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821.
为了解影响烟秆切割力大小的因素,自制夹具,在万能试验机上对烟秆试样进行了单因素和多因素切割力测试。单因素试验结果表明:无论采用光刀片还是锯齿形刀片,以滑切方式切割的切割力最小;光刀片和锯齿形刀片滑切的切割力都与切割速度呈负相关,与切割角度和试样直径呈正相关。多因素试验结果表明:影响烟秆切割力的因素由大到小依次为切割速度、切割方式、切割角度、试样直径、切割刀片形式;最佳切割方案为滑切,切割速度为300 mm/s,切割刀片为光刀,切割角度为0°,试样直径为26.5 mm。  相似文献   
822.
研究了小麦秸秆丙酸法预处理的反应历程和反应动力学。脱木质素过程分为0~60min的快速脱木质素和60~180min的脱残余木质素2个阶段。通过建立反应动力学方程,获得了丙酸法预处理小麦秸秆的化学反应速率常数和反应级数。温度分别为333、343、353、363K时,速率常数分别为0.0023、0.0028、0.0037、0.005,反应级数为一级。在一定温度和时间条件范围内的动力学研究表明,小麦秸秆的丙酸法预处理的平均反应活化能为26.05kJ/mol,频率因子为26.797L/(mol·min)。  相似文献   
823.
李平  余双强  曾舟华 《安徽农业科学》2012,(30):14925-14926,15019
[目的]开发利用甘薯淀粉加工过程中的废弃物甘薯渣。[方法]对甘薯渣发酵制乙醇的工艺进行了研究,即在温和条件下超声波、超声波结合稀酸和超声波结合稀碱的预处理方法处理木质素后,再在热带假丝酵母和乙醇酵母的共同用下同时将其发酵生产乙醇。[结果]超声波结合稀碱预处理甘薯渣发酵制得乙醇的方法最好,且获得了最佳的工艺条件为固液比1∶15 g/ml、超声波预处理功率250W、时间为30 min,稀碱预处理质量分数为1.0%的NaOH溶液,纤维素酶用量35 IU/g底物,热带假丝酵母与酿酒酵母的接种比1∶1,酵母菌接种量0.75%,在该条件下乙醇产率达到21.4%(重量)以上,与传统工艺相比,产率提高14%。[结论]该研究提高了甘薯深加工产品的附加值,延长产业链,同时可以缓解环境污染问题,有工业推广价值。  相似文献   
824.
污水处理厂污泥中磷回收的研究进展   总被引:2,自引:0,他引:2  
张璇 《安徽农业科学》2012,40(4):2168-2171
对近几年国内外污水处理厂(WWTPs)污泥中磷回收技术的研究进行了总结,概述了人为活动引起的磷的循环过程,详述了污泥中磷回收过程中污泥的预处理、磷的回收方法和工艺技术。在此基础上,对该领域的研究前景进行了展望,总结了各种技术的优缺点,提出应进一步对污泥水解释磷的最佳条件以及有机磷的回收进行探索研究。  相似文献   
825.
Experiments of outburst coal’s gas seepage and deformation under cyclic loading of the stationary gas pressure and different confining pressures are made by “fluid-solid-heat coupling with axis servo seepage system of coal”. The results show that loading route has a significant effect on mechanical properties of coal sample. Although the complete stress-strain curves and one cyclic loading curve present similarity in the overall trend, the stress peak value of coal sample under cyclic loading is lower. Under cyclic loading, the stress-strain curves during loading and unloading don’t overlap. They connect to form a hysteretic loop. The permeability is in close relation with the damage deformation process of coal sample. Under cyclic loading, permeability is increasing during the unloading and decreasing during the loading. The permeability-strain curves during loading and unloading form a hysteretic loop, which is corresponding with the hysteretic loop of stress-strain curves of coal sample.  相似文献   
826.
利用静态顶空-气相色谱法对测定水中甲醇和乙醇进行研究。通过一系列条件实验,对顶空平衡温度,顶空平衡时间,氯化钠加入量等因素进行了优化。并对方法检出限,线性范围,精密度及准确度进行了研究,同时对实际样品进行了测试。2种物质测定结果相对标准偏差均小于6%,加标回收率均在85%~105%。因此该方法适用于水中甲醇和乙醇的同时测定。  相似文献   
827.
介绍了采样引导软件的设计原理,采样引导软件设计是基于集面状区域采样调查引导、数据管理、坐标测量及转换等功能模块开发而进行软件开发,为用户高效、均匀采样调查提供技术支持,为拓展GPSPDA功能拓展提供支撑,为相关软件设计开发提供参考。  相似文献   
828.
荧光原位杂交是一种新兴的分子细胞遗传学技术,广泛应用于各个学科,该文主要介绍了一种在环境微生物研究中可以广泛应用的对固体样品进行荧光原位杂交(FISH)的实验方法。  相似文献   
829.
BACKGROUND: To the authors' knowledge, on the basis of sample type, storage condition, or hemolysis, differences in serum and plasma biochemical values have not been evaluated in orange-winged Amazon parrots (Amazona amazonica). OBJECTIVES: The purpose of this study was to compare values for biochemical analytes in serum vs plasma, fresh vs frozen plasma, and nonhemolyzed vs hemolyzed samples in orange-winged Amazon parrots. We also compared differences in serum and plasma yield from whole-blood aliquots. METHODS: Fifteen biochemical analytes were evaluated in paired serum and plasma, fresh and frozen plasma, nonhemolyzed and hemolyzed serum and plasma samples from orange-winged Amazon parrots (n = 10) using a wet reagent analyzer. Hemolysis was assessed qualitatively (visually) and quantitatively (hemoglobin [Hgb] measured spectrophotometrically). Serum and plasma yields from 500-microl whole-blood aliquots were determined from centrifuged samples. RESULTS: Analyte values significantly differed among sample groups, but were still within published reference intervals, with the exception of increases in potassium concentration in markedly hemolyzed serum and plasma samples. Clinically important changes in hemolyzed serum and plasma samples included increases in potassium, phosphorus, and albumin concentrations and lactate dehydrogenase activity. The degree of hemolysis assigned qualitatively did not correlate with quantitative Hgb concentration. A significantly greater yield of plasma (288 +/- 13 microL) than serum (241 +/- 44 microL) was obtained. CONCLUSIONS: Significant differences may occur in different sample types, however, only changes in potassium, phosphorus, albumin, and lactate dehydrogenase values in hemolyzed samples were considered clinically relevant. Lack of agreement between qualitative and quantitative Hgb concentration indicates the unreliability of visual estimation. Based on higher sample yield, and lack of clinically relevant differences from serum, plasma is a better sample choice for clinical chemistry analysis in birds.  相似文献   
830.
BACKGROUND: A review of the literature revealed limited information about the stability of samples for coagulation testing in dogs. OBJECTIVE: The aim of this study was to evaluate the stability of individual coagulation factors, clotting times, and other parameters of hemostasis in stored canine plasma. METHODS: Citrated plasma samples were obtained from 21 dogs. Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen concentration, and factor I, II, V, VII, VIII, IX, X, XI, and XII activities were measured on an automated coagulation analyzer with commercially available reagents. Antithrombin (AT) activity and D-dimer concentration were measured on an automated chemistry analyzer using validated kits. Samples were analyzed within 1 hour after collection (initial analysis) and once daily for 2 or 4 consecutive days following storage at room temperature (RT) or 4 degrees C, respectively. RESULTS: Storage time at either temperature did not have any effect on PT, factor II, V, VII, X, or XII activities, D-dimer concentration, or AT activity. In contrast, aPTT was significantly prolonged after 72 and 96 hours at 4 degrees C; fibrinogen concentration was decreased after 48 hours at RT; the activities of factors VIII and IX were decreased after 48, 72, and 96 hours at 4 degrees C; and factor XI activity was decreased after 72 hours at 4 degrees C. CONCLUSIONS: Results suggest that storage of canine plasma for 2 days at RT does not have a significant effect on hemostasis test results with the exception of a slight decrease in fibrinogen concentration. In contrast, aPTT and factors VIII, IX, and XI were unstable in refrigerated plasma after 48 or 72 hours of storage.  相似文献   
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