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301.
The aim of this study was to investigate the pollution characteristics of typical veterinary antibiotics in manure and soil of livestock farms in Jiangsu province. This investigation employed solid-phase extraction (SPE) coupled with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). A total of 53 manure and 50 amended soil samples from 16 livestock farms in Jiangsu province were collected for analysis. In the manure samples, the highest detected frequencies and concentrations were those of tetracyclines (TCs, 54.1 ± 5775.6 μgkg?1), followed by fluoroquinolones (FQs, 8.4 ± 435.6 μgkg?1), sulphonamides (SAs, 3.2 ± 5.2 μgkg?1) and macrolides (MACs, 0.4 ± 110.5 μgkg?1). Statistical analysis was used to illuminate the pollution characteristics of 23 veterinary antibiotics for various animal types and different regions in Jiangsu province. The results showed that the pollution level in cow manure was relatively lower compared with pig and chicken manure due to the relative restriction of medication. Furthermore, contamination was serious in amended soil from chicken farms. The pollution level in manure among different regions was higher to the south and north compared with the centre of the region. The same outcome was found for soil. Antibiotic residues in organic fertilizer were also investigated in this study. We found that although the detected concentration was lower in organic fertilizer than in fresh manure, detection frequencies (10–90%) were high, especially for roxithromycin (90%) in MACs (30–90%). This finding suggests attention should be paid to the pollution levels in organic fertilizer. This study is the first extensive investigation of the occurrence and distribution of many kinds of typical veterinary antibiotics in manure and soil from livestock farms of Jiangsu province. This investigation systematically assesses veterinary antibiotics usage and related emissions in southeast China.  相似文献   
302.
ADAM暖体假人(Advanced Thermal Manikin)是当今世界上最先进的热能测试人体舒适度模型。是热能测试人体模型技术上的一个飞跃。ADAM是由美国国家可再生资源实验室和美国西北测试科技公司(MTNW)共同研制的,用来精确检测车辆和航行器内短时间的环境变化。ADAM有126个独立的发汗区,可以高度精确地模拟人在不同环境气候条件下的感觉和舒适度,以及人体的各种反应,如出汗、呼吸等等。  相似文献   
303.
文章收集了台湾921集集地震的强地震动和震害调查资料,利用统计分析的方法,分析了建筑物破坏的数量、震中距、地表加速度之间的关系,对集集地震做了基于地震动参数的易损性初步分析。  相似文献   
304.
燃煤机组超低排放改造对汞的脱除效果研究   总被引:1,自引:0,他引:1  
燃煤烟气中汞污染的控制是目前重要的环保课题之一,燃煤电厂利用现有的脱硝、脱硫、除尘设备去除汞,文章分析燃煤电厂烟气净化设备超低排放改造后汞的排放水平,说明现有废气处理设施超低排放改造,既能有效降低烟尘、二氧化硫、氮氧化物排放浓度,也有利于汞的去除,燃煤机组超低排放改造后汞的排放浓度远低于现行0.03 mg/m3的限值;通过分析燃煤电厂现有烟气净化设备对汞的协同去除效果和脱除汞的原理,提出了未来燃煤烟气汞污染控制措施的建议.  相似文献   
305.
回收网络与回收模式的选择对再生资源企业非常关键。在实践中,存在分散型、层级管理、柔性管理、点对点及承包协议等多种不同的回收模式,而且各自具备不同的特点。基于对不同回收模式的比较分析,针对每种模式分别提出以下建议:以政策规范分散回收行为、以宣传推广柔性管理模式、以共生提高层级网络效率、以信息平台扩大点对点模式、以市场运行承包协议模式。  相似文献   
306.
In this study, we report a novel magnetic biomimetic nanozyme(Fe_3O_4@Cu/GMP(guanosine5′-monophosphate)) with high laccase-like activity, which could oxidize toxic ophenylenediamine(OPD) and remove phenolic compounds.The magnetic laccase-like nanozyme was readily obtained via complexed Cu~(2+)and GMP that grew on the surface of magnetic Fe_3O_4 nanoparticles.The prepared Fe_3O_4@Cu/GMP catalyst could be magnetically recycled for at least five cycles while still retaining above 70% activity.As a laccase mimic,Fe_3O_4@Cu/GMP had more activity and robust stability than natural laccase for the oxidization of OPD.Fe_3O_4@Cu/GMP retained about 90% residual activity at 90℃ and showed little change at pH 3–9, and the nanozyme kept its excellent activity after long-term storage.Meanwhile, Fe_3O_4@Cu/GMP had better activity for removing phenolic compounds, and the removal of naphthol was more than 95%.Consequently, the proposed Fe_3O_4@Cu/GMP nanozyme shows potential for use as a robust catalyst for applications in environmental remediation.  相似文献   
307.
江苏省环保专项资金一般根据专家经验对项目核定后进行事前补助,事后开展针对项目财务支出的合规性评价,但忽视了专家核定补助金额是否合理。根据近3年江苏省燃煤发电机组SCR脱硝工艺典型项目审计报告,分析了项目审计核定支出额与专家核定支出额的规模(100 MW级及以下、300 MW级、600 MW级及以上)差异、区域(苏南、苏中、苏北)差异及其影响因素,发现100 MW级及以下机组环保资金审计核定支出额显著高于专家核定补助额,在剔除100 MW级及以下机组后,苏南地区项目环保资金审计核定支出额显著高于专家核定补助额,基于此提出了项目补助费用校正优化建议,为环保资金科学分配、提高财政资金支出效率提供了理论依据。  相似文献   
308.
Aerobic granular sludge was cultivated by using different kinds of seed sludge in sequencing batch airlift reactor.The influence of seed sludge on physical and chemical properties of granular sludge was studied;the microbial community structure was probed by using scanning electron microscope and polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DGGE).The results showed that seed sludge played an important role on the formation of aerobic granules.Seed sludge taken from beer wastewater treatment plant(inoculum A) was more suitable for cultivating aerobic granules than that of sludge from municipal wastewater treatment plant(inoculum B).Cultivated with inoculum A, large amount of mature granules formed after 35 days operation, its SVI reached 32.75 mL/g, and SOUR of granular sludge was beyond 1.10 mg/(g·min).By contrast, it needed 56 days obtaining mature granules using inoculum B.DGGE profiles indicated that the dominant microbial species in mature granules were 18 and 11 OTU when inoculum A and B were respectively employed as seed sludge.The sequencing results suggested that dominant species in mature granules cultivated by inoculum A were Paracoccus sp., Devosia hwasunensi, Pseudoxanthomonas sp., while the dominant species were Lactococcus raffinolactis and Pseudomonas sp.in granules developed from inoculum B.  相似文献   
309.
以B(iNO)3·35H2O和T(iSO)42为反应物,用异丙醇助水热法制备了钛酸铋光催化剂,并研究不同水热温度和水热时间对样品光催化活性的影响。用XRD表征了样品的结构,UV-vis漫反射测试显示含有Bi12TiO20的样品的吸收带发生了红移,BET测试表明样品的比表面积远远高于化学溶剂分解法制备的钛酸铋的比表面积。以甲基橙为模拟污染物,评价了样品的光催化性能,发现当水热反应温度为140℃,水热反应时间为2.5h时,样品的光催化活性最高,且超过P25。  相似文献   
310.
A strain,USTB-05,isolated from Lake Dianchi,China,degraded the cyanobacterial toxin microcystin-RR(MC-RR) at the rate of 16.7 mg/L per day.Analysis of 16S rDNA sequence showed that the strain was Sphingopyxis sp.Enzymatic degradation pathways for MC-RR by Sphingopyxis sp.USTB-05 were identified.Adda-Arg peptide bond of MC-RR was cleaved and then a hydrogen and a hydroxyl were combined onto the NH 2 group of Adda and the carboxyl group of arginine to form a linear molecule as intermediate product within the ...  相似文献   
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