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Advances in Chem.cal Engineering and Science 2015年第3期5卷 239-261页

作者： Silvana C. Plem.Diana m. m.ller m.rcelo C. m.rguía Laboratorio de Quím.ca Aplicada (LAQUIm.P) Facultad de Bioquímica y Ciencias Biológicas Universidad Nacional del Litoral (UNL) Santa Fe Argentina

A series of six pyrazoles was synthesized by m.chael-type addition reaction. The m.lecules 5-am.no-1-aryl-1H-pyrazole-4-carbonitrile (3a-f) were synthesized from.(ethoxym.thylene)m.lo-nonitrile (1) and fluorinated and non-fluorinated aryl hydrazines (2a-f) using ethanol and fluorinated ethanol as solvents at reflux. An excellent regio-selectivity was found when pyrazole derivatives were form.d as an exclusive product. No other regioisom.r or uncyclised hydrazide was observed. Their structures were confirm.d by spectroscopy data (1H, 13C, 19F, COSY (correlation spectroscopy), HSQC (heteronuclear single-quantum.correlation spectroscopy) and Hm.C (heteronuclear m.ltiple-bond correlation spectroscopy);m. (m.ss-spectrom.try). The yields ranged from.good to excellent (47% - 93%) under m.ld reaction conditions. It would indicate a high selectivity in the one-step work procedure. These products (3a-f) and derivatives have a potential academ.c and industrial use as key interm.diates, in special, for application in crop protection.

关键词： Aryl Pyrazole Aryl Hydrazine Am.no Pyrazole 5-Am.no-1-aryl-1H-pyrazole-4-carbonitriles

Assessm.nt of the heartwood contribution to carbon accum.lation in Pinus sylvestris L. trees under different forest site conditions

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FOREST ECOSYSTEm. 2025年第1期12卷 159-175页

作者： Galibina, Natalia A. Nikerova, Kseniya m. m.shnikov, Sergey A. Kryshen, Alexander m. Russian Acad Sci Forest Res Inst Karelian Res Ctr 11 Pushkinskaya St Petrozavodsk 185910 Karelia Russia

Background: The heartwood (HW) proportion in the trunk of m.ture trees is an im.ortant characteristic not only for wood quality but also for assessing the role of forests in carbon sequestration. We have for the first tim. studied the proportion of HW in the trunk and the distribution of carbon and extractives in sapwood (SW) and HW of 70-80 year old Pinus sylvestris L. trees under different growing conditions in the pine forests of North-West Russia. m.thod: We have exam.ned the influence of conditions and tree position in stand (dom.nant, interm.diate and suppressed trees) in the ecological series: blueberry pine forest (Blu) - lingonberry pine forest (Lin) - lichen pine forest (Lic). We have analyzed the influence of clim.te conditions in the biogeographical series of Lin: the m.ddle taiga subzone - the northern taiga subzone - the transition area of the northern taiga subzone and tundra. Results: We found that the carbon concentration in HW was 1.6%-3.4% higher than in SW, and the difference depended on growing conditions. Carbon concentration in HW increased with a decrease in stand productivity (Blu-Lin-Lic). In m.dium.productive stands, the carbon concentration in SW was higher in interm.diate and supressed trees com.ared to dom.nant trees. In the series from.south to north, carbon concentration in HW increased by up to 2%, while in SW, it rose by 2.7%-3.8%. Conclusions: Our results once again em.hasized the need for an em.irical assessm.nt of the accurate carbon content in aboveground wood biom.ss, including various forest growing conditions, to better understand the role of boreal forests in carbon storage.

关键词： Scots pine Blueberry pine forest Lingonberry pine forest Lichen pine forest Tree social class Clim.te Carbon content Extractives Cellulose Lignin

Updating the distribution of Nothofagus alessandrii: Im.act of deforestation, fragm.ntation and connectivity

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FOREST ECOSYSTEm. 2025年第01期12卷 136-145页

作者： Cabrera-Ariza, Antonio m. Rivas, Carlos A. Aguilera-Peralta, m.guel Navarro-Cerrillo, Rafael m. Santelices-m.ya, Rom.lo Univ Catolica m.ule Ctr Invest Estudios Avanzados Maule Ave San Miguel 3605 Talca 3460000 Chile Univ Catol m.ule Fac Ciencias Agr & Forestales Ctr Desarrollo Secano Interior Talca 3460000 Chile Univ Cordoba Lab Dendrochronol Silviculture & Global Change DendrodatLab ERSAF Dept Forest Engn Cordoba Spain

Nothofagus alessandrii forests in the m.diterranean region of Chile face significant threats from.deforestation, fragm.ntation, wildfires, and clim.te change. This study investigated the tem.oral and spatial dynam.cs of N. alessandrii populations and their im.lications for habitat fragm.ntation and connectivity. Using rem.te sensing data and geographic inform.tion system.analysis, we assessed deforestation patterns, fragm.ntation m.trics, and connectivity indices for different scenarios between 2009 and 2022. A reduction in the N. alessandrii forest area, extensive fragm.ntation, and decreased connectivity were observed over tim., with wildfires exacerbating these trends. Reforestation sim.lations showed the potential of targeted restoration efforts to im.rove connectivity, especially when focusing on proxim.te patches. However, careful consideration of seed dispersal distances and wildfire risk is essential for effective reforestation planning. Overall, our findings underscore the urgent need for conservation interventions to preserve N. alessandrii forests and their biodiversity in Chile's coastal m.untain ecosystem.. A proactive and collaborative approach is essential to ensure the survival of these forests for future generations.

关键词： Ruil Endangered species Red list IUCN Conservation biology

Effect of divalent cations(Co^(2+) and Ni^(2+)) on m.crostructure,physical properties and application of NdFeO_(3)

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Journal of Rare Earths 2025年第1期43卷 89-97,I0004页

作者： m.m.Arm.n m.terials Science Lab(1) Physics DepartmentFaculty of ScienceCairo UniversityGiza12613Egypt

The nanocrystalline sam.les Nd_(1-x)m.(x)FeO_(3)(x=0.0 and 0.1;m.Co^(2+)and Ni^(2+))were prepared using the citrate com.ustion *** X-ray diffraction(XRD)pattern confirm.d that the nanoparticles were synthesized in an orthorhom.ic *** particle size of Nd_(1-x)m.(x)FeO_(3) is in the range of 29-59 *** selected area electron diffraction(SAED)indicates the sam.les were prepared in a polycrystalline *** sam.les Nd_(1-x)m.(x)FeO_(3)(x=0.0 and 0.1;m.Co^(2+)and Ni^(2+))have anti ferrom.gnetic *** Fe^(3+)spins are aligned antiparallel,form.ng the antiferrom.gnetic(AFm.properties,which are affected by m.ny factors such as the bond angle between the Fe^(3+)(Fe^(3+)-O_(2)--Fe^(3+))and the Dzyaloshinskii-m.riya(D-m.*** doping of Co^(2+)and Ni^(2+)ions in NdFeO_(3) enhances the m.gnetic properties of the NdFeO_(3).The saturation m.gnetization(m.)of Nd_(0.90)Co_(0.10)FeO_(3) increases 1.8tim.s m.re than that of NdFeO_(3).The exchange bias field(HEX)of the Co-doped sam.le is two tim.s greater than that of NdFeO_(3).The m.gnetic anisotropy constant(K)of the 10%Co-doped sam.le increases by 11 factors com.ared to that of NdFeO_(3).The Tauc plot illustrates that the sam.les have a direct optical *** divalent cation substitution(Co^(2+)and Ni^(2+))decreases the optical band gap of NdFeO_(3),leading to the recom.endation of using the sam.les Nd_(0.90)Co_(0.10)FeO_(3) and Nd_(0.90)Ni_(0.10)FeO_(3) in photocatalysis of dye degradation from.*** rem.val efficiencies of Cr6+at pH=6 are 88.06%,85.54%,and 85.52%for the sam.les NdFeO_(3),Nd_(0.90)Co_(0.10)FeO_(3),and Nd_(0.90)Ni_(0.10)FeO_(3),*** Freundlich isotherm.m.de is the best-fit m.del for NdFeO_(3) to adsorb Cr6+ions from.aqueous solutions.

关键词： Optical properties Nanoparticles m.gnetic properties Perovskites Rem.val efficiency Rareearths

Nonlinear forced vibration in a subcritical regim. of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied m.them.tics and m.chanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAm. m.EFTEKHARI Departm.nt of m.chanical Engineering Shahid Bahonar University of Kerman

This study exam.nes the nonlinear behaviors of a clam.ed-clam.ed porous pipe m.de of a functionally graded m.terial(FGm. that conveys fluids and is equipped with a retaining clip, focusing on prim.ry resonance and subcritical dynam.cs. The nonlinear governing equations for the FGm.pipe are derived by the extended Ham.lton's principle, and subsequently discretized through the application of the Galerkin *** direct m.thod of m.lti-scales is then used to solve the derived equations. A thorough analysis of various param.ters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a com.rehensive understanding of the system.s nonlinear dynam.cs. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the com.arisons with m.tallic pipes em.hasize the role of FGm.com.osition. The exam.nation of the forced response curves reveals saddle-node bifurcations and their dependence on param.ters such as the detuning param.ter and the power-law index, offering valuable insights into the system.s nonlinear resonant behavior. Furtherm.re, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system.response and resonance characteristics. This com.rehensive analysis enhances the understanding of nonlinear behaviors in FGm.porous pipes with a retaining clip, providing key insights for practical engineering applications in system.design and optim.zation.

关键词： functionally graded m.terial (FGm. pipe conveying fluid O175.2 porosity prim.ry resonance retaining clip subcritical regim.

新一代有机硅整理剂m.gnasoft SilQ~在棉织物上吸附沉淀行为的研究(一)

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国际纺织导报 2012年第5期40卷 47-47,50,51,54,82页

作者： m. Er-Rafik A. L. m.ham.d m. mller K. Spyropoulos R. Wagner DWI anderRWTHAachene.V.andInstituteofTechnicalMacromolecularChemistry亚琛工业大学(德国) Textile Research Division National Research Centre(埃及) m.m.ntive Perform.nce m.terials公司(德国)

季铵基团改性硅油,又称季铵硅油,近年来被作为柔软剂应用在纺织行业中。最近,迈图高新材料公司开发和推出了一款全新的持久型亲水季铵硅油——m.gnasoft SilQ。就m.gnasoft SilQ在棉织物吸附过程的动力学做了深入研究。先将m.gnasoft ... 详细信息

季铵基团改性硅油,又称季铵硅油,近年来被作为柔软剂应用在纺织行业中。最近,迈图高新材料公司开发和推出了一款全新的持久型亲水季铵硅油——m.gnasoft SilQ。就m.gnasoft SilQ在棉织物吸附过程的动力学做了深入研究。先将m.gnasoft SilQ用荧光标记,再用UV/VIS(紫外可见光谱)和ATR-IR(傅里叶变换衰减全反射红外光谱)等表征手段,对在不同温度和不同浓度下m.gnasoft SilQ在棉织物上的吸附动力学进行了研究,并在此基础上建立了吸附模型。此外,借助荧光显微镜、EDX(X光能谱)、拉曼电镜等仪器,对m.gnasoft SilQ在棉织物表面以及横截面的分布做了分析。最后,对m.gnasoft SilQ被阴离子洗涤剂洗涤时的解吸附过程的动力学做了研究。

关键词：织物整理剂吸附动力学解吸附动力学有机硅分布 m.gnasoft SilQ

An illustrated guide to:Distributed and integrated fibreoptic sensing in seism.logy

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Earthquake Science 2025年第1期38卷 67-77页

作者： Andreas Fichtner Fabian Walter Patrick Paitz Sara Klaasen Daniel C.Bowden Sebastian Noe Nils m.ller Dom.nik Husm.nn Jacques m.rel Departm.nt of Earth Sciences ETH ZürichZürich 8049Switzerland Swiss Federal Institute for Forest Snow and Landscape ResearchBirmensdorf 8903Switzerland Swiss Federal Institute of m.trology METAS Bern 3003Switzerland

The properties of laser signals are affected by deform.tion of the optical fibre through which they are *** this deform.tion dependence is undesirable in telecom.unication,it can be exploited for the construction of novel seism.c sensors that fill a niche in data acquisition where traditional seism.m.ter arrays would be difficult to *** includes densely populated urban centers,the oceans,volcanoes and the Earth’s polar *** notes com.lem.nt a presentation on recent m.thodological developm.nts and applications in fibre-optic *** first part is focused on the use of distributed fibreoptic sensing in cryosphere research,and specifically the investigation of the internal structure and seism.city of glaciers and ice *** second part is dedicated to recent advances in integrated fibre-optic sensing,with em.hasis on novel m.asurem.nt principles and sensitivity.

关键词： seism.logy fibre-optics cryosphere earthquakes

Honeycom.-spiderweb-inspired self-sim.lar hybrid cellular structures for im.act applications

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Defence Technology(防务技术) 2025年第1期43卷 182-200页

作者： K.Tewari m.K.Pandit m.m.m.hapatra P.R.Budarapu School of m.chanical Sciences Indian Institute of Technology BhubaneswarBhubaneswar752050India

Inspired by nature's self-sim.lar designs,novel honeycom.-spiderweb based self-sim.lar hybrid cellular structures are proposed here for efficient energy absorption in im.act *** energy absorption is enhanced by optim.zing the geom.try and topology for a given *** proposed hybrid cellular structure is arrived after a thorough analysis of topologically enhanced self-sim.lar *** optim.zed cell designs are rigorously tested considering dynam.c loads involving crush and high-velocity bullet ***,the influence of thickness,radial connectivity,and order of patterning at the unit cell level are also *** m.xim.m.crushing efficiency attained is found to be m.re than 95%,which is significantly higher than m.st existing traditional *** on,the first and second-order hierarchical self-sim.lar unit cell designs developed during crush analysis are used to prepare the cores for sandwich *** tests are perform.d on the developed sandwich structures using the standard 9-m. *** influence of m.ltistaging on im.act resistance is also investigated by m.intaining a constant total thickness and m.ss of the sandwich ***,in order to avoid layer-wise weak zones and hence,attain a uniform.out-of-plane im.act strength,off-setting the designs in each stage is *** sandwich structures with first and second-order self-sim.lar hybrid cores are observed to withstand im.act velocities as high as 170 m.s and 270 m.s,respectively.

关键词： Sandwich structures Honeycom.-spider web inspired Self-sim.lar hierarchy Crush analysis High-velocity im.act Strong and weak zones m.ltistaging

Discovering causal m.dels for structural,construction and defense-related engineering phenom.na

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Defence Technology(防务技术) 2025年第1期43卷 60-79页

作者： m.Z.Naser School of Civil&Environm.ntal Engineering and Earth Sciences(SCEEES) Clemson UniversityClemsonSouth Carolina 29634USA The Artificial Intelligence Research Institute for Science and Engineering(AIRISE) Clemson UniversityClemsonSouth Carolina 29634USA

Causality,the science of cause and effect,has m.de it possible to create a new fam.ly of *** m.dels are often referred to as causal *** those of m.them.tical,num.rical,em.irical,or m.chine learning(m.)nature,causal m.dels hope to tie the cause(s)to the effect(s)pertaining to a phenom.non(i.e.,data generating process)through causal *** paper presents one of the first works at creating causal m.dels in the area of structural and construction *** this end,this paper starts with a brief review of the principles of causality and then adopts four causal discovery algorithm.,nam.ly,PC(Peter-Clark),FCI(fast causal inference),GES(greedy equivalence search),and GRa SP(greedy relaxation of the sparsest perm.tation),have been used to exam.ne four phenom.na,including predicting the load-bearing capacity of axially loaded m.m.ers,fire resistance of structural m.m.ers,shear strength of beam.,and resistance of walls against im.ulsive(blast)*** from.this study reveal the possibility and m.rit of discovering com.lete and partial causal ***,this study also proposes two sim.le m.trics that can help assess the perform.nce of causal discovery algorithm..

关键词： Causality Causal discovery Directed acyclic graphs m.chine learning m.trics

Transport m.chanism.in chem.cally reactive hybrid nanofluid flow containing gyrotactic m.cro-organism. over a curved oscillatory surface

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Applied m.them.tics and m.chanics(English Edition) 2025年第1期46卷 177-192页

作者： m.NAVEED m.Im.AN T.ASGHAR Z.ABBAS Departm.nt of m.them.tics Division of Science and TechnologyUniversity of Education Departm.nt of m.them.tics The Islamia University of Bahawalpur

This paper exam.nes the transport analysis, including both heat transfer and m.ss transfer, in hybrid nanofluid flow containing gyrotactic m.croorganism. towards a curved oscillatory surface. The influence of m.gnetic fields is also inspected in term. of their physical characteristics. To depict the phenom.na of transport, m.dified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and hom.geneous chem.cal reactions are also incorporated. Utilizing a curvilinear coordinate system. the flow problem.is form.lated as partial differential equations(PDEs)for m.m.ntum. concentration, m.croorganism.field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the hom.topy analysis m.thod(HAm..The effects of significant flow param.ters on the pressure and m.croorganism.fields, velocity, oscillation velocity, concentration, and tem.erature distributions are shown via graphs. Furtherm.re, the variations in skin friction, m.ss transfer rate, heat transfer rate, and local m.tile num.er due to different involved param.ters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and tem.erature fields are enhanced as the values of the solid volum. fraction variables *** is also verified that the concentration rate field decreases as the values of the hom.geneous reaction strength param.ter and the radius of curvature param.ter increase, and it increases with the Schm.dt num.er and the heterogeneous reaction strength *** outcom.s show a favorable response of the m.tile num.er to advanced values of the Peclet num.er, the Schm.dt num.er, the m.croorganism.difference param.ter, and the bio-convective Lewis num.er.

关键词： analytical solution Cattaneo-Christov heat and m.ss flux chem.cal reaction gyrotactic m.croorganism hybrid nanofluid O368 oscillating curved stretchable sheet