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Simple Summary: As a national second-class animal in China, it is urgent to protect the wild population resources of Sinocyclocheilus. In this study, we constructed the first full-length transcriptome of Sinocyclocheilus multipunctatus from the molecular perspective, analyzed and inferred its phylogenetic relationships, divergence time, and whole-genome duplication events, and screened 220 positive selection genes involved in gene control, signal transduction, immune response, and other processes from the A- and B-subgenome of S. multipunctatus. This will provide basic support for future evolutionary and genomic studies on the cave adaptation mechanism of this species. Sinocyclocheilus multipunctatus is a second-class nationally protected wild animal in China. As one of the cavefish, S. multipunctatus has strong adaptability to harsh subterranean environments. In this study, we used PacBio SMRT sequencing technology to generate a first representative full-length transcriptome for S. multipunctatus. Sequence clustering analysis obtained 232,126 full-length transcripts. Among all transcripts, 40,487 were annotated in public databases, while 70,300 microsatellites, 2384 transcription factors, and 16,321 long non-coding RNAs were identified. The phylogenetic tree showed that S. multipunctatus shows a closer relationship to Carassius auratus and Cyprinus carpio, phylogenetically diverging from the common ancestor ~14.74 million years ago (Mya). We also found that between 15.6 and 17.5 Mya, S. multipunctatus also experienced an additional whole-genome duplication (WGD) event, which may have promoted the species evolution of S. multipunctatus. Meanwhile, the overall rates of evolutionary of polyploid S. multipunctatus were significantly higher than those of the other cyprinids, and 220 positively selected genes (PSGs) were identified in two sub-genomes of S. multipunctatus. These PSGs are likely to fulfill critical roles in the process of adapting to diverse cave environments. This study has the potential to facilitate future investigations into the genomic characteristics of S. multipunctatus and provide valuable insights into revealing the evolutionary history of polyploid S. multipunctatus. [ABSTRACT FROM AUTHOR]

Background and Purpose. Motor dysfunction of the lower limb is a common sequela in stroke patients. The aim was to evaluate the efficacy of cathodal transcranial direct current stimulation (ctDCS) combined with conventional gait rehabilitation (CGR) to compare and clarify the clinical rehabilitation efficacy of ctDCS on motor dysfunction of the lower limbs after stroke to improve the walking ability of stroke patients. Methods. A pilot double-blind and randomized clinical trial. Ninety-one subjects with subacute stroke were treated with cathodal/sham stimulation tDCS based on CGR (physiotherapy 40 min/d and occupational therapy 20 min/d) once daily for 20 consecutive working days. Computer-based stratified randomization (1 : 1) was employed by considering age and sex, with concealed assignments in opaque envelopes to ensure no allocation errors after disclosure at the study's end. Patients were evaluated at T0 before treatment, T1 immediately after the posttreatment assessment, and T2 assessment one month after the end of the treatment. The primary outcome index was assessed: lower limb Fugl-Meyer motor score (FMA-LE); secondary endpoints were other gait assessment and relevant stroke scale assessment. Results. Patients in the trial group performed significantly better than the control group in all primary outcome indicators assessed posttreatment T1 and at follow-up T2: FMA-LE outcome indicators between the two groups in T1 (P = 0.032 ; effect size 1.00, 95% CI: 0.00 to 2.00) and FMA-LE outcome indicators between the two groups in T2 (P = 0.010 ; effect size 2.00, 95% CI: 1.00 to 3.00). Conclusion. In the current pilot study, ctDCS plus CGR was an effective treatment modality to improve lower limb motor function with subacute stroke. The effectiveness of cathodal tDCS in poststroke lower limb motor dysfunction is inconclusive. Therefore, a large randomized controlled trial is needed to verify its effectiveness. [ABSTRACT FROM AUTHOR]

In order to improve the coordination efficiency of vehicle routing problem, a multi-level stochastic demand in ventory routing problem was established in this paper, which minimizes the total cost of the system by determining the relation among inventory of distribution center, fleets, and customer needs. Solving the Lagrangian dual problem by the traditional subgradient Lagrangian relaxation algorithm may easily cause oscillation and then slow down the solving speed. To tackle the problem, an improved subgradient Lagrangian relaxation algorithm was proposed. Compared with the traditional subgradient algorithm , the proposed method is faster and improves the quality of the approximate solution. [ABSTRACT FROM AUTHOR]

Simple Summary: The damage by Hippotiscus dorsalis (Hemiptera: Pentatomidae) has resulted in the substantial mortality of moso bamboo in South China. In this study, we survey the damage of H. dorsalis from 2005 to 2013 in Huzhou, Zhejiang Province, and evaluate the current and future potential distribution in China. The results revealed (1) the April mean temperature and April maximum temperature were the main factors affecting the damage of H. dorsalis, and (2) the significant expansion of high suitable areas in Anhui and Jiangxi Provinces under future climate circumstances. Hippotiscus dorsalis is the main pest of Phyllostachys edulis in South China. The relationship between climate change and outbreak of H. dorsalis, and the current and future distribution of H. dorsalis are unknown. This study aimed to confirm the effect of climate on population density and the attacked bamboo rate of H. dorsalis, using field survey data from 2005 to 2013 in Huzhou, Zhejiang Province, and to reveal the potential distribution of H. dorsalis under current and future climate conditions using the MaxEnt model. The damage investigation and distribution forecast revealed the following: (1) The mean monthly temperature and maximum temperatures were main factors affecting the population density and the attacked bamboo rate in April in the Anji county of Zhejiang Province; they are all significantly and positively correlated. (2) High suitable area will significantly expand in Anhui and Jiangxi Provinces under the future climate circumstances, and the total suitable area will present a decrease because of the precipitation restriction. The significant expansion of high suitable area in the Anhui and Jiangxi Provinces under future climate circumstances means that the affected provinces will face even greater challenges. These findings provide a theoretical basis for the early forecasting and monitoring of pest outbreaks. [ABSTRACT FROM AUTHOR]

The goal of financial management is to manage the purchase and sale of assets, the rational financing of funds, the management of cash flow in operations, and finally, the reasonable distribution of company profits in a certain task situation, which is simply the management of the "three statements" of the enterprise. The core issue of the financial mechanism is how to choose a centralized or decentralized management model, which requires the company to consider the internal and external environment, and according to the development of the company, the quality of employees and business characteristics of various factors, in order to make the best choice of the company's financial management model. Therefore, in the context of the epidemic, this article conducts research related to the financial management of listed companies based on convolutional neural network models (radial basis neural network, generalized regression neural network, wavelet neural network, and fuzzy neural network). This article, firstly, discusses the basic theories of macro- and micro-financial management of enterprises and financial management of listed enterprises, secondly, examines the overall financial management model of listed enterprises in China through methods such as the convolutional neural network model research method introduced in this article, and then, after an overall examination and analysis of the financial management situation of X-listed enterprises, finds the macro- and micro-status quo of financial management of listed enterprises in China under the epidemic, and in the sub. On the basis of the status quo, suggestions are made to build a financial management model that combines centralization and decentralization and to build a group financial risk management system. [ABSTRACT FROM AUTHOR]

At present, most multi-objective optimization algorithms do not consider the interaction between decision variables, but just optimize all variables as a whole. With the increase of decision variables, the performance of multi-objective optimization algorithms will decrease sharply. Aiming at the a-bove problems, a multi-objective optimization algorithm without parameter grouping and with large-scale variables (MOEA/DWPG) is proposed. By combining collaborative optimization with the decomposi-tion-based multi-objective optimization algorithm (MOEA/D), this algorithm designs a grouping method without parameters to improve the grouping accuracy of interaction variables and to enhance the algorithm performance when it handles the multi-objective optimization problems with large-scale variables. Experimental results show that the proposed algorithm is significantly superior to MOEA/D and other advanced algorithms on the multi-objective problems with large-scale variables. [ABSTRACT FROM AUTHOR]

Abstract The electron transport characteristics in organic small-molecule semiconductors BmPyPB and TmPyPB doped and undoped by Lithium carbonate (Li 2 CO 3) have been investigated by admittance spectroscopy measurements. It is found that the electron mobilities of doped films greatly improved that of undoped films. The electron mobilities of Li 2 CO 3 -doped films reach the orders of 10−4∼10−3 cm2V−1s−1, which is one or two orders of magnitude higher than that of undoped films (∼10−5 cm2V−1s−1). The electron mobility variation with electric field in TmPyPB: Li 2 CO 3 is the same as that in BmPyPB: Li 2 CO 3. It can be seen that the electron mobilities slightly decrease as the electric field increases. The electron transport mechanisms in the doped and undoped films have been further studied through atomic force microscopy. The performances of electroluminescent devices with correlating electron transport layers has also been investigated. Graphical abstract Image 10511 Highlights • The electron transport characteristics in organic small-molecule semiconductors BmPyPB and TmPyPB doped and undoped by Li 2 CO 3 have been investigated by admittance spectroscopy measurements. The electron mobilities of Li 2 CO 3 -doped films reaches the orders of 10−4∼10−3 cm2V−1s−1, which is higher than that of undoped films (~10−5 cm2V−1s−1). • The electron mobility variation with electric field in TmPyPB: Li 2 CO 3 is the same as that in BmPyPB: Li 2 CO 3. • We investigated the surface morphologies of the films before and after doping by AFM. The RMS of the doped films of BmPyPB:Li 2 CO 3 and TmPyPB:Li 2 CO 3 is as low as 0.3026 nm and 0.3691 nm, respectively, which is much smaller and favorable for the electron transport. It indicates that they have high as well as similar electron mobilities. [ABSTRACT FROM AUTHOR]

Schizothorax lissolabiatus is an economically important cold-water fish species in southwestern China. Because of water pollution and habitat destruction, the number of wild populations has dramatically decreased. In this study, we used PacBio single-molecule real-time (SMRT) sequencing and Illumina sequencing to generate the first full-length transcriptome and transcriptome, respectively. A total of 19 310 polished consensus reads (PC) were obtained, with an average length of 1379 bp and an N50 length of 1485 bp. Meanwhile, 12 253 transcripts were successfully annotated as known homologous genes. The pathway annotation indicated that the enrichment and expression of most genes were mainly related to membrane, signal transduction and binding, and immune response. Furthermore, we identified 16 Toll-like receptors (TLRs) by mining the data from the transcripts. Phylogeny analysis showed that S. lissolabiatus TLR genes (slTLRs) supported the classification of TLRs into six families as in other vertebrates. Selection pressure analyses showed that 16 slTLRs revealed purification selection at the overall evolutionary selection. Further, positive selection signals were still detected in eight slTLRs , and most of the positive selection sites were located in the leucine-rich repeat region (LRR domain) associated with the recognition of pathogenic microorganisms, indicating that the function of these slTLR genes may be affected. Tissue specific expression analysis showed all slTLRs are present in kidney, spleen and liver but the relative expression varied among tissues. In conclusion, this study not only provided a valuable resource of transcripts for further research on S. lissolabiatus , but also contributed to improve the current understanding of the evolutionary history of immune-related genes and the TLR gene family in S. lissolabiatus. • We constructed the first full-length transcriptome and transcriptome of Schizothorax lissolabiatus. • 16 TLRs from S. lissolabiatus was obtained. • 8 slTLRs underwent positive selection and most positively selected sites were found in LRR domain. • Most of slTLRs tended to be highly expressed in kidney and spleen. [ABSTRACT FROM AUTHOR]

Abstract: In this study, methoxy poly(ethylene glycol)‐chitosan‐poly ( l‐lysine) (mPEG‐CS‐PLL) was synthesized and characterized by 1H NMR, X‐ray diffraction spectrometry (XRD), and differential scanning calorimeter (DSC). mPEG‐CS‐PLL nanoparticles were prepared by ionic cross‐linking with tripolyphosphate (TPP) under mild conditions and used as a carrier for protein. To demonstrate the feasibility of mPEG‐CS‐PLL as a protein carrier, bovine serum albumin (BSA) was used as a model protein and encapsulated in the mPEG‐CS‐PLL nanoparticles by electrostatic binding. The system showed very high encapsulation efficiency and loading capacity for BSA which was up to 78% and 42%, respectively. Dynamic light scattering (DLS), transmission electron microscopy (TEM), and zeta potential study were further used to measure the size, morphology, and Zeta potential of the nanoparticles. The results indicated that the nanoparticles were spherical with a homogeneous size below 300 nm, and the system was positively charged about +21.78 mV. Moreover, the protein cumulative release from the protein delivery system could reach to 82.5% after 54‐h incubation in PBS (pH 7.2) at 37°C. Cell viability tests against L929 cells showed that the cytotoxicity of mPEG‐CS‐PLL polymers was very low, which was favorable to practical applications. It can be suggested from the above results that the mPEG‐CS‐PLL can be used as a safe and effective carrier for protein delivery. [ABSTRACT FROM AUTHOR]

Conjugated polymers consist of extended π-conjugated systems, which are a new generation of heterogeneous photocatalysts. Herein, a series of two-dimensional fully conjugated microporous polymers (benzobisoxazole-linked porphyrin-based conjugated microporous polymers, BBO-Por-CMP and BBO-MPor-CMPs, M = Zn, Cu, Ni) were designed and synthesized by using porphyrins as building block and benzobisoxazoles as bridge linker for the first time. They have three highlighted advantages for photocatalytic application, namely robust, non-toxic, visible-light active, making them attractive photocatalyst candidates when integrating with their intrinsic features. BBO-Por-CMP and BBO-MPor-CMPs with fully π-conjugated and rigid microporous networks efficiently improve light-harvesting capability in the long-wavelength visible light region. The bridge linker benzobisoxazole efficiently prevents the aggregation of porphyrins, increases the exposure of the majority of the porphyrin units to oxygen, and enhances photocatalytic capability. As a result, oxidants-free BBO-Por-CMP and BBO-MPor-CMPs enable efficiently degradation of high concentrations (25 mg/L) and wide range of dyes (RB, MB, MO) in a short time. Therefore, BBO-Por-CMP and BBO-MPor-CMPs can be considered as promising photocatalysts for dealing with dyes sewage. [ABSTRACT FROM AUTHOR]

The large-strain mechanical behavior of PA66 was investigated using shear-compression specimens (SCS) with two opposite slots machined at different angles (15°, 30°, 45°, and 50°). Results show that strain rate and slot angle affect the equivalent stress in different levels. Slot angle sensitivity affects both flow stress and hardening characteristics, and strain rate influences elastic deformation. Increasing the strain rate gradually increases the equivalent stress. SCS with a slot angle of 30° exhibits the largest equivalent stress and the greatest effect of strain rate. The stress-strain curve differs between cylindrical specimens and SCS under quasi-static conditions. The yield stress obtained by the cylindrical specimens is higher than that of SCS. A constitutive model is modified based on the Drucker-Prager criterion to describe the effect of hydrostatic pressure and strain rate on the equivalent yield stress of polymer materials. The theoretical formula predictions are consistent with experimental results, thereby confirming the feasibility of this constitutive relationship. [ABSTRACT FROM AUTHOR]

Abstract: In order to investigate effect of Ce on electrochemical properties of the Ti1.4V0.6Ni quasicrystal, (Ti1.4V0.6Ni)99.4Ce0.6 alloy ribbon is prepared by arc melting and subsequent melt-spinning technique. The electrochemical properties of the Ti1.4V0.6Ni and (Ti1.4V0.6Ni)99.4Ce0.6 are studied as negative electrode for nickel–metal hydride batteries in aqueous KOH solution. The structures of the alloys were characterized by XRD and TEM. Phase structure investigations of the (Ti1.4V0.6Ni)99.4Ce0.6 show that alloy mainly consist of the icosahedral quasicrystal (I-phase) and face centered cubic (FCC) phase with Ti2Ni-type structure. The electrochemical measurements demonstrated that the negative electrode made by (Ti1.4V0.6Ni)99.4Ce0.6 alloy showed an improved electrochemical reversibility and a considerably higher charge–discharge capacity when compared to the Ce-free base alloy. Its maximum discharge capacity is about 300 mAh/g, which is higher than that of Ti1.4V0.6Ni, and remains 270 mAh/g after 30 cycles at a current density of 30 mA/g. The discharge process is also characterized by electrochemical impedance spectroscopy. [Copyright &y& Elsevier]

Abstract: A new 3D lanthanide metal–organic framework Eu(BPT)(DMF)(H2O)•(H2O)0.5] (1) has been synthesized by self-assembly of Eu(III) ions and ligand biphenyl-3, 4′, 5-tricarboxylate under solvothermal reaction conditions. X-ray crystallography reveals that 1 exhibits a (3, 6)-connected topology, with dinuclear europium clusters as 6-connected nodes and C2-symmetric ligands BPT as 3-connected nodes. In addition, the luminescence sensitization of 1 via excitation of the ligand is highly efficient. [Copyright &y& Elsevier]

The quantum adiabatic theorem is the basis of adiabatic quantum computation. However, the exact necessary and sufficient conditions for adiabatic evolution are still under debate. We discuss the adiabatic condition of a system undergoing a special evolution route, and obtain an explicit formula that is necessary and sufficient for the adiabatic evolution in this route. Based on this formula, we find that the traditional adiabatic condition is neither sufficient nor necessary. Finally, we show that no adiabatic process can occur even the evolution speed goes to 0 in some examples, which is surprising since the adiabatic theorem states that if the evolution of a system is slow enough, the adiabatic process could occur. [ABSTRACT FROM AUTHOR]

The digital transformation of manufacturing industry refers to the integration and application of the new generation of information technology in the field of manufacturing in the context of the current digital economy development. Architecture is the foundation of the real economy, which is closely related to digital chemistry and industrial digitalization. On the one hand, high-tech manufacturing of digital information products such as terminal equipment, smart equipment, electronic components, and integrated circuits is the material basis of digital chemical industry. It is a product of traditional manufacturing, blockchain, and artificial intelligence. On the other hand, digital technologies such as simulation technology are the core of the development of manufacturing, the key to achieving precise market positioning, expanding product functions, and improving product quality and added value. Digital technology is an intellectual industry. From the perspective of investment returns, the investment behavior of enterprises is manifested as effective investment and invalid investment. If the capital cost during the investment process is lower than the company's income, the company will not increase the investment amount for any reason, so it will not receive enough investment. Due to the low threshold of investment income, investment growth exceeding a certain threshold will actually reduce investment income and lead to excessive investment. In this context, this article studies the digital transformation of corporate enterprises based on algorithms: green innovation in investment efficiency organizations. This article deeply studies the status quo and the advantages of green innovation investment in digital technology and puts forward corresponding suggestions. [ABSTRACT FROM AUTHOR]

First-principles calculations based on density functional theory were used to investigate the electrochemical performance of monolayer γ-PC for Na- and K-ion batteries. Molecular dynamics simulations indicate that the monolayer γ-PC have the thermal and dynamic stability. A substantial charge transfer from the Na/K atoms to the γ-PC sheet enhances the electrical conductivity of γ-PC. The results show that the adsorption energies of Na and K are 1.53 eV and 2.04 eV, respectively, which are much higher than Na/K bulk cohesive energy and sufficiently ensure stability and safety. Additionally, the low diffusion barriers on γ-PC monolayer are 0.034 eV for Na and 0.027 eV for K, indicating excellent rate performance. The γ-PC sheet has a high theoretical capacity for both Na (519.9 mAh/g) and K (326.6 mAh/g) ion batteries, which can satisfy the requirement of energy storage devices to anode materials. Our results strongly suggest that 2D γ-PC monolayer is an exceedingly promising anode material for both NIBs and KIBs with high adsorption energies, high capacity, and low diffusion barriers. [ABSTRACT FROM AUTHOR]

A π-conjugated urea-bearing phenyleneethynylene polymer (Poly-2) was rationally designed by the Sonogashira coupling condensation reaction and had been demonstrated to have a unique fluorescent quenching effect for the optical detection of all determined anions, especially for CN−. The fluorescent emission of Poly-2 was significantly quenched upon adding CN−, together accompanied with a continuous red shift of the emission peak from 442 to 464 nm with the cyanide concentration increased from 0 to 1.0 mM. On the contrary, its precursor polymer, Poly-1, itself also displayed fluorescent responsibility with all selected anions but had no obvious selectivity and tendency. For instance, the addition of highly basic CN−, N3−, AcO−, or F− to Poly-1 solution in DMF/H2O (v/v = 1:1) led to the photoluminescence amplification, while the addition of weakly basic anions like Cl−, I−, and Br− showed a fluorescence quenching effect. Both polymers were in a seriously self-aggregated state in solution no matter in the absence or presence of an anion. Interestingly, it was found that Poly-2 exhibited an aggregation-induced emission behavior, while Poly-1 had an aggregation-caused quenching effect, based on the relationship between photoluminescence and polymer aggregation state. The structural characterizations were carried out by NMR spectroscopy and size exclusion chromatography measurements; the photoluminescence properties of Poly-1 and Poly-2 together with anion sensing properties were followed by fluorescence spectroscopy, and the relationship between photoluminescence and aggregation behavior of both polymers in solution was investigated by dynamic light scattering measurements. [ABSTRACT FROM AUTHOR]

Chiral recognition has significant research value for understanding the specific bio‐functions and capacity for exploiting the utility of each enantiomer. A homochiral membrane by incorporating metal‐organic frameworks nanofibers into the chitosan matrix (MOF@CS) is synthesized. MOF@CS displays highly sensitive and quantitative detection of D/L‐Tyr. [ABSTRACT FROM AUTHOR]

Alkali metal doping has been identified as a vital step in facilitating an increase in the first hyperpolarizability(β0). To further explore this concept, we utilized Calix (Zhang et al., 2018) [3]pyrrole (3), Calix (Ma et al., 2017) [4]pyrrole (4), and Calix (Aloraini et al., 2022) [5]pyrrole (5) as our three ligands in this study. The choice of these ligands was based on their ability to undergo alkali metal doping, which ultimately led to an enhancement in the first hyperpolarizability. By doping alkali metal lithium, three new compounds Li@3, Li@4 and Li@5 were theoretically designed. Then the alkaline earthide Mg was doped onto the Li@3, and a new alkaline earthide compound Li+(3)Mg− was designed. The geometric structure and nonlinear optical properties of the molecules were studied using the CAM-B3LYP functional. The results show that Li+(3)Mg− has a considerable first-order hyperpolarizability, β0 = 21401 au, The β0 value for the 3 system is merely 37 au, whereas for the Li@3 system, it reaches a high of 12257 au Li+(3)Mg− exhibits a β0 value that is over 500 times greater than that of 3. It is evident that the electronic structure and nonlinear optical properties are significantly affected by the presence of alkali metal and alkaline earthide atoms doped in 3. The excess electron derived from alkali metal atoms and alkaline earthide atoms are significant contributors to the sudden increase in the β 0 within Li+(3)Mg−. We sincerely hope that the development and production of materials with nonlinear optical properties in this study can provide new ideas and methods for the innovation of electride. • The influence of the number of pyrrole rings on the first hyperpolarizability is revealed by Li atom doping Calix[n]pyrrole(n = 3, 4 and 5). • The alkali metal compound Li+(calix [3]pyrrole)M−(M = Li, Na and K) is formed by alkali metal doping Li@calix [3]pyrrole with good nonlinear optical response. • Li+(calix [3]pyrrole)N−(N Be, Mg and Ca) is formed by alkaline earth metal doping Li@calix [3]pyrrole with good nonlinear optical response. • Density functional theory calculation reveals the superiority of alkaline earth metal Li+(calix [3]pyrrole)Mg− in nonlinear optical response. [ABSTRACT FROM AUTHOR]

The use of efficient photocatalysts to remove mixed pollutants from wastewater is of significance for environmental remediation. In this work, a novel conjugated microporous polymer (TAPP-PD-CMP) was synthesized and applied as a visible light driven photocatalyst to simultaneously remove a heavy metal ion and an organic pollutant. TAPP-PD-CMP possesses a large specific surface area (375 m2 g−1), narrow band gap (1.76 eV) and good chemical and thermal (∼450 °C) stabilities. More importantly, the energy band structure of TAPP-PD-CMP (ELUMO = 0.23 eV and EHOMO = 1.99 eV) enables adequate band edge potentials for photoreduction of a heavy metal ion (Cr(VI)) and photooxidation of an organic pollutant (RhB). Experimental results demonstrate that TAPP-PD-CMP has excellent adsorption-photocatalytic performance towards Cr(VI) (90%, 3 h) and RhB (94%, 3 h) from mixed contaminant wastewater at the same time. Additionally, TAPP-PD-CMP, as an environmentally-friendly photocatalyst, exhibits recyclability and sustainability. Radical trapping experiments reveal a synergistic photocatalytic mechanism, and the excellent photocatalytic activity is ascribed to continuous consumption of electrons and holes, reducing the recombination of photo-generated electron–holes. This work provides a promising CMP photocatalyst and an idea based on energy band engineering to design suitable photocatalysts for mixed pollutant treatment. [ABSTRACT FROM AUTHOR]

We present a cooling scheme with a tripod configuration atomic ensemble trapped in an optomechanical cavity. With the employment of two different quantum interference processes, our scheme illustrates that it is possible to cool a resonator to its ground state in the strong cavity–atom coupling regime. Moreover, with the assistance of one additional energy level, our scheme takes a larger cooling rate to realize the ground state cooling. In addition, this scheme is a feasible candidate for experimental applications. [ABSTRACT FROM AUTHOR]

Metal phthalocyanine-linked conjugated microporous polymers (MPc-CMPs) have huge potential applications in energy conversion and storage systems. However, the inherent low conductivity limits their practical application. Herein, the MPc-CMPs are hybridized with highly conductive carbon nanotubes (CNTs) via the easy vacuum filtration method. Interestingly, the composite (denoted as CoPc-CMP/CNTs) shows the flexible feature, which can be served as the flexible binder-free electrode for supercapacitors (SCs). As expected, the flexible CoPc-CMP/CNTs exhibits a high specific capacitance of 289.1 F g−1 at a current density of 1 A g−1 and good capacity retention of 82.4% over 1350 cycles at a high current density of 10 A g−1. Furthermore, First-principle calculations are used to elucidate the superiority of CoPc-CMP to other analogues. The good electrochemical performance could be attributed to the synergistic effect from the high pseudocapacitance and good conductivity of CoPc-CMP as well as the capacitive contribution and good conductivity of CNTs. Our strategy provides a new avenue to develop the high-performance SCs via rational integration of MPc-CMPs with highly conductive CNTs. Metal phthalocyanine-linked conjugated microporous polymers are hybridized with highly conductive carbon nanotubes via the easy vacuum filtration method. Interestingly, the composite shows the flexible feature, which can be served as the flexible binder-free electrode for supercapacitors. Image 1 • Metal phthalocyanine-linked conjugated microporous polymers are synthesized. • Polymers are hybridized with carbon nanotube to form a flexible electrode. • The flexible electrode shows good electrochemical performance for supercapacitors. • Density functional theory calculations reveal its metallic property and superiority. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) have obtained widespread attention because of the non-toxicity and low cost of element sodium. In this paper, we used first-principles methods to investigate the adsorption and diffusion of Na atom on the surface of Si3C. Calculation results show that the adsorption energy and the diffusion barrier for Na on Si3C are 2.33 and 0.26 eV, respectively, suggesting Si3C has good stability and fast charge/discharge capability as for anode in SIBs. More importantly, the Si3C can adsorb 32 Na atoms, which makes the storage capacity up to 1031 mAh/g. These advantages further suggest that Si3C monolayer could become one of the excellent candidates for anodes in SIBs. [ABSTRACT FROM AUTHOR]

A new species, Sinocyclocheilus xingyiensis, is described based on specimens collected from a karst cave in Guizhou Province, China. The authors used an integrated taxonomic approach, including morphological and molecular data, to identify the new species as a member of the Sinocyclocheilu angularis group, and it can be distinguished from all other members of this group by a combination of the following features: two pairs of long barbels and long pectoral fins, 42–46 lateral‐line scales, 7 (13–14) on outer (inner) side of the first gill arch and 35 (14–15 + 4 + 16 − 17) vertebrae. Phylogenetic analyses based on the cytochrome b (cyt b) gene fragment suggest that S. xingyiensis is a sister lineage to Sinocyclocheilus flexuosdorsalis. The genetic distance (Kimura 2‐parameter) between the S. xingyiensis and S. angularis groups of Sinocyclocheilus species based on cyt b gene fragment ranged from 1.2% to 15.4%. [ABSTRACT FROM AUTHOR]

A series of cobalt(II) complexes bearing N-aryl-phenanthrene-o-iminoquinones have been prepared and characterized. The catalyst system (Ar-PI)CoCl(μ-Cl) 2 ClCo(Ar-PI)/MAO shows good catalytic activity and cis ‐1,4 selectivity (up to 96.2%) for 1,3‐butadiene polymerization. Several chlorine-bridging dinuclear Co(II) complexes bearing the Schiff base ligands N-aryl-phenanthrene-o-iminoquinones (Ar-PICoCl 2) were synthesized and characterized by elemental analyses, infrared analyses and X-ray crystallography. The X-ray crystallography analysis of Co(II) complex 2 revealed that the geometry around the cobalt centers is twisted quadrilateral configuration. Upon activation with MAO, these complexes showed good activities (82.5–98.3%) for 1,3-butadiene polymerization affording predominantly cis -1,4 polybutadiene (up to 96.2%). GPC showed that the polybutadiene have relatively narrow PDI (Mw/Mn = 1.20–2.21). [ABSTRACT FROM AUTHOR]

Three aluminum alkyl complexes bearing porphyrin derivatives were synthesized by pyrrole derivatives and benzaldehyde derivatives. These complexes were characterized by NMR and elemental analysis. These complexes are used for racemic-lactide polymerization. In the ring-opening polymerization of racemic lactide, complex 3(2,3,7,8,12,13,17,18-octamethyl-5,10,15,20-tetraphenylporphyrin aluminum methyl, R1=H, R2=Me in Scheme 2) with isopropanol showed the highest stereoselectivity, and an isotactic polylactide with a Pm of 0.68 was obtained. The polymerization kinetics with complex 3 as catalyst was studied in detail. The kinetics of the polymerization data indicated that the rate of polymerization initiated by complex 3 had first-order dependency on monomer and catalyst. There is a linear relationship between lactide conversion and the number average molecular weight of PLA. [ABSTRACT FROM AUTHOR]

A series of aluminum complexes bearing [ONNO]-type ligands were prepared using m-xylylenediamine and modified salicylaldehyde. These complexes were characterized by NMR spectroscopy and elemental analysis. These complexes were employed in l-lactide and rac-lactide polymerization. Upon activation with isopropanol, complex 3 showed the highest activity (monomer conversion 97.4%) amid these aluminum complexes for the ring-opening polymerization of l-lactide and complex 2 showed the highest stereoselectivity for the ring-opening polymerization of rac-lactide providing isotactic polylactide (PLA) with a Pm of 0.70. The polymerization kinetics utilizing 2 as an initiator was researched in detail. The kinetics of the polymerization data revealed that the rate of polymerization was first-order with respect to the monomer and the initiator. There was a linear relationship between the l-lactide conversion and the number-average molecular weight of PLA. [ABSTRACT FROM AUTHOR]

Highlights • Highly oriented GONS/CNF films were successfully fabricated by LBL method. • The prepared films exhibit ultrahigh oxygen and water vapor barrier property. • The P O2 of CNF film decreased by about 4 × 104 times with only 3.66 vol% GONS. Abstract Graphene oxide nanosheet/cellulose nanofiber (GONS/CNF) nanocomposite films with ultra-low gas permeable property were fabricated through layer-by-layer coating and hot pressing method. XRD results showed that GONS was completely exfoliated and well dispersed in CNF matrix. The images of SEM and GI-WAXS manifested that the exfoliated GONS was highly oriented along the film direction under a strong external shear flow field. Such unique structure endows GONS/CNF nanocomposites with ultrahigh oxygen barrier property and good water vapor barrier performance. With only 3.66 vol% GONS, the oxygen permeability coefficient of CNF film decreased by about 4 × 104 times, from 5.5 × 10−13 to 1.4 × 10-17 cm3 cm·cm-2 s-1 Pa-1. Meanwhile, the tensile strength and Young's modulus of the CNF film were respectively enhanced by 2 and 57 times. Furthermore, the thermal stability of CNF film was also improved with the incorporation of GONS. [ABSTRACT FROM AUTHOR]

In this work, water dispersible crosslinked fluorescent poly(triphenylamine- co -benzothiadiazole)s (PTPABT) nanoparticles have been synthesized via Suzuki-type coupling (A 3 + B 2 ) in a toluene/water miniemulsion. Dialysis method was used to purify the PTPABT nanoparticles with a diameter range of 40–70 nm. The good dispersion property of the polymer in water could be attributed to the small sizes of the PTPABT nanoparticles. The obtained PTPABT nanoparticles possess microporous characteristic and display bright red emission in aqueous solution, which makes them possible to detect the nitro-aromatic explosive in aqueous media by monitoring the photoluminescence. The sensing property of the polymer nanoparticles towards 1,3,5-trinitrobenzene (TNB) in aqueous media has been researched, resulting a Stern-Volmer quenching constant K sv of 1.22 × 10 4  M −1 . The most attractive character of the conjugated polymer nanoparticles is the combination of both physical stability and solution-processability, thus making them good candidates for sensors and optoelectronic applications. [ABSTRACT FROM AUTHOR]

Context: The adsorptions of toxic gases SO2 and H2S on 2D α/β/γ-FeB6 monolayer were investigated using density functional theory calculations. To analyze the interaction between gas molecule H2S/SO2 and α/β/γ-FeB6 monolayer, we calculated adsorption energy, adsorption distance, Mullikan charge, charge density difference, band structure, the density of states, work function, and theoretical recovery time. The adsorption energies show that H2S/SO2 is chemisorbed on α/β-FeB6 while H2S/SO2 is physiosorbed on γ-FeB6 monolayer. As a result, γ-FeB6 has a short recovery time for H2S (5.71×10−8 s)/SO2 (1.94×10−5 s) due to modest adsorption. Therefore, γ-FeB6 may be a promising candidate for reusable H2S/SO2 sensors at room temperature. Although H2S is chemisorbed on α/β-FeB6, as the working temperature rises to 500 K, the recovery time of α/β-FeB6 for H2S can decrease to 1.13×10−1 s and 2.08×10−1 s, respectively, which are well within the detectable range. So, α/β-FeB6 monolayer also may be a good candidate for H2S gas sensor. Methods: Calculations were performed at GGA-PBE/DNP level using the Dmol3 module implemented in the Material Studio 2018 software package. [ABSTRACT FROM AUTHOR]

In order to obtain stable humidity sensitive polyelectrolyte, crosslinked polyelectrolyte with cage-shaped polyhedral oligomeric silsesquioxane (POSS) and hydrophilic tetraphenylphosphonium bromide (TPPBr) units has been synthesized via Friedel-Crafts alkylation. The obtained polyelectrolyte POSS-TPPBr owns both porous structure and hydrophilic property. The structure of POSS-TPPBr has been characterized with fourier transform infrared spectroscopy (FT-IR), nitrogen (N 2 ) isotherms and scanning electron microscopy (SEM). Humidity sensor based on POSS-TPPBr was prepared, which demonstrated a good response towards humidity, with impedance changing three orders of magnitude over the whole relative humidity (RH) range and little humidity hysteresis. Further, the composited film of POSS-TPPBr blended with polystyrene (PS) was developed to enhance the film-forming capability of the crosslinked polymer. As we expected, the humidity hysteresis and recovery speed of POSS-TPPBr/PS sensor have been improved compared with POSS-TPPBr sensor. [ABSTRACT FROM AUTHOR]

A simple diiron dithiolate [( μ -S 2 C 4 N 2 H 2 )Fe 2 (CO) 6 ] ( M2 ) as mimic of the active site of [FeFe] hydrogenase catalyzed the reduction of protons to dihydrogen (H 2 ). The strength of the acid played an important role in controlling the mechanism of electrocatalytic proton reduction. The catalysis of weak acid (acetic acid) occurred around −2 V vs. Fc/Fc + , at which M2 did not have a counterpart in the absence of acid. The catalyst was actually the reduced form of M2 and an (E)ECEC mechanism was proposed. With a moderately strong acid (trifluoroacetic acid), two significant catalyses operated. Reduction of the 2e – + 2H + intermediate ([ M2 IM−H 2 ]) catalyzed the proton reduction at ca. −1.4 V, whereas a competed catalysis at ca. −1.6 V dominated when the protonation of the reduced form of [ M2 IM−H 2 ] exceeded H 2 elimination at higher acid concentrations. Upon addition of a strong acid (triflic acid), one of the ring nitrogen atoms could be protonated. After two successive one-electron reductions, the formed species proceeded a catalytic cycle via a CECE process at a comparatively mild potential of −0.65 V vs. NHE. [ABSTRACT FROM AUTHOR]

Ba0.5Sr0.5FeO3−δ (BSF) nanofibers are prepared via electrospinning and sintering at a temperature of 800 °C for 2 h to produce a pure cubic perovskite phase, with the aim of finding a high-performance cathode material suitable for proton-conducting solid oxide fuel cells (PCFCs) operating at medium temperatures. The results of SEM analysis showed that the BSF nanofibers are alternately stacked, presenting fluffy and uniform high porosity, which is favorable to the cathode polarization reaction of PCFCs. To balance the excessive coefficient of thermal expansion of the BSF cathode, it is combined with a negative thermal expansion (NTE) material NdMnO3−δ (NM). At 700 °C, the peak power density (PPD) of the BSF–NM cathode cell is 1170 mW cm−2, and the open-circuit voltage (OCV) of the single cell is 1.04 V. The corresponding polarization impedance (Rp) of the BSF–NM is 0.037 Ω cm2. This result is significantly better than the previously reported powder cathode BSF, indicating that the performance of PCFC can be further optimized by transforming the BSF cathode into a nanofiber state and compounding it with the NTE material NM. [ABSTRACT FROM AUTHOR]

Abstract Ultrathin Copper (Cu) films are of great research interest to the transparent conductive anodes thanks to their properties of low-cost, low electrical resistivity, high transparency in the visible spectral range, and high work function. In this paper, ultrathin Cu films were thermally deposited on glass substrates as the anodes, which show low sheet resistance of and high transmittance peaking at red spectral range. Red organic light-emitting diodes (OLEDs) with 4-(dicyanomethylene)-2- tert -butyl-6(1,1,7,7- tetrame thyljulolidyl-9-enyl)-4H-pyran (DCJTB) as dopant were fabricated based on the Cu anodes. With the modification of MoO 3 and light enhancement of microcavity effect, the red OLED on Cu anode achieves a maximum current efficiency of 8.85 cd/A and a maximum power efficiency of 8.63 lm/W, which is superior to that on ITO glass. Moreover, oxygen-plasma treatment on the Cu anodes has been found to be able to further increase the transmittance to 75% at 624 nm, leading to high efficiency red OLEDs without MoO 3 modification. The results may pave the way towards a low-cost and tailored transparent anode for red OLEDs in practical applications such as signal lighting and therapy applications. Graphical abstract Image 1005 Highlights • The 11-nm Cu film shows a transmittance of 65% at 624 nm and a sheet resistance of 6.5Ω/□. • For the red OLEDs on Cu/MoO 3 , a CE max of 8.85 cd/A and PE max of 8.63 lm/W were achieved. • The surface of CuO x film is the smoothest among the three films. [ABSTRACT FROM AUTHOR]

Guizhou is an important ecological barrier in the upper reaches of the Yangtze River and the Pearl River basins with abundant fish species. However, fish from these regions are threatened by anthropogenic activities, including overfishing and habitat destruction. Here, we assessed the fish diversity including more than half of the species from the region using DNA barcoding (partial sequence of cytochrome c oxidase subunit I (COI) gene). We obtained 800 mitochondrial COI barcode sequences from 82 genera, 18 families and 8 orders of fishes. The average Kimura two-parameter (K2P) distances within species and genera were 0.35% and 5.44%, respectively. The average interspecific distance was 15.54 times higher than the mean intraspecific distance. Moreover, DNA barcodes revealed 175 operational taxonomic units (OTUs) based on consensus demarcation schemes. Barcoding gaps were detected in 94.81% of morphospecies. Three fish species (Schistura fasciolata, Vanmanenia pingchowensis, and Misgurnus dabryanus) have considerable intraspecific variability, and each was divided into multiple molecular operational taxonomic units (MOTUs) using molecular definition methods (Automatic Barcode Gap Discovery, Refined Single Linkage, General Mixed Yule Coalescent, and Poisson Tree Processes), possibly indicating the occurrence of cryptic species. Altogether, our study reveals the complex diversity of fish species in Guizhou Province, serving as a reference for the conservation and monitoring of fish species in this region. [ABSTRACT FROM AUTHOR]

Cellulose films have aroused widespread interest by virtue of its promising processing performance, biodegradability, and good final properties, but the insufficient waterproof property limits their application, especially in packaging field. Herein, hydrophobic modified graphene oxide nanosheets (GONS)/cellulose nanofiber (CNF) (H-mGONS/CNF) films with favourable water resistance was fabricated via successive casting technique and dip-coating process. Scanning electron microscope (SEM) manifested that highly oriented GONS/CNF nanocomposites were wrapped between the hydrophobic layers, forming a sandwich-like structure with a smooth surface and dense structure. This unique structure endows the H-mGONS/CNF composite films with excellent environmental characteristics, such as waterproofness, thermal stability, mechanical properties, self-cleaning and strong resistance to exfoliation. This work enables ecofriendly development of H-mGONS/CNF films with superior water repellency properties for many industrial applications including food packaging, biomedical products and protective coatings. [ABSTRACT FROM AUTHOR]

Achieving a desired whitening effect through short treatments without using peroxide and without compromising the integrity of tooth enamel remains a challenge in teeth whitening. Here, we developed a highly safe and efficient photodynamic therapy (PDT) strategy based on visible light-activated bismuth oxyiodide nanoparticles for nondestructive tooth whitening. The Bi 7 O 9 I 3 nanoparticles (NPs) exhibited efficient photocatalytic activity owing to their narrow band gap, effectively harnessing the broad spectrum of visible light to generate ample electrons and holes. Meanwhile, the presence of oxygen vacancies, low oxidation state Bi3+ and the high specific surface area endow Bi 7 O 9 I 3 NPs with effective electron-hole separation ability and potent redox potentials. Empowered by these characteristics, Bi 7 O 9 I 3 NPs effectively catalyzed O 2 into radicals (O 2 •-), facilitating the degradation of dental surface pigment molecules for tooth whitening. Concurrently, they eradicated oral bacteria and bacterial biofilms adhering to tooth surfaces, thereby having a positive effect on the effectiveness of tooth whitening. This PDT strategy with Bi 7 O 9 I 3 NPs shows broad application prospects in tooth whitening. • A nondestructive tooth whitening photodynamic therapy method. • Visible light-activated Bi 7 O 9 I 3 nanoparticles for tooth whitening by generating O 2 •-. • Simultaneous removal of biofilm enhances the effect of teeth whitening treatment. [ABSTRACT FROM AUTHOR]

Pure molybdenum (Mo) additively manufactured via laser powder bed fusion is challenging due to its high laser reflectivity and sensitivity to cracking. To achieve crack-free pure Mo alloy and enhance production efficiency, this study employs a high-power (350 W) printing process with a layer thickness of 30 μm, resulting in the successful fabrication of pure Mo with a relative density of 99.2%. X-ray diffraction (XRD) and electron backscatter diffraction (EBSD) revealed that the pure Mo specimens prepared by LPBF process exhibited different preferential grain orientations and lattice distortions in various building directions, with higher texture strength on the XOZ plane and greater lattice distortion on the XOY plane. The hardness of the pure Mo specimens reached 208 HV, with uniaxial compressive strength and elongation at 535 MPa and 20.9%, respectively, surpassing existing literature values by 37.2% and 8.0%. Furthermore, the dry friction behavior and mechanism of LPBF-manufactured pure molybdenum were investigated for the first time and compared to traditional powder metallurgy. Consequently, this research offers valuable insights for manufacturing crack-free LPBF pure molybdenum components with 30 μm layer thickness, boasting superior mechanical and wear resistance. • Pure Mo was successfully fabricated with a relative density of 99.2% and no cracks using a high-power LPBF printing process. • Compressive performance and wear resistance of LPBF pure Mo were studied for the first time. • The coefficient of friction for LPBF pure Mo is lower compared to PM pure Mo. [ABSTRACT FROM AUTHOR]

A series of singlet and triplet wheel-type clusters obtained through an electronic method, i.e., adding two and four electrons into X©BnHnm [(X, m) = (B, +1), (C, +2) for n = 5; (X, m) = (Be, 0), (B, +1) for n = 6], have been studied theoretically. With the increase of the number of electrons, the sizes of peripheral boron rings tend to decrease due to the increase of negative charges on the boron rings. The results of the kinetic stability and the electronic stability suggest that the triplet C©B5H5 and singlet Be©B6H6 are stable and may be detected experimentally. Nucleus-independent chemical shift and molecular orbital analysis reveal that some wheel-type clusters with the planar ring possess aromaticity properties that are attributed to the delocalized π electrons conforming to the Huckel rule, i.e. 4n + 2 for singlets or 4n for triplets. These findings from this work are significant for designing novel wheel-type clusters. [ABSTRACT FROM AUTHOR]

It is important for life safety and scientific research to design new sensing materials for detecting CO, CH4, and CO2 from the environment. We theoretically designed a new Cr-doped graphene-like hexagonal borophene (CrB6) as potential sensor material for these gases. Carrying out first-principle density-functional calculations, we calculated the adsorption energy, band structure, adsorption distance, charge transfer, charge density difference, density of states, and partial density of states of CO, CH4, and CO2 gas molecules absorbed on CrB6 monolayer. The calculated results show that the adsorption behavior of CO is different from those of CH4 and CO2. CO adsorbed on CrB6 monolayer prefers chemisorption with the adsorption energy of − 2.59 eV while CH4 and CO2 adsorbed on CrB6 monolayer prefer physisorption with the adsorption energy of − 0.72 and − 0.69 eV. As a result, the different adsorption behaviors have significant influence on the band structures and density of states of CrB6 monolayer. We hope that our results can help experimentalists synthesize better sensor materials based on hexagonal borophene. [ABSTRACT FROM AUTHOR]

Abstract: The first photocatalytic [FeFe]-hydrogenase ([FeFe]-H2ase) mimic 3 with noble-metal-free benzothiazole as donating photosensitizer had been successfully constructed via an easily accessible approach, and fully characterized by various spectroscopic and X-ray crystallographic techniques. Steady-state spectroscopy and electrochemistry revealed the evidences indicating that the photo-induced electron transfer occurred in 3. The reduced [FeIFe0] species was further confirmed by laser flash photolysis and considered to be responsible for the light-driven H2 evolution. As a result, the photocatalytic system consisting of the photocatalyst 3 and the sacrificial electron donor in the presence of proton source indeed produced H2 with a turnover number (TON) of 24.2 under light irradiation. The TON indicated a remarkably photocatalytic efficiency for an [FeFe]-H2ase mimic assembled by the covalent combination of a photosensitizer to the catalytic center. The results demonstrated the tremendous potential of present synthetic strategy for the construction of compact, inexpensive, easily accessible [FeFe]-H2ase model complexes as photocatalysts. [Copyright &y& Elsevier]

An ionic liquid-supportedsynthetic method for the constructionof glycopeptides in high yields is reported. This method avoids theuse of large excesses of reagents and chromatographic purificationand, therefore, represents a useful addition to existing approachesfor the ionic liquid-supported synthesis of oligosaccharides and peptides. [ABSTRACT FROM AUTHOR]

[Display omitted] • A day-night photocatalyst WO 3 -FePc with dual reaction centers was synthesized. • The catalyst has enhanced visible light response and effective charge separation. • The synergistic effect of dual reaction centers improves photocatalytic activity. • WO 3 -FePc can degrade pollutants under day-night cycle with recyclability. In this article, we presented a novel WO 3 -FePc day-night dual reaction centers photocatalyst covalently modified by iron-tetra (N -carbonylacrylic) aminephthalocyanine (FePc), in which WO 3 as an electron-storage reservoir and FePc as a photosensitizer and Fenton reaction center, which synergistically improve photocatalytic activity. The photocatalytic performance of WO 3 -FePc was evaluated using Rhodamine B (RhB) as a model pollutant, and it exhibited remarkable efficiency, with degradation of 93.0% RhB achieved under visible light irradiation for 60 min, and 40.4% RhB degraded in the dark, corresponding to approximately 12.4 times the performance of WO 3 and 7.8 times that of FePc. In addition, the removal rates of methylene blue (MB), tetracycline hydrochloride (TC•HCl) and K 2 Cr 2 O 7 (Cr (VI)) by WO 3 -FePc under visible light were 99.9%, 99.9% and 81.5% in 20 min, respectively. The rapid charge separation and the synergistic effect between the photocatalytic center and the Fenton center lead to excellent photocatalytic performance. This study prepared a highly efficient photocatalyst WO 3 -FePc that can act continuously during both day and night, and its distinctive day-night dual reaction center provides a new way to overcome the limitations of traditional photocatalytic technology. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS 2) is a nonlinear optical material with graphene-like structure. In order to further improve the nonlinear optical performance of MoS 2 and expand the application fields of MoS 2 , we report a simple in-situ self-growth method to functionalize MoS 2 nanosheets with metal-organic framework (MOF) for the first time to pursuit excellent reverse saturable absorption performance and optical limiting performance. Firstly, defective MoS 2 nanosheets was obtained by chemical etching with H 2 O 2 and cysteamine was inserted into the sulfur vacancies under ultrasound to obtain MoS 2 –NH 2. Then 5,10,15,20-Tetra (4-carbomethoxyphenyl) porphyrin (TCPP) as MOF active growth sites were grafted on MoS 2 –NH 2 by amido linkage to obtain MoS 2 -TCPP in mild conditions. Finally, flower-like porphyrin-based CuMOF was grown on MoS 2 -TCPP by solvothermal method to obtain MoS 2 -CuMOF with stable structure. The third order nonlinear optical performance of MoS 2 -CuMOF were studied by Z-scan technique. It was found that the third order nonlinear absorption coefficient of MoS 2 -CuMOF was significantly improved compared with MoS 2. Under the same energy of laser irradiation, the third order nonlinear absorption coefficient of MoS 2 -CuMOF nanocomposite in solution was 6 × 10−10 m/W about 2.3 times of the pristine MoS 2 (2.6 × 10−10 m/W). After blending the above materials with polymethyl methacrylate (PMMA) to prepare a solid device, the third order nonlinear absorption coefficient of MoS 2 -CuMOF/PMMA was 18 × 10−10 m/W about 3.6 times of the MoS 2 /PMMA (5 × 10−10 m/W). And MoS 2 -CuMOF/PMMA had better optical limiting ability than MoS 2 /PMMA. The significant improvement in the performance of the composites can be attributed to the energy transfer between MoS 2 and CuMOF, and porphyrin aggregation was inhibited by PMMA after the preparation of devices. Energy transfer can be proved by fluorescence spectroscopy. This work not only provided an example for the covalent functionalization of MoS 2 , but also offered a new method for designing materials with excellent nonlinear optical performance. [Display omitted] • MOF was grown on MoS 2 by a simple in-situ self-growth method to prepare MoS 2 -CuMOF. • MoS 2 -CuMOF had larger third-order nonlinear absorption coefficient. • MoS 2 -CuMOF had excellent properties through energy transfer between components. • MoS 2 -CuMOF can be prepared into PMMA-based optical limiter. [ABSTRACT FROM AUTHOR]

A novel thermo-responsive 2,9(10),16(17),23(24)-tetrakis[(3-carboxyacrylamide) phthalocyaninato] zinc (ZnPc)-g-TiO2-g-poly(N-isopropylacrylamide) (PNIPAM) photocatalyst modified with phthalocyanines was prepared. The photocatalyst exhibited thermo-responsive properties due to the introduction of PNIPAM, which performed recovery for reuse above the lower critical solution temperature (LCST, about 26 °C). ZnPc-g-TiO2-g-PNIPAM effectively expanded the light response range to the visible light region and inhibited the recombination of electron–hole pairs, which enhanced the performance of the photocatalyst. As expected, ZnPc-g-TiO2-g-PNIPAM (0.3 g/L) exhibited excellent photocatalytic performance for the removal of Rhodamine B (RhB, 1.0 × 10−5 mol/L) and methylene blue (MB, 1.0 × 10−5 mol/L) under visible light, which reached 97.2% and 88.6% at 20 °C within 40 min, respectively. Furthermore, the influence of temperature upon photocatalytic performance was also investigated. When the temperature increased from 20 °C to 45 °C, the removal of RhB decreased by approximately 53.8%. The stability of the photocatalyst demonstrated that the photocatalytic activity was still above 80% for the removal of RhB after 3 cycles. Above all, this work provided an intelligent thermally responsive photocatalyst based on phthalocyanine for water purification under visible light. [ABSTRACT FROM AUTHOR]

This contribution reports the syntheses, structural analyses and properties of europium (Eu3+)- and terbium (Tb3+)-based coordination complexes of poly(N-isopropyl,N-methylacrylamide-stat-N,N-dimethylacrylamide) (poly(iPMAm-stat-DMAm)) copolymer, named as poly-Eu(III) and poly-Tb(III), respectively. In greater detail, poly(iPMAm85-stat-DMAm15) is first prepared by random copolymerization of N-isopropyl,N-methylacrylamide (iPMAm) and N,N-dimethylacrylamide (DMAm) via group transfer polymerization (GTP). Next, poly(iPMAm85-stat-DMAm15) is used as the polymer matrix for chelating with Eu3+ and Tb3+ cations at its side amide groups, to produce poly-Eu(III) and poly-Tb(III). Their structural characterizations by FT-IR spectroscopy and XPS confirm the formation of polymeric complexes. The study on their fluorescence emission characteristics and luminescence lifetime demonstrates that Poly-Eu(III) shows four strong emission peaks at 578, 593, 622, and 651 nm, which are responsible for the electron transitions from the excited 5D0 state to the multiplet 7FJ (J = 0, 1, 2, 3) states, respectively, and poly-Tb(III) also displays four emission peaks at 489, 545, 588, and 654 nm, mainly due to the electron transitions of 5D4 → 7Fi (i = 6, 5, 4, 3). The luminescence lifetimes of poly-Eu(III) (τpoly-Eu(III)) and poly-Tb(III) (τpoly-Tb(III)) are determined to be 4.57 and 7.50 ms, respectively. In addition, in aqueous solutions, poly-Eu(III) and poly-Tb(III) are found to exhibit thermoresponsivity, with their cloud temperatures (Tcs) locating around 36.4 and 36.8 °C, respectively. Finally, the cytotoxicity study on the human colon carcinoma cells LoVo and DLD1 suggests that the luminescent Eu3+ and Tb3+ in the chelated state with poly(iPMAm-stat-DMAm) show much better biocompatibility and lower toxicity than their inorganic salts. [ABSTRACT FROM AUTHOR]

It is well known that a thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) becomes turbid above a cloud point (CP) temperature. In this study, the phase transition changes of PNIPAM end-functionalized with pyrenyl group (Py-PNIPAM) were investigated in dilute aqueous solutions. Two types of Py-PNIPAMs were prepared; one is an ester-linkage type (Py-OCO-PNIPAM), and the other an amide-linkage type (Py-NHCO-PNIPAM). From temperature dependence of fluorescence and fluorescence-excitation spectra for these polymer solutions, the micelle-like aggregates formation was found to be more favorable in Py-OCO-PNIPAM. To elucidate the cause of the difference, the partial dipole moments (PDM) of end-pyrenyl groups was obtained by molecular orbital calculations. The PDM value of the ester linkage type was smaller than that of the amide linkage type. The smaller value of PDM in the ester linkage type may explain the reason for the higher ability to form a micelle of Py-OCO-PNIPAM if the pyrenyl groups are assumed to be the core in the micelle. [ABSTRACT FROM AUTHOR]

Stimuli-responsive luminescent hybrid nanoparticles consisting of a magnetite Fe3O4 core and a hydrophilic outer shell were synthesized. The shell was a thermo-responsive Eu(III) complex shell, which was synthesized as follows: first, 3-Methacryloxypropyl-trimethoxysilane (MEMO)-co-poly(N-isopropylacrylamide) (NIPAM) (MEMO-co-PNIPAM) copolymer was prepared by free radical polymerization. Subsequently, the copolymer chelated with Europium(III) ions to form a luminescent polymeric layer. Finally, the polymeric shell was grafted onto the Fe3O4 nanoparticles surface through chemical action. The sizes of fabricated nanoparticles with core–shell structure were controlled at about 30-45 nm. The as-synthesized nanocomposite particles had excellent fluorescence performance and thermo-responsive behavior, which possessed high color purity and produced red-emission at 613 nm. The lower critical solution temperature (LCST) of thermo-sensitive magnetic nanoparticles was at around 37–38 °C. Cell viability assays suggested that these nanoparticles showed excellent biocompatibility and fluorescence-intensity in vitro. [ABSTRACT FROM AUTHOR]

In this work, a series of asymmetric and symmetric porphyrin derivatives (structure types: A4, A3B1, trans-A2B2, cis-A2B2, A1B3, and B4) have been synthesized via a one-pot method and characterized by TLC, HPLC, FT-IR, 1H-NMR and UV-Vis to identify their structures and properties. The porphyrin derivatives with trans-A2B2 and cis-A2B2 structures are visually distinguished via single-crystal X-ray diffraction; the crystal morphology of trans-A2B2 is a needle-like structure. All porphyrin derivatives (I–VI) have excellent nonlinear optical (NLO) and optical limiting (OL) properties, and are investigated using the standard Z-scan technique. Porphyrin derivative III exhibits the maximum nonlinear absorption, nonlinear refraction coefficients and optical limitation threshold, and the values are 3.7 × 10−9 m W−1, −17 × 10−17 m2 W−1 and 0.11 J cm−2, respectively. The results demonstrate that the introduction of different substituent numbers (mono-, di- and tri-, tetra-) and substituent sites (trans-A2B2 and cis-A2B2) in the porphyrins could influence the NLO and OL properties. Structure regulation of porphyrin can lead to the adjustment of NLO and OL properties, and affect its practical NLO application in the future. [ABSTRACT FROM AUTHOR]

We suggest the possibility to build graphene analogue with the planar hexacoordinate wheel-type Fe@B6H6 cluster as the building block through studying theoretically the geometry, stability, and electron structure of its dimer and trimer as well as the dimerization of the two trimers. Employing the dehydrogenation route to polymerization, we can obtain the hexagonal boron sheet that are partly and uniformly filled by Fe atoms in the center of the holes, achieving uniform chemical doping and a very large hexagonal-hole density. Thus, we may offer a novel cluster-assembled material for experimental chemists to construct graphene analogue. [ABSTRACT FROM AUTHOR]