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101.
金针菇速冻工艺   总被引:1,自引:0,他引:1  
提出了速冻金针菇的加工工艺流程,并对金针菇原料的护色方法进行了分析研究。速冻可以最好地保持金针菇的原有新鲜状态、色泽风味和营养成分,因此倍受国内外消费的青睐。  相似文献   
102.
S-J. Park    H-W. Park    J. Park 《Journal of food science》2003,68(3):976-981
The inactivation kinetics of food poisoning microorganisms using a combined treatment of carbon dioxide (CO2) with high hydrostatic pressure (HHP) was investigated. Staphylococcus aureus, Fusarium oxysporum, and Fusarium sporotrichioides were totally inactivated by a combined treatment of carbonation and HHP at 500 MPa. Bacillus subtilis, a spore forming bacteria, were not completely inactivated after the combined treatment. The microorganisms treated by carbonation and HHP were exponentially reduced in a pressure range and the Dp ‐value, the Zp‐value, and the activation volume were determined. UV absorbing materials leaked from injured cells. Morphological changes of the cells were observed by scanning and transmission electron microscopy.  相似文献   
103.
重金属中毒对裂化催化剂反应性能影响的关联   总被引:1,自引:0,他引:1  
利用催化裂化反应试验数据,经参数估计建立了转化率、焦炭产率和氢气产率与催化剂重金属含量的关联模型。统计检验结果表明,所建3个模型均具有较高的计算精度。研究结果表明,与钒相比,镍对焦炭产率和氢气产率影响较大,对转化率影响较小;随着催化剂重金属沉积量的提高,氢气产率不断提高,焦炭产率提高幅度呈先较大后较小的变化规律,而反应转化率呈先有所提高然后降低的变化规律。  相似文献   
104.
The poisoning of a commercial Pd/Al2O3 catalyst by pyridine and thiophene during the selective hydrogenation of styrene to ethylbenzene was studied. It was found that the Pd electronic state is the main factor controlling the interaction between the metal and the poisons. Pyridine added to the non-poisoned feed in a pulse produces a modification in the Pd electronic state and a decrease in conversion, but, within certain limits, inhibits the adsorption of more pyridine or thiophene molecules.  相似文献   
105.
The oxygen storage capacity of a 56,000 mile aged warmup and underfloor converter system was characterized as a function of axial location along the converters and compared with fresh samples having the same formulation. Measurements of oxygen storage were made using a titration technique and at conditions expected to be commonly encountered during OBD-II diagnosis of catalyst performance. Vehicle aging resulted in a dramatic loss of oxygen storage in the warmup converter presumably due to the severe thermal sintering, but the significant amount of phosphorus (P) and zinc (Zn) poison accumulation on this converter was found to impact oxygen storage minimally. This is in contrast to the measured impact of P and Zn deposition on warmed-up hydrocarbon conversion, which was found to be significant relative to the impact of thermal sintering. The underfloor converter was found to have retained nearly all of its original oxygen storage after vehicle aging, consistent with operation of this converter at moderate temperatures which do no result in severe thermal sintering of the noble metals and the ceria.

The impact of sulfur on the oxygen storage of both warmup and underfloor converter sections was dramatic. Sections in the forward part of the warmup converter and in the front brick of the underfloor converter had relatively modest oxygen storage capacity which was almost completely blocked as the sulfur concentration reached 75–150 ppm (equivalent in gasoline). Other sections such as the rear of the warmup converter and the rear monolith of the underfloor converter had more oxygen storage capacity, which was significantly decreased as the sulfur concentration reached 150 ppm equivalent in fuel, and was approached complete loss near 500 ppm sulfur equivalent in fuel.  相似文献   

106.
Cap color was characterized on a wide range of Agaricus bisporus strains. L, a and b tristimulus coordinates were tested by linear model analysis to determine color information related to each parameter. One model was retained: log(L/(100-L)) =α* H +β. Visual cap color variation was continuous and well described by log(L/(100-L)) or H parameters. In the wild, the range of color varied from white to dark brown which would enable mushroom breeding for cap color adapted to the market.  相似文献   
107.
The paper reports the results of on-site regeneration catalytic bed of the natural gas reformer in a 5 kW PEM fuel cell system. The Ni catalyst previously poisoned by sulphur from the available natural gas, could be re-activated by injection of pure water steam, following the method developed for industrial reformers using the same metal catalyst: this method was shown to be perfectly efficient, provided no natural gas was fed during the operation. Results of the tests conducted are presented and discussed in relation to published data on S-sorption on Ni surfaces.  相似文献   
108.
Maria Ziolek   《Catalysis Today》2003,78(1-4):47-64
This review article is devoted to the materials containing niobium, which have been discovered or developed in the past few years and exhibit the potential application in heterogeneous catalysis. Niobium oxides and mixed oxides as well as sulfides, nitrides (oxynitrides), carbides (oxycarbides), and phosphates are considered. Among the catalytic processes in which Nb-containing materials were tested, liquid and gas phase oxidation is described in details, and the role of niobium in the prevention of the catalyst from SO2 poisoning is mentioned.  相似文献   
109.
深圳大学微型反应堆的改进   总被引:1,自引:1,他引:0  
介绍深圳大学核技术所近年来对微型反应堆进行的一系列改进 ,包括 :采取特殊措施 ,延长微堆安全运行时间 ,从原来的 6~ 8h ,延长至 40h左右 ,成功研制了治疗肝癌的含稀土元素的放射性玻璃微球 ;建立了超热辐照管和计算机控制的循环跑兔装置 ,扩展了微堆活化分析范围和领域 ;研制出一种新颖、简单、准确 ,且无需添置任何设备的测量堆芯绝对中子通量密度的方法———氙中毒法 .尽管深大微堆具有固有的安全性 ,但它目前处于运行后期 .因腐蚀、疲劳等原因 ,核燃料元件包壳破损的可能性将越来越大 ,为此研制了安全监测计算机系统 ,一旦发生核燃料元件包壳破损时 ,系统能很快监测放射性泄漏 ,这对控制核污染起到十分重要的作用 .但这并不说明深大微堆已安全无事 .国外发生的一系列核泄漏事件昭示人们 ,在核安全管理中 ,人员因素至关重要 .不管放射性物质泄漏多与少 ,影响都很大 ,万万不能麻痹大意  相似文献   
110.
论述了铝合金挤压生产过程中挤压筒锁紧面常发生大帽的原因,并提出了解决该问题的方案。  相似文献   
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