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1

Status, invasiveness and environmental threats of three tropical American invasive weeds (Parthenium hysterophorus L., Ageratum conyzoides L., Lantana camara L.) in India  

British Library Electronic Table of Contents (United Kingdom)

Invasive weeds have threatened the integrity of ecosystems throughout the world. They affect not only the species diversity of native areas but also their biological integrity. In India, a number of invasive exotic weeds have been reported but some viz. Parthenium hysterophorus, Lantana camara and Ageratum conyzoides, especially those from tropical America are troublesome and have caused adverse ecological, economic and social impact. These weeds can be seen growing in different landscapes but are luxuriantly localized in unattended forests and cultivated areas. Parthenium hysterophorus (Asteraceae, commonly known as congress grass) is perhaps the most troublesome and noxious weed of urban and rural India. Besides rapidly colonizing areas replacing the native vegetation, it is also known t...

2006-01-01

2

Chemical transformations of organic matter during the composting of wood industry wastes (residues); Transformacoes quimicas da materia organica durante a compostagem de residuos da industria madeireira  

Energy Technology Data Exchange (ETDEWEB)

Composting of sawdust and paper mill sludge, using a 'Kneer' process reactor, was studied in an attempt to elaborate upon organic matter transformation during the process and to define parameters to measure the compost maturity level. Temperature, electron paramagnetic resonance data, ash and C, H, N and S contents, and a spectroscopic method using ultraviolet-visible (UV-VIS) for alkaline (pH = 8.5) and solid samples was used to study the maturity of the compost samples. These parameters were measured in 6 humic acids extracted from the compost samples during 29 days. The results of this work show that the 'Kneer' process is efficient in transforming ligno-celulitic residues in a short time (29 days), into an organic fertilizer material with application perspectives (author)

2004-06-01

3

Indirect heating of natural gas using vapor chambers; Aquecimento indireto de gas natural com uso de camaras de vapor  

Energy Technology Data Exchange (ETDEWEB)

Operation safety and reliability are major guidelines in the design of city-gate units. Conventional natural gas heaters operate by a indirect mechanism, where liquid water is used to transfer heat by natural convection between the combustion chamber and the natural gas coil. In this work, the concept of vapor chamber is evaluated as an indirect gas heater. In a vapor chamber, liquid water is in contact with the heat source, and vaporizes. The vapor condenses in contact with the heat sink. A reduced scale model was built and tested in order to compare these two heating concepts where the combustion chamber was replaced by electrical cartridge heaters. This engineering model can operate either as a conventional heater or as a vapor chamber. The comparison between the concepts was done by inducing a controlled power to the cartridges and by measuring the resulting temperature distributions. In the novel design, the heat exchanger efficiency increases, and the thermal inertia decreases, ...

2005-07-01

4

Design, construction and testing of a radon experimental chamber; Diseno, construccion y pruebas de una camara experimental de radon  

Energy Technology Data Exchange (ETDEWEB)

To carry out studies on the radon behavior under controlled and stable conditions it was designed and constructed a system that consists of two parts: a container of mineral rich in Uranium and an experimentation chamber with radon united one to the other one by a step valve. The container of uranium mineral approximately contains 800 gr of uranium with a law of 0.28%; the radon gas emanated by the mineral is contained tightly by the container. When the valve opens up the radon gas it spreads to the radon experimental chamber; this contains 3 accesses that allow to install different types of detectors. The versatility of the system is exemplified with two experiments: 1. With the radon experimental chamber and an associated spectroscopic system, the radon and two of its decay products are identified. 2. The design of the system allows to couple the mineral container to other experimental geometries to demonstrate this fact it was coupled and proved a new automatic exchanger system of ...

1991-10-15

5

Calibration methods of plane-parallel ionization chambers used in electron dosimetry; Metodos de calibracao de camaras de ionizacao de placas paralelas para dosimetria de feixes de eletrons  

Energy Technology Data Exchange (ETDEWEB)

The use of linear accelerators in radiotherapy is of great importance in Medicine, and according to international recommendations the electron beam dosimetry has to be performed using plane-parallel ionization chambers, previously calibrated in standard gamma radiation fields at accredited laboratories. In this work, calibration methods of plane-parallel ionization chambers used in dosimetry procedures of high energy electron beams of clinical accelerators were presented, tested and intercompared. The experiments were carried out using gamma radiation beams of {sup 60} Co at the Calibration Laboratory of Clinical Dosemeters at IPEN and electron beams od 4 to 16 MeV at the Radiotherapy Department of Hospital Israelita Albert Einstein, Sao Paulo. A method was chosen to be established at IPEN. Proposals of the calibration procedure, calibration certificate and data sheets are presented. (author)

1999-07-01

6

Effects of holmium laser on dental structure in vivo: thermal evaluation and histological analysis on pulpal tissue; Efeitos in vivo do laser de holmio em estrutura dental: monitoracao termica e analise histologica do tecido pulpar  

Energy Technology Data Exchange (ETDEWEB)

Previous in vitro studies have demonstrated that Ho:YLF laser is capable of inducing physical and chemical changes on dental surfaces treated for caries prevention. The temperature in the pulp chamber was in vitro evaluated to as a function of the power and frequency of the laser irradiation. The purpose of this work is to verify the occurrence of pulp inflammation after Ho:YLF laser irradiation using different parameters in rabbits' teeth. The premolars and molars of ten rabbits (NZB) were divided in two groups according to the irradiation energy values of a Ho:YLF laser prototype operating at 2.065{mu}m wave length, frequency of O,5Hz and pulse length of 250{mu}s. An group A teeth were irradiated with using ten pulses of 334mJ/pulse of a Ho:YLF laser prototype operating at O.5Hz, and group B, with 512mJ/pulse. Animals were killed by transcardiac perfusion and the samples were prepared for histopathological analysis. The in vitro temperature monitoring revealed an increase of ...

2001-07-01

7

The carrying out process of Kyoto Protocol in Italy. Methods, scenarios and policy evaluation; Il processo di attuazione del Protocollo di Kyoto in Italia. Metodi, scenari e valutazione di politiche e misure  

Energy Technology Data Exchange (ETDEWEB)

This paper reports some technical contributes related to the Kyoto Protocol and its application in Italian decision making policy. [Italian] Il presente volume raccoglie una decina di contributi tecnici originariamente preparati o commissionati dall'ENEA, Ente Nazionale per le Nuove Tecnologie, l'Energia e l'Ambiente, in vista della Conferenza Nazionale Energia e Ambiente. Questa fotografia di una situazione in rapida evoluzione e' stata preparata da esperti del settore che contribuiscono a redigere il materiale tecnico di base utilizzato dai negoziatori nazionali durante le trattative internazionali e dai responsabili nazionali per avviare il processo di presa di decisioni in materia.

2000-07-01

8

Ionospheric response to the phenomena occurring below and above it: a summary  

Energy Technology Data Exchange (ETDEWEB)

Some of well known F{sub 2} layer anomalies might have their origin in lower atmosphere and some have extra terrestrial sources. It has been suggested that the phenomena occurring below the ionosphere such as thunderstorms, lightning/sprites, volcanic eruptions and earthquakes and above the phenomena like corona mass ejection, solar flares and extra terrestrial events may produce F{sub 2} layer signatures. In the present paper we have tried to summarize the effect of some phenomena occurring below the ionosphere like thunderstorms, lightning/sprites and seismic activity and the phenomena such as solar flares which occur above the ionosphere, on the ionospheric electron and ion temperatures. The paper also discusses possibilities. The ionospheric electron and ion temperatures were measured by the RrPAa payload aboard the Iindian SRrOSS-C2 satellite. The normal day's ion and electron temperatures have been compared to the temperatures recorded during the disturbed day. The ...

2009-01-15

9

Determination of volatiles produced during radiation processing in food and medicinal herbs; Determinacao de volateis produzidos durante o processamento por radiacao em ervas alimenticias e medicinais  

Energy Technology Data Exchange (ETDEWEB)

In order to protect food from pathogenic microorganisms as well as to increase its shelf life while keeping sensorial properties (e.g. odor and taste), once the latter are one of the main properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. The aim of the present study was to analyze volatile formation from Co irradiation of Laurus Cinnamomum, Piper Nigrum, Origanum Vulgare and Myristica Fragans. Possible changes on the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties in order to allow better application of irradiation technology. l he samples have been irradiated in plastic packages by making use of a {sup 60}Co Gamma irradiator. Irradiation doses of 0, 5, 10, 15, 20 and 25kGy have been tested. For the analysis of the samples, SPME has been applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation has promoted mostly ...

2008-07-01

10

The angiogram sign in pulmonary atelectasis studied with helical Computed Tomography. Incidence and value; Il segno dell'angiogramma nelle atelettasie polmonari studiate con Tomografia Computerizzata spirale. Incidenza e validita' semeiologica  

Energy Technology Data Exchange (ETDEWEB)

In this issue it has been investigated the yield of Helical CT in the study of lung vessels, the incidence of the angiogram sign and its actual value. July 1997 to December 1998, were studied 30 cases of pulmonary collapse of different origin. It was found 15 cases of passive collapse (10 from pleural effusion, 2 from diaphragmatic compression, 2 from traumatic pneumothorax, and 1 from isthmic aortic aneurysm), 12 cases of obstructive collapse (9 from bronchogenic carcinoma, 1 from mucoid obstruction, 1 from ilar lymphadenopathy, and 1 from mediastinal cancer), 2 cases of adhesive collapse and 1 case of round atelectasis. All the examinations were performed with the Helical technique during nonionic iodinated contrast agent injection (bolus, 300-350 mg/mL); it was used an automatic injector set at 2-3 mL/s. It was studied the images for the angiogram sign, that is hyperdense bands, usually longer than 2 cm, through the collapsed lung, which correspond to normal pulmonary vascular ...

1999-12-01

11

Fifteen years of seismic monitoring at the Las Tres Virgenes, BCS, geothermal field; Quince anos de monitoreo sismico en el campo geotermico de Las Tres Virgenes, BCS  

Energy Technology Data Exchange (ETDEWEB)

Seismic monitoring at the Las Tres Virgenes, BCS, geothermal field started in 1992 with an analog station of vertical components detecting a large number of earthquakes of varying magnitudes. In February 1993, a seismic network was installed, composed of six digital stations DR-2000-with S-6000 and S-5000 sensors and three registration channels (N-S, E-W and vertical). This was the basis for the development of a program to correct arrival-time data for P and S waves due to instrument drift. From January to April 1994 and May to August 1995, based on the 170 seismic events recorded, a velocity model was proposed. From December 1995 to July 1996, seismic data were processed and interpreted, and zones of occurrence were determined for events according to magnitude and the predominant noise in the field. From September 2003 to December 2004, 10 seismic stations (permanent and temporary) were installed and monitored and it was concluded the most active fault system was El Volcan. From ...

2009-07-15