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Cross-modal hashing encodes heterogeneous multimedia data into compact binary code to achieve fast and flexible retrieval across different modalities. Due to its low storage cost and high retrieval efficiency, it has received widespread attention. Supervised deep hashing significantly improves search performance and usually yields more accurate results, but requires a lot of manual annotation of the data. In contrast, unsupervised deep hashing is difficult to achieve satisfactory performance due to the lack of reliable supervisory information. To solve this problem, inspired by knowledge distillation, we propose a novel unsupervised knowledge distillation cross-modal hashing method based on semantic alignment (SAKDH), which can reconstruct the similarity matrix using the hidden correlation information of the pretrained unsupervised teacher model, and the reconstructed similarity matrix can be used to guide the supervised student model. Specifically, firstly, the teacher model adopted an unsupervised semantic alignment hashing method, which can construct a modal fusion similarity matrix. Secondly, under the supervision of teacher model distillation information, the student model can generate more discriminative hash codes. Experimental results on two extensive benchmark datasets (MIRFLICKR-25K and NUS-WIDE) show that compared to several representative unsupervised cross-modal hashing methods, the mean average precision (MAP) of our proposed method has achieved a significant improvement. It fully reflects its effectiveness in large-scale cross-modal data retrieval.

(E)-2-(2-(2,3-dibromo-4,5-dimethoxybenzylidene)hydrazinyl)-4-(3,4-difluorophenyl) thiazole (DDH-1) is novel small molecule compound synthesized in our previous work. This study found that DDH-1 could inhibit the proliferation of various human lung cancer cells. Particularly, the IC50 for A549 cells was 8.59 μM. Interestingly, we found that DDH-1 inhibits eIF4E/eIF4G interaction. The flow cytometry (FACS) results have indicated that DDH-1 may induce G0/G1 cycle arrest by inhibiting the expression of Cyclin D1 and CDK4. DDH-1 may also cause apoptosis through the caspase-dependent pathway. Study of these mechanisms has shown that DDH-1 may prompt reactive oxygen species (ROS) generation, decrease the mitochondrial membrane potential (MMP), and stimulate DNA double-strand breaks (DSBs) in A549 cells. Study of the signal pathway has indicated that DDH-1 could activate JNK phosphorylation and inhibit ERK phosphorylation. Interestingly, NAC, which scavenges ROS, reversed the MMP decline, DNA damage, JNK phosphorylation activation, and ERK phosphorylation inhibition caused by DDH-1. Overall, these findings provide evidence that the eIF4E/eIF4G interaction inhibitors DDH-1 induces DNA damage and apoptosis in human lung cancer A549 cells.

Nimodipine (NMD), a calcium channel blocker, has demonstrated benefits in treating glaucoma. However, its ocular therapeutic application remains limited due to its poor aqueous solubility, which restrains the development of an ophthalmic formulation. Thus, the present study aimed to formulate an NMD micelle ophthalmic solution to enhance the potential of NMD in an ocular topical formulation to treat glaucoma. The NMD micelle ophthalmic solution was formulated with nanocarriers composed of rebaudioside A and d-α-tocopheryl polyethylene glycol 1000 succinate. Spherical mixed micelles were optimized and obtained at a small micelle size 13.429 ± 0.181 nm with a narrow size distribution (polydispersity index 0.166 ± 0.023) and high encapsulation efficiency rate (99.59 ± 0.09%). Compared with free NMD, NMD in micelles had much greater in vitro membrane permeability and antioxidant activity. The NMD micelle ophthalmic solution was well tolerated in rabbit eyes. It profoundly improved the in vivo intraocular permeation of NMD, and in vivo intraocular pressure reduction and improved miosis were also observed. Accordingly, this NMD micelle ophthalmic solution might be a promising ocular formulation to treat glaucoma.

Removal of low content of Cr(VI) from water is a critical challenge for water environment protection. Herein, an acrylamide-thiosemicarbazide cellulose aerogels (ATC) was designed by dissolving, grafting and freeze-drying to introduce thiosemicarbazide onto acrylamide-cellulose aerogels (AMC) via Schiff based reaction. The resultant ATC was further employed as an efficient adsorbent to remove low content of Cr(VI) from wastewater by adsorption and reduction. The SEM, FT-IR, and BET results showed that the ATC was composed of well-developed pore structure and owned functional groups such as –NH2, C–S and C=S groups. Experimental results indicated that ATC exhibited excellent removal efficiency for 99% under low initial concentration (0.1–10 mg/L). The adsorption isotherms demonstrated ATC adsorbent according to a monolayer adsorption behavior following the Langmuir model with a calculated maximum adsorption capacity of 83.40 mg/g at pH 3, and the adsorption kinetics well obeyed the pseudo-first-order kinetic model. Importantly, the maximum effluent concentration of Cr(VI) was lower than 0.045 mg/L, meeting the standard of WHO (50 μg/L). Furthermore, the main removal mechanisms involved the synergistic effect of electrostatic interactions, reduction and chelation between the positively charged functional groups of adsorbent and the anionic Cr(VI) ions.

The ever-increasing demands for low-cost, miniaturized, light-weight supercapacitors significantly enhance the standards of electrode materials. High capacitance and good rate performance at high mass loadings (>10 mg cm−2) are crucial for increasing the energy density of supercapacitors under the premise of high-power characteristic. However, most electrode materials show good performance only at a rather low mass loading. Increasing the electrode mass loading or thickness causes severely blocked electron and ion transport channels, decreased accessible active sites, as well as rapid fading of the capacitance and rate performance. The gap between the materials' theoretical and practical electrochemical performances drastically hinders their application. In this review, we summarize the design and preparation of high mass-loading carbon electrodes from the aspects of the entire conductive network and ion transport channels, dense structural design, and freestanding electrode construction. The basic electrochemical processes and kinetics, structure–property relationships, and new energy storage sites are discussed towards filling the gap between the new materials and practical applications. Finally, the future prospects, challenges, and promising strategies to solve the current problems are concluded to shed light on the development of high-performance practical carbon electrode materials.

Urban object segmentation and classification tasks are critical data processing steps in scene understanding, intelligent vehicles and 3D high-precision maps. Semantic segmentation of 3D point clouds is the foundational step in object recognition. To identify the intersecting objects and improve the accuracy of classification, this paper proposes a segment-based classification method for 3D point clouds. This method firstly divides points into multi-scale supervoxels and groups them by proposed inverse node graph (IN-Graph) construction, which does not need to define prior information about the node, it divides supervoxels by judging the connection state of edges between them. This method reaches minimum global energy by graph cutting, obtains the structural segments as completely as possible, and retains boundaries at the same time. Then, the random forest classifier is utilized for supervised classification. To deal with the mislabeling of scattered fragments, higher-order CRF with small-label cluster optimization is proposed to refine the classification results. Experiments were carried out on mobile laser scan (MLS) point dataset and terrestrial laser scan (TLS) points dataset, and the results show that overall accuracies of 97.57% and 96.39% were obtained in the two datasets. The boundaries of objects were retained well, and the method achieved a good result in the classification of cars and motorcycles. More experimental analyses have verified the advantages of the proposed method and proved the practicability and versatility of the method.

The contamination of Pb and Cr to the environment cannot be ignored. It is an urgent task to explore an efficient and cheap technique to treat Pb and Cr. Bentonite-sulfoaluminate cement composites (Bent-CSA) was prepared to solidify Pb2+ and Cr3+, and their leachability, setting time, and compressive strength were researched in this study. Then the hydration products were analyzed via XRD and SEM. The results show that Bent-CSA immobilized Pb2+ and Cr3+ efficiently, the compressive strength was slightly affected by Pb2+ and Cr3+, but that gradually decreased as bentonite content increased. Bent-CSA could be reused as foundation cushion and roadbed materials after solidifying Pb2+ and Cr3+.

This paper presents an accurate and effective method, namely, the improved artificial tree algorithm based on the Green’s kernel function method (IAT-GKFM), to identify the load in time domain. The forward problem of load identification is constructed by using the Green’s kernel function method. The forward problem is discretized using the time domain Galerkin method, where a matrix form for load identification is formed. The IAT algorithm is proposed to solve the inverse multi-dimensions problem in the inverse stage, which aims to minimize the measuring dispersion between the calculated response and the actual response. Several numerical examples are conducted. It is demonstrated that the IAT with high performance can provide more optimum results than those of other compared algorithms. Using this optimized strategy, the loads acting on a simple plate and a vehicle roof are reconstructed successfully. The superiority of IAT-GKFM may motivate the improvement of the other inverse problems.

Five flexible chain & rigid skeleton complementation polycarbazole networks P-Fo, PBT-C1 (C2, C4, C6) were designed and synthesized for gas storage. Increasing the length of alkyl groups from naked to –CH3 to –n-C6H12, the morphology (SEM) and thermostability (TGA) got tremendous changes. PBT-C1 exhibited Brunauer-Emmett-Teller (BET) specific surface area of 685 m2 g−1, which is larger than network P-Fo without TTF substitutions. Nevertheless, further replacing the alkyl-substituted TTF motifs with longer alkyl chains (PBT-C2, C4, C6) would bring a dramatic drop of BET surface areas to less than 100 m2 g−1, similar trends have found for H2, CO2, and CH4 adsorption as side chains changed. It need to be mention that decorating the alkyl group, CH4 adsorption enthalpy can be significantly improved to 52.1 kJ mol−1 (PBT-C4) at zero loading, indicating that alkyl segment can promote the adsorption potential between microporous and CH4 molecule, while have futile effect on H2 and CO2 molecule. These results demonstrated that rational flexible chain grafted into the rigid skeleton at one hand can block the microporous, but it will also have more beneficial on the BET surface areas, pore volume and gas adsorption ability, especially for methane.

The fishbone model is a simplified numerical model for moment-resisting frames that is capable of modelling the effects of column-beam strength and stiffness ratios. The applicability of the fishbone model in simulating the seismic responses of reinforced concrete moment-resisting frames of different sets of column-beam strength and stiffness ratios are evaluated through nonlinear static, dynamic and incremental dynamic analysis on six prototype buildings of 4-, 8- and 12-stories. The results show that the fishbone model is practically accurate enough for reinforced concrete frames, although the assumption of equal joint rotation does not hold in all cases. In addition to the ground motion characteristics and the number of stories in the structures, the accuracy of the model also varies with the column-beam stiffness and strength ratios. The model performs better for strong column-weak beam frames, in which the lateral drift patterns are better controlled by the continuous stiffness provided by the strong columns. When the inelastic deformation is large, the accuracy of the model may be subjected to large record-to-record variability. This is especially the case for frames of weak columns.

There have been limited studies on the hardening of cement containing different heavy metals owing to differences in solidification effect. The leachability, setting time, and compressive strength of sulfoaluminate cement (CSA) and ordinary Portland cement (OPC) mixed with different concentrations of Cr(NO3)·9H2O, Pb(NO3)2, Cd(NO3)2·4H2O solution were studied and the hydration products were analyzed using XRD and SEM. The results suggest that CSA immobilized Pb2+ and Cd2+ efficiently, while OPC solidified Cr3+ and Cd2+ well. Cd2+ prolonged the setting time of CSA and Pb2+ remarkably delayed that of OPC. There was only a slight influence of Cr3+, Pb2+, and Cd2+ on the compressive strength of CSA or OPC.

In order to prevent reflection cracking of composite pavement, the Hills formula, Goodman hypothesis, and ABAQUS software are used to carry out simultaneous dynamic modulus tests on composite pavement specimens. The temperature shrinkage stress formula for an asphalt surface considering stress relaxation is derived. The change rule for the accumulated temperature shrinkage stress of an asphalt surface layer with varying cooling range and cooling rate is obtained. The influences of different asphalt and concrete layer thicknesses on the temperature shrinkage stress at the asphalt layer bottom joint are obtained considering the influence of concrete shrinkage on the temperature stress at the asphalt layer bottom joint.

In order to study what the effect of superplasticizers on the setting time, fluidity and compressive strength of calcium sulfoaluminate cement (CSA) a naphthalene-based superplasticizer (BNS) and a polycarboxylic acid superplasticizer (PC) were selected to interact with CSA pastes and ye’elimite, respectively. X-ray diffraction (XRD), thermogravimetric (TG) analysis and scanning electron microscopy (SEM) analytical methods were used to investigate the class, amount and microstructure of the CSA pastes and ye’elimite pastes hydration products under the effect of the superplasticizers. The results showed that the addition of BNS can promote ettringite generation and thus improve the early compressive strength. As the addition of BNS increased from 0.8 wt% to 2.0 wt%, the initial setting time was prolonged 10 min, the final setting time was prolonged 7 min, the 5 min fluidity was improved from no fluidity to 220 mm. However, as the addition of PC increased from 0.08 wt% to 0.20 wt%, the setting time of the PC just changed within 3 min, the 5 min fluidity increased from 110 mm to 195 mm and no 15 min fluidity at all was observed. AS seen by SEM, it can be stated that generated ettringite under the addition of PC was layered and lacking bonding, and its morphology changed from rod-like to flake-like, leading to a decrease in early compressive strength.

To formulate a xanthan gum–containing linezolid ophthalmic solution (LZD-XG) as a new antibiotic treatment against ocular bacterial infection. LZD-XG was prepared and evaluated for its in vitro/in vivo ocular tolerance, in vitro/in vivo antibacterial activity, and in vivo ocular penetration. The optimized LZD-XG exhibited good in vitro/in vivo eye tolerance. A prolonged ocular surface residence time of LZD-XG was observed after topical instillation, and the ocular permeation was significantly better for LZD-XG than fora linezolid (LZD) ophthalmic solution. The in vitro antimicrobial activity was significantly better with LZD-XG than with LZD. In vivo evaluation also confirmed a strong therapeutic treatment effect of LZD-XG, as it significantly improved the clinical symptoms, ameliorated the damage of Staphylococcus aureus to ocular tissues, lowered the colony forming unit counts in the cornea, and decreased the myeloperoxidase activity in the cornea. LZD-XG was deemed a viable ophthalmic solution against ocular bacterial infection due to its excellent in vitro and in vivo characterizations.

Honokiol (HK) has a variety of biological activities, but its poor solubility limits its application. Rebaudioside A (RA) is able to self-assemble into micelles, which can be used for oral delivery of anticancer drugs. This study aims to create and evaluate a nano-sized anticancer drug delivery system based on RA, as RA micelles are thought to strengthen the therapeutic effects of HK. The results showed that RA and HK can be formulated into self-assembling micelles (RA-HK) with a size of 4.356 ± 0.142 nm and uniform distribution (PDI = 0.1906 ± 0.0184). Moreover, RA-HK could enhance the antitumor activity of HK in vitro. Further, it was shown that RA-HK can induce G0/G1 cycle arrest, apoptosis, and reactive oxygen species (ROS) generation in HuH-7 cells. The results for this mechanism indicate that RA-HK can induce DNA damage as well as changes in cycle and apoptotic-related proteins and activate the ERK signaling pathway. The in vivo antitumor results showed that RA-HK could also enhance the antitumor activity of HK in mice and does not induce any side effects. The pharmacokinetic results illustrate that RA-HK can increase the oral bioavailability of HK that and RA-HK is widely distributed in rats. Taken together, the above results prove that RA is a novel oral nano-drug delivery system with great potential for the delivery of hydrophobic antitumor drugs, such as HK.

Tea saponin (TS), a plant derived biosurfactant, was used to investigate on its effectiveness on the extraction of three typically selected rare earth elements (REEs, light lanthanum (La), medium arrowhead (Dy) and heavy erbium (Er)) from contaminated soils, in the presence of important toxic heavy metals (lead (Pb) and cadmium (Cd)). A complete procedure, involving the extraction of REEs in soils, the recovery of REEs and TS in the extraction leachates and the reuse of the recovered TS, was established. Experimental results showed that the optimal extraction parameters were consumption of 1.2 g/g (TS/soil), pH of 5 and the extraction time of 24 h. The recovery efficiencies of La, Dy, Er, Cd and Pb achieved 96.9%, 88%, 84.3%, 88% and 91.1% using 0.3 g/g (Ca(OH)2/soil). The overall extraction efficiencies of La, Dy, Er, Cd and Pb were 53.9%, 73.2%, 71.7%, 95.9% and 38.8% by three times using the recovered TS solution. The extractable fractions of La, Dy, Er, Cd and Pb in soil were found to be highest in their acid soluble and reducible forms. Mechanisms studies indicated the increased binding strength (IR) and the decreased mobility (MF) of REEs and metals after the flushing with TS. Carboxyl groups in TS were attributed to the formation of complexation and agglomeration between TS and studied REEs and other metals, confirmed by the analysis of both the X-ray photoelectron spectroscopy (XPS) and the dynamic light scattering (DLS). This study established an environmentally-friendly contaminated soil remediation and the recovery of valuable REEs by the combination use of TS and calcium hydroxide.

This study aims to create and evaluate a kaempferol (KAE) ophthalmic solution based on polyvinylpyrrolidone (PVP) nanocomplexes. KAE can be highly complexed with PVP K-17PF (17PF) to formulate an aqueous ophthalmic solution named 17PF-KAE. The optimized 17PF-KAE displays high complexing efficiency, an ultra-small size (8.628 ± 0.066 nm), and good aqueous dispersibility. 17PF-KAE did not show any obvious cytotoxicity or in vivo ocular tissue toxicity. Further, 17PF-KAE was observed to facilitate significant improvement in in vitro parallel artificial membrane permeability, in vitro cellular uptake, and ex vivo corneal permeation of KAE. Regarding the in vivo ocular absorption test, the KAE levels in the cornea and aqueous humor determined from the 17PF-KAE group were much higher than those in the free KAE solution group in addition to conjunctiva and the iris-ciliary body at certain time points. 17PF-KAE was also observed to promote remarkable improvement in in vitro antioxidant activity and in vivo anti-inflammatory activity. Moreover, a topical 17PF-KAE solution in mice eyes showed significant improvement in the treatment efficacy of corneal alkali burns over the free KAE solution. The therapeutic mechanism was also associated with inhibiting the production of key mediators of inflammation (CD54, IL-6, and TGF-β1) and angiogenic factors (VEGF). Therefore, these results demonstrate that 17PF-KAE may be a promising new ophthalmic formulation for the prophylaxis and treatment of oxidative stress and inflammation-related ocular diseases.

Pavement performance prediction is a crucial issue in big data maintenance. This paper develops a hybrid grey relation analysis (GRA) and support vector machine regression (SVR) technique to predict pavement performance. The prediction model can solve the shortcomings of the traditional model including a single consideration factor, a short prediction period, and easy overfitting. GAR is employed in selecting the main factors affecting the performance of asphalt pavement. The SVR is performed to predict the performance. Finally, the data collected from the weather station installed on Guangyun Expressway were adopted to verify the validity of the GRA-SVR model. Meanwhile, the contrast with the grey model (GM (1, 1)), genetic algorithm optimization BP[[parms resize(1),pos(50,50),size(200,200),bgcol(156)]]081%, −0.823%, 1.270%, and −4.569%, respectively. The study concluded that the nonlinear and multivariate prediction model established by GRA-SVR has higher precision and operability, which can be used in long-period pavement performance prediction.

We reported a facile two-step hydrothermal procedure to prepare zinc-cobalt oxide and sulfide hybrid nanoclusters (ZCOSH NCs), initialized by the synthesis of metal oxides and followed by the partial substitution of oxygen with sulfur. Benefiting from their morphological features and partial substitution with sulfur, both the electrical conductivity and further the actual specific capacitance of ZCOSH NCs were apparently improved compared to zinc-cobalt binary oxide nanosheets (ZCO NSs). Moreover, its cycling stability has also been significantly enhanced. Its excellent specific capacitance achieved 2176.7 F g−1 at 1 A g−1, which was six times larger than ZCO NSs (367.2 F g−1 at 1 A g−1). Moreover, a hybrid supercapacitor was assembled using ZCOSH NCs as its positive electrode and the activated carbon as its negative electrode. This hybrid supercapacitor device presented a higher specific capacitance value of 116.3 F g−1 at 1 A g−1 with corresponding specific energy of 41.4 W h kg−1 at a specific power of 801.3 W kg−1, and a superior cycling stability after 3000 charge-discharge cycling tests. This study confirmed the feasible and unique synthesis approach to balance the higher capacitance of oxides and the higher electric conductivity of sulfides within this binary ZCOSH NC.

This study aims at developing an easy-to-apply strengthening method for reinforced concrete (RC) short columns by using Engineered cementitious composite (ECC), which is a high-performance composite material with tensile strain-hardening behavior and multiple cracking mechanism in tension. Seven identical RC short columns were prepared, and five of them were strengthened with ECC jackets or ferrocement jacket. The main experimental parameters involve the jacketing schemes and the axial load. The failure modes, hysteresis response, deformation capacity, stiffness degradation and energy dissipation capacity of the specimens were studied by the lateral cyclic loading tests. The tests results show that the ECC jacketed columns failed in ductile modes, and exhibited significant improvement in plastic deformation ability and energy dissipation capacity compared with the control specimens. At the ultimate displacement point, the increase of the drift ratio and cumulative energy dissipation of the ECC jacketed columns were 19–111% and 102–549%, respectively, compared with the corresponding control specimens. Under higher axial loads, the ECC jacketing was still certified to be effectively in enhancing the seismic behavior of the original columns. The shear deformation and the shear strength of the original RC columns were effectively improved by the external ECC jacket, and a prediction method for the shear strength of the ECC jacketed columns was given based on the current Chinese codes.

The chemical reactions of hydrogen gas generation via water splitting on Si-terminated 4H-SiC surfaces with or without C/Si vacancies were studied by using first-principles. We studied the reaction mechanisms of hydrogen generation on the 4H-SiC(0001) surface. Our calculations demonstrate that there are major rearrangements in surface when H 2 O approaches the SiC(0001) surface. The first H splitting from water can occur with ground-state electronic structures. The second H splitting involves an energy barrier of 0.65 eV. However, the energy barrier for two H atoms desorbing from the Si-face and forming H 2 gas is 3.04 eV. In addition, it is found that C and Si vacancies can form easier in SiC(0001)surfaces than in SiC bulk and nanoribbons. The C/Si vacancies introduced can enhance photocatalytic activities. It is easier to split OH on SiC(0001) surface with vacancies compared to the case of clean SiC surface. H 2 can form on the 4H-SiC(0001) surface with C and Si vacancies if the energy barriers of 1.02 and 2.28 eV are surmounted, respectively. Therefore, SiC(0001) surface with C vacancy has potential applications in photocatalytic water-splitting.

Many new bio-inspired algorithms are recently being proposed, artificial tree (AT) algorithm, inspired by the growth of trees and the update behavior of branches, is one of them. There are also some improved AT algorithms being proposed to improve their calculation accuracy. However, the main challenges of AT algorithms lie in the insufficiencies in the design of update operators as well as the position interaction between branches and the capture of key information and the performance of AT algorithms needs to be enhanced. This work proposes an improved AT algorithm with two populations (IATTP). In IATTP, the update strategies of branches are redesigned, and a variety of efficient update operators are designed and applied. The branch population is changed from one to two, and the competition mechanism between populations is proposed. Through the migration of branches between populations, the scale of population with better efficiency is expanded and the size of population with lower efficiency is reduced, thus a reasonable interaction between populations and branches is realized. With above strategies, the efficiency and accuracy of IATTP are significantly improved. The results of IATTP are proved to be advantageous when the performance of IATTP is compared with AT algorithm, improved artificial tree (IAT) algorithm and feedback artificial tree (FAT) algorithm through typical test problems. Meanwhile, the results of IATTP in current state are also preferable when IATTP is compared with other improved algorithms in high dimensional problems. The experimental results prove that IATTP is competitive in solving optimization problems.

Improving energy efficiency of electrocatalytic and photocatalytic CO2 conversion to useful chemicals poses a significant scientific challenge. We report on using a colloidal nanographene to form a molecular complex with a metal ion to tackle this challenge. In this work, a well-defined nanographene–Re complex was synthesized, in which electron delocalization over the nanographene and the metal ion significantly decreases the electrical potential needed to drive the chemical reduction. We show the complex can selectively electrocatalyze CO2 reduction to CO in tetrahydrofuran at −0.48 V vs NHE, the least negative potential reported for a molecular catalyst. In addition, the complex can absorb a significant spectrum of visible light to photocatalyze the chemical transformation without the need for a photosensitizer.

Three microporous polythiophenes, P-TTT, P-THIDT and P-DTBDT, with increasing rigidity of their cores were designed and prepared by FeCl3 catalyzed polymerization. The step by step strengthening of the rigidity of these polymers, stacking morphologies (planar, three-dimensional mesh pattern, and spherical), and Brunauer–Emmett–Teller (BET) surface areas have been extensively improved (thienyl core is 58 m2 g−1, phenyl core is 869 m2 g−1 and BDT fused ring is 1140 m2 g−1). At the same time, the carbon dioxide uptake capacity has been enhanced from 2.1 wt% to 12.1 wt% at 1.1 bar and 273 K temperature, accompanied by an increase of the heat adsorption from 17 to 37 kJ mol−1. Molecular-level models were developed that showed the same trend, which was similar to the experimental results. The rational skeletal rigidity can counteract the nanostructural packing and avoid the nanopores collapsing in organic microporous polymers.

Polyvinylpyrrolidone (PVP) is capable of forming complexes in aqueous solutions with poorly soluble drugs, dramatically increasing their aqueous solubility and formulating stable aqueous solutions. These self-assembled complexes could potentially be explored as an ocular drug delivery system. This study assumes that these PVP medicine complexes can improve ocular permeation and strengthen the drugs’ therapeutic effects. PVP K-17PF (17PF) and naringenin (NAR) could formulate into self-assembly nanocomplexes (17PF-NAR). The optimal formulation featured a 17PF/NAR weight ratio 20:1 with a complexation efficiency of 98.51 ± 0.86 percent, a mean diameter 6.73 ± 0.42 nm, and a polydispersity index 0.254 ± 0.019. This 17PF-NAR nanocomplex ophthalmic solution was stable in well storage at both 4° and 25 °C for 12 weeks. The 17PF-NAR nanocomplexes were observed to significantly improve in vitro antioxidant activity and membrane permeation of NAR. The 17PF-NAR nanocomplex ophthalmic solution had good in vitro cellular tolerance and well in vivo tolerated in rabbits. The 17PF-NAR nanocomplexes also demonstrated significant improvement in in vivo intraocular permeation of NAR and in vivo anti-inflammatory efficacy. These results indicated that nanocomplexes based on 17PF have great potential as novel nanoformulations to improve the ocular bioavailability and therapeutic efficacy of poorly water-soluble agents such as NAR.

In this work, a solid polymer electrolyte (SPE) doped with carbon nanotubes (CNTs) was used as a gas sensing material for a NO2 gas sensor. The electrolytes consisted of the ionic liquids (ILs) and CNTs, which were immobilized in a poly(vinylidene fluoride) (PVDF) matrix. The SPE membranes were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), and cyclic voltammetry (CV). The experimental results show that the addition of an appropriate amount of CNTs can appropriately improve the electrochemical performance of the SPE membrane. It was shown that NO2 gas sensors with an appropriate amount of CNTs added to their SPEs had a higher gas sensitivity than those with SPE containing no CNTs. When the mass ratio of PVDF, N-methyl-2-pyrrolidone (NMP), IL, and CNT was 1:4:1:0.08, the SPE showed the best gas sensitivity, and its sensitivity is 0.00275 V/ppm.

A noble, safe and electrochemically stable microporous IL-CNTs-PANI polymer electrolyte has been reported. In the microporous polymer electrolyte (MPE), polyvinylidene fluoride (PVDF) was doped with an ionic liquid (IL), carbon nanotubes (CNTs) and polyaniline (PANI). The surface structure and element composition of MPE film were measured by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and fourier-transform infrared spectroscopy (FTIR). The thermogravimetric analysis/differential scanning calorimetry (TGA/DSC) have carried out to characterize electrolytes’ thermal stability, and the electrochemical performance was measured by cyclic voltammetry (CV) and Tafel curves. It is found that a soft and porous MPE film can be obtained by changing the content of CNTs/PANI and the heat treatment temperature. Doping with different amounts of PANI has certain effects on the thermal stability and crystallization properties of MPE film. The prepared electrolyte membrane has good capacitance, wide electrochemical window (~3 V), certain charge transfer and ionic conductivity. Finally, the prepared electrolyte membrane was used to print a NO2 gas sensor, which proved that the MPE has the potential to become a gas-sensing material for NO2 sensors.

The Northwestern Sichuan Basin is a hot spot for natural gas exploration, and in recent years, many wells have obtained high-yield commercial gas flows in the Qixia Formation. However, due to the influence of foreland orogeny, the oil and gas in the Qixia Formation often have the characteristics of multisource filling, multistage accumulation and multistage transformation, which results in an unclear understanding of the gas source and the accumulation process. This paper uses the concept of sub-block research through carbon isotope and biomarkers analyses, to carry out gas-gas, gas-source and bitumen-source rock comparisons in different structural belts to determine the natural gas sources. On this basis, basin simulation and fluid inclusion analysis technology are used to determine the stage of hydrocarbon accumulation, and then the accumulation process is determined. Studies have shown that the gas source of the Qixia Formation are different in the different structural belts: (1) The natural gas from the Qixia Formation in the thrust nappe belt mainly originates from the Qiongzhusi Formation source rock; (2) The natural gas from the Qixia Formation in the hidden fault belt is a mixture of the source rock of the Qixia Formation and the source rock of the Qiongzhusi Formation; and (3) The natural gas from the Qixia Formation in the gentle belt mainly originates from the Middle Permian source rock and the Upper Permian Longtan Formation source rock. The Indosinian, Yanshania, and Himalayan movements all have great influence on the formation of the Qixia Formation reservoir in northwestern Sichuan, and the accumulation process of the different structural belts is quite different, but generally, the accumulation process of the different structural belts have experienced three stages: a primary oil pool stage, gas pool stage and reformation and definition stage.

The successful fabrication of the lateral heterostructures (LHSs) open a promising avenue for the band structure engineering. Here, we design novel (C3N)2(C3B)2 LHSs integrating monolayer C3N and C3B along different directions and predict their electronic properties based on the density functional theory. It is found that (C3N)2(C3B)2 LHSs stitched semi-infinite monolayers along both armchair and zigzag directions exhibit excellent stability. Remarkably, the band structures of both armchair-(C3N)2(C3B)2 and zigzag-(C3N)2(C3B)2 LHSs undergo an indirect to direct transition, by contrast, both pristine C3N and C3B monolayers are indirect band gap semiconductors. The type-II band alignment in the zigzag-(C3N)2(C3B)2 has been revealed. In addition, the tensile strain can effectively modulate the band structures. Especially, the band of zigzag-(C3N)2(C3B)2 is reversed under the tensile strain along the zigzag direction.

High-performance porous carbon is an essential electrode materials for high-specific energy supercapacitors because it has a high specific surface area on the electrode surface and stores charge through electrolyte-ion adsorption. In this article, N, S co-doped porous carbon was successfully prepared through carbonization and activation of partial poly (2, 2′-dithiodianiline) (PDTDA). The N, S co-doped porous carbon material was used to prepare the electrode for supercapacitor. The three-electrode system was used to test its electrochemical performance. The results show that the suitable carbonization temperature was 600 °C (ASNC-600–800), which showed excellent capacitance performance. The specific capacitance of ASNC-600–800 is 500.10 F/g at 1 A/g. In addition, N, S co-doped porous carbon possess the specific energy of 21.15 Wh/kg at specific power of 450 W/kg. A new path has been opened for the preparation of low cost and high-performance porous carbon electrode materials.

Phosphate rock (PR) and ferric salts have been frequently used to immobilize heavy metal(loid)s in soils, but in varied efficiencies referring to different metal(loid) pollutants. This study explored the effective application of plant ash (PA) to the previous formula of phosphate rock (PR) and ferric salts (Fe(NO3)3) (PR + Fe3++PA), compared to only PR, on the bioavailability and immobility of multi-metal(loid)s of selected arsenic (As), lead (Pb) and cadmium (Cd) in soils. Results from NaHCO3- extraction and toxicity characteristic leaching procedure (TCLP) implied the increase of the As mobility in soils by 7.0% and 2.6% using PR only, but the significant reduction of the As mobility by 24.2% and 82.4% jointly using PR + Fe3++PA. Meanwhile, the application of either PR alone or PR + Fe3++PA in soil significantly decreased Pb and Cd extracting in diethylene triamine pentacetate acid (DTPA) and TCLP, particularly, the immobilization effect of PR + Fe3++PA was better than that of PR. The leaching column test further confirmed the high durability of PR + Fe3++PA on the immobilization of As and Pb under the continuous acid exposure, but likely slightly increased the mobility of Cd (the accumulated concentration of Cd, 5.88 μg/L) compared to that (3.16 μg/L) in the untreated column (UN-column), which were both much lower than the level V (100 μg/L) of the Chinese National Quality Standard for Surface Water (GB 3838–2002). Therefore, PR + Fe3++PA exhibited the significant enhancement on the immobilization of As, Pb and Cd under simulated acid rain (SAR) leaching.

To accurately evaluate pore structure and gas content characteristics of shale reservoir, a series of tests, including XRD, TOC, porosity, FE-SEM, N2 and CO2 adsorption, and high-pressure methane sorption, were conducted on the Wufeng-Longmaxi shale in the Fuling area. The principal objective of this work is to reveal the development mechanisms of shale pores, and quantitatively calculated both free gas and absorbed gas contents in different lithofacies. A total of three main lithofacies, i.e., clay-rich siliceous shale lithofacies (S-3), argillaceous/siliceous mixed shale lithofacies (M-2) and silica-rich argillaceous shale lithofacies (CM-1) were identified in the study area. The highest values of TOC, helium porosity, pore volume, and specific surface area are recognized in the S-3 shales, with a mean of 3.94%, 5.12%, 22.13 × 10−3 cm3/g, and 35.23 m2/g, respectively. The pore volume and specific surface area of S-3 shales are primarily contributed by OM pores, with an average proportion of 66.99% and 66.38%. However, the pore volume and specific surface area of clay-related pores, a significant component of CM-1 shales, occupied an average of 64.30% and 52.72%, respectively. Owing to the change of lithofacies from S-3 to M-2 and CM-1 shales, the pore volume is reduced by 28.74% and 22.37%, while the specific surface area is reduced by 30.28% and 32.89%, respectively. The total shale gas contents of S-3 shales are calculated to be 5.54–7.72 m3/t, with an average of 6.64 m3/t, and that of M-2 shales and CM-1 shales are ranging from 4.28 m3/t to 5.03 m3/t and 2.43 m3/t to 4.33 m3/t, with a mean of 4.61 m3/t and 3.51 m3/t, respectively. However, due to the difference of pore types, the CM-1 shales are characterized by the highest proportion of free gas (average 59.08%), whereas that of M-2 shales and S-3 shales are recognized with 54.96% and 50.93%, respectively.

In this work, we systematically investigate the structures, electronic and optical properties of monolayer C3N doped with B (C3N1-xBx, x = 0, 12.5%, 25%, 37.5%, 50%, 62.5%, 75%, 87.5% and 100%) by using first-principles method. The B doping C3N monolayers still maintain hexagonal planar configuration with the increasing of B content. Both C3N monolayer and C3B monolayer are indirect semiconductors. B doped C3N monolayer undergoes a transition from indirect band gap to direct band gap at x = 25%, 50% and 87.5%. In addition, the bandgap of C3N can be effectively mediated via B doping. Meanwhile, the mechanisms of B doping effects on the electronic structures of C3N are analyzed. The B doping C3N exhibits main absorption peak in ultraviolet region and the secondary peak is in visible light region. Furthermore, the ratio of ultraviolet and visible lights can be effectively engineered by the B concent.