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Mathematical Modeling and a Multiswarm Collaborative Optimization Algorithm for Fuzzy Integrated Process Planning and Scheduling Problem

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Tsinghua Science and Technology 2024年第2期29卷 285-304页

作者： Qihao liu Cuiyu Wang Xinyu li liang Gao State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

Considering both process planning and shop scheduling in manufacturing can fully utilize their complementarities,resulting in improved rationality of process routes and high-quality and efficient production. Hence,the study of Integrated Process Planning and Scheduling (IPPS) has become a hot topic in the current production field. However,when performing this integrated optimization,the uncertainty of processing time is a realistic key point that cannot be neglected. Thus,this paper investigates a Fuzzy IPPS (FIPPS) problem to minimize the maximum fuzzy completion time. Compared with the conventional IPPS problem,FIPPS considers the fuzzy process time in the uncertain production environment,which is more practical and realistic. However,it is difficult to solve the FIPPS problem due to the complicated fuzzy calculating rules. To solve this problem,this paper formulates a novel fuzzy mathematical model based on the process network graph and proposes a MultiSwarm Collaborative Optimization Algorithm (MSCOA) with an integrated encoding method to improve the optimization. Different swarms evolve in various directions and collaborate in a certain number of iterations. Moreover,the critical path searching method is introduced according to the triangular fuzzy number,allowing for the calculation of rules to enhance the local searching ability of MSCOA. The numerical experiments extended from the well-known Kim benchmark are conducted to test the performance of the proposed MSCOA. Compared with other competitive algorithms,the results obtained by MSCOA show significant advantages,thus proving its effectiveness in solving the FIPPS problem.

关键词： Integrated Process Planning and Scheduling(IPPS) fuzzy processing time fuzzy completion time MultiSwarm Collaborative Optimization Algorithm(MSCOA)

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High-Performanceα-Diimine Nickel Complexes for Facile Access of PE Elastomers with Exceptional Material Properties

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Chinese Journal of Polymer Science 2024年第5期42卷 620-635,I0008页

作者： li-Dong Qin Xin-Yu Wang Qaiser Mahmood Zhi-Xin Yu Yi-Zhou Wang Song Zou Tong-ling liang wen-Hua Sun School of Pharmaceutical Sciences Changchun University of Chinese MedicineChangchun130117China Chemistry and Chemical Engineering Guangdong Laboratory Shantou515031China Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China

For practicable elastomeric polyethylene,achieving high catalyst thermal stability and activity,along with precise control of polymer properties such as branching density,molecular weights,and distribution,is crucial but *** this study,two sets of symmetricalα-diimine nickel complexes,each comprising four nickel bromide or chloride complexes,were synthesized and investigated their performance for ethylene polymerization under various reaction *** activation with either Et2AlCl or MMAO cocatalysts,these complexes displayed not only high activity but also generated high molecular weight polyethylenes with controlled polydispersity and a substantial number of *** catalyst with the least steric hindrance displayed the remarkable high activity(up to 1.2×10^(7) g·mol^(-1)·h^(-1)).Notably,nickel bromides demonstrated higher activity compared to their chloride *** investigation into the effect of reaction temperature on catalytic performance revealed that NiBrMe-MMAO system displayed high thermal stability(activity up to 2.51×10^(6) g·mol^(-1)·h^(-1) at 100℃)and consistently yielded high polymer molecular weights with narrow polydispersity over a broad temperature range of 30-100℃.Of significant note,mechanical analysis of the resulting polyethylene demonstrated excellent ultimate tensile strength and high strain at ***,the polyethylene sample prepared at 100℃exhibited ultimate tensile strength up to 10 MPa with 1863%maximum strain at break and a strain recovery of up to 54.9%after ten cycles at a fixed strain of 300%,indicating excellent material properties of prepared thermoplastic polyethylene elastomers(TPE).

关键词： Thermoplastic polyethylene elastomers α-Diimine nickel pre-catalysts Ethylene polymerization Mechanical properties Highly branched polyethylene

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Uniqueness on Difference Operators of Meromorphic Functions of Infinite Order

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Acta Mathematica Sinica,English Series 2024年第2期40卷 511-527页

作者： Hui li Ming liang FANG Xiao YAO School of Science China University of Mining and TechnologyBeijing 100083P.R.China Institute of Mathematics Academy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100190P.R.China School of Sciences Hangzhou Dianzi UniversityHangzhou 310012P.R.China School of Mathematical sciences and LPMC Nankai UniversityTianjin 300071P.R.China

We investigate the uniqueness problems of meromorphic functions and their difference operators by using a new *** is proved that if a non-constant meromorphic function f shares a non-zero constant and ∞ counting multiplicities with its difference operators Δcf(z) and Δ_(c)^(2)f(z), thenΔcf(z)≡Δ_(c)^(2)f(z).In particular,we give a difference analogue of a result of *** method has two distinct features:(ⅰ) It converts the relations between functions into the corresponding *** makes it possible to deal with the uniqueness problem by linear algebra and combinatorics.(ⅱ) It circumvents the obstacle of the difference logarithmic derivative lemma for meromorphic functions of infinite order,since this method does not depend on the growth of the ***,the idea in this paper can also be applied to the case for several variables.

关键词： Uniqueness meromorphic functions difference operators infinite order

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Signifying quantum uncertainty relations by optimal observable sets and the tightest uncertainty constants

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Science China(Physics,Mechanics & Astronomy) 2024年第9期Mechanics & Astronomy) .卷 47-54页

作者： Xiao-Bin liang Bo li Shao-Ming Fei School of Mathematics and Computer Science Shangrao Normal University Quantum Information Research Center Shangrao Normal University School of Mathematical Sciences Capital Normal University

Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical observables. Here, we introduce the concept of optimal observable sets and define the tightest uncertainty constants to accurately describe these measurement uncertainties. For any quantum state, we establish optimal sets of three observables for both product and summation forms of uncertainty relations, and analytically derive the corresponding tightest uncertainty constants. We demonstrate that the optimality of these sets remains consistent regardless of the uncertainty relation form. Furthermore, the existence of the tightest constants excludes the validity of standard real quantum mechanics, underscoring the essential role of complex numbers in this field. Additionally, our findings resolve the conjecture posed in [Phys. Rev. Lett. 118, 180402(2017)],offering novel insights and potential applications in understanding preparation uncertainties.

关键词： uncertainty relation the tightest uncertainty constants optimal observable sets

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Hole cleaning evaluation and installation spacing optimization of cuttings bed remover in extended-reach drilling

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Petroleum Science 2024年第3期21卷 2005-2022页

作者： Shuo Peng wen-Jun Huang De-li Gao MOE Key Laboratory of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBeijing102249China

In extended-reach or long-horizontal drilling,cuttings usually deposit at the bottom of the *** cuttings accumulate to a certain thickness,complex problems such as excessive torque and drag,tubing buckling,and pipe stuck probably occur,which results in a lot of non-productive time and remedial *** bed remover can efficiently destroy deposited cuttings in time through hydraulic and mechanical stirring *** paper aims to build a method for hole cleaning evaluation and installation spacing optimization of cuttings bed remover to improve the wellbore cleaning ***,a Computational Fluid Dynamics approach with Eulerian—Eulerian multiphase model was utilized to investigate the mechanism of cuttings transportation,and a new type of cuttings bed remover was ***,an evaluation method of hole cleaning effect of remover was *** that,the effects of several drilling parameters on hole cleaning including flow rate of drilling fluid,rotational speed of drillpipe,rate of penetration,wellbore size,rheological property of drilling fluid,and remover eccentricity on the performance of cuttings bed remover were *** results demonstrate that the new type of remover with streamline blade performs better than conventional *** efficiency of hole cleaning is greatly improved by increasing the rotational speed of drillpipe,flow rate of drilling fluid,remover eccentricity,and 6 rpm Fann dial reading for drilling *** higher rate of penetration and large wellbore size result in worse hole *** findings can serve as an important guide for the structure optimization design of cuttings bed remover and installation spacing of removers.

关键词： Extended-reach drlling Drilling hydraulics Cuttings transport Hole cleaning Cuttings bed remover

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Spatially Coupled Codes via Bidirectional Block Markov Superposition Transmission

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Tsinghua Science and Technology 2024年第3期29卷 656-670页

作者： Gaoyan li Shancheng Zhao Haiqiang Chen Jinming wen College of Information Science and Technology Jinan UniversityGuangzhou 510632China Guangxi Key Laboratory of Multimedia Communications and Network Technology Guangxi UniversityNanning 530004China

In this paper,we present a new class of spatially coupled codes obtained by using both non-recursive and recursive block-oriented *** resulting codes are termed as bidirectional block Markov superposition transmission(BiBMST)***,we perform an iterative decoding threshold analysis according to protograph-based extrinsic information transfer(PEXIT)charts for the BiBMST codes over the binary erasure channels(BECs).Secondly,we derive the generator and parity-check matrices of the BiBMST ***,extensive numerical results are presented to show the advantages of the proposed BiBMST ***,our numerical results show that,under the constraint of an equal decoding latency,the BiBMST codes perform better than the recursive BMST(rBMST)***,the simulation results show that,in finite-length regime,negligible performance gain is obtained by increasing the encoding *** solve this limitation by introducing partial superposition,and the resulting codes are termed as partially-connected BiBMST(PC-BiBMST)*** results have confirmed the advantages of the PC-BiBMST codes over the original BiBMST *** also present extensive simulation results to show the performance advantages of the PC-BiBMST codes over the spatially coupled low-density parity-check(SC-LDPC)codes,spatially coupled generalized LDPC(SC-GLDPC)codes,and the original BiBMST codes in the finite-length regime.

关键词： block Markov superposition transmission(BMST) protograph-based extrinsic information transfer(PEXIT) capacity-approaching codes spatial coupling

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An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： Qi liu Xue-Dong li liang Cheng li liu Beijing National Laboratory for Molecular Sciences (BNLMS) CAS Key Laboratory of Molecular Recognition and Function CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements, which provides efficient methods for the preparation of axially chiral compounds. However, developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination process. In this work, we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent enantioselectivity. In addition, the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis acid. This methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%) and excellent central-to-axial chirality conversion(up to 99% conversion percentage). This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： brønsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

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Cascade electrolysis and thermocatalysis: a reliable system for upgrading C1 to C4 hydrocarbons

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Rare Metals 2024年第1期43卷 410-412页

作者： Chao-Yue Sun wen li Hai-Qing Wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China

The carbon cycle is important for maintaining a stable climate and carbon balance on Earth. Renewable-electricitydriven upcycling of carbon dioxide (CO_(2)) into value-added multi-carbon molecules is a potentially sus... 详细信息

关键词： cycling hydrocarbons enable

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Research status and hotspots of tight junctions and colorectal cancer:A bibliometric and visualization analysis

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3705-3715页

作者： Hui-Min li Yin liu Meng-Di Hao Xiao-Qing liang Da-Jin Yuan wen-Bin Huang wen-Jie li Lei Ding Department of Gastrointestinal Oncology Surgery Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China

BACKGROUND Colorectal cancer(CRC)is the third most common cancer worldwide and the second leading cause of cancer-related *** the past two decades,numerous researchers have provided important evidence regarding the role of tight junction(TJ)proteins in the occurrence and progression of *** causal relationship between the presence of specific TJ proteins and the development of CRC has also been *** the large number of publications in this field,a bibliometric study to review the current state of research and highlight the research trends and hotspots in this field has not yet been *** To analyze research on TJs and CRC,summarize the field’s history and current status,and predict future research *** We searched the Science Citation Index Expanded database for all literature on CRC and TJs from *** used bibliometrics to analyze the data of these papers,such as the authors,countries,institutions,and ***-authorship,co-citation,and co-occurrence analyses were the main methods of *** and VOSviewer were used to visualize the *** A total of 205 studies were ultimately *** number of publications on this topic has steadily increased since *** and the United States have made the largest contributions to this *** Research was the most prolific journal,publishing 8 articles,while the journal Oncogene had the highest average citation rate(68.33).Professor Dhawan P was the most prolific and cited author in this ***-occurrence analysis of keywords revealed that“tight junction protein expression”,“colorectal cancer”,“intestinal microbiota”,and“inflammatory bowel disease”had the highest frequency of occurrence,revealing the research hotspots and trends in this *** This bibliometric analysis evaluated the scope and trends of TJ proteins in CRC,providing valuable research perspectives and future directions for studying the connection between th

关键词： Colorectal cancer Tight junctions Bibliometric analysis Research trends Hot spots

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Two Indium(III)-based Fluorescent Metal-Organic Frameworks for Highly Sensing Fe^(3+),2,4-DNP,and TNP

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Chemical Research in Chinese Universities 2024年第1期40卷 119-126页

作者： WANG Dan li wen li Guanghua HUA Jia liU Yunling State Key Laboratory of Inorganic Synthesis&Preparative Chemistry Jilin UniversityChangchun130012P.R.China

Two novel metal-organic frameworks(MOFs),JLU-MOF130([In(NH2−BDC)(Imi)(1H−Imi)]·DMF·H2O,NH2−H2BDC=2-aminobenzene-1,4-dicarboxylic acid,1H−Imi=1H-imidazole,DMF=N,N-dimethylformamide)and JLU-MOF131([In(1,4-NDC)(Imi)(1H−Imi)]·DMF0.5,1,4-H_(2)NDC=1,4-naphthalene-dicarboxylic acid),were ***-MOF130 features a three-dimensional(3D)architecture with a neb ***-MOF131 is characterized by a two-dimensional(2D)structure with an sql ***-MOF130 has excellent fluorescence detection performance towards Fe^(3+),2,4-dinitrophenol(2,4-DNP),and 2,4,6-trinitrophenol(TNP),but the fluorescence detection performance of JLU-MOF131 is further improved by converting NH2−H2BDC to more conjugated 1,4-H_(2)*** Stern-Volmer(SV)quenching constant(KSV)values of JLU-MOF130 sensing 2,4-DNP,TNP,and Fe^(3+)are 5.24×10^(4),4.44×10^(4),and 4.73×10^(3) L/mol,*** corresponding limit of detection(LOD)values are 1.17,1.36,and 14.59µmol/*** KSV values for JLU-MOF131 are 1.26×10^(5),9.02×10^(4),and 8.48×103 L/mol,and the corresponding LOD values are 0.35,0.42,and 3.60µmol/L,***,the emission wavelengths of the two MOFs obviously shift as the fluorescence emission intensities decrease upon the addition of 2,4-DNP and TNP,which can be applied in selective detection.

关键词： Metal-organic framework Fluorescence quenching Fe^(3+) 2 4-Dinitrophenol(2 4-DNP) 2 4 6-Trinitrophenol(TNP)

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