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1

Ocena termicznego zagrożenia reakcji syntezy związków metaloorganicznych za pomocą kalorymetrii reakcyjnej

Geng Laihong, Li Weiping, Yang Zhigang, Guo Kai, Wang Tao, Wei Jinlong

Przemysł Chemiczny

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2023

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T. 102, nr 7

674--682

PL

Dziesięć reakcji syntezy związków metaloorganicznych oceniono pod kątem zagrożenia termicznego w warunkach adiabatycznych, wykorzystując kalorymetrię reakcyjną. Określono maksymalne temperatury badanych reakcji i adiabatyczny wzrost temperatury. Syntezy chlorku cykloheksylomagnezowego i butylolitu wykazały największe wartości ciepła właściwego i najwyższe maksymalne temperatury osiągnięte po 24 h w warunkach adiabatycznych.

EN

Ten reactions of synthesis of organometallic compds. were assessed by reaction calorimetry for thermal hazard under adiabatic conditions. The max. temps. of the studied reactions and adiabatic temperature rise were detd. The synthesis of cyclohexylmagnesium chloride and BuLi showed the highest sp. heats and highest max. temps. reached after 24 h under adiabatic conditions.

2

Manipulating far-field ring-shaped array according to the superposition of weight functions

Yuan Chenyuan, Yuan Caifu, Xiang Sufen, Ji Xiaoling, Wang Tao

Optica Applicata

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2023

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Vol. 53, nr 1

87--98

EN

In order to control the distribution characteristics of the far-field ring-shaped array, we introduce a new light source to produce adjustable far-field distribution by the method of weight function superposition. It has been shown that, by changing the parameters of the light source, one can obtain far-field with various distribution, including distribution with decrease in spectral intensity of specified rings, distribution with disappearances of specified rings, distribution with different spectral intensity of part of lobes in the continuous rings, distribution with part of the lobes in specified rings disappearing and distribution with some lobes in specified rings being stronger. These results will produce some novel far-field distributions which may provide a new idea for further study concerning about the manipulations of far-field array distribution.

3

Degree of paraxiality of a multi-Gaussian beam diffracted by a circular aperture

Cheng Jinping, Xiao Yingying, Wu Hao, Ji Xiaoling, Wang Tao

Optica Applicata

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2023

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Vol. 53, nr 4

621--631

EN

The degree of paraxiality (DOP) of a diffracted multi-Gaussian beam is discussed. It is shown that the DOP of the multi-Gaussian beam will decrease as it is diffracted by a circular aperture, and the DOP of the diffracted multi-Gaussian beam is influenced by both the aperture radius and the characteristics of beam source. As an example, the dependence of the DOP on the aperture radius, the boundary characteristic, and the beam waist width is investigated.

4

Analysis of the influence of warning sounds in expressway tunnels on the mental state and attention of the driver

Xiao Yao, Liang Bo, Wang Tao, Niu Jiaan, He Shiyong

Archives of Civil Engineering

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2023

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Vol. 69, nr 2

623--636

EN

In recent years, some expressway tunnels have started broadcasting warning sounds, such as fire alarms, to improve driver attention and traffic safety. However, there is few research on it, and in contrast to previous studies, we have considered different evaluation indices and through field measurement to determine the effectiveness of this practice. The characteristics of three warning sound signals, i.e., fire alarm, dynamic music, and voice command, in a tunnel were analyzed using MATLAB. Considering pupil diameter and blink duration as evaluation indexes, the change in the mental state of the driver after hearing a warning sound was analyzed. Based on Markov chain theory, the change in the gaze region and gaze shift of the driver under the condition of a warning sound was analyzed. Results shows fire alarms and voice commands can increase the mental load of drivers, but the degree of impact was not determined. Dynamic music does not affect the mental load of the driver. The fire alarm and dynamic music attracted the attention of the driver; conversely, as the voice command warns the driver to focus on safety, it did not impact the attention of the driver. The research results provide a scientific reference for the selection of warning sounds in expressway tunnels and new research ideas for the prevention of traffic injuries in expressway tunnels.

5

Diffraction enhancement using the double sparse dictionary method

Wang Tao, Peng Suping, Lin Peng, Cui Xiaoqin, Zhou Jiawei

Acta Geophysica

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2023

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Vol. 71, no. 3

1259--1271

EN

Seismic diffraction delivers high-precision imaging of subsurface discontinuities and objects. As diffraction is characterised by weak energy, separating diffraction from full wavefields is an essential pre-imaging step. However, traditional diffraction separation methods generally produce unsatisfactory separation results for datasets with low signal-to-noise ratios. Accordingly, we propose a novel diffraction separation method that incorporates plane-wave destruction and the double sparse dictionary algorithm to improve separation quality. The plane-wave destruction method is used to suppress strong reflection, whereas the double sparse dictionary can simultaneously extract diffracted signals. A robust plane-wave destruction method using the Hilbert transform is employed to improve the stability and accuracy of slope estimation. The double sparse dictionary algorithm has better performance when sparsely representing seismic signals and can effectively extract weak diffraction with a high signal-to-noise ratio. Synthetic and field examples demonstrate the effectiveness of the proposed method in removing strong reflection and enhancing weak diffraction. Overall, the proposed method is conducive to detect small structures and offers a new resource for seismic structural interpretation.

6

The far-zone behaviors of light waves on scattering from particulate medium with various distribution

Dai Qihang, Xie Zhongyuan, Pan Xiaoning, Ji Xiaoling, Wang Tao

Optica Applicata

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2022

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Vol. 52, nr 2

273--282

EN

The far-zone spectral density of light waves scattered on a particulate medium was discussed, and the influence of characteristics of the medium on the far-zone scattered spectral density was investigated. It is shown that the normalized spectral density of the scattered field is closely related with the structural characteristics of the particles collection, including the relative size of particles and the distribution information of particles in the collection. These results may provide potential application in the reconstruction of the structure information of particulate medium.

7

Influence of Annealing Treatment on Deep Drawing Behavior of Q235 Carbon Steel /410/304 Stainless Steels Three-Layer Composite Plate

Lv Zehua, Zhang Zhixiong, Han Jianchao, Wang Tao

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 2

421--433

EN

Effect of annealing treatment on deep drawing behavior of hot-rolled Q235 carbon steel/410/304 stainless steel three-layer composite plate was investigated. Deep drawability of the unannealed composite plates exhibits a sharp difference for various contact surfaces with the die. The limit drawing ratio (LDR) of the composite plate with the carbon steel contacting the die is 1.75, while it is 1.83 with the stainless steel contacting the die due to the different mechanical responses to the tensile stress at the corner of the die. After annealing at 900°C for 2 h, however, the deep drawabilities of the composite plates both for various contact surfaces with the die are significantly improved and becomes almost identical, which are attributed to the stress relief, the enhanced ductility and the improved interface bonding strength of the hot-rolled component plates during annealing.

8

Light waves scattering from an anisotropic semi-soft boundary medium with spectral dependence

Huang Zhiru, Dai Qihang, Ji Xiaoling, Wang Tao

Optica Applicata

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2021

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Vol. 51, nr 2

271--280

EN

The far-zone behavior of polychromatic light waves on scattering from an anisotrophic semi-soft boundary medium with spectral dependence was considered, and the spectral density and the spectral degree of coherence of the far-zone scattered field were investigated. It is shown that the distributions of the spectral density and the spectral degree of coherence of scattered field are closely related with the rms width, the center wavelength, and the maximum value of the center wavelength of the scattering potential of the scattering medium.

9

Simulation studies on the influence of other combustible gases on the characteristics of methane explosions at constant volume and high temperature

Luo Zhenmin, Liu Litao, Gao Shuaishuai, Wang Tao, Su Bin, Wang Lei, Yang Yong, Li Xiufang

Archives of Mining Sciences

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2021

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Vol. 66, no. 2

279--295

EN

Gas explosions are major disasters in coal mining, and they typically cause a large number of deaths, injuries and property losses. An appropriate understanding of the effects of combustible gases on the characteristics of methane explosions is essential to prevent and control methane explosions. FLACS software was used to simulate an explosion of a mixture of CH4 and combustible gases (C2H4, C2H6, H2, and CO) at various mixing concentrations and different temperatures (25, 60, 100, 140 and 180℃). After adding combustible gases to methane at a constant volume and atmospheric pressure, the adiabatic flame temperature linearly increases as the initial temperature increases. Under stoichiometric conditions (9.5% CH4-air mixture), the addition of C2H4 and C2H6 has a greater effect on the adiabatic flame temperature of methane than H2 and CO at different initial temperatures. Under the fuel-lean CH4-air mixture (7% CH4-air mixture) and fuel-rich mixture (11% CH4-air mixture), the addition of H2 and CO has a greater effect on the adiabatic flame temperature of methane. In contrast, the addition of combustible gases negatively affected the maximum explosion pressure of the CH4-air mixture, exhibiting a linearly decreasing trend with increasing initial temperature. As the volume fraction of the mixed gas increases, the adiabatic flame temperature and maximum explosion pressure of the stoichiometric conditions increase. In contrast, under the fuel-rich mixture, the combustible gas slightly lowered the adiabatic flame temperature and the maximum explosion pressure. When the initial temperature was 140℃, the fuel consumption time was approximately 8-10 ms earlier than that at the initial temperature of 25℃. When the volume fraction of the combustible gas was 2.0%, the consumption time of fuel reduced by approximately 10 ms compared with that observed when the volume fraction of flammable gas was 0.4%.

10

Ultrasonic Assisted Active-Passive Filling Friction Stir Repairing to Eliminate Volume Defects

Wang Tao, Gong Xue, Ji Shude, Xue Gang, Lv Zan

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 1

217--222

EN

Ultrasonic assisted active-passive filling friction stir repairing (A-PFFSR) was proposed to repair volume defects in the metallic parts. Sound joints without interfacial defects could be achieved. Firstly, the ultrasonic was beneficial to improving material flow and atom diffusion, and then eliminated kissing bond defects compared to conventional A-PFFSR joints. Secondly, the equiaxed grains were refined by ultrasonic vibration. Lastly, the repairing passes were reduced due to the ultrasonic, which decreased softening degree of the repaired joints. The maximum tensile strength of 150 MPa was achieved. Therefore, this strategy to repair the volume defects is feasibility and potential in the remanufacturing fields of aerospace and transportation.

11

Analysis and experiments of embedded gripping mechanism used in large-scale tools holding up pile foundation in ocean

Wang Zhuo, Zhang Bo, Wang Tao

Polish Maritime Research

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2019

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nr 3

15--21

EN

With the rapid development of the marine economy and continuous improvement of the industry, the scale of the offshore engineering is increasing. This raises interest in studying, theoretically and experimentally, gripping and bearing mechanisms for large-scale holding and lifting tools used in foundation pile installations. In this paper, the embedded gripping mechanism is studied based on the theory of elastic-plastic mechanics. The embedded and bearing performance of the tooth is simulated and the influence factors are studied. In addition, the device used in the simplified embedded experiment on the tooth of the embedded block is designed. The relationship between embedded depth, load, and tooth profile angle is identified and validated. Meanwhile, the embedded performance of linear and ring type teeth is compared experimentally in order to select the suitable type of tooth for various situations. This comparison makes the basis for designing an upending gripper for the marine pile foundation, which can realize the operation of holding the pile to prevent its falling.

12

Low temperature preparation of stabilized aluminium titanate ultrafine powder assisted by the solvothermal treatment process

Zhang Quan, Liu Jianmin, Jiang Wei-Hui, Feng Guo, Jiang Feng, Wang Tao

Materiały Ceramiczne

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2019

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T. 71, nr 4

362--367

EN

Stabilized aluminium titanate (AT) ultrafine powder with the average particle size of 150 nm was prepared at 1000 °C assisted by the solvothermal process, using aluminium nitrate (Al(NO3)3•9H2O) and titanium tetrachloride (TiCl4) as precursor materials, ethanol as solvent, manganese(II) or iron(III) as stabilizer and PEG1000 as additive. The phase transition process of AT dry gel powder and the influence of technological parameters on the synthesis of stable AT superfine powder were studied by DTA-TG, XRD and TEM. The results showed that the amorphous dry gel formed anatase phase first, and then transformed into Al2(1-x)MgxTi1+xO5 solid solution. Magnesium acetate shows better stabilization effect compared with ferric chloride and ferric sulfate. Optimized dosages of magnesium acetate and PEG1000 are 10 mol% and 3 wt%, respectively.

PL

Stabilizowany, bardzo drobny proszek tytanianu glinu (AT) o średniej wielkości cząstek 150 nm został przygotowany w 1000 ° C przy pomocy procesu solwotermalnego, przy użyciu azotanu glinu (Al(NO3)3•9H2O) i czterochlorku tytanu (TiCl4) jako materiałów prekursorowych, etanolu jako rozpuszczalnika, mangan(II) lub żelazo(III) jako stabilizatorów i PEG1000 jako dodatku. Proces przemiany fazowej suchego proszku żelu AT i wpływ parametrów technologicznych na syntezę stabilnego super drobnego proszku AT zbadano za pomocą DTA-TG, XRD i TEM. Wyniki wykazały, że amorficzny suchy żel najpierw utworzył fazę anatazową, a następnie przekształcił się w stały roztwór Al2(1-x)MgxTi1+xO5. Octan magnezu wykazuje lepszy efekt stabilizujący w porównaniu z chlorkiem żelazowym i siarczanem żelazowym. Zoptymalizowane dawki octanu magnezu i PEG1000 wynoszą odpowiednio 10% mol. i 3% wag.

13

An improved UPLC method for determining uric acid in rat serum and comparison study with commercial colorimetric kits

Wen Shaoshi, Zhang Zixin, Chen Xiaopeng, Liu Jinchang, Yu Haiyang, Han Lifeng, Jin Lijun, Zhang Yi, Wang Tao

Acta Chromatographica

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2019

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Vol. 31, no. 3

201--205

EN

Uric acid (UA) is the final product of purine metabolism in humans. Elevated serum UA levels lead to the development of hyperuricemia, gout, kidney diseases, and metabolic syndrome. Accurate determination of UA plays a critical role in clinical diagnosis and laboratory investigation. An ultra-performance liquid chromatography (UPLC) with ultraviolet detection method has been developed and validated for UA analysis. Separation was achieved by a Waters ethylene bridged hybrid (BEH) Amide column (50 mm × 2.1 mm i.d., 1.7 μm) with acetonitrile and 0.1% acetic acid in deionized water in the proportion of 90 to 10 (v/v) as the mobile phase. The limit of detection and limit of quantification were 0.09 and 0.18 μmol/L, respectively. The method was validated by evaluating recovery (98.37–104.20%), accuracy (0.47–0.90%), and precision (1.24–1.81% for intra-batch and 1.76–3.98% for inter-batch). This method was then applied to UA determination in rat serum of hyperuricemia model. The results from UPLC, high-performance liquid chromatography (HPLC), and uric acid kits (phosphor-tungstic acid-based kit and uricase-based kit) were compared. The UPLC results were in very good agreement with HPLC. The developed method could be employed as a useful tool for the determination of UA in biofluids.