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To develop a biscuit product with high dietary fiber content and improve the comprehensive utilization rate of bamboo shoots, Chimonobambusa quadrangularis shoot powder (CQSP) was added to biscuits. Inspected by the effect of CQSP addition, butter addition, sugar addition, baking temperature and baking time on the quality of biscuits, using chroma value, texture properties and sensory evaluation as the index, studied by single factor experiment to optimize the Chimonobambusa quadrangularis shoot biscuits craft formula. The results showed that with the increase of CQSP addition, the a* and b * of biscuits increased. The L* did not change significantly when the content of CQSP was added from 0% to 3%, the brightness of biscuits decreased significantly (P>0.05) when the content of CQSP was added from 4% to 5%, and the hardness, crispness and chewiness of biscuits increased gradually. The hardness, crispness and chewiness of the biscuits decreased with the increase of butter content. The biscuit quality was better, when the content of butter added was 24%. The hardness of the biscuit increased with the increase of sugar content. When the sugar content was 13%~15%, the biscuit hardness was the best. The L* of biscuits gradually decreases with the increase of baking temperature. When the baking temperature was 160~180 ℃, the biscuits become dark obviously. With the increase of baking time, the a* and b * of biscuits increased, the L* gradually decreased, and the hardness, crispness and chewiness of biscuits increased gradually. After single factor optimization, the best formula of CQSP crisp biscuit was CQSP 3%, butter 24%, sugar 13%, baking at 150 ℃ for 25 minutes. Under the technological conditions, the L* of was 71.1, the a* was 2.05, the b* was 27.43, the hardness was 2466.16 g, the crispness was 2050.02 g, the chewiness was 541.29, the sensory score could reach 83.1. The results can provide a theoretical reference for high value utilization of by-products of bamboo shoot processing.

To investigate the optimal extraction process, component composition and antioxidant activity of bound polyphenols in bamboo shoots dietary fiber (BSDF), the extraction time, extraction temperature, alkali concentration and liquid-to-material ratio on the extraction yield were researched in this paper. Thereafter, the extraction process of bound polyphenols in BSDF was optimized by Box-Behnken response surface experiment based on single-factor experiments. The components of bound polyphenols were preliminarily identified and the antioxidant activity such as ABTS cation radicals, DPPH radicals, superoxide anion radicals and hydroxyl radicals were investigated. The results showed that alkali concentration of 9 mol/L, extraction temperature of 40 °C, extraction time of 4 h and liquid-to-material ratio of 20:1 mL/g were the optimal condition. Under this condition, the predicted extraction amount of bound polyphenols in BSDF was 27.95 mg GAE/g BSDF while the actual extraction amount was 26.68±0.73 mg GAE/g BSDF, with a prediction accuracy of 95.46%. There were 12 polyphenolic components including sinapic acid, gallic acid, ferulic acid, and coumaric acid were preliminarily identified by ultra performance liquid chromatography-triple quadrupole mass spectrometer. The free radical scavenging rate of polyphenols extract initially increased and then gradually stabilized with the increase of mass concentration. The scavenging rates of ABTS cation radical, superoxide anion radical and hydroxyl radical reached 73.24%, 59.92% and 51.41% with mass concentration of 3.0 mg/mL, respectively. The scavenging rate of DPPH radical reached 76.79% when the concentration was 1.25 mg/mL. The scavenging rate of each group was less than that of ascorbic acid solution of the same mass concentration. The results can provide theoretical reference for the development and utilization of polyphenols in BSDF.

In order to improve the vibration and noise of automobile gearbox， by using the Romax， a dynamics model of the transmission drive system is established， and the dynamic bearing force during the operation of the gearbox is obtained by simulation. The modal analysis is performed on the built finite element box model to learn the box relatively weak areas. The dynamic force of the bearing simulation is used as the excitation of the shell vibration response analysis to analyze the shell vibration characteristics， the shell vibration acceleration is used as the boundary condition， and based on the shell acoustic boundary element model， the modal acoustics transfer method is used to calculate the radiated noise from the sound field outside the casing. By analyzing the modal participation factor and the modal acoustic contribution， the modals which contribute more to vibration noise are determined， and optimization is performed in the corresponding modal vibration sensitive place. The results show that the vibration noise of the optimized gearbox decreases and the radiated noise decreases by 1.4 dB.

In this study, different mass concentrations (0%, 1%, 2%, 3%, and 4%, based on starch mass) of tamarind seed polysaccharides (TSP) were added to endow potato starch (PS) bread with gluten-like properties in order to improve the processing performance and texture quality of gluten-free bread. The results indicated that adding TSP increased the peak viscosity of PS, improve its viscoelasticity, and endow it with gluten-like network structural characteristics. With increasing TSP concentration, the baking loss rate of gluten-free bread significantly decreased from 26.01% to 20.36%, and the specific volume increased from 1.27 mL/g to a maximum value of 3.19 mL/g. The addition of TSP significantly improved the texture characteristics of bread, as evidenced by a reduction in its hardness, cohesiveness, chewiness and resilience, resulting in a softer texture. Adding TSP delayed the staling of bread, thereby extending the shelf life. Principal component analysis (PCA) showed strong correlations between bread quality and baking performance and gelatinization characteristics of PS. This study has expanded the application of TSP in food field and provides new ideas and a theoretical basis for the development of gluten-free starch products.

传统塑性脂肪带来健康问题，液态油固化成为构建零反式、低饱和脂肪酸塑性脂肪替代品的新策略。蛋白质是优质的食品营养组分，是来源广泛的可再生资源，具有独特的界面特性。为扩大蛋白资源的应用范围及促进功能性油脂的开发，对蛋白质的结构化及蛋白基乳液模板法构建油凝胶（结构化油脂）研究进展进行了综述，同时介绍了蛋白基乳液模板法构建的油凝胶的应用。蛋白质在一定条件下可作为凝胶剂固化液态油；蛋白基乳液模板法构建油凝胶具有安全性高、对环境污染小等优点。采用蛋白基乳液模板法构建的油凝胶可应用于替代传统塑性脂肪、荷载生物活性成分方面。 The traditional plastic fats cause health problem, and solidification of liquid oil is considered as a new strategy to obtain plastic fat with zero-trans and low-saturated fatty acids. As a high quality nutrition component of food, protein is a renewable resource with a wide range of sources, and it has unique interface properties. To expanding protein applications and development of functional fats, the research progress of structuring protein and constructing oleogels by protein based emulsion template method was reviewed. The application of oleogels constructed by protein based emulsion template method was also summarized. Under certain conditions, protein could be used as a gelling agent to solidify liquid oil to prepare oleogels. Constructing oleogels by protein based emulsion template method has the advantages of high safety and low environmental pollution. The oleogels constructed by protein based emulsion template method could be used to replace traditional plastic fats and load bioactive ingredients.

Coal spontaneous combustion fire is one of the major disasters in the process of mine production, which threatens the safety of mine production. Spontaneous combustion of coal is a complex oxidation process, which has to go through different oxidation stages, so it is necessary to set up corresponding indexes to judge different stages of coal-oxygen reaction. The rule of index gas changing with temperature in the process of spontaneous combustion and oxidation of long flame coal was analyzed by temperature programmed-gas chromatography (TG-GC). According to the experimental data of temperature oxidation, spontaneous combustion of coal can be divided into four stages. Using φ(CO)/φ(CO2) and the third fire coefficient R3 as auxiliary indexes, the stages of coal-oxygen reaction were divided. At the same time, the law of δ18O(oxygen isotope) in gas products changing with temperature is obtained by measuring the oxygen isotope abundance in CO and CO2 of low volume fraction, and the coal spontaneous combustion is divided into four stages according to the law of δ18O.