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1.
在充分调研的基础上,分析阐述了再生资源回收行业新税收政策实施一年来,对再生资源回收行业产生的巨大影响。为促进行业健康发展,提出了完善再生资源回收行业税收政策的建议。  相似文献   

2.
介绍了河北省再生资源行业发展现状,包括再生资源回收总量、总值及再生资源行业发展的特点。经过多年的发展,河北省再生资源行业规模不断扩大,技术水平和管理水平均有提升,同时,也存在着行业竞争力差、技术装备落后、企业融资难等问题。通过分析研究,对创新再生资源回收业务模式,培育龙头企业,走产业化发展道路等提出建议。  相似文献   

3.
全面回顾了2012—2021年我国再生资源行业在回收规模、回收体系和回收模式方面的发展成果,针对行业发展仍然存在的薄弱环节,系统提出未来推动再生资源回收利用高质量发展的建议。  相似文献   

4.
宁夏地区再生资源的回收利用,对推动当地循环经济的发展和环境保护起着非常重要的作用。通过实地调查研究,分析了宁夏再生资源回收利用行业的现状、特点及问题,并提出了发展当地再生资源回收利用行业的对策和建议。  相似文献   

5.
简要阐述了再生资源回收利用概念的演变、内涵,通过对再生资源回收利用行业发展现状、再生资源回收利用行业标准发展现状以及影响再生资源回收利用标准发展原因等方面的分析,提出再生资源回收利用标准科学分类、标准化技术委员会建设、标准制定、推广与应用、标准化人才队伍建设等的基本思路。  相似文献   

6.
指出城市再生资源回收行业现状严重制约城市环境的健康发展,提出建立科学规范的再生资源回收利用网络体系是实现城市环境健康发展的必然要求,同时对行业发展提出具体建议.  相似文献   

7.
2016年5月25日,商务部流通业发展司发布《中国再生资源回收行业发展报告(2016)》,本刊全文刊出,为广大读者全面了解我国再生资源回收行业发展状况及趋势提供参考。  相似文献   

8.
中国再生资源开发有限公司作为供销总社的控股企业和我国最大的专业性再生资源回收利用企业,努力拼搏,改革创新,抢抓机遇,构建回收网络体系,立足环保,注重科技研发,现已发展成为再生资源行业的龙头企业,推动了再生资源产业的升级发展。  相似文献   

9.
介绍了河北省再生资源回收体系发展的现状,从政策环境和市场前景两个方面分析了河北省再生资源行业面临的发展环境,并从创新互联网+模式、创新联合执法模式、推进农村再生资源回收体系建设等角度,对河北省建设再生资源回收体系的措施进行总结。  相似文献   

10.
加强再生资源回收利用服务江苏经济社会发展   总被引:1,自引:0,他引:1  
以江苏供销合作社系统为例,回顾了近年来再生资源行业的发展变化,分析了构建再生资源回收利用体系的对策,阐述了加强再生资源回收利用的意义。  相似文献   

11.
Concentrations and total quantity of cadmium (Cd), cupper (Cu),lead (Pb) and zink (Zn) were determined in biomass and soil compartments in a replicated tree species experiment with 27-yr-old stands growing on former farmland in N.E. Sweden. Sequentialextractions of soil samples were performed in order to estimate the exchangeable and an organically bound fraction of each element. The tree species included were Picea abies (L.)H. Karst., Pinus sylvestris L., Pinus contorta Dougl., Larix sibirica Ledeb., and Betula pendula Roth.Tree species influenced the rate of removal of Cu, Pb and Zn incase of stemwood harvesting, and of Cd, Cu and Zn in the case ofwhole-tree harvesting. B. pendula and P. abies had higher quantities and average concentrations of Zn in the biomass. For all species, >50% of the Zn in the stems was found in the bark. P. abies and L. sibirica had higher quantities of Cu in the biomass than the other species.P. abies and P. contorta had high quantities of Cd inthe biomass in relation to the other species. Branches and stembark contained high concentrations of Cd and Pb in relation to foliage and stemwood. Dead branches had especially high concentrations of Pb. The high accumulation rate of Zn in thebiomass of B. pendula was related to a low exchangeable amount of Zn in the A horizon. In the superficial centimeters ofthe A horizon, a depletion similar to that found for Zn was detected for Cu, whereas for Cd and Pb, no correlations were found between quantities of elements in the trees and element pools in the soil.  相似文献   

12.
The major forest nonpoint source control programs in the West are largely regulatory, either under forest practices acts (California, Idaho, New Mexico, Nevada, Oregon, and Washington) or a streamside management act (Montana). These programs and the specific rules they enforce continue to undergo intensive scrutiny. Still, the questions are the same for these regulatory programs as for states that base nonpoint source control on voluntary BMPs (Arizona, Colorado, Utah, Wyoming). Are the rules or BMPs being applied, and are they effective in reducing nonpoint source pollution to levels that protect beneficial uses of water? The level of debate about forestry in the West has resulted in detailed monitoring and research to answer these questions. In the past, state agencies have assumed levels of BMP compliance based on the percent of operations without enforcement actions. These estimates are being replaced by statistically valid and reproducible monitoring of forest practices rules and BMP compliance levels. BMP effectiveness is being assessed using both qualitative and quantitative methods. This can involve field assessments, process-based research, and control watershed studies. Some trend monitoring is also beginning. With the regional implementation rate for forestry BMPs at about 94% and rising, it is likely that effectiveness testing will continue to be a priority and consume the majority of assessment resources for this region.  相似文献   

13.
Recent starch-plastic research at the National Center for Agricultural Utilization Research is reviewed and related worldwide efforts are noted. Properties of starch that influence its formulation and performance in plastics are discussed. Methods are given for preparation of starch-poly(methyl acrylate) graft copolymer, starch-poly(ethylene-co-acrylic acid), and starch-poly(ethylene-co-acrylic acid)-polyethylene plastics. Their physical properties are discussed, as is degradability by enzymes or amylolytic organisms from soil, ponds, and streams.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.  相似文献   

14.
Application of Cellulose Microfibrils in Polymer Nanocomposites   总被引:1,自引:0,他引:1  
Cellulose microfibrils obtained by the acid hydrolysis of cellulose fibers were added at low concentrations (2–10% w/w) to polymer gels and films as reinforcing agents. Significant changes in mechanical properties, especially maximum load and tensile strength, were obtained for fibrils derived from several cellulosic sources, including cotton, softwood, and bacterial cellulose. For extruded starch plastics, the addition of cotton-derived microfibrils at 10.3% (w/w) concentration increased Young’s modulus by 5-fold relative to a control sample with no cellulose reinforcement. Preliminary data suggests that shear alignment significantly improves tensile strength. Addition of microfibrils does not always change mechanical properties in a predictable direction. Whereas tensile strength and modulus were shown to increase during addition of microfibrils to an extruded starch thermoplastic and a cast latex film, these parameters decreased when microfibrils were added to a starch–pectin blend, implying that complex interactions are involved in the application of these reinforcing agents.  相似文献   

15.
高浓度、高盐分的四氮唑生产废水通过三效蒸发浓缩,馏出液经铁炭氧微电解和混凝预处理,再采用水解酸化一接触氧化一反应二沉主体组合工艺进行处理。研究了该工艺所需构筑物和设备的设计与选型。该工艺在正常运行条件下,处理后出水pH6~9,COD 302mg/L,BOD5 108mg/L,SS30mg/L,色度36倍,水质达到GB8978--1996(污水综合排放标准》三级标准。  相似文献   

16.
Extremely high emissions of S and N compounds in Central Europe (both 280 mmol m-2 yr-1) declined by 70and 35%, respectively, during the last decade. Decreaseddeposition rates of SO4 -2, NO3 -, and NH4 + in the region paralleled emission declines. The reduction in atmospheric inputs of S and N to mountain ecosystemshas resulted in a pronounced reversal of acidification in the Tatra Mountains and Bohemian Forest lakes. Between the 1987–1990and 1997–1999 periods, concentrations of SO4 -2 and NO3 - decreased (average ± standard deviation) by 22±7 and 12±7 mol L-1, respectively, in theTatra Mountains, and by 19±7 and 15±10 mol L-1, respectively, in the Bohemian Forest. Their decrease was compensated in part (1) by a decrease in Ca2+ + Mg2+ (17±7 mol L-1) and H+ (4±6 mol L-1), and an increase in HCO3 -(10±10 mol L-1) in the Tatra Mountains lakes, and (2) by a decrease in Al (7±4 mol L-1), Ca2+ + Mg2+ (9±6 mol L-1), and H+ (6±5 mol L-1), in Bohemian Forest lakes. Despite the rapid decline in lake water concentrations of SO4 -2 and NO3 - in response to reduced S and N emissions, their present concentrations in some lakes are higher than predictionsbased on observed concentrations at comparable emission rates during development of acidification. This hysteresis in chemical reversal from acidification has delayed biological recovery of the lakes. The only unequivocal sign of biological recovery hasbeen observed in erné Lake (Bohemian Forest) where a cladoceran species Ceriodaphnia quadrangular has recentlyreached its pre-acidification abundance.  相似文献   

17.
Stuchlík  E.  Appleby  P.  Bitušík  P.  Curtis  C.  Fott  J.  Kopáček  J.  Pražáková  M.  Rose  N.  Strunecký  O.  Wright  R. F. 《Water, Air, & Soil Pollution: Focus》2002,2(2):127-138
Starolesnianske pleso is a small and shallow acid lake in the High Tatra Mountains, situated at 2000 m above sea level, on granitic bedrock, with sparse and thin soil cover. When detailed measurements began in the 1980s Starolesnianske pleso had pH below 5 and only one species of cladoceran zooplankton, the ubiquitous Chydorus sphaericusPalaeolimnological investigations show changes in cladoceran zooplankton and chironomid zoobenthic assemblages since about 1920 and a major change in 1970–1980. The dynamic acidification model MAGIC was used to reconstruct changes in water chemistry over the past 150 years. The results from MAGIC agree well with the sediment record; pH levels gradually decreased from 6.5 in the mid-1800s to about 5.6 in 1920 (first response in biota) to below 5.0 by 1970, and concentrations of inorganic aluminium rose dramatically beginning about 1960. In the 1990s the lake water chemistry showed clear signs of reversal in acidification brought about by a major decline in S deposition.  相似文献   

18.
In 1994, a large survey of soil chemistry was undertaken in thecounty of Värmland in central Sweden (Lundström et al., 1998).The southern part of the county was affected by soilacidification whereas there were no such indications in thenorthern part. To investigate the influence of soil chemistryon the trees at the specific sites, the survey was continued byan analysis of needle chemistry (Norway spruce) which wasundertaken at 150 of the 180 sites, and of tree growth at 65 ofthe 180 sites. Growth was expressed as a ratio between expectedgrowth, estimated with a national, empirical growth model, andthe growth observed in the field. In statistical analyses,using rank correlation, PCA and PLS, there were only weakindications of an influence of soil chemistry on needlechemistry and on tree growth. A moderate correlation betweennitrogen and sulphur in needles was found, which wasinterpreted as an effect of deposition and of processes in thetree canopy. No obvious regional pattern of the growth ratiowas found, in contrast to the clear pattern of soilacidification. The statistical analysis could not with anycertainty point out any of the soil chemistry variables asespecially important for the tree growth ratio.  相似文献   

19.
The removal of a mixture of heavy (toxic) metal cations (copper, nickeland zinc) from liquid effluents was investigated in this study at pilotscale, using counter-current contact mode. The innovative processinvolved the abstraction of metal ions onto fungal biosorbents, followedby the application of flotation for the subsequent solid/liquid separationof biomass particles. The ability of microorganisms to remove metal ionsfrom aqueous solutions is a well-known phenomenon. Nevertheless,engineering considerations are very important in decisions, concerningthe commercial future of biosorption and practical solutions are neededfor certain problems, such as the efficient post-separation ofmetal-loaded biomass. The two processes (flotation and biosorption) caneffectively operate in combination, in what it was termed biosorptiveflotation process. The sorbents may be recycled, after appropriate elutionof metals, as well as the treated (clean) water.  相似文献   

20.
Bioassessment is a useful tool to determine the impact of logging practices on the biological integrity of streams and wetlands. Measuring biota directly has an intuitive appeal for impact assessment, and biota can be superior indicators to physical or chemical characteristics because they can reflect cumulative impacts over time. Logging can affect stream and wetland biota by increasing sedimentation rates, altering hydrologic, thermal, and chemical regimes, and changing the base of food webs. Biotic impacts of logging on streams compared to wetlands probably differ, and in this paper we review some of those differences. In streams, invertebrates, fishes, amphibians, algae, and macrophytes have been used as indicators of logging impacts. In wetlands, bioassessment is just beginning to be used, and plants and birds are the most promising indicator taxa. Various best management practices (BMPs) have been developed to reduce the impacts of logging on stream and wetland biota, and we review quantitative studies that have evaluated the efficacy of some of these techniques in streams and wetlands in the eastern United States. Remarkably few studies that address the overall efficacy of BMPs in limiting biotic changes in streams and wetlands after BMP implementation have been published in scientific journals, although some work exists in reports or is unpublished. We review these works, and compile conclusions about BMP efficacy for biota from this body of research.  相似文献   

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