Point cloud completion aims to infer complete point clouds based on partial 3D point cloud *** previous methods apply coarseto-fine strategy networks for generating complete point ***,such methods are not only relativ...
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Point cloud completion aims to infer complete point clouds based on partial 3D point cloud *** previous methods apply coarseto-fine strategy networks for generating complete point ***,such methods are not only relatively time-consuming but also cannot provide representative complete shape features based on partial *** this paper,a novel feature alignment fast point cloud completion network(FACNet)is proposed to directly and efficiently generate the detailed shapes of *** aligns high-dimensional feature distributions of both partial and complete point clouds to maintain global information about the complete *** its decoding process,the local features from the partial point cloud are incorporated along with the maintained global information to ensure complete and time-saving generation of the complete point *** results show that FACNet outperforms the state-of-theart on PCN,Completion3D,and MVP datasets,and achieves competitive performance on ShapeNet-55 and KITTI ***,FACNet and a simplified version,FACNet-slight,achieve a significant speedup of 3–10 times over other state-of-the-art methods.
The constant amplitude loading fatigue tests were carried out on the 6061/7075 aluminum alloy TIG fillet welded lap specimens in this study,and the weld seam cross-section hardness was *** experimental results show th...
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The constant amplitude loading fatigue tests were carried out on the 6061/7075 aluminum alloy TIG fillet welded lap specimens in this study,and the weld seam cross-section hardness was *** experimental results show that most specimens mainly failed at the 7075 side weld toes even though the base material tensile strength of 7075 is higher than that of *** maximum stress-strain concentration in the two finite element models is located at the 7075 side weld toe,which is basically consistent with the actual fracture *** weld zone on the 7075 side experiences severe material softening,with a large ***,the Vickers hardness value on the 6061 side negligibly changes and fluctuates around 70 *** obvious defects are found on the fatigue fracture,but a large number of secondary cracks *** germinate from the weld toe and propagate in the direction of the plate *** reinforcement has a serious impact on fatigue *** life will decrease exponentially as the weld reinforcement increases under low *** is found that the notch stress method can give a better fatigue life prediction for TIG weldments,and the errors of the predicted results are within the range of two factors,while the prediction accuracy decreases under low *** equivalent structural stress method can also be used for fatigue life prediction of TIG weldments,but the errors of prediction results are within the range of three factors,and the accuracy decreases under high stress.
Improving and optimizing the target properties of ceramics via the high entropy strategy has attracted significant *** earth niobate is a potential thermal barrier coating(TBCs)material,but its poor high-temperature p...
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Improving and optimizing the target properties of ceramics via the high entropy strategy has attracted significant *** earth niobate is a potential thermal barrier coating(TBCs)material,but its poor high-temperature phase stability limits its further *** this work,four sets of TBCs high-entropy ceramics,(Sm1/5Dy1/5Ho1/5Er1/5Yb1/5)(Nb1/2Ta1/2)O4(5NbTa),(Sm1/6Dy1/6Ho1/6Er1/6Yb1/6Lu1/6)(Nb1/2Ta1/2)O4(6NbTa),(Sm1/7Gd1/7Dy1/7Ho1/7Er1/7Yb1/7Lu1/7)(Nb1/2Ta1/2)O4(7NbTa),(Sm1/8Gd1/8Dy1/8 Ho1/8Er1/8Tm1/8Yb1/8Lu1/8)(Nb1/2Ta1/2)O4(8NbTa)are synthesized using a solid-state reaction method at 1650 ℃ for 6 ***,the X-ray diffractometer(XRD)patterns display that the samples are all single-phase solid solution structures(space group C2/c).Differential scanning calorimetry(DSC)and the high-temperature XRD of 8NbTa cross-check that the addition of Ta element in 8HERN increases the phase transition temperature above 1400 ℃,which can be attributed to that the Ta/Nb co-doping at B site introduces the fluctuation of the bond strength of Ta-O and ***,compared to high-entropy rare-earth niobates,the introduction of Ta atoms at B site substantially reduce thermal conductivity(re-duced by 44%,800 ℃)with the seven components high entropy ceramic as an *** low thermal conductivity means strong phonon scattering,which may originate from the softening acoustic mode and flattened phonon dispersion in 5-8 principal element high entropy rare earth niobium tantalates(5-8NbTa)revealed by the first-principles ***,the Ta/Nb co-doping in 5-8NbTa systems can further optimize the insulation performance of oxygen *** oxygen-ion conductivity of 8NbTa(3.31 × 10-6 S cm-1,900 ℃)is about 5 times lower than that of 8HERN(15.8 × 10-6 S cm-1,900 ℃)because of the sluggish diffusion effect,providing better oxygen barrier capacity in 5-8NbTa systems to inhibit the overgrowth of the thermal growth oxide(TGO)of *** addition,influenced by lattice dis-
Graphitic carbon nitride(g-C3N4) is a promising material for photocatalytic hydrogen production owing to its tunable band structure and high charge carrier density, however, it displays a high carrier recombination ...
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Graphitic carbon nitride(g-C3N4) is a promising material for photocatalytic hydrogen production owing to its tunable band structure and high charge carrier density, however, it displays a high carrier recombination *** engineering can solve this problem by providing active sites within g-C3N4to accelerate the separation of photogenerated electrons and holes and enhance its solar light absorption. Previous studies have implied that there exists a defect concentration threshold for obtaining the maximum photocatalytic hydrogen production performance, but the underlying mechanism remains unclear. In this study, the relationship between charge carrier density and exciton recombination was investigated to address this issue. A series of g-C3N4photocatalysts with different tri-coordinate nitrogen(N3C) vacancy concentrations were synthesized using in-situ coprecipitation polymerization. The catalytic performance is related to the vacancy concentration, higher vacancy concentration will lead to higher carrier separation efficiency and carrier density of g-C3N4, as well as better photocatalytic hydrogen production performance. However, when excessive vacancies act as recombination centers, the charge carrier recombination rate is increased, which will also adversely affect the photocatalytic hydrogen production performance.
The performances of magnesium alloys remain insufficient to further enhance the application potential of ultralight magnesium *** this work,a Mg-8Li-3Y-2Zn alloy was prepared through vacuum melting and subsequent heat ...
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The performances of magnesium alloys remain insufficient to further enhance the application potential of ultralight magnesium *** this work,a Mg-8Li-3Y-2Zn alloy was prepared through vacuum melting and subsequent heat treatment at 300,450,and 500°*** material properties of the resulting samples were assessed through microstructural observation,tensile testing,electrical conductivity measurements,and electromagnetic shielding effectiveness(EMI-SE)*** influence of the Mg-8Li-3Y-2Zn alloy microstructure on its mechanical and electromagnetic shielding properties in different states was *** was found that the as-cast alloy containsα-Mg,β-Li,Mg_(3)Zn_(3)Y_(2),and Mg_(12)ZnY *** heat treatment at 500℃(HT500),the blockα-Mg phase transformedfine needle-shapes,its tensile strength increased to 263.7 MPa,and its elongation reached 45.3%.The mechanical properties of the alloy were significantly improved by the synergistic effects imparted by the needle-shapedα-Mg phase,solid solution strengthening,and precipitation *** addition of Y and Zn improved the EMI-SE of Mg-8Li-1Zn alloy,wherein the HT500 sample exhibits the highest SE,maintaining a value of 106.7–76.9 dB in the frequency range of 30–4500 MHz;this performance has rarely been reported for electromagnetically shielded *** effect was mainly attributed to the multiple reflections of electromagnetic waves caused by the severe impedance mismatch of the abundant phase boundaries,which were in turn provided by the dual-phase(α/β)and secondary ***,the presence of nano-precipitation was also believed to enhance the absorption of electromagnetic waves.
In this work,a novel microwave absorbing material(MAM)made of a pseudo-binary of Sr_(2)TiMoO_(6)-Al_(2)O_(3)(STM)is proposed *** MAMs labeled as STM X(X=60,70,80 and 100,respectively),in which X is the initial weight ...
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In this work,a novel microwave absorbing material(MAM)made of a pseudo-binary of Sr_(2)TiMoO_(6)-Al_(2)O_(3)(STM)is proposed *** MAMs labeled as STM X(X=60,70,80 and 100,respectively),in which X is the initial weight percent of Sr_(2)TiMoO_(6),were synthesized using the solid-state reaction *** with STM100,some equilibrium phases,including SrTiO_(3),Mo,Sr_(8)(Al1_(2)O_(24))(MoO_(4))_(2)and a few undefined ones,are presented in the composites as evidenced by X-ray diffraction results and scanning electron microscopy due to the chemical reaction between Sr_(2)TiMoO_(6)and Al_(2)O_(3)*** conductance loss,heterogeneous interfaces between various equilibrium phases introduce interfacial polarization,which causes an enhancement of dissipation for the incident electromagnetic *** the synthesized samples,STM80 presents the best microwave absorbing *** has a minimum reflection loss(RLmin)of-26 dB and an effective absorbing bandwidth up to 2.7 GHz when the thickness is only 1 *** indicates that STM80 is a new type of microwave absorbing material with strong absorption and ultrathin thickness.
In this study,non-thermal plasma(NTP)was employed to modify the Cu/TiO_(2)adsorbent to efficiently purify H_(2)S in low-temperature and micro-oxygen *** effects of Cu loading amounts and atmospheres of NTP treatment o...
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In this study,non-thermal plasma(NTP)was employed to modify the Cu/TiO_(2)adsorbent to efficiently purify H_(2)S in low-temperature and micro-oxygen *** effects of Cu loading amounts and atmospheres of NTP treatment on the adsorption-oxidation performance of the adsorbents were *** NTP modification successfully boosted the H_(2)S removal capacity to varying degrees,and the optimized adsorbent treated by air plasma(Cu/TiO_(2)-Air)attained the best H_(2)S breakthrough capacity of 113.29 mg H_(2)S/gadsorbent,which was almost 5 times higher than that of the adsorbent without NTP *** studies demonstrated that the superior performance of Cu/TiO_(2)-Air was attributed to increased mesoporous volume,more exposure of active sites(CuO)and functional groups(amino groups and hydroxyl groups),enhanced Ti-O-Cu interaction,and the favorable ratio of active oxygen ***,the X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)results indicated the main reason for the deactivationwas the consumption of the active components(CuO)and the agglomeration of reaction products(CuS and SO_(4)^(2−))occupying the active sites on the surface and the inner pores of the adsorbents.
In this study, a series of polycrystalline Pr2-xGdxNiO4 (PGNO) ceramics doped with Gd were synthesized using the sol-gel technique. The study analyzed the crystal structure, microstructure, valence states, elemental d...
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Efficient interfacial charge transfer and robust interfacial interactions are crucial for achieving the superior spatial separation of carriers and developing efficient heterojunction photocatalysts. Herein, BiOBr/AgB...
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Fine debris is an important component of natural debris *** studies focused primarily on the clay minerals found in the fines,and non-clay minerals were often *** effects of mineralogy of fines on debris-mass slurryin...
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Fine debris is an important component of natural debris *** studies focused primarily on the clay minerals found in the fines,and non-clay minerals were often *** effects of mineralogy of fines on debris-mass slurrying and flow behaviors of the resultant slurries are examined *** fines(≤0.04 mm)in the<5 mm fraction of the Dongyuege Creek debris-flow deposit is replaced with five other mineral powders with the same maximum particle *** types of separate and sequential experiments related to debris slurrying and slurry behaviors are carried out with the prepared clastic *** obtained slurrying index ranging from 0.08 to 0.18 shows that non-clay minerals also can function as the fine fractions of debris-flow materials,so long as the requirement of grain size distribution is ***,non-clay minerals making up fines of debris flows can increase the upper solid concentration limits of slurrying(with a maximum of 0.692)and peak values of relative excess water pressure(measured maximum mean peak value is 0.99),leading to higher momentum and higher competence,and thereby more destructive *** sediments with platy non-clay mineral-dominated fines have potential for mobilizing into small-to medium-size debris flows with a relatively small *** minerals in the fines may indeed enhance the liquefaction potential of debris masses by expanding the difference between upper and lower solid concentration limits of slurrying(0.413 and 0.238,respectively,for pure kaolinite),but they significantly suppress the momentum,competence,and destructive power of potential debris flows by lowering upper solid concentration limit of slurrying of debris *** catchments rich in non-clay minerals,notably those releasing dolomite into loose sediments,may be more prone to threatening and destructive debris *** basin producing clay minerals should be more susceptible to lowmagnitude/high-frequency debris flows
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