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Iron nitrides with the merits of high theoretical capacities, cost-effectiveness, and good electronic/ionic conductivity have been recognized as attractive anode candidates for lithium-ion batteries (LIBs). Carbon compositing, pore engineering, and nanostructure construction have proved to be effective strategies to prepare high-performance metal nitride anodes for LIBs. Herein, we synthesized a series of Fe3N-embedded and N-doped carbon nanorods (Fe3N@NCNR) with a hierarchical porous system and controllable topography by metal-catalyzed graphitization-nitridization of the Fe(III)-triazole framework (Fe-MOF) and thermal evaporation of the triblock copolymer F127 template assembled in Fe-MOF via hydrogen bonding interaction, followed by the air oxidation and urea-assisted ammonolysis processes. The Fe3N@NCNR as anodes for LIBs display extraordinary lithium storage capabilities with a high reversible capacity of 830 mA h g–1at 0.1 C, a good rate performance of 576 mAh g–1at 5 C, and a long-term cycling stability of 742 mA h g–1over 600 cycles at 1 C. Such outstanding performance benefits from the spongy carbon nanorods with rich macropores for rapid electronic/ionic transport and effective accommodation of electrode volume expansion, abundant N-doped meso-/microporous carbon for the additional storage of Li+via capacitive effect, and the efficient utilization of Fe3N nanoparticles uniformly distributed through carbon nanorods. Importantly, this work introduces an effective strategy to construct superior performance nitride anodes from MOF surfactants based on hydrogen bonding-driven interface self-assembly and provides insight into the preparation of highly efficient nanoarchitectures for Li+storage.

Transition metal oxides with the merits of high theoretical capacities, natural abundance, low cost, and environmental benignity have been regarded as a promising anodic material for lithium ion batteries (LIBs). However, the severe volume expansion upon cycling and poor conductivity limit their cycling stability and rate capability. To address this issue, NiO embedded and N-doped porous carbon nanorods (NiO@NCNR) and nanotubes (NiO@NCNT) are synthesized by the metal-catalyzed graphitization and nitridization of monocrystalline Ni(II)-triazole coordinated framework and Ni(II)/melamine mixture, respectively, and the following oxidation in air. When applied as an anodic material for LIBs, the NiO@NCNR and NiO@NCNT hybrids exhibit a decent capacity of 895/832 mA h g–1at 100 mA g–1, high rate capability of 484/467 mA h g–1at 5.0 A g–1, and good long-term cycling stability of 663/634 mA h g–1at 600th cycle at 1 A g–1, which are much better than those of NiO@carbon black (CB) control sample (701, 214, and 223 mA h g–1). The remarkable electrochemical properties benefit from the advanced nanoarchitecture of NiO@NCNR and NiO@NCNT, which offers a length-controlled one-dimensional porous carbon nanoarchitecture for effective e–/Li+transport, affords a flexible carbon skeleton for spatial confinement, and forms abundant nanocavities for stress buffering and structure reinforcement during discharge/charging processes. The rational structural design and synthesis may pave a way for exploring advanced metal oxide based anodic materials for next-generation LIBs.

Optimizing multistage processes, such as distillation or absorption, is a complex mixed-integer nonlinear programming (MINLP) problem. Relaxing integer into continuous variables and solving the easier nonlinear programming (NLP) problem is an optimization idea for the multistage process. In this article, we propose a relaxation method based on the efficiency parameter. When the efficiency parameter is 1 or 0, the proposed model is equivalent to the complete existence or inexistence of the equilibrium stage. And non-integer efficiency represents partial existence. A multi-component absorption case shows a natural penalty for non-integer efficiency, which can assist the efficiency parameter converging to 0 or 1. However, its penalty is weaker than the existing relaxation models, such as the bypass efficiency model. In a simple distillation case, we show that this property can weaken the nonconvexity of the optimization problem and increase the probability of obtaining better optimization results.

As a typical nonlinear system, the prediction of state variables and system control in distillation column systems face numerous challenges. The dynamic mode decomposition (DMD) method can construct an approximate linearized model of the system based on the state and input variables of the nonlinear system. In this paper, the DMD method is used to obtain an approximate linearized model of the distillation column system, which can predict the system’s state variables. This model is then utilized as the prediction model for designing a model predictive controller in model predictive control (MPC). The aim is to achieve the prediction of the state variables of simple and complex distillation systems and control the system effectively. By comparing the approximate linearized model obtained using the DMD method with the local linearized model obtained by linear expansion at the steady-state point, it is found that the approximate linearized model is more accurate for system reconstruction and prediction of the future outputs of the system. The feasibility and effectiveness of the DMD-MPC algorithm are investigated using a binary column system and four product Kaibel dividing-wall distillation column systems as case studies. It is found that the MPC designed using this approximate linearized model as the prediction model has good dynamic performance with small maximum and steady-state deviations and can suppress disturbances well.

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ABSTRACTThe aim of this study was to evaluate seroepidemiology of varicella in Wuxi, China, after two doses of immunization of varicella vaccine (VarV) for better control of varicella transmission. Participants were selected randomly by multistage stratified sampling. The positive rate of antibody and geometric antibody titer (GMC) was determined with enzyme-linked immunosorbent assays. Logistic and linear regressions were used to analyze the correlations between antibody seropositivity, GMCs, and corresponding factors. Serum samples (n = 697) were obtained from healthy children <7 years-of-age. Seropositivity and GMC were 67.84% and 190.97 mIU/mL, respectively, in subjects receiving two doses of VarV. Multivariate analysis revealed that both the rate of varicella-zoster virus immunoglobulin G seropositivity and GMC in vaccinated subjects were higher compared to those who had not been vaccinated. The strongest overall response was observed in subjects with two doses of VarV (4.055, 95% CI: 2.774 ~ 5.928). In 470 subjects with a history of VarV application, the antibody GMC value was reduced 4 years after vaccination. Two-dose vaccination with VarV was an effective prevention strategy varicella and should be included in a national immunization program.

The thermal safety of lithium-ion batteries has garnered significant attention due to its pivotal role in the field of new energy. In this work, a three-dimensional electrochemical-thermal coupling model based on the P2D model was established for predicting the thermal performance. The charge-discharge and temperature rise experiments via 18650 cylindrical Li[Ni0.6Co0.2Mn0.2]O2/ graphite batteries are designed to confirm the rationality of the model. The simulation results show that the highest temperature of the battery surface during discharging at 1 C and 4 C are 42.85 °C and 61.25 °C, and the experimental results are 42.50 °C and 62.85 °C, respectively. The electrode heat generation mainly comes from the reaction heat of cathode and anode during 1 C charge process, the maximum power is 1.2 W and 0.6 W, respectively. In the discharge process, the cathode dominates the reaction contribution of 1.02 W and the reaction heat power from the anode is only 0.016 W. The capacity of heat dissipation can be increased by enhancing the convective heat transfer coefficient and air velocity within a reasonable range. The proposed electrochemical-thermal coupling model is valuable to evaluate the heat behavior and promote the battery development.

Dipeptidyl peptidase-IV (DPP-IV) plays a critical role in glucose metabolism and has become an important target for type 2 diabetes mellitus. We previously reported a two-photon fluorescent probe glycyl-prolyl-N-butyl-4-amino-1,8-naphthalimide (GP-BAN) for DPP-IV detection with high specificity and sensitivity. In this study, a high-throughput screening (HTS) method for DPP-IV inhibitors using human plasma as the enzyme source was established and optimized. Further investigations demonstrate that the IC50value of sitagliptin (listed as the DPP-IV inhibitor) determined with human recombinant DPP-IV (36.22 nM) is very similar to that in human plasma (39.18 nM), and sitagliptin acts as a competitive inhibitor against human plasma DPP-IV-mediated GP-BAN hydrolysis. These results indicate that expensive human recombinant DPP-IV can be replaced by human plasma in this GP-BAN-based assay. On this basis, GP-AMC (commercial probe) was used as a comparison to verify this method, and the catalytic efficacy (Vmax/Km) for GP-AMC (0.09 min−1) hydrolysis in human plasma is lower than that for GP-BAN (0.21 min−1). Further analysis of inhibition kinetics (sitagliptin) and molecular docking (GP-BAN and GP-AMC) showed that GP-BAN has better specificity and affinity for enzymes than GP-AMC. Finally, the optimized method was used for the HTS of DPP-IV inhibitors in 69 natural alkaloids.

The potential of adopting asymmetrical temperature control (ATC) schemes to tightly control dividing-wall distillation columns (DWDCs) has yet to be fully explored due to the following two problems. First, the inference accuracy toward the controlled product purity of the candidate controlled variables (CCVs) synthesized for each control loop was not high enough. Second, the determination of the most appropriate CCV for each control loop lacked a sufficient theory basis. To alleviate these two problems, two measures are specially adopted in the current work, thereby forming a systematic method for deriving the ATC schemes. First, the creations of a double temperature difference (DTD) and temperature difference (TD) are reformed with the aid of a recently defined performance metric, the averaged absolute variation magnitudes (AAVMs). Namely, DTD is generated according to a novel method based on the AAVMs, rather than the conventional method based on the sensitivity analysis and SVD analysis, and TD is modified in form through multiplying the temperature of the reference stage by a coefficient that equals the ratio of the AAVMs of the sensitive stage and the reference stage. Then, a sequential search procedure is proposed to help determine the most appropriate CCV for each control loop from all of the synthesized CCVs with a combined consideration of the inference accuracy to the controlled product purity and the interaction between control loops. In terms of the operation of a benzene–toluene–o-xylene DWDC, the proposed method is assessed by means of a thorough comparison between the derived ATC scheme and the double temperature difference control scheme. In comparison with the latter, the former displays not only relatively better transient responses but also smaller steady-state deviations in the three controlled product qualities. These findings demonstrate the effectiveness and feasibility of the method proposed for deriving ATC schemes.

Dipeptidyl peptidase-IV (DPP-IV), an important prolyl-specific peptidase in the serine hydrolase family, hydrolyzes a large number of endogenous oligopeptides. In clinical studies, the detection of DPP-IV, especially the detection of its activity, is particularly important. We previously reported a specific fluorescent two-photon probe for DPP-IV. In this study, to further verify that our probe can be used for DPP-IV activity detection, we developed an accurate and sensitive method for the determination of DPP-IV activity in human tissue microsomes, cell homogenates or cell supernatants by liquid chromatography-fluorescence detection (LC-FD). This method is based on the fluorescence generated from BAN obtained from the hydrolysis of GP-BAN by detecting DPP-IV. The linearity, sensitivity, recovery, precision and stability of the method were fully validated. The method based on LC-FD has a lower limit of quantitation for BAN (product of DPP-IV), as low as 5 nM (only needs 2 μL), which is much lower than that of the others. This method also demonstrated good accuracy and precision; variances of both were less than 15% between the intra- and inter-assay. In addition, the method was successfully applied to the determination of DPP-IV activity in various cell homogenates and cell supernatants. The development of the LC-FD method will help to understand the expression and function of DPP-IV in different biological samples in humans for future studies.

The separations of quaternary reversible reactions with the most unfavorable ranking of relative volatilities (i.e., the two reactants are the lightest and heaviest components and the two products in between) require a reactive distillation column, followed by one or two conventional distillation columns. The multiple-column structure reflects not only a high energy intensity in the reaction operation and separation operation involved but also a great potential of process intensification in process development. With reference to a two-column system involving a reactive distillation column with an external recycle and a conventional distillation column (ER-RDC + CDC), a kind of reactive double dividing-wall distillation column (R-DDWDC) is derived via careful coordination and mass and thermal coupling between the ER-RDC and CDC. Closely dependent upon the magnitude of the reaction thermal effect, the left dividing wall is located either at the top or at the bottom. In addition to allowing the mass and thermal coupling between the ER-RDC and CDC, it facilitates primarily the reaction operation in the reactive section. The right dividing wall is located at the middle to fully strengthen the mass and thermal coupling not only between the ER-RDC and CDC but also between the separation operations included. The derived R-DDWDC features essentially the greatest degree of process intensification and becomes consequently the most thermodynamically efficient scheme in the separations of quaternary reversible reactions with the most unfavorable ranking of relative volatilities. The derived R-DDWDC is evaluated in terms of two examples, involving, respectively, the separations of ideal exothermic and endothermic quaternary reversible reactions with the most unfavorable ranking of relative volatilities. The derived R-DDWDC is found to be much more energy efficient than the ER-RDC + CDC, the reactive single dividing-wall distillation column, and those R-DDWDCs with different configurations. These outcomes demonstrate that the derived R-DDWDC is a much competitive alternative for the separations of quaternary reversible reactions with the most unfavorable ranking of relative volatilities. They also highlight the feasibility and effectiveness of the proposed strategy for process synthesis and design, that is, when the reaction processed is exothermic, the optimum R-DDWDC must come from one of R-DDWDC2 and R-DDWDC4; otherwise, the R-DDWDC4 remains to be the only possibility.

Complex nanostructures with distinct spatial architectures and more active sites hold broad prospects in new energy conversion fields. Herein, a facile strategy was carried out to construct triple-shelled Co-VSexnanocages, starting with an ion-exchange process between Co-based zeolitic imidazolate framework-67 (ZIF-67) nanopolyhedrons and VO3–followed by the formation of triple-shelled Co-VSexhollow nanocages during the process of increasing the solvothermal temperature under the assistance of SeO32–. Meanwhile, triple-shelled Co-VSxand yolk–double shell Co-VOxnanocages were fabricated as references by a similar process. Benefiting from the larger surface areas and more electrolyte adsorption sites, the triple-shelled Co-VSexnanocages exhibited excellent electrocatalytic performances when applied as the electrochemical catalysts for dye-sensitized solar cells (DSSC) and hydrogen evolution reactions (HER). More concretely, the DSSC based on the Co-VSexcounter electrode showed outstanding power conversion efficiency of 9.68% when its Pt counterpart was 8.46%. Moreover, the Co-VSexelectrocatalyst exhibited prominent HER performance with a low onset overpotential of 40 mV and a small Tafel slope of 39.1 mV dec–1in an acidic solution.

A highly efficient and stable electrocatalyst with the novel heterostructure of Co-embedded and N-doped carbon nanotubes supported Mo2C nanoparticles (Mo2C/NCNTs@Co) is creatively constructed by adopting the one-step metal catalyzed carbonization–nitridation strategy. Systematic characterizations and density functional theory (DFT) calculations reveal the advanced structural and electronic properties of Mo2C/NCNTs@Co heterostructure, in which the Co-embedded and N-doped CNTs with tunable diameters present electron-donating effect and the work function is correspondingly regulated from 4.91 to 4.52 eV, and the size-controlled Mo2C nanoparticles exhibit Pt-like 4d electronic structure and the well matched work function (4.85 eV) with I–/I3–redox couples (4.90 eV). As a result, the conductive NCNTs@Co substrate with fine-tuned energy level alignment accelerates the electron transportation and the electron migration from NCNTs@Co to Mo2C, and the active Mo2C shows high affinity for I3–adsorption and high charge transfer ability for I3–reduction, which reach a decent synergetic catalytic effect in Mo2C/NCNTs@Co heterostructure. The DSSC with Mo2C/NCNTs@Co CE achieves a high photoelectric conversion efficiency of 8.82% and exceptional electrochemical stability with a residual efficiency of 7.95% after continuous illumination of 200 h, better than Pt-based cell. Moreover, the synergistic catalytic mechanism toward I3–reduction is comprehensively studied on the basis of structure–activity correlation and DFT calculations. The advanced heterostructure engineering and electronic modulation provide a new design principle to develop the efficient, stable, and economic hybrid catalysts in relevant electrocatalytic fields.

Methyl linolenate was separated from its analogues by a new extraction system constructed by solvent, imidazolium based ionic liquids and cuprous salt. Firstly, the effect of ionic liquid on the dissolution of CuCl in acetonitrile, N,N-dimethylformamide (DMF), methanol and water was evaluated by visual observation. [C4Mim][Cl] can improve the dissolution of CuCl in acetonitrile. Then, for the new system as acetonitrile-ILs-CuCl, extraction equilibrium, distribution ratio and selectivity of methyl linolenate and its analogues were determined by gas chromatography analysis and the mass balance. The extraction time, IL structures and CuCl concentrations were investigated. Distribution ratio decreased slightly, but selectivity increased significantly with the addition of CuCl, [C4Mim][Cl] or [C4Vim][NTF2] into acetonitrile. [C4Vim][NTF2] had higher selectivity than [C4Mim][Cl]. But the selectivity of the system combining CuCl with [C4Vim][NTF2] was much lower than with [C4Mim][Cl]. For the CuCl-[C4Mim][Cl]-acetonitrile, the extraction efficiency was better than CuCl-acetonitrile, increasing Cu+concentration effectively improved the separation selectivity when ratio of CuCl/[C4Mim][Cl] was less than 1. Compared with previous aqueous AgNO3extractions, the method of using CuCl is a much cheaper and practical way to enrich unsaturated fatty acid.

Temperature inferential control (TIC) is studied for a reactive distillation column with double reactive sections (RDC-DRSs) processing a hypothetical two-stage consecutive reversible reaction (A + B ↔ C + D, C + B ↔ E + D with αD > αB > αC > αA > αE). Because of the complicated dynamic behaviors, the controlled stages by sensitivity analysis lead to great steady-state deviations (SSDs) in top and bottom product purities. Since TIC involves considerably reduced settling times in comparison with direct composition control, small SSDs in product qualities correspond generally to small transient deviations (TDs) in product qualities. An objective function that measures SSDs in product qualities is formulated to represent the performance of a TIC system and an iterative procedure is devised to search for the best control configuration. The application of the procedure to the RDC-DRS gives considerably suppressed TDs and SSDs in top and bottom product qualities as compared with the one by sensitivity analysis. The method is simpler in principle and less computationally intensive than the current practice. These striking outcomes show the effectiveness of the proposed principle for the development of TIC systems for complicated reactive distillation columns.

The internal seismic architectures of the Middle Miocene in Beikang Basin, southern South China Sea, were investigated and described using regional 2D seismic data from Guangzhou Marine Geology Survey. In particular, five typical seismic facies were identified based on an integrated analysis of the amplitude, continuity, contact relationship, and morphologies of seismic reflections. Bathyal-abyssal fine-grained sediments, deltaic front sandy bodies, turbidites, and small-scale turbidite channels were developed in the Middle Miocene according to the tectonic-sedimentary evolution of the sedimentary basins in the southern South China Sea. The findings of this study suggest that deltaic front sandy bodies and turbidites can be considered as the two major types of deep-water clastic reservoirs for the depression stage of Beikang Basin. A well-developed source-reservoir-cap assemblage was composed by deep rift-stage source rocks, deep-water clastic reservoirs of the Middle Miocene, and bathyal-abyssal deep-water fine-grained sediments after the Middle Miocene, implying a good potential for hydrocarbon exploration.

Due to the topological structure of double columns and multiple separating sections in dividing-wall distillation columns (DWDCs), the development of vapor recompressed dividing-wall distillation columns (DWDC-VRHPs) represents a challenging issue with great complexities and tediousness. For the separations of light-component dominated and wide boiling-point ternary mixtures, because the purification of the light-component from the intermediate- and heavy-components incurs the primary energy dissipation, the application of vapor recompressed heat pumps (VRHP) should be aimed to reduce the irreversibility and this leads to the generation of the optimum topological structures of the DWDC-VRHPs, i.e., a DWDC plus a two-stage VRHP. The first-stage VRHP is to preheat feed, not only taking the advantages of the small temperature elevation available but also favoring the mass transfer between the vapor and liquid phases through feed splitting. The second-stage VRHP is to reduce further separation irreversibility. The philosophy can be applied to any DWDCs no matter where the dividing wall locates. Two case studies on the separations of ternary mixtures of benzene, toluene, and o-xylene and n-pentane, n-hexane, and n-heptane demonstrate the economic optimality of the proposed DWDC-VRHPs and reveal the inherent interplay between internal and external process integration.

In our recent work, the arrangement of multiple reactive sections is found to greatly enhance the steady-state performance of reactive distillation columns disproportionating trichlorosilane to silane. In the current research, process dynamics and controllability are studied through in-depth comparative analysis of open-loop and closed-loop behaviors between three reactive distillation columns with, respectively, a single reactive section (RDC-SRS), double reactive sections (RDC-DRS), and triple reactive sections (RDC-TRS). In the regulation path, although the arrangement of double and triple reactive sections reduces slightly the process gains between the bottom product composition and reboiler heat duty in the RDC-DRS and RDC-TRS, it helps to alleviate the coupling between the bottom product composition and reflux flow rate, thereby gaining increases in process controllability as compared with the RDC-SRS. In the disturbance path, the arrangement of double and triple reactive sections results in no intensified sensitivities to the disturbances from feed flow rate and composition. The closed-loop operation tests coincide with the open-loop analysis and demonstrate that the RDC-TRS and RDC-DRS exhibit substantially improved antidisturbance and set-point tracking capabilities as compared with the RDC-SRS. These outcomes highlight evidently the great importance of arranging multiple reactive sections to the dynamics and controllability of reactive distillation columns separating reacting mixtures with unfavorable and complicated reaction kinetics.

Ultrawide-spectra-compatible camouflage materials are imperative for military science and national security due to the continuous advancement of various sophisticated multispectral detectors. However, ultrawide spectra camouflage still has challenges, as the spectral requirements for different bands are disparate and even conflicting. This work demonstrates an ultrawide spectra camouflage material compatible with visible (VIS, 400–800 nm), infrared (IR, 3–5 and 8–14 μm), and microwave (S–Ku bands, 2–12 GHz). The carbon nanotubes adsorbed on porous anodic alumina/aluminum flake powder (CNTs@PAA/AFP) material for ultrawide spectra camouflage is composed of bioinspired porous alumina surface layers for low visible reflection and aluminum flake powder substrate for low infrared emissivity, while the surface of the porous alumina layers is loaded with carbon nanotubes for microwave absorption. Compared with previous low-emissivity materials, CNTs@PAA/AFP has omnidirectional low reflectance (Ravg= 0.29) and high gray scale (72%) in the visible band. Further, it exhibits low emissivity (ε3–5μm= 0.15 and ε8–14μm= 0.18) in the dual infrared atmospheric window, which reduces the infrared lock-on range by 59.6%/49.8% in the mid/far-infrared band at high temperatures (573 K). The infrared camouflage performance calculated from the radiation temperature of CNTs@PAA/AFP coatings is enhanced to over 65%, which is at least 4 times greater than that of its substrate. In addition, the CNTs@PAA/AFP coating achieves high microwave absorption (RLmin= −42.46 dB) and an effective absorption bandwidth (EAB = 7.43 GHz) in the microwave band (S–Ku bands) due to the enhancement of interfacial polarization and conductive losses. This study may introduce new insight and feasible methods for multispectral manipulation, electromagnetic signal processing, and thermal management via bioinspired structural design and fabrication.

Patients with major depressive disorder (MDD) can present with altered brain structure and deficits in cognitive function similar to aging. Yet, the interaction between age-related brain changes and brain development in MDD remains understudied. In a cohort of adolescents and adults with and without MDD, we assessed brain aging differences and associations through a newly developed tool quantifying normative neurodevelopmental trajectories.

Although dividing wall technology is very effective for process intensification of distillation, the resultant dividing-wall distillation columns (DWDCs) exhibit strongly interactive and highly nonlinear behaviors, which may pose great challenges to process operations. Proportional–integral (PI) controllers can stabilize the operation of the DWDC, but their performances are frequently far from satisfactory. Model predictive control (MPC) can potentially improve performance sharply, but the stringent requirements on the qualities of the embedded model considerably lower its robustness. To suppress these two deficiencies, in this work a cascaded control structure by combining the MPC and PI controllers is proposed for the DWDC. The PI controllers regulate the stage temperature in the inner layer, serving to quickly stabilize the DWDC, while the MPC directly controls the product compositions in the outer layer, addressing the strongly interactive and highly nonlinear behaviors of the DWDC. Two typical cases, that is, a three-product Petlyuk DWDC and a four-product Kaibel DWDC, and five control schemes, that is, two impurity composition controls (PI-ICC and MPC-ICC), two purity composition controls (PI-PCC and MPC-PCC), and one pure temperature control PI-TC (which represents the case wherein MPC in the outer layer fails to work), are studied to evaluate the feasibility and effectiveness of the proposed control structure. It is found that the cascaded MPC/PI controllers (i.e., MPC-ICC and MPC-PCC) substantially outperform the pure PI controllers (i.e., PI-ICC and PI-PCC), with lower maximum and steady-state deviations, shortened settling times, and suppressed oscillations. In the case of failure of the MPC, the cascaded MPC/PI controller can still maintain stable operation of the DWDC. These outcomes highlight that the combination of MPC and PI controllers can be a potential method for the operation of highly interactive and complicated DWDCs.

A new class of hybrids with the unique electrocatalytic nanoarchitecture of Fe1–xS anchored on Fe3C-encapsulated and N-doped carbon nanotubes (Fe1–xS/Fe3C–NCNTs) is innovatively synthesized through a facile one-step carbonization–sulfurization strategy. The efficient synthetic protocols on phase structure evolution and dynamic decomposition behavior enable the production of the Fe1–xS/Fe3C–NCNT hybrid with advanced structural and electronic properties, in which the Fe vacancy-contained Fe1–xS showed the 3d metallic state electrons and an electroactive Fe in +2/+3 valence, and the electronic structure of the CNT was effectively modulated by the incorporated Fe3C and N, with the work function decreased from 4.85 to 4.63 eV. The meticulous structural, electronic, and compositional control unveils the unusual synergetic catalytic properties for the Fe1–xS/Fe3C–NCNT hybrid when developed as counter electrodes (CEs) for dye-sensitized solar cells (DSSCs), in which the Fe3C- and N-incorporated CNTs with reduced work function and increased charge density provide a highway for electron transport and facilitate the electron migration from Fe3C–NCNTs to ultrahigh active Fe1–xS with the electron-donating effect, and the Fe vacancy-enriched Fe1–xS nanoparticles exhibit ultrahigh I3–adsorption and charge-transfer ability. As a consequence, the DSSC based on the Fe1–xS/Fe3C–NCNT CE delivers a high power conversion efficiency of 8.67% and good long-term stability with a remnant efficiency of 8.00% after 168 h of illumination, superior to those of traditional Pt. Furthermore, the possible catalytic mechanism toward I3–reduction is creatively proposed based on the structure–activity correlation. In this work, the structure engineering, electronic modulation, and composition control opens up new possibilities in constructing the novel electrocatalytic nanoarchitecture for highly efficient CEs in DSSCs.

The focus of this paper is to investigate different control structures (single-loop PI control) for a dividing wall (Petlyuk) column for separating ethanol, n-propanol and n-butanol. Four control structures are studied. All the results are simulations based on Aspen Plus. Control structure 1 (CS1) is stabilizing control structure with only temperature controllers. CS2, CS3 and CS4, containing also composition controllers, are introduced to reduce the steady state composition deviations. CS2 adds a distillate composition controller (CCDB) on top of CS1. CS3 is much more complicated with three temperature-composition cascade controllers and in addition a selector to the reboiler duty to control the maximum controller output of light impurity composition control in side stream and bottom impurity control in the prefractionator. CS4 adds another high selector to control the light impurity in the sidestream. Surprisingly, when considering the dynamic and even steady state performance of the proposed control structures, CS1 proves to be the best control structure to handle feed disturbances inserted into the three-product Petlyuk column.

Transition metal chalcogenides with hollow nanostructures have been considered as promising substitutes as precious metal electrocatalysts for energy conversion and storage. We synthesized NiCo2S4double-shelled ball-in-ball hollow spheres (BHSs) via a simple solvothermal route and applied them in both dye-sensitized solar cells (DSSCs) and hydrogen evolution reactions (HERs) at the same time, which were clean and sustainable ways to convert energy. Benefiting from their remarkable structure features and advantageous chemical compositions, NiCo2S4BHSs composed of tiny crystals possessed large surface area, well-defined interior voids, and high catalytic activity. The DSSC with NiCo2S4BHSs under 100 mW cm–2irradiation possessed a power conversion efficiency of 9.49% (Pt, 8.30%). Besides, NiCo2S4BHSs as a HER catalyst also possessed a small onset overpotential (27.9 mV) and a low overpotential (89.7 mV at 10 mA cm–2) under alkaline conditions. Therefore, this work offers a sensible strategy to synthesize bifunctional electrocatalysts for DSSCs and HERs.

The development of highly active and stable earth-abundant electrocatalysts to reduce or eliminate the reliance on noble-metal based ones for hydrogen evolution reaction (HER) over a broad pH range remains a great challenge. Herein, hierarchical porous Co9S8/N-doped carbon@MoS2(Co9S8/NC@MoS2) polyhedrons have been synthesized by a facile hydrothermal approach using highly conductive Co/NC polyhedrons composed of cobalt nanoparticles embedded in N-doped carbon matrices as both the structural support and cobalt source. The Co/NC polyhedrons were prepared by direct carbonization of Co-based zeolitic imidazolate framework (ZIF-67) in Ar atmosphere. Benefiting from the prominent synergistic effect of N-doped carbon enhancing the conductivity of the hybrid, MoS2and Co9S8providing abundant catalytically active sites as well as the well-defined polyhedral structure promoting mechanical stability, the as-synthesized Co9S8/NC@MoS2shows excellent HER activity and good stability over a broad pH range, with onset overpotentials of 4, 38, and 45 mV, Tafel slopes of 60.3, 68.8, and 126.1 mV dec–1, and overpotentials of 67, 117, and 261 mV at 10 mA cm–2in 1.0 M KOH, 0.5 M H2SO4, and 1.0 M phosphate buffer solution (PBS), respectively. This work provides a general and promising approach for the design and synthesis of inexpensive and efficient pH-universal HER electrocatalysts.

Immobilization of weight bearing skeletons or microgravity results in disuse osteoporosis in both human and animals. Our previous study demonstrated that electrical stimulation at the dorsal root ganglion (DRG) with an implantable micro‐electrical stimulation system (IMESS) could trigger secretion of bone anabolic calcitonin gene‐related peptide (CGRP) and prevent bone loss in a short‐term hindlimb unloading rat model. This study was designed to further investigate whether electrical stimulation to the DRG could prevent bone loss due to prolonged unloading. Eighteen adult rats were randomly assigned into three groups: cage control (CC), hindlimb unloading (HU), and hindlimb unloading with electrical stimulation (HUES). Electrical stimulation was applied via IMESS to the right DRGs at vertebral levels L4–L6 in HUES group for 6 weeks. Following unloading for 6 weeks, proximal tibia metaphysis was shown 64.0% decrease in bone mineral content (BMC) and 47.0% decrease in bone mineral density (BMD) in HU group while significant reduced bone lose with 2.7% increase in total BMC and only 9.2% decrease in total BMD in HUES group. Diaphyseal BMD decreased significantly in both HU and HUES group as compared with CC group. There was enhancement of CGRP expression in the DRGs in HUES group. This experimental study proved the proposed concept using electrical stimulation at the DRG for prevention of disuse‐induced bone loss in a rat hindlimb suspension model.

In this work, morphology-tuned ternary nickel cobalt selenides based on different Ni/Co molar ratios have been synthesized via a simple precursor conversion method and used as counter electrode (CE) materials for dye-sensitized solar cells (DSSCs). The experimental facts and mechanism analysis clarified the possible growth process of product. It can be found that the electrochemical performance and structures of ternary nickel cobalt selenides can be optimized by tuning the Ni/Co molar ratio. Benefiting from the unique morphology and tunable composition, among the as-prepared metal selenides, the electrochemical measurements showed that the ternary nickel cobalt selenides exhibited a more superior electrocatalytic activity in comparison with binary Ni and Co selenides. In particular, the three-dimensional dandelion-like Ni0.33Co0.67Se microspheres delivered much higher power conversion efficiency (9.01%) than that of Pt catalyst (8.30%) under AM 1.5G irradiation.

In our previous work, the reactive dividing wall column (RDWC) was proposed and proved to be effective for selective hydrogenation and separation of C3 stream. In the present paper, the dynamics and control of the proposed RDWC are investigated. Four control structures including composition and temperature controls are proposed. The feed forward controllers are employed in the four control strategies to shorten the dynamic response time, reduce the maximum deviations and offer an immediate adjustment. The control structures are compared by applying them into the RDWC system with 20% disturbances in both the feed flow rate and the feed compositions, and the results are discussed.

The focus of this paper is to investigate stabilizing control (single-loop PID control) of a dividing wall column (DWC) for separating ethanol, n-propanol and n-butanol at atmospheric pressure. Three control structures are studied: control structure with fixed split ratios (CS1), control structure with an active liquid split (CS2) and control structure with an active vapor split ratio (CS3). The dynamic performances of the three proposed control structures prove that the three control structures are able to handle feed disturbances inserted into DWC. The simple control structure with fixed split ratios (CS1) is more applicable in industry. Considering the vapor split ratio disturbance, CS2 and CS3 are better than CS1. If the feed composition of A rarely changes, CS3 is able to handle the other feed disturbances. This paper proves that the three-product DWC can be controlled with only three temperature controllers.

This paper presents a method for identifying a patient’s wake/sleep state for closed-loop deep brain stimulation (DBS). The method uses a real-time wake/sleep identification algorithm that includes posture analysis based on the movement of the chest below the clavicle, which is the location of the subcutaneous pulse generator. A single micro-accelerometer was used to monitor the movement of the wrist and the chest of thirteen healthy adults and twelve patients with Parkinson’s disease for nine continuous hours. The wake/sleep state identification for the chest algorithm had accuracy, sensitivity, and specificity values of 85.78, 84.21, and 82.08 %, respectively, compared to video recordings for patients with DBS ON, and 82.74, 82.68, and 82.28 %, respectively, for patients with DBS OFF. The algorithm performance for the chest is comparable to that of the commonly used location on the wrist. The real-time wake/sleep identification algorithms were proved to be effective. This research provides a practical method for closed-loop DBS, which will greatly benefit patients with Parkinson’s disease.

A novel class of metal-free organic dyes based on benzo[a]carbazole have been designed, synthesized, and used in dye-sensitized solar cells for the first time. These types of dyes consisted of a cyanoacrylic acid moiety as the electron acceptor/anchoring group and different electron-rich spacers such as thiophene (JY21), furan (JY22), and oligothiophene (JY23) as the π-linkers. The photophysical, electrochemical, and photovoltaic properties, as well as theoretical calculations of these dyes were investigated. The photovoltaic performances of these dyes were found to be highly relevant to the π-conjugated linkers. In particular, dye JY23exhibited a broad IPCE response with a photocurrent signal up to about 740 nm covering the most region of the UV–visible light. A DSSC based on JY23showed the best photovoltaic performance with a Jscof 14.8 mA cm–2, a Vocof 744 mV, and a FF of 0.68, achieving a power conversion efficiency of 7.54% under standard AM 1.5 G irradiation.

Esculetin (6,7-dihydroxycoumarin) and its C-4 derivatives have multiple pharmacologic activities, but the poor metabolic stability of these catechols has severely restricted their application in the clinic. Glucuronidation plays important roles in catechols elimination, although thus far the effects of structural modifications on the metabolic selectivity and the catalytic efficacy of the human UDP-glucuronosyltransferase (UGT) enzymes remain unclear. This study was aimed at exploring the structure-glucuronidation relationship of esculetin and its C-4 derivatives, including 4-methyl esculetin, 4-phenyl esculetin, and 4-hydroxymethyl esculetin as well as 4-acetic acid esculetin. It was achieved by identifying the main human UGTs responsible for the different reactions and by careful characterization of the reactions kinetics. These catechols, with the exception of 4-acetic acid esculetin, are selectively metabolized to the corresponding 7-O-glucuronides. UGT1A6 and UGT1A9 are the two major UGTs involved in the 7-O-glucuronidation of 4-methyl esculetin and esculetin. UGT1A6 was the major contributor for 7-O-glucuronidation of 4-hydroxymethyl esculetin, and UGT1A9 played a significant role in the 7-O-glucuronidation of 4-phenyl esculetin. The results of the kinetic analyses revealed that the Kmvalues of the compounds, in both UGT1A9 and human liver microsomes, decreased with increasing hydrophobicity of the C-4 substitutions. The outcome of this was that C-4 hydrophobic and hydrophilic groups on 6,7-dihydroxycoumarin exhibited contrasting effects on UGT affinity. All of these findings provide helpful guidance for further structural modification of 6,7-dihydroxycoumarins with improved metabolic stability.

With the growth in demand for information processing, considering that cloud computing technology and virtual digital libraries have common goal. In this paper, take the cloud computing as the basis of virtual digital libraries, firstly, research the digital library virtualization under the circumstance of cloud computing; secondly, study digital books Museum of virtualized resources in a cloud computing environment integration and sharing mechanism; finally, creating digital library environment with cloud computing virtualization technology driven.

Esculetin (6,7-dihydroxycoumarin) and its C-4 derivatives have multiple pharmacologic activities, but the poor metabolic stability of these catechols has severely restricted their application in the clinic. Glucuronidation plays important roles in catechols elimination, although thus far the effects of structural modifications on the metabolic selectivity and the catalytic efficacy of the human UDP-glucuronosyltransferase (UGT) enzymes remain unclear. This study was aimed at exploring the structure-glucuronidation relationship of esculetin and its C-4 derivatives, including 4-methyl esculetin, 4-phenyl esculetin, and 4-hydroxymethyl esculetin as well as 4-acetic acid esculetin. It was achieved by identifying the main human UGTs responsible for the different reactions and by careful characterization of the reactions kinetics. These catechols, with the exception of 4-acetic acid esculetin, are selectively metabolized to the corresponding 7-O-glucuronides. UGT1A6 and UGT1A9 are the two major UGTs involved in the 7-O-glucuronidation of 4-methyl esculetin and esculetin. UGT1A6 was the major contributor for 7-O-glucuronidation of 4-hydroxymethyl esculetin, and UGT1A9 played a significant role in the 7-O-glucuronidation of 4-phenyl esculetin. The results of the kinetic analyses revealed that the Kmvalues of the compounds, in both UGT1A9 and human liver microsomes, decreased with increasing hydrophobicity of the C-4 substitutions. The outcome of this was that C-4 hydrophobic and hydrophilic groups on 6,7-dihydroxycoumarin exhibited contrasting effects on UGT affinity. All of these findings provide helpful guidance for further structural modification of 6,7-dihydroxycoumarins with improved metabolic stability.

With the increasing attention of textile, the wear resistance of the fabric is more and more important today. The wear resistance is judged by the sample and standard sample according to sensory contrast complete, but this approach has repeated poor consistency. The subjective factors of testers influence the result heavily. So the powerful image processing tools of MATLAB was used in the analysis of fabrics image processing. By image read, display and interception, image preprocessing, and feature extraction value, the eigenvalues of total area of the hair bulb, maximum area of the hair bulb, and hair bulb number were obtained. After the improved minimum distance discrimination method was used to determine the level of wear resistance by computer. Tests show that fabrics wear resistance level can be judged quickly, accurately and automatically.

Data warehouse is playing a more and more important role in company’s decision making; it is the basis for a typical business intelligence solution. The paper points out the reasons why data warehouse projects failed and by analyzing the current data warehouse architectures, as well as technologies used in industry, a new data warehouse architecture is proposed which has many advantages over current ones, for example, it is extensible, reusable, flexible and with high performance and lower cost.

This paper focuses mainly on a clustering method for pruning Fully Connected Backpropagation Neural Network (FCBP). The initial neural network is fully connected, after training with sample data, a clustering method is employed to cluster weights between input to hidden layer and from hidden to output layer, and connections that are relatively unnecessary are deleted, thus the initial network becomes a PCBP (Partially Connected Backpropagation) Neural Network. PCBP can be used in prediction or data mining more efficiently than FCBP. At the end of this paper, An experiment is conducted to illustrate the effects of PCBP using the submersible pump repair data set.

On the basis of the theory of market requirement, this paper reports research conducted on the basic elements that affect the satisfaction of medical institutions with their medical equipment maintenance. In addition, it helps to establish a requirement model of medical equipment maintenance through the research on the relation between the loss and medical treatment caused by the shutdown of the medical equipment because of its maintenance.

The mass and thermal coupling makes the control of the reactive double dividing-wall distillation column (R-DDWDC) an especially challenging issue with a highly interactive nature. With reference to the separation of an ideal endothermic quaternary reversible reaction with the most unfavorable ranking of relative volatilities (A + B ↔ C + D with αA > αC > αD > αB), the operation rationality of the R-DDWDC is studied in this contribution. The four-point single temperature control system leads to great steady-state discrepancies in the compositions of products C and D and the reason stems essentially from the failure in keeping strictly the stoichiometric ratio between reactants A and B. A temperature plus temperature cascade control scheme is then employed to reinforce the stoichiometric ratio control and helps to secure a substantial abatement in the steady-state discrepancies. A temperature difference plus temperature cascade control scheme is finally synthesized and leads even to better performance than the most effective double temperature difference control scheme. These outcomes reveal not only the operation feasibility of the R-DDWDC but also the general significance of the proposed temperature difference plus temperature cascade control scheme to the inferential control of any other complicated distillation columns.

The configuration of double columns and multiple separating sections for a dividing-wall distillation column (DWDC) makes the applications of vapor recompression heat pumps (VRHPs) a challenging task with great complexity and tediousness. Although many researchers revealed the great advantages of the VRHP-assisted dividing-wall distillation columns (VRHP-DWDCs), they have actually neglected such inherent issues in process development. In the current work, the optimum topological configuration of the VRHP-DWDC, i.e., a DWDC with a middle partition facilitated by two VRHPs, is derived for the separations of intermediate-component-dominated and wide-boiling-point ternary mixtures in terms of steady-state operating characteristics. Because of the maximized mass and thermal coupling between the prefractionator and main distillation column involved, excessive heat always exists around the location of the intermediate product. Via the two VRHPs, the excessive heat can effectively be used to aid the separation operation in the stripping section of the prefractionator or in the common stripping section. The first VRHP helps to reduce the operation irreversibility by taking the advantage of the small temperature elevation available between the location of the intermediate product and the common stripping section and releasing the excessive heat at an elevated temperature to the latter. The second VRHP serves to reduce further the operation irreversibility by compressing the overhead vapor stream preheated by the condensed liquid from the first VRHP and releasing its latent heat at an elevated temperature to the stripping section of the prefractionator or the common stripping section. Two case studies on the separations of intermediate-component dominated and wide-boiling-point ternary mixtures of benzene, toluene, and o-xylene and n-pentane, n-hexane, and n-heptane demonstrate the economic optimality of the proposed VRHP-DWDC. For the DWDC with a top or bottom partition, the optimum topological configuration of the VRHP-DWDC can also be derived in the same manner. The capability of predetermining the optimum topological configuration of the VRHP-DWDC can lower considerably the complicated and time-consuming work of process modeling, structural and operating parameter searching, and process screening in process development and is of great significance to the applications of this process intensification technology.

Though a Kaibel dividing-wall column (DWC) is able to save approximately 40% operation fees, the fear of controllability issues of the Kaibel DWC obstructs its large-scale industrialization. In our previous study, a composition/temperature cascade MPC-PI scheme was proposed with proportional–integral (PI) controllers stabilizing the operations and model predictive control (MPC) improving the performance. In the current paper, the MPC-PI scheme in combination with the data-driven soft sensor model replaces detecting compositions by detecting auxiliary variables, which is more applicable and practical. Although the same soft sensor model is applied, different Kalman filters used for error corrections will result in different composition estimation performances, which will consequently affect control performances for the Kaibel DWC. Soft sensors with different nonlinear Kalman filters have been studied and compared for the control scheme, containing the extended Kalman filter (EKF), unscented Kalman filter (UKF), and particle filter (PF). Research shows that the EKF can reach the setpoints of the product compositions faster than the UKF, but there are oscillations with reciprocating motion using the EKF. The speed of the PF to achieve stability is the fastest; however, the steady-state offsets remain. Therefore, the UKF is the most appropriate filter in composition soft sensors for the Kaibel DWCs, as its corresponding control performances are stable without the oscillations using the EKF and the steady-state offsets employing the PF.