利用CSTR生物制氢系统厌氧发酵的研究现状

生物制氢技术在开发能源方面具有重要的现实地位,连续流搅拌槽式反应系统（CSTR）采用机械搅拌,传质效率高,可有效提高产氢效率,同时此设备技术要求较为简单,能大幅降低生物制氢的成本,易于实现氢气的工业化生产.本文阐述了连续流搅拌槽式反应器（CSTR）生物制氢系统的研究进展,着重剖析了CSTR生物制氢系统的影响因素、底物范围和相关的技术研究,并对其发展和实际应用进行了简要论述.     

Ranges of Expedient Use of Extrahigh-Voltage-Class AC and DC Transmission Lines in the United Energy System of Russia

Generalized characteristics of 500 – 2000-km transmission lines are used to define the ranges of expedient use of ac and dc transmission for the Unified Energy System of Russia with allowance for the reliability factor and today's cost parameters.     

Trace metal stabilisation in a shooting range soil: mobility and phytotoxicity

Due to impact and abrasion of projectiles firing berms of shooting ranges frequently exhibit increased levels of bullet-borne contaminants. Stabilisation of backstop soils may be a promising pre- and post-use treatment to minimise leaching and bioavailability. This study focused on mobility and phytotoxicity of antimony, copper, and lead in stabilised berm material compared to an untreated control. Ferric (goethite, deferrisation sludge) and phosphatic amendments (diammonium phosphate, calcium dihydrogen phosphate) were used. Batch and column experiments demonstrated effective stabilisation of the contaminants by ferric amendments. Sequential extractions showed an increase of contaminant fractions associated with iron (hydr)oxides. Stabilisation was accompanied by a detoxification of seepage water compared to the control soil as shown by Duckweed growth inhibition. Contrasting the ferric additives, phosphatic amendments effectively stabilised lead but mobilised copper and antimony possibly due to a competitive displacement process. Thereby, benefits of lead stabilisation were completely overridden; this was underlined by increased phytotoxicity relative to the untreated soil. Overall, understanding stabilised soil as a multicomponent system is a prerequisite for the choice of appropriate amendments. This requires the synopsis of results from complementary test methods and a screening for a wide range of substances.     

On computation of stabilizing loop gain and delay ranges for bi-proper delay systems

A graphical method for exactly computing the stabilizing loop gain and delay ranges was proposed [Le BN, Wang Q-G, Lee T-H. Development of D-decomposition method for computing stabilizing gain ranges for general delay systems. J Process Control 2012] for a strictly proper process by determining the boundary functions which may change system׳s stability. A bi-proper process is rare but causes great complications for the method, due to the new phenomena that do not exist for a strictly proper process, such as a non-zero gain at infinity frequency, which may cause infinite intersections of boundary functions within a finite delay range. This paper addresses such a kind of processes and develops a general method that can produce the exact and complete set of the loop gain and delay for closed-loop stabilization, which is hard to find with analytical methods.     

漏电与短路保护范围交叉

论述了剩余电流动作保护器与短路保护电器保护范围交叉的概念,必要性和判断方法,为使两种保护具有足够的交叉范围,还提出了在设计中应注意的问题。     

生鲜肉贮藏温度术语浅析

肉类工业是第一大食品产业和国民经济支柱产业。生鲜肉占肉与肉制品生产与消费量的80%,而贮藏是生鲜肉消费最重要的环节,低温贮藏是生鲜肉贮藏的较优方法之一。根据贮藏温度不同,生鲜肉的贮藏可分为冷藏、冰温、超冰温、微冻、冻结/冻藏等,但一直以来概念混淆不清、温度范围模糊,影响了肉类生产和行业的规范运行。本文综述低温贮藏中冷藏、冰温、超冰温、微冻、冻结/冻藏的术语,旨在明晰其贮藏温度范围,为后续研究和生产提供参考。     

改进卡尔曼滤波在北斗伪距定位中的研究

针对最小二乘迭代法定位精度不高和卡尔曼滤波迭代收敛次数较多并对初始位置过于敏感的缺点,采用最小二乘迭代法和改进的卡尔曼滤波相结合的模型方法,该算法先用最小二乘迭代法对初始位置进行定位,再用改进的卡尔曼法进行滤波,仿真结果表明,该算法与最小二乘迭代法、卡尔曼滤波法、最小二乘和卡尔曼滤波结合等现有算法相比,其迭代5次达到收敛,迭代次数最少,且定位精度提高了60%。该算法可在北斗伪距定位上进行应用,可用于导航定位、也可用于网络RTK初始位置的定位。