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Periodic Crystallization in the Multicomponent Systems
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作者 M.A.Ittyachen Goerge Varghese 《人工晶体学报》 CSCD 1991年第3期337-337,共1页
The periodic precipitation occurs in a gel medium due to counter diffusion of ions,It is shown that the law derived earlier for double component systemcan be modified and found to be true in a multicomponent system.
关键词 multicomponent systems periodic crystallization gel medium counter diffusion double component systemcan periodic precipitation IONS
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Component system regression testing method based on CTAM
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作者 解凯 徐宝文 +2 位作者 聂长海 史亮 章晓芳 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期282-286,共5页
The emphasis of component system regression testing is retesting of the event interaction between updated components and other components in a system.A component system regression testing method based on a new compone... The emphasis of component system regression testing is retesting of the event interaction between updated components and other components in a system.A component system regression testing method based on a new component testing association model (CTAM) is proposed.First,the modification-affected component groups are identified by the impact analysis on CTAM,and each component in this group is assigned with an influence degree.Then,previous test cases are selected according to the influence degree,to generate the minimal regression test suite.Compared with traditional methods,CTAM is derived from the statistic on the interactive events that occurred in previous test executions,and focuses on the complicated relationship between components,which is more applicable to the component system regression testing. 展开更多
关键词 component system testing regression testing test case selection
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Analysis and Research of Design of Assembled Concrete Building Component System Based on BIM
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作者 CUICuimin 《外文科技期刊数据库(文摘版)工程技术》 2022年第7期009-012,共4页
With the improvement of Chinas urban construction level, the scale of the construction industry is constantly expanding, and the traditional production methods, production techniques and production technologies can no... With the improvement of Chinas urban construction level, the scale of the construction industry is constantly expanding, and the traditional production methods, production techniques and production technologies can no longer adapt to the development of cities. With the continuous development and application of building technology, prefabricated building components and BIM technology, the idea of green, low-carbon, environmental protection and sustainable development has become an inevitable choice to promote the transformation and upgrading of the construction industry. Relevant departments of the state, provinces and cities have issued a series of policies, which have promoted the research and development and engineering practice of prefabricated concrete construction technology, and promoted the application of BIM technology in the whole construction process. Therefore, the application of BIM technology in precast concrete structures has become a research hotspot, combining the two will bring greater economic and social benefits. 展开更多
关键词 BIM assembly type concrete building components design method
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Comment on Virtanen et al.(2025) 'Digital components and interaction types in counseling interventions for childhood and adolescent obesity:A systematic review.'
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作者 Alina Yang 《International Journal of Nursing Sciences》 2025年第3期I0001-I0001,共1页
To the Editor:As a student actively involved in advocacy for heart disease prevention,I was particularly intrigued by the policymaking implications of digital interventions in the article "Digital components and ... To the Editor:As a student actively involved in advocacy for heart disease prevention,I was particularly intrigued by the policymaking implications of digital interventions in the article "Digital components and interaction types in counseling interventions for childhood and adolescent obesity:A systematic review" [1].Through my work as the Founder and President of the nonprofit Guardians of Heart,I have developed and promoted early educational programs,digital tools,and community outreach initiatives designed to instill heart-healthy habits in youth,intending to mitigate risk factors such as obesity that significantly contribute to cardiovascular disease later in life. 展开更多
关键词 digital components interaction types adolescent obesity community outreach initiatives heart disease policymaking implications childhood obesity systematic review digital interventions
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Multicolor Circularly Polarized Luminescence of a Single-Component System Revealing Multiple Information Encryption 被引量:6
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作者 Ying Hu Zizhao Huang +1 位作者 Itamar Willner Xiang Ma 《CCS Chemistry》 CSCD 2024年第2期518-527,共10页
Metal-free materials with multicolor tunable circularly polarized luminescence(CPL)are attractive because of their potential applications in information storage and encryption.Here,we designed two enantiomers composed... Metal-free materials with multicolor tunable circularly polarized luminescence(CPL)are attractive because of their potential applications in information storage and encryption.Here,we designed two enantiomers composed of chiral dialkyl glutamides and achiral vibration-induced emission(VIE)moiety,which can switch on CPL after a simple gelation process.It is noteworthy that the CPL colors vary in different solvents,and this is attributed to various self-assembly-induced microstructures,in which the VIE moiety is restrained to different degrees.Accordingly,a multidimensional code system composed of a quick response code,a ultraviolet(UV)light-activated color code,and a CPL information figure was constructed.To our satisfaction,the system possesses multiple information-storage functions.The orthogonal anticounterfeiting and CPLenhanced encryption functions also improve the system information encryption ability.In brief,this study provides a practical example of CPL applied to information security and an effective approach to obtain a single-component color-tunable CPL material with multiple information storage and encryption functions as well. 展开更多
关键词 circularly polarized luminescence information storage and encryption multicolor tunable single component vibration-induced emission
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Association of complement components with risk of colorectal cancer:A systematic review and meta-analysis
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作者 Xiao-Lin Zhu Lu Zhang Su-Xia Qi 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期2168-2180,共13页
BACKGROUND Complement components could contribute to the tumor microenvironment and the systemic immune response.Nevertheless,their role in colorectal cancer(CRC)remains a contentious subject.AIM To elucidate the rela... BACKGROUND Complement components could contribute to the tumor microenvironment and the systemic immune response.Nevertheless,their role in colorectal cancer(CRC)remains a contentious subject.AIM To elucidate the relationship between complement components and CRC risk and clinical characteristics.METHODS Searches were conducted in PubMed,the Cochrane Library,and the China National Knowledge Infrastructure database until June 1,2023.We included cohort studies encompassing participants aged≥18 years,investigating the association between complement components and CRC.The studies were of moderate quality or above,as determined by the Agency for Healthcare Research and Quality.The meta-analysis employed fixed-effects or random-effects models based on the I^(2)test,utilizing risk ratio(RR)and their corresponding 95%confidence interval(CI)for outcomes.Sensitivity and subgroup analyses were performed to validate the robustness of the collective estimates and identify the source of heterogeneity.RESULTS Data from 15 studies,comprising 1631 participants that met the inclusion criteria,were included in the meta-analysis.Our findings indicated that protein levels of cluster of differentiation 46(CD46)(RR=3.66,95%CI:1.75-7.64,P<0.001),CD59(RR=2.86,95%CI:1.36-6.01,P=0.005),and component 1(C1)(RR=5.88,95%CI:1.75-19.73,P=0.004)and serum levels of C3(standardized mean difference=1.82,95%CI:0.06-3.58,P=0.040)were significantly elevated in patients with CRC compared to healthy controls.Strong expression of CD55 or CD59 was associated with a higher incidence of lymph node metastasis,whereas strong CD46 expression correlated with a higher incidence of tumor differentiation compared to low CD46 expression(P<0.05 for all).Although specific pooled results demonstrated notable heterogeneity,subgroup analyses pointed to regional differences as the primary source of inconsistency among the studies.CONCLUSION Our analysis underscores that increased levels of specific complement components are associated with a heightened risk of CRC,emphasizing the potential significance of monitoring elevated complement component levels. 展开更多
关键词 Complement components Colorectal cancer Lymph node metastasis systematic review META-ANALYSIS
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Simultaneous identification of multiple animal-derived components in meat and meat products by using MNP marker based on high-throughput sequencing 被引量:1
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作者 Yan Yi Zhanyue Jiang +9 位作者 Lixia Ma Xiaoni Hou Lun Li Deping Ye Juanlan Du Hai Peng Guoquan Han Huaiping Li Jiangwen Tang Lihua Zhou 《Food Science and Human Wellness》 2025年第4期1566-1575,共10页
In order to save manpower and time costs,and to achieve simultaneous detection of multiple animal-derived components in meat and meat products,this study used multiple nucleotide polymorphism(MNP)marker technology bas... In order to save manpower and time costs,and to achieve simultaneous detection of multiple animal-derived components in meat and meat products,this study used multiple nucleotide polymorphism(MNP)marker technology based on the principle of high-throughput sequencing,and established a multi-locus 10 animalderived components identification method of cattle,goat,sheep,donkey,horse,chicken,duck,goose,pigeon,quail in meat and meat products.The specific loci of each species could be detected and the species could be accurately identified,including 5 loci for cattle and duck,3 loci for sheep,9 loci for chicken and horse,10 loci for goose and pigeon,6 loci for quail and 1 locus for donkey and goat,and an adulteration model was established to simulate commercially available samples.The results showed that the method established in this study had high throughput,good repeatability and accuracy,and was able to identify 10 animalderived components simultaneously with 100%repeatability accuracy.The detection limit was 0.1%(m/m)in simulated samples of chicken,duck and horse.Using the method established in this study to test commercially available samples,4 samples from 14 commercially available samples were detected to be inconsistent with the labels,of which 2 did not contain the target ingredient and 2 were adulterated with small amounts of other ingredients. 展开更多
关键词 Meat and meat products Multiple nucleotide polymorphism marker method High-throughput sequencing Animal-derived component identification
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Research on multi-scale simulation and dynamic verification of high dynamic MEMS components in additive manufacturing 被引量:1
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作者 Sining Lv Hengzhen Feng +2 位作者 Wenzhong Lou Chuan Xiao Shiyi Li 《Defence Technology(防务技术)》 2025年第5期275-291,共17页
Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects s... Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects such as porosity issues, significant deformation, surface cracks, and challenging control of surface morphology encountered during the selective laser melting(SLM) additive manufacturing(AM) process of specialized Micro Electromechanical System(MEMS) components, multiparameter optimization and micro powder melt pool/macro-scale mechanical properties control simulation of specialized components are conducted. The optimal parameters obtained through highprecision preparation and machining of components and static/high dynamic verification are: laser power of 110 W, laser speed of 600 mm/s, laser diameter of 75 μm, and scanning spacing of 50 μm. The density of the subordinate components under this reference can reach 99.15%, the surface hardness can reach 51.9 HRA, the yield strength can reach 550 MPa, the maximum machining error of the components is 4.73%, and the average surface roughness is 0.45 μm. Through dynamic hammering and high dynamic firing verification, SLM components meet the requirements for overload resistance. The results have proven that MEM technology can provide a new means for the processing of MEMS components applied in high dynamic environments. The parameters obtained in the conclusion can provide a design basis for the additive preparation of MEMS components. 展开更多
关键词 Additive manufacturing High dynamic MEMS components Multiscale control Process optimization High dynamic verification
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Prediction of joint roughness coefficient via hybrid machine learning model combined with principal components analysis 被引量:1
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作者 Shijie Xie Hang Lin +2 位作者 Tianxing Ma Kang Peng Zhen Sun 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2291-2306,共16页
Joint roughness coefficient(JRC)is the most commonly used parameter for quantifying surface roughness of rock discontinuities in practice.The system composed of multiple roughness statistical parameters to measure JRC... Joint roughness coefficient(JRC)is the most commonly used parameter for quantifying surface roughness of rock discontinuities in practice.The system composed of multiple roughness statistical parameters to measure JRC is a nonlinear system with a lot of overlapping information.In this paper,a dataset of eight roughness statistical parameters covering 112 digital joints is established.Then,the principal component analysis method is introduced to extract the significant information,which solves the information overlap problem of roughness characterization.Based on the two principal components of extracted features,the white shark optimizer algorithm was introduced to optimize the extreme gradient boosting model,and a new machine learning(ML)prediction model was established.The prediction accuracy of the new model and the other 17 models was measured using statistical metrics.The results show that the prediction result of the new model is more consistent with the real JRC value,with higher recognition accuracy and generalization ability. 展开更多
关键词 Rock discontinuities Joint roughness coefficient(JRC) Roughness characterization Principal components analysis(PCA) Machine learning
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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation
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作者 Xu Liang Ni-Hui Zhang +4 位作者 Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao 《Traditional Medicine Research》 2025年第2期1-15,共15页
Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants h... Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants have some differences in efficacy,but the flower buds are easily confused for similar traits.In addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal roses.Therefore,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography fingerprints.Then,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large differences.Differential compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and Meigui.Results:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the samples.Through principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four groups.Partial least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavonoid glycosides,as well as phenolic acids.Eight differential components were screened out by orthogonal partial least-squares discriminant analysis and S-plot analysis.Quantitative analyses of the eight compounds,including gallic acid,ellagic acid,hyperoside,isoquercitrin,etc.,showed that Yueji was generally richer in phenolic acids and flavonoids than Meigui,and the quality of Yueji from Shandong and Hebei was better.It is worth noting that Xinjiang rose is rich in various components,which is worth focusing on more in-depth research.Conclusion:In this study,the fingerprints of Meigui and Yueji were established.The chemical components information of roses was further improved based on non-targeted metabolomics and mass spectrometry technology.At the same time,eight differential components of Meigui and Yueji were screened out and quantitatively analyzed.The research results provided a scientific basis for the quality control and rational development and utilization of Rosae Chinensis Flos and Rosae Rugosae Flos,and also laid a foundation for the study of their pharmacodynamic material basis. 展开更多
关键词 Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics CHEMOMETRICS multiple component quantification quality evaluation
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The serum fascin-1 and tumor components containing this protein in patients with head and neck squamous cell carcinoma:A pilot study 被引量:1
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作者 Gelena V.Kakurina Elena E.Sereda +4 位作者 Marina N.Stakheeva Liubov Tashireva Olga V.Cheremisina Irina V.Kondakova Evgeny L.Choinzonov 《Journal of Biomedical Research》 2025年第5期534-537,I0046,I0047,共6页
Dear Editor,Local recurrence and cervical lymph node metastases are major causes of mortality in patients with head and neck squamous cell carcinoma(HNSCC).To date,none of the proposed strategies for predicting outcom... Dear Editor,Local recurrence and cervical lymph node metastases are major causes of mortality in patients with head and neck squamous cell carcinoma(HNSCC).To date,none of the proposed strategies for predicting outcomes in this disease have proven fully effective,and a comprehensive physical examination remains the primary method for early detection and monitoring of HNSCC. 展开更多
关键词 serum fascin cervical lymph node metastases tumor components comprehensive physical examination head neck squamous cell carcinoma hnscc head neck squamous cell carcinoma pilot study local recurrence
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Influencing factor of the characterization and restoration of phase aberrations resulting from atmospheric turbulence based on Principal Component Analysis
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作者 WANG Jiang-pu-zhen WANG Zhi-qiang +2 位作者 ZHANG Jing-hui QIAO Chun-hong FAN Cheng-yu 《中国光学(中英文)》 北大核心 2025年第4期899-907,共9页
Restoration of phase aberrations is crucial for addressing atmospheric turbulence in light propagation.Traditional restoration algorithms based on Zernike polynomials(ZPs)often encounter challenges related to high com... Restoration of phase aberrations is crucial for addressing atmospheric turbulence in light propagation.Traditional restoration algorithms based on Zernike polynomials(ZPs)often encounter challenges related to high computational complexity and insufficient capture of high-frequency phase aberration components,so we proposed a Principal-Component-Analysis-based method for representing phase aberrations.This paper discusses the factors influencing the accuracy of restoration,mainly including the sample space size and the sampling interval of D/r_(0),on the basis of characterizing phase aberrations by Principal Components(PCs).The experimental results show that a larger D/r_(0)sampling interval can ensure the generalization ability and robustness of the principal components in the case of a limited amount of original data,which can help to achieve high-precision deployment of the model in practical applications quickly.In the environment with relatively strong turbulence in the test set of D/r_(0)=24,the use of 34 terms of PCs can improve the corrected Strehl ratio(SR)from 0.007 to 0.1585,while the Strehl ratio of the light spot after restoration using 34 terms of ZPs is only 0.0215,demonstrating almost no correction effect.The results indicate that PCs can serve as a better alternative in representing and restoring the characteristics of atmospheric turbulence induced phase aberrations.These findings pave the way to use PCs of phase aberrations with fewer terms than traditional ZPs to achieve data dimensionality reduction,and offer a reference to accelerate and stabilize the model and deep learning based adaptive optics correction. 展开更多
关键词 phase aberration atmospheric turbulence principal component analysis Zernike polynomials
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Therapeutic components of acupuncture stimulation based on characteristics of sensory nerve and nervous signaling pathway
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作者 Hyo-Sun Wie Seung-Nam Kim 《Journal of Integrative Medicine》 2025年第2期106-112,共7页
Acupuncture,a therapeutic practice rooted in traditional Chinese medicine and integrated with modern neuroscience,achieves its effects by stimulating sensory nerves at specific anatomical points known as acupoints.Thi... Acupuncture,a therapeutic practice rooted in traditional Chinese medicine and integrated with modern neuroscience,achieves its effects by stimulating sensory nerves at specific anatomical points known as acupoints.This review systematically explores the therapeutic components of acupuncture,emphasizing the interplay between sensory nerve characteristics and neural signaling pathways.Key factors such as acupoint location,needling depth,stimulation intensity,retention time,and the induction of sensations(e.g.,Deqi)are analyzed for their roles in neural activation and clinical outcomes.The review highlights how variations in spinal segment targeting,tissue-specific receptor activation,and stimulation modalities(e.g.,manual acupuncture,electroacupuncture,moxibustion)influence therapeutic effects.Emerging evidence underscores the significance of ion channels,dermatomes,myotomes,and genespecific pathways in mediating systemic effects.Additionally,the differential roles of mechanical,thermal and nociceptive stimuli and the temporal dynamics of sensory and immune responses are addressed.While insights from animal models have advanced our understanding,their translation to clinical practice requires further investigation.This comprehensive review identifies critical parameters for optimizing acupuncture therapy,advocating for individualized treatment strategies informed by neuroanatomical and neurophysiological principles,ultimately enhancing its precision and efficacy in modern medicine. 展开更多
关键词 Sensory nerve ACUPUNCTURE Nervous system Therapeutic component Acupuncture point MERIDIANS
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Reflections on recent advances in component-based Chinese medicine
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作者 Zi-Bin Lu 《Integrative Medicine Discovery》 2025年第13期1-2,共2页
Component-based Chinese Medicine(CCM)stands as a pivotal endeavor in modernizing traditional Chinese medicine(TCM).By integrating classical TCM theories with modern scientific methodologies,CCM aims to achieve herbal ... Component-based Chinese Medicine(CCM)stands as a pivotal endeavor in modernizing traditional Chinese medicine(TCM).By integrating classical TCM theories with modern scientific methodologies,CCM aims to achieve herbal formulas with“defined components,clarified mechanisms,and controllable quality.”This approach not only transitions TCM development from empirical tradition to evidence-based science but also positions it for global recognition.Drawing on recent advancements in CCM,this editorial explores key insights and challenges shaping its trajectory. 展开更多
关键词 modernizing traditional chinese medicine tcm clarified mechanisms modern scientific methodologiesccm component based Chinese medicine traditional Chinese medicine defined components evidence based science herbal formulas
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Targeted screening and profiling of massive components of colistimethate sodium by two-dimensional-liquid chromatography-mass spectrometry based on self-constructed compound database
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作者 Xuan Li Minwen Huang +11 位作者 Yue-Mei Zhao Wenxin Liu Nan Hu Jie Zhou Zi-Yi Wang Sheng Tang Jian-Bin Pan Hian Kee Lee Yao-zuo Yuan Taijun Hang Hai-Wei Shi Hongyuan Chen 《Journal of Pharmaceutical Analysis》 2025年第2期401-410,共10页
In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics.Similarities and variations of components present significant analytical challenges.A two-dimensional(2... In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics.Similarities and variations of components present significant analytical challenges.A two-dimensional(2D)liquid chromatography-mass spectrometry(LC-MS)method was established for screening and comprehensive profiling of compositions of the antibiotic colistimethate sodium(CMS).A high concentration of phosphate buffer mobile phase was used in the first-dimensional LC system to get the components well separated.For efficient and high-accuracy screening of CMS,a targeted method based on a self-constructed high resolution(HR)mass spectrum database of CMS components was established.The database was built based on the commercial MassHunter Personal Compound Database and Library(PCDL)software and its accuracy of the compound matching result was verified with six known components before being applied to genuine sample screening.On this basis,the unknown peaks in the CMS chromatograms were deduced and assigned.The molecular formula,group composition,and origins of a total of 99 compounds,of which the combined area percentage accounted for more than 95%of CMS components,were deduced by this 2D-LC-MS method combined with the MassHunter PCDL.This profiling method was highly efficient and could distinguish hundreds of components within 3 h,providing reliable results for quality control of this kind of complex drugs. 展开更多
关键词 Colistimethate sodium 2D-LC-MS PROFILING Targeted screening component deduction DATABASE
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Review and Future Perspectives on Lithium Battery Fire Safety:Focusing on Design of Organic Components
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作者 Qianlong Li Yunlei Xu +2 位作者 Ye-Tang Pan Wei Wang Guan Heng Yeoh 《Energy & Environmental Materials》 2025年第4期3-20,共18页
The widespread use of lithium batteries has led to frequent fire hazards,which significantly threaten both human lives and property safety.One of the primary challenges in enhancing the fire safety of lithium batterie... The widespread use of lithium batteries has led to frequent fire hazards,which significantly threaten both human lives and property safety.One of the primary challenges in enhancing the fire safety of lithium batteries lies in the flammability of their organic components.As electronic devices continue to proliferate,the integration of liquid electrolytes and separators has become common.However,these components are prone to high volatility and leakage,which limits their safety.Fortunately,recent advancements in solid-state and gel electrolytes have demonstrated promising performance in laboratory settings,providing solutions to these issues.Typically,improving the flame retardancy and fire safety of lithium batteries involves careful design of the formulations or molecular structures of the organic materials.Moreover,the internal interfacial interactions also play a vital role in ensuring safety.This review examines the innovative design strategies developed over the past 5 years to address the fire safety concerns associated with lithium batteries.Future advancements in the next generation of high-safety lithium batteries should not only focus on optimizing component design but also emphasize rigorous operational testing.This dual approach will drive further progress in battery safety research and development,enhancing the overall reliability of lithium battery systems. 展开更多
关键词 component design fire safety flame retardant lithiumbattery NONFLAMMABLE
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Analysis of Chemical Components of Cocculus laurifolius DC.Based on Liquid Chromatography-Mass Spectrometry
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作者 Lintong HAN Yuzhe LI +5 位作者 Chengxin LAN Bolin BAO Yajie WEI Haicheng WEN Wei WEI Xiaoman ZHONG 《Medicinal Plant》 2025年第1期16-18,共3页
[Objectives]To analyze the main chemical components in Cocculus laurifolius DC.by ultra-high performance liquid chromatography-quaternary rod/electrostatic field orbital hydrazine high resolution mass spectrometry.[Me... [Objectives]To analyze the main chemical components in Cocculus laurifolius DC.by ultra-high performance liquid chromatography-quaternary rod/electrostatic field orbital hydrazine high resolution mass spectrometry.[Methods]Using Welch AQ-C 18 chromatographic column(150 mm×2.1 mm,1.8μm),gradient elution was performed with 0.1%formic acid aqueous solution(A)-methanol(B)as the mobile phase,and electrospray ESI ionization source and simultaneous mass spectrometry scanning mode of positive and negative ions were used.[Results]26 kinds of chemical component were identified or inferred,including 3 organic acids,5 flavonoids,4 alkaloids,1 coumarin and 13 others.[Conclusions]The UPLC-Q-Exactive HRMS technique is simple,which lays a foundation for the drug-efficacy material basis and medicinal quality evaluation of C.laurifolius DC. 展开更多
关键词 Cocculus laurifolius DC. UPLC-Q-Exactive HRMS Chemical component ALKALOIDS FLAVONOIDS
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Refining GNSS-based water storage estimation:Improved hydrological signal extraction using principal component analysis
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作者 Jiaxiang Tian Yulong Zhong +4 位作者 Yingchun Shen Kaijun Yang Hongbing Bai Fan Lei Changqing Wang 《Geodesy and Geodynamics》 2025年第5期591-603,共13页
The Global Navigation Satellite System(GNSS)is vital for monitoring terrestrial water storage(TWS).However,effectively extracting hydrological load deformation from GNSS observations poses a significant challenge.This... The Global Navigation Satellite System(GNSS)is vital for monitoring terrestrial water storage(TWS).However,effectively extracting hydrological load deformation from GNSS observations poses a significant challenge.This study proposes a novel strategy;the seasonal hydrological load signals are removed from the raw data,and the remaining signals use principal component analysis(PCA).Simulation results from Yunnan Province demonstrate that the spatial distribution of the root mean square error(RMSE)is improved by approximately 15% compared with traditional PCA extraction from raw data.From January 2013 to December 2022,TWS was inverted from 24 GNSS stations in Yunnan Province.The spatial distribution and time series of TWS inverted from GNSS align well with those TWS inferred from the Gravity Recovery and Climate Experiment(GRACE),GRACE Follow-On(GFO),and the Global Land Data Assimilation System(GLDAS)land surface model.However,the amplitude of the GNSS-inverted TWS is slightly higher.Since GNSS ground stations are more sensitive to hydrological load signals,they show correlations with precipitation data that are 8.6%and 6.0%higher than those of GRACE and GLDAS,respectively.In the power spectral density analysis of GRACE/GFO,GLDAS,and GNSS,the signal strength of GNSS is much higher than that of GRACE/GFO and GLDAS in the June and February cycles.These findings suggest that the new data extraction strategy can capture higher frequency hydrological signals in TWS,and GNSS observations can help address limitations in GRACE/GFO observations.This study demonstrates the potential of GNSS TWS in capturing higher-frequency hydrological signals and climate extremes application. 展开更多
关键词 Hydrography GNSS Green's function Principal component analysis Yunnan Province
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Microstructure and mechanical properties of ZK61 magnesium alloy thin-walled cylindrical component processed by two-step forging
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作者 Fang Chai Jianqiang Feng +6 位作者 Xinghui Han Wuhao Zhuang Yizhe Chen Zhili Hu Xuan Hu Fangyan Zheng Lin Hua 《Journal of Magnesium and Alloys》 2025年第5期2416-2432,共17页
Magnesium alloy thin-walled cylindrical components with the advantages of high specific stiffness and strength present broad prospect for the lightweight of aerospace components.However,poor formability resulting from... Magnesium alloy thin-walled cylindrical components with the advantages of high specific stiffness and strength present broad prospect for the lightweight of aerospace components.However,poor formability resulting from the hexagonal close-packed crystal structure in magnesium alloy puts forwards a great challenge for thin-walled cylindrical components fabrication,especially for extreme structure with the thicknesschanging web and the high thin-wall.In this research,an ZK61 magnesium alloy thin-walled cylindrical component was successfully fabricated by two-step forging,i.e.,the pre-forging and final-forging is mainly used for wed and thin-wall formation,respectively.Microstructure and mechanical properties at the core,middle and margin of the web and the thin-wall of the pre-forged and final-forged components are studied in detail.Due to the large strain-effectiveness and metal flow along the radial direction(RD),the grains of the web are all elongated along RD for the pre-forged component,where an increasingly elongated trend is found from the core to the margin of the wed.A relatively low recrystallized degree occurs during pre-forging,and the web at different positions are all with prismatic and pyramid textures.During finalforging,the microstructures of the web and the thin-wall are almost equiaxed due to the remarkable occurrence of dynamic recrystallization.Similarity,except for few basal texture of the thin-wall,only prismatic and pyramid textures are found for the final-forged component.Compared with the initial billet,an obviously improved mechanical isotropy is achieved during pre-forging,which is well-maintained during final-forging. 展开更多
关键词 Magnesium alloy Thin-walled cylindrical component Two-step forging Microstructure Mechanical properties
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Diversified rotation systems improve grain yield and water use efficiency of winter wheat under limited irrigation in the North China Plain
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作者 Lei Yang Lang Cheng +5 位作者 Pin Wang Huiling Zhao Jie Zhao Huadong Zang Yadong Yang Zhaohai Zeng 《The Crop Journal》 2025年第4期1271-1280,共10页
Diversifying crop rotation aims to balance production and ecological concerns.However,yield and water use efficiency(WUE)of crop in diversified rotation systems have not been well documented,especially under limited i... Diversifying crop rotation aims to balance production and ecological concerns.However,yield and water use efficiency(WUE)of crop in diversified rotation systems have not been well documented,especially under limited irrigation.Here,we conducted a 6-year experiment with five treatments:1)wheatmaize cropping system(WM),as control;2)WMME,spring maize→WM rotation;3)WMML,spring millet→WM rotation;4)WMMP,spring peanut→WM rotation;and 5)WMMS,spring soybean→WM rotation,to explore how diversified rotations affected yield and WUE of wheat.Results showed that approximately 60% higher precipitation during wheat growing season in Cycle 1(2015-2017)resulted in yield increases by 33.8%-55.7% compared to those in Cycle 2(2017-2019)and Cycle3(2019-2021).Grain yield and WUE of wheat were 16.7% and 9.6% higher in Cycle 1,81.5% and 86.8% higher in Cycle 2,and 56.1% and 78.7% higher in Cycle 3 on average in diversified rotations compared to those in WM,respectively.Further analysis revealed that spike number and aboveground biomass were the main contributors to the increments,which can be explained by the increased evapotranspiration during the middle-late wheat growth stages(e.g.,regreening,jointing,and anthesis)in diversified rotations.In general,diversified rotations enhanced synchronization of soil water supply with crop water demand by affecting the spatiotemporal dynamics of soil moisture under varied precipitation conditions,thereby increasing yield and WUE of wheat.Hence,diversified spring crops→WM rotations offer a sustainable and efficient strategy for enhancing wheat production and water conservation in dry areas. 展开更多
关键词 Rotation system Yield component Soil water storage EVAPOTRANSPIRATION
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