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ENVIRONMENTAL ISSUES IN THE AgRO BASED INDIAN PULP & PAPER INDUSTRY

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天津科技大学学报 2004年第S2期 168-173页

作者： S. Panwar,N.Endlay,S.Mishra,R.M.Mathur,a.g.kulkarni ScientistsCentral Pulp & Paper Research InstituteSaharanpur -247001 (U.P.) India ScientistsCentral Pulp & Paper Research InstituteSaharanpur -247001 (U.P.) India ScientistsCentral Pulp & Paper Research InstituteSaharanpur -247001 (U.P.) India ScientistsCentral Pulp & Paper Research InstituteSaharanpur -247001 (U.P.) India ScientistsCentral Pulp & Paper Research InstituteSaharanpur -247001 (U.P.) India

gREENSKY:A fair energy-aware optimization model for UAVs in next-generation wireless networks

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green Energy and Intelligent Transportation 2024年第1期3卷 16-24页

作者： Pratik Thantharate Anurag Thantharate Atul kulkarni School of Computing and Engineering University of MissouriKansas CityMOUSA

Unmanned Aerial Vehicles(UAVs)offer a strategic solution to address the increasing demand for cellular connectivity in rural,remote,and disaster-hit regions lacking traditional ***,UAVs’limited onboard energy storage necessitates optimized,energy-efficient communication strategies and intelligent energy expenditure to maximize *** work proposes a novel joint optimization model to coordinate charging operations across multiple UAVs functioning as aerial base *** model optimizes charging station assignments and trajectories to maximize UAV flight time and minimize overall energy *** leveraging both static ground base stations and mobile supercharging stations for opportunistic charging while considering battery chemistry constraints,the mixed integer linear programming approach reduces energy usage by 9.1%versus conventional greedy *** key results provide insights into separating charging strategies based on UAV mobility patterns,fully utilizing all available infrastructure through balanced distribution,and strategically leveraging existing base stations before deploying dedicated charging *** to myopic localized decisions,the globally optimized solution extends battery life and enhances ***,this work marks a significant advance in UAV energy management by consolidating multiple improvements within a unified coordination framework focused on joint charging optimization across UAV *** model lays a critical foundation for energy-efficient aerial network deployments to serve the connectivity needs of the future.

关键词： 5g new radio Unmanned aerial vehicles(UAV) UAV battery life Energy efficiency Unmanned aircraft systems(UAS)UAV scheduling Cellular networks Linear programming Joint UAV charging optimization

Assessing structure of Mg_(3)Bi_(2-x)Sb_(x)(0≤x≤2)at pressures below 40 gPa

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Journal of Materiomics 2024年第4期10卷 837-844页

作者： Weiwei Dong Wei Xu Zhiying guo Weishu Liu Yu Pan Satishkumar kulkarni Xiaodong Li Konstantin glazyrin Beijing Synchrotron Radiation Facility(BSRF) Institute of High Energy PhysicsChinese Academy of Sciences100049BeijingChina Deutsches Elektronen-Synchrotron DESY Notkestr.8522607HamburgGermany International Centre for Material Science Superstripes RICMASSVia dei Sabelli 119A00185RomeItaly Department of Materials Science and Engineering Southern University of Science and Technology518055ShenzhenChina Max-Planck-Institute for Chemical Physics of Solids Nöthnitzer Straße 4001187DresdenGermany Centre for X-ray and Nanoscience CXNS Deutsches Elektronen Synchrotron DESYNotkestr.8522607HamburgGermany

Mg_(3)Bi_(2-x)Sb_(x)(0≤x≤2)have gained significant attention due to their potential in thermoelectric(TE)***,there has been much debating regarding their structural properties and phase diagram as a function of pressure,which is crucial for understanding of their TE ***,we investigate a unified phase diagram of Mg_(3)(Bi,Sb)_(2) materials up to 40 gPa at room temperature using high-pressure X-ray *** high-pressure phases with the structural transition succession of P3m1→C2/m→P21/n are observed,which is valid for all Mg_(3)Bi_(2-x)Sb_(x)(0≤x≤2)*** further explore the low-pressure phase P3m1 and report that alloying does not change the quasi-isotropic compression of the unit lattice parameters nor has effect on the anisotropic bond compressibility,as recently reported for the *** study presents a comprehensive picture of Mg3Bi2–xSbx as a function of pressure and chemical composition providing a solid foundation for the future experimental and theoretical studies searching for the most efficient TE compound in Mg_(3)(Bi,Sb)_(2).

关键词： Mg_(3)Bi_(2-x)Sb_(x)(0≤x≤2) Thermoelectric High-pressure Structural evolution

Study of the Diffusion Behavior of Seawater Absorption in Multi-Walled Carbon Nanotubes/Halloysite Nanotubes Hybrid Nanofillers Modified Epoxy-Based glass/Carbon Fiber Composites

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Modern Mechanical Engineering 2024年第2期14卷 25-38页

作者： Praful Choudhari Vivek kulkarni Sanjeevakumar Khandal Department of Mechanical Engineering Sanjay Ghodawat University Atigre Kolhapur Maharashtra India

In the maritime industry, cost-effective and lightweight Fiber Reinforced Polymer (FRP) composites offer excellent mechanical properties, design flexibility, and corrosion resistance. However, their reliability in harsh seawater conditions is a concern. Researchers address this by exploring three approaches: coating fiber surfaces, hybridizing fibers and matrices with or without nanofillers, and interply rearrangement. This study focuses on evaluating the synergistic effects of interply rearrangement of glass/carbon fibers and hybrid nanofillers, specifically Multi-walled carbon nanotubes (MWCNT) and Halloysite nanotubes (HNT). The aim is to enhance impact properties by minimizing moisture absorption. Hybrid nanocomposites with equal-weight proportions of two nanofillers: 0 wt.%, 1 wt.%, and 2 wt.% were exposed to seawater for 90 days. Experimental data was subjected to modelling through the application of Predictive Fick’s Law. The study found that the hybrid composite containing 2 wt.% hybrid nanofillers exhibited a 22.10% increase in impact performance compared to non-modified counterparts. After 90 days of seawater aging, the material exhibited enhanced resistance to moisture absorption (15.74%) and minimal reduction in impact strength (8.52%) compared to its dry strength, with lower diffusion coefficients.

关键词： glass/Carbon Fiber Hybrid Composites Multiwall Carbon Nanotubes (MWCNTs) Halloysite Nanotubes (HNTs) Diffusion Behaviour Impact Properties Seawater Aging

Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： gürel Cam Ali günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200 Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(WA-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(WAAM) 3-D printing High deposition rate

Recent research in mechanical properties of geopolymer-based ultrahigh-performance concrete:A review

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Defence Technology（防务技术） 2024年第2期32卷 67-88页

作者： g.Murali Division of Research&Innovation Uttaranchal UniversityDehradun 248007India

Due to the growing need for sustainable and ultra-high-strength construction materials,scientists have created an innovative ultra-high-performance concrete called geopolymer based ultra-highperformance concrete(gUHPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fighters in border *** this context,this article reviews the fresh state and mechanical properties of ***,the ingredients of gUHPC and fresh properties such as setting time and flowability are briefly ***,the review of compressive strength,flexure strength,tensile strength and modulus of elasticity of fibrous ***,the blast and projectile impact resistance performance was ***,the microstructural characteristics were reviewed using the scanning electron microscope and X-ray Powder *** review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a higher dose of steel fibre to improve the microstructure of *** is hypothesized that the brittleness of gUHPC was mitigated by adding 1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering and *** the need for cement in gUHPC was a key factor in the review,indicating a promising potential for lowering carbon ***,gUHPC research is still in its early stages,so more study is required before its full potential can be utilized.

关键词： Mechanical properties Blast Projectile impact Fibre geopolymer Silica fume Alkaline activators

Nitrogen mineralization in the oldest climax communities in the eastern Mediterranean region

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Journal of Forestry Research 2024年第1期35卷 213-228页

作者： Fatma Selcen Sakar gürcan güleryüz Department of Biology Section Ecology GörükleGraduate School of Natural and Applied ScienceUniversity of Bursa Uludağ16059 NilüferBursaTurkey Department of Biology Section Ecology GörükleFaculty of Science and ArtsUniversity of Bursa Uludağ16059 NilüferBursaTurkey

In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest *** the oldest pure communi-ties of Pinus nigra(PN),Fagus orientalis(FO),and Abies bornmuelleriana(AB)in the mountain range of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 *** locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding capacity(%),organic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest *** had the highest annual net Nmin yield(43.9±4.8 kg ha^(-1) a^(-1)),*** the lowest(30.5±4.2 kg ha^(-1) a^(-1)).Our findings show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling and that hydrolyzed tannic acids and total phenolic compounds effectively control N *** acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification.

关键词： Oldest forest communities Nitrogen mineralization Nitrification Tannic acid Total phenolic Litter

Shell-model representations of the microscopic version of the Bohr-Mottelson collective model

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Communications in Theoretical Physics 2024年第8期76卷 79-90页

作者： H g ganev Joint Institute for Nuclear Research DubnaRussia Institute of Mechanics Bulgarian Academy of SciencesSofiaBulgaria

The structure of the irreducible collective spaces of the group Sp(12,R),which many-particle nuclear states are classified according to the chain Sp(12,R)⊃U(6)⊃SO(6)⊃SU_(pn)(3)⊗SO(2)⊃SO(3)of the proton-neutron symplectic model(PNSM),is considered in *** chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr-Mottelson collective *** construction of the relevant shell-model representations of the Sp(12,R)group along this chain is considered for three nuclei with varying collective properties and from different mass *** is shown that the SU_(pn)(3)basis states of the Sp(12,R)representations belonging to the SO(6)irreps with seniorityυ≥υ0,withυ0 denoting the maximal seniority SO(6)irrep contained in the Sp(12,R)bandhead,are always Pauli allowed,but organized in a different way into different SO(6)*** is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm *** the SU_(pn)(3)multiplets withinυ<υ0 are not all Pauli forbidden,it is safe to discard *** results obtained in the present work are important for the practical application of the microscopic version of the Bohr-Mottelson collective model.

关键词： microscopic shell-model version of the Bohr-Mottelson model proton-neutron symplectic model Sp(12,R)dynamical algebra shell-model representations

Harmonics in the Squirrel Cage Induction Motor Analytic Calculation Part III: Influence on the Torque-speed Characteristic

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 86-102页

作者： g.Kovács the ganz Electric Works BudapestHungary

The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. Relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the ***, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end.

关键词： Asynchronous parasitic torques Induction motor Squirrel cage rotor Space harmonics Synchronous parasitic torques