In this work,we have systematically investigated precipitation ofβ’-Mg3Sn phase on intrinsic stacking faults I1 and I2 in a Mg-9.8 wt%Sn alloy using aberration-corrected scanning transmission electron *** observed I...
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In this work,we have systematically investigated precipitation ofβ’-Mg3Sn phase on intrinsic stacking faults I1 and I2 in a Mg-9.8 wt%Sn alloy using aberration-corrected scanning transmission electron *** observed I1 faults are generated by the dissociation of c+a perfect dislocations and bounded by Frank partial dislocations having a Shockley *** ofβ’on I1 involves a shear of 1/3α,similar to its formation directly from theα-Mg ***β’phase often nucleates at one end of an I1 fault due to the interaction between shear strain fields ofβ’and the Shockley component of the Frank partial at that end,and subsequently grows towards the other end of the *** theβ’reaches to the other end,the Shockley partial bounding the lengthening end of theβ’reacts with the Frank partial bounding the fault,generating an a perfect dislocation that can glide away from the precipitate and the *** observed I2 faults are generated by the dissociation of a perfect dislocations and bounded by Shockley *** ofβ’on I2 does not need a shear of 1/3α,since the pre-existing I2 fault already provides an ABcA four-layer structure ofβ’.Thickening of theβ’that has already formed on the I2 involves the successive occurrence of three crystallographically equivalent shears of 1/3αon every second(0002)αplane of theα-Mg *** this thickening mechanism is similar to that of theβ’formed directly from theα-Mg matrix,an a perfect dislocation will be produced when theβ’is thickened to eight layers,and it can again glide away from the precipitate and the fault.
Aims:Alpha-galactosidase is applied in food and feed industries for hydrolysing raffinose series oligosaccharides(RO) that are the factors primarily responsible for flatulence upon ingestion of soybean-derived *** obj...
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Aims:Alpha-galactosidase is applied in food and feed industries for hydrolysing raffinose series oligosaccharides(RO) that are the factors primarily responsible for flatulence upon ingestion of soybean-derived *** objective of the current work was to develop an optimal culture medium for the production of alpha-galactosidase in solid-state fermentation(SSF) by a mutant strain Aspergillus foetidus. Methods and Results:Response surface methodology(RSM) was applied to evaluate the effects of variables,namely the concentrations of wheat bran,soybean meal,KHPO,MnSO·HO and cuSO·5HO on alpha-galactosidase production in the solid substrate.A fractional factorial design(FFD) was firstly used to isolate the main factors that affected the production of alpha-galactosidase and the central composite experimental design(ccD) was then adopted to derive a statistical model for optimizing the composition of the fermentation *** experimental results showed that the optimum fermentation medium for alpha-galactosidase production by Aspergillus foetidus ZU-G1 was composed of 8-2137 g wheat bran,1·7843 g soybean meal,0·001 g MnSO·HO and 0·001 g cuSO·5HO in 10 g dry matter fermentation medium. conclusions:After incubating 96 h in the optimum fermentation medium, alpha-galactosidase activity was predicted to be 2210·76 U g dry matter in 250 ml shake *** the present study,alpha-galactosidase activity reached 2207·19 U g dry matter. Significance and Impact of the Study:Optimization of the solid substrate was a very important measure to increase enzyme activity and realize industrial production of *** process of alpha-galactosidase production in laboratory scale may have the potential to scale-up.
Aims:Alpha-galactosidase is applied in food and feed industries for hydrolysing raffinose series oligosaccharides(RO)that are the factors primarily responsible for flatulence upon ingestion of soybean-derived *** obje...
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Aims:Alpha-galactosidase is applied in food and feed industries for hydrolysing raffinose series oligosaccharides(RO)that are the factors primarily responsible for flatulence upon ingestion of soybean-derived *** objective of the current work was to develop an optimal culture medium for the production of alpha-galactosidase in solid-state fermentation(SSF) by a mutant strain Aspergillus foetidus.,Methods and Results:Response surface methodology (RSM)was applied to evaluate the effects of variables,namely the concentrations of wheat bran, soybean meal,KHPO,MnSO·HO and cuSO·5HO on alpha-galactosidase production in the solid substrate.A fractional factorial design(FFD)was firstly used to isolate the main factors that affected the production of alpha-galactosidase and the central composite experimental design (ccD)was then adopted to derive a statistical model for optimizing the composition of the fermentation *** experimental results showed that the optimum fermentation medium for alpha-galactosidase production by Aspergillus foetidus ZU-Gl was composed of 8.2137 g wheat bran,1.7843 g soybean meal,0.001 g MnSO·HO and 0.001 g cuSO·5HO in 10g dry matter fermentation medium.,conclusions:After incubating 96 h in the optimum fermentation medium,alpha-galactosidase activity was predicted to be 2210·76 U gdry matter in 250 ml shake *** the present study,alpha-galactosidase activity reached 2207·19 U gdry matter. Significance and Impact of the Study:Optimization of the solid substrate was a very important measure to increase enzyme activity and realize industrial production of *** process of alpha-galactosidase production in laboratory scale may have the potential to scale-up.
The nontrivial band topology of chern insulator can enrich the content of its Hofstadter butterfly spectra,which is closely related to recent experiments in twisted bilayer graphene and cold atom *** investigate the H...
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The nontrivial band topology of chern insulator can enrich the content of its Hofstadter butterfly spectra,which is closely related to recent experiments in twisted bilayer graphene and cold atom *** investigate the Hofstadter spectrum for various models of chern insulators under a rational fluxφ_(0)/q,hereφ_(0)=h/e and q being an *** find the number of splitting subbands is|q-c|with c denoting the chern number of parent ***,anomalous open-orbital subbands with chern numbers q-1 and-q-1 emerge unexpectedly,which are beyond the parameter window(-q/2,q/2)of the Diophantine equation studied by Thouless-Kohmoto-Nightingale-den Nijs[***.49,405(1982)].The emergence of anomalous open orbits can be traced by analyzing the evolution of the Hofstadter spectrum,identifying as a new type of topological phase *** novel findings not only pinpoint the peculiar Hofstadter spectrum of chern insulator,but also provide routes to study exotic characteristics beyond the Landau level physics.
Part II of this paper presents a reduced-order stability region (ROSR) based method to estimate the full-order stability region (FOSR) of a large-scale power system. First, we introduce the definitions of FOSR and ROS...
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Part II of this paper presents a reduced-order stability region (ROSR) based method to estimate the full-order stability region (FOSR) of a large-scale power system. First, we introduce the definitions of FOSR and ROSR, followed by a comprehensive theory that reveals the relationships between them. Since the full-order system can be rewritten as a standard two timescale model and the reduced-order system is regarded as the slow subsystem of it, the proposed theory is derived based on the idea of singular perturbation. With rigorous mathematical proof, the properties of FOSR and ROSR are revealed. Moreover, a modified Energy Augmented Dynamic (EAD) algorithm and a constrained equidistant projection (cEP) approach are employed to estimate the ROSR and FOSR, respectively. The modified EAD algorithm and cEP form a so-called reduced-order stability region mapping (ROSRM) method. Finally, the proposed ROSRM method is applied to the IEEE 10-machine-39-bus power system, and simulation studies confirm its superiority to the traditional energy function method in terms of computational speed and reliability of results.
This paper presents an estimation of transient stability regions for large-scale power *** Part I,a Koopman operator based model reduction(KOMR)method is proposed to derive a low-order dynamical model with reasonable ...
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This paper presents an estimation of transient stability regions for large-scale power *** Part I,a Koopman operator based model reduction(KOMR)method is proposed to derive a low-order dynamical model with reasonable accuracy for transient stability analysis of large-scale power *** traditional reduction methods based on linearized models,the proposed method does not require linearization,but captures dominant modes of the original nonlinear dynamics by employing a Koopman operator defined in an infinite-dimensional observable *** with the Galerkin projection,the obtained dominant Koopman eigenvalues and modes produce a reduced-order nonlinear *** approximate the Koopman operator with sufficient accuracy,we introduce a Polynomial-based Multi-trajectory Kernel Dynamic Mode Decomposition(PMK-DMD)algorithm,which outperforms traditional DMD in various *** the end,the proposed method is applied to the IEEE 10-machine-39-bus power system and IEEE 16-machine-68-bus power system,which demonstrates that our method is significantly superior to the modal analysis method in both qualitative and quantitative aspects.
The interplay between novel topological states and superconductivity has garnered substantial interest due to its potential for topological quantum *** Josephson effect serves as a useful probe for edge superconductiv...
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The interplay between novel topological states and superconductivity has garnered substantial interest due to its potential for topological quantum *** Josephson effect serves as a useful probe for edge superconductivity in these hybrid topological *** Josephson junctions based on topological materials,supercurrents exhibit unique quantum interference patterns,including the conventional Fraunhofer oscillations,theΦ_(0)-periodic oscillation,and the 2Φ_(0)-periodic oscillation in response to the external magnetic field(Φ_(0)=h/2e is the flux quantum,h the Planck constant,and e the electron charge).These interference patterns stem from varied Andreev reflection mechanisms and the associated current density *** review seeks to comprehensively examine the theoretical and experimental advancements in understanding the quantum interference patterns of edge supercurrents in Josephson junctions based on quantum spin Hall,quantum Hall,and quantum anomalous Hall systems.
Na_(3)V_(2)(PO_(4))_(2)O_(2)F (VP) is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory (DFT) and finite element simulat...
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Na_(3)V_(2)(PO_(4))_(2)O_(2)F (VP) is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory (DFT) and finite element simulations show that incorporating SO_(4)^(2-)into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na_(3)V_(2)(PO_(4))_(1.95)(SO_(4))_(0.05)O_(2)F(VPS-1) is roughly double that of VP,leading to enhanced rate capability (80 c,75.5 mAh g^(-1)) and cycling stability (111.0 mAh g^(-1)capacity after 1000 cycles at 10 c current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPc full cell demonstrated stable cycling over 200 cycles at a high 5 c current,maintaining an average coulombic efficiency of 95.35%.
The preparation of carbon-based electromagnetic wave(EMW)absorbers possessing thin matching thickness,wide absorption bandwidth,strong absorption intensity,and low filling ratio remains a huge ***-organic frameworks(M...
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The preparation of carbon-based electromagnetic wave(EMW)absorbers possessing thin matching thickness,wide absorption bandwidth,strong absorption intensity,and low filling ratio remains a huge ***-organic frameworks(MOFs)are ideal self-sacrificing templates for the construction of carbon-based EMW *** this work,bimetallic FeMn-MOF-derived MnFe_(2)O_(4)/c/graphene composites were fabricated via a two-step route of solvothermal reaction and the following pyrolysis *** results re-veal the evolution of the microscopic morphology of carbon skeletons from loofah-like to octahedral and then to polyhedron and pomegran-ate after the adjustment of the Fe^(3+)to Mn^(2+)molar ***,at the Fe^(3+)to Mn^(2+)molar ratio of 2:1,the obtained MnFe_(2)O_(4)/c/graphene composite exhibited the highest EMW absorption ***,a minimum reflection loss of-72.7 dB and a max-imum effective absorption bandwidth of 5.1 GHz were achieved at a low filling ratio of 10wt%.In addition,the possible EMW absorp-tion mechanism of MnFe_(2)O_(4)/c/graphene composites was ***,the results of this work will contribute to the construction of broadband and efficient carbon-based EMW absorbers derived from MOFs.
The Yangchuling porphyry W-Mo deposit(YPWD),located in the Jiangnan porphyryskarn tungsten ore belt,is one of the most important and large-scale porphyry W-Mo deposits in South *** previous zircon U-Pb and molybdenite...
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The Yangchuling porphyry W-Mo deposit(YPWD),located in the Jiangnan porphyryskarn tungsten ore belt,is one of the most important and large-scale porphyry W-Mo deposits in South *** previous zircon U-Pb and molybdenite Re-Os data suggest that Yangchuling WMo ore bodies formed almost simultaneously with granodiorite and monzogranitic porphyry at~150–144 Ma,their post emplacement history remains poorly understood,making their preservation status at depth *** this paper,new zircon and apatite(U-Th)/He and apatite fission track(ZHe,AHe and AFT,respectively)data of one hornfels and five intrusive rocks from a 1000-meter borehole are ***,together with new inverse thermal history models and previous geochronological data,help elucidate the post-diagenetic exhumation history and preservation status of the Yangchuling porphyry W-Mo *** general,ZHe and AHe ages decrease gradually from the near surface downwards and have relatively little intra-sample variation,ranging from 133 to 73Ma and 67 to 25 Ma,*** four granodiorites yield similar AFT ages that range from 63 to 55 Ma with mean track lengths varying from 12.2±0.7 to 12.6±0.5μ*** history modelling indicates that the Yangchuling ore district experienced slow,monotonic cooling since the ***-depth relationships are interpreted as recording~3.7±0.8 km of cretaceous-recent exhumation in response to regional extension throughout South china thought to have been driven by subduction retreat of the Paleo-Pacific *** of estimated net exhumation and previous metallogenic depth of~4–5 km suggests that W-Mo ore bodies could still exist at depths of up to~1.3±0.8 km relative to Earth surface in the YPWD *** of the YPWD is attributed to the limited amount of regional denudation during the Late cretaceous and cenozoic.
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