LAB ON A CHIP
·
2022
·Vol. 22
·期 18
·3412-3423
·
IF 7.517
Shilu Zhu,Weijie Zheng,Jian Wang,Xingmiao Fang,Lijiu Zhang,Fuzhou Niu,Ying Wang,Tingting Luo,Guangli Liu,Runhuai Yang
Microrobots have been extensively studied for biomedical applications, and significant innovations and advances have been made in diverse aspects of the field. However, most studies have been based on individual microrobots with limited capabilities, constraining their scalability of functions for practical use. Here, we demonstrate the interactive and synergistic behaviours of multiple microrobots that are heterogeneous or incompletely homogeneous. A frequency-response theory is proposed where in a certain frequency range of an external rotating magnetic field (RMF), microrobots with dispersed and linearly aligned magnetic nanoparticles (MNPs) would exhibit similar and different behaviour, respectively. These microrobots rotate following the rotation of the external field, and such complete rotational motion is interrupted when the frequency exceeds a certain value, called the critical frequency (cf), but such behaviour is more prominent in microrobots with linear MNPs. Upon further investigating the effect of various parameters on the cf of the microrobots during the fabrication process, we find that heterogeneous microrobots with specific cf values can be customized. In addition, experiments and simulations are combined to show the hydrodynamic behaviours around the rotating microrobots at different frequencies. Based on these findings, the interactive and synergistic behaviours of multiple microrobots are presented, which suggests great potential for the independent execution of multiple tasks or the synergistic performance of complex tasks and is significant for the future development of interactive synergistic microrobots in the biomedical field.
研究领域:
生物医学工程
·
纳米技术
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产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·Vol. 51
·期 28
·57045-57052
·
IF 5.6
Hongxi Chen,Cheng Liu,Junxiao Liu,Guocai Mu,Yongjie Zhou,Hengrui Wang,Dainan Zhang,Yuanxun Li,Huaiwu Zhang
In this study, phosphorus enriched LiMgP 1+ x O 4 (0.00 ≤ x ≤ 0.04) ceramics were synthesized via the solid-state reaction route. The crystal and phase structure patterns were analyzed by the Rietveld refinement and Raman spectroscopy. The dielectric properties were obtained at both microwave and terahertz frequencies. Optimal microwave dielectric performance was obtained in LiMgP 1.01 O 4 , sintered at 875 °C for 4 h: ε r = 6.964, Q × f = 82,057 GHz, and τ f = −27.1 ppm/°C (at 15.361 GHz). Compared with the pure LiMgPO 4 ceramics sintered at 950 °C ( Q × f = 79,100 GHz and τ f = −55 ppm/°C), an appropriate amount of excessive P 5+ reduced the sintering temperature while improving the Q × f value and the thermal stability effectively. Within the terahertz frequency range of 0.2–1.2 THz, the ε r values were decreased to 5.40–6.65 while the tan δ values were ranged from 0.0039 to 0.1228. All experimental results suggested that the LiMgP 1+ x O 4 ceramics are promising for both microwave and terahertz frequency applications.
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Qin Yu,Cheng Liu,Junxiao Liu,Da Huang,Tianlong Wen,Dainan Zhang,Huaiwu Zhang
In this study, NaMg 1- x Mn x (PO 3 ) 3 (0.00 ≤ x ≤ 0.0625) ceramics with low dielectric constant were prepared via the solid-state reaction method. The effects of Mn 2+ substitution on the microstructure and dielectric properties (at microwave and terahertz frequencies) of the NaMg(PO 3 ) 3 ceramics were studied by means of the Rietveld refinement, morphology, and ionic polarizability analysis. It is obtained that the NaMg 0.0975 Mn 0.025 (PO 3 ) 3 ceramic sintered at 880 °C for 4 h exhibited optimal dielectric properties at microwave frequencies, where ε r = 4.585, Q × f = 48,313 GHz (@17.228 GHz), and τ f = −40.83 ppm/°C. The Q × f and τ f values were changed by 74.2 % and 27.8 %, as compared to the values of 27,728 GHz and −56.52 ppm/°C for the pure NaMg(PO 3 ) 3 ceramic, respectively. For terahertz frequencies (0.2–1.0 THz), the ε r values were decreased to 3.79–3.98, and the tan δ values were between 0.0203 and 0.1152. All the experimental results indicate that this system exhibits great potentials both at microwave and terahertz frequencies.
研究领域:
材料科学
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电气工程
·
陶瓷
·
介电材料
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2022
·
IF 10.753
Hongyan Shen,Mingru Yang,Jing Wang,Xiaoming Zou,Danqing Tong,Yulian Zhang,Liang Tang,Haoyu Sun,Lei Yang
The judgment of joint resistance action is significant for evaluating the resistance risk of antibacterial mixture. Using bacterial mutation frequency ( MF ) and conjugative transfer frequency ( CTF ) to respectively characterize the bacterial endogenous and exogenous resistance, mutation unit and conjugative transfer unit have been proposed to judge the joint resistance action of antibacterial mixture at a certain dose. However, these methods could not evaluate the antibacterial mixture's joint resistance action at a larger concentration-range. In this study, the concentration addition for bacterial resistance ( CA-BR ) approach was used to judge the joint resistance actions between kanamycin sulfate (KAN) and some other typical antibacterial agents, including sulfonamides (SAs), sulfonamide potentiators (SAPs), and silver antibacterial compounds (SACs). Through comparing the hormetic dose-response curves of the binary mixtures on the MF (or CTF ) in Escherichia coli ( E. coli ) and the corresponding CA-BR curves calculated from the hormetic dose-responses of the single agents, the joint resistance actions between KAN and other agents were judged to exhibit dose-dependent feature: with the increase of mixture concentration, the joint mutation actions between KAN and SAs (or SAPs) were fixed at synergism, and the joint mutation actions between KAN and SACs varied from antagonism to synergism; the joint conjugative transfer actions between KAN and other agents changed from antagonism to synergism. Mechanistic explanation suggested that the heterogeneous pattern of joint resistance action had a close relationship with the interplays among the agents' modes of action, and meanwhile was significantly influenced by their joint survival pressure on E. coli . This study reveals the dose-dependent feature for the joint resistance action of antibacterial mixture and highlights the importance of exposure concentration, which will benefit clarifying the resistance risk of antibacterial mixture in the environment.
研究领域:
微生物学
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环境科学
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药理学
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产品关联
DOI
PubMed
高影响因子
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
·
2017
·Vol. 31
·期 12
·1031-1040
·
IF 1.998
Xinming Huo,Jin Chen,Fei Tang,Tongtong Yao,Shiyun Piao,Kai Ni,Xiaohao Wang
Rationale Secular frequency scanning is a mass spectrometry (MS) analysis method in which the frequency of the auxiliary alternating current (AC) signal is scanned. It has low requirements for radio-frequency (RF) power, which is beneficial for the miniaturization of the mass spectrometer. In this study, the MS performance in the reverse secular frequency scanning (RSFS) mode is optimized for a rectilinear ion trap (RIT), and a method for rapid MS analysis using continuous secular frequency scanning (CSFS) is proposed. Methods A RIT mass spectrometer with an auxiliary AC frequency scanning function was built. The resolution, tandem mass spectrometry (MS/MS) and quantitation capability in the RSFS mode were characterized and optimized. Operation in the CSFS mode was then performed by scanning the frequency of the auxiliary AC signal continuously and periodically while maintaining the RF signal and the front Z electrode in the ion injection state, so that the ion injection and cooling were performed at the same time as the mass analysis. Results With this system, the RSFS mode achieved unit mass resolution at 332 Th, and the MS/MS analysis was completed without changing the RF amplitude at q = 0.4583 for reserpine. The limit of quantitation for imatinib was about 250 ng/mL with the determination coefficient R 2 = 0.9981. In the CSFS mode, a single analysis cycle of less than 20 ms could be achieved, which is 14 times faster than the traditional sweep modes. In addition, 100% ion utilization can theoretically be achieved in the CSFS mode. Conclusions The CSFS mode is different from the traditional phased sequential operation mode of an ion trap mass spectrometer. By periodic scanning of the auxiliary AC frequency while maintaining ion injection, it is possible to improve the analysis efficiency of the mass spectrometer, which has the prospect of useful application in the field of rapid MS monitoring. Copyright © 2017 John Wiley & Sons, Ltd.
研究领域:
分析化学
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质谱学
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DOI
PubMed
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 42
·26211-26219
·
IF 3.108
Dandan Li,Lunan Guo,Na Yang,Yao Zhang,Zhengyu Jin,Xueming Xu
The properties and functionalities of chitosan are closely related to its degree of deacetylation (DD). This study aimed to determine the DD of chitosans, which were of identical molecular weight, by a proposed electro-analytical system based on inductive methodology. Statistically significant differences in electrical parameters, including terminal voltage (U′S) and λ (the ratio of primary voltage to U′S) were observed among chitosans with different DDs. Both U′S and λ were linearly correlated with the DD value, regardless of frequency, suggesting that these electrical parameters can be used to determine the DD of chitosan. More chitosan's coils contributed to higher measurement accuracy, but the change in measurement position showed no improvement. The highest linear coefficient of determination (0.9941) between DD and U′S was obtained by the experimental transformer with 100-turn chitosan's coils at a primary voltage of 10 V and a frequency of 400 Hz. This study explored the potential of an innovative electro-analytical system to determine the DD of chitosan.
研究领域:
生物化学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Food Measurement and Characterization
·
2018
·Vol. 12
·期 2
·1266-1273
·
IF 1.181
He Xueming,Fu Xiaping,Li Tingwei,Rao Xiuqin
A spatial frequency domain imaging system (SFDI) was developed to estimate the optical properties of biological samples. The system was calibrated by using a series of self-made solid phantoms which covering a wide range of absorption ( µ
a
) and reduced scattering coefficients ( \({\mu ^{\prime}_s}\) ). The relative errors between the reference and calibrated values were regarded as the evaluation parameters for validation effectiveness of the system, the results showed that the maximum relative errors of µ
a
and \({\mu ^{\prime}_s}\) are 3.92 and 2.39% respectively. Quantitative absorption and scattering maps at the wavelength of 527 nm were obtained for four kinds of pear samples (normal and bruised with three levels of bruised severity with impact energy of 0.025, 0.075 and 0.125 J). The normal pears could be distinguished from the bruised pears by comparing values of coefficient of variation ( CV ) of \({\mu ^{\prime}_s}\) maps, and the correct rates of the discriminant analysis were 100% for non-bruised pears,and 98.33% for bruised pears. Bruises induced using 0.025 J (class 1) were distinguishable from those induced using 0.075 and 0.125 J (class 2) by comparing ratio between mean values of bruised region and normal region of \({\mu ^{\prime}_s}\) maps, the results turned out that the class 1 had the correct rate of 90%, and class 2 had the correct rate of 87.5%. The research showed that SFDI has the potential to be used in the detection of bruises on ‘Crown’ pears and the proposed calibration method lay the foundation for future studies. Future work will be conducted with an emphasis on the acquisition of more spectral information, surface profile correction and the acceleration of detection speed.
研究领域:
生物医学光学
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食品质量检测
·
成像技术
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2024
·
IF 6.5
Jianguo Wu,Haoxiang Xu,Dong Cao,Daojian Cheng
Supported PdAu bimetallic nanoparticles have been developed for the direct synthesis of H 2 O 2 (DSHP). However, to date, the dilute H 2 streams necessary to avoid potential risks of explosion limits the attainable product concentrations of H 2 O 2 . Here, a series of silicon-modified Al 2 O 3 (Si x Al) were synthesized for loading PdAu bimetallic nanoparticles . The H 2 consumption turnover frequency (TOF) and H 2 O 2 formation TOF show a volcano trend with the silica content, where PdAu/Si 5.6 Al exhibits the best H 2 consumption TOF and H 2 O 2 formation TOF (11259.3 and 1995.2 h −1 ). Silica on the surface of Al 2 O 3 is identified as Brønsted (B) acid site. The increase of B acid sites density accelerates the H 2 conversion into H atoms, thereby boosting H 2 O 2 formation process. The adsorption and dissociation of H 2 into atomic H at B acid sites would spill across the support to PdAu nanoparticles reversely. The reversed hydrogen spillover effect induced by B acid site accounts for enhanced H 2 conversion and H 2 O 2 productivity for PdAu/Si x Al.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Manufacturing Processes
·
2024
·
IF 6.1
Zihao Li,Weiwei He,Yanzhen Zhang,Jide Wang,Guofang Hu,Yuyao Wu,Dege Li
The electrohydrodynamic (EHD) inkjet printing is rooted in the creep effect exhibited by fluid interfaces subjected to high-intensity electric fields. It utilizes the micro-jetting from the tip of the Taylor cone to print intricate patterns with sub-micron feature sizes. However, due to the limitations inherent in the jetting mechanism, the highest printing frequencies for conventional EHD are limited to several hundred Hertz. Here, we discover a novel phenomenon where the vibration of meniscus in an electric field can induce EHD jetting within microseconds, or even sub-microseconds. Based on this phenomenon, we propose a new method for achieving megahertz level EHD jetting based on meniscus vibrations (MVEHD). This paper systematically elucidates the fundamental mechanisms of the forced meniscus vibration, cone sharpening, and the jetting formation through a combination of experimental research and numerical simulation. Additionally, adjustable continues inkjet (CIJ) and drop on demand (DOD) inkjet printing modes were developed, demonstrating the potential of dual-mode technology in the development of automotive transparent glass heaters (TGHs) and Micro-LED displays. This method effectively elevates the efficiency of traditional EHD by 2 to 4 orders of magnitude, thereby laying a theoretical and technical foundation for the industrial application of high-throughput EHD technology.
研究领域:
材料科学
·
微纳米技术
·
印刷工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 107
·105338-105346
·
IF 3.289
Deyuan Xie,Ye Sun,Tianle Zhu,Xing Fan,Xiaowei Hong,Wenhao Yang
NH3 synthesis from H2O + N2, H2 + N2 or H2O + H2 + N2 by dielectric barrier discharge combined with an Ru/Al2O3 catalyst is studied at atmospheric pressure and room temperature. Additionally, the effects of reaction gas composition, energy density, and discharge frequency on NH3 yield and by-product formation are investigated. The results show that NH3 can be formed from reaction gases consisting of H2O and N2. The NH3 yield of the reaction gas containing H2 is much higher than that of the reaction gas consisting of H2O and N2. The presence of H2O has a promotion effect on NH3 synthesis from H2 and N2, especially for reaction gases with an H2 content less than 10%. The NH3 yield first increases and then decreases with an increase in the energy density. The maximum yield of 680 mg kW−1 h−1 occurs at the energy density of 1400 J L−1 and in the reaction gas of 0.14% H2O, 40% H2 and N2. The discharge frequency has a great effect on the NH3 yield, and maximum NH3 yield is obtained at the frequency of 13 kHz. Besides NH3, some by-products, such as N2O and NO2, are also formed with reaction gases containing H2O. However, their formation can be suppressed in the presence of H2, which is attributed to the reduction effect of H2 on the by-products.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY
·
2022
·
IF 5.062
Tingting Kang,Jinyi Zhao,Long Lin,Long Zhu,Zewei Zhao,Yao Huang,Xiaolong Gao,Jian Zhuang,Jingyao Sun,Daming Wu
The transdermal delivery effect of polymeric microneedles can be significantly improved with the aids of synergetic vibration. The finite element simulation software ANSYS was used to explore the skin puncturing results of microneedles under different vibration frequencies. The dynamic mechanical properties of polymeric microneedles and human skin were also investigated. Meanwhile, puncturing experiments were also performed under different vibration frequencies on abdomen of female mice using polymeric microneedles with different lengths. The results showed that the peak value of maximum equivalent stress and the plastic deformation of skin were the smallest at the vibrative frequency of 200 Hz. The maximum equivalent stresses presented 20%–50% decreases during the second puncturing cycle. Moreover, the puncturing result of longer microneedles (550 μm) is much better than that of shorter ones (350 μm) under the same vibration frequency. The average bottom diameter and penetration depth of the microchannel obtained under the conditions of 200 Hz vibration and 550 μm height microneedles were 671.03 and 367.55 μm, respectively. These results provided an experimental basis to verify the effectiveness of mechanical vibration for skin puncturing.
研究领域:
生物医学工程
·
药剂学
✓ 已验证
产品关联
DOI
高影响因子
Food Science and Technology
·
2022
·
IF 2.602
LIAO Jianqing,XUE Hongkun,LI Junling,PENG Ling
The aim of this work was to evaluate the effects of ultrasound frequencies from 18 to 90 kHz on the extraction of anthocyanin from strawberry fruit by using an approach of modified ultrasound-assisted extraction (MUAE) that was based on a frequency search device with six extraction tanks controlled by a computer. According to the obtained optimal frequency of 62-64 kHz, the effects of other different process variables, such as treatment time, temperature, ultrasound power and solvent to solid ratio, on the extraction of anthocyanin were also studied in comparison with heat assisted extraction (HAE) and ultrasound-assisted extraction (UAE). The obtained results showed that the maximum yield of 796.9 μg/g of anthocyanin was obtained at the optimized conditions of ultrasound frequency of 62-64 kHz, solvent to solid ratio of 6 mL/g, ultrasound power of 120 W, temperature of 45°C and treatment time of 12 min with 55% ethanol as the solvent. The application of MUAE showed that anthocyanin yield increased by about 42% and 22% higher than that of HAE and UAE, respectively. These findings demonstrated MUAE is not only an effective and feasible method for extracting anthocyanin from strawberry fruit, but also promising for extracting active components from natural materials in industry.
研究领域:
食品科学
·
植物化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）