关于 HCSC6 型环锤式碎煤机调节间隙的计算及应用

论述ＨＣＳＣ６型环锤式碎煤机筛板间隙的调节原理和理论计算方法,并使之运用于实际,使碎煤机筛板间隙的调节快速、准确,为环锤式碎煤机在理想工况下运行创造必要的条件。     

Thermal explosion hazards on 18650 lithium ion batteries with a VSP2 adiabatic calorimeter

Thermal abuse behaviors relating to adiabatic runaway reactions in commercial 18650 lithium ion batteries (LiCoO₂) are being studied in an adiabatic calorimeter, vent sizing package 2 (VSP2). We select four worldwide battery producers, Sony, Sanyo, Samsung and LG, and tested their Li-ion batteries, which have LiCoO₂ cathodes, to determine their thermal instabilities and adiabatic runaway features. The charged (4.2 V) and uncharged (3.7 V) 18650 Li-ion batteries are tested using a VSP2 with a customized stainless steel test can to evaluate their thermal hazard characteristics, such as the initial exothermic temperature (T₀), the self-heating rate (dT/dt), the pressure rise rate (dP/dt), the pressure-temperature profiles and the maximum temperature (T_max) and pressure (P_max). The T_max and P_max of the charged Li-ion battery during the runaway reaction reach 903.0 °C and 1565.9 psig (pound-force per square inch gauge), respectively. This result leads to a thermal explosion, and the heat of reaction is 26.2 kJ. The thermokinetic parameters of the reaction of LiCoO₂ batteries are also determined using the Arrhenius model. The thermal reaction mechanism of the Li-ion battery (pack) proved to be an important safety concern for energy storage. Additionally, use of the VSP2 to classify the self-reactive ratings of the various Li-ion batteries demonstrates a new application of the adiabatic calorimetric methodology.     

Effects of equivalence ratio,thickness of rupture membrane and vent area on vented hydrogen–air deflagrations in an end-vented duct with an obstacle

Experiments were conducted in an obstructed 3-m-long duct to investigate the effects of equivalence ratio, thickness of rupture membrane, and vent area on vented hydrogen–air deflagrations. Shockwave-induced pressure peaks were observed inside and outside the duct in some tests. In the tests with one end of the duct totally opened, the location at which the overall maximum internal overpressure is achieved depends on the thickness of the rupture membrane for a given equivalence ratio; however, it is independent of equivalence ratio for a given thickness of rupture membrane. The pressure peak resulting from an external explosion always dominates the pressure–time histories 1.5 m downstream of the duct exit. The maximum internal and external overpressures first increase and then decrease as the equivalence ratio increases from 0.26 to 3.57, unexpectedly; none of these increase monotonically with an increase in the thickness of the rupture membrane. Two explosion venting regimes, namely sonic and subsonic, are observed. During sonic venting, the maximum internal overpressure increases exponentially with a decrease in vent area; it is nearly independent of the vent area during subsonic venting when the vent area is larger than approximately 19% of the cross-sectional area of the duct.     

对双螺杆挤出机生产硬PVC制品的探讨

文章在研究了双螺杆挤出机各段中物态变化及作用的基础上,分析了目前硬PVC制品生产中使用双螺杆挤出机的一些问题,如平行双螺杆挤出机能否用于生产异型材、是否一定要使用定量给料器、挤出机排气口冒料的工艺控制及螺杆设计等问题。     

肋脉羊肚菌液体培养条件的研究

对肋脉羊肚菌进行液体摇瓶培养,以菌丝干重、胞内多糖产量及其得率为筛选指标,得到最适合肋脉羊肚菌生长的培养基条件为可溶性淀粉浓度2%、豆粕粉浓度1%、MgSO4·7H2O 0.1%、KH2PO4 0.05%、初始pH 7.5、培养温度28℃.培养8d后菌丝干重达16.94g/L,胞内多糖量达0.984g/L.