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51.
发制品行业是以人发、人造纤维等为原材料进行假发加工的行业。许昌市发制品的生产过程大致可分为两个阶段:漂染和前后处理。漂染过程用水量大,产生的废水难以处理。其中过酸、氧化、染色配置的溶液使用一次后直接排放,不符合清洁生产要求,且所排放的溶液可考虑中和多次利用。漂染过程水资源消耗量大,废水产生量大,没有考虑废水综合利用。按清洁生产的要求在以上环节可通过技术革新和设备改造得以改进。  相似文献   
52.
Shi Q  Liu GH  Yan HQ  Zhang HL 《Ambio》2012,41(5):446-455
The northern reef of Yongxing Island, the largest reef island of the Xisha Islands in the South China Sea, was in good condition with significant cover of scleractinian corals until 2002. Surveys in 2008 and 2010, however, found that coral coverage had declined rapidly and severely, implying that catastrophic coral mortality occurred during the past 8 years. A blackish mat was observed covering live and dead corals in both 2008 and 2010 that was identified as an encrusting sponge, Terpios hoshinota, by special surface morphology and spicule structure. In addition, spicule residues were found on the surface of long-dead corals, indicating a previous invasion of T. hosinota. T. hoshinota is referred to as the "black disease" because it rapidly overgrows and kills corals. Our evidence indicates that outbreaks of black disease are at least partially responsible for the massive coral mortality at the northern reef of Yongxing Island over the past 8 years, although human activities and heat-related coral bleaching cannot be discounted as minor causes for this coral decline.  相似文献   
53.
絮凝和生化一体化反应器处理纸浆漂白废水   总被引:12,自引:0,他引:12  
絮凝、厌氧酸化、生物接触氧化一体化反应器处理造纸制浆含氯漂白废水研究表明,在水力停留时间为15h 时,COD总去除率达83.9% ,毒性去除率92% . GC-MS、超滤实验结果表明:原废水污染物是以氯代酚为主的氯代有机物,其中毒性物质主要来源于相对分子质量小于1000的低分子物质. 絮凝单元去除的主要是大分子氯代有机物,厌氧单元通过还原脱氯及酸性水解,氯代有机物得到了基本的去除. 好氧单元对COD有较高的去除率,低分子量的酸性组分和烷烃类明显增加,表明污染物得到了进一步的氧化降解.  相似文献   
54.
The sustained decline in marine fisheries worldwide underscores the need to understand and monitor fisheries trends and fisher behavior. Recreational fisheries are unique in that they are not subject to the typical drivers that influence commercial and artisanal fisheries (e.g., markets or food security). Nevertheless, although exposed to a different set of drivers (i.e., interest or relaxation), recreational fisheries can contribute to fishery declines. Recreational fisheries are also difficult to assess due to an absence of past monitoring and traditional fisheries data. Therefore, we utilized a nontraditional data source (a chronology of spearfishing publications) to document historical trends in recreational spearfishing in Australia between 1952 and 2009. We extracted data on reported fish captures, advertising, and spearfisher commentary and used regression models and ordination analyses to assess historical change. The proportion of coastal fish captures reported declined approximately 80%, whereas the proportion of coral reef and pelagic fish reports increased 1750% and 560%, respectively. Catch composition shifted markedly from coastal temperate or subtropical fishes during the 1950s to 1970s to coral reef and pelagic species in the 1990s to 2000s. Advertising data and commentary by spearfishers indicated that pelagic fish species became desired targets. The mean weight of trophy coral reef fishes also declined significantly over the study period (from approximately 30–8 kg). Recreational fishing presents a highly dynamic social–ecological interface and a challenge for management. Our results emphasize the need for regulatory agencies to work closely with recreational fishing bodies to observe fisher behavior, detect shifts in target species or fishing intensity, and adapt regulatory measures. Tendencias Dinámicas de Captura en la Historia de la Pesca Recreativa con Arpón en Australia  相似文献   
55.
One goal of the Swedish survey project is to discover possible sources of PCDD/F. Bottom sediment and pike were sampled at various sites near different types of industries along the coast line of two lakes and one river. The results show background levels of PCDD/F in some lakes which can only be explained by atmospheric input. In some lakes paper mill emissions of chlorinated PCDD/F give high levels of local contamination (≈1 ng/g IG) within short distances (<1 km) from the source. PCDD/F from paper mill effluents are transported long distances and traces can be detected over the entire lake area. The PCDD/F levels in pike are correlated with levels in the underlying sediment.  相似文献   
56.
中段废水是制浆造纸工业的主要污染源之一,从工程设计的角度出发,对草制浆造纸中段废水处理及回用提出一套可行适用的工艺方案;对主要工艺环节参数、设备备有说明,以供同行借鉴.  相似文献   
57.
The most abundant volatile organochlorine compounds (VOCCs), trichloroacetic and dichloroacetic acids and AOX, were determined in bleaching effluent and waste water from three kraft pulp mills during ClO2 bleaching. 0.6–7.7 g of VOCCs per ton bleached pulp were formed, the most abundant being chloroform and dichloroacetic acid methyl ester. Most of the VOCCs were removed during treatment, and it was estimated that 2–30 t of VOCCs would be removed annually from activated sludge treatment plants in Finnish kraft pulp mills using elemental chlorine free bleaching, most likely by volatilization. Dichloroacetic acid was formed in considerably higher amounts than trichloroacetic acid, and both compounds were removed effectively during treatment. The formation of all organochlorine compounds decreased considerably when non-chlorinated bleaching was employed.  相似文献   
58.
光释光信号已被成功地应用于岩石表层暴露、埋藏年龄的测定以及判别岩石经历的曝光和埋藏历史。本文选择红褐色石英砂岩和灰白色黑云母花岗岩进行了岩块和岩片晒退不同时间的实验研究,结果显示:岩石光释光信号(IR_(50);IRSL)可被光(阳光和全光谱模拟太阳灯灯光)快速晒退。曝光一定时间后,岩块表层一定深度的光释光信号可以归零,且随曝光时间的延长,自暴露面向内的光释光信号归零深度也随之加深。砂岩和花岗岩光晒退对比实验结果显示:与深色砂岩相比,浅色的花岗岩有更高的光释光信号晒退速率。实验同时揭示:本研究所采用的红外光源激发获得的光释光信号来自岩片(1.2 mm)表层一定深度,并没有完全穿透该岩片。该研究为了解不同岩性岩石的光释光信号晒退速率、测年对象的合理选择以及岩石样品采集、前处理和测试等提供了实验数据支持。  相似文献   
59.
Abstract:  Illegal fishing with explosives has damaged coral reefs throughout Southeast Asia. In addition to killing fish and other organisms, the blasts shatter coral skeletons, leaving fields of broken rubble that shift in the current, abrading or burying new coral recruits, and thereby slowing or preventing reef recovery. Successful restoration and rehabilitation efforts can contribute to coral reef conservation. We used field experiments to assess the effectiveness of different low-cost methods for coral reef rehabilitation in Komodo National Park (KNP), Indonesia. Our experiments were conducted at three different spatial scales. At a scale of 1 × 1 m plots, we tested three different rehabilitation methods: rock piles, cement slabs, and netting pinned to the rubble. Significantly more corals per square meter grew on rocks, followed by cement, netting, and untreated rubble, although many plots were scattered by strong water current or buried by rubble after 2.5 years. To test the benefits of the most successful treatment, rocks, at more realistic scales, we established 10 × 10 m plots of rock piles at each of our nine sites in 2000. Three years after installation, coverage by hard corals on the rocks continued to increase, although rehabilitation in high current areas remained the most difficult. In 2002 rehabilitation efforts in KNP were increased over 6000 m2 to test four rock pile designs at each of four rubble field sites. Assuming that there is an adequate larval supply, using rocks for simple, low-budget, large-scale rehabilitation appears to be a viable option for restoring the structural foundation of damaged reefs.  相似文献   
60.
用含氯漂白废水驯化城市污水处理厂的好氧污泥 ,从中分离出两株高效去除有机氯的菌 ,并对其适应条件进行了研究。结果表明 ,当pH为 7.0、废水浓度为 5 0 %、加入 0 .4g/L葡萄糖、2mL菌液时 ,处理效果较好 ,有机氯的去除率最高可达 74 .8%。  相似文献   
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