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11.
以南京市报恩寺出土的一批宋代丝绸织物为材料分析丝绸固结物的主要成分,然后以表面活性剂等化学试剂配制BE-1揭展剂,对人工老化的固结丝绸织物进行模拟揭展。通过正交试验,研究使用BE-1揭展剂揭展固结丝绸织物的最佳温度、相对湿度以及揭展时间,得出较优的揭展处理工艺方案为:温度30℃,相对湿度70%,揭展时间10 min。采用BE-1揭展剂在此工艺条件下揭展固结丝绸织物时,织物的固结力由原来的147 mN/cm下降为32 mN/cm,揭展后织物的断裂强力、断裂伸长率较揭展前略有提高,硬挺度得到一定改善,色差、红外光谱、热性能以及丝蛋白氨基酸种类和含量等基本上没有变化。试验结果表明,BE-1揭展剂及优化的揭展工艺技术可用于这批出土宋代丝绸文物的揭展。  相似文献   
12.
枯草芽孢杆菌固体发酵豆粕条件的优化   总被引:1,自引:0,他引:1  
本试验采用枯草芽孢杆菌对豆粕进行固体发酵,通过正交试验探讨不同碳源组合、发酵时间、培养温度、水分比例、接种菌量等因素对发酵豆粕粗蛋白质增加率和蛋白质水解度的影响。结果表明,影响枯草芽孢杆菌固体发酵豆粕粗蛋白质增加率的条件因素的主次顺序为玉米粉比例>培养时间>温度>麸皮比例>水分比例>次粉比例>接种菌量,表观分析固体发酵条件最佳组合为A3B1C3D3E2F2G1,粗蛋白质增加率达到28.05%;影响发酵豆粕蛋白质水解率的条件因素的主次顺序为温度>培养时间>玉米粉比例>接种菌量>麸皮比例>次粉比例>水分比例,表观分析固体发酵条件最佳组合为A2B3C1D3E3F3G1,蛋白质水解度达到46.46%。枯草芽孢杆菌固体发酵豆粕的粗蛋白质增加率与蛋白质水解率存在明显的正相关(R2=0.556)。  相似文献   
13.
The objectives of this study were to assess changes in nutritional status/body condition score, percentage pregnancy and calving rate in Zebu cows and to establish the relationship between body condition score loss and postpartum interval to resumption of ovarian activity. A total of 198 cows and postpubertal heifers of the Tanzanian Shorthorn Zebu kept under a traditional management system were randomly selected from 200 smallholder herds. Factors investigated during bi-weekly visits include body condition score (BCS), heart-girth circumference, milk yield and reproductive status of the animals, pregnancy/non-pregnancy and cyclicity/non-cyclicity. Local weather conditions and dates of occurrence of other reproductive events such as calving were also recorded. Calvings occurred all year round but with a strong seasonal distribution characterized by annual peaks observed between April and July. The annual calving pattern was closely related to rainfall, with peak precipitation occurring a few months before peak calving. The overall percentage pregnancy varied from 30% to 50% throughout the year. Postpartum cows exhibited minimum mean BCS and heart-girth circumference 12–14 weeks after calving, and cows with BCS loss >1 point exhibited the longest time interval from calving to onset of ovarian activity.  相似文献   
14.
本研究选用72只6周龄京白鸡,随机分为A、B、C、D、E和F六组,分别饲喂钙、锌水平不同的日粮(各组锌、钙分别为:21.5ppm,0.95%;21.5ppm,1.95%;21.5ppm,2.95%;49ppm,0.95%;49ppm,1.95%;49ppm,2.95%),进行为期30天的饲养试验。试验中观察增重和临床变化;饲养结束时,取全血、羽毛、胫骨、肝和肾等组织的样本,测定其锌、钙、铁、铜、锰等元素的含量。试验结果是,D组增重和发育良好;A组稍次于D组;其他各组出现程度不同的临床症状,并且这些组所测组织锌含量明显低于D、A组,且其羽毛铁、骨铜、羽毛锰含量明显升高,而羽毛铜、肾铜及肾锰则显著降低。  相似文献   
15.
蚕蛹油微胶囊的制备   总被引:3,自引:0,他引:3  
为了改善蚕蛹油的加工性能和延长其保质期,以大豆蛋白和β-环状糊精为壁材,采用喷雾干燥法制备蚕蛹油微胶囊。依据蚕蛹油微胶囊乳状液的稳定性检测指标,确定壁材大豆蛋白和β-环状糊精的质量比为1∶1。通过正交试验确定制备蚕蛹油微胶囊的最佳工艺条件为:芯材(蚕蛹油)与壁材的质量比为1∶2,乳状液中固形物的质量分数为20%,均质压力25MPa,喷雾干燥的进风温度190℃。在此工艺条件下制备蚕蛹油微胶囊的包埋率为91.2%。  相似文献   
16.
In a short time feeding experiment it was shown that the liver weight of cod was significantly reduced in prawn-fed cod compared to sand-eel-fed cod. The dry weight and the protein content of the muscle were not significantly reduced. It is concluded that short time energy deprivation of cod primarily affects the liver. The results futher support the view that the food type and ration of cod can produce anomalous effects in field studies of e.g. parasite induced liver weight decrease in cod.  相似文献   
17.
To assess the stress level of cheetahs reared in Japan and to identify the prime components of the climatic conditions that affect their thermal stress, fecal corticosterone was monitored for 8 months from May to the following January. A total of 203 fecal samples were gathered in the morning from seven adult cheetahs that were kept at a zoological garden in Wakayama, Japan. Cheetahs were on exhibit singly or together with a harmonious conspecific during the day, but housed singly at night. Although the monthly fluctuation in corticosterone concentrations was not significant, the concentrations were relatively low during the summer season. Individual differences among cheetahs and the interaction effect between individual and month on the corticosterone concentrations were significant. Whereas the corticosterone concentrations negatively correlated with air temperature, they were positively correlated with the amount of rainfall. The highest air temperature and the amount of rainfall were extracted as the prime factors affecting corticosterone concentrations. These results suggest that cheetahs reared in Japan are somewhat subjected to thermal stress, particularly on cooler and/or rainy days.  相似文献   
18.
In the veterinary profession, the body condition score (BCS) plays an important role in the assessment of patients. It is a subjective, tactile method of evaluating body fat and muscle mass and is used in numerous species. Recognizing obesity (or the contrary, emaciation) is important for veterinarians treating reptiles and could be facilitated by a BCS. An existing form of body condition assessment already used is the body condition index (BCI), where the residuals from a regression of body mass on body length are calculated. Therefore, the goal of this study was to provide practitioners with a BCS system for corn snakes (Pantherophis guttatus) and to test it against the BCI. A total of 22 corn snakes (Pantherophis guttatus), stationed at the “Auffangstation für Reptilien” in Munich (reptile rescue centre, RRC), were subject of this study. Each had the following measurements taken: body weight (BW), snout–tail tip length (STL), snout–vent length (SVL) and circumference in the middle (C). Manual palpation of spine, area between vertebral spinous and transverse process, ribs and neck of each snake was performed by three veterinarians and assigned to specific scores by each examiner. A BCS (mean of examiners’ scores) was given to each snake according to manual palpation. The BCS system was chosen to be out of 5 in 0.5-point steps with 2.5 considered as ideal BCS. In the studied snakes, the BCS ranged from 1.5 to 3.5, with a median of 2.5. The median BW was 309 g (75–967 g), the median STL was 123 cm (79–153 cm), the median SVL was 104 cm (73–133 cm) and the median C was 7.5 cm (4.3–11 cm). BCS and BCI were positively correlated. A BCS includes a manual palpation of the animal and thus gives the examiner additional information to the objectively measured/calculated index.  相似文献   
19.
土壤种子库是矿区植被恢复的重要因素,其特征在一定程度上反映了区域的植被恢复潜力.本研究通过样地调查和室内萌发法对乌海新星煤矿区3种不同干扰条件下的土壤种子库及与其地表植被之间的关系进行分析.结果表明:1)新星矿区土壤种子库共有18种植物,隶属于7科16属,物种生活型以多年生草本植物为主;2)新星矿区土壤种子库平均储量较...  相似文献   
20.
We investigated the effect of probiotics from anaerobic microflora with prebiotics (synbiotics) on growth performance, noxious gas emission and fecal pathogenic bacteria populations in growing pigs. The basal diet, which contained approximately 25% corn, 24% whey, 12% wheat and 12% soybean meal, was supplemented alternatively with 0.15% antibiotics (US diet), prebiotics and 0.2% probiotics from anaerobic bacteria (BS diet), yeast (YS diet), mold (MS diet) or compounds (CS diet). One hundred and fifty pigs were fed an experimental diet for 15 days. Although the growth performance was not affected by supplemental synbiotics, the BS group showed higher dry matter and crude protein digestibility. The BS group decreased fecal ammonia and amine gas emissions, and increased fecal acetate gas emission compared with the US group. All synbiotics groups decreased in fecal propionate gas emission. Fecal Escherichia coli population was lower in the synbiotics groups than in the US group. Therefore, the results of the present study suggest that synbiotics exert similar effects with antibiotics on the nutrient digestibility and fecal microflora composition in growing pigs. Moreover, synbiotics can also decrease the fecal noxious gas emission in growing pigs.  相似文献   
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