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We developed a visible-light-driven expanded EDA complex profile for the synthesis of aza-arenes via aza-6π electrocyclization of 2-styrylanilines with aromatic aldehydes. This protocol relies on the EDA complexes of AlCl3with imine to induce the absorption red-shift to visible light from ultraviolet light. An array of 2,3-disubstituted quinolines were constructed smoothly after excitation with blue-light-emitting diodes at room temperature. In addition, the resultant product, used as a cell permeable lipid droplet-specific probe, shows a low working concentration, a short staining time, and functionality in living and fixed cells.

The development of a novel environmental benign and sustainable synthetic method for highly efficient construction and direct C–H functionalization of N-heterocycles remains a pivotal central research topic for organic and medicinal chemistry. Herein, a novel visible-light-enabled biomimetic aza-6π electrocyclization for efficient assembly of diverse pyridines and further tandem Minisci-type reaction were developed. A broad spectrum of polysubstituted picolinaldehydes were readily constructed with high efficacy and good functional group tolerance under metal- and oxidant-free conditions.

Organic-inorganic hybrid perovskite has been verified as a suitable semiconductor for hot carrier solar cells via transient absorption spectroscopy. Recently, an internally photoemitted hot carrier (IPHC) solar cell with a novel and innovative structure based on organic-inorganic hybrid perovskite has been achieved. This is a breakthrough in hot carrier study based on perovskite material. To further improve the performance of this newly developed hot electron collection device, a simple and efficient method of adding lithium fluoride (LiF) surface modification layer was applied onto the outmost perovskite layer that benefits both reduction of the trap states and formation of interface dipoles. The IPHC device with LiF modification layer shows a remarkable increase of the short-circuit current density with 20.31% increment. This successful interface engineering proposes a new guideline for further optimizing the performance IPHC and also traditional solar cells based on perovskite.

Despite the preferential use of titanium dioxide (TiO2) as electron transport layers (ETLs) for perovskite solar cells (PSCs), some problems are still needed to be solved to achieve better power conversion efficiency (PCE). Herein, TiO2nanotubes (TD-NTs) with network structures have been obtained through an inexpensive hydrothermal strategy. The obtained TD-NTs have been used in constructing PSCs as a favorable interface ETL. The PSC based on TD-NTs displayed a high PCE of 19.14%, increased by 11.4% compared to 17.18% for TiO2nanoparticles (TD-NPs) as a reference under the same conditions. The benefits beyond the amalgamation of nanotube structures are suppression of charge recombination and reinforcement of the transport pathways for carriers. The stability tests have shown that the cells with the TD-NT network maintain over 90% of their efficiency even after more than 500 h, much better than that of normal nanoparticle-based ones. Overall, TD-NT-ETL has demonstrated its potential in efficient and stable PSCs.

Poly(3,4-ethylenedioxythiophene)/polystyrene sulfonate (PEDOT:PSS) plays an important role in inverted planar perovskite solar cells (IPPSCs) as an efficient hole extraction and transfer layer (HTL). The IPPSCs based on PEDOT:PSS normally display inferior performance with a reduced open-circuit voltage. To address this problem, here sodium citrate-doped PEDOT:PSS is adopted as an effective HTL for improving the performance of IPPSCs. Sodium citrate-doped PEDOT:PSS HTL improves the conversion efficiency of IPPSCs from 15.05% of reference cells to 18.39%. The large increase of the open-circuit voltage (VOC) from 1.057 to 1.134 V is the main source for this performance enhancement. With the help of characterization analysis of ultraviolet photoelectron spectroscopy, scanning electron microscopy, electrochemical impedance spectroscopy, etc., the higher work function of the doped PEDOT:PSS film and the uniform crystallinity of the perovskite film on it are disclosed as the reasons for the increased VOCand the consequent performance enhancement.

A dynamic secondary cooling control model was developed to improve the quality of slab casting by combining the thermal transition computation method and proportional integral derivative (PID) controlling technology in continuous casting. The calculation principles, characteristics, and controlling parameters of the dynamic secondary cooling control model are described. The model automatically adjusts the secondary cooling flow according to slab casting parameters and maintains the slab surface temperature close to the target value. The reliability and usefulness of the secondary cooling control system are improved by quickly adjusting and stabilizing the secondary cooling flow. Online monitoring of temperature shows that the model is precise, and the surface cracks and central segregation were found to improve in the slabs. The model has been successfully applied to several continuous casters at Baosteel.

A dynamic secondary cooling control model was developed to improve the quality of slab casting by combining the thermal transition computation method and proportional integral derivative (PID) controlling technology in continuous casting. The calculation principles, characteristics, and controlling parameters of the dynamic secondary cooling control model are described. The model automatically adjusts the secondary cooling flow according to slab casting parameters and maintains the slab surface temperature close to the target value. The reliability and usefulness of the secondary cooling control system are improved by quickly adjusting and stabilizing the secondary cooling flow. Online monitoring of temperature shows that the model is precise, and the surface cracks and central segregation were found to improve in the slabs. The model has been successfully applied to several continuous casters at Baosteel.

Based on the characteristics of high fluctuation and periodicity of output power during working process of wheel loader, hybrid drive technology can provide a solution for fuel saving and fuel reduction of wheel loader through power adjustment function and energy recycle feature. Aiming at power output motion of wheel loader duty cycle, 7 means for hybrid wheel loader to save fuel have been proposed; contribution to save fuel and easiness to realize the goal under current technical conditions of each means has also been assessed. It is considered that there are two categories of wheel loader energy saving technology: one is to increase fuel utilization rate, and the other is improve transmission efficiency of torque converter. However, realizing one of these two aspects can not save fuel ideally; improvement in both aspects will bring satisfactory energy materials saving effects.

A direct esterification synthesis of glucose undecylenic acid sugar monoester is described, using the immobilized lipase enzyme NOVO-435 in 2-methyl-2-butonal and in ethyl methyl ketone (EMK). conditions were optimized in order to produce the monoester more rapidly and in higher yield. After the reaction product was purified, mass spectroscopy revealed that it had a molecular weight of 346.2 AMU. Further characterization by 1H and 13C NMR spectroscopy was carried out, including two-dimensional (2D) 1H-1H COSY and heteronuclear 1H-13C HSQC experiments. These data enabled identification of the monoester product to be 6-O-(10-undercylenoyl)α-D-glucose (74%), and 6-O-(10-undercylenoyl)β-D-glucose (26%) in methanol solution.

Hydraulic excavator energy saving is one of the dominating problem that trouble construction machinery industry. Hybrid technology brings forward a new solution for this puzzle. In the research of hybrid hydraulic excavator, we set up a parallel hybrid excavator test bench based on modular-design method, this fills a domestic technology gap. Power-train performance test is undertaken on this bench and the power assist control strategy is proved to be significant energy saving.

In this paper the electric-hydraulic servo system for excavating robot is analysed. The kinematic and the dynamic model of working equipment are established. Aim at the electric-hydraulic servo system of the feature with many variables, strong coupling and non-linear, the CMAC neural network was presented combined with popular PD algorithm, which could realize intelligent control for the working equipment of excavating robot. The result of simulation show that control strategy features higher precision and robustness.

The theory of the excavator’s hydraulic system was elaborated in the paper taking a 20t hybrid hydraulic excavator produced by a domestic company for example. The rotary movement of the hybrid hydraulic excavator was achieved by a newly developed electric motor, fuel consumption could be reduced as the result of the speed inhibition when the excavator standby. The modeling of excavator’s hydraulic system, front-end attachments and revolving frame were built on the AMESim platform according to the installation and actual sizes of the hydraulic components. By setting the parameters of every component in the model, mechanical- electronic- hydraulic integrated simulation was achieved. The paper focused on the solutions of hydraulic system’s pressure fluctuation and poor simulation results of front-end attachments. As a conclusion, appropriate solutions and simulation results were proposed to improve the precision.

After analyzing the loader duty cycle with hybrid drive theory and gaining the characteristics of loader duty cycle, an integrated started generator-ISG based coaxial parallel hybrid loader is designed. Two simulation models are built with the simulation software Cruise, one is tradition loader another is hybrid loader. The simulation result of tradition loader model compare with the test data to amend the model. To gain same accuracy, the hybrid loader model is rebuilt based on the tradition loader model. According to the “I” type duty cycle, comparing the simulation result of tradition and hybrid loader, the result shows that hybrid loader can save fuel 10.4%.

Ganz einfachlassen sich Filme aus Graphen‐ und Quantenpunkt(QD)‐Schichten aus wässrigen Lösungen auf transparenten leitfähigen Indiumzinnoxid(ITO)‐Substraten aufbringen. Graphen eignet sich dank seiner Struktur und günstigen Austrittsarbeit gut für die Sammlung und Übertragung durch Licht erzeugter Ladungen auf die Elektrode; als Resultat erhält man ein hocheffizientes Photovoltaikelement (siehe Bild; IPCE=Photostromeffizienz, SWNT=einwandige Kohlenstoffnanoröhre).

This paper present an analysis of the mechanics characters of a safety structure with steel liner under near blasting load, by the methods of numerical study. Through the ANSYS/LS-DYNA numerical analysis, we get the reasonable thickness and position location of steel. This paper put forward the curve of the steel at different thickness and position in the safety structure, that provide a reference to the designing of the safety structures and other relevant project.

Since the broken phenomenon is always appeared in the roof of mine roadway, it largely affects the roadway’s roof stability. With Material Mechanics theory, the authors expound bolt tail subjected to no center load action and roof bolt broken mechanism while roadway is supported with bolts. By theoretical analysis and Lab test, the paper puts forward a kind of new type bolts which may prevent bolt tails from being broken, bolt construction structure’s pattern, and bolt made technology. It is illustrated that the reasonable grading relationship between bolt body’s iameter and bolt tail’s screw diameter. At same time, the authors compare disturbed values of the thick tail metal bolt and common bolt under the load action. It is verified that roof bolt broken problem may be solved with new type’s thick tail bolt. Therefore, the new type bolts have a wide application in the future.

Two novel polymers with naphthalimide pendant groups have been prepared. In poly(2-methylacrylic acid 2-[6-(4-methylpiperazin-1-yl)-1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinolin-2-yl]ethyl ester-co-methyl methacrylate) (copolymer 1), an alkylated tertiary amine acts as an electron donor and quenches the fluorescence of the naphthalimide fluorophore via the photo-induced electron transfer (PET) process. Protonation of the alkylated tertiary amine by an acid generated by a photoacid generator (PAG) can switch off the PET path and the fluorescence of the naphthalimide fluorophore would be recovered and enhanced. For poly(2-methylacrylic acid 2-[6-(4-methylpiperazin-1-yl)-1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinolin-2-yl]ethyl ester) (polymer 3), protonation both of the aromatic amine and the alkylated amine by the acids generated from may result in significant fluorescence quenching and alter the fluorophore. When protonation processes occur, the fluorescence enhancement (×2) of copolymer 1 or the fluorescence quenching (×15) of polymer 3 would be applied to generate positive or negative fluorescent patterned images on their net films.

ABSTRACT: Many of the neurotrophic factors promote the survival of developing peripheral sensory neurons, and they might be useful as therapeutic agents in the adult neuronal systems. During development, neurotrophin‐3 (NT‐3) and brain‐derived neurotrophic factor (BDNF) mRNAs are expressed in the auditory sensory epithelium, which composes the peripheral target field of the cochlear (spiral) neurons. NT‐3 mRNA is also expressed in the inner hair cells of the mature organ of Corti. mRNAs encoding their signal‐transducing receptors, TrkC and TrkB, respectively, are expressed in the cochlear neurons. In addition to neurotrophins, which seem to have an important role during development, another neurotrophic factor, glial cell‐line‐derived neurotrophic factor (GDNF), seems to be involved in the maintenance of postnatal auditory neurons. In the present work, the cellular distribution of neurotrophins and GDNF in the developing and adult rat inner ear are compared. The effects of recombinant neurotrophins and GDNF on dissociated cochlear neurons in vitroare also compared. Recently, NT‐3 and BDNF were used in vivoas therapeutic agents to protect guinea pig cochlear neurons from aminoglycoside‐induced degeneration and GDNF from noise‐induced degeneration. These data demonstrate that NT‐3, BDNF, and GDNF might be potential candidates for prevention of degeneration of the auditory nerve in man.

We studied the expression of neurotrophins and their Trk receptors in the chicken cochlea. Based on in situ hybridization, brain-derived neurotrophic factor (BDNF) is the major neurotrophin there, in contrast to the mammalian cochlea, where neurotrophin-3 (NT-3) predominates. NT-3 mRNA labeling was weak and found only during a short time period in the early cochles. During embryogenesis, BDNF mRNA was first seen in early differentiating hair cells. Afferent cochlear neurons expressed trkB mRNA from the early stages of gangliogenesis onward. In accordance, in vitro, BDNF promoted survival of dissociated neurons and stimulated neuritogenesis from ganglionic explants. High levels of BDNF mRNA in hair cells and trkB mRNA in cochlear neurons persisted in the mature cochlea. In addition, mRNA for the truncated TrkB receptor was expressed in nonneuronal cells, specifically in supporting cells, located adjacent to the site of BDNF synthesis and nerve endings. Following acoustic trauma, regenerated hair cells acquired BDNF mRNA expression at early stages of differentiation. Truncated trkB mRNA was lost from supporting cells that regenerated into hair cells. High levels of BDNF mRNA persisted in surviving hair cells and trkB mRNA in cochlear neurons after noise exposure. These results suggest that in the avian cochlea, peripheral target-derived BDNF contributes to the onset and maintenance of hearing function by supporting neuronal survival and regulating the (re)innervation process. Truncated TrkB receptors may regulate the BDNF concentration available to neurites, and they might have an important role during reinnervation. © 1997 John Wiley & Sons, Inc. J Neurobiol 33: 1019–1033, 1997

Hot carriers and their extraction have been demonstrated in organic-inorganic perovskites under transient condition. Unfortunately, there was no real device to harvest hot carriers under steady-state illumination yet due to the indistinguishable hot and cooled carriers in conventional sandwiched structure. Here we report a new designed architecture based on internally photoemitted hot carrier (IPHC) solar cell, whose active CH3NH3PbI3layer is outside of the two collection electrodes with configuration of CH3NH3PbI3/Au/TiO2/FTO. Herein, the photoexcited hot electrons transfer ballistically from CH3NH3PbI3layer to TiO2via thin gold layer for electron collection. For the first time, the device we fabricated using this novel structure produces short circuit current of 5422 μA cm−2under one sun (100 mW cm−2) illumination which demonstrates the efficient harvesting of hot electrons under steady-state sunlight illumination. The considerable efficient photocurrent showed by this new design opens an alternative approach for light-to-electricity conversion.