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[Purpose/Significance] New quality productive forces is the latest pattern of productivity development under the background of data-driven intelligence. To explore the mechanism and practical way of bidirectional empowerment of knowledge service and new quality productive forces has important theoretical and practical significance for giving full play to the effectiveness of new quality of data elements, new power of digital intelligence technology and new application of intelligent service, so as to promote the cultivation of new quality productive forces and improve knowledge service. [Method/Process] Based on the summary of the development process of knowledge service and the new interpretation from the perspective of new quality productive forces, this study analyzes the internal relationship and external manifestations of the bidirectional empowerment of knowledge services and new quality productive forces, constructs the bidirectional empowerment mechanism of knowledge services and new quality productive forces, and proposes the bidirectional empowerment path. [Results/Conclusions] "Factor reorganization, scientific and technological innovation, and quality service" has become the internal relationship between knowledge service and new quality productive forces. Data factor as the core production factor, digital intelligence technology as the key production technology, and intelligence-driven new business forms and new models as the common carrier, which is an important basis for intelligent knowledge service and new quality productive forces bidirectional empowerment mechanism. Intelligent knowledge service cultivates the new quality productive forces through three important ways: accelerating scientific and technological innovation, opening up new ways and creating new business forms. New quality productive forces drives the development of intelligent knowledge service and improves the service by solving the resource dilemma, technology dilemma and talent dilemma, and creating new competitive advantages. This is an important manifestation of the bidirectional empowerment mechanism of new quality productive forces and intelligent knowledge service. After clarifying the empowerment basis and the performance of the bidirectional empowerment mechanism, this study proposes that the two kinds of empowerment should be realized from the following four aspects: a) Taking the market demand as the guide by mining new value and responding to new demand, and grasping the new quality growth engine; b) Taking data elements as the center, the compacting intelligent driving base is realized by building the data element empowerment system and improving the standardization of element utilization; c) Taking technological innovation as the key way by releasing the potential of key elements and creating fusion application scenarios to consolidate the foundation of fusion application; d) Starting from the application scenario as the starting point, the bidirectional empowerment mechanism is put into practice in various fields.

By using first-principles calculations and micromagnetic simulations, we investigate the electronic structure, magnetic properties, and skyrmions in two-dimensional Janus Cr 2 XYTe 6 (X,Y = Si, Ge, Sn, X ≠ Y) monolayers. Our findings reveal that the Cr 2 XYTe 6 monolayers are ferromagnetic semiconductors with a high Curie temperature (T c). The bandgap and T c can be further increased by applying tensile strain. In addition, there is a transition from the ferromagnetic to the antiferromagnetic state at a compressive strain. Both Cr 2 SiSnTe 6 and Cr 2 SiGeTe 6 exhibit a large magnetic anisotropy energy, which are mainly associated with the significant spin–orbit coupling of the nonmagnetic Te atoms rather than that of the magnetic Cr atoms. Interestingly, the Cr 2 SiSnTe 6 monolayer exhibits a significant Dzyaloshinskii–Moriya interaction of 1.12 meV, which facilitates the formation of chiral domain walls and skyrmions. Furthermore, under tensile strain, chiral DWs can be transformed into skyrmions if applying an external magnetic field. These findings suggest that Janus Cr 2 XYTe 6 monolayers hold promise for spintronic nanodevice applications. [ABSTRACT FROM AUTHOR]

Ultralong afterglow materials has special optical properties and a broad application prospect in the field of information encryption. A single afterglow color largely limits the application of afterglow materials in the direction of advanced encryption, and materials with dynamic afterglow are more popular. However, most of the dynamic afterglow materials are doped with multiple chromophores, and these materials with a single chromophore are rarely reported and have low lifetimes. Herein, a series of dynamic afterglow materials with time‐dependent phosphorescence is obtained by a simple one‐step strategy, and the longest lifetime reached 1.39 s, the maximum PLQY reached 85.9%, and the naked‐eye duration reached 20 s, which is the best level reported so far. The dynamic afterglow phenomenon is attributed to the multiple phosphorescence emission centers of the guest molecule with different decay rates, which results in a dynamic shift of the phosphorescence color. It is demonstrated through a series of characterizations that the covalent bonding interaction between the guest molecule and the host boric acid largely inhibits the nonradiative leaps of the guest molecule and provides it with a rigid matrix environment. Crucially, the dynamic afterglow material has been successfully applied in the field of displays and advanced information encryption. [ABSTRACT FROM AUTHOR]

Ultralong room‐temperature phosphorescent (URTP) materials have attracted wide attention in anti‐counterfeiting, optoelectronic display, and bio‐imaging due to their special optical properties. However, room‐temperature blue phosphorescent materials are very scarce during applications because of the need to simultaneously populate and stabilize high‐energy excited states. In this work, a stepwise stiffening chromophore strategy is proposed to suppress non‐radiative jump by continuously reducing the internal spin of the chromophore, and successfully developing a series of blue phosphorescent materials. Phosphorescence lifetimes of more than 3 s are achieved, with the longest lifetime reaching 5.44 s and lasting more than 70 s in the naked eye. As far as is know, this is the best result that has been reported. By adjusting the chromophore conjugation, multicolor phosphorescences from cyan to green have been realized. In addition, these chromophores exhibit the same excellent optical properties in urea and polyvinyl alcohmance (PVA). Finally, these materials are successfully applied to luminescent displays. [ABSTRACT FROM AUTHOR]

Tree detection and canopy area measurement are important and difficult tasks in forest inventory, which are important for understanding forest stand structure. This study utilized remotely piloted aircraft (RPA) aerial photography technology to collect remote sensing images of forests in Xiong County, China, creating a dataset comprising 1200 images of six tree species. Based on this dataset, the paper proposes an optimized model, Att-Mask R-CNN, for canopy detection and segmentation. Att-Mask R-CNN outperforms the original models (Mask R-CNN and MS R-CNN) by achieving 65.29% mean average precision for detection, 80.44% mean intersection over union for segmentation, and 90.67% overall recognition rate for the six tree species. In addition, a pixel statistics method based on segmentation masks is introduced for estimating the vertical projected area of individual tree crowns, and comparisons between the measured and predicted vertical projected area of the crowns of six tree species (100 trees of each class) show an overall goodness-of-fit R2 of 85% and a relative root-mean-square error rRMSE of 12.81%. By using remote sensing images from RPAs and optimizing existing deep learning models, the detection and segmentation of individual tree canopies can be achieved, resulting in a more accurate understanding of forest structure, which provides scientific support for forest management and resource monitoring. [ABSTRACT FROM AUTHOR]

Long‐life room temperature phosphorescent (RTP) materials hold significant potential in the fields of optoelectronic devices, information encryption, and bio‐imaging due to their excellent optical properties. However, achieving multi‐color tunable RTP materials has proven challenging. In this study, molecular engineering strategies are employed to select precursor molecules with varying degrees of conjugation such as phthalic anhydride (PA), naphtho[2,3‐c] furan‐1,3‐dione (23NA), and naphthalic anhydride (NA). By combining these guest molecules with a host boric acid matrix through a one‐step microwave method, carbon dots (CDs)composites (PA@BA, 23NA@BA and NA@BA) exhibiting excellent RTP properties are successfully prepared. As the degree of precursor conjugation increased gradually, the phosphorescence color modulation of the composites demonstrates satisfactory transitions from blue to yellow. Notably, CDs are derived in situ within the boric acid matrix while covalent and hydrogen bonds formed between CDs and borate matrix effectively suppress nonradiative leaps and facilitate composite RTP activation. Furthermore, the boric acid matrix acts as insulation against oxygen diffusion and prevents quenching of triplet excitons by external factors. The rationality behind phosphorescence emission mechanism and wavelength modulation is further conformed by density functional theory (DFT) calculations. Finally, CDs composites are successfully applied for advanced message encryption of text and images. [ABSTRACT FROM AUTHOR]

The sliding and manipulation of interlayer magnetism and magnetic topological textures in two-dimensional (2D) layered materials have recently received tremendous attention. In this work, using first-principles calculations, we report a structural phase transition induced by manipulating the interlayer distance using an in-plane biaxial strain in a 2H-VSe2 bilayer. This structural phase transition is accompanied by a semiconductor-to-metal transition, in-plane-to-out-of-plane magnetization switching, and a reversal in the chirality of the Dzyaloshinskii–Moriya interaction (DMI). The binding strength of the interlayer Se2–Se3 atoms and charge density difference can serve as indicators for this structural phase transition. Furthermore, the interlayer distance of Se2–Se3 atoms can be employed as a descriptor that perfectly characterizes the degree of symmetry breaking and the magnitude of the DMI resulting from the broken spatial symmetry due to sliding. In addition, using atomistic simulations, we identify magnetic topological textures such as interlayer antiferromagnetic (AFM) frustrated bimerons and interlayer AFM skyrmions with strain. These results are beneficial for understanding and manipulating the interlayer properties of 2D layered materials through in-plane biaxial strain. In addition, the interlayer AFM frustrated bimerons and skyrmions in bilayer VSe2, which can suppress the skyrmion Hall effect due to the canceled Magnus forces in the top and bottom layers, highlight the promising applications of VSe2 in next-generation information storage devices. [ABSTRACT FROM AUTHOR]

Organic room temperature phosphorescent (ORTP) materials have garnered significant interest in the fields of anti‐counterfeiting, optical display, and bio‐imaging owing to their distinctive optical properties. However, a major drawback of most existing ORTP materials is their short phosphorescence lifetime and low quantum yields (QYs), which greatly limit their applicability across multiple fields. In this paper, a covalently assisted host‐guest doping strategy that involves embedding three aminobenzoic acids with different carboxylate substitution positions into a cyanuric acid (CA) matrix through covalent bonding using microwave heating is proposed. All three prepared ORTP materials exhibit long phosphorescence lifetime exceeding 600 ms and high phosphorescence quantum yields (PhQYs) surpassing 20%. Among them, the composite of 2‐aminoterephthalic acid (2‐A) anuric acid stands out with its unique blue phosphorescence, boasting an exceptional absolute photoluminescence quantum yield (PLQY) of 98.95% and remarkable phosphorescence quantum yield (PhQY) of 76.42%, along with a long lifetime of 800 ms. Importantly, these high‐performance ORTP materials have been successfully utilized in anti‐counterfeiting and display applications. [ABSTRACT FROM AUTHOR]

Considering that the clay content in the western Liaoning region is high, the dominant fraction is <0.045 mm high ash in fine-grained low thermal coal and coal slurry. Self-developed CMC (Cone type Multi-stage Cyclone) multiple multistage small cone angle hydrocyclone groups are used for desliming flotation experiment research, product particle size analysis, hydrocyclone underflow product order evaluation tests and flotability evaluation. The results showed that 150 mm hydrocyclones with small cone angles are more suitable as the main desliming equipment before flotation than those with 75 mm and 50 mm hydrocyclones with small cone angles, but the bottom abortion rate is lower, and the phenomenon of "overflow running" is more serious. In the deslime-flotation process of the CMC multistage and small-cone angle hydrocyclone groups, the removal rate of fine particles with ash contents of 69.82% <0.045 mm in the original coal slime reaches 64.43%, basically solved the problem of "overflow and coarse running" of cyclones, and high ash fine clay minerals such as kaolin were enriched in the overflow. The group of three kinds of CMC hydrocyclone underflow products due to their different size widths shows that the flotability of the three underflows can be mixed into the float. Compared with raw coal direct flotation plants, the yield and combustible recovery rate can increase 2-3 times, and the floatability level is increased from extremely difficult to float to difficult to float, which can also be used for the underflow product floatability. The flotation process is different, strengthening the graded plant recycling process and providing a technological reference for better realization of narrow slime flotation. [ABSTRACT FROM AUTHOR]

Using first-principles calculations, we systematically investigate the electronic properties, chiral skyrmions and bimerons in two-dimensional (2D) Janus CrXY (X, Y = S, Se, Te, Cl, Br, I, and X ≠ Y) monolayers. We found that the categories of nonmagnetic atoms (X and Y in CrXY) determine whether CrXY is a ferromagnetic metal or a semiconductor. Unexpectedly, the CrBrS monolayer of these CrXY materials is a room temperature ferromagnetic semiconductor with a Curie temperature of 303 K, and it possesses an off-plane magnetic anisotropy energy of 0.06 meV. Besides, a strong Dzyaloshinskii–Moriya interaction (DMI) of 3.10 meV is found in CrTeI and is mainly induced by the strong spin–orbit coupling of the nonmagnetic atoms Te(I) rather than that of the magnetic Cr atoms. Furthermore, using micromagnetic simulations, skyrmions can be stabilized in CrSeBr without external magnetic fields. More importantly, the bimerons in CrSeCl with in-plane magnetic anisotropy can be transformed into skyrmions or a ferromagnetic state by controlling the direction of external magnetic fields. Our work investigates fourteen kinds of Janus monolayers, serving as guidelines for materials research on DMI, skyrmions and bimerons. [ABSTRACT FROM AUTHOR]

A new highly fluorescent hybrid material (CD@Eu‐MOF) is synthesized by encapsulating carbon dots (CD) prepared from citric acid and ethylenediamine on the basis of a metal‐organic framework (MOF) prepared from Eu3+ and 1,2,4‐benzenetricarboxylic acid. The prepared composite not only maintains the excellent fluorescence properties of CD and Eu3+, respectively, but also forms a dual‐emission fluorescence system, and the system has good stability in an aqueous solution. It is further used as a novel fluorescent probe for the detection of Fe3+, which can effectively exclude the interference of other metal ions from the detection, and the intensity ratio of IEu/ICD of CD@Eu‐MOF material has a good linear relationship with Fe3+ in the range of 1–200 µm. In this study, computer vision and backpropagation (BP) neural networks are used to train and fit the sample data, and it is verified that the actual fluorescence color of CD has a good linear relationship with Fe3+ concentration. In addition, the BP neural network also verifies that the fluorescence spectrum data of CD@Eu‐MOF also have a good linear relationship with Fe3+ concentration. This study provides a new method for the fabrication of ratio and colorimetric Fe3+ fluorescence sensors. [ABSTRACT FROM AUTHOR]

Ultralong room-temperature phosphorescent (URTP) materials have garnered significant attention in anti-counterfeiting, optoelectronic displays, and bio-imaging due to their unique optical properties. However, most URTP materials exhibit weak emission or are quenched in aqueous solutions. This study proposes a simple and effective strategy for preparing full-color aqueous URTP materials using a one-step microwave method. Guest molecules are embedded in a rigid cyanuric acid (CA) matrix formed from urea. By enhancing the conjugation of the guest molecules, a series of full-color URTP materials is successfully produced. These materials exhibit excellent phosphorescent properties, with a maximum phosphorescent lifetime of 7.96 s. Protected by the CA matrix, they retain phosphorescence even in aqueous environments, displaying an afterglow visible to the naked eye for over 30 s in water. Additionally, under low water content conditions, the materials exhibit exceptional water-enhanced properties, achieving a phosphorescence quantum yield (PhQY) of 40.4%. Importantly, these aqueous URTP materials can be prepared in just 5 min, showcasing great potential in information encryption and afterglow displays., (© 2024 Wiley‐VCH GmbH.)