173 resultados para 329-U1369C


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本文从岩石学和地球化学方面对鲁西地区淄博盆地几个岩区的基性脉岩的成因和源区性质进行了探讨。脉岩的K-Ar年龄(72.2~116.3 Ma)表明其为晚中生代(白垩纪)岩浆作用的产物。主量元素显示该脉岩总体属钙碱性系列。微量元素特征表明脉岩为交代富集地幔部分熔融作用的产物,成岩过程可能同时经历了橄榄石、单斜辉石、Ti-Fe氧化物以及少量斜长石的分离结晶作用。Pb同位素组成:^208Pb/^204Pb=36.308~38.329;^207Pb/^204Pb=15.170~15.632;^206Pb/^204Pb=16.658~18.470,可以和下地壳组成相比,暗示成岩过程中存在大量下地壳物质的参与。岩浆在构造上受控于燕山造山带坍塌和沂沭断裂带(郯庐断裂山东段)的活动(左行平移和伸展),但在上升侵位过程中没有遭受地壳物质的混染,且具有大陆边缘弧玄武岩的特性。这暗示岩浆早期鲁西地区存在古大洋板块(苏-鲁洋)的俯冲作用(即古俯冲作用)。

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对赣西北三个地区基性岩脉的地质地球化学特征进行了研究,并初步讨论了基性脉岩的成岩方式和源区性质。基性岩脉包括闪斜煌斑岩,辉绿岩和橄榄录玢岩。微量元素相对富集大离子亲石元素,而亏损高场强元素,具有Nb,Ta和Ti异常。武山煌班岩稀土元素总量高,明显富集轻;益口辉绿岩稀土元素总量低,略微富集轻稀土元素,上高橄榄辉绿玢岩介于两者之间,三者都无明显的铕异常,结合基性脉岩的地球化学分析可知,三者的岩石化学变化受到部分熔融和分离结晶所控制,武山煌斑岩和上高橄榄辉绿玢岩明显发生分离结晶作用,而隘口辉绿岩主要受部分熔融作用影响。其源区可能为与俯冲流体有关的富集地幔,有待于进一步研究。

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本研究选择有代表性的陕西省潼关县(小秦岭地区)采金地区作为研究对象,从环境地球化学的角度出发,研究了该地区由于受采金活动的影响后,大气、水体、土壤以及农作物中总汞和甲基汞的分布,探讨汞在采金地区环境中迁移、转化和富集的环境地球化学行为和规律,并估算了渲关县及全国在过去二十多年里,由混汞法炼金活动向环境释放汞的总量,最后对混汞法采金地区的环境管理提出可行性建一议。通过本论文的详细研究,主要得出以下结论:1.潼关县辖区大气汞的分布呈明显的空间梯度关系,炼金厂密集区大气汞含量明显高于其它地区,距离炼金厂越远,大气汞含量越低。大型炼金厂混汞提金车间内的平均大气汞浓度为18,047ng/m~3,最高达33,080ng/m~3;距离炼金厂密集区较近和较远的居民区的平均大气汞浓度分别为385ng/m~3和77ng/m~3;而一些偏远地区大气汞的平均浓度降至29ng/m~3,受炼金活动影响较 小的黄河沿岸背景区的平均大气汞浓度只有2ng/m~3。通过估算,潼关县炼金矿工汞蒸气的平均摄入量高达72,804~75,268ng/d,而当地非矿工居民(成人)每天的摄入量也有924~4,620ng。2.潼关县内泉水和井水中总汞的平均浓度有329.2ng/L,其中各形态汞的浓度都相对较高,说明金矿地区的汞背景值可能较高,且地下水也可能受到一定程度的汞污染;冷暖两季水样中溶解态汞浓度和暖季的甲基汞浓度要比泉水和井水中的溶解态汞和甲基汞浓度分别高出几倍,其它形态汞则要高出几百倍;水样中的活性汞和溶解态汞浓度表现出极显著的相关关系;冷季水样的活性汞和溶解态汞平均浓度要略高于暖季的水样,而颗粒态汞恰恰相反;两季采集的一些水样中活性汞在溶解态汞中占有较高的比例,但总汞均以颗粒态为主,大多超过50%。3.冷暖两季沉积物中平均总汞浓度分别高达151.1和44.6μg/g,甲基汞平均浓度分别为7.1和3.6ng/g,而暖季沉积物中总汞与甲基汞含量表现出极显著的相关关系;水体颗粒物和沉积物主要来源于炼金厂排出的废渣和尾矿,拥有较高的重金属(Hg、Fe、Mn和Cu)含量,且两者之间体现出一定的继承关系,但颗粒物由于粒径小,表面积大,含有机颗粒多,吸附能力强,所以其中的重金属含量要明显高于沉积物中的重金属含量;颗粒物中汞含量与Fe、Mn、Cu的含量之间均表现出极显著的相关性,而沉积物中汞含量仅与Cu含量之间有一定的相关性,与其它重金属含量的相关性不明显。4.潼关县辖区金矿石中汞的平均含量是69.2ng/g,而炼金尾矿中汞的平均含量竟高达628,4林吮,高出原矿石样中汞平均含量10,000倍,其它重金属(Fe、Mn、Cu)由于受炼金活动影响较小,其含量变化并不十分明显;黄土由于自身的特殊质地和性质,受炼金活动的干扰较小,其中的各重金属含量能够较好的反映其背景含量水平;撞关地区采集的土壤样品中总汞和甲基汞含量均要比黄土中的含量高约50倍,而其它重金属含量与黄土背景值无明显差异;土壤中甲基汞在总汞含量中所占比例较小(分布在0.001%~0.57%之间),说明潼关地区土壤中汞的甲基化水平较低。5.苔鲜样品中的高汞含量反映了采金地区较高的大气汞沉降水平;河流水藻中高含量的总汞和甲基汞体现出汞在生物体内超强的富集作用;潼关县大多数农作物样品中的汞主要来源于大气,且几乎所有样品的汞含量都严重超出国家食用标准,最高超标倍数达到60;农作物中甲基汞含量占总汞的比例在0.12%~12.34%之间波动,其中蔬菜类作物的甲基汞比例要高于粮食作物,而总体来说,作物体内的总汞和甲基汞含量之间表现出一定的负相关关系;通过估算,潼关县居民由于粮食作物(小麦)的食用每天摄入的总汞量高达54,72Ong,要高于当地居民(非矿工)通过呼吸吸入的汞蒸气量,且已超出国际上对人体汞摄入量标准的有关规定。6.潼关县水体、沉积物、土壤以及农作物中的甲基汞含量相对总汞而言,都表现了相对较低的水平,原因可能是受石英脉型金矿地区地质背景的影响,大量存在的Fe、Mn类化合物对离子态汞有着较强的束缚能力,减缓或抑制了甲基化的发生。7.通过混汞法生产黄金的产量和汞释放因子的调研和确定,估算在1980~2003年期间,全国混汞炼金行业向环境释放汞累计达1476.6t,其中约有78%进入大气;而仅潼关县就有116.5t,约占全国的7.9%:目前(1996年以后),由于混汞法工艺的改进,汞的释放量大大降低,全国混汞炼金行业平均每年释放汞约30t,憧关县平均每年有3.9t,约占全国年平均释放量的13%。

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To study the relationship between mental-physical health and coping behavior,job stress and job motivation in medical laboratory scientists and technicians. A cross-section survey was conducted,using the anxiety rating scale(SAS), depression rating scale(SDS), coping behavior rating scale,self-rating subhealth scale,self-rating stress scale,and self-rating job motivation scale among 289 medical laboratory scientists and technicians with analysis of ANOVA and Regression. The study was carried out in three steps:step1 is to analyze the general situation of the mental-physical health.Step 2 is to analyze the features of the main influencial facotors.Step 3 is to study the influence of the relative factors on mental-physical health.The following are the results: 1.The anxiety and depression scores of the medical researchers and technicians were 30±6 and 37±8 respectively,both significantly lower than those of the national norm(34±6 and 42±11 respectively,both P<0.01),which are of significant difference. The depression score of the associate chief technician was 42±7, significantly higher than those of the medical researchers and technicians with any other professional titles (all P<0.05), and the anxiety score of the associate chief technicians was 32±7, significantly higher than that of the research fellows(28±4, P<0.05),with no significant difference to the score of the medical researchers and technicians with other professional titles. The depression score,anxiety score and the subhealth score of the age group of 36~49 were 39±9,31±7 and 32±9 respectively, both higher than that of the age group of 20~35 (36±8,29±6 and 29±7 respectively,both P<0.05),while there is much diference among other age groups. And the subhealth status has nothing to do with marital status,education background and professional titles. 2.The coping behaviors,job stress and motivation of the military medical laboratory scientists and technicians. 1)Coping behaviors:The seeking help score of the associate chief technicians was 2.8±0.5,not significantly different from that of the associate research fellows(2.8±0.5),but significantly lower than those of the medical researchers and technicians with other professional titles(all P<0.01),and whose self-blame score was higher than that of the research fellows,which is of significant difference.The self-blame score and the imagination score of the associate research fellows were 2.0±0.5 and 2.4±0.5 respectively, significantly higher than that of the research fellows(1.6±0.4, 2.1±0.4,both P<0.01). The seeking help score of the females was 3.1±0.5, significantly higher than that of the males(2.9±0.5, both P<0.01),and the solving problem score was 3.4±0.6,significantly lower than the male(3.6±0.7, both P<0.01).There is no any significant difference in coping behaviors among researchers and technicians of different marital status,education background and age groups. 2)Job stress: The score of job stress of the age group of 35~49 and 50~60 were 23±8 and 25±6 respectively,significantly higher than that of the 20~35(21±7,both P<0.05). There is no any significant difference in job stress among researchers and technicians of different marital status,gender,professional titles and education background. 3)The score of meeting personal desire for reputation and interests of the males was 19.6±5.4,significantly higher than that of the females(18.4±5.0, both P<0.05), while there is no significant difference in job motivation among researchers and technicians of different titles,education,age and marital status. 3.The relationship of the mental-physical health of the military medical laboratory scientists and technicians with their coping behaviors,job stress and motivations 1) Coping behaviors:Regression analysis showed that, the best predictors of subhealth were anxiety,depression and escaping (β=-0.40,β=0.23, β=0.14, both P<0.01).the best predictors of anxiety and depression were active coping behaviors and negative coping behaviors (β=-0.40,β=0.40, both P<0.01).The moderate(rational) coping behaviors is the best predictor only of anxiety and of significant difference. 2)job stress : Regression analysis demonstrated that anxiety,depression,job stress 2 and job stress 4 are the best predictor for subhealth;job stress 12 is the best retro-predictor for depression; job stress 3 and 8 are the best predictor for depression;and job stress 2 and 9 are the best predictor for anxiety ,which are of significant difference. 3)Motivation:Regression analysis demonstrated that depression is the best predictor for subhealth while motivation itself doesn't predict subhealth;with respect to the specific contents of motivation,"probing unknown rules and making contributions to the human society "is the best retro-predictor for depression and has nothing to do with anxiety prediction. 4) The combined influences of coping behaviors,job stress and motivations: Regression analysis showed that, the best predictors for subhealth were anxiety,depression and job stress(β=0.41,β=0.24, β=0.19, both P<0.01).the best predictors for anxiety and depression were active coping behaviors and negative coping behaviors (β=-0.40,β=0.40, both P<0.01).The moderate(rational) coping behaviors is the best predictor only for anxiety and of significant difference. CONCLUSIONS: Regression analysis showed that the best predictors for anxiety and depression were active coping behaviors and negative coping behaviors, the best predictors for subhealth were anxiety,depression and job stress.Coping behaviors, job stress and motivations have significant influences on the mental-physical health of the military medical researchers and and technicians. Among them,coping behavior is the most important factor while job stress and motivation follow. Seeking help more often,less self-blame ,imagination and job stress could help release the anxiety, depression and improve the subhealth of the medical researchers and technicians. The findings of this study indicate we should address the physical and mental health of the military laboratory researchers and technicians.