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Science in China,Ser.B 1987年第12期30卷 1233-1246页

作者：赵德杰 p.n.gates p.S.JOnES Department of Chemistry Wuhan University Royal Holloway College University of London

The reactions of alkynes with dichloroborane-dimethyl sulfide （HBCl2·SMe2） in the presence of boron trichtoride in pentane have been *** internal and terminal alkynes react with HBCl2·SMe2 in the molar ratio 1:2 at 0℃ to give dihydroborating products, gem-bis （dichloroboryl）alkanes, in good yield. Since the dihydroboration of alkynes is suppressed considerably at lower temperature, the internal alkynes and HBCl2·SMe2 react quantitatively in the molar ratio 1.4:1 at-20℃ or -30℃ to give the expected *** the same conditions,the terminal alkynes, however, undergo both monohydroboration and *** terminal alkynes react with boron trichloride in the molar ratio 1 :1.1 in pentane, the chloroborating products, 2-chloro-1-alkenyldichloroboranes have been obtained in high *** dichloroboranes are readily converted by alcoholysis into the corresponding boronic *** resulting compounds have been characterized by IR, 1H,11B, and 13C n

关键词： ppm SM BCI HYDROBORATIOn OF ALKYnES WITH DICHLOROBORAnE-DIMETHYL SULFIDE SYnTHESES AnD SpECTROSCOpIC CHARACTERISTICS OF gem-DIBOROn AnD ALKEnYLBOROn COMpOUnDS OCH HBC

炔烃与二氯硼烷-甲硫醚的硼氢化反应——偕-二硼和烯基硼化合物的合成和光谱特性

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中国科学(B辑化学生物学农学医学地学) 1987年第3期 245-256页

作者：赵德杰 p.n.gates p.S.Jones 武汉大学化学系英国London大学皇家Holloway学院

本文研究了在三氯化硼存在下,炔烃与二氯硼烷-甲硫醚（HCCl2·SMe2）的硼氢化反应。内炔烃和端炔烃与HBCl2·SMe2（摩尔比为1:2）在0℃反应,得到了高产率的双硼氢化产物——偕-双（二氯硼基）烷烃。在较低温度下,双硼氢化被显著地抑制... 详细信息

本文研究了在三氯化硼存在下,炔烃与二氯硼烷-甲硫醚（HCCl2·SMe2）的硼氢化反应。内炔烃和端炔烃与HBCl2·SMe2（摩尔比为1:2）在0℃反应,得到了高产率的双硼氢化产物——偕-双（二氯硼基）烷烃。在较低温度下,双硼氢化被显著地抑制。因此,在—20℃或—30℃下,内炔烃与HBCl2·SMe2（1.4:1）反应,定量地生成预期的烯基二氯硼烷。但在同样条件下,端炔烃既进行单硼氢化,也会经历硼氯化反应。当端炔烃在戊烷中与三氯化硼（1:1。1）反应时,高产率地得到硼氯化产物——2-氯-1-烯基二氯硼烷。各取代二氯硼烷易于醇解为相应的硼酸酯。所得化合物经IR,1H,11B,或13C nMR表征。讨论了化合物的结构和它们的波谱特性之间的关系。基于化学位移,确证分子中的π-电子或孤对电子和硼原子的空ρ-轨道存在着明晰的（pp）π-相互作用。

关键词：炔烃 HBC 三氯化硼脂肪族不饱和烃硼化合物 ⅢA族化合物硼氢化反应甲硫醚氯硼烷

Impact of interfacial tension on oil-water flow in a narrow gap

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petroleum Research 2024年第2期9卷 219-227页

作者： Salim Raza Ian D.gates Saira Sherin University of Engineering and Technology PeshawarPakistan Department of Chemical and petroleum Engineering Schulich School of EngineeringUniversity of CalgaryCanada

numerous researchers have examined the co-current flow of oil-water and aqueous solutions containing polymers and surfactants in thin gaps for oil *** some have focused on charges and forces at the interfaces of oil-surfactant solutions during *** study of flow structures,interface behavior,and relative permeabilities of oil and aqueous phases of surfactant flow through thin gaps has been less *** the first time,this research aims to comprehensively investigate the flow of oil-water and oil-surfactant solutions through a thin gap(Hele-Shaw cell)with a particular focus on the impact of sodium dodecyl sulfate(SDS).The experiments reveal that SDS forms an emulsion near the oil-water interface,capturing oil droplets and enabling their flow along with the SDS *** studies confirm this,showing that when SDS contacts oil,it creates channels through the oil phase,leading to the accumulation and division of oil into small round-shaped droplets,resulting in an oil-in-water *** addition of SDS to the injecting water significantly enhances relative permeabilities,leading to a remarkable 90%increase in oil recovery from the *** research suggests that the optimal SDS concentration range for maximum oil recovery is between 1.5 and 2 wt%,as it achieves the minimum interfacial tension between oil and water.

关键词： Surfactant Co-current flow narrow gap Interface interactions Relative permeability

Stochastic Ranking Improved Teaching-Learning and Adaptive Grasshopper Optimization Algorithm-Based Clustering Scheme for Augmenting network Lifetime in WSns

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China Communications 2024年第9期21卷 159-178页

作者： n Tamilarasan SB Lenin p Mukunthan nC Sendhilkumar Department of Electronics and Communications Engineering Sri Indu College of Engineering and TechnologyHyderabadTelanganaIndia Department of Electronics and Communications Engineering Sri Manakula Vinayagar Engineering CollegePondicherryIndia

In Wireless Sensor networks(WSns),Clustering process is widely utilized for increasing the lifespan with sustained energy stability during data *** clustering protocols were devised for extending network lifetime,but most of them failed in handling the problem of fixed clustering,static rounds,and inadequate Cluster Head(CH)selection criteria which consumes more *** this paper,Stochastic Ranking Improved Teaching-Learning and Adaptive Grasshopper Optimization Algorithm(SRITL-AGOA)-based Clustering Scheme for energy stabilization and extending network *** SRITL-AGOA selected CH depending on the weightage of factors such as node mobility degree,neighbour's density distance to sink,single-hop or multihop communication and Residual Energy(RE)that directly influences the energy consumption of sensor *** specific,Grasshopper Optimization Algorithm(GOA)is improved through tangent-based nonlinear strategy for enhancing the ability of global *** the other hand,stochastic ranking and violation constraint handling strategies are embedded into Teaching-Learning-based Optimization Algorithm(TLOA)for improving its exploitation ***,SR and VCH improved TLOA is embedded into the exploitation phase of AGOA for selecting better CH by maintaining better balance amid exploration and *** results confirmed that the proposed SRITL-AGOA improved throughput by 21.86%,network stability by 18.94%,load balancing by 16.14%with minimized energy depletion by19.21%,compared to the competitive CH selection approaches.

关键词： Adaptive Grasshopper Optimization Algorithm(AGOA) Cluster Head(CH) network lifetime Teaching-Learning-based Optimization Algorithm(TLOA) Wireless Sensor networks(WSns)

Calibration of the DEM sliding friction and rolling friction parameters of a cohesionless bulk material

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particuology 2024年第9期92卷 126-139页

作者： Jonatan Marín pérez Tugrul Comlekci Yevgen Gorash Donald MacKenzie University of Strathclyde 75 Montrose StreetG11XJGlasgowUnited Kingdom

The discrete element method(DEM)has become a valuable tool for understanding the mechanical behaviour of granular assemblies,however,the accuracy of the DEM simulations depends on several interaction parameters such as the sliding friction and rolling friction ***,these parameters are estimated using bulk calibration approach(BCA)where the draw down test has been suggested as an effective way to approach these *** test provides up to four bulk criteria,the angle of repose,shear angle,mass flow rate and the mass loss which are used to narrow down the possible ***,there is still more research needed around it to fully understand how this methodology *** experimental and numerical study was carried out using the draw down test to assess the influence of different mass flow rates and particle shapes on DEM parameters for a cohesionless bulk *** is concluded that use of multi-sphere particles and three aperture sizes in the draw down test to calibrate the sliding and rolling friction parameters of a cohesionless bulk material can converge to a small feasible region in which a single combination of the friction coefficients can be *** calibrated sliding and rolling friction coefficients were validated using multi-sphere particles,where the maximum deviation was 5.9%from the experimental values.

关键词： Discrete element method Calibration Draw down Sliding friction Rolling friction particle shape

In-situ study of the microstructure evolution during tension of a Mg-Y-Zn-Al alloy processed by rapidly solidified ribbon consolidation technique

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Journal of Magnesium and Alloys 2024年第5期12卷 2024-2040页

作者： Jeno Gubicza Kristián Máthis péter nagy péter Jenei Zoltán Hegedus Andrea Farkas Jozef Vesely Shin-ichi Inoue Daria Drozdenko Yoshihito Kawamura Department of Materials physics Faculty of ScienceEotvos Loránd UniversityPázmány P.sétány 1/ABudapest H-1117Hungary Department of physics of Materials Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116 Praha 2Czech Republic Deutsches Elektronen-Synchrotron DESY Notkestr.85Hamburg 22603Germany Magnesium Research Center Kumamoto University2-39-1 KurokamiChuo-kuKumamoto 860-8555Japan

Mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation(RSRC)technique exhibit an exceptional mechanical performance indicating promising application *** material has a bimodal microstructure consisting of fine recrystallized and coarse non-recrystallized grains with solute-rich stacking faults forming cluster arranged layers(CALs)and nanoplates(CAnaps),or complete long period stacking ordered(LpSO)*** order to reveal the deformation mechanisms,in-situ synchrotron X-ray diffraction line profile analysis was employed for a detailed study of the dislocation arrangement created during tension in Mg-0.9%Zn-2.05%Y-0.15%Al(at%)*** uncovering the effect of the initial microstructure on the mechanical performance,additional samples were obtained by annealing of the as-consolidated specimen at 300 and 400℃ for 2 *** heat treatment at 300℃ had no significant effect on the initial microstructure,its evolution during tension and,thus,the overall deformation behavior under tensile *** the other hand,annealing at 400℃ resulted in a significant increase of the recrystallized grains fraction and a decrease of the dislocation density,leading to only minor degradation of the mechanical *** maximum dislocation density at the failure of the samples corresponding to the plastic strain of 10-25% was estimated to be about 16-20×10^(14)m^(-2).The diffraction profile analysis indicated that most dislocations formed during tension were of non-basal and pyramidal types,what was also in agreement with the Schmid factor values revealed independently from orientation *** was also shown that the dislocation-induced Taylor hardening was much lower below the plastic strain of 3% than above this value,which was explained by a model of the interaction between prismatic dislocations and CAnaps/LpSO plates.

关键词： Mg-Zn-Y-Al alloy Long period stacking ordered(LpSO)phase Cluster arranged nanoplates(CAnaps) Annealing Tension Dislocation density Hardening

Effects of site preparation methods on soil physical properties and outplanting success of coniferous seedlings in boreal forests

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Journal of Forestry Research 2024年第2期35卷 70-80页

作者： Aleksey S.Ilintsev Elena n.nakvasina Alexander p.Bogdanov northern Research Institute of Forestry 13 Nikitova Str.Arkhangelsk 163062Russian Federation Department of Silviculture and Forest Management Northern(Arctic)Federal University Named After M.V.LomonosovSevernoy Dviny Emb.17Arkhangelsk 163002Russian Federation

This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of *** study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling survival;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess *** the rooting layer,240 soil samples were taken to determine physical *** study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina ***,reduced soil moisture was noted,particularly in mounds,resulting in increased *** Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the *** treatment in polytrichum sites resulted in reduced soil moisture and increased aeration *** the Myrtillus and polytrichum sites,patch scarification had no effects on physical *** polytrichum sites,survival rates,heights,and heigh increments of bareroot norway spruce seedlings in mounds were higher than in patches;however,the same did not apply to *** Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil *** conditions and soil types should be considered when applying different soil treatment methods to ensure high survival rates and successful seedling growth.

关键词： Boreal forests Mechanical site preparation patch scarification Mounding Soil properties Containerised seedlings Bareroot seedlings

RBC aggregation,deformation and adhesion to endothelium:Role of nitric oxide derived from L-Arginine and sodium nitroprusside

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 53-65页

作者： M.K.Maksimov p.B.Ermolinskiy O.n.Scheglovitova n.n.Sklyankina A.V.Muravyov A.E.Lugovtsov A.V.priezzhev Faculty of physics M.V.Lomonosov Moscow State University bld.1subbuilding.2Leninskie goryMoscow 11991Russia n.F.Gamaleya national Research Center for Epidemiology and Microbiology 18 Gamaleya StreetMoscow 123098Russia K.D.Ushinsky Yaroslavl State pedagogical University 108/1 Respublikanskaya StreetYaroslavl 150000Russia

Red blood cells(RBCs)are the most abundant human blood *** aggregation and deformation strongly determine blood viscosity which impacts hemorheology and *** turn,RBC properties depend on di®erent endogenous and exogenous *** such factor is nitric oxide(nO),which is mainly produced by endothelial cells(EC)from L-arginine amino acid in the circulatory *** the mechanisms of the RBC-endothelium interplay are not clear up to date and considering its possible clinical importance,the aims of this study are to investigate in vitro:(1)The e®ect of L-arginine induced nO on RBC aggregation and adhesion to endothelium;(2)the nO e®ect on RBC aggregation and deformation induced by L-arginine and sodium nitroprusside without the presence of endothelium in the *** RBC aggregation and adhesion to a monolayer of EC were studied using optical tweezers(OT).The RBC deformability and aggregation without endothelium in the samples were studied using the°ow chamber method and Myrenne *** con¯rmed that nO increases deformability and decreases aggregation of *** showed that the soluble guanylate cyclase pathway appears to be the only nO signaling pathway *** the samples with the endothelium,the\bell-shaped"dependence of RBC aggregation force on L-arginine concentration was observed,which improves our knowledge about the process of nO production by ***,data related to L-arginine accumulation by endothelium were obtained:necessity of the presence of extracellular L-arginine stated by other authors was put under *** our study,nO decreased the RBC-endothelium adhesion,however,the tendency appeared to be weak and was not con¯rmed in another set of *** our knowledge,this is the¯rst attempt to measure the forces of RBC adhesion to endothelium monolayer with OT.

关键词： Red blood cells aggregation L-arginine endothelium optical tweezers Myrenne flow chamber

Stability Analysis of DC Microgrid Clusters Based on Step-by-step System Matrix Building Algorithm

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Journal of Modern power Systems and Clean Energy 2024年第3期12卷 900-912页

作者： K.Jithin n.Mayadevi R.Hari Kumar V.p.Mini the Department of Electrical Engineering College of Engineering TrivandrumAPJ Abdul Kalam Technological University(APJAKTU)ThiruvananthapuramIndia

DC microgrids(DCMGs)are made up of a network of sources and loads that are connected by a number of power electronic converters(pECs).The increase in the number of these pECs instigates major concerns in system *** interconnecting the microgrids to form a cluster,the system stability must be *** paper proposes a novel stepby-step system matrix building(SMB)algorithm to update the system matrix of an existing DCMG cluster when a new microgrid is added to the cluster through a distribution *** stability of the individual DCMGs and the DCMG cluster is analyzed using the eigenvalue ***,the particle swarm optimization(pSO)algorithm is used to retune the controller gains if the newly formed cluster is not *** simulation of the DCMG cluster is carried out in MATLAB/Simulink environment to test the proposed *** results are also validated using the Op4510 real-time simulator(RTS).

关键词： Converter DC microgrid cluster eigenvalue interconnection particle swarm optimization system stability system matrix

Wettability,reactivity,and interface structure in Mg/ni system

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Journal of Magnesium and Alloys 2024年第2期12卷 659-672页

作者： S.Terlicka n.Sobczak Ł.Maj p.Darłak J.J.Sobczak Institute of Metallurgy and Materials Science Polish Academy of Sciences25 Reymonta Str.KrakowPoland Faculty of Foundry Engineering AGH University23 Reymonta Str.KrakowPoland

The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure ni *** comparison,the experiments were performed in two variants:(1)using the Capillary purification(Cp)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(CH)*** high-temperature tests were performed under isothermal conditions(Cp:760℃for 30 s;CH:715℃for 300 s)using Ar+5 wt%H_(2) *** the sessile drop tests,images of the Mg/ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate *** and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified *** was found that an oxide-free Mg drop obtained by the Cp procedure showed a wetting phenomenon on the ni substrate(an average contact angleθnpreading and good wetting over the ni substrate(θ_((Cp))~20°in 5 s)to form a final contact angle ofθ_(f(Cp))~18°.In contrast,a different wetting behavior was observed for the CH procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test ***,in both cases,the deep craters formed in the ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-ni alloys suggest a strong dissolution of ni in liquid Mg and apparent values of the final contact angles measured for the Mg/ni system.

关键词： Magnesium-based alloys Sessile drop tests Capillary purification procedure Wettability Reactivity Contact angle