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1-Benzyloxy-2-iodo-4-tert-octylbenzene was synthesized with new methods from 4-tert-octylphenol via bromination, benzyl protection and halogen exchange reaction. Improved yield and easy purification benefit this method. The effects of solvents and ligands in halogen exchange reaction were studied in detail. The synthesized 1-benzyloxy-2-iodo-4-tert-octylbenzene was further examined for its application in Ullmann coupling reaction for preparation of 1-benzyloxy-2-(3,6-di-tert-butyl-9H-carbazolyl)-4-tert-octylbenzene. These newly synthesized compounds were characterized by IR, GC, 1H NMR, 13C NMR, GC–MS and HRMS.

A new series of imine–Pd–(N-heterocyclic carbene) complexes have been developed as efficient catalysts for Pd-catalyzed Suzuki–Miyaura coupling reaction. Based on the performance of supporting ligands, correlation of structure and catalytic activity has been demonstrated via experimental and computational modeling. A broad reaction scope of aryl and heteroaromatic chlorides could proceed at extremely low catalyst loading (minimum 0.005 mol %).

A new structure of saturated ring skeleton monoligated NHC-Pd-Imine complex was easily synthesized and unambiguously confirmed by X-ray single crystal diffraction. It was found to be an efficient and air-stable catalyst for the α-arylation of ketones. The reaction could be operated in air without any negative effect. Non-activated aryl and heteroaryl chlorides have been successfully applied in the reaction with only 0.5 mol% catalyst loadings under air atmosphere. Excellent to good product yields were afforded.

The traditional physical experiment teaching mode has already hindered the cultivation of creative talents seriously, Introduce the conceptual teaching method to the experimental class of physics will create a completely new physics experiment teaching mode, This article introduce the method of conceiving teaching and the function of training students’ ability of thinking independently, creation, analysing and solving problems.

An innovative fresh-keeping method for aquatic products is presented in this article. Spanish mackerel (Scomberomorus niphonius) were treated with a high-voltage electric field (HVEF) at different voltages and times and then stored in a refrigerator at 4°C. Bacteria count, total volatile basic nitrogen (TVB-N), sensory index, proximate composition, and pH were measured to evaluate the fresh-keeping effect of the proposed method. Results indicate that HVEF can restrain bacteria growth, reduce TVB-N, and delay sensory score decline; and that 45 kV for 20 min is the optimal treatment parameter of HVEF for extending Spanish mackerel shelf life. Results also suggest a potential application for HVEF treatment in aquatic products preservation.

In order to improve the drying rate and to reduce the energy consumption of aquatic product, sea cucumber were treated with high pulse electric field (HPEF) in different frequency, and different voltage. The hot air drying rate of treated sea cucumber was determined and, meanwhile, several quality parameters such as the shrinkage and rehydration rate of samples with pretreatment were determined to compare with those of untreated samples. The results indicated that the hot air drying rate and rehydration rate of sea cucumber can be improved and the shrinkage of sea cucumber can be decreased by HPEF pretreatment, and while HPEF pretreatment was applied for 22.5kV at a frequency of 70Hz, the drying rate could be increased approximately 58%.

To improve the drying rate and to reduce the energy consumption of aquatic product, scallop muscle were treated with high pulse electric field (HPEF) in different frequency, and different voltage. The hot air drying rate of treated scallop muscle was determined, meanwhile, several quality parameters such as the shrinkage and rehydration rate of samples with pretreatment were determined to compare with those of untreated samples. The results indicated that the drying rate of scallop muscle can be improved by HPEF pretreatment without affecting the quality, and 22.5kV for pretreatment voltage and 50Hz for pretreatment frequency is the optimum treated parameters.

A new series of imine–Pd–(N-heterocyclic carbene) complexes have been developed as efficient catalysts for Pd-catalyzed Suzuki–Miyaura coupling reaction. Based on the performance of supporting ligands, correlation of structure and catalytic activity has been demonstrated via experimental and computational modeling. A broad reaction scope of aryl and heteroaromatic chlorides could proceed at extremely low catalyst loading (minimum 0.005 mol %).

In order to develop a highly efficient drying technique for shrimp, a combination of air drying (AD) and vacuum freeze drying (FD) is examined. The drying rate of combination drying, the shrinkage, rehydration ratio, and sensory properties, such as the color and trimness, of the dried product in the AD–FD method are measured. Compared with FD, the combined process consumes less drying time, compared with AD drying alone. Also the product processed by combined drying displays lower shrinkage, higher rehydration rate and better sensory qualities.

Electrohydrodynamic (EHD) drying was tested as an improved dehydration method for scallop muscle. The scallop muscle was dried in an EHD drying system at 15°C, in an oven at 60°C, and in ambient air at 15°C. The energy consumption of EHD and oven drying, as well as the shrinkage rate, water absorption, solid loss, and sensory properties such as color and anti-crushing durability of the dried scallop muscle were measured. Results showed that the drying rate of scallop muscle significantly improved using the EHD drying system. Under a 45 kV voltage, the drying rate of EHD is 7 times higher compared with that of air drying in the 1st h. Compared with oven drying, EHD drying was more efficient in terms of energy saving. Furthermore, EHD drying cost only 28.67% of the electric energy required for oven drying. The dried scallop muscle by EHD had better sensory qualities and higher anti-crushing durability. EHD drying is very advantageous and can be used as a substitute to the traditional drying method.

Single-walled conjugated microporous polymer (CMP) nanotubes containing alternative phenylene and ethynylene units were described computationally for the first time in this work. The electronic structures and adsorption properties were studied by the density-functional tight-binding method augmented with a van der Waals dispersion term. Our calculations show that the morphology of CMP influences the benzene-adsorption performance significantly. The tubes show smaller binding energies to benzene molecule than the film counterparts, consistent with the observation of low adsorption capacities of tubular materials in our experiments. Enlarging the linker or adding substituents in the node can both reduce the tube's band gap. The introduction of OH or NH2 substituents in the tube node increases the binding strength between the adsorbent and the adsorbate, which is energetically favorable to enhance the adsorption capacity. Our results are expected to provide theoretical insights into the rational design of novel CMP nanotubes with improved adsorption capacities for organics.

The study showed that 2 450 MHz microwave irradiation for 35 seconds or more had significant death effects on Moina mongolica Daday. Short-term (less than 25 seconds) microwave irradiation could obviously increase the larvae number per clutch and the total fecundity over life span of the animal, with the highest fecundity under 10 seconds irradiation. Microwave irradiation could significantly prolong the life span (15.8-18 d) of M. mongolica. The short-term microwave irradiation had less effect on the development of larvae animal, but inhibited the adult growth to some degree. Impulse electromagnetic field could significantly increase the fecundity of M. mongolica, with the highest effect of 29 kV x cm(-1); while high-voltage electrostatic field had less effect on the reproduction of M. mongolica. Both high-voltage and impulse electrostatic fields had no remarkable effects on the development of larvae animal. High-voltage electrostatic field had less effect on the growth of adult animal; while impulse electromagnetic field had definite inhibition effect on it, and the inhibition effect was increased with increasing voltage.