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1.
Lobster krill (Munida genus) represents an under‐valued crustacean frequently caught on European fishing banks. In this work, its sensory, microbiological and biochemical qualities were evaluated during chilled storage. Additionally, the effects of a prestorage antimelanosic treatment consisting of soaking in sodium metabisulphite (SMB) solutions at two different concentrations (0.25% and 0.75%) were also studied. SMB prestorage treatment provided lobster specimens that still exhibited acceptable sensory quality after 10 days of storage, while control specimens were unacceptable at that time. SMB treatment also resulted in a significant (P < 0.05) inhibition of microbial growth, mainly of Enterobacteriaceae, psychrotrophes and proteolytic bacteria. Low lipid oxidation levels were observed for all batches; however, a significantly higher (P < 0.05) retention of polyunsaturated fatty acids was found in SMB‐treated lobster, especially in the 0.75% SMB batch. The results presented here open the way to the potential commercialisation of currently under‐utilised lobster krill as a chilled product.  相似文献   
2.
This work investigates the effect of the addition of small amounts of Ru (0.5‐1 wt%) to carbon supported Co (10 wt%) catalysts towards both NaBH4 and NH3BH3 hydrolysis for H2 production. In the sodium borohydride hydrolysis, the activity of Ru‐Co/carbon catalysts was sensibly higher than the sum of the activities of corresponding monometallic samples, whereas for the ammonia borane hydrolysis, the positive effect of Ru‐Co systems with regard to catalytic activity was less evident. The performances of Ru‐Co bimetallic catalysts correlated with the occurrence of an interaction between Ru and Co species resulting in the formation of smaller ruthenium and cobalt oxide particles with a more homogeneous dispersion on the carbon support. It was proposed that Ru°, formed during the reduction step of the Ru‐Co catalysts, favors the H2 activation, thus enhancing the reduction degree of the cobalt precursor and the number of Co nucleation centers. A subsequent reduction of cobalt and ruthenium species also occurs in the hydride reaction medium, and therefore the state of the catalyst before the catalytic experiment determines the state of the active phase formed in situ. The different relative reactivity of the Ru and Co active species towards the two investigated reactions accounted for the different behavior towards NaBH4 and NH3BH3 hydrolysis.  相似文献   
3.
测算了由二(2-乙基己基)磷酸钠,金属盐(CoSO4,NiSO4,ZnSO4,MgCl2或Cr(NO3)3)水溶液,正辛醇和正辛烷组成的微乳液中正辛醇从连续油相到界面的ΔGo→i^o和水的极限增容量φ'H2O。用金属萃取络合物反胶束的形成及其亲油性解释了金属离子对φ'H2O和ΔGo→i^o的影响。  相似文献   
4.
电位滴定法快速测定洗衣粉中的聚磷酸盐含量   总被引:1,自引:0,他引:1  
他德洪 《贵州化工》2002,27(3):26-27
用强酸分解洗衣粉中的聚磷酸盐,以电位滴定法间接测定其中的聚磷酸盐含量。该法简便,快速,结果可靠。  相似文献   
5.
The objective of this study was to evaluate the effectiveness of sodium benzoate as an inhibitor to slow down or prevent atmospheric corrosion/discoloration of the local mild steel during storage in the Arabian Gulf region. Test specimens were prepared from locally produced reinforcing steel products. The inhibitor solution was applied on steel specimens at a concentration of 100 mM for 1 day at room temperature. Wooden exposure racks were used to hold as-received and inhibitor-treated specimens during atmospheric exposure for different periods. Corrosion was evaluated through weight loss determination and electrochemical technique. As expected, the Arabian Gulf atmosphere was corrosive on the as-received local mild steel. On the other hand, treatment of steel with sodium benzoate lowered its corrosion rate during initial days of its exposure to atmosphere. However, atmospheric corrosion inhibition performance of sodium benzoate deteriorated with exposure time after 30 or more days of atmospheric exposure, and the corrosion rates of sodium benzoate-treated specimens reached that of the unprotected specimens at the end of 90 days of atmospheric exposure.  相似文献   
6.
利用十二酰胺丙基二甲胺和氯乙醇反应 ,合成了十二酰胺丙基二甲基羟乙基氯化铵 (DDHA)阳离子表面活性剂 ,将其与十二烷基硫酸钠 (SDS)以不同摩尔比进行混合 ,测定了混合系统的表面张力 ,计算了单一系统和混合系统的饱和吸附量、分子最小截面积 ,表面层和胶束中 DDHA的摩尔分率及分子间相互作用参数 ,目视观察了混合系统的浑浊情况。结果表明 :在降低γcmc和 cmc方面 ,DDHA SDS混合系统有协同效应 ,表面层和胶束的组成与二组分配比有关 ,但是非对称的 ,等物质的量混合物中 ,DDHA在胶束和表面层中具有较大的摩尔分数。DDHA与 SDS在实验测定的各混合系统中都不出现混浊  相似文献   
7.
采用差示扫描量热仪研究了5种具有不同取代基的苯甲酸钠盐作为结晶成核剂对聚对苯二甲酸乙二醇酯(HET)结晶和熔融行为的影响,并同滑石粉进行了对比。结果表明,成核剂的加入能明显改变PET的结晶和熔融行为。苯甲酸钠、对苯二甲酸甲酯单羧酸钠和对羟基苯甲酸钠提高既汀的熔融结晶温度(Tc)分别达22.93、21.7和19.37℃,但使PET降解严重;对苯酚钠甲酸钠能够提高Tc达17.75℃且对PET相对分子质量影响很小;对苯二甲酸二钠成核作用最差。低于滑石粉。此外,成核剂的成核能力越强,PET双熔融峰中的低温峰顶温度就越高。  相似文献   
8.
对KCl与NaCl在低盐固态酱油发酵中的应用进行了比较研究。结果表明:用KCl代替NaCl,KCl的浓度要高于NaCl才能抑制发酵期间杂茵的污染,且使用KCl的发酵效果比NaCl要好。  相似文献   
9.
NaAlO_2-Al_2(SO_4)_3法制备拟薄水铝石成胶机理的研究   总被引:2,自引:0,他引:2  
研究了拟薄水铝石和三水氧化铝的生成机理。考察了成胶pH、成胶温度对生成物类型的影响,在此基础上确定了NaAlO2溶液和Al2(SO4)3溶液成胶过程中完全中和时的临界体积比Ψ/Ψ0,在成胶过程中,当Ψ/Ψ0≤1时,NaAlO2溶液与Al2(SO4)3溶液发生中和反应生成拟薄水铝石和/或碱式硫酸铝;当Ψ/Ψ0>1时,过量的NaAlO2溶液发生自发水解反应,生成三水氧化铝。  相似文献   
10.
Intact and ovariectomized oxytocin (OT)-deficient (OT-/-) and wild-type (OT+/+) mice were tested for consumption of 0.5 M NaCl solution or tap water in a 2-bottle choice test. During 3 days of acclimation, voluntary ingestion of NaCl was equal between genotypes. After overnight fluid deprivation, intact OT-/- mice ingested 2 times more NaCl solution than OT+/+ mice in the 6th hr, but not the 1 st hr, after reintroduction of fluid. Ovariectomized mice consumed less than intact mice after overnight fluid deprivation. When a 0.2 M NaCl solution was administered for 6 days in ovariectomized mice, OT-/- mice voluntarily consumed greater amounts than OT+/+ mice. After overnight fluid deprivation, consumption by OT-/- mice was 3 times that of OT+/+ mice at 1 hr and 2-fold greater after 6 hr. Enhanced intake of NaCl-containing solutions in female OT-/- mice suggests that central OT may be an important inhibitor of sodium consumption. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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