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1.
以沧州市居民饮用水水源大浪淀水库为研究对象,对水体氟化物舍量的TM遥感监测数据进行处理,选出与氟化物含量相关最强的波段组合,构建氟化物含量遥感监测模型.结果表明,所建模型可用于大浪淀水库水体氟化物含量测定.  相似文献   

2.
以沧州大浪淀水库为研究对象,将实测的总氮含量和TM遥感数据反射率进行回归分析处理,构建了总氮含量与各波段多光谱定量遥感模型,并对(TM3+TM4)波段指数模型进行了定量反演,其结果符合水体实际水质分布情况,表明所建模型可应用于该水体总氮含量的监测需要.  相似文献   

3.
以沧州大浪淀水库作为研究对象,将实测的高锰酸钾指数和 TM 多光谱遥感数据反射率进行回归分析处理,构建了高锰酸钾指数多光谱定量遥感模型,并对 TM3/TM5 波段指数模型进行了定量反演,其结果符合水体实际水质分布情况,表明所建模型可应用于该水体高锰酸钾指数的监测.  相似文献   

4.
以沧州大浪淀水库为研究时象,将实测的悬浮物含量和遥感数据进行分析处理,构建了悬浮物含量与TM2+TM3多光谱模型,并对模型进行了反演,其结果符合水体实际水质分布情况,表明所建模型可应用于该水体悬浮物含量的监测需要.  相似文献   

5.
以南京市TM遥感影像为例,利用HOT最优云监测变换方法对遥感影像进行薄云的去除,然后通过分析典型地物在不同波段的光谱特征,引入多波段组合(TM2+TM3)/(TM4+TM5)并辅以单波段(TM5)阈值的方法对南京市的水体信息进行了提取.  相似文献   

6.
为探究海绵城市植物技术设施对重金属及营养盐净化能力,以江心洲南京生态科技岛河道系统为研究对象,对其上下游水体中重金属及营养盐含量进行分析,通过综合污染指数法对上下游重金属风险进行评估,采用冗余分析及Spearman相关系数探究水体环境因素对重金属含量的影响,利用河道区域四种植物技术设施(河岸缓冲带、植被过滤带、生态浮岛、台地式石笼护岸)探究不同植物组合对水体中污染物的净化能力。结果显示,江心洲河道上游重金属的枯水期、丰水期及平水期WQI值分别为1.85、1.74及2.90,分别对应为重金属轻度污染、轻度污染及中度污染。而河道下游重金属的枯水期、丰水期及平水期的WQI值分别为0.18、0.30及0.52,均未存在污染现象。河道上游水体中pH是影响重金属含量的最重要因素,pH与溶解氧(DO)、总氮(TN)、五日化学需氧量(COD5)及总磷(TP)呈正相关。河道下游水体的pH也是影响水中重金属含量最重要的环境因素,其与溶解氧(DO)呈显著正相关。水体中营养盐净化能力大小为河岸缓冲带>植被过滤带>生态浮岛>台地式石笼护岸。相比其它植物组合,乔灌木群落栽植对水体中营养盐净化最具有潜力。  相似文献   

7.
基于I3-与罗丹明B在OP存在下结合成电中性的离子缔合物在360 nm波长处有最大吸收,提出了水样中溶解氧的光度法测定。于待测水样中加入硫酸锰及碱性碘化钾溶液,水中溶解氧与之形成Mn2O3沉淀,加入浓硫酸使与Mn2O3沉淀反应而析出单质碘,在酸性条件下析出的碘与罗丹明B溶液在360 nm波长处有最大吸收,以碘酸钾为基准物,对水样中溶解氧含量进行分光光度法测定。溶解氧浓度在0.002 7~0.686 mg/L范围内符合比尔定律,表观摩尔吸光系数为4.012×104L.cm-1.mol-1,方法的检出限为0.001 0 mg/L。此法对不同来源的水样中溶解氧含量进行测定,所得结果与碘量法及溶解氧测定仪所测得的结果相符合。  相似文献   

8.
针对目前钢铁冶金领域矿相测试方法中反射率测定存在问题,首先,从矿物反射率的定义和矿相显微镜的成像原理出发,结合RGB(红、绿、蓝)和HSI(色调、饱和度、亮度)颜色模型关系,推导出了利用矿物数字显微图像计算反射率的理论数学模型,并通过实验对该模型进行了修正,最后,利用数字图像处理技术计算了各种矿物的含量。本数学模型用于一烧结矿的矿相组成测定,根据所测矿物反射率并结合矿物相关形态结构及其他实验数据,进行综合分析后得出该矿主要由赤铁矿、铁酸钙和硅酸盐组成,这与常规检测方法得到的结果是一致的,说明了该模型用于计  相似文献   

9.
在河北钢铁集团唐钢公司RH生产实绩的基础上,采用多元线性回归的计算方法,建立了RH精炼铝脱氧过程钢水溶解铝含量的预报模型.模型计算结果表明,RH脱碳结束后钢水中的溶解氧含量越高,脱氧后钢水中的溶解铝含量越低;适当高的钢水温度有利于提高钢水溶解铝含量;随钢水脱氧加铝量的提高,钢水中的溶解铝含量逐渐增大.钢水溶解铝含量的实测值基本围绕着预报值波动,模型较好地预测了河北钢铁集团唐钢公司RH精炼铝脱氧后钢水中的溶解铝含量,研究开发的模型可信.  相似文献   

10.
水体中的叶绿素a(Chl-a)浓度是反映水体富营养化的重要指标,针对Landsat数据反演内陆河流Chl-a浓度分辨率低的问题,联合高分一号和哨兵二号遥感影像,以浙江省湖州市吴兴区环城河为研究区域,选取2020年5—9月实测Chl-a浓度和对应日期的遥感影像为数据源,结合半分析模型和APPEL(APProach by Elimination)模型,反演内陆河流Chl-a浓度。通过预处理提取各波段的反射率与实测Chl-a浓度值,对其进行相关性分析,选取80%的实测Chl-a浓度数据与适宜的波段组合为特征变量建立半分析模型,并以对应波段反射率为特征变量建立APPEL模型,利用剩余20%的数据验证半分析模型和APPEL模型反演精度。结果表明,半分析模型反演Chl-a浓度的决定系数(R2)最高达0.66,比APPEL模型高0.50,反演效果优于APPEL模型,更适用于反演小范围流域的Chl-a浓度,而APPEL模型适用于反演大面积流域的Chl-a浓度。  相似文献   

11.
Author made a revision on the theory published by Rihmer and alii in the year 1989. According to this theory the marked regional differences of suicide in Hungary are caused by the different discovery of the "endogen depression" (rate of diagnosed depression). So the lower is the diagnosis of depression the higher is the suicide rate in a given territory. They have seen a negative correlation between the number of working physicians and the suicide rates. Author made a reexamination on a correct database between 1985-1994. He has also made a study using the DSM-III-R diagnostic criteria in four counties of Hungary. His results deny the theory above mentioned. The rank-correlation of the number of GP and the suicide rates in Hungary in years 1985-1994 did not show correlation. So the underdiagnosis of the depressive disorders and the different number of GP are not the cause of the regional differences of suicide in Hungary.  相似文献   

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13.
Bone-marrow chromosomes were examined from 38 mentally and physically retarded and two psychiatric patients who were being treated with a variety of neuropharmacologic drugs. Twenty of these patients used clozapine (Leponex). The clastogenic effects of clozapine in vitro were studied in the lymphocyte cultures of three patients--one free of hematologic disease and two who 6 months earlier had had agranulocytosis attributed to the use of clozapine. The mean frequency of cytogenetic abnormalities in the bone-marrow cells of patients who used clozapine was significantly increased (P less than 0.05). The two patients who had had agranulocytosis had a greater frequency of cytogenetic abnormalities in their cultured lymphocytes in vivo and in vitro than the patient free of hematologic disease. A clone with a 13/14 chromosome translocation was detected in one of the patients. As all patients received a number of drugs during the in vivo and in vitro studies no definite conclusions could be drawn regarding the role played by clozapine in the occurrence of chromosomal abnormalities.  相似文献   

14.
The aim of the present study was to test the ability of the chemotherapeutic agent suramin to inhibit angiogenesis in experimental models in vitro and in vivo. In the culture of rat aortic rings on fibronectin, suramin dose-dependently inhibited vascular cell growth, achieving the maximal effect (mean - 88% versus controls, P < 0.05) at 400 microg/ml. Image analysis showed that suramin could inhibit microvessel sprouting in fibrin from rat aortic rings as evaluated by the ratio between the cellular area and the mean gray value of the sample (sprouting index); suramin at 50 microg/ml significantly reduced the sprouting index from the control value of 0.35+/-0.04 to 0.14+/-0.02 mm2/gray level (P < 0.05). Likewise, the area occupied by cells was 19.2+/-1.8 mm2 as compared with 41.8+/-4.2 mm2 in controls (P < 0.05). In the rat model of neovascularization induced in the cornea by chemical injury, suramin at 1.6 mg/eye per day reduced the length of blood vessels (0.7+/-0.1 mm as compared with 1.5+/-0.1 mm in controls, P < 0.05). In the same model the ratio between the area of blood vessels and the total area of the cornea (area fraction score) was decreased by suramin from 0.19+/-0.02 in controls to 0.03+/-0.003 (P < 0.05). Suramin given i.p. at 30 mg/ kg per day markedly inhibited the neovascularization induced in the rat mesentery by compound 48/80 or conditioned medium from cells secreting the angiogenic protein fibroblast growth factor-3 (FGF-3). The area fraction score in control rats treated with compound 48/80 was 0.31+/-0.03, and this was reduced to 0.07+/-0.01 by suramin (P < 0.05). After i.p. administration of FGF-3 the area fraction score was reduced by suramin from 0.29+/-0.03 to 0.05+/-0.01 (P < 0.05). These results provide evidence that suramin exerts inhibitory effects on angiogenesis in both in vitro and in vivo models.  相似文献   

15.
High plasma renin concentration (PRC) and hematocrit (Ht) were observed in hypertensive rabbits with one renal artery clipped and an intact opposite kidney (Group A), while rather low PRC and Ht in hypertensive ones with one renal artery clipped and the opposite kidney removed (Group B). Plasma volume (PV), blood volume (BV), and packed cell volume (PCV) were estimated in these two types of hypertensive rabbits, and also in sham-operated rabbits (Group C). In Group A, 4 weeks after clipping of a renal artery, PV was decreased and significant inverse correlations were observed between PV and the elevation of blood pressure and between PV and PRC. A significant correlation between PRC and the elevation of blood pressure was also found 4 and 12 weeks after the clipping. PCV was increased until 12 weeks after clipping. In Group B, PV was increased 1 and 4 weeks after clipping, then returned to the initial level. Ht was decreased 1 and 12 weeks, and PCV was decreased 12 weeks after clipping. These results would indicate that a high Ht seen in Group A was partly due to the decreased PV and partly due to the increased PCV, while, in Group B, a low Ht in early stage might be mainly due to the increased PV, but in the late stage, a decreased PCV appeared to play a role to lower Ht. PRC seems to be affected differently by PV in these two types of hypertension.  相似文献   

16.
结合天津铁厂烧结分厂二烧车间烧结过程控制的具体情况,介绍了分散型控制系统在烧结生产上的应用以及数据网上发布的一种方法。  相似文献   

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18.
To examine the possibility of cytokine gene therapy in relation to pancreatic cancer, we evaluated the antitumor effect of human pancreatic carcinoma cells (AsPC-1) which were retrovirally-transduced with several kinds of cytokine genes. These cells were inoculated into BALB/c nude mice and their tumor volumes were assessed. The in vitro growth rate of the transduced cells was not different from that of a parental cell line. Among the transduced cells, human interleukin (IL)-6-transduced AsPC-1 and mouse granulocyte macrophage colony-stimulating factor-transduced AsPC-1 cells showed a significant retardation of tumor growth compared with a parental cell line. In the cases of AsPC-1 cells transduced with the human IL-2 or mouse IL-4 gene, small tumors were generated but thereafter they regressed completely. Histological examinations showed monocytic cell infiltration around the tumors of IL-2- or IL-4-producing cells. These data suggest that secretion of IL-2 or IL-4 from tumor cells can induce an antitumor effect even in the defective condition of mature T cells.  相似文献   

19.
Clinical and bacteriological efficacies of lomefloxacin and ofloxacin were comparatively estimated in the treatment of 104 urologic patients with nonspecific inflammatory diseases and in 36 urologic patients for prophylaxis of inflammatory complications after surgical interventions. The majority of the urinary tract pathogens i.e. Enterobacteriaceae spp. and gramnegative nonfermenting bacteria were highly susceptible to both the fluoroquinolones. The clinical and bacteriological efficacies of lomefloxacin amounted to 94.4 and 80.7 per cent and those of ofloxacin to 92 and 79.2 per cent respectively. The prophylactic use of lomefloxacin and ofloxacin was efficient in 94.7 and 94.1 per cent of the cases respectively. The antibacterial prophylaxis in urologic patients should be applied not only at the period of surgical interventions but also during the early postoperative period.  相似文献   

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