C9-AA水溶性石油树脂的制备及其阻垢性能

以乙烯生产过程中的副产物C9馏分和丙烯酸为原料,采用自由基溶液聚合,合成具有阻垢性能的C9-AA水溶性石油树脂。考察了引发剂AIBN和溶剂的加入量、C9-AA加入量、Ca^2＋浓度、循环冷却水pH和养护时间对C9-AA水溶性石油树脂阻垢性能的影响,并对其阻垢效果进行了评价。在Ca^2＋质量浓度小于或等于600mg／L、循环冷却水pH小于或等于9．3、C9-AA水溶性石油树脂加入量大于或等于15mg／L的条件下,C9—AA水溶性石油树脂对循环冷却水的阻垢率达到90％以上,其有效作用时间为60h。     

新型膦磺酸阻垢缓蚀剂SEDMP的性能评定

对自制的新型膦磺酸阻垢缓蚀剂SEDMP对CaCO3和Ca3(PO4)2的阻垢性能进行评定。在SEDMP加入量为4 mg/L、浓缩至水溶液中Ca2+质量浓度为500 mg/L时,SEDMP对CaCO3的阻垢率为90.6%,对CaCO3的阻垢效果大大优于其他有机膦类阻垢剂。当SEDMP加入量为10 mg/L时,对Ca3(PO4)2的阻垢率为96.0%。SEDMP作为缓蚀剂单独使用时具有一定的缓蚀效果,与磺酸盐共聚物、锌盐复配后效果更佳。SEDMP与常用杀菌剂同时使用时仍可保持良好的对CaCO3的阻垢性能,且不影响杀菌剂的杀菌率。     

自催化法合成聚天冬氨酸

以马来酸酐和乙酸铵为原料,在微波条件下用自催化法合成了聚天冬氨酸（PASP）。通过正交实验确定了最佳合成条件：n（乙酸铵）：n（马来酸酐）=1．2,微波功率为1200W,反应时间为10min。在最佳合成条件下,PASP的收率为91．6％,PASP的黏均相对分子质量约为1．5×10^4。经红外光谱表征和核磁共振氢谱测试结果表明,PASP的各种主要官能团表现明显。当Ca^2＋质量浓度为250mg／L、PASP加入量为3mg／L时,PASP的阻垢率达到95％,表明PASP具有较好的阻垢性能。     

反渗透阻垢剂HLH-201的性能研究

采用静态阻垢法和动态阻垢法对自行研制的以聚环氧琥珀酸为主的反渗透阻垢剂HLH-201进行了性能研究.静态阻垢结果表明,阻垢剂质量浓度为4.0 mg/L时,对CaCO3的阻垢率达到89.0％.动态阻垢结果表明,HLH-201能够满足对黄河水的阻垢要求,在加酸调节pH为6.8～7.0时,浓缩倍数可以达到5.0倍.     

Ca(OH)2、高岭土与FeCl3组配处理含Pb2+废水

采用Ca（OH）2、高岭土与FeCl3组配处理含Pb^2＋废水。考察了Ca（OH）2加入量、高岭土加入量、FeCl3加入量、废水pH、搅拌转速、沉淀时间等因素对Pb^2＋去除率的影响。在Ca（OH）2加入量50mg／L、高岭土加入量90mg／L、FeCl3加入量13．2mg／L、废水pH7．0～8．0、搅拌转速170r／min、沉淀时间90min的条件下,该法可将废水中金属离子（包括Pb^2＋及少量的Zn^2＋,Cu^2＋,Cr^3＋,Ni^2＋）的质量浓度由42．4mg／L降至1．0mg／L以下,达到了GB18918--2002〈《城镇污水处理厂污染物排放标准》。     

高铁酸钾预氧化-三氯化铁混凝去除水中AS^3＋

采用K2FeO4预氧化-Fecl3混凝联合去除水中的As^3＋,考察了适宜的K2FeO4预氧化时间、Fe^3＋和Fe^6＋加入量,分析了预氧化pH、混凝pH、碳酸盐和腐殖酸浓度对该工艺去除As^3＋效果的影响。实验结果表明：K2FeO4预氧化的适宜时间为2min;加入质量浓度为2．4mg／L的Fe^6＋和14．0mg／L的Fe^3＋能使处理后水样中的As^3＋浓度符合GB-57492006《生活饮用水卫生标准》（As^3＋质量浓度小于0．01mg／L）;预氧化pH在4～9范围内,对K2FeO4预氧化-FeCl3混凝去除As^3＋的效果影响不大;FeCl3混凝阶段适宜的pH为6．0～8．5。碳酸盐对K2FeO4预氧化-Fecl,混凝去除As^3＋的效果基本没有影响;腐殖酸的存在使As^3＋的去除率有一定程度的降低。     

N,N-二膦酰基甲基牛磺酸的制备与阻垢缓蚀性能

以牛磺酸、甲醛和三氯化磷为原料制备了N,N-二膦酰基甲基牛磺酸（BPMT）。探讨了原料配比、反应温度、反应时间对BPMT质量的影响,考察了BPMT的阻垢缓蚀性能,并与N,N-二膦酰基甲基氨基磺酸、N,N-二膦酰基甲基氨基甲磺酸、丙烯酸／2-丙烯酰胺-2-甲基丙磺酸、2-膦酸基-1,2,4-三羧基丁烷等进行了比较。实验结果表明,当n（牛磺酸）：n（三氯化磷）：n（甲醛）=1：2：4、反应温度110℃、反应时间2h时,BPMT的质量较好。BPMT的阻碳酸钙垢和稳定锌的性能优于其他阻垢剂,阻磷酸钙垢和分散氧化铁的性能仅次于丙烯酸／2-丙烯酰胺-2-甲基丙磺酸。当BPMT加入量为40mg／L时,缓蚀效果最好。     

黑藻对铅离子的生物吸附

研究了黑藻对Pb^2＋的生物吸附作用,考察了溶液pH、Pb^2＋初始质量浓度、黑藻加入量和吸附时间对吸附效果的影响。实验结果表明,溶液pH在2．5～5．0时吸附效果最好,吸附20min基本达到平衡。在溶液pH为4．0、黑藻加入量为2g／L、吸附时间为60min、Pb^2＋初始质量浓度为100mg／L的条件下,黑藻对Pb^2＋的吸附量为47．5mg／g。通过元素分析和等温吸附模型对黑藻吸附Pb^2＋的机理进行了研究,发现黑藻吸附Pb“是阳离子交换过程,吸附符合Langmuir、Freundlich和D—R等温吸附模型。考察了Cd^2＋、Cu^2＋和Ni^2＋对黑藻吸附Pb^2＋的影响,结果表明,Cd^2＋、Cu^2＋和Ni^2＋的存在不干扰黑藻对Pb^2＋的吸附。     

Z系列多功能药剂用于处理油田废水

采用Z系列多功能药剂处理油田废水,使絮凝、阻垢、防腐和 杀菌过程一步完成。处理后水中总铁质量浓度≤0.5mg/L,Ca^2 、Mg^2 的质量浓度由1875mg/L降低到350mg/L,其他指标匀达到部颁标准。处理 后水的水质更接近地层水,具有良好的稳定性和配伍性。     

Cu^2＋改性活性炭的制备及其去除废水中CN^-的研究

以活性炭为载体负载溶液中的Cu^2＋,Cu^2＋改性活性炭对溶液中CN^-的去除效果较好。cu。’改性活性炭的最佳制备条件：活性炭加入量为1g,质量浓度为5∥L的CuSO。溶液加入量为50mL,溶液pH为4,负载时间为5．0h.在此最佳条件下活性炭的最大Cu^2＋负载量为25．90mg（以每克活性炭计）。Cu^2＋改性后活性炭的CN^-去除率明显提高,由22．10％提高至94．07％。Cu^2＋改性活性炭吸附CN^-的最佳实验条件：溶液pH为12～13,吸附时间为9h。Cu^2＋改性活性炭对CN^-的饱和吸附量为22mg／g。Mg^2＋,K^＋,Ca^2＋,Cl^-,SO4^2-,CO3^2-,AsO3^-对Cu^2＋改性活性炭的CN^-去除率基本没有影响。Cu^2＋改性活性炭的动态吸附实验表明,开始一段时间流出液中CN^-含量几乎为零,远低于国家排放标准（0．5mg／L）。     

Distribution of Cd,Ck, Pb and Zn in Soil and Vegetation Compartments in Stands of Five Boreal Tree Species in N.E. Sweden

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.     

Starch-plastic materials—Preparation,physical properties,and biodegradability (a review of recent USDA research)

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.     

Application of Cellulose Microfibrils in Polymer Nanocomposites

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.     

四氮唑废水处理工艺设计

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。     

Bioassessment of silvicultural impacts in streams and wetlands of the Eastern United States

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.     

Characterization of air emissions and residual ash from open burning of electronic wastes during simulated rudimentary recycling operations

Air emissions and residual ash samples were collected and analyzed during experiments of open, uncontrolled combustion of electronic waste (e-waste), simulating practices associated with rudimentary e-waste recycling operations. Circuit boards and insulated wires were handled separately to simulate processes associated with metal recovery. The average emissions of polychlorinated dibenzodioxins and dibenzofurans (PCDD/PCDFs) were 92 ng toxic equivalency (TEQ)/kg [n = 2, relative standard deviation (RSD) = 98%] and 11 900 ng TEQ/kg (n = 3, RSD = 50%) of the initial mass of the circuit boards and insulated wire, respectively. The value for the insulated wire is about 100 times higher than that for backyard barrel burning of domestic waste. The emission concentrations of polybrominated dibenzodioxins and dibenzofurans (PBDD/PBDFs) from the combustion of circuit boards were 100 times higher than for their polychlorinated counterparts. Particulate matter (PM) sampling of the fly ash emissions indicated PM emission factors of approximately 15 and 17 g/kg of the initial mass for the circuit boards and insulated wire, respectively. Fly ash samples from both types of e-waste contained considerable amounts of several metallic elements and halogens; lead concentrations were more than 200 times the United States regulatory limits for municipal waste combustors and 20 times those for secondary lead smelters. Leaching tests of the residual bottom ash showed that lead concentrations exceeded U.S. Environmental Protection Agency landfill limits, designating this ash as a hazardous waste.     

Does Soil Acidification Affect Spruce Needle Chemical Composition and Tree Growth?

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.     

Solubility and Potential Mobility of Heavy Metals in Two Contaminated Urban Soils from Stockholm,Sweden

The solubility and potential mobility of heavy metals (Cd, Cu,Hg, Pb and Zn) in two urban soils were studied by sequential andleaching extractions (rainwater). Compared to rural (arable) soils on similar parent material, the urban soils were highlycontaminated with Hg and Pb and to a lesser extent also with Cd,Cu and Zn. Metal concentrations in rainwater leachates were related to sequential extractions and metal levels reported fromStockholm groundwater. Cadmium and Zn in the soils were mainly recovered in easily extractable fractions, whereas Cu and Pb were complex bound. Concentrations of Pb in the residual fractionwere between two- and eightfold those in arable soils, indicatingthat the sequential extraction scheme did not reflect the solidphases affected by anthropogenic inputs. Cadmium and Zn conc. inthe rainwater leachates were within the range detected in Stockholm groundwater, while Cu and Pb conc. were higher, whichsuggests that Cu and Pb released from the surface soil were immobilised in deeper soil layers. In a soil highly contaminatedwith Hg, the Hg conc. in the leachate was above the median concentration, but still 50 times lower than the max concentration found in groundwater, indicating the possibilityof other sources. In conclusion, it proved difficult to quantitatively predict the mobility of metals in soils by sequential extractions.     

High Immobilization of NH4+ in Danish Heath Soil Related to Succession,Soil and Nutrients: Implications for Critical Loads of N

During recent decades heathlands havechanged into grasslands in regions with high atmosphericnitrogen deposition. In regions with intermediatedeposition level (e.g., Denmark) changes have been lesspronounced which may be due to delay or decrease inresponse of the ecosystem. The mor layer (O horizon) mayplay an important role for this delay due to high sinkstrength for N. In this study, the capacity for netNH₄ ⁺ immobilization and mineralization wasstudied during short- and long-term incubations (2–36 days)of mor samples from Danish dry inland heaths. High short-term capacity for net NH₄ ⁺ immobilization wasfound to be a general characteristic of Danish heath morlayers both under heather (Calluna vulgaris) andcrowberry (Empetrum nigrum ssp nigrum), the latterdominating late stages in heathland succession. The netNH₄ ⁺ immobilization was higher under youngcompared to old or dead vegetation, and higher on lessnutrient poor soils than on extremely nutrient poor soils.The addition of N, P and C stimulated CO₂ productionand net NH₄ ⁺ immobilization, but not net Nmineralization. The immobilization of ¹⁵NH₄ ⁺caused release of dissolved organic N, increased N anddecreased C/N ratio in the microbial biomass, and indicatedgrowth of microorganisms with other metabolic abilitiesthan the indigenous population. No evidence was obtained ofstabilization of immobilized ¹⁵NH₄ ⁺ intosoil organic matter during the experiment. On background ofthe results and current knowledge it was concluded that therecognition of the high capacity for net NH₄ ⁺immobilization in mor layers does not allow for a raiseof critical loads for N for northern dry inland heaths.     

Biodegradation of Injection Molded Starch-Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) Blends in a Natural Compost Environment

Injection molded specimens were prepared by blending poly (hydroxybutyrate-co-valerate) (PHBV) with cornstarch. Blended formulations incorporated 30% or 50% starch in the presence or absence of poly-(ethylene oxide) (PEO), which enhances the adherence of starch granules to PHBV. These formulations were evaluated for their biodegradability in natural compost by measuring changes in physical and chemical properties over a period of 125 days. The degradation of plastic material, as evidenced by weight loss and deterioration in tensile properties, correlated with the amount of starch present in the blends (neat PHBV < 30% starch < 50% starch). Incorporation of PEO into starch-PHBV blends had little or no effect on the rate of weight loss. Starch in blends degraded faster than PHBV and it accelerated PHBV degradation. Also, PHBV did not retard starch degradation. After 125 days of exposure to compost, neat PHBV lost 7% of its weight (0.056% weight loss/day), while the PHBV component of a 50% starch blend lost 41% of its weight (0.328% weight loss/day). PHB and PHV moieties within the copolymer degraded at similar rates, regardless of the presence of starch, as determined by ¹H-NMR spectroscopy. GPC analyses revealed that, while the number average molecular weight (Mn) of PHBV in all exposed samples decreased, there was no significant difference in this decrease between neat PHBV as opposed to PHBV blended with starch. SEM showed homogeneously distributed starch granules embedded in a PHBV matrix, typical of a filler material. Starch granules were rapidly depleted during exposure to compost, increasing the surface area of the PHBV matrix.