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Bicyclohexane is a hydrogen storage reagent with high hydrogen density and low boiling point. Compared with the hydrogenation of biphenyl, the alkylation of benzene and cyclohexene to cyclohexylbenzene and hydrogenation is a promising way to prepare cyclohexane on a large scale. The research and development of high-efficiency cyclohexyl benzene hydrogenation catalyst should be further developed based on mature alkylation technology. This paper used an acidified USY molecular sieve to catalyze the alkylation of benzene and cyclohexene to cyclohexylbenzene, which achieved 100% conversion and selectivity. Furthermore, Pt/TiO2/γ-Al2O3catalyst is prepared by pre-deposition TiO2film of different thicknesses on γ-Al2O3surface and then supported with platinum particles by Atomic layer deposition (ALD). The role of TiO2film in improving the cyclohexylbenzene hydrogenation performance of the catalyst is studied. TEM, CO pulse chemisorption, CO-DRIFTs, quasi-in situXPS, H-D exchange, and H2-TPR characterization show that compared with Pt/γ-Al2O3, TiO2thin films on Pt/TiO2/γ-Al2O3do not change the dispersion of Pt particles, but can form new Pt-TiO2interactions. The hydrogenation performance of cyclohexylbenzene was improved by increasing the electron density and the proportion of planar active sites on the surface of platinum and reducing the energy barrier of hydrogen spillover. The research provides theoretical support for further bicyclohexane organic liquid hydrogen storage reagent development. The relevant metal-support interaction regulation strategy can be applied to the development of efficient catalysts for other aromatic molecules hydrogenation.

Carbon-based nanozymes with multifunctional applications have attracted enormous attention, however, there is still a lack of an effective strategy for inexpensive preparation of high-active carbon-based nanozyme. We herein report a waste paper-derived CoFe2O4/porous carbon nanozyme for the colorimetric detection of glucose and glutathione (GSH) in biofluids. The hybrid CoFe2O4/porous carbon material was successfully prepared via a combined impregnation, hydrolysis and carbonization method. Newly constructed CoFe2O4/porous carbon material with enhanced peroxidase-like activity could oxidize colorless tetramethylbenzidine (TMB) to blue oxidized TMB with adding H2O2. A sensitive colorimetric analysis platform for monitoring the levels of glucose and GSH in biofluids was respectively developed. The proposed analytical method possessed predominant features such as low limit of detections (LODs) (0.16 µmol/L for glucose and 120 nmol/L for GSH), broad linear ranges (1–200 µmol/L for glucose and 1–50 µmol/L for GSH), and excellent practical potential. This multipurpose platform not only provides a promising strategy for transforming waste paper into valuable carbon-based nanozyme, but also paves the way for excavating the potential biomedical and environmental applications from waste paper.

A variable geometry turbocharger in series with a variable geometry turbocharger (Twin-VGT) system was designed to improve engine power at high altitudes. The influence of altitudes on the performance of the Twin-VGT system was investigated in the perspective of available exhaust energy. The interaction between exhaust flow characteristics of Twin-VGT and openings of Twin-VGT vanes was theoretically analyzed at different altitudes. Meanwhile, a model of a diesel engine matched with the Twin-VGT system was built to study the matching performance of the Twin-VGT system with engine at different altitudes. The optimal opening maps of both high-pressure and low-pressure VGT vanes at high altitudes were obtained to achieve the maximum engine power. The results showed that the optimal openings of high-pressure and low-pressure VGT vanes decreased with increase in altitudes. The operating points of the two-stage compressors located at the high efficiency region and the compressor efficiency region both exceeded 62% at different altitudes. The global expansion ratio increased with increase in altitudes and reached 4.9 at 5500?m. Compared with the VGT in series with a fixed geometry turbocharger on testing bed, exhaust energy of Twin-VGT turbines at low speeds was utilized reasonably and global pressure ratio increased by 0.69–0.94, while brake-specific fuel consumption decreased by 11.24–33.62% under low speeds above altitudes of 2500?m.

To analyze the relative expression of PELI3 and its mechanistic involvement in the non-small cell lung cancer (NSCLC). PELI3 expression in NSCLC tissue samples was determined by the immunohistochemistry. The transcripts abundance of PELI3 was measured with real-time PCR. The protein intensity was analyzed by western blot. The overall survival in respect to PELI3 or miR-365a-5p expression was plotted by the Kaplan–Meier’s analysis. Cell growth was determined by colony formation assay. Cell viability was measured by MTT assay. The migration and invasion were evaluated by wound healing and transwell assay respectively. The regulatory effect of miR-365a-5p on PELI3 was interrogated with luciferase reporter assay. The direct binding between miR-365a-5p and PELI3 was analyzed by pulldown assay. PELI3 was aberrantly up-regulated in NSCLC both in vivo and in vitro. High level of PELI3 associated with poor prognosis. PELI3-deficiency significantly inhibited cell viability, colony formation, migration and invasion. We further identified that miR-365a-5p negatively regulated PELI3 in this disease. Ectopic expression of miR-365a-5p in both A549 and H1299 phenocopied PELI3-deficiency. Meanwhile, PELI3-silencing significantly abolished the pro-tumoral effect elicited by miR-365a-5p inhibition. Our results highlighted the importance of dysregulated miR-365a-5p-PELI3 signaling axis in NSCLC.

It is significant to study thermal balance of diesel engine under different variable geometry turbocharger (VGT) vane openings at variable altitudes, which is helpful to assess the heat distribution, control the heat load and improve the heat efficiency of the diesel engine. A thermal balance test system was built to study the influence of the VGT vane opening angles on a regulated two-stage turbocharged (RTST) diesel engine’s thermal balance performance. The experiment was conducted under full load operating conditions at different altitudes (0 m, 3500 m and 5500 m). Results indicated that the heat load of engine increased and the thermal efficiency decreased with the increase of altitudes under all operating conditions. As the VGT vane openings increased, the exhaust and maximum combustion temperature increased, while the maximum cylinder combustion pressure decreased. In particular, the maximum combustion temperature was more than 2000 K when the VGT vane openings were greater than 70% at the altitude of 5500 m, and the maximum combustion pressure exceeded 17 MPa when the opening of VGT vane was 70% at 0 m. The thermal efficiency of the engine decreased with the increase of VGT vane openings at the altitudes of 0 m and 5500 m, but the thermal efficiency increased and then decreased at the altitude of 3500 m. It was finally obtained that the best openings of VGT vane was 80%, 60% and 50% under the engine speed of 2100 r/min at 0 m, 3500 m and 5500 m, respectively.

The in-cylinder gas flow is an important factor that affects the engine performance. The appropriate swirl can reduce cycle-to-cycle variations, increase flame propagation speed, and improve the combustion efficiency. Many technologies can induce significant swirl, but lead to intake flow loss. In this research work, the variable valve lift difference adjustment mechanism is developed to obtain and adjust in-cylinder swirl without weakening flow capacity in a four-valve gasoline engine. The in-cylinder swirl and tumble characteristics generated by the variable valve lift difference adjustment mechanism are studied by means of experiment and simulation. The results of the experiment and simulation show the intensity of tumble and swirl under the larger lift valve is increased with the increase in the phase difference between two intake cams at same camshaft angle, and a large-scale swirl is formed in the cylinder when the camshaft angles change from 40° to 80°, and another large scale swirl is formed during the camshaft angles change from 100° to 140°, but the rotating direction of the secondary swirl is inverse to that of first swirl. The scale and shape of the in-cylinder tumble and swirl are not changed significantly with the increase in the phase difference between two intake cams when the camshaft angles change from 80° to 100°. A brief discussion on the research results that improve the performance of actual gasoline engine is given.

QoS-aware service composition problem has been drawn great attention in recent years. As an NP-hard problem, high time complexity is inevitable if global optimization algorithms (such as integer programming) are adopted. Researchers applied various evolutionary algorithms to decrease the time complexity by looking for a near-optimum solution. However, each evolutionary algorithm has two or more parameters, the values of which are to be assigned by algorithm designers and likely have impacts on the optimization results (primarily time complexity and optimality). The authors' experiments show that there are some dependencies between the features of a service composition problem, the values of an evolutionary algorithm's parameters, and the optimization results. In this article, the authors propose an improved algorithm called Service-Oriented Artificial Bee Colony algorithm considering Priori Knowledge (S-ABCPK) to solve service composition problem and focus on the S-ABCPK's parameter turning issue. The objective is to identify the potential dependency for designers of a service composition algorithm easily setting up the values of S-ABCPK parameters to obtain a preferable composition solution without many times of tedious attempts. Eight features of the service composition problem and the priori knowledge, five S-ABCPK parameters and two metrics of the final solution are identified. Based on a large volume of experiment data, S-ABCPK parameter tuning for a given service composition problem is conducted using C4.5 algorithm and the dependency between problem features and S-ABCPK parameters are established using the neural network method. An experiment on a validation dataset shows the feasibility of the approach.

Cobalt phosphide (CoP) has been emerging as alternative lithium-ion batteries (LIBs) anode in view of the outstanding thermodynamic stability and high theoretical capacity. However, the lithium storage behaviors were impeded by poor cycling and rate performance induced by huge volumetric changes of CoP anodes during Li+intercalation/deintercalation and the poor reaction kinetics caused by low electronic conductivity. Herein, the uniquely designed hemoglobin-like composites consisting of CoP nanoparticles coated by N, P-doped carbon shell (CoP@PNC) were prepared via a supramolecular self-assembly method, followed by the facile heat treatment process, which presented the amorphous phase. Based on the synergistic effects of rational nano/microstructure, double heterogeneous elements doped carbon substrate and amorphous phase, the transport paths of Li+and e−were shortened, the electronic conductivity was enhanced, the volumetric changes were effectively alleviated, resulting in outstanding electrochemical performance when applied as anode electrodes. The CoP@PNC electrodes deliver a capacity of 806.8 mAh g−1after 100 cycles at 0.1 A g−1and 523.9 mAh g−1after 3000 cycles at 2.0 A g−1. Furthermore, pseudo-capacitance behavior dominates the storage mechanism of CoP@PNC electrodes based on the quantitative kinetic analysis result that a high ratio of 66% in total capacity at 0.5 mV−1. This work illuminates the route to effectively relieve the huge volumetric changes to improve the electrochemical performance of transition metal phosphide and promote their practical application steps as electrodes for high energy density batteries.

The solubilities of ethane int-butanol (TBA) and water mixtures have been determined at 10, 15, and 20°C and pressures up to 3.1 MPa. Thermodynamic properties have also been calculated based on the measured solubility data and the hydrophobic interaction for the methane-methane pair interaction in the mixed solvent is discussed.

Abstract: The circular dichroism was used to study the complexation of two isoforms of rabbit liver apo-metallothioneins (apo-MT1 and apo-MT2) with Cd2+ ion and the influence of Cd2+ ion on the conformation of reconstituted MTs. The stability of sulfhydryls of apo-MT has been investigated at the room temperature in the presence of air. The reconstitutions of apo-MT1 with Cd2+ ion were carried out atpH 4.71 (stable state) andpH 7.9 (with 90% sulfhydryls oxidated) respectively. it was found that the characteristic CD band at 257 nm(+), 238 nm(−), 226 nm(+) of reconstituted MT with Cd2+ ion was the same as native MT atpH 4.71, however only one peak at 243 nm(+) appeared on the CD spectra atpH 7.9 which arose from mononuclear complexes with four separated thiolate ligands per Cd2+ ion. The CD spectra of apo-MTs+7 eq Cd2+ system were measured at variouspH values. It was found that the peak at 256 nm of apo-MT1 binding Cd2+ ion split into two small peaks atpH between 2.42 and 3.02, and became one peak atpH 3.32, while the shapes of Cd peaks of apo-MT2 binding Cd2+ ion did not change withpH, indicating that the binding sites and pathway of apo-MT1 binding Cd2+ ion were different from those of apo-MT2. A possible mechanism was suggested.

The total vapor pressures of dimethyl sulfoxide (DMSO) and water mixtures have been measured at 15, 20, 25 and 30°C. The activity coefficients and molar excess Gibbs energies of the system have been calculated. Possible association interaction in the system are discussed.

The solubilities of benzene and diphenyl in mixed solvents oft-butyl alcohol (TBA) and water atT= (298.15, 303.15, 308.15, and 313.15) K have been determined by spectrophotometry. The mole fractions of TBA in the mixed solvent arex= (0, 0.010, 0.020, 0.030, 0.040, 0.045, 0.050, 0.060, 0.080, and 0.150), respectively. The standard Gibbs energies of solution of benzene and diphenyl have been calculated based on the solubility data. The hydrophobic interaction (HI) for the pair benzene–benzene in the mixed solvent has also been calculated and discussed.

The solubilities of ethane in aqueous solutions of sodium dodecyl sulfate (SDS) were measured at 313.15 K and at pressures up to 3 MPa. The molalities of SDS (mSDS) in the aqueous solution were 0.0000, 0.0020, 0.0040, 0.0060, 0.0070, 0.0080, 0.0090, 0.0100, 0.0126, 0.0150, 0.0200, and 0.0300. The effect of SDS on the gas solubility in both concentration regions below and above the critical micelle concentration (cmc) was studied. The existence of the micelles of SDS in the solution is favorable to the dissolution of ethane due to the hydrocarbon-like interior of the micelles. The solubilities of ethane in each micelle at different pressures were evaluated based on some assumptions. It was found that the intramicellar solubility of ethane is less than that of the gas in n-dodecane. It was also found that the solubility of ethane in the micelles increases linearly with the partial pressure of ethane. The cmc of SDS was evaluated based on the solubility vs mSDScurves and the effect of dissolved ethane on the cmc was studied. It was observed that the cmc shifts toward a higher value with the increase in dissolved ethane.

ABSTRACTBackgroundIncreasing evidence indicates that gut microbiota plays an important role in cancer progression. However, the underlying mechanism remains largely unknown. Here, we report that broad-spectrum antibiotics (ABX) treatment leads to enhanced metastasis by the alteration of gut microbiome composition.MethodsCancer LLC and B16-F10 cell metastasis mouse models, and microarray/RNA sequencing analysis were used to reveal the regulatory functions of microbiota-mediated circular RNA (circRNA)/microRNA (miRNA) networks that may contribute to cancer metastasis.ResultsThe specific pathogen-free (SPF) mice with ABX treatment demonstrated enhanced lung metastasis. Fecal microbiota transplantation (FMT) from SPF mice or Bifidobacterium into germ-free mice significantly suppressed lung metastasis. Mechanistically, gut microbiota impacts circRNA expression to regulate levels of corresponding miRNAs. Specifically, such modulations of gut microbiota inhibit mmu_circ_0000730 expression in an IL-11-dependent manner. Bioinformatics analysis combined with luciferase reporter assays revealed reciprocal repression between mmu_circ_0000730 and mmu-miR-466i-3p. We further showed that both mmu-miR-466i-3p and mmu-miR-466 f-3p suppresses a number of genes involved in epithelial-mesenchymal transition (EMT) and stemness of cancer stem cells such as SOX9.ConclusionsThese results provide evidence of a previously unrecognized regulatory role of non-coding RNAs in microbiota-mediated cancer metastasis, and thus, the microbiome may serve as a therapeutic target.