Carbendazim induces a temporary change in soil bacterial community structure

The effect of carbendazim applications on the diversity and structure of a soil bacterial community was studied under field conditions using temperature gradient gel electrophoresis (TGGE) and partial sequence analysis of PCR-amplified 16S rRNA gene. After four successive introductions of carbendazim at a level of 0.94 kg active ingredient (a.i.)/ha, the genetic diversity (expressed as Shannon index, H0) decreased from 1.43 in the control to 1.29 in treated soil. This harmful e ect seems to increase with the concentration of carbendazim. The value of H0 in the soil treated with carbendazim at 4.70 kg a.i./ha was reduced to 1.05 (P 6 0.05). The structure of soil bacterial community was also a ected after four repeated applications of carbendazim at levels of 0.94, 1.88 and 4.70 kg a.i./ha, as seen in the relative intensities of the individual band. However, the bacterial community in carbendazim-treated soil recovered to that in the control 360 d after the first treatment. The results indicated that repeated applications of carbendazim could reduce soil microbial diversity and alter the bacterial community structure temporarily.     

富勒烯化学修饰与生物医学应用研究进展(Trends in Studies on Chemical Modification and Biomedical Applications of Fullerenes)

富勒烯以及内嵌金属富勒烯作为一种新型含碳纳米材料,由于其独特的结构和物理化学性质,在生物、医学、超导、光学及催化等多领域有着极为广阔的应用前景.在生物和医学领域,富勒烯及其衍生物具有抗氧化活性和细胞保护作用、抗菌活性、抗病毒作用、载带药物和肿瘤治疗等活性.但是富勒烯本身难以直接溶于生物友好介质中,且制备过程中残存的有机溶剂容易引起生物毒性,富勒烯需要进行合适的化学修饰来进一步改善其生物活性,这些问题已成为其在生物医学领域应用的主要障碍.在总结国内外相关研究基础上,论文重点综述了富勒烯及其衍生物的生物医学应用,同时对其化学修饰与毒性相关性研究进行了阐述.     

Direct spectral analysis and determination of high content of carcinogenic bromine in bread using UV pulsed laser induced breakdown spectroscopy

Laser induced breakdown spectroscopy (LIBS) was applied for the detection of carcinogenic elements like bromine in four representative brands of loaf bread samples and the measured bromine concentrations were 352, 157, 451, and 311 ppm, using Br I (827.2 nm) atomic transition line as the finger print atomic transition. Our LIBS system is equipped with a pulsed laser of wavelength 266 nm with energy 25 mJ pulse^?1, 8 ns pulse duration, 20 Hz repetition rate, and a gated ICCD camera. The LIBS system was calibrated with the standards of known concentrations in the sample (bread) matrix and such plot is linear in 20–500 ppm range. The capability of our system in terms of limit of detection and relative accuracy with respect to the standard inductively coupled plasma mass spectrometry (ICPMS) technique was evaluated and these values were 5.09 ppm and 0.01–0.05, respectively, which ensures the applicability of our system for Br trace level detection, and LIBS results are in excellent agreement with that of ICPMS results.     

Ecosystem Services in Urban Landscapes: Practical Applications and Governance Implications

Urban landscapes are the everyday environment for the majority of the global population, and almost 80 % of the Europeans live in urban areas. The continuous growth in the number and size of urban areas along with an increasing demand on resources and energy poses great challenges for ensuring human welfare in cities while preventing an increasing loss of biodiversity. The understanding of how urban ecosystems function, provide goods and services for urban dwellers; and how they change and what allows and limits their performance can add to the understanding of ecosystem change and governance in general in an ever more human-dominated world. This Special Issue aims at bridging the knowledge gap among urbanization, demand creation, and provisioning of ecosystem services in urban regions on the one hand and schemes of urban governance and planning on the other.     

生态浮床技术应用研究

随着工农业的发展,我国的水污染问题日益严重,其中湖泊、水库的富营养化问题尤为突出,如何有效控制水体富营养化是人们关注的热点问题。生态浮床技术以其独特的优点,越来越受到人们的重视,逐渐被应用于富营养化水体的治理中。分析了该技术的工作原理,介绍了国内外的一些应用实例,最后结合应用中存在的问题,对其发展前景进行了展望。     

复采煤层孔隙结构变化及自燃特性研究

为了研究复采煤层的自燃发火规律,采用程序升温实验与低温液氮吸附实验,对复采与原生煤样的孔隙结构和自燃特性进行实验研究。研究表明,由于复采煤样前期的开采破坏,复采煤样的微孔以及小孔所占百分比增大4.395%,比表面积是原生煤样的1.48倍。复采与原生煤样均出现滞后现象,但在相同压力时,复采煤样剩余吸附量与吸附量之差要大于原生煤样,复采煤样最大吸附量也要多于原生煤样。此外,复采煤样也拥有更多墨水瓶孔,最终导致复采煤样吸附氧的能力要大于原生煤样,氧化反应更加剧烈,更易自燃发火。宏观表现为复采煤样产生的CO浓度以及耗氧速率均高于原生煤样。     

Alum split applications strengthened phosphorus fixation and phosphate sorption in high legacy phosphorus calcareous soil

High phosphorus (P) saturation arising from historic P inputs to protected vegetable fields (PVFs) drives high P mobilisation to waterbodies. Amendment of soils with alum has shown potential in terms of fixing labile P and protecting water quality. The present 15 month pot experiment investigated P stabilisation across single alum application (Alum-1 treatment, 20 g alum/kg soil incorporated into soil before the maize was sown), alum split applications (Alum-4 treatment, 5 g alum/kg soil incorporated into soil before each crop was sown i.e. 4 × 5 g/kg) and soil only treatment (Control). Results showed that the Alum-1 treatment caused the strongest stabilisation of soil labile P after maize plant removal, whereas the P stabilisation effect was gradually weakened due to the transformation of soil non-labile P to labile P and the reduced active Al³⁺ in soil solution. For the Alum-4 treatment, soil labile P decreased gradually with each crop planting and was lower than the Alum-1 treatment at the end of the final crop removal, without any impairment on plant growth. The better P stabilisation at the end of Alum-4 treatment was closely correlated with a progressive supply of Al³⁺ and a gradual decrease of pH, which resulted in higher contents of poorly-crystalline Al, Fe and exchangeable Ca. These aspects were conducive to increasing the soil P stabilisation and phosphate sorption. In terms of management, growers in continuous cropping systems could utilise split alum applications as a strategy to alleviate P losses in high-P enriched calcareous soil.     

微生物絮凝剂的研究现状与发展趋势

相对于传统絮凝剂而言,微生物絮凝剂具有絮凝效果好、应用范围广、易生物降解、对环境安全、无二次污染的特点。文章综述了微生物絮凝剂的类型和特点,详细阐述了其絮凝机理,分析了影响微生物絮凝剂絮凝性能的因素以及微生物絮凝剂在水处理中的应用。指出了当前微生物絮凝剂研究存在的问题以及今后的发展趋势。     

Measurement Of Nutrients In Green House Soil With Laser Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) has been applied for the determination of nutrients in the green house soil samples. We determined appropriate spectral signatures of vital nutrients and calibrated the method to measure the nutrients in a naturally fertilized plot, cultivated with tomato and cucumber plants. From the calibration curves we predicted the concentrations of important nutrients such as Ca, K, P, Mg, Fe, S, Ni and Ba in the soil. Our measurements proved that the LIBS method rapidly and efficiently measures soil nutrients with excellent detection limits of 12, 9, 7, 9, 7, 10, 8 and 12~mg/kg for Ca, K, P, Mg, Fe, S, Ni and Ba respectively with a precision of 2%, The unique features of LIBS for rapid sample analysis demonstrated by this study suggests that this method offers promise for precision measurements of soil nutrients as compared to conventional methods in short span of time.     

Sustainable tyre remanufacturing: an agent-based simulation modelling approach

This paper addresses sustainable benefits of remanufacturing tyres. An agent-based simulation approach is used to tackle this research problem by identifying different agents such as tyre, collector, recycler and remanufacturer. Details related to every agent are provided to show the decisions taken by these agents and the impact that may have on tyres' remanufacturing industry. Relying on input data from published reports and papers by academics and professional organisations, experiments are conducted on various scenarios to show the benefits of increasing the retread percentage of passenger car tyres. The results show that retreaded tyre can capture almost 25% of replacement (sales) market, resulting in significant reduction in scrap tyres and raw material consumption. This percentage can further be increased by increasing the number of retreads per used tyre and the life of tread rubber. The output results help in finding the profit break‐even point at various levels of retread. The results also show other decision-making implications, particularly related to rejection rate and ways to reduce it.