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91.
生活污水净化沼气池是运用沼气技术分散处理居民生活污水和粪便污水,具有投资小、建造简单、不占用土地、耗能少和具有较好的社会效益等特点。分析了生活污水净化沼气池原理、结构以及污水分流制和合流制两种工艺流程,重点介绍了生活污水净化沼气池的施工工艺。  相似文献   
92.
93.
高质量浓度苯胺工业废水的治理   总被引:2,自引:0,他引:2  
介绍了采用HSB微生物法处理高质量浓度苯胺工业废水的治理方法,可获得很好的处理效果,出水能达到国家一级排放标准。  相似文献   
94.
In view of the different of the underground heat storage water tank of solar position arrangement, make use of the Fluent software program numerical simulation and calculation, it is concluded that under different conditions the heat storage water tank temperature field distribution of the soil around. At the same time, establishing physical model and mathematical model of underground heat storage water tank and combined with practical engineering, verify the underground storage tank for heat and energy storage, to obtain the relationship between the tank roof loss and total heat release. Calculation results show that under the same conditions, outdoor storage tank at the top of the heat dissipating capacity to reduce, so the method can be used to offset at the top of the energy required collector to reduce, so the method can be used to offset this part of the energy required collector area of the cut, improve thermal efficiency and reduce the user store hot water tank of the store.  相似文献   
95.
文章旨在分析双层桨叶单轴混合机的结构和混合原理。通过对混合机的机体、转子、卸料门及控制机构、传动部分、液体添加系统、气包喷吹系统关键结构的详细分析,了解其独特的混合原理和优良特性。该机具有混合均匀度高CV≤5%(可达2%~3%)、残留量低(≤0.1%)、生产效率高、使用维修方便等特点,在国内外饲料添加剂预混合生产中应用越来越广泛。  相似文献   
96.
AIMS: To assess the sensitivity and specificity of a bulk tank milk (BTM) antibody enzyme-linked immunosorbent assay (ELISA) to detect likely infection of a dairy herd with bovine vi- ral diarrhoea virus (BVDV). The ELISA was subsequently used to estimate the prevalence of likely infected herds in parts of the North Island of New Zealand.

METHODS: BTM samples from 724 randomly selected dairy herds in the Waikato, Bay of Plenty and Northland regions of New Zealand were tested for BVDV antibodies. From this group, 20 herds were again randomly selected from each of the quartiles of the ELISA percentage inhibition (%INH) result. From each participant herd, serum from 15 randomly selected calves aged 6–18 months and 15 cows was collected and tested using an indirect blocking ELISA for BVDV antibodies.

RESULTS: Among serum results from calves from 50 herds available for analysis, 34 (68%) herds were classified as likely non-infected (0-3 seropositive among 15 calves) and 16 (32%) as likely infected (5–15 seropositive among 15 calves). Receiver- operator characteristic (ROC) analysis identified an optimal cut-off for BTM of 80%INH associated with 81% sensitivity and 91% specificity for likely herd infection. The prevalence of BVDV antibodies in cows within herds and %INH for BVDV in bulk milk were positively correlated (p<0.01). The association between bulk milk %INH and the prevalence of BVDV antibodies in calves was stronger than the same association in cows. Based on the threshold of 80%INH, the 95% confidence interval (CI) for prevalence of likely infection in the 724 herds in the Waikato, Bay of Plenty and Northland regions of New Zealand was 12–17%. Vaccination against BVDV was not significantly associated with the likely infection status of the herd based on prevalence of BVDV antibodies among calves.

CONCLUSION: An ELISA test result for BVDV antibodies in BTM ≥80%INH can be used as a threshold to indicate the presence of likely infection with BVDV in dairy herds in New Zealand, with 81% sensitivity and 91% specificity.  相似文献   
97.
A 3‐week‐old Pony of the Americas foal presented with a history of respiratory distress presumed to result from Actinobacillus equuli pleuropneumonia and septic arthritis. Failure of transfer of passive colostral immunity was suspected, but not confirmed, based on a history of the foal being separated from its dam shortly after parturition. Transient improvement was noted following thoracocentesis and removal of approximately 600 ml of pleural fluid but progressive clinical signs of congestive heart failure developed. Fibrinous pericarditis with evidence of cardiac tamponade was subsequently diagnosed via thoracic ultrasonography. Early clinical signs of cardiogenic shock were identified and fibrinopurulent exudate removed through a catheter placed with ultrasound guidance into the pericardium. The foal experienced cardiorespiratory arrest during the procedure and died despite resuscitative efforts. Post mortem examination identified extensive hypertrophy of the pericardium, septic arthritis, mild pleural effusion and focal bronchopneumonia. This report details the clinical evaluation, haematology, treatment and post mortem pathology of a foal with Actinobacillus equuli associated fibrinous pericarditis, as well as a brief review of cardiac tamponade.  相似文献   
98.
This case report describes the history, clinical findings, clinical pathology and diagnostic imaging of 2 cases of septic osteitis of the proximal sesamoid bones in foals. Treatment with doxycycline (10 mg/kg bwt per os b.i.d.) was successful in treating both of these cases.  相似文献   
99.
基于RNGk-ε紊流模型和雷诺时均N-S方程,运用CFD商用大型软件对箱涵式进出水流道立式轴流泵装置进行了三维流动仿真计算及水力特性的优化设计。通过先部分后整体的方法先独自对箱涵式进水流道进行优化计算,而后在整体泵装置上对箱涵式出水流道进行优化计算。进水流道的优化以出口断面流速均匀度和水力损失为目标函数,出水流道的优化则以泵装置效率和水力损失为目标函数。通过数值计算得出,优化后箱涵式进水流道的水力损失由7.52cm降低到3.49cm,进水流道出口流速均匀度由42.41%提高到89.11%,进水流道的悬空高度H和进水喇叭管与叶轮间的连接角度α对进水流道水力特性的影响显著,设计时应该重点考虑。箱涵式出水流道的水力损失由87.15cm降低到76.37cm,出水流道的设计应重点关注导流墩与出水喇叭管的半径差Δr和出水导流墩的半径R,合适的出水导流墩半径在0.75倍导叶出口直径左右。泵装置模型试验在叶片安放角-4°时,设计工况下泵装置效率达到75.0%,泵装置最高效率为75.67%,高效区运行范围较宽;对比数值计算和模型试验的结果可以发现误差最大处低于5%,整体性能曲线的趋势相对良好,说明数值模拟对于泵装置的优化是合理的,对于实际工程具有指导意义。  相似文献   
100.
面向高校智库建设,探讨高校图书馆的功能定位与服务创新策略。采用文献调研、网站调研和案例分析法,从高校图书馆与智库的关系出发,阐述高校图书馆在高校智库建设中的功能定位。目前高校图书馆虽不能成为智库,但与智库有着特殊渊源和联系。高校图书馆应从资源建设创新、团队建设创新、平台构建创新、服务模式创新和效果提升创新5个方面为高校智库建设提供文献保障和信息服务。  相似文献   
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