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101.
102.
Masaaki Fukushima Misao Shioya Keiji Wakai Hidetoshi Ibe 《Journal of Material Cycles and Waste Management》2009,11(1):11-18
Sapporo Plastics Recycling Co., Ltd., (SPR) started its commercial operation of waste plastics liquefaction in 2000. At first
only hydrocarbon oil was reclaimed, this being derived from the waste plastics liquefaction process under the Japanese Containers
and Packaging Recycling Law. Presently, thermal degradation residue and hydrochloric acid are being produced as by-products
in addition to the hydrocarbon oil. As a result, the SPR plastics liquefaction plant has achieved a high reclamation rate
of 96%, and 93% of the recycled products have been reused in Hokkaido, where SPR is located. The technical problems caused
by corrosion and clogging have been solved.
Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6 相似文献
103.
采用非线性有限单元法和笔者曾提出的动孔压试验曲线法,对某深厚黄土覆盖层上土石坝进行了有效应力法地震响应分析,重点分析大坝的绝对加速度、动位移和动应力等动力响应及动孔隙水压力分布情况。分析结果表明,在现有设计条件下,由于坝基软弱黄土覆盖层较厚,大坝在7度地震作用下地震响应不强烈,但坝基黄土覆盖层会出现液化情况,需采取相应的抗液化工程措施。 相似文献
104.
This research investigated the possibility of using recycled asphalt concrete as surface course in airport pavement. The basic properties of recycled asphalt binder after short- and long-term aging were firstly tested and compared with those of the virgin asphalt. Then, a series of laboratory tests were performed to evaluate the performance of recycled asphalt concrete (containing 40% and 70% RAP), in which the HMA mixture without RAP was used as a control. Furthermore, an experimental pavement consisting of three sections (corresponding to 0%, 40% and 70% RAP content) was constructed to verify the laboratory test results. These results indicated that the recycled asphalt could achieve the similar properties against long-term aging as virgin asphalt. Recycled asphalt concrete containing 40% RAP could be used as surface course in airport pavement as it exhibited similar performance as control mixture both from the laboratory and experimental pavement test results. On the contrary, recycled asphalt concrete containing 70% RAP was not recommended as its fatigue property was much poorer compared with that of virgin asphalt mixture. 相似文献
105.
Edward R. Long 《Environmental monitoring and assessment》2000,64(1):391-407
Acute, laboratory toxicity tests were performed by the National Oceanic and Atmospheric Administration (NOAA) on 1543 surficial sediment samples collected during 1991 through 1997 throughout 25 estuaries and marine bays. Selected areas were sampled along the Atlantic, Gulf of Mexico, and Pacific coasts. The toxicity of each sample was determined with 10-day amphipod survival tests performed with solid-phase (bulk) sediments. Collectively, the 1543 samples tested through 1997 represented a total area of approximately 7300 km2. Toxicity was observed with the amphipod survival tests in samples that represented approximately 6% of the combined area. Using similar tests conducted on samples collected in different, but overlapping, study areas, the U.S. Environmental Protection Agency (EPA) estimated that approximately 7% of the combined estuarine area sampled was toxic. Generally, toxicity was most severe in northeastern and southwestern estuaries and least prevalent in southeastern and northwestern areas. However, considerable portions of the Pacific coast have not been tested with the same methods. In tests of CYP1A enzyme induction (n=464), samples were toxic that represented about 5% of the combined study areas. Toxicity was much more widespread, however, when the results of two sub-lethal tests were analyzed. Significant results occurred in samples that represented approximately 25% and 39% of the study areas in tests of sea urchin fertilization (n=1309) and microbial bioluminescence (n=1215), respectively. 相似文献
106.
Jaroslav Mohapl 《Environmental monitoring and assessment》2000,61(3):407-417
Though measurement instruments and methods have their natural precision limits, long term monitoring, which is so importantfor environmental studies, requires to set up and maintaincertain standards regarding precision. The elementaryrequirement is to produce measurements with a prescribed numberof valid digits. If the technology further develops and allowsto increase the number of valid digits, the change should bedocumented. In this paper we discuss a simple procedure for validity assessment of the last digits of data in a data base.It may be useful for both calibration control of an instrumentas well as for preliminary data analysis in scientific studies.The procedure utilizes the assumption that, under normalconditions, the last digits of the observed data can usually beconsidered as uniformly distributed random numbers. Failures ordeliberate changes in the observation mechanism can be detectedif particular digits occur more frequently than the others. Thedecision about proper representations of the last digits is doneby means of the familiar chi-square statistics. 相似文献
107.
Haruhiro Ino Yoshihisa Matsumoto Ryo Takahashi Kazukiyo Takami Junya Nishino Masaaki Itoh 《Journal of Material Cycles and Waste Management》2008,10(2):129-133
H-ZSM-5 zeolite-supported gallium oxides were studied as aromatization catalysts for polyolefin pyrolysate. The catalysts
were prepared by a conventional physical mixing method with a gallium content of 1.0 and 4.5 wt% and were reduced in flowing
hydrogen at 585°C. To test their activity, a polyolefin sample was pyrolyzed and passed over a heated catalyst layer; the
product was analyzed by gas chromatography/mass spectrometry. A continuous-flow fixed-bed reactor was used for aromatization
of a model gas of polyolefin pyrolysate. For chlorine-free sources at 450°C, the catalyst with only 1.0 wt% gallium exhibited
activity comparable to a gallium silicate catalyst. For chlorine-contaminated sources, the catalyst with 4.5 wt% gallium sustained
catalytic activity for long periods. From the activity test results, it was found that zeolite-supported gallium catalysts
prepared by the physical mixing method are suitable for converting polyolefin into aromatic hydrocarbons. 相似文献
108.
Laboratory longitudinal diffusion tests: 1. Dimensionless formulations and validity of simplified solutions 总被引:1,自引:1,他引:0
To obtain reliable diffusion parameters for diffusion testing, multiple experiments should not only be cross-checked but the internal consistency of each experiment should also be verified. In the through- and in-diffusion tests with solution reservoirs, test interpretation of different phases often makes use of simplified analytical solutions. This study explores the feasibility of steady, quasi-steady, equilibrium and transient-state analyses using simplified analytical solutions with respect to (i) valid conditions for each analytical solution, (ii) potential error, and (iii) experimental time. For increased generality, a series of numerical analyses are performed using unified dimensionless parameters and the results are all related to dimensionless reservoir volume (DRV) which includes only the sorptive parameter as an unknown. This means the above factors can be investigated on the basis of the sorption properties of the testing material and/or tracer. The main findings are that steady, quasi-steady and equilibrium-state analyses are applicable when the tracer is not highly sorptive. However, quasi-steady and equilibrium-state analyses become inefficient or impractical compared to steady state analysis when the tracer is non-sorbing and material porosity is significantly low. Systematic and comprehensive reformulation of analytical models enables the comparison of experimental times between different test methods. The applicability and potential error of each test interpretation can also be studied. These can be applied in designing, performing, and interpreting diffusion experiments by deducing DRV from the available information for the target material and tracer, combined with the results of this study. 相似文献
109.
防灾工程项目评估的基本问题 总被引:9,自引:1,他引:8
在分析防灾工作项目特点的项目上,提出了防灾工程项目评估的基本原则,对并防灾工程项目效益和费用的确认与计量问题进行讨论,为进一步研究防灾工程项目评估理论和方法奠定了基础。 相似文献
110.