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921.
922.
Katsuyuki Nakano Ryosuke Aoki Hiroshi Yagita Nobuhiko Narita 《The International Journal of Life Cycle Assessment》2007,12(5):289-298
Background, Aim and Scope The Home Appliance Recycling Law (hereunder referred to as the Law) for used cathode ray tube (CRT) TVs, air conditioners,
refrigerators and washing machines was enacted in April 2001 in Japan. The Law requires that retailers reclaim, and manufacturers
and importers recycle such home appliances. Consumers are required to pay collection and recycling fees incurred in disposing
of any of the four home appliances. Home appliances must, as a general rule, be managed in accordance with the Law. In reality,
other routes exist, such as via local authorities, scrap processors, illegal dumping and exporting. At about the time the
Law was enacted, the refrigerant used for air conditioners and refrigerators was replaced by more environmentally friendly
substances such as isobutene. Local authorities had the responsibility of disposing of the appliances of households before
the enactment of the Law. It was general practice for local authorities to dispose of home appliances in landfills after breaking
them up and recovering valuable resources such as iron, copper and aluminum. Although they made efforts to recover refrigerant
fluorocarbons, there were not required to do so.
Materials and Methods This study analyzed the material flow resulting from the Law and other processing flows to quantify the global warming effect
caused by home appliance recycling using the life cycle assessment (LCA) method. To evaluate the Law and to develop policy
planning, the challenges of future efforts will be considered using time series data. For these reasons, we have assessed
the Project Scenario, which corresponded to the present reality; the Baseline Scenario, which assumed that measures such as
the Law were not implemented after 2000, and the Ideal Scenario, where all used products were recycled as prescribed by the
Law. The environmental impacts for each scenario were estimated using value, which was obtained from multiplying the amount
of reproduction and waste treatment by each inventory data.
Results It is estimated that emission reductions of 4.7E+4 t CO2e, subtracted the Project Scenario from the Baseline Scenario, were reduced for TVs in 2001 through recycling. The impact
from recycling glass from cathode ray tube (CRT) televisions is significant. An improvement of 2.3E+4 t CO2e could be anticipated by upgrading to the Ideal Scenario in 2001.
It was estimated that there was a reduction of 9.2E+5 t CO2e in 2001 for air conditioners. Although the effect of the recovery for refrigerants contributed greatly, some fluorocarbons
that are still discharged have had a considerable impact on greenhouse gas emissions. Hypothetically, a reduction of 3.2E+6
t CO2e could be anticipated with the Ideal Scenario in 2001.
A reduction of 2.6E+6 t CO2e was achieved for refrigerators in 2001. Although a further reduction can be anticipated through the Ideal Scenario, there
will not be much difference with the Project Scenario by 2010.
It was estimated that 3.8E+4 t CO2e were reduced for washing machines in 2001. Only a small improvement can be expected through the Ideal Scenario.
Discussion Since many assumptions were used in this study, a sensitivity analysis was carried out in order to grasp their impact. The
findings of the sensitivity analysis are that the uncertainties are large, but the number of the greenhouse gas (GHG) reductions
is still clear except for the difference between the Project Scenario and the Ideal Scenario for TVs. This analysis gives
authenticity to the findings.
Conclusions Establishing a system for liquid crystal display and plasma display panel TVs is desirable because the absolute amount of
used LCD/PDP TVs will rapidly increase as the usage of CRT TVs rapidly decreases from 2007.
With regard to refrigerant recovery from air conditioners, a significant decrease in GHG emissions has been recorded. There
is, however, still ample room for improvement. It will be necessary to switch to refrigerants with low global warming potentials
(GWPs) or work more on improving the recovery rate in the future. Alternatives and recovery of fluorocarbons from refrigerators
contributed greatly to GHG reductions. The GHG emissions from refrigerator recycling will be minimal whether used refrigerator
will be processed legally or not because most used refrigerators will contain natural refrigerants in the near future. The
improvement for washing machines was low because it was assumed that their main constituent steel has been previously recycled,
and that the plastic recycling rate will not change significantly in the future. An improvement in the recycling technology
itself is required. This study was carried out on four home appliance products, and it was found that the Home Appliance Recycling
Law has brought significant reductions in GHG emissions. There is also room to make GHG reductions through improving the processing
methods further.
Recommendations and Perspectives The impact on GHG emissions by fluorocarbons of air conditioners and refrigerators is the greatest. Adequate measures are
particularly required for air conditioners that may continue to discharge GHGs in the future.
ESS-Submission Editor: Dr. Lindita Bushi (lindita.bushi@ghgm.com) 相似文献
923.
T Yamamoto N Katsumata K Tachibana H G Friesen J I Nagy 《The journal of histochemistry and cytochemistry》1992,40(2):221-229
We used Western blot and immunohistochemical methods to investigate the biochemical characteristics and cellular distribution of a novel peptide (peptide 23) that was previously shown to be released from anterior pituitary cells of rat in response to growth hormone-releasing hormone. In the pituitary, peptide 23 isolated from intact cells had an Mr of 31,000, whereas that released into culture medium had an Mr of 16,000. Pancreatic islets contained a 19 KD form of the peptide. Immunohistochemically, peptide 23 in the rat pituitary gland was localized in a subpopulation of somatotropes. In pancreatic islets, the peptide was found by triple immunofluorescence labeling to be present in both insulin- and somatostatin-containing cells. In the gastrointestinal tract, peptide 23 was found only in a subpopulation of endocrine cells in the pyloric glands. This subpopulation of cells was found to be entirely separate from those containing either serotonin or somatostatin, and may represent one of the other known or as yet biochemically uncharacterized cell types in this gland. The results suggest that in response to secretagogues in vitro, an altered form of the peptide is secreted from pituitary cells and that an intracellular form of peptide 23 is expressed in some but not all somatotropes, a large proportion of islet cells, and a distinct population of pyloric cells. 相似文献
924.
This study demonstrated that 20 mg/kg of the Ca2+ channel blocker, diltiazem hydrochloride, administered by intraperitoneal injection 15 min before 200 mg/kg of alloxan given by the same route to induce diabetes, served to suppress disease onset completely in rats. Even though 48-h fasting promoted the onset of alloxan diabetes, 40 mg/kg of diltiazem hydrochloride completely prevented the occurrence of diabetes induced by intraperitoneal injection of 200 mg/kg of alloxan. Forty mg/kg of the same agent, however, failed to prevent the onset of diabetes induced by the intravenous injection of streptozotocin (50 mg/kg). From the fact that Ca2+ channel blockers such as nicardipine, verapamil and bepridil have a similar suppressive effect on the occurrence of alloxan diabetes, one may readily infer that this action is characteristic of Ca2+ channel blockers. Moreover, the results suggest the close connection of Ca2+ in the occurrence of alloxan diabetes in rats. 相似文献
925.
926.
The accumulation of cross-immunity in the host population is an important factor driving the antigenic evolution of viruses such as influenza A. Mathematical models have shown that the strength of temporary non-specific cross-immunity and the basic reproductive number are both key determinants for evolutionary branching of the antigenic phenotype. Here we develop deterministic and stochastic versions of one such model. We examine how the time of emergence or introduction of a novel strain affects co-existence with existing strains and hence the initial establishment of a new evolutionary branch. We also clarify the roles of cross-immunity and the basic reproductive number in this process. We show that the basic reproductive number is important because it affects the frequency of infection, which influences the long term immune profile of the host population. The time at which a new strain appears relative to the epidemic peak of an existing strain is important because it determines the environment the emergent mutant experiences in terms of the short term immune profile of the host population. Strains are more likely to coexist, and hence to establish a new clade in the viral phylogeny, when there is a significant time overlap between their epidemics. It follows that the majority of antigenic drift in influenza is expected to occur in the earlier part of each transmission season and this is likely to be a key surveillance period for detecting emerging antigenic novelty. 相似文献
927.
The effect of phosphine on respiration of rat liver mitochondria 总被引:2,自引:0,他引:2
928.
Yoshinao Katsumata Keizo Sato Shoichi Yada Osamu Suzuki Masataka Yoshino 《Life sciences》1983,33(2):151-155
In order to investigate the changes in energy metabolism during acute anoxia, blood levels of various metabolites were analysed in cyanide-poisoned rats. After intraperitoneal injection of a sublethal dose of potassium cyanide (5 mg/kg), blood samples were obtained by cervical dislocation at intervals of 5 min until 30 min. Lacatate and lactate/pyruvate ratio (L/P) in plasma concomitantly changed with cyanide; increased rapidly at 5 min, remained fairly constant until 20 min and then began to decrease at 25 min. In contrast, the products of ATP degradation, oxypurines and inorganic phosphate (Pi), increased gradually until 25 min and then began to decrease at 30 min. Allantoin in plasma scarcely increased throughout the experiments. The results indicate that the rapid activation of anaerobic ATP formation by glycolysis was followed by the increase in ATP degradation in cyanide-poisoned rats. Thus, increase in plasma oxypurines could be regarded as an indicator for severe anoxic states in tissues with massive ATP degradation. 相似文献
929.
930.