蓄热式炉排烟风机节能改造实践

通过对蓄热式炉排烟风机系统运行现状和调节方式进行分析,发现排烟风机的吸风量与加热炉的排烟量相比富裕量较大,易造成加热炉负荷较低时风机工作点接近喘振区,使得风机噪声和振动较大。针对此问题对目前的风机设备进行性能测试和优化设计,改善风机设备与系统工艺的匹配程度,提高风机系统的运行效率,有效地降低风机能耗。     

高炉带压切换风机的过程控制

在单台风机对单台高炉的供风网络结构下,传统的切换风机操作不允许风机并联对高炉供风,即每次倒风机必须在高炉休风时才能进行。通过采用新的带压切换风机操作技术,实现了在一段时间内2台风机并联对1座高炉供风,减少了高炉休风次数,该操作技术安全可靠。     

论收尘风机的节能

针对收尘风机富余量过大,风机结构存在不合理的状况,论述了以风机集流器、叶轮为改造重点,对风机进行的节能和提高效率的改造。     

热风炉助燃风机系统设备选型及设计

详细介绍了热风炉助燃风机系统设计,涉及不同条件下的助燃风机配置,以及根据风机性能曲线、风机出口风量、风机出口压力进行设备选型。此外,还介绍了根据实际工况对风机参数进行换算,应用变频技术提倡节能及采取降噪措施促进环保。     

风机不平衡研究

研究了风机不平衡的原因、特征和类型,给出了两种校正风机不平衡的有效方法,对正确的判断风机不平衡故障,确定风机不平衡的类型,消除风机不平衡引起的振动有着重要的现实意义。     

风机振动原因分析及防治

对风机振动原因进行了综合分析 ,从设备、工艺和维护几方面分析了可能导致风机振动的因素 ,提出多种措施 ,改善了风机作业状况、工作环境 ,有效的解决了风机振动问题 ,延长了风机使用寿命。     

宝钢og风机振动原因分析及处理

对宝钢一炼钢OG系统作了简单介绍,并根据OG风机目前的运行状况,对影响OG风机稳定运行的原因作出分析,鉴于目前OG风机主要故障主要是平衡不良引起,从整个OG系统上分析了导致叶轮积灰原因,以及风机本体因素对动平衡的破坏,并提出了解决OG风机平衡破坏的一些处理方案。     

高效节能风机在助燃风机节能改造中的应用

分析了炼铁热风炉助燃风机系统普遍存在的高能耗问题,以8#高炉热风炉助燃风机为例,将高效节能风机技术应用在该助燃风机的节能改造中,对节能效果进行计算分析,结果表明更换高效节能风机的节能效果明显。     

高温循环风机在铝合金热处理设备中的应用

根据风机气流流动原理对风机进行了分类,并对相关风机进行了介绍。分析了不同产品和形状的工件所对应的空气流场,确定了流场风机的类型和参数是保证设备性能优劣的关键。通过对风机选型的总结和分类,为热处理设备高温风机选型的合理性和经济适用性提供一定的参考。     

基于PLC控制的风机变频节能技术的研究与应用

阐述了风机变频调速的节能原理,依据风机类负载特性,对风机节能运行作了分析和比较,举例说明在热处理设备中通过对风机变频的闭环控制,达到了显著的节能效果。     

利用振动总量及频谱分析综合诊断风机异常振动

介绍一种利用振动总量结合频谱分析进行设备故障诊断的简单方法，并列举了一个管加工厂回火炉９号循环风机异常振动的诊断实例。     

120t转炉煤气回收及一次除尘自动控制系统技术应用

济钢120t转炉煤气回收及除尘自动控制系统采用PLC控制技术，采用以太网通讯传输技术构成二级通讯网络，完成系统间的通讯。可以实现风机自动调速、煤气自动回收、CRT集中监控等功能。系统自投运以来，性能稳定，满足了工艺设备的要求，实现了先进技术与适用性的有效结合。     

冷却风机与STM辊道的同步控制

对斯太尔摩风冷线的风量控制系统通过网络进行同步控制改造，实现对不同轧制品种的自动识别，使冷却风机风门开口度的调节与辊道速度的变化具有快速反映能力及跟随性，从而实现控冷效果，提高产品质量的问题作了介绍。此方法可以在相关问题上得到广泛推广应用。     

XWD40型电除尘器技术改造

针对XWD40电除尘器因设计缺陷及构件磨损等原因造成的除尘效率低的问题，济钢第二烧结厂对气流分布装置、极线、密封保温门、绝缘套筒等关键构件进行了技术改造。电除尘器改造后运行效果良好，消除了极板挂灰、电晕极变形、漏风等现象，测试表明，烟气排放量1^#机由235mg／m^3降为24mg／m^3，2^#机由280mg／m^3降至58mg／m^3；电场气流顺畅，相配套的两台No18D除尘风机电流由290A降为220A。     

Apparent digestibility of minerals by lactating cows from a total mixed ration supplemented with poultry litter

Apparent digestibility of minerals by lactating cows from a multiple-component, conventional Israeli TMR (control) and from a TMR containing 10% poultry litter (DM basis) was examined. Ten cows in early lactation were divided into two groups of similar performance (39 kg of milk/d) and fed for ad libitum intake the two TMR for 28 d. Poultry litter contributed, as a percentage of total requirements, 44.4% of Ca, 41.0% of P, 32.0% of S, 22.8% of Mg, and 25.9% of K. Apparent digestibility of the macroelements was higher for cows fed the TMR supplemented with poultry litter than for those fed the control TMR. Apparent digestibility of the control TMR was 22.3% for Ca, 29.4% for Mg, 39.1% for P, and 62.2% for S; the apparent digestibility of the treatment TMR was 30.1% for Ca, 45.6% for Mg, 45.3% for P, and 65.6% for S. Poultry litter contributed the entire requirements of Zn, Mn, and Co; 56% of Cu; and 32% of Se. The apparent digestibility of the control TMR was 15.6% for Cu, 39.6% for Zn, 8.51% for Mn, 42.8% for Co, and 41.6% for Se, and the apparent digestibility of the treatment TMR was 27.9% for Cu, 54.0% for Zn, 17.8% for Mn, 37.0% for Co, and 63.9% for Se. Poultry litter is a good source of macro- and microelements for lactating cows and, at 10% of the TMR, could ensure against mineral deficiencies.     

Detection by denaturing gradient gel electrophoresis of an Arg1689Cys mutation in a Chinese patient with mild hemophilia A

OBJECTIVE: To examine the ease of endotracheal intubation on the ground for various rescuer positions. METHODS: Six female and 18 male emergency medical technicians were asked to intubate a Laerdal Megacode Trainer placed on the ground. Rescuers assumed the following positions in random order: prone, sitting, kneeling at the mannequin's head, and straddling the chest. The authors measured times 1) for changing from mask ventilation to assuming intubation position and 2) from touching the laryngoscope to putting it down. Incidences of esophageal tube placement and clicks (possible tooth damage) were noted. The rescuers rated their satisfaction with each position on a six-point scale (1 = very good, 6 = insufficient). Total intubation times of the other three positions were compared with that for prone by rank order test for paired observations. Handling, esophageal positions, and clicks of the other three positions were compared with those for prone by sign test for paired observations. A Bonferroni correction (factor 12) was applied. RESULTS: Mean total intubation times (in seconds) were 11.8 +/- 3.3 for prone, 13.9 +/- 4.7 for sitting, 11.4 +/- 4.5 for kneeling, and 16.2 +/- 5.8 for straddling. The difference between straddling and prone was statistically significant (p < 0.005). For handling, the results were for prone 3.0 +/- 1.4, for sitting 3.1 +/- 1.1, for kneeling 2.2 +/- 0.6, and for straddling 2.8 +/- 1.4. Esophageal positions occurred for prone 1, for sitting 1, for kneeling 2, and for straddling 3. Clicks were counted for prone 2, for sitting 1, for kneeling 1, and for straddling 0. CONCLUSIONS: All tested positions provide satisfactory conditions for intubation on the ground. The straddling position requires statistically, but not clinically, significantly more time for intubation than does prone and may be an important backup position if access from behind the patient's head is impossible.     

Avoidable mortality among psychiatric patients

Avoidable mortality is a selection of causes of death considered to be amenable to health care and thereby used as an indicator of the quality of health care. In this study avoidable mortality for more than 30,000 psychiatric patients discharged from any hospital of Stockholm County between 1981 and 1985 has been followed up in the Cause of Death Register for the period 1986-1990. Standardised rate ratios were calculated for different groups of psychiatric disorders compared to the general population of Stockholm County for indicators of avoidable mortality, suicide, other mortality ("unavoidable") and causes possibly related to treatment with psychotrophic drugs. As expected, the psychiatric patients had the most pronounced elevated risk for suicide. i.e. 6- to 24-fold compared to the general population, and noticeably more elevated for women. It is also noteworthy that the relative mortality risks for diagnoses amenable to medical interventions and potential side-effects of psychotrophic drugs are higher than for other causes of death ("unavoidable"). The relative risks for avoidable mortality were 4.7 for men and 3.8 for women and for diagnoses possibly related to side-effects of psychotrophic drugs, 7.2. The relative risks for "unavoidable" mortality were 3.4 for men and 3.2 for women. The excess avoidable mortality rates for psychiatric patients and the elevated suicide risk, especially for female patients, are warning signals of shortcomings in psychiatric care that warrants further investigation.     

Hip fracture incidence among elderly Asian-American populations

This study estimated national age- and sex-specific nontraumatic hip fracture incidence rates for elderly Chinese Americans, Japanese Americans, and Korean Americans. Based on a 50 percent sample of 1992 Medicare enrollees with the race/ethnicity code "Asian" and "other," cohorts of persons with distinctive Chinese (n = 24,366), Japanese (n = 28,762), and Korean (n = 5,470) names were followed passively for 2 years for a hospitalization with a diagnostic code indicating hip fracture. Cohorts of whites and blacks were followed for comparison. Year of immigration was deduced from the year of issuance of the Social Security number. Age-adjusted hip fracture incidence was lower for all three Asian-American groups than for whites. For females, the standardized fracture ratio relative to whites was 30.1 for Chinese, 73.2 for Japanese, and 52.8 for Koreans; for males, the standardized fracture ratio was 41.9 for Chinese, 58.1 for Japanese, and 90.7 for Koreans. Persons whose Social Security numbers were issued after the immigration Act of 1965 had an adjusted relative risk of 1.37 (95% confidence interval 1.05-1.78) compared with those in the US before that year, after adjustment for age, sex, and ethnic group.     

Comparative evaluation of FUNGITEST and broth microdilution methods for antifungal drug susceptibility testing of Candida species and Cryptococcus neoformans

The FUNGITEST method (Sanofi Diagnostics Pasteur, Paris, France) is a microplate-based procedure for the breakpoint testing of six antifungal agents (amphotericin B, flucytosine, fluconazole, itraconazole, ketoconazole, and miconazole). We compared the FUNGITEST method with a broth microdilution test, performed according to National Committee for Clinical Laboratory Standards document M27-A guidelines, for determining the in vitro susceptibilities of 180 isolates of Candida spp. (50 C. albicans, 50 C. glabrata, 10 C. kefyr, 20 C. krusei, 10 C. lusitaniae, 20 C. parapsilosis, and 20 C. tropicalis isolates) and 20 isolates of Cryptococcus neoformans. Overall, there was 100% agreement between the methods for amphotericin B, 95% agreement for flucytosine, 84% agreement for miconazole, 83% agreement for itraconazole, 77% agreement for ketoconazole, and 76% agreement for fluconazole. The overall agreement between the methods exceeded 80% for all species tested with the exception of C. glabrata (71% agreement). The poorest agreement between the results for individual agents was seen with C. glabrata (38% for fluconazole, 44% for ketoconazole, and 56% for itraconazole) and C. tropicalis (50% for miconazole). The FUNGITEST method misclassified as susceptible 2 of 12 (16.6%) fluconazole-resistant isolates, 2 of 10 (20%) itraconazole-resistant isolates, and 4 of 8 (50%) ketoconazole-resistant isolates of several Candida spp. Further development of the FUNGITEST procedure will be required before it can be recommended as an alternative method for the susceptibility testing of Candida spp. or C. neoformans.     

Variance component estimation and multitrait genetic evaluation for type traits of dairy goats

Covariance components for final score and 13 linear type traits of dairy goats were estimated by multitrait REML using canonical transformation with an animal model. Data were 10,932 type appraisals from 1988 through 1994 from herds with > or = 40 appraisals. Heritabilities were estimated as 0.27 for final score, 0.52 for stature, 0.29 for strength, 0.24 for dairyness, 0.38 for teat diameter, 0.21 for rear legs, 0.32 for rump angle, 0.27 rump width, 0.25 for fore udder attachment, 0.25 for rear udder height, 0.19 for rear udder arch, 0.25 for udder depth, 0.33 for suspensory ligament, and 0.36 for teat placement. Genetic correlations of linear type traits and final score were positive except for dairyness (-0.15) and teat diameter (-0.10); the largest correlations with final score were 0.66 for fore udder attachment, 0.44 for rear udder arch, 0.36 for rump width, and 0.30 for strength. The largest positive correlation among linear traits was 0.63 for stature and rump width; the largest negative correlation was -0.51 for strength and dairyness. Multitrait evaluations were calculated with data from all herds. Correlations between PTA calculated with animal and sire models ranged from 0.44 to 0.70 for bucks that had a PTA with a reliability of > or = 30%.