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A general transition-metal-free photoinduced acetalation-pyridylation of alkenes using diethoxyacetic acid and cyanopyridine was developed under mild conditions. By employing 4CzIPN as the photocatalyst and Cs2CO3as the base, a diverse range of styrene derivatives and cyanopyridines worked well to give the desired products. The versatility of this method is highlighted by its application in the construction of various functional groups and the late-stage modification of drugs. Importantly, some of the synthesized compounds showed good in vitroantitumor activity, indicating that this protocol is of significance and potential for antitumor drug development.

Argonaute (AGO) proteins are the core of the RNA-induced gene silencing complex which regulate a wide variety of processes in plants, from organ development to abiotic stress responses. They have been identified in many plants, but little is known in longan (Dimocarpus longanLour.), and how AGOfunctions in the signaling pathways in plant embryos in response to changing environmental stimuli remains unclear. In the present research, a genome-wide analysis of the AGOgene family members and their roles in somatic embryogenesis (SE), zygotic embryogenesis (ZE), tissue developmental processes, and responses to hormones, light and abiotic stress in longan were conducted. Ten longan AGOgenes were identified genome-wide and divided into four clades. They were distributed on chromosomes 1, 4, 8, 10, 12, 13, 14, and 15, and had 2–23 introns. The expression profiling implied that DIAGOsregulated early and middle embryogenesis, as well as developmental processes of seed, flower, and stem in longan. In addition, the transcript levels of DIAGOsin response to exogenous hormones, light and abiotic stress showed differences in expression patterns. These results provide the useful information for further elucidation of RNAi-mediated gene silencing in longan embryogenic callus (EC).

A new seed-mediated growth technique for synthesizing gold nanorods (NRs) by using H2O2 as the weak reducer in the presence of a binary surfactant mixture is reported. Gold NRs prepared at different amounts of H2O2 and the gold seeds solution were characterized by transmission electron microscopy (TEM) and visible–near infrared spectroscopy. Gold NRs with tunable aspect ratio from 4.5 to 7 can be obtained and the corresponding longitudinal plasmonic wavelength of the produced gold NRs are tunable from 810 to 1140 nm. This method provides a new pathway for synthesis of gold NRs with a wide range of longitudinal plasmonic peaks, which have potential applications in optoelectronics and biomedicine.

Hydrogel bioelectronics as one of the next-generation wearable and implantable electronics ensures excellent biocompatibility and softness to link the human body and electronics. However, volatile, opaque, and fragile features of hydrogels due to the sparse and microscale three-dimensional network seriously limit their practical applications. Here, we report a type of smart and robust nanofibrillar poly(vinyl alcohol) (PVA) organohydrogels fabricated via one-step physical cross-linking. The nanofibrillar network cross-linked by numerous PVA nanocrystallites enables the formation of organohydrogels with high transparency (90%), drying resistance, high toughness (3.2 MJ/m3), and tensile strength (1.4 MPa). For strain sensor application, the PVA ionic organohydrogel after soaking in NaCl solution shows excellent linear sensitivity (GF = 1.56, R2> 0.998) owing to the homogeneous nanofibrillar PVA network. We demonstrate the potential applications of the nanofibrillar PVA-based organohydrogel in smart contact lens and emotion recognition. Such a strategy paves an effective way to fabricate strong, tough, biocompatible, and ionically conductive organohydrogels, shedding light on multifunctional sensing applications in next-generation flexible bioelectronics.

Direct, economical, and green synthesis of deuterated α-amino phosphine oxides remains an elusive challenge in synthetic chemistry. Herein, we report a visible-light-driven umpolung strategy for synthesizing deuterated α-amino phosphine oxides from isocyanide using 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene as the photocatalyst and D2O as the deuterium source. Moreover, the streamlined and sustainable methodology can be applied in the modification of amino acids, natural products, and drugs. The strong antiproliferative activity of the desired products indicates that the method could provide a novel privileged scaffold for antitumor drug development.

TiO2-Graphene nanocomposites were prepared by a wet chemical method and characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis). The nanocomposite demonstrated nice photocatalytic activity for water reduction to produce hydrogen. The optimal graphene content was found to be 10 wt%, giving a Hydrogen-production rate of 13.2 mmol∙h-1∙g-1, which significantly exceeded the rate observed on pure TiO2. This high photocatalytic H2-production activity is due to the deposition of TiO2 nanoparticles on graphene sheets, which act as an electron acceptor to efficiently separate the photogenerated charge carriers.

Practical BF3·Et2O catalyzed reactions between indoles and a series of carbonyl compounds at room temperature are described, which afford bis(indolyl)methanes with isolated yields up to 96%.

Effective benzylhalogenation triggered by in situprepared hypervalent halide.

Dilute sulfuric acid pretreatment of corn stover was used to obtain a solution of high concentration of xylose from the hemicellulosic fraction and a relatively low concentration of glucose, which not only saved the hemicellulase but also made a full use of corn stover. Then the study considered the selectivity (xylose-glucose ratio) as an important parameter to optimize the hydrolysis conditions. The results optimized by response surface methodology (RSM) showed that the optimum conditions for pretreatment were found to be H2SO4 concentration of 2.4% and reaction time of 100min at 100℃. Under these conditions, 78.8% of xylose yield was achieved and the glucose yield was lower than 11.6%. To confirm these results, the optimum condition was performed and the actual results of xylose yield and glucose yield were 78% and 11.3%.

Applying electroosmosis to sludge dewatering practically, methods for improving electroosmotic dewatering must be explored. The influence of initial pH, adding Al2 (SO4)3 dose and ash content in sludge on electroosmotic dewatering behavior was investigated. The results show that acid or alkaline environment is unfavorable for electroosmotic dewatering, especially initial pH of sludge closing to the isoelectric point, electroosmotic dewatering behaves worst. With increasing Al2(SO4)3 coagulant-aid dose, the decreasing rate of water content becomes slower gradually during electroosmotic dewatering. Besides, higher ash content in sludge has a better effect on vaccum filtration, but slightly impact on electroosmotic dewatering. When ash content increases to 69.9% from 52.4%, final water content reduces to 64.3% from 78.3% using vaccum filtration, and the decreasing amount of water content by electroosmotic dewatering ranges from 16.5% to 12.3%.

Powerline interference (PLI) often exhibits variations in frequency and amplitude, whose frequency lies in the spectrum range of the ECG signal. Most previous attempts of tracking time-varying PLI signal are based on Least Squared (LS) algorithm. This makes their methods susceptible to QRS complex in tracking low-level PLI signal. This study presents a new robust Kalman filter-based PLI suppressor to overcome the limitation of existing methods. M-estimation is incorporated into the kalman filter to combat the adverse effect of QRS impulsive. Simulation results indicate that our method outperforms the former LS-based PLI cancellers in both suppressing interference and preserving meaningful ECG components at various interference levels.

This paper summarizes the test method of ice-phobic coating adhesion strength and the progress in coating material. Ice adhesion strength of several commercial ice-phobic coatings were tested for Pratt & Whitney, and result indicated that reformative silicone R-2180 show significantly improved reduction in ice adhesion when compared to several different commercially available silicone-based ice-phobic coatings. It would be valuable in future studies to measure the surface energies of the several materials tested to determine any correlation between the ice adhesion and surface energy of the coating.

According to the characteristics of the design process of top-down collaborative assembly design, process planning dynamic model based on HOOPN (hierarchical object-oriented Petri-net) is constructed for top-down collaborative assembly design. The outside and inside task dependent relationships among the task groups include parallel, sequence and coupling are implemented. The definitions of attribute for each element and the activation rules are presented for Petri-net. The fuzzy overall evaluation model is applied for risk evaluation of design process, and the local and global risk level is determined. The whole process planning is adjusted and controlled based on special risk decision-making mechanism.

Because anthropogenic nitroaromatic compounds have entered the biosphere relatively recently, exploration of the recently evolved catabolic pathways can provide clues for adaptive evolutionary mechanisms in bacteria. The concept that nitroarene dioxygenases shared a common ancestor with naphthalene dioxygenase is well established.