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The research object of this paper is the mixed (κ , s) -Riemann–Liouville fractional integral of bivariate functions on rectangular regions, which is a natural generalization of the fractional integral of univariate functions. This paper first indicates that the mixed integral still maintains the validity of the classical properties, such as boundedness, continuity and bounded variation. Furthermore, we investigate fractal dimensions of bivariate functions under the mixed integral, including the Hausdorff dimension and the Box dimension. The main results indicate that fractal dimensions of the graph of the mixed (κ , s) -Riemann–Liouville integral of continuous functions with bounded variation are still two. The Box dimension of the mixed integral of two-dimensional continuous functions has also been calculated. Besides, we prove that the upper bound of the Box dimension of bivariate continuous functions under σ = (σ 1 , σ 2) order of the mixed integral is 3 − min { σ 1 κ , σ 2 κ } where  κ > 0. [ABSTRACT FROM AUTHOR]

In present work, the evolution of scalar field and electromagnetic field under the background of the charged black-bounce spacetimes are investigated, and we obtain an obvious echoes signal which appropriately reports the properties of the charged black-bounce spacetimes and disclose the physical reasons behind such phenomena. Furthermore, by studying the quasinormal ringdown, we analyze the three states of the charged black-bounce spacetimes in detail, our results show that the echoes signal only appears when (| Q | ≤ m) and (| l | > m + m 2 - Q 2 ) in this spacetime, while when the parameters demand (| Q | > m) , the echoes signal will be transformed into a quasinormal ringdown of the two-way traversable wormhole, and the charged black-bounce is a regular black hole with normal horizons by requiring (| Q | ≤ m) and (| l | < m - m 2 - Q 2 ) . [ABSTRACT FROM AUTHOR]

In this study, a new, effective procedure is proposed for identifying the surface roughness from the responses recorded of two connected test vehicles moving over the bridge. Central to this study is the proposal of a simple static correlation formula for relating the dynamic deflections of the two vehicles's contact points on the bridge, via the displacement influence lines (DILs). With the aid of this relation, the roughness formula for estimating the bridge surface profile is derived using the responses of the leading and following vehicles. It does not require any prior knowledge of the dynamic properties of the bridge. The efficacy of the proposed procedure is validated for both the simple and three-span continuous beams by the finite element method (FEM). Also, a parametric study is conducted for various physical properties of the test vehicles. It is confirmed that the roughness profiles back-calculated from the proposed formula agree excellently with the assumed ones for both the simple and continuous beams. For use in practice, the two connected test vehicles should not be designed too heavy and not to move at too fast speeds, in order to reduce the impact on the bridge. [ABSTRACT FROM AUTHOR]

The study of the relative phase between strong and electromagnetic amplitudes is of great importance for understanding the dynamics of charmonium decays. The information of the phase can be obtained model-independently by fitting the scan data of some special decay channels, one of which is ψ′ →K+K-. To find out the optimal data taking strategy for a scan experiment in the measurement of the phase in ψ′ →K+ K-, the minimization process is analyzed from a theoretical point of view. The result indicates that for one-parameter fit, only one data taking point in the vicinity of a resonance peak is sufficient to acquire the optimal precision. Numerical results are obtained by fitting simulated scan data. Besides the results related to the relative phase between strong and electromagnetic amplitudes, the method is extended to analyze the fits of other resonant parameters, such as the mass and the total decay width of ψ′. [ABSTRACT FROM AUTHOR]

A Bloom filter is a simple space-efficient randomised data structure allowing membership queries over data sets. It is widely utilised in peer-to-peer network, traffic measurement and distributed systems. Aiming at the deficiencies of the naïve counting Bloom filters (NCBFs), a novel data structure called balanced counting Bloom filters (BCBFs) is presented. In order to achieve space-efficient storage and effective query, the BCBF adopts the following methods: introducing hash fingerprints, partitioning bucket vectors into equally sized segments and storing elements with the least load bucket. Analytical expressions are deduced in detail based on the theory of differential equations and probability. Besides, simulations are conducted based on the data produced by computer and real network trace. The results demonstrate that the BCBF cannot only serve the same functionality as the NCBF using much less space, but also becomes a valuable tool in hardware to scale the high-speed link. [ABSTRACT FROM AUTHOR]

Wheat lines known as ‘Lankao 90(6)’, derived from the cross ‘Mzalenod Beer’ (hexaploid triticale)/‘Baofeng 7228’//‘90 Xuanxi’, carry a recessive powdery mildew resistance gene temporarily named PmLK906. Gene PmLK906 appears to be different from known wheat powdery mildew resistance genes. PmLK906 was tagged using microsatellite markers in a segregating population derived from the cross ‘Chinese Spring’/‘Lankao 90(6)21-12’. The dominant microsatellite marker Xgwm265-2AL was linked in repulsion with PmLK906 at a genetic distance of 3.72 cM, whereas the co-dominant Xgdm93-2AL was linked to PmLK906 at a genetic distance of 6.15 cM. Both markers were placed on chromosome arm 2AL using ‘Chinese Spring’ nulli-tetrasomic lines. The recessive PmLK906 has a different specificity to the dominant resistance alleles located at the Pm4 locus and appeared to be located to a locus different from Pm4. [ABSTRACT FROM AUTHOR]

Tuning hydrogen-bonding of discotic liquid crystal can result in more ordered columnar mesophases and higher charge carrier mobility materials. In this paper, triphenylene derivatives with one, two and three amide groups with structure of C18H6(OR)5(OCH2CONHBu), C18H6(OC5H11)4(OCH2CONHBu)2 and symmetrical and asymmetrical C18H6(OR)3(OCH2CONHBu)3 (R = CnH2n+1, n = 4-9) respectively were designed and synthesized. The results showed that each intra-columnar H-bond forming amide (-CONH-) group caused an average increase of 22°C in clearing point from the non-H-bonding ester group (-COO-) triphenylene analogous. This was the first quantitative result of H-bonding on the stabilization of columnar mesophase. [ABSTRACT FROM AUTHOR]

The ethylene–propylene–diene terpolymer (EPDM) foam article was prepared by mixing a compound in a two roll mill, extruding the compound through a cold feed extruder and finally vulcanising the extrudate in a circulating hot air oven. The blowing kinetics of EPDM compounds was studied using a moving die rheometer, and the effect of blowing agent content and process temperature on the cell structures was investigated. The results show that kinetic parameters determined from the autocatalystic model equation have good agreement with the experimental results. The calculated activation energy of azodicarbonamide (AC) decomposition is higher than that of rubber cure, which indicates the rate of blowing agent AC decomposition accelerates more quickly than that of rubber vulcanisation with increasing temperature. The density of foam article decreases with increasing blowing agent content or elevated temperature. The foams have a closed cell structure and the larger cells inlay among the smaller cells, which shows cell materials with structural multihierarchy. This shows the rubber vulcanisation and blowing agent decomposition could match only using extremely slow accelerator diphenylguanidine (DPG), which is dissimilar to the conventional EPDM sponge requiring very quick scorch. [ABSTRACT FROM AUTHOR]

An effective technique is proposed for identifying the track modulus, i.e., the foundation stiffness of the rails, using the contact-point response of the moving test vehicle. First, for a simple beam resting on an elastic foundation under a moving sprung mass, closed-form solutions are derived for the responses of the vehicle and its contact point with the rail. It is shown that the track modulus can be well identified via the first rail frequency (RF) extracted from the contact-point response, in that (1) the first RF is most outstanding compared with the other RFs in the vehicle-generated responses; and (2) the contact-point response outperforms the vehicle response as it is free of the disturbing effects of the vehicle and driving frequencies. The proposed technique is then verified numerically along with the key parameters assessed. The main conclusions are: (1) the first RF can be easily recognized as the "cliff" of the RF "plateau" in the contact-point spectrum; (2) the track irregularity has a little effect on the identification of track modulus; (3) a moderate speed is recommended for the test vehicle for a balance between efficiency and accuracy; and (4) the efficacy of the proposed technique remains good even with the presence of track damping and irregularity. Moreover, the application of the proposed technique to detecting the damage modeled by variation in foundation stiffness is demonstrated. [ABSTRACT FROM AUTHOR]

4.2 K photoluminescence (PL) and 77 K standard Hall-effect measurements were performed for In0.52Al0.48As/InxGa1-xAs metamorphic high-electron-mobility-transistor (HEMT) structures grown on GaAs substrates with different indium contents in the InxGa1-xAs well or different Si delta-doping concentrations. It was found that electron concentrations increased with increasing PL intensity ratio of the “forbidden” transition (the second electron subband to the first heavy-hole subband) to the sum of the “allowed” transition (the first electron subband to the first heavy-hole subband) and the forbidden transition. And electron mobilities decreased with increasing product of the average full width at half maximum of allowed and forbidden transitions and the electron effective mass in the InxGa1-xAs quantum well. These results show that PL measurements are a good supplemental tool to Hall-effect measurements in optimization of the HEMT layer structure. [ABSTRACT FROM AUTHOR]

A step-graded InAlAs buffer layer and an In[sub 0.52]Al[sub 0.48]As/In[sub 0.53]Ga[sub 0.47]As metamorphic high electron mobility transistor (MM-HEMT) structures were grown by molecular beam epitaxy on GaAs (001) substrates, and rapid thermal annealing was performed on them in the temperature range 500–800 °C for 30 s. The as-grown and annealed samples were investigated with Hall measurements, and 77 K photoluminescence. After rapid thermal annealing, the resistivities of step-graded InAlAs buffer layer structures became high. This can avoid leaky characteristics and parasitic capacitance for MM-HEMT devices. The highest sheet carrier density n[sub s] and mobility μ for MM-HEMT structures were achieved by annealing at 600 and 650°C, respectively. The relative intensities of the transitions between the second electron subband to the first heavy-hole subband and the first electron subband to the first heavy-hole subband in the MM-HEMT InGaAs well layer were compared under different annealing temperatures. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Objective: To identify the clinical characteristics, treatment, and prognosis of relapsing polychondritis patients with airway involvement. Methods: Twenty-eight patients with relapsing polychondritis, hospitalised in the First Hospital of Shanxi Medical University between April 2011 and April 2021, were retrospectively analysed. Results: Fifty per cent of relapsing polychondritis patients with airway involvement had a lower risk of ear and ocular involvement. Relapsing polychondritis patients with airway involvement had a longer time-to-diagnosis (p < 0.001), a poorer outcome following glucocorticoid combined with immunosuppressant treatment (p = 0.004), and a higher recurrence rate than those without airway involvement (p = 0.004). The rates of positive findings on chest computed tomography and bronchoscopy in relapsing polychondritis patients with airway involvement were 88.9 per cent and 85.7 per cent, respectively. Laryngoscopy analysis showed that 66.7 per cent of relapsing polychondritis patients had varying degrees of mucosal lesions. Conclusion: For relapsing polychondritis patients with airway involvement, drug treatment should be combined with local airway management. [ABSTRACT FROM AUTHOR]

To explore the protective mechanisms of brassinosteroids in the chill-induced photoinhibition in tomato (Solanum lycopersicum), we studied the effect of foliar sprayed 24-epibrassinolide (EBR, 0.1µM) on the gas exchange, chlorophyll fluorescence characteristics, and chlorophyll a fluorescence transient in tomato seedlings under chilling stress (a temperature of 8 °C and an irradiance of 200 µmol m-2 s-1) for 4 d. Results showed that chilling significantly inhibited CO2 assimilation and induced photoinhibition of photosystem II (PS II). However, photosystem I (PS I) was relatively tolerant to chilling stress, which was due to the downregulation of PS II activity and increase of cyclic electron transport around PS I (CEF). Chilling led to the inactivation of PS II reaction centers (RCs) and blocked the electron transport at the PS II acceptor side, but did not affect the oxygen-evolving complex (OEC) on the donor side of PS II. Exogenous EBR could alleviate chill-induced PS II photoinhibition mainly by the increase of CO2 assimilation and thermal dissipation of excitation energy in the PS II antennae, while the protective effect of CEF was relatively smaller. This study demonstrated that EBR maintained the stability of the electron transport chain and the function of PS II in chilled tomatoes. EBR promoted the absorption (ABS/CS), trapping (TRo/CS), and electron transport (ETo/CS) per leaf area in tomatoes under chilling stress, which was due to increasing the density of active reaction centers (RC/CS), rather than the activity of active RCs. [ABSTRACT FROM AUTHOR]

Boron carbon nitride (BCN) films were synthesized on Si (100) and fused silica substrates by radio-frequency magnetron sputtering from a B4C target in an Ar/N2 gas mixture. The BCN films were amorphous, and they exhibited an optical band gap of ~1.0 eV and p-type conductivity. The BCN films were over-coated with ZnO nanorod arrays using hydrothermal synthesis to form BCN/ ZnO-nanorods p-n heterojunctions, exhibiting a rectification ratio of 1500 at bias voltages of ±5 V. [ABSTRACT FROM AUTHOR]

To explore the protective mechanisms of brassinosteroids in the chill-induced photoinhibition in tomato (Solanum lycopersicum), we studied the effect of foliar sprayed 24-epibrassinolide (EBR, 0.1µM) on the gas exchange, chlorophyll fluorescence characteristics, and chlorophyll a fluorescence transient in tomato seedlings under chilling stress (a temperature of 8 °C and an irradiance of 200 µmol m-2 s-1) for 4 d. Results showed that chilling significantly inhibited CO2 assimilation and induced photoinhibition of photosystem II (PS II). However, photosystem I (PS I) was relatively tolerant to chilling stress, which was due to the downregulation of PS II activity and increase of cyclic electron transport around PS I (CEF). Chilling led to the inactivation of PS II reaction centers (RCs) and blocked the electron transport at the PS II acceptor side, but did not affect the oxygen-evolving complex (OEC) on the donor side of PS II. Exogenous EBR could alleviate chill-induced PS II photoinhibition mainly by the increase of CO2 assimilation and thermal dissipation of excitation energy in the PS II antennae, while the protective effect of CEF was relatively smaller. This study demonstrated that EBR maintained the stability of the electron transport chain and the function of PS II in chilled tomatoes. EBR promoted the absorption (ABS/CS), trapping (TRo/CS), and electron transport (ETo/CS) per leaf area in tomatoes under chilling stress, which was due to increasing the density of active reaction centers (RC/CS), rather than the activity of active RCs. [ABSTRACT FROM AUTHOR]

Shubnikov–de Haas measurements were carried out for In[sub 0.52]Al[sub 0.48]As/In[sub x]Ga[sub 1-x]As metamorphic high-electron-mobility-transistor structures grown on GaAs substrates with different indium contents and/or different Si δ-doping concentrations. Zero-field (B→0) spin splitting was found in samples with stronger conduction band bending in the InGaAs well. It was shown that the dominant spin splitting mechanism is attributed to the contribution by the Rashba term. We found that zero-field spin splitting not only occurs in the ground electron subband, but also in the first excited electron subband for a sample with Si δ-doping concentration of 6×10[sup 12] cm[sup -2]. We propose that this In[sub 0.52]Al[sub 0.48]As/In[sub x]Ga[sub 1-x]As metamorphic high-electron-mobility-transistor structure grown on GaAs may be a promising candidate spin-polarized field-effect transistors. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The geometrical structures, relative electronic and magnetic properties of small AlCo (1 ≤ n ≤ 9) clusters are systematically investigated within the framework of density functional theory at the BPW91 level. The single Co doping can dramatically affect the ground state geometries of the 1 Al clusters. At the same time, the resulting geometries show that the lowest energy AlCo clusters prefer to be three dimensional structures. Here, the relative stabilities are investigated in terms of the calculated average binding energies, fragmentation energies, and second-order energy differences. Moreover, the result of the highest occupiedlowest unoccupied molecular orbital energy gaps indicates that AlCo clusters have the highest chemical stability for AlCo (1 ≤ n ≤ 9) clusters. Furthermore, the natural population analysis reveals that the charges in AlCo clusters transfer from the Al frames to the Co atom. Additionally, the analyses of the local and total magnetic moments of the AlCo clusters show that the magnetic effect mainly comes from the Co atom. [ABSTRACT FROM AUTHOR]

A series of triphenylene discotic liquid crystals with amido-based alkyl chains in different lengths were synthesized and characterized. The liquid crystal properties were studied with differential scanning calorimetry and polarizing optical microscopy. The influences of amide alkyl chain lengths on the mesomorphism were discussed. Based on the results, we concluded that the triphenylene discogens with an amido-based alkyl chain could form intermolecular hydrogen bonds inside their columnar stacks, and hence, exhibit higher melting and clearing points, and wider mesophase ranges. [ABSTRACT FROM AUTHOR]

Chlorophyll (Chl) degradation was found to be related to the endogenous gibberellin (GA) content in shoots during senescence in the perennial plant Paris polyphylla var. yunnanensis (Franch.). Treatment with gibberellic acid (GA3) significantly increased the content of endogenous GAs (GA4 + GA7), retarded the senescence of shoots, and the degradation of proteins and Chl. Chlorophyllase, Mg-dechelation and peroxidase activities increased more in control plants than in those treated with GA3. GA3 treatment also protected lipoxygenase activity, which decreased significantly in control plants. [ABSTRACT FROM AUTHOR]

Aims: To investigate the effect of tea polyphenol (TP) and Candida ernobii alone or in combination against postharvest disease ( Diplodia natalensis) in citrus fruit and to evaluate the possible mechanisms involved. Methods and Results: TP at concentrations of 0·1%, 0·5% and 1·0% alone, or in combination with C. ernobii (1 × 106 CFU ml−1), showed a lower infection rate of stem-end rot. TP at the concentration of 0·5% or above significantly inhibited the spore germination of D. natalensis. TP at the concentration of 1·0% showed inhibitary ability on mycelium growth of D. natalensis. The addition of TP did not affect the growth of C. ernobii in vitro and significantly increased the population of C. ernobii in vivo. Conclusions: TP exhibited an inhibitory effect against D. natalensis and improved the biocontrol efficacy of C. ernobii. It was direct because of the inhibitory effects of TP on spore germination and mycelial growth of D. natalensis in vitro and indirect because of the increased populations of C. ernobii in vivo. Significance and Impact of the Study: The results suggested that TP alone or in combination with biocontrol agents has great potential in commercial management of postharvest diseases in fruits. [ABSTRACT FROM AUTHOR]

Intermolecular hydrogen bond is an efficient way to anchor columnar assembly of discotic liquid crystals, and would result in more ordered columnar mesphase and faster charged carrier mobility. In this report, a series of peripheral functionalized triphenylene derivatives, C18H6(OC6H13)4(OCH2CONHR)2, which contains amide groups at the 2,7-positions, have been synthesized. The polarized optical microscopy (POM) and differential scanning calorimetry (DSC) results showed that these compounds exhibit hexagonal columnar mesophases. The triphenylene derivatives gelate in the solution of octane, petroleum ether, cyclohexane and p-xylene and form stable organic gels. The xerogels formed from organic solvents were analyzed by scanning electron microscope (SEM) and showed fiber-like or sponge-like morphology. It is demonstrated that intermolecular hydrogen bonds stabilize the columnar molecular organization and assembly in mesomorphic state and organic gel. [ABSTRACT FROM AUTHOR]

Click chemistry between alkynes and azides high efficiently produces triazoles and would be a convenient tool for synthesis of discotic liquid crystal dimers, oligomers and polymers. In this report, triphenylenes containing terminal alkynes and azides were prepared, and the cycloaddition reaction (click chemistry) between them catalyzed by CuI-Et3N in toluene produced discotic liquid crystal dimers in high yield and good selectivity. The dimers and intermediates have been fully characterized by 1H NMR and high resolution MS. Polarized optical microscopy (POM) and differential scanning calorimetry (DSC) results show the dimers possess columnar mesophase in wide temperature range from very low temperature. The triazole moiety in the dimer can act as electron and hydrogen bond acceptor, and ionic forming part, rich chemical and physical properties can be expected from these new structure discotic dimers. [ABSTRACT FROM AUTHOR]

After applying an electrical current pulse (ECP) to samples of Cu–Zn alloy, {111} oriented nanotwins parallel to the ECP direction in α phase grains have been observed at ambient temperature. It seems that (a) these samples have heated up to a temperature much higher than the α to β phase transformation temperature and (b) new β nuclei on the {110} planes have formed in the original α phase. As a result, with the samples being rapidly cooled, these oriented nanotwins will be formed with the β to α martensitic transformation. [ABSTRACT FROM AUTHOR]

In this letter, it is found that when the critical electric current pulse (ECP) passes through a Cu–Zn alloy with lead inclusions, those inclusions will disappear and transfer into grain boundaries or defects, forming many dispersed small particles of lead. Such kind of lead transfer can be produced by no other heat treatments than ECP. The theoretical analysis points out that this phenomenon is attributed to its specific effect on reducing considerably the diffusion activation energy of lead in the alloy. Therefore, the ECP treatment would provide a promising method to refine materials and to improve their physical properties. [ABSTRACT FROM AUTHOR]

A Shubnikov–de Haas (SdH) oscillation measurement was performed on highly doped InAlAs/InGaAs metamorphic high-electron-mobility transistors on GaAs substrates at a temperature of 1.4 K. By analyzing the experimental data using fast Fourier transform, the electron densities and mobilities of more than one subband are obtained, and an obvious double-peak structure appears at high magnetic field in the Fourier spectrum. In comparing the results of SdH measurements, Hall measurements, and theoretical calculation, we found that this double-peak structure arises from spin splitting of the first-excited subband (i=1). Very close mobilities of 5859 and 5827 cm[sup 2]/V s are deduced from this double-peak structure. The sum of the carrier concentration of all the subbands in the quantum well is only 3.95×10[sup 12] cm[sup -2] due to incomplete transfer of the electrons from the Si δ-doped layer to the well. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

InAlAs/InGaAs metamorphic high-electron-mobility transistor structures with different spacer layers on GaAs substrates are characterized by Raman measurements. The influence of In[sub 0.52]Al[sub 0.48]As spacer thickness on longitudinal optic phonon–plasmon coupling is investigated. It is found that the intensity of GaAs-like longitudinal optic phonon, which couples with collective intersubband transitions of two-dimensional electron gas, is strongly affected by the different subband energy spacings, subband electron concentrations, and wave function distributions, which are determined by different spacer thicknesses. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Linked Content This article is linked to Kang et al paper. To view this article visit https://doi.org/10.1111/apt.14275. [ABSTRACT FROM AUTHOR]