储罐清洗是石油化工企业,尤其是油库和炼厂等企业的一项经常性的工作,主要有人工清罐和机械清罐两种方法,人工清罐方法由于存在巨大的安全隐患、能源浪费、环境污染等问题,正逐步被淘汰。目前采用的机械清罐方法大都是基于击碎溶解原理...储罐清洗是石油化工企业,尤其是油库和炼厂等企业的一项经常性的工作,主要有人工清罐和机械清罐两种方法,人工清罐方法由于存在巨大的安全隐患、能源浪费、环境污染等问题,正逐步被淘汰。目前采用的机械清罐方法大都是基于击碎溶解原理的COW方法,该法依靠在罐顶多点式均布的清洗机的射流来击碎、溶解、回收罐内积存的沉积物,从而达到消除罐底沉积物的目的,与人工清罐法相比,采用C O W机械清罐法具有一定的优点,但仍存在着清洗前临时管线安装工作量大、人员上下罐调节清洗机频繁、需要向罐内持续注入惰性气体等弊端,当采用该方法,对大型储罐,尤其是容积在5万m3以上的储罐进行清洗时,清洗工期一般都需两个月以上。本文提出了一种基于大流量扰动技术的新型储罐机械清洗方法,旨在解决大型原油储罐的安全、高效清洗难题,与现有清洗方法相比,具有无需注氮、安全性高、施工效率高、人工劳动强度低等显著优点。展开更多
Objective: To investigate the specificity of the effects of electroacupuncture (EA) at different acupoints on gastric functional activity and gastric blood flow after colorectal distension (CRD) in the rat. Methods: F...Objective: To investigate the specificity of the effects of electroacupuncture (EA) at different acupoints on gastric functional activity and gastric blood flow after colorectal distension (CRD) in the rat. Methods: Fifty Wistar rats were randomly divided into 5 groups: a control group, a Zusanli group, a non-point group, a Taichong group and a Neiguan group. Rats were anesthetized after 18 h of fasting, and a rat model of nociceptive blood pressure elevation and abnormal electrogastrogram (EGG) and gastric tension (GT) was prepared by gasbag-induced CRD. EA was given bilaterally, and its effects on gastric blood flow (GBF) of the arcus vasculosi of the greater omentum, blood pressure, EGG fast wave properties, and gastric smooth muscle tension (GT) were quantified. Results: CRD induced an increase in blood pressure that was significantly inhibited by EA at all points (all P<0.05), and the inhibitory effects were greater in the Zusanli and Neiguan groups compared to the non-point group (both P<0.05). CRD also caused reductions in GT and GBF, and in the amplitude, frequency and duration of EGG waves (all P<0.05). These effects were also reversed by EA. The effects of EA on EGG wave amplitude, GT, and GBF were superior in the Zusanli group compared to the Taichong group, Neiguan group, and the non-point group. Conclusion: EA significantly counteracted CRD-induced changes in blood pressure, GBF, EGG, and GT. The effects of stimulation at Zusanli (ST 36) were significantly greater compared to other points, indicating relative specificity of this acupoint.展开更多
文摘储罐清洗是石油化工企业,尤其是油库和炼厂等企业的一项经常性的工作,主要有人工清罐和机械清罐两种方法,人工清罐方法由于存在巨大的安全隐患、能源浪费、环境污染等问题,正逐步被淘汰。目前采用的机械清罐方法大都是基于击碎溶解原理的COW方法,该法依靠在罐顶多点式均布的清洗机的射流来击碎、溶解、回收罐内积存的沉积物,从而达到消除罐底沉积物的目的,与人工清罐法相比,采用C O W机械清罐法具有一定的优点,但仍存在着清洗前临时管线安装工作量大、人员上下罐调节清洗机频繁、需要向罐内持续注入惰性气体等弊端,当采用该方法,对大型储罐,尤其是容积在5万m3以上的储罐进行清洗时,清洗工期一般都需两个月以上。本文提出了一种基于大流量扰动技术的新型储罐机械清洗方法,旨在解决大型原油储罐的安全、高效清洗难题,与现有清洗方法相比,具有无需注氮、安全性高、施工效率高、人工劳动强度低等显著优点。
基金supported by TCM Item of National Key Basic Study (2005CB523306, 2006CB504506 2007CB512505)the National Natural Science Foundation of China (30973796, 90709031)
文摘Objective: To investigate the specificity of the effects of electroacupuncture (EA) at different acupoints on gastric functional activity and gastric blood flow after colorectal distension (CRD) in the rat. Methods: Fifty Wistar rats were randomly divided into 5 groups: a control group, a Zusanli group, a non-point group, a Taichong group and a Neiguan group. Rats were anesthetized after 18 h of fasting, and a rat model of nociceptive blood pressure elevation and abnormal electrogastrogram (EGG) and gastric tension (GT) was prepared by gasbag-induced CRD. EA was given bilaterally, and its effects on gastric blood flow (GBF) of the arcus vasculosi of the greater omentum, blood pressure, EGG fast wave properties, and gastric smooth muscle tension (GT) were quantified. Results: CRD induced an increase in blood pressure that was significantly inhibited by EA at all points (all P<0.05), and the inhibitory effects were greater in the Zusanli and Neiguan groups compared to the non-point group (both P<0.05). CRD also caused reductions in GT and GBF, and in the amplitude, frequency and duration of EGG waves (all P<0.05). These effects were also reversed by EA. The effects of EA on EGG wave amplitude, GT, and GBF were superior in the Zusanli group compared to the Taichong group, Neiguan group, and the non-point group. Conclusion: EA significantly counteracted CRD-induced changes in blood pressure, GBF, EGG, and GT. The effects of stimulation at Zusanli (ST 36) were significantly greater compared to other points, indicating relative specificity of this acupoint.
