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Fluid catalytic cracking (FCC) is an important process in petroleum processing. Effective monitoring of the status and quality of FCC is vital. Accurate description of the relationship between process and quality variables is the basis of quality-driven monitoring. Many process variables affect the quality of FCC; some of these effects are linear, and others are nonlinear. We propose a combination method from the perspective of linearity and nonlinearity to improve the monitoring performance of FCC quality. Partial least squares (PLS) is initially used to extract linear features, and its residual space is saved as the input of the deep feedforward neural network (DFNN). DFNN is then used to extract nonlinear features for the further decomposition of subspaces. The PLS-DFNN method accurately describes processes involving linearity and nonlinearity. We construct three monitoring statistics to characterize the types of faults. The proposed method proves its excellent effect on a numerical simulation data set. It effectively distinguishes the types of faults on the Tennessee Eastman process data set, and the fault detection rate is superior to other related methods. Finally, we apply this method to the actual FCC and verify the superiority of this combination. [ABSTRACT FROM AUTHOR]

Despite that radiotherapy (RT) is a prevalent treatment of cancer, enhancing tumor dose deposit and reversing resistance are two major challenges in its clinical application. Here, we report Au–ZnO (AZ) nano matches that drastically increase reactive oxygen species (ROS) generation and alleviate hypoxia in RT on triple-negative breast cancer. Upon X-ray irradiation, Au increases X-ray attenuation and excites the adjacent ZnO by electron scattering, electron transfer, and energy transfer. Meanwhile, Au plays the role of a reservoir of electrons that promotes the charge separation in ZnO, thereby significantly improving the ROS production efficiency and causing the ROS burst. The ROS generation efficiency of AZ is determined to be 2.03 times that of Au. In contrast, a physical mixture of Au and ZnO only slightly increased the ROS generation compared to Au (1.18 times). Moreover, AZ catalyzes H2O2 decomposition to produce oxygen at excited states, thus modulating tumor hypoxia. Clonogenic assay showed that AZ had efficient radiosensitization with radiation enhancement factors of 4.01 and 3.50 in 4T1 breast cancer cells under normoxia and hypoxia, respectively. AZ-enhanced RT can successfully eliminate or shrink tumors (two of the six were completely removed) upon 4 Gy of X-ray irradiation on 4T1 tumor-bearing mice. At the end point, the average tumor size in AZ with the RT-treated group was only 1.8% of that of PBS with RT, significantly outperforming the other control groups including a physical mixture of Au and ZnO nanoparticles at the same concentrations.. [ABSTRACT FROM AUTHOR]

Very recently, transition metal phosphides (TMPs) have emerged as low-cost and robust co-catalysts for decorating graphitic carbon nitride (g-C3N4) for photocatalytic hydrogen (H2) evolution. However, to date, little work has been done regarding the decoration approaches to hybridize TMPs on the g-C3N4 surface with homogeneous dispersion and intimate interfacial contact. Herein, we present a facile and convenient route to in situ incorporate g-C3N4 nanosheets (NSs) and Ni2P nanocrystal (NC) co-catalysts via a one-step co-heating solution approach. The Ni2P/g-C3N4 (in situ) hybrid photocatalyst achieved a far superior H2 production rate (2849.5 μmol g−1 h−1) and durability (no decrease after 4 cycles of reaction within 20 h) compared to the Ni2P/g-C3N4 (self-assembly) sample. The apparent quantum yield (AQY) of 18.8% at 420 nm was also much higher than that of other TMP co-catalyst loaded g-C3N4 hybrid photocatalysts. A possible Ni(δ+)–N(δ−) chemical coupling in the Ni2P/g-C3N4 (in situ) hybrid composite was proposed and corroborated by X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy. The unique Ni(δ+)–N(δ−) chemical bonding states between g-C3N4 and Ni2P significantly accelerate the photo-generated charge-carrier separation and extraction from g-C3N4, as well as maintaining the H2 production durability. We believe that the hybridization route presented in this work will be extended to construct other TMP integrated photocatalysts toward efficient and stable solar water splitting. [ABSTRACT FROM AUTHOR]

A catalyst‐free strategy has been established for the synthesis of β‐oxo sulfones via visible light‐induced oxysulfonylation of alkenes with arylazo sulfones with dioxygen in air. The present photoinduced transformation proceeds smoothly at room temperature in the absence of an external photosensitizer, which not only provides a mild and efficient approach to various β‐oxo sulfones, but also opens a different reaction mode for the photochemical reaction of arylazo sulfones. [ABSTRACT FROM AUTHOR]

An innovative intensified vitamin E (VE) recovery process from the methylated oil deodorizer distillates (MODDs) was proposed, where VE was in situ transferred into a deep eutectic solvent (DES) with an organic salt. To design the process, the chlorine based quaternary ammonium salts were primarily investigated, and [N4,4,4,4]Cl was selected as an association solvent which can efficiently form DES with α-tocopherol of the representative compound of VE. Based on the determined phase diagram of the DES freezing points, four phase regions were classified, and the effect of the [N4,4,4,4]Cl/tocopherol ratio and temperature on the extraction performance and phase transformation was figured out. Moreover, an intensified association extraction process via in situ forming DES of α-tocopherol with [N4,4,4,4]Cl was designed and validated by experiments. VE products were finally obtained from both model MODD (purity of 99.63%) and practical MODDs (purity of >79.18%), which verifies the excellent extraction efficiency for the proposed recovery method. © 2016 American Institute of Chemical Engineers AIChE J, 63: 2212-2220, 2017 [ABSTRACT FROM AUTHOR]

A metal-ion-mediated cyclization of a linear peptide to the corresponding cyclohexadepsipeptide, a stereoisomer of �hirsutellide A, was studied. The presence of AgBF4 improved the cyclization yield from 14% to 61%. The effect of silver ion on the macrocyclization was further investigated by NMR and molecular mechanics calculations. [ABSTRACT FROM AUTHOR]

A facile and efficient approach to the synthesis of secondary thioamides from ketoximes via Beckmann rearrangement has been established, using phosphorus pentasulfide as a dehydrating and thiating agent. It is also efficient for the preparation of primary thiobenzamide from benzaldoxime. This approach features simple-operation, easy-control and good to excellent yields. [ABSTRACT FROM AUTHOR]

A novel domino cross dehydrogenative coupling of 2-aryl acetals with unmodified ketones has been developed, using DDQ as both the oxidant and reactant precursor. [ABSTRACT FROM AUTHOR]

Inverted MAPbI3 Perovskite Solar Cells with Graphdiyne Derivative-Incorporated Electron Transport Layers Exceeding 20% Efficiency In article number 1900241, Tonggang Jiu and co-workers introduce chlorine-substituted graphdiyne into MAPbI SB 3 sb -based perovskite solar cells to produce a peak efficiency of 20.34% with suppressed J-V hysteresis, which results from the interaction of derivated graphdiyne and PCBM, to be exact, four types of non-covalent bonds. These findings suggest that derivated graphdiyne could have potential applications in solar cells and other photoelectric devices. [Extracted from the article]

Chlorine‐substituted graphdiyne (ClGD) is employed into electron transport layers (ETLs) of MAPbI3‐based perovskite solar cells for the first time, forming a high‐quality film with superior film morphology and electrical conductivity as compared with pristine [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) film. Strikingly, a champion power conversion efficiency of 20.34% is achieved, showing a 19% enhancement compared with the counterparts (17.08%). Simultaneously, ClGD‐PCBM‐based devices show suppressed J–V hysteresis. It is experimentally and theoretically demonstrated that the interactions of derivated graphdiyne and PCBM stem from four types of noncovalent bonds, which contribute to the improved device performance. The results suggest that derivated graphdiyne‐based interfacial material is promising for the applications in solar cells and other photoelectric devices. [ABSTRACT FROM AUTHOR]

Graphdiyne‐ZnO (GDZO) composite material is prepared via a simple method and studied in detail for the first time. The transmission electron microscopy, Raman spectroscopy and X‐ray photoelectron spectroscopy (XPS) analyses confirm the formation of an adduct between GD and ZnO. Then the interaction between ZnO and GD is further investigated by first‐principles calculations. It is found that the Zn and O atom can coordinate bonding with GD, thus forming the CZn bond and CO bond, respectively. Polymer solar cells are fabricated based on the nanocomposites for the first time and an enhanced power conversion efficiency of 11.2%, compared with the devices with ZnO‐only (10%), is obtained. Simultaneously, the resultant devices show better stability, whether in glove box or in atmosphere, with humidity of 90%. The investigation of exciton generation rate, ideal current‐voltage model, and impedance spectra verify that the introduction of GDZO not only accelerates electron transfer but also reduces charge recombination occurring at the interface. The results indicate that GDZO is a promising electron transport material to enhance solar cell performance and presents a large potential for optoelectronic applications as well. Graphdiyne‐ZnO composite material is prepared via a simple method and studied in detail. Zn and O atoms can coordinate bonding with graphdiyne, thus forming the CZn bond and CO bond, respectively, which improves the morphology and electrical conductivity of the interfacial layer. Polymer solar cells based on the nanocomposites obtain an enhanced power conversion efficiency of 11.2% compared with the devices with ZnO‐only (10%). [ABSTRACT FROM AUTHOR]

Satellite networks provide complete connectivity and worldwide data transmission capability for constructing the Internet of Things. However, because of the varying Internet of Things traffic density, satellite networks may endure imbalanced traffic requirements and frequent link congestion. To effectively resolve these problems and optimally transmit Internet of Things data, a novel hybrid global-local load balancing routing scheme for Low Earth Orbit satellite networks is proposed in this article. Hybrid global-local load balancing routing scheme enables satellites to route Internet of Things traffic through global planning and local real-time adjustments in two steps. In hybrid global-local load balancing routing scheme, given the predictive nature of Internet of Things traffic distribution and Low Earth Orbit satellite networks, the inter-satellite traffic demand is decomposed into a predictable long-range baseline and unpredictable short-range fluctuations. A global strategy is employed first for preliminary global traffic allocation based on long-range baselines, and a local strategy is then employed for route adjustments based on short-range fluctuations. With the combination of global planning and local real-time adjustments, network traffic can eventually obtain a near-optimal allocation. Numerical simulations indicate that in contrast to single-strategy schemes, hybrid global-local load balancing routing scheme can more thoroughly eliminate congestion, and it performs better in measures such as packet loss rate, average queuing delay, traffic distribution, route oscillation, and communication overhead. [ABSTRACT FROM AUTHOR]