N_(6) ring through covalent bonding,with the covalent network contributing to its high hardness(47.59 GPa). 展开更多
关键词 p n compounds phonon spectra imaginary frequencies high energy density materials zigzag n chains zigzag nitrogen chainsimilar stable zigzag polymeric nitrogen chains first principles calculations
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Complexation with pre-formed“empty”V-type starch for encapsulation of aroma compounds 被引量:2
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作者 Jingyi Zhou Lingyan Kong 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期488-494,共7页
Aroma compounds are low-molecular-weight organic volatile molecules and are broadly utilized in the food industry.However,due to their high volatility and evaporative losses during processing and storage,the stabiliza... Aroma compounds are low-molecular-weight organic volatile molecules and are broadly utilized in the food industry.However,due to their high volatility and evaporative losses during processing and storage,the stabilization of these volatile ingredients using encapsulation is a commonly investigated practice.Complexation of aroma compounds using starch inclusion complex could be a potential approach due to the hydrophobicity of the left-handed single helical structure.In the present study,we used starch of three different V-type structures,namely V,V,and V,to encapsulate six different aroma compounds,including1-decanol(DN),cis-3-hexen-1-ol(HN),4-allylanisole(AN),γ-decalactone(DA),trans-cinnamaldehyde(CA),and citral(CT).The formed inclusion complexes samples were characterized using complementary techniques,including X-ray diffraction(XRD)and differential scanning calorimetry(DSC).The results showed that upon complexation with aroma compounds,all V-subtypes retained their original crystalline structures.However,different trends of crystallinity were observed for each type of the prepared inclusion complexes.Additionally,among three V-type starches,V-type starch formed inclusion complexes with aroma compounds most efficiently and promoted the formation of FormⅡcomplex.This study suggested that the structure of aroma compounds and the type of V starch could both affect the complexation properties. 展开更多
关键词 STARCH “Empty”v-type AROMA Inclusion complex ENCAPSULATION
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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:3
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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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New Exact Traveling Wave Solutions for Compound KdV-Type Equation with Nonlinear Terms of Any Order 被引量:1
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作者 DU Xing-Hua LIU Cheng-Shi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期787-792,共6页
The compound KdV-type equation with nonlinear terms of any order is reduced to the integral form. Using the complete discrimination system for polynomial, its all possible exact traveling wave solutions are obtained. ... The compound KdV-type equation with nonlinear terms of any order is reduced to the integral form. Using the complete discrimination system for polynomial, its all possible exact traveling wave solutions are obtained. Among those, a lot of solutions are new. 展开更多
关键词 compound Kdv-type equation complete discrimination system for polynomial traveling wavesolution evolution equation
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