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[en] The present paper deals with the significance of life cycle assessments for the ecological restructuring of market economies. It gives examples of materials flow management and points out the life cycle assessment as a method for valuating products and processes. (orig.)
[de]Im vorliegenden Vortrag wird die Bedeutung von Oekobilanzen bei einem oekologischen Strukturwandel in einer marktwirtschaftlichen Wirtschaftsordnung behandelt. Es werden Beispiele von Stoffstrommanagement erlaeutert und es werden Oekobilanzen als eine Bewertungsmethode von Produkten und Prozessen beschrieben. (orig.)
[en] This study was prompted by the inadequacy of most dispersion quantification techniques to address issues pertaining to scalability, implementation complexity, accuracy/error, uncertainty factors and versatility. Therefore, a method for quantifying dispersion based on gap statistics was developed. A dispersion quantity (D) was formulated from a Gap factor Particle spacing dispersity (PSD 1) and Particle size dispersity (PSD 2) factors. The summation of the factors resulted in the dispersion parameter (D p) which must be equal to one for an ideal or uniformly distributed condition. The state of dispersion increases as D → 100%. The concept was tested with simulated models having uniform dispersion, random dispersion, small aggregate, three large aggregate and one large aggregate were successfully quantified to show 99.34%, 82.42%, 34.17%, 8.95% and 3.65% respectively. For validation of concept, the state of dispersion when samples with (scenario 1) and without (scenario 4) silane treatment were quantified as 32,02% and 7.72% respectively. The concepts were then validated using real microscopy images. This approach is robust, versatile and easy to implement. (paper)
[en] Environmental policy instead of being a constraint is becoming a challenge and a factor of economic development. To reduce pollution it is necessary to find new technologies, that is to say new research, new employment, new industries. Eco-industry is arising, it is a change of behaviour, a new way of management. Environment is a deposit, a mine of technological progress and a source of proceedings diversification with the ability to create jobs
[en] Pollution prevention is the emphasis of the 1990s environmental philosophy. This new environmental era was ushered in when President Bush signed the Pollution Prevention Act in October 1990. This law, with its accompanying philosophy, was in response to the realization that end-of-the-pipe treatment, which frequently changed the media in which a pollutant or waste was discharged, was inadequate to protect the environment and human health. Pollution prevention advocates source reduction, where material substitutions and engineering solutions are sought to reduce the volume and toxicity of waste and pollutants. This proactive approach reduces environmental impacts such as those of former waste sites which have produced environmental legacies that will cost billions of dollars and take decades to remediate. This paper describes pollution prevention philosophy and summarizes regulatory pollution prevention requirements. It describes current regulatory trends in the area of pollution prevention, including voluntary programs and enforcement actions. The Pollution Prevention Act of 1990 is described, and pollution prevention initiatives embodied in other laws, including the Clean Air Act, the Clean Water Act, the Emergency Planning and Community Right-To-Know Act, the Resource Conservation and Recovery Act, and the Toxic Substances Control Act, are discussed. A historical overview of waste minimization initiatives within the Department of Energy is given, and other pollution prevention initiatives that affect federal facilities, such as Executive Order 12780, which mandates recycling and the procurement of recycled materials, are also outlined
[en] Increasing urbanization and industrialization over the world has caused many social and environmental problems, one of which drawing particular concern is the soil pollution and its ecological degradation. In this study, the efficiency of magnetic methods for detecting and discriminating contaminates in the arid and semi-arid regions of northwestern China was investigated. Topsoil samples from six typical cities (i.e. Karamay, Urumqi, Lanzhou, Yinchuan, Shizuishan and Wuhai) were collected and a systematic analysis of their magnetic properties was conducted. Results indicate that the topsoil samples from the six cities were all dominated by coarse low-coercivity magnetite. In addition, the average magnetite contents in the soils from Urumqi and Lanzhou were shown to be much higher than those from Karamay, Yinchuan, Shizuishan and Wuhai, and they also have relatively higher χlf and χfd% when compared with cities in eastern China. Moreover, specific and distinctive soil pollution signals were identified at each sampling site using the combined various magnetic data, reflecting distinct sources. Industrial and traffic-derived pollution was dominant in Urumqi and Lanzhou, in Yinchuan industrial progress was observed to be important with some places affected by vehicle emission, while Karamay, Shizuishan and Wuhai were relatively clean. The magnetic properties of these latter three cities are significantly affected by both anthropogenic pollution and local parent materials from the nearby Gobi desert. The differences in magnetic properties of topsoil samples affected by mixed industrial and simplex traffic emissions are not obvious, but significant differences exist in samples affected by simplex industrial/vehicle emissions and domestic pollution. The combined magnetic analyses thus provide a sensitive and powerful tool for classifying samples according to likely sources, and may even provide a valuable diagnostic tool for discriminating among different cities. -- Highlights: • Magnetic properties of topsoil were compared in six cities in northwestern China. • Urban soil in northwestern China contains more MD/PSD magnetite than eastern China. • Industrial and traffic-derived pollution was dominant in Urumqi and Lanzhou. • Lithogenic magnetite is one of the dominant ferrimagnets in soils nearby desert. -- Use of magnetic approach to estimate and contrast soil pollution in northwestern China, and discriminate the contributions of different pollution sources
[en] The goal of this work is to validate the use of the Exradin W1 plastic scintillation detector (PSD) to measure profiles and output factors from Gamma Knife Perfexion collimators in a Lucy phantom. The Exradin W1 PSD has a small-volume, near-water-equivalent, energy-independent sensitive element. Output measurements were performed for all 3 collimators (4 mm, 8 mm, and 16 mm) of the Gamma Knife Perfexion system, and these measurements were compared to measurements made with an A16 ion chamber and an EBT3 film and to the nominal values. We showed that a configuration in which the focus or ‘shot’ moves while the detector remains fixed is essentially equivalent to a configuration in which the focus is fixed while the detector moves. A Lucy phantom containing a PSD was moved in small steps to acquire profiles in all three dimensions. EBT3 film was inserted in the Lucy phantom and exposed to a single shot for each collimator. The relative values for output factors measured with the PSD were 1.000, 0.892, and 0.795, for the 16 mm, 8 mm, and 4 mm collimators, respectively. The values measured with EBT3 film were 1.000, 0.881, and 0.793, and the values measured with the A16 ion chamber were 1.000, 0.883, and 0.727. The nominal output factors for the Gamma Knife Perfexion are 1.000, 0.900, and 0.814, respectively. There was excellent agreement between all profiles measured with the PSD and EBT3 as well as with the treatment planning system data provided by the vendor. In light of our results, the Exradin W1 PSD is well suited for beam quality assurance of a Gamma Knife Perfexion irradiator. (paper)
[en] A novel method for detecting the in-plane movement of MEMS devices has been presented, in which a scanning grating structure has been adopted. One end of the grating is directly connected to the movable platform under test, while the other end is fixed to a substrate, both by a suspending beam. Due to this structure design, any in-plane movement of the platform will be finally translated into grating rotation. When a laser beam is incident onto the grating, the direction of diffracted light as well as its spot position on a photosensitive device (PSD) will be changed accordingly due to the grating rotation. From the output of the PSD, the movement amplitude can be finally determined. With this novel sensing mechanism, not only static and dynamic movements, but also the transient structure response have been experimentally demonstrated.
[en] The atrocities inflicted upon humanity in the name of progress there should be an end to it as discussed at length in the title of Enforcement of Legislation to control the Environmental Pollution, the smoke emitting vehicles plying on the road side, polluted water allover the country, uncontrolled smoke of factories, kiln, steel mills thermal power station and enormous activities uncontrolled in the presence of Environmental Laws, what else we need to accomplish the same, it is due to lack of education that we yet to get to show some improvements in this aspect, but who will suffer? Non but The coming generation. Spreading pollution in the name of progress; Industries, factories, and machines, in excess; Black smoke and the refuse, they process Contaminate the rivers and the land's bareness; Threatens the laws of nature, they transgress; Undernourished children suffering from poverty; Perished food and their bodies scrawny; Asking the world with heir eyes teary; Why the deprivation and their futures foggy. Hear, O' embryo my pieces of ad ice; For every great deed you ought to pay a price, Strive for restoring the peace of nature; Struggle against the odds like a strong creature; Loving the nature and singing His song; God is with lose who are steadfast and strong. (author)
[en] Superconducting qubits can act as noise sensors because their decoherence times under certain pulse sequences can be linked to the system's noise power spectral density (PSD). These sequences also set the observable frequency range of the PSD. The PSD during free evolution of the qubit can be obtained with a dynamical decoupling (CPMG-) pulse sequence, which renders the qubit only susceptible to noise within a narrow frequency band. The PSD during driven evolution is measured with a so-called spin-locking sequence, during which only noise at the Rabi frequency can affect the qubit. Both protocols were successfully tested on a flux qubit by Bylander 1 and Yan 2. In this work, we apply these two protocols to a tunable concentric transmon 3, overcome the challenge of the transmon's low anharmonicity by using DRAG pulses and compare the PSDs of free and driven evolution. Our results show a clear 1/f dependence in both cases, as well as a white spectrum at frequencies above 1 MHz during free evolution. The successful application of these protocols to a transmon permits magnetic noise sensing with such a qubit in future experiments.
[en] 'Fundamentals of Environmental Engineering' contains the technical and legal bases for the force environmental areas water supply and waste water disposal, clean air, waste avoidance and waste disposal, as well as noise protection in compact form. Particular scope was allowed for the description of the linkages between the individual environmental areas - for instance, waste combustion and clean air, waste deposition at landfills and treatment of leachate, residual products from successful water and air pollution control measures. For all those who have to familiarize themselves with the complex subject of 'environmental engineering' while in training or during continuing education this book offers a broad approach to the essential general, technical and legal bases. (orig.)
[de]'Basiswissen Umwelttechnik' enthaelt in kompakter Form die technischen und rechtlichen Grundlagen der vier Umweltbereiche Wasserver- und -entsorgung, Luftreinhaltung, Abfallvermeidung und -entsorgung sowie Schallschutz. Besonderer Wert wurde auf die Darstellung der inhaltlichen Zusammenhaenge zwischen den einzelnen Umweltbereichen gelegt - z.B. Muellverbrennung und Luftreinhaltung, Abfalldeponierung und Sickerwasserbehandlung, Reststoffe aus erfolgreichen Wasser- und Luftreinhaltemassnahmen. Das Buch ermoeglicht allen, die sich bei der Aus- oder Fortbildung in die komplexe Materie 'Umwelttechnik' einarbeiten muessen, einen fundierten Einstieg in die wesentlichen allgemeinen, technischen und rechtlichen Grundlagen. (orig.)