中度嗜热微生物浸出复杂多金属铜精矿的优化(英文)

研究了中度嗜热微生物浸出复杂多金属铜矿过程中初始pH、温度、装液量、转速、原电池效应(黄铁矿比例)和矿浆浓度的影响。结果表明,初始pH为1.5的铜浸出率分别是初始pH为1.0和2.0的实验组浸出率的1.5倍和1.4倍。当温度为45°C时铜的浸出率比温度为50°C时的高出1236.8%。随着转速的升高和装液量的降低,铜的浸出率明显提高。当黄铁矿的比例增大时,铜的浸出率也逐渐提高,但是当黄铁矿比例高于20.0%后,铜浸出率不再增加。温度和pH及温度和黄铁矿比例之间存在显著的交互作用。     

有机酸改性咪唑环氧树脂固化促进剂的研究

二氰二胺作为环氧树脂的潜伏性固化剂,其固化物机械性能和介电性能优异。但由于二氰二胺与环氧树脂相溶性差,得不到均匀的组成物,且环氧树脂/二氰二胺体系的固化过程需在高于160℃的温度中进行。利用不同含量的有机酸与咪唑3位氮原子中和,改性生成的盐作为环氧树脂/二氰二胺体系固化促进剂,对该体系进行了改进,使其能够在中温(90～120℃)条件下固化。利用IR对改性产物进行了表征,并对未加促进剂的环氧树脂/双氰胺体系和以咪唑及有机酸改性咪唑为促进剂三种体系分别进行了差热分析。结果表明,有机酸改性咪唑促进剂可以使环氧树脂/二氰二胺体系的固化温度降低近50℃,并且适用期显著增加,长达141d,耐水性和耐热老化性能增加。     

Fluid‐particle drag in inertial polydisperse gas–solid suspensions

In this article, we extend the low Reynolds number fluid‐particle drag relation proposed by Yin and Sundaresan for polydisperse systems to include the effect of moderate fluid inertia. The proposed model captures the fluid‐particle drag results obtained from lattice‐Boltzmann simulations of bidisperse and ternary suspensions at particle mixture Reynolds numbers ranging from 0 ≤ Re_mix ≤ 40, over a particle volume fraction range of 0.2 ≤ ? ≤ 0.4, volume fraction ratios of 1 ≤ ?_i/?_j ≤ 3, and particle diameter ratios of 1 ≤ d_i/d_j ≤ 2.5. © 2009 American Institute of Chemical Engineers AIChE J, 2010     

Epigallocatechin Gallate Ameliorates the Effects of Prenatal Alcohol Exposure in a Fetal Alcohol Spectrum Disorder-Like Mouse Model

Fetal alcohol spectrum disorder is the main preventable cause of intellectual disability in the Western world. Although binge drinking is the most studied prenatal alcohol exposure pattern, other types of exposure, such as the Mediterranean, are common in specific geographic areas. In this study, we analyze the effects of prenatal alcohol exposure in binge and Mediterranean human drinking patterns on placenta and brain development in C57BL/6J mice. We also assess the impact of prenatal treatment with the epigallocatechin-3-gallate antioxidant in both groups. Study experimental groups for Mediterranean or binge patterns: (1) control; (2) ethanol; (3) ethanol + epigallocatechin-3-gallate. Brain and placental tissue were collected on gestational Day 19. The molecular pathways studied were fetal and placental growth, placental angiogenesis (VEGF-A, PLGF, VEGF-R), oxidative stress (Nrf2), and neurodevelopmental processes including maturation (NeuN, DCX), differentiation (GFAP) and neural plasticity (BDNF). Prenatal alcohol exposure resulted in fetal growth restriction and produced imbalances of placental angiogenic factors. Moreover, prenatal alcohol exposure increased oxidative stress and caused significant alterations in neuronal maturation and astrocyte differentiation. Epigallocatechin-3-gallate therapy ameliorated fetal growth restriction, attenuated alcohol-induced changes in placental angiogenic factors, and partially rescued neuronal nuclear antigen (NeuN), (doublecortin) DCX, and (glial fibrillary acidic protein) GFAP levels. Any alcohol consumption (Mediterranean or binge) during pregnancy may generate a fetal alcohol spectrum disorder phenotype and the consequences may be partially attenuated by a prenatal treatment with epigallocatechin-3-gallate.     

我国植物油料油脂加工技术新进展

植物油料油脂加工的主要内容包括油脂及蛋白的初加工和深加工技术、综合利用技术、工程装备技术及品质控制技术等,概述了我国植物油料油脂加工技术新进展。我国已初步建立起基于营养和安全为评价标准的食用植物油精准适度加工体系;突破了零反式脂肪酸专用油脂生产技术,能满足各种食品加工场景需求;功能油脂制备技术成果渐次落地,推动产业进入蓬勃发展期,多款结构脂产品进入量产,跨国公司垄断局面得以改变;新油源开发方兴未艾;植物蛋白结构功效关系基础研究促进了植物基产品开发;油料油脂综合利用规模扩大;食用油安全防控技术、绿色储油技术研究不断深入;大型浸出器和浓缩蛋白制取装备的设计和制造水平达到国际先进水平;智能化工厂建设支撑我国油料油脂加工各项经济技术指标处于世界领先地位。     

中度嗜热菌浸出黄铁矿过程中矿物表面硫的化学形态

利用扫描电镜(SEM)、X射线衍射(XRD)和硫的K边X射线吸收近边结构光谱(XANES)等分析手段研究了中度嗜热菌(Sulfobacillus thermosulfidooxidans)浸出黄铁矿过程及矿物表面硫的化学形态.结果表明:中度嗜热菌明显促进了黄铁矿的溶出,24 d浸出液中总铁的质量浓度达到5.3 g·L^-1.经24 d细菌处理后,矿物表面形貌变化明显,出现良好结晶状态的晶体.浸出过程中累积在黄铁矿表面的主要成分是黄钾铁矾.矿物表面硫的形态组分主要为黄铁矿和黄钾铁矾,其质量分数分别为34.8%和65.2%.     

Limiting distribution of the score statistic under moderate deviation from a unit root in MA(1)

This article derives an asymptotic distribution of Tanaka's score statistic under moderate deviation from a unit root in a moving average model of order one [MA(1)]. The limiting distribution is classified into three types depending on the order of deviation. In the fastest case, the convergence order of the asymptotic distribution continuously changes from the invertible process to the unit root one. In the slowest case, the limiting distribution coincides with one in the invertible process in the distribution sense. This implies that they share a common asymptotic property. The limiting distribution in the intermediate case has the boundary property between the fastest case and the slowest one.     

适度垄断下建筑业技术创新效用模型

中国建筑业技术创新缺乏生机，通过适度垄断来激励建筑企业进行技术创新不失为一种较优选择。文中先假设建筑行业内，超级大企业可以全面地参与行业竞争，运用企业产出模型证明了建筑业适度垄断企业数目确定性问题。其次，以国有大型施工企业为主体，进一步假设在适度垄断下建筑企业连续增加R＆D费用可以提高生产力，并且在建筑企业的生产阶段均有研发（R＆D）投资，运用LaGrange函数建立了适度规模下建筑业技术创新效用模型，模型解揭示我国建筑业企业技术创新效用不明显，同期的建筑业技术创新障碍性因素调查研究和1991-2004建筑业的增长率曲线支持此结论。     

Modifications of starch by electric field based techniques

BackgroundNative starches have limited applications and are commonly modified for desired properties. There has been increasing demand for physically and non-chemically modified starches from the market as consumers prefer “natural and healthy” food products. Among various physical means, electric field based techniques have been gaining a research focus for starch modifications during the last few years. Another trend is to produce modified starches using cleaner process. Electric fields of certain conditions can facilitate the “cleaner production” of food and industrial ingredients.Scope and approachThis mini-review summarises the modifications of starches from different botanical sources by the electric field based techniques. The techniques are based on pulsed electric field, induced electric field, moderate electric field, and ohmic heating. Physicochemical properties, granular and molecular structures, applications of starch as affected by the electric field based modifications are reviewed. Structure-function relationships of starch as affected by the electric fields are discussed. Impact of electric fields on food systems rich in starch (e.g., flour) is also reviewed. Research gaps to better utilize these techniques for starch modifications are suggested.Key findings and conclusionsDifferent electric field based methods greatly modify the starch physicochemical properties to different extents. Factors affecting the outcomes of the modifications include the starch type and concentrations, electrical conductivity, and electric field type, strength, and duration. Starch modification processes such as hydrolysis and substitutions can be efficiently optimized by applying electric fields. The functionalities of food systems rich in starch can also be modified by these techniques. It becomes evident that electric field based techniques have potential to be used in starch modifications to create a range of functionalities and to help meet the ever-rising market of clean label ingredients.     

我国食用植物油市场的挑战及机遇

我国食用油产业发展迅速,但仍然面临各种挑战。通过对我国食用油市场的发展现状、加工过程中危害物质深度分析欠缺、小品种油料资源的全面化市场调研欠深入、植物油营养评价和特殊人群的专用食用调和油研究开发不足等方面进行分析,提出我国食用植物油市场面临机遇与前景展望,推广油脂精准适度加工新模式,系统开发我国油料资源,研究食用油营养学价值,开发特殊人群的专用食用调和油,为推动油脂加工业的高质量发展提供参考建议。