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Abstract Organic heterostructures (OHTs) with the desired geometry organization on micro/nanoscale have undergone rapid progress in nanoscience and nanotechnology. However, it is a significant challenge to elucidate the epitaxial-growth process for various OHTs composed of organic units with a lattice mismatching ratio of > 3%, which is unimaginable for inorganic heterostructures. Herein, we have demonstrated a vivid visualization of the morphology evolution of epitaxial-growth based on a doped interfacial-layer, which facilitates the comprehensive understanding of the hierarchical self-assembly of core-shell OHT with precise spatial configuration. Significantly, the barcoded OHT with periodic shells obviously illustrate the shell epitaxial-growth from tips to center parts along the seeded rods for forming the core-shell OHT. Furthermore, the diameter, length, and number of periodic shells were modulated by finely tuning the stoichiometric ratio, crystalline time, and temperature, respectively. This epitaxial-growth process could be generalized to organic systems with facile chemical/structural compatibility for forming the desired OHTs.

For studying the influence of different rolling processes on the microstructure morphology and internal stress of pipeline steel， the temperature field and stress field of steel plate under different processes were studied by rolling process experiment and thermal mechanical coupling numerical simulation. Subsequently， the microstructure morphology and internal stress of steel plate were tested and analyzed by metallographic microscope and XRD. The results of an actual measurement of the surface temperature of steel plate showed that the error between the simulated value and the measured value was small， and the temperature field calculated by numerical simulation was reasonable，which could be the basis for stress field analysis. After the steel plate was water-cooled for 20 s，the maximum and minimum temperature differences between the steel plate core and corner were 318 ℃and 211 ℃respectively. The maximum and minimum stress difference between the core and corner of the steel plate was 417 MPa and 260 MPa respectively. In addition， the obtained microstructure was composed of bainite，martensite and ferrite. It could be concluded from the results of experiments and numerical analysis that， it was reasonable to control the final rolling temperature at 800～900 ℃and the cooling rate at 20 ～25 ℃/s. Under these process parameters， the phase transformation nucleation rate of the steel plate was high， the internal stress difference was small， and a mixed microstructure comprising of martensite， bainite and ferrite was finally formed.

The problem of data incompleteness has become an intractable problem for network representation learning(NRL) methods,which makes existing NRL algorithms fail to achieve the expected results.Despite numerous efforts have done to solve the issue,most of previous methods mainly focused on the lack of label information,and rarely consider data imbalance phenomenon,especially the completely imbalance problem that a certain class labels are completely missing.Learning algorithms to solve such problems are still explored,for example,some neighborhood feature aggregation process prefers to focus on network structure information,while disregarding relationships between attribute features and semantic features,of which utilization may enhance representation results.To address the above problems,a semantic information enhanced network embedding with completely imbalanced labels(SECT)method that combines attribute features and structural features is proposed in this paper.Firstly,SECT introduces attention mechanism in the supervised learning for obtaining the semantic information vector on precondition of considering the relationship between the attribute space and the semantic space.Secondly,a variational autoencoder is applied to extract structural features under an unsupervised mode to enhance the robustness of the algorithm.Finally,both semantic and structural information are integrated in the embedded space.Compared with two state-of-the-art algorithms,the node classification results on public data sets Cora and Citeseer indicate the network vector obtained by SECT algorithm outperforms others and increases by 0.86%~1.97% under Mirco-F1.As well as the node visualization results exhibit that compared with other algorithms,the vector distances among different-class clusters obtained by SECT are larger,the clusters of same class are more compact,and the class boundaries are more obvious.All these experimental results demonstrate the effectiveness of SECT,which mainly benefited from a better fusion of semantic information in the low-dimensional embedding space,thus extremely improves the performance of node classification tasks under completely imbalanced labels.

Abstract Organic photothermal cocrystals, integrating the advantages of intrinsic organic cocrystals and the fascinating photothermal conversion ability, hold attracted considerable interest in both basic science and practical applications, involving photoacoustic imaging, seawater desalination, and photothermal therapy, and so on. However, these organic photothermal cocrystals currently suffer individual cases discovered step by step, as well as the deep and systemic investigation in the corresponding photothermal conversion mechanisms is rarely carried out, suggesting a huge challenge for their further developments. Therefore, it is urgently necessary to investigate and explore the rational design and synthesis of high‐performance organic photothermal cocrystals for future applications. This review first and systematically summarizes the organic photothermal cocrystal in terms of molecular classification, the photothermal conversion mechanism, and their corresponding applications. The timely interpretation of the cocrystal photothermal effect will provide broad prospects for the purposeful fabrication of excellent organic photothermal cocrystals toward great efficiency, low cost, and multifunctionality.

Gastrin releasing peptide receptor (GRPR) is overexpressed in various tumors, and these GRPR-positive tumors have successfully and widely been targeted with GRPR antagonists. To achieve a good therapeutic effectiveness and less radioactive dosage administration, high cellular internalization is required. The cellular internalization of agonists is better than that of antagonists, but the severe side effects of agonists restrict their applications. In this study, we hypothesized that introducing membrane penetrating oligo-phenylene-ethynylene (OPE) to GRPR antagonist RM26 could increase the cellular internalization of antagonists. Therefore, two multi-functional compounds NOTA-OPE-1-RM26 and NOTA-OPE-2-RM26 were synthesized and labelled with 177Lu with high efficiency. The 177Lu labelled compounds 177Lu-NOTA-OPEs-RM26 were stable in saline, dulbecco’s modified eagle medium (DMEM) and newborn bovine serum. The in vitro experimental results indicated that the introduction of OPE-1 slightly increased the cellular internalization of the radiolabelled compounds while OPE-2 significantly increased the cellular internalization. In addition, the introduction of OPEs did not change the specific binding ability of RM26. The investigations indicated that introducing the OPE to increase the internalization was feasible.

The large-scale synthesis of organic heterostructure nanowires is challenging. Here, the authors report the synthesis of organic triblock nanowires via a lattice mismatch-free strategy.

Abstract Polymer hole‐transport layers (HTLs) are critical components of inverted perovskite solar cells (IPVSCs). Triphenylamine derivatives PTAA (poly[bis(4‐phenyl)(2,4,6‐trimethylphenyl)amine]) and Poly‐TPD (poly[N,N′‐bis(4‐butylphenyl)‐N,N′‐bis(phenyl)benzidine]) have been widely adopted as hole‐transport materials due to their perovskite passivation effects and suitable energy levels. However, the passivation mechanism (i.e., the functional group responsible for perovskite passivation) of triphenylamine derivative polymers remains unclear, hindering the development and application of this polymer type. Here, we develop a novel Poly‐TPD derivative, S‐Poly‐TPD, by replacing the n‐butyl functional group of Poly‐TPD with an isobutyl group to explore the influence of alkyl groups on HTL performance and top‐deposited perovskite properties. Compared with Poly‐TPD, the increased CH3‐terminal unit density and the decreased spatial distance between the –CH–CH3 and –CH2–CH3 units and the benzene ring in S‐Poly‐TPD not only enhanced the hole‐transport ability but also improved the perovskite passivation effect, revealing for the first time the role of the alkyl groups in perovskite passivation. As a result, the S‐Poly‐TPD‐based IPVSCs demonstrated high power‐conversion efficiencies of 15.1% and 21.3% in wide‐bandgap [MAPbI2Br(SCN)0.12] and normal‐bandgap [(FAPbI3)0.92(MAPbBr3)0.08] devices, respectively.

Zinc–air batteries are recognized for their environmental friendliness and high energy density; however, the slow kinetics of the oxygen reduction reaction (ORR) at the air electrode hinder their commercial viability. The research focuses on synthesizing cubic hollow carbon structures derived from Metal–Organic Frameworks (MOFs), which enhance catalytic performance through improved conductivity and mass transfer. The resulting Fe/Fe3C/HCNB catalyst demonstrates a half-wave potential of 0.826 V for ORR and achieves a peak power density of 274 mW cm−2 in zinc–air batteries, surpassing commercial Pt/C catalysts. Electrochemical impedance spectroscopy reveals that the hollow structure enhances hydrophilicity and reduces solution resistance, facilitating greater active site engagement in electrochemical reactions. The study concludes that the unique structural features of Fe/Fe3C/HCNB significantly improve discharge performance and stability, positioning it as a promising alternative for zinc–air battery applications. [ABSTRACT FROM AUTHOR]

Organic near‐infrared (NIR) emissive materials integrating the intrinsic NIR light advantages and organic semiconductor characters have generated immense scientific interest in fundamental science and practical application, including optical communications, night vision, surveillance, and biomedical applications. Nevertheless, the intrinsic energy gap law engenders a huge challenge to simultaneously meet longer emission wavelength and higher luminescence efficiency for organic NIR emitters. Herein, it is suggested that the purposefully molecular design and crystal engineering for novel organic NIR materials are urgently studied and explored. Herein, recent advances in novel organic NIR materials, mainly focusing on the hybridized local and charge transfer (HLCT) compounds, thermally activated delayed fluorescence (TADF) emitters, CT cocrystals, neutral π‐radicals, and excited‐state intramolecular proton transfer (ESIPT)‐active materials, are summarized. It is hoped that this perspective can afford a new insight into the fine design and synthesis of the desired organic NIR emitters.

Rationally designing and precisely constructing the dimensions, configurations and compositions of organic micro- and nanomaterials are key issues in material chemistry, but remain challenging. Here, the authors realize the fine synthesis of organic superstructure microwires via a hierarchical epitaxial-growth approach.

BackgroundBirth weight is associated with cardiometabolic factors at birth. However, it is unclear when these associations occur in fetal life. We aimed to investigate the associations between fetal growth in different gestational periods and cord blood cardiometabolic factors.MethodsWe included 1,458 newborns from the Born in Guangzhou Cohort Study, China. Z-scores of fetal size parameters [weight, abdominal circumference (AC), and femur length (FL)] at 22 weeks and growth at 22–27, 28–36, and ≥37 weeks were calculated from multilevel linear spline models. Multiple linear regression was used to examine the associations between fetal growth variables and z-scores of cord blood cardiometabolic factors.ResultsFetal weight at each period was positively associated with insulin levels, with stronger association at 28–36 weeks (β, 0.31; 95% CI, 0.23 to 0.39) and ≥37 weeks (β, 0.15; 95% CI, 0.10 to 0.20) compared with earlier gestational periods. Fetal weight at 28–36 (β, −0.32; 95% CI, −0.39 to −0.24) and ≥37 weeks (β, −0.26; 95% CI, −0.31 to −0.21) was negatively associated with triglyceride levels, whereas weight at 28–36 weeks was positively associated with HDL levels (β, 0.12; 95% CI, 0.04 to 0.20). Similar results were observed for AC. Fetal FL at 22 and 22–27 weeks was associated with increased levels of insulin, glucose, and HDL.ConclusionsFetal growth at different gestational periods was associated with cardiometabolic factors at birth, suggesting that an interplay between fetal growth and cardiometabolic factors might exist early in pregnancy.

Traditional villages are the common historical and cultural heritage of all mankind. With the intensification of urbanization, the continuation of traditional villages and the inheritance of historical and cultural heritage are facing risks. The research on the driving factors affecting the spatial distribution characteristics, heterogeneity and human land interaction of traditional villages provides a new idea for the protection of traditional villages. This study takes 137 traditional villages in Puxian area, a typical cultural area in the southeast coast, as the research object, analyzes the spatial distribution pattern of traditional villages by using spatial analysis method, and selects 13 factors to analyze the main driving forces and interaction mechanisms through geographical detectors. The results show that: (1) Puxian traditional villages are clustered and distributed, and the distribution among counties is uneven, mainly in the state of "one cluster and many scattered points" with more coastal areas and less mountainous areas. (2) Puxian traditional villages are mainly affected by many factors such as nature, space, society and culture. They are more densely distributed in areas with rich cultural heritage, fertile land, flat terrain, suitable climate, close to water systems, developed transportation, backward economy and dense population. (3) Cultural factors are the primary factors affecting the spatial distribution of traditional villages, the order of driving factors' explanatory power is: intangible cultural heritage (0.5160) > protected cultural relic units (0.3591) > distance from railway (0.3255) > night light remote sensing (0.3179) > elevation (0.3012) > population density (0.2671) > slope (0.2032) > soil type (0.1804) > precipitation (0.1750) > temperature (0.1744) > land use (0.1492) > distance from river (0.0691)>distance from highway (0.0530). The interaction of intangible cultural heritage, protected cultural relic units and distance from the railway is the dominant factor for the spatial differentiation of traditional villages. Among them, the interaction of intangible cultural heritage∩distance from the railway is the strongest, and the q-value is 0.79, which proves that the interpretation ability of the two factor model is much higher than that of the single factor model. The results of this study reflect that traditional villages and nature, space, society and culture are interdependent, so the protection of traditional villages should be adapted to local conditions. [ABSTRACT FROM AUTHOR]

Organic heterostructures attract attention in material chemistry but the precise bottom-up synthesis is still challenging. Herein the authors present a hierarchical self-assembly approach to synthesize one-dimensional organic heterostructures by regulating the noncovalent interactions.