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A New Unified Electro-Gravity Theory for the Electron, and the Fundamental Origin of the Fine Structure Constant and the Casimir Effect 认领
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作者 Nirod K. Das 《高能物理(英文)》 2021年第1期66-87,共22页
A rigorous model for the electron is presented by generalizing the Coulomb’s Law or Gauss’s Law of electrostatics, using a unified theory of electricity and gravity. The permittivity of the free-space is allowed to ... A rigorous model for the electron is presented by generalizing the Coulomb’s Law or Gauss’s Law of electrostatics, using a unified theory of electricity and gravity. The permittivity of the free-space is allowed to be variable, dependent on the energy density associated with the electric field at a given location, employing generalized concepts of gravity and mass/energy density. The electric field becomes a non-linear function of the source charge, where the concept of the energy density needs to be properly defined. Stable solutions are derived for a spherically symmetric, surface-charge distribution of an elementary charge. This is implemented by assuming that the gravitational field and its equivalent permittivity function is proportional to the energy density, as a simple first-order approximation, with the constant of proportionality, referred to as the Unified Electro-Gravity (UEG) constant. The stable solution with the lowest mass/energy is assumed to represent a “static” electron without any spin. Further, assuming that the mass/energy of a static electron is half of the total mass/energy of an electron including its spin contribution, the required UEG constant is estimated. More fundamentally, the lowest stable mass of a static elementary charged particle, its associated classical radius, and the UEG constant are related to each other by a dimensionless constant, independent of any specific value of the charge or mass of the particle. This dimensionless constant is numerologically found to be closely related to the fine structure constant. This possible origin of the fine structure constant is further strengthened by applying the proposed theory to successfully model the Casimir effect, from which approximately the same above relationship between the UEG constant, electron’s mass and classical radius, and the fine structure constant, emerges. 展开更多
关键词 Electron Structure Fine-Structure Constant Casimir Effect Unified Electro-Gravity Theory
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Theoretical Spectrum of Mass of the Nucleons: New Aspects of the QM 认领
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作者 Giovanni Guido 《高能物理(英文)》 2021年第1期123-143,共21页
In this paper, we show a new theoretical procedure for calculating the nucleonic mass values. We develop this procedure on the geometric representation of (u, d) quarks, these seen as golden structures of coupled quan... In this paper, we show a new theoretical procedure for calculating the nucleonic mass values. We develop this procedure on the geometric representation of (u, d) quarks, these seen as golden structures of coupled quantum oscillators (Aureum Geometric Model or AGM). Using AGM, we also build the geometric structures of nucleons (p, n), determining their structure equations and spins. Thank AGM, coherent to QCD, new aspects of the Quantum Mechanics emerge, opening to anew descriptive paradigm in Particle Physics. 展开更多
关键词 QUARK Structure Equation Geometric Structure Golden Number INTERPENETRATION Iquo GLUON PROTON NEUTRON
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On Dineutron and Deuteron Binding Energies 认领
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作者 F. C. Hoh 《现代物理(英文)》 2021年第3期161-166,共6页
The binding energy of the deuteron is estimated from the scalar strong interaction hadron theory SSI. The predicted value is 7.7% lower than the measured value. Existence of a spin 1 dineutron with a binding energy 4/... The binding energy of the deuteron is estimated from the scalar strong interaction hadron theory SSI. The predicted value is 7.7% lower than the measured value. Existence of a spin 1 dineutron with a binding energy 4/5 that of the deuteron or 1.78 MeV is predicted. This is verified by the dineutron, first observed in 2012, in <sup>16</sup>Be decay. No free dineutrons are expected to exist in nature as they can decay into deuterons. These binding energies are limited by short range strong interaction internucleon forces but consist of long range electrostatic energies from quark charges. 展开更多
关键词 Scalar Strong Interaction Hadron Theory SSI Deuteron Structure Dineutron Structure Electromagnetic Energy Deuteron Binding Energy Dineutron Binding Energy Dineutron Decay
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Effects of Teriparatide and Aerobic Exercise on Lumbar Spine Microstructure in Ovariectomized and Tail-Suspended Rats 认领
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作者 Chiaki Sato Naohisa Miyakoshi +8 位作者 Yuji Kasukawa Koji Nozaka Hiroyuki Tsuchie Itsuki Nagahata Yusuke Yuasa Kazunobu Abe Hikaru Saito Ryo Shoji Yoichi Shimada 《矫形学期刊(英文)》 2021年第1期1-11,共11页
O<span>steoporosis is an increasingly prevalent malady of the elderly that is associated with bone fragility and increased risk of fractures. Osteoporosis treatments focus on restoring bone strength and quality.... O<span>steoporosis is an increasingly prevalent malady of the elderly that is associated with bone fragility and increased risk of fractures. Osteoporosis treatments focus on restoring bone strength and quality. Teriparatide (TPTD) is </span><span>a therapeutic agent that has been shown to increase bone strength by improving the volume and connectivity of trabecular bone. Exercise is also known to have pro-osteogenic effects. Here we used a rat model of severe osteoporosis (ovariectomized and tail-suspension) to evaluate th</span><span>e effects of TPTD, exercise and a combination of TPTD and exercise on the microstructure of trabecular </span><span>bone. TPTD mono-therapy and TPTD combined with exercise treatment significantly increased bone mineral density (BMD) in the whole body</span><span>. </span><span>Micro-computed tomography analysis revealed that </span><span>a combination of exercise and TPTD treatment significantly decreased bone surface to volume and trab</span><span>ecular separation compared with those of the control and exercise groups. Node-strut analysis indicated that exercise or TPTD alone did not affect trabecular bone connectivity. However, the combination of exercise and TPTD treatment significantly decreased measures of tra</span><span>becular bone connectivity (node number) that are consistent with a transition from rod-like to plate-like of trabecular bone microstructures. The combination treatment with exercise and TPTD improved microstructure of trabecular bone in the OVX and tail-suspended rats. These results indicate that combining exercise with TPTD represents a viable means to improve cancellous bone strength in osteoporosis populations.</span> 展开更多
关键词 TERIPARATIDE Aerobic Exercise Micro Structure Cancellous Bone
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Identification of Secondary Structure of Extracellular Signal Regulated Kinase (ERK) Interacting Proteins and Their Domain: An in Silico Study 认领
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作者 Kurrey Khuleshwari Paramanik Vijay 《神经科学国际期刊(英文)》 2021年第1期67-89,共23页
ERK is involved in multiple cell signaling pathways through its interacting proteins. By </span><i><span style="font-size:12px;font-family:Verdana;">in</span></i> <i><s... ERK is involved in multiple cell signaling pathways through its interacting proteins. By </span><i><span style="font-size:12px;font-family:Verdana;">in</span></i> <i><span style="font-size:12px;font-family:Verdana;">silico</span></i><span style="font-size:12px;font-family:Verdana;"> analysis, earlier we have identified 22 putative ERK interacting proteins namely;ephrin type-B receptor 2 isoform 2 precursor (EPHB2), mitogen-activated protein kinase 1</span></span><span "="" style="font-size:10pt;"> </span><span "="" style="font-size:10pt;"><span style="font-size:12px;font-family:Verdana;">(MAPK1), interleukin-17 receptor D precursor (IL17RD), WD repeat domain containing 83 (WDR83), </span><span style="font-size:12px;font-family:Verdana;">tescalcin (Tesc), mitogen-activated protein kinase kinase kinase 4 (MAPP3K4),</span><span style="font-size:12px;font-family:Verdana;"> kinase suppressor of Ras2 (KSR2), mitogen-activated protein kinase kinase 6 (MAP3K6), UL16 binding protein 2 (ULBP2), UL16 binding protein 1 (ULBP1), dual specificity phosphatase 14 (DUSP14), dual specificity phosphatase 6 (DUSP6), hyaluronan-mediated motility receptor (RHAMM), kinase D interacting substrate of 220</span></span><span "="" style="font-size:10pt;"> </span><span "="" style="font-size:12px;font-family:Verdana;">kDa (KININS220), membrane-associated guanylate kinase (MAGI3), phosphoprotein enriched in astrocytes 15</span><span "="" style="font-size:10pt;"> </span><span "="" style="font-size:12px;font-family:Verdana;">(PEA15), typtophenyl-tRNA synthetase, cytoplasmic (WARS), dual specificity phosphatase 9 (DUSP9), mitogen-activated protein kinase kinase kinase 1</span><span "="" style="font-size:10pt;"> </span><span "="" style="font-size:12px;font-family:Verdana;">(MAP3K1), UL16 binding protein 3 (ULBP3), SLAM family member 7 isoform a precursor (SLAMMF7) and mitogen activated protein kinase kinase kinase 11 (MAP3K11) (</span><span "="" style="font-size:10pt;"><a href="file:///E:/%E5%B7%A5%E4%BD%9C%E8%AE%B0%E5%BD%95/2021/0225-wqs-%E5%B7%A 展开更多
关键词 ERK Secondary Structure Motif Scan Random Coils Alpha Helix Protein Kinases
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New Probability Distributions in Astrophysics: V. The Truncated Weibull Distribution 认领
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作者 Lorenzo Zaninetti 《天文学与天体物理学国际期刊(英文)》 2021年第1期133-149,共17页
We demonstrate that certain astrophysical distributions can be modelled with the truncated Weibull distribution, which can lead to some insights: in particular, we report the average value, the <em>r</em>t... We demonstrate that certain astrophysical distributions can be modelled with the truncated Weibull distribution, which can lead to some insights: in particular, we report the average value, the <em>r</em>th moment, the variance, the median, the mode, the generation of random numbers, and the evaluation of the two parameters with maximum likelihood estimators. The first application of the Weibull distribution is the initial mass function for stars. The magnitude version of the Weibull distribution is applied to the luminosity function for the Sloan Digital Sky Survey (SDSS) galaxies and to the photometric maximum of the 2MASS Redshift Survey (2MRS) galaxies. The truncated Weibull luminosity function allows us to model the average value of the absolute magnitude as a function of the redshift for the 2MRS galaxies. 展开更多
关键词 Stars: Normal Galaxy Groups CLUSTERS and Superclusters Large Scale Structure of the Universe COSMOLOGY
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Structural Study, Vibrational, Optical, Thermal Properties and Hirshfeld Surface Analysis of a New Iron (III) Complex: FeCl<sub>4</sub>(C<sub>5</sub>N<sub>2</sub>H<sub>6</sub>)(C<sub>5</sub>N<sub>2</sub>H<sub>5</sub>) 认领
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作者 Amal Arouri Rihab Dridi +1 位作者 Riadh Kefi Mohamed Faouzi Zid 《晶体结构理论与应用(英文)》 2021年第1期14-26,共13页
The title compound, FeCl<sub>4</sub>(C<sub>5</sub>N<sub>2</sub>H<sub>6</sub>)(C<sub>5</sub>N<sub>2</sub>H<sub>5</sub>) consists of tw... The title compound, FeCl<sub>4</sub>(C<sub>5</sub>N<sub>2</sub>H<sub>6</sub>)(C<sub>5</sub>N<sub>2</sub>H<sub>5</sub>) consists of two [(C<sub>5</sub>N<sub>2</sub>H<sub>6</sub>) (C<sub>5</sub>N<sub>2</sub>H<sub>5</sub>)]<sup>+</sup> organic cations and [FeCl<sub>4</sub>]<sup>-</sup> anion. The geometry of the iron ion is tetrahedral, formed by four chlorine atoms. The complex was characterized by single crystal X-ray diffraction, Fourier Transform Infrared spectroscopy, thermal analysis and UV-Visible spectroscopy. Hirshfeld surface analysis was also used for understanding the intermolecular interactions in the crystal packing. Single-crystal X-ray diffraction analysis indicates that this complex crystallizes in the monoclinic system, P2<sub>1</sub>/c space group with a = 7.598 (3) &#197;, b = 13.694 (4) &#197;, c = 17.105 (5) &#197;, <i>β</i><i> </i>= 97.203 (6)° V = 1765.7 (10) &#197;<sup>3</sup> and Z = 4. The [FeCl<sub>4</sub>]<sup>-</sup> anion and [(C<sub>5</sub>N<sub>2</sub>H<sub>6</sub>)(C<sub>5</sub>N<sub>2</sub>H<sub>5</sub>)]<sup>+</sup> cations are linked through three-dimensional hydrogen-bonding network consisting of N-H...Cl and π-π interactions. Hirshfeld surface analysis and the related 2D fingerprint plots reveal that the complex is dominated by N-H...Cl contacts. 展开更多
关键词 COMPLEX Crystal Structure X-Ray Analysis Optical Study Thermal Analysis Hirshfeld Surface
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A Passive Anti-icing Strategy Based on a Superhydrophobic Mesh with Extremely Low Ice Adhesion Strength 认领
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作者 Peng Wang Ziqiang Li +3 位作者 Qing Xie wei Duan Xinchun Zhang Huilong Han 《仿生工程学报:英文版》 SCIE EI CSCD 2021年第1期55-64,共10页
Although superhydrophobic materials have attracted much research interest in anti-icing,some controversy still exists.In this research,we report a cost-effective method used to verify the contribution of area fraction... Although superhydrophobic materials have attracted much research interest in anti-icing,some controversy still exists.In this research,we report a cost-effective method used to verify the contribution of area fraction to ice adhesion strength.We tried to partially-embed siliea nanopnarticles into microscale fabrics of a commercial polyamide mesh.Then,the area fraction could be determined by altering the mesh size.Generally,the ice adhesion strength decreases as the area fraction decreases.An ice adhesion strength of~1.9 kPa and a delayed freezing time of~1048 s can be obtained.We attribute the low ice adhesion strength to the combination of superhydro-phobicity and stress concentration.The superhydrophobicity prohibits the water from penetrating into the voids of the meshes,and the small actual contact area leads to stress concentration which promotes interfacial crack propagation.Moreover,our superhydrophobic mesh simultaneously exhibis a micro-nano hierarchical structure and a partally-cmbedded structure.Therefore,the as-prepared superhydrophobic mesh retained the ieephobicity after 20 icingldeicing cycles,and maintained its superhydrophobicity even afier 60 sandpaper-abrasion cycles and a 220"C thermal treatment. 展开更多
关键词 BIONIC SUPERHYDROPHOBIC ANTI-ICING mechanical robustness hierarchical structure partially-embedded structure
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A Physical Origin for Quantum Entanglement and Probabilistic Behaviors 认领
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作者 Kenneth H. Schatten 《现代物理(英文)》 2021年第1期50-58,共9页
Quantum Mechanics’ entanglement and probabilistic behaviors are viewed in the light of Quantum Field Theory’s (QFT’s) advances made during the last century. In particular, Bohm’s version (B-EPR) of the Einstein, P... Quantum Mechanics’ entanglement and probabilistic behaviors are viewed in the light of Quantum Field Theory’s (QFT’s) advances made during the last century. In particular, Bohm’s version (B-EPR) of the Einstein, Podolsky, Rosen (EPR) experiment is now viewed with the aid of QFT’s modern description of electrons. In QFT, free electrons possess a bare core surrounded by a “dressing”. The dressing consists of one or more virtual particles/fields pulled from the vacuum during the bound electron’s parturition. In QFT, a bound electron’s freedom is aided by eliminating its energy losses from bremsstrahlung. The paper develops a “Shimony” numerical model using QFT’s free electron structure with the aid of a “random vector paradigm” (RVP). The RVP simply expresses QFT’s free electron as a bare core surrounded by an EM dressing. Using this RVP, we imbue newly freed electrons with a vector-like EM spin property of 1/2. From this, the Shimony Monte Carlo computer analysis provides a detailed comparison of the B-EPR experiment as described by Bell. The entanglement property can serve to provide a way to transport shared encoded information. Overall, the electron dressing can convey random elements that may provide QM with its entanglement and probabilistic behaviors. 展开更多
关键词 Quantum Mechanics ENTANGLEMENT Probability EINSTEIN Electron ORIGIN Structure
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The Mechanical Characteristics and Experimental Study of the Stratospheric Airship 认领
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作者 Xu Ning Ping Liu Zhihong Pan 《应用数学与应用物理(英文)》 2021年第1期183-196,共14页
Stratospheric airship is a special near-space air vehicle which has lots of advantages than other traditional flying aircrafts, such as long endurance, strong survival ability, low cost, excellent resolution detector ... Stratospheric airship is a special near-space air vehicle which has lots of advantages than other traditional flying aircrafts, such as long endurance, strong survival ability, low cost, excellent resolution detector etc. In addition, the stratospheric airship can be an ideal stratospheric bearing platform. This paper firstly gave an overview describing some technical differences between the stratospheric airship and the traditional airship, including the working environment, design specifications, structure characteristics, energy system, flying modes, and so on. Some technical difficulties including the materials, power system which apply to the stratospheric airship and deformation of the huge hull, super-heating effect, and station-keeping were discussed. Furthermore, technical target, technical specifications, design concept, and overview of flying tested about two stratospheric demonstration airships which were representative achievements of the research on the stratospheric airship in China were introduced. Finally, the predictions about the progress and direction of development were discussed. 展开更多
关键词 Stratospheric Airship Demonstration Test Membrane Structure
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Dust Retention Ability of Plants as a Factor Improving Environment Air 认领
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作者 Tazhimamat Erkebaev Kursantbek Attokurov +6 位作者 Absamat Sattarov Minavar Shaimkulova Nurgazy Orozaliev Tashbolot Erkebaev Elida Topchubaeva Nurgul Kaparova Zhypargul Abdullaeva 《美国植物学期刊(英文)》 2021年第2期187-198,共12页
It is well known that air in industrial cities contains a significant amount of dust particles, smoke, and toxic gases. The increased number of vehicles has a direct impact on air quality resulting in the emission of ... It is well known that air in industrial cities contains a significant amount of dust particles, smoke, and toxic gases. The increased number of vehicles has a direct impact on air quality resulting in the emission of exhaust gases, and the increase of dust concentration in air. In this article, we are describing the dust retention ability of plants depending on their leaf structure. Plant species were classified into three groups according to their dust-holding capacities. Dust retaining ability of plant species in conditions of high, average and low dust conditions described. 展开更多
关键词 Dust Retention Leaf Morphological Structure Rough Leaf Surface Smooth Leaf Surface High Dust Retention Capacity Average Dust Retention Low Dust Retention Capacity
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Buckling analysis of planar linear uniform deployable structures consisting of scissor-like element in space under compression 认领
12
作者 LI Bo WANG SanMin TAN U-Xuan 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2021年第3期493-507,共15页
This paper comprehensively investigates the buckling load and the stability of a planar linear array deployable structure composed of scissor-like element(SLE)under compression.At present,the researches on deployable ... This paper comprehensively investigates the buckling load and the stability of a planar linear array deployable structure composed of scissor-like element(SLE)under compression.At present,the researches on deployable structure are mainly focused on configuration design and dynamics characteristics of the mechanisms,but less on structural instability.In fact,when the external load exceeds the structural critical load value,the deployable structure will be permanently deformed or even collapse directly and no longer have any bearing capacity.To address this issue,a new stability model is derived using linear elastic analysis method and substructure method to evaluate the buckling characteristics of the deployable structure with n SLEs when it is carried out in space,which can accurately obtain the structural instability load and can be used quantitatively to optimize the structure for making it have the most stable configuration.In addition,the effects of the number of elements,the length,material properties and flexibility of the bar,and the deployment degree on the buckling of the scissor deployable structure are investigated,and the results of the theoretical analysis are compared with simulation and analytical results,respectively,confirming that the proposed stability model not only is able to effectively predict the structural instability load but also determine which part of the deployable structure is unstable.It can be concluded that the stability of the deployable structure gradually decreases with the increase of the number of elements or the bar flexibility.In the calculation process,the critical load of each sub-element should be considered,and the minimum value of the critical loads of all subunits can be regarded as the instability load of the whole structure. 展开更多
关键词 deployable structure stability analysis buckling load sub structure linear array simulation
Implications of Nitrogen Doping on Geometrical and Electronic Structure of the Fullerene Dimers 认领
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作者 Yin Su Zuo-Chang Chen +4 位作者 Han-Rui Tian Yun-Yan Xu Qianyan Zhang Su-Yuan Xie Lan-Sun Zheng 《中国化学:英文版》 SCIE CAS CSCD 2021年第1期93-98,共6页
Because of its unsaturated bonds,C60 is susceptible to polymerize into dimers.The implications of nitrogen doping on the geometrical and electronic structure of C60 dimers have been ambiguous for years.A quarter... Because of its unsaturated bonds,C60 is susceptible to polymerize into dimers.The implications of nitrogen doping on the geometrical and electronic structure of C60 dimers have been ambiguous for years.A quarter-century after the discovery of azafullerene dimer(C59N)2,we reported its single crystallographic structure in 2019. 展开更多
关键词 FULLERENES DIMERS Structure elucidation Density functional calculations Crystallographic structure
Lithospheric thermal and compositional structure of South China jointly inverted from multiple geophysical observations 认领
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作者 Bin SHAN Wanli ZHOU Yang XIAO 《中国科学:地球科学英文版》 SCIE EI CSCD 2021年第1期148-160,共13页
The detailed lithospheric structure of South China is the basis for the understanding of tectonic processes of eastern China.Specifically,two essential issues in the study of lithospheric structure are the thermal and... The detailed lithospheric structure of South China is the basis for the understanding of tectonic processes of eastern China.Specifically,two essential issues in the study of lithospheric structure are the thermal and compositional structures,which are usually derived from either geophysical or geochemical observations.However,inversions from single geophysical or geochemical datasets have certain limitations,making it necessary to develop joint inversions of geophysical,geochemical and petrological datasets.In this paper,through thermodynamic simulation and probabilistic inversion,we inverted multiple datasets including topography,geoid height,surface heat flow and surface wave dispersion curves for the 3D lithospheric thermal and compositional structure of South China.The results reveal a thin(<100 km)and flat LAB beneath the South China Fold System Block and the lower Yangtze Craton.Also,we found that the lithospheric mantle is primarily composed of saturated peridotite,indicating that the ancient refractory lithospheric mantle has been replaced by new materials.The dominant dynamic mechanism for lithospheric thinning in eastern South China may be the flat subduction of ancient Pacific slab,while thermal erosion may have also played a significant role.In contrast,the LAB depth beneath the Sichuan Basin is much thicker(>200 km),suggesting that the thick and cold craton lithospheric roots are retained.There may exist a discontinuous interface beneath the Sichuan Basin,with the saturated lower layer thicker than the refractory upper layer.As a result,the lithospheric mantle of the Sichuan Basin and surrounding regions is mainly composed of saturated and transitional peridotite. 展开更多
关键词 South China Lithospheric thermal structure Lithospheric compositional structure Thermodynamic inversion
Synthesis, Characterization and Biological Activities of Binuclear Metal Complexes of 2-Benzoylpyridine and Phenyl(Pyridin-2-yl) Methanediol Derived from 1-Phenyl-1-(Pyridin-2-yl)-N-(Pyrimidin-2-yl) Methanimine Dihydrate Schiff Base 认领
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作者 Francis A. Ngounoue Kamga Evans Ngandung Mainsah +1 位作者 Maurice Kuate Peter T. Ndifon 《无机化学期刊(英文)》 2021年第1期20-42,共23页
The Schiff base, 1-phenyl-1-(pyridin-2-yl)-N-(pyrimidin-2-yl)methanimine dihydrate (L<sub>1</sub>) has been synthesized by the condensation reaction between 2-aminopyrimidine and 2-benzoylpyridine and char... The Schiff base, 1-phenyl-1-(pyridin-2-yl)-N-(pyrimidin-2-yl)methanimine dihydrate (L<sub>1</sub>) has been synthesized by the condensation reaction between 2-aminopyrimidine and 2-benzoylpyridine and characterized using <sup>13</sup>C-NMR, <sup>1</sup>H-NMR, microanalysis, FT-IR, DEPT-135, HSQC, HMBC, COZY, NOESY. The reaction of 1-phenyl-1-(pyridin-2-yl)-N-(pyrimidin-2-yl)methanimine dihydrate (L<sub>1</sub>) with salts of V(IV), Co(II) and Cu(II), however, resulted in the hydrolysis of L<sub>1</sub> to give binuclear metal complexes of 2-benzoylpyridine (L<sub>2</sub>) and phenyl(pyridin-2-yl)methanediol (L<sub>3</sub>) which were characterized using UV-visible spectroscopy, and TGA. The single crystal x-ray structure determined for the Copper(II) complex revealed that we obtained a compound previously obtained using a different method of synthesis. The Schiff base ligand (L<sub>1</sub>) is soluble in methanol, ethanol, DMSO, acetone and DMF. Microanalysis and Spectroscopic studies indicated that binuclear metal complexes were obtained by the coordination of metal ion to 2-benzoylpyridine (L<sub>2</sub>) and phenyl(pyridin-2-yl)methanediol (L<sub>3</sub>) from the hydrolysis of L<sub>1</sub>. Spectroscopic and elemental analysis reveal the formation of square pyramidal complexes of Co(II) and Cu(II) and a square planar complex of V(IV). <i>In vitro</i> antibacterial and antifungal activity against three bacterial strains (<i>Escherichia coli, Klebsiella pneumoniae</i> and <i>Staphylococcus aureus</i>) and three fungal stains (<i>Candida albicans, Candida glabrata and Candida parapsilosis</i>) showed moderate biological activity. Antioxidant studies reveal that only the binuclear Co(II) and oxovanadium(II) complexes are potent to eliminate free radicals. 展开更多
关键词 Binuclear Complexes Schiff Base 2-Benzoylpyridine Crystal Structure Antimicrobial Activity Antioxidant Activity
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Effects of Particle Stacking Angle on Heat Transfer Characteristics of Particles Close to the Wall 认领
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作者 Kai Zhang Peng Sun +5 位作者 Bin Zheng Jiguo Xu Youtang Wang Zhenling Wang Quanzhen Wang Yongqi Liu 《世界工程和技术(英文)》 2021年第1期83-91,共9页
The primary energy demand increases, but a large amount of waste heat resources w</span><span style="font-family:Verdana;">ere </span><span style="font-family:Verdana;">... The primary energy demand increases, but a large amount of waste heat resources w</span><span style="font-family:Verdana;">ere </span><span style="font-family:Verdana;">not effectively used. To explore the influence of particle stacking structure on waste heat recovery process, CFD method was used to simulate. An unsteady heat transfer model of two particles was established, effect of particle stacking angle on heat transfer characteristics of the particles close to the wall under different initial temperature conditions was studied. Results show that: higher initial temperature, resulting in increased heat transfer time, the larger particle stacking angle causes the shortening of heat transfer time. When initial temperature is 1073</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">K, the average wall heat flux shows a trend of rapid decline first and then a slow one. At the same moment, the larger stacking angle causes smaller particle average temperature. The change of particle stacking angle shows a greater impact on the temperature of the particles close to adiabatic wall. The increase in the stacking angle resulting in better heat transfer characteristics between particles. 展开更多
关键词 Stacking Structure Waste Heat Recovery Stacking Angle Particles Close to the Wall Numerical Simulation
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Regeneration Characteristics and Spatial Pattern of <i>Platycladus orientalis</i>in Mount Tai, China 认领
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作者 Wenhui Li Xiyue Zhao +2 位作者 Jinli Bian Ruiqiang Liu Ruiqiang Ni 《生态学期刊(英文)》 2021年第3期276-286,共11页
<em>Platycladus orientalis</em> is one of the main tree species in Mount Tai, and its sustainable development is of great significance to the protection and development of the forest ecological environment... <em>Platycladus orientalis</em> is one of the main tree species in Mount Tai, and its sustainable development is of great significance to the protection and development of the forest ecological environment of Mount Tai. In this study, a representative sample plot of <em>Platycladus orientalis</em> with a size of 30 m * 20 m was selected on Mount Tai. The growth and distribution of the parent trees and seedlings of <em>Platycladus orientalis</em> were investigated in the sample plots. The results showed that both the mother cypress trees and seedlings inside the plot present an aggregated distribution pattern within a certain scale, which conforms to the distribution of most natural communities;and the mother cypress can promote seedlings within a certain scale. Although <em>Platycladus orientalis</em> has good natural regeneration ability, it is difficult to succeed in understory regeneration solely relying on natural fertility, and it is not conducive to the long-term stable development of forest stands. Therefore, the thinning of <em>Platycladus orientalis</em> and the adjustment of the forest stand structure and artificial promotion of natural regeneration can not only reduce operating costs, but also conform to the idea of forest near-natural management and maintain sustainable forest development. 展开更多
关键词 Platycladus orientalis Understory Regeneration Point Pattern Analysis Community Structure Intraspecific Relationship
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Two Low-temperature Phase Transition Compounds Based on Quinuclidine Derivatives with Fluorescence 认领
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作者 李俊毅 陈祥 +2 位作者 佟亮 邓思雨 陈立庄 《结构化学》 SCIE CAS CSCD 2021年第2期149-159,145,共12页
Two phase transition materials[iPrQ]2MnBr4(1,iPrQ=N-isopropyl-quinuclidinium)and[iPrQ]2MnCl4(2)were synthesized and characterized.Dielectric measurements and differential scanning calorimetry showed that the two... Two phase transition materials[iPrQ]2MnBr4(1,iPrQ=N-isopropyl-quinuclidinium)and[iPrQ]2MnCl4(2)were synthesized and characterized.Dielectric measurements and differential scanning calorimetry showed that the two compounds underwent reversible phase transitions at ca.–47 and–37℃,respectively.Variable-temperature single-crystal X-ray diffraction suggested that the two compounds underwent the same phase transitions from space group C2/c to Cc but at different temperature.The variable crystal structures indicated that the structural phase transitions of the compound were ascribed to the torsional movement of quinuclidine ring and the disappearance of the c-slide plane.The second harmonic generation(SHG)response further proved this structural phase transition.Fluorescence tests showed that the two compounds have strong fluorescence.The strong variations in dielectric anomalies make compounds 1 and 2 suitable for promising switchable dielectric materials. 展开更多
关键词 quinuclidine derivatives fluorescent compounds crystal structure second harmonic generation(SHG) permittivity properties
基于欧根缎力学性能的服装设计 认领
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作者 韩旭辉 《上海纺织科技》 北大核心 2021年第3期15-18,共4页
欧根缎是近年来流行的一种轻薄型丝织物,其织物风格独特。对欧根缎的拉伸、折皱弹性、悬垂性、硬挺度、纰裂等力学性能进行测试,并与真丝缎、绡、塔夫绸、富春纺4种丝织物进行比较分析,得出真丝欧根缎不同于常见丝绸织物,具有弹性差、... 欧根缎是近年来流行的一种轻薄型丝织物,其织物风格独特。对欧根缎的拉伸、折皱弹性、悬垂性、硬挺度、纰裂等力学性能进行测试,并与真丝缎、绡、塔夫绸、富春纺4种丝织物进行比较分析,得出真丝欧根缎不同于常见丝绸织物,具有弹性差、悬垂性差、硬挺、易纰裂等特点,并进行了服装款式设计、结构设计、工艺设计和成品制作。力学试验摆脱了主观经验的不确定性,为根据面料性能科学进行服装全流程设计提供了参考依据。 展开更多
关键词 真丝织物 欧根缎 机械性能 服装设计 结构 工艺 织物风格
Theoretical Studies on the Electronic Properties of R2M14B(R=Lanthanides from La to Lu;M=Mn,Fe,Co,and Ni) 认领
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作者 饶霜 林晨升 +1 位作者 何长振 柴国良 《结构化学》 SCIE CAS CSCD 2021年第2期160-168,145,共10页
To search for an alternative for Nd2Fe14B,we have studied the electronic structures of R2M14B compounds,where R stands for rare-earth element and M for Mn,Fe,Co and Ni.By density functional theory(DFT),we ... To search for an alternative for Nd2Fe14B,we have studied the electronic structures of R2M14B compounds,where R stands for rare-earth element and M for Mn,Fe,Co and Ni.By density functional theory(DFT),we discuss the atomic coordination environment and partial density of states(PDOS)in detail,with the emphasis on the interaction between the six kinds of M sites and the R atoms.We systemically calculated the electronic structures of sixty R2M14B compounds to provide systematic and reliable results for explaining the origination of magnetism,which is important for further development of Nd2Fe14B based magnet materials. 展开更多
关键词 partial density of states Nd2Fe14B density functional theory electronic structure
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