SRI跳泵后的故障处理

本文从闭式水的系统功能出发,对SRI水泵跳泵后的风险及处理思路进行分析,以利于相关的故障处理及机组状态控制。     

GCT系统在机组瞬态下的响应及故障处理

本文介绍了GCT系统的基本功能,并结合其工作原理,对一些瞬态工况进行了分析,重点论述了在满功率停机不停堆工况下,GCT121VV未正常开启时调节系统的响应过程。并从机组控制的角度对操纵员的如何进行故障处理进行了探讨。     

桑园智能水肥一体化系统的开发与应用

正为了提高桑园水、肥利用率,减少水资源浪费和肥料的使用量,国家蚕桑产业技术体系桑树生产管理机械化岗位团队重点对桑园智能水肥一体化系统进行了研究。该团队利用PLC、HMI、无线传输技术和现代灌溉技术,开发了一套可通过手机/电脑远程遥控的桑园智能水肥一体化系统,主要由主控制系统、砂石过滤器、肥料桶、管道、泵、电机等组成,能够一次施氮、磷、钾和中微量元素等4种营养肥料,额定扬程为55 m,流量0.5～2 m3,一套系统可以管理6.7 hm2桑园     

配置两台100%电动给水泵机组满负荷切换试验研究

介绍了国外135MW循环流化床机组配置两台100%电动给水泵,在机组满负荷时模拟一台泵发生故障跳闸,另一台泵安全成功启动的切换试验,并在试验后对相关逻辑和参数进行了优化。     

一种采用主回路精确流量校准核仪表系统方法的研究

核电厂核仪表系统功率量程中子注量率变化率是反应堆保护系统的重要参数,对该参数的计算校准,既可以保证在发生弹棒和落棒事故时正常执行停堆功能,又可以在寿期初和寿期末发生甩负荷至厂用电运行工况时避免停堆而影响核电厂的经济性。当前核电厂,核仪表系统功率量程中子注量率变化率引入的主回路平均温度信号和主泵转速信号进行校准。本文着重介绍一种采用精确的反应堆冷却剂系统主回路流量来校准中子注量率变化率的方法,对其进行研究与探讨,以达到提高功率量程中子注量率变化率的校准精度的目的。     

小型饲料加工机组试验结果分析

<正> 1986年,农牧渔业部农机鉴定总站和饲料粮油加工机械鉴定站,对全国部分小型饲料加工机组进行了评选和推广鉴定。现将测试结果初步分析如下。一、性能方面 1.小时生产率参加试验的机组额定小时生产率为300～2500kg,实测结果为485.3～2532.3kg/h,实测生产率都超过额定生产率,有的超过1倍多如湖南省临湘县机械厂的9SJ—300A机组,额定小时生产率为300kg,实测达 733.5kg/h;四川畜牧机械厂的YH—500型机组,额定小时生产率为500kg,实测达1313.3kg/h。这说明有些机组的生产潜力很大,只要使用得当,一般生产率可提高50％以上。 2.千瓦小时产量在22台机组中,最高为     

凝结水泵无法盘车故障分析与处理

某核电站凝结水系统的3台凝结水泵在安装阶段出现泵轴无法盘车缺陷。通过长达三个月的分析处理,目前3台凝泵运行正常。本文主要结合凝结水泵的结构和装配,以及水润滑轴承特点进行分析研究,明确导致凝结水泵无法盘车的根本原因,并为今后同类型水润滑轴承立式泵盘车故障处理提供参考。     

变频电动柱塞泵作为水压试验泵的运行应用

某核电厂的水压试验泵需执行三个功能,每个功能需要的压力不同,且最高压力需要达到24MPa,而流量基本相同,所以需要采用特殊结构的泵。本文从变频电动柱塞泵的基本原理、结构、运行方式来阐述其如何实现为中压安注箱充水、供主泵应急轴封水和水压试验功能。通过对三种运行工况的功能试验验证其是否满足工况运行要求。对其试验结果进行分析可得:当泵出口压力从0-24MPa范围内变化时,流量为5.9-6.1m~3/h,满足充水和供主泵应急轴封水运行要求;通过变频器调节电机频率可以达到0.4MPa/min的升压过程,也可实现保压在24MPa,从而满足水压试验运行要求。     

变电站站用电源低压备自投装置回路的改进

在供电企业快速发展的过程中,变电站站用电源低压备自投装置的应用也越来越广泛,对提高供电系统供电的可靠性有着极大的作用,尤其是在某一变压器出现故障的情况下,可以通过备自投装置将其电源切换到另一台变压器上,进一步提高供电的可靠性,而且,备自投装置是未来电力企业发展中需要持续改进的重要设备,对供电企业的长期发展有着深远的影响.     

浅谈水煤浆气化炉炉砖磨损原因分析

<正>1.项目简介内蒙古伊泰煤制油有限公司(以下简称伊泰煤制油公司)一期16万吨/年煤制油项目于2009年3月建成投产。目前,伊泰煤制油公司气化系统由3台处理量为1000t煤/d气化炉组成,2开1备。原料煤以当地长焰煤为原料,由两套棒磨机(Φ3.4×5.8m)生产线组成。化     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.     

Mechanism of Action of Probiotic Function of Lactobacilli

乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.     

Evaluation of serum concentrations of biomarkers of skeletal metabolism and results of radiography as indicators of severity of osteochondrosis in foals

OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis.