Based on the principle of laser range measuring technology and precision angle division technology, a new measurement method of three-dimensional Laser Scanning for the volume of railway tank car and ...tank container is studied. The method mainly includes acquisition of point cloud data, processing the point cloud and volume calculation. In the processing point cloud, the T-Fo de-noising method is designed which is a new and efficient de-noising method. Three-dimensional laser scanning method, volumetric comparison method, the geometric method are compared, the results show that measurement by using three-dimensional laser scanning technology of the volume of railway tank car (container) is more accurate, safe, efficient, automatic. The expanded measurement uncertainty of three-dimensional laser scanning method is 3 × 10−3 (k = 2).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The past decade has witnessed tremendous research efforts devoted to two-dimensional (2D) materials and great progress made in both their fundamental studies and technique development. 2D ...light-emitting materials such as transition-metal dichalcogenides (TMDs) and phosphorene are receiving particular attention as a result of their intriguing electronic, optical and optoelectronic properties. The ability to tune their layer numbers, engineer their dielectric environment, form alloys, create van der Waals heterostructures,
etc.
provides further means to modulate their properties which have led to a number of interesting luminescence features and potential applications in lighting, imaging and sensing. As the map of 2D materials has expanded over the past few years, 2D organic and organic-inorganic hybrid materials, such as 2D polymers, metal-organic frameworks (MOFs), and organic-inorganic hybrid perovskites, have also emerged with merits of low cost, chemical versatility and solution processibility. Importantly, the wide tunability of their functional properties is enabled by the rational design and controlled modification of their compositions and structures at the molecular level. Herein, we present a critical review of 2D light-emitting materials by categorizing them into three main groups, namely 2D inorganic light-emitting materials, 2D organic light-emitting materials, and 2D organic-inorganic hybrid light-emitting materials. Within each group, we will describe their preparation methods and discuss their structural and chemical properties. Significant emphasis will be placed on strategies that can tune their luminescence properties, and their potential applications in various fields. Finally, we will summarize by stating the current challenges and future opportunities in the development of 2D light-emitting materials.
We review the recent development in two-dimensional (2D) light-emitting materials and describe their preparation methods, optical/optoelectronic properties and applications.
2D metal‐halide perovskites have attracted intense research interest due to superior long‐term stability under ambient environments. Compared to their 3D analog, the alternate arrangement of organic ...and inorganic layers leads to forming a multilayer quantum well (MQW), which endows 2D perovskites with anisotropic optoelectronic properties. In addition, the spacer layer functions as a hydrophobic barrier to effectively prevent 2D perovskite films from ion migration and moisture penetrating, thus realizing outstanding stability. Recently, 2D perovskites have been widely developed with abundant species. The stunning photovoltaic performance with the coexistence of long‐term stability and high‐power conversion efficiency (PCE) has been realized in 2D perovskite solar cells (PSCs), which paves an avenue for commercialization of PSCs. This review begins with an introduction of crystal structure and crystallization kinetics to illustrate the unique layer characters in 2D perovskites. Then, electron structure, excitons, dielectric confinement, and intrinsic stability properties are discussed in detail. Next, the photovoltaic performance based on recent Ruddlesden–Popper (RP), Dion–Jacobson (DJ), and alternating cations in the interlayer (ACI) phase 2D‐PSCs is comprehensively summarized. Finally, the confronting challenges and strategies toward structural design and optoelectronic studies of 2D perovskites are proposed to offer insight into the advanced underlying properties of this family of materials.
This review presents state‐of‐the‐art developments on 2D metal‐halide perovskite solar cells. The basic crystal structure, properties, and device photovoltaic performance on 2D perovskites are discussed in detail. Besides, the confronting challenges and corresponding strategies are proposed to offer insight into the underlying properties of this family of materials.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Tetracycline antibiotics (TCs) are one kind of broad spectrum bacteriostatic agents. However, excessive use of TCs will have a threat to the environment and human health. Therefore, it is necessary ...to develop a simple method for direct detection of TCs. Based on intrinsic peroxidase-like activity of gold nanoclusters (AuNCs), we used TC-specific aptamers (Apt) to improve the catalytic activity of AuNCs toward the peroxidase substrate 3,3′,5,5′-tetramethylbenzidine (TMB) oxidation by H2O2, and established a colorimetric sensing platform for TCs. The catalytic enhancement by Apt allows for sensitive colorimetric detection of TCs, and Apt as molecular recognition elements can specifically combine with TCs leading to high selectivity. This developed sensing platform can quantitatively detect TCs in the concentration range of 1–16 μM with a limit of detection (LOD) as low as 46 nM. Interestingly, the naked-eye detection capability of this method is estimated to be 0.5 μM. Finally, the detection of TCs in real samples like drugs and milk was validated.
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•A gold nanoclusters-based colorimetric aptasensor for tetracycline was presented.•Specificity and sensitivity of gold nanoclusters were greatly improved by aptamer.•The aptamer-enhanced peroxidase-like activity of gold nanoclusters was validated.•The sensor can accurately and reproducibly detect tetracycline in drugs and milk.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•A novel CaO2 bead was prepared to recover TSCFAs and P from iron-rich WAS.•Abundant acetate and Fe2+ in anaerobic supernatant were obtained after CaO2 beads treatment.•About 9% of P ...in sludge was recovered as Fe-P and Ca-P compounds on beads.•The decrease of Fe-phosphates and Fe-oxides in WAS were due to different mechanisms.•CaO2 beads effectively enriched DIRB and promoted iron-reduction related genes.
A novel composite CaO2 bead was prepared to improve total short-chain fatty acids (TSCFAs) production and phosphorus (P) recovery from iron-rich waste activated sludge (WAS) during ambient anaerobic fermentation. Results showed that CaO2 mass percentage of 5% and CaCl2:nylon66 = 1:1 (mass ratio) were the optimal prescription for the preparation of CaO2 beads with porous structure, loose morphology, and sustained-release of CaO2. The highest TSCFAs production (356 mg/g VSS) was observed and about 9% of P in sludge could be recovered on beads. The decrease of Fe-phosphate and Fe-oxides in the sludge were due to different mechanisms. Microbial community analyses showed that CaO2 beads effectively enriched dissimilatory iron-reducing bacteria (DIRB) and promoted iron-reduction related genes. After fermentation, the P-rich beads are easy to separate from sludge for further P recovery, and the supernatant carrying abundant acetate and Fe2+ can be returned to the wastewater treatment line to improve nutrient removal.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The current outbreak of coronavirus disease-2019 (COVID-19) poses unprecedented challenges to global health
. The new coronavirus responsible for this outbreak-severe acute respiratory syndrome ...coronavirus 2 (SARS-CoV-2)-shares high sequence identity to SARS-CoV and a bat coronavirus, RaTG13
. Although bats may be the reservoir host for a variety of coronaviruses
, it remains unknown whether SARS-CoV-2 has additional host species. Here we show that a coronavirus, which we name pangolin-CoV, isolated from a Malayan pangolin has 100%, 98.6%, 97.8% and 90.7% amino acid identity with SARS-CoV-2 in the E, M, N and S proteins, respectively. In particular, the receptor-binding domain of the S protein of pangolin-CoV is almost identical to that of SARS-CoV-2, with one difference in a noncritical amino acid. Our comparative genomic analysis suggests that SARS-CoV-2 may have originated in the recombination of a virus similar to pangolin-CoV with one similar to RaTG13. Pangolin-CoV was detected in 17 out of the 25 Malayan pangolins that we analysed. Infected pangolins showed clinical signs and histological changes, and circulating antibodies against pangolin-CoV reacted with the S protein of SARS-CoV-2. The isolation of a coronavirus from pangolins that is closely related to SARS-CoV-2 suggests that these animals have the potential to act as an intermediate host of SARS-CoV-2. This newly identified coronavirus from pangolins-the most-trafficked mammal in the illegal wildlife trade-could represent a future threat to public health if wildlife trade is not effectively controlled.
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FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The fast light-responsive dithienylethenes (DTEs) are one of the most attractive photochromic families because of their excellent thermal irreversibility and fatigue resistance. However, the ...all-visible-light-activated DTE system still remains challenging because most of them require the harmful high-energy ultraviolet light to trigger their photocyclization reaction. Here, we have for the first time borrowed a specific intramolecular proton transfer (IPT) process and rationally designed a series of all-visible-light-driven DTEs. Incorporating the IPT-functional group to DTE unit gives rise to an extra absorption band with a distinct red shift, which enables the photocyclization of DTEs under stimuli of visible light at 450 nm, as well as ensuring the desirable photoswitching efficiency. The isomerization from OH form to NH form induced by IPT can decrease the energy gap for excitation and photocyclization, thereby affording the all-visible-light-triggered photochromic performance, which can not only work well in a polar solvent system but also show its effectiveness in polymeric gel systems. In this regard, we can provide a general and reliable platform to construct all-visible-light-driven DTEs with excellent reversible photoswitching and broad applicability, especially with avoiding the use of harmful ultraviolet light to induce their photocyclization.
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IJS, KILJ, NUK, PNG, UL, UM
In this paper,we establish the existence of the global weak solutions for the nonhomogeneous incompressible magnetohydrodynamic equations with Navier boundary conditions for the velocity field and ...the magnetic field in a bounded domain Ω (∈) R3.Furthermore,we prove that as the viscosity and resistivity coefficients go to zero simultaneously,these weak solutions converge to the strong one of the ideal nonhomogeneous incompressible magnetohydrodynamic equations in energy space.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Freestanding MoS
2
nanosheets with different sizes were prepared through a simple exfoliated method by tuning the ultrasonic time in the organic solvent. Magnetic measurement results reveal the clear ...room-temperature ferromagnetism for all the MoS
2
nanosheets, in contrast to the pristine MoS
2
in its bulk form which shows diamagnetism only. Furthermore, results indicate that the saturation magnetizations of the nanosheets increase as the size decreases. Combining the X-ray photoelectron spectroscopy, transmission electron microscopy, and electron spin resonance results, it is suggested that the observed magnetization is related to the presence of edge spins on the edges of the nanosheets. These MoS
2
nanosheets may find applications in nanodevices and spintronics by controlling the edge structures.
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