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A new natural mycotoxin was isolated from the fermentation broth of Trichoderma sp. Jing-8 and the structure was determined as alternariol 1′-hydroxy-9-methyl ether (1), together with twelve known compounds. The structures were elucidated on the basis of their 1D, 2D NMR spectra and mass spectrometric data. Compounds 1, 8 and 9 indicated inhibitions against germination of the seeds of cabbage with MICs 1 showed the antibacterial activity against Bacillus subtilis and Staphylococcus aureus with MICs at 64 μg/mL. Compound 1 and 3 showed significant DPPH radical-scavenging activities with IC50 at 12 μg/mL, respectively. The OH at C-1′ in compound 1 decreased the cytotoxicity of these mycotoxins. A primary structure–activity relationship about the alternariol derivatives was discussed. Compounds 2–7 and 8 were the first time to be isolated from the Trichoderma.

A new meroterpenoid preaustinoid D ( 1 ) and a new neogrifolin derivative dihydroxyneogrifolic acid ( 2 ), together with other five previously reported meroterpenoids ( 3 - 7 ) were isolated from the endophytic fungus Penicillium sp. T2-8 associated with Gastrodia elata . The structures were elucidated on the basis of spectroscopic data analyses. It was the first time that neogrifolin and its derivatives were isolated from microorganism. Some of these meroterpenoids exhibited obvious antimicrobial activities in the microdilution antimicrobial assays.

Fourteen metabolites with various structure types were isolated from endophytic Chaetomium globosum. Five compounds were separated from genus Chaetomium for the first time. Some compounds exhibited remarkable inhibition against phytopathogenic fungi causing root rot of Panax notoginseng. Compounds 1–5 had significant DPPH-free radical-scavenging activity. Compounds 3 and 5 indicated significant inhibitions against the acetylcholinesterase (AChE). From preliminary structure–activity relationship, it was found that the oxygenic five-membered ring of 3 and 5 was crucial in the anti-AChE activity. These structures provide new templates for the potential treatment and management of plant diseases and Alzheimer disease.

Sensorless induction motor drives are widely used in industry for their reliability and flexibility. It’s very important to improve the performance of speed estimation in some cases, especial at low speed of IM drives. The authors have proposed and developed a model reference adaptive system (MRAS) based on discrete time sliding mode algorithm(DTSM), which has high performance for sensorless induction motor drive in low speeds. The new algorithm obtains the identification flux using the classic MRAS, and the PI adaptive law in MRAS is replaced with the sliding mode observer which is acquired by the error function. This paper presents the theory, modelling, simulation and experimental results of the proposed DTSM-MRAS based sensorless direct torque control induction motor drives.

With the increasing strictness of emission regulations, development direction of future diesel engines is toward the high thermal efficiency and low emissions. Supercharging technology is an important means for improving output power of diesel engines. This paper deals with the study of the two-stage turbocharging system of the non-road diesel engine. Based on GT-Power software code, a digital model of 6112 diesel engine was established. The supercharged model was calibrated by using the original experimental data. Then, four types of digital models with different two-stage turbocharging systems were constructed. The best two-stage turbocharging system was determined through investigating the impacts of different options on the performance of diesel engines. It was indicated through the study that two-stage turbocharging system can substantially increase the air flowing into the cylinder which increases the potential of power density. At the same time HC and NOx emissions can reduce. Through this study, a theoretical basis and an important reference for adopting the two-stage turbocharging system of the 6112 diesel engine were provided.

A new polyoxygenated farnesylcyclohexenone, peniginsengin A (1), was isolated from the fermentation of Penicillium sp. YIM PH30003, an endophytic fungus associated with Panax notoginseng (Burk.) F. H. Chen. The structure was assigned based on a combination of 1 D and 2 D NMR and mass spectral data. The cytotoxicity and antimicrobial activities of compound 1 were investigated.

One new gentisyl alcohol derivative and seven known compounds were isolated from the culture of Penicillium sp. Their chemical structures were elucidated by extensive spectroscopic analysis. Compounds 1, 4, and 6 inhibited Bacillus subtilis, Staphylococcus aureus, and Escherichia coli with MICs of 32–128 μg/mL.