碳酸锶生产废水的处理方法

该发明涉及一种碳酸锶生产废水的处理方法。过程为：废水用质量分数为25％～50％的H2O2溶液与质量分数为0．01％～5．00％的市售聚丙烯酰胺絮凝剂的水溶液澄清、再用质量分数为25％～50％的H2O2溶液脱硫、然后加入锰的彰和铁的氧化物分解。采用该发明的碳酸锶生产废水处理方法，出水中杂质含量少，可循环利用于碳酸锶生产过程的硫化锶浸取工段，对产品碳酸锶质量的改善有利；     

蚀刻液水合肼还原除铜

将电路板厂废弃的蚀刻液,经氢氧化铜沉淀法回收大部分铜后,再采用水合肼还原,进一步除铜。反应温度为50℃,水合肼质量分数为3．0％,溶液pH为6．0,废液中铜的去除率可达98.5％,处理后废液中铜的质量浓度低于0．2g／L,可作为碱性蚀刻液重复利用。     

流动注射-氢化物发生-原子吸收法测定土壤中微量砷

用混酸消解土壤试样，用体积分数为20％的盐酸作酸介质，质量分数为1．5％的硼氢化钾作还原剂，体积分数为1％的盐酸作载液，采用流动注射-氢化物发生三-原子吸收法定量测定土壤中的微劈砷。通过实验确定，在原子化温度为920℃、土壤中共存元素含量低于5mg／kg时对测定无干扰。该方法的榆出限为0．5μg/L，线性范嘲为5～100μg/L．相对标准偏差为0．89％，平均回收率达98．99％：     

膜萃取和CaO-MgO乳状液反萃取法由醋酸废水生产醋酸钙镁盐

采用磺化聚醚砜中空纤维膜萃取醋酸废水,再用CaO—MgO乳状液反萃取制备醋酸钙镁盐。考察了膜萃取和反萃取的最佳实验条件。单级膜萃取醋酸废水（醋酸质量分数2％）的最佳条件为：水相走管程有机相走壳程（水外油内）逆流、有机相流量与水相流量比1．3、水相流量0．23mL/min,在此条件下萃取率可达74％;采用二级萃取,总萃取率可达95％。反萃取的最佳条件为：采用质量浓度100g／L的CaO—MgO乳状液作反萃取剂,CaO—MgO与醋酸摩尔比1．0：2．0,投料钙与镁摩尔比2．9：7．0,反萃取时间30min,室温,在此条件下反萃取率高于97％。     

含铬电镀废水中Cr(Ⅵ)的萃取分离研究

用体积分数为40％的磷酸三丁酯－煤油溶液为萃取剂,采用溶液萃取法处理含铬[Cr(Ⅵ）]电镀废水。预先调节废水中Cr(Ⅵ）的质量浓度约为100mg/L,溶液酸度为1．3－1．5mol/L,相比为1∶2,振荡时间为35min,于室温下进行二级萃取处理,Cr(Ⅵ）的萃取率可达到99％以上。萃余液中Cr(Ⅵ）的残余质量浓度降至0．5mg/L以下,达到国家排放标准。对负载有机相用质量分数为10％的Na2SO3溶液进行反萃,即可得到再生,循环使用。     

利用味精废液生产高蛋白秸秆生物饲料的方法

该发明公开了一种利用味精废液生产高蛋白秸秆生物饲料的方法。其制备步骤如下：将味精废液、发酵剂喷洒到秸秆或秸秆粉上拌匀,加水搅拌后装袋密封、堆放发酵,其中原料的质量比为秸秆70—90份、味精废液10～30份,发酵剂为秸秆或秸秆粉质量的0．2％～1．0％。该发明综合利用味精废液和农作物秸秆两大污染环境的有机废弃物,生产高蛋白秸秆生物饲料,饲料蛋白含量高,     

利用含铜蚀刻废液生产碱式碳酸铜

介绍了利用含铜蚀刻废液生产碱式碳酸铜的生产工艺、技术特点、工艺流程和产品质量。以碳酸钠作蚀刻废液的除杂剂,对其进行除杂前处理,控制反应液的pH为3．5～4．0、反应液中碳酸钠的浓度为0．02～0．03mol／L。可除去其中大部分杂质。用碳酸钠与含铜溶液中的铜进行合成反应,控制反应温度为70～80℃、pH为8～9、碳酸钠和含铜溶液中铜的浓度均为1mol／L,反应生成碱式碳酸铜,此产品中铜的质量分数为56％,产品质量优于木材防腐用碱式碳酸铜国内外同类产品。     

阳离子聚丙烯酰胺絮凝剂的制备及其絮凝性能

研究了丙烯酰胺（AM）与丙烯酰氧乙基三甲皋氯化铵共聚反应制备阳离子聚丙烯酰胺絮凝剂的工艺。实验结果表明,最佳聚合条件：pH6．0、（NH4）2S2O8和CH3NaO3S·2H2O总质量分数0．0125％、（NH4）：S2O8与CH3NaO3S·2H2O质量比1．0、偶氮类化合物质量分数0．0125％、单体质量分数（AM和阳离子单体总质量占整个反应体系的质量分数）35％、阳离子度（阳离子单体占AM和阳离子单体之和的质量分数）30％、反应温度25℃。在最佳条件下,所得阳离子聚丙烯酰胺絮凝剂的特性黏数为13．8535dl／g,在其加入量为0．027％的条件下处理污泥,上层清液透光率达99．6％,污泥脱水率达90．5％。并用红外光谱对阳离子聚丙烯酰胺的结构进行了表征。     

用磷泥生产磷铜母合金的方法

该发明涉及一种用磷泥生产磷铜母合金的方法：向熔磷槽内投入磷泥，加热至高于黄磷熔点的温度下熔融；在蒸磷锅内加入相当于锅容积1／6～1／2的水，然后将熔融后的磷泥引入蒸磷锅内，加热至285～400℃产生磷蒸气；将磷蒸气通入气液吸收反应器与可溶性铜盐水溶液反廊；反应后含固液两相的混合物通过固液分离装置进行分离；固液分离所得崮体产物继续用水冲洗、过滤，直至滤液中无铜离子和元素磷检出；所得固体产物十燥至水的质量分数小于5％，即得磷铜母合金（P质量分数不低于14．5％，Cu质量分数不低于83．2％）。     

电渗析法处理低浓度乙酸废液的研究

用电渗析法处理配制的乙酸质量分类为２．５％左右的乙酸水溶液，浓缩液乙酸质量分数达到２０％，稀相出水乙酸质量分数至０．０２％；对影响处理过程的因素进行了探讨。     

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.     

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.     

Effects of Nitrogen Deposition on Bryophyte Species Composition of Calcareous Grasslands

Regular additions of NH₄NO₃ (35–140 kg N ha⁻¹ yr⁻¹) and (NH₄)₂SO₄ (140 kg N ha⁻¹ yr⁻¹) to a calcareous grassland in northern England over a period of 12 years have resulted in a decline in the frequency of the indigenous bryophyte species and the establishment of non-indigenous calcifuge species, with implications for the structure and composition of this calcareous bryophyte community. The lowest NH₄NO₃ additions of 35 kg N ha⁻¹ yr⁻¹ produced significant declines in frequency of Hypnum cupressiforme, Campylium chrysophyllum, and Calliergon cuspidatum. Significant reductions in frequency at higher NH₄NO₃ application rates were recorded for Pseudoscleropodium purum, Ctenidum molluscum, and Dicranum scoparium. The highest NH₄NO₃ and (NH₄)₂SO₄ additions provided conditions conducive for the establishment of two typical calcifuges – Polytrichum spp. and Campylopus introflexus, respectively. Substrate-surface pH measurements showed a dose-related reduction in pH with increasing NH₄NO₃ deposition rates of 1.6 pH units between the control and highest deposition rate, and a further significant fall in pH, of >1 pH unit, between the NH₄NO₃ and (NH₄)₂SO₄ treatments. These results suggest that indigenous bryophyte composition may be at risk from nitrogen deposition rates of 35 kg N ha⁻¹ yr⁻¹ or less. These effects are of particular concern for rare or endangered species of low frequency.