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Thin-walled polystyrene (PS) spheres are needed for preparing the targets in the inertial confined fusion (ICF). To prevent the occurrence of craze and crack in the fabrication of the spheres, a noncovalent interaction route is developed to improve the mechanical properties of thin-walled polystyrene spheres based on a fullerene derivative, reducing the craze and crack yield. The introduction of phenyl-C61-butyric acid methyl ester (PCBM) into PS spheres not only improves the thermal stability, but also reduces the craze and crack yield, probably to the [pi]-[pi] interaction between PCBM and PS and the hydrophobicity of PCBM. The sphericity and surface finishing of the spheres also increase at the same time. Mechanism of how the PCBM improve the quality of the spheres is also discussed. Highlights * A noncovalent interaction route to improve properties of PS spheres is proposed. * PS/PCBM spheres with good quality are successfully designed and fabricated. * Mechanisms of how the PCBM improve properties of PS spheres are also discussed. KEYWORDS fullerene, inertial confined fusion, microfluidic technique, noncovalent interactions, polymer spheres, [pi]-[pi] interaction, 1 | INTRODUCTION Hollow polymer spheres show numerous applications in various fields such as food, medicine, and energy. For example, hollow polymer spheres can used as the containers of the [...]

Objective To investigate the effects of clearing meibomian gland ducts prior to cataract surgery on the gland dysfunction and dry eye induced by surgery. Methods A prospective, randomized controlled trial was conducted on 110 patients (110 eyes) undergoing elective cataract surgery for senile cataract in our department from June 1, to December 31, 2021. The participants were randomly allocated into treatment (n=56) and control (n=54) groups. The patients from the treatment group were given eyelid compresses and cleaning to remove an obstructed meibum in 1 week prior to cataract surgery, while those from the control group received no such treatment. Ocular surface disease index (OSDI), indicators related to meibomian gland function, including tear film lipid layer thickness (LLT), meibomian glands yielding liquid secretion (MGYLS), meibomian glands yielding secretion score (MGYSS), and tear film break-up time (TBUT) before, and 1 and 3 months after surgery were employed to evaluate the efficacy of clearing meibomian gland ducts. Results The control group exhibited significantly decreased MGYLS (P

Abstract Polymer microspheres can be used as fuel containers for laser inertial confinement fusion (ICF) due to their low atomic number, low density, and high thermal stability. The thin-walled polymer [...]

A new type of deuterated polymer microspheres with a much higher deuterium/carbon (D/C) atom ratio was designed and fabricated to produce high‐yield thermonuclear neutrons. Supramolecular deuterated polycyclooctene (D‐PCOE) with ~1.7 D/C atom ratio was synthesized, which well meets the requirements including higher D/C atom ratio, good solubility for processability, and excellent mechanical properties. Monodispersed D‐PCOE microspheres including shells and beads are fabricated by a microfluidic technique. The properties of the D‐PCOE materials and corresponding microspheres are analyzed and compared with those of the deuterated polystyrene microspheres (~1 D/C atom ratio), which have been widely used in laser‐driven spherically convergent plasma fusion experiments. This work expands the category of deuterated polymeric materials and provides a new type of deuterated polymer microspheres in the forthcoming high‐yield neutron experiments. Highlights: Supramolecular D‐PCOE with ~1.7 D/C atom ratio was successfully synthesized.Monodispersed D‐PCOE microspheres were successfully fabricated.The quality of D‐PCOE microspheres is also investigated. [ABSTRACT FROM AUTHOR]

It is an undisputed fact that aging increases the risk of low-temperature cracking in asphalt pavement. Previous studies on aging have focused on oxidative aging, but few studies on thermoreversible aging have been reported. The existing literature has shown that thermoreversible aging has the same effect as oxidative aging on cracking of asphalt pavement in cold region, so it is obvious that the study of thermoreversible aging is of great practical significance to improve cracking of asphalt pavement. This paper introduces the current status of thermoreversible aging research from the concept, mechanisms, characterisation methods and effects, presents the problems of existing research and indicates the direction of further research, which is important for accurately characterising the mechanical properties of asphalt binders, controlling the waste addition ratio and improving the durability of asphalt pavement. [ABSTRACT FROM AUTHOR]

Objective To compare the surgical efficiency and postoperative evaluation indicators between active-fluidic pressure control phacoemulsification system and gravity-fluidics in dense nuclear cataract surgery. Methods A total of 60 patients (60 eyes) with age-related cataract admitted in the First Affiliated Hospital of Army Medical University from January 2020 to December 2020 were enrolled in this prospective study, and all of them were classified as NⅣ grade according to the Lens Opacities Classification System Ⅱ (LOCS Ⅱ). They were randomized into the active-fluidics group (n=30, phacoemulsification by active-fluidic pressure control system) or the gravity-fluidics group (n=30, phacoemulsification by gravity-fluidic system). Intraoperative parameters, such as cumulative dissipated energy (CDE), ultrasound total time (UTT), torsional amplitude (TA), torsion usage time (TUT), aspiration time (AT), and fluid used (FU) were recorded and compared between the 2 groups. Postoperative evaluation indicators, like central corneal thickness (CCT), central corneal edema and thickness (CCT) at 1 d after surgery were also collected and compared. Results There were no significant differences in preoperative best corrected distance visual acuity, CCT, and corneal endothelial cell count between the 2 groups. Intraoperatively, the active-fluidics group had significantly lower CDE, UTT, TUT, AT and FU than the gravity-fluidics group (P < 0.05), though TA did not differ. Moreover, the active-fluidics group also presented better UDVA (P=0.005), less increase of CCT (P=0.006), slighter central corneal edema (P < 0.001), and smaller proportion of patients with moderate to severe central corneal edema (P < 0.001) than the gravity-fluidics group in 1 d after surgery. Conclusion The active-fluidics configuration achieves a higher surgical efficiency than the traditional gravity-fluidics system in phacoemulsification of dense nuclear cataract, with slighter postoperative corneal edema, less change of CCT and faster recovery of UDVA.

Chromium is a common heavy metal element that is harmful to the ecosystem as well as human health, so sensitive detection of chromium ions in solution is important for life and health. In this paper, a series of Eu3+-doped KBi3F10 fluorescent powders were successfully synthesized by a one-step solvothermal method for the selective detection of Cr3+, CrO42− and Cr2O72− ions in an aqueous solution. When adjusting the pH value to 3 and adding PVP as an additive, the obtained KBi3F10:12%Eu3+ phosphor showed excellent red luminescence. Due to the competitive absorption and the inner filter effect of Cr3+, CrO42− and Cr2O72− ions, the red emission from Eu3+ ions produces fluorescence quenching, which can be used to detect them with good selectivity. And the detection limits are as low as 0.19 μM, 0.38 μM and 0.094 μM for Cr3+, CrO42− and Cr2O72− ions, respectively. Other metal ions and common anions showed little interference with chromium ion detection. The obtained fluorescent probe has good recyclability, accurate and reliable detection results, simple operation and low cost and is easy to promote, which make it an excellent three-in-one probe for chromium detection. [ABSTRACT FROM AUTHOR]

Yb3+/Er3+-doped Bi2(MoO4)3−z(WO4)z phosphors were synthesized via a hydrothermal method combined with subsequent calcination. Under the excitation of a light source of 980 nm, Bi2(MoO4)3:Yb3+/Er3+ phosphors exhibited strong upconversion green light and weak red light emissions. By doping WO42− in Bi2(MoO4)3:Yb3+/Er3+ phosphors, the upconversion luminescence intensity of the phosphors significantly enhanced, which is 42 times higher than that of the undoped WO42− phosphor. With an increase in WO42− doping content, the final color coordinates of Bi2(MoO4)3−z(WO4)z:Yb3+/Er3+ phosphors were (0.2352, 0.7274), which is closer to the standard green CIE coordinates. The maximum CP of WO42−-doped phosphors is as high as 116.68%, which is 74.44% higher than that of the undoped WO42− phosphor. Based on the thermally coupled energy levels (TCLs) of Er3+ (2H11/2/4S3/2 → 4I15/2) in Bi2(MoO4)2.7(WO4)0.3:14%Yb3+,3%Er3+ phosphor, the SR value reached a maximum of 0.0081 K−1 at 323 K and the SA value reached a maximum of 0.0099 K−1 at 398 K. The obtained Bi2(MoO4)3−z(WO4)z:Yb3+/Er3+ phosphors are suitable for upconversion luminescent materials for green displays and have potential advantages in optical temperature measurement. [ABSTRACT FROM AUTHOR]

ObjectiveTo compare the intraoperative efficacies of active-fluidic pressure control phacoemulsification system versus gravity-fluidics on intraoperative efficiency for primary angle-closure glaucoma with cataract, and investigate their effects on postoperative central corneal thickness(CCT), intraocular pressure(IOP), and count of corneal endothelial cells. MethodsA total of 24 patients(48 eyes) with primary angle-closure glaucoma and also accompanied with cataract undergoing surgical treatment in our ophthalmology department from June 2016 to December 2019 were prospectively recruited in this study. With the aid of Alcon Centurion Phacoemulsification Vision System, these patients underwent phacoemulsification with active-fluidics configuration in one eye(active group), and with gravity-fluidics configuration in another eye(gravity group). Their intraoperative parameters, such as cumulative dissipated energy(CDE), total ultrasound(US) time, torsion use time, torsion amplitude, aspiration time, and fluid use, were noted and compared between configurations. Endothelial cell loss, and CCT and IOP changes were evaluated at 1 d, 1 week, and 1 month postoperatively. ResultsThere were no significant differences in the baseline data between the 2 groups. The active group had significantly shorter total US time, torsion use time and aspiration time, and lower amount of fluid use than the gravity group(P