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1.
BMC Med Imaging ; 24(1): 131, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38840059

ABSTRACT

PURPOSE: To evaluate the intracavity left ventricular (LV) blood flow kinetic energy (KE) parameters using four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) in patients with acute myocardial infarction (AMI). METHODS: Thirty AMI patients and twenty controls were examined via CMR, which included cine imaging, late gadolinium enhancement (LGE) and global heart 4D flow imaging. The KE parameters were indexed to LV end-diastolic volume (EDV) to obtain average, systolic and diastolic KE as well as the proportion of LV in-plane KE (%). These parameters were compared between the AMI patients and controls and between the two subgroups. RESULTS: Analysis of the LV blood flow KE parameters at different levels of the LV cavity and in different segments of the same level showed that the basal level had the highest blood flow KE while the apical level had the lowest in the control group. There were no significant differences in diastolic KE, systolic in-plane KE and diastolic in-plane KE between the anterior wall and posterior wall (p > 0.05), only the systolic KE had a significant difference between them (p < 0.05). Compared with those in the control group, the average (10.7 ± 3.3 µJ/mL vs. 14.7 ± 3.6 µJ/mL, p < 0.001), systolic (14.6 ± 5.1 µJ/mL vs. 18.9 ± 3.9 µJ/mL, p = 0.003) and diastolic KE (7.9 ± 2.5 µJ/mL vs. 10.6 ± 3.8 µJ/mL, p = 0.018) were significantly lower in the AMI group. The average KE in the infarct segment was lower than that in the noninfarct segment in the AMI group (49.5 ± 18.7 µJ/mL vs. 126.3 ± 50.7 µJ/mL, p < 0.001), while the proportion of systolic in-plane KE increased significantly (61.8%±11.5 vs. 42.9%±14.4, p = 0.001). CONCLUSION: The 4D Flow MRI technique can be used to quantitatively evaluate LV regional hemodynamic parameters. There were differences in the KE parameters of LV blood flow at different levels and in different segments of the same level in healthy people. In AMI patients, the average KE of the infarct segment decreased, while the proportion of systolic in-plane KE significantly increased.


Subject(s)
Heart Ventricles , Myocardial Infarction , Humans , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/physiopathology , Male , Female , Middle Aged , Aged , Heart Ventricles/diagnostic imaging , Heart Ventricles/physiopathology , Case-Control Studies , Magnetic Resonance Imaging, Cine/methods , Blood Flow Velocity , Adult
2.
Cerebrovasc Dis ; 2023 Sep 18.
Article in English | MEDLINE | ID: mdl-37722371

ABSTRACT

INTRODUCTION: Moyamoya disease (MMD) is a vascular disease with significant risk of mortality due to ischemia or hemorrhage in the brain. The goal of the study was to explore three-dimensional arterial spin labeling (3D-ASL) to improve evaluation of cerebral hemodynamics in patients with MMD. METHODS: Our study included 54 cases of ischemic MMD and 42 cases of hemorrhagic MMD. Dynamic susceptibility contrast-enhanced perfusion weighted imaging (DSC-PWI) and 3D-ASL were performed at 3.0 T. Based on these scans, cerebral blood flow (CBF), mean transit time (MTT) and time to peak (TTP) were calculated and compared between patients with different disease subtypes. Receiver operating characteristics (ROC) analysis was used to assess the diagnostic sensitivity and specificity of different imaging procedures and parameters. RESULTS: Our data suggested that CBF in the lesion area was more severely reduced in patients with hemorrhagic MMD than in those with ischemic MMD. The CBF parameter in 3D-ASL diagnosed hemorrhagic and ischemic MMD with a significant sensitivity and specificity of 80.59% and 57.41% respectively, with an area under the curve (AUC) of 0.75. We also found that the relative CBF (rCBF) of 3D-ASL was more pronounced decreased and the relative MTT and TTP of DSC-PWI were significantly increased in patients with hemorrhagic MMD than those with ischemic MMD. Specificity and sensitivity, and AUC of 3D-ASL were better than the comparison of absolute values from DSC-PWI scans. DISCUSSION/CONCLUSION: Our study indicated that 3D-ASL is powerful in differentiating patients with cerebral ischemic or hemorrhagic MMD, providing another diagnostic tool that could potentially improve precision medicine to monitoring MMD patients.

3.
Nanoscale ; 15(34): 14249-14256, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37602367

ABSTRACT

All fluorescence white organic light-emitting diodes (WOLEDs) based on thermally activated delayed fluorescence (TADF) emitters are an attractive route to realize highly efficient and high color quality white light sources. However, harvesting triplet excitons in these devices remains a formidable challenge, particularly for WOLEDs involving conventional fluorescent emitters. Herein, we report a universal design strategy based on a co-host system and a cascaded exciton transfer configuration. The co-host system furnishes a broad and charge-balanced exciton generation zone, which simultaneously endows the devices with low efficiency roll-off and good color stability. A yellow TADF layer is put forward as an intermediate sensitizer layer between the blue TADF light-emitting layer (EML) and the red fluorescence EML, which not only constructs an efficient cascaded Förster energy transfer route but also blocks the triplet exciton loss channel through Dexter energy transfer. With the proposed design strategy, three-color all fluorescence WOLEDs reach a maximum external quantum efficiency (EQE) of 22.4% with a remarkable color rendering index (CRI) of 92 and CIE coordinates of (0.37, 0.40). Detailed optical simulation confirms the high exciton utilization efficiency. Finally, by introducing an efficient blue emitter 5Cz-TRZ, a maximum EQE of 30.1% is achieved with CIE coordinates of (0.42, 0.42) and a CRI of 84 at 1000 cd m-2. These outstanding results demonstrate the great potential of all fluorescence WOLEDs in solid-state lighting and display panels.

4.
Int J Hyperthermia ; 40(1): 2228519, 2023.
Article in English | MEDLINE | ID: mdl-37429585

ABSTRACT

OBJECTIVE: To investigate the feasibility and efficacy of real-time 3.0 T magnetic resonance imaging (MRI) guided percutaneous microwave ablation (MWA) in the treatment of multifocal liver cancer. METHODS: A total of 76 lesions in 26 patients with multifocal liver cancer who underwent 3.0 T MRI-guided microwave ablation in our hospital from April 2020 to April 2022 were retrospectively analyzed. The technical success rate, average operation time, average ablation time, and complications were evaluated. The upper abdomen was reviewed by pre- and post-contrast enhanced MRI scan every 1 months after the operation. The short-term curative effect was evaluated according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST) criteria (2020 version), and the local control rate was calculated. RESULTS: All 76 lesions were successfully operated. The technical success rate was 100%, the average operation time was 103.58 ± 18.57 min, the average ablation time of a single lesion was 11.00 ± 4.05 min, and the average ablation power was 43.03 ± 4.45 W. There were no serious complications such as massive bleeding, liver failure, and infection after the operation, except in one case with a small amount of pleural effusion and one case with right upper abdominal pain. The average follow-up time was 13.88 ± 6.62 months. One patient died due to liver failure, and one lesion developed a local recurrence. The local control rate was 98.7%. CONCLUSIONS: MWA of multifocal liver cancer guided by real-time 3.0 T MRI is a safe and feasible technique and has excellent short-term efficacy.


Subject(s)
Catheter Ablation , Liver Failure , Liver Neoplasms , Humans , Microwaves/therapeutic use , Retrospective Studies , Treatment Outcome , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/surgery , Liver Neoplasms/pathology , Magnetic Resonance Imaging/methods , Liver Failure/surgery , Catheter Ablation/methods
5.
IEEE J Biomed Health Inform ; 27(9): 4433-4443, 2023 09.
Article in English | MEDLINE | ID: mdl-37310831

ABSTRACT

Automated classification of lymph node metastasis (LNM) plays an important role in the diagnosis and prognosis. However, it is very challenging to achieve satisfactory performance in LNM classification, because both the morphology and spatial distribution of tumor regions should be taken into account. To address this problem, this article proposes a two-stage dMIL-Transformer framework, which integrates both the morphological and spatial information of the tumor regions based on the theory of multiple instance learning (MIL). In the first stage, a double Max-Min MIL (dMIL) strategy is devised to select the suspected top-K positive instances from each input histopathology image, which contains tens of thousands of patches (primarily negative). The dMIL strategy enables a better decision boundary for selecting the critical instances compared with other methods. In the second stage, a Transformer-based MIL aggregator is designed to integrate all the morphological and spatial information of the selected instances from the first stage. The self-attention mechanism is further employed to characterize the correlation between different instances and learn the bag-level representation for predicting the LNM category. The proposed dMIL-Transformer can effectively deal with the thorny classification in LNM with great visualization and interpretability. We conduct various experiments over three LNM datasets, and achieve 1.79%-7.50% performance improvement compared with other state-of-the-art methods.


Subject(s)
Lymphatic Metastasis , Machine Learning , Humans
6.
Int J Cardiovasc Imaging ; 39(3): 651-657, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36460876

ABSTRACT

The purpose of this article is to investigate the value of cardiac magnetic resonance imaging (CMR) derived left ventricular strain parameters in evaluation of ischemic cardiomyopathy (ICM). Thirty-one ICM patients and nineteen non-cardiomyopathy (non-CM) patients who performed CMR examinations during the same period were selected for this retrospective study. The basic clinical data, CMR left ventricular function parameters, left ventricular strain parameters were compared among the left ventricular ejection fraction (LVEF) preserved ICM group, the LVEF impaired ICM group and the non-CM group. The differences of MyoGCS (-21.9 ± 1.9 vs. -18.9 ± 2.7 P<0.001), MyoGLS (-20.8 ± 2.3 vs. -17.0 ± 2.9 P<0.001) and EndoGLS (-22.2 ± 3.1 vs. -17.6 ± 3.7 P<0.001) between LVEF preserved ICM group and non-CM group were statistically significant, while the differences of left heart function parameters between the two groups were not statistically significant (P > 0.05). The left ventricular strain analysis can be used to assess cardiac functional and morphological alterations in ICM patients prior to changes of left ventricular function parameters, which has high clinical significance.


Subject(s)
Cardiomyopathies , Humans , Stroke Volume , Ventricular Function, Left , Retrospective Studies , Predictive Value of Tests , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging, Cine
7.
Nanomaterials (Basel) ; 12(17)2022 Aug 30.
Article in English | MEDLINE | ID: mdl-36080031

ABSTRACT

Electrochemical energy storage devices (EESDs) have caused widespread concern, ascribed to the increasing depletion of traditional fossil energy and environmental pollution. In recent years, nickel cobalt bimetallic sulfides have been regarded as the most attractive electrode materials for super-performance EESDs due to their relatively low cost and multiple electrochemical reaction sites. In this work, NiCo-bimetallic sulfide NixCo3-xS4 particles were synthesized in a mixed solvent system with different proportion of Ni and Co salts added. In order to improve the electrochemical performance of optimized Ni2.5Co0.5S4 electrode, the Ni2.5Co0.5S4 particles were annealed at 350 °C for 60 min (denoted as Ni2.5Co0.5S4-350), and the capacity and rate performance of Ni2.5Co0.5S4-350 was greatly improved. An aqueous NiCo-Zn battery was assembled by utilizing Ni2.5Co0.5S4-350 pressed onto Ni form as cathode and commercial Zn sheet as anode. The NiCo-Zn battery based on Ni2.5Co0.5S4-350 cathode electrode delivers a high specific capacity of 232 mAh g-1 at 1 A g-1 and satisfactory cycling performance (65% capacity retention after 1000 repeated cycles at 8 A g-1). The as-assembled NiCo-Zn battery deliver a high specific energy of 394.6 Wh kg-1 and long-term cycling ability. The results suggest that Ni2.5Co0.5S4-350 electrode has possible applications in the field of alkaline aqueous rechargeable electrochemical energy storage devices for supercapacitor and NiCo-Zn battery.

8.
Cancer Manag Res ; 14: 1303-1312, 2022.
Article in English | MEDLINE | ID: mdl-35386184

ABSTRACT

Background: Paclitaxel (PTX) is an important oncologic chemotherapeutic agent against breast cancer, but breast cancer patients develop significant resistance to PTX during chemotherapy. Alterations in tubulin and associated proteins have been implicated in resistance to PTX. High-intensity focused ultrasound (HIFU) induces deep tumor penetration of anti-tumor agents in solid tumors. Methods: We investigated the influence of HIFU on the anti-tumor activities of PTX in breast cancer. Both in vivo and in vitro experiments were performed in this research: mice were treated with 2 mg/Kg PTX through tail vein injection, while breast cancer cells were treated with 400 nM PTX. Cell viability was analyzed through Cell Counting Kit-8. Cell apoptosis was evaluated through Annexin-V/PI Apoptosis Analysis Kit. The activities of catalase (CAT) and superoxide dismutase (SOD) and the concentration of malondialdehyde (MDA) were evaluated by relative commercial kits. Results: HIFU enhanced PTX-inhibited breast cancer cell viability and PTX-induced cell apoptosis. Simultaneous treatment of HIFU and PTX decreased the activities of CAT and SOD and increased the concentration of MDA. In mice bearing MDA-MB-231 tumors, the treatment of HIFU and PTX significantly decreased tumor size, increased body weight and elevated animal survival. HIFU enhanced the distribution of PTX in tumor tissues. Conclusion: The performance of HIFU promoted the distribution of PTX and enhanced its anti-tumor activities in breast cancer.

9.
Zhonghua Nan Ke Xue ; 28(10): 886-890, 2022 Oct.
Article in Chinese | MEDLINE | ID: mdl-37838954

ABSTRACT

OBJECTIVE: To study the effect of the bladder wall neourethra (BWN) technique on early urinary continence after laparoscopic radical prostatectomy (LRP). METHODS: We prospectively selected 40 cases of LRP performed in our hospital from August 2020 to August 2021 and randomly divided them into a BWN group (n = 20) and a control group (n = 20). We recorded the urinary continence rate of the two groups of patients at 7, 30, 90 and 180 days, and measured the maximum urethral pressure (MUP), functional urethral length (FUL) and functional urethral area (UFA) and observed the shape of the neourethra closure by MRI at 1 month after catheter removal. RESULTS: The urinary continence rates were significantly higher in the BWN than in the control group at 7 days (90.0% vs 25.0%, P < 0.001), 30 days (95.0% vs 35.0%, P < 0.001), 90 days (100% vs 60.0%, P < 0.05) and 180 days (100% vs 90.0%, P > 0.05) after catheter removal. No statistically significant difference was observed in MUP between the two groups (P > 0.05). FUL and FUA were remarkably higher in the BWN than in the control group (P < 0.01). MRI showed tight closure of the neourethra in the BWN group in the urine storage period. CONCLUSION: The BWN technique can significantly prolong FUL and improve early urinary continence after LRP.


Subject(s)
Laparoscopy , Urinary Incontinence , Male , Humans , Urinary Bladder/surgery , Urinary Incontinence/prevention & control , Urinary Incontinence/surgery , Prostatectomy/adverse effects , Prostatectomy/methods , Urethra/surgery , Laparoscopy/methods , Recovery of Function
10.
Materials (Basel) ; 14(20)2021 Oct 10.
Article in English | MEDLINE | ID: mdl-34683544

ABSTRACT

Infrared (IR) microlens arrays (MLA) have attracted increasing interest for use in infrared micro-optical devices and systems. However, the beam homogenization of IR laser light is relatively difficult to achieve because most materials absorb strongly in the IR wavelength band. In this paper, we present a new method for the application of double-sided quasi-periodic chalcogenide glass (ChG) MLAs to infrared laser homogenization systems. These are non-regular arrays of closely spaced MLAs. The double-sided MLAs were successfully prepared on the ChG surface using a single-pulse femtosecond laser-assisted chemical etching technique and a precision glass molding technique. More than two million close-packed microlenses on the ChG surface were successfully fabricated within 200 min. By taking advantage of ChG's good optical performance and transmittance (60%) in the infrared wavelength band (1~11 µm), the homogenization of the IR beam was successfully achieved using the ChG quasi-periodic MLA.

11.
Micromachines (Basel) ; 12(4)2021 Apr 19.
Article in English | MEDLINE | ID: mdl-33921624

ABSTRACT

A rapid and single-step method for the fabrication of a zinc selenide (ZnSe) concave microlens array through the high-speed line-scanning of a femtosecond laser pulse is presented. Approximately 1.1 million microlenses, with minimized volume and high transparency at wavelengths between approximately 0.76-20 µm were fabricated within 36 min. More importantly, the size of the microlenses can be controlled by adjusting the laser power. Their high-quality infrared optical performance was also demonstrated. This method holds great promise for the development of ZnSe-based micro-optical devices.

12.
Sci Rep ; 11(1): 8521, 2021 04 19.
Article in English | MEDLINE | ID: mdl-33875726

ABSTRACT

We present here the three-dimensional (3D) visualization fused with ultrasound and to evaluate its clinical application effect preliminarily. One hundred and eighteen patients with renal calculi in our hospital from September 2017 to December 2019 were prospectively randomized into two groups. The experimental group was treated with percutaneous renal puncture guided by the 3D visualization fused with ultrasound. The control group was treated with percutaneous renal puncture guided by B-ultrasonography (B-US). The puncture time in the experimental versus control group was 4.36 ± 1.28 min versus 10.72 ± 2.94 min (P = 0.000), operation time was 65.85 ± 10.63 min versus 81.34 ± 12.52 min (P = 0.000), and the loss of hemoglobin was 8.55 ± 3.76 g/L min versus 13.33 ± 5.81 g/L(P = 0.000), and the success rate of establishing the channel at one time was 98.41% versus 81.82% (P = 0.002), and the coincidence rate between the channel and the longitudinal axis of the target renal calyx was 88.89% versus 60.00% (P = 0.000). The 3D visualization fused with ultrasound could guide precise puncture to target calyces, reduce operation time, bleeding, and difficulty of puncture.


Subject(s)
Imaging, Three-Dimensional/methods , Kidney Calculi/surgery , Punctures/methods , Ultrasonography/methods , Adult , Female , Humans , Kidney , Male , Prospective Studies , Ultrasonography, Interventional
13.
Chemosphere ; 276: 130139, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33690039

ABSTRACT

A kind of biosurfactant rhamnolipid modified zero-valent iron nanoparticles have been synthesized and applied to evaluate the immobilization efficiency of Ni (Ⅱ) contaminated soil at three concentration levels (200Ni, 600Ni and 1800Ni). The results of SEM and XRD were clearly indicative of the well-attached phenomenon of rhamnolipid on the nZVI, featuring better stability and dispersity, and FTIR analysis proposed the interactions between rhamnolipid and nZVI through monodentate chelating between carboxylate groups and nZVI or hydrogen bonding with Fe-O groups on the surface. Sequential extraction procedures (SEP) analysis illustrated that the majority of labile fractions had been transformed into less accessible fractions (Fe-Mn oxide-bound fractions and residual fractions) after 28 days of incubation. And for low-concentrations polluted soil, soil self-remediation played a dominant role, while RL@nZVI exhibited a more significant stabilizing effect for medium and high-concentrations pollution. Furthermore, XPS and XRD analyses of Ni-adsorbed RL@nZVI identified the formation of NiO, Ni(OH)2 and revealed the possible interaction mechanisms including reduction, adsorption and precipitation/co-precipitation. These results confirmed that RL@nZVI presented a promising prospect for the immobilization of Ni polluted soil.


Subject(s)
Environmental Restoration and Remediation , Soil Pollutants , Glycolipids , Iron , Soil , Soil Pollutants/analysis
14.
Environ Pollut ; 276: 116745, 2021 May 01.
Article in English | MEDLINE | ID: mdl-33640653

ABSTRACT

Nanoscale zero-valent iron (nZVI) modified by cationic polyquaternium-7 (M550-nZVI) or anionic carboxymethyl cellulose (CMC-nZVI) were freshly synthesized, and followed by the successful applicability for the stabilization of Cr(VI) in soil. Scanning electron microscope (SEM) showed that the sizes of M550-nZVI and CMC-nZVI were 42-170 nm and 66-200 nm, respectively. X-ray diffraction (XRD) confirmed the presence of Fe0 and Fe3C in the as-synthesized composites. The kinetics were well fitted with pseudo-second order model (R2 > 0.99), indicating that the process was principally chemical reduction. Additionally, we observed that M550-nZVI had better resistance to oxidation than that of CMC-nZVI. Besides, RSM experiments showed that acetate ion (AA) could promote the Cr(VI) removal but humic acid ion (HA) and carbonate ion (CA) resulted in negative effects. Moreover, the modeling predication revealed that the optimum Cr(VI) removal of 92.44% by CMC-nZVI was available, being 22.52% higher than that of M550-nZVI. In conclusion, this work demonstrated that the inoxidizability of M550-nZVI had a dominant advantage, while CMC-nZVI had the more excellent reactivity than M550-nZVI. We believe that our conducted research work will open the new avenues for effective removal of heavy metals from the soil.


Subject(s)
Iron , Water Pollutants, Chemical , Adsorption , Chromium/analysis , Kinetics , Polymers , Soil , Water Pollutants, Chemical/analysis
15.
Micromachines (Basel) ; 12(1)2021 Jan 01.
Article in English | MEDLINE | ID: mdl-33401435

ABSTRACT

Nested structures inside the hard material play a pivotal role in the microfluidics systems, such as the microvalve and the micropump. In this article, we demonstrate a novel and facile method of fabricating nested structures inside the fused silica with a two-step process femtosecond laser wet etching (FLWE) process. Inside fused silica, a spherical structure was made with a diameter of nearly 80 µm in a square chamber. In addition, we designed a simple microvalve with this sphere controlling the current's flow. The novel microvalve structure can be easily integrated into the functional microfluidics systems and will be widely applied in the Lab-on-chip (LOC) system.

16.
Front Chem ; 8: 575786, 2020.
Article in English | MEDLINE | ID: mdl-33134276

ABSTRACT

Microlens arrays (MLAs) and MLA-based artificial compound eyes (ACEs) are the important miniaturized optical components in modern micro-optical systems. However, their optical performance will seriously decline once they are wetted by water droplets (such as fog, dew, and rain droplets) or are polluted by contaminations in a humid environment. In this mini-review, we summarize the research works related to the fabrication of superwetting MLAs and ACEs and show how to integrate superhydrophobic and superoleophobic microstructures with an MLA. The fabrication strategy can be split into two categories. One is the hybrid pattern composed of the MLA domain and the superwetting domain. Another is the direct formation of superwetting nanostructures on the surface of the microlenses. The superhydrophobicity or superoleophobicity endows the MLAs and ACEs with liquid repellence and self-cleaning function besides excellent optical performance. We believe that the superwetting MLAs and ACEs will have significant applications in various optical systems that are often used in the humid or liquid environment.

17.
Opt Express ; 28(18): 25716-25722, 2020 Aug 31.
Article in English | MEDLINE | ID: mdl-32906856

ABSTRACT

Microfluidic chips have gradually become a focus of scientific research. However, the fabrication of key functional components in microfluidic chips is always limited by the existing processing methods. The microfluidic chip is difficult to be three-dimensional (3D) and integrated. In response to the key problems of 3D integrated microfluidic chip fabrication, this paper presents a hybrid method for fabricating a microfluidic chip integrated 3D microchannels and metal microstructures by femtosecond laser wet etch technology and liquid metal injection. The integrated microfluidic chip fabricated by this method is expected to be applied to the core reaction unit of integrated PCR devices.

18.
Materials (Basel) ; 13(16)2020 Aug 07.
Article in English | MEDLINE | ID: mdl-32784658

ABSTRACT

Chalcogenide glasses (ChGs) are emerging as critical infrared (IR)-enabled materials in advanced IR optical systems by the wealth of their transparency in the key wide infrared (IR) transmission window. However, fabrication of ChG-based integrated micro-optical components in an efficient and economical way remains a huge challenge. In this paper, a 3D close-packed hexagonal microlens array (MLA) possessing over 6000 convex hexagonal micro-lenslets with the size of tens of micrometers within a footprint of 10 mm × 10 mm on a Ge20Sb15Se65 ChG surface was successfully fabricated via a precise thermal-mechanical molding process. The master mold of ChG MLA was firstly fabricated by a femtosecond laser-assisted chemical etching process and then transferred on to the surface of the ChG via a precision thermo-mechanical molding process, which resulted in a convex MLA. The morphology, imaging and focusing performances of the as-prepared ChG MLA were investigated and demonstrated the advancement of the method. Meanwhile, the IR transmittance and x-ray diffraction image of the ChG MLAs were measured to verify the structural and compositional stability of the ChG under the given molding conditions. The combined results proved a new route to mass production of miniaturized gapless ChG MLAs for advanced infrared micro-optics.

19.
Front Chem ; 8: 507, 2020.
Article in English | MEDLINE | ID: mdl-32733843

ABSTRACT

The achievement of high-efficiency oil/water separation has huge implications for protecting environment and reducing economic losses, but there is still a great challenge. Currently, most artificial oil/water separating materials are fabricated through complex preparation process, resulting in the very high cost of separation. In this paper, we present a simple and low-cost method to achieve oil/water separation by using the underwater superoleophobic materials that already exist in our life or nature. Taking filter paper and zeolite layer as examples, we show the inherent porous microstructures of these materials. Such porous microstructures endow filter paper and zeolite layer with strong ability to absorb water and the underwater superoleophobicity. Based on the porous feature and underwater superoleophobicity, the pre-wetted filter paper and zeolite layer can be used to effectively separate the mixture of water and oil, with great separation capacity. The existing materials (e.g., filter paper and zeolite layer) with both porous microstructure and underwater superoleophobicity in our life or nature are green and low-cost, and can be easily obtained. Such advantages allow those materials to potentially solve the pollution problems caused by the discharge of industrial oily wastewater and the oil-spill accidents.

20.
Front Chem ; 8: 687, 2020.
Article in English | MEDLINE | ID: mdl-32850682

ABSTRACT

Underwater superoleophobic microlens array (MLA) has been emerging as a crucial device for its wide applications in ocean optical imaging and sensing, endoscopic surgery, microfluidics and optofluidics, and other biomedical applications. Fabrication of microlens arrays integrated with excellent optical performance as well as underwater superoleophobicity remains a great challenge. In this paper, we report an underwater super oil-repellent MLA on a transparent optical glass substrate via femtosecond laser-induced phase and structural modification and chemical isotropic etching. The fabricated sample simultaneously possesses microlens structures with a smooth surface to enable optical imaging function, and grid-patterned biomimetic micro/nano hierarchical surface structures to produce underwater oil-resistance with a contact angle of 160.0° and a sliding angle of 1.5°. The resultant oil-repellent MLA exhibits underwater superoleophobicity and self-cleaning abilities in water. Meanwhile, it was demonstrated to have impressive imaging capability even after oil contamination. We believe that this novel resultant anti-oil MLA will be helpful for underwater detection and bioscience research, especially in oil polluted underwater workspaces.

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