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The protease hydrolysis technology is used to extract the polypeptides from the sea cucumber waste liquid. The enzymatic hydrolysis ability of protein in sea cucumber waste liquid by seven proteases shows that the best protease is compound protease by taking the hydrolysis degree as the index. Furthermore, the effects of enzyme dosage, pH, temperature and time of enzymatic hydrolysis on the hydrolysis degree are studied, and Box-Benhnken central composite test and response surface analysis method are used to optimize the enzymatic hydrolysis conditions.. The results show that the optimal enzymatic hydrolysis conditions are: enzyme dosage: 647 U/g; pH: 6.48; temperature: 52.5°C; enzymatic hydrolysis time: 3.44h; protein hydrolysis degree under the best condition: 25.9%. The polypeptides extracted from the sea cucumber waste liquid have high antioxidant activity, and the DPPH· scavenging activity increases with the polypeptide concentration.

In order to predict the failure probability of a complicated structure, the structural responses usually need to be estimated by a numerical analysis such as finite element method. The response surface method could be used to reduce the computational effort required for reliability analysis when the performance functions are implicit. However the conventional response surface method is time-consuming or cumbersome if the number of random variables is large. This paper presents a Legendre orthogonal neural network (LONN)-based response surface method to predict the reliability of a structure. In this method, the relationship between the random variables and structural responses is established by a LONN model. Then the LONN model is connected to a reliability method, i.e. first-order reliability methods (FORM) to predict the failure probability of the structure. Numerical example has shown that the proposed approach is applicable to structural reliability analysis involving implicit performance functions.

The artificial neural network method is adopted to solve the reliability analysis of the automobile engine. When the limit state function of structure is highly complex or with non-linearity, it is time-consuming to calculate the reliability with traditional reliability methods. The artificial neural network method is used to analyze the fatigue reliability of connecting rod of automobile engine. The working process of the connecting rod is simulated with UG software, the dynamics analysis on crank-connecting rod-piston mechanism is performed with ANSYS and ADAMS software, with the finite element analysis results, the stress information of the critical point of the connecting rod can be obtained, so the performance function of the structure can be established. The artificial neural network method is used to fit the performance function as well as its derivatives, so as to calculate the reliability of the structure.

In engineering applications the uncertainties of the structural parameters are inherent and the scatter from their nominal ideal values is in most cases unavoidable. These uncertainties play a dominant role in structural performance and the reliability-based design optimization is a useful method to assess the uncertainty influence. Compared to the basic deterministic-based optimization problem, the latter considers additional non-deterministic constraint functions and will provide the structure more safety. This paper proposed a Fourier orthogonal neural network method to the structural reliability analysis and reliability-based optimization considering uncertainties, the main aim is to minimize the weight of the structure under certain reliability constraints, and to obtain economic benefit meanwhile ensure the safety of the structure.

Boron (B) is essential for plant growth. The mechanism of B interacting with sucrose transport is not fully understood. In detached tobacco leaves treated with increasing B concentrations, the concentrations of sucrose, glucose, fructose, and starch as well as the activities of sucrose phosphate synthetase (SPS), sucrose synthetase (SS), and α-amylase were quantified. In addition, the expression levels of sucrose transporters (SUT1 and SUT4) were determined. The data presented here suggest that B promotes the sucrose concentration and transport via elevation of SPS activity, decrease of SS activity, and increase of SUT4 expression level.

Drying is a crucial step in the process of copper powder flash smelting for the direct influences on the quality of smelting. This paper proposes a unique system to match the special requirements of drying raw copper powder, such as large mass rate, small diameter dust and abrasion. On the bases of drying features and energy conservation, optimization design of drying system and equipment was also carried out. In site tests showed the satisfaction on working stability, energy thrift and quality of final product.

This paper applies super-heated steam drying technology to improve the quality of lignite. A unique experimental system was built up. In order to obtain the optimum operation conditions, the drying kinetics was measured. The temperature range of super-heated steam was from 120 to 200°C. The results showed that the drying process of super-heated steam drying of lignite can be well depicted by two stages, as a constant drying rate stage followed by a falling drying rate stage. The comparison of drying process to the hot air drying showed the superior advantages of super-heated steam drying on safety, drying capacity and energy conservation. Analysis shows the huge application potential of lignite in power plants by means of the super-heated steam drying.

Lignin was extracted from Acanthopanax senticosus remainders after pharmaceutical production process, with acetic acid-water as extracting reagent. Four factors effects, namely reaction temperature from 160°C to 220°C, reaction time from 40 min to 100 min, acetic acid concentration from 50% to 80% and solid-liquid ratio from 1:40 to 1:5, were studied and optimized by a four-level orthogonal array design (OAD) on lignin antioxidant capacity. The results indicated the reaction temperature and reaction time were significant factors among these factors. At the same lignin solution concentration, the acetic acid lignin antioxidant capacity was better than that of Kraft lignin, but much lower than that of butylated hydroxyanisole (BHA).

Stoma is surrounded by two guard cells, and regulates the contents of water and CO(2) in plant, its opening and closing was affected by various factors. Recently, dehydroascorbate was found to induce stomata closure and H(2)O(2) generation. However, the mechanism of H(2)O(2) production is not clear. DPI and imidazole inhibit the flavoprotein and the b(-type) cytochrome components of the NADPH oxidase complex. Application of DPI or imidazole with DHA together impaired stomatal closure and elevation of H(2)DCF-DA fluorescent intensity induced by DHA in guard cells. CoCl(2) and PD98059, as the blocker of calcium channel and the inhibitor of MAPKKK, both impaired stomatal closure induced by DHA. The results suggested that DHA-induced H(2)O(2) generation via activation of NADPH oxidase, and thus resulting in stomatal closure. Moreover, Ca(2+) channel and MAPK cascades were involved in stomatal closure induced by DHA.