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Novel Method for Preparation of Polypropylene Blends with High Melt Strength by Reactive Compounding 被引量:2
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作者 LIU Yu-guang HUANG Yu-dong +2 位作者 ZHANG Cheng-wu HOU Jing ZHANG Xue-quan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第4期569-572,共4页
Ultrafine full-vulcanized polybutadiene rubber(UFBR) with particle sizes of ca.50―100 nm were used for modifying mechanical and processing performances of polypropylene(PP) with PP-g-maleic anhydride(PP-g-MA) a... Ultrafine full-vulcanized polybutadiene rubber(UFBR) with particle sizes of ca.50―100 nm were used for modifying mechanical and processing performances of polypropylene(PP) with PP-g-maleic anhydride(PP-g-MA) as a compatibilizer for enhancing the interfacial adhesion between the two components.The morphology,dynamical rheology response and mechanical properties of the blends were characterized by means of SEM,rheometer and tensile test,respectively.The results show that the ternary PP/UFBR blends compatibilized with PP-g-MA possess rheological behaviors like highly branched PP,while no obvious strain hardening is observed in its control binary PP/UFBR blends,a low level of PP-g-MA in PP/UFBR blends can even endow the material with rheological characteristics of high melt strength materials like highly branched PP.The enhancement interfacial interaction between the UFBR particles and PP matrix accounting for the rheological behavior of compatibilized blends and effectiveness of PP-g-MA were proposed and proved. 展开更多
关键词 POLYPROPYLENE High melt strength Reactive compounding NANOPARTICLE RHEOLOGY
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Compounding Pattern of REE, Clay and Humic Acid in the Weathering Crust of Granites
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作者 陈炳辉 陈志澄 +3 位作者 梁群优 符群策 俞受鋆 张丽洁 《Journal of Rare Earths》 SCIE EI CAS CSCD 1996年第1期47-53,共7页
An anomalous phase containing clays and humic acid was found while extraction humic acid from samples of weathering crust of REE-bearing granites by using 0.1 mol/L NaOH solution.Studied by chemical separation experim... An anomalous phase containing clays and humic acid was found while extraction humic acid from samples of weathering crust of REE-bearing granites by using 0.1 mol/L NaOH solution.Studied by chemical separation experiments,column chromatography,ion-exchange chromatography,infrared spectrum.fluorescence spectrum,polarimicroscopic testing and elemental determination by ultraviolet-visible spectrometer and atomic absorption spectrometer.it was proved to be a compound of humic acid and clays which are connected in the form of bridge by heteronuclearpolynuclear complexing ions formed by cations of RE ̄(5+),Al ̄(3+).Fe ̄(3+) etc.The compounding pattern was further proved by the experiment for compounding humic acid,REE and kaolinite. 展开更多
关键词 REE Clays Humic acid compounding pattern Weathering crust of granites
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Optimization of ultrasonic elastography by coded excitation and transmit-side multi-frequency compounding
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作者 张志宏 刘昊霖 +1 位作者 何颖妮 刘东权 《Journal of Central South University》 SCIE EI CAS 2014年第3期1003-1010,共8页
To improve the quality of ultrasonic elastography, by taking the advantage of code excitation and frequency compounding, a transmitting-side multi-frequency with coded excitation for elastography (TFCCE) was propose... To improve the quality of ultrasonic elastography, by taking the advantage of code excitation and frequency compounding, a transmitting-side multi-frequency with coded excitation for elastography (TFCCE) was proposed. TFCCE adopts the chirp signal excitation scheme and strikes a balance in the selection of sub-signal bandwidth, the bandwidth overlap and the number of sub-strain image based on theoretical derivation, so as to further improve the quality of elastic image. Experiments have proved that, compared with the other optimizing methods, the elastographyic signal-to-noise ratio(Re-SN) and contrast-to-noise ratio(Re-CN) are improved significantly with different echo signal-to-noise ratios (ReSN) and attenuation coefficients. When ReSN is 50 dB, compared with short pulse, Rc-SN and Re-CN obtained by TFCCE increase by 53% and 143%, respectively. Moreover, in a deeper investigation (85-95 mm), the image has lower strain noise and clear details. When the attenuation coefficient is in the range of 0-1 dB/(cm.MHz), Re-SN and Re-CN obtained by TFCCE can be kept in moderate ranges of 5〈Re-SN〈6.8 and 11.4〈Re-CN〈15.2, respectively. In particular, for higher tissue attenuation, the basic image quality cannot be ensured with short pulse excitation, while mediocre quality strain figure can be obtained by TFCCE. Therefore, the TFCCE technology can effectively improve the elastography quality and can be applied to ultrasonic clinical trials. 展开更多
关键词 ultrasonic elastography coded excitation transmit-side multi-frequency compounding elastographyic signal-to-noise ratio echo signal-to-noise ratio contrast-to-noise ratio
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Effects of Different Compounding of Formulae on Content of Gardenoside in Yin Chen Hao Decoction
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作者 梁光义 曹佩雪 +3 位作者 柴立 冼福荣 李霞 王友京 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2002年第1期55-60,共6页
In order to observe the effects of the ground and intact Zhi Zi (Fructus Gardeniae) and different combinations of the ingredients and refined single Chinese drug granules in Yin Chen Hao Decoction compound prescriptio... In order to observe the effects of the ground and intact Zhi Zi (Fructus Gardeniae) and different combinations of the ingredients and refined single Chinese drug granules in Yin Chen Hao Decoction compound prescription on the contents of gardenoside (an effective component of the prescription), the contents of gardenoside were determined with reversed phase high performance liquid chromatography (HPLC), with acetonitrile-water (15:85) as mobile phase, at wave length 238nm. The results indicated that the gardenoside-decocted-out rates in the decoctions prepared by different combinations of the ingredients with the ground Zhi Zi (Fructus Gardeniae) all were higher significantly than those in the decoction with intact Zhi Zi (Fructus Gardeniae), and generally, different combinations of the ingredients in the decoction had only little effect on the gardenoside-decocted-out rate. 展开更多
关键词 IRIDOIDS Chromatography High Pressure Liquid Comparative Study Drug compounding Drugs Chinese Herbal PYRANS Technology Pharmaceutical
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Optimization Analysis of Correction Tape Box Compounding Cavity Runner Balance Based on Moldflow
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作者 Hongbing Wang Chunhua Sun 《World Journal of Engineering and Technology》 2020年第1期42-49,共8页
Aiming at the problem of runner unbalance in the compounding cavity of the upper and lower cover of the correction tape box, the plastic injection analysis software Moldflow was used to optimize runner balance. First,... Aiming at the problem of runner unbalance in the compounding cavity of the upper and lower cover of the correction tape box, the plastic injection analysis software Moldflow was used to optimize runner balance. First, the 3D modeling software Proe was used to establish the geometric model of the upper and lower cover of the correction tape box, and introduced into the plastic injection analysis software Moldflow. Secondly, the upper and the lower cover of the correction tape box were meshed and the initial gating system was designed in Moldflow. Filling analysis of the initial scheme of the correction tape box combined cavity showed that the runner of the melt was not balanced in the mold cavity. Finally, the runner balance optimization analysis of the cavities was carried out. Through optimization, the time unbalance rate of the melt in the mold cavity decreased from 28.6% to 0.7%, the pressure unbalance rate decreased from 42.0% to 4.2%, and the pressure distribution in the cavity was more uniform in the whole injection process. 展开更多
关键词 compounding CAVITY RUNNER BALANCE Optimization
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A Morphological Compounding Analysis of Hausa Registers Use in Nigerian Cell-phone Market
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作者 Almustapha Wali Sambo 《宏观语言学》 2020年第1期139-150,共12页
This study aims to find the compound registers that are used among the Farm-Centre cell-phone marketers,analyse their compounding morphological structures,and explain the meaning they convey.The Farm-Centre Cell-phone... This study aims to find the compound registers that are used among the Farm-Centre cell-phone marketers,analyse their compounding morphological structures,and explain the meaning they convey.The Farm-Centre Cell-phone Market is located in Kano metropolis,the largest city of Northern Nigeria.The study employs an ethnographic method of data collection and adopts Abubakar(2000)as a model of approach when analysing the structures of the compound registers.It is found that the registers have the following six morphological compound structures:(i)Genitive-based compounds[LG+N]N,(ii)Noun-based compounds[N+GL+N]N,(iii)Adjective-based compounds[Adj+N]N,(iv)Diminutive-based compounds[Dim+N]N,(v)Particle dà‘with’compounds[dà+N]N,(vi)Verb-based compounds[V+VN/Prep]V.Moreover,the registers are so special among the marketers because they convey meanings that are irrelevant to the conventional meanings known by the general speakers of the Hausa language. 展开更多
关键词 Hausa morphology compounding REGISTERS MEANING Kano NIGERIA
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赢创和Compounding Solutions LLC签订了一项医用级聚合物的分销协议
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《环球聚氨酯》 2018年第12期20-20,共1页
赢创公司已与全球领先的定制医疗塑料配制和分销公司Compounding Solutions LLC签署了一项协议,用于销售其VESTAMID?Care ML聚酰胺12, VESTAMID?Care ME聚醚嵌段酰胺(PEBA), TROGAMID?Care clear聚酰胺,和VESTAKEEP?Care PEEK医用级聚合... 赢创公司已与全球领先的定制医疗塑料配制和分销公司Compounding Solutions LLC签署了一项协议,用于销售其VESTAMID?Care ML聚酰胺12, VESTAMID?Care ME聚醚嵌段酰胺(PEBA), TROGAMID?Care clear聚酰胺,和VESTAKEEP?Care PEEK医用级聚合物,在北美临时接触(体内<30天)医疗器械市场上销售。 展开更多
关键词 高性能聚合物 compounding SOLUTIONS LLC 医用级
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Derivation Versus Compounding
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作者 陈雅荃 《海外英语》 2019年第24期117-118,共2页
In English language,affixation is a significant way of forming new words,This essay intends to explore the concepts of two fundamental ways of forming new words,namely,derivation and compounding.They are different in ... In English language,affixation is a significant way of forming new words,This essay intends to explore the concepts of two fundamental ways of forming new words,namely,derivation and compounding.They are different in a lot of cases,yet,it is also argued that there is a clear dividing line between compounding and derivation. 展开更多
关键词 AFFIXATION DERIVATION compounding
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Characteristics of super drought in Southwest China and the associated compounding effect of multiscalar anomalies 被引量:2
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作者 Lin WANG Wen CHEN +7 位作者 Gang HAUNG Ting WANG Qiulin WANG Xiaoyun SU Zixuan REN Chakrit CHOTAMONSAK Atsamon LIMSAKUL Kritanai TORSRI 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第7期2084-2102,共19页
In recent decades,Southwest China(SWC)has suffered from frequent super droughts,leading to severe economic losses and ecological degradation.This study investigates the characteristics of super droughts in SWC during ... In recent decades,Southwest China(SWC)has suffered from frequent super droughts,leading to severe economic losses and ecological degradation.This study investigates the characteristics of super droughts in SWC during 1961-2022,reveals the compounding effect of multiscalar anomalies,and explores the plausible atmospheric circulation mechanisms responsible.The nature of super drought is a compound drought caused by the superposition of extreme drought events across multiple time scales.By contrasting the typical drought cases in 2006 and 2022,the decisive role of multiscalar drought compounding is confirmed.Based on the Comprehensive Multiscalar Index(CMI),multiple super drought events in SWC were identified to be temporally clustered during 2006-2014.Among them,the decadal background of enhanced evaporation and precipitation deficit at long time scales is a necessary condition for shaping the overall pattern of super droughts,while the precipitation and evaporation anomalies at short time scales trigger the outbreak of super droughts,determining the exact timing of occurrence.These events include August-September 2006,November 2009 to May 2010,July-October 2011,April-May 2012,January-April 2013,etc.Statistical results suggest that the contribution of superposed precipitation anomalies to super drought is 2.4 times that of evaporation.As regards the circulation mechanisms affecting multiscalar precipitation,the anomalous spatial patterns at short-term and long-term scales are similar,featuring the cyclonic circulation over the South China Sea and the northeasterly wind anomalies together with the subsidence center over SWC.During 2006-2014,the possible causes for the cross-seasonal persistent precipitation reduction in SWC are the extreme negative phase of the Pacific Decadal Oscillation(PDO)in the North Pacific as well as the pronounced warming of the warm pool in the western Pacific.The key dynamic processes are outlined as follows.On the one hand,the negative PDO phase generates anomalous anticyclonic circulation in the North Pacific,with the northeasterly winds on its southwest flank extending to Southeast Asia,hindering moisture transport into SWC.On the other hand,the warming of the warm pool excites anomalous cyclonic circulation to its northwest,also giving rise to northeasterly wind anomalies over SWC.Meanwhile,the ascending motion over the warm pool region diverges at upper levels with outflows converging aloft over SWC,which further induces compensating downward motion there.The combined effect of the above two remote forcings establishes a climatic background state unfavorable for precipitation over SWC at long time scales,thus constituting a crucial prerequisite for the superimposition of short-term precipitation anomalies to develop into super droughts. 展开更多
关键词 Super drought Multiscalar compounding effect Mechanism analysis Southwest China
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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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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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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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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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Ru clusters encapsulated with Al-rich zeolite for efficiently catalytic elimination of 1,2-dichloroethane
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作者 Xiaonan Guo Yuanzhe Yu +5 位作者 Runduo Zhang Shuting Wei Bin Kang Ying Wei Jingbo Jia Zhou-jun Wang 《Journal of Environmental Sciences》 2026年第1期10-22,共13页
The Ru-based catalysts with different preparation methods or supports were achieved and applied in efficientlycatalytic elimination of 1,2-dichloroethane(1,2-DCE).It wasfirstly found that the redox ability and chlorine... The Ru-based catalysts with different preparation methods or supports were achieved and applied in efficientlycatalytic elimination of 1,2-dichloroethane(1,2-DCE).It wasfirstly found that the redox ability and chlorine re-sistance of the catalyst could be improved by regulating the interaction between Ru and supports.Compared withother supports and conventionally impregnated methods,the Ru@ZSM-5 catalyst synthesized by the in-situ en-capsulation strategy exhibited an excellent low-temperature catalytic performance(T50=262°C,T90=327℃),superior stability in long-term test as well as ideal target products.The acidity,specific surface area,and in-teraction with precious metals of the supports have significant influences on the catalytic activity,and the Ruclusters inside the pore structures are more closely bound to the framework Al species,which promotes theoxidation behavior.The encapsulation strategy also significantly improves the Ru dispersion thereby facilitatesoxygen activation as well as Cl-containing volatile organic compounds(CVOCs)deep oxidation,and preserveslarge amounts of Brønsted acid sites to optimize the hydrolysis mechanism for purification of CVOCs.Subse-quently,the synergistic effect between metal redox and acidity is greatly optimized,thus extremely promotingthe catalytic efficiency of 1,2-DCE oxidation. 展开更多
关键词 Catalytic oxidation Encapsulated strategy Volatile organic compounds1 2-dichloroethane Synergistic effect
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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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Preparation of Flame Retardant Containing Phosphorus-nitrogen-boron and Its Application in Polyethylene
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作者 CONG Mengchen LU Shangkai +3 位作者 FANG Jin LIU Junbang AI Lianghui LIU Ping 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期275-284,共10页
MPHPB was prepared from melamine,phenylphosphonic acid and boric acid,and its flame retardant effect in PE was investigated.Compared to the intermediate product(melamine phenyl hypophosphite(MPHP)),the residual char i... MPHPB was prepared from melamine,phenylphosphonic acid and boric acid,and its flame retardant effect in PE was investigated.Compared to the intermediate product(melamine phenyl hypophosphite(MPHP)),the residual char increased from 17.9% of MPHP to 41.2% of MPHPB at 800℃.The limiting oxygen index(LOI)of PE/20%MPHPB is 23.6%,which reaches V-0 rating.After the addition of 20%MPHPB,the total heat release(THR),peak heat release rate(pK-HRR),and average effective thermal combustion rates(av-EHC)of PE decreased.Additionally,characterizations including the pyrolysis gas chromatography-mass spectrometry(Py-GC-MS),scanning electron microscopy(SEM),raman spectroscopy test(LRS)and fourier transform infrared(FT-IR)were taken to investigate the flame retardant mechanism,and the results show that MPHPB plays roles in both gas and condensed phases. 展开更多
关键词 polythene phosphorus-nitrogen-boron compound flame retardant flame retardant mecha‐nism gas and condensed phases flame retardant
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Effects of Morphological Awareness on Reading Comprehension in Beginner Chinese EFL Learners
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作者 Weiqi Huang Rendong Cai Xiaomei Yu 《Chinese Journal of Applied Linguistics》 2025年第4期566-584,639,共20页
This study investigates how English morphological awareness contributes to reading comprehension in beginner Chinese EFL learners.The research examines both derivational and compounding morphological awareness at mult... This study investigates how English morphological awareness contributes to reading comprehension in beginner Chinese EFL learners.The research examines both derivational and compounding morphological awareness at multiple levels(identification,discrimination,and manipulation)on English reading comprehension and explores whether their contributions are mediated by vocabulary knowledge.Data were collected from 71 Grade 9 students using various morphological awareness tasks,a vocabulary test,and a reading comprehension assessment.Mixed-effects regression and mediation analyses revealed that all components of morphological awareness,except derivational identification,significantly contributed to reading comprehension.Derivational manipulation was found to have both direct and indirect effects on reading comprehension,partially mediated by vocabulary knowledge.In contrast,compounding awareness influenced reading comprehension primarily through its effect on vocabulary.These findings provide a more nuanced understanding of how different facets of morphological awareness impact reading comprehension in EFL contexts,offering valuable insights for vocabulary and reading instruction. 展开更多
关键词 morphological awareness derivational morphology compounding morphology L2 reading comprehension
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Preparation and Efficacy Evaluation of a Tibetan Gentiana Face Mask Suitable for Sensitive Skin
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作者 Luo Dan 《Asia Pacific Journal of Clinical Medical Research》 2025年第2期43-49,共7页
This study aims to investigate the antioxidant activity of Tibetan gentian(Gentiana spp.)extract and its essence when compounded with a facial mask matrix.It also evaluates the efficacy of facial masks containing gent... This study aims to investigate the antioxidant activity of Tibetan gentian(Gentiana spp.)extract and its essence when compounded with a facial mask matrix.It also evaluates the efficacy of facial masks containing gentian extract on sensitive facial skin and analyzes the comprehensive performance of the mask.A total of 90 patients with facial sensitive skin,enrolled between October 2022 and December 2024,were randomly assigned to either a control group or an observation group,with 45 patients in each.The control group used standard facial masks,while the observation group used masks containing gentian extract.Both groups underwent a 4-week intervention.The effi cacy,lactic acid stinging test indicators,and skin physiological function parameters were compared between the two groups.Results showed that the overall eff ectiveness rate in the observation group reached 93.26%,signifi cantly higher than 71.20%in the control group(P<0.05).After the intervention,both groups showed notable improvements compared to baseline in lactic acid stinging test scores and physiological skin indicators.Specifi cally,the observation group had signifi cantly lower stinging scores and a longer latency before the onset of stinging compared to the control group.Moreover,the skin pH values were lower,while sebum levels and stratum corneum hydration were higher than those in the control group(P<0.05).No serious adverse events occurred in either group.These fi ndings suggest that facial masks containing gentian extract eff ectively alleviate symptoms of sensitive facial skin,enhance skin barrier function and tolerance,and are safe for use. 展开更多
关键词 Tibetan Gentian Traditional Chinese Medicine Extract Facial Mask Matrix compounding Antioxidant Activity Sensitive Facial Skin
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