攀钢3#高炉富氧大喷煤操作浅析

通过分析攀钢３＃高炉富氧大喷煤后的炉况特征及其原因，了冶炼钒钛磁铁高炉进行富氧大喷煤只有以精料煤为基础，并采用合理的高炉操作制度，才能取得理想的经济效益。     

高炉富氧喷煤后的焦比变化

通过对高炉富氧喷煤的能量计算，研究了高炉富氧喷煤后的焦比变化，讨论了富氧喷煤对焦比的影响，富氧喷煤后焦比降低量及煤粉燃烧率对及富氧喷煤效果的影响。     

高炉“氧煤”辨析

1 问题的提出 当今是高炉发展富氧大喷煤(氧煤过程)的良机,但是在技术上如何去发展富氧大喷煤却有二种不同的做法:一是技术上努力创新,即发展氧煤直接燃烧;二是老技术延伸,即把氧加入鼓风中。2 发展富氧大喷煤的技术经济背景 1996年的喷煤会议结束了,这次会议有一个重要信息就是国家正在酝酿用更有力的     

天铁高炉富氧喷煤效果分析

1 引言 1992年,天铁高炉煤比达到87kg/t,个别高炉已超过100kg/t。为了进一步提高煤比,多喷煤,少用焦,立足于现有焦炉的生产能力进行炼铁生产,我们开始设想进行高炉富氧喷煤。1994年,天铁炼钢投入生产,其制氧系统为高炉应用炼钢余氧进行富氧喷煤创造了条件。后经安装相应的管道阀门,5号高炉于1995年3月开始利用炼钢余氧进行富氧喷煤试验。采用富氧喷煤后,高炉煤比提高     

富氧大喷煤高炉操作线研究

高炉富氧大喷煤时,必须考虑煤气中的氢元素、煤的预热及挥发分的分解热。作者对不喷煤时高炉操作线的计算和绘制方法进行修正,推导出富氧大喷煤时高炉操作线的计算公式。应用该公式可预测富氧大喷煤条件下高炉内煤气成分、煤气量、热量分布和化学反应等的变化,以便控制这些变化带来的影响,保证高炉顺行。     

鞍钢高炉富氧喷吹烟煤优化试验研究

鞍钢２号高炉经一年多富氧喷吹烟煤优化冶炼试验，提出了原燃料质量，优化喷煤工艺，设备，喷煤品种和操作手段，取得显著效果。高炉连续半年以上富氧２４．７１％，１００％喷吹烟煤１６１ｋｇ／ｔ，煤焦转换比０．８８。掌握了富氧喷吹烟煤的冶炼特征和操作规律，并转入大工业生产。     

高炉富氧鼓风的现状及机前供氧

阐述了高炉生产采用富氧大喷煤的必要性，国内高炉富氧鼓风的现状，以及机前富氧的优点和应采取的安全措施。     

昆钢高炉富氧喷煤初步实践

昆钢高炉１９９１年６月开始喷煤，１９９６年９月首次在２＃高炉实现富氧喷煤，经初步实践，增产效果明显，１％富氧率增产达６．０７％，目前受原料条件等限制，进展较慢。随综合料场建成，原料条件和高炉顺行情况改善，富氧喷煤可望取得新进展。     

高炉富氧喷煤预测

用高炉热状态优化和预测模型,对高炉富氧喷煤进行预测表明,富氧鼓风是实现大喷煤量并维持高炉最佳热状态的必要条件。富氧和喷煤二者具有良好的互补性。富氧后不一定需要相应提高风口前理论燃烧温度,不然高炉区域热平衡将遭到破坏,出现下部区域热量过剩和上部区域热量不足问题。     

炉料金属化率对富氧喷煤高炉冶炼过程的影响

根据高炉物料平衡和区域热平衡理论，参照高炉富氧喷煤和使用金属化炉料的冶炼结果，计算了炉料金属化率对富氧喷煤率、焦比和产量的影响。结果表明：①炉料金属化率达到４０％后，高炉不能富氧操作；②较低的炉料金属化率与富氧喷煤相结合，能够获得更大的喷煤比和更高的产量；③使用金属化率较高的炉料，能够比富氧喷煤达到更低的焦比。     

3200m~3高炉喷吹系统工艺优化与改进

针对邯宝炼铁厂高炉喷吹系统存在的诸多问题,对喷煤工艺进行了改进和操作优化,彻底解决了喷吹启动困难的问题,减小了喷吹脉动现象,提高了装煤速度和喷吹能力,增强了喷煤保障性,满足了高炉喷煤量的要求,最大喷煤比已达150 kg/t以上。     

Drug distribution in the vitreous humor of the human eye: the effects of intravitreal injection position and volume

PURPOSE: The purpose of this study was to determine how the position and volume of an intravitreal injection affect the distribution and elimination of drug from the vitreous humor. METHODS: A mathematical model that had been developed and used previously to study drug distribution in the vitreous humor of the rabbit eye was modified to match the physiology of the human eye. Fluorescein and fluorescein glucuronide were used as the model compounds for these studies. Four extreme injection locations were considered: a central injection, an injection displaced towards the retina, an injection displaced towards the lens, and an injection displaced toward the hyaloid membrane. Injections containing an equal mass of drug dissolved in volumes of either 15 microL or 100 microL were compared. RESULTS: The location of an intravitreal injection was found to have a substantial effect on elimination and distribution in the vitreous. Peak concentrations at different vitreous locations varied by over three orders of magnitude, depending on the injection location. The mean concentration of drug remaining in the vitreous 24 hours after the intravitreal injection varied by up to a factor of 3.8, depending on the injection location. Changing the volume of the injection from 15 microL to 100 microL dampened the effects of the initial injection location; however, meant concentrations at 24 hours still varied by up to a factor of 2.5. CONCLUSIONS: Careful control of the conditions of an intravitreal injection could reduce treatment variability, improve bioavailability, and reduce the possibility of retinal toxicity.     

The effect of injection speed on the pain of lidocaine infiltration

OBJECTIVE: To determine whether reducing the speed of injection is effective in reducing injection pain for buffered and unbuffered lidocaine solutions. METHODS: A prospective, single-blind, randomized, crossover, laboratory study was performed. Adult volunteers were recruited from ED staff at an urban teaching hospital to serve as subjects. Twenty-nine subjects each received 4 1-mL injections into the dorsum of the hands. Each subject received fast and slow injections of buffered and unbuffered lidocaine. Subjects rated the pain of each injection on a 100-mm visual analog scale (VAS). Mean pain scores for each intervention were compared using analysis of variance. RESULTS: The mean pain VAS score for fast injection of buffered lidocaine was 14.1 mm. For slow buffered injection, the mean pain score was 11.4 mm (p = 0.98). For unbuffered lidocaine, the means were 28.7 mm for fast injection and 22.2 mm for slow injection (p = 0.40). CONCLUSIONS: Reducing injection speed did not produce a statistically significant change in injection pain for either buffered or unbuffered solutions.     

Effect of metoclopramide, ranitidine, and droperidol on the lower sphincter of the esophagus. Experimental study on the opossum (Didelphis albiventris)

Electromanometric measures of the gastroesophageal junction were performed in 20 adult, male and female, anesthetised opossums. The electromanometric examinations were performed according the intermitent pull through technique. The research was divided in four groups, according to the drug to be analysed: group 1 (20 animals) IM injection of physiological solution (control group); group 2 (20 animals) IM injection of metoclopramide; group 3 (20 animals) IM injection of ranitidine; group 4 (20 animals) IM injection of droperidol. Electromanometry was done 15 minutes before the drug injection, just after the injection and 15, 30, 45 and 60 minutes after the injection. In each one of the moments the pressure of the lower esophageal sphincter (LES-mmHg) was analysed. Considering LES pressure the results observed were: in group 1 it was not observed any significative alteration after IM injection of physiologic solution; in group 2 it was observed significative pressure increase, 15 minutes after metoclopramide IM injection; in group 3 it was observed pressure increase, being significative at 15 and 30 minutes after IM injection; in group 4 it was observed significative increase in LES pressure in every moment, 15 minutes after droperidol IM injection.     

高炉喷煤控制系统中喷吹率算法的实现

介绍了炼铁高炉喷煤控制系统设备及生产情况,对影响称重信号及喷吹率计算的干扰因素进行了详细分析,并提出解决方法。喷吹率计算程序中设计了移位寄存器程序块,在保证喷吹率的计算精度的同时又兼顾实时性。经过四年的应用证明,喷吹率计算稳定,使用效果良好。     

Stability and compatibility of granisetron hydrochloride in i.v. solutions and oral liquids and during simulated Y-site injection with selected drugs

The stability and compatibility of granisetron hydrochloride in common i.v. fluids and oral liquids and during simulated Y-site injection with selected drugs were studied. One milliliter of solution containing granisetron 1 mg (as the hydrochloride salt) was added to 50 mL of 5% dextrose injection, 5% dextrose and 0.9% sodium chloride injection, 5% dextrose and 0.45% sodium chloride injection, or 0.9% sodium chloride injection in polyvinyl chloride (PVC) bags and to 5 mL of 5% dextrose injection, 0.9% sodium chloride injection, or bacteriostatic water for injection in polypropylene syringes and stored at room temperature (20 degrees C) for 24 hours. One milliliter of the granisetron hydrochloride injection was added to 50 mL of apple juice, orange juice, cola, or an electrolyte replacement solution and stored for 60 minutes at room temperature. Twenty-nine drugs were mixed with the granisetron hydrochloride injection in 0.9% sodium chloride injection in volumes simulating Y-site injection and stored at room temperature. Finally, dexamethasone sodium phosphate injection 0.5 mL and 1 mL of the granisetron hydrochloride injection were added to 50 mL of 0.9% sodium chloride injection in a PVC bag and stored for 60 minutes. Drug concentrations were determined by high-performance liquid chromatography, and color, clarity, and pH were evaluated. Granisetron hydrochloride was stable in and compatible with all the i.v. solutions and oral liquids. Neither granisetron nor any of the drugs it was tested with during simulated Y-site injection showed any physical changes except for a slight Tyndall effect in the granisetron hydrochloride-doxorubicin hydrochloride combination; all the drugs retained at least 96% of initial concentrations. Granisetron and dexamethasone sodium phosphate were stable and compatible in the admixture. Granisetron 1 mg (as the hydrochloride salt) was stable for 24 hours in four i.v. infusion fluids in PVC bags and in 5% dextrose injection, 0.9% sodium chloride injection, and bacteriostatic water for injection in polypropylene syringes; for 1 hour in four oral liquids; for 4 hours in the presence of each of 29 drugs during simulated Y-site injection; and for 1 hour when mixed with dexamethasone sodium phosphate in 0.9% sodium chloride injection in a PVC bag.     

The influence of the bolus injection rate of propofol on its cardiovascular effects and peak blood concentrations in sheep

The influence of the bolus injection rate of propofol on its cardiovascular effects has not been extensively studied. We therefore examined the influence of the injection rate of i.v. bolus doses of propofol on its acute cardiovascular effects and peak blood concentrations in seven chronically instrumented sheep. Each received i.v. propofol (200 mg) over 2 min (slow injection) and 0.5 min (rapid injection) on separate occasions in random order. The rapid injection was associated with more profound decreases in mean arterial blood pressure than slow injection (35.7% vs 23.7% maximal reductions from baseline, respectively; P = 0.02). There were no significant differences between the injection rates for peak reductions in myocardial contractility, increases in heart rate, or degree of respiratory depression. Concurrently, the rapid injections were associated with significantly higher arterial (26.9 vs 11.9 mg/L) propofol concentrations in a manner consistent with indicator dilution principles. There were no differences in the peak coronary sinus concentrations between the injection rates. We conclude that the rapid injection of propofol in the context of the induction of anesthesia produced significantly higher peak arterial propofol concentrations and suggest that it is these higher concentrations that produced relatively greater reductions in arterial blood pressure from rapid injections. Implications: Propofol is injected into a vein to initiate anesthesia. It can cause a rapid decrease in blood pressure, which may be dangerous to the patient. We examined the effect of rapid and slow injection rates of propofol in sheep and found that rapid injection caused a greater decrease in blood pressure. This was because rapid injection caused higher concentrations of propofol in the blood immediately after the injection. We believe that if the same processes occur in humans, there may be little advantage in injecting propofol rapidly.     

复合喷射与单喷镁脱硫效果的分析比较

马钢一炼钢现用两种不同的喷吹脱硫工艺,一种是复合喷吹（石灰＋镁粉）,另一种是单喷颗粒镁。通过从原理、工艺、设备、原材料要求、实际喷吹效果及经济性等方面进行比较分析,得出各自的特点和优势,用以更好地指导脱硫生产实践。     

太钢1800m~3高炉喷煤系统设计及运行

太钢3号高炉喷煤系统采用三罐并列、喷吹主管加分配器的喷吹形式,喷吹装置最大喷吹能力为煤比250kg/t。主要特点：三罐并列喷吹计量准确;采用浓相喷吹,实现了对氮气的回收;使用两段式喷枪、一键式全自动操作等。喷吹系统2007年8月投产,平均煤比180kg/t以上,个别月份达到200kg/t。经过两年的生产实践证明,该系统设计合理,一直处于良好的运行状态。     

Evaluation of the radiosensitizing effects of RK28 intravenous, intraarterial, and intratumoral injections on the rabbit VX2 tumor system

PURPOSE: To evaluate the differences in the radiosensitizing effects of intravenous (i.v.) injection, intraarterial (i.a.) injection, and intratumoral (i.t.) injections of the hypoxic cell radiosensitizer RK28 ([1-(4'-hydroxy-2'-butenoxy)methyl-2-nitroimidazole], a 2-nitroimidazole with an acyclic sugar analogue substituted at the N-1 position of the imidazole ring) using an animal experimental system. METHODS AND MATERIALS: Rabbit VX2 tumors, which were implanted in the muscle of left hind legs and grown to 3 cm in diameter, were treated with RK28 (80 mg/kg x b.wt.) before 15 Gy of local x-ray irradiation. The auricular vein and the left saphenous artery were used for systemic injection and regional injection, respectively. For i.t. injection, a 21-gauge needle with three lateral holes was positioned in the central area of the tumor. Tumor regression was precisely evaluated by computed tomograpy (CT), and survival time was also studied. Using high-performance liquid chromatography (HPLC), pharmacokinetic studies for RK28 and its seven major metabolites were performed in tumor and serum at 0, 10, 20, 30, and 60 min after drug injection was completed. RESULTS: Radiosensitizing effects of RK28 were considered present after i.a. injection (p < 0.05) and i.t. injection (p < 0.05) after analyzing tumor volumes on day 21 after treatment. Increased survival was not observed in any group with RK28 injection compared with survival in the group treated by x-ray irradiation alone. Pharmacokinetic studies showed the average concentration of RK28 in the tumor during x-ray irradiation was 1.3 times higher after i.a. injection and 3.5 times higher after i.t. injection than that after i.v. injection. The time modifying factor50 (TMF50: ratio of time for tumor to decrease by 50%, radiation alone vs. radiation plus drug) was calculated to be 1.5 after i.v. injection, 1.7 after i.a. injection, and 2.3 after i.t. injection. The values of TMF50 correlated to the average concentrations of RK28 in the tumor. As to metabolites of RK28, beta-glucuronated compound and cysteine conjugate were highly detected. The concentrations of cysteine conjugate were higher in the tumor than in serum via i.v. injection. CONCLUSIONS: Radiosensitizing effects of RK28 were observed on the rabbit VX-2 tumor system after i.a. or i.t. injection. Pharmacokinetic studies proved that radiosensitizing effects depended on the concentration in the tumor, though the administration routes were different. Combined forms with nonprotein thiols were detected. However, survival benefits were not obtained by RK28. For clinical applications of RK28, i.a. or i.t. injection could facilitate better local control of cancer.