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1.
提出了一种在线测量混炼胶粘度的新方法.该方法以模糊建模技术为基础,综合考虑混炼过程各因素对胶料粘度的影响,建立起胶料粘度的在线测量模型.在模糊建模中,采用T-S模型描述胶料粘度变化的非线性过程,提出了一种基于相似性判别的模糊聚类算法以自动确定合适的聚类组数目,并用实数编码的遗传算法优化全局参数,从而获得了规则简化的、具有较高精度的模糊模型.根据此方法,设计了测量装置,并进行了现场试验.试验结果表明模糊模型输出与实验室测量值基本一致,平均误差较低且最大误差未超过1门尼.该方法较大地提高了橡胶混炼的生产效率,为粘度最优控制奠定了基础.  相似文献   
2.
Waldenström Macroglobulinemia is a low‐grade immunosecretory disorder associated with lymphoid tumours, which is rarely reported in veterinary medicine. In this study, we describe two clinical cases of this rare syndrome in dogs, each characterized by a different onset and clinical course. In one case, a hyperacute onset and aggressive behaviour of the neoplasm was observed. Absolute serum viscosity (SV) was retrospectively evaluated in order to explain clinical findings. Rotational viscosimetry showed good precision in measuring SV. Both dogs had SV values higher than a control groups of healthy dogs although only one subject developed hyperviscosity symptoms and complications. At high paraprotein concentrations, a slight reduction of the M‐component was associated with a marked decrease in SV. Thus, this work suggests that SV assessment is a relevant tool for managing monoclonal gammopathies, whose usefulness should be further confirmed in larger cohorts of dogs.  相似文献   
3.
不同粘度矿物油助剂对除草剂活性的影响   总被引:5,自引:1,他引:5  
室内及温室内测定了10种不同粘度矿物油助剂对除草剂防除苘麻和稗草药效的影响及对玉米苗期的安全性。结果表明,10种矿物油助剂均不同程度地增加了氰草津和烟嘧磺隆防除两种杂草的活性。其中粘度为46 mm2/s (40℃)的矿物油乳剂(MOC46)对供试除草剂药效的增强作用最为明显,其次为粘度32 mm2/s (40℃)的矿物油乳剂。10种助剂对氰草津药效的增强作用大于对烟嘧磺隆。MOC46对除草剂活性的增加由高到低依次为:莠去津、氰草津>莠去津+氰草津、莠去津+烟嘧磺隆、氰草津+烟嘧磺隆>烟嘧磺隆;对玉米苗期安全性依次为:莠去津、烟嘧磺隆、莠去津+烟嘧磺隆>莠去津+氰草津、氰草津+烟嘧磺隆>氰草津。氰草津与MOC46混用对玉米苗期药害较重。  相似文献   
4.
ABSTRACT

1. Enzymes have been used commercially for nearly 40 years and save significant costs through sparing of expensive nutrients but the mechanism by which this is achieved is still debated.

2. The research focused on non-starch polysaccharidase (NSPase) enzymes is used as an example of where greater progress could have been made if the details of the work had been described more fully and the analysis of the data generated had been broader in scope and more critical.

3. Lack of standardisation of the details presented in the materials and methods has been identified as a significant barrier to meaningful retrospective analysis and thus limits advances in the understanding of the mode of action of these enzymes.

4. The identity of the enzyme employed and its activity is often lacking, and more importantly the purity is rarely disclosed. Contaminant activities which are neither listed nor assayed could play a significant role in the responses observed.

5. The dose optimum of most enzymes is often considerably higher than that employed in most studies. Thus studies claiming synergy between two ‘activities’ should ensure that the response is not related to each enzyme simply augmenting the dose of just one activity in the finished feed. This is a common problem, and coupled with the lack of factorial experiments to justify the presence of each enzyme in a multi-enzyme product, it is not surprising that there is still debate as to whether single or multi-enzymes are best suited poultry rations.

6. The three proposed mechanisms for NSPases (viscosity, cell wall and prebiotic) are discussed, and along with their strengths and weaknesses it is suggested that a re-evaluation of each is needed. Viscosity may have to be re-evaluated as being a function not only of the cereal being fed, but of the age of the animal as well. The cell wall theory as described is poorly modelled in vitro and hence the validity of these data is questioned. The prebiotic theory may need significant modification as it appears that the quantities of oligomers produced are insufficient to generate the additional volatile fatty acids (VFA)’s reported. It is likely that all three mechanisms play a role in the responses observed, but the prebiotic mechanism probably plays by far the most important part in low viscosity diets.

7. Future research would be improved if it considered all potential mechanisms when designing a trial. Significant failings are apparent as a result of adherence to tenets in explanation of the results. Most importantly, it should be emphasised that a hypothesis is there to be tested, not defended.  相似文献   
5.
不同水分,温度条件下CO2浓度对大米品质的影响   总被引:5,自引:2,他引:5  
高影  杨建新 《粮食储藏》1997,26(1):3-14
试验选用当年新收获的稻谷加工成的水分为13.9%、14.7%和16.0%的大米,在23℃和33℃的恒温室中,将7种不同浓度的CO2经减压调湿后通入粮堆。定期取样,测定大米的脂肪酸、水溶酸、还原糖、非还原糖、粘度和过氧化物酶活性的变化。试验结果表明:13.9%水分的大米在23℃下储藏,各种浓度CO2对大部分品质指标影响不显著,CO2的保质作用不明显;14.7%水分的大米在23℃储藏,CO2对个别品质  相似文献   
6.
7.
8.
加工参数是影响涂抹型再制干酪物性和微观结构的重要因素.通过测定样品的质构性质、融化性、表观黏度和结合微观结构观察,确定加工参数对涂抹型再制干酪的影响.结果表明:剪切速率、加工温度和时间对样品质构指标和融化距离影响显著(P<0.05),剪切速率由800 r/min升高到1400 r/min的过程中,硬度、涂抹功和黏着性没...  相似文献   
9.
了解壳聚糖溶解特性,对其应用及产品开发有重要意义。分别以甲酸、乙酸、盐酸为溶剂配制成一定浓度的黄粉虫壳聚糖溶液。测定了不同情况下黄粉虫壳聚糖溶液黏度的变化情况,试验结果表明:(1)黄粉虫壳聚糖溶液黏度随溶液浓度的增加而增加;(2)溶液黏度随存放时间的延长而降低;(3)溶液黏度随温度的升高而降低;(4)溶液黏度随溶剂中酸浓度增加和酸性增强而下降。  相似文献   
10.
淀粉的糊化温度是稻米淀粉品质的重要指标,决定淀粉在食品及工业上的用途,也与食用稻米的蒸煮品质密切相关。淀粉的糊化温度可以用淀粉谱仪(如快速淀粉黏滞性测定仪,Rapid Visco analyser,RVA)间接测定,但用淀粉谱仪测定的是淀粉的成糊温度(pasting temperature,PT),它是指淀粉黏度刚开始升高时的温度。在许多情况下,从RVA配套软件 Thermocline for Windows中测定的PT是过高的。提出了两种能够用RVA较准确测定成糊温度的方法。一种是改变参数设置来“筛选”出能反映真正成糊温度的点;另一种是手工记录下淀粉黏度刚开始升高时的时间,利用公式(45/3.8)×(T1-1)+50 计算出稻米的成糊温度。利用手工计算出的成糊温度与通过差示扫描量热仪测定的最高糊化温度呈极显著正相关(r=0.97)。  相似文献   
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