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1.
常规生化处理很难使垃圾渗滤液达到市政污水纳管排放标准,或无法稳定排放,必须进行深度处理。本文探索了微波诱导催化用于渗滤液的深度处理,以铁层柱蒙脱石作催化剂,微波辐照下深度处理垃圾渗滤液。结果表明,对初始COD浓度为1100~1300 mg/L的垃圾渗滤液,以铁层柱蒙脱石作为催化剂,在微波功率600 W,辐照时间30 s条件下,经微波诱导催化处理后,COD去除率达到39%。铁层柱蒙脱石催化剂以"卡房"型介孔结构为主,均匀的介孔结构有利于微波诱导催化。  相似文献   

2.
In the strdy of the source material of granites ,it is found that cosmic dust can be used as one of the indicators for identifying the genetic types of granites.It is suggested that granites can be grouped into two genetic types, dust-barren granite and dust-containing granite, corresponding to I-type and S-type respectively as defined by Chappell et al.  相似文献   

3.
Long term characteristics of solar and galactic cosmic rays, as revealed by the study of their nuclear effects in lunar, meteoritic and terrestrial samples are summarised. The data so far available on radioisotopes, noble gases and tracks, though limited, are consistent with nearly constant fluxes and composition during different epochs over billions of years; one exception is14C activity in the earths atmosphere over the past few hundred years, suggesting a variation in the solar activity. Other small or brief variations, which cannot be ruled out as yet, require better estimation of depth and size dependence of nuclear effects in rocks before they can be attributed to cosmic rays.  相似文献   

4.
利用主被动微波数据联合反演土壤水分   总被引:5,自引:1,他引:5  
在黑河中游干旱区水文试验的基础上,以临泽站为研究区域,探讨主被动微波数据联合反演土壤水分的方法。针对ALOS/PALSAR数据,使用AIEM理论模型计算地表的同极化后向散射系数,Oh半经验模型描述交叉极化散射特征,通过对大量后向散射模拟数据的分析,建立裸露地表粗糙度计算模型;利用模拟数据分析地表辐射亮温随土壤水分和粗糙度的变化规律,在此基础上构建NN模型结合粗糙度计算结果和辐射计飞行数据反演研究区域的土壤水分。地面同步测量数据的验证结果表明,该方法充分发挥了主被动微波数据各自的优势,同时避免了主被动协同过程中的尺度问题,为流域尺度的土壤水分监测提供了一种新的有效途径。  相似文献   

5.
海泡石是一种纤维状含水的富镁硅酸盐黏土矿,其中的稀土元素含量在1×10~(-7)~1×10~(-5)之间,目前还没有建立海泡石中稀土元素的国家标准分析方法。测定岩石中的稀土元素主要是采用电感耦合等离子体质谱法(ICP-MS),样品前处理一般采用封闭溶矿和碱熔,但这两种处理方法耗时较长,效率不高。本文通过比较硝酸-氢氟酸-过氧化氢、硝酸-氢氟酸、硝酸-过氧化氢三种样品前处理方法,确定使用硝酸-氢氟酸溶矿,然后进行微波消解同时赶去氢氟酸,避免氢氟酸与稀土元素生成难溶的氟化物,再采用ICP-MS法测定15种稀土元素的含量。由于海泡石中的镁含量较高,为降低基体效应,以~(103)Rh和~(185)Re作内标补偿基体效应和校正灵敏度漂移,各元素测定值的准确性显著提高,回收率为91. 2%~110. 9%,检出限为0. 002~0. 011μg/L,精密度≤2. 79%。本方法与封闭酸溶ICP-MS法的分析结果吻合较好,且用酸量少(7 mL),溶矿效率高(1 h),检出限更低。  相似文献   

6.
以水镁石为原料,与盐酸反应制得氯化镁,然后将氯化镁和氨水碱溶液在室温下反应得到氢氧化镁,再通过水热处理制备出了超细、高纯的氢氧化镁颗粒,通过利用X射线衍射仪(XRD)和扫描电子显微镜(SEM)对所制得氢氧化镁颗粒的晶相、形貌和颗粒尺寸进行了表征。实验结果表明水热处理温度、填充度和搅拌速度对氢氧化镁晶体的晶相和颗粒尺寸有显著的影响,升高温度有助于改善颗粒的晶形和分散性、并减小颗粒的尺寸,较高的填充度有利于六方片状颗粒的生成,当填充度为40%,搅拌速度为400 r/min,水热处理温度为150℃时,制备出了半径约100~250 nm,厚度为10~100 nm,晶形完整,分散性好、大小均一的六方片状超细、高纯的氢氧化镁颗粒。  相似文献   

7.
The applied context of this paper is the exploration for petroleum resources, like petroleum accumulations in different deposits, where the most promising deposits are likely to be drilled first, based on some size indicators, so-called creaming. The paper explores creaming models in the context of sampling with probabilities in proportion to size, for which a lognormal size distribution has nice analytical features. It departs from the traditional paradigm in petroleum resource assessment. Instead of conceiving a finite population being depleted over time in a decaying fashion with respect to size, the situation is studied within the framework of independent observations (infinite population) and an exploration maturity-dependent creaming factor. The theoretical and practical consequences for inference on the parent population and the probabilities and expectations linked to future discoveries are studied. The theory applies to the issue of remaining sizes of petroleum resources to be found within different future discovery horizons on the mature part of the Norwegian Continental Shelf. The aim is to obtain reasonable and useful predictions, and not to provide the best possible explanation of the exploratory behavior itself.  相似文献   

8.
Natural disasters have a considerable effect in human, infrastructure and economy. In the case of a, e.g., catastrophic earthquake that happens and affects the urban environment, immediate and efficient actions are required that ensure the minimization of the damage and loss of human lives. Local and national authorities should respond in order to meet the above objective. Nowadays, one of the most appropriate tools for this purpose is the web-based geographic information systems (GIS). Such a system, named SyNaRMa (Information System for Natural Risk Management in the Mediterranean), has been developed in the frame of an INTERREG IIIB ArchiMED project (2006?C2008). The present paper aims at addressing the role of the SyNaRMa system as a tool for facilitating disaster management. It is argued that the development of a web-based GIS can assist disaster management agencies to improve the quality of their decision making and increase efficiency and effectiveness in all levels of disaster management activities. This research is primarily based on the findings of the abovementioned project that resulted in the development of an information system for natural risk management in the Mediterranean that can facilitate sharing, access and usage of spatial data in disaster management, i.e., preparedness, response and recovery activities.  相似文献   

9.
塔里木盆地白垩纪灰褐色含油砂岩中发现的宇宙尘为硅质宇宙尘,该宇宙尘粘附于伊/蒙混层粘土矿物表面,近于理想球体,直径为6um,具镶嵌结构。这一发现在我国白垩系尚属首次。在化学成份上该宇宙尘与已报导的宇宙尘相似,对已发现的宇宙尘氧化物成份的研究表明,地球物质中TiO2/SiO2,TiO2/FeO,FeO/SiO2分别为0.01,0.17,0.1。  相似文献   

10.
刘文彬  伏万军 《沉积学报》1994,12(2):101-104
塔里木盆地白垩纪灰褐色含油砂岩中发现的宇宙尘为硅质宇宙尘,该宇宙尘粘附于伊/蒙混层粘土矿物表面,近于理想球体,直径为6μm,具镶嵌结构?这一发现在我国白垩系尚属首次?在化学成份上该宇宙尘与已报导的宇宙尘相似,对已发现的宇宙尘氧化物成份的研究表明,地球物质中TiO2/SiO2,TiO2/FeO,FeO/SiO2分别为0.01,0.17,0.1?  相似文献   

11.
Political ecologists working in many other parts of the world are now heading north, or simply going global, posing a series of important questions related to theory, methodology, politics, and policy along the way. This special issue, contains papers originally delivered at a conference held at Rutgers University in 2003 that addressed this phenomenon. The papers collected offer case studies that reveal the First World as subject to a host of processes that can be insightfully understood via a political ecology perspective. First, globalized production and consumption regimes have created new linkages that demand synoptic analyses of often far-flung research sites. Second, the painful coincidence of deindustrialization and a radical restructuring of agricultural credit and price support systems have devastated North American and European heartlands, effectively producing “Third World” conditions in many depressed rural areas. Third, migration streams originating in Latin America, Africa and many parts of Asia have brought sizable Third World populations into the spatial heart of capitalism. Fourth, the belated recognition of some indigenous claims to resources, especially in Canada, and fierce opposition to others, have reopened questions of (internal) colonial domination. Finally, we see the burgeoning First World political ecology literature as the culmination of what Louise Fortmann has called “the long intellectual journey home” for many scholars who originally carried out research on/in the Third World. All of these factors have combined to help political ecologists discover suitable analytical terrain in the First World.  相似文献   

12.
Kuzmenko  I. V. 《Astronomy Reports》2021,65(12):1254-1264
Astronomy Reports - Several solar events with different types of negative microwave bursts have been studied using data from different spectral ranges. The total radio flux data obtained at the...  相似文献   

13.
铜精矿、镍精矿和锌精矿是金属硫化矿物,且为大宗进口商品,准确分析其中的稀散元素有利于矿物的综合利用。这类矿物中的稀散元素含量极低,各元素性质各异,尤其Ge和Se在湿法消解中由于挥发损失而无法准确定值,很难进行多种元素的同时测定,传统的方法需要通过预先分离富集,采用不同的仪器进行测定。本文以铜精矿、锌精矿和镍精矿为代表性硫化矿,采用微波消解对样品进行密闭前处理,电感耦合等离子体质谱法(ICP-MS)测定稀散元素含量,实现了多种元素的同时测定。条件实验表明在同时检测镓、锗、硒、镉、铟、碲、镧、铊的过程中,总固溶量、内标、质谱干扰消除的条件对三种金属硫化矿均一致,只是前处理过程中用酸的选择有些差异。硝酸-盐酸-氢氟酸-过氧化氢体系适合于测定镍精矿和锌精矿中的Ga、Ge、Se、Cd、In、Te、La、Tl和铜精矿中的Ga、Ge、Se、Cd、In、La、Tl,各元素的回收率在85.5%~116.6%之间;王水溶样法更适合测定铜精矿中的Te。  相似文献   

14.
应用电感耦合等离子体质谱法(ICP-MS)分析岩石和土壤样品中稀土元素的含量,取样量可低至数毫克级,但200目样品粒度要求分析取样100mg才能保证代表性,导致ICP-MS灵敏度高、取样量小的优势难以得到充分发挥。本文研究了研磨方式、研磨时间、物料比对超细粒度土壤和岩石样品制备的影响,结果表明采用乙醇作为分散剂进行湿法球磨,200目粒度的土壤、岩石样品分别研磨10min和15min,土壤样品的物料比采用物料7g、研磨球500个、分散剂45mL,岩石样品的物料比选取物料5g、研磨球500个、分散剂45mL,细化程度最佳。在此条件下制备的超细粒度土壤标准物质GBW07404、GBW07447的粒径分布D_(95)可低至7.51μm、7.05μm,超细粒度岩石标准物质GBW07104、GBW07121的D_(95)可低至8.42μm、8.30μm。在硝酸-氢氟酸-过氧化氢酸溶体系中微波消解处理超细粒度岩石标准物质GBW07104,取样量减少至5mg,总用酸量减少至0.25mL,消解时间降低为25min,稀土元素的测定值与认定值基本一致,相对标准偏差在1.64%~5.21%之间。该方法用于分析其他超细粒度标准物质(GBW07404、GBW07447和GBW07121)中的稀土元素,相对误差为0.17%~6.60%,满足《地质矿产实验室测试质量管理规范》的一级标准。  相似文献   

15.
青藏高原积雪深度和雪水当量的被动微波遥感反演   总被引:30,自引:13,他引:30  
车涛  李新  高峰 《冰川冻土》2004,26(3):363-368
利用1993年1月份的SSM/I亮度温度数据反演了青藏高原的雪水当量,首先使用被动微波SSM/I数据19和37GHz的水平极化数据来反演雪深,根据积雪时间的函数来计算实时的雪密度,由雪的深度和密度计算出雪水当量.最后,利用SSM/I数据的19和37GHz的垂直极化亮度温度梯度对计算出的雪水当量进行回归分析,得到了利用SSM/I数据直接反演雪水当量的算法.  相似文献   

16.
分析地质样品中稀土元素的含量,现有的方法都受到基体干扰和共存元素干扰,电感耦合等离子体质谱(ICP-MS)已在痕量元素分析中得到广泛应用,通过条件优化可准确测定稀土元素。本文建立了ICP-MS同时测定铁矿石中钇镧铈镨钕钐铕钆铽镝钬铒铥镱镥15个稀土元素的方法,样品用盐酸、硝酸和氢氟酸高温密闭消解,消解完全后转移定容,在线加入103Rh、115In、185Re内标液进行测定,方法回收率为95%~104%,精密度(RSD)≤3.5%。对12个国家24个代表性主产区进口的铁矿石样品进行检测,分析其稀土元素的配分模式特征为右倾型轻稀土富集,现阶段的进口铁矿粉多为多产区复合配矿。本方法较其他传统方法大幅降低能耗,提高了分析效率,初步探讨的稀土元素丰度特征可为研究主产区铁矿石的矿床成因、提高我国烧结球团矿的加工工艺提供依据。  相似文献   

17.
18.
<正> 20世纪90年代的十年时间里,世界上共发现了76个储量超过5×10~8bbl 油当量(可采)的大型油气田。其中,大多数的油田位于墨西哥湾、墨西哥、巴西、北非、西非以及中东地区;而巨型气田主要集中在南美以及沿里海穿中东和亚洲到奥大利亚的一条狭长地带。在这些巨型油气田的发现中,在五个方面起了重要作用:(1)近距离勘探(重钻、扩边、更深的油藏、走向带上探边井);(2)深层目标;(3)新生界深水新区;(4)天然气勘探的加强;(5)技术进步。  相似文献   

19.
随着稀土的应用越来越广泛,开发稀土元素的快速在线检测技术已日趋成为行业发展的需求。本文以微波等离子体炬(MPT)为离子源,以四极杆质谱仪(QMS)作为质量分析器建立了一种快速、直接检测水样中稀土元素的质谱检测方法,并将其应用于分析稀土矿样中的多种稀土元素。研究表明,应用MPT-QMS测定水样中的钇、镧、铈、钕、铕五种稀土元素,检出限(LOD)可达11.0~60.5μg/L,测定范围为50~1000μg/L。当分析固体稀土矿样时,样品经酸溶处理后通过气动雾化形成气溶胶,再进行冷却干燥,气溶胶由MPT的中心管道进入等离子体中,产生稀土元素复合离子,再引入QMS中进行分析,即可以定量地测定矿样中稀土元素的含量。同一样品用电感耦合等离子体质谱(ICP-MS)进行对比实验,两者的检测结果在数量级上接近,证明了MPTQMS方法在半定量的意义下是准确、可靠的,因而这种快速的检测方法可发展成为水体中金属元素的现场分析方法,应用于环境水、生活水质量在线监测等领域。  相似文献   

20.
Pasargadae complex had been the main center of Persian history during the Achaemenian period (560–330 bc), registered as one of the world heritage sites by UNESCO in 2004. This research is an attempt to recognize the natural setting and landscape of Pasargadae during the Achaemenian period, in Iran. The method is based on the application of a multi-layer technique. Collected data by fieldwork, especially in geology, hydrology, and hydrogeology, along with the analysis of aerial data and satellite information provided the baseline information for preparing historic and environmental layers and have made it possible to recognize a natural lakelet in the this area. The results show that the geometry of lakelet together with the ancient river of Pasargadae had been the main elements that formed the character of the site; they were also important in the locations of buildings in the Pasargadae complex.  相似文献   

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