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CO2 capture and utilization (CCU) is an effective strategy to mitigate global warming. Absorption, adsorption and membranes are methods used for CO2 separation and capture, and various catalytic pathways have also been developed for CO2 utilization. Although widely researched and used in industry, these processes are energy-intensive and this challenge needs to be overcome. To realize further optimization, novel materials and processes are continuously being developed. New generation materials such as ionic liquids (ILs) have shown promising potential for cost-effective CO2 capture and utilization. This study reviews the current status of ILs-based solvents, adsorbents, membranes, catalysts and their hybrid processes for CO2 capture and utilization. The special properties of ILs are integrated into new materials through hybridization, which significantly improves the performance in the process of CCU.

In this paper, the problem of fixed-time synchronization is investigated for a class of delayed complex dynamical systems with stochastic perturbation. Novel impulsive pinning controllers are proposed for the complex networks to be stochastic fixed-time synchronization in probability. Time delays, stochastic perturbation and impulsive control schemes are all taken into consideration, which make the model more general. The fixed-time synchronization is carried out based on impulsive control technique and stochastic analysis method. Sufficient conditions are proposed to ensure the fixed-time synchronization of the error systems of the stochastic complex dynamical networks. In addition, the settling time function is estimated, which is independent on the initial value. An example is given to illustrate the effectiveness of the theoretical results.

In this study, we consider the fixed-time synchronization problem for stochastic memristor-based neural networks (MNNs) via two different controllers. First, a new stochastic differential equation is established using differential inclusions and set-valued maps. Next, two kinds of control protocols are designed, including a nonlinear delayed state feedback control scheme and a novel adaptive control strategy, by which fixed-time synchronization of MNNs can be achieved. Then based on stochastic analysis techniques and a Lyapunov function, some sufficient criteria are obtained to ensure that stochastic MNNs achieve stochastic fixed-time synchronization in probability. In addition, the upper bound of the settling time is estimated. Finally, simulation results are provided to demonstrate the validity of the proposed schemes.

Acid gases, especially sulfur dioxide (SO2), released from the burning of fossil fuels, have made a great contribution to environmental pollution. However, the technologies to remove the acid gases...

Rheumatoid arthritis (RA) is a chronic, systemic, progressive autoimmune disease. The vascular permeability of inflamed joints in RA makes it a natural candidate for passive targeting, similar to the enhanced permeability and retention (EPR) effect in solid tumors. Thus, various therapeutic drugs have been encapsulated in nanocarriers to achieve longer in vivo circulation times and improve RA targeting. Although liposomes are the most widely used nanocarriers for RA treatment, the effects of physical and chemical characteristics of liposomes, such as particle sizes, surface charge, polyethylene glycol (PEG) chain length, and PEG concentration, on their passive RA targeting effect have not been fully elucidated. Here, we systematically investigated the effects of physical and chemical properties of liposomes on circulation time and conducted preliminary studies on their passive targeting mechanisms. A series of liposomes with different particle sizes (70, 100, 200, and 350 nm), surface charges (positive, negative, slight positive, and slight negative), PEG chain lengths (1, 2, and 5 kDa), and concentrations (5, 10, and 20% w/w of total lipid) were prepared by lipid film dispersion and extrusion. The pharmacokinetics of liposomes with different formulas were evaluated with a fluorescence microplate reader. A collagen-induced arthritis (CIA) mouse model was utilized to mimic RA pathological conditions and to evaluate the targeting and efficacy of liposomes with different properties using a near-infrared fluorescence imaging system. Uptake of fluorescent liposomes by various synovial cells was measured by flow cytometry. The results indicated that liposomes with 100 nm diameter, a slight negative charge, and 10% incorporation of 5 kDa PEG had better in vivo circulation time and inflamed joint targeting than did other liposomes. Dexamethasone (Dex) was encapsulated into optimized liposomes as an active ingredient for RA treatment. Pharmacodynamic studies demonstrated that Dex liposomes could significantly improve the antiarthritic efficacy of Dex in a CIA mouse model of RA. This study also found that the retention mechanism of RA was mainly increased because of the uptake of liposomes by fibroblasts and macrophages in inflamed joints. This study provides a persuasive explanation for passive RA targeting by liposomes and advances our ability to treat RA with nanomedicine.

Deep eutectic solvents (DES) are generally composed of two or three cheap and safe components that are associated with each other via hydrogen bonds. The formation Caprolactam (CPL)-tetraalkyl ammonium halide (TAAX) DES and its hydrate were investigated using React IR. TAAX was introduced to CPL in the molten state at 353.15 K, the intermolecular H-N-C=O⋯H-N-C=O hydrogen bonds (CPL dimer) transfer to X−⋯H-N-C=O (CPL-TAAX DES). When water was added to CPL-TAAX DES, intermolecular X−⋯H-N-C=O⋯H-O-H hydrogen bonds appeared, and CPL-TAAX DES hydrate was formed. However, if the ratio of water exceeded the moral fraction of 0.61, CPL-TAAX DES hydrate turned into a CPL-TAAX aqueous solution. The C O (1660 cm−1) bonds were linearly correlated with hydrogen bonds number and TBAB amount in CPL-TBAB DES. When the molar fraction of CPL-TBAB DES was 0.39 to 0.78, the C O peak redshift has a better linear correlation with water. Halide anions and the alkyl chain length of TAAX have little influence on the redshifts and peak intensity of the C O peak.

Electrical resistance tomography (ERT) method is proposed to visually investigated of the defect in cementitious materials. Specimens with one precast defect are made with different water-cement (w/c) ratio and detected using the embedded electrodes. The experimental images are assessed with a similarity evaluation method based on color histogram. In addition, the electrical resistivity and moisture content of the specimens are measured simultaneously to explore its effects on the quality of the imaging results. The results show that the moisture content is the main factor influencing the resistivity of the specimens in the early hydration reaction while the w/c ratio becomes the main factor effecting the resistivity after the early hydration reaction. For the multi-defect detecting, the influence of electrical soft field effect cannot be neglected. The experiment results imply that ERT technique has potential in defect detection and in-situ monitoring in cement mortar.

With the number of bridges increases, the bridge health monitoring (BHM) technique is developing from single bridge monitoring to collaborative supervision of bridge group. Therefore, there are many technical problems need to be solved especially the performance evaluation index for bridge group network. This paper analyses the performance evaluation index of the bridges and bridge group network, establishes the performance evaluation index for bridge group based on rating factor (RF) and technical condition evaluation index. Based on bridge field testing and monitoring data, bridge technical condition evaluation index and performance evaluation method for bridge group are proposed. A case study demonstrates that the research results provide support for bridge group networking monitoring and collaborative supervision.

Binary neural network (BNN) has shown great potential to be implemented with power efficiency and high throughput. Compared with its counterpart, the convolutional neural network (CNN), BNN is trained with binary constrained weights and activations, which are more suitable for edge devices with less computing and storage resource requirements. In this paper, we introduce the BNN characteristics, basic operations and the binarized-network optimization methods. Then we summarize several accelerator designs for BNN hardware implementation by using three mainstream structures, i.e., ReRAM-based crossbar, FPGA and ASIC. Based on the BNN characteristics and hardware custom designs, all these methods achieve massively parallelized computations and highly pipelined data flow to enhance its latency and throughput performance. In addition, the intermediate data with the binary format are stored and processed on chip by constructing the computing-in-memory (CIM) architecture to reduce the off-chip communication costs, including power and latency.

Based on the multi-agent system model over switching network with random communication delay, we propose a distributed multi-step subgradient random projection algorithm and analyze the convergence and convergence rate of the proposed algorithm. The multi-step subgradient of agents is a combination of the subgradient at current time and all the historical subgradient. Batch random projection is utilized in proposed algorithm to improve the accuracy of random projection. To simplify the process of convergence analysis we propose a method of system expansion to replace the random communication delay. The final numerical simulation results show that the multi-step subgradient random projection algorithm has a faster convergence speed than the traditional subgradient algorithm.

Highlights A ginsenoside Rh2-based multifunctional liposome system (Rh2-lipo) was innovatively developed.Rh2-lipo not only innovatively challenges the position of cholesterol as a liposome component, but also provides another innovative potential system with multiple functions for anti-cancer drug delivery. Electronic supplementary material The online version of this article (10.1007/s40820-020-00472-8) contains supplementary material, which is available to authorized users., Liposomes hold great potential in anti-cancer drug delivery and the targeting treatment of tumors. However, the clinical therapeutic efficacy of liposomes is still limited by the complexity of tumor microenvironment (TME) and the insufficient accumulation in tumor sites. Meanwhile, the application of cholesterol and polyethylene glycol (PEG), which are usually used to prolong the blood circulation and stabilize the structure of liposomes respectively, has been questioned due to various disadvantages. Herein, we developed a ginsenoside Rh2-based multifunctional liposome system (Rh2-lipo) to effectively address these challenges once for all. Different with the conventional ‘wooden’ liposomes, Rh2-lipo is a much more brilliant carrier with multiple functions. In Rh2-lipo, both cholesterol and PEG were substituted by Rh2, which works as membrane stabilizer, long-circulating stealther, active targeting ligand, and chemotherapy adjuvant at the same time. Firstly, Rh2 could keep the stability of liposomes and avoid the shortcomings caused by cholesterol. Secondly, Rh2-lipo showed a specifically prolonged circulation behavior in the blood. Thirdly, the accumulation of the liposomes in the tumor was significantly enhanced by the interaction of glucose transporter of tumor cells with Rh2. Fourth, Rh2-lipo could remodel the structure and reverse the immunosuppressive environment in TME. When tested in a 4T1 breast carcinoma xenograft model, the paclitaxel-loaded Rh2-lipo realized high efficient tumor growth suppression. Therefore, Rh2-lipo not only innovatively challenges the position of cholesterol as a liposome component, but also provides another innovative potential system with multiple functions for anti-cancer drug delivery. Electronic supplementary material The online version of this article (10.1007/s40820-020-00472-8) contains supplementary material, which is available to authorized users.

Liposomes have been widely used for targeted drug delivery. However, nonselective distribution, low blood-brain barrier penetration, and the disadvantages of cholesterol greatly limit the application of conventional liposomes in the treatment of brain tumors. In the present study, we aimed to develop a multifunctional ginsenoside Rg3-based liposomal system (Rg3-LPs). Compared to cholesterol liposomes (C-LPs), Rg3-LPs not only significantly improved cellular uptake and penetration across glioma spheroids in vitro, but also remarkably enhanced active glioma targeting and intratumoral diffusion capability in vivo. Paclitaxel-loaded Rg3-LPs (Rg3-PTX-LPs) exhibited a substantially stronger anti-proliferation effect on C6 glioma cells than paclitaxel-loaded C-LPs and re-educated tumor-associated macrophages from the protumor M2 phenotype to the antitumor M1 phenotype in vivo. Rg3-PTX-LPs significantly prolonged median survival time of intracranial C6-bearing mice/rats by activating the immune microenvironment in glioma, facilitating T-cell immune responses with expansion of the CD8+ T-cell population, increasing the M1/M2 ratio, and decreasing regulatory T and myeloid-derived suppressor cells. Together, the results demonstrated that ginsenoside Rg3 is a good alternative for cholesterol in drug delivery liposomes and has a synergistic effect with loaded anticancer drugs. Rg3-PTX-LPs can serve as a multifunctional potential drug for the treatment of glioma.

CO2 released from fossil fuels has made a great contribution to global warming, and natural deep eutectic solvents (NADES) offer an attractive option for greening CO2 capture. Being economical natural materials, L-arginine (L-Arg) and glycerol (Gly) were used to synthesize a series of novel hydrophilic NADES (L-Arg/Gly, at mole ratios of 1:4, 1:5, 1:6, 1:7, 1:8). The L-Arg/Gly (1:6) DES showed excellent thermal stability (Tmax, 250 °C; Tf, 13.7 °C). The hydrates of L-Arg/Gly DES (at water contents of 0 wt%, 10 wt%, 20 wt%, 30 wt%, 40 wt%, 50 wt%, 60 wt%) were also prepared. The synthesis process of L-Arg/Gly DES and its hydrate were studied with FT-IR and in situ IR spectroscopy. High hydrophilicity of such solvent was demonstrated with fast and efficient capture of CO2 at a high absorption (0.511 mol CO2/mol NADES) under optimized conditions. In the gas-liquid absorption process, the hydrophilic properties of L-Arg/Gly DES and its hydrate greatly reduced the transfer barrier, and accelerated the phase transfer by increasing accessibility of active amine sites on NADES and CO2. And the dynamics for the CO2 absorption was investigated correspondingly. The absorption behaviors of CO2 in L-Arg/Gly DES and its hydrate were studied by in situ IR spectrometer and nuclear magnetic resonance (1H NMR, 13C NMR), and the characteristic infrared peaks and shifts of CO2 absorption were observed. In addition, the L-Arg/Gly DES could be reused for 5 times without obvious inactivation. Indicating the L-Arg/Gly DES would be a potential substitute of the traditional volatile amine solvents for CO2 capture.

Hydrological and geochemical changes have been studied extensively in China for the purpose of earthquake prediction since 1966. This paper gives a brief overview of the findings, which have been reported mainly in Chinese so far. Parameters studied include water level; water temperature; and radon, hydrogen and mercury concentrations. Significant changes have been observed before some large or even intermediate-sized earthquakes, among many cases that did not show any such changes. Background noise caused by other environmental variables and possible mechanisms for the pre-earthquake anomalies are discussed. Due to the complexity of earthquake prediction, much more monitoring efforts as well as sophisticated analytic and synthetic efforts are needed in the future.

The mean square exponential consensus problem for stochastic multi-agent systems with unbounded distributed delays is investigated. Two delayed impulsive pinning control protocols are proposed that are different from those of existing delay-free impulsive pinning controllers. By employing the Lyapunov function method, sufficient conditions are constructed under the presented strategies. It is shown that the system can realize mean square exponential consensus by controlling a small portion of agents. Then, the simulations indicate that the scheme is both feasible and effective.

This paper investigates finite-time synchronization problem for a class of Markovian jumping stochastic complex dynamical systems with mixed time delays. Hybrid controllers including nonlinear controller and impulsive controller are designed for the model to be finite-time synchronization. Based on stochastic analysis technique, Lyapunov function method and the inequality technique, some sufficient criterion for the stochastic complex dynamical networks are presented to guarantee finite-time synchronization. It is shown that the finite-time synchronization can be effectively realized by the designed hybrid controllers. Finally, numerical examples are provided to illustrate the theoretical results, which demonstrate that our results are effectiveness for the stochastic complex systems.

This paper investigates the mean square consensus problem of dynamical networks of leader-following multi-agent systems with measurement noises and time-varying delays. We consider that the fixed undirected communication topologies are connected. A neighbor-based tracking algorithm together with distributed estimators are presented. Using tools of algebraic graph theory and the Gronwall-Bellman-Halanay type inequality, we establish sufficient conditions to reach consensus in mean square sense via the proposed consensus protocols. Finally, a numerical simulation is provided to demonstrate the effectiveness of the obtained theoretical result.

Exponential consensus of non-linear stochastic multi-agent systems is investigated. The authors consider a class of non-linear stochastic multi-agent systems that are subject to time-varying delays, randomly occurring uncertainties and randomly occurring non-linearities. Impulsive pinning control algorithms are proposed to ensure that follower agents track the leader under a fixed topology. On the basis of the Lyapunov function and the Halanay differential inequality of impulsive dynamical systems, we derive sufficient conditions for the globally exponential consensus of the multi-agent systems. Finally, numerical simulations demonstrate the effectiveness of the proposed theoretical results.

The distributed constant-batch random projection subgradient algorithm is put forward to solve a constrained non-differentiable convex optimization problem. The constraint set can be written as intersections of some closed convex subsets and each subset is also composed of intersections. The multi-agent network under switching communication graph with fixed time delays is discussed. Each agent only knows its own cost function and is restricted to its own constraint set. A system expansion way is proposed in this paper to convert the network with fixed delays to the network without delays. At each iteration, we randomly select the components of the constant-batch restricted set for each agent and sequentially project the current state of the agent onto the selected sets by using subgradient information. Under the general assumption, the proposed algorithm can make all agents converge to the same optimal point. Finally, we give a numerical simulation example to verify the proposed algorithm.

Cu/Zn superoxide dismutase (SOD) and catalase (CAT) cDNAs from the polychaete Perinereis aibuhitensis were cloned and characterized in order to investigate the relationship between crude oil exposure and stress response in this worm. The full length of PaSOD was 870 bp and PaCAT was 1967 bp encoding 150 and 506 amino acids, respectively. Gene expression and enzyme activity of Cu/Zn SOD and CAT in response to crude oil contaminated soil (500, 1500, and 3000 mg/kg) were measured. The results showed that expression of the CAT gene and enzyme activity in P. aibuhitensis was positively correlated to the concentration of crude oil and reached a maximum at 15 days of exposure to 3000 mg/kg crude oil. The expression of the SOD gene and enzyme activity of SOD in P. aibuhitensis also increased during exposure to crude oil and reached a maximum at 10 days of exposure to 3000 mg/kg crude oil. These results indicated that SOD and CAT are important for maintaining the balance of cellular metabolism and protecting P. aibuhitensis from crude oil toxicity.

A series of choline chloride-based deep eutectic solvents (ChCl-DESs) were synthesized and characterized, and their performance in the dissolution of cellulose was investigated. The hydrogen-bond donors significantly (β-value) affected the properties of ChCl-DESs, causing differentiated dissolution performances. ChCl- imidazole (Im) showed the highest Hammett acidity function (1.869), hydrogen bond basicity (0.864), and dipolarity/polarizability effect (0.382) among the ChCl-DESs. The ChCl-Im showed the lowest pseudo-activation energy for viscous flow (31.76 kJ mol-1) among the ChCl-DESs. The properties of ChCl-Im caused the highest solubility of cellulose (2.48 wt.%) relative to the other ChCl-DESs. Polyethylene glycol (PEG), as a co-solvent, significantly (β-value) enhanced the accessibility of ChCl-Im to cellulose by breaking the supramolecular structure of cellulose, promoting its dissolution. The decrystallization of ChCl-Im-coupled PEG approximately doubled the dissolving capabilities, and the solubility increased by more than 80% in comparison with only ChCl-Im. The cellulose was directly dissolved by ChCl-Im-coupled PEG, and no other derivatives were produced.

Frequency control is essential to maintain the supply stability and security in microgrid. In islanded mode, energy storage systems (ESS) or load control was often used to solve frequency fluctuations. However, the use of energy storage systems will be followed by a huge investment. Besides, the load control scheme don’t distinguish importance of load, the load of importance will be greatly impact. In this paper, an adaptive flexible power electronic loads (FPELs) control method considering the importance of load is proposed, which solves the problem of imbalance between supply and demand. So that the frequency deviation of the microgrid is within the allowable range. In the proposed control scheme, the FPELs are divided into three grades according to importance degree. The control strategy enables load to be orderly involved in supply-demand regulation according to its importance. So, this method reduces the impact on important loads. Frequency as the control signal of load saves communication investment. As a result, the control strategy keeps balance between supply-demand of microgrid. Matlab simulation results show the effectiveness of the control strategy.

In this paper, the quantized H ∞ feedback control problem is investigated for a class of stochastic networked systems with quantization and probabilistic data missing. The parameter uncertainties are time-varying norm-bounded and appear in both the state and input matrices. Input-delay approach is employed to model the networked control systems where the state and control signal are quantized by two logarithmic quantizers, respectively. By assuming that the network packet loss rate and employing the probability distribution characteristic of packet dropouts, the considered stochastic networked system with stochastic input-delay is transformed into a system with stochastic parameter. Based on that, robust mean-square exponential stability of the system with an H ∞ performance is guaranteed and quantized H ∞ controller design procedure is proposed. Finally, a numerical simulation example is exploited to show the effectiveness of the results derived.

The dissolution of cellulose is an important pretreatment method required for some of its catalytic conversion processes. Morpholinium-based ionic liquids (ILs) are challenging solvent choices available for “greener” and “cheaper” dissolution of cellulose. In this study, morpholinium-based ILs were prepared, and their influencing factors were experimentally investigated. The unique bipolar chemical structure derived from oxygen (electron-rich center) and nitrogen (electron-poor center) considerably enhanced the Hammett acidity function (H0) of task-ILs. N-Methyl-N-allyl-morpholinium acetate IL showed the highest H0 (2.324) and polarizability power (1.096). The anion of ILs determined the hydrogen bond basicity (β). The acetate anion contributed to β (0.88) values. As to fluid properties, the morpholinium-based ILs exhibited much lower viscosity. The properties of ILs improved the dissolution efficiency. The cellulose was directly dissolved in morpholinium-based Ils, and no other derivatives were formed. The cations and the anions of ILs studied reacted with oxygen and hydrogen atoms on the hydroxyl groups of cellulose, respectively.