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Tea (Camellia sinensis L.) is an important cash crop. In the context of climate change, analyzing the current distribution of tea trees and climate change environmental variables to predict the potential distribution area of tea trees in the future can help decision-makers make appropriate planting decisions and promote sustainable management. In this study, an optimized MaxEnt model was used to predict the limiting factors of tea tree growth and distribution under current and future climate change scenarios. The climate soil mixing model [area under the curve (AUC) = 0.934] performed excellently. The results showed that precipitation, temperature, slope, and soil factors all affected the distribution of suitable habitats for tea trees. Compared with the current distribution area of tea trees, under three shared socioeconomic pathways (SSP126, SSP245, and SSP585), the area of highly suitable habitats for tea trees will expand, especially in 2061–2080 and 2081–2100 years, and the suitable area will extend overall to the north of China, indicating that future climate change may create more new suitable habitats for tea production, especially in Shandong, Shaanxi, Guizhou, and Yunnan provinces. This study will provide important scientific insights for tea production decision-making, tea garden location selection, and future adaptation methods, and will help in the cultivation and transplantation of tea trees in the future.

To further advance the development for new-generations of high-performance, miniaturized and flexible electronic devices, it is particularly significant to research new-typed fluorescence-functionalized bi-aeolotropic conduction membrane. Herein, a unique topology optimization design philosophy is proposed, which highly integrates macroscopic with microscopic partitions to manufacture high-performance aeolotropic conduction membrane functionalized by fluorescence. Topologically devised Janus-like bi-layer membrane (JBM) with bi-aeolotropic conduction and red-green bicolor fluorescence is successfully assembled by using a bi-axis electro-spinning. [PANI/PMMA]//[Eu(TTA)3bipy/PMMA] Janus-structured micro-fiber and [PANI/PMMA]//[Tb(acac)3phen/PMMA] Janus-structured micro-fiber was respectively employed as microcosmic constructing unit to align directionally to build first layer (JBM-F) and second layer (JBM-S) of the JBM. Macroscopically, for the JBM, each layer has aeolotropic conduction, and furthermore, the conductive orientations of the two layers are vertical, and the insulated orientations are also vertical, leading in the bi-aeolotropic conduction of the JBM. The strongest conductive aeolotropism for each layer can reach 108 when the PANI/PMMA is 65%. The introduction of the Eu and Tb complexes into the Janus-structured micro-fiber gives the JBM excellent red-green bicolor fluorescence. The fluorescent traits can be employed to visualize the operational state of JBM. The high integration of Janus-structured micro-fiber possessing microcosmic partition with Janus-like bi-layer membrane possessing macrocosmic partition achieves the efficacious separation of electrical and fluorescent fillers to shun the deleterious interferences between two functions to obtain superior fluorescence and bi-aeolotropic conduction. Interestingly, the prepared flexible JBM can be applied as a reliable microcircuit interconnection, providing a basis for practical applications.

Outbreak updates are an integral part of crisis communication during epidemics. Regarding the COVID-19 crisis communication, localities in China present different strategies for managing outbreak updates, which largely determine the effect of crisis communication and the evolution of social psychology. Depending on the analysis of the update texts from 31 provincial (autonomous regions and municipalities directly under the central government) health committees in China, the study found the differences among the provincial outbreak updates and summarizes 12 innovative crisis communication ways. A coupling analysis was applied using the equilibrium-cognitive-psychosocial transition model to further expound on the psychological connotation and intervention potential of the crisis communication innovations. Coupling crisis communication with interventions has a positive effect on designing crisis communication strategies by taking into account psychological factors. It can help construct and optimize the public crisis communication systems and emphasize “care” in modernizing the emergency management capacity.

Multifunctional materials have more extensive applications than their counterpart single-functional materials due to their superior polyfunctions, among which fluorescent-conductive-magnetic (FCM) multifunctional materials have been extensively investigated for their unique performance and application value. However, the material properties may be degraded due to the adverse interactions among the fluorescent, conductive and magnetic materials with three different functions when they are directly blended. Hence, such adverse interactions brought by the direct contact of different functional materials should be avoided by designing and preparing unique structures. In this study, a one-dimensional (1D) tri-coaxial microbelt is innovatively designed, which can effectively separate and integrate different materials at the micro-level to obtain excellent macroscopic polyfunction. Generally, the preparation of tri-coaxial structure requires multistep procedures. To facilely construct the designed tri-coaxial microbelt, as a case study, a novel [CoFe2O4/polymethyl methacrylate (PMMA)]@[polyaniline (PANI)/PMMA]@[Tb(acac)3bpy/PMMA] (defined as [M@C@F]) tri-coaxial microbelts and arrays are synthesized through the one-pot direct electrospinning (ES) process. The tri-coaxial microbelts are assembled by the CoFe2O4/PMMA magnetic core layer, the PANI/PMMA conductive intermediate layer, and the Tb(acac)3bpy/PMMA insulated-fluorescent shell layer. It is the first time to integrate three different functions into the tri-coaxial microbelts and restrict three functions into three independent zones in the microbelt to shun adverse mutual interferences. The function of each layer can be regulated by adjusting the position and content of the three functional materials. Comparison with the control samples indicates that the property of the tri-coaxial microbelts array is directly impacted by structure and the arrangement modes of the building units. Hence, excellent macroscopic polyfunctions are obtained via designing and preparing microscopic partitioned building units and arranged modes. Array displays superior green fluorescence at 549 nm, tunable electrical conduction and magnetism. The new technique of one-pot direct construction of the tri-coaxial microbelts is significant and can be extended to for assemble other multifunctional materials. Moreover, the constructed [M@C@F] tri-coaxial microbelts and arrays have applications in various fields, such as micro-integrated circuits, microchips, and micro/nanodevices.

The increasing significance of theorem proving-based formalization in mathematics and computer science highlights the necessity for formalizing foundational mathematical theories. In this work, we employ the Coq interactive theorem prover to methodically formalize the language, semantics, and syntax of propositional logic, a fundamental aspect of mathematical reasoning and proof construction. We construct four Hilbert-style axiom systems and a natural deduction system for propositional logic, and establish their equivalences through meticulous proofs. Moreover, we provide formal proofs for essential meta-theorems in propositional logic, including the Deduction Theorem, Soundness Theorem, Completeness Theorem, and Compactness Theorem. Importantly, we present an exhaustive formal proof of the Completeness Theorem in this paper. To bolster the proof of the Completeness Theorem, we also formalize concepts related to mappings and countability, and deliver a formal proof of the Cantor–Bernstein–Schröder theorem. Additionally, we devise automated Coq tactics explicitly designed for the propositional logic inference system delineated in this study, enabling the automatic verification of all tautologies, all internal theorems, and the majority of syntactic and semantic inferences within the system. This research contributes a versatile and reusable Coq library for propositional logic, presenting a solid foundation for numerous applications in mathematics, such as the accurate expression and verification of properties in software programs and digital circuits. This work holds particular importance in the domains of mathematical formalization, verification of software and hardware security, and in enhancing comprehension of the principles of logical reasoning.

Geographic information systems have undergone rapid growth for decades. Topology has provided valuable modeling tools in the development of this field. Formal verification ofthe model of topological spatial relations can provide a reliable guarantee for the correctness of geographic information systems. We present a proof of the topological spatial relations model that has been formally verified in the Coq proof assistant. After an introduction to the formalization of the axiomatic set theory of Morse–Kelley, the formal description of the elementary concepts and properties of general topology is developed. The topological spatial relations between two sets are described by using the concept of the intersection value. Finally, we formally proved the topological spatial relations between two sets which are restricted to the regularly closed and the planar spatial regions. All the proof details are strictly completed in Coq, which shows that the correctness of the theoretical model for geographic information systems can be checked by a computer. This paper provides a novel method to verify the correctness of the topological spatial relations model. This work can also contribute to the creation and validation of various geological models and software.

In this study, a main marine engine with a rating power of 21,840 kW for a ship sailing in an actual voyage was obtained as the research object. The engine’s exhaust gas and jacket cooling water were adopted as the heat source of the organic Rankine cycle (ORC) system developed for the main marine engine. The engine can consume high-sulfur or low-sulfur fuel oil, respectively, according to the different emission control requirements. The impact of the use of high-sulfur or low-sulfur fuel oil, and variations in engine load, amount of recoverable waste heat, outboard seawater temperature, and the ship’s steam demand were comprehensively considered, and the validated ORC system model was used for the analysis of the system’s performance and the ship’s energy saving for the whole voyage. The results demonstrated that when the ship adopted high-sulfur or low-sulfur fuel oil, the maximum total net power output of the ORC system was 449.3 kW and 753.1 kW, respectively. During the whole voyage of 1610.7 nautical miles, when high-sulfur fuel oil was used, the ORC system reduced carbon emission by 40.3 tons and 33.8 tons, respectively, in summer and in winter, and the fuel saving rates were 2.53% and 2.12%; when low-sulfur fuel oil was used, the ship’s carbon emissions were reduced by 62.1 tons and 61.8 tons, respectively, in summer and in winter, and the fuel saving rates were 3.91% and 3.89%.

Formal verification technology has been widely applied in the fields of mathematics and computer science. The formalization of fundamental mathematical theories is particularly essential. Axiomatic set theory is a foundational system of mathematics and has important applications in computer science. Most of the basic concepts and theories in computer science are described and demonstrated in terms of set theory. In this paper, we present a formal system of axiomatic set theory based on the Coq proof assistant. The axiomatic system used in the formal system refers to Morse-Kelley set theory which is a relatively complete and concise axiomatic set theory. In this formal system, we complete the formalization of the basic definitions of sets, functions, ordinal numbers, and cardinal numbers and prove the most commonly used theorems in Coq. Moreover, the non-negative integers are defined, and Peano's postulates are proved as theorems. According to the axiom of choice, we also present formal proofs of the Hausdorff maximal principle and Schröeder-Bernstein theorem. The whole formalization of the system includes eight axioms, one axiom schema, 62 definitions, and 148 corollaries or theorems. The “axiomatic set theory” formal system is free from the more apparent paradoxes, and a complete axiomatic system is constructed through it. It is designed to give a foundation for mathematics quickly and naturally. On the basis of the system, we can prove many famous mathematical theorems and quickly formalize the theories of topology, modern algebra, data structure, database, artificial intelligence, and so on. It will become an essential theoretical basis for mathematics, computer science, philosophy, and other disciplines.

Unique-structured [NaYF4:Yb3+,Tm3+/polymethylmethacrylate (PMMA)]//[polyaniline (PANI)/PMMA]//[CoFe2O4/PMMA] fluorescent-conductive-magnetic tricolor flag-shaped nanobelt and array (marked as FCM-TNA) are innovatively designed and constructed by using tri-axial parallel electrospinning. Partition of three independent functional zones is microscopically realized in the tricolor flag-shaped nanobelt to avoid harmful mutual influences among three functions via confining luminescent, conductive and magnetic substances into their own domains, and thus achieving superior fluorescent-conductive-magnetic trifunction. Tricolor flag-shaped nanobelt used as building unit ensures excellent fluorescence, anisotropic conduction and magnetism of FCM-TNA. FCM-TNA emits blue fluorescence upon 980-nm laser excitation. Conductance ratio of conductive direction to insulating direction in FCM-TNA reaches 2.54 × 108 when the mass percentage of PANI to PMMA is settled at 70%, achieving high conductive anisotropy. By adjusting the contents of NaYF4:Yb3+,Tm3+ NPs, PANI and CoFe2O4 NPs, FCM-TNA exhibits tunable up-conversion fluorescence intensity, conductive anisotropy and magnetism. The formative mechanisms of tricolor flag-shaped nanobelt and FCM-TNA are advanced, and construction technologies are also established. Furthermore, neoteric 3D tubes and 3D + 2D complete banner-typed structures with similar multi-functionalities are derived from the FCM-TNA by using different construction strategies. The new design philosophy and technique can provide support for the design and construction of other new multifunctional anisotropic conductive materials in the future.

The first complete chloroplast genome of Morella cerifera was obtained by illumina platform sequencing technology in this study. The size of genome is 158,943 base pairs, consist of a pair of IRs 26,043 bp in length, the LSC region of 88,167 bp and SSC region of 18,690 bp. The genome has 112 unique genes, among which 79 protein-coding genes, 29 tRNAs, and 4 rRNAs. Phylogenetic analysis revealed that M. cerifera clustered with M. rubra within Myricaceae.

SnO2 nanofibers were fabricated by calcination of the electrospun PVP/SnCl4 composite nanofibers. For the first time, SnS nanofibers and SnSe nanofibers were successfully synthesized by double-crucible sulfurization and selenidation methods via inheriting the morphology of SnO2 nanofibers used as precursors, respectively. X-ray diffraction (XRD) analysis shows SnS nanofibers and SnSe nanofibers are respectively pure orthorhombic phase with space group of Pbnm and Cmcm. Scanning electron microscope (SEM) observation indicates that the diameters of SnS nanofibers and SnSe nanofibers are respectively 140.54±12.80 nm and 96.52±14.17 nm under the 95 % confidence level. The photocatalytic activities of samples were studied by using rhodamine B (Rh B) as degradation agent. When SnS or SnSe nanofibers are employed as the photocatalysts, the respective degradation rates of Rh B solution under the ultraviolet light irradiation after 200 min irradiation are 92.55 % and 92.86 %. The photocatalytic mechanism and formation process of SnS and SnSe nanofibers are also provided. More importantly, this preparation technique is of universal significance to prepare other metal chalcogenides nanofibers.

Formal verification of mathematical theory has received widespread concern and grown rapidly. The formalization of the fundamental theory will contribute to the development of large projects. In this paper, we present the formalization in Coq of calculus without limit theory. The theory aims to found a new form of calculus more easily but rigorously. This theory as an innovation differs from traditional calculus but is equivalent and more comprehensible. First, the definition of the difference-quotient control function is given intuitively from the physical facts. Further, conditions are added to it to get the derivative, and define the integral by the axiomatization. Then some important conclusions in calculus such as the Newton–Leibniz formula and the Taylor formula can be formally verified. This shows that this theory can be independent of limit theory, and any proof does not involve real number completeness. This work can help learners to study calculus and lay the foundation for many applications.

In order to achieve high-yielding rate of Janus microfibers in electrospun product, conjugate electrospinning is employed via optimization of electrospinning conditions. Further, Janus microfibers array affording dual-functional performance of magnetism and fluorescence is fabricated by above technique. The unique structure has the advantage of realizing complete separation of fluorescent materials from magnetic nanoparticles, which can ensure high fluorescent intensity without remarkably adverse effect of magnetic substance. The diameter of the fibers in the array is 11.72 ± 0.09 μm. The emission peaks of Tb3+ are found and assigned to the transitions of 5D4 → 7F6 (490 nm), 5D4 → 7F5 (545 nm), 5D4 → 7F4 (581 nm) and 5D4 → 7F3 (620 nm). Compared with the counterpart contrastive samples, Janus microfibers array present higher comprehensive performance owing to the exceptional structure and directionally ordered arrangement. Moreover, the saturation magnetization can be tailored from 3.6 emu·g−1 to 24.0 emu·g−1 via adding various amounts of Fe3O4 NPs. This work provides an effective method to fabricate other advanced multifunctional materials. Keywords: Janus microfibers array, Magnetism, Fluorescence, Conjugate electro-spinning, Multifunctional materials

The formalization of mathematics based on theorem prover becomes increasingly important in mathematics and computer science, and, particularly, formalizing fundamental mathematical theories becomes especially essential. In this paper, we describe the formalization in Coq of eight very representative completeness theorems of real numbers. These theorems include the Dedekind fundamental theorem, Supremum theorem, Monotone convergence theorem, Nested interval theorem, Finite cover theorem, Accumulation point theorem, Sequential compactness theorem, and Cauchy completeness theorem. We formalize the real number theory strictly following Landau’s Foundations of Analysis where the Dedekind fundamental theorem can be proved. We extend this system and complete the related notions and properties for finiteness and sequence. We prove these theorems in turn from Dedekind fundamental theorem, and finally prove the Dedekind fundamental theorem by the Cauchy completeness theorem. The full details of formal proof are checked by the proof assistant Coq, which embodies the characteristics of reliability and interactivity. This work can lay the foundation for many applications, especially in calculus and topology.

In order to develop new-typed multifunctional composite nanofibers, PANI/Fe3O4/PVP flexible bifunctional composite nanofibers with simultaneous electrical conduction and magnetism have been successfully fabricated via a facile electrospinning technology. Polyvinyl pyrrolidone (PVP) is used as a matrix to construct composite nanofibers containing different amounts of polyaniline (PANI) and Fe3O4 nanoparticles (NPs). The bifunctional composite nanofibers simultaneously possess excellent electrical conductivity and magnetic properties. The electrical conductivity reaches up to the order of 10-3 S · cm-1. The electrical conductivity and saturation magnetization of the composite nanofibers can be respectively tuned by adding various amounts of PANI and Fe3O4 NPs. The obtained electricity-magnetism bifunctional composite nanofibers are expected to possess many potential applications in areas such as electromagnetic interference shielding, special coating, microwave absorption, molecular electronics and future nanomechanics. More importantly, the design concept and construct technique are of universal significance to fabricate other bifunctional one-dimensional nanostructures.

Aerial work platform is a special vehicle for carrying personnel to the appointed site in the air for operations. Therefore, the work platform requires high stability. This article proposes a sliding mode controller based on neural network for tracking control of folding-boom aerial work platform. Since the chattering caused by sliding mode controller with high-speed switching control may lead to system performance degradation, continuous control obtained from neural network system replaces discontinuous switching control to eliminate chattering. Furthermore, the whole system is proved to be stable by Lyapunov stability theorem. Finally, numerical results show that the designed controller can eliminate the chattering resulting from switching control in sliding mode controller and inhibit the vibration of work platform when there exists system uncertainty. Moreover, the controller is effective for the reduction of tracking error.

Polymer/ceramic composite solid electrolyte is an effective solution for the development of flexible solid-state lithium metal batteries. In this paper, a solid-state lithium-ion electrolyte composed of ceramic powder Li7La2.5Ce0.5Zr1.625Bi0.3O12 (LLCZBO) and lithium salt LiTFSI is added to PVDF-PEO. With the addition of 20 wt% LLCZBO, the electrolyte has a high ionic conductivity of 3.67 × 10−4 S·cm−1 at room temperature. The lithium symmetric battery can be cycled for a long time at a current density of 0.1 mA·cm−2. The battery with LiNi0.6Co0.2Mn0.2O2 (NCM) as the cathode can be cycled at room temperature at 0.1 C and obtain high coulombic efficiency. The excellent cycle performance and rate capability can be attributed to the high ionic conductivity of LLCZBO. These advantages indicate that the composite solid electrolyte (CSE) membranes is expected to be a perfect electrolyte for the next generation of solid-state lithium batteries.