Rehydration kinetics at 5 and 15 °C of dry salted meat

The surface of meat products during intermittent drying is successively subjected to dehydration and rehydration processes. The aim of this paper was to study the rehydration kinetics at two temperatures (5 and 15 °C) of salted ground pork, (2% or 4% NaCl) dried to different water contents, (10%, 20% and 35%) using Peleg and Weibull’s models. Surface structure of dried samples was analyzed with electron microscopy and related to rehydration kinetics. The equilibrium water content decreased with temperature and increased with NaCl, but was not affected by the initial water content. The rehydration rate at the beginning decreased with water content and was significantly higher at 5 °C than at 15 °C, but it was not significantly affected by NaCl content. However, the equilibrium water decreased with temperature and tended to increase with NaCl content, but was not affected by the initial water content. High level of dehydration resulted in a more damaged and porous meat matrix. This microstructure may contribute to accelerating the rehydration process.     

细菌纤维素合成菌株发酵条件的考察

菌株QAX0 2 1 9# 进行液态发酵可产生不溶性的凝胶膜 ,通过纤维素酶水解等实验确定其发酵产物为纤维素 ,同时研究了乙醇、溶氧含量、培养方式以及接种量对菌体合成纤维素的影响。结果为 :以 8%接种量 ,在发酵培养基中添加一定量的乙醇 ,可显著提高纤维素产量     

In vitro inhibition of postharvest pathogens of fruit and control of gray mold of strawberry and green mold of citrus by aureobasidin A

Aureobasidin A (AbA), an antifungal cyclic depsipeptide antibiotic produced by Aureobasidium pullulans R106, has previously been shown to be effective against a wide range of fungi and protozoa. Here we report the inhibitory effects of AbA on spore germination, germ tuber elongation and hyphal growth of five pathogenic fungi including Penicillium digitatum, P. italicum, P. expansum, Botrytis cinerea and Monilinia fructicola, which are major pathogens causing postharvest diseases of a variety of fruits. AbA inhibited five pathogenic fungi by reducing conidial germination rates, delaying conidial germination initiation, restricting elongation of germ tuber and mycelium, as well as inducing abnormal alternations of morphology of germ tubes and hyphae of these fungi. The sensitivity of these fungi to AbA was pathogen species-dependent. P. digitatum was the most sensitive and M. fructicola the least. Importantly, AbA at 50 microg/ml was effective in controlling the citrus green mold and in reducing the strawberry gray mold incidence and severity, caused by P. digitatum and B. cinerea, respectively, after artificial inoculation. AbA and/or its analogs, therefore, hold promise as relatively safe and promising fungicide candidates to control postharvest decays of fruits, because AbA targets the inositol phosphorylceramide (IPC) synthase, an enzyme essential for fungi but absent from mammals.     

多磺酸盐基液复配体系对超稠油的室内降粘研究

磺酸盐作为降粘剂具有抗温、抗盐的优良特性。筛选合适的降粘剂和磺酸盐基液进行复配是对磺酸盐下游产品的回收利用,具有变废为宝的实用价值,为磺酸盐基液的开发利用开辟了新的途径。测定降粘率的条件经探究确定为:油/水质量比为7∶3,原油乳化时间为1小时,搅拌速率为200 r/s,搅拌时间为2 min。筛选出的表活剂AES和AEO在0.05%和0.5%时与磺酸盐基液达到最佳复配效果,降粘率达到99%左右。经室内驱油物理模拟实验得到最佳的降粘剂配方:磺酸盐(10%)+AES(0.04%)混合驱提高采收率为5.23%。     

浮法玻璃配合料粒化的研究

通过粒化实验确定了具有较好粒化性能的工艺参数,通过高温熔制实验得出熔化粒化后的配合料可以达到节能的目的.     

大、小飞扬草中锌铁锰微量元素的测定

目的:测定大、小飞扬草中Zn、Fe、Mn三种微量元素的含量。方法:硝酸和高氯酸(4+1)分解样品,火焰原子吸收光谱法(FAAS)测定。结果:大、小飞扬草中三种微量元素存在差异,其中大飞扬草中元素含量大小为:Fe>Mn>Zn,小飞扬草中上述元素含量为:Fe>Zn>Mn。回收率在97.0%~106.0%之间,RSD<2.1%。结论:大、小飞扬草中三种微量元素含量的差异测定可为进一步研究其药效与有关微量元素关系提供一定参考。     

掺钕YAG陶瓷的显微结构和掺杂分析

利用X射线衍射（XRD）、吸收光谱、数字金相显微镜、扫描电镜（SEM）和能谱（EDS）分析了真空烧结法制备的掺钕YAG陶瓷的显微结构和掺杂情况。结果表明：制备的Nd：YAG激光陶瓷物相单纯,晶粒大小分布均匀,大部分晶粒尺寸在5—8μm之间,但晶界残留气孔,透明性还有待提高,与原料粉体、烧结制度有关。同时,掺杂离子Nd^3＋在晶界和晶粒内部均匀分布。     

流速对磁场阻垢效果的影响

利用双道的实时监测系统,通过监测碳酸钙过饱和溶液中的pH和Ca2 浓度在析晶过程中的变化,系统的研究了不同流速下磁场的阻垢效果.准确、可重复的试验数据表明,磁场对碳酸钙过饱和溶液有阻垢效果,并且不同流速下磁场的阻垢效果不同.同时试验结果还表明在磁处理时间恒定的条件下,在0～6 m/s的流速范围内,溶液通过磁场的流速越高磁处理的阻垢效果越强.     

新型层状陶瓷Ti3SiC2的研究进展

新型层状陶瓷Ti3SiC2兼有金属和陶瓷的许多优良性能,具有高的热导率和电导率,易加工,同时具有良好的抗热震性、抗氧化性和高温稳定性.本文从层状陶瓷Ti3SiC2制备方法、结构和性能等方面进行综述,并对其应用前景进行展望.