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41.
在数字视频处理中经常需要考虑斑点去除问题。运动矢量估计是斑点检测和去除的基本步骤。在斑点存在的区域,运动向量的估计可能会出现较大的偏差。大多数算法只通过空间上运动矢量的相关性来进行修正。本文根据空间上和时间上图像灰度和运动矢量相关的特点,并考虑块分级之间运动矢量的相关性,提出了一种运动估计的修正方法。仿真结果显示,本文的方法是有效的。  相似文献   
42.
水体腐殖质危害及去除的研究进展   总被引:3,自引:0,他引:3  
水体中腐殖质是消毒过程中产生三氯甲烷类(THMs)物质的前体,其中腐植酸和富里酸又是水体腐殖质的主要组成部分。本文阐述了水体腐殖质的形成与基本性质,分析了由其引起的危害,并结合国内外目前对水体腐殖质去除的研究现状,评述了水体腐殖质的主要去除技术与方法。  相似文献   
43.
凤眼莲对Cu2 、Pb2 、Cd2 等离子的耐受性为:Cd>Pb>Cu.短期累积去除率为Pb>Cu>Cd;表明凤眼莲在快速高效去除低浓度含铅废水、治理含镉废水和作为铜污染废水的指示性植物等方面有良好的应用前景.  相似文献   
44.
小球藻生物吸附废水中铜的研究   总被引:2,自引:0,他引:2  
以小球藻作为生物吸附剂,去除水溶液中微量Cu~(2+),研究结果表明小球藻对Cu~(2+)的生物吸附主要经历了快速的吸附和缓慢的吸收两个步骤:pH值是影响Cu~(2+)生物吸附的一个重要影响因素,最佳pH值在6~8之间;离子强度对Cu~(2+)的吸附有一定的抑制作用;小球藻对Cu~(2+)的生物吸附符合Freundlich等温方程。  相似文献   
45.
Mercury pollution in the Three Gorges Reservoir area of P. R. China merits special attention. We investigated into the current situation in the Chongqing part of the Reservoir area, identified the pollution sources and proposed some suggestions for the remediation and prevention of mercury pollution in this area. Atmospheric mercury in Chongqing was mainly from coal burning and releases of mercury-containing products such as various types of lights and fever thermometers. Urban drainage in Chongqing and Changshou, and runoffs from the high mercury background area in the lower reaches of the Wujiang River contributed most of the mercury in the water of the Yangtze River. A majority of the blame should be laid on mercury and gold mining in the Wujiang valley. We suggested foresting sloping lands to relieve soil erosion and prevent mercury-bearing soil from running into rivers, educational activities to discourage use of mercury-containing products and improved infrastructure to collect mercury-containing wastes for reducing mercury releases, more facilities for treating wastewater and solid waste to accommodate increased requirements of discharge, and growing selected perennial plants in mercury-contaminated land to absorb the mercury in soil. We also suggested concerted operation of a dedicated water-quality monitoring system, reinforced legislation and an effective administrative mechanism to ensure lasting efforts are invested in curbing mercury releases and restoring mercury contaminated land and water in the Reservoir area.  相似文献   
46.
研究了对羧基苯偶氮硫代若丹宁 (CPATR)与汞的显色反应,在pH为3.5的醋酸-醋酸钠缓冲介质中,吐温-80存在下, CPATR与汞反应生成2:1稳定络合物,该络合物可被Waters Sep-Pak C18小柱固相萃取,用氮-氮二甲基甲酰胺(DMF)洗脱后用光度法测定,在洗脱液介质中,λmax=535 nm,体系摩尔吸光系数达8.70×103 m2/mol. 汞的质量浓度在0.05~4.0 mg/L内符合比尔定律. 该方法可用于烟草及其添加剂中汞含量的测定,结果满意.  相似文献   
47.
外丹铅汞论自东汉魏伯阳撰《参同契》后,便在中国炼丹术理论中居主导地位,“铅”、“汞”亦因此被炼丹家称之为“五金之主”和“灵而最神”的药物。然而,在一千多年的道教炼丹术历史中,无论是炼丹术士还是学者,他们对铅汞何以具有如此神奇作用的真正原因,却大多愦愦不知。本文一依《参同契》之内容与历史原貌,将文句阐释置于当时的社会大背景中去把握,从而对《参同契》以“水基”、“金精”和“两孔穴法”的多寡及有无来决定药物珍贵与否的理论,作出了贴近原意的释读,为正确把握中国教炼丹术铅汞论的本质,提供了一个可能的解释系统。  相似文献   
48.
Sulfide-containing waste streams are generated by a number of industries. It is emitted into the environment as dis- solved sulfide (S2- and HS-) in wastewaters and as H2S in waste gases. Due to its corrosive nature, biological hydrogen sulfide removal processes are being investigated to overcome the chemical and disposal costs associated with existing chemically based removal processes. The nitrogen and sulfur metabolism interacts at various levels of the wastewater treatment process. Hence, the sulfur cycle offers possibilities to integrate nitrogen removal in the treatment process, which needs to be further optimized by appropriate design of the reactor configuration, optimization of performance parameters, retention of biomass and optimization of biomass growth. The present paper reviews the biotechnological advances to remove sulfides from various environments.  相似文献   
49.
We report the adsorption of phosphate and discuss the mechanisms of phosphate removal from aqueous solution by burst furnace slag (BFS) and steel furnace slag (SFS). The results show that the adsorption of phosphate on the slag was rapid and the majority of adsorption was completed in 5-10 min. The adsorption capacity of phosphate by the slag was reduced dramatically by acid treatment. The relative contribution of adsorption to the total removal of phosphate was 26%-28%. Phosphate adsorption on BFS and SFS follows the Freundlich isotherm, with the related constants of k 6.372 and 1/n 1.739 for BFS, and of k 1.705 and 1/n 1.718 for SFS. The pH and Ca^2+ concentration were decreased with the addition of phosphate, suggesting the formation of calcium phosphate precipitation. At pH 2.93 and 6.93, phosphate was desorbed by about 36%-43% and 9%-11%, respectively. These results indicate that the P adsorption on the slag is not completely reversible and that the bond between the slag particles and adsorbed phosphate is strong. The X-ray diffraction (XRD) patterns of BFS and SFS before and after phosphate adsorption verify the formation of phosphate salts (CaHPO4·2H2O) after adsorption process. We conclude that the removal of phosphate by BFS and SFS is related to the formation of phosphate calcium precipitation and the adsorption on hydroxylated oxides. The results show that BFS and SFS removed phosphate nearly 100%, indicating they are promising adsorbents for the phosphate removal in wastewater treatment and pollution control.  相似文献   
50.
本文目的是总结微创颅内血肿清除术的护理体会;方法是回顾分析我院附属医院2000年4月至今86例微创颅内血肿清除术的术前准备、手术配合、术后护理;结果是除13例极重症脑出血患者死亡外,其余人恢复满意。结论是良好的术前准备和手术配合,术后保持呼吸道通畅,严格控制血压,做好引流管护理、高热护理和预防压疮的护理,对成功抢救脑出血患者起了十分重要的作用。  相似文献   
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