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Flow Injection Analysis Technique for Online Preconcentration of Lead Ions in Airborne Particulate Matter Using Imprinted Polymer as the Sorbent

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Journal of Analysis and Testing 2024年第2期8卷 180-190页

作者： Muhammad Bachri Amran Novita Ambarsari Muhammad Ali Zulfikar Asri Indrawati Rusnadi Rusnadi Saipul Hamdi Analytical Chemistry Division Faculty of Mathematics and Natural SciencesInstitut Teknologi

This work reported a simple and sensitive flow injection analysis(FIA)technique coupled with a Flame Atomic Absorption Spectrophotometer(FAAS)for online preconcentration of lead(Ⅱ)ions in the airborne particulate matter samples(PM_(2.5))using ion-imprinted polymers as adsorbent packed in minicolumn.A bulk polymerization method was chosen to synthesize the polymer based on a ternary complex of lead ions with 4-2-pyridilazo resorcinol and 4-vinyl pyridine with methacrylic acid as a functional monomer.The optimum pH for sorption was 6,and other variables for the FIA system were optimized,including breakthrough volume,eluent concentration,and eluent volume.The optimum conditions were reached with a breakthrough volume of 4.45 mL,calculated as a dynamic retention capacity of 5.20 mg/g of Pb(II)40 mg/L,with a 1.5 mL/min flow rate.The eluent used for the FIA system was 0.5 mL HNO_(3)of 3 mol/L.Linearity,precision,and limits of detection of the FIA system were determined before being applied to preconcentration and analysis of lead ions in PM_(2.5)samples.The precision of the method was determined to be 3.09%by calculating the coefficients of the variant.Linearity of the method in the concentration range of 50-1000μg/L gave a coefficient correlation of 0.9925,showing a good response,and the limit of detection of the system was 5.11μg/L,better than that of the FAAS method.Performances of the FIA system were evaluated and showed good results with an enrichment factor of more than 20 times higher and a concentration efficiency of 11.65 min^(-1)with a consumptive index of 4.5 mL.Preconcentration and analysis of the PM_(2.5)samples in Bandung City showed the concentrations of Pb(II)were 26.67μg/L and 33.3μg/L with the accuracy of the method for each sample of104.75%and 107.86%.

关键词： Flow injection analysis Lead(II)ions Imprinted polymer Particulate matter

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A generalization of Banach's lemma and its applications to perturbations of bounded linear operators

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Applied mathematics(A Journal of Chinese Universities) 2024年第2期39卷 363-369页

作者： WANG Zi DING Jiu WANG Yu-wen School of mathematics sciences Harbin Normal UniversityHarbin 150025China School of mathematics and natural sciences The University of Southern MississippiHattiesburg MS 39406-5043USA Academic Committee Harbin Institute of PetroleumHarbin 150027China

Let X be a Banach space and let P:X→X be a bounded linear operator.Using an algebraic inequality on the spectrum of P,we give a new sufficient condition that guarantees the existence of(I-P)^(-1) as a bounded linear operator on X,and a bound on its spectral radius is also obtained.This generalizes the classic Banach lemma.We apply the result to the perturbation analysis of general bounded linear operators on X with commutative perturbations.

关键词： Banach lemma spectral radius generalized inverse perturbation analysis

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2-local unstable homotopy groups of indecomposable A32-complexes

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Science China mathematics 2024年第3期67卷 607-626页

作者： Zhongjian Zhu Jianzhong Pan College of mathematics and Physics Wenzhou University Hua Loo-Keng Key Laboratory of mathematics Institute of MathematicsAcademy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical sciences University of Chinese Academy of Sciences

In this paper,we calculate the 2-local unstable homotopy groups of indecomposable A32-complexes.The main technique used is analysing the homotopy property of J(A,X),defined by Gray(1973) for a CW-pair(X,A),which is ho... 详细信息

关键词： homotopy groups A 2 n -complexes fibration sequence relative James construction 55P15

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Dieback of managed spruce stands in western Germany promotes beetle diversity

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Journal of Forestry Research 2024年第3期35卷 55-71页

作者： Eva Plath Chantal Trauth Jan Gerhards Laura Griebel Klaus Fischer Department Biology Institute of Integrated Natural SciencesKoblenz-Landau University56070 KoblenzGermany

Biodiversity loss is a significant problem at a global scale and may be amplified by climate change.In recent years,coniferous forests have had substantial die-back across Europe due to drought and subsequent bark-beetle outbreaks.As many studies on the consequences of disturbance and subsequent management have focused on natural stands,management implications for managed spruce stands are not well understood,even though such stands are widespread throughout Europe.In this study,beetle taxonomy,conservation value,and community com-position are compared among spruce plantations and four post-disturbance management approaches:standing dead-wood,lying deadwood,clear cuts,and long-term succession.Diversity and community composition differed significantly among management categories,while different beetle fami-lies responded similarly.Intact spruce stands harbored the lowest beetle diversity while the highest taxonomic diver-sity and conservation value was on clear cuts and stands with lying or standing deadwood.The proportion of forest specialists was highest in successional forests.In summary,different forest management categories harbored distinct beetle communities at the family-,species-,and ecological guild levels.Therefore,post-disturbance management should consider the landscape scale and include different management types.This enhances landscape heterogeneity and thus overall biodiversity but could also mitigate negative impacts of natural disturbances on ecosystem services.

关键词： Bark-beetle outbreak Forest dieback Spruce Deadwood Nature conservation Beetle biodiversity-Coleoptera Coniferous forests

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H?lder continuous weak solutions of the 2D Boussinesq equation with thermal diffusion

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Science China mathematics 2024年第8期67卷 1777-1806页

作者： Tianwen Luo Tao Tao Liqun Zhang Yau Mathematical sciences Center Tsinghua University School of mathematics Shandong University institute of mathematics Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical sciences University of Chinese Academy of Sciences

We show the existence of H?lder continuous periodic weak solutions of the 2D Boussinesq equation with thermal diffusion which satisfy the prescribed kinetic energy. More precisely, for any smooth e(t):[0, 1]→■ and ... 详细信息

关键词： 2D Boussinesq equation with thermal diffusion Hölder continuous periodic weak solutions prescribed kinetic energy

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Consequences of Rényi entropy on the thermal geometries and Hawking evaporation of topological dyonic dilaton black hole

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Communications in Theoretical Physics 2024年第2期76卷 102-110页

作者： Muhammad Yasir Xia Tiecheng Muhammad Usman Shahid Chaudhary Department of mathematics Shanghai University and Newtouch Center for Mathematics of Shanghai UniversityShanghai200444China Department of natural sciences and Humanities University of Engineering and Technology LahoreNew CampusPakistan

The thermodynamics of black holes(BHs)has had a profound impact on theoretical physics,providing insight into the nature of gravity,the quantum structure of spacetime and the fundamental laws governing the Universe.In this study,we investigate thermal geometries and Hawking evaporation of the recently proposed topological dyonic dilaton BH in anti-de Sitter(Ad S)space.We consider Rényi entropy and obtain the relations for pressure,heat capacity and Gibbs free energy and observe that the Rényi parameter and dilaton field play a vital role in the phase transition and stability of the BH.Moreover,we use Weinhold,Ruppeiner and Hendi Panahiyah Eslam Momennia models to evaluate the scalar curvature of the BH and find out that the divergence points of the scalar curvature coincides with the zero of specific heat.Finally,using Stefan–Boltzmann law,we determine that the BH without a dilaton field evaporates far more quickly compared to the dilaton BH in Ad S space.

关键词： topological dyonic dilaton black hole phase transition thermal geometry Hawking evaporation

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A comprehensive review on pharmacognosy, phytochemistry and pharmacological activities of 8 potent Prunus species of southeast Asia

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Journal of Traditional Chinese Medicine 2024年第3期44卷 620-628页

作者： Shikha Agrawal Adarsh Kumar Ankit Kumar Singh Harshwardhan Singh Suresh Thareja Pradeep Kumar Department of Pharmaceutical sciences and natural Products Central University of Punjab

Genus Prunus comprising around 430 species is a vast important genus of family Rosaceae, subfamily amygdalaoidae. Among all 430 species, around 19 important species are commonly found in Indian subcontinent due to their broad nutritional and economic importance. Some most common species of genus Prunus are Prunus amygdalus, Prunus persica, Prunus armeniaca, Prunus avium, Prunus cerasus, Prunus cerasoides, Prunus domestica, Prunus mahaleb, etc. A newly introduced species of Prunus i.e Prunus sunhangii is recently discovered which is morphologically very similar to Prunus cerasoides. Plants of Prunus species are short to medium-sized deciduous trees mainly found in the northern hemisphere. In India and its subcontinent,it extends from the Himalayas to Sikkim, Meghalaya,Bhutan, Myanmar etc. Different Prunus species have been extensively studied for their morphological,microscopic, pharmacological and phytoconstituents characteristics. Total phenolic content of Prunus species explains the presence of phenols in high quantity and pharmacological activity due to phenols. Phytochemical screening of species of genus Prunus shows the presence of wide phytoconstituents which contributes in their pharmacological significance and reveals the therapeutic potential and traditional medicinal significance of this genus. Genus Prunus showed a potent antioxidant activity analyzed by 1,1-diphenyl-2-picryl-hydrazyl radical assay. Plant species belonging to the genus Prunus is widely used traditionally for the treatment of various disorders. Some specific Prunus species possess potent anticancer, anti-inflammatory,hypoglycemic etc. activity which makes the genus more interesting for further research and findings. This review is an attempt to summarize the comprehensive study of Prunus species from its distribution, morphological characters to phytoconstituents, and pharmacological activity.

关键词： Prunus Rosaceae antineoplastic agents distribution hypoglycemic agents phytochemistry review

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Tocotrienol isoforms:The molecular mechanisms underlying their effects in cancer therapy and their implementation in clinical trials

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Journal of Integrative Medicine 2024年第1期22卷 1-11页

作者： Maria Younes Ghady Loubnane Christopher Sleiman Sandra Rizk Department of natural sciences Lebanese American UniversityByblosLebanon

Tocotrienols are found in a variety of natural sources,like rice bran,annatto seeds and palm oil,and have been shown to have several health-promoting properties,particularly against chronic diseases such as cancer.The incidence of cancer is rapidly increasing around the world,not only a result of continued aging and population growth,but also due to the adoption of aspects of the Western lifestyle,such as high-fat diets and low-physical activity.The literature provides strong evidence that tocotrienols are able to inhibit the growth of various cancers,including breast,lung,ovarian,prostate,liver,brain,colon,myeloma and pancreatic cancers.These findings,along with the reported safety profile of tocotrienols in healthy human volunteers,encourage further research into these compounds’potential use in cancer prevention and treatment.The current review provided detailed information about the molecular mechanisms of action of different tocotrienol isoforms in various cancer models and evaluated the potential therapeutic effects of different vitamin E analogues on important cancer hallmarks,such as cellular proliferation,apoptosis,angiogenesis and metastasis.MEDLINE/PubMed and Scopus databases were used to identify recently published articles that investigated the anticancer effects of vitamin E derivatives in various types of cancer in vitro and in vivo along with clinical evidence of adjuvant chemopreventive benefits.Following an overview of pre-clinical studies,we describe several completed and ongoing clinical trials that are paving the way for the successful implementation of tocotrienols in cancer chemotherapy.

关键词： Vitamin E Tocotrienols Cancer Molecular mechanism Clinical trials

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A Deep Learning Method for Computing Eigenvalues of the Fractional Schrödinger Operator

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Journal of Systems Science & Complexity 2024年第2期37卷 391-412页

作者： GUO Yixiao MING Pingbing LSEC Institute of Computational Mathematics and Scientific/Engineering ComputingAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical sciences University of Chinese Academy of SciencesBeijing 100049China

The authors present a novel deep learning method for computing eigenvalues of the fractional Schrödinger operator.The proposed approach combines a newly developed loss function with an innovative neural network architecture that incorporates prior knowledge of the problem.These improvements enable the proposed method to handle both high-dimensional problems and problems posed on irregular bounded domains.The authors successfully compute up to the first 30 eigenvalues for various fractional Schrödinger operators.As an application,the authors share a conjecture to the fractional order isospectral problem that has not yet been studied.

关键词： Eigenvalue problem deep learning fractional Schrödinger operator isospectral problem

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Stability of the Phase Separation State for Compressible Navier-Stokes/Allen-Cahn System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 45-74页

作者： Ya-zhou Chen Hakho Hong Xiao-ding Shi Department of mathematics College of Mathematics and PhysicsBeijing University of Chemical TechnologyBeijing100029China institute of mathematics State Academy of SciencesPyongyangKorea

This paper is concerned with the large time behavior of the Cauchy problem for Navier-Stokes/AllenCahn system describing the interface motion of immiscible two-phase flow in 3-D. The existence and uniqueness of global solutions and the stability of the phase separation state are proved under the small initial perturbations. Moreover, the optimal time decay rates are obtained for higher-order spatial derivatives of density,velocity and phase. Our results imply that if the immiscible two-phase flow is initially located near the phase separation state, then under small perturbation conditions, the solution exists globally and decays algebraically to the complete separation state of the two-phase flow, that is, there will be no interface fracture, vacuum, shock wave, mass concentration at any time, and the interface thickness tends to zero as the time t → +∞.

关键词： Navier-Stokes/Allen-Cahn system existence uniqueness large time behavior decay rate

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