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151.
Zhenxing Ji Peihua Jiang Haiyang Yi Zhuang Zhuo Chunyuan Li Zhide Wu 《Entropy (Basel, Switzerland)》2022,24(6)
The issue of monitoring and early warning of rock instability has received increasing critical attention in the study of rock engineering. To investigate the damage evolution process of granite under triaxial compression tests, acoustic emission (AE) tests were performed simultaneously. This study firstly introduced two novel parameters, i.e., the coefficient of variation (CoV) of the information entropy and correlation dimension of the amplitude data from the AE tests, to identify the precursor of the failure of granite. Then the relationship between the changes in these parameters and the stress-time curve was compared and analyzed. The results of this study show that: (1) There is a strong correlation between the CoV of the information entropy and the failure process of granite. The granite failed when the CoV curve raised to a plateau, which could be used as an indicator of rock instability. (2) The fluctuation of the correlation dimension indicates the different stages during the loading process, i.e., the initial compaction stage, the linear elastic stage, the yield stage, and the failure stage. Each stage contains a descending and a rising process in the correlation dimension curve, and the exhibited starting point or the bottom point at the correlation dimension curve could be selected as the indicator point for the rock instability. (3) The combined analysis of the Information entropy and Correlation dimension can improve the accuracy of rock instability prediction. This study provides new insights into the prediction of rock instability, which has theoretical implications for the stability of subsurface engineering rock masses. 相似文献
152.
Although most list-ranking frameworks are based on multilayer perceptrons (MLP), they still face limitations within the method itself in the field of recommender systems in two respects: (1) MLP suffer from overfitting when dealing with sparse vectors. At the same time, the model itself tends to learn in-depth features of user–item interaction behavior but ignores some low-rank and shallow information present in the matrix. (2) Existing ranking methods cannot effectively deal with the problem of ranking between items with the same rating value and the problem of inconsistent independence in reality. We propose a list ranking framework based on linear and non-linear fusion for recommendation from implicit feedback, named RBLF. First, the model uses dense vectors to represent users and items through one-hot encoding and embedding. Second, to jointly learn shallow and deep user–item interaction, we use the interaction grabbing layer to capture the user–item interaction behavior through dense vectors of users and items. Finally, RBLF uses the Bayesian collaborative ranking to better fit the characteristics of implicit feedback. Eventually, the experiments show that the performance of RBLF obtains a significant improvement. 相似文献
153.
Jiajun Cao Yitao Wu Qi Li Weijie Zhu Zeju Wang Yang Liu Kecheng Jie Huangtianzhi Zhu Feihe Huang 《Chemical science》2022,13(25):7536
Pyrrolidine, an important feedstock in the chemical industry, is commonly produced via vapor-phase catalytic ammoniation of tetrahydrofuran (THF). Obtaining pyrrolidine with high purity and low energy cost has extremely high economic and environmental values. Here we offer a rapid and energy-saving method for adsorptive separation of pyrrolidine and THF by using nonporous adaptive crystals of per-ethyl pillar[6]arene (EtP6). EtP6 crystals show a superior preference towards pyrrolidine in 50 : 50 (v/v) pyrrolidine/THF mixture vapor, resulting in rapid separation. The purity of pyrrolidine reaches 95% in 15 min of separation, and after 2 h, the purity is found to be 99.9%. Single-crystal structures demonstrate that the selectivity is based on the stability difference of host–guest structures after uptake of THF or pyrrolidine and non-covalent interactions in the crystals. Besides, EtP6 crystals can be recycled efficiently after the separation process owing to reversible transformations between the guest-free and guest-loaded EtP6.Here we offer a rapid and energy-saving method for adsorptive separation of pyrrolidine and tetrahydrofuran by using nonporous adaptive crystals of per-ethyl pillar[6]arene.Pyrrolidine is an important feedstock in the chemical industry that has been widely used in the production of food, pesticides, daily chemicals, coatings, textiles, and other materials.1 Particularly, pyrrolidine is a raw material for organic synthesis of medicines such as buflomedil, pyrrocaine, and prolintane.2 Moreover, pyrrolidine is also used as a solvent in the semi-synthetic process of simvastatin, one of the best-selling cardiovascular drugs.3 In the chemical industry, there are many preparation methods for pyrrolidine. The most common way to obtain pyrrolidine is the gas-phase catalytic method using tetrahydrofuran (THF) and ammonia as raw materials;4 this is carried out at high temperature under catalysis by solid acids. However, separating pyrrolidine from the crude product is difficult because of similar molecular weights and structures between pyrrolidine (b.p. 360 K and saturated vapor pressure = 1.8 kPa at 298 K) and THF (b.p. 339 K and saturated vapor pressure = 19.3 kPa at 298 K), which result in complicated processes and large energy consumption.5 Therefore, it is worthwhile to find energy-efficient and simple methods to separate pyrrolidine from THF.Many techniques and materials, including porous zeolites, metal–organic frameworks (MOFs), and porous polymers, have facilitated energy-efficient separations of important petrochemicals and feedstocks, including THF and pyrrolidine.6,7 However, some drawbacks of these materials cannot be ignored.8 For example, the relatively low thermal and moisture stabilities of MOFs limit their practical applications. Therefore, the development of new materials with satisfactory chemical and thermal stabilities for pyrrolidine/THF separation is of high significance.In the past decade, pillararenes have been widely studied in supramolecular chemistry.9 Owing to their unique pillar structures and diverse host–guest recognitions, pillararenes have been used in the construction of numerous supramolecular systems.10 Recently, nonporous adaptive crystals (NACs) of macrocycles, which have shown extraordinary performance in adsorption and separation, have been developed by our group as a new type of adsorption and separation materials.11 Unlike MOFs, covalent-organic frameworks (COFs), and other materials with pre-existing pores, NACs do not have “pores“ in the guest-free form, whereas they adsorb guest vapors through cavities of macrocycles and spaces between macrocycles. NACs have been applied in separations of many significant chemicals such as alkane isomers, aromatics, and halohydrocarbon isomers.12 However, such materials have never been used to separate pyrrolidine and THF. Herein, we utilized pillararene crystals as a separation material and realized the selective separation of pyrrolidine from a mixture of pyrrolidine and THF. We found that nonporous crystals of per-ethyl pillar[6]arene (EtP6) exhibited a shape-sorting ability at the molecular level towards pyrrolidine with an excellent preference, while crystals of per-ethyl pillar[5]arene (EtP5) did not (Scheme 1). In-depth investigations revealed that the separation was driven by the host–guest complexation between pyrrolidine and EtP6, which resulted in the formation of a more stable structure upon adsorption of pyrrolidine vapor in the crystalline state. EtP6 crystals can also adsorb THF. However, when these two chemicals simultaneously exist as the vapor of a 50 : 50 (v/v) mixture, EtP6 prefers pyrrolidine as an adsorption target. Compared with previously reported NAC-based separation, this separation took place rapidly. 95% purity was achieved in 15 min, and the purity increased to 99.9% after 2 h of separation. Moreover, pyrrolidine was removed upon heating, along with the structural transformation of EtP6 back to its original state, endowing EtP6 with excellent recyclability.Open in a separate windowScheme 1Chemical structures and cartoon representations: (a) EtP5 and EtP6; (b) THF and pyrrolidine.EtP5 and EtP6 were prepared as previously described and then a pretreatment process was carried out to obtain guest-free EtP5 and EtP6 (Fig. S1–S4†).13 According to powder X-ray diffraction (PXRD) patterns, activated EtP5 and EtP6 (denoted as EtP5α and EtP6β, respectively) were crystalline, and the patterns matched previous reports (Fig. S5 and S6†).14 Studies from our group indicated that EtP5α and EtP6β crystals were nonporous, presumably due to their dense packing modes.We first investigated the adsorption capabilities of EtP5α and EtP6β towards pyrrolidine and THF vapors. Based on time-dependent solid–vapor adsorption procedures, both EtP5α and EtP6β showed good ability to adsorb pyrrolidine and THF vapors. As shown in Fig. 1a, the adsorption amount of THF in EtP5α was higher than that of pyrrolidine. It took 6 hours for EtP5α to reach saturation points for adsorption of both pyrrolidine and THF vapors. The final storage of THF in EtP5α was 2 : 1 (molar ratio to the host), whereas the storage of pyrrolidine was 1 : 1. It seemed that the THF vapor was favored to occupy EtP5α, which was ascribed to the relatively lower boiling point of THF. A similar phenomenon was found for EtP6β. Time-dependent solid–vapor adsorption experiments for pyrrolidine demonstrated that it took just 1 hour to reach the saturation point, while it took 4 hours for the THF vapor (Fig. 1b). The adsorption amount of THF vapor was twice that of pyrrolidine. 1H NMR spectra and thermogravimetric analyses (TGA) further confirmed the adsorption and storage of THF and pyrrolidine in both hosts (Fig. S7–S16†). Meanwhile, in the desorption process, adsorbed pyrrolidine and THF in EtP6β were easily released under reduced pressure and heating. Based on these data, it was clear that pyrrolidine could be adsorbed rapidly by both EtP5α and EtP6β in molar ratios = 1 : 1, while THF could be captured in a relatively slow process. Structural changes after adsorption of these two vapors were analyzed via PXRD experiments, in which varying degrees of changes before and after adsorption were observed, evidencing the appearance of new crystal structures (Fig. 1c and d). Nevertheless, only slight differences were observed in the PXRD patterns after the adsorption of THF or pyrrolidine, which might be ascribed to the structural similarity of the two molecules.Open in a separate windowFig. 1Time-dependent solid–vapor adsorption plots of (a) EtP5α and (b) EtP6β for single-component pyrrolidine and THF vapors. PXRD patterns of (c) EtP5α and (d) EtP6β: (I) original activated crystals; (II) after adsorption of THF vapor; (III) after adsorption of pyrrolidine vapor.To study the mechanism of adsorption, guest-loaded single crystals were obtained by slowly evaporating either THF or pyrrolidine solutions of pillararenes (Tables S2 and S3†). In the crystal structure of THF-loaded EtP5 (2THF@EtP5, Fig. 2a and S17†),11a two THF molecules are in the cavity of one EtP5 molecule driven by multiple C–H⋯O hydrogen bonds and C–H⋯π bonds. EtP5 assembles into honeycomb-like infinite edge-to-edge 1D channels. In the crystal structure of pyrrolidine-loaded EtP5 (pyrrolidine@EtP5, Fig. 2b and S19†), one pyrrolidine molecule, stabilized by C–H⋯π interactions and C–H⋯O hydrogen bonds between hydrogen atoms on pyrrolidine and oxygen atoms on EtP5, is found in the cavity of EtP5. It''s worth mentioning that a hydrogen atom which is linked with the N atom of pyrrolidine also forms a strong hydrogen bond with an oxygen atom on the ethoxy group of EtP5. EtP5 forms imperfect 1D channels because of partial distortion of orientation. The PXRD patterns simulated from these crystal structures matched well with the experimental results (Fig. S18 and S20†), which verified that the uptake of vapors transformed EtP5α into pyrrolidine-loaded EtP5.Open in a separate windowFig. 2Single crystal structures: (a) 2THF@EtP5; (b) pyrrolidine@EtP5.In the crystal structure of THF-loaded EtP6 (2THF@EtP6, Fig. 3a and S21†), one EtP6 molecule encapsulated two THF molecules in its cavity with C–H⋯O interactions, forming a 1 : 2 host–guest complex. Although 1D channels are observed, EtP6 adopts a slightly different conformation, caused by the presence of THF. Moreover, the PXRD pattern of EtP6β after adsorption of THF vapor matches well with that simulated from 2THF@EtP6, which is evidence for the structural transformation upon adsorption. In the crystal structure of pyrrolidine-loaded EtP6 (pyrrolidine@EtP6, Fig. 3b and S23†), a 1 : 1 host–guest complex with pyrrolidine is found. Driven by C–H⋯π interactions and C–H⋯O hydrogen bonds formed by hydrogen atoms on pyrrolidine and oxygen atoms on EtP6, one pyrrolidine molecule is in the cavity of EtP6 with the nitrogen atom inside the cavity. The window-to-window packing mode of hexagonal EtP6 molecules in pyrrolidine@EtP6 contributes to the formation of honeycomb-like infinite edge-to-edge 1D channels, favorable for guest adsorption. Likewise, the PXRD result of EtP6β after adsorption of pyrrolidine is in line with the simulated pattern of pyrrolidine@EtP6, indicating that EtP6β transformed into pyrrolidine@EtP6 in the presence of pyrrolidine (Fig. S22 and S24†).Open in a separate windowFig. 3Single crystal structures: (a) 2THF@EtP6; (b) pyrrolidine@EtP6.According to the adsorption ability and different crystal structures after adsorption of guest vapors, we wondered whether EtP5α or EtP6β could separate mixtures of THF and pyrrolidine. We first evaluated separation by EtP5α. GC analysis indicated that the adsorption ratios of THF and pyrrolidine were 65.7% and 34.3%, respectively, when EtP5α was exposed to 50 : 50 (v/v) pyrrolidine/THF mixture vapor (Fig. 4a and S25†). Such adsorption was also illustrated by 1H NMR (Fig. S26†). Although EtP5α showed a preference for THF, the selectivity is not satisfactory and cannot be applied to industrial separation. The less satisfactory selectivity may be ascribed to the similar crystal structures of EtP5 after adsorption of THF or pyrrolidine and insufficient strong stabilizing interactions. The PXRD pattern of EtP5α after adsorption of the 50 : 50 (v/v) pyrrolidine/THF mixture vapor exhibited minor differences compared with that simulated from either 2THF@EtP5 or pyrrolidine@EtP5, due to poor selectivity (Fig. 4b).Open in a separate windowFig. 4(a)Time-dependent solid–vapor adsorption plot for EtP5α in the presence of 50 : 50 (v/v) pyrrolidine/THF mixture vapor. (b) PXRD patterns of EtP5α: (I) original EtP5α; (II) after adsorption of THF vapor; (III) after adsorption of pyrrolidine vapor; (IV) after adsorption of pyrrolidine/THF mixture vapor; (V) simulated from the single crystal structure of pyrrolidine@EtP5α; (VI) simulated from the single crystal structure of 2THF@EtP5α. (c) Time-dependent solid–vapor adsorption plot for EtP6β in the presence of 50 : 50 (v/v) pyrrolidine/THF mixture vapor. (d) PXRD patterns of EtP6β: (I) original EtP6β; (II) after adsorption of THF vapor; (III) after adsorption of pyrrolidine vapor; (IV) after adsorption of pyrrolidine/THF mixture vapor; (V) simulated from the single crystal structure of pyrrolidine@EtP6β; (VI) simulated from the single crystal structure of 2THF@EtP6β.Nevertheless, selective separation of THF and pyrrolidine was achieved with EtP6β. As shown in Fig. 4c, time-dependent solid–vapor adsorption experiments for a 50 : 50 (v/v) pyrrolidine/THF mixture were conducted. Unlike the phenomenon in single-component adsorption experiments, uptake of pyrrolidine by EtP6β increased and reached the saturation point rapidly (less than 2 hours), while capture of THF was negligible. According to the NMR and GC results (Fig. S27 and S28†), the purity of pyrrolidine was determined to be 99.9% after 2 hours of adsorption, which indicates the remarkable selectivity of EtP6β for pyrrolidine. The PXRD pattern of EtP6β after adsorption of the mixture was consistent with that from single-component adsorption, indicating the structural transformation in the crystalline state upon selective capture of pyrrolidine from the mixture. Although THF and pyrrolidine have similar molecular structures, their non-covalent interactions with EtP6 are different. We assume that the hydrogen bond between N–H and the oxygen atom on EtP6 stabilizes pyrrolidine and leads to such selectivity. More importantly, compared with previous adsorption processes using NACs reported by our group, the selective separation of pyrrolidine was completed rapidly. According to the GC results, the purity of pyrrolidine reached around 95% in the initial 15 min, while it usually takes hours for selective separations of other substrates using NACs. Increasing the adsorption time to 2 h improves the purity to over 99%. The rapid separation of pyrrolidine with high purity using EtP6β shows great potential in industrial applications.Apart from selectivity, recyclability is also an important parameter for an adsorbent. Consequently, recycling experiments were carried out by heating pyrrolidine@EtP6 under vacuum at 100 °C to remove adsorbed pyrrolidine. According to TGA and PXRD analysis, the recycled EtP6 solid maintained crystallinity and structural integrity that were the same as those of activated EtP6 crystals (Fig. S29 and S30†). Besides, it is worth mentioning that the recycled EtP6 solids were still capable of separating mixtures of pyrrolidine and THF without loss of performance after being recycled five times (Fig. S31†).In conclusion, we explored the separation of pyrrolidine/THF mixtures using NACs of EtP5 and EtP6. Pyrrolidine was purified using EtP6 from a 50 : 50 (v/v) pyrrolidine/THF mixture with a purity of 99.9%, but EtP5 exhibited selectivity towards THF. Moreover, the separation of pyrrolidine by EtP6 was extremely fast so that over 95% purity was determined within 15 min of adsorption. The rapid separation is unique among NAC-based separations. Single-crystal structures revealed that the selectivity depended on the stability of the new structures after adsorption of the guests and the non-covalent interactions in the host–guest complexes. PXRD patterns indicated that the structures of the host crystals changed into the host–guest complexes after adsorption. Additionally, the NACs of EtP6 exhibited excellent recyclability over at least five runs; this endows EtP6 with great potential as an alternative adsorbent for rapid purification of pyrrolidine that can be applied in practical industry. The fast separation with such simple NACs in this work also reveals that minor structural differences can cause significant changes in properties, which should provide perspectives on designs of adsorbents or substrates with specifically tailored binding sites. 相似文献
154.
Sijia Wu Wenjuan Chen Sujuan Lu Hailing Zhang Lianghong Yin 《Molecules (Basel, Switzerland)》2022,27(15)
The shikimate pathway is a necessary pathway for the synthesis of aromatic compounds. The intermediate products of the shikimate pathway and its branching pathway have promising properties in many fields, especially in the pharmaceutical industry. Many important compounds, such as shikimic acid, quinic acid, chlorogenic acid, gallic acid, pyrogallol, catechol and so on, can be synthesized by the shikimate pathway. Among them, shikimic acid is the key raw material for the synthesis of GS4104 (Tamiflu®), an inhibitor of neuraminidase against avian influenza virus. Quininic acid is an important intermediate for synthesis of a variety of raw chemical materials and drugs. Gallic acid and catechol receive widespread attention as pharmaceutical intermediates. It is one of the hotspots to accumulate many kinds of target products by rationally modifying the shikimate pathway and its branches in recombinant strains by means of metabolic engineering. This review considers the effects of classical metabolic engineering methods, such as central carbon metabolism (CCM) pathway modification, key enzyme gene modification, blocking the downstream pathway on the shikimate pathway, as well as several expansion pathways and metabolic engineering strategies of the shikimate pathway, and expounds the synthetic biology in recent years in the application of the shikimate pathway and the future development direction. 相似文献
155.
The traditional method for the determination of protein in food needs the operations of digestion, distillation, absorption, and titration; therefore, it is complicated and time-consuming and requires professional personnel. Is there a more convenient and faster detection method that can directly determine the ammonium ions in protein digestion solution to obtain the protein content of food and avoid the distillation–absorption–titration process? The feasibility of water ammonium ion test kits for food protein rapid detection was discussed here. After digestion, the protein in food transforms into ammonium ions in the digestion solution. Because of the variety of food, there are many different inorganic ions left in the food digestion solution, and at the same time, digestion agents are added in the digestion process and become potential interference factors in ammonium determination. Therefore, the detection accuracy of ammonium test kits needs to be evaluated first, including their anti-interference ability. The standard curve of ammonium was established by the test kit. When the ammonium concentration was 0.00–2.50 mg/L, the absorbance at 620 nm was linearly related to the ammonium concentration, the determination coefficient R2 was 0.9995, and the detection limit of this method was 0.01 mg/L. The influences of temperature, pH value, and reaction time on the test kit method were discussed. The precision was 0.90–3.33%; the repeatability was 1.71–4.86%; and the recovery rate of tap water, river water, and sea water was controlled within 90–103%. The anti-interference ability of the evaluated test kit was better than that of the national standard detection method. The test kit, combined with sample pretreatment and protein conversion formula, was used to detect protein in different types of food (milk powder, rice flour, wheat flour, soy, banana, milk, fish food, chicken food, and dog food). The results showed that there were no significant differences (ρ > 0.05) between the national method and the test kit method. The ammonium ion test kit method shortened the determination time and had higher sensitivity, showing its potential for the rapid determination of food protein. 相似文献
156.
Kewang Luo Ning Li Wei Ye Hanchao Gao Xinle Luo Baohui Cheng 《Molecules (Basel, Switzerland)》2022,27(14)
Stimulator of interferon gene (STING), an intracellular receptor in the endoplasmic reticulum, could induce the production of cytokines such as type I interferon (IFN) by activating the cGAS-STING signal pathway. In recent years, activation of STING has shown great potential to enhance anti-tumor immunity and reshape the tumor microenvironment, which is expected to be used in tumor immunotherapy. A number of STING agonists have demonstrated promising biological activity and showed excellent synergistic anti-tumor effects in combination with other cancer therapies in preclinical studies and some clinical trials. The combination of STING agonists and ICI also showed a potent effect in improving anti-tumor immunity. In this review, we introduce the cGAS-STING signaling pathway and its effect in tumor immunity and discuss the recent strategies of activation of the STING signaling pathway and its research progress in tumor immunotherapy. 相似文献
157.
Bingxue Lv Jiahao Ren Yang Chen Siyu Guo Minqian Wu Lijun You 《Molecules (Basel, Switzerland)》2022,27(15)
In this study, a polysaccharide-based hydrogel microsphere (SFP/SA) was prepared using S. fusiforme polysaccharide (SFP) and sodium alginate (SA). Fourier transform infrared spectroscopy (FT-IR) demonstrated that SFP was effectively loaded onto the hydrogel microsphere. Texture profile analysis (TPA) and differential scanning calorimetry (DSC) showed that, with the increase of SFP concentration, the hardness of SFP/SA decreased, while the springiness and cohesiveness of SFP/SA increased, and the thermal stability of SFP/SA improved. The equilibrium adsorption capacity of SFP/SA increased from 8.20 mg/g (without SFP) to 67.95 mg/g (SFP accounted 80%) without swelling, and from 35.05 mg/g (without SFP) to 81.98 mg/g (SFP accounted 80%) after 24 h swelling. The adsorption of crystal violet (CV) dye by SFP/SA followed pseudo-first order and pseudo-second order kinetics (both with R2 > 0.99). The diffusion of intraparticle in CV dye was not the only influencing factor. Moreover, the adsorption of CV dye for SFP/SA (SFP accounted 60%) fit the Langmuir and Temkin isotherm models. SFP/SA exhibited good regenerative adsorption capacity. Its adsorption rate remained at > 97% at the 10th consecutive cycle while SFP accounted for 80%. The results showed that the addition of Sargassum fusiforme polysaccharide could increase the springiness, cohesiveness and thermal stability of the hydrogel microsphere, as well as improve the adsorption capacity of crystal violet dye. 相似文献
158.
Information-rich molecules provide opportunities for evolution. Genetically engineered materials are superior in that their properties are coded within genetic sequences and could be fine-tuned. In this review, we elaborate the concept of genetically engineered materials(GEMs) using examples ranging from engineered protein materials to engineered living materials. Proteinbased materials are the materials of choice by nature. Recent progress in protein engineering has led to opportunities to tune... 相似文献
159.
Tianyou Chen Wenyu Zhang Yuxin Liu Yuqiu Song Liyan Wu Cuihong Liu Tieliang Wang 《Molecules (Basel, Switzerland)》2022,27(14)
To explore the drying characteristics of soybean dregs and a nondestructive moisture content test method, in this study, soybean dregs were dried with hot air (80 °C), the moisture content was measured using the drying method, water status was analyzed using low-field nuclear magnetic resonance (LF-NMR) and the moisture content prediction models were built and validated. The results revealed that the moisture contents of the soybean dregs were 0.57 and 0.01 g/g(w.b.), respectively, after drying for 5 and 7 h. The effective moisture diffusivity increased with the decrease in moisture content; it ranged from 5.27 × 10−9 to 6.96 × 10−8 m2·s−1. Soybean dregs contained bound water (T21), immobilized water (T22) and free water (T23 and T23’). With the proceeding of drying, all of the relaxation peaks shifted left until a new peak (T23’) appeared; then, the structure of soybean dregs changed, and the relaxation peaks reformed, and the peak shifted left again. The peak area may predict the moisture content of soybean dregs, and the gray values of images predict the moisture contents mainly composed of free water or immobilized water. The results may provide a reference for drying of soybean dregs and a new moisture detection method. 相似文献
160.
Qi Nie Hao Jiang Si-Dong Zhong Qiang Wang Juan-Juan Wang Hao Wang Li-Hua Wu 《Entropy (Basel, Switzerland)》2022,24(7)
Community detection and structural hole spanner (the node bridging different communities) identification, revealing the mesoscopic and microscopic structural properties of complex networks, have drawn much attention in recent years. As the determinant of mesoscopic structure, communities and structural hole spanners discover the clustering and hierarchy of networks, which has a key impact on transmission phenomena such as epidemic transmission, information diffusion, etc. However, most existing studies address the two tasks independently, which ignores the structural correlation between mesoscale and microscale and suffers from high computational costs. In this article, we propose an algorithm for simultaneously detecting communities and structural hole spanners via hyperbolic embedding (SDHE). Specifically, we first embed networks into a hyperbolic plane, in which, the angular distribution of the nodes reveals community structures of the embedded network. Then, we analyze the critical gap to detect communities and the angular region where structural hole spanners may exist. Finally, we identify structural hole spanners via two-step connectivity. Experimental results on synthetic networks and real networks demonstrate the effectiveness of our proposed algorithm compared with several state-of-the-art methods. 相似文献