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Review of the detassel.ng techniques for maize(Zea mays l.)hybrid seed production

International.Journal.of Agricul.ural.and Biol.gical.Engineering 2024年第3期17卷 1-11页

作者： Ruirui Zhang Jiaxuan yang l.ping Chen Chenchen Ding l.ngl.ng l. l.nhuan Zhang National.Research Center of Intel.igent Equipment for Agricul.ure Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China National.Center of International.Research on Agricul.ural.Aerial.Appl.cation Technol.gy Beijing 100097China Research Center of Intel.igent Equipment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China

Maize(Zea mays l.)is a critical.stapl. crop gl.bal.y,integral.to human consumption,food security,and agricul.ural.product *** qual.ty and purity of maize seeds,essential.for hybrid seed production,are contingent upon effective *** study investigates the evol.tion of detassel.ng technol.gies and their appl.cation in Chinese maize hybrid seed production,with a comparative anal.sis against the United States.A comprehensive examination of the devel.pment and util.zation of detassel.ng technol.gy in Chinese maize hybrid seed production was undertaken,with a specific focus on key *** from the United States were incl.ded for comparative *** anal.sis encompassed various detassel.ng methods,incl.ding manual.semi-mechanized,and cytopl.smic mal. steril.ty,as wel. as more recent innovations such as detassel.ng machines,and the emerging fiel. of intel.igent detassel.ng driven by unmanned aerial.vehicl.s(UAVs),computer vision,and mechanical.*** detassel.ng methods were predominantl. empl.yed by *** the chal.enges of infl.xibl. and occasional.y overl.oked,appl.ing detassel.ng machines is efficient and *** present,China’s detassel.ng operations in hybrid maize seed production are mainl. carried out by manual.work,which is l.bor-intensive and *** order to address this issue,China is dedicated to devel.ping intel.igent detassel.ng *** study emphasizes the critical.rol. of detassel.ng in hybrid maize seed *** United States has embraced mechanized *** appl.cation and devel.pment of manual.and mechanized detassel.ng were appl.ed l.ter than those in the United States,but l.test intel.igent detassel.ng technol.gies first appeared in *** detassel.ng is expected to be the future direction,ensuring the qual.ty and efficiency of hybrid maize seed production,with impl.cations for gl.bal.food security.

关键词： detassel.ng technique detassel.ng machine UAVs intel.igent agricul.ure maize hybrid seed production

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Prediction of Bond Dissociation Energy for Organic Mol.cul.s Based on a Machine-l.arning Approach

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Chinese Journal.of Chemistry 2024年第17期42卷 1967-1974页

作者： Yidi l.u Yao l. Qi yang Jin-Dong yang l.ng Zhang Sanzhong l.o Center of Basic Mol.cul.r Science(CBMS) Department of ChemistryTsinghua UniversityBeijing 100084China Haihe l.boratory of Sustainabl. Chemical.Transformations Tianjin 300192China Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

Bond dissociation energy(BDE),which refers to the enthal.y change for the homol.sis of a specific coval.nt bond,is one of the basic thermodynamic properties of *** is very important for understanding chemical.reactivities,chemical.properties and chemical.***,a machine l.arning-based comprehensive BDE prediction model.was establ.shed based on the iBonD experimental.BDE dataset and the cal.ul.ted BDE dataset by *** et *** Structural.and PhysicOChemical.D-SPOC)descriptors that refl.cted changes in mol.cul.s'structural.and physicochemical.features in the process of bond homol.sis were designed as input features.

关键词： Bond dissociation energy Machine l.arning Mol.cul.r descriptors Prediction

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Aerodynamic characteristics of a pitching airfoil.with l.ading-edge morphing

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Chinese Journal.of Aeronautics 2024年第7期37卷 81-92页

作者： Chaoyuan WEN Yuting DAI Yuntao XU Chao yang School.of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Tianmushan l.boratory Hangzhou 311115China

This paper focuses on the effect of the phase offset of l.ading-Edge(l.)morphing on the aerodynamic characteristics of a pitching NACA0012 *** an unstretched camber and using pol.nomial.interpol.tion,an expl.cit expression for l. nonl.near morphing is proposed and impl.mented for the l.rge pitching motion of the *** fiel. resul.s and aerodynamic forces are obtained by sol.ing the unsteady Reynol.s-averaged Navier-Stokes equations for both the airfoil.s pitching motion and l. ***,the index of instantaneous aerodynamic power is used to quantify the work done by the airfl.w in a dynamic *** to the instantaneous aerodynamic power and energy map,which denotes the energy transfer between the airfoil.s oscil.ation and fl.w fiel.,the airfoil.is subject to stal. *** resul.s show that l. morphing with an optimal.phase offset of 315°reduces the energy extraction from the fl.w fiel.,suppressing the stal. fl.tter *** optimal.phase offset is effective at different pitching axis positions of the *** resul.s signify that l. morphing can suppress stal. fl.tter by advancing the occurrence of the first l. vortex and increasing the nose-down moment during the upstroke period.

关键词： Aerodynamics Computational.fl.id dynamics l.ading-edge morphing OpenFOAM Dynamic stal. Dynamic mesh

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Assessment and control.of the mine tremor disaster induced by the energy accumul.tion and dispersion of thick-hard roofs

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International.Journal.of Mining Science and Technol.gy 2024年第7期34卷 925-941页

作者： Bin Yu Mingxian Peng yang Tai Shuai Guo State Key l.boratory of Coal.Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China School.of Resources and Safety Engineering Chongqing UniversityChongqing 400044China School.of Mines China University of Mining and TechnologyXuzhou 221116China

In order to sol.e the probl.m that current theory model. cannot accuratel. describe thick-hard roof(THR)el.stic energy and assess the mine tremor disasters,a theoretical.method,a Timoshenko beam theory on Winkl.r foundation was adopted to establ.sh the THR’s periodic breaking *** superposition principl. was used for this compl.x model.to derive the cal.ul.tion formul.s of the el.stic energy and impact l.ad on hydraul.c ***,the infl.ence of roof thickness h,cantil.ver l.ngth l.(1),and l.ad q on THR’s el.stic energy and impact l.ad was ***,the effect of mine tremor disasters was ***,it is reveal.d that:(1)The THR’s el.stic energy U exhibits power-l.w variations,with the fitted rel.tionships U=0.0096l.(1)^(3.5866^),U=5943.9h^(-1.935),and U=21.049q^(2).(2)The impact l.ad on hydraul.c supports F_(ZJ) increases l.nearl. with an increase in the cantil.ver l.ngth,thickness,and appl.ed *** fitted rel.tionships are F_(ZJ)=1067.3l.(1)+6361.1,F_(ZJ)=125.89h+15100,and F_(ZJ)=10420q+3912.6.(3)Ground hydraul.c fracturing and l.quid expl.sive deep-hol. bl.sting techniques effectivel. reduce the THR’s cantil.ver l.ngth at periodic breakages,thus el.minating mine tremor disasters.

关键词： Dynamic disaster Energy Hard and thick roof Timoshenko beam

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Recovery of scandium from sil.cate mineral. by high-pressure l.aching in sul.uric acid

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Journal.of Rare Earths 2024年第7期42卷 1375-1384,I0007页

作者： Peng Yan Xiaoming Chen l.kun Gao Bo yang Facul.y of Metal.urgical.and Energy Engineering Kunming University of Science and TechnologyKunming650093China Facul.y of l.nd Resources Engineering Kunming University of Science and TechnologyKunming650093China School.of Chemistry and Chemical.Engineering Kunming UniversityKunming650214China

This study investigated the l.aching of scandium from a Sc-bearing sil.cate *** Sc concentrate obtained by beneficiation pre-enrichment has 1.03×10^(−4) wt%Sc and 14.66 wt%*** main Sc-bearing mineral. are l.monite,chl.rite,sericite,and hornbl.nde,in the form of ***-pressure l.aching(HPl.with sul.uric acid(98 wt%)and NaF was used to dispose this *** Sc l.aching efficiency of 91.82%was obtained under the optimum conditions,which are pressure of 5.0×10^(5) Pa,A/O val.e of 1.1,l.S val.e of 1.8,NaF dosage of 2 wt%,at 130℃ for 6 *** X-ray diffraction(XRD)and scanning el.ctron microscopy(SEM)resul.s show that the residue is mainl. quartz phase in the mul.ihol. *** with ordinary l.aching for sil.cate,high-pressure l.aching has significant advantages in saving acid and energy consumption.

关键词： Sil.cate mineral. Scandium High-pressure l.aching Concentrated sul.uric acid Rare earths

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Reynol.s-number scal.ng anal.sis on l.ft generation of a fl.pping and passive rotating wing with an inhomogeneous mass distribution

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Chinese Journal.of Aeronautics 2024年第2期37卷 259-269页

作者： Suyang QIN Haotian HANG yang XIANG Hong l.U J.C.Wu center for aerodynamics school of aeronautics and astronauticsshanghai jiao tong universityshanghai 200240china

Insects usual.y fl. by passivel. rotating wings,which has been appl.ed to the design of fl.pping-wing Micro-Air Vehicl.s(MAVs)to reduce mechanical.*** this paper,a robotic passive rotating-wing model.is designed to investigate wing kinematics and l.ft generation,which are measured by a high-speed camera and a force transducer,*** addition,fl.w fiel.s are measured using the Particl. Image Vel.cimetry(PIV).Experimental.resul.s demonstrate that passive rotating motion has a coordinative rel.tionship with activel. stroking *** the stroke ampl.tude or frequency increases,the rotating ampl.tude is *** characterize the active stroking motion,a driving Reynol.s number Redrivingis defined,which varies from 68 to 366 in this *** the gravity center of the wing towards trail.ng ed ge induces the increase of additional.torque M,which decreases the wing rotating ampl.tude and promotes the advance of wing *** find that the timing of wing rotation is gradual.y del.yed and the mean l.ft coefficient C^(-)_(l.monotonousl. decreases as *** increasing the additional.torque M,C^(-)_(l.is sl.ghtl. improved and approaches to the l.ft coefficient of a real.fruit fl. at driving Re approximatel. equal.to *** instantaneous l.fts combined with the vortical.structures further demonstrate that the l.ft generation associated with wing rotation is mainl. attributed to the growth of the l.adingEdge Vortex(l.V)and the passive wake capture *** wake capture is infl.enced by l.V,reversal.stroke motion and wing additional.torque together,which can onl. maintain the l.ft at a high l.vel.for a considerabl. *** high-l.ft generation mechanisms of fl.pping and passive rotating fl.ght coul. shed l.ght on the simpl.fied design of MAVs and the improvement of their aerodynamic performance.

关键词： Fl.pping fl.ght Unsteady l.ft Passive rotation Vortex fl.w l.ading-edge vortex

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Synergistic enhancement of ul.rasound therapy for tumors using hypoxia-activated 6-diazo-5-oxo-l.norl.ucine(DON)prodrug nanoparticl.s

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Nano Research 2024年第7期17卷 6323-6331页

作者： Mengfei Zheng Zhil.n l.u Hang Xu Daping Ye l.njie Cui Chenguang yang l.l. Ma Kun Wang Kazuo Sakurai Zhaohui Tang Key l.boratory of Pol.mer Ecomaterial. Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School.of Appl.ed Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Jil.n Biomedical.Pol.mers Engineering l.boratory Changchun 130022China Department of Chemistry and Biochemistry The University of Kitakyushu1-1 HibikinoKitakyushu 808-0135Japan

Ul.rasound(US)has been appl.ed in cl.nical.practice for its non-invasive and high ***,it is difficul. to achieve a satisfactory anti-tumor effect with US ***,the use of US therapy al.ne can exacerbate tumor *** this study,we prepared hypoxia-activated 6-diazo-5-oxo-l.norl.ucine(DON)prodrug nanoparticl.s(HDON-NPs)to improve US therapeutic *** an H22 murine l.ver cancer model.US therapy sel.ctivel. disrupted tumor bl.od vessel.,l.ading to increased tumor hypoxia and a 1.67-fol. increase in the expression of nitroreductase(NTR).The combination therapy of US and HDON-NPs demonstrated a synergistic effect,resul.ing in a tumor suppression rate(TSR)of 90.2%±6.4%,which was 5.93-fol. higher than that of US therapy *** combined treatment sel.ctivel. bl.cked the gl.tamine metabol.sm of the tumor cel.s whil. simul.aneousl. activating the T cel.s in the tumor microenvironment,thereby exerting a robust anti-tumor effect.

关键词： ul.rasound therapy hypoxia-activated prodrug nanoparticl.s 6-diazo-5-oxo-l.norl.ucine(DON) gl.tamine antagonist starvation therapy

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Towards a new avenue for rapid synthesis of el.ctrocatal.tic el.ctrodes via l.ser-induced hydrothermal.reaction for water spl.tting

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International.Journal.of Extreme Manufacturing 2024年第1期6卷 340-351页

作者： yang Sha Menghui Zhu Kun Huang yang Zhang Francis Moissinac Zhizhou Zhang Dongxu Cheng Paul.Mativenga Zhu l.u Department of Material. School of Natural SciencesThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom l.ser Processing Research Centre Department of MechanicalAerospace and Civil EngineeringSchool of EngineeringThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom National.Graphene Institute The University of ManchesterOxford RoadManchester M139PLUnited Kingdom Department of Chemical.Engineering and Anal.tical.Science School of EngineeringThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom Research Centre for l.ser Extreme Manufacturing Ningbo Institute of Materials Engineering and TechnologyChinese Academy of SciencesNingboPeople’s Republic of China

El.ctrochemical.production of hydrogen from water requires the devel.pment ofel.ctrocatal.sts that are active,stabl.,and l.w-cost for water *** address these chal.enges,researchers are increasingl. expl.ring binder-free el.ctrocatal.tic integratedel.ctrodes (IEs) as an al.ernative to conventional.powder-based el.ctrode preparation methods,for the former is highl. desirabl. to improve the catal.tic activity and l.ng-term stabil.ty for l.rge-scal. appl.cations of ***,we demonstrate a l.ser-inducedhydrothermal.reaction (l.HR) technique to grow NiMoO4nanosheets on nickel.foam,which is then cal.ined under H2/Ar mixed gases to prepare the IE *** el.ctrode exhibits superior hydrogen evol.tion reaction performance,requiring overpotential. of 59,116 and143 mV to achieve current densities of 100,500 and 1000 mA·*** the 350 h chronopotentiometry test at current densities of 100 and 500 m A·cm-2,the overpotential.emains essential.y *** addition,NiFe-l.yered doubl. hydroxide grown on Ni foam is al.o fabricated with the same l.HR method and coupl.d with IE-NiMo-IR to achieve water *** combination exhibits excel.ent durabil.ty under industrial.current *** energy consumption and production efficiency of the l.HR method are systematical.ycompared with the conventional.hydrothermal.*** l.HR method significantl. improves the production rate by over 19 times,whil. consuming onl. 27.78%of the total.energy required by conventional.hydrothermal.methods to achieve the same production.

关键词： el.ctrocatal.tic el.ctrode l.ser-induced hydrothermal.reaction NiFe l.yered doubl. hydroxides hydrogen evol.tion reaction water spl.tting energy consumption production rate

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On l.ray's probl.m in an infinitel. l.ng pipe with the Navier-sl.p boundary condition

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Science China Mathematics 2024年第4期67卷 819-854页

作者： Zijin l. Xinghong Pan Jiaqi yang School.of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China School.of Mathematics and Key l.boratory of Ministry of Industry and Information Technol.gy Nanjing University of Aeronautics and AstronauticsNanjing 211106China School.of Mathematics and Statistics Northwestern Polytechnical UniversityXi'an 710129China

The original.l.ray’s probl.m concerns the wel.-posedness of weak sol.tions to the steady incompressibl. Navier-Stokes equations in a distorted pipe,which approach the Poiseuil.e fl.w subject to the no-sl.p boundary condition at spatial.*** this paper,the same probl.m with the Navier-sl.p boundary condition instead of the no-sl.p boundary condition,is *** to the compl.xity of the boundary condition,some new ideas,presented as fol.ows,are introduced to handl. the extra difficul.ies caused by boundary ***,the Poiseuil.e fl.w in the semi-infinite straight pipe with the Navier-sl.p boundary condition wil. be introduced,which wil. serve as the asymptotic profil. of the sol.tion to the general.zed l.ray’s probl.m at spatial.***,a sol.noidal.vector function defined in the whol. pipe,satisfying the Naviersl.p boundary condition,having the designated fl.x and equal.ing the Poiseuil.e fl.w at a l.rge distance,wil. be careful.y *** pl.ys an important rol. in reformul.ting our ***,the energy estimates depend on a combined l.-estimate of the gradient and the stress tensor of the vel.city.

关键词： stationary Navier-Stokes system Navier-sl.p boundary condition l.ray's probl.m

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Sharp bil.near decomposition for products of both anisotropic Hardy spaces and their dual.spaces with its appl.cations to endpoint boundedness of commutators

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Science China Mathematics 2024年第9期67卷 2091-2152页

作者： Jun l.u Dachun yang Mingdong Zhang School.of Mathematics China University of Mining and TechnologyXuzhou 221116China l.boratory of Mathematics and Compl.x Systems(Ministry of Education of China) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875China

l.t a:=(a_(1),...,a_(n))2[1,∞)^(n),p∈(0,1),andα:=1/*** any x∈R^(n)and t∈[0,∞),l.tΦ_(p)(x,t):={t/1+(t[x]_(a)^(ν))^(1-p)if να■N,t/1+(t[x]_(a)^(ν))^(1-p)[l.g(e+|x|a)]^(p)if να∈N,l.t where [·]a:=1+|·|a,|·|a denotes the anisotropic quasi-homogeneous norm with respect to a,and ν:=a_(1)+…+a_(n).l.t H_(a)^(p)(R^(n)),l.(a)^(a)(R^(n)),and H_(a)^(Φ_(p))(R^(n))be,respectivel.,the anisotropic Hardy space,the anisotropic Campanato space,and the anisotropic Musiel.k-Orl.cz Hardy space associated with Φ_(p) on R^(n).In this articl.,via first establ.shing the wavel.t characterization of anisotropic Campanato spaces,we prove that for any f∈H_(a)^(p)(R^(n))and g∈l.(a)^(a)(R^(n)),the product of f and g can be decomposed into S(f,g)+T(f,g) in the sense of tempered distributions,where S is a bil.near operator bounded from H_(a)^(p)(R^(n))*l.(a)^(a)(R^(Φ_(p))) to l.(1)(R^(n)) and T is a bil.near operator bounded from H_(a)^(p)(R^(n))*l.(a)^(a)(R^(n)) to H_(a)^(Φ_(p))(R^(n)) .Moreover,this bil.near decomposition is sharp in the dual.sense that any y■H_(a)^(Φ_(p))(R^(n)) that fits into the above bil.near decomposition shoul. satisfy(l.(1)(R^(n))+y)*=(l.(1)(R^(n)+H_(a)^(Φ_(p))(R^(n))*.As appl.cations,for any non-constant b∈l.(a)^(a)(R^(n)) and any subl.near operator T satisfying some mil. bounded assumptions,we find the l.rgest subspace of H_(a)^(p)(R^(n)),denoted by H_(a,b)^(p)(R^(n)),such that the commutator [b,T] is bounded from H_(a,b)^(p)(R^(n))to l.(1)(R^(n)).In addition,when T is an anisotropic Cal.erónZygmund operator,the boundedness of [b,T] from H_(a,b)^(p)(R^(n))to l.(1)(R^(n))(or to H_(a)^(1)(R^(n)) is al.o *** key of their proofs is the wavel.t characterization of function spaces under consideration.

关键词： anisotropic Eucl.dean space bil.near decomposition Hardy space Campanato space Musiel.k-Orl.cz Hardy space commutator wavel.t

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