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51.
《Information and Software Technology》2005,47(3):199-214
Software testing is an important technique to assure the correctness of the software. One of the essential prerequisite tasks of software testing is test data generation. This paper proposes an approach to generate test data specifically for dynamic pointer structures. In our context, a pointer is considered and handled as a location in memory, represented by a dynamic linear array that expands and shrinks during execution. As such, pointer test data can be directly generated from this linear array. The proposed technique can also support any dynamic structures, as well as homogeneous and heterogeneous recursive structures. 相似文献
52.
《Wear》2006,260(7-8):847-854
Laser shock processing (LSP) is becoming an important surface treatment to induce a compressive residual stress field, which improves fatigue and fracture properties of components. In this work, we examine the effect of laser shock processing on the wear and friction behavior of 6061-T6 aluminum alloy. Wear rate and friction coefficient evolution are investigated for different process parameters of LSP. Roll-on-flat tribometer is used with different loading conditions. Hardness and residual stresses are assessed as well. It is observed that wear rate decreases as pulse density increases; this is explained in light of residual stress distribution. 相似文献
53.
《Materials Letters》2005,59(14-15):1893-1896
Dye-sensitized solar cells (DSSCs) were constructed using nanostructured core–shell working electrodes produced by a sol–gel method. The precursor chemistry was studied by comparing zirconium butoxide and zirconium isopropoxide. Additionally, the concentrations in polar solvents were altered and used on two different titania nanostructures. The electrodes were characterized by photoelectrochemical measurements (PECM). The best efficiencies were recorded for the working electrodes modified with 0.05 M zirconium butoxide in n-butanol at 2.29% from 1.36% (uncoated TiO2) for P25 films and 2.06% from 1.38% (uncoated TiO2) for anatase films under a light intensity of 0.1 Sun. 相似文献
54.
Eva Marcuzzo Donatella Peressini Frédéric Debeaufort Alessandro Sensidoni 《Innovative Food Science and Emerging Technologies》2010,11(3):451-457
Gluten films obtained in acid conditions display some protein dispersion difficulties. Ultrasound treatment (UT) could represent an interesting strategy for improving gluten film appearance. Different UT exposure times were applied to film-forming dispersion. The aim of this work was to investigate the effect of ultrasound treatment on gluten-based films at molecular and mesoscopic levels. Distribution in gliadin and glutenins was determined with SE-HPLC. The UT improved protein dispersion and final film appearance. Sonication did not lead to large changes in various gluten fractions, which suggests absence of important protein breakdown at the molecular level. Gluten showed high tolerance to UT. Surface properties of untreated and treated films were investigated by contact angle measurement: sonication promoted hydrophilic surface properties.Industrial relevanceBio-based packaging has been receiving increasing attention in view of its beneficial impact on the environment. Among proteins, gluten resulted as a very interesting film-forming material. Gluten films prepared in acid conditions showed problems in protein dispersion. Sonication represents a physical strategy which allowed us to obtain gluten-based films without the addition of chemical additives, such as sodium sulphite. 相似文献
55.
《International Journal of Hydrogen Energy》2019,44(2):707-719
S-doped meso/macroporous g-C3N4 spheres (SMCN) were successfully synthesized via an in situ novel method utilizing millimeter-scale porous silica spheres as template and thiourea as precursor and S source. Such SMCN possessed millimeter-scale spherical morphology with continuous channels at 20–80 nm in the interior of the spheres, and exhibited increased H2 generation rate (15 times) and phenol degradation rate (5 times) under visible light irradiation compared with that over pristine g-C3N4, mainly due to the enlarged surface area, enhanced mass transfer and improved efficiency of charges separation all stemming from the synergetic effects of the S doping and pore creating. Notably, density functional theory (DFT) calculations were employed to further understand the mechanism of the photocatalytic enhancement with regard to the optical absorption property at atomic level. Combined with the finite difference time domain (FDTD) simulations aiming at evaluating the effect of the nanoscale pore architecture on the optical absorption ability, it was revealed that not only the S doping but also the meso/macroporous structure resulted in the enhancement of the optical absorption, which was considered to be an essential role for the enhanced photocatalytic performances over SMCN. 相似文献
56.
《Ceramics International》2019,45(10):13099-13111
We introduce a facile way to improve the performance of NiCo2O4 electrode by including a Ni seed layer. The seed layer deposited on Ni foam electrode (NiCo2O4/Ni@NF) shows the superior specific capacity of 1142 C g−1 at 1 A g−1 with the excellent cycle stability of ∼96% even after 5000 cycles at a higher current density of 5 A g−1. These values are about 3.7 times higher than that of the electrode (NiCo2O4@NF) without a seed layer, which shows the specific capacity of 305 C g−1@1 A g−1 with cycle stability of 84% even at a lower current density of 1 A g−1. The enhanced performance of the NiCo2O4/Ni@NF electrode may be attributed to lower interface resistance, fast redox reversible reaction, and improved surface active sites. Further, the asymmetric solid-state supercapacitor device is fabricated by using the NiCo2O4/Ni@NF electrode as a positive and reduced graphene oxide (rGO)-Fe2O3 nanograin as a negative electrode with PVA-KOH gel electrolyte, and the NiCo2O4/Ni20@NF//rGO-Fe2O3@NF asymmetric solid state device delivers an areal capacitance of 446 mF cm−2 with a low capacitance loss of 18% even after 10000 cycles. Further, the fabricated asymmetric solid state device shows a maximum energy density of 124.3 Wh cm−2 (at 3.58 kW cm−2) and power density of 14.88 kW cm−2 (at 31.41 Wh cm−2). 相似文献
57.
Chencheng Wang Feng Chen Yuanzheng Tang Xiao Chen Junchao Qian Zhigang Chen 《Ceramics International》2018,44(6):5834-5841
Biologically structured carbon/cerium dioxide materials are synthesized by biological templates. The microscopic morphology, structure and the effects of different oxidation temperatures on materials are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) ultraviolet-visible light spectrum (UV–Vis) and X-ray Photoelectron Spectroscopy (XPS). Moreover, by splitting water under visible light irradiation, the hydrogen production is measured to test the photocatalytic property of these materials. The results show that materials made with bamboo biological templates which are immersed in 0.1 mol L?1 of cerium nitrate solution, then carbonizated in nitrogen (700 °C) and oxidized in air (500–600 °C), can obtain the biological structure of bamboo leaves. The product is in the composition of hybrid multilayer membrane, which one is carbon membrane form plant cell carbonation and another is ceria membrane by nanoparticle self assembly. The best oxidation temperature is 550 °C and the band gap of carbon/cerium dioxide materials synthesized at this optimum oxidation temperature could be reduced to 2.75 eV. After exposure to visible light for 6 h, the optimal hydrogen production is about 302 μmol g?1, which is much higher than that of pure CeO2. 相似文献
58.
Dry sliding wear tests were performed for Ti–6Al–4V alloy on a pin-on-disc wear tester. The wear behavior of Ti–6Al–4V alloy at sliding velocities of 0.5–4 m/s was studied and the tribo-oxides and their function were explored. Ti–6Al–4V alloy presented a marked variation of wear rate as a function of velocity. With the rise and fall of wear rate, Ti–6Al–4V alloy underwent the transitions of wear mechanisms from the combination of delamination wear and oxidative wear at lower speeds to delamination wear at 2.68 m/s, and then to oxidative wear at 4 m/s. These phenomena were attributed to the appearance and disappearance of tribo-oxides. In spite of trace or a small amount, tribo-oxides would change the wear behavior, and even wear mechanism. 相似文献
59.
《International Journal of Hydrogen Energy》2020,45(51):27202-27209
The catalytic mechanism and activity of transition metal atom doped C2N (M-C2N, M = Fe, Co, Ni, and Cu) for the oxygen reduction reaction (ORR) are investigated in detail by density functional theory method. All the screened M-C2N are thermodynamically stable based on the binding energy calculations. The adsorption energy results indicate that the adsorption strength of O2 and ORR intermediates are decreased in the order of Fe-C2N ˃ Co-C2N ˃ Ni-C2N ˃ Cu-C2N, in which the adsorption energy values on Cu-C2N are most close to those on the Pt(111). Based on the relative energy diagram of ORR, the energetically favorable pathway on Fe-C2N and Co-C2N is direct 4e− mechanism, in which the O–O bond is directly dissociated after the second electron transfer. While for Ni-C2N and Cu-C2N, the most favorable pathway is indirect 4e− mechanism, in which the H2O2 is formed as the intermediate product. For all studied M-C2N, the Ni-C2N and Cu-C2N hold better catalytic activity, which could attribute to the contribution of metal atom and part of its activated nitrogen atoms. 相似文献
60.
《Ceramics International》2019,45(15):18614-18622
Low ionic conductivity at room temperature and poor interfacial compatibility are the main obstacles to restrain the practical application of polymer solid electrolytes. In this work, lanthanum zirconate (LZO) fibers were prepared by electrospinning method and used for the first time as fillers in sandwich polypropylene carbonate (PPC)-based solid electrolyte. Meanwhile, a graphite coating was applied on one surface of the composite solid electrolyte (CSE) membrane. The results show that the LZO fibers significantly increases the room-temperature electrochemical performance of the CSE, and the graphite coating enhances the interfacial compatibility between electrolyte and lithium anode. Furthermore, an ultra-thin PPC-LZO CSE with a total thickness of 22 μm was prepared and used in NCM622/CSE/Li solid-state cell, which shows an initial discharge capacity of 165.6 mAh/g at the current density of 0.5C and a remaining capacity of 113.0 mAh/g after 250 cycles at room temperature. Rise to 1C, the cell shows an initial discharge capacity of 154.2 mAh/g with a remaining capacity of 95.6 mAh/g after 250 cycles. This ultra-thin CSE is expected to be widely applied in high energy-density solid-state battery with excellent room-temperature electrochemical performances. 相似文献