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1.
Sensors (Basel) ; 24(12)2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38931727

ABSTRACT

In recent years, underwater wireless ultrasonic energy transmission technology (UWUET) has attracted much attention because it utilizes the propagation characteristics of ultrasound in water. Effectively evaluating the performance of underwater ultrasonic wireless energy transmission is a key issue in engineering design. The current approach to performance evaluation is usually based on the system energy transfer efficiency as the main criterion, but this criterion mainly considers the overall energy conversion efficiency between the transmitting end and the receiving end, without an in-depth analysis of the characteristics of the distribution of the underwater acoustic field and the energy loss that occurs during the propagation of acoustic waves. In addition, existing methods focusing on acoustic field analysis tend to concentrate on a single parameter, ignoring the dynamic distribution of acoustic energy in complex aquatic environments, as well as the effects of changes in the underwater environment on acoustic propagation, such as spatial variability in temperature and salinity. These limitations reduce the usefulness and accuracy of models in complex marine environments, which in turn reduces the efficiency of acoustic energy management and optimization. To solve these problems, this study proposes a method to evaluate the performance of underwater ultrasonic energy radiation based on the spatial distribution characteristics of acoustic power. By establishing an acoustic power distribution model in a complex impedance-density aqueous medium and combining numerical simulation and experimental validation, this paper explores the spatial variation of acoustic power and its impact on the energy transfer efficiency in depth. Using high-resolution spatial distribution data and actual environmental parameters, the method significantly improves the accuracy of the assessment and the adaptability of the model in complex underwater environments. The results show that, compared with the traditional method, this method performs better in terms of the accuracy of the acoustic energy radiation calculation results, and is able to reflect the energy distribution and spatial heterogeneity of the acoustic source more comprehensively, which provides an important theoretical basis and practical guidance for the optimal design and performance enhancement of the underwater ultrasonic wireless energy transmission system.

2.
Polymers (Basel) ; 15(15)2023 Jul 25.
Article in English | MEDLINE | ID: mdl-37571049

ABSTRACT

Air pollution is related to the development of the national economy and people's livelihoods. Formaldehyde, as one of the main pollutants in the air, affects people's physical and mental health. In order to remove formaldehyde and better protect the health of residents, it is necessary to develop efficient adsorption materials. In this study, APMDS-modified cellulose composite aerogel microcrystalline was investigated. The adsorption of formaldehyde by the MCC/APMDS (Microcrystalline Cellulose/N-(2-aminoethyl)-3- Aminopropyl Methyl Dimethoxysilane) composite aerogel mainly relied upon the reaction of the protonated -NH3+ group in APMDS with formaldehyde to form a Schiff base to achieve the effect of deformaldehyde. Meanwhile, the modification of the aerogel reduced the pore volume and specific surface area, and the average pore size increased to 14.56 nm, which enhanced the adsorption capacity of formaldehyde, and the adsorption amount reached 9.52 mg/g. This study provides valuable information for the preparation of adsorbent materials with high formaldehyde adsorption capacity for air purification.

3.
Opt Express ; 30(16): 28614-28631, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-36299053

ABSTRACT

With the rapid development of light detection and ranging (LiDAR) technology, multispectral LiDAR (MSL) can realize three-dimensional (3D) imaging of the ground object by acquiring rich spectral information. Although color restoration has been achieved on the basis of the full-waveform data of MSL, further improvement of the visual effect of color point clouds still faces many challenges. In this paper, a highlight removal method for MSL color point clouds is proposed to explore the potential of 3D visualization. First, the MSL reflection model are introduced according to radar equation and Phong model, and the restored color of the MSL point clouds is determined to comprise diffuse and specular components. Second, a data conversion method is proposed to improve the massive point cloud processing efficiency by spatial dimension reduction and data compression. Then, the visual saliency map after color denoising is used to obtain the highlight region, the unknown information of which is recovered based on the global or local color information. Finally, three representative targets are selected and evaluated by qualitative and quantitative validation, which verifies that the method can effectively recover the high-quality highlight-free point clouds of MSL.

4.
Water Sci Technol ; 85(9): 2710-2721, 2022 May.
Article in English | MEDLINE | ID: mdl-35576263

ABSTRACT

Water-saving scientifically proved measures are crucial to reduce the use of decreasing fresh water resources. In this study, we investigate the current situation of residents' domestic water use, analyze the current situation of residents' water-saving measures, the current situation of residents' water-saving consciousness and its influencing factors. We performed a questionnaire survey and data obtained by relevant water supply departments, this paper used SPSS 19.0 and Excel 2020 software to conduct statistical analysis of survey data. Our results show that: (1) overall, the water consumption of urban residents in the central plains suburb is 18% higher than that of the original urban residents. (2) Among the residential water structures, washing, washing clothes and flushing toilets are the most frequent tasks, accounting for 87.3% of the total water consumption. (3) The implementation of water-saving measures by the original urban residents is better than that of the original suburban residents. (4) It is necessary to increase effective water-saving facilities and measures for urban water use.


Subject(s)
Urbanization , Water , China , Cities , Water Resources , Water Supply
5.
Lab Chip ; 19(3): 387-393, 2019 01 29.
Article in English | MEDLINE | ID: mdl-30648172

ABSTRACT

The biophysical properties of cells such as their compressibility have been found to be closely related to disease progression such as cancer development and metastasis. As cancer cells are heterogeneous, rapid and high-throughput evaluation of cell biophysical properties at single-cell resolution is needed to assess their potential as biomarkers for cancer staging and prognosis. Acoustofluidics has shown promise as a contactless method for accurately measuring cell biophysical properties; however, previously reported methods had relatively low throughput due to their requirement of no-flow conditions. This work presents a high-throughput continuous flow-based acoustofluidic cell mechanotyping method at single-cell resolution that retains the advantage of simplicity and low-cost.


Subject(s)
Acoustics , Flow Cytometry/instrumentation , Mechanical Phenomena , Single-Cell Analysis/instrumentation , Biomechanical Phenomena , Cell Line, Tumor , Humans
6.
J Acoust Soc Am ; 139(1): 332-49, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26827029

ABSTRACT

A numerical modeling method for accurately predicting the acoustophoretic motion of compressible microparticles in microfluidic devices is presented to consider the effects of fluid medium flow and spatial temperature variation that can significantly influence the acoustophoretic motion. In the proposed method, zeroth-order fluid medium flow and temperature, and first- and second-order acoustic fields in the microfluidic devices are first calculated by applying quadratic mapping functions and a second-order finite difference method (FDM) to perturbed mass, momentum, and energy conservation equations and state equation. Then, the acoustic radiation force is obtained based on the Gorkov's acoustic radiation force equation and applied to the Newton's Equation of Motion to calculate the microparticle motion. The proposed method was validated by comparing its results to a commercial software package, COMSOL Multiphysics results, one-dimensional, analytical modeling results, and experimental results. It is shown that the fluid medium flow affects the acoustic radiation force and streaming significantly, resulting in the acoustic radiation force and streaming prediction errors of 10.9% and 67.4%, respectively, when the fluid medium flow speed is increased from 0 to 1 m/s. A local temperature elevation from 20 °C to 22 °C also results in the prediction errors of 88.4% and 73.4%.

7.
Lab Chip ; 14(5): 947-56, 2014 Mar 07.
Article in English | MEDLINE | ID: mdl-24402640

ABSTRACT

Detecting and quantifying extremely low concentrations of oil from the environment have broad applications in oil spill monitoring in ocean and coastal areas as well as in oil leakage monitoring on land. Currently available methods for low-concentration oil detection are bulky or costly with limited sensitivities. Thus they are difficult to be used as portable and field-deployable detectors in the case of oil spills or for monitoring the long-term effects of dispersed oil on marine and coastal ecosystems. Here, we present a low-concentration oil droplet trapping and detection microfluidic system based on the acoustophoresis phenomenon where oil droplets in water having a negative acoustic contrast factor move towards acoustic pressure anti-nodes. By trapping oil droplets from water samples flowing through a microfluidic channel, even very low concentrations of oil droplets can be concentrated to a detectable level for further analyses, which is a significant improvement over currently available oil detection systems. Oil droplets in water were successfully trapped and accumulated in a circular acoustophoretic trapping chamber of the microfluidic device and detected using a custom-built compact fluorescent detector based on the natural fluorescence of the trapped crude oil droplets. After the on-line detection, crude oil droplets released from the trapping chamber were successfully separated into a collection outlet by acoustophoretic force for further off-chip analyses. The developed microfluidic system provides a new way of trapping, detecting, and separating low-concentration crude oil from environmental water samples and holds promise as a low-cost field-deployable oil detector with extremely high sensitivity. The microfluidic system and operation principle are expected to be utilized in a wide range of applications where separating, concentrating, and detecting small particles having a negative acoustic contrast factor are required.


Subject(s)
Microfluidic Analytical Techniques/methods , Oils/analysis , Dimethylpolysiloxanes/chemistry , Fluorescent Dyes/chemistry , Microfluidic Analytical Techniques/instrumentation , Oils/isolation & purification , Sound , Spectrometry, Fluorescence , Water/chemistry
8.
Biotechnol Biotechnol Equip ; 28(1): 140-146, 2014 Jan 02.
Article in English | MEDLINE | ID: mdl-26019500

ABSTRACT

NaoShuanTong capsule (NSTC), an oral traditional Chinese medicine formula, is composed of Pollen Typhae, Radix Paeoniae Rubra, Rhizoma Gastrodiae, Radix Rhapontici and Radix Curcumae. It has been widely used to treat ischemic stroke in clinic for many years in China. In addition to neuronal apoptosis, haemorheology and cerebral energy metabolism disorders also play an important role in the pathogenesis and development of ischemic stroke. The present study was designed to evaluate the in vivo protective effects of NSTC on haemorheology and cerebral energy metabolism disorders in rats with blood stasis. Sixty specific pathogen-free sprague-dawley rats, male only, were randomly divided into six groups (control group, model group, aspirin (100 mg/kg/d) group, NSTC low-dose (400 mg/kg/d) group, NSTC intermediate-dose (800 mg/kg/d) group, NSTC high-dose (1600 mg/kg/d) group) with 10 animals in each. The rats except those in the control group were placed in ice-cold water (0-4 °C) for 5 min during the time interval (4 h) of two adrenaline hydrochloride injections (0.8 mg/kg) to induce blood stasis. After treatment, whole blood viscosity at three shear rates, plasma viscosity and erythrocyte sedimentation rate significantly decreased in NSTC intermediate- and high-dose groups; erythrocyte aggregation index and red corpuscle electrophoresis index significantly decreased in all the three dose NSTC groups. Moreover, treatment with high-dose NSTC could significantly improve Na+-K+ adenosine triphosphatase (ATPase) and Ca2+ ATPase activity, as well as lower lactic acid level in brain tissues. These results demonstrated the protective effects of NSTC on haemorheology and cerebral energy metabolism disorders, which may provide scientific information for the further understanding of mechanism(s) of NSTC as a clinical treatment for ischemic stroke. Furthermore, the protective effects of activating blood circulation as observed in this study might create valuable insight for the utilisation of NSTC to be a feasible alternative therapeutic agent for patients with blood stasis.

9.
Zhong Yao Cai ; 35(11): 1854-8, 2012 Nov.
Article in Chinese | MEDLINE | ID: mdl-23627102

ABSTRACT

OBJECTIVE: To establish the HPLC fingerprint of Compound Xueshuantong Capsule. METHODS: Dionex Acclaim 120 C18 column (4.6 mm x 150 mm, 3 microm) was used with acetonitrile (A) and 0.05% phosphoric acid (B) in gradient elution mode. The elution profile was:0-50 min (15%-->34% A), 50-95 min (34%-->75% A); The detective wavelength was 203 nm and 270 nm. The column temperature was set at 25 degrees C and the flow rate was 1.0 mL/min. RESULTS: In the established fingerprint,42 common peaks covering 4 medicinal materials were detected, and 23 chemical compounds were identified by RRLC/MS/MS and DAD spetra. CONCLUSION: The method can be used for quality control of Compound Xueshuantong Capsule with great precision, accuracy and good reproducibility.


Subject(s)
Chromatography, High Pressure Liquid/methods , Drugs, Chinese Herbal/chemistry , Plants, Medicinal/chemistry , Abietanes/analysis , Capsules , Drugs, Chinese Herbal/analysis , Panax notoginseng/chemistry , Quality Control , Reproducibility of Results , Salvia miltiorrhiza/chemistry , Saponins/analysis
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