酱卤鸭脖加工过程中危害分析与关键控制点确定

本研究应用HACCP的基本原理与方法,通过对酱卤鸭脖生产过程中的微生物、亚硝酸盐、盐分、肌肉pH值等指标的测定,从生物、化学两方面来分析酱卤鸭脖生产各工艺点中,对酱卤鸭脖质量可能产生的潜在危害,从而确定关键控制点(CCP),CCP为清洗、卤制、包装、灭菌.此外,针对显著危害制定HACCP计划表,为确保酱卤鸭脖质量和安全提供依据.     

Fire blight. Why do views on host invasion by Erwinia amylovora differ?

The fire blight pathogen, Erwinia amylovora, commonly infects flowers and shoots of certain rosaceous hosts and systemic (whole‐tree) invasion sometimes follows. The bacterium may be found in the parenchyma of bark tissue and/or in mature xylem vessels of stem tissue. Views differ on initial sites of multiplication and the optimal route for systemic migration. This article presents the evidence on which the different views are based. There are limited observations on orchard pear and apple trees; in most experimental studies, young apple shoots on potted plants were used. Tissue maturity at the site of shoot inoculation is of prime importance. If xylem vessels are damaged, inoculum may be sucked into the vessels and the bacteria will multiply there. In younger tissue, there is less suction pressure. The critical stem entry site for the invasion of cortical parenchyma seems to be near or above the most recently unfolded leaf. No one has suggested that migration in bark tissue cannot be a major route. If the xylem route is followed, the pathogen needs a means of escape into bark tissue, where typical symptoms develop; means of escape from mature xylem vessels have not been demonstrated and remain a matter for speculation. Published evidence does not seem to support the idea that fire blight is a vascular wilt disease, nor that the extracellular polysaccharide produced by E. amylovora is a toxin and responsible for the wilting symptom seen in the early stages of the disease.     

桑果真空冷冻干燥技术研究

以大十桑果为原料,测得桑果真空冷冻干燥的共晶点和共溶点分别为－23℃和－20℃,冻结的最终温度为－33～－28℃。分析干燥过程中冻干曲线变化趋势;并对影响冻干品质量和产量因素进行测试研究。结果表明：桑果成熟度为八九成熟,装盘时单层平放,以速冻方法冻结,在升华干燥阶段采用二段温控曲线,在解析干燥阶段将加热板最高温度控制在35℃,加工出来的冻干品质量最好,保质期长。     

CO_2气肥对C_3作物产量的影响及增产机理

高光呼吸低光效的C3作物,要比低光呼吸高光效的C4作物对CO2需要量高得多。当CO2浓度增加1000mg/kg时,黄瓜、番茄和青椒可分别增产83.28%、69.12%和49.28%,随之CO2浓度的增加,提高了C3作物的光饱和点,从而提高了光能利用率,增强了光合作用。同时,又抑制了C3作物的光呼吸作用,减少了不必要的能量消耗。     

穴位注射治疗鸭大肠杆菌病的初步研究

为改善家禽胴体品质和减少抗生素使用数量,根据中兽医辨证论治理论和整体的观点,采用穴位注射给药的方法对人工感染大肠杆菌病鸭作治疗保护试验,结果按氟甲砜霉素注射液推荐剂量的40％-50％给药仍有较好的治疗效果,与按100％推荐剂量胸肌注射给药的治疗组比较,差异不显著(P>0.05),而与按50％推荐剂量胸肌注射给药的治疗组比较差异显著(P<0.05),穴位注射给药有较好的疗效。试验结果显示了减少抗生素使用量和改善家禽胴体品质的治疗新方法的可行性。     

喷微灌工程设计中与泵有关的几个问题

水泵选型是否合理不仅关系到喷微灌工程的投资和运行费用，而且在一定程度上决定系统能否正常、安全地运行。本文根据作者自己的设计实践经验，对机压喷微灌工程设计中水泵类型和台数的选择、水泵工作点的确定和调节方法等问题进行了讨论，供设计人员参考。     

土方施工中地下水处理

论述了在土方施工中几种地下水处理的方法及注意事项。     

非共轴螺旋面微孔钻钻尖的数学模型

根据深微孔加工的特点，阐述了研究钻削深微孔用新型钻尖的重要性；建立了新型钻尖后刀面和前刀面的数学模型；介绍了主切削刃的求解以及非共辆螺旋面钻尖刀面的刃磨原理；得到了给定刃磨参数下钻尖的计算机仿真的结果。