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无缝烟夹不同针尖处理对烤后烟叶孔径的影响 总被引:1,自引:1,他引:0
为优化无缝烟夹装置设计,充分发挥无缝烟夹装烟方式的优势,对不同直径、不同形状针尖及不同方向的无缝烟夹烤后烟叶的针孔面积进行了比较研究。结果表明:不同直径烟针相比,3 mm直径无缝烟夹烤后针孔面积小于5 mm直径无缝烟夹;无缝烟夹在3 mm直径条件下,扁形针尖平行处理烤后针孔面积最小;在5 mm直径条件下,圆形针尖平行处理烤后针孔面积最小。 相似文献
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响应曲面法优化高粱挤压最佳操作参数的研究 总被引:1,自引:0,他引:1
以高粱为原料,研究系统操作参数,包括:物料含水率、喂料速度、螺杆转速、机筒温度对目标参数的影响,并以响应曲面法优化最佳操作参数,优化得到的最佳操作参数为:物料含水率15.77%,喂料速度26.97r/min,螺杆转速181.20r/min,五区温度158.28℃。 相似文献
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The aim of this study was to develop a novel oil-in-water (O/W) emulsion as adjuvant diluents (AD) for live vaccine against classical swine fever (CSF) that could effectively enhance the immune effect of vaccine.The AD was prepared by high-pressure homogenization technique.Formulations and preparation parameters were optimized with response surface design.Its stability, particle size, polydispersity (PDI) and Zeta potential were characterized.The humoral immune response and cellular immune response of the AD were evaluated with BALB/c mice by intramuscular injection.The particle size of the AD prepared by optimized formulation and parameters was 100.4 nm, PDI was 0.147, and Zeta potential was —28.7 mV.The experiment results showed that the AD had good stability.The AD was inoculated combined with live vaccine against CSF into BALB/c mice by intramuscular injection.The results showed that the live vaccine against CSF specific immune responses could be evoked in mice by co-inoculation with AD and vaccine.The cellular immune response levels in co-inoculated groups were significantly higher than control group (P<0.05), with obvious phenomena of higher levels of IFN-γ, IL-6 and IL-4 in serum.The result revealed that cellular immune capability significantly improved with the AD.The results strongly revealed that cellular immune capability significantly improved by introducing AD for effective immune-adjuvant for live vaccine against CSF. 相似文献
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During early lactation, dairy cows may present a transient immunosuppressive state and develop anaplasmosis caused by Anaplasma marginale. In this study, clinical anaplasmosis in dairy cattle in the Thrace region of Turkey was investigated with respect to within-herd prevalence, vertical transmission, and genetic diversity. In March and September 2015, thirty lactating cows showed primary clinical signs of anaplasmosis, including fever, anaemia, decreased milk yield, anorexia, and laboured breathing. Symptoms disappeared in most cows after administration of long-acting oxytetracycline, but nine of them (30%) died. Following diagnosis based on clinical signs, microscopy and molecular findings, blood samples were collected from apparently healthy lactating cows (n = 184), pregnant heifers (n = 39) and newborn calves (n = 24). DNA was extracted from each sample and analyzed for the presence of major surface proteins (MSPs) of A. marginale, followed by sequencing to assess diversity of isolates. Microscopic examination of erythrocytes revealed A. marginale inclusion bodies in symptomatic cows. Examination of thin blood smears showed 3.8% of the lactating, clinically asymptomatic, cows to be infected with A. marginale, while nPCR detected 31.0% positive. A. marginale infection was not detected in pregnant heifers by either method. Congenital infection was found in one calf by nPCR. This is the first report of transplacental transmission of A. marginale in Turkey. The MSP4 sequence analyses showed high genetic diversity among the isolates, presenting 97.6-99.6% homology at the amino acid level. The sequences of MSP1a amplicons revealed genetic diversity providing three new tandem repeats. 相似文献
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The aim of the study was to assess the influence of high-intensity laser therapy (HILT) on vein diameter and on body surface temperature changes in the tarsal joint area in a group of clinically healthy racehorses. The hypothesis of the study was that HILT increases vein diameter and body surface temperature in healthy tissue. The study involved 16 Thoroughbreds being subjected to ultrasonographic examination to assess changes of diameter of the cranial branch of the medial saphenous vein and thermographic examination to indicate temperature change of the dorsal surface of the tarsal joint, just before and immediately after HILT treatment. Vein diameter and mean surface temperature of the tarsal joint significantly increased after HILT treatment. In addition, the study was the first to describe the photothermal effect of HILT in healthy horses. More studies are necessary to specify the parameters of the procedure, that is, wavelength, energy density, or time of the procedure, depending on the patient’s individual characteristics and type of tissue. 相似文献
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Dissolved oxygen (DO) is a key ecological factor to measure the quality of water in the aquaculture. As the pond water body is affected by the breeding environment, the spatial distribution of DO shows a certain law in the entire pond. Therefore, to simulate the distribution of DO in aquaculture waters and grasp the temporal and spatial variation of DO is the key to achieving precise regulation of DO. For this purpose, this paper proposed a method for simulating the temporal and spatial distribution of DO in pond culture based on a sliding window-temporal convolutional network together with trend surface analysis (SW-TCN-TSA). This paper first utilized SW to construct DO data sets with different prediction durations, and then used the improved TCN model to realize one-dimensional time series prediction for DO at single monitoring point. Based on the prediction results of DO, a TSA method was performed on the predicted values of DO at the extreme moments of all discrete monitoring points, so as to realize the simulation of the temporal and spatial distribution of DO in the pond. Experimental results show that the SW-TCN model has better prediction performance for one-dimensional time series prediction of DO. Compared with traditional deep networks, such as CNN, GRU, LSTM, CNN-GRU and CNN-LSTM, the values of evaluation indicators (MSE, MAE and RMSE) have been greatly improved. In the process of trend surface fitting, all fitting R2 of DO at different water depths are higher than 0.9, indicating that the TSA can accurately reflect the temporal and spatial distribution of DO. This method can provide a basis for the prediction and early warning of DO in the three-dimensional space of the pond and has high practicability in aquaculture. 相似文献
29.
为构建猪链球菌(Streptococcus suis)蛋白表面展示系统,本研究通过序列分析,确定猪链球菌的LPxTG蛋白及其信号肽(SP)和胞壁锚定基序(CWA),通过PCR扩增Peno-SP、GFP、CWA的DNA片段并融合,构建强启动子Peno控制表达编码SP-GFP-CWA融合蛋白的DNA片段,将该重组DNA片段连接pSET2载体,获得蛋白表面展示质粒,转化猪链球菌,构建得到以GFP为报告蛋白的猪链球菌蛋白表面展示系统。结果显示,利用猪链球菌的10个LPxTG蛋白及其SP和CWA序列,构建了10个含有Peno-SP-GFP-CWA融合片段的重组pSET2表面蛋白展示质粒pSsPSD1至pSsPSD10,分别转化猪链球菌05ZYH33,PCR鉴定显示其中7个转化猪链球菌。采用western blot初步检测其展示蛋白,结果显示,7个转化阳性菌株均能有效表达GFP蛋白,以成熟GFP条带为指标,均表现出了一定的外源GFP表面展示水平,分别命名为SsPSD1、SsPSD2、SsPSD4、SsPSD7-SsPSD10,其中SsPSD1、SsPSD4、SsPSD8和SsPSD9表面展示水平相对较好,在猪链球菌表面展示外源蛋白方面具有很好的潜力。本研究首次尝试建立猪链球菌蛋白表面展示系统,为猪链球菌表面递呈外源蛋白或抗原提供了新的策略。 相似文献
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应用响应面法和经过改进的非支配排序遗传算法(NSGA-II)进行悬架结构参数优化.在ADAMS/Insight软件中进行设计参数的灵敏度分析,针对灵敏度较大的设计参数,建立车轮定位参数在车轮跳动过程中最大变化量的2阶响应面近似数学模型对该模型进行稳定性分析,并且应用加入精英保持策略和去除重复个体算法的NSGA-II优化算法对多目标响应面模型进行优化求解.优化结果表明该方法具有较高的精确性与有效性. 相似文献