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981.
2 semiarid irrigated area with salt-affected soils. The available soil map is at 1:100,000 scale and its mapping units are
used for the land evaluation with the FAO framework. These data are then elaborated using the index value method. This procedure
gives a map of land evaluation units and a table that rates the productive potential of these units for six crops: alfalfa,
barley, maize, rice, sunflower, and wheat. 相似文献
982.
Andréa MM Peres TB Luchini LC Pettinelli A 《Journal of environmental science and health. Part. B》2000,35(3):297-307
The soil oxidative and anaerobic processes, as well as, the microbial biomass were followed during three years in a cotton farm (Tatuí) where the recommended pesticides have been used for several years, and in an experimental field (S?o Paulo) treated first time with the same pesticides. The oxidative process was monitored by the dehydrogenase (DHA)-activity using triphenyltetrazolium chloride (TTC) as substrate. The anaerobic process was followed by the iron-oxide reduction, and the microbial biomass was estimated by the substrate (glucose)-indiced respiration. Increases in DHA-activity and in the microbial biomass occurred only in the farm soil, with concomitant decreases in iron-reduction. In the experimental field soil, the increases in DHA-activity were followed only by decreases in iron-reduction. Soil characteristics were the determining factor for different biological parameters after pesticide inputs. All the pesticides produced at least one clear but transient effect. 相似文献
983.
984.
Chemical Treatments of Natural Fiber for Use in Natural Fiber-Reinforced Composites: A Review 总被引:2,自引:0,他引:2
Xue Li Lope G. Tabil Satyanarayan Panigrahi 《Journal of Polymers and the Environment》2007,15(1):25-33
Studies on the use of natural fibers as replacement to man-made fiber in fiber-reinforced composites have increased and opened
up further industrial possibilities. Natural fibers have the advantages of low density, low cost, and biodegradability. However,
the main disadvantages of natural fibers in composites are the poor compatibility between fiber and matrix and the relative
high moisture sorption. Therefore, chemical treatments are considered in modifying the fiber surface properties.
In this paper, the different chemical modifications on natural fibers for use in natural fiber-reinforced composites are reviewed.
Chemical treatments including alkali, silane, acetylation, benzoylation, acrylation, maleated coupling agents, isocyanates,
permanganate and others are discussed. The chemical treatment of fiber aimed at improving the adhesion between the fiber surface
and the polymer matrix may not only modify the fiber surface but also increase fiber strength. Water absorption of composites
is reduced and their mechanical properties are improved. 相似文献
985.
Status of recycling end-of-life vehicles and efforts to reduce automobile shredder residues in Korea
Hyun-Tae Joung Sung-Jin Cho Yong-Chil Seo Woo-Hyun Kim 《Journal of Material Cycles and Waste Management》2007,9(2):159-166
The present end-of-life vehicle (ELV) recycle rate and management status during the dismantling stage were investigated to
aid the establishment of policies for the management of ELVs by surveying information and using the results gained from questionnaires
given to dismantlers. The average recycle rate at the dismantling stage was 44% of the mass of a new vehicle and the rest
of the ELV was then compressed and transported to shredding companies to recover mainly the iron content, which averaged 38.7%
of the mass of a new vehicle. Nonferrous metals such as copper, antimony, zinc, and aluminum accounted for only 1.5%. The
automobile shredder residues (ASRs) were composed of light and heavy fluffs and soil/dust and amounted to 15.8% based on the
mass of a new vehicle. The dumping of fluff and inorganic residues in landfill sites, however, will be restricted when new
regulations are implemented to reduce the disposal amount to less than 5% of a new car, as has been done in European countries
and in Japan. The detailed characteristics of ASR were investigated to suggest appropriate means of treatment such as volume
reduction or the utilization of thermal technologies to meet future expected enforcement. Also, some concerns on hazardous
pollutant release such as that of dioxins while utilizing such thermal treatment methods were considered. The present on-going
research and development projects to meet such future management targets are also introduced. 相似文献
986.
Yuichi Moriguchi 《Journal of Material Cycles and Waste Management》2007,9(2):112-120
This article reviews recent progress in material flow analysis and its use in providing resource productivity indicators and
is based on developments in Japanese policy toward a sound material-cycle society and in international forums such as within
the Organisation for Economic Development and Cooperation, covering both institutional and methodological issues. Indicators
derived from economy-wide material flow accounts such as direct material inputs are useful to demonstrate the absolute size
of a physical economy and to reinforce the need to both reduce consumption of natural resources and limit waste generation.
Interpretation of material flows as resources and potential environmental impacts is discussed, and linkages between the size
of material flows and specific environmental impacts and damage must be further elaborated for use in environmental policy.
Lessons learned from the practical use of resource productivity indicators are also discussed. Additional indicators are needed
that can be used to evaluate the performance of microeconomic contributors. The need for an integrated approach that links
upstream resource issues and downstream waste issues through the 3Rs concept or the circular economy/society concept is attracting
increasing attention. Consequently, the accumulation of reliable scientific knowledge and data in this field in a fully international
context is essential. 相似文献
987.
Biodegradation of Polycaprolactone Powders Proposed as Reference Test Materials for International Standard of Biodegradation Evaluation Method 总被引:1,自引:0,他引:1
Masahiro Funabashi Fumi Ninomiya Masao Kunioka 《Journal of Polymers and the Environment》2007,15(1):7-17
Polycaprolactone (PCL) powders were prepared from PCL pellets using a rotation mechanical mixer. PCL powders were separated
by sieves with 60 and 120 meshes into four classes; 0–125 μm, 125–250 μm, 0–250 μm and 250–500 μm. Biodegradation tests of
PCL powders and cellulose powders in an aqueous solution at 25°C were performed using the coulometer according to ISO 14851.
Biodegradation tests of PCL powders and cellulose powders in controlled compost at 58°C were performed by the Mitsui Chemical
Analysis and Consulting Service, Inc. according to ISO 14855-1 and by using the Microbial Oxidative Degradation Analyzer (MODA)
instrument according to ISO/DIS 14855-2. PCL powders were faster biodegraded than cellulose powders. The reproducibility of
biodegradation of PCL powders is excellent. Differences in the biodegradation of PCL powders with different class were not
observed by the ISO 14851 and ISO/DIS 14855-2. An enzymatic degradation test of PCL powders with different class was studied
using an enzyme of Amano Lipase PS. PCL with smaller particle size was faster degraded by the enzyme. PCL powders with regulated sizes from 125 μm to 250 μm
are proposed as a reference material for the biodegradation test. 相似文献
988.
J. L. Bardasano J. Álvarez-Ude I. Gutiérrez M. Raposo R. Goya 《The Environmentalist》2007,27(4):519-523
Objectives This paper aims to provide evidence of an inductive electromagnetic bioeffect on the human brain, which is independent from
sound waves and produced by mobile phones, in proximal field, through correlating the EEG data obtained from electrodes placed
on both normal and cochlear deaf individuals.
Methods Two groups of subjects are placed under controlled electromagnetic conditions inside a Faraday chamber, 12 healthy and another
12 suffering from cochlear deafness). Each is sitting on a chair, fitted with additional support, and holding a cellular phone
2 cm away form the right auricular, in order to avoid a thermal effect as much as possible. All of them, relaxed and with
their eyes closed, are EEG recorded in a basal state with their mobile phones off. Then, each of them is again recorded under
the same conditions but with the mobile on and listening to the same conversation. In order to assess the observed EEG changes,
a statistical analysis by means of the FFT (Fast Fourier Transform) was carried out.
Results For both, healthy and cochlear deaf, assimilation or integration of the mobile phone signal by some electrodes is to be found.
This is due to the increase of amplitudes for alpha and theta waves, whereas the signal is not integrated in other electrodes.
By correlating the spectra of frequencies of corresponding EEG records for the same brain areas, we have not observed significative
differences for both groups.
Conclusions A possible electromagnetic direct inductive, non-thermal, bioeffect on the human brain is observed. This effect is produced
by the use of mobile phones and it bears no relation to the sound waves. 相似文献
989.
990.